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| author | markus <> | 2002-09-05 12:51:50 +0000 |
|---|---|---|
| committer | markus <> | 2002-09-05 12:51:50 +0000 |
| commit | 15b5d84f9da2ce4bfae8580e56e34a859f74ad71 (patch) | |
| tree | bf939e82d7fd73cc8a01cf6959002209972091bc /src/lib/libcrypto/bn/bn_mod.c | |
| parent | 027351f729b9e837200dae6e1520cda6577ab930 (diff) | |
| download | openbsd-15b5d84f9da2ce4bfae8580e56e34a859f74ad71.tar.gz openbsd-15b5d84f9da2ce4bfae8580e56e34a859f74ad71.tar.bz2 openbsd-15b5d84f9da2ce4bfae8580e56e34a859f74ad71.zip | |
import openssl-0.9.7-beta1
Diffstat (limited to 'src/lib/libcrypto/bn/bn_mod.c')
| -rw-r--r-- | src/lib/libcrypto/bn/bn_mod.c | 251 |
1 files changed, 225 insertions, 26 deletions
diff --git a/src/lib/libcrypto/bn/bn_mod.c b/src/lib/libcrypto/bn/bn_mod.c index c351aac14f..5cf82480d7 100644 --- a/src/lib/libcrypto/bn/bn_mod.c +++ b/src/lib/libcrypto/bn/bn_mod.c | |||
| @@ -1,4 +1,59 @@ | |||
| 1 | /* crypto/bn/bn_mod.c */ | 1 | /* crypto/bn/bn_mod.c */ |
| 2 | /* Includes code written by Lenka Fibikova <fibikova@exp-math.uni-essen.de> | ||
| 3 | * for the OpenSSL project. */ | ||
| 4 | /* ==================================================================== | ||
| 5 | * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. | ||
| 6 | * | ||
| 7 | * Redistribution and use in source and binary forms, with or without | ||
| 8 | * modification, are permitted provided that the following conditions | ||
| 9 | * are met: | ||
| 10 | * | ||
| 11 | * 1. Redistributions of source code must retain the above copyright | ||
| 12 | * notice, this list of conditions and the following disclaimer. | ||
| 13 | * | ||
| 14 | * 2. Redistributions in binary form must reproduce the above copyright | ||
| 15 | * notice, this list of conditions and the following disclaimer in | ||
| 16 | * the documentation and/or other materials provided with the | ||
| 17 | * distribution. | ||
| 18 | * | ||
| 19 | * 3. All advertising materials mentioning features or use of this | ||
| 20 | * software must display the following acknowledgment: | ||
| 21 | * "This product includes software developed by the OpenSSL Project | ||
| 22 | * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" | ||
| 23 | * | ||
| 24 | * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to | ||
| 25 | * endorse or promote products derived from this software without | ||
| 26 | * prior written permission. For written permission, please contact | ||
| 27 | * openssl-core@openssl.org. | ||
| 28 | * | ||
| 29 | * 5. Products derived from this software may not be called "OpenSSL" | ||
| 30 | * nor may "OpenSSL" appear in their names without prior written | ||
| 31 | * permission of the OpenSSL Project. | ||
| 32 | * | ||
| 33 | * 6. Redistributions of any form whatsoever must retain the following | ||
| 34 | * acknowledgment: | ||
| 35 | * "This product includes software developed by the OpenSSL Project | ||
| 36 | * for use in the OpenSSL Toolkit (http://www.openssl.org/)" | ||
| 37 | * | ||
| 38 | * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY | ||
| 39 | * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
| 40 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | ||
| 41 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR | ||
| 42 | * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | ||
| 43 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | ||
| 44 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | ||
| 45 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | ||
| 46 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | ||
| 47 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | ||
