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, <[email protected]> 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 _UAPI_LINUX_TCP_H 18 #define _UAPI_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_cpu_to_be32(0x00800000), 73 TCP_FLAG_ECE = __constant_cpu_to_be32(0x00400000), 74 TCP_FLAG_URG = __constant_cpu_to_be32(0x00200000), 75 TCP_FLAG_ACK = __constant_cpu_to_be32(0x00100000), 76 TCP_FLAG_PSH = __constant_cpu_to_be32(0x00080000), 77 TCP_FLAG_RST = __constant_cpu_to_be32(0x00040000), 78 TCP_FLAG_SYN = __constant_cpu_to_be32(0x00020000), 79 TCP_FLAG_FIN = __constant_cpu_to_be32(0x00010000), 80 TCP_RESERVED_BITS = __constant_cpu_to_be32(0x0F000000), 81 TCP_DATA_OFFSET = __constant_cpu_to_be32(0xF0000000) 82 }; 83 84 /* 85 * TCP general constants 86 */ 87 #define TCP_MSS_DEFAULT 536U /* IPv4 (RFC1122, RFC2581) */ 88 #define TCP_MSS_DESIRED 1220U /* IPv6 (tunneled), EDNS0 (RFC3226) */ 89 90 /* TCP socket options */ 91 #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ 92 #define TCP_MAXSEG 2 /* Limit MSS */ 93 #define TCP_CORK 3 /* Never send partially complete segments */ 94 #define TCP_KEEPIDLE 4 /* Start keeplives after this period */ 95 #define TCP_KEEPINTVL 5 /* Interval between keepalives */ 96 #define TCP_KEEPCNT 6 /* Number of keepalives before death */ 97 #define TCP_SYNCNT 7 /* Number of SYN retransmits */ 98 #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */ 99 #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */ 100 #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */ 101 #define TCP_INFO 11 /* Information about this connection. */ 102 #define TCP_QUICKACK 12 /* Block/reenable quick acks */ 103 #define TCP_CONGESTION 13 /* Congestion control algorithm */ 104 #define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */ 105 #define TCP_THIN_LINEAR_TIMEOUTS 16 /* Use linear timeouts for thin streams*/ 106 #define TCP_THIN_DUPACK 17 /* Fast retrans. after 1 dupack */ 107 #define TCP_USER_TIMEOUT 18 /* How long for loss retry before timeout */ 108 #define TCP_REPAIR 19 /* TCP sock is under repair right now */ 109 #define TCP_REPAIR_QUEUE 20 110 #define TCP_QUEUE_SEQ 21 111 #define TCP_REPAIR_OPTIONS 22 112 #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */ 113 #define TCP_TIMESTAMP 24 114 #define TCP_NOTSENT_LOWAT 25 /* limit number of unsent bytes in write queue */ 115 #define TCP_CC_INFO 26 /* Get Congestion Control (optional) info */ 116 #define TCP_SAVE_SYN 27 /* Record SYN headers for new connections */ 117 #define TCP_SAVED_SYN 28 /* Get SYN headers recorded for connection */ 118 #define TCP_REPAIR_WINDOW 29 /* Get/set window parameters */ 119 #define TCP_FASTOPEN_CONNECT 30 /* Attempt FastOpen with connect */ 120 #define TCP_ULP 31 /* Attach a ULP to a TCP connection */ 121 #define TCP_MD5SIG_EXT 32 /* TCP MD5 Signature with extensions */ 122 123 struct tcp_repair_opt { 124 __u32 opt_code; 125 __u32 opt_val; 126 }; 127 128 struct tcp_repair_window { 129 __u32 snd_wl1; 130 __u32 snd_wnd; 131 __u32 max_window; 132 133 __u32 rcv_wnd; 134 __u32 rcv_wup; 135 }; 136 137 enum { 138 TCP_NO_QUEUE, 139 TCP_RECV_QUEUE, 140 TCP_SEND_QUEUE, 141 TCP_QUEUES_NR, 142 }; 143 144 /* for TCP_INFO socket option */ 145 #define TCPI_OPT_TIMESTAMPS 1 146 #define TCPI_OPT_SACK 2 147 #define TCPI_OPT_WSCALE 4 148 #define TCPI_OPT_ECN 8 /* ECN was negociated at TCP session init */ 149 #define TCPI_OPT_ECN_SEEN 16 /* we received at least one packet with ECT */ 150 #define TCPI_OPT_SYN_DATA 32 /* SYN-ACK acked data in SYN sent or rcvd */ 151 