diff options
| -rw-r--r-- | src/cm/cm_any.h | 10 | ||||
| -rw-r--r-- | src/cm/cm_prime.c | 56 |
2 files changed, 17 insertions, 49 deletions
diff --git a/src/cm/cm_any.h b/src/cm/cm_any.h index c2ab350..eb54497 100644 --- a/src/cm/cm_any.h +++ b/src/cm/cm_any.h @@ -15,6 +15,16 @@ typedef struct { /** * @brief * @param order + * @param d + * @param p + * @param ord_prime + * @return + */ +GEN cm_construct_curve(GEN order, GEN d, GEN p, bool ord_prime); + +/** + * @brief + * @param order * @return */ curve_t *cm_any_curve(GEN order); diff --git a/src/cm/cm_prime.c b/src/cm/cm_prime.c index 267b8c1..c7a931d 100644 --- a/src/cm/cm_prime.c +++ b/src/cm/cm_prime.c @@ -3,6 +3,7 @@ * Copyright (C) 2017-2018 J08nY */ #include "cm_prime.h" +#include "cm_any.h" #include "io/output.h" #include "obj/curve.h" #include "obj/point.h" @@ -137,69 +138,26 @@ static void qdisc_next(cm_prime_qdisc_t *qdisc) { static void qdisc_free(cm_prime_qdisc_t *qdisc) { try_free(qdisc->Sp); } curve_t *cm_prime_curve(GEN order) { - GEN a = NULL; - GEN b = NULL; GEN e = NULL; - GEN g = NULL; cm_prime_qdisc_t qdisc; qdisc_init(&qdisc, order); - while (true) { + do { qdisc_next(&qdisc); - - debug_log("order = %Pi", order); - debug_log("p = %Pi, t = %Pi, D = %Pi, ", qdisc.p, qdisc.t, qdisc.D); - GEN H = polclass(qdisc.D, 0, 0); - - debug_log("H = %Ps", H); - - GEN r = FpX_roots(H, qdisc.p); - debug_log("roots = %Ps", r); - if (gequal(r, gtovec(gen_0))) { - continue; - } - - bool has_curve = false; - - long rlen = glength(r); - for (long i = 1; i <= rlen; ++i) { - GEN root = gel(r, i); - a = mkintmod( - Fp_div( - Fp_mul(stoi(27), root, qdisc.p), - Fp_mul(stoi(4), Fp_sub(stoi(1728), root, qdisc.p), qdisc.p), - qdisc.p), - qdisc.p); - b = gneg(a); - e = ellinit(mkvec2(a, b), qdisc.p, 0); - pari_CATCH(e_TYPE) { continue; } - pari_TRY { checkell(e); }; - pari_ENDCATCH{}; - - g = genrand(e); - GEN gmul = ellmul(e, g, order); - if (ell_is_inf(gmul)) { - debug_log("YES %Ps", e); - has_curve = true; - break; - } - } - - if (has_curve) break; - } - + e = cm_construct_curve(order, qdisc.D, qdisc.p, true); + } while (e == NULL); qdisc_free(&qdisc); curve_t *result = curve_new(); result->field = qdisc.p; - result->a = a; - result->b = b; + result->a = ell_get_a4(e); + result->b = ell_get_a6(e); result->curve = e; result->order = order; result->generators = subgroups_new(1); result->generators[0] = subgroup_new(); result->generators[0]->generator = point_new(); - result->generators[0]->generator->point = g; + result->generators[0]->generator->point = genrand(e); result->generators[0]->generator->order = order; result->generators[0]->generator->cofactor = stoi(1); result->generators[0]->npoints = 0; |