--- /dev/null
+/*************************************************
+* Exim - an Internet mail transport agent *
+*************************************************/
+
+/* Copyright (c) Jeremy Harris 2016 */
+/* See the file NOTICE for conditions of use and distribution. */
+
+/* RSA and SHA routine selection for PDKIM */
+
+#include "../exim.h"
+#include "../sha_ver.h"
+
+
+#ifdef USE_GNUTLS
+# include <gnutls/gnutls.h>
+
+# if GNUTLS_VERSION_NUMBER >= 0x30000
+# define RSA_GNUTLS
+# else
+# define RSA_GCRYPT
+# endif
+
+#else
+# define RSA_OPENSSL
+#endif
+