/* -*-c-*-
*
- * $Id: ec.h,v 1.1 2001/04/29 18:12:33 mdw Exp $
+ * $Id: ec.h,v 1.2 2001/05/07 17:29:44 mdw Exp $
*
* Elliptic curve definitions
*
/*----- Revision history --------------------------------------------------*
*
* $Log: ec.h,v $
+ * 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.
*
typedef struct ec_ops {
void (*destroy)(ec_curve */*c*/);
- int (*find)(ec_curve */*c*/, ec */*d*/, mp */*x*/);
- void (*add)(ec_curve */*c*/, ec */*d*/, ec */*p*/, ec */*q*/);
- void (*dbl)(ec_curve */*c*/, ec */*d*/, ec */*p*/);
+ ec *(*in)(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
+ ec *(*out)(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
+ ec *(*find)(ec_curve */*c*/, ec */*d*/, mp */*x*/);
+ ec *(*add)(ec_curve */*c*/, ec */*d*/, const ec */*p*/, const ec */*q*/);
+ ec *(*dbl)(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
} ec_ops;
#define EC_DESTROY(c) (c)->ops->destroy((c))
+#define EC_IN(c, d, p) (c)->ops->in((c), (d), (p))
+#define EC_OUT(c, d, p) (c)->ops->in((c), (d), (p))
+
#define EC_FIND(c, d, x) (c)->ops->find((c), (d), (x))
#define EC_ADD(c, d, p, q) (c)->ops->add((c), (d), (p), (q))
#define EC_DBL(c, d, p) (c)->ops->dbl((c), (d), (p))
*
* Arguments: @ec *p@ = pointer to an elliptic-curve point
*
- * Returns: ---
+ * Returns: The argument @p@.
*
* Use: Initializes a new point. The initial value is the additive
* identity (which is universal for all curves).
_p->x = _p->y = _p->z = MP_NEW; \
} while (0)
-extern void ec_create(ec */*p*/);
+extern ec *ec_create(ec */*p*/);
/* --- @ec_destroy@ --- *
*
*
* Arguments: @ec *p@ = pointer to a point
*
- * Returns: ---
+ * Returns: The argument @p@.
*
* Use: Sets the given point to be the point %$O$% at infinity.
*/
} \
} while (0)
-extern void ec_setinf(ec */*p*/);
+extern ec *ec_setinf(ec */*p*/);
/* --- @ec_copy@ --- *
*
* Arguments: @ec *d@ = pointer to destination point
* @const ec *p@ = pointer to source point
*
- * Returns: ---
+ * Returns: The destination @d@.
*
* Use: Creates a copy of an elliptic curve point.
*/
} \
} while (0)
-extern void ec_copy(ec */*d*/, const ec */*p*/);
+extern ec *ec_copy(ec */*d*/, const ec */*p*/);
/*----- Interesting arithmetic --------------------------------------------*/
* @ec *d@ = pointer to the destination point
* @const ec *p, *q@ = pointers to the operand points
*
- * Returns: ---
+ * Returns: The destination @d@.
*
* Use: Adds two points on an elliptic curve.
*/
-extern void ec_add(ec_curve */*c*/, ec */*d*/,
- const ec */*p*/, const ec */*q*/);
+extern ec *ec_add(ec_curve */*c*/, ec */*d*/,
+ const ec */*p*/, const ec */*q*/);
/* --- @ec_dbl@ --- *
*
* @ec *d@ = pointer to the destination point
* @const ec *p@ = pointer to the operand point
*
- * Returns: ---
+ * Returns: The destination @d@.
*
* Use: Doubles a point on an elliptic curve.
*/
-extern void ec_dbl(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
+extern ec *ec_dbl(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
/* --- @ec_mul@ --- *
*
* @const ec *p@ = pointer to the generator point
* @mp *n@ = integer multiplier
*
- * Returns: ---
+ * Returns: The destination @d@.
*
* Use: Multiplies a point by a scalar, returning %$n p$%.
*/
-extern void ec_mul(ec_curve */*c*/, ec */*d*/, const ec */*p*/, mp */*n*/);
+extern ec *ec_mul(ec_curve */*c*/, ec */*d*/, const ec */*p*/, mp */*n*/);
+
+/*----- Standard curve operations -----------------------------------------*/
+
+/* --- @ec_idin@, @ec_idout@ --- *
+ *
+ * Arguments: @ec_curve *c@ = pointer to an elliptic curve
+ * @ec *d@ = pointer to the destination
+ * @const ec *p@ = pointer to a source point
+ *
+ * Returns: The destination @d@.
+ *
+ * Use: An identity operation if your curve has no internal
+ * representation. (The field internal representation is still
+ * used.)
+ */
+
+extern ec *ec_idin(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
+extern ec *ec_idout(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
+
+/* --- @ec_projin@, @ec_projout@ --- *
+ *
+ * Arguments: @ec_curve *c@ = pointer to an elliptic curve
+ * @ec *d@ = pointer to the destination
+ * @const ec *p@ = pointer to a source point
+ *
+ * Returns: The destination @d@.
+ *
+ * Use: Conversion functions if your curve operations use a
+ * projective representation.
+ */
+
+extern ec *ec_projin(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
+extern ec *ec_projout(ec_curve */*c*/, ec */*d*/, const ec */*p*/);
/*----- Creating curves ---------------------------------------------------*/