xref: /dragonfly/contrib/dhcpcd/src/dhcpcd.c (revision 54175cef)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * dhcpcd - DHCP client daemon
4  * Copyright (c) 2006-2023 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 static const char dhcpcd_copyright[] = "Copyright (c) 2006-2023 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_OPENSSL
79 #include <openssl/crypto.h>
80 #endif
81 #ifdef HAVE_UTIL_H
82 #include <util.h>
83 #endif
84 
85 #ifdef USE_SIGNALS
86 const int dhcpcd_signals[] = {
87 	SIGTERM,
88 	SIGINT,
89 	SIGALRM,
90 	SIGHUP,
91 	SIGUSR1,
92 	SIGUSR2,
93 	SIGCHLD,
94 };
95 const size_t dhcpcd_signals_len = __arraycount(dhcpcd_signals);
96 
97 const int dhcpcd_signals_ignore[] = {
98 	SIGPIPE,
99 };
100 const size_t dhcpcd_signals_ignore_len = __arraycount(dhcpcd_signals_ignore);
101 #endif
102 
103 const char *dhcpcd_default_script = SCRIPT;
104 
105 static void
usage(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
free_globals(struct dhcpcd_ctx * ctx)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
handle_exit_timeout(void * arg)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_MANAGER)) {
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 *
dhcpcd_af(int af)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
dhcpcd_ifafwaiting(const struct interface * ifp)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_INET6;
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
dhcpcd_afwaiting(const struct dhcpcd_ctx * ctx)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
dhcpcd_ipwaited(struct dhcpcd_ctx * ctx)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 #ifndef THERE_IS_NO_FORK
333 void
dhcpcd_daemonised(struct dhcpcd_ctx * ctx)334 dhcpcd_daemonised(struct dhcpcd_ctx *ctx)
335 {
336 	unsigned int logopts = loggetopts();
337 
338 	/*
339 	 * Stop writing to stderr.
340 	 * On the happy path, only the manager process writes to stderr,
341 	 * so this just stops wasting fprintf calls to nowhere.
342 	 */
343 	logopts &= ~LOGERR_ERR;
344 	logsetopts(logopts);
345 
346 	/*
347 	 * We need to do something with stdout/stderr to avoid SIGPIPE.
348 	 * We know that stdin is already mapped to /dev/null.
349 	 * TODO: Capture script output and log it to the logfile and/or syslog.
350 	 */
351 	dup2(STDIN_FILENO, STDOUT_FILENO);
352 	dup2(STDIN_FILENO, STDERR_FILENO);
353 
354 	ctx->options |= DHCPCD_DAEMONISED;
355 }
356 #endif
357 
358 /* Returns the pid of the child, otherwise 0. */
359 void
dhcpcd_daemonise(struct dhcpcd_ctx * ctx)360 dhcpcd_daemonise(struct dhcpcd_ctx *ctx)
361 {
362 #ifdef THERE_IS_NO_FORK
363 	eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx);
364 	errno = ENOSYS;
365 	return;
366 #else
367 	int exit_code;
368 
369 	if (ctx->options & DHCPCD_DAEMONISE &&
370 	    !(ctx->options & (DHCPCD_DAEMONISED | DHCPCD_NOWAITIP)))
371 	{
372 		if (!dhcpcd_ipwaited(ctx))
373 			return;
374 	}
375 
376 	if (ctx->options & DHCPCD_ONESHOT) {
377 		loginfox("exiting due to oneshot");
378 		eloop_exit(ctx->eloop, EXIT_SUCCESS);
379 		return;
380 	}
381 
382 	eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx);
383 	if (ctx->options & DHCPCD_DAEMONISED ||
384 	    !(ctx->options & DHCPCD_DAEMONISE))
385 		return;
386 
387 #ifdef PRIVSEP
388 	if (IN_PRIVSEP(ctx))
389 		ps_daemonised(ctx);
390 	else
391 #endif
392 		dhcpcd_daemonised(ctx);
393 
394 	eloop_event_delete(ctx->eloop, ctx->fork_fd);
395 	exit_code = EXIT_SUCCESS;
396 	if (write(ctx->fork_fd, &exit_code, sizeof(exit_code)) == -1)
397 		logerr(__func__);
398 	close(ctx->fork_fd);
399 	ctx->fork_fd = -1;
400 #endif
401 }
402 
403 static void
dhcpcd_drop_af(struct interface * ifp,int stop,int af)404 dhcpcd_drop_af(struct interface *ifp, int stop, int af)
405 {
406 
407 	if (af == AF_UNSPEC || af == AF_INET6) {
408 #ifdef DHCP6
409 		dhcp6_drop(ifp, stop ? NULL : "EXPIRE6");
410 #endif
411 #ifdef INET6
412 		ipv6nd_drop(ifp);
413 		ipv6_drop(ifp);
414 #endif
415 	}
416 
417 	if (af == AF_UNSPEC || af == AF_INET) {
418 #ifdef IPV4LL
419 		ipv4ll_drop(ifp);
420 #endif
421 #ifdef INET
422 		dhcp_drop(ifp, stop ? "STOP" : "EXPIRE");
423 #endif
424 #ifdef ARP
425 		arp_drop(ifp);
426 	}
427 #endif
428 
429 #if !defined(DHCP6) && !defined(DHCP)
430 	UNUSED(stop);
431 #endif
432 }
433 
434 static void
dhcpcd_drop(struct interface * ifp,int stop)435 dhcpcd_drop(struct interface *ifp, int stop)
436 {
437 
438 	dhcpcd_drop_af(ifp, stop, AF_UNSPEC);
439 }
440 
441 static void
stop_interface(struct interface * ifp,const char * reason)442 stop_interface(struct interface *ifp, const char *reason)
443 {
444 	struct dhcpcd_ctx *ctx;
445 
446 	ctx = ifp->ctx;
447 	loginfox("%s: removing interface", ifp->name);
448 	ifp->options->options |= DHCPCD_STOPPING;
449 
450 	dhcpcd_drop(ifp, 1);
451 	script_runreason(ifp, reason == NULL ? "STOPPED" : reason);
452 
453 	/* Delete all timeouts for the interfaces */
454 	eloop_q_timeout_delete(ctx->eloop, ELOOP_QUEUE_ALL, NULL, ifp);
455 
456 	/* De-activate the interface */
457 	ifp->active = IF_INACTIVE;
458 	ifp->options->options &= ~DHCPCD_STOPPING;
459 
460 	if (!(ctx->options & (DHCPCD_MANAGER | DHCPCD_TEST)))
461 		eloop_exit(ctx->eloop, EXIT_FAILURE);
462 }
463 
464 static void
configure_interface1(struct interface * ifp)465 configure_interface1(struct interface *ifp)
466 {
467 	struct if_options *ifo = ifp->options;
468 
469 	/* Do any platform specific configuration */
470 	if_conf(ifp);
471 
472 	/* If we want to release a lease, we can't really persist the
473 	 * address either. */
474 	if (ifo->options & DHCPCD_RELEASE)
475 		ifo->options &= ~DHCPCD_PERSISTENT;
476 
477 	if (ifp->flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) {
478 		ifo->options &= ~DHCPCD_ARP;
479 		if (!(ifp->flags & IFF_MULTICAST))
480 			ifo->options &= ~DHCPCD_IPV6RS;
481 		if (!(ifo->options & (DHCPCD_INFORM | DHCPCD_WANTDHCP)))
482 			ifo->options |= DHCPCD_STATIC;
483 	}
484 
485 	if (ifo->metric != -1)
486 		ifp->metric = (unsigned int)ifo->metric;
487 
488 #ifdef INET6
489 	/* We want to setup INET6 on the interface as soon as possible. */
490 	if (ifp->active == IF_ACTIVE_USER &&
491 	    ifo->options & DHCPCD_IPV6 &&
492 	    !(ifp->ctx->options & (DHCPCD_DUMPLEASE | DHCPCD_TEST)))
493 	{
494 		/* If not doing any DHCP, disable the RDNSS requirement. */
495 		if (!(ifo->options & (DHCPCD_DHCP | DHCPCD_DHCP6)))
496 			ifo->options &= ~DHCPCD_IPV6RA_REQRDNSS;
497 		if_setup_inet6(ifp);
498 	}
499 #endif
500 
501 	if (!(ifo->options & DHCPCD_IAID)) {
502 		/*
503 		 * An IAID is for identifying a unqiue interface within
504 		 * the client. It is 4 bytes long. Working out a default
505 		 * value is problematic.
506 		 *
507 		 * Interface name and number are not stable
508 		 * between different OS's. Some OS's also cannot make
509 		 * up their mind what the interface should be called
510 		 * (yes, udev, I'm looking at you).
511 		 * Also, the name could be longer than 4 bytes.
512 		 * Also, with pluggable interfaces the name and index
513 		 * could easily get swapped per actual interface.
514 		 *
515 		 * The MAC address is 6 bytes long, the final 3
516 		 * being unique to the manufacturer and the initial 3
517 		 * being unique to the organisation which makes it.
518 		 * We could use the last 4 bytes of the MAC address
519 		 * as the IAID as it's the most stable part given the
520 		 * above, but equally it's not guaranteed to be
521 		 * unique.
522 		 *
523 		 * Given the above, and our need to reliably work
524 		 * between reboots without persitent storage,
525 		 * generating the IAID from the MAC address is the only
526 		 * logical default.
527 		 * Saying that, if a VLANID has been specified then we
528 		 * can use that. It's possible that different interfaces
529 		 * can have the same VLANID, but this is no worse than
530 		 * generating the IAID from the duplicate MAC address.
531 		 *
532 		 * dhclient uses the last 4 bytes of the MAC address.
533 		 * dibbler uses an increamenting counter.
534 		 * wide-dhcpv6 uses 0 or a configured value.
535 		 * odhcp6c uses 1.
536 		 * Windows 7 uses the first 3 bytes of the MAC address
537 		 * and an unknown byte.
538 		 * dhcpcd-6.1.0 and earlier used the interface name,
539 		 * falling back to interface index if name > 4.
