1 /* crypto/aes/aes_cbc.c -*- mode:C; c-file-style: "eay" -*- */
2 /* ====================================================================
3 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
31 * 6. Redistributions of any form whatsoever must retain the following
33 * "This product includes software developed by the OpenSSL Project
34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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 * ====================================================================
59 #include <openssl/aes.h>
62 #if !defined(OPENSSL_FIPS_AES_ASM)
63 void 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) {
68 unsigned long len = length;
69 unsigned char tmp[AES_BLOCK_SIZE];
70 const unsigned char *iv = ivec;
72 assert(in && out && key && ivec);
73 assert((AES_ENCRYPT == enc)||(AES_DECRYPT == enc));
75 if (AES_ENCRYPT == enc) {
76 while (len >= AES_BLOCK_SIZE) {
77 for(n=0; n < AES_BLOCK_SIZE; ++n)
78 out[n] = in[n] ^ iv[n];
79 AES_encrypt(out, out, key);
81 len -= AES_BLOCK_SIZE;
83 out += AES_BLOCK_SIZE;
86 for(n=0; n < len; ++n)
87 out[n] = in[n] ^ iv[n];
88 for(n=len; n < AES_BLOCK_SIZE; ++n)
90 AES_encrypt(out, out, key);
93 memcpy(ivec,iv,AES_BLOCK_SIZE);
94 } else if (in != out) {
95 while (len >= AES_BLOCK_SIZE) {
96 AES_decrypt(in, out, key);
97 for(n=0; n < AES_BLOCK_SIZE; ++n)
100 len -= AES_BLOCK_SIZE;
101 in += AES_BLOCK_SIZE;
102 out += AES_BLOCK_SIZE;
105 AES_decrypt(in,tmp,key);
106 for(n=0; n < len; ++n)
107 out[n] = tmp[n] ^ iv[n];
110 memcpy(ivec,iv,AES_BLOCK_SIZE);
112 while (len >= AES_BLOCK_SIZE) {
113 memcpy(tmp, in, AES_BLOCK_SIZE);
114 AES_decrypt(in, out, key);
115 for(n=0; n < AES_BLOCK_SIZE; ++n)
117 memcpy(ivec, tmp, AES_BLOCK_SIZE);
118 len -= AES_BLOCK_SIZE;
119 in += AES_BLOCK_SIZE;
120 out += AES_BLOCK_SIZE;
123 memcpy(tmp, in, AES_BLOCK_SIZE);
124 AES_decrypt(tmp, out, key);
125 for(n=0; n < len; ++n)
127 for(n=len; n < AES_BLOCK_SIZE; ++n)
129 memcpy(ivec, tmp, AES_BLOCK_SIZE);