void field_init_curve_b(field_ptr f, element_ptr b, mpz_t order, mpz_t cofac) {
element_t a;
element_init(a, b->field);
field_init_curve_ab(f, a, b, order, cofac);
element_clear(a);
}
void field_init_curve_ab_map(field_t cnew, field_t c,
fieldmap map, field_ptr mapdest,
mpz_t ordernew, mpz_t cofacnew) {
element_t a, b;
curve_data_ptr cdp = (curve_data_ptr)c->data;
element_init(a, mapdest);
element_init(b, mapdest);
map(a, cdp->a);
map(b, cdp->b);
field_init_curve_ab(cnew, a, b, ordernew, cofacnew);
element_clear(a);
element_clear(b);
}
// Requires j != 0, 1728.
void field_init_curve_j(field_ptr f, element_ptr j, mpz_t order, mpz_t cofac) {
element_t a, b;
element_init(a, j->field);
element_init(b, j->field);
element_set_si(a, 1728);
element_sub(a, a, j);
element_invert(a, a);
element_mul(a, a, j);
//b = 2 j / (1728 - j)
element_add(b, a, a);
//a = 3 j / (1728 - j)
element_add(a, a, b);
field_init_curve_ab(f, a, b, order, cofac);
element_clear(a);
element_clear(b);
}
static void e_init_pairing(pairing_t pairing, void *data) {
e_param_ptr param = data;
e_pairing_data_ptr p;
element_t a, b;
mpz_init(pairing->r);
mpz_set(pairing->r, param->r);
field_init_fp(pairing->Zr, pairing->r);
pairing->map = e_pairing;
e_miller_fn = e_miller_proj;
p = pairing->data = pbc_malloc(sizeof(e_pairing_data_t));
p->exp2 = param->exp2;
p->exp1 = param->exp1;
p->sign1 = param->sign1;
p->sign0 = param->sign0;
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);
//k=1, hence phikonr = (p-1)/r
mpz_init(pairing->phikonr);
mpz_sub_ui(pairing->phikonr, p->Fq->order, 1);
mpz_divexact(pairing->phikonr, pairing->phikonr, pairing->r);
pairing->G2 = pairing->G1 = p->Eq;
pairing_GT_init(pairing, p->Fq);
pairing->finalpow = e_finalpow;
pairing->phi = phi_identity;
pairing->option_set = e_pairing_option_set;
pairing->clear_func = e_pairing_clear;
element_init(p->R, p->Eq);
curve_set_gen_no_cofac(p->R);
element_clear(a);
element_clear(b);
}
int main(void) {
field_t c;
field_t Z19;
element_t P, Q, R;
mpz_t q, z;
element_t a, b;
int i;
field_t Z19_2;
field_t c2;
element_t P2, Q2, R2;
element_t a2;
mpz_init(q);
mpz_init(z);
mpz_set_ui(q, 19);
field_init_fp(Z19, q);
element_init(a, Z19);
element_init(b, Z19);
element_set_si(a, 1);
element_set_si(b, 6);
mpz_set_ui(q, 18);
field_init_curve_ab(c, a, b, q, NULL);
element_init(P, c);
element_init(Q, c);
element_init(R, c);
printf("Y^2 = X^3 + X + 6 over F_19\n");
//(0,+/-5) is a generator
element_set0(a);
curve_from_x(R, a);
for (i=1; i<19; i++) {
mpz_set_si(z, i);
element_mul_mpz(Q, R, z);
element_printf("%dR = %B\n", i, Q);
}
mpz_set_ui(z, 6);
element_mul_mpz(P, R, z);
//P has order 3
element_printf("P = %B\n", P);
for (i=1; i<=3; i++) {
mpz_set_si(z, i);
element_mul_mpz(Q, R, z);
tate_3(a, P, Q, R);
element_printf("e_3(P,%dR) = %B\n", i, a);
}
element_double(P, R);
//P has order 9
