Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libcrypto/bn/bn_word.c	Lines:	66	89	74.2 %
Date:	2017-11-07	Branches:	46	68	67.6 %


/* $OpenBSD: bn_word.c,v 1.13 2016/07/05 02:54:35 bcook 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.]
 */

#include <stdio.h>

#include "bn_lcl.h"

BN_ULONG
BN_mod_word(const BIGNUM *a, BN_ULONG w)
{
#ifndef BN_LLONG
	BN_ULONG ret = 0;
#else
	BN_ULLONG ret = 0;
#endif
	int i;

	if (w == 0)
		return (BN_ULONG) - 1;

#ifndef BN_ULLONG
	/* If |w| is too long and we don't have |BN_ULLONG| then we need to fall back
	* to using |BN_div_word|. */
	if (w > ((BN_ULONG)1 << BN_BITS4)) {
		BIGNUM *tmp = BN_dup(a);
		if (tmp == NULL) {
			return (BN_ULONG)-1;
		}
		ret = BN_div_word(tmp, w);
		BN_free(tmp);
		return ret;
	}
#endif

	bn_check_top(a);
	w &= BN_MASK2;
	for (i = a->top - 1; i >= 0; i--) {
#ifndef BN_LLONG
		ret = ((ret << BN_BITS4) | ((a->d[i] >> BN_BITS4) &
		    BN_MASK2l)) % w;
		ret = ((ret << BN_BITS4) | (a->d[i] & BN_MASK2l)) % w;
#else
		ret = (BN_ULLONG)(((ret << (BN_ULLONG)BN_BITS2) |
		    a->d[i]) % (BN_ULLONG)w);
#endif
	}
	return ((BN_ULONG)ret);
}

BN_ULONG
BN_div_word(BIGNUM *a, BN_ULONG w)
{
	BN_ULONG ret = 0;
	int i, j;

	bn_check_top(a);
	w &= BN_MASK2;

	if (!w)
		/* actually this an error (division by zero) */
		return (BN_ULONG) - 1;
	if (a->top == 0)
		return 0;

	/* normalize input (so bn_div_words doesn't complain) */
	j = BN_BITS2 - BN_num_bits_word(w);
	w <<= j;
	if (!BN_lshift(a, a, j))
		return (BN_ULONG) - 1;

	for (i = a->top - 1; i >= 0; i--) {
		BN_ULONG l, d;

		l = a->d[i];
		d = bn_div_words(ret, l, w);
		ret = (l - ((d*w)&BN_MASK2))&BN_MASK2;
		a->d[i] = d;
	}
	if ((a->top > 0) && (a->d[a->top - 1] == 0))
		a->top--;
	ret >>= j;
	bn_check_top(a);
	return (ret);
}

int
BN_add_word(BIGNUM *a, BN_ULONG w)
{
	BN_ULONG l;
	int i;

	bn_check_top(a);
	w &= BN_MASK2;

	/* degenerate case: w is zero */
	if (!w)
		return 1;
	/* degenerate case: a is zero */
	if (BN_is_zero(a))
		return BN_set_word(a, w);
	/* handle 'a' when negative */
	if (a->neg) {
		a->neg = 0;
		i = BN_sub_word(a, w);
		if (!BN_is_zero(a))
			a->neg=!(a->neg);
		return (i);
	}
	for (i = 0; w != 0 && i < a->top; i++) {
		a->d[i] = l = (a->d[i] + w) & BN_MASK2;
		w = (w > l) ? 1 : 0;
	}
	if (w && i == a->top) {
		if (bn_wexpand(a, a->top + 1) == NULL)
			return 0;
		a->top++;
		a->d[i] = w;
	}
	bn_check_top(a);
	return (1);
}

int
BN_sub_word(BIGNUM *a, BN_ULONG w)
{
	int i;

	bn_check_top(a);
	w &= BN_MASK2;

