xref: /freebsd/contrib/ntp/ntpd/ntp_io.c (revision f7c32ed617858bcd22f8d1b03199099d50125721)
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 #include "safecast.h"
45 
46 /* Don't include ISC's version of IPv6 variables and structures */
47 #define ISC_IPV6_H 1
48 #include <isc/mem.h>
49 #include <isc/interfaceiter.h>
50 #include <isc/netaddr.h>
51 #include <isc/result.h>
52 #include <isc/sockaddr.h>
53 
54 #ifdef SIM
55 #include "ntpsim.h"
56 #endif
57 
58 #ifdef HAS_ROUTING_SOCKET
59 # include <net/route.h>
60 # ifdef HAVE_RTNETLINK
61 #  include <linux/rtnetlink.h>
62 # endif
63 #endif
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 static 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_anycast		(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	void	set_reuseaddr	(int);
283 static	isc_boolean_t	socket_broadcast_enable	 (struct interface *, SOCKET, sockaddr_u *);
284 
285 #if !defined(HAVE_IO_COMPLETION_PORT) && !defined(HAVE_SIGNALED_IO)
286 static	char *	fdbits		(int, const fd_set *);
287 #endif
288 #ifdef  OS_MISSES_SPECIFIC_ROUTE_UPDATES
289 static	isc_boolean_t	socket_broadcast_disable (struct interface *, sockaddr_u *);
290 #endif
291 
292 typedef struct remaddr remaddr_t;
293 
294 struct remaddr {
295 	remaddr_t *		link;
296 	sockaddr_u		addr;
297 	endpt *			ep;
298 };
299 
300 remaddr_t *	remoteaddr_list;
301 endpt *		ep_list;	/* complete endpt list */
302 endpt *		mc4_list;	/* IPv4 mcast-capable unicast endpts */
303 endpt *		mc6_list;	/* IPv6 mcast-capable unicast endpts */
304 
305 static endpt *	wildipv4;
306 static endpt *	wildipv6;
307 
308 #ifdef SYS_WINNT
309 int accept_wildcard_if_for_winnt;
310 #else
311 const int accept_wildcard_if_for_winnt = FALSE;
312 #endif
313 
314 static void	add_fd_to_list		(SOCKET, enum desc_type);
315 static endpt *	find_addr_in_list	(sockaddr_u *);
316 static endpt *	find_flagged_addr_in_list(sockaddr_u *, u_int32);
317 static void	delete_addr_from_list	(sockaddr_u *);
318 static void	delete_interface_from_list(endpt *);
319 static void	close_and_delete_fd_from_list(SOCKET);
320 static void	add_addr_to_list	(sockaddr_u *, endpt *);
321 static void	create_wildcards	(u_short);
322 static endpt *	findlocalinterface	(sockaddr_u *, int, int);
323 static endpt *	findclosestinterface	(sockaddr_u *, int);
324 #ifdef DEBUG
325 static const char *	action_text	(nic_rule_action);
326 #endif
327 static nic_rule_action	interface_action(char *, sockaddr_u *, u_int32);
328 static void		convert_isc_if	(isc_interface_t *,
329 					 endpt *, u_short);
330 static void		calc_addr_distance(sockaddr_u *,
331 					   const sockaddr_u *,
332 					   const sockaddr_u *);
333 static int		cmp_addr_distance(const sockaddr_u *,
334 					  const sockaddr_u *);
335 
336 /*
337  * Routines to read the ntp packets
338  */
339 #if !defined(HAVE_IO_COMPLETION_PORT)
340 static inline int	read_network_packet	(SOCKET, struct interface *, l_fp);
341 static void		ntpd_addremove_io_fd	(int, int, int);
342 static void 		input_handler_scan	(const l_fp*, const fd_set*);
343 static int/*BOOL*/	sanitize_fdset		(int errc);
344 #ifdef REFCLOCK
345 static inline int	read_refclock_packet	(SOCKET, struct refclockio *, l_fp);
346 #endif
347 #ifdef HAVE_SIGNALED_IO
348 static void 		input_handler		(l_fp*);
349 #endif
350 #endif
351 
352 
353 #ifndef HAVE_IO_COMPLETION_PORT
354 void
355 maintain_activefds(
356 	int fd,
357 	int closing
358 	)
359 {
360 	int i;
361 
362 	if (fd < 0 || fd >= FD_SETSIZE) {
363 		msyslog(LOG_ERR,
364 			"Too many sockets in use, FD_SETSIZE %d exceeded by fd %d",
365 			FD_SETSIZE, fd);
366 		exit(1);
367 	}
368 
369 	if (!closing) {
370 		FD_SET(fd, &activefds);
371 		maxactivefd = max(fd, maxactivefd);
372 	} else {
373 		FD_CLR(fd, &activefds);
374 		if (maxactivefd && fd == maxactivefd) {
375 			for (i = maxactivefd - 1; i >= 0; i--)
376 				if (FD_ISSET(i, &activefds)) {
377 					maxactivefd = i;
378 					break;
379 				}
380 			INSIST(fd != maxactivefd);
381 		}
382 	}
383 }
384 #endif	/* !HAVE_IO_COMPLETION_PORT */
385 
386 
387 #ifdef DEBUG_TIMING
388 /*
389  * collect timing information for various processing
390  * paths. currently we only pass them on to the file
391  * for later processing. this could also do histogram
392  * based analysis in other to reduce the load (and skew)
393  * dur to the file output
394  */
395 void
396 collect_timing(struct recvbuf *rb, const char *tag, int count, l_fp *dts)
397 {
398 	char buf[256];
399 
400 	snprintf(buf, sizeof(buf), "%s %d %s %s",
401 		 (rb != NULL)
402 		     ? ((rb->dstadr != NULL)
403 			    ? stoa(&rb->recv_srcadr)
404 			    : "-REFCLOCK-")
405 		     : "-",
406 		 count, lfptoa(dts, 9), tag);
407 	record_timing_stats(buf);
408 }
409 #endif
410 
411 /*
412  * About dynamic interfaces, sockets, reception and more...
413  *
414  * the code solves following tasks:
415  *
416  *   - keep a current list of active interfaces in order
417  *     to bind to to the interface address on NTP_PORT so that
418  *     all wild and specific bindings for NTP_PORT are taken by ntpd
419  *     to avoid other daemons messing with the time or sockets.
420  *   - all interfaces keep a list of peers that are referencing
421  *     the interface in order to quickly re-assign the peers to
422  *     new interface in case an interface is deleted (=> gone from system or
423  *     down)
424  *   - have a preconfigured socket ready with the right local address
425  *     for transmission and reception
426  *   - have an address list for all destination addresses used within ntpd
427  *     to find the "right" preconfigured socket.
428  *   - facilitate updating the internal interface list with respect to
429  *     the current kernel state
430  *
431  * special issues:
432  *
433  *   - mapping of multicast addresses to the interface affected is not always
434  *     one to one - especially on hosts with multiple interfaces
435  *     the code here currently allocates a separate interface entry for those
436  *     multicast addresses
437  *     iff it is able to bind to a *new* socket with the multicast address (flags |= MCASTIF)
438  *     in case of failure the multicast address is bound to an existing interface.
439  *   - on some systems it is perfectly legal to assign the same address to
440  *     multiple interfaces. Therefore this code does not keep a list of interfaces
441  *     but a list of interfaces that represent a unique address as determined by the kernel
442  *     by the procedure in findlocalinterface. Thus it is perfectly legal to see only
443  *     one representative of a group of real interfaces if they share the same address.
444  *
445  * Frank Kardel 20050910
446  */
447 
448 /*
449  * init_io - initialize I/O module.
450  */
451 void
452 init_io(void)
453 {
454 	/* Init buffer free list and stat counters */
455 	init_recvbuff(RECV_INIT);
456 	/* update interface every 5 minutes as default */
457 	interface_interval = 300;
458 
459 #ifdef WORK_PIPE
460 	addremove_io_fd = &ntpd_addremove_io_fd;
461 #endif
462 
463 #if defined(SYS_WINNT)
464 	init_io_completion_port();
465 #elif defined(HAVE_SIGNALED_IO)
466 	(void) set_signal(input_handler);
467 #endif
468 }
469 
470 
471 static void
472 ntpd_addremove_io_fd(
473 	int	fd,
474 	int	is_pipe,
475 	int	remove_it
476 	)
477 {
478 	UNUSED_ARG(is_pipe);
479 
480 #ifdef HAVE_SIGNALED_IO
481 	if (!remove_it)
482 		init_socket_sig(fd);
483 #endif /* not HAVE_SIGNALED_IO */
484 
485 	maintain_activefds(fd, remove_it);
486 }
487 
488 
489 /*
490  * io_open_sockets - call socket creation routine
491  */
492 void
493 io_open_sockets(void)
494 {
495 	static int already_opened;
496 
497 	if (already_opened || HAVE_OPT( SAVECONFIGQUIT ))
498 		return;
499 
500 	already_opened = 1;
501 
502 	/*
503 	 * Create the sockets
504 	 */
505 	BLOCKIO();
506 	create_sockets(NTP_PORT);
507 	UNBLOCKIO();
508 
509 	init_async_notifications();
510 
511 	DPRINTF(3, ("io_open_sockets: maxactivefd %d\n", maxactivefd));
512 }
513 
514 
515 #ifdef DEBUG
516 /*
517  * function to dump the contents of the interface structure
518  * for debugging use only.
519  * We face a dilemma here -- sockets are FDs under POSIX and
520  * actually HANDLES under Windows. So we use '%lld' as format
521  * and cast the value to 'long long'; this should not hurt
522  * with UNIX-like systems and does not truncate values on Win64.
523  */
524 void
525 interface_dump(const endpt *itf)
526 {
527 	printf("Dumping interface: %p\n", itf);
528 	printf("fd = %lld\n", (long long)itf->fd);
529 	printf("bfd = %lld\n", (long long)itf->bfd);
530 	printf("sin = %s,\n", stoa(&itf->sin));
531 	sockaddr_dump(&itf->sin);
532 	printf("bcast = %s,\n", stoa(&itf->bcast));
533 	sockaddr_dump(&itf->bcast);
534 	printf("mask = %s,\n", stoa(&itf->mask));
535 	sockaddr_dump(&itf->mask);
536 	printf("name = %s\n", itf->name);
537 	printf("flags = 0x%08x\n", itf->flags);
538 	printf("last_ttl = %d\n", itf->last_ttl);
539 	printf("addr_refid = %08x\n", itf->addr_refid);
540 	printf("num_mcast = %d\n", itf->num_mcast);
541 	printf("received = %ld\n", itf->received);
542 	printf("sent = %ld\n", itf->sent);
543 	printf("notsent = %ld\n", itf->notsent);
544 	printf("ifindex = %u\n", itf->ifindex);
545 	printf("peercnt = %u\n", itf->peercnt);
546 	printf("phase = %u\n", itf->phase);
547 }
548 
549 /*
550  * sockaddr_dump - hex dump the start of a sockaddr_u
551  */
552 static void
553 sockaddr_dump(const sockaddr_u *psau)
554 {
555 	/* Limit the size of the sockaddr_in6 hex dump */
556 	const int maxsize = min(32, sizeof(psau->sa6));
557 	const u_char *	cp;
558 	int		i;
559 
560 	/* XXX: Should we limit maxsize based on psau->saX.sin_family? */
561 	cp = (const void *)&psau->sa6;
562 
563 	for(i = 0; i < maxsize; i++) {
564 		printf("%02x", *cp++);
565 		if (!((i + 1) % 4))
566 			printf(" ");
567 	}
568 	printf("\n");
569 }
570 
571 /*
572  * print_interface - helper to output debug information
573  */
574 static void
575 print_interface(const endpt *iface, const char *pfx, const char *sfx)
576 {
577 	printf("%sinterface #%d: fd=%lld, bfd=%lld, name=%s, flags=0x%x, ifindex=%u, sin=%s",
578 	       pfx,
579 	       iface->ifnum,
580 	       (long long)iface->fd,
581 	       (long long)iface->bfd,
582 	       iface->name,
583 	       iface->flags,
584 	       iface->ifindex,
585 	       stoa(&iface->sin));
586 	if (AF_INET == iface->family) {
587 		if (iface->flags & INT_BROADCAST)
588 			printf(", bcast=%s", stoa(&iface->bcast));
589 		printf(", mask=%s", stoa(&iface->mask));
590 	}
591 	printf(", %s:%s",
592 	       (iface->ignore_packets)
593 		   ? "Disabled"
594 		   : "Enabled",
595 	       sfx);
596 	if (debug > 4)	/* in-depth debugging only */
597 		interface_dump(iface);
598 }
599 #endif
600 
601 #if !defined(HAVE_IO_COMPLETION_PORT) && defined(HAS_ROUTING_SOCKET)
602 /*
603  * create an asyncio_reader structure
604  */
605 static struct asyncio_reader *
606 new_asyncio_reader(void)
607 {
608 	struct asyncio_reader *reader;
609 
610 	reader = emalloc_zero(sizeof(*reader));
611 	reader->fd = INVALID_SOCKET;
612 
613 	return reader;
614 }
615 
616 /*
617  * delete a reader
618  */
619 static void
620 delete_asyncio_reader(
621 	struct asyncio_reader *reader
622 	)
623 {
624 	free(reader);
625 }
626 
627 /*
628  * add asynchio_reader
629  */
630 static void
631 add_asyncio_reader(
632 	struct asyncio_reader *	reader,
633 	enum desc_type		type)
634 {
635 	LINK_SLIST(asyncio_reader_list, reader, link);
636 	add_fd_to_list(reader->fd, type);
637 }
638 
639 /*
640  * remove asynchio_reader
641  */
642 static void
643 remove_asyncio_reader(
644 	struct asyncio_reader *reader
645 	)
646 {
647 	struct asyncio_reader *unlinked;
648 
649 	UNLINK_SLIST(unlinked, asyncio_reader_list, reader, link,
650 	    struct asyncio_reader);
651 
652 	if (reader->fd != INVALID_SOCKET)
653 		close_and_delete_fd_from_list(reader->fd);
654 
655 	reader->fd = INVALID_SOCKET;
656 }
657 #endif /* !defined(HAVE_IO_COMPLETION_PORT) && defined(HAS_ROUTING_SOCKET) */
658 
659 
660 /* compare two sockaddr prefixes */
661 static int
662 addr_eqprefix(
663 	const sockaddr_u *	a,
664 	const sockaddr_u *	b,
665 	int			prefixlen
666 	)
667 {
668 	isc_netaddr_t		isc_a;
669 	isc_netaddr_t		isc_b;
670 	isc_sockaddr_t		isc_sa;
671 
672 	ZERO(isc_sa);
673 	memcpy(&isc_sa.type, a, min(sizeof(isc_sa.type), sizeof(*a)));
674 	isc_netaddr_fromsockaddr(&isc_a, &isc_sa);
675 
676 	ZERO(isc_sa);
677 	memcpy(&isc_sa.type, b, min(sizeof(isc_sa.type), sizeof(*b)));
678 	isc_netaddr_fromsockaddr(&isc_b, &isc_sa);
679 
680 	return (int)isc_netaddr_eqprefix(&isc_a, &isc_b,
681 					 (u_int)prefixlen);
682 }
683 
684 
685 static int
686 addr_samesubnet(
687 	const sockaddr_u *	a,
688 	const sockaddr_u *	a_mask,
689 	const sockaddr_u *	b,
690 	const sockaddr_u *	b_mask
691 	)
692 {
693 	const u_int32 *	pa;
694 	const u_int32 *	pa_limit;
695 	const u_int32 *	pb;
696 	const u_int32 *	pm;
697 	size_t		loops;
698 
699 	REQUIRE(AF(a) == AF(a_mask));
700 	REQUIRE(AF(b) == AF(b_mask));
701 	/*
702 	 * With address and mask families verified to match, comparing
703 	 * the masks also validates the address's families match.
704 	 */
705 	if (!SOCK_EQ(a_mask, b_mask))
706 		return FALSE;
707 
708 	if (IS_IPV6(a)) {
709 		loops = sizeof(NSRCADR6(a)) / sizeof(*pa);
710 		pa = (const void *)&NSRCADR6(a);
711 		pb = (const void *)&NSRCADR6(b);
712 		pm = (const void *)&NSRCADR6(a_mask);
713 	} else {
714 		loops = sizeof(NSRCADR(a)) / sizeof(*pa);
715 		pa = (const void *)&NSRCADR(a);
716 		pb = (const void *)&NSRCADR(b);
717 		pm = (const void *)&NSRCADR(a_mask);
718 	}
719 	for (pa_limit = pa + loops; pa < pa_limit; pa++, pb++, pm++)
720 		if ((*pa & *pm) != (*pb & *pm))
721 			return FALSE;
722 
723 	return TRUE;
724 }
725 
726 
727 /*
728  * interface list enumerator - visitor pattern
729  */
730 void
731 interface_enumerate(
732 	interface_receiver_t	receiver,
733 	void *			data
734 	)
735 {
736 	interface_info_t ifi;
737 
738 	ifi.action = IFS_EXISTS;
739 	for (ifi.ep = ep_list; ifi.ep != NULL; ifi.ep = ifi.ep->elink)
740 		(*receiver)(data, &ifi);
741 }
742 
743 /*
744  * do standard initialization of interface structure
745  */
746 static void
747 init_interface(
748 	endpt *ep
749 	)
750 {
751 	ZERO(*ep);
752 	ep->fd = INVALID_SOCKET;
753 	ep->bfd = INVALID_SOCKET;
754 	ep->phase = sys_interphase;
755 }
756 
757 
758 /*
759  * create new interface structure initialize from
760  * template structure or via standard initialization
761  * function
762  */
763 static struct interface *
764 new_interface(
765 	struct interface *interface
766 	)
767 {
768 	struct interface *	iface;
769 
770 	iface = emalloc(sizeof(*iface));
771 
772 	if (NULL == interface)
773 		init_interface(iface);
774 	else				/* use the template */
775 		memcpy(iface, interface, sizeof(*iface));
776 
777 	/* count every new instance of an interface in the system */
778 	iface->ifnum = sys_ifnum++;
779 	iface->starttime = current_time;
780 
781 #   ifdef HAVE_IO_COMPLETION_PORT
782 	if (!io_completion_port_add_interface(iface)) {
783 		msyslog(LOG_EMERG, "cannot register interface with IO engine -- will exit now");
784 		exit(1);
785 	}
786 #   endif
787 	return iface;
788 }
789 
790 
791 /*
792  * return interface storage into free memory pool
793  */
794 static void
795 delete_interface(
796 	endpt *ep
797 	)
798 {
799 #    ifdef HAVE_IO_COMPLETION_PORT
800 	io_completion_port_remove_interface(ep);
801 #    endif
802 	free(ep);
803 }
804 
805 
806 /*
807  * link interface into list of known interfaces
808  */
809 static void
810 add_interface(
811 	endpt *	ep
812 	)
813 {
814 	endpt **	pmclisthead;
815 	endpt *		scan;
816 	endpt *		scan_next;
817 	endpt *		unlinked;
818 	sockaddr_u *	addr;
819 	int		ep_local;
820 	int		scan_local;
821 	int		same_subnet;
822 	int		ep_univ_iid;	/* iface ID from MAC address */
823 	int		scan_univ_iid;	/* see RFC 4291 */
824 	int		ep_privacy;	/* random local iface ID */
825 	int		scan_privacy;	/* see RFC 4941 */
826 	int		rc;
827 
828 	/* Calculate the refid */
829 	ep->addr_refid = addr2refid(&ep->sin);
830 	/* link at tail so ntpdc -c ifstats index increases each row */
831 	LINK_TAIL_SLIST(ep_list, ep, elink, endpt);
832 	ninterfaces++;
833 #ifdef MCAST
834 	/* the rest is for enabled multicast-capable addresses only */
835 	if (ep->ignore_packets || !(INT_MULTICAST & ep->flags) ||
836 	    INT_LOOPBACK & ep->flags)
837 		return;
838 # ifndef INCLUDE_IPV6_MULTICAST_SUPPORT
839 	if (AF_INET6 == ep->family)
840 		return;
841 # endif
842 	pmclisthead = (AF_INET == ep->family)
843 			 ? &mc4_list
844 			 : &mc6_list;
845 
846 	if (AF_INET6 == ep->family) {
847 		ep_local =
848 		    IN6_IS_ADDR_LINKLOCAL(PSOCK_ADDR6(&ep->sin)) ||
849 		    IN6_IS_ADDR_SITELOCAL(PSOCK_ADDR6(&ep->sin));
850 		ep_univ_iid = IS_IID_UNIV(&ep->sin);
851 		ep_privacy = !!(INT_PRIVACY & ep->flags);
852 	} else {
853 		ep_local = FALSE;
854 		ep_univ_iid = FALSE;
855 		ep_privacy = FALSE;
856 	}
857 	DPRINTF(4, ("add_interface mcast-capable %s%s%s%s\n",
858 		    stoa(&ep->sin),
859 		    (ep_local) ? " link/scope-local" : "",
860 		    (ep_univ_iid) ? " univ-IID" : "",
861 		    (ep_privacy) ? " privacy" : ""));
862 	/*
863 	 * If we have multiple local addresses on the same network
864 	 * interface, and some are link- or site-local, do not multicast
865 	 * out from the link-/site-local addresses by default, to avoid
866 	 * duplicate manycastclient associations between v6 peers using
867 	 * link-local and global addresses.  link-local can still be
868 	 * chosen using "nic ignore myv6globalprefix::/64".
