]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * Userspace interface | |
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/kernel.h> | |
15 | #include <linux/netdevice.h> | |
16 | #include <linux/etherdevice.h> | |
17 | #include <linux/netpoll.h> | |
18 | #include <linux/ethtool.h> | |
19 | #include <linux/if_arp.h> | |
20 | #include <linux/module.h> | |
21 | #include <linux/init.h> | |
22 | #include <linux/rtnetlink.h> | |
23 | #include <linux/if_ether.h> | |
24 | #include <linux/slab.h> | |
25 | #include <net/sock.h> | |
26 | #include <linux/if_vlan.h> | |
27 | ||
28 | #include "br_private.h" | |
29 | ||
30 | /* | |
31 | * Determine initial path cost based on speed. | |
32 | * using recommendations from 802.1d standard | |
33 | * | |
34 | * Since driver might sleep need to not be holding any locks. | |
35 | */ | |
36 | static int port_cost(struct net_device *dev) | |
37 | { | |
38 | struct ethtool_cmd ecmd; | |
39 | ||
40 | if (!__ethtool_get_settings(dev, &ecmd)) { | |
41 | switch (ethtool_cmd_speed(&ecmd)) { | |
42 | case SPEED_10000: | |
43 | return 2; | |
44 | case SPEED_1000: | |
45 | return 4; | |
46 | case SPEED_100: | |
47 | return 19; | |
48 | case SPEED_10: | |
49 | return 100; | |
50 | } | |
51 | } | |
52 | ||
53 | /* Old silly heuristics based on name */ | |
54 | if (!strncmp(dev->name, "lec", 3)) | |
55 | return 7; | |
56 | ||
57 | if (!strncmp(dev->name, "plip", 4)) | |
58 | return 2500; | |
59 | ||
60 | return 100; /* assume old 10Mbps */ | |
61 | } | |
62 | ||
63 | ||
64 | /* Check for port carrier transitions. */ | |
65 | void br_port_carrier_check(struct net_bridge_port *p) | |
66 | { | |
67 | struct net_device *dev = p->dev; | |
68 | struct net_bridge *br = p->br; | |
69 | ||
70 | if (!(p->flags & BR_ADMIN_COST) && | |
71 | netif_running(dev) && netif_oper_up(dev)) | |
72 | p->path_cost = port_cost(dev); | |
73 | ||
74 | if (!netif_running(br->dev)) | |
75 | return; | |
76 | ||
77 | spin_lock_bh(&br->lock); | |
78 | if (netif_running(dev) && netif_oper_up(dev)) { | |
79 | if (p->state == BR_STATE_DISABLED) | |
80 | br_stp_enable_port(p); | |
81 | } else { | |
82 | if (p->state != BR_STATE_DISABLED) | |
83 | br_stp_disable_port(p); | |
84 | } | |
85 | spin_unlock_bh(&br->lock); | |
86 | } | |
87 | ||
88 | static void br_port_set_promisc(struct net_bridge_port *p) | |
89 | { | |
90 | int err = 0; | |
91 | ||
92 | if (br_promisc_port(p)) | |
93 | return; | |
94 | ||
95 | err = dev_set_promiscuity(p->dev, 1); | |
96 | if (err) | |
97 | return; | |
98 | ||
99 | br_fdb_unsync_static(p->br, p); | |
100 | p->flags |= BR_PROMISC; | |
101 | } | |
102 | ||
103 | static void br_port_clear_promisc(struct net_bridge_port *p) | |
104 | { | |
105 | int err; | |
106 | ||
107 | /* Check if the port is already non-promisc or if it doesn't | |
108 | * support UNICAST filtering. Without unicast filtering support | |
109 | * we'll end up re-enabling promisc mode anyway, so just check for | |
110 | * it here. | |
111 | */ | |
112 | if (!br_promisc_port(p) || !(p->dev->priv_flags & IFF_UNICAST_FLT)) | |
113 | return; | |
114 | ||
115 | /* Since we'll be clearing the promisc mode, program the port | |
116 | * first so that we don't have interruption in traffic. | |
117 | */ | |
118 | err = br_fdb_sync_static(p->br, p); | |
119 | if (err) | |
120 | return; | |
121 | ||
122 | dev_set_promiscuity(p->dev, -1); | |
123 | p->flags &= ~BR_PROMISC; | |
