b91b1cdbb2
to break free of the constraint if the range minimum boundary is larger than the maximum boundary. Discovered by jmg@FreeBSD.org. (See FreeBSD's tcp_timer.h rev 1.31).
197 lines
8.3 KiB
C
197 lines
8.3 KiB
C
/* $NetBSD: tcp_timer.h,v 1.24 2006/09/26 06:39:22 jeremy Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 2001, 2005 The NetBSD Foundation, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to The NetBSD Foundation
|
|
* by Jason R. Thorpe of Wasabi Systems, Inc.
|
|
* This code is derived from software contributed to The NetBSD Foundation
|
|
* by Charles M. Hannum.
|
|
*
|
|
* 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 NetBSD
|
|
* Foundation, Inc. and its contributors.
|
|
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
|
|
*/
|
|
|
|
/*
|
|
* 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_timer.h 8.1 (Berkeley) 6/10/93
|
|
*/
|
|
|
|
#ifndef _NETINET_TCP_TIMER_H_
|
|
#define _NETINET_TCP_TIMER_H_
|
|
|
|
/*
|
|
* Definitions of the TCP timers. These timers are counted
|
|
* down PR_SLOWHZ times a second.
|
|
*/
|
|
#define TCPT_NTIMERS 4
|
|
|
|
#define TCPT_REXMT 0 /* retransmit */
|
|
#define TCPT_PERSIST 1 /* retransmit persistance */
|
|
#define TCPT_KEEP 2 /* keep alive */
|
|
#define TCPT_2MSL 3 /* 2*msl quiet time timer */
|
|
|
|
/*
|
|
* The TCPT_REXMT timer is used to force retransmissions.
|
|
* The TCP has the TCPT_REXMT timer set whenever segments
|
|
* have been sent for which ACKs are expected but not yet
|
|
* received. If an ACK is received which advances tp->snd_una,
|
|
* then the retransmit timer is cleared (if there are no more
|
|
* outstanding segments) or reset to the base value (if there
|
|
* are more ACKs expected). Whenever the retransmit timer goes off,
|
|
* we retransmit one unacknowledged segment, and do a backoff
|
|
* on the retransmit timer.
|
|
*
|
|
* The TCPT_PERSIST timer is used to keep window size information
|
|
* flowing even if the window goes shut. If all previous transmissions
|
|
* have been acknowledged (so that there are no retransmissions in progress),
|
|
* and the window is too small to bother sending anything, then we start
|
|
* the TCPT_PERSIST timer. When it expires, if the window is nonzero,
|
|
* we go to transmit state. Otherwise, at intervals send a single byte
|
|
* into the peer's window to force him to update our window information.
|
|
* We do this at most as often as TCPT_PERSMIN time intervals,
|
|
* but no more frequently than the current estimate of round-trip
|
|
* packet time. The TCPT_PERSIST timer is cleared whenever we receive
|
|
* a window update from the peer.
|
|
*
|
|
* The TCPT_KEEP timer is used to keep connections alive. If an
|
|
* connection is idle (no segments received) for TCPTV_KEEP_INIT amount of time,
|
|
* but not yet established, then we drop the connection. Once the connection
|
|
* is established, if the connection is idle for TCPTV_KEEP_IDLE time
|
|
* (and keepalives have been enabled on the socket), we begin to probe
|
|
* the connection. We force the peer to send us a segment by sending:
|
|
* <SEQ=SND.UNA-1><ACK=RCV.NXT><CTL=ACK>
|
|
* This segment is (deliberately) outside the window, and should elicit
|
|
* an ack segment in response from the peer. If, despite the TCPT_KEEP
|
|
* initiated segments we cannot elicit a response from a peer in TCPT_MAXIDLE
|
|
* amount of time probing, then we drop the connection.
|
|
*/
|
|
|
|
/*
|
|
* Time constants.
