Tristan Matthews | 0a329cc | 2013-07-17 13:20:14 -0400 | [diff] [blame] | 1 | /* |
| 2 | * cipher.c |
| 3 | * |
| 4 | * cipher meta-functions |
| 5 | * |
| 6 | * David A. McGrew |
| 7 | * Cisco Systems, Inc. |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | /* |
| 12 | * |
| 13 | * Copyright (c) 2001-2006, Cisco Systems, Inc. |
| 14 | * All rights reserved. |
| 15 | * |
| 16 | * Redistribution and use in source and binary forms, with or without |
| 17 | * modification, are permitted provided that the following conditions |
| 18 | * are met: |
| 19 | * |
| 20 | * Redistributions of source code must retain the above copyright |
| 21 | * notice, this list of conditions and the following disclaimer. |
| 22 | * |
| 23 | * Redistributions in binary form must reproduce the above |
| 24 | * copyright notice, this list of conditions and the following |
| 25 | * disclaimer in the documentation and/or other materials provided |
| 26 | * with the distribution. |
| 27 | * |
| 28 | * Neither the name of the Cisco Systems, Inc. nor the names of its |
| 29 | * contributors may be used to endorse or promote products derived |
| 30 | * from this software without specific prior written permission. |
| 31 | * |
| 32 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 33 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 34 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 35 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 36 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
| 37 | * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| 38 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| 39 | * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 40 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| 41 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 42 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| 43 | * OF THE POSSIBILITY OF SUCH DAMAGE. |
| 44 | * |
| 45 | */ |
| 46 | |
| 47 | #include "cipher.h" |
| 48 | #include "rand_source.h" /* used in invertibiltiy tests */ |
| 49 | #include "alloc.h" /* for crypto_alloc(), crypto_free() */ |
| 50 | |
| 51 | debug_module_t mod_cipher = { |
| 52 | 0, /* debugging is off by default */ |
| 53 | "cipher" /* printable module name */ |
| 54 | }; |
| 55 | |
| 56 | err_status_t |
| 57 | cipher_output(cipher_t *c, uint8_t *buffer, int num_octets_to_output) { |
| 58 | |
| 59 | /* zeroize the buffer */ |
| 60 | octet_string_set_to_zero(buffer, num_octets_to_output); |
| 61 | |
| 62 | /* exor keystream into buffer */ |
| 63 | return cipher_encrypt(c, buffer, (unsigned int *) &num_octets_to_output); |
| 64 | } |
| 65 | |
| 66 | /* some bookkeeping functions */ |
| 67 | |
| 68 | int |
| 69 | cipher_get_key_length(const cipher_t *c) { |
| 70 | return c->key_len; |
| 71 | } |
| 72 | |
| 73 | /* |
| 74 | * cipher_type_self_test(ct) tests a cipher of type ct against test cases |
| 75 | * provided in an array of values of key, salt, xtd_seq_num_t, |
| 76 | * plaintext, and ciphertext that is known to be good |
| 77 | */ |
| 78 | |
| 79 | #define SELF_TEST_BUF_OCTETS 128 |
| 80 | #define NUM_RAND_TESTS 128 |
| 81 | #define MAX_KEY_LEN 64 |
| 82 | |
| 83 | err_status_t |
| 84 | cipher_type_self_test(const cipher_type_t *ct) { |
| 85 | const cipher_test_case_t *test_case = ct->test_data; |
| 86 | cipher_t *c; |
| 87 | err_status_t status; |
| 88 | uint8_t buffer[SELF_TEST_BUF_OCTETS]; |
| 89 | uint8_t buffer2[SELF_TEST_BUF_OCTETS]; |
| 90 | unsigned int len; |
| 91 | int i, j, case_num = 0; |
| 92 | |
| 93 | debug_print(mod_cipher, "running self-test for cipher %s", |
| 94 | ct->description); |
