mrouted from multicast 3.3 distribution

1 files changed, 439 insertions, 0 deletions

diff --git a/usr.sbin/mrouted/main.c b/usr.sbin/mrouted/main.c
new file mode 100644
index 0000000..22a0214
--- /dev/null
+++ b/usr.sbin/mrouted/main.c
@@ -0,0 +1,439 @@
+/*
+ * The mrouted program is covered by the license in the accompanying file
+ * named "LICENSE".  Use of the mrouted program represents acceptance of
+ * the terms and conditions listed in that file.
+ *
+ * The mrouted program is COPYRIGHT 1989 by The Board of Trustees of
+ * Leland Stanford Junior University.
+ *
+ *
+ * $Id: main.c,v 1.8 1994/08/24 23:53:42 thyagara Exp $
+ */
+
+/*
+ * Written by Steve Deering, Stanford University, February 1989.
+ *
+ * (An earlier version of DVMRP was implemented by David Waitzman of
+ *  BBN STC by extending Berkeley's routed program.  Some of Waitzman's
+ *  extensions have been incorporated into mrouted, but none of the
+ *  original routed code has been adopted.)
+ */
+
+
+#include "defs.h"
+
+extern char *configfilename;
+
+static char pidfilename[]  = "/etc/mrouted.pid";
+static char dumpfilename[] = "/usr/tmp/mrouted.dump";
+static char cachefilename[] = "/usr/tmp/mrouted.cache";
+static char genidfilename[] = "/usr/tmp/mrouted.genid";
+
+int cache_lifetime 	= DEFAULT_CACHE_LIFETIME;
+int max_prune_lifetime 	= DEFAULT_CACHE_LIFETIME * 2;
+
+int debug = 0;
+u_char pruning = 1;	/* Enable pruning by default */
+
+
+/*
+ * Forward declarations.
+ */
+static void fasttimer();
+static void timer();
+static void hup();
+static void dump();
+static void fdump();
+static void cdump();
+static void restart();
+
+main(argc, argv)
+    int argc;
+    char *argv[];
+{
+    register int recvlen;
+    register int omask;
+    int dummy;
+    FILE *fp;
+    extern uid_t geteuid();
+    struct timeval tv;
+    struct timezone tzp;
+    u_long prev_genid;
+
+    setlinebuf(stderr);
+
+    if (geteuid() != 0) {
+	fprintf(stderr, "must be root\n");
+	exit(1);
+    }
+
+    argv++, argc--;
+    while (argc > 0 && *argv[0] == '-') {
+	if (strcmp(*argv, "-d") == 0) {
+	    if (argc > 1 && isdigit(*(argv + 1)[0])) {
+		argv++, argc--;
+		debug = atoi(*argv);
+	    } else
+		debug = DEFAULT_DEBUG;
+	} else if (strcmp(*argv, "-c") == 0) {
+	    if (argc > 1) {
+		argv++, argc--;
+		configfilename = *argv;
+	    } else
+		goto usage;
+	} else if (strcmp(*argv, "-p") == 0) {
+	    pruning = 0;
+	} else
+	    goto usage;
+	argv++, argc--;
+    }
+
+    if (argc > 0) {
+usage:	fprintf(stderr, 
+		"usage: mrouted [-p] [-c configfile] [-d [debug_level]]\n");
+	exit(1);
+    }
+
+    if (debug == 0) {
+	/*
+	 * Detach from the terminal
+	 */
+	int t;
+
+	if (fork()) exit(0);
+	(void)close(0);
+	(void)close(1);
+	(void)close(2);
+	(void)open("/", 0);
+	(void)dup2(0, 1);
+	(void)dup2(0, 2);
+	t = open("/dev/tty", 2);
+	if (t >= 0) {
+	    (void)ioctl(t, TIOCNOTTY, (char *)0);
+	    (void)close(t);
+	}
+    }
+    else
+	fprintf(stderr, "debug level %u\n", debug);
+
+#ifdef LOG_DAEMON
+    (void)openlog("mrouted", LOG_PID, LOG_DAEMON);
+    (void)setlogmask(LOG_UPTO(LOG_NOTICE));
+#else
+    (void)openlog("mrouted", LOG_PID);
+#endif
+    log(LOG_NOTICE, 0, "mrouted version %d.%d",
+			PROTOCOL_VERSION, MROUTED_VERSION);
+
+    srandom(gethostid());
+
+    /*
+     * Get generation id 
+     */
+    gettimeofday(&tv, &tzp);
+    dvmrp_genid = tv.tv_sec;
+
+    fp = fopen(genidfilename, "r");
+    if (fp != NULL) {
+	fscanf(fp, "%d", &prev_genid);
+	if (prev_genid == dvmrp_genid)
+	    dvmrp_genid++;
+	(void) fclose(fp);
+    }
+
+    fp = fopen(genidfilename, "w");