869 	 * Similarly, if we have multiple global addresses from the same
870 	 * prefix on the same network interface, multicast from one,
871 	 * preferring EUI-64, then static, then least RFC 4941 privacy
872 	 * addresses.
873 	 */
874 	for (scan = *pmclisthead; scan != NULL; scan = scan_next) {
875 		scan_next = scan->mclink;
876 		if (ep->family != scan->family)
877 			continue;
878 		if (strcmp(ep->name, scan->name))
879 			continue;
880 		same_subnet = addr_samesubnet(&ep->sin, &ep->mask,
881 					      &scan->sin, &scan->mask);
882 		if (AF_INET6 == ep->family) {
883 			addr = &scan->sin;
884 			scan_local =
885 			    IN6_IS_ADDR_LINKLOCAL(PSOCK_ADDR6(addr)) ||
886 			    IN6_IS_ADDR_SITELOCAL(PSOCK_ADDR6(addr));
887 			scan_univ_iid = IS_IID_UNIV(addr);
888 			scan_privacy = !!(INT_PRIVACY & scan->flags);
889 		} else {
890 			scan_local = FALSE;
891 			scan_univ_iid = FALSE;
892 			scan_privacy = FALSE;
893 		}
894 		DPRINTF(4, ("add_interface mcast-capable scan %s%s%s%s\n",
895 			    stoa(&scan->sin),
896 			    (scan_local) ? " link/scope-local" : "",
897 			    (scan_univ_iid) ? " univ-IID" : "",
898 			    (scan_privacy) ? " privacy" : ""));
899 		if ((ep_local && !scan_local) || (same_subnet &&
900 		    ((ep_privacy && !scan_privacy) ||
901 		     (!ep_univ_iid && scan_univ_iid)))) {
902 			DPRINTF(4, ("did not add %s to %s of IPv6 multicast-capable list which already has %s\n",
903 				stoa(&ep->sin),
904 				(ep_local)
905 				    ? "tail"
906 				    : "head",
907 				stoa(&scan->sin)));
908 			return;
909 		}
910 		if ((scan_local && !ep_local) || (same_subnet &&
911 		    ((scan_privacy && !ep_privacy) ||
912 		     (!scan_univ_iid && ep_univ_iid)))) {
913 			UNLINK_SLIST(unlinked, *pmclisthead,
914 				     scan, mclink, endpt);
915 			DPRINTF(4, ("%s %s from IPv6 multicast-capable list to add %s\n",
916 				(unlinked != scan)
917 				    ? "Failed to remove"
918 				    : "removed",
919 				stoa(&scan->sin), stoa(&ep->sin)));
920 		}
921 	}
922 	/*
923 	 * Add link/site local at the tail of the multicast-
924 	 * capable unicast interfaces list, so that ntpd will
925 	 * send from global addresses before link-/site-local
926 	 * ones.
927 	 */
928 	if (ep_local)
929 		LINK_TAIL_SLIST(*pmclisthead, ep, mclink, endpt);
930 	else
931 		LINK_SLIST(*pmclisthead, ep, mclink);
932 	DPRINTF(4, ("added %s to %s of IPv%s multicast-capable unicast local address list\n",
933 		stoa(&ep->sin),
934 		(ep_local)
935 		    ? "tail"
936 		    : "head",
937 		(AF_INET == ep->family)
938 		    ? "4"
939 		    : "6"));
940 
941 	if (INVALID_SOCKET == ep->fd)
942 		return;
943 
944 	/*
945 	 * select the local address from which to send to multicast.
946 	 */
947 	switch (AF(&ep->sin)) {
948 
949 	case AF_INET :
950 		rc = setsockopt(ep->fd, IPPROTO_IP,
951 				IP_MULTICAST_IF,
952 				(void *)&NSRCADR(&ep->sin),
953 				sizeof(NSRCADR(&ep->sin)));
954 		if (rc)
955 			msyslog(LOG_ERR,
956 				"setsockopt IP_MULTICAST_IF %s fails: %m",
957 				stoa(&ep->sin));
958 		break;
959 
960 # ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
961 	case AF_INET6 :
962 		rc = setsockopt(ep->fd, IPPROTO_IPV6,
963 				 IPV6_MULTICAST_IF,
964 				 (void *)&ep->ifindex,
965 				 sizeof(ep->ifindex));
966 		/* do not complain if bound addr scope is ifindex */
967 		if (rc && ep->ifindex != SCOPE(&ep->sin))
968 			msyslog(LOG_ERR,
969 				"setsockopt IPV6_MULTICAST_IF %u for %s fails: %m",
970 				ep->ifindex, stoa(&ep->sin));
971 		break;
972 # endif
973 	}
974 #endif	/* MCAST */
975 }
976 
977 
978 /*
979  * remove interface from known interface list and clean up
980  * associated resources
981  */
982 static void
983 remove_interface(
984 	endpt *	ep
985 	)
986 {
987 	endpt *		unlinked;
988 	endpt **	pmclisthead;
989 	sockaddr_u	resmask;
990 
991 	UNLINK_SLIST(unlinked, ep_list, ep, elink, endpt);
992 	if (!ep->ignore_packets && INT_MULTICAST & ep->flags) {
993 		pmclisthead = (AF_INET == ep->family)
994 				 ? &mc4_list
995 				 : &mc6_list;
996 		UNLINK_SLIST(unlinked, *pmclisthead, ep, mclink, endpt);
997 		DPRINTF(4, ("%s %s IPv%s multicast-capable unicast local address list\n",
998 			stoa(&ep->sin),
999 			(unlinked != NULL)
1000 			    ? "removed from"
1001 			    : "not found on",
1002 			(AF_INET == ep->family)
1003 			    ? "4"
1004 			    : "6"));
1005 	}
1006 	delete_interface_from_list(ep);
1007 
1008 	if (ep->fd != INVALID_SOCKET) {
1009 		msyslog(LOG_INFO,
1010 			"Deleting interface #%d %s, %s#%d, interface stats: received=%ld, sent=%ld, dropped=%ld, active_time=%ld secs",
1011 			ep->ifnum,
1012 			ep->name,
1013 			stoa(&ep->sin),
1014 			SRCPORT(&ep->sin),
1015 			ep->received,
1016 			ep->sent,
1017 			ep->notsent,
1018 			current_time - ep->starttime);
1019 #	    ifdef HAVE_IO_COMPLETION_PORT
1020 		io_completion_port_remove_socket(ep->fd, ep);
1021 #	    endif
1022 		close_and_delete_fd_from_list(ep->fd);
1023 		ep->fd = INVALID_SOCKET;
1024 	}
1025 
1026 	if (ep->bfd != INVALID_SOCKET) {
1027 		msyslog(LOG_INFO,
1028 			"stop listening for broadcasts to %s on interface #%d %s",
1029 			stoa(&ep->bcast), ep->ifnum, ep->name);
1030 #	    ifdef HAVE_IO_COMPLETION_PORT
1031 		io_completion_port_remove_socket(ep->bfd, ep);
1032 #	    endif
1033 		close_and_delete_fd_from_list(ep->bfd);
1034 		ep->bfd = INVALID_SOCKET;
1035 	}
1036 #   ifdef HAVE_IO_COMPLETION_PORT
1037 	io_completion_port_remove_interface(ep);
1038 #   endif
1039 
1040 	ninterfaces--;
1041 	mon_clearinterface(ep);
1042 
1043 	/* remove restrict interface entry */
1044 	SET_HOSTMASK(&resmask, AF(&ep->sin));
1045 	hack_restrict(RESTRICT_REMOVEIF, &ep->sin, &resmask,
1046 		      -3, RESM_NTPONLY | RESM_INTERFACE, RES_IGNORE, 0);
1047 }
1048 
1049 
1050 static void
1051 log_listen_address(
1052 	endpt *	ep
1053 	)
1054 {
1055 	msyslog(LOG_INFO, "%s on %d %s %s",
1056 		(ep->ignore_packets)
1057 		    ? "Listen and drop"
1058 		    : "Listen normally",
1059 		ep->ifnum,
1060 		ep->name,
1061 		sptoa(&ep->sin));
1062 }
1063 
1064 
1065 static void
1066 create_wildcards(
1067 	u_short	port
1068 	)
1069 {
1070 	int			v4wild;
1071 #ifdef INCLUDE_IPV6_SUPPORT
1072 	int			v6wild;
1073 #endif
1074 	sockaddr_u		wildaddr;
1075 	nic_rule_action		action;
1076 	struct interface *	wildif;
1077 
1078 	/*
1079 	 * silence "potentially uninitialized" warnings from VC9
1080 	 * failing to follow the logic.  Ideally action could remain
1081 	 * uninitialized, and the memset be the first statement under
1082 	 * the first if (v4wild).
1083 	 */
1084 	action = ACTION_LISTEN;
1085 	ZERO(wildaddr);
1086 
1087 #ifdef INCLUDE_IPV6_SUPPORT
1088 	/*
1089 	 * create pseudo-interface with wildcard IPv6 address
1090 	 */
1091 	v6wild = ipv6_works;
1092 	if (v6wild) {
1093 		/* set wildaddr to the v6 wildcard address :: */
1094 		ZERO(wildaddr);
1095 		AF(&wildaddr) = AF_INET6;
1096 		SET_ADDR6N(&wildaddr, in6addr_any);
1097 		SET_PORT(&wildaddr, port);
1098 		SET_SCOPE(&wildaddr, 0);
1099 
1100 		/* check for interface/nic rules affecting the wildcard */
1101 		action = interface_action(NULL, &wildaddr, 0);
1102 		v6wild = (ACTION_IGNORE != action);
1103 	}
1104 	if (v6wild) {
1105 		wildif = new_interface(NULL);
1106 
1107 		strlcpy(wildif->name, "v6wildcard", sizeof(wildif->name));
1108 		memcpy(&wildif->sin, &wildaddr, sizeof(wildif->sin));
1109 		wildif->family = AF_INET6;
1110 		AF(&wildif->mask) = AF_INET6;
1111 		SET_ONESMASK(&wildif->mask);
1112 
1113 		wildif->flags = INT_UP | INT_WILDCARD;
1114 		wildif->ignore_packets = (ACTION_DROP == action);
1115 
1116 		wildif->fd = open_socket(&wildif->sin, 0, 1, wildif);
1117 
1118 		if (wildif->fd != INVALID_SOCKET) {
1119 			wildipv6 = wildif;
1120 			any6_interface = wildif;
1121 			add_addr_to_list(&wildif->sin, wildif);
1122 			add_interface(wildif);
1123 			log_listen_address(wildif);
1124 		} else {
1125 			msyslog(LOG_ERR,
1126 				"unable to bind to wildcard address %s - another process may be running - EXITING",
1127 				stoa(&wildif->sin));
1128 			exit(1);
1129 		}
1130 		DPRINT_INTERFACE(2, (wildif, "created ", "\n"));
1131 	}
1132 #endif
1133 
1134 	/*
1135 	 * create pseudo-interface with wildcard IPv4 address
1136 	 */
1137 	v4wild = ipv4_works;
1138 	if (v4wild) {
1139 		/* set wildaddr to the v4 wildcard address 0.0.0.0 */
1140 		AF(&wildaddr) = AF_INET;
1141 		SET_ADDR4N(&wildaddr, INADDR_ANY);
1142 		SET_PORT(&wildaddr, port);
1143 
1144 		/* check for interface/nic rules affecting the wildcard */
1145 		action = interface_action(NULL, &wildaddr, 0);
1146 		v4wild = (ACTION_IGNORE != action);
1147 	}
1148 	if (v4wild) {
1149 		wildif = new_interface(NULL);
1150 
1151 		strlcpy(wildif->name, "v4wildcard", sizeof(wildif->name));
1152 		memcpy(&wildif->sin, &wildaddr, sizeof(wildif->sin));
1153 		wildif->family = AF_INET;
1154 		AF(&wildif->mask) = AF_INET;
1155 		SET_ONESMASK(&wildif->mask);
1156 
1157 		wildif->flags = INT_BROADCAST | INT_UP | INT_WILDCARD;
1158 		wildif->ignore_packets = (ACTION_DROP == action);
1159 #if defined(MCAST)
1160 		/*
1161 		 * enable multicast reception on the broadcast socket
1162 		 */
1163 		AF(&wildif->bcast) = AF_INET;
1164 		SET_ADDR4N(&wildif->bcast, INADDR_ANY);
1165 		SET_PORT(&wildif->bcast, port);
1166 #endif /* MCAST */
1167 		wildif->fd = open_socket(&wildif->sin, 0, 1, wildif);
1168 
1169 		if (wildif->fd != INVALID_SOCKET) {
1170 			wildipv4 = wildif;
1171 			any_interface = wildif;
1172 
1173 			add_addr_to_list(&wildif->sin, wildif);
1174 			add_interface(wildif);
1175 			log_listen_address(wildif);
1176 		} else {
1177 			msyslog(LOG_ERR,
1178 				"unable to bind to wildcard address %s - another process may be running - EXITING",
1179 				stoa(&wildif->sin));
1180 			exit(1);
1181 		}
1182 		DPRINT_INTERFACE(2, (wildif, "created ", "\n"));
1183 	}
1184 }
1185 
1186 
1187 /*
1188  * add_nic_rule() -- insert a rule entry at the head of nic_rule_list.
1189  */
1190 void
1191 add_nic_rule(
1192 	nic_rule_match	match_type,
1193 	const char *	if_name,	/* interface name or numeric address */
1194 	int		prefixlen,
1195 	nic_rule_action	action
1196 	)
1197 {
1198 	nic_rule *	rule;
1199 	isc_boolean_t	is_ip;
1200 
1201 	rule = emalloc_zero(sizeof(*rule));
1202 	rule->match_type = match_type;
1203 	rule->prefixlen = prefixlen;
1204 	rule->action = action;
1205 
1206 	if (MATCH_IFNAME == match_type) {
1207 		REQUIRE(NULL != if_name);
1208 		rule->if_name = estrdup(if_name);
1209 	} else if (MATCH_IFADDR == match_type) {
1210 		REQUIRE(NULL != if_name);
1211 		/* set rule->addr */
1212 		is_ip = is_ip_address(if_name, AF_UNSPEC, &rule->addr);
1213 		REQUIRE(is_ip);
1214 	} else
1215 		REQUIRE(NULL == if_name);
1216 
1217 	LINK_SLIST(nic_rule_list, rule, next);
1218 }
1219 
1220 
1221 #ifdef DEBUG
1222 static const char *
1223 action_text(
1224 	nic_rule_action	action
1225 	)
1226 {
1227 	const char *t;
1228 
1229 	switch (action) {
1230 
1231 	default:
1232 		t = "ERROR";	/* quiet uninit warning */
1233 		DPRINTF(1, ("fatal: unknown nic_rule_action %d\n",
1234 			    action));
1235 		ENSURE(0);
1236 		break;
1237 
1238 	case ACTION_LISTEN:
1239 		t = "listen";
1240 		break;
1241 
1242 	case ACTION_IGNORE:
1243 		t = "ignore";
1244 		break;
1245 
1246 	case ACTION_DROP:
1247 		t = "drop";
1248 		break;
1249 	}
1250 
1251 	return t;
1252 }
1253 #endif	/* DEBUG */
1254 
1255 
1256 static nic_rule_action
1257 interface_action(
1258 	char *		if_name,
1259 	sockaddr_u *	if_addr,
1260 	u_int32		if_flags
1261 	)
1262 {
1263 	nic_rule *	rule;
1264 	int		isloopback;
1265 	int		iswildcard;
1266 
1267 	DPRINTF(4, ("interface_action: interface %s ",
1268 		    (if_name != NULL) ? if_name : "wildcard"));
1269 
1270 	iswildcard = is_wildcard_addr(if_addr);
1271 	isloopback = !!(INT_LOOPBACK & if_flags);
1272 
1273 	/*
1274 	 * Find any matching NIC rule from --interface / -I or ntp.conf
1275 	 * interface/nic rules.
1276 	 */
1277 	for (rule = nic_rule_list; rule != NULL; rule = rule->next) {
1278 
1279 		switch (rule->match_type) {
1280 
1281 		case MATCH_ALL:
1282 			/* loopback and wildcard excluded from "all" */
1283 			if (isloopback || iswildcard)
1284 				break;
1285 			DPRINTF(4, ("nic all %s\n",
1286 			    action_text(rule->action)));
1287 			return rule->action;
1288 
1289 		case MATCH_IPV4:
1290 			if (IS_IPV4(if_addr)) {
1291 				DPRINTF(4, ("nic ipv4 %s\n",
1292 				    action_text(rule->action)));
1293 				return rule->action;
1294 			}
1295 			break;
1296 
1297 		case MATCH_IPV6:
1298 			if (IS_IPV6(if_addr)) {
1299 				DPRINTF(4, ("nic ipv6 %s\n",
1300 				    action_text(rule->action)));
1301 				return rule->action;
1302 			}
1303 			break;
1304 
1305 		case MATCH_WILDCARD:
1306 			if (iswildcard) {
1307 				DPRINTF(4, ("nic wildcard %s\n",
1308 				    action_text(rule->action)));
1309 				return rule->action;
1310 			}
1311 			break;
1312 
1313 		case MATCH_IFADDR:
1314 			if (rule->prefixlen != -1) {
1315 				if (addr_eqprefix(if_addr, &rule->addr,
1316 						  rule->prefixlen)) {
1317 
1318 					DPRINTF(4, ("subnet address match - %s\n",
1319 					    action_text(rule->action)));
1320 					return rule->action;
1321 				}
1322 			} else
1323 				if (SOCK_EQ(if_addr, &rule->addr)) {
1324 
1325 					DPRINTF(4, ("address match - %s\n",
1326 					    action_text(rule->action)));
1327 					return rule->action;
1328 				}
1329 			break;
1330 
1331 		case MATCH_IFNAME:
1332 			if (if_name != NULL
1333 #if defined(HAVE_FNMATCH) && defined(FNM_CASEFOLD)
1334 			    && !fnmatch(rule->if_name, if_name, FNM_CASEFOLD)
1335 #else
1336 			    && !strcasecmp(if_name, rule->if_name)
1337 #endif
1338 			    ) {
1339 
1340 				DPRINTF(4, ("interface name match - %s\n",
1341 				    action_text(rule->action)));
1342 				return rule->action;
1343 			}
1344 			break;
1345 		}
1346 	}
1347 
1348 	/*
1349 	 * Unless explicitly disabled such as with "nic ignore ::1"
1350 	 * listen on loopback addresses.  Since ntpq and ntpdc query
1351 	 * "localhost" by default, which typically resolves to ::1 and
1352 	 * 127.0.0.1, it's useful to default to listening on both.
1353 	 */
1354 	if (isloopback) {
1355 		DPRINTF(4, ("default loopback listen\n"));
1356 		return ACTION_LISTEN;
1357 	}
1358 
1359 	/*
1360 	 * Treat wildcard addresses specially.  If there is no explicit
1361 	 * "nic ... wildcard" or "nic ... 0.0.0.0" or "nic ... ::" rule
1362 	 * default to drop.
1363 	 */
1364 	if (iswildcard) {
1365 		DPRINTF(4, ("default wildcard drop\n"));
1366 		return ACTION_DROP;
1367 	}
1368 
1369 	/*
1370 	 * Check for "virtual IP" (colon in the interface name) after
1371 	 * the rules so that "ntpd --interface eth0:1 -novirtualips"
1372 	 * does indeed listen on eth0:1's addresses.
1373 	 */
1374 	if (!listen_to_virtual_ips && if_name != NULL
1375 	    && (strchr(if_name, ':') != NULL)) {
1376 
1377 		DPRINTF(4, ("virtual ip - ignore\n"));
1378 		return ACTION_IGNORE;
1379 	}
1380 
1381 	/*
1382 	 * If there are no --interface/-I command-line options and no
1383 	 * interface/nic rules in ntp.conf, the default action is to
1384 	 * listen.  In the presence of rules from either, the default
1385 	 * is to ignore.  This implements ntpd's traditional listen-
1386 	 * every default with no interface listen configuration, and
1387 	 * ensures a single -I eth0 or "nic listen eth0" means do not
1388 	 * listen on any other addresses.
