1 // SPDX-License-Identifier: GPL-2.0-or-later
4 * Linux ethernet bridge
7 * Lennert Buytenhek <buytenh@gnu.org>
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>
18 #include <linux/uaccess.h>
19 #include "br_private.h"
21 #define COMMON_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | \
22 NETIF_F_GSO_MASK | NETIF_F_HW_CSUM)
24 const struct nf_br_ops __rcu *nf_br_ops __read_mostly;
25 EXPORT_SYMBOL_GPL(nf_br_ops);
27 /* net device transmit always called with BH disabled */
28 netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
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;
41 memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
42 br_tc_skb_miss_set(skb, false);
45 nf_ops = rcu_dereference(nf_br_ops);
46 if (nf_ops && nf_ops->br_dev_xmit_hook(skb)) {
51 dev_sw_netstats_tx_add(dev, 1, skb->len);
53 br_switchdev_frame_unmark(skb);
54 BR_INPUT_SKB_CB(skb)->brdev = dev;
55 BR_INPUT_SKB_CB(skb)->frag_max_size = 0;
57 skb_reset_mac_header(skb);
58 skb_pull(skb, ETH_HLEN);
60 if (!br_allowed_ingress(br, br_vlan_group_rcu(br), skb, &vid,
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, 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, BROPT_NEIGH_SUPPRESS_ENABLED) &&
72 pskb_may_pull(skb, sizeof(struct ipv6hdr) +
73 sizeof(struct nd_msg)) &&
74 ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) {
75 struct nd_msg *msg, _msg;
77 msg = br_is_nd_neigh_msg(skb, &_msg);
79 br_do_suppress_nd(skb, br, vid, NULL, msg);
82 dest = eth_hdr(skb)->h_dest;
83 if (is_broadcast_ether_addr(dest)) {
84 br_flood(br, skb, BR_PKT_BROADCAST, false, true, vid);
85 } else if (is_multicast_ether_addr(dest)) {
86 if (unlikely(netpoll_tx_running(dev))) {
87 br_flood(br, skb, BR_PKT_MULTICAST, false, true, vid);
90 if (br_multicast_rcv(&brmctx, &pmctx_null, vlan, skb, vid)) {
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_hdr(skb), mdst))
98 br_multicast_flood(mdst, skb, brmctx, false, true);
100 br_flood(br, skb, BR_PKT_MULTICAST, false, true, vid);
101 } else if ((dst = br_fdb_find_rcu(br, dest, vid)) != NULL) {
102 br_forward(dst->dst, skb, false, true);
104 br_flood(br, skb, BR_PKT_UNICAST, false, true, vid);
111 static int br_dev_init(struct net_device *dev)
113 struct net_bridge *br = netdev_priv(dev);
116 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
120 err = br_fdb_hash_init(br);
122 free_percpu(dev->tstats);
126 err = br_mdb_hash_init(br);
128 free_percpu(dev->tstats);
129 br_fdb_hash_fini(br);
133 err = br_vlan_init(br);
135 free_percpu(dev->tstats);
136 br_mdb_hash_fini(br);
137 br_fdb_hash_fini(br);
141 err = br_multicast_init_stats(br);
143 free_percpu(dev->tstats);
145 br_mdb_hash_fini(br);
146 br_fdb_hash_fini(br);
149 netdev_lockdep_set_classes(dev);
153 static void br_dev_uninit(struct net_device *dev)
155 struct net_bridge *br = netdev_priv(dev);
157 br_multicast_dev_del(br);
158 br_multicast_uninit_stats(br);
160 br_mdb_hash_fini(br);
161 br_fdb_hash_fini(br);
162 free_percpu(dev->tstats);
165 static int br_dev_open(struct net_device *dev)
167 struct net_bridge *br = netdev_priv(dev);
169 netdev_update_features(dev);
170 netif_start_queue(dev);
171 br_stp_enable_bridge(br);
172 br_multicast_open(br);
174 if (br_opt_get(br, BROPT_MULTICAST_ENABLED))
175 br_multicast_join_snoopers(br);
180 static void br_dev_set_multicast_list(struct net_device *dev)
184 static void br_dev_change_rx_flags(struct net_device *dev, int change)
186 if (change & IFF_PROMISC)
187 br_manage_promisc(netdev_priv(dev));
190 static int br_dev_stop(struct net_device *dev)
192 struct net_bridge *br = netdev_priv(dev);
194 br_stp_disable_bridge(br);
195 br_multicast_stop(br);
197 if (br_opt_get(br, BROPT_MULTICAST_ENABLED))
198 br_multicast_leave_snoopers(br);
200 netif_stop_queue(dev);
205 static int br_change_mtu(struct net_device *dev, int new_mtu)
