From: Daiki Ueno dueno@redhat.com
This allows the same code to be reused in curve448 and Ed448.
Signed-off-by: Daiki Ueno dueno@redhat.com --- ecc-eh-to-a.c | 2 +- eddsa-sign.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/ecc-eh-to-a.c b/ecc-eh-to-a.c index 2acaacb1..b9d412d2 100644 --- a/ecc-eh-to-a.c +++ b/ecc-eh-to-a.c @@ -73,7 +73,7 @@ ecc_eh_to_a (const struct ecc_curve *ecc, at all? Full reduction mod p is maybe sufficient. */ unsigned shift; assert (ecc->p.bit_size == 255); - shift = 252 - GMP_NUMB_BITS * (ecc->p.size - 1); + shift = ecc->q.bit_size - 1 - GMP_NUMB_BITS * (ecc->p.size - 1); cy = mpn_submul_1 (r, ecc->q.m, ecc->p.size, r[ecc->p.size-1] >> shift); assert (cy < 2); diff --git a/eddsa-sign.c b/eddsa-sign.c index c1404f67..e5dc0e9d 100644 --- a/eddsa-sign.c +++ b/eddsa-sign.c @@ -92,7 +92,7 @@ _eddsa_sign (const struct ecc_curve *ecc, unsigned shift; mp_limb_t cy; assert (ecc->p.bit_size == 255); - shift = 252 - GMP_NUMB_BITS * (ecc->p.size - 1); + shift = ecc->q.bit_size - 1 - GMP_NUMB_BITS * (ecc->p.size - 1); cy = mpn_submul_1 (sp, ecc->q.m, ecc->p.size, sp[ecc->p.size-1] >> shift); assert (cy < 2);