1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Generic parts 4 * Linux ethernet bridge 5 * 6 * Authors: 7 * Lennert Buytenhek <buytenh@gnu.org> 8 */ 9 10 #include <linux/module.h> 11 #include <linux/kernel.h> 12 #include <linux/netdevice.h> 13 #include <linux/etherdevice.h> 14 #include <linux/init.h> 15 #include <linux/llc.h> 16 #include <net/llc.h> 17 #include <net/stp.h> 18 #include <net/switchdev.h> 19 20 #include "br_private.h" 21 22 /* 23 * Handle changes in state of network devices enslaved to a bridge. 24 * 25 * Note: don't care about up/down if bridge itself is down, because 26 * port state is checked when bridge is brought up. 27 */ 28 static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr) 29 { 30 struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr); 31 struct netdev_notifier_pre_changeaddr_info *prechaddr_info; 32 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 33 struct net_bridge_port *p; 34 struct net_bridge *br; 35 bool notified = false; 36 bool changed_addr; 37 int err; 38 39 if (netif_is_bridge_master(dev)) { 40 err = br_vlan_bridge_event(dev, event, ptr); 41 if (err) 42 return notifier_from_errno(err); 43 44 if (event == NETDEV_REGISTER) { 45 /* register of bridge completed, add sysfs entries */ 46 err = br_sysfs_addbr(dev); 47 if (err) 48 return notifier_from_errno(err); 49 50 return NOTIFY_DONE; 51 } 52 } 53 54 if (is_vlan_dev(dev)) { 55 struct net_device *real_dev = vlan_dev_real_dev(dev); 56 57 if (netif_is_bridge_master(real_dev)) 58 br_vlan_vlan_upper_event(real_dev, dev, event); 59 } 60 61 /* not a port of a bridge */ 62 p = br_port_get_rtnl(dev); 63 if (!p) 64 return NOTIFY_DONE; 65 66 br = p->br; 67 68 switch (event) { 69 case NETDEV_CHANGEMTU: 70 br_mtu_auto_adjust(br); 71 break; 72 73 case NETDEV_PRE_CHANGEADDR: 74 if (br->dev->addr_assign_type == NET_ADDR_SET) 75 break; 76 prechaddr_info = ptr; 77 err = dev_pre_changeaddr_notify(br->dev, 78 prechaddr_info->dev_addr, 79 extack); 80 if (err) 81 return notifier_from_errno(err); 82 break; 83 84 case NETDEV_CHANGEADDR: 85 spin_lock_bh(&br->lock); 86 br_fdb_changeaddr(p, dev->dev_addr); 87 changed_addr = br_stp_recalculate_bridge_id(br); 88 spin_unlock_bh(&br->lock); 89 90 if (changed_addr) 91 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev); 92 93 break; 94 95 case NETDEV_CHANGE: 96 br_port_carrier_check(p, ¬ified); 97 break; 98 99 case NETDEV_FEAT_CHANGE: 100 netdev_update_features(br->dev); 101 break; 102 103 case NETDEV_DOWN: 104 spin_lock_bh(&br->lock); 105 if (br->dev->flags & IFF_UP) { 106 br_stp_disable_port(p); 107 notified = true; 108 } 109 spin_unlock_bh(&br->lock); 110 break; 111 112 case NETDEV_UP: 113 if (netif_running(br->dev) && netif_oper_up(dev)) { 114 spin_lock_bh(&br->lock); 115 br_stp_enable_port(p); 116 notified = true; 117 spin_unlock_bh(&br->lock); 118 } 119 break; 120 121 case NETDEV_UNREGISTER: 122 br_del_if(br, dev); 123 break; 124 125 case NETDEV_CHANGENAME: 126 err = br_sysfs_renameif(p); 127 if (err) 128 return notifier_from_errno(err); 129 break; 130 131 case NETDEV_PRE_TYPE_CHANGE: 132 /* Forbid underlying device to change its type. */ 133 return NOTIFY_BAD; 134 135 case NETDEV_RESEND_IGMP: 136 /* Propagate to master device */ 137 call_netdevice_notifiers(event, br->dev); 138 break; 139 } 140 141 if (event != NETDEV_UNREGISTER) 142 br_vlan_port_event(p, event); 143 144 /* Events that may cause spanning tree to refresh */ 145 if (!notified && (event == NETDEV_CHANGEADDR || event == NETDEV_UP || 146 event == NETDEV_CHANGE || event == NETDEV_DOWN)) 147 br_ifinfo_notify(RTM_NEWLINK, NULL, p); 148 149 return NOTIFY_DONE; 150 } 151 152 static struct notifier_block br_device_notifier = { 153 .notifier_call = br_device_event 154 }; 155 156 /* called with RTNL or RCU */ 157 static int br_switchdev_event(struct notifier_block *unused, 158 unsigned long event, void *ptr) 159 { 160 struct net_device *dev = switchdev_notifier_info_to_dev(ptr); 161 struct net_bridge_port *p; 162 struct net_bridge *br; 163 struct switchdev_notifier_fdb_info *fdb_info; 164 int err = NOTIFY_DONE; 165 166 p = br_port_get_rtnl_rcu(dev); 167 if (!p) 168 goto out; 169 170 br = p->br; 171 172 switch (event) { 173 case SWITCHDEV_FDB_ADD_TO_BRIDGE: 174 fdb_info = ptr; 175 err = br_fdb_external_learn_add(br, p, fdb_info->addr, 176 fdb_info->vid, 177 fdb_info->locked, false); 178 if (err) { 179 err = notifier_from_errno(err); 180 break; 181 } 182 br_fdb_offloaded_set(br, p, fdb_info->addr, 183 fdb_info->vid, fdb_info->offloaded); 184 break; 185 case SWITCHDEV_FDB_DEL_TO_BRIDGE: 186 fdb_info = ptr; 187 err = br_fdb_external_learn_del(br, p, fdb_info->addr, 188 fdb_info->vid, false); 189 if (err) 190 err = notifier_from_errno(err); 191 break; 192 case SWITCHDEV_FDB_OFFLOADED: 193 fdb_info = ptr; 194 br_fdb_offloaded_set(br, p, fdb_info->addr, 195 fdb_info->vid, fdb_info->offloaded); 196 break; 197 case SWITCHDEV_FDB_FLUSH_TO_BRIDGE: 198 fdb_info = ptr; 199 /* Don't delete static entries */ 200 br_fdb_delete_by_port(br, p, fdb_info->vid, 0); 201 break; 202 } 203 204 out: 205 return err; 206 } 207 208 static struct notifier_block br_switchdev_notifier = { 209 .notifier_call = br_switchdev_event, 210 }; 211 212 /* called under rtnl_mutex */ 213 static int br_switchdev_blocking_event(struct notifier_block *nb, 214 unsigned long event, void *ptr) 215 { 216 struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr); 217 struct net_device *dev = switchdev_notifier_info_to_dev(ptr); 218 struct switchdev_notifier_brport_info *brport_info; 219 const struct switchdev_brport *b; 220 struct net_bridge_port *p; 221 int err = NOTIFY_DONE; 222 223 p = br_port_get_rtnl(dev); 224 if (!p) 225 goto out; 226 227 switch (event) { 228 case SWITCHDEV_BRPORT_OFFLOADED: 229 brport_info = ptr; 230 b = &brport_info->brport; 231 232 err = br_switchdev_port_offload(p, b->dev, b->ctx, 233 b->atomic_nb, b->blocking_nb, 234 b->tx_fwd_offload, extack); 235 err = notifier_from_errno(err); 236 break; 237 case SWITCHDEV_BRPORT_UNOFFLOADED: 238 brport_info = ptr; 239 b = &brport_info->brport; 240 241 br_switchdev_port_unoffload(p, b->ctx, b->atomic_nb, 242 b->blocking_nb); 243 break; 244 