1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/netwerk/srtp/src/crypto/cipher/cipher.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,421 @@
1.4 +/*
1.5 + * cipher.c
1.6 + *
1.7 + * cipher meta-functions
1.8 + *
1.9 + * David A. McGrew
1.10 + * Cisco Systems, Inc.
1.11 + *
1.12 + */
1.13 +
1.14 +/*
1.15 + *
1.16 + * Copyright (c) 2001-2006, Cisco Systems, Inc.
1.17 + * All rights reserved.
1.18 + *
1.19 + * Redistribution and use in source and binary forms, with or without
1.20 + * modification, are permitted provided that the following conditions
1.21 + * are met:
1.22 + *
1.23 + * Redistributions of source code must retain the above copyright
1.24 + * notice, this list of conditions and the following disclaimer.
1.25 + *
1.26 + * Redistributions in binary form must reproduce the above
1.27 + * copyright notice, this list of conditions and the following
1.28 + * disclaimer in the documentation and/or other materials provided
1.29 + * with the distribution.
1.30 + *
1.31 + * Neither the name of the Cisco Systems, Inc. nor the names of its
1.32 + * contributors may be used to endorse or promote products derived
1.33 + * from this software without specific prior written permission.
1.34 + *
1.35 + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.36 + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.37 + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
1.38 + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
1.39 + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
1.40 + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
1.41 + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
1.42 + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.43 + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
1.44 + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.45 + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
1.46 + * OF THE POSSIBILITY OF SUCH DAMAGE.
1.47 + *
1.48 + */
1.49 +
1.50 +#include "cipher.h"
1.51 +#include "rand_source.h" /* used in invertibiltiy tests */
1.52 +#include "alloc.h" /* for crypto_alloc(), crypto_free() */
1.53 +
1.54 +debug_module_t mod_cipher = {
1.55 + 0, /* debugging is off by default */
1.56 + "cipher" /* printable module name */
1.57 +};
1.58 +
1.59 +err_status_t
1.60 +cipher_output(cipher_t *c, uint8_t *buffer, int num_octets_to_output) {
1.61 +
1.62 + /* zeroize the buffer */
1.63 + octet_string_set_to_zero(buffer, num_octets_to_output);
1.64 +
1.65 + /* exor keystream into buffer */
1.66 + return cipher_encrypt(c, buffer, (unsigned int *) &num_octets_to_output);
1.67 +}
1.68 +
1.69 +/* some bookkeeping functions */
1.70 +
1.71 +int
1.72 +cipher_get_key_length(const cipher_t *c) {
1.73 + return c->key_len;
1.74 +}
1.75 +
1.76 +/*
1.77 + * cipher_type_test(ct, test_data) tests a cipher of type ct against
1.78 + * test cases provided in a list test_data of values of key, salt, iv,
1.79 + * plaintext, and ciphertext that is known to be good
1.80 + */
1.81 +
1.82 +#define SELF_TEST_BUF_OCTETS 128
1.83 +#define NUM_RAND_TESTS 128
1.84 +#define MAX_KEY_LEN 64
1.85 +
1.86 +err_status_t
1.87 +cipher_type_test(const cipher_type_t *ct, const cipher_test_case_t *test_data) {
1.88 + const cipher_test_case_t *test_case = test_data;
1.89 + cipher_t *c;
1.90 + err_status_t status;
1.91 + uint8_t buffer[SELF_TEST_BUF_OCTETS];
1.92 + uint8_t buffer2[SELF_TEST_BUF_OCTETS];
1.93 + unsigned int len;
1.94 + int i, j, case_num = 0;
1.95 +
1.96 + debug_print(mod_cipher, "running self-test for cipher %s",
1.97 + ct->description);
