1/* crc.c - Cyclic redundancy checks. 2 * Copyright (C) 2003 Free Software Foundation, Inc. 3 * 4 * This file is part of Libgcrypt. 5 * 6 * Libgcrypt is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU Lesser General Public License as 8 * published by the Free Software Foundation; either version 2.1 of 9 * the License, or (at your option) any later version. 10 * 11 * Libgcrypt is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA 19 * 20 */ 21 22#include <config.h> 23#include <stdio.h> 24#include <stdlib.h> 25#include <string.h> 26 27#include "g10lib.h" 28#include "cipher.h" 29 30#include "bithelp.h" 31 32/* Table of CRCs of all 8-bit messages. Generated by running code 33 from RFC 1952 modified to print out the table. */ 34static u32 crc32_table[256] = { 35 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 36 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 37 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 38 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 39 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 40 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 41 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 42 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 43 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 44 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 45 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 46 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 47 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 48 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 49 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 50 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 51 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 52 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 53 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 54 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 55 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 56 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 57 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 58 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 59 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 60 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 61 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 62 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 63 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 64 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 65 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 66 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 67 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 68 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 69 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 70 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 71 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 72 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 73 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 74 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 75 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 76 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 77 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d 78}; 79 80/* 81 * The following function was extracted from RFC 1952 by Simon 82 * Josefsson, for the Shishi project, and modified to be compatible 83 * with the modified CRC-32 used by RFC 1510, and subsequently 84 * modified for GNU Libgcrypt to allow it to be used for calculating 85 * both unmodified CRC-32 and modified CRC-32 values. Original 86 * copyright and notice from the document follows: 87 * 88 * Copyright (c) 1996 L. Peter Deutsch 89 * 90 * Permission is granted to copy and distribute this document for 91 * any purpose and without charge, including translations into 92 * other languages and incorporation into compilations, provided 93 * that the copyright notice and this notice are preserved, and 94 * that any substantive changes or deletions from the original are 95 * clearly marked. 96 * 97 * The copyright on RFCs, and consequently the function below, are 98 * supposedly also retroactively claimed by the Internet Society 99 * (according to rfc-editor@rfc-editor.org), with the following 100 * copyright notice: 101 * 102 * Copyright (C) The Internet Society. All Rights Reserved. 103 * 104 * This document and translations of it may be copied and furnished 105 * to others, and derivative works that comment on or otherwise 106 * explain it or assist in its implementation may be prepared, 107 * copied, published and distributed, in whole or in part, without 108 * restriction of any kind, provided that the above copyright 109 * notice and this paragraph are included on all such copies and 110 * derivative works. However, this document itself may not be 111 * modified in any way, such as by removing the copyright notice or 112 * references to the Internet Society or other Internet 113 * organizations, except as needed for the purpose of developing 114 * Internet standards in which case the procedures for copyrights 115 * defined in the Internet Standards process must be followed, or 116 * as required to translate it into languages other than English. 