Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libcrypto/bn/bn_x931p.c	Lines:	0	74	0.0 %
Date:	2017-11-07	Branches:	0	104	0.0 %


/* $OpenBSD: bn_x931p.c,v 1.10 2017/01/25 06:15:44 beck Exp $ */
/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
 * project 2005.
 */
/* ====================================================================
 * Copyright (c) 2005 The OpenSSL Project.  All rights reserved.
 *
 * 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 above 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 acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED 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 OpenSSL PROJECT OR
 * ITS 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.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

#include <stdio.h>
#include <openssl/bn.h>

#include "bn_lcl.h"

/* X9.31 routines for prime derivation */

/* X9.31 prime derivation. This is used to generate the primes pi
 * (p1, p2, q1, q2) from a parameter Xpi by checking successive odd
 * integers.
 */

static int
bn_x931_derive_pi(BIGNUM *pi, const BIGNUM *Xpi, BN_CTX *ctx, BN_GENCB *cb)
{
	int i = 0;

	if (!BN_copy(pi, Xpi))
		return 0;
	if (!BN_is_odd(pi) && !BN_add_word(pi, 1))
		return 0;
	for (;;) {
		i++;
		BN_GENCB_call(cb, 0, i);
		/* NB 27 MR is specificed in X9.31 */
		if (BN_is_prime_fasttest_ex(pi, 27, ctx, 1, cb))
			break;
		if (!BN_add_word(pi, 2))
			return 0;
	}
	BN_GENCB_call(cb, 2, i);
	return 1;
}

/* This is the main X9.31 prime derivation function. From parameters
 * Xp1, Xp2 and Xp derive the prime p. If the parameters p1 or p2 are
 * not NULL they will be returned too: this is needed for testing.
 */

int
BN_X931_derive_prime_ex(BIGNUM *p, BIGNUM *p1, BIGNUM *p2, const BIGNUM *Xp,
    const BIGNUM *Xp1, const BIGNUM *Xp2, const BIGNUM *e, BN_CTX *ctx,
    BN_GENCB *cb)
{
	int ret = 0;

	BIGNUM *t, *p1p2, *pm1;

	/* Only even e supported */
	if (!BN_is_odd(e))
		return 0;

	BN_CTX_start(ctx);
	if (p1 == NULL) {
		if ((p1 = BN_CTX_get(ctx)) == NULL)
			goto err;
	}
	if (p2 == NULL) {
		if ((p2 = BN_CTX_get(ctx)) == NULL)
			goto err;
	}

	if ((t = BN_CTX_get(ctx)) == NULL)
		goto err;
	if ((p1p2 = BN_CTX_get(ctx)) == NULL)
		goto err;
	if ((pm1 = BN_CTX_get(ctx)) == NULL)
		goto err;

	if (!bn_x931_derive_pi(p1, Xp1, ctx, cb))
		goto err;

	if (!bn_x931_derive_pi(p2, Xp2, ctx, cb))
		goto err;

	if (!BN_mul(p1p2, p1, p2, ctx))
		goto err;

	/* First set p to value of Rp */

	if (!BN_mod_inverse_ct(p, p2, p1, ctx))
		goto err;

	if (!BN_mul(p, p, p2, ctx))
		goto err;

	if (!BN_mod_inverse_ct(t, p1, p2, ctx))
		goto err;

	if (!BN_mul(t, t, p1, ctx))
		goto err;

	if (!BN_sub(p, p, t))
		goto err;

	if (p->neg && !BN_add(p, p, p1p2))
		goto err;

	/* p now equals Rp */

	if (!BN_mod_sub(p, p, Xp, p1p2, ctx))
		goto err;

	if (!BN_add(p, p, Xp))
		goto err;

	/* p now equals Yp0 */

	for (;;) {
		int i = 1;
		BN_GENCB_call(cb, 0, i++);
		if (!BN_copy(pm1, p))
			goto err;
		if (!BN_sub_word(pm1, 1))
			goto err;
		if (!BN_gcd_ct(t, pm1, e, ctx))
			goto err;
		if (BN_is_one(t)
		/* X9.31 specifies 8 MR and 1 Lucas test or any prime test
		 * offering similar or better guarantees 50 MR is considerably
		 * better.
		 */
		    && BN_is_prime_fasttest_ex(p, 50, ctx, 1, cb))
			break;
		if (!BN_add(p, p, p1p2))
			goto err;
	}

