4.3BSD/usr/src/etc/XNSrouted/main.c

/*
 * Copyright (c) 1985 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 *
 * Includes material written at Cornell University by Bill Nesheim
 * with permission of the author.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1983 Regents of the University of California.\n\
 All rights reserved.\n";
#endif not lint

#ifndef lint
static char sccsid[] = "@(#)main.c	5.5 (Berkeley) 2/14/86";
#endif not lint

/*
 * XNS Routing Information Protocol Daemon
 */
#include "defs.h"
#include <sys/ioctl.h>
#include <sys/time.h>

#include <net/if.h>

#include <errno.h>
#include <nlist.h>
#include <signal.h>

int	supplier = -1;		/* process should supply updates */
extern int gateway;

struct	rip *msg = (struct rip *) &packet[sizeof (struct idp)]; 
int	hup(), fkexit();

main(argc, argv)
	int argc;
	char *argv[];
{
	int cc;
	struct sockaddr from;
	u_char retry;
	
	argv0 = argv;
	argv++, argc--;
	while (argc > 0 && **argv == '-') {
		if (strcmp(*argv, "-s") == 0) {
			supplier = 1;
			argv++, argc--;
			continue;
		}
		if (strcmp(*argv, "-q") == 0) {
			supplier = 0;
			argv++, argc--;
			continue;
		}
		if (strcmp(*argv, "-R") == 0) {
			noteremoterequests++;
			argv++, argc--;
			continue;
		}
		if (strcmp(*argv, "-t") == 0) {
			tracepackets++;
			argv++, argc--;
			ftrace = stderr;
			tracing = 1; 
			continue;
		}
		if (strcmp(*argv, "-g") == 0) {
			gateway = 1;
			argv++, argc--;
			continue;
		}
		if (strcmp(*argv, "-l") == 0) {
			gateway = -1;
			argv++, argc--;
			continue;
		}
		fprintf(stderr,
			"usage: xnsrouted [ -s ] [ -q ] [ -t ] [ -g ] [ -l ]\n");
		exit(1);
	}
	
	
#ifndef DEBUG
	if (!tracepackets) {
		int t;

		if (fork())
			exit(0);
		for (t = 0; t < 20; t++)
			(void) close(t);
		(void) open("/", 0);
		(void) dup2(0, 1);
		(void) dup2(0, 2);
		t = open("/dev/tty", 2);
		if (t >= 0) {
			ioctl(t, TIOCNOTTY, (char *)0);
			(void) close(t);
		}
	}
#endif
	openlog("XNSrouted", LOG_PID, LOG_DAEMON);

	ns_anynet.s_net[0] = -1; ns_anynet.s_net[1] = -1;
	addr.sns_family = AF_NS;
	addr.sns_port = htons(IDPPORT_RIF);
	s = getsocket(SOCK_DGRAM, 0, &addr);
	if (s < 0)
		exit(1);
	/*
	 * Any extra argument is considered
	 * a tracing log file.
	 */
	if (argc > 0)
		traceon(*argv);
	/*
	 * Collect an initial view of the world by
	 * snooping in the kernel.  Then, send a request packet on all
	 * directly connected networks to find out what
	 * everyone else thinks.
	 */
	rtinit();
	ifinit();
	if (supplier < 0)
		supplier = 0;
	/* request the state of the world */
	msg->rip_cmd = htons(RIPCMD_REQUEST);
	msg->rip_nets[0].rip_dst = ns_anynet;
	msg->rip_nets[0].rip_metric =  htons(HOPCNT_INFINITY);
	toall(sendmsg);
	signal(SIGALRM, timer);
	signal(SIGHUP, hup);
	signal(SIGINT, hup);
	signal(SIGEMT, fkexit);
	timer();
	

	for (;;) 
		process(s);
	
}

process(fd)
	int fd;
{
	struct sockaddr from;
	int fromlen = sizeof (from), cc, omask;
	struct idp *idp = (struct idp *)packet;

	cc = recvfrom(fd, packet, sizeof (packet), 0, &from, &fromlen);
	if (cc <= 0) {
		if (cc < 0 && errno != EINTR)
			syslog("recvfrom: %m");
		return;
	}
	if (tracepackets > 1 && ftrace) {
	    fprintf(ftrace,"rcv %d bytes on %s ", cc, xns_ntoa(&idp->idp_dna));
	    fprintf(ftrace," from %s\n", xns_ntoa(&idp->idp_sna));
	}
	
	if (noteremoterequests && !ns_neteqnn(idp->idp_sna.x_net, ns_zeronet)
		&& !ns_neteq(idp->idp_sna, idp->idp_dna))
	{
		syslog(LOG_ERR,
		       "net of interface (%s) != net on ether (%s)!\n",
		       xns_nettoa(idp->idp_dna.x_net),
		       xns_nettoa(idp->idp_sna.x_net));
	}
			
	/* We get the IDP header in front of the RIF packet*/
	cc -= sizeof (struct idp);
#define	mask(s)	(1<<((s)-1))
	omask = sigblock(mask(SIGALRM));
	rip_input(&from, cc);
	sigsetmask(omask);
}

getsocket(type, proto, sns)
	int type, proto; 
	struct sockaddr_ns *sns;
{
	int domain = sns->sns_family;
	int retry, s, on = 1;

	retry = 1;
	while ((s = socket(domain, type, proto)) < 0 && retry) {
		syslog("socket: %m");
		sleep(5 * retry);
		retry <<= 1;
	}
	if (retry == 0)
		return (-1);
	while (bind(s, sns, sizeof (*sns), 0) < 0 && retry) {
		syslog("bind: %m");
		sleep(5 * retry);
		retry <<= 1;
	}
	if (retry == 0)
		return (-1);
	if (domain==AF_NS) {
		struct idp idp;
		if (setsockopt(s, 0, SO_HEADERS_ON_INPUT, &on, sizeof(on))) {
			syslog("setsockopt SEE HEADERS: %m");
			exit(1);
		}
		idp.idp_pt = NSPROTO_RI;
		if (setsockopt(s, 0, SO_DEFAULT_HEADERS, &idp, sizeof(idp))) {
			syslog("setsockopt SET HEADER: %m");
			exit(1);
		}
	}
	if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) {
		syslog("setsockopt SO_BROADCAST: %m");
		exit(1);
	}
	return (s);
}

/*
 * Fork and exit on EMT-- for profiling.
 */
fkexit()
{
	if (fork() == 0)
		exit(0);
}