1/*
2 * ntpd.c - main program for the fixed point NTP daemon
3 */
4
5#ifdef HAVE_CONFIG_H
6# include <config.h>
7#endif
8
9#include "ntp_machine.h"
10#include "ntpd.h"
11#include "ntp_io.h"
12#include "ntp_stdlib.h"
13#include <ntp_random.h>
14
15#include "ntp_config.h"
16#include "ntp_syslog.h"
17#include "ntp_assert.h"
18#include "isc/error.h"
19#include "isc/strerror.h"
20#include "isc/formatcheck.h"
21#include "iosignal.h"
22
23#ifdef SIM
24# include "ntpsim.h"
25#endif
26
27#include "ntp_libopts.h"
28#include "ntpd-opts.h"
29
30/* there's a short treatise below what the thread stuff is for.
31 * [Bug 2954] enable the threading warm-up only for Linux.
32 */
33#if defined(HAVE_PTHREADS) && HAVE_PTHREADS && !defined(NO_THREADS)
34# ifdef HAVE_PTHREAD_H
35#  include <pthread.h>
36# endif
37# if defined(linux)
38#  define NEED_PTHREAD_WARMUP
39# endif
40#endif
41
42#ifdef HAVE_UNISTD_H
43# include <unistd.h>
44#endif
45#ifdef HAVE_SYS_STAT_H
46# include <sys/stat.h>
47#endif
48#ifdef HAVE_SYS_WAIT_H
49# include <sys/wait.h>
50#endif
51#include <stdio.h>
52#ifdef HAVE_SYS_PARAM_H
53# include <sys/param.h>
54#endif
55#ifdef HAVE_SYS_SIGNAL_H
56# include <sys/signal.h>
57#else
58# include <signal.h>
59#endif
60#ifdef HAVE_SYS_IOCTL_H
61# include <sys/ioctl.h>
62#endif /* HAVE_SYS_IOCTL_H */
63#if defined(HAVE_RTPRIO)
64# ifdef HAVE_SYS_LOCK_H
65#  include <sys/lock.h>
66# endif
67# include <sys/rtprio.h>
68#else
69# ifdef HAVE_PLOCK
70#  ifdef HAVE_SYS_LOCK_H
71#	include <sys/lock.h>
72#  endif
73# endif
74#endif
75#if defined(HAVE_SCHED_SETSCHEDULER)
76# ifdef HAVE_SCHED_H
77#  include <sched.h>
78# else
79#  ifdef HAVE_SYS_SCHED_H
80#   include <sys/sched.h>
81#  endif
82# endif
83#endif
84#if defined(HAVE_SYS_MMAN_H)
85# include <sys/mman.h>
86#endif
87
88#ifdef HAVE_SYSEXITS_H
89# include <sysexits.h>
90#endif
91
92#ifdef HAVE_TERMIOS_H
93# include <termios.h>
94#endif
95
96#ifdef SYS_DOMAINOS
97# include <apollo/base.h>
98#endif /* SYS_DOMAINOS */
99
100
101#include "recvbuff.h"
102#include "ntp_cmdargs.h"
103
104#if 0				/* HMS: I don't think we need this. 961223 */
105#ifdef LOCK_PROCESS
106# ifdef SYS_SOLARIS
107#  include <sys/mman.h>
108# else
109#  include <sys/lock.h>
110# endif
111#endif
112#endif
113
114#ifdef SYS_WINNT
115# include "ntservice.h"
116#endif
117
118#ifdef _AIX
119# include <ulimit.h>
120#endif /* _AIX */
121
122#ifdef SCO5_CLOCK
123# include <sys/ci/ciioctl.h>
124#endif
125
126#ifdef HAVE_DROPROOT
127# include <ctype.h>
128# include <grp.h>
129# include <pwd.h>
130#ifdef HAVE_LINUX_CAPABILITIES
131# include <sys/capability.h>
132# include <sys/prctl.h>
133#endif /* HAVE_LINUX_CAPABILITIES */
134#if defined(HAVE_PRIV_H) && defined(HAVE_SOLARIS_PRIVS)
135# include <priv.h>
136#endif /* HAVE_PRIV_H */
137#endif /* HAVE_DROPROOT */
138
139#if defined (LIBSECCOMP) && (KERN_SECCOMP)
140/* # include <sys/types.h> */
141# include <sys/resource.h>
142# include <seccomp.h>
143#endif /* LIBSECCOMP and KERN_SECCOMP */
144
145#ifdef HAVE_DNSREGISTRATION
146# include <dns_sd.h>
147DNSServiceRef mdns;
148#endif
149
150/* In case 'sysexits.h' is unavailable, define some exit codes here: */
151#ifndef EX_SOFTWARE
152# define EX_SOFTWARE	70
153#endif
154#ifndef EX_OSERR
155# define EX_OSERR	71
156#endif
157#ifndef EX_IOERR
158# define EX_IOERR	74
159#endif
160#ifndef EX_PROTOCOL
161#define EX_PROTOCOL	76
162#endif
163
164
165#ifdef HAVE_SETPGRP_0
166# define ntp_setpgrp(x, y)	setpgrp()
167#else
168# define ntp_setpgrp(x, y)	setpgrp(x, y)
169#endif
170
171#ifdef HAVE_SOLARIS_PRIVS
172# define LOWPRIVS "basic,sys_time,net_privaddr,proc_setid,!proc_info,!proc_session,!proc_exec"
173static priv_set_t *lowprivs = NULL;
174static priv_set_t *highprivs = NULL;
175#endif /* HAVE_SOLARIS_PRIVS */
176/*
177 * Scheduling priority we run at
178 */
179#define NTPD_PRIO	(-12)
180
181int priority_done = 2;		/* 0 - Set priority */
182				/* 1 - priority is OK where it is */
183				/* 2 - Don't set priority */
184				/* 1 and 2 are pretty much the same */
185
186int listen_to_virtual_ips = TRUE;
187
188/*
189 * No-fork flag.  If set, we do not become a background daemon.
190 */
191int nofork;			/* Fork by default */
192
193#ifdef HAVE_DNSREGISTRATION
194/*
195 * mDNS registration flag. If set, we attempt to register with the mDNS system, but only
196 * after we have synched the first time. If the attempt fails, then try again once per
197 * minute for up to 5 times. After all, we may be starting before mDNS.
198 */
199int mdnsreg = FALSE;
200int mdnstries = 5;
201#endif  /* HAVE_DNSREGISTRATION */
202
203#ifdef HAVE_LINUX_CAPABILITIES
204int have_caps;		/* runtime check whether capabilities work */
205#endif /* HAVE_LINUX_CAPABILITIES */
206
207#ifdef HAVE_DROPROOT
208int droproot;
209int root_dropped;
210char *user;		/* User to switch to */
211char *group;		/* group to switch to */
212const char *chrootdir;	/* directory to chroot to */
213uid_t sw_uid;
214gid_t sw_gid;
215struct group *gr;
216struct passwd *pw;
217#endif /* HAVE_DROPROOT */
218
219#ifdef HAVE_WORKING_FORK
220int	daemon_pipe[2] = { -1, -1 };
221#endif
222
223/*
224 * Version declaration
225 */
226extern const char *Version;
227
228char const *progname;
229
230int was_alarmed;
231
232#ifdef DECL_SYSCALL
233/*
234 * We put this here, since the argument profile is syscall-specific
235 */
236extern int syscall	(int, ...);
237#endif /* DECL_SYSCALL */
238
239
240#if !defined(SIM) && defined(SIGDIE1)
241static volatile int signalled	= 0;
242static volatile int signo	= 0;
243
244/* In an ideal world, 'finish_safe()' would declared as noreturn... */
245static	void		finish_safe	(int);
246static	RETSIGTYPE	finish		(int);
247#endif
248
249#if !defined(SIM) && defined(HAVE_WORKING_FORK)
250static int	wait_child_sync_if	(int, unsigned long);
251static int	wait_child_exit_if	(pid_t, int);
252#endif
253
254#if !defined(SIM) && !defined(SYS_WINNT)
255# ifdef	DEBUG
256static	RETSIGTYPE	moredebug	(int);
257static	RETSIGTYPE	lessdebug	(int);
258# else	/* !DEBUG follows */
259static	RETSIGTYPE	no_debug	(int);
260# endif	/* !DEBUG */
261#endif	/* !SIM && !SYS_WINNT */
262
263#ifndef WORK_FORK
264int	saved_argc;
265char **	saved_argv;
266#endif
267
268#ifndef SIM
269int		ntpdmain		(int, char **);
270static void	set_process_priority	(void);
271static void	assertion_failed	(const char *, int,
272					 isc_assertiontype_t,
273					 const char *)
274			__attribute__	((__noreturn__));
275static void	library_fatal_error	(const char *, int,
276					 const char *, va_list)
277					ISC_FORMAT_PRINTF(3, 0);
278static void	library_unexpected_error(const char *, int,
279					 const char *, va_list)
280					ISC_FORMAT_PRINTF(3, 0);
281#endif	/* !SIM */
282
283
284/* Bug2332 unearthed a problem in the interaction of reduced user
285 * privileges, the limits on memory usage and some versions of the
286 * pthread library on Linux systems. The 'pthread_cancel()' function and
287 * likely some others need to track the stack of the thread involved,
288 * and uses a function that comes from GCC (--> libgcc_s.so) to do
289 * this. Unfortunately the developers of glibc decided to load the
290 * library on demand, which speeds up program start but can cause
291 * trouble here: Due to all the things NTPD does to limit its resource
292 * usage, this deferred load of libgcc_s does not always work once the
293 * restrictions are in effect.
