1/*
2 * Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include "internal/cryptlib.h"
11
12#ifdef OPENSSL_NO_DEPRECATED_3_0
13NON_EMPTY_TRANSLATION_UNIT
14#else
15
16#include <openssl/aes.h>
17#include "aes_local.h"
18
19#define N_WORDS (AES_BLOCK_SIZE / sizeof(unsigned long))
20typedef struct {
21 unsigned long data[N_WORDS];
22} aes_block_t;
23
24/* XXX: probably some better way to do this */
25#if defined(__i386__) || defined(__x86_64__)
26# define UNALIGNED_MEMOPS_ARE_FAST 1
27#else
28# define UNALIGNED_MEMOPS_ARE_FAST 0
29#endif
30
31#if UNALIGNED_MEMOPS_ARE_FAST
32# define load_block(d, s) (d) = *(const aes_block_t *)(s)
33# define store_block(d, s) *(aes_block_t *)(d) = (s)
34#else
35# define load_block(d, s) memcpy((d).data, (s), AES_BLOCK_SIZE)
36# define store_block(d, s) memcpy((d), (s).data, AES_BLOCK_SIZE)
37#endif
38
39/* N.B. The IV for this mode is _twice_ the block size */
40
41/* Use of this function is deprecated. */
42void AES_ige_encrypt(const unsigned char *in, unsigned char *out,
43 size_t length, const AES_KEY *key,
44 unsigned char *ivec, const int enc)
45{
46 size_t n;
47 size_t len = length;
48
49 if (length == 0)
50 return;
51
52 OPENSSL_assert(in && out && key && ivec);
53 OPENSSL_assert((AES_ENCRYPT == enc) || (AES_DECRYPT == enc));
54 OPENSSL_assert((length % AES_BLOCK_SIZE) == 0);
55
56 len = length / AES_BLOCK_SIZE;
57
58 if (AES_ENCRYPT == enc) {
59 if (in != out &&
60 (UNALIGNED_MEMOPS_ARE_FAST
61 || ((size_t)in | (size_t)out | (size_t)ivec) % sizeof(long) ==
62 0)) {
63 aes_block_t *ivp = (aes_block_t *) ivec;
64 aes_block_t *iv2p = (aes_block_t *) (ivec + AES_BLOCK_SIZE);
65
66 while (len) {
67 aes_block_t *inp = (aes_block_t *) in;
68 aes_block_t *outp = (aes_block_t *) out;
69
70 for (n = 0; n < N_WORDS; ++n)
71 outp->data[n] = inp->data[n] ^ ivp->data[n];
72 AES_encrypt((unsigned char *)outp->data,
73 (unsigned char *)outp->data, key);
74 for (n = 0; n < N_WORDS; ++n)
75 outp->data[n] ^= iv2p->data[n];
76 ivp = outp;
77 iv2p = inp;
78 --len;
79 in += AES_BLOCK_SIZE;
80 out += AES_BLOCK_SIZE;
81 }
82 memcpy(ivec, ivp->data, AES_BLOCK_SIZE);
83 memcpy(ivec + AES_BLOCK_SIZE, iv2p->data, AES_BLOCK_SIZE);
84 } else {
85 aes_block_t tmp, tmp2;
86 aes_block_t iv;
87 aes_block_t iv2;
88
89 load_block(iv, ivec);
90 load_block(iv2, ivec + AES_BLOCK_SIZE);
91
92 while (len) {
93 load_block(tmp, in);
94 for (n = 0; n < N_WORDS; ++n)
95 tmp2.data[n] = tmp.data[n] ^ iv.data[n];
