-/* crypto/bn/bn_lib.c */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
+/*
+ * Copyright 1995-2018 The OpenSSL Project Authors. 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.]
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
*/
-#ifndef BN_DEBUG
-# undef NDEBUG /* avoid conflicting definitions */
-# define NDEBUG
-#endif
-
#include <assert.h>
#include <limits.h>
-#include <stdio.h>
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
#include "bn_lcl.h"
+#include <openssl/opensslconf.h>
+#include "internal/constant_time_locl.h"
-const char *BN_version="Big Number" OPENSSL_VERSION_PTEXT;
-
-/* For a 32 bit machine
+/* This stuff appears to be completely unused, so is deprecated */
+#if OPENSSL_API_COMPAT < 0x00908000L
+/*-
+ * For a 32 bit machine
* 2 - 4 == 128
* 3 - 8 == 256
* 4 - 16 == 512
* 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) */
+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;
- }
- }
+{
+ 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);
- }
+{
+ 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 BN_ULONG data_one=1L;
- static BIGNUM const_one={&data_one,1,1,0};
-
- return(&const_one);
- }
-
-char *BN_options(void)
- {
- static int init=0;
- static char data[16];
-
- if (!init)
- {
- init++;
-#ifdef BN_LLONG
- sprintf(data,"bn(%d,%d)",(int)sizeof(BN_ULLONG)*8,
- (int)sizeof(BN_ULONG)*8);
-#else
- sprintf(data,"bn(%d,%d)",(int)sizeof(BN_ULONG)*8,
- (int)sizeof(BN_ULONG)*8);
-#endif
- }
- return(data);
- }
+{
+ 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 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
+{
+ BN_ULONG x, mask;
+ int bits = (l != 0);
+
+#if BN_BITS2 > 32
+ x = l >> 32;
+ mask = (0 - x) & BN_MASK2;
+ mask = (0 - (mask >> (BN_BITS2 - 1)));
+ bits += 32 & mask;
+ l ^= (x ^ l) & mask;
#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(SIXTEEN_BIT) || 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 )] );
- }
- }
- }
+
+ x = l >> 16;
+ mask = (0 - x) & BN_MASK2;
+ mask = (0 - (mask >> (BN_BITS2 - 1)));
+ bits += 16 & mask;
+ l ^= (x ^ l) & mask;
+
+ x = l >> 8;
+ mask = (0 - x) & BN_MASK2;
+ mask = (0 - (mask >> (BN_BITS2 - 1)));
+ bits += 8 & mask;
+ l ^= (x ^ l) & mask;
+
+ x = l >> 4;
+ mask = (0 - x) & BN_MASK2;
+ mask = (0 - (mask >> (BN_BITS2 - 1)));
+ bits += 4 & mask;
+ l ^= (x ^ l) & mask;
+
+ x = l >> 2;
+ mask = (0 - x) & BN_MASK2;
+ mask = (0 - (mask >> (BN_BITS2 - 1)));
+ bits += 2 & mask;
+ l ^= (x ^ l) & mask;
+
+ x = l >> 1;
+ mask = (0 - x) & BN_MASK2;
+ mask = (0 - (mask >> (BN_BITS2 - 1)));
+ bits += 1 & mask;
+
+ return bits;
+}
int BN_num_bits(const BIGNUM *a)
- {
- BN_ULONG l;
- int i;
+{
+ 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]));
+}
- bn_check_top(a);
+static void bn_free_d(BIGNUM *a)
+{
+ if (BN_get_flags(a, BN_FLG_SECURE))
+ OPENSSL_secure_free(a->d);
+ else
+ OPENSSL_free(a->d);
+}
- if (a->top == 0) return(0);
- l=a->d[a->top-1];
- assert(l != 0);
- i=(a->top-1)*BN_BITS2;
- return(i+BN_num_bits_word(l));
