MD5 method for String object

md5.js

String.prototype.md5 = function() {
	var safe_add = function(x, y) {
		var lsw = (x & 0xFFFF) + (y & 0xFFFF);
		var msw = (x >> 16) + (y >> 16) + (lsw >> 16);

		return (msw << 16) | (lsw & 0xFFFF);
	}

	var rol = function(num, cnt) {
		return (num << cnt) | (num >>> (32 - cnt));
	}

	var cmn = function(q, a, b, x, s, t) {
		return safe_add(rol(safe_add(safe_add(a, q), safe_add(x, t)), s), b);
	}

	var ff = function(a, b, c, d, x, s, t) {
		return cmn((b & c) | ((~b) & d), a, b, x, s, t);
	}

	var gg = function(a, b, c, d, x, s, t) {
		return cmn((b & d) | (c & (~d)), a, b, x, s, t);
	}

	var hh = function(a, b, c, d, x, s, t) {
		return cmn(b ^ c ^ d, a, b, x, s, t);
	}

	var ii = function(a, b, c, d, x, s, t) {
		return cmn(c ^ (b | (~d)), a, b, x, s, t);
	}

	var coreMD5 = function(x) {
		var olda, oldb, oldc, oldd, i, len=x.length;
		var a = 1732584193;
		var b = -271733879;
		var c = -1732584194;
		var d = 271733878;
		for (i=0; i<len; i+=16) {
			olda = a;
			oldb = b;
			oldc = c;
			oldd = d;

			a = ff(a, b, c, d, x[i + 0], 7, -680876936);
			d = ff(d, a, b, c, x[i + 1], 12, -389564586);
			c = ff(c, d, a, b, x[i + 2], 17, 606105819);
			b = ff(b, c, d, a, x[i + 3], 22, -1044525330);
			a = ff(a, b, c, d, x[i + 4], 7, -176418897);
			d = ff(d, a, b, c, x[i + 5], 12, 1200080426);
			c = ff(c, d, a, b, x[i + 6], 17, -1473231341);
			b = ff(b, c, d, a, x[i + 7], 22, -45705983);
			a = ff(a, b, c, d, x[i + 8], 7, 1770035416);
			d = ff(d, a, b, c, x[i + 9], 12, -1958414417);
			c = ff(c, d, a, b, x[i + 10], 17, -42063);
			b = ff(b, c, d, a, x[i + 11], 22, -1990404162);
			a = ff(a, b, c, d, x[i + 12], 7, 1804603682);
			d = ff(d, a, b, c, x[i + 13], 12, -40341101);
			c = ff(c, d, a, b, x[i + 14], 17, -1502002290);
			b = ff(b, c, d, a, x[i + 15], 22, 1236535329);
			a = gg(a, b, c, d, x[i + 1], 5, -165796510);
			d = gg(d, a, b, c, x[i + 6], 9, -1069501632);
			c = gg(c, d, a, b, x[i + 11], 14, 643717713);
			b = gg(b, c, d, a, x[i + 0], 20, -373897302);
			a = gg(a, b, c, d, x[i + 5], 5, -701558691);
			d = gg(d, a, b, c, x[i + 10], 9, 38016083);
			c = gg(c, d, a, b, x[i + 15], 14, -660478335);
			b = gg(b, c, d, a, x[i + 4], 20, -405537848);
			a = gg(a, b, c, d, x[i + 9], 5, 568446438);
			d = gg(d, a, b, c, x[i + 14], 9, -1019803690);
			c = gg(c, d, a, b, x[i + 3], 14, -187363961);
			b = gg(b, c, d, a, x[i + 8], 20, 1163531501);
			a = gg(a, b, c, d, x[i + 13], 5, -1444681467);
			d = gg(d, a, b, c, x[i + 2], 9, -51403784);
			c = gg(c, d, a, b, x[i + 7], 14, 1735328473);
			b = gg(b, c, d, a, x[i + 12], 20, -1926607734);
			a = hh(a, b, c, d, x[i + 5], 4, -378558);
			d = hh(d, a, b, c, x[i + 8], 11, -2022574463);
			c = hh(c, d, a, b, x[i + 11], 16, 1839030562);
			b = hh(b, c, d, a, x[i + 14], 23, -35309556);
			a = hh(a, b, c, d, x[i + 1], 4, -1530992060);
			d = hh(d, a, b, c, x[i + 4], 11, 1272893353);
			c = hh(c, d, a, b, x[i + 7], 16, -155497632);
			b = hh(b, c, d, a, x[i + 10], 23, -1094730640);
			a = hh(a, b, c, d, x[i + 13], 4, 681279174);
			d = hh(d, a, b, c, x[i + 0], 11, -358537222);
			c = hh(c, d, a, b, x[i + 3], 16, -722521979);
			b = hh(b, c, d, a, x[i + 6], 23, 76029189);
			a = hh(a, b, c, d, x[i + 9], 4, -640364487);
			d = hh(d, a, b, c, x[i + 12], 11, -421815835);
			c = hh(c, d, a, b, x[i + 15], 16, 530742520);
			b = hh(b, c, d, a, x[i + 2], 23, -995338651);
			a = ii(a, b, c, d, x[i + 0], 6, -198630844);
			d = ii(d, a, b, c, x[i + 7], 10, 1126891415);
			c = ii(c, d, a, b, x[i + 14], 15, -1416354905);
			b = ii(b, c, d, a, x[i + 5], 21, -57434055);
			a = ii(a, b, c, d, x[i + 12], 6, 1700485571);
			d = ii(d, a, b, c, x[i + 3], 10, -1894986606);
			c = ii(c, d, a, b, x[i + 10], 15, -1051523);
			b = ii(b, c, d, a, x[i + 1], 21, -2054922799);
			a = ii(a, b, c, d, x[i + 8], 6, 1873313359);
			d = ii(d, a, b, c, x[i + 15], 10, -30611744);
			c = ii(c, d, a, b, x[i + 6], 15, -1560198380);
			b = ii(b, c, d, a, x[i + 13], 21, 1309151649);
			a = ii(a, b, c, d, x[i + 4], 6, -145523070);
			d = ii(d, a, b, c, x[i + 11], 10, -1120210379);
			c = ii(c, d, a, b, x[i + 2], 15, 718787259);
			b = ii(b, c, d, a, x[i + 9], 21, -343485551);
			a = safe_add(a, olda);
			b = safe_add(b, oldb);
			c = safe_add(c, oldc);
			d = safe_add(d, oldd);
		}

		return [a, b, c, d];
	}

	var binl2hex = function(binarray) {
		var hex_tab = "0123456789abcdef", str = "", i, len=binarray.length*4;
		for (i=0; i<len; i++) {
			str += hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8 + 4)) & 0xF) + hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8)) & 0xF);
		}

		return str;
	}

	var str2binl = function(str) {
		var nblk = ((str.length + 8) >> 6) + 1;
		var blks = [], i, len=nblk*16, j, strlen=str.length;

		for (i=0; i<len; i++) {
			blks.push(0);
		}

		for (j=0; j<strlen; j++) {
			blks[j >> 2] |= (str.charCodeAt(j) & 0xFF) << ((j % 4) * 8);
		}

		blks[j >> 2] |= 0x80 << ((j % 4) * 8);
		blks[nblk*16 - 2] = strlen * 8;

		return blks;
	}

	return binl2hex(coreMD5(str2binl(this)));
};

// @example
// 'www.staypositive.ru'.md5()