Added to vendor

vendor/github.com/containers/image/oci/archive/oci_dest.go

@@ -0,0 +1,131 @@
+package archive
+
+import (
+	"io"
+	"os"
+
+	"github.com/containers/image/types"
+	"github.com/containers/storage/pkg/archive"
+	"github.com/pkg/errors"
+)
+
+type ociArchiveImageDestination struct {
+	ref          ociArchiveReference
+	unpackedDest types.ImageDestination
+	tempDirRef   tempDirOCIRef
+}
+
+// newImageDestination returns an ImageDestination for writing to an existing directory.
+func newImageDestination(ctx *types.SystemContext, ref ociArchiveReference) (types.ImageDestination, error) {
+	tempDirRef, err := createOCIRef(ref.image)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error creating oci reference")
+	}
+	unpackedDest, err := tempDirRef.ociRefExtracted.NewImageDestination(ctx)
+	if err != nil {
+		if err := tempDirRef.deleteTempDir(); err != nil {
+			return nil, errors.Wrapf(err, "error deleting temp directory", tempDirRef.tempDirectory)
+		}
+		return nil, err
+	}
+	return &ociArchiveImageDestination{ref: ref,
+		unpackedDest: unpackedDest,
+		tempDirRef:   tempDirRef}, nil
+}
+
+// Reference returns the reference used to set up this destination.
+func (d *ociArchiveImageDestination) Reference() types.ImageReference {
+	return d.ref
+}
+
+// Close removes resources associated with an initialized ImageDestination, if any
+// Close deletes the temp directory of the oci-archive image
+func (d *ociArchiveImageDestination) Close() error {
+	defer d.tempDirRef.deleteTempDir()
+	return d.unpackedDest.Close()
+}
+
+func (d *ociArchiveImageDestination) SupportedManifestMIMETypes() []string {
+	return d.unpackedDest.SupportedManifestMIMETypes()
+}
+
+// SupportsSignatures returns an error (to be displayed to the user) if the destination certainly can't store signatures
+func (d *ociArchiveImageDestination) SupportsSignatures() error {
+	return d.unpackedDest.SupportsSignatures()
+}
+
+// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination
+func (d *ociArchiveImageDestination) ShouldCompressLayers() bool {
+	return d.unpackedDest.ShouldCompressLayers()
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (d *ociArchiveImageDestination) AcceptsForeignLayerURLs() bool {
+	return d.unpackedDest.AcceptsForeignLayerURLs()
+}
+
+// MustMatchRuntimeOS returns true iff the destination can store only images targeted for the current runtime OS. False otherwise
+func (d *ociArchiveImageDestination) MustMatchRuntimeOS() bool {
+	return d.unpackedDest.MustMatchRuntimeOS()
+}
+
+// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+// inputInfo.Size is the expected length of stream, if known.
+func (d *ociArchiveImageDestination) PutBlob(stream io.Reader, inputInfo types.BlobInfo) (types.BlobInfo, error) {
+	return d.unpackedDest.PutBlob(stream, inputInfo)
+}
+
+// HasBlob returns true iff the image destination already contains a blob with the matching digest which can be reapplied using ReapplyBlob
+func (d *ociArchiveImageDestination) HasBlob(info types.BlobInfo) (bool, int64, error) {
+	return d.unpackedDest.HasBlob(info)
+}
+
+func (d *ociArchiveImageDestination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
+	return d.unpackedDest.ReapplyBlob(info)
+}
+
+// PutManifest writes manifest to the destination
+func (d *ociArchiveImageDestination) PutManifest(m []byte) error {
+	return d.unpackedDest.PutManifest(m)
+}
+
+func (d *ociArchiveImageDestination) PutSignatures(signatures [][]byte) error {
+	return d.unpackedDest.PutSignatures(signatures)
+}
+
+// Commit marks the process of storing the image as successful and asks for the image to be persisted
+// after the directory is made, it is tarred up into a file and the directory is deleted
+func (d *ociArchiveImageDestination) Commit() error {
+	if err := d.unpackedDest.Commit(); err != nil {
+		return errors.Wrapf(err, "error storing image %q", d.ref.image)
+	}
+
+	// path of directory to tar up
+	src := d.tempDirRef.tempDirectory
+	// path to save tarred up file
+	dst := d.ref.resolvedFile
+	return tarDirectory(src, dst)
+}
+
+// tar converts the directory at src and saves it to dst
+func tarDirectory(src, dst string) error {
+	// input is a stream of bytes from the archive of the directory at path
+	input, err := archive.Tar(src, archive.Uncompressed)
+	if err != nil {
+		return errors.Wrapf(err, "error retrieving stream of bytes from %q", src)
+	}
+
+	// creates the tar file
+	outFile, err := os.Create(dst)
+	if err != nil {
+		return errors.Wrapf(err, "error creating tar file %q", dst)
+	}
+	defer outFile.Close()
+
+	// copies the contents of the directory to the tar file
+	_, err = io.Copy(outFile, input)
+
+	return err
+}

vendor/github.com/containers/image/oci/archive/oci_src.go

@@ -0,0 +1,95 @@
+package archive
+
+import (
+	"context"
+	"io"
+
+	ocilayout "github.com/containers/image/oci/layout"
+	"github.com/containers/image/types"
+	digest "github.com/opencontainers/go-digest"
+	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/pkg/errors"
+)
+
+type ociArchiveImageSource struct {
+	ref         ociArchiveReference
+	unpackedSrc types.ImageSource
+	tempDirRef  tempDirOCIRef
+}
+
+// newImageSource returns an ImageSource for reading from an existing directory.
