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
66 void 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) break;
108 len -= 16;
109 in += 16;
110 out += 16;
111 }
112 memcpy(ivec,iv,16);
113 }
114
115 void CRYPTO_cbc128_decrypt(const unsigned char *in, unsigned char *out,
116 size_t len, const void *key,
117 unsigned char ivec[16], block128_f block)
118 {
119 size_t n;
120 union { size_t t[16/sizeof(size_t)]; unsigned char c[16]; } tmp;
121
122 assert(in && out && key && ivec);
123
124 #if !defined(OPENSSL_SMALL_FOOTPRINT)
125 if (in != out) {
126 const unsigned char *iv = ivec;
127
128 if (STRICT_ALIGNMENT &&
129 ((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) {
130 while (len>=16) {
131 (*block)(in, out, key);
132 for(n=0; n<16; ++n)
133 out[n] ^= iv[n];
134 iv = in;
135 len -= 16;
136 in += 16;
137 out += 16;
138 }
139 }
140 else if (16%sizeof(size_t) == 0) { /* always true */
141 while (len>=16) {
142 size_t *out_t=(size_t *)out, *iv_t=(size_t *)iv;
143
144 (*block)(in, out, key);
145 for(n=0; n<16/sizeof(size_t); n++)
146 out_t[n] ^= iv_t[n];
147 iv = in;
148 len -= 16;
149 in += 16;
150 out += 16;
151 }
152 }
153 memcpy(ivec,iv,16);
154 } else {
155 if (STRICT_ALIGNMENT &&
156 ((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) {
157 unsigned char c;
158 while (len>=16) {
159 (*block)(in, tmp.c, key);
160 for(n=0; n<16; ++n) {
161 c = in[n];
162 out[n] = tmp.c[n] ^ ivec[n];
163 ivec[n] = c;
164 }
165 len -= 16;
166 in += 16;
167 out += 16;
168 }
169 }
170 else if (16%sizeof(size_t) == 0) { /* always true */
171 while (len>=16) {
172 size_t c, *out_t=(size_t *)out, *ivec_t=(size_t *)ivec;
173 const size_t *in_t=(const size_t *)in;
174
175 (*block)(in, tmp.c, key);
176 for(n=0; n<16/sizeof(size_t); n++) {
177 c = in_t[n];
178 out_t[n] = tmp.t[n] ^ ivec_t[n];
179 ivec_t[n] = c;
180 }
181 len -= 16;
182 in += 16;
183 out += 16;
184 }
185 }
186 }
187 #endif
188 while (len) {
189 unsigned char c;
190 (*block)(in, tmp.c, key);
191 for(n=0; n<16 && n<len; ++n) {
192 c = in[n];
193 out[n] = tmp.c[n] ^ ivec[n];
194 ivec[n] = c;
195 }
196 if (len<=16) {
197 for (; n<16; ++n)
198 ivec[n] = in[n];
199 break;
200 }
201 len -= 16;
202 in += 16;
203 out += 16;
204 }
205 }