Added ecp_write_binary().
diff --git a/library/ecp.c b/library/ecp.c
index 4073288..854da58 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -174,6 +174,43 @@
}
/*
+ * Export a point into unsigned binary data, uncompressed format (SEC1 2.3.3)
+ */
+int ecp_write_binary( const ecp_group *grp, const ecp_point *P,
+ size_t *olen, unsigned char *buf, size_t buflen )
+{
+ int ret;
+ size_t plen;
+
+ /*
+ * Case P == 0
+ */
+ if( mpi_cmp_int( &P->Z, 0 ) == 0 )
+ {
+ if( buflen < 1 )
+ return( POLARSSL_ERR_ECP_GENERIC );
+
+ buf[0] = 0x00;
+ *olen = 1;
+
+ return( 0 );
+ }
+
+ plen = mpi_size( &grp->P );
+ *olen = 2 * plen + 1;
+
+ if( buflen < *olen )
+ return( POLARSSL_ERR_ECP_GENERIC );
+
+ buf[0] = 0x04;
+ MPI_CHK( mpi_write_binary( &P->X, buf + 1, plen ) );
+ MPI_CHK( mpi_write_binary( &P->Y, buf + 1 + plen, plen ) );
+
+cleanup:
+ return( ret );
+}
+
+/*
* Wrapper around fast quasi-modp functions, with fall-back to mpi_mod_mpi.
* See the documentation of struct ecp_group.
*/
