[mirror_ubuntu-zesty-kernel.git] / net / bridge / br.c

/*
 *	Generic parts
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *
 *	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.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/init.h>
#include <linux/llc.h>
#include <net/llc.h>
#include <net/stp.h>
#include <net/switchdev.h>

#include "br_private.h"

/*
 * Handle changes in state of network devices enslaved to a bridge.
 *
 * Note: don't care about up/down if bridge itself is down, because
 *     port state is checked when bridge is brought up.
 */
static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
{
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
	struct net_bridge_port *p;
	struct net_bridge *br;
	bool changed_addr;
	int err;

	/* register of bridge completed, add sysfs entries */
	if ((dev->priv_flags & IFF_EBRIDGE) && event == NETDEV_REGISTER) {
		br_sysfs_addbr(dev);
		return NOTIFY_DONE;
	}

	/* not a port of a bridge */
	p = br_port_get_rtnl(dev);
	if (!p)
		return NOTIFY_DONE;

	br = p->br;

	switch (event) {
	case NETDEV_CHANGEMTU:
		dev_set_mtu(br->dev, br_min_mtu(br));
		break;

	case NETDEV_CHANGEADDR:
		spin_lock_bh(&br->lock);
		br_fdb_changeaddr(p, dev->dev_addr);
		changed_addr = br_stp_recalculate_bridge_id(br);
		spin_unlock_bh(&br->lock);

		if (changed_addr)
			call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);

		break;

	case NETDEV_CHANGE:
		br_port_carrier_check(p);
		break;

	case NETDEV_FEAT_CHANGE:
		netdev_update_features(br->dev);
		break;

	case NETDEV_DOWN:
		spin_lock_bh(&br->lock);
		if (br->dev->flags & IFF_UP)
			br_stp_disable_port(p);
		spin_unlock_bh(&br->lock);
		break;

	case NETDEV_UP:
		if (netif_running(br->dev) && netif_oper_up(dev)) {
			spin_lock_bh(&br->lock);
			br_stp_enable_port(p);
			spin_unlock_bh(&br->lock);
		}
		break;

	case NETDEV_UNREGISTER:
		br_del_if(br, dev);
		break;

	case NETDEV_CHANGENAME:
		err = br_sysfs_renameif(p);
		if (err)
			return notifier_from_errno(err);
		break;

	case NETDEV_PRE_TYPE_CHANGE:
		/* Forbid underlaying device to change its type. */
		return NOTIFY_BAD;

	case NETDEV_RESEND_IGMP:
		/* Propagate to master device */
		call_netdevice_notifiers(event, br->dev);
		break;
	}

	/* Events that may cause spanning tree to refresh */
	if (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
	    event == NETDEV_CHANGE || event == NETDEV_DOWN)
		br_ifinfo_notify(RTM_NEWLINK, p);

	return NOTIFY_DONE;
}

static struct notifier_block br_device_notifier = {
	.notifier_call = br_device_event
};

/* called with RTNL */
static int br_switchdev_event(struct notifier_block *unused,
			      unsigned long event, void *ptr)
{
	struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
	struct net_bridge_port *p;
	struct net_bridge *br;
	struct switchdev_notifier_fdb_info *fdb_info;
	int err = NOTIFY_DONE;

	p = br_port_get_rtnl(dev);
	if (!p)
		goto out;

	br = p->br;

	switch (event) {
	case SWITCHDEV_FDB_ADD:
		fdb_info = ptr;
		err = br_fdb_external_learn_add(br, p, fdb_info->addr,
						fdb_info->vid);
		if (err)
			err = notifier_from_errno(err);
		break;
	case SWITCHDEV_FDB_DEL:
		fdb_info = ptr;
		err = br_fdb_external_learn_del(br, p, fdb_info->addr,
						fdb_info->vid);
		if (err)
			err = notifier_from_errno(err);
		break;
	}

out:
	return err;
}

static struct notifier_block br_switchdev_notifier = {
	.notifier_call = br_switchdev_event,
};

static void __net_exit br_net_exit(struct net *net)
{
	struct net_device *dev;
	LIST_HEAD(list);

	rtnl_lock();
	for_each_netdev(net, dev)
		if (dev->priv_flags & IFF_EBRIDGE)
			br_dev_delete(dev, &list);

	unregister_netdevice_many(&list);
	rtnl_unlock();

