1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Device handling code |
4 | * Linux ethernet bridge |
5 | * |
6 | * Authors: |
7 | * Lennert Buytenhek <buytenh@gnu.org> |
8 | */ |
9 | |
10 | #include <linux/kernel.h> |
11 | #include <linux/netdevice.h> |
12 | #include <linux/netpoll.h> |
13 | #include <linux/etherdevice.h> |
14 | #include <linux/ethtool.h> |
15 | #include <linux/list.h> |
16 | #include <linux/netfilter_bridge.h> |
17 | |
18 | #include <linux/uaccess.h> |
19 | #include "br_private.h" |
20 | |
21 | #define COMMON_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | \ |
22 | NETIF_F_GSO_MASK | NETIF_F_HW_CSUM) |
23 | |
24 | const struct nf_br_ops __rcu *nf_br_ops __read_mostly; |
25 | EXPORT_SYMBOL_GPL(nf_br_ops); |
26 | |
27 | /* net device transmit always called with BH disabled */ |
28 | netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev) |
29 | { |
30 | struct net_bridge_mcast_port *pmctx_null = NULL; |
31 | struct net_bridge *br = netdev_priv(dev); |
32 | struct net_bridge_mcast *brmctx = &br->multicast_ctx; |
33 | struct net_bridge_fdb_entry *dst; |
34 | struct net_bridge_mdb_entry *mdst; |
35 | const struct nf_br_ops *nf_ops; |
36 | u8 state = BR_STATE_FORWARDING; |
37 | struct net_bridge_vlan *vlan; |
38 | const unsigned char *dest; |
39 | u16 vid = 0; |
40 | |
41 | memset(skb->cb, 0, sizeof(struct br_input_skb_cb)); |
42 | br_tc_skb_miss_set(skb, miss: false); |
43 | |
44 | rcu_read_lock(); |
45 | nf_ops = rcu_dereference(nf_br_ops); |
46 | if (nf_ops && nf_ops->br_dev_xmit_hook(skb)) { |
47 | rcu_read_unlock(); |
48 | return NETDEV_TX_OK; |
49 | } |
50 | |
51 | dev_sw_netstats_tx_add(dev, packets: 1, len: skb->len); |
52 | |
53 | br_switchdev_frame_unmark(skb); |
54 | BR_INPUT_SKB_CB(skb)->brdev = dev; |
55 | BR_INPUT_SKB_CB(skb)->frag_max_size = 0; |
56 | |
57 | skb_reset_mac_header(skb); |
58 | skb_pull(skb, ETH_HLEN); |
59 | |
60 | if (!br_allowed_ingress(br, vg: br_vlan_group_rcu(br), skb, vid: &vid, |
61 | state: &state, vlan: &vlan)) |
62 | goto out; |
63 | |
64 | if (IS_ENABLED(CONFIG_INET) && |
65 | (eth_hdr(skb)->h_proto == htons(ETH_P_ARP) || |
66 | eth_hdr(skb)->h_proto == htons(ETH_P_RARP)) && |
67 | br_opt_get(br, opt: BROPT_NEIGH_SUPPRESS_ENABLED)) { |
68 | br_do_proxy_suppress_arp(skb, br, vid, NULL); |
69 | } else if (IS_ENABLED(CONFIG_IPV6) && |
70 | skb->protocol == htons(ETH_P_IPV6) && |
71 | br_opt_get(br, opt: BROPT_NEIGH_SUPPRESS_ENABLED) && |
72 | pskb_may_pull(skb, len: sizeof(struct ipv6hdr) + |
73 | sizeof(struct nd_msg)) && |
74 | ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) { |
75 | struct nd_msg *msg, _msg; |
76 | |
77 | msg = br_is_nd_neigh_msg(skb, m: &_msg); |
78 | if (msg) |
79 | br_do_suppress_nd(skb, br, vid, NULL, msg); |
80 | } |
81 | |
82 | dest = eth_hdr(skb)->h_dest; |
83 | if (is_broadcast_ether_addr(addr: dest)) { |
84 | br_flood(br, skb, pkt_type: BR_PKT_BROADCAST, local_rcv: false, local_orig: true, vid); |
85 | } else if (is_multicast_ether_addr(addr: dest)) { |
86 | if (unlikely(netpoll_tx_running(dev))) { |
87 | br_flood(br, skb, pkt_type: BR_PKT_MULTICAST, local_rcv: false, local_orig: true, vid); |
88 | goto out; |
89 | } |
90 | if (br_multicast_rcv(brmctx: &brmctx, pmctx: &pmctx_null, vlan, skb, vid)) { |
91 | kfree_skb(skb); |
92 | goto out; |
93 | } |
94 | |
95 | mdst = br_mdb_entry_skb_get(brmctx, skb, vid); |
96 | if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) && |
