1 /*
2  * This header is used to share core functionality between the
3  * standalone connection tracking module, and the compatibility layer's use
4  * of connection tracking.
5  *
6  * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
7  *	- generalize L3 protocol dependent part.
8  *
9  * Derived from include/linux/netfiter_ipv4/ip_conntrack_core.h
10  */
11 
12 #ifndef _NF_CONNTRACK_CORE_H
13 #define _NF_CONNTRACK_CORE_H
14 
15 #include <linux/netfilter.h>
16 #include <net/netfilter/nf_conntrack_l3proto.h>
17 #include <net/netfilter/nf_conntrack_l4proto.h>
18 #include <net/netfilter/nf_conntrack_ecache.h>
19 
20 /* This header is used to share core functionality between the
21    standalone connection tracking module, and the compatibility layer's use
22    of connection tracking. */
23 extern unsigned int nf_conntrack_in(struct net *net,
24 				    u_int8_t pf,
25 				    unsigned int hooknum,
26 				    struct sk_buff *skb);
27 
28 extern int nf_conntrack_init(struct net *net);
29 extern void nf_conntrack_cleanup(struct net *net);
30 
31 extern int nf_conntrack_proto_init(void);
32 extern void nf_conntrack_proto_fini(void);
33 
34 extern bool
35 nf_ct_get_tuple(const struct sk_buff *skb,
36 		unsigned int nhoff,
37 		unsigned int dataoff,
38 		u_int16_t l3num,
39 		u_int8_t protonum,
40 		struct nf_conntrack_tuple *tuple,
41 		const struct nf_conntrack_l3proto *l3proto,
42 		const struct nf_conntrack_l4proto *l4proto);
43 
44 extern bool
45 nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse,
46 		   const struct nf_conntrack_tuple *orig,
47 		   const struct nf_conntrack_l3proto *l3proto,
48 		   const struct nf_conntrack_l4proto *l4proto);
49 
50 /* Find a connection corresponding to a tuple. */
51 extern struct nf_conntrack_tuple_hash *
52 nf_conntrack_find_get(struct net *net, u16 zone,
53 		      const struct nf_conntrack_tuple *tuple);
54 
55 extern int __nf_conntrack_confirm(struct sk_buff *skb);
56 
57 /* Confirm a connection: returns NF_DROP if packet must be dropped. */
nf_conntrack_confirm(struct sk_buff * skb)58 static inline int nf_conntrack_confirm(struct sk_buff *skb)
59 {
60 	struct nf_conn *ct = (struct nf_conn *)skb->nfct;
61 	int ret = NF_ACCEPT;
62 
63 	if (ct && !nf_ct_is_untracked(ct)) {
64 		if (!nf_ct_is_confirmed(ct))
65 			ret = __nf_conntrack_confirm(skb);
66 		if (likely(ret == NF_ACCEPT))
67 			nf_ct_deliver_cached_events(ct);
68 	}
69 	return ret;
70 }
71 
72 int
73 print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple,
74             const struct nf_conntrack_l3proto *l3proto,
75             const struct nf_conntrack_l4proto *proto);
76 
77 extern spinlock_t nf_conntrack_lock ;
78 
79 #endif /* _NF_CONNTRACK_CORE_H */
80