| 48 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED | ||
| 49 | * OF THE POSSIBILITY OF SUCH DAMAGE. | ||
| 50 | * ==================================================================== | ||
| 51 | * | ||
| 52 | * This product includes cryptographic software written by Eric Young | ||
| 53 | * (eay@cryptsoft.com). This product includes software written by Tim | ||
| 54 | * Hudson (tjh@cryptsoft.com). | ||
| 55 | * | ||
| 56 | */ | ||
| 2 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) | 57 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) |
| 3 | * All rights reserved. | 58 | * All rights reserved. |
| 4 | * | 59 | * |
| @@ -56,42 +111,186 @@ | |||
| 56 | * [including the GNU Public Licence.] | 111 | * [including the GNU Public Licence.] |
| 57 | */ | 112 | */ |
| 58 | 113 | ||
| 59 | #include <stdio.h> | ||
| 60 | #include "cryptlib.h" | 114 | #include "cryptlib.h" |
| 61 | #include "bn_lcl.h" | 115 | #include "bn_lcl.h" |
| 62 | 116 | ||
| 63 | /* rem != m */ | 117 | |
| 64 | int BN_mod(rem, m, d,ctx) | 118 | #if 0 /* now just a #define */ |
| 65 | BIGNUM *rem; | 119 | int BN_mod(BIGNUM *rem, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx) |
| 66 | BIGNUM *m; | 120 | { |
| 67 | BIGNUM *d; | 121 | return(BN_div(NULL,rem,m,d,ctx)); |
| 68 | BN_CTX *ctx; | 122 | /* note that rem->neg == m->neg (unless the remainder is zero) */ |
| 123 | } | ||
| 124 | #endif | ||
| 125 | |||
| 126 | |||
| 127 | int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx) | ||
| 128 | { | ||
| 129 | /* like BN_mod, but returns non-negative remainder | ||
| 130 | * (i.e., 0 <= r < |d| always holds) */ | ||
| 131 | |||
| 132 | if (!(BN_mod(r,m,d,ctx))) | ||
| 133 | return 0; | ||
| 134 | if (!r->neg) | ||
| 135 | return 1; | ||
| 136 | /* now -|d| < r < 0, so we have to set r := r + |d| */ | ||
| 137 | return (d->neg ? BN_sub : BN_add)(r, r, d); | ||
| 138 | } | ||
| 139 | |||
| 140 | |||
| 141 | int BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, BN_CTX *ctx) | ||
| 142 | { | ||
| 143 | if (!BN_add(r, a, b)) return 0; | ||
| 144 | return BN_nnmod(r, r, m, ctx); | ||
| 145 | } | ||
| 146 | |||
| 147 | |||
| 148 | /* BN_mod_add variant that may be used if both a and b are non-negative | ||
| 149 | * and less than m */ | ||
| 150 | int BN_mod_add_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m) | ||
| 151 | { | ||
| 152 | if (!BN_add(r, a, b)) return 0; | ||
| 153 | if (BN_ucmp(r, m) >= 0) | ||
| 154 | return BN_usub(r, r, m); | ||
| 155 | return 1; | ||
| 156 | } | ||
| 157 | |||
| 158 | |||
| 159 | int BN_mod_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, BN_CTX *ctx) | ||
| 160 | { | ||
| 161 | if (!BN_sub(r, a, b)) return 0; | ||
| 162 | return BN_nnmod(r, r, m, ctx); | ||
| 163 | } | ||
| 164 | |||
| 165 | |||
| 166 | /* BN_mod_sub variant that may be used if both a and b are non-negative | ||
| 167 | * and less than m */ | ||
| 168 | int BN_mod_sub_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m) | ||
| 169 | { | ||
| 170 | if (!BN_sub(r, a, b)) return 0; | ||
| 171 | if (r->neg) | ||
| 172 | return BN_add(r, r, m); | ||
| 173 | return 1; | ||
| 174 | } | ||
| 175 | |||
| 176 | |||
| 177 | /* slow but works */ | ||
| 178 | int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, | ||
| 179 | BN_CTX *ctx) | ||
| 69 | { | 180 | { |
| 70 | #if 0 /* The old slow way */ | 181 | BIGNUM *t; |
| 71 | int i,nm,nd; | 182 | int ret=0; |
| 72 | BIGNUM *dv; | 183 | |
| 184 | bn_check_top(a); | ||
| 185 | bn_check_top(b); | ||
| 186 | bn_check_top(m); | ||
| 187 | |||
| 188 | BN_CTX_start(ctx); | ||
| 189 | if ((t = BN_CTX_get(ctx)) == NULL) goto err; | ||
| 190 | if (a == b) | ||
