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 no BH (preempt_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 brstats->tx_packets++; 42 brstats->tx_bytes += skb->len; 43 44 BR_INPUT_SKB_CB(skb)->brdev = dev; 45 46 skb_reset_mac_header(skb); 47 skb_pull(skb, ETH_HLEN); 48 49 if (is_multicast_ether_addr(dest)) { 50 if (br_multicast_rcv(br, NULL, skb)) 51 goto out; 52 53 mdst = br_mdb_get(br, skb); 54 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) 55 br_multicast_deliver(mdst, skb); 56 else 57 br_flood_deliver(br, skb); 58 } else if ((dst = __br_fdb_get(br, dest)) != NULL) 59 br_deliver(dst->dst, skb); 60 else 61 br_flood_deliver(br, skb); 62 63 out: 64 return NETDEV_TX_OK; 65 } 66 67 static int br_dev_open(struct net_device *dev) 68 { 69 struct net_bridge *br = netdev_priv(dev); 70 71 br_features_recompute(br); 72 netif_start_queue(dev); 73 br_stp_enable_bridge(br); 74 br_multicast_open(br); 75 76 return 0; 77 } 78 79 static void br_dev_set_multicast_list(struct net_device *dev) 80 { 81 } 82 83 static int br_dev_stop(struct net_device *dev) 84 { 85 struct net_bridge *br = netdev_priv(dev); 86 87 br_stp_disable_bridge(br); 88 br_multicast_stop(br); 89 90 netif_stop_queue(dev); 91 92 return 0; 93 } 94 95 static struct net_device_stats *br_get_stats(struct net_device *dev) 96 { 97 struct net_bridge *br = netdev_priv(dev); 98 struct net_device_stats *stats = &dev->stats; 99 struct br_cpu_netstats sum = { 0 }; 100 unsigned int cpu; 101 102 for_each_possible_cpu(cpu) { 103 const struct br_cpu_netstats *bstats 104 = per_cpu_ptr(br->stats, cpu); 105 106 sum.tx_bytes += bstats->tx_bytes; 107 sum.tx_packets += bstats->tx_packets; 108 sum.rx_bytes += bstats->rx_bytes; 109 sum.rx_packets += bstats->rx_packets; 110 } 111 112 stats->tx_bytes = sum.tx_bytes; 113 stats->tx_packets = sum.tx_packets; 114 stats->rx_bytes = sum.rx_bytes; 115 stats->rx_packets = sum.rx_packets; 116 117 return stats; 118 } 119 120 static int br_change_mtu(struct net_device *dev, int new_mtu) 121 { 122 struct net_bridge *br = netdev_priv(dev); 123 if (new_mtu < 68 || new_mtu > br_min_mtu(br)) 124 return -EINVAL; 125 126 dev->mtu = new_mtu; 127 128 #ifdef CONFIG_BRIDGE_NETFILTER 129 /* remember the MTU in the rtable for PMTU */ 130 br->fake_rtable.u.dst.metrics[RTAX_MTU - 1] = new_mtu; 131 #endif 132 133 return 0; 134 } 135 136 /* Allow setting mac address to any valid ethernet address. */ 137 static int br_set_mac_address(struct net_device *dev, void *p) 138 { 139 struct net_bridge *br = netdev_priv(dev); 140 struct sockaddr *addr = p; 141 142 if (!is_valid_ether_addr(addr->sa_data)) 143 return -EINVAL; 144 145 spin_lock_bh(&br->lock); 146 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); 147 br_stp_change_bridge_id(br, addr->sa_data); 148 br->flags |= BR_SET_MAC_ADDR; 149 spin_unlock_bh(&br->lock); 150 151 return 0; 152 } 153 154 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) 155 { 156 strcpy(info->driver, "bridge"); 157 strcpy(info->version, BR_VERSION); 158 strcpy(info->fw_version, "N/A"); 159 strcpy(info->bus_info, "N/A"); 160 } 161 162 static int br_set_sg(struct net_device *dev, u32 data) 163 { 164 struct net_bridge *br = netdev_priv(dev); 165 166 if (data) 167 br->feature_mask |= NETIF_F_SG; 168 else 169 br->feature_mask &= ~NETIF_F_SG; 170 171 br_features_recompute(br); 172 return 0; 173 } 174 175 static int br_set_tso(struct net_device *dev, u32 data) 176 { 177 struct net_bridge *br = netdev_priv(dev); 178 179 if (data) 180 br->feature_mask |= NETIF_F_TSO; 181 else 182 br->feature_mask &= ~NETIF_F_TSO; 183 184 br_features_recompute(br); 185 return 0; 186 } 187 188 static int br_set_tx_csum(struct net_device *dev, u32 data) 189 { 190 struct net_bridge *br = netdev_priv(dev); 191 192 if (data) 193 br->feature_mask |= NETIF_F_NO_CSUM; 194 else 195 br->feature_mask &= ~NETIF_F_ALL_CSUM; 196 197 br_features_recompute(br); 198 return 0; 199 } 200 201 #ifdef CONFIG_NET_POLL_CONTROLLER 202 static bool br_devices_support_netpoll(struct net_bridge *br) 203 { 204 struct net_bridge_port *p; 205 bool ret = true; 206 int count = 0; 207 unsigned long flags; 208 209 spin_lock_irqsave(&br->lock, flags); 210 list_for_each_entry(p, &br->port_list, list) { 211 count++; 212 if ((p->dev->priv_flags & IFF_DISABLE_NETPOLL) || 213 !p->dev->netdev_ops->ndo_poll_controller) 214 ret = false; 215 } 216 spin_unlock_irqrestore(&br->lock, flags); 217 return count != 0 && ret; 218 } 219 220 static void br_poll_controller(struct net_device *br_dev) 221 { 222 struct netpoll *np = br_dev->npinfo->netpoll; 223 224 if (np->real_dev != br_dev) 225 netpoll_poll_dev(np->real_dev); 226 } 227 228 void br_netpoll_cleanup(struct net_device *dev) 229 { 230 struct net_bridge *br = netdev_priv(dev); 231 struct net_bridge_port *p, *n; 232 const struct net_device_ops *ops; 233 234 br->dev->npinfo = NULL; 235 list_for_each_entry_safe(p, n, &br->port_list, list) { 236 if (p->dev) { 237 ops = p->dev->netdev_ops; 238 if (ops->ndo_netpoll_cleanup) 239 ops->ndo_netpoll_cleanup(p->dev); 240 else 241 p->dev->npinfo = NULL; 242 } 243 } 244 } 245 246 void br_netpoll_disable(struct net_bridge *br, 247 struct net_device *dev) 248 { 249 if (br_devices_support_netpoll(br)) 250 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL; 251 if (dev->netdev_ops->ndo_netpoll_cleanup) 252 dev->netdev_ops->ndo_netpoll_cleanup(dev); 253 else 254 dev->npinfo = NULL; 255 } 256 257 void br_netpoll_enable(struct net_bridge *br, 258 struct net_device *dev) 259 { 260 if (br_devices_support_netpoll(br)) { 261 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL; 262 if (br->dev->npinfo) 263 dev->npinfo = br->dev->npinfo; 264 } else if (!(br->dev->priv_flags & IFF_DISABLE_NETPOLL)) { 265 br->dev->priv_flags |= IFF_DISABLE_NETPOLL; 266 br_info(br,"new device %s does not support netpoll (disabling)", 267 dev->name); 268 } 269 } 270 271 #endif 272 273 static const struct ethtool_ops br_ethtool_ops = { 274 .get_drvinfo = br_getinfo, 275 .get_link = ethtool_op_get_link, 276 .get_tx_csum = ethtool_op_get_tx_csum, 277 .set_tx_csum = br_set_tx_csum, 278 .get_sg = ethtool_op_get_sg, 279 .set_sg = br_set_sg, 280 .get_tso = ethtool_op_get_tso, 281 .set_tso = br_set_tso, 282 .get_ufo = ethtool_op_get_ufo, 283 .set_ufo = ethtool_op_set_ufo, 284 .get_flags = ethtool_op_get_flags, 285 }; 286 287 static const struct net_device_ops br_netdev_ops = { 288 .ndo_open = br_dev_open, 289 .ndo_stop = br_dev_stop, 290 .ndo_start_xmit = br_dev_xmit, 291 .ndo_get_stats = br_get_stats, 292 .ndo_set_mac_address = br_set_mac_address, 293 .ndo_set_multicast_list = br_dev_set_multicast_list, 294 .ndo_change_mtu = br_change_mtu, 295 .ndo_do_ioctl = br_dev_ioctl, 296 #ifdef CONFIG_NET_POLL_CONTROLLER 297 .ndo_netpoll_cleanup = br_netpoll_cleanup, 298 .ndo_poll_controller = br_poll_controller, 299 #endif 300 }; 301 302 static void br_dev_free(struct net_device *dev) 303 { 304 struct net_bridge *br = netdev_priv(dev); 305 306 free_percpu(br->stats); 307 free_netdev(dev); 308 } 309 310 void br_dev_setup(struct net_device *dev) 311 { 312 random_ether_addr(dev->dev_addr); 313 ether_setup(dev); 314 315 dev->netdev_ops = &br_netdev_ops; 316 dev->destructor = br_dev_free; 317 SET_ETHTOOL_OPS(dev, &br_ethtool_ops); 318 dev->tx_queue_len = 0; 319 dev->priv_flags = IFF_EBRIDGE; 320 321 dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | 322 NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX | 323 NETIF_F_NETNS_LOCAL | NETIF_F_GSO; 324 } 325