124 | } | |
125 | ||
126 | /* When a port is added or removed or when certain port flags | |
127 | * change, this function is called to automatically manage | |
128 | * promiscuity setting of all the bridge ports. We are always called | |
129 | * under RTNL so can skip using rcu primitives. | |
130 | */ | |
131 | void br_manage_promisc(struct net_bridge *br) | |
132 | { | |
133 | struct net_bridge_port *p; | |
134 | bool set_all = false; | |
135 | ||
136 | /* If vlan filtering is disabled or bridge interface is placed | |
137 | * into promiscuous mode, place all ports in promiscuous mode. | |
138 | */ | |
139 | if ((br->dev->flags & IFF_PROMISC) || !br_vlan_enabled(br)) | |
140 | set_all = true; | |
141 | ||
142 | list_for_each_entry(p, &br->port_list, list) { | |
143 | if (set_all) { | |
144 | br_port_set_promisc(p); | |
145 | } else { | |
146 | /* If the number of auto-ports is <= 1, then all other | |
147 | * ports will have their output configuration | |
148 | * statically specified through fdbs. Since ingress | |
149 | * on the auto-port becomes forwarding/egress to other | |
150 | * ports and egress configuration is statically known, | |
151 | * we can say that ingress configuration of the | |
152 | * auto-port is also statically known. | |
153 | * This lets us disable promiscuous mode and write | |
154 | * this config to hw. | |
155 | */ | |
156 | if (br->auto_cnt <= br_auto_port(p)) | |
157 | br_port_clear_promisc(p); | |
158 | else | |
159 | br_port_set_promisc(p); | |
160 | } | |
161 | } | |
162 | } | |
163 | ||
164 | static void nbp_update_port_count(struct net_bridge *br) | |
165 | { | |
166 | struct net_bridge_port *p; | |
167 | u32 cnt = 0; | |
168 | ||
169 | list_for_each_entry(p, &br->port_list, list) { | |
170 | if (br_auto_port(p)) | |
171 | cnt++; | |
172 | } | |
173 | if (br->auto_cnt != cnt) { | |
174 | br->auto_cnt = cnt; | |
175 | br_manage_promisc(br); | |
176 | } | |
177 | } | |
178 | ||
179 | static void nbp_delete_promisc(struct net_bridge_port *p) | |
180 | { | |
181 | /* If port is currently promiscuous, unset promiscuity. | |
182 | * Otherwise, it is a static port so remove all addresses | |
183 | * from it. | |
184 | */ | |
185 | dev_set_allmulti(p->dev, -1); | |
186 | if (br_promisc_port(p)) | |
187 | dev_set_promiscuity(p->dev, -1); | |
188 | else | |
189 | br_fdb_unsync_static(p->br, p); | |
190 | } | |
191 | ||
192 | static void release_nbp(struct kobject *kobj) | |
193 | { | |
194 | struct net_bridge_port *p | |
195 | = container_of(kobj, struct net_bridge_port, kobj); | |
196 | kfree(p); | |
197 | } | |
198 | ||
199 | static struct kobj_type brport_ktype = { | |
200 | #ifdef CONFIG_SYSFS | |
201 | .sysfs_ops = &brport_sysfs_ops, | |
202 | #endif | |
203 | .release = release_nbp, | |
204 | }; | |
205 | ||
206 | static void destroy_nbp(struct net_bridge_port *p) | |
207 | { | |
208 | struct net_device *dev = p->dev; | |
209 | ||
210 | p->br = NULL; | |
211 | p->dev = NULL; | |
212 | dev_put(dev); | |
213 | ||
214 | kobject_put(&p->kobj); | |
215 | } | |
216 | ||
217 | static void destroy_nbp_rcu(struct rcu_head *head) | |
218 | { | |
219 | struct net_bridge_port *p = | |
220 | container_of(head, struct net_bridge_port, rcu); | |
221 | destroy_nbp(p); | |
222 | } | |
223 | ||
224 | /* Delete port(interface) from bridge is done in two steps. | |
225 | * via RCU. First step, marks device as down. That deletes | |
