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Diffstat (limited to 'thirdparty/openssl/crypto/bn/bn_lib.c')
| -rw-r--r-- | thirdparty/openssl/crypto/bn/bn_lib.c | 916 |
1 files changed, 0 insertions, 916 deletions
diff --git a/thirdparty/openssl/crypto/bn/bn_lib.c b/thirdparty/openssl/crypto/bn/bn_lib.c deleted file mode 100644 index 10b78f5126..0000000000 --- a/thirdparty/openssl/crypto/bn/bn_lib.c +++ /dev/null @@ -1,916 +0,0 @@ -/* crypto/bn/bn_lib.c */ -/* 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.] - */ - -#ifndef BN_DEBUG -# undef NDEBUG /* avoid conflicting definitions */ -# define NDEBUG -#endif - -#include <assert.h> -#include <limits.h> -#include <stdio.h> -#include "cryptlib.h" -#include "bn_lcl.h" - -const char BN_version[] = "Big Number" OPENSSL_VERSION_PTEXT; - -/* This stuff appears to be completely unused, so is deprecated */ -#ifndef OPENSSL_NO_DEPRECATED -/*- - * For a 32 bit machine - * 2 - 4 == 128 - * 3 - 8 == 256 - * 4 - 16 == 512 - * 5 - 32 == 1024 - * 6 - 64 == 2048 - * 7 - 128 == 4096 - * 8 - 256 == 8192 - */ -static int bn_limit_bits = 0; -static int bn_limit_num = 8; /* (1<<bn_limit_bits) */ -static int bn_limit_bits_low = 0; -static int bn_limit_num_low = 8; /* (1<<bn_limit_bits_low) */ -static int bn_limit_bits_high = 0; -static int bn_limit_num_high = 8; /* (1<<bn_limit_bits_high) */ -static int bn_limit_bits_mont = 0; -static int bn_limit_num_mont = 8; /* (1<<bn_limit_bits_mont) */ - -void BN_set_params(int mult, int high, int low, int mont) -{ - if (mult >= 0) { - if (mult > (int)(sizeof(int) * 8) - 1) - mult = sizeof(int) * 8 - 1; - bn_limit_bits = mult; - bn_limit_num = 1 << mult; - } - if (high >= 0) { - if (high > (int)(sizeof(int) * 8) - 1) - high = sizeof(int) * 8 - 1; - bn_limit_bits_high = high; - bn_limit_num_high = 1 << high; - } - if (low >= 0) { - if (low > (int)(sizeof(int) * 8) - 1) - low = sizeof(int) * 8 - 1; - bn_limit_bits_low = low; - bn_limit_num_low = 1 << low; - } - if (mont >= 0) { - if (mont > (int)(sizeof(int) * 8) - 1) - mont = sizeof(int) * 8 - 1; - bn_limit_bits_mont = mont; - bn_limit_num_mont = 1 << mont; - } -} - -int BN_get_params(int which) -{ - if (which == 0) - return (bn_limit_bits); - else if (which == 1) - return (bn_limit_bits_high); - else if (which == 2) - return (bn_limit_bits_low); - else if (which == 3) - return (bn_limit_bits_mont); - else - return (0); -} -#endif - -const BIGNUM *BN_value_one(void) -{ - static const BN_ULONG data_one = 1L; - static const BIGNUM const_one = - { (BN_ULONG *)&data_one, 1, 1, 0, BN_FLG_STATIC_DATA }; - - return (&const_one); -} - -int 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(SIXTY_FOUR_BIT_LONG) - 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 -#else -# ifdef SIXTY_FOUR_BIT - if (l & 0xffffffff00000000LL) { - if (l & 0xffff000000000000LL) { - if (l & 0xff00000000000000LL) { - return (bits[(int)(l >> 56)] + 56); - } else - return (bits[(int)(l >> 48)] + 48); - } else { - if (l & 0x0000ff0000000000LL) { - return (bits[(int)(l >> 40)] + 40); - } else - return (bits[(int)(l >> 32)] + 32); - } - } else -# endif -#endif - { -#if defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG) - if (l & 0xffff0000L) { - if (l & 0xff000000L) - return (bits[(int)(l >> 24L)] + 24); - else - return (bits[(int)(l >> 16L)] + 16); - } else -#endif - { -#if defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG) - if (l & 0xff00L) - return (bits[(int)(l >> 8)] + 8); - else -#endif - return (bits[(int)(l)]); - } - } -} - -int BN_num_bits(const BIGNUM *a) -{ - int i = a->top - 1; - bn_check_top(a); - - if (BN_is_zero(a)) - return 0; - return ((i * BN_BITS2) + BN_num_bits_word(a->d[i])); -} - -void BN_clear_free(BIGNUM *a) -{ - int i; - - if (a == NULL) - return; - bn_check_top(a); - if (a->d != NULL) { - OPENSSL_cleanse(a->d, a->dmax * sizeof(a->d[0])); - if (!(BN_get_flags(a, BN_FLG_STATIC_DATA))) - OPENSSL_free(a->d); - } - i = BN_get_flags(a, BN_FLG_MALLOCED); - OPENSSL_cleanse(a, sizeof(BIGNUM)); - if (i) - OPENSSL_free(a); -} - -void BN_free(BIGNUM *a) -{ - if (a == NULL) - return; - bn_check_top(a); - if ((a->d != NULL) && !(BN_get_flags(a, BN_FLG_STATIC_DATA))) - OPENSSL_free(a->d); - if (a->flags & BN_FLG_MALLOCED) - OPENSSL_free(a); - else { -#ifndef OPENSSL_NO_DEPRECATED - a->flags |= BN_FLG_FREE; -#endif - a->d = NULL; - } -} - -void BN_init(BIGNUM *a) -{ - memset(a, 0, sizeof(BIGNUM)); - bn_check_top(a); -} - -BIGNUM *BN_new(void) -{ - BIGNUM *ret; - - if ((ret = (BIGNUM *)OPENSSL_malloc(sizeof(BIGNUM))) == NULL) { - BNerr(BN_F_BN_NEW, ERR_R_MALLOC_FAILURE); - return (NULL); - } - ret->flags = BN_FLG_MALLOCED; - ret->top = 0; - ret->neg = 0; - ret->dmax = 0; - ret->d = NULL; - bn_check_top(ret); - return (ret); -} - -/* This is used both by bn_expand2() and bn_dup_expand() */ -/* The caller MUST check that words > b->dmax before calling this */ -static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) -{ - BN_ULONG *A, *a = NULL; - const BN_ULONG *B; - int i; - - bn_check_top(b); - - if (words > (INT_MAX / (4 * BN_BITS2))) { - BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_BIGNUM_TOO_LONG); - return NULL; - } - if (BN_get_flags(b, BN_FLG_STATIC_DATA)) { - BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_EXPAND_ON_STATIC_BIGNUM_DATA); - return (NULL); - } - a = A = (BN_ULONG *)OPENSSL_malloc(sizeof(BN_ULONG) * words); - if (A == NULL) { - BNerr(BN_F_BN_EXPAND_INTERNAL, ERR_R_MALLOC_FAILURE); - return (NULL); - } -#ifdef PURIFY - /* - * Valgrind complains in BN_consttime_swap because we process the whole - * array even if it's not initialised yet. This doesn't matter in that - * function - what's important is constant time operation (we're not - * actually going to use the data) - */ - memset(a, 0, sizeof(BN_ULONG) * words); -#endif - -#if 1 - B = b->d; - /* Check if the previous number needs to be copied */ - if (B != NULL) { - for (i = b->top >> 2; i > 0; i--, A += 4, B += 4) { - /* - * The fact that the loop is unrolled - * 4-wise is a tribute to Intel. It's - * the one that doesn't have enough - * registers to accomodate more data. - * I'd unroll it 8-wise otherwise:-) - * - * <appro@fy.chalmers.se> - */ - BN_ULONG a0, a1, a2, a3; - a0 = B[0]; - a1 = B[1]; - a2 = B[2]; - a3 = B[3]; - A[0] = a0; - A[1] = a1; - A[2] = a2; - A[3] = a3; - } - /* - * workaround for ultrix cc: without 'case 0', the optimizer does - * the switch table by doing a=top&3; a--; goto