+// newImageSource untars the file and saves it in a temp directory
+func newImageSource(ctx *types.SystemContext, ref ociArchiveReference) (types.ImageSource, error) {
+	tempDirRef, err := createUntarTempDir(ref)
+	if err != nil {
+		return nil, errors.Wrap(err, "error creating temp directory")
+	}
+
+	unpackedSrc, err := tempDirRef.ociRefExtracted.NewImageSource(ctx)
+	if err != nil {
+		if err := tempDirRef.deleteTempDir(); err != nil {
+			return nil, errors.Wrapf(err, "error deleting temp directory", tempDirRef.tempDirectory)
+		}
+		return nil, err
+	}
+	return &ociArchiveImageSource{ref: ref,
+		unpackedSrc: unpackedSrc,
+		tempDirRef:  tempDirRef}, nil
+}
+
+// LoadManifestDescriptor loads the manifest
+func LoadManifestDescriptor(imgRef types.ImageReference) (imgspecv1.Descriptor, error) {
+	ociArchRef, ok := imgRef.(ociArchiveReference)
+	if !ok {
+		return imgspecv1.Descriptor{}, errors.Errorf("error typecasting, need type ociArchiveReference")
+	}
+	tempDirRef, err := createUntarTempDir(ociArchRef)
+	if err != nil {
+		return imgspecv1.Descriptor{}, errors.Wrap(err, "error creating temp directory")
+	}
+	defer tempDirRef.deleteTempDir()
+
+	descriptor, err := ocilayout.LoadManifestDescriptor(tempDirRef.ociRefExtracted)
+	if err != nil {
+		return imgspecv1.Descriptor{}, errors.Wrap(err, "error loading index")
+	}
+	return descriptor, nil
+}
+
+// Reference returns the reference used to set up this source.
+func (s *ociArchiveImageSource) Reference() types.ImageReference {
+	return s.ref
+}
+
+// Close removes resources associated with an initialized ImageSource, if any.
+// Close deletes the temporary directory at dst
+func (s *ociArchiveImageSource) Close() error {
+	defer s.tempDirRef.deleteTempDir()
+	return s.unpackedSrc.Close()
+}
+
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
+// If instanceDigest is not nil, it contains a digest of the specific manifest instance to retrieve (when the primary manifest is a manifest list);
+// this never happens if the primary manifest is not a manifest list (e.g. if the source never returns manifest lists).
+func (s *ociArchiveImageSource) GetManifest(instanceDigest *digest.Digest) ([]byte, string, error) {
+	return s.unpackedSrc.GetManifest(instanceDigest)
+}
+
+// GetBlob returns a stream for the specified blob, and the blob's size.
+func (s *ociArchiveImageSource) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
+	return s.unpackedSrc.GetBlob(info)
+}
+
+// GetSignatures returns the image's signatures.  It may use a remote (= slow) service.
+// If instanceDigest is not nil, it contains a digest of the specific manifest instance to retrieve signatures for
+// (when the primary manifest is a manifest list); this never happens if the primary manifest is not a manifest list
+// (e.g. if the source never returns manifest lists).
+func (s *ociArchiveImageSource) GetSignatures(ctx context.Context, instanceDigest *digest.Digest) ([][]byte, error) {
+	return s.unpackedSrc.GetSignatures(ctx, instanceDigest)
+}
+
+// LayerInfosForCopy() returns updated layer info that should be used when reading, in preference to values in the manifest, if specified.
+func (s *ociArchiveImageSource) LayerInfosForCopy() []types.BlobInfo {
+	return nil
+}

vendor/github.com/containers/image/oci/archive/oci_transport.go

@@ -0,0 +1,190 @@
+package archive
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
+
+	"github.com/containers/image/directory/explicitfilepath"
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/image"
+	"github.com/containers/image/internal/tmpdir"
+	"github.com/containers/image/oci/internal"
+	ocilayout "github.com/containers/image/oci/layout"
+	"github.com/containers/image/transports"
+	"github.com/containers/image/types"
+	"github.com/containers/storage/pkg/archive"
+	"github.com/pkg/errors"
+)
+
+func init() {
+	transports.Register(Transport)
+}
+
+// Transport is an ImageTransport for OCI archive
+// it creates an oci-archive tar file by calling into the OCI transport
+// tarring the directory created by oci and deleting the directory
+var Transport = ociArchiveTransport{}
+
+type ociArchiveTransport struct{}
+
+// ociArchiveReference is an ImageReference for OCI Archive paths
+type ociArchiveReference struct {
+	file         string
+	resolvedFile string
+	image        string
+}
+
+func (t ociArchiveTransport) Name() string {
+	return "oci-archive"
+}
+
+// ParseReference converts a string, which should not start with the ImageTransport.Name prefix
+// into an ImageReference.
+func (t ociArchiveTransport) ParseReference(reference string) (types.ImageReference, error) {
+	return ParseReference(reference)
+}
+
+// ValidatePolicyConfigurationScope checks that scope is a valid name for a signature.PolicyTransportScopes keys
+func (t ociArchiveTransport) ValidatePolicyConfigurationScope(scope string) error {
+	return internal.ValidateScope(scope)
+}
+
+// ParseReference converts a string, which should not start with the ImageTransport.Name prefix, into an OCI ImageReference.
+func ParseReference(reference string) (types.ImageReference, error) {
+	file, image := internal.SplitPathAndImage(reference)
+	return NewReference(file, image)
+}
+
+// NewReference returns an OCI reference for a file and a image.
+func NewReference(file, image string) (types.ImageReference, error) {
+	resolved, err := explicitfilepath.ResolvePathToFullyExplicit(file)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := internal.ValidateOCIPath(file); err != nil {
+		return nil, err
+	}
+
+	if err := internal.ValidateImageName(image); err != nil {
+		return nil, err
+	}
+
+	return ociArchiveReference{file: file, resolvedFile: resolved, image: image}, nil
+}
+
+func (ref ociArchiveReference) Transport() types.ImageTransport {
+	return Transport
+}
+
+// StringWithinTransport returns a string representation of the reference, which MUST be such that
+// reference.Transport().ParseReference(reference.StringWithinTransport()) returns an equivalent reference.
