Snapshot sync: use hasher for chunk hashes (#7215) (#7259)

* snapshot sync: use blake3 for chunk hashes (7215)

Blake3 improves on security and speed compared to sha256.
https://blake3.io/

In this PR:
+ use optimized blake3 hashes (with dedicated SIMD code)
  instead of sha256
+ reuse resources on hashing chunks.
+ cleaned few error return statements.

* linter issues fixes

* revert blake2 hashing to sha256

* revert go.mod

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

snapshots/helpers_test.go

@@ -16,15 +16,13 @@ import (
 	"github.com/cosmos/cosmos-sdk/snapshots/types"
 )
 
-func checksum(b []byte) []byte {
-	hash := sha256.Sum256(b)
-	return hash[:]
-}
-
 func checksums(slice [][]byte) [][]byte {
-	checksums := [][]byte{}
-	for _, chunk := range slice {
-		checksums = append(checksums, checksum(chunk))
+	hasher := sha256.New()
+	checksums := make([][]byte, len(slice))
+	for i, chunk := range slice {
+		hasher.Write(chunk)
+		checksums[i] = hasher.Sum(nil)
+		hasher.Reset()
 	}
 	return checksums
 }

snapshots/manager_test.go

@@ -79,11 +79,8 @@ func TestManager_Take(t *testing.T) {
 		Chunks: 3,
 		Hash:   []uint8{0x47, 0xe4, 0xee, 0x7f, 0x21, 0x1f, 0x73, 0x26, 0x5d, 0xd1, 0x76, 0x58, 0xf6, 0xe2, 0x1c, 0x13, 0x18, 0xbd, 0x6c, 0x81, 0xf3, 0x75, 0x98, 0xe2, 0xa, 0x27, 0x56, 0x29, 0x95, 0x42, 0xef, 0xcf},
 		Metadata: types.Metadata{
-			ChunkHashes: [][]byte{
-				checksum([]byte{1, 2, 3}),
-				checksum([]byte{4, 5, 6}),
-				checksum([]byte{7, 8, 9}),
-			},
+			ChunkHashes: checksums([][]byte{
+				{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}),
 		},
 	}, snapshot)
 

snapshots/store.go

@@ -63,11 +63,8 @@ func (s *Store) Delete(height uint64, format uint32) error {
 			height, format)
 	}
 	err = os.RemoveAll(s.pathSnapshot(height, format))
-	if err != nil {
-		return sdkerrors.Wrapf(err, "failed to delete snapshot chunks for height %v format %v",
-			height, format)
-	}
-	return nil
+	return sdkerrors.Wrapf(err, "failed to delete snapshot chunks for height %v format %v",
+		height, format)
 }
 
 // Get fetches snapshot info from the database.
@@ -109,10 +106,7 @@ func (s *Store) GetLatest() (*types.Snapshot, error) {
 		}
 	}
 	err = iter.Error()
-	if err != nil {
-		return nil, sdkerrors.Wrap(err, "failed to find latest snapshot")
-	}
-	return snapshot, nil
+	return snapshot, sdkerrors.Wrap(err, "failed to find latest snapshot")
 }
 
 // List lists snapshots, in reverse order (newest first).
@@ -132,23 +126,16 @@ func (s *Store) List() ([]*types.Snapshot, error) {
 		}
 		snapshots = append(snapshots, snapshot)
 	}
-	err = iter.Error()
-	if err != nil {
-		return nil, err
-	}
-	return snapshots, nil
+	return snapshots, iter.Error()
 }
 
 // Load loads a snapshot (both metadata and binary chunks). The chunks must be consumed and closed.
 // Returns nil if the snapshot does not exist.
 func (s *Store) Load(height uint64, format uint32) (*types.Snapshot, <-chan io.ReadCloser, error) {
 	snapshot, err := s.Get(height, format)
-	if err != nil {
+	if snapshot == nil || err != nil {
 		return nil, nil, err
 	}
-	if snapshot == nil {
-		return nil, nil, nil
-	}
 
 	ch := make(chan io.ReadCloser)
 	go func() {
@@ -189,11 +176,7 @@ func (s *Store) LoadChunk(height uint64, format uint32, chunk uint32) (io.ReadCl
 // loadChunkFile loads a chunk from disk, and errors if it does not exist.
 func (s *Store) loadChunkFile(height uint64, format uint32, chunk uint32) (io.ReadCloser, error) {
 	path := s.pathChunk(height, format, chunk)
-	file, err := os.Open(path)
-	if err != nil {
-		return nil, err
-	}
-	return file, nil
+	return os.Open(path)
 }
 
