src/ipv6pd.c - nest-guard/1.0/connman - Git at Google

 /*
  *
  *  Connection Manager
  *
  *  Copyright (C) 2013  Intel Corporation. All rights reserved.
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2 as
  *  published by the Free Software Foundation.
  *
  *  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.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  *
  */

 #ifdef HAVE_CONFIG_H
 #include <config.h>
 #endif

 #include <errno.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>
 #include <stdio.h>

 #include "connman.h"

 #include <gdhcp/gdhcp.h>

 #define DEFAULT_ROUTER_LIFETIME 180  /* secs */
 #define DEFAULT_RA_INTERVAL 120  /* secs */

 static int bridge_index = -1;
 static guint timer_uplink;
 static guint timer_ra;
 static char *default_interface;
 static GSList *prefixes;
 static GHashTable *timer_hash;
 static void *rs_context;

 static int setup_prefix_delegation(struct connman_service *service);
 static void dhcpv6_callback(struct connman_network *network,
 			enum __connman_dhcpv6_status status, gpointer data);

 static int enable_ipv6_forward(bool enable)
 {
 	FILE *f;

 	f = fopen("/proc/sys/net/ipv6/ip_forward", "r+");
 	if (!f)
 		return -errno;

 	if (enable)
 		fprintf(f, "1");
 	else
 		fprintf(f, "0");

 	fclose(f);

 	return 0;
 }

 static gboolean send_ra(gpointer data)
 {
 	__connman_inet_ipv6_send_ra(bridge_index, NULL, prefixes,
 					DEFAULT_ROUTER_LIFETIME);

 	return TRUE;
 }

 static void start_ra(int ifindex, GSList *prefix)
 {
 	if (prefixes)
 		g_slist_free_full(prefixes, g_free);

 	prefixes = g_dhcpv6_copy_prefixes(prefix);

 	enable_ipv6_forward(true);

 	if (timer_ra > 0)
 		g_source_remove(timer_ra);

 	send_ra(NULL);

 	timer_ra = g_timeout_add_seconds(DEFAULT_RA_INTERVAL, send_ra, NULL);
 }

 static void stop_ra(int ifindex)
 {
 	__connman_inet_ipv6_send_ra(ifindex, NULL, prefixes, 0);

 	if (timer_ra > 0) {
 		g_source_remove(timer_ra);
 		timer_ra = 0;
 	}

 	enable_ipv6_forward(false);

 	if (prefixes) {
 		g_slist_free_full(prefixes, g_free);
 		prefixes = NULL;
 	}
 }

 static void rs_received(struct nd_router_solicit *reply,
 			unsigned int length, void *user_data)
 {
 	GDHCPIAPrefix *prefix;
 	GSList *list;

 	if (!prefixes)
 		return;

 	DBG("");

 	for (list = prefixes; list; list = list->next) {
 		prefix = list->data;

 		prefix->valid -= time(NULL) - prefix->expire;
 		prefix->preferred -= time(NULL) - prefix->expire;
 	}

 	__connman_inet_ipv6_send_ra(bridge_index, NULL, prefixes,
 					DEFAULT_ROUTER_LIFETIME);
 }

 static gboolean do_setup(gpointer data)
 {
 	int ret;

 	timer_uplink = 0;

 	if (!default_interface)
 		DBG("No uplink connection, retrying prefix delegation");

 	ret = setup_prefix_delegation(__connman_service_get_default());
 	if (ret < 0 && ret != -EINPROGRESS)
 		return TRUE; /* delegation error, try again */

 	return FALSE;
 }

 static void dhcpv6_renew_callback(struct connman_network *network,
 				enum __connman_dhcpv6_status status,
 				gpointer data)
 {
 	DBG("network %p status %d data %p", network, status, data);

 	if (status == CONNMAN_DHCPV6_STATUS_SUCCEED)
 		dhcpv6_callback(network, status, data);
 	else
 		setup_prefix_delegation(__connman_service_get_default());
 }

 static void cleanup(void)
 {
 	if (timer_uplink != 0) {
 		g_source_remove(timer_uplink);
 		timer_uplink = 0;
 	}

 	if (timer_hash) {
 		g_hash_table_destroy(timer_hash);
 		timer_hash = NULL;
 	}

 	if (prefixes) {
 		g_slist_free_full(prefixes, g_free);
 		prefixes = NULL;
 	}
 }

 static void dhcpv6_callback(struct connman_network *network,
 			enum __connman_dhcpv6_status status, gpointer data)
 {
 	GSList *prefix_list = data;

