summaryrefslogtreecommitdiffstats
path: root/net/bridge/br.c
blob: 360ad66c21e95794f1eaa59d2aee599f56f3f39a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
/*
 *	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 notified = false;
	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:
		br_mtu_auto_adjust(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, &notified);
		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);
			notified = true;
		}
		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);
			notified = true;
			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 (!notified && (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
			  event == NETDEV_CHANGE || event == NETDEV_DOWN))
		br_ifinfo_notify(RTM_NEWLINK, NULL, p);

	return NOTIFY_DONE;
}

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

/* called with RTNL or RCU */
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_rcu(dev);
	if (!p)
		goto out;

	br = p->br;

	switch (event) {
	case SWITCHDEV_FDB_ADD_TO_BRIDGE:
		fdb_info = ptr;
		err = br_fdb_external_learn_add(br, p, fdb_info->addr,
						fdb_info->vid, false);
		if (err) {
			err = notifier_from_errno(err);
			break;
		}
		br_fdb_offloaded_set(br, p, fdb_info->addr,
				     fdb_info->vid, true);
		break;
	case SWITCHDEV_FDB_DEL_TO_BRIDGE:
		fdb_info = ptr;
		err = br_fdb_external_learn_del(br, p, fdb_info->addr,
						fdb_info->vid, false);
		if (err)
			err = notifier_from_errno(err);
		break;
	case SWITCHDEV_FDB_OFFLOADED:
		fdb_info = ptr;
		br_fdb_offloaded_set(br, p, fdb_info->addr,
				     fdb_info->vid, fdb_info->offloaded);
		break;
	}

out:
	return err;
}

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

void br_opt_toggle(struct net_bridge *br, enum net_bridge_opts opt, bool on)
{
	bool cur = !!br_opt_get(br, opt);

	br_debug(br, "toggle option: %d state: %d -> %d\n",
		 opt, cur, on);

	if (cur == on)
		return;

	if (on)
		set_bit(opt, &br->options);
	else
		clear_bit(opt, &br->options);
}

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");