tcp.h revision 1.32
1 /* $NetBSD: tcp.h,v 1.32 2017/01/02 01:18:42 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)tcp.h 8.1 (Berkeley) 6/10/93 32 */ 33 34 #ifndef _NETINET_TCP_H_ 35 #define _NETINET_TCP_H_ 36 37 #include <sys/featuretest.h> 38 39 #if defined(_NETBSD_SOURCE) 40 #include <sys/types.h> 41 42 typedef uint32_t tcp_seq; 43 /* 44 * TCP header. 45 * Per RFC 793, September, 1981. 46 * Updated by RFC 3168, September, 2001. 47 */ 48 struct tcphdr { 49 uint16_t th_sport; /* source port */ 50 uint16_t th_dport; /* destination port */ 51 tcp_seq th_seq; /* sequence number */ 52 tcp_seq th_ack; /* acknowledgement number */ 53 #if BYTE_ORDER == LITTLE_ENDIAN 54 /*LINTED non-portable bitfields*/ 55 uint8_t th_x2:4, /* (unused) */ 56 th_off:4; /* data offset */ 57 #endif 58 #if BYTE_ORDER == BIG_ENDIAN 59 /*LINTED non-portable bitfields*/ 60 uint8_t th_off:4, /* data offset */ 61 th_x2:4; /* (unused) */ 62 #endif 63 uint8_t th_flags; 64 #define TH_FIN 0x01 65 #define TH_SYN 0x02 66 #define TH_RST 0x04 67 #define TH_PUSH 0x08 68 #define TH_ACK 0x10 69 #define TH_URG 0x20 70 #define TH_ECE 0x40 71 #define TH_CWR 0x80 72 uint16_t th_win; /* window */ 73 uint16_t th_sum; /* checksum */ 74 uint16_t th_urp; /* urgent pointer */ 75 } __packed; 76 77 #define TCPOPT_EOL 0 78 #define TCPOLEN_EOL 1 79 #define TCPOPT_PAD 0 80 #define TCPOLEN_PAD 1 81 #define TCPOPT_NOP 1 82 #define TCPOLEN_NOP 1 83 #define TCPOPT_MAXSEG 2 84 #define TCPOLEN_MAXSEG 4 85 #define TCPOPT_WINDOW 3 86 #define TCPOLEN_WINDOW 3 87 #define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 88 #define TCPOLEN_SACK_PERMITTED 2 89 #define TCPOPT_SACK 5 /* Experimental */ 90 #define TCPOPT_TIMESTAMP 8 91 #define TCPOLEN_TIMESTAMP 10 92 #define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 93 94 #define TCPOPT_TSTAMP_HDR \ 95 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 96 97 #define TCPOPT_SIGNATURE 19 /* Keyed MD5: RFC 2385 */ 98 #define TCPOLEN_SIGNATURE 18 99 #define TCPOLEN_SIGLEN (TCPOLEN_SIGNATURE+2) /* padding */ 100 101 #define MAX_TCPOPTLEN 40 /* max # bytes that go in options */ 102 103 /* 104 * Default maximum segment size for TCP. 105 * This is defined by RFC 1112 Sec 4.2.2.6. 106 */ 107 #define TCP_MSS 536 108 109 #define TCP_MINMSS 216 110 111 #define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 112 113 #define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 114 115 #define TCP_MAXBURST 4 /* maximum segments in a burst */ 116 117 #endif /* _NETBSD_SOURCE */ 118 119 /* 120 * User-settable options (used with setsockopt). 121 */ 122 #define TCP_NODELAY 1 /* don't delay send to coalesce packets */ 123 #define TCP_MAXSEG 2 /* set maximum segment size */ 124 #define TCP_KEEPIDLE 3 125 #ifdef notyet 126 #define TCP_NOPUSH 4 /* reserved for FreeBSD compat */ 127 #endif 128 #define TCP_KEEPINTVL 5 129 #define TCP_KEEPCNT 6 130 #define TCP_KEEPINIT 7 131 #ifdef notyet 132 #define TCP_NOOPT 8 /* reserved for FreeBSD compat */ 133 #endif 134 #define TCP_INFO 9 /* retrieve tcp_info structure */ 135 #define