Improve Camellia code readability.
[openssl.git] / crypto / camellia / cmll_cbc.c
1 /* crypto/camellia/camellia_cbc.c -*- mode:C; c-file-style: "eay" -*- */
2 /* ====================================================================
3  * Copyright (c) 2006 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 CAMELLIA_DEBUG
53 # ifndef NDEBUG
54 #  define NDEBUG
55 # endif
56 #endif
57 #include <assert.h>
58 #include <stdio.h>
59 #include <string.h>
60
61 #include <openssl/camellia.h>
62 #include "cmll_locl.h"
63
64 void Camellia_cbc_encrypt(const unsigned char *in, unsigned char *out,
65                      const unsigned long length, const CAMELLIA_KEY *key,
66                      unsigned char *ivec, const int enc) {
67
68         unsigned long n;
69         unsigned long len = length;
70         unsigned char tmp[CAMELLIA_BLOCK_SIZE];
71         const unsigned char *iv = ivec;
72         u32 t32[CAMELLIA_BLOCK_SIZE/sizeof(u32)];
73         const union { long one; char little; } camellia_endian = {1};
74
75
76         assert(in && out && key && ivec);
77         assert((CAMELLIA_ENCRYPT == enc)||(CAMELLIA_DECRYPT == enc));
78
79         if(((size_t)in|(size_t)out|(size_t)ivec) % sizeof(u32) == 0)
80                 {
81                 if (CAMELLIA_ENCRYPT == enc)
82                         {
83                         while (len >= CAMELLIA_BLOCK_SIZE)
84                                 {
85                                 XOR4WORD2((u32 *)out,
86                                         (u32 *)in, (u32 *)iv);
87                                 if (camellia_endian.little)
88                                         SWAP4WORD((u32 *)out);
89                                 key->enc(key->rd_key, (u32 *)out);
90                                 if (camellia_endian.little)
91                                         SWAP4WORD((u32 *)out);
92                                 iv = out;
93                                 len -= CAMELLIA_BLOCK_SIZE;
94                                 in += CAMELLIA_BLOCK_SIZE;
95                                 out += CAMELLIA_BLOCK_SIZE;
96                                 }
97                         if (len)
98                                 {
99                                 for(n=0; n < len; ++n)
100                                         out[n] = in[n] ^ iv[n];
101                                 for(n=len; n < CAMELLIA_BLOCK_SIZE; ++n)
102                                         out[n] = iv[n];
103                                 if (camellia_endian.little)
104                                         SWAP4WORD((u32 *)out);
105                                 key->enc(key->rd_key, (u32 *)out);
106                                 if (camellia_endian.little)
107                                         SWAP4WORD((u32 *)out);
108                                 iv = out;
109                                 }
110                         memcpy(ivec,iv,CAMELLIA_BLOCK_SIZE);
111                         }
112                 else if (in != out)
113                         {
114                         while (len >= CAMELLIA_BLOCK_SIZE)
115                                 {
116                                 memcpy(out,in,CAMELLIA_BLOCK_SIZE);
117                                 if (camellia_endian.little)
118                                         SWAP4WORD((u32 *)out);
119                                 key->dec(key->rd_key,(u32 *)out);
120                                 if (camellia_endian.little)
121                                         SWAP4WORD((u32 *)out);
122                                 XOR4WORD((u32 *)out, (u32 *)iv);
123                                 iv = in;
124                                 len -= CAMELLIA_BLOCK_SIZE;
125                                 in  += CAMELLIA_BLOCK_SIZE;
126                                 out += CAMELLIA_BLOCK_SIZE;
127                                 }
128                         if (len)
129                                 {
130                                 memcpy(tmp, in, CAMELLIA_BLOCK_SIZE);
131                                 if (camellia_endian.little)
132                                         SWAP4WORD((u32 *)tmp);
133                                 key->dec(key->rd_key, (u32 *)tmp);
134                                 if (camellia_endian.little)
135                                         SWAP4WORD((u32 *)tmp);
136                                 for(n=0; n < len; ++n)
137                                         out[n] = tmp[n] ^ iv[n];
138                                 iv = in;
139                                 }
140                         memcpy(ivec,iv,CAMELLIA_BLOCK_SIZE);
141                         }
142                 else /* in == out */
143                         {
144                         while (len >= CAMELLIA_BLOCK_SIZE)
145                                 {
146                                 memcpy(tmp, in, CAMELLIA_BLOCK_SIZE);
147                                 if (camellia_endian.little)
148                                         SWAP4WORD((u32 *)out);
149                                 key->dec(key->rd_key, (u32 *)out);
150                                 if (camellia_endian.little)
151                                         SWAP4WORD((u32 *)out);
152                                 XOR4WORD((u32 *)out, (u32 *)ivec);
153                                 memcpy(ivec, tmp, CAMELLIA_BLOCK_SIZE);
154                                 len -= CAMELLIA_BLOCK_SIZE;
155                                 in += CAMELLIA_BLOCK_SIZE;
156                                 out += CAMELLIA_BLOCK_SIZE;
157                                 }
158                         if (len)
159                                 {
160                                 memcpy(tmp, in, CAMELLIA_BLOCK_SIZE);
161                                 if (camellia_endian.little)
162                                         SWAP4WORD((u32 *)out);
163                                 key->dec(key->rd_key,(u32 *)out);
164                                 if (camellia_endian.little)
165                                         SWAP4WORD((u32 *)out);
166                                 for(n=0; n < len; ++n)
167                                         out[n] ^= ivec[n];
168                                 for(n=len; n < CAMELLIA_BLOCK_SIZE; ++n)
