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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)tcp.h 8.1 (Berkeley) 6/10/93 30 * tcp.h,v 1.3 1994/08/21 05:27:34 paul Exp 31 */ 32 33#ifndef _TCP_H_ 34#define _TCP_H_ 35 36typedef uint32_t tcp_seq; 37 38#define PR_SLOWHZ 2 /* 2 slow timeouts per second (approx) */ 39#define PR_FASTHZ 5 /* 5 fast timeouts per second (not important) */ 40 41#define TCP_SNDSPACE 8192 42#define TCP_RCVSPACE 8192 43 44/* 45 * TCP header. 46 * Per RFC 793, September, 1981. 47 */ 48#define tcphdr slirp_tcphdr 49struct tcphdr { 50 uint16_t th_sport; /* source port */ 51 uint16_t th_dport; /* destination port */ 52 tcp_seq th_seq; /* sequence number */ 53 tcp_seq th_ack; /* acknowledgement number */ 54#ifdef HOST_WORDS_BIGENDIAN 55 uint8_t th_off:4, /* data offset */ 56 th_x2:4; /* (unused) */ 57#else 58 uint8_t th_x2:4, /* (unused) */ 59 th_off:4; /* data offset */ 60#endif 61 uint8_t th_flags; 62 uint16_t th_win; /* window */ 63 uint16_t th_sum; /* checksum */ 64 uint16_t th_urp; /* urgent pointer */ 65}; 66 67#include "tcp_var.h" 68 69#ifndef TH_FIN 70#define TH_FIN 0x01 71#define TH_SYN 0x02 72#define TH_RST 0x04 73#define TH_PUSH 0x08 74#define TH_ACK 0x10 75#define TH_URG 0x20 76#endif 77 78#ifndef TCPOPT_EOL 79#define TCPOPT_EOL 0 80#define TCPOPT_NOP 1 81#define TCPOPT_MAXSEG 2 82#define TCPOPT_WINDOW 3 83#define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 84#define TCPOPT_SACK 5 /* Experimental */ 85#define TCPOPT_TIMESTAMP 8 86 87#define TCPOPT_TSTAMP_HDR \ 88 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 89#endif 90 91#ifndef TCPOLEN_MAXSEG 92#define TCPOLEN_MAXSEG 4 93#define TCPOLEN_WINDOW 3 94#define TCPOLEN_SACK_PERMITTED 2 95#define TCPOLEN_TIMESTAMP 10 96#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 97#endif 98 99/* 100 * Default maximum segment size for TCP. 101 * With an IP MSS of 576, this is 536, 102 * but 512 is probably more convenient. 103 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)). 104 * 105 * We make this 1460 because we only care about Ethernet in the qemu context. 106 */ 107#undef TCP_MSS 108#define TCP_MSS 1460 109#undef TCP6_MSS 110#define TCP6_MSS 1440 111 112#undef TCP_MAXWIN 113#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 114 115#undef TCP_MAX_WINSHIFT 116#define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 117 118/* 119 * User-settable options (used with setsockopt). 120 * 121 * We don't use the system headers on unix because we have conflicting 122 * local structures. We can't avoid the system definitions on Windows, 123 * so we undefine them. 124 */ 125#undef TCP_NODELAY 126#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 127#undef TCP_MAXSEG 128 129/* 130 * TCP FSM state definitions. 131 * Per RFC793, September, 1981. 132 */ 133 134#define TCP_NSTATES 11 135 136#define TCPS_CLOSED 0 /* closed */ 137#define TCPS_LISTEN 1 /* listening for connection */ 138#define TCPS_SYN_SENT 2 /* active, have sent syn */ 139#define TCPS_SYN_RECEIVED 3 /* have send and received syn */ 140/* states < TCPS_ESTABLISHED are those where connections not established */ 141#define TCPS_ESTABLISHED 4 /* established */ 142#define TCPS_CLOSE_WAIT 5 /* rcvd fin, waiting for close */ 143/* states > TCPS_CLOSE_WAIT are those where user has closed */ 144#define TCPS_FIN_WAIT_1 6 /* have closed, sent fin */ 145#define TCPS_CLOSING 7 /* closed xchd FIN; await FIN ACK */ 146#define TCPS_LAST_ACK 8 /* had fin and close; await FIN ACK */ 147/* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */ 148#define TCPS_FIN_WAIT_2 9 /* have closed, fin is acked */ 149#define TCPS_TIME_WAIT 10 /* in 2*msl quiet wait after close */ 150 151#define TCPS_HAVERCVDSYN(s) ((s) >= TCPS_SYN_RECEIVED) 152#define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED) 153#define TCPS_HAVERCVDFIN(s) ((s) >= TCPS_TIME_WAIT) 154 155/* 156 * TCP sequence numbers are 32 bit integers operated 157 * on with modular arithmetic. These macros can be 158 * used to compare such integers. 159 */ 160#define SEQ_LT(a,b) ((int)((a)-(b)) < 0) 161#define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0) 162#define SEQ_GT(a,b) ((int)((a)-(b)) > 0) 163#define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0) 164 165/* 166 * Macros to initialize tcp sequence numbers for 167 * send and receive from initial send and receive 168 * sequence numbers. 169 */ 170#define tcp_rcvseqinit(tp) \ 171 (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1 172 173#define tcp_sendseqinit(tp) \ 174 (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = (tp)->iss 175 176#define TCP_ISSINCR (125*1024) /* increment for tcp_iss each second */ 177 178#endif 179