1 /* 2 * Copyright (c) 1982, 1986 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)tcp.h 7.7 (Berkeley) 6/28/90 34 */ 35 36 #ifndef _NETINET_TCP_H_ 37 #define _NETINET_TCP_H_ 38 39 typedef u_long tcp_seq; 40 /* 41 * TCP header. 42 * Per RFC 793, September, 1981. 43 */ 44 struct tcphdr { 45 u_short th_sport; /* source port */ 46 u_short th_dport; /* destination port */ 47 tcp_seq th_seq; /* sequence number */ 48 tcp_seq th_ack; /* acknowledgement number */ 49 #if BYTE_ORDER == LITTLE_ENDIAN 50 u_char th_x2:4, /* (unused) */ 51 th_off:4; /* data offset */ 52 #endif 53 #if BYTE_ORDER == BIG_ENDIAN 54 u_char th_off:4, /* data offset */ 55 th_x2:4; /* (unused) */ 56 #endif 57 u_char th_flags; 58 #define TH_FIN 0x01 59 #define TH_SYN 0x02 60 #define TH_RST 0x04 61 #define TH_PUSH 0x08 62 #define TH_ACK 0x10 63 #define TH_URG 0x20 64 u_short th_win; /* window */ 65 u_short th_sum; /* checksum */ 66 u_short th_urp; /* urgent pointer */ 67 }; 68 69 #define TCPOPT_EOL 0 70 #define TCPOPT_NOP 1 71 #define TCPOPT_MAXSEG 2 72 73 /* 74 * Default maximum segment size for TCP. 75 * With an IP MSS of 576, this is 536, 76 * but 512 is probably more convenient. 77 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)). 78 */ 79 #define TCP_MSS 512 80 81 #define TCP_MAXWIN 65535 /* largest value for window */ 82 83 /* 84 * User-settable options (used with setsockopt). 85 */ 86 #define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 87 #define TCP_MAXSEG 0x02 /* set maximum segment size */ 88 89 #endif /* !_NETINET_TCP_H_ */ 90