1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Generic parts |
4 | * Linux ethernet bridge |
5 | * |
6 | * Authors: |
7 | * Lennert Buytenhek <buytenh@gnu.org> |
8 | */ |
9 | |
10 | #include <linux/module.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/netdevice.h> |
13 | #include <linux/etherdevice.h> |
14 | #include <linux/init.h> |
15 | #include <linux/llc.h> |
16 | #include <net/llc.h> |
17 | #include <net/stp.h> |
18 | #include <net/switchdev.h> |
19 | |
20 | #include "br_private.h" |
21 | |
22 | /* |
23 | * Handle changes in state of network devices enslaved to a bridge. |
24 | * |
25 | * Note: don't care about up/down if bridge itself is down, because |
26 | * port state is checked when bridge is brought up. |
27 | */ |
28 | static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr) |
29 | { |
30 | struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(info: ptr); |
31 | struct netdev_notifier_pre_changeaddr_info *prechaddr_info; |
32 | struct net_device *dev = netdev_notifier_info_to_dev(info: ptr); |
33 | struct net_bridge_port *p; |
34 | struct net_bridge *br; |
35 | bool notified = false; |
36 | bool changed_addr; |
37 | int err; |
38 | |
39 | if (netif_is_bridge_master(dev)) { |
40 | err = br_vlan_bridge_event(dev, event, ptr); |
41 | if (err) |
42 | return notifier_from_errno(err); |
43 | |
44 | if (event == NETDEV_REGISTER) { |
45 | /* register of bridge completed, add sysfs entries */ |
46 | err = br_sysfs_addbr(dev); |
47 | if (err) |
48 | return notifier_from_errno(err); |
49 | |
50 | return NOTIFY_DONE; |
51 | } |
52 | } |
53 | |
54 | /* not a port of a bridge */ |
55 | p = br_port_get_rtnl(dev); |
56 | if (!p) |
57 | return NOTIFY_DONE; |
58 | |
59 | br = p->br; |
60 | |
61 | switch (event) { |
62 | case NETDEV_CHANGEMTU: |
63 | br_mtu_auto_adjust(br); |
64 | break; |
65 | |
66 | case NETDEV_PRE_CHANGEADDR: |
67 | if (br->dev->addr_assign_type == NET_ADDR_SET) |
68 | break; |
69 | prechaddr_info = ptr; |
70 | err = dev_pre_changeaddr_notify(dev: br->dev, |
71 | addr: prechaddr_info->dev_addr, |
72 | extack); |
73 | if (err) |
74 | return notifier_from_errno(err); |
75 | break; |
76 | |
77 | case NETDEV_CHANGEADDR: |
78 | spin_lock_bh(lock: &br->lock); |
79 | br_fdb_changeaddr(p, newaddr: dev->dev_addr); |
80 | changed_addr = br_stp_recalculate_bridge_id(br); |
81 | spin_unlock_bh(lock: &br->lock); |
82 | |
83 | if (changed_addr) |
84 | call_netdevice_notifiers(val: NETDEV_CHANGEADDR, dev: br->dev); |
85 | |
86 | break; |
87 | |
88 | case NETDEV_CHANGE: |
89 | br_port_carrier_check(p, notified: ¬ified); |
90 | break; |
91 | |
92 | case NETDEV_FEAT_CHANGE: |
93 | netdev_update_features(dev: br->dev); |
94 | break; |
95 | |
96 | case NETDEV_DOWN: |
97 | spin_lock_bh(lock: &br->lock); |
98 | if (br->dev->flags & IFF_UP) { |
99 | br_stp_disable_port(p); |
100 | notified = true; |
101 | } |
102 | spin_unlock_bh(lock: &br->lock); |
103 | break; |
104 | |
105 | case NETDEV_UP: |
106 | if (netif_running(dev: br->dev) && netif_oper_up(dev)) { |
107 | spin_lock_bh(lock: &br->lock); |
108 | br_stp_enable_port(p); |
109 | notified = true; |
110 | spin_unlock_bh(lock: &br->lock); |
111 | } |
112 | break; |
113 | |
114 | case NETDEV_UNREGISTER: |
115 | br_del_if(br, dev); |
116 | break; |
117 | |
118 | case NETDEV_CHANGENAME: |
119 | err = br_sysfs_renameif(p); |
120 | if (err) |
121 | return notifier_from_errno(err); |
122 | break; |
123 | |
124 | case NETDEV_PRE_TYPE_CHANGE: |
125 | /* Forbid underlying device to change its type. */ |
126 | return NOTIFY_BAD; |
127 | |
128 | case NETDEV_RESEND_IGMP: |
129 | /* Propagate to master device */ |
