1 /* 2 * Copyright (c) 1982, 1986, 1993 3 * The Regents of the University of California. 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 8.1 (Berkeley) 6/10/93 34 * $FreeBSD$ 35 */ 36 37 #ifndef _NETINET_TCP_H_ 38 #define _NETINET_TCP_H_ 39 40 typedef u_int32_t tcp_seq; 41 typedef u_int32_t tcp_cc; /* connection count per rfc1644 */ 42 43 #define tcp6_seq tcp_seq /* for KAME src sync over BSD*'s */ 44 #define tcp6hdr tcphdr /* for KAME src sync over BSD*'s */ 45 46 /* 47 * TCP header. 48 * Per RFC 793, September, 1981. 49 */ 50 struct tcphdr { 51 u_short th_sport; /* source port */ 52 u_short th_dport; /* destination port */ 53 tcp_seq th_seq; /* sequence number */ 54 tcp_seq th_ack; /* acknowledgement number */ 55 #if BYTE_ORDER == LITTLE_ENDIAN 56 u_int th_x2:4, /* (unused) */ 57 th_off:4; /* data offset */ 58 #endif 59 #if BYTE_ORDER == BIG_ENDIAN 60 u_int th_off:4, /* data offset */ 61 th_x2:4; /* (unused) */ 62 #endif 63 u_char 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 #define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG|TH_ECE|TH_CWR) 73 74 u_short th_win; /* window */ 75 u_short th_sum; /* checksum */ 76 u_short th_urp; /* urgent pointer */ 77 }; 78 79 #define TCPOPT_EOL 0 80 #define TCPOPT_NOP 1 81 #define TCPOPT_MAXSEG 2 82 #define TCPOLEN_MAXSEG 4 83 #define TCPOPT_WINDOW 3 84 #define TCPOLEN_WINDOW 3 85 #define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 86 #define TCPOLEN_SACK_PERMITTED 2 87 #define TCPOPT_SACK 5 /* Experimental */ 88 #define TCPOPT_TIMESTAMP 8 89 #define TCPOLEN_TIMESTAMP 10 90 #define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 91 #define TCPOPT_TSTAMP_HDR \ 92 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 93 94 #define TCPOPT_CC 11 /* CC options: RFC-1644 */ 95 #define TCPOPT_CCNEW 12 96 #define TCPOPT_CCECHO 13 97 #define TCPOLEN_CC 6 98 #define TCPOLEN_CC_APPA (TCPOLEN_CC+2) 99 #define TCPOPT_CC_HDR(ccopt) \ 100 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|(ccopt)<<8|TCPOLEN_CC) 101 102 /* 103 * Default maximum segment size for TCP. 104 * With an IP MSS of 576, this is 536, 105 * but 512 is probably more convenient. 106 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)). 107 */ 108 #define TCP_MSS 512 109 110 /* 111 * Default maximum segment size for TCP6. 112 * With an IP6 MSS of 1280, this is 1220, 113 * but 1024 is probably more convenient. (xxx kazu in doubt) 114 * This should be defined as MIN(1024, IP6_MSS - sizeof (struct tcpip6hdr)) 115 */ 116 #define TCP6_MSS 1024 117 118 #define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 119 #define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */ 120 121 #define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 122 123 #define TCP_MAXBURST 4 /* maximum segments in a burst */ 124 125 #define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */ 126 #define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr)) 127 /* max space left for options */ 128 129 /* 130 * User-settable options (used with setsockopt). 131 */ 132 #define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 133 #define TCP_MAXSEG 0x02 /* set maximum segment size */ 134 #define TCP_NOPUSH 0x04 /* don't push last block of write */ 135 #define TCP_NOOPT 0x08 /* don't use TCP options */ 136 137 #endif 138