aes_cbc.c revision 296465
1/* crypto/aes/aes_cbc.c -*- mode:C; c-file-style: "eay" -*- */ 2/* ==================================================================== 3 * Copyright (c) 1998-2002 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#ifndef AES_DEBUG 53# ifndef NDEBUG 54# define NDEBUG 55# endif 56#endif 57#include <assert.h> 58 59#include <openssl/aes.h> 60#include "aes_locl.h" 61 62#if !defined(OPENSSL_FIPS_AES_ASM) 63void AES_cbc_encrypt(const unsigned char *in, unsigned char *out, 64 const unsigned long length, const AES_KEY *key, 65 unsigned char *ivec, const int enc) 66{ 67 68 unsigned long n; 69 unsigned long len = length; 70 unsigned char tmp[AES_BLOCK_SIZE]; 71 const unsigned char *iv = ivec; 72 73 assert(in && out && key && ivec); 74 assert((AES_ENCRYPT == enc) || (AES_DECRYPT == enc)); 75 76 if (AES_ENCRYPT == enc) { 77 while (len >= AES_BLOCK_SIZE) { 78 for (n = 0; n < AES_BLOCK_SIZE; ++n) 79 out[n] = in[n] ^ iv[n]; 80 AES_encrypt(out, out, key); 81 iv = out; 82 len -= AES_BLOCK_SIZE; 83 in += AES_BLOCK_SIZE; 84 out += AES_BLOCK_SIZE; 85 } 86 if (len) { 87 for (n = 0; n < len; ++n) 88 out[n] = in[n] ^ iv[n]; 89 for (n = len; n < AES_BLOCK_SIZE; ++n) 90 out[n] = iv[n]; 91 AES_encrypt(out, out, key); 92 iv = out; 93 } 94 memcpy(ivec, iv, AES_BLOCK_SIZE); 95 } else if (in != out) { 96 while (len >= AES_BLOCK_SIZE) { 97 AES_decrypt(in, out, key); 98 for (n = 0; n < AES_BLOCK_SIZE; ++n) 99 out[n] ^= iv[n]; 100 iv = in; 101 len -= AES_BLOCK_SIZE; 102 in += AES_BLOCK_SIZE; 103 out += AES_BLOCK_SIZE; 104 } 105 if (len) { 106 AES_decrypt(in, tmp, key); 107 for (n = 0; n < len; ++n) 108 out[n] = tmp[n] ^ iv[n]; 109 iv = in; 110 } 111 memcpy(ivec, iv, AES_BLOCK_SIZE); 112 } else { 113 while (len >= AES_BLOCK_SIZE) { 114 memcpy(tmp, in, AES_BLOCK_SIZE); 115 AES_decrypt(in, out, key); 116 for (n = 0; n < AES_BLOCK_SIZE; ++n) 117 out[n] ^= ivec[n]; 118 memcpy(ivec, tmp, AES_BLOCK_SIZE); 119 len -= AES_BLOCK_SIZE; 120 in += AES_BLOCK_SIZE; 121 out += AES_BLOCK_SIZE; 122 } 123 if (len) { 124 memcpy(tmp, in, AES_BLOCK_SIZE); 125 AES_decrypt(tmp, out, key); 126 for (n = 0; n < len; ++n) 127 out[n] ^= ivec[n]; 128 for (n = len; n < AES_BLOCK_SIZE; ++n) 129 out[n] = tmp[n]; 130 memcpy(ivec, tmp, AES_BLOCK_SIZE); 131 } 132 } 133} 134#endif 135