Support storing SHA256 checksum for files in soong_zip

Add a -sha256 argument to soong_zip that computes SHA256 checksum for
each file and stores the value in file header. The SHA information can
then be used by downstream systems that use content addressing.

Bug: 259513199
Test: zip_test.go
Test: soong_zip -o test.zip -D test_dir -sha256
Change-Id: I20e9f424bd0a4604f0dc7cc77bd65f10eb49a163
This commit is contained in:
Zhenhuang Wang
2023-01-06 20:58:01 +08:00
parent 358ba4f0d8
commit b8451b8448
3 changed files with 118 additions and 26 deletions

View File

@@ -163,6 +163,7 @@ func main() {
parallelJobs := flags.Int("parallel", runtime.NumCPU(), "number of parallel threads to use")
cpuProfile := flags.String("cpuprofile", "", "write cpu profile to file")
traceFile := flags.String("trace", "", "write trace to file")
sha256Checksum := flags.Bool("sha256", false, "add a zip header to each file containing its SHA256 digest")
flags.Var(&rootPrefix{}, "P", "path prefix within the zip at which to place files")
flags.Var(&listFiles{}, "l", "file containing list of files to zip")
@@ -224,6 +225,7 @@ func main() {
WriteIfChanged: *writeIfChanged,
StoreSymlinks: *symlinks,
IgnoreMissingFiles: *ignoreMissingFiles,
Sha256Checksum: *sha256Checksum,
})
if err != nil {
fmt.Fprintln(os.Stderr, "error:", err.Error())

View File

@@ -17,8 +17,11 @@ package zip
import (
"bytes"
"compress/flate"
"crypto/sha256"
"encoding/binary"
"errors"
"fmt"
"hash"
"hash/crc32"
"io"
"io/ioutil"
@@ -38,6 +41,14 @@ import (
"android/soong/third_party/zip"
)
// Sha256HeaderID is a custom Header ID for the `extra` field in
// the file header to store the SHA checksum.
const Sha256HeaderID = 0x4967
// Sha256HeaderSignature is the signature to verify that the extra
// data block is used to store the SHA checksum.
const Sha256HeaderSignature = 0x9514
// Block size used during parallel compression of a single file.
const parallelBlockSize = 1 * 1024 * 1024 // 1MB
@@ -231,6 +242,8 @@ type ZipWriter struct {
stderr io.Writer
fs pathtools.FileSystem
sha256Checksum bool
}
type zipEntry struct {
@@ -257,6 +270,7 @@ type ZipArgs struct {
WriteIfChanged bool
StoreSymlinks bool
IgnoreMissingFiles bool
Sha256Checksum bool
Stderr io.Writer
Filesystem pathtools.FileSystem
@@ -280,6 +294,7 @@ func zipTo(args ZipArgs, w io.Writer) error {
ignoreMissingFiles: args.IgnoreMissingFiles,
stderr: args.Stderr,
fs: args.Filesystem,
sha256Checksum: args.Sha256Checksum,
}
if z.fs == nil {
@@ -782,15 +797,17 @@ func (z *ZipWriter) writeFileContents(header *zip.FileHeader, r pathtools.Reader
// this based on actual buffer sizes in RateLimit.
ze.futureReaders = make(chan chan io.Reader, (fileSize/parallelBlockSize)+1)
// Calculate the CRC in the background, since reading the entire