207 struct net_bridge *br = netdev_priv(dev);
211 /* this flag will be cleared if the MTU was automatically adjusted */
212 br_opt_toggle(br, BROPT_MTU_SET_BY_USER, true);
213 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
214 /* remember the MTU in the rtable for PMTU */
215 dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu);
221 /* Allow setting mac address to any valid ethernet address. */
222 static int br_set_mac_address(struct net_device *dev, void *p)
224 struct net_bridge *br = netdev_priv(dev);
225 struct sockaddr *addr = p;
227 if (!is_valid_ether_addr(addr->sa_data))
228 return -EADDRNOTAVAIL;
230 /* dev_set_mac_addr() can be called by a master device on bridge's
231 * NETDEV_UNREGISTER, but since it's being destroyed do nothing
233 if (dev->reg_state != NETREG_REGISTERED)
236 spin_lock_bh(&br->lock);
237 if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) {
238 /* Mac address will be changed in br_stp_change_bridge_id(). */
239 br_stp_change_bridge_id(br, addr->sa_data);
241 spin_unlock_bh(&br->lock);
246 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
248 strscpy(info->driver, "bridge", sizeof(info->driver));
249 strscpy(info->version, BR_VERSION, sizeof(info->version));
250 strscpy(info->fw_version, "N/A", sizeof(info->fw_version));
251 strscpy(info->bus_info, "N/A", sizeof(info->bus_info));
254 static int br_get_link_ksettings(struct net_device *dev,
255 struct ethtool_link_ksettings *cmd)
257 struct net_bridge *br = netdev_priv(dev);
258 struct net_bridge_port *p;
260 cmd->base.duplex = DUPLEX_UNKNOWN;
261 cmd->base.port = PORT_OTHER;
262 cmd->base.speed = SPEED_UNKNOWN;
264 list_for_each_entry(p, &br->port_list, list) {
265 struct ethtool_link_ksettings ecmd;
266 struct net_device *pdev = p->dev;
268 if (!netif_running(pdev) || !netif_oper_up(pdev))
271 if (__ethtool_get_link_ksettings(pdev, &ecmd))
274 if (ecmd.base.speed == (__u32)SPEED_UNKNOWN)
277 if (cmd->base.speed == (__u32)SPEED_UNKNOWN ||
278 cmd->base.speed < ecmd.base.speed)
279 cmd->base.speed = ecmd.base.speed;
285 static netdev_features_t br_fix_features(struct net_device *dev,
286 netdev_features_t features)
288 struct net_bridge *br = netdev_priv(dev);
290 return br_features_recompute(br, features);
293 #ifdef CONFIG_NET_POLL_CONTROLLER
294 static void br_poll_controller(struct net_device *br_dev)
298 static void br_netpoll_cleanup(struct net_device *dev)
300 struct net_bridge *br = netdev_priv(dev);
301 struct net_bridge_port *p;
303 list_for_each_entry(p, &br->port_list, list)
304 br_netpoll_disable(p);
307 static int __br_netpoll_enable(struct net_bridge_port *p)
312 np = kzalloc(sizeof(*p->np), GFP_KERNEL);
316 err = __netpoll_setup(np, p->dev);
326 int br_netpoll_enable(struct net_bridge_port *p)
328 if (!p->br->dev->npinfo)
331 return __br_netpoll_enable(p);
334 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
336 struct net_bridge *br = netdev_priv(dev);
337 struct net_bridge_port *p;
340 list_for_each_entry(p, &br->port_list, list) {
343 err = __br_netpoll_enable(p);
352 br_netpoll_cleanup(dev);
356 void br_netpoll_disable(struct net_bridge_port *p)
358 struct netpoll *np = p->np;
370 static int br_add_slave(struct net_device *dev, struct net_device *slave_dev,
371 struct netlink_ext_ack *extack)
374 struct net_bridge *br = netdev_priv(dev);
376 return br_add_if(br, slave_dev, extack);
379 static int br_del_slave(struct net_device *dev, struct net_device *slave_dev)
381 struct net_bridge *br = netdev_priv(dev);
383 return br_del_if(br, slave_dev);
386 static int br_fill_forward_path(struct net_device_path_ctx *ctx,
387 struct net_device_path *path)
389 struct net_bridge_fdb_entry *f;
390 struct net_bridge_port *dst;
391 struct net_bridge *br;
393 if (netif_is_bridge_port(ctx->dev))
396 br = netdev_priv(ctx->dev);