+func (ref ociArchiveReference) StringWithinTransport() string {
+	return fmt.Sprintf("%s:%s", ref.file, ref.image)
+}
+
+// DockerReference returns a Docker reference associated with this reference
+func (ref ociArchiveReference) DockerReference() reference.Named {
+	return nil
+}
+
+// PolicyConfigurationIdentity returns a string representation of the reference, suitable for policy lookup.
+func (ref ociArchiveReference) PolicyConfigurationIdentity() string {
+	// NOTE: ref.image is not a part of the image identity, because "$dir:$someimage" and "$dir:" may mean the
+	// same image and the two can’t be statically disambiguated.  Using at least the repository directory is
+	// less granular but hopefully still useful.
+	return fmt.Sprintf("%s", ref.resolvedFile)
+}
+
+// PolicyConfigurationNamespaces returns a list of other policy configuration namespaces to search
+// for if explicit configuration for PolicyConfigurationIdentity() is not set
+func (ref ociArchiveReference) PolicyConfigurationNamespaces() []string {
+	res := []string{}
+	path := ref.resolvedFile
+	for {
+		lastSlash := strings.LastIndex(path, "/")
+		// Note that we do not include "/"; it is redundant with the default "" global default,
+		// and rejected by ociTransport.ValidatePolicyConfigurationScope above.
+		if lastSlash == -1 || path == "/" {
+			break
+		}
+		res = append(res, path)
+		path = path[:lastSlash]
+	}
+	return res
+}
+
+// NewImage returns a types.ImageCloser for this reference, possibly specialized for this ImageTransport.
+// The caller must call .Close() on the returned ImageCloser.
+// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage.
+// WARNING: This may not do the right thing for a manifest list, see image.FromSource for details.
+func (ref ociArchiveReference) NewImage(ctx *types.SystemContext) (types.ImageCloser, error) {
+	src, err := newImageSource(ctx, ref)
+	if err != nil {
+		return nil, err
+	}
+	return image.FromSource(ctx, src)
+}
+
+// NewImageSource returns a types.ImageSource for this reference.
+// The caller must call .Close() on the returned ImageSource.
+func (ref ociArchiveReference) NewImageSource(ctx *types.SystemContext) (types.ImageSource, error) {
+	return newImageSource(ctx, ref)
+}
+
+// NewImageDestination returns a types.ImageDestination for this reference.
+// The caller must call .Close() on the returned ImageDestination.
+func (ref ociArchiveReference) NewImageDestination(ctx *types.SystemContext) (types.ImageDestination, error) {
+	return newImageDestination(ctx, ref)
+}
+
+// DeleteImage deletes the named image from the registry, if supported.
+func (ref ociArchiveReference) DeleteImage(ctx *types.SystemContext) error {
+	return errors.Errorf("Deleting images not implemented for oci: images")
+}
+
+// struct to store the ociReference and temporary directory returned by createOCIRef
+type tempDirOCIRef struct {
+	tempDirectory   string
+	ociRefExtracted types.ImageReference
+}
+
+// deletes the temporary directory created
+func (t *tempDirOCIRef) deleteTempDir() error {
+	return os.RemoveAll(t.tempDirectory)
+}
+
+// createOCIRef creates the oci reference of the image
+func createOCIRef(image string) (tempDirOCIRef, error) {
+	dir, err := ioutil.TempDir(tmpdir.TemporaryDirectoryForBigFiles(), "oci")
+	if err != nil {
+		return tempDirOCIRef{}, errors.Wrapf(err, "error creating temp directory")
+	}
+	ociRef, err := ocilayout.NewReference(dir, image)
+	if err != nil {
+		return tempDirOCIRef{}, err
+	}
+
+	tempDirRef := tempDirOCIRef{tempDirectory: dir, ociRefExtracted: ociRef}
+	return tempDirRef, nil
+}
+
+// creates the temporary directory and copies the tarred content to it
+func createUntarTempDir(ref ociArchiveReference) (tempDirOCIRef, error) {
+	tempDirRef, err := createOCIRef(ref.image)
+	if err != nil {
+		return tempDirOCIRef{}, errors.Wrap(err, "error creating oci reference")
+	}
+	src := ref.resolvedFile
+	dst := tempDirRef.tempDirectory
+	if err := archive.UntarPath(src, dst); err != nil {
+		if err := tempDirRef.deleteTempDir(); err != nil {
+			return tempDirOCIRef{}, errors.Wrapf(err, "error deleting temp directory %q", tempDirRef.tempDirectory)
+		}
+		return tempDirOCIRef{}, errors.Wrapf(err, "error untarring file %q", tempDirRef.tempDirectory)
+	}
+	return tempDirRef, nil
+}

vendor/github.com/containers/image/oci/internal/oci_util.go

@@ -0,0 +1,126 @@
+package internal
+
+import (
+	"github.com/pkg/errors"
+	"path/filepath"
+	"regexp"
+	"runtime"
+	"strings"
+)
+
+// annotation spex from https://github.com/opencontainers/image-spec/blob/master/annotations.md#pre-defined-annotation-keys
+const (
+	separator = `(?:[-._:@+]|--)`
+	alphanum  = `(?:[A-Za-z0-9]+)`
+	component = `(?:` + alphanum + `(?:` + separator + alphanum + `)*)`
+)
+
+var refRegexp = regexp.MustCompile(`^` + component + `(?:/` + component + `)*$`)
+var windowsRefRegexp = regexp.MustCompile(`^([a-zA-Z]:\\.+?):(.*)$`)
+
+// ValidateImageName returns nil if the image name is empty or matches the open-containers image name specs.
+// In any other case an error is returned.
+func ValidateImageName(image string) error {
+	if len(image) == 0 {
+		return nil
+	}
+
+	var err error
+	if !refRegexp.MatchString(image) {
+		err = errors.Errorf("Invalid image %s", image)
+	}
+	return err
+}
+
+// SplitPathAndImage tries to split the provided OCI reference into the OCI path and image.
+// Neither path nor image parts are validated at this stage.
