/* 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 <openssl/bn.h>
#include <openssl/mem.h>
#include "internal.h"
int BN_ucmp(const BIGNUM *a, const BIGNUM *b) {
int i;
BN_ULONG t1, t2, *ap, *bp;
i = a->top - b->top;
if (i != 0) {
return i;
}
ap = a->d;
bp = b->d;
for (i = a->top - 1; i >= 0; i--) {
t1 = ap[i];
t2 = bp[i];
if (t1 != t2) {
return (t1 > t2) ? 1 : -1;
}
}
return 0;
}
int BN_cmp(const BIGNUM *a, const BIGNUM *b) {
int i;
int gt, lt;
BN_ULONG t1, t2;
if ((a == NULL) || (b == NULL)) {
if (a != NULL) {
return -1;
} else if (b != NULL) {
return 1;
} else {
return 0;
}
}
if (a->neg != b->neg) {
if (a->neg) {
return -1;
}
return 1;
}
if (a->neg == 0) {
gt = 1;
lt = -1;
} else {
gt = -1;
lt = 1;
}
if (a->top > b->top) {
return gt;
}
if (a->top < b->top) {
return lt;
}
for (i = a->top - 1; i >= 0; i--) {
t1 = a->d[i];
t2 = b->d[i];
if (t1 > t2) {
return gt;
} if (t1 < t2) {
return lt;
}
}
return 0;
}
int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n) {
int i;
BN_ULONG aa, bb;
aa = a[n - 1];
bb = b[n - 1];
if (aa != bb) {
return (aa > bb) ? 1 : -1;
}
for (i = n - 2; i >= 0; i--) {
aa = a[i];
bb = b[i];
if (aa != bb) {
return (aa > bb) ? 1 : -1;
}
}
return 0;
}
int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, int cl, int dl) {
int n, i;
n = cl - 1;
if (dl < 0) {
for (i = dl; i < 0; i++) {
if (b[n - i] != 0) {
return -1; /* a < b */
}
}
}
if (dl > 0) {
for (i = dl; i > 0; i--) {
if (a[n + i] != 0) {
return 1; /* a > b */
}
}
}
return bn_cmp_words(a, b, cl);
}
int BN_abs_is_word(const BIGNUM *bn, BN_ULONG w) {
switch (bn->top) {
case 1:
return bn->d[0] == w;
case 0:
return w == 0;
default:
return 0;
}
}
int BN_cmp_word(const BIGNUM *a, BN_ULONG b) {
BIGNUM b_bn;
BN_init(&b_bn);
b_bn.d = &b;
b_bn.top = b > 0;
b_bn.dmax = 1;
b_bn.flags = BN_FLG_STATIC_DATA;
return BN_cmp(a, &b_bn);
}
int BN_is_zero(const BIGNUM *bn) {
return bn->top == 0;
}
int BN_is_one(const BIGNUM *bn) {
return bn->neg == 0 && BN_abs_is_word(bn, 1);
}
int BN_is_word(const BIGNUM *bn, BN_ULONG w) {
return BN_abs_is_word(bn, w) && (w == 0 || bn->neg == 0);
}
int BN_is_odd(const BIGNUM *bn) {
return bn->top > 0 && (bn->d[0] & 1) == 1;
}
int BN_is_pow2(const BIGNUM *bn) {
if (bn->top == 0 || bn->neg) {
return 0;
}
for (int i = 0; i < bn->top - 1; i++) {
if (bn->d[i] != 0) {
return 0;
}
}
return 0 == (bn->d[bn->top-1] & (bn->d[bn->top-1] - 1));
}
int BN_equal_consttime(const BIGNUM *a, const BIGNUM *b) {
if (a->top != b->top) {
return 0;
}
int limbs_are_equal =
CRYPTO_memcmp(a->d, b->d, (size_t)a->top * sizeof(a->d[0])) == 0;
return constant_time_select_int(constant_time_eq_int(a->neg, b->neg),
limbs_are_equal, 0);
}