Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 1 | /* crypto/aes/aes_ige.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 | #include "cryptlib.h" |
| 53 | |
| 54 | #include <openssl/aes.h> |
| 55 | #include "aes_locl.h" |
| 56 | |
| 57 | #define N_WORDS (AES_BLOCK_SIZE / sizeof(unsigned long)) |
| 58 | typedef struct { |
| 59 | unsigned long data[N_WORDS]; |
| 60 | } aes_block_t; |
| 61 | |
| 62 | /* XXX: probably some better way to do this */ |
| 63 | #if defined(__i386__) || defined(__x86_64__) |
| 64 | #define UNALIGNED_MEMOPS_ARE_FAST 1 |
| 65 | #else |
| 66 | #define UNALIGNED_MEMOPS_ARE_FAST 0 |
| 67 | #endif |
| 68 | |
| 69 | #if UNALIGNED_MEMOPS_ARE_FAST |
| 70 | #define load_block(d, s) (d) = *(const aes_block_t *)(s) |
| 71 | #define store_block(d, s) *(aes_block_t *)(d) = (s) |
| 72 | #else |
| 73 | #define load_block(d, s) memcpy((d).data, (s), AES_BLOCK_SIZE) |
| 74 | #define store_block(d, s) memcpy((d), (s).data, AES_BLOCK_SIZE) |
| 75 | #endif |
| 76 | |
| 77 | /* N.B. The IV for this mode is _twice_ the block size */ |
| 78 | |
| 79 | void AES_ige_encrypt(const unsigned char *in, unsigned char *out, |
| 80 | size_t length, const AES_KEY *key, |
| 81 | unsigned char *ivec, const int enc) |
| 82 | { |
| 83 | size_t n; |
| 84 | size_t len = length; |
| 85 | |
| 86 | OPENSSL_assert(in && out && key && ivec); |
| 87 | OPENSSL_assert((AES_ENCRYPT == enc)||(AES_DECRYPT == enc)); |
| 88 | OPENSSL_assert((length%AES_BLOCK_SIZE) == 0); |
| 89 | |
| 90 | len = length / AES_BLOCK_SIZE; |
| 91 | |
| 92 | if (AES_ENCRYPT == enc) |
| 93 | { |
| 94 | if (in != out && |
| 95 | (UNALIGNED_MEMOPS_ARE_FAST || ((size_t)in|(size_t)out|(size_t)ivec)%sizeof(long)==0)) |
| 96 | { |
| 97 | aes_block_t *ivp = (aes_block_t *)ivec; |
| 98 | aes_block_t *iv2p = (aes_block_t *)(ivec + AES_BLOCK_SIZE); |
| 99 | |
| 100 | while (len) |
| 101 | { |
| 102 | aes_block_t *inp = (aes_block_t *)in; |
| 103 | aes_block_t *outp = (aes_block_t *)out; |
| 104 | |
| 105 | for(n=0 ; n < N_WORDS; ++n) |
| 106 | outp->data[n] = inp->data[n] ^ ivp->data[n]; |
| 107 | AES_encrypt((unsigned char *)outp->data, (unsigned char *)outp->data, key); |
| 108 | for(n=0 ; n < N_WORDS; ++n) |
| 109 | outp->data[n] ^= iv2p->data[n]; |
| 110 | ivp = outp; |
| 111 | iv2p = inp; |
| 112 | --len; |
| 113 | in += AES_BLOCK_SIZE; |
| 114 | out += AES_BLOCK_SIZE; |
| 115 | } |
| 116 | memcpy(ivec, ivp->data, AES_BLOCK_SIZE); |
| 117 | memcpy(ivec + AES_BLOCK_SIZE, iv2p->data, AES_BLOCK_SIZE); |
| 118 | } |
| 119 | else |
| 120 | { |
| 121 | aes_block_t tmp, tmp2; |
| 122 | aes_block_t iv; |
| 123 | aes_block_t iv2; |
| 124 | |
| 125 | load_block(iv, ivec); |
| 126 | load_block(iv2, ivec + AES_BLOCK_SIZE); |
| 127 | |
| 128 | while (len) |
| 129 | { |
| 130 | load_block(tmp, in); |
| 131 | for(n=0 ; n < N_WORDS; ++n) |
| 132 | tmp2.data[n] = tmp.data[n] ^ iv.data[n]; |
| 133 | AES_encrypt((unsigned char *)tmp2.data, (unsigned char *)tmp2.data, key); |
| 134 | for(n=0 ; n < N_WORDS; ++n) |
| 135 | tmp2.data[n] ^= iv2.data[n]; |
| 136 | store_block(out, tmp2); |
| 137 | iv = tmp2; |