97 | br_multicast_querier_exists(brmctx, eth: eth_hdr(skb), mdb: mdst)) |
98 | br_multicast_flood(mdst, skb, brmctx, local_rcv: false, local_orig: true); |
99 | else |
100 | br_flood(br, skb, pkt_type: BR_PKT_MULTICAST, local_rcv: false, local_orig: true, vid); |
101 | } else if ((dst = br_fdb_find_rcu(br, addr: dest, vid)) != NULL) { |
102 | br_forward(to: dst->dst, skb, local_rcv: false, local_orig: true); |
103 | } else { |
104 | br_flood(br, skb, pkt_type: BR_PKT_UNICAST, local_rcv: false, local_orig: true, vid); |
105 | } |
106 | out: |
107 | rcu_read_unlock(); |
108 | return NETDEV_TX_OK; |
109 | } |
110 | |
111 | static struct lock_class_key bridge_netdev_addr_lock_key; |
112 | |
113 | static void br_set_lockdep_class(struct net_device *dev) |
114 | { |
115 | lockdep_set_class(&dev->addr_list_lock, &bridge_netdev_addr_lock_key); |
116 | } |
117 | |
118 | static int br_dev_init(struct net_device *dev) |
119 | { |
120 | struct net_bridge *br = netdev_priv(dev); |
121 | int err; |
122 | |
123 | dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); |
124 | if (!dev->tstats) |
125 | return -ENOMEM; |
126 | |
127 | err = br_fdb_hash_init(br); |
128 | if (err) { |
129 | free_percpu(pdata: dev->tstats); |
130 | return err; |
131 | } |
132 | |
133 | err = br_mdb_hash_init(br); |
134 | if (err) { |
135 | free_percpu(pdata: dev->tstats); |
136 | br_fdb_hash_fini(br); |
137 | return err; |
138 | } |
139 | |
140 | err = br_vlan_init(br); |
141 | if (err) { |
142 | free_percpu(pdata: dev->tstats); |
143 | br_mdb_hash_fini(br); |
144 | br_fdb_hash_fini(br); |
145 | return err; |
146 | } |
147 | |
148 | err = br_multicast_init_stats(br); |
149 | if (err) { |
150 | free_percpu(pdata: dev->tstats); |
151 | br_vlan_flush(br); |
152 | br_mdb_hash_fini(br); |
153 | br_fdb_hash_fini(br); |
154 | } |
155 | |
156 | br_set_lockdep_class(dev); |
157 | return err; |
158 | } |
159 | |
160 | static void br_dev_uninit(struct net_device *dev) |
161 | { |
162 | struct net_bridge *br = netdev_priv(dev); |
163 | |
164 | br_multicast_dev_del(br); |
165 | br_multicast_uninit_stats(br); |
166 | br_vlan_flush(br); |
167 | br_mdb_hash_fini(br); |
168 | br_fdb_hash_fini(br); |
169 | free_percpu(pdata: dev->tstats); |
170 | } |
171 | |
172 | static int br_dev_open(struct net_device *dev) |
173 | { |
174 | struct net_bridge *br = netdev_priv(dev); |
175 | |
176 | netdev_update_features(dev); |
177 | netif_start_queue(dev); |
178 | br_stp_enable_bridge(br); |
179 | br_multicast_open(br); |
180 | |
181 | if (br_opt_get(br, opt: BROPT_MULTICAST_ENABLED)) |
182 | br_multicast_join_snoopers(br); |
183 | |
184 | return 0; |
185 | } |
186 | |
187 | static void br_dev_set_multicast_list(struct net_device *dev) |
188 | { |
189 | } |
190 | |
191 | static void br_dev_change_rx_flags(struct net_device *dev, int change) |
192 | { |
193 | if (change & IFF_PROMISC) |
194 | br_manage_promisc(br: netdev_priv(dev)); |
195 | } |
196 | |
197 | static int br_dev_stop(struct net_device *dev) |
198 | { |
199 | struct net_bridge *br = netdev_priv(dev); |
200 | |
201 | br_stp_disable_bridge(br); |
202 | br_multicast_stop(br); |
203 | |
204 | if (br_opt_get(br, opt: BROPT_MULTICAST_ENABLED)) |
205 | br_multicast_leave_snoopers(br); |
206 | |
207 | netif_stop_queue(dev); |
208 | |
209 | return 0; |
210 | } |
211 | |
212 | static int br_change_mtu(struct net_device *dev, int new_mtu) |
213 | { |
214 | struct net_bridge *br = netdev_priv(dev); |
