1 #ifndef _NF_CONNTRACK_TCP_H 2 #define _NF_CONNTRACK_TCP_H 3 /* TCP tracking. */ 4 5 /* This is exposed to userspace (ctnetlink) */ 6 enum tcp_conntrack { 7 TCP_CONNTRACK_NONE, 8 TCP_CONNTRACK_SYN_SENT, 9 TCP_CONNTRACK_SYN_RECV, 10 TCP_CONNTRACK_ESTABLISHED, 11 TCP_CONNTRACK_FIN_WAIT, 12 TCP_CONNTRACK_CLOSE_WAIT, 13 TCP_CONNTRACK_LAST_ACK, 14 TCP_CONNTRACK_TIME_WAIT, 15 TCP_CONNTRACK_CLOSE, 16 TCP_CONNTRACK_LISTEN, 17 TCP_CONNTRACK_MAX, 18 TCP_CONNTRACK_IGNORE 19 }; 20 21 /* Window scaling is advertised by the sender */ 22 #define IP_CT_TCP_FLAG_WINDOW_SCALE 0x01 23 24 /* SACK is permitted by the sender */ 25 #define IP_CT_TCP_FLAG_SACK_PERM 0x02 26 27 /* This sender sent FIN first */ 28 #define IP_CT_TCP_FLAG_CLOSE_INIT 0x03 29 30 #ifdef __KERNEL__ 31 32 struct ip_ct_tcp_state { 33 u_int32_t td_end; /* max of seq + len */ 34 u_int32_t td_maxend; /* max of ack + max(win, 1) */ 35 u_int32_t td_maxwin; /* max(win) */ 36 u_int8_t td_scale; /* window scale factor */ 37 u_int8_t loose; /* used when connection picked up from the middle */ 38 u_int8_t flags; /* per direction options */ 39 }; 40 41 struct ip_ct_tcp 42 { 43 struct ip_ct_tcp_state seen[2]; /* connection parameters per direction */ 44 u_int8_t state; /* state of the connection (enum tcp_conntrack) */ 45 /* For detecting stale connections */ 46 u_int8_t last_dir; /* Direction of the last packet (enum ip_conntrack_dir) */ 47 u_int8_t retrans; /* Number of retransmitted packets */ 48 u_int8_t last_index; /* Index of the last packet */ 49 u_int32_t last_seq; /* Last sequence number seen in dir */ 50 u_int32_t last_ack; /* Last sequence number seen in opposite dir */ 51 u_int32_t last_end; /* Last seq + len */ 52 }; 53 54 #endif /* __KERNEL__ */ 55 56 #endif /* _NF_CONNTRACK_TCP_H */ 57