xref: /dragonfly/contrib/dhcpcd/src/dhcpcd.c (revision 9317c2d0)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * dhcpcd - DHCP client daemon
4  * Copyright (c) 2006-2020 Roy Marples <roy@marples.name>
5  * All rights reserved
6 
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 const char dhcpcd_copyright[] = "Copyright (c) 2006-2020 Roy Marples";
30 
31 #include <sys/file.h>
32 #include <sys/ioctl.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/time.h>
36 #include <sys/types.h>
37 #include <sys/uio.h>
38 #include <sys/wait.h>
39 
40 #include <ctype.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <getopt.h>
44 #include <limits.h>
45 #include <paths.h>
46 #include <signal.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <syslog.h>
51 #include <unistd.h>
52 #include <time.h>
53 
54 #include "config.h"
55 #include "arp.h"
56 #include "common.h"
57 #include "control.h"
58 #include "dev.h"
59 #include "dhcp-common.h"
60 #include "dhcpcd.h"
61 #include "dhcp.h"
62 #include "dhcp6.h"
63 #include "duid.h"
64 #include "eloop.h"
65 #include "if.h"
66 #include "if-options.h"
67 #include "ipv4.h"
68 #include "ipv4ll.h"
69 #include "ipv6.h"
70 #include "ipv6nd.h"
71 #include "logerr.h"
72 #include "privsep.h"
73 #include "script.h"
74 
75 #ifdef HAVE_CAPSICUM
76 #include <sys/capsicum.h>
77 #endif
78 #ifdef HAVE_UTIL_H
79 #include <util.h>
80 #endif
81 
82 #ifdef USE_SIGNALS
83 const int dhcpcd_signals[] = {
84 	SIGTERM,
85 	SIGINT,
86 	SIGALRM,
87 	SIGHUP,
88 	SIGUSR1,
89 	SIGUSR2,
90 	SIGCHLD,
91 };
92 const size_t dhcpcd_signals_len = __arraycount(dhcpcd_signals);
93 
94 const int dhcpcd_signals_ignore[] = {
95 	SIGPIPE,
96 };
97 const size_t dhcpcd_signals_ignore_len = __arraycount(dhcpcd_signals_ignore);
98 #endif
99 
100 #define IF_UPANDRUNNING(a) \
101 	(((a)->flags & (IFF_UP | IFF_RUNNING)) == (IFF_UP | IFF_RUNNING))
102 
103 const char *dhcpcd_default_script = SCRIPT;
104 
105 static void
106 usage(void)
107 {
108 
109 printf("usage: "PACKAGE"\t[-146ABbDdEGgHJKLMNPpqTV]\n"
110 	"\t\t[-C, --nohook hook] [-c, --script script]\n"
111 	"\t\t[-e, --env value] [-F, --fqdn FQDN] [-f, --config file]\n"
112 	"\t\t[-h, --hostname hostname] [-I, --clientid clientid]\n"
113 	"\t\t[-i, --vendorclassid vendorclassid] [-j, --logfile logfile]\n"
114 	"\t\t[-l, --leasetime seconds] [-m, --metric metric]\n"
115 	"\t\t[-O, --nooption option] [-o, --option option]\n"
116 	"\t\t[-Q, --require option] [-r, --request address]\n"
117 	"\t\t[-S, --static value]\n"
118 	"\t\t[-s, --inform address[/cidr[/broadcast_address]]]\n [--inform6]"
119 	"\t\t[-t, --timeout seconds] [-u, --userclass class]\n"
120 	"\t\t[-v, --vendor code, value] [-W, --whitelist address[/cidr]] [-w]\n"
121 	"\t\t[--waitip [4 | 6]] [-y, --reboot seconds]\n"
122 	"\t\t[-X, --blacklist address[/cidr]] [-Z, --denyinterfaces pattern]\n"
123 	"\t\t[-z, --allowinterfaces pattern] [--inactive] [interface] [...]\n"
124 	"       "PACKAGE"\t-n, --rebind [interface]\n"
125 	"       "PACKAGE"\t-k, --release [interface]\n"
126 	"       "PACKAGE"\t-U, --dumplease interface\n"
127 	"       "PACKAGE"\t--version\n"
128 	"       "PACKAGE"\t-x, --exit [interface]\n");
129 }
130 
131 static void
132 free_globals(struct dhcpcd_ctx *ctx)
133 {
134 	struct dhcp_opt *opt;
135 
136 	if (ctx->ifac) {
137 		for (; ctx->ifac > 0; ctx->ifac--)
138 			free(ctx->ifav[ctx->ifac - 1]);
139 		free(ctx->ifav);
140 		ctx->ifav = NULL;
141 	}
142 	if (ctx->ifdc) {
143 		for (; ctx->ifdc > 0; ctx->ifdc--)
144 			free(ctx->ifdv[ctx->ifdc - 1]);
145 		free(ctx->ifdv);
146 		ctx->ifdv = NULL;
147 	}
148 	if (ctx->ifcc) {
149 		for (; ctx->ifcc > 0; ctx->ifcc--)
150 			free(ctx->ifcv[ctx->ifcc - 1]);
151 		free(ctx->ifcv);
152 		ctx->ifcv = NULL;
153 	}
154 
155 #ifdef INET
156 	if (ctx->dhcp_opts) {
157 		for (opt = ctx->dhcp_opts;
158 		    ctx->dhcp_opts_len > 0;
159 		    opt++, ctx->dhcp_opts_len--)
160 			free_dhcp_opt_embenc(opt);
161 		free(ctx->dhcp_opts);
162 		ctx->dhcp_opts = NULL;
163 	}
164 #endif
165 #ifdef INET6
166 	if (ctx->nd_opts) {
167 		for (opt = ctx->nd_opts;
168 		    ctx->nd_opts_len > 0;
169 		    opt++, ctx->nd_opts_len--)
170 			free_dhcp_opt_embenc(opt);
171 		free(ctx->nd_opts);
172 		ctx->nd_opts = NULL;
173 	}
174 #ifdef DHCP6
175 	if (ctx->dhcp6_opts) {
176 		for (opt = ctx->dhcp6_opts;
177 		    ctx->dhcp6_opts_len > 0;
178 		    opt++, ctx->dhcp6_opts_len--)
179 			free_dhcp_opt_embenc(opt);
180 		free(ctx->dhcp6_opts);
181 		ctx->dhcp6_opts = NULL;
182 	}
183 #endif
184 #endif
185 	if (ctx->vivso) {
186 		for (opt = ctx->vivso;
187 		    ctx->vivso_len > 0;
188 		    opt++, ctx->vivso_len--)
189 			free_dhcp_opt_embenc(opt);
190 		free(ctx->vivso);
191 		ctx->vivso = NULL;
192 	}
193 }
194 
195 static void
196 handle_exit_timeout(void *arg)
197 {
198 	struct dhcpcd_ctx *ctx;
199 
200 	ctx = arg;
201 	logerrx("timed out");
202 	if (!(ctx->options & DHCPCD_MASTER)) {
203 		struct interface *ifp;
204 
205 		TAILQ_FOREACH(ifp, ctx->ifaces, next) {
206 			if (ifp->active == IF_ACTIVE_USER)
207 				script_runreason(ifp, "STOPPED");
208 		}
209 		eloop_exit(ctx->eloop, EXIT_FAILURE);
210 		return;
211 	}
212 	ctx->options |= DHCPCD_NOWAITIP;
213 	dhcpcd_daemonise(ctx);
214 }
215 
216 static const char *
217 dhcpcd_af(int af)
218 {
219 
220 	switch (af) {
221 	case AF_UNSPEC:
222 		return "IP";
223 	case AF_INET:
224 		return "IPv4";
225 	case AF_INET6:
226 		return "IPv6";
227 	default:
228 		return NULL;
229 	}
230 }
231 
232 int
233 dhcpcd_ifafwaiting(const struct interface *ifp)
234 {
235 	unsigned long long opts;
236 	bool foundany = false;
237 
238 	if (ifp->active != IF_ACTIVE_USER)
239 		return AF_MAX;
240 
241 #define DHCPCD_WAITALL	(DHCPCD_WAITIP4 | DHCPCD_WAITIP6)
242 	opts = ifp->options->options;
243 #ifdef INET
244 	if (opts & DHCPCD_WAITIP4 ||
245 	    (opts & DHCPCD_WAITIP && !(opts & DHCPCD_WAITALL)))
246 	{
247 		bool foundaddr = ipv4_hasaddr(ifp);
248 
249 		if (opts & DHCPCD_WAITIP4 && !foundaddr)
250 			return AF_INET;
251 		if (foundaddr)
252 			foundany = true;
253 	}
254 #endif
255 #ifdef INET6
256 	if (opts & DHCPCD_WAITIP6 ||
257 	    (opts & DHCPCD_WAITIP && !(opts & DHCPCD_WAITALL)))
258 	{
259 		bool foundaddr = ipv6_hasaddr(ifp);
260 
261 		if (opts & DHCPCD_WAITIP6 && !foundaddr)
262 			return AF_INET;
263 		if (foundaddr)
264 			foundany = true;
265 	}
266 #endif
267 
268 	if (opts & DHCPCD_WAITIP && !(opts & DHCPCD_WAITALL) && !foundany)
269 		return AF_UNSPEC;
270 	return AF_MAX;
271 }
272 
273 int
274 dhcpcd_afwaiting(const struct dhcpcd_ctx *ctx)
275 {
276 	unsigned long long opts;
277 	const struct interface *ifp;
278 	int af;
279 
280 	if (!(ctx->options & DHCPCD_WAITOPTS))
281 		return AF_MAX;
282 
283 	opts = ctx->options;
284 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
285 #ifdef INET
286 		if (opts & (DHCPCD_WAITIP | DHCPCD_WAITIP4) &&
287 		    ipv4_hasaddr(ifp))
288 			opts &= ~(DHCPCD_WAITIP | DHCPCD_WAITIP4);
289 #endif
290 #ifdef INET6
291 		if (opts & (DHCPCD_WAITIP | DHCPCD_WAITIP6) &&
292 		    ipv6_hasaddr(ifp))
293 			opts &= ~(DHCPCD_WAITIP | DHCPCD_WAITIP6);
294 #endif
295 		if (!(opts & DHCPCD_WAITOPTS))
296 			break;
297 	}
298 	if (opts & DHCPCD_WAITIP)
299 		af = AF_UNSPEC;
300 	else if (opts & DHCPCD_WAITIP4)
301 		af = AF_INET;
302 	else if (opts & DHCPCD_WAITIP6)
303 		af = AF_INET6;
304 	else
305 		return AF_MAX;
306 	return af;
307 }
308 
309 static int
310 dhcpcd_ipwaited(struct dhcpcd_ctx *ctx)
311 {
312 	struct interface *ifp;
313 	int af;
314 
315 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
316 		if ((af = dhcpcd_ifafwaiting(ifp)) != AF_MAX) {
317 			logdebugx("%s: waiting for an %s address",
318 			    ifp->name, dhcpcd_af(af));
319 			return 0;
320 		}
321 	}
322 
323 	if ((af = dhcpcd_afwaiting(ctx)) != AF_MAX) {
324 		logdebugx("waiting for an %s address",
325 		    dhcpcd_af(af));
326 		return 0;
327 	}
328 
329 	return 1;
330 }
331 
332 /* Returns the pid of the child, otherwise 0. */
333 void
334 dhcpcd_daemonise(struct dhcpcd_ctx *ctx)
335 {
336 #ifdef THERE_IS_NO_FORK
337 	eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx);
338 	errno = ENOSYS;
339 	return 0;
340 #else
341 	int i;
342 	unsigned int logopts = loggetopts();
343 
344 	if (ctx->options & DHCPCD_DAEMONISE &&
345 	    !(ctx->options & (DHCPCD_DAEMONISED | DHCPCD_NOWAITIP)))
346 	{
347 		if (!dhcpcd_ipwaited(ctx))
348 			return;
349 	}
350 
351 	if (ctx->options & DHCPCD_ONESHOT) {
352 		loginfox("exiting due to oneshot");
