diff options
Diffstat (limited to 'openssl/crypto/bn/bn_mod.c')
-rw-r--r-- | openssl/crypto/bn/bn_mod.c | 353 |
1 files changed, 184 insertions, 169 deletions
diff --git a/openssl/crypto/bn/bn_mod.c b/openssl/crypto/bn/bn_mod.c index 77d6ddb91..ffbce890c 100644 --- a/openssl/crypto/bn/bn_mod.c +++ b/openssl/crypto/bn/bn_mod.c @@ -1,6 +1,8 @@ /* crypto/bn/bn_mod.c */ -/* Includes code written by Lenka Fibikova <fibikova@exp-math.uni-essen.de> - * for the OpenSSL project. */ +/* + * Includes code written by Lenka Fibikova <fibikova@exp-math.uni-essen.de> + * for the OpenSSL project. + */ /* ==================================================================== * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. * @@ -9,7 +11,7 @@ * are met: * * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. + * 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 @@ -60,21 +62,21 @@ * 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: @@ -89,10 +91,10 @@ * 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 + * 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 @@ -104,7 +106,7 @@ * 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 @@ -114,188 +116,201 @@ #include "cryptlib.h" #include "bn_lcl.h" - -#if 0 /* now just a #define */ +#if 0 /* now just a #define */ int BN_mod(BIGNUM *rem, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx) - { - return(BN_div(NULL,rem,m,d,ctx)); - /* note that rem->neg == m->neg (unless the remainder is zero) */ - } +{ + return (BN_div(NULL, rem, m, d, ctx)); + /* note that rem->neg == m->neg (unless the remainder is zero) */ +} #endif - int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx) - { - /* like BN_mod, but returns non-negative remainder - * (i.e., 0 <= r < |d| always holds) */ - - if (!(BN_mod(r,m,d,ctx))) - return 0; - if (!r->neg) - return 1; - /* now -|d| < r < 0, so we have to set r := r + |d| */ - return (d->neg ? BN_sub : BN_add)(r, r, d); +{ + /* + * like BN_mod, but returns non-negative remainder (i.e., 0 <= r < |d| + * always holds) + */ + + if (!(BN_mod(r, m, d, ctx))) + return 0; + if (!r->neg) + return 1; + /* now -|d| < r < 0, so we have to set r := r + |d| */ + return (d->neg ? BN_sub : BN_add) (r, r, d); } +int BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, + BN_CTX *ctx) +{ + if (!BN_add(r, a, b)) + return 0; + return BN_nnmod(r, r, m, ctx); +} -int BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, BN_CTX *ctx) - { - if (!BN_add(r, a, b)) return 0; - return BN_nnmod(r, r, m, ctx); - } - - -/* BN_mod_add variant that may be used if both a and b are non-negative - * and less than m */ -int BN_mod_add_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m) - { - if (!BN_uadd(r, a, b)) return 0; - if (BN_ucmp(r, m) >= 0) - return BN_usub(r, r, m); - return 1; - } - - -int BN_mod_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, BN_CTX *ctx) - { - if (!BN_sub(r, a, b)) return 0; - return BN_nnmod(r, r, m, ctx); - } - +/* + * BN_mod_add variant that may be used if both a and b are non-negative and + * less than m + */ +int BN_mod_add_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, + const BIGNUM *m) +{ + if (!BN_uadd(r, a, b)) + return 0; + if (BN_ucmp(r, m) >= 0) + return BN_usub(r, r, m); + return 1; +} -/* BN_mod_sub variant that may be used if both a and b are non-negative - * and less than m */ -int BN_mod_sub_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m) - { - if (!BN_sub(r, a, b)) return 0; - if (r->neg) - return BN_add(r, r, m); - return 1; - } +int BN_mod_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, + BN_CTX *ctx) +{ + if (!BN_sub(r, a, b)) + return 0; + return BN_nnmod(r, r, m, ctx); +} +/* + * BN_mod_sub variant that may be used if both a and b are non-negative and + * less than m + */ +int BN_mod_sub_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, + const BIGNUM *m) +{ + if (!BN_sub(r, a, b)) + return 0; + if (r->neg) + return BN_add(r, r, m); + return 1; +} /* slow but works */ int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, - BN_CTX *ctx) - { - BIGNUM *t; - int