X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/432c4e184d44704511a5991b80224a87cb1d4613..b817bfc642225b8c3c0b6a7e42d1fb949b61a606:/ec.c

diff --git a/ec.c b/ec.c
index d4dfafb..a84dd7a 100644
--- a/ec.c
+++ b/ec.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: ec.c,v 1.7 2004/03/27 17:54:11 mdw Exp $
+ * $Id: ec.c,v 1.10 2004/04/08 01:36:15 mdw Exp $
  *
  * Elliptic curve definitions
  *
@@ -27,46 +27,28 @@
  * MA 02111-1307, USA.
  */
 
-/*----- Revision history --------------------------------------------------* 
- *
- * $Log: ec.c,v $
- * Revision 1.7  2004/03/27 17:54:11  mdw
- * Standard curves and curve checking.
- *
- * Revision 1.6  2004/03/23 15:19:32  mdw
- * Test elliptic curves more thoroughly.
- *
- * Revision 1.5  2004/03/21 22:52:06  mdw
- * Merge and close elliptic curve branch.
- *
- * Revision 1.4.4.2  2004/03/20 00:13:31  mdw
- * Projective coordinates for prime curves
- *
- * Revision 1.4.4.1  2003/06/10 13:43:53  mdw
- * Simple (non-projective) curves over prime fields now seem to work.
- *
- * Revision 1.4  2003/05/15 23:25:59  mdw
- * Make elliptic curve stuff build.
- *
- * Revision 1.3  2002/01/13 13:48:44  mdw
- * Further progress.
- *
- * Revision 1.2  2001/05/07 17:29:44  mdw
- * Treat projective coordinates as an internal representation.  Various
- * minor interface changes.
- *
- * Revision 1.1  2001/04/29 18:12:33  mdw
- * Prototype version.
- *
- */
-
 /*----- Header files ------------------------------------------------------*/
 
 #include "ec.h"
-#include "ec-exp.h"
 
 /*----- Trivial wrappers --------------------------------------------------*/
 
+/* --- @ec_samep@ --- *
+ *
+ * Arguments:	@ec_curve *c, *d@ = two elliptic curves
+ *
+ * Returns:	Nonzero if the curves are identical (not just isomorphic).
+ *
+ * Use:		Checks for sameness of curves.  This function does the full
+ *		check, not just the curve-type-specific check done by the
+ *		@sampep@ field operation.
+ */
+
+int ec_samep(ec_curve *c, ec_curve *d)
+{
+  return (field_samep(c->f, d->f) && c->ops == d->ops && EC_SAMEP(c, d));
+}
+
 /* --- @ec_create@ --- *
  *
  * Arguments:	@ec *p@ = pointer to an elliptic-curve point
@@ -135,6 +117,20 @@ int ec_eq(const ec *p, const ec *q) { return (EC_EQ(p, q)); }
 
 /*----- Standard curve operations -----------------------------------------*/
 
+/* --- @ec_stdsamep@ --- *
+ *
+ * Arguments:	@ec_curve *c, *d@ = two elliptic curves
+ *
+ * Returns:	Nonzero if the curves are identical (not just isomorphic).
+ *
+ * Use:		Simple sameness check on @a@ and @b@ curve members.
+ */
+
+int ec_stdsamep(ec_curve *c, ec_curve *d)
+{
+  return (MP_EQ(c->a, d->a) && MP_EQ(c->b, d->b));
+}
+
 /* --- @ec_idin@, @ec_idout@, @ec_idfix@ --- *
  *
  * Arguments:	@ec_curve *c@ = pointer to an elliptic curve
@@ -180,7 +176,7 @@ ec *ec_idfix(ec_curve *c, ec *d, const ec *p)
   return (d);
 }
 
-/* --- @ec_projin@, @ec_projout@ --- *
+/* --- @ec_projin@, @ec_projout@, @ec_projfix@ --- *
  *
  * Arguments:	@ec_curve *c@ = pointer to an elliptic curve
  *		@ec *d@ = pointer to the destination
@@ -246,7 +242,7 @@ ec *ec_projfix(ec_curve *c, ec *d, const ec *p)
     mp_drop(d->z);
     d->z = MP_COPY(f->one);
   }
-  return (d);  
+  return (d);
 }
 
 /* --- @ec_stdsub@ --- *
@@ -432,48 +428,4 @@ ec *ec_rand(ec_curve *c, ec *d, grand *r)
   return (EC_OUT(c, d, d));    
 }
 
-/* --- @ec_imul@, @ec_mul@ --- *
- *
- * Arguments:	@ec_curve *c@ = pointer to an elliptic curve
- *		@ec *d@ = pointer to the destination point
- *		@const ec *p@ = pointer to the generator point
- *		@mp *n@ = integer multiplier
- *
- * Returns:	The destination @d@.
- *
- * Use:		Multiplies a point by a scalar, returning %$n p$%.  The
- *		@imul@ variant uses internal representations for argument
- *		and result.
- */
-
-ec *ec_imul(ec_curve *c, ec *d, const ec *p, mp *n)
-{
-  ec t = EC_INIT;
-
-  EC_COPY(&t, p);
-  if (t.x && (n->f & MP_BURN))
-    t.x->f |= MP_BURN;
-  MP_SHRINK(n);
-  EC_SETINF(d);
-  if (MP_LEN(n) == 0)
-    ;
-  else {
-    if (n->f & MP_NEG)
-      EC_NEG(c, &t, &t);
-    if (MP_LEN(n) < EXP_THRESH)
-      EXP_SIMPLE(*d, t, n);
-    else
-      EXP_WINDOW(*d, t, n);
-  }
-  EC_DESTROY(&t);
-  return (d);
-}
-
-ec *ec_mul(ec_curve *c, ec *d, const ec *p, mp *n)
-{
-  EC_IN(c, d, p);
-  ec_imul(c, d, d, n);
-  return (EC_OUT(c, d, d));
-}
-
 /*----- That's all, folks -------------------------------------------------*/