	BN_GENCB_call(cb, 3, 0);

	ret = 1;

err:

	BN_CTX_end(ctx);

	return ret;
}

/* Generate pair of paramters Xp, Xq for X9.31 prime generation.
 * Note: nbits paramter is sum of number of bits in both.
 */

int
BN_X931_generate_Xpq(BIGNUM *Xp, BIGNUM *Xq, int nbits, BN_CTX *ctx)
{
	BIGNUM *t;
	int i;
	int ret = 0;

	/* Number of bits for each prime is of the form
	 * 512+128s for s = 0, 1, ...
	 */
	if ((nbits < 1024) || (nbits & 0xff))
		return 0;
	nbits >>= 1;
	/* The random value Xp must be between sqrt(2) * 2^(nbits-1) and
	 * 2^nbits - 1. By setting the top two bits we ensure that the lower
	 * bound is exceeded.
	 */
	if (!BN_rand(Xp, nbits, 1, 0))
		return 0;

	BN_CTX_start(ctx);
	if ((t = BN_CTX_get(ctx)) == NULL)
		goto err;

	for (i = 0; i < 1000; i++) {
		if (!BN_rand(Xq, nbits, 1, 0))
			goto err;
		/* Check that |Xp - Xq| > 2^(nbits - 100) */
		BN_sub(t, Xp, Xq);
		if (BN_num_bits(t) > (nbits - 100))
			break;
	}

	if (i < 1000)
		ret = 1;

err:
	BN_CTX_end(ctx);

	return ret;
}

/* Generate primes using X9.31 algorithm. Of the values p, p1, p2, Xp1
 * and Xp2 only 'p' needs to be non-NULL. If any of the others are not NULL
 * the relevant parameter will be stored in it.
 *
 * Due to the fact that |Xp - Xq| > 2^(nbits - 100) must be satisfied Xp and Xq
 * are generated using the previous function and supplied as input.
 */

int
BN_X931_generate_prime_ex(BIGNUM *p, BIGNUM *p1, BIGNUM *p2, BIGNUM *Xp1,
    BIGNUM *Xp2, const BIGNUM *Xp, const BIGNUM *e, BN_CTX *ctx, BN_GENCB *cb)
{
	int ret = 0;

	BN_CTX_start(ctx);
	if (Xp1 == NULL) {
		if ((Xp1 = BN_CTX_get(ctx)) == NULL)
			goto error;
	}
	if (Xp2 == NULL) {
		if ((Xp2 = BN_CTX_get(ctx)) == NULL)
			goto error;
	}

	if (!BN_rand(Xp1, 101, 0, 0))
		goto error;
	if (!BN_rand(Xp2, 101, 0, 0))
		goto error;
	if (!BN_X931_derive_prime_ex(p, p1, p2, Xp, Xp1, Xp2, e, ctx, cb))
		goto error;

	ret = 1;

error:
	BN_CTX_end(ctx);