96 AES_encrypt((unsigned char *)tmp2.data,
97 (unsigned char *)tmp2.data, key);
98 for (n = 0; n < N_WORDS; ++n)
99 tmp2.data[n] ^= iv2.data[n];
100 store_block(out, tmp2);
101 iv = tmp2;
102 iv2 = tmp;
103 --len;
104 in += AES_BLOCK_SIZE;
105 out += AES_BLOCK_SIZE;
106 }
107 memcpy(ivec, iv.data, AES_BLOCK_SIZE);
108 memcpy(ivec + AES_BLOCK_SIZE, iv2.data, AES_BLOCK_SIZE);
109 }
110 } else {
111 if (in != out &&
112 (UNALIGNED_MEMOPS_ARE_FAST
113 || ((size_t)in | (size_t)out | (size_t)ivec) % sizeof(long) ==
114 0)) {
115 aes_block_t *ivp = (aes_block_t *) ivec;
116 aes_block_t *iv2p = (aes_block_t *) (ivec + AES_BLOCK_SIZE);
117
118 while (len) {
119 aes_block_t tmp;
120 aes_block_t *inp = (aes_block_t *) in;
121 aes_block_t *outp = (aes_block_t *) out;
122
123 for (n = 0; n < N_WORDS; ++n)
124 tmp.data[n] = inp->data[n] ^ iv2p->data[n];
125 AES_decrypt((unsigned char *)tmp.data,
126 (unsigned char *)outp->data, key);
127 for (n = 0; n < N_WORDS; ++n)
128 outp->data[n] ^= ivp->data[n];
129 ivp = inp;
130 iv2p = outp;
131 --len;
132 in += AES_BLOCK_SIZE;
133 out += AES_BLOCK_SIZE;
134 }
135 memcpy(ivec, ivp->data, AES_BLOCK_SIZE);
136 memcpy(ivec + AES_BLOCK_SIZE, iv2p->data, AES_BLOCK_SIZE);
137 } else {
138 aes_block_t tmp, tmp2;
139 aes_block_t iv;
140 aes_block_t iv2;
141
142 load_block(iv, ivec);
143 load_block(iv2, ivec + AES_BLOCK_SIZE);
144
145 while (len) {
146 load_block(tmp, in);
147 tmp2 = tmp;
148 for (n = 0; n < N_WORDS; ++n)
149 tmp.data[n] ^= iv2.data[n];
150 AES_decrypt((unsigned char *)tmp.data,
151 (unsigned char *)tmp.data, key);
152 for (n = 0; n < N_WORDS; ++n)
153 tmp.data[n] ^= iv.data[n];
154 store_block(out, tmp);
155 iv = tmp2;
156 iv2 = tmp;
157 --len;
158 in += AES_BLOCK_SIZE;
159 out += AES_BLOCK_SIZE;
160 }
161 memcpy(ivec, iv.data, AES_BLOCK_SIZE);
162 memcpy(ivec + AES_BLOCK_SIZE, iv2.data, AES_BLOCK_SIZE);
163 }
164 }
165}
166
167/*
168 * Note that its effectively impossible to do biIGE in anything other
169 * than a single pass, so no provision is made for chaining.
170 *
171 * NB: The implementation of AES_bi_ige_encrypt has a bug. It is supposed to use
172 * 2 AES keys, but in fact only one is ever used. This bug has been present
173 * since this code was first implemented. It is believed to have minimal
174 * security impact in practice and has therefore not been fixed for backwards
175 * compatibility reasons.
176 *
177 * Use of this function is deprecated.
