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 void br_opt_toggle(struct net_bridge *br, enum net_bridge_opts opt, bool on) 179 { 180 bool cur = !!br_opt_get(br, opt); 181 182 br_debug(br, "toggle option: %d state: %d -> %d\n", 183 opt, cur, on); 184 185 if (cur == on) 186 return; 187 188 if (on) 189 set_bit(opt, &br->options); 190 else 191 clear_bit(opt, &br->options); 192 } 193 194 static void __net_exit br_net_exit(struct net *net) 195 { 196 struct net_device *dev; 197 LIST_HEAD(list); 198 199 rtnl_lock(); 200 for_each_netdev(net, dev) 201 if (dev->priv_flags & IFF_EBRIDGE) 202 br_dev_delete(dev, &list); 203 204 unregister_netdevice_many(&list); 205 rtnl_unlock(); 206 207 } 208 209 static struct pernet_operations br_net_ops = { 210 .exit = br_net_exit, 211 }; 212 213 static const struct stp_proto br_stp_proto = { 214 .rcv = br_stp_rcv, 215 }; 216 217 static int __init br_init(void) 218 { 219 int err; 220 221 BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb)); 222 223 err = stp_proto_register(&br_stp_proto); 224 if (err < 0) { 225 pr_err("bridge: can't register sap for STP\n"); 226 return err; 227 } 228 229 err = br_fdb_init(); 230 if (err) 231 goto err_out; 232 233 err = register_pernet_subsys(&br_net_ops); 234 if (err) 235 goto err_out1; 236 237 err = br_nf_core_init(); 238 if (err) 239 goto err_out2; 240 241 err = register_netdevice_notifier(&br_device_notifier); 242 if (err) 243 goto err_out3; 244 245 err = register_switchdev_notifier(&br_switchdev_notifier); 246 if (err) 247 goto err_out4; 248 249 err = br_netlink_init(); 250 if (err) 251 goto err_out5; 252 253 brioctl_set(br_ioctl_deviceless_stub); 254 255 #if IS_ENABLED(CONFIG_ATM_LANE) 256 br_fdb_test_addr_hook = br_fdb_test_addr; 257 #endif 258 259 #if IS_MODULE(CONFIG_BRIDGE_NETFILTER) 260 pr_info("bridge: filtering via arp/ip/ip6tables is no longer available " 261 "by default. Update your scripts to load br_netfilter if you " 262 "need this.\n"); 263 #endif 264 265 return 0; 266 267 err_out5: 268 unregister_switchdev_notifier(&br_switchdev_notifier); 269 err_out4: 270 unregister_netdevice_notifier(&br_device_notifier); 271 err_out3: 272 br_nf_core_fini(); 273 err_out2: 274 unregister_pernet_subsys(&br_net_ops); 275 err_out1: 276 br_fdb_fini(); 277 err_out: 278 stp_proto_unregister(&br_stp_proto); 279 return err; 280 } 281 282 static void __exit br_deinit(void) 283 { 284 stp_proto_unregister(&br_stp_proto); 285 br_netlink_fini(); 286 unregister_switchdev_notifier(&br_switchdev_notifier); 287 unregister_netdevice_notifier(&br_device_notifier); 288 brioctl_set(NULL); 289 unregister_pernet_subsys(&br_net_ops); 290 291 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 292 293 br_nf_core_fini(); 294 #if IS_ENABLED(CONFIG_ATM_LANE) 295 br_fdb_test_addr_hook = NULL; 296 #endif 297 br_fdb_fini(); 298 } 299 300 module_init(br_init) 301 module_exit(br_deinit) 302 MODULE_LICENSE("GPL"); 303 MODULE_VERSION(BR_VERSION); 304 MODULE_ALIAS_RTNL_LINK("bridge"); 305