540 		 */
541 		if (ifp->vlanid != 0) {
542 			uint32_t vlanid;
543 
544 			/* Maximal VLANID is 4095, so prefix with 0xff
545 			 * so we don't conflict with an interface index. */
546 			vlanid = htonl(ifp->vlanid | 0xff000000);
547 			memcpy(ifo->iaid, &vlanid, sizeof(vlanid));
548 		} else if (ifo->options & DHCPCD_ANONYMOUS)
549 			memset(ifo->iaid, 0, sizeof(ifo->iaid));
550 		else if (ifp->hwlen >= sizeof(ifo->iaid)) {
551 			memcpy(ifo->iaid,
552 			    ifp->hwaddr + ifp->hwlen - sizeof(ifo->iaid),
553 			    sizeof(ifo->iaid));
554 		} else {
555 			uint32_t len;
556 
557 			len = (uint32_t)strlen(ifp->name);
558 			if (len <= sizeof(ifo->iaid)) {
559 				memcpy(ifo->iaid, ifp->name, len);
560 				if (len < sizeof(ifo->iaid))
561 					memset(ifo->iaid + len, 0,
562 					    sizeof(ifo->iaid) - len);
563 			} else {
564 				/* IAID is the same size as a uint32_t */
565 				len = htonl(ifp->index);
566 				memcpy(ifo->iaid, &len, sizeof(ifo->iaid));
567 			}
568 		}
569 		ifo->options |= DHCPCD_IAID;
570 	}
571 
572 #ifdef DHCP6
573 	if (ifo->ia_len == 0 && ifo->options & DHCPCD_IPV6 &&
574 	    ifp->name[0] != '\0')
575 	{
576 		ifo->ia = malloc(sizeof(*ifo->ia));
577 		if (ifo->ia == NULL)
578 			logerr(__func__);
579 		else {
580 			ifo->ia_len = 1;
581 			ifo->ia->ia_type = D6_OPTION_IA_NA;
582 			memcpy(ifo->ia->iaid, ifo->iaid, sizeof(ifo->iaid));
583 			memset(&ifo->ia->addr, 0, sizeof(ifo->ia->addr));
584 #ifndef SMALL
585 			ifo->ia->sla = NULL;
586 			ifo->ia->sla_len = 0;
587 #endif
588 		}
589 	} else {
590 		size_t i;
591 
592 		for (i = 0; i < ifo->ia_len; i++) {
593 			if (!ifo->ia[i].iaid_set) {
594 				memcpy(&ifo->ia[i].iaid, ifo->iaid,
595 				    sizeof(ifo->ia[i].iaid));
596 				ifo->ia[i].iaid_set = 1;
597 			}
598 		}
599 	}
600 #endif
601 
602 	/* If root is network mounted, we don't want to kill the connection
603 	 * if the DHCP server goes the way of the dodo OR dhcpcd is rebooting
604 	 * and the lease file has expired. */
605 	if (is_root_local() == 0)
606 		ifo->options |= DHCPCD_LASTLEASE_EXTEND;
607 }
608 
609 int
dhcpcd_selectprofile(struct interface * ifp,const char * profile)610 dhcpcd_selectprofile(struct interface *ifp, const char *profile)
611 {
612 	struct if_options *ifo;
613 	char pssid[PROFILE_LEN];
614 
615 	if (ifp->ssid_len) {
616 		ssize_t r;
617 
618 		r = print_string(pssid, sizeof(pssid), OT_ESCSTRING,
619 		    ifp->ssid, ifp->ssid_len);
620 		if (r == -1) {
621 			logerr(__func__);
622 			pssid[0] = '\0';
623 		}
624 	} else
625 		pssid[0] = '\0';
626 	ifo = read_config(ifp->ctx, ifp->name, pssid, profile);
627 	if (ifo == NULL) {
628 		logdebugx("%s: no profile %s", ifp->name, profile);
629 		return -1;
630 	}
631 	if (profile != NULL) {
632 		strlcpy(ifp->profile, profile, sizeof(ifp->profile));
633 		loginfox("%s: selected profile %s", ifp->name, profile);
634 	} else
635 		*ifp->profile = '\0';
636 
637 	free_options(ifp->ctx, ifp->options);
638 	ifp->options = ifo;
639 	if (profile) {
640 		add_options(ifp->ctx, ifp->name, ifp->options,
641 		    ifp->ctx->argc, ifp->ctx->argv);
642 		configure_interface1(ifp);
643 	}
644 	return 1;
645 }
646 
647 static void
configure_interface(struct interface * ifp,int argc,char ** argv,unsigned long long options)648 configure_interface(struct interface *ifp, int argc, char **argv,
649     unsigned long long options)
650 {
651 	time_t old;
652 
653 	old = ifp->options ? ifp->options->mtime : 0;
654 	dhcpcd_selectprofile(ifp, NULL);
655 	if (ifp->options == NULL) {
656 		/* dhcpcd cannot continue with this interface. */
657 		ifp->active = IF_INACTIVE;
658 		return;
659 	}
660 	add_options(ifp->ctx, ifp->name, ifp->options, argc, argv);
661 	ifp->options->options |= options;
662 	configure_interface1(ifp);
663 
664 	/* If the mtime has changed drop any old lease */
665 	if (old != 0 && ifp->options->mtime != old) {
666 		logwarnx("%s: config file changed, expiring leases",
667 		    ifp->name);
668 		dhcpcd_drop(ifp, 0);
669 	}
670 }
671 
672 static void
dhcpcd_initstate1(struct interface * ifp,int argc,char ** argv,unsigned long long options)673 dhcpcd_initstate1(struct interface *ifp, int argc, char **argv,
674     unsigned long long options)
675 {
676 	struct if_options *ifo;
677 
678 	configure_interface(ifp, argc, argv, options);
679 	if (!ifp->active)
680 		return;
681 
682 	ifo = ifp->options;
683 	ifo->options |= options;
684 
685 #ifdef INET6
686 	if (ifo->options & DHCPCD_IPV6 && ipv6_init(ifp->ctx) == -1) {
687 		logerr(__func__);
688 		ifo->options &= ~DHCPCD_IPV6;
689 	}
690 #endif
691 }
692 
693 static void
dhcpcd_initstate(struct interface * ifp,unsigned long long options)694 dhcpcd_initstate(struct interface *ifp, unsigned long long options)
695 {
696 
697 	dhcpcd_initstate1(ifp, ifp->ctx->argc, ifp->ctx->argv, options);
698 }
699 
700 static void
dhcpcd_reportssid(struct interface * ifp)701 dhcpcd_reportssid(struct interface *ifp)
702 {
703 	char pssid[IF_SSIDLEN * 4];
704 
705 	if (print_string(pssid, sizeof(pssid), OT_ESCSTRING,
706 	    ifp->ssid, ifp->ssid_len) == -1)
707 	{
708 		logerr(__func__);
709 		return;
710 	}
711 
712 	loginfox("%s: connected to Access Point: %s", ifp->name, pssid);
713 }
714 
715 static void
dhcpcd_nocarrier_roaming(struct interface * ifp)716 dhcpcd_nocarrier_roaming(struct interface *ifp)
717 {
718 
719 	loginfox("%s: carrier lost - roaming", ifp->name);
720 
721 #ifdef ARP
722 	arp_drop(ifp);
723 #endif
724 #ifdef INET
725 	dhcp_abort(ifp);
726 #endif
727 #ifdef DHCP6
728 	dhcp6_abort(ifp);
729 #endif
730 
731 	rt_build(ifp->ctx, AF_UNSPEC);
732 	script_runreason(ifp, "NOCARRIER_ROAMING");
733 }
734 
735 void
dhcpcd_handlecarrier(struct interface * ifp,int carrier,unsigned int flags)736 dhcpcd_handlecarrier(struct interface *ifp, int carrier, unsigned int flags)
737 {
738 	bool was_link_up = if_is_link_up(ifp);
739 	bool was_roaming = if_roaming(ifp);
740 
741 	ifp->carrier = carrier;
742 	ifp->flags = flags;
743 
744 	if (!if_is_link_up(ifp)) {
745 		if (!ifp->active || (!was_link_up && !was_roaming))
746 			return;
747 
748 		/*
749 		 * If the interface is roaming (generally on wireless)
750 		 * then while we are not up, we are not down either.
751 		 * Preserve the network state until we either disconnect
752 		 * or re-connect.
753 		 */
754 		if (!ifp->options->randomise_hwaddr && if_roaming(ifp)) {
755 			dhcpcd_nocarrier_roaming(ifp);
756 			return;
757 		}
758 
759 		loginfox("%s: carrier lost", ifp->name);
760 		script_runreason(ifp, "NOCARRIER");
761 		dhcpcd_drop(ifp, 0);
762 
763 		if (ifp->options->randomise_hwaddr) {
764 			bool is_up = ifp->flags & IFF_UP;
765 
766 			if (is_up)
767 				if_down(ifp);
768 			if (if_randomisemac(ifp) == -1 && errno != ENXIO)
769 				logerr(__func__);
770 			if (is_up)
771 				if_up(ifp);
772 		}
773 
774 		return;
775 	}
776 
777 	/*
778 	 * At this point carrier is NOT DOWN and we have IFF_UP.
779 	 * We should treat LINK_UNKNOWN as up as the driver may not support
780 	 * link state changes.
781 	 * The consideration of any other information about carrier should
782 	 * be handled in the OS specific if_carrier() function.
