Merge branch 'p-cscf'

This adds the p-cscf plugin that can request P-CSCF server addresses from
an ePDG via IKEv2 (RFC 7651).  Addresses of the same families as requested
virtual IPs are requested if enabled in strongswan.conf for a particular
connection.  The plugin currently writes received addresses to the log.

11 files changed, 458 insertions, 24 deletions

diff --git a/src/libcharon/Android.mk b/src/libcharon/Android.mk
index 8f8c96588..55e6bc58b 100644
--- a/src/libcharon/Android.mk
+++ b/src/libcharon/Android.mk
@@ -156,6 +156,8 @@ endif
 
 LOCAL_SRC_FILES += $(call add_plugin, attr)
 
+LOCAL_SRC_FILES += $(call add_plugin, p-cscf)
+
 LOCAL_SRC_FILES += $(call add_plugin, eap-aka)
 
 LOCAL_SRC_FILES += $(call add_plugin, eap-aka-3gpp2)
diff --git a/src/libcharon/Makefile.am b/src/libcharon/Makefile.am
index 61e57c1cb..9f0707813 100644
--- a/src/libcharon/Makefile.am
+++ b/src/libcharon/Makefile.am
@@ -489,6 +489,13 @@ if MONOLITHIC
 endif
 endif
 
+if USE_P_CSCF
+  SUBDIRS += plugins/p_cscf
+if MONOLITHIC
+  libcharon_la_LIBADD += plugins/p_cscf/libstrongswan-p-cscf.la
+endif
+endif
+
 if USE_ANDROID_DNS
   SUBDIRS += plugins/android_dns
 if MONOLITHIC
diff --git a/src/libcharon/attributes/attributes.c b/src/libcharon/attributes/attributes.c
index 9fabcf4e4..0f28d55fa 100644
--- a/src/libcharon/attributes/attributes.c
+++ b/src/libcharon/attributes/attributes.c
@@ -17,7 +17,7 @@
 
 #include "attributes.h"
 
-ENUM_BEGIN(configuration_attribute_type_names, INTERNAL_IP4_ADDRESS, HOME_AGENT_ADDRESS,
+ENUM_BEGIN(configuration_attribute_type_names, INTERNAL_IP4_ADDRESS, P_CSCF_IP6_ADDRESS,
 	"INTERNAL_IP4_ADDRESS",
 	"INTERNAL_IP4_NETMASK",
 	"INTERNAL_IP4_DNS",
@@ -36,8 +36,10 @@ ENUM_BEGIN(configuration_attribute_type_names, INTERNAL_IP4_ADDRESS, HOME_AGENT_
 	"MIP6_HOME_PREFIX",
 	"INTERNAL_IP6_LINK",
 	"INTERNAL_IP6_PREFIX",
-	"HOME_AGENT_ADDRESS");
-ENUM_NEXT(configuration_attribute_type_names, XAUTH_TYPE, XAUTH_ANSWER, HOME_AGENT_ADDRESS,
+	"HOME_AGENT_ADDRESS",
+	"P_CSCF_IP4_ADDRESS",
+	"P_CSCF_IP6_ADDRESS");
+ENUM_NEXT(configuration_attribute_type_names, XAUTH_TYPE, XAUTH_ANSWER, P_CSCF_IP6_ADDRESS,
 	"XAUTH_TYPE",
 	"XAUTH_USER_NAME",
 	"XAUTH_USER_PASSWORD",
@@ -65,7 +67,7 @@ ENUM_NEXT(configuration_attribute_type_names, UNITY_BANNER, UNITY_DDNS_HOSTNAME,
 	"UNITY_DDNS_HOSTNAME");
 ENUM_END(configuration_attribute_type_names, UNITY_DDNS_HOSTNAME);
 
