/* -*-c-*-
*
- * $Id: ec-prime.c,v 1.8 2004/03/27 17:54:11 mdw Exp $
+ * $Id: ec-prime.c,v 1.9 2004/04/01 12:50:09 mdw Exp $
*
* Elliptic curves over prime fields
*
/*----- Revision history --------------------------------------------------*
*
* $Log: ec-prime.c,v $
+ * Revision 1.9 2004/04/01 12:50:09 mdw
+ * Add cyclic group abstraction, with test code. Separate off exponentation
+ * functions for better static linking. Fix a buttload of bugs on the way.
+ * Generally ensure that negative exponents do inversion correctly. Add
+ * table of standard prime-field subgroups. (Binary field subgroups are
+ * currently unimplemented but easy to add if anyone ever finds a good one.)
+ *
* Revision 1.8 2004/03/27 17:54:11 mdw
* Standard curves and curve checking.
*
static int eccheck(ec_curve *c, const ec *p)
{
field *f = c->f;
+ mp *l, *x, *r;
int rc;
- mp *l = F_SQR(f, MP_NEW, p->y);
- mp *x = F_SQR(f, MP_NEW, p->x);
- mp *r = F_MUL(f, MP_NEW, x, p->x);
+ if (EC_ATINF(p)) return (0);
+ l = F_SQR(f, MP_NEW, p->y);
+ x = F_SQR(f, MP_NEW, p->x);
+ r = F_MUL(f, MP_NEW, x, p->x);
x = F_MUL(f, x, c->a, p->x);
r = F_ADD(f, r, r, x);
r = F_ADD(f, r, r, c->b);
}
static const ec_ops ec_primeops = {
- ecdestroy, ec_idin, ec_idout, ec_idfix,
+ ecdestroy, ec_stdsamep, ec_idin, ec_idout, ec_idfix,
ecfind, ecneg, ecadd, ec_stdsub, ecdbl, eccheck
};
static const ec_ops ec_primeprojops = {
- ecdestroy, ec_projin, ec_projout, ec_projfix,
+ ecdestroy, ec_stdsamep, ec_projin, ec_projout, ec_projfix,
ecfind, ecneg, ecprojadd, ec_stdsub, ecprojdbl, ecprojcheck
};
static const ec_ops ec_primeprojxops = {
- ecdestroy, ec_projin, ec_projout, ec_projfix,
+ ecdestroy, ec_stdsamep, ec_projin, ec_projout, ec_projfix,
ecfind, ecneg, ecprojadd, ec_stdsub, ecprojxdbl, ecprojcheck
};