/* $NetBSD: main.c,v 1.6 1995/12/10 10:07:05 mycroft Exp $ */ /* * 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. */ /* * 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" #ifdef __STDC__ #include #else #include #endif #include #ifdef SNMP #include "snmp.h" #endif #ifndef lint static char rcsid[] = "@(#) $Id: main.c,v 1.3 1995/12/19 17:48:04 deraadt Exp $"; #endif extern char *configfilename; char versionstring[100]; static char pidfilename[] = _PATH_MROUTED_PID; static char dumpfilename[] = _PATH_MROUTED_DUMP; static char cachefilename[] = _PATH_MROUTED_CACHE; static char genidfilename[] = _PATH_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 */ #ifdef SNMP #define NHANDLERS 34 #else #define NHANDLERS 2 #endif static struct ihandler { int fd; /* File descriptor */ ihfunc_t func; /* Function to call with &fd_set */ } ihandlers[NHANDLERS]; static int nhandlers = 0; /* * Forward declarations. */ static void fasttimer __P((int)); static void done __P((int)); static void dump __P((int)); static void fdump __P((int)); static void cdump __P((int)); static void restart __P((int)); static void timer __P((void)); static void cleanup __P((void)); static void resetlogging __P((void *)); /* To shut up gcc -Wstrict-prototypes */ int main __P((int argc, char **argv)); int register_input_handler(fd, func) int fd; ihfunc_t func; { if (nhandlers >= NHANDLERS) return -1; ihandlers[nhandlers].fd = fd; ihandlers[nhandlers++].func = func; return 0; } int main(argc, argv) int argc; char *argv[]; { register int recvlen; register int omask; int dummy; FILE *fp; struct timeval tv; u_int32_t prev_genid; int vers; fd_set rfds, readers; int nfds, n, i; #ifdef SNMP struct timeval timeout, *tvp = &timeout; struct timeval sched, *svp = &sched, now, *nvp = &now; int index, block; #endif 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; #ifdef SNMP } else if (strcmp(*argv, "-P") == 0) { if (argc > 1 && isdigit(*(argv + 1)[0])) { argv++, argc--; dest_port = atoi(*argv); } else dest_port = DEFAULT_PORT; #endif } 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); #ifdef SYSV (void)setpgrp(); #else #ifdef TIOCNOTTY t = open("/dev/tty", 2); if (t >= 0) { (void)ioctl(t, TIOCNOTTY, (char *)0); (void)close(t); } #else if (setsid() < 0) perror("setsid"); #endif #endif } 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 sprintf(versionstring, "mrouted version %d.%d", PROTOCOL_VERSION, MROUTED_VERSION); log(LOG_NOTICE, 0, "%s", versionstring); #ifdef SYSV srand48(time(NULL)); #else srandom(gethostid()); #endif /* * Get generation id */ gettimeofday(&tv, 0); 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(); init_routes(); init_ktable(); k_init_dvmrp(); /* enable DVMRP routing in kernel */ #ifndef OLD_KERNEL vers = k_get_version(); /*XXX * This function must change whenever the kernel version changes */ if ((((vers >> 8) & 0xff) != 3) || ((vers & 0xff) != 5)) log(LOG_ERR, 0, "kernel (v%d.%d)/mrouted (v%d.