 	DBG("network %p status %d data %p", network, status, data);

 	if (status == CONNMAN_DHCPV6_STATUS_FAIL) {
 		DBG("Prefix delegation request failed");
 		cleanup();
 		return;
 	}

 	if (!prefix_list) {
 		DBG("No prefixes, retrying");
 		if (timer_uplink == 0)
 			timer_uplink = g_timeout_add_seconds(10, do_setup,
 									NULL);
 		return;
 	}

 	/*
 	 * After we have got a list of prefixes, we can start to send router
 	 * advertisements (RA) to tethering interface.
 	 */
 	start_ra(bridge_index, prefix_list);

 	if (__connman_dhcpv6_start_pd_renew(network,
 					dhcpv6_renew_callback) == -ETIMEDOUT)
 		dhcpv6_renew_callback(network, CONNMAN_DHCPV6_STATUS_FAIL,
 									NULL);
 }

 static int setup_prefix_delegation(struct connman_service *service)
 {
 	struct connman_ipconfig *ipconfig;
 	char *interface;
 	int err = 0, ifindex;

 	if (!service) {
 		/*
 		 * We do not have uplink connection. We just wait until
 		 * default interface is updated.
 		 */
 		return -EINPROGRESS;
 	}

 	interface = connman_service_get_interface(service);

 	DBG("interface %s bridge_index %d", interface, bridge_index);

 	if (default_interface) {
 		stop_ra(bridge_index);

 		ifindex = connman_inet_ifindex(default_interface);
 		__connman_dhcpv6_stop_pd(ifindex);
 	}

 	g_free(default_interface);

 	ipconfig = __connman_service_get_ip6config(service);
 	if (!__connman_ipconfig_ipv6_is_enabled(ipconfig)) {
 		g_free(interface);
 		default_interface = NULL;
 		return -EPFNOSUPPORT;
 	}

 	default_interface = interface;

 	if (default_interface) {
 		ifindex = connman_inet_ifindex(default_interface);

 		/*
 		 * Try to get a IPv6 prefix so we can start to advertise it.
 		 */
 		err = __connman_dhcpv6_start_pd(ifindex, prefixes,
 						dhcpv6_callback);
 		if (err < 0)
 			DBG("prefix delegation %d/%s", err, strerror(-err));
 	}

 	return err;
 }

 static void cleanup_timer(gpointer user_data)
 {
 	guint timer = GPOINTER_TO_UINT(user_data);

 	g_source_remove(timer);
 }

 static void update_default_interface(struct connman_service *service)
 {
 	setup_prefix_delegation(service);
 }

 static void update_ipconfig(struct connman_service *service,
 				struct connman_ipconfig *ipconfig)
 {
 	if (!service || service != __connman_service_get_default())
 		return;

 	if (ipconfig != __connman_service_get_ip6config(service))
 		return;

 	if (!__connman_ipconfig_ipv6_is_enabled(ipconfig)) {
 		if (default_interface) {
 			int ifindex;

 			ifindex = connman_inet_ifindex(default_interface);
 			__connman_dhcpv6_stop_pd(ifindex);

 			g_free(default_interface);
 			default_interface = NULL;
 		}

 		DBG("No IPv6 support for interface index %d",
 			__connman_ipconfig_get_index(ipconfig));
 		return;
 	}