1.98 +
1.99 + /*
1.100 + * check to make sure that we have at least one test case, and
1.101 + * return an error if we don't - we need to be paranoid here
1.102 + */
1.103 + if (test_case == NULL)
1.104 + return err_status_cant_check;
1.105 +
1.106 + /*
1.107 + * loop over all test cases, perform known-answer tests of both the
1.108 + * encryption and decryption functions
1.109 + */
1.110 + while (test_case != NULL) {
1.111 +
1.112 + /* allocate cipher */
1.113 + status = cipher_type_alloc(ct, &c, test_case->key_length_octets);
1.114 + if (status)
1.115 + return status;
1.116 +
1.117 + /*
1.118 + * test the encrypt function
1.119 + */
1.120 + debug_print(mod_cipher, "testing encryption", NULL);
1.121 +
1.122 + /* initialize cipher */
1.123 + status = cipher_init(c, test_case->key, direction_encrypt);
1.124 + if (status) {
1.125 + cipher_dealloc(c);
1.126 + return status;
1.127 + }
1.128 +
1.129 + /* copy plaintext into test buffer */
1.130 + if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
1.131 + cipher_dealloc(c);
1.132 + return err_status_bad_param;
1.133 + }
1.134 + for (i=0; i < test_case->plaintext_length_octets; i++)
1.135 + buffer[i] = test_case->plaintext[i];
1.136 +
1.137 + debug_print(mod_cipher, "plaintext: %s",
1.138 + octet_string_hex_string(buffer,
1.139 + test_case->plaintext_length_octets));
1.140 +
1.141 + /* set the initialization vector */
1.142 + status = cipher_set_iv(c, test_case->idx);
1.143 + if (status) {
1.144 + cipher_dealloc(c);
1.145 + return status;
1.146 + }
1.147 +
1.148 + /* encrypt */
1.149 + len = test_case->plaintext_length_octets;
1.150 + status = cipher_encrypt(c, buffer, &len);
1.151 + if (status) {
1.152 + cipher_dealloc(c);
1.153 + return status;
1.154 + }
1.155 +
1.156 + debug_print(mod_cipher, "ciphertext: %s",
1.157 + octet_string_hex_string(buffer,
1.158 + test_case->ciphertext_length_octets));
1.159 +
1.160 + /* compare the resulting ciphertext with that in the test case */
1.161 + if (len != (unsigned int)test_case->ciphertext_length_octets)
1.162 + return err_status_algo_fail;
1.163 + status = err_status_ok;
1.164 + for (i=0; i < test_case->ciphertext_length_octets; i++)
1.165 + if (buffer[i] != test_case->ciphertext[i]) {
1.166 + status = err_status_algo_fail;
1.167 + debug_print(mod_cipher, "test case %d failed", case_num);
1.168 + debug_print(mod_cipher, "(failure at byte %d)", i);
1.169 + break;
1.170 + }
1.171 + if (status) {
1.172 +
1.173 + debug_print(mod_cipher, "c computed: %s",
1.174 + octet_string_hex_string(buffer,
1.175 + 2*test_case->plaintext_length_octets));
1.176 + debug_print(mod_cipher, "c expected: %s",
1.177 + octet_string_hex_string(test_case->ciphertext,
1.178 + 2*test_case->plaintext_length_octets));
1.179 +
1.180 + cipher_dealloc(c);
1.181 + return err_status_algo_fail;
1.182 + }
1.183 +
1.184 + /*
1.185 + * test the decrypt function
1.186 + */
1.187 + debug_print(mod_cipher, "testing decryption", NULL);
1.188 +
1.189 + /* re-initialize cipher for decryption */
1.190 + status = cipher_init(c, test_case->key, direction_decrypt);
1.191 + if (status) {
1.192 + cipher_dealloc(c);
1.193 + return status;
1.194 + }
1.195 +
1.196 + /* copy ciphertext into test buffer */
1.197 + if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
1.198 + cipher_dealloc(c);
1.199 + return err_status_bad_param;
1.200 + }
1.201 + for (i=0; i < test_case->ciphertext_length_octets; i++)
1.202 + buffer[i] = test_case->ciphertext[i];
1.203 +
1.204 + debug_print(mod_cipher, "ciphertext: %s",