	/* degenerate case: w is zero */
	if (!w)
		return 1;
	/* degenerate case: a is zero */
	if (BN_is_zero(a)) {
		i = BN_set_word(a, w);
		if (i != 0)
			BN_set_negative(a, 1);
		return i;
	}
	/* handle 'a' when negative */
	if (a->neg) {
		a->neg = 0;
		i = BN_add_word(a, w);
		a->neg = 1;
		return (i);
	}

	if ((a->top == 1) && (a->d[0] < w)) {
		a->d[0] = w - a->d[0];
		a->neg = 1;
		return (1);
	}
	i = 0;
	for (;;) {
		if (a->d[i] >= w) {
			a->d[i] -= w;
			break;
		} else {
			a->d[i] = (a->d[i] - w) & BN_MASK2;
			i++;
			w = 1;
		}
	}
	if ((a->d[i] == 0) && (i == (a->top - 1)))
		a->top--;
	bn_check_top(a);
	return (1);
}

int
BN_mul_word(BIGNUM *a, BN_ULONG w)
{
	BN_ULONG ll;

	bn_check_top(a);
	w &= BN_MASK2;
	if (a->top) {
		if (w == 0)
			BN_zero(a);
		else {
			ll = bn_mul_words(a->d, a->d, a->top, w);
			if (ll) {
				if (bn_wexpand(a, a->top + 1) == NULL)
					return (0);
				a->d[a->top++] = ll;
			}
		}
	}
	bn_check_top(a);
	return (1);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: bn_word.c,v 1.13 2016/07/05 02:54:35 bcook 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			#include <stdio.h>
60
61			#include "bn_lcl.h"
62
63			BN_ULONG
64			BN_mod_word(const BIGNUM *a, BN_ULONG w)
65			{
66			#ifndef BN_LLONG
67			BN_ULONG ret = 0;
68			#else
69			BN_ULLONG ret = 0;
70			#endif
71			int i;
72
73	✗✓	226973364	if (w == 0)
74			return (BN_ULONG) - 1;
75
76			#ifndef BN_ULLONG
77			/* If \|w\| is too long and we don't have \|BN_ULLONG\| then we need to fall back
78			* to using \|BN_div_word\|. */
79	✓✓	113486682	if (w > ((BN_ULONG)1 << BN_BITS4)) {
80		578	BIGNUM *tmp = BN_dup(a);
81	✗✓	578	if (tmp == NULL) {
82			return (BN_ULONG)-1;
83			}
84		578	ret = BN_div_word(tmp, w);
85		578	BN_free(tmp);
86		578	return ret;
87			}
88			#endif
89
90			bn_check_top(a);
91			w &= BN_MASK2;
92	✓✓	4991673082	for (i = a->top - 1; i >= 0; i--) {
93			#ifndef BN_LLONG
94		2382350437	ret = ((ret << BN_BITS4) \| ((a->d[i] >> BN_BITS4) &
95		2382350437	BN_MASK2l)) % w;
96		2382350437	ret = ((ret << BN_BITS4) \| (a->d[i] & BN_MASK2l)) % w;
97			#else
98			ret = (BN_ULLONG)(((ret << (BN_ULLONG)BN_BITS2) \|
99			a->d[i]) % (BN_ULLONG)w);
100			#endif
101			}
102		113486104	return ((BN_ULONG)ret);
103		113486682	}
104
105			BN_ULONG
106			BN_div_word(BIGNUM *a, BN_ULONG w)
107			{
108			BN_ULONG ret = 0;
109			int i, j;
110
111			bn_check_top(a);
112			w &= BN_MASK2;
113
114	✗✓	127656	if (!w)
115			/* actually this an error (division by zero) */
116			return (BN_ULONG) - 1;
117	✓✓	63828	if (a->top == 0)
118		634	return 0;
119
120			/* normalize input (so bn_div_words doesn't complain) */
121		63194	j = BN_BITS2 - BN_num_bits_word(w);
122		63194	w <<= j;
123	✗✓	63194	if (!BN_lshift(a, a, j))
124			return (BN_ULONG) - 1;
125
