diff options
| -rw-r--r-- | mpi/mpih-const-time.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/mpi/mpih-const-time.c b/mpi/mpih-const-time.c index 5ebb8d11..96899505 100644 --- a/mpi/mpih-const-time.c +++ b/mpi/mpih-const-time.c @@ -170,12 +170,13 @@ _gcry_mpih_mod (mpi_ptr_t vp, mpi_size_t vsize, mpi_limb_t limb = vp[limbno]; unsigned int the_bit = ((limb & (A_LIMB_1 << bitno)) ? 1 : 0); mpi_limb_t underflow; + mpi_limb_t overflow; - _gcry_mpih_lshift (rp, rp, usize, 1); + overflow = _gcry_mpih_lshift (rp, rp, usize, 1); rp[0] |= the_bit; underflow = _gcry_mpih_sub_n (rp, rp, up, usize); - mpih_add_n_cond (rp, rp, up, usize, underflow); + mpih_add_n_cond (rp, rp, up, usize, overflow ^ underflow); } return rp; |