tcp_var.h

vxworks 6.x 的全部头文件

/* tcp_var.h - TCP variables and data structures */

/* Copyright 2001-2005 Wind River Systems, Inc. */

/*
 * Copyright (c) 1982, 1986, 1993, 1994, 1995
 *	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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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_var.h	8.4 (Berkeley) 5/24/95
 * $FreeBSD: src/sys/netinet/tcp_var.h,v 1.56.2.12 2002/08/24 18:40:26 dillon Exp $
 */

/*
modification history
--------------------
01y,11aug05,dlk  Disable TTCP support.
01x,27jul05,dlk  Added t_phsum to struct tcpcb.
01w,16jul05,dlk  Add syncache_cleanup() for virtual stack case.
01v,21jun05,dlk  Modify syncache_unreach() to return a value indicating whether
                 a matching syncache entry was located.
01u,16may05,dlk  revert last change (SPR #109227). IP TOS now available in
                 in_conninfo.
01t,09mar05,kc   Changed tcp_rtlookup() and tcp_gettaocache() signature
                 from (struct in_conninfo *) to (struct inpcb *) (SPR#95067).
01s,23feb05,wap  Add tcp_syncache structure (shared betweem tcp_syncache.c and
                 tcp_sysctl.c)
01r,07feb05,vvv  _KERNEL cleanup
01q,31jan05,niq  virtual stack changes for sysctl
01p,13sep04,vvv  renamed path_mtu_discovery to fix Sysctl/virtual stack
                 incompatibility (SPR #91565)
01o,23aug04,rp   merged from COMP_WN_IPV6_BASE6_ITER5_TO_UNIFIED_PRE_MERGE
01n,28may04,niq  Merging from base6 label POST_ITER5_FRZ16_REBASE (ver
                 /main/vdt/base6_itn5_networking-int/1)
01m,06jan04,vvv  changed prototype for tcp_maketemplate (SPR #88742)
01l,20nov03,niq  Remove copyright_wrs.h file inclusion
01k,04nov03,rlm  Ran batch header path update for header re-org.
01j,03nov03,rlm  Removed wrn/coreip/ prefix from #includes for header re-org.
01i,24oct03,cdw  update include statements post header re-org.
01h,08aug03,niq  Merging from Accordion label ACCORDION_BASE6_MERGE_BASELINE
01g,01feb03,pas  merge from FreeBSD 4.7 - added rfc1323, rfc1644 flags,
                 bandwidth limits, syncache
01f,11sep02,hsh  add c++ protection
01e,11sep02,sar  Add updateHeaderSize routine
01d,28mar02,ppp  modifying it to be backward compatible with A.E. 1.1
01c,08feb02,pas  EAR code cleanup
01b,28jan02,ann  uncommenting some code
01a,03dec01,niq  Sysctl changes for Clarinet
01c.29oct01,ham  included callout.h and in_pcb.h.
01b,29oct01,nee  adding inp_tp structure from usrreq.c
01a,13aug01,pas  Created from FreeBSD4.3-RELEASE(July-17-01).
*/

#ifndef _NETINET_TCP_VAR_H_
#define _NETINET_TCP_VAR_H_

/* includes */

#ifdef __cplusplus
extern "C" {
#endif

#undef TTCP
    
#ifdef _WRS_KERNEL
#include <sys/queue.h>
#include <netinet/tcp.h>

/*
 * Kernel variables for tcp.
 */

#ifndef VIRTUAL_STACK
extern int	tcp_do_rfc1323;
#ifdef TTCP
extern int	tcp_do_rfc1644;
#endif
#endif /* VIRTUAL_STACK */

/* TCP segment queue entry */
struct tseg_qent {
	LIST_ENTRY(tseg_qent) tqe_q;
	int	tqe_len;		/* TCP segment data length */
	struct	tcphdr *tqe_th;		/* a pointer to tcp header */
	struct	mbuf	*tqe_m;		/* mbuf contains packet */
};
LIST_HEAD(tsegqe_head, tseg_qent);

/*
 * TCP_REASS_SEG_MULTIPLIER is used to estimate the per-endpoint reassembly
 * queue segment limit. The receive socket buffer size is rounded up to a
 * multiple of the mss, then divided by the mss. That number of segments
 * times TCP_REASS_SEG_MULTIPLIER is the per-endpoint segment limit, unless
 * further restricted by the global limit.
 */

#define TCP_REASS_SEG_MULTIPLIER 4	/* (rcv hiwat/mss) * this is limit */

#define TCP_REASS_COALESCE_MAX	128     /* max bytes to coalesce in reass. Q */

/*
 * This one is problematic. It should be related to the
 * numbers of clusters available in all the various network interface
 * receive pools...
 */
#define TCP_REASS_GLOBAL_SEGMENTS_MAX	512 /* default max segments globally */

typedef struct _TCP_REASS_INFO
    {
    int qmax;   /* maximum number of allowed segments in (all) queue(s) */
    int qsize;	/* current number of segments in (all) queue(s) */
    NET_POOL_ID netPoolId; /* net pool for tseg_qent allocation */
    CL_POOL_ID  clPoolId;  /* cluster pool for tseg_qent allocation */
    int qmax_endpt; /* maximum number of allowed segments per endpoint or -1 */
    u_long      drain_count; /* # of tcp_drain() calls. Move to tcpstat ? */
    } TCP_REASS_INFO;

