Mercurial > hg > audiodb
diff bindings/as3/ext/com/adobe/crypto/MD5Stream.as @ 732:3a0b9700b3d2
* Initial AS3 commit
| author | mas01mj |
|---|---|
| date | Tue, 14 Sep 2010 16:47:10 +0000 |
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| children |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/bindings/as3/ext/com/adobe/crypto/MD5Stream.as Tue Sep 14 16:47:10 2010 +0000 @@ -0,0 +1,402 @@ +/* + Copyright (c) 2008, Adobe Systems Incorporated + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + + * Neither the name of Adobe Systems Incorporated nor the names of its + contributors may be used to endorse or promote products derived from + this software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS + IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR + CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + +package com.adobe.crypto +{ + import com.adobe.utils.IntUtil; + import flash.utils.ByteArray; + + /** + * Perform MD5 hash of an input stream in chunks. This class is + * based on com.adobe.crypto.MD5 and can process data in + * chunks. Both block creation and hash computation are done + * together for whatever input is available so that the memory + * overhead at a time is always fixed. Memory usage is governed by + * two parameters: one is the amount of data passed in to update() + * and the other is memoryBlockSize. The latter comes into play + * only when the memory window exceeds the pre allocated memory + * window of flash player. Usage: create an instance, call + * update(data) repeatedly for all chunks and finally complete() + * which will return the md5 hash. + */ + public class MD5Stream + { + private static var mask:int = 0xFF; + + private var arr:Array = []; + + /* running count of length */ + private var arrLen:int; + + // initialize the md buffers + private var a:int = 1732584193; + private var b:int = -271733879; + private var c:int = -1732584194; + private var d:int = 271733878; + + // variables to store previous values + private var aa:int; + private var bb:int; + private var cc:int; + private var dd:int; + + /* index for data read */ + private var arrIndexLen:int = 0; + /* index for hash computation */ + private var arrProcessIndex:int = 0; + /* index for removing stale arr values */ + private var cleanIndex:int = 0; + + /** + * Change this value from the default (16384) in the range of + * MBs to actually affect GC as GC allocates in pools of + * memory */ + public var memoryBlockSize:int = 16384; + + + public function MD5Stream() + { + + } + + + /** + * Pass in chunks of the input data with update(), call + * complete() with an optional chunk which will return the + * final hash. Equivalent to the way + * java.security.MessageDigest works. + * + * @param input The optional bytearray chunk which is the final part of the input + * @return A string containing the hash value + * @langversion ActionScript 3.0 + * @playerversion Flash 8.5 + * @tiptext + */ + public function complete(input:ByteArray=null):String + { + if ( arr.length == 0 ) + { + if ( input == null ) + { + throw new Error("null input to complete without prior call to update. At least an empty bytearray must be passed."); + } + } + + if ( input != null ) + { + readIntoArray(input); + } + + //pad, append length + padArray(arrLen); + + hashRemainingChunks(false); + + var res:String = IntUtil.toHex( a ) + IntUtil.toHex( b ) + + IntUtil.toHex( c ) + IntUtil.toHex( d ); + resetFields(); + + return res; + } + + /** + * Pass in chunks of the input data with update(), call + * complete() with an optional chunk which will return the + * final hash. Equivalent to the way + * java.security.MessageDigest works. + * + * @param input The bytearray chunk to perform the hash on + * @langversion ActionScript 3.0 + * @playerversion Flash 8.5 + * @tiptext + */ + public function update(input:ByteArray):void + { + readIntoArray(input); + hashRemainingChunks(); + } + + /** + * Re-initialize this instance for use to perform hashing on + * another input stream. This is called automatically by + * complete(). + * + * @langversion ActionScript 3.0 + * @playerversion Flash 8.5 + * @tiptext + */ + public function resetFields():void + { + //truncate array + arr.length = 0; + arrLen = 0; + + // initialize the md buffers + a = 1732584193; + b = -271733879; + c = -1732584194; + d = 271733878; + + // variables to store previous values + aa = 0; + bb = 0; + cc = 0; + dd = 0; + + arrIndexLen = 0; + arrProcessIndex = 0; + cleanIndex = 0; + } + + /** read into arr and free up used blocks of arr */ + private function readIntoArray(input:ByteArray):void + { + var closestChunkLen:int = input.length * 8; + arrLen += closestChunkLen; + + /* clean up memory. if there are entries in the array that + * are already processed and the amount is greater than + * memoryBlockSize, create a new array, copy the last + * block into it and let the old one get picked up by + * GC. */ + if ( arrProcessIndex - cleanIndex > memoryBlockSize ) + { + var newarr:Array= new Array(); + + /* AS Arrays in sparse arrays. arr[2002] can exist + * without values for arr[0] - arr[2001] */ + for ( var j:int = arrProcessIndex; j < arr.length; j++ ) + { + newarr[j] = arr[j]; + } + + cleanIndex = arrProcessIndex; + arr = null; + arr = newarr; + } + + for ( var k:int = 0; k < closestChunkLen; k+=8 ) + { + //discard high bytes (convert to uint) + arr[ int(arrIndexLen >> 5) ] |= ( input[ k / 8 ] & mask ) << ( arrIndexLen % 32 ); + arrIndexLen += 8; + } + + + } + + private function hashRemainingChunks(bUpdate:Boolean=true):void + { + var len:int = arr.length; + + /* leave a 16 word block untouched if we are called from + * update. This is because, padArray() can modify the last + * block and this modification has to happen before we + * compute the hash. */ + if ( bUpdate ) + { + len -= 16; + } + + /* don't do anything if don't have a 16 word block. */ + if ( arrProcessIndex >= len || len - arrProcessIndex < 15 ) + { + return; + } + + + for ( var i:int = arrProcessIndex; i < len ; i += 16, arrProcessIndex += 16) + { + // save previous values + aa = a; + bb = b; + cc = c; + dd = d; + + // Round 1 + a = ff( a, b, c, d, arr[int(i+ 0)], 7, -680876936 ); // 1 + d = ff( d, a, b, c, arr[int(i+ 1)], 12, -389564586 ); // 2 + c = ff( c, d, a, b, arr[int(i+ 2)], 17, 606105819 ); // 3 + b = ff( b, c, d, a, arr[int(i+ 3)], 22, -1044525330 ); // 4 + a = ff( a, b, c, d, arr[int(i+ 4)], 7, -176418897 ); // 5 + d = ff( d, a, b, c, arr[int(i+ 5)], 12, 1200080426 ); // 6 + c = ff( c, d, a, b, arr[int(i+ 6)], 17, -1473231341 ); // 7 + b = ff( b, c, d, a, arr[int(i+ 7)], 22, -45705983 ); // 8 + a = ff( a, b, c, d, arr[int(i+ 8)], 7, 1770035416 ); // 9 + d = ff( d, a, b, c, arr[int(i+ 9)], 12, -1958414417 ); // 10 + c = ff( c, d, a, b, arr[int(i+10)], 17, -42063 ); // 11 + b = ff( b, c, d, a, arr[int(i+11)], 22, -1990404162 ); // 12 + a = ff( a, b, c, d, arr[int(i+12)], 7, 1804603682 ); // 13 + d = ff( d, a, b, c, arr[int(i+13)], 12, -40341101 ); // 14 + c = ff( c, d, a, b, arr[int(i+14)], 17, -1502002290 ); // 15 + b = ff( b, c, d, a, arr[int(i+15)], 22, 1236535329 ); // 16 + + // Round 2 + a = gg( a, b, c, d, arr[int(i+ 1)], 5, -165796510 ); // 17 + d = gg( d, a, b, c, arr[int(i+ 6)], 9, -1069501632 ); // 18 + c = gg( c, d, a, b, arr[int(i+11)], 14, 643717713 ); // 19 + b = gg( b, c, d, a, arr[int(i+ 0)], 20, -373897302 ); // 20 + a = gg( a, b, c, d, arr[int(i+ 5)], 5, -701558691 ); // 21 + d = gg( d, a, b, c, arr[int(i+10)], 9, 38016083 ); // 22 + c = gg( c, d, a, b, arr[int(i+15)], 14, -660478335 ); // 23 + b = gg( b, c, d, a, arr[int(i+ 4)], 20, -405537848 ); // 24 + a = gg( a, b, c, d, arr[int(i+ 9)], 5, 568446438 ); // 25 + d = gg( d, a, b, c, arr[int(i+14)], 9, -1019803690 ); // 26 + c = gg( c, d, a, b, arr[int(i+ 3)], 14, -187363961 ); // 27 + b = gg( b, c, d, a, arr[int(i+ 8)], 20, 1163531501 ); // 28 + a = gg( a, b, c, d, arr[int(i+13)], 5, -1444681467 ); // 29 + d = gg( d, a, b, c, arr[int(i+ 2)], 9, -51403784 ); // 30 + c = gg( c, d, a, b, arr[int(i+ 7)], 14, 1735328473 ); // 31 + b = gg( b, c, d, a, arr[int(i+12)], 20, -1926607734 ); // 32 + + // Round 3 + a = hh( a, b, c, d, arr[int(i+ 5)], 4, -378558 ); // 33 + d = hh( d, a, b, c, arr[int(i+ 8)], 11, -2022574463 ); // 34 + c = hh( c, d, a, b, arr[int(i+11)], 16, 1839030562 ); // 35 + b = hh( b, c, d, a, arr[int(i+14)], 23, -35309556 ); // 36 + a = hh( a, b, c, d, arr[int(i+ 1)], 4, -1530992060 ); // 37 + d = hh( d, a, b, c, arr[int(i+ 4)], 11, 1272893353 ); // 38 + c = hh( c, d, a, b, arr[int(i+ 7)], 16, -155497632 ); // 39 + b = hh( b, c, d, a, arr[int(i+10)], 23, -1094730640 ); // 40 + a = hh( a, b, c, d, arr[int(i+13)], 4, 681279174 ); // 41 + d = hh( d, a, b, c, arr[int(i+ 0)], 11, -358537222 ); // 42 + c = hh( c, d, a, b, arr[int(i+ 3)], 16, -722521979 ); // 43 + b = hh( b, c, d, a, arr[int(i+ 6)], 23, 76029189 ); // 44 + a = hh( a, b, c, d, arr[int(i+ 9)], 4, -640364487 ); // 45 + d = hh( d, a, b, c, arr[int(i+12)], 11, -421815835 ); // 46 + c = hh( c, d, a, b, arr[int(i+15)], 16, 530742520 ); // 47 + b = hh( b, c, d, a, arr[int(i+ 2)], 23, -995338651 ); // 48 + + // Round 4 + a = ii( a, b, c, d, arr[int(i+ 0)], 6, -198630844 ); // 49 + d = ii( d, a, b, c, arr[int(i+ 7)], 10, 1126891415 ); // 50 + c = ii( c, d, a, b, arr[int(i+14)], 15, -1416354905 ); // 51 + b = ii( b, c, d, a, arr[int(i+ 5)], 21, -57434055 ); // 52 + a = ii( a, b, c, d, arr[int(i+12)], 6, 1700485571 ); // 53 + d = ii( d, a, b, c, arr[int(i+ 3)], 10, -1894986606 ); // 54 + c = ii( c, d, a, b, arr[int(i+10)], 15, -1051523 ); // 55 + b = ii( b, c, d, a, arr[int(i+ 1)], 21, -2054922799 ); // 56 + a = ii( a, b, c, d, arr[int(i+ 8)], 6, 1873313359 ); // 57 + d = ii( d, a, b, c, arr[int(i+15)], 10, -30611744 ); // 58 + c = ii( c, d, a, b, arr[int(i+ 6)], 15, -1560198380 ); // 59 + b = ii( b, c, d, a, arr[int(i+13)], 21, 1309151649 ); // 60 + a = ii( a, b, c, d, arr[int(i+ 4)], 6, -145523070 ); // 61 + d = ii( d, a, b, c, arr[int(i+11)], 10, -1120210379 ); // 62 + c = ii( c, d, a, b, arr[int(i+ 2)], 15, 718787259 ); // 63 + b = ii( b, c, d, a, arr[int(i+ 9)], 21, -343485551 ); // 64 + + a += aa; + b += bb; + c += cc; + d += dd; + + } + + } + + private function padArray(len:int):void + { + arr[ int(len >> 5) ] |= 0x80 << ( len % 32 ); + arr[ int(( ( ( len + 64 ) >>> 9 ) << 4 ) + 14) ] = len; + arrLen = arr.length; + } + + /* Code below same as com.adobe.crypto.MD5 */ + + /** + * Auxiliary function f as defined in RFC + */ + private static function f( x:int, y:int, z:int ):int { + return ( x & y ) | ( (~x) & z ); + } + + /** + * Auxiliary function g as defined in RFC + */ + private static function g( x:int, y:int, z:int ):int { + return ( x & z ) | ( y & (~z) ); + } + + /** + * Auxiliary function h as defined in RFC + */ + private static function h( x:int, y:int, z:int ):int { + return x ^ y ^ z; + } + + /** + * Auxiliary function i as defined in RFC + */ + private static function i( x:int, y:int, z:int ):int { + return y ^ ( x | (~z) ); + } + + /** + * A generic transformation function. The logic of ff, gg, hh, and + * ii are all the same, minus the function used, so pull that logic + * out and simplify the method bodies for the transoformation functions. + */ + private static function transform( func:Function, a:int, b:int, c:int, d:int, x:int, s:int, t:int):int { + var tmp:int = a + int( func( b, c, d ) ) + x + t; + return IntUtil.rol( tmp, s ) + b; + } + + /** + * ff transformation function + */ + private static function ff ( a:int, b:int, c:int, d:int, x:int, s:int, t:int ):int { + return transform( f, a, b, c, d, x, s, t ); + } + + /** + * gg transformation function + */ + private static function gg ( a:int, b:int, c:int, d:int, x:int, s:int, t:int ):int { + return transform( g, a, b, c, d, x, s, t ); + } + + /** + * hh transformation function + */ + private static function hh ( a:int, b:int, c:int, d:int, x:int, s:int, t:int ):int { + return transform( h, a, b, c, d, x, s, t ); + } + + /** + * ii transformation function + */ + private static function ii ( a:int, b:int, c:int, d:int, x:int, s:int, t:int ):int { + return transform( i, a, b, c, d, x, s, t ); + } + + } +} \ No newline at end of file