# 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;
+const char BN_version[]="Big Number" OPENSSL_VERSION_PTEXT;
/* This stuff appears to be completely unused, so is deprecated */
#ifndef OPENSSL_NO_DEPRECATED
const BIGNUM *BN_value_one(void)
{
- static BN_ULONG data_one=1L;
- static BIGNUM const_one={&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);
}
-char *BN_options(void)
- {
- static int init=0;
- static char data[16];
-
- if (!init)
- {
- init++;
-#ifdef BN_LLONG
- BIO_snprintf(data,sizeof data,"bn(%d,%d)",
- (int)sizeof(BN_ULLONG)*8,(int)sizeof(BN_ULONG)*8);
-#else
- BIO_snprintf(data,sizeof data,"bn(%d,%d)",
- (int)sizeof(BN_ULONG)*8,(int)sizeof(BN_ULONG)*8);
-#endif
- }
- return(data);
- }
-
int BN_num_bits_word(BN_ULONG l)
{
- static const char bits[256]={
+ 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,
else
#endif
{
-#if defined(SIXTEEN_BIT) || defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG)
+#if defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG)
if (l & 0xff00L)
return(bits[(int)(l>>8)]+8);
else
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 */
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_correct_top(a);
- return(a);
- }
-
void BN_swap(BIGNUM *a, BIGNUM *b)
{
int flags_old_a, flags_old_b;
i=n/BN_BITS2;
j=n%BN_BITS2;
if (a->top <= i) return 0;
- return((a->d[i]&(((BN_ULONG)1)<<j))?1:0);
+ return (int)(((a->d[i])>>j)&((BN_ULONG)1));
}
int BN_mask_bits(BIGNUM *a, int n)
}
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
+}
+
+/* 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 >= 7690)
+ 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;
+ }
projects / openssl.git / blobdiff