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 34 #ifdef CONFIG_BRIDGE_NETFILTER 35 if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) { 36 br_nf_pre_routing_finish_bridge_slow(skb); 37 return NETDEV_TX_OK; 38 } 39 #endif 40 41 u64_stats_update_begin(&brstats->syncp); 42 brstats->tx_packets++; 43 brstats->tx_bytes += skb->len; 44 u64_stats_update_end(&brstats->syncp); 45 46 BR_INPUT_SKB_CB(skb)->brdev = dev; 47 48 skb_reset_mac_header(skb); 49 skb_pull(skb, ETH_HLEN); 50 51 rcu_read_lock(); 52 if (is_multicast_ether_addr(dest)) { 53 if (unlikely(netpoll_tx_running(dev))) { 54 br_flood_deliver(br, skb); 55 goto out; 56 } 57 if (br_multicast_rcv(br, NULL, skb)) { 58 kfree_skb(skb); 59 goto out; 60 } 61 62 mdst = br_mdb_get(br, skb); 63 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) 64 br_multicast_deliver(mdst, skb); 65 else 66 br_flood_deliver(br, skb); 67 } else if ((dst = __br_fdb_get(br, dest)) != NULL) 68 br_deliver(dst->dst, skb); 69 else 70 br_flood_deliver(br, skb); 71 72 out: 73 rcu_read_unlock(); 74 return NETDEV_TX_OK; 75 } 76 77 static int br_dev_open(struct net_device *dev) 78 { 79 struct net_bridge *br = netdev_priv(dev); 80 81 netif_carrier_off(dev); 82 83 br_features_recompute(br); 84 netif_start_queue(dev); 85 br_stp_enable_bridge(br); 86 br_multicast_open(br); 87 88 return 0; 89 } 90 91 static void br_dev_set_multicast_list(struct net_device *dev) 92 { 93 } 94 95 static int br_dev_stop(struct net_device *dev) 96 { 97 struct net_bridge *br = netdev_priv(dev); 98 99 netif_carrier_off(dev); 100 101 br_stp_disable_bridge(br); 102 br_multicast_stop(br); 103 104 netif_stop_queue(dev); 105 106 return 0; 107 } 108 109 static struct rtnl_link_stats64 *br_get_stats64(struct net_device *dev, 110 struct rtnl_link_stats64 *stats) 111 { 112 struct net_bridge *br = netdev_priv(dev); 113 struct br_cpu_netstats tmp, sum = { 0 }; 114 unsigned int cpu; 115 116 for_each_possible_cpu(cpu) { 117 unsigned int start; 118 const struct br_cpu_netstats *bstats 119 = per_cpu_ptr(br->stats, cpu); 120 do { 121 start = u64_stats_fetch_begin(&bstats->syncp); 122 memcpy(&tmp, bstats, sizeof(tmp)); 123 } while (u64_stats_fetch_retry(&bstats->syncp, start)); 124 sum.tx_bytes += tmp.tx_bytes; 125 sum.tx_packets += tmp.tx_packets; 126 sum.rx_bytes += tmp.rx_bytes; 127 sum.rx_packets += tmp.rx_packets; 128 } 129 130 stats->tx_bytes = sum.tx_bytes; 131 stats->tx_packets = sum.tx_packets; 132 stats->rx_bytes = sum.rx_bytes; 133 stats->rx_packets = sum.rx_packets; 134 135 return stats; 136 } 137 138 static int br_change_mtu(struct net_device *dev, int new_mtu) 139 { 140 struct net_bridge *br = netdev_priv(dev); 141 if (new_mtu < 68 || new_mtu > br_min_mtu(br)) 142 return -EINVAL; 143 144 dev->mtu = new_mtu; 145 146 #ifdef CONFIG_BRIDGE_NETFILTER 147 /* remember the MTU in the rtable for PMTU */ 148 dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu); 149 #endif 150 151 return 0; 152 } 153 154 /* Allow setting mac address to any valid ethernet address. */ 155 static int br_set_mac_address(struct net_device *dev, void *p) 156 { 157 struct net_bridge *br = netdev_priv(dev); 158 struct sockaddr *addr = p; 159 160 if (!is_valid_ether_addr(addr->sa_data)) 161 return -EINVAL; 162 163 spin_lock_bh(&br->lock); 164 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); 165 br_stp_change_bridge_id(br, addr->sa_data); 166 br->flags |= BR_SET_MAC_ADDR; 167 spin_unlock_bh(&br->lock); 168 169 return 0; 170 } 171 172 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) 173 { 174 strcpy(info->driver, "bridge"); 175 strcpy(info->version, BR_VERSION); 176 strcpy(info->fw_version, "N/A"); 177 strcpy(info->bus_info, "N/A"); 178 } 179 180 static int br_set_sg(struct net_device *dev, u32 data) 181 { 182 struct net_bridge *br = netdev_priv(dev); 183 184 if (data) 185 br->feature_mask |= NETIF_F_SG; 186 else 187 br->feature_mask &= ~NETIF_F_SG; 188 189 br_features_recompute(br); 190 return 0; 191 } 192 193 static int br_set_tso(struct net_device *dev, u32 data) 194 { 195 struct net_bridge *br = netdev_priv(dev); 196 197 if (data) 198 br->feature_mask |= NETIF_F_TSO; 