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 int br_dev_init(struct net_device *dev) |
112 | { |
113 | struct net_bridge *br = netdev_priv(dev); |
114 | int err; |
115 | |
116 | err = br_fdb_hash_init(br); |
117 | if (err) |
118 | return err; |
119 | |
120 | err = br_mdb_hash_init(br); |
121 | if (err) { |
122 | br_fdb_hash_fini(br); |
123 | return err; |
124 | } |
125 | |
126 | err = br_vlan_init(br); |
127 | if (err) { |
128 | br_mdb_hash_fini(br); |
129 | br_fdb_hash_fini(br); |
130 | return err; |
131 | } |
132 | |
133 | err = br_multicast_init_stats(br); |
134 | if (err) { |
135 | br_vlan_flush(br); |
136 | br_mdb_hash_fini(br); |
137 | br_fdb_hash_fini(br); |
138 | return err; |
139 | } |
140 | |
141 | netdev_lockdep_set_classes(dev); |
142 | return 0; |
143 | } |
144 | |
145 | static void br_dev_uninit(struct net_device *dev) |
146 | { |
147 | struct net_bridge *br = netdev_priv(dev); |
148 | |
149 | br_multicast_dev_del(br); |
150 | br_multicast_uninit_stats(br); |
151 | br_vlan_flush(br); |
152 | br_mdb_hash_fini(br); |
153 | br_fdb_hash_fini(br); |
154 | } |
155 | |
156 | static int br_dev_open(struct net_device *dev) |
157 | { |
158 | struct net_bridge *br = netdev_priv(dev); |
159 | |
160 | netdev_update_features(dev); |
161 | netif_start_queue(dev); |
162 | br_stp_enable_bridge(br); |
163 | br_multicast_open(br); |
164 | |
165 | if (br_opt_get(br, opt: BROPT_MULTICAST_ENABLED)) |
166 | br_multicast_join_snoopers(br); |
167 | |
168 | return 0; |
169 | } |
170 | |
171 | static void br_dev_set_multicast_list(struct net_device *dev) |
172 | { |
173 | } |
174 | |
175 | static void br_dev_change_rx_flags(struct net_device *dev, int change) |
176 | { |
177 | if (change & IFF_PROMISC) |
178 | br_manage_promisc(br: netdev_priv(dev)); |
179 | } |
180 | |
181 | static int br_dev_stop(struct net_device *dev) |
182 | { |
183 | struct net_bridge *br = netdev_priv(dev); |
184 | |
185 | br_stp_disable_bridge(br); |
186 | br_multicast_stop(br); |
187 | |
188 | if (br_opt_get(br, opt: BROPT_MULTICAST_ENABLED)) |
189 | br_multicast_leave_snoopers(br); |
190 | |
191 | netif_stop_queue(dev); |
192 | |
193 | return 0; |
194 | } |
195 | |
196 | static int br_change_mtu(struct net_device *dev, int new_mtu) |
197 | { |
198 | struct net_bridge *br = netdev_priv(dev); |
199 | |
200 | dev->mtu = new_mtu; |
201 | |
202 | /* this flag will be cleared if the MTU was automatically adjusted */ |
203 | br_opt_toggle(br, opt: BROPT_MTU_SET_BY_USER, on: true); |
204 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
205 | /* remember the MTU in the rtable for PMTU */ |
206 | dst_metric_set(dst: &br->fake_rtable.dst, RTAX_MTU, val: new_mtu); |
207 | #endif |
208 | |
209 | return 0; |
210 | } |
211 | |
212 | /* Allow setting mac address to any valid ethernet address. */ |
213 | static int br_set_mac_address(struct net_device *dev, void *p) |
214 | { |
215 | struct net_bridge *br = netdev_priv(dev); |
216 | struct sockaddr *addr = p; |
217 | |
218 | if (!is_valid_ether_addr(addr: addr->sa_data)) |
219 | return -EADDRNOTAVAIL; |
220 | |
221 | /* dev_set_mac_addr() can be called by a master device on bridge's |
