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 23 struct 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 59 enum { 60 TCP_ESTABLISHED = 1, 61 TCP_SYN_SENT, 62 TCP_SYN_RECV, 63 TCP_FIN_WAIT1, 64 TCP_FIN_WAIT2, 65 TCP_TIME_WAIT, 66 TCP_CLOSE, 67 TCP_CLOSE_WAIT, 68 TCP_LAST_ACK, 69 TCP_LISTEN, 70 TCP_CLOSING, /* now a valid state */ 71 72 TCP_MAX_STATES /* Leave at the end! */ 73 }; 74 75 #define TCP_STATE_MASK 0xF 76 #define TCP_ACTION_FIN (1 << 7) 77 78 enum { 79 TCPF_ESTABLISHED = (1 << 1), 80 TCPF_SYN_SENT = (1 << 2), 81 TCPF_SYN_RECV = (1 << 3), 82 TCPF_FIN_WAIT1 = (1 << 4), 83 TCPF_FIN_WAIT2 = (1 << 5), 84 TCPF_TIME_WAIT = (1 << 6), 85 TCPF_CLOSE = (1 << 7), 86 TCPF_CLOSE_WAIT = (1 << 8), 87 TCPF_LAST_ACK = (1 << 9), 88 TCPF_LISTEN = (1 << 10), 89 TCPF_CLOSING = (1 << 11) 90 }; 91 92 /* 93 * The union cast uses a gcc extension to avoid aliasing problems 94 * (union is compatible to any of its members) 95 * This means this part of the code is -fstrict-aliasing safe now. 96 */ 97 union tcp_word_hdr { 98 struct tcphdr hdr; 99 __u32 words[5]; 100 }; 101 102 #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3]) 103 104 enum { 105 TCP_FLAG_CWR = __constant_htonl(0x00800000), 106 TCP_FLAG_ECE = __constant_htonl(0x00400000), 107 TCP_FLAG_URG = __constant_htonl(0x00200000), 108 TCP_FLAG_ACK = __constant_htonl(0x00100000), 109 TCP_FLAG_PSH = __constant_htonl(0x00080000), 110 TCP_FLAG_RST = __constant_htonl(0x00040000), 111 TCP_FLAG_SYN = __constant_htonl(0x00020000), 112 TCP_FLAG_FIN = __constant_htonl(0x00010000), 113 TCP_RESERVED_BITS = __constant_htonl(0x0F000000), 114 TCP_DATA_OFFSET = __constant_htonl(0xF0000000) 115 }; 116 117 /* TCP socket options */ 118 #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ 119 #define TCP_MAXSEG 2 /* Limit MSS */ 120 #define TCP_CORK 3 /* Never send partially complete segments */ 121 #define TCP_KEEPIDLE 4 /* Start keeplives after this period */ 122 #define TCP_KEEPINTVL 5 /* Interval between keepalives */ 123 #define TCP_KEEPCNT 6 /* Number of keepalives before death */ 124 #define TCP_SYNCNT 7 /* Number of SYN retransmits */ 125 #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */ 126 #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */ 127 #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */ 128 #define TCP_INFO 11 /* Information about this connection. */ 129 #define TCP_QUICKACK 12 /* Block/reenable quick acks */ 130 131 #define TCPI_OPT_TIMESTAMPS 1 132 #define TCPI_OPT_SACK 2 133 #define TCPI_OPT_WSCALE 4 134 #define TCPI_OPT_ECN 8 135 136 enum tcp_ca_state 137 { 138 TCP_CA_Open = 0, 139 #define TCPF_CA_Open (1<<TCP_CA_Open) 140 TCP_CA_Disorder = 1, 141 #define TCPF_CA_Disorder (1<<TCP_CA_Disorder) 142 TCP_CA_CWR = 2, 143 #define TCPF_CA_CWR (1<<TCP_CA_CWR) 144 TCP_CA_Recovery = 3, 145 #define TCPF_CA_Recovery (1<<TCP_CA_Recovery) 146 TCP_CA_Loss = 4 147 #define TCPF_CA_Loss (1<<TCP_CA_Loss) 148 }; 149 150 struct tcp_info 151 { 152 __u8 tcpi_state; 153 __u8 tcpi_ca_state; 154 __u8 tcpi_retransmits; 155 __u8 tcpi_probes; 156 __u8 tcpi_backoff; 157 __u8 tcpi_options; 158 __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4; 159 160 __u32 tcpi_rto; 161 __u32 tcpi_ato; 162 __u32 tcpi_snd_mss; 163 __u32 tcpi_rcv_mss; 164 165 __u32 tcpi_unacked; 166 __u32 tcpi_sacked; 167 __u32 tcpi_lost; 168 __u32 tcpi_retrans; 169 __u32 tcpi_fackets; 170 171 /* Times. */ 172 __u32 tcpi_last_data_sent; 173 __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */ 174 __u32 tcpi_last_data_recv; 175 __u32 tcpi_last_ack_recv; 176 177 /* Metrics. */ 178 __u32 tcpi_pmtu; 179 __u32 tcpi_rcv_ssthresh; 180 __u32 tcpi_rtt; 181 __u32 tcpi_rttvar; 182 __u32 tcpi_snd_ssthresh; 183 __u32 tcpi_snd_cwnd; 184 __u32 tcpi_advmss; 185 __u32 tcpi_reordering; 186 }; 187 188 #endif /* _LINUX_TCP_H */ 189