cri-o/vendor/github.com/containers/image/ostree/ostree_transport.go
Antonio Murdaca 22f96b1806
fix issue with official images and manifest lits
Signed-off-by: Antonio Murdaca <runcom@redhat.com>
2017-09-13 19:01:06 +02:00

226 lines
8.1 KiB
Go

// +build !containers_image_ostree_stub
package ostree
import (
"bytes"
"fmt"
"os"
"path/filepath"
"regexp"
"strings"
"github.com/pkg/errors"
"github.com/containers/image/directory/explicitfilepath"
"github.com/containers/image/docker/reference"
"github.com/containers/image/transports"
"github.com/containers/image/types"
)
const defaultOSTreeRepo = "/ostree/repo"
// Transport is an ImageTransport for ostree paths.
var Transport = ostreeTransport{}
type ostreeTransport struct{}
func (t ostreeTransport) Name() string {
return "ostree"
}
func init() {
transports.Register(Transport)
}
// 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 ostreeTransport) ValidatePolicyConfigurationScope(scope string) error {
sep := strings.Index(scope, ":")
if sep < 0 {
return errors.Errorf("Invalid ostree: scope %s: Must include a repo", scope)
}
repo := scope[:sep]
if !strings.HasPrefix(repo, "/") {
return errors.Errorf("Invalid ostree: scope %s: repository must be an absolute path", scope)
}
cleaned := filepath.Clean(repo)
if cleaned != repo {
return errors.Errorf(`Invalid ostree: scope %s: Uses non-canonical path format, perhaps try with path %s`, scope, cleaned)
}
// FIXME? In the namespaces within a repo,
// we could be verifying the various character set and length restrictions
// from docker/distribution/reference.regexp.go, but other than that there
// are few semantically invalid strings.
return nil
}
// ostreeReference is an ImageReference for ostree paths.
type ostreeReference struct {
image string
branchName string
repo string
}
func (t ostreeTransport) ParseReference(ref string) (types.ImageReference, error) {
var repo = ""
var image = ""
s := strings.SplitN(ref, "@/", 2)
if len(s) == 1 {
image, repo = s[0], defaultOSTreeRepo
} else {
image, repo = s[0], "/"+s[1]
}
return NewReference(image, repo)
}
// NewReference returns an OSTree reference for a specified repo and image.
func NewReference(image string, repo string) (types.ImageReference, error) {
// image is not _really_ in a containers/image/docker/reference format;
// as far as the libOSTree ociimage/* namespace is concerned, it is more or
// less an arbitrary string with an implied tag.
// Parse the image using reference.ParseNormalizedNamed so that we can
// check whether the images has a tag specified and we can add ":latest" if needed
ostreeImage, err := reference.ParseNormalizedNamed(image)
if err != nil {
return nil, err
}
if reference.IsNameOnly(ostreeImage) {
image = image + ":latest"
}
resolved, err := explicitfilepath.ResolvePathToFullyExplicit(repo)
if err != nil {
// With os.IsNotExist(err), the parent directory of repo is also not existent;
// that should ordinarily not happen, but it would be a bit weird to reject
// references which do not specify a repo just because the implicit defaultOSTreeRepo
// does not exist.
if os.IsNotExist(err) && repo == defaultOSTreeRepo {
resolved = repo
} else {
return nil, err
}
}
// This is necessary to prevent directory paths returned by PolicyConfigurationNamespaces
// from being ambiguous with values of PolicyConfigurationIdentity.
if strings.Contains(resolved, ":") {
return nil, errors.Errorf("Invalid OSTreeCI reference %s@%s: path %s contains a colon", image, repo, resolved)
}
return ostreeReference{
image: image,
branchName: encodeOStreeRef(image),
repo: resolved,
}, nil
}
func (ref ostreeReference) 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.
func (ref ostreeReference) StringWithinTransport() string {
return fmt.Sprintf("%s@%s", ref.image, ref.repo)
}
// 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 ostreeReference) DockerReference() reference.Named {
return nil
}
func (ref ostreeReference) PolicyConfigurationIdentity() string {
return fmt.Sprintf("%s:%s", ref.repo, ref.image)
}
// 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 ostreeReference) PolicyConfigurationNamespaces() []string {
s := strings.SplitN(ref.image, ":", 2)
if len(s) != 2 { // Coverage: Should never happen, NewReference above ensures ref.image has a :tag.
panic(fmt.Sprintf("Internal inconsistency: ref.image value %q does not have a :tag", ref.image))
}
name := s[0]
res := []string{}
for {
res = append(res, fmt.Sprintf("%s:%s", ref.repo, name))
lastSlash := strings.LastIndex(name, "/")
if lastSlash == -1 {
break
}
name = name[:lastSlash]
}
return res
}
// 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 ostreeReference) NewImage(ctx *types.SystemContext) (types.Image, error) {
return nil, errors.New("Reading ostree: images is currently not supported")
}
// NewImageSource returns a types.ImageSource for this reference.
// The caller must call .Close() on the returned ImageSource.
func (ref ostreeReference) NewImageSource(ctx *types.SystemContext) (types.ImageSource, error) {
return nil, errors.New("Reading ostree: images is currently not supported")
}
// NewImageDestination returns a types.ImageDestination for this reference.
// The caller must call .Close() on the returned ImageDestination.
func (ref ostreeReference) NewImageDestination(ctx *types.SystemContext) (types.ImageDestination, error) {
var tmpDir string
if ctx == nil || ctx.OSTreeTmpDirPath == "" {
tmpDir = os.TempDir()
} else {
tmpDir = ctx.OSTreeTmpDirPath
}
return newImageDestination(ref, tmpDir)
}
// DeleteImage deletes the named image from the registry, if supported.
func (ref ostreeReference) DeleteImage(ctx *types.SystemContext) error {
return errors.Errorf("Deleting images not implemented for ostree: images")
}
var ostreeRefRegexp = regexp.MustCompile(`^[A-Za-z0-9.-]$`)
func encodeOStreeRef(in string) string {
var buffer bytes.Buffer
for i := range in {
sub := in[i : i+1]
if ostreeRefRegexp.MatchString(sub) {
buffer.WriteString(sub)
} else {
buffer.WriteString(fmt.Sprintf("_%02X", sub[0]))
}
}
return buffer.String()
}
// manifestPath returns a path for the manifest within a ostree using our conventions.
func (ref ostreeReference) manifestPath() string {
return filepath.Join("manifest", "manifest.json")
}
// signaturePath returns a path for a signature within a ostree using our conventions.
func (ref ostreeReference) signaturePath(index int) string {
return filepath.Join("manifest", fmt.Sprintf("signature-%d", index+1))
}