222 | * NETDEV_UNREGISTER, but since it's being destroyed do nothing |
223 | */ |
224 | if (dev->reg_state != NETREG_REGISTERED) |
225 | return -EBUSY; |
226 | |
227 | spin_lock_bh(lock: &br->lock); |
228 | if (!ether_addr_equal(addr1: dev->dev_addr, addr2: addr->sa_data)) { |
229 | /* Mac address will be changed in br_stp_change_bridge_id(). */ |
230 | br_stp_change_bridge_id(br, a: addr->sa_data); |
231 | } |
232 | spin_unlock_bh(lock: &br->lock); |
233 | |
234 | return 0; |
235 | } |
236 | |
237 | static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) |
238 | { |
239 | strscpy(info->driver, "bridge" , sizeof(info->driver)); |
240 | strscpy(info->version, BR_VERSION, sizeof(info->version)); |
241 | strscpy(info->fw_version, "N/A" , sizeof(info->fw_version)); |
242 | strscpy(info->bus_info, "N/A" , sizeof(info->bus_info)); |
243 | } |
244 | |
245 | static int br_get_link_ksettings(struct net_device *dev, |
246 | struct ethtool_link_ksettings *cmd) |
247 | { |
248 | struct net_bridge *br = netdev_priv(dev); |
249 | struct net_bridge_port *p; |
250 | |
251 | cmd->base.duplex = DUPLEX_UNKNOWN; |
252 | cmd->base.port = PORT_OTHER; |
253 | cmd->base.speed = SPEED_UNKNOWN; |
254 | |
255 | list_for_each_entry(p, &br->port_list, list) { |
256 | struct ethtool_link_ksettings ecmd; |
257 | struct net_device *pdev = p->dev; |
258 | |
259 | if (!netif_running(dev: pdev) || !netif_oper_up(dev: pdev)) |
260 | continue; |
261 | |
262 | if (__ethtool_get_link_ksettings(dev: pdev, link_ksettings: &ecmd)) |
263 | continue; |
264 | |
265 | if (ecmd.base.speed == (__u32)SPEED_UNKNOWN) |
266 | continue; |
267 | |
268 | if (cmd->base.speed == (__u32)SPEED_UNKNOWN || |
269 | cmd->base.speed < ecmd.base.speed) |
270 | cmd->base.speed = ecmd.base.speed; |
271 | } |
272 | |
273 | return 0; |
274 | } |
275 | |
276 | static netdev_features_t br_fix_features(struct net_device *dev, |
277 | netdev_features_t features) |
278 | { |
279 | struct net_bridge *br = netdev_priv(dev); |
280 | |
281 | return br_features_recompute(br, features); |
282 | } |
283 | |
284 | #ifdef CONFIG_NET_POLL_CONTROLLER |
285 | static void br_poll_controller(struct net_device *br_dev) |
286 | { |
287 | } |
288 | |
289 | static void br_netpoll_cleanup(struct net_device *dev) |
290 | { |
291 | struct net_bridge *br = netdev_priv(dev); |
292 | struct net_bridge_port *p; |
293 | |
294 | list_for_each_entry(p, &br->port_list, list) |
295 | br_netpoll_disable(p); |
296 | } |
297 | |
298 | static int __br_netpoll_enable(struct net_bridge_port *p) |
299 | { |
300 | struct netpoll *np; |
301 | int err; |
302 | |
303 | np = kzalloc(size: sizeof(*p->np), GFP_KERNEL); |
304 | if (!np) |
305 | return -ENOMEM; |
306 | |
307 | err = __netpoll_setup(np, ndev: p->dev); |
308 | if (err) { |
309 | kfree(objp: np); |
310 | return err; |
311 | } |
312 | |
313 | p->np = np; |
314 | return err; |
315 | } |
316 | |
317 | int br_netpoll_enable(struct net_bridge_port *p) |
318 | { |
319 | if (!p->br->dev->npinfo) |
320 | return 0; |
321 | |
322 | return __br_netpoll_enable(p); |
323 | } |
324 | |
325 | static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni) |
326 | { |
327 | struct net_bridge *br = netdev_priv(dev); |