353 		eloop_exit(ctx->eloop, EXIT_SUCCESS);
354 		return;
355 	}
356 
357 	eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx);
358 	if (ctx->options & DHCPCD_DAEMONISED ||
359 	    !(ctx->options & DHCPCD_DAEMONISE))
360 		return;
361 
362 	/* Don't use loginfo because this makes no sense in a log. */
363 	if (!(logopts & LOGERR_QUIET))
364 		(void)fprintf(stderr, "forked to background, child pid %d\n",
365 		    getpid());
366 	i = EXIT_SUCCESS;
367 	if (write(ctx->fork_fd, &i, sizeof(i)) == -1)
368 		logerr("write");
369 	ctx->options |= DHCPCD_DAEMONISED;
370 	eloop_event_delete(ctx->eloop, ctx->fork_fd);
371 	close(ctx->fork_fd);
372 	ctx->fork_fd = -1;
373 
374 	if (isatty(loggeterrfd())) {
375 		logopts &= ~LOGERR_ERR;
376 		logsetopts(logopts);
377 		logseterrfd(-1);
378 	}
379 #endif
380 }
381 
382 static void
383 dhcpcd_drop(struct interface *ifp, int stop)
384 {
385 
386 #ifdef DHCP6
387 	dhcp6_drop(ifp, stop ? NULL : "EXPIRE6");
388 #endif
389 #ifdef INET6
390 	ipv6nd_drop(ifp);
391 	ipv6_drop(ifp);
392 #endif
393 #ifdef IPV4LL
394 	ipv4ll_drop(ifp);
395 #endif
396 #ifdef INET
397 	dhcp_drop(ifp, stop ? "STOP" : "EXPIRE");
398 #endif
399 #ifdef ARP
400 	arp_drop(ifp);
401 #endif
402 #if !defined(DHCP6) && !defined(DHCP)
403 	UNUSED(stop);
404 #endif
405 }
406 
407 static void
408 stop_interface(struct interface *ifp)
409 {
410 	struct dhcpcd_ctx *ctx;
411 
412 	ctx = ifp->ctx;
413 	loginfox("%s: removing interface", ifp->name);
414 	ifp->options->options |= DHCPCD_STOPPING;
415 
416 	dhcpcd_drop(ifp, 1);
417 	if (ifp->options->options & DHCPCD_DEPARTED)
418 		script_runreason(ifp, "DEPARTED");
419 	else
420 		script_runreason(ifp, "STOPPED");
421 
422 	/* Delete all timeouts for the interfaces */
423 	eloop_q_timeout_delete(ctx->eloop, ELOOP_QUEUE_ALL, NULL, ifp);
424 
425 	/* De-activate the interface */
426 	ifp->active = IF_INACTIVE;
427 	ifp->options->options &= ~DHCPCD_STOPPING;
428 	/* Set the link state to unknown as we're no longer tracking it. */
429 	ifp->carrier = LINK_UNKNOWN;
430 
431 	if (!(ctx->options & (DHCPCD_MASTER | DHCPCD_TEST)))
432 		eloop_exit(ctx->eloop, EXIT_FAILURE);
433 }
434 
435 static void
436 configure_interface1(struct interface *ifp)
437 {
438 	struct if_options *ifo = ifp->options;
439 
440 	/* Do any platform specific configuration */
441 	if_conf(ifp);
442 
443 	/* If we want to release a lease, we can't really persist the
444 	 * address either. */
445 	if (ifo->options & DHCPCD_RELEASE)
446 		ifo->options &= ~DHCPCD_PERSISTENT;
447 
448 	if (ifp->flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) {
449 		ifo->options &= ~DHCPCD_ARP;
450 		if (!(ifp->flags & IFF_MULTICAST))
451 			ifo->options &= ~DHCPCD_IPV6RS;
452 		if (!(ifo->options & (DHCPCD_INFORM | DHCPCD_WANTDHCP)))
453 			ifo->options |= DHCPCD_STATIC;
454 	}
455 
456 	if (ifo->metric != -1)
457 		ifp->metric = (unsigned int)ifo->metric;
458 
459 #ifdef INET6
460 	/* We want to setup INET6 on the interface as soon as possible. */
461 	if (ifp->active == IF_ACTIVE_USER &&
462 	    ifo->options & DHCPCD_IPV6 &&
463 	    !(ifp->ctx->options & (DHCPCD_DUMPLEASE | DHCPCD_TEST)))
464 	{
465 		/* If not doing any DHCP, disable the RDNSS requirement. */
466 		if (!(ifo->options & (DHCPCD_DHCP | DHCPCD_DHCP6)))
467 			ifo->options &= ~DHCPCD_IPV6RA_REQRDNSS;
468 		if_setup_inet6(ifp);
469 	}
470 #endif
471 
472 	if (!(ifo->options & DHCPCD_IAID)) {
473 		/*
474 		 * An IAID is for identifying a unqiue interface within
475 		 * the client. It is 4 bytes long. Working out a default
476 		 * value is problematic.
477 		 *
478 		 * Interface name and number are not stable
479 		 * between different OS's. Some OS's also cannot make
480 		 * up their mind what the interface should be called
481 		 * (yes, udev, I'm looking at you).
482 		 * Also, the name could be longer than 4 bytes.
483 		 * Also, with pluggable interfaces the name and index
484 		 * could easily get swapped per actual interface.
485 		 *
486 		 * The MAC address is 6 bytes long, the final 3
487 		 * being unique to the manufacturer and the initial 3
488 		 * being unique to the organisation which makes it.
489 		 * We could use the last 4 bytes of the MAC address
490 		 * as the IAID as it's the most stable part given the
491 		 * above, but equally it's not guaranteed to be
492 		 * unique.
493 		 *
494 		 * Given the above, and our need to reliably work
495 		 * between reboots without persitent storage,
496 		 * generating the IAID from the MAC address is the only
497 		 * logical default.
498 		 * Saying that, if a VLANID has been specified then we
499 		 * can use that. It's possible that different interfaces
500 		 * can have the same VLANID, but this is no worse than
501 		 * generating the IAID from the duplicate MAC address.
502 		 *
503 		 * dhclient uses the last 4 bytes of the MAC address.
504 		 * dibbler uses an increamenting counter.
505 		 * wide-dhcpv6 uses 0 or a configured value.
506 		 * odhcp6c uses 1.
507 		 * Windows 7 uses the first 3 bytes of the MAC address
508 		 * and an unknown byte.
509 		 * dhcpcd-6.1.0 and earlier used the interface name,
510 		 * falling back to interface index if name > 4.
511 		 */
512 		if (ifp->vlanid != 0) {
513 			uint32_t vlanid;
514 
515 			/* Maximal VLANID is 4095, so prefix with 0xff
516 			 * so we don't conflict with an interface index. */
517 			vlanid = htonl(ifp->vlanid | 0xff000000);
518 			memcpy(ifo->iaid, &vlanid, sizeof(vlanid));
519 		} else if (ifo->options & DHCPCD_ANONYMOUS)
520 			memset(ifo->iaid, 0, sizeof(ifo->iaid));
521 		else if (ifp->hwlen >= sizeof(ifo->iaid)) {
522 			memcpy(ifo->iaid,
523 			    ifp->hwaddr + ifp->hwlen - sizeof(ifo->iaid),
524 			    sizeof(ifo->iaid));
525 		} else {
526 			uint32_t len;
527 
528 			len = (uint32_t)strlen(ifp->name);
529 			if (len <= sizeof(ifo->iaid)) {
530 				memcpy(ifo->iaid, ifp->name, len);
531 				if (len < sizeof(ifo->iaid))
532 					memset(ifo->iaid + len, 0,
533 					    sizeof(ifo->iaid) - len);
534 			} else {
535 				/* IAID is the same size as a uint32_t */
536 				len = htonl(ifp->index);
537 				memcpy(ifo->iaid, &len, sizeof(ifo->iaid));
538 			}
539 		}
540 		ifo->options |= DHCPCD_IAID;
541 	}
542 
543 #ifdef DHCP6
544 	if (ifo->ia_len == 0 && ifo->options & DHCPCD_IPV6 &&
545 	    ifp->name[0] != '\0')
546 	{
547 		ifo->ia = malloc(sizeof(*ifo->ia));
548 		if (ifo->ia == NULL)
549 			logerr(__func__);
550 		else {
551 			ifo->ia_len = 1;
552 			ifo->ia->ia_type = D6_OPTION_IA_NA;
553 			memcpy(ifo->ia->iaid, ifo->iaid, sizeof(ifo->iaid));
554 			memset(&ifo->ia->addr, 0, sizeof(ifo->ia->addr));
555 #ifndef SMALL
556 			ifo->ia->sla = NULL;
557 			ifo->ia->sla_len = 0;
558 #endif
559 		}
560 	} else {
561 		size_t i;
562 
563 		for (i = 0; i < ifo->ia_len; i++) {
564 			if (!ifo->ia[i].iaid_set) {
565 				memcpy(&ifo->ia[i].iaid, ifo->iaid,
566 				    sizeof(ifo->ia[i].iaid));
567 				ifo->ia[i].iaid_set = 1;
568 			}
569 		}
570 	}
571 #endif
572 
573 	/* If root is network mounted, we don't want to kill the connection
574 	 * if the DHCP server goes the way of the dodo OR dhcpcd is rebooting
575 	 * and the lease file has expired. */
576 	if (is_root_local() == 0)
577 		ifo->options |= DHCPCD_LASTLEASE_EXTEND;
578 }
579 
580 int
581 dhcpcd_selectprofile(struct interface *ifp, const char *profile)
582 {
583 	struct if_options *ifo;
584 	char pssid[PROFILE_LEN];
585 
586 	if (ifp->ssid_len) {
587 		ssize_t r;
588 
589 		r = print_string(pssid, sizeof(pssid), OT_ESCSTRING,
590 		    ifp->ssid, ifp->ssid_len);
591 		if (r == -1) {
592 			logerr(__func__);
593 			pssid[0] = '\0';
594 		}
595 	} else
596 		pssid[0] = '\0';
597 	ifo = read_config(ifp->ctx, ifp->name, pssid, profile);
598 	if (ifo == NULL) {
599 		logdebugx("%s: no profile %s", ifp->name, profile);
600 		return -1;
601 	}
602 	if (profile != NULL) {
603 		strlcpy(ifp->profile, profile, sizeof(ifp->profile));
604 		loginfox("%s: selected profile %s", ifp->name, profile);
605 	} else
606 		*ifp->profile = '\0';
607 
608 	free_options(ifp->ctx, ifp->options);
609 	ifp->options = ifo;
610 	if (profile) {
611 		add_options(ifp->ctx, ifp->name, ifp->options,
612 		    ifp->ctx->argc, ifp->ctx->argv);
613 		configure_interface1(ifp);
614 	}
615 	return 1;
616 }
617 
618 static void
619 configure_interface(struct interface *ifp, int argc, char **argv,
620     unsigned long long options)
621 {
622 	time_t old;
623 
624 	old = ifp->options ? ifp->options->mtime : 0;
