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 *br = netdev_priv(dev);
31 struct net_bridge_fdb_entry *dst;
32 struct net_bridge_mdb_entry *mdst;
33 struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats);
34 const struct nf_br_ops *nf_ops;
35 u8 state = BR_STATE_FORWARDING;
36 const unsigned char *dest;
41 nf_ops = rcu_dereference(nf_br_ops);
42 if (nf_ops && nf_ops->br_dev_xmit_hook(skb)) {
47 u64_stats_update_begin(&brstats->syncp);
48 brstats->tx_packets++;
49 brstats->tx_bytes += skb->len;
50 u64_stats_update_end(&brstats->syncp);
52 br_switchdev_frame_unmark(skb);
53 BR_INPUT_SKB_CB(skb)->brdev = dev;
54 BR_INPUT_SKB_CB(skb)->frag_max_size = 0;
56 skb_reset_mac_header(skb);
58 skb_pull(skb, ETH_HLEN);
60 if (!br_allowed_ingress(br, br_vlan_group_rcu(br), skb, &vid, &state))
63 if (IS_ENABLED(CONFIG_INET) &&
64 (eth->h_proto == htons(ETH_P_ARP) ||
65 eth->h_proto == htons(ETH_P_RARP)) &&
66 br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) {
67 br_do_proxy_suppress_arp(skb, br, vid, NULL);
68 } else if (IS_ENABLED(CONFIG_IPV6) &&
69 skb->protocol == htons(ETH_P_IPV6) &&
70 br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED) &&
71 pskb_may_pull(skb, sizeof(struct ipv6hdr) +
72 sizeof(struct nd_msg)) &&
73 ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) {
74 struct nd_msg *msg, _msg;
76 msg = br_is_nd_neigh_msg(skb, &_msg);
78 br_do_suppress_nd(skb, br, vid, NULL, msg);
81 dest = eth_hdr(skb)->h_dest;
82 if (is_broadcast_ether_addr(dest)) {
83 br_flood(br, skb, BR_PKT_BROADCAST, false, true);
84 } else if (is_multicast_ether_addr(dest)) {
85 if (unlikely(netpoll_tx_running(dev))) {
86 br_flood(br, skb, BR_PKT_MULTICAST, false, true);
89 if (br_multicast_rcv(br, NULL, skb, vid)) {
94 mdst = br_mdb_get(br, skb, vid);
95 if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
96 br_multicast_querier_exists(br, eth_hdr(skb)))
97 br_multicast_flood(mdst, skb, false, true);
99 br_flood(br, skb, BR_PKT_MULTICAST, false, true);
100 } else if ((dst = br_fdb_find_rcu(br, dest, vid)) != NULL) {
101 br_forward(dst->dst, skb, false, true);
103 br_flood(br, skb, BR_PKT_UNICAST, false, true);
110 static int br_dev_init(struct net_device *dev)
112 struct net_bridge *br = netdev_priv(dev);
115 br->stats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
119 err = br_fdb_hash_init(br);
121 free_percpu(br->stats);
125 err = br_mdb_hash_init(br);
127 free_percpu(br->stats);
128 br_fdb_hash_fini(br);
132 err = br_vlan_init(br);
134 free_percpu(br->stats);
135 br_mdb_hash_fini(br);
136 br_fdb_hash_fini(br);
140 err = br_multicast_init_stats(br);
142 free_percpu(br->stats);
144 br_mdb_hash_fini(br);
145 br_fdb_hash_fini(br);
151 static void br_dev_uninit(struct net_device *dev)
153 struct net_bridge *br = netdev_priv(dev);
155 br_multicast_dev_del(br);
156 br_multicast_uninit_stats(br);
158 br_mdb_hash_fini(br);
159 br_fdb_hash_fini(br);
160 free_percpu(br->stats);
163 static int br_dev_open(struct net_device *dev)
165 struct net_bridge *br = netdev_priv(dev);
167 netdev_update_features(dev);
168 netif_start_queue(dev);
169 br_stp_enable_bridge(br);
170 br_multicast_open(br);
175 static void br_dev_set_multicast_list(struct net_device *dev)
179 static void br_dev_change_rx_flags(struct net_device *dev, int change)
181 if (change & IFF_PROMISC)
182 br_manage_promisc(netdev_priv(dev));
185 static int br_dev_stop(struct net_device *dev)
187 struct net_bridge *br = netdev_priv(dev);
189 br_stp_disable_bridge(br);
190 br_multicast_stop(br);
192 netif_stop_queue(dev);