-ENUM_BEGIN(configuration_attribute_type_short_names, INTERNAL_IP4_ADDRESS, HOME_AGENT_ADDRESS,
+ENUM_BEGIN(configuration_attribute_type_short_names, INTERNAL_IP4_ADDRESS, P_CSCF_IP6_ADDRESS,
 	"ADDR",
 	"MASK",
 	"DNS",
@@ -84,8 +86,10 @@ ENUM_BEGIN(configuration_attribute_type_short_names, INTERNAL_IP4_ADDRESS, HOME_
 	"MIP6HPFX",
 	"LINK6",
 	"PFX6",
-	"HOA");
-ENUM_NEXT(configuration_attribute_type_short_names, XAUTH_TYPE, XAUTH_ANSWER, HOME_AGENT_ADDRESS,
+	"HOA",
+	"PCSCF4",
+	"PCSCF6");
+ENUM_NEXT(configuration_attribute_type_short_names, XAUTH_TYPE, XAUTH_ANSWER, P_CSCF_IP6_ADDRESS,
 	"X_TYPE",
 	"X_USER",
 	"X_PWD",
diff --git a/src/libcharon/attributes/attributes.h b/src/libcharon/attributes/attributes.h
index 5d1e9f9ba..dd1db4fc3 100644
--- a/src/libcharon/attributes/attributes.h
+++ b/src/libcharon/attributes/attributes.h
@@ -49,6 +49,9 @@ enum configuration_attribute_type_t {
 	INTERNAL_IP6_LINK       = 17,
 	INTERNAL_IP6_PREFIX     = 18,
 	HOME_AGENT_ADDRESS		= 19,
+	/* RFC 7651 */
+	P_CSCF_IP4_ADDRESS		= 20,
+	P_CSCF_IP6_ADDRESS		= 21,
 	/* XAUTH attributes */
 	XAUTH_TYPE              = 16520,
 	XAUTH_USER_NAME         = 16521,
diff --git a/src/libcharon/encoding/payloads/configuration_attribute.c b/src/libcharon/encoding/payloads/configuration_attribute.c
index 0bc94708f..4ecdf569d 100644
--- a/src/libcharon/encoding/payloads/configuration_attribute.c
+++ b/src/libcharon/encoding/payloads/configuration_attribute.c
@@ -132,6 +132,7 @@ METHOD(payload_t, verify, status_t,
 		case INTERNAL_IP4_NBNS:
 		case INTERNAL_ADDRESS_EXPIRY:
 		case INTERNAL_IP4_DHCP:
+		case P_CSCF_IP4_ADDRESS:
 			if (this->length_or_value != 0 && this->length_or_value != 4)
 			{
 				failed = TRUE;
@@ -160,6 +161,7 @@ METHOD(payload_t, verify, status_t,
 		case INTERNAL_IP6_DNS:
 		case INTERNAL_IP6_NBNS:
 		case INTERNAL_IP6_DHCP:
+		case P_CSCF_IP6_ADDRESS:
 			if (this->length_or_value != 0 && this->length_or_value != 16)
 			{
 				failed = TRUE;
diff --git a/src/libcharon/plugins/attr/attr_provider.c b/src/libcharon/plugins/attr/attr_provider.c
index cac0ae4bf..1de571c3f 100644
--- a/src/libcharon/plugins/attr/attr_provider.c
+++ b/src/libcharon/plugins/attr/attr_provider.c
@@ -54,6 +54,8 @@ struct attribute_entry_t {
 	configuration_attribute_type_t type;
 	/** attribute value */
 	chunk_t value;
+	/** associated IKE version */
+	ike_version_t ike;
 };
 
 /**
@@ -66,26 +68,51 @@ static void attribute_destroy(attribute_entry_t *this)
 }
 
