1 /* $NetBSD: tcp.h,v 1.15 2003/08/07 16:33:15 agc 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 41 typedef u_int32_t tcp_seq; 42 /* 43 * TCP header. 44 * Per RFC 793, September, 1981. 45 */ 46 struct tcphdr { 47 u_int16_t th_sport; /* source port */ 48 u_int16_t th_dport; /* destination port */ 49 tcp_seq th_seq; /* sequence number */ 50 tcp_seq th_ack; /* acknowledgement number */ 51 #if BYTE_ORDER == LITTLE_ENDIAN 52 /*LINTED non-portable bitfields*/ 53 u_int8_t th_x2:4, /* (unused) */ 54 th_off:4; /* data offset */ 55 #endif 56 #if BYTE_ORDER == BIG_ENDIAN 57 /*LINTED non-portable bitfields*/ 58 u_int8_t th_off:4, /* data offset */ 59 th_x2:4; /* (unused) */ 60 #endif 61 u_int8_t th_flags; 62 #define TH_FIN 0x01 63 #define TH_SYN 0x02 64 #define TH_RST 0x04 65 #define TH_PUSH 0x08 66 #define TH_ACK 0x10 67 #define TH_URG 0x20 68 u_int16_t th_win; /* window */ 69 u_int16_t th_sum; /* checksum */ 70 u_int16_t th_urp; /* urgent pointer */ 71 } __attribute__((__packed__)); 72 73 #define TCPOPT_EOL 0 74 #define TCPOPT_NOP 1 75 #define TCPOPT_MAXSEG 2 76 #define TCPOLEN_MAXSEG 4 77 #define TCPOPT_WINDOW 3 78 #define TCPOLEN_WINDOW 3 79 #define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 80 #define TCPOLEN_SACK_PERMITTED 2 81 #define TCPOPT_SACK 5 /* Experimental */ 82 #define TCPOPT_TIMESTAMP 8 83 #define TCPOLEN_TIMESTAMP 10 84 #define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 85 #define TCPOPT_MD5SIGNATURE 19 /* RFC 2385 */ 86 #define TCPOLEN_MD5SIGNATURE 18 87 88 #define TCPOPT_TSTAMP_HDR \ 89 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 90 91 /* 92 * Default maximum segment size for TCP. 93 * With an IP MSS of 576, this is 536, 94 * but 512 is probably more convenient. 95 * This should be defined as min(512, IP_MSS - sizeof (struct tcpiphdr)). 96 */ 97 #define TCP_MSS 512 98 99 #define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 100 101 #define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 102 103 #define TCP_MAXBURST 4 /* maximum segments in a burst */ 104 105 #endif /* _NETBSD_SOURCE */ 106 107 /* 108 * User-settable options (used with setsockopt). 109 */ 110 #define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 111 #define TCP_MAXSEG 0x02 /* set maximum segment size */ 112 113 #endif /* _NETINET_TCP_H_ */ 114