226 | * all the timers and stops new packets from flowing through. | |
227 | * | |
228 | * Final cleanup doesn't occur until after all CPU's finished | |
229 | * processing packets. | |
230 | * | |
231 | * Protected from multiple admin operations by RTNL mutex | |
232 | */ | |
233 | static void del_nbp(struct net_bridge_port *p) | |
234 | { | |
235 | struct net_bridge *br = p->br; | |
236 | struct net_device *dev = p->dev; | |
237 | ||
238 | sysfs_remove_link(br->ifobj, p->dev->name); | |
239 | ||
240 | nbp_delete_promisc(p); | |
241 | ||
242 | spin_lock_bh(&br->lock); | |
243 | br_stp_disable_port(p); | |
244 | spin_unlock_bh(&br->lock); | |
245 | ||
246 | br_ifinfo_notify(RTM_DELLINK, p); | |
247 | ||
248 | list_del_rcu(&p->list); | |
249 | ||
250 | nbp_vlan_flush(p); | |
251 | br_fdb_delete_by_port(br, p, 1); | |
252 | nbp_update_port_count(br); | |
253 | ||
254 | dev->priv_flags &= ~IFF_BRIDGE_PORT; | |
255 | ||
256 | netdev_rx_handler_unregister(dev); | |
257 | ||
258 | netdev_upper_dev_unlink(dev, br->dev); | |
259 | ||
260 | br_multicast_del_port(p); | |
261 | ||
262 | kobject_uevent(&p->kobj, KOBJ_REMOVE); | |
263 | kobject_del(&p->kobj); | |
264 | ||
265 | br_netpoll_disable(p); | |
266 | ||
267 | call_rcu(&p->rcu, destroy_nbp_rcu); | |
268 | } | |
269 | ||
270 | /* Delete bridge device */ | |
271 | void br_dev_delete(struct net_device *dev, struct list_head *head) | |
272 | { | |
273 | struct net_bridge *br = netdev_priv(dev); | |
274 | struct net_bridge_port *p, *n; | |
275 | ||
276 | list_for_each_entry_safe(p, n, &br->port_list, list) { | |
277 | del_nbp(p); | |
278 | } | |
279 | ||
280 | br_fdb_delete_by_port(br, NULL, 1); | |
281 | ||
282 | br_vlan_flush(br); | |
283 | del_timer_sync(&br->gc_timer); | |
284 | ||
285 | br_sysfs_delbr(br->dev); | |
286 | unregister_netdevice_queue(br->dev, head); | |
287 | } | |
288 | ||
289 | /* find an available port number */ | |
290 | static int find_portno(struct net_bridge *br) | |
291 | { | |
292 | int index; | |
293 | struct net_bridge_port *p; | |
294 | unsigned long *inuse; | |
295 | ||
296 | inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long), | |
297 | GFP_KERNEL); | |
298 | if (!inuse) | |
299 | return -ENOMEM; | |
300 | ||
301 | set_bit(0, inuse); /* zero is reserved */ | |
302 | list_for_each_entry(p, &br->port_list, list) { | |
303 | set_bit(p->port_no, inuse); | |
304 | } | |
305 | index = find_first_zero_bit(inuse, BR_MAX_PORTS); | |
306 | kfree(inuse); | |
307 | ||
308 | return (index >= BR_MAX_PORTS) ? -EXFULL : index; | |
309 | } | |
310 | ||
311 | /* called with RTNL but without bridge lock */ | |
312 | static struct net_bridge_port *new_nbp(struct net_bridge *br, | |
313 | struct net_device *dev) | |
314 | { | |
315 | int index; | |
316 | struct net_bridge_port *p; | |
317 | ||
318 | index = find_portno(br); | |
319 | if (index < 0) | |
320 | return ERR_PTR(index); | |
321 | ||
322 | p = kzalloc(sizeof(*p), GFP_KERNEL); | |
323 | if (p == NULL) | |
324 | return ERR_PTR(-ENOMEM); | |
325 | ||
326 | p->br = br; | |
327 | dev_hold(dev); | |
328 | p->dev = dev; | |
329 | p->path_cost = port_cost(dev); | |
330 | p->priority = 0x8000 >> BR_PORT_BITS; | |
331 | p->port_no = index; | |
332 | p->flags = BR_LEARNING | BR_FLOOD; | |
333 | br_init_port(p); | |
334 | p->state = BR_STATE_DISABLED; | |
335 | br_stp_port_timer_init(p); | |
336 | br_multicast_add_port(p); | |
