Move manifest package to schema1

As we begin our march towards multi-arch, we must prepare for the reality of
multiple manifest schemas. This is the beginning of a set of changes to
facilitate this. We are both moving this package into its target position where
it may live peacefully next to other manfiest versions.

Signed-off-by: Stephen J Day <stephen.day@docker.com>
This commit is contained in:
Stephen J Day 2015-08-20 21:24:30 -07:00
parent 8c3fc2619c
commit 6712e602b0
22 changed files with 120 additions and 106 deletions

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package schema1
import (
"encoding/json"
"github.com/docker/distribution/digest"
"github.com/docker/distribution/manifest"
"github.com/docker/libtrust"
)
// TODO(stevvooe): When we rev the manifest format, the contents of this
// package should be moved to manifest/v1.
const (
// ManifestMediaType specifies the mediaType for the current version. Note
// that for schema version 1, the the media is optionally
// "application/json".
ManifestMediaType = "application/vnd.docker.distribution.manifest.v1+json"
)
var (
// SchemaVersion provides a pre-initialized version structure for this
// packages version of the manifest.
SchemaVersion = manifest.Versioned{
SchemaVersion: 1,
}
)
// Manifest provides the base accessible fields for working with V2 image
// format in the registry.
type Manifest struct {
manifest.Versioned
// Name is the name of the image's repository
Name string `json:"name"`
// Tag is the tag of the image specified by this manifest
Tag string `json:"tag"`
// Architecture is the host architecture on which this image is intended to
// run
Architecture string `json:"architecture"`
// FSLayers is a list of filesystem layer blobSums contained in this image
FSLayers []FSLayer `json:"fsLayers"`
// History is a list of unstructured historical data for v1 compatibility
History []History `json:"history"`
}
// SignedManifest provides an envelope for a signed image manifest, including
// the format sensitive raw bytes. It contains fields to
type SignedManifest struct {
Manifest
// Raw is the byte representation of the ImageManifest, used for signature
// verification. The value of Raw must be used directly during
// serialization, or the signature check will fail. The manifest byte
// representation cannot change or it will have to be re-signed.
Raw []byte `json:"-"`
}
// UnmarshalJSON populates a new ImageManifest struct from JSON data.
func (sm *SignedManifest) UnmarshalJSON(b []byte) error {
var manifest Manifest
if err := json.Unmarshal(b, &manifest); err != nil {
return err
}
sm.Manifest = manifest
sm.Raw = make([]byte, len(b), len(b))
copy(sm.Raw, b)
return nil
}
// Payload returns the raw, signed content of the signed manifest. The
// contents can be used to calculate the content identifier.
func (sm *SignedManifest) Payload() ([]byte, error) {
jsig, err := libtrust.ParsePrettySignature(sm.Raw, "signatures")
if err != nil {
return nil, err
}
// Resolve the payload in the manifest.
return jsig.Payload()
}
// Signatures returns the signatures as provided by
// (*libtrust.JSONSignature).Signatures. The byte slices are opaque jws
// signatures.
func (sm *SignedManifest) Signatures() ([][]byte, error) {
jsig, err := libtrust.ParsePrettySignature(sm.Raw, "signatures")
if err != nil {
return nil, err
}
// Resolve the payload in the manifest.
return jsig.Signatures()
}
// MarshalJSON returns the contents of raw. If Raw is nil, marshals the inner
// contents. Applications requiring a marshaled signed manifest should simply
// use Raw directly, since the the content produced by json.Marshal will be
// compacted and will fail signature checks.
func (sm *SignedManifest) MarshalJSON() ([]byte, error) {
if len(sm.Raw) > 0 {
return sm.Raw, nil
}
// If the raw data is not available, just dump the inner content.
return json.Marshal(&sm.Manifest)
}
// FSLayer is a container struct for BlobSums defined in an image manifest
type FSLayer struct {
// BlobSum is the tarsum of the referenced filesystem image layer
BlobSum digest.Digest `json:"blobSum"`
}
// History stores unstructured v1 compatibility information
type History struct {
// V1Compatibility is the raw v1 compatibility information
V1Compatibility string `json:"v1Compatibility"`
}

