From 12892e8c234f4fe6f6803f052061de9057903bb2 Mon Sep 17 00:00:00 2001 From: ValarDragon Date: Wed, 28 Mar 2018 18:19:55 -0500 Subject: [PATCH] blake2b,blake2s: implement BinaryMarshaler, BinaryUnmarshaler The marshal method allows the hash's internal state to be serialized and unmarshaled at a later time, without having the re-write the entire stream of data that was already written to the hash. Fixes golang/go#24548 Change-Id: I82358c34181fc815f85d5d1509fb2fe0e62e40bd Reviewed-on: https://go-review.googlesource.com/103241 Reviewed-by: Filippo Valsorda Run-TryBot: Filippo Valsorda --- blake2b/blake2b.go | 68 +++++++++++++++++++++++++++++++++++++++++ blake2b/blake2b_test.go | 49 +++++++++++++++++++++++++++++ blake2s/blake2s.go | 57 ++++++++++++++++++++++++++++++++++ blake2s/blake2s_test.go | 48 +++++++++++++++++++++++++++++ 4 files changed, 222 insertions(+) diff --git a/blake2b/blake2b.go b/blake2b/blake2b.go index 6dedb89467..58ea875361 100644 --- a/blake2b/blake2b.go +++ b/blake2b/blake2b.go @@ -92,6 +92,8 @@ func New256(key []byte) (hash.Hash, error) { return newDigest(Size256, key) } // values equal or greater than: // - 32 if BLAKE2b is used as a hash function (The key is zero bytes long). // - 16 if BLAKE2b is used as a MAC function (The key is at least 16 bytes long). +// When the key is nil, the returned hash.Hash implements BinaryMarshaler +// and BinaryUnmarshaler for state (de)serialization as documented by hash.Hash. func New(size int, key []byte) (hash.Hash, error) { return newDigest(size, key) } func newDigest(hashSize int, key []byte) (*digest, error) { @@ -150,6 +152,50 @@ type digest struct { keyLen int } +const ( + magic = "b2b" + marshaledSize = len(magic) + 8*8 + 2*8 + 1 + BlockSize + 1 +) + +func (d *digest) MarshalBinary() ([]byte, error) { + if d.keyLen != 0 { + return nil, errors.New("crypto/blake2b: cannot marshal MACs") + } + b := make([]byte, 0, marshaledSize) + b = append(b, magic...) + for i := 0; i < 8; i++ { + b = appendUint64(b, d.h[i]) + } + b = appendUint64(b, d.c[0]) + b = appendUint64(b, d.c[1]) + // Maximum value for size is 64 + b = append(b, byte(d.size)) + b = append(b, d.block[:]...) + b = append(b, byte(d.offset)) + return b, nil +} + +func (d *digest) UnmarshalBinary(b []byte) error { + if len(b) < len(magic) || string(b[:len(magic)]) != magic { + return errors.New("crypto/blake2b: invalid hash state identifier") + } + if len(b) != marshaledSize { + return errors.New("crypto/blake2b: invalid hash state size") + } + b = b[len(magic):] + for i := 0; i < 8; i++ { + b, d.h[i] = consumeUint64(b) + } + b, d.c[0] = consumeUint64(b) + b, d.c[1] = consumeUint64(b) + d.size = int(b[0]) + b = b[1:] + copy(d.block[:], b[:BlockSize]) + b = b[BlockSize:] + d.offset = int(b[0]) + return nil +} + func (d *digest) BlockSize() int { return BlockSize } func (d *digest) Size() int { return d.size } @@ -219,3 +265,25 @@ func (d *digest) finalize(hash *[Size]byte) { binary.LittleEndian.PutUint64(hash[8*i:], v) } } + +func appendUint64(b []byte, x uint64) []byte { + var a [8]byte + binary.BigEndian.PutUint64(a[:], x) + return append(b, a[:]...) +} + +func appendUint32(b []byte, x uint32) []byte { + var a [4]byte + binary.BigEndian.PutUint32(a[:], x) + return append(b, a[:]...) +} + +func consumeUint64(b []byte) ([]byte, uint64) { + x := binary.BigEndian.Uint64(b) + return b[8:], x +} + +func consumeUint32(b []byte) ([]byte, uint32) { + x := binary.BigEndian.Uint32(b) + return b[4:], x +} diff --git a/blake2b/blake2b_test.go b/blake2b/blake2b_test.go index 5d68bbf604..723327ab56 100644 --- a/blake2b/blake2b_test.go +++ b/blake2b/blake2b_test.go @@ -6,6 +6,7 @@ package blake2b import ( "bytes" + "encoding" "encoding/hex" "fmt" "hash" @@ -69,6 +70,54 @@ func TestHashes2X(t *testing.T) { testHashes2X(t) } +func TestMarshal(t *testing.T) { + input := make([]byte, 255) + for i := range input { + input[i] = byte(i) + } + for _, size := range []int{Size, Size256, Size384, 12, 25, 63} { + for i := 0; i < 256; i++ { + h, err := New(size, nil) + if err != nil { + t.Fatalf("size=%d, len(input)=%d: error from New(%v, nil): %v", size, i, size, err) + } + h2, err := New(size, nil) + if err != nil { + t.Fatalf("size=%d, len(input)=%d: error from New(%v, nil): %v", size, i, size, err) + } + + h.Write(input[:i/2]) + halfstate, err := h.(encoding.BinaryMarshaler).MarshalBinary() + if err != nil { + t.Fatalf("size=%d, len(input)=%d: could not marshal: %v", size, i, err) + } + err = h2.