motiejus/undocker
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Dropped check for the presence of .tar extension in blob names, which caused undocker to fail for newer Docker images.

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This commit is contained in:
Andrei Errapart 2024-09-10 09:21:38 +02:00 committed by Motiejus Jakštys
parent 6400df9612
commit 555983fc2e
1 changed files with 13 additions and 15 deletions
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28
rootfs/rootfs.go
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@ -40,8 +40,8 @@ func Flatten(rd io.ReadSeeker, w io.Writer) (_err error) {
var closer func() error var closer func() error
var err error var err error
// layerOffsets maps a layer name (a9b123c0daa/layer.tar) to it's offset // fileOffsets maps a file name (a9b123c0daa/layer.tar) to it's offset
layerOffsets := map[string]int64{} fileOffsets := map[string]int64{}
// manifest is the docker manifest in the image // manifest is the docker manifest in the image
var manifest dockerManifestJSON var manifest dockerManifestJSON
@ -58,31 +58,29 @@ func Flatten(rd io.ReadSeeker, w io.Writer) (_err error) {
if hdr.Typeflag != tar.TypeReg { if hdr.Typeflag != tar.TypeReg {
continue continue
} }
switch {
case filepath.Clean(hdr.Name) == _manifestJSON:
dec := json.NewDecoder(tr)
if err := dec.Decode(&manifest); err != nil {
return fmt.Errorf("decode %s: %w", _manifestJSON, err)
}
case strings.HasSuffix(hdr.Name, _tarSuffix):
here, err := rd.Seek(0, io.SeekCurrent) here, err := rd.Seek(0, io.SeekCurrent)
if err != nil { if err != nil {
return err return err
} }
layerOffsets[strings.TrimPrefix(hdr.Name, "./")] = here fileOffsets[strings.TrimPrefix(hdr.Name, "./")] = here
if filepath.Clean(hdr.Name) == _manifestJSON {
dec := json.NewDecoder(tr)
if err := dec.Decode(&manifest); err != nil {
return fmt.Errorf("decode %s: %w", _manifestJSON, err)
}
} }
} }
if err := validateManifest(layerOffsets, manifest); err != nil { if err := validateManifest(fileOffsets, manifest); err != nil {
return err return err
} }
// enumerate layers the way they would be laid down in the image // enumerate layers the way they would be laid down in the image
layers := make([]nameOffset, len(layerOffsets)) layers := make([]nameOffset, len(manifest[0].Layers))
for i, name := range manifest[0].Layers { for i, name := range manifest[0].Layers {
layers[i] = nameOffset{ layers[i] = nameOffset{
name: name, name: name,
offset: layerOffsets[strings.TrimPrefix(name, "./")], offset: fileOffsets[strings.TrimPrefix(name, "./")],
} }
} }
@ -232,7 +230,7 @@ func whiteoutDirs(whreaddir map[string]int, nlayers int) []*tree {
// validateManifest // validateManifest
func validateManifest( func validateManifest(
layerOffsets map[string]int64, fileOffsets map[string]int64,
manifest dockerManifestJSON, manifest dockerManifestJSON,
) error { ) error {
if len(manifest) == 0 { if len(manifest) == 0 {
@ -240,7 +238,7 @@ func validateManifest(
} }
for _, layer := range manifest[0].Layers { for _, layer := range manifest[0].Layers {
if _, ok := layerOffsets[layer]; !ok { if _, ok := fileOffsets[layer]; !ok {
return fmt.Errorf("%s defined in manifest, missing in tarball", layer) return fmt.Errorf("%s defined in manifest, missing in tarball", layer)
} }
} }