3 * Linux ethernet bridge
6 * Lennert Buytenhek <buytenh@gnu.org>
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.
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <linux/kernel.h>
17 #include <linux/netdevice.h>
18 #include <linux/netpoll.h>
19 #include <linux/skbuff.h>
20 #include <linux/if_vlan.h>
21 #include <linux/netfilter_bridge.h>
22 #include "br_private.h"
24 static int deliver_clone(const struct net_bridge_port *prev,
26 void (*__packet_hook)(const struct net_bridge_port *p,
27 struct sk_buff *skb));
29 /* Don't forward packets to originating port or forwarding disabled */
30 static inline int should_deliver(const struct net_bridge_port *p,
31 const struct sk_buff *skb)
33 struct net_bridge_vlan_group *vg;
35 vg = nbp_vlan_group_rcu(p);
36 return ((p->flags & BR_HAIRPIN_MODE) || skb->dev != p->dev) &&
37 br_allowed_egress(vg, skb) && p->state == BR_STATE_FORWARDING;
40 int br_dev_queue_push_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
42 if (!is_skb_forwardable(skb->dev, skb))
45 skb_push(skb, ETH_HLEN);
46 br_drop_fake_rtable(skb);
48 if (skb->ip_summed == CHECKSUM_PARTIAL &&
49 (skb->protocol == htons(ETH_P_8021Q) ||
50 skb->protocol == htons(ETH_P_8021AD))) {
53 if (!__vlan_get_protocol(skb, skb->protocol, &depth))
56 skb_set_network_header(skb, depth);
67 EXPORT_SYMBOL_GPL(br_dev_queue_push_xmit);
69 int br_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
71 return NF_HOOK(NFPROTO_BRIDGE, NF_BR_POST_ROUTING,
72 net, sk, skb, NULL, skb->dev,
73 br_dev_queue_push_xmit);
76 EXPORT_SYMBOL_GPL(br_forward_finish);
78 static void __br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
80 struct net_bridge_vlan_group *vg;
82 vg = nbp_vlan_group_rcu(to);
83 skb = br_handle_vlan(to->br, vg, skb);
89 if (unlikely(netpoll_tx_running(to->br->dev))) {
90 if (!is_skb_forwardable(skb->dev, skb))
93 skb_push(skb, ETH_HLEN);
94 br_netpoll_send_skb(to, skb);
99 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
100 dev_net(skb->dev), NULL, skb,NULL, skb->dev,
104 static void __br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
106 struct net_bridge_vlan_group *vg;
107 struct net_device *indev;
109 if (skb_warn_if_lro(skb)) {
114 vg = nbp_vlan_group_rcu(to);
115 skb = br_handle_vlan(to->br, vg, skb);
121 skb_forward_csum(skb);
123 NF_HOOK(NFPROTO_BRIDGE, NF_BR_FORWARD,
124 dev_net(indev), NULL, skb, indev, skb->dev,
128 /* called with rcu_read_lock */
129 void br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
131 if (to && should_deliver(to, skb)) {
132 __br_deliver(to, skb);
138 EXPORT_SYMBOL_GPL(br_deliver);
140 /* called with rcu_read_lock */
141 void br_forward(const struct net_bridge_port *to, struct sk_buff *skb, struct sk_buff *skb0)
143 if (to && should_deliver(to, skb)) {
145 deliver_clone(to, skb, __br_forward);
147 __br_forward(to, skb);
155 static int deliver_clone(const struct net_bridge_port *prev,
157 void (*__packet_hook)(const struct net_bridge_port *p,
158 struct sk_buff *skb))
160 struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
162 skb = skb_clone(skb, GFP_ATOMIC);
164 dev->stats.tx_dropped++;
168 __packet_hook(prev, skb);
172 static struct net_bridge_port *maybe_deliver(
173 struct net_bridge_port *prev, struct net_bridge_port *p,
175 void (*__packet_hook)(const struct net_bridge_port *p,
176 struct sk_buff *skb))
180 if (!should_deliver(p, skb))
186 err = deliver_clone(prev, skb, __packet_hook);
194 /* called under bridge lock */
195 static void br_flood(struct net_bridge *br, struct sk_buff *skb,
196 struct sk_buff *skb0,
197 void (*__packet_hook)(const struct net_bridge_port *p,
198 struct sk_buff *skb),
201 u8 igmp_type = br_multicast_igmp_type(skb);
202 struct net_bridge_port *prev;
203 struct net_bridge_port *p;
207 list_for_each_entry_rcu(p, &br->port_list, list) {
208 /* Do not flood unicast traffic to ports that turn it off */
209 if (unicast && !(p->flags & BR_FLOOD))
212 /* Do not flood to ports that enable proxy ARP */
213 if (p->flags & BR_PROXYARP)
215 if ((p->flags & BR_PROXYARP_WIFI) &&
216 BR_INPUT_SKB_CB(skb)->proxyarp_replied)
219 prev = maybe_deliver(prev, p, skb, __packet_hook);
223 br_multicast_count(p->br, p, skb, igmp_type,
231 deliver_clone(prev, skb, __packet_hook);
233 __packet_hook(prev, skb);
242 /* called with rcu_read_lock */
243 void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb, bool unicast)
245 br_flood(br, skb, NULL, __br_deliver, unicast);
248 /* called under bridge lock */
249 void br_flood_forward(struct net_bridge *br, struct sk_buff *skb,
250 struct sk_buff *skb2, bool unicast)
252 br_flood(br, skb, skb2, __br_forward, unicast);
255 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
256 /* called with rcu_read_lock */
257 static void br_multicast_flood(struct net_bridge_mdb_entry *mdst,
258 struct sk_buff *skb, struct sk_buff *skb0,
259 void (*__packet_hook)(
260 const struct net_bridge_port *p,
261 struct sk_buff *skb))
263 struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
264 u8 igmp_type = br_multicast_igmp_type(skb);
265 struct net_bridge *br = netdev_priv(dev);
266 struct net_bridge_port *prev = NULL;
267 struct net_bridge_port_group *p;
268 struct hlist_node *rp;
270 rp = rcu_dereference(hlist_first_rcu(&br->router_list));
271 p = mdst ? rcu_dereference(mdst->ports) : NULL;
273 struct net_bridge_port *port, *lport, *rport;
275 lport = p ? p->port : NULL;
276 rport = rp ? hlist_entry(rp, struct net_bridge_port, rlist) :
279 port = (unsigned long)lport > (unsigned long)rport ?
282 prev = maybe_deliver(prev, port, skb, __packet_hook);
286 br_multicast_count(port->br, port, skb, igmp_type,
289 if ((unsigned long)lport >= (unsigned long)port)
290 p = rcu_dereference(p->next);
291 if ((unsigned long)rport >= (unsigned long)port)
292 rp = rcu_dereference(hlist_next_rcu(rp));
299 deliver_clone(prev, skb, __packet_hook);
301 __packet_hook(prev, skb);
309 /* called with rcu_read_lock */
310 void br_multicast_deliver(struct net_bridge_mdb_entry *mdst,
313 br_multicast_flood(mdst, skb, NULL, __br_deliver);
316 /* called with rcu_read_lock */
317 void br_multicast_forward(struct net_bridge_mdb_entry *mdst,
318 struct sk_buff *skb, struct sk_buff *skb2)
320 br_multicast_flood(mdst, skb, skb2, __br_forward);