/* SPDX-License-Identifier: BSD-3-Clause */ /* * Copyright (c) 1982, 1986, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)tcp.h 8.1 (Berkeley) 6/10/93 * tcp.h,v 1.3 1994/08/21 05:27:34 paul Exp */ #ifndef TCP_H #define TCP_H #include typedef uint32_t tcp_seq; #define PR_SLOWHZ 2 /* 2 slow timeouts per second (approx) */ #define PR_FASTHZ 5 /* 5 fast timeouts per second (not important) */ #define TCP_SNDSPACE 8192 #define TCP_RCVSPACE 8192 /* * TCP header. * Per RFC 793, September, 1981. */ #define tcphdr slirp_tcphdr struct tcphdr { uint16_t th_sport; /* source port */ uint16_t th_dport; /* destination port */ tcp_seq th_seq; /* sequence number */ tcp_seq th_ack; /* acknowledgement number */ #if G_BYTE_ORDER == G_BIG_ENDIAN uint8_t th_off:4, /* data offset */ th_x2:4; /* (unused) */ #else uint8_t th_x2:4, /* (unused) */ th_off:4; /* data offset */ #endif uint8_t th_flags; uint16_t th_win; /* window */ uint16_t th_sum; /* checksum */ uint16_t th_urp; /* urgent pointer */ }; #include "tcp_var.h" #ifndef TH_FIN #define TH_FIN 0x01 #define TH_SYN 0x02 #define TH_RST 0x04 #define TH_PUSH 0x08 #define TH_ACK 0x10 #define TH_URG 0x20 #endif #ifndef TCPOPT_EOL #define TCPOPT_EOL 0 #define TCPOPT_NOP 1 #define TCPOPT_MAXSEG 2 #define TCPOPT_WINDOW 3 #define TCPOPT_SACK_PERMITTED 4 /* Experimental */ #define TCPOPT_SACK 5 /* Experimental */ #define TCPOPT_TIMESTAMP 8 #define TCPOPT_TSTAMP_HDR \ (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) #endif #ifndef TCPOLEN_MAXSEG #define TCPOLEN_MAXSEG 4 #define TCPOLEN_WINDOW 3 #define TCPOLEN_SACK_PERMITTED 2 #define TCPOLEN_TIMESTAMP 10 #define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ #endif /* * Default maximum segment size for TCP. * With an IP MSS of 576, this is 536, * but 512 is probably more convenient. * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)). * * We make this 1460 because we only care about Ethernet in the qemu context. */ #undef TCP_MSS #define TCP_MSS 1460 #undef TCP6_MSS #define TCP6_MSS 1440 #undef TCP_MAXWIN #define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ #undef TCP_MAX_WINSHIFT #define TCP_MAX_WINSHIFT 14 /* maximum window shift */ /* * User-settable options (used with setsockopt). * * We don't use the system headers on unix because we have conflicting * local structures. We can't avoid the system definitions on Windows, * so we undefine them. */ #undef TCP_NODELAY #define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ #undef TCP_MAXSEG /* * TCP FSM state definitions. * Per RFC793, September, 1981. */ #define TCP_NSTATES 11 #define TCPS_CLOSED 0 /* closed */ #define TCPS_LISTEN 1 /* listening for connection */ #define TCPS_SYN_SENT 2 /* active, have sent syn */ #define TCPS_SYN_RECEIVED 3 /* have send and received syn */ /* states < TCPS_ESTABLISHED are those where connections not established */ #define TCPS_ESTABLISHED 4 /* established */ #define TCPS_CLOSE_WAIT 5 /* rcvd fin, waiting for close */ /* states > TCPS_CLOSE_WAIT are those where user has closed */ #define TCPS_FIN_WAIT_1 6 /* have closed, sent fin */ #define TCPS_CLOSING 7 /* closed xchd FIN; await FIN ACK */ #define TCPS_LAST_ACK 8 /* had fin and close; await FIN ACK */ /* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */ #define TCPS_FIN_WAIT_2 9 /* have closed, fin is acked */ #define TCPS_TIME_WAIT 10 /* in 2*msl quiet wait after close */ #define TCPS_HAVERCVDSYN(s) ((s) >= TCPS_SYN_RECEIVED) #define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED) #define TCPS_HAVERCVDFIN(s) ((s) >= TCPS_TIME_WAIT) /* * TCP sequence numbers are 32 bit integers operated * on with modular arithmetic. These macros can be * used to compare such integers. */ #define SEQ_LT(a,b) ((int)((a)-(b)) < 0) #define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0) #define SEQ_GT(a,b) ((int)((a)-(b)) > 0) #define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0) /* * Macros to initialize tcp sequence numbers for * send and receive from initial send and receive * sequence numbers. */ #define tcp_rcvseqinit(tp) \ (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1 #define tcp_sendseqinit(tp) \ (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = (tp)->iss #define TCP_ISSINCR (125*1024) /* increment for tcp_iss each second */ #endif