178 */
179
180/* N.B. The IV for this mode is _four times_ the block size */
181
182void AES_bi_ige_encrypt(const unsigned char *in, unsigned char *out,
183 size_t length, const AES_KEY *key,
184 const AES_KEY *key2, const unsigned char *ivec,
185 const int enc)
186{
187 size_t n;
188 size_t len = length;
189 unsigned char tmp[AES_BLOCK_SIZE];
190 unsigned char tmp2[AES_BLOCK_SIZE];
191 unsigned char tmp3[AES_BLOCK_SIZE];
192 unsigned char prev[AES_BLOCK_SIZE];
193 const unsigned char *iv;
194 const unsigned char *iv2;
195
196 OPENSSL_assert(in && out && key && ivec);
197 OPENSSL_assert((AES_ENCRYPT == enc) || (AES_DECRYPT == enc));
198 OPENSSL_assert((length % AES_BLOCK_SIZE) == 0);
199
200 if (AES_ENCRYPT == enc) {
201 /*
202 * XXX: Do a separate case for when in != out (strictly should check
203 * for overlap, too)
204 */
205
206 /* First the forward pass */
207 iv = ivec;
208 iv2 = ivec + AES_BLOCK_SIZE;
209 while (len >= AES_BLOCK_SIZE) {
210 for (n = 0; n < AES_BLOCK_SIZE; ++n)
211 out[n] = in[n] ^ iv[n];
212 AES_encrypt(out, out, key);
213 for (n = 0; n < AES_BLOCK_SIZE; ++n)
214 out[n] ^= iv2[n];
215 iv = out;
216 memcpy(prev, in, AES_BLOCK_SIZE);
217 iv2 = prev;
218 len -= AES_BLOCK_SIZE;
219 in += AES_BLOCK_SIZE;
220 out += AES_BLOCK_SIZE;
221 }
222
223 /* And now backwards */
224 iv = ivec + AES_BLOCK_SIZE * 2;
225 iv2 = ivec + AES_BLOCK_SIZE * 3;
226 len = length;
227 while (len >= AES_BLOCK_SIZE) {
228 out -= AES_BLOCK_SIZE;
229 /*
230 * XXX: reduce copies by alternating between buffers
231 */
232 memcpy(tmp, out, AES_BLOCK_SIZE);
233 for (n = 0; n < AES_BLOCK_SIZE; ++n)
234 out[n] ^= iv[n];
235 /*
236 * hexdump(stdout, "out ^ iv", out, AES_BLOCK_SIZE);
237 */
238 AES_encrypt(out, out, key);
239 /*
240 * hexdump(stdout,"enc", out, AES_BLOCK_SIZE);
241 */
242 /*
243 * hexdump(stdout,"iv2", iv2, AES_BLOCK_SIZE);
244 */
245 for (n = 0; n < AES_BLOCK_SIZE; ++n)
246 out[n] ^= iv2[n];
247 /*
248 * hexdump(stdout,"out", out, AES_BLOCK_SIZE);
249 */
250 iv = out;
251 memcpy(prev, tmp, AES_BLOCK_SIZE);
252 iv2 = prev;
253 len -= AES_BLOCK_SIZE;
254 }
255 } else {
256 /* First backwards */
257 iv = ivec + AES_BLOCK_SIZE * 2;
258 iv2 = ivec + AES_BLOCK_SIZE * 3;
259 in += length;
260 out += length;
261 while (len >= AES_BLOCK_SIZE) {
262 in -= AES_BLOCK_SIZE;
263 out -= AES_BLOCK_SIZE;
264 memcpy(tmp, in, AES_BLOCK_SIZE);
265 memcpy(tmp2, in, AES_BLOCK_SIZE);
266 for (n = 0; n < AES_BLOCK_SIZE; ++n)
267 tmp[n] ^= iv2[n];
268 AES_decrypt(tmp, out, key);
269 for (n = 0; n < AES_BLOCK_SIZE; ++n)
270 out[n] ^= iv[n];
271 memcpy(tmp3, tmp2, AES_BLOCK_SIZE);
272 iv = tmp3;
273 iv2 = out;
274 len -= AES_BLOCK_SIZE;
275 }
276
277 /* And now forwards */
278 iv = ivec;
279 iv2 = ivec + AES_BLOCK_SIZE;
280 len = length;
281 while (len >= AES_BLOCK_SIZE) {
282 memcpy(tmp, out, AES_BLOCK_SIZE);
283 memcpy(tmp2, out, AES_BLOCK_SIZE);
284 for (n = 0; n < AES_BLOCK_SIZE; ++n)
285 tmp[n] ^= iv2[n];
286 AES_decrypt(tmp, out, key);
287 for (n = 0; n < AES_BLOCK_SIZE; ++n)
288 out[n] ^= iv[n];
289 memcpy(tmp3, tmp2, AES_BLOCK_SIZE);
290 iv = tmp3;
291 iv2 = out;
292 len -= AES_BLOCK_SIZE;
293 in += AES_BLOCK_SIZE;
294 out += AES_BLOCK_SIZE;
295 }
296 }
297}
298#endif
299