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