- }
void BN_clear_free(BIGNUM *a)
- {
- int i;
-
- if (a == NULL) return;
- 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);
- }
+{
+ if (a == NULL)
+ return;
+ if (a->d != NULL && !BN_get_flags(a, BN_FLG_STATIC_DATA)) {
+ OPENSSL_cleanse(a->d, a->dmax * sizeof(a->d[0]));
+ bn_free_d(a);
+ }
+ if (BN_get_flags(a, BN_FLG_MALLOCED)) {
+ OPENSSL_cleanse(a, sizeof(*a));
+ OPENSSL_free(a);
+ }
+}
void BN_free(BIGNUM *a)
- {
- if (a == NULL) return;
- if ((a->d != NULL) && !(BN_get_flags(a,BN_FLG_STATIC_DATA)))
- OPENSSL_free(a->d);
- a->flags|=BN_FLG_FREE; /* REMOVE? */
- if (a->flags & BN_FLG_MALLOCED)
- OPENSSL_free(a);
- }
-
-void BN_init(BIGNUM *a)
- {
- memset(a,0,sizeof(BIGNUM));
- }
+{
+ if (a == NULL)
+ return;
+ if (!BN_get_flags(a, BN_FLG_STATIC_DATA))
+ bn_free_d(a);
+ if (a->flags & BN_FLG_MALLOCED)
+ OPENSSL_free(a);
+}
+
+void bn_init(BIGNUM *a)
+{
+ static BIGNUM nilbn;
+
+ *a = nilbn;
+ 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;
- return(ret);
- }
-
-/* This is used both by bn_expand2() and bn_dup_expand() */
+{
+ BIGNUM *ret;
+
+ if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL) {
+ BNerr(BN_F_BN_NEW, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+ ret->flags = BN_FLG_MALLOCED;
+ bn_check_top(ret);
+ return ret;
+}
+
+ BIGNUM *BN_secure_new(void)
+ {
+ BIGNUM *ret = BN_new();
+ if (ret != NULL)
+ ret->flags |= BN_FLG_SECURE;
+ return ret;
+ }
+
+/* This is used by bn_expand2() */
/* 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;
-
- if (words > (INT_MAX/(4*BN_BITS2)))
- {
- BNerr(BN_F_BN_EXPAND_INTERNAL,BN_R_BIGNUM_TOO_LONG);
- return NULL;
- }
-
- bn_check_top(b);
- 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+1));
- if (A == NULL)
- {
- BNerr(BN_F_BN_EXPAND_INTERNAL,ERR_R_MALLOC_FAILURE);
- return(NULL);
- }
-#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+1));
- 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.
+{
+ BN_ULONG *a = NULL;
+
+ 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;
+ }
+ if (BN_get_flags(b, BN_FLG_SECURE))
+ a = OPENSSL_secure_zalloc(words * sizeof(*a));
+ else
+ a = OPENSSL_zalloc(words * sizeof(*a));
+ if (a == NULL) {
+ BNerr(BN_F_BN_EXPAND_INTERNAL, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+
+ assert(b->top <= words);
+ if (b->top > 0)
+ memcpy(a, b->d, sizeof(*a) * b->top);
+
+ return a;
+}
+
+/*
+ * 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_dup_expand(const BIGNUM *b, int words)
- {
- BIGNUM *r = NULL;
-
- /* 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);
- }
-
- return r;
- }
-
-/* 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_ULONG *A;
- int i;
-
- if (words > b->dmax)
- {
- BN_ULONG *a = bn_expand_internal(b, words);
-
- if (a)
- {
- if (b->d)
- OPENSSL_free(b->d);
- b->d=a;
- b->dmax=words;
- }
- else
- b = NULL;
- }
-
- /* NB: bn_wexpand() calls this only if the BIGNUM really has to grow */
- if ((b != NULL) && (b->top < b->dmax))
- {
- 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]));