130 | call_netdevice_notifiers(val: event, dev: br->dev); |
131 | break; |
132 | } |
133 | |
134 | if (event != NETDEV_UNREGISTER) |
135 | br_vlan_port_event(p, event); |
136 | |
137 | /* Events that may cause spanning tree to refresh */ |
138 | if (!notified && (event == NETDEV_CHANGEADDR || event == NETDEV_UP || |
139 | event == NETDEV_CHANGE || event == NETDEV_DOWN)) |
140 | br_ifinfo_notify(RTM_NEWLINK, NULL, port: p); |
141 | |
142 | return NOTIFY_DONE; |
143 | } |
144 | |
145 | static struct notifier_block br_device_notifier = { |
146 | .notifier_call = br_device_event |
147 | }; |
148 | |
149 | /* called with RTNL or RCU */ |
150 | static int br_switchdev_event(struct notifier_block *unused, |
151 | unsigned long event, void *ptr) |
152 | { |
153 | struct net_device *dev = switchdev_notifier_info_to_dev(info: ptr); |
154 | struct net_bridge_port *p; |
155 | struct net_bridge *br; |
156 | struct switchdev_notifier_fdb_info *fdb_info; |
157 | int err = NOTIFY_DONE; |
158 | |
159 | p = br_port_get_rtnl_rcu(dev); |
160 | if (!p) |
161 | goto out; |
162 | |
163 | br = p->br; |
164 | |
165 | switch (event) { |
166 | case SWITCHDEV_FDB_ADD_TO_BRIDGE: |
167 | fdb_info = ptr; |
168 | err = br_fdb_external_learn_add(br, p, addr: fdb_info->addr, |
169 | vid: fdb_info->vid, |
170 | locked: fdb_info->locked, swdev_notify: false); |
171 | if (err) { |
172 | err = notifier_from_errno(err); |
173 | break; |
174 | } |
175 | br_fdb_offloaded_set(br, p, addr: fdb_info->addr, |
176 | vid: fdb_info->vid, offloaded: fdb_info->offloaded); |
177 | break; |
178 | case SWITCHDEV_FDB_DEL_TO_BRIDGE: |
179 | fdb_info = ptr; |
180 | err = br_fdb_external_learn_del(br, p, addr: fdb_info->addr, |
181 | vid: fdb_info->vid, swdev_notify: false); |
182 | if (err) |
183 | err = notifier_from_errno(err); |
184 | break; |
185 | case SWITCHDEV_FDB_OFFLOADED: |
186 | fdb_info = ptr; |
187 | br_fdb_offloaded_set(br, p, addr: fdb_info->addr, |
188 | vid: fdb_info->vid, offloaded: fdb_info->offloaded); |
189 | break; |
190 | case SWITCHDEV_FDB_FLUSH_TO_BRIDGE: |
191 | fdb_info = ptr; |
192 | /* Don't delete static entries */ |
193 | br_fdb_delete_by_port(br, p, vid: fdb_info->vid, do_all: 0); |
194 | break; |
195 | } |
196 | |
197 | out: |
198 | return err; |
199 | } |
200 | |
201 | static struct notifier_block br_switchdev_notifier = { |
202 | .notifier_call = br_switchdev_event, |
203 | }; |
204 | |
205 | /* called under rtnl_mutex */ |
206 | static int br_switchdev_blocking_event(struct notifier_block *nb, |
207 | unsigned long event, void *ptr) |
208 | { |
209 | struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(info: ptr); |
210 | struct net_device *dev = switchdev_notifier_info_to_dev(info: ptr); |
211 | struct switchdev_notifier_brport_info *brport_info; |
212 | const struct switchdev_brport *b; |
213 | struct net_bridge_port *p; |
214 | int err = NOTIFY_DONE; |
215 | |
216 | p = br_port_get_rtnl(dev); |
217 | if (!p) |
218 | goto out; |
219 | |
220 | switch (event) { |
221 | case SWITCHDEV_BRPORT_OFFLOADED: |
222 | brport_info = ptr; |
223 | b = &brport_info->brport; |
224 | |
225 | err = br_switchdev_port_offload(p, dev: b->dev, ctx: b->ctx, |
226 | atomic_nb: b->atomic_nb, blocking_nb: b->blocking_nb, |
227 | tx_fwd_offload: b->tx_fwd_offload, extack); |
228 | err = notifier_from_errno(err); |
229 | break; |
230 | case SWITCHDEV_BRPORT_UNOFFLOADED: |
231 | brport_info = ptr; |
232 | b = &brport_info->brport; |
233 | |
234 | br_switchdev_port_unoffload(p, ctx: b->ctx, atomic_nb: b->atomic_nb, |
235 | blocking_nb: b->blocking_nb); |
236 | break; |
237 | case SWITCHDEV_BRPORT_REPLAY: |
