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 static struct lock_class_key bridge_netdev_addr_lock_key;
29 /* net device transmit always called with BH disabled */
30 netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
32 struct net_bridge *br = netdev_priv(dev);
33 struct net_bridge_fdb_entry *dst;
34 struct net_bridge_mdb_entry *mdst;
35 struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats);
36 const struct nf_br_ops *nf_ops;
37 const unsigned char *dest;
42 nf_ops = rcu_dereference(nf_br_ops);
43 if (nf_ops && nf_ops->br_dev_xmit_hook(skb)) {
48 u64_stats_update_begin(&brstats->syncp);
49 brstats->tx_packets++;
50 brstats->tx_bytes += skb->len;
51 u64_stats_update_end(&brstats->syncp);
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);
59 skb_pull(skb, ETH_HLEN);
61 if (!br_allowed_ingress(br, br_vlan_group_rcu(br), skb, &vid))
64 if (IS_ENABLED(CONFIG_INET) &&
65 (eth->h_proto == htons(ETH_P_ARP) ||
66 eth->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);
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);
90 if (br_multicast_rcv(br, NULL, skb, vid)) {
95 mdst = br_mdb_get(br, skb, vid);
96 if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
97 br_multicast_querier_exists(br, eth_hdr(skb)))
98 br_multicast_flood(mdst, skb, false, true);
100 br_flood(br, skb, BR_PKT_MULTICAST, false, true);
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);
111 static void br_set_lockdep_class(struct net_device *dev)
113 lockdep_set_class(&dev->addr_list_lock, &bridge_netdev_addr_lock_key);
116 static int br_dev_init(struct net_device *dev)
118 struct net_bridge *br = netdev_priv(dev);
121 br->stats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
125 err = br_fdb_hash_init(br);
127 free_percpu(br->stats);
131 err = br_mdb_hash_init(br);
133 free_percpu(br->stats);
134 br_fdb_hash_fini(br);
138 err = br_vlan_init(br);
140 free_percpu(br->stats);
141 br_mdb_hash_fini(br);
142 br_fdb_hash_fini(br);
146 err = br_multicast_init_stats(br);
148 free_percpu(br->stats);
150 br_mdb_hash_fini(br);
151 br_fdb_hash_fini(br);
153 br_set_lockdep_class(dev);
158 static void br_dev_uninit(struct net_device *dev)
160 struct net_bridge *br = netdev_priv(dev);
162 br_multicast_dev_del(br);
163 br_multicast_uninit_stats(br);
165 br_mdb_hash_fini(br);
166 br_fdb_hash_fini(br);
167 free_percpu(br->stats);
170 static int br_dev_open(struct net_device *dev)
172 struct net_bridge *br = netdev_priv(dev);
174 netdev_update_features(dev);
175 netif_start_queue(dev);
176 br_stp_enable_bridge(br);
177 br_multicast_open(br);
182 static void br_dev_set_multicast_list(struct net_device *dev)
186 static void br_dev_change_rx_flags(struct net_device *dev, int change)
188 if (change & IFF_PROMISC)
189 br_manage_promisc(netdev_priv(dev));
192 static int br_dev_stop(struct net_device *dev)
194 struct net_bridge *br = netdev_priv(dev);
196 br_stp_disable_bridge(br);
197 br_multicast_stop(br);
199 netif_stop_queue(dev);
204 static void br_get_stats64(struct net_device *dev,
205 struct rtnl_link_stats64 *stats)
207 struct net_bridge *br = netdev_priv(dev);
208 struct pcpu_sw_netstats tmp, sum = { 0 };
211 for_each_possible_cpu(cpu) {
213 const struct pcpu_sw_netstats *bstats
214 = per_cpu_ptr(br->stats, cpu);
216 start = u64_stats_fetch_begin_irq(&bstats->syncp);
217 memcpy(&tmp, bstats, sizeof(tmp));
218 } while (u64_stats_fetch_retry_irq(&bstats->syncp, start));
219 sum.tx_bytes += tmp.tx_bytes;
220 sum.tx_packets += tmp.tx_packets;
221 sum.rx_bytes += tmp.rx_bytes;
222 sum.rx_packets += tmp.rx_packets;
225 stats->tx_bytes = sum.tx_bytes;
226 stats->tx_packets = sum.tx_packets;
227 stats->rx_bytes = sum.rx_bytes;
228 stats->rx_packets = sum.rx_packets;
231 static int br_change_mtu(struct net_device *dev, int new_mtu)
233 struct net_bridge *br = netdev_priv(dev);
237 /* this flag will be cleared if the MTU was automatically adjusted */
238 br_opt_toggle(br, BROPT_MTU_SET_BY_USER, true);
239 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
240 /* remember the MTU in the rtable for PMTU */
241 dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu);
247 /* Allow setting mac address to any valid ethernet address. */
248 static int br_set_mac_address(struct net_device *dev, void *p)
250 struct net_bridge *br = netdev_priv(dev);
251 struct sockaddr *addr = p;
253 if (!is_valid_ether_addr(addr->sa_data))
254 return -EADDRNOTAVAIL;
256 spin_lock_bh(&br->lock);
257 if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) {
258 /* Mac address will be changed in br_stp_change_bridge_id(). */
