Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libcrypto/bn/bn_rand.c	Lines:	55	75	73.3 %
Date:	2017-11-07	Branches:	42	56	75.0 %


/* $OpenBSD: bn_rand.c,v 1.20 2017/05/02 03:59:44 deraadt Exp $ */
/* 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.]
 */
/* ====================================================================
 * Copyright (c) 1998-2001 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
 *    openssl-core@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 <stdlib.h>
#include <string.h>
#include <time.h>

#include <openssl/err.h>

#include "bn_lcl.h"

static int
bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
{
	unsigned char *buf = NULL;
	int ret = 0, bit, bytes, mask;

	if (rnd == NULL) {
		BNerror(ERR_R_PASSED_NULL_PARAMETER);
		return (0);
	}

	if (bits == 0) {
		BN_zero(rnd);
		return (1);
	}

	bytes = (bits + 7) / 8;
	bit = (bits - 1) % 8;
	mask = 0xff << (bit + 1);

	buf = malloc(bytes);
	if (buf == NULL) {
		BNerror(ERR_R_MALLOC_FAILURE);
		goto err;
	}

	/* make a random number and set the top and bottom bits */
	arc4random_buf(buf, bytes);

#if 1
	if (pseudorand == 2) {
		/* generate patterns that are more likely to trigger BN
		   library bugs */
		int i;
		unsigned char c;

		for (i = 0; i < bytes; i++) {
			arc4random_buf(&c, 1);
			if (c >= 128 && i > 0)
				buf[i] = buf[i - 1];
			else if (c < 42)
				buf[i] = 0;
			else if (c < 84)
				buf[i] = 255;
		}
	}
#endif

	if (top != -1) {
		if (top) {
			if (bit == 0) {
				buf[0] = 1;
				buf[1] |= 0x80;
			} else {
				buf[0] |= (3 << (bit - 1));
			}
		} else {
			buf[0] |= (1 << bit);
		}
	}
	buf[0] &= ~mask;
	if (bottom) /* set bottom bit if requested */
		buf[bytes - 1] |= 1;
	if (BN_bin2bn(buf, bytes, rnd) == NULL)
		goto err;
	ret = 1;

err:
	freezero(buf, bytes);
	bn_check_top(rnd);
	return (ret);
}

int
BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
{
	return bnrand(0, rnd, bits, top, bottom);
}

int
BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom)
{
	return bnrand(1, rnd, bits, top, bottom);
}

#if 1
int
BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom)
{
	return bnrand(2, rnd, bits, top, bottom);
}
#endif


/* random number r:  0 <= r < range */
static int
bn_rand_range(int pseudo, BIGNUM *r, const BIGNUM *range)
{
	int (*bn_rand)(BIGNUM *, int, int, int) = pseudo ? BN_pseudo_rand : BN_rand;
	int n;
	int count = 100;

	if (range->neg || BN_is_zero(range)) {
		BNerror(BN_R_INVALID_RANGE);
		return 0;
	}

	n = BN_num_bits(range); /* n > 0 */

	/* BN_is_bit_set(range, n - 1) always holds */

	if (n == 1)
		BN_zero(r);
	else if (!BN_is_bit_set(range, n - 2) && !BN_is_bit_set(range, n - 3)) {
		/* range = 100..._2,
		 * so  3*range (= 11..._2)  is exactly one bit longer than  range */
		do {
			if (!bn_rand(r, n + 1, -1, 0))
				return 0;
			/* If  r < 3*range,  use  r := r MOD range
			 * (which is either  r, r - range,  or  r - 2*range).
			 * Otherwise, iterate once more.
			 * Since  3*range = 11..._2, each iteration succeeds with
			 * probability >= .75. */
			if (BN_cmp(r, range) >= 0) {
				if (!BN_sub(r, r, range))
					return 0;
				if (BN_cmp(r, range) >= 0)
					if (!BN_sub(r, r, range))
						return 0;
			}

			if (!--count) {
				BNerror(BN_R_TOO_MANY_ITERATIONS);
				return 0;
			}

		} while (BN_cmp(r, range) >= 0);
	} else {
		do {
			/* range = 11..._2  or  range = 101..._2 */
			if (!bn_rand(r, n, -1, 0))
				return 0;