328 | struct net_bridge_port *p; |
329 | int err = 0; |
330 | |
331 | list_for_each_entry(p, &br->port_list, list) { |
332 | if (!p->dev) |
333 | continue; |
334 | err = __br_netpoll_enable(p); |
335 | if (err) |
336 | goto fail; |
337 | } |
338 | |
339 | out: |
340 | return err; |
341 | |
342 | fail: |
343 | br_netpoll_cleanup(dev); |
344 | goto out; |
345 | } |
346 | |
347 | void br_netpoll_disable(struct net_bridge_port *p) |
348 | { |
349 | struct netpoll *np = p->np; |
350 | |
351 | if (!np) |
352 | return; |
353 | |
354 | p->np = NULL; |
355 | |
356 | __netpoll_free(np); |
357 | } |
358 | |
359 | #endif |
360 | |
361 | static int br_add_slave(struct net_device *dev, struct net_device *slave_dev, |
362 | struct netlink_ext_ack *extack) |
363 | |
364 | { |
365 | struct net_bridge *br = netdev_priv(dev); |
366 | |
367 | return br_add_if(br, dev: slave_dev, extack); |
368 | } |
369 | |
370 | static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) |
371 | { |
372 | struct net_bridge *br = netdev_priv(dev); |
373 | |
374 | return br_del_if(br, dev: slave_dev); |
375 | } |
376 | |
377 | static int br_fill_forward_path(struct net_device_path_ctx *ctx, |
378 | struct net_device_path *path) |
379 | { |
380 | struct net_bridge_fdb_entry *f; |
381 | struct net_bridge_port *dst; |
382 | struct net_bridge *br; |
383 | |
384 | if (netif_is_bridge_port(dev: ctx->dev)) |
385 | return -1; |
386 | |
387 | br = netdev_priv(dev: ctx->dev); |
388 | |
389 | br_vlan_fill_forward_path_pvid(br, ctx, path); |
390 | |
391 | f = br_fdb_find_rcu(br, addr: ctx->daddr, vid: path->bridge.vlan_id); |
392 | if (!f || !f->dst) |
393 | return -1; |
394 | |
395 | dst = READ_ONCE(f->dst); |
396 | if (!dst) |
397 | return -1; |
398 | |
399 | if (br_vlan_fill_forward_path_mode(br, dst, path)) |
400 | return -1; |
401 | |
402 | path->type = DEV_PATH_BRIDGE; |
403 | path->dev = dst->br->dev; |
404 | ctx->dev = dst->dev; |
405 | |
406 | switch (path->bridge.vlan_mode) { |
407 | case DEV_PATH_BR_VLAN_TAG: |
408 | if (ctx->num_vlans >= ARRAY_SIZE(ctx->vlan)) |
409 | return -ENOSPC; |
410 | ctx->vlan[ctx->num_vlans].id = path->bridge.vlan_id; |
411 | ctx->vlan[ctx->num_vlans].proto = path->bridge.vlan_proto; |
412 | ctx->num_vlans++; |
413 | break; |
414 | case DEV_PATH_BR_VLAN_UNTAG_HW: |
415 | case DEV_PATH_BR_VLAN_UNTAG: |
416 | ctx->num_vlans--; |
417 | break; |
418 | case DEV_PATH_BR_VLAN_KEEP: |
419 | break; |
420 | } |
421 | |
422 | return 0; |
423 | } |
424 | |
425 | static const struct ethtool_ops br_ethtool_ops = { |
426 | .get_drvinfo = br_getinfo, |
427 | .get_link = ethtool_op_get_link, |
428 | .get_link_ksettings = br_get_link_ksettings, |
429 | }; |
430 | |
431 | static const struct net_device_ops br_netdev_ops = { |
432 | .ndo_open = br_dev_open, |
433 | .ndo_stop = br_dev_stop, |
434 | .ndo_init = br_dev_init, |
435 | .ndo_uninit = br_dev_uninit, |
436 | .ndo_start_xmit = br_dev_xmit, |
437 | .ndo_get_stats64 = dev_get_tstats64, |
438 | .ndo_set_mac_address = br_set_mac_address, |
439 | .ndo_set_rx_mode = br_dev_set_multicast_list, |
440 | .ndo_change_rx_flags = br_dev_change_rx_flags, |
441 | .ndo_change_mtu = br_change_mtu, |
