diff options
Diffstat (limited to 'main/openssl/crypto/bn/bn_lib.c')
| m--------- | main/openssl | 0 | ||||
| -rw-r--r-- | main/openssl/crypto/bn/bn_lib.c | 887 |
2 files changed, 0 insertions, 887 deletions
diff --git a/main/openssl b/main/openssl new file mode 160000 +Subproject 4d377a9ce111930d8a8f06dc0e94a892a7f6c51 diff --git a/main/openssl/crypto/bn/bn_lib.c b/main/openssl/crypto/bn/bn_lib.c deleted file mode 100644 index d5a211e2..00000000 --- a/main/openssl/crypto/bn/bn_lib.c +++ /dev/null @@ -1,887 +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; - } - switch (b->top&3) - { - case 3: A[2]=B[2]; - case 2: A[1]=B[1]; - case 1: A[0]=B[0]; - case 0: /* 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 */ - ; - } - } - -#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; - } - switch (b->top&3) - { - case 3: A[2]=B[2]; - case 2: A[1]=B[1]; - case 1: A[0]=B[0]; - case 0: ; /* ultrix cc workaround, see comments in bn_expand_internal */ - } -#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) - memset(a->d,0,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 -} |