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 br_features_recompute(br); 82 netif_start_queue(dev); 83 br_stp_enable_bridge(br); 84 br_multicast_open(br); 85 86 return 0; 87 } 88 89 static void br_dev_set_multicast_list(struct net_device *dev) 90 { 91 } 92 93 static int br_dev_stop(struct net_device *dev) 94 { 95 struct net_bridge *br = netdev_priv(dev); 96 97 br_stp_disable_bridge(br); 98 br_multicast_stop(br); 99 100 netif_stop_queue(dev); 101 102 return 0; 103 } 104 105 static struct rtnl_link_stats64 *br_get_stats64(struct net_device *dev, 106 struct rtnl_link_stats64 *stats) 107 { 108 struct net_bridge *br = netdev_priv(dev); 109 struct br_cpu_netstats tmp, sum = { 0 }; 110 unsigned int cpu; 111 112 for_each_possible_cpu(cpu) { 113 unsigned int start; 114 const struct br_cpu_netstats *bstats 115 = per_cpu_ptr(br->stats, cpu); 116 do { 117 start = u64_stats_fetch_begin(&bstats->syncp); 118 memcpy(&tmp, bstats, sizeof(tmp)); 119 } while (u64_stats_fetch_retry(&bstats->syncp, start)); 120 sum.tx_bytes += tmp.tx_bytes; 121 sum.tx_packets += tmp.tx_packets; 122 sum.rx_bytes += tmp.rx_bytes; 123 sum.rx_packets += tmp.rx_packets; 124 } 125 126 stats->tx_bytes = sum.tx_bytes; 127 stats->tx_packets = sum.tx_packets; 128 stats->rx_bytes = sum.rx_bytes; 129 stats->rx_packets = sum.rx_packets; 130 131 return stats; 132 } 133 134 static int br_change_mtu(struct net_device *dev, int new_mtu) 135 { 136 struct net_bridge *br = netdev_priv(dev); 137 if (new_mtu < 68 || new_mtu > br_min_mtu(br)) 138 return -EINVAL; 139 140 dev->mtu = new_mtu; 141 142 #ifdef CONFIG_BRIDGE_NETFILTER 143 /* remember the MTU in the rtable for PMTU */ 144 br->fake_rtable.dst.metrics[RTAX_MTU - 1] = new_mtu; 145 #endif 146 147 return 0; 148 } 149 150 /* Allow setting mac address to any valid ethernet address. */ 151 static int br_set_mac_address(struct net_device *dev, void *p) 152 { 153 struct net_bridge *br = netdev_priv(dev); 154 struct sockaddr *addr = p; 155 156 if (!is_valid_ether_addr(addr->sa_data)) 157 return -EINVAL; 158 159 spin_lock_bh(&br->lock); 160 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); 161 br_stp_change_bridge_id(br, addr->sa_data); 162 br->flags |= BR_SET_MAC_ADDR; 163 spin_unlock_bh(&br->lock); 164 165 return 0; 166 } 167 168 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) 169 { 170 strcpy(info->driver, "bridge"); 171 strcpy(info->version, BR_VERSION); 172 strcpy(info->fw_version, "N/A"); 173 strcpy(info->bus_info, "N/A"); 174 } 175 176 static int br_set_sg(struct net_device *dev, u32 data) 177 { 178 struct net_bridge *br = netdev_priv(dev); 179 180 if (data) 181 br->feature_mask |= NETIF_F_SG; 182 else 183 br->feature_mask &= ~NETIF_F_SG; 184 185 br_features_recompute(br); 186 return 0; 187 } 188 189 static int br_set_tso(struct net_device *dev, u32 data) 190 { 191 struct net_bridge *br = netdev_priv(dev); 192 193 if (data) 194 br->feature_mask |= NETIF_F_TSO; 195 else 196 br->feature_mask &= ~NETIF_F_TSO; 197 198 br_features_recompute(br); 199 return 0; 200 } 201 202 static int br_set_tx_csum(struct net_device *dev, u32 data) 203 { 204 struct net_bridge *br = netdev_priv(dev); 205 206 if (data) 207 br->feature_mask |= NETIF_F_NO_CSUM; 208 