diff options
Diffstat (limited to 'libtomcrypt/src/pk/ecc/ltc_ecc_projective_add_point.c')
| -rw-r--r-- | libtomcrypt/src/pk/ecc/ltc_ecc_projective_add_point.c | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/libtomcrypt/src/pk/ecc/ltc_ecc_projective_add_point.c b/libtomcrypt/src/pk/ecc/ltc_ecc_projective_add_point.c index c45a47b..9e22e10 100644 --- a/libtomcrypt/src/pk/ecc/ltc_ecc_projective_add_point.c +++ b/libtomcrypt/src/pk/ecc/ltc_ecc_projective_add_point.c @@ -5,8 +5,6 @@ * * The library is free for all purposes without any express * guarantee it works. - * - * Tom St Denis, tomstdenis@gmail.com, http://libtom.org */ /* Implements ECC over Z/pZ for curve y^2 = x^3 - 3x + b @@ -19,9 +17,9 @@ /** @file ltc_ecc_projective_add_point.c ECC Crypto, Tom St Denis -*/ +*/ -#if defined(LTC_MECC) && (!defined(LTC_MECC_ACCEL) || defined(LTM_LTC_DESC)) +#if defined(LTC_MECC) && (!defined(LTC_MECC_ACCEL) || defined(LTM_DESC)) /** Add two ECC points @@ -46,11 +44,11 @@ int ltc_ecc_projective_add_point(ecc_point *P, ecc_point *Q, ecc_point *R, void if ((err = mp_init_multi(&t1, &t2, &x, &y, &z, NULL)) != CRYPT_OK) { return err; } - + /* should we dbl instead? */ if ((err = mp_sub(modulus, Q->y, t1)) != CRYPT_OK) { goto done; } - if ( (mp_cmp(P->x, Q->x) == LTC_MP_EQ) && + if ( (mp_cmp(P->x, Q->x) == LTC_MP_EQ) && (Q->z != NULL && mp_cmp(P->z, Q->z) == LTC_MP_EQ) && (mp_cmp(P->y, Q->y) == LTC_MP_EQ || mp_cmp(P->y, t1) == LTC_MP_EQ)) { mp_clear_multi(t1, t2, x, y, z, NULL); @@ -144,7 +142,7 @@ int ltc_ecc_projective_add_point(ecc_point *P, ecc_point *Q, ecc_point *R, void /* T1 = T1 * X */ if ((err = mp_mul(t1, x, t1)) != CRYPT_OK) { goto done; } if ((err = mp_montgomery_reduce(t1, modulus, mp)) != CRYPT_OK) { goto done; } - + /* X = Y*Y */ if ((err = mp_sqr(y, x)) != CRYPT_OK) { goto done; } if ((err = mp_montgomery_reduce(x, modulus, mp)) != CRYPT_OK) { goto done; } @@ -158,7 +156,7 @@ int ltc_ecc_projective_add_point(ecc_point *P, ecc_point *Q, ecc_point *R, void if ((err = mp_sub(t2, x, t2)) != CRYPT_OK) { goto done; } if (mp_cmp_d(t2, 0) == LTC_MP_LT) { if ((err = mp_add(t2, modulus, t2)) != CRYPT_OK) { goto done; } - } + } /* T2 = T2 - X */ if ((err = mp_sub(t2, x, t2)) != CRYPT_OK) { goto done; } if (mp_cmp_d(t2, 0) == LTC_MP_LT) { @@ -190,7 +188,7 @@ done: #endif -/* $Source$ */ -/* $Revision$ */ -/* $Date$ */ +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */ |