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 #include <linux/socket.h> 23 24 struct tcphdr { 25 __be16 source; 26 __be16 dest; 27 __be32 seq; 28 __be32 ack_seq; 29 #if defined(__LITTLE_ENDIAN_BITFIELD) 30 __u16 res1:4, 31 doff:4, 32 fin:1, 33 syn:1, 34 rst:1, 35 psh:1, 36 ack:1, 37 urg:1, 38 ece:1, 39 cwr:1; 40 #elif defined(__BIG_ENDIAN_BITFIELD) 41 __u16 doff:4, 42 res1:4, 43 cwr:1, 44 ece:1, 45 urg:1, 46 ack:1, 47 psh:1, 48 rst:1, 49 syn:1, 50 fin:1; 51 #else 52 #error "Adjust your <asm/byteorder.h> defines" 53 #endif 54 __be16 window; 55 __sum16 check; 56 __be16 urg_ptr; 57 }; 58 59 /* 60 * The union cast uses a gcc extension to avoid aliasing problems 61 * (union is compatible to any of its members) 62 * This means this part of the code is -fstrict-aliasing safe now. 63 */ 64 union tcp_word_hdr { 65 struct tcphdr hdr; 66 __be32 words[5]; 67 }; 68 69 #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3]) 70 71 enum { 72 TCP_FLAG_CWR = __constant_htonl(0x00800000), 73 TCP_FLAG_ECE = __constant_htonl(0x00400000), 74 TCP_FLAG_URG = __constant_htonl(0x00200000), 75 TCP_FLAG_ACK = __constant_htonl(0x00100000), 76 TCP_FLAG_PSH = __constant_htonl(0x00080000), 77 TCP_FLAG_RST = __constant_htonl(0x00040000), 78 TCP_FLAG_SYN = __constant_htonl(0x00020000), 79 TCP_FLAG_FIN = __constant_htonl(0x00010000), 80 TCP_RESERVED_BITS = __constant_htonl(0x0F000000), 81 TCP_DATA_OFFSET = __constant_htonl(0xF0000000) 82 }; 83 84 /* TCP socket options */ 85 #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ 86 #define TCP_MAXSEG 2 /* Limit MSS */ 87 #define TCP_CORK 3 /* Never send partially complete segments */ 88 #define TCP_KEEPIDLE 4 /* Start keeplives after this period */ 89 #define TCP_KEEPINTVL 5 /* Interval between keepalives */ 90 #define TCP_KEEPCNT 6 /* Number of keepalives before death */ 91 #define TCP_SYNCNT 7 /* Number of SYN retransmits */ 92 #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */ 93 #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */ 94 #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */ 95 #define TCP_INFO 11 /* Information about this connection. */ 96 #define TCP_QUICKACK 12 /* Block/reenable quick acks */ 97 #define TCP_CONGESTION 13 /* Congestion control algorithm */ 98 #define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */ 99 100 #define TCPI_OPT_TIMESTAMPS 1 101 #define TCPI_OPT_SACK 2 102 #define TCPI_OPT_WSCALE 4 103 #define TCPI_OPT_ECN 8 104 105 enum tcp_ca_state 106 { 107 TCP_CA_Open = 0, 108 #define TCPF_CA_Open (1<<TCP_CA_Open) 109 TCP_CA_Disorder = 1, 110 #define TCPF_CA_Disorder (1<<TCP_CA_Disorder) 111 TCP_CA_CWR = 2, 112 #define TCPF_CA_CWR (1<<TCP_CA_CWR) 113 TCP_CA_Recovery = 3, 114 #define TCPF_CA_Recovery (1<<TCP_CA_Recovery) 115 TCP_CA_Loss = 4 116 #define TCPF_CA_Loss (1<<TCP_CA_Loss) 117 }; 118 119 struct tcp_info 120 { 121 __u8 tcpi_state; 122 __u8 tcpi_ca_state; 123 __u8 tcpi_retransmits; 124 __u8 tcpi_probes; 125 __u8 tcpi_backoff; 126 __u8 tcpi_options; 127 __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4; 128 129 __u32 tcpi_rto; 130 __u32 tcpi_ato; 131 __u32 tcpi_snd_mss; 132 __u32 tcpi_rcv_mss; 133 134 __u32 tcpi_unacked; 135 __u32 tcpi_sacked; 136 __u32 tcpi_lost; 137 __u32 tcpi_retrans; 138 __u32 tcpi_fackets; 139 140 /* Times. */ 141 __u32 tcpi_last_data_sent; 142 __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */ 143 __u32 tcpi_last_data_recv; 144 __u32 tcpi_last_ack_recv; 145 146 /* Metrics. */ 147 __u32 tcpi_pmtu; 148 __u32 tcpi_rcv_ssthresh; 149 __u32 tcpi_rtt; 150 __u32 tcpi_rttvar; 151 __u32 tcpi_snd_ssthresh; 152 __u32 tcpi_snd_cwnd; 153 __u32 tcpi_advmss; 154 __u32 tcpi_reordering; 155 156 __u32 tcpi_rcv_rtt; 157 __u32 tcpi_rcv_space; 158 159 __u32 tcpi_total_retrans; 160 }; 161 162 /* for TCP_MD5SIG socket option */ 163 #define TCP_MD5SIG_MAXKEYLEN 80 164 165 struct tcp_md5sig { 166 struct __kernel_sockaddr_storage tcpm_addr; /* address associated */ 167 __u16 __tcpm_pad1; /* zero */ 168 __u16 tcpm_keylen; /* key length */ 169 __u32 __tcpm_pad2; /* zero */ 170 __u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */ 171 }; 172 173 174 #endif /* _LINUX_TCP_H */ 175