예제 #1
0
func (p *v2Puller) download(di *downloadInfo) {
	logrus.Debugf("pulling blob %q to %s", di.digest, di.img.id)

	blobs := p.repo.Blobs(context.Background())

	desc, err := blobs.Stat(context.Background(), di.digest)
	if err != nil {
		logrus.Debugf("Error statting layer: %v", err)
		di.err <- err
		return
	}
	di.size = desc.Size

	layerDownload, err := blobs.Open(context.Background(), di.digest)
	if err != nil {
		logrus.Debugf("Error fetching layer: %v", err)
		di.err <- err
		return
	}
	defer layerDownload.Close()

	verifier, err := digest.NewDigestVerifier(di.digest)
	if err != nil {
		di.err <- err
		return
	}

	reader := progressreader.New(progressreader.Config{
		In:        ioutil.NopCloser(io.TeeReader(layerDownload, verifier)),
		Out:       di.broadcaster,
		Formatter: p.sf,
		Size:      di.size,
		NewLines:  false,
		ID:        stringid.TruncateID(di.img.id),
		Action:    "Downloading",
	})
	io.Copy(di.tmpFile, reader)

	di.broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(di.img.id), "Verifying Checksum", nil))

	if !verifier.Verified() {
		err = fmt.Errorf("filesystem layer verification failed for digest %s", di.digest)
		logrus.Error(err)
		di.err <- err
		return
	}

	di.broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(di.img.id), "Download complete", nil))

	logrus.Debugf("Downloaded %s to tempfile %s", di.img.id, di.tmpFile.Name())
	di.layer = layerDownload

	di.err <- nil
}
예제 #2
0
파일: session_v2.go 프로젝트: devick/flynn
// Finally Push the (signed) manifest of the blobs we've just pushed
func (r *Session) PutV2ImageManifest(ep *Endpoint, imageName, tagName string, signedManifest, rawManifest []byte, auth *RequestAuthorization) (digest.Digest, error) {
	routeURL, err := getV2Builder(ep).BuildManifestURL(imageName, tagName)
	if err != nil {
		return "", err
	}

	method := "PUT"
	log.Debugf("[registry] Calling %q %s", method, routeURL)
	req, err := r.reqFactory.NewRequest(method, routeURL, bytes.NewReader(signedManifest))
	if err != nil {
		return "", err
	}
	if err := auth.Authorize(req); err != nil {
		return "", err
	}
	res, _, err := r.doRequest(req)
	if err != nil {
		return "", err
	}
	defer res.Body.Close()

	// All 2xx and 3xx responses can be accepted for a put.
	if res.StatusCode >= 400 {
		if res.StatusCode == 401 {
			return "", errLoginRequired
		}
		errBody, err := ioutil.ReadAll(res.Body)
		if err != nil {
			return "", err
		}
		log.Debugf("Unexpected response from server: %q %#v", errBody, res.Header)
		return "", utils.NewHTTPRequestError(fmt.Sprintf("Server error: %d trying to push %s:%s manifest", res.StatusCode, imageName, tagName), res)
	}

	hdrDigest, err := digest.ParseDigest(res.Header.Get(DockerDigestHeader))
	if err != nil {
		return "", fmt.Errorf("invalid manifest digest from registry: %s", err)
	}

	dgstVerifier, err := digest.NewDigestVerifier(hdrDigest)
	if err != nil {
		return "", fmt.Errorf("invalid manifest digest from registry: %s", err)
	}

	dgstVerifier.Write(rawManifest)

	if !dgstVerifier.Verified() {
		computedDigest, _ := digest.FromBytes(rawManifest)
		return "", fmt.Errorf("unable to verify manifest digest: registry has %q, computed %q", hdrDigest, computedDigest)
	}

	return hdrDigest, nil
}
예제 #3
0
func verifyManifest(signedManifest *manifest.SignedManifest, tag string) (m *manifest.Manifest, err error) {
	// If pull by digest, then verify the manifest digest. NOTE: It is
	// important to do this first, before any other content validation. If the
	// digest cannot be verified, don't even bother with those other things.
	if manifestDigest, err := digest.ParseDigest(tag); err == nil {
		verifier, err := digest.NewDigestVerifier(manifestDigest)
		if err != nil {
			return nil, err
		}
		payload, err := signedManifest.Payload()
		if err != nil {
			// If this failed, the signatures section was corrupted
			// or missing. Treat the entire manifest as the payload.
			payload = signedManifest.Raw
		}
		if _, err := verifier.Write(payload); err != nil {
			return nil, err
		}
		if !verifier.Verified() {
			err := fmt.Errorf("image verification failed for digest %s", manifestDigest)
			logrus.Error(err)
			return nil, err
		}

