Update containers/storage and containers/image

Update the versions of containers/storage and containers/image, and add
new dependencies that they pull in.

Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>

hack/.vendor-helpers.sh

@@ -60,7 +60,7 @@ clean() {
 	local packages=($(GOPATH=$original_GOPATH go list -e ./... | grep -v "^${PROJECT}/vendor"))
 	local platforms=( linux/amd64 linux/386 )
 
-	local buildTags=(  )
+	local buildTags=( seccomp )
 
 	echo
 

hack/vendor.sh

@@ -49,7 +49,17 @@ esac
 clone git github.com/coreos/go-systemd master
 clone git github.com/BurntSushi/toml v0.2.0
 clone git github.com/Sirupsen/logrus v0.10.0
-clone git github.com/containers/image f6f11ab5cf8b1e70ef4aa3f8b6fdb4b671d16abd
+
+clone git github.com/containers/storage master
+clone git github.com/mistifyio/go-zfs master
+clone git github.com/pborman/uuid master
+
+clone git github.com/containers/image master
+clone git github.com/mtrmac/gpgme master
+clone git gopkg.in/cheggaaa/pb.v1 master
+clone git github.com/mattn/go-runewidth master
+clone git github.com/docker/engine-api v0.4.0
+
 clone git github.com/opencontainers/image-spec master
 clone git golang.org/x/net 991d3e32f76f19ee6d9caadb3a22eae8d23315f7 https://github.com/golang/net.git
 clone git github.com/docker/docker master
@@ -64,7 +74,7 @@ clone git github.com/opencontainers/runtime-spec bb6925ea99f0e366a3f7d1c975f6577
 clone git github.com/docker/distribution d22e09a6686c32be8c17b684b639da4b90efe320
 clone git github.com/vbatts/tar-split v0.10.1
 clone git github.com/docker/go-units f2145db703495b2e525c59662db69a7344b00bb8
-clone git github.com/docker/go-connections 988efe982fdecb46f01d53465878ff1f2ff411ce
+clone git github.com/docker/go-connections 4ccf312bf1d35e5dbda654e57a9be4c3f3cd0366
 clone git github.com/docker/libtrust 9cbd2a1374f46905c68a4eb3694a130610adc62a
 clone git github.com/ghodss/yaml 73d445a93680fa1a78ae23a5839bad48f32ba1ee
 clone git gopkg.in/yaml.v2 d466437aa4adc35830964cffc5b5f262c63ddcb4

server/image_pull.go

@@ -35,11 +35,15 @@ func (s *Server) PullImage(ctx context.Context, req *pb.PullImageRequest) (*pb.P
 	if err != nil {
 		return nil, err
 	}
-	i := image.FromSource(src)
-	blobs, err := i.BlobDigests()
+	i, err := image.FromSource(src)
 	if err != nil {
 		return nil, err
 	}
+	blobs := i.LayerInfos()
+	config := i.ConfigInfo()
+	if config.Digest != "" {
+		blobs = append(blobs, config)
+	}
 
 	if err = os.Mkdir(filepath.Join(s.config.ImageDir, tr.StringWithinTransport()), 0755); err != nil {
 		return nil, err
@@ -61,7 +65,7 @@ func (s *Server) PullImage(ctx context.Context, req *pb.PullImageRequest) (*pb.P
 		if err != nil {
 			return nil, err
 		}
-		if _, _, err = dest.PutBlob(r, b, -1); err != nil {
+		if _, err = dest.PutBlob(r, b); err != nil {
 			r.Close()
 			return nil, err
 		}

vendor/src/github.com/containers/image/copy/compression.go

@@ -0,0 +1,61 @@
+package copy
+
+import (
+	"bytes"
+	"compress/bzip2"
+	"compress/gzip"
+	"errors"
+	"io"
+
+	"github.com/Sirupsen/logrus"
+)
+
+// decompressorFunc, given a compressed stream, returns the decompressed stream.
+type decompressorFunc func(io.Reader) (io.Reader, error)
+
+func gzipDecompressor(r io.Reader) (io.Reader, error) {
+	return gzip.NewReader(r)
+}
+func bzip2Decompressor(r io.Reader) (io.Reader, error) {
+	return bzip2.NewReader(r), nil
+}
+func xzDecompressor(r io.Reader) (io.Reader, error) {
+	return nil, errors.New("Decompressing xz streams is not supported")
+}
+
+// compressionAlgos is an internal implementation detail of detectCompression
+var compressionAlgos = map[string]struct {
+	prefix       []byte
+	decompressor decompressorFunc
+}{
+	"gzip":  {[]byte{0x1F, 0x8B, 0x08}, gzipDecompressor},                 // gzip (RFC 1952)
+	"bzip2": {[]byte{0x42, 0x5A, 0x68}, bzip2Decompressor},                // bzip2 (decompress.c:BZ2_decompress)
+	"xz":    {[]byte{0xFD, 0x37, 0x7A, 0x58, 0x5A, 0x00}, xzDecompressor}, // xz (/usr/share/doc/xz/xz-file-format.txt)
+}
+
+// detectCompression returns a decompressorFunc if the input is recognized as a compressed format, nil otherwise.
+// Because it consumes the start of input, other consumers must use the returned io.Reader instead to also read from the beginning.
+func detectCompression(input io.Reader) (decompressorFunc, io.Reader, error) {
+	buffer := [8]byte{}
+
+	n, err := io.ReadAtLeast(input, buffer[:], len(buffer))
+	if err != nil && err != io.EOF && err != io.ErrUnexpectedEOF {
+		// This is a “real” error. We could just ignore it this time, process the data we have, and hope that the source will report the same error again.
+		// Instead, fail immediately with the original error cause instead of a possibly secondary/misleading error returned later.
+		return nil, nil, err
+	}
+
+	var decompressor decompressorFunc
+	for name, algo := range compressionAlgos {
+		if bytes.HasPrefix(buffer[:n], algo.prefix) {
+			logrus.Debugf("Detected compression format %s", name)
+			decompressor = algo.decompressor
+			break
+		}
+	}
+	if decompressor == nil {
+		logrus.Debugf("No compression detected")
+	}
+
+	return decompressor, io.MultiReader(bytes.NewReader(buffer[:n]), input), nil
+}

vendor/src/github.com/containers/image/copy/copy.go

@@ -0,0 +1,568 @@
+package copy
+
+import (
+	"bytes"
+	"compress/gzip"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"reflect"
+
+	pb "gopkg.in/cheggaaa/pb.v1"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/image"
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/signature"
+	"github.com/containers/image/transports"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+)
+
+// preferredManifestMIMETypes lists manifest MIME types in order of our preference, if we can't use the original manifest and need to convert.
+// Prefer v2s2 to v2s1 because v2s2 does not need to be changed when uploading to a different location.
+// Include v2s1 signed but not v2s1 unsigned, because docker/distribution requires a signature even if the unsigned MIME type is used.
+var preferredManifestMIMETypes = []string{manifest.DockerV2Schema2MediaType, manifest.DockerV2Schema1SignedMediaType}
+
+type digestingReader struct {
+	source           io.Reader
+	digester         digest.Digester
+	expectedDigest   digest.Digest
+	validationFailed bool
+}
+
+// imageCopier allows us to keep track of diffID values for blobs, and other
+// data, that we're copying between images, and cache other information that
+// might allow us to take some shortcuts
+type imageCopier struct {
+	copiedBlobs       map[digest.Digest]digest.Digest
+	cachedDiffIDs     map[digest.Digest]digest.Digest
+	manifestUpdates   *types.ManifestUpdateOptions
+	dest              types.ImageDestination
+	src               types.Image
+	rawSource         types.ImageSource
+	diffIDsAreNeeded  bool
+	canModifyManifest bool
+	reportWriter      io.Writer
+}
+
+// newDigestingReader returns an io.Reader implementation with contents of source, which will eventually return a non-EOF error
+// and set validationFailed to true if the source stream does not match expectedDigest.
+func newDigestingReader(source io.Reader, expectedDigest digest.Digest) (*digestingReader, error) {
+	if err := expectedDigest.Validate(); err != nil {
+		return nil, fmt.Errorf("Invalid digest specification %s", expectedDigest)
+	}
+	digestAlgorithm := expectedDigest.Algorithm()
+	if !digestAlgorithm.Available() {
+		return nil, fmt.Errorf("Invalid digest specification %s: unsupported digest algorithm %s", expectedDigest, digestAlgorithm)
+	}
+	return &digestingReader{
+		source:           source,
+		digester:         digestAlgorithm.New(),
+		expectedDigest:   expectedDigest,
+		validationFailed: false,
+	}, nil
+}
+
+func (d *digestingReader) Read(p []byte) (int, error) {
+	n, err := d.source.Read(p)
+	if n > 0 {
+		if n2, err := d.digester.Hash().Write(p[:n]); n2 != n || err != nil {
+			// Coverage: This should not happen, the hash.Hash interface requires
+			// d.digest.Write to never return an error, and the io.Writer interface
+			// requires n2 == len(input) if no error is returned.
+			return 0, fmt.Errorf("Error updating digest during verification: %d vs. %d, %v", n2, n, err)
+		}
+	}
+	if err == io.EOF {
+		actualDigest := d.digester.Digest()
+		if actualDigest != d.expectedDigest {
+			d.validationFailed = true
+			return 0, fmt.Errorf("Digest did not match, expected %s, got %s", d.expectedDigest, actualDigest)
+		}
+	}
+	return n, err
+}
+
+// Options allows supplying non-default configuration modifying the behavior of CopyImage.
+type Options struct {
+	RemoveSignatures bool   // Remove any pre-existing signatures. SignBy will still add a new signature.
+	SignBy           string // If non-empty, asks for a signature to be added during the copy, and specifies a key ID, as accepted by signature.NewGPGSigningMechanism().SignDockerManifest(),
+	ReportWriter     io.Writer
+	SourceCtx        *types.SystemContext
+	DestinationCtx   *types.SystemContext
+}
+
+// Image copies image from srcRef to destRef, using policyContext to validate source image admissibility.
+func Image(policyContext *signature.PolicyContext, destRef, srcRef types.ImageReference, options *Options) error {
+	reportWriter := ioutil.Discard
+	if options != nil && options.ReportWriter != nil {
+		reportWriter = options.ReportWriter
+	}
+	writeReport := func(f string, a ...interface{}) {
+		fmt.Fprintf(reportWriter, f, a...)
+	}
+
+	dest, err := destRef.NewImageDestination(options.DestinationCtx)
+	if err != nil {
+		return fmt.Errorf("Error initializing destination %s: %v", transports.ImageName(destRef), err)
+	}
+	defer dest.Close()
+	destSupportedManifestMIMETypes := dest.SupportedManifestMIMETypes()
+
+	rawSource, err := srcRef.NewImageSource(options.SourceCtx, destSupportedManifestMIMETypes)
+	if err != nil {
+		return fmt.Errorf("Error initializing source %s: %v", transports.ImageName(srcRef), err)
+	}
+	unparsedImage := image.UnparsedFromSource(rawSource)
+	defer func() {
+		if unparsedImage != nil {
+			unparsedImage.Close()
+		}
+	}()
+
+	// Please keep this policy check BEFORE reading any other information about the image.
+	if allowed, err := policyContext.IsRunningImageAllowed(unparsedImage); !allowed || err != nil { // Be paranoid and fail if either return value indicates so.
+		return fmt.Errorf("Source image rejected: %v", err)
+	}
+	src, err := image.FromUnparsedImage(unparsedImage)
+	if err != nil {
+		return fmt.Errorf("Error initializing image from source %s: %v", transports.ImageName(srcRef), err)
+	}
+	unparsedImage = nil
+	defer src.Close()
+
+	if src.IsMultiImage() {
+		return fmt.Errorf("can not copy %s: manifest contains multiple images", transports.ImageName(srcRef))
+	}
+
+	var sigs [][]byte
+	if options != nil && options.RemoveSignatures {
+		sigs = [][]byte{}
+	} else {
+		writeReport("Getting image source signatures\n")
+		s, err := src.Signatures()
+		if err != nil {
+			return fmt.Errorf("Error reading signatures: %v", err)
+		}
+		sigs = s
+	}
+	if len(sigs) != 0 {
+		writeReport("Checking if image destination supports signatures\n")
+		if err := dest.SupportsSignatures(); err != nil {
+			return fmt.Errorf("Can not copy signatures: %v", err)
+		}
+	}
+
+	canModifyManifest := len(sigs) == 0
+	manifestUpdates := types.ManifestUpdateOptions{}
+
+	if err := determineManifestConversion(&manifestUpdates, src, destSupportedManifestMIMETypes, canModifyManifest); err != nil {
+		return err
+	}
+
+	// If src.UpdatedImageNeedsLayerDiffIDs(manifestUpdates) will be true, it needs to be true by the time we get here.
+	ic := imageCopier{
+		copiedBlobs:       make(map[digest.Digest]digest.Digest),
+		cachedDiffIDs:     make(map[digest.Digest]digest.Digest),
+		manifestUpdates:   &manifestUpdates,
+		dest:              dest,
+		src:               src,
+		rawSource:         rawSource,
+		diffIDsAreNeeded:  src.UpdatedImageNeedsLayerDiffIDs(manifestUpdates),
+		canModifyManifest: canModifyManifest,
+		reportWriter:      reportWriter,
+	}
+
+	if err := ic.copyLayers(); err != nil {
+		return err
+	}
+
+	pendingImage := src
+	if !reflect.DeepEqual(manifestUpdates, types.ManifestUpdateOptions{InformationOnly: manifestUpdates.InformationOnly}) {
+		if !canModifyManifest {
+			return fmt.Errorf("Internal error: copy needs an updated manifest but that was known to be forbidden")
+		}
+		manifestUpdates.InformationOnly.Destination = dest
+		pendingImage, err = src.UpdatedImage(manifestUpdates)
+		if err != nil {
+			return fmt.Errorf("Error creating an updated image manifest: %v", err)
+		}
+	}
+	manifest, _, err := pendingImage.Manifest()
+	if err != nil {
+		return fmt.Errorf("Error reading manifest: %v", err)
+	}
+
+	if err := ic.copyConfig(pendingImage); err != nil {
+		return err
+	}
+
+	if options != nil && options.SignBy != "" {
+		mech, err := signature.NewGPGSigningMechanism()
+		if err != nil {
+			return fmt.Errorf("Error initializing GPG: %v", err)
+		}
+		dockerReference := dest.Reference().DockerReference()
+		if dockerReference == nil {
+			return fmt.Errorf("Cannot determine canonical Docker reference for destination %s", transports.ImageName(dest.Reference()))
+		}
+
+		writeReport("Signing manifest\n")
+		newSig, err := signature.SignDockerManifest(manifest, dockerReference.String(), mech, options.SignBy)
+		if err != nil {
+			return fmt.Errorf("Error creating signature: %v", err)
+		}
+		sigs = append(sigs, newSig)
+	}
+
+	writeReport("Writing manifest to image destination\n")
+	if err := dest.PutManifest(manifest); err != nil {
+		return fmt.Errorf("Error writing manifest: %v", err)
+	}
+
+	writeReport("Storing signatures\n")
+	if err := dest.PutSignatures(sigs); err != nil {
+		return fmt.Errorf("Error writing signatures: %v", err)
+	}
+
+	if err := dest.Commit(); err != nil {
+		return fmt.Errorf("Error committing the finished image: %v", err)
+	}
+
+	return nil
+}
+
+// copyLayers copies layers from src/rawSource to dest, using and updating ic.manifestUpdates if necessary and ic.canModifyManifest.
+func (ic *imageCopier) copyLayers() error {
+	srcInfos := ic.src.LayerInfos()
+	destInfos := []types.BlobInfo{}
+	diffIDs := []digest.Digest{}
+	for _, srcLayer := range srcInfos {
+		var (
+			destInfo types.BlobInfo
+			diffID   digest.Digest
+			err      error
+		)
+		if ic.dest.AcceptsForeignLayerURLs() && len(srcLayer.URLs) != 0 {
+			// DiffIDs are, currently, needed only when converting from schema1.
+			// In which case src.LayerInfos will not have URLs because schema1
+			// does not support them.
+			if ic.diffIDsAreNeeded {
+				return errors.New("getting DiffID for foreign layers is unimplemented")
+			}
+			destInfo = srcLayer
+			fmt.Fprintf(ic.reportWriter, "Skipping foreign layer %q copy to %s\n", destInfo.Digest, ic.dest.Reference().Transport().Name())
+		} else {
+			destInfo, diffID, err = ic.copyLayer(srcLayer)
+			if err != nil {
+				return err
+			}
+		}
+		destInfos = append(destInfos, destInfo)
+		diffIDs = append(diffIDs, diffID)
+	}
+	ic.manifestUpdates.InformationOnly.LayerInfos = destInfos
+	if ic.diffIDsAreNeeded {
+		ic.manifestUpdates.InformationOnly.LayerDiffIDs = diffIDs
+	}
+	if layerDigestsDiffer(srcInfos, destInfos) {
+		ic.manifestUpdates.LayerInfos = destInfos
+	}
+	return nil
+}
+
+// layerDigestsDiffer return true iff the digests in a and b differ (ignoring sizes and possible other fields)
+func layerDigestsDiffer(a, b []types.BlobInfo) bool {
+	if len(a) != len(b) {
+		return true
+	}
+	for i := range a {
+		if a[i].Digest != b[i].Digest {
+			return true
+		}
+	}
+	return false
+}
+
+// copyConfig copies config.json, if any, from src to dest.
+func (ic *imageCopier) copyConfig(src types.Image) error {
+	srcInfo := src.ConfigInfo()
+	if srcInfo.Digest != "" {
+		fmt.Fprintf(ic.reportWriter, "Copying config %s\n", srcInfo.Digest)
+		configBlob, err := src.ConfigBlob()
+		if err != nil {
+			return fmt.Errorf("Error reading config blob %s: %v", srcInfo.Digest, err)
+		}
+		destInfo, err := ic.copyBlobFromStream(bytes.NewReader(configBlob), srcInfo, nil, false)
+		if err != nil {
+			return err
+		}
+		if destInfo.Digest != srcInfo.Digest {
+			return fmt.Errorf("Internal error: copying uncompressed config blob %s changed digest to %s", srcInfo.Digest, destInfo.Digest)
+		}
+	}
+	return nil
+}
+
+// diffIDResult contains both a digest value and an error from diffIDComputationGoroutine.
+// We could also send the error through the pipeReader, but this more cleanly separates the copying of the layer and the DiffID computation.
+type diffIDResult struct {
+	digest digest.Digest
+	err    error
+}
+
+// copyLayer copies a layer with srcInfo (with known Digest and possibly known Size) in src to dest, perhaps compressing it if canCompress,
+// and returns a complete blobInfo of the copied layer, and a value for LayerDiffIDs if diffIDIsNeeded
+func (ic *imageCopier) copyLayer(srcInfo types.BlobInfo) (types.BlobInfo, digest.Digest, error) {
+	// Check if we already have a blob with this digest
+	haveBlob, extantBlobSize, err := ic.dest.HasBlob(srcInfo)
+	if err != nil && err != types.ErrBlobNotFound {
+		return types.BlobInfo{}, "", fmt.Errorf("Error checking for blob %s at destination: %v", srcInfo.Digest, err)
+	}
+	// If we already have a cached diffID for this blob, we don't need to compute it
+	diffIDIsNeeded := ic.diffIDsAreNeeded && (ic.cachedDiffIDs[srcInfo.Digest] == "")
+	// If we already have the blob, and we don't need to recompute the diffID, then we might be able to avoid reading it again
+	if haveBlob && !diffIDIsNeeded {
+		// Check the blob sizes match, if we were given a size this time
+		if srcInfo.Size != -1 && srcInfo.Size != extantBlobSize {
+			return types.BlobInfo{}, "", fmt.Errorf("Error: blob %s is already present, but with size %d instead of %d", srcInfo.Digest, extantBlobSize, srcInfo.Size)
+		}
+		srcInfo.Size = extantBlobSize
+		// Tell the image destination that this blob's delta is being applied again.  For some image destinations, this can be faster than using GetBlob/PutBlob
+		blobinfo, err := ic.dest.ReapplyBlob(srcInfo)
+		if err != nil {
+			return types.BlobInfo{}, "", fmt.Errorf("Error reapplying blob %s at destination: %v", srcInfo.Digest, err)
+		}
+		fmt.Fprintf(ic.reportWriter, "Skipping fetch of repeat blob %s\n", srcInfo.Digest)
+		return blobinfo, ic.cachedDiffIDs[srcInfo.Digest], err
+	}
+
+	// Fallback: copy the layer, computing the diffID if we need to do so
+	fmt.Fprintf(ic.reportWriter, "Copying blob %s\n", srcInfo.Digest)
+	srcStream, srcBlobSize, err := ic.rawSource.GetBlob(srcInfo)
+	if err != nil {
+		return types.BlobInfo{}, "", fmt.Errorf("Error reading blob %s: %v", srcInfo.Digest, err)
+	}
+	defer srcStream.Close()
+
+	blobInfo, diffIDChan, err := ic.copyLayerFromStream(srcStream, types.BlobInfo{Digest: srcInfo.Digest, Size: srcBlobSize},
+		diffIDIsNeeded)
+	if err != nil {
+		return types.BlobInfo{}, "", err
+	}
+	var diffIDResult diffIDResult // = {digest:""}
+	if diffIDIsNeeded {
+		diffIDResult = <-diffIDChan
+		if diffIDResult.err != nil {
+			return types.BlobInfo{}, "", fmt.Errorf("Error computing layer DiffID: %v", diffIDResult.err)
+		}
+		logrus.Debugf("Computed DiffID %s for layer %s", diffIDResult.digest, srcInfo.Digest)
+		ic.cachedDiffIDs[srcInfo.Digest] = diffIDResult.digest
+	}
+	return blobInfo, diffIDResult.digest, nil
+}
+
+// copyLayerFromStream is an implementation detail of copyLayer; mostly providing a separate “defer” scope.
+// it copies a blob with srcInfo (with known Digest and possibly known Size) from srcStream to dest,
+// perhaps compressing the stream if canCompress,
+// and returns a complete blobInfo of the copied blob and perhaps a <-chan diffIDResult if diffIDIsNeeded, to be read by the caller.
+func (ic *imageCopier) copyLayerFromStream(srcStream io.Reader, srcInfo types.BlobInfo,
+	diffIDIsNeeded bool) (types.BlobInfo, <-chan diffIDResult, error) {
+	var getDiffIDRecorder func(decompressorFunc) io.Writer // = nil
+	var diffIDChan chan diffIDResult
+
+	err := errors.New("Internal error: unexpected panic in copyLayer") // For pipeWriter.CloseWithError below
+	if diffIDIsNeeded {
+		diffIDChan = make(chan diffIDResult, 1) // Buffered, so that sending a value after this or our caller has failed and exited does not block.
+		pipeReader, pipeWriter := io.Pipe()
+		defer func() { // Note that this is not the same as {defer pipeWriter.CloseWithError(err)}; we need err to be evaluated lazily.
+			pipeWriter.CloseWithError(err) // CloseWithError(nil) is equivalent to Close()
+		}()
+
+		getDiffIDRecorder = func(decompressor decompressorFunc) io.Writer {
+			// If this fails, e.g. because we have exited and due to pipeWriter.CloseWithError() above further
+			// reading from the pipe has failed, we don’t really care.
+			// We only read from diffIDChan if the rest of the flow has succeeded, and when we do read from it,
+			// the return value includes an error indication, which we do check.
+			//
+			// If this gets never called, pipeReader will not be used anywhere, but pipeWriter will only be
+			// closed above, so we are happy enough with both pipeReader and pipeWriter to just get collected by GC.
+			go diffIDComputationGoroutine(diffIDChan, pipeReader, decompressor) // Closes pipeReader
+			return pipeWriter
+		}
+	}
+	blobInfo, err := ic.copyBlobFromStream(srcStream, srcInfo, getDiffIDRecorder, ic.canModifyManifest) // Sets err to nil on success
+	return blobInfo, diffIDChan, err
+	// We need the defer … pipeWriter.CloseWithError() to happen HERE so that the caller can block on reading from diffIDChan
+}
+
+// diffIDComputationGoroutine reads all input from layerStream, uncompresses using decompressor if necessary, and sends its digest, and status, if any, to dest.
+func diffIDComputationGoroutine(dest chan<- diffIDResult, layerStream io.ReadCloser, decompressor decompressorFunc) {
+	result := diffIDResult{
+		digest: "",
+		err:    errors.New("Internal error: unexpected panic in diffIDComputationGoroutine"),
+	}
+	defer func() { dest <- result }()
+	defer layerStream.Close() // We do not care to bother the other end of the pipe with other failures; we send them to dest instead.
+
+	result.digest, result.err = computeDiffID(layerStream, decompressor)
+}
+
+// computeDiffID reads all input from layerStream, uncompresses it using decompressor if necessary, and returns its digest.
+func computeDiffID(stream io.Reader, decompressor decompressorFunc) (digest.Digest, error) {
+	if decompressor != nil {
+		s, err := decompressor(stream)
+		if err != nil {
+			return "", err
+		}
+		stream = s
+	}
+
+	return digest.Canonical.FromReader(stream)
+}
+
+// copyBlobFromStream copies a blob with srcInfo (with known Digest and possibly known Size) from srcStream to dest,
+// perhaps sending a copy to an io.Writer if getOriginalLayerCopyWriter != nil,
+// perhaps compressing it if canCompress,
+// and returns a complete blobInfo of the copied blob.
+func (ic *imageCopier) copyBlobFromStream(srcStream io.Reader, srcInfo types.BlobInfo,
+	getOriginalLayerCopyWriter func(decompressor decompressorFunc) io.Writer,
+	canCompress bool) (types.BlobInfo, error) {
+	// The copying happens through a pipeline of connected io.Readers.
+	// === Input: srcStream
+
+	// === Process input through digestingReader to validate against the expected digest.
+	// Be paranoid; in case PutBlob somehow managed to ignore an error from digestingReader,
+	// use a separate validation failure indicator.
+	// Note that we don't use a stronger "validationSucceeded" indicator, because
+	// dest.PutBlob may detect that the layer already exists, in which case we don't
+	// read stream to the end, and validation does not happen.
+	digestingReader, err := newDigestingReader(srcStream, srcInfo.Digest)
+	if err != nil {
+		return types.BlobInfo{}, fmt.Errorf("Error preparing to verify blob %s: %v", srcInfo.Digest, err)
+	}
+	var destStream io.Reader = digestingReader
+
+	// === Detect compression of the input stream.
+	// This requires us to “peek ahead” into the stream to read the initial part, which requires us to chain through another io.Reader returned by detectCompression.
+	decompressor, destStream, err := detectCompression(destStream) // We could skip this in some cases, but let's keep the code path uniform
+	if err != nil {
+		return types.BlobInfo{}, fmt.Errorf("Error reading blob %s: %v", srcInfo.Digest, err)
+	}
+	isCompressed := decompressor != nil
+
+	// === Report progress using a pb.Reader.
+	bar := pb.New(int(srcInfo.Size)).SetUnits(pb.U_BYTES)
+	bar.Output = ic.reportWriter
+	bar.SetMaxWidth(80)
+	bar.ShowTimeLeft = false
+	bar.ShowPercent = false
+	bar.Start()
+	destStream = bar.NewProxyReader(destStream)
+	defer fmt.Fprint(ic.reportWriter, "\n")
+
+	// === Send a copy of the original, uncompressed, stream, to a separate path if necessary.
+	var originalLayerReader io.Reader // DO NOT USE this other than to drain the input if no other consumer in the pipeline has done so.
+	if getOriginalLayerCopyWriter != nil {
+		destStream = io.TeeReader(destStream, getOriginalLayerCopyWriter(decompressor))
+		originalLayerReader = destStream
+	}
+
+	// === Compress the layer if it is uncompressed and compression is desired
+	var inputInfo types.BlobInfo
+	if !canCompress || isCompressed || !ic.dest.ShouldCompressLayers() {
+		logrus.Debugf("Using original blob without modification")
+		inputInfo = srcInfo
+	} else {
+		logrus.Debugf("Compressing blob on the fly")
+		pipeReader, pipeWriter := io.Pipe()
+		defer pipeReader.Close()
+
+		// If this fails while writing data, it will do pipeWriter.CloseWithError(); if it fails otherwise,
+		// e.g. because we have exited and due to pipeReader.Close() above further writing to the pipe has failed,
+		// we don’t care.
+		go compressGoroutine(pipeWriter, destStream) // Closes pipeWriter
+		destStream = pipeReader
+		inputInfo.Digest = ""
+		inputInfo.Size = -1
+	}
+
+	// === Finally, send the layer stream to dest.
+	uploadedInfo, err := ic.dest.PutBlob(destStream, inputInfo)
+	if err != nil {
+		return types.BlobInfo{}, fmt.Errorf("Error writing blob: %v", err)
+	}
+
+	// This is fairly horrible: the writer from getOriginalLayerCopyWriter wants to consumer
+	// all of the input (to compute DiffIDs), even if dest.PutBlob does not need it.
+	// So, read everything from originalLayerReader, which will cause the rest to be
+	// sent there if we are not already at EOF.
+	if getOriginalLayerCopyWriter != nil {
+		logrus.Debugf("Consuming rest of the original blob to satisfy getOriginalLayerCopyWriter")
+		_, err := io.Copy(ioutil.Discard, originalLayerReader)
+		if err != nil {
+			return types.BlobInfo{}, fmt.Errorf("Error reading input blob %s: %v", srcInfo.Digest, err)
+		}
+	}
+
+	if digestingReader.validationFailed { // Coverage: This should never happen.
+		return types.BlobInfo{}, fmt.Errorf("Internal error writing blob %s, digest verification failed but was ignored", srcInfo.Digest)
+	}
+	if inputInfo.Digest != "" && uploadedInfo.Digest != inputInfo.Digest {
+		return types.BlobInfo{}, fmt.Errorf("Internal error writing blob %s, blob with digest %s saved with digest %s", srcInfo.Digest, inputInfo.Digest, uploadedInfo.Digest)
+	}
+	return uploadedInfo, nil
+}
+
+// compressGoroutine reads all input from src and writes its compressed equivalent to dest.
+func compressGoroutine(dest *io.PipeWriter, src io.Reader) {
+	err := errors.New("Internal error: unexpected panic in compressGoroutine")
+	defer func() { // Note that this is not the same as {defer dest.CloseWithError(err)}; we need err to be evaluated lazily.
+		dest.CloseWithError(err) // CloseWithError(nil) is equivalent to Close()
+	}()
+
+	zipper := gzip.NewWriter(dest)
+	defer zipper.Close()
+
+	_, err = io.Copy(zipper, src) // Sets err to nil, i.e. causes dest.Close()
+}
+
+// determineManifestConversion updates manifestUpdates to convert manifest to a supported MIME type, if necessary and canModifyManifest.
+// Note that the conversion will only happen later, through src.UpdatedImage
+func determineManifestConversion(manifestUpdates *types.ManifestUpdateOptions, src types.Image, destSupportedManifestMIMETypes []string, canModifyManifest bool) error {
+	if len(destSupportedManifestMIMETypes) == 0 {
+		return nil // Anything goes
+	}
+	supportedByDest := map[string]struct{}{}
+	for _, t := range destSupportedManifestMIMETypes {
+		supportedByDest[t] = struct{}{}
+	}
+
+	_, srcType, err := src.Manifest()
+	if err != nil { // This should have been cached?!
+		return fmt.Errorf("Error reading manifest: %v", err)
+	}
+	if _, ok := supportedByDest[srcType]; ok {
+		logrus.Debugf("Manifest MIME type %s is declared supported by the destination", srcType)
+		return nil
+	}
+
+	// OK, we should convert the manifest.
+	if !canModifyManifest {
+		logrus.Debugf("Manifest MIME type %s is not supported by the destination, but we can't modify the manifest, hoping for the best...")
+		return nil // Take our chances - FIXME? Or should we fail without trying?
+	}
+
+	var chosenType = destSupportedManifestMIMETypes[0] // This one is known to be supported.
+	for _, t := range preferredManifestMIMETypes {
+		if _, ok := supportedByDest[t]; ok {
+			chosenType = t
+			break
+		}
+	}
+	logrus.Debugf("Will convert manifest from MIME type %s to %s", srcType, chosenType)
+	manifestUpdates.ManifestMIMEType = chosenType
+	return nil
+}

vendor/src/github.com/containers/image/directory/directory_dest.go

@@ -1,14 +1,13 @@
 package directory
 
 import (
-	"crypto/sha256"
-	"encoding/hex"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"os"
 
 	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
 )
 
 type dirImageDestination struct {
@@ -40,16 +39,27 @@ func (d *dirImageDestination) SupportsSignatures() error {
 	return nil
 }
 
-// PutBlob writes contents of stream and returns its computed digest and size.
-// A digest can be optionally provided if known, the specific image destination can decide to play with it or not.
-// The length of stream is expected to be expectedSize; if expectedSize == -1, it is not known.
+// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination.
+func (d *dirImageDestination) ShouldCompressLayers() bool {
+	return false
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (d *dirImageDestination) AcceptsForeignLayerURLs() bool {
+	return false
+}
+
+// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+// inputInfo.Size is the expected length of stream, if known.
 // WARNING: The contents of stream are being verified on the fly.  Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
 // to any other readers for download using the supplied digest.
 // If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlob MUST 1) fail, and 2) delete any data stored so far.
-func (d *dirImageDestination) PutBlob(stream io.Reader, digest string, expectedSize int64) (string, int64, error) {
+func (d *dirImageDestination) PutBlob(stream io.Reader, inputInfo types.BlobInfo) (types.BlobInfo, error) {
 	blobFile, err := ioutil.TempFile(d.ref.path, "dir-put-blob")
 	if err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	succeeded := false
 	defer func() {
@@ -59,29 +69,48 @@ func (d *dirImageDestination) PutBlob(stream io.Reader, digest string, expectedS
 		}
 	}()
 
-	h := sha256.New()
-	tee := io.TeeReader(stream, h)
+	digester := digest.Canonical.New()
+	tee := io.TeeReader(stream, digester.Hash())
 
 	size, err := io.Copy(blobFile, tee)
 	if err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
-	computedDigest := hex.EncodeToString(h.Sum(nil))
-	if expectedSize != -1 && size != expectedSize {
-		return "", -1, fmt.Errorf("Size mismatch when copying %s, expected %d, got %d", computedDigest, expectedSize, size)
+	computedDigest := digester.Digest()
+	if inputInfo.Size != -1 && size != inputInfo.Size {
+		return types.BlobInfo{}, fmt.Errorf("Size mismatch when copying %s, expected %d, got %d", computedDigest, inputInfo.Size, size)
 	}
 	if err := blobFile.Sync(); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	if err := blobFile.Chmod(0644); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	blobPath := d.ref.layerPath(computedDigest)
 	if err := os.Rename(blobFile.Name(), blobPath); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	succeeded = true
-	return "sha256:" + computedDigest, size, nil
+	return types.BlobInfo{Digest: computedDigest, Size: size}, nil
+}
+
+func (d *dirImageDestination) HasBlob(info types.BlobInfo) (bool, int64, error) {
+	if info.Digest == "" {
+		return false, -1, fmt.Errorf(`"Can not check for a blob with unknown digest`)
+	}
+	blobPath := d.ref.layerPath(info.Digest)
+	finfo, err := os.Stat(blobPath)
+	if err != nil && os.IsNotExist(err) {
+		return false, -1, types.ErrBlobNotFound
+	}
+	if err != nil {
+		return false, -1, err
+	}
+	return true, finfo.Size(), nil
+}
+
+func (d *dirImageDestination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
+	return info, nil
 }
 
 func (d *dirImageDestination) PutManifest(manifest []byte) error {

vendor/src/github.com/containers/image/directory/directory_src.go

@@ -1,11 +1,14 @@
 package directory
 
 import (
+	"fmt"
 	"io"
 	"io/ioutil"
 	"os"
 
+	"github.com/containers/image/manifest"
 	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
 )
 
 type dirImageSource struct {
@@ -28,18 +31,23 @@ func (s *dirImageSource) Reference() types.ImageReference {
 func (s *dirImageSource) Close() {
 }
 
-// it's up to the caller to determine the MIME type of the returned manifest's bytes
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
 func (s *dirImageSource) GetManifest() ([]byte, string, error) {
 	m, err := ioutil.ReadFile(s.ref.manifestPath())
 	if err != nil {
 		return nil, "", err
 	}
-	return m, "", err
+	return m, manifest.GuessMIMEType(m), err
+}
+
+func (s *dirImageSource) GetTargetManifest(digest digest.Digest) ([]byte, string, error) {
+	return nil, "", fmt.Errorf(`Getting target manifest not supported by "dir:"`)
 }
 
 // GetBlob returns a stream for the specified blob, and the blob’s size (or -1 if unknown).
-func (s *dirImageSource) GetBlob(digest string) (io.ReadCloser, int64, error) {
-	r, err := os.Open(s.ref.layerPath(digest))
+func (s *dirImageSource) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
+	r, err := os.Open(s.ref.layerPath(info.Digest))
 	if err != nil {
 		return nil, 0, nil
 	}

vendor/src/github.com/containers/image/directory/directory_transport.go

@@ -7,9 +7,10 @@ import (
 	"strings"
 
 	"github.com/containers/image/directory/explicitfilepath"
+	"github.com/containers/image/docker/reference"
 	"github.com/containers/image/image"
 	"github.com/containers/image/types"
-	"github.com/docker/docker/reference"
+	"github.com/docker/distribution/digest"
 )
 
 // Transport is an ImageTransport for directory paths.
@@ -127,11 +128,13 @@ func (ref dirReference) PolicyConfigurationNamespaces() []string {
 	return res
 }
 
-// NewImage returns a types.Image for this reference.
+// NewImage returns a types.Image for this reference, possibly specialized for this ImageTransport.
 // The caller must call .Close() on the returned Image.
+// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage.
 func (ref dirReference) NewImage(ctx *types.SystemContext) (types.Image, error) {
 	src := newImageSource(ref)
-	return image.FromSource(src), nil
+	return image.FromSource(src)
 }
 
 // NewImageSource returns a types.ImageSource for this reference,
@@ -159,9 +162,9 @@ func (ref dirReference) manifestPath() string {
 }
 
 // layerPath returns a path for a layer tarball within a directory using our conventions.
-func (ref dirReference) layerPath(digest string) string {
+func (ref dirReference) layerPath(digest digest.Digest) string {
 	// FIXME: Should we keep the digest identification?
-	return filepath.Join(ref.path, strings.TrimPrefix(digest, "sha256:")+".tar")
+	return filepath.Join(ref.path, digest.Hex()+".tar")
 }
 
 // signaturePath returns a path for a signature within a directory using our conventions.

vendor/src/github.com/containers/image/docker/daemon/daemon_dest.go

@@ -0,0 +1,312 @@
+package daemon
+
+import (
+	"archive/tar"
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"time"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+	"github.com/docker/engine-api/client"
+	"golang.org/x/net/context"
+)
+
+type daemonImageDestination struct {
+	ref            daemonReference
+	namedTaggedRef reference.NamedTagged // Strictly speaking redundant with ref above; having the field makes it structurally impossible for later users to fail.
+	// For talking to imageLoadGoroutine
+	goroutineCancel context.CancelFunc
+	statusChannel   <-chan error
+	writer          *io.PipeWriter
+	tar             *tar.Writer
+	// Other state
+	committed bool                             // writer has been closed
+	blobs     map[digest.Digest]types.BlobInfo // list of already-sent blobs
+}
+
+// newImageDestination returns a types.ImageDestination for the specified image reference.
+func newImageDestination(systemCtx *types.SystemContext, ref daemonReference) (types.ImageDestination, error) {
+	if ref.ref == nil {
+		return nil, fmt.Errorf("Invalid destination docker-daemon:%s: a destination must be a name:tag", ref.StringWithinTransport())
+	}
+	namedTaggedRef, ok := ref.ref.(reference.NamedTagged)
+	if !ok {
+		return nil, fmt.Errorf("Invalid destination docker-daemon:%s: a destination must be a name:tag", ref.StringWithinTransport())
+	}
+
+	c, err := client.NewClient(client.DefaultDockerHost, "1.22", nil, nil) // FIXME: overridable host
+	if err != nil {
+		return nil, fmt.Errorf("Error initializing docker engine client: %v", err)
+	}
+
+	reader, writer := io.Pipe()
+	// Commit() may never be called, so we may never read from this channel; so, make this buffered to allow imageLoadGoroutine to write status and terminate even if we never read it.
+	statusChannel := make(chan error, 1)
+
+	ctx, goroutineCancel := context.WithCancel(context.Background())
+	go imageLoadGoroutine(ctx, c, reader, statusChannel)
+
+	return &daemonImageDestination{
+		ref:             ref,
+		namedTaggedRef:  namedTaggedRef,
+		goroutineCancel: goroutineCancel,
+		statusChannel:   statusChannel,
+		writer:          writer,
+		tar:             tar.NewWriter(writer),
+		committed:       false,
+		blobs:           make(map[digest.Digest]types.BlobInfo),
+	}, nil
+}
+
+// imageLoadGoroutine accepts tar stream on reader, sends it to c, and reports error or success by writing to statusChannel
+func imageLoadGoroutine(ctx context.Context, c *client.Client, reader *io.PipeReader, statusChannel chan<- error) {
+	err := errors.New("Internal error: unexpected panic in imageLoadGoroutine")
+	defer func() {
+		logrus.Debugf("docker-daemon: sending done, status %v", err)
+		statusChannel <- err
+	}()
+	defer func() {
+		if err == nil {
+			reader.Close()
+		} else {
+			reader.CloseWithError(err)
+		}
+	}()
+
+	resp, err := c.ImageLoad(ctx, reader, true)
+	if err != nil {
+		err = fmt.Errorf("Error saving image to docker engine: %v", err)
+		return
+	}
+	defer resp.Body.Close()
+}
+
+// Close removes resources associated with an initialized ImageDestination, if any.
+func (d *daemonImageDestination) Close() {
+	if !d.committed {
+		logrus.Debugf("docker-daemon: Closing tar stream to abort loading")
+		// In principle, goroutineCancel() should abort the HTTP request and stop the process from continuing.
+		// In practice, though, https://github.com/docker/engine-api/blob/master/client/transport/cancellable/cancellable.go
+		// currently just runs the HTTP request to completion in a goroutine, and returns early if the context is canceled
+		// without terminating the HTTP request at all.  So we need this CloseWithError to terminate sending the HTTP request Body
+		// immediately, and hopefully, through terminating the sending which uses "Transfer-Encoding: chunked"" without sending
+		// the terminating zero-length chunk, prevent the docker daemon from processing the tar stream at all.
+		// Whether that works or not, closing the PipeWriter seems desirable in any case.
+		d.writer.CloseWithError(errors.New("Aborting upload, daemonImageDestination closed without a previous .Commit()"))
+	}
+	d.goroutineCancel()
+}
+
+// Reference returns the reference used to set up this destination.  Note that this should directly correspond to user's intent,
+// e.g. it should use the public hostname instead of the result of resolving CNAMEs or following redirects.
+func (d *daemonImageDestination) Reference() types.ImageReference {
+	return d.ref
+}
+
+// SupportedManifestMIMETypes tells which manifest mime types the destination supports
+// If an empty slice or nil it's returned, then any mime type can be tried to upload
+func (d *daemonImageDestination) SupportedManifestMIMETypes() []string {
+	return []string{
+		manifest.DockerV2Schema2MediaType, // We rely on the types.Image.UpdatedImage schema conversion capabilities.
+	}
+}
+
+// SupportsSignatures returns an error (to be displayed to the user) if the destination certainly can't store signatures.
+// Note: It is still possible for PutSignatures to fail if SupportsSignatures returns nil.
+func (d *daemonImageDestination) SupportsSignatures() error {
+	return fmt.Errorf("Storing signatures for docker-daemon: destinations is not supported")
+}
+
+// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination.
+func (d *daemonImageDestination) ShouldCompressLayers() bool {
+	return false
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (d *daemonImageDestination) AcceptsForeignLayerURLs() bool {
+	return false
+}
+
+// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+// inputInfo.Size is the expected length of stream, if known.
+// WARNING: The contents of stream are being verified on the fly.  Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
+// to any other readers for download using the supplied digest.
+// If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlob MUST 1) fail, and 2) delete any data stored so far.
+func (d *daemonImageDestination) PutBlob(stream io.Reader, inputInfo types.BlobInfo) (types.BlobInfo, error) {
+	if ok, size, err := d.HasBlob(inputInfo); err == nil && ok {
+		return types.BlobInfo{Digest: inputInfo.Digest, Size: size}, nil
+	}
+
+	if inputInfo.Size == -1 { // Ouch, we need to stream the blob into a temporary file just to determine the size.
+		logrus.Debugf("docker-daemon: input with unknown size, streaming to disk first…")
+		streamCopy, err := ioutil.TempFile(temporaryDirectoryForBigFiles, "docker-daemon-blob")
+		if err != nil {
+			return types.BlobInfo{}, err
+		}
+		defer os.Remove(streamCopy.Name())
+		defer streamCopy.Close()
+
+		size, err := io.Copy(streamCopy, stream)
+		if err != nil {
+			return types.BlobInfo{}, err
+		}
+		_, err = streamCopy.Seek(0, os.SEEK_SET)
+		if err != nil {
+			return types.BlobInfo{}, err
+		}
+		inputInfo.Size = size // inputInfo is a struct, so we are only modifying our copy.
+		stream = streamCopy
+		logrus.Debugf("… streaming done")
+	}
+
+	digester := digest.Canonical.New()
+	tee := io.TeeReader(stream, digester.Hash())
+	if err := d.sendFile(inputInfo.Digest.String(), inputInfo.Size, tee); err != nil {
+		return types.BlobInfo{}, err
+	}
+	d.blobs[inputInfo.Digest] = types.BlobInfo{Digest: digester.Digest(), Size: inputInfo.Size}
+	return types.BlobInfo{Digest: digester.Digest(), Size: inputInfo.Size}, nil
+}
+
+func (d *daemonImageDestination) HasBlob(info types.BlobInfo) (bool, int64, error) {
+	if info.Digest == "" {
+		return false, -1, fmt.Errorf(`"Can not check for a blob with unknown digest`)
+	}
+	if blob, ok := d.blobs[info.Digest]; ok {
+		return true, blob.Size, nil
+	}
+	return false, -1, types.ErrBlobNotFound
+}
+
+func (d *daemonImageDestination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
+	return info, nil
+}
+
+func (d *daemonImageDestination) PutManifest(m []byte) error {
+	var man schema2Manifest
+	if err := json.Unmarshal(m, &man); err != nil {
+		return fmt.Errorf("Error parsing manifest: %v", err)
+	}
+	if man.SchemaVersion != 2 || man.MediaType != manifest.DockerV2Schema2MediaType {
+		return fmt.Errorf("Unsupported manifest type, need a Docker schema 2 manifest")
+	}
+
+	layerPaths := []string{}
+	for _, l := range man.Layers {
+		layerPaths = append(layerPaths, l.Digest.String())
+	}
+
+	// For github.com/docker/docker consumers, this works just as well as
+	//   refString := d.namedTaggedRef.String()  [i.e. d.ref.ref.String()]
+	// because when reading the RepoTags strings, github.com/docker/docker/reference
+	// normalizes both of them to the same value.
+	//
+	// Doing it this way to include the normalized-out `docker.io[/library]` does make
+	// a difference for github.com/projectatomic/docker consumers, with the
+	// “Add --add-registry and --block-registry options to docker daemon” patch.
+	// These consumers treat reference strings which include a hostname and reference
+	// strings without a hostname differently.
+	//
+	// Using the host name here is more explicit about the intent, and it has the same
+	// effect as (docker pull) in projectatomic/docker, which tags the result using
+	// a hostname-qualified reference.
+	// See https://github.com/containers/image/issues/72 for a more detailed
+	// analysis and explanation.
+	refString := fmt.Sprintf("%s:%s", d.namedTaggedRef.FullName(), d.namedTaggedRef.Tag())
+
+	items := []manifestItem{{
+		Config:       man.Config.Digest.String(),
+		RepoTags:     []string{refString},
+		Layers:       layerPaths,
+		Parent:       "",
+		LayerSources: nil,
+	}}
+	itemsBytes, err := json.Marshal(&items)
+	if err != nil {
+		return err
+	}
+
+	// FIXME? Do we also need to support the legacy format?
+	return d.sendFile(manifestFileName, int64(len(itemsBytes)), bytes.NewReader(itemsBytes))
+}
+
+type tarFI struct {
+	path string
+	size int64
+}
+
+func (t *tarFI) Name() string {
+	return t.path
+}
+func (t *tarFI) Size() int64 {
+	return t.size
+}
+func (t *tarFI) Mode() os.FileMode {
+	return 0444
+}
+func (t *tarFI) ModTime() time.Time {
+	return time.Unix(0, 0)
+}
+func (t *tarFI) IsDir() bool {
+	return false
+}
+func (t *tarFI) Sys() interface{} {
+	return nil
+}
+
+// sendFile sends a file into the tar stream.
+func (d *daemonImageDestination) sendFile(path string, expectedSize int64, stream io.Reader) error {
+	hdr, err := tar.FileInfoHeader(&tarFI{path: path, size: expectedSize}, "")
+	if err != nil {
+		return nil
+	}
+	logrus.Debugf("Sending as tar file %s", path)
+	if err := d.tar.WriteHeader(hdr); err != nil {
+		return err
+	}
+	size, err := io.Copy(d.tar, stream)
+	if err != nil {
+		return err
+	}
+	if size != expectedSize {
+		return fmt.Errorf("Size mismatch when copying %s, expected %d, got %d", path, expectedSize, size)
+	}
+	return nil
+}
+
+func (d *daemonImageDestination) PutSignatures(signatures [][]byte) error {
+	if len(signatures) != 0 {
+		return fmt.Errorf("Storing signatures for docker-daemon: destinations is not supported")
+	}
+	return nil
+}
+
+// Commit marks the process of storing the image as successful and asks for the image to be persisted.
+// WARNING: This does not have any transactional semantics:
+// - Uploaded data MAY be visible to others before Commit() is called
+// - Uploaded data MAY be removed or MAY remain around if Close() is called without Commit() (i.e. rollback is allowed but not guaranteed)
+func (d *daemonImageDestination) Commit() error {
+	logrus.Debugf("docker-daemon: Closing tar stream")
+	if err := d.tar.Close(); err != nil {
+		return err
+	}
+	if err := d.writer.Close(); err != nil {
+		return err
+	}
+	d.committed = true // We may still fail, but we are done sending to imageLoadGoroutine.
+
+	logrus.Debugf("docker-daemon: Waiting for status")
+	err := <-d.statusChannel
+	return err
+}

vendor/src/github.com/containers/image/docker/daemon/daemon_src.go

@@ -0,0 +1,361 @@
+package daemon
+
+import (
+	"archive/tar"
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+	"github.com/docker/engine-api/client"
+	"golang.org/x/net/context"
+)
+
+const temporaryDirectoryForBigFiles = "/var/tmp" // Do not use the system default of os.TempDir(), usually /tmp, because with systemd it could be a tmpfs.
+
+type daemonImageSource struct {
+	ref         daemonReference
+	tarCopyPath string
+	// The following data is only available after ensureCachedDataIsPresent() succeeds
+	tarManifest       *manifestItem // nil if not available yet.
+	configBytes       []byte
+	configDigest      digest.Digest
+	orderedDiffIDList []diffID
+	knownLayers       map[diffID]*layerInfo
+	// Other state
+	generatedManifest []byte // Private cache for GetManifest(), nil if not set yet.
+}
+
+type layerInfo struct {
+	path string
+	size int64
+}
+
+// newImageSource returns a types.ImageSource for the specified image reference.
+// The caller must call .Close() on the returned ImageSource.
+//
+// It would be great if we were able to stream the input tar as it is being
+// sent; but Docker sends the top-level manifest, which determines which paths
+// to look for, at the end, so in we will need to seek back and re-read, several times.
+// (We could, perhaps, expect an exact sequence, assume that the first plaintext file
+// is the config, and that the following len(RootFS) files are the layers, but that feels
+// way too brittle.)
+func newImageSource(ctx *types.SystemContext, ref daemonReference) (types.ImageSource, error) {
+	c, err := client.NewClient(client.DefaultDockerHost, "1.22", nil, nil) // FIXME: overridable host
+	if err != nil {
+		return nil, fmt.Errorf("Error initializing docker engine client: %v", err)
+	}
+	// Per NewReference(), ref.StringWithinTransport() is either an image ID (config digest), or a !reference.NameOnly() reference.
+	// Either way ImageSave should create a tarball with exactly one image.
+	inputStream, err := c.ImageSave(context.TODO(), []string{ref.StringWithinTransport()})
+	if err != nil {
+		return nil, fmt.Errorf("Error loading image from docker engine: %v", err)
+	}
+	defer inputStream.Close()
+
+	// FIXME: use SystemContext here.
+	tarCopyFile, err := ioutil.TempFile(temporaryDirectoryForBigFiles, "docker-daemon-tar")
+	if err != nil {
+		return nil, err
+	}
+	defer tarCopyFile.Close()
+
+	succeeded := false
+	defer func() {
+		if !succeeded {
+			os.Remove(tarCopyFile.Name())
+		}
+	}()
+
+	if _, err := io.Copy(tarCopyFile, inputStream); err != nil {
+		return nil, err
+	}
+
+	succeeded = true
+	return &daemonImageSource{
+		ref:         ref,
+		tarCopyPath: tarCopyFile.Name(),
+	}, nil
+}
+
+// Reference returns the reference used to set up this source, _as specified by the user_
+// (not as the image itself, or its underlying storage, claims).  This can be used e.g. to determine which public keys are trusted for this image.
+func (s *daemonImageSource) Reference() types.ImageReference {
+	return s.ref
+}
+
+// Close removes resources associated with an initialized ImageSource, if any.
+func (s *daemonImageSource) Close() {
+	_ = os.Remove(s.tarCopyPath)
+}
+
+// tarReadCloser is a way to close the backing file of a tar.Reader when the user no longer needs the tar component.
+type tarReadCloser struct {
+	*tar.Reader
+	backingFile *os.File
+}
+
+func (t *tarReadCloser) Close() error {
+	return t.backingFile.Close()
+}
+
+// openTarComponent returns a ReadCloser for the specific file within the archive.
+// This is linear scan; we assume that the tar file will have a fairly small amount of files (~layers),
+// and that filesystem caching will make the repeated seeking over the (uncompressed) tarCopyPath cheap enough.
+// The caller should call .Close() on the returned stream.
+func (s *daemonImageSource) openTarComponent(componentPath string) (io.ReadCloser, error) {
+	f, err := os.Open(s.tarCopyPath)
+	if err != nil {
+		return nil, err
+	}
+	succeeded := false
+	defer func() {
+		if !succeeded {
+			f.Close()
+		}
+	}()
+
+	tarReader, header, err := findTarComponent(f, componentPath)
+	if err != nil {
+		return nil, err
+	}
+	if header == nil {
+		return nil, os.ErrNotExist
+	}
+	if header.FileInfo().Mode()&os.ModeType == os.ModeSymlink { // FIXME: untested
+		// We follow only one symlink; so no loops are possible.
+		if _, err := f.Seek(0, os.SEEK_SET); err != nil {
+			return nil, err
+		}
+		// The new path could easily point "outside" the archive, but we only compare it to existing tar headers without extracting the archive,
+		// so we don't care.
+		tarReader, header, err = findTarComponent(f, path.Join(path.Dir(componentPath), header.Linkname))
+		if err != nil {
+			return nil, err
+		}
+		if header == nil {
+			return nil, os.ErrNotExist
+		}
+	}
+
+	if !header.FileInfo().Mode().IsRegular() {
+		return nil, fmt.Errorf("Error reading tar archive component %s: not a regular file", header.Name)
+	}
+	succeeded = true
+	return &tarReadCloser{Reader: tarReader, backingFile: f}, nil
+}
+
+// findTarComponent returns a header and a reader matching path within inputFile,
+// or (nil, nil, nil) if not found.
+func findTarComponent(inputFile io.Reader, path string) (*tar.Reader, *tar.Header, error) {
+	t := tar.NewReader(inputFile)
+	for {
+		h, err := t.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, nil, err
+		}
+		if h.Name == path {
+			return t, h, nil
+		}
+	}
+	return nil, nil, nil
+}
+
+// readTarComponent returns full contents of componentPath.
+func (s *daemonImageSource) readTarComponent(path string) ([]byte, error) {
+	file, err := s.openTarComponent(path)
+	if err != nil {
+		return nil, fmt.Errorf("Error loading tar component %s: %v", path, err)
+	}
+	defer file.Close()
+	bytes, err := ioutil.ReadAll(file)
+	if err != nil {
+		return nil, err
+	}
+	return bytes, nil
+}
+
+// ensureCachedDataIsPresent loads data necessary for any of the public accessors.
+func (s *daemonImageSource) ensureCachedDataIsPresent() error {
+	if s.tarManifest != nil {
+		return nil
+	}
+
+	// Read and parse manifest.json
+	tarManifest, err := s.loadTarManifest()
+	if err != nil {
+		return err
+	}
+
+	// Read and parse config.
+	configBytes, err := s.readTarComponent(tarManifest.Config)
+	if err != nil {
+		return err
+	}
+	var parsedConfig dockerImage // Most fields ommitted, we only care about layer DiffIDs.
+	if err := json.Unmarshal(configBytes, &parsedConfig); err != nil {
+		return fmt.Errorf("Error decoding tar config %s: %v", tarManifest.Config, err)
+	}
+
+	knownLayers, err := s.prepareLayerData(tarManifest, &parsedConfig)
+	if err != nil {
+		return err
+	}
+
+	// Success; commit.
+	s.tarManifest = tarManifest
+	s.configBytes = configBytes
+	s.configDigest = digest.FromBytes(configBytes)
+	s.orderedDiffIDList = parsedConfig.RootFS.DiffIDs
+	s.knownLayers = knownLayers
+	return nil
+}
+
+// loadTarManifest loads and decodes the manifest.json.
+func (s *daemonImageSource) loadTarManifest() (*manifestItem, error) {
+	// FIXME? Do we need to deal with the legacy format?
+	bytes, err := s.readTarComponent(manifestFileName)
+	if err != nil {
+		return nil, err
+	}
+	var items []manifestItem
+	if err := json.Unmarshal(bytes, &items); err != nil {
+		return nil, fmt.Errorf("Error decoding tar manifest.json: %v", err)
+	}
+	if len(items) != 1 {
+		return nil, fmt.Errorf("Unexpected tar manifest.json: expected 1 item, got %d", len(items))
+	}
+	return &items[0], nil
+}
+
+func (s *daemonImageSource) prepareLayerData(tarManifest *manifestItem, parsedConfig *dockerImage) (map[diffID]*layerInfo, error) {
+	// Collect layer data available in manifest and config.
+	if len(tarManifest.Layers) != len(parsedConfig.RootFS.DiffIDs) {
+		return nil, fmt.Errorf("Inconsistent layer count: %d in manifest, %d in config", len(tarManifest.Layers), len(parsedConfig.RootFS.DiffIDs))
+	}
+	knownLayers := map[diffID]*layerInfo{}
+	unknownLayerSizes := map[string]*layerInfo{} // Points into knownLayers, a "to do list" of items with unknown sizes.
+	for i, diffID := range parsedConfig.RootFS.DiffIDs {
+		if _, ok := knownLayers[diffID]; ok {
+			// Apparently it really can happen that a single image contains the same layer diff more than once.
+			// In that case, the diffID validation ensures that both layers truly are the same, and it should not matter
+			// which of the tarManifest.Layers paths is used; (docker save) actually makes the duplicates symlinks to the original.
+			continue
+		}
+		layerPath := tarManifest.Layers[i]
+		if _, ok := unknownLayerSizes[layerPath]; ok {
+			return nil, fmt.Errorf("Layer tarfile %s used for two different DiffID values", layerPath)
+		}
+		li := &layerInfo{ // A new element in each iteration
+			path: layerPath,
+			size: -1,
+		}
+		knownLayers[diffID] = li
+		unknownLayerSizes[layerPath] = li
+	}
+
+	// Scan the tar file to collect layer sizes.
+	file, err := os.Open(s.tarCopyPath)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+	t := tar.NewReader(file)
+	for {
+		h, err := t.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, err
+		}
+		if li, ok := unknownLayerSizes[h.Name]; ok {
+			li.size = h.Size
+			delete(unknownLayerSizes, h.Name)
+		}
+	}
+	if len(unknownLayerSizes) != 0 {
+		return nil, fmt.Errorf("Some layer tarfiles are missing in the tarball") // This could do with a better error reporting, if this ever happened in practice.
+	}
+
+	return knownLayers, nil
+}
+
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
+func (s *daemonImageSource) GetManifest() ([]byte, string, error) {
+	if s.generatedManifest == nil {
+		if err := s.ensureCachedDataIsPresent(); err != nil {
+			return nil, "", err
+		}
+		m := schema2Manifest{
+			SchemaVersion: 2,
+			MediaType:     manifest.DockerV2Schema2MediaType,
+			Config: distributionDescriptor{
+				MediaType: manifest.DockerV2Schema2ConfigMediaType,
+				Size:      int64(len(s.configBytes)),
+				Digest:    s.configDigest,
+			},
+			Layers: []distributionDescriptor{},
+		}
+		for _, diffID := range s.orderedDiffIDList {
+			li, ok := s.knownLayers[diffID]
+			if !ok {
+				return nil, "", fmt.Errorf("Internal inconsistency: Information about layer %s missing", diffID)
+			}
+			m.Layers = append(m.Layers, distributionDescriptor{
+				Digest:    digest.Digest(diffID), // diffID is a digest of the uncompressed tarball
+				MediaType: manifest.DockerV2Schema2LayerMediaType,
+				Size:      li.size,
+			})
+		}
+		manifestBytes, err := json.Marshal(&m)
+		if err != nil {
+			return nil, "", err
+		}
+		s.generatedManifest = manifestBytes
+	}
+	return s.generatedManifest, manifest.DockerV2Schema2MediaType, nil
+}
+
+// GetTargetManifest returns an image's manifest given a digest. This is mainly used to retrieve a single image's manifest
+// out of a manifest list.
+func (s *daemonImageSource) GetTargetManifest(digest digest.Digest) ([]byte, string, error) {
+	// How did we even get here? GetManifest() above has returned a manifest.DockerV2Schema2MediaType.
+	return nil, "", fmt.Errorf(`Manifest lists are not supported by "docker-daemon:"`)
+}
+
+// GetBlob returns a stream for the specified blob, and the blob’s size (or -1 if unknown).
+func (s *daemonImageSource) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
+	if err := s.ensureCachedDataIsPresent(); err != nil {
+		return nil, 0, err
+	}
+
+	if info.Digest == s.configDigest { // FIXME? Implement a more general algorithm matching instead of assuming sha256.
+		return ioutil.NopCloser(bytes.NewReader(s.configBytes)), int64(len(s.configBytes)), nil
+	}
+
+	if li, ok := s.knownLayers[diffID(info.Digest)]; ok { // diffID is a digest of the uncompressed tarball,
+		stream, err := s.openTarComponent(li.path)
+		if err != nil {
+			return nil, 0, err
+		}
+		return stream, li.size, nil
+	}
+
+	return nil, 0, fmt.Errorf("Unknown blob %s", info.Digest)
+}
+
+// GetSignatures returns the image's signatures.  It may use a remote (= slow) service.
+func (s *daemonImageSource) GetSignatures() ([][]byte, error) {
+	return [][]byte{}, nil
+}

