xref: /freebsd/contrib/ntp/ntpd/ntp_io.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*
2  * ntp_io.c - input/output routines for ntpd.	The socket-opening code
3  *		   was shamelessly stolen from ntpd.
4  */
5 
6 #ifdef HAVE_CONFIG_H
7 # include <config.h>
8 #endif
9 
10 #include <stdio.h>
11 #include <signal.h>
12 #ifdef HAVE_FNMATCH_H
13 # include <fnmatch.h>
14 # if !defined(FNM_CASEFOLD) && defined(FNM_IGNORECASE)
15 #  define FNM_CASEFOLD FNM_IGNORECASE
16 # endif
17 #endif
18 #ifdef HAVE_SYS_PARAM_H
19 # include <sys/param.h>
20 #endif
21 #ifdef HAVE_SYS_IOCTL_H
22 # include <sys/ioctl.h>
23 #endif
24 #ifdef HAVE_SYS_SOCKIO_H	/* UXPV: SIOC* #defines (Frank Vance <fvance@waii.com>) */
25 # include <sys/sockio.h>
26 #endif
27 #ifdef HAVE_SYS_UIO_H
28 # include <sys/uio.h>
29 #endif
30 
31 #include "ntp_machine.h"
32 #include "ntpd.h"
33 #include "ntp_io.h"
34 #include "iosignal.h"
35 #include "ntp_lists.h"
36 #include "ntp_refclock.h"
37 #include "ntp_stdlib.h"
38 #include "ntp_worker.h"
39 #include "ntp_request.h"
40 #include "ntp_assert.h"
41 #include "timevalops.h"
42 #include "timespecops.h"
43 #include "ntpd-opts.h"
44 
45 /* Don't include ISC's version of IPv6 variables and structures */
46 #define ISC_IPV6_H 1
47 #include <isc/mem.h>
48 #include <isc/interfaceiter.h>
49 #include <isc/netaddr.h>
50 #include <isc/result.h>
51 #include <isc/sockaddr.h>
52 
53 #ifdef SIM
54 #include "ntpsim.h"
55 #endif
56 
57 #ifdef HAS_ROUTING_SOCKET
58 # include <net/route.h>
59 # ifdef HAVE_RTNETLINK
60 #  include <linux/rtnetlink.h>
61 # endif
62 #endif
63 
64 
65 /*
66  * setsockopt does not always have the same arg declaration
67  * across all platforms. If it's not defined we make it empty
68  */
69 
70 #ifndef SETSOCKOPT_ARG_CAST
71 #define SETSOCKOPT_ARG_CAST
72 #endif
73 
74 extern int listen_to_virtual_ips;
75 
76 #ifndef IPTOS_DSCP_EF
77 #define IPTOS_DSCP_EF 0xb8
78 #endif
79 int qos = IPTOS_DSCP_EF;	/* QoS RFC3246 */
80 
81 #ifdef LEAP_SMEAR
82 /* TODO burnicki: This should be moved to ntp_timer.c, but if we do so
83  * we get a linker error. Since we're running out of time before the leap
84  * second occurs, we let it here where it just works.
85  */
86 int leap_smear_intv;
87 #endif
88 
89 /*
90  * NIC rule entry
91  */
92 typedef struct nic_rule_tag nic_rule;
93 
94 struct nic_rule_tag {
95 	nic_rule *	next;
96 	nic_rule_action	action;
97 	nic_rule_match	match_type;
98 	char *		if_name;
99 	sockaddr_u	addr;
100 	int		prefixlen;
101 };
102 
103 /*
104  * NIC rule listhead.  Entries are added at the head so that the first
105  * match in the list is the last matching rule specified.
106  */
107 nic_rule *nic_rule_list;
108 
109 
110 #if defined(SO_BINTIME) && defined(SCM_BINTIME) && defined(CMSG_FIRSTHDR)
111 #  define HAVE_PACKET_TIMESTAMP
112 #  define HAVE_BINTIME
113 #  ifdef BINTIME_CTLMSGBUF_SIZE
114 #   define CMSG_BUFSIZE BINTIME_CTLMSGBUF_SIZE
115 #  else
116 #   define CMSG_BUFSIZE  1536 /* moderate default */
117 #  endif
118 #elif defined(SO_TIMESTAMPNS) && defined(SCM_TIMESTAMPNS) && defined(CMSG_FIRSTHDR)
119 #  define HAVE_PACKET_TIMESTAMP
120 #  define HAVE_TIMESTAMPNS
121 #  ifdef TIMESTAMPNS_CTLMSGBUF_SIZE
122 #   define CMSG_BUFSIZE TIMESTAMPNS_CTLMSGBUF_SIZE
123 #  else
124 #   define CMSG_BUFSIZE  1536 /* moderate default */
125 #  endif
126 #elif defined(SO_TIMESTAMP) && defined(SCM_TIMESTAMP) && defined(CMSG_FIRSTHDR)
127 #  define HAVE_PACKET_TIMESTAMP
128 #  define HAVE_TIMESTAMP
129 #  ifdef TIMESTAMP_CTLMSGBUF_SIZE
130 #   define CMSG_BUFSIZE TIMESTAMP_CTLMSGBUF_SIZE
131 #  else
132 #   define CMSG_BUFSIZE  1536 /* moderate default */
133 #  endif
134 #else
135 /* fill in for old/other timestamp interfaces */
136 #endif
137 
138 #if defined(SYS_WINNT)
139 #include "win32_io.h"
140 #include <isc/win32os.h>
141 #endif
142 
143 /*
144  * We do asynchronous input using the SIGIO facility.  A number of
145  * recvbuf buffers are preallocated for input.	In the signal
146  * handler we poll to see which sockets are ready and read the
147  * packets from them into the recvbuf's along with a time stamp and
148  * an indication of the source host and the interface it was received
149  * through.  This allows us to get as accurate receive time stamps
150  * as possible independent of other processing going on.
151  *
152  * We watch the number of recvbufs available to the signal handler
153  * and allocate more when this number drops below the low water
154  * mark.  If the signal handler should run out of buffers in the
155  * interim it will drop incoming frames, the idea being that it is
156  * better to drop a packet than to be inaccurate.
157  */
158 
159 
160 /*
161  * Other statistics of possible interest
162  */
163 volatile u_long packets_dropped;	/* total number of packets dropped on reception */
164 volatile u_long packets_ignored;	/* packets received on wild card interface */
165 volatile u_long packets_received;	/* total number of packets received */
166 	 u_long packets_sent;		/* total number of packets sent */
167 	 u_long packets_notsent;	/* total number of packets which couldn't be sent */
168 
169 volatile u_long handler_calls;	/* number of calls to interrupt handler */
170 volatile u_long handler_pkts;	/* number of pkts received by handler */
171 u_long io_timereset;		/* time counters were reset */
172 
173 /*
174  * Interface stuff
175  */
176 endpt *	any_interface;		/* wildcard ipv4 interface */
177 endpt *	any6_interface;		/* wildcard ipv6 interface */
178 endpt *	loopback_interface;	/* loopback ipv4 interface */
179 
180 isc_boolean_t broadcast_client_enabled;	/* is broadcast client enabled */
181 u_int sys_ifnum;			/* next .ifnum to assign */
182 int ninterfaces;			/* Total number of interfaces */
183 
184 int disable_dynamic_updates;		/* scan interfaces once only */
185 
186 #ifdef REFCLOCK
187 /*
188  * Refclock stuff.	We keep a chain of structures with data concerning
189  * the guys we are doing I/O for.
190  */
191 static	struct refclockio *refio;
192 #endif /* REFCLOCK */
193 
194 /*
195  * File descriptor masks etc. for call to select
196  * Not needed for I/O Completion Ports or anything outside this file
197  */
198 static fd_set activefds;
199 static int maxactivefd;
200 
201 /*
202  * bit alternating value to detect verified interfaces during an update cycle
203  */
204 static  u_short		sys_interphase = 0;
205 
206 static endpt *	new_interface(endpt *);
207 static void	add_interface(endpt *);
208 static int	update_interfaces(u_short, interface_receiver_t,
209 				  void *);
210 static void	remove_interface(endpt *);
211 static endpt *	create_interface(u_short, endpt *);
212 
213 static int	is_wildcard_addr	(const sockaddr_u *);
214 
215 /*
216  * Multicast functions
217  */
218 static	isc_boolean_t	addr_ismulticast	(sockaddr_u *);
219 static	isc_boolean_t	is_not_bindable		(sockaddr_u *,
220 						 const char *);
221 
222 /*
223  * Not all platforms support multicast
224  */
225 #ifdef MCAST
226 static	isc_boolean_t	socket_multicast_enable	(endpt *, sockaddr_u *);
227 static	isc_boolean_t	socket_multicast_disable(endpt *, sockaddr_u *);
228 #endif
229 
230 #ifdef DEBUG
231 static void interface_dump	(const endpt *);
232 static void sockaddr_dump	(const sockaddr_u *);
233 static void print_interface	(const endpt *, const char *, const char *);
234 #define DPRINT_INTERFACE(level, args) do { if (debug >= (level)) { print_interface args; } } while (0)
235 #else
236 #define DPRINT_INTERFACE(level, args) do {} while (0)
237 #endif
238 
239 typedef struct vsock vsock_t;
240 enum desc_type { FD_TYPE_SOCKET, FD_TYPE_FILE };
241 
242 struct vsock {
243 	vsock_t	*	link;
244 	SOCKET		fd;
245 	enum desc_type	type;
246 };
247 
248 vsock_t	*fd_list;
249 
250 #if !defined(HAVE_IO_COMPLETION_PORT) && defined(HAS_ROUTING_SOCKET)
251 /*
252  * async notification processing (e. g. routing sockets)
253  */
254 /*
255  * support for receiving data on fd that is not a refclock or a socket
256  * like e. g. routing sockets
257  */
258 struct asyncio_reader {
259 	struct asyncio_reader *link;		    /* the list this is being kept in */
260 	SOCKET fd;				    /* fd to be read */
261 	void  *data;				    /* possibly local data */
262 	void (*receiver)(struct asyncio_reader *);  /* input handler */
263 };
264 
265 struct asyncio_reader *asyncio_reader_list;
266 
267 static void delete_asyncio_reader (struct asyncio_reader *);
268 static struct asyncio_reader *new_asyncio_reader (void);
269 static void add_asyncio_reader (struct asyncio_reader *, enum desc_type);
270 static void remove_asyncio_reader (struct asyncio_reader *);
271 
272 #endif /* !defined(HAVE_IO_COMPLETION_PORT) && defined(HAS_ROUTING_SOCKET) */
273 
274 static void init_async_notifications (void);
275 
276 static	int	addr_eqprefix	(const sockaddr_u *, const sockaddr_u *,
277 				 int);
278 static int	addr_samesubnet	(const sockaddr_u *, const sockaddr_u *,
279 				 const sockaddr_u *, const sockaddr_u *);
280 static	int	create_sockets	(u_short);
281 static	SOCKET	open_socket	(sockaddr_u *, int, int, endpt *);
282 static	char *	fdbits		(int, fd_set *);
283 static	void	set_reuseaddr	(int);
284 static	isc_boolean_t	socket_broadcast_enable	 (struct interface *, SOCKET, sockaddr_u *);
285 #ifdef  OS_MISSES_SPECIFIC_ROUTE_UPDATES
286 static	isc_boolean_t	socket_broadcast_disable (struct interface *, sockaddr_u *);
287 #endif
288 
289 typedef struct remaddr remaddr_t;
290 
291 struct remaddr {
292 	remaddr_t *		link;
293 	sockaddr_u		addr;
294 	endpt *			ep;
295 };
296 
297 remaddr_t *	remoteaddr_list;
298 endpt *		ep_list;	/* complete endpt list */
299 endpt *		mc4_list;	/* IPv4 mcast-capable unicast endpts */
300 endpt *		mc6_list;	/* IPv6 mcast-capable unicast endpts */
301 
302 static endpt *	wildipv4;
303 static endpt *	wildipv6;
304 
305 #ifdef SYS_WINNT
306 int accept_wildcard_if_for_winnt;
307 #else
308 const int accept_wildcard_if_for_winnt = FALSE;
309 #endif
310 
311 static void	add_fd_to_list		(SOCKET, enum desc_type);
312 static endpt *	find_addr_in_list	(sockaddr_u *);
313 static endpt *	find_flagged_addr_in_list(sockaddr_u *, u_int32);
314 static void	delete_addr_from_list	(sockaddr_u *);
315 static void	delete_interface_from_list(endpt *);
316 static void	close_and_delete_fd_from_list(SOCKET);
317 static void	add_addr_to_list	(sockaddr_u *, endpt *);
318 static void	create_wildcards	(u_short);
319 static endpt *	findlocalinterface	(sockaddr_u *, int, int);
320 static endpt *	findclosestinterface	(sockaddr_u *, int);
321 #ifdef DEBUG
322 static const char *	action_text	(nic_rule_action);
323 #endif
324 static nic_rule_action	interface_action(char *, sockaddr_u *, u_int32);
325 static void		convert_isc_if	(isc_interface_t *,
326 					 endpt *, u_short);
327 static void		calc_addr_distance(sockaddr_u *,
328 					   const sockaddr_u *,
329 					   const sockaddr_u *);
330 static int		cmp_addr_distance(const sockaddr_u *,
331 					  const sockaddr_u *);
332 
333 /*
334  * Routines to read the ntp packets
335  */
336 #if !defined(HAVE_IO_COMPLETION_PORT)
337 static inline int	read_network_packet	(SOCKET, struct interface *, l_fp);
338 static void		ntpd_addremove_io_fd	(int, int, int);
339 static input_handler_t  input_handler;
340 #ifdef REFCLOCK
341 static inline int	read_refclock_packet	(SOCKET, struct refclockio *, l_fp);
342 #endif
343 #endif
344 
345 
346 
347 #ifndef HAVE_IO_COMPLETION_PORT
348 void
349 maintain_activefds(
350 	int fd,
351 	int closing
352 	)
353 {
354 	int i;
355 
356 	if (fd < 0 || fd >= FD_SETSIZE) {
357 		msyslog(LOG_ERR,
358 			"Too many sockets in use, FD_SETSIZE %d exceeded by fd %d",
359 			FD_SETSIZE, fd);
360 		exit(1);
361 	}
362 
363 	if (!closing) {
364 		FD_SET(fd, &activefds);
365 		maxactivefd = max(fd, maxactivefd);
366 	} else {
367 		FD_CLR(fd, &activefds);
368 		if (maxactivefd && fd == maxactivefd) {
369 			for (i = maxactivefd - 1; i >= 0; i--)
370 				if (FD_ISSET(i, &activefds)) {
371 					maxactivefd = i;
372 					break;
373 				}
374 			NTP_INSIST(fd != maxactivefd);
375 		}
376 	}
377 }
378 #endif	/* !HAVE_IO_COMPLETION_PORT */
379 
380 
381 #ifdef DEBUG_TIMING
382 /*
383  * collect timing information for various processing
384  * paths. currently we only pass them on to the file
385  * for later processing. this could also do histogram
386  * based analysis in other to reduce the load (and skew)
387  * dur to the file output
388  */
389 void
390 collect_timing(struct recvbuf *rb, const char *tag, int count, l_fp *dts)
391 {
392 	char buf[256];
393 
394 	snprintf(buf, sizeof(buf), "%s %d %s %s",
395 		 (rb != NULL)
396 		     ? ((rb->dstadr != NULL)
397 			    ? stoa(&rb->recv_srcadr)
398 			    : "-REFCLOCK-")
399 		     : "-",
400 		 count, lfptoa(dts, 9), tag);
401 	record_timing_stats(buf);
402 }
403 #endif
404 
405 /*
406  * About dynamic interfaces, sockets, reception and more...
407  *
408  * the code solves following tasks:
409  *
410  *   - keep a current list of active interfaces in order
411  *     to bind to to the interface address on NTP_PORT so that
412  *     all wild and specific bindings for NTP_PORT are taken by ntpd
413  *     to avoid other daemons messing with the time or sockets.
414  *   - all interfaces keep a list of peers that are referencing
415  *     the interface in order to quickly re-assign the peers to
416  *     new interface in case an interface is deleted (=> gone from system or
417  *     down)
418  *   - have a preconfigured socket ready with the right local address
419  *     for transmission and reception
420  *   - have an address list for all destination addresses used within ntpd
421  *     to find the "right" preconfigured socket.
422  *   - facilitate updating the internal interface list with respect to
423  *     the current kernel state
424  *
425  * special issues:
426  *
427  *   - mapping of multicast addresses to the interface affected is not always
428  *     one to one - especially on hosts with multiple interfaces
429  *     the code here currently allocates a separate interface entry for those
430  *     multicast addresses
431  *     iff it is able to bind to a *new* socket with the multicast address (flags |= MCASTIF)
432  *     in case of failure the multicast address is bound to an existing interface.
433  *   - on some systems it is perfectly legal to assign the same address to
434  *     multiple interfaces. Therefore this code does not keep a list of interfaces
435  *     but a list of interfaces that represent a unique address as determined by the kernel
436  *     by the procedure in findlocalinterface. Thus it is perfectly legal to see only
437  *     one representative of a group of real interfaces if they share the same address.
438  *
439  * Frank Kardel 20050910
440  */
441 
442 /*
443  * init_io - initialize I/O module.
444  */
445 void
446 init_io(void)
447 {
448 	/* Init buffer free list and stat counters */
449 	init_recvbuff(RECV_INIT);
450 	/* update interface every 5 minutes as default */
451 	interface_interval = 300;
452 
453 #ifdef WORK_PIPE
454 	addremove_io_fd = &ntpd_addremove_io_fd;
455 #endif
456 
457 #ifdef SYS_WINNT
458 	init_io_completion_port();
459 #endif
460 
461 #if defined(HAVE_SIGNALED_IO)
462 	(void) set_signal(input_handler);
463 #endif
464 }
465 
466 
467 static void
468 ntpd_addremove_io_fd(
469 	int	fd,
470 	int	is_pipe,
471 	int	remove_it
472 	)
473 {
474 	UNUSED_ARG(is_pipe);
475 
476 #ifdef HAVE_SIGNALED_IO
477 	init_socket_sig(fd);
478 #endif /* not HAVE_SIGNALED_IO */
479 
480 	maintain_activefds(fd, remove_it);
481 }
482 
483 
484 /*
485  * io_open_sockets - call socket creation routine
486  */
487 void
488 io_open_sockets(void)
489 {
490 	static int already_opened;
491 
492 	if (already_opened || HAVE_OPT( SAVECONFIGQUIT ))
493 		return;
494 
495 	already_opened = 1;
496 
497 	/*
498 	 * Create the sockets
499 	 */
500 	BLOCKIO();
501 	create_sockets(NTP_PORT);
502 	UNBLOCKIO();
503 
504 	init_async_notifications();
505 
506 	DPRINTF(3, ("io_open_sockets: maxactivefd %d\n", maxactivefd));
507 }
508 
509 
510 #ifdef DEBUG
511 /*
512  * function to dump the contents of the interface structure
513  * for debugging use only.