		var verifiedManifest manifest.Manifest
		if err = json.Unmarshal(payload, &verifiedManifest); err != nil {
			return nil, err
		}
		m = &verifiedManifest
	} else {
		m = &signedManifest.Manifest
	}

	if m.SchemaVersion != 1 {
		return nil, fmt.Errorf("unsupported schema version %d for tag %q", m.SchemaVersion, tag)
	}
	if len(m.FSLayers) != len(m.History) {
		return nil, fmt.Errorf("length of history not equal to number of layers for tag %q", tag)
	}
	if len(m.FSLayers) == 0 {
		return nil, fmt.Errorf("no FSLayers in manifest for tag %q", tag)
	}
	return m, nil
}
예제 #4
0
파일: manifest.go 프로젝트: devick/flynn
// 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(eng *engine.Engine, 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 {
		job := eng.Job("trust_key_check")
		b, err := key.MarshalJSON()
		if err != nil {
			return nil, false, fmt.Errorf("error marshalling public key: %s", err)
		}
		namespace := manifest.Name
		if namespace[0] != '/' {
			namespace = "/" + namespace
		}
		stdoutBuffer := bytes.NewBuffer(nil)

		job.Args = append(job.Args, namespace)
		job.Setenv("PublicKey", string(b))
		// Check key has read/write permission (0x03)
		job.SetenvInt("Permission", 0x03)
		job.Stdout.Add(stdoutBuffer)
		if err = job.Run(); err != nil {
			return nil, false, fmt.Errorf("error running key check: %s", err)
		}
		result := engine.Tail(stdoutBuffer, 1)
		log.Debugf("Key check result: %q", result)
		if result == "verified" {
			verified = true
		}
	}

	return &manifest, verified, nil
}
예제 #5
0
// validateBlob checks the data against the digest, returning an error if it
// does not match. The canonical descriptor is returned.
func (bw *blobWriter) validateBlob(ctx context.Context, desc distribution.Descriptor) (distribution.Descriptor, error) {
	var (
		verified, fullHash bool
		canonical          digest.Digest
	)

	if desc.Digest == "" {
		// if no descriptors are provided, we have nothing to validate
		// against. We don't really want to support this for the registry.
		return distribution.Descriptor{}, distribution.ErrBlobInvalidDigest{
			Reason: fmt.Errorf("cannot validate against empty digest"),
		}
	}

	// Stat the on disk file
	if fi, err := bw.bufferedFileWriter.driver.Stat(ctx, bw.path); err != nil {
		switch err := err.(type) {
		case storagedriver.PathNotFoundError:
			// NOTE(stevvooe): We really don't care if the file is
			// not actually present for the reader. We now assume
			// that the desc length is zero.
			desc.Size = 0
		default:
			// Any other error we want propagated up the stack.
			return distribution.Descriptor{}, err
		}
	} else {
		if fi.IsDir() {
			return distribution.Descriptor{}, fmt.Errorf("unexpected directory at upload location %q", bw.path)
		}

		bw.size = fi.Size()
	}

	if desc.Size > 0 {
		if desc.Size != bw.size {
			return distribution.Descriptor{}, distribution.ErrBlobInvalidLength
		}
	} else {
		// if provided 0 or negative length, we can assume caller doesn't know or
		// care about length.
		desc.Size = bw.size
	}

	// TODO(stevvooe): This section is very meandering. Need to be broken down
	// to be a lot more clear.

