Random field-element selection.

[u/mdw/catacomb] / f-binpoly.c

diff --git a/f-binpoly.c b/f-binpoly.c
index 02e683d..463dbb2 100644 (file)
--- a/f-binpoly.c
+++ b/f-binpoly.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: f-binpoly.c,v 1.2 2004/03/21 22:52:06 mdw Exp $
+ * $Id: f-binpoly.c,v 1.3 2004/03/23 12:08:26 mdw Exp $
  *
  * Binary fields with polynomial basis representation
  *
@@ -30,6 +30,9 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: f-binpoly.c,v $
+ * 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.
  *
@@ -45,6 +48,7 @@
 #include "field.h"
 #include "gf.h"
 #include "gfreduce.h"
+#include "mprand.h"
 
 /*----- Data structures ---------------------------------------------------*/
 
@@ -64,6 +68,12 @@ static void fdestroy(field *ff)
   DESTROY(f);
 }
 
+static mp *frand(field *ff, grand *r, mp *d)
+{
+  fctx *f = (fctx *)ff;
+  return (mprand(d, mp_octets(f->r.p) - 1, r, 0));
+}
+
 static int fzerop(field *ff, mp *x)
 {
   return (!MP_LEN(x));
@@ -116,7 +126,7 @@ static mp *fquadsolve(field *ff, mp *d, mp *x)
 /* --- Field operations table --- */
 
 static field_ops fops = {
-  fdestroy,
+  fdestroy, frand,
   freduce, field_id,
   fzerop, field_id, fadd, fadd, fmul, fsqr, finv, freduce, fsqrt,
   fquadsolve,