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 24const struct nf_br_ops __rcu *nf_br_ops __read_mostly; 25EXPORT_SYMBOL_GPL(nf_br_ops); 26 27/* net device transmit always called with BH disabled */ 28netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev) 29{ 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; 37 u16 vid = 0; 38 39 memset(skb->cb, 0, sizeof(struct br_input_skb_cb)); 40 41 rcu_read_lock(); 42 nf_ops = rcu_dereference(nf_br_ops); 43 if (nf_ops && nf_ops->br_dev_xmit_hook(skb)) { 44 rcu_read_unlock(); 45 return NETDEV_TX_OK; 46 } 47 48 u64_stats_update_begin(&brstats->syncp); 49 brstats->tx_packets++; 50 brstats->tx_bytes += skb->len; 51 u64_stats_update_end(&brstats->syncp); 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, br_vlan_group_rcu(br), skb, &vid, &state)) 61 goto out; 62 63 if (IS_ENABLED(CONFIG_INET) && 64 (eth_hdr(skb)->h_proto == htons(ETH_P_ARP) || 65 eth_hdr(skb)->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; 75 76 msg = br_is_nd_neigh_msg(skb, &_msg); 77 if (msg) 78 br_do_suppress_nd(skb, br, vid, NULL, msg); 79 } 80 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); 87 goto out; 88 } 89 if (br_multicast_rcv(br, NULL, skb, vid)) { 90 kfree_skb(skb); 91 goto out; 92 } 93 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); 98 else 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); 102 } else { 103 br_flood(br, skb, BR_PKT_UNICAST, false, true); 104 } 105out: 106 rcu_read_unlock(); 107 return NETDEV_TX_OK; 108} 109 110static struct lock_class_key bridge_netdev_addr_lock_key; 111 112static void br_set_lockdep_class(struct net_device *dev) 113{ 114 lockdep_set_class(&dev->addr_list_lock, &bridge_netdev_addr_lock_key); 115} 116 117static int br_dev_init(struct net_device *dev) 118{ 119 struct net_bridge *br = netdev_priv(dev); 120 int err; 121 122 br->stats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 123 if (!br->stats) 124 return -ENOMEM; 125 126 err = br_fdb_hash_init(br); 127 if (err) { 128 free_percpu(br->stats); 129 return err; 130 } 131 132 err = br_mdb_hash_init(br); 133 if (err) { 134 free_percpu(br->stats); 135 br_fdb_hash_fini(br); 136 return err; 137 } 138 139 err = br_vlan_init(br); 140 if (err) { 141 free_percpu(br->stats); 142 br_mdb_hash_fini(br); 143 br_fdb_hash_fini(br); 144 return err; 145 } 146 147 err = br_multicast_init_stats(br); 148 if (err) { 149 free_percpu(br->stats); 150 br_vlan_flush(br); 151 br_mdb_hash_fini(br); 152 br_fdb_hash_fini(br); 153 } 154 155 br_set_lockdep_class(dev); 156 return err; 157} 158 159static void br_dev_uninit(struct net_device *dev) 160{ 161 struct net_bridge *br = netdev_priv(dev); 162 163 br_multicast_dev_del(br); 164 br_multicast_uninit_stats(br); 165 br_vlan_flush(br); 166 br_mdb_hash_fini(br); 167 br_fdb_hash_fini(br); 168 free_percpu(br->stats); 169} 170 171static int br_dev_open(struct net_device *dev) 172{ 173 struct net_bridge *br = netdev_priv(dev); 174 175 netdev_update_features(dev); 176 netif_start_queue(dev); 177 br_stp_enable_bridge(br); 178 br_multicast_open(br); 179 180 if (br_opt_get(br, BROPT_MULTICAST_ENABLED)) 181 br_multicast_join_snoopers(br); 182 183 return 0; 184} 185 186static void br_dev_set_multicast_list(struct net_device *dev) 187{ 188} 189 190static void br_dev_change_rx_flags(struct net_device *dev, int change) 191{ 192 if (change & IFF_PROMISC) 193 br_manage_promisc(netdev_priv(dev)); 194} 195 196static int br_dev_stop(struct net_device *dev) 197{ 198 struct net_bridge *br = netdev_priv(dev); 199 200 br_stp_disable_bridge(br); 201 br_multicast_stop(br); 202 203 if (br_opt_get(br, BROPT_MULTICAST_ENABLED)) 204 br_multicast_leave_snoopers(br); 205 206 netif_stop_queue(dev); 207 208 return 0; 209} 210 211static void br_get_stats64(struct net_device *dev, 212 