1/* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Definitions for the TCP protocol. 7 * 8 * Version: @(#)tcp.h 1.0.2 04/28/93 9 * 10 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * as published by the Free Software Foundation; either version 15 * 2 of the License, or (at your option) any later version. 16 */ 17#ifndef _LINUX_TCP_H 18#define _LINUX_TCP_H 19 20#include <linux/types.h> 21#include <asm/byteorder.h> 22 23struct tcphdr { 24 __u16 source; 25 __u16 dest; 26 __u32 seq; 27 __u32 ack_seq; 28#if defined(__LITTLE_ENDIAN_BITFIELD) 29 __u16 res1:4, 30 doff:4, 31 fin:1, 32 syn:1, 33 rst:1, 34 psh:1, 35 ack:1, 36 urg:1, 37 ece:1, 38 cwr:1; 39#elif defined(__BIG_ENDIAN_BITFIELD) 40 __u16 doff:4, 41 res1:4, 42 cwr:1, 43 ece:1, 44 urg:1, 45 ack:1, 46 psh:1, 47 rst:1, 48 syn:1, 49 fin:1; 50#else 51#error "Adjust your <asm/byteorder.h> defines" 52#endif 53 __u16 window; 54 __u16 check; 55 __u16 urg_ptr; 56}; 57 58#define TCP_ACTION_FIN (1 << 7) 59 60enum { 61 TCPF_ESTABLISHED = (1 << 1), 62 TCPF_SYN_SENT = (1 << 2), 63 TCPF_SYN_RECV = (1 << 3), 64 TCPF_FIN_WAIT1 = (1 << 4), 65 TCPF_FIN_WAIT2 = (1 << 5), 66 TCPF_TIME_WAIT = (1 << 6), 67 TCPF_CLOSE = (1 << 7), 68 TCPF_CLOSE_WAIT = (1 << 8), 69 TCPF_LAST_ACK = (1 << 9), 70 TCPF_LISTEN = (1 << 10), 71 TCPF_CLOSING = (1 << 11) 72}; 73 74/* 75 * The union cast uses a gcc extension to avoid aliasing problems 76 * (union is compatible to any of its members) 77 * This means this part of the code is -fstrict-aliasing safe now. 78 */ 79union tcp_word_hdr { 80 struct tcphdr hdr; 81 __u32 words[5]; 82}; 83 84#define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3]) 85 86enum { 87 TCP_FLAG_CWR = __constant_htonl(0x00800000), 88 TCP_FLAG_ECE = __constant_htonl(0x00400000), 89 TCP_FLAG_URG = __constant_htonl(0x00200000), 90 TCP_FLAG_ACK = __constant_htonl(0x00100000), 91 TCP_FLAG_PSH = __constant_htonl(0x00080000), 92 TCP_FLAG_RST = __constant_htonl(0x00040000), 93 TCP_FLAG_SYN = __constant_htonl(0x00020000), 94 TCP_FLAG_FIN = __constant_htonl(0x00010000), 95 TCP_RESERVED_BITS = __constant_htonl(0x0F000000), 96 TCP_DATA_OFFSET = __constant_htonl(0xF0000000) 97}; 98 99/* TCP socket options */ 100#define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ 101#define TCP_MAXSEG 2 /* Limit MSS */ 102#define TCP_CORK 3 /* Never send partially complete segments */ 103#define TCP_KEEPIDLE 4 /* Start keeplives after this period */ 104#define TCP_KEEPINTVL 5 /* Interval between keepalives */ 105#define TCP_KEEPCNT 6 /* Number of keepalives before death */ 106#define TCP_SYNCNT 7 /* Number of SYN retransmits */ 107#define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */ 108#define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */ 109#define TCP_WINDOW_CLAMP 10 /* Bound advertised window */ 110#define TCP_INFO 11 /* Information about this connection. */ 111#define TCP_QUICKACK 12 /* Block/reenable quick acks */ 112#define TCP_CONGESTION 13 /* Congestion control algorithm */ 113 114#define TCPI_OPT_TIMESTAMPS 1 115#define TCPI_OPT_SACK 2 116#define TCPI_OPT_WSCALE 4 117#define TCPI_OPT_ECN 8 118 119enum tcp_ca_state 120{ 121 TCP_CA_Open = 0, 122#define TCPF_CA_Open (1<<TCP_CA_Open) 123 TCP_CA_Disorder = 1, 124#define TCPF_CA_Disorder (1<<TCP_CA_Disorder) 125 TCP_CA_CWR = 2, 126#define TCPF_CA_CWR (1<<TCP_CA_CWR) 127 TCP_CA_Recovery = 3, 128#define TCPF_CA_Recovery (1<<TCP_CA_Recovery) 129 TCP_CA_Loss = 4 130#define TCPF_CA_Loss (1<<TCP_CA_Loss) 131}; 132 133struct tcp_info 134{ 135 __u8 tcpi_state; 136 __u8 tcpi_ca_state; 137 __u8 tcpi_retransmits; 138 __u8 tcpi_probes; 139 __u8 tcpi_backoff; 140 __u8 tcpi_options; 141 __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4; 142 143 __u32 tcpi_rto; 144 __u32 tcpi_ato; 145 __u32 tcpi_snd_mss; 146 __u32 tcpi_rcv_mss; 147 148 __u32 tcpi_unacked; 149 __u32 tcpi_sacked; 150 __u32 tcpi_lost; 151 __u32 tcpi_retrans; 152 __u32 tcpi_fackets; 153 154 /* Times. */ 155 __u32 tcpi_last_data_sent; 156 __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */ 157 __u32 tcpi_last_data_recv; 158 __u32 tcpi_last_ack_recv; 159 160 /* Metrics. */ 161 __u32 tcpi_pmtu; 162 __u32 tcpi_rcv_ssthresh; 163 __u32 tcpi_rtt; 164 __u32 tcpi_rttvar; 165 __u32 tcpi_snd_ssthresh; 166 __u32 tcpi_snd_cwnd; 167 __u32 tcpi_advmss; 168 __u32 tcpi_reordering; 169 170 __u32 tcpi_rcv_rtt; 171 __u32 tcpi_rcv_space; 172 173 __u32 tcpi_total_retrans; 174}; 175 176 177#endif /* _LINUX_TCP_H */ 178