294 *
295 * One way out of this was attempting a forced link against libgcc_s
296 * when possible because it makes the library available immediately
297 * without deferred load. (The symbol resolution would still be dynamic
298 * and on demand, but the code would already be in the process image.)
299 *
300 * This is a tricky thing to do, since it's not necessary everywhere,
301 * not possible everywhere, has shown to break the build of other
302 * programs in the NTP suite and is now generally frowned upon.
303 *
304 * So we take a different approach here: We creat a worker thread that does
305 * actually nothing except waiting for cancellation and cancel it. If
306 * this is done before all the limitations are put in place, the
307 * machinery is pre-heated and all the runtime stuff should be in place
308 * and useable when needed.
309 *
310 * This uses only the standard pthread API and should work with all
311 * implementations of pthreads. It is not necessary everywhere, but it's
312 * cheap enough to go on nearly unnoticed.
313 *
314 * Addendum: Bug 2954 showed that the assumption that this should work
315 * with all OS is wrong -- at least FreeBSD bombs heavily.
316 */
317#ifdef NEED_PTHREAD_WARMUP
318
319/* simple thread function: sleep until cancelled, just to exercise
320 * thread cancellation.
321 */
322static void*
323my_pthread_warmup_worker(
324	void *thread_args)
325{
326	(void)thread_args;
327	for (;;)
328		sleep(10);
329	return NULL;
330}
331
332/* pre-heat threading: create a thread and cancel it, just to exercise
333 * thread cancellation.
334 */
335static void
336my_pthread_warmup(void)
337{
338	pthread_t 	thread;
339	pthread_attr_t	thr_attr;
340	int       	rc;
341
342	pthread_attr_init(&thr_attr);
343#if defined(HAVE_PTHREAD_ATTR_GETSTACKSIZE) && \
344    defined(HAVE_PTHREAD_ATTR_SETSTACKSIZE) && \
345    defined(PTHREAD_STACK_MIN)
346	{
347		size_t ssmin = 32*1024;	/* 32kB should be minimum */
348		if (ssmin < PTHREAD_STACK_MIN)
349			ssmin = PTHREAD_STACK_MIN;
350		rc = pthread_attr_setstacksize(&thr_attr, ssmin);
351		if (0 != rc)
352			msyslog(LOG_ERR,
353				"my_pthread_warmup: pthread_attr_setstacksize() -> %s",
354				strerror(rc));
355	}
356#endif
357	rc = pthread_create(
358		&thread, &thr_attr, my_pthread_warmup_worker, NULL);
359	pthread_attr_destroy(&thr_attr);
360	if (0 != rc) {
361		msyslog(LOG_ERR,
362			"my_pthread_warmup: pthread_create() -> %s",
363			strerror(rc));
364	} else {
365		pthread_cancel(thread);
366		pthread_join(thread, NULL);
367	}
368}
369
370#endif /*defined(NEED_PTHREAD_WARMUP)*/
371
372#ifdef NEED_EARLY_FORK
373static void
374dummy_callback(void) { return; }
375
376static void
377fork_nonchroot_worker(void) {
378	getaddrinfo_sometime("localhost", "ntp", NULL, INITIAL_DNS_RETRY,
379			     (gai_sometime_callback)&dummy_callback, NULL);
380}
381#endif /* NEED_EARLY_FORK */
382
383void
384parse_cmdline_opts(
385	int *	pargc,
386	char ***pargv
387	)
388{
389	static int	parsed;
390	static int	optct;
391
392	if (!parsed)
393		optct = ntpOptionProcess(&ntpdOptions, *pargc, *pargv);
394
395	parsed = 1;
396
397	*pargc -= optct;
398	*pargv += optct;
399}
400
401
402#ifdef SIM
403int
404main(
405	int argc,
406	char *argv[]
407	)
408{
409	progname = argv[0];
410	parse_cmdline_opts(&argc, &argv);
411#ifdef DEBUG
412	debug = OPT_VALUE_SET_DEBUG_LEVEL;
413	DPRINTF(1, ("%s\n", Version));
414#endif
415
416	return ntpsim(argc, argv);
417}
418#elif defined(NO_MAIN_ALLOWED)
419CALL(ntpd,"ntpd",ntpdmain);
420#elif !defined(SYS_WINNT)
421int
422main(
423	int argc,
424	char *argv[]
425	)
426{
427	return ntpdmain(argc, argv);
428}
429#endif /* !SYS_WINNT */
430
431#ifdef _AIX
432/*
433 * OK. AIX is different than solaris in how it implements plock().
434 * If you do NOT adjust the stack limit, you will get the MAXIMUM
435 * stack size allocated and PINNED with you program. To check the
436 * value, use ulimit -a.
437 *
438 * To fix this, we create an automatic variable and set our stack limit
439 * to that PLUS 32KB of extra space (we need some headroom).
440 *
441 * This subroutine gets the stack address.
442 *
443 * Grover Davidson and Matt Ladendorf
444 *
445 */
446static char *
447get_aix_stack(void)
448{
449	char ch;
450	return (&ch);
451}
452
453/*
454 * Signal handler for SIGDANGER.