+func SplitPathAndImage(reference string) (string, string) {
+	if runtime.GOOS == "windows" {
+		return splitPathAndImageWindows(reference)
+	}
+	return splitPathAndImageNonWindows(reference)
+}
+
+func splitPathAndImageWindows(reference string) (string, string) {
+	groups := windowsRefRegexp.FindStringSubmatch(reference)
+	// nil group means no match
+	if groups == nil {
+		return reference, ""
+	}
+
+	// we expect three elements. First one full match, second the capture group for the path and
+	// the third the capture group for the image
+	if len(groups) != 3 {
+		return reference, ""
+	}
+	return groups[1], groups[2]
+}
+
+func splitPathAndImageNonWindows(reference string) (string, string) {
+	sep := strings.SplitN(reference, ":", 2)
+	path := sep[0]
+
+	var image string
+	if len(sep) == 2 {
+		image = sep[1]
+	}
+	return path, image
+}
+
+// ValidateOCIPath takes the OCI path and validates it.
+func ValidateOCIPath(path string) error {
+	if runtime.GOOS == "windows" {
+		// On Windows we must allow for a ':' as part of the path
+		if strings.Count(path, ":") > 1 {
+			return errors.Errorf("Invalid OCI reference: path %s contains more than one colon", path)
+		}
+	} else {
+		if strings.Contains(path, ":") {
+			return errors.Errorf("Invalid OCI reference: path %s contains a colon", path)
+		}
+	}
+	return nil
+}
+
+// ValidateScope validates a policy configuration scope for an OCI transport.
+func ValidateScope(scope string) error {
+	var err error
+	if runtime.GOOS == "windows" {
+		err = validateScopeWindows(scope)
+	} else {
+		err = validateScopeNonWindows(scope)
+	}
+	if err != nil {
+		return err
+	}
+
+	cleaned := filepath.Clean(scope)
+	if cleaned != scope {
+		return errors.Errorf(`Invalid scope %s: Uses non-canonical path format, perhaps try with path %s`, scope, cleaned)
+	}
+
+	return nil
+}
+
+func validateScopeWindows(scope string) error {
+	matched, _ := regexp.Match(`^[a-zA-Z]:\\`, []byte(scope))
+	if !matched {
+		return errors.Errorf("Invalid scope '%s'. Must be an absolute path", scope)
+	}
+
+	return nil
+}
+
+func validateScopeNonWindows(scope string) error {
+	if !strings.HasPrefix(scope, "/") {
+		return errors.Errorf("Invalid scope %s: must be an absolute path", scope)
+	}
+
+	// Refuse also "/", otherwise "/" and "" would have the same semantics,
+	// and "" could be unexpectedly shadowed by the "/" entry.
+	if scope == "/" {
+		return errors.New(`Invalid scope "/": Use the generic default scope ""`)
+	}
+
+	return nil
+}

vendor/github.com/containers/image/oci/layout/oci_dest.go

@@ -0,0 +1,294 @@
+package layout
+
+import (
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/pkg/errors"
+
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/types"
+	"github.com/opencontainers/go-digest"
+	imgspec "github.com/opencontainers/image-spec/specs-go"
+	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+type ociImageDestination struct {
+	ref           ociReference
+	index         imgspecv1.Index
+	sharedBlobDir string
+}
+
+// newImageDestination returns an ImageDestination for writing to an existing directory.
+func newImageDestination(ctx *types.SystemContext, ref ociReference) (types.ImageDestination, error) {
+	if ref.image == "" {
+		return nil, errors.Errorf("cannot save image with empty image.ref.name")
+	}
+
+	var index *imgspecv1.Index
+	if indexExists(ref) {
+		var err error
+		index, err = ref.getIndex()
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		index = &imgspecv1.Index{
+			Versioned: imgspec.Versioned{
+				SchemaVersion: 2,
+			},
+		}
+	}
+
+	d := &ociImageDestination{ref: ref, index: *index}
+	if ctx != nil {
+		d.sharedBlobDir = ctx.OCISharedBlobDirPath
+	}
+
+	if err := ensureDirectoryExists(d.ref.dir); err != nil {
+		return nil, err
+	}
+	// Per the OCI image specification, layouts MUST have a "blobs" subdirectory,
+	// but it MAY be empty (e.g. if we never end up calling PutBlob)
+	// https://github.com/opencontainers/image-spec/blame/7c889fafd04a893f5c5f50b7ab9963d5d64e5242/image-layout.md#L19
+	if err := ensureDirectoryExists(filepath.Join(d.ref.dir, "blobs")); err != nil {
+		return nil, err
+	}
+	return d, nil
+}
+
+// Reference returns the reference used to set up this destination.  Note that this should directly correspond to user's intent,
+// e.g. it should use the public hostname instead of the result of resolving CNAMEs or following redirects.
+func (d *ociImageDestination) Reference() types.ImageReference {
+	return d.ref
+}
+
+// Close removes resources associated with an initialized ImageDestination, if any.
+func (d *ociImageDestination) Close() error {
+	return nil
+}
+
+func (d *ociImageDestination) SupportedManifestMIMETypes() []string {
+	return []string{
+		imgspecv1.MediaTypeImageManifest,
+	}
+}
+
+// SupportsSignatures returns an error (to be displayed to the user) if the destination certainly can't store signatures.
+// Note: It is still possible for PutSignatures to fail if SupportsSignatures returns nil.
+func (d *ociImageDestination) SupportsSignatures() error {
+	return errors.Errorf("Pushing signatures for OCI images is not supported")
+}
+
+// ShouldCompressLayers returns true iff it is desirable to compress layer blobs written to this destination.
+func (d *ociImageDestination) ShouldCompressLayers() bool {
+	return true
+}
+
+// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
+// uploaded to the image destination, true otherwise.
+func (d *ociImageDestination) AcceptsForeignLayerURLs() bool {
+	return true
+}
+
+// MustMatchRuntimeOS returns true iff the destination can store only images targeted for the current runtime OS. False otherwise.