| 138 | iv2 = tmp; |
| 139 | --len; |
| 140 | in += AES_BLOCK_SIZE; |
| 141 | out += AES_BLOCK_SIZE; |
| 142 | } |
| 143 | memcpy(ivec, iv.data, AES_BLOCK_SIZE); |
| 144 | memcpy(ivec + AES_BLOCK_SIZE, iv2.data, AES_BLOCK_SIZE); |
| 145 | } |
| 146 | } |
| 147 | else |
| 148 | { |
| 149 | if (in != out && |
| 150 | (UNALIGNED_MEMOPS_ARE_FAST || ((size_t)in|(size_t)out|(size_t)ivec)%sizeof(long)==0)) |
| 151 | { |
| 152 | aes_block_t *ivp = (aes_block_t *)ivec; |
| 153 | aes_block_t *iv2p = (aes_block_t *)(ivec + AES_BLOCK_SIZE); |
| 154 | |
| 155 | while (len) |
| 156 | { |
| 157 | aes_block_t tmp; |
| 158 | aes_block_t *inp = (aes_block_t *)in; |
| 159 | aes_block_t *outp = (aes_block_t *)out; |
| 160 | |
| 161 | for(n=0 ; n < N_WORDS; ++n) |
| 162 | tmp.data[n] = inp->data[n] ^ iv2p->data[n]; |
| 163 | AES_decrypt((unsigned char *)tmp.data, (unsigned char *)outp->data, key); |
| 164 | for(n=0 ; n < N_WORDS; ++n) |
| 165 | outp->data[n] ^= ivp->data[n]; |
| 166 | ivp = inp; |
| 167 | iv2p = outp; |
| 168 | --len; |
| 169 | in += AES_BLOCK_SIZE; |
| 170 | out += AES_BLOCK_SIZE; |
| 171 | } |
| 172 | memcpy(ivec, ivp->data, AES_BLOCK_SIZE); |
| 173 | memcpy(ivec + AES_BLOCK_SIZE, iv2p->data, AES_BLOCK_SIZE); |
| 174 | } |
| 175 | else |
| 176 | { |
| 177 | aes_block_t tmp, tmp2; |
| 178 | aes_block_t iv; |
| 179 | aes_block_t iv2; |
| 180 | |
| 181 | load_block(iv, ivec); |
| 182 | load_block(iv2, ivec + AES_BLOCK_SIZE); |
| 183 | |
| 184 | while (len) |
| 185 | { |
| 186 | load_block(tmp, in); |
| 187 | tmp2 = tmp; |
| 188 | for(n=0 ; n < N_WORDS; ++n) |
| 189 | tmp.data[n] ^= iv2.data[n]; |
| 190 | AES_decrypt((unsigned char *)tmp.data, (unsigned char *)tmp.data, key); |
| 191 | for(n=0 ; n < N_WORDS; ++n) |
| 192 | tmp.data[n] ^= iv.data[n]; |
| 193 | store_block(out, tmp); |
| 194 | iv = tmp2; |
| 195 | iv2 = tmp; |
| 196 | --len; |
| 197 | in += AES_BLOCK_SIZE; |
| 198 | out += AES_BLOCK_SIZE; |
| 199 | } |
| 200 | memcpy(ivec, iv.data, AES_BLOCK_SIZE); |
| 201 | memcpy(ivec + AES_BLOCK_SIZE, iv2.data, AES_BLOCK_SIZE); |
| 202 | } |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | /* |
| 207 | * Note that its effectively impossible to do biIGE in anything other |
| 208 | * than a single pass, so no provision is made for chaining. |
| 209 | */ |
| 210 | |
| 211 | /* N.B. The IV for this mode is _four times_ the block size */ |
| 212 | |
| 213 | void AES_bi_ige_encrypt(const unsigned char *in, unsigned char *out, |
| 214 | size_t length, const AES_KEY *key, |
| 215 | const AES_KEY *key2, const unsigned char *ivec, |
| 216 | const int enc) |
| 217 | { |
| 218 | size_t n; |
| 219 | size_t len = length; |
| 220 | unsigned char tmp[AES_BLOCK_SIZE]; |
| 221 | unsigned char tmp2[AES_BLOCK_SIZE]; |
| 222 | unsigned char tmp3[AES_BLOCK_SIZE]; |
| 223 | unsigned char prev[AES_BLOCK_SIZE]; |
| 224 | const unsigned char *iv; |
| 225 | const unsigned char *iv2; |
| 226 | |
| 227 | OPENSSL_assert(in && out && key && ivec); |
| 228 | OPENSSL_assert((AES_ENCRYPT == enc)||(AES_DECRYPT == enc)); |
| 229 | OPENSSL_assert((length%AES_BLOCK_SIZE) == 0); |
