1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/os/ossrv/ssl/libcrypto/src/crypto/bn/bn_word.c Fri Jun 15 03:10:57 2012 +0200
1.3 @@ -0,0 +1,247 @@
1.4 +/* crypto/bn/bn_word.c */
1.5 +/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
1.6 + * All rights reserved.
1.7 + *
1.8 + * This package is an SSL implementation written
1.9 + * by Eric Young (eay@cryptsoft.com).
1.10 + * The implementation was written so as to conform with Netscapes SSL.
1.11 + *
1.12 + * This library is free for commercial and non-commercial use as long as
1.13 + * the following conditions are aheared to. The following conditions
1.14 + * apply to all code found in this distribution, be it the RC4, RSA,
1.15 + * lhash, DES, etc., code; not just the SSL code. The SSL documentation
1.16 + * included with this distribution is covered by the same copyright terms
1.17 + * except that the holder is Tim Hudson (tjh@cryptsoft.com).
1.18 + *
1.19 + * Copyright remains Eric Young's, and as such any Copyright notices in
1.20 + * the code are not to be removed.
1.21 + * If this package is used in a product, Eric Young should be given attribution
1.22 + * as the author of the parts of the library used.
1.23 + * This can be in the form of a textual message at program startup or
1.24 + * in documentation (online or textual) provided with the package.
1.25 + *
1.26 + * Redistribution and use in source and binary forms, with or without
1.27 + * modification, are permitted provided that the following conditions
1.28 + * are met:
1.29 + * 1. Redistributions of source code must retain the copyright
1.30 + * notice, this list of conditions and the following disclaimer.
1.31 + * 2. Redistributions in binary form must reproduce the above copyright
1.32 + * notice, this list of conditions and the following disclaimer in the
1.33 + * documentation and/or other materials provided with the distribution.
1.34 + * 3. All advertising materials mentioning features or use of this software
1.35 + * must display the following acknowledgement:
1.36 + * "This product includes cryptographic software written by
1.37 + * Eric Young (eay@cryptsoft.com)"
1.38 + * The word 'cryptographic' can be left out if the rouines from the library
1.39 + * being used are not cryptographic related :-).
1.40 + * 4. If you include any Windows specific code (or a derivative thereof) from
1.41 + * the apps directory (application code) you must include an acknowledgement:
1.42 + * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
1.43 + *
1.44 + * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
1.45 + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.46 + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.47 + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
1.48 + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1.49 + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
1.50 + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.51 + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
1.52 + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
1.53 + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
1.54 + * SUCH DAMAGE.
1.55 + *
1.56 + * The licence and distribution terms for any publically available version or
1.57 + * derivative of this code cannot be changed. i.e. this code cannot simply be
1.58 + * copied and put under another distribution licence
1.59 + * [including the GNU Public Licence.]
1.60 + */
1.61 +
1.62 +#include <stdio.h>
1.63 +#include "cryptlib.h"
1.64 +#include "bn_lcl.h"
1.65 +
1.66 +EXPORT_C BN_ULONG BN_mod_word(const BIGNUM *a, BN_ULONG w)
1.67 + {
1.68 +#ifndef BN_LLONG
1.69 + BN_ULONG ret=0;
1.70 +#else
1.71 + BN_ULLONG ret=0;
1.72 +#endif
1.73 + int i;
1.74 +
1.75 + if (w == 0)
1.76 + return (BN_ULONG)-1;
1.77 +
1.78 + bn_check_top(a);
1.79 + w&=BN_MASK2;