 	/*
 	 * Did we had PD activated already? If not, then start it.
 	 */
 	if (!default_interface) {
 		DBG("IPv6 ipconfig %p changed for interface index %d", ipconfig,
 			__connman_ipconfig_get_index(ipconfig));

 		setup_prefix_delegation(service);
 	}
 }

 static struct connman_notifier pd_notifier = {
 	.name			= "IPv6 prefix delegation",
 	.default_changed	= update_default_interface,
 	.ipconfig_changed	= update_ipconfig,
 };

 int __connman_ipv6pd_setup(const char *bridge)
 {
 	struct connman_service *service;
 	int err;

 	if (!connman_inet_is_ipv6_supported())
 		return -EPFNOSUPPORT;

 	if (bridge_index >= 0) {
 		DBG("Prefix delegation already running");
 		return -EALREADY;
 	}

 	err = connman_notifier_register(&pd_notifier);
 	if (err < 0)
 		return err;

 	bridge_index = connman_inet_ifindex(bridge);

 	timer_hash = g_hash_table_new_full(g_direct_hash, g_direct_equal,
 						NULL, cleanup_timer);

 	err = __connman_inet_ipv6_start_recv_rs(bridge_index, rs_received,
 						NULL, &rs_context);
 	if (err < 0)
 		DBG("Cannot receive router solicitation %d/%s",
 			err, strerror(-err));

 	service = __connman_service_get_default();
 	if (service) {
 		/*
 		 * We have an uplink connection already, try to use it.
 		 */
 		return setup_prefix_delegation(service);
 	}

 	/*
 	 * The prefix delegation is started after have got the uplink
 	 * connection up i.e., when the default service is setup in which
 	 * case the update_default_interface() will be called.
 	 */
 	return -EINPROGRESS;
 }

 void __connman_ipv6pd_cleanup(void)
 {
 	int ifindex;

 	if (!connman_inet_is_ipv6_supported())
 		return;

 	connman_notifier_unregister(&pd_notifier);

 	__connman_inet_ipv6_stop_recv_rs(rs_context);
 	rs_context = NULL;

 	cleanup();

 	stop_ra(bridge_index);

 	if (default_interface) {
 		ifindex = connman_inet_ifindex(default_interface);
 		__connman_dhcpv6_stop_pd(ifindex);
 		g_free(default_interface);
 		default_interface = NULL;
 	}

 	bridge_index = -1;
 }
	/*
	*
	* Connection Manager
	*
	* Copyright (C) 2013 Intel Corporation. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*
	* 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.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*
	*/

	#ifdef HAVE_CONFIG_H
	#include <config.h>
	#endif

	#include <errno.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <unistd.h>
	#include <stdio.h>

	#include "connman.h"

	#include <gdhcp/gdhcp.h>

	#define DEFAULT_ROUTER_LIFETIME 180 /* secs */
	#define DEFAULT_RA_INTERVAL 120 /* secs */

	static int bridge_index = -1;
	static guint timer_uplink;
	static guint timer_ra;
	static char *default_interface;
	static GSList *prefixes;
	static GHashTable *timer_hash;
	static void *rs_context;

	static int setup_prefix_delegation(struct connman_service *service);
	static void dhcpv6_callback(struct connman_network *network,
	enum __connman_dhcpv6_status status, gpointer data);

	static int enable_ipv6_forward(bool enable)
	{
	FILE *f;

	f = fopen("/proc/sys/net/ipv6/ip_forward", "r+");
	if (!f)
	return -errno;

	if (enable)
	fprintf(f, "1");
	else
	fprintf(f, "0");

	fclose(f);

	return 0;
	}

	static gboolean send_ra(gpointer data)
	{
	__connman_inet_ipv6_send_ra(bridge_index, NULL, prefixes,
	DEFAULT_ROUTER_LIFETIME);

	return TRUE;
	}

	static void start_ra(int ifindex, GSList *prefix)
	{
	if (prefixes)
	g_slist_free_full(prefixes, g_free);

	prefixes = g_dhcpv6_copy_prefixes(prefix);

