1/*	$NetBSD: timed.c,v 1.30 2023/08/08 06:31:58 mrg Exp $	*/
2
3/*-
4 * Copyright (c) 1985, 1993 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#ifndef lint
34__COPYRIGHT("@(#) Copyright (c) 1985, 1993\
35 The Regents of the University of California.  All rights reserved.");
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)timed.c	8.2 (Berkeley) 3/26/95";
41#else
42__RCSID("$NetBSD: timed.c,v 1.30 2023/08/08 06:31:58 mrg Exp $");
43#endif
44#endif /* not lint */
45
46#define TSPTYPES
47#include "globals.h"
48#include <net/if.h>
49#include <sys/file.h>
50#include <sys/ioctl.h>
51#include <setjmp.h>
52#include "pathnames.h"
53#include <math.h>
54#include <sys/types.h>
55#include <sys/times.h>
56#include <util.h>
57#include <ifaddrs.h>
58#include <err.h>
59
60#ifdef HAVENIS
61#include <netgroup.h>
62#endif
63
64int trace = 0;
65int sock, sock_raw = -1;
66int status = 0;
67u_short sequence;			/* sequence number */
68long delay1;
69long delay2;
70
71int nslavenets;				/* nets where I could be a slave */
72int nmasternets;			/* nets where I could be a master */
73int nignorednets;			/* ignored nets */
74int nnets;				/* nets I am connected to */
75
76FILE *fd;				/* trace file FD */
77
78jmp_buf jmpenv;
79
80struct netinfo *nettab = 0;
81struct netinfo *slavenet;
82int Mflag;
83int justquit = 0;
84int debug;
85
86static struct nets {
87	char	 *name;
88	in_addr_t net;
89	struct nets *next;
90} *nets = 0;
91
92struct hosttbl hosttbl[NHOSTS+1];	/* known hosts */
93
94static struct goodhost {		/* hosts that we trust */
95	char	name[MAXHOSTNAMELEN+1];
96	struct goodhost *next;
97	char	perm;
98} *goodhosts;
99
100static char *goodgroup;			/* net group of trusted hosts */
101static void checkignorednets(void);
102static void pickslavenet(struct netinfo *);
103static void add_good_host(const char*,char);
104
105
106/*
107 * The timedaemons synchronize the clocks of hosts in a local area network.
108 * One daemon runs as master, all the others as slaves. The master
109 * performs the task of computing clock differences and sends correction
110 * values to the slaves.
111 * Slaves start an election to choose a new master when the latter disappears
112 * because of a machine crash, network partition, or when killed.
113 * A resolution protocol is used to kill all but one of the masters
114 * that happen to exist in segments of a partitioned network when the
115 * network partition is fixed.
116 *
117 * Authors: Riccardo Gusella & Stefano Zatti
118 */
119
120int
121main(int argc, char *argv[])
122{
123	int on;
124	int ret;
125	int nflag, iflag;
126	struct timeval ntime;
127	struct servent *srvp;
128	struct netinfo *ntp;
129	struct netinfo *ntip;
130	struct netinfo *savefromnet;
131	struct netent *nentp;
132	struct nets *nt;
133	struct sockaddr_in server;
134	uint16_t port;
135	int c;
136	extern char *optarg;
137	extern int optind, opterr;
138	struct ifaddrs *ifap, *ifa;
139
140#define	IN_MSG "-i and -n make no sense together\n"
141#ifdef HAVENIS
142#define USAGE "[-dtM] [-i net|-n net] [-F host1 host2 ...] [-G netgp]\n"
143#else
144#define USAGE "[-dtM] [-i net|-n net] [-F host1 host2 ...]\n"
145#endif /* HAVENIS */
146
147	ntip = NULL;
148
149	on = 1;
150	nflag = OFF;
151	iflag = OFF;
152
153	opterr = 0;
154	while ((c = getopt(argc, argv, "Mtdn:i:F:G:")) != -1) {
155		switch (c) {
156		case 'M':
157			Mflag = 1;
158			break;
159
160		case 't':
161			trace = 1;
162			break;
163
164		case 'n':
165			if (iflag)
166				errx(EXIT_FAILURE, "%s", IN_MSG);
167			nflag = ON;
168			addnetname(optarg);
169			break;
170
171		case 'i':
172			if (nflag)
173				errx(EXIT_FAILURE, "%s", IN_MSG);