%d) version mismatch", (vers >> 8) & 0xff, vers & 0xff, PROTOCOL_VERSION, MROUTED_VERSION); #endif #ifdef SNMP if (i = snmp_init()) return i; gettimeofday(nvp, 0); if (nvp->tv_usec < 500000L){ svp->tv_usec = nvp->tv_usec + 500000L; svp->tv_sec = nvp->tv_sec; } else { svp->tv_usec = nvp->tv_usec - 500000L; svp->tv_sec = nvp->tv_sec + 1; } #endif /* SNMP */ init_vifs(); #ifdef RSRR rsrr_init(); #endif /* RSRR */ #if defined(__STDC__) || defined(__GNUC__) /* * Allow cleanup if unexpected exit. Apparently some architectures * have a kernel bug where closing the socket doesn't do an * ip_mrouter_done(), so we attempt to do it on exit. */ atexit(cleanup); #endif if (debug) fprintf(stderr, "pruning %s\n", pruning ? "on" : "off"); fp = fopen(pidfilename, "w"); if (fp != NULL) { fprintf(fp, "%d\n", (int)getpid()); (void) fclose(fp); } (void)signal(SIGALRM, fasttimer); (void)signal(SIGHUP, restart); (void)signal(SIGTERM, done); (void)signal(SIGINT, done); (void)signal(SIGUSR1, fdump); (void)signal(SIGUSR2, cdump); if (debug != 0) (void)signal(SIGQUIT, dump); FD_ZERO(&readers); FD_SET(igmp_socket, &readers); nfds = igmp_socket + 1; for (i = 0; i < nhandlers; i++) { FD_SET(ihandlers[i].fd, &readers); if (ihandlers[i].fd >= nfds) nfds = ihandlers[i].fd + 1; } /* * Install the vifs in the kernel as late as possible in the * initialization sequence. */ init_installvifs(); if (debug >= 2) dump(0); /* Start up the log rate-limiter */ resetlogging(NULL); (void)alarm(1); /* schedule first timer interrupt */ /* * Main receive loop. */ dummy = 0; for(;;) { #ifdef SYSV sigset_t block, oblock; #endif bcopy((char *)&readers, (char *)&rfds, sizeof(rfds)); #ifdef SNMP gettimeofday(nvp, 0); if (nvp->tv_sec > svp->tv_sec || (nvp->tv_sec == svp->tv_sec && nvp->tv_usec > svp->tv_usec)){ alarmTimer(nvp); eventTimer(nvp); if (nvp->tv_usec < 500000L){ svp->tv_usec = nvp->tv_usec + 500000L; svp->tv_sec = nvp->tv_sec; } else { svp->tv_usec = nvp->tv_usec - 500000L; svp->tv_sec = nvp->tv_sec + 1; } } tvp = &timeout; tvp->tv_sec = 0; tvp->tv_usec = 500000L; block = 0; snmp_select_info(&nfds, &rfds, tvp, &block); if (block == 1) tvp = NULL; /* block without timeout */ if ((n = select(nfds, &rfds, NULL, NULL, tvp)) < 0) #else if ((n = select(nfds, &rfds, NULL, NULL, NULL)) < 0) #endif { if (errno != EINTR) /* SIGALRM is expected */ log(LOG_WARNING, errno, "select failed"); continue; } if (FD_ISSET(igmp_socket, &rfds)) { recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE, 0, NULL, &dummy); if (recvlen < 0) { if (errno != EINTR) log(LOG_ERR, errno, "recvfrom"); continue; } #ifdef SYSV (void)sigemptyset(&block); (void)sigaddset(&block, SIGALRM); if (sigprocmask(SIG_BLOCK, &block, &oblock) < 0) log(LOG_ERR, errno, "sigprocmask"); #else omask = sigblock(sigmask(SIGALRM)); #endif accept_igmp(recvlen); #ifdef SYSV (void)sigprocmask(SIG_SETMASK, &oblock, (sigset_t *)NULL); #else (void)sigsetmask(omask); #endif } for (i = 0; i < nhandlers; i++) { if (FD_ISSET(ihandlers[i].fd, &rfds)) { (*ihandlers[i].func)(ihandlers[i].fd, &rfds); } } #ifdef SNMP snmp_read(&rfds); snmp_timeout(); /* poll */ #endif } } /* * routine invoked every second. Its 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(i) int i; { 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); } #ifdef SNMP sync_timer(); #endif /* * Advance virtual time */ virtual_time += TIMER_INTERVAL; } /* * On termination, let everyone know we're going away. */ static void done(i) int i; { log(LOG_NOTICE, 0, "%s exiting", versionstring); cleanup(); _exit(1); } static void cleanup() { static in_cleanup = 0; if (!in_cleanup) { in_cleanup++; #ifdef RSRR rsrr_clean(); #endif /* RSRR */ expire_all_routes(); report_to_all_neighbors(ALL_ROUTES); k_stop_dvmrp(); } } /* * Dump internal data structures to stderr. */ static void dump(i) int i; { dump_vifs(stderr); dump_routes(stderr); } /* * Dump internal data structures to a file. */ static void fdump(i) int i; { 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(i) int i; { FILE *fp; fp = fopen(cachefilename, "w"); if (fp != NULL) { dump_cache(fp); (void) fclose(fp); } } /* * Restart mrouted */ static void restart(i) int i; { register int omask; #ifdef SYSV sigset_t block, oblock; #endif log(LOG_NOTICE, 0, "%s restart", versionstring); /* * reset all the entries */ #ifdef SYSV (void)sigemptyset(&block); (void)sigaddset(&block, SIGALRM); if (sigprocmask(SIG_BLOCK, &block, &oblock) < 0) log(LOG_ERR, errno, "sigprocmask"); #else omask = sigblock(sigmask(SIGALRM)); #endif free_all_prunes(); free_all_routes(); stop_all_vifs(); k_stop_dvmrp(); close(igmp_socket); close(udp_socket); /* * start processing again */ dvmrp_genid++; pruning = 1; init_igmp(); init_routes(); init_ktable(); init_vifs(); k_init_dvmrp(); /* enable DVMRP routing in kernel */ init_installvifs(); #ifdef SYSV (void)sigprocmask(SIG_SETMASK, &oblock, (sigset_t *)NULL); #else (void)sigsetmask(omask); #endif } #define LOG_MAX_MSGS 20 /* if > 20/minute then shut up for a while */ #define LOG_SHUT_UP 600 /* shut up for 10 minutes */ static int log_nmsgs = 0; static void resetlogging(arg) void *arg; { int nxttime = 60; void *narg = NULL; if (arg == NULL && log_nmsgs > LOG_MAX_MSGS) { nxttime = LOG_SHUT_UP; narg = (void *)&log_nmsgs; /* just need some valid void * */ syslog(LOG_WARNING, "logging too fast, shutting up for %d minutes", LOG_SHUT_UP / 60); } else { log_nmsgs = 0; } timer_setTimer(nxttime, resetlogging, narg); } /* * 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. */ #ifdef __STDC__ void log(int severity, int syserr, char *format, ...) { va_list ap; static char fmt[211] = "warning - "; char *msg; char tbuf[20]; struct timeval now; struct tm *thyme; time_t t; va_start(ap, format); #else /*VARARGS3*/ void log(severity, syserr, format, va_alist) int severity, syserr; char *format; va_dcl { va_list ap; static char fmt[211] = "warning - "; char *msg; char tbuf[20]; struct timeval now; struct tm *thyme; time_t t; va_start(ap); #endif vsprintf(&fmt[10], format, ap); va_end(ap); msg = (severity == LOG_WARNING) ? fmt : &fmt[10]; switch (debug) { case 0: break; case 1: if (severity > LOG_NOTICE) break; case 2: if (severity > LOG_INFO ) break; default: gettimeofday(&now,NULL); t = now.tv_sec; thyme = localtime(&t); strftime(tbuf, sizeof(tbuf), "%X.%%03d ", thyme); fprintf(stderr, tbuf, now.tv_usec / 1000); fprintf(stderr, "%s", msg); 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) { if (log_nmsgs++ < LOG_MAX_MSGS) { if (syserr != 0) { errno = syserr; syslog(severity, "%s: %m", msg); } else syslog(severity, "%s", msg); } if (severity <= LOG_ERR) exit(-1); } } #ifdef DEBUG_MFC void md_log(what, origin, mcastgrp) int what; u_int32_t origin, mcastgrp; { static FILE *f = NULL; struct timeval tv; u_int32_t buf[4]; if (!f) { if ((f = fopen("/tmp/mrouted.clog", "w")) == NULL) { log(LOG_ERR, errno, "open /tmp/mrouted.clog"); } } gettimeofday(&tv, NULL); buf[0] = tv.tv_sec; buf[1] = what; buf[2] = origin; buf[3] = mcastgrp; fwrite(buf, sizeof(u_int32_t), 4, f); } #endif