// SPDX-License-Identifier: GPL-2.0-or-later /* * Device handling code * Linux ethernet bridge * * Authors: * Lennert Buytenhek */ #include #include #include #include #include #include #include #include #include "br_private.h" #define COMMON_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | \ NETIF_F_GSO_MASK | NETIF_F_HW_CSUM) const struct nf_br_ops __rcu *nf_br_ops __read_mostly; EXPORT_SYMBOL_GPL(nf_br_ops); /* net device transmit always called with BH disabled */ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev) { struct net_bridge_mcast_port *pmctx_null = NULL; struct net_bridge *br = netdev_priv(dev); struct net_bridge_mcast *brmctx = &br->multicast_ctx; struct net_bridge_fdb_entry *dst; struct net_bridge_mdb_entry *mdst; const struct nf_br_ops *nf_ops; u8 state = BR_STATE_FORWARDING; struct net_bridge_vlan *vlan; const unsigned char *dest; u16 vid = 0; memset(skb->cb, 0, sizeof(struct br_input_skb_cb)); rcu_read_lock(); nf_ops = rcu_dereference(nf_br_ops); if (nf_ops && nf_ops->br_dev_xmit_hook(skb)) { rcu_read_unlock(); return NETDEV_TX_OK; } dev_sw_netstats_tx_add(dev, 1, skb->len); br_switchdev_frame_unmark(skb); BR_INPUT_SKB_CB(skb)->brdev = dev; BR_INPUT_SKB_CB(skb)->frag_max_size = 0; skb_reset_mac_header(skb); skb_pull(skb, ETH_HLEN); if (!br_allowed_ingress(br, br_vlan_group_rcu(br), skb, &vid, &state, &vlan)) goto out; if (IS_ENABLED(CONFIG_INET) && (eth_hdr(skb)->h_proto == htons(ETH_P_ARP) || eth_hdr(skb)->h_proto == htons(ETH_P_RARP)) && br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) { br_do_proxy_suppress_arp(skb, br, vid, NULL); } else if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6) && br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED) && pskb_may_pull(skb, sizeof(struct ipv6hdr) + sizeof(struct nd_msg)) && ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) { struct nd_msg *msg, _msg; msg = br_is_nd_neigh_msg(skb, &_msg); if (msg) br_do_suppress_nd(skb, br, vid, NULL, msg); } dest = eth_hdr(skb)->h_dest; if (is_broadcast_ether_addr(dest)) { br_flood(br, skb, BR_PKT_BROADCAST, false, true); } else if (is_multicast_ether_addr(dest)) { if (unlikely(netpoll_tx_running(dev))) { br_flood(br, skb, BR_PKT_MULTICAST, false, true); goto out; } if (br_multicast_rcv(&brmctx, &pmctx_null, vlan, skb, vid)) { kfree_skb(skb); goto out; } mdst = br_mdb_get(brmctx, skb, vid); if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) && br_multicast_querier_exists(brmctx, eth_hdr(skb), mdst)) br_multicast_flood(mdst, skb, brmctx, false, true); else br_flood(br, skb, BR_PKT_MULTICAST, false, true); } else if ((dst = br_fdb_find_rcu(br, dest, vid)) != NULL) { br_forward(dst->dst, skb, false, true); } else { br_flood(br, skb, BR_PKT_UNICAST, false, true); } out: rcu_read_unlock(); return NETDEV_TX_OK; } static struct lock_class_key bridge_netdev_addr_lock_key; static void br_set_lockdep_class(struct net_device *dev) { lockdep_set_class(&dev->addr_list_lock, &bridge_netdev_addr_lock_key); } static int br_dev_init(struct net_device *dev) { struct net_bridge *br = netdev_priv(dev); int err; dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); if (!dev->tstats) return -ENOMEM; err = br_fdb_hash_init(br); if (err) { free_percpu(dev->tstats); return err; } err = br_mdb_hash_init(br); if (err) { free_percpu(dev->tstats); br_fdb_hash_fini(br); return err; } err = br_vlan_init(br); if (err) { free_percpu(dev->tstats); br_mdb_hash_fini(br); br_fdb_hash_fini(br); return err; } err = br_multicast_init_stats(br); if (err) { free_percpu(dev->tstats); br_vlan_flush(br); br_mdb_hash_fini(br); br_fdb_hash_fini(br); } br_set_lockdep_class(dev); return err; } static void br_dev_uninit(struct net_device *dev) { struct net_bridge *br = netdev_priv(dev); br_multicast_dev_del(br); br_multicast_uninit_stats(br); br_vlan_flush(br); br_mdb_hash_fini(br); br_fdb_hash_fini(br); free_percpu(dev->tstats); } static int br_dev_open(struct net_device *dev) { struct net_bridge *br = netdev_priv(dev); netdev_update_features(dev); netif_start_queue(dev); br_stp_enable_bridge(br); br_multicast_open(br); if (br_opt_get(br, BROPT_MULTICAST_ENABLED)) br_multicast_join_snoopers(br); return 0; } static void br_dev_set_multicast_list(struct net_device *dev) { } static void br_dev_change_rx_flags(struct net_device *dev, int change) { if (change & IFF_PROMISC) br_manage_promisc(netdev_priv(dev)); } static int br_dev_stop(struct net_device *dev) { struct net_bridge *br = netdev_priv(dev); br_stp_disable_bridge(br); br_multicast_stop(br); if (br_opt_get(br, BROPT_MULTICAST_ENABLED)) br_multicast_leave_snoopers(br); netif_stop_queue(dev); return 0; } static int br_change_mtu(struct net_device *dev, int new_mtu) { struct net_bridge *br = netdev_priv(dev); dev->mtu = new_mtu; /* this flag will be cleared if the MTU was automatically adjusted */ br_opt_toggle(br, BROPT_MTU_SET_BY_USER, true); #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) /* remember the MTU in the rtable for PMTU */ dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu); #endif return 0; } /* Allow setting mac address to any valid ethernet address. */ static int br_set_mac_address(struct net_device *dev, void *p) { struct net_bridge *br = netdev_priv(dev); struct sockaddr *addr = p; if (!is_valid_ether_addr(addr->sa_data)) return -EADDRNOTAVAIL; /* dev_set_mac_addr() can be called by a master device on bridge's * NETDEV_UNREGISTER, but since it's being destroyed do nothing */ if (dev->reg_state != NETREG_REGISTERED) return -EBUSY; spin_lock_bh(&br->lock); if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) { /* Mac address will be changed in br_stp_change_bridge_id(). */ br_stp_change_bridge_id(br, addr->sa_data); } spin_unlock_bh(&br->lock); return 0; } static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info) { strlcpy(info->driver, "bridge", sizeof(info->driver)); strlcpy(info->version, BR_VERSION, sizeof(info->version)); strlcpy(info->fw_version, "N/A", sizeof(info->fw_version)); strlcpy(info->bus_info, "N/A", sizeof(info->bus_info)); } static int br_get_link_ksettings(struct net_device *dev, struct ethtool_link_ksettings *cmd) { struct net_bridge *br = netdev_priv(dev); struct net_bridge_port *p; cmd->base.duplex = DUPLEX_UNKNOWN; cmd->base.port = PORT_OTHER; cmd->base.speed = SPEED_UNKNOWN; list_for_each_entry(p, &br->port_list, list) { struct ethtool_link_ksettings ecmd; struct net_device *pdev = p->dev; if (!netif_running(pdev) || !netif_oper_up(pdev)) continue; if (__ethtool_get_link_ksettings(pdev, &ecmd)) continue; if (ecmd.base.speed == (__u32)SPEED_UNKNOWN) continue; if (cmd->base.speed == (__u32)SPEED_UNKNOWN || cmd->base.speed < ecmd.base.speed) cmd->base.speed = ecmd.base.speed; } return 0; } static netdev_features_t br_fix_features(struct net_device *dev, netdev_features_t features) { struct net_bridge *br = netdev_priv(dev); return br_features_recompute(br, features); } #ifdef CONFIG_NET_POLL_CONTROLLER static void br_poll_controller(struct net_device *br_dev) { } static void br_netpoll_cleanup(struct net_device *dev) { struct net_bridge *br = netdev_priv(dev); struct net_bridge_port *p; list_for_each_entry(p, &br->port_list, list) br_netpoll_disable(p); } static int __br_netpoll_enable(struct net_bridge_port *p) { struct netpoll *np; int err; np = kzalloc(sizeof(*p->np), GFP_KERNEL); if (!np) return -ENOMEM; err = __netpoll_setup(np, p->dev); if (err) { kfree(np); return err; } p->np = np; return err; } int br_netpoll_enable(struct net_bridge_port *p) { if (!p->br->dev->npinfo) return 0; return __br_netpoll_enable(p); } static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni) { struct net_bridge *br = netdev_priv(dev); struct net_bridge_port *p; int err = 0; list_for_each_entry(p, &br->port_list, list) { if (!p->dev) continue; err = __br_netpoll_enable(p); if (err) goto fail; } out: return err; fail: br_netpoll_cleanup(dev); goto out; } void br_netpoll_disable(struct net_bridge_port *p) { struct netpoll *np = p->np; if (!np) return; p->np = NULL; __netpoll_free(np); } #endif static int br_add_slave(struct net_device *dev, struct