}

static struct pernet_operations br_net_ops = {
	.exit	= br_net_exit,
};

static const struct stp_proto br_stp_proto = {
	.rcv	= br_stp_rcv,
};

static int __init br_init(void)
{
	int err;

	BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));

	err = stp_proto_register(&br_stp_proto);
	if (err < 0) {
		pr_err("bridge: can't register sap for STP\n");
		return err;
	}

	err = br_fdb_init();
	if (err)
		goto err_out;

	err = register_pernet_subsys(&br_net_ops);
	if (err)
		goto err_out1;

	err = br_nf_core_init();
	if (err)
		goto err_out2;

	err = register_netdevice_notifier(&br_device_notifier);
	if (err)
		goto err_out3;

	err = register_switchdev_notifier(&br_switchdev_notifier);
	if (err)
		goto err_out4;

	err = br_netlink_init();
	if (err)
		goto err_out5;

	brioctl_set(br_ioctl_deviceless_stub);

#if IS_ENABLED(CONFIG_ATM_LANE)
	br_fdb_test_addr_hook = br_fdb_test_addr;
#endif

#if IS_MODULE(CONFIG_BRIDGE_NETFILTER)
	pr_info("bridge: filtering via arp/ip/ip6tables is no longer available "
		"by default. Update your scripts to load br_netfilter if you "
		"need this.\n");
#endif

	return 0;

err_out5:
	unregister_switchdev_notifier(&br_switchdev_notifier);
err_out4:
	unregister_netdevice_notifier(&br_device_notifier);
err_out3:
	br_nf_core_fini();
err_out2:
	unregister_pernet_subsys(&br_net_ops);
err_out1:
	br_fdb_fini();
err_out:
	stp_proto_unregister(&br_stp_proto);
	return err;
}

static void __exit br_deinit(void)
{
	stp_proto_unregister(&br_stp_proto);
	br_netlink_fini();
	unregister_switchdev_notifier(&br_switchdev_notifier);
	unregister_netdevice_notifier(&br_device_notifier);
	brioctl_set(NULL);
	unregister_pernet_subsys(&br_net_ops);

	rcu_barrier(); /* Wait for completion of call_rcu()'s */

	br_nf_core_fini();
#if IS_ENABLED(CONFIG_ATM_LANE)
	br_fdb_test_addr_hook = NULL;
#endif
	br_fdb_fini();
}