514  */
515 void
516 interface_dump(const endpt *itf)
517 {
518 	printf("Dumping interface: %p\n", itf);
519 	printf("fd = %d\n", itf->fd);
520 	printf("bfd = %d\n", itf->bfd);
521 	printf("sin = %s,\n", stoa(&itf->sin));
522 	sockaddr_dump(&itf->sin);
523 	printf("bcast = %s,\n", stoa(&itf->bcast));
524 	sockaddr_dump(&itf->bcast);
525 	printf("mask = %s,\n", stoa(&itf->mask));
526 	sockaddr_dump(&itf->mask);
527 	printf("name = %s\n", itf->name);
528 	printf("flags = 0x%08x\n", itf->flags);
529 	printf("last_ttl = %d\n", itf->last_ttl);
530 	printf("addr_refid = %08x\n", itf->addr_refid);
531 	printf("num_mcast = %d\n", itf->num_mcast);
532 	printf("received = %ld\n", itf->received);
533 	printf("sent = %ld\n", itf->sent);
534 	printf("notsent = %ld\n", itf->notsent);
535 	printf("ifindex = %u\n", itf->ifindex);
536 	printf("peercnt = %u\n", itf->peercnt);
537 	printf("phase = %u\n", itf->phase);
538 }
539 
540 /*
541  * sockaddr_dump - hex dump the start of a sockaddr_u
542  */
543 static void
544 sockaddr_dump(const sockaddr_u *psau)
545 {
546 	/* Limit the size of the sockaddr_in6 hex dump */
547 	const int maxsize = min(32, sizeof(psau->sa6));
548 	const u_char *	cp;
549 	int		i;
550 
551 	/* XXX: Should we limit maxsize based on psau->saX.sin_family? */
552 	cp = (const void *)&psau->sa6;
553 
554 	for(i = 0; i < maxsize; i++) {
555 		printf("%02x", *cp++);
556 		if (!((i + 1) % 4))
557 			printf(" ");
558 	}
559 	printf("\n");
560 }
561 
562 /*
563  * print_interface - helper to output debug information
564  */
565 static void
566 print_interface(const endpt *iface, const char *pfx, const char *sfx)
567 {
568 	printf("%sinterface #%d: fd=%d, bfd=%d, name=%s, flags=0x%x, ifindex=%u, sin=%s",
569 	       pfx,
570 	       iface->ifnum,
571 	       iface->fd,
572 	       iface->bfd,
573 	       iface->name,
574 	       iface->flags,
575 	       iface->ifindex,
576 	       stoa(&iface->sin));
577 	if (AF_INET == iface->family) {
578 		if (iface->flags & INT_BROADCAST)
579 			printf(", bcast=%s", stoa(&iface->bcast));
580 		printf(", mask=%s", stoa(&iface->mask));
581 	}
582 	printf(", %s:%s",
583 	       (iface->ignore_packets)
584 		   ? "Disabled"
585 		   : "Enabled",
586 	       sfx);
587 	if (debug > 4)	/* in-depth debugging only */
588 		interface_dump(iface);
589 }
590 #endif
591 
592 #if !defined(HAVE_IO_COMPLETION_PORT) && defined(HAS_ROUTING_SOCKET)
593 /*
594  * create an asyncio_reader structure
595  */
596 static struct asyncio_reader *
597 new_asyncio_reader(void)
598 {
599 	struct asyncio_reader *reader;
600 
601 	reader = emalloc_zero(sizeof(*reader));
602 	reader->fd = INVALID_SOCKET;
603 
604 	return reader;
605 }
606 
607 /*
608  * delete a reader
609  */
610 static void
611 delete_asyncio_reader(
612 	struct asyncio_reader *reader
613 	)
614 {
615 	free(reader);
616 }
617 
618 /*
619  * add asynchio_reader
620  */
621 static void
622 add_asyncio_reader(
623 	struct asyncio_reader *	reader,
624 	enum desc_type		type)
625 {
626 	LINK_SLIST(asyncio_reader_list, reader, link);
627 	add_fd_to_list(reader->fd, type);
628 }
629 
630 /*
631  * remove asynchio_reader
632  */
633 static void
634 remove_asyncio_reader(
635 	struct asyncio_reader *reader
636 	)
637 {
638 	struct asyncio_reader *unlinked;
639 
640 	UNLINK_SLIST(unlinked, asyncio_reader_list, reader, link,
641 	    struct asyncio_reader);
642 
643 	if (reader->fd != INVALID_SOCKET)
644 		close_and_delete_fd_from_list(reader->fd);
645 
646 	reader->fd = INVALID_SOCKET;
647 }
648 #endif /* !defined(HAVE_IO_COMPLETION_PORT) && defined(HAS_ROUTING_SOCKET) */
649 
650 
651 /* compare two sockaddr prefixes */
652 static int
653 addr_eqprefix(
654 	const sockaddr_u *	a,
655 	const sockaddr_u *	b,
656 	int			prefixlen
657 	)
658 {
659 	isc_netaddr_t		isc_a;
660 	isc_netaddr_t		isc_b;
661 	isc_sockaddr_t		isc_sa;
662 
663 	ZERO(isc_sa);
664 	memcpy(&isc_sa.type, a, min(sizeof(isc_sa.type), sizeof(*a)));
665 	isc_netaddr_fromsockaddr(&isc_a, &isc_sa);
666 
667 	ZERO(isc_sa);
668 	memcpy(&isc_sa.type, b, min(sizeof(isc_sa.type), sizeof(*b)));
669 	isc_netaddr_fromsockaddr(&isc_b, &isc_sa);
670 
671 	return (int)isc_netaddr_eqprefix(&isc_a, &isc_b,
672 					 (u_int)prefixlen);
673 }
674 
675 
676 static int
677 addr_samesubnet(
678 	const sockaddr_u *	a,
679 	const sockaddr_u *	a_mask,
680 	const sockaddr_u *	b,
681 	const sockaddr_u *	b_mask
682 	)
683 {
684 	const u_int32 *	pa;
685 	const u_int32 *	pa_limit;
686 	const u_int32 *	pb;
687 	const u_int32 *	pm;
688 	size_t		loops;
689 
690 	NTP_REQUIRE(AF(a) == AF(a_mask));
691 	NTP_REQUIRE(AF(b) == AF(b_mask));
692 	/*
693 	 * With address and mask families verified to match, comparing
694 	 * the masks also validates the address's families match.
695 	 */
696 	if (!SOCK_EQ(a_mask, b_mask))
697 		return FALSE;
698 
699 	if (IS_IPV6(a)) {
700 		loops = sizeof(NSRCADR6(a)) / sizeof(*pa);
701 		pa = (const void *)&NSRCADR6(a);
702 		pb = (const void *)&NSRCADR6(b);
703 		pm = (const void *)&NSRCADR6(a_mask);
704 	} else {
705 		loops = sizeof(NSRCADR(a)) / sizeof(*pa);
706 		pa = (const void *)&NSRCADR(a);
707 		pb = (const void *)&NSRCADR(b);
708 		pm = (const void *)&NSRCADR(a_mask);
709 	}
710 	for (pa_limit = pa + loops; pa < pa_limit; pa++, pb++, pm++)
711 		if ((*pa & *pm) != (*pb & *pm))
712 			return FALSE;
713 
714 	return TRUE;
715 }
716 
717 
718 /*
719  * Code to tell if we have an IP address
720  * If we have then return the sockaddr structure
721  * and set the return value
722  * see the bind9/getaddresses.c for details
723  */
724 int
725 is_ip_address(
726 	const char *	host,
727 	u_short		af,
728 	sockaddr_u *	addr
729 	)
730 {
731 	struct in_addr in4;
732 	struct addrinfo hints;
733 	struct addrinfo *result;
734 	struct sockaddr_in6 *resaddr6;
735 	char tmpbuf[128];
736 	char *pch;
737 
738 	NTP_REQUIRE(host != NULL);
739 	NTP_REQUIRE(addr != NULL);
740 
741 	ZERO_SOCK(addr);
742 
743 	/*
744 	 * Try IPv4, then IPv6.  In order to handle the extended format
745 	 * for IPv6 scoped addresses (address%scope_ID), we'll use a local
746 	 * working buffer of 128 bytes.  The length is an ad-hoc value, but
747 	 * should be enough for this purpose; the buffer can contain a string
748 	 * of at least 80 bytes for scope_ID in addition to any IPv6 numeric
749 	 * addresses (up to 46 bytes), the delimiter character and the
750 	 * terminating NULL character.
751 	 */
752 	if (AF_UNSPEC == af || AF_INET == af)
753 		if (inet_pton(AF_INET, host, &in4) == 1) {
754 			AF(addr) = AF_INET;
755 			SET_ADDR4N(addr, in4.s_addr);
756 
757 			return TRUE;
758 		}
759 
760 	if (AF_UNSPEC == af || AF_INET6 == af)
761 		if (sizeof(tmpbuf) > strlen(host)) {
762 			if ('[' == host[0]) {
763 				strlcpy(tmpbuf, &host[1], sizeof(tmpbuf));
764 				pch = strchr(tmpbuf, ']');
765 				if (pch != NULL)
766 					*pch = '\0';
767 			} else {
768 				strlcpy(tmpbuf, host, sizeof(tmpbuf));
769 			}
770 			ZERO(hints);
771 			hints.ai_family = AF_INET6;
772 			hints.ai_flags |= AI_NUMERICHOST;
773 			if (getaddrinfo(tmpbuf, NULL, &hints, &result) == 0) {
774 				AF(addr) = AF_INET6;
775 				resaddr6 = (struct sockaddr_in6 *)result->ai_addr;
776 				SET_ADDR6N(addr, resaddr6->sin6_addr);
777 				SET_SCOPE(addr, resaddr6->sin6_scope_id);
778 
779 				freeaddrinfo(result);
780 				return TRUE;
781 			}
782 		}
783 	/*
784 	 * If we got here it was not an IP address
785 	 */
786 	return FALSE;
787 }
788 
789 
790 /*
791  * interface list enumerator - visitor pattern
792  */
793 void
794 interface_enumerate(
795 	interface_receiver_t	receiver,
796 	void *			data
797 	)
798 {
799 	interface_info_t ifi;
800 
801 	ifi.action = IFS_EXISTS;
802 	for (ifi.ep = ep_list; ifi.ep != NULL; ifi.ep = ifi.ep->elink)
803 		(*receiver)(data, &ifi);
804 }
805 
806 /*
807  * do standard initialization of interface structure
808  */
809 static void
810 init_interface(
811 	endpt *ep
812 	)
813 {
814 	ZERO(*ep);
815 	ep->fd = INVALID_SOCKET;
816 	ep->bfd = INVALID_SOCKET;
817 	ep->phase = sys_interphase;
818 }
819 
820 
821 /*
822  * create new interface structure initialize from
823  * template structure or via standard initialization
824  * function
825  */
826 static struct interface *
827 new_interface(
828 	struct interface *interface
829 	)
830 {
831 	struct interface *	iface;
832 
833 	iface = emalloc(sizeof(*iface));
834 
835 	if (NULL == interface)
836 		init_interface(iface);
837 	else				/* use the template */
838 		memcpy(iface, interface, sizeof(*iface));
839 
840 	/* count every new instance of an interface in the system */
841 	iface->ifnum = sys_ifnum++;
842 	iface->starttime = current_time;
843 
844 	return iface;
845 }
846 
847 
848 /*
849  * return interface storage into free memory pool
850  */
851 static inline void
852 delete_interface(
853 	endpt *ep
854 	)
855 {
856 	free(ep);
857 }
858 
859 
860 /*
861  * link interface into list of known interfaces
862  */
863 static void
864 add_interface(
865 	endpt *	ep
866 	)
867 {
868 	endpt **	pmclisthead;
869 	endpt *		scan;
870 	endpt *		scan_next;
871 	endpt *		unlinked;
872 	sockaddr_u *	addr;
873 	int		ep_local;
874 	int		scan_local;
875 	int		same_subnet;
876 	int		ep_univ_iid;	/* iface ID from MAC address */
877 	int		scan_univ_iid;	/* see RFC 4291 */
878 	int		ep_privacy;	/* random local iface ID */
879 	int		scan_privacy;	/* see RFC 4941 */
880 	int		rc;
881 
882 	/* Calculate the refid */
883 	ep->addr_refid = addr2refid(&ep->sin);
884 	/* link at tail so ntpdc -c ifstats index increases each row */
885 	LINK_TAIL_SLIST(ep_list, ep, elink, endpt);
886 	ninterfaces++;
887 #ifdef MCAST
888 	/* the rest is for enabled multicast-capable addresses only */
889 	if (ep->ignore_packets || !(INT_MULTICAST & ep->flags) ||
890 	    INT_LOOPBACK & ep->flags)
891 		return;
892 # ifndef INCLUDE_IPV6_MULTICAST_SUPPORT
893 	if (AF_INET6 == ep->family)
894 		return;
895 # endif
896 	pmclisthead = (AF_INET == ep->family)
897 			 ? &mc4_list
898 			 : &mc6_list;
899 
900 	if (AF_INET6 == ep->family) {
901 		ep_local =
902 		    IN6_IS_ADDR_LINKLOCAL(PSOCK_ADDR6(&ep->sin)) ||
903 		    IN6_IS_ADDR_SITELOCAL(PSOCK_ADDR6(&ep->sin));
904 		ep_univ_iid = IS_IID_UNIV(&ep->sin);
905 		ep_privacy = !!(INT_PRIVACY & ep->flags);
906 	} else {
907 		ep_local = FALSE;
908 		ep_univ_iid = FALSE;
909 		ep_privacy = FALSE;
910 	}
911 	DPRINTF(4, ("add_interface mcast-capable %s%s%s%s\n",
912 		    stoa(&ep->sin),
913 		    (ep_local) ? " link/scope-local" : "",
914 		    (ep_univ_iid) ? " univ-IID" : "",
915 		    (ep_privacy) ? " privacy" : ""));
916 	/*
917 	 * If we have multiple local addresses on the same network
918 	 * interface, and some are link- or site-local, do not multicast
919 	 * out from the link-/site-local addresses by default, to avoid
920 	 * duplicate manycastclient associations between v6 peers using
921 	 * link-local and global addresses.  link-local can still be
922 	 * chosen using "nic ignore myv6globalprefix::/64".
923 	 * Similarly, if we have multiple global addresses from the same
924 	 * prefix on the same network interface, multicast from one,
925 	 * preferring EUI-64, then static, then least RFC 4941 privacy
926 	 * addresses.
927 	 */
928 	for (scan = *pmclisthead; scan != NULL; scan = scan_next) {
929 		scan_next = scan->mclink;
930 		if (ep->family != scan->family)
931 			continue;
932 		if (strcmp(ep->name, scan->name))
933 			continue;
934 		same_subnet = addr_samesubnet(&ep->sin, &ep->mask,
935 					      &scan->sin, &scan->mask);
936 		if (AF_INET6 == ep->family) {
937 			addr = &scan->sin;
938 			scan_local =
939 			    IN6_IS_ADDR_LINKLOCAL(PSOCK_ADDR6(addr)) ||
940 			    IN6_IS_ADDR_SITELOCAL(PSOCK_ADDR6(addr));
941 			scan_univ_iid = IS_IID_UNIV(addr);
942 			scan_privacy = !!(INT_PRIVACY & scan->flags);
943 		} else {
944 			scan_local = FALSE;
945 			scan_univ_iid = FALSE;
946 			scan_privacy = FALSE;
947 		}
948 		DPRINTF(4, ("add_interface mcast-capable scan %s%s%s%s\n",
949 			    stoa(&scan->sin),
950 			    (scan_local) ? " link/scope-local" : "",
951 			    (scan_univ_iid) ? " univ-IID" : "",
952 			    (scan_privacy) ? " privacy" : ""));
953 		if ((ep_local && !scan_local) || (same_subnet &&
954 		    ((ep_privacy && !scan_privacy) ||
955 		     (!ep_univ_iid && scan_univ_iid)))) {
956 			DPRINTF(4, ("did not add %s to %s of IPv6 multicast-capable list which already has %s\n",
957 				stoa(&ep->sin),
958 				(ep_local)
959 				    ? "tail"
960 				    : "head",
961 				stoa(&scan->sin)));
962 			return;
963 		}
964 		if ((scan_local && !ep_local) || (same_subnet &&
965 		    ((scan_privacy && !ep_privacy) ||
966 		     (!scan_univ_iid && ep_univ_iid)))) {
967 			UNLINK_SLIST(unlinked, *pmclisthead,
968 				     scan, mclink, endpt);
969 			DPRINTF(4, ("%s %s from IPv6 multicast-capable list to add %s\n",
970 				(unlinked != scan)
971 				    ? "Failed to remove"
972 				    : "removed",
973 				stoa(&scan->sin), stoa(&ep->sin)));
974 		}
975 	}
976 	/*
977 	 * Add link/site local at the tail of the multicast-
978 	 * capable unicast interfaces list, so that ntpd will
979 	 * send from global addresses before link-/site-local
980 	 * ones.
981 	 */
982 	if (ep_local)
983 		LINK_TAIL_SLIST(*pmclisthead, ep, mclink, endpt);
984 	else
985 		LINK_SLIST(*pmclisthead, ep, mclink);
986 	DPRINTF(4, ("added %s to %s of IPv%s multicast-capable unicast local address list\n",
987 		stoa(&ep->sin),
988 		(ep_local)
989 		    ? "tail"
990 		    : "head",
991 		(AF_INET == ep->family)
992 		    ? "4"
993 		    : "6"));
994 
995 	if (INVALID_SOCKET == ep->fd)
996 		return;
997 
998 	/*
999 	 * select the local address from which to send to multicast.
1000 	 */
1001 	switch (AF(&ep->sin)) {
1002 
1003 	case AF_INET :
1004 		rc = setsockopt(ep->fd, IPPROTO_IP,
1005 				IP_MULTICAST_IF,
1006 				(void *)&NSRCADR(&ep->sin),
1007 				sizeof(NSRCADR(&ep->sin)));
1008 		if (rc)
1009 			msyslog(LOG_ERR,
1010 				"setsockopt IP_MULTICAST_IF %s fails: %m",
1011 				stoa(&ep->sin));
1012 		break;
1013 
1014 # ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
1015 	case AF_INET6 :
1016 		rc = setsockopt(ep->fd, IPPROTO_IPV6,
1017 				 IPV6_MULTICAST_IF,
1018 				 (void *)&ep->ifindex,
1019 				 sizeof(ep->ifindex));
1020 		/* do not complain if bound addr scope is ifindex */
1021 		if (rc && ep->ifindex != SCOPE(&ep->sin))
1022 			msyslog(LOG_ERR,
1023 				"setsockopt IPV6_MULTICAST_IF %u for %s fails: %m",
1024 				ep->ifindex, stoa(&ep->sin));
1025 		break;
1026 # endif
1027 	}
1028 #endif	/* MCAST */
1029 }
1030 
1031 
1032 /*
1033  * remove interface from known interface list and clean up
1034  * associated resources
1035  */
1036 static void
1037 remove_interface(
1038 	endpt *	ep
1039 	)
1040 {
1041 	endpt *		unlinked;
1042 	endpt **	pmclisthead;
1043 	sockaddr_u	resmask;
1044 
1045 	UNLINK_SLIST(unlinked, ep_list, ep, elink, endpt);
1046 	if (!ep->ignore_packets && INT_MULTICAST & ep->flags) {
1047 		pmclisthead = (AF_INET == ep->family)
1048 				 ? &mc4_list
1049 				 : &mc6_list;
1050 		UNLINK_SLIST(unlinked, *pmclisthead, ep, mclink, endpt);
1051 		DPRINTF(4, ("%s %s IPv%s multicast-capable unicast local address list\n",
1052 			stoa(&ep->sin),
1053 			(unlinked != NULL)
1054 			    ? "removed from"
1055 			    : "not found on",
1056 			(AF_INET == ep->family)
1057 			    ? "4"
1058 			    : "6"));
1059 	}
1060 	delete_interface_from_list(ep);
1061 
1062 	if (ep->fd != INVALID_SOCKET) {
1063 		msyslog(LOG_INFO,
1064 			"Deleting interface #%d %s, %s#%d, interface stats: received=%ld, sent=%ld, dropped=%ld, active_time=%ld secs",
1065 			ep->ifnum,
1066 			ep->name,
1067 			stoa(&ep->sin),
1068 			SRCPORT(&ep->sin),
1069 			ep->received,
1070 			ep->sent,
1071 			ep->notsent,
1072 			current_time - ep->starttime);
1073 		close_and_delete_fd_from_list(ep->fd);
1074 		ep->fd = INVALID_SOCKET;
1075 	}
1076 
1077 	if (ep->bfd != INVALID_SOCKET) {
1078 		msyslog(LOG_INFO,
1079 			"stop listening for broadcasts to %s on interface #%d %s",
1080 			stoa(&ep->bcast), ep->ifnum, ep->name);
1081 		close_and_delete_fd_from_list(ep->bfd);
1082 		ep->bfd = INVALID_SOCKET;
1083 		ep->flags &= ~INT_BCASTOPEN;
1084 	}
1085 
1086 	ninterfaces--;
1087 	mon_clearinterface(ep);
1088 
1089 	/* remove restrict interface entry */
1090 	SET_HOSTMASK(&resmask, AF(&ep->sin));
1091 	hack_restrict(RESTRICT_REMOVEIF, &ep->sin, &resmask,
1092 		      RESM_NTPONLY | RESM_INTERFACE, RES_IGNORE, 0);
1093 }
1094 
1095 
1096 static void
1097 log_listen_address(
1098 	endpt *	ep
1099 	)
1100 {
1101 	msyslog(LOG_INFO, "%s on %d %s %s",
1102 		(ep->ignore_packets)
1103 		    ? "Listen and drop"
1104 		    : "Listen normally",
1105 		ep->ifnum,
1106 		ep->name,
1107 		sptoa(&ep->sin));
1108 }
1109 
1110 
1111 static void
1112 create_wildcards(
1113 	u_short	port
1114 	)
1115 {
1116 	int			v4wild;
1117 #ifdef INCLUDE_IPV6_SUPPORT
1118 	int			v6wild;
1119 #endif
1120 	sockaddr_u		wildaddr;
1121 	nic_rule_action		action;
1122 	struct interface *	wildif;
1123 
1124 	/*
1125 	 * silence "potentially uninitialized" warnings from VC9
1126 	 * failing to follow the logic.  Ideally action could remain
1127 	 * uninitialized, and the memset be the first statement under
1128 	 * the first if (v4wild).
