IPXrouted(8): Re-indent some code to make the outer for() better visible.

[dragonfly.git] / usr.sbin / IPXrouted / sap_output.c

/*
 * Copyright (c) 1995 John Hay.  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 John Hay.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY John Hay 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 John Hay 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.
 *
 * $FreeBSD: src/usr.sbin/IPXrouted/sap_output.c,v 1.9 1999/08/28 01:15:04 peter Exp $
 */

/*
 * Routing Table Management Daemon
 */
#include <unistd.h>
#include "defs.h"

/*
 * Apply the function "f" to all non-passive
 * interfaces.  If the interface supports the
 * use of broadcasting use it, otherwise address
 * the output to the known router.
 */
void
sap_supply_toall(int changesonly)
{
	struct interface *ifp;
	struct sockaddr dst;
	struct sockaddr_ipx *ipx_dst;
	int flags;
	extern struct interface *ifnet;

	ipx_dst = (struct sockaddr_ipx *)&dst;

	for (ifp = ifnet; ifp; ifp = ifp->int_next) {
		if (ifp->int_flags & IFF_PASSIVE)
			continue;

		dst = ifp->int_flags & IFF_BROADCAST ? ifp->int_broadaddr :
		      ifp->int_flags & IFF_POINTOPOINT ? ifp->int_dstaddr :
		      ifp->int_addr;

		ipx_dst->sipx_addr.x_port = htons(IPXPORT_SAP);

		flags = ifp->int_flags & IFF_INTERFACE ? MSG_DONTROUTE : 0;
		sap_supply(&dst, flags, ifp, SAP_WILDCARD, changesonly);
	}
}

void 
sapsndmsg(struct sockaddr *dst, int flags, struct interface *ifp,
	  int changesonly)
{
	struct sockaddr t_dst;
	struct sockaddr_ipx *ipx_dst;

	t_dst = *dst;
	ipx_dst = (struct sockaddr_ipx *)&t_dst;

	if (ipx_dst->sipx_addr.x_port == 0)
		ipx_dst->sipx_addr.x_port = htons(IPXPORT_SAP);

        (*afswitch[dst->sa_family].af_output)
		(sapsock, flags, &t_dst, 
		sizeof (struct sap_packet) + sizeof(u_short));
	TRACE_SAP_OUTPUT(ifp, &t_dst, 
			 sizeof (struct sap_packet) + sizeof(u_short));
}

/*
 * Supply dst with the contents of the SAP tables. If the ServType ==
 * SAP_WILDCARD (0xFFFF) supply the whole table, otherwise only the
 * services that are of ServType. If this won't fit in one packet, chop 
 * it up into several.
 *
 * This must be done using the split horizon algorithm.
 * 1. Don't send SAP info to the interface from where it was received.
 * 2. If a service is received from more than one interface and the cost is
 *    the same, don't publish it on either interface. I am calling this
 *    clones.
 */
void
sap_supply(struct sockaddr *dst, int flags, struct interface *ifp,
	   int ServType, int changesonly)
{
	struct sap_entry *sap;
	struct sap_entry *csap; /* Clone route */
	struct sap_hash *sh;
	struct sap_info *n = sap_msg->sap;
	struct sap_hash *base = sap_head;
	struct sockaddr_ipx *sipx =  (struct sockaddr_ipx *) dst;
	af_output_t *output = afswitch[dst->sa_family].af_output;
	int size, metric;
	int delay = 0;

	if (sipx->sipx_port == 0)
		sipx->sipx_port = htons(IPXPORT_SAP);

	sap_msg->sap_cmd = ntohs(SAP_RESP);

	for (sh = base; sh < &base[SAPHASHSIZ]; sh++) {
		for (sap = sh->forw; sap != (struct sap_entry *)sh;
		     sap = sap->forw) {
			size = (char *)n - (char *)sap_msg;
			if (size >=
			    ((MAXSAPENTRIES * sizeof (struct sap_info)) +
			     sizeof (sap_msg->sap_cmd))) {
				(*output)(sapsock, flags, dst, size);
				TRACE_SAP_OUTPUT(ifp, dst, size);
				n = sap_msg->sap;
				delay++;
				if(delay == 2) {
					usleep(50000);
					delay = 0;
				}
			}

			if (changesonly && !(sap->state & RTS_CHANGED))
				continue;

			/*
			 * Check for the servicetype except if the ServType is
			 * a wildcard (0xFFFF).
			 */
			if ((ServType != SAP_WILDCARD) &&
			    (ServType != sap->sap.ServType))
				continue;

			/*
			 * This should do rule one and two of the split horizon
			 * algorithm.
			 */
			if (sap->ifp == ifp)
				continue;

			/*
			 * Rule 2.
			 * Look if we have clones (different routes to the same
			 * place with exactly the same cost).
			 *
			 * We should not publish on any of the clone
			 * interfaces.
			 */
			csap = sap->clone;
			while (csap) {
				if (csap->ifp == ifp)
					goto next;
				csap = csap->clone;
			}

			/*
			 * Don't advertise services with more than 15 hops. It
			 * will be confused with a service that has gone down.
			 */
			if (ntohs(sap->sap.hops) == (HOPCNT_INFINITY - 1))
				continue;
			metric = min(ntohs(sap->sap.hops) + 1,
			    HOPCNT_INFINITY);

			*n = sap->sap;
			n->hops = htons(metric);
			n++;
next:
			;
		}
		if (n != sap_msg->sap) {
			size = (char *)n - (char *)sap_msg;
			(*output)(sapsock, flags, dst, size);
			TRACE_SAP_OUTPUT(ifp, dst, size);
		}
	}
}