+func (d *ociImageDestination) MustMatchRuntimeOS() bool {
+	return false
+}
+
+// PutBlob writes contents of stream and returns data representing the result (with all data filled in).
+// inputInfo.Digest can be optionally provided if known; it is not mandatory for the implementation to verify it.
+// inputInfo.Size is the expected length of stream, if known.
+// WARNING: The contents of stream are being verified on the fly.  Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
+// to any other readers for download using the supplied digest.
+// If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlob MUST 1) fail, and 2) delete any data stored so far.
+func (d *ociImageDestination) PutBlob(stream io.Reader, inputInfo types.BlobInfo) (types.BlobInfo, error) {
+	blobFile, err := ioutil.TempFile(d.ref.dir, "oci-put-blob")
+	if err != nil {
+		return types.BlobInfo{}, err
+	}
+	succeeded := false
+	explicitClosed := false
+	defer func() {
+		if !explicitClosed {
+			blobFile.Close()
+		}
+		if !succeeded {
+			os.Remove(blobFile.Name())
+		}
+	}()
+
+	digester := digest.Canonical.Digester()
+	tee := io.TeeReader(stream, digester.Hash())
+
+	size, err := io.Copy(blobFile, tee)
+	if err != nil {
+		return types.BlobInfo{}, err
+	}
+	computedDigest := digester.Digest()
+	if inputInfo.Size != -1 && size != inputInfo.Size {
+		return types.BlobInfo{}, errors.Errorf("Size mismatch when copying %s, expected %d, got %d", computedDigest, inputInfo.Size, size)
+	}
+	if err := blobFile.Sync(); err != nil {
+		return types.BlobInfo{}, err
+	}
+
+	// On POSIX systems, blobFile was created with mode 0600, so we need to make it readable.
+	// On Windows, the “permissions of newly created files” argument to syscall.Open is
+	// ignored and the file is already readable; besides, blobFile.Chmod, i.e. syscall.Fchmod,
+	// always fails on Windows.
+	if runtime.GOOS != "windows" {
+		if err := blobFile.Chmod(0644); err != nil {
+			return types.BlobInfo{}, err
+		}
+	}
+
+	blobPath, err := d.ref.blobPath(computedDigest, d.sharedBlobDir)
+	if err != nil {
+		return types.BlobInfo{}, err
+	}
+	if err := ensureParentDirectoryExists(blobPath); err != nil {
+		return types.BlobInfo{}, err
+	}
+
+	// need to explicitly close the file, since a rename won't otherwise not work on Windows
+	blobFile.Close()
+	explicitClosed = true
+	if err := os.Rename(blobFile.Name(), blobPath); err != nil {
+		return types.BlobInfo{}, err
+	}
+	succeeded = true
+	return types.BlobInfo{Digest: computedDigest, Size: size}, nil
+}
+
+// HasBlob returns true iff the image destination already contains a blob with the matching digest which can be reapplied using ReapplyBlob.
+// Unlike PutBlob, the digest can not be empty.  If HasBlob returns true, the size of the blob must also be returned.
+// If the destination does not contain the blob, or it is unknown, HasBlob ordinarily returns (false, -1, nil);
+// it returns a non-nil error only on an unexpected failure.
+func (d *ociImageDestination) HasBlob(info types.BlobInfo) (bool, int64, error) {
+	if info.Digest == "" {
+		return false, -1, errors.Errorf(`"Can not check for a blob with unknown digest`)
+	}
+	blobPath, err := d.ref.blobPath(info.Digest, d.sharedBlobDir)
+	if err != nil {
+		return false, -1, err
+	}
+	finfo, err := os.Stat(blobPath)
+	if err != nil && os.IsNotExist(err) {
+		return false, -1, nil
+	}
+	if err != nil {
+		return false, -1, err
+	}
+	return true, finfo.Size(), nil
+}
+
+func (d *ociImageDestination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
+	return info, nil
+}
+
+// PutManifest writes manifest to the destination.
+// FIXME? This should also receive a MIME type if known, to differentiate between schema versions.
+// If the destination is in principle available, refuses this manifest type (e.g. it does not recognize the schema),
+// but may accept a different manifest type, the returned error must be an ManifestTypeRejectedError.
+func (d *ociImageDestination) PutManifest(m []byte) error {
+	digest, err := manifest.Digest(m)
+	if err != nil {
+		return err
+	}
+	desc := imgspecv1.Descriptor{}
+	desc.Digest = digest
+	// TODO(runcom): beaware and add support for OCI manifest list
+	desc.MediaType = imgspecv1.MediaTypeImageManifest
+	desc.Size = int64(len(m))
+
+	blobPath, err := d.ref.blobPath(digest, d.sharedBlobDir)
+	if err != nil {
+		return err
+	}
+	if err := ensureParentDirectoryExists(blobPath); err != nil {
+		return err
+	}
+	if err := ioutil.WriteFile(blobPath, m, 0644); err != nil {
+		return err
+	}
+
+	if d.ref.image == "" {
+		return errors.Errorf("cannot save image with empyt image.ref.name")
+	}
+
+	annotations := make(map[string]string)
+	annotations["org.opencontainers.image.ref.name"] = d.ref.image
+	desc.Annotations = annotations
+	desc.Platform = &imgspecv1.Platform{
+		Architecture: runtime.GOARCH,
+		OS:           runtime.GOOS,
+	}
+	d.addManifest(&desc)
+
+	return nil
+}
+
+func (d *ociImageDestination) addManifest(desc *imgspecv1.Descriptor) {
+	for i, manifest := range d.index.Manifests {
+		if manifest.Annotations["org.opencontainers.image.ref.name"] == desc.Annotations["org.opencontainers.image.ref.name"] {
+			// TODO Should there first be a cleanup based on the descriptor we are going to replace?