- }
- return b;
- }
+{
+ if (words > b->dmax) {
+ BN_ULONG *a = bn_expand_internal(b, words);
+ if (!a)
+ return NULL;
+ if (b->d) {
+ OPENSSL_cleanse(b->d, b->dmax * sizeof(b->d[0]));
+ bn_free_d(b);
+ }
+ b->d = a;
+ b->dmax = words;
+ }
+
+ return b;
+}
BIGNUM *BN_dup(const BIGNUM *a)
- {
- BIGNUM *r, *t;
-
- if (a == NULL) return NULL;
-
- bn_check_top(a);
-
- t = BN_new();
- if (t == NULL) return(NULL);
- r = BN_copy(t, a);
- /* now r == t || r == NULL */
- if (r == NULL)
- BN_free(t);
- return r;
- }
+{
+ BIGNUM *t;
+
+ if (a == NULL)
+ return NULL;
+ bn_check_top(a);
+
+ t = BN_get_flags(a, BN_FLG_SECURE) ? BN_secure_new() : 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
-
-/* memset(&(a->d[b->top]),0,sizeof(a->d[0])*(a->max-b->top));*/
- a->top=b->top;
- if ((a->top == 0) && (a->d != NULL))
- a->d[0]=0;
- a->neg=b->neg;
- return(a);
- }
-
-BIGNUM *BN_ncopy(BIGNUM *a, const BIGNUM *b, size_t n)
- {
- int i, min;
- BN_ULONG *A;
- const BN_ULONG *B;
-
- bn_check_top(b);
-
- if (a == b)
- return a;
-
- min = (b->top < (int)n)? b->top: (int)n;
-
- if (!min)
- {
- BN_zero(a);
- return a;
- }
-
- if (bn_wexpand(a, min) == NULL)
- return NULL;
-
- A=a->d;
- B=b->d;
- for (i=min>>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 (min&3)
- {
- case 3: A[2]=B[2];
- case 2: A[1]=B[1];
- case 1: A[0]=B[0];
- case 0: ;
- }
- a->top = min;
-
- a->neg = b->neg;
- bn_fix_top(a);
-
- return(a);
- }
+{
+ bn_check_top(b);
+
+ if (a == b)
+ return a;
+ if (bn_wexpand(a, b->top) == NULL)
+ return NULL;
+
+ if (b->top > 0)
+ memcpy(a->d, b->d, sizeof(b->d[0]) * b->top);
+
+ a->neg = b->neg;
+ a->top = b->top;
+ a->flags |= b->flags & BN_FLG_FIXED_TOP;
+ bn_check_top(a);
+ return a;
+}
+
+#define FLAGS_DATA(flags) ((flags) & (BN_FLG_STATIC_DATA \
+ | BN_FLG_CONSTTIME \
+ | BN_FLG_SECURE \
+ | BN_FLG_FIXED_TOP))
+#define FLAGS_STRUCT(flags) ((flags) & (BN_FLG_MALLOCED))
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;
-
- 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);
- }
-
+{
+ 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_STRUCT(flags_old_a) | FLAGS_DATA(flags_old_b);
+ b->flags = FLAGS_STRUCT(flags_old_b) | FLAGS_DATA(flags_old_a);
+ bn_check_top(a);
+ bn_check_top(b);
+}
void BN_clear(BIGNUM *a)
- {
- if (a->d != NULL)
- memset(a->d,0,a->dmax*sizeof(a->d[0]));
- a->top=0;
- a->neg=0;
- }
+{
+ bn_check_top(a);
+ if (a->d != NULL)
+ OPENSSL_cleanse(a->d, sizeof(*a->d) * a->dmax);
+ a->neg = 0;
+ a->top = 0;
+ a->flags &= ~BN_FLG_FIXED_TOP;
+}
BN_ULONG BN_get_word(const BIGNUM *a)
- {
- int i,n;
- BN_ULONG ret=0;
-
- n=BN_num_bytes(a);
- if (n > (int)sizeof(BN_ULONG))
- return(BN_MASK2);
- for (i=a->top-1; i>=0; i--)
- {
-#ifndef SIXTY_FOUR_BIT /* the data item > unsigned long */
- ret<<=BN_BITS4; /* stops the compiler complaining */
- ret<<=BN_BITS4;
-#else
- ret=0;
-#endif
- ret|=a->d[i];
- }
- return(ret);
- }
+{
+ 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)
- {
- int i,n;