174			iflag = ON;
175			addnetname(optarg);
176			break;
177
178		case 'F':
179			add_good_host(optarg,1);
180			while (optind < argc && argv[optind][0] != '-')
181				add_good_host(argv[optind++], 1);
182			break;
183
184		case 'd':
185			debug = 1;
186			break;
187		case 'G':
188			if (goodgroup != 0)
189				errx(EXIT_FAILURE, "timed: only one net group");
190			goodgroup = optarg;
191			break;
192		default:
193			errx(EXIT_FAILURE, "%s", USAGE);
194			break;
195		}
196	}
197	if (optind < argc)
198		errx(EXIT_FAILURE, "%s", USAGE);
199
200	/* If we care about which machine is the master, then we must
201	 *	be willing to be a master
202	 */
203	if (0 != goodgroup || 0 != goodhosts)
204		Mflag = 1;
205
206	if (gethostname(hostname, sizeof(hostname)) < 0)
207		err(EXIT_FAILURE, "gethostname");
208
209	hostname[sizeof(hostname) - 1] = '\0';
210	self.l_bak = &self;
211	self.l_fwd = &self;
212	self.h_bak = &self;
213	self.h_fwd = &self;
214	self.head = 1;
215	self.good = 1;
216
217	if (goodhosts != 0)		/* trust ourself */
218		add_good_host(hostname,1);
219
220	srvp = getservbyname("timed", "udp");
221	if (srvp == NULL)
222		errx(EXIT_FAILURE, "unknown service 'timed/udp'");
223
224	port = srvp->s_port;
225	(void)memset(&server, 0, sizeof(server));
226	server.sin_port = srvp->s_port;
227	server.sin_family = AF_INET;
228	sock = socket(AF_INET, SOCK_DGRAM, 0);
229	if (sock < 0)
230		err(EXIT_FAILURE, "socket");
231
232	if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on)) < 0)
233		err(EXIT_FAILURE, "setsockopt");
234
235	if (bind(sock, (struct sockaddr*)(void *)&server, sizeof(server))) {
236		if (errno == EADDRINUSE)
237			errx(EXIT_FAILURE, "time daemon already running");
238		else
239			err(EXIT_FAILURE, "bind");
240	}
241
242	/* initial seq number */
243	sequence = (u_short)arc4random_uniform(UINT16_MAX);
244
245	/* rounds kernel variable time to multiple of 5 ms. */
246	ntime.tv_sec = 0;
247	ntime.tv_usec = -((ntime.tv_usec/1000) % 5) * 1000;
248	(void)adjtime(&ntime, (struct timeval *)0);
249
250	for (nt = nets; nt; nt = nt->next) {
251		nentp = getnetbyname(nt->name);
252		if (nentp == 0) {
253			nt->net = inet_network(nt->name);
254			if (nt->net != INADDR_NONE)
255				nentp = getnetbyaddr(nt->net, AF_INET);
256		}
257		if (nentp != 0)
258			nt->net = nentp->n_net;
259		else if (nt->net == INADDR_NONE)
260			errx(EXIT_FAILURE, "unknown net %s", nt->name);
261		else if (nt->net == INADDR_ANY)
262			errx(EXIT_FAILURE, "bad net %s", nt->name);
263		else
264			warnx("warning: %s unknown in /etc/networks",
265				nt->name);
266
267		if (0 == (nt->net & 0xff000000))
268		    nt->net <<= 8;
269		if (0 == (nt->net & 0xff000000))
270		    nt->net <<= 8;
271		if (0 == (nt->net & 0xff000000))
272		    nt->net <<= 8;
273	}
274	if (getifaddrs(&ifap) != 0)
275		err(EXIT_FAILURE, "get interface configuration");
276
277	ntp = NULL;
278	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
279		if (ifa->ifa_addr->sa_family != AF_INET)
280			continue;
281		if (!ntp)
282			ntp = malloc(sizeof(struct netinfo));
283		(void)memset(ntp, 0, sizeof(*ntp));
284		ntp->my_addr=((struct sockaddr_in *)(void *)ifa->ifa_addr)->sin_addr;
285		ntp->status = NOMASTER;
286
287		if ((ifa->ifa_flags & IFF_UP) == 0)
288			continue;
289		if ((ifa->ifa_flags & IFF_BROADCAST) == 0 &&
290		    (ifa->ifa_flags & IFF_POINTOPOINT) == 0) {
291			continue;
292		}
293
294		ntp->mask = ((struct sockaddr_in *)(void *)
295		    ifa->ifa_netmask)->sin_addr.s_addr;
296
297		if (ifa->ifa_flags & IFF_BROADCAST) {
298			ntp->dest_addr = *(struct sockaddr_in *)(void *)ifa->ifa_broadaddr;
299			/* What if the broadcast address is all ones?
