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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/netpoll.h>
17#include <linux/ethtool.h>
18#include <linux/if_arp.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/rtnetlink.h>
22#include <linux/if_ether.h>
23#include <linux/slab.h>
24#include <net/sock.h>
25
26#include "br_private.h"
27
28/*
29 * Determine initial path cost based on speed.
30 * using recommendations from 802.1d standard
31 *
32 * Since driver might sleep need to not be holding any locks.
33 */
34static int port_cost(struct net_device *dev)
35{
36 if (dev->ethtool_ops && dev->ethtool_ops->get_settings) {
37 struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET, };
38
39 if (!dev_ethtool_get_settings(dev, &ecmd)) {
40 switch (ethtool_cmd_speed(&ecmd)) {
41 case SPEED_10000:
42 return 2;
43 case SPEED_1000:
44 return 4;
45 case SPEED_100:
46 return 19;
47 case SPEED_10:
48 return 100;
49 }
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 transistions. */
65void 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 (netif_running(dev) && netif_carrier_ok(dev))
71 p->path_cost = port_cost(dev);
72
73 if (!netif_running(br->dev))
74 return;
75
76 spin_lock_bh(&br->lock);
77 if (netif_running(dev) && netif_carrier_ok(dev)) {
78 if (p->state == BR_STATE_DISABLED)
79 br_stp_enable_port(p);
80 } else {
81 if (p->state != BR_STATE_DISABLED)
82 br_stp_disable_port(p);
83 }
84 spin_unlock_bh(&br->lock);
85}
86
87static void release_nbp(struct kobject *kobj)
88{
89 struct net_bridge_port *p
90 = container_of(kobj, struct net_bridge_port, kobj);
91 kfree(p);
92}
93
94static struct kobj_type brport_ktype = {
95#ifdef CONFIG_SYSFS
96 .sysfs_ops = &brport_sysfs_ops,
97#endif
98 .release = release_nbp,
99};
100
101static void destroy_nbp(struct net_bridge_port *p)
102{
103 struct net_device *dev = p->dev;
104
105 p->br = NULL;
106 p->dev = NULL;
107 dev_put(dev);
108
109 kobject_put(&p->kobj);
110}
111
112static void destroy_nbp_rcu(struct rcu_head *head)
113{
114 struct net_bridge_port *p =
115 container_of(head, struct net_bridge_port, rcu);
116 destroy_nbp(p);
117}
118
119/* Delete port(interface) from bridge is done in two steps.
120 * via RCU. First step, marks device as down. That deletes
121 * all the timers and stops new packets from flowing through.
122 *
123 * Final cleanup doesn't occur until after all CPU's finished
124 * processing packets.
125 *
126 * Protected from multiple admin operations by RTNL mutex
127 */
128static void del_nbp(struct net_bridge_port *p)
129{
130 struct net_bridge *br = p->br;
131 struct net_device *dev = p->dev;
132
133 sysfs_remove_link(br->ifobj, p->dev->name);
134
135 dev_set_promiscuity(dev, -1);
136
137 spin_lock_bh(&br->lock);
138 br_stp_disable_port(p);
139 spin_unlock_bh(&br->lock);
140
141 br_ifinfo_notify(RTM_DELLINK, p);
142
143 br_fdb_delete_by_port(br, p, 1);
144
145 list_del_rcu(&p->list);
146
147 dev->priv_flags &= ~IFF_BRIDGE_PORT;
148
149 netdev_rx_handler_unregister(dev);
150 synchronize_net();
151
152 netdev_set_master(dev, NULL);
153
154 br_multicast_del_port(p);
155
156 kobject_uevent(&p->kobj, KOBJ_REMOVE);
157 kobject_del(&p->kobj);
158
159 br_netpoll_disable(p);
160
161 call_rcu(&p->rcu, destroy_nbp_rcu);
162}
163
164/* Delete bridge device */
165void br_dev_delete(struct net_device *dev, struct list_head *head)
166{