+    if (fp != NULL) {
+	fprintf(fp, "%d", dvmrp_genid);
+	(void) fclose(fp);
+    }
+
+    callout_init();
+    init_igmp();
+    k_init_dvmrp();		/* enable DVMRP routing in kernel */
+    init_routes();
+    init_ktable();
+    init_vifs();
+
+    if (debug)
+	fprintf(stderr, "pruning %s\n", pruning ? "on" : "off");
+
+    fp = fopen(pidfilename, "w");		
+    if (fp != NULL) {
+	fprintf(fp, "%d\n", getpid());
+	(void) fclose(fp);
+    }
+
+    if (debug >= 2) dump();
+
+    (void)signal(SIGALRM, fasttimer);
+
+    (void)signal(SIGHUP,  restart);
+    (void)signal(SIGTERM, hup);
+    (void)signal(SIGINT,  hup);
+    (void)signal(SIGUSR1, fdump);
+    (void)signal(SIGUSR2, cdump);
+    if (debug != 0)
+	(void)signal(SIGQUIT, dump);
+
+    (void)alarm(1);	 /* schedule first timer interrupt */
+
+    /*
+     * Main receive loop.
+     */
+    dummy = 0;
+    for(;;) {
+	recvlen = recvfrom(igmp_socket, recv_buf, sizeof(recv_buf),
+			   0, NULL, &dummy);
+	if (recvlen < 0) {	
+	    if (errno != EINTR) log(LOG_ERR, errno, "recvfrom");
+	    continue;
+	}
+	omask = sigblock(sigmask(SIGALRM));
+	accept_igmp(recvlen);
+	(void)sigsetmask(omask);
+    }
+}
+
+
+/*
+ * routine invoked every second.  It's main goal is to cycle through
+ * the routing table and send partial updates to all neighbors at a
+ * rate that will cause the entire table to be sent in ROUTE_REPORT_INTERVAL
+ * seconds.  Also, every TIMER_INTERVAL seconds it calls timer() to
+ * do all the other time-based processing.
+ */
+static void fasttimer()
+{
+    static unsigned int tlast;
+    static unsigned int nsent;
+    register unsigned int t = tlast + 1;
+    register int n;
+
+    /*
+     * if we're in the last second, send everything that's left.
+     * otherwise send at least the fraction we should have sent by now.
+     */
+    if (t >= ROUTE_REPORT_INTERVAL) {
+	register int nleft = nroutes - nsent;
+	while (nleft > 0) {
+	    if ((n = report_next_chunk()) <= 0)
+		break;
+	    nleft -= n;
+	}
+	tlast = 0;
+	nsent = 0;
+    } else {
+	register unsigned int ncum = nroutes * t / ROUTE_REPORT_INTERVAL;
+	while (nsent < ncum) {
+	    if ((n = report_next_chunk()) <= 0)
+		break;
+	    nsent += n;
+	}
+	tlast = t;
+    }
+    if ((t % TIMER_INTERVAL) == 0)
+	timer();
+
+    age_callout_queue();/* Advance the timer for the callout queue
+				for groups */	
+    alarm(1);
+}
+
+/*
+ * The 'virtual_time' variable is initialized to a value that will cause the
+ * first invocation of timer() to send a probe or route report to all vifs
+ * and send group membership queries to all subnets for which this router is
+ * querier.  This first invocation occurs approximately TIMER_INTERVAL seconds
+ * after the router starts up.   Note that probes for neighbors and queries
+ * for group memberships are also sent at start-up time, as part of initial-
+ * ization.  This repetition after a short interval is desirable for quickly
+ * building up topology and membership information in the presence of possible
+ * packet loss.
+ *
+ * 'virtual_time' advances at a rate that is only a crude approximation of
+ * real time, because it does not take into account any time spent processing,
+ * and because the timer intervals are sometimes shrunk by a random amount to
+ * avoid unwanted synchronization with other routers.
+ */
+
+static u_long virtual_time = 0;
+
+
+/*
+ * Timer routine.  Performs periodic neighbor probing, route reporting, and
+ * group querying duties, and drives various timers in routing entries and
+ * virtual interface data structures.
