sys/netinet/tcp_fsm.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1982, 1986, 1993
   5  *      The Regents of the University of California.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  *      @(#)tcp_fsm.h   8.1 (Berkeley) 6/10/93
  33  * $FreeBSD$
  34  */
  35
  36 #ifndef _NETINET_TCP_FSM_H_
  37 #define _NETINET_TCP_FSM_H_
  38
  39 /*
  40  * TCP FSM state definitions.
  41  *
  42  * Per RFC793, September, 1981.
  43  */
  44
  45 #define TCP_NSTATES     11
  46
  47 #define TCPS_CLOSED             0       /* closed */
  48 #define TCPS_LISTEN             1       /* listening for connection */
  49 #define TCPS_SYN_SENT           2       /* active, have sent syn */
  50 #define TCPS_SYN_RECEIVED       3       /* have sent and received syn */
  51 /* states < TCPS_ESTABLISHED are those where connections not established */
  52 #define TCPS_ESTABLISHED        4       /* established */
  53 #define TCPS_CLOSE_WAIT         5       /* rcvd fin, waiting for close */
  54 /* states > TCPS_CLOSE_WAIT are those where user has closed */
  55 #define TCPS_FIN_WAIT_1         6       /* have closed, sent fin */
  56 #define TCPS_CLOSING            7       /* closed xchd FIN; await FIN ACK */
  57 #define TCPS_LAST_ACK           8       /* had fin and close; await FIN ACK */
  58 /* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */
  59 #define TCPS_FIN_WAIT_2         9       /* have closed, fin is acked */
  60 #define TCPS_TIME_WAIT          10      /* in 2*msl quiet wait after close */
  61
  62 /* for KAME src sync over BSD*'s */
  63 #define TCP6_NSTATES            TCP_NSTATES
  64 #define TCP6S_CLOSED            TCPS_CLOSED
  65 #define TCP6S_LISTEN            TCPS_LISTEN
  66 #define TCP6S_SYN_SENT          TCPS_SYN_SENT
  67 #define TCP6S_SYN_RECEIVED      TCPS_SYN_RECEIVED
  68 #define TCP6S_ESTABLISHED       TCPS_ESTABLISHED
  69 #define TCP6S_CLOSE_WAIT        TCPS_CLOSE_WAIT
  70 #define TCP6S_FIN_WAIT_1        TCPS_FIN_WAIT_1
  71 #define TCP6S_CLOSING           TCPS_CLOSING
  72 #define TCP6S_LAST_ACK          TCPS_LAST_ACK
  73 #define TCP6S_FIN_WAIT_2        TCPS_FIN_WAIT_2
  74 #define TCP6S_TIME_WAIT         TCPS_TIME_WAIT
  75
  76 #define TCPS_HAVERCVDSYN(s)     ((s) >= TCPS_SYN_RECEIVED)
  77 #define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED)
  78 #define TCPS_HAVERCVDFIN(s)     \
  79     ((s) == TCPS_CLOSE_WAIT || ((s) >= TCPS_CLOSING && (s) != TCPS_FIN_WAIT_2))
  80
  81 #ifdef  TCPOUTFLAGS
  82 /*
  83  * Flags used when sending segments in tcp_output.  Basic flags (TH_RST,
  84  * TH_ACK,TH_SYN,TH_FIN) are totally determined by state, with the proviso
  85  * that TH_FIN is sent only if all data queued for output is included in the
  86  * segment.
  87  */
  88 static u_char   tcp_outflags[TCP_NSTATES] = {
  89         TH_RST|TH_ACK,          /* 0, CLOSED */
  90         0,                      /* 1, LISTEN */
  91         TH_SYN,                 /* 2, SYN_SENT */
  92         TH_SYN|TH_ACK,          /* 3, SYN_RECEIVED */
  93         TH_ACK,                 /* 4, ESTABLISHED */
  94         TH_ACK,                 /* 5, CLOSE_WAIT */
  95         TH_FIN|TH_ACK,          /* 6, FIN_WAIT_1 */
  96         TH_FIN|TH_ACK,          /* 7, CLOSING */
  97         TH_FIN|TH_ACK,          /* 8, LAST_ACK */
  98         TH_ACK,                 /* 9, FIN_WAIT_2 */
  99         TH_ACK,                 /* 10, TIME_WAIT */
 100 };
 101 #endif
 102
 103 #ifdef KPROF
 104 int     tcp_acounts[TCP_NSTATES][PRU_NREQ];
 105 #endif
 106
 107 #ifdef  TCPSTATES
 108 static char const * const tcpstates[] = {
 109         "CLOSED",       "LISTEN",       "SYN_SENT",     "SYN_RCVD",
 110         "ESTABLISHED",  "CLOSE_WAIT",   "FIN_WAIT_1",   "CLOSING",
 111         "LAST_ACK",     "FIN_WAIT_2",   "TIME_WAIT",
 112 };
 113 #endif
 114
 115 #endif