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/*
* 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.
*
* $Id: sap_output.c,v 1.4 1996/04/13 15:13:24 jhay 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(void)
{
register struct interface *ifp;
struct sockaddr dst;
register struct sockaddr_ipx *ipx_dst;
register 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);
}
}
void
sapsndmsg(dst, flags, ifp)
struct sockaddr *dst;
int flags;
struct interface *ifp;
{
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(dst, flags, ifp, ServType)
struct sockaddr *dst;
int flags;
struct interface *ifp;
int ServType;
{
register struct sap_entry *sap;
register struct sap_entry *csap; /* Clone route */
register struct sap_hash *sh;
register 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(20000);
delay = 0;
}
}
/*
* 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);
}
}
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