diff options
Diffstat (limited to 'src/crypto/sha512/sha512.go')
-rw-r--r-- | src/crypto/sha512/sha512.go | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/src/crypto/sha512/sha512.go b/src/crypto/sha512/sha512.go new file mode 100644 index 000000000..bca7a91e2 --- /dev/null +++ b/src/crypto/sha512/sha512.go @@ -0,0 +1,198 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package sha512 implements the SHA384 and SHA512 hash algorithms as defined +// in FIPS 180-2. +package sha512 + +import ( + "crypto" + "hash" +) + +func init() { + crypto.RegisterHash(crypto.SHA384, New384) + crypto.RegisterHash(crypto.SHA512, New) +} + +// The size of a SHA512 checksum in bytes. +const Size = 64 + +// The size of a SHA384 checksum in bytes. +const Size384 = 48 + +// The blocksize of SHA512 and SHA384 in bytes. +const BlockSize = 128 + +const ( + chunk = 128 + init0 = 0x6a09e667f3bcc908 + init1 = 0xbb67ae8584caa73b + init2 = 0x3c6ef372fe94f82b + init3 = 0xa54ff53a5f1d36f1 + init4 = 0x510e527fade682d1 + init5 = 0x9b05688c2b3e6c1f + init6 = 0x1f83d9abfb41bd6b + init7 = 0x5be0cd19137e2179 + init0_384 = 0xcbbb9d5dc1059ed8 + init1_384 = 0x629a292a367cd507 + init2_384 = 0x9159015a3070dd17 + init3_384 = 0x152fecd8f70e5939 + init4_384 = 0x67332667ffc00b31 + init5_384 = 0x8eb44a8768581511 + init6_384 = 0xdb0c2e0d64f98fa7 + init7_384 = 0x47b5481dbefa4fa4 +) + +// digest represents the partial evaluation of a checksum. +type digest struct { + h [8]uint64 + x [chunk]byte + nx int + len uint64 + is384 bool // mark if this digest is SHA-384 +} + +func (d *digest) Reset() { + if !d.is384 { + d.h[0] = init0 + d.h[1] = init1 + d.h[2] = init2 + d.h[3] = init3 + d.h[4] = init4 + d.h[5] = init5 + d.h[6] = init6 + d.h[7] = init7 + } else { + d.h[0] = init0_384 + d.h[1] = init1_384 + d.h[2] = init2_384 + d.h[3] = init3_384 + d.h[4] = init4_384 + d.h[5] = init5_384 + d.h[6] = init6_384 + d.h[7] = init7_384 + } + d.nx = 0 + d.len = 0 +} + +// New returns a new hash.Hash computing the SHA512 checksum. +func New() hash.Hash { + d := new(digest) + d.Reset() + return d +} + +// New384 returns a new hash.Hash computing the SHA384 checksum. +func New384() hash.Hash { + d := new(digest) + d.is384 = true + d.Reset() + return d +} + +func (d *digest) Size() int { + if !d.is384 { + return Size + } + return Size384 +} + +func (d *digest) BlockSize() int { return BlockSize } + +func (d *digest) Write(p []byte) (nn int, err error) { + nn = len(p) + d.len += uint64(nn) + if d.nx > 0 { + n := copy(d.x[d.nx:], p) + d.nx += n + if d.nx == chunk { + block(d, d.x[:]) + d.nx = 0 + } + p = p[n:] + } + if len(p) >= chunk { + n := len(p) &^ (chunk - 1) + block(d, p[:n]) + p = p[n:] + } + if len(p) > 0 { + d.nx = copy(d.x[:], p) + } + return +} + +func (d0 *digest) Sum(in []byte) []byte { + // Make a copy of d0 so that caller can keep writing and summing. + d := new(digest) + *d = *d0 + hash := d.checkSum() + if d.is384 { + return append(in, hash[:Size384]...) + } + return append(in, hash[:]...) +} + +func (d *digest) checkSum() [Size]byte { + // Padding. Add a 1 bit and 0 bits until 112 bytes mod 128. + len := d.len + var tmp [128]byte + tmp[0] = 0x80 + if len%128 < 112 { + d.Write(tmp[0 : 112-len%128]) + } else { + d.Write(tmp[0 : 128+112-len%128]) + } + + // Length in bits. + len <<= 3 + for i := uint(0); i < 16; i++ { + tmp[i] = byte(len >> (120 - 8*i)) + } + d.Write(tmp[0:16]) + + if d.nx != 0 { + panic("d.nx != 0") + } + + h := d.h[:] + if d.is384 { + h = d.h[:6] + } + + var digest [Size]byte + for i, s := range h { + digest[i*8] = byte(s >> 56) + digest[i*8+1] = byte(s >> 48) + digest[i*8+2] = byte(s >> 40) + digest[i*8+3] = byte(s >> 32) + digest[i*8+4] = byte(s >> 24) + digest[i*8+5] = byte(s >> 16) + digest[i*8+6] = byte(s >> 8) + digest[i*8+7] = byte(s) + } + + return digest +} + +// Sum512 returns the SHA512 checksum of the data. +func Sum512(data []byte) [Size]byte { + var d digest + d.Reset() + d.Write(data) + return d.checkSum() +} + +// Sum384 returns the SHA384 checksum of the data. +func Sum384(data []byte) (sum384 [Size384]byte) { + var d digest + d.is384 = true + d.Reset() + d.Write(data) + sum := d.checkSum() + copy(sum384[:], sum[:Size384]) + return +} |