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/* 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 <limits.h>
#include <string.h>
#include <openssl/err.h>
#include <openssl/mem.h>
#include "internal.h"
BIGNUM *BN_new(void) {
BIGNUM *bn = OPENSSL_malloc(sizeof(BIGNUM));
if (bn == NULL) {
OPENSSL_PUT_ERROR(BN, ERR_R_MALLOC_FAILURE);
return NULL;
}
OPENSSL_memset(bn, 0, sizeof(BIGNUM));
bn->flags = BN_FLG_MALLOCED;
return bn;
}
void BN_init(BIGNUM *bn) {
OPENSSL_memset(bn, 0, sizeof(BIGNUM));
}
void BN_free(BIGNUM *bn) {
if (bn == NULL) {
return;
}
if ((bn->flags & BN_FLG_STATIC_DATA) == 0) {
OPENSSL_free(bn->d);
}
if (bn->flags & BN_FLG_MALLOCED) {
OPENSSL_free(bn);
} else {
bn->d = NULL;
}
}
void BN_clear_free(BIGNUM *bn) {
char should_free;
if (bn == NULL) {
return;
}
if (bn->d != NULL) {
OPENSSL_cleanse(bn->d, bn->dmax * sizeof(bn->d[0]));
if ((bn->flags & BN_FLG_STATIC_DATA) == 0) {
OPENSSL_free(bn->d);
}
}
should_free = (bn->flags & BN_FLG_MALLOCED) != 0;
OPENSSL_cleanse(bn, sizeof(BIGNUM));
if (should_free) {
OPENSSL_free(bn);
}
}
BIGNUM *BN_dup(const BIGNUM *src) {
BIGNUM *copy;
if (src == NULL) {
return NULL;
}
copy = BN_new();
if (copy == NULL) {
return NULL;
}
if (!BN_copy(copy, src)) {
BN_free(copy);
return NULL;
}
return copy;
}
BIGNUM *BN_copy(BIGNUM *dest, const BIGNUM *src) {
if (src == dest) {
return dest;
}
if (bn_wexpand(dest, src->top) == NULL) {
return NULL;
}
OPENSSL_memcpy(dest->d, src->d, sizeof(src->d[0]) * src->top);
dest->top = src->top;
dest->neg = src->neg;
return dest;
}
void BN_clear(BIGNUM *bn) {
if (bn->d != NULL) {
OPENSSL_memset(bn->d, 0, bn->dmax * sizeof(bn->d[0]));
}
bn->top = 0;
bn->neg = 0;
}
const BIGNUM *BN_value_one(void) {
static const BN_ULONG kOneLimbs[1] = { 1 };
static const BIGNUM kOne = STATIC_BIGNUM(kOneLimbs);
return &kOne;
}
void BN_with_flags(BIGNUM *out, const BIGNUM *in, int flags) {
OPENSSL_memcpy(out, in, sizeof(BIGNUM));
out->flags &= ~BN_FLG_MALLOCED;
out->flags |= BN_FLG_STATIC_DATA | flags;
}
/* BN_num_bits_word returns the minimum number of bits needed to represent the
* value in |l|. */
unsigned BN_num_bits_word(BN_ULONG l) {
static const unsigned char bits[256] = {
0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5,
5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8};
#if defined(OPENSSL_64_BIT)
if (l & 0xffffffff00000000L) {
if (l & 0xffff000000000000L) {
if (l & 0xff00000000000000L) {
return (bits[(int)(l >> 56)] + 56);
} else {
return (bits[(int)(l >> 48)] + 48);
}
} else {
if (l & 0x0000ff0000000000L) {
return (bits[(int)(l >> 40)] + 40);
} else {
return (bits[(int)(l >> 32)] + 32);
}
}
} else
#endif
{
if (l & 0xffff0000L) {
if (l & 0xff000000L) {