167 struct net_bridge *br = netdev_priv(dev);
168 struct net_bridge_port *p, *n;
169
170 list_for_each_entry_safe(p, n, &br->port_list, list) {
171 del_nbp(p);
172 }
173
174 del_timer_sync(&br->gc_timer);
175
176 br_sysfs_delbr(br->dev);
177 unregister_netdevice_queue(br->dev, head);
178}
179
180/* find an available port number */
181static int find_portno(struct net_bridge *br)
182{
183 int index;
184 struct net_bridge_port *p;
185 unsigned long *inuse;
186
187 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
188 GFP_KERNEL);
189 if (!inuse)
190 return -ENOMEM;
191
192 set_bit(0, inuse); /* zero is reserved */
193 list_for_each_entry(p, &br->port_list, list) {
194 set_bit(p->port_no, inuse);
195 }
196 index = find_first_zero_bit(inuse, BR_MAX_PORTS);
197 kfree(inuse);
198
199 return (index >= BR_MAX_PORTS) ? -EXFULL : index;
200}
201
202/* called with RTNL but without bridge lock */
203static struct net_bridge_port *new_nbp(struct net_bridge *br,
204 struct net_device *dev)
205{
206 int index;
207 struct net_bridge_port *p;
208
209 index = find_portno(br);
210 if (index < 0)
211 return ERR_PTR(index);
212
213 p = kzalloc(sizeof(*p), GFP_KERNEL);
214 if (p == NULL)
215 return ERR_PTR(-ENOMEM);
216
217 p->br = br;
218 dev_hold(dev);
219 p->dev = dev;
220 p->path_cost = port_cost(dev);
221 p->priority = 0x8000 >> BR_PORT_BITS;
222 p->port_no = index;
223 p->flags = 0;
224 br_init_port(p);
225 p->state = BR_STATE_DISABLED;
226 br_stp_port_timer_init(p);
227 br_multicast_add_port(p);
228
229 return p;
230}
231
232int br_add_bridge(struct net *net, const char *name)
233{
234 struct net_device *dev;
235 int res;
236
237 dev = alloc_netdev(sizeof(struct net_bridge), name,
238 br_dev_setup);
239
240 if (!dev)
241 return -ENOMEM;
242
243 dev_net_set(dev, net);
244
245 res = register_netdev(dev);
246 if (res)
247 free_netdev(dev);
248 return res;
249}
250
251int br_del_bridge(struct net *net, const char *name)
252{
253 struct net_device *dev;
254 int ret = 0;
255
256 rtnl_lock();
257 dev = __dev_get_by_name(net, name);
258 if (dev == NULL)
259 ret = -ENXIO; /* Could not find device */
260
261 else if (!(dev->priv_flags & IFF_EBRIDGE)) {
262 /* Attempt to delete non bridge device! */
263 ret = -EPERM;
264 }
265
266 else if (dev->flags & IFF_UP) {
267 /* Not shutdown yet. */
268 ret = -EBUSY;
269 }
270
271 else
272 br_dev_delete(dev, NULL);
273
274 rtnl_unlock();
275 return ret;
276}
277
278/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
279int br_min_mtu(const struct net_bridge *br)
280{
281 const struct net_bridge_port *p;
282 int mtu = 0;
283
284 ASSERT_RTNL();
285
286 if (list_empty(&br->port_list))
287 mtu = ETH_DATA_LEN;
288 else {
289 list_for_each_entry(p, &br->port_list, list) {
290 if (!mtu || p->dev->mtu < mtu)
291 mtu = p->dev->mtu;
292 }
293 }
294 return mtu;
295}
296
297/*
298 * Recomputes features using slave's features
299 */
300u32 br_features_recompute(struct net_bridge *br, u32 features)
301{
302 struct net_bridge_port *p;
303 u32 mask;
304
305 if (list_empty(&br->port_list))
306 return features;
307
308 mask = features;
309 features &= ~NETIF_F_ONE_FOR_ALL;
310
311 list_for_each_entry(p, &br->port_list, list) {
312 features = netdev_increment_features(features,
313 p->dev->features, mask);
314 }
315
316 return features;
317}
318
319/* called with RTNL */