300			 * So we cannot just mask ntp->dest_addr.  */
301			ntp->net = ntp->my_addr;
302			ntp->net.s_addr &= ntp->mask;
303		} else {
304			ntp->dest_addr = *(struct sockaddr_in *)(void *)ifa->ifa_dstaddr;
305			ntp->net = ntp->dest_addr.sin_addr;
306		}
307
308		ntp->dest_addr.sin_port = port;
309
310		for (nt = nets; nt; nt = nt->next) {
311			if (ntohl(ntp->net.s_addr) == nt->net)
312				break;
313		}
314		if ((nflag && !nt) || (iflag && nt))
315			continue;
316
317		ntp->next = NULL;
318		if (nettab == NULL) {
319			nettab = ntp;
320		} else {
321			ntip->next = ntp;
322		}
323		ntip = ntp;
324		ntp = NULL;
325	}
326	freeifaddrs(ifap);
327	if (ntp)
328		(void) free(ntp);
329	if (nettab == NULL)
330		errx(EXIT_FAILURE, "no network usable");
331
332
333	/* microseconds to delay before responding to a broadcast */
334	delay1 = 1L + arc4random_uniform((100 * 1000L) - 1L);
335
336	/* election timer delay in secs. */
337	delay2 = MINTOUT + arc4random_uniform(MAXTOUT - MINTOUT);
338
339	if (!debug) {
340		daemon(debug, 0);
341		pidfile(NULL);
342	}
343
344	if (trace)
345		traceon();
346	openlog("timed", LOG_PID, LOG_DAEMON);
347
348	/*
349	 * keep returning here
350	 */
351	ret = setjmp(jmpenv);
352	savefromnet = fromnet;
353	setstatus();
354
355	if (Mflag) {
356		switch (ret) {
357
358		case 0:
359			checkignorednets();
360			pickslavenet(0);
361			break;
362		case 1:
363			/* Just lost our master */
364			if (slavenet != 0)
365				slavenet->status = election(slavenet);
366			if (!slavenet || slavenet->status == MASTER) {
367				checkignorednets();
368				pickslavenet(0);
369			} else {
370				makeslave(slavenet);	/* prune extras */
371			}
372			break;
373
374		case 2:
375			/* Just been told to quit */
376			justquit = 1;
377			pickslavenet(savefromnet);
378			break;
379		}
380
381		setstatus();
382		if (!(status & MASTER) && sock_raw != -1) {
383			/* sock_raw is not being used now */
384			(void)close(sock_raw);
385			sock_raw = -1;
386		}
387
388		if (status == MASTER)
389			master();
390		else
391			slave();
392
393	} else {
394		if (sock_raw != -1) {
395			(void)close(sock_raw);
396			sock_raw = -1;
397		}
398
399		if (ret) {
400			/* we just lost our master or were told to quit */
401			justquit = 1;
402		}
403		for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
404			if (ntp->status == MASTER) {
405				rmnetmachs(ntp);
406				ntp->status = NOMASTER;
407			}
408		}
409		checkignorednets();
410		pickslavenet(0);
411		setstatus();
412
413		slave();
414	}
415	/* NOTREACHED */
416	return(0);
417}
418
419
420/* suppress an upstart, untrustworthy, self-appointed master
421 */
422void
423suppress(struct sockaddr_in *addr, char *name, struct netinfo *net)
424{
425	struct sockaddr_in tgt;