197 static void br_get_stats64(struct net_device *dev,
198 struct rtnl_link_stats64 *stats)
200 struct net_bridge *br = netdev_priv(dev);
201 struct pcpu_sw_netstats tmp, sum = { 0 };
204 for_each_possible_cpu(cpu) {
206 const struct pcpu_sw_netstats *bstats
207 = per_cpu_ptr(br->stats, cpu);
209 start = u64_stats_fetch_begin_irq(&bstats->syncp);
210 memcpy(&tmp, bstats, sizeof(tmp));
211 } while (u64_stats_fetch_retry_irq(&bstats->syncp, start));
212 sum.tx_bytes += tmp.tx_bytes;
213 sum.tx_packets += tmp.tx_packets;
214 sum.rx_bytes += tmp.rx_bytes;
215 sum.rx_packets += tmp.rx_packets;
218 stats->tx_bytes = sum.tx_bytes;
219 stats->tx_packets = sum.tx_packets;
220 stats->rx_bytes = sum.rx_bytes;
221 stats->rx_packets = sum.rx_packets;
224 static int br_change_mtu(struct net_device *dev, int new_mtu)
226 struct net_bridge *br = netdev_priv(dev);
230 /* this flag will be cleared if the MTU was automatically adjusted */
231 br_opt_toggle(br, BROPT_MTU_SET_BY_USER, true);
232 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
233 /* remember the MTU in the rtable for PMTU */
234 dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu);
240 /* Allow setting mac address to any valid ethernet address. */
241 static int br_set_mac_address(struct net_device *dev, void *p)
243 struct net_bridge *br = netdev_priv(dev);
244 struct sockaddr *addr = p;
246 if (!is_valid_ether_addr(addr->sa_data))
247 return -EADDRNOTAVAIL;
249 /* dev_set_mac_addr() can be called by a master device on bridge's
250 * NETDEV_UNREGISTER, but since it's being destroyed do nothing
252 if (dev->reg_state != NETREG_REGISTERED)
255 spin_lock_bh(&br->lock);
256 if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) {
257 /* Mac address will be changed in br_stp_change_bridge_id(). */
258 br_stp_change_bridge_id(br, addr->sa_data);
260 spin_unlock_bh(&br->lock);
265 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
267 strlcpy(info->driver, "bridge", sizeof(info->driver));
268 strlcpy(info->version, BR_VERSION, sizeof(info->version));
269 strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
270 strlcpy(info->bus_info, "N/A", sizeof(info->bus_info));
273 static int br_get_link_ksettings(struct net_device *dev,
274 struct ethtool_link_ksettings *cmd)
276 struct net_bridge *br = netdev_priv(dev);
277 struct net_bridge_port *p;
279 cmd->base.duplex = DUPLEX_UNKNOWN;
280 cmd->base.port = PORT_OTHER;
281 cmd->base.speed = SPEED_UNKNOWN;
283 list_for_each_entry(p, &br->port_list, list) {
284 struct ethtool_link_ksettings ecmd;
285 struct net_device *pdev = p->dev;
287 if (!netif_running(pdev) || !netif_oper_up(pdev))
290 if (__ethtool_get_link_ksettings(pdev, &ecmd))
293 if (ecmd.base.speed == (__u32)SPEED_UNKNOWN)
296 if (cmd->base.speed == (__u32)SPEED_UNKNOWN ||
297 cmd->base.speed < ecmd.base.speed)
298 cmd->base.speed = ecmd.base.speed;
304 static netdev_features_t br_fix_features(struct net_device *dev,
305 netdev_features_t features)
307 struct net_bridge *br = netdev_priv(dev);
309 return br_features_recompute(br, features);
312 #ifdef CONFIG_NET_POLL_CONTROLLER
313 static void br_poll_controller(struct net_device *br_dev)
317 static void br_netpoll_cleanup(struct net_device *dev)
319 struct net_bridge *br = netdev_priv(dev);
320 struct net_bridge_port *p;
322 list_for_each_entry(p, &br->port_list, list)
323 br_netpoll_disable(p);
326 static int __br_netpoll_enable(struct net_bridge_port *p)
331 np = kzalloc(sizeof(*p->np), GFP_KERNEL);
335 err = __netpoll_setup(np, p->dev);