320int br_add_if(struct net_bridge *br, struct net_device *dev)
321{
322 struct net_bridge_port *p;
323 int err = 0;
324 bool changed_addr;
325
326 /* Don't allow bridging non-ethernet like devices */
327 if ((dev->flags & IFF_LOOPBACK) ||
328 dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN)
329 return -EINVAL;
330
331 /* No bridging of bridges */
332 if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
333 return -ELOOP;
334
335 /* Device is already being bridged */
336 if (br_port_exists(dev))
337 return -EBUSY;
338
339 /* No bridging devices that dislike that (e.g. wireless) */
340 if (dev->priv_flags & IFF_DONT_BRIDGE)
341 return -EOPNOTSUPP;
342
343 p = new_nbp(br, dev);
344 if (IS_ERR(p))
345 return PTR_ERR(p);
346
347 call_netdevice_notifiers(NETDEV_JOIN, dev);
348
349 err = dev_set_promiscuity(dev, 1);
350 if (err)
351 goto put_back;
352
353 err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
354 SYSFS_BRIDGE_PORT_ATTR);
355 if (err)
356 goto err0;
357
358 err = br_fdb_insert(br, p, dev->dev_addr);
359 if (err)
360 goto err1;
361
362 err = br_sysfs_addif(p);
363 if (err)
364 goto err2;
365
366 if (br_netpoll_info(br) && ((err = br_netpoll_enable(p))))
367 goto err3;
368
369 err = netdev_set_master(dev, br->dev);
370 if (err)
371 goto err3;
372
373 err = netdev_rx_handler_register(dev, br_handle_frame, p);
374 if (err)
375 goto err4;
376
377 dev->priv_flags |= IFF_BRIDGE_PORT;
378
379 dev_disable_lro(dev);
380
381 list_add_rcu(&p->list, &br->port_list);
382
383 netdev_update_features(br->dev);
384
385 spin_lock_bh(&br->lock);
386 changed_addr = br_stp_recalculate_bridge_id(br);
387
388 if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
389 (br->dev->flags & IFF_UP))
390 br_stp_enable_port(p);
391 spin_unlock_bh(&br->lock);
392
393 br_ifinfo_notify(RTM_NEWLINK, p);
394
395 if (changed_addr)
396 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
397
398 dev_set_mtu(br->dev, br_min_mtu(br));
399
400 kobject_uevent(&p->kobj, KOBJ_ADD);
401
402 return 0;
403
404err4:
405 netdev_set_master(dev, NULL);
406err3:
407 sysfs_remove_link(br->ifobj, p->dev->name);
408err2:
409 br_fdb_delete_by_port(br, p, 1);
410err1:
411 kobject_put(&p->kobj);
412 p = NULL; /* kobject_put frees */
413err0:
414 dev_set_promiscuity(dev, -1);
415put_back:
416 dev_put(dev);
417 kfree(p);
418 return err;
419}
420
421/* called with RTNL */
422int br_del_if(struct net_bridge *br, struct net_device *dev)
423{
424 struct net_bridge_port *p;
425 bool changed_addr;
426
427 p = br_port_get_rtnl(dev);
428 if (!p || p->br != br)
429 return -EINVAL;
430
431 del_nbp(p);
432
433 spin_lock_bh(&br->lock);
434 changed_addr = br_stp_recalculate_bridge_id(br);
435 spin_unlock_bh(&br->lock);
436
437 if (changed_addr)
438 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
439
440 netdev_update_features(br->dev);
441
442 return 0;
443}
444
445void __net_exit br_net_exit(struct net *net)
446{
447 struct net_device *dev;
448 LIST_HEAD(list);
449
450 rtnl_lock();
451 for_each_netdev(net, dev)
452 if (dev->priv_flags & IFF_EBRIDGE)
453 br_dev_delete(dev, &list);
454
455 unregister_netdevice_many(&list);
456 rtnl_unlock();
457
458}
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/dsa.h>
26#include <net/sock.h>
27#include <linux/if_vlan.h>
28#include <net/switchdev.h>
29
30#include "br_private.h"
31
32/*
33 * Determine initial path cost based on speed.
