cryptojs.sha256.js

/*!
* Crypto-JS v2.5.4	SHA256.js
* http://code.google.com/p/crypto-js/
* Copyright (c) 2009-2013, Jeff Mott. All rights reserved.
* http://code.google.com/p/crypto-js/wiki/License
*/
(function () {

	// Shortcuts
	var C = Crypto,
		util = C.util,
		charenc = C.charenc,
		UTF8 = charenc.UTF8,
		Binary = charenc.Binary;

	// Constants
	var 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];

	// Public API
	var SHA256 = C.SHA256 = function (message, options) {
		var digestbytes = util.wordsToBytes(SHA256._sha256(message));
		return options && options.asBytes ? digestbytes :
	    options && options.asString ? Binary.bytesToString(digestbytes) :
	    util.bytesToHex(digestbytes);
	};

	// The core
	SHA256._sha256 = function (message) {

		// Convert to byte array
		if (message.constructor == String) message = UTF8.stringToBytes(message);
		/* else, assume byte array already */

		var m = util.bytesToWords(message),
		l = message.length * 8,
		H = [0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A,
				0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19],
		w = [],
		a, b, c, d, e, f, g, h, i, j,
		t1, t2;

		// Padding
		m[l >> 5] |= 0x80 << (24 - l % 32);
		m[((l + 64 >> 9) << 4) + 15] = l;

		for (var i = 0; i < m.length; i += 16) {

			a = H[0];
			b = H[1];
			c = H[2];
			d = H[3];
			e = H[4];
			f = H[5];
			g = H[6];
			h = H[7];

			for (var j = 0; j < 64; j++) {

				if (j < 16) w[j] = m[j + i];
				else {

					var gamma0x = w[j - 15],
				gamma1x = w[j - 2],
				gamma0 = ((gamma0x << 25) | (gamma0x >>> 7)) ^
				            ((gamma0x << 14) | (gamma0x >>> 18)) ^
				            (gamma0x >>> 3),
				gamma1 = ((gamma1x << 15) | (gamma1x >>> 17)) ^
				            ((gamma1x << 13) | (gamma1x >>> 19)) ^
				            (gamma1x >>> 10);

					w[j] = gamma0 + (w[j - 7] >>> 0) +
				    gamma1 + (w[j - 16] >>> 0);

				}

				var ch = e & f ^ ~e & g,
			maj = a & b ^ a & c ^ b & c,
			sigma0 = ((a << 30) | (a >>> 2)) ^
			            ((a << 19) | (a >>> 13)) ^
			            ((a << 10) | (a >>> 22)),
			sigma1 = ((e << 26) | (e >>> 6)) ^
			            ((e << 21) | (e >>> 11)) ^
			            ((e << 7) | (e >>> 25));


				t1 = (h >>> 0) + sigma1 + ch + (K[j]) + (w[j] >>> 0);
				t2 = sigma0 + maj;

				h = g;
				g = f;
				f = e;
				e = (d + t1) >>> 0;
				d = c;
				c = b;
				b = a;
				a = (t1 + t2) >>> 0;

			}

			H[0] += a;
			H[1] += b;
			H[2] += c;
			H[3] += d;
			H[4] += e;
			H[5] += f;
			H[6] += g;
			H[7] += h;

		}

		return H;

	};

	// Package private blocksize
	SHA256._blocksize = 16;

	SHA256._digestsize = 32;

})();