vendor/src/github.com/containers/image/docker/daemon/daemon_transport.go

@@ -0,0 +1,179 @@
+package daemon
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/image"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+)
+
+// Transport is an ImageTransport for images managed by a local Docker daemon.
+var Transport = daemonTransport{}
+
+type daemonTransport struct{}
+
+// Name returns the name of the transport, which must be unique among other transports.
+func (t daemonTransport) Name() string {
+	return "docker-daemon"
+}
+
+// ParseReference converts a string, which should not start with the ImageTransport.Name prefix, into an ImageReference.
+func (t daemonTransport) ParseReference(reference string) (types.ImageReference, error) {
+	return ParseReference(reference)
+}
+
+// ValidatePolicyConfigurationScope checks that scope is a valid name for a signature.PolicyTransportScopes keys
+// (i.e. a valid PolicyConfigurationIdentity() or PolicyConfigurationNamespaces() return value).
+// It is acceptable to allow an invalid value which will never be matched, it can "only" cause user confusion.
+// scope passed to this function will not be "", that value is always allowed.
+func (t daemonTransport) ValidatePolicyConfigurationScope(scope string) error {
+	// See the explanation in daemonReference.PolicyConfigurationIdentity.
+	return errors.New(`docker-daemon: does not support any scopes except the default "" one`)
+}
+
+// daemonReference is an ImageReference for images managed by a local Docker daemon
+// Exactly one of id and ref can be set.
+// For daemonImageSource, both id and ref are acceptable, ref must not be a NameOnly (interpreted as all tags in that repository by the daemon)
+// For daemonImageDestination, it must be a ref, which is NamedTagged.
+// (We could, in principle, also allow storing images without tagging them, and the user would have to refer to them using the docker image ID = config digest.
+//  Using the config digest requires the caller to parse the manifest themselves, which is very cumbersome; so, for now, we don’t bother.)
+type daemonReference struct {
+	id  digest.Digest
+	ref reference.Named // !reference.IsNameOnly
+}
+
+// ParseReference converts a string, which should not start with the ImageTransport.Name prefix, into an ImageReference.
+func ParseReference(refString string) (types.ImageReference, error) {
+	// This is intended to be compatible with reference.ParseIDOrReference, but more strict about refusing some of the ambiguous cases.
+	// In particular, this rejects unprefixed digest values (64 hex chars), and sha256 digest prefixes (sha256:fewer-than-64-hex-chars).
+
+	// digest:hexstring is structurally the same as a reponame:tag (meaning docker.io/library/reponame:tag).
+	// reference.ParseIDOrReference interprets such strings as digests.
+	if dgst, err := digest.ParseDigest(refString); err == nil {
+		// The daemon explicitly refuses to tag images with a reponame equal to digest.Canonical - but _only_ this digest name.
+		// Other digest references are ambiguous, so refuse them.
+		if dgst.Algorithm() != digest.Canonical {
+			return nil, fmt.Errorf("Invalid docker-daemon: reference %s: only digest algorithm %s accepted", refString, digest.Canonical)
+		}
+		return NewReference(dgst, nil)
+	}
+
+	ref, err := reference.ParseNamed(refString) // This also rejects unprefixed digest values
+	if err != nil {
+		return nil, err
+	}
+	if ref.Name() == digest.Canonical.String() {
+		return nil, fmt.Errorf("Invalid docker-daemon: reference %s: The %s repository name is reserved for (non-shortened) digest references", refString, digest.Canonical)
+	}
+	return NewReference("", ref)
+}
+
+// NewReference returns a docker-daemon reference for either the supplied image ID (config digest) or the supplied reference (which must satisfy !reference.IsNameOnly)
+func NewReference(id digest.Digest, ref reference.Named) (types.ImageReference, error) {
+	if id != "" && ref != nil {
+		return nil, errors.New("docker-daemon: reference must not have an image ID and a reference string specified at the same time")
+	}
+	if ref != nil {
+		if reference.IsNameOnly(ref) {
+			return nil, fmt.Errorf("docker-daemon: reference %s has neither a tag nor a digest", ref.String())
+		}
+		// A github.com/distribution/reference value can have a tag and a digest at the same time!
+		// docker/reference does not handle that, so fail.
+		_, isTagged := ref.(reference.NamedTagged)
+		_, isDigested := ref.(reference.Canonical)
+		if isTagged && isDigested {
+			return nil, fmt.Errorf("docker-daemon: references with both a tag and digest are currently not supported")
+		}
+	}
+	return daemonReference{
+		id:  id,
+		ref: ref,
+	}, nil
+}
+
+func (ref daemonReference) Transport() types.ImageTransport {
+	return Transport
+}
+
+// StringWithinTransport returns a string representation of the reference, which MUST be such that
+// reference.Transport().ParseReference(reference.StringWithinTransport()) returns an equivalent reference.
+// NOTE: The returned string is not promised to be equal to the original input to ParseReference;
+// e.g. default attribute values omitted by the user may be filled in in the return value, or vice versa.
+// WARNING: Do not use the return value in the UI to describe an image, it does not contain the Transport().Name() prefix;
+// instead, see transports.ImageName().
+func (ref daemonReference) StringWithinTransport() string {
+	switch {
+	case ref.id != "":
+		return ref.id.String()
+	case ref.ref != nil:
+		return ref.ref.String()
+	default: // Coverage: Should never happen, NewReference above should refuse such values.
+		panic("Internal inconsistency: daemonReference has empty id and nil ref")
+	}
+}
+
+// DockerReference returns a Docker reference associated with this reference
+// (fully explicit, i.e. !reference.IsNameOnly, but reflecting user intent,
+// not e.g. after redirect or alias processing), or nil if unknown/not applicable.
+func (ref daemonReference) DockerReference() reference.Named {
+	return ref.ref // May be nil
+}
+
+// PolicyConfigurationIdentity returns a string representation of the reference, suitable for policy lookup.
+// This MUST reflect user intent, not e.g. after processing of third-party redirects or aliases;
+// The value SHOULD be fully explicit about its semantics, with no hidden defaults, AND canonical
+// (i.e. various references with exactly the same semantics should return the same configuration identity)
+// It is fine for the return value to be equal to StringWithinTransport(), and it is desirable but
+// not required/guaranteed that it will be a valid input to Transport().ParseReference().
+// Returns "" if configuration identities for these references are not supported.
+func (ref daemonReference) PolicyConfigurationIdentity() string {
+	// We must allow referring to images in the daemon by image ID, otherwise untagged images would not be accessible.
+	// But the existence of image IDs means that we can’t truly well namespace the input; the untagged images would have to fall into the default policy,
+	// which can be unexpected.  So, punt.
+	return "" // This still allows using the default "" scope to define a policy for this transport.
+}
+
+// PolicyConfigurationNamespaces returns a list of other policy configuration namespaces to search
+// for if explicit configuration for PolicyConfigurationIdentity() is not set.  The list will be processed
+// in order, terminating on first match, and an implicit "" is always checked at the end.
+// It is STRONGLY recommended for the first element, if any, to be a prefix of PolicyConfigurationIdentity(),
+// and each following element to be a prefix of the element preceding it.
+func (ref daemonReference) PolicyConfigurationNamespaces() []string {
+	// See the explanation in daemonReference.PolicyConfigurationIdentity.
+	return []string{}
+}
+
+// NewImage returns a types.Image for this reference.
+// The caller must call .Close() on the returned Image.
+func (ref daemonReference) NewImage(ctx *types.SystemContext) (types.Image, error) {
+	src, err := newImageSource(ctx, ref)
+	if err != nil {
+		return nil, err
+	}
+	return image.FromSource(src)
+}
+
+// NewImageSource returns a types.ImageSource for this reference,
+// asking the backend to use a manifest from requestedManifestMIMETypes if possible.
+// nil requestedManifestMIMETypes means manifest.DefaultRequestedManifestMIMETypes.
+// The caller must call .Close() on the returned ImageSource.
+func (ref daemonReference) NewImageSource(ctx *types.SystemContext, requestedManifestMIMETypes []string) (types.ImageSource, error) {
+	return newImageSource(ctx, ref)
+}
+
+// NewImageDestination returns a types.ImageDestination for this reference.
+// The caller must call .Close() on the returned ImageDestination.
+func (ref daemonReference) NewImageDestination(ctx *types.SystemContext) (types.ImageDestination, error) {
+	return newImageDestination(ctx, ref)
+}
+
+// DeleteImage deletes the named image from the registry, if supported.
+func (ref daemonReference) DeleteImage(ctx *types.SystemContext) error {
+	// Should this just untag the image? Should this stop running containers?
+	// The semantics is not quite as clear as for remote repositories.
+	// The user can run (docker rmi) directly anyway, so, for now(?), punt instead of trying to guess what the user meant.
+	return fmt.Errorf("Deleting images not implemented for docker-daemon: images")
+}

vendor/src/github.com/containers/image/docker/daemon/daemon_types.go

@@ -0,0 +1,53 @@
+package daemon
+
+import "github.com/docker/distribution/digest"
+
+// Various data structures.
+
+// Based on github.com/docker/docker/image/tarexport/tarexport.go
+const (
+	manifestFileName = "manifest.json"
+	// legacyLayerFileName        = "layer.tar"
+	// legacyConfigFileName       = "json"
+	// legacyVersionFileName      = "VERSION"
+	// legacyRepositoriesFileName = "repositories"
+)
+
+type manifestItem struct {
+	Config       string
+	RepoTags     []string
+	Layers       []string
+	Parent       imageID                           `json:",omitempty"`
+	LayerSources map[diffID]distributionDescriptor `json:",omitempty"`
+}
+
+type imageID string
+type diffID digest.Digest
+
+// Based on github.com/docker/distribution/blobs.go
+type distributionDescriptor struct {
+	MediaType string        `json:"mediaType,omitempty"`
+	Size      int64         `json:"size,omitempty"`
+	Digest    digest.Digest `json:"digest,omitempty"`
+	URLs      []string      `json:"urls,omitempty"`
+}
+
+// Based on github.com/docker/distribution/manifest/schema2/manifest.go
+// FIXME: We are repeating this all over the place; make a public copy?
+type schema2Manifest struct {
+	SchemaVersion int                      `json:"schemaVersion"`
+	MediaType     string                   `json:"mediaType,omitempty"`
+	Config        distributionDescriptor   `json:"config"`
+	Layers        []distributionDescriptor `json:"layers"`
+}
+
+// Based on github.com/docker/docker/image/image.go
+// MOST CONTENT OMITTED AS UNNECESSARY
+type dockerImage struct {
+	RootFS *rootFS `json:"rootfs,omitempty"`
+}
+
+type rootFS struct {
+	Type    string   `json:"type"`
+	DiffIDs []diffID `json:"diff_ids,omitempty"`
+}

vendor/src/github.com/containers/image/docker/docker_client.go

@@ -4,9 +4,11 @@ import (
 	"crypto/tls"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
+	"net"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -15,7 +17,9 @@ import (
 
 	"github.com/Sirupsen/logrus"
 	"github.com/containers/image/types"
-	"github.com/docker/docker/pkg/homedir"
+	"github.com/containers/storage/pkg/homedir"
+	"github.com/docker/go-connections/sockets"
+	"github.com/docker/go-connections/tlsconfig"
 )
 
 const (
@@ -28,12 +32,17 @@ const (
 	dockerCfgObsolete = ".dockercfg"
 
 	baseURL       = "%s://%s/v2/"
+	baseURLV1     = "%s://%s/v1/_ping"
 	tagsURL       = "%s/tags/list"
 	manifestURL   = "%s/manifests/%s"
 	blobsURL      = "%s/blobs/%s"
 	blobUploadURL = "%s/blobs/uploads/"
 )
 
+// ErrV1NotSupported is returned when we're trying to talk to a
+// docker V1 registry.
+var ErrV1NotSupported = errors.New("can't talk to a V1 docker registry")
+
 // dockerClient is configuration for dealing with a single Docker registry.
 type dockerClient struct {
 	ctx             *types.SystemContext
@@ -46,6 +55,96 @@ type dockerClient struct {
 	signatureBase   signatureStorageBase
 }
 
+// this is cloned from docker/go-connections because upstream docker has changed
+// it and make deps here fails otherwise.
+// We'll drop this once we upgrade to docker 1.13.x deps.
+func serverDefault() *tls.Config {
+	return &tls.Config{
+		// Avoid fallback to SSL protocols < TLS1.0
+		MinVersion:               tls.VersionTLS10,
+		PreferServerCipherSuites: true,
+		CipherSuites:             tlsconfig.DefaultServerAcceptedCiphers,
+	}
+}
+
+func newTransport() *http.Transport {
+	direct := &net.Dialer{
+		Timeout:   30 * time.Second,
+		KeepAlive: 30 * time.Second,
+		DualStack: true,
+	}
+	tr := &http.Transport{
+		Proxy:               http.ProxyFromEnvironment,
+		Dial:                direct.Dial,
+		TLSHandshakeTimeout: 10 * time.Second,
+		// TODO(dmcgowan): Call close idle connections when complete and use keep alive
+		DisableKeepAlives: true,
+	}
+	proxyDialer, err := sockets.DialerFromEnvironment(direct)
+	if err == nil {
+		tr.Dial = proxyDialer.Dial
+	}
+	return tr
+}
+
+func setupCertificates(dir string, tlsc *tls.Config) error {
+	if dir == "" {
+		return nil
+	}
+	fs, err := ioutil.ReadDir(dir)
+	if err != nil && !os.IsNotExist(err) {
+		return err
+	}
+
+	for _, f := range fs {
+		fullPath := filepath.Join(dir, f.Name())
+		if strings.HasSuffix(f.Name(), ".crt") {
+			systemPool, err := tlsconfig.SystemCertPool()
+			if err != nil {
+				return fmt.Errorf("unable to get system cert pool: %v", err)
+			}
+			tlsc.RootCAs = systemPool
+			logrus.Debugf("crt: %s", fullPath)
+			data, err := ioutil.ReadFile(fullPath)
+			if err != nil {
+				return err
+			}
+			tlsc.RootCAs.AppendCertsFromPEM(data)
+		}
+		if strings.HasSuffix(f.Name(), ".cert") {
+			certName := f.Name()
+			keyName := certName[:len(certName)-5] + ".key"
+			logrus.Debugf("cert: %s", fullPath)
+			if !hasFile(fs, keyName) {
+				return fmt.Errorf("missing key %s for client certificate %s. Note that CA certificates should use the extension .crt", keyName, certName)
+			}
+			cert, err := tls.LoadX509KeyPair(filepath.Join(dir, certName), filepath.Join(dir, keyName))
+			if err != nil {
+				return err
+			}
+			tlsc.Certificates = append(tlsc.Certificates, cert)
+		}
+		if strings.HasSuffix(f.Name(), ".key") {
+			keyName := f.Name()
+			certName := keyName[:len(keyName)-4] + ".cert"
+			logrus.Debugf("key: %s", fullPath)
+			if !hasFile(fs, certName) {
+				return fmt.Errorf("missing client certificate %s for key %s", certName, keyName)
+			}
+		}
+	}
+	return nil
+}
+
+func hasFile(files []os.FileInfo, name string) bool {
+	for _, f := range files {
+		if f.Name() == name {
+			return true
+		}
+	}
+	return false
+}
+
 // newDockerClient returns a new dockerClient instance for refHostname (a host a specified in the Docker image reference, not canonicalized to dockerRegistry)
 // “write” specifies whether the client will be used for "write" access (in particular passed to lookaside.go:toplevelFromSection)
 func newDockerClient(ctx *types.SystemContext, ref dockerReference, write bool) (*dockerClient, error) {
@@ -53,32 +152,25 @@ func newDockerClient(ctx *types.SystemContext, ref dockerReference, write bool)
 	if registry == dockerHostname {
 		registry = dockerRegistry
 	}
-	username, password, err := getAuth(ref.ref.Hostname())
+	username, password, err := getAuth(ctx, ref.ref.Hostname())
 	if err != nil {
 		return nil, err
 	}
-	var tr *http.Transport
+	tr := newTransport()
 	if ctx != nil && (ctx.DockerCertPath != "" || ctx.DockerInsecureSkipTLSVerify) {
 		tlsc := &tls.Config{}
 
-		if ctx.DockerCertPath != "" {
-			cert, err := tls.LoadX509KeyPair(filepath.Join(ctx.DockerCertPath, "cert.pem"), filepath.Join(ctx.DockerCertPath, "key.pem"))
-			if err != nil {
-				return nil, fmt.Errorf("Error loading x509 key pair: %s", err)
-			}
-			tlsc.Certificates = append(tlsc.Certificates, cert)
+		if err := setupCertificates(ctx.DockerCertPath, tlsc); err != nil {
+			return nil, err
 		}
+
 		tlsc.InsecureSkipVerify = ctx.DockerInsecureSkipTLSVerify
-		tr = &http.Transport{
-			TLSClientConfig: tlsc,
-		}
+		tr.TLSClientConfig = tlsc
 	}
-	client := &http.Client{
-		Timeout: 1 * time.Minute,
-	}
-	if tr != nil {
-		client.Transport = tr
+	if tr.TLSClientConfig == nil {
+		tr.TLSClientConfig = serverDefault()
 	}
+	client := &http.Client{Transport: tr}
 
 	sigBase, err := configuredSignatureStorageBase(ctx, ref, write)
 	if err != nil {
@@ -108,13 +200,14 @@ func (c *dockerClient) makeRequest(method, url string, headers map[string][]stri
 	}
 
 	url = fmt.Sprintf(baseURL, c.scheme, c.registry) + url
-	return c.makeRequestToResolvedURL(method, url, headers, stream, -1)
+	return c.makeRequestToResolvedURL(method, url, headers, stream, -1, true)
 }
 
 // makeRequestToResolvedURL creates and executes a http.Request with the specified parameters, adding authentication and TLS options for the Docker client.
 // streamLen, if not -1, specifies the length of the data expected on stream.
 // makeRequest should generally be preferred.
-func (c *dockerClient) makeRequestToResolvedURL(method, url string, headers map[string][]string, stream io.Reader, streamLen int64) (*http.Response, error) {
+// TODO(runcom): too many arguments here, use a struct
+func (c *dockerClient) makeRequestToResolvedURL(method, url string, headers map[string][]string, stream io.Reader, streamLen int64, sendAuth bool) (*http.Response, error) {
 	req, err := http.NewRequest(method, url, stream)
 	if err != nil {
 		return nil, err
@@ -128,7 +221,10 @@ func (c *dockerClient) makeRequestToResolvedURL(method, url string, headers map[
 			req.Header.Add(n, hh)
 		}
 	}
-	if c.wwwAuthenticate != "" {
+	if c.ctx != nil && c.ctx.DockerRegistryUserAgent != "" {
+		req.Header.Add("User-Agent", c.ctx.DockerRegistryUserAgent)
+	}
+	if c.wwwAuthenticate != "" && sendAuth {
 		if err := c.setupRequestAuth(req); err != nil {
 			return nil, err
 		}
@@ -210,8 +306,9 @@ func (c *dockerClient) getBearerToken(realm, service, scope string) (string, err
 	if c.username != "" && c.password != "" {
 		authReq.SetBasicAuth(c.username, c.password)
 	}
-	// insecure for now to contact the external token service
-	tr := &http.Transport{TLSClientConfig: &tls.Config{InsecureSkipVerify: true}}
+	tr := newTransport()
+	// TODO(runcom): insecure for now to contact the external token service
+	tr.TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
 	client := &http.Client{Transport: tr}
 	res, err := client.Do(authReq)
 	if err != nil {
@@ -246,69 +343,70 @@ func (c *dockerClient) getBearerToken(realm, service, scope string) (string, err
 	return tokenStruct.Token, nil
 }
 
-func getAuth(hostname string) (string, string, error) {
-	// TODO(runcom): get this from *cli.Context somehow
-	//if username != "" && password != "" {
-	//return username, password, nil
-	//}
-	if hostname == dockerHostname {
-		hostname = dockerAuthRegistry
+func getAuth(ctx *types.SystemContext, registry string) (string, string, error) {
+	if ctx != nil && ctx.DockerAuthConfig != nil {
+		return ctx.DockerAuthConfig.Username, ctx.DockerAuthConfig.Password, nil
 	}
+	var dockerAuth dockerConfigFile
 	dockerCfgPath := filepath.Join(getDefaultConfigDir(".docker"), dockerCfgFileName)
 	if _, err := os.Stat(dockerCfgPath); err == nil {
 		j, err := ioutil.ReadFile(dockerCfgPath)
 		if err != nil {
 			return "", "", err
 		}
-		var dockerAuth dockerConfigFile
 		if err := json.Unmarshal(j, &dockerAuth); err != nil {
 			return "", "", err
 		}
-		// try the normal case
-		if c, ok := dockerAuth.AuthConfigs[hostname]; ok {
-			return decodeDockerAuth(c.Auth)
-		}
+
 	} else if os.IsNotExist(err) {
+		// try old config path
 		oldDockerCfgPath := filepath.Join(getDefaultConfigDir(dockerCfgObsolete))
 		if _, err := os.Stat(oldDockerCfgPath); err != nil {
-			return "", "", nil //missing file is not an error
+			if os.IsNotExist(err) {
+				return "", "", nil
+			}
+			return "", "", fmt.Errorf("%s - %v", oldDockerCfgPath, err)
 		}
+
 		j, err := ioutil.ReadFile(oldDockerCfgPath)
 		if err != nil {
 			return "", "", err
 		}
-		var dockerAuthOld map[string]dockerAuthConfigObsolete
-		if err := json.Unmarshal(j, &dockerAuthOld); err != nil {
+		if err := json.Unmarshal(j, &dockerAuth.AuthConfigs); err != nil {
 			return "", "", err
 		}
-		if c, ok := dockerAuthOld[hostname]; ok {
-			return decodeDockerAuth(c.Auth)
-		}
-	} else {
-		// if file is there but we can't stat it for any reason other
-		// than it doesn't exist then stop
+
+	} else if err != nil {
 		return "", "", fmt.Errorf("%s - %v", dockerCfgPath, err)
 	}
-	return "", "", nil
-}
 
-type apiErr struct {
-	Code    string
-	Message string
-	Detail  interface{}
+	// I'm feeling lucky
+	if c, exists := dockerAuth.AuthConfigs[registry]; exists {
+		return decodeDockerAuth(c.Auth)
+	}
+
+	// bad luck; let's normalize the entries first
+	registry = normalizeRegistry(registry)
+	normalizedAuths := map[string]dockerAuthConfig{}
+	for k, v := range dockerAuth.AuthConfigs {
+		normalizedAuths[normalizeRegistry(k)] = v
+	}
+	if c, exists := normalizedAuths[registry]; exists {
+		return decodeDockerAuth(c.Auth)
+	}
+	return "", "", nil
 }
 
 type pingResponse struct {
 	WWWAuthenticate string
 	APIVersion      string
 	scheme          string
-	errors          []apiErr
 }
 
 func (c *dockerClient) ping() (*pingResponse, error) {
 	ping := func(scheme string) (*pingResponse, error) {
 		url := fmt.Sprintf(baseURL, scheme, c.registry)
-		resp, err := c.client.Get(url)
+		resp, err := c.makeRequestToResolvedURL("GET", url, nil, nil, -1, true)
 		logrus.Debugf("Ping %s err %#v", url, err)
 		if err != nil {
 			return nil, err
@@ -322,22 +420,40 @@ func (c *dockerClient) ping() (*pingResponse, error) {
 		pr.WWWAuthenticate = resp.Header.Get("WWW-Authenticate")
 		pr.APIVersion = resp.Header.Get("Docker-Distribution-Api-Version")
 		pr.scheme = scheme
-		if resp.StatusCode == http.StatusUnauthorized {
-			type APIErrors struct {
-				Errors []apiErr
-			}
-			errs := &APIErrors{}
-			if err := json.NewDecoder(resp.Body).Decode(errs); err != nil {
-				return nil, err
-			}
-			pr.errors = errs.Errors
-		}
 		return pr, nil
 	}
 	pr, err := ping("https")
-	if err != nil && c.ctx.DockerInsecureSkipTLSVerify {
+	if err != nil && c.ctx != nil && c.ctx.DockerInsecureSkipTLSVerify {
 		pr, err = ping("http")
 	}
+	if err != nil {
+		err = fmt.Errorf("pinging docker registry returned %+v", err)
+		if c.ctx != nil && c.ctx.DockerDisableV1Ping {
+			return nil, err
+		}
+		// best effort to understand if we're talking to a V1 registry
+		pingV1 := func(scheme string) bool {
+			url := fmt.Sprintf(baseURLV1, scheme, c.registry)
+			resp, err := c.makeRequestToResolvedURL("GET", url, nil, nil, -1, true)
+			logrus.Debugf("Ping %s err %#v", url, err)
+			if err != nil {
+				return false
+			}
+			defer resp.Body.Close()
+			logrus.Debugf("Ping %s status %d", scheme+"://"+c.registry+"/v1/_ping", resp.StatusCode)
+			if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusUnauthorized {
+				return false
+			}
+			return true
+		}
+		isV1 := pingV1("https")
+		if !isV1 && c.ctx != nil && c.ctx.DockerInsecureSkipTLSVerify {
+			isV1 = pingV1("http")
+		}
+		if isV1 {
+			err = ErrV1NotSupported
+		}
+	}
 	return pr, err
 }
 
@@ -345,10 +461,6 @@ func getDefaultConfigDir(confPath string) string {
 	return filepath.Join(homedir.Get(), confPath)
 }
 
-type dockerAuthConfigObsolete struct {
-	Auth string `json:"auth"`
-}
-
 type dockerAuthConfig struct {
 	Auth string `json:"auth,omitempty"`
 }
@@ -371,3 +483,28 @@ func decodeDockerAuth(s string) (string, string, error) {
 	password := strings.Trim(parts[1], "\x00")
 	return user, password, nil
 }
+
+// convertToHostname converts a registry url which has http|https prepended
+// to just an hostname.
+// Copied from github.com/docker/docker/registry/auth.go
+func convertToHostname(url string) string {
+	stripped := url
+	if strings.HasPrefix(url, "http://") {
+		stripped = strings.TrimPrefix(url, "http://")
+	} else if strings.HasPrefix(url, "https://") {
+		stripped = strings.TrimPrefix(url, "https://")
+	}
+
+	nameParts := strings.SplitN(stripped, "/", 2)
+
+	return nameParts[0]
+}
+
+func normalizeRegistry(registry string) string {
+	normalized := convertToHostname(registry)
+	switch normalized {
+	case "registry-1.docker.io", "docker.io":
+		return "index.docker.io"
+	}
+	return normalized
+}

vendor/src/github.com/containers/image/docker/docker_image.go

@@ -24,7 +24,11 @@ func newImage(ctx *types.SystemContext, ref dockerReference) (types.Image, error
 	if err != nil {
 		return nil, err
 	}
-	return &Image{Image: image.FromSource(s), src: s}, nil
+	img, err := image.FromSource(s)
+	if err != nil {
+		return nil, err
+	}
+	return &Image{Image: img, src: s}, nil
 }
 
 // SourceRefFullName returns a fully expanded name for the repository this image is in.

vendor/src/github.com/containers/image/docker/docker_image_dest.go

@@ -2,8 +2,6 @@ package docker
 
 import (
 	"bytes"
-	"crypto/sha256"
-	"encoding/hex"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -11,18 +9,18 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
-	"strconv"
 
 	"github.com/Sirupsen/logrus"
 	"github.com/containers/image/manifest"
 	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
 )
 
 type dockerImageDestination struct {
 	ref dockerReference
 	c   *dockerClient
 	// State
-	manifestDigest string // or "" if not yet known.
+	manifestDigest digest.Digest // or "" if not yet known.
 }
 
 // newImageDestination creates a new ImageDestination for the specified image reference.
@@ -62,29 +60,52 @@ func (d *dockerImageDestination) SupportsSignatures() error {
 	return fmt.Errorf("Pushing signatures to a Docker Registry is not supported")
 }
 
-// PutBlob writes contents of stream and returns its computed digest and size.
-// A digest can be optionally provided if known, the specific image destination can decide to play with it or not.
-// The length of stream is expected to be expectedSize; if expectedSize == -1, it is not known.
+// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination.
+func (d *dockerImageDestination) ShouldCompressLayers() bool {
+	return true
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (d *dockerImageDestination) AcceptsForeignLayerURLs() bool {
+	return true
+}
+
+// sizeCounter is an io.Writer which only counts the total size of its input.
+type sizeCounter struct{ size int64 }
+
+func (c *sizeCounter) Write(p []byte) (n int, err error) {
+	c.size += int64(len(p))
+	return len(p), nil
+}
+
+// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+// inputInfo.Size is the expected length of stream, if known.
 // WARNING: The contents of stream are being verified on the fly.  Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
 // to any other readers for download using the supplied digest.
 // If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlob MUST 1) fail, and 2) delete any data stored so far.
-func (d *dockerImageDestination) PutBlob(stream io.Reader, digest string, expectedSize int64) (string, int64, error) {
-	if digest != "" {
-		checkURL := fmt.Sprintf(blobsURL, d.ref.ref.RemoteName(), digest)
+func (d *dockerImageDestination) PutBlob(stream io.Reader, inputInfo types.BlobInfo) (types.BlobInfo, error) {
+	if inputInfo.Digest.String() != "" {
+		checkURL := fmt.Sprintf(blobsURL, d.ref.ref.RemoteName(), inputInfo.Digest.String())
 
 		logrus.Debugf("Checking %s", checkURL)
 		res, err := d.c.makeRequest("HEAD", checkURL, nil, nil)
 		if err != nil {
-			return "", -1, err
+			return types.BlobInfo{}, err
 		}
 		defer res.Body.Close()
-		if res.StatusCode == http.StatusOK {
+		switch res.StatusCode {
+		case http.StatusOK:
 			logrus.Debugf("... already exists, not uploading")
-			blobLength, err := strconv.ParseInt(res.Header.Get("Content-Length"), 10, 64)
-			if err != nil {
-				return "", -1, err
-			}
-			return digest, blobLength, nil
+			return types.BlobInfo{Digest: inputInfo.Digest, Size: getBlobSize(res)}, nil
+		case http.StatusUnauthorized:
+			logrus.Debugf("... not authorized")
+			return types.BlobInfo{}, fmt.Errorf("not authorized to read from destination repository %s", d.ref.ref.RemoteName())
+		case http.StatusNotFound:
+			// noop
+		default:
+			return types.BlobInfo{}, fmt.Errorf("failed to read from destination repository %s: %v", d.ref.ref.RemoteName(), http.StatusText(res.StatusCode))
 		}
 		logrus.Debugf("... failed, status %d", res.StatusCode)
 	}
@@ -94,63 +115,99 @@ func (d *dockerImageDestination) PutBlob(stream io.Reader, digest string, expect
 	logrus.Debugf("Uploading %s", uploadURL)
 	res, err := d.c.makeRequest("POST", uploadURL, nil, nil)
 	if err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	defer res.Body.Close()
 	if res.StatusCode != http.StatusAccepted {
 		logrus.Debugf("Error initiating layer upload, response %#v", *res)
-		return "", -1, fmt.Errorf("Error initiating layer upload to %s, status %d", uploadURL, res.StatusCode)
+		return types.BlobInfo{}, fmt.Errorf("Error initiating layer upload to %s, status %d", uploadURL, res.StatusCode)
 	}
 	uploadLocation, err := res.Location()
 	if err != nil {
-		return "", -1, fmt.Errorf("Error determining upload URL: %s", err.Error())
+		return types.BlobInfo{}, fmt.Errorf("Error determining upload URL: %s", err.Error())
 	}
 
-	h := sha256.New()
-	tee := io.TeeReader(stream, h)
-	res, err = d.c.makeRequestToResolvedURL("PATCH", uploadLocation.String(), map[string][]string{"Content-Type": {"application/octet-stream"}}, tee, expectedSize)
+	digester := digest.Canonical.New()
+	sizeCounter := &sizeCounter{}
+	tee := io.TeeReader(stream, io.MultiWriter(digester.Hash(), sizeCounter))
+	res, err = d.c.makeRequestToResolvedURL("PATCH", uploadLocation.String(), map[string][]string{"Content-Type": {"application/octet-stream"}}, tee, inputInfo.Size, true)
 	if err != nil {
 		logrus.Debugf("Error uploading layer chunked, response %#v", *res)
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	defer res.Body.Close()
-	hash := h.Sum(nil)
-	computedDigest := "sha256:" + hex.EncodeToString(hash[:])
+	computedDigest := digester.Digest()
 
 	uploadLocation, err = res.Location()
 	if err != nil {
-		return "", -1, fmt.Errorf("Error determining upload URL: %s", err.Error())
+		return types.BlobInfo{}, fmt.Errorf("Error determining upload URL: %s", err.Error())
 	}
 
 	// FIXME: DELETE uploadLocation on failure
 
 	locationQuery := uploadLocation.Query()
-	// TODO: check digest == computedDigest https://github.com/containers/image/pull/70#discussion_r77646717
-	locationQuery.Set("digest", computedDigest)
+	// TODO: check inputInfo.Digest == computedDigest https://github.com/containers/image/pull/70#discussion_r77646717
+	locationQuery.Set("digest", computedDigest.String())
 	uploadLocation.RawQuery = locationQuery.Encode()
-	res, err = d.c.makeRequestToResolvedURL("PUT", uploadLocation.String(), map[string][]string{"Content-Type": {"application/octet-stream"}}, nil, -1)
+	res, err = d.c.makeRequestToResolvedURL("PUT", uploadLocation.String(), map[string][]string{"Content-Type": {"application/octet-stream"}}, nil, -1, true)
 	if err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	defer res.Body.Close()
 	if res.StatusCode != http.StatusCreated {
 		logrus.Debugf("Error uploading layer, response %#v", *res)
-		return "", -1, fmt.Errorf("Error uploading layer to %s, status %d", uploadLocation, res.StatusCode)
+		return types.BlobInfo{}, fmt.Errorf("Error uploading layer to %s, status %d", uploadLocation, res.StatusCode)
 	}
 
-	logrus.Debugf("Upload of layer %s complete", digest)
-	return computedDigest, res.Request.ContentLength, nil
+	logrus.Debugf("Upload of layer %s complete", computedDigest)
+	return types.BlobInfo{Digest: computedDigest, Size: sizeCounter.size}, nil
+}
+
+func (d *dockerImageDestination) HasBlob(info types.BlobInfo) (bool, int64, error) {
+	if info.Digest == "" {
+		return false, -1, fmt.Errorf(`"Can not check for a blob with unknown digest`)
+	}
+	checkURL := fmt.Sprintf(blobsURL, d.ref.ref.RemoteName(), info.Digest.String())
+
+	logrus.Debugf("Checking %s", checkURL)
+	res, err := d.c.makeRequest("HEAD", checkURL, nil, nil)
+	if err != nil {
+		return false, -1, err
+	}
+	defer res.Body.Close()
+	switch res.StatusCode {
+	case http.StatusOK:
+		logrus.Debugf("... already exists")
+		return true, getBlobSize(res), nil
+	case http.StatusUnauthorized:
+		logrus.Debugf("... not authorized")
+		return false, -1, fmt.Errorf("not authorized to read from destination repository %s", d.ref.ref.RemoteName())
+	case http.StatusNotFound:
+		logrus.Debugf("... not present")
+		return false, -1, types.ErrBlobNotFound
+	default:
+		logrus.Errorf("failed to read from destination repository %s: %v", d.ref.ref.RemoteName(), http.StatusText(res.StatusCode))
+	}
+	logrus.Debugf("... failed, status %d, ignoring", res.StatusCode)
+	return false, -1, types.ErrBlobNotFound
+}
+
+func (d *dockerImageDestination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
+	return info, nil
 }
 
 func (d *dockerImageDestination) PutManifest(m []byte) error {
-	// FIXME: This only allows upload by digest, not creating a tag.  See the
-	// corresponding comment in openshift.NewImageDestination.
 	digest, err := manifest.Digest(m)
 	if err != nil {
 		return err
 	}
 	d.manifestDigest = digest
-	url := fmt.Sprintf(manifestURL, d.ref.ref.RemoteName(), digest)
+
+	reference, err := d.ref.tagOrDigest()
+	if err != nil {
+		return err
+	}
+	url := fmt.Sprintf(manifestURL, d.ref.ref.RemoteName(), reference)
 
 	headers := map[string][]string{}
 	mimeType := manifest.GuessMIMEType(m)
@@ -185,8 +242,8 @@ func (d *dockerImageDestination) PutSignatures(signatures [][]byte) error {
 		return fmt.Errorf("Pushing signatures to a Docker Registry is not supported, and there is no applicable signature storage configured")
 	}
 
-	// FIXME: This assumption that signatures are stored after the manifest rather breaks the model.
-	if d.manifestDigest == "" {
+	if d.manifestDigest.String() == "" {
+		// This shouldn’t happen, ImageDestination users are required to call PutManifest before PutSignatures
 		return fmt.Errorf("Unknown manifest digest, can't add signatures")
 	}
 
@@ -237,6 +294,8 @@ func (d *dockerImageDestination) putOneSignature(url *url.URL, signature []byte)
 		}
 		return nil
 
+	case "http", "https":
+		return fmt.Errorf("Writing directly to a %s sigstore %s is not supported. Configure a sigstore-staging: location", url.Scheme, url.String())
 	default:
 		return fmt.Errorf("Unsupported scheme when writing signature to %s", url.String())
 	}
@@ -254,6 +313,8 @@ func (c *dockerClient) deleteOneSignature(url *url.URL) (missing bool, err error
 		}
 		return false, err
 
+	case "http", "https":
+		return false, fmt.Errorf("Writing directly to a %s sigstore %s is not supported. Configure a sigstore-staging: location", url.Scheme, url.String())
 	default:
 		return false, fmt.Errorf("Unsupported scheme when deleting signature from %s", url.String())
 	}

vendor/src/github.com/containers/image/docker/docker_image_src.go

@@ -13,17 +13,10 @@ import (
 	"github.com/Sirupsen/logrus"
 	"github.com/containers/image/manifest"
 	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+	"github.com/docker/distribution/registry/client"
 )
 
-type errFetchManifest struct {
-	statusCode int
-	body       []byte
-}
-
-func (e errFetchManifest) Error() string {
-	return fmt.Sprintf("error fetching manifest: status code: %d, body: %s", e.statusCode, string(e.body))
-}
-
 type dockerImageSource struct {
 	ref                        dockerReference
 	requestedManifestMIMETypes []string
@@ -75,6 +68,8 @@ func simplifyContentType(contentType string) string {
 	return mimeType
 }
 
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
 func (s *dockerImageSource) GetManifest() ([]byte, string, error) {
 	err := s.ensureManifestIsLoaded()
 	if err != nil {
@@ -83,6 +78,31 @@ func (s *dockerImageSource) GetManifest() ([]byte, string, error) {
 	return s.cachedManifest, s.cachedManifestMIMEType, nil
 }
 
+func (s *dockerImageSource) fetchManifest(tagOrDigest string) ([]byte, string, error) {
+	url := fmt.Sprintf(manifestURL, s.ref.ref.RemoteName(), tagOrDigest)
+	headers := make(map[string][]string)
+	headers["Accept"] = s.requestedManifestMIMETypes
+	res, err := s.c.makeRequest("GET", url, headers, nil)
+	if err != nil {
+		return nil, "", err
+	}
+	defer res.Body.Close()
+	if res.StatusCode != http.StatusOK {
+		return nil, "", client.HandleErrorResponse(res)
+	}
+	manblob, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, "", err
+	}
+	return manblob, simplifyContentType(res.Header.Get("Content-Type")), nil
+}
+
+// GetTargetManifest returns an image's manifest given a digest.
+// This is mainly used to retrieve a single image's manifest out of a manifest list.
+func (s *dockerImageSource) GetTargetManifest(digest digest.Digest) ([]byte, string, error) {
+	return s.fetchManifest(digest.String())
+}
+
 // ensureManifestIsLoaded sets s.cachedManifest and s.cachedManifestMIMEType
 //
 // ImageSource implementations are not required or expected to do any caching,
@@ -99,32 +119,53 @@ func (s *dockerImageSource) ensureManifestIsLoaded() error {
 	if err != nil {
 		return err
 	}
-	url := fmt.Sprintf(manifestURL, s.ref.ref.RemoteName(), reference)
-	// TODO(runcom) set manifest version header! schema1 for now - then schema2 etc etc and v1
-	// TODO(runcom) NO, switch on the resulter manifest like Docker is doing
-	headers := make(map[string][]string)
-	headers["Accept"] = s.requestedManifestMIMETypes
-	res, err := s.c.makeRequest("GET", url, headers, nil)
+
+	manblob, mt, err := s.fetchManifest(reference)
 	if err != nil {
 		return err
 	}
-	defer res.Body.Close()
-	manblob, err := ioutil.ReadAll(res.Body)
-	if err != nil {
-		return err
-	}
-	if res.StatusCode != http.StatusOK {
-		return errFetchManifest{res.StatusCode, manblob}
-	}
 	// We might validate manblob against the Docker-Content-Digest header here to protect against transport errors.
 	s.cachedManifest = manblob
-	s.cachedManifestMIMEType = simplifyContentType(res.Header.Get("Content-Type"))
+	s.cachedManifestMIMEType = mt
 	return nil
 }
 
+func (s *dockerImageSource) getExternalBlob(urls []string) (io.ReadCloser, int64, error) {
+	var (
+		resp *http.Response
+		err  error
+	)
+	for _, url := range urls {
+		resp, err = s.c.makeRequestToResolvedURL("GET", url, nil, nil, -1, false)
+		if err == nil {
+			if resp.StatusCode != http.StatusOK {
+				err = fmt.Errorf("error fetching external blob from %q: %d", url, resp.StatusCode)
+				logrus.Debug(err)
+				continue
+			}
+		}
+	}
+	if resp.Body != nil && err == nil {
+		return resp.Body, getBlobSize(resp), nil
+	}
+	return nil, 0, err
+}
+
+func getBlobSize(resp *http.Response) int64 {
+	size, err := strconv.ParseInt(resp.Header.Get("Content-Length"), 10, 64)
+	if err != nil {
+		size = -1
+	}
+	return size
+}
+
 // GetBlob returns a stream for the specified blob, and the blob’s size (or -1 if unknown).
-func (s *dockerImageSource) GetBlob(digest string) (io.ReadCloser, int64, error) {
-	url := fmt.Sprintf(blobsURL, s.ref.ref.RemoteName(), digest)
+func (s *dockerImageSource) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
+	if len(info.URLs) != 0 {
+		return s.getExternalBlob(info.URLs)
+	}
+
+	url := fmt.Sprintf(blobsURL, s.ref.ref.RemoteName(), info.Digest.String())
 	logrus.Debugf("Downloading %s", url)
 	res, err := s.c.makeRequest("GET", url, nil, nil)
 	if err != nil {
@@ -134,11 +175,7 @@ func (s *dockerImageSource) GetBlob(digest string) (io.ReadCloser, int64, error)
 		// print url also
 		return nil, 0, fmt.Errorf("Invalid status code returned when fetching blob %d", res.StatusCode)
 	}
-	size, err := strconv.ParseInt(res.Header.Get("Content-Length"), 10, 64)
-	if err != nil {
-		size = -1
-	}
-	return res.Body, size, nil
+	return res.Body, getBlobSize(res), nil
 }
 
 func (s *dockerImageSource) GetSignatures() ([][]byte, error) {
@@ -239,7 +276,7 @@ func deleteImage(ctx *types.SystemContext, ref dockerReference) error {
 	switch get.StatusCode {
 	case http.StatusOK:
 	case http.StatusNotFound:
-		return fmt.Errorf("Unable to delete %v. Image may not exist or is not stored with a v2 Schema in a v2 registry.", ref.ref)
+		return fmt.Errorf("Unable to delete %v. Image may not exist or is not stored with a v2 Schema in a v2 registry", ref.ref)
 	default:
 		return fmt.Errorf("Failed to delete %v: %s (%v)", ref.ref, manifestBody, get.Status)
 	}

vendor/src/github.com/containers/image/docker/docker_transport.go

@@ -5,8 +5,8 @@ import (
 	"strings"
 
 	"github.com/containers/image/docker/policyconfiguration"
+	"github.com/containers/image/docker/reference"
 	"github.com/containers/image/types"
-	"github.com/docker/docker/reference"
 )
 
 // Transport is an ImageTransport for Docker registry-hosted images.
@@ -115,8 +115,10 @@ func (ref dockerReference) PolicyConfigurationNamespaces() []string {
 	return policyconfiguration.DockerReferenceNamespaces(ref.ref)
 }
 
-// NewImage returns a types.Image for this reference.
+// NewImage returns a types.Image for this reference, possibly specialized for this ImageTransport.
 // The caller must call .Close() on the returned Image.
+// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage.
 func (ref dockerReference) NewImage(ctx *types.SystemContext) (types.Image, error) {
 	return newImage(ctx, ref)
 }

vendor/src/github.com/containers/image/docker/lookaside.go

@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/docker/distribution/digest"
 	"github.com/ghodss/yaml"
 
 	"github.com/Sirupsen/logrus"
@@ -188,11 +189,11 @@ func (ns registryNamespace) signatureTopLevel(write bool) string {
 
 // signatureStorageURL returns an URL usable for acessing signature index in base with known manifestDigest, or nil if not applicable.
 // Returns nil iff base == nil.
-func signatureStorageURL(base signatureStorageBase, manifestDigest string, index int) *url.URL {
+func signatureStorageURL(base signatureStorageBase, manifestDigest digest.Digest, index int) *url.URL {
 	if base == nil {
 		return nil
 	}
 	url := *base
-	url.Path = fmt.Sprintf("%s@%s/signature-%d", url.Path, manifestDigest, index+1)
+	url.Path = fmt.Sprintf("%s@%s/signature-%d", url.Path, manifestDigest.String(), index+1)
 	return &url
 }

vendor/src/github.com/containers/image/docker/policyconfiguration/naming.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/docker/docker/reference"
+	"github.com/containers/image/docker/reference"
 )
 
 // DockerReferenceIdentity returns a string representation of the reference, suitable for policy lookup,

vendor/src/github.com/containers/image/docker/reference/doc.go

@@ -0,0 +1,6 @@
+// Package reference is a fork of the upstream docker/docker/reference package.
+// The package is forked because we need consistency especially when storing and
+// checking signatures (RH patches break this consistency because they modify
+// docker/docker/reference as part of a patch carried in projectatomic/docker).
+// The version of this package is v1.12.1 from upstream, update as necessary.
+package reference

vendor/src/github.com/containers/image/docker/reference/reference.go

@@ -0,0 +1,220 @@
+package reference
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"strings"
+
+	"github.com/docker/distribution/digest"
+	distreference "github.com/docker/distribution/reference"
+)
+
+const (
+	// DefaultTag defines the default tag used when performing images related actions and no tag or digest is specified
+	DefaultTag = "latest"
+	// DefaultHostname is the default built-in hostname
+	DefaultHostname = "docker.io"
+	// LegacyDefaultHostname is automatically converted to DefaultHostname
+	LegacyDefaultHostname = "index.docker.io"
+	// DefaultRepoPrefix is the prefix used for default repositories in default host
+	DefaultRepoPrefix = "library/"
+)
+
+// Named is an object with a full name
+type Named interface {
+	// Name returns normalized repository name, like "ubuntu".
+	Name() string
+	// String returns full reference, like "ubuntu@sha256:abcdef..."
+	String() string
+	// FullName returns full repository name with hostname, like "docker.io/library/ubuntu"
+	FullName() string
+	// Hostname returns hostname for the reference, like "docker.io"
+	Hostname() string
+	// RemoteName returns the repository component of the full name, like "library/ubuntu"
+	RemoteName() string
+}
+
+// NamedTagged is an object including a name and tag.
+type NamedTagged interface {
+	Named
+	Tag() string
+}
+
+// Canonical reference is an object with a fully unique
+// name including a name with hostname and digest
+type Canonical interface {
+	Named
+	Digest() digest.Digest
+}
+
+// ParseNamed parses s and returns a syntactically valid reference implementing
+// the Named interface. The reference must have a name, otherwise an error is
+// returned.
+// If an error was encountered it is returned, along with a nil Reference.
+func ParseNamed(s string) (Named, error) {
+	named, err := distreference.ParseNamed(s)
+	if err != nil {
+		return nil, fmt.Errorf("Error parsing reference: %q is not a valid repository/tag", s)
+	}
+	r, err := WithName(named.Name())
+	if err != nil {
+		return nil, err
+	}
+	if canonical, isCanonical := named.(distreference.Canonical); isCanonical {
+		return WithDigest(r, canonical.Digest())
+	}
+	if tagged, isTagged := named.(distreference.NamedTagged); isTagged {
+		return WithTag(r, tagged.Tag())
+	}
+	return r, nil
+}
+
+// WithName returns a named object representing the given string. If the input
+// is invalid ErrReferenceInvalidFormat will be returned.
+func WithName(name string) (Named, error) {
+	name, err := normalize(name)
+	if err != nil {
+		return nil, err
+	}
+	if err := validateName(name); err != nil {
+		return nil, err
+	}
+	r, err := distreference.WithName(name)
+	if err != nil {
+		return nil, err
+	}
+	return &namedRef{r}, nil
+}
+
+// WithTag combines the name from "name" and the tag from "tag" to form a
+// reference incorporating both the name and the tag.
+func WithTag(name Named, tag string) (NamedTagged, error) {
+	r, err := distreference.WithTag(name, tag)
+	if err != nil {
+		return nil, err
+	}
+	return &taggedRef{namedRef{r}}, nil
+}
+
+// WithDigest combines the name from "name" and the digest from "digest" to form
+// a reference incorporating both the name and the digest.
+func WithDigest(name Named, digest digest.Digest) (Canonical, error) {
+	r, err := distreference.WithDigest(name, digest)
+	if err != nil {
+		return nil, err
+	}
+	return &canonicalRef{namedRef{r}}, nil
+}
+
+type namedRef struct {
+	distreference.Named
+}
+type taggedRef struct {
+	namedRef
+}
+type canonicalRef struct {
+	namedRef
+}
+
+func (r *namedRef) FullName() string {
+	hostname, remoteName := splitHostname(r.Name())
+	return hostname + "/" + remoteName
+}
+func (r *namedRef) Hostname() string {
+	hostname, _ := splitHostname(r.Name())
+	return hostname
+}
+func (r *namedRef) RemoteName() string {
+	_, remoteName := splitHostname(r.Name())
+	return remoteName
+}
+func (r *taggedRef) Tag() string {
+	return r.namedRef.Named.(distreference.NamedTagged).Tag()
+}
+func (r *canonicalRef) Digest() digest.Digest {
+	return r.namedRef.Named.(distreference.Canonical).Digest()
+}
+
+// WithDefaultTag adds a default tag to a reference if it only has a repo name.
+func WithDefaultTag(ref Named) Named {
+	if IsNameOnly(ref) {
+		ref, _ = WithTag(ref, DefaultTag)
+	}
+	return ref
+}
+
+// IsNameOnly returns true if reference only contains a repo name.
+func IsNameOnly(ref Named) bool {
+	if _, ok := ref.(NamedTagged); ok {
+		return false
+	}
+	if _, ok := ref.(Canonical); ok {
+		return false
+	}
+	return true
+}
+
+// ParseIDOrReference parses string for an image ID or a reference. ID can be
+// without a default prefix.
+func ParseIDOrReference(idOrRef string) (digest.Digest, Named, error) {
+	if err := validateID(idOrRef); err == nil {
+		idOrRef = "sha256:" + idOrRef
+	}
+	if dgst, err := digest.ParseDigest(idOrRef); err == nil {
+		return dgst, nil, nil
+	}
+	ref, err := ParseNamed(idOrRef)
+	return "", ref, err
+}
+
+// splitHostname splits a repository name to hostname and remotename string.
+// If no valid hostname is found, the default hostname is used. Repository name
+// needs to be already validated before.
+func splitHostname(name string) (hostname, remoteName string) {
+	i := strings.IndexRune(name, '/')
+	if i == -1 || (!strings.ContainsAny(name[:i], ".:") && name[:i] != "localhost") {
+		hostname, remoteName = DefaultHostname, name
+	} else {
+		hostname, remoteName = name[:i], name[i+1:]
+	}
+	if hostname == LegacyDefaultHostname {
+		hostname = DefaultHostname
+	}
+	if hostname == DefaultHostname && !strings.ContainsRune(remoteName, '/') {
+		remoteName = DefaultRepoPrefix + remoteName
+	}
+	return
+}
+
+// normalize returns a repository name in its normalized form, meaning it
+// will not contain default hostname nor library/ prefix for official images.
+func normalize(name string) (string, error) {
+	host, remoteName := splitHostname(name)
+	if strings.ToLower(remoteName) != remoteName {
+		return "", errors.New("invalid reference format: repository name must be lowercase")
+	}
+	if host == DefaultHostname {
+		if strings.HasPrefix(remoteName, DefaultRepoPrefix) {
+			return strings.TrimPrefix(remoteName, DefaultRepoPrefix), nil
+		}
+		return remoteName, nil
+	}
+	return name, nil
+}
+
+var validHex = regexp.MustCompile(`^([a-f0-9]{64})$`)
+
+func validateID(id string) error {
+	if ok := validHex.MatchString(id); !ok {
+		return fmt.Errorf("image ID %q is invalid", id)
+	}
+	return nil
+}
+
+func validateName(name string) error {
+	if err := validateID(name); err == nil {
+		return fmt.Errorf("Invalid repository name (%s), cannot specify 64-byte hexadecimal strings", name)
+	}
+	return nil
+}

vendor/src/github.com/containers/image/image/docker_list.go

@@ -0,0 +1,64 @@
+package image
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"runtime"
+
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+)
+
+type platformSpec struct {
+	Architecture string   `json:"architecture"`
+	OS           string   `json:"os"`
+	OSVersion    string   `json:"os.version,omitempty"`
+	OSFeatures   []string `json:"os.features,omitempty"`
+	Variant      string   `json:"variant,omitempty"`
+	Features     []string `json:"features,omitempty"`
+}
+
+// A manifestDescriptor references a platform-specific manifest.
+type manifestDescriptor struct {
+	descriptor
+	Platform platformSpec `json:"platform"`
+}
+
+type manifestList struct {
+	SchemaVersion int                  `json:"schemaVersion"`
+	MediaType     string               `json:"mediaType"`
+	Manifests     []manifestDescriptor `json:"manifests"`
+}
+
+func manifestSchema2FromManifestList(src types.ImageSource, manblob []byte) (genericManifest, error) {
+	list := manifestList{}
+	if err := json.Unmarshal(manblob, &list); err != nil {
+		return nil, err
+	}
+	var targetManifestDigest digest.Digest
+	for _, d := range list.Manifests {
+		if d.Platform.Architecture == runtime.GOARCH && d.Platform.OS == runtime.GOOS {
+			targetManifestDigest = d.Digest
+			break
+		}
+	}
+	if targetManifestDigest == "" {
+		return nil, errors.New("no supported platform found in manifest list")
+	}
+	manblob, mt, err := src.GetTargetManifest(targetManifestDigest)
+	if err != nil {
+		return nil, err
+	}
+
+	matches, err := manifest.MatchesDigest(manblob, targetManifestDigest)
+	if err != nil {
+		return nil, fmt.Errorf("Error computing manifest digest: %v", err)
+	}
+	if !matches {
+		return nil, fmt.Errorf("Manifest image does not match selected manifest digest %s", targetManifestDigest)
+	}
+
+	return manifestInstanceFromBlob(src, manblob, mt)
+}