1129 	 */
1130 	action = ACTION_LISTEN;
1131 	ZERO(wildaddr);
1132 
1133 #ifdef INCLUDE_IPV6_SUPPORT
1134 	/*
1135 	 * create pseudo-interface with wildcard IPv6 address
1136 	 */
1137 	v6wild = ipv6_works;
1138 	if (v6wild) {
1139 		/* set wildaddr to the v6 wildcard address :: */
1140 		ZERO(wildaddr);
1141 		AF(&wildaddr) = AF_INET6;
1142 		SET_ADDR6N(&wildaddr, in6addr_any);
1143 		SET_PORT(&wildaddr, port);
1144 		SET_SCOPE(&wildaddr, 0);
1145 
1146 		/* check for interface/nic rules affecting the wildcard */
1147 		action = interface_action(NULL, &wildaddr, 0);
1148 		v6wild = (ACTION_IGNORE != action);
1149 	}
1150 	if (v6wild) {
1151 		wildif = new_interface(NULL);
1152 
1153 		strlcpy(wildif->name, "v6wildcard", sizeof(wildif->name));
1154 		memcpy(&wildif->sin, &wildaddr, sizeof(wildif->sin));
1155 		wildif->family = AF_INET6;
1156 		AF(&wildif->mask) = AF_INET6;
1157 		SET_ONESMASK(&wildif->mask);
1158 
1159 		wildif->flags = INT_UP | INT_WILDCARD;
1160 		wildif->ignore_packets = (ACTION_DROP == action);
1161 
1162 		wildif->fd = open_socket(&wildif->sin, 0, 1, wildif);
1163 
1164 		if (wildif->fd != INVALID_SOCKET) {
1165 			wildipv6 = wildif;
1166 			any6_interface = wildif;
1167 			add_addr_to_list(&wildif->sin, wildif);
1168 			add_interface(wildif);
1169 			log_listen_address(wildif);
1170 		} else {
1171 			msyslog(LOG_ERR,
1172 				"unable to bind to wildcard address %s - another process may be running - EXITING",
1173 				stoa(&wildif->sin));
1174 			exit(1);
1175 		}
1176 		DPRINT_INTERFACE(2, (wildif, "created ", "\n"));
1177 	}
1178 #endif
1179 
1180 	/*
1181 	 * create pseudo-interface with wildcard IPv4 address
1182 	 */
1183 	v4wild = ipv4_works;
1184 	if (v4wild) {
1185 		/* set wildaddr to the v4 wildcard address 0.0.0.0 */
1186 		AF(&wildaddr) = AF_INET;
1187 		SET_ADDR4N(&wildaddr, INADDR_ANY);
1188 		SET_PORT(&wildaddr, port);
1189 
1190 		/* check for interface/nic rules affecting the wildcard */
1191 		action = interface_action(NULL, &wildaddr, 0);
1192 		v4wild = (ACTION_IGNORE != action);
1193 	}
1194 	if (v4wild) {
1195 		wildif = new_interface(NULL);
1196 
1197 		strlcpy(wildif->name, "v4wildcard", sizeof(wildif->name));
1198 		memcpy(&wildif->sin, &wildaddr, sizeof(wildif->sin));
1199 		wildif->family = AF_INET;
1200 		AF(&wildif->mask) = AF_INET;
1201 		SET_ONESMASK(&wildif->mask);
1202 
1203 		wildif->flags = INT_BROADCAST | INT_UP | INT_WILDCARD;
1204 		wildif->ignore_packets = (ACTION_DROP == action);
1205 #if defined(MCAST)
1206 		/*
1207 		 * enable multicast reception on the broadcast socket
1208 		 */
1209 		AF(&wildif->bcast) = AF_INET;
1210 		SET_ADDR4N(&wildif->bcast, INADDR_ANY);
1211 		SET_PORT(&wildif->bcast, port);
1212 #endif /* MCAST */
1213 		wildif->fd = open_socket(&wildif->sin, 0, 1, wildif);
1214 
1215 		if (wildif->fd != INVALID_SOCKET) {
1216 			wildipv4 = wildif;
1217 			any_interface = wildif;
1218 
1219 			add_addr_to_list(&wildif->sin, wildif);
1220 			add_interface(wildif);
1221 			log_listen_address(wildif);
1222 		} else {
1223 			msyslog(LOG_ERR,
1224 				"unable to bind to wildcard address %s - another process may be running - EXITING",
1225 				stoa(&wildif->sin));
1226 			exit(1);
1227 		}
1228 		DPRINT_INTERFACE(2, (wildif, "created ", "\n"));
1229 	}
1230 }
1231 
1232 
1233 /*
1234  * add_nic_rule() -- insert a rule entry at the head of nic_rule_list.
1235  */
1236 void
1237 add_nic_rule(
1238 	nic_rule_match	match_type,
1239 	const char *	if_name,	/* interface name or numeric address */
1240 	int		prefixlen,
1241 	nic_rule_action	action
1242 	)
1243 {
1244 	nic_rule *	rule;
1245 	isc_boolean_t	is_ip;
1246 
1247 	rule = emalloc_zero(sizeof(*rule));
1248 	rule->match_type = match_type;
1249 	rule->prefixlen = prefixlen;
1250 	rule->action = action;
1251 
1252 	if (MATCH_IFNAME == match_type) {
1253 		NTP_REQUIRE(NULL != if_name);
1254 		rule->if_name = estrdup(if_name);
1255 	} else if (MATCH_IFADDR == match_type) {
1256 		NTP_REQUIRE(NULL != if_name);
1257 		/* set rule->addr */
1258 		is_ip = is_ip_address(if_name, AF_UNSPEC, &rule->addr);
1259 		NTP_REQUIRE(is_ip);
1260 	} else
1261 		NTP_REQUIRE(NULL == if_name);
1262 
1263 	LINK_SLIST(nic_rule_list, rule, next);
1264 }
1265 
1266 
1267 #ifdef DEBUG
1268 static const char *
1269 action_text(
1270 	nic_rule_action	action
1271 	)
1272 {
1273 	const char *t;
1274 
1275 	switch (action) {
1276 
1277 	default:
1278 		t = "ERROR";	/* quiet uninit warning */
1279 		DPRINTF(1, ("fatal: unknown nic_rule_action %d\n",
1280 			    action));
1281 		NTP_ENSURE(0);
1282 		break;
1283 
1284 	case ACTION_LISTEN:
1285 		t = "listen";
1286 		break;
1287 
1288 	case ACTION_IGNORE:
1289 		t = "ignore";
1290 		break;
1291 
1292 	case ACTION_DROP:
1293 		t = "drop";
1294 		break;
1295 	}
1296 
1297 	return t;
1298 }
1299 #endif	/* DEBUG */
1300 
1301 
1302 static nic_rule_action
1303 interface_action(
1304 	char *		if_name,
1305 	sockaddr_u *	if_addr,
1306 	u_int32		if_flags
1307 	)
1308 {
1309 	nic_rule *	rule;
1310 	int		isloopback;
1311 	int		iswildcard;
1312 
1313 	DPRINTF(4, ("interface_action: interface %s ",
1314 		    (if_name != NULL) ? if_name : "wildcard"));
1315 
1316 	iswildcard = is_wildcard_addr(if_addr);
1317 	isloopback = !!(INT_LOOPBACK & if_flags);
1318 
1319 	/*
1320 	 * Find any matching NIC rule from --interface / -I or ntp.conf
1321 	 * interface/nic rules.
1322 	 */
1323 	for (rule = nic_rule_list; rule != NULL; rule = rule->next) {
1324 
1325 		switch (rule->match_type) {
1326 
1327 		case MATCH_ALL:
1328 			/* loopback and wildcard excluded from "all" */
1329 			if (isloopback || iswildcard)
1330 				break;
1331 			DPRINTF(4, ("nic all %s\n",
1332 			    action_text(rule->action)));
1333 			return rule->action;
1334 
1335 		case MATCH_IPV4:
1336 			if (IS_IPV4(if_addr)) {
1337 				DPRINTF(4, ("nic ipv4 %s\n",
1338 				    action_text(rule->action)));
1339 				return rule->action;
1340 			}
1341 			break;
1342 
1343 		case MATCH_IPV6:
1344 			if (IS_IPV6(if_addr)) {
1345 				DPRINTF(4, ("nic ipv6 %s\n",
1346 				    action_text(rule->action)));
1347 				return rule->action;
1348 			}
1349 			break;
1350 
1351 		case MATCH_WILDCARD:
1352 			if (iswildcard) {
1353 				DPRINTF(4, ("nic wildcard %s\n",
1354 				    action_text(rule->action)));
1355 				return rule->action;
1356 			}
1357 			break;
1358 
1359 		case MATCH_IFADDR:
1360 			if (rule->prefixlen != -1) {
1361 				if (addr_eqprefix(if_addr, &rule->addr,
1362 						  rule->prefixlen)) {
1363 
1364 					DPRINTF(4, ("subnet address match - %s\n",
1365 					    action_text(rule->action)));
1366 					return rule->action;
1367 				}
1368 			} else
1369 				if (SOCK_EQ(if_addr, &rule->addr)) {
1370 
1371 					DPRINTF(4, ("address match - %s\n",
1372 					    action_text(rule->action)));
1373 					return rule->action;
1374 				}
1375 			break;
1376 
1377 		case MATCH_IFNAME:
1378 			if (if_name != NULL
1379 #if defined(HAVE_FNMATCH) && defined(FNM_CASEFOLD)
1380 			    && !fnmatch(rule->if_name, if_name, FNM_CASEFOLD)
1381 #else
1382 			    && !strcasecmp(if_name, rule->if_name)
1383 #endif
1384 			    ) {
1385 
1386 				DPRINTF(4, ("interface name match - %s\n",
1387 				    action_text(rule->action)));
1388 				return rule->action;
1389 			}
1390 			break;
1391 		}
1392 	}
1393 
1394 	/*
1395 	 * Unless explicitly disabled such as with "nic ignore ::1"
1396 	 * listen on loopback addresses.  Since ntpq and ntpdc query
1397 	 * "localhost" by default, which typically resolves to ::1 and
1398 	 * 127.0.0.1, it's useful to default to listening on both.
1399 	 */
1400 	if (isloopback) {
1401 		DPRINTF(4, ("default loopback listen\n"));
1402 		return ACTION_LISTEN;
1403 	}
1404 
1405 	/*
1406 	 * Treat wildcard addresses specially.  If there is no explicit
1407 	 * "nic ... wildcard" or "nic ... 0.0.0.0" or "nic ... ::" rule
1408 	 * default to drop.
1409 	 */
1410 	if (iswildcard) {
1411 		DPRINTF(4, ("default wildcard drop\n"));
1412 		return ACTION_DROP;
1413 	}
1414 
1415 	/*
1416 	 * Check for "virtual IP" (colon in the interface name) after
1417 	 * the rules so that "ntpd --interface eth0:1 -novirtualips"
1418 	 * does indeed listen on eth0:1's addresses.
1419 	 */
1420 	if (!listen_to_virtual_ips && if_name != NULL
1421 	    && (strchr(if_name, ':') != NULL)) {
1422 
1423 		DPRINTF(4, ("virtual ip - ignore\n"));
1424 		return ACTION_IGNORE;
1425 	}
1426 
1427 	/*
1428 	 * If there are no --interface/-I command-line options and no
1429 	 * interface/nic rules in ntp.conf, the default action is to
1430 	 * listen.  In the presence of rules from either, the default
1431 	 * is to ignore.  This implements ntpd's traditional listen-
1432 	 * every default with no interface listen configuration, and
1433 	 * ensures a single -I eth0 or "nic listen eth0" means do not
1434 	 * listen on any other addresses.
1435 	 */
1436 	if (NULL == nic_rule_list) {
1437 		DPRINTF(4, ("default listen\n"));
1438 		return ACTION_LISTEN;
1439 	}
1440 
1441 	DPRINTF(4, ("implicit ignore\n"));
1442 	return ACTION_IGNORE;
1443 }
1444 
1445 
1446 static void
1447 convert_isc_if(
1448 	isc_interface_t *isc_if,
1449 	endpt *itf,
1450 	u_short port
1451 	)
1452 {
1453 	const u_char v6loop[16] = {0, 0, 0, 0, 0, 0, 0, 0,
1454 				   0, 0, 0, 0, 0, 0, 0, 1};
1455 
1456 	strlcpy(itf->name, isc_if->name, sizeof(itf->name));
1457 	itf->ifindex = isc_if->ifindex;
1458 	itf->family = (u_short)isc_if->af;
1459 	AF(&itf->sin) = itf->family;
1460 	AF(&itf->mask) = itf->family;
1461 	AF(&itf->bcast) = itf->family;
1462 	SET_PORT(&itf->sin, port);
1463 	SET_PORT(&itf->mask, port);
1464 	SET_PORT(&itf->bcast, port);
1465 
1466 	if (IS_IPV4(&itf->sin)) {
1467 		NSRCADR(&itf->sin) = isc_if->address.type.in.s_addr;
1468 		NSRCADR(&itf->mask) = isc_if->netmask.type.in.s_addr;
1469 
1470 		if (isc_if->flags & INTERFACE_F_BROADCAST) {
1471 			itf->flags |= INT_BROADCAST;
1472 			NSRCADR(&itf->bcast) =
1473 			    isc_if->broadcast.type.in.s_addr;
1474 		}
1475 	}
1476 #ifdef INCLUDE_IPV6_SUPPORT
1477 	else if (IS_IPV6(&itf->sin)) {
1478 		SET_ADDR6N(&itf->sin, isc_if->address.type.in6);
1479 		SET_ADDR6N(&itf->mask, isc_if->netmask.type.in6);
1480 
1481 		SET_SCOPE(&itf->sin, isc_if->address.zone);
1482 	}
1483 #endif /* INCLUDE_IPV6_SUPPORT */
1484 
1485 
1486 	/* Process the rest of the flags */
1487 
1488 	itf->flags |=
1489 		  ((INTERFACE_F_UP & isc_if->flags)
1490 			? INT_UP : 0)
1491 		| ((INTERFACE_F_LOOPBACK & isc_if->flags)
1492 			? INT_LOOPBACK : 0)
1493 		| ((INTERFACE_F_POINTTOPOINT & isc_if->flags)
1494 			? INT_PPP : 0)
1495 		| ((INTERFACE_F_MULTICAST & isc_if->flags)
1496 			? INT_MULTICAST : 0)
1497 		| ((INTERFACE_F_PRIVACY & isc_if->flags)
1498 			? INT_PRIVACY : 0)
1499 		;
1500 
1501 	/*
1502 	 * Clear the loopback flag if the address is not localhost.
1503 	 * http://bugs.ntp.org/1683
1504 	 */
1505 	if (INT_LOOPBACK & itf->flags) {
1506 		if (AF_INET == itf->family) {
1507 			if (127 != (SRCADR(&itf->sin) >> 24))
1508 				itf->flags &= ~INT_LOOPBACK;
1509 		} else {
1510 			if (memcmp(v6loop, NSRCADR6(&itf->sin),
1511 				   sizeof(NSRCADR6(&itf->sin))))
1512 				itf->flags &= ~INT_LOOPBACK;
1513 		}
1514 	}
1515 }
1516 
1517 
1518 /*
1519  * refresh_interface
1520  *
1521  * some OSes have been observed to keep
1522  * cached routes even when more specific routes
1523  * become available.
1524  * this can be mitigated by re-binding
1525  * the socket.
1526  */
1527 static int
1528 refresh_interface(
1529 	struct interface * interface
1530 	)
1531 {
1532 #ifdef  OS_MISSES_SPECIFIC_ROUTE_UPDATES
1533 	if (interface->fd != INVALID_SOCKET) {
1534 		int bcast = (interface->flags & INT_BCASTXMIT) != 0;
1535 		/* as we forcibly close() the socket remove the
1536 		   broadcast permission indication */
1537 		if (bcast)
1538 			socket_broadcast_disable(interface, &interface->sin);
1539 
1540 		close_and_delete_fd_from_list(interface->fd);
1541 
1542 		/* create new socket picking up a new first hop binding
1543 		   at connect() time */
1544 		interface->fd = open_socket(&interface->sin,
1545 					    bcast, 0, interface);
1546 		 /*
1547 		  * reset TTL indication so TTL is is set again
1548 		  * next time around
1549 		  */
1550 		interface->last_ttl = 0;
1551 		return (interface->fd != INVALID_SOCKET);
1552 	} else
1553 		return 0;	/* invalid sockets are not refreshable */
1554 #else /* !OS_MISSES_SPECIFIC_ROUTE_UPDATES */
1555 	return (interface->fd != INVALID_SOCKET);
1556 #endif /* !OS_MISSES_SPECIFIC_ROUTE_UPDATES */
1557 }
1558 
1559 /*
1560  * interface_update - externally callable update function
1561  */
1562 void
1563 interface_update(
1564 	interface_receiver_t	receiver,
1565 	void *			data)
1566 {
1567 	int new_interface_found;
1568 
1569 	if (disable_dynamic_updates)
1570 		return;
1571 
1572 	BLOCKIO();
1573 	new_interface_found = update_interfaces(NTP_PORT, receiver, data);
1574 	UNBLOCKIO();
1575 
1576 	if (!new_interface_found)
1577 		return;
1578 
1579 #ifdef DEBUG
1580 	msyslog(LOG_DEBUG, "new interface(s) found: waking up resolver");
1581 #endif
1582 	interrupt_worker_sleep();
1583 }
1584 
1585 
1586 /*
1587  * sau_from_netaddr() - convert network address on-wire formats.
1588  * Convert from libisc's isc_netaddr_t to NTP's sockaddr_u
1589  */
1590 void
1591 sau_from_netaddr(
1592 	sockaddr_u *psau,
1593 	const isc_netaddr_t *pna
1594 	)
1595 {
1596 	ZERO_SOCK(psau);
1597 	AF(psau) = (u_short)pna->family;
1598 	switch (pna->family) {
1599 
1600 	case AF_INET:
1601 		memcpy(&psau->sa4.sin_addr, &pna->type.in,
1602 		       sizeof(psau->sa4.sin_addr));
1603 		break;
1604 
1605 	case AF_INET6:
1606 		memcpy(&psau->sa6.sin6_addr, &pna->type.in6,
1607 		       sizeof(psau->sa6.sin6_addr));
1608 		break;
1609 	}
1610 }
1611 
1612 
1613 static int
1614 is_wildcard_addr(
1615 	const sockaddr_u *psau
1616 	)
1617 {
1618 	if (IS_IPV4(psau) && !NSRCADR(psau))
1619 		return 1;
1620 
1621 #ifdef INCLUDE_IPV6_SUPPORT
1622 	if (IS_IPV6(psau) && S_ADDR6_EQ(psau, &in6addr_any))
1623 		return 1;
1624 #endif
1625 
1626 	return 0;
1627 }
1628 
1629 
1630 #ifdef OS_NEEDS_REUSEADDR_FOR_IFADDRBIND
1631 /*
1632  * enable/disable re-use of wildcard address socket
1633  */
1634 static void
1635 set_wildcard_reuse(
1636 	u_short	family,
1637 	int	on
1638 	)
1639 {
1640 	struct interface *any;
1641 	SOCKET fd = INVALID_SOCKET;
1642 
1643 	any = ANY_INTERFACE_BYFAM(family);
1644 	if (any != NULL)
1645 		fd = any->fd;
1646 
1647 	if (fd != INVALID_SOCKET) {
1648 		if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
1649 			       (char *)&on, sizeof(on)))
1650 			msyslog(LOG_ERR,
1651 				"set_wildcard_reuse: setsockopt(SO_REUSEADDR, %s) failed: %m",
1652 				on ? "on" : "off");
1653 
1654 		DPRINTF(4, ("set SO_REUSEADDR to %s on %s\n",
1655 			    on ? "on" : "off",
1656 			    stoa(&any->sin)));
1657 	}
1658 }
1659 #endif /* OS_NEEDS_REUSEADDR_FOR_IFADDRBIND */
1660 
1661 
1662 static isc_boolean_t
1663 check_flags6(
1664 	sockaddr_u *psau,
1665 	const char *name,
1666 	u_int32 flags6
1667 	)
1668 {
1669 #if defined(INCLUDE_IPV6_SUPPORT) && defined(SIOCGIFAFLAG_IN6) && \
1670     (defined(IN6_IFF_ANYCAST) || defined(IN6_IFF_NOTREADY))
1671 	struct in6_ifreq ifr6;
1672 	int fd;
1673 	u_int32 exclude = 0;
1674 
1675 	if (psau->sa.sa_family != AF_INET6)
1676 		return ISC_FALSE;
1677 	if ((fd = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
1678 		return ISC_FALSE;
1679 	ZERO(ifr6);
1680 	memcpy(&ifr6.ifr_addr, &psau->sa6, sizeof(ifr6.ifr_addr));
1681 	strlcpy(ifr6.ifr_name, name, sizeof(ifr6.ifr_name));
1682 	if (ioctl(fd, SIOCGIFAFLAG_IN6, &ifr6) < 0) {
1683 		close(fd);
1684 		return ISC_FALSE;
1685 	}
1686 	close(fd);
1687 	flags6 = ifr6.ifr_ifru.ifru_flags6;
1688 #if defined(IN6_IFF_ANYCAST)
1689 	exclude |= IN6_IFF_ANYCAST;
1690 #endif /* !IN6_IFF_ANYCAST */
1691 #if defined(IN6_IFF_NOTREADY)
1692 	exclude |= IN6_IFF_NOTREADY;
1693 #endif /* !IN6_IFF_NOTREADY */
1694 	if ((flags6 & exclude) != 0)
1695 		return ISC_TRUE;
1696 #endif	/* INCLUDE_IPV6_SUPPORT && SIOCGIFAFLAG_IN6 && (IN6_IFF_ANYCAST && IN6_IFF_NOTREADY) */
1697 	return ISC_FALSE;
1698 }
1699 
1700 static isc_boolean_t
1701 is_not_bindable(
1702 	sockaddr_u *psau,
1703 	const char *name
1704 	)
1705 {
1706 #ifdef IN6_IFF_ANYCAST
1707 	return check_flags6(psau, name, IN6_IFF_ANYCAST);
1708 #else
1709 	return ISC_FALSE;
1710 #endif
1711 }
1712 
1713 static isc_boolean_t
1714 is_valid(
1715 	sockaddr_u *psau,
1716 	const char *name
1717 	)
1718 {
1719 	u_int32 flags6;
1720 
1721 	flags6 = 0;
1722 #ifdef IN6_IFF_DEPARTED
1723 	flags6 |= IN6_IFF_DEPARTED;
1724 #endif
1725 #ifdef IN6_IFF_DETACHED
1726 	flags6 |= IN6_IFF_DETACHED;
1727 #endif
1728 #ifdef IN6_IFF_TENTATIVE
1729 	flags6 |= IN6_IFF_TENTATIVE;
1730 #endif
1731 	return check_flags6(psau, name, flags6) ? ISC_FALSE : ISC_TRUE;
1732 }
1733 
1734 /*
1735  * update_interface strategy
1736  *
1737  * toggle configuration phase
1738  *
1739  * Phase 1:
1740  * forall currently existing interfaces
1741  *   if address is known:
1742  *	drop socket - rebind again
1743  *
1744  *   if address is NOT known:
1745  *	attempt to create a new interface entry
1746  *
1747  * Phase 2:
1748  * forall currently known non MCAST and WILDCARD interfaces
1749  *   if interface does not match configuration phase (not seen in phase 1):
1750  *	remove interface from known interface list
1751  *	forall peers associated with this interface
1752  *         disconnect peer from this interface
1753  *
1754  * Phase 3:
1755  *   attempt to re-assign interfaces to peers
1756  *
1757  */
1758 
1759 static int
1760 update_interfaces(
1761 	u_short			port,
1762 	interface_receiver_t	receiver,
1763 	void *			data
1764 	)
1765 {
1766 	isc_mem_t *		mctx = (void *)-1;
1767 	interface_info_t	ifi;
1768 	isc_interfaceiter_t *	iter;
1769 	isc_result_t		result;
1770 	isc_interface_t		isc_if;
1771 	int			new_interface_found;
1772 	unsigned int		family;
1773 	endpt			enumep;
1774 	endpt *			ep;
1775 	endpt *			next_ep;
1776 
1777 	DPRINTF(3, ("update_interfaces(%d)\n", port));
1778 
1779 	/*
1780 	 * phase one - scan interfaces
1781 	 * - create those that are not found
1782 	 * - update those that are found
1783 	 */
1784 
1785 	new_interface_found = FALSE;
1786 	iter = NULL;
1787 	result = isc_interfaceiter_create(mctx, &iter);
1788 
1789 	if (result != ISC_R_SUCCESS)
1790 		return 0;
1791 
1792 	/*
1793 	 * Toggle system interface scan phase to find untouched
1794 	 * interfaces to be deleted.