| 95 | |
| 96 | /* |
| 97 | * check to make sure that we have at least one test case, and |
| 98 | * return an error if we don't - we need to be paranoid here |
| 99 | */ |
| 100 | if (test_case == NULL) |
| 101 | return err_status_cant_check; |
| 102 | |
| 103 | /* |
| 104 | * loop over all test cases, perform known-answer tests of both the |
| 105 | * encryption and decryption functions |
| 106 | */ |
| 107 | while (test_case != NULL) { |
| 108 | |
| 109 | /* allocate cipher */ |
| 110 | status = cipher_type_alloc(ct, &c, test_case->key_length_octets); |
| 111 | if (status) |
| 112 | return status; |
| 113 | |
| 114 | /* |
| 115 | * test the encrypt function |
| 116 | */ |
| 117 | debug_print(mod_cipher, "testing encryption", NULL); |
| 118 | |
| 119 | /* initialize cipher */ |
| 120 | status = cipher_init(c, test_case->key, direction_encrypt); |
| 121 | if (status) { |
| 122 | cipher_dealloc(c); |
| 123 | return status; |
| 124 | } |
| 125 | |
| 126 | /* copy plaintext into test buffer */ |
| 127 | if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) { |
| 128 | cipher_dealloc(c); |
| 129 | return err_status_bad_param; |
| 130 | } |
| 131 | for (i=0; i < test_case->plaintext_length_octets; i++) |
| 132 | buffer[i] = test_case->plaintext[i]; |
| 133 | |
| 134 | debug_print(mod_cipher, "plaintext: %s", |
| 135 | octet_string_hex_string(buffer, |
| 136 | test_case->plaintext_length_octets)); |
| 137 | |
| 138 | /* set the initialization vector */ |
| 139 | status = cipher_set_iv(c, test_case->idx); |
| 140 | if (status) { |
| 141 | cipher_dealloc(c); |
| 142 | return status; |
| 143 | } |
| 144 | |
| 145 | /* encrypt */ |
| 146 | len = test_case->plaintext_length_octets; |
| 147 | status = cipher_encrypt(c, buffer, &len); |
| 148 | if (status) { |
| 149 | cipher_dealloc(c); |
| 150 | return status; |
| 151 | } |
| 152 | |
| 153 | debug_print(mod_cipher, "ciphertext: %s", |
| 154 | octet_string_hex_string(buffer, |
| 155 | test_case->ciphertext_length_octets)); |
| 156 | |
| 157 | /* compare the resulting ciphertext with that in the test case */ |
| 158 | if (len != test_case->ciphertext_length_octets) |
| 159 | return err_status_algo_fail; |
| 160 | status = err_status_ok; |
| 161 | for (i=0; i < test_case->ciphertext_length_octets; i++) |
| 162 | if (buffer[i] != test_case->ciphertext[i]) { |
| 163 | status = err_status_algo_fail; |
| 164 | debug_print(mod_cipher, "test case %d failed", case_num); |
| 165 | debug_print(mod_cipher, "(failure at byte %d)", i); |
| 166 | break; |
| 167 | } |
| 168 | if (status) { |
| 169 | |
| 170 | debug_print(mod_cipher, "c computed: %s", |
| 171 | octet_string_hex_string(buffer, |
| 172 | 2*test_case->plaintext_length_octets)); |
| 173 | debug_print(mod_cipher, "c expected: %s", |
| 174 | octet_string_hex_string(test_case->ciphertext, |
| 175 | 2*test_case->plaintext_length_octets)); |
| 176 | |
| 177 | cipher_dealloc(c); |
| 178 | return err_status_algo_fail; |
| 179 | } |
| 180 | |
| 181 | /* |
| 182 | * test the decrypt function |
| 183 | */ |
| 184 | debug_print(mod_cipher, "testing decryption", NULL); |
| 185 | |
| 186 | /* re-initialize cipher for decryption */ |
| 187 | status = cipher_init(c, test_case->key, direction_decrypt); |
| 188 | if (status) { |
| 189 | cipher_dealloc(c); |
| 190 | return status; |
| 191 | } |
| 192 | |
| 193 | /* copy ciphertext into test buffer */ |
| 194 | if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) { |
| 195 | cipher_dealloc(c); |
| 196 | return err_status_bad_param; |
| 197 | } |
| 198 | for (i=0; i < test_case->ciphertext_length_octets; i++) |
