1 /* $OpenBSD: cbc128.c,v 1.4 2015/02/10 09:46:30 miod Exp $ */ 2 /* ==================================================================== 3 * Copyright (c) 2008 The OpenSSL Project. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in 14 * the documentation and/or other materials provided with the 15 * distribution. 16 * 17 * 3. All advertising materials mentioning features or use of this 18 * software must display the following acknowledgment: 19 * "This product includes software developed by the OpenSSL Project 20 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 21 * 22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 23 * endorse or promote products derived from this software without 24 * prior written permission. For written permission, please contact 25 * openssl-core@openssl.org. 26 * 27 * 5. Products derived from this software may not be called "OpenSSL" 28 * nor may "OpenSSL" appear in their names without prior written 29 * permission of the OpenSSL Project. 30 * 31 * 6. Redistributions of any form whatsoever must retain the following 32 * acknowledgment: 33 * "This product includes software developed by the OpenSSL Project 34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 35 * 36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 39 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 47 * OF THE POSSIBILITY OF SUCH DAMAGE. 48 * ==================================================================== 49 * 50 */ 51 52 #include <openssl/crypto.h> 53 #include "modes_lcl.h" 54 #include <string.h> 55 56 #ifndef MODES_DEBUG 57 # ifndef NDEBUG 58 # define NDEBUG 59 # endif 60 #endif 61 62 #undef STRICT_ALIGNMENT 63 #ifdef __STRICT_ALIGNMENT 64 #define STRICT_ALIGNMENT 1 65 #else 66 #define STRICT_ALIGNMENT 0 67 #endif 68 69 void CRYPTO_cbc128_encrypt(const unsigned char *in, unsigned char *out, 70 size_t len, const void *key, 71 unsigned char ivec[16], block128_f block) 72 { 73 size_t n; 74 const unsigned char *iv = ivec; 75 76 #if !defined(OPENSSL_SMALL_FOOTPRINT) 77 if (STRICT_ALIGNMENT && 78 ((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) { 79 while (len>=16) { 80 for(n=0; n<16; ++n) 81 out[n] = in[n] ^ iv[n]; 82 (*block)(out, out, key); 83 iv = out; 84 len -= 16; 85 in += 16; 86 out += 16; 87 } 88 } else { 89 while (len>=16) { 90 for(n=0; n<16; n+=sizeof(size_t)) 91 *(size_t*)(out+n) = 92 *(size_t*)(in+n) ^ *(size_t*)(iv+n); 93 (*block)(out, out, key); 94 iv = out; 95 len -= 16; 96 in += 16; 97 out += 16; 98 } 99 } 100 #endif 101 while (len) { 102 for(n=0; n<16 && n<len; ++n) 103 out[n] = in[n] ^ iv[n]; 104 for(; n<16; ++n) 105 out[n] = iv[n]; 106 (*block)(out, out, key); 107 iv = out; 108 if (len<=16) break; 109 len -= 16; 110 in += 16; 111 out += 16; 112 } 113 memcpy(ivec,iv,16); 114 } 115 116 void 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 { size_t t[16/sizeof(size_t)]; unsigned char c[16]; } tmp; 122 123 #if !defined(OPENSSL_SMALL_FOOTPRINT) 124 if (in != out) { 125 const unsigned char *iv = ivec; 126 127 if (STRICT_ALIGNMENT && 128 ((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) { 129 while (len>=16) { 130 (*block)(in, out, key); 131 for(n=0; n<16; ++n) 132 out[n] ^= iv[n]; 133 iv = in; 134 len -= 16; 135 in += 16; 136 out += 16; 137 } 138 } else if (16%sizeof(size_t) == 0) { /* always true */ 139 while (len>=16) { 140 size_t *out_t=(size_t *)out, *iv_t=(size_t *)iv; 141 142 (*block)(in, out, key); 143 for(n=0; n<16/sizeof(size_t); n++) 144 out_t[n] ^= iv_t[n]; 145 iv = in; 146 len -= 16; 147 in += 16; 148 out += 16; 149 } 150 } 151 memcpy(ivec,iv,16); 152 } else { 153 if (STRICT_ALIGNMENT && 154 ((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) { 155 unsigned char c; 156 while (len>=16) { 157 (*block)(in, tmp.c, key); 158 for(n=0; n<16; ++n) { 159 c = in[n]; 160 out[n] = tmp.c[n] ^ ivec[n]; 161 ivec[n] = c; 162 } 163 len -= 16; 164 in += 16; 165 out += 16; 166 } 167 } else if (16%sizeof(size_t) == 0) { /* always true */ 168 while (len>=16) { 169 size_t c, *out_t=(size_t *)out, *ivec_t=(size_t *)ivec; 170 const size_t *in_t=(const size_t *)in; 171 172 (*block)(in, tmp.c, key); 173 for(n=0; n<16/sizeof(size_t); n++) { 174 c = in_t[n]; 175 out_t[n] = tmp.t[n] ^ ivec_t[n]; 176 ivec_t[n] = c; 177 } 178 len -= 16; 179 in += 16; 180 out += 16; 181 } 182 } 183 } 184 #endif 185 while (len) { 186 unsigned char c; 187 (*block)(in, tmp.c, key); 188 for(n=0; n<16 && n<len; ++n) { 189 c = in[n]; 190 out[n] = tmp.c[n] ^ ivec[n]; 191 ivec[n] = c; 192 } 193 if (len<=16) { 194 for (; n<16; ++n) 195 ivec[n] = in[n]; 196 break; 197 } 198 len -= 16; 199 in += 16; 200 out += 16; 201 } 202 } 203