xref: /freebsd/contrib/ntp/sntp/main.c (revision f3c5273d315a64826d2149ac453ff8c4583ddbe8)
1 #include <config.h>
2 
3 #include <event2/util.h>
4 #include <event2/event.h>
5 
6 #include "ntp_workimpl.h"
7 #ifdef WORK_THREAD
8 # include <event2/thread.h>
9 #endif
10 
11 #include "main.h"
12 #include "ntp_libopts.h"
13 #include "kod_management.h"
14 #include "networking.h"
15 #include "utilities.h"
16 #include "log.h"
17 #include "libntp.h"
18 
19 
20 int shutting_down;
21 int time_derived;
22 int time_adjusted;
23 int n_pending_dns = 0;
24 int n_pending_ntp = 0;
25 int ai_fam_pref = AF_UNSPEC;
26 int ntpver = 4;
27 double steplimit = -1;
28 SOCKET sock4 = -1;		/* Socket for IPv4 */
29 SOCKET sock6 = -1;		/* Socket for IPv6 */
30 /*
31 ** BCAST *must* listen on port 123 (by default), so we can only
32 ** use the UCST sockets (above) if they too are using port 123
33 */
34 SOCKET bsock4 = -1;		/* Broadcast Socket for IPv4 */
35 SOCKET bsock6 = -1;		/* Broadcast Socket for IPv6 */
36 struct event_base *base;
37 struct event *ev_sock4;
38 struct event *ev_sock6;
39 struct event *ev_worker_timeout;
40 struct event *ev_xmt_timer;
41 
42 struct dns_ctx {
43 	const char *	name;
44 	int		flags;
45 #define CTX_BCST	0x0001
46 #define CTX_UCST	0x0002
47 #define CTX_xCST	0x0003
48 #define CTX_CONC	0x0004
49 #define CTX_unused	0xfffd
50 	int		key_id;
51 	struct timeval	timeout;
52 	struct key *	key;
53 };
54 
55 typedef struct sent_pkt_tag sent_pkt;
56 struct sent_pkt_tag {
57 	sent_pkt *		link;
58 	struct dns_ctx *	dctx;
59 	sockaddr_u		addr;
60 	time_t			stime;
61 	int			done;
62 	struct pkt		x_pkt;
63 };
64 
65 typedef struct xmt_ctx_tag xmt_ctx;
66 struct xmt_ctx_tag {
67 	xmt_ctx *		link;
68 	SOCKET			sock;
69 	time_t			sched;
70 	sent_pkt *		spkt;
71 };
72 
73 struct timeval	gap;
74 xmt_ctx *	xmt_q;
75 struct key *	keys = NULL;
76 int		response_timeout;
77 struct timeval	response_tv;
78 struct timeval	start_tv;
79 /* check the timeout at least once per second */
80 struct timeval	wakeup_tv = { 0, 888888 };
81 
82 sent_pkt *	fam_listheads[2];
83 #define v4_pkts_list	(fam_listheads[0])
84 #define v6_pkts_list	(fam_listheads[1])
85 
86 static union {
87 	struct pkt pkt;
88 	char   buf[LEN_PKT_NOMAC + NTP_MAXEXTEN + MAX_MAC_LEN];
89 } rbuf;
90 
91 #define r_pkt  rbuf.pkt
92 
93 #ifdef HAVE_DROPROOT
94 int droproot;			/* intres imports these */
95 int root_dropped;
96 #endif
97 u_long current_time;		/* libntp/authkeys.c */
98 
99 void open_sockets(void);
100 void handle_lookup(const char *name, int flags);
101 void sntp_addremove_fd(int fd, int is_pipe, int remove_it);
102 void worker_timeout(evutil_socket_t, short, void *);
103 void worker_resp_cb(evutil_socket_t, short, void *);
104 void sntp_name_resolved(int, int, void *, const char *, const char *,
105 			const struct addrinfo *,
106 			const struct addrinfo *);
107 void queue_xmt(SOCKET sock, struct dns_ctx *dctx, sent_pkt *spkt,
108 	       u_int xmt_delay);
109 void xmt_timer_cb(evutil_socket_t, short, void *ptr);
110 void xmt(xmt_ctx *xctx);
111 int  check_kod(const struct addrinfo *ai);
112 void timeout_query(sent_pkt *);
113 void timeout_queries(void);
114 void sock_cb(evutil_socket_t, short, void *);
115 void check_exit_conditions(void);
116 void sntp_libevent_log_cb(int, const char *);
117 void set_li_vn_mode(struct pkt *spkt, char leap, char version, char mode);
118 int  set_time(double offset);
119 void dec_pending_ntp(const char *, sockaddr_u *);
120 int  libevent_version_ok(void);
121 int  gettimeofday_cached(struct event_base *b, struct timeval *tv);
122 
123 
124 /*
125  * The actual main function.
126  */
127 int
128 sntp_main (
129 	int argc,
130 	char **argv,
131 	const char *sntpVersion
132 	)
133 {
134 	int			i;
135 	int			exitcode;
136 	int			optct;
137 	struct event_config *	evcfg;
138 
139 	/* Initialize logging system - sets up progname */
140 	sntp_init_logging(argv[0]);
141 
142 	if (!libevent_version_ok())
143 		exit(EX_SOFTWARE);
144 
145 	init_lib();
146 	init_auth();
147 
148 	optct = ntpOptionProcess(&sntpOptions, argc, argv);
149 	argc -= optct;
150 	argv += optct;
151 
152 
153 	debug = OPT_VALUE_SET_DEBUG_LEVEL;
154 
155 	TRACE(2, ("init_lib() done, %s%s\n",
156 		  (ipv4_works)
157 		      ? "ipv4_works "
158 		      : "",
159 		  (ipv6_works)
160 		      ? "ipv6_works "
161 		      : ""));
162 	ntpver = OPT_VALUE_NTPVERSION;
163 	steplimit = OPT_VALUE_STEPLIMIT / 1e3;
164 	gap.tv_usec = max(0, OPT_VALUE_GAP * 1000);
165 	gap.tv_usec = min(gap.tv_usec, 999999);
166 
167 	if (HAVE_OPT(LOGFILE))
168 		open_logfile(OPT_ARG(LOGFILE));
169 
170 	msyslog(LOG_INFO, "%s", sntpVersion);
171 
172 	if (0 == argc && !HAVE_OPT(BROADCAST) && !HAVE_OPT(CONCURRENT)) {
173 		printf("%s: Must supply at least one of -b hostname, -c hostname, or hostname.\n",
174 		       progname);
175 		exit(EX_USAGE);
176 	}
177 
178 
179 	/*
180 	** Eventually, we probably want:
181 	** - separate bcst and ucst timeouts (why?)
182 	** - multiple --timeout values in the commandline
183 	*/
184 
185 	response_timeout = OPT_VALUE_TIMEOUT;
186 	response_tv.tv_sec = response_timeout;
187 	response_tv.tv_usec = 0;
188 
189 	/* IPv6 available? */
190 	if (isc_net_probeipv6() != ISC_R_SUCCESS) {
191 		ai_fam_pref = AF_INET;
192 		TRACE(1, ("No ipv6 support available, forcing ipv4\n"));
193 	} else {
194 		/* Check for options -4 and -6 */
195 		if (HAVE_OPT(IPV4))
196 			ai_fam_pref = AF_INET;
197 		else if (HAVE_OPT(IPV6))
198 			ai_fam_pref = AF_INET6;
199 	}
200 
201 	/* TODO: Parse config file if declared */
202 
203 	/*
204 	** Init the KOD system.