|
|
*/
|
|
#define TCPTV_MSL ( 30*PR_SLOWHZ) /* max seg lifetime (hah!) */
|
|
#define TCPTV_SRTTBASE 0 /* base roundtrip time;
|
|
if 0, no idea yet */
|
|
#define TCPTV_SRTTDFLT ( 3*PR_SLOWHZ) /* assumed RTT if no info */
|
|
|
|
#define TCPTV_PERSMIN ( 5*PR_SLOWHZ) /* retransmit persistance */
|
|
#define TCPTV_PERSMAX ( 60*PR_SLOWHZ) /* maximum persist interval */
|
|
|
|
#define TCPTV_KEEP_INIT ( 75*PR_SLOWHZ) /* initial connect keep alive */
|
|
#define TCPTV_KEEP_IDLE (120*60*PR_SLOWHZ) /* dflt time before probing */
|
|
#define TCPTV_KEEPINTVL ( 75*PR_SLOWHZ) /* default probe interval */
|
|
#define TCPTV_KEEPCNT 8 /* max probes before drop */
|
|
|
|
#define TCPTV_MIN ( 1*PR_SLOWHZ) /* minimum allowable value */
|
|
#define TCPTV_REXMTMAX ( 64*PR_SLOWHZ) /* max allowable REXMT value */
|
|
|
|
#define TCP_LINGERTIME 120 /* linger at most 2 minutes */
|
|
|
|
#define TCP_MAXRXTSHIFT 12 /* maximum retransmits */
|
|
|
|
#define TCP_DELACK_TICKS (hz / PR_FASTHZ) /* time to delay ACK */
|
|
|
|
#ifdef TCPTIMERS
|
|
const char *tcptimers[] =
|
|
{ "REXMT", "PERSIST", "KEEP", "2MSL" };
|
|
#endif
|
|
|
|
/*
|
|
* Init, arm, disarm, and test TCP timers.
|
|
*/
|
|
#define TCP_TIMER_INIT(tp, timer) \
|
|
callout_setfunc(&(tp)->t_timer[(timer)], \
|
|
tcp_timer_funcs[(timer)], (tp))
|
|
|
|
#define TCP_TIMER_ARM(tp, timer, nticks) \
|
|
callout_schedule(&(tp)->t_timer[(timer)], \
|
|
(nticks) * (hz / PR_SLOWHZ))
|
|
|
|
#define TCP_TIMER_DISARM(tp, timer) \
|
|
callout_stop(&(tp)->t_timer[(timer)])
|
|
|
|
#define TCP_TIMER_ISARMED(tp, timer) \
|
|
callout_active(&(tp)->t_timer[(timer)])
|
|
|
|
/*
|
|
* Force a time value to be in a certain range.
|
|
*/
|
|
#define TCPT_RANGESET(tv, value, tvmin, tvmax) { \
|
|
(tv) = (value); \
|
|
if ((tv) < (tvmin)) \
|
|
(tv) = (tvmin); \
|
|
if ((tv) > (tvmax)) \
|
|
(tv) = (tvmax); \
|
|
}
|
|
|
|
#ifdef _KERNEL
|
|
typedef void (*tcp_timer_func_t)(void *);
|
|
|
|
extern const tcp_timer_func_t tcp_timer_funcs[TCPT_NTIMERS];
|
|
|
|
extern int tcp_keepidle; /* time before keepalive probes begin */
|
|
extern int tcp_keepintvl; /* time between keepalive probes */
|
|
extern int tcp_keepcnt; /* number of keepalives, 0=infty */
|
|
extern int tcp_maxpersistidle; /* max idle time in persist */
|
|
extern int tcp_maxidle; /* time to drop after starting probes */
|
|
extern int tcp_ttl; /* time to live for TCP segs */
|
|
extern const int tcp_backoff[];
|
|
|
|
void tcp_timer_init(void);
|
|
#endif
|
|
|
|
#endif /* !_NETINET_TCP_TIMER_H_ */
|