455 */
456static void
457catch_danger(int signo)
458{
459	msyslog(LOG_INFO, "ntpd: setpgid(): %m");
460	/* Make the system believe we'll free something, but don't do it! */
461	return;
462}
463#endif /* _AIX */
464
465/*
466 * Set the process priority
467 */
468#ifndef SIM
469static void
470set_process_priority(void)
471{
472
473# ifdef DEBUG
474	if (debug > 1)
475		msyslog(LOG_DEBUG, "set_process_priority: %s: priority_done is <%d>",
476			((priority_done)
477			 ? "Leave priority alone"
478			 : "Attempt to set priority"
479				),
480			priority_done);
481# endif /* DEBUG */
482
483# if defined(HAVE_SCHED_SETSCHEDULER)
484	if (!priority_done) {
485		extern int config_priority_override, config_priority;
486		int pmax, pmin;
487		struct sched_param sched;
488
489		pmax = sched_get_priority_max(SCHED_FIFO);
490		sched.sched_priority = pmax;
491		if ( config_priority_override ) {
492			pmin = sched_get_priority_min(SCHED_FIFO);
493			if ( config_priority > pmax )
494				sched.sched_priority = pmax;
495			else if ( config_priority < pmin )
496				sched.sched_priority = pmin;
497			else
498				sched.sched_priority = config_priority;
499		}
500		if ( sched_setscheduler(0, SCHED_FIFO, &sched) == -1 )
501			msyslog(LOG_ERR, "sched_setscheduler(): %m");
502		else
503			++priority_done;
504	}
505# endif /* HAVE_SCHED_SETSCHEDULER */
506# ifdef HAVE_RTPRIO
507#  ifdef RTP_SET
508	if (!priority_done) {
509		struct rtprio srtp;
510
511		srtp.type = RTP_PRIO_REALTIME;	/* was: RTP_PRIO_NORMAL */
512		srtp.prio = 0;		/* 0 (hi) -> RTP_PRIO_MAX (31,lo) */
513
514		if (rtprio(RTP_SET, getpid(), &srtp) < 0)
515			msyslog(LOG_ERR, "rtprio() error: %m");
516		else
517			++priority_done;
518	}
519#  else	/* !RTP_SET follows */
520	if (!priority_done) {
521		if (rtprio(0, 120) < 0)
522			msyslog(LOG_ERR, "rtprio() error: %m");
523		else
524			++priority_done;
525	}
526#  endif	/* !RTP_SET */
527# endif	/* HAVE_RTPRIO */
528# if defined(NTPD_PRIO) && NTPD_PRIO != 0
529#  ifdef HAVE_ATT_NICE
530	if (!priority_done) {
531		errno = 0;
532		if (-1 == nice (NTPD_PRIO) && errno != 0)
533			msyslog(LOG_ERR, "nice() error: %m");
534		else
535			++priority_done;
536	}
537#  endif	/* HAVE_ATT_NICE */
538#  ifdef HAVE_BSD_NICE
539	if (!priority_done) {
540		if (-1 == setpriority(PRIO_PROCESS, 0, NTPD_PRIO))
541			msyslog(LOG_ERR, "setpriority() error: %m");
542		else
543			++priority_done;
544	}
545#  endif	/* HAVE_BSD_NICE */
546# endif	/* NTPD_PRIO && NTPD_PRIO != 0 */
547	if (!priority_done)
548		msyslog(LOG_ERR, "set_process_priority: No way found to improve our priority");
549}
550#endif	/* !SIM */
551
552#if !defined(SIM) && !defined(SYS_WINNT)
553/*
554 * Detach from terminal (much like daemon())
555 * Nothe that this function calls exit()
556 */
557# ifdef HAVE_WORKING_FORK
558static void
559detach_from_terminal(
560	int pipe[2],
561	long wait_sync,
562	const char *logfilename
563	)
564{
565	pid_t	cpid;
566	int	exit_code;
567#  if !defined(HAVE_SETSID) && !defined (HAVE_SETPGID) && defined(TIOCNOTTY)
568	int		fid;
569#  endif
570#  ifdef _AIX
571	struct sigaction sa;
572#  endif
573
574	cpid = fork();
575	if (0 != cpid) {
576		/* parent */
577		if (-1 == cpid) {
578			msyslog(LOG_ERR, "fork: %m");
579			exit_code = EX_OSERR;
580		} else {
581			close(pipe[1]);
582			pipe[1] = -1;
583			exit_code = wait_child_sync_if(
584					pipe[0], wait_sync);
585			DPRINTF(1, ("sync_if: rc=%d\n", exit_code));
586			if (exit_code <= 0) {
587				/* probe daemon exit code -- wait for
588				 * child process if we have an unexpected
589				 * EOF on the monitor pipe.
590				 */
591				exit_code = wait_child_exit_if(
592						cpid, (exit_code < 0));
593				DPRINTF(1, ("exit_if: rc=%d\n", exit_code));
594			}
595		}
596		exit(exit_code);
597	}
598
599	/*
600	 * child/daemon
601	 * close all open files excepting waitsync_fd_to_close.
602	 * msyslog() unreliable until after init_logging().
603	 */
604	closelog();
605	if (syslog_file != NULL) {
606		fclose(syslog_file);
607		syslog_file = NULL;
608		syslogit = TRUE;
609	}
610	close_all_except(pipe[1]);
611	pipe[0] = -1;
612	INSIST(0 == open("/dev/null", 0) && 1 == dup2(0, 1) \
613		&& 2 == dup2(0, 2));
614
615	init_logging(progname, 0, TRUE);
616	/* we lost our logfile (if any) daemonizing */
617	setup_logfile(logfilename);
618
619#  ifdef SYS_DOMAINOS
620	{
621		uid_$t puid;
622		status_$t st;
623
624		proc2_$who_am_i(&puid);
625		proc2_$make_server(&puid, &st);
626	}
627#  endif	/* SYS_DOMAINOS */
628#  ifdef HAVE_SETSID
629	if (setsid() == (pid_t)-1)
630		msyslog(LOG_ERR, "setsid(): %m");
631#  elif defined(HAVE_SETPGID)
632	if (setpgid(0, 0) == -1)
633		msyslog(LOG_ERR, "setpgid(): %m");
634#  else		/* !HAVE_SETSID && !HAVE_SETPGID follows */
635#   ifdef TIOCNOTTY
636	fid = open("/dev/tty", 2);
637	if (fid >= 0) {
638		ioctl(fid, (u_long)TIOCNOTTY, NULL);
639		close(fid);
640	}
641#   endif	/* TIOCNOTTY */
642	ntp_setpgrp(0, getpid());
643#  endif	/* !HAVE_SETSID && !HAVE_SETPGID */
644#  ifdef _AIX
645	/* Don't get killed by low-on-memory signal. */
646	sa.sa_handler = catch_danger;
647	sigemptyset(&sa.sa_mask);
648	sa.sa_flags = SA_RESTART;
649	sigaction(SIGDANGER, &sa, NULL);
650#  endif	/* _AIX */
651
652	return;
653}
654# endif /* HAVE_WORKING_FORK */
655
656#ifdef HAVE_DROPROOT
657/*
658 * Map user name/number to user ID
659*/
660static int
661map_user(
662	)
663{
664	char *endp;
665
666	if (isdigit((unsigned char)*user)) {
667		sw_uid = (uid_t)strtoul(user, &endp, 0);
668		if (*endp != '\0')
669			goto getuser;
670
671		if ((pw = getpwuid(sw_uid)) != NULL) {
672			free(user);
673			user = estrdup(pw->pw_name);
674			sw_gid = pw->pw_gid;
675		} else {
676			errno = 0;
677			msyslog(LOG_ERR, "Cannot find user ID %s", user);
678			return 0;
679		}
680
681	} else {
682getuser:
683		errno = 0;
684		if ((pw = getpwnam(user)) != NULL) {
685			sw_uid = pw->pw_uid;
686			sw_gid = pw->pw_gid;
687		} else {
688			if (errno)
689				msyslog(LOG_ERR, "getpwnam(%s) failed: %m", user);
690			else
691				msyslog(LOG_ERR, "Cannot find user `%s'", user);
692			return 0;
693		}
694	}
695
696	return 1;
697}
698
699/*
700 * Map group name/number to group ID
701*/
702static int
703map_group(void)
704{
705	char *endp;
706
707	if (isdigit((unsigned char)*group)) {
708		sw_gid = (gid_t)strtoul(group, &endp, 0);
709		if (*endp != '\0')
710			goto getgroup;
711	} else {
712getgroup:
713		if ((gr = getgrnam(group)) != NULL) {
714			sw_gid = gr->gr_gid;
715		} else {
716			errno = 0;
717			msyslog(LOG_ERR, "Cannot find group `%s'", group);
718			return 0;
719		}
720	}
721
722	return 1;
723}
724
725static int
726set_group_ids(void)
727{
728	if (user && initgroups(user, sw_gid)) {
729		msyslog(LOG_ERR, "Cannot initgroups() to user `%s': %m", user);
730		return 0;
731	}
732	if (group && setgid(sw_gid)) {
733		msyslog(LOG_ERR, "Cannot setgid() to group `%s': %m", group);
734		return 0;
735	}
736	if (group && setegid(sw_gid)) {
737		msyslog(LOG_ERR, "Cannot setegid() to group `%s': %m", group);
738		return 0;
739	}
740	if (group) {
741		if (0 != setgroups(1, &sw_gid)) {
742			msyslog(LOG_ERR, "setgroups(1, %d) failed: %m", sw_gid);
743			return 0;
744		}
745	}
746	else if (pw)
747		if (0 != initgroups(pw->pw_name, pw->pw_gid)) {
748			msyslog(LOG_ERR, "initgroups(<%s>, %d) filed: %m", pw->pw_name, pw->pw_gid);
749			return 0;
750		}
751	return 1;
752}
753
754static int
755set_user_ids(void)
756{
757	if (user && setuid(sw_uid)) {
758		msyslog(LOG_ERR, "Cannot setuid() to user `%s': %m", user);
759		return 0;
760	}
761	if (user && seteuid(sw_uid)) {
762		msyslog(LOG_ERR, "Cannot seteuid() to user `%s': %m", user);
763		return 0;
764	}
765	return 1;
766}
767
768/*
769 * Change (effective) user and group IDs, also initialize the supplementary group access list
770 */
771int set_user_group_ids(void);
772int
773set_user_group_ids(void)
774{
775	/* If the the user was already mapped, no need to map it again */
776	if ((NULL != user) && (0 == sw_uid)) {
777		if (0 == map_user())
778			exit (-1);
779	}
780	/* same applies for the group */
781	if ((NULL != group) && (0 == sw_gid)) {
782		if (0 == map_group())
783			exit (-1);
784	}
785
786	if (getegid() != sw_gid && 0 == set_group_ids())
787		return 0;
788	if (geteuid() != sw_uid && 0 == set_user_ids())
789		return 0;
790
791	return 1;
792}
793#endif /* HAVE_DROPROOT */
794#endif /* !SIM */
795
796/*
797 * Main program.  Initialize us, disconnect us from the tty if necessary,
798 * and loop waiting for I/O and/or timer expiries.
