michael@0: /*
michael@0:  * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
michael@0:  * in FIPS PUB 180-1
michael@0:  * Version 2.1 Copyright Paul Johnston 2000 - 2002.
michael@0:  * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
michael@0:  * Distributed under the BSD License
michael@0:  * See http://pajhome.org.uk/crypt/md5 for details.
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  * Configurable variables. You may need to tweak these to be compatible with
michael@0:  * the server-side, but the defaults work in most cases.
michael@0:  */
michael@0: var hexcase = 0;  /* hex output format. 0 - lowercase; 1 - uppercase        */
michael@0: var b64pad  = ""; /* base-64 pad character. "=" for strict RFC compliance   */
michael@0: var chrsz   = 8;  /* bits per input character. 8 - ASCII; 16 - Unicode      */
michael@0: 
michael@0: /*
michael@0:  * These are the functions you'll usually want to call
michael@0:  * They take string arguments and return either hex or base-64 encoded strings
michael@0:  */
michael@0: function hexsha1(s){return binb2hex(coresha1(str2binb(s),s.length * chrsz));}
michael@0: function b64sha1(s){return binb2b64(coresha1(str2binb(s),s.length * chrsz));}
michael@0: function strsha1(s){return binb2str(coresha1(str2binb(s),s.length * chrsz));}
michael@0: function hexhmacsha1(key, data){ return binb2hex(corehmacsha1(key, data));}
michael@0: function b64hmacsha1(key, data){ return binb2b64(corehmacsha1(key, data));}
michael@0: function strhmacsha1(key, data){ return binb2str(corehmacsha1(key, data));}
michael@0: 
michael@0: /*
michael@0:  * Perform a simple self-test to see if the VM is working
michael@0:  */
michael@0: function sha1vmtest()
michael@0: {
michael@0:   return hexsha1("abc") == "a9993e364706816aba3e25717850c26c9cd0d89d";
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Calculate the SHA-1 of an array of big-endian words, and a bit length
michael@0:  */
michael@0: function coresha1(x, len)
michael@0: {
michael@0:   /* append padding */
michael@0:   x[len >> 5] |= 0x80 << (24 - len % 32);
michael@0:   x[((len + 64 >> 9) << 4) + 15] = len;
michael@0: 
michael@0:   var w = Array(80);
michael@0:   var a =  1732584193;
michael@0:   var b = -271733879;
michael@0:   var c = -1732584194;
michael@0:   var d =  271733878;
michael@0:   var e = -1009589776;
michael@0: 
michael@0:   for(var i = 0; i < x.length; i += 16)
michael@0:   {
michael@0:     var olda = a;
michael@0:     var oldb = b;
michael@0:     var oldc = c;
michael@0:     var oldd = d;
michael@0:     var olde = e;
michael@0: 
michael@0:     for(var j = 0; j < 80; j++)
michael@0:     {
michael@0:       if(j < 16) w[j] = x[i + j];
michael@0:       else w[j] = rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);
michael@0:       var t = safeadd(safeadd(rol(a, 5), sha1ft(j, b, c, d)), 
michael@0:                        safeadd(safeadd(e, w[j]), sha1kt(j)));
michael@0:       e = d;
michael@0:       d = c;
michael@0:       c = rol(b, 30);
michael@0:       b = a;
michael@0:       a = t;
michael@0:     }
michael@0: 
michael@0:     a = safeadd(a, olda);
michael@0:     b = safeadd(b, oldb);
michael@0:     c = safeadd(c, oldc);
michael@0:     d = safeadd(d, oldd);
michael@0:     e = safeadd(e, olde);
michael@0:   }
michael@0:   return Array(a, b, c, d, e);
michael@0:   
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Perform the appropriate triplet combination function for the current
michael@0:  * iteration
michael@0:  */
michael@0: function sha1ft(t, b, c, d)
michael@0: {
michael@0:   if(t < 20) return (b & c) | ((~b) & d);
michael@0:   if(t < 40) return b ^ c ^ d;
michael@0:   if(t < 60) return (b & c) | (b & d) | (c & d);
michael@0:   return b ^ c ^ d;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Determine the appropriate additive constant for the current iteration