199 else 200 br->feature_mask &= ~NETIF_F_TSO; 201 202 br_features_recompute(br); 203 return 0; 204 } 205 206 static int br_set_tx_csum(struct net_device *dev, u32 data) 207 { 208 struct net_bridge *br = netdev_priv(dev); 209 210 if (data) 211 br->feature_mask |= NETIF_F_NO_CSUM; 212 else 213 br->feature_mask &= ~NETIF_F_ALL_CSUM; 214 215 br_features_recompute(br); 216 return 0; 217 } 218 219 static int br_set_flags(struct net_device *netdev, u32 data) 220 { 221 return ethtool_op_set_flags(netdev, data, ETH_FLAG_TXVLAN); 222 } 223 224 #ifdef CONFIG_NET_POLL_CONTROLLER 225 static void br_poll_controller(struct net_device *br_dev) 226 { 227 } 228 229 static void br_netpoll_cleanup(struct net_device *dev) 230 { 231 struct net_bridge *br = netdev_priv(dev); 232 struct net_bridge_port *p, *n; 233 234 list_for_each_entry_safe(p, n, &br->port_list, list) { 235 br_netpoll_disable(p); 236 } 237 } 238 239 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni) 240 { 241 struct net_bridge *br = netdev_priv(dev); 242 struct net_bridge_port *p, *n; 243 int err = 0; 244 245 list_for_each_entry_safe(p, n, &br->port_list, list) { 246 if (!p->dev) 247 continue; 248 249 err = br_netpoll_enable(p); 250 if (err) 251 goto fail; 252 } 253 254 out: 255 return err; 256 257 fail: 258 br_netpoll_cleanup(dev); 259 goto out; 260 } 261 262 int br_netpoll_enable(struct net_bridge_port *p) 263 { 264 struct netpoll *np; 265 int err = 0; 266 267 np = kzalloc(sizeof(*p->np), GFP_KERNEL); 268 err = -ENOMEM; 269 if (!np) 270 goto out; 271 272 np->dev = p->dev; 273 274 err = __netpoll_setup(np); 275 if (err) { 276 kfree(np); 277 goto out; 278 } 279 280 p->np = np; 281 282 out: 283 return err; 284 } 285 286 void br_netpoll_disable(struct net_bridge_port *p) 287 { 288 struct netpoll *np = p->np; 289 290 if (!np) 291 return; 292 293 p->np = NULL; 294 295 /* Wait for transmitting packets to finish before freeing. */ 296 synchronize_rcu_bh(); 297 298 __netpoll_cleanup(np); 299 kfree(np); 300 } 301 302 #endif 303 304 static int br_add_slave(struct net_device *dev, struct net_device *slave_dev) 305 306 { 307 struct net_bridge *br = netdev_priv(dev); 308 309 return br_add_if(br, slave_dev); 310 } 311 312 static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) 313 { 314 struct net_bridge *br = netdev_priv(dev); 315 316 return br_del_if(br, slave_dev); 317 } 318 319 static const struct ethtool_ops br_ethtool_ops = { 320 .get_drvinfo = br_getinfo, 321 .get_link = ethtool_op_get_link, 322 .get_tx_csum = ethtool_op_get_tx_csum, 323 .set_tx_csum = br_set_tx_csum, 324 .get_sg = ethtool_op_get_sg, 325 .set_sg = br_set_sg, 326 .get_tso = ethtool_op_get_tso, 327 .set_tso = br_set_tso, 328 .get_ufo = ethtool_op_get_ufo, 329 .set_ufo = ethtool_op_set_ufo, 330 .get_flags = ethtool_op_get_flags, 331 .set_flags = br_set_flags, 332 }; 333 334 static const struct net_device_ops br_netdev_ops = { 335 .ndo_open = br_dev_open, 336 .ndo_stop = br_dev_stop, 337 .ndo_start_xmit = br_dev_xmit, 338 .ndo_get_stats64 = br_get_stats64, 339 .ndo_set_mac_address = br_set_mac_address, 340 .ndo_set_multicast_list = br_dev_set_multicast_list, 341 .ndo_change_mtu = br_change_mtu, 342 .ndo_do_ioctl = br_dev_ioctl, 343 #ifdef CONFIG_NET_POLL_CONTROLLER 344 .ndo_netpoll_setup = br_netpoll_setup, 345 .ndo_netpoll_cleanup = br_netpoll_cleanup, 346 .ndo_poll_controller = br_poll_controller, 347 #endif 348 .ndo_add_slave = br_add_slave, 349 .ndo_del_slave = br_del_slave, 350 }; 351 352 static void br_dev_free(struct net_device *dev) 353 { 354 struct net_bridge *br = netdev_priv(dev); 355 356 free_percpu(br->stats); 357 free_netdev(dev); 358 } 359 360 void br_dev_setup(struct net_device *dev) 361 { 362 random_ether_addr(dev->dev_addr); 363 ether_setup(dev); 364 365 dev->netdev_ops = &br_netdev_ops; 366 dev->destructor = br_dev_free; 367 SET_ETHTOOL_OPS(dev, &br_ethtool_ops); 368 dev->tx_queue_len = 0; 369 dev->priv_flags = IFF_EBRIDGE; 370 371 dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | 372 NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX | 373 NETIF_F_NETNS_LOCAL | NETIF_F_GSO | NETIF_F_HW_VLAN_TX; 374 } 375