625 	dhcpcd_selectprofile(ifp, NULL);
626 	if (ifp->options == NULL) {
627 		/* dhcpcd cannot continue with this interface. */
628 		ifp->active = IF_INACTIVE;
629 		return;
630 	}
631 	add_options(ifp->ctx, ifp->name, ifp->options, argc, argv);
632 	ifp->options->options |= options;
633 	configure_interface1(ifp);
634 
635 	/* If the mtime has changed drop any old lease */
636 	if (old != 0 && ifp->options->mtime != old) {
637 		logwarnx("%s: config file changed, expiring leases",
638 		    ifp->name);
639 		dhcpcd_drop(ifp, 0);
640 	}
641 }
642 
643 static void
644 dhcpcd_initstate2(struct interface *ifp, unsigned long long options)
645 {
646 	struct if_options *ifo;
647 
648 	if (options) {
649 		if ((ifo = default_config(ifp->ctx)) == NULL) {
650 			logerr(__func__);
651 			return;
652 		}
653 		ifo->options |= options;
654 		free(ifp->options);
655 		ifp->options = ifo;
656 	} else
657 		ifo = ifp->options;
658 
659 #ifdef INET6
660 	if (ifo->options & DHCPCD_IPV6 && ipv6_init(ifp->ctx) == -1) {
661 		logerr(__func__);
662 		ifo->options &= ~DHCPCD_IPV6;
663 	}
664 #endif
665 }
666 
667 static void
668 dhcpcd_initstate1(struct interface *ifp, int argc, char **argv,
669     unsigned long long options)
670 {
671 
672 	configure_interface(ifp, argc, argv, options);
673 	if (ifp->active)
674 		dhcpcd_initstate2(ifp, 0);
675 }
676 
677 static void
678 dhcpcd_initstate(struct interface *ifp, unsigned long long options)
679 {
680 
681 	dhcpcd_initstate1(ifp, ifp->ctx->argc, ifp->ctx->argv, options);
682 }
683 
684 static void
685 dhcpcd_reportssid(struct interface *ifp)
686 {
687 	char pssid[IF_SSIDLEN * 4];
688 
689 	if (print_string(pssid, sizeof(pssid), OT_ESCSTRING,
690 	    ifp->ssid, ifp->ssid_len) == -1)
691 	{
692 		logerr(__func__);
693 		return;
694 	}
695 
696 	loginfox("%s: connected to Access Point `%s'", ifp->name, pssid);
697 }
698 
699 void
700 dhcpcd_handlecarrier(struct dhcpcd_ctx *ctx, int carrier, unsigned int flags,
701     const char *ifname)
702 {
703 	struct interface *ifp;
704 
705 	ifp = if_find(ctx->ifaces, ifname);
706 	if (ifp == NULL ||
707 	    ifp->options == NULL || !(ifp->options->options & DHCPCD_LINK) ||
708 	    !ifp->active)
709 		return;
710 
711 	if (carrier == LINK_UNKNOWN) {
712 		if (ifp->wireless) {
713 			carrier = LINK_DOWN;
714 			ifp->flags = flags;
715 		} else
716 			carrier = if_carrier(ifp);
717 	} else
718 		ifp->flags = flags;
719 	if (carrier == LINK_UNKNOWN)
720 		carrier = IF_UPANDRUNNING(ifp) ? LINK_UP : LINK_DOWN;
721 
722 	if (carrier == LINK_DOWN || (ifp->flags & IFF_UP) == 0) {
723 		if (ifp->carrier != LINK_DOWN) {
724 			if (ifp->carrier == LINK_UP)
725 				loginfox("%s: carrier lost", ifp->name);
726 #ifdef NOCARRIER_PRESERVE_IP
727 			if (ifp->flags & IFF_UP &&
728 			    !(ifp->options->options & DHCPCD_ANONYMOUS))
729 				ifp->carrier = LINK_DOWN_IFFUP;
730 			else
731 #endif
732 				ifp->carrier = LINK_DOWN;
733 			script_runreason(ifp, "NOCARRIER");
734 #ifdef NOCARRIER_PRESERVE_IP
735 			if (ifp->flags & IFF_UP &&
736 			    !(ifp->options->options & DHCPCD_ANONYMOUS))
737 			{
738 #ifdef ARP
739 				arp_drop(ifp);
740 #endif
741 #ifdef INET
742 				dhcp_abort(ifp);
743 #endif
744 #ifdef DHCP6
745 				dhcp6_abort(ifp);
746 #endif
747 			} else
748 #endif
749 				dhcpcd_drop(ifp, 0);
750 			if (ifp->options->options & DHCPCD_ANONYMOUS) {
751 				bool was_up = ifp->flags & IFF_UP;
752 
753 				if (was_up)
754 					if_down(ifp);
755 				if (if_randomisemac(ifp) == -1 && errno != ENXIO)
756 					logerr(__func__);
757 				if (was_up)
758 					if_up(ifp);
759 			}
760 		}
761 	} else if (carrier == LINK_UP && ifp->flags & IFF_UP) {
762 		if (ifp->carrier != LINK_UP) {
763 			loginfox("%s: carrier acquired", ifp->name);
764 			ifp->carrier = LINK_UP;
765 #if !defined(__linux__) && !defined(__NetBSD__)
766 			/* BSD does not emit RTM_NEWADDR or RTM_CHGADDR when the
767 			 * hardware address changes so we have to go
768 			 * through the disovery process to work it out. */
769 			dhcpcd_handleinterface(ctx, 0, ifp->name);
770 #endif
771 			if (ifp->wireless) {
772 				uint8_t ossid[IF_SSIDLEN];
773 				size_t olen;
774 
775 				olen = ifp->ssid_len;
776 				memcpy(ossid, ifp->ssid, ifp->ssid_len);
777 				if_getssid(ifp);
778 
779 				/* If we changed SSID network, drop leases */
780 				if (ifp->ssid_len != olen ||
781 				    memcmp(ifp->ssid, ossid, ifp->ssid_len))
782 				{
783 					dhcpcd_reportssid(ifp);
784 #ifdef NOCARRIER_PRESERVE_IP
785 					dhcpcd_drop(ifp, 0);
786 #endif
787 #ifdef IPV4LL
788 					ipv4ll_reset(ifp);
789 #endif
790 				}
791 			}
792 			dhcpcd_initstate(ifp, 0);
793 			script_runreason(ifp, "CARRIER");
794 #ifdef INET6
795 #ifdef NOCARRIER_PRESERVE_IP
796 			/* Set any IPv6 Routers we remembered to expire
797 			 * faster than they would normally as we
798 			 * maybe on a new network. */
799 			ipv6nd_startexpire(ifp);
800 #endif
801 #ifdef IPV6_MANAGETEMPADDR
802 			/* RFC4941 Section 3.5 */
803 			ipv6_regentempaddrs(ifp);
804 #endif
805 #endif
806 			dhcpcd_startinterface(ifp);
807 		}
808 	}
809 }
810 
811 static void
812 warn_iaid_conflict(struct interface *ifp, uint16_t ia_type, uint8_t *iaid)
813 {
814 	struct interface *ifn;
815 #ifdef INET6
816 	size_t i;
817 	struct if_ia *ia;
818 #endif
819 
820 	TAILQ_FOREACH(ifn, ifp->ctx->ifaces, next) {
821 		if (ifn == ifp || !ifn->active)
822 			continue;
823 		if (ifn->options->options & DHCPCD_ANONYMOUS)
824 			continue;
825 		if (ia_type == 0 &&
826 		    memcmp(ifn->options->iaid, iaid,
827 		    sizeof(ifn->options->iaid)) == 0)
828 			break;
829 #ifdef INET6
830 		for (i = 0; i < ifn->options->ia_len; i++) {
831 			ia = &ifn->options->ia[i];
832 			if (ia->ia_type == ia_type &&
833 			    memcmp(ia->iaid, iaid, sizeof(ia->iaid)) == 0)
834 				break;
835 		}
836 #endif
837 	}
838 
839 	/* This is only a problem if the interfaces are on the same network. */
840 	if (ifn)
841 		logerrx("%s: IAID conflicts with one assigned to %s",
842 		    ifp->name, ifn->name);
843 }
844 
845 static void
846 dhcpcd_initduid(struct dhcpcd_ctx *ctx, struct interface *ifp)
847 {
848 	char buf[DUID_LEN * 3];
849 
850 	if (ctx->duid != NULL)
851 		return;
852 
853 	duid_init(ctx, ifp);
854 	if (ctx->duid == NULL)
855 		return;
856 
857 	loginfox("DUID %s",
858 	    hwaddr_ntoa(ctx->duid, ctx->duid_len, buf, sizeof(buf)));
859 }
860 
861 void
862 dhcpcd_startinterface(void *arg)
863 {
864 	struct interface *ifp = arg;
865 	struct if_options *ifo = ifp->options;
866 
867 	if (ifo->options & DHCPCD_LINK) {
868 		switch (ifp->carrier) {
869 		case LINK_UP:
870 			break;
871 		case LINK_DOWN:
872 			loginfox("%s: waiting for carrier", ifp->name);
873 			return;
874 		case LINK_UNKNOWN:
875 			/* No media state available.
876 			 * Loop until both IFF_UP and IFF_RUNNING are set */
877 			if (ifo->poll == 0)
878 				if_pollinit(ifp);
879 			return;
880 		}
881 	}
882 
883 	if (ifo->options & (DHCPCD_DUID | DHCPCD_IPV6) &&
884 	    !(ifo->options & DHCPCD_ANONYMOUS))
885 	{
886 		char buf[sizeof(ifo->iaid) * 3];
887 #ifdef INET6
888 		size_t i;
889 		struct if_ia *ia;
890 #endif
891 
892 		/* Try and init DUID from the interface hardware address */
893 		dhcpcd_initduid(ifp->ctx, ifp);
894 
895 		/* Report IAIDs */
896 		loginfox("%s: IAID %s", ifp->name,
897 		    hwaddr_ntoa(ifo->iaid, sizeof(ifo->iaid),
898 		    buf, sizeof(buf)));
899 		warn_iaid_conflict(ifp, 0, ifo->iaid);
900 
901 #ifdef INET6
902 		for (i = 0; i < ifo->ia_len; i++) {
903 			ia = &ifo->ia[i];
904 			if (memcmp(ifo->iaid, ia->iaid, sizeof(ifo->iaid))) {
905 				loginfox("%s: IA type %u IAID %s",
906 				    ifp->name, ia->ia_type,
907 				    hwaddr_ntoa(ia->iaid, sizeof(ia->iaid),
908 				    buf, sizeof(buf)));
909 				warn_iaid_conflict(ifp, ia->ia_type, ia->iaid);
910 			}
911 		}
912 #endif
913 	}
914 
915 #ifdef INET6
916 	if (ifo->options & DHCPCD_IPV6 && ipv6_start(ifp) == -1) {
917 		logerr("%s: ipv6_start", ifp->name);
918 		ifo->options &= ~DHCPCD_IPV6;
919 	}
920 
921 	if (ifo->options & DHCPCD_IPV6) {
922 		if (ifp->active == IF_ACTIVE_USER) {
923 			ipv6_startstatic(ifp);
924 
925 			if (ifo->options & DHCPCD_IPV6RS)
926 				ipv6nd_startrs(ifp);
927 		}
928 
929 #ifdef DHCP6
930 		/* DHCPv6 could be turned off, but the interface
931 		 * is still delegated to. */
932 		if (ifp->active)
933 			dhcp6_find_delegates(ifp);
934 
935 		if (ifo->options & DHCPCD_DHCP6) {
936 			if (ifp->active == IF_ACTIVE_USER) {