ret=0; - - bn_check_top(a); - bn_check_top(b); - bn_check_top(m); - - BN_CTX_start(ctx); - if ((t = BN_CTX_get(ctx)) == NULL) goto err; - if (a == b) - { if (!BN_sqr(t,a,ctx)) goto err; } - else - { if (!BN_mul(t,a,b,ctx)) goto err; } - if (!BN_nnmod(r,t,m,ctx)) goto err; - bn_check_top(r); - ret=1; -err: - BN_CTX_end(ctx); - return(ret); - } - + BN_CTX *ctx) +{ + BIGNUM *t; + int ret = 0; + + bn_check_top(a); + bn_check_top(b); + bn_check_top(m); + + BN_CTX_start(ctx); + if ((t = BN_CTX_get(ctx)) == NULL) + goto err; + if (a == b) { + if (!BN_sqr(t, a, ctx)) + goto err; + } else { + if (!BN_mul(t, a, b, ctx)) + goto err; + } + if (!BN_nnmod(r, t, m, ctx)) + goto err; + bn_check_top(r); + ret = 1; + err: + BN_CTX_end(ctx); + return (ret); +} int BN_mod_sqr(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx) - { - if (!BN_sqr(r, a, ctx)) return 0; - /* r->neg == 0, thus we don't need BN_nnmod */ - return BN_mod(r, r, m, ctx); - } - +{ + if (!BN_sqr(r, a, ctx)) + return 0; + /* r->neg == 0, thus we don't need BN_nnmod */ + return BN_mod(r, r, m, ctx); +} int BN_mod_lshift1(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx) - { - if (!BN_lshift1(r, a)) return 0; - bn_check_top(r); - return BN_nnmod(r, r, m, ctx); - } - +{ + if (!BN_lshift1(r, a)) + return 0; + bn_check_top(r); + return BN_nnmod(r, r, m, ctx); +} -/* BN_mod_lshift1 variant that may be used if a is non-negative - * and less than m */ +/* + * BN_mod_lshift1 variant that may be used if a is non-negative and less than + * m + */ int BN_mod_lshift1_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *m) - { - if (!BN_lshift1(r, a)) return 0; - bn_check_top(r); - if (BN_cmp(r, m) >= 0) - return BN_sub(r, r, m); - return 1; - } - +{ + if (!BN_lshift1(r, a)) + return 0; + bn_check_top(r); + if (BN_cmp(r, m) >= 0) + return BN_sub(r, r, m); + return 1; +} -int BN_mod_lshift(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m, BN_CTX *ctx) - { - BIGNUM *abs_m = NULL; - int ret; +int BN_mod_lshift(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m, + BN_CTX *ctx) +{ + BIGNUM *abs_m = NULL; + int ret; - if (!BN_nnmod(r, a, m, ctx)) return 0; + if (!BN_nnmod(r, a, m, ctx)) + return 0; - if (m->neg) - { - abs_m = BN_dup(m); - if (abs_m == NULL) return 0; - abs_m->neg = 0; - } - - ret = BN_mod_lshift_quick(r, r, n, (abs_m ? abs_m : m)); - bn_check_top(r); + if (m->neg) { + abs_m = BN_dup(m); + if (abs_m == NULL) + return 0; + abs_m->neg = 0; + } - if (abs_m) - BN_free(abs_m); - return ret; - } + ret = BN_mod_lshift_quick(r, r, n, (abs_m ? abs_m : m)); + bn_check_top(r); + if (abs_m) + BN_free(abs_m); + return ret; +} -/* BN_mod_lshift variant that may be used if a is non-negative - * and less than m */ +/* + * BN_mod_lshift variant that may be used if a is non-negative and less than + * m + */ int BN_mod_lshift_quick(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m) - { - if (r != a) - { - if (BN_copy(r, a) == NULL) return 0; - } - - while (n > 0) - { - int max_shift; - - /* 0 < r < m */ - max_shift = BN_num_bits(m) - BN_num_bits(r); - /* max_shift >= 0 */ - - if (max_shift < 0) - { - BNerr(BN_F_BN_MOD_LSHIFT_QUICK, BN_R_INPUT_NOT_REDUCED); - return 0; - } - - if (max_shift > n) - max_shift = n; - - if (max_shift) - { - if (!BN_lshift(r, r, max_shift)) return 0; - n -= max_shift; - } - else - { - if (!BN_lshift1(r, r)) return 0; - --n; - } - - /* BN_num_bits(r) <= BN_num_bits(m) */ - - if (BN_cmp(r, m) >= 0) - { - if (!BN_sub(r, r, m)) return 0; - } - } - bn_check_top(r); - - return 1; - } +{ + if (r != a) { + if (BN_copy(r, a) == NULL) + return 0; + } + + while (n > 0) { + int max_shift; + + /* 0 < r < m */ + max_shift = BN_num_bits(m) - BN_num_bits(r); + /* max_shift >= 0 */ + + if (max_shift < 0) { + BNerr(BN_F_BN_MOD_LSHIFT_QUICK, BN_R_INPUT_NOT_REDUCED); + return 0; + } + + if (max_shift > n) + max_shift = n; + + if (max_shift) { + if (!BN_lshift(r, r, max_shift)) + return 0; + n -= max_shift; + } else { + if (!BN_lshift1(r, r)) + return 0; + --n; + } + + /* BN_num_bits(r) <= BN_num_bits(m) */ + + if (BN_cmp(r, m) >= 0) { + if (!BN_sub(r, r, m)) + return 0; + } + } + bn_check_top(r); + + return 1; +} |