783 	 */
784 	if (was_link_up)
785 		return;
786 
787 	if (ifp->active) {
788 		if (carrier == LINK_UNKNOWN)
789 			loginfox("%s: carrier unknown, assuming up", ifp->name);
790 		else
791 			loginfox("%s: carrier acquired", ifp->name);
792 	}
793 
794 #if !defined(__linux__) && !defined(__NetBSD__)
795 	/* BSD does not emit RTM_NEWADDR or RTM_CHGADDR when the
796 	 * hardware address changes so we have to go
797 	 * through the disovery process to work it out. */
798 	dhcpcd_handleinterface(ifp->ctx, 0, ifp->name);
799 #endif
800 
801 	if (ifp->wireless) {
802 		uint8_t ossid[IF_SSIDLEN];
803 		size_t olen;
804 
805 		olen = ifp->ssid_len;
806 		memcpy(ossid, ifp->ssid, ifp->ssid_len);
807 		if_getssid(ifp);
808 
809 		/* If we changed SSID network, drop leases */
810 		if ((ifp->ssid_len != olen ||
811 		    memcmp(ifp->ssid, ossid, ifp->ssid_len)) && ifp->active)
812 		{
813 			dhcpcd_reportssid(ifp);
814 			dhcpcd_drop(ifp, 0);
815 #ifdef IPV4LL
816 			ipv4ll_reset(ifp);
817 #endif
818 		}
819 	}
820 
821 	if (!ifp->active)
822 		return;
823 
824 	dhcpcd_initstate(ifp, 0);
825 	script_runreason(ifp, "CARRIER");
826 
827 #ifdef INET6
828 	/* Set any IPv6 Routers we remembered to expire faster than they
829 	 * would normally as we maybe on a new network. */
830 	ipv6nd_startexpire(ifp);
831 #ifdef IPV6_MANAGETEMPADDR
832 	/* RFC4941 Section 3.5 */
833 	ipv6_regentempaddrs(ifp);
834 #endif
835 #endif
836 
837 	dhcpcd_startinterface(ifp);
838 }
839 
840 static void
warn_iaid_conflict(struct interface * ifp,uint16_t ia_type,uint8_t * iaid)841 warn_iaid_conflict(struct interface *ifp, uint16_t ia_type, uint8_t *iaid)
842 {
843 	struct interface *ifn;
844 #ifdef INET6
845 	size_t i;
846 	struct if_ia *ia;
847 #endif
848 
849 	TAILQ_FOREACH(ifn, ifp->ctx->ifaces, next) {
850 		if (ifn == ifp || !ifn->active)
851 			continue;
852 		if (ifn->options->options & DHCPCD_ANONYMOUS)
853 			continue;
854 		if (ia_type == 0 &&
855 		    memcmp(ifn->options->iaid, iaid,
856 		    sizeof(ifn->options->iaid)) == 0)
857 			break;
858 #ifdef INET6
859 		for (i = 0; i < ifn->options->ia_len; i++) {
860 			ia = &ifn->options->ia[i];
861 			if (ia->ia_type == ia_type &&
862 			    memcmp(ia->iaid, iaid, sizeof(ia->iaid)) == 0)
863 				break;
864 		}
865 #endif
866 	}
867 
868 	/* This is only a problem if the interfaces are on the same network. */
869 	if (ifn)
870 		logerrx("%s: IAID conflicts with one assigned to %s",
871 		    ifp->name, ifn->name);
872 }
873 
874 static void
dhcpcd_initduid(struct dhcpcd_ctx * ctx,struct interface * ifp)875 dhcpcd_initduid(struct dhcpcd_ctx *ctx, struct interface *ifp)
876 {
877 	char buf[DUID_LEN * 3];
878 
879 	if (ctx->duid != NULL) {
880 		if (ifp == NULL)
881 			goto log;
882 		return;
883 	}
884 
885 	duid_init(ctx, ifp);
886 	if (ctx->duid == NULL)
887 		return;
888 
889 log:
890 	loginfox("DUID %s",
891 	    hwaddr_ntoa(ctx->duid, ctx->duid_len, buf, sizeof(buf)));
892 }
893 
894 void
dhcpcd_startinterface(void * arg)895 dhcpcd_startinterface(void *arg)
896 {
897 	struct interface *ifp = arg;
898 	struct if_options *ifo = ifp->options;
899 
900 	if (ifo->options & DHCPCD_LINK && !if_is_link_up(ifp)) {
901 		loginfox("%s: waiting for carrier", ifp->name);
902 		return;
903 	}
904 
905 	if (ifo->options & (DHCPCD_DUID | DHCPCD_IPV6) &&
906 	    !(ifo->options & DHCPCD_ANONYMOUS))
907 	{
908 		char buf[sizeof(ifo->iaid) * 3];
909 #ifdef INET6
910 		size_t i;
911 		struct if_ia *ia;
912 #endif
913 
914 		/* Try and init DUID from the interface hardware address */
915 		dhcpcd_initduid(ifp->ctx, ifp);
916 
917 		/* Report IAIDs */
918 		loginfox("%s: IAID %s", ifp->name,
919 		    hwaddr_ntoa(ifo->iaid, sizeof(ifo->iaid),
920 		    buf, sizeof(buf)));
921 		warn_iaid_conflict(ifp, 0, ifo->iaid);
922 
923 #ifdef INET6
924 		for (i = 0; i < ifo->ia_len; i++) {
925 			ia = &ifo->ia[i];
926 			if (memcmp(ifo->iaid, ia->iaid, sizeof(ifo->iaid))) {
927 				loginfox("%s: IA type %u IAID %s",
928 				    ifp->name, ia->ia_type,
929 				    hwaddr_ntoa(ia->iaid, sizeof(ia->iaid),
930 				    buf, sizeof(buf)));
931 				warn_iaid_conflict(ifp, ia->ia_type, ia->iaid);
932 			}
933 		}
934 #endif
935 	}
936 
937 #ifdef INET6
938 	if (ifo->options & DHCPCD_IPV6 && ipv6_start(ifp) == -1) {
939 		logerr("%s: ipv6_start", ifp->name);
940 		ifo->options &= ~DHCPCD_IPV6;
941 	}
942 
943 	if (ifo->options & DHCPCD_IPV6) {
944 		if (ifp->active == IF_ACTIVE_USER) {
945 			ipv6_startstatic(ifp);
946 
947 			if (ifo->options & DHCPCD_IPV6RS)
948 				ipv6nd_startrs(ifp);
949 		}
950 
951 #ifdef DHCP6
952 		/* DHCPv6 could be turned off, but the interface
953 		 * is still delegated to. */
954 		if (ifp->active)
955 			dhcp6_find_delegates(ifp);
956 
957 		if (ifo->options & DHCPCD_DHCP6) {
958 			if (ifp->active == IF_ACTIVE_USER) {
959 				enum DH6S d6_state;
960 
961 				if (ifo->options & DHCPCD_IA_FORCED)
962 					d6_state = DH6S_INIT;
963 				else if (ifo->options & DHCPCD_INFORM6)
964 					d6_state = DH6S_INFORM;
965 				else
966 					d6_state = DH6S_CONFIRM;
967 				if (dhcp6_start(ifp, d6_state) == -1)
968 					logerr("%s: dhcp6_start", ifp->name);
969 			}
970 		}
971 #endif
972 	}
973 #endif
974 
975 #ifdef INET
976 	if (ifo->options & DHCPCD_IPV4 && ifp->active == IF_ACTIVE_USER) {
977 		/* Ensure we have an IPv4 state before starting DHCP */
978 		if (ipv4_getstate(ifp) != NULL)
979 			dhcp_start(ifp);
980 	}
981 #endif
982 }
983 
984 static void
dhcpcd_prestartinterface(void * arg)985 dhcpcd_prestartinterface(void *arg)
986 {
987 	struct interface *ifp = arg;
988 	struct dhcpcd_ctx *ctx = ifp->ctx;
989 	bool randmac_down;
990 
991 	if (ifp->carrier <= LINK_DOWN &&
992 	    ifp->options->randomise_hwaddr &&
993 	    ifp->flags & IFF_UP)
994 	{
995 		if_down(ifp);
996 		randmac_down = true;
997 	} else
998 		randmac_down = false;
999 
1000 	if ((!(ctx->options & DHCPCD_MANAGER) ||
1001 	    ifp->options->options & DHCPCD_IF_UP || randmac_down) &&
1002 	    !(ifp->flags & IFF_UP))
1003 	{
1004 		if (ifp->options->randomise_hwaddr &&
1005 		    if_randomisemac(ifp) == -1)
1006 			logerr(__func__);
1007 		if (if_up(ifp) == -1)
1008 			logerr(__func__);
1009 	}
1010 
1011 	dhcpcd_startinterface(ifp);
1012 }
1013 
1014 static void
run_preinit(struct interface * ifp)1015 run_preinit(struct interface *ifp)
1016 {
1017 
1018 	if (ifp->ctx->options & DHCPCD_TEST)
1019 		return;
1020 
1021 	script_runreason(ifp, "PREINIT");
1022 	if (ifp->wireless && if_is_link_up(ifp))
1023 		dhcpcd_reportssid(ifp);
1024 	if (ifp->options->options & DHCPCD_LINK && ifp->carrier != LINK_UNKNOWN)
1025 		script_runreason(ifp,
1026 		    ifp->carrier == LINK_UP ? "CARRIER" : "NOCARRIER");
1027 }
1028 
1029 void
dhcpcd_activateinterface(struct interface * ifp,unsigned long long options)1030 dhcpcd_activateinterface(struct interface *ifp, unsigned long long options)
1031 {
1032 
1033 	if (ifp->active)
1034 		return;
1035 
1036 	/* IF_ACTIVE_USER will start protocols when the interface is started.