1389 	 */
1390 	if (NULL == nic_rule_list) {
1391 		DPRINTF(4, ("default listen\n"));
1392 		return ACTION_LISTEN;
1393 	}
1394 
1395 	DPRINTF(4, ("implicit ignore\n"));
1396 	return ACTION_IGNORE;
1397 }
1398 
1399 
1400 static void
1401 convert_isc_if(
1402 	isc_interface_t *isc_if,
1403 	endpt *itf,
1404 	u_short port
1405 	)
1406 {
1407 	const u_char v6loop[16] = {0, 0, 0, 0, 0, 0, 0, 0,
1408 				   0, 0, 0, 0, 0, 0, 0, 1};
1409 
1410 	strlcpy(itf->name, isc_if->name, sizeof(itf->name));
1411 	itf->ifindex = isc_if->ifindex;
1412 	itf->family = (u_short)isc_if->af;
1413 	AF(&itf->sin) = itf->family;
1414 	AF(&itf->mask) = itf->family;
1415 	AF(&itf->bcast) = itf->family;
1416 	SET_PORT(&itf->sin, port);
1417 	SET_PORT(&itf->mask, port);
1418 	SET_PORT(&itf->bcast, port);
1419 
1420 	if (IS_IPV4(&itf->sin)) {
1421 		NSRCADR(&itf->sin) = isc_if->address.type.in.s_addr;
1422 		NSRCADR(&itf->mask) = isc_if->netmask.type.in.s_addr;
1423 
1424 		if (isc_if->flags & INTERFACE_F_BROADCAST) {
1425 			itf->flags |= INT_BROADCAST;
1426 			NSRCADR(&itf->bcast) =
1427 			    isc_if->broadcast.type.in.s_addr;
1428 		}
1429 	}
1430 #ifdef INCLUDE_IPV6_SUPPORT
1431 	else if (IS_IPV6(&itf->sin)) {
1432 		SET_ADDR6N(&itf->sin, isc_if->address.type.in6);
1433 		SET_ADDR6N(&itf->mask, isc_if->netmask.type.in6);
1434 
1435 		SET_SCOPE(&itf->sin, isc_if->address.zone);
1436 	}
1437 #endif /* INCLUDE_IPV6_SUPPORT */
1438 
1439 
1440 	/* Process the rest of the flags */
1441 
1442 	itf->flags |=
1443 		  ((INTERFACE_F_UP & isc_if->flags)
1444 			? INT_UP : 0)
1445 		| ((INTERFACE_F_LOOPBACK & isc_if->flags)
1446 			? INT_LOOPBACK : 0)
1447 		| ((INTERFACE_F_POINTTOPOINT & isc_if->flags)
1448 			? INT_PPP : 0)
1449 		| ((INTERFACE_F_MULTICAST & isc_if->flags)
1450 			? INT_MULTICAST : 0)
1451 		| ((INTERFACE_F_PRIVACY & isc_if->flags)
1452 			? INT_PRIVACY : 0)
1453 		;
1454 
1455 	/*
1456 	 * Clear the loopback flag if the address is not localhost.
1457 	 * http://bugs.ntp.org/1683
1458 	 */
1459 	if (INT_LOOPBACK & itf->flags) {
1460 		if (AF_INET == itf->family) {
1461 			if (127 != (SRCADR(&itf->sin) >> 24))
1462 				itf->flags &= ~INT_LOOPBACK;
1463 		} else {
1464 			if (memcmp(v6loop, NSRCADR6(&itf->sin),
1465 				   sizeof(NSRCADR6(&itf->sin))))
1466 				itf->flags &= ~INT_LOOPBACK;
1467 		}
1468 	}
1469 }
1470 
1471 
1472 /*
1473  * refresh_interface
1474  *
1475  * some OSes have been observed to keep
1476  * cached routes even when more specific routes
1477  * become available.
1478  * this can be mitigated by re-binding
1479  * the socket.
1480  */
1481 static int
1482 refresh_interface(
1483 	struct interface * interface
1484 	)
1485 {
1486 #ifdef  OS_MISSES_SPECIFIC_ROUTE_UPDATES
1487 	if (interface->fd != INVALID_SOCKET) {
1488 		int bcast = (interface->flags & INT_BCASTXMIT) != 0;
1489 		/* as we forcibly close() the socket remove the
1490 		   broadcast permission indication */
1491 		if (bcast)
1492 			socket_broadcast_disable(interface, &interface->sin);
1493 
1494 		close_and_delete_fd_from_list(interface->fd);
1495 
1496 		/* create new socket picking up a new first hop binding
1497 		   at connect() time */
1498 		interface->fd = open_socket(&interface->sin,
1499 					    bcast, 0, interface);
1500 		 /*
1501 		  * reset TTL indication so TTL is is set again
1502 		  * next time around
1503 		  */
1504 		interface->last_ttl = 0;
1505 		return (interface->fd != INVALID_SOCKET);
1506 	} else
1507 		return 0;	/* invalid sockets are not refreshable */
1508 #else /* !OS_MISSES_SPECIFIC_ROUTE_UPDATES */
1509 	return (interface->fd != INVALID_SOCKET);
1510 #endif /* !OS_MISSES_SPECIFIC_ROUTE_UPDATES */
1511 }
1512 
1513 /*
1514  * interface_update - externally callable update function
1515  */
1516 void
1517 interface_update(
1518 	interface_receiver_t	receiver,
1519 	void *			data)
1520 {
1521 	int new_interface_found;
1522 
1523 	if (disable_dynamic_updates)
1524 		return;
1525 
1526 	BLOCKIO();
1527 	new_interface_found = update_interfaces(NTP_PORT, receiver, data);
1528 	UNBLOCKIO();
1529 
1530 	if (!new_interface_found)
1531 		return;
1532 
1533 #ifdef DEBUG
1534 	msyslog(LOG_DEBUG, "new interface(s) found: waking up resolver");
1535 #endif
1536 	interrupt_worker_sleep();
1537 }
1538 
1539 
1540 /*
1541  * sau_from_netaddr() - convert network address on-wire formats.
1542  * Convert from libisc's isc_netaddr_t to NTP's sockaddr_u
1543  */
1544 void
1545 sau_from_netaddr(
1546 	sockaddr_u *psau,
1547 	const isc_netaddr_t *pna
1548 	)
1549 {
1550 	ZERO_SOCK(psau);
1551 	AF(psau) = (u_short)pna->family;
1552 	switch (pna->family) {
1553 
1554 	case AF_INET:
1555 		memcpy(&psau->sa4.sin_addr, &pna->type.in,
1556 		       sizeof(psau->sa4.sin_addr));
1557 		break;
1558 
1559 	case AF_INET6:
1560 		memcpy(&psau->sa6.sin6_addr, &pna->type.in6,
1561 		       sizeof(psau->sa6.sin6_addr));
1562 		break;
1563 	}
1564 }
1565 
1566 
1567 static int
1568 is_wildcard_addr(
1569 	const sockaddr_u *psau
1570 	)
1571 {
1572 	if (IS_IPV4(psau) && !NSRCADR(psau))
1573 		return 1;
1574 
1575 #ifdef INCLUDE_IPV6_SUPPORT
1576 	if (IS_IPV6(psau) && S_ADDR6_EQ(psau, &in6addr_any))
1577 		return 1;
1578 #endif
1579 
1580 	return 0;
1581 }
1582 
1583 
1584 #ifdef OS_NEEDS_REUSEADDR_FOR_IFADDRBIND
1585 /*
1586  * enable/disable re-use of wildcard address socket
1587  */
1588 static void
1589 set_wildcard_reuse(
1590 	u_short	family,
1591 	int	on
1592 	)
1593 {
1594 	struct interface *any;
1595 	SOCKET fd = INVALID_SOCKET;
1596 
1597 	any = ANY_INTERFACE_BYFAM(family);
1598 	if (any != NULL)
1599 		fd = any->fd;
1600 
1601 	if (fd != INVALID_SOCKET) {
1602 		if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
1603 			       (void *)&on, sizeof(on)))
1604 			msyslog(LOG_ERR,
1605 				"set_wildcard_reuse: setsockopt(SO_REUSEADDR, %s) failed: %m",
1606 				on ? "on" : "off");
1607 
1608 		DPRINTF(4, ("set SO_REUSEADDR to %s on %s\n",
1609 			    on ? "on" : "off",
1610 			    stoa(&any->sin)));
1611 	}
1612 }
1613 #endif /* OS_NEEDS_REUSEADDR_FOR_IFADDRBIND */
1614 
1615 static isc_boolean_t
1616 check_flags(
1617 	sockaddr_u *psau,
1618 	const char *name,
1619 	u_int32 flags
1620 	)
1621 {
1622 #if defined(SIOCGIFAFLAG_IN)
1623 	struct ifreq ifr;
1624 	int fd;
1625 
1626 	if (psau->sa.sa_family != AF_INET)
1627 		return ISC_FALSE;
1628 	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
1629 		return ISC_FALSE;
1630 	ZERO(ifr);
1631 	memcpy(&ifr.ifr_addr, &psau->sa, sizeof(ifr.ifr_addr));
1632 	strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
1633 	if (ioctl(fd, SIOCGIFAFLAG_IN, &ifr) < 0) {
1634 		close(fd);
1635 		return ISC_FALSE;
1636 	}
1637 	close(fd);
1638 	if ((ifr.ifr_addrflags & flags) != 0)
1639 		return ISC_TRUE;
1640 #endif	/* SIOCGIFAFLAG_IN */
1641 	return ISC_FALSE;
1642 }
1643 
1644 static isc_boolean_t
1645 check_flags6(
1646 	sockaddr_u *psau,
1647 	const char *name,
1648 	u_int32 flags6
1649 	)
1650 {
1651 #if defined(INCLUDE_IPV6_SUPPORT) && defined(SIOCGIFAFLAG_IN6)
1652 	struct in6_ifreq ifr6;
1653 	int fd;
1654 
1655 	if (psau->sa.sa_family != AF_INET6)
1656 		return ISC_FALSE;
1657 	if ((fd = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
1658 		return ISC_FALSE;
1659 	ZERO(ifr6);
1660 	memcpy(&ifr6.ifr_addr, &psau->sa6, sizeof(ifr6.ifr_addr));
1661 	strlcpy(ifr6.ifr_name, name, sizeof(ifr6.ifr_name));
1662 	if (ioctl(fd, SIOCGIFAFLAG_IN6, &ifr6) < 0) {
1663 		close(fd);
1664 		return ISC_FALSE;
1665 	}
1666 	close(fd);
1667 	if ((ifr6.ifr_ifru.ifru_flags6 & flags6) != 0)
1668 		return ISC_TRUE;
1669 #endif	/* INCLUDE_IPV6_SUPPORT && SIOCGIFAFLAG_IN6 */
1670 	return ISC_FALSE;
1671 }
1672 
1673 static isc_boolean_t
1674 is_anycast(
1675 	sockaddr_u *psau,
1676 	const char *name
1677 	)
1678 {
1679 #ifdef IN6_IFF_ANYCAST
1680 	return check_flags6(psau, name, IN6_IFF_ANYCAST);
1681 #else
1682 	return ISC_FALSE;
1683 #endif
1684 }
1685 
1686 static isc_boolean_t
1687 is_valid(
1688 	sockaddr_u *psau,
1689 	const char *name
1690 	)
1691 {
1692 	u_int32 flags;
1693 
1694 	flags = 0;
1695 	switch (psau->sa.sa_family) {
1696 	case AF_INET:
1697 #ifdef IN_IFF_DETACHED
1698 		flags |= IN_IFF_DETACHED;
1699 #endif
1700 #ifdef IN_IFF_TENTATIVE
1701 		flags |= IN_IFF_TENTATIVE;
1702 #endif
1703 		return check_flags(psau, name, flags) ? ISC_FALSE : ISC_TRUE;
1704 	case AF_INET6:
1705 #ifdef IN6_IFF_DEPARTED
1706 		flags |= IN6_IFF_DEPARTED;
1707 #endif
1708 #ifdef IN6_IFF_DETACHED
1709 		flags |= IN6_IFF_DETACHED;
1710 #endif
1711 #ifdef IN6_IFF_TENTATIVE
1712 		flags |= IN6_IFF_TENTATIVE;
1713 #endif
1714 		return check_flags6(psau, name, flags) ? ISC_FALSE : ISC_TRUE;
1715 	default:
1716 		return ISC_FALSE;
1717 	}
1718 }
1719 
1720 /*
1721  * update_interface strategy
1722  *
1723  * toggle configuration phase
1724  *
1725  * Phase 1:
1726  * forall currently existing interfaces
1727  *   if address is known:
1728  *	drop socket - rebind again
1729  *
1730  *   if address is NOT known:
1731  *	attempt to create a new interface entry
1732  *
1733  * Phase 2:
1734  * forall currently known non MCAST and WILDCARD interfaces
1735  *   if interface does not match configuration phase (not seen in phase 1):
1736  *	remove interface from known interface list
1737  *	forall peers associated with this interface
1738  *         disconnect peer from this interface
1739  *
1740  * Phase 3:
1741  *   attempt to re-assign interfaces to peers
1742  *
1743  */
1744 
1745 static int
1746 update_interfaces(
1747 	u_short			port,
1748 	interface_receiver_t	receiver,
1749 	void *			data
1750 	)
1751 {
1752 	isc_mem_t *		mctx = (void *)-1;
1753 	interface_info_t	ifi;
1754 	isc_interfaceiter_t *	iter;
1755 	isc_result_t		result;
1756 	isc_interface_t		isc_if;
1757 	int			new_interface_found;
1758 	unsigned int		family;
1759 	endpt			enumep;
1760 	endpt *			ep;
1761 	endpt *			next_ep;
1762 
1763 	DPRINTF(3, ("update_interfaces(%d)\n", port));
1764 
1765 	/*
1766 	 * phase one - scan interfaces
1767 	 * - create those that are not found
1768 	 * - update those that are found
1769 	 */
1770 
1771 	new_interface_found = FALSE;
1772 	iter = NULL;
1773 	result = isc_interfaceiter_create(mctx, &iter);
1774 
1775 	if (result != ISC_R_SUCCESS)
1776 		return 0;
1777 
1778 	/*
1779 	 * Toggle system interface scan phase to find untouched
1780 	 * interfaces to be deleted.
1781 	 */
1782 	sys_interphase ^= 0x1;
1783 
1784 	for (result = isc_interfaceiter_first(iter);
1785 	     ISC_R_SUCCESS == result;
1786 	     result = isc_interfaceiter_next(iter)) {
1787 
1788 		result = isc_interfaceiter_current(iter, &isc_if);
1789 
1790 		if (result != ISC_R_SUCCESS)
1791 			break;
1792 
1793 		/* See if we have a valid family to use */
1794 		family = isc_if.address.family;
1795 		if (AF_INET != family && AF_INET6 != family)
1796 			continue;
1797 		if (AF_INET == family && !ipv4_works)
1798 			continue;
1799 		if (AF_INET6 == family && !ipv6_works)
1800 			continue;
1801 
1802 		/* create prototype */
1803 		init_interface(&enumep);
1804 
1805 		convert_isc_if(&isc_if, &enumep, port);
1806 
1807 		DPRINT_INTERFACE(4, (&enumep, "examining ", "\n"));
1808 
1809 		/*
1810 		 * Check if and how we are going to use the interface.
1811 		 */
1812 		switch (interface_action(enumep.name, &enumep.sin,
1813 					 enumep.flags)) {
1814 
1815 		case ACTION_IGNORE:
1816 			DPRINTF(4, ("ignoring interface %s (%s) - by nic rules\n",
1817 				    enumep.name, stoa(&enumep.sin)));
1818 			continue;
1819 
1820 		case ACTION_LISTEN:
1821 			DPRINTF(4, ("listen interface %s (%s) - by nic rules\n",
1822 				    enumep.name, stoa(&enumep.sin)));
1823 			enumep.ignore_packets = ISC_FALSE;
1824 			break;
1825 
1826 		case ACTION_DROP:
1827 			DPRINTF(4, ("drop on interface %s (%s) - by nic rules\n",
1828 				    enumep.name, stoa(&enumep.sin)));
1829 			enumep.ignore_packets = ISC_TRUE;
1830 			break;
1831 		}
1832 
1833 		 /* interfaces must be UP to be usable */
1834 		if (!(enumep.flags & INT_UP)) {
1835 			DPRINTF(4, ("skipping interface %s (%s) - DOWN\n",
1836 				    enumep.name, stoa(&enumep.sin)));
1837 			continue;
1838 		}
1839 
1840 		/*
1841 		 * skip any interfaces UP and bound to a wildcard
1842 		 * address - some dhcp clients produce that in the
1843 		 * wild
1844 		 */
1845 		if (is_wildcard_addr(&enumep.sin))
1846 			continue;
1847 
1848 		if (is_anycast(&enumep.sin, isc_if.name))
1849 			continue;
1850 
1851 		/*
1852 		 * skip any address that is an invalid state to be used
1853 		 */
1854 		if (!is_valid(&enumep.sin, isc_if.name))
1855 			continue;
1856 
1857 		/*
1858 		 * map to local *address* in order to map all duplicate
1859 		 * interfaces to an endpt structure with the appropriate
1860 		 * socket.  Our name space is (ip-address), NOT
1861 		 * (interface name, ip-address).
1862 		 */
1863 		ep = getinterface(&enumep.sin, INT_WILDCARD);
1864 
1865 		if (ep != NULL && refresh_interface(ep)) {
1866 			/*
1867 			 * found existing and up to date interface -
1868 			 * mark present.
1869 			 */
1870 			if (ep->phase != sys_interphase) {
1871 				/*
1872 				 * On a new round we reset the name so
1873 				 * the interface name shows up again if
1874 				 * this address is no longer shared.
1875 				 * We reset ignore_packets from the
1876 				 * new prototype to respect any runtime
1877 				 * changes to the nic rules.
1878 				 */
1879 				strlcpy(ep->name, enumep.name,
1880 					sizeof(ep->name));
1881 				ep->ignore_packets =
1882 					    enumep.ignore_packets;
1883 			} else {
1884 				/* name collision - rename interface */
1885 				strlcpy(ep->name, "*multiple*",
1886 					sizeof(ep->name));
1887 			}
1888 
1889 			DPRINT_INTERFACE(4, (ep, "updating ",
1890 					     " present\n"));
1891 
1892 			if (ep->ignore_packets !=
1893 			    enumep.ignore_packets) {
1894 				/*
1895 				 * We have conflicting configurations
1896 				 * for the interface address. This is
1897 				 * caused by using -I <interfacename>
1898 				 * for an interface that shares its
1899 				 * address with other interfaces. We
1900 				 * can not disambiguate incoming
1901 				 * packets delivered to this socket
1902 				 * without extra syscalls/features.
1903 				 * These are not (commonly) available.
1904 				 * Note this is a more unusual
1905 				 * configuration where several
1906 				 * interfaces share an address but
1907 				 * filtering via interface name is
1908 				 * attempted.  We resolve the
1909 				 * configuration conflict by disabling
1910 				 * the processing of received packets.
1911 				 * This leads to no service on the
1912 				 * interface address where the conflict
1913 				 * occurs.
1914 				 */
1915 				msyslog(LOG_ERR,
1916 					"WARNING: conflicting enable configuration for interfaces %s and %s for address %s - unsupported configuration - address DISABLED",
1917 					enumep.name, ep->name,
1918 					stoa(&enumep.sin));
1919 
1920 				ep->ignore_packets = ISC_TRUE;
1921 			}
1922 
1923 			ep->phase = sys_interphase;
1924 
1925 			ifi.action = IFS_EXISTS;
1926 			ifi.ep = ep;
1927 			if (receiver != NULL)
1928 				(*receiver)(data, &ifi);
1929 		} else {
1930 			/*
1931 			 * This is new or refreshing failed - add to
1932 			 * our interface list.  If refreshing failed we
1933 			 * will delete the interface structure in phase
1934 			 * 2 as the interface was not marked current.
1935 			 * We can bind to the address as the refresh
1936 			 * code already closed the offending socket
1937 			 */
1938 			ep = create_interface(port, &enumep);
1939 
1940 			if (ep != NULL) {
1941 				ifi.action = IFS_CREATED;
1942 				ifi.ep = ep;
1943 				if (receiver != NULL)
1944 					(*receiver)(data, &ifi);
1945 
1946 				new_interface_found = TRUE;
1947 				DPRINT_INTERFACE(3,
1948 					(ep, "updating ",
1949 					 " new - created\n"));
1950 			} else {
1951 				DPRINT_INTERFACE(3,
1952 					(&enumep, "updating ",
1953 					 " new - creation FAILED"));
1954 
1955 				msyslog(LOG_INFO,
1956 					"failed to init interface for address %s",
1957 					stoa(&enumep.sin));
1958 				continue;
1959 			}
1960 		}
1961 	}
1962 
1963 	isc_interfaceiter_destroy(&iter);
1964 
1965 	/*
1966 	 * phase 2 - delete gone interfaces - reassigning peers to
1967 	 * other interfaces
1968 	 */
1969 	for (ep = ep_list; ep != NULL; ep = next_ep) {
1970 		next_ep = ep->elink;
1971 
1972 		/*
1973 		 * if phase does not match sys_phase this interface was
1974 		 * not enumerated during the last interface scan - so it
1975 		 * is gone and will be deleted here unless it did not
1976 		 * originate from interface enumeration (INT_WILDCARD,
1977 		 * INT_MCASTIF).