1.205 + octet_string_hex_string(buffer,
1.206 + test_case->plaintext_length_octets));
1.207 +
1.208 + /* set the initialization vector */
1.209 + status = cipher_set_iv(c, test_case->idx);
1.210 + if (status) {
1.211 + cipher_dealloc(c);
1.212 + return status;
1.213 + }
1.214 +
1.215 + /* decrypt */
1.216 + len = test_case->ciphertext_length_octets;
1.217 + status = cipher_decrypt(c, buffer, &len);
1.218 + if (status) {
1.219 + cipher_dealloc(c);
1.220 + return status;
1.221 + }
1.222 +
1.223 + debug_print(mod_cipher, "plaintext: %s",
1.224 + octet_string_hex_string(buffer,
1.225 + test_case->plaintext_length_octets));
1.226 +
1.227 + /* compare the resulting plaintext with that in the test case */
1.228 + if (len != (unsigned int)test_case->plaintext_length_octets)
1.229 + return err_status_algo_fail;
1.230 + status = err_status_ok;
1.231 + for (i=0; i < test_case->plaintext_length_octets; i++)
1.232 + if (buffer[i] != test_case->plaintext[i]) {
1.233 + status = err_status_algo_fail;
1.234 + debug_print(mod_cipher, "test case %d failed", case_num);
1.235 + debug_print(mod_cipher, "(failure at byte %d)", i);
1.236 + }
1.237 + if (status) {
1.238 +
1.239 + debug_print(mod_cipher, "p computed: %s",
1.240 + octet_string_hex_string(buffer,
1.241 + 2*test_case->plaintext_length_octets));
1.242 + debug_print(mod_cipher, "p expected: %s",
1.243 + octet_string_hex_string(test_case->plaintext,
1.244 + 2*test_case->plaintext_length_octets));
1.245 +
1.246 + cipher_dealloc(c);
1.247 + return err_status_algo_fail;
1.248 + }
1.249 +
1.250 + /* deallocate the cipher */
1.251 + status = cipher_dealloc(c);
1.252 + if (status)
1.253 + return status;
1.254 +
1.255 + /*
1.256 + * the cipher passed the test case, so move on to the next test
1.257 + * case in the list; if NULL, we'l proceed to the next test
1.258 + */
1.259 + test_case = test_case->next_test_case;
1.260 + ++case_num;
1.261 + }
1.262 +
1.263 + /* now run some random invertibility tests */
1.264 +
1.265 + /* allocate cipher, using paramaters from the first test case */
1.266 + test_case = test_data;
1.267 + status = cipher_type_alloc(ct, &c, test_case->key_length_octets);
1.268 + if (status)
1.269 + return status;
1.270 +
1.271 + rand_source_init();
1.272 +
1.273 + for (j=0; j < NUM_RAND_TESTS; j++) {
1.274 + unsigned length;
1.275 + int plaintext_len;
1.276 + uint8_t key[MAX_KEY_LEN];
1.277 + uint8_t iv[MAX_KEY_LEN];
1.278 +
1.279 + /* choose a length at random (leaving room for IV and padding) */
1.280 + length = rand() % (SELF_TEST_BUF_OCTETS - 64);
1.281 + debug_print(mod_cipher, "random plaintext length %d\n", length);
1.282 + status = rand_source_get_octet_string(buffer, length);
1.283 + if (status) return status;
1.284 +
1.285 + debug_print(mod_cipher, "plaintext: %s",
1.286 + octet_string_hex_string(buffer, length));
1.287 +
1.288 + /* copy plaintext into second buffer */
1.289 + for (i=0; (unsigned int)i < length; i++)
1.290 + buffer2[i] = buffer[i];
1.291 +
1.292 + /* choose a key at random */
1.293 + if (test_case->key_length_octets > MAX_KEY_LEN)
1.294 + return err_status_cant_check;
1.295 + status = rand_source_get_octet_string(key, test_case->key_length_octets);
1.296 + if (status) return status;
1.297 +
1.298 + /* chose a random initialization vector */
1.299 + status = rand_source_get_octet_string(iv, MAX_KEY_LEN);
1.300 + if (status) return status;
1.301 +
1.302 + /* initialize cipher */
1.303 + status = cipher_init(c, key, direction_encrypt);
1.304 + if (status) {
1.305 + cipher_dealloc(c);
1.306 + return status;