345 int br_netpoll_enable(struct net_bridge_port *p)
347 if (!p->br->dev->npinfo)
350 return __br_netpoll_enable(p);
353 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
355 struct net_bridge *br = netdev_priv(dev);
356 struct net_bridge_port *p;
359 list_for_each_entry(p, &br->port_list, list) {
362 err = __br_netpoll_enable(p);
371 br_netpoll_cleanup(dev);
375 void br_netpoll_disable(struct net_bridge_port *p)
377 struct netpoll *np = p->np;
389 static int br_add_slave(struct net_device *dev, struct net_device *slave_dev,
390 struct netlink_ext_ack *extack)
393 struct net_bridge *br = netdev_priv(dev);
395 return br_add_if(br, slave_dev, extack);
398 static int br_del_slave(struct net_device *dev, struct net_device *slave_dev)
400 struct net_bridge *br = netdev_priv(dev);
402 return br_del_if(br, slave_dev);
405 static const struct ethtool_ops br_ethtool_ops = {
406 .get_drvinfo = br_getinfo,
407 .get_link = ethtool_op_get_link,
408 .get_link_ksettings = br_get_link_ksettings,
411 static const struct net_device_ops br_netdev_ops = {
412 .ndo_open = br_dev_open,
413 .ndo_stop = br_dev_stop,
414 .ndo_init = br_dev_init,
415 .ndo_uninit = br_dev_uninit,
416 .ndo_start_xmit = br_dev_xmit,
417 .ndo_get_stats64 = br_get_stats64,
418 .ndo_set_mac_address = br_set_mac_address,
419 .ndo_set_rx_mode = br_dev_set_multicast_list,
420 .ndo_change_rx_flags = br_dev_change_rx_flags,
421 .ndo_change_mtu = br_change_mtu,
422 .ndo_do_ioctl = br_dev_ioctl,
423 #ifdef CONFIG_NET_POLL_CONTROLLER
424 .ndo_netpoll_setup = br_netpoll_setup,
425 .ndo_netpoll_cleanup = br_netpoll_cleanup,
426 .ndo_poll_controller = br_poll_controller,
428 .ndo_add_slave = br_add_slave,
429 .ndo_del_slave = br_del_slave,
430 .ndo_fix_features = br_fix_features,
431 .ndo_fdb_add = br_fdb_add,
432 .ndo_fdb_del = br_fdb_delete,
433 .ndo_fdb_dump = br_fdb_dump,
434 .ndo_fdb_get = br_fdb_get,
435 .ndo_bridge_getlink = br_getlink,
436 .ndo_bridge_setlink = br_setlink,
437 .ndo_bridge_dellink = br_dellink,
438 .ndo_features_check = passthru_features_check,
441 static struct device_type br_type = {
445 void br_dev_setup(struct net_device *dev)
447 struct net_bridge *br = netdev_priv(dev);
449 eth_hw_addr_random(dev);
452 dev->netdev_ops = &br_netdev_ops;
453 dev->needs_free_netdev = true;
454 dev->ethtool_ops = &br_ethtool_ops;
455 SET_NETDEV_DEVTYPE(dev, &br_type);
456 dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE;
458 dev->features = COMMON_FEATURES | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL |
459 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
460 dev->hw_features = COMMON_FEATURES | NETIF_F_HW_VLAN_CTAG_TX |
461 NETIF_F_HW_VLAN_STAG_TX;
462 dev->vlan_features = COMMON_FEATURES;
465 spin_lock_init(&br->lock);
466 INIT_LIST_HEAD(&br->port_list);
467 INIT_HLIST_HEAD(&br->fdb_list);
468 spin_lock_init(&br->hash_lock);
470 br->bridge_id.prio[0] = 0x80;
471 br->bridge_id.prio[1] = 0x00;
473 ether_addr_copy(br->group_addr, eth_stp_addr);
475 br->stp_enabled = BR_NO_STP;
476 br->group_fwd_mask = BR_GROUPFWD_DEFAULT;
477 br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT;
479 br->designated_root = br->bridge_id;
480 br->bridge_max_age = br->max_age = 20 * HZ;
481 br->bridge_hello_time = br->hello_time = 2 * HZ;
482 br->bridge_forward_delay = br->forward_delay = 15 * HZ;
483 br->bridge_ageing_time = br->ageing_time = BR_DEFAULT_AGEING_TIME;
484 dev->max_mtu = ETH_MAX_MTU;
486 br_netfilter_rtable_init(br);
487 br_stp_timer_init(br);
488 br_multicast_init(br);
489 INIT_DELAYED_WORK(&br->gc_work, br_fdb_cleanup);