nf_conntrack_tcp.h revision 874ab9233eeddb85fd2dd85131c145bde75da39a 
1#ifndef _NF_CONNTRACK_TCP_H
2#define _NF_CONNTRACK_TCP_H
3/* TCP tracking. */
4
5#include <linux/types.h>
6
7/* This is exposed to userspace (ctnetlink) */
8enum tcp_conntrack {
9	TCP_CONNTRACK_NONE,
10	TCP_CONNTRACK_SYN_SENT,
11	TCP_CONNTRACK_SYN_RECV,
12	TCP_CONNTRACK_ESTABLISHED,
13	TCP_CONNTRACK_FIN_WAIT,
14	TCP_CONNTRACK_CLOSE_WAIT,
15	TCP_CONNTRACK_LAST_ACK,
16	TCP_CONNTRACK_TIME_WAIT,
17	TCP_CONNTRACK_CLOSE,
18	TCP_CONNTRACK_LISTEN,	/* obsolete */
19#define TCP_CONNTRACK_SYN_SENT2	TCP_CONNTRACK_LISTEN
20	TCP_CONNTRACK_MAX,
21	TCP_CONNTRACK_IGNORE
22};
23
24/* Window scaling is advertised by the sender */
25#define IP_CT_TCP_FLAG_WINDOW_SCALE		0x01
26
27/* SACK is permitted by the sender */
28#define IP_CT_TCP_FLAG_SACK_PERM		0x02
29
30/* This sender sent FIN first */
31#define IP_CT_TCP_FLAG_CLOSE_INIT		0x04
32
33/* Be liberal in window checking */
34#define IP_CT_TCP_FLAG_BE_LIBERAL		0x08
35
36/* Has unacknowledged data */
37#define IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED	0x10
38
39struct nf_ct_tcp_flags {
40	__u8 flags;
41	__u8 mask;
42};
43
44#ifdef __KERNEL__
45
46struct ip_ct_tcp_state {
47	u_int32_t	td_end;		/* max of seq + len */
48	u_int32_t	td_maxend;	/* max of ack + max(win, 1) */
49	u_int32_t	td_maxwin;	/* max(win) */
50	u_int8_t	td_scale;	/* window scale factor */
51	u_int8_t	flags;		/* per direction options */
52};
53
54struct ip_ct_tcp
55{
56	struct ip_ct_tcp_state seen[2];	/* connection parameters per direction */
57	u_int8_t	state;		/* state of the connection (enum tcp_conntrack) */
58	/* For detecting stale connections */
59	u_int8_t	last_dir;	/* Direction of the last packet (enum ip_conntrack_dir) */
60	u_int8_t	retrans;	/* Number of retransmitted packets */
61	u_int8_t	last_index;	/* Index of the last packet */
62	u_int32_t	last_seq;	/* Last sequence number seen in dir */
63	u_int32_t	last_ack;	/* Last sequence number seen in opposite dir */
64	u_int32_t	last_end;	/* Last seq + len */
65	u_int16_t	last_win;	/* Last window advertisement seen in dir */
66};
67
68#endif /* __KERNEL__ */
69
70#endif /* _NF_CONNTRACK_TCP_H */
71