1 /* 2 * Device handling code 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/kernel.h> 15 #include <linux/netdevice.h> 16 #include <linux/netpoll.h> 17 #include <linux/etherdevice.h> 18 #include <linux/ethtool.h> 19 #include <linux/list.h> 20 #include <linux/netfilter_bridge.h> 21 22 #include <asm/uaccess.h> 23 #include "br_private.h" 24 25 /* net device transmit always called with BH disabled */ 26 netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev) 27 { 28 struct net_bridge *br = netdev_priv(dev); 29 const unsigned char *dest = skb->data; 30 struct net_bridge_fdb_entry *dst; 31 struct net_bridge_mdb_entry *mdst; 32 struct br_cpu_netstats *brstats = this_cpu_ptr(br->stats); 33 u16 vid = 0; 34 35 rcu_read_lock(); 36 #ifdef CONFIG_BRIDGE_NETFILTER 37 if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) { 38 br_nf_pre_routing_finish_bridge_slow(skb); 39 rcu_read_unlock(); 40 return NETDEV_TX_OK; 41 } 42 #endif 43 44 u64_stats_update_begin(&brstats->syncp); 45 brstats->tx_packets++; 46 brstats->tx_bytes += skb->len; 47 u64_stats_update_end(&brstats->syncp); 48 49 if (!br_allowed_ingress(br, br_get_vlan_info(br), skb, &vid)) 50 goto out; 51 52 BR_INPUT_SKB_CB(skb)->brdev = dev; 53 54 skb_reset_mac_header(skb); 55 skb_pull(skb, ETH_HLEN); 56 57 if (is_broadcast_ether_addr(dest)) 58 br_flood_deliver(br, skb); 59 else if (is_multicast_ether_addr(dest)) { 60 if (unlikely(netpoll_tx_running(dev))) { 61 br_flood_deliver(br, skb); 62 goto out; 63 } 64 if (br_multicast_rcv(br, NULL, skb)) { 65 kfree_skb(skb); 66 goto out; 67 } 68 69 mdst = br_mdb_get(br, skb); 70 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) 71 br_multicast_deliver(mdst, skb); 72 else 73 br_flood_deliver(br, skb); 74 } else if ((dst = __br_fdb_get(br, dest, vid)) != NULL) 75 br_deliver(dst->dst, skb); 76 else 77 br_flood_deliver(br, skb); 78 79 out: 80 rcu_read_unlock(); 81 return NETDEV_TX_OK; 82 } 83 84 static int br_dev_init(struct net_device *dev) 85 { 86 struct net_bridge *br = netdev_priv(dev); 87 88 br->stats = alloc_percpu(struct br_cpu_netstats); 89 if (!br->stats) 90 return -ENOMEM; 91 92 return 0; 93 } 94 95 static int br_dev_open(struct net_device *dev) 96 { 97 struct net_bridge *br = netdev_priv(dev); 98 99 netdev_update_features(dev); 100 netif_start_queue(dev); 101 br_stp_enable_bridge(br); 102 br_multicast_open(br); 103 104 return 0; 105 } 106 107 static void br_dev_set_multicast_list(struct net_device *dev) 108 { 109 } 110 111 static int br_dev_stop(struct net_device *dev) 112 { 113 struct net_bridge *br = netdev_priv(dev); 114 115 br_stp_disable_bridge(br); 116 br_multicast_stop(br); 117 118 netif_stop_queue(dev); 119 120 return 0; 121 } 122 123 static struct rtnl_link_stats64 *br_get_stats64(struct net_device *dev, 124 struct rtnl_link_stats64 *stats) 125 { 126 struct net_bridge *br = netdev_priv(dev); 127 struct br_cpu_netstats tmp, sum = { 0 }; 128 unsigned int cpu; 129 130 for_each_possible_cpu(cpu) { 131 unsigned int start; 132 const struct br_cpu_netstats *bstats 133 = per_cpu_ptr(br->stats, cpu); 134 do { 135 start = u64_stats_fetch_begin_bh(&bstats->syncp); 136 memcpy(&tmp, bstats, sizeof(tmp)); 