else 209 br->feature_mask &= ~NETIF_F_ALL_CSUM; 210 211 br_features_recompute(br); 212 return 0; 213 } 214 215 #ifdef CONFIG_NET_POLL_CONTROLLER 216 static void br_poll_controller(struct net_device *br_dev) 217 { 218 } 219 220 static void br_netpoll_cleanup(struct net_device *dev) 221 { 222 struct net_bridge *br = netdev_priv(dev); 223 struct net_bridge_port *p, *n; 224 225 list_for_each_entry_safe(p, n, &br->port_list, list) { 226 br_netpoll_disable(p); 227 } 228 } 229 230 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni) 231 { 232 struct net_bridge *br = netdev_priv(dev); 233 struct net_bridge_port *p, *n; 234 int err = 0; 235 236 list_for_each_entry_safe(p, n, &br->port_list, list) { 237 if (!p->dev) 238 continue; 239 240 err = br_netpoll_enable(p); 241 if (err) 242 goto fail; 243 } 244 245 out: 246 return err; 247 248 fail: 249 br_netpoll_cleanup(dev); 250 goto out; 251 } 252 253 int br_netpoll_enable(struct net_bridge_port *p) 254 { 255 struct netpoll *np; 256 int err = 0; 257 258 np = kzalloc(sizeof(*p->np), GFP_KERNEL); 259 err = -ENOMEM; 260 if (!np) 261 goto out; 262 263 np->dev = p->dev; 264 265 err = __netpoll_setup(np); 266 if (err) { 267 kfree(np); 268 goto out; 269 } 270 271 p->np = np; 272 273 out: 274 return err; 275 } 276 277 void br_netpoll_disable(struct net_bridge_port *p) 278 { 279 struct netpoll *np = p->np; 280 281 if (!np) 282 return; 283 284 p->np = NULL; 285 286 /* Wait for transmitting packets to finish before freeing. */ 287 synchronize_rcu_bh(); 288 289 __netpoll_cleanup(np); 290 kfree(np); 291 } 292 293 #endif 294 295 static const struct ethtool_ops br_ethtool_ops = { 296 .get_drvinfo = br_getinfo, 297 .get_link = ethtool_op_get_link, 298 .get_tx_csum = ethtool_op_get_tx_csum, 299 .set_tx_csum = br_set_tx_csum, 300 .get_sg = ethtool_op_get_sg, 301 .set_sg = br_set_sg, 302 .get_tso = ethtool_op_get_tso, 303 .set_tso = br_set_tso, 304 .get_ufo = ethtool_op_get_ufo, 305 .set_ufo = ethtool_op_set_ufo, 306 .get_flags = ethtool_op_get_flags, 307 }; 308 309 static const struct net_device_ops br_netdev_ops = { 310 .ndo_open = br_dev_open, 311 .ndo_stop = br_dev_stop, 312 .ndo_start_xmit = br_dev_xmit, 313 .ndo_get_stats64 = br_get_stats64, 314 .ndo_set_mac_address = br_set_mac_address, 315 .ndo_set_multicast_list = br_dev_set_multicast_list, 316 .ndo_change_mtu = br_change_mtu, 317 .ndo_do_ioctl = br_dev_ioctl, 318 #ifdef CONFIG_NET_POLL_CONTROLLER 319 .ndo_netpoll_setup = br_netpoll_setup, 320 .ndo_netpoll_cleanup = br_netpoll_cleanup, 321 .ndo_poll_controller = br_poll_controller, 322 #endif 323 }; 324 325 static void br_dev_free(struct net_device *dev) 326 { 327 struct net_bridge *br = netdev_priv(dev); 328 329 free_percpu(br->stats); 330 free_netdev(dev); 331 } 332 333 void br_dev_setup(struct net_device *dev) 334 { 335 random_ether_addr(dev->dev_addr); 336 ether_setup(dev); 337 338 dev->netdev_ops = &br_netdev_ops; 339 dev->destructor = br_dev_free; 340 SET_ETHTOOL_OPS(dev, &br_ethtool_ops); 341 dev->tx_queue_len = 0; 342 dev->priv_flags = IFF_EBRIDGE; 343 344 dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | 345 NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX | 346 NETIF_F_NETNS_LOCAL | NETIF_F_GSO; 347 } 348