	enable_ipv6_forward(true);

	if (timer_ra > 0)
	g_source_remove(timer_ra);

	send_ra(NULL);

	timer_ra = g_timeout_add_seconds(DEFAULT_RA_INTERVAL, send_ra, NULL);
	}

	static void stop_ra(int ifindex)
	{
	__connman_inet_ipv6_send_ra(ifindex, NULL, prefixes, 0);

	if (timer_ra > 0) {
	g_source_remove(timer_ra);
	timer_ra = 0;
	}

	enable_ipv6_forward(false);

	if (prefixes) {
	g_slist_free_full(prefixes, g_free);
	prefixes = NULL;
	}
	}

	static void rs_received(struct nd_router_solicit *reply,
	unsigned int length, void *user_data)
	{
	GDHCPIAPrefix *prefix;
	GSList *list;

	if (!prefixes)
	return;

	DBG("");

	for (list = prefixes; list; list = list->next) {
	prefix = list->data;

	prefix->valid -= time(NULL) - prefix->expire;
	prefix->preferred -= time(NULL) - prefix->expire;
	}

	__connman_inet_ipv6_send_ra(bridge_index, NULL, prefixes,
	DEFAULT_ROUTER_LIFETIME);
	}

	static gboolean do_setup(gpointer data)
	{
	int ret;

	timer_uplink = 0;

	if (!default_interface)
	DBG("No uplink connection, retrying prefix delegation");

	ret = setup_prefix_delegation(__connman_service_get_default());
	if (ret < 0 && ret != -EINPROGRESS)
	return TRUE; /* delegation error, try again */

	return FALSE;
	}

	static void dhcpv6_renew_callback(struct connman_network *network,
	enum __connman_dhcpv6_status status,
	gpointer data)
	{
	DBG("network %p status %d data %p", network, status, data);

	if (status == CONNMAN_DHCPV6_STATUS_SUCCEED)
	dhcpv6_callback(network, status, data);
	else
	setup_prefix_delegation(__connman_service_get_default());
	}

	static void cleanup(void)
	{
	if (timer_uplink != 0) {
	g_source_remove(timer_uplink);
	timer_uplink = 0;
	}

	if (timer_hash) {
	g_hash_table_destroy(timer_hash);
	timer_hash = NULL;
	}

	if (prefixes) {
	g_slist_free_full(prefixes, g_free);
	prefixes = NULL;
	}
	}

	static void dhcpv6_callback(struct connman_network *network,
	enum __connman_dhcpv6_status status, gpointer data)
	{
	GSList *prefix_list = data;

	DBG("network %p status %d data %p", network, status, data);

	if (status == CONNMAN_DHCPV6_STATUS_FAIL) {
	DBG("Prefix delegation request failed");
	cleanup();
	return;
	}

	if (!prefix_list) {
	DBG("No prefixes, retrying");
	if (timer_uplink == 0)
	timer_uplink = g_timeout_add_seconds(10, do_setup,
	NULL);
	return;
	}

	/*
	* After we have got a list of prefixes, we can start to send router
	* advertisements (RA) to tethering interface.
	*/
	start_ra(bridge_index, prefix_list);

	if (__connman_dhcpv6_start_pd_renew(network,
	dhcpv6_renew_callback) == -ETIMEDOUT)
	dhcpv6_renew_callback(network, CONNMAN_DHCPV6_STATUS_FAIL,
	NULL);
	}

	static int setup_prefix_delegation(struct connman_service *service)
	{
	struct connman_ipconfig *ipconfig;
	char *interface;
	int err = 0, ifindex;

	if (!service) {
	/*
	* We do not have uplink connection. We just wait until
	* default interface is updated.
	*/
	return -EINPROGRESS;
	}

	interface = connman_service_get_interface(service);