 /**
+ * Data for attribute enumerator
+ */
+typedef struct {
+	rwlock_t *lock;
+	ike_version_t ike;
+} enumerator_data_t;
+
+/**
  * convert enumerator value from attribute_entry
  */
-static bool attr_enum_filter(void *null, attribute_entry_t **in,
+static bool attr_enum_filter(enumerator_data_t *data, attribute_entry_t **in,
 			configuration_attribute_type_t *type, void* none, chunk_t *value)
 {
-	*type = (*in)->type;
-	*value = (*in)->value;
-	return TRUE;
+	if ((*in)->ike == IKE_ANY || (*in)->ike == data->ike)
+	{
+		*type = (*in)->type;
+		*value = (*in)->value;
+		return TRUE;
+	}
+	return FALSE;
+}
+
+CALLBACK(attr_enum_destroy, void,
+	enumerator_data_t *data)
+{
+	data->lock->unlock(data->lock);
+	free(data);
 }
 
 METHOD(attribute_provider_t, create_attribute_enumerator, enumerator_t*,
 	private_attr_provider_t *this, linked_list_t *pools,
 	ike_sa_t *ike_sa, linked_list_t *vips)
 {
+	enumerator_data_t *data;
+
 	if (vips->get_count(vips))
 	{
+		INIT(data,
+			.lock = this->lock,
+			.ike = ike_sa->get_version(ike_sa),
+		);
 		this->lock->read_lock(this->lock);
 		return enumerator_create_filter(
 				this->attributes->create_enumerator(this->attributes),
-				(void*)attr_enum_filter, this->lock, (void*)this->lock->unlock);
+				(void*)attr_enum_filter, data, attr_enum_destroy);
 	}
 	return enumerator_create_empty();
 }
@@ -116,8 +143,6 @@ static void add_legacy_entry(private_attr_provider_t *this, char *key, int nr,
 		host = host_create_from_string(str, 0);
 		if (host)
 		{
-			entry = malloc_thing(attribute_entry_t);
-
 			if (host->get_family(host) == AF_INET6)
 			{
 				switch (type)
@@ -132,8 +157,11 @@ static void add_legacy_entry(private_attr_provider_t *this, char *key, int nr,
 						break;
 				}
 			}
-			entry->type = type;
-			entry->value = chunk_clone(host->get_address(host));
+			INIT(entry,
+				.type = type,
+				.value = chunk_clone(host->get_address(host)),
+				.ike = IKE_ANY,
+			);
 			host->destroy(host);
 			DBG2(DBG_CFG, "loaded legacy entry attribute %N: %#B",
 				 configuration_attribute_type_names, entry->type, &entry->value);
@@ -149,18 +177,20 @@ typedef struct {
 	char *name;
 	configuration_attribute_type_t v4;
 	configuration_attribute_type_t v6;
+	ike_version_t ike;
 } attribute_type_key_t;
 
 static attribute_type_key_t keys[] = {
-	{"address",			INTERNAL_IP4_ADDRESS,	INTERNAL_IP6_ADDRESS},
-	{"dns",				INTERNAL_IP4_DNS,		INTERNAL_IP6_DNS},
-	{"nbns",			INTERNAL_IP4_NBNS,		INTERNAL_IP6_NBNS},
-	{"dhcp",			INTERNAL_IP4_DHCP,		INTERNAL_IP6_DHCP},
-	{"netmask",			INTERNAL_IP4_NETMASK,	INTERNAL_IP6_NETMASK},
-	{"server",			INTERNAL_IP4_SERVER,	INTERNAL_IP6_SERVER},
-	{"subnet",			INTERNAL_IP4_SUBNET,	INTERNAL_IP6_SUBNET},
-	{"split-include",	UNITY_SPLIT_INCLUDE,	UNITY_SPLIT_INCLUDE},
-	{"split-exclude",	UNITY_LOCAL_LAN,		UNITY_LOCAL_LAN},
+	{"address",			INTERNAL_IP4_ADDRESS,	INTERNAL_IP6_ADDRESS,	IKE_ANY},
+	{"dns",				INTERNAL_IP4_DNS,		INTERNAL_IP6_DNS,		IKE_ANY},
+	{"nbns",			INTERNAL_IP4_NBNS,		INTERNAL_IP6_NBNS,		IKE_ANY},
+	{"dhcp",			INTERNAL_IP4_DHCP,		INTERNAL_IP6_DHCP,		IKE_ANY},
+	{"netmask",			INTERNAL_IP4_NETMASK,	INTERNAL_IP6_NETMASK,	IKE_ANY},
+	{"server",			INTERNAL_IP4_SERVER,	INTERNAL_IP6_SERVER,	IKE_ANY},
+	{"subnet",			INTERNAL_IP4_SUBNET,	INTERNAL_IP6_SUBNET,	IKE_ANY},
+	{"p-cscf",			P_CSCF_IP4_ADDRESS,		P_CSCF_IP6_ADDRESS,		IKEV2},
+	{"split-include",	UNITY_SPLIT_INCLUDE,	UNITY_SPLIT_INCLUDE,	IKEV1},
+	{"split-exclude",	UNITY_LOCAL_LAN,		UNITY_LOCAL_LAN,		IKEV1},
 };
 