vendor/src/github.com/containers/image/image/docker_schema1.go

@@ -0,0 +1,327 @@
+package image
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+)
+
+var (
+	validHex = regexp.MustCompile(`^([a-f0-9]{64})$`)
+)
+
+type fsLayersSchema1 struct {
+	BlobSum digest.Digest `json:"blobSum"`
+}
+
+type historySchema1 struct {
+	V1Compatibility string `json:"v1Compatibility"`
+}
+
+// historySchema1 is a string containing this.  It is similar to v1Image but not the same, in particular note the ThrowAway field.
+type v1Compatibility struct {
+	ID              string    `json:"id"`
+	Parent          string    `json:"parent,omitempty"`
+	Comment         string    `json:"comment,omitempty"`
+	Created         time.Time `json:"created"`
+	ContainerConfig struct {
+		Cmd []string
+	} `json:"container_config,omitempty"`
+	Author    string `json:"author,omitempty"`
+	ThrowAway bool   `json:"throwaway,omitempty"`
+}
+
+type manifestSchema1 struct {
+	Name          string            `json:"name"`
+	Tag           string            `json:"tag"`
+	Architecture  string            `json:"architecture"`
+	FSLayers      []fsLayersSchema1 `json:"fsLayers"`
+	History       []historySchema1  `json:"history"`
+	SchemaVersion int               `json:"schemaVersion"`
+}
+
+func manifestSchema1FromManifest(manifest []byte) (genericManifest, error) {
+	mschema1 := &manifestSchema1{}
+	if err := json.Unmarshal(manifest, mschema1); err != nil {
+		return nil, err
+	}
+	if mschema1.SchemaVersion != 1 {
+		return nil, fmt.Errorf("unsupported schema version %d", mschema1.SchemaVersion)
+	}
+	if len(mschema1.FSLayers) != len(mschema1.History) {
+		return nil, errors.New("length of history not equal to number of layers")
+	}
+	if len(mschema1.FSLayers) == 0 {
+		return nil, errors.New("no FSLayers in manifest")
+	}
+
+	if err := fixManifestLayers(mschema1); err != nil {
+		return nil, err
+	}
+	return mschema1, nil
+}
+
+// manifestSchema1FromComponents builds a new manifestSchema1 from the supplied data.
+func manifestSchema1FromComponents(ref reference.Named, fsLayers []fsLayersSchema1, history []historySchema1, architecture string) genericManifest {
+	var name, tag string
+	if ref != nil { // Well, what to do if it _is_ nil? Most consumers actually don't use these fields nowadays, so we might as well try not supplying them.
+		name = ref.RemoteName()
+		if tagged, ok := ref.(reference.NamedTagged); ok {
+			tag = tagged.Tag()
+		}
+	}
+	return &manifestSchema1{
+		Name:          name,
+		Tag:           tag,
+		Architecture:  architecture,
+		FSLayers:      fsLayers,
+		History:       history,
+		SchemaVersion: 1,
+	}
+}
+
+func (m *manifestSchema1) serialize() ([]byte, error) {
+	// docker/distribution requires a signature even if the incoming data uses the nominally unsigned DockerV2Schema1MediaType.
+	unsigned, err := json.Marshal(*m)
+	if err != nil {
+		return nil, err
+	}
+	return manifest.AddDummyV2S1Signature(unsigned)
+}
+
+func (m *manifestSchema1) manifestMIMEType() string {
+	return manifest.DockerV2Schema1SignedMediaType
+}
+
+// ConfigInfo returns a complete BlobInfo for the separate config object, or a BlobInfo{Digest:""} if there isn't a separate object.
+// Note that the config object may not exist in the underlying storage in the return value of UpdatedImage! Use ConfigBlob() below.
+func (m *manifestSchema1) ConfigInfo() types.BlobInfo {
+	return types.BlobInfo{}
+}
+
+// ConfigBlob returns the blob described by ConfigInfo, iff ConfigInfo().Digest != ""; nil otherwise.
+// The result is cached; it is OK to call this however often you need.
+func (m *manifestSchema1) ConfigBlob() ([]byte, error) {
+	return nil, nil
+}
+
+// LayerInfos returns a list of BlobInfos of layers referenced by this image, in order (the root layer first, and then successive layered layers).
+// The Digest field is guaranteed to be provided; Size may be -1.
+// WARNING: The list may contain duplicates, and they are semantically relevant.
+func (m *manifestSchema1) LayerInfos() []types.BlobInfo {
+	layers := make([]types.BlobInfo, len(m.FSLayers))
+	for i, layer := range m.FSLayers { // NOTE: This includes empty layers (where m.History.V1Compatibility->ThrowAway)
+		layers[(len(m.FSLayers)-1)-i] = types.BlobInfo{Digest: layer.BlobSum, Size: -1}
+	}
+	return layers
+}
+
+func (m *manifestSchema1) imageInspectInfo() (*types.ImageInspectInfo, error) {
+	v1 := &v1Image{}
+	if err := json.Unmarshal([]byte(m.History[0].V1Compatibility), v1); err != nil {
+		return nil, err
+	}
+	return &types.ImageInspectInfo{
+		Tag:           m.Tag,
+		DockerVersion: v1.DockerVersion,
+		Created:       v1.Created,
+		Labels:        v1.Config.Labels,
+		Architecture:  v1.Architecture,
+		Os:            v1.OS,
+	}, nil
+}
+
+// UpdatedImageNeedsLayerDiffIDs returns true iff UpdatedImage(options) needs InformationOnly.LayerDiffIDs.
+// This is a horribly specific interface, but computing InformationOnly.LayerDiffIDs can be very expensive to compute
+// (most importantly it forces us to download the full layers even if they are already present at the destination).
+func (m *manifestSchema1) UpdatedImageNeedsLayerDiffIDs(options types.ManifestUpdateOptions) bool {
+	return options.ManifestMIMEType == manifest.DockerV2Schema2MediaType
+}
+
+// UpdatedImage returns a types.Image modified according to options.
+// This does not change the state of the original Image object.
+func (m *manifestSchema1) UpdatedImage(options types.ManifestUpdateOptions) (types.Image, error) {
+	copy := *m
+	if options.LayerInfos != nil {
+		// Our LayerInfos includes empty layers (where m.History.V1Compatibility->ThrowAway), so expect them to be included here as well.
+		if len(copy.FSLayers) != len(options.LayerInfos) {
+			return nil, fmt.Errorf("Error preparing updated manifest: layer count changed from %d to %d", len(copy.FSLayers), len(options.LayerInfos))
+		}
+		for i, info := range options.LayerInfos {
+			// (docker push) sets up m.History.V1Compatibility->{Id,Parent} based on values of info.Digest,
+			// but (docker pull) ignores them in favor of computing DiffIDs from uncompressed data, except verifying the child->parent links and uniqueness.
+			// So, we don't bother recomputing the IDs in m.History.V1Compatibility.
+			copy.FSLayers[(len(options.LayerInfos)-1)-i].BlobSum = info.Digest
+		}
+	}
+
+	switch options.ManifestMIMEType {
+	case "": // No conversion, OK
+	case manifest.DockerV2Schema1MediaType, manifest.DockerV2Schema1SignedMediaType:
+	// We have 2 MIME types for schema 1, which are basically equivalent (even the un-"Signed" MIME type will be rejected if there isn’t a signature; so,
+	// handle conversions between them by doing nothing.
+	case manifest.DockerV2Schema2MediaType:
+		return copy.convertToManifestSchema2(options.InformationOnly.LayerInfos, options.InformationOnly.LayerDiffIDs)
+	default:
+		return nil, fmt.Errorf("Conversion of image manifest from %s to %s is not implemented", manifest.DockerV2Schema1SignedMediaType, options.ManifestMIMEType)
+	}
+
+	return memoryImageFromManifest(&copy), nil
+}
+
+// fixManifestLayers, after validating the supplied manifest
+// (to use correctly-formatted IDs, and to not have non-consecutive ID collisions in manifest.History),
+// modifies manifest to only have one entry for each layer ID in manifest.History (deleting the older duplicates,
+// both from manifest.History and manifest.FSLayers).
+// Note that even after this succeeds, manifest.FSLayers may contain duplicate entries
+// (for Dockerfile operations which change the configuration but not the filesystem).
+func fixManifestLayers(manifest *manifestSchema1) error {
+	type imageV1 struct {
+		ID     string
+		Parent string
+	}
+	// Per the specification, we can assume that len(manifest.FSLayers) == len(manifest.History)
+	imgs := make([]*imageV1, len(manifest.FSLayers))
+	for i := range manifest.FSLayers {
+		img := &imageV1{}
+
+		if err := json.Unmarshal([]byte(manifest.History[i].V1Compatibility), img); err != nil {
+			return err
+		}
+
+		imgs[i] = img
+		if err := validateV1ID(img.ID); err != nil {
+			return err
+		}
+	}
+	if imgs[len(imgs)-1].Parent != "" {
+		return errors.New("Invalid parent ID in the base layer of the image")
+	}
+	// check general duplicates to error instead of a deadlock
+	idmap := make(map[string]struct{})
+	var lastID string
+	for _, img := range imgs {
+		// skip IDs that appear after each other, we handle those later
+		if _, exists := idmap[img.ID]; img.ID != lastID && exists {
+			return fmt.Errorf("ID %+v appears multiple times in manifest", img.ID)
+		}
+		lastID = img.ID
+		idmap[lastID] = struct{}{}
+	}
+	// backwards loop so that we keep the remaining indexes after removing items
+	for i := len(imgs) - 2; i >= 0; i-- {
+		if imgs[i].ID == imgs[i+1].ID { // repeated ID. remove and continue
+			manifest.FSLayers = append(manifest.FSLayers[:i], manifest.FSLayers[i+1:]...)
+			manifest.History = append(manifest.History[:i], manifest.History[i+1:]...)
+		} else if imgs[i].Parent != imgs[i+1].ID {
+			return fmt.Errorf("Invalid parent ID. Expected %v, got %v", imgs[i+1].ID, imgs[i].Parent)
+		}
+	}
+	return nil
+}
+
+func validateV1ID(id string) error {
+	if ok := validHex.MatchString(id); !ok {
+		return fmt.Errorf("image ID %q is invalid", id)
+	}
+	return nil
+}
+
+// Based on github.com/docker/docker/distribution/pull_v2.go
+func (m *manifestSchema1) convertToManifestSchema2(uploadedLayerInfos []types.BlobInfo, layerDiffIDs []digest.Digest) (types.Image, error) {
+	if len(m.History) == 0 {
+		// What would this even mean?! Anyhow, the rest of the code depends on fsLayers[0] and history[0] existing.
+		return nil, fmt.Errorf("Cannot convert an image with 0 history entries to %s", manifest.DockerV2Schema2MediaType)
+	}
+	if len(m.History) != len(m.FSLayers) {
+		return nil, fmt.Errorf("Inconsistent schema 1 manifest: %d history entries, %d fsLayers entries", len(m.History), len(m.FSLayers))
+	}
+	if len(uploadedLayerInfos) != len(m.FSLayers) {
+		return nil, fmt.Errorf("Internal error: uploaded %d blobs, but schema1 manifest has %d fsLayers", len(uploadedLayerInfos), len(m.FSLayers))
+	}
+	if len(layerDiffIDs) != len(m.FSLayers) {
+		return nil, fmt.Errorf("Internal error: collected %d DiffID values, but schema1 manifest has %d fsLayers", len(layerDiffIDs), len(m.FSLayers))
+	}
+
+	rootFS := rootFS{
+		Type:      "layers",
+		DiffIDs:   []digest.Digest{},
+		BaseLayer: "",
+	}
+	var layers []descriptor
+	history := make([]imageHistory, len(m.History))
+	for v1Index := len(m.History) - 1; v1Index >= 0; v1Index-- {
+		v2Index := (len(m.History) - 1) - v1Index
+
+		var v1compat v1Compatibility
+		if err := json.Unmarshal([]byte(m.History[v1Index].V1Compatibility), &v1compat); err != nil {
+			return nil, fmt.Errorf("Error decoding history entry %d: %v", v1Index, err)
+		}
+		history[v2Index] = imageHistory{
+			Created:    v1compat.Created,
+			Author:     v1compat.Author,
+			CreatedBy:  strings.Join(v1compat.ContainerConfig.Cmd, " "),
+			Comment:    v1compat.Comment,
+			EmptyLayer: v1compat.ThrowAway,
+		}
+
+		if !v1compat.ThrowAway {
+			layers = append(layers, descriptor{
+				MediaType: "application/vnd.docker.image.rootfs.diff.tar.gzip",
+				Size:      uploadedLayerInfos[v2Index].Size,
+				Digest:    m.FSLayers[v1Index].BlobSum,
+			})
+			rootFS.DiffIDs = append(rootFS.DiffIDs, layerDiffIDs[v2Index])
+		}
+	}
+	configJSON, err := configJSONFromV1Config([]byte(m.History[0].V1Compatibility), rootFS, history)
+	if err != nil {
+		return nil, err
+	}
+	configDescriptor := descriptor{
+		MediaType: "application/vnd.docker.container.image.v1+json",
+		Size:      int64(len(configJSON)),
+		Digest:    digest.FromBytes(configJSON),
+	}
+
+	m2 := manifestSchema2FromComponents(configDescriptor, nil, configJSON, layers)
+	return memoryImageFromManifest(m2), nil
+}
+
+func configJSONFromV1Config(v1ConfigJSON []byte, rootFS rootFS, history []imageHistory) ([]byte, error) {
+	// github.com/docker/docker/image/v1/imagev1.go:MakeConfigFromV1Config unmarshals and re-marshals the input if docker_version is < 1.8.3 to remove blank fields;
+	// we don't do that here. FIXME? Should we? AFAICT it would only affect the digest value of the schema2 manifest, and we don't particularly need that to be
+	// a consistently reproducible value.
+
+	// Preserve everything we don't specifically know about.
+	// (This must be a *json.RawMessage, even though *[]byte is fairly redundant, because only *RawMessage implements json.Marshaler.)
+	rawContents := map[string]*json.RawMessage{}
+	if err := json.Unmarshal(v1ConfigJSON, &rawContents); err != nil { // We have already unmarshaled it before, using a more detailed schema?!
+		return nil, err
+	}
+
+	delete(rawContents, "id")
+	delete(rawContents, "parent")
+	delete(rawContents, "Size")
+	delete(rawContents, "parent_id")
+	delete(rawContents, "layer_id")
+	delete(rawContents, "throwaway")
+
+	updates := map[string]interface{}{"rootfs": rootFS, "history": history}
+	for field, value := range updates {
+		encoded, err := json.Marshal(value)
+		if err != nil {
+			return nil, err
+		}
+		rawContents[field] = (*json.RawMessage)(&encoded)
+	}
+	return json.Marshal(rawContents)
+}

vendor/src/github.com/containers/image/image/docker_schema2.go

@@ -0,0 +1,299 @@
+package image
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"strings"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+)
+
+// gzippedEmptyLayer is a gzip-compressed version of an empty tar file (1024 NULL bytes)
+// This comes from github.com/docker/distribution/manifest/schema1/config_builder.go; there is
+// a non-zero embedded timestamp; we could zero that, but that would just waste storage space
+// in registries, so let’s use the same values.
+var gzippedEmptyLayer = []byte{
+	31, 139, 8, 0, 0, 9, 110, 136, 0, 255, 98, 24, 5, 163, 96, 20, 140, 88,
+	0, 8, 0, 0, 255, 255, 46, 175, 181, 239, 0, 4, 0, 0,
+}
+
+// gzippedEmptyLayerDigest is a digest of gzippedEmptyLayer
+const gzippedEmptyLayerDigest = digest.Digest("sha256:a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4")
+
+type descriptor struct {
+	MediaType string        `json:"mediaType"`
+	Size      int64         `json:"size"`
+	Digest    digest.Digest `json:"digest"`
+	URLs      []string      `json:"urls,omitempty"`
+}
+
+type manifestSchema2 struct {
+	src               types.ImageSource // May be nil if configBlob is not nil
+	configBlob        []byte            // If set, corresponds to contents of ConfigDescriptor.
+	SchemaVersion     int               `json:"schemaVersion"`
+	MediaType         string            `json:"mediaType"`
+	ConfigDescriptor  descriptor        `json:"config"`
+	LayersDescriptors []descriptor      `json:"layers"`
+}
+
+func manifestSchema2FromManifest(src types.ImageSource, manifest []byte) (genericManifest, error) {
+	v2s2 := manifestSchema2{src: src}
+	if err := json.Unmarshal(manifest, &v2s2); err != nil {
+		return nil, err
+	}
+	return &v2s2, nil
+}
+
+// manifestSchema2FromComponents builds a new manifestSchema2 from the supplied data:
+func manifestSchema2FromComponents(config descriptor, src types.ImageSource, configBlob []byte, layers []descriptor) genericManifest {
+	return &manifestSchema2{
+		src:               src,
+		configBlob:        configBlob,
+		SchemaVersion:     2,
+		MediaType:         manifest.DockerV2Schema2MediaType,
+		ConfigDescriptor:  config,
+		LayersDescriptors: layers,
+	}
+}
+
+func (m *manifestSchema2) serialize() ([]byte, error) {
+	return json.Marshal(*m)
+}
+
+func (m *manifestSchema2) manifestMIMEType() string {
+	return m.MediaType
+}
+
+// ConfigInfo returns a complete BlobInfo for the separate config object, or a BlobInfo{Digest:""} if there isn't a separate object.
+// Note that the config object may not exist in the underlying storage in the return value of UpdatedImage! Use ConfigBlob() below.
+func (m *manifestSchema2) ConfigInfo() types.BlobInfo {
+	return types.BlobInfo{Digest: m.ConfigDescriptor.Digest, Size: m.ConfigDescriptor.Size}
+}
+
+// ConfigBlob returns the blob described by ConfigInfo, iff ConfigInfo().Digest != ""; nil otherwise.
+// The result is cached; it is OK to call this however often you need.
+func (m *manifestSchema2) ConfigBlob() ([]byte, error) {
+	if m.configBlob == nil {
+		if m.src == nil {
+			return nil, fmt.Errorf("Internal error: neither src nor configBlob set in manifestSchema2")
+		}
+		stream, _, err := m.src.GetBlob(types.BlobInfo{
+			Digest: m.ConfigDescriptor.Digest,
+			Size:   m.ConfigDescriptor.Size,
+			URLs:   m.ConfigDescriptor.URLs,
+		})
+		if err != nil {
+			return nil, err
+		}
+		defer stream.Close()
+		blob, err := ioutil.ReadAll(stream)
+		if err != nil {
+			return nil, err
+		}
+		computedDigest := digest.FromBytes(blob)
+		if computedDigest != m.ConfigDescriptor.Digest {
+			return nil, fmt.Errorf("Download config.json digest %s does not match expected %s", computedDigest, m.ConfigDescriptor.Digest)
+		}
+		m.configBlob = blob
+	}
+	return m.configBlob, nil
+}
+
+// LayerInfos returns a list of BlobInfos of layers referenced by this image, in order (the root layer first, and then successive layered layers).
+// The Digest field is guaranteed to be provided; Size may be -1.
+// WARNING: The list may contain duplicates, and they are semantically relevant.
+func (m *manifestSchema2) LayerInfos() []types.BlobInfo {
+	blobs := []types.BlobInfo{}
+	for _, layer := range m.LayersDescriptors {
+		blobs = append(blobs, types.BlobInfo{
+			Digest: layer.Digest,
+			Size:   layer.Size,
+			URLs:   layer.URLs,
+		})
+	}
+	return blobs
+}
+
+func (m *manifestSchema2) imageInspectInfo() (*types.ImageInspectInfo, error) {
+	config, err := m.ConfigBlob()
+	if err != nil {
+		return nil, err
+	}
+	v1 := &v1Image{}
+	if err := json.Unmarshal(config, v1); err != nil {
+		return nil, err
+	}
+	return &types.ImageInspectInfo{
+		DockerVersion: v1.DockerVersion,
+		Created:       v1.Created,
+		Labels:        v1.Config.Labels,
+		Architecture:  v1.Architecture,
+		Os:            v1.OS,
+	}, nil
+}
+
+// UpdatedImageNeedsLayerDiffIDs returns true iff UpdatedImage(options) needs InformationOnly.LayerDiffIDs.
+// This is a horribly specific interface, but computing InformationOnly.LayerDiffIDs can be very expensive to compute
+// (most importantly it forces us to download the full layers even if they are already present at the destination).
+func (m *manifestSchema2) UpdatedImageNeedsLayerDiffIDs(options types.ManifestUpdateOptions) bool {
+	return false
+}
+
+// UpdatedImage returns a types.Image modified according to options.
+// This does not change the state of the original Image object.
+func (m *manifestSchema2) UpdatedImage(options types.ManifestUpdateOptions) (types.Image, error) {
+	copy := *m // NOTE: This is not a deep copy, it still shares slices etc.
+	if options.LayerInfos != nil {
+		if len(copy.LayersDescriptors) != len(options.LayerInfos) {
+			return nil, fmt.Errorf("Error preparing updated manifest: layer count changed from %d to %d", len(copy.LayersDescriptors), len(options.LayerInfos))
+		}
+		copy.LayersDescriptors = make([]descriptor, len(options.LayerInfos))
+		for i, info := range options.LayerInfos {
+			copy.LayersDescriptors[i].Digest = info.Digest
+			copy.LayersDescriptors[i].Size = info.Size
+			copy.LayersDescriptors[i].URLs = info.URLs
+		}
+	}
+
+	switch options.ManifestMIMEType {
+	case "": // No conversion, OK
+	case manifest.DockerV2Schema1SignedMediaType, manifest.DockerV2Schema1MediaType:
+		return copy.convertToManifestSchema1(options.InformationOnly.Destination)
+	default:
+		return nil, fmt.Errorf("Conversion of image manifest from %s to %s is not implemented", manifest.DockerV2Schema2MediaType, options.ManifestMIMEType)
+	}
+
+	return memoryImageFromManifest(&copy), nil
+}
+
+// Based on docker/distribution/manifest/schema1/config_builder.go
+func (m *manifestSchema2) convertToManifestSchema1(dest types.ImageDestination) (types.Image, error) {
+	configBytes, err := m.ConfigBlob()
+	if err != nil {
+		return nil, err
+	}
+	imageConfig := &image{}
+	if err := json.Unmarshal(configBytes, imageConfig); err != nil {
+		return nil, err
+	}
+
+	// Build fsLayers and History, discarding all configs. We will patch the top-level config in later.
+	fsLayers := make([]fsLayersSchema1, len(imageConfig.History))
+	history := make([]historySchema1, len(imageConfig.History))
+	nonemptyLayerIndex := 0
+	var parentV1ID string // Set in the loop
+	v1ID := ""
+	haveGzippedEmptyLayer := false
+	if len(imageConfig.History) == 0 {
+		// What would this even mean?! Anyhow, the rest of the code depends on fsLayers[0] and history[0] existing.
+		return nil, fmt.Errorf("Cannot convert an image with 0 history entries to %s", manifest.DockerV2Schema1SignedMediaType)
+	}
+	for v2Index, historyEntry := range imageConfig.History {
+		parentV1ID = v1ID
+		v1Index := len(imageConfig.History) - 1 - v2Index
+
+		var blobDigest digest.Digest
+		if historyEntry.EmptyLayer {
+			if !haveGzippedEmptyLayer {
+				logrus.Debugf("Uploading empty layer during conversion to schema 1")
+				info, err := dest.PutBlob(bytes.NewReader(gzippedEmptyLayer), types.BlobInfo{Digest: gzippedEmptyLayerDigest, Size: int64(len(gzippedEmptyLayer))})
+				if err != nil {
+					return nil, fmt.Errorf("Error uploading empty layer: %v", err)
+				}
+				if info.Digest != gzippedEmptyLayerDigest {
+					return nil, fmt.Errorf("Internal error: Uploaded empty layer has digest %#v instead of %s", info.Digest, gzippedEmptyLayerDigest)
+				}
+				haveGzippedEmptyLayer = true
+			}
+			blobDigest = gzippedEmptyLayerDigest
+		} else {
+			if nonemptyLayerIndex >= len(m.LayersDescriptors) {
+				return nil, fmt.Errorf("Invalid image configuration, needs more than the %d distributed layers", len(m.LayersDescriptors))
+			}
+			blobDigest = m.LayersDescriptors[nonemptyLayerIndex].Digest
+			nonemptyLayerIndex++
+		}
+
+		// AFAICT pull ignores these ID values, at least nowadays, so we could use anything unique, including a simple counter. Use what Docker uses for cargo-cult consistency.
+		v, err := v1IDFromBlobDigestAndComponents(blobDigest, parentV1ID)
+		if err != nil {
+			return nil, err
+		}
+		v1ID = v
+
+		fakeImage := v1Compatibility{
+			ID:        v1ID,
+			Parent:    parentV1ID,
+			Comment:   historyEntry.Comment,
+			Created:   historyEntry.Created,
+			Author:    historyEntry.Author,
+			ThrowAway: historyEntry.EmptyLayer,
+		}
+		fakeImage.ContainerConfig.Cmd = []string{historyEntry.CreatedBy}
+		v1CompatibilityBytes, err := json.Marshal(&fakeImage)
+		if err != nil {
+			return nil, fmt.Errorf("Internal error: Error creating v1compatibility for %#v", fakeImage)
+		}
+
+		fsLayers[v1Index] = fsLayersSchema1{BlobSum: blobDigest}
+		history[v1Index] = historySchema1{V1Compatibility: string(v1CompatibilityBytes)}
+		// Note that parentV1ID of the top layer is preserved when exiting this loop
+	}
+
+	// Now patch in real configuration for the top layer (v1Index == 0)
+	v1ID, err = v1IDFromBlobDigestAndComponents(fsLayers[0].BlobSum, parentV1ID, string(configBytes)) // See above WRT v1ID value generation and cargo-cult consistency.
+	if err != nil {
+		return nil, err
+	}
+	v1Config, err := v1ConfigFromConfigJSON(configBytes, v1ID, parentV1ID, imageConfig.History[len(imageConfig.History)-1].EmptyLayer)
+	if err != nil {
+		return nil, err
+	}
+	history[0].V1Compatibility = string(v1Config)
+
+	m1 := manifestSchema1FromComponents(dest.Reference().DockerReference(), fsLayers, history, imageConfig.Architecture)
+	return memoryImageFromManifest(m1), nil
+}
+
+func v1IDFromBlobDigestAndComponents(blobDigest digest.Digest, others ...string) (string, error) {
+	if err := blobDigest.Validate(); err != nil {
+		return "", err
+	}
+	parts := append([]string{blobDigest.Hex()}, others...)
+	v1IDHash := sha256.Sum256([]byte(strings.Join(parts, " ")))
+	return hex.EncodeToString(v1IDHash[:]), nil
+}
+
+func v1ConfigFromConfigJSON(configJSON []byte, v1ID, parentV1ID string, throwaway bool) ([]byte, error) {
+	// Preserve everything we don't specifically know about.
+	// (This must be a *json.RawMessage, even though *[]byte is fairly redundant, because only *RawMessage implements json.Marshaler.)
+	rawContents := map[string]*json.RawMessage{}
+	if err := json.Unmarshal(configJSON, &rawContents); err != nil { // We have already unmarshaled it before, using a more detailed schema?!
+		return nil, err
+	}
+	delete(rawContents, "rootfs")
+	delete(rawContents, "history")
+
+	updates := map[string]interface{}{"id": v1ID}
+	if parentV1ID != "" {
+		updates["parent"] = parentV1ID
+	}
+	if throwaway {
+		updates["throwaway"] = throwaway
+	}
+	for field, value := range updates {
+		encoded, err := json.Marshal(value)
+		if err != nil {
+			return nil, err
+		}
+		rawContents[field] = (*json.RawMessage)(&encoded)
+	}
+	return json.Marshal(rawContents)
+}

vendor/src/github.com/containers/image/image/image.go

@@ -1,365 +0,0 @@
-// Package image consolidates knowledge about various container image formats
-// (as opposed to image storage mechanisms, which are handled by types.ImageSource)
-// and exposes all of them using an unified interface.
-package image
-
-import (
-	"encoding/json"
-	"errors"
-	"fmt"
-	"io/ioutil"
-	"regexp"
-	"time"
-
-	"github.com/containers/image/manifest"
-	"github.com/containers/image/types"
-)
-
-var (
-	validHex = regexp.MustCompile(`^([a-f0-9]{64})$`)
-)
-
-// genericImage is a general set of utilities for working with container images,
-// whatever is their underlying location (i.e. dockerImageSource-independent).
-// Note the existence of skopeo/docker.Image: some instances of a `types.Image`
-// may not be a `genericImage` directly. However, most users of `types.Image`
-// do not care, and those who care about `skopeo/docker.Image` know they do.
-type genericImage struct {
-	src types.ImageSource
-	// private cache for Manifest(); nil if not yet known.
-	cachedManifest []byte
-	// private cache for the manifest media type w/o having to guess it
-	// this may be the empty string in case the MIME Type wasn't guessed correctly
-	// this field is valid only if cachedManifest is not nil
-	cachedManifestMIMEType string
-	// private cache for Signatures(); nil if not yet known.
-	cachedSignatures [][]byte
-}
-
-// FromSource returns a types.Image implementation for source.
-// The caller must call .Close() on the returned Image.
-//
-// FromSource “takes ownership” of the input ImageSource and will call src.Close()
-// when the image is closed.  (This does not prevent callers from using both the
-// Image and ImageSource objects simultaneously, but it means that they only need to
-// the Image.)
-func FromSource(src types.ImageSource) types.Image {
-	return &genericImage{src: src}
-}
-
-// Reference returns the reference used to set up this source, _as specified by the user_
-// (not as the image itself, or its underlying storage, claims).  This can be used e.g. to determine which public keys are trusted for this image.
-func (i *genericImage) Reference() types.ImageReference {
-	return i.src.Reference()
-}
-
-// Close removes resources associated with an initialized Image, if any.
-func (i *genericImage) Close() {
-	i.src.Close()
-}
-
-// Manifest is like ImageSource.GetManifest, but the result is cached; it is OK to call this however often you need.
-// NOTE: It is essential for signature verification that Manifest returns the manifest from which BlobDigests is computed.
-func (i *genericImage) Manifest() ([]byte, string, error) {
-	if i.cachedManifest == nil {
-		m, mt, err := i.src.GetManifest()
-		if err != nil {
-			return nil, "", err
-		}
-		i.cachedManifest = m
-		if mt == "" || mt == "text/plain" {
-			// Crane registries can return "text/plain".
-			// This makes no real sense, but it happens
-			// because requests for manifests are
-			// redirected to a content distribution
-			// network which is configured that way.
-			mt = manifest.GuessMIMEType(i.cachedManifest)
-		}
-		i.cachedManifestMIMEType = mt
-	}
-	return i.cachedManifest, i.cachedManifestMIMEType, nil
-}
-
-// Signatures is like ImageSource.GetSignatures, but the result is cached; it is OK to call this however often you need.
-func (i *genericImage) Signatures() ([][]byte, error) {
-	if i.cachedSignatures == nil {
-		sigs, err := i.src.GetSignatures()
-		if err != nil {
-			return nil, err
-		}
-		i.cachedSignatures = sigs
-	}
-	return i.cachedSignatures, nil
-}
-
-func (i *genericImage) Inspect() (*types.ImageInspectInfo, error) {
-	// TODO(runcom): unused version param for now, default to docker v2-1
-	m, err := i.getParsedManifest()
-	if err != nil {
-		return nil, err
-	}
-	return m.ImageInspectInfo()
-}
-
-type config struct {
-	Labels map[string]string
-}
-
-type v1Image struct {
-	// Config is the configuration of the container received from the client
-	Config *config `json:"config,omitempty"`
-	// DockerVersion specifies version on which image is built
-	DockerVersion string `json:"docker_version,omitempty"`
-	// Created timestamp when image was created
-	Created time.Time `json:"created"`
-	// Architecture is the hardware that the image is build and runs on
-	Architecture string `json:"architecture,omitempty"`
-	// OS is the operating system used to build and run the image
-	OS string `json:"os,omitempty"`
-}
-
-// will support v1 one day...
-type genericManifest interface {
-	Config() ([]byte, error)
-	LayerDigests() []string
-	BlobDigests() []string
-	ImageInspectInfo() (*types.ImageInspectInfo, error)
-}
-
-type fsLayersSchema1 struct {
-	BlobSum string `json:"blobSum"`
-}
-
-// compile-time check that manifestSchema1 implements genericManifest
-var _ genericManifest = (*manifestSchema1)(nil)
-
-type manifestSchema1 struct {
-	Name     string
-	Tag      string
-	FSLayers []fsLayersSchema1 `json:"fsLayers"`
-	History  []struct {
-		V1Compatibility string `json:"v1Compatibility"`
-	} `json:"history"`
-	// TODO(runcom) verify the downloaded manifest
-	//Signature []byte `json:"signature"`
-}
-
-func (m *manifestSchema1) LayerDigests() []string {
-	layers := make([]string, len(m.FSLayers))
-	for i, layer := range m.FSLayers {
-		layers[i] = layer.BlobSum
-	}
-	return layers
-}
-
-func (m *manifestSchema1) BlobDigests() []string {
-	return m.LayerDigests()
-}
-
-func (m *manifestSchema1) Config() ([]byte, error) {
-	return []byte(m.History[0].V1Compatibility), nil
-}
-
-func (m *manifestSchema1) ImageInspectInfo() (*types.ImageInspectInfo, error) {
-	v1 := &v1Image{}
-	config, err := m.Config()
-	if err != nil {
-		return nil, err
-	}
-	if err := json.Unmarshal(config, v1); err != nil {
-		return nil, err
-	}
-	return &types.ImageInspectInfo{
-		Tag:           m.Tag,
-		DockerVersion: v1.DockerVersion,
-		Created:       v1.Created,
-		Labels:        v1.Config.Labels,
-		Architecture:  v1.Architecture,
-		Os:            v1.OS,
-		Layers:        m.LayerDigests(),
-	}, nil
-}
-
-// compile-time check that manifestSchema2 implements genericManifest
-var _ genericManifest = (*manifestSchema2)(nil)
-
-type manifestSchema2 struct {
-	src               types.ImageSource
-	ConfigDescriptor  descriptor   `json:"config"`
-	LayersDescriptors []descriptor `json:"layers"`
-}
-
-type descriptor struct {
-	MediaType string `json:"mediaType"`
-	Size      int64  `json:"size"`
-	Digest    string `json:"digest"`
-}
-
-func (m *manifestSchema2) LayerDigests() []string {
-	blobs := []string{}
-	for _, layer := range m.LayersDescriptors {
-		blobs = append(blobs, layer.Digest)
-	}
-	return blobs
-}
-
-func (m *manifestSchema2) BlobDigests() []string {
-	blobs := m.LayerDigests()
-	blobs = append(blobs, m.ConfigDescriptor.Digest)
-	return blobs
-}
-
-func (m *manifestSchema2) Config() ([]byte, error) {
-	rawConfig, _, err := m.src.GetBlob(m.ConfigDescriptor.Digest)
-	if err != nil {
-		return nil, err
-	}
-	config, err := ioutil.ReadAll(rawConfig)
-	rawConfig.Close()
-	return config, err
-}
-
-func (m *manifestSchema2) ImageInspectInfo() (*types.ImageInspectInfo, error) {
-	config, err := m.Config()
-	if err != nil {
-		return nil, err
-	}
-	v1 := &v1Image{}
-	if err := json.Unmarshal(config, v1); err != nil {
-		return nil, err
-	}
-	return &types.ImageInspectInfo{
-		DockerVersion: v1.DockerVersion,
-		Created:       v1.Created,
-		Labels:        v1.Config.Labels,
-		Architecture:  v1.Architecture,
-		Os:            v1.OS,
-		Layers:        m.LayerDigests(),
-	}, nil
-}
-
-// getParsedManifest parses the manifest into a data structure, cleans it up, and returns it.
-// NOTE: The manifest may have been modified in the process; DO NOT reserialize and store the return value
-// if you want to preserve the original manifest; use the blob returned by Manifest() directly.
-// NOTE: It is essential for signature verification that the object is computed from the same manifest which is returned by Manifest().
-func (i *genericImage) getParsedManifest() (genericManifest, error) {
-	manblob, mt, err := i.Manifest()
-	if err != nil {
-		return nil, err
-	}
-	switch mt {
-	// "application/json" is a valid v2s1 value per https://github.com/docker/distribution/blob/master/docs/spec/manifest-v2-1.md .
-	// This works for now, when nothing else seems to return "application/json"; if that were not true, the mapping/detection might
-	// need to happen within the ImageSource.
-	case manifest.DockerV2Schema1MediaType, manifest.DockerV2Schema1SignedMediaType, "application/json":
-		mschema1 := &manifestSchema1{}
-		if err := json.Unmarshal(manblob, mschema1); err != nil {
-			return nil, err
-		}
-		if err := fixManifestLayers(mschema1); err != nil {
-			return nil, err
-		}
-		// TODO(runcom): verify manifest schema 1, 2 etc
-		//if len(m.FSLayers) != len(m.History) {
-		//return nil, fmt.Errorf("length of history not equal to number of layers for %q", ref.String())
-		//}
-		//if len(m.FSLayers) == 0 {
-		//return nil, fmt.Errorf("no FSLayers in manifest for %q", ref.String())
-		//}
-		return mschema1, nil
-	case manifest.DockerV2Schema2MediaType:
-		v2s2 := manifestSchema2{src: i.src}
-		if err := json.Unmarshal(manblob, &v2s2); err != nil {
-			return nil, err
-		}
-		return &v2s2, nil
-	case "":
-		return nil, errors.New("could not guess manifest media type")
-	default:
-		return nil, fmt.Errorf("unsupported manifest media type %s", mt)
-	}
-}
-
-// uniqueBlobDigests returns a list of blob digests referenced from a manifest.
-// The list will not contain duplicates; it is not intended to correspond to the "history" or "parent chain" of a Docker image.
-func uniqueBlobDigests(m genericManifest) []string {
-	var res []string
-	seen := make(map[string]struct{})
-	for _, digest := range m.BlobDigests() {
-		if _, ok := seen[digest]; ok {
-			continue
-		}
-		seen[digest] = struct{}{}
-		res = append(res, digest)
-	}
-	return res
-}
-
-// BlobDigests returns a list of blob digests referenced by this image.
-// The list will not contain duplicates; it is not intended to correspond to the "history" or "parent chain" of a Docker image.
-// NOTE: It is essential for signature verification that BlobDigests is computed from the same manifest which is returned by Manifest().
-func (i *genericImage) BlobDigests() ([]string, error) {
-	m, err := i.getParsedManifest()
-	if err != nil {
-		return nil, err
-	}
-	return uniqueBlobDigests(m), nil
-}
-
-// fixManifestLayers, after validating the supplied manifest
-// (to use correctly-formatted IDs, and to not have non-consecutive ID collisions in manifest.History),
-// modifies manifest to only have one entry for each layer ID in manifest.History (deleting the older duplicates,
-// both from manifest.History and manifest.FSLayers).
-// Note that even after this succeeds, manifest.FSLayers may contain duplicate entries
-// (for Dockerfile operations which change the configuration but not the filesystem).
-func fixManifestLayers(manifest *manifestSchema1) error {
-	type imageV1 struct {
-		ID     string
-		Parent string
-	}
-	// Per the specification, we can assume that len(manifest.FSLayers) == len(manifest.History)
-	imgs := make([]*imageV1, len(manifest.FSLayers))
-	for i := range manifest.FSLayers {
-		img := &imageV1{}
-
-		if err := json.Unmarshal([]byte(manifest.History[i].V1Compatibility), img); err != nil {
-			return err
-		}
-
-		imgs[i] = img
-		if err := validateV1ID(img.ID); err != nil {
-			return err
-		}
-	}
-	if imgs[len(imgs)-1].Parent != "" {
-		return errors.New("Invalid parent ID in the base layer of the image.")
-	}
-	// check general duplicates to error instead of a deadlock
-	idmap := make(map[string]struct{})
-	var lastID string
-	for _, img := range imgs {
-		// skip IDs that appear after each other, we handle those later
-		if _, exists := idmap[img.ID]; img.ID != lastID && exists {
-			return fmt.Errorf("ID %+v appears multiple times in manifest", img.ID)
-		}
-		lastID = img.ID
-		idmap[lastID] = struct{}{}
-	}
-	// backwards loop so that we keep the remaining indexes after removing items
-	for i := len(imgs) - 2; i >= 0; i-- {
-		if imgs[i].ID == imgs[i+1].ID { // repeated ID. remove and continue
-			manifest.FSLayers = append(manifest.FSLayers[:i], manifest.FSLayers[i+1:]...)
-			manifest.History = append(manifest.History[:i], manifest.History[i+1:]...)
-		} else if imgs[i].Parent != imgs[i+1].ID {
-			return fmt.Errorf("Invalid parent ID. Expected %v, got %v.", imgs[i+1].ID, imgs[i].Parent)
-		}
-	}
-	return nil
-}
-
-func validateV1ID(id string) error {
-	if ok := validHex.MatchString(id); !ok {
-		return fmt.Errorf("image ID %q is invalid", id)
-	}
-	return nil
-}

vendor/src/github.com/containers/image/image/manifest.go

@@ -0,0 +1,121 @@
+package image
+
+import (
+	"time"
+
+	"github.com/docker/distribution/digest"
+	"github.com/docker/engine-api/types/strslice"
+
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+type config struct {
+	Cmd    strslice.StrSlice
+	Labels map[string]string
+}
+
+type v1Image struct {
+	ID              string    `json:"id,omitempty"`
+	Parent          string    `json:"parent,omitempty"`
+	Comment         string    `json:"comment,omitempty"`
+	Created         time.Time `json:"created"`
+	ContainerConfig *config   `json:"container_config,omitempty"`
+	DockerVersion   string    `json:"docker_version,omitempty"`
+	Author          string    `json:"author,omitempty"`
+	// Config is the configuration of the container received from the client
+	Config *config `json:"config,omitempty"`
+	// Architecture is the hardware that the image is build and runs on
+	Architecture string `json:"architecture,omitempty"`
+	// OS is the operating system used to build and run the image
+	OS string `json:"os,omitempty"`
+}
+
+type image struct {
+	v1Image
+	History []imageHistory `json:"history,omitempty"`
+	RootFS  *rootFS        `json:"rootfs,omitempty"`
+}
+
+type imageHistory struct {
+	Created    time.Time `json:"created"`
+	Author     string    `json:"author,omitempty"`
+	CreatedBy  string    `json:"created_by,omitempty"`
+	Comment    string    `json:"comment,omitempty"`
+	EmptyLayer bool      `json:"empty_layer,omitempty"`
+}
+
+type rootFS struct {
+	Type      string          `json:"type"`
+	DiffIDs   []digest.Digest `json:"diff_ids,omitempty"`
+	BaseLayer string          `json:"base_layer,omitempty"`
+}
+
+// genericManifest is an interface for parsing, modifying image manifests and related data.
+// Note that the public methods are intended to be a subset of types.Image
+// so that embedding a genericManifest into structs works.
+// will support v1 one day...
+type genericManifest interface {
+	serialize() ([]byte, error)
+	manifestMIMEType() string
+	// ConfigInfo returns a complete BlobInfo for the separate config object, or a BlobInfo{Digest:""} if there isn't a separate object.
+	// Note that the config object may not exist in the underlying storage in the return value of UpdatedImage! Use ConfigBlob() below.
+	ConfigInfo() types.BlobInfo
+	// ConfigBlob returns the blob described by ConfigInfo, iff ConfigInfo().Digest != ""; nil otherwise.
+	// The result is cached; it is OK to call this however often you need.
+	ConfigBlob() ([]byte, error)
+	// LayerInfos returns a list of BlobInfos of layers referenced by this image, in order (the root layer first, and then successive layered layers).
+	// The Digest field is guaranteed to be provided; Size may be -1.
+	// WARNING: The list may contain duplicates, and they are semantically relevant.
+	LayerInfos() []types.BlobInfo
+	imageInspectInfo() (*types.ImageInspectInfo, error) // To be called by inspectManifest
+	// UpdatedImageNeedsLayerDiffIDs returns true iff UpdatedImage(options) needs InformationOnly.LayerDiffIDs.
+	// This is a horribly specific interface, but computing InformationOnly.LayerDiffIDs can be very expensive to compute
+	// (most importantly it forces us to download the full layers even if they are already present at the destination).
+	UpdatedImageNeedsLayerDiffIDs(options types.ManifestUpdateOptions) bool
+	// UpdatedImage returns a types.Image modified according to options.
+	// This does not change the state of the original Image object.
+	UpdatedImage(options types.ManifestUpdateOptions) (types.Image, error)
+}
+
+func manifestInstanceFromBlob(src types.ImageSource, manblob []byte, mt string) (genericManifest, error) {
+	switch mt {
+	// "application/json" is a valid v2s1 value per https://github.com/docker/distribution/blob/master/docs/spec/manifest-v2-1.md .
+	// This works for now, when nothing else seems to return "application/json"; if that were not true, the mapping/detection might
+	// need to happen within the ImageSource.
+	case manifest.DockerV2Schema1MediaType, manifest.DockerV2Schema1SignedMediaType, "application/json":
+		return manifestSchema1FromManifest(manblob)
+	case imgspecv1.MediaTypeImageManifest:
+		return manifestOCI1FromManifest(src, manblob)
+	case manifest.DockerV2Schema2MediaType:
+		return manifestSchema2FromManifest(src, manblob)
+	case manifest.DockerV2ListMediaType:
+		return manifestSchema2FromManifestList(src, manblob)
+	default:
+		// If it's not a recognized manifest media type, or we have failed determining the type, we'll try one last time
+		// to deserialize using v2s1 as per https://github.com/docker/distribution/blob/master/manifests.go#L108
+		// and https://github.com/docker/distribution/blob/master/manifest/schema1/manifest.go#L50
+		//
+		// Crane registries can also return "text/plain", or pretty much anything else depending on a file extension “recognized” in the tag.
+		// This makes no real sense, but it happens
+		// because requests for manifests are
+		// redirected to a content distribution
+		// network which is configured that way. See https://bugzilla.redhat.com/show_bug.cgi?id=1389442
+		return manifestSchema1FromManifest(manblob)
+	}
+}
+
+// inspectManifest is an implementation of types.Image.Inspect
+func inspectManifest(m genericManifest) (*types.ImageInspectInfo, error) {
+	info, err := m.imageInspectInfo()
+	if err != nil {
+		return nil, err
+	}
+	layers := m.LayerInfos()
+	info.Layers = make([]string, len(layers))
+	for i, layer := range layers {
+		info.Layers[i] = layer.Digest.String()
+	}
+	return info, nil
+}

vendor/src/github.com/containers/image/image/memory.go

@@ -0,0 +1,74 @@
+package image
+
+import (
+	"errors"
+
+	"github.com/containers/image/types"
+)
+
+// memoryImage is a mostly-implementation of types.Image assembled from data
+// created in memory, used primarily as a return value of types.Image.UpdatedImage
+// as a way to carry various structured information in a type-safe and easy-to-use way.
+// Note that this _only_ carries the immediate metadata; it is _not_ a stand-alone
+// collection of all related information, e.g. there is no way to get layer blobs
+// from a memoryImage.
+type memoryImage struct {
+	genericManifest
+	serializedManifest []byte // A private cache for Manifest()
+}
+
+func memoryImageFromManifest(m genericManifest) types.Image {
+	return &memoryImage{
+		genericManifest:    m,
+		serializedManifest: nil,
+	}
+}
+
+// Reference returns the reference used to set up this source, _as specified by the user_
+// (not as the image itself, or its underlying storage, claims).  This can be used e.g. to determine which public keys are trusted for this image.
+func (i *memoryImage) Reference() types.ImageReference {
+	// It would really be inappropriate to return the ImageReference of the image this was based on.
+	return nil
+}
+
+// Close removes resources associated with an initialized UnparsedImage, if any.
+func (i *memoryImage) Close() {
+}
+
+// Size returns the size of the image as stored, if known, or -1 if not.
+func (i *memoryImage) Size() (int64, error) {
+	s, err := i.serialize()
+	if err != nil {
+		return -1, err
+	}
+	return int64(len(s)), nil
+}
+
+// Manifest is like ImageSource.GetManifest, but the result is cached; it is OK to call this however often you need.
+func (i *memoryImage) Manifest() ([]byte, string, error) {
+	if i.serializedManifest == nil {
+		m, err := i.genericManifest.serialize()
+		if err != nil {
+			return nil, "", err
+		}
+		i.serializedManifest = m
+	}
+	return i.serializedManifest, i.genericManifest.manifestMIMEType(), nil
+}
+
+// Signatures is like ImageSource.GetSignatures, but the result is cached; it is OK to call this however often you need.
+func (i *memoryImage) Signatures() ([][]byte, error) {
+	// Modifying an image invalidates signatures; a caller asking the updated image for signatures
+	// is probably confused.
+	return nil, errors.New("Internal error: Image.Signatures() is not supported for images modified in memory")
+}
+
+// Inspect returns various information for (skopeo inspect) parsed from the manifest and configuration.
+func (i *memoryImage) Inspect() (*types.ImageInspectInfo, error) {
+	return inspectManifest(i.genericManifest)
+}
+
+// IsMultiImage returns true if the image's manifest is a list of images, false otherwise.
+func (i *memoryImage) IsMultiImage() bool {
+	return false
+}

vendor/src/github.com/containers/image/image/oci.go

@@ -0,0 +1,167 @@
+package image
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+type manifestOCI1 struct {
+	src               types.ImageSource // May be nil if configBlob is not nil
+	configBlob        []byte            // If set, corresponds to contents of ConfigDescriptor.
+	SchemaVersion     int               `json:"schemaVersion"`
+	MediaType         string            `json:"mediaType"`
+	ConfigDescriptor  descriptor        `json:"config"`
+	LayersDescriptors []descriptor      `json:"layers"`
+}
+
+func manifestOCI1FromManifest(src types.ImageSource, manifest []byte) (genericManifest, error) {
+	oci := manifestOCI1{src: src}
+	if err := json.Unmarshal(manifest, &oci); err != nil {
+		return nil, err
+	}
+	return &oci, nil
+}
+
+// manifestOCI1FromComponents builds a new manifestOCI1 from the supplied data:
+func manifestOCI1FromComponents(config descriptor, configBlob []byte, layers []descriptor) genericManifest {
+	return &manifestOCI1{
+		src:               nil,
+		configBlob:        configBlob,
+		SchemaVersion:     2,
+		MediaType:         imgspecv1.MediaTypeImageManifest,
+		ConfigDescriptor:  config,
+		LayersDescriptors: layers,
+	}
+}
+
+func (m *manifestOCI1) serialize() ([]byte, error) {
+	return json.Marshal(*m)
+}
+
+func (m *manifestOCI1) manifestMIMEType() string {
+	return m.MediaType
+}
+
+// ConfigInfo returns a complete BlobInfo for the separate config object, or a BlobInfo{Digest:""} if there isn't a separate object.
+// Note that the config object may not exist in the underlying storage in the return value of UpdatedImage! Use ConfigBlob() below.
+func (m *manifestOCI1) ConfigInfo() types.BlobInfo {
+	return types.BlobInfo{Digest: m.ConfigDescriptor.Digest, Size: m.ConfigDescriptor.Size}
+}
+
+// ConfigBlob returns the blob described by ConfigInfo, iff ConfigInfo().Digest != ""; nil otherwise.
+// The result is cached; it is OK to call this however often you need.
+func (m *manifestOCI1) ConfigBlob() ([]byte, error) {
+	if m.configBlob == nil {
+		if m.src == nil {
+			return nil, fmt.Errorf("Internal error: neither src nor configBlob set in manifestOCI1")
+		}
+		stream, _, err := m.src.GetBlob(types.BlobInfo{
+			Digest: m.ConfigDescriptor.Digest,
+			Size:   m.ConfigDescriptor.Size,
+			URLs:   m.ConfigDescriptor.URLs,
+		})
+		if err != nil {
+			return nil, err
+		}
+		defer stream.Close()
+		blob, err := ioutil.ReadAll(stream)
+		if err != nil {
+			return nil, err
+		}
+		computedDigest := digest.FromBytes(blob)
+		if computedDigest != m.ConfigDescriptor.Digest {
+			return nil, fmt.Errorf("Download config.json digest %s does not match expected %s", computedDigest, m.ConfigDescriptor.Digest)
+		}
+		m.configBlob = blob
+	}
+	return m.configBlob, nil
+}
+
+// LayerInfos returns a list of BlobInfos of layers referenced by this image, in order (the root layer first, and then successive layered layers).
+// The Digest field is guaranteed to be provided; Size may be -1.
+// WARNING: The list may contain duplicates, and they are semantically relevant.
+func (m *manifestOCI1) LayerInfos() []types.BlobInfo {
+	blobs := []types.BlobInfo{}
+	for _, layer := range m.LayersDescriptors {
+		blobs = append(blobs, types.BlobInfo{Digest: layer.Digest, Size: layer.Size})
+	}
+	return blobs
+}
+
+func (m *manifestOCI1) imageInspectInfo() (*types.ImageInspectInfo, error) {
+	config, err := m.ConfigBlob()
+	if err != nil {
+		return nil, err
+	}
+	v1 := &v1Image{}
+	if err := json.Unmarshal(config, v1); err != nil {
+		return nil, err
+	}
+	return &types.ImageInspectInfo{
+		DockerVersion: v1.DockerVersion,
+		Created:       v1.Created,
+		Labels:        v1.Config.Labels,
+		Architecture:  v1.Architecture,
+		Os:            v1.OS,
+	}, nil
+}
+
+// UpdatedImageNeedsLayerDiffIDs returns true iff UpdatedImage(options) needs InformationOnly.LayerDiffIDs.
+// This is a horribly specific interface, but computing InformationOnly.LayerDiffIDs can be very expensive to compute
+// (most importantly it forces us to download the full layers even if they are already present at the destination).
+func (m *manifestOCI1) UpdatedImageNeedsLayerDiffIDs(options types.ManifestUpdateOptions) bool {
+	return false
+}
+
+// UpdatedImage returns a types.Image modified according to options.
+// This does not change the state of the original Image object.
+func (m *manifestOCI1) UpdatedImage(options types.ManifestUpdateOptions) (types.Image, error) {
+	copy := *m // NOTE: This is not a deep copy, it still shares slices etc.
+	if options.LayerInfos != nil {
+		if len(copy.LayersDescriptors) != len(options.LayerInfos) {
+			return nil, fmt.Errorf("Error preparing updated manifest: layer count changed from %d to %d", len(copy.LayersDescriptors), len(options.LayerInfos))
+		}
+		copy.LayersDescriptors = make([]descriptor, len(options.LayerInfos))
+		for i, info := range options.LayerInfos {
+			copy.LayersDescriptors[i].Digest = info.Digest
+			copy.LayersDescriptors[i].Size = info.Size
+		}
+	}
+
+	switch options.ManifestMIMEType {
+	case "": // No conversion, OK
+	case manifest.DockerV2Schema2MediaType:
+		return copy.convertToManifestSchema2()
+	default:
+		return nil, fmt.Errorf("Conversion of image manifest from %s to %s is not implemented", imgspecv1.MediaTypeImageManifest, options.ManifestMIMEType)
+	}
+
+	return memoryImageFromManifest(&copy), nil
+}
+
+func (m *manifestOCI1) convertToManifestSchema2() (types.Image, error) {
+	// Create a copy of the descriptor.
+	config := m.ConfigDescriptor
+
+	// The only difference between OCI and DockerSchema2 is the mediatypes. The
+	// media type of the manifest is handled by manifestSchema2FromComponents.
+	config.MediaType = manifest.DockerV2Schema2ConfigMediaType
+
+	layers := make([]descriptor, len(m.LayersDescriptors))
+	for idx := range layers {
+		layers[idx] = m.LayersDescriptors[idx]
+		layers[idx].MediaType = manifest.DockerV2Schema2LayerMediaType
+	}
+
+	// Rather than copying the ConfigBlob now, we just pass m.src to the
+	// translated manifest, since the only difference is the mediatype of
+	// descriptors there is no change to any blob stored in m.src.
+	m1 := manifestSchema2FromComponents(config, m.src, nil, layers)
+	return memoryImageFromManifest(m1), nil
+}

vendor/src/github.com/containers/image/image/sourced.go

@@ -0,0 +1,90 @@
+// Package image consolidates knowledge about various container image formats
+// (as opposed to image storage mechanisms, which are handled by types.ImageSource)
+// and exposes all of them using an unified interface.
+package image
+
+import (
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+)
+
+// FromSource returns a types.Image implementation for source.
+// The caller must call .Close() on the returned Image.
+//
+// FromSource “takes ownership” of the input ImageSource and will call src.Close()
+// when the image is closed.  (This does not prevent callers from using both the
+// Image and ImageSource objects simultaneously, but it means that they only need to
+// the Image.)
+//
+// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage instead of calling this function.
+func FromSource(src types.ImageSource) (types.Image, error) {
+	return FromUnparsedImage(UnparsedFromSource(src))
+}
+
+// sourcedImage is a general set of utilities for working with container images,
+// whatever is their underlying location (i.e. dockerImageSource-independent).
+// Note the existence of skopeo/docker.Image: some instances of a `types.Image`
+// may not be a `sourcedImage` directly. However, most users of `types.Image`
+// do not care, and those who care about `skopeo/docker.Image` know they do.
+type sourcedImage struct {
+	*UnparsedImage
+	manifestBlob     []byte
+	manifestMIMEType string
+	// genericManifest contains data corresponding to manifestBlob.
+	// NOTE: The manifest may have been modified in the process; DO NOT reserialize and store genericManifest
+	// if you want to preserve the original manifest; use manifestBlob directly.
+	genericManifest
+}
+
+// FromUnparsedImage returns a types.Image implementation for unparsed.
+// The caller must call .Close() on the returned Image.
+//
+// FromSource “takes ownership” of the input UnparsedImage and will call uparsed.Close()
+// when the image is closed.  (This does not prevent callers from using both the
+// UnparsedImage and ImageSource objects simultaneously, but it means that they only need to
+// keep a reference to the Image.)
+func FromUnparsedImage(unparsed *UnparsedImage) (types.Image, error) {
+	// Note that the input parameter above is specifically *image.UnparsedImage, not types.UnparsedImage:
+	// we want to be able to use unparsed.src.  We could make that an explicit interface, but, well,
+	// this is the only UnparsedImage implementation around, anyway.
+
+	// Also, we do not explicitly implement types.Image.Close; we let the implementation fall through to
+	// unparsed.Close.
+
+	// NOTE: It is essential for signature verification that all parsing done in this object happens on the same manifest which is returned by unparsed.Manifest().
+	manifestBlob, manifestMIMEType, err := unparsed.Manifest()
+	if err != nil {
+		return nil, err
+	}
+
+	parsedManifest, err := manifestInstanceFromBlob(unparsed.src, manifestBlob, manifestMIMEType)
+	if err != nil {
+		return nil, err
+	}
+
+	return &sourcedImage{
+		UnparsedImage:    unparsed,
+		manifestBlob:     manifestBlob,
+		manifestMIMEType: manifestMIMEType,
+		genericManifest:  parsedManifest,
+	}, nil
+}
+
+// Size returns the size of the image as stored, if it's known, or -1 if it isn't.
+func (i *sourcedImage) Size() (int64, error) {
+	return -1, nil
+}
+
+// Manifest overrides the UnparsedImage.Manifest to always use the fields which we have already fetched.
+func (i *sourcedImage) Manifest() ([]byte, string, error) {
+	return i.manifestBlob, i.manifestMIMEType, nil
+}
+
+func (i *sourcedImage) Inspect() (*types.ImageInspectInfo, error) {
+	return inspectManifest(i.genericManifest)
+}
+
+func (i *sourcedImage) IsMultiImage() bool {
+	return i.manifestMIMEType == manifest.DockerV2ListMediaType
+}

vendor/src/github.com/containers/image/image/unparsed.go

@@ -0,0 +1,83 @@
+package image
+
+import (
+	"fmt"
+
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+)
+
+// UnparsedImage implements types.UnparsedImage .
+type UnparsedImage struct {
+	src            types.ImageSource
+	cachedManifest []byte // A private cache for Manifest(); nil if not yet known.
+	// A private cache for Manifest(), may be the empty string if guessing failed.
+	// Valid iff cachedManifest is not nil.
+	cachedManifestMIMEType string
+	cachedSignatures       [][]byte // A private cache for Signatures(); nil if not yet known.
+}
+
+// UnparsedFromSource returns a types.UnparsedImage implementation for source.
+// The caller must call .Close() on the returned UnparsedImage.
+//
+// UnparsedFromSource “takes ownership” of the input ImageSource and will call src.Close()
+// when the image is closed.  (This does not prevent callers from using both the
+// UnparsedImage and ImageSource objects simultaneously, but it means that they only need to
+// keep a reference to the UnparsedImage.)
+func UnparsedFromSource(src types.ImageSource) *UnparsedImage {
+	return &UnparsedImage{src: src}
+}
+
+// Reference returns the reference used to set up this source, _as specified by the user_
+// (not as the image itself, or its underlying storage, claims).  This can be used e.g. to determine which public keys are trusted for this image.
+func (i *UnparsedImage) Reference() types.ImageReference {
+	return i.src.Reference()
+}
+
+// Close removes resources associated with an initialized UnparsedImage, if any.
+func (i *UnparsedImage) Close() {
+	i.src.Close()
+}
+
+// Manifest is like ImageSource.GetManifest, but the result is cached; it is OK to call this however often you need.
+func (i *UnparsedImage) Manifest() ([]byte, string, error) {
+	if i.cachedManifest == nil {
+		m, mt, err := i.src.GetManifest()
+		if err != nil {
+			return nil, "", err
+		}
+
+		// ImageSource.GetManifest does not do digest verification, but we do;
+		// this immediately protects also any user of types.Image.
+		ref := i.Reference().DockerReference()
+		if ref != nil {
+			if canonical, ok := ref.(reference.Canonical); ok {
+				digest := canonical.Digest()
+				matches, err := manifest.MatchesDigest(m, digest)
+				if err != nil {
+					return nil, "", fmt.Errorf("Error computing manifest digest: %v", err)
+				}
+				if !matches {
+					return nil, "", fmt.Errorf("Manifest does not match provided manifest digest %s", digest)
+				}
+			}
+		}
+
+		i.cachedManifest = m
+		i.cachedManifestMIMEType = mt
+	}
+	return i.cachedManifest, i.cachedManifestMIMEType, nil
+}
+
+// Signatures is like ImageSource.GetSignatures, but the result is cached; it is OK to call this however often you need.
+func (i *UnparsedImage) Signatures() ([][]byte, error) {
+	if i.cachedSignatures == nil {
+		sigs, err := i.src.GetSignatures()
+		if err != nil {
+			return nil, err
+		}
+		i.cachedSignatures = sigs
+	}
+	return i.cachedSignatures, nil
+}

vendor/src/github.com/containers/image/manifest/manifest.go

@@ -1,10 +1,9 @@
 package manifest
 
 import (
-	"crypto/sha256"
-	"encoding/hex"
 	"encoding/json"
 
