示例#1
0
// UpdateSnapshotHashes updates the snapshot to reflect the latest hash changes, to
// ensure that failure isn't because the snapshot has the wrong hash.
func (m *MetadataSwizzler) UpdateSnapshotHashes(roles ...string) error {
	var (
		metaBytes      []byte
		snapshotSigned *data.Signed
		err            error
	)
	if metaBytes, err = m.MetadataCache.GetSized(data.CanonicalSnapshotRole, store.NoSizeLimit); err != nil {
		return err
	}

	snapshot := data.SignedSnapshot{}
	if err = json.Unmarshal(metaBytes, &snapshot); err != nil {
		return err
	}

	// just rebuild everything if roles is not specified
	if len(roles) == 0 {
		roles = m.Roles
	}

	for _, role := range roles {
		if role != data.CanonicalSnapshotRole && role != data.CanonicalTimestampRole {
			if metaBytes, err = m.MetadataCache.GetSized(role, store.NoSizeLimit); err != nil {
				return err
			}

			meta, err := data.NewFileMeta(bytes.NewReader(metaBytes), data.NotaryDefaultHashes...)
			if err != nil {
				return err
			}

			snapshot.Signed.Meta[role] = meta
		}
	}

	if snapshotSigned, err = snapshot.ToSigned(); err != nil {
		return err
	}
	pubKeys, err := getPubKeys(m.CryptoService, snapshotSigned, data.CanonicalSnapshotRole)
	if err == nil {
		metaBytes, err = serializeMetadata(m.CryptoService, snapshotSigned, data.CanonicalSnapshotRole, pubKeys...)
	}

	if err != nil {
		return err
	}
	return m.MetadataCache.Set(data.CanonicalSnapshotRole, metaBytes)
}
示例#2
0
// createSnapshot uses an existing snapshot to create a new one.
// Important things to be aware of:
//   - It requires that a snapshot already exists. We create snapshots
//     on upload so there should always be an existing snapshot if this
//     gets called.
//   - It doesn't update what roles are present in the snapshot, as those
//     were validated during upload.
func createSnapshot(gun string, sn *data.SignedSnapshot, store storage.MetaStore, cryptoService signed.CryptoService) (*data.Signed, int, error) {
	algorithm, public, err := store.GetKey(gun, data.CanonicalSnapshotRole)
	if err != nil {
		// owner of gun must have generated a snapshot key otherwise
		// we won't proceed with generating everything.
		return nil, 0, err
	}
	key := data.NewPublicKey(algorithm, public)

	// update version and expiry
	sn.Signed.Version = sn.Signed.Version + 1
	sn.Signed.Expires = data.DefaultExpires(data.CanonicalSnapshotRole)

	out, err := sn.ToSigned()
	if err != nil {
		return nil, 0, err
	}
	err = signed.Sign(cryptoService, out, key)
	if err != nil {
		return nil, 0, err
	}
	return out, sn.Signed.Version, nil
}