			if (!--count) {
				BNerror(BN_R_TOO_MANY_ITERATIONS);
				return 0;
			}
		} while (BN_cmp(r, range) >= 0);
	}

	bn_check_top(r);
	return 1;
}

int
BN_rand_range(BIGNUM *r, const BIGNUM *range)
{
	return bn_rand_range(0, r, range);
}

int
BN_pseudo_rand_range(BIGNUM *r, const BIGNUM *range)
{
	return bn_rand_range(1, r, range);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: bn_rand.c,v 1.20 2017/05/02 03:59:44 deraadt Exp $ */
2			/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3			* All rights reserved.
4			*
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.
8			*
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).
15			*
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.
22			*
23			* Redistribution and use in source and binary forms, with or without
24			* modification, are permitted provided that the following conditions
25			* are met:
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)"
40			*
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
51			* SUCH DAMAGE.
52			*
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.]
57			*/
58			/* ====================================================================
59			* Copyright (c) 1998-2001 The OpenSSL Project. All rights reserved.
60			*
61			* Redistribution and use in source and binary forms, with or without
62			* modification, are permitted provided that the following conditions
63			* are met:
64			*
65			* 1. Redistributions of source code must retain the above copyright
66			* notice, this list of conditions and the following disclaimer.
67			*
68			* 2. Redistributions in binary form must reproduce the above copyright
69			* notice, this list of conditions and the following disclaimer in
70			* the documentation and/or other materials provided with the
71			* distribution.
72			*
73			* 3. All advertising materials mentioning features or use of this
74			* software must display the following acknowledgment:
75			* "This product includes software developed by the OpenSSL Project
76			* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77			*
78			* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79			* endorse or promote products derived from this software without
80			* prior written permission. For written permission, please contact
81			* openssl-core@openssl.org.
82			*
83			* 5. Products derived from this software may not be called "OpenSSL"
84			* nor may "OpenSSL" appear in their names without prior written
85			* permission of the OpenSSL Project.
86			*
87			* 6. Redistributions of any form whatsoever must retain the following
88			* acknowledgment:
89			* "This product includes software developed by the OpenSSL Project
90			* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91			*
92			* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93			* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95			* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96			* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97			* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98			* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99			* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101			* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102			* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103			* OF THE POSSIBILITY OF SUCH DAMAGE.
104			* ====================================================================
105			*
106			* This product includes cryptographic software written by Eric Young
107			* (eay@cryptsoft.com). This product includes software written by Tim
108			* Hudson (tjh@cryptsoft.com).
109			*
110			*/
111
112			#include <stdio.h>
113			#include <stdlib.h>
114			#include <string.h>
115			#include <time.h>
116
117			#include <openssl/err.h>
118
119			#include "bn_lcl.h"
120
121			static int
122			bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
123			{
124			unsigned char *buf = NULL;
125			int ret = 0, bit, bytes, mask;
126
127	✗✓	183372	if (rnd == NULL) {