jump_table[a]; - * which fails for top== 0 - */ - switch (b->top & 3) { - case 3: - A[2] = B[2]; - case 2: - A[1] = B[1]; - case 1: - A[0] = B[0]; - case 0: - ; - } - } -#else - memset(A, 0, sizeof(BN_ULONG) * words); - memcpy(A, b->d, sizeof(b->d[0]) * b->top); -#endif - - return (a); -} - -/* - * This is an internal function that can be used instead of bn_expand2() when - * there is a need to copy BIGNUMs instead of only expanding the data part, - * while still expanding them. Especially useful when needing to expand - * BIGNUMs that are declared 'const' and should therefore not be changed. The - * reason to use this instead of a BN_dup() followed by a bn_expand2() is - * memory allocation overhead. A BN_dup() followed by a bn_expand2() will - * allocate new memory for the BIGNUM data twice, and free it once, while - * bn_dup_expand() makes sure allocation is made only once. - */ - -#ifndef OPENSSL_NO_DEPRECATED -BIGNUM *bn_dup_expand(const BIGNUM *b, int words) -{ - BIGNUM *r = NULL; - - bn_check_top(b); - - /* - * This function does not work if words <= b->dmax && top < words because - * BN_dup() does not preserve 'dmax'! (But bn_dup_expand() is not used - * anywhere yet.) - */ - - if (words > b->dmax) { - BN_ULONG *a = bn_expand_internal(b, words); - - if (a) { - r = BN_new(); - if (r) { - r->top = b->top; - r->dmax = words; - r->neg = b->neg; - r->d = a; - } else { - /* r == NULL, BN_new failure */ - OPENSSL_free(a); - } - } - /* - * If a == NULL, there was an error in allocation in - * bn_expand_internal(), and NULL should be returned - */ - } else { - r = BN_dup(b); - } - - bn_check_top(r); - return r; -} -#endif - -/* - * This is an internal function that should not be used in applications. It - * ensures that 'b' has enough room for a 'words' word number and initialises - * any unused part of b->d with leading zeros. It is mostly used by the - * various BIGNUM routines. If there is an error, NULL is returned. If not, - * 'b' is returned. - */ - -BIGNUM *bn_expand2(BIGNUM *b, int words) -{ - bn_check_top(b); - - if (words > b->dmax) { - BN_ULONG *a = bn_expand_internal(b, words); - if (!a) - return NULL; - if (b->d) - OPENSSL_free(b->d); - b->d = a; - b->dmax = words; - } - -/* None of this should be necessary because of what b->top means! */ -#if 0 - /* - * NB: bn_wexpand() calls this only if the BIGNUM really has to grow - */ - if (b->top < b->dmax) { - int i; - BN_ULONG *A = &(b->d[b->top]); - for (i = (b->dmax - b->top) >> 3; i > 0; i--, A += 8) { - A[0] = 0; - A[1] = 0; - A[2] = 0; - A[3] = 0; - A[4] = 0; - A[5] = 0; - A[6] = 0; - A[7] = 0; - } - for (i = (b->dmax - b->top) & 7; i > 0; i--, A++) - A[0] = 0; - assert(A == &(b->d[b->dmax])); - } -#endif - bn_check_top(b); - return b; -} - -BIGNUM *BN_dup(const BIGNUM *a) -{ - BIGNUM *t; - - if (a == NULL) - return NULL; - bn_check_top(a); - - t = BN_new(); - if (t == NULL) - return NULL; - if (!BN_copy(t, a)) { - BN_free(t); - return NULL; - } - bn_check_top(t); - return t; -} - -BIGNUM *BN_copy(BIGNUM *a, const BIGNUM *b) -{ - int i; - BN_ULONG *A; - const BN_ULONG *B; - - bn_check_top(b); - - if (a == b) - return (a); - if (bn_wexpand(a, b->top) == NULL) - return (NULL); - -#if 1 - A = a->d; - B = b->d; - for (i = b->top >> 2; i > 0; i--, A += 4, B += 4) { - BN_ULONG a0, a1, a2, a3; - a0 = B[0]; - a1 = B[1]; - a2 = B[2]; - a3 = B[3]; - A[0] = a0; - A[1] = a1; - A[2] = a2; - A[3] = a3; - } - /* ultrix cc workaround, see comments in bn_expand_internal */ - switch (b->top & 3) { - case 3: - A[2] = B[2]; - case 2: - A[1] = B[1]; - case 1: - A[0] = B[0]; - case 0:; - } -#else - memcpy(a->d, b->d, sizeof(b->d[0]) * b->top); -#endif - - a->top = b->top; - a->neg = b->neg; - bn_check_top(a); - return (a); -} - -void BN_swap(BIGNUM *a, BIGNUM *b) -{ - int flags_old_a, flags_old_b; - BN_ULONG *tmp_d; - int tmp_top, tmp_dmax, tmp_neg; - - bn_check_top(a); - bn_check_top(b); - - flags_old_a = a->flags; - flags_old_b = b->flags; - - tmp_d = a->d; - tmp_top = a->top; - tmp_dmax = a->dmax; - tmp_neg = a->neg; - - a->d = b->d; - a->top = b->top; - a->dmax = b->dmax; - a->neg = b->neg; - - b->d = tmp_d; - b->top = tmp_top; - b->dmax = tmp_dmax; - b->neg = tmp_neg; - - a->flags = - (flags_old_a & BN_FLG_MALLOCED) | (flags_old_b & BN_FLG_STATIC_DATA); - b->flags = - (flags_old_b & BN_FLG_MALLOCED) | (flags_old_a & BN_FLG_STATIC_DATA); - bn_check_top(a); - bn_check_top(b); -} - -void BN_clear(BIGNUM *a) -{ - bn_check_top(a); - if (a->d != NULL) - OPENSSL_cleanse(a->d, a->dmax * sizeof(a->d[0])); - a->top = 0; - a->neg = 0; -} - -BN_ULONG BN_get_word(const BIGNUM *a) -{ - if (a->top > 1) - return BN_MASK2; - else if (a->top == 1) - return a->d[0]; - /* a->top == 0 */ - return 0; -} - -int BN_set_word(BIGNUM *a, BN_ULONG w) -{ - bn_check_top(a); - if (bn_expand(a, (int)sizeof(BN_ULONG) * 8) == NULL) - return (0); - a->neg = 0; - a->d[0] = w; - a->top = (w ? 1 : 0); - bn_check_top(a); - return (1); -} - -BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret) -{ - unsigned int i, m; - unsigned int n; - BN_ULONG l; - BIGNUM *bn = NULL; - - if (ret == NULL) - ret = bn = BN_new(); - if (ret == NULL) - return (NULL); - bn_check_top(ret); - l = 0; - n = len; - if (n == 0) { - ret->top = 0; - return (ret); - } - i = ((n - 1) / BN_BYTES) + 1; - m = ((n - 1) % (BN_BYTES)); - if (bn_wexpand(ret, (int)i) == NULL) { - if (bn) - BN_free(bn); - return NULL; - } - ret->top = i; - ret->neg = 0; - while (n--) { - l = (l << 8L) | *(s++); - if (m-- == 0) { - ret->d[--i] = l; - l = 0; - m = BN_BYTES - 1; - } - } - /* - * need to call this due to clear byte at top if avoiding having the top - * bit set (-ve number) - */ - bn_correct_top(ret); - return (ret); -} - -/* ignore negative */ -int BN_bn2bin(const BIGNUM *a, unsigned char *to) -{ - int n, i; - BN_ULONG l; - - bn_check_top(a); - n = i = BN_num_bytes(a); - while (i--) { - l = a->d[i / BN_BYTES]; - *(to++) = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff; - } - return (n); -} - -int BN_ucmp(const BIGNUM *a, const BIGNUM *b) -{ - int i; - BN_ULONG t1, t2, *ap, *bp; - - bn_check_top(a); - bn_check_top(b); - - 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); - } - - bn_check_top(a); - bn_check_top(b); - - if (a->neg != b->neg) { - if (a->neg) - return (-1); - else - 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_set_bit(BIGNUM *a, int n) -{ - int i, j, k; - - if (n < 0) - return 0; - - i = n / BN_BITS2; - j = n % BN_BITS2; - if (a->top <= i) { - if (bn_wexpand(a, i + 1) == NULL) - return (0); - for (k = a->top; k < i + 1; k++) - a->d[k] = 0; - a->top = i + 1; - } - - a->d[i] |= (((BN_ULONG)1) << j); - bn_check_top(a); - return (1); -} - -int BN_clear_bit(BIGNUM *a, int n) -{ - int i, j; - - bn_check_top(a); - if (n < 0) - return 0; - - i = n / BN_BITS2; - j = n % BN_BITS2; - if (a->top <= i) - return (0); - - a->d[i] &= (~(((BN_ULONG)1) << j)); - bn_correct_top(a); - return (1); -} - -int BN_is_bit_set(const BIGNUM *a, int n) -{ - int i, j; - - bn_check_top(a); - if (n < 0) - return 0; - i = n / BN_BITS2; - j = n % BN_BITS2; - if (a->top <= i) - return 0; - return (int)(((a->d[i]) >> j) & ((BN_ULONG)1)); -} - -int BN_mask_bits(BIGNUM *a, int n) -{ - int b, w; - - bn_check_top(a); - if (n < 0) - return 0; - - w = n / BN_BITS2; - b = n % BN_BITS2; - if (w >= a->top) - return 0; - if (b == 0) - a->top = w; - else { - a->top = w + 1; - a->d[w] &= ~(BN_MASK2 << b); - } - bn_correct_top(a); - return (1); -} - -void BN_set_negative(BIGNUM *a, int b) -{ - if (b && !BN_is_zero(a)) - a->neg = 1; - else - a->neg = 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); -} - -/* - * Here follows a specialised variants of bn_cmp_words(). It has the - * property of performing the operation on arrays of different sizes. The - * sizes of those arrays is expressed through cl, which is the common length - * ( basicall, min(len(a),len(b)) ), and dl, which is the delta between the - * two lengths, calculated as len(a)-len(b). All lengths are the number of - * BN_ULONGs... - */ - -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); -} - -/* - * Constant-time conditional swap of a and b. - * a and b are swapped if condition is not 0. The code assumes that at most one bit of condition is set. - * nwords is the number of words to swap. The code assumes that at least nwords are allocated in both a and b, - * and that no more than nwords are used by either a or b. - * a and b cannot be the same number - */ -void BN_consttime_swap(BN_ULONG condition, BIGNUM *a, BIGNUM *b, int nwords) -{ - BN_ULONG t; - int i; - - bn_wcheck_size(a, nwords); - bn_wcheck_size(b, nwords); - - assert(a != b); - assert((condition & (condition - 1)) == 0); - assert(sizeof(BN_ULONG) >= sizeof(int)); - - condition = ((condition - 1) >> (BN_BITS2 - 1)) - 1; - - t = (a->top ^ b->top) & condition; - a->top ^= t; - b->top ^= t; - -#define BN_CONSTTIME_SWAP(ind) \ - do { \ - t = (a->d[ind] ^ b->d[ind]) & condition; \ - a->d[ind] ^= t; \ - b->d[ind] ^= t; \ - } while (0) - - switch (nwords) { - default: - for (i = 10; i < nwords; i++) - BN_CONSTTIME_SWAP(i); - /* Fallthrough */ - case 10: - BN_CONSTTIME_SWAP(9); /* Fallthrough */ - case 9: - BN_CONSTTIME_SWAP(8); /* Fallthrough */ - case 8: - BN_CONSTTIME_SWAP(7); /* Fallthrough */ - case 7: - BN_CONSTTIME_SWAP(6); /* Fallthrough */ - case 6: - BN_CONSTTIME_SWAP(5); /* Fallthrough */ - case 5: - BN_CONSTTIME_SWAP(4); /* Fallthrough */ - case 4: - BN_CONSTTIME_SWAP(3); /* Fallthrough */ - case 3: - BN_CONSTTIME_SWAP(2); /* Fallthrough */ - case 2: - BN_CONSTTIME_SWAP(1); /* Fallthrough */ - case 1: - BN_CONSTTIME_SWAP(0); - } -#undef BN_CONSTTIME_SWAP -} |