diff options
Diffstat (limited to 'app/assets/javascripts/srp/lib/rng.js')
| -rw-r--r-- | app/assets/javascripts/srp/lib/rng.js | 99 | 
1 files changed, 99 insertions, 0 deletions
| diff --git a/app/assets/javascripts/srp/lib/rng.js b/app/assets/javascripts/srp/lib/rng.js new file mode 100644 index 0000000..8d8de48 --- /dev/null +++ b/app/assets/javascripts/srp/lib/rng.js @@ -0,0 +1,99 @@ +/* + * Copyright (c) 2003-2005  Tom Wu + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,  + * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY  + * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.   + * + * IN NO EVENT SHALL TOM WU BE LIABLE FOR ANY SPECIAL, INCIDENTAL, + * INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER + * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER OR NOT ADVISED OF + * THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF LIABILITY, ARISING OUT + * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + * In addition, the following condition applies: + * + * All redistributions must retain an intact copy of this copyright notice + * and disclaimer. + */ + +// Random number generator - requires a PRNG backend, e.g. prng4.js + +// For best results, put code like +// <body onClick='rng_seed_time();' onKeyPress='rng_seed_time();'> +// in your main HTML document. + +var rng_state; +var rng_pool; +var rng_pptr; + +// Mix in a 32-bit integer into the pool +function rng_seed_int(x) { +  rng_pool[rng_pptr++] ^= x & 255; +  rng_pool[rng_pptr++] ^= (x >> 8) & 255; +  rng_pool[rng_pptr++] ^= (x >> 16) & 255; +  rng_pool[rng_pptr++] ^= (x >> 24) & 255; +  if(rng_pptr >= rng_psize) rng_pptr -= rng_psize; +} + +// Mix in the current time (w/milliseconds) into the pool +function rng_seed_time() { +  rng_seed_int(new Date().getTime()); +} + +// Initialize the pool with junk if needed. +if(rng_pool == null) { +  rng_pool = new Array(); +  rng_pptr = 0; +  var t; +  if(navigator.appName == "Netscape" && navigator.appVersion < "5" && window.crypto) { +    // Extract entropy (256 bits) from NS4 RNG if available +    var z = window.crypto.random(32); +    for(t = 0; t < z.length; ++t) +      rng_pool[rng_pptr++] = z.charCodeAt(t) & 255; +  }   +  while(rng_pptr < rng_psize) {  // extract some randomness from Math.random() +    t = Math.floor(65536 * Math.random()); +    rng_pool[rng_pptr++] = t >>> 8; +    rng_pool[rng_pptr++] = t & 255; +  } +  rng_pptr = 0; +  rng_seed_time(); +  //rng_seed_int(window.screenX); +  //rng_seed_int(window.screenY); +} + +function rng_get_byte() { +  if(rng_state == null) { +    rng_seed_time(); +    rng_state = prng_newstate(); +    rng_state.init(rng_pool); +    for(rng_pptr = 0; rng_pptr < rng_pool.length; ++rng_pptr) +      rng_pool[rng_pptr] = 0; +    rng_pptr = 0; +    //rng_pool = null; +  } +  // TODO: allow reseeding after first request +  return rng_state.next(); +} + +function rng_get_bytes(ba) { +  var i; +  for(i = 0; i < ba.length; ++i) ba[i] = rng_get_byte(); +} + +function SecureRandom() {} + +SecureRandom.prototype.nextBytes = rng_get_bytes; | 
