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