#define TCP_RQ_ALLOC(x) \
    do  { \
	(x) = (struct tseg_qent *)clusterGet (tcp_reass_info.netPoolId, \
				              tcp_reass_info.clPoolId); \
	} while (0)

#define TCP_RQ_FREE(x) \
    do  { \
	clFree (tcp_reass_info.netPoolId, (char *)(x));	\
	} while (0)

struct tcptemp {
	u_char	tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */
	struct	tcphdr tt_t;
};

#define tcp6cb		tcpcb  /* for KAME src sync over BSD*'s */

#include <sys/callout.h>
#include <sys/socket.h>                 /* XXX included for in_pcb.h */
#include <net/socketvar.h>
#include <netinet/in.h>           /* XXX included for in_pcb.h */
#include <netinet/in_pcb.h> 

/*
 * Tcp control block, one per tcp; fields:
 * Organized for 16 byte cacheline efficiency.
 */
struct tcpcb {
	struct	tsegqe_head t_segq;
	int t_reass_qsize;
	int t_reass_qmax;

	struct	callout *tt_rexmt;	/* retransmit timer */
	struct	callout *tt_persist;	/* retransmit persistence */
	struct	callout *tt_keep;	/* keepalive */
	struct	callout *tt_2msl;	/* 2*msl TIME_WAIT timer */
	struct	callout *tt_delack;	/* delayed ACK timer */

	struct	inpcb *t_inpcb;		/* back pointer to internet pcb */
	int	t_state;		/* state of this connection */
	u_int	t_flags;
#define	TF_ACKNOW	0x00001		/* ack peer immediately */
#define	TF_DELACK	0x00002		/* ack, but try to delay it */
#define	TF_NODELAY	0x00004		/* don't delay packets to coalesce */
#define	TF_NOOPT	0x00008		/* don't use tcp options */
#define	TF_SENTFIN	0x00010		/* have sent FIN */
#define	TF_REQ_SCALE	0x00020		/* have/will request window scaling */
#define	TF_RCVD_SCALE	0x00040		/* other side has requested scaling */
#define	TF_REQ_TSTMP	0x00080		/* have/will request timestamps */
#define	TF_RCVD_TSTMP	0x00100		/* a timestamp was received in SYN */
#define	TF_SACK_PERMIT	0x00200		/* other side said I could SACK */
#define	TF_NEEDSYN	0x00400		/* send SYN (implicit state) */
#define	TF_NEEDFIN	0x00800		/* send FIN (implicit state) */
#define	TF_NOPUSH	0x01000		/* don't push */
#define	TF_REQ_CC	0x02000		/* have/will request CC */
#define	TF_RCVD_CC	0x04000		/* a CC was received in SYN */
#define	TF_SENDCCNEW	0x08000		/* send CCnew instead of CC in SYN */
#define	TF_MORETOCOME	0x10000		/* More data to be appended to sock */
#define	TF_LQ_OVERFLOW	0x20000		/* listen queue overflow */
#define	TF_NAGLE_CREDIT	0x40000		/* connection was previously idle */
#define TF_RXWIN0SENT	0x80000		/* sent a receiver win 0 in response */
	int	t_force;		/* 1 if forcing out a byte */

	tcp_seq	snd_una;		/* send unacknowledged */
	tcp_seq	snd_max;		/* highest sequence number sent;
					 * used to recognize retransmits
					 */
	tcp_seq	snd_nxt;		/* send next */
	tcp_seq	snd_up;			/* send urgent pointer */

	tcp_seq	snd_wl1;		/* window update seg seq number */
	tcp_seq	snd_wl2;		/* window update seg ack number */
	tcp_seq	iss;			/* initial send sequence number */
	tcp_seq	irs;			/* initial receive sequence number */

	tcp_seq	rcv_nxt;		/* receive next */
	tcp_seq	rcv_adv;		/* advertised window */
	u_long	rcv_wnd;		/* receive window */
	tcp_seq	rcv_up;			/* receive urgent pointer */

	u_long	snd_wnd;		/* send window */
	u_long	snd_cwnd;		/* congestion-controlled window */
	u_long	snd_bwnd;		/* bandwidth-controlled window */
	u_long	snd_ssthresh;		/* snd_cwnd size threshold for
					 * for slow start exponential to
					 * linear switch
					 */
	u_long	snd_bandwidth;		/* calculated bandwidth or 0 */
	tcp_seq	snd_recover;		/* for use in fast recovery */