| 191 | { if (!BN_sqr(t,a,ctx)) goto err; } | ||
| 192 | else | ||
| 193 | { if (!BN_mul(t,a,b,ctx)) goto err; } | ||
| 194 | if (!BN_nnmod(r,t,m,ctx)) goto err; | ||
| 195 | ret=1; | ||
| 196 | err: | ||
| 197 | BN_CTX_end(ctx); | ||
| 198 | return(ret); | ||
| 199 | } | ||
| 73 | 200 | ||
| 74 | if (BN_ucmp(m,d) < 0) | ||
| 75 | return((BN_copy(rem,m) == NULL)?0:1); | ||
| 76 | 201 | ||
| 77 | dv=ctx->bn[ctx->tos]; | 202 | int BN_mod_sqr(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx) |
| 203 | { | ||
| 204 | if (!BN_sqr(r, a, ctx)) return 0; | ||
| 205 | /* r->neg == 0, thus we don't need BN_nnmod */ | ||
| 206 | return BN_mod(r, r, m, ctx); | ||
| 207 | } | ||
| 78 | 208 | ||
| 79 | if (!BN_copy(rem,m)) return(0); | ||
| 80 | 209 | ||
| 81 | nm=BN_num_bits(rem); | 210 | int BN_mod_lshift1(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx) |
| 82 | nd=BN_num_bits(d); | 211 | { |
| 83 | if (!BN_lshift(dv,d,nm-nd)) return(0); | 212 | if (!BN_lshift1(r, a)) return 0; |
| 84 | for (i=nm-nd; i>=0; i--) | 213 | return BN_nnmod(r, r, m, ctx); |
| 214 | } | ||
| 215 | |||
| 216 | |||
| 217 | /* BN_mod_lshift1 variant that may be used if a is non-negative | ||
| 218 | * and less than m */ | ||
| 219 | int BN_mod_lshift1_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *m) | ||
| 220 | { | ||
| 221 | if (!BN_lshift1(r, a)) return 0; | ||
| 222 | if (BN_cmp(r, m) >= 0) | ||
| 223 | return BN_sub(r, r, m); | ||
| 224 | return 1; | ||
| 225 | } | ||
| 226 | |||
| 227 | |||
| 228 | int BN_mod_lshift(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m, BN_CTX *ctx) | ||
| 229 | { | ||
| 230 | BIGNUM *abs_m = NULL; | ||
| 231 | int ret; | ||
| 232 | |||
| 233 | if (!BN_nnmod(r, a, m, ctx)) return 0; | ||
| 234 | |||
| 235 | if (m->neg) | ||
| 85 | { | 236 | { |
| 86 | if (BN_cmp(rem,dv) >= 0) | 237 | abs_m = BN_dup(m); |
| 238 | if (abs_m == NULL) return 0; | ||
| 239 | abs_m->neg = 0; | ||
| 240 | } | ||
| 241 | |||
| 242 | ret = BN_mod_lshift_quick(r, r, n, (abs_m ? abs_m : m)); | ||
| 243 | |||
| 244 | if (abs_m) | ||
| 245 | BN_free(abs_m); | ||
| 246 | return ret; | ||
| 247 | } | ||
| 248 | |||
| 249 | |||
| 250 | /* BN_mod_lshift variant that may be used if a is non-negative | ||
| 251 | * and less than m */ | ||
| 252 | int BN_mod_lshift_quick(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m) | ||
| 253 | { | ||
| 254 | if (r != a) | ||
| 255 | { | ||
| 256 | if (BN_copy(r, a) == NULL) return 0; | ||
| 257 | } | ||
| 258 | |||
| 259 | while (n > 0) | ||
| 260 | { | ||
| 261 | int max_shift; | ||
| 262 | |||
| 263 | /* 0 < r < m */ | ||
| 264 | max_shift = BN_num_bits(m) - BN_num_bits(r); | ||
| 265 | /* max_shift >= 0 */ | ||
| 266 | |||
| 267 | if (max_shift < 0) | ||
| 268 | { | ||
| 269 | BNerr(BN_F_BN_MOD_LSHIFT_QUICK, BN_R_INPUT_NOT_REDUCED); | ||
| 270 | return 0; | ||
| 271 | } | ||
| 272 | |||
| 273 | if (max_shift > n) | ||
| 274 | max_shift = n; | ||
| 275 | |||
| 276 | if (max_shift) | ||
| 277 | { | ||
| 278 | if (!BN_lshift(r, r, max_shift)) return 0; | ||
| 279 | n -= max_shift; | ||
| 280 | } | ||
| 281 | else | ||
| 282 | { | ||
| 283 | if (!BN_lshift1(r, r)) return 0; | ||
| 284 | --n; | ||
| 285 | } | ||
| 286 | |||
| 287 | /* BN_num_bits(r) <= BN_num_bits(m) */ | ||
| 288 | |||
| 289 | if (BN_cmp(r, m) >= 0) | ||
| 87 | { | 290 | { |
| 88 | if (!BN_sub(rem,rem,dv)) return(0); | 291 | if (!BN_sub(r, r, m)) return 0; |
| 89 | } | 292 | } |
| 90 | if (!BN_rshift1(dv,dv)) return(0); | ||
| 91 | } | 293 | } |
| 92 | return(1); | 294 | |
| 93 | #else | 295 | return 1; |
| 94 | return(BN_div(NULL,rem,m,d,ctx)); | ||
| 95 | #endif | ||
| 96 | } | 296 | } |
| 97 | |||