337 | ||
338 | return p; | |
339 | } | |
340 | ||
341 | int br_add_bridge(struct net *net, const char *name) | |
342 | { | |
343 | struct net_device *dev; | |
344 | int res; | |
345 | ||
346 | dev = alloc_netdev(sizeof(struct net_bridge), name, | |
347 | br_dev_setup); | |
348 | ||
349 | if (!dev) | |
350 | return -ENOMEM; | |
351 | ||
352 | dev_net_set(dev, net); | |
353 | dev->rtnl_link_ops = &br_link_ops; | |
354 | ||
355 | res = register_netdev(dev); | |
356 | if (res) | |
357 | free_netdev(dev); | |
358 | return res; | |
359 | } | |
360 | ||
361 | int br_del_bridge(struct net *net, const char *name) | |
362 | { | |
363 | struct net_device *dev; | |
364 | int ret = 0; | |
365 | ||
366 | rtnl_lock(); | |
367 | dev = __dev_get_by_name(net, name); | |
368 | if (dev == NULL) | |
369 | ret = -ENXIO; /* Could not find device */ | |
370 | ||
371 | else if (!(dev->priv_flags & IFF_EBRIDGE)) { | |
372 | /* Attempt to delete non bridge device! */ | |
373 | ret = -EPERM; | |
374 | } | |
375 | ||
376 | else if (dev->flags & IFF_UP) { | |
377 | /* Not shutdown yet. */ | |
378 | ret = -EBUSY; | |
379 | } | |
380 | ||
381 | else | |
382 | br_dev_delete(dev, NULL); | |
383 | ||
384 | rtnl_unlock(); | |
385 | return ret; | |
386 | } | |
387 | ||
388 | /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */ | |
389 | int br_min_mtu(const struct net_bridge *br) | |
390 | { | |
391 | const struct net_bridge_port *p; | |
392 | int mtu = 0; | |
393 | ||
394 | ASSERT_RTNL(); | |
395 | ||
396 | if (list_empty(&br->port_list)) | |
397 | mtu = ETH_DATA_LEN; | |
398 | else { | |
399 | list_for_each_entry(p, &br->port_list, list) { | |
400 | if (!mtu || p->dev->mtu < mtu) | |
401 | mtu = p->dev->mtu; | |
402 | } | |
403 | } | |
404 | return mtu; | |
405 | } | |
406 | ||
407 | /* | |
408 | * Recomputes features using slave's features | |
409 | */ | |
410 | netdev_features_t br_features_recompute(struct net_bridge *br, | |
411 | netdev_features_t features) | |
412 | { | |
413 | struct net_bridge_port *p; | |
414 | netdev_features_t mask; | |
415 | ||
416 | if (list_empty(&br->port_list)) | |
417 | return features; | |
418 | ||
419 | mask = features; | |
420 | features &= ~NETIF_F_ONE_FOR_ALL; | |
421 | ||
422 | list_for_each_entry(p, &br->port_list, list) { | |
423 | features = netdev_increment_features(features, | |
424 | p->dev->features, mask); | |
425 | } | |
426 | ||
427 | return features; | |
428 | } | |
429 | ||
430 | /* called with RTNL */ | |
431 | int br_add_if(struct net_bridge *br, struct net_device *dev) | |
432 | { | |
433 | struct net_bridge_port *p; | |
434 | int err = 0; | |
435 | bool changed_addr; | |
436 | ||
437 | /* Don't allow bridging non-ethernet like devices */ | |
438 | if ((dev->flags & IFF_LOOPBACK) || | |
439 | dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN || | |
440 | !is_valid_ether_addr(dev->dev_addr)) | |
441 | return -EINVAL; | |
442 | ||
443 | /* No bridging of bridges */ | |
444 | if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit) | |
445 | return -ELOOP; | |
446 | ||
447 | /* Device is already being bridged */ | |
448 | if (br_port_exists(dev)) | |
449 | return -EBUSY; | |
450 | ||
451 | /* No bridging devices that dislike that (e.g. wireless) */ | |
452 | if (dev->priv_flags & IFF_DONT_BRIDGE) | |
453 | return -EOPNOTSUPP; | |
454 | ||
455 | p = new_nbp(br, dev); | |
456 | if (IS_ERR(p)) | |