1978 		 */
1979 		if (((INT_WILDCARD | INT_MCASTIF) & ep->flags) ||
1980 		    ep->phase == sys_interphase)
1981 			continue;
1982 
1983 		DPRINT_INTERFACE(3, (ep, "updating ",
1984 				     "GONE - deleting\n"));
1985 		remove_interface(ep);
1986 
1987 		ifi.action = IFS_DELETED;
1988 		ifi.ep = ep;
1989 		if (receiver != NULL)
1990 			(*receiver)(data, &ifi);
1991 
1992 		/* disconnect peers from deleted endpt. */
1993 		while (ep->peers != NULL)
1994 			set_peerdstadr(ep->peers, NULL);
1995 
1996 		/*
1997 		 * update globals in case we lose
1998 		 * a loopback interface
1999 		 */
2000 		if (ep == loopback_interface)
2001 			loopback_interface = NULL;
2002 
2003 		delete_interface(ep);
2004 	}
2005 
2006 	/*
2007 	 * phase 3 - re-configure as the world has possibly changed
2008 	 *
2009 	 * never ever make this conditional again - it is needed to track
2010 	 * routing updates. see bug #2506
2011 	 */
2012 	refresh_all_peerinterfaces();
2013 
2014 	if (broadcast_client_enabled || sys_bclient)
2015 		io_setbclient();
2016 
2017 #ifdef MCAST
2018 	/*
2019 	 * Check multicast interfaces and try to join multicast groups if
2020          * not joined yet.
2021          */
2022 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2023 		remaddr_t *entry;
2024 
2025 		if (!(INT_MCASTIF & ep->flags) || (INT_MCASTOPEN & ep->flags))
2026 			continue;
2027 
2028 		/* Find remote address that was linked to this interface */
2029 		for (entry = remoteaddr_list;
2030 		     entry != NULL;
2031 		     entry = entry->link) {
2032 			if (entry->ep == ep) {
2033 				if (socket_multicast_enable(ep, &entry->addr)) {
2034 					msyslog(LOG_INFO,
2035 						"Joined %s socket to multicast group %s",
2036 						stoa(&ep->sin),
2037 						stoa(&entry->addr));
2038 				}
2039 				break;
2040 			}
2041 		}
2042 	}
2043 #endif /* MCAST */
2044 
2045 	return new_interface_found;
2046 }
2047 
2048 
2049 /*
2050  * create_sockets - create a socket for each interface plus a default
2051  *			socket for when we don't know where to send
2052  */
2053 static int
2054 create_sockets(
2055 	u_short port
2056 	)
2057 {
2058 #ifndef HAVE_IO_COMPLETION_PORT
2059 	/*
2060 	 * I/O Completion Ports don't care about the select and FD_SET
2061 	 */
2062 	maxactivefd = 0;
2063 	FD_ZERO(&activefds);
2064 #endif
2065 
2066 	DPRINTF(2, ("create_sockets(%d)\n", port));
2067 
2068 	create_wildcards(port);
2069 
2070 	update_interfaces(port, NULL, NULL);
2071 
2072 	/*
2073 	 * Now that we have opened all the sockets, turn off the reuse
2074 	 * flag for security.
2075 	 */
2076 	set_reuseaddr(0);
2077 
2078 	DPRINTF(2, ("create_sockets: Total interfaces = %d\n", ninterfaces));
2079 
2080 	return ninterfaces;
2081 }
2082 
2083 /*
2084  * create_interface - create a new interface for a given prototype
2085  *		      binding the socket.
2086  */
2087 static struct interface *
2088 create_interface(
2089 	u_short			port,
2090 	struct interface *	protot
2091 	)
2092 {
2093 	sockaddr_u	resmask;
2094 	endpt *		iface;
2095 #if defined(MCAST) && defined(MULTICAST_NONEWSOCKET)
2096 	remaddr_t *	entry;
2097 	remaddr_t *	next_entry;
2098 #endif
2099 	DPRINTF(2, ("create_interface(%s#%d)\n", stoa(&protot->sin),
2100 		    port));
2101 
2102 	/* build an interface */
2103 	iface = new_interface(protot);
2104 
2105 	/*
2106 	 * create socket
2107 	 */
2108 	iface->fd = open_socket(&iface->sin, 0, 0, iface);
2109 
2110 	if (iface->fd != INVALID_SOCKET)
2111 		log_listen_address(iface);
2112 
2113 	if ((INT_BROADCAST & iface->flags)
2114 	    && iface->bfd != INVALID_SOCKET)
2115 		msyslog(LOG_INFO, "Listening on broadcast address %s#%d",
2116 			stoa((&iface->bcast)), port);
2117 
2118 	if (INVALID_SOCKET == iface->fd
2119 	    && INVALID_SOCKET == iface->bfd) {
2120 		msyslog(LOG_ERR, "unable to create socket on %s (%d) for %s#%d",
2121 			iface->name,
2122 			iface->ifnum,
2123 			stoa((&iface->sin)),
2124 			port);
2125 		delete_interface(iface);
2126 		return NULL;
2127 	}
2128 
2129 	/*
2130 	 * Blacklist our own addresses, no use talking to ourself
2131 	 */
2132 	SET_HOSTMASK(&resmask, AF(&iface->sin));
2133 	hack_restrict(RESTRICT_FLAGS, &iface->sin, &resmask,
2134 		      -4, RESM_NTPONLY | RESM_INTERFACE, RES_IGNORE, 0);
2135 
2136 	/*
2137 	 * set globals with the first found
2138 	 * loopback interface of the appropriate class
2139 	 */
2140 	if (NULL == loopback_interface && AF_INET == iface->family
2141 	    && (INT_LOOPBACK & iface->flags))
2142 		loopback_interface = iface;
2143 
2144 	/*
2145 	 * put into our interface list
2146 	 */
2147 	add_addr_to_list(&iface->sin, iface);
2148 	add_interface(iface);
2149 
2150 #if defined(MCAST) && defined(MULTICAST_NONEWSOCKET)
2151 	/*
2152 	 * Join any previously-configured compatible multicast groups.
2153 	 */
2154 	if (INT_MULTICAST & iface->flags &&
2155 	    !((INT_LOOPBACK | INT_WILDCARD) & iface->flags) &&
2156 	    !iface->ignore_packets) {
2157 		for (entry = remoteaddr_list;
2158 		     entry != NULL;
2159 		     entry = next_entry) {
2160 			next_entry = entry->link;
2161 			if (AF(&iface->sin) != AF(&entry->addr) ||
2162 			    !IS_MCAST(&entry->addr))
2163 				continue;
2164 			if (socket_multicast_enable(iface,
2165 						    &entry->addr))
2166 				msyslog(LOG_INFO,
2167 					"Joined %s socket to multicast group %s",
2168 					stoa(&iface->sin),
2169 					stoa(&entry->addr));
2170 			else
2171 				msyslog(LOG_ERR,
2172 					"Failed to join %s socket to multicast group %s",
2173 					stoa(&iface->sin),
2174 					stoa(&entry->addr));
2175 		}
2176 	}
2177 #endif	/* MCAST && MCAST_NONEWSOCKET */
2178 
2179 	DPRINT_INTERFACE(2, (iface, "created ", "\n"));
2180 	return iface;
2181 }
2182 
2183 
2184 #ifdef SO_EXCLUSIVEADDRUSE
2185 static void
2186 set_excladdruse(
2187 	SOCKET fd
2188 	)
2189 {
2190 	int one = 1;
2191 	int failed;
2192 #ifdef SYS_WINNT
2193 	DWORD err;
2194 #endif
2195 
2196 	failed = setsockopt(fd, SOL_SOCKET, SO_EXCLUSIVEADDRUSE,
2197 			    (void *)&one, sizeof(one));
2198 
2199 	if (!failed)
2200 		return;
2201 
2202 #ifdef SYS_WINNT
2203 	/*
2204 	 * Prior to Windows XP setting SO_EXCLUSIVEADDRUSE can fail with
2205 	 * error WSAINVAL depending on service pack level and whether
2206 	 * the user account is in the Administrators group.  Do not
2207 	 * complain if it fails that way on versions prior to XP (5.1).
2208 	 */
2209 	err = GetLastError();
2210 
2211 	if (isc_win32os_versioncheck(5, 1, 0, 0) < 0	/* < 5.1/XP */
2212 	    && WSAEINVAL == err)
2213 		return;
2214 
2215 	SetLastError(err);
2216 #endif
2217 	msyslog(LOG_ERR,
2218 		"setsockopt(%d, SO_EXCLUSIVEADDRUSE, on): %m",
2219 		(int)fd);
2220 }
2221 #endif  /* SO_EXCLUSIVEADDRUSE */
2222 
2223 
2224 /*
2225  * set_reuseaddr() - set/clear REUSEADDR on all sockets
2226  *			NB possible hole - should we be doing this on broadcast
2227  *			fd's also?
2228  */
2229 static void
2230 set_reuseaddr(
2231 	int flag
2232 	)
2233 {
2234 #ifndef SO_EXCLUSIVEADDRUSE
2235 	endpt *ep;
2236 
2237 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2238 		if (ep->flags & INT_WILDCARD)
2239 			continue;
2240 
2241 		/*
2242 		 * if ep->fd  is INVALID_SOCKET, we might have a adapter
2243 		 * configured but not present
2244 		 */
2245 		DPRINTF(4, ("setting SO_REUSEADDR on %.16s@%s to %s\n",
2246 			    ep->name, stoa(&ep->sin),
2247 			    flag ? "on" : "off"));
2248 
2249 		if (ep->fd != INVALID_SOCKET) {
2250 			if (setsockopt(ep->fd, SOL_SOCKET, SO_REUSEADDR,
2251 				       (void *)&flag, sizeof(flag))) {
2252 				msyslog(LOG_ERR, "set_reuseaddr: setsockopt(%s, SO_REUSEADDR, %s) failed: %m",
2253 					stoa(&ep->sin), flag ? "on" : "off");
2254 			}
2255 		}
2256 	}
2257 #endif /* ! SO_EXCLUSIVEADDRUSE */
2258 }
2259 
2260 /*
2261  * This is just a wrapper around an internal function so we can
2262  * make other changes as necessary later on
2263  */
2264 void
2265 enable_broadcast(
2266 	struct interface *	iface,
2267 	sockaddr_u *		baddr
2268 	)
2269 {
2270 #ifdef OPEN_BCAST_SOCKET
2271 	socket_broadcast_enable(iface, iface->fd, baddr);
2272 #endif
2273 }
2274 
2275 #ifdef OPEN_BCAST_SOCKET
2276 /*
2277  * Enable a broadcast address to a given socket
2278  * The socket is in the ep_list all we need to do is enable
2279  * broadcasting. It is not this function's job to select the socket
2280  */
2281 static isc_boolean_t
2282 socket_broadcast_enable(
2283 	struct interface *	iface,
2284 	SOCKET			fd,
2285 	sockaddr_u *		baddr
2286 	)
2287 {
2288 #ifdef SO_BROADCAST
2289 	int on = 1;
2290 
2291 	if (IS_IPV4(baddr)) {
2292 		/* if this interface can support broadcast, set SO_BROADCAST */
2293 		if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST,
2294 			       (void *)&on, sizeof(on)))
2295 			msyslog(LOG_ERR,
2296 				"setsockopt(SO_BROADCAST) enable failure on address %s: %m",
2297 				stoa(baddr));
2298 		else
2299 			DPRINTF(2, ("Broadcast enabled on socket %d for address %s\n",
2300 				    fd, stoa(baddr)));
2301 	}
2302 	iface->flags |= INT_BCASTXMIT;
2303 	return ISC_TRUE;
2304 #else
2305 	return ISC_FALSE;
2306 #endif /* SO_BROADCAST */
2307 }
2308 
2309 #ifdef  OS_MISSES_SPECIFIC_ROUTE_UPDATES
2310 /*
2311  * Remove a broadcast address from a given socket
2312  * The socket is in the ep_list all we need to do is disable
2313  * broadcasting. It is not this function's job to select the socket
2314  */
2315 static isc_boolean_t
2316 socket_broadcast_disable(
2317 	struct interface *	iface,
2318 	sockaddr_u *		baddr
2319 	)
2320 {
2321 #ifdef SO_BROADCAST
2322 	int off = 0;	/* This seems to be OK as an int */
2323 
2324 	if (IS_IPV4(baddr) && setsockopt(iface->fd, SOL_SOCKET,
2325 	    SO_BROADCAST, (void *)&off, sizeof(off)))
2326 		msyslog(LOG_ERR,
2327 			"setsockopt(SO_BROADCAST) disable failure on address %s: %m",
2328 			stoa(baddr));
2329 
2330 	iface->flags &= ~INT_BCASTXMIT;
2331 	return ISC_TRUE;
2332 #else
2333 	return ISC_FALSE;
2334 #endif /* SO_BROADCAST */
2335 }
2336 #endif /* OS_MISSES_SPECIFIC_ROUTE_UPDATES */
2337 
2338 #endif /* OPEN_BCAST_SOCKET */
2339 
2340 /*
2341  * return the broadcast client flag value
2342  */
2343 /*isc_boolean_t
2344 get_broadcastclient_flag(void)
2345 {
2346 	return (broadcast_client_enabled);
2347 }
2348 */
2349 
2350 /*
2351  * Check to see if the address is a multicast address
2352  */
2353 static isc_boolean_t
2354 addr_ismulticast(
2355 	sockaddr_u *maddr
2356 	)
2357 {
2358 	isc_boolean_t result;
2359 
2360 #ifndef INCLUDE_IPV6_MULTICAST_SUPPORT
2361 	/*
2362 	 * If we don't have IPV6 support any IPV6 addr is not multicast
2363 	 */
2364 	if (IS_IPV6(maddr))
2365 		result = ISC_FALSE;
2366 	else
2367 #endif
2368 		result = IS_MCAST(maddr);
2369 
2370 	if (!result)
2371 		DPRINTF(4, ("address %s is not multicast\n",
2372 			    stoa(maddr)));
2373 
2374 	return result;
2375 }
2376 
2377 /*
2378  * Multicast servers need to set the appropriate Multicast interface
2379  * socket option in order for it to know which interface to use for
2380  * send the multicast packet.
2381  */
2382 void
2383 enable_multicast_if(
2384 	struct interface *	iface,
2385 	sockaddr_u *		maddr
2386 	)
2387 {
2388 #ifdef MCAST
2389 #ifdef IP_MULTICAST_LOOP
2390 	TYPEOF_IP_MULTICAST_LOOP off = 0;
2391 #endif
2392 #if defined(INCLUDE_IPV6_MULTICAST_SUPPORT) && defined(IPV6_MULTICAST_LOOP)
2393 	u_int off6 = 0;
2394 #endif
2395 
2396 	REQUIRE(AF(maddr) == AF(&iface->sin));
2397 
2398 	switch (AF(&iface->sin)) {
2399 
2400 	case AF_INET:
2401 #ifdef IP_MULTICAST_LOOP
2402 		/*
2403 		 * Don't send back to itself, but allow failure to set
2404 		 */
2405 		if (setsockopt(iface->fd, IPPROTO_IP,
2406 			       IP_MULTICAST_LOOP,
2407 			       (void *)&off,
2408 			       sizeof(off))) {
2409 
2410 			msyslog(LOG_ERR,
2411 				"setsockopt IP_MULTICAST_LOOP failed: %m on socket %d, addr %s for multicast address %s",
2412 				iface->fd, stoa(&iface->sin),
2413 				stoa(maddr));
2414 		}
2415 #endif
2416 		break;
2417 
2418 	case AF_INET6:
2419 #ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2420 #ifdef IPV6_MULTICAST_LOOP
2421 		/*
2422 		 * Don't send back to itself, but allow failure to set
2423 		 */
2424 		if (setsockopt(iface->fd, IPPROTO_IPV6,
2425 			       IPV6_MULTICAST_LOOP,
2426 			       (void *) &off6, sizeof(off6))) {
2427 
2428 			msyslog(LOG_ERR,
2429 				"setsockopt IPV6_MULTICAST_LOOP failed: %m on socket %d, addr %s for multicast address %s",
2430 				iface->fd, stoa(&iface->sin),
2431 				stoa(maddr));
2432 		}
2433 #endif
2434 		break;
2435 #else
2436 		return;
2437 #endif	/* INCLUDE_IPV6_MULTICAST_SUPPORT */
2438 	}
2439 	return;
2440 #endif
2441 }
2442 
2443 /*
2444  * Add a multicast address to a given socket
2445  * The socket is in the ep_list all we need to do is enable
2446  * multicasting. It is not this function's job to select the socket
2447  */
2448 #if defined(MCAST)
2449 static isc_boolean_t
2450 socket_multicast_enable(
2451 	endpt *		iface,
2452 	sockaddr_u *	maddr
2453 	)
2454 {
2455 	struct ip_mreq		mreq;
2456 # ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2457 	struct ipv6_mreq	mreq6;
2458 # endif
2459 	switch (AF(maddr)) {
2460 
2461 	case AF_INET:
2462 		ZERO(mreq);
2463 		mreq.imr_multiaddr = SOCK_ADDR4(maddr);
2464 		mreq.imr_interface.s_addr = htonl(INADDR_ANY);
2465 		if (setsockopt(iface->fd,
2466 			       IPPROTO_IP,
2467 			       IP_ADD_MEMBERSHIP,
2468 			       (void *)&mreq,
2469 			       sizeof(mreq))) {
2470 			DPRINTF(2, (
2471 				"setsockopt IP_ADD_MEMBERSHIP failed: %m on socket %d, addr %s for %x / %x (%s)",
2472 				iface->fd, stoa(&iface->sin),
2473 				mreq.imr_multiaddr.s_addr,
2474 				mreq.imr_interface.s_addr,
2475 				stoa(maddr)));
2476 			return ISC_FALSE;
2477 		}
2478 		DPRINTF(4, ("Added IPv4 multicast membership on socket %d, addr %s for %x / %x (%s)\n",
2479 			    iface->fd, stoa(&iface->sin),
2480 			    mreq.imr_multiaddr.s_addr,
2481 			    mreq.imr_interface.s_addr, stoa(maddr)));
2482 		break;
2483 
2484 	case AF_INET6:
2485 # ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2486 		/*
2487 		 * Enable reception of multicast packets.
2488 		 * If the address is link-local we can get the
2489 		 * interface index from the scope id. Don't do this
2490 		 * for other types of multicast addresses. For now let
2491 		 * the kernel figure it out.
2492 		 */
2493 		ZERO(mreq6);
2494 		mreq6.ipv6mr_multiaddr = SOCK_ADDR6(maddr);
2495 		mreq6.ipv6mr_interface = iface->ifindex;
2496 
2497 		if (setsockopt(iface->fd, IPPROTO_IPV6,
2498 			       IPV6_JOIN_GROUP, (void *)&mreq6,
2499 			       sizeof(mreq6))) {
2500 			DPRINTF(2, (
2501 				"setsockopt IPV6_JOIN_GROUP failed: %m on socket %d, addr %s for interface %u (%s)",
2502 				iface->fd, stoa(&iface->sin),
2503 				mreq6.ipv6mr_interface, stoa(maddr)));
2504 			return ISC_FALSE;
2505 		}
2506 		DPRINTF(4, ("Added IPv6 multicast group on socket %d, addr %s for interface %u (%s)\n",
2507 			    iface->fd, stoa(&iface->sin),
2508 			    mreq6.ipv6mr_interface, stoa(maddr)));
2509 # else
2510 		return ISC_FALSE;
2511 # endif	/* INCLUDE_IPV6_MULTICAST_SUPPORT */
2512 	}
2513 	iface->flags |= INT_MCASTOPEN;
2514 	iface->num_mcast++;
2515 
2516 	return ISC_TRUE;
2517 }
2518 #endif	/* MCAST */
2519 
2520 
2521 /*
2522  * Remove a multicast address from a given socket
2523  * The socket is in the ep_list all we need to do is disable
2524  * multicasting. It is not this function's job to select the socket
2525  */
2526 #ifdef MCAST
2527 static isc_boolean_t
2528 socket_multicast_disable(
2529 	struct interface *	iface,
2530 	sockaddr_u *		maddr
2531 	)
2532 {
2533 # ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2534 	struct ipv6_mreq mreq6;
2535 # endif
2536 	struct ip_mreq mreq;
2537 
2538 	ZERO(mreq);
2539 
2540 	if (find_addr_in_list(maddr) == NULL) {
2541 		DPRINTF(4, ("socket_multicast_disable(%s): not found\n",
2542 			    stoa(maddr)));
2543 		return ISC_TRUE;
2544 	}
2545 
2546 	switch (AF(maddr)) {
2547 
2548 	case AF_INET:
2549 		mreq.imr_multiaddr = SOCK_ADDR4(maddr);
2550 		mreq.imr_interface = SOCK_ADDR4(&iface->sin);
2551 		if (setsockopt(iface->fd, IPPROTO_IP,
2552 			       IP_DROP_MEMBERSHIP, (void *)&mreq,
2553 			       sizeof(mreq))) {
2554 
2555 			msyslog(LOG_ERR,
2556 				"setsockopt IP_DROP_MEMBERSHIP failed: %m on socket %d, addr %s for %x / %x (%s)",
2557 				iface->fd, stoa(&iface->sin),
2558 				SRCADR(maddr), SRCADR(&iface->sin),
2559 				stoa(maddr));
2560 			return ISC_FALSE;
2561 		}
2562 		break;
2563 	case AF_INET6:
2564 # ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
2565 		/*
2566 		 * Disable reception of multicast packets
2567 		 * If the address is link-local we can get the
2568 		 * interface index from the scope id.  Don't do this
2569 		 * for other types of multicast addresses. For now let
2570 		 * the kernel figure it out.