 /**
@@ -275,6 +305,7 @@ static void load_entries(private_attr_provider_t *this)
 			INIT(entry,
 				.type = type,
 				.value = data,
+				.ike = mapped ? mapped->ike : IKE_ANY,
 			);
 			DBG2(DBG_CFG, "loaded attribute %N: %#B",
 				 configuration_attribute_type_names, entry->type, &entry->value);
diff --git a/src/libcharon/plugins/p_cscf/Makefile.am b/src/libcharon/plugins/p_cscf/Makefile.am
new file mode 100644
index 000000000..1e00a56a8
--- /dev/null
+++ b/src/libcharon/plugins/p_cscf/Makefile.am
@@ -0,0 +1,19 @@
+AM_CPPFLAGS = \
+	-I$(top_srcdir)/src/libstrongswan \
+	-I$(top_srcdir)/src/libhydra \
+	-I$(top_srcdir)/src/libcharon
+
+AM_CFLAGS = \
+	$(PLUGIN_CFLAGS)
+
+if MONOLITHIC
+noinst_LTLIBRARIES = libstrongswan-p-cscf.la
+else
+plugin_LTLIBRARIES = libstrongswan-p-cscf.la
+endif
+
+libstrongswan_p_cscf_la_SOURCES = \
+	p_cscf_plugin.c p_cscf_plugin.h \
+	p_cscf_handler.c p_cscf_handler.h
+
+libstrongswan_p_cscf_la_LDFLAGS = -module -avoid-version
diff --git a/src/libcharon/plugins/p_cscf/p_cscf_handler.c b/src/libcharon/plugins/p_cscf/p_cscf_handler.c
new file mode 100644
index 000000000..76633845e
--- /dev/null
+++ b/src/libcharon/plugins/p_cscf/p_cscf_handler.c
@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2016 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "p_cscf_handler.h"
+
+#include <networking/host.h>
+#include <utils/debug.h>
+
+typedef struct private_p_cscf_handler_t private_p_cscf_handler_t;
+
+/**
+ * Private data
+ */
+struct private_p_cscf_handler_t {
+
+	/**
+	 * Public interface
+	 */
+	p_cscf_handler_t public;
+};
+
+METHOD(attribute_handler_t, handle, bool,
+	private_p_cscf_handler_t *this, ike_sa_t *ike_sa,
+	configuration_attribute_type_t type, chunk_t data)
+{
+	host_t *server;
+	int family = AF_INET6;
+
+	switch (type)
+	{
+		case P_CSCF_IP4_ADDRESS:
+			family = AF_INET;
+			/* fall-through */
+		case P_CSCF_IP6_ADDRESS:
+			server = host_create_from_chunk(family, data, 0);
+			if (!server)
+			{
+				DBG1(DBG_CFG, "received invalid P-CSCF server IP");
+				return FALSE;
+			}
+			DBG1(DBG_CFG, "received P-CSCF server IP %H", server);
+			server->destroy(server);
+			return TRUE;
+		default:
+			return FALSE;
+	}
+}
+
+METHOD(attribute_handler_t, release, void,
+	private_p_cscf_handler_t *this, ike_sa_t *ike_sa,
+	configuration_attribute_type_t type, chunk_t data)
+{
+	switch (type)
+	{
+		case P_CSCF_IP4_ADDRESS:
+		case P_CSCF_IP6_ADDRESS:
+			/* nothing to do as we only log the server IPs */
+			break;
+		default:
+			break;
+	}
+}
+
+/**
+ * Data for attribute enumerator
+ */
+typedef struct {
+	enumerator_t public;
+	bool request_ipv4;
+	bool request_ipv6;
+} attr_enumerator_t;