| 199 | buffer[i] = test_case->ciphertext[i]; |
| 200 | |
| 201 | debug_print(mod_cipher, "ciphertext: %s", |
| 202 | octet_string_hex_string(buffer, |
| 203 | test_case->plaintext_length_octets)); |
| 204 | |
| 205 | /* set the initialization vector */ |
| 206 | status = cipher_set_iv(c, test_case->idx); |
| 207 | if (status) { |
| 208 | cipher_dealloc(c); |
| 209 | return status; |
| 210 | } |
| 211 | |
| 212 | /* decrypt */ |
| 213 | len = test_case->ciphertext_length_octets; |
| 214 | status = cipher_decrypt(c, buffer, &len); |
| 215 | if (status) { |
| 216 | cipher_dealloc(c); |
| 217 | return status; |
| 218 | } |
| 219 | |
| 220 | debug_print(mod_cipher, "plaintext: %s", |
| 221 | octet_string_hex_string(buffer, |
| 222 | test_case->plaintext_length_octets)); |
| 223 | |
| 224 | /* compare the resulting plaintext with that in the test case */ |
| 225 | if (len != test_case->plaintext_length_octets) |
| 226 | return err_status_algo_fail; |
| 227 | status = err_status_ok; |
| 228 | for (i=0; i < test_case->plaintext_length_octets; i++) |
| 229 | if (buffer[i] != test_case->plaintext[i]) { |
| 230 | status = err_status_algo_fail; |
| 231 | debug_print(mod_cipher, "test case %d failed", case_num); |
| 232 | debug_print(mod_cipher, "(failure at byte %d)", i); |
| 233 | } |
| 234 | if (status) { |
| 235 | |
| 236 | debug_print(mod_cipher, "p computed: %s", |
| 237 | octet_string_hex_string(buffer, |
| 238 | 2*test_case->plaintext_length_octets)); |
| 239 | debug_print(mod_cipher, "p expected: %s", |
| 240 | octet_string_hex_string(test_case->plaintext, |
| 241 | 2*test_case->plaintext_length_octets)); |
| 242 | |
| 243 | cipher_dealloc(c); |
| 244 | return err_status_algo_fail; |
| 245 | } |
| 246 | |
| 247 | /* deallocate the cipher */ |
| 248 | status = cipher_dealloc(c); |
| 249 | if (status) |
| 250 | return status; |
| 251 | |
| 252 | /* |
| 253 | * the cipher passed the test case, so move on to the next test |
| 254 | * case in the list; if NULL, we'l proceed to the next test |
| 255 | */ |
| 256 | test_case = test_case->next_test_case; |
| 257 | ++case_num; |
| 258 | } |
| 259 | |
| 260 | /* now run some random invertibility tests */ |
| 261 | |
| 262 | /* allocate cipher, using paramaters from the first test case */ |
| 263 | test_case = ct->test_data; |
| 264 | status = cipher_type_alloc(ct, &c, test_case->key_length_octets); |
| 265 | if (status) |
| 266 | return status; |
| 267 | |
| 268 | rand_source_init(); |
| 269 | |
| 270 | for (j=0; j < NUM_RAND_TESTS; j++) { |
| 271 | unsigned length; |
| 272 | unsigned plaintext_len; |
| 273 | uint8_t key[MAX_KEY_LEN]; |
| 274 | uint8_t iv[MAX_KEY_LEN]; |
| 275 | |
| 276 | /* choose a length at random (leaving room for IV and padding) */ |
| 277 | length = rand() % (SELF_TEST_BUF_OCTETS - 64); |
| 278 | debug_print(mod_cipher, "random plaintext length %d\n", length); |
| 279 | status = rand_source_get_octet_string(buffer, length); |
| 280 | if (status) return status; |
| 281 | |
| 282 | debug_print(mod_cipher, "plaintext: %s", |
| 283 | octet_string_hex_string(buffer, length)); |
| 284 | |
| 285 | /* copy plaintext into second buffer */ |
| 286 | for (i=0; (unsigned int)i < length; i++) |
| 287 | buffer2[i] = buffer[i]; |
| 288 | |
| 289 | /* choose a key at random */ |
| 290 | if (test_case->key_length_octets > MAX_KEY_LEN) |
| 291 | return err_status_cant_check; |
| 292 | status = rand_source_get_octet_string(key, test_case->key_length_octets); |
| 293 | if (status) return status; |
| 294 | |
| 295 | /* chose a random initialization vector */ |
| 296 | status = rand_source_get_octet_string(iv, MAX_KEY_LEN); |
