1 /*        $NetBSD: tcp_fsm.h,v 1.16 2018/04/07 13:48:50 maxv Exp $    */
2 
3 /*
4  * Copyright (c) 1982, 1986, 1993
5  *        The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *        @(#)tcp_fsm.h       8.1 (Berkeley) 6/10/93
32  */
33 
34 #ifndef _NETINET_TCP_FSM_H_
35 #define _NETINET_TCP_FSM_H_
36 
37 /*
38  * TCP FSM state definitions.
39  * Per RFC793, September, 1981.
40  */
41 
42 #define   TCP_NSTATES         11
43 
44 #define   TCPS_CLOSED                   0         /* closed */
45 #define   TCPS_LISTEN                   1         /* listening for connection */
46 #define   TCPS_SYN_SENT                 2         /* active, have sent syn */
47 #define   TCPS_SYN_RECEIVED   3         /* have send and received syn */
48 /* states < TCPS_ESTABLISHED are those where connections not established */
49 #define   TCPS_ESTABLISHED    4         /* established */
50 #define   TCPS_CLOSE_WAIT               5         /* rcvd fin, waiting for close */
51 /* states > TCPS_CLOSE_WAIT are those where user has closed */
52 #define   TCPS_FIN_WAIT_1               6         /* have closed, sent fin */
53 #define   TCPS_CLOSING                  7         /* closed xchd FIN; await ACK */
54 #define   TCPS_LAST_ACK                 8         /* had fin and close; await FIN ACK */
55 /* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */
56 #define   TCPS_FIN_WAIT_2               9         /* have closed, fin is acked */
57 #define   TCPS_TIME_WAIT                10        /* in 2*msl quiet wait after close */
58 
59 #define   TCPS_HAVERCVDSYN(s) ((s) >= TCPS_SYN_RECEIVED)
60 #define   TCPS_HAVEESTABLISHED(s)       ((s) >= TCPS_ESTABLISHED)
61 #define   TCPS_HAVERCVDFIN(s) \
62     ((s) == TCPS_CLOSE_WAIT || ((s) >= TCPS_CLOSING && (s) != TCPS_FIN_WAIT_2))
63 
64 #ifdef    TCPOUTFLAGS
65 /*
66  * Flags used when sending segments in tcp_output.
67  * Basic flags (TH_RST,TH_ACK,TH_SYN,TH_FIN) are totally
68  * determined by state, with the proviso that TH_FIN is sent only
69  * if all data queued for output is included in the segment.
70  */
71 const u_char        tcp_outflags[TCP_NSTATES] = {
72           TH_RST|TH_ACK,      /* CLOSED */
73           0,                  /* LISTEN */
74           TH_SYN,             /* SYN_SENT */
75           TH_SYN|TH_ACK,      /* SYN_RCVD */
76           TH_ACK,             /* ESTABLISHED */
77           TH_ACK,             /* CLOSE_WAIT */
78           TH_FIN|TH_ACK,      /* FIN_WAIT_1 */
79           TH_FIN|TH_ACK,      /* CLOSING */
80           TH_FIN|TH_ACK,      /* LAST_ACK */
81           TH_ACK,             /* FIN_WAIT_2 */
82           TH_ACK,             /* TIME_WAIT */
83 };
84 #endif
85 
86 #ifdef    TCPSTATES
87 const char * const tcpstates[] = {
88           "CLOSED", "LISTEN", "SYN_SENT",         "SYN_RCVD",
89           "ESTABLISHED",      "CLOSE_WAIT",       "FIN_WAIT_1",       "CLOSING",
90           "LAST_ACK",         "FIN_WAIT_2",       "TIME_WAIT",
91 };
92 #elif defined(_KERNEL)
93 extern const char * const tcpstates[];
94 #endif
95 
96 #endif /* !_NETINET_TCP_FSM_H_ */
97