element_printf("P = %B\n", P);
for (i=1; i<=9; i++) {
mpz_set_si(z, i);
//we're supposed to use multiples of R
//but 2R works just as well and it allows us
//to use R as the offset every time
element_mul_mpz(Q, P, z);
tate_9(a, P, Q, R);
element_printf("e_9(P,%dP) = %B\n", i, a);
}
//to do the pairing on all of E(F_19) we need to move to F_19^2
//or compute the rational function explicitly
printf("moving to F_19^2\n");
field_init_fi(Z19_2, Z19);
//don't need to tell it the real order
field_init_curve_ab_map(c2, c, element_field_to_fi, Z19_2, q, NULL);
element_init(P2, c2);
element_init(Q2, c2);
element_init(R2, c2);
element_init(a2, Z19_2);
element_set0(a2);
curve_from_x(P2, a2);
element_random(R2);
element_printf("P = %B\n", P2);
for (i=1; i<=18; i++) {
mpz_set_si(z, i);
element_mul_mpz(Q2, P2, z);
tate_18(a2, P2, Q2, R2, P2);
element_printf("e_18(P,%dP) = %B\n", i, a2);
}
element_clear(P2);
element_clear(Q2);
element_clear(R2);
element_clear(a2);
field_clear(c2);
field_clear(Z19_2);
field_clear(c);
element_clear(a);
element_clear(b);
element_clear(P);
element_clear(Q);
element_clear(R);
field_clear(Z19);
mpz_clear(q);
mpz_clear(z);
return 0;
}
int main(void)
{
int i;
element_t g, h;
element_t w0, w1;
element_t a, b;
mpz_t prime, cofac;
mpz_init(prime);
mpz_init(order);
mpz_init(cofac);
mpz_set_ui(prime, 59);
field_init_fp(Fq, prime);
element_init(a, Fq);
element_init(b, Fq);
field_init_fi(Fq2, Fq);
element_set1(a);
element_set0(b);
mpz_set_ui(order, 5);
mpz_set_ui(cofac, 12);
field_init_curve_ab(E, a, b, order, cofac);
element_clear(a);
element_clear(b);
element_init(a, Fq2);
element_init(b, Fq2);
element_set1(a);
element_set0(b);
mpz_mul(cofac, cofac, cofac);
field_init_curve_ab(E2, a, b, order, NULL);
element_init(g, E2);
element_init(h, E2);
element_init(w0, Fq2);
element_init(w1, Fq2);
/*
do {
element_random(g);
} while (element_is1(g));
for (i=1; i<5; i++) {
element_mul(h, h, g);
element_printf("%d: %B\n", i, h);
element_printf("tangent = ");
do_tangent(h);
}
*/
element_set_str(g, "[[25,0],[30,0]", 0);
element_set_str(h, "[[34,0],[0,30]", 0);
weil(w0, g, h);
element_printf("weil: %B\n", w0);
element_set1(w1);
for (i=1; i<6; i++) {
element_mul(w1, w1, w0);
element_printf("%d: %B\n", i, w1);
}
fasterweil(w0, g, h);
element_printf("fasterweil: %B\n", w0);
element_set1(w1);
for (i=1; i<6; i++) {
element_mul(w1, w1, w0);
element_printf("%d: %B\n", i, w1);
}
fasterweil2(w0, g, h);
element_printf("fasterweil2: %B\n", w0);
tate(w0, g, h);
element_printf("tate: %B\n", w0);
element_set1(w1);
for (i=1; i<6; i++) {
element_mul(w1, w1, w0);
element_printf("%d: %B\n", i, w1);
}
shipseystange(w0, g, h);
element_printf("ss-tate: %B\n", w0);
element_set1(w1);
for (i=1; i<6; i++) {
element_mul(w1, w1, w0);
element_printf("%d: %B\n", i, w1);
}
return 0;
}
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);
}