+			d.index.Manifests[i] = *desc
+			return
+		}
+	}
+	d.index.Manifests = append(d.index.Manifests, *desc)
+}
+
+func (d *ociImageDestination) PutSignatures(signatures [][]byte) error {
+	if len(signatures) != 0 {
+		return errors.Errorf("Pushing signatures for OCI images is not supported")
+	}
+	return nil
+}
+
+// Commit marks the process of storing the image as successful and asks for the image to be persisted.
+// WARNING: This does not have any transactional semantics:
+// - Uploaded data MAY be visible to others before Commit() is called
+// - Uploaded data MAY be removed or MAY remain around if Close() is called without Commit() (i.e. rollback is allowed but not guaranteed)
+func (d *ociImageDestination) Commit() error {
+	if err := ioutil.WriteFile(d.ref.ociLayoutPath(), []byte(`{"imageLayoutVersion": "1.0.0"}`), 0644); err != nil {
+		return err
+	}
+	indexJSON, err := json.Marshal(d.index)
+	if err != nil {
+		return err
+	}
+	return ioutil.WriteFile(d.ref.indexPath(), indexJSON, 0644)
+}
+
+func ensureDirectoryExists(path string) error {
+	if _, err := os.Stat(path); err != nil && os.IsNotExist(err) {
+		if err := os.MkdirAll(path, 0755); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// ensureParentDirectoryExists ensures the parent of the supplied path exists.
+func ensureParentDirectoryExists(path string) error {
+	return ensureDirectoryExists(filepath.Dir(path))
+}
+
+// indexExists checks whether the index location specified in the OCI reference exists.
+// The implementation is opinionated, since in case of unexpected errors false is returned
+func indexExists(ref ociReference) bool {
+	_, err := os.Stat(ref.indexPath())
+	if err == nil {
+		return true
+	}
+	if os.IsNotExist(err) {
+		return false
+	}
+	return true
+}

vendor/github.com/containers/image/oci/layout/oci_src.go

@@ -0,0 +1,157 @@
+package layout
+
+import (
+	"context"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"strconv"
+
+	"github.com/containers/image/pkg/tlsclientconfig"
+	"github.com/containers/image/types"
+	"github.com/docker/go-connections/tlsconfig"
+	"github.com/opencontainers/go-digest"
+	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/pkg/errors"
+)
+
+type ociImageSource struct {
+	ref           ociReference
+	descriptor    imgspecv1.Descriptor
+	client        *http.Client
+	sharedBlobDir string
+}
+
+// newImageSource returns an ImageSource for reading from an existing directory.
+func newImageSource(ctx *types.SystemContext, ref ociReference) (types.ImageSource, error) {
+	tr := tlsclientconfig.NewTransport()
+	tr.TLSClientConfig = tlsconfig.ServerDefault()
+
+	if ctx != nil && ctx.OCICertPath != "" {
+		if err := tlsclientconfig.SetupCertificates(ctx.OCICertPath, tr.TLSClientConfig); err != nil {
+			return nil, err
+		}
+		tr.TLSClientConfig.InsecureSkipVerify = ctx.OCIInsecureSkipTLSVerify
+	}
+
+	client := &http.Client{}
+	client.Transport = tr
+	descriptor, err := ref.getManifestDescriptor()
+	if err != nil {
+		return nil, err
+	}
+	d := &ociImageSource{ref: ref, descriptor: descriptor, client: client}
+	if ctx != nil {
+		// TODO(jonboulle): check dir existence?
+		d.sharedBlobDir = ctx.OCISharedBlobDirPath
+	}
+	return d, nil
+}
+
+// Reference returns the reference used to set up this source.
+func (s *ociImageSource) Reference() types.ImageReference {
+	return s.ref
+}
+
+// Close removes resources associated with an initialized ImageSource, if any.
+func (s *ociImageSource) Close() error {
+	return nil
+}
+
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
+// If instanceDigest is not nil, it contains a digest of the specific manifest instance to retrieve (when the primary manifest is a manifest list);
+// this never happens if the primary manifest is not a manifest list (e.g. if the source never returns manifest lists).
+func (s *ociImageSource) GetManifest(instanceDigest *digest.Digest) ([]byte, string, error) {
+	var dig digest.Digest
+	var mimeType string
+	if instanceDigest == nil {
+		dig = digest.Digest(s.descriptor.Digest)
+		mimeType = s.descriptor.MediaType
+	} else {
+		dig = *instanceDigest
+		// XXX: instanceDigest means that we don't immediately have the context of what
+		//      mediaType the manifest has. In OCI this means that we don't know
+		//      what reference it came from, so we just *assume* that its
+		//      MediaTypeImageManifest.
+		// FIXME: We should actually be able to look up the manifest in the index,
+		// and see the MIME type there.
+		mimeType = imgspecv1.MediaTypeImageManifest
+	}
+
+	manifestPath, err := s.ref.blobPath(dig, s.sharedBlobDir)
+	if err != nil {
+		return nil, "", err
+	}
+	m, err := ioutil.ReadFile(manifestPath)
+	if err != nil {
+		return nil, "", err
+	}
+
+	return m, mimeType, nil
+}
+
+// GetBlob returns a stream for the specified blob, and the blob's size.
+func (s *ociImageSource) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
+	if len(info.URLs) != 0 {
+		return s.getExternalBlob(info.URLs)
+	}
+
+	path, err := s.ref.blobPath(info.Digest, s.sharedBlobDir)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	r, err := os.Open(path)
+	if err != nil {
+		return nil, 0, err
+	}
+	fi, err := r.Stat()
+	if err != nil {
+		return nil, 0, err
+	}
+	return r, fi.Size(), nil
+}
+
+// GetSignatures returns the image's signatures.  It may use a remote (= slow) service.
+// If instanceDigest is not nil, it contains a digest of the specific manifest instance to retrieve signatures for
+// (when the primary manifest is a manifest list); this never happens if the primary manifest is not a manifest list
+// (e.g. if the source never returns manifest lists).
