michael@14: /*
michael@14:  * A JavaScript implementation of the RSA Data Security, Inc. MD4 Message
michael@14:  * Digest Algorithm, as defined in RFC 1320.
michael@14:  * Version 2.1 Copyright (C) Jerrad Pierce, Paul Johnston 1999 - 2002.
michael@14:  * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
michael@14:  * Distributed under the BSD License
michael@14:  * See http://pajhome.org.uk/crypt/md5 for more info.
michael@14:  */
michael@14: 
michael@14: /*
michael@14:  * Configurable variables. You may need to tweak these to be compatible with
michael@14:  * the server-side, but the defaults work in most cases.
michael@14:  */
michael@14: var hexcase = 0;  /* hex output format. 0 - lowercase; 1 - uppercase        */
michael@14: var b64pad  = ""; /* base-64 pad character. "=" for strict RFC compliance   */
michael@14: var chrsz   = 8;  /* bits per input character. 8 - ASCII; 16 - Unicode      */
michael@14: 
michael@14: /*
michael@14:  * These are the functions you'll usually want to call
michael@14:  */
michael@14: function hexmd4(s){ return binl2hex(coremd4(str2binl(s), s.length * chrsz));}
michael@14: function b64md4(s){ return binl2b64(coremd4(str2binl(s), s.length * chrsz));}
michael@14: function strmd4(s){ return binl2str(coremd4(str2binl(s), s.length * chrsz));}
michael@14: function hexhmacmd4(key, data) { return binl2hex(corehmacmd4(key, data)); }
michael@14: function b64hmacmd4(key, data) { return binl2b64(corehmacmd4(key, data)); }
michael@14: function strhmacmd4(key, data) { return binl2str(corehmacmd4(key, data)); }
michael@14: 
michael@14: /* 
michael@14:  * Perform a simple self-test to see if the VM is working 
michael@14:  */
michael@14: function md4vmtest()
michael@14: {
michael@14:   return hexmd4("abc") == "a448017aaf21d8525fc10ae87aa6729d";
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Calculate the MD4 of an array of little-endian words, and a bit length
michael@14:  */
michael@14: function coremd4(x, len)
michael@14: {
michael@14:   /* append padding */
michael@14:   x[len >> 5] |= 0x80 << (len % 32);
michael@14:   x[(((len + 64) >>> 9) << 4) + 14] = len;
michael@14:   
michael@14:   var a =  1732584193;
michael@14:   var b = -271733879;
michael@14:   var c = -1732584194;
michael@14:   var d =  271733878;
michael@14: 
michael@14:   for(var i = 0; i < x.length; i += 16)
michael@14:   {
michael@14:     var olda = a;
michael@14:     var oldb = b;
michael@14:     var oldc = c;
michael@14:     var oldd = d;
michael@14: 
michael@14:     a = md4ff(a, b, c, d, x[i+ 0], 3 );
michael@14:     d = md4ff(d, a, b, c, x[i+ 1], 7 );
michael@14:     c = md4ff(c, d, a, b, x[i+ 2], 11);
michael@14:     b = md4ff(b, c, d, a, x[i+ 3], 19);
