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 * tcp.h,v 1.3 1994/08/21 05:27:34 paul Exp 35 */ 36 37#ifndef _TCP_H_ 38#define _TCP_H_ 39 40#include "helper.h" 41 42typedef u_int32_t tcp_seq; 43 44#define PR_SLOWHZ 2 /* 2 slow timeouts per second (approx) */ 45#define PR_FASTHZ 5 /* 5 fast timeouts per second (not important) */ 46 47extern struct socket *tcp_last_so; 48 49#define TCP_SNDSPACE 8192 50#define TCP_RCVSPACE 8192 51 52/* 53 * TCP header. 54 * Per RFC 793, September, 1981. 55 */ 56struct tcphdr { 57 port_t th_sport; /* source port */ 58 port_t th_dport; /* destination port */ 59 tcp_seq th_seq; /* sequence number */ 60 tcp_seq th_ack; /* acknowledgement number */ 61#ifdef HOST_WORDS_BIGENDIAN 62 u_int th_off:4, /* data offset */ 63 th_x2:4; /* (unused) */ 64#else 65 u_int th_x2:4, /* (unused) */ 66 th_off:4; /* data offset */ 67#endif 68 u_int8_t th_flags; 69#define TH_FIN 0x01 70#define TH_SYN 0x02 71#define TH_RST 0x04 72#define TH_PUSH 0x08 73#define TH_ACK 0x10 74#define TH_URG 0x20 75 u_int16_t th_win; /* window */ 76 u_int16_t th_sum; /* checksum */ 77 u_int16_t th_urp; /* urgent pointer */ 78}; 79 80#include "tcp_var.h" 81 82#define TCPOPT_EOL 0 83#define TCPOPT_NOP 1 84#define TCPOPT_MAXSEG 2 85#define TCPOLEN_MAXSEG 4 86#define TCPOPT_WINDOW 3 87#define TCPOLEN_WINDOW 3 88#define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 89#define TCPOLEN_SACK_PERMITTED 2 90#define TCPOPT_SACK 5 /* Experimental */ 91#define TCPOPT_TIMESTAMP 8 92#define TCPOLEN_TIMESTAMP 10 93#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 94 95#define TCPOPT_TSTAMP_HDR \ 96 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 97 98/* 99 * Default maximum segment size for TCP. 100 * With an IP MSS of 576, this is 536, 101 * but 512 is probably more convenient. 102 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)). 103 * 104 * We make this 1460 because we only care about Ethernet in the qemu context. 105 */ 106#define TCP_MSS 1460 107 108#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 109 110#define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 111 112/* 113 * User-settable options (used with setsockopt). 114 */ 115#undef TCP_NODELAY 116#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 117#undef TCP_MAXSEG 118/* #define TCP_MAXSEG 0x02 */ /* set maximum segment size */ 119 120/* 121 * TCP FSM state definitions. 122 * Per RFC793, September, 1981. 123 */ 124 125#define TCP_NSTATES 11 126 127#define TCPS_CLOSED 0 /* closed */ 128#define TCPS_LISTEN 1 /* listening for connection */ 129#define TCPS_SYN_SENT 2 /* active, have sent syn */ 130#define TCPS_SYN_RECEIVED 3 /* have send and received syn */ 131/* states < TCPS_ESTABLISHED are those where connections not established */ 132#define TCPS_ESTABLISHED 4 /* established */ 133#define TCPS_CLOSE_WAIT 5 /* rcvd fin, waiting for close */ 134/* states > TCPS_CLOSE_WAIT are those where user has closed */ 135#define TCPS_FIN_WAIT_1 6 /* have closed, sent fin */ 136#define TCPS_CLOSING 7 /* closed xchd FIN; await FIN ACK */ 137#define TCPS_LAST_ACK 8 /* had fin and close; await FIN ACK */ 138/* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */ 139#define TCPS_FIN_WAIT_2 9 /* have closed, fin is acked */ 140#define TCPS_TIME_WAIT 10 /* in 2*msl quiet wait after close */ 141 142#define TCPS_HAVERCVDSYN(s) ((s) >= TCPS_SYN_RECEIVED) 143#define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED) 144#define TCPS_HAVERCVDFIN(s) ((s) >= TCPS_TIME_WAIT) 145 146/* 147 * TCP sequence numbers are 32 bit integers operated 148 * on with modular arithmetic. These macros can be 149 * used to compare such integers. 150 */ 151#define SEQ_LT(a,b) ((int)((a)-(b)) < 0) 152#define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0) 153#define SEQ_GT(a,b) ((int)((a)-(b)) > 0) 154#define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0) 155 156/* 157 * Macros to initialize tcp sequence numbers for 158 * send and receive from initial send and receive 159 * sequence numbers. 160 */ 161#define tcp_rcvseqinit(tp) \ 162 (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1 163 164#define tcp_sendseqinit(tp) \ 165 (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = (tp)->iss 166 167#define TCP_ISSINCR (125*1024) /* increment for tcp_iss each second */ 168 169extern tcp_seq tcp_iss; /* tcp initial send seq # */ 170 171extern const char * const tcpstates[]; 172 173#endif 174