diff --git a/api/v2/descriptors.go b/api/v2/descriptors.go index d7d3eed15..2c6fafd02 100644 --- a/api/v2/descriptors.go +++ b/api/v2/descriptors.go @@ -1332,9 +1332,9 @@ var errorDescriptors = []ErrorDescriptor{ { Code: ErrorCodeNameInvalid, Value: "NAME_INVALID", - Message: "manifest name did not match URI", - Description: `During a manifest upload, if the name in the manifest - does not match the uri name, this error will be returned.`, + Message: "invalid repository name", + Description: `Invalid repository name encountered either during + manifest validation or any API operation.`, HTTPStatusCodes: []int{http.StatusBadRequest, http.StatusNotFound}, }, { diff --git a/digest/digest.go b/digest/digest.go index 40f1db159..3c5ae403e 100644 --- a/digest/digest.go +++ b/digest/digest.go @@ -13,6 +13,11 @@ import ( "github.com/docker/docker/pkg/tarsum" ) +const ( + // DigestTarSumV1EmptyTar is the digest for the empty tar file. + DigestTarSumV1EmptyTar = "tarsum.v1+sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855" +) + // Digest allows simple protection of hex formatted digest strings, prefixed // by their algorithm. Strings of type Digest have some guarantee of being in // the correct format and it provides quick access to the components of a diff --git a/digest/digest_test.go b/digest/digest_test.go index 127f7873d..9c1e70e5a 100644 --- a/digest/digest_test.go +++ b/digest/digest_test.go @@ -1,6 +1,10 @@ package digest -import "testing" +import ( + "bytes" + "io" + "testing" +) func TestParseDigest(t *testing.T) { for _, testcase := range []struct { @@ -78,3 +82,25 @@ func TestParseDigest(t *testing.T) { } } } + +// A few test cases used to fix behavior we expect in storage backend. + +func TestFromTarArchiveZeroLength(t *testing.T) { + checkTarsumDigest(t, "zero-length archive", bytes.NewReader([]byte{}), DigestTarSumV1EmptyTar) +} + +func TestFromTarArchiveEmptyTar(t *testing.T) { + // String of 1024 zeros is a valid, empty tar file. + checkTarsumDigest(t, "1024 zero bytes", bytes.NewReader(bytes.Repeat([]byte("\x00"), 1024)), DigestTarSumV1EmptyTar) +} + +func checkTarsumDigest(t *testing.T, msg string, rd io.Reader, expected Digest) { + dgst, err := FromTarArchive(rd) + if err != nil { + t.Fatalf("unexpected error digesting %s: %v", msg, err) + } + + if dgst != expected { + t.Fatalf("unexpected digest for %s: %q != %q", msg, dgst, expected) + } +} diff --git a/registry/api_test.go b/registry/api_test.go index 682549205..5f9e6c386 100644 --- a/registry/api_test.go +++ b/registry/api_test.go @@ -144,7 +144,7 @@ func TestLayerAPI(t *testing.T) { checkResponse(t, "status of deleted upload", resp, http.StatusNotFound) // ----------------------------------------- - // Do layer push with an empty body + // Do layer push with an empty body and different digest uploadURLBase = startPushLayer(t, builder, imageName) resp, err = doPushLayer(t, builder, imageName, layerDigest, uploadURLBase, bytes.NewReader([]byte{})) if err != nil { @@ -152,21 +152,30 @@ func TestLayerAPI(t *testing.T) { } checkResponse(t, "bad layer push", resp, http.StatusBadRequest) - checkBodyHasErrorCodes(t, "bad layer push", resp, v2.ErrorCodeBlobUploadInvalid) + checkBodyHasErrorCodes(t, "bad layer push", resp, v2.ErrorCodeDigestInvalid) // ----------------------------------------- - // Do layer push with an invalid body - - // This is a valid but empty tarfile! - badTar := bytes.Repeat([]byte("\x00"), 1024) - uploadURLBase = startPushLayer(t, builder, imageName) - resp, err = doPushLayer(t, builder, imageName, layerDigest, uploadURLBase, bytes.NewReader(badTar)) + // Do layer push with an empty body and correct digest + zeroDigest, err := digest.FromTarArchive(bytes.NewReader([]byte{})) if err != nil { - t.Fatalf("unexpected error doing bad layer push: %v", err) + t.Fatalf("unexpected error digesting empty buffer: %v", err) } - checkResponse(t, "bad layer push", resp, http.StatusBadRequest) - checkBodyHasErrorCodes(t, "bad layer push", resp, v2.ErrorCodeDigestInvalid) + uploadURLBase = startPushLayer(t, builder, imageName) + pushLayer(t, builder, imageName, zeroDigest, uploadURLBase, bytes.NewReader([]byte{})) + + // ----------------------------------------- + // Do layer push with an empty body and correct digest + + // This is a valid but empty tarfile! + emptyTar := bytes.Repeat([]byte("\x00"), 1024) + emptyDigest, err := digest.FromTarArchive(bytes.NewReader(emptyTar)) + if err != nil { + t.Fatalf("unexpected error digesting empty tar: %v", err) + } + + uploadURLBase = startPushLayer(t, builder, imageName) + pushLayer(t, builder, imageName, emptyDigest, uploadURLBase, bytes.NewReader(emptyTar)) // ------------------------------------------ // Now, actually do successful upload. @@ -517,7 +526,7 @@ func checkBodyHasErrorCodes(t *testing.T, msg string, resp *http.Response, error for _, err := range errs.Errors { if _, ok := expected[err.Code]; !ok { - t.Fatalf("unexpected error code %v encountered: %s ", err.Code, string(p)) + t.Fatalf("unexpected error code %v encountered during %s: %s ", err.Code, msg, string(p)) } counts[err.Code]++ } @@ -525,7 +534,7 @@ func checkBodyHasErrorCodes(t *testing.T, msg string, resp *http.Response, error // Ensure that counts of expected errors were all non-zero for code := range expected { if counts[code] == 0 { - t.Fatalf("expected error code %v not encounterd: %s", code, string(p)) + t.Fatalf("expected error code %v not encounterd during %s: %s", code, msg, string(p)) } } diff --git a/registry/layerupload.go b/registry/layerupload.go index e9585b0ec..cfce98f3a 100644 --- a/registry/layerupload.go +++ b/registry/layerupload.go @@ -198,13 +198,6 @@ func (luh *layerUploadHandler) PutLayerUploadComplete(w http.ResponseWriter, r * layer, err := luh.Upload.Finish(dgst) if err != nil { switch err := err.(type) { - case storage.ErrLayerUploadUnavailable: - w.WriteHeader(http.StatusBadRequest) - // TODO(stevvooe): Arguably, we may want to add an error code to - // cover this condition. It is not always a client error but it - // may be. For now, we effectively throw out the upload and have - // them start over. - luh.Errors.Push(v2.ErrorCodeBlobUploadInvalid, err.Err) case storage.ErrLayerInvalidDigest: w.WriteHeader(http.StatusBadRequest) luh.Errors.Push(v2.ErrorCodeDigestInvalid, err) diff --git a/storage/filereader.go b/storage/filereader.go index 9a6eb2b37..9bc09afef 100644 --- a/storage/filereader.go +++ b/storage/filereader.go @@ -2,14 +2,23 @@ package storage import ( "bufio" + "bytes" "fmt" "io" + "io/ioutil" "os" "time" "github.com/docker/distribution/storagedriver" ) +// TODO(stevvooe): Set an optimal buffer size here. We'll have to +// understand the latency characteristics of the underlying network to +// set this correctly, so we may want to leave it to the driver. For +// out of process drivers, we'll have to optimize this buffer size for +// local communication. +const fileReaderBufferSize = 4 << 20 + // remoteFileReader provides a read seeker interface to files stored in // storagedriver. Used to implement part of layer interface and will be used // to implement read side of LayerUpload. @@ -28,24 +37,40 @@ type fileReader struct { err error // terminal error, if set, reader is closed } +// newFileReader initializes a file reader for the remote file. The read takes +// on