937 				enum DH6S d6_state;
938 
939 				if (ifo->options & DHCPCD_IA_FORCED)
940 					d6_state = DH6S_INIT;
941 				else if (ifo->options & DHCPCD_INFORM6)
942 					d6_state = DH6S_INFORM;
943 				else
944 					d6_state = DH6S_CONFIRM;
945 				if (dhcp6_start(ifp, d6_state) == -1)
946 					logerr("%s: dhcp6_start", ifp->name);
947 			}
948 		}
949 #endif
950 	}
951 #endif
952 
953 #ifdef INET
954 	if (ifo->options & DHCPCD_IPV4 && ifp->active == IF_ACTIVE_USER) {
955 		/* Ensure we have an IPv4 state before starting DHCP */
956 		if (ipv4_getstate(ifp) != NULL)
957 			dhcp_start(ifp);
958 	}
959 #endif
960 }
961 
962 static void
963 dhcpcd_prestartinterface(void *arg)
964 {
965 	struct interface *ifp = arg;
966 	struct dhcpcd_ctx *ctx = ifp->ctx;
967 	bool anondown;
968 
969 	if (ifp->carrier == LINK_DOWN &&
970 	    ifp->options->options & DHCPCD_ANONYMOUS &&
971 	    ifp->flags & IFF_UP)
972 	{
973 		if_down(ifp);
974 		anondown = true;
975 	} else
976 		anondown = false;
977 
978 	if ((!(ctx->options & DHCPCD_MASTER) ||
979 	    ifp->options->options & DHCPCD_IF_UP || anondown) &&
980 	    !(ifp->flags & IFF_UP))
981 	{
982 		if (ifp->options->options & DHCPCD_ANONYMOUS &&
983 		    if_randomisemac(ifp) == -1)
984 			logerr(__func__);
985 		if (if_up(ifp) == -1)
986 			logerr(__func__);
987 	}
988 
989 	if (ifp->options->poll != 0)
990 		if_pollinit(ifp);
991 
992 	dhcpcd_startinterface(ifp);
993 }
994 
995 static void
996 run_preinit(struct interface *ifp)
997 {
998 
999 	if (ifp->ctx->options & DHCPCD_TEST)
1000 		return;
1001 
1002 	script_runreason(ifp, "PREINIT");
1003 	if (ifp->wireless && ifp->carrier == LINK_UP)
1004 		dhcpcd_reportssid(ifp);
1005 	if (ifp->options->options & DHCPCD_LINK && ifp->carrier != LINK_UNKNOWN)
1006 		script_runreason(ifp,
1007 		    ifp->carrier == LINK_UP ? "CARRIER" : "NOCARRIER");
1008 }
1009 
1010 void
1011 dhcpcd_activateinterface(struct interface *ifp, unsigned long long options)
1012 {
1013 
1014 	if (!ifp->active) {
1015 		ifp->active = IF_ACTIVE;
1016 		dhcpcd_initstate2(ifp, options);
1017 		/* It's possible we might not have been able to load
1018 		 * a config. */
1019 		if (ifp->active) {
1020 			configure_interface1(ifp);
1021 			run_preinit(ifp);
1022 			dhcpcd_prestartinterface(ifp);
1023 		}
1024 	}
1025 }
1026 
1027 int
1028 dhcpcd_handleinterface(void *arg, int action, const char *ifname)
1029 {
1030 	struct dhcpcd_ctx *ctx;
1031 	struct ifaddrs *ifaddrs;
1032 	struct if_head *ifs;
1033 	struct interface *ifp, *iff;
1034 	const char * const argv[] = { ifname };
1035 	int e;
1036 
1037 	ctx = arg;
1038 	if (action == -1) {
1039 		ifp = if_find(ctx->ifaces, ifname);
1040 		if (ifp == NULL) {
1041 			errno = ESRCH;
1042 			return -1;
1043 		}
1044 		if (ifp->active) {
1045 			logdebugx("%s: interface departed", ifp->name);
1046 			ifp->options->options |= DHCPCD_DEPARTED;
1047 			stop_interface(ifp);
1048 		}
1049 		TAILQ_REMOVE(ctx->ifaces, ifp, next);
1050 		if_free(ifp);
1051 		return 0;
1052 	}
1053 
1054 	ifs = if_discover(ctx, &ifaddrs, -1, UNCONST(argv));
1055 	if (ifs == NULL) {
1056 		logerr(__func__);
1057 		return -1;
1058 	}
1059 
1060 	ifp = if_find(ifs, ifname);
1061 	if (ifp == NULL) {
1062 		/* This can happen if an interface is quickly added
1063 		 * and then removed. */
1064 		errno = ENOENT;
1065 		e = -1;
1066 		goto out;
1067 	}
1068 	e = 1;
1069 
1070 	/* Check if we already have the interface */
1071 	iff = if_find(ctx->ifaces, ifp->name);
1072 
1073 	if (iff != NULL) {
1074 		if (iff->active)
1075 			logdebugx("%s: interface updated", iff->name);
1076 		/* The flags and hwaddr could have changed */
1077 		iff->flags = ifp->flags;
1078 		iff->hwlen = ifp->hwlen;
1079 		if (ifp->hwlen != 0)
1080 			memcpy(iff->hwaddr, ifp->hwaddr, iff->hwlen);
1081 	} else {
1082 		TAILQ_REMOVE(ifs, ifp, next);
1083 		TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next);
1084 		if (ifp->active) {
1085 			logdebugx("%s: interface added", ifp->name);
1086 			dhcpcd_initstate(ifp, 0);
1087 			run_preinit(ifp);
1088 		}
1089 		iff = ifp;
1090 	}
1091 
1092 	if (action > 0) {
1093 		if_learnaddrs(ctx, ifs, &ifaddrs);
1094 		if (iff->active)
1095 			dhcpcd_prestartinterface(iff);
1096 	}
1097 
1098 out:
1099 	/* Free our discovered list */
1100 	while ((ifp = TAILQ_FIRST(ifs))) {
1101 		TAILQ_REMOVE(ifs, ifp, next);
1102 		if_free(ifp);
1103 	}
1104 	free(ifs);
1105 
1106 	return e;
1107 }
1108 
1109 static void
1110 dhcpcd_handlelink(void *arg)
1111 {
1112 	struct dhcpcd_ctx *ctx = arg;
1113 
1114 	if (if_handlelink(ctx) == -1) {
1115 		if (errno == ENOBUFS || errno == ENOMEM) {
1116 			dhcpcd_linkoverflow(ctx);
1117 			return;
1118 		}
1119 		if (errno != ENOTSUP)
1120 			logerr(__func__);
1121 	}
1122 }
1123 
1124 static void
1125 dhcpcd_checkcarrier(void *arg)
1126 {
1127 	struct interface *ifp = arg;
1128 	int carrier;
1129 
1130 	/* Check carrier here rather than setting LINK_UNKNOWN.
1131 	 * This is because we force LINK_UNKNOWN as down for wireless which
1132 	 * we do not want when dealing with a route socket overflow. */
1133 	carrier = if_carrier(ifp);
1134 	dhcpcd_handlecarrier(ifp->ctx, carrier, ifp->flags, ifp->name);
1135 }
1136 
1137 #ifndef SMALL
1138 static void
1139 dhcpcd_setlinkrcvbuf(struct dhcpcd_ctx *ctx)
1140 {
1141 	socklen_t socklen;
1142 
1143 	if (ctx->link_rcvbuf == 0)
1144 		return;
1145 
1146 	logdebugx("setting route socket receive buffer size to %d bytes",
1147 	    ctx->link_rcvbuf);
1148 
1149 	socklen = sizeof(ctx->link_rcvbuf);
1150 	if (setsockopt(ctx->link_fd, SOL_SOCKET,
1151 	    SO_RCVBUF, &ctx->link_rcvbuf, socklen) == -1)
1152 		logerr(__func__);
1153 }
1154 #endif
1155 
1156 void
1157 dhcpcd_linkoverflow(struct dhcpcd_ctx *ctx)
1158 {
1159 	socklen_t socklen;
1160 	int rcvbuflen;
1161 	char buf[2048];
1162 	ssize_t rlen;
1163 	size_t rcnt;
1164 	struct if_head *ifaces;
1165 	struct ifaddrs *ifaddrs;
1166 	struct interface *ifp, *ifn, *ifp1;
1167 
1168 	socklen = sizeof(rcvbuflen);
1169 	if (getsockopt(ctx->link_fd, SOL_SOCKET,
1170 	    SO_RCVBUF, &rcvbuflen, &socklen) == -1)
1171 		rcvbuflen = 0;
1172 #ifdef __linux__
1173 	else
1174 		rcvbuflen /= 2;
1175 #endif
1176 
1177 	logerrx("route socket overflowed (rcvbuflen %d)"
1178 	    " - learning interface state", rcvbuflen);
1179 
1180 	/* Drain the socket.
1181 	 * We cannot open a new one due to privsep. */
1182 	rcnt = 0;
1183 	do {
1184 		rlen = read(ctx->link_fd, buf, sizeof(buf));
1185 		if (++rcnt % 1000 == 0)
1186 			logwarnx("drained %zu messages", rcnt);
1187 	} while (rlen != -1 || errno == ENOBUFS || errno == ENOMEM);
1188 	if (rcnt % 1000 != 0)
1189 		logwarnx("drained %zu messages", rcnt);
1190 
1191 	/* Work out the current interfaces. */
1192 	ifaces = if_discover(ctx, &ifaddrs, ctx->ifc, ctx->ifv);
1193 	if (ifaces == NULL) {
1194 		logerr(__func__);
1195 		return;
1196 	}
1197 
1198 	/* Punt departed interfaces */
1199 	TAILQ_FOREACH_SAFE(ifp, ctx->ifaces, next, ifn) {
1200 		if (if_find(ifaces, ifp->name) != NULL)
1201 			continue;
1202 		dhcpcd_handleinterface(ctx, -1, ifp->name);
1203 	}
1204 
1205 	/* Add new interfaces */
1206 	while ((ifp = TAILQ_FIRST(ifaces)) != NULL ) {
1207 		TAILQ_REMOVE(ifaces, ifp, next);
1208 		ifp1 = if_find(ctx->ifaces, ifp->name);
1209 		if (ifp1 != NULL) {
1210 			/* If the interface already exists,
1211 			 * check carrier state. */
1212 			eloop_timeout_add_sec(ctx->eloop, 0,
1213 			    dhcpcd_checkcarrier, ifp1);
1214 			if_free(ifp);
1215 			continue;
1216 		}
1217 		TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next);
1218 		if (ifp->active)
1219 			eloop_timeout_add_sec(ctx->eloop, 0,
1220 			    dhcpcd_prestartinterface, ifp);
1221 	}
1222 	free(ifaces);
1223 
1224 	/* Update address state. */
1225 	if_markaddrsstale(ctx->ifaces);
1226 	if_learnaddrs(ctx, ctx->ifaces, &ifaddrs);
1227 	if_deletestaleaddrs(ctx->ifaces);
1228 }
1229 
1230 void
1231 dhcpcd_handlehwaddr(struct interface *ifp,
1232     uint16_t hwtype, const void *hwaddr, uint8_t hwlen)
1233 {
1234 	char buf[sizeof(ifp->hwaddr) * 3];
1235 
1236 	if (hwaddr == NULL || !if_valid_hwaddr(hwaddr, hwlen))
1237 		hwlen = 0;
1238 
1239 	if (hwlen > sizeof(ifp->hwaddr)) {
1240 		errno = ENOBUFS;
1241 		logerr("%s: %s", __func__, ifp->name);
1242 		return;
1243 	}
1244 
1245 	if (ifp->hwtype != hwtype) {
1246 		loginfox("%s: hardware address type changed from %d to %d",
1247 		    ifp->name, ifp->hwtype, hwtype);
1248 		ifp->hwtype = hwtype;
