1 #ifndef __LINUX_BRIDGE_NETFILTER_H
2 #define __LINUX_BRIDGE_NETFILTER_H
3 
4 /* bridge-specific defines for netfilter.
5  */
6 
7 #include <linux/netfilter.h>
8 #include <linux/if_ether.h>
9 #include <linux/if_vlan.h>
10 
11 /* Bridge Hooks */
12 /* After promisc drops, checksum checks. */
13 #define NF_BR_PRE_ROUTING	0
14 /* If the packet is destined for this box. */
15 #define NF_BR_LOCAL_IN		1
16 /* If the packet is destined for another interface. */
17 #define NF_BR_FORWARD		2
18 /* Packets coming from a local process. */
19 #define NF_BR_LOCAL_OUT		3
20 /* Packets about to hit the wire. */
21 #define NF_BR_POST_ROUTING	4
22 /* Not really a hook, but used for the ebtables broute table */
23 #define NF_BR_BROUTING		5
24 #define NF_BR_NUMHOOKS		6
25 
26 #ifdef __KERNEL__
27 
28 enum nf_br_hook_priorities {
29 	NF_BR_PRI_FIRST = INT_MIN,
30 	NF_BR_PRI_NAT_DST_BRIDGED = -300,
31 	NF_BR_PRI_FILTER_BRIDGED = -200,
32 	NF_BR_PRI_BRNF = 0,
33 	NF_BR_PRI_NAT_DST_OTHER = 100,
34 	NF_BR_PRI_FILTER_OTHER = 200,
35 	NF_BR_PRI_NAT_SRC = 300,
36 	NF_BR_PRI_LAST = INT_MAX,
37 };
38 
39 #ifdef CONFIG_BRIDGE_NETFILTER
40 
41 #define BRNF_PKT_TYPE			0x01
42 #define BRNF_BRIDGED_DNAT		0x02
43 #define BRNF_DONT_TAKE_PARENT		0x04
44 #define BRNF_BRIDGED			0x08
45 #define BRNF_NF_BRIDGE_PREROUTING	0x10
46 
47 
48 /* Only used in br_forward.c */
49 extern int nf_bridge_copy_header(struct sk_buff *skb);
50 static inline int nf_bridge_maybe_copy_header(struct sk_buff *skb)
51 {
52 	if (skb->nf_bridge)
53 		return nf_bridge_copy_header(skb);
54   	return 0;
55 }
56 
57 /* This is called by the IP fragmenting code and it ensures there is
58  * enough room for the encapsulating header (if there is one). */
59 static inline int nf_bridge_pad(const struct sk_buff *skb)
60 {
61  	return (skb->nf_bridge && skb->protocol == htons(ETH_P_8021Q))
62 		? VLAN_HLEN : 0;
63 }
64 
65 struct bridge_skb_cb {
66 	union {
67 		__be32 ipv4;
68 	} daddr;
69 };
70 
71 #else
72 #define nf_bridge_maybe_copy_header(skb)	(0)
73 #define nf_bridge_pad(skb)			(0)
74 #endif /* CONFIG_BRIDGE_NETFILTER */
75 
76 #endif /* __KERNEL__ */
77 #endif
78