module_init(br_init)
module_exit(br_deinit)
MODULE_LICENSE("GPL");
MODULE_VERSION(BR_VERSION);
MODULE_ALIAS_RTNL_LINK("bridge");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Generic parts
	3	* Linux ethernet bridge
	4	*
	5	* Authors:
	6	* Lennert Buytenhek <buytenh@gnu.org>
	7	*
1da177e4 LT	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version
	11	* 2 of the License, or (at your option) any later version.
	12	*/
	13
1da177e4 LT	14	#include <linux/module.h>
	15	#include <linux/kernel.h>
	16	#include <linux/netdevice.h>
	17	#include <linux/etherdevice.h>
	18	#include <linux/init.h>
cf0f02d0 SH	19	#include <linux/llc.h>
cf0f02d0 SH	20	#include <net/llc.h>
7c85fbf0	21	#include <net/stp.h>
3aeb6617	22	#include <net/switchdev.h>
1da177e4 LT	23
	24	#include "br_private.h"
	25
b1282726 CW	26	/*
	27	* Handle changes in state of network devices enslaved to a bridge.
	28	*
	29	* Note: don't care about up/down if bridge itself is down, because
	30	* port state is checked when bridge is brought up.
	31	*/
	32	static int br_device_event(struct notifier_block unused, unsigned long event, void ptr)
	33	{
	34	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
	35	struct net_bridge_port *p;
	36	struct net_bridge *br;
	37	bool changed_addr;
	38	int err;
	39
	40	/* register of bridge completed, add sysfs entries */
	41	if ((dev->priv_flags & IFF_EBRIDGE) && event == NETDEV_REGISTER) {
	42	br_sysfs_addbr(dev);
	43	return NOTIFY_DONE;
	44	}
	45
	46	/* not a port of a bridge */
	47	p = br_port_get_rtnl(dev);
	48	if (!p)
	49	return NOTIFY_DONE;
	50
	51	br = p->br;
	52
	53	switch (event) {
	54	case NETDEV_CHANGEMTU:
	55	dev_set_mtu(br->dev, br_min_mtu(br));
	56	break;
	57
	58	case NETDEV_CHANGEADDR:
	59	spin_lock_bh(&br->lock);
	60	br_fdb_changeaddr(p, dev->dev_addr);
	61	changed_addr = br_stp_recalculate_bridge_id(br);
	62	spin_unlock_bh(&br->lock);
	63
	64	if (changed_addr)
	65	call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
	66
	67	break;
	68
	69	case NETDEV_CHANGE:
	70	br_port_carrier_check(p);
	71	break;
	72
	73	case NETDEV_FEAT_CHANGE:
	74	netdev_update_features(br->dev);
	75	break;
	76
	77	case NETDEV_DOWN:
	78	spin_lock_bh(&br->lock);
	79	if (br->dev->flags & IFF_UP)
	80	br_stp_disable_port(p);
	81	spin_unlock_bh(&br->lock);
	82	break;
	83
	84	case NETDEV_UP:
	85	if (netif_running(br->dev) && netif_oper_up(dev)) {
	86	spin_lock_bh(&br->lock);
	87	br_stp_enable_port(p);
	88	spin_unlock_bh(&br->lock);
	89	}
90	break;
91
92	case NETDEV_UNREGISTER:
93	br_del_if(br, dev);
94	break;
95
96	case NETDEV_CHANGENAME:
97	err = br_sysfs_renameif(p);
98	if (err)
99	return notifier_from_errno(err);
100	break;
101
102	case NETDEV_PRE_TYPE_CHANGE:
103	/* Forbid underlaying device to change its type. */
104	return NOTIFY_BAD;
105
106	case NETDEV_RESEND_IGMP:
107	/* Propagate to master device */
108	call_netdevice_notifiers(event, br->dev);
109	break;
110	}
111
112	/* Events that may cause spanning tree to refresh */
113	if (event == NETDEV_CHANGEADDR \|\| event == NETDEV_UP \|\|
114	event == NETDEV_CHANGE \|\| event == NETDEV_DOWN)
115	br_ifinfo_notify(RTM_NEWLINK, p);
116
117	return NOTIFY_DONE;
118	}
119
120	static struct notifier_block br_device_notifier = {
121	.notifier_call = br_device_event
122	};
123
4f2c6ae5	124	/* called with RTNL */
ebb9a03a JP	125	static int br_switchdev_event(struct notifier_block *unused,
ebb9a03a JP	126	unsigned long event, void *ptr)
3aeb6617	127	{
ebb9a03a	128	struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
3aeb6617 JP	129	struct net_bridge_port *p;
3aeb6617 JP	130	struct net_bridge *br;
ebb9a03a	131	struct switchdev_notifier_fdb_info *fdb_info;
3aeb6617 JP	132	int err = NOTIFY_DONE;
3aeb6617 JP	133
3aeb6617 JP	134	p = br_port_get_rtnl(dev);
	135	if (!p)
	136	goto out;
	137
	138	br = p->br;
	139
	140	switch (event) {
ebb9a03a	141	case SWITCHDEV_FDB_ADD:
3aeb6617 JP	142	fdb_info = ptr;
