Botan  1.11.15
src/lib/hash/checksum/crc32/crc32.cpp
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00001 /*
00002 * CRC32
00003 * (C) 1999-2007 Jack Lloyd
00004 *
00005 * Botan is released under the Simplified BSD License (see license.txt)
00006 */
00007 
00008 #include <botan/internal/hash_utils.h>
00009 #include <botan/crc32.h>
00010 
00011 namespace Botan {
00012 
00013 BOTAN_REGISTER_HASH_NOARGS(CRC32);
00014 
00015 /*
00016 * Update a CRC32 Checksum
00017 */
00018 void CRC32::add_data(const byte input[], size_t length)
00019    {
00020    const u32bit TABLE[256] = {
00021       0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F,
00022       0xE963A535, 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,
00023       0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2,
00024       0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
00025       0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9,
00026       0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,
00027       0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C,
00028       0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
00029       0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423,
00030       0xCFBA9599, 0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
00031       0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190, 0x01DB7106,
00032       0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
00033       0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D,
00034       0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,
00035       0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950,
00036       0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
00037       0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7,
00038       0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,
00039       0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA,
00040       0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
00041       0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81,
00042       0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,
00043       0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 0xE3630B12, 0x94643B84,
00044       0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
00045       0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB,
00046       0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
00047       0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E,
00048       0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
00049       0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55,
00050       0x316E8EEF, 0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
00051       0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE, 0xB2BD0B28,
00052       0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
00053       0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F,
00054       0x72076785, 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,
00055       0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242,
00056       0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
00057       0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69,
00058       0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,
00059       0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC,
00060       0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
00061       0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693,
00062       0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
00063       0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D };
00064 
00065    u32bit tmp = crc;
00066    while(length >= 16)
00067       {
00068       tmp = TABLE[(tmp ^ input[ 0]) & 0xFF] ^ (tmp >> 8);
00069       tmp = TABLE[(tmp ^ input[ 1]) & 0xFF] ^ (tmp >> 8);
00070       tmp = TABLE[(tmp ^ input[ 2]) & 0xFF] ^ (tmp >> 8);
00071       tmp = TABLE[(tmp ^ input[ 3]) & 0xFF] ^ (tmp >> 8);
00072       tmp = TABLE[(tmp ^ input[ 4]) & 0xFF] ^ (tmp >> 8);
00073       tmp = TABLE[(tmp ^ input[ 5]) & 0xFF] ^ (tmp >> 8);
00074       tmp = TABLE[(tmp ^ input[ 6]) & 0xFF] ^ (tmp >> 8);
00075       tmp = TABLE[(tmp ^ input[ 7]) & 0xFF] ^ (tmp >> 8);
00076       tmp = TABLE[(tmp ^ input[ 8]) & 0xFF] ^ (tmp >> 8);
00077       tmp = TABLE[(tmp ^ input[ 9]) & 0xFF] ^ (tmp >> 8);
00078       tmp = TABLE[(tmp ^ input[10]) & 0xFF] ^ (tmp >> 8);
00079       tmp = TABLE[(tmp ^ input[11]) & 0xFF] ^ (tmp >> 8);
00080       tmp = TABLE[(tmp ^ input[12]) & 0xFF] ^ (tmp >> 8);
00081       tmp = TABLE[(tmp ^ input[13]) & 0xFF] ^ (tmp >> 8);
00082       tmp = TABLE[(tmp ^ input[14]) & 0xFF] ^ (tmp >> 8);
00083       tmp = TABLE[(tmp ^ input[15]) & 0xFF] ^ (tmp >> 8);
00084       input += 16;
00085       length -= 16;
00086       }
00087 
00088    for(size_t i = 0; i != length; ++i)
00089       tmp = TABLE[(tmp ^ input[i]) & 0xFF] ^ (tmp >> 8);
00090 
00091    crc = tmp;
00092    }
00093 
00094 /*
00095 * Finalize a CRC32 Checksum
00096 */
00097 void CRC32::final_result(byte output[])
00098    {
00099    crc ^= 0xFFFFFFFF;
00100    store_be(crc, output);
00101    clear();
00102    }
00103 
00104 }