Fix 0.9.8 FIPS capable OpenSSL build.

The object file bn_lib.o is excluded from FIPS builds which causes
a linker error for BN_consttime_swap. So move definition from bn_lib.c
to bn_gf2m.c

This change is *only* needed for OpenSSL 0.9.8 which uses the 1.2
FIPS module.
This commit is contained in:
Dr. Stephen Henson 2014-06-06 12:16:10 +01:00
parent bfce4e5d6e
commit 0a9b8dd1b4
2 changed files with 51 additions and 52 deletions

View File

@ -1095,3 +1095,54 @@ int BN_GF2m_arr2poly(const unsigned int p[], BIGNUM *a)
return 1;
}
/*
* 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
}

View File

@ -824,55 +824,3 @@ int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *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
}