1249 	}
1250 
1251 	if (ifp->hwlen == hwlen &&
1252 	    (hwlen == 0 || memcmp(ifp->hwaddr, hwaddr, hwlen) == 0))
1253 		return;
1254 
1255 	loginfox("%s: new hardware address: %s", ifp->name,
1256 	    hwaddr_ntoa(hwaddr, hwlen, buf, sizeof(buf)));
1257 	ifp->hwlen = hwlen;
1258 	if (hwaddr != NULL)
1259 		memcpy(ifp->hwaddr, hwaddr, hwlen);
1260 }
1261 
1262 static void
1263 if_reboot(struct interface *ifp, int argc, char **argv)
1264 {
1265 #ifdef INET
1266 	unsigned long long oldopts;
1267 
1268 	oldopts = ifp->options->options;
1269 #endif
1270 	script_runreason(ifp, "RECONFIGURE");
1271 	dhcpcd_initstate1(ifp, argc, argv, 0);
1272 #ifdef INET
1273 	dhcp_reboot_newopts(ifp, oldopts);
1274 #endif
1275 #ifdef DHCP6
1276 	dhcp6_reboot(ifp);
1277 #endif
1278 	dhcpcd_prestartinterface(ifp);
1279 }
1280 
1281 static void
1282 reload_config(struct dhcpcd_ctx *ctx)
1283 {
1284 	struct if_options *ifo;
1285 
1286 	free_globals(ctx);
1287 	if ((ifo = read_config(ctx, NULL, NULL, NULL)) == NULL)
1288 		return;
1289 	add_options(ctx, NULL, ifo, ctx->argc, ctx->argv);
1290 	/* We need to preserve these options. */
1291 	if (ctx->options & DHCPCD_STARTED)
1292 		ifo->options |= DHCPCD_STARTED;
1293 	if (ctx->options & DHCPCD_MASTER)
1294 		ifo->options |= DHCPCD_MASTER;
1295 	if (ctx->options & DHCPCD_DAEMONISED)
1296 		ifo->options |= DHCPCD_DAEMONISED;
1297 	if (ctx->options & DHCPCD_PRIVSEP)
1298 		ifo->options |= DHCPCD_PRIVSEP;
1299 	ctx->options = ifo->options;
1300 	free_options(ctx, ifo);
1301 }
1302 
1303 static void
1304 reconf_reboot(struct dhcpcd_ctx *ctx, int action, int argc, char **argv, int oi)
1305 {
1306 	int i;
1307 	struct interface *ifp;
1308 
1309 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1310 		for (i = oi; i < argc; i++) {
1311 			if (strcmp(ifp->name, argv[i]) == 0)
1312 				break;
1313 		}
1314 		if (oi != argc && i == argc)
1315 			continue;
1316 		if (ifp->active == IF_ACTIVE_USER) {
1317 			if (action)
1318 				if_reboot(ifp, argc, argv);
1319 #ifdef INET
1320 			else
1321 				ipv4_applyaddr(ifp);
1322 #endif
1323 		} else if (i != argc) {
1324 			ifp->active = IF_ACTIVE_USER;
1325 			dhcpcd_initstate1(ifp, argc, argv, 0);
1326 			run_preinit(ifp);
1327 			dhcpcd_prestartinterface(ifp);
1328 		}
1329 	}
1330 }
1331 
1332 static void
1333 stop_all_interfaces(struct dhcpcd_ctx *ctx, unsigned long long opts)
1334 {
1335 	struct interface *ifp;
1336 
1337 	ctx->options |= DHCPCD_EXITING;
1338 	if (ctx->ifaces == NULL)
1339 		return;
1340 
1341 	/* Drop the last interface first */
1342 	TAILQ_FOREACH_REVERSE(ifp, ctx->ifaces, if_head, next) {
1343 		if (!ifp->active)
1344 			continue;
1345 		ifp->options->options |= opts;
1346 		if (ifp->options->options & DHCPCD_RELEASE)
1347 			ifp->options->options &= ~DHCPCD_PERSISTENT;
1348 		ifp->options->options |= DHCPCD_EXITING;
1349 		stop_interface(ifp);
1350 	}
1351 }
1352 
1353 static void
1354 dhcpcd_ifrenew(struct interface *ifp)
1355 {
1356 
1357 	if (!ifp->active)
1358 		return;
1359 
1360 	if (ifp->options->options & DHCPCD_LINK &&
1361 	    ifp->carrier == LINK_DOWN)
1362 		return;
1363 
1364 #ifdef INET
1365 	dhcp_renew(ifp);
1366 #endif
1367 #ifdef INET6
1368 #define DHCPCD_RARENEW (DHCPCD_IPV6 | DHCPCD_IPV6RS)
1369 	if ((ifp->options->options & DHCPCD_RARENEW) == DHCPCD_RARENEW)
1370 		ipv6nd_startrs(ifp);
1371 #endif
1372 #ifdef DHCP6
1373 	dhcp6_renew(ifp);
1374 #endif
1375 }
1376 
1377 static void
1378 dhcpcd_renew(struct dhcpcd_ctx *ctx)
1379 {
1380 	struct interface *ifp;
1381 
1382 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1383 		dhcpcd_ifrenew(ifp);
1384 	}
1385 }
1386 
1387 #ifdef USE_SIGNALS
1388 #define sigmsg "received %s, %s"
1389 static void
1390 dhcpcd_signal_cb(int sig, void *arg)
1391 {
1392 	struct dhcpcd_ctx *ctx = arg;
1393 	unsigned long long opts;
1394 	int exit_code;
1395 
1396 	if (ctx->options & DHCPCD_DUMPLEASE) {
1397 		eloop_exit(ctx->eloop, EXIT_FAILURE);
1398 		return;
1399 	}
1400 
1401 	if (sig != SIGCHLD && ctx->options & DHCPCD_FORKED) {
1402 		if (sig == SIGHUP)
1403 			return;
1404 
1405 		pid_t pid = pidfile_read(ctx->pidfile);
1406 		if (pid == -1) {
1407 			if (errno != ENOENT)
1408 				logerr("%s: pidfile_read",__func__);
1409 		} else if (pid == 0)
1410 			logerr("%s: pid cannot be zero", __func__);
1411 		else if (kill(pid, sig) == -1)
1412 			logerr("%s: kill", __func__);
1413 		return;
1414 	}
1415 
1416 	opts = 0;
1417 	exit_code = EXIT_FAILURE;
1418 	switch (sig) {
1419 	case SIGINT:
1420 		loginfox(sigmsg, "SIGINT", "stopping");
1421 		break;
1422 	case SIGTERM:
1423 		loginfox(sigmsg, "SIGTERM", "stopping");
1424 		exit_code = EXIT_SUCCESS;
1425 		break;
1426 	case SIGALRM:
1427 		loginfox(sigmsg, "SIGALRM", "releasing");
1428 		opts |= DHCPCD_RELEASE;
1429 		exit_code = EXIT_SUCCESS;
1430 		break;
1431 	case SIGHUP:
1432 		loginfox(sigmsg, "SIGHUP", "rebinding");
1433 		reload_config(ctx);
1434 		/* Preserve any options passed on the commandline
1435 		 * when we were started. */
1436 		reconf_reboot(ctx, 1, ctx->argc, ctx->argv,
1437 		    ctx->argc - ctx->ifc);
1438 		return;
1439 	case SIGUSR1:
1440 		loginfox(sigmsg, "SIGUSR1", "renewing");
1441 		dhcpcd_renew(ctx);
1442 		return;
1443 	case SIGUSR2:
1444 		loginfox(sigmsg, "SIGUSR2", "reopening log");
1445 		/* XXX This may not work that well in a chroot */
1446 		logclose();
1447 		if (logopen(ctx->logfile) == -1)
1448 			logerr(__func__);
1449 		return;
1450 	case SIGCHLD:
1451 		while (waitpid(-1, NULL, WNOHANG) > 0)
1452 			;
1453 		return;
1454 	default:
1455 		logerrx("received signal %d but don't know what to do with it",
1456 		    sig);
1457 		return;
1458 	}
1459 
1460 	if (!(ctx->options & DHCPCD_TEST))
1461 		stop_all_interfaces(ctx, opts);
1462 	eloop_exit(ctx->eloop, exit_code);
1463 }
1464 #endif
1465 
1466 int
1467 dhcpcd_handleargs(struct dhcpcd_ctx *ctx, struct fd_list *fd,
1468     int argc, char **argv)
1469 {
1470 	struct interface *ifp;
1471 	unsigned long long opts;
1472 	int opt, oi, do_reboot, do_renew, af = AF_UNSPEC;
1473 	size_t len, l, nifaces;
1474 	char *tmp, *p;
1475 
1476 	/* Special commands for our control socket
1477 	 * as the other end should be blocking until it gets the
1478 	 * expected reply we should be safely able just to change the
1479 	 * write callback on the fd */
1480 	/* Make any change here in privsep-control.c as well. */
1481 	if (strcmp(*argv, "--version") == 0) {
1482 		return control_queue(fd, UNCONST(VERSION),
1483 		    strlen(VERSION) + 1);
1484 	} else if (strcmp(*argv, "--getconfigfile") == 0) {
1485 		return control_queue(fd, UNCONST(fd->ctx->cffile),
1486 		    strlen(fd->ctx->cffile) + 1);
1487 	} else if (strcmp(*argv, "--getinterfaces") == 0) {
1488 		optind = argc = 0;
1489 		goto dumplease;
1490 	} else if (strcmp(*argv, "--listen") == 0) {
1491 		fd->flags |= FD_LISTEN;
1492 		return 0;
1493 	}
1494 
1495 	/* Log the command */
1496 	len = 1;
1497 	for (opt = 0; opt < argc; opt++)
1498 		len += strlen(argv[opt]) + 1;
1499 	tmp = malloc(len);
1500 	if (tmp == NULL)
1501 		return -1;
1502 	p = tmp;
1503 	for (opt = 0; opt < argc; opt++) {
1504 		l = strlen(argv[opt]);
1505 		strlcpy(p, argv[opt], len);
1506 		len -= l + 1;
1507 		p += l;
1508 		*p++ = ' ';
1509 	}
1510 	*--p = '\0';
1511 	loginfox("control command: %s", tmp);
1512 	free(tmp);
1513 
1514 	optind = 0;
1515 	oi = 0;
1516 	opts = 0;
1517 	do_reboot = do_renew = 0;
1518 	while ((opt = getopt_long(argc, argv, IF_OPTS, cf_options, &oi)) != -1)
1519 	{
1520 		switch (opt) {
1521 		case 'g':
1522 			/* Assumed if below not set */
1523 			break;
1524 		case 'k':
1525 			opts |= DHCPCD_RELEASE;
1526 			break;
1527 		case 'n':
1528 			do_reboot = 1;
1529 			break;
1530 		case 'p':
1531 			opts |= DHCPCD_PERSISTENT;
1532 			break;
1533 		case 'x':
1534 			opts |= DHCPCD_EXITING;
1535 			break;
1536 		case 'N':
1537 			do_renew = 1;
1538 			break;
1539 		case 'U':
1540 			opts |= DHCPCD_DUMPLEASE;
1541 			break;
1542 		case '4':
1543 			af = AF_INET;
1544 			break;
1545 		case '6':
1546 			af = AF_INET6;
1547 			break;
1548 		}
1549 	}
1550 
1551 	if (opts & DHCPCD_DUMPLEASE) {
1552 		ctx->options |= DHCPCD_DUMPLEASE;
1553 dumplease:
1554 		nifaces = 0;
1555 		TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1556 			if (!ifp->active)
1557 				continue;
1558 			for (oi = optind; oi < argc; oi++) {
1559 				if (strcmp(ifp->name, argv[oi]) == 0)
1560 					break;
1561 			}
1562 			if (optind == argc || oi < argc) {