205 	** For embedded systems with no writable filesystem,
206 	** -K /dev/null can be used to disable KoD storage.
207 	*/
208 	kod_init_kod_db(OPT_ARG(KOD), FALSE);
209 
210 	/* HMS: Check and see what happens if KEYFILE doesn't exist */
211 	auth_init(OPT_ARG(KEYFILE), &keys);
212 
213 	/*
214 	** Considering employing a variable that prevents functions of doing
215 	** anything until everything is initialized properly
216 	**
217 	** HMS: What exactly does the above mean?
218 	*/
219 	event_set_log_callback(&sntp_libevent_log_cb);
220 	if (debug > 0)
221 		event_enable_debug_mode();
222 #ifdef WORK_THREAD
223 	evthread_use_pthreads();
224 	/* we use libevent from main thread only, locks should be academic */
225 	if (debug > 0)
226 		evthread_enable_lock_debuging();
227 #endif
228 	evcfg = event_config_new();
229 	if (NULL == evcfg) {
230 		printf("%s: event_config_new() failed!\n", progname);
231 		return -1;
232 	}
233 #ifndef HAVE_SOCKETPAIR
234 	event_config_require_features(evcfg, EV_FEATURE_FDS);
235 #endif
236 	/* all libevent calls are from main thread */
237 	/* event_config_set_flag(evcfg, EVENT_BASE_FLAG_NOLOCK); */
238 	base = event_base_new_with_config(evcfg);
239 	event_config_free(evcfg);
240 	if (NULL == base) {
241 		printf("%s: event_base_new() failed!\n", progname);
242 		return -1;
243 	}
244 
245 	/* wire into intres resolver */
246 	worker_per_query = TRUE;
247 	addremove_io_fd = &sntp_addremove_fd;
248 
249 	open_sockets();
250 
251 	if (HAVE_OPT(BROADCAST)) {
252 		int		cn = STACKCT_OPT(  BROADCAST );
253 		const char **	cp = STACKLST_OPT( BROADCAST );
254 
255 		while (cn-- > 0) {
256 			handle_lookup(*cp, CTX_BCST);
257 			cp++;
258 		}
259 	}
260 
261 	if (HAVE_OPT(CONCURRENT)) {
262 		int		cn = STACKCT_OPT( CONCURRENT );
263 		const char **	cp = STACKLST_OPT( CONCURRENT );
264 
265 		while (cn-- > 0) {
266 			handle_lookup(*cp, CTX_UCST | CTX_CONC);
267 			cp++;
268 		}
269 	}
270 
271 	for (i = 0; i < argc; ++i)
272 		handle_lookup(argv[i], CTX_UCST);
273 
274 	gettimeofday_cached(base, &start_tv);
275 	event_base_dispatch(base);
276 	event_base_free(base);
277 
278 	if (!time_adjusted &&
279 	    (ENABLED_OPT(STEP) || ENABLED_OPT(SLEW)))
280 		exitcode = 1;
281 	else
282 		exitcode = 0;
283 
284 	return exitcode;
285 }
286 
287 
288 /*
289 ** open sockets and make them non-blocking
290 */
291 void
292 open_sockets(
293 	void
294 	)
295 {
296 	sockaddr_u	name;
297 
298 	if (-1 == sock4) {
299 		sock4 = socket(PF_INET, SOCK_DGRAM, 0);
300 		if (-1 == sock4) {
301 			/* error getting a socket */
302 			msyslog(LOG_ERR, "open_sockets: socket(PF_INET) failed: %m");
303 			exit(1);
304 		}
305 		/* Make it non-blocking */
306 		make_socket_nonblocking(sock4);
307 
308 		/* Let's try using a wildcard... */
309 		ZERO(name);
310 		AF(&name) = AF_INET;
311 		SET_ADDR4N(&name, INADDR_ANY);
312 		SET_PORT(&name, (HAVE_OPT(USERESERVEDPORT) ? 123 : 0));
313 
314 		if (-1 == bind(sock4, &name.sa,
315 			       SOCKLEN(&name))) {
316 			msyslog(LOG_ERR, "open_sockets: bind(sock4) failed: %m");
317 			exit(1);
318 		}
319 
320 		/* Register an NTP callback for recv/timeout */
321 		ev_sock4 = event_new(base, sock4,
322 				     EV_TIMEOUT | EV_READ | EV_PERSIST,
323 				     &sock_cb, NULL);
324 		if (NULL == ev_sock4) {
325 			msyslog(LOG_ERR,
326 				"open_sockets: event_new(base, sock4) failed!");
327 		} else {
328 			event_add(ev_sock4, &wakeup_tv);
329 		}
330 	}
331 
332 	/* We may not always have IPv6... */
333 	if (-1 == sock6 && ipv6_works) {
334 		sock6 = socket(PF_INET6, SOCK_DGRAM, 0);
335 		if (-1 == sock6 && ipv6_works) {
336 			/* error getting a socket */
337 			msyslog(LOG_ERR, "open_sockets: socket(PF_INET6) failed: %m");
338 			exit(1);
339 		}
340 		/* Make it non-blocking */
341 		make_socket_nonblocking(sock6);
342 
343 		/* Let's try using a wildcard... */
344 		ZERO(name);
345 		AF(&name) = AF_INET6;
346 		SET_ADDR6N(&name, in6addr_any);
347 		SET_PORT(&name, (HAVE_OPT(USERESERVEDPORT) ? 123 : 0));
348 
349 		if (-1 == bind(sock6, &name.sa,
350 			       SOCKLEN(&name))) {
351 			msyslog(LOG_ERR, "open_sockets: bind(sock6) failed: %m");
352 			exit(1);
353 		}
354 		/* Register an NTP callback for recv/timeout */
355 		ev_sock6 = event_new(base, sock6,
356 				     EV_TIMEOUT | EV_READ | EV_PERSIST,
357 				     &sock_cb, NULL);
358 		if (NULL == ev_sock6) {
359 			msyslog(LOG_ERR,
360 				"open_sockets: event_new(base, sock6) failed!");
361 		} else {
362 			event_add(ev_sock6, &wakeup_tv);
363 		}
364 	}
365 
366 	return;
367 }
368 
369 
370 /*
371 ** handle_lookup
372 */
373 void
374 handle_lookup(
375 	const char *name,
376 	int flags
377 	)
378 {
379 	struct addrinfo	hints;	/* Local copy is OK */
380 	struct dns_ctx *ctx;
381 	char *		name_copy;
382 	size_t		name_sz;
383 	size_t		octets;
384 
385 	TRACE(1, ("handle_lookup(%s,%#x)\n", name, flags));
386 
387 	ZERO(hints);
388 	hints.ai_family = ai_fam_pref;
389 	hints.ai_flags = AI_CANONNAME | Z_AI_NUMERICSERV;
390 	/*
391 	** Unless we specify a socktype, we'll get at least two
392 	** entries for each address: one for TCP and one for
393 	** UDP. That's not what we want.