+	"github.com/docker/distribution/digest"
 	"github.com/docker/libtrust"
 	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
 )
@@ -19,8 +18,14 @@ const (
 	DockerV2Schema1SignedMediaType = "application/vnd.docker.distribution.manifest.v1+prettyjws"
 	// DockerV2Schema2MediaType MIME type represents Docker manifest schema 2
 	DockerV2Schema2MediaType = "application/vnd.docker.distribution.manifest.v2+json"
+	// DockerV2Schema2ConfigMediaType is the MIME type used for schema 2 config blobs.
+	DockerV2Schema2ConfigMediaType = "application/vnd.docker.container.image.v1+json"
+	// DockerV2Schema2LayerMediaType is the MIME type used for schema 2 layers.
+	DockerV2Schema2LayerMediaType = "application/vnd.docker.image.rootfs.diff.tar.gzip"
 	// DockerV2ListMediaType MIME type represents Docker manifest schema 2 list
 	DockerV2ListMediaType = "application/vnd.docker.distribution.manifest.list.v2+json"
+	// DockerV2Schema2ForeignLayerMediaType is the MIME type used for schema 2 foreign layers.
+	DockerV2Schema2ForeignLayerMediaType = "application/vnd.docker.image.rootfs.foreign.diff.tar.gzip"
 )
 
 // DefaultRequestedManifestMIMETypes is a list of MIME types a types.ImageSource
@@ -30,6 +35,7 @@ var DefaultRequestedManifestMIMETypes = []string{
 	DockerV2Schema2MediaType,
 	DockerV2Schema1SignedMediaType,
 	DockerV2Schema1MediaType,
+	DockerV2ListMediaType,
 }
 
 // GuessMIMEType guesses MIME type of a manifest and returns it _if it is recognized_, or "" if unknown or unrecognized.
@@ -65,7 +71,7 @@ func GuessMIMEType(manifest []byte) string {
 }
 
 // Digest returns the a digest of a docker manifest, with any necessary implied transformations like stripping v1s1 signatures.
-func Digest(manifest []byte) (string, error) {
+func Digest(manifest []byte) (digest.Digest, error) {
 	if GuessMIMEType(manifest) == DockerV2Schema1SignedMediaType {
 		sig, err := libtrust.ParsePrettySignature(manifest, "signatures")
 		if err != nil {
@@ -79,15 +85,14 @@ func Digest(manifest []byte) (string, error) {
 		}
 	}
 
-	hash := sha256.Sum256(manifest)
-	return "sha256:" + hex.EncodeToString(hash[:]), nil
+	return digest.FromBytes(manifest), nil
 }
 
 // MatchesDigest returns true iff the manifest matches expectedDigest.
 // Error may be set if this returns false.
 // Note that this is not doing ConstantTimeCompare; by the time we get here, the cryptographic signature must already have been verified,
 // or we are not using a cryptographic channel and the attacker can modify the digest along with the manifest blob.
-func MatchesDigest(manifest []byte, expectedDigest string) (bool, error) {
+func MatchesDigest(manifest []byte, expectedDigest digest.Digest) (bool, error) {
 	// This should eventually support various digest types.
 	actualDigest, err := Digest(manifest)
 	if err != nil {
@@ -95,3 +100,21 @@ func MatchesDigest(manifest []byte, expectedDigest string) (bool, error) {
 	}
 	return expectedDigest == actualDigest, nil
 }
+
+// AddDummyV2S1Signature adds an JWS signature with a temporary key (i.e. useless) to a v2s1 manifest.
+// This is useful to make the manifest acceptable to a Docker Registry (even though nothing needs or wants the JWS signature).
+func AddDummyV2S1Signature(manifest []byte) ([]byte, error) {
+	key, err := libtrust.GenerateECP256PrivateKey()
+	if err != nil {
+		return nil, err // Coverage: This can fail only if rand.Reader fails.
+	}
+
+	js, err := libtrust.NewJSONSignature(manifest)
+	if err != nil {
+		return nil, err
+	}
+	if err := js.Sign(key); err != nil { // Coverage: This can fail basically only if rand.Reader fails.
+		return nil, err
+	}
+	return js.PrettySignature("signatures")
+}

vendor/src/github.com/containers/image/oci/layout/oci_dest.go

@@ -1,8 +1,6 @@
 package layout
 
 import (
-	"crypto/sha256"
-	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -13,7 +11,7 @@ import (
 
 	"github.com/containers/image/manifest"
 	"github.com/containers/image/types"
-	imgspec "github.com/opencontainers/image-spec/specs-go"
+	"github.com/docker/distribution/digest"
 	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
@@ -49,19 +47,30 @@ func (d *ociImageDestination) SupportsSignatures() error {
 	return fmt.Errorf("Pushing signatures for OCI images is not supported")
 }
 
-// PutBlob writes contents of stream and returns its computed digest and size.
-// A digest can be optionally provided if known, the specific image destination can decide to play with it or not.
-// The length of stream is expected to be expectedSize; if expectedSize == -1, it is not known.
+// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination.
+func (d *ociImageDestination) ShouldCompressLayers() bool {
+	return true
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (d *ociImageDestination) AcceptsForeignLayerURLs() bool {
+	return false
+}
+
+// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+// inputInfo.Size is the expected length of stream, if known.
 // WARNING: The contents of stream are being verified on the fly.  Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
 // to any other readers for download using the supplied digest.
 // If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlob MUST 1) fail, and 2) delete any data stored so far.
-func (d *ociImageDestination) PutBlob(stream io.Reader, _ string, expectedSize int64) (string, int64, error) {
+func (d *ociImageDestination) PutBlob(stream io.Reader, inputInfo types.BlobInfo) (types.BlobInfo, error) {
 	if err := ensureDirectoryExists(d.ref.dir); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	blobFile, err := ioutil.TempFile(d.ref.dir, "oci-put-blob")
 	if err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	succeeded := false
 	defer func() {
@@ -71,36 +80,58 @@ func (d *ociImageDestination) PutBlob(stream io.Reader, _ string, expectedSize i
 		}
 	}()
 
-	h := sha256.New()
-	tee := io.TeeReader(stream, h)
+	digester := digest.Canonical.New()
+	tee := io.TeeReader(stream, digester.Hash())
 
 	size, err := io.Copy(blobFile, tee)
 	if err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
-	computedDigest := "sha256:" + hex.EncodeToString(h.Sum(nil))
-	if expectedSize != -1 && size != expectedSize {
-		return "", -1, fmt.Errorf("Size mismatch when copying %s, expected %d, got %d", computedDigest, expectedSize, size)
+	computedDigest := digester.Digest()
+	if inputInfo.Size != -1 && size != inputInfo.Size {
+		return types.BlobInfo{}, fmt.Errorf("Size mismatch when copying %s, expected %d, got %d", computedDigest, inputInfo.Size, size)
 	}
 	if err := blobFile.Sync(); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	if err := blobFile.Chmod(0644); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 
 	blobPath, err := d.ref.blobPath(computedDigest)
 	if err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	if err := ensureParentDirectoryExists(blobPath); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	if err := os.Rename(blobFile.Name(), blobPath); err != nil {
-		return "", -1, err
+		return types.BlobInfo{}, err
 	}
 	succeeded = true
-	return computedDigest, size, nil
+	return types.BlobInfo{Digest: computedDigest, Size: size}, nil
+}
+
+func (d *ociImageDestination) HasBlob(info types.BlobInfo) (bool, int64, error) {
+	if info.Digest == "" {
+		return false, -1, fmt.Errorf(`"Can not check for a blob with unknown digest`)
+	}
+	blobPath, err := d.ref.blobPath(info.Digest)
+	if err != nil {
+		return false, -1, err
+	}
+	finfo, err := os.Stat(blobPath)
+	if err != nil && os.IsNotExist(err) {
+		return false, -1, types.ErrBlobNotFound
+	}
+	if err != nil {
+		return false, -1, err
+	}
+	return true, finfo.Size(), nil
+}
+
+func (d *ociImageDestination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
+	return info, nil
 }
 
 func createManifest(m []byte) ([]byte, string, error) {
@@ -118,8 +149,12 @@ func createManifest(m []byte) ([]byte, string, error) {
 			return nil, "", err
 		}
 		om.MediaType = imgspecv1.MediaTypeImageManifest
-		for i := range om.Layers {
-			om.Layers[i].MediaType = imgspecv1.MediaTypeImageLayer
+		for i, l := range om.Layers {
+			if l.MediaType == manifest.DockerV2Schema2ForeignLayerMediaType {
+				om.Layers[i].MediaType = imgspecv1.MediaTypeImageLayerNonDistributable
+			} else {
+				om.Layers[i].MediaType = imgspecv1.MediaTypeImageLayer
+			}
 		}
 		om.Config.MediaType = imgspecv1.MediaTypeImageConfig
 		b, err := json.Marshal(om)
@@ -148,8 +183,8 @@ func (d *ociImageDestination) PutManifest(m []byte) error {
 	if err != nil {
 		return err
 	}
-	desc := imgspec.Descriptor{}
-	desc.Digest = digest
+	desc := imgspecv1.Descriptor{}
+	desc.Digest = digest.String()
 	// TODO(runcom): beaware and add support for OCI manifest list
 	desc.MediaType = mt
 	desc.Size = int64(len(ociMan))

vendor/src/github.com/containers/image/oci/layout/oci_src.go

@@ -0,0 +1,94 @@
+package layout
+
+import (
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"os"
+
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+type ociImageSource struct {
+	ref ociReference
+}
+
+// newImageSource returns an ImageSource for reading from an existing directory.
+func newImageSource(ref ociReference) types.ImageSource {
+	return &ociImageSource{ref: ref}
+}
+
+// Reference returns the reference used to set up this source.
+func (s *ociImageSource) Reference() types.ImageReference {
+	return s.ref
+}
+
+// Close removes resources associated with an initialized ImageSource, if any.
+func (s *ociImageSource) Close() {
+}
+
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
+func (s *ociImageSource) GetManifest() ([]byte, string, error) {
+	descriptorPath := s.ref.descriptorPath(s.ref.tag)
+	data, err := ioutil.ReadFile(descriptorPath)
+	if err != nil {
+		return nil, "", err
+	}
+
+	desc := imgspecv1.Descriptor{}
+	err = json.Unmarshal(data, &desc)
+	if err != nil {
+		return nil, "", err
+	}
+
+	manifestPath, err := s.ref.blobPath(digest.Digest(desc.Digest))
+	if err != nil {
+		return nil, "", err
+	}
+	m, err := ioutil.ReadFile(manifestPath)
+	if err != nil {
+		return nil, "", err
+	}
+
+	return m, manifest.GuessMIMEType(m), nil
+}
+
+func (s *ociImageSource) GetTargetManifest(digest digest.Digest) ([]byte, string, error) {
+	manifestPath, err := s.ref.blobPath(digest)
+	if err != nil {
+		return nil, "", err
+	}
+
+	m, err := ioutil.ReadFile(manifestPath)
+	if err != nil {
+		return nil, "", err
+	}
+
+	return m, manifest.GuessMIMEType(m), nil
+}
+
+// GetBlob returns a stream for the specified blob, and the blob's size.
+func (s *ociImageSource) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
+	path, err := s.ref.blobPath(info.Digest)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	r, err := os.Open(path)
+	if err != nil {
+		return nil, 0, err
+	}
+	fi, err := r.Stat()
+	if err != nil {
+		return nil, 0, err
+	}
+	return r, fi.Size(), nil
+}
+
+func (s *ociImageSource) GetSignatures() ([][]byte, error) {
+	return [][]byte{}, nil
+}

vendor/src/github.com/containers/image/oci/layout/oci_transport.go

@@ -8,8 +8,10 @@ import (
 	"strings"
 
 	"github.com/containers/image/directory/explicitfilepath"
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/image"
 	"github.com/containers/image/types"
-	"github.com/docker/docker/reference"
+	"github.com/docker/distribution/digest"
 )
 
 // Transport is an ImageTransport for OCI directories.
@@ -164,10 +166,13 @@ func (ref ociReference) PolicyConfigurationNamespaces() []string {
 	return res
 }
 
-// NewImage returns a types.Image for this reference.
+// NewImage returns a types.Image for this reference, possibly specialized for this ImageTransport.
 // The caller must call .Close() on the returned Image.
+// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage.
 func (ref ociReference) NewImage(ctx *types.SystemContext) (types.Image, error) {
-	return nil, errors.New("Full Image support not implemented for oci: image names")
+	src := newImageSource(ref)
+	return image.FromSource(src)
 }
 
 // NewImageSource returns a types.ImageSource for this reference,
@@ -175,7 +180,7 @@ func (ref ociReference) NewImage(ctx *types.SystemContext) (types.Image, error)
 // nil requestedManifestMIMETypes means manifest.DefaultRequestedManifestMIMETypes.
 // The caller must call .Close() on the returned ImageSource.
 func (ref ociReference) NewImageSource(ctx *types.SystemContext, requestedManifestMIMETypes []string) (types.ImageSource, error) {
-	return nil, errors.New("Reading images not implemented for oci: image names")
+	return newImageSource(ref), nil
 }
 
 // NewImageDestination returns a types.ImageDestination for this reference.
@@ -195,12 +200,11 @@ func (ref ociReference) ociLayoutPath() string {
 }
 
 // blobPath returns a path for a blob within a directory using OCI image-layout conventions.
-func (ref ociReference) blobPath(digest string) (string, error) {
-	pts := strings.SplitN(digest, ":", 2)
-	if len(pts) != 2 {
-		return "", fmt.Errorf("unexpected digest reference %s", digest)
+func (ref ociReference) blobPath(digest digest.Digest) (string, error) {
+	if err := digest.Validate(); err != nil {
+		return "", fmt.Errorf("unexpected digest reference %s: %v", digest, err)
 	}
-	return filepath.Join(ref.dir, "blobs", pts[0], pts[1]), nil
+	return filepath.Join(ref.dir, "blobs", digest.Algorithm().String(), digest.Hex()), nil
 }
 
 // descriptorPath returns a path for the manifest within a directory using OCI conventions.

vendor/src/github.com/containers/image/openshift/openshift.go

@@ -11,13 +11,13 @@ import (
 	"net/http"
 	"net/url"
 	"strings"
-	"time"
 
 	"github.com/Sirupsen/logrus"
 	"github.com/containers/image/docker"
 	"github.com/containers/image/manifest"
 	"github.com/containers/image/types"
 	"github.com/containers/image/version"
+	"github.com/docker/distribution/digest"
 )
 
 // openshiftClient is configuration for dealing with a single image stream, for reading or writing.
@@ -57,7 +57,6 @@ func newOpenshiftClient(ref openshiftReference) (*openshiftClient, error) {
 	if httpClient == nil {
 		httpClient = http.DefaultClient
 	}
-	httpClient.Timeout = 1 * time.Minute
 
 	return &openshiftClient{
 		ref:         ref,
@@ -198,6 +197,15 @@ func (s *openshiftImageSource) Close() {
 	}
 }
 
+func (s *openshiftImageSource) GetTargetManifest(digest digest.Digest) ([]byte, string, error) {
+	if err := s.ensureImageIsResolved(); err != nil {
+		return nil, "", err
+	}
+	return s.docker.GetTargetManifest(digest)
+}
+
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
 func (s *openshiftImageSource) GetManifest() ([]byte, string, error) {
 	if err := s.ensureImageIsResolved(); err != nil {
 		return nil, "", err
@@ -206,11 +214,11 @@ func (s *openshiftImageSource) GetManifest() ([]byte, string, error) {
 }
 
 // GetBlob returns a stream for the specified blob, and the blob’s size (or -1 if unknown).
-func (s *openshiftImageSource) GetBlob(digest string) (io.ReadCloser, int64, error) {
+func (s *openshiftImageSource) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
 	if err := s.ensureImageIsResolved(); err != nil {
 		return nil, 0, err
 	}
-	return s.docker.GetBlob(digest)
+	return s.docker.GetBlob(info)
 }
 
 func (s *openshiftImageSource) GetSignatures() ([][]byte, error) {
@@ -337,60 +345,43 @@ func (d *openshiftImageDestination) SupportsSignatures() error {
 	return nil
 }
 
-// PutBlob writes contents of stream and returns its computed digest and size.
-// A digest can be optionally provided if known, the specific image destination can decide to play with it or not.
-// The length of stream is expected to be expectedSize; if expectedSize == -1, it is not known.
+// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination.
+func (d *openshiftImageDestination) ShouldCompressLayers() bool {
+	return true
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (d *openshiftImageDestination) AcceptsForeignLayerURLs() bool {
+	return true
+}
+
+// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+// inputInfo.Size is the expected length of stream, if known.
 // WARNING: The contents of stream are being verified on the fly.  Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
 // to any other readers for download using the supplied digest.
 // If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlob MUST 1) fail, and 2) delete any data stored so far.
-func (d *openshiftImageDestination) PutBlob(stream io.Reader, digest string, expectedSize int64) (string, int64, error) {
-	return d.docker.PutBlob(stream, digest, expectedSize)
+func (d *openshiftImageDestination) PutBlob(stream io.Reader, inputInfo types.BlobInfo) (types.BlobInfo, error) {
+	return d.docker.PutBlob(stream, inputInfo)
+}
+
+func (d *openshiftImageDestination) HasBlob(info types.BlobInfo) (bool, int64, error) {
+	return d.docker.HasBlob(info)
+}
+
+func (d *openshiftImageDestination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
+	return d.docker.ReapplyBlob(info)
 }
 
 func (d *openshiftImageDestination) PutManifest(m []byte) error {
-	// FIXME? Can this eventually just call d.docker.PutManifest()?
-	// Right now we need this as a skeleton to attach signatures to, and
-	// to workaround our inability to change tags when uploading v2s1 manifests.
-
-	// Note: This does absolutely no kind/version checking or conversions.
 	manifestDigest, err := manifest.Digest(m)
 	if err != nil {
 		return err
 	}
-	d.imageStreamImageName = manifestDigest
-	// FIXME: We can't do what respositorymiddleware.go does because we don't know the internal address. Does any of this matter?
-	dockerImageReference := fmt.Sprintf("%s/%s/%s@%s", d.client.ref.dockerReference.Hostname(), d.client.ref.namespace, d.client.ref.stream, manifestDigest)
-	ism := imageStreamMapping{
-		typeMeta: typeMeta{
-			Kind:       "ImageStreamMapping",
-			APIVersion: "v1",
-		},
-		objectMeta: objectMeta{
-			Namespace: d.client.ref.namespace,
-			Name:      d.client.ref.stream,
-		},
-		Image: image{
-			objectMeta: objectMeta{
-				Name: manifestDigest,
-			},
-			DockerImageReference: dockerImageReference,
-			DockerImageManifest:  string(m),
-		},
-		Tag: d.client.ref.dockerReference.Tag(),
-	}
-	body, err := json.Marshal(ism)
-	if err != nil {
-		return err
-	}
+	d.imageStreamImageName = manifestDigest.String()
 
-	// FIXME: validate components per validation.IsValidPathSegmentName?
-	path := fmt.Sprintf("/oapi/v1/namespaces/%s/imagestreammappings", d.client.ref.namespace)
-	body, err = d.client.doRequest("POST", path, body)
-	if err != nil {
-		return err
-	}
-
-	return nil
+	return d.docker.PutManifest(m)
 }
 
 func (d *openshiftImageDestination) PutSignatures(signatures [][]byte) error {
@@ -505,12 +496,6 @@ type imageSignature struct {
 	// IssuedBy SignatureIssuer `json:"issuedBy,omitempty"`
 	// IssuedTo SignatureSubject `json:"issuedTo,omitempty"`
 }
-type imageStreamMapping struct {
-	typeMeta   `json:",inline"`
-	objectMeta `json:"metadata,omitempty"`
-	Image      image  `json:"image"`
-	Tag        string `json:"tag"`
-}
 type typeMeta struct {
 	Kind       string `json:"kind,omitempty"`
 	APIVersion string `json:"apiVersion,omitempty"`

vendor/src/github.com/containers/image/openshift/openshift_transport.go

@@ -1,14 +1,14 @@
 package openshift
 
 import (
-	"errors"
 	"fmt"
 	"regexp"
 	"strings"
 
 	"github.com/containers/image/docker/policyconfiguration"
+	"github.com/containers/image/docker/reference"
+	genericImage "github.com/containers/image/image"
 	"github.com/containers/image/types"
-	"github.com/docker/docker/reference"
 )
 
 // Transport is an ImageTransport for OpenShift registry-hosted images.
@@ -118,10 +118,16 @@ func (ref openshiftReference) PolicyConfigurationNamespaces() []string {
 	return policyconfiguration.DockerReferenceNamespaces(ref.dockerReference)
 }
 
-// NewImage returns a types.Image for this reference.
+// NewImage returns a types.Image for this reference, possibly specialized for this ImageTransport.
 // The caller must call .Close() on the returned Image.
+// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage.
 func (ref openshiftReference) NewImage(ctx *types.SystemContext) (types.Image, error) {
-	return nil, errors.New("Full Image support not implemented for atomic: image names")
+	src, err := newImageSource(ctx, ref, nil)
+	if err != nil {
+		return nil, err
+	}
+	return genericImage.FromSource(src)
 }
 
 // NewImageSource returns a types.ImageSource for this reference,

vendor/src/github.com/containers/image/signature/docker.go

@@ -0,0 +1,61 @@
+// Note: Consider the API unstable until the code supports at least three different image formats or transports.
+
+package signature
+
+import (
+	"fmt"
+
+	"github.com/containers/image/manifest"
+	"github.com/docker/distribution/digest"
+)
+
+// SignDockerManifest returns a signature for manifest as the specified dockerReference,
+// using mech and keyIdentity.
+func SignDockerManifest(m []byte, dockerReference string, mech SigningMechanism, keyIdentity string) ([]byte, error) {
+	manifestDigest, err := manifest.Digest(m)
+	if err != nil {
+		return nil, err
+	}
+	sig := privateSignature{
+		Signature{
+			DockerManifestDigest: manifestDigest,
+			DockerReference:      dockerReference,
+		},
+	}
+	return sig.sign(mech, keyIdentity)
+}
+
+// VerifyDockerManifestSignature checks that unverifiedSignature uses expectedKeyIdentity to sign unverifiedManifest as expectedDockerReference,
+// using mech.
+func VerifyDockerManifestSignature(unverifiedSignature, unverifiedManifest []byte,
+	expectedDockerReference string, mech SigningMechanism, expectedKeyIdentity string) (*Signature, error) {
+	sig, err := verifyAndExtractSignature(mech, unverifiedSignature, signatureAcceptanceRules{
+		validateKeyIdentity: func(keyIdentity string) error {
+			if keyIdentity != expectedKeyIdentity {
+				return InvalidSignatureError{msg: fmt.Sprintf("Signature by %s does not match expected fingerprint %s", keyIdentity, expectedKeyIdentity)}
+			}
+			return nil
+		},
+		validateSignedDockerReference: func(signedDockerReference string) error {
+			if signedDockerReference != expectedDockerReference {
+				return InvalidSignatureError{msg: fmt.Sprintf("Docker reference %s does not match %s",
+					signedDockerReference, expectedDockerReference)}
+			}
+			return nil
+		},
+		validateSignedDockerManifestDigest: func(signedDockerManifestDigest digest.Digest) error {
+			matches, err := manifest.MatchesDigest(unverifiedManifest, signedDockerManifestDigest)
+			if err != nil {
+				return err
+			}
+			if !matches {
+				return InvalidSignatureError{msg: fmt.Sprintf("Signature for docker digest %q does not match", signedDockerManifestDigest)}
+			}
+			return nil
+		},
+	})
+	if err != nil {
+		return nil, err
+	}
+	return sig, nil
+}

vendor/src/github.com/containers/image/signature/json.go

@@ -0,0 +1,107 @@
+package signature
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+)
+
+// jsonFormatError is returned when JSON does not match expected format.
+type jsonFormatError string
+
+func (err jsonFormatError) Error() string {
+	return string(err)
+}
+
+// validateExactMapKeys returns an error if the keys of m are not exactly expectedKeys, which must be pairwise distinct
+func validateExactMapKeys(m map[string]interface{}, expectedKeys ...string) error {
+	if len(m) != len(expectedKeys) {
+		return jsonFormatError("Unexpected keys in a JSON object")
+	}
+
+	for _, k := range expectedKeys {
+		if _, ok := m[k]; !ok {
+			return jsonFormatError(fmt.Sprintf("Key %s missing in a JSON object", k))
+		}
+	}
+	// Assuming expectedKeys are pairwise distinct, we know m contains len(expectedKeys) different values in expectedKeys.
+	return nil
+}
+
+// mapField returns a member fieldName of m, if it is a JSON map, or an error.
+func mapField(m map[string]interface{}, fieldName string) (map[string]interface{}, error) {
+	untyped, ok := m[fieldName]
+	if !ok {
+		return nil, jsonFormatError(fmt.Sprintf("Field %s missing", fieldName))
+	}
+	v, ok := untyped.(map[string]interface{})
+	if !ok {
+		return nil, jsonFormatError(fmt.Sprintf("Field %s is not a JSON object", fieldName))
+	}
+	return v, nil
+}
+
+// stringField returns a member fieldName of m, if it is a string, or an error.
+func stringField(m map[string]interface{}, fieldName string) (string, error) {
+	untyped, ok := m[fieldName]
+	if !ok {
+		return "", jsonFormatError(fmt.Sprintf("Field %s missing", fieldName))
+	}
+	v, ok := untyped.(string)
+	if !ok {
+		return "", jsonFormatError(fmt.Sprintf("Field %s is not a JSON object", fieldName))
+	}
+	return v, nil
+}
+
+// paranoidUnmarshalJSONObject unmarshals data as a JSON object, but failing on the slightest unexpected aspect
+// (including duplicated keys, unrecognized keys, and non-matching types). Uses fieldResolver to
+// determine the destination for a field value, which should return a pointer to the destination if valid, or nil if the key is rejected.
+//
+// The fieldResolver approach is useful for decoding the Policy.Transports map; using it for structs is a bit lazy,
+// we could use reflection to automate this. Later?
+func paranoidUnmarshalJSONObject(data []byte, fieldResolver func(string) interface{}) error {
+	seenKeys := map[string]struct{}{}
+
+	dec := json.NewDecoder(bytes.NewReader(data))
+	t, err := dec.Token()
+	if err != nil {
+		return jsonFormatError(err.Error())
+	}
+	if t != json.Delim('{') {
+		return jsonFormatError(fmt.Sprintf("JSON object expected, got \"%s\"", t))
+	}
+	for {
+		t, err := dec.Token()
+		if err != nil {
+			return jsonFormatError(err.Error())
+		}
+		if t == json.Delim('}') {
+			break
+		}
+
+		key, ok := t.(string)
+		if !ok {
+			// Coverage: This should never happen, dec.Token() rejects non-string-literals in this state.
+			return jsonFormatError(fmt.Sprintf("Key string literal expected, got \"%s\"", t))
+		}
+		if _, ok := seenKeys[key]; ok {
+			return jsonFormatError(fmt.Sprintf("Duplicate key \"%s\"", key))
+		}
+		seenKeys[key] = struct{}{}
+
+		valuePtr := fieldResolver(key)
+		if valuePtr == nil {
+			return jsonFormatError(fmt.Sprintf("Unknown key \"%s\"", key))
+		}
+		// This works like json.Unmarshal, in particular it allows us to implement UnmarshalJSON to implement strict parsing of the field value.
+		if err := dec.Decode(valuePtr); err != nil {
+			return jsonFormatError(err.Error())
+		}
+	}
+	if _, err := dec.Token(); err != io.EOF {
+		return jsonFormatError("Unexpected data after JSON object")
+	}
+	return nil
+}

vendor/src/github.com/containers/image/signature/mechanism.go

@@ -0,0 +1,124 @@
+// Note: Consider the API unstable until the code supports at least three different image formats or transports.
+
+package signature
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/mtrmac/gpgme"
+)
+
+// SigningMechanism abstracts a way to sign binary blobs and verify their signatures.
+// FIXME: Eventually expand on keyIdentity (namespace them between mechanisms to
+// eliminate ambiguities, support CA signatures and perhaps other key properties)
+type SigningMechanism interface {
+	// ImportKeysFromBytes imports public keys from the supplied blob and returns their identities.
+	// The blob is assumed to have an appropriate format (the caller is expected to know which one).
+	// NOTE: This may modify long-term state (e.g. key storage in a directory underlying the mechanism).
+	ImportKeysFromBytes(blob []byte) ([]string, error)
+	// Sign creates a (non-detached) signature of input using keyidentity
+	Sign(input []byte, keyIdentity string) ([]byte, error)
+	// Verify parses unverifiedSignature and returns the content and the signer's identity
+	Verify(unverifiedSignature []byte) (contents []byte, keyIdentity string, err error)
+}
+
+// A GPG/OpenPGP signing mechanism.
+type gpgSigningMechanism struct {
+	ctx *gpgme.Context
+}
+
+// NewGPGSigningMechanism returns a new GPG/OpenPGP signing mechanism.
+func NewGPGSigningMechanism() (SigningMechanism, error) {
+	return newGPGSigningMechanismInDirectory("")
+}
+
+// newGPGSigningMechanismInDirectory returns a new GPG/OpenPGP signing mechanism, using optionalDir if not empty.
+func newGPGSigningMechanismInDirectory(optionalDir string) (SigningMechanism, error) {
+	ctx, err := gpgme.New()
+	if err != nil {
+		return nil, err
+	}
+	if err = ctx.SetProtocol(gpgme.ProtocolOpenPGP); err != nil {
+		return nil, err
+	}
+	if optionalDir != "" {
+		err := ctx.SetEngineInfo(gpgme.ProtocolOpenPGP, "", optionalDir)
+		if err != nil {
+			return nil, err
+		}
+	}
+	ctx.SetArmor(false)
+	ctx.SetTextMode(false)
+	return gpgSigningMechanism{ctx: ctx}, nil
+}
+
+// ImportKeysFromBytes implements SigningMechanism.ImportKeysFromBytes
+func (m gpgSigningMechanism) ImportKeysFromBytes(blob []byte) ([]string, error) {
+	inputData, err := gpgme.NewDataBytes(blob)
+	if err != nil {
+		return nil, err
+	}
+	res, err := m.ctx.Import(inputData)
+	if err != nil {
+		return nil, err
+	}
+	keyIdentities := []string{}
+	for _, i := range res.Imports {
+		if i.Result == nil {
+			keyIdentities = append(keyIdentities, i.Fingerprint)
+		}
+	}
+	return keyIdentities, nil
+}
+
+// Sign implements SigningMechanism.Sign
+func (m gpgSigningMechanism) Sign(input []byte, keyIdentity string) ([]byte, error) {
+	key, err := m.ctx.GetKey(keyIdentity, true)
+	if err != nil {
+		if e, ok := err.(gpgme.Error); ok && e.Code() == gpgme.ErrorEOF {
+			return nil, fmt.Errorf("key %q not found", keyIdentity)
+		}
+		return nil, err
+	}
+	inputData, err := gpgme.NewDataBytes(input)
+	if err != nil {
+		return nil, err
+	}
+	var sigBuffer bytes.Buffer
+	sigData, err := gpgme.NewDataWriter(&sigBuffer)
+	if err != nil {
+		return nil, err
+	}
+	if err = m.ctx.Sign([]*gpgme.Key{key}, inputData, sigData, gpgme.SigModeNormal); err != nil {
+		return nil, err
+	}
+	return sigBuffer.Bytes(), nil
+}
+
+// Verify implements SigningMechanism.Verify
+func (m gpgSigningMechanism) Verify(unverifiedSignature []byte) (contents []byte, keyIdentity string, err error) {
+	signedBuffer := bytes.Buffer{}
+	signedData, err := gpgme.NewDataWriter(&signedBuffer)
+	if err != nil {
+		return nil, "", err
+	}
+	unverifiedSignatureData, err := gpgme.NewDataBytes(unverifiedSignature)
+	if err != nil {
+		return nil, "", err
+	}
+	_, sigs, err := m.ctx.Verify(unverifiedSignatureData, nil, signedData)
+	if err != nil {
+		return nil, "", err
+	}
+	if len(sigs) != 1 {
+		return nil, "", InvalidSignatureError{msg: fmt.Sprintf("Unexpected GPG signature count %d", len(sigs))}
+	}
+	sig := sigs[0]
+	// This is sig.Summary == gpgme.SigSumValid except for key trust, which we handle ourselves
+	if sig.Status != nil || sig.Validity == gpgme.ValidityNever || sig.ValidityReason != nil || sig.WrongKeyUsage {
+		// FIXME: Better error reporting eventually
+		return nil, "", InvalidSignatureError{msg: fmt.Sprintf("Invalid GPG signature: %#v", sig)}
+	}
+	return signedBuffer.Bytes(), sig.Fingerprint, nil
+}

vendor/src/github.com/containers/image/signature/policy_config.go

@@ -0,0 +1,732 @@
+// policy_config.go hanles creation of policy objects, either by parsing JSON
+// or by programs building them programmatically.
+
+// The New* constructors are intended to be a stable API. FIXME: after an independent review.
+
+// Do not invoke the internals of the JSON marshaling/unmarshaling directly.
+
+// We can't just blindly call json.Unmarshal because that would silently ignore
+// typos, and that would just not do for security policy.
+
+// FIXME? This is by no means an user-friendly parser: No location information in error messages, no other context.
+// But at least it is not worse than blind json.Unmarshal()…
+
+package signature
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/transports"
+	"github.com/containers/image/types"
+)
+
+// systemDefaultPolicyPath is the policy path used for DefaultPolicy().
+// You can override this at build time with
+// -ldflags '-X github.com/containers/image/signature.systemDefaultPolicyPath=$your_path'
+var systemDefaultPolicyPath = builtinDefaultPolicyPath
+
+// builtinDefaultPolicyPath is the policy pat used for DefaultPolicy().
+// DO NOT change this, instead see systemDefaultPolicyPath above.
+const builtinDefaultPolicyPath = "/etc/containers/policy.json"
+
+// InvalidPolicyFormatError is returned when parsing an invalid policy configuration.
+type InvalidPolicyFormatError string
+
+func (err InvalidPolicyFormatError) Error() string {
+	return string(err)
+}
+
+// DefaultPolicy returns the default policy of the system.
+// Most applications should be using this method to get the policy configured
+// by the system administrator.
+// ctx should usually be nil, can be set to override the default.
+// NOTE: When this function returns an error, report it to the user and abort.
+// DO NOT hard-code fallback policies in your application.
+func DefaultPolicy(ctx *types.SystemContext) (*Policy, error) {
+	return NewPolicyFromFile(defaultPolicyPath(ctx))
+}
+
+// defaultPolicyPath returns a path to the default policy of the system.
+func defaultPolicyPath(ctx *types.SystemContext) string {
+	if ctx != nil {
+		if ctx.SignaturePolicyPath != "" {
+			return ctx.SignaturePolicyPath
+		}
+		if ctx.RootForImplicitAbsolutePaths != "" {
+			return filepath.Join(ctx.RootForImplicitAbsolutePaths, systemDefaultPolicyPath)
+		}
+	}
+	return systemDefaultPolicyPath
+}
+
+// NewPolicyFromFile returns a policy configured in the specified file.
+func NewPolicyFromFile(fileName string) (*Policy, error) {
+	contents, err := ioutil.ReadFile(fileName)
+	if err != nil {
+		return nil, err
+	}
+	return NewPolicyFromBytes(contents)
+}
+
+// NewPolicyFromBytes returns a policy parsed from the specified blob.
+// Use this function instead of calling json.Unmarshal directly.
+func NewPolicyFromBytes(data []byte) (*Policy, error) {
+	p := Policy{}
+	if err := json.Unmarshal(data, &p); err != nil {
+		return nil, InvalidPolicyFormatError(err.Error())
+	}
+	return &p, nil
+}
+
+// Compile-time check that Policy implements json.Unmarshaler.
+var _ json.Unmarshaler = (*Policy)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (p *Policy) UnmarshalJSON(data []byte) error {
+	*p = Policy{}
+	transports := policyTransportsMap{}
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "default":
+			return &p.Default
+		case "transports":
+			return &transports
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if p.Default == nil {
+		return InvalidPolicyFormatError("Default policy is missing")
+	}
+	p.Transports = map[string]PolicyTransportScopes(transports)
+	return nil
+}
+
+// policyTransportsMap is a specialization of this map type for the strict JSON parsing semantics appropriate for the Policy.Transports member.
+type policyTransportsMap map[string]PolicyTransportScopes
+
+// Compile-time check that policyTransportsMap implements json.Unmarshaler.
+var _ json.Unmarshaler = (*policyTransportsMap)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (m *policyTransportsMap) UnmarshalJSON(data []byte) error {
+	// We can't unmarshal directly into map values because it is not possible to take an address of a map value.
+	// So, use a temporary map of pointers-to-slices and convert.
+	tmpMap := map[string]*PolicyTransportScopes{}
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		transport, ok := transports.KnownTransports[key]
+		if !ok {
+			return nil
+		}
+		// paranoidUnmarshalJSONObject detects key duplication for us, check just to be safe.
+		if _, ok := tmpMap[key]; ok {
+			return nil
+		}
+		ptsWithTransport := policyTransportScopesWithTransport{
+			transport: transport,
+			dest:      &PolicyTransportScopes{}, // This allocates a new instance on each call.
+		}
+		tmpMap[key] = ptsWithTransport.dest
+		return &ptsWithTransport
+	}); err != nil {
+		return err
+	}
+	for key, ptr := range tmpMap {
+		(*m)[key] = *ptr
+	}
+	return nil
+}
+
+// Compile-time check that PolicyTransportScopes "implements"" json.Unmarshaler.
+// we want to only use policyTransportScopesWithTransport
+var _ json.Unmarshaler = (*PolicyTransportScopes)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (m *PolicyTransportScopes) UnmarshalJSON(data []byte) error {
+	return errors.New("Do not try to unmarshal PolicyTransportScopes directly")
+}
+
+// policyTransportScopesWithTransport is a way to unmarshal a PolicyTransportScopes
+// while validating using a specific ImageTransport.
+type policyTransportScopesWithTransport struct {
+	transport types.ImageTransport
+	dest      *PolicyTransportScopes
+}
+
+// Compile-time check that policyTransportScopesWithTransport implements json.Unmarshaler.
+var _ json.Unmarshaler = (*policyTransportScopesWithTransport)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (m *policyTransportScopesWithTransport) UnmarshalJSON(data []byte) error {
+	// We can't unmarshal directly into map values because it is not possible to take an address of a map value.
+	// So, use a temporary map of pointers-to-slices and convert.
+	tmpMap := map[string]*PolicyRequirements{}
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		// paranoidUnmarshalJSONObject detects key duplication for us, check just to be safe.
+		if _, ok := tmpMap[key]; ok {
+			return nil
+		}
+		if key != "" {
+			if err := m.transport.ValidatePolicyConfigurationScope(key); err != nil {
+				return nil
+			}
+		}
+		ptr := &PolicyRequirements{} // This allocates a new instance on each call.
+		tmpMap[key] = ptr
+		return ptr
+	}); err != nil {
+		return err
+	}
+	for key, ptr := range tmpMap {
+		(*m.dest)[key] = *ptr
+	}
+	return nil
+}
+
+// Compile-time check that PolicyRequirements implements json.Unmarshaler.
+var _ json.Unmarshaler = (*PolicyRequirements)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (m *PolicyRequirements) UnmarshalJSON(data []byte) error {
+	reqJSONs := []json.RawMessage{}
+	if err := json.Unmarshal(data, &reqJSONs); err != nil {
+		return err
+	}
+	if len(reqJSONs) == 0 {
+		return InvalidPolicyFormatError("List of verification policy requirements must not be empty")
+	}
+	res := make([]PolicyRequirement, len(reqJSONs))
+	for i, reqJSON := range reqJSONs {
+		req, err := newPolicyRequirementFromJSON(reqJSON)
+		if err != nil {
+			return err
+		}
+		res[i] = req
+	}
+	*m = res
+	return nil
+}
+
+// newPolicyRequirementFromJSON parses JSON data into a PolicyRequirement implementation.
+func newPolicyRequirementFromJSON(data []byte) (PolicyRequirement, error) {
+	var typeField prCommon
+	if err := json.Unmarshal(data, &typeField); err != nil {
+		return nil, err
+	}
+	var res PolicyRequirement
+	switch typeField.Type {
+	case prTypeInsecureAcceptAnything:
+		res = &prInsecureAcceptAnything{}
+	case prTypeReject:
+		res = &prReject{}
+	case prTypeSignedBy:
+		res = &prSignedBy{}
+	case prTypeSignedBaseLayer:
+		res = &prSignedBaseLayer{}
+	default:
+		return nil, InvalidPolicyFormatError(fmt.Sprintf("Unknown policy requirement type \"%s\"", typeField.Type))
+	}
+	if err := json.Unmarshal(data, &res); err != nil {
+		return nil, err
+	}
+	return res, nil
+}
+
+// newPRInsecureAcceptAnything is NewPRInsecureAcceptAnything, except it returns the private type.
+func newPRInsecureAcceptAnything() *prInsecureAcceptAnything {
+	return &prInsecureAcceptAnything{prCommon{Type: prTypeInsecureAcceptAnything}}
+}
+
+// NewPRInsecureAcceptAnything returns a new "insecureAcceptAnything" PolicyRequirement.
+func NewPRInsecureAcceptAnything() PolicyRequirement {
+	return newPRInsecureAcceptAnything()
+}
+
+// Compile-time check that prInsecureAcceptAnything implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prInsecureAcceptAnything)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (pr *prInsecureAcceptAnything) UnmarshalJSON(data []byte) error {
+	*pr = prInsecureAcceptAnything{}
+	var tmp prInsecureAcceptAnything
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prTypeInsecureAcceptAnything {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+	*pr = *newPRInsecureAcceptAnything()
+	return nil
+}
+
+// newPRReject is NewPRReject, except it returns the private type.
+func newPRReject() *prReject {
+	return &prReject{prCommon{Type: prTypeReject}}
+}
+
+// NewPRReject returns a new "reject" PolicyRequirement.
+func NewPRReject() PolicyRequirement {
+	return newPRReject()
+}
+
+// Compile-time check that prReject implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prReject)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (pr *prReject) UnmarshalJSON(data []byte) error {
+	*pr = prReject{}
+	var tmp prReject
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prTypeReject {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+	*pr = *newPRReject()
+	return nil
+}
+
+// newPRSignedBy returns a new prSignedBy if parameters are valid.
+func newPRSignedBy(keyType sbKeyType, keyPath string, keyData []byte, signedIdentity PolicyReferenceMatch) (*prSignedBy, error) {
+	if !keyType.IsValid() {
+		return nil, InvalidPolicyFormatError(fmt.Sprintf("invalid keyType \"%s\"", keyType))
+	}
+	if len(keyPath) > 0 && len(keyData) > 0 {
+		return nil, InvalidPolicyFormatError("keyType and keyData cannot be used simultaneously")
+	}
+	if signedIdentity == nil {
+		return nil, InvalidPolicyFormatError("signedIdentity not specified")
+	}
+	return &prSignedBy{
+		prCommon:       prCommon{Type: prTypeSignedBy},
+		KeyType:        keyType,
+		KeyPath:        keyPath,
+		KeyData:        keyData,
+		SignedIdentity: signedIdentity,
+	}, nil
+}
+
+// newPRSignedByKeyPath is NewPRSignedByKeyPath, except it returns the private type.
+func newPRSignedByKeyPath(keyType sbKeyType, keyPath string, signedIdentity PolicyReferenceMatch) (*prSignedBy, error) {
+	return newPRSignedBy(keyType, keyPath, nil, signedIdentity)
+}
+
+// NewPRSignedByKeyPath returns a new "signedBy" PolicyRequirement using a KeyPath
+func NewPRSignedByKeyPath(keyType sbKeyType, keyPath string, signedIdentity PolicyReferenceMatch) (PolicyRequirement, error) {
+	return newPRSignedByKeyPath(keyType, keyPath, signedIdentity)
+}
+
+// newPRSignedByKeyData is NewPRSignedByKeyData, except it returns the private type.
+func newPRSignedByKeyData(keyType sbKeyType, keyData []byte, signedIdentity PolicyReferenceMatch) (*prSignedBy, error) {
+	return newPRSignedBy(keyType, "", keyData, signedIdentity)
+}
+
+// NewPRSignedByKeyData returns a new "signedBy" PolicyRequirement using a KeyData
+func NewPRSignedByKeyData(keyType sbKeyType, keyData []byte, signedIdentity PolicyReferenceMatch) (PolicyRequirement, error) {
+	return newPRSignedByKeyData(keyType, keyData, signedIdentity)
+}
+
+// Compile-time check that prSignedBy implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prSignedBy)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (pr *prSignedBy) UnmarshalJSON(data []byte) error {
+	*pr = prSignedBy{}
+	var tmp prSignedBy
+	var gotKeyPath, gotKeyData = false, false
+	var signedIdentity json.RawMessage
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		case "keyType":
+			return &tmp.KeyType
+		case "keyPath":
+			gotKeyPath = true
+			return &tmp.KeyPath
+		case "keyData":
+			gotKeyData = true
+			return &tmp.KeyData
+		case "signedIdentity":
+			return &signedIdentity
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prTypeSignedBy {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+	if signedIdentity == nil {
+		tmp.SignedIdentity = NewPRMMatchRepoDigestOrExact()
+	} else {
+		si, err := newPolicyReferenceMatchFromJSON(signedIdentity)
+		if err != nil {
+			return err
+		}
+		tmp.SignedIdentity = si
+	}
+
+	var res *prSignedBy
+	var err error
+	switch {
+	case gotKeyPath && gotKeyData:
+		return InvalidPolicyFormatError("keyPath and keyData cannot be used simultaneously")
+	case gotKeyPath && !gotKeyData:
+		res, err = newPRSignedByKeyPath(tmp.KeyType, tmp.KeyPath, tmp.SignedIdentity)
+	case !gotKeyPath && gotKeyData:
+		res, err = newPRSignedByKeyData(tmp.KeyType, tmp.KeyData, tmp.SignedIdentity)
+	case !gotKeyPath && !gotKeyData:
+		return InvalidPolicyFormatError("At least one of keyPath and keyData mus be specified")
+	default: // Coverage: This should never happen
+		return fmt.Errorf("Impossible keyPath/keyData presence combination!?")
+	}
+	if err != nil {
+		return err
+	}
+	*pr = *res
+
+	return nil
+}
+
+// IsValid returns true iff kt is a recognized value
+func (kt sbKeyType) IsValid() bool {
+	switch kt {
+	case SBKeyTypeGPGKeys, SBKeyTypeSignedByGPGKeys,
+		SBKeyTypeX509Certificates, SBKeyTypeSignedByX509CAs:
+		return true
+	default:
+		return false
+	}
+}
+
+// Compile-time check that sbKeyType implements json.Unmarshaler.
+var _ json.Unmarshaler = (*sbKeyType)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (kt *sbKeyType) UnmarshalJSON(data []byte) error {
+	*kt = sbKeyType("")
+	var s string
+	if err := json.Unmarshal(data, &s); err != nil {
+		return err
+	}
+	if !sbKeyType(s).IsValid() {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unrecognized keyType value \"%s\"", s))
+	}
+	*kt = sbKeyType(s)
+	return nil
+}
+
+// newPRSignedBaseLayer is NewPRSignedBaseLayer, except it returns the private type.
+func newPRSignedBaseLayer(baseLayerIdentity PolicyReferenceMatch) (*prSignedBaseLayer, error) {
+	if baseLayerIdentity == nil {
+		return nil, InvalidPolicyFormatError("baseLayerIdentity not specified")
+	}
+	return &prSignedBaseLayer{
+		prCommon:          prCommon{Type: prTypeSignedBaseLayer},
+		BaseLayerIdentity: baseLayerIdentity,
+	}, nil
+}
+
+// NewPRSignedBaseLayer returns a new "signedBaseLayer" PolicyRequirement.
+func NewPRSignedBaseLayer(baseLayerIdentity PolicyReferenceMatch) (PolicyRequirement, error) {
+	return newPRSignedBaseLayer(baseLayerIdentity)
+}
+
+// Compile-time check that prSignedBaseLayer implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prSignedBaseLayer)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (pr *prSignedBaseLayer) UnmarshalJSON(data []byte) error {
+	*pr = prSignedBaseLayer{}
+	var tmp prSignedBaseLayer
+	var baseLayerIdentity json.RawMessage
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		case "baseLayerIdentity":
+			return &baseLayerIdentity
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prTypeSignedBaseLayer {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+	if baseLayerIdentity == nil {
+		return InvalidPolicyFormatError(fmt.Sprintf("baseLayerIdentity not specified"))
+	}
+	bli, err := newPolicyReferenceMatchFromJSON(baseLayerIdentity)
+	if err != nil {
+		return err
+	}
+	res, err := newPRSignedBaseLayer(bli)
+	if err != nil {
+		// Coverage: This should never happen, newPolicyReferenceMatchFromJSON has ensured bli is valid.
+		return err
+	}
+	*pr = *res
+	return nil
+}
+
+// newPolicyReferenceMatchFromJSON parses JSON data into a PolicyReferenceMatch implementation.
+func newPolicyReferenceMatchFromJSON(data []byte) (PolicyReferenceMatch, error) {
+	var typeField prmCommon
+	if err := json.Unmarshal(data, &typeField); err != nil {
+		return nil, err
+	}
+	var res PolicyReferenceMatch
+	switch typeField.Type {
+	case prmTypeMatchExact:
+		res = &prmMatchExact{}
+	case prmTypeMatchRepoDigestOrExact:
+		res = &prmMatchRepoDigestOrExact{}
+	case prmTypeMatchRepository:
+		res = &prmMatchRepository{}
+	case prmTypeExactReference:
+		res = &prmExactReference{}
+	case prmTypeExactRepository:
+		res = &prmExactRepository{}
+	default:
+		return nil, InvalidPolicyFormatError(fmt.Sprintf("Unknown policy reference match type \"%s\"", typeField.Type))
+	}
+	if err := json.Unmarshal(data, &res); err != nil {
+		return nil, err
+	}
+	return res, nil
+}
+
+// newPRMMatchExact is NewPRMMatchExact, except it resturns the private type.
+func newPRMMatchExact() *prmMatchExact {
+	return &prmMatchExact{prmCommon{Type: prmTypeMatchExact}}
+}
+
+// NewPRMMatchExact returns a new "matchExact" PolicyReferenceMatch.
+func NewPRMMatchExact() PolicyReferenceMatch {
+	return newPRMMatchExact()
+}
+
+// Compile-time check that prmMatchExact implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prmMatchExact)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (prm *prmMatchExact) UnmarshalJSON(data []byte) error {
+	*prm = prmMatchExact{}
+	var tmp prmMatchExact
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prmTypeMatchExact {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+	*prm = *newPRMMatchExact()
+	return nil
+}
+
+// newPRMMatchRepoDigestOrExact is NewPRMMatchRepoDigestOrExact, except it resturns the private type.
+func newPRMMatchRepoDigestOrExact() *prmMatchRepoDigestOrExact {
+	return &prmMatchRepoDigestOrExact{prmCommon{Type: prmTypeMatchRepoDigestOrExact}}
+}
+
+// NewPRMMatchRepoDigestOrExact returns a new "matchRepoDigestOrExact" PolicyReferenceMatch.
+func NewPRMMatchRepoDigestOrExact() PolicyReferenceMatch {
+	return newPRMMatchRepoDigestOrExact()
+}
+
+// Compile-time check that prmMatchRepoDigestOrExact implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prmMatchRepoDigestOrExact)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (prm *prmMatchRepoDigestOrExact) UnmarshalJSON(data []byte) error {
+	*prm = prmMatchRepoDigestOrExact{}
+	var tmp prmMatchRepoDigestOrExact
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prmTypeMatchRepoDigestOrExact {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+	*prm = *newPRMMatchRepoDigestOrExact()
+	return nil
+}
+
+// newPRMMatchRepository is NewPRMMatchRepository, except it resturns the private type.
+func newPRMMatchRepository() *prmMatchRepository {
+	return &prmMatchRepository{prmCommon{Type: prmTypeMatchRepository}}
+}
+
+// NewPRMMatchRepository returns a new "matchRepository" PolicyReferenceMatch.
+func NewPRMMatchRepository() PolicyReferenceMatch {
+	return newPRMMatchRepository()
+}
+
+// Compile-time check that prmMatchRepository implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prmMatchRepository)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (prm *prmMatchRepository) UnmarshalJSON(data []byte) error {
+	*prm = prmMatchRepository{}
+	var tmp prmMatchRepository
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prmTypeMatchRepository {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+	*prm = *newPRMMatchRepository()
+	return nil
+}
+
+// newPRMExactReference is NewPRMExactReference, except it resturns the private type.
+func newPRMExactReference(dockerReference string) (*prmExactReference, error) {
+	ref, err := reference.ParseNamed(dockerReference)
+	if err != nil {
+		return nil, InvalidPolicyFormatError(fmt.Sprintf("Invalid format of dockerReference %s: %s", dockerReference, err.Error()))
+	}
+	if reference.IsNameOnly(ref) {
+		return nil, InvalidPolicyFormatError(fmt.Sprintf("dockerReference %s contains neither a tag nor digest", dockerReference))
+	}
+	return &prmExactReference{
+		prmCommon:       prmCommon{Type: prmTypeExactReference},
+		DockerReference: dockerReference,
+	}, nil
+}
+
+// NewPRMExactReference returns a new "exactReference" PolicyReferenceMatch.
+func NewPRMExactReference(dockerReference string) (PolicyReferenceMatch, error) {
+	return newPRMExactReference(dockerReference)
+}
+
+// Compile-time check that prmExactReference implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prmExactReference)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (prm *prmExactReference) UnmarshalJSON(data []byte) error {
+	*prm = prmExactReference{}
+	var tmp prmExactReference
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		case "dockerReference":
+			return &tmp.DockerReference
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prmTypeExactReference {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+
+	res, err := newPRMExactReference(tmp.DockerReference)
+	if err != nil {
+		return err
+	}
+	*prm = *res
+	return nil
+}
+
+// newPRMExactRepository is NewPRMExactRepository, except it resturns the private type.
+func newPRMExactRepository(dockerRepository string) (*prmExactRepository, error) {
+	if _, err := reference.ParseNamed(dockerRepository); err != nil {
+		return nil, InvalidPolicyFormatError(fmt.Sprintf("Invalid format of dockerRepository %s: %s", dockerRepository, err.Error()))
+	}
+	return &prmExactRepository{
+		prmCommon:        prmCommon{Type: prmTypeExactRepository},
+		DockerRepository: dockerRepository,
+	}, nil
+}
+
+// NewPRMExactRepository returns a new "exactRepository" PolicyRepositoryMatch.
+func NewPRMExactRepository(dockerRepository string) (PolicyReferenceMatch, error) {
+	return newPRMExactRepository(dockerRepository)
+}
+
+// Compile-time check that prmExactRepository implements json.Unmarshaler.
+var _ json.Unmarshaler = (*prmExactRepository)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (prm *prmExactRepository) UnmarshalJSON(data []byte) error {
+	*prm = prmExactRepository{}
+	var tmp prmExactRepository
+	if err := paranoidUnmarshalJSONObject(data, func(key string) interface{} {
+		switch key {
+		case "type":
+			return &tmp.Type
+		case "dockerRepository":
+			return &tmp.DockerRepository
+		default:
+			return nil
+		}
+	}); err != nil {
+		return err
+	}
+
+	if tmp.Type != prmTypeExactRepository {
+		return InvalidPolicyFormatError(fmt.Sprintf("Unexpected policy requirement type \"%s\"", tmp.Type))
+	}
+
+	res, err := newPRMExactRepository(tmp.DockerRepository)
+	if err != nil {
+		return err
+	}
+	*prm = *res
+	return nil
+}