	return ret;
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: bn_x931p.c,v 1.10 2017/01/25 06:15:44 beck Exp $ */
2			/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3			* project 2005.
4			*/
5			/* ====================================================================
6			* Copyright (c) 2005 The OpenSSL Project. All rights reserved.
7			*
8			* Redistribution and use in source and binary forms, with or without
9			* modification, are permitted provided that the following conditions
10			* are met:
11			*
12			* 1. Redistributions of source code must retain the above copyright
13			* notice, this list of conditions and the following disclaimer.
14			*
15			* 2. Redistributions in binary form must reproduce the above copyright
16			* notice, this list of conditions and the following disclaimer in
17			* the documentation and/or other materials provided with the
18			* distribution.
19			*
20			* 3. All advertising materials mentioning features or use of this
21			* software must display the following acknowledgment:
22			* "This product includes software developed by the OpenSSL Project
23			* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24			*
25			* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26			* endorse or promote products derived from this software without
27			* prior written permission. For written permission, please contact
28			* licensing@OpenSSL.org.
29			*
30			* 5. Products derived from this software may not be called "OpenSSL"
31			* nor may "OpenSSL" appear in their names without prior written
32			* permission of the OpenSSL Project.
33			*
34			* 6. Redistributions of any form whatsoever must retain the following
35			* acknowledgment:
36			* "This product includes software developed by the OpenSSL Project
37			* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38			*
39			* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40			* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42			* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43			* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44			* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45			* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46			* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48			* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49			* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50			* OF THE POSSIBILITY OF SUCH DAMAGE.
51			* ====================================================================
52			*
53			* This product includes cryptographic software written by Eric Young
54			* (eay@cryptsoft.com). This product includes software written by Tim
55			* Hudson (tjh@cryptsoft.com).
56			*
57			*/
58
59			#include <stdio.h>
60			#include <openssl/bn.h>
61
62			#include "bn_lcl.h"
63
64			/* X9.31 routines for prime derivation */
65
66			/* X9.31 prime derivation. This is used to generate the primes pi
67			* (p1, p2, q1, q2) from a parameter Xpi by checking successive odd
68			* integers.
69			*/
70
71			static int
72			bn_x931_derive_pi(BIGNUM pi, const BIGNUM Xpi, BN_CTX ctx, BN_GENCB cb)
73			{
74			int i = 0;
75
76			if (!BN_copy(pi, Xpi))
77			return 0;
78			if (!BN_is_odd(pi) && !BN_add_word(pi, 1))
79			return 0;
80			for (;;) {
81			i++;
82			BN_GENCB_call(cb, 0, i);
83			/* NB 27 MR is specificed in X9.31 */
84			if (BN_is_prime_fasttest_ex(pi, 27, ctx, 1, cb))
85			break;
86			if (!BN_add_word(pi, 2))
87			return 0;
88			}
89			BN_GENCB_call(cb, 2, i);
90			return 1;
91			}
92
93			/* This is the main X9.31 prime derivation function. From parameters
94			* Xp1, Xp2 and Xp derive the prime p. If the parameters p1 or p2 are
95			* not NULL they will be returned too: this is needed for testing.
96			*/
97
98			int
99			BN_X931_derive_prime_ex(BIGNUM p, BIGNUM p1, BIGNUM p2, const BIGNUM Xp,
100			const BIGNUM Xp1, const BIGNUM Xp2, const BIGNUM e, BN_CTX ctx,
101			BN_GENCB *cb)
102			{
103			int ret = 0;
104
105			BIGNUM t, p1p2, *pm1;
106
107			/* Only even e supported */
108			if (!BN_is_odd(e))