238 | brport_info = ptr; |
239 | b = &brport_info->brport; |
240 | |
241 | err = br_switchdev_port_replay(p, dev: b->dev, ctx: b->ctx, atomic_nb: b->atomic_nb, |
242 | blocking_nb: b->blocking_nb, extack); |
243 | err = notifier_from_errno(err); |
244 | break; |
245 | } |
246 | |
247 | out: |
248 | return err; |
249 | } |
250 | |
251 | static struct notifier_block br_switchdev_blocking_notifier = { |
252 | .notifier_call = br_switchdev_blocking_event, |
253 | }; |
254 | |
255 | /* br_boolopt_toggle - change user-controlled boolean option |
256 | * |
257 | * @br: bridge device |
258 | * @opt: id of the option to change |
259 | * @on: new option value |
260 | * @extack: extack for error messages |
261 | * |
262 | * Changes the value of the respective boolean option to @on taking care of |
263 | * any internal option value mapping and configuration. |
264 | */ |
265 | int br_boolopt_toggle(struct net_bridge *br, enum br_boolopt_id opt, bool on, |
266 | struct netlink_ext_ack *extack) |
267 | { |
268 | int err = 0; |
269 | |
270 | switch (opt) { |
271 | case BR_BOOLOPT_NO_LL_LEARN: |
272 | br_opt_toggle(br, opt: BROPT_NO_LL_LEARN, on); |
273 | break; |
274 | case BR_BOOLOPT_MCAST_VLAN_SNOOPING: |
275 | err = br_multicast_toggle_vlan_snooping(br, on, extack); |
276 | break; |
277 | case BR_BOOLOPT_MST_ENABLE: |
278 | err = br_mst_set_enabled(br, on, extack); |
279 | break; |
280 | default: |
281 | /* shouldn't be called with unsupported options */ |
282 | WARN_ON(1); |
283 | break; |
284 | } |
285 | |
286 | return err; |
287 | } |
288 | |
289 | int br_boolopt_get(const struct net_bridge *br, enum br_boolopt_id opt) |
290 | { |
291 | switch (opt) { |
292 | case BR_BOOLOPT_NO_LL_LEARN: |
293 | return br_opt_get(br, opt: BROPT_NO_LL_LEARN); |
294 | case BR_BOOLOPT_MCAST_VLAN_SNOOPING: |
295 | return br_opt_get(br, opt: BROPT_MCAST_VLAN_SNOOPING_ENABLED); |
296 | case BR_BOOLOPT_MST_ENABLE: |
297 | return br_opt_get(br, opt: BROPT_MST_ENABLED); |
298 | default: |
299 | /* shouldn't be called with unsupported options */ |
300 | WARN_ON(1); |
301 | break; |
302 | } |
303 | |
304 | return 0; |
305 | } |
306 | |
307 | int br_boolopt_multi_toggle(struct net_bridge *br, |
308 | struct br_boolopt_multi *bm, |
309 | struct netlink_ext_ack *extack) |
310 | { |
311 | unsigned long bitmap = bm->optmask; |
312 | int err = 0; |
313 | int opt_id; |
314 | |
315 | for_each_set_bit(opt_id, &bitmap, BR_BOOLOPT_MAX) { |
316 | bool on = !!(bm->optval & BIT(opt_id)); |
317 | |
318 | err = br_boolopt_toggle(br, opt: opt_id, on, extack); |
319 | if (err) { |
320 | br_debug(br, "boolopt multi-toggle error: option: %d current: %d new: %d error: %d\n" , |
321 | opt_id, br_boolopt_get(br, opt_id), on, err); |
322 | break; |
323 | } |
324 | } |
325 | |
326 | return err; |
327 | } |
328 | |
329 | void br_boolopt_multi_get(const struct net_bridge *br, |
330 | struct br_boolopt_multi *bm) |
331 | { |
332 | u32 optval = 0; |
333 | int opt_id; |
334 | |
335 | for (opt_id = 0; opt_id < BR_BOOLOPT_MAX; opt_id++) |
336 | optval |= (br_boolopt_get(br, opt: opt_id) << opt_id); |
337 | |
338 | bm->optval = optval; |
339 | bm->optmask = GENMASK((BR_BOOLOPT_MAX - 1), 0); |
340 | } |
341 | |
342 | /* private bridge options, controlled by the kernel */ |
343 | void br_opt_toggle(struct net_bridge *br, enum net_bridge_opts opt, bool on) |
344 | { |
345 | bool cur = !!br_opt_get(br, opt); |
346 | |
347 | br_debug(br, "toggle option: %d state: %d -> %d\n" , |
348 | opt, cur, on); |
349 | |
350 | if (cur == on) |
351 | return; |
352 | |
353 | if (on) |
354 | set_bit(nr: opt, addr: &br->options); |
355 | else |