- if (bn_expand(a,(int)sizeof(BN_ULONG)*8) == NULL) return(0);
-
- n=sizeof(BN_ULONG)/BN_BYTES;
- a->neg=0;
- a->top=0;
- a->d[0]=(BN_ULONG)w&BN_MASK2;
- if (a->d[0] != 0) a->top=1;
- for (i=1; i<n; i++)
- {
- /* the following is done instead of
- * w>>=BN_BITS2 so compilers don't complain
- * on builds where sizeof(long) == BN_TYPES */
-#ifndef SIXTY_FOUR_BIT /* the data item > unsigned long */
- w>>=BN_BITS4;
- w>>=BN_BITS4;
-#else
- w=0;
-#endif
- a->d[i]=(BN_ULONG)w&BN_MASK2;
- if (a->d[i] != 0) a->top=i+1;
- }
- return(1);
- }
+{
+ 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);
+ a->flags &= ~BN_FLG_FIXED_TOP;
+ 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;
-
- if (ret == NULL) ret=BN_new();
- if (ret == NULL) return(NULL);
- l=0;
- n=len;
- if (n == 0)
- {
- ret->top=0;
- return(ret);
- }
- if (bn_expand(ret,(int)(n+2)*8) == NULL)
- return(NULL);
- i=((n-1)/BN_BYTES)+1;
- m=((n-1)%(BN_BYTES));
- ret->top=i;
- ret->neg=0;
- while (n-- > 0)
- {
- 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_fix_top(ret);
- return(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);
+ /* Skip leading zero's. */
+ for ( ; len > 0 && *s == 0; s++, len--)
+ continue;
+ 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) {
+ BN_free(bn);
+ return NULL;
+ }
+ ret->top = i;
+ ret->neg = 0;
+ l = 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 */
+static int bn2binpad(const BIGNUM *a, unsigned char *to, int tolen)
+{
+ int n;
+ size_t i, lasti, j, atop, mask;
+ BN_ULONG l;
+
+ /*
+ * In case |a| is fixed-top, BN_num_bytes can return bogus length,
+ * but it's assumed that fixed-top inputs ought to be "nominated"
+ * even for padded output, so it works out...
+ */
+ n = BN_num_bytes(a);
+ if (tolen == -1) {
+ tolen = n;
+ } else if (tolen < n) { /* uncommon/unlike case */
+ BIGNUM temp = *a;
+
+ bn_correct_top(&temp);
+ n = BN_num_bytes(&temp);
+ if (tolen < n)
+ return -1;
+ }
+
+ /* Swipe through whole available data and don't give away padded zero. */
+ atop = a->dmax * BN_BYTES;
+ if (atop == 0) {
+ OPENSSL_cleanse(to, tolen);
+ return tolen;
+ }
+
+ lasti = atop - 1;
+ atop = a->top * BN_BYTES;
+ for (i = 0, j = 0, to += tolen; j < (size_t)tolen; j++) {
+ l = a->d[i / BN_BYTES];
+ mask = 0 - ((j - atop) >> (8 * sizeof(i) - 1));
+ *--to = (unsigned char)(l >> (8 * (i % BN_BYTES)) & mask);
+ i += (i - lasti) >> (8 * sizeof(i) - 1); /* stay on last limb */
+ }
+
+ return tolen;
+}
+
+int BN_bn2binpad(const BIGNUM *a, unsigned char *to, int tolen)
+{
+ if (tolen < 0)
+ return -1;
+ return bn2binpad(a, to, tolen);
+}
+
int BN_bn2bin(const BIGNUM *a, unsigned char *to)
- {
- int n,i;
- BN_ULONG l;
-
- n=i=BN_num_bytes(a);
- while (i-- > 0)
- {
- l=a->d[i/BN_BYTES];
- *(to++)=(unsigned char)(l>>(8*(i%BN_BYTES)))&0xff;
- }
- return(n);
- }
+{
+ return bn2binpad(a, to, -1);
+}
+
+BIGNUM *BN_lebin2bn(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);
+ s += len;
+ /* Skip trailing zeroes. */
+ for ( ; len > 0 && s[-1] == 0; s--, len--)