215 | |
216 | dev->mtu = new_mtu; |
217 | |
218 | /* this flag will be cleared if the MTU was automatically adjusted */ |
219 | br_opt_toggle(br, opt: BROPT_MTU_SET_BY_USER, on: true); |
220 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
221 | /* remember the MTU in the rtable for PMTU */ |
222 | dst_metric_set(dst: &br->fake_rtable.dst, RTAX_MTU, val: new_mtu); |
223 | #endif |
224 | |
225 | return 0; |
226 | } |
227 | |
228 | /* Allow setting mac address to any valid ethernet address. */ |
229 | static int br_set_mac_address(struct net_device *dev, void *p) |
230 | { |
231 | struct net_bridge *br = netdev_priv(dev); |
232 | struct sockaddr *addr = p; |
233 | |
234 | if (!is_valid_ether_addr(addr: addr->sa_data)) |
235 | return -EADDRNOTAVAIL; |
236 | |
237 | /* dev_set_mac_addr() can be called by a master device on bridge's |
238 | * NETDEV_UNREGISTER, but since it's being destroyed do nothing |
239 | */ |
240 | if (dev->reg_state != NETREG_REGISTERED) |
241 | return -EBUSY; |
242 | |
243 | spin_lock_bh(lock: &br->lock); |
244 | if (!ether_addr_equal(addr1: dev->dev_addr, addr2: addr->sa_data)) { |
245 | /* Mac address will be changed in br_stp_change_bridge_id(). */ |
246 | br_stp_change_bridge_id(br, a: addr->sa_data); |
247 | } |
248 | spin_unlock_bh(lock: &br->lock); |
249 | |
250 | return 0; |
251 | } |
252 | |
253 | static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) |
254 | { |
255 | strscpy(p: info->driver, q: "bridge" , size: sizeof(info->driver)); |
256 | strscpy(p: info->version, BR_VERSION, size: sizeof(info->version)); |
257 | strscpy(p: info->fw_version, q: "N/A" , size: sizeof(info->fw_version)); |
258 | strscpy(p: info->bus_info, q: "N/A" , size: sizeof(info->bus_info)); |
259 | } |
260 | |
261 | static int br_get_link_ksettings(struct net_device *dev, |
262 | struct ethtool_link_ksettings *cmd) |
263 | { |
264 | struct net_bridge *br = netdev_priv(dev); |
265 | struct net_bridge_port *p; |
266 | |
267 | cmd->base.duplex = DUPLEX_UNKNOWN; |
268 | cmd->base.port = PORT_OTHER; |
269 | cmd->base.speed = SPEED_UNKNOWN; |
270 | |
271 | list_for_each_entry(p, &br->port_list, list) { |
272 | struct ethtool_link_ksettings ecmd; |
273 | struct net_device *pdev = p->dev; |
274 | |
275 | if (!netif_running(dev: pdev) || !netif_oper_up(dev: pdev)) |
276 | continue; |
277 | |
278 | if (__ethtool_get_link_ksettings(dev: pdev, link_ksettings: &ecmd)) |
279 | continue; |
280 | |
281 | if (ecmd.base.speed == (__u32)SPEED_UNKNOWN) |
282 | continue; |
283 | |
284 | if (cmd->base.speed == (__u32)SPEED_UNKNOWN || |
285 | cmd->base.speed < ecmd.base.speed) |
286 | cmd->base.speed = ecmd.base.speed; |
287 | } |
288 | |
289 | return 0; |
290 | } |
291 | |
292 | static netdev_features_t br_fix_features(struct net_device *dev, |
293 | netdev_features_t features) |
294 | { |
295 | struct net_bridge *br = netdev_priv(dev); |
296 | |
297 | return br_features_recompute(br, features); |
298 | } |
299 | |
300 | #ifdef CONFIG_NET_POLL_CONTROLLER |
301 | static void br_poll_controller(struct net_device *br_dev) |
302 | { |
303 | } |
304 | |
305 | static void br_netpoll_cleanup(struct net_device *dev) |
306 | { |
307 | struct net_bridge *br = netdev_priv(dev); |
308 | struct net_bridge_port *p; |
309 | |
310 | list_for_each_entry(p, &br->port_list, list) |
311 | br_netpoll_disable(p); |
312 | } |
313 | |
314 | static int __br_netpoll_enable(struct net_bridge_port *p) |
315 | { |
