nf_conntrack_tcp.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _NF_CONNTRACK_TCP_H
#define _NF_CONNTRACK_TCP_H
#include <uapi/linux/netfilter/nf_conntrack_tcp.h>
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_int32_t td_maxack; /* max of ack */
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 */
/* For SYN packets while we may be out-of-sync */
u_int8_t last_wscale; /* Last window scaling factor seen */
u_int8_t last_flags; /* Last flags set */
};
#endif /* _NF_CONNTRACK_TCP_H */