	if err := bw.resumeDigestAt(ctx, bw.size); err == nil {
		canonical = bw.digester.Digest()

		if canonical.Algorithm() == desc.Digest.Algorithm() {
			// Common case: client and server prefer the same canonical digest
			// algorithm - currently SHA256.
			verified = desc.Digest == canonical
		} else {
			// The client wants to use a different digest algorithm. They'll just
			// have to be patient and wait for us to download and re-hash the
			// uploaded content using that digest algorithm.
			fullHash = true
		}
	} else if err == errResumableDigestNotAvailable {
		// Not using resumable digests, so we need to hash the entire layer.
		fullHash = true
	} else {
		return distribution.Descriptor{}, err
	}

	if fullHash {
		// a fantastic optimization: if the the written data and the size are
		// the same, we don't need to read the data from the backend. This is
		// because we've written the entire file in the lifecycle of the
		// current instance.
		if bw.written == bw.size && digest.Canonical == desc.Digest.Algorithm() {
			canonical = bw.digester.Digest()
			verified = desc.Digest == canonical
		}

		// If the check based on size fails, we fall back to the slowest of
		// paths. We may be able to make the size-based check a stronger
		// guarantee, so this may be defensive.
		if !verified {
			digester := digest.Canonical.New()

			digestVerifier, err := digest.NewDigestVerifier(desc.Digest)
			if err != nil {
				return distribution.Descriptor{}, err
			}

			// Read the file from the backend driver and validate it.
			fr, err := newFileReader(ctx, bw.bufferedFileWriter.driver, bw.path, desc.Size)
			if err != nil {
				return distribution.Descriptor{}, err
			}

			tr := io.TeeReader(fr, digester.Hash())

			if _, err := io.Copy(digestVerifier, tr); err != nil {
				return distribution.Descriptor{}, err
			}

			canonical = digester.Digest()
			verified = digestVerifier.Verified()
		}
	}

	if !verified {
		context.GetLoggerWithFields(ctx,
			map[string]interface{}{
				"canonical": canonical,
				"provided":  desc.Digest,
			}, "canonical", "provided").
			Errorf("canonical digest does match provided digest")
		return distribution.Descriptor{}, distribution.ErrBlobInvalidDigest{
			Digest: desc.Digest,
			Reason: fmt.Errorf("content does not match digest"),
		}
	}

	// update desc with canonical hash
	desc.Digest = canonical

	if desc.MediaType == "" {
		desc.MediaType = "application/octet-stream"
	}

	return desc, nil
}
예제 #6
0
파일: pull.go 프로젝트: devick/flynn
func (s *TagStore) pullV2Tag(eng *engine.Engine, r *registry.Session, out io.Writer, endpoint *registry.Endpoint, repoInfo *registry.RepositoryInfo, tag string, sf *utils.StreamFormatter, parallel bool, auth *registry.RequestAuthorization) (bool, error) {
	log.Debugf("Pulling tag from V2 registry: %q", tag)

	manifestBytes, manifestDigest, err := r.GetV2ImageManifest(endpoint, repoInfo.RemoteName, tag, auth)
	if err != nil {
		return false, err
	}

	// loadManifest ensures that the manifest payload has the expected digest
	// if the tag is a digest reference.
	manifest, verified, err := s.loadManifest(eng, manifestBytes, manifestDigest, tag)
	if err != nil {
		return false, fmt.Errorf("error verifying manifest: %s", err)
	}

	if err := checkValidManifest(manifest); err != nil {
		return false, err
	}

	if verified {
		log.Printf("Image manifest for %s has been verified", utils.ImageReference(repoInfo.CanonicalName, tag))
	}
	out.Write(sf.FormatStatus(tag, "Pulling from %s", repoInfo.CanonicalName))

	downloads := make([]downloadInfo, len(manifest.FSLayers))

	for i := len(manifest.FSLayers) - 1; i >= 0; i-- {
		var (
			sumStr  = manifest.FSLayers[i].BlobSum
			imgJSON = []byte(manifest.History[i].V1Compatibility)
		)

		img, err := image.NewImgJSON(imgJSON)
		if err != nil {
			return false, fmt.Errorf("failed to parse json: %s", err)
		}
		downloads[i].img = img