1037 	 * IF_ACTIVE will ask the protocols for setup,
1038 	 * such as any delegated prefixes. */
1039 	ifp->active = IF_ACTIVE;
1040 	dhcpcd_initstate(ifp, options);
1041 
1042 	/* It's possible we might not have been able to load
1043 	 * a config. */
1044 	if (!ifp->active)
1045 		return;
1046 
1047 	run_preinit(ifp);
1048 	dhcpcd_prestartinterface(ifp);
1049 }
1050 
1051 int
dhcpcd_handleinterface(void * arg,int action,const char * ifname)1052 dhcpcd_handleinterface(void *arg, int action, const char *ifname)
1053 {
1054 	struct dhcpcd_ctx *ctx = arg;
1055 	struct ifaddrs *ifaddrs;
1056 	struct if_head *ifs;
1057 	struct interface *ifp, *iff;
1058 	const char * const argv[] = { ifname };
1059 	int e;
1060 
1061 	if (action == -1) {
1062 		ifp = if_find(ctx->ifaces, ifname);
1063 		if (ifp == NULL) {
1064 			errno = ESRCH;
1065 			return -1;
1066 		}
1067 		if (ifp->active) {
1068 			logdebugx("%s: interface departed", ifp->name);
1069 			stop_interface(ifp, "DEPARTED");
1070 		}
1071 		TAILQ_REMOVE(ctx->ifaces, ifp, next);
1072 		if_free(ifp);
1073 		return 0;
1074 	}
1075 
1076 	ifs = if_discover(ctx, &ifaddrs, -1, UNCONST(argv));
1077 	if (ifs == NULL) {
1078 		logerr(__func__);
1079 		return -1;
1080 	}
1081 
1082 	ifp = if_find(ifs, ifname);
1083 	if (ifp == NULL) {
1084 		/* This can happen if an interface is quickly added
1085 		 * and then removed. */
1086 		errno = ENOENT;
1087 		e = -1;
1088 		goto out;
1089 	}
1090 	e = 1;
1091 
1092 	/* Check if we already have the interface */
1093 	iff = if_find(ctx->ifaces, ifp->name);
1094 
1095 	if (iff != NULL) {
1096 		if (iff->active)
1097 			logdebugx("%s: interface updated", iff->name);
1098 		/* The flags and hwaddr could have changed */
1099 		iff->flags = ifp->flags;
1100 		iff->hwlen = ifp->hwlen;
1101 		if (ifp->hwlen != 0)
1102 			memcpy(iff->hwaddr, ifp->hwaddr, iff->hwlen);
1103 	} else {
1104 		TAILQ_REMOVE(ifs, ifp, next);
1105 		TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next);
1106 		if (ifp->active) {
1107 			logdebugx("%s: interface added", ifp->name);
1108 			dhcpcd_initstate(ifp, 0);
1109 			run_preinit(ifp);
1110 		}
1111 		iff = ifp;
1112 	}
1113 
1114 	if (action > 0) {
1115 		if_learnaddrs(ctx, ifs, &ifaddrs);
1116 		if (iff->active)
1117 			dhcpcd_prestartinterface(iff);
1118 	}
1119 
1120 out:
1121 	/* Free our discovered list */
1122 	while ((ifp = TAILQ_FIRST(ifs))) {
1123 		TAILQ_REMOVE(ifs, ifp, next);
1124 		if_free(ifp);
1125 	}
1126 	free(ifs);
1127 	if_freeifaddrs(ctx, &ifaddrs);
1128 
1129 	return e;
1130 }
1131 
1132 static void
dhcpcd_handlelink(void * arg,unsigned short events)1133 dhcpcd_handlelink(void *arg, unsigned short events)
1134 {
1135 	struct dhcpcd_ctx *ctx = arg;
1136 
1137 	if (events != ELE_READ)
1138 		logerrx("%s: unexpected event 0x%04x", __func__, events);
1139 
1140 	if (if_handlelink(ctx) == -1) {
1141 		if (errno == ENOBUFS || errno == ENOMEM) {
1142 			dhcpcd_linkoverflow(ctx);
1143 			return;
1144 		}
1145 		if (errno != ENOTSUP)
1146 			logerr(__func__);
1147 	}
1148 }
1149 
1150 static void
dhcpcd_checkcarrier(void * arg)1151 dhcpcd_checkcarrier(void *arg)
1152 {
1153 	struct interface *ifp0 = arg, *ifp;
1154 
1155 	ifp = if_find(ifp0->ctx->ifaces, ifp0->name);
1156 	if (ifp == NULL || ifp->carrier == ifp0->carrier)
1157 		return;
1158 
1159 	dhcpcd_handlecarrier(ifp, ifp0->carrier, ifp0->flags);
1160 	if_free(ifp0);
1161 }
1162 
1163 #ifndef SMALL
1164 static void
dhcpcd_setlinkrcvbuf(struct dhcpcd_ctx * ctx)1165 dhcpcd_setlinkrcvbuf(struct dhcpcd_ctx *ctx)
1166 {
1167 	socklen_t socklen;
1168 
1169 	if (ctx->link_rcvbuf == 0)
1170 		return;
1171 
1172 	logdebugx("setting route socket receive buffer size to %d bytes",
1173 	    ctx->link_rcvbuf);
1174 
1175 	socklen = sizeof(ctx->link_rcvbuf);
1176 	if (setsockopt(ctx->link_fd, SOL_SOCKET,
1177 	    SO_RCVBUF, &ctx->link_rcvbuf, socklen) == -1)
1178 		logerr(__func__);
1179 }
1180 #endif
1181 
1182 static void
dhcpcd_runprestartinterface(void * arg)1183 dhcpcd_runprestartinterface(void *arg)
1184 {
1185 	struct interface *ifp = arg;
1186 
1187 	run_preinit(ifp);
1188 	dhcpcd_prestartinterface(ifp);
1189 }
1190 
1191 void
dhcpcd_linkoverflow(struct dhcpcd_ctx * ctx)1192 dhcpcd_linkoverflow(struct dhcpcd_ctx *ctx)
1193 {
1194 	socklen_t socklen;
1195 	int rcvbuflen;
1196 	char buf[2048];
1197 	ssize_t rlen;
1198 	size_t rcnt;
1199 	struct if_head *ifaces;
1200 	struct ifaddrs *ifaddrs;
1201 	struct interface *ifp, *ifn, *ifp1;
1202 
1203 	socklen = sizeof(rcvbuflen);
1204 	if (getsockopt(ctx->link_fd, SOL_SOCKET,
1205 	    SO_RCVBUF, &rcvbuflen, &socklen) == -1) {
1206 		logerr("%s: getsockopt", __func__);
1207 		rcvbuflen = 0;
1208 	}
1209 #ifdef __linux__
1210 	else
1211 		rcvbuflen /= 2;
1212 #endif
1213 
1214 	logerrx("route socket overflowed (rcvbuflen %d)"
1215 	    " - learning interface state", rcvbuflen);
1216 
1217 	/* Drain the socket.
1218 	 * We cannot open a new one due to privsep. */
1219 	rcnt = 0;
1220 	do {
1221 		rlen = read(ctx->link_fd, buf, sizeof(buf));
1222 		if (++rcnt % 1000 == 0)
1223 			logwarnx("drained %zu messages", rcnt);
1224 	} while (rlen != -1 || errno == ENOBUFS || errno == ENOMEM);
1225 	if (rcnt % 1000 != 0)
1226 		logwarnx("drained %zu messages", rcnt);
1227 
1228 	/* Work out the current interfaces. */
1229 	ifaces = if_discover(ctx, &ifaddrs, ctx->ifc, ctx->ifv);
1230 	if (ifaces == NULL) {
1231 		logerr(__func__);
1232 		return;
1233 	}
1234 
1235 	/* Punt departed interfaces */
1236 	TAILQ_FOREACH_SAFE(ifp, ctx->ifaces, next, ifn) {
1237 		if (if_find(ifaces, ifp->name) != NULL)
1238 			continue;
1239 		dhcpcd_handleinterface(ctx, -1, ifp->name);
1240 	}
1241 
1242 	/* Add new interfaces */
1243 	while ((ifp = TAILQ_FIRST(ifaces)) != NULL ) {
1244 		TAILQ_REMOVE(ifaces, ifp, next);
1245 		ifp1 = if_find(ctx->ifaces, ifp->name);
1246 		if (ifp1 != NULL) {
1247 			/* If the interface already exists,
1248 			 * check carrier state.
1249 			 * dhcpcd_checkcarrier will free ifp. */
1250 			eloop_timeout_add_sec(ctx->eloop, 0,
1251 			    dhcpcd_checkcarrier, ifp);
1252 			continue;
1253 		}
1254 		TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next);
1255 		if (ifp->active) {
1256 			dhcpcd_initstate(ifp, 0);
1257 			eloop_timeout_add_sec(ctx->eloop, 0,
1258 			    dhcpcd_runprestartinterface, ifp);
1259 		}
1260 	}
1261 	free(ifaces);
1262 
1263 	/* Update address state. */
1264 	if_markaddrsstale(ctx->ifaces);
1265 	if_learnaddrs(ctx, ctx->ifaces, &ifaddrs);
1266 	if_deletestaleaddrs(ctx->ifaces);
1267 	if_freeifaddrs(ctx, &ifaddrs);
1268 }
1269 
1270 void
dhcpcd_handlehwaddr(struct interface * ifp,uint16_t hwtype,const void * hwaddr,uint8_t hwlen)1271 dhcpcd_handlehwaddr(struct interface *ifp,
1272     uint16_t hwtype, const void *hwaddr, uint8_t hwlen)
1273 {
1274 	char buf[sizeof(ifp->hwaddr) * 3];
1275 