| 230 | |
| 231 | if (AES_ENCRYPT == enc) |
| 232 | { |
| 233 | /* XXX: Do a separate case for when in != out (strictly should |
| 234 | check for overlap, too) */ |
| 235 | |
| 236 | /* First the forward pass */ |
| 237 | iv = ivec; |
| 238 | iv2 = ivec + AES_BLOCK_SIZE; |
| 239 | while (len >= AES_BLOCK_SIZE) |
| 240 | { |
| 241 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 242 | out[n] = in[n] ^ iv[n]; |
| 243 | AES_encrypt(out, out, key); |
| 244 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 245 | out[n] ^= iv2[n]; |
| 246 | iv = out; |
| 247 | memcpy(prev, in, AES_BLOCK_SIZE); |
| 248 | iv2 = prev; |
| 249 | len -= AES_BLOCK_SIZE; |
| 250 | in += AES_BLOCK_SIZE; |
| 251 | out += AES_BLOCK_SIZE; |
| 252 | } |
| 253 | |
| 254 | /* And now backwards */ |
| 255 | iv = ivec + AES_BLOCK_SIZE*2; |
| 256 | iv2 = ivec + AES_BLOCK_SIZE*3; |
| 257 | len = length; |
| 258 | while(len >= AES_BLOCK_SIZE) |
| 259 | { |
| 260 | out -= AES_BLOCK_SIZE; |
| 261 | /* XXX: reduce copies by alternating between buffers */ |
| 262 | memcpy(tmp, out, AES_BLOCK_SIZE); |
| 263 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 264 | out[n] ^= iv[n]; |
| 265 | /* hexdump(stdout, "out ^ iv", out, AES_BLOCK_SIZE); */ |
| 266 | AES_encrypt(out, out, key); |
| 267 | /* hexdump(stdout,"enc", out, AES_BLOCK_SIZE); */ |
| 268 | /* hexdump(stdout,"iv2", iv2, AES_BLOCK_SIZE); */ |
| 269 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 270 | out[n] ^= iv2[n]; |
| 271 | /* hexdump(stdout,"out", out, AES_BLOCK_SIZE); */ |
| 272 | iv = out; |
| 273 | memcpy(prev, tmp, AES_BLOCK_SIZE); |
| 274 | iv2 = prev; |
| 275 | len -= AES_BLOCK_SIZE; |
| 276 | } |
| 277 | } |
| 278 | else |
| 279 | { |
| 280 | /* First backwards */ |
| 281 | iv = ivec + AES_BLOCK_SIZE*2; |
| 282 | iv2 = ivec + AES_BLOCK_SIZE*3; |
| 283 | in += length; |
| 284 | out += length; |
| 285 | while (len >= AES_BLOCK_SIZE) |
| 286 | { |
| 287 | in -= AES_BLOCK_SIZE; |
| 288 | out -= AES_BLOCK_SIZE; |
| 289 | memcpy(tmp, in, AES_BLOCK_SIZE); |
| 290 | memcpy(tmp2, in, AES_BLOCK_SIZE); |
| 291 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 292 | tmp[n] ^= iv2[n]; |
| 293 | AES_decrypt(tmp, out, key); |
| 294 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 295 | out[n] ^= iv[n]; |
| 296 | memcpy(tmp3, tmp2, AES_BLOCK_SIZE); |
| 297 | iv = tmp3; |
| 298 | iv2 = out; |
| 299 | len -= AES_BLOCK_SIZE; |
| 300 | } |
| 301 | |
| 302 | /* And now forwards */ |
| 303 | iv = ivec; |
| 304 | iv2 = ivec + AES_BLOCK_SIZE; |
| 305 | len = length; |
| 306 | while (len >= AES_BLOCK_SIZE) |
| 307 | { |
| 308 | memcpy(tmp, out, AES_BLOCK_SIZE); |
| 309 | memcpy(tmp2, out, AES_BLOCK_SIZE); |
| 310 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 311 | tmp[n] ^= iv2[n]; |
| 312 | AES_decrypt(tmp, out, key); |
| 313 | for(n=0 ; n < AES_BLOCK_SIZE ; ++n) |
| 314 | out[n] ^= iv[n]; |
| 315 | memcpy(tmp3, tmp2, AES_BLOCK_SIZE); |
| 316 | iv = tmp3; |
| 317 | iv2 = out; |
| 318 | len -= AES_BLOCK_SIZE; |
| 319 | in += AES_BLOCK_SIZE; |
| 320 | out += AES_BLOCK_SIZE; |
| 321 | } |
| 322 | } |
| 323 | } |