mpi: Add an API for EC math.

* src/context.c, src/context.h: New.
* src/Makefile.am (libgcrypt_la_SOURCES): Add new files.
* src/gcrypt.h.in (struct gcry_context, gcry_ctx_t): New types.
(gcry_ctx_release): New prototype.
(gcry_mpi_ec_p_new, gcry_mpi_ec_get_affine, gcry_mpi_ec_dup)
(gcry_mpi_ec_add, gcry_mpi_ec_mul): New prototypes.
* mpi/ec.c: Include errno.h and context.h.
(_gcry_mpi_ec_init): Rename to ..
(ec_p_init): this, make static, remove allocation and add arg CTX.
(_gcry_mpi_ec_p_internal_new): New; to replace _gcry_mpi_ec_init.
Change all callers to use this func.
(_gcry_mpi_ec_free): Factor code out to ..
(ec_deinit): New func.
(gcry_mpi_ec_p_new): New.
* src/visibility.c: Include context.h and mpi.h.
(gcry_mpi_ec_p_new, gcry_mpi_ec_get_affine, gcry_mpi_ec_dup)
(gcry_mpi_ec_add, gcry_mpi_ec_mul)
(gcry_ctx_release): New wrapper functions.
* src/visibility.h: Mark new wrapper functions visible.
* src/libgcrypt.def, src/libgcrypt.vers: Add new symbols.
* tests/t-mpi-point.c (print_mpi, hex2mpi, cmp_mpihex): New.
(context_alloc): New.
(make_point, basic_ec_math): New.
--

This part finishes the basic API to do EC math.  It provides a wrapper
around all internal functions.  tests/t-mpi-point.c may be useful as
sample code.  Eventually we will add function to retrieve curve
parameters etc.

1 files changed, 44 insertions, 2 deletions

diff --git a/src/visibility.c b/src/visibility.c
index 1fb29f2b..5c3216d2 100644
--- a/src/visibility.c
+++ b/src/visibility.c
@@ -24,8 +24,8 @@
 #define _GCRY_INCLUDED_BY_VISIBILITY_C
 #include "g10lib.h"
 #include "cipher-proto.h"
-
-
+#include "context.h"
+#include "mpi.h"
 
 const char *
 gcry_strerror (gcry_error_t err)
@@ -461,6 +461,42 @@ gcry_mpi_point_snatch_set (gcry_mpi_point_t point,
   return _gcry_mpi_point_snatch_set (point, x, y, z);
 }
 
+gcry_ctx_t
+gcry_mpi_ec_p_new (gcry_mpi_t p, gcry_mpi_t a)
+{
+  return _gcry_mpi_ec_p_new (p, a);
+}
+
+int
+gcry_mpi_ec_get_affine (gcry_mpi_t x, gcry_mpi_t y, gcry_mpi_point_t point,
+                        gcry_ctx_t ctx)
+{
+  return _gcry_mpi_ec_get_affine (x, y, point,
+                                  _gcry_ctx_get_pointer (ctx, CONTEXT_TYPE_EC));
+}
+
+void
+gcry_mpi_ec_dup (gcry_mpi_point_t w, gcry_mpi_point_t u, gcry_ctx_t ctx)
+{
+  _gcry_mpi_ec_dup_point (w, u, _gcry_ctx_get_pointer (ctx, CONTEXT_TYPE_EC));
+}
+
+void
+gcry_mpi_ec_add (gcry_mpi_point_t w,
+                 gcry_mpi_point_t u, gcry_mpi_point_t v, gcry_ctx_t ctx)
+{
+  _gcry_mpi_ec_add_points (w, u, v,
+                           _gcry_ctx_get_pointer (ctx, CONTEXT_TYPE_EC));
+}
+
+void
+gcry_mpi_ec_mul (gcry_mpi_point_t w, gcry_mpi_t n, gcry_mpi_point_t u,
+                 gcry_ctx_t ctx)
+{
+  _gcry_mpi_ec_mul_point (w, n, u,
+                          _gcry_ctx_get_pointer (ctx, CONTEXT_TYPE_EC));
+}
+
 unsigned int
 gcry_mpi_get_nbits (gcry_mpi_t a)
 {
@@ -1067,6 +1103,12 @@ gcry_prime_check (gcry_mpi_t x, unsigned int flags)
 }
 
 void
+gcry_ctx_release (gcry_ctx_t ctx)
+{
+  _gcry_ctx_release (ctx);
+}
+
+void
 gcry_set_progress_handler (gcry_handler_progress_t cb, void *cb_data)
 {
   _gcry_set_progress_handler (cb, cb_data);