/* * 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 // // in your main HTML document. var rng_state = null; var rng_pool = null; var rng_pptr = null; // Konstruktor fuer SecureRandom function SecureRandom() { this.nextBytes = rng_get_bytes; } // 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; if( ( navigator.appName == "Netscape" ) && ( navigator.appVersion < "5" ) && ( window.crypto ) ) { // Extract entropy (256 bits) from NS4 RNG if available // FIXME (8.x) Das geht nur im NS4. Brauchen wir das dann? var randomString = window.crypto.random(32); for( var counter = 0; counter < randomString.length; ++counter ) { rng_pool[rng_pptr++] = randomString.charCodeAt( counter ) & 255; } } // extract some randomness from Math.random() var tempRandom = null; while(rng_pptr < rng_psize) { tempRandom = Math.floor( 65536 * Math.random() ); rng_pool[rng_pptr++] = tempRandom >>> 8; rng_pool[rng_pptr++] = tempRandom & 255; } rng_pptr = 0; rng_seed_time(); } 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; } // TODO: allow reseeding after first request return ( rng_state.next() ); } function rng_get_bytes( byteArray ) { for( var counter = 0; counter < byteArray.length; ++counter) { byteArray[counter] = rng_get_byte(); } }