+
+METHOD(enumerator_t, enumerate_attrs, bool,
+	attr_enumerator_t *this, configuration_attribute_type_t *type,
+	chunk_t *data)
+{
+	if (this->request_ipv4)
+	{
+		*type = P_CSCF_IP4_ADDRESS;
+		*data = chunk_empty;
+		this->request_ipv4 = FALSE;
+		return TRUE;
+	}
+	if (this->request_ipv6)
+	{
+		*type = P_CSCF_IP6_ADDRESS;
+		*data = chunk_empty;
+		this->request_ipv6 = FALSE;
+		return TRUE;
+	}
+	return FALSE;
+}
+
+/**
+ * Check if the given host has a matching address family
+ */
+static bool is_family(host_t *host, int *family)
+{
+	return host->get_family(host) == *family;
+}
+
+/**
+ * Check if a list has a host of a given family
+ */
+static bool has_host_family(linked_list_t *list, int family)
+{
+	return list->find_first(list, (void*)is_family, NULL, &family) == SUCCESS;
+}
+
+METHOD(attribute_handler_t, create_attribute_enumerator, enumerator_t *,
+	private_p_cscf_handler_t *this, ike_sa_t *ike_sa,
+	linked_list_t *vips)
+{
+	attr_enumerator_t *enumerator;
+
+	if (ike_sa->get_version(ike_sa) == IKEV1)
+	{
+		return enumerator_create_empty();
+	}
+
+	INIT(enumerator,
+		.public = {
+			.enumerate = (void*)_enumerate_attrs,
+			.destroy = (void*)free,
+		},
+	);
+	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;
+}
+
+METHOD(p_cscf_handler_t, destroy, void,
+	private_p_cscf_handler_t *this)
+{
+	free(this);
+}
+
+/**
+ * See header
+ */
+p_cscf_handler_t *p_cscf_handler_create()
+{
+	private_p_cscf_handler_t *this;
+
+	INIT(this,
+		.public = {
+			.handler = {
+				.handle = _handle,
+				.release = _release,
+				.create_attribute_enumerator = _create_attribute_enumerator,
+			},
+			.destroy = _destroy,
+		},
+	);
+
+	return &this->public;
+}
diff --git a/src/libcharon/plugins/p_cscf/p_cscf_handler.h b/src/libcharon/plugins/p_cscf/p_cscf_handler.h
new file mode 100644
index 000000000..ad4f1acce
--- /dev/null
+++ b/src/libcharon/plugins/p_cscf/p_cscf_handler.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2016 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup p_cscf_handler p_cscf_handler
+ * @{ @ingroup p_cscf
+ */
+
+#ifndef P_CSCF_HANDLER_H_
+#define P_CSCF_HANDLER_H_
+
+#include <attributes/attribute_handler.h>
+
+typedef struct p_cscf_handler_t p_cscf_handler_t;
+
+/**
+ * Attribute handler for P-CSCF server addresses.
+ */
+struct p_cscf_handler_t {
+
+	/**
+	 * Implements attribute_handler_t.
+	 */
+	attribute_handler_t handler;
+
+	/**
+	 * Destroy a p_cscf_handler_t.
+	 */
+	void (*destroy)(p_cscf_handler_t *this);
+};
+
+/**
+ * Create an p_cscf_handler_t instance.
+ */
+p_cscf_handler_t *p_cscf_handler_create();
+
+#endif /** P_CSCF_HANDLER_H_ @}*/