1795 	 */
1796 	sys_interphase ^= 0x1;
1797 
1798 	for (result = isc_interfaceiter_first(iter);
1799 	     ISC_R_SUCCESS == result;
1800 	     result = isc_interfaceiter_next(iter)) {
1801 
1802 		result = isc_interfaceiter_current(iter, &isc_if);
1803 
1804 		if (result != ISC_R_SUCCESS)
1805 			break;
1806 
1807 		/* See if we have a valid family to use */
1808 		family = isc_if.address.family;
1809 		if (AF_INET != family && AF_INET6 != family)
1810 			continue;
1811 		if (AF_INET == family && !ipv4_works)
1812 			continue;
1813 		if (AF_INET6 == family && !ipv6_works)
1814 			continue;
1815 
1816 		/* create prototype */
1817 		init_interface(&enumep);
1818 
1819 		convert_isc_if(&isc_if, &enumep, port);
1820 
1821 		DPRINT_INTERFACE(4, (&enumep, "examining ", "\n"));
1822 
1823 		/*
1824 		 * Check if and how we are going to use the interface.
1825 		 */
1826 		switch (interface_action(enumep.name, &enumep.sin,
1827 					 enumep.flags)) {
1828 
1829 		case ACTION_IGNORE:
1830 			DPRINTF(4, ("ignoring interface %s (%s) - by nic rules\n",
1831 				    enumep.name, stoa(&enumep.sin)));
1832 			continue;
1833 
1834 		case ACTION_LISTEN:
1835 			DPRINTF(4, ("listen interface %s (%s) - by nic rules\n",
1836 				    enumep.name, stoa(&enumep.sin)));
1837 			enumep.ignore_packets = ISC_FALSE;
1838 			break;
1839 
1840 		case ACTION_DROP:
1841 			DPRINTF(4, ("drop on interface %s (%s) - by nic rules\n",
1842 				    enumep.name, stoa(&enumep.sin)));
1843 			enumep.ignore_packets = ISC_TRUE;
1844 			break;
1845 		}
1846 
1847 		 /* interfaces must be UP to be usable */
1848 		if (!(enumep.flags & INT_UP)) {
1849 			DPRINTF(4, ("skipping interface %s (%s) - DOWN\n",
1850 				    enumep.name, stoa(&enumep.sin)));
1851 			continue;
1852 		}
1853 
1854 		/*
1855 		 * skip any interfaces UP and bound to a wildcard
1856 		 * address - some dhcp clients produce that in the
1857 		 * wild
1858 		 */
1859 		if (is_wildcard_addr(&enumep.sin))
1860 			continue;
1861 
1862 		if (is_not_bindable(&enumep.sin, isc_if.name))
1863 			continue;
1864 
1865 		/*
1866 		 * skip any address that is an invalid state to be used
1867 		 */
1868 		if (!is_valid(&enumep.sin, isc_if.name))
1869 			continue;
1870 
1871 		/*
1872 		 * map to local *address* in order to map all duplicate
1873 		 * interfaces to an endpt structure with the appropriate
1874 		 * socket.  Our name space is (ip-address), NOT
1875 		 * (interface name, ip-address).
1876 		 */
1877 		ep = getinterface(&enumep.sin, INT_WILDCARD);
1878 
1879 		if (ep != NULL && refresh_interface(ep)) {
1880 			/*
1881 			 * found existing and up to date interface -
1882 			 * mark present.
1883 			 */
1884 			if (ep->phase != sys_interphase) {
1885 				/*
1886 				 * On a new round we reset the name so
1887 				 * the interface name shows up again if
1888 				 * this address is no longer shared.
1889 				 * We reset ignore_packets from the
1890 				 * new prototype to respect any runtime
1891 				 * changes to the nic rules.
1892 				 */
1893 				strlcpy(ep->name, enumep.name,
1894 					sizeof(ep->name));
1895 				ep->ignore_packets =
1896 					    enumep.ignore_packets;
1897 			} else {
1898 				/* name collision - rename interface */
1899 				strlcpy(ep->name, "*multiple*",
1900 					sizeof(ep->name));
1901 			}
1902 
1903 			DPRINT_INTERFACE(4, (ep, "updating ",
1904 					     " present\n"));
1905 
1906 			if (ep->ignore_packets !=
1907 			    enumep.ignore_packets) {
1908 				/*
1909 				 * We have conflicting configurations
1910 				 * for the interface address. This is
1911 				 * caused by using -I <interfacename>
1912 				 * for an interface that shares its
1913 				 * address with other interfaces. We
1914 				 * can not disambiguate incoming
1915 				 * packets delivered to this socket
1916 				 * without extra syscalls/features.
1917 				 * These are not (commonly) available.
1918 				 * Note this is a more unusual
1919 				 * configuration where several
1920 				 * interfaces share an address but
1921 				 * filtering via interface name is
1922 				 * attempted.  We resolve the
1923 				 * configuration conflict by disabling
1924 				 * the processing of received packets.
1925 				 * This leads to no service on the
1926 				 * interface address where the conflict
1927 				 * occurs.
1928 				 */
1929 				msyslog(LOG_ERR,
1930 					"WARNING: conflicting enable configuration for interfaces %s and %s for address %s - unsupported configuration - address DISABLED",
1931 					enumep.name, ep->name,
1932 					stoa(&enumep.sin));
1933 
1934 				ep->ignore_packets = ISC_TRUE;
1935 			}
1936 
1937 			ep->phase = sys_interphase;
1938 
1939 			ifi.action = IFS_EXISTS;
1940 			ifi.ep = ep;
1941 			if (receiver != NULL)
1942 				(*receiver)(data, &ifi);
1943 		} else {
1944 			/*
1945 			 * This is new or refreshing failed - add to
1946 			 * our interface list.  If refreshing failed we
1947 			 * will delete the interface structure in phase
1948 			 * 2 as the interface was not marked current.
1949 			 * We can bind to the address as the refresh
1950 			 * code already closed the offending socket
1951 			 */
1952 			ep = create_interface(port, &enumep);
1953 
1954 			if (ep != NULL) {
1955 				ifi.action = IFS_CREATED;
1956 				ifi.ep = ep;
1957 				if (receiver != NULL)
1958 					(*receiver)(data, &ifi);
1959 
1960 				new_interface_found = TRUE;
1961 				DPRINT_INTERFACE(3,
1962 					(ep, "updating ",
1963 					 " new - created\n"));
1964 			} else {
1965 				DPRINT_INTERFACE(3,
1966 					(&enumep, "updating ",
1967 					 " new - creation FAILED"));
1968 
1969 				msyslog(LOG_INFO,
1970 					"failed to init interface for address %s",
1971 					stoa(&enumep.sin));
1972 				continue;
1973 			}
1974 		}
1975 	}
1976 
1977 	isc_interfaceiter_destroy(&iter);
1978 
1979 	/*
1980 	 * phase 2 - delete gone interfaces - reassigning peers to
1981 	 * other interfaces
1982 	 */
1983 	for (ep = ep_list; ep != NULL; ep = next_ep) {
1984 		next_ep = ep->elink;
1985 
1986 		/*
1987 		 * if phase does not match sys_phase this interface was
1988 		 * not enumerated during the last interface scan - so it
1989 		 * is gone and will be deleted here unless it did not
1990 		 * originate from interface enumeration (INT_WILDCARD,
1991 		 * INT_MCASTIF).
1992 		 */
1993 		if (((INT_WILDCARD | INT_MCASTIF) & ep->flags) ||
1994 		    ep->phase == sys_interphase)
1995 			continue;
1996 
1997 		DPRINT_INTERFACE(3, (ep, "updating ",
1998 				     "GONE - deleting\n"));
1999 		remove_interface(ep);
2000 
2001 		ifi.action = IFS_DELETED;
2002 		ifi.ep = ep;
2003 		if (receiver != NULL)
2004 			(*receiver)(data, &ifi);
2005 
2006 		/* disconnect peers from deleted endpt. */
2007 		while (ep->peers != NULL)
2008 			set_peerdstadr(ep->peers, NULL);
2009 
2010 		/*
2011 		 * update globals in case we lose
2012 		 * a loopback interface
2013 		 */
2014 		if (ep == loopback_interface)
2015 			loopback_interface = NULL;
2016 
2017 		delete_interface(ep);
2018 	}
2019 
2020 	/*
2021 	 * phase 3 - re-configure as the world has possibly changed
2022 	 *
2023 	 * never ever make this conditional again - it is needed to track
2024 	 * routing updates. see bug #2506
2025 	 */
2026 	refresh_all_peerinterfaces();
2027 
2028 	if (broadcast_client_enabled)
2029 		io_setbclient();
2030 
2031 	if (sys_bclient)
2032 		io_setbclient();
2033 
2034 	/*
2035 	 * Check multicast interfaces and try to join multicast groups if
2036          * not joined yet.
2037          */
2038 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2039 		remaddr_t *entry;
2040 
2041 		if (!(INT_MCASTIF & ep->flags) || (INT_MCASTOPEN & ep->flags))
2042 			continue;
2043 
2044 		/* Find remote address that was linked to this interface */
2045 		for (entry = remoteaddr_list;
2046 		     entry != NULL;
2047 		     entry = entry->link) {
2048 			if (entry->ep == ep) {
2049 				if (socket_multicast_enable(ep, &entry->addr)) {
2050 					msyslog(LOG_INFO,
2051 						"Joined %s socket to multicast group %s",
2052 						stoa(&ep->sin),
2053 						stoa(&entry->addr));
2054 				}
2055 				break;
2056 			}
2057 		}
2058 	}
2059 
2060 	return new_interface_found;
2061 }
2062 
2063 
2064 /*
2065  * create_sockets - create a socket for each interface plus a default
2066  *			socket for when we don't know where to send
2067  */
2068 static int
2069 create_sockets(
2070 	u_short port
2071 	)
2072 {
2073 #ifndef HAVE_IO_COMPLETION_PORT
2074 	/*
2075 	 * I/O Completion Ports don't care about the select and FD_SET
2076 	 */
2077 	maxactivefd = 0;
2078 	FD_ZERO(&activefds);
2079 #endif
2080 
2081 	DPRINTF(2, ("create_sockets(%d)\n", port));
2082 
2083 	create_wildcards(port);
2084 
2085 	update_interfaces(port, NULL, NULL);
2086 
2087 	/*
2088 	 * Now that we have opened all the sockets, turn off the reuse
2089 	 * flag for security.
2090 	 */
2091 	set_reuseaddr(0);
2092 
2093 	DPRINTF(2, ("create_sockets: Total interfaces = %d\n", ninterfaces));
2094 
2095 	return ninterfaces;
2096 }
2097 
2098 /*
2099  * create_interface - create a new interface for a given prototype
2100  *		      binding the socket.
2101  */
2102 static struct interface *
2103 create_interface(
2104 	u_short			port,
2105 	struct interface *	protot
2106 	)
2107 {
2108 	sockaddr_u	resmask;
2109 	endpt *		iface;
2110 #if defined(MCAST) && defined(MULTICAST_NONEWSOCKET)
2111 	remaddr_t *	entry;
2112 	remaddr_t *	next_entry;
2113 #endif
2114 	DPRINTF(2, ("create_interface(%s#%d)\n", stoa(&protot->sin),
2115 		    port));
2116 
2117 	/* build an interface */
2118 	iface = new_interface(protot);
2119 
2120 	/*
2121 	 * create socket
2122 	 */
2123 	iface->fd = open_socket(&iface->sin, 0, 0, iface);
2124 
2125 	if (iface->fd != INVALID_SOCKET)
2126 		log_listen_address(iface);
2127 
2128 	if ((INT_BROADCAST & iface->flags)
2129 	    && iface->bfd != INVALID_SOCKET)
2130 		msyslog(LOG_INFO, "Listening on broadcast address %s#%d",
2131 			stoa((&iface->bcast)), port);
2132 
2133 	if (INVALID_SOCKET == iface->fd
2134 	    && INVALID_SOCKET == iface->bfd) {
2135 		msyslog(LOG_ERR, "unable to create socket on %s (%d) for %s#%d",
2136 			iface->name,
2137 			iface->ifnum,
2138 			stoa((&iface->sin)),
2139 			port);
2140 		delete_interface(iface);
2141 		return NULL;
2142 	}
2143 
2144 	/*
2145 	 * Blacklist our own addresses, no use talking to ourself
2146 	 */
2147 	SET_HOSTMASK(&resmask, AF(&iface->sin));
2148 	hack_restrict(RESTRICT_FLAGS, &iface->sin, &resmask,
2149 		      RESM_NTPONLY | RESM_INTERFACE, RES_IGNORE, 0);
2150 
2151 	/*
2152 	 * set globals with the first found
2153 	 * loopback interface of the appropriate class
2154 	 */
2155 	if (NULL == loopback_interface && AF_INET == iface->family
2156 	    && (INT_LOOPBACK & iface->flags))
2157 		loopback_interface = iface;
2158 
2159 	/*
2160 	 * put into our interface list
2161 	 */
2162 	add_addr_to_list(&iface->sin, iface);
2163 	add_interface(iface);
2164 
2165 #if defined(MCAST) && defined(MULTICAST_NONEWSOCKET)
2166 	/*
2167 	 * Join any previously-configured compatible multicast groups.
2168 	 */
2169 	if (INT_MULTICAST & iface->flags &&
2170 	    !((INT_LOOPBACK | INT_WILDCARD) & iface->flags) &&
2171 	    !iface->ignore_packets) {
2172 		for (entry = remoteaddr_list;
2173 		     entry != NULL;
2174 		     entry = next_entry) {
2175 			next_entry = entry->link;
2176 			if (AF(&iface->sin) != AF(&entry->addr) ||
2177 			    !IS_MCAST(&entry->addr))
2178 				continue;
2179 			if (socket_multicast_enable(iface,
2180 						    &entry->addr))
2181 				msyslog(LOG_INFO,
2182 					"Joined %s socket to multicast group %s",
2183 					stoa(&iface->sin),
2184 					stoa(&entry->addr));
2185 			else
2186 				msyslog(LOG_ERR,
2187 					"Failed to join %s socket to multicast group %s",
2188 					stoa(&iface->sin),
2189 					stoa(&entry->addr));
2190 		}
2191 	}
2192 #endif	/* MCAST && MCAST_NONEWSOCKET */
2193 
2194 	DPRINT_INTERFACE(2, (iface, "created ", "\n"));
2195 	return iface;
2196 }
2197 
2198 
2199 #ifdef SO_EXCLUSIVEADDRUSE
2200 static void
2201 set_excladdruse(
2202 	SOCKET fd
2203 	)
2204 {
2205 	int one = 1;
2206 	int failed;
2207 #ifdef SYS_WINNT
2208 	DWORD err;
2209 #endif
2210 
2211 	failed = setsockopt(fd, SOL_SOCKET, SO_EXCLUSIVEADDRUSE,
2212 			    (char *)&one, sizeof(one));
2213 
2214 	if (!failed)
2215 		return;
2216 
2217 #ifdef SYS_WINNT
2218 	/*
2219 	 * Prior to Windows XP setting SO_EXCLUSIVEADDRUSE can fail with
2220 	 * error WSAINVAL depending on service pack level and whether
2221 	 * the user account is in the Administrators group.  Do not
2222 	 * complain if it fails that way on versions prior to XP (5.1).
2223 	 */
2224 	err = GetLastError();
2225 
2226 	if (isc_win32os_versioncheck(5, 1, 0, 0) < 0	/* < 5.1/XP */
2227 	    && WSAEINVAL == err)
2228 		return;
2229 
2230 	SetLastError(err);
2231 #endif
2232 	msyslog(LOG_ERR,
2233 		"setsockopt(%d, SO_EXCLUSIVEADDRUSE, on): %m",
2234 		(int)fd);
2235 }
2236 #endif  /* SO_EXCLUSIVEADDRUSE */
2237 
2238 
2239 /*
2240  * set_reuseaddr() - set/clear REUSEADDR on all sockets
2241  *			NB possible hole - should we be doing this on broadcast
2242  *			fd's also?
2243  */
2244 static void
2245 set_reuseaddr(
2246 	int flag
2247 	)
2248 {
2249 #ifndef SO_EXCLUSIVEADDRUSE
2250 	endpt *ep;
2251 
2252 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2253 		if (ep->flags & INT_WILDCARD)
2254 			continue;
2255 
2256 		/*
2257 		 * if ep->fd  is INVALID_SOCKET, we might have a adapter
2258 		 * configured but not present
2259 		 */
2260 		DPRINTF(4, ("setting SO_REUSEADDR on %.16s@%s to %s\n",
2261 			    ep->name, stoa(&ep->sin),
2262 			    flag ? "on" : "off"));
2263 
2264 		if (ep->fd != INVALID_SOCKET) {
2265 			if (setsockopt(ep->fd, SOL_SOCKET, SO_REUSEADDR,
2266 				       (char *)&flag, sizeof(flag))) {
2267 				msyslog(LOG_ERR, "set_reuseaddr: setsockopt(%s, SO_REUSEADDR, %s) failed: %m",
2268 					stoa(&ep->sin), flag ? "on" : "off");
2269 			}
2270 		}
2271 	}
2272 #endif /* ! SO_EXCLUSIVEADDRUSE */
2273 }
2274 
2275 /*
2276  * This is just a wrapper around an internal function so we can
2277  * make other changes as necessary later on
2278  */
2279 void
2280 enable_broadcast(
2281 	struct interface *	iface,
2282 	sockaddr_u *		baddr
2283 	)
2284 {
2285 #ifdef OPEN_BCAST_SOCKET
2286 	socket_broadcast_enable(iface, iface->fd, baddr);
2287 #endif
2288 }
2289 
2290 #ifdef OPEN_BCAST_SOCKET
2291 /*
2292  * Enable a broadcast address to a given socket
2293  * The socket is in the ep_list all we need to do is enable
2294  * broadcasting. It is not this function's job to select the socket
2295  */
2296 static isc_boolean_t
2297 socket_broadcast_enable(
2298 	struct interface *	iface,
2299 	SOCKET			fd,
2300 	sockaddr_u *		baddr
2301 	)
2302 {
2303 #ifdef SO_BROADCAST
2304 	int on = 1;
2305 
2306 	if (IS_IPV4(baddr)) {
2307 		/* if this interface can support broadcast, set SO_BROADCAST */
2308 		if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST,
2309 			       (char *)&on, sizeof(on)))
2310 			msyslog(LOG_ERR,
2311 				"setsockopt(SO_BROADCAST) enable failure on address %s: %m",
2312 				stoa(baddr));
2313 		else
2314 			DPRINTF(2, ("Broadcast enabled on socket %d for address %s\n",
2315 				    fd, stoa(baddr)));
2316 	}
2317 	iface->flags |= INT_BCASTXMIT;
2318 	return ISC_TRUE;
2319 #else
2320 	return ISC_FALSE;
2321 #endif /* SO_BROADCAST */
2322 }
2323 
2324 #ifdef  OS_MISSES_SPECIFIC_ROUTE_UPDATES
2325 /*
2326  * Remove a broadcast address from a given socket
2327  * The socket is in the ep_list all we need to do is disable
2328  * broadcasting. It is not this function's job to select the socket
2329  */
2330 static isc_boolean_t
2331 socket_broadcast_disable(
2332 	struct interface *	iface,
2333 	sockaddr_u *		baddr
2334 	)
2335 {
2336 #ifdef SO_BROADCAST
2337 	int off = 0;	/* This seems to be OK as an int */
2338 
2339 	if (IS_IPV4(baddr) && setsockopt(iface->fd, SOL_SOCKET,
2340 	    SO_BROADCAST, (char *)&off, sizeof(off)))
2341 		msyslog(LOG_ERR,
2342 			"setsockopt(SO_BROADCAST) disable failure on address %s: %m",
2343 			stoa(baddr));
2344 
2345 	iface->flags &= ~INT_BCASTXMIT;
2346 	return ISC_TRUE;
2347 #else
2348 	return ISC_FALSE;
2349 #endif /* SO_BROADCAST */
2350 }
2351 #endif /* OS_MISSES_SPECIFIC_ROUTE_UPDATES */
2352 
2353 #endif /* OPEN_BCAST_SOCKET */
2354 
2355 /*
2356  * return the broadcast client flag value
2357  */
2358 isc_boolean_t
2359 get_broadcastclient_flag(void)
2360 {
2361 	return (broadcast_client_enabled);
2362 }
2363 /*
2364  * Check to see if the address is a multicast address
2365  */
2366 static isc_boolean_t
2367 addr_ismulticast(
2368 	sockaddr_u *maddr
2369 	)
2370 {
2371 	isc_boolean_t result;
2372 
2373 #ifndef INCLUDE_IPV6_MULTICAST_SUPPORT
2374 	/*
2375 	 * If we don't have IPV6 support any IPV6 addr is not multicast
2376 	 */
2377 	if (IS_IPV6(maddr))
2378 		result = ISC_FALSE;
2379 	else
2380 #endif
2381 		result = IS_MCAST(maddr);
2382 
2383 	if (!result)
2384 		DPRINTF(4, ("address %s is not multicast\n",
2385 			    stoa(maddr)));
2386 
2387 	return result;
2388 }
2389 
2390 /*
2391  * Multicast servers need to set the appropriate Multicast interface
2392  * socket option in order for it to know which interface to use for
2393  * send the multicast packet.