1276 	if (hwaddr == NULL || !if_valid_hwaddr(hwaddr, hwlen))
1277 		hwlen = 0;
1278 
1279 	if (hwlen > sizeof(ifp->hwaddr)) {
1280 		errno = ENOBUFS;
1281 		logerr("%s: %s", __func__, ifp->name);
1282 		return;
1283 	}
1284 
1285 	if (ifp->hwtype != hwtype) {
1286 		if (ifp->active)
1287 			loginfox("%s: hardware address type changed"
1288 			    " from %d to %d", ifp->name, ifp->hwtype, hwtype);
1289 		ifp->hwtype = hwtype;
1290 	}
1291 
1292 	if (ifp->hwlen == hwlen &&
1293 	    (hwlen == 0 || memcmp(ifp->hwaddr, hwaddr, hwlen) == 0))
1294 		return;
1295 
1296 	if (ifp->active) {
1297 		loginfox("%s: old hardware address: %s", ifp->name,
1298 		    hwaddr_ntoa(ifp->hwaddr, ifp->hwlen, buf, sizeof(buf)));
1299 		loginfox("%s: new hardware address: %s", ifp->name,
1300 		    hwaddr_ntoa(hwaddr, hwlen, buf, sizeof(buf)));
1301 	}
1302 	ifp->hwlen = hwlen;
1303 	if (hwaddr != NULL)
1304 		memcpy(ifp->hwaddr, hwaddr, hwlen);
1305 }
1306 
1307 static void
if_reboot(struct interface * ifp,int argc,char ** argv)1308 if_reboot(struct interface *ifp, int argc, char **argv)
1309 {
1310 #ifdef INET
1311 	unsigned long long oldopts;
1312 
1313 	oldopts = ifp->options->options;
1314 #endif
1315 	script_runreason(ifp, "RECONFIGURE");
1316 	dhcpcd_initstate1(ifp, argc, argv, 0);
1317 #ifdef INET
1318 	dhcp_reboot_newopts(ifp, oldopts);
1319 #endif
1320 #ifdef DHCP6
1321 	dhcp6_reboot(ifp);
1322 #endif
1323 	dhcpcd_prestartinterface(ifp);
1324 }
1325 
1326 static void
reload_config(struct dhcpcd_ctx * ctx)1327 reload_config(struct dhcpcd_ctx *ctx)
1328 {
1329 	struct if_options *ifo;
1330 
1331 	free_globals(ctx);
1332 	if ((ifo = read_config(ctx, NULL, NULL, NULL)) == NULL)
1333 		return;
1334 	add_options(ctx, NULL, ifo, ctx->argc, ctx->argv);
1335 	/* We need to preserve these options. */
1336 	if (ctx->options & DHCPCD_STARTED)
1337 		ifo->options |= DHCPCD_STARTED;
1338 	if (ctx->options & DHCPCD_MANAGER)
1339 		ifo->options |= DHCPCD_MANAGER;
1340 	if (ctx->options & DHCPCD_DAEMONISED)
1341 		ifo->options |= DHCPCD_DAEMONISED;
1342 	if (ctx->options & DHCPCD_PRIVSEP)
1343 		ifo->options |= DHCPCD_PRIVSEP;
1344 	ctx->options = ifo->options;
1345 	free_options(ctx, ifo);
1346 }
1347 
1348 static void
reconf_reboot(struct dhcpcd_ctx * ctx,int action,int argc,char ** argv,int oi)1349 reconf_reboot(struct dhcpcd_ctx *ctx, int action, int argc, char **argv, int oi)
1350 {
1351 	int i;
1352 	struct interface *ifp;
1353 
1354 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1355 		for (i = oi; i < argc; i++) {
1356 			if (strcmp(ifp->name, argv[i]) == 0)
1357 				break;
1358 		}
1359 		if (oi != argc && i == argc)
1360 			continue;
1361 		if (ifp->active == IF_ACTIVE_USER) {
1362 			if (action)
1363 				if_reboot(ifp, argc, argv);
1364 #ifdef INET
1365 			else
1366 				ipv4_applyaddr(ifp);
1367 #endif
1368 		} else if (i != argc) {
1369 			ifp->active = IF_ACTIVE_USER;
1370 			dhcpcd_initstate1(ifp, argc, argv, 0);
1371 			run_preinit(ifp);
1372 			dhcpcd_prestartinterface(ifp);
1373 		}
1374 	}
1375 }
1376 
1377 static void
stop_all_interfaces(struct dhcpcd_ctx * ctx,unsigned long long opts)1378 stop_all_interfaces(struct dhcpcd_ctx *ctx, unsigned long long opts)
1379 {
1380 	struct interface *ifp;
1381 
1382 	ctx->options |= DHCPCD_EXITING;
1383 	if (ctx->ifaces == NULL)
1384 		return;
1385 
1386 	/* Drop the last interface first */
1387 	TAILQ_FOREACH_REVERSE(ifp, ctx->ifaces, if_head, next) {
1388 		if (!ifp->active)
1389 			continue;
1390 		ifp->options->options |= opts;
1391 		if (ifp->options->options & DHCPCD_RELEASE)
1392 			ifp->options->options &= ~DHCPCD_PERSISTENT;
1393 		ifp->options->options |= DHCPCD_EXITING;
1394 		stop_interface(ifp, NULL);
1395 	}
1396 }
1397 
1398 static void
dhcpcd_ifrenew(struct interface * ifp)1399 dhcpcd_ifrenew(struct interface *ifp)
1400 {
1401 
1402 	if (!ifp->active)
1403 		return;
1404 
1405 	if (ifp->options->options & DHCPCD_LINK && !if_is_link_up(ifp))
1406 		return;
1407 
1408 #ifdef INET
1409 	dhcp_renew(ifp);
1410 #endif
1411 #ifdef INET6
1412 #define DHCPCD_RARENEW (DHCPCD_IPV6 | DHCPCD_IPV6RS)
1413 	if ((ifp->options->options & DHCPCD_RARENEW) == DHCPCD_RARENEW)
1414 		ipv6nd_startrs(ifp);
1415 #endif
1416 #ifdef DHCP6
1417 	dhcp6_renew(ifp);
1418 #endif
1419 }
1420 
1421 static void
dhcpcd_renew(struct dhcpcd_ctx * ctx)1422 dhcpcd_renew(struct dhcpcd_ctx *ctx)
1423 {
1424 	struct interface *ifp;
1425 
1426 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1427 		dhcpcd_ifrenew(ifp);
1428 	}
1429 }
1430 
1431 #ifdef USE_SIGNALS
1432 #define sigmsg "received %s, %s"
1433 static volatile bool dhcpcd_exiting = false;
1434 void
dhcpcd_signal_cb(int sig,void * arg)1435 dhcpcd_signal_cb(int sig, void *arg)
1436 {
1437 	struct dhcpcd_ctx *ctx = arg;
1438 	unsigned long long opts;
1439 	int exit_code;
1440 
1441 	if (ctx->options & DHCPCD_DUMPLEASE) {
1442 		eloop_exit(ctx->eloop, EXIT_FAILURE);
1443 		return;
1444 	}
1445 
1446 	if (sig != SIGCHLD && ctx->options & DHCPCD_FORKED) {
1447 		if (sig != SIGHUP &&
1448 		    write(ctx->fork_fd, &sig, sizeof(sig)) == -1)
1449 			logerr("%s: write", __func__);
1450 		return;
1451 	}
1452 
1453 	opts = 0;
1454 	exit_code = EXIT_FAILURE;
1455 	switch (sig) {
1456 	case SIGINT:
1457 		loginfox(sigmsg, "SIGINT", "stopping");
1458 		break;
1459 	case SIGTERM:
1460 		loginfox(sigmsg, "SIGTERM", "stopping");
1461 		exit_code = EXIT_SUCCESS;
1462 		break;
1463 	case SIGALRM:
1464 		loginfox(sigmsg, "SIGALRM", "releasing");
1465 		opts |= DHCPCD_RELEASE;
1466 		exit_code = EXIT_SUCCESS;
1467 		break;
1468 	case SIGHUP:
1469 		loginfox(sigmsg, "SIGHUP", "rebinding");
1470 		reload_config(ctx);
1471 		/* Preserve any options passed on the commandline
1472 		 * when we were started. */
1473 		reconf_reboot(ctx, 1, ctx->argc, ctx->argv,
1474 		    ctx->argc - ctx->ifc);
1475 		return;
1476 	case SIGUSR1:
1477 		loginfox(sigmsg, "SIGUSR1", "renewing");
1478 		dhcpcd_renew(ctx);
1479 		return;
1480 	case SIGUSR2:
1481 		loginfox(sigmsg, "SIGUSR2", "reopening log");
1482 #ifdef PRIVSEP
1483 		if (IN_PRIVSEP(ctx)) {
1484 			if (ps_root_logreopen(ctx) == -1)
1485 				logerr("ps_root_logreopen");
1486 			return;
1487 		}
1488 #endif
1489 		if (logopen(ctx->logfile) == -1)
1490 			logerr("logopen");
1491 		return;
1492 	case SIGCHLD:
1493 #ifdef PRIVSEP
1494 		ps_root_signalcb(sig, ctx);
1495 #else
1496 		while (waitpid(-1, NULL, WNOHANG) > 0)
1497 			;
1498 #endif
1499 		return;
1500 	default:
1501 		logerrx("received signal %d but don't know what to do with it",
1502 		    sig);
1503 		return;
1504 	}
1505 
1506 	/*
1507 	 * Privsep has a mini-eloop for reading data from other processes.
1508 	 * This mini-eloop processes signals as well so we can reap children.
1509 	 * During teardown we don't want to process SIGTERM or SIGINT again,
1510 	 * as that could trigger memory issues.