+func (s *ociImageSource) GetSignatures(ctx context.Context, instanceDigest *digest.Digest) ([][]byte, error) {
+	return [][]byte{}, nil
+}
+
+func (s *ociImageSource) getExternalBlob(urls []string) (io.ReadCloser, int64, error) {
+	errWrap := errors.New("failed fetching external blob from all urls")
+	for _, url := range urls {
+		resp, err := s.client.Get(url)
+		if err != nil {
+			errWrap = errors.Wrapf(errWrap, "fetching %s failed %s", url, err.Error())
+			continue
+		}
+
+		if resp.StatusCode != http.StatusOK {
+			resp.Body.Close()
+			errWrap = errors.Wrapf(errWrap, "fetching %s failed, response code not 200", url)
+			continue
+		}
+
+		return resp.Body, getBlobSize(resp), nil
+	}
+
+	return nil, 0, errWrap
+}
+
+// LayerInfosForCopy() returns updated layer info that should be used when reading, in preference to values in the manifest, if specified.
+func (s *ociImageSource) LayerInfosForCopy() []types.BlobInfo {
+	return nil
+}
+
+func getBlobSize(resp *http.Response) int64 {
+	size, err := strconv.ParseInt(resp.Header.Get("Content-Length"), 10, 64)
+	if err != nil {
+		size = -1
+	}
+	return size
+}

vendor/github.com/containers/image/oci/layout/oci_transport.go

@@ -0,0 +1,255 @@
+package layout
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/containers/image/directory/explicitfilepath"
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/image"
+	"github.com/containers/image/oci/internal"
+	"github.com/containers/image/transports"
+	"github.com/containers/image/types"
+	"github.com/opencontainers/go-digest"
+	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/pkg/errors"
+)
+
+func init() {
+	transports.Register(Transport)
+}
+
+// Transport is an ImageTransport for OCI directories.
+var Transport = ociTransport{}
+
+type ociTransport struct{}
+
+func (t ociTransport) Name() string {
+	return "oci"
+}
+
+// ParseReference converts a string, which should not start with the ImageTransport.Name prefix, into an ImageReference.
+func (t ociTransport) ParseReference(reference string) (types.ImageReference, error) {
+	return ParseReference(reference)
+}
+
+// ValidatePolicyConfigurationScope checks that scope is a valid name for a signature.PolicyTransportScopes keys
+// (i.e. a valid PolicyConfigurationIdentity() or PolicyConfigurationNamespaces() return value).
+// It is acceptable to allow an invalid value which will never be matched, it can "only" cause user confusion.
+// scope passed to this function will not be "", that value is always allowed.
+func (t ociTransport) ValidatePolicyConfigurationScope(scope string) error {
+	return internal.ValidateScope(scope)
+}
+
+// ociReference is an ImageReference for OCI directory paths.
+type ociReference struct {
+	// Note that the interpretation of paths below depends on the underlying filesystem state, which may change under us at any time!
+	// Either of the paths may point to a different, or no, inode over time.  resolvedDir may contain symbolic links, and so on.
+
+	// Generally we follow the intent of the user, and use the "dir" member for filesystem operations (e.g. the user can use a relative path to avoid
+	// being exposed to symlinks and renames in the parent directories to the working directory).
+	// (But in general, we make no attempt to be completely safe against concurrent hostile filesystem modifications.)
+	dir         string // As specified by the user. May be relative, contain symlinks, etc.
+	resolvedDir string // Absolute path with no symlinks, at least at the time of its creation. Primarily used for policy namespaces.
+	image       string // If image=="", it means the only image in the index.json is used
+}
+
+// ParseReference converts a string, which should not start with the ImageTransport.Name prefix, into an OCI ImageReference.
+func ParseReference(reference string) (types.ImageReference, error) {
+	dir, image := internal.SplitPathAndImage(reference)
+	return NewReference(dir, image)
+}
+
+// NewReference returns an OCI reference for a directory and a image.
+//
+// We do not expose an API supplying the resolvedDir; we could, but recomputing it
+// is generally cheap enough that we prefer being confident about the properties of resolvedDir.
+func NewReference(dir, image string) (types.ImageReference, error) {
+	resolved, err := explicitfilepath.ResolvePathToFullyExplicit(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := internal.ValidateOCIPath(dir); err != nil {
+		return nil, err
+	}
+
+	if err = internal.ValidateImageName(image); err != nil {
+		return nil, err
+	}
+
+	return ociReference{dir: dir, resolvedDir: resolved, image: image}, nil
+}
+
+func (ref ociReference) Transport() types.ImageTransport {
+	return Transport
+}
+
+// StringWithinTransport returns a string representation of the reference, which MUST be such that
+// reference.Transport().ParseReference(reference.StringWithinTransport()) returns an equivalent reference.
+// NOTE: The returned string is not promised to be equal to the original input to ParseReference;
+// e.g. default attribute values omitted by the user may be filled in in the return value, or vice versa.
+// WARNING: Do not use the return value in the UI to describe an image, it does not contain the Transport().Name() prefix.
+func (ref ociReference) StringWithinTransport() string {
+	return fmt.Sprintf("%s:%s", ref.dir, ref.image)
+}
+
+// DockerReference returns a Docker reference associated with this reference
+// (fully explicit, i.e. !reference.IsNameOnly, but reflecting user intent,
+// not e.g. after redirect or alias processing), or nil if unknown/not applicable.
+func (ref ociReference) DockerReference() reference.Named {
+	return nil
+}
+
+// PolicyConfigurationIdentity returns a string representation of the reference, suitable for policy lookup.
+// This MUST reflect user intent, not e.g. after processing of third-party redirects or aliases;
+// The value SHOULD be fully explicit about its semantics, with no hidden defaults, AND canonical
+// (i.e. various references with exactly the same semantics should return the same configuration identity)
+// It is fine for the return value to be equal to StringWithinTransport(), and it is desirable but
+// not required/guaranteed that it will be a valid input to Transport().ParseReference().
+// Returns "" if configuration identities for these references are not supported.