1.80 + for (i=a->top-1; i>=0; i--)
1.81 + {
1.82 +#ifndef BN_LLONG
1.83 + ret=((ret<<BN_BITS4)|((a->d[i]>>BN_BITS4)&BN_MASK2l))%w;
1.84 + ret=((ret<<BN_BITS4)|(a->d[i]&BN_MASK2l))%w;
1.85 +#else
1.86 + ret=(BN_ULLONG)(((ret<<(BN_ULLONG)BN_BITS2)|a->d[i])%
1.87 + (BN_ULLONG)w);
1.88 +#endif
1.89 + }
1.90 + return((BN_ULONG)ret);
1.91 + }
1.92 +
1.93 +EXPORT_C BN_ULONG BN_div_word(BIGNUM *a, BN_ULONG w)
1.94 + {
1.95 + BN_ULONG ret = 0;
1.96 + int i, j;
1.97 +
1.98 + bn_check_top(a);
1.99 + w &= BN_MASK2;
1.100 +
1.101 + if (!w)
1.102 + /* actually this an error (division by zero) */
1.103 + return (BN_ULONG)-1;
1.104 + if (a->top == 0)
1.105 + return 0;
1.106 +
1.107 + /* normalize input (so bn_div_words doesn't complain) */
1.108 + j = BN_BITS2 - BN_num_bits_word(w);
1.109 + w <<= j;
1.110 + if (!BN_lshift(a, a, j))
1.111 + return (BN_ULONG)-1;
1.112 +
1.113 + for (i=a->top-1; i>=0; i--)
1.114 + {
1.115 + BN_ULONG l,d;
1.116 +
1.117 + l=a->d[i];
1.118 + d=bn_div_words(ret,l,w);
1.119 + ret=(l-((d*w)&BN_MASK2))&BN_MASK2;
1.120 + a->d[i]=d;
1.121 + }
1.122 + if ((a->top > 0) && (a->d[a->top-1] == 0))
1.123 + a->top--;
1.124 + ret >>= j;
1.125 + bn_check_top(a);
1.126 + return(ret);
1.127 + }
1.128 +
1.129 +EXPORT_C int BN_add_word(BIGNUM *a, BN_ULONG w)
1.130 + {
1.131 + BN_ULONG l;
1.132 + int i;
1.133 +
1.134 + bn_check_top(a);
1.135 + w &= BN_MASK2;
1.136 +
1.137 + /* degenerate case: w is zero */
1.138 + if (!w) return 1;
1.139 + /* degenerate case: a is zero */
1.140 + if(BN_is_zero(a)) return BN_set_word(a, w);
1.141 + /* handle 'a' when negative */
1.142 + if (a->neg)
1.143 + {
1.144 + a->neg=0;
1.145 + i=BN_sub_word(a,w);
1.146 + if (!BN_is_zero(a))
1.147 + a->neg=!(a->neg);
1.148 + return(i);
1.149 + }
1.150 + /* Only expand (and risk failing) if it's possibly necessary */
1.151 + if (((BN_ULONG)(a->d[a->top - 1] + 1) == 0) &&
1.152 + (bn_wexpand(a,a->top+1) == NULL))
1.153 + return(0);
1.154 + i=0;
1.155 + for (;;)
1.156 + {
1.157 + if (i >= a->top)
1.158 + l=w;
1.159 + else
1.160 + l=(a->d[i]+w)&BN_MASK2;
1.161 + a->d[i]=l;
1.162 + if (w > l)
1.163 + w=1;
1.164 + else
1.165 + break;
1.166 + i++;
1.167 + }
1.168 + if (i >= a->top)
1.169 + a->top++;
1.170 + bn_check_top(a);
1.171 + return(1);
1.172 + }
1.173 +
1.174 +EXPORT_C int BN_sub_word(BIGNUM *a, BN_ULONG w)
1.175 + {
1.176 + int i;
1.177 +
1.178 + bn_check_top(a);
1.179 + w &= BN_MASK2;
1.180 +
1.181 + /* degenerate case: w is zero */
1.182 + if (!w) return 1;
1.183 + /* degenerate case: a is zero */
1.184 + if(BN_is_zero(a))
1.185 + {
1.186 + i = BN_set_word(a,w);
1.187 + if (i != 0)
1.188 + BN_set_negative(a, 1);
1.189 + return i;
1.190 + }
1.191 + /* handle 'a' when negative */
1.192 + if (a->neg)
1.193 + {
1.194 + a->neg=0;
1.195 + i=BN_add_word(a,w);
1.196 + a->neg=1;
1.197 + return(i);
1.198 + }
1.199 +
1.200 + if ((a->top == 1) && (a->d[0] < w))
1.201 + {
1.202 + a->d[0]=w-a->d[0];
1.203 + a->neg=1;
1.204 + return(1);
1.205 + }
1.206 + i=0;
1.207 + for (;;)
1.208 + {
1.209 + if (a->d[i] >= w)
1.210 + {
1.211 + a->d[i]-=w;
1.212 + break;
1.213 + }
1.214 + else
1.215 + {
1.216 + a->d[i]=(a->d[i]-w)&BN_MASK2;
1.217 + i++;
1.218 + w=1;
1.219 + }
1.220 + }
1.221 + if ((a->d[i] == 0) && (i == (a->top-1)))
1.222 + a->top--;
1.223 + bn_check_top(a);
1.224 + return(1);
1.225 + }
1.226 +
1.227 +EXPORT_C int BN_mul_word(BIGNUM *a, BN_ULONG w)
1.228 + {
1.229 + BN_ULONG ll;
1.230 +
1.231 + bn_check_top(a);
1.232 + w&=BN_MASK2;
1.233 + if (a->top)
1.234 + {
1.235 + if (w == 0)
1.236 + BN_zero(a);
1.237 + else
1.238 + {
1.239 + ll=bn_mul_words(a->d,a->d,a->top,w);
1.240 + if (ll)
1.241 + {
1.242 + if (bn_wexpand(a,a->top+1) == NULL) return(0);
1.243 + a->d[a->top++]=ll;
1.244 + }
1.245 + }
1.246 + }
1.247 + bn_check_top(a);
1.248 + return(1);
1.249 + }
1.250 +