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| author | NIIBE Yutaka <gniibe@fsij.org> | 2017-08-23 10:22:21 +0900 |
|---|---|---|
| committer | NIIBE Yutaka <gniibe@fsij.org> | 2017-08-23 10:22:21 +0900 |
| commit | aeca1f0afc9091dab9fe1f018ea600064531ccf0 (patch) | |
| tree | a09d438a7a39c0c3b4836d16ac6173597bcfd03c | |
| parent | 02444ab2addeaf9b41aa1bed82cfc7b1ca67404f (diff) | |
| download | libgcrypt-aeca1f0afc9091dab9fe1f018ea600064531ccf0.tar.gz | |
ecc: Fix ec_mulm_25519.
* mpi/ec.c (ec_mulm_25519): Fix the cases of 0 to 18.
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
| -rw-r--r-- | mpi/ec.c | 5 |
1 files changed, 5 insertions, 0 deletions
@@ -479,6 +479,11 @@ ec_mulm_25519 (gcry_mpi_t w, gcry_mpi_t u, gcry_mpi_t v, mpi_ec_t ctx) m[0] = (cy * 2 + msb) * 19; _gcry_mpih_add_n (wp, wp, m, wsize); wp[LIMB_SIZE_25519-1] &= ~(1UL << (255 % BITS_PER_MPI_LIMB)); + + m[0] = 0; + cy = _gcry_mpih_sub_n (wp, wp, ctx->p->d, wsize); + mpih_set_cond (m, ctx->p->d, wsize, (cy != 0UL)); + _gcry_mpih_add_n (wp, wp, m, wsize); } static void |