| // 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. |
| |
| // SHA256 block step. |
| // In its own file so that a faster assembly or C version |
| // can be substituted easily. |
| |
| package sha256 |
| |
| var _K = []uint32{ |
| 0x428a2f98, |
| 0x71374491, |
| 0xb5c0fbcf, |
| 0xe9b5dba5, |
| 0x3956c25b, |
| 0x59f111f1, |
| 0x923f82a4, |
| 0xab1c5ed5, |
| 0xd807aa98, |
| 0x12835b01, |
| 0x243185be, |
| 0x550c7dc3, |
| 0x72be5d74, |
| 0x80deb1fe, |
| 0x9bdc06a7, |
| 0xc19bf174, |
| 0xe49b69c1, |
| 0xefbe4786, |
| 0x0fc19dc6, |
| 0x240ca1cc, |
| 0x2de92c6f, |
| 0x4a7484aa, |
| 0x5cb0a9dc, |
| 0x76f988da, |
| 0x983e5152, |
| 0xa831c66d, |
| 0xb00327c8, |
| 0xbf597fc7, |
| 0xc6e00bf3, |
| 0xd5a79147, |
| 0x06ca6351, |
| 0x14292967, |
| 0x27b70a85, |
| 0x2e1b2138, |
| 0x4d2c6dfc, |
| 0x53380d13, |
| 0x650a7354, |
| 0x766a0abb, |
| 0x81c2c92e, |
| 0x92722c85, |
| 0xa2bfe8a1, |
| 0xa81a664b, |
| 0xc24b8b70, |
| 0xc76c51a3, |
| 0xd192e819, |
| 0xd6990624, |
| 0xf40e3585, |
| 0x106aa070, |
| 0x19a4c116, |
| 0x1e376c08, |
| 0x2748774c, |
| 0x34b0bcb5, |
| 0x391c0cb3, |
| 0x4ed8aa4a, |
| 0x5b9cca4f, |
| 0x682e6ff3, |
| 0x748f82ee, |
| 0x78a5636f, |
| 0x84c87814, |
| 0x8cc70208, |
| 0x90befffa, |
| 0xa4506ceb, |
| 0xbef9a3f7, |
| 0xc67178f2, |
| } |
| |
| func _Block(dig *digest, p []byte) int { |
| var w [64]uint32 |
| n := 0 |
| h0, h1, h2, h3, h4, h5, h6, h7 := dig.h[0], dig.h[1], dig.h[2], dig.h[3], dig.h[4], dig.h[5], dig.h[6], dig.h[7] |
| for len(p) >= _Chunk { |
| // Can interlace the computation of w with the |
| // rounds below if needed for speed. |
| for i := 0; i < 16; i++ { |
| j := i * 4 |
| w[i] = uint32(p[j])<<24 | uint32(p[j+1])<<16 | uint32(p[j+2])<<8 | uint32(p[j+3]) |
| } |
| for i := 16; i < 64; i++ { |
| t1 := (w[i-2]>>17 | w[i-2]<<(32-17)) ^ (w[i-2]>>19 | w[i-2]<<(32-19)) ^ (w[i-2] >> 10) |
| |
| t2 := (w[i-15]>>7 | w[i-15]<<(32-7)) ^ (w[i-15]>>18 | w[i-15]<<(32-18)) ^ (w[i-15] >> 3) |
| |
| w[i] = t1 + w[i-7] + t2 + w[i-16] |
| } |
| |
| a, b, c, d, e, f, g, h := h0, h1, h2, h3, h4, h5, h6, h7 |
| |
| for i := 0; i < 64; i++ { |
| t1 := h + ((e>>6 | e<<(32-6)) ^ (e>>11 | e<<(32-11)) ^ (e>>25 | e<<(32-25))) + ((e & f) ^ (^e & g)) + _K[i] + w[i] |
| |
| t2 := ((a>>2 | a<<(32-2)) ^ (a>>13 | a<<(32-13)) ^ (a>>22 | a<<(32-22))) + ((a & b) ^ (a & c) ^ (b & c)) |
| |
| h = g |
| g = f |
| f = e |
| e = d + t1 |
| d = c |
| c = b |
| b = a |
| a = t1 + t2 |
| } |
| |
| h0 += a |
| h1 += b |
| h2 += c |
| h3 += d |
| h4 += e |
| h5 += f |
| h6 += g |
| h7 += h |
| |
| p = p[_Chunk:] |
| n += _Chunk |
| } |
| |
| dig.h[0], dig.h[1], dig.h[2], dig.h[3], dig.h[4], dig.h[5], dig.h[6], dig.h[7] = h0, h1, h2, h3, h4, h5, h6, h7 |
| return n |
| } |