426	char tname[MAXHOSTNAMELEN];
427	struct tsp msg;
428	static struct timeval wait;
429
430	if (trace)
431		fprintf(fd, "suppress: %s\n", name);
432	tgt = *addr;
433	(void)strlcpy(tname, name, sizeof(tname));
434
435	while (0 != readmsg(TSP_ANY, ANYADDR, &wait, net)) {
436		if (trace)
437			fprintf(fd, "suppress:\tdiscarded packet from %s\n",
438				    name);
439	}
440
441	syslog(LOG_NOTICE, "suppressing false master %s", tname);
442	msg.tsp_type = TSP_QUIT;
443	set_tsp_name(&msg, hostname);
444	(void)acksend(&msg, &tgt, tname, TSP_ACK, 0, 1);
445}
446
447void
448lookformaster(struct netinfo *ntp)
449{
450	struct tsp resp, conflict, *answer;
451	struct timeval ntime;
452	char mastername[MAXHOSTNAMELEN];
453	struct sockaddr_in masteraddr;
454
455	get_goodgroup(0);
456	ntp->status = SLAVE;
457
458	/* look for master */
459	resp.tsp_type = TSP_MASTERREQ;
460	set_tsp_name(&resp, hostname);
461	answer = acksend(&resp, &ntp->dest_addr, ANYADDR,
462			 TSP_MASTERACK, ntp, 0);
463	if (answer != 0 && !good_host_name(answer->tsp_name)) {
464		suppress(&from, answer->tsp_name, ntp);
465		ntp->status = NOMASTER;
466		answer = 0;
467	}
468	if (answer == 0) {
469		/*
470		 * Various conditions can cause conflict: races between
471		 * two just started timedaemons when no master is
472		 * present, or timedaemons started during an election.
473		 * A conservative approach is taken.  Give up and become a
474		 * slave, postponing election of a master until first
475		 * timer expires.
476		 */
477		ntime.tv_sec = ntime.tv_usec = 0;
478		answer = readmsg(TSP_MASTERREQ, ANYADDR, &ntime, ntp);
479		if (answer != 0) {
480			if (!good_host_name(answer->tsp_name)) {
481				suppress(&from, answer->tsp_name, ntp);
482				ntp->status = NOMASTER;
483			}
484			return;
485		}
486
487		ntime.tv_sec = ntime.tv_usec = 0;
488		answer = readmsg(TSP_MASTERUP, ANYADDR, &ntime, ntp);
489		if (answer != 0) {
490			if (!good_host_name(answer->tsp_name)) {
491				suppress(&from, answer->tsp_name, ntp);
492				ntp->status = NOMASTER;
493			}
494			return;
495		}
496
497		ntime.tv_sec = ntime.tv_usec = 0;
498		answer = readmsg(TSP_ELECTION, ANYADDR, &ntime, ntp);
499		if (answer != 0) {
500			if (!good_host_name(answer->tsp_name)) {
501				suppress(&from, answer->tsp_name, ntp);
502				ntp->status = NOMASTER;
503			}
504			return;
505		}
506
507		if (Mflag)
508			ntp->status = MASTER;
509		else
510			ntp->status = NOMASTER;
511		return;
512	}
513
514	ntp->status = SLAVE;
515	get_tsp_name(answer, mastername, sizeof(mastername));
516	masteraddr = from;
517
518	/*
519	 * If network has been partitioned, there might be other
520	 * masters; tell the one we have just acknowledged that
521	 * it has to gain control over the others.
