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/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * 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. 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_fsm.h	8.1 (Berkeley) 6/10/93
 * $FreeBSD: src/sys/netinet/tcp_fsm.h,v 1.14 1999/11/07 04:18:30 jlemon Exp $
 */

#ifndef _NETINET_TCP_FSM_H_
#define _NETINET_TCP_FSM_H_
#include <sys/appleapiopts.h>

/*
 * 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 */

/* for KAME src sync over BSD*'s */
#define TCP6_NSTATES            TCP_NSTATES
#define TCP6S_CLOSED            TCPS_CLOSED
#define TCP6S_LISTEN            TCPS_LISTEN
#define TCP6S_SYN_SENT          TCPS_SYN_SENT
#define TCP6S_SYN_RECEIVED      TCPS_SYN_RECEIVED
#define TCP6S_ESTABLISHED       TCPS_ESTABLISHED
#define TCP6S_CLOSE_WAIT        TCPS_CLOSE_WAIT
#define TCP6S_FIN_WAIT_1        TCPS_FIN_WAIT_1
#define TCP6S_CLOSING           TCPS_CLOSING
#define TCP6S_LAST_ACK          TCPS_LAST_ACK
#define TCP6S_FIN_WAIT_2        TCPS_FIN_WAIT_2
#define TCP6S_TIME_WAIT         TCPS_TIME_WAIT

#define TCPS_HAVERCVDSYN(s)     ((s) >= TCPS_SYN_RECEIVED)
#define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED)
#define TCPS_HAVERCVDFIN(s)     ((s) >= TCPS_TIME_WAIT)
#define TCPS_HAVERCVDFIN2(s)    ((s) == TCPS_CLOSE_WAIT ||                      \
	                         (s) == TCPS_CLOSING ||                         \
	                         (s) == TCPS_LAST_ACK ||                        \
	                         (s) == TCPS_TIME_WAIT)

#ifdef KERNEL_PRIVATE
#ifdef  TCPOUTFLAGS
/*
 * Flags used when sending segments in tcp_output.
 * Basic flags (TH_RST,TH_ACK,TH_SYN,TH_FIN) are totally
 * determined by state, with the proviso that TH_FIN is sent only
 * if all data queued for output is included in the segment.
 */
static u_char   tcp_outflags[TCP_NSTATES] = {
	TH_RST | TH_ACK,          /* 0, CLOSED */
	0,                      /* 1, LISTEN */
	TH_SYN,                 /* 2, SYN_SENT */
	TH_SYN | TH_ACK,          /* 3, SYN_RECEIVED */
	TH_ACK,                 /* 4, ESTABLISHED */
	TH_ACK,                 /* 5, CLOSE_WAIT */
	TH_FIN | TH_ACK,          /* 6, FIN_WAIT_1 */
	TH_FIN | TH_ACK,          /* 7, CLOSING */
	TH_FIN | TH_ACK,          /* 8, LAST_ACK */
	TH_ACK,                 /* 9, FIN_WAIT_2 */
	TH_ACK,                 /* 10, TIME_WAIT */
};
#endif
#endif /* KERNEL_PRIVATE */

#if KPROF
#ifdef KERNEL_PRIVATE
int     tcp_acounts[TCP_NSTATES][PRU_NREQ];
#endif /* KERNEL_PRIVATE */
#endif

#ifdef  TCPSTATES
char *tcpstates[] = {
	"CLOSED", "LISTEN", "SYN_SENT", "SYN_RCVD",
	"ESTABLISHED", "CLOSE_WAIT", "FIN_WAIT_1", "CLOSING",
	"LAST_ACK", "FIN_WAIT_2", "TIME_WAIT"
};
#endif

#endif