docker/graph/manifest.go

107 строки
3.2 KiB
Go

package graph
import (
"encoding/json"
"fmt"
"github.com/Sirupsen/logrus"
"github.com/docker/distribution/digest"
"github.com/docker/docker/registry"
"github.com/docker/docker/trust"
"github.com/docker/docker/utils"
"github.com/docker/libtrust"
)
// loadManifest loads a manifest from a byte array and verifies its content.
// The signature must be verified or an error is returned. If the manifest
// contains no signatures by a trusted key for the name in the manifest, the
// image is not considered verified. The parsed manifest object and a boolean
// for whether the manifest is verified is returned.
func (s *TagStore) loadManifest(manifestBytes []byte, dgst, ref string) (*registry.ManifestData, bool, error) {
sig, err := libtrust.ParsePrettySignature(manifestBytes, "signatures")
if err != nil {
return nil, false, fmt.Errorf("error parsing payload: %s", err)
}
keys, err := sig.Verify()
if err != nil {
return nil, false, fmt.Errorf("error verifying payload: %s", err)
}
payload, err := sig.Payload()
if err != nil {
return nil, false, fmt.Errorf("error retrieving payload: %s", err)
}
var manifestDigest digest.Digest
if dgst != "" {
manifestDigest, err = digest.ParseDigest(dgst)
if err != nil {
return nil, false, fmt.Errorf("invalid manifest digest from registry: %s", err)
}
dgstVerifier, err := digest.NewDigestVerifier(manifestDigest)
if err != nil {
return nil, false, fmt.Errorf("unable to verify manifest digest from registry: %s", err)
}
dgstVerifier.Write(payload)
if !dgstVerifier.Verified() {
computedDigest, _ := digest.FromBytes(payload)
return nil, false, fmt.Errorf("unable to verify manifest digest: registry has %q, computed %q", manifestDigest, computedDigest)
}
}
if utils.DigestReference(ref) && ref != manifestDigest.String() {
return nil, false, fmt.Errorf("mismatching image manifest digest: got %q, expected %q", manifestDigest, ref)
}
var manifest registry.ManifestData
if err := json.Unmarshal(payload, &manifest); err != nil {
return nil, false, fmt.Errorf("error unmarshalling manifest: %s", err)
}
if manifest.SchemaVersion != 1 {
return nil, false, fmt.Errorf("unsupported schema version: %d", manifest.SchemaVersion)
}
var verified bool
for _, key := range keys {
namespace := manifest.Name
if namespace[0] != '/' {
namespace = "/" + namespace
}
b, err := key.MarshalJSON()
if err != nil {
return nil, false, fmt.Errorf("error marshalling public key: %s", err)
}
// Check key has read/write permission (0x03)
v, err := s.trustService.CheckKey(namespace, b, 0x03)
if err != nil {
vErr, ok := err.(trust.NotVerifiedError)
if !ok {
return nil, false, fmt.Errorf("error running key check: %s", err)
}
logrus.Debugf("Key check result: %v", vErr)
}
verified = v
if verified {
logrus.Debug("Key check result: verified")
}
}
return &manifest, verified, nil
}
func checkValidManifest(manifest *registry.ManifestData) error {
if len(manifest.FSLayers) != len(manifest.History) {
return fmt.Errorf("length of history not equal to number of layers")
}
if len(manifest.FSLayers) == 0 {
return fmt.Errorf("no FSLayers in manifest")
}
return nil
}