2 Copyright (c) 2008, Adobe Systems Incorporated
5 Redistribution and use in source and binary forms, with or without
6 modification, are permitted provided that the following conditions are
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14 documentation and/or other materials provided with the distribution.
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17 contributors may be used to endorse or promote products derived from
18 this software without specific prior written permission.
20 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
21 IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
22 THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
24 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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33 package com.adobe.crypto
35 import com.adobe.utils.IntUtil;
36 import flash.utils.ByteArray;
37 import mx.utils.Base64Encoder;
40 * The SHA-256 algorithm
42 * @see http://csrc.nist.gov/publications/fips/fips180-2/fips180-2withchangenotice.pdf
46 public static var digest:ByteArray;
48 * Performs the SHA256 hash algorithm on a string.
50 * @param s The string to hash
51 * @return A string containing the hash value of s
52 * @langversion ActionScript 3.0
56 public static function hash( s:String ):String {
57 var blocks:Array = createBlocksFromString( s );
58 var byteArray:ByteArray = hashBlocks( blocks );
60 return IntUtil.toHex( byteArray.readInt(), true )
61 + IntUtil.toHex( byteArray.readInt(), true )
62 + IntUtil.toHex( byteArray.readInt(), true )
63 + IntUtil.toHex( byteArray.readInt(), true )
64 + IntUtil.toHex( byteArray.readInt(), true )
65 + IntUtil.toHex( byteArray.readInt(), true )
66 + IntUtil.toHex( byteArray.readInt(), true )
67 + IntUtil.toHex( byteArray.readInt(), true );
71 * Performs the SHA256 hash algorithm on a ByteArray.
73 * @param data The ByteArray data to hash
74 * @return A string containing the hash value of data
75 * @langversion ActionScript 3.0
78 public static function hashBytes( data:ByteArray ):String
80 var blocks:Array = createBlocksFromByteArray( data );
81 var byteArray:ByteArray = hashBlocks(blocks);
83 return IntUtil.toHex( byteArray.readInt(), true )
84 + IntUtil.toHex( byteArray.readInt(), true )
85 + IntUtil.toHex( byteArray.readInt(), true )
86 + IntUtil.toHex( byteArray.readInt(), true )
87 + IntUtil.toHex( byteArray.readInt(), true )
88 + IntUtil.toHex( byteArray.readInt(), true )
89 + IntUtil.toHex( byteArray.readInt(), true )
90 + IntUtil.toHex( byteArray.readInt(), true );
94 * Performs the SHA256 hash algorithm on a string, then does
95 * Base64 encoding on the result.
97 * @param s The string to hash
98 * @return The base64 encoded hash value of s
99 * @langversion ActionScript 3.0
103 public static function hashToBase64( s:String ):String
105 var blocks:Array = createBlocksFromString( s );
106 var byteArray:ByteArray = hashBlocks(blocks);
108 // ByteArray.toString() returns the contents as a UTF-8 string,
109 // which we can't use because certain byte sequences might trigger
110 // a UTF-8 conversion. Instead, we convert the bytes to characters
112 var charsInByteArray:String = "";
113 byteArray.position = 0;
114 for (var j:int = 0; j < byteArray.length; j++)
116 var byte:uint = byteArray.readUnsignedByte();
117 charsInByteArray += String.fromCharCode(byte);
120 var encoder:Base64Encoder = new Base64Encoder();
121 encoder.encode(charsInByteArray);
122 return encoder.flush();
125 private static function hashBlocks( blocks:Array ):ByteArray {
126 var h0:int = 0x6a09e667;
127 var h1:int = 0xbb67ae85;
128 var h2:int = 0x3c6ef372;
129 var h3:int = 0xa54ff53a;
130 var h4:int = 0x510e527f;
131 var h5:int = 0x9b05688c;
132 var h6:int = 0x1f83d9ab;
133 var h7:int = 0x5be0cd19;
135 var k:Array = new Array(0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070, 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2);
137 var len:int = blocks.length;
138 var w:Array = new Array( 64 );
140 // loop over all of the blocks
141 for ( var i:int = 0; i < len; i += 16 ) {
152 for(var t:int = 0; t < 64; t++) {
155 w[t] = blocks[ i + t ];
156 if(isNaN(w[t])) { w[t] = 0; }
158 var ws0:int = IntUtil.ror(w[t-15], 7) ^ IntUtil.ror(w[t-15], 18) ^ (w[t-15] >>> 3);
159 var ws1:int = IntUtil.ror(w[t-2], 17) ^ IntUtil.ror(w[t-2], 19) ^ (w[t-2] >>> 10);
160 w[t] = w[t-16] + ws0 + w[t-7] + ws1;
163 var s0:int = IntUtil.ror(a, 2) ^ IntUtil.ror(a, 13) ^ IntUtil.ror(a, 22);
164 var maj:int = (a & b) ^ (a & c) ^ (b & c);
165 var t2:int = s0 + maj;
166 var s1:int = IntUtil.ror(e, 6) ^ IntUtil.ror(e, 11) ^ IntUtil.ror(e, 25);
167 var ch:int = (e & f) ^ ((~e) & g);
168 var t1:int = h + s1 + ch + k[t] + w[t];
180 //Add this chunk's hash to result so far:
191 var byteArray:ByteArray = new ByteArray();
192 byteArray.writeInt(h0);
193 byteArray.writeInt(h1);
194 byteArray.writeInt(h2);
195 byteArray.writeInt(h3);
196 byteArray.writeInt(h4);
197 byteArray.writeInt(h5);
198 byteArray.writeInt(h6);
199 byteArray.writeInt(h7);
200 byteArray.position = 0;
202 digest = new ByteArray();
203 digest.writeBytes(byteArray);
209 * Converts a ByteArray to a sequence of 16-word blocks
210 * that we'll do the processing on. Appends padding
211 * and length in the process.
213 * @param data The data to split into blocks
214 * @return An array containing the blocks into which data was split
216 private static function createBlocksFromByteArray( data:ByteArray ):Array
218 var oldPosition:int = data.position;
221 var blocks:Array = new Array();
222 var len:int = data.length * 8;
223 var mask:int = 0xFF; // ignore hi byte of characters > 0xFF
224 for( var i:int = 0; i < len; i += 8 )
226 blocks[ i >> 5 ] |= ( data.readByte() & mask ) << ( 24 - i % 32 );
229 // append padding and length
230 blocks[ len >> 5 ] |= 0x80 << ( 24 - len % 32 );
231 blocks[ ( ( ( len + 64 ) >> 9 ) << 4 ) + 15 ] = len;
233 data.position = oldPosition;
239 * Converts a string to a sequence of 16-word blocks
240 * that we'll do the processing on. Appends padding
241 * and length in the process.
243 * @param s The string to split into blocks
244 * @return An array containing the blocks that s was split into.
246 private static function createBlocksFromString( s:String ):Array
248 var blocks:Array = new Array();
249 var len:int = s.length * 8;
250 var mask:int = 0xFF; // ignore hi byte of characters > 0xFF
251 for( var i:int = 0; i < len; i += 8 ) {
252 blocks[ i >> 5 ] |= ( s.charCodeAt( i / 8 ) & mask ) << ( 24 - i % 32 );
255 // append padding and length
256 blocks[ len >> 5 ] |= 0x80 << ( 24 - len % 32 );
257 blocks[ ( ( ( len + 64 ) >> 9 ) << 4 ) + 15 ] = len;