// file could take a while.
// Calculate the CRC and SHA256 in the background, since reading
// the entire file could take a while.
//
// We could split this up into chunks as well, but it's faster
// than the compression. Due to the Go Zip API, we also need to
// know the result before we can begin writing the compressed
// data out to the zipfile.
//
// We calculate SHA256 only if `-sha256` is set.
wg.Add(1)
go z.crcFile(r, ze, compressChan, wg)
go z.checksumFileAsync(r, ze, compressChan, wg)
for start := int64(0); start < fileSize; start += parallelBlockSize {
sr := io.NewSectionReader(r, start, parallelBlockSize)
@@ -829,20 +846,53 @@ func (z *ZipWriter) writeFileContents(header *zip.FileHeader, r pathtools.Reader
return nil
}
func (z *ZipWriter) crcFile(r io.Reader, ze *zipEntry, resultChan chan *zipEntry, wg *sync.WaitGroup) {
func (z *ZipWriter) checksumFileAsync(r io.ReadSeeker, ze *zipEntry, resultChan chan *zipEntry, wg *sync.WaitGroup) {
defer wg.Done()
defer z.cpuRateLimiter.Finish()
z.checksumFile(r, ze)
resultChan <- ze
close(resultChan)
}
func (z *ZipWriter) checksumFile(r io.ReadSeeker, ze *zipEntry) {
crc := crc32.NewIEEE()
_, err := io.Copy(crc, r)
writers := []io.Writer{crc}
var shaHasher hash.Hash
if z.sha256Checksum && !ze.fh.Mode().IsDir() {
shaHasher = sha256.New()
writers = append(writers, shaHasher)
}
w := io.MultiWriter(writers...)
_, err := io.Copy(w, r)
if err != nil {
z.errors <- err
return
}
ze.fh.CRC32 = crc.Sum32()
resultChan <- ze
close(resultChan)
if shaHasher != nil {
z.appendSHAToExtra(ze, shaHasher.Sum(nil))
}
}
func (z *ZipWriter) appendSHAToExtra(ze *zipEntry, checksum []byte) {
// The block of SHA256 checksum consist of:
// - Header ID, equals to Sha256HeaderID (2 bytes)
// - Data size (2 bytes)
// - Data block:
// - Signature, equals to Sha256HeaderSignature (2 bytes)
// - Data, SHA checksum value
var buf []byte
buf = binary.LittleEndian.AppendUint16(buf, Sha256HeaderID)
buf = binary.LittleEndian.AppendUint16(buf, uint16(len(checksum)+2))
buf = binary.LittleEndian.AppendUint16(buf, Sha256HeaderSignature)
buf = append(buf, checksum...)
ze.fh.Extra = append(ze.fh.Extra, buf...)
}
func (z *ZipWriter) compressPartialFile(r io.Reader, dict []byte, last bool, resultChan chan io.Reader, wg *sync.WaitGroup) {
@@ -894,17 +944,9 @@ func (z *ZipWriter) compressBlock(r io.Reader, dict []byte, last bool) (*bytes.B
}
func (z *ZipWriter) compressWholeFile(ze *zipEntry, r io.ReadSeeker, compressChan chan *zipEntry) {
z.checksumFile(r, ze)
crc := crc32.NewIEEE()
_, err := io.Copy(crc, r)
if err != nil {
z.errors <- err
return
}
ze.fh.CRC32 = crc.Sum32()
_, err = r.Seek(0, 0)
_, err := r.Seek(0, 0)
if err != nil {
z.errors <- err
return

