tcp_fsm.h

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/*-
 * 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_fsm.h   8.1 (Berkeley) 6/10/93
 * $FreeBSD$
 */
 
#ifndef _NETINET_TCP_FSM_H_
#define _NETINET_TCP_FSM_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 sent 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_CLOSE_WAIT || ((s) >= TCPS_CLOSING && (s) != TCPS_FIN_WAIT_2))
 
#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
 
#ifdef KPROF
int     tcp_acounts[TCP_NSTATES][PRU_NREQ];
#endif
 
#ifdef  TCPSTATES
static char const * const tcpstates[] = {
        "CLOSED",       "LISTEN",       "SYN_SENT",     "SYN_RCVD",
        "ESTABLISHED",  "CLOSE_WAIT",   "FIN_WAIT_1",   "CLOSING",
        "LAST_ACK",     "FIN_WAIT_2",   "TIME_WAIT",
};
#endif
 
#endif