| 297 | if (status) return status; |
| 298 | |
| 299 | /* initialize cipher */ |
| 300 | status = cipher_init(c, key, direction_encrypt); |
| 301 | if (status) { |
| 302 | cipher_dealloc(c); |
| 303 | return status; |
| 304 | } |
| 305 | |
| 306 | /* set initialization vector */ |
| 307 | status = cipher_set_iv(c, test_case->idx); |
| 308 | if (status) { |
| 309 | cipher_dealloc(c); |
| 310 | return status; |
| 311 | } |
| 312 | |
| 313 | /* encrypt buffer with cipher */ |
| 314 | plaintext_len = length; |
| 315 | status = cipher_encrypt(c, buffer, &length); |
| 316 | if (status) { |
| 317 | cipher_dealloc(c); |
| 318 | return status; |
| 319 | } |
| 320 | debug_print(mod_cipher, "ciphertext: %s", |
| 321 | octet_string_hex_string(buffer, length)); |
| 322 | |
| 323 | /* |
| 324 | * re-initialize cipher for decryption, re-set the iv, then |
| 325 | * decrypt the ciphertext |
| 326 | */ |
| 327 | status = cipher_init(c, key, direction_decrypt); |
| 328 | if (status) { |
| 329 | cipher_dealloc(c); |
| 330 | return status; |
| 331 | } |
| 332 | status = cipher_set_iv(c, test_case->idx); |
| 333 | if (status) { |
| 334 | cipher_dealloc(c); |
| 335 | return status; |
| 336 | } |
| 337 | status = cipher_decrypt(c, buffer, &length); |
| 338 | if (status) { |
| 339 | cipher_dealloc(c); |
| 340 | return status; |
| 341 | } |
| 342 | |
| 343 | debug_print(mod_cipher, "plaintext[2]: %s", |
| 344 | octet_string_hex_string(buffer, length)); |
| 345 | |
| 346 | /* compare the resulting plaintext with the original one */ |
| 347 | if (length != plaintext_len) |
| 348 | return err_status_algo_fail; |
| 349 | status = err_status_ok; |
| 350 | for (i=0; i < plaintext_len; i++) |
| 351 | if (buffer[i] != buffer2[i]) { |
| 352 | status = err_status_algo_fail; |
| 353 | debug_print(mod_cipher, "random test case %d failed", case_num); |
| 354 | debug_print(mod_cipher, "(failure at byte %d)", i); |
| 355 | } |
| 356 | if (status) { |
| 357 | cipher_dealloc(c); |
| 358 | return err_status_algo_fail; |
| 359 | } |
| 360 | |
| 361 | } |
| 362 |
|
| 363 | cipher_dealloc(c);
|
| 364 | |
| 365 | return err_status_ok; |
| 366 | } |
| 367 | |
| 368 | |
| 369 | /* |
| 370 | * cipher_bits_per_second(c, l, t) computes (an estimate of) the |
| 371 | * number of bits that a cipher implementation can encrypt in a second |
| 372 | * |
| 373 | * c is a cipher (which MUST be allocated and initialized already), l |
| 374 | * is the length in octets of the test data to be encrypted, and t is |
| 375 | * the number of trials |
| 376 | * |
| 377 | * if an error is encountered, the value 0 is returned |
| 378 | */ |
| 379 | |
| 380 | uint64_t |
| 381 | cipher_bits_per_second(cipher_t *c, int octets_in_buffer, int num_trials) { |
| 382 | int i; |
| 383 | v128_t nonce; |
| 384 | clock_t timer; |
| 385 | unsigned char *enc_buf; |
| 386 | unsigned int len = octets_in_buffer; |
| 387 | |
| 388 | enc_buf = (unsigned char*) crypto_alloc(octets_in_buffer); |
| 389 | if (enc_buf == NULL) |
| 390 | return 0; /* indicate bad parameters by returning null */ |
| 391 | |
| 392 | /* time repeated trials */ |
| 393 | v128_set_to_zero(&nonce); |
| 394 | timer = clock(); |
| 395 | for(i=0; i < num_trials; i++, nonce.v32[3] = i) { |
| 396 | cipher_set_iv(c, &nonce); |
| 397 | cipher_encrypt(c, enc_buf, &len); |
| 398 | } |
| 399 | timer = clock() - timer; |
| 400 | |
| 401 | crypto_free(enc_buf); |
| 402 | |
| 403 | if (timer == 0) { |
| 404 | /* Too fast! */ |
| 405 | return 0; |
| 406 | } |
| 407 | |
| 408 | return (uint64_t)CLOCKS_PER_SEC * num_trials * 8 * octets_in_buffer / timer; |
| 409 | } |