799 */
800#ifndef SIM
801int
802ntpdmain(
803	int argc,
804	char *argv[]
805	)
806{
807	l_fp		now;
808	struct recvbuf *rbuf;
809	const char *	logfilename;
810# ifdef HAVE_UMASK
811	mode_t		uv;
812# endif
813# if defined(HAVE_GETUID) && !defined(MPE) /* MPE lacks the concept of root */
814	uid_t		uid;
815# endif
816# if defined(HAVE_WORKING_FORK)
817	long		wait_sync = 0;
818# endif	/* HAVE_WORKING_FORK*/
819# ifdef SCO5_CLOCK
820	int		fd;
821	int		zero;
822# endif
823
824# ifdef NEED_PTHREAD_WARMUP
825	my_pthread_warmup();
826# endif
827
828# ifdef HAVE_UMASK
829	uv = umask(0);
830	if (uv)
831		umask(uv);
832	else
833		umask(022);
834# endif
835	saved_argc = argc;
836	saved_argv = argv;
837	progname = argv[0];
838	initializing = TRUE;		/* mark that we are initializing */
839	parse_cmdline_opts(&argc, &argv);
840# ifdef DEBUG
841	debug = OPT_VALUE_SET_DEBUG_LEVEL;
842#  ifdef HAVE_SETLINEBUF
843	setlinebuf(stdout);
844#  endif
845# endif
846
847	if (HAVE_OPT(NOFORK) || HAVE_OPT(QUIT)
848# ifdef DEBUG
849	    || debug
850# endif
851	    || HAVE_OPT(SAVECONFIGQUIT))
852		nofork = TRUE;
853
854	init_logging(progname, NLOG_SYNCMASK, TRUE);
855	/* honor -l/--logfile option to log to a file */
856	if (HAVE_OPT(LOGFILE)) {
857		logfilename = OPT_ARG(LOGFILE);
858		syslogit = FALSE;
859		change_logfile(logfilename, FALSE);
860	} else {
861		logfilename = NULL;
862		if (nofork)
863			msyslog_term = TRUE;
864		if (HAVE_OPT(SAVECONFIGQUIT))
865			syslogit = FALSE;
866	}
867	msyslog(LOG_NOTICE, "%s: Starting", Version);
868
869	{
870		int i;
871		char buf[1024];	/* Secret knowledge of msyslog buf length */
872		char *cp = buf;
873
874		/* Note that every arg has an initial space character */
875		snprintf(cp, sizeof(buf), "Command line:");
876		cp += strlen(cp);
877
878		for (i = 0; i < saved_argc ; ++i) {
879			snprintf(cp, sizeof(buf) - (cp - buf),
880				" %s", saved_argv[i]);
881			cp += strlen(cp);
882		}
883		msyslog(LOG_NOTICE, "%s", buf);
884	}
885
886	msyslog(LOG_NOTICE, "----------------------------------------------------");
887	msyslog(LOG_NOTICE, "ntp-4 is maintained by Network Time Foundation,");
888	msyslog(LOG_NOTICE, "Inc. (NTF), a non-profit 501(c)(3) public-benefit");
889	msyslog(LOG_NOTICE, "corporation.  Support and training for ntp-4 are");
890	msyslog(LOG_NOTICE, "available at https://www.nwtime.org/support");
891	msyslog(LOG_NOTICE, "----------------------------------------------------");
892
893	/*
894	 * Install trap handlers to log errors and assertion failures.
895	 * Default handlers print to stderr which doesn't work if detached.
896	 */
897	isc_assertion_setcallback(assertion_failed);
898	isc_error_setfatal(library_fatal_error);
899	isc_error_setunexpected(library_unexpected_error);
900
901	/* MPE lacks the concept of root */
902# if defined(HAVE_GETUID) && !defined(MPE)
903	uid = getuid();
904	if (uid && !HAVE_OPT( SAVECONFIGQUIT )) {
905		msyslog_term = TRUE;
906		msyslog(LOG_ERR,
907			"must be run as root, not uid %ld", (long)uid);
908		exit(1);
909	}
910# endif
911
912/*
913 * Enable the Multi-Media Timer for Windows?
914 */
915# ifdef SYS_WINNT
916	if (HAVE_OPT( MODIFYMMTIMER ))
917		set_mm_timer(MM_TIMER_HIRES);
918# endif
919
920#ifdef HAVE_DNSREGISTRATION
921/*
922 * Enable mDNS registrations?
923 */
924	if (HAVE_OPT( MDNS )) {
925		mdnsreg = TRUE;
926	}
927#endif  /* HAVE_DNSREGISTRATION */
928
929	if (HAVE_OPT( NOVIRTUALIPS ))
930		listen_to_virtual_ips = 0;
931
932	/*
933	 * --interface, listen on specified interfaces
934	 */
935	if (HAVE_OPT( INTERFACE )) {
936		int		ifacect = STACKCT_OPT( INTERFACE );
937		const char**	ifaces  = STACKLST_OPT( INTERFACE );
938		sockaddr_u	addr;
939
940		while (ifacect-- > 0) {
941			add_nic_rule(
942				is_ip_address(*ifaces, AF_UNSPEC, &addr)
943					? MATCH_IFADDR
944					: MATCH_IFNAME,
945				*ifaces, -1, ACTION_LISTEN);
946			ifaces++;
947		}
948	}
949
950	if (HAVE_OPT( NICE ))
951		priority_done = 0;
952
953# ifdef HAVE_SCHED_SETSCHEDULER
954	if (HAVE_OPT( PRIORITY )) {
955		config_priority = OPT_VALUE_PRIORITY;
956		config_priority_override = 1;
957		priority_done = 0;
958	}
959# endif
960
961# ifdef HAVE_WORKING_FORK
962	/* make sure the FDs are initialised
963	 *
964	 * note: if WAIT_SYNC is requested, we *have* to fork. This will
965	 * overide any '-n' (nofork) or '-d' (debug) option presented on
966	 * the command line!