2394  */
2395 void
2396 enable_multicast_if(
2397 	struct interface *	iface,
2398 	sockaddr_u *		maddr
2399 	)
2400 {
2401 #ifdef MCAST
2402 #ifdef IP_MULTICAST_LOOP
2403 	TYPEOF_IP_MULTICAST_LOOP off = 0;
2404 #endif
2405 #if defined(INCLUDE_IPV6_MULTICAST_SUPPORT) && defined(IPV6_MULTICAST_LOOP)
2406 	u_int off6 = 0;
2407 #endif
2408 
2409 	NTP_REQUIRE(AF(maddr) == AF(&iface->sin));
2410 
2411 	switch (AF(&iface->sin)) {
2412 
2413 	case AF_INET:
2414 #ifdef IP_MULTICAST_LOOP
2415 		/*
2416 		 * Don't send back to itself, but allow failure to set
2417 		 */
2418 		if (setsockopt(iface->fd, IPPROTO_IP,
2419 			       IP_MULTICAST_LOOP,
2420 			       SETSOCKOPT_ARG_CAST &off,
2421 			       sizeof(off))) {
2422 
2423 			msyslog(LOG_ERR,
2424 				"setsockopt IP_MULTICAST_LOOP failed: %m on socket %d, addr %s for multicast address %s",
2425 				iface->fd, stoa(&iface->sin),
2426 				stoa(maddr));
2427 		}
2428 #endif
2429 		break;
2430 
2431 	case AF_INET6:
2432 #ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2433 #ifdef IPV6_MULTICAST_LOOP
2434 		/*
2435 		 * Don't send back to itself, but allow failure to set
2436 		 */
2437 		if (setsockopt(iface->fd, IPPROTO_IPV6,
2438 			       IPV6_MULTICAST_LOOP,
2439 			       (char *) &off6, sizeof(off6))) {
2440 
2441 			msyslog(LOG_ERR,
2442 				"setsockopt IPV6_MULTICAST_LOOP failed: %m on socket %d, addr %s for multicast address %s",
2443 				iface->fd, stoa(&iface->sin),
2444 				stoa(maddr));
2445 		}
2446 #endif
2447 		break;
2448 #else
2449 		return;
2450 #endif	/* INCLUDE_IPV6_MULTICAST_SUPPORT */
2451 	}
2452 	return;
2453 #endif
2454 }
2455 
2456 /*
2457  * Add a multicast address to a given socket
2458  * The socket is in the ep_list all we need to do is enable
2459  * multicasting. It is not this function's job to select the socket
2460  */
2461 #if defined(MCAST)
2462 static isc_boolean_t
2463 socket_multicast_enable(
2464 	endpt *		iface,
2465 	sockaddr_u *	maddr
2466 	)
2467 {
2468 	struct ip_mreq		mreq;
2469 #ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2470 	struct ipv6_mreq	mreq6;
2471 #endif
2472 	switch (AF(maddr)) {
2473 
2474 	case AF_INET:
2475 		ZERO(mreq);
2476 		mreq.imr_multiaddr = SOCK_ADDR4(maddr);
2477 		mreq.imr_interface.s_addr = htonl(INADDR_ANY);
2478 		if (setsockopt(iface->fd,
2479 			       IPPROTO_IP,
2480 			       IP_ADD_MEMBERSHIP,
2481 			       (char *)&mreq,
2482 			       sizeof(mreq))) {
2483 			DPRINTF(2, (
2484 				"setsockopt IP_ADD_MEMBERSHIP failed: %m on socket %d, addr %s for %x / %x (%s)",
2485 				iface->fd, stoa(&iface->sin),
2486 				mreq.imr_multiaddr.s_addr,
2487 				mreq.imr_interface.s_addr,
2488 				stoa(maddr)));
2489 			return ISC_FALSE;
2490 		}
2491 		DPRINTF(4, ("Added IPv4 multicast membership on socket %d, addr %s for %x / %x (%s)\n",
2492 			    iface->fd, stoa(&iface->sin),
2493 			    mreq.imr_multiaddr.s_addr,
2494 			    mreq.imr_interface.s_addr, stoa(maddr)));
2495 		break;
2496 
2497 	case AF_INET6:
2498 #ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2499 		/*
2500 		 * Enable reception of multicast packets.
2501 		 * If the address is link-local we can get the
2502 		 * interface index from the scope id. Don't do this
2503 		 * for other types of multicast addresses. For now let
2504 		 * the kernel figure it out.
2505 		 */
2506 		ZERO(mreq6);
2507 		mreq6.ipv6mr_multiaddr = SOCK_ADDR6(maddr);
2508 		mreq6.ipv6mr_interface = iface->ifindex;
2509 
2510 		if (setsockopt(iface->fd, IPPROTO_IPV6,
2511 			       IPV6_JOIN_GROUP, (char *)&mreq6,
2512 			       sizeof(mreq6))) {
2513 			DPRINTF(2, (
2514 				"setsockopt IPV6_JOIN_GROUP failed: %m on socket %d, addr %s for interface %u (%s)",
2515 				iface->fd, stoa(&iface->sin),
2516 				mreq6.ipv6mr_interface, stoa(maddr)));
2517 			return ISC_FALSE;
2518 		}
2519 		DPRINTF(4, ("Added IPv6 multicast group on socket %d, addr %s for interface %u (%s)\n",
2520 			    iface->fd, stoa(&iface->sin),
2521 			    mreq6.ipv6mr_interface, stoa(maddr)));
2522 #else
2523 		return ISC_FALSE;
2524 #endif	/* INCLUDE_IPV6_MULTICAST_SUPPORT */
2525 	}
2526 	iface->flags |= INT_MCASTOPEN;
2527 	iface->num_mcast++;
2528 
2529 	return ISC_TRUE;
2530 }
2531 #endif	/* MCAST */
2532 
2533 
2534 /*
2535  * Remove a multicast address from a given socket
2536  * The socket is in the ep_list all we need to do is disable
2537  * multicasting. It is not this function's job to select the socket
2538  */
2539 #ifdef MCAST
2540 static isc_boolean_t
2541 socket_multicast_disable(
2542 	struct interface *	iface,
2543 	sockaddr_u *		maddr
2544 	)
2545 {
2546 #ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2547 	struct ipv6_mreq mreq6;
2548 #endif
2549 	struct ip_mreq mreq;
2550 
2551 	ZERO(mreq);
2552 
2553 	if (find_addr_in_list(maddr) == NULL) {
2554 		DPRINTF(4, ("socket_multicast_disable(%s): not found\n",
2555 			    stoa(maddr)));
2556 		return ISC_TRUE;
2557 	}
2558 
2559 	switch (AF(maddr)) {
2560 
2561 	case AF_INET:
2562 		mreq.imr_multiaddr = SOCK_ADDR4(maddr);
2563 		mreq.imr_interface = SOCK_ADDR4(&iface->sin);
2564 		if (setsockopt(iface->fd, IPPROTO_IP,
2565 			       IP_DROP_MEMBERSHIP, (char *)&mreq,
2566 			       sizeof(mreq))) {
2567 
2568 			msyslog(LOG_ERR,
2569 				"setsockopt IP_DROP_MEMBERSHIP failed: %m on socket %d, addr %s for %x / %x (%s)",
2570 				iface->fd, stoa(&iface->sin),
2571 				SRCADR(maddr), SRCADR(&iface->sin),
2572 				stoa(maddr));
2573 			return ISC_FALSE;
2574 		}
2575 		break;
2576 	case AF_INET6:
2577 #ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2578 		/*
2579 		 * Disable reception of multicast packets
2580 		 * If the address is link-local we can get the
2581 		 * interface index from the scope id.  Don't do this
2582 		 * for other types of multicast addresses. For now let
2583 		 * the kernel figure it out.
2584 		 */
2585 		mreq6.ipv6mr_multiaddr = SOCK_ADDR6(maddr);
2586 		mreq6.ipv6mr_interface = iface->ifindex;
2587 
2588 		if (setsockopt(iface->fd, IPPROTO_IPV6,
2589 			       IPV6_LEAVE_GROUP, (char *)&mreq6,
2590 			       sizeof(mreq6))) {
2591 
2592 			msyslog(LOG_ERR,
2593 				"setsockopt IPV6_LEAVE_GROUP failure: %m on socket %d, addr %s for %d (%s)",
2594 				iface->fd, stoa(&iface->sin),
2595 				iface->ifindex, stoa(maddr));
2596 			return ISC_FALSE;
2597 		}
2598 		break;
2599 #else
2600 		return ISC_FALSE;
2601 #endif	/* INCLUDE_IPV6_MULTICAST_SUPPORT */
2602 	}
2603 
2604 	iface->num_mcast--;
2605 	if (!iface->num_mcast)
2606 		iface->flags &= ~INT_MCASTOPEN;
2607 
2608 	return ISC_TRUE;
2609 }
2610 #endif	/* MCAST */
2611 
2612 /*
2613  * io_setbclient - open the broadcast client sockets
2614  */
2615 void
2616 io_setbclient(void)
2617 {
2618 #ifdef OPEN_BCAST_SOCKET
2619 	struct interface *	interf;
2620 	int			nif;
2621 
2622 	nif = 0;
2623 	set_reuseaddr(1);
2624 
2625 	for (interf = ep_list;
2626 	     interf != NULL;
2627 	     interf = interf->elink) {
2628 
2629 		if (interf->flags & (INT_WILDCARD | INT_LOOPBACK))
2630 			continue;
2631 
2632 		/* use only allowed addresses */
2633 		if (interf->ignore_packets)
2634 			continue;
2635 
2636 		/* Need a broadcast-capable interface */
2637 		if (!(interf->flags & INT_BROADCAST))
2638 			continue;
2639 
2640 		/* Only IPv4 addresses are valid for broadcast */
2641 		NTP_REQUIRE(IS_IPV4(&interf->sin));
2642 
2643 		/* Do we already have the broadcast address open? */
2644 		if (interf->flags & INT_BCASTOPEN) {
2645 			/*
2646 			 * account for already open interfaces to avoid
2647 			 * misleading warning below
2648 			 */
2649 			nif++;
2650 			continue;
2651 		}
2652 
2653 		/*
2654 		 * Try to open the broadcast address
2655 		 */
2656 		interf->family = AF_INET;
2657 		interf->bfd = open_socket(&interf->bcast, 1, 0, interf);
2658 
2659 		/*
2660 		 * If we succeeded then we use it otherwise enable
2661 		 * broadcast on the interface address
2662 		 */
2663 		if (interf->bfd != INVALID_SOCKET) {
2664 			nif++;
2665 			interf->flags |= INT_BCASTOPEN;
2666 			msyslog(LOG_INFO,
2667 				"Listen for broadcasts to %s on interface #%d %s",
2668 				stoa(&interf->bcast), interf->ifnum, interf->name);
2669 		} else {
2670 			/* silently ignore EADDRINUSE as we probably opened
2671 			   the socket already for an address in the same network */
2672 			if (errno != EADDRINUSE)
2673 				msyslog(LOG_INFO,
2674 					"failed to listen for broadcasts to %s on interface #%d %s",
2675 					stoa(&interf->bcast), interf->ifnum, interf->name);
2676 		}
2677 	}
2678 	set_reuseaddr(0);
2679 	if (nif > 0) {
2680 		broadcast_client_enabled = ISC_TRUE;
2681 		DPRINTF(1, ("io_setbclient: listening to %d broadcast addresses\n", nif));
2682 	}
2683 	else if (!nif) {
2684 		broadcast_client_enabled = ISC_FALSE;
2685 		msyslog(LOG_ERR,
2686 			"Unable to listen for broadcasts, no broadcast interfaces available");
2687 	}
2688 #else
2689 	msyslog(LOG_ERR,
2690 		"io_setbclient: Broadcast Client disabled by build");
2691 #endif	/* OPEN_BCAST_SOCKET */
2692 }
2693 
2694 /*
2695  * io_unsetbclient - close the broadcast client sockets
2696  */
2697 void
2698 io_unsetbclient(void)
2699 {
2700 	endpt *ep;
2701 
2702 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2703 		if (INT_WILDCARD & ep->flags)
2704 			continue;
2705 		if (!(INT_BCASTOPEN & ep->flags))
2706 			continue;
2707 
2708 		if (ep->bfd != INVALID_SOCKET) {
2709 			/* destroy broadcast listening socket */
2710 			msyslog(LOG_INFO,
2711 				"stop listening for broadcasts to %s on interface #%d %s",
2712 				stoa(&ep->bcast), ep->ifnum, ep->name);
2713 			close_and_delete_fd_from_list(ep->bfd);
2714 			ep->bfd = INVALID_SOCKET;
2715 			ep->flags &= ~INT_BCASTOPEN;
2716 		}
2717 	}
2718 	broadcast_client_enabled = ISC_FALSE;
2719 }
2720 
2721 /*
2722  * io_multicast_add() - add multicast group address
2723  */
2724 void
2725 io_multicast_add(
2726 	sockaddr_u *addr
2727 	)
2728 {
2729 #ifdef MCAST
2730 	endpt *	ep;
2731 	endpt *	one_ep;
2732 
2733 	/*
2734 	 * Check to see if this is a multicast address
2735 	 */
2736 	if (!addr_ismulticast(addr))
2737 		return;
2738 
2739 	/* If we already have it we can just return */
2740 	if (NULL != find_flagged_addr_in_list(addr, INT_MCASTOPEN)) {
2741 		msyslog(LOG_INFO,
2742 			"Duplicate request found for multicast address %s",
2743 			stoa(addr));
2744 		return;
2745 	}
2746 
2747 #ifndef MULTICAST_NONEWSOCKET
2748 	ep = new_interface(NULL);
2749 
2750 	/*
2751 	 * Open a new socket for the multicast address
2752 	 */
2753 	ep->sin = *addr;
2754 	SET_PORT(&ep->sin, NTP_PORT);
2755 	ep->family = AF(&ep->sin);
2756 	AF(&ep->mask) = ep->family;
2757 	SET_ONESMASK(&ep->mask);
2758 
2759 	set_reuseaddr(1);
2760 	ep->bfd = INVALID_SOCKET;
2761 	ep->fd = open_socket(&ep->sin, 0, 0, ep);
2762 	if (ep->fd != INVALID_SOCKET) {
2763 		ep->ignore_packets = ISC_FALSE;
2764 		ep->flags |= INT_MCASTIF;
2765 
2766 		strlcpy(ep->name, "multicast", sizeof(ep->name));
2767 		DPRINT_INTERFACE(2, (ep, "multicast add ", "\n"));
2768 		add_interface(ep);
2769 		log_listen_address(ep);
2770 	} else {
2771 		/* bind failed, re-use wildcard interface */
2772 		delete_interface(ep);
2773 
2774 		if (IS_IPV4(addr))
2775 			ep = wildipv4;
2776 		else if (IS_IPV6(addr))
2777 			ep = wildipv6;
2778 		else
2779 			ep = NULL;
2780 
2781 		if (ep != NULL) {
2782 			/* HACK ! -- stuff in an address */
2783 			/* because we don't bind addr? DH */
2784 			ep->bcast = *addr;
2785 			msyslog(LOG_ERR,
2786 				"multicast address %s using wildcard interface #%d %s",
2787 				stoa(addr), ep->ifnum, ep->name);
2788 		} else {
2789 			msyslog(LOG_ERR,
2790 				"No multicast socket available to use for address %s",
2791 				stoa(addr));
2792 			return;
2793 		}
2794 	}
2795 	{	/* in place of the { following for in #else clause */
2796 		one_ep = ep;
2797 #else	/* MULTICAST_NONEWSOCKET follows */
2798 	/*
2799 	 * For the case where we can't use a separate socket (Windows)
2800 	 * join each applicable endpoint socket to the group address.
2801 	 */
2802 	if (IS_IPV4(addr))
2803 		one_ep = wildipv4;
2804 	else
2805 		one_ep = wildipv6;
2806 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2807 		if (ep->ignore_packets || AF(&ep->sin) != AF(addr) ||
2808 		    !(INT_MULTICAST & ep->flags) ||
2809 		    (INT_LOOPBACK | INT_WILDCARD) & ep->flags)
2810 			continue;
2811 		one_ep = ep;
2812 #endif	/* MULTICAST_NONEWSOCKET */
2813 		if (socket_multicast_enable(ep, addr))
2814 			msyslog(LOG_INFO,
2815 				"Joined %s socket to multicast group %s",
2816 				stoa(&ep->sin),
2817 				stoa(addr));
2818 	}
2819 
2820 	add_addr_to_list(addr, one_ep);
2821 #else	/* !MCAST  follows*/
2822 	msyslog(LOG_ERR,
2823 		"Can not add multicast address %s: no multicast support",
2824 		stoa(addr));
2825 #endif
2826 	return;
2827 }
2828 
2829 
2830 /*
2831  * io_multicast_del() - delete multicast group address
2832  */
2833 void
2834 io_multicast_del(
2835 	sockaddr_u *	addr
2836 	)
2837 {
2838 #ifdef MCAST
2839 	endpt *iface;
2840 
2841 	/*
2842 	 * Check to see if this is a multicast address
2843 	 */
2844 	if (!addr_ismulticast(addr)) {
2845 		msyslog(LOG_ERR, "invalid multicast address %s",
2846 			stoa(addr));
2847 		return;
2848 	}
2849 
2850 	/*
2851 	 * Disable reception of multicast packets
2852 	 */
2853 	while ((iface = find_flagged_addr_in_list(addr, INT_MCASTOPEN))
2854 	       != NULL)
2855 		socket_multicast_disable(iface, addr);
2856 
2857 	delete_addr_from_list(addr);
2858 
2859 #else /* not MCAST */
2860 	msyslog(LOG_ERR,
2861 		"Can not delete multicast address %s: no multicast support",
2862 		stoa(addr));
2863 #endif /* not MCAST */
2864 }
2865 
2866 
2867 /*
2868  * open_socket - open a socket, returning the file descriptor
2869  */
2870 
2871 static SOCKET
2872 open_socket(
2873 	sockaddr_u *	addr,
2874 	int		bcast,
2875 	int		turn_off_reuse,
2876 	endpt *		interf
2877 	)
2878 {
2879 	SOCKET	fd;
2880 	int	errval;
2881 	/*
2882 	 * int is OK for REUSEADR per
2883 	 * http://www.kohala.com/start/mcast.api.txt
2884 	 */
2885 	int	on = 1;
2886 	int	off = 0;
2887 
2888 	if (IS_IPV6(addr) && !ipv6_works)
2889 		return INVALID_SOCKET;
2890 
2891 	/* create a datagram (UDP) socket */
2892 	fd = socket(AF(addr), SOCK_DGRAM, 0);
2893 	if (INVALID_SOCKET == fd) {
2894 		errval = socket_errno();
2895 		msyslog(LOG_ERR,
2896 			"socket(AF_INET%s, SOCK_DGRAM, 0) failed on address %s: %m",
2897 			IS_IPV6(addr) ? "6" : "", stoa(addr));
2898 
2899 		if (errval == EPROTONOSUPPORT ||
2900 		    errval == EAFNOSUPPORT ||
2901 		    errval == EPFNOSUPPORT)
2902 			return (INVALID_SOCKET);
2903 
2904 		errno = errval;
2905 		msyslog(LOG_ERR,
2906 			"unexpected socket() error %m code %d (not EPROTONOSUPPORT nor EAFNOSUPPORT nor EPFNOSUPPORT) - exiting",
2907 			errno);
2908 		exit(1);
2909 	}
2910 
2911 #ifdef SYS_WINNT
2912 	connection_reset_fix(fd, addr);
2913 #endif
2914 	/*
2915 	 * Fixup the file descriptor for some systems
2916 	 * See bug #530 for details of the issue.
2917 	 */
2918 	fd = move_fd(fd);
2919 
2920 	/*
2921 	 * set SO_REUSEADDR since we will be binding the same port
2922 	 * number on each interface according to turn_off_reuse.
2923 	 * This is undesirable on Windows versions starting with
2924 	 * Windows XP (numeric version 5.1).
2925 	 */
2926 #ifdef SYS_WINNT
2927 	if (isc_win32os_versioncheck(5, 1, 0, 0) < 0)  /* before 5.1 */
2928 #endif
2929 		if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
2930 			       (char *)((turn_off_reuse)
2931 					    ? &off
2932 					    : &on),
2933 			       sizeof(on))) {
2934 
2935 			msyslog(LOG_ERR,
2936 				"setsockopt SO_REUSEADDR %s fails for address %s: %m",
2937 				(turn_off_reuse)
2938 				    ? "off"
2939 				    : "on",
2940 				stoa(addr));
2941 			closesocket(fd);
2942 			return INVALID_SOCKET;
2943 		}
2944 #ifdef SO_EXCLUSIVEADDRUSE
2945 	/*
2946 	 * setting SO_EXCLUSIVEADDRUSE on the wildcard we open
2947 	 * first will cause more specific binds to fail.