34 * using recommendations from 802.1d standard
35 *
36 * Since driver might sleep need to not be holding any locks.
37 */
38static int port_cost(struct net_device *dev)
39{
40 struct ethtool_link_ksettings ecmd;
41
42 if (!__ethtool_get_link_ksettings(dev, &ecmd)) {
43 switch (ecmd.base.speed) {
44 case SPEED_10000:
45 return 2;
46 case SPEED_1000:
47 return 4;
48 case SPEED_100:
49 return 19;
50 case SPEED_10:
51 return 100;
52 }
53 }
54
55 /* Old silly heuristics based on name */
56 if (!strncmp(dev->name, "lec", 3))
57 return 7;
58
59 if (!strncmp(dev->name, "plip", 4))
60 return 2500;
61
62 return 100; /* assume old 10Mbps */
63}
64
65
66/* Check for port carrier transitions. */
67void br_port_carrier_check(struct net_bridge_port *p)
68{
69 struct net_device *dev = p->dev;
70 struct net_bridge *br = p->br;
71
72 if (!(p->flags & BR_ADMIN_COST) &&
73 netif_running(dev) && netif_oper_up(dev))
74 p->path_cost = port_cost(dev);
75
76 if (!netif_running(br->dev))
77 return;
78
79 spin_lock_bh(&br->lock);
80 if (netif_running(dev) && netif_oper_up(dev)) {
81 if (p->state == BR_STATE_DISABLED)
82 br_stp_enable_port(p);
83 } else {
84 if (p->state != BR_STATE_DISABLED)
85 br_stp_disable_port(p);
86 }
87 spin_unlock_bh(&br->lock);
88}
89
90static void br_port_set_promisc(struct net_bridge_port *p)
91{
92 int err = 0;
93
94 if (br_promisc_port(p))
95 return;
96
97 err = dev_set_promiscuity(p->dev, 1);
98 if (err)
99 return;
100
101 br_fdb_unsync_static(p->br, p);
102 p->flags |= BR_PROMISC;
103}
104
105static void br_port_clear_promisc(struct net_bridge_port *p)
106{
107 int err;
108
109 /* Check if the port is already non-promisc or if it doesn't
110 * support UNICAST filtering. Without unicast filtering support
111 * we'll end up re-enabling promisc mode anyway, so just check for
112 * it here.
113 */
114 if (!br_promisc_port(p) || !(p->dev->priv_flags & IFF_UNICAST_FLT))
115 return;
116
117 /* Since we'll be clearing the promisc mode, program the port
118 * first so that we don't have interruption in traffic.
119 */
120 err = br_fdb_sync_static(p->br, p);
121 if (err)
122 return;
123
124 dev_set_promiscuity(p->dev, -1);
125 p->flags &= ~BR_PROMISC;
126}
127
128/* When a port is added or removed or when certain port flags
129 * change, this function is called to automatically manage
130 * promiscuity setting of all the bridge ports. We are always called
131 * under RTNL so can skip using rcu primitives.
132 */
133void br_manage_promisc(struct net_bridge *br)
134{
135 struct net_bridge_port *p;
136 bool set_all = false;
137
138 /* If vlan filtering is disabled or bridge interface is placed
139 * into promiscuous mode, place all ports in promiscuous mode.
140 */
141 if ((br->dev->flags & IFF_PROMISC) || !br_vlan_enabled(br->dev))
142 set_all = true;
143
144 list_for_each_entry(p, &br->port_list, list) {
145 if (set_all) {
146 br_port_set_promisc(p);
147 } else {
148 /* If the number of auto-ports is <= 1, then all other
149 * ports will have their output configuration
150 * statically specified through fdbs. Since ingress
151 * on the auto-port becomes forwarding/egress to other
152 * ports and egress configuration is statically known,
153 * we can say that ingress configuration of the
154 * auto-port is also statically known.
155 * This lets us disable promiscuous mode and write
156 * this config to hw.