169                                         out[n] = tmp[n];
170                                 memcpy(ivec, tmp, CAMELLIA_BLOCK_SIZE);
171                                 }
172                         }
173                 }
174         else /* no aligned */
175                 {
176                 if (CAMELLIA_ENCRYPT == enc)
177                         {
178                         while (len >= CAMELLIA_BLOCK_SIZE)
179                                 {
180                                 for(n=0; n < CAMELLIA_BLOCK_SIZE; ++n)
181                                         out[n] = in[n] ^ iv[n];
182                                 memcpy(t32, out, CAMELLIA_BLOCK_SIZE);
183                                 if (camellia_endian.little)
184                                         SWAP4WORD(t32);
185                                 key->enc(key->rd_key, t32);
186                                 if (camellia_endian.little)
187                                         SWAP4WORD(t32);
188                                 memcpy(out, t32, CAMELLIA_BLOCK_SIZE);
189                                 iv = out;
190                                 len -= CAMELLIA_BLOCK_SIZE;
191                                 in += CAMELLIA_BLOCK_SIZE;
192                                 out += CAMELLIA_BLOCK_SIZE;
193                                 }
194                         if (len)
195                                 {
196                                 for(n=0; n < len; ++n)
197                                         out[n] = in[n] ^ iv[n];
198                                 for(n=len; n < CAMELLIA_BLOCK_SIZE; ++n)
199                                         out[n] = iv[n];
200                                 memcpy(t32, out, CAMELLIA_BLOCK_SIZE);
201                                 if (camellia_endian.little)
202                                         SWAP4WORD(t32);
203                                 key->enc(key->rd_key, t32);
204                                 if (camellia_endian.little)
205                                         SWAP4WORD(t32);
206                                 memcpy(out, t32, CAMELLIA_BLOCK_SIZE);
207                                 iv = out;
208                                 }
209                         memcpy(ivec,iv,CAMELLIA_BLOCK_SIZE);
210                         }
211                 else if (in != out)
212                         {
213                         while (len >= CAMELLIA_BLOCK_SIZE)
214                                 {
215                                 memcpy(t32,in,CAMELLIA_BLOCK_SIZE);
216                                 if (camellia_endian.little)
217                                         SWAP4WORD(t32);
218                                 key->dec(key->rd_key,t32);
219                                 if (camellia_endian.little)
220                                         SWAP4WORD(t32);
221                                 memcpy(out,t32,CAMELLIA_BLOCK_SIZE);
222                                 for(n=0; n < CAMELLIA_BLOCK_SIZE; ++n)
223                                         out[n] ^= iv[n];
224                                 iv = in;
225                                 len -= CAMELLIA_BLOCK_SIZE;
226                                 in  += CAMELLIA_BLOCK_SIZE;
227                                 out += CAMELLIA_BLOCK_SIZE;
228                                 }
229                         if (len)
230                                 {
231                                 memcpy(t32, in, CAMELLIA_BLOCK_SIZE);
232                                 if (camellia_endian.little)
233                                         SWAP4WORD(t32);
234                                 key->dec(key->rd_key, t32);
235                                 if (camellia_endian.little)
236                                         SWAP4WORD(t32);
237                                 memcpy(out, t32, CAMELLIA_BLOCK_SIZE);
238                                 for(n=0; n < len; ++n)
239                                         out[n] ^= iv[n];
240                                 iv = in;
241                                 }
242                         memcpy(ivec,iv,CAMELLIA_BLOCK_SIZE);
243                         }
244                 else
245                         {
246                         while (len >= CAMELLIA_BLOCK_SIZE)
247                                 {
248                                 memcpy(tmp, in, CAMELLIA_BLOCK_SIZE);
249                                 memcpy(t32, in, CAMELLIA_BLOCK_SIZE);
250                                 if (camellia_endian.little)
251                                         SWAP4WORD(t32);
252                                 key->dec(key->rd_key, t32);
253                                 if (camellia_endian.little)
254                                         SWAP4WORD(t32);
255                                 memcpy(out, t32, CAMELLIA_BLOCK_SIZE);
256                                 for(n=0; n < CAMELLIA_BLOCK_SIZE; ++n)
257                                         out[n] ^= ivec[n];
258                                 memcpy(ivec, tmp, CAMELLIA_BLOCK_SIZE);
259                                 len -= CAMELLIA_BLOCK_SIZE;
260                                 in += CAMELLIA_BLOCK_SIZE;
261                                 out += CAMELLIA_BLOCK_SIZE;
262                                 }
263                         if (len)
264                                 {
265                                 memcpy(tmp, in, CAMELLIA_BLOCK_SIZE);
266                                 memcpy(t32, in, CAMELLIA_BLOCK_SIZE);
267                                 if (camellia_endian.little)
268                                         SWAP4WORD(t32);
269                                 key->dec(key->rd_key,t32);
270                                 if (camellia_endian.little)
271                                         SWAP4WORD(t32);
272                                 memcpy(out, t32, CAMELLIA_BLOCK_SIZE);
273                                 for(n=0; n < len; ++n)
274                                         out[n] ^= ivec[n];
275                                 for(n=len; n < CAMELLIA_BLOCK_SIZE; ++n)
276                                         out[n] = tmp[n];
277                                 memcpy(ivec, tmp, CAMELLIA_BLOCK_SIZE);
278                                 }
279                         }
280                 }
281 }