 // Prune removes old snapshots. The given number of most recent heights (regardless of format) are retained.
@@ -233,11 +216,7 @@ func (s *Store) Prune(retain uint32) (uint64, error) {
 			}
 		}
 	}
-	err = iter.Error()
-	if err != nil {
-		return 0, err
-	}
-	return pruned, nil
+	return pruned, iter.Error()
 }
 
 // Save saves a snapshot to disk, returning it.
@@ -292,6 +271,7 @@ func (s *Store) Save(
 			return nil, sdkerrors.Wrapf(err, "failed to create snapshot chunk file %q", path)
 		}
 		defer file.Close() // nolint: staticcheck
+
 		chunkHasher.Reset()
 		_, err = io.Copy(io.MultiWriter(file, chunkHasher, snapshotHasher), chunkBody)
 		if err != nil {
@@ -310,11 +290,7 @@ func (s *Store) Save(
 	}
 	snapshot.Chunks = index
 	snapshot.Hash = snapshotHasher.Sum(nil)
-	err = s.saveSnapshot(snapshot)
-	if err != nil {
-		return nil, err
-	}
-	return snapshot, nil
+	return snapshot, s.saveSnapshot(snapshot)
 }
 
 // saveSnapshot saves snapshot metadata to the database.
@@ -324,10 +300,7 @@ func (s *Store) saveSnapshot(snapshot *types.Snapshot) error {
 		return sdkerrors.Wrap(err, "failed to encode snapshot metadata")
 	}
 	err = s.db.SetSync(encodeKey(snapshot.Height, snapshot.Format), value)
-	if err != nil {
-		return sdkerrors.Wrap(err, "failed to store snapshot")
-	}
-	return nil
+	return sdkerrors.Wrap(err, "failed to store snapshot")
 }
 
 // pathHeight generates the path to a height, containing multiple snapshot formats.

snapshots/store_test.go

@@ -112,10 +112,8 @@ func TestStore_Get(t *testing.T) {
 		Chunks: 2,
 		Hash:   hash([][]byte{{2, 1, 0}, {2, 1, 1}}),
 		Metadata: types.Metadata{
-			ChunkHashes: [][]byte{
-				checksum([]byte{2, 1, 0}),
-				checksum([]byte{2, 1, 1}),
-			},
+			ChunkHashes: checksums([][]byte{
+				{2, 1, 0}, {2, 1, 1}}),
 		},
 	}, snapshot)
 }
@@ -182,10 +180,8 @@ func TestStore_Load(t *testing.T) {
 		Chunks: 2,
 		Hash:   hash([][]byte{{2, 1, 0}, {2, 1, 1}}),
 		Metadata: types.Metadata{
-			ChunkHashes: [][]byte{
-				checksum([]byte{2, 1, 0}),
-				checksum([]byte{2, 1, 1}),
-			},
+			ChunkHashes: checksums([][]byte{
+				{2, 1, 0}, {2, 1, 1}}),
 		},
 	}, snapshot)
 
@@ -275,10 +271,7 @@ func TestStore_Save(t *testing.T) {
 		Chunks: 2,
 		Hash:   hash([][]byte{{1}, {2}}),
 		Metadata: types.Metadata{
-			ChunkHashes: [][]byte{
-				checksum([]byte{1}),
-				checksum([]byte{2}),
-			},
+			ChunkHashes: checksums([][]byte{{1}, {2}}),
 		},
 	}, snapshot)
 	loaded, err := store.Get(snapshot.Height, snapshot.Format)

store/rootmulti/store_test.go

@@ -566,8 +566,9 @@ func TestMultistoreSnapshot_Checksum(t *testing.T) {
 			chunks, err := store.Snapshot(version, tc.format)
 			require.NoError(t, err)
 			hashes := []string{}
+			hasher := sha256.New()
 			for chunk := range chunks {
-				hasher := sha256.New()
+				hasher.Reset()
 				_, err := io.Copy(hasher, chunk)
 				require.NoError(t, err)
 				hashes = append(hashes, hex.EncodeToString(hasher.Sum(nil)))