157 */
158 if (br->auto_cnt == 0 ||
159 (br->auto_cnt == 1 && br_auto_port(p)))
160 br_port_clear_promisc(p);
161 else
162 br_port_set_promisc(p);
163 }
164 }
165}
166
167static void nbp_update_port_count(struct net_bridge *br)
168{
169 struct net_bridge_port *p;
170 u32 cnt = 0;
171
172 list_for_each_entry(p, &br->port_list, list) {
173 if (br_auto_port(p))
174 cnt++;
175 }
176 if (br->auto_cnt != cnt) {
177 br->auto_cnt = cnt;
178 br_manage_promisc(br);
179 }
180}
181
182static void nbp_delete_promisc(struct net_bridge_port *p)
183{
184 /* If port is currently promiscuous, unset promiscuity.
185 * Otherwise, it is a static port so remove all addresses
186 * from it.
187 */
188 dev_set_allmulti(p->dev, -1);
189 if (br_promisc_port(p))
190 dev_set_promiscuity(p->dev, -1);
191 else
192 br_fdb_unsync_static(p->br, p);
193}
194
195static void release_nbp(struct kobject *kobj)
196{
197 struct net_bridge_port *p
198 = container_of(kobj, struct net_bridge_port, kobj);
199 kfree(p);
200}
201
202static struct kobj_type brport_ktype = {
203#ifdef CONFIG_SYSFS
204 .sysfs_ops = &brport_sysfs_ops,
205#endif
206 .release = release_nbp,
207};
208
209static void destroy_nbp(struct net_bridge_port *p)
210{
211 struct net_device *dev = p->dev;
212
213 p->br = NULL;
214 p->dev = NULL;
215 dev_put(dev);
216
217 kobject_put(&p->kobj);
218}
219
220static void destroy_nbp_rcu(struct rcu_head *head)
221{
222 struct net_bridge_port *p =
223 container_of(head, struct net_bridge_port, rcu);
224 destroy_nbp(p);
225}
226
227static unsigned get_max_headroom(struct net_bridge *br)
228{
229 unsigned max_headroom = 0;
230 struct net_bridge_port *p;
231
232 list_for_each_entry(p, &br->port_list, list) {
233 unsigned dev_headroom = netdev_get_fwd_headroom(p->dev);
234
235 if (dev_headroom > max_headroom)
236 max_headroom = dev_headroom;
237 }
238
239 return max_headroom;
240}
241
242static void update_headroom(struct net_bridge *br, int new_hr)
243{
244 struct net_bridge_port *p;
245
246 list_for_each_entry(p, &br->port_list, list)
247 netdev_set_rx_headroom(p->dev, new_hr);
248
249 br->dev->needed_headroom = new_hr;
250}
251
252/* Delete port(interface) from bridge is done in two steps.
253 * via RCU. First step, marks device as down. That deletes
254 * all the timers and stops new packets from flowing through.
255 *
256 * Final cleanup doesn't occur until after all CPU's finished
257 * processing packets.