398 br_vlan_fill_forward_path_pvid(br, ctx, path);
400 f = br_fdb_find_rcu(br, ctx->daddr, path->bridge.vlan_id);
404 dst = READ_ONCE(f->dst);
408 if (br_vlan_fill_forward_path_mode(br, dst, path))
411 path->type = DEV_PATH_BRIDGE;
412 path->dev = dst->br->dev;
415 switch (path->bridge.vlan_mode) {
416 case DEV_PATH_BR_VLAN_TAG:
417 if (ctx->num_vlans >= ARRAY_SIZE(ctx->vlan))
419 ctx->vlan[ctx->num_vlans].id = path->bridge.vlan_id;
420 ctx->vlan[ctx->num_vlans].proto = path->bridge.vlan_proto;
423 case DEV_PATH_BR_VLAN_UNTAG_HW:
424 case DEV_PATH_BR_VLAN_UNTAG:
427 case DEV_PATH_BR_VLAN_KEEP:
434 static const struct ethtool_ops br_ethtool_ops = {
435 .get_drvinfo = br_getinfo,
436 .get_link = ethtool_op_get_link,
437 .get_link_ksettings = br_get_link_ksettings,
440 static const struct net_device_ops br_netdev_ops = {
441 .ndo_open = br_dev_open,
442 .ndo_stop = br_dev_stop,
443 .ndo_init = br_dev_init,
444 .ndo_uninit = br_dev_uninit,
445 .ndo_start_xmit = br_dev_xmit,
446 .ndo_get_stats64 = dev_get_tstats64,
447 .ndo_set_mac_address = br_set_mac_address,
448 .ndo_set_rx_mode = br_dev_set_multicast_list,
449 .ndo_change_rx_flags = br_dev_change_rx_flags,
450 .ndo_change_mtu = br_change_mtu,
451 .ndo_siocdevprivate = br_dev_siocdevprivate,
452 #ifdef CONFIG_NET_POLL_CONTROLLER
453 .ndo_netpoll_setup = br_netpoll_setup,
454 .ndo_netpoll_cleanup = br_netpoll_cleanup,
455 .ndo_poll_controller = br_poll_controller,
457 .ndo_add_slave = br_add_slave,
458 .ndo_del_slave = br_del_slave,
459 .ndo_fix_features = br_fix_features,
460 .ndo_fdb_add = br_fdb_add,
461 .ndo_fdb_del = br_fdb_delete,
462 .ndo_fdb_del_bulk = br_fdb_delete_bulk,
463 .ndo_fdb_dump = br_fdb_dump,
464 .ndo_fdb_get = br_fdb_get,
465 .ndo_mdb_add = br_mdb_add,
466 .ndo_mdb_del = br_mdb_del,
467 .ndo_mdb_del_bulk = br_mdb_del_bulk,
468 .ndo_mdb_dump = br_mdb_dump,
469 .ndo_mdb_get = br_mdb_get,
470 .ndo_bridge_getlink = br_getlink,
471 .ndo_bridge_setlink = br_setlink,
472 .ndo_bridge_dellink = br_dellink,
473 .ndo_features_check = passthru_features_check,
474 .ndo_fill_forward_path = br_fill_forward_path,
477 static struct device_type br_type = {
481 void br_dev_setup(struct net_device *dev)
483 struct net_bridge *br = netdev_priv(dev);
485 eth_hw_addr_random(dev);
488 dev->netdev_ops = &br_netdev_ops;
489 dev->needs_free_netdev = true;
490 dev->ethtool_ops = &br_ethtool_ops;
491 SET_NETDEV_DEVTYPE(dev, &br_type);
492 dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE;
494 dev->features = COMMON_FEATURES | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL |
495 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
496 dev->hw_features = COMMON_FEATURES | NETIF_F_HW_VLAN_CTAG_TX |
497 NETIF_F_HW_VLAN_STAG_TX;
498 dev->vlan_features = COMMON_FEATURES;
501 spin_lock_init(&br->lock);
502 INIT_LIST_HEAD(&br->port_list);
503 INIT_HLIST_HEAD(&br->fdb_list);
504 INIT_HLIST_HEAD(&br->frame_type_list);
505 #if IS_ENABLED(CONFIG_BRIDGE_MRP)
506 INIT_HLIST_HEAD(&br->mrp_list);
508 #if IS_ENABLED(CONFIG_BRIDGE_CFM)
509 INIT_HLIST_HEAD(&br->mep_list);
511 spin_lock_init(&br->hash_lock);
513 br->bridge_id.prio[0] = 0x80;
514 br->bridge_id.prio[1] = 0x00;
516 ether_addr_copy(br->group_addr, eth_stp_addr);
518 br->stp_enabled = BR_NO_STP;
519 br->group_fwd_mask = BR_GROUPFWD_DEFAULT;
520 br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT;
522 br->designated_root = br->bridge_id;
523 br->bridge_max_age = br->max_age = 20 * HZ;
524 br->bridge_hello_time = br->hello_time = 2 * HZ;
525 br->bridge_forward_delay = br->forward_delay = 15 * HZ;
526 br->bridge_ageing_time = br->ageing_time = BR_DEFAULT_AGEING_TIME;
527 dev->max_mtu = ETH_MAX_MTU;
529 br_netfilter_rtable_init(br);
530 br_stp_timer_init(br);
531 br_multicast_init(br);
532 INIT_DELAYED_WORK(&br->gc_work, br_fdb_cleanup);