2571 		 */
2572 		mreq6.ipv6mr_multiaddr = SOCK_ADDR6(maddr);
2573 		mreq6.ipv6mr_interface = iface->ifindex;
2574 
2575 		if (setsockopt(iface->fd, IPPROTO_IPV6,
2576 			       IPV6_LEAVE_GROUP, (void *)&mreq6,
2577 			       sizeof(mreq6))) {
2578 
2579 			msyslog(LOG_ERR,
2580 				"setsockopt IPV6_LEAVE_GROUP failure: %m on socket %d, addr %s for %d (%s)",
2581 				iface->fd, stoa(&iface->sin),
2582 				iface->ifindex, stoa(maddr));
2583 			return ISC_FALSE;
2584 		}
2585 		break;
2586 # else
2587 		return ISC_FALSE;
2588 # endif	/* INCLUDE_IPV6_MULTICAST_SUPPORT */
2589 	}
2590 
2591 	iface->num_mcast--;
2592 	if (!iface->num_mcast)
2593 		iface->flags &= ~INT_MCASTOPEN;
2594 
2595 	return ISC_TRUE;
2596 }
2597 #endif	/* MCAST */
2598 
2599 /*
2600  * io_setbclient - open the broadcast client sockets
2601  */
2602 void
2603 io_setbclient(void)
2604 {
2605 #ifdef OPEN_BCAST_SOCKET
2606 	endpt *		ep;
2607 	unsigned int	nif, ni4, ni6;
2608 
2609 	nif = ni4 = ni6 = 0;
2610 	set_reuseaddr(1);
2611 
2612 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2613 		/* count IPv6 vs IPv4 interfaces. Needed later to decide
2614 		 * if we should log an error or not.
2615 		 */
2616 		switch (ep->family) {
2617 		case AF_INET : ++ni4; break;
2618 		case AF_INET6: ++ni6; break;
2619 		default      :        break;
2620 		}
2621 
2622 		if (ep->flags & (INT_WILDCARD | INT_LOOPBACK))
2623 			continue;
2624 
2625 		/* use only allowed addresses */
2626 		if (ep->ignore_packets)
2627 			continue;
2628 
2629 		/* Need a broadcast-capable interface */
2630 		if (!(ep->flags & INT_BROADCAST))
2631 			continue;
2632 
2633 		/* Only IPv4 addresses are valid for broadcast */
2634 		REQUIRE(IS_IPV4(&ep->bcast));
2635 
2636 		/* Do we already have the broadcast address open? */
2637 		if (ep->flags & INT_BCASTOPEN) {
2638 			/*
2639 			 * account for already open interfaces to avoid
2640 			 * misleading warning below
2641 			 */
2642 			nif++;
2643 			continue;
2644 		}
2645 
2646 		/*
2647 		 * Try to open the broadcast address
2648 		 */
2649 		ep->family = AF_INET;
2650 		ep->bfd = open_socket(&ep->bcast, 1, 0, ep);
2651 
2652 		/*
2653 		 * If we succeeded then we use it otherwise enable
2654 		 * broadcast on the interface address
2655 		 */
2656 		if (ep->bfd != INVALID_SOCKET) {
2657 			nif++;
2658 			ep->flags |= INT_BCASTOPEN;
2659 			msyslog(LOG_INFO,
2660 				"Listen for broadcasts to %s on interface #%d %s",
2661 				stoa(&ep->bcast), ep->ifnum, ep->name);
2662 		} else switch (errno) {
2663 			/* Silently ignore EADDRINUSE as we probably
2664 			 * opened the socket already for an address in
2665 			 * the same network */
2666 		case EADDRINUSE:
2667 			/* Some systems cannot bind a socket to a broadcast
2668 			 * address, as that is not a valid host address. */
2669 		case EADDRNOTAVAIL:
2670 #		    ifdef SYS_WINNT	/*TODO: use for other systems, too? */
2671 			/* avoid recurrence here -- if we already have a
2672 			 * regular socket, it's quite useless to try this
2673 			 * again.
2674 			 */
2675 			if (ep->fd != INVALID_SOCKET) {
2676 				ep->flags |= INT_BCASTOPEN;
2677 				nif++;
2678 			}
2679 #		    endif
2680 			break;
2681 
2682 		default:
2683 			msyslog(LOG_INFO,
2684 				"failed to listen for broadcasts to %s on interface #%d %s",
2685 				stoa(&ep->bcast), ep->ifnum, ep->name);
2686 			break;
2687 		}
2688 	}
2689 	set_reuseaddr(0);
2690 	if (nif != 0) {
2691 		broadcast_client_enabled = ISC_TRUE;
2692 		DPRINTF(1, ("io_setbclient: listening to %d broadcast addresses\n", nif));
2693 	} else {
2694 		broadcast_client_enabled = ISC_FALSE;
2695 		/* This is expected when having only IPv6 interfaces
2696 		 * and no IPv4 interfaces at all. We suppress the error
2697 		 * log in that case... everything else should work!
2698 		 */
2699 		if (ni4 && !ni6) {
2700 			msyslog(LOG_ERR,
2701 				"Unable to listen for broadcasts, no broadcast interfaces available");
2702 		}
2703 	}
2704 #else
2705 	msyslog(LOG_ERR,
2706 		"io_setbclient: Broadcast Client disabled by build");
2707 #endif	/* OPEN_BCAST_SOCKET */
2708 }
2709 
2710 /*
2711  * io_unsetbclient - close the broadcast client sockets
2712  */
2713 void
2714 io_unsetbclient(void)
2715 {
2716 	endpt *ep;
2717 
2718 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2719 		if (INT_WILDCARD & ep->flags)
2720 			continue;
2721 		if (!(INT_BCASTOPEN & ep->flags))
2722 			continue;
2723 
2724 		if (ep->bfd != INVALID_SOCKET) {
2725 			/* destroy broadcast listening socket */
2726 			msyslog(LOG_INFO,
2727 				"stop listening for broadcasts to %s on interface #%d %s",
2728 				stoa(&ep->bcast), ep->ifnum, ep->name);
2729 #		    ifdef HAVE_IO_COMPLETION_PORT
2730 			io_completion_port_remove_socket(ep->bfd, ep);
2731 #		    endif
2732 			close_and_delete_fd_from_list(ep->bfd);
2733 			ep->bfd = INVALID_SOCKET;
2734 		}
2735 		ep->flags &= ~INT_BCASTOPEN;
2736 	}
2737 	broadcast_client_enabled = ISC_FALSE;
2738 }
2739 
2740 /*
2741  * io_multicast_add() - add multicast group address
2742  */
2743 void
2744 io_multicast_add(
2745 	sockaddr_u *addr
2746 	)
2747 {
2748 #ifdef MCAST
2749 	endpt *	ep;
2750 	endpt *	one_ep;
2751 
2752 	/*
2753 	 * Check to see if this is a multicast address
2754 	 */
2755 	if (!addr_ismulticast(addr))
2756 		return;
2757 
2758 	/* If we already have it we can just return */
2759 	if (NULL != find_flagged_addr_in_list(addr, INT_MCASTOPEN)) {
2760 		msyslog(LOG_INFO,
2761 			"Duplicate request found for multicast address %s",
2762 			stoa(addr));
2763 		return;
2764 	}
2765 
2766 # ifndef MULTICAST_NONEWSOCKET
2767 	ep = new_interface(NULL);
2768 
2769 	/*
2770 	 * Open a new socket for the multicast address
2771 	 */
2772 	ep->sin = *addr;
2773 	SET_PORT(&ep->sin, NTP_PORT);
2774 	ep->family = AF(&ep->sin);
2775 	AF(&ep->mask) = ep->family;
2776 	SET_ONESMASK(&ep->mask);
2777 
2778 	set_reuseaddr(1);
2779 	ep->bfd = INVALID_SOCKET;
2780 	ep->fd = open_socket(&ep->sin, 0, 0, ep);
2781 	if (ep->fd != INVALID_SOCKET) {
2782 		ep->ignore_packets = ISC_FALSE;
2783 		ep->flags |= INT_MCASTIF;
2784 		ep->ifindex = SCOPE(addr);
2785 
2786 		strlcpy(ep->name, "multicast", sizeof(ep->name));
2787 		DPRINT_INTERFACE(2, (ep, "multicast add ", "\n"));
2788 		add_interface(ep);
2789 		log_listen_address(ep);
2790 	} else {
2791 		/* bind failed, re-use wildcard interface */
2792 		delete_interface(ep);
2793 
2794 		if (IS_IPV4(addr))
2795 			ep = wildipv4;
2796 		else if (IS_IPV6(addr))
2797 			ep = wildipv6;
2798 		else
2799 			ep = NULL;
2800 
2801 		if (ep != NULL) {
2802 			/* HACK ! -- stuff in an address */
2803 			/* because we don't bind addr? DH */
2804 			ep->bcast = *addr;
2805 			msyslog(LOG_ERR,
2806 				"multicast address %s using wildcard interface #%d %s",
2807 				stoa(addr), ep->ifnum, ep->name);
2808 		} else {
2809 			msyslog(LOG_ERR,
2810 				"No multicast socket available to use for address %s",
2811 				stoa(addr));
2812 			return;
2813 		}
2814 	}
2815 	{	/* in place of the { following for in #else clause */
2816 		one_ep = ep;
2817 # else	/* MULTICAST_NONEWSOCKET follows */
2818 	/*
2819 	 * For the case where we can't use a separate socket (Windows)
2820 	 * join each applicable endpoint socket to the group address.
2821 	 */
2822 	if (IS_IPV4(addr))
2823 		one_ep = wildipv4;
2824 	else
2825 		one_ep = wildipv6;
2826 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
2827 		if (ep->ignore_packets || AF(&ep->sin) != AF(addr) ||
2828 		    !(INT_MULTICAST & ep->flags) ||
2829 		    (INT_LOOPBACK | INT_WILDCARD) & ep->flags)
2830 			continue;
2831 		one_ep = ep;
2832 # endif	/* MULTICAST_NONEWSOCKET */
2833 		if (socket_multicast_enable(ep, addr))
2834 			msyslog(LOG_INFO,
2835 				"Joined %s socket to multicast group %s",
2836 				stoa(&ep->sin),
2837 				stoa(addr));
2838 	}
2839 
2840 	add_addr_to_list(addr, one_ep);
2841 #else	/* !MCAST  follows*/
2842 	msyslog(LOG_ERR,
2843 		"Can not add multicast address %s: no multicast support",
2844 		stoa(addr));
2845 #endif
2846 	return;
2847 }
2848 
2849 
2850 /*
2851  * io_multicast_del() - delete multicast group address
2852  */
2853 void
2854 io_multicast_del(
2855 	sockaddr_u *	addr
2856 	)
2857 {
2858 #ifdef MCAST
2859 	endpt *iface;
2860 
2861 	/*
2862 	 * Check to see if this is a multicast address
2863 	 */
2864 	if (!addr_ismulticast(addr)) {
2865 		msyslog(LOG_ERR, "invalid multicast address %s",
2866 			stoa(addr));
2867 		return;
2868 	}
2869 
2870 	/*
2871 	 * Disable reception of multicast packets
2872 	 */
2873 	while ((iface = find_flagged_addr_in_list(addr, INT_MCASTOPEN))
2874 	       != NULL)
2875 		socket_multicast_disable(iface, addr);
2876 
2877 	delete_addr_from_list(addr);
2878 
2879 #else /* not MCAST */
2880 	msyslog(LOG_ERR,
2881 		"Can not delete multicast address %s: no multicast support",
2882 		stoa(addr));
2883 #endif /* not MCAST */
2884 }
2885 
2886 
2887 /*
2888  * open_socket - open a socket, returning the file descriptor
2889  */
2890 
2891 static SOCKET
2892 open_socket(
2893 	sockaddr_u *	addr,
2894 	int		bcast,
2895 	int		turn_off_reuse,
2896 	endpt *		interf
2897 	)
2898 {
2899 	SOCKET	fd;
2900 	int	errval;
2901 	/*
2902 	 * int is OK for REUSEADR per
2903 	 * http://www.kohala.com/start/mcast.api.txt
2904 	 */
2905 	int	on = 1;
2906 	int	off = 0;
2907 
2908 	if (IS_IPV6(addr) && !ipv6_works)
2909 		return INVALID_SOCKET;
2910 
2911 	/* create a datagram (UDP) socket */
2912 	fd = socket(AF(addr), SOCK_DGRAM, 0);
2913 	if (INVALID_SOCKET == fd) {
2914 		errval = socket_errno();
2915 		msyslog(LOG_ERR,
2916 			"socket(AF_INET%s, SOCK_DGRAM, 0) failed on address %s: %m",
2917 			IS_IPV6(addr) ? "6" : "", stoa(addr));
2918 
2919 		if (errval == EPROTONOSUPPORT ||
2920 		    errval == EAFNOSUPPORT ||
2921 		    errval == EPFNOSUPPORT)
2922 			return (INVALID_SOCKET);
2923 
2924 		errno = errval;
2925 		msyslog(LOG_ERR,
2926 			"unexpected socket() error %m code %d (not EPROTONOSUPPORT nor EAFNOSUPPORT nor EPFNOSUPPORT) - exiting",
2927 			errno);
2928 		exit(1);
2929 	}
2930 
2931 #ifdef SYS_WINNT
2932 	connection_reset_fix(fd, addr);
2933 #endif
2934 	/*
2935 	 * Fixup the file descriptor for some systems
2936 	 * See bug #530 for details of the issue.
2937 	 */
2938 	fd = move_fd(fd);
2939 
2940 	/*
2941 	 * set SO_REUSEADDR since we will be binding the same port
2942 	 * number on each interface according to turn_off_reuse.
2943 	 * This is undesirable on Windows versions starting with
2944 	 * Windows XP (numeric version 5.1).
2945 	 */
2946 #ifdef SYS_WINNT
2947 	if (isc_win32os_versioncheck(5, 1, 0, 0) < 0)  /* before 5.1 */
2948 #endif
2949 		if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
2950 			       (void *)((turn_off_reuse)
2951 					    ? &off
2952 					    : &on),
2953 			       sizeof(on))) {
2954 
2955 			msyslog(LOG_ERR,
2956 				"setsockopt SO_REUSEADDR %s fails for address %s: %m",
2957 				(turn_off_reuse)
2958 				    ? "off"
2959 				    : "on",
2960 				stoa(addr));
2961 			closesocket(fd);
2962 			return INVALID_SOCKET;
2963 		}
2964 #ifdef SO_EXCLUSIVEADDRUSE
2965 	/*
2966 	 * setting SO_EXCLUSIVEADDRUSE on the wildcard we open
2967 	 * first will cause more specific binds to fail.
2968 	 */
2969 	if (!(interf->flags & INT_WILDCARD))
2970 		set_excladdruse(fd);
2971 #endif
2972 
2973 	/*
2974 	 * IPv4 specific options go here
2975 	 */
2976 	if (IS_IPV4(addr)) {
2977 #if defined(IPPROTO_IP) && defined(IP_TOS)
2978 		if (setsockopt(fd, IPPROTO_IP, IP_TOS, (void *)&qos,
2979 			       sizeof(qos)))
2980 			msyslog(LOG_ERR,
2981 				"setsockopt IP_TOS (%02x) fails on address %s: %m",
2982 				qos, stoa(addr));
2983 #endif /* IPPROTO_IP && IP_TOS */
2984 		if (bcast)
2985 			socket_broadcast_enable(interf, fd, addr);
2986 	}
2987 
2988 	/*
2989 	 * IPv6 specific options go here
2990 	 */
2991 	if (IS_IPV6(addr)) {
2992 #if defined(IPPROTO_IPV6) && defined(IPV6_TCLASS)
2993 		if (setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS, (void *)&qos,
2994 			       sizeof(qos)))
2995 			msyslog(LOG_ERR,
2996 				"setsockopt IPV6_TCLASS (%02x) fails on address %s: %m",
2997 				qos, stoa(addr));
2998 #endif /* IPPROTO_IPV6 && IPV6_TCLASS */
2999 #ifdef IPV6_V6ONLY
3000 		if (isc_net_probe_ipv6only() == ISC_R_SUCCESS
3001 		    && setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY,
3002 		    (void *)&on, sizeof(on)))
3003 			msyslog(LOG_ERR,
3004 				"setsockopt IPV6_V6ONLY on fails on address %s: %m",
3005 				stoa(addr));
3006 #endif
3007 #ifdef IPV6_BINDV6ONLY
3008 		if (setsockopt(fd, IPPROTO_IPV6, IPV6_BINDV6ONLY,
3009 		    (void *)&on, sizeof(on)))
3010 			msyslog(LOG_ERR,
3011 				"setsockopt IPV6_BINDV6ONLY on fails on address %s: %m",
3012 				stoa(addr));
3013 #endif
3014 	}
3015 
3016 #ifdef OS_NEEDS_REUSEADDR_FOR_IFADDRBIND
3017 	/*
3018 	 * some OSes don't allow binding to more specific
3019 	 * addresses if a wildcard address already bound
3020 	 * to the port and SO_REUSEADDR is not set
3021 	 */
3022 	if (!is_wildcard_addr(addr))
3023 		set_wildcard_reuse(AF(addr), 1);
3024 #endif
3025 
3026 	/*
3027 	 * bind the local address.
3028 	 */
3029 	errval = bind(fd, &addr->sa, SOCKLEN(addr));
3030 
3031 #ifdef OS_NEEDS_REUSEADDR_FOR_IFADDRBIND
3032 	if (!is_wildcard_addr(addr))
3033 		set_wildcard_reuse(AF(addr), 0);
3034 #endif
3035 
3036 	if (errval < 0) {
3037 		/*
3038 		 * Don't log this under all conditions
3039 		 */
3040 		if (turn_off_reuse == 0
3041 #ifdef DEBUG
3042 		    || debug > 1
3043 #endif
3044 		    ) {
3045 			msyslog(LOG_ERR,
3046 				"bind(%d) AF_INET%s %s#%d%s flags 0x%x failed: %m",
3047 				fd, IS_IPV6(addr) ? "6" : "",
3048 				stoa(addr), SRCPORT(addr),
3049 				IS_MCAST(addr) ? " (multicast)" : "",
3050 				interf->flags);
3051 		}
3052 
3053 		closesocket(fd);
3054 
3055 		return INVALID_SOCKET;
3056 	}
3057 
3058 #ifdef HAVE_TIMESTAMP
3059 	{
3060 		if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMP,
3061 			       (void *)&on, sizeof(on)))
3062 			msyslog(LOG_DEBUG,
3063 				"setsockopt SO_TIMESTAMP on fails on address %s: %m",
3064 				stoa(addr));
3065 		else
3066 			DPRINTF(4, ("setsockopt SO_TIMESTAMP enabled on fd %d address %s\n",
3067 				    fd, stoa(addr)));
3068 	}
3069 #endif
3070 #ifdef HAVE_TIMESTAMPNS
3071 	{
3072 		if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPNS,
3073 			       (void *)&on, sizeof(on)))
3074 			msyslog(LOG_DEBUG,
3075 				"setsockopt SO_TIMESTAMPNS on fails on address %s: %m",
3076 				stoa(addr));
3077 		else
3078 			DPRINTF(4, ("setsockopt SO_TIMESTAMPNS enabled on fd %d address %s\n",
3079 				    fd, stoa(addr)));
3080 	}
3081 #endif
3082 #ifdef HAVE_BINTIME
3083 	{
3084 		if (setsockopt(fd, SOL_SOCKET, SO_BINTIME,
3085 			       (void *)&on, sizeof(on)))
3086 			msyslog(LOG_DEBUG,
3087 				"setsockopt SO_BINTIME on fails on address %s: %m",
3088 				stoa(addr));
3089 		else
3090 			DPRINTF(4, ("setsockopt SO_BINTIME enabled on fd %d address %s\n",
3091 				    fd, stoa(addr)));
3092 	}
3093 #endif
3094 
3095 	DPRINTF(4, ("bind(%d) AF_INET%s, addr %s%%%d#%d, flags 0x%x\n",
3096 		   fd, IS_IPV6(addr) ? "6" : "", stoa(addr),
3097 		   SCOPE(addr), SRCPORT(addr), interf->flags));
3098 
3099 	make_socket_nonblocking(fd);
3100 
3101 #ifdef HAVE_SIGNALED_IO
3102 	init_socket_sig(fd);
3103 #endif /* not HAVE_SIGNALED_IO */
3104 
3105 	add_fd_to_list(fd, FD_TYPE_SOCKET);
3106 
3107 #if !defined(SYS_WINNT) && !defined(VMS)
3108 	DPRINTF(4, ("flags for fd %d: 0x%x\n", fd,
3109 		    fcntl(fd, F_GETFL, 0)));
3110 #endif /* SYS_WINNT || VMS */
3111 
3112 #if defined(HAVE_IO_COMPLETION_PORT)
3113 /*
3114  * Add the socket to the completion port
3115  */
3116 	if (!io_completion_port_add_socket(fd, interf, bcast)) {
3117 		msyslog(LOG_ERR, "unable to set up io completion port - EXITING");
3118 		exit(1);
3119 	}
3120 #endif
3121 	return fd;
3122 }
3123 
3124 
3125 
3126 /* XXX ELIMINATE sendpkt similar in ntpq.c, ntpdc.c, ntp_io.c, ntptrace.c */
3127 /*
3128  * sendpkt - send a packet to the specified destination. Maintain a
3129  * send error cache so that only the first consecutive error for a
3130  * destination is logged.