394 	*/
395 	hints.ai_socktype = SOCK_DGRAM;
396 	hints.ai_protocol = IPPROTO_UDP;
397 
398 	name_sz = 1 + strlen(name);
399 	octets = sizeof(*ctx) + name_sz;	// Space for a ctx and the name
400 	ctx = emalloc_zero(octets);		// ctx at ctx[0]
401 	name_copy = (char *)(ctx + 1);		// Put the name at ctx[1]
402 	memcpy(name_copy, name, name_sz);	// copy the name to ctx[1]
403 	ctx->name = name_copy;			// point to it...
404 	ctx->flags = flags;
405 	ctx->timeout = response_tv;
406 	ctx->key = NULL;
407 
408 	/* The following should arguably be passed in... */
409 	if (ENABLED_OPT(AUTHENTICATION)) {
410 		ctx->key_id = OPT_VALUE_AUTHENTICATION;
411 		get_key(ctx->key_id, &ctx->key);
412 		if (NULL == ctx->key) {
413 			fprintf(stderr, "%s: Authentication with keyID %d requested, but no matching keyID found in <%s>!\n",
414 				progname, ctx->key_id, OPT_ARG(KEYFILE));
415 			exit(1);
416 		}
417 	} else {
418 		ctx->key_id = -1;
419 	}
420 
421 	++n_pending_dns;
422 	getaddrinfo_sometime(name, "123", &hints, 0,
423 			     &sntp_name_resolved, ctx);
424 }
425 
426 
427 /*
428 ** DNS Callback:
429 ** - For each IP:
430 ** - - open a socket
431 ** - - increment n_pending_ntp
432 ** - - send a request if this is a Unicast callback
433 ** - - queue wait for response
434 ** - decrement n_pending_dns
435 */
436 void
437 sntp_name_resolved(
438 	int			rescode,
439 	int			gai_errno,
440 	void *			context,
441 	const char *		name,
442 	const char *		service,
443 	const struct addrinfo *	hints,
444 	const struct addrinfo *	addr
445 	)
446 {
447 	struct dns_ctx *	dctx;
448 	sent_pkt *		spkt;
449 	const struct addrinfo *	ai;
450 	SOCKET			sock;
451 	u_int			xmt_delay_v4;
452 	u_int			xmt_delay_v6;
453 	u_int			xmt_delay;
454 	size_t			octets;
455 
456 	xmt_delay_v4 = 0;
457 	xmt_delay_v6 = 0;
458 	dctx = context;
459 	if (rescode) {
460 #ifdef EAI_SYSTEM
461 		if (EAI_SYSTEM == rescode) {
462 			errno = gai_errno;
463 			mfprintf(stderr, "%s lookup error %m\n",
464 				 dctx->name);
465 		} else
466 #endif
467 			fprintf(stderr, "%s lookup error %s\n",
468 				dctx->name, gai_strerror(rescode));
469 	} else {
470 		TRACE(3, ("%s [%s]\n", dctx->name,
471 			  (addr->ai_canonname != NULL)
472 			      ? addr->ai_canonname
473 			      : ""));
474 
475 		for (ai = addr; ai != NULL; ai = ai->ai_next) {
476 
477 			if (check_kod(ai))
478 				continue;
479 
480 			switch (ai->ai_family) {
481 
482 			case AF_INET:
483 				sock = sock4;
484 				xmt_delay = xmt_delay_v4;
485 				xmt_delay_v4++;
486 				break;
487 
488 			case AF_INET6:
489 				if (!ipv6_works)
490 					continue;
491 
492 				sock = sock6;
493 				xmt_delay = xmt_delay_v6;
494 				xmt_delay_v6++;
495 				break;
496 
497 			default:
498 				msyslog(LOG_ERR, "sntp_name_resolved: unexpected ai_family: %d",
499 					ai->ai_family);
500 				exit(1);
501 				break;
502 			}
503 
504 			/*
505 			** We're waiting for a response for either unicast
506 			** or broadcast, so...
507 			*/
508 			++n_pending_ntp;
509 
510 			/* If this is for a unicast IP, queue a request */
511 			if (dctx->flags & CTX_UCST) {
512 				spkt = emalloc_zero(sizeof(*spkt));
513 				spkt->dctx = dctx;
514 				octets = min(ai->ai_addrlen, sizeof(spkt->addr));
515 				memcpy(&spkt->addr, ai->ai_addr, octets);
516 				queue_xmt(sock, dctx, spkt, xmt_delay);
517 			}
518 		}
519 	}
520 	/* n_pending_dns really should be >0 here... */
521 	--n_pending_dns;
522 	check_exit_conditions();
523 }
524 
525 
526 /*
527 ** queue_xmt
528 */
529 void
530 queue_xmt(
531 	SOCKET			sock,
532 	struct dns_ctx *	dctx,
533 	sent_pkt *		spkt,
534 	u_int			xmt_delay
535 	)
536 {
537 	sockaddr_u *	dest;
538 	sent_pkt **	pkt_listp;
539 	sent_pkt *	match;
540 	xmt_ctx *	xctx;
541 	struct timeval	start_cb;
542 	struct timeval	delay;
543 
544 	dest = &spkt->addr;
545 	if (IS_IPV6(dest))
546 		pkt_listp = &v6_pkts_list;
547 	else
548 		pkt_listp = &v4_pkts_list;
549 
550 	/* reject attempts to add address already listed */
551 	for (match = *pkt_listp; match != NULL; match = match->link) {
552 		if (ADDR_PORT_EQ(&spkt->addr, &match->addr)) {
553 			if (strcasecmp(spkt->dctx->name,
554 				       match->dctx->name))
555 				printf("%s %s duplicate address from %s ignored.\n",
556 				       sptoa(&match->addr),
557 				       match->dctx->name,
558 				       spkt->dctx->name);
559 			else
560 				printf("%s %s, duplicate address ignored.\n",
561 				       sptoa(&match->addr),
562 				       match->dctx->name);
563 			dec_pending_ntp(spkt->dctx->name, &spkt->addr);
564 			free(spkt);
565 			return;
566 		}
567 	}
568 
569 	LINK_SLIST(*pkt_listp, spkt, link);
570 
571 	xctx = emalloc_zero(sizeof(*xctx));
572 	xctx->sock = sock;
573 	xctx->spkt = spkt;
574 	gettimeofday_cached(base, &start_cb);
575 	xctx->sched = start_cb.tv_sec + (2 * xmt_delay);
576 
577 	LINK_SORT_SLIST(xmt_q, xctx, (xctx->sched < L_S_S_CUR()->sched),
578 			link, xmt_ctx);
579 	if (xmt_q == xctx) {
580 		/*
581 		 * The new entry is the first scheduled.  The timer is
582 		 * either not active or is set for the second xmt
583 		 * context in xmt_q.