struct rtnl_link_stats64 *stats) 213{ 214 struct net_bridge *br = netdev_priv(dev); 215 216 netdev_stats_to_stats64(stats, &dev->stats); 217 dev_fetch_sw_netstats(stats, br->stats); 218} 219 220static int br_change_mtu(struct net_device *dev, int new_mtu) 221{ 222 struct net_bridge *br = netdev_priv(dev); 223 224 dev->mtu = new_mtu; 225 226 /* this flag will be cleared if the MTU was automatically adjusted */ 227 br_opt_toggle(br, BROPT_MTU_SET_BY_USER, true); 228#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 229 /* remember the MTU in the rtable for PMTU */ 230 dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu); 231#endif 232 233 return 0; 234} 235 236/* Allow setting mac address to any valid ethernet address. */ 237static int br_set_mac_address(struct net_device *dev, void *p) 238{ 239 struct net_bridge *br = netdev_priv(dev); 240 struct sockaddr *addr = p; 241 242 if (!is_valid_ether_addr(addr->sa_data)) 243 return -EADDRNOTAVAIL; 244 245 /* dev_set_mac_addr() can be called by a master device on bridge's 246 * NETDEV_UNREGISTER, but since it's being destroyed do nothing 247 */ 248 if (dev->reg_state != NETREG_REGISTERED) 249 return -EBUSY; 250 251 spin_lock_bh(&br->lock); 252 if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) { 253 /* Mac address will be changed in br_stp_change_bridge_id(). */ 254 br_stp_change_bridge_id(br, addr->sa_data); 255 } 256 spin_unlock_bh(&br->lock); 257 258 return 0; 259} 260 261static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) 262{ 263 strlcpy(info->driver, "bridge", sizeof(info->driver)); 264 strlcpy(info->version, BR_VERSION, sizeof(info->version)); 265 strlcpy(info->fw_version, "N/A", sizeof(info->fw_version)); 266 strlcpy(info->bus_info, "N/A", sizeof(info->bus_info)); 267} 268 269static int br_get_link_ksettings(struct net_device *dev, 270 struct ethtool_link_ksettings *cmd) 271{ 272 struct net_bridge *br = netdev_priv(dev); 273 struct net_bridge_port *p; 274 275 cmd->base.duplex = DUPLEX_UNKNOWN; 276 cmd->base.port = PORT_OTHER; 277 cmd->base.speed = SPEED_UNKNOWN; 278 279 list_for_each_entry(p, &br->port_list, list) { 280 struct ethtool_link_ksettings ecmd; 281 struct net_device *pdev = p->dev; 282 283 if (!netif_running(pdev) || !netif_oper_up(pdev)) 284 continue; 285 286 if (__ethtool_get_link_ksettings(pdev, &ecmd)) 287 continue; 288 289 if (ecmd.base.speed == (__u32)SPEED_UNKNOWN) 290 continue; 291 292 if (cmd->base.speed == (__u32)SPEED_UNKNOWN || 293 cmd->base.speed < ecmd.base.speed) 294 cmd->base.speed = ecmd.base.speed; 295 } 296 297 return 0; 298} 299 300static netdev_features_t br_fix_features(struct net_device *dev, 301 netdev_features_t features) 302{ 303 struct net_bridge *br = netdev_priv(dev); 304 305 return br_features_recompute(br, features); 306} 307 308#ifdef CONFIG_NET_POLL_CONTROLLER 309static void br_poll_controller(struct net_device *br_dev) 310{ 311} 312 313static void br_netpoll_cleanup(struct net_device *dev) 314{ 315 struct net_bridge *br = netdev_priv(dev); 316 struct net_bridge_port *p; 317 318 list_for_each_entry(p, &br->port_list, list) 319 br_netpoll_disable(p); 320} 321 322static int __br_netpoll_enable(struct net_bridge_port *p) 323{ 324 struct netpoll *np; 325 int err; 326 327 np = kzalloc(sizeof(*p->np), GFP_KERNEL); 328 if (!np) 329 return -ENOMEM; 330 331 err = __netpoll_setup(np, p->dev); 332 if (err) { 333 kfree(np); 334 return err; 335 } 336 337 p->np = np; 338 return err; 339} 340 341int br_netpoll_enable(struct net_bridge_port *p) 342{ 343 if (!p->br->dev->npinfo) 344 return 0; 345 346 return __br_netpoll_enable(p); 347} 348 349static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni) 350{ 351 struct net_bridge *br = netdev_priv(dev); 352 struct net_bridge_port *p; 353 int err = 0; 354 355 