+func (ref ociReference) PolicyConfigurationIdentity() string {
+	// NOTE: ref.image is not a part of the image identity, because "$dir:$someimage" and "$dir:" may mean the
+	// same image and the two can’t be statically disambiguated.  Using at least the repository directory is
+	// less granular but hopefully still useful.
+	return fmt.Sprintf("%s", ref.resolvedDir)
+}
+
+// PolicyConfigurationNamespaces returns a list of other policy configuration namespaces to search
+// for if explicit configuration for PolicyConfigurationIdentity() is not set.  The list will be processed
+// in order, terminating on first match, and an implicit "" is always checked at the end.
+// It is STRONGLY recommended for the first element, if any, to be a prefix of PolicyConfigurationIdentity(),
+// and each following element to be a prefix of the element preceding it.
+func (ref ociReference) PolicyConfigurationNamespaces() []string {
+	res := []string{}
+	path := ref.resolvedDir
+	for {
+		lastSlash := strings.LastIndex(path, "/")
+		// Note that we do not include "/"; it is redundant with the default "" global default,
+		// and rejected by ociTransport.ValidatePolicyConfigurationScope above.
+		if lastSlash == -1 || path == "/" {
+			break
+		}
+		res = append(res, path)
+		path = path[:lastSlash]
+	}
+	return res
+}
+
+// NewImage returns a types.ImageCloser for this reference, possibly specialized for this ImageTransport.
+// The caller must call .Close() on the returned ImageCloser.
+// NOTE: If any kind of signature verification should happen, build an UnparsedImage from the value returned by NewImageSource,
+// verify that UnparsedImage, and convert it into a real Image via image.FromUnparsedImage.
+// WARNING: This may not do the right thing for a manifest list, see image.FromSource for details.
+func (ref ociReference) NewImage(ctx *types.SystemContext) (types.ImageCloser, error) {
+	src, err := newImageSource(ctx, ref)
+	if err != nil {
+		return nil, err
+	}
+	return image.FromSource(ctx, src)
+}
+
+// getIndex returns a pointer to the index references by this ociReference. If an error occurs opening an index nil is returned together
+// with an error.
+func (ref ociReference) getIndex() (*imgspecv1.Index, error) {
+	indexJSON, err := os.Open(ref.indexPath())
+	if err != nil {
+		return nil, err
+	}
+	defer indexJSON.Close()
+
+	index := &imgspecv1.Index{}
+	if err := json.NewDecoder(indexJSON).Decode(index); err != nil {
+		return nil, err
+	}
+	return index, nil
+}
+
+func (ref ociReference) getManifestDescriptor() (imgspecv1.Descriptor, error) {
+	index, err := ref.getIndex()
+	if err != nil {
+		return imgspecv1.Descriptor{}, err
+	}
+
+	var d *imgspecv1.Descriptor
+	if ref.image == "" {
+		// return manifest if only one image is in the oci directory
+		if len(index.Manifests) == 1 {
+			d = &index.Manifests[0]
+		} else {
+			// ask user to choose image when more than one image in the oci directory
+			return imgspecv1.Descriptor{}, errors.Wrapf(err, "more than one image in oci, choose an image")
+		}
+	} else {
+		// if image specified, look through all manifests for a match
+		for _, md := range index.Manifests {
+			if md.MediaType != imgspecv1.MediaTypeImageManifest {
+				continue
+			}
+			refName, ok := md.Annotations["org.opencontainers.image.ref.name"]
+			if !ok {
+				continue
+			}
+			if refName == ref.image {
+				d = &md
+				break
+			}
+		}
+	}
+	if d == nil {
+		return imgspecv1.Descriptor{}, fmt.Errorf("no descriptor found for reference %q", ref.image)
+	}
+	return *d, nil
+}
+
+// LoadManifestDescriptor loads the manifest descriptor to be used to retrieve the image name
+// when pulling an image
+func LoadManifestDescriptor(imgRef types.ImageReference) (imgspecv1.Descriptor, error) {
+	ociRef, ok := imgRef.(ociReference)
+	if !ok {
+		return imgspecv1.Descriptor{}, errors.Errorf("error typecasting, need type ociRef")
+	}
+	return ociRef.getManifestDescriptor()
+}
+
+// NewImageSource returns a types.ImageSource for this reference.
+// The caller must call .Close() on the returned ImageSource.
+func (ref ociReference) NewImageSource(ctx *types.SystemContext) (types.ImageSource, error) {
+	return newImageSource(ctx, ref)
+}
+
+// NewImageDestination returns a types.ImageDestination for this reference.
+// The caller must call .Close() on the returned ImageDestination.
+func (ref ociReference) NewImageDestination(ctx *types.SystemContext) (types.ImageDestination, error) {
+	return newImageDestination(ctx, ref)
+}
+
+// DeleteImage deletes the named image from the registry, if supported.
+func (ref ociReference) DeleteImage(ctx *types.SystemContext) error {
+	return errors.Errorf("Deleting images not implemented for oci: images")
+}
+
+// ociLayoutPath returns a path for the oci-layout within a directory using OCI conventions.
+func (ref ociReference) ociLayoutPath() string {
+	return filepath.Join(ref.dir, "oci-layout")
+}
+
+// indexPath returns a path for the index.json within a directory using OCI conventions.
+func (ref ociReference) indexPath() string {
+	return filepath.Join(ref.dir, "index.json")
+}
+
+// blobPath returns a path for a blob within a directory using OCI image-layout conventions.
+func (ref ociReference) blobPath(digest digest.Digest, sharedBlobDir string) (string, error) {
+	if err := digest.Validate(); err != nil {
+		return "", errors.Wrapf(err, "unexpected digest reference %s", digest)
+	}
+	blobDir := filepath.Join(ref.dir, "blobs")
+	if sharedBlobDir != "" {
+		blobDir = sharedBlobDir
+	}
+	return filepath.Join(blobDir, digest.Algorithm().String(), digest.Hex()), nil
+}