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git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - net/bridge/br_forward.c
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 return ((p
->flags
& BR_HAIRPIN_MODE
) || skb
->dev
!= p
->dev
) &&
34 br_allowed_egress(p
->br
, nbp_get_vlan_info(p
), skb
) &&
35 p
->state
== BR_STATE_FORWARDING
;
38 int br_dev_queue_push_xmit(struct sk_buff
*skb
)
40 /* ip_fragment doesn't copy the MAC header */
41 if (nf_bridge_maybe_copy_header(skb
) ||
42 !is_skb_forwardable(skb
->dev
, skb
)) {
45 skb_push(skb
, ETH_HLEN
);
46 br_drop_fake_rtable(skb
);
52 EXPORT_SYMBOL_GPL(br_dev_queue_push_xmit
);
54 int br_forward_finish(struct sk_buff
*skb
)
56 return NF_HOOK(NFPROTO_BRIDGE
, NF_BR_POST_ROUTING
, skb
, NULL
, skb
->dev
,
57 br_dev_queue_push_xmit
);
60 EXPORT_SYMBOL_GPL(br_forward_finish
);
62 static void __br_deliver(const struct net_bridge_port
*to
, struct sk_buff
*skb
)
64 skb
= br_handle_vlan(to
->br
, nbp_get_vlan_info(to
), skb
);
70 if (unlikely(netpoll_tx_running(to
->br
->dev
))) {
71 if (!is_skb_forwardable(skb
->dev
, skb
))
74 skb_push(skb
, ETH_HLEN
);
75 br_netpoll_send_skb(to
, skb
);
80 NF_HOOK(NFPROTO_BRIDGE
, NF_BR_LOCAL_OUT
, skb
, NULL
, skb
->dev
,
84 static void __br_forward(const struct net_bridge_port
*to
, struct sk_buff
*skb
)
86 struct net_device
*indev
;
88 if (skb_warn_if_lro(skb
)) {
93 skb
= br_handle_vlan(to
->br
, nbp_get_vlan_info(to
), skb
);
99 skb_forward_csum(skb
);
101 NF_HOOK(NFPROTO_BRIDGE
, NF_BR_FORWARD
, skb
, indev
, skb
->dev
,
105 /* called with rcu_read_lock */
106 void br_deliver(const struct net_bridge_port
*to
, struct sk_buff
*skb
)
108 if (to
&& should_deliver(to
, skb
)) {
109 __br_deliver(to
, skb
);
115 EXPORT_SYMBOL_GPL(br_deliver
);
117 /* called with rcu_read_lock */
118 void br_forward(const struct net_bridge_port
*to
, struct sk_buff
*skb
, struct sk_buff
*skb0
)
120 if (should_deliver(to
, skb
)) {
122 deliver_clone(to
, skb
, __br_forward
);
124 __br_forward(to
, skb
);
132 static int deliver_clone(const struct net_bridge_port
*prev
,
134 void (*__packet_hook
)(const struct net_bridge_port
*p
,
135 struct sk_buff
*skb
))
137 struct net_device
*dev
= BR_INPUT_SKB_CB(skb
)->brdev
;
139 skb
= skb_clone(skb
, GFP_ATOMIC
);
141 dev
->stats
.tx_dropped
++;
145 __packet_hook(prev
, skb
);
149 static struct net_bridge_port
*maybe_deliver(
150 struct net_bridge_port
*prev
, struct net_bridge_port
*p
,
152 void (*__packet_hook
)(const struct net_bridge_port
*p
,
153 struct sk_buff
*skb
))
157 if (!should_deliver(p
, skb
))
163 err
= deliver_clone(prev
, skb
, __packet_hook
);
171 /* called under bridge lock */
172 static void br_flood(struct net_bridge
*br
, struct sk_buff
*skb
,
173 struct sk_buff
*skb0
,
174 void (*__packet_hook
)(const struct net_bridge_port
*p
,
175 struct sk_buff
*skb
),
178 struct net_bridge_port
*p
;
179 struct net_bridge_port
*prev
;
183 list_for_each_entry_rcu(p
, &br
->port_list
, list
) {
184 /* Do not flood unicast traffic to ports that turn it off */
185 if (unicast
&& !(p
->flags
& BR_FLOOD
))
188 /* Do not flood to ports that enable proxy ARP */
189 if (p
->flags
& BR_PROXYARP
)
192 prev
= maybe_deliver(prev
, p
, skb
, __packet_hook
);
201 deliver_clone(prev
, skb
, __packet_hook
);
203 __packet_hook(prev
, skb
);
212 /* called with rcu_read_lock */
213 void br_flood_deliver(struct net_bridge
*br
, struct sk_buff
*skb
, bool unicast
)
215 br_flood(br
, skb
, NULL
, __br_deliver
, unicast
);
218 /* called under bridge lock */
219 void br_flood_forward(struct net_bridge
*br
, struct sk_buff
*skb
,
220 struct sk_buff
*skb2
, bool unicast
)
222 br_flood(br
, skb
, skb2
, __br_forward
, unicast
);
225 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
226 /* called with rcu_read_lock */
227 static void br_multicast_flood(struct net_bridge_mdb_entry
*mdst
,
228 struct sk_buff
*skb
, struct sk_buff
*skb0
,
229 void (*__packet_hook
)(
230 const struct net_bridge_port
*p
,
231 struct sk_buff
*skb
))
233 struct net_device
*dev
= BR_INPUT_SKB_CB(skb
)->brdev
;
234 struct net_bridge
*br
= netdev_priv(dev
);
235 struct net_bridge_port
*prev
= NULL
;
236 struct net_bridge_port_group
*p
;
237 struct hlist_node
*rp
;
239 rp
= rcu_dereference(hlist_first_rcu(&br
->router_list
));
240 p
= mdst
? rcu_dereference(mdst
->ports
) : NULL
;
242 struct net_bridge_port
*port
, *lport
, *rport
;
244 lport
= p
? p
->port
: NULL
;
245 rport
= rp
? hlist_entry(rp
, struct net_bridge_port
, rlist
) :
248 port
= (unsigned long)lport
> (unsigned long)rport
?
251 prev
= maybe_deliver(prev
, port
, skb
, __packet_hook
);
255 if ((unsigned long)lport
>= (unsigned long)port
)
256 p
= rcu_dereference(p
->next
);
257 if ((unsigned long)rport
>= (unsigned long)port
)
258 rp
= rcu_dereference(hlist_next_rcu(rp
));
265 deliver_clone(prev
, skb
, __packet_hook
);
267 __packet_hook(prev
, skb
);
275 /* called with rcu_read_lock */
276 void br_multicast_deliver(struct net_bridge_mdb_entry
*mdst
,
279 br_multicast_flood(mdst
, skb
, NULL
, __br_deliver
);
282 /* called with rcu_read_lock */
283 void br_multicast_forward(struct net_bridge_mdb_entry
*mdst
,
284 struct sk_buff
*skb
, struct sk_buff
*skb2
)
286 br_multicast_flood(mdst
, skb
, skb2
, __br_forward
);