3131  */
3132 void
3133 sendpkt(
3134 	sockaddr_u *		dest,
3135 	struct interface *	ep,
3136 	int			ttl,
3137 	struct pkt *		pkt,
3138 	int			len
3139 	)
3140 {
3141 	endpt *	src;
3142 	int	ismcast;
3143 	int	cc;
3144 	int	rc;
3145 	u_char	cttl;
3146 	l_fp	fp_zero = { { 0 }, 0 };
3147 	l_fp	org, rec, xmt;
3148 
3149 	ismcast = IS_MCAST(dest);
3150 	if (!ismcast)
3151 		src = ep;
3152 	else
3153 		src = (IS_IPV4(dest))
3154 			  ? mc4_list
3155 			  : mc6_list;
3156 
3157 	if (NULL == src) {
3158 		/*
3159 		 * unbound peer - drop request and wait for better
3160 		 * network conditions
3161 		 */
3162 		DPRINTF(2, ("%ssendpkt(dst=%s, ttl=%d, len=%d): no interface - IGNORED\n",
3163 			    ismcast ? "\tMCAST\t***** " : "",
3164 			    stoa(dest), ttl, len));
3165 		return;
3166 	}
3167 
3168 	do {
3169 		DPRINTF(2, ("%ssendpkt(%d, dst=%s, src=%s, ttl=%d, len=%d)\n",
3170 			    ismcast ? "\tMCAST\t***** " : "", src->fd,
3171 			    stoa(dest), stoa(&src->sin), ttl, len));
3172 #ifdef MCAST
3173 		/*
3174 		 * for the moment we use the bcast option to set multicast ttl
3175 		 */
3176 		if (ismcast && ttl > 0 && ttl != src->last_ttl) {
3177 			/*
3178 			 * set the multicast ttl for outgoing packets
3179 			 */
3180 			switch (AF(&src->sin)) {
3181 
3182 			case AF_INET :
3183 				cttl = (u_char)ttl;
3184 				rc = setsockopt(src->fd, IPPROTO_IP,
3185 						IP_MULTICAST_TTL,
3186 						(void *)&cttl,
3187 						sizeof(cttl));
3188 				break;
3189 
3190 # ifdef INCLUDE_IPV6_SUPPORT
3191 			case AF_INET6 :
3192 				rc = setsockopt(src->fd, IPPROTO_IPV6,
3193 						 IPV6_MULTICAST_HOPS,
3194 						 (void *)&ttl,
3195 						 sizeof(ttl));
3196 				break;
3197 # endif	/* INCLUDE_IPV6_SUPPORT */
3198 
3199 			default:
3200 				rc = 0;
3201 			}
3202 
3203 			if (!rc)
3204 				src->last_ttl = ttl;
3205 			else
3206 				msyslog(LOG_ERR,
3207 					"setsockopt IP_MULTICAST_TTL/IPV6_MULTICAST_HOPS fails on address %s: %m",
3208 					stoa(&src->sin));
3209 		}
3210 #endif	/* MCAST */
3211 
3212 #ifdef SIM
3213 		cc = simulate_server(dest, src, pkt);
3214 #elif defined(HAVE_IO_COMPLETION_PORT)
3215 		cc = io_completion_port_sendto(src, src->fd, pkt,
3216 			(size_t)len, (sockaddr_u *)&dest->sa);
3217 #else
3218 		cc = sendto(src->fd, (char *)pkt, (u_int)len, 0,
3219 			    &dest->sa, SOCKLEN(dest));
3220 #endif
3221 		if (cc == -1) {
3222 			src->notsent++;
3223 			packets_notsent++;
3224 		} else	{
3225 			src->sent++;
3226 			packets_sent++;
3227 		}
3228 		if (ismcast)
3229 			src = src->mclink;
3230 	} while (ismcast && src != NULL);
3231 
3232 	/* HMS: pkt->rootdisp is usually random here */
3233 	NTOHL_FP(&pkt->org, &org);
3234 	NTOHL_FP(&pkt->rec, &rec);
3235 	NTOHL_FP(&pkt->xmt, &xmt);
3236 	record_raw_stats(src ? &src->sin : NULL, dest,
3237 			&org, &rec, &xmt, &fp_zero,
3238 			PKT_LEAP(pkt->li_vn_mode),
3239 			PKT_VERSION(pkt->li_vn_mode),
3240 			PKT_MODE(pkt->li_vn_mode),
3241 			pkt->stratum,
3242 			pkt->ppoll, pkt->precision,
3243 			pkt->rootdelay, pkt->rootdisp, pkt->refid,
3244 			len - MIN_V4_PKT_LEN, (u_char *)&pkt->exten);
3245 
3246 	return;
3247 }
3248 
3249 
3250 #if !defined(HAVE_IO_COMPLETION_PORT)
3251 #if !defined(HAVE_SIGNALED_IO)
3252 /*
3253  * fdbits - generate ascii representation of fd_set (FAU debug support)
3254  * HFDF format - highest fd first.
3255  */
3256 static char *
3257 fdbits(
3258 	int		count,
3259 	const fd_set*	set
3260 	)
3261 {
3262 	static char buffer[256];
3263 	char * buf = buffer;
3264 
3265 	count = min(count,  255);
3266 
3267 	while (count >= 0) {
3268 		*buf++ = FD_ISSET(count, set) ? '#' : '-';
3269 		count--;
3270 	}
3271 	*buf = '\0';
3272 
3273 	return buffer;
3274 }
3275 #endif
3276 
3277 #ifdef REFCLOCK
3278 /*
3279  * Routine to read the refclock packets for a specific interface
3280  * Return the number of bytes read. That way we know if we should
3281  * read it again or go on to the next one if no bytes returned
3282  */
3283 static inline int
3284 read_refclock_packet(
3285 	SOCKET			fd,
3286 	struct refclockio *	rp,
3287 	l_fp			ts
3288 	)
3289 {
3290 	u_int			read_count;
3291 	int			buflen;
3292 	int			saved_errno;
3293 	int			consumed;
3294 	struct recvbuf *	rb;
3295 
3296 	rb = get_free_recv_buffer(TRUE);
3297 
3298 	if (NULL == rb) {
3299 		/*
3300 		 * No buffer space available - just drop the 'packet'.
3301 		 * Since this is a non-blocking character stream we read
3302 		 * all data that we can.
3303 		 *
3304 		 * ...hmmmm... what about "tcflush(fd,TCIFLUSH)" here?!?
3305 		 */
3306 		char buf[128];
3307 		do
3308 			buflen = read(fd, buf, sizeof(buf));
3309 		while (buflen > 0);
3310 		packets_dropped++;
3311 		return (buflen);
3312 	}
3313 
3314 	/* TALOS-CAN-0064: avoid signed/unsigned clashes that can lead
3315 	 * to buffer overrun and memory corruption
3316 	 */
3317 	if (rp->datalen <= 0 || (size_t)rp->datalen > sizeof(rb->recv_space))
3318 		read_count = sizeof(rb->recv_space);
3319 	else
3320 		read_count = (u_int)rp->datalen;
3321 	do {
3322 		buflen = read(fd, (char *)&rb->recv_space, read_count);
3323 	} while (buflen < 0 && EINTR == errno);
3324 
3325 	if (buflen <= 0) {
3326 		saved_errno = errno;
3327 		freerecvbuf(rb);
3328 		errno = saved_errno;
3329 		return buflen;
3330 	}
3331 
3332 	/*
3333 	 * Got one. Mark how and when it got here,
3334 	 * put it on the full list and do bookkeeping.
3335 	 */
3336 	rb->recv_length = buflen;
3337 	rb->recv_peer = rp->srcclock;
3338 	rb->dstadr = 0;
3339 	rb->fd = fd;
3340 	rb->recv_time = ts;
3341 	rb->receiver = rp->clock_recv;
3342 
3343 	consumed = indicate_refclock_packet(rp, rb);
3344 	if (!consumed) {
3345 		rp->recvcount++;
3346 		packets_received++;
3347 	}
3348 
3349 	return buflen;
3350 }
3351 #endif	/* REFCLOCK */
3352 
3353 
3354 #ifdef HAVE_PACKET_TIMESTAMP
3355 /*
3356  * extract timestamps from control message buffer
3357  */
3358 static l_fp
3359 fetch_timestamp(
3360 	struct recvbuf *	rb,
3361 	struct msghdr *		msghdr,
3362 	l_fp			ts
3363 	)
3364 {
3365 	struct cmsghdr *	cmsghdr;
3366 	unsigned long		ticks;
3367 	double			fuzz;
3368 	l_fp			lfpfuzz;
3369 	l_fp			nts;
3370 #ifdef DEBUG_TIMING
3371 	l_fp			dts;
3372 #endif
3373 
3374 	cmsghdr = CMSG_FIRSTHDR(msghdr);
3375 	while (cmsghdr != NULL) {
3376 		switch (cmsghdr->cmsg_type)
3377 		{
3378 #ifdef HAVE_BINTIME
3379 		case SCM_BINTIME:
3380 #endif  /* HAVE_BINTIME */
3381 #ifdef HAVE_TIMESTAMPNS
3382 		case SCM_TIMESTAMPNS:
3383 #endif	/* HAVE_TIMESTAMPNS */
3384 #ifdef HAVE_TIMESTAMP
3385 		case SCM_TIMESTAMP:
3386 #endif	/* HAVE_TIMESTAMP */
3387 #if defined(HAVE_BINTIME) || defined (HAVE_TIMESTAMPNS) || defined(HAVE_TIMESTAMP)
3388 			switch (cmsghdr->cmsg_type)
3389 			{
3390 #ifdef HAVE_BINTIME
3391 			case SCM_BINTIME:
3392 				{
3393 					struct bintime	pbt;
3394 					memcpy(&pbt, CMSG_DATA(cmsghdr), sizeof(pbt));
3395 					/*
3396 					 * bintime documentation is at http://phk.freebsd.dk/pubs/timecounter.pdf
3397 					 */
3398 					nts.l_i = pbt.sec + JAN_1970;
3399 					nts.l_uf = (u_int32)(pbt.frac >> 32);
3400 					if (sys_tick > measured_tick &&
3401 					    sys_tick > 1e-9) {
3402 						ticks = (unsigned long)(nts.l_uf / (unsigned long)(sys_tick * FRAC));
3403 						nts.l_uf = (unsigned long)(ticks * (unsigned long)(sys_tick * FRAC));
3404 					}
3405 					DPRINTF(4, ("fetch_timestamp: system bintime network time stamp: %ld.%09lu\n",
3406 						    pbt.sec, (unsigned long)((nts.l_uf / FRAC) * 1e9)));
3407 				}
3408 				break;
3409 #endif  /* HAVE_BINTIME */
3410 #ifdef HAVE_TIMESTAMPNS
3411 			case SCM_TIMESTAMPNS:
3412 				{
3413 					struct timespec	pts;
3414 					memcpy(&pts, CMSG_DATA(cmsghdr), sizeof(pts));
3415 					if (sys_tick > measured_tick &&
3416 					    sys_tick > 1e-9) {
3417 						ticks = (unsigned long)((pts.tv_nsec * 1e-9) /
3418 									sys_tick);
3419 						pts.tv_nsec = (long)(ticks * 1e9 *
3420 								     sys_tick);
3421 					}
3422 					DPRINTF(4, ("fetch_timestamp: system nsec network time stamp: %ld.%09ld\n",
3423 						    pts.tv_sec, pts.tv_nsec));
3424 					nts = tspec_stamp_to_lfp(pts);
3425 				}
3426 				break;
3427 #endif	/* HAVE_TIMESTAMPNS */
3428 #ifdef HAVE_TIMESTAMP
3429 			case SCM_TIMESTAMP:
3430 				{
3431 					struct timeval	ptv;
3432 					memcpy(&ptv, CMSG_DATA(cmsghdr), sizeof(ptv));
3433 					if (sys_tick > measured_tick &&
3434 					    sys_tick > 1e-6) {
3435 						ticks = (unsigned long)((ptv.tv_usec * 1e-6) /
3436 									sys_tick);
3437 						ptv.tv_usec = (long)(ticks * 1e6 *
3438 								    sys_tick);
3439 					}
3440 					DPRINTF(4, ("fetch_timestamp: system usec network time stamp: %jd.%06ld\n",
3441 						    (intmax_t)ptv.tv_sec, (long)ptv.tv_usec));
3442 					nts = tval_stamp_to_lfp(ptv);
3443 				}
3444 				break;
3445 #endif  /* HAVE_TIMESTAMP */
3446 			}
3447 			fuzz = ntp_random() * 2. / FRAC * sys_fuzz;
3448 			DTOLFP(fuzz, &lfpfuzz);
3449 			L_ADD(&nts, &lfpfuzz);
3450 #ifdef DEBUG_TIMING
3451 			dts = ts;
3452 			L_SUB(&dts, &nts);
3453 			collect_timing(rb, "input processing delay", 1,
3454 				       &dts);
3455 			DPRINTF(4, ("fetch_timestamp: timestamp delta: %s (incl. fuzz)\n",
3456 				    lfptoa(&dts, 9)));
3457 #endif	/* DEBUG_TIMING */
3458 			ts = nts;  /* network time stamp */
3459 			break;
3460 #endif	/* HAVE_BINTIME || HAVE_TIMESTAMPNS || HAVE_TIMESTAMP */
3461 
3462 		default:
3463 			DPRINTF(4, ("fetch_timestamp: skipping control message 0x%x\n",
3464 				    cmsghdr->cmsg_type));
3465 		}
3466 		cmsghdr = CMSG_NXTHDR(msghdr, cmsghdr);
3467 	}
3468 	return ts;
3469 }
3470 #endif	/* HAVE_PACKET_TIMESTAMP */
3471 
3472 
3473 /*
3474  * Routine to read the network NTP packets for a specific interface
3475  * Return the number of bytes read. That way we know if we should
3476  * read it again or go on to the next one if no bytes returned
3477  */
3478 static inline int
3479 read_network_packet(
3480 	SOCKET			fd,
3481 	struct interface *	itf,
3482 	l_fp			ts
3483 	)
3484 {
3485 	GETSOCKNAME_SOCKLEN_TYPE fromlen;
3486 	int buflen;
3487 	register struct recvbuf *rb;
3488 #ifdef HAVE_PACKET_TIMESTAMP
3489 	struct msghdr msghdr;
3490 	struct iovec iovec;
3491 	char control[CMSG_BUFSIZE];
3492 #endif
3493 
3494 	/*
3495 	 * Get a buffer and read the frame.  If we haven't got a buffer,
3496 	 * or this is received on a disallowed socket, just dump the
3497 	 * packet.
3498 	 */
3499 
3500 	rb = itf->ignore_packets ? NULL : get_free_recv_buffer(FALSE);
3501 	if (NULL == rb) {
3502 		/* A partial read on a UDP socket truncates the data and
3503 		 * removes the message from the queue. So there's no
3504 		 * need to have a full buffer here on the stack.
3505 		 */
3506 		char buf[16];
3507 		sockaddr_u from;
3508 
3509 		if (rb != NULL)
3510 			freerecvbuf(rb);
3511 
3512 		fromlen = sizeof(from);
3513 		buflen = recvfrom(fd, buf, sizeof(buf), 0,
3514 				  &from.sa, &fromlen);
3515 		DPRINTF(4, ("%s on (%lu) fd=%d from %s\n",
3516 			(itf->ignore_packets)
3517 			    ? "ignore"
3518 			    : "drop",
3519 			free_recvbuffs(), fd, stoa(&from)));
3520 		if (itf->ignore_packets)
3521 			packets_ignored++;
3522 		else
3523 			packets_dropped++;
3524 		return (buflen);
3525 	}
3526 
3527 	fromlen = sizeof(rb->recv_srcadr);
3528 
3529 #ifndef HAVE_PACKET_TIMESTAMP
3530 	rb->recv_length = recvfrom(fd, (char *)&rb->recv_space,
3531 				   sizeof(rb->recv_space), 0,
3532 				   &rb->recv_srcadr.sa, &fromlen);
3533 #else
3534 	iovec.iov_base        = &rb->recv_space;
3535 	iovec.iov_len         = sizeof(rb->recv_space);
3536 	msghdr.msg_name       = &rb->recv_srcadr;
3537 	msghdr.msg_namelen    = fromlen;
3538 	msghdr.msg_iov        = &iovec;
3539 	msghdr.msg_iovlen     = 1;
3540 	msghdr.msg_control    = (void *)&control;
3541 	msghdr.msg_controllen = sizeof(control);
3542 	msghdr.msg_flags      = 0;
3543 	rb->recv_length       = recvmsg(fd, &msghdr, 0);
3544 #endif
3545 
3546 	buflen = rb->recv_length;
3547 
3548 	if (buflen == 0 || (buflen == -1 &&
3549 	    (EWOULDBLOCK == errno
3550 #ifdef EAGAIN
3551 	     || EAGAIN == errno
3552 #endif
3553 	     ))) {
3554 		freerecvbuf(rb);
3555 		return (buflen);
3556 	} else if (buflen < 0) {
3557 		msyslog(LOG_ERR, "recvfrom(%s) fd=%d: %m",
3558 			stoa(&rb->recv_srcadr), fd);
3559 		DPRINTF(5, ("read_network_packet: fd=%d dropped (bad recvfrom)\n",
3560 			    fd));
3561 		freerecvbuf(rb);
3562 		return (buflen);
3563 	}
3564 
3565 	DPRINTF(3, ("read_network_packet: fd=%d length %d from %s\n",
3566 		    fd, buflen, stoa(&rb->recv_srcadr)));
3567 
3568 #ifdef ENABLE_BUG3020_FIX
3569 	if (ISREFCLOCKADR(&rb->recv_srcadr)) {
3570 		msyslog(LOG_ERR, "recvfrom(%s) fd=%d: refclock srcadr on a network interface!",
3571 			stoa(&rb->recv_srcadr), fd);
3572 		DPRINTF(1, ("read_network_packet: fd=%d dropped (refclock srcadr))\n",
3573 			    fd));
3574 		packets_dropped++;
3575 		freerecvbuf(rb);
3576 		return (buflen);
3577 	}
3578 #endif
3579 
3580 	/*
3581 	** Bug 2672: Some OSes (MacOSX and Linux) don't block spoofed ::1
3582 	*/
3583 
3584 	if (AF_INET6 == itf->family) {
3585 		DPRINTF(2, ("Got an IPv6 packet, from <%s> (%d) to <%s> (%d)\n",
3586 			stoa(&rb->recv_srcadr),
3587 			IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&rb->recv_srcadr)),
3588 			stoa(&itf->sin),
3589 			!IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&itf->sin))
3590 			));
3591 
3592 		if (   IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&rb->recv_srcadr))
3593 		    && !IN6_IS_ADDR_LOOPBACK(PSOCK_ADDR6(&itf->sin))
3594 		   ) {
3595 			packets_dropped++;
3596 			DPRINTF(2, ("DROPPING that packet\n"));
3597 			freerecvbuf(rb);
3598 			return buflen;
3599 		}
3600 		DPRINTF(2, ("processing that packet\n"));
3601 	}
3602 
3603 	/*
3604 	 * Got one.  Mark how and when it got here,
3605 	 * put it on the full list and do bookkeeping.
3606 	 */
3607 	rb->dstadr = itf;
3608 	rb->fd = fd;
3609 #ifdef HAVE_PACKET_TIMESTAMP
3610 	/* pick up a network time stamp if possible */
3611 	ts = fetch_timestamp(rb, &msghdr, ts);
3612 #endif
3613 	rb->recv_time = ts;
3614 	rb->receiver = receive;
3615 
3616 	add_full_recv_buffer(rb);
3617 
3618 	itf->received++;
3619 	packets_received++;
3620 	return (buflen);
3621 }
3622 
3623 /*
3624  * attempt to handle io (select()/signaled IO)
3625  */
3626 void
3627 io_handler(void)
3628 {
3629 #  ifndef HAVE_SIGNALED_IO
3630 	fd_set rdfdes;
3631 	int nfound;
3632 
3633 	/*
3634 	 * Use select() on all on all input fd's for unlimited
3635 	 * time.  select() will terminate on SIGALARM or on the
3636 	 * reception of input.	Using select() means we can't do
3637 	 * robust signal handling and we get a potential race
3638 	 * between checking for alarms and doing the select().
3639 	 * Mostly harmless, I think.
3640 	 */
3641 	/*
3642 	 * On VMS, I suspect that select() can't be interrupted
3643 	 * by a "signal" either, so I take the easy way out and
3644 	 * have select() time out after one second.
3645 	 * System clock updates really aren't time-critical,
3646 	 * and - lacking a hardware reference clock - I have
3647 	 * yet to learn about anything else that is.
