1 /* crypto/bn/exptest.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
65 #include <openssl/bio.h>
66 #include <openssl/bn.h>
67 #include <openssl/rand.h>
68 #include <openssl/err.h>
70 #define NUM_BITS (BN_BITS*2)
72 static const char rnd_seed[] =
73 "string to make the random number generator think it has entropy";
76 * Test that r == 0 in test_exp_mod_zero(). Returns one on success,
77 * returns zero and prints debug output otherwise.
79 static int a_is_zero_mod_one(const char *method, const BIGNUM *r,
82 fprintf(stderr, "%s failed:\n", method);
83 fprintf(stderr, "a ** 0 mod 1 = r (should be 0)\n");
84 fprintf(stderr, "a = ");
85 BN_print_fp(stderr, a);
86 fprintf(stderr, "\nr = ");
87 BN_print_fp(stderr, r);
88 fprintf(stderr, "\n");
95 * test_exp_mod_zero tests that x**0 mod 1 == 0. It returns zero on success.
97 static int test_exp_mod_zero()
101 BN_ULONG one_word = 1;
102 BN_CTX *ctx = BN_CTX_new();
103 int ret = 1, failed = 0;
116 if (!BN_rand(&a, 1024, 0, 0))
119 if (!BN_mod_exp(&r, &a, &p, &m, ctx))
122 if (!a_is_zero_mod_one("BN_mod_exp", &r, &a))
125 if (!BN_mod_exp_recp(&r, &a, &p, &m, ctx))
128 if (!a_is_zero_mod_one("BN_mod_exp_recp", &r, &a))
131 if (!BN_mod_exp_simple(&r, &a, &p, &m, ctx))
134 if (!a_is_zero_mod_one("BN_mod_exp_simple", &r, &a))
137 if (!BN_mod_exp_mont(&r, &a, &p, &m, ctx, NULL))
140 if (!a_is_zero_mod_one("BN_mod_exp_mont", &r, &a))
143 if (!BN_mod_exp_mont_consttime(&r, &a, &p, &m, ctx, NULL)) {
147 if (!a_is_zero_mod_one("BN_mod_exp_mont_consttime", &r, &a))
151 * A different codepath exists for single word multiplication
152 * in non-constant-time only.
154 if (!BN_mod_exp_mont_word(&r, one_word, &p, &m, ctx, NULL))
157 if (!BN_is_zero(&r)) {
158 fprintf(stderr, "BN_mod_exp_mont_word failed:\n");
159 fprintf(stderr, "1 ** 0 mod 1 = r (should be 0)\n");
160 fprintf(stderr, "r = ");
161 BN_print_fp(stderr, &r);
162 fprintf(stderr, "\n");
178 int main(int argc, char *argv[])
184 BIGNUM *r_mont, *r_mont_const, *r_recp, *r_simple, *a, *b, *m;
186 RAND_seed(rnd_seed, sizeof rnd_seed); /* or BN_rand may fail, and we
187 * don't even check its return
188 * value (which we should) */
190 ERR_load_BN_strings();
196 r_mont_const = BN_new();
202 if ((r_mont == NULL) || (r_recp == NULL) || (a == NULL) || (b == NULL))
205 out = BIO_new(BIO_s_file());
209 BIO_set_fp(out, stdout, BIO_NOCLOSE);
211 for (i = 0; i < 200; i++) {
213 c = (c % BN_BITS) - BN_BITS2;
214 BN_rand(a, NUM_BITS + c, 0, 0);
217 c = (c % BN_BITS) - BN_BITS2;
218 BN_rand(b, NUM_BITS + c, 0, 0);
221 c = (c % BN_BITS) - BN_BITS2;
222 BN_rand(m, NUM_BITS + c, 0, 1);
224 BN_mod(a, a, m, ctx);
225 BN_mod(b, b, m, ctx);
227 ret = BN_mod_exp_mont(r_mont, a, b, m, ctx, NULL);
229 printf("BN_mod_exp_mont() problems\n");
230 ERR_print_errors(out);
234 ret = BN_mod_exp_recp(r_recp, a, b, m, ctx);
236 printf("BN_mod_exp_recp() problems\n");
237 ERR_print_errors(out);
241 ret = BN_mod_exp_simple(r_simple, a, b, m, ctx);
243 printf("BN_mod_exp_simple() problems\n");
244 ERR_print_errors(out);
248 ret = BN_mod_exp_mont_consttime(r_mont_const, a, b, m, ctx, NULL);
250 printf("BN_mod_exp_mont_consttime() problems\n");
251 ERR_print_errors(out);
255 if (BN_cmp(r_simple, r_mont) == 0
256 && BN_cmp(r_simple, r_recp) == 0
257 && BN_cmp(r_simple, r_mont_const) == 0) {
261 if (BN_cmp(r_simple, r_mont) != 0)
262 printf("\nsimple and mont results differ\n");
263 if (BN_cmp(r_simple, r_mont_const) != 0)
264 printf("\nsimple and mont const time results differ\n");
265 if (BN_cmp(r_simple, r_recp) != 0)
266 printf("\nsimple and recp results differ\n");
268 printf("a (%3d) = ", BN_num_bits(a));
270 printf("\nb (%3d) = ", BN_num_bits(b));
272 printf("\nm (%3d) = ", BN_num_bits(m));
274 printf("\nsimple =");
275 BN_print(out, r_simple);
277 BN_print(out, r_recp);
279 BN_print(out, r_mont);
280 printf("\nmont_ct =");
281 BN_print(out, r_mont_const);
287 BN_free(r_mont_const);
294 ERR_remove_thread_state(NULL);
295 CRYPTO_mem_leaks(out);
299 if (test_exp_mod_zero() != 0)
306 ERR_load_crypto_strings();
307 ERR_print_errors(out);
308 #ifdef OPENSSL_SYS_NETWARE