152 enum tcp_ca_state { 153 TCP_CA_Open = 0, 154 #define TCPF_CA_Open (1<<TCP_CA_Open) 155 TCP_CA_Disorder = 1, 156 #define TCPF_CA_Disorder (1<<TCP_CA_Disorder) 157 TCP_CA_CWR = 2, 158 #define TCPF_CA_CWR (1<<TCP_CA_CWR) 159 TCP_CA_Recovery = 3, 160 #define TCPF_CA_Recovery (1<<TCP_CA_Recovery) 161 TCP_CA_Loss = 4 162 #define TCPF_CA_Loss (1<<TCP_CA_Loss) 163 }; 164 165 struct tcp_info { 166 __u8 tcpi_state; 167 __u8 tcpi_ca_state; 168 __u8 tcpi_retransmits; 169 __u8 tcpi_probes; 170 __u8 tcpi_backoff; 171 __u8 tcpi_options; 172 __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4; 173 __u8 tcpi_delivery_rate_app_limited:1; 174 175 __u32 tcpi_rto; 176 __u32 tcpi_ato; 177 __u32 tcpi_snd_mss; 178 __u32 tcpi_rcv_mss; 179 180 __u32 tcpi_unacked; 181 __u32 tcpi_sacked; 182 __u32 tcpi_lost; 183 __u32 tcpi_retrans; 184 __u32 tcpi_fackets; 185 186 /* Times. */ 187 __u32 tcpi_last_data_sent; 188 __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */ 189 __u32 tcpi_last_data_recv; 190 __u32 tcpi_last_ack_recv; 191 192 /* Metrics. */ 193 __u32 tcpi_pmtu; 194 __u32 tcpi_rcv_ssthresh; 195 __u32 tcpi_rtt; 196 __u32 tcpi_rttvar; 197 __u32 tcpi_snd_ssthresh; 198 __u32 tcpi_snd_cwnd; 199 __u32 tcpi_advmss; 200 __u32 tcpi_reordering; 201 202 __u32 tcpi_rcv_rtt; 203 __u32 tcpi_rcv_space; 204 205 __u32 tcpi_total_retrans; 206 207 __u64 tcpi_pacing_rate; 208 __u64 tcpi_max_pacing_rate; 209 __u64 tcpi_bytes_acked; /* RFC4898 tcpEStatsAppHCThruOctetsAcked */ 210 __u64 tcpi_bytes_received; /* RFC4898 tcpEStatsAppHCThruOctetsReceived */ 211 __u32 tcpi_segs_out; /* RFC4898 tcpEStatsPerfSegsOut */ 212 __u32 tcpi_segs_in; /* RFC4898 tcpEStatsPerfSegsIn */ 213 214 __u32 tcpi_notsent_bytes; 215 __u32 tcpi_min_rtt; 216 __u32 tcpi_data_segs_in; /* RFC4898 tcpEStatsDataSegsIn */ 217 __u32 tcpi_data_segs_out; /* RFC4898 tcpEStatsDataSegsOut */ 218 219 __u64 tcpi_delivery_rate; 220 221 __u64 tcpi_busy_time; /* Time (usec) busy sending data */ 222 __u64 tcpi_rwnd_limited; /* Time (usec) limited by receive window */ 223 __u64 tcpi_sndbuf_limited; /* Time (usec) limited by send buffer */ 224 }; 225 226 /* netlink attributes types for SCM_TIMESTAMPING_OPT_STATS */ 227 enum { 228 TCP_NLA_PAD, 229 TCP_NLA_BUSY, /* Time (usec) busy sending data */ 230 TCP_NLA_RWND_LIMITED, /* Time (usec) limited by receive window */ 231 TCP_NLA_SNDBUF_LIMITED, /* Time (usec) limited by send buffer */ 232 TCP_NLA_DATA_SEGS_OUT, /* Data pkts sent including retransmission */ 233 TCP_NLA_TOTAL_RETRANS, /* Data pkts retransmitted */ 234 TCP_NLA_PACING_RATE, /* Pacing rate in bytes per second */ 235 TCP_NLA_DELIVERY_RATE, /* Delivery rate in bytes per second */ 236 TCP_NLA_SND_CWND, /* Sending congestion window */ 237 TCP_NLA_REORDERING, /* Reordering metric */ 238 TCP_NLA_MIN_RTT, /* minimum RTT */ 239 TCP_NLA_RECUR_RETRANS, /* Recurring retransmits for the current pkt */ 240 TCP_NLA_DELIVERY_RATE_APP_LMT, /* delivery rate application limited ? */ 241 242 }; 243 244 /* for TCP_MD5SIG socket option */ 245 #define TCP_MD5SIG_MAXKEYLEN 80 246 247 /* tcp_md5sig extension flags for TCP_MD5SIG_EXT */ 248 #define TCP_MD5SIG_FLAG_PREFIX 1 /* address prefix length */ 249 250 struct tcp_md5sig { 251 struct __kernel_sockaddr_storage tcpm_addr; /* address associated */ 252 __u8 tcpm_flags; /* extension flags */ 253 __u8 tcpm_prefixlen; /* address prefix */ 254 __u16 tcpm_keylen; /* key length */ 255 __u32 __tcpm_pad; /* zero */ 256 __u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */ 257 }; 258 259 #endif /* _UAPI_LINUX_TCP_H */ 260