X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/f46efa79cd2bb9adc81541f1218965f85a6b2eef..432c4e184d44704511a5991b80224a87cb1d4613:/ec.h

diff --git a/ec.h b/ec.h
index d398f4a..79e3654 100644
--- a/ec.h
+++ b/ec.h
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: ec.h,v 1.7 2004/03/23 15:19:32 mdw Exp $
+ * $Id: ec.h,v 1.8 2004/03/27 17:54:11 mdw Exp $
  *
  * Elliptic curve definitions
  *
@@ -30,6 +30,9 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: ec.h,v $
+ * Revision 1.8  2004/03/27 17:54:11  mdw
+ * Standard curves and curve checking.
+ *
  * Revision 1.7  2004/03/23 15:19:32  mdw
  * Test elliptic curves more thoroughly.
  *
@@ -74,8 +77,17 @@
 
 /*----- Header files ------------------------------------------------------*/
 
-#include "field.h"
-#include "mp.h"
+#ifndef CATACOMB_FIELD_H
+#  include "field.h"
+#endif
+
+#ifndef CATACOMB_MP_H
+#  include "mp.h"
+#endif
+
+#ifndef CATACOMB_QDPARSE_H
+#  include "qdparse.h"
+#endif
 
 /*----- Data structures ---------------------------------------------------*/
 
@@ -84,6 +96,7 @@
 typedef struct ec_curve {
   const struct ec_ops *ops;		/* Curve operations */
   field *f;				/* Underlying field structure */
+  mp *a, *b;				/* Standard params (internal form) */
 } ec_curve;
 
 /* --- An elliptic curve point --- */
@@ -135,6 +148,15 @@ typedef struct ec_ops {
 #define EC_DBL(c, d, p)		(c)->ops->dbl((c), (d), (p))
 #define EC_CHECK(c, p)		(c)->ops->check((c), (p))
 
+/* --- Elliptic curve parameters --- */
+
+typedef struct ec_info {
+  ec_curve *c;				/* The actual curve */
+  ec g;					/* The common point */
+  mp *r;				/* Order of %$g$% */
+  mp *h;				/* Cofactor %$h = \#E/r$% */
+} ec_info;
+
 /*----- Simple memory management things -----------------------------------*/
 
 /* --- @ec_create@ --- *
@@ -480,6 +502,100 @@ extern ec_curve *ec_primeproj(field */*f*/, mp */*a*/, mp */*b*/);
 extern ec_curve *ec_bin(field */*f*/, mp */*a*/, mp */*b*/);
 extern ec_curve *ec_binproj(field */*f*/, mp */*a*/, mp */*b*/);
 
+/*----- Curve parameter sets ----------------------------------------------*/
+
+/* --- @ec_curveparse@ --- *
+ *
+ * Arguments:	@qd_parse *qd@ = parser context
+ *
+ * Returns:	Elliptic curve pointer if OK, or null.
+ *
+ * Use:		Parses an elliptic curve description, which has the form
+ *
+ *		  * a field description
+ *		  * an optional `/'
+ *		  * `prime', `primeproj', `bin', or `binproj'
+ *		  * an optional `:'
+ *		  * the %$a$% parameter
+ *		  * an optional `,'
+ *		  * the %$b$% parameter
+ */
+
+extern ec_curve *ec_curveparse(qd_parse */*qd*/);
+
+/* --- @ec_ptparse@ --- *
+ *
+ * Arguments:	@qd_parse *qd@ = parser context
+ *		@ec *p@ = where to put the point
+ *
+ * Returns:	The point address, or null.
+ *
+ * Use:		Parses an elliptic curve point.  This has the form
+ *
+ *		  * %$x$%-coordinate
+ *		  * optional `,'
+ *		  * %$y$%-coordinate
+ */
+
+extern ec *ec_ptparse(qd_parse */*qd*/, ec */*p*/);
+
+/* --- @ec_infoparse@ --- *
+ *
+ * Arguments:	@qd_parse *qd@ = parser context
+ *		@ec_info *ei@ = curve information block, currently
+ *			uninitialized
+ *
+ * Returns:	Zero on success, nonzero on failure.
+ *
+ * Use:		Parses an elliptic curve information string, and stores the
+ *		information in @ei@.  This has the form
+ *
+ *		  * elliptic curve description
+ *		  * optional `/'
+ *		  * common point
+ *		  * optional `:'
+ *		  * group order
+ *		  * optional `*'
+ *		  * cofactor
+ */
+
+extern int ec_infoparse(qd_parse */*qd*/, ec_info */*ei*/);
+
+/* --- @ec_getinfo@ --- *
+ *
+ * Arguments:	@ec_info *ei@ = where to write the information
+ *		@const char *p@ = string describing a curve
+ *
+ * Returns:	Null on success, or a pointer to an error message.
+ *
+ * Use:		Parses out information about a curve.  The string is either a
+ *		standard curve name, or a curve info string.
+ */
+
+extern const char *ec_getinfo(ec_info */*ei*/, const char */*p*/);
+
+/* --- @ec_freeinfo@ --- *
+ *
+ * Arguments:	@ec_info *ei@ = elliptic curve information block to free
+ *
+ * Returns:	---
+ *
+ * Use:		Frees the information block.
+ */
+
+extern void ec_freeinfo(ec_info */*ei*/);
+
+/* --- @ec_checkinfo@ --- *
+ *
+ * Arguments:	@const ec_info *ei@ = elliptic curve information block
+ *
+ * Returns:	Null if OK, or pointer to error message.
+ *
+ * Use:		Checks an elliptic curve according to the rules in SEC1.
+ */
+
+extern const char *ec_checkinfo(const ec_info */*ei*/, grand */*gr*/);
+
 /*----- That's all, folks -------------------------------------------------*/
 
 #ifdef __cplusplus