316 | struct netpoll *np; |
317 | int err; |
318 | |
319 | np = kzalloc(size: sizeof(*p->np), GFP_KERNEL); |
320 | if (!np) |
321 | return -ENOMEM; |
322 | |
323 | err = __netpoll_setup(np, ndev: p->dev); |
324 | if (err) { |
325 | kfree(objp: np); |
326 | return err; |
327 | } |
328 | |
329 | p->np = np; |
330 | return err; |
331 | } |
332 | |
333 | int br_netpoll_enable(struct net_bridge_port *p) |
334 | { |
335 | if (!p->br->dev->npinfo) |
336 | return 0; |
337 | |
338 | return __br_netpoll_enable(p); |
339 | } |
340 | |
341 | static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni) |
342 | { |
343 | struct net_bridge *br = netdev_priv(dev); |
344 | struct net_bridge_port *p; |
345 | int err = 0; |
346 | |
347 | list_for_each_entry(p, &br->port_list, list) { |
348 | if (!p->dev) |
349 | continue; |
350 | err = __br_netpoll_enable(p); |
351 | if (err) |
352 | goto fail; |
353 | } |
354 | |
355 | out: |
356 | return err; |
357 | |
358 | fail: |
359 | br_netpoll_cleanup(dev); |
360 | goto out; |
361 | } |
362 | |
363 | void br_netpoll_disable(struct net_bridge_port *p) |
364 | { |
365 | struct netpoll *np = p->np; |
366 | |
367 | if (!np) |
368 | return; |
369 | |
370 | p->np = NULL; |
371 | |
372 | __netpoll_free(np); |
373 | } |
374 | |
375 | #endif |
376 | |
377 | static int br_add_slave(struct net_device *dev, struct net_device *slave_dev, |
378 | struct netlink_ext_ack *extack) |
379 | |
380 | { |
381 | struct net_bridge *br = netdev_priv(dev); |
382 | |
383 | return br_add_if(br, dev: slave_dev, extack); |
384 | } |
385 | |
386 | static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) |
387 | { |
388 | struct net_bridge *br = netdev_priv(dev); |
389 | |
390 | return br_del_if(br, dev: slave_dev); |
391 | } |
392 | |
393 | static int br_fill_forward_path(struct net_device_path_ctx *ctx, |
394 | struct net_device_path *path) |
395 | { |
396 | struct net_bridge_fdb_entry *f; |
397 | struct net_bridge_port *dst; |
398 | struct net_bridge *br; |
399 | |
400 | if (netif_is_bridge_port(dev: ctx->dev)) |
401 | return -1; |
402 | |
403 | br = netdev_priv(dev: ctx->dev); |
404 | |
405 | br_vlan_fill_forward_path_pvid(br, ctx, path); |
406 | |
407 | f = br_fdb_find_rcu(br, addr: ctx->daddr, vid: path->bridge.vlan_id); |
408 | if (!f || !f->dst) |
409 | return -1; |
410 | |
411 | dst = READ_ONCE(f->dst); |
412 | if (!dst) |
413 | return -1; |
414 | |
415 | if (br_vlan_fill_forward_path_mode(br, dst, path)) |
416 | return -1; |
417 | |
418 | path->type = DEV_PATH_BRIDGE; |
419 | path->dev = dst->br->dev; |
420 | ctx->dev = dst->dev; |
421 | |
422 | switch (path->bridge.vlan_mode) { |
423 | case DEV_PATH_BR_VLAN_TAG: |
424 | if (ctx->num_vlans >= ARRAY_SIZE(ctx->vlan)) |
425 | return -ENOSPC; |
426 | ctx->vlan[ctx->num_vlans].id = path->bridge.vlan_id; |
427 | ctx->vlan[ctx->num_vlans].proto = path->bridge.vlan_proto; |
428 | ctx->num_vlans++; |
429 | break; |
430 | case DEV_PATH_BR_VLAN_UNTAG_HW: |
431 | case DEV_PATH_BR_VLAN_UNTAG: |
432 | ctx->num_vlans--; |
433 | break; |
434 | case DEV_PATH_BR_VLAN_KEEP: |
435 | break; |
436 | } |
437 | |
438 | return 0; |
439 | } |
440 | |
441 | static const struct ethtool_ops br_ethtool_ops = { |
442 | .get_drvinfo = br_getinfo, |
443 | .get_link = ethtool_op_get_link, |
444 | .get_link_ksettings = br_get_link_ksettings, |
445 | }; |
446 | |
447 | static const struct net_device_ops br_netdev_ops = { |
448 | .ndo_open = br_dev_open, |
