htdocs/javascript/sha1.js

   1 /*
   2  * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
   3  * in FIPS PUB 180-1
   4  * Version 2.1a Copyright Paul Johnston 2000 - 2002.
   5  * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
   6  * Distributed under the BSD License
   7  * See http://pajhome.org.uk/crypt/md5 for details.
   8  */
   9
  10 /*
  11  * Configurable variables. You may need to tweak these to be compatible with
  12  * the server-side, but the defaults work in most cases.
  13  */
  14 var hexcase = 0;  /* hex output format. 0 - lowercase; 1 - uppercase        */
  15 var b64pad  = ""; /* base-64 pad character. "=" for strict RFC compliance   */
  16 var chrsz   = 8;  /* bits per input character. 8 - ASCII; 16 - Unicode      */
  17
  18 /*
  19  * These are the functions you'll usually want to call
  20  * They take string arguments and return either hex or base-64 encoded strings
  21  */
  22 function hex_sha1(s){return binb2hex(core_sha1(str2binb(s),s.length * chrsz));}
  23 function b64_sha1(s){return binb2b64(core_sha1(str2binb(s),s.length * chrsz));}
  24 function str_sha1(s){return binb2str(core_sha1(str2binb(s),s.length * chrsz));}
  25 function hex_hmac_sha1(key, data){ return binb2hex(core_hmac_sha1(key, data));}
  26 function b64_hmac_sha1(key, data){ return binb2b64(core_hmac_sha1(key, data));}
  27 function str_hmac_sha1(key, data){ return binb2str(core_hmac_sha1(key, data));}
  28
  29 /*
  30  * Perform a simple self-test to see if the VM is working
  31  */
  32 function sha1_vm_test()
  33 {
  34   return hex_sha1("abc") == "a9993e364706816aba3e25717850c26c9cd0d89d";
  35 }
  36
  37 /*
  38  * Calculate the SHA-1 of an array of big-endian words, and a bit length
  39  */
  40 function core_sha1(x, len)
  41 {
  42   /* append padding */
  43   x[len >> 5] |= 0x80 << (24 - len % 32);
  44   x[((len + 64 >> 9) << 4) + 15] = len;
  45
  46   var w = Array(80);
  47   var a =  1732584193;
  48   var b = -271733879;
  49   var c = -1732584194;
  50   var d =  271733878;
  51   var e = -1009589776;
  52
  53   for(var i = 0; i < x.length; i += 16)
  54   {
  55     var olda = a;
  56     var oldb = b;
  57     var oldc = c;
  58     var oldd = d;
  59     var olde = e;
  60
  61     for(var j = 0; j < 80; j++)
  62     {
  63       if(j < 16) w[j] = x[i + j];
  64       else w[j] = rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);
  65       var t = safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)),
  66                        safe_add(safe_add(e, w[j]), sha1_kt(j)));
  67       e = d;
  68       d = c;
  69       c = rol(b, 30);
  70       b = a;
  71       a = t;
  72     }
  73
  74     a = safe_add(a, olda);
  75     b = safe_add(b, oldb);
  76     c = safe_add(c, oldc);
  77     d = safe_add(d, oldd);
  78     e = safe_add(e, olde);
  79   }
  80   return Array(a, b, c, d, e);
  81
  82 }
  83
  84 /*
  85  * Perform the appropriate triplet combination function for the current
  86  * iteration
  87  */
  88 function sha1_ft(t, b, c, d)
  89 {
  90   if(t < 20) return (b & c) | ((~b) & d);
  91   if(t < 40) return b ^ c ^ d;
  92   if(t < 60) return (b & c) | (b & d) | (c & d);
  93   return b ^ c ^ d;
  94 }
  95
  96 /*
  97  * Determine the appropriate additive constant for the current iteration
  98  */
  99 function sha1_kt(t)
 100 {
 101   return (t < 20) ?  1518500249 : (t < 40) ?  1859775393 :
 102          (t < 60) ? -1894007588 : -899497514;
 103 }
 104
 105 /*
 106  * Calculate the HMAC-SHA1 of a key and some data
 107  */
 108 function core_hmac_sha1(key, data)
 109 {
 110   var bkey = str2binb(key);
 111   if(bkey.length > 16) bkey = core_sha1(bkey, key.length * chrsz);
 112
 113   var ipad = Array(16), opad = Array(16);
 114   for(var i = 0; i < 16; i++)
 115   {
 116     ipad[i] = bkey[i] ^ 0x36363636;
 117     opad[i] = bkey[i] ^ 0x5C5C5C5C;
 118   }
 119
 120   var hash = core_sha1(ipad.concat(str2binb(data)), 512 + data.length * chrsz);
 121   return core_sha1(opad.concat(hash), 512 + 160);
 122 }
 123
 124 /*
 125  * Add integers, wrapping at 2^32. This uses 16-bit operations internally
 126  * to work around bugs in some JS interpreters.
 127  */
 128 function safe_add(x, y)
 129 {
 130   var lsw = (x & 0xFFFF) + (y & 0xFFFF);
 131   var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
 132   return (msw << 16) | (lsw & 0xFFFF);
 133 }
 134
 135 /*
 136  * Bitwise rotate a 32-bit number to the left.
 137  */
 138 function rol(num, cnt)
 139 {
 140   return (num << cnt) | (num >>> (32 - cnt));
 141 }
 142
 143 /*
 144  * Convert an 8-bit or 16-bit string to an array of big-endian words
 145  * In 8-bit function, characters >255 have their hi-byte silently ignored.
 146  */
 147 function str2binb(str)
 148 {
 149   var bin = Array();
 150   var mask = (1 << chrsz) - 1;
 151   for(var i = 0; i < str.length * chrsz; i += chrsz)
 152     bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (32 - chrsz - i%32);
 153   return bin;
 154 }
 155
 156 /*
 157  * Convert an array of big-endian words to a string
 158  */
 159 function binb2str(bin)
 160 {
 161   var str = "";
 162   var mask = (1 << chrsz) - 1;
 163   for(var i = 0; i < bin.length * 32; i += chrsz)
 164     str += String.fromCharCode((bin[i>>5] >>> (32 - chrsz - i%32)) & mask);
 165   return str;
 166 }
 167
 168 /*
 169  * Convert an array of big-endian words to a hex string.
 170  */
 171 function binb2hex(binarray)
 172 {
 173   var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
 174   var str = "";
 175   for(var i = 0; i < binarray.length * 4; i++)
 176   {
 177     str += hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8+4)) & 0xF) +
 178            hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8  )) & 0xF);
 179   }
 180   return str;
 181 }
 182
 183 /*
 184  * Convert an array of big-endian words to a base-64 string
 185  */
 186 function binb2b64(binarray)
 187 {
 188   var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 189   var str = "";
 190   for(var i = 0; i < binarray.length * 4; i += 3)
 191   {
 192     var triplet = (((binarray[i   >> 2] >> 8 * (3 -  i   %4)) & 0xFF) << 16)
 193                 | (((binarray[i+1 >> 2] >> 8 * (3 - (i+1)%4)) & 0xFF) << 8 )
 194                 |  ((binarray[i+2 >> 2] >> 8 * (3 - (i+2)%4)) & 0xFF);
 195     for(var j = 0; j < 4; j++)
 196     {
 197       if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
 198       else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
 199     }
 200   }
 201   return str;
 202 }
 203 // vim:set et sw=4 sts=4 sws=4 foldmethod=marker enc=utf-8: