xref: /freebsd/sys/netinet/tcp_fsm.h (revision afe61c15161c324a7af299a9b8457aba5afc92db)
1 /*
2  * Copyright (c) 1982, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)tcp_fsm.h	8.1 (Berkeley) 6/10/93
34  */
35 
36 /*
37  * TCP FSM state definitions.
38  * Per RFC793, September, 1981.
39  */
40 
41 #define	TCP_NSTATES	11
42 
43 #define	TCPS_CLOSED		0	/* closed */
44 #define	TCPS_LISTEN		1	/* listening for connection */
45 #define	TCPS_SYN_SENT		2	/* active, have sent syn */
46 #define	TCPS_SYN_RECEIVED	3	/* have send and received syn */
47 /* states < TCPS_ESTABLISHED are those where connections not established */
48 #define	TCPS_ESTABLISHED	4	/* established */
49 #define	TCPS_CLOSE_WAIT		5	/* rcvd fin, waiting for close */
50 /* states > TCPS_CLOSE_WAIT are those where user has closed */
51 #define	TCPS_FIN_WAIT_1		6	/* have closed, sent fin */
52 #define	TCPS_CLOSING		7	/* closed xchd FIN; await FIN ACK */
53 #define	TCPS_LAST_ACK		8	/* had fin and close; await FIN ACK */
54 /* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */
55 #define	TCPS_FIN_WAIT_2		9	/* have closed, fin is acked */
56 #define	TCPS_TIME_WAIT		10	/* in 2*msl quiet wait after close */
57 
58 #define	TCPS_HAVERCVDSYN(s)	((s) >= TCPS_SYN_RECEIVED)
59 #define	TCPS_HAVERCVDFIN(s)	((s) >= TCPS_TIME_WAIT)
60 
61 #ifdef	TCPOUTFLAGS
62 /*
63  * Flags used when sending segments in tcp_output.
64  * Basic flags (TH_RST,TH_ACK,TH_SYN,TH_FIN) are totally
65  * determined by state, with the proviso that TH_FIN is sent only
66  * if all data queued for output is included in the segment.
67  */
68 u_char	tcp_outflags[TCP_NSTATES] = {
69     TH_RST|TH_ACK, 0, TH_SYN, TH_SYN|TH_ACK,
70     TH_ACK, TH_ACK,
71     TH_FIN|TH_ACK, TH_FIN|TH_ACK, TH_FIN|TH_ACK, TH_ACK, TH_ACK,
72 };
73 #endif
74 
75 #ifdef KPROF
76 int	tcp_acounts[TCP_NSTATES][PRU_NREQ];
77 #endif
78 
79 #ifdef	TCPSTATES
80 char *tcpstates[] = {
81 	"CLOSED",	"LISTEN",	"SYN_SENT",	"SYN_RCVD",
82 	"ESTABLISHED",	"CLOSE_WAIT",	"FIN_WAIT_1",	"CLOSING",
83 	"LAST_ACK",	"FIN_WAIT_2",	"TIME_WAIT",
84 };
85 #endif
86