117 * 118 * The limited permissions granted above are perpetual and will not be 119 * revoked by the Internet Society or its successors or assigns. 120 * 121 * This document and the information contained herein is provided 122 * on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET 123 * ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR 124 * IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE 125 * OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY 126 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A 127 * PARTICULAR PURPOSE. 128 * 129 */ 130static u32 131update_crc32 (u32 crc, const void *buf_arg, size_t len) 132{ 133 const char *buf = buf_arg; 134 size_t n; 135 136 for (n = 0; n < len; n++) 137 crc = crc32_table[(crc ^ buf[n]) & 0xff] ^ (crc >> 8); 138 139 return crc; 140} 141 142typedef struct 143{ 144 u32 CRC; 145 byte buf[4]; 146} 147CRC_CONTEXT; 148 149/* CRC32 */ 150 151static void 152crc32_init (void *context) 153{ 154 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 155 ctx->CRC = 0 ^ 0xffffffffL; 156} 157 158static void 159crc32_write (void *context, const void *inbuf, size_t inlen) 160{ 161 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 162 if (!inbuf) 163 return; 164 ctx->CRC = update_crc32 (ctx->CRC, inbuf, inlen); 165} 166 167static byte * 168crc32_read (void *context) 169{ 170 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 171 return ctx->buf; 172} 173 174static void 175crc32_final (void *context) 176{ 177 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 178 ctx->CRC ^= 0xffffffffL; 179 ctx->buf[0] = (ctx->CRC >> 24) & 0xFF; 180 ctx->buf[1] = (ctx->CRC >> 16) & 0xFF; 181 ctx->buf[2] = (ctx->CRC >> 8) & 0xFF; 182 ctx->buf[3] = (ctx->CRC ) & 0xFF; 183} 184 185/* CRC32 a'la RFC 1510 */ 186static void 187crc32rfc1510_init (void *context) 188{ 189 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 190 ctx->CRC = 0; 191} 192 193static void 194crc32rfc1510_final (void *context) 195{ 196 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 197 ctx->buf[0] = (ctx->CRC >> 24) & 0xFF; 198 ctx->buf[1] = (ctx->CRC >> 16) & 0xFF; 199 ctx->buf[2] = (ctx->CRC >> 8) & 0xFF; 200 ctx->buf[3] = (ctx->CRC ) & 0xFF; 201} 202 203/* CRC24 a'la RFC 2440 */ 204/* 205 * The following CRC 24 routines are adapted from RFC 2440, which has 206 * the following copyright notice: 207 * 208 * Copyright (C) The Internet Society (1998). All Rights Reserved. 209 * 210 * This document and translations of it may be copied and furnished 211 * to others, and derivative works that comment on or otherwise 212 * explain it or assist in its implementation may be prepared, 213 * copied, published and distributed, in whole or in part, without 214 * restriction of any kind, provided that the above copyright notice 215 * and this paragraph are included on all such copies and derivative 216 * works. However, this document itself may not be modified in any 217 * way, such as by removing the copyright notice or references to 218 * the Internet Society or other Internet organizations, except as 219 * needed for the purpose of developing Internet standards in which 220 * case the procedures for copyrights defined in the Internet 221 * Standards process must be followed, or as required to translate 222 * it into languages other than English. 223 * 224 * The limited permissions granted above are perpetual and will not be 225 * revoked by the Internet Society or its successors or assigns. 226 * 227 * This document and the information contained herein is provided on 228 * an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET 229 * ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR 230 * IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE 231 * OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY 232 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR 233 * PURPOSE. 234 */ 235 236#define CRC24_INIT 0xb704ceL 237#define CRC24_POLY 0x1864cfbL 238 239static void 240crc24rfc2440_init (void *context) 241{ 242 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 243 ctx->CRC = CRC24_INIT; 244} 245 246static void 247crc24rfc2440_write (void *context, const void *inbuf_arg, size_t inlen) 248{ 249 const unsigned char *inbuf = inbuf_arg; 250 int i; 251 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 252 253 if (!inbuf) 254 return; 255 256 while (inlen--) { 257 ctx->CRC ^= (*inbuf++) << 16; 258 for (i = 0; i < 8; i++) { 259 ctx->CRC <<= 1; 260 if (ctx->CRC & 0x1000000) 261 ctx->CRC ^= CRC24_POLY; 262 } 263 } 264} 265 266static void 267crc24rfc2440_final (void *context) 268{ 269 CRC_CONTEXT *ctx = (CRC_CONTEXT *) context; 270 ctx->buf[0] = (ctx->CRC >> 16) & 0xFF; 271 ctx->buf[1] = (ctx->CRC >> 8) & 0xFF; 272 ctx->buf[2] = (ctx->CRC ) & 0xFF; 273} 274 275gcry_md_spec_t _gcry_digest_spec_crc32 = 276 { 277 "CRC32", NULL, 0, NULL, 4, 278 crc32_init, crc32_write, crc32_final, crc32_read, 279 sizeof (CRC_CONTEXT) 280 }; 281 282gcry_md_spec_t _gcry_digest_spec_crc32_rfc1510 = 283 { 284 "CRC32RFC1510", NULL, 0, NULL, 4, 285 crc32rfc1510_init, crc32_write, 286 crc32rfc1510_final, crc32_read, 287 sizeof (CRC_CONTEXT) 288 }; 289 290gcry_md_spec_t _gcry_digest_spec_crc24_rfc2440 = 291 { 292 "CRC24RFC2440", NULL, 0, NULL, 3, 293 crc24rfc2440_init, crc24rfc2440_write, 294 crc24rfc2440_final, crc32_read, 295 sizeof (CRC_CONTEXT) 296 }; 297