11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * Forwarding decision 31da177e4SLinus Torvalds * Linux ethernet bridge 41da177e4SLinus Torvalds * 51da177e4SLinus Torvalds * Authors: 61da177e4SLinus Torvalds * Lennert Buytenhek <buytenh@gnu.org> 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or 91da177e4SLinus Torvalds * modify it under the terms of the GNU General Public License 101da177e4SLinus Torvalds * as published by the Free Software Foundation; either version 111da177e4SLinus Torvalds * 2 of the License, or (at your option) any later version. 121da177e4SLinus Torvalds */ 131da177e4SLinus Torvalds 14025d89c2SHerbert Xu #include <linux/err.h> 155a0e3ad6STejun Heo #include <linux/slab.h> 161da177e4SLinus Torvalds #include <linux/kernel.h> 171da177e4SLinus Torvalds #include <linux/netdevice.h> 18c06ee961SWANG Cong #include <linux/netpoll.h> 191da177e4SLinus Torvalds #include <linux/skbuff.h> 2085ca719eSStephen Hemminger #include <linux/if_vlan.h> 211da177e4SLinus Torvalds #include <linux/netfilter_bridge.h> 221da177e4SLinus Torvalds #include "br_private.h" 231da177e4SLinus Torvalds 241a81a2e0Stanxiaojun /* Don't forward packets to originating port or forwarding disabled */ 251da177e4SLinus Torvalds static inline int should_deliver(const struct net_bridge_port *p, 261da177e4SLinus Torvalds const struct sk_buff *skb) 271da177e4SLinus Torvalds { 282594e906SNikolay Aleksandrov struct net_bridge_vlan_group *vg; 292594e906SNikolay Aleksandrov 30907b1e6eSNikolay Aleksandrov vg = nbp_vlan_group_rcu(p); 31a97bfc1dStanxiaojun return ((p->flags & BR_HAIRPIN_MODE) || skb->dev != p->dev) && 326bc506b4SIdo Schimmel br_allowed_egress(vg, skb) && p->state == BR_STATE_FORWARDING && 336bc506b4SIdo Schimmel nbp_switchdev_allowed_egress(p, skb); 341da177e4SLinus Torvalds } 351da177e4SLinus Torvalds 360c4b51f0SEric W. Biederman int br_dev_queue_push_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 371da177e4SLinus Torvalds { 38df356d5eSToshiaki Makita if (!is_skb_forwardable(skb->dev, skb)) 39df356d5eSToshiaki Makita goto drop; 40df356d5eSToshiaki Makita 411da177e4SLinus Torvalds skb_push(skb, ETH_HLEN); 42a881e963SPeter Huang (Peng) br_drop_fake_rtable(skb); 43df356d5eSToshiaki Makita 44df356d5eSToshiaki Makita if (skb->ip_summed == CHECKSUM_PARTIAL && 45df356d5eSToshiaki Makita (skb->protocol == htons(ETH_P_8021Q) || 46df356d5eSToshiaki Makita skb->protocol == htons(ETH_P_8021AD))) { 47df356d5eSToshiaki Makita int depth; 48df356d5eSToshiaki Makita 49df356d5eSToshiaki Makita if (!__vlan_get_protocol(skb, skb->protocol, &depth)) 50df356d5eSToshiaki Makita goto drop; 51df356d5eSToshiaki Makita 52df356d5eSToshiaki Makita skb_set_network_header(skb, depth); 531da177e4SLinus Torvalds } 541da177e4SLinus Torvalds 55df356d5eSToshiaki Makita dev_queue_xmit(skb); 56df356d5eSToshiaki Makita 57df356d5eSToshiaki Makita return 0; 58df356d5eSToshiaki Makita 59df356d5eSToshiaki Makita drop: 60df356d5eSToshiaki Makita kfree_skb(skb); 611da177e4SLinus Torvalds return 0; 