	DBG("interface %s bridge_index %d", interface, bridge_index);

	if (default_interface) {
	stop_ra(bridge_index);

	ifindex = connman_inet_ifindex(default_interface);
	__connman_dhcpv6_stop_pd(ifindex);
	}

	g_free(default_interface);

	ipconfig = __connman_service_get_ip6config(service);
	if (!__connman_ipconfig_ipv6_is_enabled(ipconfig)) {
	g_free(interface);
	default_interface = NULL;
	return -EPFNOSUPPORT;
	}

	default_interface = interface;

	if (default_interface) {
	ifindex = connman_inet_ifindex(default_interface);

	/*
	* Try to get a IPv6 prefix so we can start to advertise it.
	*/
	err = __connman_dhcpv6_start_pd(ifindex, prefixes,
	dhcpv6_callback);
	if (err < 0)
	DBG("prefix delegation %d/%s", err, strerror(-err));
	}

	return err;
	}

	static void cleanup_timer(gpointer user_data)
	{
	guint timer = GPOINTER_TO_UINT(user_data);

	g_source_remove(timer);
	}

	static void update_default_interface(struct connman_service *service)
	{
	setup_prefix_delegation(service);
	}

	static void update_ipconfig(struct connman_service *service,
	struct connman_ipconfig *ipconfig)
	{
	if (!service \|\| service != __connman_service_get_default())
	return;

	if (ipconfig != __connman_service_get_ip6config(service))
	return;

	if (!__connman_ipconfig_ipv6_is_enabled(ipconfig)) {
	if (default_interface) {
	int ifindex;

	ifindex = connman_inet_ifindex(default_interface);
	__connman_dhcpv6_stop_pd(ifindex);

	g_free(default_interface);
	default_interface = NULL;
	}

	DBG("No IPv6 support for interface index %d",
	__connman_ipconfig_get_index(ipconfig));
	return;
	}

	/*
	* Did we had PD activated already? If not, then start it.
	*/
	if (!default_interface) {
	DBG("IPv6 ipconfig %p changed for interface index %d", ipconfig,
	__connman_ipconfig_get_index(ipconfig));

	setup_prefix_delegation(service);
	}
	}

	static struct connman_notifier pd_notifier = {
	.name = "IPv6 prefix delegation",
	.default_changed = update_default_interface,
	.ipconfig_changed = update_ipconfig,
	};

	int __connman_ipv6pd_setup(const char *bridge)
	{
	struct connman_service *service;
	int err;

	if (!connman_inet_is_ipv6_supported())
	return -EPFNOSUPPORT;

	if (bridge_index >= 0) {
	DBG("Prefix delegation already running");
	return -EALREADY;
	}

	err = connman_notifier_register(&pd_notifier);
	if (err < 0)
	return err;

	bridge_index = connman_inet_ifindex(bridge);

	timer_hash = g_hash_table_new_full(g_direct_hash, g_direct_equal,
	NULL, cleanup_timer);

	err = __connman_inet_ipv6_start_recv_rs(bridge_index, rs_received,
	NULL, &rs_context);
	if (err < 0)
	DBG("Cannot receive router solicitation %d/%s",
	err, strerror(-err));

	service = __connman_service_get_default();
	if (service) {
	/*
	* We have an uplink connection already, try to use it.
	*/
	return setup_prefix_delegation(service);
	}

	/*
	* The prefix delegation is started after have got the uplink
	* connection up i.e., when the default service is setup in which
	* case the update_default_interface() will be called.
	*/
	return -EINPROGRESS;
	}

	void __connman_ipv6pd_cleanup(void)
	{
	int ifindex;

	if (!connman_inet_is_ipv6_supported())
	return;

	connman_notifier_unregister(&pd_notifier);

	__connman_inet_ipv6_stop_recv_rs(rs_context);
	rs_context = NULL;

	cleanup();

	stop_ra(bridge_index);

	if (default_interface) {
	ifindex = connman_inet_ifindex(default_interface);
	__connman_dhcpv6_stop_pd(ifindex);
	g_free(default_interface);
	default_interface = NULL;
	}

	bridge_index = -1;
	}