1563 				opt = send_interface(NULL, ifp, af);
1564 				if (opt == -1)
1565 					goto dumperr;
1566 				nifaces += (size_t)opt;
1567 			}
1568 		}
1569 		if (write(fd->fd, &nifaces, sizeof(nifaces)) != sizeof(nifaces))
1570 			goto dumperr;
1571 		TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1572 			if (!ifp->active)
1573 				continue;
1574 			for (oi = optind; oi < argc; oi++) {
1575 				if (strcmp(ifp->name, argv[oi]) == 0)
1576 					break;
1577 			}
1578 			if (optind == argc || oi < argc) {
1579 				if (send_interface(fd, ifp, af) == -1)
1580 					goto dumperr;
1581 			}
1582 		}
1583 		ctx->options &= ~DHCPCD_DUMPLEASE;
1584 		return 0;
1585 dumperr:
1586 		ctx->options &= ~DHCPCD_DUMPLEASE;
1587 		return -1;
1588 	}
1589 
1590 	/* Only privileged users can control dhcpcd via the socket. */
1591 	if (fd->flags & FD_UNPRIV) {
1592 		errno = EPERM;
1593 		return -1;
1594 	}
1595 
1596 	if (opts & (DHCPCD_EXITING | DHCPCD_RELEASE)) {
1597 		if (optind == argc) {
1598 			stop_all_interfaces(ctx, opts);
1599 			eloop_exit(ctx->eloop, EXIT_SUCCESS);
1600 			return 0;
1601 		}
1602 		for (oi = optind; oi < argc; oi++) {
1603 			if ((ifp = if_find(ctx->ifaces, argv[oi])) == NULL)
1604 				continue;
1605 			if (!ifp->active)
1606 				continue;
1607 			ifp->options->options |= opts;
1608 			if (opts & DHCPCD_RELEASE)
1609 				ifp->options->options &= ~DHCPCD_PERSISTENT;
1610 			stop_interface(ifp);
1611 		}
1612 		return 0;
1613 	}
1614 
1615 	if (do_renew) {
1616 		if (optind == argc) {
1617 			dhcpcd_renew(ctx);
1618 			return 0;
1619 		}
1620 		for (oi = optind; oi < argc; oi++) {
1621 			if ((ifp = if_find(ctx->ifaces, argv[oi])) == NULL)
1622 				continue;
1623 			dhcpcd_ifrenew(ifp);
1624 		}
1625 		return 0;
1626 	}
1627 
1628 	reload_config(ctx);
1629 	/* XXX: Respect initial commandline options? */
1630 	reconf_reboot(ctx, do_reboot, argc, argv, optind - 1);
1631 	return 0;
1632 }
1633 
1634 static void dhcpcd_readdump1(void *);
1635 
1636 static void
1637 dhcpcd_readdump2(void *arg)
1638 {
1639 	struct dhcpcd_ctx *ctx = arg;
1640 	ssize_t len;
1641 	int exit_code = EXIT_FAILURE;
1642 
1643 	len = read(ctx->control_fd, ctx->ctl_buf + ctx->ctl_bufpos,
1644 	    ctx->ctl_buflen - ctx->ctl_bufpos);
1645 	if (len == -1) {
1646 		logerr(__func__);
1647 		goto finished;
1648 	} else if (len == 0)
1649 		goto finished;
1650 	if ((size_t)len + ctx->ctl_bufpos != ctx->ctl_buflen) {
1651 		ctx->ctl_bufpos += (size_t)len;
1652 		return;
1653 	}
1654 
1655 	if (ctx->ctl_buf[ctx->ctl_buflen - 1] != '\0') /* unlikely */
1656 		ctx->ctl_buf[ctx->ctl_buflen - 1] = '\0';
1657 	script_dump(ctx->ctl_buf, ctx->ctl_buflen);
1658 	fflush(stdout);
1659 	if (--ctx->ctl_extra != 0) {
1660 		putchar('\n');
1661 		eloop_event_add(ctx->eloop, ctx->control_fd,
1662 		    dhcpcd_readdump1, ctx);
1663 		return;
1664 	}
1665 	exit_code = EXIT_SUCCESS;
1666 
1667 finished:
1668 	shutdown(ctx->control_fd, SHUT_RDWR);
1669 	eloop_exit(ctx->eloop, exit_code);
1670 }
1671 
1672 static void
1673 dhcpcd_readdump1(void *arg)
1674 {
1675 	struct dhcpcd_ctx *ctx = arg;
1676 	ssize_t len;
1677 
1678 	len = read(ctx->control_fd, &ctx->ctl_buflen, sizeof(ctx->ctl_buflen));
1679 	if (len != sizeof(ctx->ctl_buflen)) {
1680 		if (len != -1)
1681 			errno = EINVAL;
1682 		goto err;
1683 	}
1684 	if (ctx->ctl_buflen > SSIZE_MAX) {
1685 		errno = ENOBUFS;
1686 		goto err;
1687 	}
1688 
1689 	free(ctx->ctl_buf);
1690 	ctx->ctl_buf = malloc(ctx->ctl_buflen);
1691 	if (ctx->ctl_buf == NULL)
1692 		goto err;
1693 
1694 	ctx->ctl_bufpos = 0;
1695 	eloop_event_add(ctx->eloop, ctx->control_fd,
1696 	    dhcpcd_readdump2, ctx);
1697 	return;
1698 
1699 err:
1700 	logerr(__func__);
1701 	eloop_exit(ctx->eloop, EXIT_FAILURE);
1702 }
1703 
1704 static void
1705 dhcpcd_readdump0(void *arg)
1706 {
1707 	struct dhcpcd_ctx *ctx = arg;
1708 	ssize_t len;
1709 
1710 	len = read(ctx->control_fd, &ctx->ctl_extra, sizeof(ctx->ctl_extra));
1711 	if (len != sizeof(ctx->ctl_extra)) {
1712 		if (len != -1)
1713 			errno = EINVAL;
1714 		logerr(__func__);
1715 		eloop_exit(ctx->eloop, EXIT_FAILURE);
1716 		return;
1717 	}
1718 
1719 	if (ctx->ctl_extra == 0) {
1720 		eloop_exit(ctx->eloop, EXIT_SUCCESS);
1721 		return;
1722 	}
1723 
1724 	eloop_event_add(ctx->eloop, ctx->control_fd,
1725 	    dhcpcd_readdump1, ctx);
1726 }
1727 
1728 static void
1729 dhcpcd_readdumptimeout(void *arg)
1730 {
1731 	struct dhcpcd_ctx *ctx = arg;
1732 
1733 	logerrx(__func__);
1734 	eloop_exit(ctx->eloop, EXIT_FAILURE);
1735 }
1736 
1737 static int
1738 dhcpcd_readdump(struct dhcpcd_ctx *ctx)
1739 {
1740 
1741 	ctx->options |=	DHCPCD_FORKED;
1742 	if (eloop_timeout_add_sec(ctx->eloop, 5,
1743 	    dhcpcd_readdumptimeout, ctx) == -1)
1744 		return -1;
1745 	return eloop_event_add(ctx->eloop, ctx->control_fd,
1746 	    dhcpcd_readdump0, ctx);
1747 }
1748 
1749 static void
1750 dhcpcd_fork_cb(void *arg)
1751 {
1752 	struct dhcpcd_ctx *ctx = arg;
1753 	int exit_code;
1754 	ssize_t len;
1755 
1756 	len = read(ctx->fork_fd, &exit_code, sizeof(exit_code));
1757 	if (len == -1) {
1758 		logerr(__func__);
1759 		exit_code = EXIT_FAILURE;
1760 	} else if ((size_t)len < sizeof(exit_code)) {
1761 		logerrx("%s: truncated read %zd (expected %zu)",
1762 		    __func__, len, sizeof(exit_code));
1763 		exit_code = EXIT_FAILURE;
1764 	}
1765 	eloop_exit(ctx->eloop, exit_code);
1766 }
1767 
1768 int
1769 main(int argc, char **argv)
1770 {
1771 	struct dhcpcd_ctx ctx;
1772 	struct ifaddrs *ifaddrs = NULL;
1773 	struct if_options *ifo;
1774 	struct interface *ifp;
1775 	sa_family_t family = AF_UNSPEC;
1776 	int opt, oi = 0, i;
1777 	unsigned int logopts, t;
1778 	ssize_t len;
1779 #if defined(USE_SIGNALS) || !defined(THERE_IS_NO_FORK)
1780 	pid_t pid;
1781 	int sigpipe[2];
1782 #endif
1783 #ifdef USE_SIGNALS
1784 	int sig = 0;
1785 	const char *siga = NULL;
1786 	size_t si;
1787 #endif
1788 
1789 	/* Test for --help and --version */
1790 	if (argc > 1) {
1791 		if (strcmp(argv[1], "--help") == 0) {
1792 			usage();
1793 			return EXIT_SUCCESS;
1794 		} else if (strcmp(argv[1], "--version") == 0) {
1795 			printf(""PACKAGE" "VERSION"\n%s\n", dhcpcd_copyright);
1796 			printf("Compiled in features:"
1797 #ifdef INET
1798 			" INET"
1799 #endif
1800 #ifdef ARP
1801 			" ARP"
1802 #endif
1803 #ifdef ARPING
1804 			" ARPing"
1805 #endif
1806 #ifdef IPV4LL
1807 			" IPv4LL"
1808 #endif
1809 #ifdef INET6
1810 			" INET6"
1811 #endif
1812 #ifdef DHCP6
1813 			" DHCPv6"
1814 #endif
1815 #ifdef AUTH
1816 			" AUTH"
1817 #endif
1818 #ifdef PRIVSEP
1819 			" PRIVSEP"
1820 #endif
1821 			"\n");
1822 			return EXIT_SUCCESS;
1823 		}
1824 	}
1825 
1826 	memset(&ctx, 0, sizeof(ctx));
1827 
1828 	ifo = NULL;
1829 	ctx.cffile = CONFIG;
1830 	ctx.script = UNCONST(dhcpcd_default_script);
1831 	ctx.control_fd = ctx.control_unpriv_fd = ctx.link_fd = -1;
1832 	ctx.pf_inet_fd = -1;
1833 #ifdef PF_LINK
1834 	ctx.pf_link_fd = -1;
1835 #endif
1836 
1837 	TAILQ_INIT(&ctx.control_fds);
1838 #ifdef USE_SIGNALS
1839 	ctx.fork_fd = -1;
1840 #endif
1841 #ifdef PLUGIN_DEV
1842 	ctx.dev_fd = -1;
1843 #endif
1844 #ifdef INET
1845 	ctx.udp_rfd = -1;
1846 	ctx.udp_wfd = -1;
1847 #endif
1848 #if defined(INET6) && !defined(__sun)
1849 	ctx.nd_fd = -1;
1850 #endif
1851 #ifdef DHCP6
1852 	ctx.dhcp6_rfd = -1;
1853 	ctx.dhcp6_wfd = -1;
1854 #endif
1855 #ifdef PRIVSEP
1856 	ctx.ps_root_fd = ctx.ps_data_fd = -1;
1857 	ctx.ps_inet_fd = ctx.ps_control_fd = -1;
1858 	TAILQ_INIT(&ctx.ps_processes);
1859 #endif
1860 	rt_init(&ctx);
1861 
1862 	logopts = LOGERR_ERR|LOGERR_LOG|LOGERR_LOG_DATE|LOGERR_LOG_PID;
1863 	i = 0;
1864 	while ((opt = getopt_long(argc, argv,
1865 	    ctx.options & DHCPCD_PRINT_PIDFILE ? NOERR_IF_OPTS : IF_OPTS,
1866 	    cf_options, &oi)) != -1)
1867 	{
1868 		switch (opt) {
1869 		case '4':
1870 			family = AF_INET;
1871 			break;
1872 		case '6':
1873 			family = AF_INET6;
1874 			break;
1875 		case 'f':
1876 			ctx.cffile = optarg;
1877 			break;
1878 		case 'j':
1879 			free(ctx.logfile);
1880 			ctx.logfile = strdup(optarg);
1881 			break;
1882 #ifdef USE_SIGNALS
1883 		case 'k':
1884 			sig = SIGALRM;
1885 			siga = "ALRM";
1886 			break;
1887 		case 'n':
1888 			sig = SIGHUP;
1889 			siga = "HUP";
1890 			break;
1891 		case 'g':
1892 		case 'p':
1893 			/* Force going via command socket as we're
1894 			 * out of user definable signals. */
1895 			i = 4;
1896 			break;
1897 		case 'q':
1898 			/* -qq disables console output entirely.
