distribution/storage/manifest.go
Stephen J Day e6e0219065 Avoid manifest verification errors by using Raw
Because json.Marshal does compaction on returned results, applications must
directly use SignedManifest.Raw when the marshaled value is required.
Otherwise, the returned manifest will fail signature checks.
2014-12-01 17:10:33 -08:00

210 lines
5.8 KiB
Go

package storage
import (
"crypto/x509"
"encoding/json"
"fmt"
"strings"
"github.com/Sirupsen/logrus"
"github.com/docker/libtrust"
"github.com/docker/docker-registry/digest"
)
// ErrUnknownManifest is returned if the manifest is not known by the
// registry.
type ErrUnknownManifest struct {
Name string
Tag string
}
func (err ErrUnknownManifest) Error() string {
return fmt.Sprintf("unknown manifest name=%s tag=%s", err.Name, err.Tag)
}
// ErrManifestUnverified is returned when the registry is unable to verify
// the manifest.
type ErrManifestUnverified struct{}
func (ErrManifestUnverified) Error() string {
return fmt.Sprintf("unverified manifest")
}
// ErrManifestVerification provides a type to collect errors encountered
// during manifest verification. Currently, it accepts errors of all types,
// but it may be narrowed to those involving manifest verification.
type ErrManifestVerification []error
func (errs ErrManifestVerification) Error() string {
var parts []string
for _, err := range errs {
parts = append(parts, err.Error())
}
return fmt.Sprintf("errors verifying manifest: %v", strings.Join(parts, ","))
}
// Versioned provides a struct with just the manifest schemaVersion. Incoming
// content with unknown schema version can be decoded against this struct to
// check the version.
type Versioned struct {
// SchemaVersion is the image manifest schema that this image follows
SchemaVersion int `json:"schemaVersion"`
}
// Manifest provides the base accessible fields for working with V2 image
// format in the registry.
type Manifest struct {
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 []ManifestHistory `json:"history"`
}
// 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 (m *Manifest) Sign(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 (m *Manifest) SignWithChain(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
}
// 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:"-"`
}
// Verify verifies the signature of the signed manifest returning the public
// keys used during signing.
func (sm *SignedManifest) Verify() ([]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 (sm *SignedManifest) VerifyChains(ca *x509.CertPool) ([][]*x509.Certificate, error) {
js, err := libtrust.ParsePrettySignature(sm.Raw, "signatures")
if err != nil {
return nil, err
}
return js.VerifyChains(ca)
}
// 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
}
// 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
// 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"`
}
// ManifestHistory stores unstructured v1 compatibility information
type ManifestHistory struct {
// V1Compatibility is the raw v1 compatibility information
V1Compatibility string `json:"v1Compatibility"`
}