vendor/src/github.com/containers/image/signature/policy_eval.go

@@ -0,0 +1,287 @@
+// This defines the top-level policy evaluation API.
+// To the extent possible, the interface of the fuctions provided
+// here is intended to be completely unambiguous, and stable for users
+// to rely on.
+
+package signature
+
+import (
+	"fmt"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/types"
+)
+
+// PolicyRequirementError is an explanatory text for rejecting a signature or an image.
+type PolicyRequirementError string
+
+func (err PolicyRequirementError) Error() string {
+	return string(err)
+}
+
+// signatureAcceptanceResult is the principal value returned by isSignatureAuthorAccepted.
+type signatureAcceptanceResult string
+
+const (
+	sarAccepted signatureAcceptanceResult = "sarAccepted"
+	sarRejected signatureAcceptanceResult = "sarRejected"
+	sarUnknown  signatureAcceptanceResult = "sarUnknown"
+)
+
+// PolicyRequirement is a rule which must be satisfied by at least one of the signatures of an image.
+// The type is public, but its definition is private.
+type PolicyRequirement interface {
+	// FIXME: For speed, we should support creating per-context state (not stored in the PolicyRequirement), to cache
+	// costly initialization like creating temporary GPG home directories and reading files.
+	// Setup() (someState, error)
+	// Then, the operations below would be done on the someState object, not directly on a PolicyRequirement.
+
+	// isSignatureAuthorAccepted, given an image and a signature blob, returns:
+	// - sarAccepted if the signature has been verified against the appropriate public key
+	//   (where "appropriate public key" may depend on the contents of the signature);
+	//   in that case a parsed Signature should be returned.
+	// - sarRejected if the signature has not been verified;
+	//   in that case error must be non-nil, and should be an PolicyRequirementError if evaluation
+	//   succeeded but the result was rejection.
+	// - sarUnknown if if this PolicyRequirement does not deal with signatures.
+	//   NOTE: sarUnknown should not be returned if this PolicyRequirement should make a decision but something failed.
+	//   Returning sarUnknown and a non-nil error value is invalid.
+	// WARNING: This makes the signature contents acceptable for futher processing,
+	// but it does not necessarily mean that the contents of the signature are
+	// consistent with local policy.
+	// For example:
+	// - Do not use a true value to determine whether to run
+	//   a container based on this image; use IsRunningImageAllowed instead.
+	// - Just because a signature is accepted does not automatically mean the contents of the
+	//   signature are authorized to run code as root, or to affect system or cluster configuration.
+	isSignatureAuthorAccepted(image types.UnparsedImage, sig []byte) (signatureAcceptanceResult, *Signature, error)
+
+	// isRunningImageAllowed returns true if the requirement allows running an image.
+	// If it returns false, err must be non-nil, and should be an PolicyRequirementError if evaluation
+	// succeeded but the result was rejection.
+	// WARNING: This validates signatures and the manifest, but does not download or validate the
+	// layers. Users must validate that the layers match their expected digests.
+	isRunningImageAllowed(image types.UnparsedImage) (bool, error)
+}
+
+// PolicyReferenceMatch specifies a set of image identities accepted in PolicyRequirement.
+// The type is public, but its implementation is private.
+type PolicyReferenceMatch interface {
+	// matchesDockerReference decides whether a specific image identity is accepted for an image
+	// (or, usually, for the image's Reference().DockerReference()).  Note that
+	// image.Reference().DockerReference() may be nil.
+	matchesDockerReference(image types.UnparsedImage, signatureDockerReference string) bool
+}
+
+// PolicyContext encapsulates a policy and possible cached state
+// for speeding up its evaluation.
+type PolicyContext struct {
+	Policy *Policy
+	state  policyContextState // Internal consistency checking
+}
+
+// policyContextState is used internally to verify the users are not misusing a PolicyContext.
+type policyContextState string
+
+const (
+	pcInvalid      policyContextState = ""
+	pcInitializing policyContextState = "Initializing"
+	pcReady        policyContextState = "Ready"
+	pcInUse        policyContextState = "InUse"
+	pcDestroying   policyContextState = "Destroying"
+	pcDestroyed    policyContextState = "Destroyed"
+)
+
+// changeContextState changes pc.state, or fails if the state is unexpected
+func (pc *PolicyContext) changeState(expected, new policyContextState) error {
+	if pc.state != expected {
+		return fmt.Errorf(`"Invalid PolicyContext state, expected "%s", found "%s"`, expected, pc.state)
+	}
+	pc.state = new
+	return nil
+}
+
+// NewPolicyContext sets up and initializes a context for the specified policy.
+// The policy must not be modified while the context exists. FIXME: make a deep copy?
+// If this function succeeds, the caller should call PolicyContext.Destroy() when done.
+func NewPolicyContext(policy *Policy) (*PolicyContext, error) {
+	pc := &PolicyContext{Policy: policy, state: pcInitializing}
+	// FIXME: initialize
+	if err := pc.changeState(pcInitializing, pcReady); err != nil {
+		// Huh?! This should never fail, we didn't give the pointer to anybody.
+		// Just give up and leave unclean state around.
+		return nil, err
+	}
+	return pc, nil
+}
+
+// Destroy should be called when the user of the context is done with it.
+func (pc *PolicyContext) Destroy() error {
+	if err := pc.changeState(pcReady, pcDestroying); err != nil {
+		return err
+	}
+	// FIXME: destroy
+	return pc.changeState(pcDestroying, pcDestroyed)
+}
+
+// policyIdentityLogName returns a string description of the image identity for policy purposes.
+// ONLY use this for log messages, not for any decisions!
+func policyIdentityLogName(ref types.ImageReference) string {
+	return ref.Transport().Name() + ":" + ref.PolicyConfigurationIdentity()
+}
+
+// requirementsForImageRef selects the appropriate requirements for ref.
+func (pc *PolicyContext) requirementsForImageRef(ref types.ImageReference) PolicyRequirements {
+	// Do we have a PolicyTransportScopes for this transport?
+	transportName := ref.Transport().Name()
+	if transportScopes, ok := pc.Policy.Transports[transportName]; ok {
+		// Look for a full match.
+		identity := ref.PolicyConfigurationIdentity()
+		if req, ok := transportScopes[identity]; ok {
+			logrus.Debugf(` Using transport "%s" policy section %s`, transportName, identity)
+			return req
+		}
+
+		// Look for a match of the possible parent namespaces.
+		for _, name := range ref.PolicyConfigurationNamespaces() {
+			if req, ok := transportScopes[name]; ok {
+				logrus.Debugf(` Using transport "%s" specific policy section %s`, transportName, name)
+				return req
+			}
+		}
+
+		// Look for a default match for the transport.
+		if req, ok := transportScopes[""]; ok {
+			logrus.Debugf(` Using transport "%s" policy section ""`, transportName)
+			return req
+		}
+	}
+
+	logrus.Debugf(" Using default policy section")
+	return pc.Policy.Default
+}
+
+// GetSignaturesWithAcceptedAuthor returns those signatures from an image
+// for which the policy accepts the author (and which have been successfully
+// verified).
+// NOTE: This may legitimately return an empty list and no error, if the image
+// has no signatures or only invalid signatures.
+// WARNING: This makes the signature contents acceptable for futher processing,
+// but it does not necessarily mean that the contents of the signature are
+// consistent with local policy.
+// For example:
+// - Do not use a an existence of an accepted signature to determine whether to run
+//   a container based on this image; use IsRunningImageAllowed instead.
+// - Just because a signature is accepted does not automatically mean the contents of the
+//   signature are authorized to run code as root, or to affect system or cluster configuration.
+func (pc *PolicyContext) GetSignaturesWithAcceptedAuthor(image types.UnparsedImage) (sigs []*Signature, finalErr error) {
+	if err := pc.changeState(pcReady, pcInUse); err != nil {
+		return nil, err
+	}
+	defer func() {
+		if err := pc.changeState(pcInUse, pcReady); err != nil {
+			sigs = nil
+			finalErr = err
+		}
+	}()
+
+	logrus.Debugf("GetSignaturesWithAcceptedAuthor for image %s", policyIdentityLogName(image.Reference()))
+	reqs := pc.requirementsForImageRef(image.Reference())
+
+	// FIXME: rename Signatures to UnverifiedSignatures
+	unverifiedSignatures, err := image.Signatures()
+	if err != nil {
+		return nil, err
+	}
+
+	res := make([]*Signature, 0, len(unverifiedSignatures))
+	for sigNumber, sig := range unverifiedSignatures {
+		var acceptedSig *Signature // non-nil if accepted
+		rejected := false
+		// FIXME? Say more about the contents of the signature, i.e. parse it even before verification?!
+		logrus.Debugf("Evaluating signature %d:", sigNumber)
+	interpretingReqs:
+		for reqNumber, req := range reqs {
+			// FIXME: Log the requirement itself? For now, we use just the number.
+			// FIXME: supply state
+			switch res, as, err := req.isSignatureAuthorAccepted(image, sig); res {
+			case sarAccepted:
+				if as == nil { // Coverage: this should never happen
+					logrus.Debugf(" Requirement %d: internal inconsistency: sarAccepted but no parsed contents", reqNumber)
+					rejected = true
+					break interpretingReqs
+				}
+				logrus.Debugf(" Requirement %d: signature accepted", reqNumber)
+				if acceptedSig == nil {
+					acceptedSig = as
+				} else if *as != *acceptedSig { // Coverage: this should never happen
+					// Huh?! Two ways of verifying the same signature blob resulted in two different parses of its already accepted contents?
+					logrus.Debugf(" Requirement %d: internal inconsistency: sarAccepted but different parsed contents", reqNumber)
+					rejected = true
+					acceptedSig = nil
+					break interpretingReqs
+				}
+			case sarRejected:
+				logrus.Debugf(" Requirement %d: signature rejected: %s", reqNumber, err.Error())
+				rejected = true
+				break interpretingReqs
+			case sarUnknown:
+				if err != nil { // Coverage: this should never happen
+					logrus.Debugf(" Requirement %d: internal inconsistency: sarUnknown but an error message %s", reqNumber, err.Error())
+					rejected = true
+					break interpretingReqs
+				}
+				logrus.Debugf(" Requirement %d: signature state unknown, continuing", reqNumber)
+			default: // Coverage: this should never happen
+				logrus.Debugf(" Requirement %d: internal inconsistency: unknown result %#v", reqNumber, string(res))
+				rejected = true
+				break interpretingReqs
+			}
+		}
+		// This also handles the (invalid) case of empty reqs, by rejecting the signature.
+		if acceptedSig != nil && !rejected {
+			logrus.Debugf(" Overall: OK, signature accepted")
+			res = append(res, acceptedSig)
+		} else {
+			logrus.Debugf(" Overall: Signature not accepted")
+		}
+	}
+	return res, nil
+}
+
+// IsRunningImageAllowed returns true iff the policy allows running the image.
+// If it returns false, err must be non-nil, and should be an PolicyRequirementError if evaluation
+// succeeded but the result was rejection.
+// WARNING: This validates signatures and the manifest, but does not download or validate the
+// layers. Users must validate that the layers match their expected digests.
+func (pc *PolicyContext) IsRunningImageAllowed(image types.UnparsedImage) (res bool, finalErr error) {
+	if err := pc.changeState(pcReady, pcInUse); err != nil {
+		return false, err
+	}
+	defer func() {
+		if err := pc.changeState(pcInUse, pcReady); err != nil {
+			res = false
+			finalErr = err
+		}
+	}()
+
+	logrus.Debugf("IsRunningImageAllowed for image %s", policyIdentityLogName(image.Reference()))
+	reqs := pc.requirementsForImageRef(image.Reference())
+
+	if len(reqs) == 0 {
+		return false, PolicyRequirementError("List of verification policy requirements must not be empty")
+	}
+
+	for reqNumber, req := range reqs {
+		// FIXME: supply state
+		allowed, err := req.isRunningImageAllowed(image)
+		if !allowed {
+			logrus.Debugf("Requirement %d: denied, done", reqNumber)
+			return false, err
+		}
+		logrus.Debugf(" Requirement %d: allowed", reqNumber)
+	}
+	// We have tested that len(reqs) != 0, so at least one req must have explicitly allowed this image.
+	logrus.Debugf("Overall: allowed")
+	return true, nil
+}

vendor/src/github.com/containers/image/signature/policy_eval_baselayer.go

@@ -0,0 +1,18 @@
+// Policy evaluation for prSignedBaseLayer.
+
+package signature
+
+import (
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/types"
+)
+
+func (pr *prSignedBaseLayer) isSignatureAuthorAccepted(image types.UnparsedImage, sig []byte) (signatureAcceptanceResult, *Signature, error) {
+	return sarUnknown, nil, nil
+}
+
+func (pr *prSignedBaseLayer) isRunningImageAllowed(image types.UnparsedImage) (bool, error) {
+	// FIXME? Reject this at policy parsing time already?
+	logrus.Errorf("signedBaseLayer not implemented yet!")
+	return false, PolicyRequirementError("signedBaseLayer not implemented yet!")
+}

vendor/src/github.com/containers/image/signature/policy_eval_signedby.go

@@ -0,0 +1,138 @@
+// Policy evaluation for prSignedBy.
+
+package signature
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
+
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/digest"
+)
+
+func (pr *prSignedBy) isSignatureAuthorAccepted(image types.UnparsedImage, sig []byte) (signatureAcceptanceResult, *Signature, error) {
+	switch pr.KeyType {
+	case SBKeyTypeGPGKeys:
+	case SBKeyTypeSignedByGPGKeys, SBKeyTypeX509Certificates, SBKeyTypeSignedByX509CAs:
+		// FIXME? Reject this at policy parsing time already?
+		return sarRejected, nil, fmt.Errorf(`"Unimplemented "keyType" value "%s"`, string(pr.KeyType))
+	default:
+		// This should never happen, newPRSignedBy ensures KeyType.IsValid()
+		return sarRejected, nil, fmt.Errorf(`"Unknown "keyType" value "%s"`, string(pr.KeyType))
+	}
+
+	if pr.KeyPath != "" && pr.KeyData != nil {
+		return sarRejected, nil, errors.New(`Internal inconsistency: both "keyPath" and "keyData" specified`)
+	}
+	// FIXME: move this to per-context initialization
+	var data []byte
+	if pr.KeyData != nil {
+		data = pr.KeyData
+	} else {
+		d, err := ioutil.ReadFile(pr.KeyPath)
+		if err != nil {
+			return sarRejected, nil, err
+		}
+		data = d
+	}
+
+	// FIXME: move this to per-context initialization
+	dir, err := ioutil.TempDir("", "skopeo-signedBy-")
+	if err != nil {
+		return sarRejected, nil, err
+	}
+	defer os.RemoveAll(dir)
+	mech, err := newGPGSigningMechanismInDirectory(dir)
+	if err != nil {
+		return sarRejected, nil, err
+	}
+
+	trustedIdentities, err := mech.ImportKeysFromBytes(data)
+	if err != nil {
+		return sarRejected, nil, err
+	}
+	if len(trustedIdentities) == 0 {
+		return sarRejected, nil, PolicyRequirementError("No public keys imported")
+	}
+
+	signature, err := verifyAndExtractSignature(mech, sig, signatureAcceptanceRules{
+		validateKeyIdentity: func(keyIdentity string) error {
+			for _, trustedIdentity := range trustedIdentities {
+				if keyIdentity == trustedIdentity {
+					return nil
+				}
+			}
+			// Coverage: We use a private GPG home directory and only import trusted keys, so this should
+			// not be reachable.
+			return PolicyRequirementError(fmt.Sprintf("Signature by key %s is not accepted", keyIdentity))
+		},
+		validateSignedDockerReference: func(ref string) error {
+			if !pr.SignedIdentity.matchesDockerReference(image, ref) {
+				return PolicyRequirementError(fmt.Sprintf("Signature for identity %s is not accepted", ref))
+			}
+			return nil
+		},
+		validateSignedDockerManifestDigest: func(digest digest.Digest) error {
+			m, _, err := image.Manifest()
+			if err != nil {
+				return err
+			}
+			digestMatches, err := manifest.MatchesDigest(m, digest)
+			if err != nil {
+				return err
+			}
+			if !digestMatches {
+				return PolicyRequirementError(fmt.Sprintf("Signature for digest %s does not match", digest))
+			}
+			return nil
+		},
+	})
+	if err != nil {
+		return sarRejected, nil, err
+	}
+
+	return sarAccepted, signature, nil
+}
+
+func (pr *prSignedBy) isRunningImageAllowed(image types.UnparsedImage) (bool, error) {
+	sigs, err := image.Signatures()
+	if err != nil {
+		return false, err
+	}
+	var rejections []error
+	for _, s := range sigs {
+		var reason error
+		switch res, _, err := pr.isSignatureAuthorAccepted(image, s); res {
+		case sarAccepted:
+			// One accepted signature is enough.
+			return true, nil
+		case sarRejected:
+			reason = err
+		case sarUnknown:
+			// Huh?! This should not happen at all; treat it as any other invalid value.
+			fallthrough
+		default:
+			reason = fmt.Errorf(`Internal error: Unexpected signature verification result "%s"`, string(res))
+		}
+		rejections = append(rejections, reason)
+	}
+	var summary error
+	switch len(rejections) {
+	case 0:
+		summary = PolicyRequirementError("A signature was required, but no signature exists")
+	case 1:
+		summary = rejections[0]
+	default:
+		var msgs []string
+		for _, e := range rejections {
+			msgs = append(msgs, e.Error())
+		}
+		summary = PolicyRequirementError(fmt.Sprintf("None of the signatures were accepted, reasons: %s",
+			strings.Join(msgs, "; ")))
+	}
+	return false, summary
+}

vendor/src/github.com/containers/image/signature/policy_eval_simple.go

@@ -0,0 +1,28 @@
+// Policy evaluation for the various simple PolicyRequirement types.
+
+package signature
+
+import (
+	"fmt"
+
+	"github.com/containers/image/transports"
+	"github.com/containers/image/types"
+)
+
+func (pr *prInsecureAcceptAnything) isSignatureAuthorAccepted(image types.UnparsedImage, sig []byte) (signatureAcceptanceResult, *Signature, error) {
+	// prInsecureAcceptAnything semantics: Every image is allowed to run,
+	// but this does not consider the signature as verified.
+	return sarUnknown, nil, nil
+}
+
+func (pr *prInsecureAcceptAnything) isRunningImageAllowed(image types.UnparsedImage) (bool, error) {
+	return true, nil
+}
+
+func (pr *prReject) isSignatureAuthorAccepted(image types.UnparsedImage, sig []byte) (signatureAcceptanceResult, *Signature, error) {
+	return sarRejected, nil, PolicyRequirementError(fmt.Sprintf("Any signatures for image %s are rejected by policy.", transports.ImageName(image.Reference())))
+}
+
+func (pr *prReject) isRunningImageAllowed(image types.UnparsedImage) (bool, error) {
+	return false, PolicyRequirementError(fmt.Sprintf("Running image %s is rejected by policy.", transports.ImageName(image.Reference())))
+}

vendor/src/github.com/containers/image/signature/policy_reference_match.go

@@ -0,0 +1,101 @@
+// PolicyReferenceMatch implementations.
+
+package signature
+
+import (
+	"fmt"
+
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/transports"
+	"github.com/containers/image/types"
+)
+
+// parseImageAndDockerReference converts an image and a reference string into two parsed entities, failing on any error and handling unidentified images.
+func parseImageAndDockerReference(image types.UnparsedImage, s2 string) (reference.Named, reference.Named, error) {
+	r1 := image.Reference().DockerReference()
+	if r1 == nil {
+		return nil, nil, PolicyRequirementError(fmt.Sprintf("Docker reference match attempted on image %s with no known Docker reference identity",
+			transports.ImageName(image.Reference())))
+	}
+	r2, err := reference.ParseNamed(s2)
+	if err != nil {
+		return nil, nil, err
+	}
+	return r1, r2, nil
+}
+
+func (prm *prmMatchExact) matchesDockerReference(image types.UnparsedImage, signatureDockerReference string) bool {
+	intended, signature, err := parseImageAndDockerReference(image, signatureDockerReference)
+	if err != nil {
+		return false
+	}
+	// Do not add default tags: image.Reference().DockerReference() should contain it already, and signatureDockerReference should be exact; so, verify that now.
+	if reference.IsNameOnly(intended) || reference.IsNameOnly(signature) {
+		return false
+	}
+	return signature.String() == intended.String()
+}
+
+func (prm *prmMatchRepoDigestOrExact) matchesDockerReference(image types.UnparsedImage, signatureDockerReference string) bool {
+	intended, signature, err := parseImageAndDockerReference(image, signatureDockerReference)
+	if err != nil {
+		return false
+	}
+
+	// Do not add default tags: image.Reference().DockerReference() should contain it already, and signatureDockerReference should be exact; so, verify that now.
+	if reference.IsNameOnly(signature) {
+		return false
+	}
+	switch intended.(type) {
+	case reference.NamedTagged: // Includes the case when intended has both a tag and a digest.
+		return signature.String() == intended.String()
+	case reference.Canonical:
+		// We don’t actually compare the manifest digest against the signature here; that happens prSignedBy.in UnparsedImage.Manifest.
+		// Becase UnparsedImage.Manifest verifies the intended.Digest() against the manifest, and prSignedBy verifies the signature digest against the manifest,
+		// we know that signature digest matches intended.Digest() (but intended.Digest() and signature digest may use different algorithms)
+		return signature.Name() == intended.Name()
+	default: // !reference.IsNameOnly(intended)
+		return false
+	}
+}
+
+func (prm *prmMatchRepository) matchesDockerReference(image types.UnparsedImage, signatureDockerReference string) bool {
+	intended, signature, err := parseImageAndDockerReference(image, signatureDockerReference)
+	if err != nil {
+		return false
+	}
+	return signature.Name() == intended.Name()
+}
+
+// parseDockerReferences converts two reference strings into parsed entities, failing on any error
+func parseDockerReferences(s1, s2 string) (reference.Named, reference.Named, error) {
+	r1, err := reference.ParseNamed(s1)
+	if err != nil {
+		return nil, nil, err
+	}
+	r2, err := reference.ParseNamed(s2)
+	if err != nil {
+		return nil, nil, err
+	}
+	return r1, r2, nil
+}
+
+func (prm *prmExactReference) matchesDockerReference(image types.UnparsedImage, signatureDockerReference string) bool {
+	intended, signature, err := parseDockerReferences(prm.DockerReference, signatureDockerReference)
+	if err != nil {
+		return false
+	}
+	// prm.DockerReference and signatureDockerReference should be exact; so, verify that now.
+	if reference.IsNameOnly(intended) || reference.IsNameOnly(signature) {
+		return false
+	}
+	return signature.String() == intended.String()
+}
+
+func (prm *prmExactRepository) matchesDockerReference(image types.UnparsedImage, signatureDockerReference string) bool {
+	intended, signature, err := parseDockerReferences(prm.DockerRepository, signatureDockerReference)
+	if err != nil {
+		return false
+	}
+	return signature.Name() == intended.Name()
+}

vendor/src/github.com/containers/image/signature/policy_types.go

@@ -0,0 +1,152 @@
+// Note: Consider the API unstable until the code supports at least three different image formats or transports.
+
+// This defines types used to represent a signature verification policy in memory.
+// Do not use the private types directly; either parse a configuration file, or construct a Policy from PolicyRequirements
+// built using the constructor functions provided in policy_config.go.
+
+package signature
+
+// NOTE: Keep this in sync with docs/policy.json.md!
+
+// Policy defines requirements for considering a signature, or an image, valid.
+type Policy struct {
+	// Default applies to any image which does not have a matching policy in Transports.
+	// Note that this can happen even if a matching PolicyTransportScopes exists in Transports
+	// if the image matches none of the scopes.
+	Default    PolicyRequirements               `json:"default"`
+	Transports map[string]PolicyTransportScopes `json:"transports"`
+}
+
+// PolicyTransportScopes defines policies for images for a specific transport,
+// for various scopes, the map keys.
+// Scopes are defined by the transport (types.ImageReference.PolicyConfigurationIdentity etc.);
+// there is one scope precisely matching to a single image, and namespace scopes as prefixes
+// of the single-image scope. (e.g. hostname[/zero[/or[/more[/namespaces[/individualimage]]]]])
+// The empty scope, if exists, is considered a parent namespace of all other scopes.
+// Most specific scope wins, duplication is prohibited (hard failure).
+type PolicyTransportScopes map[string]PolicyRequirements
+
+// PolicyRequirements is a set of requirements applying to a set of images; each of them must be satisfied (though perhaps each by a different signature).
+// Must not be empty, frequently will only contain a single element.
+type PolicyRequirements []PolicyRequirement
+
+// PolicyRequirement is a rule which must be satisfied by at least one of the signatures of an image.
+// The type is public, but its definition is private.
+
+// prCommon is the common type field in a JSON encoding of PolicyRequirement.
+type prCommon struct {
+	Type prTypeIdentifier `json:"type"`
+}
+
+// prTypeIdentifier is string designating a kind of a PolicyRequirement.
+type prTypeIdentifier string
+
+const (
+	prTypeInsecureAcceptAnything prTypeIdentifier = "insecureAcceptAnything"
+	prTypeReject                 prTypeIdentifier = "reject"
+	prTypeSignedBy               prTypeIdentifier = "signedBy"
+	prTypeSignedBaseLayer        prTypeIdentifier = "signedBaseLayer"
+)
+
+// prInsecureAcceptAnything is a PolicyRequirement with type = prTypeInsecureAcceptAnything:
+// every image is allowed to run.
+// Note that because PolicyRequirements are implicitly ANDed, this is necessary only if it is the only rule (to make the list non-empty and the policy explicit).
+// NOTE: This allows the image to run; it DOES NOT consider the signature verified (per IsSignatureAuthorAccepted).
+// FIXME? Better name?
+type prInsecureAcceptAnything struct {
+	prCommon
+}
+
+// prReject is a PolicyRequirement with type = prTypeReject: every image is rejected.
+type prReject struct {
+	prCommon
+}
+
+// prSignedBy is a PolicyRequirement with type = prTypeSignedBy: the image is signed by trusted keys for a specified identity
+type prSignedBy struct {
+	prCommon
+
+	// KeyType specifies what kind of key reference KeyPath/KeyData is.
+	// Acceptable values are “GPGKeys” | “signedByGPGKeys” “X.509Certificates” | “signedByX.509CAs”
+	// FIXME: eventually also support GPGTOFU, X.509TOFU, with KeyPath only
+	KeyType sbKeyType `json:"keyType"`
+
+	// KeyPath is a pathname to a local file containing the trusted key(s). Exactly one of KeyPath and KeyData must be specified.
+	KeyPath string `json:"keyPath,omitempty"`
+	// KeyData contains the trusted key(s), base64-encoded. Exactly one of KeyPath and KeyData must be specified.
+	KeyData []byte `json:"keyData,omitempty"`
+
+	// SignedIdentity specifies what image identity the signature must be claiming about the image.
+	// Defaults to "match-exact" if not specified.
+	SignedIdentity PolicyReferenceMatch `json:"signedIdentity"`
+}
+
+// sbKeyType are the allowed values for prSignedBy.KeyType
+type sbKeyType string
+
+const (
+	// SBKeyTypeGPGKeys refers to keys contained in a GPG keyring
+	SBKeyTypeGPGKeys sbKeyType = "GPGKeys"
+	// SBKeyTypeSignedByGPGKeys refers to keys signed by keys in a GPG keyring
+	SBKeyTypeSignedByGPGKeys sbKeyType = "signedByGPGKeys"
+	// SBKeyTypeX509Certificates refers to keys in a set of X.509 certificates
+	// FIXME: PEM, DER?
+	SBKeyTypeX509Certificates sbKeyType = "X509Certificates"
+	// SBKeyTypeSignedByX509CAs refers to keys signed by one of the X.509 CAs
+	// FIXME: PEM, DER?
+	SBKeyTypeSignedByX509CAs sbKeyType = "signedByX509CAs"
+)
+
+// prSignedBaseLayer is a PolicyRequirement with type = prSignedBaseLayer: the image has a specified, correctly signed, base image.
+type prSignedBaseLayer struct {
+	prCommon
+	// BaseLayerIdentity specifies the base image to look for. "match-exact" is rejected, "match-repository" is unlikely to be useful.
+	BaseLayerIdentity PolicyReferenceMatch `json:"baseLayerIdentity"`
+}
+
+// PolicyReferenceMatch specifies a set of image identities accepted in PolicyRequirement.
+// The type is public, but its implementation is private.
+
+// prmCommon is the common type field in a JSON encoding of PolicyReferenceMatch.
+type prmCommon struct {
+	Type prmTypeIdentifier `json:"type"`
+}
+
+// prmTypeIdentifier is string designating a kind of a PolicyReferenceMatch.
+type prmTypeIdentifier string
+
+const (
+	prmTypeMatchExact             prmTypeIdentifier = "matchExact"
+	prmTypeMatchRepoDigestOrExact prmTypeIdentifier = "matchRepoDigestOrExact"
+	prmTypeMatchRepository        prmTypeIdentifier = "matchRepository"
+	prmTypeExactReference         prmTypeIdentifier = "exactReference"
+	prmTypeExactRepository        prmTypeIdentifier = "exactRepository"
+)
+
+// prmMatchExact is a PolicyReferenceMatch with type = prmMatchExact: the two references must match exactly.
+type prmMatchExact struct {
+	prmCommon
+}
+
+// prmMatchRepoDigestOrExact is a PolicyReferenceMatch with type = prmMatchExactOrDigest: the two references must match exactly,
+// except that digest references are also accepted if the repository name matches (regardless of tag/digest) and the signature applies to the referenced digest
+type prmMatchRepoDigestOrExact struct {
+	prmCommon
+}
+
+// prmMatchRepository is a PolicyReferenceMatch with type = prmMatchRepository: the two references must use the same repository, may differ in the tag.
+type prmMatchRepository struct {
+	prmCommon
+}
+
+// prmExactReference is a PolicyReferenceMatch with type = prmExactReference: matches a specified reference exactly.
+type prmExactReference struct {
+	prmCommon
+	DockerReference string `json:"dockerReference"`
+}
+
+// prmExactRepository is a PolicyReferenceMatch with type = prmExactRepository: matches a specified repository, with any tag.
+type prmExactRepository struct {
+	prmCommon
+	DockerRepository string `json:"dockerRepository"`
+}

vendor/src/github.com/containers/image/signature/signature.go

@@ -0,0 +1,192 @@
+// Note: Consider the API unstable until the code supports at least three different image formats or transports.
+
+package signature
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/containers/image/version"
+	"github.com/docker/distribution/digest"
+)
+
+const (
+	signatureType = "atomic container signature"
+)
+
+// InvalidSignatureError is returned when parsing an invalid signature.
+type InvalidSignatureError struct {
+	msg string
+}
+
+func (err InvalidSignatureError) Error() string {
+	return err.msg
+}
+
+// Signature is a parsed content of a signature.
+type Signature struct {
+	DockerManifestDigest digest.Digest
+	DockerReference      string // FIXME: more precise type?
+}
+
+// Wrap signature to add to it some methods which we don't want to make public.
+type privateSignature struct {
+	Signature
+}
+
+// Compile-time check that privateSignature implements json.Marshaler
+var _ json.Marshaler = (*privateSignature)(nil)
+
+// MarshalJSON implements the json.Marshaler interface.
+func (s privateSignature) MarshalJSON() ([]byte, error) {
+	return s.marshalJSONWithVariables(time.Now().UTC().Unix(), "atomic "+version.Version)
+}
+
+// Implementation of MarshalJSON, with a caller-chosen values of the variable items to help testing.
+func (s privateSignature) marshalJSONWithVariables(timestamp int64, creatorID string) ([]byte, error) {
+	if s.DockerManifestDigest == "" || s.DockerReference == "" {
+		return nil, errors.New("Unexpected empty signature content")
+	}
+	critical := map[string]interface{}{
+		"type":     signatureType,
+		"image":    map[string]string{"docker-manifest-digest": s.DockerManifestDigest.String()},
+		"identity": map[string]string{"docker-reference": s.DockerReference},
+	}
+	optional := map[string]interface{}{
+		"creator":   creatorID,
+		"timestamp": timestamp,
+	}
+	signature := map[string]interface{}{
+		"critical": critical,
+		"optional": optional,
+	}
+	return json.Marshal(signature)
+}
+
+// Compile-time check that privateSignature implements json.Unmarshaler
+var _ json.Unmarshaler = (*privateSignature)(nil)
+
+// UnmarshalJSON implements the json.Unmarshaler interface
+func (s *privateSignature) UnmarshalJSON(data []byte) error {
+	err := s.strictUnmarshalJSON(data)
+	if err != nil {
+		if _, ok := err.(jsonFormatError); ok {
+			err = InvalidSignatureError{msg: err.Error()}
+		}
+	}
+	return err
+}
+
+// strictUnmarshalJSON is UnmarshalJSON, except that it may return the internal jsonFormatError error type.
+// Splitting it into a separate function allows us to do the jsonFormatError → InvalidSignatureError in a single place, the caller.
+func (s *privateSignature) strictUnmarshalJSON(data []byte) error {
+	var untyped interface{}
+	if err := json.Unmarshal(data, &untyped); err != nil {
+		return err
+	}
+	o, ok := untyped.(map[string]interface{})
+	if !ok {
+		return InvalidSignatureError{msg: "Invalid signature format"}
+	}
+	if err := validateExactMapKeys(o, "critical", "optional"); err != nil {
+		return err
+	}
+
+	c, err := mapField(o, "critical")
+	if err != nil {
+		return err
+	}
+	if err := validateExactMapKeys(c, "type", "image", "identity"); err != nil {
+		return err
+	}
+
+	optional, err := mapField(o, "optional")
+	if err != nil {
+		return err
+	}
+	_ = optional // We don't use anything from here for now.
+
+	t, err := stringField(c, "type")
+	if err != nil {
+		return err
+	}
+	if t != signatureType {
+		return InvalidSignatureError{msg: fmt.Sprintf("Unrecognized signature type %s", t)}
+	}
+
+	image, err := mapField(c, "image")
+	if err != nil {
+		return err
+	}
+	if err := validateExactMapKeys(image, "docker-manifest-digest"); err != nil {
+		return err
+	}
+	digestString, err := stringField(image, "docker-manifest-digest")
+	if err != nil {
+		return err
+	}
+	s.DockerManifestDigest = digest.Digest(digestString)
+
+	identity, err := mapField(c, "identity")
+	if err != nil {
+		return err
+	}
+	if err := validateExactMapKeys(identity, "docker-reference"); err != nil {
+		return err
+	}
+	reference, err := stringField(identity, "docker-reference")
+	if err != nil {
+		return err
+	}
+	s.DockerReference = reference
+
+	return nil
+}
+
+// Sign formats the signature and returns a blob signed using mech and keyIdentity
+func (s privateSignature) sign(mech SigningMechanism, keyIdentity string) ([]byte, error) {
+	json, err := json.Marshal(s)
+	if err != nil {
+		return nil, err
+	}
+
+	return mech.Sign(json, keyIdentity)
+}
+
+// signatureAcceptanceRules specifies how to decide whether an untrusted signature is acceptable.
+// We centralize the actual parsing and data extraction in verifyAndExtractSignature; this supplies
+// the policy.  We use an object instead of supplying func parameters to verifyAndExtractSignature
+// because all of the functions have the same type, so there is a risk of exchanging the functions;
+// named members of this struct are more explicit.
+type signatureAcceptanceRules struct {
+	validateKeyIdentity                func(string) error
+	validateSignedDockerReference      func(string) error
+	validateSignedDockerManifestDigest func(digest.Digest) error
+}
+
+// verifyAndExtractSignature verifies that unverifiedSignature has been signed, and that its principial components
+// match expected values, both as specified by rules, and returns it
+func verifyAndExtractSignature(mech SigningMechanism, unverifiedSignature []byte, rules signatureAcceptanceRules) (*Signature, error) {
+	signed, keyIdentity, err := mech.Verify(unverifiedSignature)
+	if err != nil {
+		return nil, err
+	}
+	if err := rules.validateKeyIdentity(keyIdentity); err != nil {
+		return nil, err
+	}
+
+	var unmatchedSignature privateSignature
+	if err := json.Unmarshal(signed, &unmatchedSignature); err != nil {
+		return nil, InvalidSignatureError{msg: err.Error()}
+	}
+	if err := rules.validateSignedDockerManifestDigest(unmatchedSignature.DockerManifestDigest); err != nil {
+		return nil, err
+	}
+	if err := rules.validateSignedDockerReference(unmatchedSignature.DockerReference); err != nil {
+		return nil, err
+	}
+	signature := unmatchedSignature.Signature // Policy OK.
+	return &signature, nil
+}

vendor/src/github.com/containers/image/storage/storage_image.go

@@ -0,0 +1,570 @@
+package storage
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"time"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/image"
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/containers/storage/pkg/archive"
+	"github.com/containers/storage/pkg/ioutils"
+	"github.com/containers/storage/storage"
+	ddigest "github.com/docker/distribution/digest"
+)
+
+var (
+	// ErrBlobDigestMismatch is returned when PutBlob() is given a blob
+	// with a digest-based name that doesn't match its contents.
+	ErrBlobDigestMismatch = errors.New("blob digest mismatch")
+	// ErrBlobSizeMismatch is returned when PutBlob() is given a blob
+	// with an expected size that doesn't match the reader.
+	ErrBlobSizeMismatch = errors.New("blob size mismatch")
+	// ErrNoManifestLists is returned when GetTargetManifest() is
+	// called.
+	ErrNoManifestLists = errors.New("manifest lists are not supported by this transport")
+	// ErrNoSuchImage is returned when we attempt to access an image which
+	// doesn't exist in the storage area.
+	ErrNoSuchImage = storage.ErrNotAnImage
+)
+
+type storageImageSource struct {
+	imageRef       storageReference
+	Tag            string                      `json:"tag,omitempty"`
+	Created        time.Time                   `json:"created-time,omitempty"`
+	ID             string                      `json:"id"`
+	BlobList       []types.BlobInfo            `json:"blob-list,omitempty"` // Ordered list of every blob the image has been told to handle
+	Layers         map[ddigest.Digest][]string `json:"layers,omitempty"`    // Map from digests of blobs to lists of layer IDs
+	LayerPosition  map[ddigest.Digest]int      `json:"-"`                   // Where we are in reading a blob's layers
+	SignatureSizes []int                       `json:"signature-sizes"`     // List of sizes of each signature slice
+}
+
+type storageImageDestination struct {
+	imageRef       storageReference
+	Tag            string                      `json:"tag,omitempty"`
+	Created        time.Time                   `json:"created-time,omitempty"`
+	ID             string                      `json:"id"`
+	BlobList       []types.BlobInfo            `json:"blob-list,omitempty"` // Ordered list of every blob the image has been told to handle
+	Layers         map[ddigest.Digest][]string `json:"layers,omitempty"`    // Map from digests of blobs to lists of layer IDs
+	BlobData       map[ddigest.Digest][]byte   `json:"-"`                   // Map from names of blobs that aren't layers to contents, temporary
+	Manifest       []byte                      `json:"-"`                   // Manifest contents, temporary
+	Signatures     []byte                      `json:"-"`                   // Signature contents, temporary
+	SignatureSizes []int                       `json:"signature-sizes"`     // List of sizes of each signature slice
+}
+
+type storageLayerMetadata struct {
+	Digest         string `json:"digest,omitempty"`
+	Size           int64  `json:"size"`
+	CompressedSize int64  `json:"compressed-size,omitempty"`
+}
+
+type storageImage struct {
+	types.Image
+	size int64
+}
+
+// newImageSource sets us up to read out an image, which needs to already exist.
+func newImageSource(imageRef storageReference) (*storageImageSource, error) {
+	id := imageRef.resolveID()
+	if id == "" {
+		logrus.Errorf("no image matching reference %q found", imageRef.StringWithinTransport())
+		return nil, ErrNoSuchImage
+	}
+	img, err := imageRef.transport.store.GetImage(id)
+	if err != nil {
+		return nil, fmt.Errorf("error reading image %q: %v", id, err)
+	}
+	image := &storageImageSource{
+		imageRef:       imageRef,
+		Created:        time.Now(),
+		ID:             img.ID,
+		BlobList:       []types.BlobInfo{},
+		Layers:         make(map[ddigest.Digest][]string),
+		LayerPosition:  make(map[ddigest.Digest]int),
+		SignatureSizes: []int{},
+	}
+	if err := json.Unmarshal([]byte(img.Metadata), image); err != nil {
+		return nil, fmt.Errorf("error decoding metadata for source image: %v", err)
+	}
+	return image, nil
+}
+
+// newImageDestination sets us up to write a new image.
+func newImageDestination(imageRef storageReference) (*storageImageDestination, error) {
+	image := &storageImageDestination{
+		imageRef:       imageRef,
+		Tag:            imageRef.reference,
+		Created:        time.Now(),
+		ID:             imageRef.id,
+		BlobList:       []types.BlobInfo{},
+		Layers:         make(map[ddigest.Digest][]string),
+		BlobData:       make(map[ddigest.Digest][]byte),
+		SignatureSizes: []int{},
+	}
+	return image, nil
+}
+
+func (s storageImageSource) Reference() types.ImageReference {
+	return s.imageRef
+}
+
+func (s storageImageDestination) Reference() types.ImageReference {
+	return s.imageRef
+}
+
+func (s storageImageSource) Close() {
+}
+
+func (s storageImageDestination) Close() {
+}
+
+func (s storageImageDestination) ShouldCompressLayers() bool {
+	// We ultimately have to decompress layers to populate trees on disk,
+	// so callers shouldn't bother compressing them before handing them to
+	// us, if they're not already compressed.
+	return false
+}
+
+// PutBlob is used to both store filesystem layers and binary data that is part
+// of the image.  Filesystem layers are assumed to be imported in order, as
+// that is required by some of the underlying storage drivers.
+func (s *storageImageDestination) PutBlob(stream io.Reader, blobinfo types.BlobInfo) (types.BlobInfo, error) {
+	blobSize := int64(-1)
+	digest := blobinfo.Digest
+	errorBlobInfo := types.BlobInfo{
+		Digest: "",
+		Size:   -1,
+	}
+	// Try to read an initial snippet of the blob.
+	header := make([]byte, 10240)
+	n, err := stream.Read(header)
+	if err != nil && err != io.EOF {
+		return errorBlobInfo, err
+	}
+	// Set up to read the whole blob (the initial snippet, plus the rest)
+	// while digesting it with either the default, or the passed-in digest,
+	// if one was specified.
+	hasher := ddigest.Canonical.New()
+	if digest.Validate() == nil {
+		if a := digest.Algorithm(); a.Available() {
+			hasher = a.New()
+		}
+	}
+	hash := ""
+	counter := ioutils.NewWriteCounter(hasher.Hash())
+	defragmented := io.MultiReader(bytes.NewBuffer(header[:n]), stream)
+	multi := io.TeeReader(defragmented, counter)
+	if (n > 0) && archive.IsArchive(header[:n]) {
+		// It's a filesystem layer.  If it's not the first one in the
+		// image, we assume that the most recently added layer is its
+		// parent.
+		parentLayer := ""
+		for _, blob := range s.BlobList {
+			if layerList, ok := s.Layers[blob.Digest]; ok {
+				parentLayer = layerList[len(layerList)-1]
+			}
+		}
+		// If we have an expected content digest, generate a layer ID
+		// based on the parent's ID and the expected content digest.
+		id := ""
+		if digest.Validate() == nil {
+			id = ddigest.Canonical.FromBytes([]byte(parentLayer + "+" + digest.String())).Hex()
+		}
+		// Attempt to create the identified layer and import its contents.
+		layer, uncompressedSize, err := s.imageRef.transport.store.PutLayer(id, parentLayer, nil, "", true, multi)
+		if err != nil && err != storage.ErrDuplicateID {
+			logrus.Debugf("error importing layer blob %q as %q: %v", blobinfo.Digest, id, err)
+			return errorBlobInfo, err
+		}
+		if err == storage.ErrDuplicateID {
+			// We specified an ID, and there's already a layer with
+			// the same ID.  Drain the input so that we can look at
+			// its length and digest.
+			_, err := io.Copy(ioutil.Discard, multi)
+			if err != nil && err != io.EOF {
+				logrus.Debugf("error digesting layer blob %q: %v", blobinfo.Digest, id, err)
+				return errorBlobInfo, err
+			}
+			hash = hasher.Digest().String()
+		} else {
+			// Applied the layer with the specified ID.  Note the
+			// size info and computed digest.
+			hash = hasher.Digest().String()
+			layerMeta := storageLayerMetadata{
+				Digest:         hash,
+				CompressedSize: counter.Count,
+				Size:           uncompressedSize,
+			}
+			if metadata, err := json.Marshal(&layerMeta); len(metadata) != 0 && err == nil {
+				s.imageRef.transport.store.SetMetadata(layer.ID, string(metadata))
+			}
+			// Hang on to the new layer's ID.
+			id = layer.ID
+		}
+		blobSize = counter.Count
+		// Check if the size looks right.
+		if blobinfo.Size >= 0 && blobSize != blobinfo.Size {
+			logrus.Debugf("blob %q size is %d, not %d, rejecting", blobinfo.Digest, blobSize, blobinfo.Size)
+			if layer != nil {
+				// Something's wrong; delete the newly-created layer.
+				s.imageRef.transport.store.DeleteLayer(layer.ID)
+			}
+			return errorBlobInfo, ErrBlobSizeMismatch
+		}
+		// If the content digest was specified, verify it.
+		if digest.Validate() == nil && digest.String() != hash {
+			logrus.Debugf("blob %q digests to %q, rejecting", blobinfo.Digest, hash)
+			if layer != nil {
+				// Something's wrong; delete the newly-created layer.
+				s.imageRef.transport.store.DeleteLayer(layer.ID)
+			}
+			return errorBlobInfo, ErrBlobDigestMismatch
+		}
+		// If we didn't get a digest, construct one.
+		if digest == "" {
+			digest = ddigest.Digest(hash)
+		}
+		// Record that this layer blob is a layer, and the layer ID it
+		// ended up having.  This is a list, in case the same blob is
+		// being applied more than once.
+		s.Layers[digest] = append(s.Layers[digest], id)
+		s.BlobList = append(s.BlobList, types.BlobInfo{Digest: digest, Size: blobSize})
+		if layer != nil {
+			logrus.Debugf("blob %q imported as a filesystem layer %q", blobinfo.Digest, id)
+		} else {
+			logrus.Debugf("layer blob %q already present as layer %q", blobinfo.Digest, id)
+		}
+	} else {
+		// It's just data.  Finish scanning it in, check that our
+		// computed digest matches the passed-in digest, and store it,
+		// but leave it out of the blob-to-layer-ID map so that we can
+		// tell that it's not a layer.
+		blob, err := ioutil.ReadAll(multi)
+		if err != nil && err != io.EOF {
+			return errorBlobInfo, err
+		}
+		blobSize = int64(len(blob))
+		hash = hasher.Digest().String()
+		if blobinfo.Size >= 0 && blobSize != blobinfo.Size {
+			logrus.Debugf("blob %q size is %d, not %d, rejecting", blobinfo.Digest, blobSize, blobinfo.Size)
+			return errorBlobInfo, ErrBlobSizeMismatch
+		}
+		// If we were given a digest, verify that the content matches
+		// it.
+		if digest.Validate() == nil && digest.String() != hash {
+			logrus.Debugf("blob %q digests to %q, rejecting", blobinfo.Digest, hash)
+			return errorBlobInfo, ErrBlobDigestMismatch
+		}
+		// If we didn't get a digest, construct one.
+		if digest == "" {
+			digest = ddigest.Digest(hash)
+		}
+		// Save the blob for when we Commit().
+		s.BlobData[digest] = blob
+		s.BlobList = append(s.BlobList, types.BlobInfo{Digest: digest, Size: blobSize})
+		logrus.Debugf("blob %q imported as opaque data %q", blobinfo.Digest, digest)
+	}
+	return types.BlobInfo{
+		Digest: digest,
+		Size:   blobSize,
+	}, nil
+}
+
+func (s *storageImageDestination) HasBlob(blobinfo types.BlobInfo) (bool, int64, error) {
+	if blobinfo.Digest == "" {
+		return false, -1, fmt.Errorf(`"Can not check for a blob with unknown digest`)
+	}
+	for _, blob := range s.BlobList {
+		if blob.Digest == blobinfo.Digest {
+			return true, blob.Size, nil
+		}
+	}
+	return false, -1, types.ErrBlobNotFound
+}
+
+func (s *storageImageDestination) ReapplyBlob(blobinfo types.BlobInfo) (types.BlobInfo, error) {
+	err := blobinfo.Digest.Validate()
+	if err != nil {
+		return types.BlobInfo{}, err
+	}
+	if layerList, ok := s.Layers[blobinfo.Digest]; !ok || len(layerList) < 1 {
+		b, err := s.imageRef.transport.store.GetImageBigData(s.ID, blobinfo.Digest.String())
+		if err != nil {
+			return types.BlobInfo{}, err
+		}
+		return types.BlobInfo{Digest: blobinfo.Digest, Size: int64(len(b))}, nil
+	}
+	layerList := s.Layers[blobinfo.Digest]
+	rc, _, err := diffLayer(s.imageRef.transport.store, layerList[len(layerList)-1])
+	if err != nil {
+		return types.BlobInfo{}, err
+	}
+	return s.PutBlob(rc, blobinfo)
+}
+
+func (s *storageImageDestination) Commit() error {
+	// Create the image record.
+	lastLayer := ""
+	for _, blob := range s.BlobList {
+		if layerList, ok := s.Layers[blob.Digest]; ok {
+			lastLayer = layerList[len(layerList)-1]
+		}
+	}
+	img, err := s.imageRef.transport.store.CreateImage(s.ID, nil, lastLayer, "", nil)
+	if err != nil {
+		logrus.Debugf("error creating image: %q", err)
+		return err
+	}
+	logrus.Debugf("created new image ID %q", img.ID)
+	s.ID = img.ID
+	if s.Tag != "" {
+		// We have a name to set, so move the name to this image.
+		if err := s.imageRef.transport.store.SetNames(img.ID, []string{s.Tag}); err != nil {
+			if _, err2 := s.imageRef.transport.store.DeleteImage(img.ID, true); err2 != nil {
+				logrus.Debugf("error deleting incomplete image %q: %v", img.ID, err2)
+			}
+			logrus.Debugf("error setting names on image %q: %v", img.ID, err)
+			return err
+		}
+		logrus.Debugf("set name of image %q to %q", img.ID, s.Tag)
+	}
+	// Save the data blobs to disk, and drop their contents from memory.
+	keys := []ddigest.Digest{}
+	for k, v := range s.BlobData {
+		if err := s.imageRef.transport.store.SetImageBigData(img.ID, k.String(), v); err != nil {
+			if _, err2 := s.imageRef.transport.store.DeleteImage(img.ID, true); err2 != nil {
+				logrus.Debugf("error deleting incomplete image %q: %v", img.ID, err2)
+			}
+			logrus.Debugf("error saving big data %q for image %q: %v", k, img.ID, err)
+			return err
+		}
+		keys = append(keys, k)
+	}
+	for _, key := range keys {
+		delete(s.BlobData, key)
+	}
+	// Save the manifest, if we have one.
+	if err := s.imageRef.transport.store.SetImageBigData(s.ID, "manifest", s.Manifest); err != nil {
+		if _, err2 := s.imageRef.transport.store.DeleteImage(img.ID, true); err2 != nil {
+			logrus.Debugf("error deleting incomplete image %q: %v", img.ID, err2)
+		}
+		logrus.Debugf("error saving manifest for image %q: %v", img.ID, err)
+		return err
+	}
+	// Save the signatures, if we have any.
+	if err := s.imageRef.transport.store.SetImageBigData(s.ID, "signatures", s.Signatures); err != nil {
+		if _, err2 := s.imageRef.transport.store.DeleteImage(img.ID, true); err2 != nil {
+			logrus.Debugf("error deleting incomplete image %q: %v", img.ID, err2)
+		}
+		logrus.Debugf("error saving signatures for image %q: %v", img.ID, err)
+		return err
+	}
+	// Save our metadata.
+	metadata, err := json.Marshal(s)
+	if err != nil {
+		if _, err2 := s.imageRef.transport.store.DeleteImage(img.ID, true); err2 != nil {
+			logrus.Debugf("error deleting incomplete image %q: %v", img.ID, err2)
+		}
+		logrus.Debugf("error encoding metadata for image %q: %v", img.ID, err)
+		return err
+	}
+	if len(metadata) != 0 {
+		if err = s.imageRef.transport.store.SetMetadata(s.ID, string(metadata)); err != nil {
+			if _, err2 := s.imageRef.transport.store.DeleteImage(img.ID, true); err2 != nil {
+				logrus.Debugf("error deleting incomplete image %q: %v", img.ID, err2)
+			}
+			logrus.Debugf("error saving metadata for image %q: %v", img.ID, err)
+			return err
+		}
+		logrus.Debugf("saved image metadata %q", string(metadata))
+	}
+	return nil
+}
+
+func (s *storageImageDestination) SupportedManifestMIMETypes() []string {
+	return nil
+}
+
+func (s *storageImageDestination) PutManifest(manifest []byte) error {
+	s.Manifest = make([]byte, len(manifest))
+	copy(s.Manifest, manifest)
+	return nil
+}
+
+// SupportsSignatures returns an error if we can't expect GetSignatures() to
+// return data that was previously supplied to PutSignatures().
+func (s *storageImageDestination) SupportsSignatures() error {
+	return nil
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (s *storageImageDestination) AcceptsForeignLayerURLs() bool {
+	return false
+}
+
+func (s *storageImageDestination) PutSignatures(signatures [][]byte) error {
+	sizes := []int{}
+	sigblob := []byte{}
+	for _, sig := range signatures {
+		sizes = append(sizes, len(sig))
+		newblob := make([]byte, len(sigblob)+len(sig))
+		copy(newblob, sigblob)
+		copy(newblob[len(sigblob):], sig)
+		sigblob = newblob
+	}
+	s.Signatures = sigblob
+	s.SignatureSizes = sizes
+	return nil
+}
+
+func (s *storageImageSource) GetBlob(info types.BlobInfo) (rc io.ReadCloser, n int64, err error) {
+	rc, n, _, err = s.getBlobAndLayerID(info)
+	return rc, n, err
+}
+
+func (s *storageImageSource) getBlobAndLayerID(info types.BlobInfo) (rc io.ReadCloser, n int64, layerID string, err error) {
+	err = info.Digest.Validate()
+	if err != nil {
+		return nil, -1, "", err
+	}
+	if layerList, ok := s.Layers[info.Digest]; !ok || len(layerList) < 1 {
+		b, err := s.imageRef.transport.store.GetImageBigData(s.ID, info.Digest.String())
+		if err != nil {
+			return nil, -1, "", err
+		}
+		r := bytes.NewReader(b)
+		logrus.Debugf("exporting opaque data as blob %q", info.Digest.String())
+		return ioutil.NopCloser(r), int64(r.Len()), "", nil
+	}
+	// If the blob was "put" more than once, we have multiple layer IDs
+	// which should all produce the same diff.  For the sake of tests that
+	// want to make sure we created different layers each time the blob was
+	// "put", though, cycle through the layers.
+	layerList := s.Layers[info.Digest]
+	position, ok := s.LayerPosition[info.Digest]
+	if !ok {
+		position = 0
+	}
+	s.LayerPosition[info.Digest] = (position + 1) % len(layerList)
+	logrus.Debugf("exporting filesystem layer %q for blob %q", layerList[position], info.Digest)
+	rc, n, err = diffLayer(s.imageRef.transport.store, layerList[position])
+	return rc, n, layerList[position], err
+}
+
+func diffLayer(store storage.Store, layerID string) (rc io.ReadCloser, n int64, err error) {
+	layer, err := store.GetLayer(layerID)
+	if err != nil {
+		return nil, -1, err
+	}
+	layerMeta := storageLayerMetadata{
+		CompressedSize: -1,
+	}
+	if layer.Metadata != "" {
+		if err := json.Unmarshal([]byte(layer.Metadata), &layerMeta); err != nil {
+			return nil, -1, fmt.Errorf("error decoding metadata for layer %q: %v", layerID, err)
+		}
+	}
+	if layerMeta.CompressedSize <= 0 {
+		n = -1
+	} else {
+		n = layerMeta.CompressedSize
+	}
+	diff, err := store.Diff("", layer.ID)
+	if err != nil {
+		return nil, -1, err
+	}
+	return diff, n, nil
+}
+
+func (s *storageImageSource) GetManifest() (manifestBlob []byte, MIMEType string, err error) {
+	manifestBlob, err = s.imageRef.transport.store.GetImageBigData(s.ID, "manifest")
+	return manifestBlob, manifest.GuessMIMEType(manifestBlob), err
+}
+
+func (s *storageImageSource) GetTargetManifest(digest ddigest.Digest) (manifestBlob []byte, MIMEType string, err error) {
+	return nil, "", ErrNoManifestLists
+}
+
+func (s *storageImageSource) GetSignatures() (signatures [][]byte, err error) {
+	var offset int
+	signature, err := s.imageRef.transport.store.GetImageBigData(s.ID, "signatures")
+	if err != nil {
+		return nil, err
+	}
+	sigslice := [][]byte{}
+	for _, length := range s.SignatureSizes {
+		sigslice = append(sigslice, signature[offset:offset+length])
+		offset += length
+	}
+	if offset != len(signature) {
+		return nil, fmt.Errorf("signatures data contained %d extra bytes", len(signatures)-offset)
+	}
+	return sigslice, nil
+}
+
+func (s *storageImageSource) getSize() (int64, error) {
+	var sum int64
+	names, err := s.imageRef.transport.store.ListImageBigData(s.imageRef.id)
+	if err != nil {
+		return -1, fmt.Errorf("error reading image %q: %v", s.imageRef.id, err)
+	}
+	for _, name := range names {
+		bigSize, err := s.imageRef.transport.store.GetImageBigDataSize(s.imageRef.id, name)
+		if err != nil {
+			return -1, fmt.Errorf("error reading data blob size %q for %q: %v", name, s.imageRef.id, err)
+		}
+		sum += bigSize
+	}
+	for _, sigSize := range s.SignatureSizes {
+		sum += int64(sigSize)
+	}
+	for _, layerList := range s.Layers {
+		for _, layerID := range layerList {
+			layer, err := s.imageRef.transport.store.GetLayer(layerID)
+			if err != nil {
+				return -1, err
+			}
+			layerMeta := storageLayerMetadata{
+				Size: -1,
+			}
+			if layer.Metadata != "" {
+				if err := json.Unmarshal([]byte(layer.Metadata), &layerMeta); err != nil {
+					return -1, fmt.Errorf("error decoding metadata for layer %q: %v", layerID, err)
+				}
+			}
+			if layerMeta.Size < 0 {
+				return -1, fmt.Errorf("size for layer %q is unknown, failing getSize()", layerID)
+			}
+			sum += layerMeta.Size
+		}
+	}
+	return sum, nil
+}
+
+func (s *storageImage) Size() (int64, error) {
+	return s.size, nil
+}
+
+// newImage creates an image that also knows its size
+func newImage(s storageReference) (types.Image, error) {
+	src, err := newImageSource(s)
+	if err != nil {
+		return nil, err
+	}
+	img, err := image.FromSource(src)
+	if err != nil {
+		return nil, err
+	}
+	size, err := src.getSize()
+	if err != nil {
+		return nil, err
+	}
+	return &storageImage{Image: img, size: size}, nil
+}