258 *
259 * Protected from multiple admin operations by RTNL mutex
260 */
261static void del_nbp(struct net_bridge_port *p)
262{
263 struct net_bridge *br = p->br;
264 struct net_device *dev = p->dev;
265
266 sysfs_remove_link(br->ifobj, p->dev->name);
267
268 nbp_delete_promisc(p);
269
270 spin_lock_bh(&br->lock);
271 br_stp_disable_port(p);
272 spin_unlock_bh(&br->lock);
273
274 br_ifinfo_notify(RTM_DELLINK, NULL, p);
275
276 list_del_rcu(&p->list);
277 if (netdev_get_fwd_headroom(dev) == br->dev->needed_headroom)
278 update_headroom(br, get_max_headroom(br));
279 netdev_reset_rx_headroom(dev);
280
281 nbp_vlan_flush(p);
282 br_fdb_delete_by_port(br, p, 0, 1);
283 switchdev_deferred_process();
284
285 nbp_update_port_count(br);
286
287 netdev_upper_dev_unlink(dev, br->dev);
288
289 dev->priv_flags &= ~IFF_BRIDGE_PORT;
290
291 netdev_rx_handler_unregister(dev);
292
293 br_multicast_del_port(p);
294
295 kobject_uevent(&p->kobj, KOBJ_REMOVE);
296 kobject_del(&p->kobj);
297
298 br_netpoll_disable(p);
299
300 call_rcu(&p->rcu, destroy_nbp_rcu);
301}
302
303/* Delete bridge device */
304void br_dev_delete(struct net_device *dev, struct list_head *head)
305{
306 struct net_bridge *br = netdev_priv(dev);
307 struct net_bridge_port *p, *n;
308
309 list_for_each_entry_safe(p, n, &br->port_list, list) {
310 del_nbp(p);
311 }
312
313 br_recalculate_neigh_suppress_enabled(br);
314
315 br_fdb_delete_by_port(br, NULL, 0, 1);
316
317 cancel_delayed_work_sync(&br->gc_work);
318
319 br_sysfs_delbr(br->dev);
320 unregister_netdevice_queue(br->dev, head);
321}
322
323/* find an available port number */
324static int find_portno(struct net_bridge *br)
325{
326 int index;
327 struct net_bridge_port *p;
328 unsigned long *inuse;
329
330 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
331 GFP_KERNEL);
332 if (!inuse)
333 return -ENOMEM;
334
335 set_bit(0, inuse); /* zero is reserved */
336 list_for_each_entry(p, &br->port_list, list) {
337 set_bit(p->port_no, inuse);
338 }
339 index = find_first_zero_bit(inuse, BR_MAX_PORTS);
340 kfree(inuse);
341
342 return (index >= BR_MAX_PORTS) ? -EXFULL : index;
343}
344
345/* called with RTNL but without bridge lock */
346static struct net_bridge_port *new_nbp(struct net_bridge *br,
347 struct net_device *dev)
348{
349 struct net_bridge_port *p;
350 int index, err;
351
352 index = find_portno(br);
353 if (index < 0)
354 return ERR_PTR(index);
355
356 p = kzalloc(sizeof(*p), GFP_KERNEL);
357 if (p == NULL)
358 return ERR_PTR(-ENOMEM);
359
360 p->br = br;
361 dev_hold(dev);
362 p->dev = dev;
363 p->path_cost = port_cost(dev);
364 p->priority = 0x8000 >> BR_PORT_BITS;
365 p->port_no = index;
366 p->flags = BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD | BR_BCAST_FLOOD;
367 br_init_port(p);
368 br_set_state(p, BR_STATE_DISABLED);
369 br_stp_port_timer_init(p);
370 err = br_multicast_add_port(p);
371 if (err) {
372 dev_put(dev);
373 kfree(p);
374 p = ERR_PTR(err);
375 }
376
377 return p;
378}
379
380int br_add_bridge(struct net *net, const char *name)
381{
382 struct net_device *dev;
383 int res;
384
385 dev = alloc_netdev(sizeof(struct net_bridge), name, NET_NAME_UNKNOWN,
386 br_dev_setup);
387
388 if (!dev)
389 return -ENOMEM;
390
391 dev_net_set(dev, net);
392 dev->rtnl_link_ops = &br_link_ops;
393
394 res = register_netdev(dev);
395 if (res)
396 free_netdev(dev);
397 return res;
398}
399
400int br_del_bridge(struct net *net, const char *name)
401{
402 struct net_device *dev;
403 int ret = 0;