457 | return PTR_ERR(p); | |
458 | ||
459 | call_netdevice_notifiers(NETDEV_JOIN, dev); | |
460 | ||
461 | err = dev_set_allmulti(dev, 1); | |
462 | if (err) | |
463 | goto put_back; | |
464 | ||
465 | err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj), | |
466 | SYSFS_BRIDGE_PORT_ATTR); | |
467 | if (err) | |
468 | goto err1; | |
469 | ||
470 | err = br_sysfs_addif(p); | |
471 | if (err) | |
472 | goto err2; | |
473 | ||
474 | err = br_netpoll_enable(p); | |
475 | if (err) | |
476 | goto err3; | |
477 | ||
478 | err = netdev_master_upper_dev_link(dev, br->dev); | |
479 | if (err) | |
480 | goto err4; | |
481 | ||
482 | err = netdev_rx_handler_register(dev, br_handle_frame, p); | |
483 | if (err) | |
484 | goto err5; | |
485 | ||
486 | dev->priv_flags |= IFF_BRIDGE_PORT; | |
487 | ||
488 | dev_disable_lro(dev); | |
489 | ||
490 | list_add_rcu(&p->list, &br->port_list); | |
491 | ||
492 | nbp_update_port_count(br); | |
493 | ||
494 | netdev_update_features(br->dev); | |
495 | ||
496 | if (br->dev->needed_headroom < dev->needed_headroom) | |
497 | br->dev->needed_headroom = dev->needed_headroom; | |
498 | ||
499 | if (br_fdb_insert(br, p, dev->dev_addr, 0)) | |
500 | netdev_err(dev, "failed insert local address bridge forwarding table\n"); | |
501 | ||
502 | spin_lock_bh(&br->lock); | |
503 | changed_addr = br_stp_recalculate_bridge_id(br); | |
504 | ||
505 | if (netif_running(dev) && netif_oper_up(dev) && | |
506 | (br->dev->flags & IFF_UP)) | |
507 | br_stp_enable_port(p); | |
508 | spin_unlock_bh(&br->lock); | |
509 | ||
510 | br_ifinfo_notify(RTM_NEWLINK, p); | |
511 | ||
512 | if (changed_addr) | |
513 | call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev); | |
514 | ||
515 | dev_set_mtu(br->dev, br_min_mtu(br)); | |
516 | ||
517 | kobject_uevent(&p->kobj, KOBJ_ADD); | |
518 | ||
519 | return 0; | |
520 | ||
521 | err5: | |
522 | netdev_upper_dev_unlink(dev, br->dev); | |
523 | err4: | |
524 | br_netpoll_disable(p); | |
525 | err3: | |
526 | sysfs_remove_link(br->ifobj, p->dev->name); | |
527 | err2: | |
528 | kobject_put(&p->kobj); | |
529 | p = NULL; /* kobject_put frees */ | |
530 | err1: | |
531 | dev_set_allmulti(dev, -1); | |
532 | put_back: | |
533 | dev_put(dev); | |
534 | kfree(p); | |
535 | return err; | |
536 | } | |
537 | ||
538 | /* called with RTNL */ | |
539 | int br_del_if(struct net_bridge *br, struct net_device *dev) | |
540 | { | |
541 | struct net_bridge_port *p; | |
542 | bool changed_addr; | |
543 | ||
544 | p = br_port_get_rtnl(dev); | |
545 | if (!p || p->br != br) | |
546 | return -EINVAL; | |
547 | ||
548 | /* Since more than one interface can be attached to a bridge, | |
549 | * there still maybe an alternate path for netconsole to use; | |
550 | * therefore there is no reason for a NETDEV_RELEASE event. | |
551 | */ | |
552 | del_nbp(p); | |
553 | ||
554 | spin_lock_bh(&br->lock); | |
555 | changed_addr = br_stp_recalculate_bridge_id(br); | |
556 | spin_unlock_bh(&br->lock); | |
557 | ||
558 | if (changed_addr) | |
559 | call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev); | |
560 | ||
561 | netdev_update_features(br->dev); | |
562 | ||
563 | return 0; | |
564 | } | |
565 | ||
566 | void br_port_flags_change(struct net_bridge_port *p, unsigned long mask) | |
567 | { | |
568 | struct net_bridge *br = p->br; | |
569 | ||
570 | if (mask & BR_AUTO_MASK) | |
571 | nbp_update_port_count(br); | |
572 | } |