static val_ptr run_extend(val_ptr v[]) {
// TODO: Check v[1] is multiz poly.
field_ptr fx = (field_ptr)pbc_malloc(sizeof(*fx));
field_init_poly(fx, v[0]->field);
element_ptr poly = element_new(fx);
element_set_multiz(poly, (multiz)(v[1]->elem->data));
field_ptr f = (field_ptr)pbc_malloc(sizeof(*f));
field_init_polymod(f, poly);
element_free(poly);
return val_new_field(f);
}
void pbc_param_init_d_gen(pbc_param_ptr p, pbc_cm_ptr cm) {
d_param_init(p);
d_param_ptr param = p->data;
field_t Fq, Fqx, Fqd;
element_t irred, nqr;
int d = cm->k / 2;
int i;
compute_cm_curve(param, cm);
field_init_fp(Fq, param->q);
field_init_poly(Fqx, Fq);
element_init(irred, Fqx);
do {
poly_random_monic(irred, d);
} while (!poly_is_irred(irred));
field_init_polymod(Fqd, irred);
// Find a quadratic nonresidue of Fqd lying in Fq.
element_init(nqr, Fqd);
do {
element_random(((element_t *) nqr->data)[0]);
} while (element_is_sqr(nqr));
param->coeff = pbc_realloc(param->coeff, sizeof(mpz_t) * d);
for (i=0; i<d; i++) {
mpz_init(param->coeff[i]);
element_to_mpz(param->coeff[i], element_item(irred, i));
}
element_to_mpz(param->nqr, ((element_t *) nqr->data)[0]);
element_clear(nqr);
element_clear(irred);
field_clear(Fqx);
field_clear(Fqd);
field_clear(Fq);
}
static val_ptr run_polymod(val_ptr v[]) {
// TODO: Check v[0] is a poly.
field_ptr f = (field_ptr)pbc_malloc(sizeof(*f));
field_init_polymod(f, v[0]->elem);
return val_new_field(f);
}
static void f_init_pairing(pairing_t pairing, void *data) {
f_param_ptr param = data;
f_pairing_data_ptr p;
element_t irred;
element_t e0, e1, e2;
p = pairing->data = pbc_malloc(sizeof(f_pairing_data_t));
mpz_init(pairing->r);
mpz_set(pairing->r, param->r);
field_init_fp(pairing->Zr, pairing->r);
field_init_fp(p->Fq, param->q);
p->Fq->nqr = pbc_malloc(sizeof(element_t));
element_init(p->Fq->nqr, p->Fq);
element_set_mpz(p->Fq->nqr, param->beta);
field_init_quadratic(p->Fq2, p->Fq);
field_init_poly(p->Fq2x, p->Fq2);
element_init(irred, p->Fq2x);
// Call poly_set_coeff1() first so we can use element_item() for the other
// coefficients.
poly_set_coeff1(irred, 6);
element_init(p->negalpha, p->Fq2);
element_init(p->negalphainv, p->Fq2);
element_set_mpz(element_x(p->negalpha), param->alpha0);
element_set_mpz(element_y(p->negalpha), param->alpha1);
element_set(element_item(irred, 0), p->negalpha);
field_init_polymod(p->Fq12, irred);
element_neg(p->negalpha, p->negalpha);
element_invert(p->negalphainv, p->negalpha);
element_clear(irred);
element_init(e0, p->Fq);
element_init(e1, p->Fq);
element_init(e2, p->Fq2);
// Initialize the curve Y^2 = X^3 + b.
element_set_mpz(e1, param->b);
field_init_curve_ab(p->Eq, e0, e1, pairing->r, NULL);
// Initialize the curve Y^2 = X^3 - alpha0 b - alpha1 sqrt(beta) b.
element_set_mpz(e0, param->alpha0);
element_neg(e0, e0);
element_mul(element_x(e2), e0, e1);
element_set_mpz(e0, param->alpha1);
element_neg(e0, e0);
element_mul(element_y(e2), e0, e1);
element_clear(e0);
element_init(e0, p->Fq2);
field_init_curve_ab(p->Etwist, e0, e2, pairing->r, NULL);
element_clear(e0);
element_clear(e1);
element_clear(e2);
mpz_t ndonr;
mpz_init(ndonr);
// ndonr temporarily holds the trace.
mpz_sub(ndonr, param->q, param->r);
mpz_add_ui(ndonr, ndonr, 1);
// TODO: We can use a smaller quotient_cmp, but I have to figure out
// BN curves again.