128			BNerror(ERR_R_PASSED_NULL_PARAMETER);
129			return (0);
130			}
131
132	✗✓	91686	if (bits == 0) {
133			BN_zero(rnd);
134			return (1);
135			}
136
137		91686	bytes = (bits + 7) / 8;
138		91686	bit = (bits - 1) % 8;
139		91686	mask = 0xff << (bit + 1);
140
141		91686	buf = malloc(bytes);
142	✗✓	91686	if (buf == NULL) {
143			BNerror(ERR_R_MALLOC_FAILURE);
144			goto err;
145			}
146
147			/* make a random number and set the top and bottom bits */
148		91686	arc4random_buf(buf, bytes);
149
150			#if 1
151	✓✓	91686	if (pseudorand == 2) {
152			/* generate patterns that are more likely to trigger BN
153			library bugs */
154			int i;
155		20324	unsigned char c;
156
157	✓✓	4343667	for (i = 0; i < bytes; i++) {
158		1525308	arc4random_buf(&c, 1);
159	✓✓	1525308	if (c >= 128 && i > 0)
160		752322	buf[i] = buf[i - 1];
161	✓✓	772986	else if (c < 42)
162		250133	buf[i] = 0;
163	✓✓	522853	else if (c < 84)
164		249948	buf[i] = 255;
165			}
166		20324	}
167			#endif
168
169	✓✓	91686	if (top != -1) {
170	✓✓	45214	if (top) {
171	✗✓	3413	if (bit == 0) {
172			buf[0] = 1;
173			buf[1] \|= 0x80;
174			} else {
175		3413	buf[0] \|= (3 << (bit - 1));
176			}
177			} else {
178		41801	buf[0] \|= (1 << bit);
179			}
180		45214	}
181		91686	buf[0] &= ~mask;
182	✓✓	91686	if (bottom) /* set bottom bit if requested */
183		23778	buf[bytes - 1] \|= 1;
184	✓✗	91686	if (BN_bin2bn(buf, bytes, rnd) == NULL)
185			goto err;
186		91686	ret = 1;
187
188			err:
189		91686	freezero(buf, bytes);
190			bn_check_top(rnd);
191		91686	return (ret);
192		91686	}
193
194			int
195			BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
196			{
197		64700	return bnrand(0, rnd, bits, top, bottom);
198			}
199
200			int
201			BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom)
202			{
203		78024	return bnrand(1, rnd, bits, top, bottom);
204			}
205
206			#if 1
207			int
208			BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom)
209			{
210		40648	return bnrand(2, rnd, bits, top, bottom);
211			}
212			#endif
213
214
215			/* random number r: 0 <= r < range */
216			static int
217			bn_rand_range(int pseudo, BIGNUM r, const BIGNUM range)
218			{
219		71854	int (bn_rand)(BIGNUM , int, int, int) = pseudo ? BN_pseudo_rand : BN_rand;
220			int n;
221			int count = 100;
222
223	✓✗✗✓	71854	if (range->neg \|\| BN_is_zero(range)) {
224			BNerror(BN_R_INVALID_RANGE);
225			return 0;
226			}
227
228		35927	n = BN_num_bits(range); /* n > 0 */
229
230			/* BN_is_bit_set(range, n - 1) always holds */
231
232	✗✓	35927	if (n == 1)
233			BN_zero(r);
234	✓✓✓✓	50960	else if (!BN_is_bit_set(range, n - 2) && !BN_is_bit_set(range, n - 3)) {
235			/* range = 100..._2,
236			* so 3range (= 11..._2) is exactly one bit longer than range /
237			do {
238	✗✓	9376	if (!bn_rand(r, n + 1, -1, 0))
239			return 0;
240			/* If r < 3*range, use r := r MOD range
241			* (which is either r, r - range, or r - 2*range).
242			* Otherwise, iterate once more.
243			* Since 3*range = 11..._2, each iteration succeeds with
244			* probability >= .75. */
245	✓✓	9376	if (BN_cmp(r, range) >= 0) {
246	✗✓	6822	if (!BN_sub(r, r, range))
247			return 0;
248	✓✓	6822	if (BN_cmp(r, range) >= 0)
249	✗✓	4216	if (!BN_sub(r, r, range))
250			return 0;
251			}
252
253	✗✓	9376	if (!--count) {
254			BNerror(BN_R_TOO_MANY_ITERATIONS);
255			return 0;
256			}
257
258	✓✓	9376	} while (BN_cmp(r, range) >= 0);
259			} else {
260			do {
261			/* range = 11..._2 or range = 101..._2 */
262	✗✓	34394	if (!bn_rand(r, n, -1, 0))
263			return 0;
264
265	✗✓	34394	if (!--count) {
266			BNerror(BN_R_TOO_MANY_ITERATIONS);
267			return 0;
268			}
269	✓✓	34394	} while (BN_cmp(r, range) >= 0);
270			}
271
272			bn_check_top(r);
273		35927	return 1;
274		35927	}
275
276			int
277			BN_rand_range(BIGNUM r, const BIGNUM range)
278			{
279		8268	return bn_rand_range(0, r, range);
280			}
281
282			int
283			BN_pseudo_rand_range(BIGNUM r, const BIGNUM range)
284			{
285		63586	return bn_rand_range(1, r, range);
286			}