1511 	 */
1512 	if (dhcpcd_exiting)
1513 		return;
1514 
1515 	dhcpcd_exiting = true;
1516 	if (!(ctx->options & DHCPCD_TEST))
1517 		stop_all_interfaces(ctx, opts);
1518 	eloop_exit(ctx->eloop, exit_code);
1519 	dhcpcd_exiting = false;
1520 }
1521 #endif
1522 
1523 int
dhcpcd_handleargs(struct dhcpcd_ctx * ctx,struct fd_list * fd,int argc,char ** argv)1524 dhcpcd_handleargs(struct dhcpcd_ctx *ctx, struct fd_list *fd,
1525     int argc, char **argv)
1526 {
1527 	struct interface *ifp;
1528 	struct if_options *ifo;
1529 	unsigned long long opts, orig_opts;
1530 	int opt, oi, oifind, do_reboot, do_renew, af = AF_UNSPEC;
1531 	size_t len, l, nifaces;
1532 	char *tmp, *p;
1533 
1534 	/* Special commands for our control socket
1535 	 * as the other end should be blocking until it gets the
1536 	 * expected reply we should be safely able just to change the
1537 	 * write callback on the fd */
1538 	/* Make any change here in privsep-control.c as well. */
1539 	if (strcmp(*argv, "--version") == 0) {
1540 		return control_queue(fd, UNCONST(VERSION),
1541 		    strlen(VERSION) + 1);
1542 	} else if (strcmp(*argv, "--getconfigfile") == 0) {
1543 		return control_queue(fd, UNCONST(fd->ctx->cffile),
1544 		    strlen(fd->ctx->cffile) + 1);
1545 	} else if (strcmp(*argv, "--getinterfaces") == 0) {
1546 		oifind = argc = 0;
1547 		goto dumplease;
1548 	} else if (strcmp(*argv, "--listen") == 0) {
1549 		fd->flags |= FD_LISTEN;
1550 		return 0;
1551 	}
1552 
1553 	/* Log the command */
1554 	len = 1;
1555 	for (opt = 0; opt < argc; opt++)
1556 		len += strlen(argv[opt]) + 1;
1557 	tmp = malloc(len);
1558 	if (tmp == NULL)
1559 		return -1;
1560 	p = tmp;
1561 	for (opt = 0; opt < argc; opt++) {
1562 		l = strlen(argv[opt]);
1563 		strlcpy(p, argv[opt], len);
1564 		len -= l + 1;
1565 		p += l;
1566 		*p++ = ' ';
1567 	}
1568 	*--p = '\0';
1569 	loginfox("control command: %s", tmp);
1570 	free(tmp);
1571 
1572 	optind = 0;
1573 	oi = 0;
1574 	opts = 0;
1575 	do_reboot = do_renew = 0;
1576 	while ((opt = getopt_long(argc, argv, IF_OPTS, cf_options, &oi)) != -1)
1577 	{
1578 		switch (opt) {
1579 		case 'g':
1580 			/* Assumed if below not set */
1581 			break;
1582 		case 'k':
1583 			opts |= DHCPCD_RELEASE;
1584 			break;
1585 		case 'n':
1586 			do_reboot = 1;
1587 			break;
1588 		case 'p':
1589 			opts |= DHCPCD_PERSISTENT;
1590 			break;
1591 		case 'x':
1592 			opts |= DHCPCD_EXITING;
1593 			break;
1594 		case 'N':
1595 			do_renew = 1;
1596 			break;
1597 		case 'U':
1598 			opts |= DHCPCD_DUMPLEASE;
1599 			break;
1600 		case '4':
1601 			af = AF_INET;
1602 			break;
1603 		case '6':
1604 			af = AF_INET6;
1605 			break;
1606 		}
1607 	}
1608 
1609 	/* store the index; the optind will change when a getopt get called */
1610 	oifind = optind;
1611 
1612 	if (opts & DHCPCD_DUMPLEASE) {
1613 		ctx->options |= DHCPCD_DUMPLEASE;
1614 dumplease:
1615 		nifaces = 0;
1616 		TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1617 			if (!ifp->active)
1618 				continue;
1619 			for (oi = oifind; oi < argc; oi++) {
1620 				if (strcmp(ifp->name, argv[oi]) == 0)
1621 					break;
1622 			}
1623 			if (oifind == argc || oi < argc) {
1624 				opt = send_interface(NULL, ifp, af);
1625 				if (opt == -1)
1626 					goto dumperr;
1627 				nifaces += (size_t)opt;
1628 			}
1629 		}
1630 		if (write(fd->fd, &nifaces, sizeof(nifaces)) != sizeof(nifaces))
1631 			goto dumperr;
1632 		TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1633 			if (!ifp->active)
1634 				continue;
1635 			for (oi = oifind; oi < argc; oi++) {
1636 				if (strcmp(ifp->name, argv[oi]) == 0)
1637 					break;
1638 			}
1639 			if (oifind == argc || oi < argc) {
1640 				if (send_interface(fd, ifp, af) == -1)
1641 					goto dumperr;
1642 			}
1643 		}
1644 		ctx->options &= ~DHCPCD_DUMPLEASE;
1645 		return 0;
1646 dumperr:
1647 		ctx->options &= ~DHCPCD_DUMPLEASE;
1648 		return -1;
1649 	}
1650 
1651 	/* Only privileged users can control dhcpcd via the socket. */
1652 	if (fd->flags & FD_UNPRIV) {
1653 		errno = EPERM;
1654 		return -1;
1655 	}
1656 
1657 	if (opts & (DHCPCD_EXITING | DHCPCD_RELEASE)) {
1658 		if (oifind == argc && af == AF_UNSPEC) {
1659 			stop_all_interfaces(ctx, opts);
1660 			eloop_exit(ctx->eloop, EXIT_SUCCESS);
1661 			return 0;
1662 		}
1663 
1664 		TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1665 			if (!ifp->active)
1666 				continue;
1667 			for (oi = oifind; oi < argc; oi++) {
1668 				if (strcmp(ifp->name, argv[oi]) == 0)
1669 					break;
1670 			}
1671 			if (oi == argc)
1672 				continue;
1673 
1674 			ifo = ifp->options;
1675 			orig_opts = ifo->options;
1676 			ifo->options |= opts;
1677 			if (opts & DHCPCD_RELEASE)
1678 				ifo->options &= ~DHCPCD_PERSISTENT;
1679 			switch (af) {
1680 			case AF_INET:
1681 				ifo->options &= ~DHCPCD_IPV4;
1682 				break;
1683 			case AF_INET6:
1684 				ifo->options &= ~DHCPCD_IPV6;
1685 				break;
1686 			}
1687 			if (af != AF_UNSPEC)
1688 				dhcpcd_drop_af(ifp, 1, af);
1689 			else
1690 				stop_interface(ifp, NULL);
1691 			ifo->options = orig_opts;
1692 		}
1693 		return 0;
1694 	}
1695 
1696 	if (do_renew) {
1697 		if (oifind == argc) {
1698 			dhcpcd_renew(ctx);
1699 			return 0;
1700 		}
1701 		for (oi = oifind; oi < argc; oi++) {
1702 			if ((ifp = if_find(ctx->ifaces, argv[oi])) == NULL)
1703 				continue;
1704 			dhcpcd_ifrenew(ifp);
1705 		}
1706 		return 0;
1707 	}
1708 
1709 	reload_config(ctx);
1710 	/* XXX: Respect initial commandline options? */
1711 	reconf_reboot(ctx, do_reboot, argc, argv, oifind);
1712 	return 0;
1713 }
1714 
1715 static void dhcpcd_readdump1(void *, unsigned short);
1716 
1717 static void
dhcpcd_readdump2(void * arg,unsigned short events)1718 dhcpcd_readdump2(void *arg, unsigned short events)
1719 {
1720 	struct dhcpcd_ctx *ctx = arg;
1721 	ssize_t len;
1722 	int exit_code = EXIT_FAILURE;
1723 
1724 	if (events != ELE_READ)
1725 		logerrx("%s: unexpected event 0x%04x", __func__, events);
1726 
1727 	len = read(ctx->control_fd, ctx->ctl_buf + ctx->ctl_bufpos,
1728 	    ctx->ctl_buflen - ctx->ctl_bufpos);
1729 	if (len == -1) {
1730 		logerr(__func__);
1731 		goto finished;
1732 	} else if (len == 0)
1733 		goto finished;
1734 	if ((size_t)len + ctx->ctl_bufpos != ctx->ctl_buflen) {
1735 		ctx->ctl_bufpos += (size_t)len;
1736 		return;
1737 	}
1738 
1739 	if (ctx->ctl_buf[ctx->ctl_buflen - 1] != '\0') /* unlikely */
1740 		ctx->ctl_buf[ctx->ctl_buflen - 1] = '\0';
1741 	script_dump(ctx->ctl_buf, ctx->ctl_buflen);
1742 	fflush(stdout);
1743 	if (--ctx->ctl_extra != 0) {
1744 		putchar('\n');
1745 		if (eloop_event_add(ctx->eloop, ctx->control_fd, ELE_READ,
1746 		    dhcpcd_readdump1, ctx) == -1)
1747 			logerr("%s: eloop_event_add", __func__);
1748 		return;
1749 	}
1750 	exit_code = EXIT_SUCCESS;
1751 
1752 finished:
1753 	shutdown(ctx->control_fd, SHUT_RDWR);
1754 	eloop_exit(ctx->eloop, exit_code);
1755 }
1756 
1757 static void
dhcpcd_readdump1(void * arg,unsigned short events)1758 dhcpcd_readdump1(void *arg, unsigned short events)
1759 {
1760 	struct dhcpcd_ctx *ctx = arg;
1761 	ssize_t len;
1762 
1763 	if (events != ELE_READ)
1764 		logerrx("%s: unexpected event 0x%04x", __func__, events);
1765 
1766 	len = read(ctx->control_fd, &ctx->ctl_buflen, sizeof(ctx->ctl_buflen));
1767 	if (len != sizeof(ctx->ctl_buflen)) {
1768 		if (len != -1)
1769 			errno = EINVAL;
1770 		goto err;
1771 	}
1772 	if (ctx->ctl_buflen > SSIZE_MAX) {
1773 		errno = ENOBUFS;
1774 		goto err;
1775 	}
1776 
1777 	free(ctx->ctl_buf);