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package schema1
import (
"bytes"
"encoding/json"
"reflect"
"testing"
"github.com/docker/libtrust"
)
type testEnv struct {
name, tag string
manifest *Manifest
signed *SignedManifest
pk libtrust.PrivateKey
}
func TestManifestMarshaling(t *testing.T) {
env := genEnv(t)
// Check that the Raw field is the same as json.MarshalIndent with these
// parameters.
p, err := json.MarshalIndent(env.signed, "", " ")
if err != nil {
t.Fatalf("error marshaling manifest: %v", err)
}
if !bytes.Equal(p, env.signed.Raw) {
t.Fatalf("manifest bytes not equal: %q != %q", string(env.signed.Raw), string(p))
}
}
func TestManifestUnmarshaling(t *testing.T) {
env := genEnv(t)
var signed SignedManifest
if err := json.Unmarshal(env.signed.Raw, &signed); err != nil {
t.Fatalf("error unmarshaling signed manifest: %v", err)
}
if !reflect.DeepEqual(&signed, env.signed) {
t.Fatalf("manifests are different after unmarshaling: %v != %v", signed, env.signed)
}
}
func TestManifestVerification(t *testing.T) {
env := genEnv(t)
publicKeys, err := Verify(env.signed)
if err != nil {
t.Fatalf("error verifying manifest: %v", err)
}
if len(publicKeys) == 0 {
t.Fatalf("no public keys found in signature")
}
var found bool
publicKey := env.pk.PublicKey()
// ensure that one of the extracted public keys matches the private key.
for _, candidate := range publicKeys {
if candidate.KeyID() == publicKey.KeyID() {
found = true
break
}
}
if !found {
t.Fatalf("expected public key, %v, not found in verified keys: %v", publicKey, publicKeys)
}
}
func genEnv(t *testing.T) *testEnv {
pk, err := libtrust.GenerateECP256PrivateKey()
if err != nil {
t.Fatalf("error generating test key: %v", err)
}
name, tag := "foo/bar", "test"
m := Manifest{
Versioned: SchemaVersion,
Name: name,
Tag: tag,
FSLayers: []FSLayer{
{
BlobSum: "asdf",
},
{
BlobSum: "qwer",
},
},
}
sm, err := Sign(&m, pk)
if err != nil {
t.Fatalf("error signing manifest: %v", err)
}
return &testEnv{
name: name,
tag: tag,
manifest: &m,
signed: sm,
pk: pk,
}
}

66
manifest/schema1/sign.go Normal file
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package schema1
import (
"crypto/x509"
"encoding/json"
"github.com/docker/libtrust"
)
// Sign signs the manifest with the provided private key, returning a
// SignedManifest. This typically won't be used within the registry, except
// for testing.
func Sign(m *Manifest, pk libtrust.PrivateKey) (*SignedManifest, error) {
p, err := json.MarshalIndent(m, "", " ")
if err != nil {
return nil, err
}
js, err := libtrust.NewJSONSignature(p)
if err != nil {
return nil, err
}
if err := js.Sign(pk); err != nil {
return nil, err
}
pretty, err := js.PrettySignature("signatures")
if err != nil {
return nil, err
}
return &SignedManifest{
Manifest: *m,
Raw: pretty,
}, nil
}
// SignWithChain signs the manifest with the given private key and x509 chain.
// The public key of the first element in the chain must be the public key
// corresponding with the sign key.
func SignWithChain(m *Manifest, key libtrust.PrivateKey, chain []*x509.Certificate) (*SignedManifest, error) {
p, err := json.MarshalIndent(m, "", " ")
if err != nil {
return nil, err
}
js, err := libtrust.NewJSONSignature(p)
if err != nil {
return nil, err
}
if err := js.SignWithChain(key, chain); err != nil {
return nil, err
}
pretty, err := js.PrettySignature("signatures")
if err != nil {
return nil, err
}
return &SignedManifest{
Manifest: *m,
Raw: pretty,
}, nil
}

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package schema1
import (
"crypto/x509"
"github.com/Sirupsen/logrus"
"github.com/docker/libtrust"
)
// Verify verifies the signature of the signed manifest returning the public
// keys used during signing.
func Verify(sm *SignedManifest) ([]libtrust.PublicKey, error) {
js, err := libtrust.ParsePrettySignature(sm.Raw, "signatures")
if err != nil {
logrus.WithField("err", err).Debugf("(*SignedManifest).Verify")
return nil, err
}
return js.Verify()
}
// VerifyChains verifies the signature of the signed manifest against the
// certificate pool returning the list of verified chains. Signatures without
// an x509 chain are not checked.
func VerifyChains(sm *SignedManifest, ca *x509.CertPool) ([][]*x509.Certificate, error) {
js, err := libtrust.ParsePrettySignature(sm.Raw, "signatures")
if err != nil {
return nil, err
}
return js.VerifyChains(ca)
}