259 br_stp_change_bridge_id(br, addr->sa_data);
261 spin_unlock_bh(&br->lock);
266 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
268 strlcpy(info->driver, "bridge", sizeof(info->driver));
269 strlcpy(info->version, BR_VERSION, sizeof(info->version));
270 strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
271 strlcpy(info->bus_info, "N/A", sizeof(info->bus_info));
274 static netdev_features_t br_fix_features(struct net_device *dev,
275 netdev_features_t features)
277 struct net_bridge *br = netdev_priv(dev);
279 return br_features_recompute(br, features);
282 #ifdef CONFIG_NET_POLL_CONTROLLER
283 static void br_poll_controller(struct net_device *br_dev)
287 static void br_netpoll_cleanup(struct net_device *dev)
289 struct net_bridge *br = netdev_priv(dev);
290 struct net_bridge_port *p;
292 list_for_each_entry(p, &br->port_list, list)
293 br_netpoll_disable(p);
296 static int __br_netpoll_enable(struct net_bridge_port *p)
301 np = kzalloc(sizeof(*p->np), GFP_KERNEL);
305 err = __netpoll_setup(np, p->dev);
315 int br_netpoll_enable(struct net_bridge_port *p)
317 if (!p->br->dev->npinfo)
320 return __br_netpoll_enable(p);
323 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
325 struct net_bridge *br = netdev_priv(dev);
326 struct net_bridge_port *p;
329 list_for_each_entry(p, &br->port_list, list) {
332 err = __br_netpoll_enable(p);
341 br_netpoll_cleanup(dev);
345 void br_netpoll_disable(struct net_bridge_port *p)
347 struct netpoll *np = p->np;
359 static int br_add_slave(struct net_device *dev, struct net_device *slave_dev,
360 struct netlink_ext_ack *extack)
363 struct net_bridge *br = netdev_priv(dev);
365 return br_add_if(br, slave_dev, extack);
368 static int br_del_slave(struct net_device *dev, struct net_device *slave_dev)
370 struct net_bridge *br = netdev_priv(dev);
372 return br_del_if(br, slave_dev);
375 static const struct ethtool_ops br_ethtool_ops = {
376 .get_drvinfo = br_getinfo,
377 .get_link = ethtool_op_get_link,
380 static const struct net_device_ops br_netdev_ops = {
381 .ndo_open = br_dev_open,
382 .ndo_stop = br_dev_stop,
383 .ndo_init = br_dev_init,
384 .ndo_uninit = br_dev_uninit,
385 .ndo_start_xmit = br_dev_xmit,
386 .ndo_get_stats64 = br_get_stats64,
387 .ndo_set_mac_address = br_set_mac_address,
388 .ndo_set_rx_mode = br_dev_set_multicast_list,
389 .ndo_change_rx_flags = br_dev_change_rx_flags,
390 .ndo_change_mtu = br_change_mtu,
391 .ndo_do_ioctl = br_dev_ioctl,
392 #ifdef CONFIG_NET_POLL_CONTROLLER
393 .ndo_netpoll_setup = br_netpoll_setup,
394 .ndo_netpoll_cleanup = br_netpoll_cleanup,
395 .ndo_poll_controller = br_poll_controller,
397 .ndo_add_slave = br_add_slave,
398 .ndo_del_slave = br_del_slave,
399 .ndo_fix_features = br_fix_features,
400 .ndo_fdb_add = br_fdb_add,
401 .ndo_fdb_del = br_fdb_delete,
402 .ndo_fdb_dump = br_fdb_dump,
403 .ndo_fdb_get = br_fdb_get,
404 .ndo_bridge_getlink = br_getlink,
405 .ndo_bridge_setlink = br_setlink,
406 .ndo_bridge_dellink = br_dellink,
407 .ndo_features_check = passthru_features_check,
410 static struct device_type br_type = {
414 void br_dev_setup(struct net_device *dev)
416 struct net_bridge *br = netdev_priv(dev);
418 eth_hw_addr_random(dev);
421 dev->netdev_ops = &br_netdev_ops;
422 dev->needs_free_netdev = true;
423 dev->ethtool_ops = &br_ethtool_ops;
424 SET_NETDEV_DEVTYPE(dev, &br_type);
425 dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE;
427 dev->features = COMMON_FEATURES | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL |
428 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
429 dev->hw_features = COMMON_FEATURES | NETIF_F_HW_VLAN_CTAG_TX |
430 NETIF_F_HW_VLAN_STAG_TX;
431 dev->vlan_features = COMMON_FEATURES;
434 spin_lock_init(&br->lock);
435 INIT_LIST_HEAD(&br->port_list);
436 INIT_HLIST_HEAD(&br->fdb_list);
437 spin_lock_init(&br->hash_lock);
439 br->bridge_id.prio[0] = 0x80;
440 br->bridge_id.prio[1] = 0x00;
442 ether_addr_copy(br->group_addr, eth_stp_addr);
444 br->stp_enabled = BR_NO_STP;
445 br->group_fwd_mask = BR_GROUPFWD_DEFAULT;
446 br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT;
448 br->designated_root = br->bridge_id;
449 br->bridge_max_age = br->max_age = 20 * HZ;
450 br->bridge_hello_time = br->hello_time = 2 * HZ;
451 br->bridge_forward_delay = br->forward_delay = 15 * HZ;
452 br->bridge_ageing_time = br->ageing_time = BR_DEFAULT_AGEING_TIME;
453 dev->max_mtu = ETH_MAX_MTU;
455 br_netfilter_rtable_init(br);
456 br_stp_timer_init(br);
457 br_multicast_init(br);
458 INIT_DELAYED_WORK(&br->gc_work, br_fdb_cleanup);