1778 	ctx->ctl_buf = malloc(ctx->ctl_buflen);
1779 	if (ctx->ctl_buf == NULL)
1780 		goto err;
1781 
1782 	ctx->ctl_bufpos = 0;
1783 	if (eloop_event_add(ctx->eloop, ctx->control_fd, ELE_READ,
1784 	    dhcpcd_readdump2, ctx) == -1)
1785 		logerr("%s: eloop_event_add", __func__);
1786 	return;
1787 
1788 err:
1789 	logerr(__func__);
1790 	eloop_exit(ctx->eloop, EXIT_FAILURE);
1791 }
1792 
1793 static void
dhcpcd_readdump0(void * arg,unsigned short events)1794 dhcpcd_readdump0(void *arg, unsigned short events)
1795 {
1796 	struct dhcpcd_ctx *ctx = arg;
1797 	ssize_t len;
1798 
1799 	if (events != ELE_READ)
1800 		logerrx("%s: unexpected event 0x%04x", __func__, events);
1801 
1802 	len = read(ctx->control_fd, &ctx->ctl_extra, sizeof(ctx->ctl_extra));
1803 	if (len != sizeof(ctx->ctl_extra)) {
1804 		if (len != -1)
1805 			errno = EINVAL;
1806 		logerr(__func__);
1807 		eloop_exit(ctx->eloop, EXIT_FAILURE);
1808 		return;
1809 	}
1810 
1811 	if (ctx->ctl_extra == 0) {
1812 		eloop_exit(ctx->eloop, EXIT_SUCCESS);
1813 		return;
1814 	}
1815 
1816 	if (eloop_event_add(ctx->eloop, ctx->control_fd, ELE_READ,
1817 	    dhcpcd_readdump1, ctx) == -1)
1818 		logerr("%s: eloop_event_add", __func__);
1819 }
1820 
1821 static void
dhcpcd_readdumptimeout(void * arg)1822 dhcpcd_readdumptimeout(void *arg)
1823 {
1824 	struct dhcpcd_ctx *ctx = arg;
1825 
1826 	logerrx(__func__);
1827 	eloop_exit(ctx->eloop, EXIT_FAILURE);
1828 }
1829 
1830 static int
dhcpcd_readdump(struct dhcpcd_ctx * ctx)1831 dhcpcd_readdump(struct dhcpcd_ctx *ctx)
1832 {
1833 
1834 	ctx->options |=	DHCPCD_FORKED;
1835 	if (eloop_timeout_add_sec(ctx->eloop, 5,
1836 	    dhcpcd_readdumptimeout, ctx) == -1)
1837 		return -1;
1838 	return eloop_event_add(ctx->eloop, ctx->control_fd, ELE_READ,
1839 	    dhcpcd_readdump0, ctx);
1840 }
1841 
1842 static void
dhcpcd_fork_cb(void * arg,unsigned short events)1843 dhcpcd_fork_cb(void *arg, unsigned short events)
1844 {
1845 	struct dhcpcd_ctx *ctx = arg;
1846 	int exit_code;
1847 	ssize_t len;
1848 
1849 	if (!(events & ELE_READ))
1850 		logerrx("%s: unexpected event 0x%04x", __func__, events);
1851 
1852 	len = read(ctx->fork_fd, &exit_code, sizeof(exit_code));
1853 	if (len == -1) {
1854 		logerr(__func__);
1855 		eloop_exit(ctx->eloop, EXIT_FAILURE);
1856 		return;
1857 	}
1858 	if (len == 0) {
1859 		if (ctx->options & DHCPCD_FORKED) {
1860 			logerrx("%s: dhcpcd manager hungup", __func__);
1861 			eloop_exit(ctx->eloop, EXIT_FAILURE);
1862 		} else {
1863 			// Launcher exited
1864 			eloop_event_delete(ctx->eloop, ctx->fork_fd);
1865 			close(ctx->fork_fd);
1866 			ctx->fork_fd = -1;
1867 		}
1868 		return;
1869 	}
1870 	if ((size_t)len < sizeof(exit_code)) {
1871 		logerrx("%s: truncated read %zd (expected %zu)",
1872 		    __func__, len, sizeof(exit_code));
1873 		eloop_exit(ctx->eloop, EXIT_FAILURE);
1874 		return;
1875 	}
1876 
1877 	if (ctx->options & DHCPCD_FORKED) {
1878 		if (exit_code == EXIT_SUCCESS)
1879 			logdebugx("forked to background");
1880 		eloop_exit(ctx->eloop, exit_code);
1881 	} else
1882 		dhcpcd_signal_cb(exit_code, ctx);
1883 }
1884 
1885 static void
dhcpcd_pidfile_timeout(void * arg)1886 dhcpcd_pidfile_timeout(void *arg)
1887 {
1888 	struct dhcpcd_ctx *ctx = arg;
1889 	pid_t pid;
1890 
1891 	pid = pidfile_read(ctx->pidfile);
1892 
1893 	if(pid == -1)
1894 		eloop_exit(ctx->eloop, EXIT_SUCCESS);
1895 	else if (++ctx->duid_len >= 100) { /* overload duid_len */
1896 		logerrx("pid %d failed to exit", pid);
1897 		eloop_exit(ctx->eloop, EXIT_FAILURE);
1898 	} else
1899 		eloop_timeout_add_msec(ctx->eloop, 100,
1900 		    dhcpcd_pidfile_timeout, ctx);
1901 }
1902 
dup_null(int fd)1903 static int dup_null(int fd)
1904 {
1905 	int fd_null = open(_PATH_DEVNULL, O_WRONLY);
1906 	int err;
1907 
1908 	if (fd_null == -1) {
1909 		logwarn("open %s", _PATH_DEVNULL);
1910 		return -1;
1911 	}
1912 
1913 	if ((err = dup2(fd_null, fd)) == -1)
1914 		logwarn("dup2 %d", fd);
1915 	close(fd_null);
1916 	return err;
1917 }
1918 
1919 int
main(int argc,char ** argv,char ** envp)1920 main(int argc, char **argv, char **envp)
1921 {
1922 	struct dhcpcd_ctx ctx;
1923 	struct ifaddrs *ifaddrs = NULL;
1924 	struct if_options *ifo;
1925 	struct interface *ifp;
1926 	sa_family_t family = AF_UNSPEC;
1927 	int opt, oi = 0, i;
1928 	unsigned int logopts, t;
1929 	ssize_t len;
1930 #if defined(USE_SIGNALS) || !defined(THERE_IS_NO_FORK)
1931 	pid_t pid;
1932 	int fork_fd[2];
1933 #endif
1934 #ifdef USE_SIGNALS
1935 	int sig = 0;
1936 	const char *siga = NULL;
1937 	size_t si;
1938 #endif
1939 
1940 #ifdef SETPROCTITLE_H
1941 	setproctitle_init(argc, argv, envp);
1942 #else
1943 	UNUSED(envp);
1944 #endif
1945 
1946 	/* Test for --help and --version */
1947 	if (argc > 1) {
1948 		if (strcmp(argv[1], "--help") == 0) {
1949 			usage();
1950 			return EXIT_SUCCESS;
1951 		} else if (strcmp(argv[1], "--version") == 0) {
1952 			printf(""PACKAGE" "VERSION"\n%s\n", dhcpcd_copyright);
1953 			printf("Compiled in features:"
1954 #ifdef INET
1955 			" INET"
1956 #endif
1957 #ifdef ARP
1958 			" ARP"
1959 #endif
1960 #ifdef ARPING
1961 			" ARPing"
1962 #endif
1963 #ifdef IPV4LL
1964 			" IPv4LL"
1965 #endif
1966 #ifdef INET6
1967 			" INET6"
1968 #endif
1969 #ifdef DHCP6
1970 			" DHCPv6"
1971 #endif
1972 #ifdef AUTH
1973 			" AUTH"
1974 #endif
1975 #ifdef PRIVSEP
1976 			" PRIVSEP"
1977 #endif
1978 			"\n");
1979 			return EXIT_SUCCESS;
1980 		}
1981 	}
1982 
1983 	memset(&ctx, 0, sizeof(ctx));
1984 	closefrom(STDERR_FILENO + 1);
1985 
1986 	ifo = NULL;
1987 	ctx.cffile = CONFIG;
1988 	ctx.script = UNCONST(dhcpcd_default_script);
1989 	ctx.control_fd = ctx.control_unpriv_fd = ctx.link_fd = -1;
1990 	ctx.pf_inet_fd = -1;
1991 #ifdef PF_LINK
1992 	ctx.pf_link_fd = -1;
1993 #endif
1994 
1995 	TAILQ_INIT(&ctx.control_fds);
1996 #ifdef USE_SIGNALS
1997 	ctx.fork_fd = -1;
1998 #endif
1999 #ifdef PLUGIN_DEV
2000 	ctx.dev_fd = -1;
2001 #endif
2002 #ifdef INET
2003 	ctx.udp_rfd = -1;
2004 	ctx.udp_wfd = -1;
2005 #endif
2006 #if defined(INET6) && !defined(__sun)
2007 	ctx.nd_fd = -1;
2008 #endif
2009 #ifdef DHCP6
2010 	ctx.dhcp6_rfd = -1;
2011 	ctx.dhcp6_wfd = -1;
2012 #endif
2013 #ifdef PRIVSEP
2014 	ctx.ps_log_fd = ctx.ps_log_root_fd = -1;
2015 	TAILQ_INIT(&ctx.ps_processes);
2016 #endif
2017 
2018 	logopts = LOGERR_LOG | LOGERR_LOG_DATE | LOGERR_LOG_PID;
2019 
2020 	/* Ensure we have stdin, stdout and stderr file descriptors.
2021 	 * This is important as we do run scripts which expect these. */
2022 	if (fcntl(STDIN_FILENO,  F_GETFD) == -1)
2023 		dup_null(STDIN_FILENO);
2024 	if (fcntl(STDOUT_FILENO,  F_GETFD) == -1)
2025 		dup_null(STDOUT_FILENO);
2026 	if (fcntl(STDERR_FILENO,  F_GETFD) == -1)
2027 		dup_null(STDERR_FILENO);
2028 	else
2029 		logopts |= LOGERR_ERR;
2030 
2031 	i = 0;
2032 
2033 	while ((opt = getopt_long(argc, argv,
2034 	    ctx.options & DHCPCD_PRINT_PIDFILE ? NOERR_IF_OPTS : IF_OPTS,
2035 	    cf_options, &oi)) != -1)
2036 	{
2037 		switch (opt) {
2038 		case '4':
2039 			family = AF_INET;
2040 			break;
2041 		case '6':
2042 			family = AF_INET6;
2043 			break;
2044 		case 'f':
2045 			ctx.cffile = optarg;
2046 			break;
2047 		case 'j':
2048 			free(ctx.logfile);
2049 			ctx.logfile = strdup(optarg);
2050 			break;
2051 #ifdef USE_SIGNALS
2052 		case 'k':
2053 			sig = SIGALRM;
2054 			siga = "ALRM";
2055 			break;
2056 		case 'n':
2057 			sig = SIGHUP;
2058 			siga = "HUP";
2059 			break;
2060 		case 'q':
2061 			/* -qq disables console output entirely.