584 		 */
585 		if (NULL == ev_xmt_timer)
586 			ev_xmt_timer = event_new(base, INVALID_SOCKET,
587 						 EV_TIMEOUT,
588 						 &xmt_timer_cb, NULL);
589 		if (NULL == ev_xmt_timer) {
590 			msyslog(LOG_ERR,
591 				"queue_xmt: event_new(base, -1, EV_TIMEOUT) failed!");
592 			exit(1);
593 		}
594 		ZERO(delay);
595 		if (xctx->sched > start_cb.tv_sec)
596 			delay.tv_sec = xctx->sched - start_cb.tv_sec;
597 		event_add(ev_xmt_timer, &delay);
598 		TRACE(2, ("queue_xmt: xmt timer for %u usec\n",
599 			  (u_int)delay.tv_usec));
600 	}
601 }
602 
603 
604 /*
605 ** xmt_timer_cb
606 */
607 void
608 xmt_timer_cb(
609 	evutil_socket_t	fd,
610 	short		what,
611 	void *		ctx
612 	)
613 {
614 	struct timeval	start_cb;
615 	struct timeval	delay;
616 	xmt_ctx *	x;
617 
618 	UNUSED_ARG(fd);
619 	UNUSED_ARG(ctx);
620 	DEBUG_INSIST(EV_TIMEOUT == what);
621 
622 	if (NULL == xmt_q || shutting_down)
623 		return;
624 	gettimeofday_cached(base, &start_cb);
625 	if (xmt_q->sched <= start_cb.tv_sec) {
626 		UNLINK_HEAD_SLIST(x, xmt_q, link);
627 		TRACE(2, ("xmt_timer_cb: at .%6.6u -> %s\n",
628 			  (u_int)start_cb.tv_usec, stoa(&x->spkt->addr)));
629 		xmt(x);
630 		free(x);
631 		if (NULL == xmt_q)
632 			return;
633 	}
634 	if (xmt_q->sched <= start_cb.tv_sec) {
635 		event_add(ev_xmt_timer, &gap);
636 		TRACE(2, ("xmt_timer_cb: at .%6.6u gap %6.6u\n",
637 			  (u_int)start_cb.tv_usec,
638 			  (u_int)gap.tv_usec));
639 	} else {
640 		delay.tv_sec = xmt_q->sched - start_cb.tv_sec;
641 		delay.tv_usec = 0;
642 		event_add(ev_xmt_timer, &delay);
643 		TRACE(2, ("xmt_timer_cb: at .%6.6u next %ld seconds\n",
644 			  (u_int)start_cb.tv_usec,
645 			  (long)delay.tv_sec));
646 	}
647 }
648 
649 
650 /*
651 ** xmt()
652 */
653 void
654 xmt(
655 	xmt_ctx *	xctx
656 	)
657 {
658 	SOCKET		sock = xctx->sock;
659 	struct dns_ctx *dctx = xctx->spkt->dctx;
660 	sent_pkt *	spkt = xctx->spkt;
661 	sockaddr_u *	dst = &spkt->addr;
662 	struct timeval	tv_xmt;
663 	struct pkt	x_pkt;
664 	size_t		pkt_len;
665 	int		sent;
666 
667 	if (0 != gettimeofday(&tv_xmt, NULL)) {
668 		msyslog(LOG_ERR,
669 			"xmt: gettimeofday() failed: %m");
670 		exit(1);
671 	}
672 	tv_xmt.tv_sec += JAN_1970;
673 
674 	pkt_len = generate_pkt(&x_pkt, &tv_xmt, dctx->key_id,
675 			       dctx->key);
676 
677 	sent = sendpkt(sock, dst, &x_pkt, pkt_len);
678 	if (sent) {
679 		/* Save the packet we sent... */
680 		memcpy(&spkt->x_pkt, &x_pkt, min(sizeof(spkt->x_pkt),
681 		       pkt_len));
682 		spkt->stime = tv_xmt.tv_sec - JAN_1970;
683 
684 		TRACE(2, ("xmt: %lx.%6.6u %s %s\n", (u_long)tv_xmt.tv_sec,
685 			  (u_int)tv_xmt.tv_usec, dctx->name, stoa(dst)));
686 	} else {
687 		dec_pending_ntp(dctx->name, dst);
688 	}
689 
690 	return;
691 }
692 
693 
694 /*
695  * timeout_queries() -- give up on unrequited NTP queries
696  */
697 void
698 timeout_queries(void)
699 {
700 	struct timeval	start_cb;
701 	u_int		idx;
702 	sent_pkt *	head;
703 	sent_pkt *	spkt;
704 	sent_pkt *	spkt_next;
705 	long		age;
706 	int didsomething = 0;
707 
708 	TRACE(3, ("timeout_queries: called to check %u items\n",
709 		  (unsigned)COUNTOF(fam_listheads)));
710 
711 	gettimeofday_cached(base, &start_cb);
712 	for (idx = 0; idx < COUNTOF(fam_listheads); idx++) {
713 		head = fam_listheads[idx];
714 		for (spkt = head; spkt != NULL; spkt = spkt_next) {
715 			char xcst;
716 
717 			didsomething = 1;
718 			switch (spkt->dctx->flags & CTX_xCST) {
719 			    case CTX_BCST:
720 				xcst = 'B';
721 				break;
722 
723 			    case CTX_UCST:
724 				xcst = 'U';
725 				break;
726 
727 			    default:
728 				INSIST(!"spkt->dctx->flags neither UCST nor BCST");
729 				break;
730 			}
731 
732 			spkt_next = spkt->link;
733 			if (0 == spkt->stime || spkt->done)
734 				continue;
735 			age = start_cb.tv_sec - spkt->stime;
736 			TRACE(3, ("%s %s %cCST age %ld\n",
737 				  stoa(&spkt->addr),
738 				  spkt->dctx->name, xcst, age));
739 			if (age > response_timeout)
740 				timeout_query(spkt);
741 		}
742 	}
743 	// Do we care about didsomething?