967	 */
968	if (HAVE_OPT(WAIT_SYNC)) {
969		wait_sync = OPT_VALUE_WAIT_SYNC;
970		if (wait_sync <= 0)
971			wait_sync = 0;
972		else
973			nofork = FALSE;
974	}
975	if ( !nofork && pipe(daemon_pipe)) {
976		msyslog(LOG_ERR,
977			"Pipe creation failed for --wait-sync/daemon: %m");
978		exit(EX_OSERR);
979	}
980# endif	/* HAVE_WORKING_FORK */
981
982	init_lib();
983# ifdef SYS_WINNT
984	/*
985	 * Make sure the service is initialized before we do anything else
986	 */
987	ntservice_init();
988
989	/*
990	 * Start interpolation thread, must occur before first
991	 * get_systime()
992	 */
993	init_winnt_time();
994# endif
995	/*
996	 * Initialize random generator and public key pair
997	 */
998	get_systime(&now);
999
1000	ntp_srandom((int)(now.l_i * now.l_uf));
1001
1002	/*
1003	 * Detach us from the terminal.  May need an #ifndef GIZMO.
1004	 */
1005# ifdef HAVE_WORKING_FORK
1006	if (!nofork) {
1007		detach_from_terminal(daemon_pipe, wait_sync, logfilename);
1008	}
1009# endif		/* HAVE_WORKING_FORK */
1010
1011# ifdef SCO5_CLOCK
1012	/*
1013	 * SCO OpenServer's system clock offers much more precise timekeeping
1014	 * on the base CPU than the other CPUs (for multiprocessor systems),
1015	 * so we must lock to the base CPU.
1016	 */
1017	fd = open("/dev/at1", O_RDONLY);
1018	if (fd >= 0) {
1019		zero = 0;
1020		if (ioctl(fd, ACPU_LOCK, &zero) < 0)
1021			msyslog(LOG_ERR, "cannot lock to base CPU: %m");
1022		close(fd);
1023	}
1024# endif
1025
1026	/* Setup stack size in preparation for locking pages in memory. */
1027# if defined(HAVE_MLOCKALL)
1028#  ifdef HAVE_SETRLIMIT
1029	ntp_rlimit(RLIMIT_STACK, DFLT_RLIMIT_STACK * 4096, 4096, "4k");
1030#   if defined(RLIMIT_MEMLOCK) && defined(DFLT_RLIMIT_MEMLOCK) && DFLT_RLIMIT_MEMLOCK != -1
1031	/*
1032	 * The default RLIMIT_MEMLOCK is very low on Linux systems.
1033	 * Unless we increase this limit malloc calls are likely to
1034	 * fail if we drop root privilege.  To be useful the value
1035	 * has to be larger than the largest ntpd resident set size.
1036	 */
1037	ntp_rlimit(RLIMIT_MEMLOCK, DFLT_RLIMIT_MEMLOCK * 1024 * 1024, 1024 * 1024, "MB");
1038#   endif	/* RLIMIT_MEMLOCK */
1039#  endif	/* HAVE_SETRLIMIT */
1040# else	/* !HAVE_MLOCKALL follows */
1041#  ifdef HAVE_PLOCK
1042#   ifdef PROCLOCK
1043#    ifdef _AIX
1044	/*
1045	 * set the stack limit for AIX for plock().
1046	 * see get_aix_stack() for more info.
1047	 */
1048	if (ulimit(SET_STACKLIM, (get_aix_stack() - 8 * 4096)) < 0)
1049		msyslog(LOG_ERR,
1050			"Cannot adjust stack limit for plock: %m");
1051#    endif	/* _AIX */
1052#   endif	/* PROCLOCK */
1053#  endif	/* HAVE_PLOCK */
1054# endif	/* !HAVE_MLOCKALL */
1055
1056	/*
1057	 * Set up signals we pay attention to locally.
1058	 */
1059# ifdef SIGDIE1
1060	signal_no_reset(SIGDIE1, finish);
1061	signal_no_reset(SIGDIE2, finish);
1062	signal_no_reset(SIGDIE3, finish);
1063	signal_no_reset(SIGDIE4, finish);
1064# endif
1065# ifdef SIGBUS
1066	signal_no_reset(SIGBUS, finish);
1067# endif
1068
1069# if !defined(SYS_WINNT) && !defined(VMS)
1070#  ifdef DEBUG
1071	(void) signal_no_reset(MOREDEBUGSIG, moredebug);
1072	(void) signal_no_reset(LESSDEBUGSIG, lessdebug);
1073#  else
1074	(void) signal_no_reset(MOREDEBUGSIG, no_debug);
1075	(void) signal_no_reset(LESSDEBUGSIG, no_debug);
1076#  endif	/* DEBUG */
1077# endif	/* !SYS_WINNT && !VMS */
1078
1079	/*
1080	 * Set up signals we should never pay attention to.
1081	 */
1082# ifdef SIGPIPE
1083	signal_no_reset(SIGPIPE, SIG_IGN);
1084# endif
1085
1086	/*
1087	 * Call the init_ routines to initialize the data structures.
1088	 *
1089	 * Exactly what command-line options are we expecting here?
1090	 */
1091	INIT_SSL();
1092	init_auth();
1093	init_util();
1094	init_restrict();
1095	init_mon();
1096	init_timer();
1097	init_request();
1098	init_control();
1099	init_peer();
1100# ifdef REFCLOCK
1101	init_refclock();
1102# endif
1103	set_process_priority();
1104	init_proto();		/* Call at high priority */
1105	init_io();
1106	init_loopfilter();
1107	mon_start(MON_ON);	/* monitor on by default now	  */
1108				/* turn off in config if unwanted */
1109
1110	/*
1111	 * Get the configuration.  This is done in a separate module
1112	 * since this will definitely be different for the gizmo board.
1113	 */
1114	getconfig(argc, argv);
1115
1116	if (-1 == cur_memlock) {
1117# if defined(HAVE_MLOCKALL)
1118		/*
1119		 * lock the process into memory
1120		 */
1121		if (   !HAVE_OPT(SAVECONFIGQUIT)
1122#  ifdef RLIMIT_MEMLOCK
1123		    && -1 != DFLT_RLIMIT_MEMLOCK
1124#  endif
1125		    && 0 != mlockall(MCL_CURRENT|MCL_FUTURE))
1126			msyslog(LOG_ERR, "mlockall(): %m");
1127# else	/* !HAVE_MLOCKALL follows */
1128#  ifdef HAVE_PLOCK
1129#   ifdef PROCLOCK
1130		/*
1131		 * lock the process into memory
1132		 */
1133		if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(PROCLOCK))
1134			msyslog(LOG_ERR, "plock(PROCLOCK): %m");
1135#   else	/* !PROCLOCK follows  */
1136#    ifdef TXTLOCK
1137		/*
1138		 * Lock text into ram
1139		 */
1140		if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(TXTLOCK))
1141			msyslog(LOG_ERR, "plock(TXTLOCK) error: %m");
1142#    else	/* !TXTLOCK follows */
1143		msyslog(LOG_ERR, "plock() - don't know what to lock!");
1144#    endif	/* !TXTLOCK */
1145#   endif	/* !PROCLOCK */
1146#  endif	/* HAVE_PLOCK */
1147# endif	/* !HAVE_MLOCKALL */
1148	}
1149
1150	loop_config(LOOP_DRIFTINIT, 0);
1151	report_event(EVNT_SYSRESTART, NULL, NULL);
1152	initializing = FALSE;
1153
1154# ifdef HAVE_LINUX_CAPABILITIES
1155	{
1156		/*  Check that setting capabilities actually works; we might be
1157		 *  run on a kernel with disabled capabilities. We must not
1158		 *  drop privileges in this case.
1159		 */
1160		cap_t caps;
1161		caps = cap_from_text("cap_sys_time,cap_setuid,cap_setgid,cap_sys_chroot,cap_net_bind_service=pe");
1162		if ( ! caps) {
1163			msyslog( LOG_ERR, "cap_from_text() failed: %m" );
1164			exit(-1);
1165		}
1166		have_caps = (cap_set_proc(caps) == 0);
1167		cap_free(caps);	/* caps not NULL here! */
1168	}
1169# endif /* HAVE_LINUX_CAPABILITIES */
1170
1171# ifdef HAVE_DROPROOT
1172#  ifdef HAVE_LINUX_CAPABILITIES
1173	if (droproot && have_caps) {
1174#  else
1175	if (droproot) {
1176#  endif /*HAVE_LINUX_CAPABILITIES*/
1177
1178#  ifdef NEED_EARLY_FORK
1179		fork_nonchroot_worker();
1180#  endif
1181
1182		/* Drop super-user privileges and chroot now if the OS supports this */
1183
1184#  ifdef HAVE_LINUX_CAPABILITIES
1185		/* set flag: keep privileges accross setuid() call (we only really need cap_sys_time): */
1186		if (prctl( PR_SET_KEEPCAPS, 1L, 0L, 0L, 0L ) == -1) {
1187			msyslog( LOG_ERR, "prctl( PR_SET_KEEPCAPS, 1L ) failed: %m" );
1188			exit(-1);
1189		}
1190#  elif HAVE_SOLARIS_PRIVS
1191		/* Nothing to do here */
1192#  else
1193		/* we need a user to switch to */
1194		if (user == NULL) {
1195			msyslog(LOG_ERR, "Need user name to drop root privileges (see -u flag!)" );
1196			exit(-1);
1197		}
1198#  endif	/* HAVE_LINUX_CAPABILITIES || HAVE_SOLARIS_PRIVS */
1199
1200		if (user != NULL) {
1201			if (0 == map_user())
1202				exit (-1);
1203		}
1204		if (group != NULL) {
1205			if (0 == map_group())
1206				exit (-1);
1207		}
1208
1209		if (chrootdir ) {
1210			/* make sure cwd is inside the jail: */
1211			if (chdir(chrootdir)) {
1212				msyslog(LOG_ERR, "Cannot chdir() to `%s': %m", chrootdir);
1213				exit (-1);
1214			}
1215			if (chroot(chrootdir)) {
1216				msyslog(LOG_ERR, "Cannot chroot() to `%s': %m", chrootdir);
1217				exit (-1);
1218			}
1219			if (chdir("/")) {
1220				msyslog(LOG_ERR, "Cannot chdir() to`root after chroot(): %m");
1221				exit (-1);
1222			}
1223		}
1224#  ifdef HAVE_SOLARIS_PRIVS
1225		if ((lowprivs = priv_str_to_set(LOWPRIVS, ",", NULL)) == NULL) {
1226			msyslog(LOG_ERR, "priv_str_to_set() failed:%m");
1227			exit(-1);
1228		}
1229		if ((highprivs = priv_allocset()) == NULL) {
1230			msyslog(LOG_ERR, "priv_allocset() failed:%m");
1231			exit(-1);
1232		}
1233		(void) getppriv(PRIV_PERMITTED, highprivs);
1234		(void) priv_intersect(highprivs, lowprivs);
1235		if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1236			msyslog(LOG_ERR, "setppriv() failed:%m");
1237			exit(-1);
1238		}
1239#  endif /* HAVE_SOLARIS_PRIVS */
1240		if (0 == set_user_group_ids())
1241			exit(-1);
1242
1243#  if !defined(HAVE_LINUX_CAPABILITIES) && !defined(HAVE_SOLARIS_PRIVS)
1244		/*
1245		 * for now assume that the privilege to bind to privileged ports
1246		 * is associated with running with uid 0 - should be refined on
1247		 * ports that allow binding to NTP_PORT with uid != 0
1248		 */
1249		disable_dynamic_updates |= (sw_uid != 0);  /* also notifies routing message listener */
1250#  endif /* !HAVE_LINUX_CAPABILITIES && !HAVE_SOLARIS_PRIVS */
1251
1252		if (disable_dynamic_updates && interface_interval) {
1253			interface_interval = 0;
1254			msyslog(LOG_INFO, "running as non-root disables dynamic interface tracking");
1255		}
1256
1257#  ifdef HAVE_LINUX_CAPABILITIES
1258		{
1259			/*
1260			 *  We may be running under non-root uid now, but we still hold full root privileges!
1261			 *  We drop all of them, except for the crucial one or two: cap_sys_time and
1262			 *  cap_net_bind_service if doing dynamic interface tracking.
1263			 */
1264			cap_t caps;
1265			char *captext;
1266
1267			captext = (0 != interface_interval)
1268				      ? "cap_sys_time,cap_net_bind_service=pe"
1269				      : "cap_sys_time=pe";
1270			caps = cap_from_text(captext);
1271			if (!caps) {
1272				msyslog(LOG_ERR,
1273					"cap_from_text(%s) failed: %m",
1274					captext);
1275				exit(-1);
1276			}
1277			if (-1 == cap_set_proc(caps)) {
1278				msyslog(LOG_ERR,
1279					"cap_set_proc() failed to drop root privs: %m");
1280				exit(-1);
1281			}
1282			cap_free(caps);
1283		}
1284#  endif	/* HAVE_LINUX_CAPABILITIES */
1285#  ifdef HAVE_SOLARIS_PRIVS
1286		if (priv_delset(lowprivs, "proc_setid") == -1) {
1287			msyslog(LOG_ERR, "priv_delset() failed:%m");
1288			exit(-1);
1289		}
1290		if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1291			msyslog(LOG_ERR, "setppriv() failed:%m");
1292			exit(-1);
1293		}
1294		priv_freeset(lowprivs);
1295		priv_freeset(highprivs);
1296#  endif /* HAVE_SOLARIS_PRIVS */
1297		root_dropped = TRUE;
1298		fork_deferred_worker();
1299	}	/* if (droproot) */
1300# endif	/* HAVE_DROPROOT */
1301
1302/* libssecomp sandboxing */
1303#if defined (LIBSECCOMP) && (KERN_SECCOMP)
1304	scmp_filter_ctx ctx;
1305
1306	if ((ctx = seccomp_init(SCMP_ACT_KILL)) < 0)
1307		msyslog(LOG_ERR, "%s: seccomp_init(SCMP_ACT_KILL) failed: %m", __func__);
1308	else {
1309		msyslog(LOG_DEBUG, "%s: seccomp_init(SCMP_ACT_KILL) succeeded", __func__);
1310	}
1311
1312#ifdef __x86_64__
1313int scmp_sc[] = {
1314	SCMP_SYS(adjtimex),
1315	SCMP_SYS(bind),
1316	SCMP_SYS(brk),
1317	SCMP_SYS(chdir),
1318	SCMP_SYS(clock_gettime),
1319	SCMP_SYS(clock_settime),
1320	SCMP_SYS(close),
1321	SCMP_SYS(connect),
1322	SCMP_SYS(exit_group),
1323	SCMP_SYS(fstat),
1324	SCMP_SYS(fsync),
1325	SCMP_SYS(futex),
1326	SCMP_SYS(getitimer),
1327	SCMP_SYS(getsockname),
1328	SCMP_SYS(ioctl),
1329	SCMP_SYS(lseek),
1330	SCMP_SYS(madvise),
1331	SCMP_SYS(mmap),
1332	SCMP_SYS(munmap),
1333	SCMP_SYS(open),
1334	SCMP_SYS(poll),
1335	SCMP_SYS(read),
1336	SCMP_SYS(recvmsg),
1337	SCMP_SYS(rename),
1338	SCMP_SYS(rt_sigaction),
1339	SCMP_SYS(rt_sigprocmask),
1340	SCMP_SYS(rt_sigreturn),
1341	SCMP_SYS(select),
1342	SCMP_SYS(sendto),
1343	SCMP_SYS(setitimer),
1344	SCMP_SYS(setsid),
1345	SCMP_SYS(socket),
1346	SCMP_SYS(stat),
1347	SCMP_SYS(time),
1348	SCMP_SYS(write),
1349};
1350#endif
1351#ifdef __i386__
1352int scmp_sc[] = {
1353	SCMP_SYS(_newselect),
1354	SCMP_SYS(adjtimex),
1355	SCMP_SYS(brk),
1356	SCMP_SYS(chdir),
1357	SCMP_SYS(clock_gettime),
1358	SCMP_SYS(clock_settime),