442 | .ndo_siocdevprivate = br_dev_siocdevprivate, |
443 | #ifdef CONFIG_NET_POLL_CONTROLLER |
444 | .ndo_netpoll_setup = br_netpoll_setup, |
445 | .ndo_netpoll_cleanup = br_netpoll_cleanup, |
446 | .ndo_poll_controller = br_poll_controller, |
447 | #endif |
448 | .ndo_add_slave = br_add_slave, |
449 | .ndo_del_slave = br_del_slave, |
450 | .ndo_fix_features = br_fix_features, |
451 | .ndo_fdb_add = br_fdb_add, |
452 | .ndo_fdb_del = br_fdb_delete, |
453 | .ndo_fdb_del_bulk = br_fdb_delete_bulk, |
454 | .ndo_fdb_dump = br_fdb_dump, |
455 | .ndo_fdb_get = br_fdb_get, |
456 | .ndo_mdb_add = br_mdb_add, |
457 | .ndo_mdb_del = br_mdb_del, |
458 | .ndo_mdb_del_bulk = br_mdb_del_bulk, |
459 | .ndo_mdb_dump = br_mdb_dump, |
460 | .ndo_mdb_get = br_mdb_get, |
461 | .ndo_bridge_getlink = br_getlink, |
462 | .ndo_bridge_setlink = br_setlink, |
463 | .ndo_bridge_dellink = br_dellink, |
464 | .ndo_features_check = passthru_features_check, |
465 | .ndo_fill_forward_path = br_fill_forward_path, |
466 | }; |
467 | |
468 | static const struct device_type br_type = { |
469 | .name = "bridge" , |
470 | }; |
471 | |
472 | void br_dev_setup(struct net_device *dev) |
473 | { |
474 | struct net_bridge *br = netdev_priv(dev); |
475 | |
476 | eth_hw_addr_random(dev); |
477 | ether_setup(dev); |
478 | |
479 | dev->netdev_ops = &br_netdev_ops; |
480 | dev->needs_free_netdev = true; |
481 | dev->ethtool_ops = &br_ethtool_ops; |
482 | SET_NETDEV_DEVTYPE(dev, &br_type); |
483 | dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE; |
484 | |
485 | dev->features = COMMON_FEATURES | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL | |
486 | NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX; |
487 | dev->hw_features = COMMON_FEATURES | NETIF_F_HW_VLAN_CTAG_TX | |
488 | NETIF_F_HW_VLAN_STAG_TX; |
489 | dev->vlan_features = COMMON_FEATURES; |
490 | dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; |
491 | |
492 | br->dev = dev; |
493 | spin_lock_init(&br->lock); |
494 | INIT_LIST_HEAD(list: &br->port_list); |
495 | INIT_HLIST_HEAD(&br->fdb_list); |
496 | INIT_HLIST_HEAD(&br->frame_type_list); |
497 | #if IS_ENABLED(CONFIG_BRIDGE_MRP) |
498 | INIT_HLIST_HEAD(&br->mrp_list); |
499 | #endif |
500 | #if IS_ENABLED(CONFIG_BRIDGE_CFM) |
501 | INIT_HLIST_HEAD(&br->mep_list); |
502 | #endif |
503 | spin_lock_init(&br->hash_lock); |
504 | |
505 | br->bridge_id.prio[0] = 0x80; |
506 | br->bridge_id.prio[1] = 0x00; |
507 | |
508 | ether_addr_copy(dst: br->group_addr, eth_stp_addr); |
509 | |
510 | br->stp_enabled = BR_NO_STP; |
511 | br->group_fwd_mask = BR_GROUPFWD_DEFAULT; |
512 | br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT; |
513 | |
514 | br->designated_root = br->bridge_id; |
515 | br->bridge_max_age = br->max_age = 20 * HZ; |
516 | br->bridge_hello_time = br->hello_time = 2 * HZ; |
517 | br->bridge_forward_delay = br->forward_delay = 15 * HZ; |
518 | br->bridge_ageing_time = br->ageing_time = BR_DEFAULT_AGEING_TIME; |
519 | dev->max_mtu = ETH_MAX_MTU; |
520 | |
521 | br_netfilter_rtable_init(br); |
522 | br_stp_timer_init(br); |
523 | br_multicast_init(br); |
524 | INIT_DELAYED_WORK(&br->gc_work, br_fdb_cleanup); |
525 | } |
526 | |