2948 	 */
2949 	if (!(interf->flags & INT_WILDCARD))
2950 		set_excladdruse(fd);
2951 #endif
2952 
2953 	/*
2954 	 * IPv4 specific options go here
2955 	 */
2956 	if (IS_IPV4(addr)) {
2957 #if defined(IPPROTO_IP) && defined(IP_TOS)
2958 		if (setsockopt(fd, IPPROTO_IP, IP_TOS, (char*)&qos,
2959 			       sizeof(qos)))
2960 			msyslog(LOG_ERR,
2961 				"setsockopt IP_TOS (%02x) fails on address %s: %m",
2962 				qos, stoa(addr));
2963 #endif /* IPPROTO_IP && IP_TOS */
2964 		if (bcast)
2965 			socket_broadcast_enable(interf, fd, addr);
2966 	}
2967 
2968 	/*
2969 	 * IPv6 specific options go here
2970 	 */
2971 	if (IS_IPV6(addr)) {
2972 #if defined(IPPROTO_IPV6) && defined(IPV6_TCLASS)
2973 		if (setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS, (char*)&qos,
2974 			       sizeof(qos)))
2975 			msyslog(LOG_ERR,
2976 				"setsockopt IPV6_TCLASS (%02x) fails on address %s: %m",
2977 				qos, stoa(addr));
2978 #endif /* IPPROTO_IPV6 && IPV6_TCLASS */
2979 #ifdef IPV6_V6ONLY
2980 		if (isc_net_probe_ipv6only() == ISC_R_SUCCESS
2981 		    && setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY,
2982 		    (char*)&on, sizeof(on)))
2983 			msyslog(LOG_ERR,
2984 				"setsockopt IPV6_V6ONLY on fails on address %s: %m",
2985 				stoa(addr));
2986 #endif
2987 #ifdef IPV6_BINDV6ONLY
2988 		if (setsockopt(fd, IPPROTO_IPV6, IPV6_BINDV6ONLY,
2989 		    (char*)&on, sizeof(on)))
2990 			msyslog(LOG_ERR,
2991 				"setsockopt IPV6_BINDV6ONLY on fails on address %s: %m",
2992 				stoa(addr));
2993 #endif
2994 	}
2995 
2996 #ifdef OS_NEEDS_REUSEADDR_FOR_IFADDRBIND
2997 	/*
2998 	 * some OSes don't allow binding to more specific
2999 	 * addresses if a wildcard address already bound
3000 	 * to the port and SO_REUSEADDR is not set
3001 	 */
3002 	if (!is_wildcard_addr(addr))
3003 		set_wildcard_reuse(AF(addr), 1);
3004 #endif
3005 
3006 	/*
3007 	 * bind the local address.
3008 	 */
3009 	errval = bind(fd, &addr->sa, SOCKLEN(addr));
3010 
3011 #ifdef OS_NEEDS_REUSEADDR_FOR_IFADDRBIND
3012 	if (!is_wildcard_addr(addr))
3013 		set_wildcard_reuse(AF(addr), 0);
3014 #endif
3015 
3016 	if (errval < 0) {
3017 		/*
3018 		 * Don't log this under all conditions
3019 		 */
3020 		if (turn_off_reuse == 0
3021 #ifdef DEBUG
3022 		    || debug > 1
3023 #endif
3024 		    ) {
3025 			msyslog(LOG_ERR,
3026 				"bind(%d) AF_INET%s %s#%d%s flags 0x%x failed: %m",
3027 				fd, IS_IPV6(addr) ? "6" : "",
3028 				stoa(addr), SRCPORT(addr),
3029 				IS_MCAST(addr) ? " (multicast)" : "",
3030 				interf->flags);
3031 		}
3032 
3033 		closesocket(fd);
3034 
3035 		return INVALID_SOCKET;
3036 	}
3037 
3038 #ifdef HAVE_TIMESTAMP
3039 	{
3040 		if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMP,
3041 			       (char*)&on, sizeof(on)))
3042 			msyslog(LOG_DEBUG,
3043 				"setsockopt SO_TIMESTAMP on fails on address %s: %m",
3044 				stoa(addr));
3045 		else
3046 			DPRINTF(4, ("setsockopt SO_TIMESTAMP enabled on fd %d address %s\n",
3047 				    fd, stoa(addr)));
3048 	}
3049 #endif
3050 #ifdef HAVE_TIMESTAMPNS
3051 	{
3052 		if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPNS,
3053 			       (char*)&on, sizeof(on)))
3054 			msyslog(LOG_DEBUG,
3055 				"setsockopt SO_TIMESTAMPNS on fails on address %s: %m",
3056 				stoa(addr));
3057 		else
3058 			DPRINTF(4, ("setsockopt SO_TIMESTAMPNS enabled on fd %d address %s\n",
3059 				    fd, stoa(addr)));
3060 	}
3061 #endif
3062 #ifdef HAVE_BINTIME
3063 	{
3064 		if (setsockopt(fd, SOL_SOCKET, SO_BINTIME,
3065 			       (char*)&on, sizeof(on)))
3066 			msyslog(LOG_DEBUG,
3067 				"setsockopt SO_BINTIME on fails on address %s: %m",
3068 				stoa(addr));
3069 		else
3070 			DPRINTF(4, ("setsockopt SO_BINTIME enabled on fd %d address %s\n",
3071 				    fd, stoa(addr)));
3072 	}
3073 #endif
3074 
3075 	DPRINTF(4, ("bind(%d) AF_INET%s, addr %s%%%d#%d, flags 0x%x\n",
3076 		   fd, IS_IPV6(addr) ? "6" : "", stoa(addr),
3077 		   SCOPE(addr), SRCPORT(addr), interf->flags));
3078 
3079 	make_socket_nonblocking(fd);
3080 
3081 #ifdef HAVE_SIGNALED_IO
3082 	init_socket_sig(fd);
3083 #endif /* not HAVE_SIGNALED_IO */
3084 
3085 	add_fd_to_list(fd, FD_TYPE_SOCKET);
3086 
3087 #if !defined(SYS_WINNT) && !defined(VMS)
3088 	DPRINTF(4, ("flags for fd %d: 0x%x\n", fd,
3089 		    fcntl(fd, F_GETFL, 0)));
3090 #endif /* SYS_WINNT || VMS */
3091 
3092 #if defined (HAVE_IO_COMPLETION_PORT)
3093 /*
3094  * Add the socket to the completion port
3095  */
3096 	if (io_completion_port_add_socket(fd, interf)) {
3097 		msyslog(LOG_ERR, "unable to set up io completion port - EXITING");
3098 		exit(1);
3099 	}
3100 #endif
3101 	return fd;
3102 }
3103 
3104 
3105 #ifdef SYS_WINNT
3106 #define sendto(fd, buf, len, flags, dest, destsz)	\
3107 	io_completion_port_sendto(fd, buf, len, (sockaddr_u *)(dest))
3108 #endif
3109 
3110 /* XXX ELIMINATE sendpkt similar in ntpq.c, ntpdc.c, ntp_io.c, ntptrace.c */
3111 /*
3112  * sendpkt - send a packet to the specified destination. Maintain a
3113  * send error cache so that only the first consecutive error for a
3114  * destination is logged.
3115  */
3116 void
3117 sendpkt(
3118 	sockaddr_u *		dest,
3119 	struct interface *	ep,
3120 	int			ttl,
3121 	struct pkt *		pkt,
3122 	int			len
3123 	)
3124 {
3125 	endpt *	src;
3126 	int	ismcast;
3127 	int	cc;
3128 	int	rc;
3129 	u_char	cttl;
3130 
3131 	ismcast = IS_MCAST(dest);
3132 	if (!ismcast)
3133 		src = ep;
3134 	else
3135 		src = (IS_IPV4(dest))
3136 			  ? mc4_list
3137 			  : mc6_list;
3138 
3139 	if (NULL == src) {
3140 		/*
3141 		 * unbound peer - drop request and wait for better
3142 		 * network conditions
3143 		 */
3144 		DPRINTF(2, ("%ssendpkt(dst=%s, ttl=%d, len=%d): no interface - IGNORED\n",
3145 			    ismcast ? "\tMCAST\t***** " : "",
3146 			    stoa(dest), ttl, len));
3147 		return;
3148 	}
3149 
3150 	do {
3151 		DPRINTF(2, ("%ssendpkt(%d, dst=%s, src=%s, ttl=%d, len=%d)\n",
3152 			    ismcast ? "\tMCAST\t***** " : "", src->fd,
3153 			    stoa(dest), stoa(&src->sin), ttl, len));
3154 #ifdef MCAST
3155 		/*
3156 		 * for the moment we use the bcast option to set multicast ttl
3157 		 */
3158 		if (ismcast && ttl > 0 && ttl != src->last_ttl) {
3159 			/*
3160 			 * set the multicast ttl for outgoing packets
3161 			 */
3162 			switch (AF(&src->sin)) {
3163 
3164 			case AF_INET :
3165 				cttl = (u_char)ttl;
3166 				rc = setsockopt(src->fd, IPPROTO_IP,
3167 						IP_MULTICAST_TTL,
3168 						(void *)&cttl,
3169 						sizeof(cttl));
3170 				break;
3171 
3172 # ifdef INCLUDE_IPV6_SUPPORT
3173 			case AF_INET6 :
3174 				rc = setsockopt(src->fd, IPPROTO_IPV6,
3175 						 IPV6_MULTICAST_HOPS,
3176 						 (void *)&ttl,
3177 						 sizeof(ttl));
3178 				break;
3179 # endif	/* INCLUDE_IPV6_SUPPORT */
3180 
3181 			default:
3182 				rc = 0;
3183 			}
3184 
3185 			if (!rc)
3186 				src->last_ttl = ttl;
3187 			else
3188 				msyslog(LOG_ERR,
3189 					"setsockopt IP_MULTICAST_TTL/IPV6_MULTICAST_HOPS fails on address %s: %m",
3190 					stoa(&src->sin));
3191 		}
3192 #endif	/* MCAST */
3193 
3194 #ifdef SIM
3195 		cc = simulate_server(dest, src, pkt);
3196 #else
3197 		cc = sendto(src->fd, (char *)pkt, (u_int)len, 0,
3198 			    &dest->sa, SOCKLEN(dest));
3199 #endif
3200 		if (cc == -1) {
3201 			src->notsent++;
3202 			packets_notsent++;
3203 		} else	{
3204 			src->sent++;
3205 			packets_sent++;
3206 		}
3207 		if (ismcast)
3208 			src = src->mclink;
3209 	} while (ismcast && src != NULL);
3210 }
3211 
3212 
3213 #if !defined(HAVE_IO_COMPLETION_PORT)
3214 /*
3215  * fdbits - generate ascii representation of fd_set (FAU debug support)
3216  * HFDF format - highest fd first.
3217  */
3218 static char *
3219 fdbits(
3220 	int count,
3221 	fd_set *set
3222 	)
3223 {
3224 	static char buffer[256];
3225 	char * buf = buffer;
3226 
3227 	count = min(count,  255);
3228 
3229 	while (count >= 0) {
3230 		*buf++ = FD_ISSET(count, set) ? '#' : '-';
3231 		count--;
3232 	}
3233 	*buf = '\0';
3234 
3235 	return buffer;
3236 }
3237 
3238 
3239 #ifdef REFCLOCK
3240 /*
3241  * Routine to read the refclock packets for a specific interface
3242  * Return the number of bytes read. That way we know if we should
3243  * read it again or go on to the next one if no bytes returned
3244  */
3245 static inline int
3246 read_refclock_packet(
3247 	SOCKET			fd,
3248 	struct refclockio *	rp,
3249 	l_fp			ts
3250 	)
3251 {
3252 	int			i;
3253 	int			buflen;
3254 	int			saved_errno;
3255 	int			consumed;
3256 	struct recvbuf *	rb;
3257 
3258 	rb = get_free_recv_buffer();
3259 
3260 	if (NULL == rb) {
3261 		/*
3262 		 * No buffer space available - just drop the packet
3263 		 */
3264 		char buf[RX_BUFF_SIZE];
3265 
3266 		buflen = read(fd, buf, sizeof buf);
3267 		packets_dropped++;
3268 		return (buflen);
3269 	}
3270 
3271 	i = (rp->datalen == 0
3272 	     || rp->datalen > (int)sizeof(rb->recv_space))
3273 		? (int)sizeof(rb->recv_space)
3274 		: rp->datalen;
3275 	do {
3276 		buflen = read(fd, (char *)&rb->recv_space, (u_int)i);
3277 	} while (buflen < 0 && EINTR == errno);
3278 
3279 	if (buflen <= 0) {
3280 		saved_errno = errno;
3281 		freerecvbuf(rb);
3282 		errno = saved_errno;
3283 		return buflen;
3284 	}
3285 
3286 	/*
3287 	 * Got one. Mark how and when it got here,
3288 	 * put it on the full list and do bookkeeping.
3289 	 */
3290 	rb->recv_length = buflen;
3291 	rb->recv_peer = rp->srcclock;
3292 	rb->dstadr = 0;
3293 	rb->fd = fd;
3294 	rb->recv_time = ts;
3295 	rb->receiver = rp->clock_recv;
3296 
3297 	consumed = indicate_refclock_packet(rp, rb);
3298 	if (!consumed) {
3299 		rp->recvcount++;
3300 		packets_received++;
3301 	}
3302 
3303 	return buflen;
3304 }
3305 #endif	/* REFCLOCK */
3306 
3307 
3308 #ifdef HAVE_PACKET_TIMESTAMP
3309 /*
3310  * extract timestamps from control message buffer
3311  */
3312 static l_fp
3313 fetch_timestamp(
3314 	struct recvbuf *	rb,
3315 	struct msghdr *		msghdr,
3316 	l_fp			ts
3317 	)
3318 {
3319 	struct cmsghdr *	cmsghdr;
3320 #ifdef HAVE_BINTIME
3321 	struct bintime *	btp;
3322 #endif
3323 #ifdef HAVE_TIMESTAMPNS
3324 	struct timespec *	tsp;
3325 #endif
3326 #ifdef HAVE_TIMESTAMP
3327 	struct timeval *	tvp;
3328 #endif
3329 	unsigned long		ticks;
3330 	double			fuzz;
3331 	l_fp			lfpfuzz;
3332 	l_fp			nts;
3333 #ifdef DEBUG_TIMING
3334 	l_fp			dts;
3335 #endif
3336 
3337 	cmsghdr = CMSG_FIRSTHDR(msghdr);
3338 	while (cmsghdr != NULL) {
3339 		switch (cmsghdr->cmsg_type)
3340 		{
3341 #ifdef HAVE_BINTIME
3342 		case SCM_BINTIME:
3343 #endif  /* HAVE_BINTIME */
3344 #ifdef HAVE_TIMESTAMPNS
3345 		case SCM_TIMESTAMPNS:
3346 #endif	/* HAVE_TIMESTAMPNS */
3347 #ifdef HAVE_TIMESTAMP
3348 		case SCM_TIMESTAMP:
3349 #endif	/* HAVE_TIMESTAMP */
3350 #if defined(HAVE_BINTIME) || defined (HAVE_TIMESTAMPNS) || defined(HAVE_TIMESTAMP)
3351 			switch (cmsghdr->cmsg_type)
3352 			{
3353 #ifdef HAVE_BINTIME
3354 			case SCM_BINTIME:
3355 				btp = (struct bintime *)CMSG_DATA(cmsghdr);
3356 				/*
3357 				 * bintime documentation is at http://phk.freebsd.dk/pubs/timecounter.pdf
3358 				 */
3359 				nts.l_i = btp->sec + JAN_1970;
3360 				nts.l_uf = (u_int32)(btp->frac >> 32);
3361 				if (sys_tick > measured_tick &&
3362 				    sys_tick > 1e-9) {
3363 					ticks = (unsigned long)(nts.l_uf / (unsigned long)(sys_tick * FRAC));
3364 					nts.l_uf = (unsigned long)(ticks * (unsigned long)(sys_tick * FRAC));
3365 				}
3366                                 DPRINTF(4, ("fetch_timestamp: system bintime network time stamp: %ld.%09lu\n",
3367                                             btp->sec, (unsigned long)((nts.l_uf / FRAC) * 1e9)));
3368 				break;
3369 #endif  /* HAVE_BINTIME */
3370 #ifdef HAVE_TIMESTAMPNS
3371 			case SCM_TIMESTAMPNS:
3372 				tsp = (struct timespec *)CMSG_DATA(cmsghdr);
3373 				if (sys_tick > measured_tick &&
3374 				    sys_tick > 1e-9) {
3375 					ticks = (unsigned long)((tsp->tv_nsec * 1e-9) /
3376 						       sys_tick);
3377 					tsp->tv_nsec = (long)(ticks * 1e9 *
3378 							      sys_tick);
3379 				}
3380 				DPRINTF(4, ("fetch_timestamp: system nsec network time stamp: %ld.%09ld\n",
3381 					    tsp->tv_sec, tsp->tv_nsec));
3382 				nts = tspec_stamp_to_lfp(*tsp);
3383 				break;
3384 #endif	/* HAVE_TIMESTAMPNS */
3385 #ifdef HAVE_TIMESTAMP
3386 			case SCM_TIMESTAMP:
3387 				tvp = (struct timeval *)CMSG_DATA(cmsghdr);
3388 				if (sys_tick > measured_tick &&
3389 				    sys_tick > 1e-6) {
3390 					ticks = (unsigned long)((tvp->tv_usec * 1e-6) /
3391 						       sys_tick);
3392 					tvp->tv_usec = (long)(ticks * 1e6 *
3393 							      sys_tick);
3394 				}
3395 				DPRINTF(4, ("fetch_timestamp: system usec network time stamp: %jd.%06ld\n",
3396 					    (intmax_t)tvp->tv_sec, (long)tvp->tv_usec));
3397 				nts = tval_stamp_to_lfp(*tvp);
3398 				break;
3399 #endif  /* HAVE_TIMESTAMP */
3400 			}
3401 			fuzz = ntp_random() * 2. / FRAC * sys_fuzz;
3402 			DTOLFP(fuzz, &lfpfuzz);
3403 			L_ADD(&nts, &lfpfuzz);
3404 #ifdef DEBUG_TIMING
3405 			dts = ts;
3406 			L_SUB(&dts, &nts);
3407 			collect_timing(rb, "input processing delay", 1,
3408 				       &dts);
3409 			DPRINTF(4, ("fetch_timestamp: timestamp delta: %s (incl. fuzz)\n",
3410 				    lfptoa(&dts, 9)));
3411 #endif	/* DEBUG_TIMING */
3412 			ts = nts;  /* network time stamp */
3413 			break;
3414 #endif	/* HAVE_BINTIME || HAVE_TIMESTAMPNS || HAVE_TIMESTAMP */
3415 
3416 		default:
3417 			DPRINTF(4, ("fetch_timestamp: skipping control message 0x%x\n",
3418 				    cmsghdr->cmsg_type));
3419 		}
3420 		cmsghdr = CMSG_NXTHDR(msghdr, cmsghdr);
3421 	}
3422 	return ts;
3423 }
3424 #endif	/* HAVE_PACKET_TIMESTAMP */
3425 
3426 
3427 /*
3428  * Routine to read the network NTP packets for a specific interface
3429  * Return the number of bytes read. That way we know if we should
3430  * read it again or go on to the next one if no bytes returned
3431  */
3432 static inline int
3433 read_network_packet(
3434 	SOCKET			fd,
3435 	struct interface *	itf,
3436 	l_fp			ts
3437 	)
3438 {
3439 	GETSOCKNAME_SOCKLEN_TYPE fromlen;
3440 	int buflen;
3441 	register struct recvbuf *rb;
3442 #ifdef HAVE_PACKET_TIMESTAMP
3443 	struct msghdr msghdr;
3444 	struct iovec iovec;
3445 	char control[CMSG_BUFSIZE];
3446 #endif
3447 
3448 	/*
3449 	 * Get a buffer and read the frame.  If we
3450 	 * haven't got a buffer, or this is received
3451 	 * on a disallowed socket, just dump the
3452 	 * packet.
3453 	 */
3454 
3455 	rb = get_free_recv_buffer();
3456 	if (NULL == rb || itf->ignore_packets) {
3457 		char buf[RX_BUFF_SIZE];
3458 		sockaddr_u from;
3459 
3460 		if (rb != NULL)
3461 			freerecvbuf(rb);
3462 
3463 		fromlen = sizeof(from);
3464 		buflen = recvfrom(fd, buf, sizeof(buf), 0,
3465 				  &from.sa, &fromlen);
3466 		DPRINTF(4, ("%s on (%lu) fd=%d from %s\n",
3467 			(itf->ignore_packets)
3468 			    ? "ignore"
3469 			    : "drop",
3470 			free_recvbuffs(), fd, stoa(&from)));
3471 		if (itf->ignore_packets)
3472 			packets_ignored++;
3473 		else
3474 			packets_dropped++;
3475 		return (buflen);
3476 	}
3477 
3478 	fromlen = sizeof(rb->recv_srcadr);
3479 
3480 #ifndef HAVE_PACKET_TIMESTAMP
3481 	rb->recv_length = recvfrom(fd, (char *)&rb->recv_space,
3482 				   sizeof(rb->recv_space), 0,
3483 				   &rb->recv_srcadr.sa, &fromlen);
3484 #else
3485 	iovec.iov_base        = &rb->recv_space;
3486 	iovec.iov_len         = sizeof(rb->recv_space);
3487 	msghdr.msg_name       = &rb->recv_srcadr;
3488 	msghdr.msg_namelen    = fromlen;
3489 	msghdr.msg_iov        = &iovec;
3490 	msghdr.msg_iovlen     = 1;
3491 	msghdr.msg_control    = (void *)&control;
3492 	msghdr.msg_controllen = sizeof(control);
3493 	msghdr.msg_flags      = 0;
3494 	rb->recv_length       = recvmsg(fd, &msghdr, 0);
3495 #endif
3496 
3497 	buflen = rb->recv_length;
3498 
3499 	if (buflen == 0 || (buflen == -1 &&
3500 	    (EWOULDBLOCK == errno
3501 #ifdef EAGAIN
3502 	     || EAGAIN == errno
3503 #endif
3504 	     ))) {
3505 		freerecvbuf(rb);
3506 		return (buflen);
3507 	} else if (buflen < 0) {
3508 		msyslog(LOG_ERR, "recvfrom(%s) fd=%d: %m",
3509 			stoa(&rb->recv_srcadr), fd);
3510 		DPRINTF(5, ("read_network_packet: fd=%d dropped (bad recvfrom)\n",
3511 			    fd));
3512 		freerecvbuf(rb);
3513 		return (buflen);
3514 	}
3515 
3516 	DPRINTF(3, ("read_network_packet: fd=%d length %d from %s\n",
3517 		    fd, buflen, stoa(&rb->recv_srcadr)));
3518 
3519 	/*
3520 	** Bug 2672: Some OSes (MacOSX and Linux) don't block spoofed ::1
3521 	*/
3522 
3523 	if (AF_INET6 == itf->family) {
3524 		DPRINTF(2, ("Got an IPv6 packet, from <%s> (%d) to <%s> (%d)\n",
3525 			stoa(&rb->recv_srcadr),
3526 			IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&rb->recv_srcadr)),
3527 			stoa(&itf->sin),
3528 			!IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&itf->sin))
3529 			));
3530 
3531 		if (   IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&rb->recv_srcadr))
3532 		    && !IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&itf->sin))
3533 		   ) {
3534 			packets_dropped++;
3535 			DPRINTF(2, ("DROPPING that packet\n"));
3536 			freerecvbuf(rb);
3537 			return buflen;
3538 		}
3539 		DPRINTF(2, ("processing that packet\n"));
3540 	}
3541 
3542 	/*
3543 	 * Got one.  Mark how and when it got here,
3544 	 * put it on the full list and do bookkeeping.