3648 	 */
3649 	++handler_calls;
3650 	rdfdes = activefds;
3651 #   if !defined(VMS) && !defined(SYS_VXWORKS)
3652 	nfound = select(maxactivefd + 1, &rdfdes, NULL,
3653 			NULL, NULL);
3654 #   else	/* VMS, VxWorks */
3655 	/* make select() wake up after one second */
3656 	{
3657 		struct timeval t1;
3658 		t1.tv_sec  = 1;
3659 		t1.tv_usec = 0;
3660 		nfound = select(maxactivefd + 1,
3661 				&rdfdes, NULL, NULL,
3662 				&t1);
3663 	}
3664 #   endif	/* VMS, VxWorks */
3665 	if (nfound < 0 && sanitize_fdset(errno)) {
3666 		struct timeval t1;
3667 		t1.tv_sec  = 0;
3668 		t1.tv_usec = 0;
3669 		rdfdes = activefds;
3670 		nfound = select(maxactivefd + 1,
3671 				&rdfdes, NULL, NULL,
3672 				&t1);
3673 	}
3674 
3675 	if (nfound > 0) {
3676 		l_fp ts;
3677 
3678 		get_systime(&ts);
3679 
3680 		input_handler_scan(&ts, &rdfdes);
3681 	} else if (nfound == -1 && errno != EINTR) {
3682 		msyslog(LOG_ERR, "select() error: %m");
3683 	}
3684 #   ifdef DEBUG
3685 	else if (debug > 4) {
3686 		msyslog(LOG_DEBUG, "select(): nfound=%d, error: %m", nfound);
3687 	} else {
3688 		DPRINTF(3, ("select() returned %d: %m\n", nfound));
3689 	}
3690 #   endif /* DEBUG */
3691 #  else /* HAVE_SIGNALED_IO */
3692 	wait_for_signal();
3693 #  endif /* HAVE_SIGNALED_IO */
3694 }
3695 
3696 #ifdef HAVE_SIGNALED_IO
3697 /*
3698  * input_handler - receive packets asynchronously
3699  *
3700  * ALWAYS IN SIGNAL HANDLER CONTEXT -- only async-safe functions allowed!
3701  */
3702 static RETSIGTYPE
3703 input_handler(
3704 	l_fp *	cts
3705 	)
3706 {
3707 	int		n;
3708 	struct timeval	tvzero;
3709 	fd_set		fds;
3710 
3711 	++handler_calls;
3712 
3713 	/*
3714 	 * Do a poll to see who has data
3715 	 */
3716 
3717 	fds = activefds;
3718 	tvzero.tv_sec = tvzero.tv_usec = 0;
3719 
3720 	n = select(maxactivefd + 1, &fds, NULL, NULL, &tvzero);
3721 	if (n < 0 && sanitize_fdset(errno)) {
3722 		fds = activefds;
3723 		tvzero.tv_sec = tvzero.tv_usec = 0;
3724 		n = select(maxactivefd + 1, &fds, NULL, NULL, &tvzero);
3725 	}
3726 	if (n > 0)
3727 		input_handler_scan(cts, &fds);
3728 }
3729 #endif /* HAVE_SIGNALED_IO */
3730 
3731 
3732 /*
3733  * Try to sanitize the global FD set
3734  *
3735  * SIGNAL HANDLER CONTEXT if HAVE_SIGNALED_IO, ordinary userspace otherwise
3736  */
3737 static int/*BOOL*/
3738 sanitize_fdset(
3739 	int	errc
3740 	)
3741 {
3742 	int j, b, maxscan;
3743 
3744 #  ifndef HAVE_SIGNALED_IO
3745 	/*
3746 	 * extended FAU debugging output
3747 	 */
3748 	if (errc != EINTR) {
3749 		msyslog(LOG_ERR,
3750 			"select(%d, %s, 0L, 0L, &0.0) error: %m",
3751 			maxactivefd + 1,
3752 			fdbits(maxactivefd, &activefds));
3753 	}
3754 #   endif
3755 
3756 	if (errc != EBADF)
3757 		return FALSE;
3758 
3759 	/* if we have oviously bad FDs, try to sanitize the FD set. */
3760 	for (j = 0, maxscan = 0; j <= maxactivefd; j++) {
3761 		if (FD_ISSET(j, &activefds)) {
3762 			if (-1 != read(j, &b, 0)) {
3763 				maxscan = j;
3764 				continue;
3765 			}
3766 #		    ifndef HAVE_SIGNALED_IO
3767 			msyslog(LOG_ERR,
3768 				"Removing bad file descriptor %d from select set",
3769 				j);
3770 #		    endif
3771 			FD_CLR(j, &activefds);
3772 		}
3773 	}
3774 	if (maxactivefd != maxscan)
3775 		maxactivefd = maxscan;
3776 	return TRUE;
3777 }
3778 
3779 /*
3780  * scan the known FDs (clocks, servers, ...) for presence in a 'fd_set'.
3781  *
3782  * SIGNAL HANDLER CONTEXT if HAVE_SIGNALED_IO, ordinary userspace otherwise
3783  */
3784 static void
3785 input_handler_scan(
3786 	const l_fp *	cts,
3787 	const fd_set *	pfds
3788 	)
3789 {
3790 	int		buflen;
3791 	u_int		idx;
3792 	int		doing;
3793 	SOCKET		fd;
3794 	blocking_child *c;
3795 	l_fp		ts;	/* Timestamp at BOselect() gob */
3796 
3797 #if defined(DEBUG_TIMING)
3798 	l_fp		ts_e;	/* Timestamp at EOselect() gob */
3799 #endif
3800 	endpt *		ep;
3801 #ifdef REFCLOCK
3802 	struct refclockio *rp;
3803 	int		saved_errno;
3804 	const char *	clk;
3805 #endif
3806 #ifdef HAS_ROUTING_SOCKET
3807 	struct asyncio_reader *	asyncio_reader;
3808 	struct asyncio_reader *	next_asyncio_reader;
3809 #endif
3810 
3811 	++handler_pkts;
3812 	ts = *cts;
3813 
3814 #ifdef REFCLOCK
3815 	/*
3816 	 * Check out the reference clocks first, if any
3817 	 */
3818 
3819 	for (rp = refio; rp != NULL; rp = rp->next) {
3820 		fd = rp->fd;
3821 
3822 		if (!FD_ISSET(fd, pfds))
3823 			continue;
3824 		buflen = read_refclock_packet(fd, rp, ts);
3825 		/*
3826 		 * The first read must succeed after select() indicates
3827 		 * readability, or we've reached a permanent EOF.
3828 		 * http://bugs.ntp.org/1732 reported ntpd munching CPU
3829 		 * after a USB GPS was unplugged because select was
3830 		 * indicating EOF but ntpd didn't remove the descriptor
3831 		 * from the activefds set.
3832 		 */
3833 		if (buflen < 0 && EAGAIN != errno) {
3834 			saved_errno = errno;
3835 			clk = refnumtoa(&rp->srcclock->srcadr);
3836 			errno = saved_errno;
3837 			msyslog(LOG_ERR, "%s read: %m", clk);
3838 			maintain_activefds(fd, TRUE);
3839 		} else if (0 == buflen) {
3840 			clk = refnumtoa(&rp->srcclock->srcadr);
3841 			msyslog(LOG_ERR, "%s read EOF", clk);
3842 			maintain_activefds(fd, TRUE);
3843 		} else {
3844 			/* drain any remaining refclock input */
3845 			do {
3846 				buflen = read_refclock_packet(fd, rp, ts);
3847 			} while (buflen > 0);
3848 		}
3849 	}
3850 #endif /* REFCLOCK */
3851 
3852 	/*
3853 	 * Loop through the interfaces looking for data to read.
3854 	 */
3855 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
3856 		for (doing = 0; doing < 2; doing++) {
3857 			if (!doing) {
3858 				fd = ep->fd;
3859 			} else {
3860 				if (!(ep->flags & INT_BCASTOPEN))
3861 					break;
3862 				fd = ep->bfd;
3863 			}
3864 			if (fd < 0)
3865 				continue;
3866 			if (FD_ISSET(fd, pfds))
3867 				do {
3868 					buflen = read_network_packet(
3869 							fd, ep, ts);
3870 				} while (buflen > 0);
3871 			/* Check more interfaces */
3872 		}
3873 	}
3874 
3875 #ifdef HAS_ROUTING_SOCKET
3876 	/*
3877 	 * scan list of asyncio readers - currently only used for routing sockets
3878 	 */
3879 	asyncio_reader = asyncio_reader_list;
3880 
3881 	while (asyncio_reader != NULL) {
3882 		/* callback may unlink and free asyncio_reader */
3883 		next_asyncio_reader = asyncio_reader->link;
3884 		if (FD_ISSET(asyncio_reader->fd, pfds))
3885 			(*asyncio_reader->receiver)(asyncio_reader);
3886 		asyncio_reader = next_asyncio_reader;
3887 	}
3888 #endif /* HAS_ROUTING_SOCKET */
3889 
3890 	/*
3891 	 * Check for a response from a blocking child
3892 	 */
3893 	for (idx = 0; idx < blocking_children_alloc; idx++) {
3894 		c = blocking_children[idx];
3895 		if (NULL == c || -1 == c->resp_read_pipe)
3896 			continue;
3897 		if (FD_ISSET(c->resp_read_pipe, pfds)) {
3898 			++c->resp_ready_seen;
3899 			++blocking_child_ready_seen;
3900 		}
3901 	}
3902 
3903 	/* We've done our work */
3904 #if defined(DEBUG_TIMING)
3905 	get_systime(&ts_e);
3906 	/*
3907 	 * (ts_e - ts) is the amount of time we spent
3908 	 * processing this gob of file descriptors.  Log
3909 	 * it.
3910 	 */
3911 	L_SUB(&ts_e, &ts);
3912 	collect_timing(NULL, "input handler", 1, &ts_e);
3913 	if (debug > 3)
3914 		msyslog(LOG_DEBUG,
3915 			"input_handler: Processed a gob of fd's in %s msec",
3916 			lfptoms(&ts_e, 6));
3917 #endif /* DEBUG_TIMING */
3918 }
3919 #endif /* !HAVE_IO_COMPLETION_PORT */
3920 
3921 /*
3922  * find an interface suitable for the src address
3923  */
3924 endpt *
3925 select_peerinterface(
3926 	struct peer *	peer,
3927 	sockaddr_u *	srcadr,
3928 	endpt *		dstadr
3929 	)
3930 {
3931 	endpt *ep;
3932 #ifndef SIM
3933 	endpt *wild;
3934 
3935 	wild = ANY_INTERFACE_CHOOSE(srcadr);
3936 
3937 	/*
3938 	 * Initialize the peer structure and dance the interface jig.
3939 	 * Reference clocks step the loopback waltz, the others
3940 	 * squaredance around the interface list looking for a buddy. If
3941 	 * the dance peters out, there is always the wildcard interface.
3942 	 * This might happen in some systems and would preclude proper
3943 	 * operation with public key cryptography.
3944 	 */
3945 	if (ISREFCLOCKADR(srcadr)) {
3946 		ep = loopback_interface;
3947 	} else if (peer->cast_flags &
3948 		   (MDF_BCLNT | MDF_ACAST | MDF_MCAST | MDF_BCAST)) {
3949 		ep = findbcastinter(srcadr);
3950 		if (ep != NULL)
3951 			DPRINTF(4, ("Found *-cast interface %s for address %s\n",
3952 				stoa(&ep->sin), stoa(srcadr)));
3953 		else
3954 			DPRINTF(4, ("No *-cast local address found for address %s\n",
3955 				stoa(srcadr)));
3956 	} else {
3957 		ep = dstadr;
3958 		if (NULL == ep)
3959 			ep = wild;
3960 	}
3961 	/*
3962 	 * If it is a multicast address, findbcastinter() may not find
3963 	 * it.  For unicast, we get to find the interface when dstadr is
3964 	 * given to us as the wildcard (ANY_INTERFACE_CHOOSE).  Either
3965 	 * way, try a little harder.
3966 	 */
3967 	if (wild == ep)
3968 		ep = findinterface(srcadr);
3969 	/*
3970 	 * we do not bind to the wildcard interfaces for output
3971 	 * as our (network) source address would be undefined and
3972 	 * crypto will not work without knowing the own transmit address
3973 	 */
3974 	if (ep != NULL && INT_WILDCARD & ep->flags)
3975 		if (!accept_wildcard_if_for_winnt)
3976 			ep = NULL;
3977 #else	/* SIM follows */
3978 	ep = loopback_interface;
3979 #endif
3980 
3981 	return ep;
3982 }
3983 
3984 
3985 /*
3986  * findinterface - find local interface corresponding to address
3987  */
3988 endpt *
3989 findinterface(
3990 	sockaddr_u *addr
3991 	)
3992 {
3993 	endpt *iface;
3994 
3995 	iface = findlocalinterface(addr, INT_WILDCARD, 0);
3996 
3997 	if (NULL == iface) {
3998 		DPRINTF(4, ("Found no interface for address %s - returning wildcard\n",
3999 			    stoa(addr)));
4000 
4001 		iface = ANY_INTERFACE_CHOOSE(addr);
4002 	} else
4003 		DPRINTF(4, ("Found interface #%d %s for address %s\n",
4004 			    iface->ifnum, iface->name, stoa(addr)));
4005 
4006 	return iface;
4007 }
4008 
4009 /*
4010  * findlocalinterface - find local interface corresponding to addr,
4011  * which does not have any of flags set.  If bast is nonzero, addr is
4012  * a broadcast address.
4013  *
4014  * This code attempts to find the local sending address for an outgoing
4015  * address by connecting a new socket to destinationaddress:NTP_PORT
4016  * and reading the sockname of the resulting connect.
4017  * the complicated sequence simulates the routing table lookup
4018  * for to first hop without duplicating any of the routing logic into
4019  * ntpd. preferably we would have used an API call - but its not there -
4020  * so this is the best we can do here short of duplicating to entire routing
4021  * logic in ntpd which would be a silly and really unportable thing to do.
4022  *
4023  */
4024 static endpt *
4025 findlocalinterface(
4026 	sockaddr_u *	addr,
4027 	int		flags,
4028 	int		bcast
4029 	)
4030 {
4031 	GETSOCKNAME_SOCKLEN_TYPE	sockaddrlen;
4032 	endpt *				iface;
4033 	sockaddr_u			saddr;
4034 	SOCKET				s;
4035 	int				rtn;
4036 	int				on;
4037 
4038 	DPRINTF(4, ("Finding interface for addr %s in list of addresses\n",
4039 		    stoa(addr)));
4040 
4041 	/* [Bug 3437] The dummy POOL peer comes in with an AF of
4042 	 * zero. This is bound to fail, but on the way to nowhere it
4043 	 * triggers a security incident on SELinux.
4044 	 *
4045 	 * Checking the condition and failing early is probably a good
4046 	 * advice, and even saves us some syscalls in that case.
4047 	 * Thanks to Miroslav Lichvar for finding this.
4048 	 */
4049 	if (AF_UNSPEC == AF(addr))
4050 		return NULL;
4051 
4052 	s = socket(AF(addr), SOCK_DGRAM, 0);
4053 	if (INVALID_SOCKET == s)
4054 		return NULL;
4055 
4056 	/*
4057 	 * If we are looking for broadcast interface we need to set this
4058 	 * socket to allow broadcast
4059 	 */
4060 	if (bcast) {
4061 		on = 1;
4062 		if (SOCKET_ERROR == setsockopt(s, SOL_SOCKET,
4063 						SO_BROADCAST,
4064 						(void *)&on,
4065 						sizeof(on))) {
4066 			closesocket(s);
4067 			return NULL;
4068 		}
4069 	}
4070 
4071 	rtn = connect(s, &addr->sa, SOCKLEN(addr));
4072 	if (SOCKET_ERROR == rtn) {
4073 		closesocket(s);
4074 		return NULL;
4075 	}
4076 
4077 	sockaddrlen = sizeof(saddr);
4078 	rtn = getsockname(s, &saddr.sa, &sockaddrlen);
4079 	closesocket(s);
4080 	if (SOCKET_ERROR == rtn)
4081 		return NULL;
4082 
4083 	DPRINTF(4, ("findlocalinterface: kernel maps %s to %s\n",
4084 		    stoa(addr), stoa(&saddr)));
4085 
4086 	iface = getinterface(&saddr, flags);
4087 
4088 	/*
4089 	 * if we didn't find an exact match on saddr, find the closest
4090 	 * available local address.  This handles the case of the
4091 	 * address suggested by the kernel being excluded by nic rules
4092 	 * or the user's -I and -L options to ntpd.
4093 	 * See http://bugs.ntp.org/1184 and http://bugs.ntp.org/1683
4094 	 * for more background.
4095 	 */
4096 	if (NULL == iface || iface->ignore_packets)
4097 		iface = findclosestinterface(&saddr,
4098 					     flags | INT_LOOPBACK);
4099 
4100 	/* Don't use an interface which will ignore replies */
4101 	if (iface != NULL && iface->ignore_packets)
4102 		iface = NULL;
4103 
4104 	return iface;
4105 }
4106 
4107 
4108 /*
4109  * findclosestinterface
4110  *
4111  * If there are -I/--interface or -L/novirtualips command-line options,
4112  * or "nic" or "interface" rules in ntp.conf, findlocalinterface() may
4113  * find the kernel's preferred local address for a given peer address is
4114  * administratively unavailable to ntpd, and punt to this routine's more
4115  * expensive search.
4116  *
4117  * Find the numerically closest local address to the one connect()
4118  * suggested.  This matches an address on the same subnet first, as
4119  * needed by Bug 1184, and provides a consistent choice if there are
4120  * multiple feasible local addresses, regardless of the order ntpd
4121  * enumerated them.
4122  */
4123 endpt *
4124 findclosestinterface(
4125 	sockaddr_u *	addr,
4126 	int		flags
4127 	)
4128 {
4129 	endpt *		ep;
4130 	endpt *		winner;
4131 	sockaddr_u	addr_dist;
4132 	sockaddr_u	min_dist;
4133 
4134 	ZERO_SOCK(&min_dist);
4135 	winner = NULL;
4136 
4137 	for (ep = ep_list; ep != NULL; ep = ep->elink) {
4138 		if (ep->ignore_packets ||
4139 		    AF(addr) != ep->family ||
4140 		    flags & ep->flags)
4141 			continue;
4142 
4143 		calc_addr_distance(&addr_dist, addr, &ep->sin);
4144 		if (NULL == winner ||
4145 		    -1 == cmp_addr_distance(&addr_dist, &min_dist)) {
4146 			min_dist = addr_dist;
4147 			winner = ep;
4148 		}
4149 	}
4150 	if (NULL == winner)
4151 		DPRINTF(4, ("findclosestinterface(%s) failed\n",
4152 			    stoa(addr)));
4153 	else
4154 		DPRINTF(4, ("findclosestinterface(%s) -> %s\n",
4155 			    stoa(addr), stoa(&winner->sin)));
4156 
4157 	return winner;
4158 }
4159 
4160 
4161 /*
4162  * calc_addr_distance - calculate the distance between two addresses,
4163  *			the absolute value of the difference between
4164  *			the addresses numerically, stored as an address.
4165  */
4166 static void
4167 calc_addr_distance(
4168 	sockaddr_u *		dist,
4169 	const sockaddr_u *	a1,
4170 	const sockaddr_u *	a2
4171 	)
4172 {
4173 	u_int32	a1val;
4174 	u_int32	a2val;
4175 	u_int32	v4dist;
4176 	int	found_greater;
4177 	int	a1_greater;
4178 	int	i;
4179 
4180 	REQUIRE(AF(a1) == AF(a2));
4181 
4182 	ZERO_SOCK(dist);
4183 	AF(dist) = AF(a1);
4184 
4185 	/* v4 can be done a bit simpler */
4186 	if (IS_IPV4(a1)) {
4187 		a1val = SRCADR(a1);
4188 		a2val = SRCADR(a2);
4189 		v4dist = (a1val > a2val)
4190 			     ? a1val - a2val
4191 			     : a2val - a1val;
4192 		SET_ADDR4(dist, v4dist);
4193 
4194 		return;
4195 	}
4196 
4197 	found_greater = FALSE;
4198 	a1_greater = FALSE;	/* suppress pot. uninit. warning */
4199 	for (i = 0; i < (int)sizeof(NSRCADR6(a1)); i++) {
4200 		if (!found_greater &&
4201 		    NSRCADR6(a1)[i] != NSRCADR6(a2)[i]) {
4202 			found_greater = TRUE;
4203 			a1_greater = (NSRCADR6(a1)[i] > NSRCADR6(a2)[i]);
4204 		}
4205 		if (!found_greater) {
4206 			NSRCADR6(dist)[i] = 0;
4207 		} else {
4208 			if (a1_greater)
4209 				NSRCADR6(dist)[i] = NSRCADR6(a1)[i] -
4210 						    NSRCADR6(a2)[i];
4211 			else
4212 				NSRCADR6(dist)[i] = NSRCADR6(a2)[i] -
4213 						    NSRCADR6(a1)[i];
4214 		}
4215 	}
4216 }
4217 
4218 
4219 /*
4220  * cmp_addr_distance - compare two address distances, returning -1, 0,
4221  *		       1 to indicate their relationship.