net_device *slave_dev, struct netlink_ext_ack *extack) { struct net_bridge *br = netdev_priv(dev); return br_add_if(br, slave_dev, extack); } static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) { struct net_bridge *br = netdev_priv(dev); return br_del_if(br, slave_dev); } static int br_fill_forward_path(struct net_device_path_ctx *ctx, struct net_device_path *path) { struct net_bridge_fdb_entry *f; struct net_bridge_port *dst; struct net_bridge *br; if (netif_is_bridge_port(ctx->dev)) return -1; br = netdev_priv(ctx->dev); br_vlan_fill_forward_path_pvid(br, ctx, path); f = br_fdb_find_rcu(br, ctx->daddr, path->bridge.vlan_id); if (!f || !f->dst) return -1; dst = READ_ONCE(f->dst); if (!dst) return -1; if (br_vlan_fill_forward_path_mode(br, dst, path)) return -1; path->type = DEV_PATH_BRIDGE; path->dev = dst->br->dev; ctx->dev = dst->dev; switch (path->bridge.vlan_mode) { case DEV_PATH_BR_VLAN_TAG: if (ctx->num_vlans >= ARRAY_SIZE(ctx->vlan)) return -ENOSPC; ctx->vlan[ctx->num_vlans].id = path->bridge.vlan_id; ctx->vlan[ctx->num_vlans].proto = path->bridge.vlan_proto; ctx->num_vlans++; break; case DEV_PATH_BR_VLAN_UNTAG_HW: case DEV_PATH_BR_VLAN_UNTAG: ctx->num_vlans--; break; case DEV_PATH_BR_VLAN_KEEP: break; } return 0; } static const struct ethtool_ops br_ethtool_ops = { .get_drvinfo = br_getinfo, .get_link = ethtool_op_get_link, .get_link_ksettings = br_get_link_ksettings, }; static const struct net_device_ops br_netdev_ops = { .ndo_open = br_dev_open, .ndo_stop = br_dev_stop, .ndo_init = br_dev_init, .ndo_uninit = br_dev_uninit, .ndo_start_xmit = br_dev_xmit, .ndo_get_stats64 = dev_get_tstats64, .ndo_set_mac_address = br_set_mac_address, .ndo_set_rx_mode = br_dev_set_multicast_list, .ndo_change_rx_flags = br_dev_change_rx_flags, .ndo_change_mtu = br_change_mtu, .ndo_do_ioctl = br_dev_ioctl, #ifdef CONFIG_NET_POLL_CONTROLLER .ndo_netpoll_setup = br_netpoll_setup, .ndo_netpoll_cleanup = br_netpoll_cleanup, .ndo_poll_controller = br_poll_controller, #endif .ndo_add_slave = br_add_slave, .ndo_del_slave = br_del_slave, .ndo_fix_features = br_fix_features, .ndo_fdb_add = br_fdb_add, .ndo_fdb_del = br_fdb_delete, .ndo_fdb_dump = br_fdb_dump, .ndo_fdb_get = br_fdb_get, .ndo_bridge_getlink = br_getlink, .ndo_bridge_setlink = br_setlink, .ndo_bridge_dellink = br_dellink, .ndo_features_check = passthru_features_check, .ndo_fill_forward_path = br_fill_forward_path, }; static struct device_type br_type = { .name = "bridge", }; void br_dev_setup(struct net_device *dev) { struct net_bridge *br = netdev_priv(dev); eth_hw_addr_random(dev); ether_setup(dev); dev->netdev_ops = &br_netdev_ops; dev->needs_free_netdev = true; dev->ethtool_ops = &br_ethtool_ops; SET_NETDEV_DEVTYPE(dev, &br_type); dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE; dev->features = COMMON_FEATURES | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL | NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX; dev->hw_features = COMMON_FEATURES | NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX; dev->vlan_features = COMMON_FEATURES; br->dev = dev; spin_lock_init(&br->lock); INIT_LIST_HEAD(&br->port_list); INIT_HLIST_HEAD(&br->fdb_list); INIT_HLIST_HEAD(&br->frame_type_list); #if IS_ENABLED(CONFIG_BRIDGE_MRP) INIT_HLIST_HEAD(&br->mrp_list); #endif #if IS_ENABLED(CONFIG_BRIDGE_CFM) INIT_HLIST_HEAD(&br->mep_list); #endif spin_lock_init(&br->hash_lock); br->bridge_id.prio[0] = 0x80; br->bridge_id.prio[1] = 0x00; ether_addr_copy(br->group_addr, eth_stp_addr); br->stp_enabled = BR_NO_STP; br->group_fwd_mask = BR_GROUPFWD_DEFAULT; br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT; br->designated_root = br->bridge_id; br->bridge_max_age = br->max_age = 20 * HZ; br->bridge_hello_time = br->hello_time = 2 * HZ; br->bridge_forward_delay = br->forward_delay = 15 * HZ; br->bridge_ageing_time = br->ageing_time = BR_DEFAULT_AGEING_TIME; dev->max_mtu = ETH_MAX_MTU; br_netfilter_rtable_init(br); br_stp_timer_init(br); br_multicast_init(br); INIT_DELAYED_WORK(&br->gc_work, br_fdb_cleanup); }