744 	TRACE(3, ("timeout_queries: didsomething is %d, age is %ld\n",
745 		  didsomething, (long) (start_cb.tv_sec - start_tv.tv_sec)));
746 	if (start_cb.tv_sec - start_tv.tv_sec > response_timeout) {
747 		TRACE(3, ("timeout_queries: bail!\n"));
748 		event_base_loopexit(base, NULL);
749 		shutting_down = TRUE;
750 	}
751 }
752 
753 
754 void dec_pending_ntp(
755 	const char *	name,
756 	sockaddr_u *	server
757 	)
758 {
759 	if (n_pending_ntp > 0) {
760 		--n_pending_ntp;
761 		check_exit_conditions();
762 	} else {
763 		INSIST(0 == n_pending_ntp);
764 		TRACE(1, ("n_pending_ntp was zero before decrement for %s\n",
765 			  hostnameaddr(name, server)));
766 	}
767 }
768 
769 
770 void timeout_query(
771 	sent_pkt *	spkt
772 	)
773 {
774 	sockaddr_u *	server;
775 	char		xcst;
776 
777 
778 	switch (spkt->dctx->flags & CTX_xCST) {
779 	    case CTX_BCST:
780 		xcst = 'B';
781 		break;
782 
783 	    case CTX_UCST:
784 		xcst = 'U';
785 		break;
786 
787 	    default:
788 		INSIST(!"spkt->dctx->flags neither UCST nor BCST");
789 		break;
790 	}
791 	spkt->done = TRUE;
792 	server = &spkt->addr;
793 	msyslog(LOG_INFO, "%s no %cCST response after %d seconds",
794 		hostnameaddr(spkt->dctx->name, server), xcst,
795 		response_timeout);
796 	dec_pending_ntp(spkt->dctx->name, server);
797 	return;
798 }
799 
800 
801 /*
802 ** check_kod
803 */
804 int
805 check_kod(
806 	const struct addrinfo *	ai
807 	)
808 {
809 	char *hostname;
810 	struct kod_entry *reason;
811 
812 	/* Is there a KoD on file for this address? */
813 	hostname = addrinfo_to_str(ai);
814 	TRACE(2, ("check_kod: checking <%s>\n", hostname));
815 	if (search_entry(hostname, &reason)) {
816 		printf("prior KoD for %s, skipping.\n",
817 			hostname);
818 		free(reason);
819 		free(hostname);
820 
821 		return 1;
822 	}
823 	free(hostname);
824 
825 	return 0;
826 }
827 
828 
829 /*
830 ** Socket readable/timeout Callback:
831 ** Read in the packet
832 ** Unicast:
833 ** - close socket
834 ** - decrement n_pending_ntp
835 ** - If packet is good, set the time and "exit"
836 ** Broadcast:
837 ** - If packet is good, set the time and "exit"
838 */
839 void
840 sock_cb(
841 	evutil_socket_t fd,
842 	short what,
843 	void *ptr
844 	)
845 {
846 	sockaddr_u	sender;
847 	sockaddr_u *	psau;
848 	sent_pkt **	p_pktlist;
849 	sent_pkt *	spkt;
850 	int		rpktl;
851 	int		rc;
852 
853 	INSIST(sock4 == fd || sock6 == fd);
854 
855 	TRACE(3, ("sock_cb: event on sock%s:%s%s%s%s\n",
856 		  (fd == sock6)
857 		      ? "6"
858 		      : "4",
859 		  (what & EV_TIMEOUT) ? " timeout" : "",
860 		  (what & EV_READ)    ? " read" : "",
861 		  (what & EV_WRITE)   ? " write" : "",
862 		  (what & EV_SIGNAL)  ? " signal" : ""));
863 
864 	if (!(EV_READ & what)) {
865 		if (EV_TIMEOUT & what)
866 			timeout_queries();
867 
868 		return;
869 	}
870 
871 	/* Read in the packet */
872 	rpktl = recvdata(fd, &sender, &rbuf, sizeof(rbuf));
873 	if (rpktl < 0) {
874 		msyslog(LOG_DEBUG, "recvfrom error %m");
875 		return;
876 	}
877 
878 	if (sock6 == fd)
879 		p_pktlist = &v6_pkts_list;
880 	else
881 		p_pktlist = &v4_pkts_list;
882 
883 	for (spkt = *p_pktlist; spkt != NULL; spkt = spkt->link) {
884 		psau = &spkt->addr;
885 		if (SOCK_EQ(&sender, psau))
886 			break;
887 	}
888 	if (NULL == spkt) {
889 		msyslog(LOG_WARNING,
890 			"Packet from unexpected source %s dropped",
891 			sptoa(&sender));
892 		return;
893 	}
894 
895 	TRACE(1, ("sock_cb: %s %s\n", spkt->dctx->name,
896 		  sptoa(&sender)));
897 
898 	rpktl = process_pkt(&r_pkt, &sender, rpktl, MODE_SERVER,
899 			    &spkt->x_pkt, "sock_cb");
900 
901 	TRACE(2, ("sock_cb: process_pkt returned %d\n", rpktl));
902 
903 	/* If this is a Unicast packet, one down ... */
904 	if (!spkt->done && (CTX_UCST & spkt->dctx->flags)) {
905 		dec_pending_ntp(spkt->dctx->name, &spkt->addr);
906 		spkt->done = TRUE;
907 	}
908 
909 
910 	/* If the packet is good, set the time and we're all done */
911 	rc = handle_pkt(rpktl, &r_pkt, &spkt->addr, spkt->dctx->name);
912 	if (0 != rc)
913 		TRACE(1, ("sock_cb: handle_pkt() returned %d\n", rc));
914 	check_exit_conditions();
915 }
916 
917 
918 /*
919  * check_exit_conditions()
920  *
921  * If sntp has a reply, ask the event loop to stop after this round of
922  * callbacks, unless --wait was used.
923  */
924 void
925 check_exit_conditions(void)
926 {
927 	if ((0 == n_pending_ntp && 0 == n_pending_dns) ||
928 	    (time_derived && !HAVE_OPT(WAIT))) {
929 		event_base_loopexit(base, NULL);
930 		shutting_down = TRUE;
931 	} else {
932 		TRACE(2, ("%d NTP and %d name queries pending\n",
933 			  n_pending_ntp, n_pending_dns));
934 	}
935 }
936 
937 
938 /*
939  * sntp_addremove_fd() is invoked by the intres blocking worker code
940  * to read from a pipe, or to stop same.
941  */
942 void sntp_addremove_fd(
943 	int	fd,
944 	int	is_pipe,
945 	int	remove_it
946 	)
947 {
948 	u_int		idx;
949 	blocking_child *c;
950 	struct event *	ev;
951 
952 #ifdef HAVE_SOCKETPAIR
953 	if (is_pipe) {
954 		/* sntp only asks for EV_FEATURE_FDS without HAVE_SOCKETPAIR */
955 		msyslog(LOG_ERR, "fatal: pipes not supported on systems with socketpair()");
956 		exit(1);
957 	}
958 #endif
959 
960 	c = NULL;
961 	for (idx = 0; idx < blocking_children_alloc; idx++) {
962 		c = blocking_children[idx];
963 		if (NULL == c)
964 			continue;
965 		if (fd == c->resp_read_pipe)
966 			break;
967 	}
968 	if (idx == blocking_children_alloc)
969 		return;
970 
971 	if (remove_it) {
972 		ev = c->resp_read_ctx;
973 		c->resp_read_ctx = NULL;
974 		event_del(ev);
975 		event_free(ev);
976 
977 		return;
978 	}
979 
980 	ev = event_new(base, fd, EV_READ | EV_PERSIST,
981 		       &worker_resp_cb, c);
982 	if (NULL == ev) {
983 		msyslog(LOG_ERR,
984 			"sntp_addremove_fd: event_new(base, fd) failed!");
985 		return;
986 	}
987 	c->resp_read_ctx = ev;
988 	event_add(ev, NULL);
989 }
990 
991 
992 /* called by forked intres child to close open descriptors */
993 #ifdef WORK_FORK
994 void
995 kill_asyncio(
996 	int	startfd
997 	)
998 {
999 	if (INVALID_SOCKET != sock4) {
1000 		closesocket(sock4);
1001 		sock4 = INVALID_SOCKET;
1002 	}
1003 	if (INVALID_SOCKET != sock6) {
1004 		closesocket(sock6);
1005 		sock6 = INVALID_SOCKET;
1006 	}
1007 	if (INVALID_SOCKET != bsock4) {
1008 		closesocket(sock4);
1009 		sock4 = INVALID_SOCKET;
1010 	}
1011 	if (INVALID_SOCKET != bsock6) {
1012 		closesocket(sock6);
1013 		sock6 = INVALID_SOCKET;
1014 	}
1015 }
1016 #endif
1017 
1018 
1019 /*
1020  * worker_resp_cb() is invoked when resp_read_pipe is readable.
1021  */
1022 void
1023 worker_resp_cb(
1024 	evutil_socket_t	fd,
1025 	short		what,
1026 	void *		ctx	/* blocking_child * */
1027 	)
1028 {
1029 	blocking_child *	c;
1030 
1031 	DEBUG_INSIST(EV_READ & what);
1032 	c = ctx;
1033 	DEBUG_INSIST(fd == c->resp_read_pipe);
1034 	process_blocking_resp(c);
1035 }
1036 
1037 
1038 /*
1039  * intres_timeout_req(s) is invoked in the parent to schedule an idle
1040  * timeout to fire in s seconds, if not reset earlier by a call to
1041  * intres_timeout_req(0), which clears any pending timeout.  When the
1042  * timeout expires, worker_idle_timer_fired() is invoked (again, in the
1043  * parent).