522	 */
523	ntime.tv_sec = 0;
524	ntime.tv_usec = 300000;
525	answer = readmsg(TSP_MASTERACK, ANYADDR, &ntime, ntp);
526	/*
527	 * checking also not to send CONFLICT to ack'ed master
528	 * due to duplicated MASTERACKs
529	 */
530	if (answer != NULL &&
531	    strcmp(answer->tsp_name, mastername) != 0) {
532		conflict.tsp_type = TSP_CONFLICT;
533		set_tsp_name(&conflict, hostname);
534		if (!acksend(&conflict, &masteraddr, mastername,
535			     TSP_ACK, 0, 0)) {
536			syslog(LOG_ERR,
537			       "error on sending TSP_CONFLICT");
538		}
539	}
540}
541
542/*
543 * based on the current network configuration, set the status, and count
544 * networks;
545 */
546void
547setstatus(void)
548{
549	struct netinfo *ntp;
550
551	status = 0;
552	nmasternets = nslavenets = nnets = nignorednets = 0;
553	if (trace)
554		fprintf(fd, "Net status:\n");
555	for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
556		switch ((int)ntp->status) {
557		case MASTER:
558			nmasternets++;
559			break;
560		case SLAVE:
561			nslavenets++;
562			break;
563		case NOMASTER:
564		case IGNORE:
565			nignorednets++;
566			break;
567		}
568		if (trace) {
569			fprintf(fd, "\t%-16s", inet_ntoa(ntp->net));
570			switch ((int)ntp->status) {
571			case NOMASTER:
572				fprintf(fd, "NOMASTER\n");
573				break;
574			case MASTER:
575				fprintf(fd, "MASTER\n");
576				break;
577			case SLAVE:
578				fprintf(fd, "SLAVE\n");
579				break;
580			case IGNORE:
581				fprintf(fd, "IGNORE\n");
582				break;
583			default:
584				fprintf(fd, "invalid state %d\n",
585					(int)ntp->status);
586				break;
587			}
588		}
589		nnets++;
590		status |= ntp->status;
591	}
592	status &= ~IGNORE;
593	if (trace)
594		fprintf(fd,
595		    "\tnets=%d masters=%d slaves=%d ignored=%d delay2=%ld\n",
596		    nnets, nmasternets, nslavenets, nignorednets, (long)delay2);
597}
598
599void
600makeslave(struct netinfo *net)
601{
602	struct netinfo *ntp;
603
604	for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
605		if (ntp->status == SLAVE && ntp != net)
606			ntp->status = IGNORE;
607	}
608	slavenet = net;
609}
610
611/*
612 * Try to become master over ignored nets..
613 */
614static void
615checkignorednets(void)
616{
617	struct netinfo *ntp;
618
619	for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
620		if (!Mflag && ntp->status == SLAVE)
621			break;
622
623		if (ntp->status == IGNORE || ntp->status == NOMASTER) {
624			lookformaster(ntp);
625			if (!Mflag && ntp->status == SLAVE)
626				break;
627		}
628	}
629}
630
631/*
632 * choose a good network on which to be a slave
633 *	The ignored networks must have already been checked.
634 *	Take a hint about for a good network.
