/* crypto/bn/exptest.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../e_os.h"
#include <openssl/bio.h>
#include <openssl/bn.h>
#include <openssl/rand.h>
#include <openssl/err.h>
#define NUM_BITS (BN_BITS*2)
static const char rnd_seed[] =
"string to make the random number generator think it has entropy";
/*
* Test that r == 0 in test_exp_mod_zero(). Returns one on success,
* returns zero and prints debug output otherwise.
*/
static int a_is_zero_mod_one(const char *method, const BIGNUM *r,
const BIGNUM *a) {
if (!BN_is_zero(r)) {
fprintf(stderr, "%s failed:\n", method);
fprintf(stderr, "a ** 0 mod 1 = r (should be 0)\n");
fprintf(stderr, "a = ");
BN_print_fp(stderr, a);
fprintf(stderr, "\nr = ");
BN_print_fp(stderr, r);
fprintf(stderr, "\n");
return 0;
}
return 1;
}
/*
* test_exp_mod_zero tests that x**0 mod 1 == 0. It returns zero on success.
*/
static int test_exp_mod_zero()
{
BIGNUM a, p, m;
BIGNUM r;
BN_ULONG one_word = 1;
BN_CTX *ctx = BN_CTX_new();
int ret = 1, failed = 0;
BN_init(&m);
BN_one(&m);
BN_init(&a);
BN_one(&a);
BN_init(&p);
BN_zero(&p);
BN_init(&r);
if (!BN_rand(&a, 1024, 0, 0))
goto err;
if (!BN_mod_exp(&r, &a, &p, &m, ctx))
goto err;
if (!a_is_zero_mod_one("BN_mod_exp", &r, &a))
failed = 1;
if (!BN_mod_exp_recp(&r, &a, &p, &m, ctx))
goto err;
if (!a_is_zero_mod_one("BN_mod_exp_recp", &r, &a))
failed = 1;
if (!BN_mod_exp_simple(&r, &a, &p, &m, ctx))
goto err;
if (!a_is_zero_mod_one("BN_mod_exp_simple", &r, &a))
failed = 1;
if (!BN_mod_exp_mont(&r, &a, &p, &m, ctx, NULL))
goto err;
if (!a_is_zero_mod_one("BN_mod_exp_mont", &r, &a))
failed = 1;
if (!BN_mod_exp_mont_consttime(&r, &a, &p, &m, ctx, NULL)) {
goto err;
}
if (!a_is_zero_mod_one("BN_mod_exp_mont_consttime", &r, &a))
failed = 1;
/*
* A different codepath exists for single word multiplication
* in non-constant-time only.
*/
if (!BN_mod_exp_mont_word(&r, one_word, &p, &m, ctx, NULL))
goto err;
if (!BN_is_zero(&r)) {
fprintf(stderr, "BN_mod_exp_mont_word failed:\n");
fprintf(stderr, "1 ** 0 mod 1 = r (should be 0)\n");
fprintf(stderr, "r = ");
BN_print_fp(stderr, &r);
fprintf(stderr, "\n");
return 0;
}
ret = failed;
err:
BN_free(&r);
BN_free(&a);
BN_free(&p);
BN_free(&m);
BN_CTX_free(ctx);
return ret;
}
int main(int argc, char *argv[])
{
BN_CTX *ctx;
BIO *out = NULL;
int i, ret;
unsigned char c;
BIGNUM *r_mont, *r_mont_const, *r_recp, *r_simple, *a, *b, *m;
RAND_seed(rnd_seed, sizeof rnd_seed); /* or BN_rand may fail, and we
* don't even check its return
* value (which we should) */
ERR_load_BN_strings();
ctx = BN_CTX_new();
if (ctx == NULL)
EXIT(1);
r_mont = BN_new();
r_mont_const = BN_new();
r_recp = BN_new();
r_simple = BN_new();
a = BN_new();
b = BN_new();
m = BN_new();
if ((r_mont == NULL) || (r_recp == NULL) || (a == NULL) || (b == NULL))
goto err;
out = BIO_new(BIO_s_file());
if (out == NULL)
EXIT(1);
BIO_set_fp(out, stdout, BIO_NOCLOSE);
for (i = 0; i < 200; i++) {
RAND_bytes(&c, 1);
c = (c % BN_BITS) - BN_BITS2;
BN_rand(a, NUM_BITS + c, 0, 0);
RAND_bytes(&c, 1);
c = (c % BN_BITS) - BN_BITS2;
BN_rand(b, NUM_BITS + c, 0, 0);
RAND_bytes(&c, 1);
c = (c % BN_BITS) - BN_BITS2;
BN_rand(m, NUM_BITS + c, 0, 1);
BN_mod(a, a, m, ctx);
BN_mod(b, b, m, ctx);
ret = BN_mod_exp_mont(r_mont, a, b, m, ctx, NULL);
if (ret <= 0) {
printf("BN_mod_exp_mont() problems\n");
ERR_print_errors(out);
EXIT(1);
}
ret = BN_mod_exp_recp(r_recp, a, b, m, ctx);
if (ret <= 0) {
printf("BN_mod_exp_recp() problems\n");
ERR_print_errors(out);
EXIT(1);
}
ret = BN_mod_exp_simple(r_simple, a, b, m, ctx);
if (ret <= 0) {
printf("BN_mod_exp_simple() problems\n");
ERR_print_errors(out);
EXIT(1);
}
ret = BN_mod_exp_mont_consttime(r_mont_const, a, b, m, ctx, NULL);
if (ret <= 0) {
printf("BN_mod_exp_mont_consttime() problems\n");
ERR_print_errors(out);
EXIT(1);
}
if (BN_cmp(r_simple, r_mont) == 0
&& BN_cmp(r_simple, r_recp) == 0
&& BN_cmp(r_simple, r_mont_const) == 0) {
printf(".");
fflush(stdout);
} else {
if (BN_cmp(r_simple, r_mont) != 0)
printf("\nsimple and mont results differ\n");
if (BN_cmp(r_simple, r_mont_const) != 0)
printf("\nsimple and mont const time results differ\n");
if (BN_cmp(r_simple, r_recp) != 0)
printf("\nsimple and recp results differ\n");
printf("a (%3d) = ", BN_num_bits(a));
BN_print(out, a);
printf("\nb (%3d) = ", BN_num_bits(b));
BN_print(out, b);
printf("\nm (%3d) = ", BN_num_bits(m));
BN_print(out, m);
printf("\nsimple =");
BN_print(out, r_simple);
printf("\nrecp =");
BN_print(out, r_recp);
printf("\nmont =");
BN_print(out, r_mont);
printf("\nmont_ct =");
BN_print(out, r_mont_const);
printf("\n");
EXIT(1);
}
}
BN_free(r_mont);
BN_free(r_mont_const);
BN_free(r_recp);
BN_free(r_simple);
BN_free(a);
BN_free(b);
BN_free(m);
BN_CTX_free(ctx);
ERR_remove_thread_state(NULL);
CRYPTO_mem_leaks(out);
BIO_free(out);
printf("\n");
if (test_exp_mod_zero() != 0)
goto err;
printf("done\n");
EXIT(0);
err:
ERR_load_crypto_strings();
ERR_print_errors(out);
#ifdef OPENSSL_SYS_NETWARE
printf("ERROR\n");
#endif
EXIT(1);
return (1);
}