1044  *
1045  * sntp and ntpd each provide implementations adapted to their timers.
1046  */
1047 void
1048 intres_timeout_req(
1049 	u_int	seconds		/* 0 cancels */
1050 	)
1051 {
1052 	struct timeval	tv_to;
1053 
1054 	if (NULL == ev_worker_timeout) {
1055 		ev_worker_timeout = event_new(base, -1,
1056 					      EV_TIMEOUT | EV_PERSIST,
1057 					      &worker_timeout, NULL);
1058 		DEBUG_INSIST(NULL != ev_worker_timeout);
1059 	} else {
1060 		event_del(ev_worker_timeout);
1061 	}
1062 	if (0 == seconds)
1063 		return;
1064 	tv_to.tv_sec = seconds;
1065 	tv_to.tv_usec = 0;
1066 	event_add(ev_worker_timeout, &tv_to);
1067 }
1068 
1069 
1070 void
1071 worker_timeout(
1072 	evutil_socket_t	fd,
1073 	short		what,
1074 	void *		ctx
1075 	)
1076 {
1077 	UNUSED_ARG(fd);
1078 	UNUSED_ARG(ctx);
1079 
1080 	DEBUG_REQUIRE(EV_TIMEOUT & what);
1081 	worker_idle_timer_fired();
1082 }
1083 
1084 
1085 void
1086 sntp_libevent_log_cb(
1087 	int		severity,
1088 	const char *	msg
1089 	)
1090 {
1091 	int		level;
1092 
1093 	switch (severity) {
1094 
1095 	default:
1096 	case _EVENT_LOG_DEBUG:
1097 		level = LOG_DEBUG;
1098 		break;
1099 
1100 	case _EVENT_LOG_MSG:
1101 		level = LOG_NOTICE;
1102 		break;
1103 
1104 	case _EVENT_LOG_WARN:
1105 		level = LOG_WARNING;
1106 		break;
1107 
1108 	case _EVENT_LOG_ERR:
1109 		level = LOG_ERR;
1110 		break;
1111 	}
1112 
1113 	msyslog(level, "%s", msg);
1114 }
1115 
1116 
1117 int
1118 generate_pkt (
1119 	struct pkt *x_pkt,
1120 	const struct timeval *tv_xmt,
1121 	int key_id,
1122 	struct key *pkt_key
1123 	)
1124 {
1125 	l_fp	xmt_fp;
1126 	int	pkt_len;
1127 	int	mac_size;
1128 
1129 	pkt_len = LEN_PKT_NOMAC;
1130 	ZERO(*x_pkt);
1131 	TVTOTS(tv_xmt, &xmt_fp);
1132 	HTONL_FP(&xmt_fp, &x_pkt->xmt);
1133 	x_pkt->stratum = STRATUM_TO_PKT(STRATUM_UNSPEC);
1134 	x_pkt->ppoll = 8;
1135 	/* FIXME! Modus broadcast + adr. check -> bdr. pkt */
1136 	set_li_vn_mode(x_pkt, LEAP_NOTINSYNC, ntpver, 3);
1137 	if (debug > 0) {
1138 		printf("generate_pkt: key_id %d, key pointer %p\n", key_id, pkt_key);
1139 	}
1140 	if (pkt_key != NULL) {
1141 		x_pkt->exten[0] = htonl(key_id);
1142 		mac_size = make_mac(x_pkt, pkt_len, MAX_MDG_LEN,
1143 				    pkt_key, (char *)&x_pkt->exten[1]);
1144 		if (mac_size > 0)
1145 			pkt_len += mac_size + KEY_MAC_LEN;
1146 #ifdef DEBUG
1147 		if (debug > 0) {
1148 			printf("generate_pkt: mac_size is %d\n", mac_size);
1149 		}
1150 #endif
1151 
1152 	}
1153 	return pkt_len;
1154 }
1155 
1156 
1157 int
1158 handle_pkt(
1159 	int		rpktl,
1160 	struct pkt *	rpkt,
1161 	sockaddr_u *	host,
1162 	const char *	hostname
1163 	)
1164 {
1165 	char		disptxt[32];
1166 	const char *	addrtxt;
1167 	struct timeval	tv_dst;
1168 	int		cnt;
1169 	int		sw_case;
1170 	int		digits;
1171 	int		stratum;
1172 	char *		ref;
1173 	char *		ts_str;
1174 	const char *	leaptxt;
1175 	double		offset;
1176 	double		precision;
1177 	double		synch_distance;
1178 	char *		p_SNTP_PRETEND_TIME;
1179 	time_t		pretend_time;
1180 #if SIZEOF_TIME_T == 8
1181 	long long	ll;
1182 #else
1183 	long		l;
1184 #endif
1185 
1186 	ts_str = NULL;
1187 
1188 	if (rpktl > 0)
1189 		sw_case = 1;
1190 	else
1191 		sw_case = rpktl;
1192 
1193 	switch (sw_case) {
1194 
1195 	case SERVER_UNUSEABLE:
1196 		return -1;
1197 		break;
1198 
1199 	case PACKET_UNUSEABLE:
1200 		break;
1201 
1202 	case SERVER_AUTH_FAIL:
1203 		break;
1204 
1205 	case KOD_DEMOBILIZE:
1206 		/* Received a DENY or RESTR KOD packet */
1207 		addrtxt = stoa(host);
1208 		ref = (char *)&rpkt->refid;
1209 		add_entry(addrtxt, ref);
1210 		msyslog(LOG_WARNING, "KOD code %c%c%c%c from %s %s",
1211 			ref[0], ref[1], ref[2], ref[3], addrtxt, hostname);
1212 		break;
1213 
1214 	case KOD_RATE:
1215 		/*
1216 		** Hmm...
1217 		** We should probably call add_entry() with an
1218 		** expiration timestamp of several seconds in the future,
1219 		** and back-off even more if we get more RATE responses.