1359	SCMP_SYS(close),
1360	SCMP_SYS(exit_group),
1361	SCMP_SYS(fsync),
1362	SCMP_SYS(futex),
1363	SCMP_SYS(getitimer),
1364	SCMP_SYS(madvise),
1365	SCMP_SYS(mmap),
1366	SCMP_SYS(mmap2),
1367	SCMP_SYS(munmap),
1368	SCMP_SYS(open),
1369	SCMP_SYS(poll),
1370	SCMP_SYS(read),
1371	SCMP_SYS(rename),
1372	SCMP_SYS(rt_sigaction),
1373	SCMP_SYS(rt_sigprocmask),
1374	SCMP_SYS(select),
1375	SCMP_SYS(setitimer),
1376	SCMP_SYS(setsid),
1377	SCMP_SYS(sigprocmask),
1378	SCMP_SYS(sigreturn),
1379	SCMP_SYS(socketcall),
1380	SCMP_SYS(stat64),
1381	SCMP_SYS(time),
1382	SCMP_SYS(write),
1383};
1384#endif
1385	{
1386		int i;
1387
1388		for (i = 0; i < COUNTOF(scmp_sc); i++) {
1389			if (seccomp_rule_add(ctx,
1390			    SCMP_ACT_ALLOW, scmp_sc[i], 0) < 0) {
1391				msyslog(LOG_ERR,
1392				    "%s: seccomp_rule_add() failed: %m",
1393				    __func__);
1394			}
1395		}
1396	}
1397
1398	if (seccomp_load(ctx) < 0)
1399		msyslog(LOG_ERR, "%s: seccomp_load() failed: %m",
1400		    __func__);
1401	else {
1402		msyslog(LOG_DEBUG, "%s: seccomp_load() succeeded", __func__);
1403	}
1404#endif /* LIBSECCOMP and KERN_SECCOMP */
1405
1406#if defined(SYS_WINNT)
1407	ntservice_isup();
1408#elif defined(HAVE_WORKING_FORK)
1409	if (daemon_pipe[1] != -1) {
1410		write(daemon_pipe[1], "R\n", 2);
1411	}
1412#endif /* HAVE_WORKING_FORK */
1413
1414# ifndef HAVE_IO_COMPLETION_PORT
1415	BLOCK_IO_AND_ALARM();
1416	was_alarmed = FALSE;
1417# endif
1418
1419	for (;;) {
1420#if !defined(SIM) && defined(SIGDIE1)
1421		if (signalled)
1422			finish_safe(signo);
1423#endif
1424# ifdef HAVE_IO_COMPLETION_PORT
1425		GetReceivedBuffers();
1426
1427# else /* normal I/O */
1428		if (alarm_flag) {	/* alarmed? */
1429			was_alarmed = TRUE;
1430			alarm_flag = FALSE;
1431		}
1432
1433		/* collect async name/addr results */
1434		if (!was_alarmed)
1435		    harvest_blocking_responses();
1436
1437		if (!was_alarmed && !has_full_recv_buffer()) {
1438			/*
1439			 * Nothing to do.  Wait for something.
1440			 */
1441			io_handler();
1442		}
1443
1444		if (alarm_flag) {	/* alarmed? */
1445			was_alarmed = TRUE;
1446			alarm_flag = FALSE;
1447		}
1448
1449		if (was_alarmed) {
1450			UNBLOCK_IO_AND_ALARM();
1451			/*
1452			 * Out here, signals are unblocked.  Call timer routine
1453			 * to process expiry.
1454			 */
1455			timer();
1456			was_alarmed = FALSE;
1457			BLOCK_IO_AND_ALARM();
1458		}
1459
1460# endif		/* !HAVE_IO_COMPLETION_PORT */
1461
1462# ifdef DEBUG_TIMING
1463		{
1464			l_fp pts;
1465			l_fp tsa, tsb;
1466			int bufcount = 0;
1467
1468			get_systime(&pts);
1469			tsa = pts;
1470# endif
1471			rbuf = get_full_recv_buffer();
1472			while (rbuf != NULL) {
1473				if (alarm_flag) {
1474					was_alarmed = TRUE;
1475					alarm_flag = FALSE;
1476				}
1477				UNBLOCK_IO_AND_ALARM();
1478
1479				if (was_alarmed) {
1480					/* avoid timer starvation during lengthy I/O handling */
1481					timer();
1482					was_alarmed = FALSE;
1483				}
1484
1485				/*
1486				 * Call the data procedure to handle each received
1487				 * packet.
1488				 */
1489				if (rbuf->receiver != NULL) {
1490# ifdef DEBUG_TIMING
1491					l_fp dts = pts;
1492
1493					L_SUB(&dts, &rbuf->recv_time);
1494					DPRINTF(2, ("processing timestamp delta %s (with prec. fuzz)\n", lfptoa(&dts, 9)));
1495					collect_timing(rbuf, "buffer processing delay", 1, &dts);
1496					bufcount++;
1497# endif
1498					(*rbuf->receiver)(rbuf);
1499				} else {
1500					msyslog(LOG_ERR, "fatal: receive buffer callback NULL");
1501					abort();
1502				}
1503
1504				BLOCK_IO_AND_ALARM();
1505				freerecvbuf(rbuf);
1506				rbuf = get_full_recv_buffer();
1507			}
1508# ifdef DEBUG_TIMING
1509			get_systime(&tsb);
1510			L_SUB(&tsb, &tsa);
1511			if (bufcount) {
1512				collect_timing(NULL, "processing", bufcount, &tsb);
1513				DPRINTF(2, ("processing time for %d buffers %s\n", bufcount, lfptoa(&tsb, 9)));
1514			}
1515		}
1516# endif
1517
1518		/*
1519		 * Go around again
1520		 */
1521
1522# ifdef HAVE_DNSREGISTRATION
1523		if (mdnsreg && (current_time - mdnsreg ) > 60 && mdnstries && sys_leap != LEAP_NOTINSYNC) {
1524			mdnsreg = current_time;
1525			msyslog(LOG_INFO, "Attempting to register mDNS");
1526			if ( DNSServiceRegister (&mdns, 0, 0, NULL, "_ntp._udp", NULL, NULL,
1527			    htons(NTP_PORT), 0, NULL, NULL, NULL) != kDNSServiceErr_NoError ) {
1528				if (!--mdnstries) {
1529					msyslog(LOG_ERR, "Unable to register mDNS, giving up.");
1530				} else {
1531					msyslog(LOG_INFO, "Unable to register mDNS, will try later.");
1532				}
1533			} else {
1534				msyslog(LOG_INFO, "mDNS service registered.");
1535				mdnsreg = FALSE;
1536			}
1537		}
1538# endif /* HAVE_DNSREGISTRATION */
1539
1540	}
1541	UNBLOCK_IO_AND_ALARM();
1542	return 1;
1543}
1544#endif	/* !SIM */
1545
1546
1547#if !defined(SIM) && defined(SIGDIE1)
1548/*
1549 * finish - exit gracefully
1550 */
1551static void
1552finish_safe(
1553	int	sig
1554	)
1555{
1556	const char *sig_desc;
1557
1558	sig_desc = NULL;
1559#ifdef HAVE_STRSIGNAL
1560	sig_desc = strsignal(sig);
1561#endif
1562	if (sig_desc == NULL)
1563		sig_desc = "";
1564	msyslog(LOG_NOTICE, "%s exiting on signal %d (%s)", progname,
1565		sig, sig_desc);
1566	/* See Bug 2513 and Bug 2522 re the unlink of PIDFILE */
1567# ifdef HAVE_DNSREGISTRATION
1568	if (mdns != NULL)
1569		DNSServiceRefDeallocate(mdns);
1570# endif
1571	peer_cleanup();
1572	exit(0);
1573}
1574
1575static RETSIGTYPE
1576finish(
1577	int	sig
1578	)
1579{
1580	signalled = 1;
1581	signo = sig;
1582}
1583
1584#endif	/* !SIM && SIGDIE1 */
1585
1586
1587#ifndef SIM
1588/*
1589 * wait_child_sync_if - implements parent side of -w/--wait-sync
1590 */
1591# ifdef HAVE_WORKING_FORK
1592
1593static int
1594wait_child_sync_if(
1595	int		pipe_read_fd,
1596	unsigned long	wait_sync
1597	)
1598{
1599	int	rc;
1600	char	ch;
1601	time_t	wait_end_time;
1602	time_t	cur_time;
1603	time_t	wait_rem;
1604	fd_set	readset;
1605	struct timeval wtimeout;
1606
1607	/* we wait a bit for the child in *any* case, because on failure
1608	 * of the child we have to get and inspect the exit code!