the offset and size at the time the reader is created. If the underlying +// file changes, one must create a new fileReader. func newFileReader(driver storagedriver.StorageDriver, path string) (*fileReader, error) { + rd := &fileReader{ + driver: driver, + path: path, + } + // Grab the size of the layer file, ensuring existence. - fi, err := driver.Stat(path) + if fi, err := driver.Stat(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. If the caller needs to know + // whether or not the file exists, they should issue a stat call + // on the path. There is still no guarantee, since the file may be + // gone by the time the reader is created. The only correct + // behavior is to return a reader that immediately returns EOF. + default: + // Any other error we want propagated up the stack. + return nil, err + } + } else { + if fi.IsDir() { + return nil, fmt.Errorf("cannot read a directory") + } - if err != nil { - return nil, err + // Fill in file information + rd.size = fi.Size() + rd.modtime = fi.ModTime() } - if fi.IsDir() { - return nil, fmt.Errorf("cannot read a directory") - } - - return &fileReader{ - driver: driver, - path: path, - size: fi.Size(), - modtime: fi.ModTime(), - }, nil + return rd, nil } func (fr *fileReader) Read(p []byte) (n int, err error) { @@ -88,8 +113,6 @@ func (fr *fileReader) Seek(offset int64, whence int) (int64, error) { if newOffset < 0 { err = fmt.Errorf("cannot seek to negative position") - } else if newOffset > fr.size { - err = fmt.Errorf("cannot seek passed end of file") } else { if fr.offset != newOffset { fr.reset() @@ -134,9 +157,17 @@ func (fr *fileReader) reader() (io.Reader, error) { // If we don't have a reader, open one up. rc, err := fr.driver.ReadStream(fr.path, fr.offset) - if err != nil { - return nil, err + switch err := err.(type) { + case storagedriver.PathNotFoundError: + // NOTE(stevvooe): If the path is not found, we simply return a + // reader that returns io.EOF. However, we do not set fr.rc, + // allowing future attempts at getting a reader to possibly + // succeed if the file turns up later. + return ioutil.NopCloser(bytes.NewReader([]byte{})), nil + default: + return nil, err + } } fr.rc = rc @@ -147,7 +178,7 @@ func (fr *fileReader) reader() (io.Reader, error) { // set this correctly, so we may want to leave it to the driver. For // out of process drivers, we'll have to optimize this buffer size for // local communication. - fr.brd = bufio.NewReader(fr.rc) + fr.brd = bufio.NewReaderSize(fr.rc, fileReaderBufferSize) } else { fr.brd.Reset(fr.rc) } diff --git a/storage/filereader_test.go b/storage/filereader_test.go index 7cf5633d3..53dd6c9a5 100644 --- a/storage/filereader_test.go +++ b/storage/filereader_test.go @@ -124,7 +124,7 @@ func TestFileReaderSeek(t *testing.T) { t.Fatalf("expected to seek to end: %v != %v", end, len(content)) } - // 4. Seek past end and before start, ensure error. + // 4. Seek before start, ensure error. // seek before start before, err := fr.Seek(-1, os.SEEK_SET) @@ -132,9 +132,44 @@ func TestFileReaderSeek(t *testing.T) { t.Fatalf("error expected, returned offset=%v", before) } - after, err := fr.Seek(int64(len(content)+1), os.SEEK_END) - if err == nil { - t.Fatalf("error expected, returned offset=%v", after) + // 5. Seek after end, + after, err := fr.Seek(1, os.SEEK_END) + if err != nil { + t.Fatalf("unexpected error expected, returned offset=%v", after) + } + + p := make([]byte, 16) + n, err := fr.Read(p) + + if n != 0 { + t.Fatalf("bytes reads %d != %d", n, 0) + } + + if err != io.EOF { + t.Fatalf("expected io.EOF, got %v", err) + } +} + +// TestFileReaderNonExistentFile ensures the reader behaves as