1 /* SPDX-License-Identifier: BSD-3-Clause */ 2 /* 3 * Copyright (c) 1982, 1986, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * @(#)tcp.h 8.1 (Berkeley) 6/10/93 31 * tcp.h,v 1.3 1994/08/21 05:27:34 paul Exp 32 */ 33 34 #ifndef TCP_H 35 #define TCP_H 36 37 #include <glib.h> 38 39 typedef uint32_t tcp_seq; 40 41 #define PR_SLOWHZ 2 /* 2 slow timeouts per second (approx) */ 42 #define PR_FASTHZ 5 /* 5 fast timeouts per second (not important) */ 43 44 #define TCP_SNDSPACE 1024 * 128 45 #define TCP_RCVSPACE 1024 * 128 46 #define TCP_MAXSEG_MAX 32768 47 48 /* 49 * TCP header. 50 * Per RFC 793, September, 1981. 51 */ 52 #define tcphdr slirp_tcphdr 53 struct tcphdr { 54 uint16_t th_sport; /* source port */ 55 uint16_t th_dport; /* destination port */ 56 tcp_seq th_seq; /* sequence number */ 57 tcp_seq th_ack; /* acknowledgement number */ 58 #if G_BYTE_ORDER == G_BIG_ENDIAN 59 uint8_t th_off : 4, /* data offset */ 60 th_x2 : 4; /* (unused) */ 61 #else 62 uint8_t th_x2 : 4, /* (unused) */ 63 th_off : 4; /* data offset */ 64 #endif 65 uint8_t th_flags; 66 uint16_t th_win; /* window */ 67 uint16_t th_sum; /* checksum */ 68 uint16_t th_urp; /* urgent pointer */ 69 }; 70 71 #include "tcp_var.h" 72 73 #ifndef TH_FIN 74 #define TH_FIN 0x01 75 #define TH_SYN 0x02 76 #define TH_RST 0x04 77 #define TH_PUSH 0x08 78 #define TH_ACK 0x10 79 #define TH_URG 0x20 80 #endif 81 82 #ifndef TCPOPT_EOL 83 #define TCPOPT_EOL 0 84 #define TCPOPT_NOP 1 85 #define TCPOPT_MAXSEG 2 86 #define TCPOPT_WINDOW 3 87 #define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 88 #define TCPOPT_SACK 5 /* Experimental */ 89 #define TCPOPT_TIMESTAMP 8 90 91 #define TCPOPT_TSTAMP_HDR \ 92 (TCPOPT_NOP << 24 | TCPOPT_NOP << 16 | TCPOPT_TIMESTAMP << 8 | \ 93 TCPOLEN_TIMESTAMP) 94 #endif 95 96 #ifndef TCPOLEN_MAXSEG 97 #define TCPOLEN_MAXSEG 4 98 #define TCPOLEN_WINDOW 3 99 #define TCPOLEN_SACK_PERMITTED 2 100 #define TCPOLEN_TIMESTAMP 10 101 #define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP + 2) /* appendix A */ 102 #endif 103 104 #undef TCP_MAXWIN 105 #define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 106 107 #undef TCP_MAX_WINSHIFT 108 #define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 109 110 /* 111 * User-settable options (used with setsockopt). 112 * 113 * We don't use the system headers on unix because we have conflicting 114 * local structures. We can't avoid the system definitions on Windows, 115 * so we undefine them. 116 */ 117 #undef TCP_NODELAY 118 #define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 119 #undef TCP_MAXSEG 120 121 /* 122 * TCP FSM state definitions. 123 * Per RFC793, September, 1981. 124 */ 125 126 #define TCP_NSTATES 11 127 128 #define TCPS_CLOSED 0 /* closed */ 129 #define TCPS_LISTEN 1 /* listening for connection */ 130 #define TCPS_SYN_SENT 2 /* active, have sent syn */ 131 #define TCPS_SYN_RECEIVED 3 /* have send and received syn */ 132 /* states < TCPS_ESTABLISHED are those where connections not established */ 133 #define TCPS_ESTABLISHED 4 /* established */ 134 #define TCPS_CLOSE_WAIT 5 /* rcvd fin, waiting for close */ 135 /* states > TCPS_CLOSE_WAIT are those where user has closed */ 136 #define TCPS_FIN_WAIT_1 6 /* have closed, sent fin */ 137 #define TCPS_CLOSING 7 /* closed xchd FIN; await FIN ACK */ 138 #define TCPS_LAST_ACK 8 /* had fin and close; await FIN ACK */ 139 /* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */ 140 #define TCPS_FIN_WAIT_2 9 /* have closed, fin is acked */ 141 #define TCPS_TIME_WAIT 10 /* in 2*msl quiet wait after close */ 142 143 #define TCPS_HAVERCVDSYN(s) ((s) >= TCPS_SYN_RECEIVED) 144 #define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED) 145 #define TCPS_HAVERCVDFIN(s) ((s) >= TCPS_TIME_WAIT) 146 147 /* 148 * TCP sequence numbers are 32 bit integers operated 149 * on with modular arithmetic. These macros can be 150 * used to compare such integers. 151 */ 152 #define SEQ_LT(a, b) ((int)((a) - (b)) < 0) 153 #define SEQ_LEQ(a, b) ((int)((a) - (b)) <= 0) 154 #define SEQ_GT(a, b) ((int)((a) - (b)) > 0) 155 #define SEQ_GEQ(a, b) ((int)((a) - (b)) >= 0) 156 157 /* 158 * Macros to initialize tcp sequence numbers for 159 * send and receive from initial send and receive 160 * sequence numbers. 161 */ 162 #define tcp_rcvseqinit(tp) (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 */ 168 169 #endif 170