1609	 */
1610	wait_end_time = time(NULL);
1611	if (wait_sync)
1612		wait_end_time += wait_sync;
1613	else
1614		wait_end_time += 30;
1615
1616	do {
1617		cur_time = time(NULL);
1618		wait_rem = (wait_end_time > cur_time)
1619				? (wait_end_time - cur_time)
1620				: 0;
1621		wtimeout.tv_sec = wait_rem;
1622		wtimeout.tv_usec = 0;
1623		FD_ZERO(&readset);
1624		FD_SET(pipe_read_fd, &readset);
1625		rc = select(pipe_read_fd + 1, &readset, NULL, NULL,
1626			    &wtimeout);
1627		if (-1 == rc) {
1628			if (EINTR == errno)
1629				continue;
1630			msyslog(LOG_ERR,
1631				"daemon startup: select failed: %m");
1632			return EX_IOERR;
1633		}
1634		if (0 == rc) {
1635			/*
1636			 * select() indicated a timeout, but in case
1637			 * its timeouts are affected by a step of the
1638			 * system clock, select() again with a zero
1639			 * timeout to confirm.
1640			 */
1641			FD_ZERO(&readset);
1642			FD_SET(pipe_read_fd, &readset);
1643			wtimeout.tv_sec = 0;
1644			wtimeout.tv_usec = 0;
1645			rc = select(pipe_read_fd + 1, &readset, NULL,
1646				    NULL, &wtimeout);
1647			if (0 == rc)	/* select() timeout */
1648				break;
1649		}
1650		rc = read(pipe_read_fd, &ch, 1);
1651		if (rc == 0) {
1652			DPRINTF(2, ("daemon control: got EOF\n"));
1653			return -1;	/* unexpected EOF, check daemon */
1654		} else if (rc == 1) {
1655			DPRINTF(2, ("daemon control: got '%c'\n",
1656				    (ch >= ' ' ? ch : '.')));
1657			if (ch == 'R' && !wait_sync)
1658				return 0;
1659			if (ch == 'S' && wait_sync)
1660				return 0;
1661		} else {
1662			DPRINTF(2, ("daemon control: read 1 char failed: %s\n",
1663				    strerror(errno)));
1664			return EX_IOERR;
1665		}
1666	} while (wait_rem > 0);
1667
1668	if (wait_sync) {
1669		fprintf(stderr, "%s: -w/--wait-sync %ld timed out.\n",
1670			progname, wait_sync);
1671		return EX_PROTOCOL;
1672	} else {
1673		fprintf(stderr, "%s: daemon startup monitoring timed out.\n",
1674			progname);
1675		return 0;
1676	}
1677}
1678
1679
1680static int
1681wait_child_exit_if(
1682	pid_t	cpid,
1683	int	blocking
1684	)
1685{
1686#    ifdef HAVE_WAITPID
1687	int	rc = 0;
1688	int	wstatus;
1689	if (cpid == waitpid(cpid, &wstatus, (blocking ? 0 : WNOHANG))) {
1690		DPRINTF(1, ("child (pid=%d) dead now\n", cpid));
1691		if (WIFEXITED(wstatus)) {
1692			rc = WEXITSTATUS(wstatus);
1693			msyslog(LOG_ERR, "daemon child exited with code %d",
1694				rc);
1695		} else if (WIFSIGNALED(wstatus)) {
1696			rc = EX_SOFTWARE;
1697			msyslog(LOG_ERR, "daemon child died with signal %d",
1698				WTERMSIG(wstatus));
1699		} else {
1700			rc = EX_SOFTWARE;
1701			msyslog(LOG_ERR, "daemon child died with unknown cause");
1702		}
1703	} else {
1704		DPRINTF(1, ("child (pid=%d) still alive\n", cpid));
1705	}
1706	return rc;
1707#    else
1708	UNUSED_ARG(cpid);
1709	return 0;
1710#    endif
1711}
1712
1713# endif	/* HAVE_WORKING_FORK */
1714
1715
1716/*
1717 * assertion_failed - Redirect assertion failures to msyslog().
1718 */
1719static void
1720assertion_failed(
1721	const char *file,
1722	int line,
1723	isc_assertiontype_t type,
1724	const char *cond
1725	)
1726{
1727	isc_assertion_setcallback(NULL);    /* Avoid recursion */
1728
1729	msyslog(LOG_ERR, "%s:%d: %s(%s) failed",
1730		file, line, isc_assertion_typetotext(type), cond);
1731	msyslog(LOG_ERR, "exiting (due to assertion failure)");
1732
1733#if defined(DEBUG) && defined(SYS_WINNT)
1734	if (debug)
1735		DebugBreak();
1736#endif
1737
1738	abort();
1739}
1740
1741
1742/*
1743 * library_fatal_error - Handle fatal errors from our libraries.
1744 */
1745static void
1746library_fatal_error(
1747	const char *file,
1748	int line,
1749	const char *format,
1750	va_list args
1751	)
1752{
1753	char errbuf[256];
1754
1755	isc_error_setfatal(NULL);  /* Avoid recursion */
1756
1757	msyslog(LOG_ERR, "%s:%d: fatal error:", file, line);
1758	vsnprintf(errbuf, sizeof(errbuf), format, args);
1759	msyslog(LOG_ERR, "%s", errbuf);
1760	msyslog(LOG_ERR, "exiting (due to fatal error in library)");
1761
1762#if defined(DEBUG) && defined(SYS_WINNT)
1763	if (debug)
1764		DebugBreak();
1765#endif
1766
1767	abort();
1768}
1769
1770
1771/*
1772 * library_unexpected_error - Handle non fatal errors from our libraries.
1773 */
1774# define MAX_UNEXPECTED_ERRORS 100
1775int unexpected_error_cnt = 0;
1776static void
1777library_unexpected_error(
1778	const char *file,
1779	int line,
1780	const char *format,
1781	va_list args
1782	)
1783{
1784	char errbuf[256];
1785
1786	if (unexpected_error_cnt >= MAX_UNEXPECTED_ERRORS)
1787		return;	/* avoid clutter in log */
1788
1789	msyslog(LOG_ERR, "%s:%d: unexpected error:", file, line);
1790	vsnprintf(errbuf, sizeof(errbuf), format, args);
1791	msyslog(LOG_ERR, "%s", errbuf);
1792
1793	if (++unexpected_error_cnt == MAX_UNEXPECTED_ERRORS)
1794		msyslog(LOG_ERR, "Too many errors.  Shutting up.");
1795
1796}
1797#endif	/* !SIM */
1798
1799#if !defined(SIM) && !defined(SYS_WINNT)
1800# ifdef DEBUG
1801
1802/*
1803 * moredebug - increase debugging verbosity
1804 */
1805static RETSIGTYPE
1806moredebug(
1807	int sig
1808	)
1809{
1810	int saved_errno = errno;
1811
1812	if (debug < 255)
1813	{
1814		debug++;
1815		msyslog(LOG_DEBUG, "debug raised to %d", debug);
1816	}
1817	errno = saved_errno;
1818}
1819
1820
1821/*
1822 * lessdebug - decrease debugging verbosity
1823 */
1824static RETSIGTYPE
1825lessdebug(
1826	int sig
1827	)
1828{
1829	int saved_errno = errno;
1830
1831	if (debug > 0)
1832	{
1833		debug--;
1834		msyslog(LOG_DEBUG, "debug lowered to %d", debug);
1835	}
1836	errno = saved_errno;
1837}
1838
1839# else	/* !DEBUG follows */
1840
1841
1842/*
1843 * no_debug - We don't do the debug here.
1844 */
1845static RETSIGTYPE
1846no_debug(
1847	int sig
1848	)
1849{
1850	int saved_errno = errno;
1851
1852	msyslog(LOG_DEBUG, "ntpd not compiled for debugging (signal %d)", sig);
1853	errno = saved_errno;
1854}
1855# endif	/* !DEBUG */
1856#endif	/* !SIM && !SYS_WINNT */
1857