expected with a +// missing or zero-length remote file. While the file may not exist, the +// reader should not error out on creation and should return 0-bytes from the +// read method, with an io.EOF error. +func TestFileReaderNonExistentFile(t *testing.T) { + driver := inmemory.New() + fr, err := newFileReader(driver, "/doesnotexist") + if err != nil { + t.Fatalf("unexpected error initializing reader: %v", err) + } + + var buf [1024]byte + + n, err := fr.Read(buf[:]) + if n != 0 { + t.Fatalf("non-zero byte read reported: %d != 0", n) + } + + if err != io.EOF { + t.Fatalf("read on missing file should return io.EOF, got %v", err) } } diff --git a/storage/filewriter.go b/storage/filewriter.go index cfa7c93de..5037f1608 100644 --- a/storage/filewriter.go +++ b/storage/filewriter.go @@ -99,9 +99,6 @@ func (fw *fileWriter) Seek(offset int64, whence int) (int64, error) { if newOffset < 0 { err = fmt.Errorf("cannot seek to negative position") - } else if newOffset > fw.size { - fw.offset = newOffset - fw.size = newOffset } else { // No problems, set the offset. fw.offset = newOffset diff --git a/storage/layer.go b/storage/layer.go index b7d84a984..627a3b5f7 100644 --- a/storage/layer.go +++ b/storage/layer.go @@ -80,28 +80,10 @@ func (err ErrUnknownLayer) Error() string { // ErrLayerInvalidDigest returned when tarsum check fails. type ErrLayerInvalidDigest struct { Digest digest.Digest + Reason error } func (err ErrLayerInvalidDigest) Error() string { - return fmt.Sprintf("invalid digest for referenced layer: %v", err.Digest) -} - -// ErrLayerInvalidSize returned when length check fails. -type ErrLayerInvalidSize struct { - Size int64 -} - -func (err ErrLayerInvalidSize) Error() string { - return fmt.Sprintf("invalid layer size: %d", err.Size) -} - -// ErrLayerUploadUnavailable signals missing upload data, either when no data -// has been received or when the backend reports the data as missing. This is -// different from ErrLayerUploadUnknown. -type ErrLayerUploadUnavailable struct { - Err error -} - -func (err ErrLayerUploadUnavailable) Error() string { - return fmt.Sprintf("layer upload unavialable: %v", err) + return fmt.Sprintf("invalid digest for referenced layer: %v, %v", + err.Digest, err.Reason) } diff --git a/storage/layer_test.go b/storage/layer_test.go index 7da64190a..2a551694e 100644 --- a/storage/layer_test.go +++ b/storage/layer_test.go @@ -235,6 +235,40 @@ func TestSimpleLayerRead(t *testing.T) { } } +// TestLayerUploadZeroLength uploads zero-length +func TestLayerUploadZeroLength(t *testing.T) { + imageName := "foo/bar" + driver := inmemory.New() + registry := NewRegistryWithDriver(driver) + ls := registry.Repository(imageName).Layers() + + upload, err := ls.Upload() + if err != nil { + t.Fatalf("unexpected error starting upload: %v", err) + } + + io.Copy(upload, bytes.NewReader([]byte{})) + + dgst, err := digest.FromTarArchive(bytes.NewReader([]byte{})) + if err != nil { + t.Fatalf("error getting zero digest: %v", err) + } + + if dgst != digest.DigestTarSumV1EmptyTar { + // sanity check on zero digest + t.Fatalf("digest not as expected: %v != %v", dgst, digest.DigestTarSumV1EmptyTar) + } + + layer, err := upload.Finish(dgst) + if err != nil { + t.Fatalf("unexpected error finishing upload: %v", err) + } + + if layer.Digest() != dgst { + t.Fatalf("unexpected digest: %v != %v", layer.Digest(), dgst) + } +} + // writeRandomLayer creates a random layer under name and tarSum using driver // and pathMapper. An io.ReadSeeker with the data is returned, along with the // sha256 hex digest. diff --git a/storage/layerupload.go b/storage/layerupload.go index dbd9140e2..0c69e30da 100644 --- a/storage/layerupload.go +++ b/storage/layerupload.go @@ -1,6 +1,7 @@ package storage import ( + "fmt" "io" "path" "time" @@ -89,7 +90,10 @@ func (luc *layerUploadController) validateLayer(dgst digest.Digest) (digest.Dige case tarsum.Version1: default: // version 0 and dev, for now. - return "", ErrLayerTarSumVersionUnsupported + return "", ErrLayerInvalidDigest{ + Digest: dgst, + Reason: ErrLayerTarSumVersionUnsupported, + } } digestVerifier := digest.NewDigestVerifier(dgst) @@ -102,22 +106,7 @@ func (luc *layerUploadController) validateLayer(dgst digest.Digest) (digest.Dige // Read the file from the backend driver and validate it. fr, err := newFileReader(luc.fileWriter.driver, luc.path) if err != nil { - switch err := err.(type) { - case storagedriver.PathNotFoundError: - // NOTE(stevvooe): Path not found can mean several things by we - // should report the upload is not available. This can happen if - // the following happens: - // - // 1. If not data was received for the upload instance. - // 2. Backend storage driver has not convereged after receiving latest data. - // - // This *does not* mean that the upload does not exist, since we - // can't even get a LayerUpload object without having the - // directory exist. - return "", ErrLayerUploadUnavailable{Err: err} - default: - return "", err - } + return "", err } tr := io.TeeReader(fr, digestVerifier) @@ -132,7 +121,10 @@ func (luc *layerUploadController) validateLayer(dgst digest.Digest) (digest.Dige } if !digestVerifier.Verified() { - return "", ErrLayerInvalidDigest{Digest: dgst} + return "", ErrLayerInvalidDigest{ + Digest: dgst, + Reason: fmt.Errorf("content does not match digest"), + } } return canonical, nil @@ -151,7 +143,7 @@ func (luc *layerUploadController) moveLayer(dgst digest.Digest) error { } // Check for existence - if _, err := luc.layerStore.repository.registry.driver.Stat(blobPath); err != nil { + if _, err := luc.driver.Stat(blobPath); err != nil { switch err := err.(type) { case storagedriver.PathNotFoundError: break // ensure that it doesn't exist. @@ -166,6 +158,31 @@ func (luc *layerUploadController) moveLayer(dgst digest.Digest) error { return nil } + // If no data was received, we may not actually have a file on disk. Check + // the size here and write a zero-length file to blobPath if this is the + // case. For the most part, this should only ever happen with zero-length + // tars. + if _, err := luc.driver.Stat(luc.path); err != nil { + switch err := err.(type) { + case storagedriver.PathNotFoundError: + // HACK(stevvooe): This is slightly dangerous: if we verify above, + // get a hash, then the underlying file is deleted, we risk moving + // a zero-length blob into a nonzero-length blob location. To + // prevent this horrid thing, we employ the hack of only allowing + // to this happen for the zero tarsum. + if dgst == digest.DigestTarSumV1EmptyTar { + return luc.driver.PutContent(blobPath, []byte{}) + } + + // We let this fail during the move below. + logrus. + WithField("upload.uuid", luc.UUID()). + WithField("digest", dgst).Warnf("attempted to move zero-length content with non-zero digest") + default: + return err // unrelated error + } + } + return luc.driver.Move(luc.path, blobPath) } diff --git a/storage/revisionstore.go b/storage/revisionstore.go index 97518df19..a88ca8c77 100644 --- a/storage/revisionstore.go +++ b/storage/revisionstore.go @@ -57,8 +57,6 @@ func (rs *revisionStore) get(revision digest.Digest) (*manifest.SignedManifest, return nil, err } - logrus.Infof("retrieved signatures: %v", string(signatures[0])) - jsig, err := libtrust.NewJSONSignature(content, signatures...) if err != nil { return nil, err