View File

@@ -16,6 +16,7 @@ package zip
import (
"bytes"
"encoding/hex"
"hash/crc32"
"io"
"os"
@@ -35,6 +36,10 @@ var (
fileEmpty = []byte("")
fileManifest = []byte("Manifest-Version: 1.0\nCreated-By: soong_zip\n\n")
sha256FileA = "d53eda7a637c99cc7fb566d96e9fa109bf15c478410a3f5eb4d4c4e26cd081f6"
sha256FileB = "430c56c5818e62bcb6d478901ef86284e97714c138f3c86aa14fd6a84b7ce5d3"
sha256FileC = "31c5ab6111f1d6aa13c2c4e92bb3c0f7c76b61b42d141af1e846eb7f6586a51c"
fileCustomManifest = []byte("Custom manifest: true\n")
customManifestAfter = []byte("Manifest-Version: 1.0\nCreated-By: soong_zip\nCustom manifest: true\n\n")
)
@@ -67,6 +72,20 @@ func fh(name string, contents []byte, method uint16) zip.FileHeader {
}
}
func fhWithSHA256(name string, contents []byte, method uint16, sha256 string) zip.FileHeader {
h := fh(name, contents, method)
// The extra field contains 38 bytes, including 2 bytes of header ID, 2 bytes
// of size, 2 bytes of signature, and 32 bytes of checksum data block.
var extra [38]byte
// The first 6 bytes contains Sha256HeaderID (0x4967), size (unit(34)) and
// Sha256HeaderSignature (0x9514)
copy(extra[0:], []byte{103, 73, 34, 0, 20, 149})
sha256Bytes, _ := hex.DecodeString(sha256)
copy(extra[6:], sha256Bytes)
h.Extra = append(h.Extra, extra[:]...)
return h
}
func fhManifest(contents []byte) zip.FileHeader {
return zip.FileHeader{
Name: "META-INF/MANIFEST.MF",
@@ -87,13 +106,18 @@ func fhLink(name string, to string) zip.FileHeader {
}
}
func fhDir(name string) zip.FileHeader {
type fhDirOptions struct {
extra []byte
}
func fhDir(name string, opts fhDirOptions) zip.FileHeader {
return zip.FileHeader{
Name: name,
Method: zip.Store,
CRC32: crc32.ChecksumIEEE(nil),
UncompressedSize64: 0,
ExternalAttrs: (syscall.S_IFDIR|0755)<<16 | 0x10,
Extra: opts.extra,
}
}
@@ -114,6 +138,7 @@ func TestZip(t *testing.T) {
manifest string
storeSymlinks bool
ignoreMissingFiles bool
sha256Checksum bool
files []zip.FileHeader
err error
@@ -320,10 +345,10 @@ func TestZip(t *testing.T) {
emulateJar: true,
files: []zip.FileHeader{
fhDir("META-INF/"),
fhDir("META-INF/", fhDirOptions{extra: []byte{254, 202, 0, 0}}),
fhManifest(fileManifest),
fhDir("a/"),
fhDir("a/a/"),
fhDir("a/", fhDirOptions{}),
fhDir("a/a/", fhDirOptions{}),
fh("a/a/a", fileA, zip.Deflate),
fh("a/a/b", fileB, zip.Deflate),
},
@@ -338,10 +363,10 @@ func TestZip(t *testing.T) {
manifest: "manifest.txt",
files: []zip.FileHeader{
fhDir("META-INF/"),
fhDir("META-INF/", fhDirOptions{extra: []byte{254, 202, 0, 0}}),
fhManifest(customManifestAfter),
fhDir("a/"),
fhDir("a/a/"),
fhDir("a/", fhDirOptions{}),
fhDir("a/a/", fhDirOptions{}),
fh("a/a/a", fileA, zip.Deflate),
fh("a/a/b", fileB, zip.Deflate),
},
@@ -355,8 +380,8 @@ func TestZip(t *testing.T) {
dirEntries: true,
files: []zip.FileHeader{
fhDir("a/"),
fhDir("a/a/"),
fhDir("a/", fhDirOptions{}),
fhDir("a/a/", fhDirOptions{}),
fh("a/a/a", fileA, zip.Deflate),
fh("a/a/b", fileB, zip.Deflate),
},
@@ -412,6 +437,23 @@ func TestZip(t *testing.T) {
fh("a/a/a", fileA, zip.Deflate),
},
},
{
name: "generate SHA256 checksum",
args: fileArgsBuilder().
File("a/a/a").
File("a/a/b").
File("a/a/c").
File("c"),
compressionLevel: 9,
sha256Checksum: true,
files: []zip.FileHeader{
fhWithSHA256("a/a/a", fileA, zip.Deflate, sha256FileA),
fhWithSHA256("a/a/b", fileB, zip.Deflate, sha256FileB),
fhWithSHA256("a/a/c", fileC, zip.Deflate, sha256FileC),
fhWithSHA256("c", fileC, zip.Deflate, sha256FileC),
},
},
// errors
{
@@ -465,6 +507,7 @@ func TestZip(t *testing.T) {
args.ManifestSourcePath = test.manifest
args.StoreSymlinks = test.storeSymlinks
args.IgnoreMissingFiles = test.ignoreMissingFiles
args.Sha256Checksum = test.sha256Checksum
args.Filesystem = mockFs
args.Stderr = &bytes.Buffer{}
@@ -555,6 +598,11 @@ func TestZip(t *testing.T) {
t.Errorf("incorrect file %s method want %v got %v", want.Name,
want.Method, got.Method)
}
if !bytes.Equal(want.Extra, got.Extra) {
t.Errorf("incorrect file %s extra want %v got %v", want.Name,
want.Extra, got.Extra)
}
}
})
}