1220 		*/
1221 		break;
1222 
1223 	case 1:
1224 		TRACE(3, ("handle_pkt: %d bytes from %s %s\n",
1225 			  rpktl, stoa(host), hostname));
1226 
1227 		gettimeofday_cached(base, &tv_dst);
1228 
1229 		p_SNTP_PRETEND_TIME = getenv("SNTP_PRETEND_TIME");
1230 		if (p_SNTP_PRETEND_TIME) {
1231 			pretend_time = 0;
1232 #if SIZEOF_TIME_T == 4
1233 			if (1 == sscanf(p_SNTP_PRETEND_TIME, "%ld", &l))
1234 				pretend_time = (time_t)l;
1235 #elif SIZEOF_TIME_T == 8
1236 			if (1 == sscanf(p_SNTP_PRETEND_TIME, "%lld", &ll))
1237 				pretend_time = (time_t)ll;
1238 #else
1239 # include "GRONK: unexpected value for SIZEOF_TIME_T"
1240 #endif
1241 			if (0 != pretend_time)
1242 				tv_dst.tv_sec = pretend_time;
1243 		}
1244 
1245 		offset_calculation(rpkt, rpktl, &tv_dst, &offset,
1246 				   &precision, &synch_distance);
1247 		time_derived = TRUE;
1248 
1249 		for (digits = 0; (precision *= 10.) < 1.; ++digits)
1250 			/* empty */ ;
1251 		if (digits > 6)
1252 			digits = 6;
1253 
1254 		ts_str = tv_to_str(&tv_dst);
1255 		stratum = rpkt->stratum;
1256 		if (0 == stratum)
1257 				stratum = 16;
1258 
1259 		if (synch_distance > 0.) {
1260 			cnt = snprintf(disptxt, sizeof(disptxt),
1261 				       " +/- %f", synch_distance);
1262 			if ((size_t)cnt >= sizeof(disptxt))
1263 				snprintf(disptxt, sizeof(disptxt),
1264 					 "ERROR %d >= %d", cnt,
1265 					 (int)sizeof(disptxt));
1266 		} else {
1267 			disptxt[0] = '\0';
1268 		}
1269 
1270 		switch (PKT_LEAP(rpkt->li_vn_mode)) {
1271 		    case LEAP_NOWARNING:
1272 		    	leaptxt = "no-leap";
1273 			break;
1274 		    case LEAP_ADDSECOND:
1275 		    	leaptxt = "add-leap";
1276 			break;
1277 		    case LEAP_DELSECOND:
1278 		    	leaptxt = "del-leap";
1279 			break;
1280 		    case LEAP_NOTINSYNC:
1281 		    	leaptxt = "unsync";
1282 			break;
1283 		    default:
1284 		    	leaptxt = "LEAP-ERROR";
1285 			break;
1286 		}
1287 
1288 		msyslog(LOG_INFO, "%s %+.*f%s %s s%d %s%s", ts_str,
1289 			digits, offset, disptxt,
1290 			hostnameaddr(hostname, host), stratum,
1291 			leaptxt,
1292 			(time_adjusted)
1293 			    ? " [excess]"
1294 			    : "");
1295 		free(ts_str);
1296 
1297 		if (p_SNTP_PRETEND_TIME)
1298 			return 0;
1299 
1300 		if (!time_adjusted &&
1301 		    (ENABLED_OPT(STEP) || ENABLED_OPT(SLEW)))
1302 			return set_time(offset);
1303 
1304 		return EX_OK;
1305 	}
1306 
1307 	return 1;
1308 }
1309 
1310 
1311 void
1312 offset_calculation(
1313 	struct pkt *rpkt,
1314 	int rpktl,
1315 	struct timeval *tv_dst,
1316 	double *offset,
1317 	double *precision,
1318 	double *synch_distance
1319 	)
1320 {
1321 	l_fp p_rec, p_xmt, p_ref, p_org, tmp, dst;
1322 	u_fp p_rdly, p_rdsp;
1323 	double t21, t34, delta;
1324 
1325 	/* Convert timestamps from network to host byte order */
1326 	p_rdly = NTOHS_FP(rpkt->rootdelay);
1327 	p_rdsp = NTOHS_FP(rpkt->rootdisp);
1328 	NTOHL_FP(&rpkt->reftime, &p_ref);
1329 	NTOHL_FP(&rpkt->org, &p_org);
1330 	NTOHL_FP(&rpkt->rec, &p_rec);
1331 	NTOHL_FP(&rpkt->xmt, &p_xmt);
1332 
1333 	*precision = LOGTOD(rpkt->precision);
1334 
1335 	TRACE(3, ("offset_calculation: LOGTOD(rpkt->precision): %f\n", *precision));
1336 
1337 	/* Compute offset etc. */
1338 	tmp = p_rec;
1339 	L_SUB(&tmp, &p_org);
1340 	LFPTOD(&tmp, t21);
1341 	TVTOTS(tv_dst, &dst);
1342 	dst.l_ui += JAN_1970;
1343 	tmp = p_xmt;
1344 	L_SUB(&tmp, &dst);
1345 	LFPTOD(&tmp, t34);
1346 	*offset = (t21 + t34) / 2.;
1347 	delta = t21 - t34;
1348 
1349 	// synch_distance is:
1350 	// (peer->delay + peer->rootdelay) / 2 + peer->disp
1351 	// + peer->rootdisp + clock_phi * (current_time - peer->update)
1352 	// + peer->jitter;
1353 	//
1354 	// and peer->delay = fabs(peer->offset - p_offset) * 2;
1355 	// and peer->offset needs history, so we're left with
1356 	// p_offset = (t21 + t34) / 2.;
1357 	// peer->disp = 0; (we have no history to augment this)
1358 	// clock_phi = 15e-6;
1359 	// peer->jitter = LOGTOD(sys_precision); (we have no history to augment this)
1360 	// and ntp_proto.c:set_sys_tick_precision() should get us sys_precision.
1361 	//
1362 	// so our answer seems to be:
1363 	//
1364 	// (fabs(t21 + t34) + peer->rootdelay) / 3.
1365 	// + 0 (peer->disp)
1366 	// + peer->rootdisp
1367 	// + 15e-6 (clock_phi)
1368 	// + LOGTOD(sys_precision)
1369 
1370 	INSIST( FPTOD(p_rdly) >= 0. );
1371 #if 1
1372 	*synch_distance = (fabs(t21 + t34) + FPTOD(p_rdly)) / 3.
1373 		+ 0.
1374 		+ FPTOD(p_rdsp)
1375 		+ 15e-6
1376 		+ 0.	/* LOGTOD(sys_precision) when we can get it */
1377 		;
1378 	INSIST( *synch_distance >= 0. );
1379 #else
1380 	*synch_distance = (FPTOD(p_rdly) + FPTOD(p_rdsp))/2.0;
1381 #endif
1382 
1383 #ifdef DEBUG
1384 	if (debug > 3) {
1385 		printf("sntp rootdelay: %f\n", FPTOD(p_rdly));
1386 		printf("sntp rootdisp: %f\n", FPTOD(p_rdsp));
1387 		printf("sntp syncdist: %f\n", *synch_distance);
1388 
1389 		pkt_output(rpkt, rpktl, stdout);
1390 
1391 		printf("sntp offset_calculation: rpkt->reftime:\n");
1392 		l_fp_output(&p_ref, stdout);
1393 		printf("sntp offset_calculation: rpkt->org:\n");
1394 		l_fp_output(&p_org, stdout);
1395 		printf("sntp offset_calculation: rpkt->rec:\n");
1396 		l_fp_output(&p_rec, stdout);
1397 		printf("sntp offset_calculation: rpkt->xmt:\n");
1398 		l_fp_output(&p_xmt, stdout);
1399 	}
1400 #endif
1401 
1402 	TRACE(3, ("sntp offset_calculation:\trec - org t21: %.6f\n"
1403 		  "\txmt - dst t34: %.6f\tdelta: %.6f\toffset: %.6f\n",
1404 		  t21, t34, delta, *offset));
1405 
1406 	return;
1407 }
1408 
1409 
1410 
1411 /* Compute the 8 bits for li_vn_mode */
1412 void
1413 set_li_vn_mode (
1414 	struct pkt *spkt,
1415 	char leap,
1416 	char version,
1417 	char mode
1418 	)
1419 {
1420 	if (leap > 3) {
1421 		msyslog(LOG_DEBUG, "set_li_vn_mode: leap > 3, using max. 3");
1422 		leap = 3;
1423 	}
1424 
1425 	if ((unsigned char)version > 7) {
1426 		msyslog(LOG_DEBUG, "set_li_vn_mode: version < 0 or > 7, using 4");
1427 		version = 4;
1428 	}
1429 
1430 	if (mode > 7) {
1431 		msyslog(LOG_DEBUG, "set_li_vn_mode: mode > 7, using client mode 3");
1432 		mode = 3;
1433 	}
1434 
1435 	spkt->li_vn_mode  = leap << 6;
1436 	spkt->li_vn_mode |= version << 3;
1437 	spkt->li_vn_mode |= mode;
1438 }
1439 
1440 
1441 /*
1442 ** set_time applies 'offset' to the local clock.