diff --git a/src/libcharon/plugins/p_cscf/p_cscf_plugin.c b/src/libcharon/plugins/p_cscf/p_cscf_plugin.c
new file mode 100644
index 000000000..8e2bc727e
--- /dev/null
+++ b/src/libcharon/plugins/p_cscf/p_cscf_plugin.c
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2016 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "p_cscf_plugin.h"
+#include "p_cscf_handler.h"
+
+#include <daemon.h>
+
+typedef struct private_p_cscf_plugin_t private_p_cscf_plugin_t;
+
+/**
+ * Private data
+ */
+struct private_p_cscf_plugin_t {
+
+	/**
+	 * Public interface
+	 */
+	p_cscf_plugin_t public;
+
+	/**
+	 * P-CSCF server address attribute handler
+	 */
+	p_cscf_handler_t *handler;
+};
+
+METHOD(plugin_t, get_name, char*,
+	private_p_cscf_plugin_t *this)
+{
+	return "p-cscf";
+}
+
+/**
+ * Register handler
+ */
+static bool plugin_cb(private_p_cscf_plugin_t *this,
+					  plugin_feature_t *feature, bool reg, void *cb_data)
+{
+	if (reg)
+	{
+		charon->attributes->add_handler(charon->attributes,
+										&this->handler->handler);
+	}
+	else
+	{
+		charon->attributes->remove_handler(charon->attributes,
+										   &this->handler->handler);
+	}
+	return TRUE;
+}
+
+METHOD(plugin_t, get_features, int,
+	private_p_cscf_plugin_t *this, plugin_feature_t *features[])
+{
+	static plugin_feature_t f[] = {
+		PLUGIN_CALLBACK((plugin_feature_callback_t)plugin_cb, NULL),
+			PLUGIN_PROVIDE(CUSTOM, "p-cscf"),
+	};
+	*features = f;
+	return countof(f);
+}
+
+METHOD(plugin_t, destroy, void,
+	private_p_cscf_plugin_t *this)
+{
+	this->handler->destroy(this->handler);
+	free(this);
+}
+
+/**
+ * See header
+ */
+plugin_t *p_cscf_plugin_create()
+{
+	private_p_cscf_plugin_t *this;
+
+	INIT(this,
+		.public = {
+			.plugin = {
+				.get_name = _get_name,
+				.get_features = _get_features,
+				.destroy = _destroy,
+			},
+		},
+		.handler = p_cscf_handler_create(),
+	);
+
+	return &this->public.plugin;
+}
diff --git a/src/libcharon/plugins/p_cscf/p_cscf_plugin.h b/src/libcharon/plugins/p_cscf/p_cscf_plugin.h
new file mode 100644
index 000000000..51b17674d
--- /dev/null
+++ b/src/libcharon/plugins/p_cscf/p_cscf_plugin.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2016 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup p_cscf p_cscf
+ * @ingroup cplugins
+ *
+ * @defgroup p_cscf_plugin p_cscf_plugin
+ * @{ @ingroup p_cscf
+ */
+
+#ifndef P_CSCF_PLUGIN_H_
+#define P_CSCF_PLUGIN_H_
+
+#include <plugins/plugin.h>
+
+typedef struct p_cscf_plugin_t p_cscf_plugin_t;
+
+/**
+ * Plugin that requests P-CSCF server addresses from an ePDG as specified
+ * in RFC 7651.
+ */
+struct p_cscf_plugin_t {
+
+	/**
+	 * Implements plugin interface.
+	 */
+	plugin_t plugin;
+};
+
+#endif /** P_CSCF_PLUGIN_H_ @}*/