126	✓✓	5794258	for (i = a->top - 1; i >= 0; i--) {
127			BN_ULONG l, d;
128
129		2833935	l = a->d[i];
130		2833935	d = bn_div_words(ret, l, w);
131		2833935	ret = (l - ((d*w)&BN_MASK2))&BN_MASK2;
132		2833935	a->d[i] = d;
133			}
134	✓✗✓✓	126388	if ((a->top > 0) && (a->d[a->top - 1] == 0))
135		60899	a->top--;
136		63194	ret >>= j;
137			bn_check_top(a);
138		63194	return (ret);
139		63828	}
140
141			int
142			BN_add_word(BIGNUM *a, BN_ULONG w)
143			{
144			BN_ULONG l;
145			int i;
146
147			bn_check_top(a);
148			w &= BN_MASK2;
149
150			/* degenerate case: w is zero */
151	✓✓	1552278	if (!w)
152		22039	return 1;
153			/* degenerate case: a is zero */
154	✓✓	754100	if (BN_is_zero(a))
155		33246	return BN_set_word(a, w);
156			/* handle 'a' when negative */
157	✗✓	720854	if (a->neg) {
158			a->neg = 0;
159			i = BN_sub_word(a, w);
160			if (!BN_is_zero(a))
161			a->neg=!(a->neg);
162			return (i);
163			}
164	✓✓✓✗	3605494	for (i = 0; w != 0 && i < a->top; i++) {
165		721262	a->d[i] = l = (a->d[i] + w) & BN_MASK2;
166		721262	w = (w > l) ? 1 : 0;
167			}
168	✗✓✗✗	720854	if (w && i == a->top) {
169			if (bn_wexpand(a, a->top + 1) == NULL)
170			return 0;
171			a->top++;
172			a->d[i] = w;
173			}
174			bn_check_top(a);
175		720854	return (1);
176		776139	}
177
178			int
179			BN_sub_word(BIGNUM *a, BN_ULONG w)
180			{
181			int i;
182
183			bn_check_top(a);
184			w &= BN_MASK2;
185
186			/* degenerate case: w is zero */
187	✗✓	140632	if (!w)
188			return 1;
189			/* degenerate case: a is zero */
190	✓✓	70316	if (BN_is_zero(a)) {
191		5	i = BN_set_word(a, w);
192	✓✗	5	if (i != 0)
193		5	BN_set_negative(a, 1);
194		5	return i;
195			}
196			/* handle 'a' when negative */
197	✗✓	70311	if (a->neg) {
198			a->neg = 0;
199			i = BN_add_word(a, w);
200			a->neg = 1;
201			return (i);
202			}
203
204	✓✓✗✓	76546	if ((a->top == 1) && (a->d[0] < w)) {
205			a->d[0] = w - a->d[0];
206			a->neg = 1;
207			return (1);
208			}
209			i = 0;
210		111344	for (;;) {
211	✓✓	111344	if (a->d[i] >= w) {
212		70311	a->d[i] -= w;
213			break;
214			} else {
215		41033	a->d[i] = (a->d[i] - w) & BN_MASK2;
216		41033	i++;
217			w = 1;
218			}
219			}
220	✓✓✓✓	72171	if ((a->d[i] == 0) && (i == (a->top - 1)))
221		1854	a->top--;
222			bn_check_top(a);
223		70311	return (1);
224		70316	}
225
226			int
227			BN_mul_word(BIGNUM *a, BN_ULONG w)
228			{
229			BN_ULONG ll;
230
231			bn_check_top(a);
232			w &= BN_MASK2;
233	✓✓	233266	if (a->top) {
234	✗✓	76657	if (w == 0)
235			BN_zero(a);
236			else {
237		76657	ll = bn_mul_words(a->d, a->d, a->top, w);
238	✓✓	76657	if (ll) {
239	✓✓✗✓	3416	if (bn_wexpand(a, a->top + 1) == NULL)
240			return (0);
241		1535	a->d[a->top++] = ll;
242		1535	}
243			}
244			}
245			bn_check_top(a);
246		116633	return (1);
247		116633	}