Small improvements.

[platal.git] / htdocs / javascript / sha1.js

/*\r
 * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined\r
 * in FIPS PUB 180-1\r
 * Version 2.1a Copyright Paul Johnston 2000 - 2002.\r
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet\r
 * Distributed under the BSD License\r
 * See http://pajhome.org.uk/crypt/md5 for details.\r
 */\r
\r
/*\r
 * Configurable variables. You may need to tweak these to be compatible with\r
 * the server-side, but the defaults work in most cases.\r
 */\r
var hexcase = 0;  /* hex output format. 0 - lowercase; 1 - uppercase        */\r
var b64pad  = ""; /* base-64 pad character. "=" for strict RFC compliance   */\r
var chrsz   = 8;  /* bits per input character. 8 - ASCII; 16 - Unicode      */\r
\r
/*\r
 * These are the functions you'll usually want to call\r
 * They take string arguments and return either hex or base-64 encoded strings\r
 */\r
function hex_sha1(s){return binb2hex(core_sha1(str2binb(s),s.length * chrsz));}\r
function b64_sha1(s){return binb2b64(core_sha1(str2binb(s),s.length * chrsz));}\r
function str_sha1(s){return binb2str(core_sha1(str2binb(s),s.length * chrsz));}\r
function hex_hmac_sha1(key, data){ return binb2hex(core_hmac_sha1(key, data));}\r
function b64_hmac_sha1(key, data){ return binb2b64(core_hmac_sha1(key, data));}\r
function str_hmac_sha1(key, data){ return binb2str(core_hmac_sha1(key, data));}\r
\r
/*\r
 * Perform a simple self-test to see if the VM is working\r
 */\r
function sha1_vm_test()\r
{\r
  return hex_sha1("abc") == "a9993e364706816aba3e25717850c26c9cd0d89d";\r
}\r
\r
/*\r
 * Calculate the SHA-1 of an array of big-endian words, and a bit length\r
 */\r
function core_sha1(x, len)\r
{\r
  /* append padding */\r
  x[len >> 5] |= 0x80 << (24 - len % 32);\r
  x[((len + 64 >> 9) << 4) + 15] = len;\r
\r
  var w = Array(80);\r
  var a =  1732584193;\r
  var b = -271733879;\r
  var c = -1732584194;\r
  var d =  271733878;\r
  var e = -1009589776;\r
\r
  for(var i = 0; i < x.length; i += 16)\r
  {\r
    var olda = a;\r
    var oldb = b;\r
    var oldc = c;\r
    var oldd = d;\r
    var olde = e;\r
\r
    for(var j = 0; j < 80; j++)\r
    {\r
      if(j < 16) w[j] = x[i + j];\r
      else w[j] = rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);\r
      var t = safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)),\r
                       safe_add(safe_add(e, w[j]), sha1_kt(j)));\r
      e = d;\r
      d = c;\r
      c = rol(b, 30);\r
      b = a;\r
      a = t;\r
    }\r
\r
    a = safe_add(a, olda);\r
    b = safe_add(b, oldb);\r
    c = safe_add(c, oldc);\r
    d = safe_add(d, oldd);\r
    e = safe_add(e, olde);\r
  }\r
  return Array(a, b, c, d, e);\r
\r
}\r
\r
/*\r
 * Perform the appropriate triplet combination function for the current\r
 * iteration\r
 */\r
function sha1_ft(t, b, c, d)\r
{\r
  if(t < 20) return (b & c) | ((~b) & d);\r
  if(t < 40) return b ^ c ^ d;\r
  if(t < 60) return (b & c) | (b & d) | (c & d);\r
  return b ^ c ^ d;\r
}\r
\r
/*\r
 * Determine the appropriate additive constant for the current iteration\r
 */\r
function sha1_kt(t)\r
{\r
  return (t < 20) ?  1518500249 : (t < 40) ?  1859775393 :\r
         (t < 60) ? -1894007588 : -899497514;\r
}\r
\r
/*\r
 * Calculate the HMAC-SHA1 of a key and some data\r
 */\r
function core_hmac_sha1(key, data)\r
{\r
  var bkey = str2binb(key);\r
  if(bkey.length > 16) bkey = core_sha1(bkey, key.length * chrsz);\r
\r
  var ipad = Array(16), opad = Array(16);\r
  for(var i = 0; i < 16; i++)\r
  {\r
    ipad[i] = bkey[i] ^ 0x36363636;\r
    opad[i] = bkey[i] ^ 0x5C5C5C5C;\r
  }\r
\r
  var hash = core_sha1(ipad.concat(str2binb(data)), 512 + data.length * chrsz);\r
  return core_sha1(opad.concat(hash), 512 + 160);\r
}\r
\r
/*\r
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally\r
 * to work around bugs in some JS interpreters.\r
 */\r
function safe_add(x, y)\r
{\r
  var lsw = (x & 0xFFFF) + (y & 0xFFFF);\r
  var msw = (x >> 16) + (y >> 16) + (lsw >> 16);\r
  return (msw << 16) | (lsw & 0xFFFF);\r
}\r
\r
/*\r
 * Bitwise rotate a 32-bit number to the left.\r
 */\r
function rol(num, cnt)\r
{\r
  return (num << cnt) | (num >>> (32 - cnt));\r
}\r
\r
/*\r
 * Convert an 8-bit or 16-bit string to an array of big-endian words\r
 * In 8-bit function, characters >255 have their hi-byte silently ignored.\r
 */\r
function str2binb(str)\r
{\r
  var bin = Array();\r
  var mask = (1 << chrsz) - 1;\r
  for(var i = 0; i < str.length * chrsz; i += chrsz)\r
    bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (32 - chrsz - i%32);\r
  return bin;\r
}\r
\r
/*\r
 * Convert an array of big-endian words to a string\r
 */\r
function binb2str(bin)\r
{\r
  var str = "";\r
  var mask = (1 << chrsz) - 1;\r
  for(var i = 0; i < bin.length * 32; i += chrsz)\r
    str += String.fromCharCode((bin[i>>5] >>> (32 - chrsz - i%32)) & mask);\r
  return str;\r
}\r
\r
/*\r
 * Convert an array of big-endian words to a hex string.\r
 */\r
function binb2hex(binarray)\r
{\r
  var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";\r
  var str = "";\r
  for(var i = 0; i < binarray.length * 4; i++)\r
  {\r
    str += hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8+4)) & 0xF) +\r
           hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8  )) & 0xF);\r
  }\r
  return str;\r
}\r
\r
/*\r
 * Convert an array of big-endian words to a base-64 string\r
 */\r
function binb2b64(binarray)\r
{\r
  var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";\r
  var str = "";\r
  for(var i = 0; i < binarray.length * 4; i += 3)\r
  {\r
    var triplet = (((binarray[i   >> 2] >> 8 * (3 -  i   %4)) & 0xFF) << 16)\r
                | (((binarray[i+1 >> 2] >> 8 * (3 - (i+1)%4)) & 0xFF) << 8 )\r
                |  ((binarray[i+2 >> 2] >> 8 * (3 - (i+2)%4)) & 0xFF);\r
    for(var j = 0; j < 4; j++)\r
    {\r
      if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;\r
      else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);\r
    }\r
  }\r
  return str;\r
}\r
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