| 'use strict'; |
| |
| var utils = require('../utils'); |
| var common = require('../common'); |
| var shaCommon = require('./common'); |
| var assert = require('minimalistic-assert'); |
| |
| var sum32 = utils.sum32; |
| var sum32_4 = utils.sum32_4; |
| var sum32_5 = utils.sum32_5; |
| var ch32 = shaCommon.ch32; |
| var maj32 = shaCommon.maj32; |
| var s0_256 = shaCommon.s0_256; |
| var s1_256 = shaCommon.s1_256; |
| var g0_256 = shaCommon.g0_256; |
| var g1_256 = shaCommon.g1_256; |
| |
| var BlockHash = common.BlockHash; |
| |
| var sha256_K = [ |
| 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 |
| ]; |
| |
| function SHA256() { |
| if (!(this instanceof SHA256)) |
| return new SHA256(); |
| |
| BlockHash.call(this); |
| this.h = [ |
| 0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, |
| 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19 |
| ]; |
| this.k = sha256_K; |
| this.W = new Array(64); |
| } |
| utils.inherits(SHA256, BlockHash); |
| module.exports = SHA256; |
| |
| SHA256.blockSize = 512; |
| SHA256.outSize = 256; |
| SHA256.hmacStrength = 192; |
| SHA256.padLength = 64; |
| |
| SHA256.prototype._update = function _update(msg, start) { |
| var W = this.W; |
| |
| for (var i = 0; i < 16; i++) |
| W[i] = msg[start + i]; |
| for (; i < W.length; i++) |
| W[i] = sum32_4(g1_256(W[i - 2]), W[i - 7], g0_256(W[i - 15]), W[i - 16]); |
| |
| var a = this.h[0]; |
| var b = this.h[1]; |
| var c = this.h[2]; |
| var d = this.h[3]; |
| var e = this.h[4]; |
| var f = this.h[5]; |
| var g = this.h[6]; |
| var h = this.h[7]; |
| |
| assert(this.k.length === W.length); |
| for (i = 0; i < W.length; i++) { |
| var T1 = sum32_5(h, s1_256(e), ch32(e, f, g), this.k[i], W[i]); |
| var T2 = sum32(s0_256(a), maj32(a, b, c)); |
| h = g; |
| g = f; |
| f = e; |
| e = sum32(d, T1); |
| d = c; |
| c = b; |
| b = a; |
| a = sum32(T1, T2); |
| } |
| |
| this.h[0] = sum32(this.h[0], a); |
| this.h[1] = sum32(this.h[1], b); |
| this.h[2] = sum32(this.h[2], c); |
| this.h[3] = sum32(this.h[3], d); |
| this.h[4] = sum32(this.h[4], e); |
| this.h[5] = sum32(this.h[5], f); |
| this.h[6] = sum32(this.h[6], g); |
| this.h[7] = sum32(this.h[7], h); |
| }; |
| |
| SHA256.prototype._digest = function digest(enc) { |
| if (enc === 'hex') |
| return utils.toHex32(this.h, 'big'); |
| else |
| return utils.split32(this.h, 'big'); |
| }; |