	143	err = br_fdb_external_learn_add(br, p, fdb_info->addr,
	144	fdb_info->vid);
	145	if (err)
	146	err = notifier_from_errno(err);
	147	break;
ebb9a03a	148	case SWITCHDEV_FDB_DEL:
3aeb6617 JP	149	fdb_info = ptr;
	150	err = br_fdb_external_learn_del(br, p, fdb_info->addr,
	151	fdb_info->vid);
	152	if (err)
	153	err = notifier_from_errno(err);
	154	break;
	155	}
	156
	157	out:
3aeb6617 JP	158	return err;
	159	}
	160
ebb9a03a JP	161	static struct notifier_block br_switchdev_notifier = {
ebb9a03a JP	162	.notifier_call = br_switchdev_event,
3aeb6617 JP	163	};
3aeb6617 JP	164
b86f81cc WC	165	static void __net_exit br_net_exit(struct net *net)
	166	{
	167	struct net_device *dev;
	168	LIST_HEAD(list);
	169
	170	rtnl_lock();
	171	for_each_netdev(net, dev)
	172	if (dev->priv_flags & IFF_EBRIDGE)
	173	br_dev_delete(dev, &list);
	174
	175	unregister_netdevice_many(&list);
	176	rtnl_unlock();
	177
	178	}
cf0f02d0	179
712d6954 AD	180	static struct pernet_operations br_net_ops = {
	181	.exit = br_net_exit,
	182	};
	183
b86f81cc WC	184	static const struct stp_proto br_stp_proto = {
	185	.rcv = br_stp_rcv,
	186	};
	187
1da177e4 LT	188	static int __init br_init(void)
1da177e4 LT	189	{
c0909713 SH	190	int err;
c0909713 SH	191
71e168b1 FW	192	BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
71e168b1 FW	193
7c85fbf0 PM	194	err = stp_proto_register(&br_stp_proto);
7c85fbf0 PM	195	if (err < 0) {
28a16c97	196	pr_err("bridge: can't register sap for STP\n");
7c85fbf0	197	return err;
cf0f02d0 SH	198	}
cf0f02d0 SH	199
87a596e0 AM	200	err = br_fdb_init();
87a596e0 AM	201	if (err)
17efdd45	202	goto err_out;
1da177e4	203
712d6954	204	err = register_pernet_subsys(&br_net_ops);
c0909713 SH	205	if (err)
	206	goto err_out1;
	207
34666d46	208	err = br_nf_core_init();
c0909713 SH	209	if (err)
	210	goto err_out2;
	211
712d6954	212	err = register_netdevice_notifier(&br_device_notifier);
32fe21c0 TG	213	if (err)
	214	goto err_out3;
	215
ebb9a03a	216	err = register_switchdev_notifier(&br_switchdev_notifier);
712d6954 AD	217	if (err)
	218	goto err_out4;
	219
3aeb6617 JP	220	err = br_netlink_init();
	221	if (err)
	222	goto err_out5;
	223
1da177e4	224	brioctl_set(br_ioctl_deviceless_stub);
1da177e4	225
e6373c4c	226	#if IS_ENABLED(CONFIG_ATM_LANE)
da678292 MM	227	br_fdb_test_addr_hook = br_fdb_test_addr;
da678292 MM	228	#endif
1da177e4	229
d4ef9f72 SA	230	#if IS_MODULE(CONFIG_BRIDGE_NETFILTER)
	231	pr_info("bridge: filtering via arp/ip/ip6tables is no longer available "
	232	"by default. Update your scripts to load br_netfilter if you "
34666d46	233	"need this.\n");
d4ef9f72	234	#endif
34666d46	235
1da177e4	236	return 0;
34666d46	237
3aeb6617	238	err_out5:
ebb9a03a	239	unregister_switchdev_notifier(&br_switchdev_notifier);
712d6954	240	err_out4:
32fe21c0	241	unregister_netdevice_notifier(&br_device_notifier);
712d6954	242	err_out3:
34666d46	243	br_nf_core_fini();
712d6954 AD	244	err_out2:
712d6954 AD	245	unregister_pernet_subsys(&br_net_ops);
c0909713	246	err_out1:
17efdd45 PE	247	br_fdb_fini();
17efdd45 PE	248	err_out:
7c85fbf0	249	stp_proto_unregister(&br_stp_proto);
c0909713	250	return err;
1da177e4 LT	251	}
	252
	253	static void __exit br_deinit(void)
	254	{
7c85fbf0	255	stp_proto_unregister(&br_stp_proto);
11dc1f36	256	br_netlink_fini();
ebb9a03a	257	unregister_switchdev_notifier(&br_switchdev_notifier);
1da177e4 LT	258	unregister_netdevice_notifier(&br_device_notifier);
1da177e4 LT	259	brioctl_set(NULL);
712d6954	260	unregister_pernet_subsys(&br_net_ops);
1da177e4	261
473c22d7	262	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1da177e4	263
34666d46	264	br_nf_core_fini();
e6373c4c	265	#if IS_ENABLED(CONFIG_ATM_LANE)
da678292 MM	266	br_fdb_test_addr_hook = NULL;
da678292 MM	267	#endif
1da177e4 LT	268	br_fdb_fini();
	269	}
	270
1da177e4 LT	271	module_init(br_init)
	272	module_exit(br_deinit)
	273	MODULE_LICENSE("GPL");
8cbb512e	274	MODULE_VERSION(BR_VERSION);
bb900b27	275	MODULE_ALIAS_RTNL_LINK("bridge");