TCP_MD5SIG 0x10 /* use MD5 digests (RFC2385) */ 136 #define TCP_CONGCTL 0x20 /* selected congestion control */ 137 138 #define TCPI_OPT_TIMESTAMPS 0x01 139 #define TCPI_OPT_SACK 0x02 140 #define TCPI_OPT_WSCALE 0x04 141 #define TCPI_OPT_ECN 0x08 142 #define TCPI_OPT_TOE 0x10 143 144 /* 145 * The TCP_INFO socket option comes from the Linux 2.6 TCP API, and permits 146 * the caller to query certain information about the state of a TCP 147 * connection. We provide an overlapping set of fields with the Linux 148 * implementation, but since this is a fixed size structure, room has been 149 * left for growth. In order to maximize potential future compatibility with 150 * the Linux API, the same variable names and order have been adopted, and 151 * padding left to make room for omitted fields in case they are added later. 152 * 153 * XXX: This is currently an unstable ABI/API, in that it is expected to 154 * change. 155 */ 156 struct tcp_info { 157 uint8_t tcpi_state; /* TCP FSM state. */ 158 uint8_t __tcpi_ca_state; 159 uint8_t __tcpi_retransmits; 160 uint8_t __tcpi_probes; 161 uint8_t __tcpi_backoff; 162 uint8_t tcpi_options; /* Options enabled on conn. */ 163 uint8_t tcpi_snd_wscale:4, /* RFC1323 send shift value. */ 164 tcpi_rcv_wscale:4; /* RFC1323 recv shift value. */ 165 166 uint32_t tcpi_rto; /* Retransmission timeout (usec). */ 167 uint32_t __tcpi_ato; 168 uint32_t tcpi_snd_mss; /* Max segment size for send. */ 169 uint32_t tcpi_rcv_mss; /* Max segment size for receive. */ 170 171 uint32_t __tcpi_unacked; 172 uint32_t __tcpi_sacked; 173 uint32_t __tcpi_lost; 174 uint32_t __tcpi_retrans; 175 uint32_t __tcpi_fackets; 176 177 /* Times; measurements in usecs. */ 178 uint32_t __tcpi_last_data_sent; 179 uint32_t __tcpi_last_ack_sent; /* Also unimpl. on Linux? */ 180 uint32_t tcpi_last_data_recv; /* Time since last recv data. */ 181 uint32_t __tcpi_last_ack_recv; 182 183 /* Metrics; variable units. */ 184 uint32_t __tcpi_pmtu; 185 uint32_t __tcpi_rcv_ssthresh; 186 uint32_t tcpi_rtt; /* Smoothed RTT in usecs. */ 187 uint32_t tcpi_rttvar; /* RTT variance in usecs. */ 188 uint32_t tcpi_snd_ssthresh; /* Slow start threshold. */ 189 uint32_t tcpi_snd_cwnd; /* Send congestion window. */ 190 uint32_t __tcpi_advmss; 191 uint32_t __tcpi_reordering; 192 193 uint32_t __tcpi_rcv_rtt; 194 uint32_t tcpi_rcv_space; /* Advertised recv window. */ 195 196 /* FreeBSD/NetBSD extensions to tcp_info. */ 197 uint32_t tcpi_snd_wnd; /* Advertised send window. */ 198 uint32_t tcpi_snd_bwnd; /* No longer used. */ 199 uint32_t tcpi_snd_nxt; /* Next egress seqno */ 200 uint32_t tcpi_rcv_nxt; /* Next ingress seqno */ 201 uint32_t tcpi_toe_tid; /* HWTID for TOE endpoints */ 202 uint32_t tcpi_snd_rexmitpack; /* Retransmitted packets */ 203 uint32_t tcpi_rcv_ooopack; /* Out-of-order packets */ 204 uint32_t tcpi_snd_zerowin; /* Zero-sized windows sent */ 205 206 /* Padding to grow without breaking ABI. */ 207 uint32_t __tcpi_pad[26]; /* Padding. */ 208 }; 209 210 #endif /* !_NETINET_TCP_H_ */ 211
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