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-rw-r--r--crypto/bn/bn_lib.c1437
1 files changed, 733 insertions, 704 deletions
diff --git a/crypto/bn/bn_lib.c b/crypto/bn/bn_lib.c
index d5a211e288b6..80105fff410c 100644
--- a/crypto/bn/bn_lib.c
+++ b/crypto/bn/bn_lib.c
@@ -5,21 +5,21 @@
* 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:
@@ -34,10 +34,10 @@
* 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
+ * 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
@@ -49,7 +49,7 @@
* 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
@@ -57,7 +57,7 @@
*/
#ifndef BN_DEBUG
-# undef NDEBUG /* avoid conflicting definitions */
+# undef NDEBUG /* avoid conflicting definitions */
# define NDEBUG
#endif
@@ -67,11 +67,12 @@
#include "cryptlib.h"
#include "bn_lcl.h"
-const char BN_version[]="Big Number" OPENSSL_VERSION_PTEXT;
+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
+/*-
+ * For a 32 bit machine
* 2 - 4 == 128
* 3 - 8 == 256
* 4 - 16 == 512
@@ -80,808 +81,836 @@ const char BN_version[]="Big Number" OPENSSL_VERSION_PTEXT;
* 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 const BN_ULONG data_one=1L;
- static const BIGNUM const_one={(BN_ULONG *)&data_one,1,1,0,BN_FLG_STATIC_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);
- }
+ 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,
- };
+{
+ 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
+ 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
+# 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
+ 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
+ if (l & 0xff00L)
+ return (bits[(int)(l >> 8)] + 8);
+ else
#endif
- return(bits[(int)(l )] );
- }
- }
- }
+ return (bits[(int)(l)]);
+ }
+ }
+}
int BN_num_bits(const BIGNUM *a)
- {
- int i = a->top - 1;
- bn_check_top(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]));
- }
+ 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);
- }
+{
+ 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
- {
+{
+ 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;
+ a->flags |= BN_FLG_FREE;
#endif
- a->d = NULL;
- }
- }
+ a->d = NULL;
+ }
+}
void BN_init(BIGNUM *a)
- {
- memset(a,0,sizeof(BIGNUM));
- bn_check_top(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);
- }
+{
+ 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);
- }
+{
+ 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);
+ /*
+ * 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 */
- ;
- }
- }
-
+ 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);
+ 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.
+
+ 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;
- }
+{
+ 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. */
+/*
+ * 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;
- }
+{
+ 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]));
- }
+ /*
+ * 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;
- }
+ 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 *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;
+{
+ int i;
+ BN_ULONG *A;
+ const BN_ULONG *B;
- bn_check_top(b);
+ bn_check_top(b);
- if (a == b) return(a);
- if (bn_wexpand(a,b->top) == NULL) return(NULL);
+ 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 */
- }
+ 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);
+ 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);
- }
+ 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);
- }
+{
+ 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_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;
- }
+{
+ 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);
- }
+{
+ 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);
- }
+{
+ 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 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 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;
-
- 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 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;
+{
+ int i, j;
- bn_check_top(a);
- if (n < 0) return 0;
+ bn_check_top(a);
+ if (n < 0)
+ return 0;
- i=n/BN_BITS2;
- j=n%BN_BITS2;
- if (a->top <= i) 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);
- }
+ 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 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);
- }
+{
+ 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;
- }
+{
+ 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.
+{
+ 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_ULONG t;
+ int i;
- bn_wcheck_size(a, nwords);
- bn_wcheck_size(b, nwords);
+ bn_wcheck_size(a, nwords);
+ bn_wcheck_size(b, nwords);
- assert(a != b);
- assert((condition & (condition - 1)) == 0);
- assert(sizeof(BN_ULONG) >= sizeof(int));
+ assert(a != b);
+ assert((condition & (condition - 1)) == 0);
+ assert(sizeof(BN_ULONG) >= sizeof(int));
- condition = ((condition - 1) >> (BN_BITS2 - 1)) - 1;
+ condition = ((condition - 1) >> (BN_BITS2 - 1)) - 1;
- t = (a->top^b->top) & condition;
- a->top ^= t;
- b->top ^= t;
+ 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);
- }
+ 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
}