449 | .ndo_stop = br_dev_stop, |
450 | .ndo_init = br_dev_init, |
451 | .ndo_uninit = br_dev_uninit, |
452 | .ndo_start_xmit = br_dev_xmit, |
453 | .ndo_get_stats64 = dev_get_tstats64, |
454 | .ndo_set_mac_address = br_set_mac_address, |
455 | .ndo_set_rx_mode = br_dev_set_multicast_list, |
456 | .ndo_change_rx_flags = br_dev_change_rx_flags, |
457 | .ndo_change_mtu = br_change_mtu, |
458 | .ndo_siocdevprivate = br_dev_siocdevprivate, |
459 | #ifdef CONFIG_NET_POLL_CONTROLLER |
460 | .ndo_netpoll_setup = br_netpoll_setup, |
461 | .ndo_netpoll_cleanup = br_netpoll_cleanup, |
462 | .ndo_poll_controller = br_poll_controller, |
463 | #endif |
464 | .ndo_add_slave = br_add_slave, |
465 | .ndo_del_slave = br_del_slave, |
466 | .ndo_fix_features = br_fix_features, |
467 | .ndo_fdb_add = br_fdb_add, |
468 | .ndo_fdb_del = br_fdb_delete, |
469 | .ndo_fdb_del_bulk = br_fdb_delete_bulk, |
470 | .ndo_fdb_dump = br_fdb_dump, |
471 | .ndo_fdb_get = br_fdb_get, |
472 | .ndo_mdb_add = br_mdb_add, |
473 | .ndo_mdb_del = br_mdb_del, |
474 | .ndo_mdb_dump = br_mdb_dump, |
475 | .ndo_mdb_get = br_mdb_get, |
476 | .ndo_bridge_getlink = br_getlink, |
477 | .ndo_bridge_setlink = br_setlink, |
478 | .ndo_bridge_dellink = br_dellink, |
479 | .ndo_features_check = passthru_features_check, |
480 | .ndo_fill_forward_path = br_fill_forward_path, |
481 | }; |
482 | |
483 | static struct device_type br_type = { |
484 | .name = "bridge" , |
485 | }; |
486 | |
487 | void br_dev_setup(struct net_device *dev) |
488 | { |
489 | struct net_bridge *br = netdev_priv(dev); |
490 | |
491 | eth_hw_addr_random(dev); |
492 | ether_setup(dev); |
493 | |
494 | dev->netdev_ops = &br_netdev_ops; |
495 | dev->needs_free_netdev = true; |
496 | dev->ethtool_ops = &br_ethtool_ops; |
497 | SET_NETDEV_DEVTYPE(dev, &br_type); |
498 | dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE; |
499 | |
500 | dev->features = COMMON_FEATURES | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL | |
501 | NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX; |
502 | dev->hw_features = COMMON_FEATURES | NETIF_F_HW_VLAN_CTAG_TX | |
503 | NETIF_F_HW_VLAN_STAG_TX; |
504 | dev->vlan_features = COMMON_FEATURES; |
505 | |
506 | br->dev = dev; |
507 | spin_lock_init(&br->lock); |
508 | INIT_LIST_HEAD(list: &br->port_list); |
509 | INIT_HLIST_HEAD(&br->fdb_list); |
510 | INIT_HLIST_HEAD(&br->frame_type_list); |
511 | #if IS_ENABLED(CONFIG_BRIDGE_MRP) |
512 | INIT_HLIST_HEAD(&br->mrp_list); |
513 | #endif |
514 | #if IS_ENABLED(CONFIG_BRIDGE_CFM) |
515 | INIT_HLIST_HEAD(&br->mep_list); |
516 | #endif |
517 | spin_lock_init(&br->hash_lock); |
518 | |
519 | br->bridge_id.prio[0] = 0x80; |
520 | br->bridge_id.prio[1] = 0x00; |
521 | |
522 | ether_addr_copy(dst: br->group_addr, eth_stp_addr); |
523 | |
524 | br->stp_enabled = BR_NO_STP; |
525 | br->group_fwd_mask = BR_GROUPFWD_DEFAULT; |
526 | br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT; |
527 | |
528 | br->designated_root = br->bridge_id; |
529 | br->bridge_max_age = br->max_age = 20 * HZ; |
530 | br->bridge_hello_time = br->hello_time = 2 * HZ; |
531 | br->bridge_forward_delay = br->forward_delay = 15 * HZ; |
532 | br->bridge_ageing_time = br->ageing_time = BR_DEFAULT_AGEING_TIME; |
533 | dev->max_mtu = ETH_MAX_MTU; |
534 | |
535 | br_netfilter_rtable_init(br); |
536 | br_stp_timer_init(br); |
537 | br_multicast_init(br); |
538 | INIT_DELAYED_WORK(&br->gc_work, br_fdb_cleanup); |
539 | } |
540 | |