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 changed_addr; 38 int err; 39 40 /* register of bridge completed, add sysfs entries */ 41 if ((dev->priv_flags & IFF_EBRIDGE) && event == NETDEV_REGISTER) { 42 br_sysfs_addbr(dev); 43 return NOTIFY_DONE; 44 } 45 46 /* not a port of a bridge */ 47 p = br_port_get_rtnl(dev); 48 if (!p) 49 return NOTIFY_DONE; 50 51 br = p->br; 52 53 switch (event) { 54 case NETDEV_CHANGEMTU: 55 dev_set_mtu(br->dev, br_min_mtu(br)); 56 break; 57 58 case NETDEV_CHANGEADDR: 59 spin_lock_bh(&br->lock); 60 br_fdb_changeaddr(p, dev->dev_addr); 61 changed_addr = br_stp_recalculate_bridge_id(br); 62 spin_unlock_bh(&br->lock); 63 64 if (changed_addr) 65 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev); 66 67 break; 68 69 case NETDEV_CHANGE: 70 br_port_carrier_check(p); 71 break; 72 73 case NETDEV_FEAT_CHANGE: 74 netdev_update_features(br->dev); 75 break; 76 77 case NETDEV_DOWN: 78 spin_lock_bh(&br->lock); 79 if (br->dev->flags & IFF_UP) 80 br_stp_disable_port(p); 81 spin_unlock_bh(&br->lock); 82 break; 83 84 case NETDEV_UP: 85 if (netif_running(br->dev) && netif_oper_up(dev)) { 86 spin_lock_bh(&br->lock); 87 br_stp_enable_port(p); 88 spin_unlock_bh(&br->lock); 89 } 90 break; 91 92 case NETDEV_UNREGISTER: 93 br_del_if(br, dev); 94 break; 95 96 case NETDEV_CHANGENAME: 97 err = br_sysfs_renameif(p); 98 if (err) 99 return notifier_from_errno(err); 100 break; 101 102 case NETDEV_PRE_TYPE_CHANGE: 103 /* Forbid underlaying device to change its type. */ 104 return NOTIFY_BAD; 105 106 case NETDEV_RESEND_IGMP: 107 /* Propagate to master device */ 108 call_netdevice_notifiers(event, br->dev); 109 break; 110 } 111 112 /* Events that may cause spanning tree to refresh */ 113 if (event == NETDEV_CHANGEADDR || event == NETDEV_UP || 114 event == NETDEV_CHANGE || event == NETDEV_DOWN) 115 br_ifinfo_notify(RTM_NEWLINK, p); 116 117 return NOTIFY_DONE; 118 } 119 120 static struct notifier_block br_device_notifier = { 121 .notifier_call = br_device_event 122 }; 123 124 static int br_netdev_switch_event(struct notifier_block *unused, 125 unsigned long event, void *ptr) 126 { 127 struct net_device *dev = netdev_switch_notifier_info_to_dev(ptr); 128 struct net_bridge_port *p; 129 struct net_bridge *br; 130 struct netdev_switch_notifier_fdb_info *fdb_info; 131 int err = NOTIFY_DONE; 132 133 rtnl_lock(); 134 p = br_port_get_rtnl(dev); 135 if (!p) 136 goto out; 137 138 br = p->br; 139 140 switch (event) { 141 case NETDEV_SWITCH_FDB_ADD: 142 fdb_info = ptr; 143 err = br_fdb_external_learn_add(br, p, fdb_info->addr, 144 fdb_info->vid); 145 if (err) 146 err = notifier_from_errno(err); 147 break; 148 case NETDEV_SWITCH_FDB_DEL: 149 fdb_info = ptr; 150 err = br_fdb_external_learn_del(br, p, fdb_info->addr, 151 fdb_info->vid); 152 if (err) 153 err = notifier_from_errno(err); 154 break; 155 } 156 157 out: 158 rtnl_unlock(); 159 return err; 160 } 161 162 static struct notifier_block br_netdev_switch_notifier = { 163 .notifier_call = br_netdev_switch_event, 164 }; 165 166 static void __net_exit br_net_exit(struct net *net) 167 { 168 struct net_device *dev; 169 LIST_HEAD(list); 170 171 rtnl_lock(); 172 for_each_netdev(net, dev) 173 if (dev->priv_flags & IFF_EBRIDGE) 174 br_dev_delete(dev, &list); 175 176 unregister_netdevice_many(&list); 177 rtnl_unlock(); 178 179 } 180 181 static struct pernet_operations br_net_ops = { 182 .exit = br_net_exit, 183 }; 184 185 static const struct stp_proto br_stp_proto = { 186 .rcv = br_stp_rcv, 187 }; 188 189 static int __init br_init(void) 190 { 191 int err; 192 193 BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb)); 194 195 err = stp_proto_register(&br_stp_proto); 196 if (err < 0) { 197 pr_err("bridge: can't register sap for STP\n"); 198 return err; 199 } 200 201 err = br_fdb_init(); 202 if (err) 203 goto err_out; 204 205 err = register_pernet_subsys(&br_net_ops); 206 if (err) 207 goto err_out1; 208 209 err = br_nf_core_init(); 210 if (err) 211 goto err_out2; 212 213 err = register_netdevice_notifier(&br_device_notifier); 214 if (err) 215 goto err_out3; 216 217 err = register_netdev_switch_notifier(&br_netdev_switch_notifier); 218 if (err) 219 goto err_out4; 220 221 err = br_netlink_init(); 222 if (err) 223 goto err_out5; 224 225 brioctl_set(br_ioctl_deviceless_stub); 226 227 #if IS_ENABLED(CONFIG_ATM_LANE) 228 br_fdb_test_addr_hook = br_fdb_test_addr; 229 #endif 230 231 pr_info("bridge: automatic filtering via arp/ip/ip6tables has been " 232 "deprecated. Update your scripts to load br_netfilter if you " 233 "need this.\n"); 234 235 return 0; 236 237 err_out5: 238 unregister_netdev_switch_notifier(&br_netdev_switch_notifier); 239 err_out4: 240 unregister_netdevice_notifier(&br_device_notifier); 241 err_out3: 242 br_nf_core_fini(); 243 err_out2: 244 unregister_pernet_subsys(&br_net_ops); 245 err_out1: 246 br_fdb_fini(); 247 err_out: 248 stp_proto_unregister(&br_stp_proto); 249 return err; 250 } 251 252 static void __exit br_deinit(void) 253 { 254 stp_proto_unregister(&br_stp_proto); 255 br_netlink_fini(); 256 unregister_netdev_switch_notifier(&br_netdev_switch_notifier); 257 unregister_netdevice_notifier(&br_device_notifier); 258 brioctl_set(NULL); 259 unregister_pernet_subsys(&br_net_ops); 260 261 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 262 263 br_nf_core_fini(); 264 #if IS_ENABLED(CONFIG_ATM_LANE) 265 br_fdb_test_addr_hook = NULL; 266 #endif 267 br_fdb_fini(); 268 } 269 270 module_init(br_init) 271 module_exit(br_deinit) 272 MODULE_LICENSE("GPL"); 273 MODULE_VERSION(BR_VERSION); 274 MODULE_ALIAS_RTNL_LINK("bridge"); 275