root/include/uapi/linux/netfilter/nf_conntrack_tcp.h

INCLUDED FROM

#ifndef _UAPI_NF_CONNTRACK_TCP_H
#define _UAPI_NF_CONNTRACK_TCP_H
/* TCP tracking. */

#include <linux/types.h>

/* 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,   /* obsolete */
#define TCP_CONNTRACK_SYN_SENT2 TCP_CONNTRACK_LISTEN
        TCP_CONNTRACK_MAX,
        TCP_CONNTRACK_IGNORE,
        TCP_CONNTRACK_RETRANS,
        TCP_CONNTRACK_UNACK,
        TCP_CONNTRACK_TIMEOUT_MAX
};

/* 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

/* Has unacknowledged data */
#define IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED      0x10

/* The field td_maxack has been set */
#define IP_CT_TCP_FLAG_MAXACK_SET               0x20

struct nf_ct_tcp_flags {
        __u8 flags;
        __u8 mask;
};


#endif /* _UAPI_NF_CONNTRACK_TCP_H */