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