/* -*-c-*-
*
- * $Id: ec-bin.c,v 1.5 2004/03/27 17:54:11 mdw Exp $
+ * $Id$
*
* Arithmetic for elliptic curves over binary fields
*
* (c) 2004 Straylight/Edgeware
*/
-/*----- Licensing notice --------------------------------------------------*
+/*----- Licensing notice --------------------------------------------------*
*
* This file is part of Catacomb.
*
* it under the terms of the GNU Library General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
- *
+ *
* Catacomb is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
- *
+ *
* You should have received a copy of the GNU Library General Public
* License along with Catacomb; if not, write to the Free
* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: ec-bin.c,v $
- * Revision 1.5 2004/03/27 17:54:11 mdw
- * Standard curves and curve checking.
- *
- * Revision 1.4 2004/03/23 15:19:32 mdw
- * Test elliptic curves more thoroughly.
- *
- * Revision 1.3 2004/03/22 02:19:09 mdw
- * Rationalise the sliding-window threshold. Drop guarantee that right
- * arguments to EC @add@ are canonical, and fix up projective implementations
- * to cope.
- *
- * Revision 1.2 2004/03/21 22:52:06 mdw
- * Merge and close elliptic curve branch.
- *
- * Revision 1.1.2.1 2004/03/21 22:39:46 mdw
- * Elliptic curves on binary fields work.
- *
- */
-
/*----- Header files ------------------------------------------------------*/
#include <mLib/sub.h>
#include "ec.h"
-
-/*----- Data structures ---------------------------------------------------*/
-
-typedef struct ecctx {
- ec_curve c;
- mp *bb;
-} ecctx;
+#include "ec-guts.h"
/*----- Main code ---------------------------------------------------------*/
{
field *f = c->f;
mp *y, *u, *v;
-
+
if (F_ZEROP(f, x))
y = F_SQRT(f, MP_NEW, c->b);
else {
EC_SETINF(d);
else {
field *f = c->f;
- ecctx *cc = (ecctx *)c;
+ ecctx_bin *cc = (ecctx_bin *)c;
mp *dx, *dy, *dz, *u, *v;
dy = F_SQR(f, MP_NEW, a->z); /* %$z^2$% */
d->z = dz;
MP_DROP(u);
MP_DROP(v);
- assert(!(d->x->f & MP_DESTROYED));
- assert(!(d->y->f & MP_DESTROYED));
- assert(!(d->z->f & MP_DESTROYED));
}
return (d);
}
dx = F_ADD(f, dx, dx, c->a); /* %$a + \lambda^2 + \lambda$% */
dx = F_ADD(f, dx, dx, a->x); /* %$a + \lambda^2 + \lambda + x_0$% */
dx = F_ADD(f, dx, dx, b->x);
- /* %$x' = a + \lambda^2 + \lambda + x_0 + x_1$% */
+ /* %$x' = a + \lambda^2 + \lambda + x_0 + x_1$% */
} else if (!MP_EQ(a->y, b->y) || F_ZEROP(f, a->x)) {
EC_SETINF(d);
return (d);
dx = F_ADD(f, dx, dx, c->a); /* %$x' = a + \lambda^2 + \lambda$% */
dy = MP_NEW;
}
-
+
dy = F_ADD(f, dy, a->x, dx); /* %$ x + x' $% */
dy = F_MUL(f, dy, dy, lambda); /* %$ (x + x') \lambda$% */
dy = F_ADD(f, dy, dy, a->y); /* %$ (x + x') \lambda + y$% */
int rc;
mp *u, *v;
+ if (EC_ATINF(p)) return (0);
v = F_SQR(f, MP_NEW, p->x);
u = F_MUL(f, MP_NEW, v, p->x);
v = F_MUL(f, v, v, c->a);
{
ec t = EC_INIT;
int rc;
-
+
c->ops->fix(c, &t, p);
rc = eccheck(c, &t);
EC_DESTROY(&t);
static void ecdestroy(ec_curve *c)
{
- ecctx *cc = (ecctx *)c;
+ ecctx_bin *cc = (ecctx_bin *)c;
MP_DROP(cc->c.a);
MP_DROP(cc->c.b);
if (cc->bb) MP_DROP(cc->bb);
* Arguments: @field *f@ = the underlying field for this elliptic curve
* @mp *a, *b@ = the coefficients for this curve
*
- * Returns: A pointer to the curve.
+ * Returns: A pointer to the curve, or null.