137 } while (u64_stats_fetch_retry_bh(&bstats->syncp, start)); 138 sum.tx_bytes += tmp.tx_bytes; 139 sum.tx_packets += tmp.tx_packets; 140 sum.rx_bytes += tmp.rx_bytes; 141 sum.rx_packets += tmp.rx_packets; 142 } 143 144 stats->tx_bytes = sum.tx_bytes; 145 stats->tx_packets = sum.tx_packets; 146 stats->rx_bytes = sum.rx_bytes; 147 stats->rx_packets = sum.rx_packets; 148 149 return stats; 150 } 151 152 static int br_change_mtu(struct net_device *dev, int new_mtu) 153 { 154 struct net_bridge *br = netdev_priv(dev); 155 if (new_mtu < 68 || new_mtu > br_min_mtu(br)) 156 return -EINVAL; 157 158 dev->mtu = new_mtu; 159 160 #ifdef CONFIG_BRIDGE_NETFILTER 161 /* remember the MTU in the rtable for PMTU */ 162 dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu); 163 #endif 164 165 return 0; 166 } 167 168 /* Allow setting mac address to any valid ethernet address. */ 169 static int br_set_mac_address(struct net_device *dev, void *p) 170 { 171 struct net_bridge *br = netdev_priv(dev); 172 struct sockaddr *addr = p; 173 174 if (!is_valid_ether_addr(addr->sa_data)) 175 return -EADDRNOTAVAIL; 176 177 spin_lock_bh(&br->lock); 178 if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) { 179 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); 180 br_fdb_change_mac_address(br, addr->sa_data); 181 br_stp_change_bridge_id(br, addr->sa_data); 182 } 183 spin_unlock_bh(&br->lock); 184 185 return 0; 186 } 187 188 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) 189 { 190 strlcpy(info->driver, "bridge", sizeof(info->driver)); 191 strlcpy(info->version, BR_VERSION, sizeof(info->version)); 192 strlcpy(info->fw_version, "N/A", sizeof(info->fw_version)); 193 strlcpy(info->bus_info, "N/A", sizeof(info->bus_info)); 194 } 195 196 static netdev_features_t br_fix_features(struct net_device *dev, 197 netdev_features_t features) 198 { 199 struct net_bridge *br = netdev_priv(dev); 200 201 return br_features_recompute(br, features); 202 } 203 204 #ifdef CONFIG_NET_POLL_CONTROLLER 205 static void br_poll_controller(struct net_device *br_dev) 206 { 207 } 208 209 static void br_netpoll_cleanup(struct net_device *dev) 210 { 211 struct net_bridge *br = netdev_priv(dev); 212 struct net_bridge_port *p; 213 214 list_for_each_entry(p, &br->port_list, list) 215 br_netpoll_disable(p); 216 } 217 218 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni, 219 gfp_t gfp) 220 { 221 struct net_bridge *br = netdev_priv(dev); 222 struct net_bridge_port *p; 223 int err = 0; 224 225 list_for_each_entry(p, &br->port_list, list) { 226 if (!p->dev) 227 continue; 228 err = br_netpoll_enable(p, gfp); 229 if (err) 230 goto fail; 231 } 232 233 out: 234 return err; 235 236 fail: 237 br_netpoll_cleanup(dev); 238 goto out; 239 } 240 241 int br_netpoll_enable(struct net_bridge_port *p, gfp_t gfp) 242 { 243 struct netpoll *np; 244 int err = 0; 245 246 np = kzalloc(sizeof(*p->np), gfp); 247 err = -ENOMEM; 248 if (!np) 249 goto out; 250 251 err = __netpoll_setup(np, p->dev, gfp); 252 if (err) { 253 kfree(np); 254 goto out; 255 } 256 257 p->np = np; 258 259 out: 260 return err; 261 } 262 263 void br_netpoll_disable(struct net_bridge_port *p) 264 { 265 struct netpoll *np = p->np; 266 267 if (!np) 268 return; 269 270 p->np = NULL; 271 272 __netpoll_free_async(np); 273 } 274 275 #endif 276 277 static int br_add_slave(struct net_device *dev, struct net_device *slave_dev) 278 279 { 280 struct net_bridge *br = netdev_priv(dev); 281 282 return br_add_if(br, slave_dev); 283 } 284 285 static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) 286 { 287 struct net_bridge *br = netdev_priv(dev); 288 289 return br_del_if(br, slave_dev); 290 } 291 292 static const struct ethtool_ops br_ethtool_ops = { 293 .get_drvinfo = br_getinfo, 294 .get_link = ethtool_op_get_link, 295 }; 296 297 static const struct net_device_ops br_netdev_ops = { 298 .ndo_open = br_dev_open, 299 .ndo_stop = br_dev_stop, 300 .ndo_init = br_dev_init, 301 .ndo_start_xmit = br_dev_xmit, 302 .ndo_get_stats64 = br_get_stats64, 303 .ndo_set_mac_address = br_set_mac_address, 304 .ndo_set_rx_mode = br_dev_set_multicast_list, 305 .ndo_change_mtu = br_change_mtu, 306 .ndo_do_ioctl = br_dev_ioctl, 307 #ifdef CONFIG_NET_POLL_CONTROLLER 308 .ndo_netpoll_setup = br_netpoll_setup, 309 .ndo_netpoll_cleanup = br_netpoll_cleanup, 310 .ndo_poll_controller = br_poll_controller, 311 #endif 312 .ndo_add_slave = br_add_slave, 313 .ndo_del_slave = br_del_slave, 314 .ndo_fix_features = br_fix_features, 315 .ndo_fdb_add = br_fdb_add, 316 .ndo_fdb_del = br_fdb_delete, 317 .ndo_fdb_dump = br_fdb_dump, 318 .ndo_bridge_getlink = br_getlink, 319 .ndo_bridge_setlink = br_setlink, 320 .ndo_bridge_dellink = br_dellink, 321 }; 322 323 static void br_dev_free(struct net_device *dev) 324 { 325 struct net_bridge *br = netdev_priv(dev); 326 327 free_percpu(br->stats); 328 free_netdev(dev); 329 } 330 331 static struct device_type br_type = { 332 .name = "bridge", 333 }; 334 335 void br_dev_setup(struct net_device *dev) 336 { 337 struct net_bridge *br = netdev_priv(dev); 338 339 eth_hw_addr_random(dev); 340 ether_setup(dev); 341 342 dev->netdev_ops = &br_netdev_ops; 343 dev->destructor = br_dev_free; 344 SET_ETHTOOL_OPS(dev, &br_ethtool_ops); 345 SET_NETDEV_DEVTYPE(dev, &br_type); 346 dev->tx_queue_len = 0; 347 dev->priv_flags = IFF_EBRIDGE; 348 349 dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | 350 NETIF_F_GSO_MASK | NETIF_F_HW_CSUM | NETIF_F_LLTX | 351 NETIF_F_NETNS_LOCAL | NETIF_F_HW_VLAN_TX; 352 dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | 353 NETIF_F_GSO_MASK | NETIF_F_HW_CSUM | 354 NETIF_F_HW_VLAN_TX; 355 356 br->dev = dev; 357 spin_lock_init(&br->lock); 358 INIT_LIST_HEAD(&br->port_list); 359 spin_lock_init(&br->hash_lock); 360 361 br->bridge_id.prio[0] = 0x80; 362 br->bridge_id.prio[1] = 0x00; 363 364 memcpy(br->group_addr, eth_reserved_addr_base, ETH_ALEN); 365 366 br->stp_enabled = BR_NO_STP; 367 br->group_fwd_mask = BR_GROUPFWD_DEFAULT; 368 369 br->designated_root = br->bridge_id; 370 br->bridge_max_age = br->max_age = 20 * HZ; 371 br->bridge_hello_time = br->hello_time = 2 * HZ; 372 br->bridge_forward_delay = br->forward_delay = 15 * HZ; 373 br->ageing_time = 300 * HZ; 374 375 br_netfilter_rtable_init(br); 376 br_stp_timer_init(br); 377 br_multicast_init(br); 378 } 379