1899 			 * This is important for systemd because it logs
1900 			 * both console AND syslog to the same log
1901 			 * resulting in untold confusion. */
1902 			if (logopts & LOGERR_QUIET)
1903 				logopts &= ~LOGERR_ERR;
1904 			else
1905 				logopts |= LOGERR_QUIET;
1906 			break;
1907 		case 'x':
1908 			sig = SIGTERM;
1909 			siga = "TERM";
1910 			break;
1911 		case 'N':
1912 			sig = SIGUSR1;
1913 			siga = "USR1";
1914 			break;
1915 #endif
1916 		case 'P':
1917 			ctx.options |= DHCPCD_PRINT_PIDFILE;
1918 			logopts &= ~(LOGERR_LOG | LOGERR_ERR);
1919 			break;
1920 		case 'T':
1921 			i = 1;
1922 			logopts &= ~LOGERR_LOG;
1923 			break;
1924 		case 'U':
1925 			i = 3;
1926 			break;
1927 		case 'V':
1928 			i = 2;
1929 			break;
1930 		case '?':
1931 			if (ctx.options & DHCPCD_PRINT_PIDFILE)
1932 				continue;
1933 			usage();
1934 			goto exit_failure;
1935 		}
1936 	}
1937 
1938 	logsetopts(logopts);
1939 	logopen(ctx.logfile);
1940 
1941 	ctx.argv = argv;
1942 	ctx.argc = argc;
1943 	ctx.ifc = argc - optind;
1944 	ctx.ifv = argv + optind;
1945 
1946 	ifo = read_config(&ctx, NULL, NULL, NULL);
1947 	if (ifo == NULL) {
1948 		if (ctx.options & DHCPCD_PRINT_PIDFILE)
1949 			goto printpidfile;
1950 		goto exit_failure;
1951 	}
1952 	opt = add_options(&ctx, NULL, ifo, argc, argv);
1953 	if (opt != 1) {
1954 		if (ctx.options & DHCPCD_PRINT_PIDFILE)
1955 			goto printpidfile;
1956 		if (opt == 0)
1957 			usage();
1958 		goto exit_failure;
1959 	}
1960 	if (i == 2) {
1961 		printf("Interface options:\n");
1962 		if (optind == argc - 1) {
1963 			free_options(&ctx, ifo);
1964 			ifo = read_config(&ctx, argv[optind], NULL, NULL);
1965 			if (ifo == NULL)
1966 				goto exit_failure;
1967 			add_options(&ctx, NULL, ifo, argc, argv);
1968 		}
1969 		if_printoptions();
1970 #ifdef INET
1971 		if (family == 0 || family == AF_INET) {
1972 			printf("\nDHCPv4 options:\n");
1973 			dhcp_printoptions(&ctx,
1974 			    ifo->dhcp_override, ifo->dhcp_override_len);
1975 		}
1976 #endif
1977 #ifdef INET6
1978 		if (family == 0 || family == AF_INET6) {
1979 			printf("\nND options:\n");
1980 			ipv6nd_printoptions(&ctx,
1981 			    ifo->nd_override, ifo->nd_override_len);
1982 #ifdef DHCP6
1983 			printf("\nDHCPv6 options:\n");
1984 			dhcp6_printoptions(&ctx,
1985 			    ifo->dhcp6_override, ifo->dhcp6_override_len);
1986 #endif
1987 		}
1988 #endif
1989 		goto exit_success;
1990 	}
1991 	ctx.options |= ifo->options;
1992 	if (i == 1 || i == 3) {
1993 		if (i == 1)
1994 			ctx.options |= DHCPCD_TEST;
1995 		else
1996 			ctx.options |= DHCPCD_DUMPLEASE;
1997 		ctx.options |= DHCPCD_PERSISTENT;
1998 		ctx.options &= ~DHCPCD_DAEMONISE;
1999 	}
2000 
2001 #ifdef THERE_IS_NO_FORK
2002 	ctx.options &= ~DHCPCD_DAEMONISE;
2003 #endif
2004 
2005 	if (ctx.options & DHCPCD_DEBUG)
2006 		logsetopts(logopts | LOGERR_DEBUG);
2007 
2008 	if (!(ctx.options & (DHCPCD_TEST | DHCPCD_DUMPLEASE))) {
2009 printpidfile:
2010 		/* If we have any other args, we should run as a single dhcpcd
2011 		 *  instance for that interface. */
2012 		if (optind == argc - 1 && !(ctx.options & DHCPCD_MASTER)) {
2013 			const char *per;
2014 			const char *ifname;
2015 
2016 			ifname = *ctx.ifv;
2017 			if (ifname == NULL || strlen(ifname) > IF_NAMESIZE) {
2018 				errno = ifname == NULL ? EINVAL : E2BIG;
2019 				logerr("%s: ", ifname);
2020 				goto exit_failure;
2021 			}
2022 			/* Allow a dhcpcd interface per address family */
2023 			switch(family) {
2024 			case AF_INET:
2025 				per = "-4";
2026 				break;
2027 			case AF_INET6:
2028 				per = "-6";
2029 				break;
2030 			default:
2031 				per = "";
2032 			}
2033 			snprintf(ctx.pidfile, sizeof(ctx.pidfile),
2034 			    PIDFILE, ifname, per, ".");
2035 		} else {
2036 			snprintf(ctx.pidfile, sizeof(ctx.pidfile),
2037 			    PIDFILE, "", "", "");
2038 			ctx.options |= DHCPCD_MASTER;
2039 		}
2040 		if (ctx.options & DHCPCD_PRINT_PIDFILE) {
2041 			printf("%s\n", ctx.pidfile);
2042 			goto exit_success;
2043 		}
2044 	}
2045 
2046 	if (chdir("/") == -1)
2047 		logerr("%s: chdir `/'", __func__);
2048 
2049 	/* Freeing allocated addresses from dumping leases can trigger
2050 	 * eloop removals as well, so init here. */
2051 	if ((ctx.eloop = eloop_new()) == NULL) {
2052 		logerr("%s: eloop_init", __func__);
2053 		goto exit_failure;
2054 	}
2055 
2056 #ifdef USE_SIGNALS
2057 	for (si = 0; si < dhcpcd_signals_ignore_len; si++)
2058 		signal(dhcpcd_signals_ignore[si], SIG_IGN);
2059 
2060 	/* Save signal mask, block and redirect signals to our handler */
2061 	eloop_signal_set_cb(ctx.eloop,
2062 	    dhcpcd_signals, dhcpcd_signals_len,
2063 	    dhcpcd_signal_cb, &ctx);
2064 	if (eloop_signal_mask(ctx.eloop, &ctx.sigset) == -1) {
2065 		logerr("%s: eloop_signal_mask", __func__);
2066 		goto exit_failure;
2067 	}
2068 
2069 	if (sig != 0) {
2070 		pid = pidfile_read(ctx.pidfile);
2071 		if (pid != 0 && pid != -1)
2072 			loginfox("sending signal %s to pid %d", siga, pid);
2073 		if (pid == 0 || pid == -1 || kill(pid, sig) != 0) {
2074 			if (sig != SIGHUP && sig != SIGUSR1 && errno != EPERM)
2075 				logerrx(PACKAGE" not running");
2076 			if (pid != 0 && pid != -1 && errno != ESRCH) {
2077 				logerr("kill");
2078 				goto exit_failure;
2079 			}
2080 			unlink(ctx.pidfile);
2081 			if (sig != SIGHUP && sig != SIGUSR1)
2082 				goto exit_failure;
2083 		} else {
2084 			struct timespec ts;
2085 
2086 			if (sig == SIGHUP || sig == SIGUSR1)
2087 				goto exit_success;
2088 			/* Spin until it exits */
2089 			loginfox("waiting for pid %d to exit", pid);
2090 			ts.tv_sec = 0;
2091 			ts.tv_nsec = 100000000; /* 10th of a second */
2092 			for(i = 0; i < 100; i++) {
2093 				nanosleep(&ts, NULL);
2094 				if (pidfile_read(ctx.pidfile) == -1)
2095 					goto exit_success;
2096 			}
2097 			logerrx("pid %d failed to exit", pid);
2098 			goto exit_failure;
2099 		}
2100 	}
2101 #endif
2102 
2103 #ifndef SMALL
2104 	if (ctx.options & DHCPCD_DUMPLEASE &&
2105 	    ioctl(fileno(stdin), FIONREAD, &i, sizeof(i)) == 0 &&
2106 	    i > 0)
2107 	{
2108 		ifp = calloc(1, sizeof(*ifp));
2109 		if (ifp == NULL) {
2110 			logerr(__func__);
2111 			goto exit_failure;
2112 		}
2113 		ifp->ctx = &ctx;
2114 		ifp->options = ifo;
2115 		switch (family) {
2116 		case AF_INET:
2117 #ifdef INET
2118 			if (dhcp_dump(ifp) == -1)
2119 				goto exit_failure;
2120 			break;
2121 #else
2122 			logerrx("No DHCP support");
2123 			goto exit_failure;
2124 #endif
2125 		case AF_INET6:
2126 #ifdef DHCP6
2127 			if (dhcp6_dump(ifp) == -1)
2128 				goto exit_failure;
2129 			break;
2130 #else
2131 			logerrx("No DHCP6 support");
2132 			goto exit_failure;
2133 #endif
2134 		default:
2135 			logerrx("Family not specified. Please use -4 or -6.");
2136 			goto exit_failure;
2137 		}
2138 		goto exit_success;
2139 	}
2140 #endif
2141 
2142 	/* Test against siga instead of sig to avoid gcc
2143 	 * warning about a bogus potential signed overflow.
2144 	 * The end result will be the same. */
2145 	if ((siga == NULL || i == 4 || ctx.ifc != 0) &&
2146 	    !(ctx.options & DHCPCD_TEST))
2147 	{
2148 		ctx.options |= DHCPCD_FORKED; /* avoid socket unlink */
2149 		if (!(ctx.options & DHCPCD_MASTER))
2150 			ctx.control_fd = control_open(argv[optind], family,
2151 			    ctx.options & DHCPCD_DUMPLEASE);
2152 		if (ctx.control_fd == -1)
2153 			ctx.control_fd = control_open(NULL, AF_UNSPEC,
2154 			    ctx.options & DHCPCD_DUMPLEASE);
2155 		if (ctx.control_fd != -1) {
2156 			if (!(ctx.options & DHCPCD_DUMPLEASE))
2157 				loginfox("sending commands to dhcpcd process");
2158 			len = control_send(&ctx, argc, argv);
2159 			if (len > 0)
2160 				logdebugx("send OK");
2161 			else {
2162 				logerr("%s: control_send", __func__);
2163 				goto exit_failure;
2164 			}
2165 			if (ctx.options & DHCPCD_DUMPLEASE) {
2166 				if (dhcpcd_readdump(&ctx) == -1) {
2167 					logerr("%s: dhcpcd_readdump", __func__);
2168 					goto exit_failure;
2169 				}
2170 				goto run_loop;
2171 			}
2172 			goto exit_success;
2173 		} else {
2174 			if (errno != ENOENT)
2175 				logerr("%s: control_open", __func__);
2176 			if (ctx.options & DHCPCD_DUMPLEASE) {
2177 				if (errno == ENOENT)
2178 					logerrx("dhcpcd is not running");
2179 				goto exit_failure;
2180 			}
2181 			if (errno == EPERM || errno == EACCES)
2182 				goto exit_failure;
2183 		}
2184 		ctx.options &= ~DHCPCD_FORKED;
2185 	}
2186 
2187 	if (!(ctx.options & DHCPCD_TEST)) {
2188 		/* Ensure we have the needed directories */
2189 		if (mkdir(RUNDIR, 0755) == -1 && errno != EEXIST)
2190 			logerr("%s: mkdir `%s'", __func__, RUNDIR);
2191 		if ((pid = pidfile_lock(ctx.pidfile)) != 0) {
2192 			if (pid == -1)
2193 				logerr("%s: pidfile_lock: %s",
2194 				    __func__, ctx.pidfile);
2195 			else
2196 				logerrx(PACKAGE
2197 				    " already running on pid %d (%s)",
2198 				    pid, ctx.pidfile);
2199 			goto exit_failure;
2200 		}
2201 	}
2202 
2203 	loginfox(PACKAGE "-" VERSION " starting");
2204 	if (freopen(_PATH_DEVNULL, "r", stdin) == NULL)
2205 		logerr("%s: freopen stdin", __func__);
2206 
2207 
2208 #ifdef PRIVSEP
2209 	ps_init(&ctx);
2210 #endif
2211 
2212 #ifdef USE_SIGNALS
2213 	if (pipe(sigpipe) == -1) {
2214 		logerr("pipe");
2215 		goto exit_failure;
2216 	}
2217 #ifdef HAVE_CAPSICUM
2218 	if (ps_rights_limit_fdpair(sigpipe) == -1) {
2219 		logerr("ps_rights_limit_fdpair");
2220 		goto exit_failure;
2221 	}
2222 #endif
2223 	switch (pid = fork()) {
2224 	case -1:
2225 		logerr("fork");
2226 		goto exit_failure;
2227 	case 0:
2228 		ctx.fork_fd = sigpipe[1];
2229 		close(sigpipe[0]);
2230 		if (setsid() == -1) {
2231 			logerr("%s: setsid", __func__);
2232 			goto exit_failure;
2233 		}
2234 		/* Ensure we can never get a controlling terminal */
2235 		switch (pid = fork()) {
2236 		case -1:
2237 			logerr("fork");
2238 			goto exit_failure;
2239 		case 0:
2240 			break;
2241 		default:
2242 			ctx.options |= DHCPCD_FORKED; /* A lie */
2243 			i = EXIT_SUCCESS;
2244 			goto exit1;
2245 		}
2246 		break;
2247 	default:
2248 		ctx.options |= DHCPCD_FORKED; /* A lie */
2249 		ctx.fork_fd = sigpipe[0];
2250 		close(sigpipe[1]);
2251 		setproctitle("[launcher]");
2252 		eloop_event_add(ctx.eloop, ctx.fork_fd, dhcpcd_fork_cb, &ctx);
2253 		goto run_loop;
2254 	}
2255 
2256 	/* We have now forked, setsid, forked once more.