*
* Use: Creates a curve structure for an elliptic curve defined over
* a binary field. The @binproj@ variant uses projective
ec_curve *ec_bin(field *f, mp *a, mp *b)
{
- ecctx *cc = CREATE(ecctx);
+ ecctx_bin *cc = CREATE(ecctx_bin);
cc->c.ops = &ec_binops;
cc->c.f = f;
cc->c.a = F_IN(f, MP_NEW, a);
ec_curve *ec_binproj(field *f, mp *a, mp *b)
{
- ecctx *cc = CREATE(ecctx);
+ ecctx_bin *cc = CREATE(ecctx_bin);
+ int i;
+ mp *c, *d;
+
cc->c.ops = &ec_binprojops;
cc->c.f = f;
cc->c.a = F_IN(f, MP_NEW, a);
cc->c.b = F_IN(f, MP_NEW, b);
- cc->bb = F_SQRT(f, MP_NEW, b);
- cc->bb = F_SQRT(f, cc->bb, cc->bb);
+
+ c = MP_COPY(cc->c.b);
+ for (i = 0; i < f->nbits - 2; i++)
+ c = F_SQR(f, c, c);
+ d = F_SQR(f, MP_NEW, c); d = F_SQR(f, d, d);
+ if (!MP_EQ(d, cc->c.b)) {
+ MP_DROP(c);
+ MP_DROP(d);
+ MP_DROP(cc->c.a);
+ MP_DROP(cc->c.b);
+ DESTROY(cc);
+ return (0);
+ }
+ cc->bb = c;
+ MP_DROP(d);
return (&cc->c);
}
static const ec_ops ec_binops = {
- ecdestroy, ec_idin, ec_idout, ec_idfix,
+ "bin",
+ ecdestroy, ec_stdsamep, ec_idin, ec_idout, ec_idfix,
ecfind, ecneg, ecadd, ec_stdsub, ecdbl, eccheck
};
static const ec_ops ec_binprojops = {
- ecdestroy, ec_projin, ec_projout, ec_projfix,
+ "binproj",
+ ecdestroy, ec_stdsamep, ec_projin, ec_projout, ec_projfix,
ecfind, ecprojneg, ecprojadd, ec_stdsub, ecprojdbl, ecprojcheck
};
field *f;
ec_curve *c;
ec g = EC_INIT, d = EC_INIT;
- mp *p, *a, *b, *r;
+ mp *p, *a, *b, *r, *beta;
int i, n = argc == 1 ? 1 : atoi(argv[1]);
printf("ec-bin: ");
fflush(stdout);
- a = MP(1);
- b = MP(0x021a5c2c8ee9feb5c4b9a753b7b476b7fd6422ef1f3dd674761fa99d6ac27c8a9a197b272822f6cd57a55aa4f50ae317b13545f);
- p = MP(0x2000000000000000000000000000000000000000000000000000000000000000000000000000000008000000000000000000001);
- r =
- MP(661055968790248598951915308032771039828404682964281219284648798304157774827374805208143723762179110965979867288366567526770);
+ a = MP(0x7ffffffffffffffffffffffffffffffffffffffff);
+ b = MP(0x6645f3cacf1638e139c6cd13ef61734fbc9e3d9fb);
+ p = MP(0x800000000000000000000000000000000000000c9);
+ beta = MP(0x715169c109c612e390d347c748342bcd3b02a0bef);
+ r = MP(0x040000000000000000000292fe77e70c12a4234c32);
- f = field_binpoly(p);
+ f = field_binnorm(p, beta);
c = ec_binproj(f, a, b);
-
- g.x = MP(0x15d4860d088ddb3496b0c6064756260441cde4af1771d4db01ffe5b34e59703dc255a868a1180515603aeab60794e54bb7996a7);
- g.y = MP(0x061b1cfab6be5f32bbfa78324ed106a7636b9c5a7bd198d0158aa4f5488d08f38514f1fdf4b4f40d2181b3681c364ba0273c706);
+ g.x = MP(0x0311103c17167564ace77ccb09c681f886ba54ee8);
+ g.y = MP(0x333ac13c6447f2e67613bf7009daf98c87bb50c7f);
- for (i = 0; i < n; i++) {
+ for (i = 0; i < n; i++) {
ec_mul(c, &d, &g, r);
if (EC_ATINF(&d)) {
fprintf(stderr, "zero too early\n");
ec_destroy(&g);
ec_destroycurve(c);
F_DESTROY(f);
- MP_DROP(p); MP_DROP(a); MP_DROP(b); MP_DROP(r);
+ MP_DROP(p); MP_DROP(a); MP_DROP(b); MP_DROP(r); MP_DROP(beta);
assert(!mparena_count(&mparena_global));
printf("ok\n");
return (0);
projects / u / mdw / catacomb / blobdiff