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-rw-r--r--src/lib/libcrypto/bn/bn_lcl.h100
1 files changed, 99 insertions, 1 deletions
diff --git a/src/lib/libcrypto/bn/bn_lcl.h b/src/lib/libcrypto/bn/bn_lcl.h
index e36ccbc4c2..9c959921b4 100644
--- a/src/lib/libcrypto/bn/bn_lcl.h
+++ b/src/lib/libcrypto/bn/bn_lcl.h
@@ -55,6 +55,59 @@
55 * copied and put under another distribution licence 55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.] 56 * [including the GNU Public Licence.]
57 */ 57 */
58/* ====================================================================
59 * Copyright (c) 1998-2000 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 */
58 111
59#ifndef HEADER_BN_LCL_H 112#ifndef HEADER_BN_LCL_H
60#define HEADER_BN_LCL_H 113#define HEADER_BN_LCL_H
@@ -65,6 +118,51 @@
65extern "C" { 118extern "C" {
66#endif 119#endif
67 120
121
122/*
123 * BN_window_bits_for_exponent_size -- macro for sliding window mod_exp functions
124 *
125 *
126 * For window size 'w' (w >= 2) and a random 'b' bits exponent,
127 * the number of multiplications is a constant plus on average
128 *
129 * 2^(w-1) + (b-w)/(w+1);
130 *
131 * here 2^(w-1) is for precomputing the table (we actually need
132 * entries only for windows that have the lowest bit set), and
133 * (b-w)/(w+1) is an approximation for the expected number of
134 * w-bit windows, not counting the first one.
135 *
136 * Thus we should use
137 *
138 * w >= 6 if b > 671
139 * w = 5 if 671 > b > 239
140 * w = 4 if 239 > b > 79
141 * w = 3 if 79 > b > 23
142 * w <= 2 if 23 > b
143 *
144 * (with draws in between). Very small exponents are often selected
145 * with low Hamming weight, so we use w = 1 for b <= 23.
146 */
147#if 1
148#define BN_window_bits_for_exponent_size(b) \
149 ((b) > 671 ? 6 : \
150 (b) > 239 ? 5 : \
151 (b) > 79 ? 4 : \
152 (b) > 23 ? 3 : 1)
153#else
154/* Old SSLeay/OpenSSL table.
155 * Maximum window size was 5, so this table differs for b==1024;
156 * but it coincides for other interesting values (b==160, b==512).
157 */
158#define BN_window_bits_for_exponent_size(b) \
159 ((b) > 255 ? 5 : \
160 (b) > 127 ? 4 : \
161 (b) > 17 ? 3 : 1)
162#endif
163
164
165
68/* Pentium pro 16,16,16,32,64 */ 166/* Pentium pro 16,16,16,32,64 */
69/* Alpha 16,16,16,16.64 */ 167/* Alpha 16,16,16,16.64 */
70#define BN_MULL_SIZE_NORMAL (16) /* 32 */ 168#define BN_MULL_SIZE_NORMAL (16) /* 32 */
@@ -130,7 +228,7 @@ extern "C" {
130/* This is used for internal error checking and is not normally used */ 228/* This is used for internal error checking and is not normally used */
131#ifdef BN_DEBUG 229#ifdef BN_DEBUG
132# include <assert.h> 230# include <assert.h>
133# define bn_check_top(a) assert ((a)->top >= 0 && (a)->top <= (a)->max); 231# define bn_check_top(a) assert ((a)->top >= 0 && (a)->top <= (a)->dmax);
134#else 232#else
135# define bn_check_top(a) 233# define bn_check_top(a)
136#endif 234#endif