621da177e4SLinus Torvalds } 6334666d46SPablo Neira Ayuso EXPORT_SYMBOL_GPL(br_dev_queue_push_xmit); 641da177e4SLinus Torvalds 650c4b51f0SEric W. Biederman int br_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb) 661da177e4SLinus Torvalds { 6729a26a56SEric W. Biederman return NF_HOOK(NFPROTO_BRIDGE, NF_BR_POST_ROUTING, 6829a26a56SEric W. Biederman net, sk, skb, NULL, skb->dev, 691da177e4SLinus Torvalds br_dev_queue_push_xmit); 701da177e4SLinus Torvalds 711da177e4SLinus Torvalds } 7234666d46SPablo Neira Ayuso EXPORT_SYMBOL_GPL(br_forward_finish); 731da177e4SLinus Torvalds 7437b090e6SNikolay Aleksandrov static void __br_forward(const struct net_bridge_port *to, 7537b090e6SNikolay Aleksandrov struct sk_buff *skb, bool local_orig) 761da177e4SLinus Torvalds { 772594e906SNikolay Aleksandrov struct net_bridge_vlan_group *vg; 781da177e4SLinus Torvalds struct net_device *indev; 7937b090e6SNikolay Aleksandrov struct net *net; 8037b090e6SNikolay Aleksandrov int br_hook; 814906f998SHerbert Xu 82907b1e6eSNikolay Aleksandrov vg = nbp_vlan_group_rcu(to); 832594e906SNikolay Aleksandrov skb = br_handle_vlan(to->br, vg, skb); 8478851988SVlad Yasevich if (!skb) 8578851988SVlad Yasevich return; 8678851988SVlad Yasevich 871da177e4SLinus Torvalds indev = skb->dev; 881da177e4SLinus Torvalds skb->dev = to->dev; 8937b090e6SNikolay Aleksandrov if (!local_orig) { 9037b090e6SNikolay Aleksandrov if (skb_warn_if_lro(skb)) { 9137b090e6SNikolay Aleksandrov kfree_skb(skb); 9237b090e6SNikolay Aleksandrov return; 9337b090e6SNikolay Aleksandrov } 9437b090e6SNikolay Aleksandrov br_hook = NF_BR_FORWARD; 9535fc92a9SHerbert Xu skb_forward_csum(skb); 9637b090e6SNikolay Aleksandrov net = dev_net(indev); 9737b090e6SNikolay Aleksandrov } else { 9837b090e6SNikolay Aleksandrov if (unlikely(netpoll_tx_running(to->br->dev))) { 9937b090e6SNikolay Aleksandrov if (!is_skb_forwardable(skb->dev, skb)) { 10037b090e6SNikolay Aleksandrov kfree_skb(skb); 10137b090e6SNikolay Aleksandrov } else { 10237b090e6SNikolay Aleksandrov skb_push(skb, ETH_HLEN); 10337b090e6SNikolay Aleksandrov br_netpoll_send_skb(to, skb); 10437b090e6SNikolay Aleksandrov } 10537b090e6SNikolay Aleksandrov return; 10637b090e6SNikolay Aleksandrov } 10737b090e6SNikolay Aleksandrov br_hook = NF_BR_LOCAL_OUT; 10837b090e6SNikolay Aleksandrov net = dev_net(skb->dev); 10937b090e6SNikolay Aleksandrov indev = NULL; 11037b090e6SNikolay Aleksandrov } 1111da177e4SLinus Torvalds 11237b090e6SNikolay Aleksandrov NF_HOOK(NFPROTO_BRIDGE, br_hook, 11337b090e6SNikolay Aleksandrov net, NULL, skb, indev, skb->dev, 1141da177e4SLinus Torvalds br_forward_finish); 1151da177e4SLinus Torvalds } 1161da177e4SLinus Torvalds 11787faf3ccSDavid S. Miller static int deliver_clone(const struct net_bridge_port *prev, 11837b090e6SNikolay Aleksandrov struct sk_buff *skb, bool local_orig) 119025d89c2SHerbert Xu { 120025d89c2SHerbert Xu struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev; 121025d89c2SHerbert Xu 122fed396a5SHerbert Xu skb = skb_clone(skb, GFP_ATOMIC); 