2257 	 * From this point on, we are the controlling daemon. */
2258 	ctx.options |= DHCPCD_STARTED;
2259 	if ((pid = pidfile_lock(ctx.pidfile)) != 0) {
2260 		logerr("%s: pidfile_lock %d", __func__, pid);
2261 		goto exit_failure;
2262 	}
2263 #endif
2264 
2265 #if defined(BSD) && defined(INET6)
2266 	/* Disable the kernel RTADV sysctl as early as possible. */
2267 	if (ctx.options & DHCPCD_IPV6 && ctx.options & DHCPCD_IPV6RS)
2268 		if_disable_rtadv();
2269 #endif
2270 
2271 	if (isatty(STDOUT_FILENO) &&
2272 	    freopen(_PATH_DEVNULL, "r", stdout) == NULL)
2273 		logerr("%s: freopen stdout", __func__);
2274 	if (isatty(STDERR_FILENO)) {
2275 		int fd = dup(STDERR_FILENO);
2276 
2277 		if (fd == -1)
2278 			logerr("%s: dup", __func__);
2279 		else if (logseterrfd(fd) == -1)
2280 			logerr("%s: logseterrfd", __func__);
2281 		else if (freopen(_PATH_DEVNULL, "r", stderr) == NULL) {
2282 			logseterrfd(-1);
2283 			logerr("%s: freopen stderr", __func__);
2284 		}
2285 	}
2286 
2287 	/* If we're not running in privsep, we need to create the DB
2288 	 * directory here. */
2289 	if (!(ctx.options & DHCPCD_PRIVSEP)) {
2290 		if (mkdir(DBDIR, 0755) == -1 && errno != EEXIST)
2291 			logerr("%s: mkdir `%s'", __func__, DBDIR);
2292 	}
2293 
2294 #ifdef PRIVSEP
2295 	if (IN_PRIVSEP(&ctx) && ps_start(&ctx) == -1) {
2296 		logerr("ps_start");
2297 		goto exit_failure;
2298 	}
2299 	if (ctx.options & DHCPCD_FORKED)
2300 		goto run_loop;
2301 #endif
2302 
2303 	if (!(ctx.options & DHCPCD_TEST)) {
2304 		if (control_start(&ctx,
2305 		    ctx.options & DHCPCD_MASTER ?
2306 		    NULL : argv[optind], family) == -1)
2307 		{
2308 			logerr("%s: control_start", __func__);
2309 			goto exit_failure;
2310 		}
2311 	}
2312 
2313 #ifdef PLUGIN_DEV
2314 	/* Start any dev listening plugin which may want to
2315 	 * change the interface name provided by the kernel */
2316 	if (!IN_PRIVSEP(&ctx) &&
2317 	    (ctx.options & (DHCPCD_MASTER | DHCPCD_DEV)) ==
2318 	    (DHCPCD_MASTER | DHCPCD_DEV))
2319 		dev_start(&ctx, dhcpcd_handleinterface);
2320 #endif
2321 
2322 	setproctitle("%s%s%s",
2323 	    ctx.options & DHCPCD_MASTER ? "[master]" : argv[optind],
2324 	    ctx.options & DHCPCD_IPV4 ? " [ip4]" : "",
2325 	    ctx.options & DHCPCD_IPV6 ? " [ip6]" : "");
2326 
2327 	if (if_opensockets(&ctx) == -1) {
2328 		logerr("%s: if_opensockets", __func__);
2329 		goto exit_failure;
2330 	}
2331 #ifndef SMALL
2332 	dhcpcd_setlinkrcvbuf(&ctx);
2333 #endif
2334 
2335 	/* Try and create DUID from the machine UUID. */
2336 	dhcpcd_initduid(&ctx, NULL);
2337 
2338 	/* Cache the default vendor option. */
2339 	if (dhcp_vendor(ctx.vendor, sizeof(ctx.vendor)) == -1)
2340 		logerr("dhcp_vendor");
2341 
2342 	/* Start handling kernel messages for interfaces, addresses and
2343 	 * routes. */
2344 	eloop_event_add(ctx.eloop, ctx.link_fd, dhcpcd_handlelink, &ctx);
2345 
2346 #ifdef PRIVSEP
2347 	if (IN_PRIVSEP(&ctx) && ps_mastersandbox(&ctx) == -1)
2348 		goto exit_failure;
2349 #endif
2350 
2351 	/* When running dhcpcd against a single interface, we need to retain
2352 	 * the old behaviour of waiting for an IP address */
2353 	if (ctx.ifc == 1 && !(ctx.options & DHCPCD_BACKGROUND))
2354 		ctx.options |= DHCPCD_WAITIP;
2355 
2356 	ctx.ifaces = if_discover(&ctx, &ifaddrs, ctx.ifc, ctx.ifv);
2357 	if (ctx.ifaces == NULL) {
2358 		logerr("%s: if_discover", __func__);
2359 		goto exit_failure;
2360 	}
2361 	for (i = 0; i < ctx.ifc; i++) {
2362 		if ((ifp = if_find(ctx.ifaces, ctx.ifv[i])) == NULL)
2363 			logerrx("%s: interface not found",
2364 			    ctx.ifv[i]);
2365 		else if (!ifp->active)
2366 			logerrx("%s: interface has an invalid configuration",
2367 			    ctx.ifv[i]);
2368 	}
2369 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2370 		if (ifp->active == IF_ACTIVE_USER)
2371 			break;
2372 	}
2373 	if (ifp == NULL) {
2374 		if (ctx.ifc == 0) {
2375 			int loglevel;
2376 
2377 			loglevel = ctx.options & DHCPCD_INACTIVE ?
2378 			    LOG_DEBUG : LOG_ERR;
2379 			logmessage(loglevel, "no valid interfaces found");
2380 			dhcpcd_daemonise(&ctx);
2381 		} else
2382 			goto exit_failure;
2383 		if (!(ctx.options & DHCPCD_LINK)) {
2384 			logerrx("aborting as link detection is disabled");
2385 			goto exit_failure;
2386 		}
2387 	}
2388 
2389 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2390 		if (ifp->active)
2391 			dhcpcd_initstate1(ifp, argc, argv, 0);
2392 	}
2393 	if_learnaddrs(&ctx, ctx.ifaces, &ifaddrs);
2394 
2395 	if (ctx.options & DHCPCD_BACKGROUND)
2396 		dhcpcd_daemonise(&ctx);
2397 
2398 	opt = 0;
2399 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2400 		if (ifp->active) {
2401 			run_preinit(ifp);
2402 			if (!(ifp->options->options & DHCPCD_LINK) ||
2403 			    ifp->carrier != LINK_DOWN)
2404 				opt = 1;
2405 		}
2406 	}
2407 
2408 	if (!(ctx.options & DHCPCD_BACKGROUND)) {
2409 		if (ctx.options & DHCPCD_MASTER)
2410 			t = ifo->timeout;
2411 		else {
2412 			t = 0;
2413 			TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2414 				if (ifp->active) {
2415 					t = ifp->options->timeout;
2416 					break;
2417 				}
2418 			}
2419 		}
2420 		if (opt == 0 &&
2421 		    ctx.options & DHCPCD_LINK &&
2422 		    !(ctx.options & DHCPCD_WAITIP))
2423 		{
2424 			int loglevel;
2425 
2426 			loglevel = ctx.options & DHCPCD_INACTIVE ?
2427 			    LOG_DEBUG : LOG_WARNING;
2428 			logmessage(loglevel, "no interfaces have a carrier");
2429 			dhcpcd_daemonise(&ctx);
2430 		} else if (t > 0 &&
2431 		    /* Test mode removes the daemonise bit, so check for both */
2432 		    ctx.options & (DHCPCD_DAEMONISE | DHCPCD_TEST))
2433 		{
2434 			eloop_timeout_add_sec(ctx.eloop, t,
2435 			    handle_exit_timeout, &ctx);
2436 		}
2437 	}
2438 	free_options(&ctx, ifo);
2439 	ifo = NULL;
2440 
2441 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2442 		if (ifp->active)
2443 			eloop_timeout_add_sec(ctx.eloop, 0,
2444 			    dhcpcd_prestartinterface, ifp);
2445 	}
2446 
2447 run_loop:
2448 	i = eloop_start(ctx.eloop, &ctx.sigset);
2449 	if (i < 0) {
2450 		logerr("%s: eloop_start", __func__);
2451 		goto exit_failure;
2452 	}
2453 	goto exit1;
2454 
2455 exit_success:
2456 	i = EXIT_SUCCESS;
2457 	goto exit1;
2458 
2459 exit_failure:
2460 	i = EXIT_FAILURE;
2461 
2462 exit1:
2463 	if (control_stop(&ctx) == -1)
2464 		logerr("%s: control_stop", __func__);
2465 	if (ifaddrs != NULL) {
2466 #ifdef PRIVSEP_GETIFADDRS
2467 		if (IN_PRIVSEP(&ctx))
2468 			free(ifaddrs);
2469 		else
2470 #endif
2471 			freeifaddrs(ifaddrs);
2472 	}
2473 #ifdef PRIVSEP
2474 	ps_stop(&ctx);
2475 #endif
2476 	/* Free memory and close fd's */
2477 	if (ctx.ifaces) {
2478 		while ((ifp = TAILQ_FIRST(ctx.ifaces))) {
2479 			TAILQ_REMOVE(ctx.ifaces, ifp, next);
2480 			if_free(ifp);
2481 		}
2482 		free(ctx.ifaces);
2483 		ctx.ifaces = NULL;
2484 	}
2485 	free_options(&ctx, ifo);
2486 #ifdef HAVE_OPEN_MEMSTREAM
2487 	if (ctx.script_fp)
2488 		fclose(ctx.script_fp);
2489 #endif
2490 	free(ctx.script_buf);
2491 	free(ctx.script_env);
2492 	rt_dispose(&ctx);
2493 	free(ctx.duid);
2494 	if (ctx.link_fd != -1) {
2495 		eloop_event_delete(ctx.eloop, ctx.link_fd);
2496 		close(ctx.link_fd);
2497 	}
2498 	if_closesockets(&ctx);
2499 	free_globals(&ctx);
2500 #ifdef INET6
2501 	ipv6_ctxfree(&ctx);
2502 #endif
2503 #ifdef PLUGIN_DEV
2504 	dev_stop(&ctx);
2505 #endif
2506 #ifdef PRIVSEP
2507 	eloop_free(ctx.ps_eloop);
2508 #endif
2509 	eloop_free(ctx.eloop);
2510 	if (ctx.script != dhcpcd_default_script)
2511 		free(ctx.script);
2512 	if (ctx.options & DHCPCD_STARTED && !(ctx.options & DHCPCD_FORKED))
2513 		loginfox(PACKAGE " exited");
2514 	logclose();
2515 	free(ctx.logfile);
2516 	free(ctx.ctl_buf);
2517 #ifdef SETPROCTITLE_H
2518 	setproctitle_free();
2519 #endif
2520 #ifdef USE_SIGNALS
2521 	if (ctx.options & DHCPCD_FORKED)
2522 		_exit(i); /* so atexit won't remove our pidfile */
2523 	else if (ctx.options & DHCPCD_STARTED) {
2524 		/* Try to detach from the launch process. */
2525 		if (ctx.fork_fd != -1 &&
2526 		    write(ctx.fork_fd, &i, sizeof(i)) == -1)
2527 			logerr("%s: write", __func__);
2528 	}
2529 #endif
2530 	return i;
2531 }
2532