alistair23-linux/include/linux/netfilter/nf_conntrack_tcp.h
Pablo Neira Ayuso c8e2078cfe [NETFILTER]: ctnetlink: add support for internal tcp connection tracking flags handling
This patch let userspace programs set the IP_CT_TCP_BE_LIBERAL flag to
force the pickup of established connections.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:57 -07:00

65 lines
1.7 KiB
C

#ifndef _NF_CONNTRACK_TCP_H
#define _NF_CONNTRACK_TCP_H
/* TCP tracking. */
/* This is exposed to userspace (ctnetlink) */
enum tcp_conntrack {
TCP_CONNTRACK_NONE,
TCP_CONNTRACK_SYN_SENT,
TCP_CONNTRACK_SYN_RECV,
TCP_CONNTRACK_ESTABLISHED,
TCP_CONNTRACK_FIN_WAIT,
TCP_CONNTRACK_CLOSE_WAIT,
TCP_CONNTRACK_LAST_ACK,
TCP_CONNTRACK_TIME_WAIT,
TCP_CONNTRACK_CLOSE,
TCP_CONNTRACK_LISTEN,
TCP_CONNTRACK_MAX,
TCP_CONNTRACK_IGNORE
};
/* Window scaling is advertised by the sender */
#define IP_CT_TCP_FLAG_WINDOW_SCALE 0x01
/* SACK is permitted by the sender */
#define IP_CT_TCP_FLAG_SACK_PERM 0x02
/* This sender sent FIN first */
#define IP_CT_TCP_FLAG_CLOSE_INIT 0x04
/* Be liberal in window checking */
#define IP_CT_TCP_FLAG_BE_LIBERAL 0x08
struct nf_ct_tcp_flags {
u_int8_t flags;
u_int8_t mask;
};
#ifdef __KERNEL__
struct ip_ct_tcp_state {
u_int32_t td_end; /* max of seq + len */
u_int32_t td_maxend; /* max of ack + max(win, 1) */
u_int32_t td_maxwin; /* max(win) */
u_int8_t td_scale; /* window scale factor */
u_int8_t flags; /* per direction options */
};
struct ip_ct_tcp
{
struct ip_ct_tcp_state seen[2]; /* connection parameters per direction */
u_int8_t state; /* state of the connection (enum tcp_conntrack) */
/* For detecting stale connections */
u_int8_t last_dir; /* Direction of the last packet (enum ip_conntrack_dir) */
u_int8_t retrans; /* Number of retransmitted packets */
u_int8_t last_index; /* Index of the last packet */
u_int32_t last_seq; /* Last sequence number seen in dir */
u_int32_t last_ack; /* Last sequence number seen in opposite dir */
u_int32_t last_end; /* Last seq + len */
u_int16_t last_win; /* Last window advertisement seen in dir */
};
#endif /* __KERNEL__ */
#endif /* _NF_CONNTRACK_TCP_H */