vendor/src/github.com/containers/image/storage/storage_reference.go

@@ -0,0 +1,127 @@
+package storage
+
+import (
+	"strings"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/types"
+)
+
+// A storageReference holds an arbitrary name and/or an ID, which is a 32-byte
+// value hex-encoded into a 64-character string, and a reference to a Store
+// where an image is, or would be, kept.
+type storageReference struct {
+	transport storageTransport
+	reference string
+	id        string
+	name      reference.Named
+}
+
+func newReference(transport storageTransport, reference, id string, name reference.Named) *storageReference {
+	// We take a copy of the transport, which contains a pointer to the
+	// store that it used for resolving this reference, so that the
+	// transport that we'll return from Transport() won't be affected by
+	// further calls to the original transport's SetStore() method.
+	return &storageReference{
+		transport: transport,
+		reference: reference,
+		id:        id,
+		name:      name,
+	}
+}
+
+// Resolve the reference's name to an image ID in the store, if there's already
+// one present with the same name or ID.
+func (s *storageReference) resolveID() string {
+	if s.id == "" {
+		image, err := s.transport.store.GetImage(s.reference)
+		if image != nil && err == nil {
+			s.id = image.ID
+		}
+	}
+	return s.id
+}
+
+// Return a Transport object that defaults to using the same store that we used
+// to build this reference object.
+func (s storageReference) Transport() types.ImageTransport {
+	return &storageTransport{
+		store: s.transport.store,
+	}
+}
+
+// Return a name with a tag, if we have a name to base them on.
+func (s storageReference) DockerReference() reference.Named {
+	return s.name
+}
+
+// Return a name with a tag, prefixed with the graph root and driver name, to
+// disambiguate between images which may be present in multiple stores and
+// share only their names.
+func (s storageReference) StringWithinTransport() string {
+	storeSpec := "[" + s.transport.store.GetGraphDriverName() + "@" + s.transport.store.GetGraphRoot() + "]"
+	if s.name == nil {
+		return storeSpec + "@" + s.id
+	}
+	if s.id == "" {
+		return storeSpec + s.reference
+	}
+	return storeSpec + s.reference + "@" + s.id
+}
+
+func (s storageReference) PolicyConfigurationIdentity() string {
+	return s.StringWithinTransport()
+}
+
+// Also accept policy that's tied to the combination of the graph root and
+// driver name, to apply to all images stored in the Store, and to just the
+// graph root, in case we're using multiple drivers in the same directory for
+// some reason.
+func (s storageReference) PolicyConfigurationNamespaces() []string {
+	storeSpec := "[" + s.transport.store.GetGraphDriverName() + "@" + s.transport.store.GetGraphRoot() + "]"
+	driverlessStoreSpec := "[" + s.transport.store.GetGraphRoot() + "]"
+	namespaces := []string{}
+	if s.name != nil {
+		if s.id != "" {
+			// The reference without the ID is also a valid namespace.
+			namespaces = append(namespaces, storeSpec+s.reference)
+		}
+		components := strings.Split(s.name.FullName(), "/")
+		for len(components) > 0 {
+			namespaces = append(namespaces, storeSpec+strings.Join(components, "/"))
+			components = components[:len(components)-1]
+		}
+	}
+	namespaces = append(namespaces, storeSpec)
+	namespaces = append(namespaces, driverlessStoreSpec)
+	return namespaces
+}
+
+func (s storageReference) NewImage(ctx *types.SystemContext) (types.Image, error) {
+	return newImage(s)
+}
+
+func (s storageReference) DeleteImage(ctx *types.SystemContext) error {
+	id := s.resolveID()
+	if id == "" {
+		logrus.Errorf("reference %q does not resolve to an image ID", s.StringWithinTransport())
+		return ErrNoSuchImage
+	}
+	layers, err := s.transport.store.DeleteImage(id, true)
+	if err == nil {
+		logrus.Debugf("deleted image %q", id)
+		for _, layer := range layers {
+			logrus.Debugf("deleted layer %q", layer)
+		}
+	}
+	return err
+}
+
+func (s storageReference) NewImageSource(ctx *types.SystemContext, requestedManifestMIMETypes []string) (types.ImageSource, error) {
+	return newImageSource(s)
+}
+
+func (s storageReference) NewImageDestination(ctx *types.SystemContext) (types.ImageDestination, error) {
+	return newImageDestination(s)
+}

vendor/src/github.com/containers/image/storage/storage_transport.go

@@ -0,0 +1,285 @@
+package storage
+
+import (
+	"errors"
+	"path/filepath"
+	"regexp"
+	"strings"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/types"
+	"github.com/containers/storage/storage"
+	"github.com/docker/distribution/digest"
+	ddigest "github.com/docker/distribution/digest"
+)
+
+var (
+	// Transport is an ImageTransport that uses either a default
+	// storage.Store or one that's it's explicitly told to use.
+	Transport StoreTransport = &storageTransport{}
+	// ErrInvalidReference is returned when ParseReference() is passed an
+	// empty reference.
+	ErrInvalidReference = errors.New("invalid reference")
+	// ErrPathNotAbsolute is returned when a graph root is not an absolute
+	// path name.
+	ErrPathNotAbsolute = errors.New("path name is not absolute")
+	idRegexp           = regexp.MustCompile("^(sha256:)?([0-9a-fA-F]{64})$")
+)
+
+// StoreTransport is an ImageTransport that uses a storage.Store to parse
+// references, either its own default or one that it's told to use.
+type StoreTransport interface {
+	types.ImageTransport
+	// SetStore sets the default store for this transport.
+	SetStore(storage.Store)
+	// GetImage retrieves the image from the transport's store that's named
+	// by the reference.
+	GetImage(types.ImageReference) (*storage.Image, error)
+	// GetStoreImage retrieves the image from a specified store that's named
+	// by the reference.
+	GetStoreImage(storage.Store, types.ImageReference) (*storage.Image, error)
+	// ParseStoreReference parses a reference, overriding any store
+	// specification that it may contain.
+	ParseStoreReference(store storage.Store, reference string) (*storageReference, error)
+}
+
+type storageTransport struct {
+	store storage.Store
+}
+
+func (s *storageTransport) Name() string {
+	// Still haven't really settled on a name.
+	return "containers-storage"
+}
+
+// SetStore sets the Store object which the Transport will use for parsing
+// references when information about a Store is not directly specified as part
+// of the reference.  If one is not set, the library will attempt to initialize
+// one with default settings when a reference needs to be parsed.  Calling
+// SetStore does not affect previously parsed references.
+func (s *storageTransport) SetStore(store storage.Store) {
+	s.store = store
+}
+
+// ParseStoreReference takes a name or an ID, tries to figure out which it is
+// relative to the given store, and returns it in a reference object.
+func (s storageTransport) ParseStoreReference(store storage.Store, ref string) (*storageReference, error) {
+	var name reference.Named
+	var sum digest.Digest
+	var err error
+	if ref == "" {
+		return nil, ErrInvalidReference
+	}
+	if ref[0] == '[' {
+		// Ignore the store specifier.
+		closeIndex := strings.IndexRune(ref, ']')
+		if closeIndex < 1 {
+			return nil, ErrInvalidReference
+		}
+		ref = ref[closeIndex+1:]
+	}
+	refInfo := strings.SplitN(ref, "@", 2)
+	if len(refInfo) == 1 {
+		// A name.
+		name, err = reference.ParseNamed(refInfo[0])
+		if err != nil {
+			return nil, err
+		}
+	} else if len(refInfo) == 2 {
+		// An ID, possibly preceded by a name.
+		if refInfo[0] != "" {
+			name, err = reference.ParseNamed(refInfo[0])
+			if err != nil {
+				return nil, err
+			}
+		}
+		sum, err = digest.ParseDigest("sha256:" + refInfo[1])
+		if err != nil {
+			return nil, err
+		}
+	} else { // Coverage: len(refInfo) is always 1 or 2
+		// Anything else: store specified in a form we don't
+		// recognize.
+		return nil, ErrInvalidReference
+	}
+	storeSpec := "[" + store.GetGraphDriverName() + "@" + store.GetGraphRoot() + "]"
+	id := ""
+	if sum.Validate() == nil {
+		id = sum.Hex()
+	}
+	refname := ""
+	if name != nil {
+		name = reference.WithDefaultTag(name)
+		refname = verboseName(name)
+	}
+	if refname == "" {
+		logrus.Debugf("parsed reference into %q", storeSpec+"@"+id)
+	} else if id == "" {
+		logrus.Debugf("parsed reference into %q", storeSpec+refname)
+	} else {
+		logrus.Debugf("parsed reference into %q", storeSpec+refname+"@"+id)
+	}
+	return newReference(storageTransport{store: store}, refname, id, name), nil
+}
+
+func (s *storageTransport) GetStore() (storage.Store, error) {
+	// Return the transport's previously-set store.  If we don't have one
+	// of those, initialize one now.
+	if s.store == nil {
+		store, err := storage.GetStore(storage.DefaultStoreOptions)
+		if err != nil {
+			return nil, err
+		}
+		s.store = store
+	}
+	return s.store, nil
+}
+
+// ParseReference takes a name and/or an ID ("_name_"/"@_id_"/"_name_@_id_"),
+// possibly prefixed with a store specifier in the form "[_graphroot_]" or
+// "[_driver_@_graphroot_]", tries to figure out which it is, and returns it in
+// a reference object.  If the _graphroot_ is a location other than the default,
+// it needs to have been previously opened using storage.GetStore(), so that it
+// can figure out which run root goes with the graph root.
+func (s *storageTransport) ParseReference(reference string) (types.ImageReference, error) {
+	store, err := s.GetStore()
+	if err != nil {
+		return nil, err
+	}
+	// Check if there's a store location prefix.  If there is, then it
+	// needs to match a store that was previously initialized using
+	// storage.GetStore(), or be enough to let the storage library fill out
+	// the rest using knowledge that it has from elsewhere.
+	if reference[0] == '[' {
+		closeIndex := strings.IndexRune(reference, ']')
+		if closeIndex < 1 {
+			return nil, ErrInvalidReference
+		}
+		storeSpec := reference[1:closeIndex]
+		reference = reference[closeIndex+1:]
+		storeInfo := strings.SplitN(storeSpec, "@", 2)
+		if len(storeInfo) == 1 && storeInfo[0] != "" {
+			// One component: the graph root.
+			if !filepath.IsAbs(storeInfo[0]) {
+				return nil, ErrPathNotAbsolute
+			}
+			store2, err := storage.GetStore(storage.StoreOptions{
+				GraphRoot: storeInfo[0],
+			})
+			if err != nil {
+				return nil, err
+			}
+			store = store2
+		} else if len(storeInfo) == 2 && storeInfo[0] != "" && storeInfo[1] != "" {
+			// Two components: the driver type and the graph root.
+			if !filepath.IsAbs(storeInfo[1]) {
+				return nil, ErrPathNotAbsolute
+			}
+			store2, err := storage.GetStore(storage.StoreOptions{
+				GraphDriverName: storeInfo[0],
+				GraphRoot:       storeInfo[1],
+			})
+			if err != nil {
+				return nil, err
+			}
+			store = store2
+		} else {
+			// Anything else: store specified in a form we don't
+			// recognize.
+			return nil, ErrInvalidReference
+		}
+	}
+	return s.ParseStoreReference(store, reference)
+}
+
+func (s storageTransport) GetStoreImage(store storage.Store, ref types.ImageReference) (*storage.Image, error) {
+	dref := ref.DockerReference()
+	if dref == nil {
+		if sref, ok := ref.(*storageReference); ok {
+			if sref.id != "" {
+				if img, err := store.GetImage(sref.id); err == nil {
+					return img, nil
+				}
+			}
+		}
+		return nil, ErrInvalidReference
+	}
+	return store.GetImage(verboseName(dref))
+}
+
+func (s *storageTransport) GetImage(ref types.ImageReference) (*storage.Image, error) {
+	store, err := s.GetStore()
+	if err != nil {
+		return nil, err
+	}
+	return s.GetStoreImage(store, ref)
+}
+
+func (s storageTransport) ValidatePolicyConfigurationScope(scope string) error {
+	// Check that there's a store location prefix.  Values we're passed are
+	// expected to come from PolicyConfigurationIdentity or
+	// PolicyConfigurationNamespaces, so if there's no store location,
+	// something's wrong.
+	if scope[0] != '[' {
+		return ErrInvalidReference
+	}
+	// Parse the store location prefix.
+	closeIndex := strings.IndexRune(scope, ']')
+	if closeIndex < 1 {
+		return ErrInvalidReference
+	}
+	storeSpec := scope[1:closeIndex]
+	scope = scope[closeIndex+1:]
+	storeInfo := strings.SplitN(storeSpec, "@", 2)
+	if len(storeInfo) == 1 && storeInfo[0] != "" {
+		// One component: the graph root.
+		if !filepath.IsAbs(storeInfo[0]) {
+			return ErrPathNotAbsolute
+		}
+	} else if len(storeInfo) == 2 && storeInfo[0] != "" && storeInfo[1] != "" {
+		// Two components: the driver type and the graph root.
+		if !filepath.IsAbs(storeInfo[1]) {
+			return ErrPathNotAbsolute
+		}
+	} else {
+		// Anything else: store specified in a form we don't
+		// recognize.
+		return ErrInvalidReference
+	}
+	// That might be all of it, and that's okay.
+	if scope == "" {
+		return nil
+	}
+	// But if there is anything left, it has to be a name, with or without
+	// a tag, with or without an ID, since we don't return namespace values
+	// that are just bare IDs.
+	scopeInfo := strings.SplitN(scope, "@", 2)
+	if len(scopeInfo) == 1 && scopeInfo[0] != "" {
+		_, err := reference.ParseNamed(scopeInfo[0])
+		if err != nil {
+			return err
+		}
+	} else if len(scopeInfo) == 2 && scopeInfo[0] != "" && scopeInfo[1] != "" {
+		_, err := reference.ParseNamed(scopeInfo[0])
+		if err != nil {
+			return err
+		}
+		_, err = ddigest.ParseDigest("sha256:" + scopeInfo[1])
+		if err != nil {
+			return err
+		}
+	} else {
+		return ErrInvalidReference
+	}
+	return nil
+}
+
+func verboseName(name reference.Named) string {
+	name = reference.WithDefaultTag(name)
+	tag := ""
+	if tagged, ok := name.(reference.NamedTagged); ok {
+		tag = tagged.Tag()
+	}
+	return name.FullName() + ":" + tag
+}

vendor/src/github.com/containers/image/transports/transports.go

@@ -6,8 +6,10 @@ import (
 
 	"github.com/containers/image/directory"
 	"github.com/containers/image/docker"
+	"github.com/containers/image/docker/daemon"
 	ociLayout "github.com/containers/image/oci/layout"
 	"github.com/containers/image/openshift"
+	"github.com/containers/image/storage"
 	"github.com/containers/image/types"
 )
 
@@ -16,11 +18,15 @@ var KnownTransports map[string]types.ImageTransport
 
 func init() {
 	KnownTransports = make(map[string]types.ImageTransport)
+	// NOTE: Make sure docs/policy.json.md is updated when adding or updating
+	// a transport.
 	for _, t := range []types.ImageTransport{
 		directory.Transport,
 		docker.Transport,
+		daemon.Transport,
 		ociLayout.Transport,
 		openshift.Transport,
+		storage.Transport,
 	} {
 		name := t.Name()
 		if _, ok := KnownTransports[name]; ok {

vendor/src/github.com/containers/image/types/types.go

@@ -1,10 +1,12 @@
 package types
 
 import (
+	"errors"
 	"io"
 	"time"
 
-	"github.com/docker/docker/reference"
+	"github.com/containers/image/docker/reference"
+	"github.com/docker/distribution/digest"
 )
 
 // ImageTransport is a top-level namespace for ways to to store/load an image.
@@ -70,8 +72,10 @@ type ImageReference interface {
 	// and each following element to be a prefix of the element preceding it.
 	PolicyConfigurationNamespaces() []string
 
-	// NewImage returns a types.Image for this reference.
+	// NewImage returns a types.Image for this reference, possibly specialized for this ImageTransport.
 	// The caller must call .Close() on the returned Image.
+	// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+	// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage.
 	NewImage(ctx *SystemContext) (Image, error)
 	// NewImageSource returns a types.ImageSource for this reference,
 	// asking the backend to use a manifest from requestedManifestMIMETypes if possible.
@@ -86,21 +90,36 @@ type ImageReference interface {
 	DeleteImage(ctx *SystemContext) error
 }
 
+// BlobInfo collects known information about a blob (layer/config).
+// In some situations, some fields may be unknown, in others they may be mandatory; documenting an “unknown” value here does not override that.
+type BlobInfo struct {
+	Digest digest.Digest // "" if unknown.
+	Size   int64         // -1 if unknown
+	URLs   []string
+}
+
 // ImageSource is a service, possibly remote (= slow), to download components of a single image.
 // This is primarily useful for copying images around; for examining their properties, Image (below)
 // is usually more useful.
 // Each ImageSource should eventually be closed by calling Close().
+//
+// WARNING: Various methods which return an object identified by digest generally do not
+// validate that the returned data actually matches that digest; this is the caller’s responsibility.
 type ImageSource interface {
 	// Reference returns the reference used to set up this source, _as specified by the user_
 	// (not as the image itself, or its underlying storage, claims).  This can be used e.g. to determine which public keys are trusted for this image.
 	Reference() ImageReference
 	// Close removes resources associated with an initialized ImageSource, if any.
 	Close()
-	// GetManifest returns the image's manifest along with its MIME type. The empty string is returned if the MIME type is unknown.
+	// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
 	// It may use a remote (= slow) service.
 	GetManifest() ([]byte, string, error)
+	// GetTargetManifest returns an image's manifest given a digest. This is mainly used to retrieve a single image's manifest
+	// out of a manifest list.
+	GetTargetManifest(digest digest.Digest) ([]byte, string, error)
 	// GetBlob returns a stream for the specified blob, and the blob’s size (or -1 if unknown).
-	GetBlob(digest string) (io.ReadCloser, int64, error)
+	// The Digest field in BlobInfo is guaranteed to be provided; Size may be -1.
+	GetBlob(BlobInfo) (io.ReadCloser, int64, error)
 	// GetSignatures returns the image's signatures.  It may use a remote (= slow) service.
 	GetSignatures() ([][]byte, error)
 }
@@ -109,6 +128,7 @@ type ImageSource interface {
 //
 // There is a specific required order for some of the calls:
 // PutBlob on the various blobs, if any, MUST be called before PutManifest (manifest references blobs, which may be created or compressed only at push time)
+// ReapplyBlob, if used, MUST only be called if HasBlob returned true for the same blob digest
 // PutSignatures, if called, MUST be called after PutManifest (signatures reference manifest contents)
 // Finally, Commit MUST be called if the caller wants the image, as formed by the components saved above, to persist.
 //
@@ -126,14 +146,24 @@ type ImageDestination interface {
 	// SupportsSignatures returns an error (to be displayed to the user) if the destination certainly can't store signatures.
 	// Note: It is still possible for PutSignatures to fail if SupportsSignatures returns nil.
 	SupportsSignatures() error
+	// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination.
+	ShouldCompressLayers() bool
 
-	// PutBlob writes contents of stream and returns its computed digest and size.
-	// A digest can be optionally provided if known, the specific image destination can decide to play with it or not.
-	// The length of stream is expected to be expectedSize; if expectedSize == -1, it is not known.
+	// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+	// uploaded to the image destination, true otherwise.
+	AcceptsForeignLayerURLs() bool
+
+	// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+	// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+	// inputInfo.Size is the expected length of stream, if known.
 	// WARNING: The contents of stream are being verified on the fly.  Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
 	// to any other readers for download using the supplied digest.
 	// If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlob MUST 1) fail, and 2) delete any data stored so far.
-	PutBlob(stream io.Reader, digest string, expectedSize int64) (string, int64, error)
+	PutBlob(stream io.Reader, inputInfo BlobInfo) (BlobInfo, error)
+	// HasBlob returns true iff the image destination already contains a blob with the matching digest which can be reapplied using ReapplyBlob.  Unlike PutBlob, the digest can not be empty.  If HasBlob returns true, the size of the blob must also be returned.  A false result will often be accompanied by an ErrBlobNotFound error.
+	HasBlob(info BlobInfo) (bool, int64, error)
+	// ReapplyBlob informs the image destination that a blob for which HasBlob previously returned true would have been passed to PutBlob if it had returned false.  Like HasBlob and unlike PutBlob, the digest can not be empty.  If the blob is a filesystem layer, this signifies that the changes it describes need to be applied again when composing a filesystem tree.
+	ReapplyBlob(info BlobInfo) (BlobInfo, error)
 	// FIXME? This should also receive a MIME type if known, to differentiate between schema versions.
 	PutManifest([]byte) error
 	PutSignatures(signatures [][]byte) error
@@ -144,26 +174,69 @@ type ImageDestination interface {
 	Commit() error
 }
 
-// Image is the primary API for inspecting properties of images.
-// Each Image should eventually be closed by calling Close().
-type Image interface {
+// UnparsedImage is an Image-to-be; until it is verified and accepted, it only caries its identity and caches manifest and signature blobs.
+// Thus, an UnparsedImage can be created from an ImageSource simply by fetching blobs without interpreting them,
+// allowing cryptographic signature verification to happen first, before even fetching the manifest, or parsing anything else.
+// This also makes the UnparsedImage→Image conversion an explicitly visible step.
+// Each UnparsedImage should eventually be closed by calling Close().
+type UnparsedImage interface {
 	// Reference returns the reference used to set up this source, _as specified by the user_
 	// (not as the image itself, or its underlying storage, claims).  This can be used e.g. to determine which public keys are trusted for this image.
 	Reference() ImageReference
-	// Close removes resources associated with an initialized Image, if any.
+	// Close removes resources associated with an initialized UnparsedImage, if any.
 	Close()
-	// ref to repository?
 	// Manifest is like ImageSource.GetManifest, but the result is cached; it is OK to call this however often you need.
-	// NOTE: It is essential for signature verification that Manifest returns the manifest from which BlobDigests is computed.
 	Manifest() ([]byte, string, error)
 	// Signatures is like ImageSource.GetSignatures, but the result is cached; it is OK to call this however often you need.
 	Signatures() ([][]byte, error)
-	// BlobDigests returns a list of blob digests referenced by this image.
-	// The list will not contain duplicates; it is not intended to correspond to the "history" or "parent chain" of a Docker image.
-	// NOTE: It is essential for signature verification that BlobDigests is computed from the same manifest which is returned by Manifest().
-	BlobDigests() ([]string, error)
+}
+
+// Image is the primary API for inspecting properties of images.
+// Each Image should eventually be closed by calling Close().
+type Image interface {
+	// Note that Reference may return nil in the return value of UpdatedImage!
+	UnparsedImage
+	// ConfigInfo returns a complete BlobInfo for the separate config object, or a BlobInfo{Digest:""} if there isn't a separate object.
+	// Note that the config object may not exist in the underlying storage in the return value of UpdatedImage! Use ConfigBlob() below.
+	ConfigInfo() BlobInfo
+	// ConfigBlob returns the blob described by ConfigInfo, iff ConfigInfo().Digest != ""; nil otherwise.
+	// The result is cached; it is OK to call this however often you need.
+	ConfigBlob() ([]byte, error)
+	// LayerInfos returns a list of BlobInfos of layers referenced by this image, in order (the root layer first, and then successive layered layers).
+	// The Digest field is guaranteed to be provided; Size may be -1.
+	// WARNING: The list may contain duplicates, and they are semantically relevant.
+	LayerInfos() []BlobInfo
 	// Inspect returns various information for (skopeo inspect) parsed from the manifest and configuration.
 	Inspect() (*ImageInspectInfo, error)
+	// UpdatedImageNeedsLayerDiffIDs returns true iff UpdatedImage(options) needs InformationOnly.LayerDiffIDs.
+	// This is a horribly specific interface, but computing InformationOnly.LayerDiffIDs can be very expensive to compute
+	// (most importantly it forces us to download the full layers even if they are already present at the destination).
+	UpdatedImageNeedsLayerDiffIDs(options ManifestUpdateOptions) bool
+	// UpdatedImage returns a types.Image modified according to options.
+	// Everything in options.InformationOnly should be provided, other fields should be set only if a modification is desired.
+	// This does not change the state of the original Image object.
+	UpdatedImage(options ManifestUpdateOptions) (Image, error)
+	// IsMultiImage returns true if the image's manifest is a list of images, false otherwise.
+	IsMultiImage() bool
+	// Size returns an approximation of the amount of disk space which is consumed by the image in its current
+	// location.  If the size is not known, -1 will be returned.
+	Size() (int64, error)
+}
+
+// ManifestUpdateOptions is a way to pass named optional arguments to Image.UpdatedManifest
+type ManifestUpdateOptions struct {
+	LayerInfos       []BlobInfo // Complete BlobInfos (size+digest+urls) which should replace the originals, in order (the root layer first, and then successive layered layers)
+	ManifestMIMEType string
+	// The values below are NOT requests to modify the image; they provide optional context which may or may not be used.
+	InformationOnly ManifestUpdateInformation
+}
+
+// ManifestUpdateInformation is a component of ManifestUpdateOptions, named here
+// only to make writing struct literals possible.
+type ManifestUpdateInformation struct {
+	Destination  ImageDestination // and yes, UpdatedManifest may write to Destination (see the schema2 → schema1 conversion logic in image/docker_schema2.go)
+	LayerInfos   []BlobInfo       // Complete BlobInfos (size+digest) which have been uploaded, in order (the root layer first, and then successive layered layers)
+	LayerDiffIDs []digest.Digest  // Digest values for the _uncompressed_ contents of the blobs which have been uploaded, in the same order.
 }
 
 // ImageInspectInfo is a set of metadata describing Docker images, primarily their manifest and configuration.
@@ -179,6 +252,12 @@ type ImageInspectInfo struct {
 	Layers        []string
 }
 
+// DockerAuthConfig contains authorization information for connecting to a registry.
+type DockerAuthConfig struct {
+	Username string
+	Password string
+}
+
 // SystemContext allows parametrizing access to implicitly-accessed resources,
 // like configuration files in /etc and users' login state in their home directory.
 // Various components can share the same field only if their semantics is exactly
@@ -200,6 +279,22 @@ type SystemContext struct {
 	RegistriesDirPath string
 
 	// === docker.Transport overrides ===
-	DockerCertPath              string // If not "", a directory containing "cert.pem" and "key.pem" used when talking to a Docker Registry
-	DockerInsecureSkipTLSVerify bool   // Allow contacting docker registries over HTTP, or HTTPS with failed TLS verification. Note that this does not affect other TLS connections.
+	// If not "", a directory containing a CA certificate (ending with ".crt"),
+	// a client certificate (ending with ".cert") and a client ceritificate key
+	// (ending with ".key") used when talking to a Docker Registry.
+	DockerCertPath              string
+	DockerInsecureSkipTLSVerify bool // Allow contacting docker registries over HTTP, or HTTPS with failed TLS verification. Note that this does not affect other TLS connections.
+	// if nil, the library tries to parse ~/.docker/config.json to retrieve credentials
+	DockerAuthConfig *DockerAuthConfig
+	// if not "", an User-Agent header is added to each request when contacting a registry.
+	DockerRegistryUserAgent string
+	// if true, a V1 ping attempt isn't done to give users a better error. Default is false.
+	// Note that this field is used mainly to integrate containers/image into projectatomic/docker
+	// in order to not break any existing docker's integration tests.
+	DockerDisableV1Ping bool
 }
+
+var (
+	// ErrBlobNotFound can be returned by an ImageDestination's HasBlob() method
+	ErrBlobNotFound = errors.New("no such blob present")
+)

vendor/src/github.com/containers/storage/LICENSE

@@ -0,0 +1,191 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        https://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
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+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
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+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
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+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
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+          of the following places: within a NOTICE text file distributed
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+          wherever such third-party notices normally appear. The contents
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+          notices within Derivative Works that You distribute, alongside
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+
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+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   Copyright 2013-2016 Docker, Inc.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       https://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/src/github.com/containers/storage/drivers/aufs/aufs.go

@@ -0,0 +1,586 @@
+// +build linux
+
+/*
+
+aufs driver directory structure
+
+  .
+  ├── layers // Metadata of layers
+  │   ├── 1
+  │   ├── 2
+  │   └── 3
+  ├── diff  // Content of the layer
+  │   ├── 1  // Contains layers that need to be mounted for the id
+  │   ├── 2
+  │   └── 3
+  └── mnt    // Mount points for the rw layers to be mounted
+      ├── 1
+      ├── 2
+      └── 3
+
+*/
+
+package aufs
+
+import (
+	"bufio"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"path/filepath"
+	"strings"
+	"sync"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/vbatts/tar-split/tar/storage"
+
+	"github.com/containers/storage/drivers"
+	"github.com/containers/storage/pkg/archive"
+	"github.com/containers/storage/pkg/chrootarchive"
+	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/idtools"
+	mountpk "github.com/containers/storage/pkg/mount"
+	"github.com/containers/storage/pkg/stringid"
+
+	"github.com/opencontainers/runc/libcontainer/label"
+	rsystem "github.com/opencontainers/runc/libcontainer/system"
+)
+
+var (
+	// ErrAufsNotSupported is returned if aufs is not supported by the host.
+	ErrAufsNotSupported = fmt.Errorf("AUFS was not found in /proc/filesystems")
+	// ErrAufsNested means aufs cannot be used bc we are in a user namespace
+	ErrAufsNested = fmt.Errorf("AUFS cannot be used in non-init user namespace")
+	backingFs     = "<unknown>"
+
+	enableDirpermLock sync.Once
+	enableDirperm     bool
+)
+
+func init() {
+	graphdriver.Register("aufs", Init)
+}
+
+// Driver contains information about the filesystem mounted.
+type Driver struct {
+	sync.Mutex
+	root          string
+	uidMaps       []idtools.IDMap
+	gidMaps       []idtools.IDMap
+	ctr           *graphdriver.RefCounter
+	pathCacheLock sync.Mutex
+	pathCache     map[string]string
+}
+
+// Init returns a new AUFS driver.
+// An error is returned if AUFS is not supported.
+func Init(root string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
+
+	// Try to load the aufs kernel module
+	if err := supportsAufs(); err != nil {
+		return nil, graphdriver.ErrNotSupported
+	}
+
+	fsMagic, err := graphdriver.GetFSMagic(root)
+	if err != nil {
+		return nil, err
+	}
+	if fsName, ok := graphdriver.FsNames[fsMagic]; ok {
+		backingFs = fsName
+	}
+
+	switch fsMagic {
+	case graphdriver.FsMagicAufs, graphdriver.FsMagicBtrfs, graphdriver.FsMagicEcryptfs:
+		logrus.Errorf("AUFS is not supported over %s", backingFs)
+		return nil, graphdriver.ErrIncompatibleFS
+	}
+
+	paths := []string{
+		"mnt",
+		"diff",
+		"layers",
+	}
+
+	a := &Driver{
+		root:      root,
+		uidMaps:   uidMaps,
+		gidMaps:   gidMaps,
+		pathCache: make(map[string]string),
+		ctr:       graphdriver.NewRefCounter(graphdriver.NewFsChecker(graphdriver.FsMagicAufs)),
+	}
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
+	if err != nil {
+		return nil, err
+	}
+	// Create the root aufs driver dir and return
+	// if it already exists
+	// If not populate the dir structure
+	if err := idtools.MkdirAllAs(root, 0700, rootUID, rootGID); err != nil {
+		if os.IsExist(err) {
+			return a, nil
+		}
+		return nil, err
+	}
+
+	if err := mountpk.MakePrivate(root); err != nil {
+		return nil, err
+	}
+
+	// Populate the dir structure
+	for _, p := range paths {
+		if err := idtools.MkdirAllAs(path.Join(root, p), 0700, rootUID, rootGID); err != nil {
+			return nil, err
+		}
+	}
+	return a, nil
+}
+
+// Return a nil error if the kernel supports aufs
+// We cannot modprobe because inside dind modprobe fails
+// to run
+func supportsAufs() error {
+	// We can try to modprobe aufs first before looking at
+	// proc/filesystems for when aufs is supported
+	exec.Command("modprobe", "aufs").Run()
+
+	if rsystem.RunningInUserNS() {
+		return ErrAufsNested
+	}
+
+	f, err := os.Open("/proc/filesystems")
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	s := bufio.NewScanner(f)
+	for s.Scan() {
+		if strings.Contains(s.Text(), "aufs") {
+			return nil
+		}
+	}
+	return ErrAufsNotSupported
+}
+
+func (a *Driver) rootPath() string {
+	return a.root
+}
+
+func (*Driver) String() string {
+	return "aufs"
+}
+
+// Status returns current information about the filesystem such as root directory, number of directories mounted, etc.
+func (a *Driver) Status() [][2]string {
+	ids, _ := loadIds(path.Join(a.rootPath(), "layers"))
+	return [][2]string{
+		{"Root Dir", a.rootPath()},
+		{"Backing Filesystem", backingFs},
+		{"Dirs", fmt.Sprintf("%d", len(ids))},
+		{"Dirperm1 Supported", fmt.Sprintf("%v", useDirperm())},
+	}
+}
+
+// GetMetadata not implemented
+func (a *Driver) GetMetadata(id string) (map[string]string, error) {
+	return nil, nil
+}
+
+// Exists returns true if the given id is registered with
+// this driver
+func (a *Driver) Exists(id string) bool {
+	if _, err := os.Lstat(path.Join(a.rootPath(), "layers", id)); err != nil {
+		return false
+	}
+	return true
+}
+
+// CreateReadWrite creates a layer that is writable for use as a container
+// file system.
+func (a *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	return a.Create(id, parent, mountLabel, storageOpt)
+}
+
+// Create three folders for each id
+// mnt, layers, and diff
+func (a *Driver) Create(id, parent, mountLabel string, storageOpt map[string]string) error {
+
+	if len(storageOpt) != 0 {
+		return fmt.Errorf("--storage-opt is not supported for aufs")
+	}
+
+	if err := a.createDirsFor(id); err != nil {
+		return err
+	}
+	// Write the layers metadata
+	f, err := os.Create(path.Join(a.rootPath(), "layers", id))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if parent != "" {
+		ids, err := getParentIds(a.rootPath(), parent)
+		if err != nil {
+			return err
+		}
+
+		if _, err := fmt.Fprintln(f, parent); err != nil {
+			return err
+		}
+		for _, i := range ids {
+			if _, err := fmt.Fprintln(f, i); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+// createDirsFor creates two directories for the given id.
+// mnt and diff
+func (a *Driver) createDirsFor(id string) error {
+	paths := []string{
+		"mnt",
+		"diff",
+	}
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(a.uidMaps, a.gidMaps)
+	if err != nil {
+		return err
+	}
+	// Directory permission is 0755.
+	// The path of directories are <aufs_root_path>/mnt/<image_id>
+	// and <aufs_root_path>/diff/<image_id>
+	for _, p := range paths {
+		if err := idtools.MkdirAllAs(path.Join(a.rootPath(), p, id), 0755, rootUID, rootGID); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Remove will unmount and remove the given id.
+func (a *Driver) Remove(id string) error {
+	a.pathCacheLock.Lock()
+	mountpoint, exists := a.pathCache[id]
+	a.pathCacheLock.Unlock()
+	if !exists {
+		mountpoint = a.getMountpoint(id)
+	}
+	if err := a.unmount(mountpoint); err != nil {
+		// no need to return here, we can still try to remove since the `Rename` will fail below if still mounted
+		logrus.Debugf("aufs: error while unmounting %s: %v", mountpoint, err)
+	}
+
+	// Atomically remove each directory in turn by first moving it out of the
+	// way (so that docker doesn't find it anymore) before doing removal of
+	// the whole tree.
+	tmpMntPath := path.Join(a.mntPath(), fmt.Sprintf("%s-removing", id))
+	if err := os.Rename(mountpoint, tmpMntPath); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	defer os.RemoveAll(tmpMntPath)
+
+	tmpDiffpath := path.Join(a.diffPath(), fmt.Sprintf("%s-removing", id))
+	if err := os.Rename(a.getDiffPath(id), tmpDiffpath); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	defer os.RemoveAll(tmpDiffpath)
+
+	// Remove the layers file for the id
+	if err := os.Remove(path.Join(a.rootPath(), "layers", id)); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+
+	a.pathCacheLock.Lock()
+	delete(a.pathCache, id)
+	a.pathCacheLock.Unlock()
+	return nil
+}
+
+// Get returns the rootfs path for the id.
+// This will mount the dir at it's given path
+func (a *Driver) Get(id, mountLabel string) (string, error) {
+	parents, err := a.getParentLayerPaths(id)
+	if err != nil && !os.IsNotExist(err) {
+		return "", err
+	}
+
+	a.pathCacheLock.Lock()
+	m, exists := a.pathCache[id]
+	a.pathCacheLock.Unlock()
+
+	if !exists {
+		m = a.getDiffPath(id)
+		if len(parents) > 0 {
+			m = a.getMountpoint(id)
+		}
+	}
+	if count := a.ctr.Increment(m); count > 1 {
+		return m, nil
+	}
+
+	// If a dir does not have a parent ( no layers )do not try to mount
+	// just return the diff path to the data
+	if len(parents) > 0 {
+		if err := a.mount(id, m, mountLabel, parents); err != nil {
+			return "", err
+		}
+	}
+
+	a.pathCacheLock.Lock()
+	a.pathCache[id] = m
+	a.pathCacheLock.Unlock()
+	return m, nil
+}
+
+// Put unmounts and updates list of active mounts.
+func (a *Driver) Put(id string) error {
+	a.pathCacheLock.Lock()
+	m, exists := a.pathCache[id]
+	if !exists {
+		m = a.getMountpoint(id)
+		a.pathCache[id] = m
+	}
+	a.pathCacheLock.Unlock()
+	if count := a.ctr.Decrement(m); count > 0 {
+		return nil
+	}
+
+	err := a.unmount(m)
+	if err != nil {
+		logrus.Debugf("Failed to unmount %s aufs: %v", id, err)
+	}
+	return err
+}
+
+// Diff produces an archive of the changes between the specified
+// layer and its parent layer which may be "".
+func (a *Driver) Diff(id, parent string) (archive.Archive, error) {
+	// AUFS doesn't need the parent layer to produce a diff.
+	return archive.TarWithOptions(path.Join(a.rootPath(), "diff", id), &archive.TarOptions{
+		Compression:     archive.Uncompressed,
+		ExcludePatterns: []string{archive.WhiteoutMetaPrefix + "*", "!" + archive.WhiteoutOpaqueDir},
+		UIDMaps:         a.uidMaps,
+		GIDMaps:         a.gidMaps,
+	})
+}
+
+type fileGetNilCloser struct {
+	storage.FileGetter
+}
+
+func (f fileGetNilCloser) Close() error {
+	return nil
+}
+
+// DiffGetter returns a FileGetCloser that can read files from the directory that
+// contains files for the layer differences. Used for direct access for tar-split.
+func (a *Driver) DiffGetter(id string) (graphdriver.FileGetCloser, error) {
+	p := path.Join(a.rootPath(), "diff", id)
+	return fileGetNilCloser{storage.NewPathFileGetter(p)}, nil
+}
+
+func (a *Driver) applyDiff(id string, diff archive.Reader) error {
+	return chrootarchive.UntarUncompressed(diff, path.Join(a.rootPath(), "diff", id), &archive.TarOptions{
+		UIDMaps: a.uidMaps,
+		GIDMaps: a.gidMaps,
+	})
+}
+
+// DiffSize calculates the changes between the specified id
+// and its parent and returns the size in bytes of the changes
+// relative to its base filesystem directory.
+func (a *Driver) DiffSize(id, parent string) (size int64, err error) {
+	// AUFS doesn't need the parent layer to calculate the diff size.
+	return directory.Size(path.Join(a.rootPath(), "diff", id))
+}
+
+// ApplyDiff extracts the changeset from the given diff into the
+// layer with the specified id and parent, returning the size of the
+// new layer in bytes.
+func (a *Driver) ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error) {
+	// AUFS doesn't need the parent id to apply the diff.
+	if err = a.applyDiff(id, diff); err != nil {
+		return
+	}
+
+	return a.DiffSize(id, parent)
+}
+
+// Changes produces a list of changes between the specified layer
+// and its parent layer. If parent is "", then all changes will be ADD changes.
+func (a *Driver) Changes(id, parent string) ([]archive.Change, error) {
+	// AUFS doesn't have snapshots, so we need to get changes from all parent
+	// layers.
+	layers, err := a.getParentLayerPaths(id)
+	if err != nil {
+		return nil, err
+	}
+	return archive.Changes(layers, path.Join(a.rootPath(), "diff", id))
+}
+
+func (a *Driver) getParentLayerPaths(id string) ([]string, error) {
+	parentIds, err := getParentIds(a.rootPath(), id)
+	if err != nil {
+		return nil, err
+	}
+	layers := make([]string, len(parentIds))
+
+	// Get the diff paths for all the parent ids
+	for i, p := range parentIds {
+		layers[i] = path.Join(a.rootPath(), "diff", p)
+	}
+	return layers, nil
+}
+
+func (a *Driver) mount(id string, target string, mountLabel string, layers []string) error {
+	a.Lock()
+	defer a.Unlock()
+
+	// If the id is mounted or we get an error return
+	if mounted, err := a.mounted(target); err != nil || mounted {
+		return err
+	}
+
+	rw := a.getDiffPath(id)
+
+	if err := a.aufsMount(layers, rw, target, mountLabel); err != nil {
+		return fmt.Errorf("error creating aufs mount to %s: %v", target, err)
+	}
+	return nil
+}
+
+func (a *Driver) unmount(mountPath string) error {
+	a.Lock()
+	defer a.Unlock()
+
+	if mounted, err := a.mounted(mountPath); err != nil || !mounted {
+		return err
+	}
+	if err := Unmount(mountPath); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (a *Driver) mounted(mountpoint string) (bool, error) {
+	return graphdriver.Mounted(graphdriver.FsMagicAufs, mountpoint)
+}
+
+// Cleanup aufs and unmount all mountpoints
+func (a *Driver) Cleanup() error {
+	var dirs []string
+	if err := filepath.Walk(a.mntPath(), func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if !info.IsDir() {
+			return nil
+		}
+		dirs = append(dirs, path)
+		return nil
+	}); err != nil {
+		return err
+	}
+
+	for _, m := range dirs {
+		if err := a.unmount(m); err != nil {
+			logrus.Debugf("aufs error unmounting %s: %s", stringid.TruncateID(m), err)
+		}
+	}
+	return mountpk.Unmount(a.root)
+}
+
+func (a *Driver) aufsMount(ro []string, rw, target, mountLabel string) (err error) {
+	defer func() {
+		if err != nil {
+			Unmount(target)
+		}
+	}()
+
+	// Mount options are clipped to page size(4096 bytes). If there are more
+	// layers then these are remounted individually using append.
+
+	offset := 54
+	if useDirperm() {
+		offset += len("dirperm1")
+	}
+	b := make([]byte, syscall.Getpagesize()-len(mountLabel)-offset) // room for xino & mountLabel
+	bp := copy(b, fmt.Sprintf("br:%s=rw", rw))
+
+	firstMount := true
+	i := 0
+
+	for {
+		for ; i < len(ro); i++ {
+			layer := fmt.Sprintf(":%s=ro+wh", ro[i])
+
+			if firstMount {
+				if bp+len(layer) > len(b) {
+					break
+				}
+				bp += copy(b[bp:], layer)
+			} else {
+				data := label.FormatMountLabel(fmt.Sprintf("append%s", layer), mountLabel)
+				if err = mount("none", target, "aufs", syscall.MS_REMOUNT, data); err != nil {
+					return
+				}
+			}
+		}
+
+		if firstMount {
+			opts := "dio,xino=/dev/shm/aufs.xino"
+			if useDirperm() {
+				opts += ",dirperm1"
+			}
+			data := label.FormatMountLabel(fmt.Sprintf("%s,%s", string(b[:bp]), opts), mountLabel)
+			if err = mount("none", target, "aufs", 0, data); err != nil {
+				return
+			}
+			firstMount = false
+		}
+
+		if i == len(ro) {
+			break
+		}
+	}
+
+	return
+}
+
+// useDirperm checks dirperm1 mount option can be used with the current
+// version of aufs.
+func useDirperm() bool {
+	enableDirpermLock.Do(func() {
+		base, err := ioutil.TempDir("", "docker-aufs-base")
+		if err != nil {
+			logrus.Errorf("error checking dirperm1: %v", err)
+			return
+		}
+		defer os.RemoveAll(base)
+
+		union, err := ioutil.TempDir("", "docker-aufs-union")
+		if err != nil {
+			logrus.Errorf("error checking dirperm1: %v", err)
+			return
+		}
+		defer os.RemoveAll(union)
+
+		opts := fmt.Sprintf("br:%s,dirperm1,xino=/dev/shm/aufs.xino", base)
+		if err := mount("none", union, "aufs", 0, opts); err != nil {
+			return
+		}
+		enableDirperm = true
+		if err := Unmount(union); err != nil {
+			logrus.Errorf("error checking dirperm1: failed to unmount %v", err)
+		}
+	})
+	return enableDirperm
+}

vendor/src/github.com/containers/storage/drivers/aufs/dirs.go

@@ -0,0 +1,64 @@
+// +build linux
+
+package aufs
+
+import (
+	"bufio"
+	"io/ioutil"
+	"os"
+	"path"
+)
+
+// Return all the directories
+func loadIds(root string) ([]string, error) {
+	dirs, err := ioutil.ReadDir(root)
+	if err != nil {
+		return nil, err
+	}
+	out := []string{}
+	for _, d := range dirs {
+		if !d.IsDir() {
+			out = append(out, d.Name())
+		}
+	}
+	return out, nil
+}
+
+// Read the layers file for the current id and return all the
+// layers represented by new lines in the file
+//
+// If there are no lines in the file then the id has no parent
+// and an empty slice is returned.
+func getParentIds(root, id string) ([]string, error) {
+	f, err := os.Open(path.Join(root, "layers", id))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	out := []string{}
+	s := bufio.NewScanner(f)
+
+	for s.Scan() {
+		if t := s.Text(); t != "" {
+			out = append(out, s.Text())
+		}
+	}
+	return out, s.Err()
+}
+
+func (a *Driver) getMountpoint(id string) string {
+	return path.Join(a.mntPath(), id)
+}
+
+func (a *Driver) mntPath() string {
+	return path.Join(a.rootPath(), "mnt")
+}
+
+func (a *Driver) getDiffPath(id string) string {
+	return path.Join(a.diffPath(), id)
+}
+
+func (a *Driver) diffPath() string {
+	return path.Join(a.rootPath(), "diff")
+}

vendor/src/github.com/containers/storage/drivers/aufs/mount.go

@@ -0,0 +1,21 @@
+// +build linux
+
+package aufs
+
+import (
+	"os/exec"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+)
+
+// Unmount the target specified.
+func Unmount(target string) error {
+	if err := exec.Command("auplink", target, "flush").Run(); err != nil {
+		logrus.Warnf("Couldn't run auplink before unmount %s: %s", target, err)
+	}
+	if err := syscall.Unmount(target, 0); err != nil {
+		return err
+	}
+	return nil
+}

vendor/src/github.com/containers/storage/drivers/aufs/mount_linux.go

@@ -0,0 +1,7 @@
+package aufs
+
+import "syscall"
+
+func mount(source string, target string, fstype string, flags uintptr, data string) error {
+	return syscall.Mount(source, target, fstype, flags, data)
+}

vendor/src/github.com/containers/storage/drivers/aufs/mount_unsupported.go

@@ -0,0 +1,12 @@
+// +build !linux
+
+package aufs
+
+import "errors"
+
+// MsRemount declared to specify a non-linux system mount.
+const MsRemount = 0
+
+func mount(source string, target string, fstype string, flags uintptr, data string) (err error) {
+	return errors.New("mount is not implemented on this platform")
+}

vendor/src/github.com/containers/storage/drivers/btrfs/btrfs.go

@@ -0,0 +1,520 @@
+// +build linux
+
+package btrfs
+
+/*
+#include <stdlib.h>
+#include <dirent.h>
+#include <btrfs/ioctl.h>
+#include <btrfs/ctree.h>
+
+static void set_name_btrfs_ioctl_vol_args_v2(struct btrfs_ioctl_vol_args_v2* btrfs_struct, const char* value) {
+    snprintf(btrfs_struct->name, BTRFS_SUBVOL_NAME_MAX, "%s", value);
+}
+*/
+import "C"
+
+import (
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"syscall"
+	"unsafe"
+
+	"github.com/containers/storage/drivers"
+	"github.com/containers/storage/pkg/idtools"
+	"github.com/containers/storage/pkg/mount"
+	"github.com/containers/storage/pkg/parsers"
+	"github.com/docker/go-units"
+	"github.com/opencontainers/runc/libcontainer/label"
+)
+
+func init() {
+	graphdriver.Register("btrfs", Init)
+}
+
+var (
+	quotaEnabled  = false
+	userDiskQuota = false
+)
+
+type btrfsOptions struct {
+	minSpace uint64
+	size     uint64
+}
+
+// Init returns a new BTRFS driver.
+// An error is returned if BTRFS is not supported.
+func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
+
+	fsMagic, err := graphdriver.GetFSMagic(home)
+	if err != nil {
+		return nil, err
+	}
+
+	if fsMagic != graphdriver.FsMagicBtrfs {
+		return nil, graphdriver.ErrPrerequisites
+	}
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
+	if err != nil {
+		return nil, err
+	}
+	if err := idtools.MkdirAllAs(home, 0700, rootUID, rootGID); err != nil {
+		return nil, err
+	}
+
+	if err := mount.MakePrivate(home); err != nil {
+		return nil, err
+	}
+
+	opt, err := parseOptions(options)
+	if err != nil {
+		return nil, err
+	}
+
+	if userDiskQuota {
+		if err := subvolEnableQuota(home); err != nil {
+			return nil, err
+		}
+		quotaEnabled = true
+	}
+
+	driver := &Driver{
+		home:    home,
+		uidMaps: uidMaps,
+		gidMaps: gidMaps,
+		options: opt,
+	}
+
+	return graphdriver.NewNaiveDiffDriver(driver, uidMaps, gidMaps), nil
+}
+
+func parseOptions(opt []string) (btrfsOptions, error) {
+	var options btrfsOptions
+	for _, option := range opt {
+		key, val, err := parsers.ParseKeyValueOpt(option)
+		if err != nil {
+			return options, err
+		}
+		key = strings.ToLower(key)
+		switch key {
+		case "btrfs.min_space":
+			minSpace, err := units.RAMInBytes(val)
+			if err != nil {
+				return options, err
+			}
+			userDiskQuota = true
+			options.minSpace = uint64(minSpace)
+		default:
+			return options, fmt.Errorf("Unknown option %s", key)
+		}
+	}
+	return options, nil
+}
+
+// Driver contains information about the filesystem mounted.
+type Driver struct {
+	//root of the file system
+	home    string
+	uidMaps []idtools.IDMap
+	gidMaps []idtools.IDMap
+	options btrfsOptions
+}
+
+// String prints the name of the driver (btrfs).
+func (d *Driver) String() string {
+	return "btrfs"
+}
+
+// Status returns current driver information in a two dimensional string array.
+// Output contains "Build Version" and "Library Version" of the btrfs libraries used.
+// Version information can be used to check compatibility with your kernel.
+func (d *Driver) Status() [][2]string {
+	status := [][2]string{}
+	if bv := btrfsBuildVersion(); bv != "-" {
+		status = append(status, [2]string{"Build Version", bv})
+	}
+	if lv := btrfsLibVersion(); lv != -1 {
+		status = append(status, [2]string{"Library Version", fmt.Sprintf("%d", lv)})
+	}
+	return status
+}
+
+// GetMetadata returns empty metadata for this driver.
+func (d *Driver) GetMetadata(id string) (map[string]string, error) {
+	return nil, nil
+}
+
+// Cleanup unmounts the home directory.
+func (d *Driver) Cleanup() error {
+	if quotaEnabled {
+		if err := subvolDisableQuota(d.home); err != nil {
+			return err
+		}
+	}
+
+	return mount.Unmount(d.home)
+}
+
+func free(p *C.char) {
+	C.free(unsafe.Pointer(p))
+}
+
+func openDir(path string) (*C.DIR, error) {
+	Cpath := C.CString(path)
+	defer free(Cpath)
+
+	dir := C.opendir(Cpath)
+	if dir == nil {
+		return nil, fmt.Errorf("Can't open dir")
+	}
+	return dir, nil
+}
+
+func closeDir(dir *C.DIR) {
+	if dir != nil {
+		C.closedir(dir)
+	}
+}
+
+func getDirFd(dir *C.DIR) uintptr {
+	return uintptr(C.dirfd(dir))
+}
+
+func subvolCreate(path, name string) error {
+	dir, err := openDir(path)
+	if err != nil {
+		return err
+	}
+	defer closeDir(dir)
+
+	var args C.struct_btrfs_ioctl_vol_args
+	for i, c := range []byte(name) {
+		args.name[i] = C.char(c)
+	}
+
+	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, getDirFd(dir), C.BTRFS_IOC_SUBVOL_CREATE,
+		uintptr(unsafe.Pointer(&args)))
+	if errno != 0 {
+		return fmt.Errorf("Failed to create btrfs subvolume: %v", errno.Error())
+	}
+	return nil
+}
+
+func subvolSnapshot(src, dest, name string) error {
+	srcDir, err := openDir(src)
+	if err != nil {
+		return err
+	}
+	defer closeDir(srcDir)
+
+	destDir, err := openDir(dest)
+	if err != nil {
+		return err
+	}
+	defer closeDir(destDir)
+
+	var args C.struct_btrfs_ioctl_vol_args_v2
+	args.fd = C.__s64(getDirFd(srcDir))
+
+	var cs = C.CString(name)
+	C.set_name_btrfs_ioctl_vol_args_v2(&args, cs)
+	C.free(unsafe.Pointer(cs))
+
+	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, getDirFd(destDir), C.BTRFS_IOC_SNAP_CREATE_V2,
+		uintptr(unsafe.Pointer(&args)))
+	if errno != 0 {
+		return fmt.Errorf("Failed to create btrfs snapshot: %v", errno.Error())
+	}
+	return nil
+}
+
+func isSubvolume(p string) (bool, error) {
+	var bufStat syscall.Stat_t
+	if err := syscall.Lstat(p, &bufStat); err != nil {
+		return false, err
+	}
+
+	// return true if it is a btrfs subvolume
+	return bufStat.Ino == C.BTRFS_FIRST_FREE_OBJECTID, nil
+}
+
+func subvolDelete(dirpath, name string) error {
+	dir, err := openDir(dirpath)
+	if err != nil {
+		return err
+	}
+	defer closeDir(dir)
+	fullPath := path.Join(dirpath, name)
+
+	var args C.struct_btrfs_ioctl_vol_args
+
+	// walk the btrfs subvolumes
+	walkSubvolumes := func(p string, f os.FileInfo, err error) error {
+		if err != nil {
+			if os.IsNotExist(err) && p != fullPath {
+				// missing most likely because the path was a subvolume that got removed in the previous iteration
+				// since it's gone anyway, we don't care
+				return nil
+			}
+			return fmt.Errorf("error walking subvolumes: %v", err)
+		}
+		// we want to check children only so skip itself
+		// it will be removed after the filepath walk anyways
+		if f.IsDir() && p != fullPath {
+			sv, err := isSubvolume(p)
+			if err != nil {
+				return fmt.Errorf("Failed to test if %s is a btrfs subvolume: %v", p, err)
+			}
+			if sv {
+				if err := subvolDelete(path.Dir(p), f.Name()); err != nil {
+					return fmt.Errorf("Failed to destroy btrfs child subvolume (%s) of parent (%s): %v", p, dirpath, err)
+				}
+			}
+		}
+		return nil
+	}
+	if err := filepath.Walk(path.Join(dirpath, name), walkSubvolumes); err != nil {
+		return fmt.Errorf("Recursively walking subvolumes for %s failed: %v", dirpath, err)
+	}
+
+	// all subvolumes have been removed
+	// now remove the one originally passed in
+	for i, c := range []byte(name) {
+		args.name[i] = C.char(c)
+	}
+	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, getDirFd(dir), C.BTRFS_IOC_SNAP_DESTROY,
+		uintptr(unsafe.Pointer(&args)))
+	if errno != 0 {
+		return fmt.Errorf("Failed to destroy btrfs snapshot %s for %s: %v", dirpath, name, errno.Error())
+	}
+	return nil
+}
+
+func subvolEnableQuota(path string) error {
+	dir, err := openDir(path)
+	if err != nil {
+		return err
+	}
+	defer closeDir(dir)
+
+	var args C.struct_btrfs_ioctl_quota_ctl_args
+	args.cmd = C.BTRFS_QUOTA_CTL_ENABLE
+	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, getDirFd(dir), C.BTRFS_IOC_QUOTA_CTL,
+		uintptr(unsafe.Pointer(&args)))
+	if errno != 0 {
+		return fmt.Errorf("Failed to enable btrfs quota for %s: %v", dir, errno.Error())
+	}
+
+	return nil
+}
+
+func subvolDisableQuota(path string) error {
+	dir, err := openDir(path)
+	if err != nil {
+		return err
+	}
+	defer closeDir(dir)
+
+	var args C.struct_btrfs_ioctl_quota_ctl_args
+	args.cmd = C.BTRFS_QUOTA_CTL_DISABLE
+	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, getDirFd(dir), C.BTRFS_IOC_QUOTA_CTL,
+		uintptr(unsafe.Pointer(&args)))
+	if errno != 0 {
+		return fmt.Errorf("Failed to disable btrfs quota for %s: %v", dir, errno.Error())
+	}
+
+	return nil
+}
+
+func subvolRescanQuota(path string) error {
+	dir, err := openDir(path)
+	if err != nil {
+		return err
+	}
+	defer closeDir(dir)
+
+	var args C.struct_btrfs_ioctl_quota_rescan_args
+	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, getDirFd(dir), C.BTRFS_IOC_QUOTA_RESCAN_WAIT,
+		uintptr(unsafe.Pointer(&args)))
+	if errno != 0 {
+		return fmt.Errorf("Failed to rescan btrfs quota for %s: %v", dir, errno.Error())
+	}
+
+	return nil
+}
+
+func subvolLimitQgroup(path string, size uint64) error {
+	dir, err := openDir(path)
+	if err != nil {
+		return err
+	}
+	defer closeDir(dir)
+
+	var args C.struct_btrfs_ioctl_qgroup_limit_args
+	args.lim.max_referenced = C.__u64(size)
+	args.lim.flags = C.BTRFS_QGROUP_LIMIT_MAX_RFER
+	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, getDirFd(dir), C.BTRFS_IOC_QGROUP_LIMIT,
+		uintptr(unsafe.Pointer(&args)))
+	if errno != 0 {
+		return fmt.Errorf("Failed to limit qgroup for %s: %v", dir, errno.Error())
+	}
+
+	return nil
+}
+
+func (d *Driver) subvolumesDir() string {
+	return path.Join(d.home, "subvolumes")
+}
+
+func (d *Driver) subvolumesDirID(id string) string {
+	return path.Join(d.subvolumesDir(), id)
+}
+
+// CreateReadWrite creates a layer that is writable for use as a container
+// file system.
+func (d *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	return d.Create(id, parent, mountLabel, storageOpt)
+}
+
+// Create the filesystem with given id.
+func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]string) error {
+	subvolumes := path.Join(d.home, "subvolumes")
+	rootUID, rootGID, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		return err
+	}
+	if err := idtools.MkdirAllAs(subvolumes, 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+	if parent == "" {
+		if err := subvolCreate(subvolumes, id); err != nil {
+			return err
+		}
+	} else {
+		parentDir := d.subvolumesDirID(parent)
+		st, err := os.Stat(parentDir)
+		if err != nil {
+			return err
+		}
+		if !st.IsDir() {
+			return fmt.Errorf("%s: not a directory", parentDir)
+		}
+		if err := subvolSnapshot(parentDir, subvolumes, id); err != nil {
+			return err
+		}
+	}
+
+	if _, ok := storageOpt["size"]; ok {
+		driver := &Driver{}
+		if err := d.parseStorageOpt(storageOpt, driver); err != nil {
+			return err
+		}
+		if err := d.setStorageSize(path.Join(subvolumes, id), driver); err != nil {
+			return err
+		}
+	}
+
+	// if we have a remapped root (user namespaces enabled), change the created snapshot
+	// dir ownership to match
+	if rootUID != 0 || rootGID != 0 {
+		if err := os.Chown(path.Join(subvolumes, id), rootUID, rootGID); err != nil {
+			return err
+		}
+	}
+
+	return label.Relabel(path.Join(subvolumes, id), mountLabel, false)
+}
+
+// Parse btrfs storage options
+func (d *Driver) parseStorageOpt(storageOpt map[string]string, driver *Driver) error {
+	// Read size to change the subvolume disk quota per container
+	for key, val := range storageOpt {
+		key := strings.ToLower(key)
+		switch key {
+		case "size":
+			size, err := units.RAMInBytes(val)
+			if err != nil {
+				return err
+			}
+			driver.options.size = uint64(size)
+		default:
+			return fmt.Errorf("Unknown option %s", key)
+		}
+	}
+
+	return nil
+}
+
+// Set btrfs storage size
+func (d *Driver) setStorageSize(dir string, driver *Driver) error {
+	if driver.options.size <= 0 {
+		return fmt.Errorf("btrfs: invalid storage size: %s", units.HumanSize(float64(driver.options.size)))
+	}
+	if d.options.minSpace > 0 && driver.options.size < d.options.minSpace {
+		return fmt.Errorf("btrfs: storage size cannot be less than %s", units.HumanSize(float64(d.options.minSpace)))
+	}
+
+	if !quotaEnabled {
+		if err := subvolEnableQuota(d.home); err != nil {
+			return err
+		}
+		quotaEnabled = true
+	}
+
+	if err := subvolLimitQgroup(dir, driver.options.size); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Remove the filesystem with given id.
+func (d *Driver) Remove(id string) error {
+	dir := d.subvolumesDirID(id)
+	if _, err := os.Stat(dir); err != nil {
+		return err
+	}
+	if err := subvolDelete(d.subvolumesDir(), id); err != nil {
+		return err
+	}
+	if err := os.RemoveAll(dir); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	if err := subvolRescanQuota(d.home); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Get the requested filesystem id.
+func (d *Driver) Get(id, mountLabel string) (string, error) {
+	dir := d.subvolumesDirID(id)
+	st, err := os.Stat(dir)
+	if err != nil {
+		return "", err
+	}
+
+	if !st.IsDir() {
+		return "", fmt.Errorf("%s: not a directory", dir)
+	}
+
+	return dir, nil
+}
+
+// Put is not implemented for BTRFS as there is no cleanup required for the id.
+func (d *Driver) Put(id string) error {
+	// Get() creates no runtime resources (like e.g. mounts)
+	// so this doesn't need to do anything.
+	return nil
+}
+
+// Exists checks if the id exists in the filesystem.
+func (d *Driver) Exists(id string) bool {
+	dir := d.subvolumesDirID(id)
+	_, err := os.Stat(dir)
+	return err == nil
+}