109			return 0;
110
111			BN_CTX_start(ctx);
112			if (p1 == NULL) {
113			if ((p1 = BN_CTX_get(ctx)) == NULL)
114			goto err;
115			}
116			if (p2 == NULL) {
117			if ((p2 = BN_CTX_get(ctx)) == NULL)
118			goto err;
119			}
120
121			if ((t = BN_CTX_get(ctx)) == NULL)
122			goto err;
123			if ((p1p2 = BN_CTX_get(ctx)) == NULL)
124			goto err;
125			if ((pm1 = BN_CTX_get(ctx)) == NULL)
126			goto err;
127
128			if (!bn_x931_derive_pi(p1, Xp1, ctx, cb))
129			goto err;
130
131			if (!bn_x931_derive_pi(p2, Xp2, ctx, cb))
132			goto err;
133
134			if (!BN_mul(p1p2, p1, p2, ctx))
135			goto err;
136
137			/* First set p to value of Rp */
138
139			if (!BN_mod_inverse_ct(p, p2, p1, ctx))
140			goto err;
141
142			if (!BN_mul(p, p, p2, ctx))
143			goto err;
144
145			if (!BN_mod_inverse_ct(t, p1, p2, ctx))
146			goto err;
147
148			if (!BN_mul(t, t, p1, ctx))
149			goto err;
150
151			if (!BN_sub(p, p, t))
152			goto err;
153
154			if (p->neg && !BN_add(p, p, p1p2))
155			goto err;
156
157			/* p now equals Rp */
158
159			if (!BN_mod_sub(p, p, Xp, p1p2, ctx))
160			goto err;
161
162			if (!BN_add(p, p, Xp))
163			goto err;
164
165			/* p now equals Yp0 */
166
167			for (;;) {
168			int i = 1;
169			BN_GENCB_call(cb, 0, i++);
170			if (!BN_copy(pm1, p))
171			goto err;
172			if (!BN_sub_word(pm1, 1))
173			goto err;
174			if (!BN_gcd_ct(t, pm1, e, ctx))
175			goto err;
176			if (BN_is_one(t)
177			/* X9.31 specifies 8 MR and 1 Lucas test or any prime test
178			* offering similar or better guarantees 50 MR is considerably
179			* better.
180			*/
181			&& BN_is_prime_fasttest_ex(p, 50, ctx, 1, cb))
182			break;
183			if (!BN_add(p, p, p1p2))
184			goto err;
185			}
186
187			BN_GENCB_call(cb, 3, 0);
188
189			ret = 1;
190
191			err:
192
193			BN_CTX_end(ctx);
194
195			return ret;
196			}
197
198			/* Generate pair of paramters Xp, Xq for X9.31 prime generation.
199			* Note: nbits paramter is sum of number of bits in both.
200			*/
201
202			int
203			BN_X931_generate_Xpq(BIGNUM Xp, BIGNUM Xq, int nbits, BN_CTX *ctx)
204			{
205			BIGNUM *t;
206			int i;
207			int ret = 0;
208
209			/* Number of bits for each prime is of the form
210			* 512+128s for s = 0, 1, ...
211			*/
212			if ((nbits < 1024) \|\| (nbits & 0xff))
213			return 0;
214			nbits >>= 1;
215			/* The random value Xp must be between sqrt(2) * 2^(nbits-1) and
216			* 2^nbits - 1. By setting the top two bits we ensure that the lower
217			* bound is exceeded.
218			*/
219			if (!BN_rand(Xp, nbits, 1, 0))
220			return 0;
221
222			BN_CTX_start(ctx);
223			if ((t = BN_CTX_get(ctx)) == NULL)
224			goto err;
225
226			for (i = 0; i < 1000; i++) {
227			if (!BN_rand(Xq, nbits, 1, 0))
228			goto err;
229			/* Check that \|Xp - Xq\| > 2^(nbits - 100) */
230			BN_sub(t, Xp, Xq);
231			if (BN_num_bits(t) > (nbits - 100))
232			break;
233			}
234
235			if (i < 1000)
236			ret = 1;
237
238			err:
239			BN_CTX_end(ctx);
240
241			return ret;
242			}
243
244			/* Generate primes using X9.31 algorithm. Of the values p, p1, p2, Xp1
245			* and Xp2 only 'p' needs to be non-NULL. If any of the others are not NULL
246			* the relevant parameter will be stored in it.
247			*
248			* Due to the fact that \|Xp - Xq\| > 2^(nbits - 100) must be satisfied Xp and Xq
249			* are generated using the previous function and supplied as input.
250			*/
251
252			int
253			BN_X931_generate_prime_ex(BIGNUM p, BIGNUM p1, BIGNUM p2, BIGNUM Xp1,
254			BIGNUM Xp2, const BIGNUM Xp, const BIGNUM e, BN_CTX ctx, BN_GENCB *cb)
255			{
256			int ret = 0;
257
258			BN_CTX_start(ctx);
259			if (Xp1 == NULL) {
260			if ((Xp1 = BN_CTX_get(ctx)) == NULL)
261			goto error;
262			}
263			if (Xp2 == NULL) {
264			if ((Xp2 = BN_CTX_get(ctx)) == NULL)
265			goto error;
266			}
267
268			if (!BN_rand(Xp1, 101, 0, 0))
269			goto error;
270			if (!BN_rand(Xp2, 101, 0, 0))
271			goto error;
272			if (!BN_X931_derive_prime_ex(p, p1, p2, Xp, Xp1, Xp2, e, ctx, cb))
273			goto error;
274
275			ret = 1;
276
277			error:
278			BN_CTX_end(ctx);
279
280			return ret;
281			}