404
405 rtnl_lock();
406 dev = __dev_get_by_name(net, name);
407 if (dev == NULL)
408 ret = -ENXIO; /* Could not find device */
409
410 else if (!(dev->priv_flags & IFF_EBRIDGE)) {
411 /* Attempt to delete non bridge device! */
412 ret = -EPERM;
413 }
414
415 else if (dev->flags & IFF_UP) {
416 /* Not shutdown yet. */
417 ret = -EBUSY;
418 }
419
420 else
421 br_dev_delete(dev, NULL);
422
423 rtnl_unlock();
424 return ret;
425}
426
427/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
428static int br_mtu_min(const struct net_bridge *br)
429{
430 const struct net_bridge_port *p;
431 int ret_mtu = 0;
432
433 list_for_each_entry(p, &br->port_list, list)
434 if (!ret_mtu || ret_mtu > p->dev->mtu)
435 ret_mtu = p->dev->mtu;
436
437 return ret_mtu ? ret_mtu : ETH_DATA_LEN;
438}
439
440void br_mtu_auto_adjust(struct net_bridge *br)
441{
442 ASSERT_RTNL();
443
444 /* if the bridge MTU was manually configured don't mess with it */
445 if (br->mtu_set_by_user)
446 return;
447
448 /* change to the minimum MTU and clear the flag which was set by
449 * the bridge ndo_change_mtu callback
450 */
451 dev_set_mtu(br->dev, br_mtu_min(br));
452 br->mtu_set_by_user = false;
453}
454
455static void br_set_gso_limits(struct net_bridge *br)
456{
457 unsigned int gso_max_size = GSO_MAX_SIZE;
458 u16 gso_max_segs = GSO_MAX_SEGS;
459 const struct net_bridge_port *p;
460
461 list_for_each_entry(p, &br->port_list, list) {
462 gso_max_size = min(gso_max_size, p->dev->gso_max_size);
463 gso_max_segs = min(gso_max_segs, p->dev->gso_max_segs);
464 }
465 br->dev->gso_max_size = gso_max_size;
466 br->dev->gso_max_segs = gso_max_segs;
467}
468
469/*
470 * Recomputes features using slave's features
471 */
472netdev_features_t br_features_recompute(struct net_bridge *br,
473 netdev_features_t features)
474{
475 struct net_bridge_port *p;
476 netdev_features_t mask;
477
478 if (list_empty(&br->port_list))
479 return features;
480
481 mask = features;
482 features &= ~NETIF_F_ONE_FOR_ALL;
483
484 list_for_each_entry(p, &br->port_list, list) {
485 features = netdev_increment_features(features,
486 p->dev->features, mask);
487 }
488 features = netdev_add_tso_features(features, mask);
489
490 return features;
491}
492
493/* called with RTNL */
494int br_add_if(struct net_bridge *br, struct net_device *dev,
495 struct netlink_ext_ack *extack)
496{
497 struct net_bridge_port *p;
498 int err = 0;
499 unsigned br_hr, dev_hr;
500 bool changed_addr;
501
502 /* Don't allow bridging non-ethernet like devices, or DSA-enabled
503 * master network devices since the bridge layer rx_handler prevents
504 * the DSA fake ethertype handler to be invoked, so we do not strip off
505 * the DSA switch tag protocol header and the bridge layer just return
506 * RX_HANDLER_CONSUMED, stopping RX processing for these frames.
507 */
508 if ((dev->flags & IFF_LOOPBACK) ||
509 dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN ||
510 !is_valid_ether_addr(dev->dev_addr) ||
511 netdev_uses_dsa(dev))
512 return -EINVAL;
513
514 /* No bridging of bridges */
515 if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit) {
516 NL_SET_ERR_MSG(extack,
517 "Can not enslave a bridge to a bridge");
518 return -ELOOP;
519 }
520
521 /* Device has master upper dev */
522 if (netdev_master_upper_dev_get(dev))
523 return -EBUSY;
524
525 /* No bridging devices that dislike that (e.g. wireless) */
526 if (dev->priv_flags & IFF_DONT_BRIDGE) {
527 NL_SET_ERR_MSG(extack,
528 "Device does not allow enslaving to a bridge");