3545 	 */
3546 	rb->dstadr = itf;
3547 	rb->fd = fd;
3548 #ifdef HAVE_PACKET_TIMESTAMP
3549 	/* pick up a network time stamp if possible */
3550 	ts = fetch_timestamp(rb, &msghdr, ts);
3551 #endif
3552 	rb->recv_time = ts;
3553 	rb->receiver = receive;
3554 
3555 	add_full_recv_buffer(rb);
3556 
3557 	itf->received++;
3558 	packets_received++;
3559 	return (buflen);
3560 }
3561 
3562 /*
3563  * attempt to handle io (select()/signaled IO)
3564  */
3565 void
3566 io_handler(void)
3567 {
3568 #  ifndef HAVE_SIGNALED_IO
3569 	fd_set rdfdes;
3570 	int nfound;
3571 
3572 	/*
3573 	 * Use select() on all on all input fd's for unlimited
3574 	 * time.  select() will terminate on SIGALARM or on the
3575 	 * reception of input.	Using select() means we can't do
3576 	 * robust signal handling and we get a potential race
3577 	 * between checking for alarms and doing the select().
3578 	 * Mostly harmless, I think.
3579 	 */
3580 	/*
3581 	 * On VMS, I suspect that select() can't be interrupted
3582 	 * by a "signal" either, so I take the easy way out and
3583 	 * have select() time out after one second.
3584 	 * System clock updates really aren't time-critical,
3585 	 * and - lacking a hardware reference clock - I have
3586 	 * yet to learn about anything else that is.
3587 	 */
3588 	rdfdes = activefds;
3589 #   if !defined(VMS) && !defined(SYS_VXWORKS)
3590 	nfound = select(maxactivefd + 1, &rdfdes, NULL,
3591 			NULL, NULL);
3592 #   else	/* VMS, VxWorks */
3593 	/* make select() wake up after one second */
3594 	{
3595 		struct timeval t1;
3596 
3597 		t1.tv_sec = 1;
3598 		t1.tv_usec = 0;
3599 		nfound = select(maxactivefd + 1,
3600 				&rdfdes, NULL, NULL,
3601 				&t1);
3602 	}
3603 #   endif	/* VMS, VxWorks */
3604 	if (nfound > 0) {
3605 		l_fp ts;
3606 
3607 		get_systime(&ts);
3608 
3609 		input_handler(&ts);
3610 	} else if (nfound == -1 && errno != EINTR) {
3611 		msyslog(LOG_ERR, "select() error: %m");
3612 	}
3613 #   ifdef DEBUG
3614 	else if (debug > 4) {
3615 		msyslog(LOG_DEBUG, "select(): nfound=%d, error: %m", nfound);
3616 	} else {
3617 		DPRINTF(3, ("select() returned %d: %m\n", nfound));
3618 	}
3619 #   endif /* DEBUG */
3620 #  else /* HAVE_SIGNALED_IO */
3621 	wait_for_signal();
3622 #  endif /* HAVE_SIGNALED_IO */
3623 }
3624 
3625 /*
3626  * input_handler - receive packets asynchronously
3627  */
3628 static void
3629 input_handler(
3630 	l_fp *	cts
3631 	)
3632 {
3633 	int		buflen;
3634 	int		n;
3635 	u_int		idx;
3636 	int		doing;
3637 	SOCKET		fd;
3638 	blocking_child *c;
3639 	struct timeval	tvzero;
3640 	l_fp		ts;	/* Timestamp at BOselect() gob */
3641 #ifdef DEBUG_TIMING
3642 	l_fp		ts_e;	/* Timestamp at EOselect() gob */
3643 #endif
3644 	fd_set		fds;
3645 	size_t		select_count;
3646 	endpt *		ep;
3647 #ifdef REFCLOCK
3648 	struct refclockio *rp;
3649 	int		saved_errno;
3650 	const char *	clk;
3651 #endif
3652 #ifdef HAS_ROUTING_SOCKET
3653 	struct asyncio_reader *	asyncio_reader;
3654 	struct asyncio_reader *	next_asyncio_reader;
3655 #endif
3656 
3657 	handler_calls++;
3658 	select_count = 0;
3659 
3660 	/*
3661 	 * If we have something to do, freeze a timestamp.
3662 	 * See below for the other cases (nothing left to do or error)
3663 	 */
3664 	ts = *cts;
3665 
3666 	/*
3667 	 * Do a poll to see who has data
3668 	 */
3669 
3670 	fds = activefds;
3671 	tvzero.tv_sec = tvzero.tv_usec = 0;
3672 
3673 	n = select(maxactivefd + 1, &fds, (fd_set *)0, (fd_set *)0,
3674 		   &tvzero);
3675 
3676 	/*
3677 	 * If there are no packets waiting just return
3678 	 */
3679 	if (n < 0) {
3680 		int err = errno;
3681 		int j, b, prior;
3682 		/*
3683 		 * extended FAU debugging output
3684 		 */
3685 		if (err != EINTR)
3686 			msyslog(LOG_ERR,
3687 				"select(%d, %s, 0L, 0L, &0.0) error: %m",
3688 				maxactivefd + 1,
3689 				fdbits(maxactivefd, &activefds));
3690 		if (err != EBADF)
3691 			goto ih_return;
3692 		for (j = 0, prior = 0; j <= maxactivefd; j++) {
3693 			if (FD_ISSET(j, &activefds)) {
3694 				if (-1 != read(j, &b, 0)) {
3695 					prior = j;
3696 					continue;
3697 				}
3698 				msyslog(LOG_ERR,
3699 					"Removing bad file descriptor %d from select set",
3700 					j);
3701 				FD_CLR(j, &activefds);
3702 				if (j == maxactivefd)
3703 					maxactivefd = prior;
3704 			}
3705 		}
3706 		goto ih_return;
3707 	}
3708 	else if (n == 0)
3709 		goto ih_return;
3710 
3711 	++handler_pkts;
3712 
3713 #ifdef REFCLOCK
3714 	/*
3715 	 * Check out the reference clocks first, if any
3716 	 */
3717 
3718 	if (refio != NULL) {
3719 		for (rp = refio; rp != NULL; rp = rp->next) {
3720 			fd = rp->fd;
3721 
3722 			if (!FD_ISSET(fd, &fds))
3723 				continue;
3724 			++select_count;
3725 			buflen = read_refclock_packet(fd, rp, ts);
3726 			/*
3727 			 * The first read must succeed after select()
3728 			 * indicates readability, or we've reached
3729 			 * a permanent EOF.  http://bugs.ntp.org/1732
3730 			 * reported ntpd munching CPU after a USB GPS
3731 			 * was unplugged because select was indicating
3732 			 * EOF but ntpd didn't remove the descriptor
3733 			 * from the activefds set.
3734 			 */
3735 			if (buflen < 0 && EAGAIN != errno) {
3736 				saved_errno = errno;
3737 				clk = refnumtoa(&rp->srcclock->srcadr);
3738 				errno = saved_errno;
3739 				msyslog(LOG_ERR, "%s read: %m", clk);
3740 				maintain_activefds(fd, TRUE);
3741 			} else if (0 == buflen) {
3742 				clk = refnumtoa(&rp->srcclock->srcadr);
3743 				msyslog(LOG_ERR, "%s read EOF", clk);
3744 				maintain_activefds(fd, TRUE);
3745 			} else {
3746 				/* drain any remaining refclock input */
3747 				do {
3748 					buflen = read_refclock_packet(fd, rp, ts);
3749 				} while (buflen > 0);
3750 			}
3751 		}
3752 	}
3753 #endif /* REFCLOCK */
3754 
3755 	/*
3756 	 * Loop through the interfaces looking for data to read.
3757 	 */
3758 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
3759 		for (doing = 0; doing < 2; doing++) {
3760 			if (!doing) {
3761 				fd = ep->fd;
3762 			} else {
3763 				if (!(ep->flags & INT_BCASTOPEN))
3764 					break;
3765 				fd = ep->bfd;
3766 			}
3767 			if (fd < 0)
3768 				continue;
3769 			if (FD_ISSET(fd, &fds))
3770 				do {
3771 					++select_count;
3772 					buflen = read_network_packet(
3773 							fd, ep, ts);
3774 				} while (buflen > 0);
3775 			/* Check more interfaces */
3776 		}
3777 	}
3778 
3779 #ifdef HAS_ROUTING_SOCKET
3780 	/*
3781 	 * scan list of asyncio readers - currently only used for routing sockets
3782 	 */
3783 	asyncio_reader = asyncio_reader_list;
3784 
3785 	while (asyncio_reader != NULL) {
3786 		/* callback may unlink and free asyncio_reader */
3787 		next_asyncio_reader = asyncio_reader->link;
3788 		if (FD_ISSET(asyncio_reader->fd, &fds)) {
3789 			++select_count;
3790 			(*asyncio_reader->receiver)(asyncio_reader);
3791 		}
3792 		asyncio_reader = next_asyncio_reader;
3793 	}
3794 #endif /* HAS_ROUTING_SOCKET */
3795 
3796 	/*
3797 	 * Check for a response from a blocking child
3798 	 */
3799 	for (idx = 0; idx < blocking_children_alloc; idx++) {
3800 		c = blocking_children[idx];
3801 		if (NULL == c || -1 == c->resp_read_pipe)
3802 			continue;
3803 		if (FD_ISSET(c->resp_read_pipe, &fds)) {
3804 			select_count++;
3805 			process_blocking_resp(c);
3806 		}
3807 	}
3808 
3809 	/*
3810 	 * Done everything from that select.
3811 	 * If nothing to do, just return.
3812 	 * If an error occurred, complain and return.
3813 	 */
3814 	if (select_count == 0) { /* We really had nothing to do */
3815 #ifdef DEBUG
3816 		if (debug)
3817 			msyslog(LOG_DEBUG, "input_handler: select() returned 0");
3818 #endif /* DEBUG */
3819 		goto ih_return;
3820 	}
3821 	/* We've done our work */
3822 #ifdef DEBUG_TIMING
3823 	get_systime(&ts_e);
3824 	/*
3825 	 * (ts_e - ts) is the amount of time we spent
3826 	 * processing this gob of file descriptors.  Log
3827 	 * it.
3828 	 */
3829 	L_SUB(&ts_e, &ts);
3830 	collect_timing(NULL, "input handler", 1, &ts_e);
3831 	if (debug > 3)
3832 		msyslog(LOG_DEBUG,
3833 			"input_handler: Processed a gob of fd's in %s msec",
3834 			lfptoms(&ts_e, 6));
3835 #endif /* DEBUG_TIMING */
3836 	/* We're done... */
3837     ih_return:
3838 	return;
3839 }
3840 #endif /* !HAVE_IO_COMPLETION_PORT */
3841 
3842 
3843 /*
3844  * find an interface suitable for the src address
3845  */
3846 endpt *
3847 select_peerinterface(
3848 	struct peer *	peer,
3849 	sockaddr_u *	srcadr,
3850 	endpt *		dstadr
3851 	)
3852 {
3853 	endpt *ep;
3854 #ifndef SIM
3855 	endpt *wild;
3856 
3857 	wild = ANY_INTERFACE_CHOOSE(srcadr);
3858 
3859 	/*
3860 	 * Initialize the peer structure and dance the interface jig.
3861 	 * Reference clocks step the loopback waltz, the others
3862 	 * squaredance around the interface list looking for a buddy. If
3863 	 * the dance peters out, there is always the wildcard interface.
3864 	 * This might happen in some systems and would preclude proper
3865 	 * operation with public key cryptography.
3866 	 */
3867 	if (ISREFCLOCKADR(srcadr)) {
3868 		ep = loopback_interface;
3869 	} else if (peer->cast_flags &
3870 		   (MDF_BCLNT | MDF_ACAST | MDF_MCAST | MDF_BCAST)) {
3871 		ep = findbcastinter(srcadr);
3872 		if (ep != NULL)
3873 			DPRINTF(4, ("Found *-cast interface %s for address %s\n",
3874 				stoa(&ep->sin), stoa(srcadr)));
3875 		else
3876 			DPRINTF(4, ("No *-cast local address found for address %s\n",
3877 				stoa(srcadr)));
3878 	} else {
3879 		ep = dstadr;
3880 		if (NULL == ep)
3881 			ep = wild;
3882 	}
3883 	/*
3884 	 * If it is a multicast address, findbcastinter() may not find
3885 	 * it.  For unicast, we get to find the interface when dstadr is
3886 	 * given to us as the wildcard (ANY_INTERFACE_CHOOSE).  Either
3887 	 * way, try a little harder.
3888 	 */
3889 	if (wild == ep)
3890 		ep = findinterface(srcadr);
3891 	/*
3892 	 * we do not bind to the wildcard interfaces for output
3893 	 * as our (network) source address would be undefined and
3894 	 * crypto will not work without knowing the own transmit address
3895 	 */
3896 	if (ep != NULL && INT_WILDCARD & ep->flags)
3897 		if (!accept_wildcard_if_for_winnt)
3898 			ep = NULL;
3899 #else	/* SIM follows */
3900 	ep = loopback_interface;
3901 #endif
3902 
3903 	return ep;
3904 }
3905 
3906 
3907 /*
3908  * findinterface - find local interface corresponding to address
3909  */
3910 endpt *
3911 findinterface(
3912 	sockaddr_u *addr
3913 	)
3914 {
3915 	endpt *iface;
3916 
3917 	iface = findlocalinterface(addr, INT_WILDCARD, 0);
3918 
3919 	if (NULL == iface) {
3920 		DPRINTF(4, ("Found no interface for address %s - returning wildcard\n",
3921 			    stoa(addr)));
3922 
3923 		iface = ANY_INTERFACE_CHOOSE(addr);
3924 	} else
3925 		DPRINTF(4, ("Found interface #%d %s for address %s\n",
3926 			    iface->ifnum, iface->name, stoa(addr)));
3927 
3928 	return iface;
3929 }
3930 
3931 /*
3932  * findlocalinterface - find local interface corresponding to addr,
3933  * which does not have any of flags set.  If bast is nonzero, addr is
3934  * a broadcast address.
3935  *
3936  * This code attempts to find the local sending address for an outgoing
3937  * address by connecting a new socket to destinationaddress:NTP_PORT
3938  * and reading the sockname of the resulting connect.
3939  * the complicated sequence simulates the routing table lookup
3940  * for to first hop without duplicating any of the routing logic into
3941  * ntpd. preferably we would have used an API call - but its not there -
3942  * so this is the best we can do here short of duplicating to entire routing
3943  * logic in ntpd which would be a silly and really unportable thing to do.
3944  *
3945  */
3946 static endpt *
3947 findlocalinterface(
3948 	sockaddr_u *	addr,
3949 	int		flags,
3950 	int		bcast
3951 	)
3952 {
3953 	GETSOCKNAME_SOCKLEN_TYPE	sockaddrlen;
3954 	endpt *				iface;
3955 	sockaddr_u			saddr;
3956 	SOCKET				s;
3957 	int				rtn;
3958 	int				on;
3959 
3960 	DPRINTF(4, ("Finding interface for addr %s in list of addresses\n",
3961 		    stoa(addr)));
3962 
3963 	s = socket(AF(addr), SOCK_DGRAM, 0);
3964 	if (INVALID_SOCKET == s)
3965 		return NULL;
3966 
3967 	/*
3968 	 * If we are looking for broadcast interface we need to set this
3969 	 * socket to allow broadcast
3970 	 */
3971 	if (bcast) {
3972 		on = 1;
3973 		if (SOCKET_ERROR == setsockopt(s, SOL_SOCKET,
3974 						SO_BROADCAST,
3975 						(char *)&on,
3976 						sizeof(on))) {
3977 			closesocket(s);
3978 			return NULL;
3979 		}
3980 	}
3981 
3982 	rtn = connect(s, &addr->sa, SOCKLEN(addr));
3983 	if (SOCKET_ERROR == rtn) {
3984 		closesocket(s);
3985 		return NULL;
3986 	}
3987 
3988 	sockaddrlen = sizeof(saddr);
3989 	rtn = getsockname(s, &saddr.sa, &sockaddrlen);
3990 	closesocket(s);
3991 	if (SOCKET_ERROR == rtn)
3992 		return NULL;
3993 
3994 	DPRINTF(4, ("findlocalinterface: kernel maps %s to %s\n",
3995 		    stoa(addr), stoa(&saddr)));
3996 
3997 	iface = getinterface(&saddr, flags);
3998 
3999 	/*
4000 	 * if we didn't find an exact match on saddr, find the closest
4001 	 * available local address.  This handles the case of the
4002 	 * address suggested by the kernel being excluded by nic rules
4003 	 * or the user's -I and -L options to ntpd.
4004 	 * See http://bugs.ntp.org/1184 and http://bugs.ntp.org/1683
4005 	 * for more background.
4006 	 */
4007 	if (NULL == iface || iface->ignore_packets)
4008 		iface = findclosestinterface(&saddr,
4009 					     flags | INT_LOOPBACK);
4010 
4011 	/* Don't use an interface which will ignore replies */
4012 	if (iface != NULL && iface->ignore_packets)
4013 		iface = NULL;
4014 
4015 	return iface;
4016 }
4017 
4018 
4019 /*
4020  * findclosestinterface
4021  *
4022  * If there are -I/--interface or -L/novirtualips command-line options,
4023  * or "nic" or "interface" rules in ntp.conf, findlocalinterface() may
4024  * find the kernel's preferred local address for a given peer address is
4025  * administratively unavailable to ntpd, and punt to this routine's more
4026  * expensive search.
4027  *
4028  * Find the numerically closest local address to the one connect()
4029  * suggested.  This matches an address on the same subnet first, as
4030  * needed by Bug 1184, and provides a consistent choice if there are
4031  * multiple feasible local addresses, regardless of the order ntpd
4032  * enumerated them.
4033  */
4034 endpt *
4035 findclosestinterface(
4036 	sockaddr_u *	addr,
4037 	int		flags
4038 	)
4039 {
4040 	endpt *		ep;
4041 	endpt *		winner;
4042 	sockaddr_u	addr_dist;
4043 	sockaddr_u	min_dist;
4044 
4045 	ZERO_SOCK(&min_dist);
4046 	winner = NULL;
4047 
4048 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
4049 		if (ep->ignore_packets ||
4050 		    AF(addr) != ep->family ||
4051 		    flags & ep->flags)
4052 			continue;
4053 
4054 		calc_addr_distance(&addr_dist, addr, &ep->sin);
4055 		if (NULL == winner ||
4056 		    -1 == cmp_addr_distance(&addr_dist, &min_dist)) {
4057 			min_dist = addr_dist;
4058 			winner = ep;
4059 		}
4060 	}
4061 	if (NULL == winner)
4062 		DPRINTF(4, ("findclosestinterface(%s) failed\n",
4063 			    stoa(addr)));
4064 	else
4065 		DPRINTF(4, ("findclosestinterface(%s) -> %s\n",
4066 			    stoa(addr), stoa(&winner->sin)));
4067 
4068 	return winner;
4069 }
4070 
4071 
4072 /*
4073  * calc_addr_distance - calculate the distance between two addresses,
4074  *			the absolute value of the difference between
4075  *			the addresses numerically, stored as an address.
4076  */
4077 static void
4078 calc_addr_distance(
4079 	sockaddr_u *		dist,
4080 	const sockaddr_u *	a1,
4081 	const sockaddr_u *	a2
4082 	)
4083 {
4084 	u_int32	a1val;
4085 	u_int32	a2val;
4086 	u_int32	v4dist;
4087 	int	found_greater;
4088 	int	a1_greater;
4089 	int	i;
4090 
4091 	NTP_REQUIRE(AF(a1) == AF(a2));
4092 
4093 	ZERO_SOCK(dist);
4094 	AF(dist) = AF(a1);
4095 
4096 	/* v4 can be done a bit simpler */
4097 	if (IS_IPV4(a1)) {
4098 		a1val = SRCADR(a1);
4099 		a2val = SRCADR(a2);
4100 		v4dist = (a1val > a2val)
4101 			     ? a1val - a2val
4102 			     : a2val - a1val;
4103 		SET_ADDR4(dist, v4dist);
4104 
4105 		return;
4106 	}
4107 
4108 	found_greater = FALSE;
4109 	a1_greater = FALSE;	/* suppress pot. uninit. warning */
4110 	for (i = 0; i < (int)sizeof(NSRCADR6(a1)); i++) {
4111 		if (!found_greater &&
4112 		    NSRCADR6(a1)[i] != NSRCADR6(a2)[i]) {
4113 			found_greater = TRUE;
4114 			a1_greater = (NSRCADR6(a1)[i] > NSRCADR6(a2)[i]);
4115 		}
4116 		if (!found_greater) {
4117 			NSRCADR6(dist)[i] = 0;
4118 		} else {
4119 			if (a1_greater)
4120 				NSRCADR6(dist)[i] = NSRCADR6(a1)[i] -
4121 						    NSRCADR6(a2)[i];
4122 			else
4123 				NSRCADR6(dist)[i] = NSRCADR6(a2)[i] -
4124 						    NSRCADR6(a1)[i];
4125 		}
4126 	}
4127 }
4128 
4129 
4130 /*
4131  * cmp_addr_distance - compare two address distances, returning -1, 0,
4132  *		       1 to indicate their relationship.
