p-cscf: Make sending requests configurable and disable it by default

conf/Makefile.am

@@ -73,6 +73,7 @@ plugins = \
 	plugins/ntru.opt \
 	plugins/openssl.opt \
 	plugins/osx-attr.opt \
+	plugins/p-cscf.opt \
 	plugins/pkcs11.opt \
 	plugins/radattr.opt \
 	plugins/random.opt \

conf/plugins/p-cscf.opt

@@ -0,0 +1,11 @@
+charon.plugins.p-cscf.enable {}
+	Section to enable requesting P-CSCF server addresses for individual
+	connections.
+
+charon.plugins.p-cscf.enable.<conn> = no
+	<conn> is the name of a connection with an ePDG from which to request
+	P-CSCF server addresses.
+
+	<conn> is the name of a connection with an ePDG from which to request
+	P-CSCF server addresses.  Requests will be sent for addresses of the same
+	families for which internal IPs are requested.

src/libcharon/plugins/p_cscf/p_cscf_handler.c

@@ -135,9 +135,13 @@ METHOD(attribute_handler_t, create_attribute_enumerator, enumerator_t *,
 			.enumerate = (void*)_enumerate_attrs,
 			.destroy = (void*)free,
 		},
-		.request_ipv4 = has_host_family(vips, AF_INET),
-		.request_ipv6 = has_host_family(vips, AF_INET6),
 	);
+	if (lib->settings->get_bool(lib->settings, "%s.plugins.p-cscf.enable.%s",
+								FALSE, lib->ns, ike_sa->get_name(ike_sa)))
+	{
+		enumerator->request_ipv4 = has_host_family(vips, AF_INET);
+		enumerator->request_ipv6 = has_host_family(vips, AF_INET6);
+	}
 	return &enumerator->public;
 }