123fed396a5SHerbert Xu if (!skb) { 124025d89c2SHerbert Xu dev->stats.tx_dropped++; 125025d89c2SHerbert Xu return -ENOMEM; 126025d89c2SHerbert Xu } 127025d89c2SHerbert Xu 12837b090e6SNikolay Aleksandrov __br_forward(prev, skb, local_orig); 129025d89c2SHerbert Xu return 0; 130025d89c2SHerbert Xu } 131025d89c2SHerbert Xu 13237b090e6SNikolay Aleksandrov /** 13337b090e6SNikolay Aleksandrov * br_forward - forward a packet to a specific port 13437b090e6SNikolay Aleksandrov * @to: destination port 13537b090e6SNikolay Aleksandrov * @skb: packet being forwarded 13637b090e6SNikolay Aleksandrov * @local_rcv: packet will be received locally after forwarding 13737b090e6SNikolay Aleksandrov * @local_orig: packet is locally originated 13837b090e6SNikolay Aleksandrov * 13937b090e6SNikolay Aleksandrov * Should be called with rcu_read_lock. 14037b090e6SNikolay Aleksandrov */ 14137b090e6SNikolay Aleksandrov void br_forward(const struct net_bridge_port *to, 14237b090e6SNikolay Aleksandrov struct sk_buff *skb, bool local_rcv, bool local_orig) 14337b090e6SNikolay Aleksandrov { 14437b090e6SNikolay Aleksandrov if (to && should_deliver(to, skb)) { 14537b090e6SNikolay Aleksandrov if (local_rcv) 14637b090e6SNikolay Aleksandrov deliver_clone(to, skb, local_orig); 14737b090e6SNikolay Aleksandrov else 14837b090e6SNikolay Aleksandrov __br_forward(to, skb, local_orig); 14937b090e6SNikolay Aleksandrov return; 15037b090e6SNikolay Aleksandrov } 15137b090e6SNikolay Aleksandrov 15237b090e6SNikolay Aleksandrov if (!local_rcv) 15337b090e6SNikolay Aleksandrov kfree_skb(skb); 15437b090e6SNikolay Aleksandrov } 15537b090e6SNikolay Aleksandrov EXPORT_SYMBOL_GPL(br_forward); 15637b090e6SNikolay Aleksandrov 157025d89c2SHerbert Xu static struct net_bridge_port *maybe_deliver( 158025d89c2SHerbert Xu struct net_bridge_port *prev, struct net_bridge_port *p, 15937b090e6SNikolay Aleksandrov struct sk_buff *skb, bool local_orig) 160025d89c2SHerbert Xu { 161025d89c2SHerbert Xu int err; 162025d89c2SHerbert Xu 163025d89c2SHerbert Xu if (!should_deliver(p, skb)) 164025d89c2SHerbert Xu return prev; 165025d89c2SHerbert Xu 166025d89c2SHerbert Xu if (!prev) 167025d89c2SHerbert Xu goto out; 168025d89c2SHerbert Xu 16937b090e6SNikolay Aleksandrov err = deliver_clone(prev, skb, local_orig); 170025d89c2SHerbert Xu if (err) 171025d89c2SHerbert Xu return ERR_PTR(err); 172025d89c2SHerbert Xu 173025d89c2SHerbert Xu out: 174025d89c2SHerbert Xu return p; 175025d89c2SHerbert Xu } 176025d89c2SHerbert Xu 1776db6f0eaSFelix Fietkau static void maybe_deliver_addr(struct net_bridge_port *p, struct sk_buff *skb, 1786db6f0eaSFelix Fietkau const unsigned char *addr, bool local_orig) 1796db6f0eaSFelix Fietkau { 1806db6f0eaSFelix Fietkau struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev; 1816db6f0eaSFelix Fietkau const unsigned char *src = eth_hdr(skb)->h_source; 1826db6f0eaSFelix Fietkau 1836db6f0eaSFelix Fietkau if (!should_deliver(p, skb)) 1846db6f0eaSFelix Fietkau return; 1856db6f0eaSFelix Fietkau 1866db6f0eaSFelix Fietkau /* Even with hairpin, no soliloquies - prevent breaking IPv6 DAD */ 1876db6f0eaSFelix Fietkau if (skb->dev == p->dev && ether_addr_equal(src, addr)) 1886db6f0eaSFelix Fietkau return; 1896db6f0eaSFelix Fietkau 1906db6f0eaSFelix Fietkau skb = skb_copy(skb, GFP_ATOMIC); 1916db6f0eaSFelix Fietkau if (!skb) { 1926db6f0eaSFelix Fietkau dev->stats.tx_dropped++; 1936db6f0eaSFelix Fietkau return; 1946db6f0eaSFelix Fietkau } 1956db6f0eaSFelix Fietkau 1966db6f0eaSFelix Fietkau if (!is_broadcast_ether_addr(addr)) 1976db6f0eaSFelix Fietkau memcpy(eth_hdr(skb)->h_dest, addr, ETH_ALEN); 1986db6f0eaSFelix Fietkau 1996db6f0eaSFelix Fietkau __br_forward(p, skb, local_orig); 2006db6f0eaSFelix Fietkau } 2016db6f0eaSFelix Fietkau 20237b090e6SNikolay Aleksandrov /* called under rcu_read_lock */ 20337b090e6SNikolay Aleksandrov void br_flood(struct net_bridge *br, struct sk_buff *skb, 2048addd5e7SNikolay Aleksandrov enum br_pkt_type pkt_type, bool local_rcv, bool local_orig) 2051da177e4SLinus Torvalds { 2061080ab95SNikolay Aleksandrov u8 igmp_type = br_multicast_igmp_type(skb); 20737b090e6SNikolay Aleksandrov struct net_bridge_port *prev = NULL; 2081080ab95SNikolay Aleksandrov struct net_bridge_port *p; 2091da177e4SLinus Torvalds 2101da177e4SLinus Torvalds list_for_each_entry_rcu(p, &br->port_list, list) { 211867a5943SVlad Yasevich /* Do not flood unicast traffic to ports that turn it off */ 2128addd5e7SNikolay Aleksandrov if (pkt_type == BR_PKT_UNICAST && !(p->flags & BR_FLOOD)) 213867a5943SVlad Yasevich continue; 214b6cb5ac8SNikolay Aleksandrov if (pkt_type == BR_PKT_MULTICAST && 215b6cb5ac8SNikolay Aleksandrov !(p->flags & BR_MCAST_FLOOD)) 216b6cb5ac8SNikolay Aleksandrov continue; 21795850116SKyeyoon Park 21895850116SKyeyoon Park /* Do not flood to ports that enable proxy ARP */ 21995850116SKyeyoon Park if (p->flags & BR_PROXYARP) 22095850116SKyeyoon Park continue; 221842a9ae0SJouni Malinen if ((p->flags & BR_PROXYARP_WIFI) && 222842a9ae0SJouni Malinen BR_INPUT_SKB_CB(skb)->proxyarp_replied) 223842a9ae0SJouni Malinen continue; 22495850116SKyeyoon Park 22537b090e6SNikolay Aleksandrov prev = maybe_deliver(prev, p, skb, local_orig); 226025d89c2SHerbert Xu if (IS_ERR(prev)) 227b33084beSHerbert Xu goto out; 2281080ab95SNikolay Aleksandrov if (prev == p) 229a65056ecSNikolay Aleksandrov br_multicast_count(p->br, p, skb, igmp_type, 2301080ab95SNikolay Aleksandrov BR_MCAST_DIR_TX); 2311da177e4SLinus Torvalds } 2321da177e4SLinus Torvalds 233b33084beSHerbert Xu if (!prev) 234b33084beSHerbert Xu goto out; 235b33084beSHerbert Xu 236b35c5f63SNikolay Aleksandrov if (local_rcv) 23737b090e6SNikolay Aleksandrov deliver_clone(prev, skb, local_orig); 238025d89c2SHerbert Xu else 23937b090e6SNikolay Aleksandrov __br_forward(prev, skb, local_orig); 2401da177e4SLinus Torvalds return; 2411da177e4SLinus Torvalds 242b33084beSHerbert Xu out: 243b35c5f63SNikolay Aleksandrov if (!local_rcv) 2441da177e4SLinus Torvalds kfree_skb(skb); 2451da177e4SLinus Torvalds } 2461da177e4SLinus Torvalds 2475cb5e947SHerbert