charon-tkm: Implement IANA DH Id to TKM Id mapping

The TKM Diffie-Hellman plugin now maps IANA DH identifiers to TKM DH
algorithm identifiers. The mapping is specified in the daemon's
'dh_mapping' section in the strongswan.conf file:

dh_mapping {
	iana_id1 = tkm_id1
	iana_id2 = tkm_id2
	iana_id3 = tkm_id3
	...
}

Only the mapped IANA IDs are registered as supported DH groups.

src/charon-tkm/tests/diffie_hellman_tests.c

@@ -14,6 +14,7 @@
  * for more details.
  */
 
+#include <daemon.h>
 #include <tests/test_suite.h>
 
 #include "tkm_diffie_hellman.h"

src/charon-tkm/tests/tests.c

@@ -60,15 +60,18 @@ static bool test_runner_init(bool init)
 		static plugin_feature_t features[] = {
 			PLUGIN_REGISTER(NONCE_GEN, tkm_nonceg_create),
 				PLUGIN_PROVIDE(NONCE_GEN),
-			PLUGIN_REGISTER(DH, tkm_diffie_hellman_create),
-				PLUGIN_PROVIDE(DH, MODP_3072_BIT),
-				PLUGIN_PROVIDE(DH, MODP_4096_BIT),
 			PLUGIN_CALLBACK(kernel_ipsec_register, tkm_kernel_ipsec_create),
 				PLUGIN_PROVIDE(CUSTOM, "kernel-ipsec"),
 		};
 		lib->plugins->add_static_features(lib->plugins, "tkm-tests", features,
 										  countof(features), TRUE);
 
+		lib->settings->set_int(lib->settings, "%s.dh_mapping.%d", 1,
+							   charon->name, MODP_3072_BIT);
+		lib->settings->set_int(lib->settings, "%s.dh_mapping.%d", 2,
+							   charon->name, MODP_4096_BIT);
+		register_dh_mapping();
+
 		plugin_loader_add_plugindirs(BUILDDIR "/src/libstrongswan/plugins",
 									 PLUGINS);
 		plugin_loader_add_plugindirs(BUILDDIR "/src/libhydra/plugins",
@@ -90,6 +93,7 @@ static bool test_runner_init(bool init)
 		result = FALSE;
 	}
 
+	destroy_dh_mapping();
 	libcharon_deinit();
 	libhydra_deinit();
 	return result;