2 * Copyright (C)2003,2004 USAGI/WIDE Project
4 * Header for use in defining a given L3 protocol for connection tracking.
7 * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
9 * Derived from include/netfilter_ipv4/ip_conntrack_protocol.h
12 #ifndef _NF_CONNTRACK_L3PROTO_H
13 #define _NF_CONNTRACK_L3PROTO_H
14 #include <linux/netlink.h>
15 #include <linux/seq_file.h>
16 #include <net/netfilter/nf_conntrack.h>
18 struct nf_conntrack_l3proto
20 /* L3 Protocol Family number. ex) PF_INET */
27 * Try to fill in the third arg: nhoff is offset of l3 proto
28 * hdr. Return true if possible.
30 int (*pkt_to_tuple)(const struct sk_buff *skb, unsigned int nhoff,
31 struct nf_conntrack_tuple *tuple);
34 * Invert the per-proto part of the tuple: ie. turn xmit into reply.
35 * Some packets can't be inverted: return 0 in that case.
37 int (*invert_tuple)(struct nf_conntrack_tuple *inverse,
38 const struct nf_conntrack_tuple *orig);
40 /* Print out the per-protocol part of the tuple. */
41 int (*print_tuple)(struct seq_file *s,
42 const struct nf_conntrack_tuple *);
44 /* Print out the private part of the conntrack. */
45 int (*print_conntrack)(struct seq_file *s, const struct nf_conn *);
47 /* Returns verdict for packet, or -1 for invalid. */
48 int (*packet)(struct nf_conn *conntrack,
49 const struct sk_buff *skb,
50 enum ip_conntrack_info ctinfo);
53 * Called when a new connection for this protocol found;
54 * returns TRUE if it's OK. If so, packet() called next.
56 int (*new)(struct nf_conn *conntrack, const struct sk_buff *skb);
59 * Called before tracking.
60 * *dataoff: offset of protocol header (TCP, UDP,...) in skb
61 * *protonum: protocol number
63 int (*get_l4proto)(const struct sk_buff *skb, unsigned int nhoff,
64 unsigned int *dataoff, u_int8_t *protonum);
66 int (*tuple_to_nfattr)(struct sk_buff *skb,
67 const struct nf_conntrack_tuple *t);
69 int (*nfattr_to_tuple)(struct nlattr *tb[],
70 struct nf_conntrack_tuple *t);
73 struct ctl_table_header *ctl_table_header;
74 struct ctl_table *ctl_table_path;
75 struct ctl_table *ctl_table;
76 #endif /* CONFIG_SYSCTL */
78 /* Module (if any) which this is connected to. */
82 extern struct nf_conntrack_l3proto *nf_ct_l3protos[AF_MAX];
84 /* Protocol registration. */
85 extern int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto);
86 extern void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto);
87 extern struct nf_conntrack_l3proto *nf_ct_l3proto_find_get(u_int16_t l3proto);
88 extern void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p);
90 /* Existing built-in protocols */
91 extern struct nf_conntrack_l3proto nf_conntrack_l3proto_generic;
93 static inline struct nf_conntrack_l3proto *
94 __nf_ct_l3proto_find(u_int16_t l3proto)
96 if (unlikely(l3proto >= AF_MAX))
97 return &nf_conntrack_l3proto_generic;
98 return rcu_dereference(nf_ct_l3protos[l3proto]);
101 #endif /*_NF_CONNTRACK_L3PROTO_H*/