return (bits[(int)(l >> 24L)] + 24);
} else {
return (bits[(int)(l >> 16L)] + 16);
}
} else {
if (l & 0xff00L) {
return (bits[(int)(l >> 8)] + 8);
} else {
return (bits[(int)(l)]);
}
}
}
}
unsigned BN_num_bits(const BIGNUM *bn) {
const int max = bn->top - 1;
if (BN_is_zero(bn)) {
return 0;
}
return max*BN_BITS2 + BN_num_bits_word(bn->d[max]);
}
unsigned BN_num_bytes(const BIGNUM *bn) {
return (BN_num_bits(bn) + 7) / 8;
}
void BN_zero(BIGNUM *bn) {
bn->top = bn->neg = 0;
}
int BN_one(BIGNUM *bn) {
return BN_set_word(bn, 1);
}
int BN_set_word(BIGNUM *bn, BN_ULONG value) {
if (value == 0) {
BN_zero(bn);
return 1;
}
if (bn_wexpand(bn, 1) == NULL) {
return 0;
}
bn->neg = 0;
bn->d[0] = value;
bn->top = 1;
return 1;
}
int BN_set_u64(BIGNUM *bn, uint64_t value) {
#if BN_BITS2 == 64
return BN_set_word(bn, value);
#elif BN_BITS2 == 32
if (value <= BN_MASK2) {
return BN_set_word(bn, (BN_ULONG)value);
}
if (bn_wexpand(bn, 2) == NULL) {
return 0;
}
bn->neg = 0;
bn->d[0] = (BN_ULONG)value;
bn->d[1] = (BN_ULONG)(value >> 32);
bn->top = 2;
return 1;
#else
#error "BN_BITS2 must be 32 or 64."
#endif
}
int bn_set_words(BIGNUM *bn, const BN_ULONG *words, size_t num) {
if (bn_wexpand(bn, num) == NULL) {
return 0;
}
OPENSSL_memmove(bn->d, words, num * sizeof(BN_ULONG));
/* |bn_wexpand| verified that |num| isn't too large. */
bn->top = (int)num;
bn_correct_top(bn);
bn->neg = 0;
return 1;
}
int BN_is_negative(const BIGNUM *bn) {
return bn->neg != 0;
}
void BN_set_negative(BIGNUM *bn, int sign) {
if (sign && !BN_is_zero(bn)) {
bn->neg = 1;
} else {
bn->neg = 0;
}
}
BIGNUM *bn_wexpand(BIGNUM *bn, size_t words) {
BN_ULONG *a;
if (words <= (size_t)bn->dmax) {
return bn;
}
if (words > (INT_MAX / (4 * BN_BITS2))) {
OPENSSL_PUT_ERROR(BN, BN_R_BIGNUM_TOO_LONG);
return NULL;
}
if (bn->flags & BN_FLG_STATIC_DATA) {
OPENSSL_PUT_ERROR(BN, BN_R_EXPAND_ON_STATIC_BIGNUM_DATA);
return NULL;
}
a = OPENSSL_malloc(sizeof(BN_ULONG) * words);
if (a == NULL) {
OPENSSL_PUT_ERROR(BN, ERR_R_MALLOC_FAILURE);
return NULL;
}
OPENSSL_memcpy(a, bn->d, sizeof(BN_ULONG) * bn->top);
OPENSSL_free(bn->d);
bn->d = a;
bn->dmax = (int)words;
return bn;
}
BIGNUM *bn_expand(BIGNUM *bn, size_t bits) {
if (bits + BN_BITS2 - 1 < bits) {
OPENSSL_PUT_ERROR(BN, BN_R_BIGNUM_TOO_LONG);
return NULL;
}
return bn_wexpand(bn, (bits+BN_BITS2-1)/BN_BITS2);
}
void bn_correct_top(BIGNUM *bn) {
BN_ULONG *ftl;
int tmp_top = bn->top;
if (tmp_top > 0) {
for (ftl = &(bn->d[tmp_top - 1]); tmp_top > 0; tmp_top--) {
if (*(ftl--)) {
break;
}
}
bn->top = tmp_top;
}
if (bn->top == 0) {
bn->neg = 0;
}
}
int BN_get_flags(const BIGNUM *bn, int flags) {
return bn->flags & flags;
}
void BN_set_flags(BIGNUM *bn, int flags) {
bn->flags |= flags;
}