4222  */
4223 static int
4224 cmp_addr_distance(
4225 	const sockaddr_u *	d1,
4226 	const sockaddr_u *	d2
4227 	)
4228 {
4229 	int	i;
4230 
4231 	REQUIRE(AF(d1) == AF(d2));
4232 
4233 	if (IS_IPV4(d1)) {
4234 		if (SRCADR(d1) < SRCADR(d2))
4235 			return -1;
4236 		else if (SRCADR(d1) == SRCADR(d2))
4237 			return 0;
4238 		else
4239 			return 1;
4240 	}
4241 
4242 	for (i = 0; i < (int)sizeof(NSRCADR6(d1)); i++) {
4243 		if (NSRCADR6(d1)[i] < NSRCADR6(d2)[i])
4244 			return -1;
4245 		else if (NSRCADR6(d1)[i] > NSRCADR6(d2)[i])
4246 			return 1;
4247 	}
4248 
4249 	return 0;
4250 }
4251 
4252 
4253 
4254 /*
4255  * fetch an interface structure the matches the
4256  * address and has the given flags NOT set
4257  */
4258 endpt *
4259 getinterface(
4260 	sockaddr_u *	addr,
4261 	u_int32		flags
4262 	)
4263 {
4264 	endpt *iface;
4265 
4266 	iface = find_addr_in_list(addr);
4267 
4268 	if (iface != NULL && (iface->flags & flags))
4269 		iface = NULL;
4270 
4271 	return iface;
4272 }
4273 
4274 
4275 /*
4276  * findbcastinter - find broadcast interface corresponding to address
4277  */
4278 endpt *
4279 findbcastinter(
4280 	sockaddr_u *addr
4281 	)
4282 {
4283 	endpt *	iface;
4284 
4285 	iface = NULL;
4286 #if !defined(MPE) && (defined(SIOCGIFCONF) || defined(SYS_WINNT))
4287 	DPRINTF(4, ("Finding broadcast/multicast interface for addr %s in list of addresses\n",
4288 		    stoa(addr)));
4289 
4290 	iface = findlocalinterface(addr, INT_LOOPBACK | INT_WILDCARD,
4291 				   1);
4292 	if (iface != NULL) {
4293 		DPRINTF(4, ("Easily found bcast-/mcast- interface index #%d %s\n",
4294 			    iface->ifnum, iface->name));
4295 		return iface;
4296 	}
4297 
4298 	/*
4299 	 * plan B - try to find something reasonable in our lists in
4300 	 * case kernel lookup doesn't help
4301 	 */
4302 	for (iface = ep_list; iface != NULL; iface = iface->elink) {
4303 		if (iface->flags & INT_WILDCARD)
4304 			continue;
4305 
4306 		/* Don't bother with ignored interfaces */
4307 		if (iface->ignore_packets)
4308 			continue;
4309 
4310 		/*
4311 		 * First look if this is the correct family
4312 		 */
4313 		if(AF(&iface->sin) != AF(addr))
4314 			continue;
4315 
4316 		/* Skip the loopback addresses */
4317 		if (iface->flags & INT_LOOPBACK)
4318 			continue;
4319 
4320 		/*
4321 		 * If we are looking to match a multicast address and
4322 		 * this interface is one...
4323 		 */
4324 		if (addr_ismulticast(addr)
4325 		    && (iface->flags & INT_MULTICAST)) {
4326 #ifdef INCLUDE_IPV6_SUPPORT
4327 			/*
4328 			 * ...it is the winner unless we're looking for
4329 			 * an interface to use for link-local multicast
4330 			 * and its address is not link-local.
4331 			 */
4332 			if (IS_IPV6(addr)
4333 			    && IN6_IS_ADDR_MC_LINKLOCAL(PSOCK_ADDR6(addr))
4334 			    && !IN6_IS_ADDR_LINKLOCAL(PSOCK_ADDR6(&iface->sin)))
4335 				continue;
4336 #endif
4337 			break;
4338 		}
4339 
4340 		/*
4341 		 * We match only those interfaces marked as
4342 		 * broadcastable and either the explicit broadcast
4343 		 * address or the network portion of the IP address.
4344 		 * Sloppy.
4345 		 */
4346 		if (IS_IPV4(addr)) {
4347 			if (SOCK_EQ(&iface->bcast, addr))
4348 				break;
4349 
4350 			if ((NSRCADR(&iface->sin) & NSRCADR(&iface->mask))
4351 			    == (NSRCADR(addr)	  & NSRCADR(&iface->mask)))
4352 				break;
4353 		}
4354 #ifdef INCLUDE_IPV6_SUPPORT
4355 		else if (IS_IPV6(addr)) {
4356 			if (SOCK_EQ(&iface->bcast, addr))
4357 				break;
4358 
4359 			if (SOCK_EQ(netof(&iface->sin), netof(addr)))
4360 				break;
4361 		}
4362 #endif
4363 	}
4364 #endif /* SIOCGIFCONF */
4365 	if (NULL == iface) {
4366 		DPRINTF(4, ("No bcast interface found for %s\n",
4367 			    stoa(addr)));
4368 		iface = ANY_INTERFACE_CHOOSE(addr);
4369 	} else {
4370 		DPRINTF(4, ("Found bcast-/mcast- interface index #%d %s\n",
4371 			    iface->ifnum, iface->name));
4372 	}
4373 
4374 	return iface;
4375 }
4376 
4377 
4378 /*
4379  * io_clr_stats - clear I/O module statistics
4380  */
4381 void
4382 io_clr_stats(void)
4383 {
4384 	packets_dropped = 0;
4385 	packets_ignored = 0;
4386 	packets_received = 0;
4387 	packets_sent = 0;
4388 	packets_notsent = 0;
4389 
4390 	handler_calls = 0;
4391 	handler_pkts = 0;
4392 	io_timereset = current_time;
4393 }
4394 
4395 
4396 #ifdef REFCLOCK
4397 /*
4398  * io_addclock - add a reference clock to the list and arrange that we
4399  *				 get SIGIO interrupts from it.
4400  */
4401 int
4402 io_addclock(
4403 	struct refclockio *rio
4404 	)
4405 {
4406 	BLOCKIO();
4407 
4408 	/*
4409 	 * Stuff the I/O structure in the list and mark the descriptor
4410 	 * in use.  There is a harmless (I hope) race condition here.
4411 	 */
4412 	rio->active = TRUE;
4413 
4414 # ifdef HAVE_SIGNALED_IO
4415 	if (init_clock_sig(rio)) {
4416 		UNBLOCKIO();
4417 		return 0;
4418 	}
4419 # elif defined(HAVE_IO_COMPLETION_PORT)
4420 	if (!io_completion_port_add_clock_io(rio)) {
4421 		UNBLOCKIO();
4422 		return 0;
4423 	}
4424 # endif
4425 
4426 	/*
4427 	 * enqueue
4428 	 */
4429 	LINK_SLIST(refio, rio, next);
4430 
4431 	/*
4432 	 * register fd
4433 	 */
4434 	add_fd_to_list(rio->fd, FD_TYPE_FILE);
4435 
4436 	UNBLOCKIO();
4437 	return 1;
4438 }
4439 
4440 
4441 /*
4442  * io_closeclock - close the clock in the I/O structure given
4443  */
4444 void
4445 io_closeclock(
4446 	struct refclockio *rio
4447 	)
4448 {
4449 	struct refclockio *unlinked;
4450 
4451 	BLOCKIO();
4452 
4453 	/*
4454 	 * Remove structure from the list
4455 	 */
4456 	rio->active = FALSE;
4457 	UNLINK_SLIST(unlinked, refio, rio, next, struct refclockio);
4458 	if (NULL != unlinked) {
4459 		/* Close the descriptor. The order of operations is
4460 		 * important here in case of async / overlapped IO:
4461 		 * only after we have removed the clock from the
4462 		 * IO completion port we can be sure no further
4463 		 * input is queued. So...
4464 		 *  - we first disable feeding to the queu by removing
4465 		 *    the clock from the IO engine
4466 		 *  - close the file (which brings down any IO on it)
4467 		 *  - clear the buffer from results for this fd
4468 		 */
4469 #	    ifdef HAVE_IO_COMPLETION_PORT
4470 		io_completion_port_remove_clock_io(rio);
4471 #	    endif
4472 		close_and_delete_fd_from_list(rio->fd);
4473 		purge_recv_buffers_for_fd(rio->fd);
4474 		rio->fd = -1;
4475 	}
4476 
4477 	UNBLOCKIO();
4478 }
4479 #endif	/* REFCLOCK */
4480 
4481 
4482 /*
4483  * On NT a SOCKET is an unsigned int so we cannot possibly keep it in
4484  * an array. So we use one of the ISC_LIST functions to hold the
4485  * socket value and use that when we want to enumerate it.
4486  *
4487  * This routine is called by the forked intres child process to close
4488  * all open sockets.  On Windows there's no need as intres runs in
4489  * the same process as a thread.
4490  */
4491 #ifndef SYS_WINNT
4492 void
4493 kill_asyncio(
4494 	int	startfd
4495 	)
4496 {
4497 	BLOCKIO();
4498 
4499 	/*
4500 	 * In the child process we do not maintain activefds and
4501 	 * maxactivefd.  Zeroing maxactivefd disables code which
4502 	 * maintains it in close_and_delete_fd_from_list().
4503 	 */
4504 	maxactivefd = 0;
4505 
4506 	while (fd_list != NULL)
4507 		close_and_delete_fd_from_list(fd_list->fd);
4508 
4509 	UNBLOCKIO();
4510 }
4511 #endif	/* !SYS_WINNT */
4512 
4513 
4514 /*
4515  * Add and delete functions for the list of open sockets
4516  */
4517 static void
4518 add_fd_to_list(
4519 	SOCKET fd,
4520 	enum desc_type type
4521 	)
4522 {
4523 	vsock_t *lsock = emalloc(sizeof(*lsock));
4524 
4525 	lsock->fd = fd;
4526 	lsock->type = type;
4527 
4528 	LINK_SLIST(fd_list, lsock, link);
4529 	maintain_activefds(fd, 0);
4530 }
4531 
4532 
4533 static void
4534 close_and_delete_fd_from_list(
4535 	SOCKET fd
4536 	)
4537 {
4538 	vsock_t *lsock;
4539 
4540 	UNLINK_EXPR_SLIST(lsock, fd_list, fd ==
4541 	    UNLINK_EXPR_SLIST_CURRENT()->fd, link, vsock_t);
4542 
4543 	if (NULL == lsock)
4544 		return;
4545 
4546 	switch (lsock->type) {
4547 
4548 	case FD_TYPE_SOCKET:
4549 		closesocket(lsock->fd);
4550 		break;
4551 
4552 	case FD_TYPE_FILE:
4553 		closeserial((int)lsock->fd);
4554 		break;
4555 
4556 	default:
4557 		msyslog(LOG_ERR,
4558 			"internal error - illegal descriptor type %d - EXITING",
4559 			(int)lsock->type);
4560 		exit(1);
4561 	}
4562 
4563 	free(lsock);
4564 	/*
4565 	 * remove from activefds
4566 	 */
4567 	maintain_activefds(fd, 1);
4568 }
4569 
4570 
4571 static void
4572 add_addr_to_list(
4573 	sockaddr_u *	addr,
4574 	endpt *		ep
4575 	)
4576 {
4577 	remaddr_t *laddr;
4578 
4579 #ifdef DEBUG
4580 	if (find_addr_in_list(addr) == NULL) {
4581 #endif
4582 		/* not there yet - add to list */
4583 		laddr = emalloc(sizeof(*laddr));
4584 		laddr->addr = *addr;
4585 		laddr->ep = ep;
4586 
4587 		LINK_SLIST(remoteaddr_list, laddr, link);
4588 
4589 		DPRINTF(4, ("Added addr %s to list of addresses\n",
4590 			    stoa(addr)));
4591 #ifdef DEBUG
4592 	} else
4593 		DPRINTF(4, ("WARNING: Attempt to add duplicate addr %s to address list\n",
4594 			    stoa(addr)));
4595 #endif
4596 }
4597 
4598 
4599 static void
4600 delete_addr_from_list(
4601 	sockaddr_u *addr
4602 	)
4603 {
4604 	remaddr_t *unlinked;
4605 
4606 	UNLINK_EXPR_SLIST(unlinked, remoteaddr_list, SOCK_EQ(addr,
4607 		&(UNLINK_EXPR_SLIST_CURRENT()->addr)), link, remaddr_t);
4608 
4609 	if (unlinked != NULL) {
4610 		DPRINTF(4, ("Deleted addr %s from list of addresses\n",
4611 			stoa(addr)));
4612 		free(unlinked);
4613 	}
4614 }
4615 
4616 
4617 static void
4618 delete_interface_from_list(
4619 	endpt *iface
4620 	)
4621 {
4622 	remaddr_t *unlinked;
4623 
4624 	for (;;) {
4625 		UNLINK_EXPR_SLIST(unlinked, remoteaddr_list, iface ==
4626 		    UNLINK_EXPR_SLIST_CURRENT()->ep, link,
4627 		    remaddr_t);
4628 
4629 		if (unlinked == NULL)
4630 			break;
4631 		DPRINTF(4, ("Deleted addr %s for interface #%d %s from list of addresses\n",
4632 			    stoa(&unlinked->addr), iface->ifnum,
4633 			    iface->name));
4634 		free(unlinked);
4635 	}
4636 }
4637 
4638 
4639 static struct interface *
4640 find_addr_in_list(
4641 	sockaddr_u *addr
4642 	)
4643 {
4644 	remaddr_t *entry;
4645 
4646 	DPRINTF(4, ("Searching for addr %s in list of addresses - ",
4647 		    stoa(addr)));
4648 
4649 	for (entry = remoteaddr_list;
4650 	     entry != NULL;
4651 	     entry = entry->link)
4652 		if (SOCK_EQ(&entry->addr, addr)) {
4653 			DPRINTF(4, ("FOUND\n"));
4654 			return entry->ep;
4655 		}
4656 
4657 	DPRINTF(4, ("NOT FOUND\n"));
4658 	return NULL;
4659 }
4660 
4661 
4662 /*
4663  * Find the given address with the all given flags set in the list
4664  */
4665 static endpt *
4666 find_flagged_addr_in_list(
4667 	sockaddr_u *	addr,
4668 	u_int32		flags
4669 	)
4670 {
4671 	remaddr_t *entry;
4672 
4673 	DPRINTF(4, ("Finding addr %s with flags %d in list: ",
4674 		    stoa(addr), flags));
4675 
4676 	for (entry = remoteaddr_list;
4677 	     entry != NULL;
4678 	     entry = entry->link)
4679 
4680 		if (SOCK_EQ(&entry->addr, addr)
4681 		    && (entry->ep->flags & flags) == flags) {
4682 
4683 			DPRINTF(4, ("FOUND\n"));
4684 			return entry->ep;
4685 		}
4686 
4687 	DPRINTF(4, ("NOT FOUND\n"));
4688 	return NULL;
4689 }
4690 
4691 
4692 const char *
4693 localaddrtoa(
4694 	endpt *la
4695 	)
4696 {
4697 	return (NULL == la)
4698 		   ? "<null>"
4699 		   : stoa(&la->sin);
4700 }
4701 
4702 
4703 #ifdef HAS_ROUTING_SOCKET
4704 # ifndef UPDATE_GRACE
4705 #  define UPDATE_GRACE	2	/* wait UPDATE_GRACE seconds before scanning */
4706 # endif
4707 
4708 static void
4709 process_routing_msgs(struct asyncio_reader *reader)
4710 {
4711 	char buffer[5120];
4712 	int cnt, msg_type;
4713 #ifdef HAVE_RTNETLINK
4714 	struct nlmsghdr *nh;
4715 #else
4716 	struct rt_msghdr rtm;
4717 	char *p;
4718 #endif
4719 
4720 	if (disable_dynamic_updates) {
4721 		/*
4722 		 * discard ourselves if we are not needed any more
4723 		 * usually happens when running unprivileged
4724 		 */
4725 		remove_asyncio_reader(reader);
4726 		delete_asyncio_reader(reader);
4727 		return;
4728 	}
4729 
4730 	cnt = read(reader->fd, buffer, sizeof(buffer));
4731 
4732 	if (cnt < 0) {
4733 		if (errno == ENOBUFS) {
4734 			msyslog(LOG_ERR,
4735 				"routing socket reports: %m");
4736 		} else {
4737 			msyslog(LOG_ERR,
4738 				"routing socket reports: %m - disabling");
4739 			remove_asyncio_reader(reader);
4740 			delete_asyncio_reader(reader);
4741 		}
4742 		return;
4743 	}
4744 
4745 	/*
4746 	 * process routing message
4747 	 */
4748 #ifdef HAVE_RTNETLINK
4749 	for (nh = UA_PTR(struct nlmsghdr, buffer);
4750 	     NLMSG_OK(nh, cnt);
4751 	     nh = NLMSG_NEXT(nh, cnt))
4752 	{
4753 		msg_type = nh->nlmsg_type;
4754 #else
4755 	for (p = buffer;
4756 	     (p + sizeof(struct rt_msghdr)) <= (buffer + cnt);
4757 	     p += rtm.rtm_msglen)
4758 	{
4759 		memcpy(&rtm, p, sizeof(rtm));
4760 		if (rtm.rtm_version != RTM_VERSION) {
4761 			msyslog(LOG_ERR,
4762 				"version mismatch (got %d - expected %d) on routing socket - disabling",
4763 				rtm.rtm_version, RTM_VERSION);
4764 
4765 			remove_asyncio_reader(reader);
4766 			delete_asyncio_reader(reader);
4767 			return;
4768 		}
4769 		msg_type = rtm.rtm_type;
4770 #endif
4771 		switch (msg_type) {
4772 #ifdef RTM_NEWADDR
4773 		case RTM_NEWADDR:
4774 #endif
4775 #ifdef RTM_DELADDR
4776 		case RTM_DELADDR:
4777 #endif
4778 #ifdef RTM_ADD
4779 		case RTM_ADD:
4780 #endif
4781 #ifdef RTM_DELETE
4782 		case RTM_DELETE:
4783 #endif
4784 #ifdef RTM_REDIRECT
4785 		case RTM_REDIRECT:
4786 #endif
4787 #ifdef RTM_CHANGE
4788 		case RTM_CHANGE:
4789 #endif
4790 #ifdef RTM_LOSING
4791 		case RTM_LOSING:
4792 #endif
4793 #ifdef RTM_IFINFO
4794 		case RTM_IFINFO:
4795 #endif
4796 #ifdef RTM_IFANNOUNCE
4797 		case RTM_IFANNOUNCE:
4798 #endif
4799 #ifdef RTM_NEWLINK
4800 		case RTM_NEWLINK:
4801 #endif
4802 #ifdef RTM_DELLINK
4803 		case RTM_DELLINK:
4804 #endif
4805 #ifdef RTM_NEWROUTE
4806 		case RTM_NEWROUTE:
4807 #endif
4808 #ifdef RTM_DELROUTE
4809 		case RTM_DELROUTE:
4810 #endif
4811 			/*
4812 			 * we are keen on new and deleted addresses and
4813 			 * if an interface goes up and down or routing
4814 			 * changes
4815 			 */
4816 			DPRINTF(3, ("routing message op = %d: scheduling interface update\n",
4817 				    msg_type));
4818 			timer_interfacetimeout(current_time + UPDATE_GRACE);
4819 			break;
4820 #ifdef HAVE_RTNETLINK
4821 		case NLMSG_DONE:
4822 			/* end of multipart message */
4823 			return;
4824 #endif
4825 		default:
4826 			/*
4827 			 * the rest doesn't bother us.
4828 			 */
4829 			DPRINTF(4, ("routing message op = %d: ignored\n",
4830 				    msg_type));
4831 			break;
4832 		}
4833 	}
4834 }
4835 
4836 /*
4837  * set up routing notifications
4838  */
4839 static void
4840 init_async_notifications()
4841 {
4842 	struct asyncio_reader *reader;
4843 #ifdef HAVE_RTNETLINK
4844 	int fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
4845 	struct sockaddr_nl sa;
4846 #else
4847 	int fd = socket(PF_ROUTE, SOCK_RAW, 0);
4848 #endif
4849 	if (fd < 0) {
4850 		msyslog(LOG_ERR,
4851 			"unable to open routing socket (%m) - using polled interface update");
4852 		return;
4853 	}
4854 
4855 	fd = move_fd(fd);
4856 #ifdef HAVE_RTNETLINK
4857 	ZERO(sa);
4858 	sa.nl_family = PF_NETLINK;
4859 	sa.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR
4860 		       | RTMGRP_IPV6_IFADDR | RTMGRP_IPV4_ROUTE
4861 		       | RTMGRP_IPV4_MROUTE | RTMGRP_IPV6_ROUTE
4862 		       | RTMGRP_IPV6_MROUTE;
4863 	if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
4864 		msyslog(LOG_ERR,
4865 			"bind failed on routing socket (%m) - using polled interface update");
4866 		return;
4867 	}
4868 #endif
4869 	make_socket_nonblocking(fd);
4870 #if defined(HAVE_SIGNALED_IO)
4871 	init_socket_sig(fd);
4872 #endif /* HAVE_SIGNALED_IO */
4873 
4874 	reader = new_asyncio_reader();
4875 
4876 	reader->fd = fd;
4877 	reader->receiver = process_routing_msgs;
4878 
4879 	add_asyncio_reader(reader, FD_TYPE_SOCKET);
4880 	msyslog(LOG_INFO,
4881 		"Listening on routing socket on fd #%d for interface updates",
4882 		fd);
4883 }
4884 #else
4885 /* HAS_ROUTING_SOCKET not defined */
4886 static void
4887 init_async_notifications(void)
4888 {
4889 }
4890 #endif
4891 
4892