1/*
2 *	Generic parts
3 *	Linux ethernet bridge
4 *
5 *	Authors:
6 *	Lennert Buytenhek		<buytenh@gnu.org>
7 *
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
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>
19#include <linux/llc.h>
20#include <net/llc.h>
21#include <net/stp.h>
22#include <net/switchdev.h>
23
24#include "br_private.h"
25
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 */
32static 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
120static struct notifier_block br_device_notifier = {
121	.notifier_call = br_device_event
122};
123
124/* called with RTNL */
125static int br_netdev_switch_event(struct notifier_block *unused,
126				  unsigned long event, void *ptr)
127{
128	struct net_device *dev = netdev_switch_notifier_info_to_dev(ptr);
129	struct net_bridge_port *p;
130	struct net_bridge *br;
131	struct netdev_switch_notifier_fdb_info *fdb_info;
132	int err = NOTIFY_DONE;
133
134	p = br_port_get_rtnl(dev);
135	if (!p)
136		goto out;
137
138	br = p->br;
139
140	switch (event) {
141	case NETDEV_SWITCH_FDB_ADD:
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;
148	case NETDEV_SWITCH_FDB_DEL:
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
157out:
158	return err;
159}
160
161static struct notifier_block br_netdev_switch_notifier = {
162	.notifier_call = br_netdev_switch_event,
163};
164
165static 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}
179
180static struct pernet_operations br_net_ops = {
181	.exit	= br_net_exit,
182};
183
184static const struct stp_proto br_stp_proto = {
185	.rcv	= br_stp_rcv,
186};
187
188static int __init br_init(void)
189{
190	int err;
191
192	BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
193
194	err = stp_proto_register(&br_stp_proto);
195	if (err < 0) {
196		pr_err("bridge: can't register sap for STP\n");
197		return err;
198	}
199
200	err = br_fdb_init();
201	if (err)
202		goto err_out;
203
204	err = register_pernet_subsys(&br_net_ops);
205	if (err)
206		goto err_out1;
207
208	err = br_nf_core_init();
209	if (err)
210		goto err_out2;
211
212	err = register_netdevice_notifier(&br_device_notifier);
213	if (err)
214		goto err_out3;
215
216	err = register_netdev_switch_notifier(&br_netdev_switch_notifier);
217	if (err)
218		goto err_out4;
219
220	err = br_netlink_init();
221	if (err)
222		goto err_out5;
223
224	brioctl_set(br_ioctl_deviceless_stub);
225
226#if IS_ENABLED(CONFIG_ATM_LANE)
227	br_fdb_test_addr_hook = br_fdb_test_addr;
228#endif
229
230	pr_info("bridge: automatic filtering via arp/ip/ip6tables has been "
231		"deprecated. Update your scripts to load br_netfilter if you "
232		"need this.\n");
233
234	return 0;
235
236err_out5:
237	unregister_netdev_switch_notifier(&br_netdev_switch_notifier);
238err_out4:
239	unregister_netdevice_notifier(&br_device_notifier);
240err_out3:
241	br_nf_core_fini();
242err_out2:
243	unregister_pernet_subsys(&br_net_ops);
244err_out1:
245	br_fdb_fini();
246err_out:
247	stp_proto_unregister(&br_stp_proto);
248	return err;
249}
250
251static void __exit br_deinit(void)
252{
253	stp_proto_unregister(&br_stp_proto);
254	br_netlink_fini();
255	unregister_netdev_switch_notifier(&br_netdev_switch_notifier);
256	unregister_netdevice_notifier(&br_device_notifier);
257	brioctl_set(NULL);
258	unregister_pernet_subsys(&br_net_ops);
259
260	rcu_barrier(); /* Wait for completion of call_rcu()'s */
261
262	br_nf_core_fini();
263#if IS_ENABLED(CONFIG_ATM_LANE)
264	br_fdb_test_addr_hook = NULL;
265#endif
266	br_fdb_fini();
267}
268
269module_init(br_init)
270module_exit(br_deinit)
271MODULE_LICENSE("GPL");
272MODULE_VERSION(BR_VERSION);
273MODULE_ALIAS_RTNL_LINK("bridge");
274