+ continue;
+ 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) {
+ BN_free(bn);
+ return NULL;
+ }
+ ret->top = i;
+ ret->neg = 0;
+ l = 0;
+ while (n--) {
+ s--;
+ 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;
+}
+
+int BN_bn2lebinpad(const BIGNUM *a, unsigned char *to, int tolen)
+{
+ int i;
+ BN_ULONG l;
+ bn_check_top(a);
+ i = BN_num_bytes(a);
+ if (tolen < i)
+ return -1;
+ /* Add trailing zeroes if necessary */
+ if (tolen > i)
+ memset(to + i, 0, tolen - i);
+ to += i;
+ while (i--) {
+ l = a->d[i / BN_BYTES];
+ to--;
+ *to = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff;
+ }
+ return tolen;
+}
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 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 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;
-
- 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);
- return(1);
- }
+{
+ 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->flags &= ~BN_FLG_FIXED_TOP;
+ }
+
+ a->d[i] |= (((BN_ULONG)1) << j);
+ bn_check_top(a);
+ return 1;
+}
int BN_clear_bit(BIGNUM *a, int n)
- {
- int i,j;
+{
+ int i, j;
- i=n/BN_BITS2;
- j=n%BN_BITS2;
- if (a->top <= i) return(0);
+ bn_check_top(a);
+ if (n < 0)
+ return 0;
- a->d[i]&=(~(((BN_ULONG)1)<<j));
- bn_fix_top(a);
- return(1);
- }
+ i = n / BN_BITS2;
+ j = n % BN_BITS2;
+ if (a->top <= i)
+ return 0;
-int BN_is_bit_set(const BIGNUM *a, int n)
- {
- int i,j;
+ a->d[i] &= (~(((BN_ULONG)1) << j));
+ bn_correct_top(a);
+ return 1;
+}
- if (n < 0) return(0);
- i=n/BN_BITS2;
- j=n%BN_BITS2;
- if (a->top <= i) return(0);
- return((a->d[i]&(((BN_ULONG)1)<<j))?1:0);
- }
+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;
-
- 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_fix_top(a);
- return(1);
- }
+{
+ 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);
- }
+{
+ 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
+ * capability of performing the operation on arrays of different sizes. The
+ * sizes of those arrays is expressed through cl, which is the common length
+ * ( basically, 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;
+
+ t = (a->neg ^ b->neg) & condition;
+ a->neg ^= t;
+ b->neg ^= t;
+
+ /*-
+ * BN_FLG_STATIC_DATA: indicates that data may not be written to. Intention
+ * is actually to treat it as it's read-only data, and some (if not most)
+ * of it does reside in read-only segment. In other words observation of
+ * BN_FLG_STATIC_DATA in BN_consttime_swap should be treated as fatal
+ * condition. It would either cause SEGV or effectively cause data
+ * corruption.
+ *
+ * BN_FLG_MALLOCED: refers to BN structure itself, and hence must be
+ * preserved.
+ *
+ * BN_FLG_SECURE: must be preserved, because it determines how x->d was
+ * allocated and hence how to free it.
+ *
+ * BN_FLG_CONSTTIME: sufficient to mask and swap
+ *
+ * BN_FLG_FIXED_TOP: indicates that we haven't called bn_correct_top() on
+ * the data, so the d array may be padded with additional 0 values (i.e.