michael@0:  */
michael@0: function sha1kt(t)
michael@0: {
michael@0:   return (t < 20) ?  1518500249 : (t < 40) ?  1859775393 :
michael@0:          (t < 60) ? -1894007588 : -899497514;
michael@0: }  
michael@0: 
michael@0: /*
michael@0:  * Calculate the HMAC-SHA1 of a key and some data
michael@0:  */
michael@0: function corehmacsha1(key, data)
michael@0: {
michael@0:   var bkey = str2binb(key);
michael@0:   if(bkey.length > 16) bkey = coresha1(bkey, key.length * chrsz);
michael@0: 
michael@0:   var ipad = Array(16), opad = Array(16);
michael@0:   for(var i = 0; i < 16; i++) 
michael@0:   {
michael@0:     ipad[i] = bkey[i] ^ 0x36363636;
michael@0:     opad[i] = bkey[i] ^ 0x5C5C5C5C;
michael@0:   }
michael@0: 
michael@0:   var hash = coresha1(ipad.concat(str2binb(data)), 512 + data.length * chrsz);
michael@0:   return coresha1(opad.concat(hash), 512 + 160);
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Add integers, wrapping at 2^32. This uses 16-bit operations internally
michael@0:  * to work around bugs in some JS interpreters.
michael@0:  */
michael@0: function safeadd(x, y)
michael@0: {
michael@0:   var lsw = (x & 0xFFFF) + (y & 0xFFFF);
michael@0:   var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
michael@0:   return (msw << 16) | (lsw & 0xFFFF);
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Bitwise rotate a 32-bit number to the left.
michael@0:  */
michael@0: function rol(num, cnt)
michael@0: {
michael@0:   return (num << cnt) | (num >>> (32 - cnt));
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Convert an 8-bit or 16-bit string to an array of big-endian words
michael@0:  * In 8-bit function, characters >255 have their hi-byte silently ignored.
michael@0:  */
michael@0: function str2binb(str)
michael@0: {
michael@0:   var bin = Array();
michael@0:   var mask = (1 << chrsz) - 1;
michael@0:   for(var i = 0; i < str.length * chrsz; i += chrsz)
michael@0:     bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (24 - i%32);
michael@0:   return bin;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Convert an array of big-endian words to a string
michael@0:  */
michael@0: function binb2str(bin)
michael@0: {
michael@0:   var str = "";
michael@0:   var mask = (1 << chrsz) - 1;
michael@0:   for(var i = 0; i < bin.length * 32; i += chrsz)
michael@0:     str += String.fromCharCode((bin[i>>5] >>> (24 - i%32)) & mask);
michael@0:   return str;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Convert an array of big-endian words to a hex string.
michael@0:  */
michael@0: function binb2hex(binarray)
michael@0: {
michael@0:   var hextab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
michael@0:   var str = "";
michael@0:   for(var i = 0; i < binarray.length * 4; i++)
michael@0:   {
michael@0:     str += hextab.charAt((binarray[i>>2] >> ((3 - i%4)*8+4)) & 0xF) +
michael@0:            hextab.charAt((binarray[i>>2] >> ((3 - i%4)*8  )) & 0xF);
michael@0:   }
michael@0:   return str;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Convert an array of big-endian words to a base-64 string
michael@0:  */
michael@0: function binb2b64(binarray)
michael@0: {
michael@0:   var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
michael@0:   var str = "";
michael@0:   for(var i = 0; i < binarray.length * 4; i += 3)
michael@0:   {
michael@0:     var triplet = (((binarray[i   >> 2] >> 8 * (3 -  i   %4)) & 0xFF) << 16)
michael@0:                 | (((binarray[i+1 >> 2] >> 8 * (3 - (i+1)%4)) & 0xFF) << 8 )
michael@0:                 |  ((binarray[i+2 >> 2] >> 8 * (3 - (i+2)%4)) & 0xFF);
michael@0:     for(var j = 0; j < 4; j++)
michael@0:     {
michael@0:       if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
michael@0:       else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
michael@0:     }
michael@0:   }
michael@0:   return str;
michael@0: }