cbc128.c revision 296341
1/* ==================================================================== 2 * Copyright (c) 2008 The OpenSSL Project. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in 13 * the documentation and/or other materials provided with the 14 * distribution. 15 * 16 * 3. All advertising materials mentioning features or use of this 17 * software must display the following acknowledgment: 18 * "This product includes software developed by the OpenSSL Project 19 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 20 * 21 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 22 * endorse or promote products derived from this software without 23 * prior written permission. For written permission, please contact 24 * openssl-core@openssl.org. 25 * 26 * 5. Products derived from this software may not be called "OpenSSL" 27 * nor may "OpenSSL" appear in their names without prior written 28 * permission of the OpenSSL Project. 29 * 30 * 6. Redistributions of any form whatsoever must retain the following 31 * acknowledgment: 32 * "This product includes software developed by the OpenSSL Project 33 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 34 * 35 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 36 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 38 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 42 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 44 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 45 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 46 * OF THE POSSIBILITY OF SUCH DAMAGE. 47 * ==================================================================== 48 * 49 */ 50 51#include <openssl/crypto.h> 52#include "modes_lcl.h" 53#include <string.h> 54 55#ifndef MODES_DEBUG 56# ifndef NDEBUG 57# define NDEBUG 58# endif 59#endif 60#include <assert.h> 61 62#ifndef STRICT_ALIGNMENT 63# define STRICT_ALIGNMENT 0 64#endif 65 66void CRYPTO_cbc128_encrypt(const unsigned char *in, unsigned char *out, 67 size_t len, const void *key, 68 unsigned char ivec[16], block128_f block) 69{ 70 size_t n; 71 const unsigned char *iv = ivec; 72 73 assert(in && out && key && ivec); 74 75#if !defined(OPENSSL_SMALL_FOOTPRINT) 76 if (STRICT_ALIGNMENT && 77 ((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) { 78 while (len >= 16) { 79 for (n = 0; n < 16; ++n) 80 out[n] = in[n] ^ iv[n]; 81 (*block) (out, out, key); 82 iv = out; 83 len -= 16; 84 in += 16; 85 out += 16; 86 } 87 } else { 88 while (len >= 16) { 89 for (n = 0; n < 16; n += sizeof(size_t)) 90 *(size_t *)(out + n) = 91 *(size_t *)(in + n) ^ *(size_t *)(iv + n); 92 (*block) (out, out, key); 93 iv = out; 94 len -= 16; 95 in += 16; 96 out += 16; 97 } 98 } 99#endif 100 while (len) { 101 for (n = 0; n < 16 && n < len; ++n) 102 out[n] = in[n] ^ iv[n]; 103 for (; n < 16; ++n) 104 out[n] = iv[n]; 105 (*block) (out, out, key); 106 iv = out; 107 if (len <= 16) 108 break; 109 len -= 16; 110 in += 16; 111 out += 16; 112 } 113 memcpy(ivec, iv, 16); 114} 115 116void CRYPTO_cbc128_decrypt(const unsigned char *in, unsigned char *out, 117 size_t len, const void *key, 118 unsigned char ivec[16], block128_f block) 119{ 120 size_t n; 121 union { 122 size_t t[16 / sizeof(size_t)]; 123 unsigned char c[16]; 124 } tmp; 125 126 assert(in && out && key && ivec); 127 128#if !defined(OPENSSL_SMALL_FOOTPRINT) 129 if (in != out) { 130 const unsigned char *iv = ivec; 131 132 if (STRICT_ALIGNMENT && 133 ((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) { 134 while (len >= 16) { 135 (*block) (in, out, key); 136 for (n = 0; n < 16; ++n) 137 out[n] ^= iv[n]; 138 iv = in; 139 len -= 16; 140 in += 16; 141 out += 16; 142 } 143 } else if (16 % sizeof(size_t) == 0) { /* always true */ 144 while (len >= 16) { 145 size_t *out_t = (size_t *)out, *iv_t = (size_t *)iv; 146 147 (*block) (in, out, key); 148 for (n = 0; n < 16 / sizeof(size_t); n++) 149 out_t[n] ^= iv_t[n]; 150 iv = in; 151 len -= 16; 152 in += 16; 153 out += 16; 154 } 155 } 156 memcpy(ivec, iv, 16); 157 } else { 158 if (STRICT_ALIGNMENT && 159 ((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) { 160 unsigned char c; 161 while (len >= 16) { 162 (*block) (in, tmp.c, key); 163 for (n = 0; n < 16; ++n) { 164 c = in[n]; 165 out[n] = tmp.c[n] ^ ivec[n]; 166 ivec[n] = c; 167 } 168 len -= 16; 169 in += 16; 170 out += 16; 171 } 172 } else if (16 % sizeof(size_t) == 0) { /* always true */ 173 while (len >= 16) { 174 size_t c, *out_t = (size_t *)out, *ivec_t = (size_t *)ivec; 175 const size_t *in_t = (const size_t *)in; 176 177 (*block) (in, tmp.c, key); 178 for (n = 0; n < 16 / sizeof(size_t); n++) { 179 c = in_t[n]; 180 out_t[n] = tmp.t[n] ^ ivec_t[n]; 181 ivec_t[n] = c; 182 } 183 len -= 16; 184 in += 16; 185 out += 16; 186 } 187 } 188 } 189#endif 190 while (len) { 191 unsigned char c; 192 (*block) (in, tmp.c, key); 193 for (n = 0; n < 16 && n < len; ++n) { 194 c = in[n]; 195 out[n] = tmp.c[n] ^ ivec[n]; 196 ivec[n] = c; 197 } 198 if (len <= 16) { 199 for (; n < 16; ++n) 200 ivec[n] = in[n]; 201 break; 202 } 203 len -= 16; 204 in += 16; 205 out += 16; 206 } 207} 208