list_for_each_entry(p, &br->port_list, list) { 356 if (!p->dev) 357 continue; 358 err = __br_netpoll_enable(p); 359 if (err) 360 goto fail; 361 } 362 363out: 364 return err; 365 366fail: 367 br_netpoll_cleanup(dev); 368 goto out; 369} 370 371void br_netpoll_disable(struct net_bridge_port *p) 372{ 373 struct netpoll *np = p->np; 374 375 if (!np) 376 return; 377 378 p->np = NULL; 379 380 __netpoll_free(np); 381} 382 383#endif 384 385static int br_add_slave(struct net_device *dev, struct net_device *slave_dev, 386 struct netlink_ext_ack *extack) 387 388{ 389 struct net_bridge *br = netdev_priv(dev); 390 391 return br_add_if(br, slave_dev, extack); 392} 393 394static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) 395{ 396 struct net_bridge *br = netdev_priv(dev); 397 398 return br_del_if(br, slave_dev); 399} 400 401static const struct ethtool_ops br_ethtool_ops = { 402 .get_drvinfo = br_getinfo, 403 .get_link = ethtool_op_get_link, 404 .get_link_ksettings = br_get_link_ksettings, 405}; 406 407static const struct net_device_ops br_netdev_ops = { 408 .ndo_open = br_dev_open, 409 .ndo_stop = br_dev_stop, 410 .ndo_init = br_dev_init, 411 .ndo_uninit = br_dev_uninit, 412 .ndo_start_xmit = br_dev_xmit, 413 .ndo_get_stats64 = br_get_stats64, 414 .ndo_set_mac_address = br_set_mac_address, 415 .ndo_set_rx_mode = br_dev_set_multicast_list, 416 .ndo_change_rx_flags = br_dev_change_rx_flags, 417 .ndo_change_mtu = br_change_mtu, 418 .ndo_do_ioctl = br_dev_ioctl, 419#ifdef CONFIG_NET_POLL_CONTROLLER 420 .ndo_netpoll_setup = br_netpoll_setup, 421 .ndo_netpoll_cleanup = br_netpoll_cleanup, 422 .ndo_poll_controller = br_poll_controller, 423#endif 424 .ndo_add_slave = br_add_slave, 425 .ndo_del_slave = br_del_slave, 426 .ndo_fix_features = br_fix_features, 427 .ndo_fdb_add = br_fdb_add, 428 .ndo_fdb_del = br_fdb_delete, 429 .ndo_fdb_dump = br_fdb_dump, 430 .ndo_fdb_get = br_fdb_get, 431 .ndo_bridge_getlink = br_getlink, 432 .ndo_bridge_setlink = br_setlink, 433 .ndo_bridge_dellink = br_dellink, 434 .ndo_features_check = passthru_features_check, 435}; 436 437static struct device_type br_type = { 438 .name = "bridge", 439}; 440 441void br_dev_setup(struct net_device *dev) 442{ 443 struct net_bridge *br = netdev_priv(dev); 444 445 eth_hw_addr_random(dev); 446 ether_setup(dev); 447 448 dev->netdev_ops = &br_netdev_ops; 449 dev->needs_free_netdev = true; 450 dev->ethtool_ops = &br_ethtool_ops; 451 SET_NETDEV_DEVTYPE(dev, &br_type); 452 dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE; 453 454 dev->features = COMMON_FEATURES | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL | 455 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX; 456 dev->hw_features = COMMON_FEATURES | NETIF_F_HW_VLAN_CTAG_TX | 457 NETIF_F_HW_VLAN_STAG_TX; 458 dev->vlan_features = COMMON_FEATURES; 459 460 br->dev = dev; 461 spin_lock_init(&br->lock); 462 INIT_LIST_HEAD(&br->port_list); 463 INIT_HLIST_HEAD(&br->fdb_list); 464#if IS_ENABLED(CONFIG_BRIDGE_MRP) 465 INIT_LIST_HEAD(&br->mrp_list); 466#endif 467 spin_lock_init(&br->hash_lock); 468 469 br->bridge_id.prio[0] = 0x80; 470 br->bridge_id.prio[1] = 0x00; 471 472 ether_addr_copy(br->group_addr, eth_stp_addr); 473 474 br->stp_enabled = BR_NO_STP; 475 br->group_fwd_mask = BR_GROUPFWD_DEFAULT; 476 br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT; 477 478 br->designated_root = br->bridge_id; 479 br->bridge_max_age = br->max_age = 20 * HZ; 480 br->bridge_hello_time = br->hello_time = 2 * HZ; 481 br->bridge_forward_delay = br->forward_delay = 15 * HZ; 482 br->bridge_ageing_time = br->ageing_time = BR_DEFAULT_AGEING_TIME; 483 dev->max_mtu = ETH_MAX_MTU; 484 485 br_netfilter_rtable_init(br); 486 br_stp_timer_init(br); 487 br_multicast_init(br); 488 INIT_DELAYED_WORK(&br->gc_work, br_fdb_cleanup); 489} 490