michael@14:     a = md4ff(a, b, c, d, x[i+ 4], 3 );
michael@14:     d = md4ff(d, a, b, c, x[i+ 5], 7 );
michael@14:     c = md4ff(c, d, a, b, x[i+ 6], 11);
michael@14:     b = md4ff(b, c, d, a, x[i+ 7], 19);
michael@14:     a = md4ff(a, b, c, d, x[i+ 8], 3 );
michael@14:     d = md4ff(d, a, b, c, x[i+ 9], 7 );
michael@14:     c = md4ff(c, d, a, b, x[i+10], 11);
michael@14:     b = md4ff(b, c, d, a, x[i+11], 19);
michael@14:     a = md4ff(a, b, c, d, x[i+12], 3 );
michael@14:     d = md4ff(d, a, b, c, x[i+13], 7 );
michael@14:     c = md4ff(c, d, a, b, x[i+14], 11);
michael@14:     b = md4ff(b, c, d, a, x[i+15], 19);
michael@14: 
michael@14:     a = md4gg(a, b, c, d, x[i+ 0], 3 );
michael@14:     d = md4gg(d, a, b, c, x[i+ 4], 5 );
michael@14:     c = md4gg(c, d, a, b, x[i+ 8], 9 );
michael@14:     b = md4gg(b, c, d, a, x[i+12], 13);
michael@14:     a = md4gg(a, b, c, d, x[i+ 1], 3 );
michael@14:     d = md4gg(d, a, b, c, x[i+ 5], 5 );
michael@14:     c = md4gg(c, d, a, b, x[i+ 9], 9 );
michael@14:     b = md4gg(b, c, d, a, x[i+13], 13);
michael@14:     a = md4gg(a, b, c, d, x[i+ 2], 3 );
michael@14:     d = md4gg(d, a, b, c, x[i+ 6], 5 );
michael@14:     c = md4gg(c, d, a, b, x[i+10], 9 );
michael@14:     b = md4gg(b, c, d, a, x[i+14], 13);
michael@14:     a = md4gg(a, b, c, d, x[i+ 3], 3 );
michael@14:     d = md4gg(d, a, b, c, x[i+ 7], 5 );
michael@14:     c = md4gg(c, d, a, b, x[i+11], 9 );
michael@14:     b = md4gg(b, c, d, a, x[i+15], 13);
michael@14: 
michael@14:     a = md4hh(a, b, c, d, x[i+ 0], 3 );
michael@14:     d = md4hh(d, a, b, c, x[i+ 8], 9 );
michael@14:     c = md4hh(c, d, a, b, x[i+ 4], 11);
michael@14:     b = md4hh(b, c, d, a, x[i+12], 15);
michael@14:     a = md4hh(a, b, c, d, x[i+ 2], 3 );
michael@14:     d = md4hh(d, a, b, c, x[i+10], 9 );
michael@14:     c = md4hh(c, d, a, b, x[i+ 6], 11);
michael@14:     b = md4hh(b, c, d, a, x[i+14], 15);
michael@14:     a = md4hh(a, b, c, d, x[i+ 1], 3 );
michael@14:     d = md4hh(d, a, b, c, x[i+ 9], 9 );
michael@14:     c = md4hh(c, d, a, b, x[i+ 5], 11);
michael@14:     b = md4hh(b, c, d, a, x[i+13], 15);
michael@14:     a = md4hh(a, b, c, d, x[i+ 3], 3 );
michael@14:     d = md4hh(d, a, b, c, x[i+11], 9 );
michael@14:     c = md4hh(c, d, a, b, x[i+ 7], 11);
michael@14:     b = md4hh(b, c, d, a, x[i+15], 15);
michael@14: 
michael@14:     a = safeadd(a, olda);
michael@14:     b = safeadd(b, oldb);
michael@14:     c = safeadd(c, oldc);
michael@14:     d = safeadd(d, oldd);
michael@14: 
michael@14:   }
michael@14:   return Array(a, b, c, d);
michael@14: 
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * These functions implement the basic operation for each round of the
michael@14:  * algorithm.
