/* -*-c-*-
*
- * $Id: f-binpoly.c,v 1.5 2004/03/27 17:54:11 mdw Exp $
+ * $Id$
*
* Binary fields with polynomial basis representation
*
* (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: f-binpoly.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 2004/03/23 12:08:26 mdw
- * Random field-element selection.
- *
- * 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 "field.h"
-#include "gf.h"
-#include "gfreduce.h"
+#include "field-guts.h"
#include "mprand.h"
-/*----- Data structures ---------------------------------------------------*/
-
-typedef struct fctx {
- field f;
- gfreduce r;
-} fctx;
-
-/*----- Main code ---------------------------------------------------------*/
+/*----- Polynomial basis --------------------------------------------------*/
/* --- Field operations --- */
-static void fdestroy(field *ff)
-{
- fctx *f = (fctx *)ff;
- gfreduce_destroy(&f->r);
+static void fdestroy(field *ff) {
+ fctx_binpoly *f = (fctx_binpoly *)ff;
+ gfreduce_destroy(&f->r); MP_DROP(f->f.q);
DESTROY(f);
}
-static mp *frand(field *f, mp *d, grand *r)
-{
+static mp *frand(field *f, mp *d, grand *r) {
return (mprand(d, f->nbits, r, 0));
}
-static int fzerop(field *ff, mp *x)
-{
- return (!MP_LEN(x));
-}
+static int fzerop(field *ff, mp *x) { return (MP_ZEROP(x)); }
-static mp *fadd(field *ff, mp *d, mp *x, mp *y)
-{
- return (gf_add(d, x, y));
-}
+static mp *fadd(field *ff, mp *d, mp *x, mp *y) { return (gf_add(d, x, y)); }
-static mp *fmul(field *ff, mp *d, mp *x, mp *y)
-{
- fctx *f = (fctx *)ff;
- d = gf_mul(d, x, y);
+static mp *fmul(field *ff, mp *d, mp *x, mp *y) {
+ fctx_binpoly *f = (fctx_binpoly *)ff; d = gf_mul(d, x, y);
return (gfreduce_do(&f->r, d, d));
}
-static mp *fsqr(field *ff, mp *d, mp *x)
-{
- fctx *f = (fctx *)ff;
- d = gf_sqr(d, x);
+static mp *fsqr(field *ff, mp *d, mp *x) {
+ fctx_binpoly *f = (fctx_binpoly *)ff; d = gf_sqr(d, x);
return (gfreduce_do(&f->r, d, d));
}
-static mp *finv(field *ff, mp *d, mp *x)
-{
- fctx *f = (fctx *)ff;
- gf_gcd(0, 0, &d, f->r.p, x);
+static mp *finv(field *ff, mp *d, mp *x) {
+ fctx_binpoly *f = (fctx_binpoly *)ff;
+ d = gf_modinv(d, x, f->r.p);
return (d);
}
-static mp *freduce(field *ff, mp *d, mp *x)
-{
- fctx *f = (fctx *)ff;
+static mp *freduce(field *ff, mp *d, mp *x) {
+ fctx_binpoly *f = (fctx_binpoly *)ff;
return (gfreduce_do(&f->r, d, x));
}
-static mp *fsqrt(field *ff, mp *d, mp *x)
-{
- fctx *f = (fctx *)ff;
+static mp *fsqrt(field *ff, mp *d, mp *x) {
+ fctx_binpoly *f = (fctx_binpoly *)ff;
return (gfreduce_sqrt(&f->r, d, x));
}
-static mp *fquadsolve(field *ff, mp *d, mp *x)
-{
- fctx *f = (fctx *)ff;
+static mp *fquadsolve(field *ff, mp *d, mp *x) {
+ fctx_binpoly *f = (fctx_binpoly *)ff;
return (gfreduce_quadsolve(&f->r, d, x));
}
/* --- Field operations table --- */
-static field_ops fops = {
+static const field_ops fops = {
FTY_BINARY, "binpoly",
- fdestroy, frand,
+ fdestroy, frand, field_stdsamep,
freduce, field_id,
fzerop, field_id, fadd, fadd, fmul, fsqr, finv, freduce, fsqrt,
fquadsolve,
field *field_binpoly(mp *p)
{
- fctx *f = CREATE(fctx);
+ fctx_binpoly *f = CREATE(fctx_binpoly);
f->f.ops = &fops;
f->f.zero = MP_ZERO;
f->f.one = MP_ONE;
f->f.noctets = (f->f.nbits + 7) >> 3;
gfreduce_create(&f->r, p);
f->f.m = f->r.p;
+ f->f.q = mp_lsl(MP_NEW, MP_ONE, f->f.nbits);
return (&f->f);
}
+/*----- Normal basis ------------------------------------------------------*/
+
+/* --- Field operations --- */
+
+static void fndestroy(field *ff) {
+ fctx_binnorm *f = (fctx_binnorm *)ff; gfreduce_destroy(&f->f.r);
+ gfn_destroy(&f->ntop); gfn_destroy(&f->pton); MP_DROP(f->f.f.q);
+ DESTROY(f);
+}
+
+static int fnsamep(field *ff, field *gg) {
+ fctx_binnorm *f = (fctx_binnorm *)ff, *g = (fctx_binnorm *)gg;
+ return (MP_EQ(f->ntop.r[0], g->ntop.r[0]) && field_stdsamep(ff, gg));
+}
+
+static mp *fnin(field *ff, mp *d, mp *x) {
+ fctx_binnorm *f = (fctx_binnorm *)ff;
+ return (gfn_transform(&f->ntop, d, x));
+}
+
+static mp *fnout(field *ff, mp *d, mp *x) {
+ fctx_binnorm *f = (fctx_binnorm *)ff;
+ return (gfn_transform(&f->pton, d, x));
+}
+
+/* --- Field operations table --- */
+
+static const field_ops fnops = {
+ FTY_BINARY, "binnorm",
+ fndestroy, frand, fnsamep,
+ fnin, fnout,
+ fzerop, field_id, fadd, fadd, fmul, fsqr, finv, freduce, fsqrt,
+ fquadsolve,
+ 0, 0, 0, 0
+};
+
+/* --- @field_binnorm@ --- *
+ *
+ * Arguments: @mp *p@ = the reduction polynomial
+ * @mp *beta@ = representation of normal point
+ *
+ * Returns: A pointer to the field.
+ *
+ * Use: Creates a field structure for a binary field mod @p@ which
+ * uses a normal basis representation externally. Computations
+ * are still done on a polynomial-basis representation.
+ */
+
+field *field_binnorm(mp *p, mp *beta)
+{
+ fctx_binnorm *f = CREATE(fctx_binnorm);
+ f->f.f.ops = &fnops;
+ f->f.f.zero = MP_ZERO;
+ f->f.f.one = MP_ONE;
+ f->f.f.nbits = mp_bits(p) - 1;
+ f->f.f.noctets = (f->f.f.nbits + 7) >> 3;
+ gfreduce_create(&f->f.r, p);
+ f->f.f.m = f->f.r.p;
+ f->f.f.q = mp_lsl(MP_NEW, MP_ONE, f->f.f.nbits);
+ gfn_create(p, beta, &f->ntop, &f->pton);
+ return (&f->f.f);
+}
+
/*----- That's all, folks -------------------------------------------------*/
projects / u / mdw / catacomb / blobdiff