case SWITCHDEV_BRPORT_REPLAY: 245 brport_info = ptr; 246 b = &brport_info->brport; 247 248 err = br_switchdev_port_replay(p, b->dev, b->ctx, b->atomic_nb, 249 b->blocking_nb, extack); 250 err = notifier_from_errno(err); 251 break; 252 } 253 254 out: 255 return err; 256 } 257 258 static struct notifier_block br_switchdev_blocking_notifier = { 259 .notifier_call = br_switchdev_blocking_event, 260 }; 261 262 /* br_boolopt_toggle - change user-controlled boolean option 263 * 264 * @br: bridge device 265 * @opt: id of the option to change 266 * @on: new option value 267 * @extack: extack for error messages 268 * 269 * Changes the value of the respective boolean option to @on taking care of 270 * any internal option value mapping and configuration. 271 */ 272 int br_boolopt_toggle(struct net_bridge *br, enum br_boolopt_id opt, bool on, 273 struct netlink_ext_ack *extack) 274 { 275 int err = 0; 276 277 switch (opt) { 278 case BR_BOOLOPT_NO_LL_LEARN: 279 br_opt_toggle(br, BROPT_NO_LL_LEARN, on); 280 break; 281 case BR_BOOLOPT_MCAST_VLAN_SNOOPING: 282 err = br_multicast_toggle_vlan_snooping(br, on, extack); 283 break; 284 case BR_BOOLOPT_MST_ENABLE: 285 err = br_mst_set_enabled(br, on, extack); 286 break; 287 default: 288 /* shouldn't be called with unsupported options */ 289 WARN_ON(1); 290 break; 291 } 292 293 return err; 294 } 295 296 int br_boolopt_get(const struct net_bridge *br, enum br_boolopt_id opt) 297 { 298 switch (opt) { 299 case BR_BOOLOPT_NO_LL_LEARN: 300 return br_opt_get(br, BROPT_NO_LL_LEARN); 301 case BR_BOOLOPT_MCAST_VLAN_SNOOPING: 302 return br_opt_get(br, BROPT_MCAST_VLAN_SNOOPING_ENABLED); 303 case BR_BOOLOPT_MST_ENABLE: 304 return br_opt_get(br, BROPT_MST_ENABLED); 305 default: 306 /* shouldn't be called with unsupported options */ 307 WARN_ON(1); 308 break; 309 } 310 311 return 0; 312 } 313 314 int br_boolopt_multi_toggle(struct net_bridge *br, 315 struct br_boolopt_multi *bm, 316 struct netlink_ext_ack *extack) 317 { 318 unsigned long bitmap = bm->optmask; 319 int err = 0; 320 int opt_id; 321 322 for_each_set_bit(opt_id, &bitmap, BR_BOOLOPT_MAX) { 323 bool on = !!(bm->optval & BIT(opt_id)); 324 325 err = br_boolopt_toggle(br, opt_id, on, extack); 326 if (err) { 327 br_debug(br, "boolopt multi-toggle error: option: %d current: %d new: %d error: %d\n", 328 opt_id, br_boolopt_get(br, opt_id), on, err); 329 break; 330 } 331 } 332 333 return err; 334 } 335 336 void br_boolopt_multi_get(const struct net_bridge *br, 337 struct br_boolopt_multi *bm) 338 { 339 u32 optval = 0; 340 int opt_id; 341 342 for (opt_id = 0; opt_id < BR_BOOLOPT_MAX; opt_id++) 343 optval |= (br_boolopt_get(br, opt_id) << opt_id); 344 345 bm->optval = optval; 346 bm->optmask = GENMASK((BR_BOOLOPT_MAX - 1), 0); 347 } 348 349 /* private bridge options, controlled by the kernel */ 350 void br_opt_toggle(struct net_bridge *br, enum net_bridge_opts opt, bool on) 351 { 352 bool cur = !!br_opt_get(br, opt); 353 354 br_debug(br, "toggle option: %d state: %d -> %d\n", 355 opt, cur, on); 356 357 if (cur == on) 358 return; 359 360 if (on) 361 set_bit(opt, &br->options); 