1.307 + }
1.308 +
1.309 + /* set initialization vector */
1.310 + status = cipher_set_iv(c, test_case->idx);
1.311 + if (status) {
1.312 + cipher_dealloc(c);
1.313 + return status;
1.314 + }
1.315 +
1.316 + /* encrypt buffer with cipher */
1.317 + plaintext_len = length;
1.318 + status = cipher_encrypt(c, buffer, &length);
1.319 + if (status) {
1.320 + cipher_dealloc(c);
1.321 + return status;
1.322 + }
1.323 + debug_print(mod_cipher, "ciphertext: %s",
1.324 + octet_string_hex_string(buffer, length));
1.325 +
1.326 + /*
1.327 + * re-initialize cipher for decryption, re-set the iv, then
1.328 + * decrypt the ciphertext
1.329 + */
1.330 + status = cipher_init(c, key, direction_decrypt);
1.331 + if (status) {
1.332 + cipher_dealloc(c);
1.333 + return status;
1.334 + }
1.335 + status = cipher_set_iv(c, test_case->idx);
1.336 + if (status) {
1.337 + cipher_dealloc(c);
1.338 + return status;
1.339 + }
1.340 + status = cipher_decrypt(c, buffer, &length);
1.341 + if (status) {
1.342 + cipher_dealloc(c);
1.343 + return status;
1.344 + }
1.345 +
1.346 + debug_print(mod_cipher, "plaintext[2]: %s",
1.347 + octet_string_hex_string(buffer, length));
1.348 +
1.349 + /* compare the resulting plaintext with the original one */
1.350 + if (length != (unsigned)plaintext_len)
1.351 + return err_status_algo_fail;
1.352 + status = err_status_ok;
1.353 + for (i=0; i < plaintext_len; i++)
1.354 + if (buffer[i] != buffer2[i]) {
1.355 + status = err_status_algo_fail;
1.356 + debug_print(mod_cipher, "random test case %d failed", case_num);
1.357 + debug_print(mod_cipher, "(failure at byte %d)", i);
1.358 + }
1.359 + if (status) {
1.360 + cipher_dealloc(c);
1.361 + return err_status_algo_fail;
1.362 + }
1.363 +
1.364 + }
1.365 +
1.366 + status = cipher_dealloc(c);
1.367 + if (status)
1.368 + return status;
1.369 +
1.370 + return err_status_ok;
1.371 +}
1.372 +
1.373 +
1.374 +/*
1.375 + * cipher_type_self_test(ct) performs cipher_type_test on ct's internal
1.376 + * list of test data.
1.377 + */
1.378 +
1.379 +err_status_t
1.380 +cipher_type_self_test(const cipher_type_t *ct) {
1.381 + return cipher_type_test(ct, ct->test_data);
1.382 +}
1.383 +
1.384 +/*
1.385 + * cipher_bits_per_second(c, l, t) computes (an estimate of) the
1.386 + * number of bits that a cipher implementation can encrypt in a second
1.387 + *
1.388 + * c is a cipher (which MUST be allocated and initialized already), l
1.389 + * is the length in octets of the test data to be encrypted, and t is
1.390 + * the number of trials
1.391 + *
1.392 + * if an error is encountered, the value 0 is returned
1.393 + */
1.394 +
1.395 +uint64_t
1.396 +cipher_bits_per_second(cipher_t *c, int octets_in_buffer, int num_trials) {
1.397 + int i;
1.398 + v128_t nonce;
1.399 + clock_t timer;
1.400 + unsigned char *enc_buf;
1.401 + unsigned int len = octets_in_buffer;
1.402 +
1.403 + enc_buf = (unsigned char*) crypto_alloc(octets_in_buffer);
1.404 + if (enc_buf == NULL)
1.405 + return 0; /* indicate bad parameters by returning null */
1.406 +
1.407 + /* time repeated trials */
1.408 + v128_set_to_zero(&nonce);
1.409 + timer = clock();
1.410 + for(i=0; i < num_trials; i++, nonce.v32[3] = i) {
1.411 + cipher_set_iv(c, &nonce);
1.412 + cipher_encrypt(c, enc_buf, &len);
1.413 + }
1.414 + timer = clock() - timer;
1.415 +
1.416 + crypto_free(enc_buf);
1.417 +
1.418 + if (timer == 0) {
1.419 + /* Too fast! */
1.420 + return 0;
1.421 + }
1.422 +
1.423 + return (uint64_t)CLOCKS_PER_SEC * num_trials * 8 * octets_in_buffer / timer;
1.424 +}