+ */
+static void timer()
+{
+    age_routes();	/* Advance the timers in the route entries     */
+    age_vifs();		/* Advance the timers for neighbors */
+    age_table_entry();	/* Advance the timers for the cache entries */
+
+    if (virtual_time % GROUP_QUERY_INTERVAL == 0) {
+	/*
+	 * Time to query the local group memberships on all subnets
+	 * for which this router is the elected querier.
+	 */
+	query_groups();
+    }
+
+    if (virtual_time % NEIGHBOR_PROBE_INTERVAL == 0) {
+	/*
+	 * Time to send a probe on all vifs from which no neighbors have
+	 * been heard.  Also, check if any inoperative interfaces have now
+	 * come up.  (If they have, they will also be probed as part of
+	 * their initialization.)
+	 */
+	probe_for_neighbors();
+
+	if (vifs_down)
+	    check_vif_state();
+    }
+
+    delay_change_reports = FALSE;
+    if (routes_changed) {
+	/*
+	 * Some routes have changed since the last timer interrupt, but
+	 * have not been reported yet.  Report the changed routes to all
+	 * neighbors.
+	 */
+	report_to_all_neighbors(CHANGED_ROUTES);
+    }
+
+    /*
+     * Advance virtual time
+     */
+    virtual_time += TIMER_INTERVAL;
+}
+
+
+/*
+ * On hangup signal, let everyone know we're going away.
+ */
+static void hup()
+{
+    log(LOG_INFO, 0, "hup");
+    expire_all_routes();
+    report_to_all_neighbors(ALL_ROUTES);
+    exit(1);
+}
+
+
+/*
+ * Dump internal data structures to stderr.
+ */
+static void dump()
+{
+    dump_vifs(stderr);
+    dump_routes(stderr);
+}
+
+
+/*
+ * Dump internal data structures to a file.
+ */
+static void fdump()
+{
+    FILE *fp;
+
+    fp = fopen(dumpfilename, "w");
+    if (fp != NULL) {
+	dump_vifs(fp);
+	dump_routes(fp);
+	(void) fclose(fp);
+    }
+}
+
+
+/*
+ * Dump local cache contents to a file.
+ */
+static void cdump()
+{
+    FILE *fp;
+
+    fp = fopen(cachefilename, "w");
+    if (fp != NULL) {
+	dump_cache(fp); 
+	(void) fclose(fp);
+    }
+}
+
+
+/*
+ * Restart mrouted
+ */
+static void restart()
+{
+    register int omask;
+
+    log(LOG_INFO, 0, "restart");
+
+    /*
+     * reset all the entries
+     */
+    omask = sigblock(sigmask(SIGALRM));
+    free_all_prunes();
+    free_all_routes();
+    stop_all_vifs();
+    k_stop_dvmrp();
+
+    /*
+     * start processing again
+     */
+    dvmrp_genid++;
+    pruning = 1;
+
+    init_igmp();
+    k_init_dvmrp();		/* enable DVMRP routing in kernel */
+    init_routes();
+    init_ktable();
+    init_vifs();
+
+    (void)sigsetmask(omask);
+}
+
+
+/*
+ * Log errors and other messages to the system log daemon and to stderr,
+ * according to the severity of the message and the current debug level.
+ * For errors of severity LOG_ERR or worse, terminate the program.
+ */
+void log(severity, syserr, format, a, b, c, d, e)
+    int severity, syserr;
+    char *format;
+    int a, b, c, d, e;
+{
+    char fmt[100];
+
+    switch (debug) {
+	case 0: break;
+	case 1: if (severity > LOG_NOTICE) break;
+	case 2: if (severity > LOG_INFO  ) break;
+	default:
+	    fmt[0] = '\0';
+	    if (severity == LOG_WARNING) strcat(fmt, "warning - ");
+	    strncat(fmt, format, 80);
+	    fprintf(stderr, fmt, a, b, c, d, e);
+	    if (syserr == 0)
+		fprintf(stderr, "\n");
+	    else if(syserr < sys_nerr)
+		fprintf(stderr, ": %s\n", sys_errlist[syserr]);
+	    else
+		fprintf(stderr, ": errno %d\n", syserr);
+    }
+
+    if (severity <= LOG_NOTICE) {
+	fmt[0] = '\0';
+	if (severity == LOG_WARNING) strcat(fmt, "warning - ");
+	strncat(fmt, format, 80);
+	if (syserr != 0) {
+		strcat(fmt, ": %m");
+		errno = syserr;
+	}
+	syslog(severity, fmt, a, b, c, d, e);
+
+	if (severity <= LOG_ERR) exit(-1);
+    }
+}