diff options
| -rw-r--r-- | mpi/mpih-const-time.c | 7 | ||||
| -rw-r--r-- | mpi/mpiutil.c | 23 |
2 files changed, 18 insertions, 12 deletions
diff --git a/mpi/mpih-const-time.c b/mpi/mpih-const-time.c index 8b78aabc..3a69e6ba 100644 --- a/mpi/mpih-const-time.c +++ b/mpi/mpih-const-time.c @@ -40,13 +40,12 @@ _gcry_mpih_set_cond (mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned long op_enable) { mpi_size_t i; - mpi_limb_t mask = ((mpi_limb_t)0) - op_enable; - mpi_limb_t x; + mpi_limb_t mask1 = vzero - op_enable; + mpi_limb_t mask2 = op_enable - vone; for (i = 0; i < usize; i++) { - x = mask & (wp[i] ^ up[i]); - wp[i] = wp[i] ^ x; + wp[i] = (wp[i] & mask2) | (up[i] & mask1); } } diff --git a/mpi/mpiutil.c b/mpi/mpiutil.c index a1ac1c43..5320f4d8 100644 --- a/mpi/mpiutil.c +++ b/mpi/mpiutil.c @@ -519,23 +519,30 @@ _gcry_mpi_set_cond (gcry_mpi_t w, const gcry_mpi_t u, unsigned long set) { mpi_size_t i; mpi_size_t nlimbs = u->alloced; - mpi_limb_t mask = ((mpi_limb_t)0) - set; - mpi_limb_t x; + mpi_limb_t mask1 = vzero - set; + mpi_limb_t mask2 = set - vone; + mpi_limb_t xu; + mpi_limb_t xw; + mpi_limb_t *uu = u->d; + mpi_limb_t *uw = w->d; if (w->alloced != u->alloced) log_bug ("mpi_set_cond: different sizes\n"); for (i = 0; i < nlimbs; i++) { - x = mask & (w->d[i] ^ u->d[i]); - w->d[i] = w->d[i] ^ x; + xu = uu[i]; + xw = uw[i]; + uw[i] = (xw & mask2) | (xu & mask1); } - x = mask & (w->nlimbs ^ u->nlimbs); - w->nlimbs = w->nlimbs ^ x; + xu = u->nlimbs; + xw = w->nlimbs; + w->nlimbs = (xw & mask2) | (xu & mask1); - x = mask & (w->sign ^ u->sign); - w->sign = w->sign ^ x; + xu = u->sign; + xw = w->sign; + w->sign = (xw & mask2) | (xu & mask1); return w; } |