529 return -EOPNOTSUPP;
530 }
531
532 p = new_nbp(br, dev);
533 if (IS_ERR(p))
534 return PTR_ERR(p);
535
536 call_netdevice_notifiers(NETDEV_JOIN, dev);
537
538 err = dev_set_allmulti(dev, 1);
539 if (err)
540 goto put_back;
541
542 err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
543 SYSFS_BRIDGE_PORT_ATTR);
544 if (err)
545 goto err1;
546
547 err = br_sysfs_addif(p);
548 if (err)
549 goto err2;
550
551 err = br_netpoll_enable(p);
552 if (err)
553 goto err3;
554
555 err = netdev_rx_handler_register(dev, br_handle_frame, p);
556 if (err)
557 goto err4;
558
559 dev->priv_flags |= IFF_BRIDGE_PORT;
560
561 err = netdev_master_upper_dev_link(dev, br->dev, NULL, NULL, extack);
562 if (err)
563 goto err5;
564
565 err = nbp_switchdev_mark_set(p);
566 if (err)
567 goto err6;
568
569 dev_disable_lro(dev);
570
571 list_add_rcu(&p->list, &br->port_list);
572
573 nbp_update_port_count(br);
574
575 netdev_update_features(br->dev);
576
577 br_hr = br->dev->needed_headroom;
578 dev_hr = netdev_get_fwd_headroom(dev);
579 if (br_hr < dev_hr)
580 update_headroom(br, dev_hr);
581 else
582 netdev_set_rx_headroom(dev, br_hr);
583
584 if (br_fdb_insert(br, p, dev->dev_addr, 0))
585 netdev_err(dev, "failed insert local address bridge forwarding table\n");
586
587 err = nbp_vlan_init(p);
588 if (err) {
589 netdev_err(dev, "failed to initialize vlan filtering on this port\n");
590 goto err7;
591 }
592
593 spin_lock_bh(&br->lock);
594 changed_addr = br_stp_recalculate_bridge_id(br);
595
596 if (netif_running(dev) && netif_oper_up(dev) &&
597 (br->dev->flags & IFF_UP))
598 br_stp_enable_port(p);
599 spin_unlock_bh(&br->lock);
600
601 br_ifinfo_notify(RTM_NEWLINK, NULL, p);
602
603 if (changed_addr)
604 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
605
606 br_mtu_auto_adjust(br);
607 br_set_gso_limits(br);
608
609 kobject_uevent(&p->kobj, KOBJ_ADD);
610
611 return 0;
612
613err7:
614 list_del_rcu(&p->list);
615 br_fdb_delete_by_port(br, p, 0, 1);
616 nbp_update_port_count(br);
617err6:
618 netdev_upper_dev_unlink(dev, br->dev);
619err5:
620 dev->priv_flags &= ~IFF_BRIDGE_PORT;
621 netdev_rx_handler_unregister(dev);
622err4:
623 br_netpoll_disable(p);
624err3:
625 sysfs_remove_link(br->ifobj, p->dev->name);
626err2:
627 kobject_put(&p->kobj);
628 p = NULL; /* kobject_put frees */
629err1:
630 dev_set_allmulti(dev, -1);
631put_back:
632 dev_put(dev);
633 kfree(p);
634 return err;
635}
636
637/* called with RTNL */
638int br_del_if(struct net_bridge *br, struct net_device *dev)
639{
640 struct net_bridge_port *p;
641 bool changed_addr;
642
643 p = br_port_get_rtnl(dev);
644 if (!p || p->br != br)
645 return -EINVAL;
646
647 /* Since more than one interface can be attached to a bridge,
648 * there still maybe an alternate path for netconsole to use;
649 * therefore there is no reason for a NETDEV_RELEASE event.
650 */
651 del_nbp(p);
652
653 br_mtu_auto_adjust(br);
654 br_set_gso_limits(br);
655
656 spin_lock_bh(&br->lock);
657 changed_addr = br_stp_recalculate_bridge_id(br);
658 spin_unlock_bh(&br->lock);
659
660 if (changed_addr)
661 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
662
663 netdev_update_features(br->dev);
664
665 return 0;
666}
667
668void br_port_flags_change(struct net_bridge_port *p, unsigned long mask)
669{
670 struct net_bridge *br = p->br;
671
672 if (mask & BR_AUTO_MASK)
673 nbp_update_port_count(br);
674
675 if (mask & BR_NEIGH_SUPPRESS)
676 br_recalculate_neigh_suppress_enabled(br);
677}