michael@14:  */
michael@14: function md4cmn(q, a, b, x, s, t)
michael@14: {
michael@14:   return safeadd(rol(safeadd(safeadd(a, q), safeadd(x, t)), s), b);
michael@14: }
michael@14: function md4ff(a, b, c, d, x, s)
michael@14: {
michael@14:   return md4cmn((b & c) | ((~b) & d), a, 0, x, s, 0);
michael@14: }
michael@14: function md4gg(a, b, c, d, x, s)
michael@14: {
michael@14:   return md4cmn((b & c) | (b & d) | (c & d), a, 0, x, s, 1518500249);
michael@14: }
michael@14: function md4hh(a, b, c, d, x, s)
michael@14: {
michael@14:   return md4cmn(b ^ c ^ d, a, 0, x, s, 1859775393);
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Calculate the HMAC-MD4, of a key and some data
michael@14:  */
michael@14: function corehmacmd4(key, data)
michael@14: {
michael@14:   var bkey = str2binl(key);
michael@14:   if(bkey.length > 16) bkey = coremd4(bkey, key.length * chrsz);
michael@14: 
michael@14:   var ipad = Array(16), opad = Array(16);
michael@14:   for(var i = 0; i < 16; i++) 
michael@14:   {
michael@14:     ipad[i] = bkey[i] ^ 0x36363636;
michael@14:     opad[i] = bkey[i] ^ 0x5C5C5C5C;
michael@14:   }
michael@14: 
michael@14:   var hash = coremd4(ipad.concat(str2binl(data)), 512 + data.length * chrsz);
michael@14:   return coremd4(opad.concat(hash), 512 + 128);
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Add integers, wrapping at 2^32. This uses 16-bit operations internally
michael@14:  * to work around bugs in some JS interpreters.
michael@14:  */
michael@14: function safeadd(x, y)
michael@14: {
michael@14:   var lsw = (x & 0xFFFF) + (y & 0xFFFF);
michael@14:   var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
michael@14:   return (msw << 16) | (lsw & 0xFFFF);
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Bitwise rotate a 32-bit number to the left.
michael@14:  */
michael@14: function rol(num, cnt)
michael@14: {
michael@14:   return (num << cnt) | (num >>> (32 - cnt));
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Convert a string to an array of little-endian words
michael@14:  * If chrsz is ASCII, characters >255 have their hi-byte silently ignored.
michael@14:  */
michael@14: function str2binl(str)
michael@14: {
michael@14:   var bin = Array();
michael@14:   var mask = (1 << chrsz) - 1;
michael@14:   for(var i = 0; i < str.length * chrsz; i += chrsz)
michael@14:     bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (i%32);
michael@14:   return bin;
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Convert an array of little-endian words to a string
michael@14:  */
michael@14: function binl2str(bin)
michael@14: {
michael@14:   var str = "";
michael@14:   var mask = (1 << chrsz) - 1;
michael@14:   for(var i = 0; i < bin.length * 32; i += chrsz)
michael@14:     str += String.fromCharCode((bin[i>>5] >>> (i % 32)) & mask);
michael@14:   return str;
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Convert an array of little-endian words to a hex string.
michael@14:  */
michael@14: function binl2hex(binarray)
michael@14: {
michael@14:   var hextab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
michael@14:   var str = "";
michael@14:   for(var i = 0; i < binarray.length * 4; i++)
michael@14:   {
michael@14:     str += hextab.charAt((binarray[i>>2] >> ((i%4)*8+4)) & 0xF) +
michael@14:            hextab.charAt((binarray[i>>2] >> ((i%4)*8  )) & 0xF);
michael@14:   }
michael@14:   return str;
michael@14: }
michael@14: 
michael@14: /*
michael@14:  * Convert an array of little-endian words to a base-64 string
michael@14:  */
michael@14: function binl2b64(binarray)
michael@14: {
michael@14:   var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
michael@14:   var str = "";
michael@14:   for(var i = 0; i < binarray.length * 4; i += 3)
michael@14:   {
michael@14:     var triplet = (((binarray[i   >> 2] >> 8 * ( i   %4)) & 0xFF) << 16)
michael@14:                 | (((binarray[i+1 >> 2] >> 8 * ((i+1)%4)) & 0xFF) << 8 )
michael@14:                 |  ((binarray[i+2 >> 2] >> 8 * ((i+2)%4)) & 0xFF);
michael@14:     for(var j = 0; j < 4; j++)
michael@14:     {
michael@14:       if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
michael@14:       else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
michael@14:     }
michael@14:   }
michael@14:   return str;
michael@14: }