int
ec2np_mul(ec2np_ptr d, ec2np_ptr a, b2n_ptr e, ec2ng_ptr g)
{
int i, j, bits, start;
b2n_t h, k;
ec2np_t q, mina;
if (!b2n_cmp_null(e)) {
d->inf = 1;
if (b2n_set_null(d->x))
return -1;
return b2n_set_null(d->y);
}
b2n_init(h);
b2n_init(k);
ec2np_init(q);
ec2np_init(mina);
if (ec2np_set(q, a))
goto fail;
/* Create the point -a. */
if (ec2np_set(mina, a))
goto fail;
if (b2n_add(mina->y, mina->y, mina->x))
goto fail;
if (b2n_set(k, e))
goto fail;
if (b2n_3mul(h, k))
goto fail;
if (b2n_resize(k, h->chunks))
goto fail;
/*
* This is low level but can not be avoided, since we have to do single
* bit checks on h and k.
*/
bits = b2n_sigbit(h);
if ((bits & CHUNK_MASK) == 1) {
start = ((CHUNK_MASK + bits) >> CHUNK_SHIFTS) - 2;
bits = CHUNK_BITS;
} else {
int
main (void)
{
b2n_t k;
ec2np_t p, q, r;
ec2ng_t g;
char buf[BUFSIZE];
b2n_init (k);
ec2np_init (p);
ec2np_init (q);
ec2np_init (r);
ec2ng_init (g);
printf ("Testing: ec2ng_set* :");
/* Init Group */
ec2ng_set_p_str (g, "0x0800000000000000000000004000000000000001");
CMP_FAIL (g->p, "0x0800000000000000000000004000000000000001");
ec2ng_set_a_ui (g, 0);
CMP_FAIL (g->a, "0x00");
ec2ng_set_b_str (g, "0x07338f");
CMP_FAIL (g->b, "0x07338f");
printf ("\nTesting: ec2np_find_y: ");
/* Init Point */
ec2np_set_x_ui (p, 0x7b);
ec2np_find_y (p, g);
CMP_FAIL (p->y, "0x01c8");
printf ("\nTesting: ec2np_ison: ");
if (ec2np_ison (p, g))
printf ("OKAY ");
else
printf ("FAILED ");
ec2np_set_x_ui (q, 0x4);
ec2np_find_y (q, g);
if (ec2np_ison (q, g))
printf ("OKAY ");
else
printf ("FAILED ");
printf ("\nTesting: ec2np_add: ");
ec2np_set (r, p);
b2n_add (r->y, r->y, r->x);
ec2np_add (r, r, p, g);
if (!r->inf)
printf ("FAILED ");
else
printf ("OKAY ");
ec2np_add (q, p, q, g);
CMP_FAIL (q->x, "0x06f32d7cc82cec8612a87a86e026350fb7595469");
CMP_FAIL (q->y, "0x4ab92e21e51358ca8deab3fbbc9f7d8a7d1575");
if (ec2np_ison (q, g))
printf ("OKAY ");
else
printf ("FAILED ");
ec2np_add (p, q, q, g);
CMP_FAIL (p->x, "0x0390001461385559a22ac9b6181c1e1889b38451");
CMP_FAIL (p->y, "0x0188e61f38d747d7813c6a8b33d14dfb7418b04c");
if (ec2np_ison (p, g))
printf ("OKAY ");
else
printf ("FAILED ");
printf ("\nTesting: ec2np_mul: ");
b2n_set_ui (k, 57);
ec2np_set (q, p);
ec2np_mul (q, q, k, g);
if (ec2np_ison (q, g))
printf ("OKAY ");
else
printf ("FAILED ");
CMP_FAIL (q->x, "0x06bcf88caab88f99399350c46559da3b91afbf9d");
b2n_set_str (k, "0x0800000000000000000057db5698537193aef943");
ec2np_set (q, p);
ec2np_mul (q, q, k, g);
if (ec2np_ison (q, g))
printf ("OKAY ");
else
printf ("FAILED ");
CMP_FAIL (q->x, "0x0390001461385559a22ac9b6181c1e1889b38451");
printf ("\n");
ec2np_clear (p);
ec2np_clear (q);
ec2np_clear (r);
ec2ng_clear (g);
b2n_clear (k);
return 1;
}
int
ec2np_add(ec2np_ptr d, ec2np_ptr a, ec2np_ptr b, ec2ng_ptr g)
{
b2n_t lambda, temp;
ec2np_t pn;
/* Check for Neutral Element */
if (b->inf)
return ec2np_set(d, a);
if (a->inf)
return ec2np_set(d, b);
if (!b2n_cmp(a->x, b->x) && (b2n_cmp(a->y, b->y) ||
!b2n_cmp_null(a->x))) {
d->inf = 1;
if (b2n_set_null(d->x))
return -1;
return b2n_set_null(d->y);
}
b2n_init(lambda);
b2n_init(temp);
ec2np_init(pn);
if (b2n_cmp(a->x, b->x)) {
if (b2n_add(temp, a->x, b->x))
goto fail;
if (b2n_add(lambda, a->y, b->y))
goto fail;
if (b2n_div_mod(lambda, lambda, temp, g->p))
goto fail;
if (b2n_square(pn->x, lambda))
goto fail;
if (b2n_mod(pn->x, pn->x, g->p))
goto fail;
if (b2n_add(pn->x, pn->x, lambda))
goto fail;
if (b2n_add(pn->x, pn->x, g->a))
goto fail;
if (b2n_add(pn->x, pn->x, a->x))
goto fail;
if (b2n_add(pn->x, pn->x, b->x))
goto fail;
} else {
if (b2n_div_mod(lambda, b->y, b->x, g->p))
goto fail;
if (b2n_add(lambda, lambda, b->x))
goto fail;
if (b2n_square(pn->x, lambda))
goto fail;
if (b2n_mod(pn->x, pn->x, g->p))
goto fail;
if (b2n_add(pn->x, pn->x, lambda))
goto fail;
if (b2n_add(pn->x, pn->x, g->a))
goto fail;
}
if (b2n_add(pn->y, b->x, pn->x))
goto fail;
if (b2n_mul(pn->y, pn->y, lambda))
goto fail;
if (b2n_mod(pn->y, pn->y, g->p))
goto fail;
if (b2n_add(pn->y, pn->y, pn->x))
goto fail;
if (b2n_add(pn->y, pn->y, b->y))
goto fail;
EC2NP_SWAP(d, pn);
ec2np_clear(pn);
b2n_clear(lambda);
b2n_clear(temp);
return 0;
fail:
ec2np_clear(pn);
b2n_clear(lambda);
b2n_clear(temp);
return -1;
}