slirp/src/tcp.h - qemu - Git at Google

 /* 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 <glib.h>

 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
	/* 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 <glib.h>

	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 2msl 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 (1251024) / increment for tcp_iss each second */

	#endif