		// Check if exists
		if s.graph.Exists(img.ID) {
			log.Debugf("Image already exists: %s", img.ID)
			continue
		}

		dgst, err := digest.ParseDigest(sumStr)
		if err != nil {
			return false, err
		}
		downloads[i].digest = dgst

		out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Pulling fs layer", nil))

		downloadFunc := func(di *downloadInfo) error {
			log.Debugf("pulling blob %q to V1 img %s", sumStr, img.ID)

			if c, err := s.poolAdd("pull", "img:"+img.ID); err != nil {
				if c != nil {
					out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Layer already being pulled by another client. Waiting.", nil))
					<-c
					out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Download complete", nil))
				} else {
					log.Debugf("Image (id: %s) pull is already running, skipping: %v", img.ID, err)
				}
			} else {
				defer s.poolRemove("pull", "img:"+img.ID)
				tmpFile, err := ioutil.TempFile("", "GetV2ImageBlob")
				if err != nil {
					return err
				}

				r, l, err := r.GetV2ImageBlobReader(endpoint, repoInfo.RemoteName, di.digest.Algorithm(), di.digest.Hex(), auth)
				if err != nil {
					return err
				}
				defer r.Close()

				verifier, err := digest.NewDigestVerifier(di.digest)
				if err != nil {
					return err
				}

				if _, err := io.Copy(tmpFile, progressreader.New(progressreader.Config{
					In:        ioutil.NopCloser(io.TeeReader(r, verifier)),
					Out:       out,
					Formatter: sf,
					Size:      int(l),
					NewLines:  false,
					ID:        stringid.TruncateID(img.ID),
					Action:    "Downloading",
				})); err != nil {
					return fmt.Errorf("unable to copy v2 image blob data: %s", err)
				}

				out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Verifying Checksum", nil))

				if !verifier.Verified() {
					log.Infof("Image verification failed: checksum mismatch for %q", di.digest.String())
					verified = false
				}

				out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Download complete", nil))

				log.Debugf("Downloaded %s to tempfile %s", img.ID, tmpFile.Name())
				di.tmpFile = tmpFile
				di.length = l
				di.downloaded = true
			}
			di.imgJSON = imgJSON

			return nil
		}

		if parallel {
			downloads[i].err = make(chan error)
			go func(di *downloadInfo) {
				di.err <- downloadFunc(di)
			}(&downloads[i])
		} else {
			err := downloadFunc(&downloads[i])
			if err != nil {
				return false, err
			}
		}
	}

	var tagUpdated bool
	for i := len(downloads) - 1; i >= 0; i-- {
		d := &downloads[i]
		if d.err != nil {
			err := <-d.err
			if err != nil {
				return false, err
			}
		}
		if d.downloaded {
			// if tmpFile is empty assume download and extracted elsewhere
			defer os.Remove(d.tmpFile.Name())
			defer d.tmpFile.Close()
			d.tmpFile.Seek(0, 0)
			if d.tmpFile != nil {
				err = s.graph.Register(d.img,
					progressreader.New(progressreader.Config{
						In:        d.tmpFile,
						Out:       out,
						Formatter: sf,
						Size:      int(d.length),
						ID:        stringid.TruncateID(d.img.ID),
						Action:    "Extracting",
					}))
				if err != nil {
					return false, err
				}

				// FIXME: Pool release here for parallel tag pull (ensures any downloads block until fully extracted)
			}
			out.Write(sf.FormatProgress(stringid.TruncateID(d.img.ID), "Pull complete", nil))
			tagUpdated = true
		} else {
			out.Write(sf.FormatProgress(stringid.TruncateID(d.img.ID), "Already exists", nil))
		}

	}

	// Check for new tag if no layers downloaded
	if !tagUpdated {
		repo, err := s.Get(repoInfo.LocalName)
		if err != nil {
			return false, err
		}
		if repo != nil {
			if _, exists := repo[tag]; !exists {
				tagUpdated = true
			}
		}
	}

	if verified && tagUpdated {
		out.Write(sf.FormatStatus(utils.ImageReference(repoInfo.CanonicalName, tag), "The image you are pulling has been verified. Important: image verification is a tech preview feature and should not be relied on to provide security."))
	}

	if manifestDigest != "" {
		out.Write(sf.FormatStatus("", "Digest: %s", manifestDigest))
	}

	if utils.DigestReference(tag) {
		if err = s.SetDigest(repoInfo.LocalName, tag, downloads[0].img.ID); err != nil {
			return false, err
		}
	} else {
		// only set the repository/tag -> image ID mapping when pulling by tag (i.e. not by digest)
		if err = s.Set(repoInfo.LocalName, tag, downloads[0].img.ID, true); err != nil {
			return false, err
		}
	}

	return tagUpdated, nil
}