/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* SHA-1 implementation in JavaScript | (c) Chris Veness 2002-2010 | www.movable-type.co.uk */ /* - see http://csrc.nist.gov/groups/ST/toolkit/secure_hashing.html */ /* http://csrc.nist.gov/groups/ST/toolkit/examples.html */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ var Sha1 = {}; // Sha1 namespace /** * Generates SHA-1 hash of string * * @param {String} msg String to be hashed * @param {Boolean} [utf8encode=true] Encode msg as UTF-8 before generating hash * @returns {String} Hash of msg as hex character string */ Sha1.hash = function(msg, utf8encode) { utf8encode = (typeof utf8encode == 'undefined') ? true : utf8encode; // convert string to UTF-8, as SHA only deals with byte-streams if (utf8encode) msg = Utf8.encode(msg); // constants [§4.2.1] var K = [0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6]; // PREPROCESSING msg += String.fromCharCode(0x80); // add trailing '1' bit (+ 0's padding) to string [§5.1.1] // convert string msg into 512-bit/16-integer blocks arrays of ints [§5.2.1] var l = msg.length/4 + 2; // length (in 32-bit integers) of msg + ‘1’ + appended length var N = Math.ceil(l/16); // number of 16-integer-blocks required to hold 'l' ints var M = new Array(N); for (var i=0; i<N; i++) { M[i] = new Array(16); for (var j=0; j<16; j++) { // encode 4 chars per integer, big-endian encoding M[i][j] = (msg.charCodeAt(i*64+j*4)<<24) | (msg.charCodeAt(i*64+j*4+1)<<16) | (msg.charCodeAt(i*64+j*4+2)<<8) | (msg.charCodeAt(i*64+j*4+3)); } // note running off the end of msg is ok 'cos bitwise ops on NaN return 0 } // add length (in bits) into final pair of 32-bit integers (big-endian) [§5.1.1] // note: most significant word would be (len-1)*8 >>> 32, but since JS converts // bitwise-op args to 32 bits, we need to simulate this by arithmetic operators M[N-1][14] = ((msg.length-1)*8) / Math.pow(2, 32); M[N-1][14] = Math.floor(M[N-1][14]) M[N-1][15] = ((msg.length-1)*8) & 0xffffffff; // set initial hash value [§5.3.1] var H0 = 0x67452301; var H1 = 0xefcdab89; var H2 = 0x98badcfe; var H3 = 0x10325476; var H4 = 0xc3d2e1f0; // HASH COMPUTATION [§6.1.2] var W = new Array(80); var a, b, c, d, e; for (var i=0; i<N; i++) { // 1 - prepare message schedule 'W' for (var t=0; t<16; t++) W[t] = M[i][t]; for (var t=16; t<80; t++) W[t] = Sha1.ROTL(W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16], 1); // 2 - initialise five working variables a, b, c, d, e with previous hash value a = H0; b = H1; c = H2; d = H3; e = H4; // 3 - main loop for (var t=0; t<80; t++) { var s = Math.floor(t/20); // seq for blocks of 'f' functions and 'K' constants var T = (Sha1.ROTL(a,5) + Sha1.f(s,b,c,d) + e + K[s] + W[t]) & 0xffffffff; e = d; d = c; c = Sha1.ROTL(b, 30); b = a; a = T; } // 4 - compute the new intermediate hash value H0 = (H0+a) & 0xffffffff; // note 'addition modulo 2^32' H1 = (H1+b) & 0xffffffff; H2 = (H2+c) & 0xffffffff; H3 = (H3+d) & 0xffffffff; H4 = (H4+e) & 0xffffffff; } return Sha1.toHexStr(H0) + Sha1.toHexStr(H1) + Sha1.toHexStr(H2) + Sha1.toHexStr(H3) + Sha1.toHexStr(H4); } // // function 'f' [§4.1.1] // Sha1.f = function(s, x, y, z) { switch (s) { case 0: return (x & y) ^ (~x & z); // Ch() case 1: return x ^ y ^ z; // Parity() case 2: return (x & y) ^ (x & z) ^ (y & z); // Maj() case 3: return x ^ y ^ z; // Parity() } } // // rotate left (circular left shift) value x by n positions [§3.2.5] // Sha1.ROTL = function(x, n) { return (x<<n) | (x>>>(32-n)); } // // hexadecimal representation of a number // (note toString(16) is implementation-dependant, and // in IE returns signed numbers when used on full words) // Sha1.toHexStr = function(n) { var s="", v; for (var i=7; i>=0; i--) { v = (n>>>(i*4)) & 0xf; s += v.toString(16); } return s; } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* Utf8 class: encode / decode between multi-byte Unicode characters and UTF-8 multiple */ /* single-byte character encoding (c) Chris Veness 2002-2010 */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ var Utf8 = {}; // Utf8 namespace /** * Encode multi-byte Unicode string into utf-8 multiple single-byte characters * (BMP / basic multilingual plane only) * * Chars in range U+0080 - U+07FF are encoded in 2 chars, U+0800 - U+FFFF in 3 chars * * @param {String} strUni Unicode string to be encoded as UTF-8 * @returns {String} encoded string */ Utf8.encode = function(strUni) { // use regular expressions & String.replace callback function for better efficiency // than procedural approaches var strUtf = strUni.replace( /[\u0080-\u07ff]/g, // U+0080 - U+07FF => 2 bytes 110yyyyy, 10zzzzzz function(c) { var cc = c.charCodeAt(0); return String.fromCharCode(0xc0 | cc>>6, 0x80 | cc&0x3f); } ); strUtf = strUtf.replace( /[\u0800-\uffff]/g, // U+0800 - U+FFFF => 3 bytes 1110xxxx, 10yyyyyy, 10zzzzzz function(c) { var cc = c.charCodeAt(0); return String.fromCharCode(0xe0 | cc>>12, 0x80 | cc>>6&0x3F, 0x80 | cc&0x3f); } ); return strUtf; } /** * Decode utf-8 encoded string back into multi-byte Unicode characters * * @param {String} strUtf UTF-8 string to be decoded back to Unicode * @returns {String} decoded string */ Utf8.decode = function(strUtf) { // note: decode 3-byte chars first as decoded 2-byte strings could appear to be 3-byte char! var strUni = strUtf.replace( /[\u00e0-\u00ef][\u0080-\u00bf][\u0080-\u00bf]/g, // 3-byte chars function(c) { // (note parentheses for precence) var cc = ((c.charCodeAt(0)&0x0f)<<12) | ((c.charCodeAt(1)&0x3f)<<6) | ( c.charCodeAt(2)&0x3f); return String.fromCharCode(cc); } ); strUni = strUni.replace( /[\u00c0-\u00df][\u0080-\u00bf]/g, // 2-byte chars function(c) { // (note parentheses for precence) var cc = (c.charCodeAt(0)&0x1f)<<6 | c.charCodeAt(1)&0x3f; return String.fromCharCode(cc); } ); return strUni; } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */