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 */ 26netdev_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 if (!br_allowed_ingress(br, br_get_vlan_info(br), skb, &vid)) 45 goto out; 46 47 BR_INPUT_SKB_CB(skb)->brdev = dev; 48 49 skb_reset_mac_header(skb); 50 skb_pull(skb, ETH_HLEN); 51 52 u64_stats_update_begin(&brstats->syncp); 53 brstats->tx_packets++; 54 /* Exclude ETH_HLEN from byte stats for consistency with Rx chain */ 55 brstats->tx_bytes += skb->len; 56 u64_stats_update_end(&brstats->syncp); 57 58 if (is_broadcast_ether_addr(dest)) 59 br_flood_deliver(br, skb); 60 else if (is_multicast_ether_addr(dest)) { 61 if (unlikely(netpoll_tx_running(dev))) { 62 br_flood_deliver(br, skb); 63 goto out; 64 } 65 if (br_multicast_rcv(br, NULL, skb)) { 66 kfree_skb(skb); 67 goto out; 68 } 69 70 mdst = br_mdb_get(br, skb, vid); 71 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) 72 br_multicast_deliver(mdst, skb); 73 else 74 br_flood_deliver(br, skb); 75 } else if ((dst = __br_fdb_get(br, dest, vid)) != NULL) 76 br_deliver(dst->dst, skb); 77 else 78 br_flood_deliver(br, skb); 79 80out: 81 rcu_read_unlock(); 82 return NETDEV_TX_OK; 83} 84 85static int br_dev_init(struct net_device *dev) 86{ 87 struct net_bridge *br = netdev_priv(dev); 88 89 br->stats = alloc_percpu(struct br_cpu_netstats); 90 if (!br->stats) 91 return -ENOMEM; 92 93 return 0; 94} 95 96static int br_dev_open(struct net_device *dev) 97{ 98 struct net_bridge *br = netdev_priv(dev); 99 100 netdev_update_features(dev); 101 netif_start_queue(dev); 102 br_stp_enable_bridge(br); 103 br_multicast_open(br); 104 105 return 0; 106} 107 108static void br_dev_set_multicast_list(struct net_device *dev) 109{ 110} 111 112static int br_dev_stop(struct net_device *dev) 113{ 114 struct net_bridge *br = netdev_priv(dev); 115 116 br_stp_disable_bridge(br); 117 br_multicast_stop(br); 118 119 netif_stop_queue(dev); 120 121 return 0; 122} 123 124static struct rtnl_link_stats64 *br_get_stats64(struct net_device *dev, 125 struct rtnl_link_stats64 *stats) 126{ 127 struct net_bridge *br = netdev_priv(dev); 128 struct br_cpu_netstats tmp, sum = { 0 }; 129 unsigned int cpu; 130 131 for_each_possible_cpu(cpu) { 132 unsigned int start; 133 const struct br_cpu_netstats *bstats 134 = per_cpu_ptr(br->stats, cpu); 135 do { 136 start = u64_stats_fetch_begin_bh(&bstats->syncp); 137 memcpy(&tmp, bstats, sizeof(tmp)); 138 } while (u64_stats_fetch_retry_bh(&bstats->syncp, start)); 139 sum.tx_bytes += tmp.tx_bytes; 140 sum.tx_packets += tmp.tx_packets; 141 sum.rx_bytes += tmp.rx_bytes; 142 sum.rx_packets += tmp.rx_packets; 143 } 144 145 stats->tx_bytes = sum.tx_bytes; 146 stats->tx_packets = sum.tx_packets; 147 stats->rx_bytes = sum.rx_bytes; 148 stats->rx_packets = sum.rx_packets; 149 150 return stats; 151} 152 153static int br_change_mtu(struct net_device *dev, int new_mtu) 154{ 155 struct net_bridge *br = netdev_priv(dev); 156 if (new_mtu < 68 || new_mtu > br_min_mtu(br)) 157 return -EINVAL; 158 159 dev->mtu = new_mtu; 160 161#ifdef CONFIG_BRIDGE_NETFILTER 162 /* remember the MTU in the rtable for PMTU */ 163 dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu); 164#endif 165 166 return 0; 167} 168 169/* Allow setting mac address to any valid ethernet address. */ 170static int br_set_mac_address(struct net_device *dev, void *p) 171{ 172 struct net_bridge *br = netdev_priv(dev); 173 struct sockaddr *addr = p; 174 175 if (!is_valid_ether_addr(addr->sa_data)) 176 return -EADDRNOTAVAIL; 177 178 spin_lock_bh(&br->lock); 179 if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) { 180 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); 181 br_fdb_change_mac_address(br, addr->sa_data); 182 br_stp_change_bridge_id(br, addr->sa_data); 183 } 184 spin_unlock_bh(&br->lock); 185 186 return 0; 187} 188 189static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) 190{ 191 strlcpy(info->driver, "bridge", sizeof(info->driver)); 192 strlcpy(info->version, BR_VERSION, sizeof(info->version)); 193 strlcpy(info->fw_version, "N/A", sizeof(info->fw_version)); 194 strlcpy(info->bus_info, "N/A", sizeof(info->bus_info)); 195} 196 197static netdev_features_t br_fix_features(struct net_device *dev, 198 netdev_features_t features) 199{ 200 struct net_bridge *br = netdev_priv(dev); 201 202 return br_features_recompute(br, features); 