80 lines
2.4 KiB
JavaScript
80 lines
2.4 KiB
JavaScript
// Downloaded from http://www-cs-students.stanford.edu/~tjw/jsbn/ by Jeremy White on 6/1/2012
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/*
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* Copyright (c) 2003-2005 Tom Wu
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* All Rights Reserved.
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
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* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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*
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* IN NO EVENT SHALL TOM WU BE LIABLE FOR ANY SPECIAL, INCIDENTAL,
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* INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER
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* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER OR NOT ADVISED OF
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* THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF LIABILITY, ARISING OUT
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* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*
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* In addition, the following condition applies:
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*
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* All redistributions must retain an intact copy of this copyright notice
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* and disclaimer.
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*/
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// prng4.js - uses Arcfour as a PRNG
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function Arcfour() {
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this.i = 0;
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this.j = 0;
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this.S = new Array();
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}
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// Initialize arcfour context from key, an array of ints, each from [0..255]
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function ARC4init(key) {
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var i, j, t;
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for(i = 0; i < 256; ++i)
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this.S[i] = i;
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j = 0;
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for(i = 0; i < 256; ++i) {
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j = (j + this.S[i] + key[i % key.length]) & 255;
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t = this.S[i];
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this.S[i] = this.S[j];
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this.S[j] = t;
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}
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this.i = 0;
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this.j = 0;
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}
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function ARC4next() {
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var t;
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this.i = (this.i + 1) & 255;
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this.j = (this.j + this.S[this.i]) & 255;
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t = this.S[this.i];
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this.S[this.i] = this.S[this.j];
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this.S[this.j] = t;
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return this.S[(t + this.S[this.i]) & 255];
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}
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Arcfour.prototype.init = ARC4init;
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Arcfour.prototype.next = ARC4next;
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// Plug in your RNG constructor here
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function prng_newstate() {
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return new Arcfour();
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}
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// Pool size must be a multiple of 4 and greater than 32.
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// An array of bytes the size of the pool will be passed to init()
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var rng_psize = 256;
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