Reviewed by: julian and jhay@mikom.csir.co.za

Submitted by:	Mike Mitchell, supervisor@alb.asctmd.com

This is a bulk mport of Mike's IPX/SPX protocol stacks and all the
related gunf that goes with it..
it is not guaranteed to work 100% correctly at this time
but as we had several people trying to work on it
I figured it would be better to get it checked in so
they could all get teh same thing to work on..

Mikes been using it for a year or so
but on 2.0

more changes and stuff will be merged in from other developers now that this is in.

Mike Mitchell, Network Engineer
AMTECH Systems Corporation, Technology and Manufacturing
8600 Jefferson Street, Albuquerque, New Mexico 87113 (505) 856-8000
supervisor@alb.asctmd.com

1 files changed, 128 insertions, 0 deletions

diff --git a/sys/netipx/spx_timer.h b/sys/netipx/spx_timer.h
new file mode 100644
index 000000000000..ac88eb72ff0e
--- /dev/null
+++ b/sys/netipx/spx_timer.h
@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 1995, Mike Mitchell
+ * Copyright (c) 1982, 1986, 1988, 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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.
+ *
+ *	@(#)spx_timer.h
+ */
+
+#ifndef _NETIPX_SPX_TIMER_H_
+#define _NETIPX_SPX_TIMER_H_
+
+/*
+ * Definitions of the SPX timers.  These timers are counted
+ * down PR_SLOWHZ times a second.
+ */
+#define	SPXT_NTIMERS	4
+
+#define	SPXT_REXMT	0		/* retransmit */
+#define	SPXT_PERSIST	1		/* retransmit persistance */
+#define	SPXT_KEEP	2		/* keep alive */
+#define	SPXT_2MSL	3		/* 2*msl quiet time timer */
+
+/*
+ * The SPXT_REXMT timer is used to force retransmissions.
+ * The SPX has the SPXT_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 SPXT_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 SPXT_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 SPXT_PERSMIN time intervals,
+ * but no more frequently than the current estimate of round-trip
+ * packet time.  The SPXT_PERSIST timer is cleared whenever we receive
+ * a window update from the peer.
+ *
+ * The SPXT_KEEP timer is used to keep connections alive.  If an
+ * connection is idle (no segments received) for SPXTV_KEEP amount of time,
+ * but not yet established, then we drop the connection.  If the connection
+ * is established, then 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 SPXT_KEEP
+ * initiated segments we cannot elicit a response from a peer in SPXT_MAXIDLE
+ * amount of time, then we drop the connection.
+ */
+
+#define	SPX_TTL		30		/* default time to live for SPX segs */
+/*
+ * Time constants.
+ */
+#define	SPXTV_MSL	( 15*PR_SLOWHZ)		/* max seg lifetime */
+#define	SPXTV_SRTTBASE	0			/* base roundtrip time;
+						   if 0, no idea yet */
+#define	SPXTV_SRTTDFLT	(  3*PR_SLOWHZ)		/* assumed RTT if no info */
+
+#define	SPXTV_PERSMIN	(  5*PR_SLOWHZ)		/* retransmit persistance */
+#define	SPXTV_PERSMAX	( 60*PR_SLOWHZ)		/* maximum persist interval */
+
+#define	SPXTV_KEEP	( 75*PR_SLOWHZ)		/* keep alive - 75 secs */
+#define	SPXTV_MAXIDLE	(  8*SPXTV_KEEP)	/* maximum allowable idle
+						   time before drop conn */
+
+#define	SPXTV_MIN	(  1*PR_SLOWHZ)		/* minimum allowable value */
+#define	SPXTV_REXMTMAX	( 64*PR_SLOWHZ)		/* max allowable REXMT value */
+
+#define	SPX_LINGERTIME	120			/* linger at most 2 minutes */
+
+#define	SPX_MAXRXTSHIFT	12			/* maximum retransmits */
+
+#ifdef	SPXTIMERS
+char *spxtimers[] =
+    { "REXMT", "PERSIST", "KEEP", "2MSL" };
+#endif
+
+/*
+ * Force a time value to be in a certain range.
+ */
+#define	SPXT_RANGESET(tv, value, tvmin, tvmax) { \
+	(tv) = (value); \
+	if ((tv) < (tvmin)) \
+		(tv) = (tvmin); \
+	else if ((tv) > (tvmax)) \
+		(tv) = (tvmax); \
+}
+
+#ifdef KERNEL
+extern int spx_backoff[];
+#endif
+
+#endif