4133  */
4134 static int
4135 cmp_addr_distance(
4136 	const sockaddr_u *	d1,
4137 	const sockaddr_u *	d2
4138 	)
4139 {
4140 	int	i;
4141 
4142 	NTP_REQUIRE(AF(d1) == AF(d2));
4143 
4144 	if (IS_IPV4(d1)) {
4145 		if (SRCADR(d1) < SRCADR(d2))
4146 			return -1;
4147 		else if (SRCADR(d1) == SRCADR(d2))
4148 			return 0;
4149 		else
4150 			return 1;
4151 	}
4152 
4153 	for (i = 0; i < (int)sizeof(NSRCADR6(d1)); i++) {
4154 		if (NSRCADR6(d1)[i] < NSRCADR6(d2)[i])
4155 			return -1;
4156 		else if (NSRCADR6(d1)[i] > NSRCADR6(d2)[i])
4157 			return 1;
4158 	}
4159 
4160 	return 0;
4161 }
4162 
4163 
4164 
4165 /*
4166  * fetch an interface structure the matches the
4167  * address and has the given flags NOT set
4168  */
4169 endpt *
4170 getinterface(
4171 	sockaddr_u *	addr,
4172 	u_int32		flags
4173 	)
4174 {
4175 	endpt *iface;
4176 
4177 	iface = find_addr_in_list(addr);
4178 
4179 	if (iface != NULL && (iface->flags & flags))
4180 		iface = NULL;
4181 
4182 	return iface;
4183 }
4184 
4185 
4186 /*
4187  * findbcastinter - find broadcast interface corresponding to address
4188  */
4189 endpt *
4190 findbcastinter(
4191 	sockaddr_u *addr
4192 	)
4193 {
4194 	endpt *	iface;
4195 
4196 	iface = NULL;
4197 #if !defined(MPE) && (defined(SIOCGIFCONF) || defined(SYS_WINNT))
4198 	DPRINTF(4, ("Finding broadcast/multicast interface for addr %s in list of addresses\n",
4199 		    stoa(addr)));
4200 
4201 	iface = findlocalinterface(addr, INT_LOOPBACK | INT_WILDCARD,
4202 				   1);
4203 	if (iface != NULL) {
4204 		DPRINTF(4, ("Easily found bcast-/mcast- interface index #%d %s\n",
4205 			    iface->ifnum, iface->name));
4206 		return iface;
4207 	}
4208 
4209 	/*
4210 	 * plan B - try to find something reasonable in our lists in
4211 	 * case kernel lookup doesn't help
4212 	 */
4213 	for (iface = ep_list; iface != NULL; iface = iface->elink) {
4214 		if (iface->flags & INT_WILDCARD)
4215 			continue;
4216 
4217 		/* Don't bother with ignored interfaces */
4218 		if (iface->ignore_packets)
4219 			continue;
4220 
4221 		/*
4222 		 * First look if this is the correct family
4223 		 */
4224 		if(AF(&iface->sin) != AF(addr))
4225 			continue;
4226 
4227 		/* Skip the loopback addresses */
4228 		if (iface->flags & INT_LOOPBACK)
4229 			continue;
4230 
4231 		/*
4232 		 * If we are looking to match a multicast address and
4233 		 * this interface is one...
4234 		 */
4235 		if (addr_ismulticast(addr)
4236 		    && (iface->flags & INT_MULTICAST)) {
4237 #ifdef INCLUDE_IPV6_SUPPORT
4238 			/*
4239 			 * ...it is the winner unless we're looking for
4240 			 * an interface to use for link-local multicast
4241 			 * and its address is not link-local.
4242 			 */
4243 			if (IS_IPV6(addr)
4244 			    && IN6_IS_ADDR_MC_LINKLOCAL(PSOCK_ADDR6(addr))
4245 			    && !IN6_IS_ADDR_LINKLOCAL(PSOCK_ADDR6(&iface->sin)))
4246 				continue;
4247 #endif
4248 			break;
4249 		}
4250 
4251 		/*
4252 		 * We match only those interfaces marked as
4253 		 * broadcastable and either the explicit broadcast
4254 		 * address or the network portion of the IP address.
4255 		 * Sloppy.
4256 		 */
4257 		if (IS_IPV4(addr)) {
4258 			if (SOCK_EQ(&iface->bcast, addr))
4259 				break;
4260 
4261 			if ((NSRCADR(&iface->sin) & NSRCADR(&iface->mask))
4262 			    == (NSRCADR(addr)	  & NSRCADR(&iface->mask)))
4263 				break;
4264 		}
4265 #ifdef INCLUDE_IPV6_SUPPORT
4266 		else if (IS_IPV6(addr)) {
4267 			if (SOCK_EQ(&iface->bcast, addr))
4268 				break;
4269 
4270 			if (SOCK_EQ(netof(&iface->sin), netof(addr)))
4271 				break;
4272 		}
4273 #endif
4274 	}
4275 #endif /* SIOCGIFCONF */
4276 	if (NULL == iface) {
4277 		DPRINTF(4, ("No bcast interface found for %s\n",
4278 			    stoa(addr)));
4279 		iface = ANY_INTERFACE_CHOOSE(addr);
4280 	} else {
4281 		DPRINTF(4, ("Found bcast-/mcast- interface index #%d %s\n",
4282 			    iface->ifnum, iface->name));
4283 	}
4284 
4285 	return iface;
4286 }
4287 
4288 
4289 /*
4290  * io_clr_stats - clear I/O module statistics
4291  */
4292 void
4293 io_clr_stats(void)
4294 {
4295 	packets_dropped = 0;
4296 	packets_ignored = 0;
4297 	packets_received = 0;
4298 	packets_sent = 0;
4299 	packets_notsent = 0;
4300 
4301 	handler_calls = 0;
4302 	handler_pkts = 0;
4303 	io_timereset = current_time;
4304 }
4305 
4306 
4307 #ifdef REFCLOCK
4308 /*
4309  * io_addclock - add a reference clock to the list and arrange that we
4310  *				 get SIGIO interrupts from it.
4311  */
4312 int
4313 io_addclock(
4314 	struct refclockio *rio
4315 	)
4316 {
4317 	BLOCKIO();
4318 
4319 	/*
4320 	 * Stuff the I/O structure in the list and mark the descriptor
4321 	 * in use.  There is a harmless (I hope) race condition here.
4322 	 */
4323 	rio->active = TRUE;
4324 
4325 # ifdef HAVE_SIGNALED_IO
4326 	if (init_clock_sig(rio)) {
4327 		UNBLOCKIO();
4328 		return 0;
4329 	}
4330 # elif defined(HAVE_IO_COMPLETION_PORT)
4331 	if (io_completion_port_add_clock_io(rio)) {
4332 		UNBLOCKIO();
4333 		return 0;
4334 	}
4335 # endif
4336 
4337 	/*
4338 	 * enqueue
4339 	 */
4340 	LINK_SLIST(refio, rio, next);
4341 
4342 	/*
4343 	 * register fd
4344 	 */
4345 	add_fd_to_list(rio->fd, FD_TYPE_FILE);
4346 
4347 	UNBLOCKIO();
4348 	return 1;
4349 }
4350 
4351 
4352 /*
4353  * io_closeclock - close the clock in the I/O structure given
4354  */
4355 void
4356 io_closeclock(
4357 	struct refclockio *rio
4358 	)
4359 {
4360 	struct refclockio *unlinked;
4361 
4362 	BLOCKIO();
4363 
4364 	/*
4365 	 * Remove structure from the list
4366 	 */
4367 	rio->active = FALSE;
4368 	UNLINK_SLIST(unlinked, refio, rio, next, struct refclockio);
4369 	if (NULL != unlinked) {
4370 		purge_recv_buffers_for_fd(rio->fd);
4371 		/*
4372 		 * Close the descriptor.
4373 		 */
4374 		close_and_delete_fd_from_list(rio->fd);
4375 	}
4376 	rio->fd = -1;
4377 
4378 	UNBLOCKIO();
4379 }
4380 #endif	/* REFCLOCK */
4381 
4382 
4383 /*
4384  * On NT a SOCKET is an unsigned int so we cannot possibly keep it in
4385  * an array. So we use one of the ISC_LIST functions to hold the
4386  * socket value and use that when we want to enumerate it.
4387  *
4388  * This routine is called by the forked intres child process to close
4389  * all open sockets.  On Windows there's no need as intres runs in
4390  * the same process as a thread.
4391  */
4392 #ifndef SYS_WINNT
4393 void
4394 kill_asyncio(
4395 	int	startfd
4396 	)
4397 {
4398 	BLOCKIO();
4399 
4400 	/*
4401 	 * In the child process we do not maintain activefds and
4402 	 * maxactivefd.  Zeroing maxactivefd disables code which
4403 	 * maintains it in close_and_delete_fd_from_list().
4404 	 */
4405 	maxactivefd = 0;
4406 
4407 	while (fd_list != NULL)
4408 		close_and_delete_fd_from_list(fd_list->fd);
4409 
4410 	UNBLOCKIO();
4411 }
4412 #endif	/* !SYS_WINNT */
4413 
4414 
4415 /*
4416  * Add and delete functions for the list of open sockets
4417  */
4418 static void
4419 add_fd_to_list(
4420 	SOCKET fd,
4421 	enum desc_type type
4422 	)
4423 {
4424 	vsock_t *lsock = emalloc(sizeof(*lsock));
4425 
4426 	lsock->fd = fd;
4427 	lsock->type = type;
4428 
4429 	LINK_SLIST(fd_list, lsock, link);
4430 	maintain_activefds(fd, 0);
4431 }
4432 
4433 
4434 static void
4435 close_and_delete_fd_from_list(
4436 	SOCKET fd
4437 	)
4438 {
4439 	vsock_t *lsock;
4440 
4441 	UNLINK_EXPR_SLIST(lsock, fd_list, fd ==
4442 	    UNLINK_EXPR_SLIST_CURRENT()->fd, link, vsock_t);
4443 
4444 	if (NULL == lsock)
4445 		return;
4446 
4447 	switch (lsock->type) {
4448 
4449 	case FD_TYPE_SOCKET:
4450 		closesocket(lsock->fd);
4451 		break;
4452 
4453 	case FD_TYPE_FILE:
4454 		closeserial(lsock->fd);
4455 		break;
4456 
4457 	default:
4458 		msyslog(LOG_ERR,
4459 			"internal error - illegal descriptor type %d - EXITING",
4460 			(int)lsock->type);
4461 		exit(1);
4462 	}
4463 
4464 	free(lsock);
4465 	/*
4466 	 * remove from activefds
4467 	 */
4468 	maintain_activefds(fd, 1);
4469 }
4470 
4471 
4472 static void
4473 add_addr_to_list(
4474 	sockaddr_u *	addr,
4475 	endpt *		ep
4476 	)
4477 {
4478 	remaddr_t *laddr;
4479 
4480 #ifdef DEBUG
4481 	if (find_addr_in_list(addr) == NULL) {
4482 #endif
4483 		/* not there yet - add to list */
4484 		laddr = emalloc(sizeof(*laddr));
4485 		laddr->addr = *addr;
4486 		laddr->ep = ep;
4487 
4488 		LINK_SLIST(remoteaddr_list, laddr, link);
4489 
4490 		DPRINTF(4, ("Added addr %s to list of addresses\n",
4491 			    stoa(addr)));
4492 #ifdef DEBUG
4493 	} else
4494 		DPRINTF(4, ("WARNING: Attempt to add duplicate addr %s to address list\n",
4495 			    stoa(addr)));
4496 #endif
4497 }
4498 
4499 
4500 static void
4501 delete_addr_from_list(
4502 	sockaddr_u *addr
4503 	)
4504 {
4505 	remaddr_t *unlinked;
4506 
4507 	UNLINK_EXPR_SLIST(unlinked, remoteaddr_list, SOCK_EQ(addr,
4508 		&(UNLINK_EXPR_SLIST_CURRENT()->addr)), link, remaddr_t);
4509 
4510 	if (unlinked != NULL) {
4511 		DPRINTF(4, ("Deleted addr %s from list of addresses\n",
4512 			stoa(addr)));
4513 		free(unlinked);
4514 	}
4515 }
4516 
4517 
4518 static void
4519 delete_interface_from_list(
4520 	endpt *iface
4521 	)
4522 {
4523 	remaddr_t *unlinked;
4524 
4525 	for (;;) {
4526 		UNLINK_EXPR_SLIST(unlinked, remoteaddr_list, iface ==
4527 		    UNLINK_EXPR_SLIST_CURRENT()->ep, link,
4528 		    remaddr_t);
4529 
4530 		if (unlinked == NULL)
4531 			break;
4532 		DPRINTF(4, ("Deleted addr %s for interface #%d %s from list of addresses\n",
4533 			    stoa(&unlinked->addr), iface->ifnum,
4534 			    iface->name));
4535 		free(unlinked);
4536 	}
4537 }
4538 
4539 
4540 static struct interface *
4541 find_addr_in_list(
4542 	sockaddr_u *addr
4543 	)
4544 {
4545 	remaddr_t *entry;
4546 
4547 	DPRINTF(4, ("Searching for addr %s in list of addresses - ",
4548 		    stoa(addr)));
4549 
4550 	for (entry = remoteaddr_list;
4551 	     entry != NULL;
4552 	     entry = entry->link)
4553 		if (SOCK_EQ(&entry->addr, addr)) {
4554 			DPRINTF(4, ("FOUND\n"));
4555 			return entry->ep;
4556 		}
4557 
4558 	DPRINTF(4, ("NOT FOUND\n"));
4559 	return NULL;
4560 }
4561 
4562 
4563 /*
4564  * Find the given address with the all given flags set in the list
4565  */
4566 static endpt *
4567 find_flagged_addr_in_list(
4568 	sockaddr_u *	addr,
4569 	u_int32		flags
4570 	)
4571 {
4572 	remaddr_t *entry;
4573 
4574 	DPRINTF(4, ("Finding addr %s with flags %d in list: ",
4575 		    stoa(addr), flags));
4576 
4577 	for (entry = remoteaddr_list;
4578 	     entry != NULL;
4579 	     entry = entry->link)
4580 
4581 		if (SOCK_EQ(&entry->addr, addr)
4582 		    && (entry->ep->flags & flags) == flags) {
4583 
4584 			DPRINTF(4, ("FOUND\n"));
4585 			return entry->ep;
4586 		}
4587 
4588 	DPRINTF(4, ("NOT FOUND\n"));
4589 	return NULL;
4590 }
4591 
4592 
4593 const char *
4594 localaddrtoa(
4595 	endpt *la
4596 	)
4597 {
4598 	return (NULL == la)
4599 		   ? "<null>"
4600 		   : stoa(&la->sin);
4601 }
4602 
4603 
4604 #ifdef HAS_ROUTING_SOCKET
4605 # ifndef UPDATE_GRACE
4606 #  define UPDATE_GRACE	2	/* wait UPDATE_GRACE seconds before scanning */
4607 # endif
4608 
4609 static void
4610 process_routing_msgs(struct asyncio_reader *reader)
4611 {
4612 	char buffer[5120];
4613 	int cnt, msg_type;
4614 #ifdef HAVE_RTNETLINK
4615 	struct nlmsghdr *nh;
4616 #else
4617 	struct rt_msghdr rtm;
4618 	char *p;
4619 #endif
4620 
4621 	if (disable_dynamic_updates) {
4622 		/*
4623 		 * discard ourselves if we are not needed any more
4624 		 * usually happens when running unprivileged
4625 		 */
4626 		remove_asyncio_reader(reader);
4627 		delete_asyncio_reader(reader);
4628 		return;
4629 	}
4630 
4631 	cnt = read(reader->fd, buffer, sizeof(buffer));
4632 
4633 	if (cnt < 0) {
4634 		msyslog(LOG_ERR,
4635 			"i/o error on routing socket %m - disabling");
4636 		remove_asyncio_reader(reader);
4637 		delete_asyncio_reader(reader);
4638 		return;
4639 	}
4640 
4641 	/*
4642 	 * process routing message
4643 	 */
4644 #ifdef HAVE_RTNETLINK
4645 	for (nh = (struct nlmsghdr *)buffer;
4646 	     NLMSG_OK(nh, cnt);
4647 	     nh = NLMSG_NEXT(nh, cnt)) {
4648 		msg_type = nh->nlmsg_type;
4649 #else
4650 	for (p = buffer;
4651 	     (p + sizeof(struct rt_msghdr)) <= (buffer + cnt);
4652 	     p += rtm.rtm_msglen) {
4653 		memcpy(&rtm, p, sizeof(rtm));
4654 		if (rtm.rtm_version != RTM_VERSION) {
4655 			msyslog(LOG_ERR,
4656 				"version mismatch (got %d - expected %d) on routing socket - disabling",
4657 				rtm.rtm_version, RTM_VERSION);
4658 
4659 			remove_asyncio_reader(reader);
4660 			delete_asyncio_reader(reader);
4661 			return;
4662 		}
4663 		msg_type = rtm.rtm_type;
4664 #endif
4665 		switch (msg_type) {
4666 #ifdef RTM_NEWADDR
4667 		case RTM_NEWADDR:
4668 #endif
4669 #ifdef RTM_DELADDR
4670 		case RTM_DELADDR:
4671 #endif
4672 #ifdef RTM_ADD
4673 		case RTM_ADD:
4674 #endif
4675 #ifdef RTM_DELETE
4676 		case RTM_DELETE:
4677 #endif
4678 #ifdef RTM_REDIRECT
4679 		case RTM_REDIRECT:
4680 #endif
4681 #ifdef RTM_CHANGE
4682 		case RTM_CHANGE:
4683 #endif
4684 #ifdef RTM_LOSING
4685 		case RTM_LOSING:
4686 #endif
4687 #ifdef RTM_IFINFO
4688 		case RTM_IFINFO:
4689 #endif
4690 #ifdef RTM_IFANNOUNCE
4691 		case RTM_IFANNOUNCE:
4692 #endif
4693 #ifdef RTM_NEWLINK
4694 		case RTM_NEWLINK:
4695 #endif
4696 #ifdef RTM_DELLINK
4697 		case RTM_DELLINK:
4698 #endif
4699 #ifdef RTM_NEWROUTE
4700 		case RTM_NEWROUTE:
4701 #endif
4702 #ifdef RTM_DELROUTE
4703 		case RTM_DELROUTE:
4704 #endif
4705 			/*
4706 			 * we are keen on new and deleted addresses and
4707 			 * if an interface goes up and down or routing
4708 			 * changes
4709 			 */
4710 			DPRINTF(3, ("routing message op = %d: scheduling interface update\n",
4711 				    msg_type));
4712 			timer_interfacetimeout(current_time + UPDATE_GRACE);
4713 			break;
4714 #ifdef HAVE_RTNETLINK
4715 		case NLMSG_DONE:
4716 			/* end of multipart message */
4717 			return;
4718 #endif
4719 		default:
4720 			/*
4721 			 * the rest doesn't bother us.
4722 			 */
4723 			DPRINTF(4, ("routing message op = %d: ignored\n",
4724 				    msg_type));
4725 			break;
4726 		}
4727 	}
4728 }
4729 
4730 /*
4731  * set up routing notifications
4732  */
4733 static void
4734 init_async_notifications()
4735 {
4736 	struct asyncio_reader *reader;
4737 #ifdef HAVE_RTNETLINK
4738 	int fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
4739 	struct sockaddr_nl sa;
4740 #else
4741 	int fd = socket(PF_ROUTE, SOCK_RAW, 0);
4742 #endif
4743 	if (fd < 0) {
4744 		msyslog(LOG_ERR,
4745 			"unable to open routing socket (%m) - using polled interface update");
4746 		return;
4747 	}
4748 
4749 	fd = move_fd(fd);
4750 #ifdef HAVE_RTNETLINK
4751 	ZERO(sa);
4752 	sa.nl_family = PF_NETLINK;
4753 	sa.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR
4754 		       | RTMGRP_IPV6_IFADDR | RTMGRP_IPV4_ROUTE
4755 		       | RTMGRP_IPV4_MROUTE | RTMGRP_IPV6_ROUTE
4756 		       | RTMGRP_IPV6_MROUTE;
4757 	if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
4758 		msyslog(LOG_ERR,
4759 			"bind failed on routing socket (%m) - using polled interface update");
4760 		return;
4761 	}
4762 #endif
4763 	make_socket_nonblocking(fd);
4764 #if defined(HAVE_SIGNALED_IO)
4765 	init_socket_sig(fd);
4766 #endif /* HAVE_SIGNALED_IO */
4767 
4768 	reader = new_asyncio_reader();
4769 
4770 	reader->fd = fd;
4771 	reader->receiver = process_routing_msgs;
4772 
4773 	add_asyncio_reader(reader, FD_TYPE_SOCKET);
4774 	msyslog(LOG_INFO,
4775 		"Listening on routing socket on fd #%d for interface updates",
4776 		fd);
4777 }
4778 #else
4779 /* HAS_ROUTING_SOCKET not defined */
4780 static void
4781 init_async_notifications(void)
4782 {
4783 }
4784 #endif
4785 
4786