	int	t_dupacks;		/* consecutive dup acks recd */

	u_int	t_maxopd;		/* mss plus options */

	u_long	t_rcvtime;		/* inactivity time */
	u_long	t_starttime;		/* time connection was established */
	int	t_rtttime;		/* round trip time */
	tcp_seq	t_rtseq;		/* sequence number being timed */

	int	t_bw_rtttime;		/* used for bandwidth calculation */
	tcp_seq	t_bw_rtseq;		/* used for bandwidth calculation */

	int	t_rxtcur;		/* current retransmit value (ticks) */
	u_int	t_maxseg;		/* maximum segment size */
	int	t_srtt;			/* smoothed round-trip time */
	int	t_rttvar;		/* variance in round-trip time */

	int	t_rxtshift;		/* log(2) of rexmt exp. backoff */
	u_int	t_rttmin;		/* minimum rtt allowed */
	u_int	t_rttbest;		/* best rtt we've seen */
	u_long	t_rttupdated;		/* number of times rtt sampled */
	u_long	max_sndwnd;		/* largest window peer has offered */

	int	t_softerror;		/* possible error not yet reported */
/* out-of-band data */
	char	t_oobflags;		/* have some */
	char	t_iobc;			/* input character */
#define	TCPOOB_HAVEDATA	0x01
#define	TCPOOB_HADDATA	0x02
/* RFC 1323 variables */
	u_char	snd_scale;		/* window scaling for send window */
	u_char	rcv_scale;		/* window scaling for recv window */
	u_char	request_r_scale;	/* pending window scaling */
	u_char	requested_s_scale;
	u_int16_t t_phsum;		/* cached pseudo-header sum w/o len */
	u_long	ts_recent;		/* timestamp echo data */

	u_long	ts_recent_age;		/* when last updated */
	tcp_seq	last_ack_sent;

#ifdef TTCP
/* RFC 1644 variables */
	tcp_cc	cc_send;		/* send connection count */
	tcp_cc	cc_recv;		/* receive connection count */
#endif /* TTCP */

/* experimental */
	u_long	snd_cwnd_prev;		/* cwnd prior to retransmit */
	u_long	snd_ssthresh_prev;	/* ssthresh prior to retransmit */
	u_long	t_badrxtwin;		/* window for retransmit recovery */
};

/*
 * Structure to hold TCP options that are only used during segment
 * processing (in tcp_input), but not held in the tcpcb.
 * It's basically used to reduce the number of parameters
 * to tcp_dooptions.
 */
struct tcpopt {
	u_long		to_flags;	/* which options are present */
#define TOF_TS		0x0001		/* timestamp */
#define TOF_CC		0x0002		/* CC and CCnew are exclusive */
#define TOF_CCNEW	0x0004
#define	TOF_CCECHO	0x0008
#define	TOF_MSS		0x0010
#define	TOF_SCALE	0x0020
	u_int32_t	to_tsval;
	u_int32_t	to_tsecr;
	tcp_cc		to_cc;		/* holds CC or CCnew */
	tcp_cc		to_ccecho;
	u_int16_t	to_mss;
	u_int8_t 	to_requested_s_scale;
	u_int8_t 	to_pad;
};

struct syncache {
	inp_gen_t	sc_inp_gencnt;		/* pointer check */
	struct 		tcpcb *sc_tp;		/* tcb for listening socket */
	struct		mbuf *sc_ipopts;	/* source route */
	struct 		in_conninfo sc_inc;	/* addresses */
#define sc_route	sc_inc.inc_route
#define sc_route6	sc_inc.inc6_route
	u_int32_t	sc_tsrecent;
#ifdef TTCP
	tcp_cc		sc_cc_send;		/* holds CC or CCnew */
	tcp_cc		sc_cc_recv;
#endif
	tcp_seq 	sc_irs;			/* seq from peer */
	tcp_seq 	sc_iss;			/* our ISS */
	u_long		sc_rxttime;		/* retransmit time */
	u_int16_t	sc_rxtslot; 		/* retransmit counter */
	u_int16_t	sc_peer_mss;		/* peer's MSS */
	u_int16_t	sc_wnd;			/* advertised window */
	u_int8_t 	sc_requested_s_scale:4,
			sc_request_r_scale:4;
	u_int8_t	sc_flags;
#define SCF_NOOPT	0x01			/* no TCP options */
#define SCF_WINSCALE	0x02			/* negotiated window scaling */
#define SCF_TIMESTAMP	0x04			/* negotiated timestamps */
#define SCF_CC		0x08			/* negotiated CC */
#define SCF_UNREACH	0x10			/* icmp unreachable received */
#define SCF_KEEPROUTE	0x20			/* keep cloned route */
	TAILQ_ENTRY(syncache)	sc_hash;
	TAILQ_ENTRY(syncache)	sc_timerq;
};