203} 204 205#ifdef CONFIG_NET_POLL_CONTROLLER 206static void br_poll_controller(struct net_device *br_dev) 207{ 208} 209 210static void br_netpoll_cleanup(struct net_device *dev) 211{ 212 struct net_bridge *br = netdev_priv(dev); 213 struct net_bridge_port *p; 214 215 list_for_each_entry(p, &br->port_list, list) 216 br_netpoll_disable(p); 217} 218 219static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni, 220 gfp_t gfp) 221{ 222 struct net_bridge *br = netdev_priv(dev); 223 struct net_bridge_port *p; 224 int err = 0; 225 226 list_for_each_entry(p, &br->port_list, list) { 227 if (!p->dev) 228 continue; 229 err = br_netpoll_enable(p, gfp); 230 if (err) 231 goto fail; 232 } 233 234out: 235 return err; 236 237fail: 238 br_netpoll_cleanup(dev); 239 goto out; 240} 241 242int br_netpoll_enable(struct net_bridge_port *p, gfp_t gfp) 243{ 244 struct netpoll *np; 245 int err = 0; 246 247 np = kzalloc(sizeof(*p->np), gfp); 248 err = -ENOMEM; 249 if (!np) 250 goto out; 251 252 err = __netpoll_setup(np, p->dev, gfp); 253 if (err) { 254 kfree(np); 255 goto out; 256 } 257 258 p->np = np; 259 260out: 261 return err; 262} 263 264void br_netpoll_disable(struct net_bridge_port *p) 265{ 266 struct netpoll *np = p->np; 267 268 if (!np) 269 return; 270 271 p->np = NULL; 272 273 __netpoll_free_async(np); 274} 275 276#endif 277 278static int br_add_slave(struct net_device *dev, struct net_device *slave_dev) 279 280{ 281 struct net_bridge *br = netdev_priv(dev); 282 283 return br_add_if(br, slave_dev); 284} 285 286static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) 287{ 288 struct net_bridge *br = netdev_priv(dev); 289 290 return br_del_if(br, slave_dev); 291} 292 293static const struct ethtool_ops br_ethtool_ops = { 294 .get_drvinfo = br_getinfo, 295 .get_link = ethtool_op_get_link, 296}; 297 298static const struct net_device_ops br_netdev_ops = { 299 .ndo_open = br_dev_open, 300 .ndo_stop = br_dev_stop, 301 .ndo_init = br_dev_init, 302 .ndo_start_xmit = br_dev_xmit, 303 .ndo_get_stats64 = br_get_stats64, 304 .ndo_set_mac_address = br_set_mac_address, 305 .ndo_set_rx_mode = br_dev_set_multicast_list, 306 .ndo_change_mtu = br_change_mtu, 307 .ndo_do_ioctl = br_dev_ioctl, 308#ifdef CONFIG_NET_POLL_CONTROLLER 309 .ndo_netpoll_setup = br_netpoll_setup, 310 .ndo_netpoll_cleanup = br_netpoll_cleanup, 311 .ndo_poll_controller = br_poll_controller, 312#endif 313 .ndo_add_slave = br_add_slave, 314 .ndo_del_slave = br_del_slave, 315 .ndo_fix_features = br_fix_features, 316 .ndo_fdb_add = br_fdb_add, 317 .ndo_fdb_del = br_fdb_delete, 318 .ndo_fdb_dump = br_fdb_dump, 319 .ndo_bridge_getlink = br_getlink, 320 .ndo_bridge_setlink = br_setlink, 321 .ndo_bridge_dellink = br_dellink, 322}; 323 324static void br_dev_free(struct net_device *dev) 325{ 326 struct net_bridge *br = netdev_priv(dev); 327 328 free_percpu(br->stats); 329 free_netdev(dev); 330} 331 332static struct device_type br_type = { 333 .name = "bridge", 334}; 335 336void br_dev_setup(struct net_device *dev) 337{ 338 struct net_bridge *br = netdev_priv(dev); 339 340 eth_hw_addr_random(dev); 341 ether_setup(dev); 342 343 dev->netdev_ops = &br_netdev_ops; 344 dev->destructor = br_dev_free; 345 SET_ETHTOOL_OPS(dev, &br_ethtool_ops); 346 SET_NETDEV_DEVTYPE(dev, &br_type); 347 dev->tx_queue_len = 0; 348 dev->priv_flags = IFF_EBRIDGE; 349 350 dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | 351 NETIF_F_GSO_MASK | NETIF_F_HW_CSUM | NETIF_F_LLTX | 352 NETIF_F_NETNS_LOCAL | NETIF_F_HW_VLAN_CTAG_TX; 353 dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | 354 NETIF_F_GSO_MASK | NETIF_F_HW_CSUM | 355 NETIF_F_HW_VLAN_CTAG_TX; 356 357 br->dev = dev; 358 spin_lock_init(&br->lock); 359 INIT_LIST_HEAD(&br->port_list); 360 spin_lock_init(&br->hash_lock); 361 362 br->bridge_id.prio[0] = 0x80; 363 br->bridge_id.prio[1] = 0x00; 364 365 memcpy(br->group_addr, eth_reserved_addr_base, ETH_ALEN); 366 367 br->stp_enabled = BR_NO_STP; 368 br->group_fwd_mask = BR_GROUPFWD_DEFAULT; 369 370 br->designated_root = br->bridge_id; 371 br->bridge_max_age = br->max_age = 20 * HZ; 372 br->bridge_hello_time = br->hello_time = 2 * HZ; 373 br->bridge_forward_delay = br->forward_delay = 15 * HZ; 374 br->ageing_time = 300 * HZ; 375 376 br_netfilter_rtable_init(br); 377 br_stp_timer_init(br); 378 br_multicast_init(br); 379} 380