362 else 363 clear_bit(opt, &br->options); 364 } 365 366 static void __net_exit br_net_exit_batch_rtnl(struct list_head *net_list, 367 struct list_head *dev_to_kill) 368 { 369 struct net_device *dev; 370 struct net *net; 371 372 ASSERT_RTNL(); 373 list_for_each_entry(net, net_list, exit_list) 374 for_each_netdev(net, dev) 375 if (netif_is_bridge_master(dev)) 376 br_dev_delete(dev, dev_to_kill); 377 } 378 379 static struct pernet_operations br_net_ops = { 380 .exit_batch_rtnl = br_net_exit_batch_rtnl, 381 }; 382 383 static const struct stp_proto br_stp_proto = { 384 .rcv = br_stp_rcv, 385 }; 386 387 static int __init br_init(void) 388 { 389 int err; 390 391 BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > sizeof_field(struct sk_buff, cb)); 392 393 err = stp_proto_register(&br_stp_proto); 394 if (err < 0) { 395 pr_err("bridge: can't register sap for STP\n"); 396 return err; 397 } 398 399 err = br_fdb_init(); 400 if (err) 401 goto err_out; 402 403 err = register_pernet_subsys(&br_net_ops); 404 if (err) 405 goto err_out1; 406 407 err = br_nf_core_init(); 408 if (err) 409 goto err_out2; 410 411 err = register_netdevice_notifier(&br_device_notifier); 412 if (err) 413 goto err_out3; 414 415 err = register_switchdev_notifier(&br_switchdev_notifier); 416 if (err) 417 goto err_out4; 418 419 err = register_switchdev_blocking_notifier(&br_switchdev_blocking_notifier); 420 if (err) 421 goto err_out5; 422 423 err = br_netlink_init(); 424 if (err) 425 goto err_out6; 426 427 brioctl_set(br_ioctl_stub); 428 429 #if IS_ENABLED(CONFIG_ATM_LANE) 430 br_fdb_test_addr_hook = br_fdb_test_addr; 431 #endif 432 433 #if IS_MODULE(CONFIG_BRIDGE_NETFILTER) 434 pr_info("bridge: filtering via arp/ip/ip6tables is no longer available " 435 "by default. Update your scripts to load br_netfilter if you " 436 "need this.\n"); 437 #endif 438 439 return 0; 440 441 err_out6: 442 unregister_switchdev_blocking_notifier(&br_switchdev_blocking_notifier); 443 err_out5: 444 unregister_switchdev_notifier(&br_switchdev_notifier); 445 err_out4: 446 unregister_netdevice_notifier(&br_device_notifier); 447 err_out3: 448 br_nf_core_fini(); 449 err_out2: 450 unregister_pernet_subsys(&br_net_ops); 451 err_out1: 452 br_fdb_fini(); 453 err_out: 454 stp_proto_unregister(&br_stp_proto); 455 return err; 456 } 457 458 static void __exit br_deinit(void) 459 { 460 stp_proto_unregister(&br_stp_proto); 461 br_netlink_fini(); 462 unregister_switchdev_blocking_notifier(&br_switchdev_blocking_notifier); 463 unregister_switchdev_notifier(&br_switchdev_notifier); 464 unregister_netdevice_notifier(&br_device_notifier); 465 brioctl_set(NULL); 466 unregister_pernet_subsys(&br_net_ops); 467 468 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 469 470 br_nf_core_fini(); 471 #if IS_ENABLED(CONFIG_ATM_LANE) 472 br_fdb_test_addr_hook = NULL; 473 #endif 474 br_fdb_fini(); 475 } 476 477 module_init(br_init) 478 module_exit(br_deinit) 479 MODULE_LICENSE("GPL"); 480 MODULE_VERSION(BR_VERSION); 481 MODULE_ALIAS_RTNL_LINK("bridge"); 482 MODULE_DESCRIPTION("Ethernet bridge driver"); 483