Add import gzip and bzip2 support

Signed-off-by: jokemanfire <hu.dingyang@zte.com.cn>

core/images/archive/importer.go

@@ -64,8 +64,6 @@ func WithImportCompression() ImportOpt {
 //   - existing OCI reference names are untouched
 func ImportIndex(ctx context.Context, store content.Store, reader io.Reader, opts ...ImportOpt) (ocispec.Descriptor, error) {
 	var (
-		tr = tar.NewReader(reader)
-
 		ociLayout ocispec.ImageLayout
 		mfsts     []struct {
 			Config   string
@@ -82,6 +80,12 @@ func ImportIndex(ctx context.Context, store content.Store, reader io.Reader, opt
 			return ocispec.Descriptor{}, err
 		}
 	}
+	s, err := compression.DecompressStream(reader)
+	if err != nil {
+		return ocispec.Descriptor{}, fmt.Errorf("failed to detect the format of the import file: %w", err)
+	}
+
+	tr := tar.NewReader(s)
 
 	for {
 		hdr, err := tr.Next()

pkg/archive/compression/compression.go

@@ -19,6 +19,7 @@ package compression
 import (
 	"bufio"
 	"bytes"
+	"compress/bzip2"
 	"compress/gzip"
 	"context"
 	"encoding/binary"
@@ -45,6 +46,8 @@ const (
 	Gzip
 	// Zstd is zstd compression algorithm.
 	Zstd
+	// Bzip2 is bzip2 compression algorithm
+	Bzip2
 )
 
 const (
@@ -135,8 +138,9 @@ const (
 )
 
 var (
-	gzipMagic = []byte{0x1F, 0x8B, 0x08}
-	zstdMagic = []byte{0x28, 0xb5, 0x2f, 0xfd}
+	gzipMagic  = []byte{0x1F, 0x8B, 0x08}
+	zstdMagic  = []byte{0x28, 0xb5, 0x2f, 0xfd}
+	bzip2Magic = []byte{0x42, 0x5A, 0x68}
 )
 
 type matcher = func([]byte) bool
@@ -171,8 +175,9 @@ func zstdMatcher() matcher {
 // DetectCompression detects the compression algorithm of the source.
 func DetectCompression(source []byte) Compression {
 	for compression, fn := range map[Compression]matcher{
-		Gzip: magicNumberMatcher(gzipMagic),
-		Zstd: zstdMatcher(),
+		Gzip:  magicNumberMatcher(gzipMagic),
+		Zstd:  zstdMatcher(),
+		Bzip2: magicNumberMatcher(bzip2Magic),
 	} {
 		if fn(source) {
 			return compression
@@ -230,7 +235,15 @@ func DecompressStream(archive io.Reader) (DecompressReadCloser, error) {
 				return nil
 			},
 		}, nil
-
+	case Bzip2:
+		bzip2reader := bzip2.NewReader(buf)
+		return &readCloserWrapper{
+			Reader:      bzip2reader,
+			compression: compression,
+			closer: func() error {
+				return nil
+			},
+		}, nil
 	default:
 		return nil, fmt.Errorf("unsupported compression format %s", (&compression).Extension())
 	}