(encoding.BinaryUnmarshaler).UnmarshalBinary(halfstate) + if err != nil { + t.Fatalf("size=%d, len(input)=%d: could not unmarshal: %v", size, i, err) + } + + h.Write(input[i/2 : i]) + sum := h.Sum(nil) + h2.Write(input[i/2 : i]) + sum2 := h2.Sum(nil) + + if !bytes.Equal(sum, sum2) { + t.Fatalf("size=%d, len(input)=%d: results do not match; sum = %v, sum2 = %v", size, i, sum, sum2) + } + + h3, err := New(size, nil) + if err != nil { + t.Fatalf("size=%d, len(input)=%d: error from New(%v, nil): %v", size, i, size, err) + } + h3.Write(input[:i]) + sum3 := h3.Sum(nil) + if !bytes.Equal(sum, sum3) { + t.Fatalf("size=%d, len(input)=%d: sum = %v, want %v", size, i, sum, sum3) + } + } + } +} + func testHashes(t *testing.T) { key, _ := hex.DecodeString("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f") diff --git a/blake2s/blake2s.go b/blake2s/blake2s.go index ae0dc922b9..5fb4a9ecd1 100644 --- a/blake2s/blake2s.go +++ b/blake2s/blake2s.go @@ -49,6 +49,8 @@ func Sum256(data []byte) [Size]byte { // New256 returns a new hash.Hash computing the BLAKE2s-256 checksum. A non-nil // key turns the hash into a MAC. The key must between zero and 32 bytes long. +// When the key is nil, the returned hash.Hash implements BinaryMarshaler +// and BinaryUnmarshaler for state (de)serialization as documented by hash.Hash. func New256(key []byte) (hash.Hash, error) { return newDigest(Size, key) } // New128 returns a new hash.Hash computing the BLAKE2s-128 checksum given a @@ -120,6 +122,50 @@ type digest struct { keyLen int } +const ( + magic = "b2s" + marshaledSize = len(magic) + 8*4 + 2*4 + 1 + BlockSize + 1 +) + +func (d *digest) MarshalBinary() ([]byte, error) { + if d.keyLen != 0 { + return nil, errors.New("crypto/blake2s: cannot marshal MACs") + } + b := make([]byte, 0, marshaledSize) + b = append(b, magic...) + for i := 0; i < 8; i++ { + b = appendUint32(b, d.h[i]) + } + b = appendUint32(b, d.c[0]) + b = appendUint32(b, d.c[1]) + // Maximum value for size is 32 + b = append(b, byte(d.size)) + b = append(b, d.block[:]...) + b = append(b, byte(d.offset)) + return b, nil +} + +func (d *digest) UnmarshalBinary(b []byte) error { + if len(b) < len(magic) || string(b[:len(magic)]) != magic { + return errors.New("crypto/blake2s: invalid hash state identifier") + } + if len(b) != marshaledSize { + return errors.New("crypto/blake2s: invalid hash state size") + } + b = b[len(magic):] + for i := 0; i < 8; i++ { + b, d.h[i] = consumeUint32(b) + } + b, d.c[0] = consumeUint32(b) + b, d.c[1] = consumeUint32(b) + d.size = int(b[0]) + b = b[1:] + copy(d.block[:], b[:BlockSize]) + b = b[BlockSize:] + d.offset = int(b[0]) + return nil +} + func (d *digest) BlockSize() int { return BlockSize } func (d *digest) Size() int { return d.size } @@ -185,3 +231,14 @@ func (d *digest) finalize(hash *[Size]byte) { binary.LittleEndian.PutUint32(hash[4*i:], v) } } + +func appendUint32(b []byte, x uint32) []byte { + var a [4]byte + binary.BigEndian.PutUint32(a[:], x) + return append(b, a[:]...) +} + +func consumeUint32(b []byte) ([]byte, uint32) { + x := binary.BigEndian.Uint32(b) + return b[4:], x +} diff --git a/blake2s/blake2s_test.go b/blake2s/blake2s_test.go index cfeb18bb43..cde79fb1cd 100644 --- a/blake2s/blake2s_test.go +++ b/blake2s/blake2s_test.go @@ -5,6 +5,8 @@ package blake2s import ( + "bytes" + "encoding" "encoding/hex" "fmt" "testing" @@ -64,6 +66,52 @@ func TestHashes2X(t *testing.T) { testHashes2X(t) } +func TestMarshal(t *testing.T) { + input := make([]byte, 255) + for i := range input { + input[i] = byte(i) + } + for i := 0; i < 256; i++ { + h, err := New256(nil) + if err != nil { + t.Fatalf("len(input)=%d: error from New256(nil): %v", i, err) + } + h2, err := New256(nil) + if err != nil { + t.Fatalf("len(input)=%d: error from New256(nil): %v", i, err) + } + + h.Write(input[:i/2]) + halfstate, err := h.(encoding.BinaryMarshaler).MarshalBinary() + if err != nil { + t.Fatalf("len(input)=%d: could not marshal: %v", i, err) + } + err = h2.(encoding.BinaryUnmarshaler).UnmarshalBinary(halfstate) + if err != nil { + t.Fatalf("len(input)=%d: could not unmarshal: %v", i, err) + } + + h.Write(input[i/2 : i]) + sum := h.Sum(nil) + h2.Write(input[i/2 : i]) + sum2 := h2.Sum(nil) + + if !bytes.Equal(sum, sum2) { + t.Fatalf("len(input)=%d: results do not match; sum = %v, sum2 = %v", i, sum, sum2) + } + + h3, err := New256(nil) + if err != nil { + t.Fatalf("len(input)=%d: error from New256(nil): %v", i, err) + } + h3.Write(input[:i]) + sum3 := h3.Sum(nil) + if !bytes.Equal(sum, sum3) { + t.Fatalf("len(input)=%d: sum = %v, want %v", i, sum, sum3) + } + } +} + func testHashes(t *testing.T) { key, _ := hex.DecodeString("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f")