pbc_mpz_curve_order_extn(ndonr, param->q, ndonr, 12);
mpz_divexact(ndonr, ndonr, param->r);
mpz_divexact(ndonr, ndonr, param->r);
field_curve_set_quotient_cmp(p->Etwist, ndonr);
mpz_clear(ndonr);
pairing->G1 = p->Eq;
pairing->G2 = p->Etwist;
pairing_GT_init(pairing, p->Fq12);
pairing->finalpow = f_finalpow;
pairing->map = f_pairing;
pairing->clear_func = f_pairing_clear;
mpz_init(p->tateexp);
/* unoptimized tate exponent
mpz_pow_ui(p->tateexp, param->q, 12);
mpz_sub_ui(p->tateexp, p->tateexp, 1);
mpz_divexact(p->tateexp, p->tateexp, param->r);
*/
mpz_ptr z = p->tateexp;
mpz_mul(z, param->q, param->q);
mpz_sub_ui(z, z, 1);
mpz_mul(z, z, param->q);
mpz_mul(z, z, param->q);
mpz_add_ui(z, z, 1);
mpz_divexact(z, z, param->r);
element_init(p->xpowq2, p->Fq2);
element_init(p->xpowq6, p->Fq2);
element_init(p->xpowq8, p->Fq2);
element_t xpowq;
element_init(xpowq, p->Fq12);
//there are smarter ways since we know q = 1 mod 6
//and that x^6 = -alpha
//but this is fast enough
element_set1(element_item(xpowq, 1));
element_pow_mpz(xpowq, xpowq, param->q);
element_pow_mpz(xpowq, xpowq, param->q);
element_set(p->xpowq2, element_item(xpowq, 1));
element_pow_mpz(xpowq, xpowq, param->q);
element_pow_mpz(xpowq, xpowq, param->q);
element_pow_mpz(xpowq, xpowq, param->q);
element_pow_mpz(xpowq, xpowq, param->q);
element_set(p->xpowq6, element_item(xpowq, 1));
element_pow_mpz(xpowq, xpowq, param->q);
element_pow_mpz(xpowq, xpowq, param->q);
element_set(p->xpowq8, element_item(xpowq, 1));
element_clear(xpowq);
}
static void d_init_pairing(pairing_ptr pairing, void *data) {
d_param_ptr param = data;
pptr p;
element_t a, b;
element_t irred;
int d = param->k / 2;
int i;
if (param->k % 2) pbc_die("k must be even");
mpz_init(pairing->r);
mpz_set(pairing->r, param->r);
field_init_fp(pairing->Zr, pairing->r);
pairing->map = cc_pairing;
pairing->prod_pairings = cc_pairings_affine;
pairing->is_almost_coddh = cc_is_almost_coddh;
p = pairing->data = pbc_malloc(sizeof(*p));
field_init_fp(p->Fq, param->q);
element_init(a, p->Fq);
element_init(b, p->Fq);
element_set_mpz(a, param->a);
element_set_mpz(b, param->b);
field_init_curve_ab(p->Eq, a, b, pairing->r, param->h);
field_init_poly(p->Fqx, p->Fq);
element_init(irred, p->Fqx);
poly_set_coeff1(irred, d);
for (i = 0; i < d; i++) {
element_set_mpz(element_item(irred, i), param->coeff[i]);
}
field_init_polymod(p->Fqd, irred);
element_clear(irred);
p->Fqd->nqr = pbc_malloc(sizeof(element_t));
element_init(p->Fqd->nqr, p->Fqd);
element_set_mpz(((element_t *) p->Fqd->nqr->data)[0], param->nqr);
field_init_quadratic(p->Fqk, p->Fqd);
// Compute constants involved in the final powering.
if (param->k == 6) {
mpz_ptr q = param->q;
mpz_ptr z = pairing->phikonr;
mpz_init(z);
mpz_mul(z, q, q);
mpz_sub(z, z, q);
mpz_add_ui(z, z, 1);
mpz_divexact(z, z, pairing->r);
element_ptr e = p->xpowq;
element_init(e, p->Fqd);
element_set1(((element_t *) e->data)[1]);
element_pow_mpz(e, e, q);
element_init(p->xpowq2, p->Fqd);
element_square(p->xpowq2, e);
} else {
mpz_init(p->tateexp);
mpz_sub_ui(p->tateexp, p->Fqk->order, 1);
mpz_divexact(p->tateexp, p->tateexp, pairing->r);
}
field_init_curve_ab_map(p->Etwist, p->Eq, element_field_to_polymod, p->Fqd, pairing->r, NULL);
field_reinit_curve_twist(p->Etwist);
mpz_t ndonr;
mpz_init(ndonr);
// ndonr temporarily holds the trace.
mpz_sub(ndonr, param->q, param->n);
mpz_add_ui(ndonr, ndonr, 1);
// Negate it because we want the trace of the twist.
mpz_neg(ndonr, ndonr);
pbc_mpz_curve_order_extn(ndonr, param->q, ndonr, d);
mpz_divexact(ndonr, ndonr, param->r);
field_curve_set_quotient_cmp(p->Etwist, ndonr);
mpz_clear(ndonr);
element_init(p->nqrinv, p->Fqd);
element_invert(p->nqrinv, field_get_nqr(p->Fqd));
element_init(p->nqrinv2, p->Fqd);
element_square(p->nqrinv2, p->nqrinv);
pairing->G1 = p->Eq;
pairing->G2 = p->Etwist;
p->k = param->k;
pairing_GT_init(pairing, p->Fqk);
pairing->finalpow = cc_finalpow;
// By default use affine coordinates.
cc_miller_no_denom_fn = cc_miller_no_denom_affine;
pairing->option_set = d_pairing_option_set;
pairing->pp_init = d_pairing_pp_init;
pairing->pp_clear = d_pairing_pp_clear;
pairing->pp_apply = d_pairing_pp_apply;
pairing->clear_func = d_pairing_clear;
element_clear(a);
element_clear(b);
}