diff options
| -rw-r--r-- | networking/tls_sp_c32.c | 58 |
1 files changed, 22 insertions, 36 deletions
diff --git a/networking/tls_sp_c32.c b/networking/tls_sp_c32.c index d3bb36a..ffcb83d 100644 --- a/networking/tls_sp_c32.c +++ b/networking/tls_sp_c32.c @@ -626,68 +626,54 @@ static void sp_256_map_10(sp_point* r, sp_point* p, sp_digit* t) */ static void sp_256_proj_point_dbl_10(sp_point* r, sp_point* p, sp_digit* t) { - sp_point *rp[2]; sp_point tp; sp_digit* t1 = t; sp_digit* t2 = t + 2*10; - sp_digit* x; - sp_digit* y; - sp_digit* z; - int i; - /* When infinity don't double point passed in - constant time. */ - rp[0] = r; - rp[1] = &tp; - x = rp[p->infinity]->x; - y = rp[p->infinity]->y; - z = rp[p->infinity]->z; - /* Put point to double into result - good for infinity. */ - if (r != p) { - for (i = 0; i < 10; i++) - r->x[i] = p->x[i]; - for (i = 0; i < 10; i++) - r->y[i] = p->y[i]; - for (i = 0; i < 10; i++) - r->z[i] = p->z[i]; - r->infinity = p->infinity; - } + /* Put point to double into result */ + if (r != p) + *r = *p; /* struct copy */ + if (r->infinity) { + /* If infinity, don't double (work on dummy value) */ + r = &tp; + } /* T1 = Z * Z */ - sp_256_mont_sqr_10(t1, z, p256_mod, p256_mp_mod); + sp_256_mont_sqr_10(t1, r->z, p256_mod, p256_mp_mod); /* Z = Y * Z */ - sp_256_mont_mul_10(z, y, z, p256_mod, p256_mp_mod); + sp_256_mont_mul_10(r->z, r->y, r->z, p256_mod, p256_mp_mod); /* Z = 2Z */ - sp_256_mont_dbl_10(z, z, p256_mod); + sp_256_mont_dbl_10(r->z, r->z, p256_mod); /* T2 = X - T1 */ - sp_256_mont_sub_10(t2, x, t1, p256_mod); + sp_256_mont_sub_10(t2, r->x, t1, p256_mod); /* T1 = X + T1 */ - sp_256_mont_add_10(t1, x, t1, p256_mod); + sp_256_mont_add_10(t1, r->x, t1, p256_mod); /* T2 = T1 * T2 */ sp_256_mont_mul_10(t2, t1, t2, p256_mod, p256_mp_mod); /* T1 = 3T2 */ sp_256_mont_tpl_10(t1, t2, p256_mod); /* Y = 2Y */ - sp_256_mont_dbl_10(y, y, p256_mod); + sp_256_mont_dbl_10(r->y, r->y, p256_mod); /* Y = Y * Y */ - sp_256_mont_sqr_10(y, y, p256_mod, p256_mp_mod); + sp_256_mont_sqr_10(r->y, r->y, p256_mod, p256_mp_mod); /* T2 = Y * Y */ - sp_256_mont_sqr_10(t2, y, p256_mod, p256_mp_mod); + sp_256_mont_sqr_10(t2, r->y, p256_mod, p256_mp_mod); /* T2 = T2/2 */ sp_256_div2_10(t2, t2, p256_mod); /* Y = Y * X */ - sp_256_mont_mul_10(y, y, x, p256_mod, p256_mp_mod); + sp_256_mont_mul_10(r->y, r->y, r->x, p256_mod, p256_mp_mod); /* X = T1 * T1 */ - sp_256_mont_mul_10(x, t1, t1, p256_mod, p256_mp_mod); + sp_256_mont_mul_10(r->x, t1, t1, p256_mod, p256_mp_mod); /* X = X - Y */ - sp_256_mont_sub_10(x, x, y, p256_mod); + sp_256_mont_sub_10(r->x, r->x, r->y, p256_mod); /* X = X - Y */ - sp_256_mont_sub_10(x, x, y, p256_mod); + sp_256_mont_sub_10(r->x, r->x, r->y, p256_mod); /* Y = Y - X */ - sp_256_mont_sub_10(y, y, x, p256_mod); + sp_256_mont_sub_10(r->y, r->y, r->x, p256_mod); /* Y = Y * T1 */ - sp_256_mont_mul_10(y, y, t1, p256_mod, p256_mp_mod); + sp_256_mont_mul_10(r->y, r->y, t1, p256_mod, p256_mp_mod); /* Y = Y - T2 */ - sp_256_mont_sub_10(y, y, t2, p256_mod); + sp_256_mont_sub_10(r->y, r->y, t2, p256_mod); } /* Add two Montgomery form projective points. |