vendor/src/github.com/containers/storage/drivers/btrfs/dummy_unsupported.go

@@ -0,0 +1,3 @@
+// +build !linux !cgo
+
+package btrfs

vendor/src/github.com/containers/storage/drivers/btrfs/version.go

@@ -0,0 +1,26 @@
+// +build linux,!btrfs_noversion
+
+package btrfs
+
+/*
+#include <btrfs/version.h>
+
+// around version 3.16, they did not define lib version yet
+#ifndef BTRFS_LIB_VERSION
+#define BTRFS_LIB_VERSION -1
+#endif
+
+// upstream had removed it, but now it will be coming back
+#ifndef BTRFS_BUILD_VERSION
+#define BTRFS_BUILD_VERSION "-"
+#endif
+*/
+import "C"
+
+func btrfsBuildVersion() string {
+	return string(C.BTRFS_BUILD_VERSION)
+}
+
+func btrfsLibVersion() int {
+	return int(C.BTRFS_LIB_VERSION)
+}

vendor/src/github.com/containers/storage/drivers/btrfs/version_none.go

@@ -0,0 +1,14 @@
+// +build linux,btrfs_noversion
+
+package btrfs
+
+// TODO(vbatts) remove this work-around once supported linux distros are on
+// btrfs utilities of >= 3.16.1
+
+func btrfsBuildVersion() string {
+	return "-"
+}
+
+func btrfsLibVersion() int {
+	return -1
+}

vendor/src/github.com/containers/storage/drivers/counter.go

@@ -0,0 +1,67 @@
+package graphdriver
+
+import "sync"
+
+type minfo struct {
+	check bool
+	count int
+}
+
+// RefCounter is a generic counter for use by graphdriver Get/Put calls
+type RefCounter struct {
+	counts  map[string]*minfo
+	mu      sync.Mutex
+	checker Checker
+}
+
+// NewRefCounter returns a new RefCounter
+func NewRefCounter(c Checker) *RefCounter {
+	return &RefCounter{
+		checker: c,
+		counts:  make(map[string]*minfo),
+	}
+}
+
+// Increment increaes the ref count for the given id and returns the current count
+func (c *RefCounter) Increment(path string) int {
+	c.mu.Lock()
+	m := c.counts[path]
+	if m == nil {
+		m = &minfo{}
+		c.counts[path] = m
+	}
+	// if we are checking this path for the first time check to make sure
+	// if it was already mounted on the system and make sure we have a correct ref
+	// count if it is mounted as it is in use.
+	if !m.check {
+		m.check = true
+		if c.checker.IsMounted(path) {
+			m.count++
+		}
+	}
+	m.count++
+	c.mu.Unlock()
+	return m.count
+}
+
+// Decrement decreases the ref count for the given id and returns the current count
+func (c *RefCounter) Decrement(path string) int {
+	c.mu.Lock()
+	m := c.counts[path]
+	if m == nil {
+		m = &minfo{}
+		c.counts[path] = m
+	}
+	// if we are checking this path for the first time check to make sure
+	// if it was already mounted on the system and make sure we have a correct ref
+	// count if it is mounted as it is in use.
+	if !m.check {
+		m.check = true
+		if c.checker.IsMounted(path) {
+			m.count++
+		}
+	}
+	m.count--
+	c.mu.Unlock()
+	return m.count
+}

vendor/src/github.com/containers/storage/drivers/devmapper/devmapper_doc.go

@@ -0,0 +1,106 @@
+package devmapper
+
+// Definition of struct dm_task and sub structures (from lvm2)
+//
+// struct dm_ioctl {
+// 	/*
+// 	 * The version number is made up of three parts:
+// 	 * major - no backward or forward compatibility,
+// 	 * minor - only backwards compatible,
+// 	 * patch - both backwards and forwards compatible.
+// 	 *
+// 	 * All clients of the ioctl interface should fill in the
+// 	 * version number of the interface that they were
+// 	 * compiled with.
+// 	 *
+// 	 * All recognized ioctl commands (ie. those that don't
+// 	 * return -ENOTTY) fill out this field, even if the
+// 	 * command failed.
+// 	 */
+// 	uint32_t version[3];	/* in/out */
+// 	uint32_t data_size;	/* total size of data passed in
+// 				 * including this struct */
+
+// 	uint32_t data_start;	/* offset to start of data
+// 				 * relative to start of this struct */
+
+// 	uint32_t target_count;	/* in/out */
+// 	int32_t open_count;	/* out */
+// 	uint32_t flags;		/* in/out */
+
+// 	/*
+// 	 * event_nr holds either the event number (input and output) or the
+// 	 * udev cookie value (input only).
+// 	 * The DM_DEV_WAIT ioctl takes an event number as input.
+// 	 * The DM_SUSPEND, DM_DEV_REMOVE and DM_DEV_RENAME ioctls
+// 	 * use the field as a cookie to return in the DM_COOKIE
+// 	 * variable with the uevents they issue.
+// 	 * For output, the ioctls return the event number, not the cookie.
+// 	 */
+// 	uint32_t event_nr;      	/* in/out */
+// 	uint32_t padding;
+
+// 	uint64_t dev;		/* in/out */
+
+// 	char name[DM_NAME_LEN];	/* device name */
+// 	char uuid[DM_UUID_LEN];	/* unique identifier for
+// 				 * the block device */
+// 	char data[7];		/* padding or data */
+// };
+
+// struct target {
+// 	uint64_t start;
+// 	uint64_t length;
+// 	char *type;
+// 	char *params;
+
+// 	struct target *next;
+// };
+
+// typedef enum {
+// 	DM_ADD_NODE_ON_RESUME, /* add /dev/mapper node with dmsetup resume */
+// 	DM_ADD_NODE_ON_CREATE  /* add /dev/mapper node with dmsetup create */
+// } dm_add_node_t;
+
+// struct dm_task {
+// 	int type;
+// 	char *dev_name;
+// 	char *mangled_dev_name;
+
+// 	struct target *head, *tail;
+
+// 	int read_only;
+// 	uint32_t event_nr;
+// 	int major;
+// 	int minor;
+// 	int allow_default_major_fallback;
+// 	uid_t uid;
+// 	gid_t gid;
+// 	mode_t mode;
+// 	uint32_t read_ahead;
+// 	uint32_t read_ahead_flags;
+// 	union {
+// 		struct dm_ioctl *v4;
+// 	} dmi;
+// 	char *newname;
+// 	char *message;
+// 	char *geometry;
+// 	uint64_t sector;
+// 	int no_flush;
+// 	int no_open_count;
+// 	int skip_lockfs;
+// 	int query_inactive_table;
+// 	int suppress_identical_reload;
+// 	dm_add_node_t add_node;
+// 	uint64_t existing_table_size;
+// 	int cookie_set;
+// 	int new_uuid;
+// 	int secure_data;
+// 	int retry_remove;
+// 	int enable_checks;
+// 	int expected_errno;
+
+// 	char *uuid;
+// 	char *mangled_uuid;
+// };
+//

vendor/src/github.com/containers/storage/drivers/devmapper/driver.go

@@ -0,0 +1,226 @@
+// +build linux
+
+package devmapper
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"strconv"
+
+	"github.com/Sirupsen/logrus"
+
+	"github.com/containers/storage/drivers"
+	"github.com/containers/storage/pkg/devicemapper"
+	"github.com/containers/storage/pkg/idtools"
+	"github.com/containers/storage/pkg/mount"
+	"github.com/docker/go-units"
+)
+
+func init() {
+	graphdriver.Register("devicemapper", Init)
+}
+
+// Driver contains the device set mounted and the home directory
+type Driver struct {
+	*DeviceSet
+	home    string
+	uidMaps []idtools.IDMap
+	gidMaps []idtools.IDMap
+	ctr     *graphdriver.RefCounter
+}
+
+// Init creates a driver with the given home and the set of options.
+func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
+	deviceSet, err := NewDeviceSet(home, true, options, uidMaps, gidMaps)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := mount.MakePrivate(home); err != nil {
+		return nil, err
+	}
+
+	d := &Driver{
+		DeviceSet: deviceSet,
+		home:      home,
+		uidMaps:   uidMaps,
+		gidMaps:   gidMaps,
+		ctr:       graphdriver.NewRefCounter(graphdriver.NewDefaultChecker()),
+	}
+
+	return graphdriver.NewNaiveDiffDriver(d, uidMaps, gidMaps), nil
+}
+
+func (d *Driver) String() string {
+	return "devicemapper"
+}
+
+// Status returns the status about the driver in a printable format.
+// Information returned contains Pool Name, Data File, Metadata file, disk usage by
+// the data and metadata, etc.
+func (d *Driver) Status() [][2]string {
+	s := d.DeviceSet.Status()
+
+	status := [][2]string{
+		{"Pool Name", s.PoolName},
+		{"Pool Blocksize", fmt.Sprintf("%s", units.HumanSize(float64(s.SectorSize)))},
+		{"Base Device Size", fmt.Sprintf("%s", units.HumanSize(float64(s.BaseDeviceSize)))},
+		{"Backing Filesystem", s.BaseDeviceFS},
+		{"Data file", s.DataFile},
+		{"Metadata file", s.MetadataFile},
+		{"Data Space Used", fmt.Sprintf("%s", units.HumanSize(float64(s.Data.Used)))},
+		{"Data Space Total", fmt.Sprintf("%s", units.HumanSize(float64(s.Data.Total)))},
+		{"Data Space Available", fmt.Sprintf("%s", units.HumanSize(float64(s.Data.Available)))},
+		{"Metadata Space Used", fmt.Sprintf("%s", units.HumanSize(float64(s.Metadata.Used)))},
+		{"Metadata Space Total", fmt.Sprintf("%s", units.HumanSize(float64(s.Metadata.Total)))},
+		{"Metadata Space Available", fmt.Sprintf("%s", units.HumanSize(float64(s.Metadata.Available)))},
+		{"Thin Pool Minimum Free Space", fmt.Sprintf("%s", units.HumanSize(float64(s.MinFreeSpace)))},
+		{"Udev Sync Supported", fmt.Sprintf("%v", s.UdevSyncSupported)},
+		{"Deferred Removal Enabled", fmt.Sprintf("%v", s.DeferredRemoveEnabled)},
+		{"Deferred Deletion Enabled", fmt.Sprintf("%v", s.DeferredDeleteEnabled)},
+		{"Deferred Deleted Device Count", fmt.Sprintf("%v", s.DeferredDeletedDeviceCount)},
+	}
+	if len(s.DataLoopback) > 0 {
+		status = append(status, [2]string{"Data loop file", s.DataLoopback})
+	}
+	if len(s.MetadataLoopback) > 0 {
+		status = append(status, [2]string{"Metadata loop file", s.MetadataLoopback})
+	}
+	if vStr, err := devicemapper.GetLibraryVersion(); err == nil {
+		status = append(status, [2]string{"Library Version", vStr})
+	}
+	return status
+}
+
+// GetMetadata returns a map of information about the device.
+func (d *Driver) GetMetadata(id string) (map[string]string, error) {
+	m, err := d.DeviceSet.exportDeviceMetadata(id)
+
+	if err != nil {
+		return nil, err
+	}
+
+	metadata := make(map[string]string)
+	metadata["DeviceId"] = strconv.Itoa(m.deviceID)
+	metadata["DeviceSize"] = strconv.FormatUint(m.deviceSize, 10)
+	metadata["DeviceName"] = m.deviceName
+	return metadata, nil
+}
+
+// Cleanup unmounts a device.
+func (d *Driver) Cleanup() error {
+	err := d.DeviceSet.Shutdown(d.home)
+
+	if err2 := mount.Unmount(d.home); err == nil {
+		err = err2
+	}
+
+	return err
+}
+
+// CreateReadWrite creates a layer that is writable for use as a container
+// file system.
+func (d *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	return d.Create(id, parent, mountLabel, storageOpt)
+}
+
+// Create adds a device with a given id and the parent.
+func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]string) error {
+	if err := d.DeviceSet.AddDevice(id, parent, storageOpt); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Remove removes a device with a given id, unmounts the filesystem.
+func (d *Driver) Remove(id string) error {
+	if !d.DeviceSet.HasDevice(id) {
+		// Consider removing a non-existing device a no-op
+		// This is useful to be able to progress on container removal
+		// if the underlying device has gone away due to earlier errors
+		return nil
+	}
+
+	// This assumes the device has been properly Get/Put:ed and thus is unmounted
+	if err := d.DeviceSet.DeleteDevice(id, false); err != nil {
+		return err
+	}
+
+	mp := path.Join(d.home, "mnt", id)
+	if err := os.RemoveAll(mp); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+
+	return nil
+}
+
+// Get mounts a device with given id into the root filesystem
+func (d *Driver) Get(id, mountLabel string) (string, error) {
+	mp := path.Join(d.home, "mnt", id)
+	rootFs := path.Join(mp, "rootfs")
+	if count := d.ctr.Increment(mp); count > 1 {
+		return rootFs, nil
+	}
+
+	uid, gid, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		d.ctr.Decrement(mp)
+		return "", err
+	}
+
+	// Create the target directories if they don't exist
+	if err := idtools.MkdirAllAs(path.Join(d.home, "mnt"), 0755, uid, gid); err != nil && !os.IsExist(err) {
+		d.ctr.Decrement(mp)
+		return "", err
+	}
+	if err := idtools.MkdirAs(mp, 0755, uid, gid); err != nil && !os.IsExist(err) {
+		d.ctr.Decrement(mp)
+		return "", err
+	}
+
+	// Mount the device
+	if err := d.DeviceSet.MountDevice(id, mp, mountLabel); err != nil {
+		d.ctr.Decrement(mp)
+		return "", err
+	}
+
+	if err := idtools.MkdirAllAs(rootFs, 0755, uid, gid); err != nil && !os.IsExist(err) {
+		d.ctr.Decrement(mp)
+		d.DeviceSet.UnmountDevice(id, mp)
+		return "", err
+	}
+
+	idFile := path.Join(mp, "id")
+	if _, err := os.Stat(idFile); err != nil && os.IsNotExist(err) {
+		// Create an "id" file with the container/image id in it to help reconstruct this in case
+		// of later problems
+		if err := ioutil.WriteFile(idFile, []byte(id), 0600); err != nil {
+			d.ctr.Decrement(mp)
+			d.DeviceSet.UnmountDevice(id, mp)
+			return "", err
+		}
+	}
+
+	return rootFs, nil
+}
+
+// Put unmounts a device and removes it.
+func (d *Driver) Put(id string) error {
+	mp := path.Join(d.home, "mnt", id)
+	if count := d.ctr.Decrement(mp); count > 0 {
+		return nil
+	}
+	err := d.DeviceSet.UnmountDevice(id, mp)
+	if err != nil {
+		logrus.Errorf("devmapper: Error unmounting device %s: %s", id, err)
+	}
+	return err
+}
+
+// Exists checks to see if the device exists.
+func (d *Driver) Exists(id string) bool {
+	return d.DeviceSet.HasDevice(id)
+}

vendor/src/github.com/containers/storage/drivers/devmapper/mount.go

@@ -0,0 +1,89 @@
+// +build linux
+
+package devmapper
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"path/filepath"
+	"syscall"
+)
+
+// FIXME: this is copy-pasted from the aufs driver.
+// It should be moved into the core.
+
+// Mounted returns true if a mount point exists.
+func Mounted(mountpoint string) (bool, error) {
+	mntpoint, err := os.Stat(mountpoint)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return false, nil
+		}
+		return false, err
+	}
+	parent, err := os.Stat(filepath.Join(mountpoint, ".."))
+	if err != nil {
+		return false, err
+	}
+	mntpointSt := mntpoint.Sys().(*syscall.Stat_t)
+	parentSt := parent.Sys().(*syscall.Stat_t)
+	return mntpointSt.Dev != parentSt.Dev, nil
+}
+
+type probeData struct {
+	fsName string
+	magic  string
+	offset uint64
+}
+
+// ProbeFsType returns the filesystem name for the given device id.
+func ProbeFsType(device string) (string, error) {
+	probes := []probeData{
+		{"btrfs", "_BHRfS_M", 0x10040},
+		{"ext4", "\123\357", 0x438},
+		{"xfs", "XFSB", 0},
+	}
+
+	maxLen := uint64(0)
+	for _, p := range probes {
+		l := p.offset + uint64(len(p.magic))
+		if l > maxLen {
+			maxLen = l
+		}
+	}
+
+	file, err := os.Open(device)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+
+	buffer := make([]byte, maxLen)
+	l, err := file.Read(buffer)
+	if err != nil {
+		return "", err
+	}
+
+	if uint64(l) != maxLen {
+		return "", fmt.Errorf("devmapper: unable to detect filesystem type of %s, short read", device)
+	}
+
+	for _, p := range probes {
+		if bytes.Equal([]byte(p.magic), buffer[p.offset:p.offset+uint64(len(p.magic))]) {
+			return p.fsName, nil
+		}
+	}
+
+	return "", fmt.Errorf("devmapper: Unknown filesystem type on %s", device)
+}
+
+func joinMountOptions(a, b string) string {
+	if a == "" {
+		return b
+	}
+	if b == "" {
+		return a
+	}
+	return a + "," + b
+}

vendor/src/github.com/containers/storage/drivers/driver.go

@@ -0,0 +1,243 @@
+package graphdriver
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/vbatts/tar-split/tar/storage"
+
+	"github.com/containers/storage/pkg/archive"
+	"github.com/containers/storage/pkg/idtools"
+)
+
+// FsMagic unsigned id of the filesystem in use.
+type FsMagic uint32
+
+const (
+	// FsMagicUnsupported is a predefined constant value other than a valid filesystem id.
+	FsMagicUnsupported = FsMagic(0x00000000)
+)
+
+var (
+	// All registered drivers
+	drivers map[string]InitFunc
+
+	// ErrNotSupported returned when driver is not supported.
+	ErrNotSupported = errors.New("driver not supported")
+	// ErrPrerequisites retuned when driver does not meet prerequisites.
+	ErrPrerequisites = errors.New("prerequisites for driver not satisfied (wrong filesystem?)")
+	// ErrIncompatibleFS returned when file system is not supported.
+	ErrIncompatibleFS = fmt.Errorf("backing file system is unsupported for this graph driver")
+)
+
+// InitFunc initializes the storage driver.
+type InitFunc func(root string, options []string, uidMaps, gidMaps []idtools.IDMap) (Driver, error)
+
+// ProtoDriver defines the basic capabilities of a driver.
+// This interface exists solely to be a minimum set of methods
+// for client code which choose not to implement the entire Driver
+// interface and use the NaiveDiffDriver wrapper constructor.
+//
+// Use of ProtoDriver directly by client code is not recommended.
+type ProtoDriver interface {
+	// String returns a string representation of this driver.
+	String() string
+	// CreateReadWrite creates a new, empty filesystem layer that is ready
+	// to be used as the storage for a container.
+	CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error
+	// Create creates a new, empty, filesystem layer with the
+	// specified id and parent and mountLabel. Parent and mountLabel may be "".
+	Create(id, parent, mountLabel string, storageOpt map[string]string) error
+	// Remove attempts to remove the filesystem layer with this id.
+	Remove(id string) error
+	// Get returns the mountpoint for the layered filesystem referred
+	// to by this id. You can optionally specify a mountLabel or "".
+	// Returns the absolute path to the mounted layered filesystem.
+	Get(id, mountLabel string) (dir string, err error)
+	// Put releases the system resources for the specified id,
+	// e.g, unmounting layered filesystem.
+	Put(id string) error
+	// Exists returns whether a filesystem layer with the specified
+	// ID exists on this driver.
+	Exists(id string) bool
+	// Status returns a set of key-value pairs which give low
+	// level diagnostic status about this driver.
+	Status() [][2]string
+	// Returns a set of key-value pairs which give low level information
+	// about the image/container driver is managing.
+	GetMetadata(id string) (map[string]string, error)
+	// Cleanup performs necessary tasks to release resources
+	// held by the driver, e.g., unmounting all layered filesystems
+	// known to this driver.
+	Cleanup() error
+}
+
+// Driver is the interface for layered/snapshot file system drivers.
+type Driver interface {
+	ProtoDriver
+	// Diff produces an archive of the changes between the specified
+	// layer and its parent layer which may be "".
+	Diff(id, parent string) (archive.Archive, error)
+	// Changes produces a list of changes between the specified layer
+	// and its parent layer. If parent is "", then all changes will be ADD changes.
+	Changes(id, parent string) ([]archive.Change, error)
+	// ApplyDiff extracts the changeset from the given diff into the
+	// layer with the specified id and parent, returning the size of the
+	// new layer in bytes.
+	// The archive.Reader must be an uncompressed stream.
+	ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error)
+	// DiffSize calculates the changes between the specified id
+	// and its parent and returns the size in bytes of the changes
+	// relative to its base filesystem directory.
+	DiffSize(id, parent string) (size int64, err error)
+}
+
+// DiffGetterDriver is the interface for layered file system drivers that
+// provide a specialized function for getting file contents for tar-split.
+type DiffGetterDriver interface {
+	Driver
+	// DiffGetter returns an interface to efficiently retrieve the contents
+	// of files in a layer.
+	DiffGetter(id string) (FileGetCloser, error)
+}
+
+// FileGetCloser extends the storage.FileGetter interface with a Close method
+// for cleaning up.
+type FileGetCloser interface {
+	storage.FileGetter
+	// Close cleans up any resources associated with the FileGetCloser.
+	Close() error
+}
+
+// Checker makes checks on specified filesystems.
+type Checker interface {
+	// IsMounted returns true if the provided path is mounted for the specific checker
+	IsMounted(path string) bool
+}
+
+func init() {
+	drivers = make(map[string]InitFunc)
+}
+
+// Register registers an InitFunc for the driver.
+func Register(name string, initFunc InitFunc) error {
+	if _, exists := drivers[name]; exists {
+		return fmt.Errorf("Name already registered %s", name)
+	}
+	drivers[name] = initFunc
+
+	return nil
+}
+
+// GetDriver initializes and returns the registered driver
+func GetDriver(name, home string, options []string, uidMaps, gidMaps []idtools.IDMap) (Driver, error) {
+	if initFunc, exists := drivers[name]; exists {
+		return initFunc(filepath.Join(home, name), options, uidMaps, gidMaps)
+	}
+	if pluginDriver, err := lookupPlugin(name, home, options); err == nil {
+		return pluginDriver, nil
+	}
+	logrus.Errorf("Failed to GetDriver graph %s %s", name, home)
+	return nil, ErrNotSupported
+}
+
+// getBuiltinDriver initializes and returns the registered driver, but does not try to load from plugins
+func getBuiltinDriver(name, home string, options []string, uidMaps, gidMaps []idtools.IDMap) (Driver, error) {
+	if initFunc, exists := drivers[name]; exists {
+		return initFunc(filepath.Join(home, name), options, uidMaps, gidMaps)
+	}
+	logrus.Errorf("Failed to built-in GetDriver graph %s %s", name, home)
+	return nil, ErrNotSupported
+}
+
+// New creates the driver and initializes it at the specified root.
+func New(root string, name string, options []string, uidMaps, gidMaps []idtools.IDMap) (Driver, error) {
+	if name != "" {
+		logrus.Debugf("[graphdriver] trying provided driver %q", name) // so the logs show specified driver
+		return GetDriver(name, root, options, uidMaps, gidMaps)
+	}
+
+	// Guess for prior driver
+	driversMap := scanPriorDrivers(root)
+	for _, name := range priority {
+		if name == "vfs" {
+			// don't use vfs even if there is state present.
+			continue
+		}
+		if _, prior := driversMap[name]; prior {
+			// of the state found from prior drivers, check in order of our priority
+			// which we would prefer
+			driver, err := getBuiltinDriver(name, root, options, uidMaps, gidMaps)
+			if err != nil {
+				// unlike below, we will return error here, because there is prior
+				// state, and now it is no longer supported/prereq/compatible, so
+				// something changed and needs attention. Otherwise the daemon's
+				// images would just "disappear".
+				logrus.Errorf("[graphdriver] prior storage driver %q failed: %s", name, err)
+				return nil, err
+			}
+
+			// abort starting when there are other prior configured drivers
+			// to ensure the user explicitly selects the driver to load
+			if len(driversMap)-1 > 0 {
+				var driversSlice []string
+				for name := range driversMap {
+					driversSlice = append(driversSlice, name)
+				}
+
+				return nil, fmt.Errorf("%q contains several valid graphdrivers: %s; Please cleanup or explicitly choose storage driver (-s <DRIVER>)", root, strings.Join(driversSlice, ", "))
+			}
+
+			logrus.Infof("[graphdriver] using prior storage driver %q", name)
+			return driver, nil
+		}
+	}
+
+	// Check for priority drivers first
+	for _, name := range priority {
+		driver, err := getBuiltinDriver(name, root, options, uidMaps, gidMaps)
+		if err != nil {
+			if isDriverNotSupported(err) {
+				continue
+			}
+			return nil, err
+		}
+		return driver, nil
+	}
+
+	// Check all registered drivers if no priority driver is found
+	for name, initFunc := range drivers {
+		driver, err := initFunc(filepath.Join(root, name), options, uidMaps, gidMaps)
+		if err != nil {
+			if isDriverNotSupported(err) {
+				continue
+			}
+			return nil, err
+		}
+		return driver, nil
+	}
+	return nil, fmt.Errorf("No supported storage backend found")
+}
+
+// isDriverNotSupported returns true if the error initializing
+// the graph driver is a non-supported error.
+func isDriverNotSupported(err error) bool {
+	return err == ErrNotSupported || err == ErrPrerequisites || err == ErrIncompatibleFS
+}
+
+// scanPriorDrivers returns an un-ordered scan of directories of prior storage drivers
+func scanPriorDrivers(root string) map[string]bool {
+	driversMap := make(map[string]bool)
+
+	for driver := range drivers {
+		p := filepath.Join(root, driver)
+		if _, err := os.Stat(p); err == nil && driver != "vfs" {
+			driversMap[driver] = true
+		}
+	}
+	return driversMap
+}

vendor/src/github.com/containers/storage/drivers/driver_freebsd.go

@@ -0,0 +1,19 @@
+package graphdriver
+
+import "syscall"
+
+var (
+	// Slice of drivers that should be used in an order
+	priority = []string{
+		"zfs",
+	}
+)
+
+// Mounted checks if the given path is mounted as the fs type
+func Mounted(fsType FsMagic, mountPath string) (bool, error) {
+	var buf syscall.Statfs_t
+	if err := syscall.Statfs(mountPath, &buf); err != nil {
+		return false, err
+	}
+	return FsMagic(buf.Type) == fsType, nil
+}

vendor/src/github.com/containers/storage/drivers/driver_linux.go

@@ -0,0 +1,133 @@
+// +build linux
+
+package graphdriver
+
+import (
+	"path/filepath"
+	"syscall"
+
+	"github.com/containers/storage/pkg/mount"
+)
+
+const (
+	// FsMagicAufs filesystem id for Aufs
+	FsMagicAufs = FsMagic(0x61756673)
+	// FsMagicBtrfs filesystem id for Btrfs
+	FsMagicBtrfs = FsMagic(0x9123683E)
+	// FsMagicCramfs filesystem id for Cramfs
+	FsMagicCramfs = FsMagic(0x28cd3d45)
+	// FsMagicEcryptfs filesystem id for eCryptfs
+	FsMagicEcryptfs = FsMagic(0xf15f)
+	// FsMagicExtfs filesystem id for Extfs
+	FsMagicExtfs = FsMagic(0x0000EF53)
+	// FsMagicF2fs filesystem id for F2fs
+	FsMagicF2fs = FsMagic(0xF2F52010)
+	// FsMagicGPFS filesystem id for GPFS
+	FsMagicGPFS = FsMagic(0x47504653)
+	// FsMagicJffs2Fs filesystem if for Jffs2Fs
+	FsMagicJffs2Fs = FsMagic(0x000072b6)
+	// FsMagicJfs filesystem id for Jfs
+	FsMagicJfs = FsMagic(0x3153464a)
+	// FsMagicNfsFs filesystem id for NfsFs
+	FsMagicNfsFs = FsMagic(0x00006969)
+	// FsMagicRAMFs filesystem id for RamFs
+	FsMagicRAMFs = FsMagic(0x858458f6)
+	// FsMagicReiserFs filesystem id for ReiserFs
+	FsMagicReiserFs = FsMagic(0x52654973)
+	// FsMagicSmbFs filesystem id for SmbFs
+	FsMagicSmbFs = FsMagic(0x0000517B)
+	// FsMagicSquashFs filesystem id for SquashFs
+	FsMagicSquashFs = FsMagic(0x73717368)
+	// FsMagicTmpFs filesystem id for TmpFs
+	FsMagicTmpFs = FsMagic(0x01021994)
+	// FsMagicVxFS filesystem id for VxFs
+	FsMagicVxFS = FsMagic(0xa501fcf5)
+	// FsMagicXfs filesystem id for Xfs
+	FsMagicXfs = FsMagic(0x58465342)
+	// FsMagicZfs filesystem id for Zfs
+	FsMagicZfs = FsMagic(0x2fc12fc1)
+	// FsMagicOverlay filesystem id for overlay
+	FsMagicOverlay = FsMagic(0x794C7630)
+)
+
+var (
+	// Slice of drivers that should be used in an order
+	priority = []string{
+		"aufs",
+		"btrfs",
+		"zfs",
+		"devicemapper",
+		"overlay",
+		"vfs",
+	}
+
+	// FsNames maps filesystem id to name of the filesystem.
+	FsNames = map[FsMagic]string{
+		FsMagicAufs:        "aufs",
+		FsMagicBtrfs:       "btrfs",
+		FsMagicCramfs:      "cramfs",
+		FsMagicExtfs:       "extfs",
+		FsMagicF2fs:        "f2fs",
+		FsMagicGPFS:        "gpfs",
+		FsMagicJffs2Fs:     "jffs2",
+		FsMagicJfs:         "jfs",
+		FsMagicNfsFs:       "nfs",
+		FsMagicRAMFs:       "ramfs",
+		FsMagicReiserFs:    "reiserfs",
+		FsMagicSmbFs:       "smb",
+		FsMagicSquashFs:    "squashfs",
+		FsMagicTmpFs:       "tmpfs",
+		FsMagicUnsupported: "unsupported",
+		FsMagicVxFS:        "vxfs",
+		FsMagicXfs:         "xfs",
+		FsMagicZfs:         "zfs",
+	}
+)
+
+// GetFSMagic returns the filesystem id given the path.
+func GetFSMagic(rootpath string) (FsMagic, error) {
+	var buf syscall.Statfs_t
+	if err := syscall.Statfs(filepath.Dir(rootpath), &buf); err != nil {
+		return 0, err
+	}
+	return FsMagic(buf.Type), nil
+}
+
+// NewFsChecker returns a checker configured for the provied FsMagic
+func NewFsChecker(t FsMagic) Checker {
+	return &fsChecker{
+		t: t,
+	}
+}
+
+type fsChecker struct {
+	t FsMagic
+}
+
+func (c *fsChecker) IsMounted(path string) bool {
+	m, _ := Mounted(c.t, path)
+	return m
+}
+
+// NewDefaultChecker returns a check that parses /proc/mountinfo to check
+// if the specified path is mounted.
+func NewDefaultChecker() Checker {
+	return &defaultChecker{}
+}
+
+type defaultChecker struct {
+}
+
+func (c *defaultChecker) IsMounted(path string) bool {
+	m, _ := mount.Mounted(path)
+	return m
+}
+
+// Mounted checks if the given path is mounted as the fs type
+func Mounted(fsType FsMagic, mountPath string) (bool, error) {
+	var buf syscall.Statfs_t
+	if err := syscall.Statfs(mountPath, &buf); err != nil {
+		return false, err
+	}
+	return FsMagic(buf.Type) == fsType, nil
+}

vendor/src/github.com/containers/storage/drivers/driver_solaris.go

@@ -0,0 +1,65 @@
+// +build solaris,cgo
+
+package graphdriver
+
+/*
+#include <sys/statvfs.h>
+#include <stdlib.h>
+
+static inline struct statvfs *getstatfs(char *s) {
+        struct statvfs *buf;
+        int err;
+        buf = (struct statvfs *)malloc(sizeof(struct statvfs));
+        err = statvfs(s, buf);
+        return buf;
+}
+*/
+import "C"
+import (
+	"path/filepath"
+	"unsafe"
+
+	log "github.com/Sirupsen/logrus"
+)
+
+const (
+	// FsMagicZfs filesystem id for Zfs
+	FsMagicZfs = FsMagic(0x2fc12fc1)
+)
+
+var (
+	// Slice of drivers that should be used in an order
+	priority = []string{
+		"zfs",
+	}
+
+	// FsNames maps filesystem id to name of the filesystem.
+	FsNames = map[FsMagic]string{
+		FsMagicZfs: "zfs",
+	}
+)
+
+// GetFSMagic returns the filesystem id given the path.
+func GetFSMagic(rootpath string) (FsMagic, error) {
+	return 0, nil
+}
+
+// Mounted checks if the given path is mounted as the fs type
+//Solaris supports only ZFS for now
+func Mounted(fsType FsMagic, mountPath string) (bool, error) {
+
+	cs := C.CString(filepath.Dir(mountPath))
+	buf := C.getstatfs(cs)
+
+	// on Solaris buf.f_basetype contains ['z', 'f', 's', 0 ... ]
+	if (buf.f_basetype[0] != 122) || (buf.f_basetype[1] != 102) || (buf.f_basetype[2] != 115) ||
+		(buf.f_basetype[3] != 0) {
+		log.Debugf("[zfs] no zfs dataset found for rootdir '%s'", mountPath)
+		C.free(unsafe.Pointer(buf))
+		return false, ErrPrerequisites
+	}
+
+	C.free(unsafe.Pointer(buf))
+	C.free(unsafe.Pointer(cs))
+	return true, nil
+}

vendor/src/github.com/containers/storage/drivers/driver_unsupported.go

@@ -0,0 +1,15 @@
+// +build !linux,!windows,!freebsd,!solaris
+
+package graphdriver
+
+var (
+	// Slice of drivers that should be used in an order
+	priority = []string{
+		"unsupported",
+	}
+)
+
+// GetFSMagic returns the filesystem id given the path.
+func GetFSMagic(rootpath string) (FsMagic, error) {
+	return FsMagicUnsupported, nil
+}

vendor/src/github.com/containers/storage/drivers/driver_windows.go

@@ -0,0 +1,14 @@
+package graphdriver
+
+var (
+	// Slice of drivers that should be used in order
+	priority = []string{
+		"windowsfilter",
+	}
+)
+
+// GetFSMagic returns the filesystem id given the path.
+func GetFSMagic(rootpath string) (FsMagic, error) {
+	// Note it is OK to return FsMagicUnsupported on Windows.
+	return FsMagicUnsupported, nil
+}

vendor/src/github.com/containers/storage/drivers/fsdiff.go

@@ -0,0 +1,157 @@
+package graphdriver
+
+import (
+	"time"
+
+	"github.com/Sirupsen/logrus"
+
+	"github.com/containers/storage/pkg/archive"
+	"github.com/containers/storage/pkg/chrootarchive"
+	"github.com/containers/storage/pkg/idtools"
+	"github.com/containers/storage/pkg/ioutils"
+)
+
+var (
+	// ApplyUncompressedLayer defines the unpack method used by the graph
+	// driver.
+	ApplyUncompressedLayer = chrootarchive.ApplyUncompressedLayer
+)
+
+// NaiveDiffDriver takes a ProtoDriver and adds the
+// capability of the Diffing methods which it may or may not
+// support on its own. See the comment on the exported
+// NewNaiveDiffDriver function below.
+// Notably, the AUFS driver doesn't need to be wrapped like this.
+type NaiveDiffDriver struct {
+	ProtoDriver
+	uidMaps []idtools.IDMap
+	gidMaps []idtools.IDMap
+}
+
+// NewNaiveDiffDriver returns a fully functional driver that wraps the
+// given ProtoDriver and adds the capability of the following methods which
+// it may or may not support on its own:
+//     Diff(id, parent string) (archive.Archive, error)
+//     Changes(id, parent string) ([]archive.Change, error)
+//     ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error)
+//     DiffSize(id, parent string) (size int64, err error)
+func NewNaiveDiffDriver(driver ProtoDriver, uidMaps, gidMaps []idtools.IDMap) Driver {
+	gdw := &NaiveDiffDriver{
+		ProtoDriver: driver,
+		uidMaps:     uidMaps,
+		gidMaps:     gidMaps,
+	}
+	return gdw
+}
+
+// Diff produces an archive of the changes between the specified
+// layer and its parent layer which may be "".
+func (gdw *NaiveDiffDriver) Diff(id, parent string) (arch archive.Archive, err error) {
+	layerFs, err := gdw.Get(id, "")
+	if err != nil {
+		return nil, err
+	}
+
+	defer func() {
+		if err != nil {
+			gdw.Put(id)
+		}
+	}()
+
+	if parent == "" {
+		archive, err := archive.Tar(layerFs, archive.Uncompressed)
+		if err != nil {
+			return nil, err
+		}
+		return ioutils.NewReadCloserWrapper(archive, func() error {
+			err := archive.Close()
+			gdw.Put(id)
+			return err
+		}), nil
+	}
+
+	parentFs, err := gdw.Get(parent, "")
+	if err != nil {
+		return nil, err
+	}
+	defer gdw.Put(parent)
+
+	changes, err := archive.ChangesDirs(layerFs, parentFs)
+	if err != nil {
+		return nil, err
+	}
+
+	archive, err := archive.ExportChanges(layerFs, changes, gdw.uidMaps, gdw.gidMaps)
+	if err != nil {
+		return nil, err
+	}
+
+	return ioutils.NewReadCloserWrapper(archive, func() error {
+		err := archive.Close()
+		gdw.Put(id)
+		return err
+	}), nil
+}
+
+// Changes produces a list of changes between the specified layer
+// and its parent layer. If parent is "", then all changes will be ADD changes.
+func (gdw *NaiveDiffDriver) Changes(id, parent string) ([]archive.Change, error) {
+	layerFs, err := gdw.Get(id, "")
+	if err != nil {
+		return nil, err
+	}
+	defer gdw.Put(id)
+
+	parentFs := ""
+
+	if parent != "" {
+		parentFs, err = gdw.Get(parent, "")
+		if err != nil {
+			return nil, err
+		}
+		defer gdw.Put(parent)
+	}
+
+	return archive.ChangesDirs(layerFs, parentFs)
+}
+
+// ApplyDiff extracts the changeset from the given diff into the
+// layer with the specified id and parent, returning the size of the
+// new layer in bytes.
+func (gdw *NaiveDiffDriver) ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error) {
+	// Mount the root filesystem so we can apply the diff/layer.
+	layerFs, err := gdw.Get(id, "")
+	if err != nil {
+		return
+	}
+	defer gdw.Put(id)
+
+	options := &archive.TarOptions{UIDMaps: gdw.uidMaps,
+		GIDMaps: gdw.gidMaps}
+	start := time.Now().UTC()
+	logrus.Debug("Start untar layer")
+	if size, err = ApplyUncompressedLayer(layerFs, diff, options); err != nil {
+		return
+	}
+	logrus.Debugf("Untar time: %vs", time.Now().UTC().Sub(start).Seconds())
+
+	return
+}
+
+// DiffSize calculates the changes between the specified layer
+// and its parent and returns the size in bytes of the changes
+// relative to its base filesystem directory.
+func (gdw *NaiveDiffDriver) DiffSize(id, parent string) (size int64, err error) {
+	changes, err := gdw.Changes(id, parent)
+	if err != nil {
+		return
+	}
+
+	layerFs, err := gdw.Get(id, "")
+	if err != nil {
+		return
+	}
+	defer gdw.Put(id)
+
+	return archive.ChangesSize(layerFs, changes), nil
+}

vendor/src/github.com/containers/storage/drivers/overlay/copy.go

@@ -0,0 +1,169 @@
+// +build linux
+
+package overlay
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"syscall"
+	"time"
+
+	"github.com/containers/storage/pkg/pools"
+	"github.com/containers/storage/pkg/system"
+)
+
+type copyFlags int
+
+const (
+	copyHardlink copyFlags = 1 << iota
+)
+
+func copyRegular(srcPath, dstPath string, mode os.FileMode) error {
+	srcFile, err := os.Open(srcPath)
+	if err != nil {
+		return err
+	}
+	defer srcFile.Close()
+
+	dstFile, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE, mode)
+	if err != nil {
+		return err
+	}
+	defer dstFile.Close()
+
+	_, err = pools.Copy(dstFile, srcFile)
+
+	return err
+}
+
+func copyXattr(srcPath, dstPath, attr string) error {
+	data, err := system.Lgetxattr(srcPath, attr)
+	if err != nil {
+		return err
+	}
+	if data != nil {
+		if err := system.Lsetxattr(dstPath, attr, data, 0); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func copyDir(srcDir, dstDir string, flags copyFlags) error {
+	err := filepath.Walk(srcDir, func(srcPath string, f os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		// Rebase path
+		relPath, err := filepath.Rel(srcDir, srcPath)
+		if err != nil {
+			return err
+		}
+
+		dstPath := filepath.Join(dstDir, relPath)
+		if err != nil {
+			return err
+		}
+
+		stat, ok := f.Sys().(*syscall.Stat_t)
+		if !ok {
+			return fmt.Errorf("Unable to get raw syscall.Stat_t data for %s", srcPath)
+		}
+
+		isHardlink := false
+
+		switch f.Mode() & os.ModeType {
+		case 0: // Regular file
+			if flags&copyHardlink != 0 {
+				isHardlink = true
+				if err := os.Link(srcPath, dstPath); err != nil {
+					return err
+				}
+			} else {
+				if err := copyRegular(srcPath, dstPath, f.Mode()); err != nil {
+					return err
+				}
+			}
+
+		case os.ModeDir:
+			if err := os.Mkdir(dstPath, f.Mode()); err != nil && !os.IsExist(err) {
+				return err
+			}
+
+		case os.ModeSymlink:
+			link, err := os.Readlink(srcPath)
+			if err != nil {
+				return err
+			}
+
+			if err := os.Symlink(link, dstPath); err != nil {
+				return err
+			}
+
+		case os.ModeNamedPipe:
+			fallthrough
+		case os.ModeSocket:
+			if err := syscall.Mkfifo(dstPath, stat.Mode); err != nil {
+				return err
+			}
+
+		case os.ModeDevice:
+			if err := syscall.Mknod(dstPath, stat.Mode, int(stat.Rdev)); err != nil {
+				return err
+			}
+
+		default:
+			return fmt.Errorf("Unknown file type for %s\n", srcPath)
+		}
+
+		// Everything below is copying metadata from src to dst. All this metadata
+		// already shares an inode for hardlinks.
+		if isHardlink {
+			return nil
+		}
+
+		if err := os.Lchown(dstPath, int(stat.Uid), int(stat.Gid)); err != nil {
+			return err
+		}
+
+		if err := copyXattr(srcPath, dstPath, "security.capability"); err != nil {
+			return err
+		}
+
+		// We need to copy this attribute if it appears in an overlay upper layer, as
+		// this function is used to copy those. It is set by overlay if a directory
+		// is removed and then re-created and should not inherit anything from the
+		// same dir in the lower dir.
+		if err := copyXattr(srcPath, dstPath, "trusted.overlay.opaque"); err != nil {
+			return err
+		}
+
+		isSymlink := f.Mode()&os.ModeSymlink != 0
+
+		// There is no LChmod, so ignore mode for symlink. Also, this
+		// must happen after chown, as that can modify the file mode
+		if !isSymlink {
+			if err := os.Chmod(dstPath, f.Mode()); err != nil {
+				return err
+			}
+		}
+
+		// system.Chtimes doesn't support a NOFOLLOW flag atm
+		if !isSymlink {
+			aTime := time.Unix(int64(stat.Atim.Sec), int64(stat.Atim.Nsec))
+			mTime := time.Unix(int64(stat.Mtim.Sec), int64(stat.Mtim.Nsec))
+			if err := system.Chtimes(dstPath, aTime, mTime); err != nil {
+				return err
+			}
+		} else {
+			ts := []syscall.Timespec{stat.Atim, stat.Mtim}
+			if err := system.LUtimesNano(dstPath, ts); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+	return err
+}

vendor/src/github.com/containers/storage/drivers/overlay/overlay.go

@@ -0,0 +1,450 @@
+// +build linux
+
+package overlay
+
+import (
+	"bufio"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+
+	"github.com/containers/storage/drivers"
+	"github.com/containers/storage/pkg/archive"
+	"github.com/containers/storage/pkg/idtools"
+
+	"github.com/containers/storage/pkg/mount"
+	"github.com/opencontainers/runc/libcontainer/label"
+)
+
+// This is a small wrapper over the NaiveDiffWriter that lets us have a custom
+// implementation of ApplyDiff()
+
+var (
+	// ErrApplyDiffFallback is returned to indicate that a normal ApplyDiff is applied as a fallback from Naive diff writer.
+	ErrApplyDiffFallback = fmt.Errorf("Fall back to normal ApplyDiff")
+	backingFs            = "<unknown>"
+)
+
+// ApplyDiffProtoDriver wraps the ProtoDriver by extending the interface with ApplyDiff method.
+type ApplyDiffProtoDriver interface {
+	graphdriver.ProtoDriver
+	// ApplyDiff writes the diff to the archive for the given id and parent id.
+	// It returns the size in bytes written if successful, an error ErrApplyDiffFallback is returned otherwise.
+	ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error)
+}
+
+type naiveDiffDriverWithApply struct {
+	graphdriver.Driver
+	applyDiff ApplyDiffProtoDriver
+}
+
+// NaiveDiffDriverWithApply returns a NaiveDiff driver with custom ApplyDiff.
+func NaiveDiffDriverWithApply(driver ApplyDiffProtoDriver, uidMaps, gidMaps []idtools.IDMap) graphdriver.Driver {
+	return &naiveDiffDriverWithApply{
+		Driver:    graphdriver.NewNaiveDiffDriver(driver, uidMaps, gidMaps),
+		applyDiff: driver,
+	}
+}
+
+// ApplyDiff creates a diff layer with either the NaiveDiffDriver or with a fallback.
+func (d *naiveDiffDriverWithApply) ApplyDiff(id, parent string, diff archive.Reader) (int64, error) {
+	b, err := d.applyDiff.ApplyDiff(id, parent, diff)
+	if err == ErrApplyDiffFallback {
+		return d.Driver.ApplyDiff(id, parent, diff)
+	}
+	return b, err
+}
+
+// This backend uses the overlay union filesystem for containers
+// plus hard link file sharing for images.
+
+// Each container/image can have a "root" subdirectory which is a plain
+// filesystem hierarchy, or they can use overlay.
+
+// If they use overlay there is a "upper" directory and a "lower-id"
+// file, as well as "merged" and "work" directories. The "upper"
+// directory has the upper layer of the overlay, and "lower-id" contains
+// the id of the parent whose "root" directory shall be used as the lower
+// layer in the overlay. The overlay itself is mounted in the "merged"
+// directory, and the "work" dir is needed for overlay to work.
+
+// When an overlay layer is created there are two cases, either the
+// parent has a "root" dir, then we start out with an empty "upper"
+// directory overlaid on the parents root. This is typically the
+// case with the init layer of a container which is based on an image.
+// If there is no "root" in the parent, we inherit the lower-id from
+// the parent and start by making a copy in the parent's "upper" dir.
+// This is typically the case for a container layer which copies
+// its parent -init upper layer.
+
+// Additionally we also have a custom implementation of ApplyLayer
+// which makes a recursive copy of the parent "root" layer using
+// hardlinks to share file data, and then applies the layer on top
+// of that. This means all child images share file (but not directory)
+// data with the parent.
+
+// Driver contains information about the home directory and the list of active mounts that are created using this driver.
+type Driver struct {
+	home    string
+	uidMaps []idtools.IDMap
+	gidMaps []idtools.IDMap
+	ctr     *graphdriver.RefCounter
+}
+
+func init() {
+	graphdriver.Register("overlay", Init)
+}
+
+// Init returns the NaiveDiffDriver, a native diff driver for overlay filesystem.
+// If overlay filesystem is not supported on the host, graphdriver.ErrNotSupported is returned as error.
+// If an overlay filesystem is not supported over an existing filesystem then error graphdriver.ErrIncompatibleFS is returned.
+func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
+
+	if err := supportsOverlay(); err != nil {
+		return nil, graphdriver.ErrNotSupported
+	}
+
+	fsMagic, err := graphdriver.GetFSMagic(home)
+	if err != nil {
+		return nil, err
+	}
+	if fsName, ok := graphdriver.FsNames[fsMagic]; ok {
+		backingFs = fsName
+	}
+
+	switch fsMagic {
+	case graphdriver.FsMagicAufs, graphdriver.FsMagicBtrfs, graphdriver.FsMagicOverlay, graphdriver.FsMagicZfs, graphdriver.FsMagicEcryptfs:
+		logrus.Errorf("'overlay' is not supported over %s", backingFs)
+		return nil, graphdriver.ErrIncompatibleFS
+	}
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
+	if err != nil {
+		return nil, err
+	}
+	// Create the driver home dir
+	if err := idtools.MkdirAllAs(home, 0700, rootUID, rootGID); err != nil && !os.IsExist(err) {
+		return nil, err
+	}
+
+	if err := mount.MakePrivate(home); err != nil {
+		return nil, err
+	}
+
+	d := &Driver{
+		home:    home,
+		uidMaps: uidMaps,
+		gidMaps: gidMaps,
+		ctr:     graphdriver.NewRefCounter(graphdriver.NewFsChecker(graphdriver.FsMagicOverlay)),
+	}
+
+	return NaiveDiffDriverWithApply(d, uidMaps, gidMaps), nil
+}
+
+func supportsOverlay() error {
+	// We can try to modprobe overlay first before looking at
+	// proc/filesystems for when overlay is supported
+	exec.Command("modprobe", "overlay").Run()
+
+	f, err := os.Open("/proc/filesystems")
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	s := bufio.NewScanner(f)
+	for s.Scan() {
+		if s.Text() == "nodev\toverlay" {
+			return nil
+		}
+	}
+	logrus.Error("'overlay' not found as a supported filesystem on this host. Please ensure kernel is new enough and has overlay support loaded.")
+	return graphdriver.ErrNotSupported
+}
+
+func (d *Driver) String() string {
+	return "overlay"
+}
+
+// Status returns current driver information in a two dimensional string array.
+// Output contains "Backing Filesystem" used in this implementation.
+func (d *Driver) Status() [][2]string {
+	return [][2]string{
+		{"Backing Filesystem", backingFs},
+	}
+}
+
+// GetMetadata returns meta data about the overlay driver such as root, LowerDir, UpperDir, WorkDir and MergeDir used to store data.
+func (d *Driver) GetMetadata(id string) (map[string]string, error) {
+	dir := d.dir(id)
+	if _, err := os.Stat(dir); err != nil {
+		return nil, err
+	}
+
+	metadata := make(map[string]string)
+
+	// If id has a root, it is an image
+	rootDir := path.Join(dir, "root")
+	if _, err := os.Stat(rootDir); err == nil {
+		metadata["RootDir"] = rootDir
+		return metadata, nil
+	}
+
+	lowerID, err := ioutil.ReadFile(path.Join(dir, "lower-id"))
+	if err != nil {
+		return nil, err
+	}
+
+	metadata["LowerDir"] = path.Join(d.dir(string(lowerID)), "root")
+	metadata["UpperDir"] = path.Join(dir, "upper")
+	metadata["WorkDir"] = path.Join(dir, "work")
+	metadata["MergedDir"] = path.Join(dir, "merged")
+
+	return metadata, nil
+}
+
+// Cleanup any state created by overlay which should be cleaned when daemon
+// is being shutdown. For now, we just have to unmount the bind mounted
+// we had created.
+func (d *Driver) Cleanup() error {
+	return mount.Unmount(d.home)
+}
+
+// CreateReadWrite creates a layer that is writable for use as a container
+// file system.
+func (d *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	return d.Create(id, parent, mountLabel, storageOpt)
+}
+
+// Create is used to create the upper, lower, and merge directories required for overlay fs for a given id.
+// The parent filesystem is used to configure these directories for the overlay.
+func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]string) (retErr error) {
+
+	if len(storageOpt) != 0 {
+		return fmt.Errorf("--storage-opt is not supported for overlay")
+	}
+
+	dir := d.dir(id)
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		return err
+	}
+	if err := idtools.MkdirAllAs(path.Dir(dir), 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+	if err := idtools.MkdirAs(dir, 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+
+	defer func() {
+		// Clean up on failure
+		if retErr != nil {
+			os.RemoveAll(dir)
+		}
+	}()
+
+	// Toplevel images are just a "root" dir
+	if parent == "" {
+		if err := idtools.MkdirAs(path.Join(dir, "root"), 0755, rootUID, rootGID); err != nil {
+			return err
+		}
+		return nil
+	}
+
+	parentDir := d.dir(parent)
+
+	// Ensure parent exists
+	if _, err := os.Lstat(parentDir); err != nil {
+		return err
+	}
+
+	// If parent has a root, just do an overlay to it
+	parentRoot := path.Join(parentDir, "root")
+
+	if s, err := os.Lstat(parentRoot); err == nil {
+		if err := idtools.MkdirAs(path.Join(dir, "upper"), s.Mode(), rootUID, rootGID); err != nil {
+			return err
+		}
+		if err := idtools.MkdirAs(path.Join(dir, "work"), 0700, rootUID, rootGID); err != nil {
+			return err
+		}
+		if err := idtools.MkdirAs(path.Join(dir, "merged"), 0700, rootUID, rootGID); err != nil {
+			return err
+		}
+		if err := ioutil.WriteFile(path.Join(dir, "lower-id"), []byte(parent), 0666); err != nil {
+			return err
+		}
+		return nil
+	}
+
+	// Otherwise, copy the upper and the lower-id from the parent
+
+	lowerID, err := ioutil.ReadFile(path.Join(parentDir, "lower-id"))
+	if err != nil {
+		return err
+	}
+
+	if err := ioutil.WriteFile(path.Join(dir, "lower-id"), lowerID, 0666); err != nil {
+		return err
+	}
+
+	parentUpperDir := path.Join(parentDir, "upper")
+	s, err := os.Lstat(parentUpperDir)
+	if err != nil {
+		return err
+	}
+
+	upperDir := path.Join(dir, "upper")
+	if err := idtools.MkdirAs(upperDir, s.Mode(), rootUID, rootGID); err != nil {
+		return err
+	}
+	if err := idtools.MkdirAs(path.Join(dir, "work"), 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+	if err := idtools.MkdirAs(path.Join(dir, "merged"), 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+
+	return copyDir(parentUpperDir, upperDir, 0)
+}
+
+func (d *Driver) dir(id string) string {
+	return path.Join(d.home, id)
+}
+
+// Remove cleans the directories that are created for this id.
+func (d *Driver) Remove(id string) error {
+	if err := os.RemoveAll(d.dir(id)); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	return nil
+}
+
+// Get creates and mounts the required file system for the given id and returns the mount path.
+func (d *Driver) Get(id string, mountLabel string) (s string, err error) {
+	dir := d.dir(id)
+	if _, err := os.Stat(dir); err != nil {
+		return "", err
+	}
+	// If id has a root, just return it
+	rootDir := path.Join(dir, "root")
+	if _, err := os.Stat(rootDir); err == nil {
+		return rootDir, nil
+	}
+	mergedDir := path.Join(dir, "merged")
+	if count := d.ctr.Increment(mergedDir); count > 1 {
+		return mergedDir, nil
+	}
+	defer func() {
+		if err != nil {
+			if c := d.ctr.Decrement(mergedDir); c <= 0 {
+				syscall.Unmount(mergedDir, 0)
+			}
+		}
+	}()
+	lowerID, err := ioutil.ReadFile(path.Join(dir, "lower-id"))
+	if err != nil {
+		return "", err
+	}
+	var (
+		lowerDir = path.Join(d.dir(string(lowerID)), "root")
+		upperDir = path.Join(dir, "upper")
+		workDir  = path.Join(dir, "work")
+		opts     = fmt.Sprintf("lowerdir=%s,upperdir=%s,workdir=%s", lowerDir, upperDir, workDir)
+	)
+	if err := syscall.Mount("overlay", mergedDir, "overlay", 0, label.FormatMountLabel(opts, mountLabel)); err != nil {
+		return "", fmt.Errorf("error creating overlay mount to %s: %v", mergedDir, err)
+	}
+	// chown "workdir/work" to the remapped root UID/GID. Overlay fs inside a
+	// user namespace requires this to move a directory from lower to upper.
+	rootUID, rootGID, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		return "", err
+	}
+	if err := os.Chown(path.Join(workDir, "work"), rootUID, rootGID); err != nil {
+		return "", err
+	}
+	return mergedDir, nil
+}
+
+// Put unmounts the mount path created for the give id.
+func (d *Driver) Put(id string) error {
+	mountpoint := path.Join(d.dir(id), "merged")
+	if count := d.ctr.Decrement(mountpoint); count > 0 {
+		return nil
+	}
+	err := syscall.Unmount(mountpoint, 0)
+	if err != nil {
+		rootDir := path.Join(d.dir(id), "root")
+		if _, err := os.Stat(rootDir); err == nil {
+			// We weren't mounting a "merged" directory anyway
+			return nil
+		}
+		logrus.Debugf("Failed to unmount %s overlay: %v", id, err)
+	}
+	return err
+}
+
+// ApplyDiff applies the new layer on top of the root, if parent does not exist with will return an ErrApplyDiffFallback error.
+func (d *Driver) ApplyDiff(id string, parent string, diff archive.Reader) (size int64, err error) {
+	dir := d.dir(id)
+
+	if parent == "" {
+		return 0, ErrApplyDiffFallback
+	}
+
+	parentRootDir := path.Join(d.dir(parent), "root")
+	if _, err := os.Stat(parentRootDir); err != nil {
+		return 0, ErrApplyDiffFallback
+	}
+
+	// We now know there is a parent, and it has a "root" directory containing
+	// the full root filesystem. We can just hardlink it and apply the
+	// layer. This relies on two things:
+	// 1) ApplyDiff is only run once on a clean (no writes to upper layer) container
+	// 2) ApplyDiff doesn't do any in-place writes to files (would break hardlinks)
+	// These are all currently true and are not expected to break
+
+	tmpRootDir, err := ioutil.TempDir(dir, "tmproot")
+	if err != nil {
+		return 0, err
+	}
+	defer func() {
+		if err != nil {
+			os.RemoveAll(tmpRootDir)
+		} else {
+			os.RemoveAll(path.Join(dir, "upper"))
+			os.RemoveAll(path.Join(dir, "work"))
+			os.RemoveAll(path.Join(dir, "merged"))
+			os.RemoveAll(path.Join(dir, "lower-id"))
+		}
+	}()
+
+	if err = copyDir(parentRootDir, tmpRootDir, copyHardlink); err != nil {
+		return 0, err
+	}
+
+	options := &archive.TarOptions{UIDMaps: d.uidMaps, GIDMaps: d.gidMaps}
+	if size, err = graphdriver.ApplyUncompressedLayer(tmpRootDir, diff, options); err != nil {
+		return 0, err
+	}
+
+	rootDir := path.Join(dir, "root")
+	if err := os.Rename(tmpRootDir, rootDir); err != nil {
+		return 0, err
+	}
+
+	return
+}
+
+// Exists checks to see if the id is already mounted.
+func (d *Driver) Exists(id string) bool {
+	_, err := os.Stat(d.dir(id))
+	return err == nil
+}