635 */
636static void
637pickslavenet(struct netinfo *ntp)
638{
639	if (slavenet != 0 && slavenet->status == SLAVE) {
640		makeslave(slavenet);		/* prune extras */
641		return;
642	}
643
644	if (ntp == 0 || ntp->status != SLAVE) {
645		for (ntp = nettab; ntp != 0; ntp = ntp->next) {
646			if (ntp->status == SLAVE)
647				break;
648		}
649	}
650	makeslave(ntp);
651}
652
653char *
654date(void)
655{
656	struct	timeval tv;
657	time_t t;
658
659	(void)gettimeofday(&tv, (struct timezone *)0);
660	t = tv.tv_sec;
661	return (ctime(&t));
662}
663
664void
665addnetname(char *name)
666{
667	struct nets **netlist = &nets;
668
669	while (*netlist)
670		netlist = &((*netlist)->next);
671	*netlist = calloc(1, sizeof **netlist);
672	if (*netlist == NULL)
673		err(EXIT_FAILURE, "malloc failed");
674	(*netlist)->name = name;
675}
676
677/* note a host as trustworthy */
678static void
679add_good_host(const char* name,
680	      char perm)		/* 1=not part of the netgroup */
681{
682	struct goodhost *ghp;
683	struct hostent *hentp;
684
685	ghp = calloc(1, sizeof(*ghp));
686	if (!ghp) {
687		syslog(LOG_ERR, "malloc failed");
688		exit(EXIT_FAILURE);
689	}
690
691	(void)strncpy(&ghp->name[0], name, sizeof(ghp->name) - 1);
692	ghp->name[sizeof(ghp->name) - 1] = 0;
693	ghp->next = goodhosts;
694	ghp->perm = perm;
695	goodhosts = ghp;
696
697	hentp = gethostbyname(name);
698	if (NULL == hentp && perm)
699		warnx("unknown host %s", name);
700}
701
702
703/* update our image of the net-group of trustworthy hosts
704 */
705void
706get_goodgroup(int force)
707{
708# define NG_DELAY (30*60*CLK_TCK)	/* 30 minutes */
709	static unsigned long last_update;
710	static int firsttime;
711	unsigned long new_update;
712	struct goodhost *ghp, **ghpp;
713#ifdef HAVENIS
714	struct hosttbl *htp;
715	const char *mach, *usr, *dom;
716#endif
717	struct tms tm;
718
719	if (firsttime == 0) {
720		last_update = -NG_DELAY;
721		firsttime++;
722	}
723
724	/* if no netgroup, then we are finished */
725	if (goodgroup == 0 || !Mflag)
726		return;
727
728	/* Do not chatter with the netgroup master too often.
729	 */
730	new_update = times(&tm);
731	if (new_update < last_update + NG_DELAY
732	    && !force)
733		return;
734	last_update = new_update;
735
736	/* forget the old temporary entries */
737	ghpp = &goodhosts;
738	while (0 != (ghp = *ghpp)) {
739		if (!ghp->perm) {
740			*ghpp = ghp->next;
741			free(ghp);
742		} else {
743			ghpp = &ghp->next;
744		}
745	}
746
747#ifdef HAVENIS
748	/* quit now if we are not one of the trusted masters
749	 */
750	if (!innetgr(goodgroup, &hostname[0], 0,0)) {
751		if (trace)
752			(void)fprintf(fd, "get_goodgroup: %s not in %s\n",
753				      &hostname[0], goodgroup);
754		return;
755	}
756	if (trace)
757		(void)fprintf(fd, "get_goodgroup: %s in %s\n",
758				  &hostname[0], goodgroup);
759
760	/* mark the entire netgroup as trusted */
761	(void)setnetgrent(goodgroup);
762	while (getnetgrent(&mach,&usr,&dom)) {
763		if (0 != mach)
764			add_good_host(mach,0);
765	}
766	(void)endnetgrent();
767
768	/* update list of slaves */
769	for (htp = self.l_fwd; htp != &self; htp = htp->l_fwd) {
770		htp->good = good_host_name(&htp->name[0]);
771	}
772#endif /* HAVENIS */
773}
774
775
776/* see if a machine is trustworthy
777 */
778int					/* 1=trust hp to change our date */
779good_host_name(char *name)
780{
781	struct goodhost *ghp = goodhosts;
782	char c;
783
784	if (!ghp || !Mflag)		/* trust everyone if no one named */
785		return 1;
786
787	c = *name;
788	do {
789		if (c == ghp->name[0]
790		    && !strcasecmp(name, ghp->name))
791			return 1;	/* found him, so say so */
792	} while (0 != (ghp = ghp->next));
793
794	if (!strcasecmp(name,hostname))	/* trust ourself */
795		return 1;
796
797	return 0;			/* did not find him */
798}
799