1443 */
1444 int
1445 set_time(
1446 	double offset
1447 	)
1448 {
1449 	int rc;
1450 
1451 	if (time_adjusted)
1452 		return EX_OK;
1453 
1454 	/*
1455 	** If we can step but we cannot slew, then step.
1456 	** If we can step or slew and and |offset| > steplimit, then step.
1457 	*/
1458 	if (ENABLED_OPT(STEP) &&
1459 	    (   !ENABLED_OPT(SLEW)
1460 	     || (ENABLED_OPT(SLEW) && (fabs(offset) > steplimit))
1461 	    )) {
1462 		rc = step_systime(offset);
1463 
1464 		/* If there was a problem, can we rely on errno? */
1465 		if (1 == rc)
1466 			time_adjusted = TRUE;
1467 		return (time_adjusted)
1468 			   ? EX_OK
1469 			   : 1;
1470 		/*
1471 		** In case of error, what should we use?
1472 		** EX_UNAVAILABLE?
1473 		** EX_OSERR?
1474 		** EX_NOPERM?
1475 		*/
1476 	}
1477 
1478 	if (ENABLED_OPT(SLEW)) {
1479 		rc = adj_systime(offset);
1480 
1481 		/* If there was a problem, can we rely on errno? */
1482 		if (1 == rc)
1483 			time_adjusted = TRUE;
1484 		return (time_adjusted)
1485 			   ? EX_OK
1486 			   : 1;
1487 		/*
1488 		** In case of error, what should we use?
1489 		** EX_UNAVAILABLE?
1490 		** EX_OSERR?
1491 		** EX_NOPERM?
1492 		*/
1493 	}
1494 
1495 	return EX_SOFTWARE;
1496 }
1497 
1498 
1499 int
1500 libevent_version_ok(void)
1501 {
1502 	ev_uint32_t v_compile_maj;
1503 	ev_uint32_t v_run_maj;
1504 
1505 	v_compile_maj = LIBEVENT_VERSION_NUMBER & 0xffff0000;
1506 	v_run_maj = event_get_version_number() & 0xffff0000;
1507 	if (v_compile_maj != v_run_maj) {
1508 		fprintf(stderr,
1509 			"Incompatible libevent versions: have %s, built with %s\n",
1510 			event_get_version(),
1511 			LIBEVENT_VERSION);
1512 		return 0;
1513 	}
1514 	return 1;
1515 }
1516 
1517 /*
1518  * gettimeofday_cached()
1519  *
1520  * Clones the event_base_gettimeofday_cached() interface but ensures the
1521  * times are always on the gettimeofday() 1970 scale.  Older libevent 2
1522  * sometimes used gettimeofday(), sometimes the since-system-start
1523  * clock_gettime(CLOCK_MONOTONIC), depending on the platform.
1524  *
1525  * It is not cleanly possible to tell which timescale older libevent is
1526  * using.
1527  *
1528  * The strategy involves 1 hour thresholds chosen to be far longer than
1529  * the duration of a round of libevent callbacks, which share a cached
1530  * start-of-round time.  First compare the last cached time with the
1531  * current gettimeofday() time.  If they are within one hour, libevent
1532  * is using the proper timescale so leave the offset 0.  Otherwise,
1533  * compare libevent's cached time and the current time on the monotonic
1534  * scale.  If they are within an hour, libevent is using the monotonic
1535  * scale so calculate the offset to add to such times to bring them to
1536  * gettimeofday()'s scale.
1537  */
1538 int
1539 gettimeofday_cached(
1540 	struct event_base *	b,
1541 	struct timeval *	caller_tv
1542 	)
1543 {
1544 #if defined(_EVENT_HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC)
1545 	static struct event_base *	cached_b;
1546 	static struct timeval		cached;
1547 	static struct timeval		adj_cached;
1548 	static struct timeval		offset;
1549 	static int			offset_ready;
1550 	struct timeval			latest;
1551 	struct timeval			systemt;
1552 	struct timespec			ts;
1553 	struct timeval			mono;
1554 	struct timeval			diff;
1555 	int				cgt_rc;
1556 	int				gtod_rc;
1557 
1558 	event_base_gettimeofday_cached(b, &latest);
1559 	if (b == cached_b &&
1560 	    !memcmp(&latest, &cached, sizeof(latest))) {
1561 		*caller_tv = adj_cached;
1562 		return 0;
1563 	}
1564 	cached = latest;
1565 	cached_b = b;
1566 	if (!offset_ready) {
1567 		cgt_rc = clock_gettime(CLOCK_MONOTONIC, &ts);
1568 		gtod_rc = gettimeofday(&systemt, NULL);
1569 		if (0 != gtod_rc) {
1570 			msyslog(LOG_ERR,
1571 				"%s: gettimeofday() error %m",
1572 				progname);
1573 			exit(1);
1574 		}
1575 		diff = sub_tval(systemt, latest);
1576 		if (debug > 1)
1577 			printf("system minus cached %+ld.%06ld\n",
1578 			       (long)diff.tv_sec, (long)diff.tv_usec);
1579 		if (0 != cgt_rc || labs((long)diff.tv_sec) < 3600) {
1580 			/*
1581 			 * Either use_monotonic == 0, or this libevent
1582 			 * has been repaired.  Leave offset at zero.
1583 			 */
1584 		} else {
1585 			mono.tv_sec = ts.tv_sec;
1586 			mono.tv_usec = ts.tv_nsec / 1000;
1587 			diff = sub_tval(latest, mono);
1588 			if (debug > 1)
1589 				printf("cached minus monotonic %+ld.%06ld\n",
1590 				       (long)diff.tv_sec, (long)diff.tv_usec);
1591 			if (labs((long)diff.tv_sec) < 3600) {
1592 				/* older libevent2 using monotonic */
1593 				offset = sub_tval(systemt, mono);
1594 				TRACE(1, ("%s: Offsetting libevent CLOCK_MONOTONIC times  by %+ld.%06ld\n",
1595 					 "gettimeofday_cached",
1596 					 (long)offset.tv_sec,
1597 					 (long)offset.tv_usec));
1598 			}
1599 		}
1600 		offset_ready = TRUE;
1601 	}
1602 	adj_cached = add_tval(cached, offset);
1603 	*caller_tv = adj_cached;
1604 
1605 	return 0;
1606 #else
1607 	return event_base_gettimeofday_cached(b, caller_tv);
1608 #endif
1609 }
1610 
1611 /* Dummy function to satisfy libntp/work_fork.c */
1612 int
1613 set_user_group_ids(
1614 	)
1615 {
1616     return 1;
1617 }
1618