vendor/src/github.com/containers/storage/drivers/overlay/overlay_unsupported.go

@@ -0,0 +1,3 @@
+// +build !linux
+
+package overlay

vendor/src/github.com/containers/storage/drivers/overlay2/mount.go

@@ -0,0 +1,88 @@
+// +build linux
+
+package overlay2
+
+import (
+	"bytes"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"os"
+	"runtime"
+	"syscall"
+
+	"github.com/containers/storage/pkg/reexec"
+)
+
+func init() {
+	reexec.Register("docker-mountfrom", mountFromMain)
+}
+
+func fatal(err error) {
+	fmt.Fprint(os.Stderr, err)
+	os.Exit(1)
+}
+
+type mountOptions struct {
+	Device string
+	Target string
+	Type   string
+	Label  string
+	Flag   uint32
+}
+
+func mountFrom(dir, device, target, mType, label string) error {
+	options := &mountOptions{
+		Device: device,
+		Target: target,
+		Type:   mType,
+		Flag:   0,
+		Label:  label,
+	}
+
+	cmd := reexec.Command("docker-mountfrom", dir)
+	w, err := cmd.StdinPipe()
+	if err != nil {
+		return fmt.Errorf("mountfrom error on pipe creation: %v", err)
+	}
+
+	output := bytes.NewBuffer(nil)
+	cmd.Stdout = output
+	cmd.Stderr = output
+
+	if err := cmd.Start(); err != nil {
+		return fmt.Errorf("mountfrom error on re-exec cmd: %v", err)
+	}
+	//write the options to the pipe for the untar exec to read
+	if err := json.NewEncoder(w).Encode(options); err != nil {
+		return fmt.Errorf("mountfrom json encode to pipe failed: %v", err)
+	}
+	w.Close()
+
+	if err := cmd.Wait(); err != nil {
+		return fmt.Errorf("mountfrom re-exec error: %v: output: %s", err, output)
+	}
+	return nil
+}
+
+// mountfromMain is the entry-point for docker-mountfrom on re-exec.
+func mountFromMain() {
+	runtime.LockOSThread()
+	flag.Parse()
+
+	var options *mountOptions
+
+	if err := json.NewDecoder(os.Stdin).Decode(&options); err != nil {
+		fatal(err)
+	}
+
+	if err := os.Chdir(flag.Arg(0)); err != nil {
+		fatal(err)
+	}
+
+	if err := syscall.Mount(options.Device, options.Target, options.Type, uintptr(options.Flag), options.Label); err != nil {
+		fatal(err)
+	}
+
+	os.Exit(0)
+}

vendor/src/github.com/containers/storage/drivers/overlay2/overlay.go

@@ -0,0 +1,514 @@
+// +build linux
+
+package overlay2
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+
+	"github.com/containers/storage/drivers"
+	"github.com/containers/storage/pkg/archive"
+	"github.com/containers/storage/pkg/chrootarchive"
+	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/idtools"
+	"github.com/containers/storage/pkg/mount"
+	"github.com/containers/storage/pkg/parsers"
+	"github.com/containers/storage/pkg/parsers/kernel"
+
+	"github.com/opencontainers/runc/libcontainer/label"
+)
+
+var (
+	// untar defines the untar method
+	untar = chrootarchive.UntarUncompressed
+)
+
+// This backend uses the overlay union filesystem for containers
+// with diff directories for each layer.
+
+// This version of the overlay driver requires at least kernel
+// 4.0.0 in order to support mounting multiple diff directories.
+
+// Each container/image has at least a "diff" directory and "link" file.
+// If there is also a "lower" file when there are diff layers
+// below  as well as "merged" and "work" directories. The "diff" directory
+// has the upper layer of the overlay and is used to capture any
+// changes to the layer. The "lower" file contains all the lower layer
+// mounts separated by ":" and ordered from uppermost to lowermost
+// layers. The overlay itself is mounted in the "merged" directory,
+// and the "work" dir is needed for overlay to work.
+
+// The "link" file for each layer contains a unique string for the layer.
+// Under the "l" directory at the root there will be a symbolic link
+// with that unique string pointing the "diff" directory for the layer.
+// The symbolic links are used to reference lower layers in the "lower"
+// file and on mount. The links are used to shorten the total length
+// of a layer reference without requiring changes to the layer identifier
+// or root directory. Mounts are always done relative to root and
+// referencing the symbolic links in order to ensure the number of
+// lower directories can fit in a single page for making the mount
+// syscall. A hard upper limit of 128 lower layers is enforced to ensure
+// that mounts do not fail due to length.
+
+const (
+	driverName = "overlay2"
+	linkDir    = "l"
+	lowerFile  = "lower"
+	maxDepth   = 128
+
+	// idLength represents the number of random characters
+	// which can be used to create the unique link identifer
+	// for every layer. If this value is too long then the
+	// page size limit for the mount command may be exceeded.
+	// The idLength should be selected such that following equation
+	// is true (512 is a buffer for label metadata).
+	// ((idLength + len(linkDir) + 1) * maxDepth) <= (pageSize - 512)
+	idLength = 26
+)
+
+// Driver contains information about the home directory and the list of active mounts that are created using this driver.
+type Driver struct {
+	home    string
+	uidMaps []idtools.IDMap
+	gidMaps []idtools.IDMap
+	ctr     *graphdriver.RefCounter
+}
+
+var backingFs = "<unknown>"
+
+func init() {
+	graphdriver.Register(driverName, Init)
+}
+
+// Init returns the a native diff driver for overlay filesystem.
+// If overlay filesystem is not supported on the host, graphdriver.ErrNotSupported is returned as error.
+// If a overlay filesystem is not supported over a existing filesystem then error graphdriver.ErrIncompatibleFS is returned.
+func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
+	opts, err := parseOptions(options)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := supportsOverlay(); err != nil {
+		return nil, graphdriver.ErrNotSupported
+	}
+
+	// require kernel 4.0.0 to ensure multiple lower dirs are supported
+	v, err := kernel.GetKernelVersion()
+	if err != nil {
+		return nil, err
+	}
+	if kernel.CompareKernelVersion(*v, kernel.VersionInfo{Kernel: 4, Major: 0, Minor: 0}) < 0 {
+		if !opts.overrideKernelCheck {
+			return nil, graphdriver.ErrNotSupported
+		}
+		logrus.Warnf("Using pre-4.0.0 kernel for overlay2, mount failures may require kernel update")
+	}
+
+	fsMagic, err := graphdriver.GetFSMagic(home)
+	if err != nil {
+		return nil, err
+	}
+	if fsName, ok := graphdriver.FsNames[fsMagic]; ok {
+		backingFs = fsName
+	}
+
+	// check if they are running over btrfs, aufs, zfs, overlay, or ecryptfs
+	switch fsMagic {
+	case graphdriver.FsMagicBtrfs, graphdriver.FsMagicAufs, graphdriver.FsMagicZfs, graphdriver.FsMagicOverlay, graphdriver.FsMagicEcryptfs:
+		logrus.Errorf("'overlay2' is not supported over %s", backingFs)
+		return nil, graphdriver.ErrIncompatibleFS
+	}
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
+	if err != nil {
+		return nil, err
+	}
+	// Create the driver home dir
+	if err := idtools.MkdirAllAs(path.Join(home, linkDir), 0700, rootUID, rootGID); err != nil && !os.IsExist(err) {
+		return nil, err
+	}
+
+	if err := mount.MakePrivate(home); err != nil {
+		return nil, err
+	}
+
+	d := &Driver{
+		home:    home,
+		uidMaps: uidMaps,
+		gidMaps: gidMaps,
+		ctr:     graphdriver.NewRefCounter(graphdriver.NewFsChecker(graphdriver.FsMagicOverlay)),
+	}
+
+	return d, nil
+}
+
+type overlayOptions struct {
+	overrideKernelCheck bool
+}
+
+func parseOptions(options []string) (*overlayOptions, error) {
+	o := &overlayOptions{}
+	for _, option := range options {
+		key, val, err := parsers.ParseKeyValueOpt(option)
+		if err != nil {
+			return nil, err
+		}
+		key = strings.ToLower(key)
+		switch key {
+		case "overlay2.override_kernel_check":
+			o.overrideKernelCheck, err = strconv.ParseBool(val)
+			if err != nil {
+				return nil, err
+			}
+		default:
+			return nil, fmt.Errorf("overlay2: Unknown option %s\n", key)
+		}
+	}
+	return o, nil
+}
+
+func supportsOverlay() error {
+	// We can try to modprobe overlay first before looking at
+	// proc/filesystems for when overlay is supported
+	exec.Command("modprobe", "overlay").Run()
+
+	f, err := os.Open("/proc/filesystems")
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	s := bufio.NewScanner(f)
+	for s.Scan() {
+		if s.Text() == "nodev\toverlay" {
+			return nil
+		}
+	}
+	logrus.Error("'overlay' not found as a supported filesystem on this host. Please ensure kernel is new enough and has overlay support loaded.")
+	return graphdriver.ErrNotSupported
+}
+
+func (d *Driver) String() string {
+	return driverName
+}
+
+// Status returns current driver information in a two dimensional string array.
+// Output contains "Backing Filesystem" used in this implementation.
+func (d *Driver) Status() [][2]string {
+	return [][2]string{
+		{"Backing Filesystem", backingFs},
+	}
+}
+
+// GetMetadata returns meta data about the overlay driver such as
+// LowerDir, UpperDir, WorkDir and MergeDir used to store data.
+func (d *Driver) GetMetadata(id string) (map[string]string, error) {
+	dir := d.dir(id)
+	if _, err := os.Stat(dir); err != nil {
+		return nil, err
+	}
+
+	metadata := map[string]string{
+		"WorkDir":   path.Join(dir, "work"),
+		"MergedDir": path.Join(dir, "merged"),
+		"UpperDir":  path.Join(dir, "diff"),
+	}
+
+	lowerDirs, err := d.getLowerDirs(id)
+	if err != nil {
+		return nil, err
+	}
+	if len(lowerDirs) > 0 {
+		metadata["LowerDir"] = strings.Join(lowerDirs, ":")
+	}
+
+	return metadata, nil
+}
+
+// Cleanup any state created by overlay which should be cleaned when daemon
+// is being shutdown. For now, we just have to unmount the bind mounted
+// we had created.
+func (d *Driver) Cleanup() error {
+	return mount.Unmount(d.home)
+}
+
+// CreateReadWrite creates a layer that is writable for use as a container
+// file system.
+func (d *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	return d.Create(id, parent, mountLabel, storageOpt)
+}
+
+// Create is used to create the upper, lower, and merge directories required for overlay fs for a given id.
+// The parent filesystem is used to configure these directories for the overlay.
+func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]string) (retErr error) {
+
+	if len(storageOpt) != 0 {
+		return fmt.Errorf("--storage-opt is not supported for overlay")
+	}
+
+	dir := d.dir(id)
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		return err
+	}
+	if err := idtools.MkdirAllAs(path.Dir(dir), 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+	if err := idtools.MkdirAs(dir, 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+
+	defer func() {
+		// Clean up on failure
+		if retErr != nil {
+			os.RemoveAll(dir)
+		}
+	}()
+
+	if err := idtools.MkdirAs(path.Join(dir, "diff"), 0755, rootUID, rootGID); err != nil {
+		return err
+	}
+
+	lid := generateID(idLength)
+	if err := os.Symlink(path.Join("..", id, "diff"), path.Join(d.home, linkDir, lid)); err != nil {
+		return err
+	}
+
+	// Write link id to link file
+	if err := ioutil.WriteFile(path.Join(dir, "link"), []byte(lid), 0644); err != nil {
+		return err
+	}
+
+	// if no parent directory, done
+	if parent == "" {
+		return nil
+	}
+
+	if err := idtools.MkdirAs(path.Join(dir, "work"), 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+	if err := idtools.MkdirAs(path.Join(dir, "merged"), 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+
+	lower, err := d.getLower(parent)
+	if err != nil {
+		return err
+	}
+	if lower != "" {
+		if err := ioutil.WriteFile(path.Join(dir, lowerFile), []byte(lower), 0666); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (d *Driver) getLower(parent string) (string, error) {
+	parentDir := d.dir(parent)
+
+	// Ensure parent exists
+	if _, err := os.Lstat(parentDir); err != nil {
+		return "", err
+	}
+
+	// Read Parent link fileA
+	parentLink, err := ioutil.ReadFile(path.Join(parentDir, "link"))
+	if err != nil {
+		return "", err
+	}
+	lowers := []string{path.Join(linkDir, string(parentLink))}
+
+	parentLower, err := ioutil.ReadFile(path.Join(parentDir, lowerFile))
+	if err == nil {
+		parentLowers := strings.Split(string(parentLower), ":")
+		lowers = append(lowers, parentLowers...)
+	}
+	if len(lowers) > maxDepth {
+		return "", errors.New("max depth exceeded")
+	}
+	return strings.Join(lowers, ":"), nil
+}
+
+func (d *Driver) dir(id string) string {
+	return path.Join(d.home, id)
+}
+
+func (d *Driver) getLowerDirs(id string) ([]string, error) {
+	var lowersArray []string
+	lowers, err := ioutil.ReadFile(path.Join(d.dir(id), lowerFile))
+	if err == nil {
+		for _, s := range strings.Split(string(lowers), ":") {
+			lp, err := os.Readlink(path.Join(d.home, s))
+			if err != nil {
+				return nil, err
+			}
+			lowersArray = append(lowersArray, path.Clean(path.Join(d.home, "link", lp)))
+		}
+	} else if !os.IsNotExist(err) {
+		return nil, err
+	}
+	return lowersArray, nil
+}
+
+// Remove cleans the directories that are created for this id.
+func (d *Driver) Remove(id string) error {
+	dir := d.dir(id)
+	lid, err := ioutil.ReadFile(path.Join(dir, "link"))
+	if err == nil {
+		if err := os.RemoveAll(path.Join(d.home, linkDir, string(lid))); err != nil {
+			logrus.Debugf("Failed to remove link: %v", err)
+		}
+	}
+
+	if err := os.RemoveAll(dir); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	return nil
+}
+
+// Get creates and mounts the required file system for the given id and returns the mount path.
+func (d *Driver) Get(id string, mountLabel string) (s string, err error) {
+	dir := d.dir(id)
+	if _, err := os.Stat(dir); err != nil {
+		return "", err
+	}
+
+	diffDir := path.Join(dir, "diff")
+	lowers, err := ioutil.ReadFile(path.Join(dir, lowerFile))
+	if err != nil {
+		// If no lower, just return diff directory
+		if os.IsNotExist(err) {
+			return diffDir, nil
+		}
+		return "", err
+	}
+
+	mergedDir := path.Join(dir, "merged")
+	if count := d.ctr.Increment(mergedDir); count > 1 {
+		return mergedDir, nil
+	}
+	defer func() {
+		if err != nil {
+			if c := d.ctr.Decrement(mergedDir); c <= 0 {
+				syscall.Unmount(mergedDir, 0)
+			}
+		}
+	}()
+
+	workDir := path.Join(dir, "work")
+	opts := fmt.Sprintf("lowerdir=%s,upperdir=%s,workdir=%s", string(lowers), path.Join(id, "diff"), path.Join(id, "work"))
+	mountLabel = label.FormatMountLabel(opts, mountLabel)
+	if len(mountLabel) > syscall.Getpagesize() {
+		return "", fmt.Errorf("cannot mount layer, mount label too large %d", len(mountLabel))
+	}
+
+	if err := mountFrom(d.home, "overlay", path.Join(id, "merged"), "overlay", mountLabel); err != nil {
+		return "", fmt.Errorf("error creating overlay mount to %s: %v", mergedDir, err)
+	}
+
+	// chown "workdir/work" to the remapped root UID/GID. Overlay fs inside a
+	// user namespace requires this to move a directory from lower to upper.
+	rootUID, rootGID, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		return "", err
+	}
+
+	if err := os.Chown(path.Join(workDir, "work"), rootUID, rootGID); err != nil {
+		return "", err
+	}
+
+	return mergedDir, nil
+}
+
+// Put unmounts the mount path created for the give id.
+func (d *Driver) Put(id string) error {
+	mountpoint := path.Join(d.dir(id), "merged")
+	if count := d.ctr.Decrement(mountpoint); count > 0 {
+		return nil
+	}
+	err := syscall.Unmount(mountpoint, 0)
+	if err != nil {
+		if _, err := ioutil.ReadFile(path.Join(d.dir(id), lowerFile)); err != nil {
+			// We didn't have a "lower" directory, so we weren't mounting a "merged" directory anyway
+			return nil
+		}
+		logrus.Debugf("Failed to unmount %s overlay: %v", id, err)
+	}
+	return err
+}
+
+// Exists checks to see if the id is already mounted.
+func (d *Driver) Exists(id string) bool {
+	_, err := os.Stat(d.dir(id))
+	return err == nil
+}
+
+// ApplyDiff applies the new layer into a root
+func (d *Driver) ApplyDiff(id string, parent string, diff archive.Reader) (size int64, err error) {
+	applyDir := d.getDiffPath(id)
+
+	logrus.Debugf("Applying tar in %s", applyDir)
+	// Overlay doesn't need the parent id to apply the diff
+	if err := untar(diff, applyDir, &archive.TarOptions{
+		UIDMaps:        d.uidMaps,
+		GIDMaps:        d.gidMaps,
+		WhiteoutFormat: archive.OverlayWhiteoutFormat,
+	}); err != nil {
+		return 0, err
+	}
+
+	return d.DiffSize(id, parent)
+}
+
+func (d *Driver) getDiffPath(id string) string {
+	dir := d.dir(id)
+
+	return path.Join(dir, "diff")
+}
+
+// DiffSize calculates the changes between the specified id
+// and its parent and returns the size in bytes of the changes
+// relative to its base filesystem directory.
+func (d *Driver) DiffSize(id, parent string) (size int64, err error) {
+	return directory.Size(d.getDiffPath(id))
+}
+
+// Diff produces an archive of the changes between the specified
+// layer and its parent layer which may be "".
+func (d *Driver) Diff(id, parent string) (archive.Archive, error) {
+	diffPath := d.getDiffPath(id)
+	logrus.Debugf("Tar with options on %s", diffPath)
+	return archive.TarWithOptions(diffPath, &archive.TarOptions{
+		Compression:    archive.Uncompressed,
+		UIDMaps:        d.uidMaps,
+		GIDMaps:        d.gidMaps,
+		WhiteoutFormat: archive.OverlayWhiteoutFormat,
+	})
+}
+
+// Changes produces a list of changes between the specified layer
+// and its parent layer. If parent is "", then all changes will be ADD changes.
+func (d *Driver) Changes(id, parent string) ([]archive.Change, error) {
+	// Overlay doesn't have snapshots, so we need to get changes from all parent
+	// layers.
+	diffPath := d.getDiffPath(id)
+	layers, err := d.getLowerDirs(id)
+	if err != nil {
+		return nil, err
+	}
+
+	return archive.OverlayChanges(layers, diffPath)
+}

vendor/src/github.com/containers/storage/drivers/overlay2/overlay_unsupported.go

@@ -0,0 +1,3 @@
+// +build !linux
+
+package overlay2

vendor/src/github.com/containers/storage/drivers/overlay2/randomid.go

@@ -0,0 +1,80 @@
+// +build linux
+
+package overlay2
+
+import (
+	"crypto/rand"
+	"encoding/base32"
+	"fmt"
+	"io"
+	"os"
+	"syscall"
+	"time"
+
+	"github.com/Sirupsen/logrus"
+)
+
+// generateID creates a new random string identifier with the given length
+func generateID(l int) string {
+	const (
+		// ensures we backoff for less than 450ms total. Use the following to
+		// select new value, in units of 10ms:
+		// 	n*(n+1)/2 = d -> n^2 + n - 2d -> n = (sqrt(8d + 1) - 1)/2
+		maxretries = 9
+		backoff    = time.Millisecond * 10
+	)
+
+	var (
+		totalBackoff time.Duration
+		count        int
+		retries      int
+		size         = (l*5 + 7) / 8
+		u            = make([]byte, size)
+	)
+	// TODO: Include time component, counter component, random component
+
+	for {
+		// This should never block but the read may fail. Because of this,
+		// we just try to read the random number generator until we get
+		// something. This is a very rare condition but may happen.
+		b := time.Duration(retries) * backoff
+		time.Sleep(b)
+		totalBackoff += b
+
+		n, err := io.ReadFull(rand.Reader, u[count:])
+		if err != nil {
+			if retryOnError(err) && retries < maxretries {
+				count += n
+				retries++
+				logrus.Errorf("error generating version 4 uuid, retrying: %v", err)
+				continue
+			}
+
+			// Any other errors represent a system problem. What did someone
+			// do to /dev/urandom?
+			panic(fmt.Errorf("error reading random number generator, retried for %v: %v", totalBackoff.String(), err))
+		}
+
+		break
+	}
+
+	s := base32.StdEncoding.EncodeToString(u)
+
+	return s[:l]
+}
+
+// retryOnError tries to detect whether or not retrying would be fruitful.
+func retryOnError(err error) bool {
+	switch err := err.(type) {
+	case *os.PathError:
+		return retryOnError(err.Err) // unpack the target error
+	case syscall.Errno:
+		if err == syscall.EPERM {
+			// EPERM represents an entropy pool exhaustion, a condition under
+			// which we backoff and retry.
+			return true
+		}
+	}
+
+	return false
+}

vendor/src/github.com/containers/storage/drivers/plugin.go

@@ -0,0 +1,32 @@
+// +build experimental
+
+package graphdriver
+
+import (
+	"fmt"
+	"io"
+
+	"github.com/containers/storage/pkg/plugins"
+)
+
+type pluginClient interface {
+	// Call calls the specified method with the specified arguments for the plugin.
+	Call(string, interface{}, interface{}) error
+	// Stream calls the specified method with the specified arguments for the plugin and returns the response IO stream
+	Stream(string, interface{}) (io.ReadCloser, error)
+	// SendFile calls the specified method, and passes through the IO stream
+	SendFile(string, io.Reader, interface{}) error
+}
+
+func lookupPlugin(name, home string, opts []string) (Driver, error) {
+	pl, err := plugins.Get(name, "GraphDriver")
+	if err != nil {
+		return nil, fmt.Errorf("Error looking up graphdriver plugin %s: %v", name, err)
+	}
+	return newPluginDriver(name, home, opts, pl.Client())
+}
+
+func newPluginDriver(name, home string, opts []string, c pluginClient) (Driver, error) {
+	proxy := &graphDriverProxy{name, c}
+	return proxy, proxy.Init(home, opts)
+}

vendor/src/github.com/containers/storage/drivers/plugin_unsupported.go

@@ -0,0 +1,7 @@
+// +build !experimental
+
+package graphdriver
+
+func lookupPlugin(name, home string, opts []string) (Driver, error) {
+	return nil, ErrNotSupported
+}

vendor/src/github.com/containers/storage/drivers/proxy.go

@@ -0,0 +1,225 @@
+// +build experimental
+
+package graphdriver
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/containers/storage/pkg/archive"
+)
+
+type graphDriverProxy struct {
+	name   string
+	client pluginClient
+}
+
+type graphDriverRequest struct {
+	ID         string `json:",omitempty"`
+	Parent     string `json:",omitempty"`
+	MountLabel string `json:",omitempty"`
+}
+
+type graphDriverResponse struct {
+	Err      string            `json:",omitempty"`
+	Dir      string            `json:",omitempty"`
+	Exists   bool              `json:",omitempty"`
+	Status   [][2]string       `json:",omitempty"`
+	Changes  []archive.Change  `json:",omitempty"`
+	Size     int64             `json:",omitempty"`
+	Metadata map[string]string `json:",omitempty"`
+}
+
+type graphDriverInitRequest struct {
+	Home string
+	Opts []string
+}
+
+func (d *graphDriverProxy) Init(home string, opts []string) error {
+	args := &graphDriverInitRequest{
+		Home: home,
+		Opts: opts,
+	}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Init", args, &ret); err != nil {
+		return err
+	}
+	if ret.Err != "" {
+		return errors.New(ret.Err)
+	}
+	return nil
+}
+
+func (d *graphDriverProxy) String() string {
+	return d.name
+}
+
+func (d *graphDriverProxy) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	args := &graphDriverRequest{
+		ID:         id,
+		Parent:     parent,
+		MountLabel: mountLabel,
+	}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.CreateReadWrite", args, &ret); err != nil {
+		return err
+	}
+	if ret.Err != "" {
+		return errors.New(ret.Err)
+	}
+	return nil
+}
+
+func (d *graphDriverProxy) Create(id, parent, mountLabel string, storageOpt map[string]string) error {
+	args := &graphDriverRequest{
+		ID:         id,
+		Parent:     parent,
+		MountLabel: mountLabel,
+	}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Create", args, &ret); err != nil {
+		return err
+	}
+	if ret.Err != "" {
+		return errors.New(ret.Err)
+	}
+	return nil
+}
+
+func (d *graphDriverProxy) Remove(id string) error {
+	args := &graphDriverRequest{ID: id}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Remove", args, &ret); err != nil {
+		return err
+	}
+	if ret.Err != "" {
+		return errors.New(ret.Err)
+	}
+	return nil
+}
+
+func (d *graphDriverProxy) Get(id, mountLabel string) (string, error) {
+	args := &graphDriverRequest{
+		ID:         id,
+		MountLabel: mountLabel,
+	}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Get", args, &ret); err != nil {
+		return "", err
+	}
+	var err error
+	if ret.Err != "" {
+		err = errors.New(ret.Err)
+	}
+	return ret.Dir, err
+}
+
+func (d *graphDriverProxy) Put(id string) error {
+	args := &graphDriverRequest{ID: id}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Put", args, &ret); err != nil {
+		return err
+	}
+	if ret.Err != "" {
+		return errors.New(ret.Err)
+	}
+	return nil
+}
+
+func (d *graphDriverProxy) Exists(id string) bool {
+	args := &graphDriverRequest{ID: id}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Exists", args, &ret); err != nil {
+		return false
+	}
+	return ret.Exists
+}
+
+func (d *graphDriverProxy) Status() [][2]string {
+	args := &graphDriverRequest{}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Status", args, &ret); err != nil {
+		return nil
+	}
+	return ret.Status
+}
+
+func (d *graphDriverProxy) GetMetadata(id string) (map[string]string, error) {
+	args := &graphDriverRequest{
+		ID: id,
+	}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.GetMetadata", args, &ret); err != nil {
+		return nil, err
+	}
+	if ret.Err != "" {
+		return nil, errors.New(ret.Err)
+	}
+	return ret.Metadata, nil
+}
+
+func (d *graphDriverProxy) Cleanup() error {
+	args := &graphDriverRequest{}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Cleanup", args, &ret); err != nil {
+		return nil
+	}
+	if ret.Err != "" {
+		return errors.New(ret.Err)
+	}
+	return nil
+}
+
+func (d *graphDriverProxy) Diff(id, parent string) (archive.Archive, error) {
+	args := &graphDriverRequest{
+		ID:     id,
+		Parent: parent,
+	}
+	body, err := d.client.Stream("GraphDriver.Diff", args)
+	if err != nil {
+		return nil, err
+	}
+	return archive.Archive(body), nil
+}
+
+func (d *graphDriverProxy) Changes(id, parent string) ([]archive.Change, error) {
+	args := &graphDriverRequest{
+		ID:     id,
+		Parent: parent,
+	}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.Changes", args, &ret); err != nil {
+		return nil, err
+	}
+	if ret.Err != "" {
+		return nil, errors.New(ret.Err)
+	}
+
+	return ret.Changes, nil
+}
+
+func (d *graphDriverProxy) ApplyDiff(id, parent string, diff archive.Reader) (int64, error) {
+	var ret graphDriverResponse
+	if err := d.client.SendFile(fmt.Sprintf("GraphDriver.ApplyDiff?id=%s&parent=%s", id, parent), diff, &ret); err != nil {
+		return -1, err
+	}
+	if ret.Err != "" {
+		return -1, errors.New(ret.Err)
+	}
+	return ret.Size, nil
+}
+
+func (d *graphDriverProxy) DiffSize(id, parent string) (int64, error) {
+	args := &graphDriverRequest{
+		ID:     id,
+		Parent: parent,
+	}
+	var ret graphDriverResponse
+	if err := d.client.Call("GraphDriver.DiffSize", args, &ret); err != nil {
+		return -1, err
+	}
+	if ret.Err != "" {
+		return -1, errors.New(ret.Err)
+	}
+	return ret.Size, nil
+}

vendor/src/github.com/containers/storage/drivers/register/register_aufs.go

@@ -0,0 +1,8 @@
+// +build !exclude_graphdriver_aufs,linux
+
+package register
+
+import (
+	// register the aufs graphdriver
+	_ "github.com/containers/storage/drivers/aufs"
+)

vendor/src/github.com/containers/storage/drivers/register/register_btrfs.go

@@ -0,0 +1,8 @@
+// +build !exclude_graphdriver_btrfs,linux
+
+package register
+
+import (
+	// register the btrfs graphdriver
+	_ "github.com/containers/storage/drivers/btrfs"
+)

vendor/src/github.com/containers/storage/drivers/register/register_devicemapper.go

@@ -0,0 +1,8 @@
+// +build !exclude_graphdriver_devicemapper,linux
+
+package register
+
+import (
+	// register the devmapper graphdriver
+	_ "github.com/containers/storage/drivers/devmapper"
+)

vendor/src/github.com/containers/storage/drivers/register/register_overlay.go

@@ -0,0 +1,9 @@
+// +build !exclude_graphdriver_overlay,linux
+
+package register
+
+import (
+	// register the overlay graphdriver
+	_ "github.com/containers/storage/drivers/overlay"
+	_ "github.com/containers/storage/drivers/overlay2"
+)

vendor/src/github.com/containers/storage/drivers/register/register_vfs.go

@@ -0,0 +1,6 @@
+package register
+
+import (
+	// register vfs
+	_ "github.com/containers/storage/drivers/vfs"
+)

vendor/src/github.com/containers/storage/drivers/register/register_windows.go

@@ -0,0 +1,6 @@
+package register
+
+import (
+	// register the windows graph driver
+	_ "github.com/containers/storage/drivers/windows"
+)

vendor/src/github.com/containers/storage/drivers/register/register_zfs.go

@@ -0,0 +1,8 @@
+// +build !exclude_graphdriver_zfs,linux !exclude_graphdriver_zfs,freebsd, solaris
+
+package register
+
+import (
+	// register the zfs driver
+	_ "github.com/containers/storage/drivers/zfs"
+)

vendor/src/github.com/containers/storage/drivers/vfs/driver.go

@@ -0,0 +1,145 @@
+package vfs
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/containers/storage/drivers"
+	"github.com/containers/storage/pkg/chrootarchive"
+	"github.com/containers/storage/pkg/idtools"
+
+	"github.com/opencontainers/runc/libcontainer/label"
+)
+
+var (
+	// CopyWithTar defines the copy method to use.
+	CopyWithTar = chrootarchive.CopyWithTar
+)
+
+func init() {
+	graphdriver.Register("vfs", Init)
+}
+
+// Init returns a new VFS driver.
+// This sets the home directory for the driver and returns NaiveDiffDriver.
+func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
+	d := &Driver{
+		home:    home,
+		uidMaps: uidMaps,
+		gidMaps: gidMaps,
+	}
+	rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
+	if err != nil {
+		return nil, err
+	}
+	if err := idtools.MkdirAllAs(home, 0700, rootUID, rootGID); err != nil {
+		return nil, err
+	}
+	return graphdriver.NewNaiveDiffDriver(d, uidMaps, gidMaps), nil
+}
+
+// Driver holds information about the driver, home directory of the driver.
+// Driver implements graphdriver.ProtoDriver. It uses only basic vfs operations.
+// In order to support layering, files are copied from the parent layer into the new layer. There is no copy-on-write support.
+// Driver must be wrapped in NaiveDiffDriver to be used as a graphdriver.Driver
+type Driver struct {
+	home    string
+	uidMaps []idtools.IDMap
+	gidMaps []idtools.IDMap
+}
+
+func (d *Driver) String() string {
+	return "vfs"
+}
+
+// Status is used for implementing the graphdriver.ProtoDriver interface. VFS does not currently have any status information.
+func (d *Driver) Status() [][2]string {
+	return nil
+}
+
+// GetMetadata is used for implementing the graphdriver.ProtoDriver interface. VFS does not currently have any meta data.
+func (d *Driver) GetMetadata(id string) (map[string]string, error) {
+	return nil, nil
+}
+
+// Cleanup is used to implement graphdriver.ProtoDriver. There is no cleanup required for this driver.
+func (d *Driver) Cleanup() error {
+	return nil
+}
+
+// CreateReadWrite creates a layer that is writable for use as a container
+// file system.
+func (d *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	return d.Create(id, parent, mountLabel, storageOpt)
+}
+
+// Create prepares the filesystem for the VFS driver and copies the directory for the given id under the parent.
+func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]string) error {
+	if len(storageOpt) != 0 {
+		return fmt.Errorf("--storage-opt is not supported for vfs")
+	}
+
+	dir := d.dir(id)
+	rootUID, rootGID, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		return err
+	}
+	if err := idtools.MkdirAllAs(filepath.Dir(dir), 0700, rootUID, rootGID); err != nil {
+		return err
+	}
+	if err := idtools.MkdirAs(dir, 0755, rootUID, rootGID); err != nil {
+		return err
+	}
+	opts := []string{"level:s0"}
+	if _, mountLabel, err := label.InitLabels(opts); err == nil {
+		label.SetFileLabel(dir, mountLabel)
+	}
+	if parent == "" {
+		return nil
+	}
+	parentDir, err := d.Get(parent, "")
+	if err != nil {
+		return fmt.Errorf("%s: %s", parent, err)
+	}
+	if err := CopyWithTar(parentDir, dir); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (d *Driver) dir(id string) string {
+	return filepath.Join(d.home, "dir", filepath.Base(id))
+}
+
+// Remove deletes the content from the directory for a given id.
+func (d *Driver) Remove(id string) error {
+	if err := os.RemoveAll(d.dir(id)); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	return nil
+}
+
+// Get returns the directory for the given id.
+func (d *Driver) Get(id, mountLabel string) (string, error) {
+	dir := d.dir(id)
+	if st, err := os.Stat(dir); err != nil {
+		return "", err
+	} else if !st.IsDir() {
+		return "", fmt.Errorf("%s: not a directory", dir)
+	}
+	return dir, nil
+}
+
+// Put is a noop for vfs that return nil for the error, since this driver has no runtime resources to clean up.
+func (d *Driver) Put(id string) error {
+	// The vfs driver has no runtime resources (e.g. mounts)
+	// to clean up, so we don't need anything here
+	return nil
+}
+
+// Exists checks to see if the directory exists for the given id.
+func (d *Driver) Exists(id string) bool {
+	_, err := os.Stat(d.dir(id))
+	return err == nil
+}

vendor/src/github.com/containers/storage/drivers/zfs/MAINTAINERS

@@ -0,0 +1,2 @@
+Jörg Thalheim <joerg@higgsboson.tk> (@Mic92)
+Arthur Gautier <baloo@gandi.net> (@baloose)

vendor/src/github.com/containers/storage/drivers/zfs/zfs.go

@@ -0,0 +1,405 @@
+// +build linux freebsd solaris
+
+package zfs
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path"
+	"strconv"
+	"strings"
+	"sync"
+	"syscall"
+	"time"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/storage/drivers"
+	"github.com/containers/storage/pkg/idtools"
+	"github.com/containers/storage/pkg/mount"
+	"github.com/containers/storage/pkg/parsers"
+	zfs "github.com/mistifyio/go-zfs"
+	"github.com/opencontainers/runc/libcontainer/label"
+)
+
+type zfsOptions struct {
+	fsName    string
+	mountPath string
+}
+
+func init() {
+	graphdriver.Register("zfs", Init)
+}
+
+// Logger returns a zfs logger implementation.
+type Logger struct{}
+
+// Log wraps log message from ZFS driver with a prefix '[zfs]'.
+func (*Logger) Log(cmd []string) {
+	logrus.Debugf("[zfs] %s", strings.Join(cmd, " "))
+}
+
+// Init returns a new ZFS driver.
+// It takes base mount path and an array of options which are represented as key value pairs.
+// Each option is in the for key=value. 'zfs.fsname' is expected to be a valid key in the options.
+func Init(base string, opt []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
+	var err error
+
+	if _, err := exec.LookPath("zfs"); err != nil {
+		logrus.Debugf("[zfs] zfs command is not available: %v", err)
+		return nil, graphdriver.ErrPrerequisites
+	}
+
+	file, err := os.OpenFile("/dev/zfs", os.O_RDWR, 600)
+	if err != nil {
+		logrus.Debugf("[zfs] cannot open /dev/zfs: %v", err)
+		return nil, graphdriver.ErrPrerequisites
+	}
+	defer file.Close()
+
+	options, err := parseOptions(opt)
+	if err != nil {
+		return nil, err
+	}
+	options.mountPath = base
+
+	rootdir := path.Dir(base)
+
+	if options.fsName == "" {
+		err = checkRootdirFs(rootdir)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if options.fsName == "" {
+		options.fsName, err = lookupZfsDataset(rootdir)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	zfs.SetLogger(new(Logger))
+
+	filesystems, err := zfs.Filesystems(options.fsName)
+	if err != nil {
+		return nil, fmt.Errorf("Cannot find root filesystem %s: %v", options.fsName, err)
+	}
+
+	filesystemsCache := make(map[string]bool, len(filesystems))
+	var rootDataset *zfs.Dataset
+	for _, fs := range filesystems {
+		if fs.Name == options.fsName {
+			rootDataset = fs
+		}
+		filesystemsCache[fs.Name] = true
+	}
+
+	if rootDataset == nil {
+		return nil, fmt.Errorf("BUG: zfs get all -t filesystem -rHp '%s' should contain '%s'", options.fsName, options.fsName)
+	}
+
+	if err := mount.MakePrivate(base); err != nil {
+		return nil, err
+	}
+	d := &Driver{
+		dataset:          rootDataset,
+		options:          options,
+		filesystemsCache: filesystemsCache,
+		uidMaps:          uidMaps,
+		gidMaps:          gidMaps,
+		ctr:              graphdriver.NewRefCounter(graphdriver.NewDefaultChecker()),
+	}
+	return graphdriver.NewNaiveDiffDriver(d, uidMaps, gidMaps), nil
+}
+
+func parseOptions(opt []string) (zfsOptions, error) {
+	var options zfsOptions
+	options.fsName = ""
+	for _, option := range opt {
+		key, val, err := parsers.ParseKeyValueOpt(option)
+		if err != nil {
+			return options, err
+		}
+		key = strings.ToLower(key)
+		switch key {
+		case "zfs.fsname":
+			options.fsName = val
+		default:
+			return options, fmt.Errorf("Unknown option %s", key)
+		}
+	}
+	return options, nil
+}
+
+func lookupZfsDataset(rootdir string) (string, error) {
+	var stat syscall.Stat_t
+	if err := syscall.Stat(rootdir, &stat); err != nil {
+		return "", fmt.Errorf("Failed to access '%s': %s", rootdir, err)
+	}
+	wantedDev := stat.Dev
+
+	mounts, err := mount.GetMounts()
+	if err != nil {
+		return "", err
+	}
+	for _, m := range mounts {
+		if err := syscall.Stat(m.Mountpoint, &stat); err != nil {
+			logrus.Debugf("[zfs] failed to stat '%s' while scanning for zfs mount: %v", m.Mountpoint, err)
+			continue // may fail on fuse file systems
+		}
+
+		if stat.Dev == wantedDev && m.Fstype == "zfs" {
+			return m.Source, nil
+		}
+	}
+
+	return "", fmt.Errorf("Failed to find zfs dataset mounted on '%s' in /proc/mounts", rootdir)
+}
+
+// Driver holds information about the driver, such as zfs dataset, options and cache.
+type Driver struct {
+	dataset          *zfs.Dataset
+	options          zfsOptions
+	sync.Mutex       // protects filesystem cache against concurrent access
+	filesystemsCache map[string]bool
+	uidMaps          []idtools.IDMap
+	gidMaps          []idtools.IDMap
+	ctr              *graphdriver.RefCounter
+}
+
+func (d *Driver) String() string {
+	return "zfs"
+}
+
+// Cleanup is used to implement graphdriver.ProtoDriver. There is no cleanup required for this driver.
+func (d *Driver) Cleanup() error {
+	return nil
+}
+
+// Status returns information about the ZFS filesystem. It returns a two dimensional array of information
+// such as pool name, dataset name, disk usage, parent quota and compression used.
+// Currently it return 'Zpool', 'Zpool Health', 'Parent Dataset', 'Space Used By Parent',
+// 'Space Available', 'Parent Quota' and 'Compression'.
+func (d *Driver) Status() [][2]string {
+	parts := strings.Split(d.dataset.Name, "/")
+	pool, err := zfs.GetZpool(parts[0])
+
+	var poolName, poolHealth string
+	if err == nil {
+		poolName = pool.Name
+		poolHealth = pool.Health
+	} else {
+		poolName = fmt.Sprintf("error while getting pool information %v", err)
+		poolHealth = "not available"
+	}
+
+	quota := "no"
+	if d.dataset.Quota != 0 {
+		quota = strconv.FormatUint(d.dataset.Quota, 10)
+	}
+
+	return [][2]string{
+		{"Zpool", poolName},
+		{"Zpool Health", poolHealth},
+		{"Parent Dataset", d.dataset.Name},
+		{"Space Used By Parent", strconv.FormatUint(d.dataset.Used, 10)},
+		{"Space Available", strconv.FormatUint(d.dataset.Avail, 10)},
+		{"Parent Quota", quota},
+		{"Compression", d.dataset.Compression},
+	}
+}
+
+// GetMetadata returns image/container metadata related to graph driver
+func (d *Driver) GetMetadata(id string) (map[string]string, error) {
+	return nil, nil
+}
+
+func (d *Driver) cloneFilesystem(name, parentName string) error {
+	snapshotName := fmt.Sprintf("%d", time.Now().Nanosecond())
+	parentDataset := zfs.Dataset{Name: parentName}
+	snapshot, err := parentDataset.Snapshot(snapshotName /*recursive */, false)
+	if err != nil {
+		return err
+	}
+
+	_, err = snapshot.Clone(name, map[string]string{"mountpoint": "legacy"})
+	if err == nil {
+		d.Lock()
+		d.filesystemsCache[name] = true
+		d.Unlock()
+	}
+
+	if err != nil {
+		snapshot.Destroy(zfs.DestroyDeferDeletion)
+		return err
+	}
+	return snapshot.Destroy(zfs.DestroyDeferDeletion)
+}
+
+func (d *Driver) zfsPath(id string) string {
+	return d.options.fsName + "/" + id
+}
+
+func (d *Driver) mountPath(id string) string {
+	return path.Join(d.options.mountPath, "graph", getMountpoint(id))
+}
+
+// CreateReadWrite creates a layer that is writable for use as a container
+// file system.
+func (d *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[string]string) error {
+	return d.Create(id, parent, mountLabel, storageOpt)
+}
+
+// Create prepares the dataset and filesystem for the ZFS driver for the given id under the parent.
+func (d *Driver) Create(id string, parent string, mountLabel string, storageOpt map[string]string) error {
+	err := d.create(id, parent, storageOpt)
+	if err == nil {
+		return nil
+	}
+	if zfsError, ok := err.(*zfs.Error); ok {
+		if !strings.HasSuffix(zfsError.Stderr, "dataset already exists\n") {
+			return err
+		}
+		// aborted build -> cleanup
+	} else {
+		return err
+	}
+
+	dataset := zfs.Dataset{Name: d.zfsPath(id)}
+	if err := dataset.Destroy(zfs.DestroyRecursiveClones); err != nil {
+		return err
+	}
+
+	// retry
+	return d.create(id, parent, storageOpt)
+}
+
+func (d *Driver) create(id, parent string, storageOpt map[string]string) error {
+	name := d.zfsPath(id)
+	quota, err := parseStorageOpt(storageOpt)
+	if err != nil {
+		return err
+	}
+	if parent == "" {
+		mountoptions := map[string]string{"mountpoint": "legacy"}
+		fs, err := zfs.CreateFilesystem(name, mountoptions)
+		if err == nil {
+			err = setQuota(name, quota)
+			if err == nil {
+				d.Lock()
+				d.filesystemsCache[fs.Name] = true
+				d.Unlock()
+			}
+		}
+		return err
+	}
+	err = d.cloneFilesystem(name, d.zfsPath(parent))
+	if err == nil {
+		err = setQuota(name, quota)
+	}
+	return err
+}
+
+func parseStorageOpt(storageOpt map[string]string) (string, error) {
+	// Read size to change the disk quota per container
+	for k, v := range storageOpt {
+		key := strings.ToLower(k)
+		switch key {
+		case "size":
+			return v, nil
+		default:
+			return "0", fmt.Errorf("Unknown option %s", key)
+		}
+	}
+	return "0", nil
+}
+
+func setQuota(name string, quota string) error {
+	if quota == "0" {
+		return nil
+	}
+	fs, err := zfs.GetDataset(name)
+	if err != nil {
+		return err
+	}
+	return fs.SetProperty("quota", quota)
+}
+
+// Remove deletes the dataset, filesystem and the cache for the given id.
+func (d *Driver) Remove(id string) error {
+	name := d.zfsPath(id)
+	dataset := zfs.Dataset{Name: name}
+	err := dataset.Destroy(zfs.DestroyRecursive)
+	if err == nil {
+		d.Lock()
+		delete(d.filesystemsCache, name)
+		d.Unlock()
+	}
+	return err
+}
+
+// Get returns the mountpoint for the given id after creating the target directories if necessary.
+func (d *Driver) Get(id, mountLabel string) (string, error) {
+	mountpoint := d.mountPath(id)
+	if count := d.ctr.Increment(mountpoint); count > 1 {
+		return mountpoint, nil
+	}
+
+	filesystem := d.zfsPath(id)
+	options := label.FormatMountLabel("", mountLabel)
+	logrus.Debugf(`[zfs] mount("%s", "%s", "%s")`, filesystem, mountpoint, options)
+
+	rootUID, rootGID, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
+	if err != nil {
+		d.ctr.Decrement(mountpoint)
+		return "", err
+	}
+	// Create the target directories if they don't exist
+	if err := idtools.MkdirAllAs(mountpoint, 0755, rootUID, rootGID); err != nil {
+		d.ctr.Decrement(mountpoint)
+		return "", err
+	}
+
+	if err := mount.Mount(filesystem, mountpoint, "zfs", options); err != nil {
+		d.ctr.Decrement(mountpoint)
+		return "", fmt.Errorf("error creating zfs mount of %s to %s: %v", filesystem, mountpoint, err)
+	}
+
+	// this could be our first mount after creation of the filesystem, and the root dir may still have root
+	// permissions instead of the remapped root uid:gid (if user namespaces are enabled):
+	if err := os.Chown(mountpoint, rootUID, rootGID); err != nil {
+		mount.Unmount(mountpoint)
+		d.ctr.Decrement(mountpoint)
+		return "", fmt.Errorf("error modifying zfs mountpoint (%s) directory ownership: %v", mountpoint, err)
+	}
+
+	return mountpoint, nil
+}
+
+// Put removes the existing mountpoint for the given id if it exists.
+func (d *Driver) Put(id string) error {
+	mountpoint := d.mountPath(id)
+	if count := d.ctr.Decrement(mountpoint); count > 0 {
+		return nil
+	}
+	mounted, err := graphdriver.Mounted(graphdriver.FsMagicZfs, mountpoint)
+	if err != nil || !mounted {
+		return err
+	}
+
+	logrus.Debugf(`[zfs] unmount("%s")`, mountpoint)
+
+	err = mount.Unmount(mountpoint)
+	if err != nil {
+		return fmt.Errorf("error unmounting to %s: %v", mountpoint, err)
+	}
+	return err
+}
+
+// Exists checks to see if the cache entry exists for the given id.
+func (d *Driver) Exists(id string) bool {
+	d.Lock()
+	defer d.Unlock()
+	return d.filesystemsCache[d.zfsPath(id)] == true
+}

vendor/src/github.com/containers/storage/drivers/zfs/zfs_freebsd.go

@@ -0,0 +1,38 @@
+package zfs
+
+import (
+	"fmt"
+	"strings"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/storage/drivers"
+)
+
+func checkRootdirFs(rootdir string) error {
+	var buf syscall.Statfs_t
+	if err := syscall.Statfs(rootdir, &buf); err != nil {
+		return fmt.Errorf("Failed to access '%s': %s", rootdir, err)
+	}
+
+	// on FreeBSD buf.Fstypename contains ['z', 'f', 's', 0 ... ]
+	if (buf.Fstypename[0] != 122) || (buf.Fstypename[1] != 102) || (buf.Fstypename[2] != 115) || (buf.Fstypename[3] != 0) {
+		logrus.Debugf("[zfs] no zfs dataset found for rootdir '%s'", rootdir)
+		return graphdriver.ErrPrerequisites
+	}
+
+	return nil
+}
+
+func getMountpoint(id string) string {
+	maxlen := 12
+
+	// we need to preserve filesystem suffix
+	suffix := strings.SplitN(id, "-", 2)
+
+	if len(suffix) > 1 {
+		return id[:maxlen] + "-" + suffix[1]
+	}
+
+	return id[:maxlen]
+}

vendor/src/github.com/containers/storage/drivers/zfs/zfs_linux.go

@@ -0,0 +1,27 @@
+package zfs
+
+import (
+	"fmt"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/storage/drivers"
+)
+
+func checkRootdirFs(rootdir string) error {
+	var buf syscall.Statfs_t
+	if err := syscall.Statfs(rootdir, &buf); err != nil {
+		return fmt.Errorf("Failed to access '%s': %s", rootdir, err)
+	}
+
+	if graphdriver.FsMagic(buf.Type) != graphdriver.FsMagicZfs {
+		logrus.Debugf("[zfs] no zfs dataset found for rootdir '%s'", rootdir)
+		return graphdriver.ErrPrerequisites
+	}
+
+	return nil
+}
+
+func getMountpoint(id string) string {
+	return id
+}

vendor/src/github.com/containers/storage/drivers/zfs/zfs_solaris.go

@@ -0,0 +1,59 @@
+// +build solaris,cgo
+
+package zfs
+
+/*
+#include <sys/statvfs.h>
+#include <stdlib.h>
+
+static inline struct statvfs *getstatfs(char *s) {
+        struct statvfs *buf;
+        int err;
+        buf = (struct statvfs *)malloc(sizeof(struct statvfs));
+        err = statvfs(s, buf);
+        return buf;
+}
+*/
+import "C"
+import (
+	"path/filepath"
+	"strings"
+	"unsafe"
+
+	log "github.com/Sirupsen/logrus"
+	"github.com/containers/storage/drivers"
+)
+
+func checkRootdirFs(rootdir string) error {
+
+	cs := C.CString(filepath.Dir(rootdir))
+	buf := C.getstatfs(cs)
+
+	// on Solaris buf.f_basetype contains ['z', 'f', 's', 0 ... ]
+	if (buf.f_basetype[0] != 122) || (buf.f_basetype[1] != 102) || (buf.f_basetype[2] != 115) ||
+		(buf.f_basetype[3] != 0) {
+		log.Debugf("[zfs] no zfs dataset found for rootdir '%s'", rootdir)
+		C.free(unsafe.Pointer(buf))
+		return graphdriver.ErrPrerequisites
+	}
+
+	C.free(unsafe.Pointer(buf))
+	C.free(unsafe.Pointer(cs))
+	return nil
+}
+
+/* rootfs is introduced to comply with the OCI spec
+which states that root filesystem must be mounted at <CID>/rootfs/ instead of <CID>/
+*/
+func getMountpoint(id string) string {
+	maxlen := 12
+
+	// we need to preserve filesystem suffix
+	suffix := strings.SplitN(id, "-", 2)
+
+	if len(suffix) > 1 {
+		return filepath.Join(id[:maxlen]+"-"+suffix[1], "rootfs", "root")
+	}
+
+	return filepath.Join(id[:maxlen], "rootfs", "root")
+}

vendor/src/github.com/containers/storage/drivers/zfs/zfs_unsupported.go

@@ -0,0 +1,11 @@
+// +build !linux,!freebsd,!solaris
+
+package zfs
+
+func checkRootdirFs(rootdir string) error {
+	return nil
+}
+
+func getMountpoint(id string) string {
+	return id
+}

vendor/src/github.com/containers/storage/pkg/archive/archive_linux.go

@@ -0,0 +1,91 @@
+package archive
+
+import (
+	"archive/tar"
+	"os"
+	"path/filepath"
+	"strings"
+	"syscall"
+
+	"github.com/containers/storage/pkg/system"
+)
+
+func getWhiteoutConverter(format WhiteoutFormat) tarWhiteoutConverter {
+	if format == OverlayWhiteoutFormat {
+		return overlayWhiteoutConverter{}
+	}
+	return nil
+}
+
+type overlayWhiteoutConverter struct{}
+
+func (overlayWhiteoutConverter) ConvertWrite(hdr *tar.Header, path string, fi os.FileInfo) error {
+	// convert whiteouts to AUFS format
+	if fi.Mode()&os.ModeCharDevice != 0 && hdr.Devmajor == 0 && hdr.Devminor == 0 {
+		// we just rename the file and make it normal
+		dir, filename := filepath.Split(hdr.Name)
+		hdr.Name = filepath.Join(dir, WhiteoutPrefix+filename)
+		hdr.Mode = 0600
+		hdr.Typeflag = tar.TypeReg
+		hdr.Size = 0
+	}
+
+	if fi.Mode()&os.ModeDir != 0 {
+		// convert opaque dirs to AUFS format by writing an empty file with the prefix
+		opaque, err := system.Lgetxattr(path, "trusted.overlay.opaque")
+		if err != nil {
+			return err
+		}
+		if opaque != nil && len(opaque) == 1 && opaque[0] == 'y' {
+			// create a header for the whiteout file
+			// it should inherit some properties from the parent, but be a regular file
+			*hdr = tar.Header{
+				Typeflag:   tar.TypeReg,
+				Mode:       hdr.Mode & int64(os.ModePerm),
+				Name:       filepath.Join(hdr.Name, WhiteoutOpaqueDir),
+				Size:       0,
+				Uid:        hdr.Uid,
+				Uname:      hdr.Uname,
+				Gid:        hdr.Gid,
+				Gname:      hdr.Gname,
+				AccessTime: hdr.AccessTime,
+				ChangeTime: hdr.ChangeTime,
+			}
+		}
+	}
+
+	return nil
+}
+
+func (overlayWhiteoutConverter) ConvertRead(hdr *tar.Header, path string) (bool, error) {
+	base := filepath.Base(path)
+	dir := filepath.Dir(path)
+
+	// if a directory is marked as opaque by the AUFS special file, we need to translate that to overlay
+	if base == WhiteoutOpaqueDir {
+		if err := syscall.Setxattr(dir, "trusted.overlay.opaque", []byte{'y'}, 0); err != nil {
+			return false, err
+		}
+
+		// don't write the file itself
+		return false, nil
+	}
+
+	// if a file was deleted and we are using overlay, we need to create a character device
+	if strings.HasPrefix(base, WhiteoutPrefix) {
+		originalBase := base[len(WhiteoutPrefix):]
+		originalPath := filepath.Join(dir, originalBase)
+
+		if err := syscall.Mknod(originalPath, syscall.S_IFCHR, 0); err != nil {
+			return false, err
+		}
+		if err := os.Chown(originalPath, hdr.Uid, hdr.Gid); err != nil {
+			return false, err
+		}
+
+		// don't write the file itself
+		return false, nil
+	}
+
+	return true, nil
+}