+ * top could be greater than the minimal value that it could be). We should
+ * be swapping it
+ */
+
+#define BN_CONSTTIME_SWAP_FLAGS (BN_FLG_CONSTTIME | BN_FLG_FIXED_TOP)
+
+ t = ((a->flags ^ b->flags) & BN_CONSTTIME_SWAP_FLAGS) & condition;
+ a->flags ^= t;
+ b->flags ^= 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
+}
+
+/* Bits of security, see SP800-57 */
+
+int BN_security_bits(int L, int N)
+{
+ int secbits, bits;
+ if (L >= 15360)
+ secbits = 256;
+ else if (L >= 7680)
+ secbits = 192;
+ else if (L >= 3072)
+ secbits = 128;
+ else if (L >= 2048)
+ secbits = 112;
+ else if (L >= 1024)
+ secbits = 80;
+ else
+ return 0;
+ if (N == -1)
+ return secbits;
+ bits = N / 2;
+ if (bits < 80)
+ return 0;
+ return bits >= secbits ? secbits : bits;
+}
+
+void BN_zero_ex(BIGNUM *a)
+{
+ a->neg = 0;
+ a->top = 0;
+ a->flags &= ~BN_FLG_FIXED_TOP;
+}
+
+int BN_abs_is_word(const BIGNUM *a, const BN_ULONG w)
+{
+ return ((a->top == 1) && (a->d[0] == w)) || ((w == 0) && (a->top == 0));
+}
+
+int BN_is_zero(const BIGNUM *a)
+{
+ return a->top == 0;
+}
+
+int BN_is_one(const BIGNUM *a)
+{
+ return BN_abs_is_word(a, 1) && !a->neg;
+}
+
+int BN_is_word(const BIGNUM *a, const BN_ULONG w)
+{
+ return BN_abs_is_word(a, w) && (!w || !a->neg);
+}
+
+int BN_is_odd(const BIGNUM *a)
+{
+ return (a->top > 0) && (a->d[0] & 1);
+}
+
+int BN_is_negative(const BIGNUM *a)
+{
+ return (a->neg != 0);
+}
+
+int BN_to_montgomery(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont,
+ BN_CTX *ctx)
+{
+ return BN_mod_mul_montgomery(r, a, &(mont->RR), mont, ctx);
+}
+
+void BN_with_flags(BIGNUM *dest, const BIGNUM *b, int flags)
+{
+ dest->d = b->d;
+ dest->top = b->top;
+ dest->dmax = b->dmax;
+ dest->neg = b->neg;
+ dest->flags = ((dest->flags & BN_FLG_MALLOCED)
+ | (b->flags & ~BN_FLG_MALLOCED)
+ | BN_FLG_STATIC_DATA | flags);
+}
+
+BN_GENCB *BN_GENCB_new(void)
+{
+ BN_GENCB *ret;
+
+ if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) {
+ BNerr(BN_F_BN_GENCB_NEW, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+
+ return ret;
+}
+
+void BN_GENCB_free(BN_GENCB *cb)
+{
+ if (cb == NULL)
+ return;
+ OPENSSL_free(cb);
+}
+
+void BN_set_flags(BIGNUM *b, int n)
+{
+ b->flags |= n;
+}
+
+int BN_get_flags(const BIGNUM *b, int n)
+{
+ return b->flags & n;
+}
+
+/* Populate a BN_GENCB structure with an "old"-style callback */
+void BN_GENCB_set_old(BN_GENCB *gencb, void (*callback) (int, int, void *),
+ void *cb_arg)
+{
+ BN_GENCB *tmp_gencb = gencb;
+ tmp_gencb->ver = 1;
+ tmp_gencb->arg = cb_arg;
+ tmp_gencb->cb.cb_1 = callback;
+}
+
+/* Populate a BN_GENCB structure with a "new"-style callback */
+void BN_GENCB_set(BN_GENCB *gencb, int (*callback) (int, int, BN_GENCB *),
+ void *cb_arg)
+{
+ BN_GENCB *tmp_gencb = gencb;
+ tmp_gencb->ver = 2;
+ tmp_gencb->arg = cb_arg;
+ tmp_gencb->cb.cb_2 = callback;
+}
+
+void *BN_GENCB_get_arg(BN_GENCB *cb)
+{
+ return cb->arg;
+}
+
+BIGNUM *bn_wexpand(BIGNUM *a, int words)
+{
+ return (words <= a->dmax) ? a : bn_expand2(a, words);
+}
+
+void bn_correct_top(BIGNUM *a)
+{
+ BN_ULONG *ftl;
+ int tmp_top = a->top;
+
+ if (tmp_top > 0) {
+ for (ftl = &(a->d[tmp_top]); tmp_top > 0; tmp_top--) {
+ ftl--;
+ if (*ftl != 0)
+ break;
+ }
+ a->top = tmp_top;
+ }
+ if (a->top == 0)
+ a->neg = 0;
+ a->flags &= ~BN_FLG_FIXED_TOP;
+ bn_pollute(a);
+}
projects / openssl.git / blobdiff