Xu #ifdef CONFIG_BRIDGE_IGMP_SNOOPING 2485cb5e947SHerbert Xu /* called with rcu_read_lock */ 24937b090e6SNikolay Aleksandrov void br_multicast_flood(struct net_bridge_mdb_entry *mdst, 250b35c5f63SNikolay Aleksandrov struct sk_buff *skb, 25137b090e6SNikolay Aleksandrov bool local_rcv, bool local_orig) 2525cb5e947SHerbert Xu { 2535cb5e947SHerbert Xu struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev; 2541080ab95SNikolay Aleksandrov u8 igmp_type = br_multicast_igmp_type(skb); 2555cb5e947SHerbert Xu struct net_bridge *br = netdev_priv(dev); 256afe0159dSstephen hemminger struct net_bridge_port *prev = NULL; 2575cb5e947SHerbert Xu struct net_bridge_port_group *p; 2585cb5e947SHerbert Xu struct hlist_node *rp; 2595cb5e947SHerbert Xu 260e8051688SEric Dumazet rp = rcu_dereference(hlist_first_rcu(&br->router_list)); 26183f6a740Sstephen hemminger p = mdst ? rcu_dereference(mdst->ports) : NULL; 2625cb5e947SHerbert Xu while (p || rp) { 263afe0159dSstephen hemminger struct net_bridge_port *port, *lport, *rport; 264afe0159dSstephen hemminger 2655cb5e947SHerbert Xu lport = p ? p->port : NULL; 2665cb5e947SHerbert Xu rport = rp ? hlist_entry(rp, struct net_bridge_port, rlist) : 2675cb5e947SHerbert Xu NULL; 2685cb5e947SHerbert Xu 2696db6f0eaSFelix Fietkau if ((unsigned long)lport > (unsigned long)rport) { 2706db6f0eaSFelix Fietkau port = lport; 2716db6f0eaSFelix Fietkau 2726db6f0eaSFelix Fietkau if (port->flags & BR_MULTICAST_TO_UNICAST) { 2736db6f0eaSFelix Fietkau maybe_deliver_addr(lport, skb, p->eth_addr, 2746db6f0eaSFelix Fietkau local_orig); 2756db6f0eaSFelix Fietkau goto delivered; 2766db6f0eaSFelix Fietkau } 2776db6f0eaSFelix Fietkau } else { 2786db6f0eaSFelix Fietkau port = rport; 2796db6f0eaSFelix Fietkau } 2805cb5e947SHerbert Xu 28137b090e6SNikolay Aleksandrov prev = maybe_deliver(prev, port, skb, local_orig); 2826db6f0eaSFelix Fietkau delivered: 2835cb5e947SHerbert Xu if (IS_ERR(prev)) 2845cb5e947SHerbert Xu goto out; 2851080ab95SNikolay Aleksandrov if (prev == port) 286a65056ecSNikolay Aleksandrov br_multicast_count(port->br, port, skb, igmp_type, 2871080ab95SNikolay Aleksandrov BR_MCAST_DIR_TX); 2885cb5e947SHerbert Xu 2895cb5e947SHerbert Xu if ((unsigned long)lport >= (unsigned long)port) 29083f6a740Sstephen hemminger p = rcu_dereference(p->next); 2915cb5e947SHerbert Xu if ((unsigned long)rport >= (unsigned long)port) 292e8051688SEric Dumazet rp = rcu_dereference(hlist_next_rcu(rp)); 2935cb5e947SHerbert Xu } 2945cb5e947SHerbert Xu 2955cb5e947SHerbert Xu if (!prev) 2965cb5e947SHerbert Xu goto out; 2975cb5e947SHerbert Xu 298b35c5f63SNikolay Aleksandrov if (local_rcv) 29937b090e6SNikolay Aleksandrov deliver_clone(prev, skb, local_orig); 3005cb5e947SHerbert Xu else 30137b090e6SNikolay Aleksandrov __br_forward(prev, skb, local_orig); 3025cb5e947SHerbert Xu return; 3035cb5e947SHerbert Xu 3045cb5e947SHerbert Xu out: 305b35c5f63SNikolay Aleksandrov if (!local_rcv) 3065cb5e947SHerbert Xu kfree_skb(skb); 3075cb5e947SHerbert Xu } 3085cb5e947SHerbert Xu #endif 309