356 | clear_bit(nr: opt, addr: &br->options); |
357 | } |
358 | |
359 | static void __net_exit br_net_exit_batch_rtnl(struct list_head *net_list, |
360 | struct list_head *dev_to_kill) |
361 | { |
362 | struct net_device *dev; |
363 | struct net *net; |
364 | |
365 | ASSERT_RTNL(); |
366 | list_for_each_entry(net, net_list, exit_list) |
367 | for_each_netdev(net, dev) |
368 | if (netif_is_bridge_master(dev)) |
369 | br_dev_delete(dev, list: dev_to_kill); |
370 | } |
371 | |
372 | static struct pernet_operations br_net_ops = { |
373 | .exit_batch_rtnl = br_net_exit_batch_rtnl, |
374 | }; |
375 | |
376 | static const struct stp_proto br_stp_proto = { |
377 | .rcv = br_stp_rcv, |
378 | }; |
379 | |
380 | static int __init br_init(void) |
381 | { |
382 | int err; |
383 | |
384 | BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > sizeof_field(struct sk_buff, cb)); |
385 | |
386 | err = stp_proto_register(proto: &br_stp_proto); |
387 | if (err < 0) { |
388 | pr_err("bridge: can't register sap for STP\n" ); |
389 | return err; |
390 | } |
391 | |
392 | err = br_fdb_init(); |
393 | if (err) |
394 | goto err_out; |
395 | |
396 | err = register_pernet_subsys(&br_net_ops); |
397 | if (err) |
398 | goto err_out1; |
399 | |
400 | err = br_nf_core_init(); |
401 | if (err) |
402 | goto err_out2; |
403 | |
404 | err = register_netdevice_notifier(nb: &br_device_notifier); |
405 | if (err) |
406 | goto err_out3; |
407 | |
408 | err = register_switchdev_notifier(nb: &br_switchdev_notifier); |
409 | if (err) |
410 | goto err_out4; |
411 | |
412 | err = register_switchdev_blocking_notifier(nb: &br_switchdev_blocking_notifier); |
413 | if (err) |
414 | goto err_out5; |
415 | |
416 | err = br_netlink_init(); |
417 | if (err) |
418 | goto err_out6; |
419 | |
420 | brioctl_set(hook: br_ioctl_stub); |
421 | |
422 | #if IS_ENABLED(CONFIG_ATM_LANE) |
423 | br_fdb_test_addr_hook = br_fdb_test_addr; |
424 | #endif |
425 | |
426 | #if IS_MODULE(CONFIG_BRIDGE_NETFILTER) |
427 | pr_info("bridge: filtering via arp/ip/ip6tables is no longer available " |
428 | "by default. Update your scripts to load br_netfilter if you " |
429 | "need this.\n" ); |
430 | #endif |
431 | |
432 | return 0; |
433 | |
434 | err_out6: |
435 | unregister_switchdev_blocking_notifier(nb: &br_switchdev_blocking_notifier); |
436 | err_out5: |
437 | unregister_switchdev_notifier(nb: &br_switchdev_notifier); |
438 | err_out4: |
439 | unregister_netdevice_notifier(nb: &br_device_notifier); |
440 | err_out3: |
441 | br_nf_core_fini(); |
442 | err_out2: |
443 | unregister_pernet_subsys(&br_net_ops); |
444 | err_out1: |
445 | br_fdb_fini(); |
446 | err_out: |
447 | stp_proto_unregister(proto: &br_stp_proto); |
448 | return err; |
449 | } |
450 | |
451 | static void __exit br_deinit(void) |
452 | { |
453 | stp_proto_unregister(proto: &br_stp_proto); |
454 | br_netlink_fini(); |
455 | unregister_switchdev_blocking_notifier(nb: &br_switchdev_blocking_notifier); |
456 | unregister_switchdev_notifier(nb: &br_switchdev_notifier); |
457 | unregister_netdevice_notifier(nb: &br_device_notifier); |
458 | brioctl_set(NULL); |
459 | unregister_pernet_subsys(&br_net_ops); |
460 | |
461 | rcu_barrier(); /* Wait for completion of call_rcu()'s */ |
462 | |
463 | br_nf_core_fini(); |
464 | #if IS_ENABLED(CONFIG_ATM_LANE) |
465 | br_fdb_test_addr_hook = NULL; |
466 | #endif |
467 | br_fdb_fini(); |
468 | } |
469 | |
470 | module_init(br_init) |
471 | module_exit(br_deinit) |
472 | MODULE_LICENSE("GPL" ); |
473 | MODULE_VERSION(BR_VERSION); |
474 | MODULE_ALIAS_RTNL_LINK("bridge" ); |
475 | MODULE_DESCRIPTION("Ethernet bridge driver" ); |
476 | |