2062 			 * This is important for systemd because it logs
2063 			 * both console AND syslog to the same log
2064 			 * resulting in untold confusion. */
2065 			if (logopts & LOGERR_QUIET)
2066 				logopts &= ~LOGERR_ERR;
2067 			else
2068 				logopts |= LOGERR_QUIET;
2069 			break;
2070 		case 'x':
2071 			sig = SIGTERM;
2072 			siga = "TERM";
2073 			break;
2074 		case 'N':
2075 			sig = SIGUSR1;
2076 			siga = "USR1";
2077 			break;
2078 #endif
2079 		case 'P':
2080 			ctx.options |= DHCPCD_PRINT_PIDFILE;
2081 			logopts &= ~(LOGERR_LOG | LOGERR_ERR);
2082 			break;
2083 		case 'T':
2084 			i = 1;
2085 			logopts &= ~LOGERR_LOG;
2086 			break;
2087 		case 'U':
2088 			i = 3;
2089 			break;
2090 		case 'V':
2091 			i = 2;
2092 			break;
2093 		case '?':
2094 			if (ctx.options & DHCPCD_PRINT_PIDFILE)
2095 				continue;
2096 			usage();
2097 			goto exit_failure;
2098 		}
2099 	}
2100 
2101 	if (optind != argc - 1)
2102 		ctx.options |= DHCPCD_MANAGER;
2103 
2104 	logsetopts(logopts);
2105 	logopen(ctx.logfile);
2106 
2107 	ctx.argv = argv;
2108 	ctx.argc = argc;
2109 	ctx.ifc = argc - optind;
2110 	ctx.ifv = argv + optind;
2111 
2112 	rt_init(&ctx);
2113 
2114 	ifo = read_config(&ctx, NULL, NULL, NULL);
2115 	if (ifo == NULL) {
2116 		if (ctx.options & DHCPCD_PRINT_PIDFILE)
2117 			goto printpidfile;
2118 		goto exit_failure;
2119 	}
2120 
2121 	opt = add_options(&ctx, NULL, ifo, argc, argv);
2122 	if (opt != 1) {
2123 		if (ctx.options & DHCPCD_PRINT_PIDFILE)
2124 			goto printpidfile;
2125 		if (opt == 0)
2126 			usage();
2127 		goto exit_failure;
2128 	}
2129 	if (i == 2) {
2130 		printf("Interface options:\n");
2131 		if (optind == argc - 1) {
2132 			free_options(&ctx, ifo);
2133 			ifo = read_config(&ctx, argv[optind], NULL, NULL);
2134 			if (ifo == NULL)
2135 				goto exit_failure;
2136 			add_options(&ctx, NULL, ifo, argc, argv);
2137 		}
2138 		if_printoptions();
2139 #ifdef INET
2140 		if (family == 0 || family == AF_INET) {
2141 			printf("\nDHCPv4 options:\n");
2142 			dhcp_printoptions(&ctx,
2143 			    ifo->dhcp_override, ifo->dhcp_override_len);
2144 		}
2145 #endif
2146 #ifdef INET6
2147 		if (family == 0 || family == AF_INET6) {
2148 			printf("\nND options:\n");
2149 			ipv6nd_printoptions(&ctx,
2150 			    ifo->nd_override, ifo->nd_override_len);
2151 #ifdef DHCP6
2152 			printf("\nDHCPv6 options:\n");
2153 			dhcp6_printoptions(&ctx,
2154 			    ifo->dhcp6_override, ifo->dhcp6_override_len);
2155 #endif
2156 		}
2157 #endif
2158 		goto exit_success;
2159 	}
2160 	ctx.options |= ifo->options;
2161 
2162 	if (i == 1 || i == 3) {
2163 		if (i == 1)
2164 			ctx.options |= DHCPCD_TEST;
2165 		else
2166 			ctx.options |= DHCPCD_DUMPLEASE;
2167 		ctx.options |= DHCPCD_PERSISTENT;
2168 		ctx.options &= ~DHCPCD_DAEMONISE;
2169 	}
2170 
2171 #ifdef THERE_IS_NO_FORK
2172 	ctx.options &= ~DHCPCD_DAEMONISE;
2173 #endif
2174 
2175 	if (ctx.options & DHCPCD_DEBUG)
2176 		logsetopts(logopts | LOGERR_DEBUG);
2177 
2178 	if (!(ctx.options & (DHCPCD_TEST | DHCPCD_DUMPLEASE))) {
2179 printpidfile:
2180 		/* If we have any other args, we should run as a single dhcpcd
2181 		 *  instance for that interface. */
2182 		if (optind == argc - 1 && !(ctx.options & DHCPCD_MANAGER)) {
2183 			const char *per;
2184 			const char *ifname;
2185 
2186 			ifname = *ctx.ifv;
2187 			if (ifname == NULL || strlen(ifname) > IF_NAMESIZE) {
2188 				errno = ifname == NULL ? EINVAL : E2BIG;
2189 				logerr("%s: ", ifname);
2190 				goto exit_failure;
2191 			}
2192 			/* Allow a dhcpcd interface per address family */
2193 			switch(family) {
2194 			case AF_INET:
2195 				per = "-4";
2196 				break;
2197 			case AF_INET6:
2198 				per = "-6";
2199 				break;
2200 			default:
2201 				per = "";
2202 			}
2203 			snprintf(ctx.pidfile, sizeof(ctx.pidfile),
2204 			    PIDFILE, ifname, per, ".");
2205 		} else {
2206 			snprintf(ctx.pidfile, sizeof(ctx.pidfile),
2207 			    PIDFILE, "", "", "");
2208 			ctx.options |= DHCPCD_MANAGER;
2209 
2210 			/*
2211 			 * If we are given any interfaces or a family, we
2212 			 * cannot send a signal as that would impact
2213 			 * other interfaces.
2214 			 */
2215 			if (optind != argc || family != AF_UNSPEC)
2216 				sig = 0;
2217 		}
2218 		if (ctx.options & DHCPCD_PRINT_PIDFILE) {
2219 			printf("%s\n", ctx.pidfile);
2220 			goto exit_success;
2221 		}
2222 	}
2223 
2224 	if (chdir("/") == -1)
2225 		logerr("%s: chdir: /", __func__);
2226 
2227 	/* Freeing allocated addresses from dumping leases can trigger
2228 	 * eloop removals as well, so init here. */
2229 	if ((ctx.eloop = eloop_new()) == NULL) {
2230 		logerr("%s: eloop_init", __func__);
2231 		goto exit_failure;
2232 	}
2233 
2234 #ifdef USE_SIGNALS
2235 	for (si = 0; si < dhcpcd_signals_ignore_len; si++)
2236 		signal(dhcpcd_signals_ignore[si], SIG_IGN);
2237 
2238 	/* Save signal mask, block and redirect signals to our handler */
2239 	eloop_signal_set_cb(ctx.eloop,
2240 	    dhcpcd_signals, dhcpcd_signals_len,
2241 	    dhcpcd_signal_cb, &ctx);
2242 	if (eloop_signal_mask(ctx.eloop, &ctx.sigset) == -1) {
2243 		logerr("%s: eloop_signal_mask", __func__);
2244 		goto exit_failure;
2245 	}
2246 
2247 	if (sig != 0) {
2248 		pid = pidfile_read(ctx.pidfile);
2249 		if (pid != 0 && pid != -1)
2250 			loginfox("sending signal %s to pid %d", siga, pid);
2251 		if (pid == 0 || pid == -1 || kill(pid, sig) != 0) {
2252 			if (pid != 0 && pid != -1 && errno != ESRCH) {
2253 				logerr("kill");
2254 				goto exit_failure;
2255 			}
2256 			unlink(ctx.pidfile);
2257 			/* We can still continue and send the command
2258 			 * via the control socket. */
2259 		} else {
2260 			if (sig == SIGHUP || sig == SIGUSR1)
2261 				goto exit_success;
2262 			/* Spin until it exits */
2263 			loginfox("waiting for pid %d to exit", pid);
2264 			dhcpcd_pidfile_timeout(&ctx);
2265 			goto run_loop;
2266 		}
2267 	}
2268 #endif
2269 
2270 #ifdef HAVE_OPENSSL
2271 	OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS |
2272 	    OPENSSL_INIT_ADD_ALL_DIGESTS | OPENSSL_INIT_LOAD_CONFIG, NULL);
2273 #endif
2274 
2275 #ifdef PRIVSEP
2276 	ps_init(&ctx);
2277 #endif
2278 
2279 #ifndef SMALL
2280 	if (ctx.options & DHCPCD_DUMPLEASE &&
2281 	    ioctl(fileno(stdin), FIONREAD, &i, sizeof(i)) == 0 &&
2282 	    i > 0)
2283 	{
2284 		ctx.options |= DHCPCD_FORKED; /* pretend child process */
2285 #ifdef PRIVSEP
2286 		if (IN_PRIVSEP(&ctx) && ps_managersandbox(&ctx, NULL) == -1)
2287 			goto exit_failure;
2288 #endif
2289 		ifp = calloc(1, sizeof(*ifp));
2290 		if (ifp == NULL) {
2291 			logerr(__func__);
2292 			goto exit_failure;
2293 		}
2294 		ifp->ctx = &ctx;
2295 		ifp->options = ifo;
2296 		switch (family) {
2297 		case AF_INET:
2298 #ifdef INET
2299 			if (dhcp_dump(ifp) == -1)
2300 				goto exit_failure;
2301 			break;
2302 #else
2303 			logerrx("No DHCP support");
2304 			goto exit_failure;
2305 #endif
2306 		case AF_INET6:
2307 #ifdef DHCP6
2308 			if (dhcp6_dump(ifp) == -1)
2309 				goto exit_failure;
2310 			break;
2311 #else
2312 			logerrx("No DHCP6 support");
2313 			goto exit_failure;
2314 #endif
2315 		default:
2316 			logerrx("Family not specified. Please use -4 or -6.");
2317 			goto exit_failure;
2318 		}
2319 		goto exit_success;
2320 	}
2321 #endif
2322 
2323 	/* Try and contact the manager process to send the instruction. */
2324 	if (!(ctx.options & DHCPCD_TEST)) {
2325 		ctx.options |= DHCPCD_FORKED; /* avoid socket unlink */
2326 		if (!(ctx.options & DHCPCD_MANAGER))
2327 			ctx.control_fd = control_open(argv[optind], family,
2328 			    ctx.options & DHCPCD_DUMPLEASE);
2329 		if (!(ctx.options & DHCPCD_MANAGER) && ctx.control_fd == -1)
2330 			ctx.control_fd = control_open(argv[optind], AF_UNSPEC,
2331 			    ctx.options & DHCPCD_DUMPLEASE);
2332 		if (ctx.control_fd == -1)
2333 			ctx.control_fd = control_open(NULL, AF_UNSPEC,
2334 			    ctx.options & DHCPCD_DUMPLEASE);
2335 		if (ctx.control_fd != -1) {
2336 #ifdef PRIVSEP
2337 			if (IN_PRIVSEP(&ctx) &&
2338 			    ps_managersandbox(&ctx, NULL) == -1)
2339 				goto exit_failure;
2340 #endif
2341 			if (!(ctx.options & DHCPCD_DUMPLEASE))
2342 				loginfox("sending commands to dhcpcd process");
2343 			len = control_send(&ctx, argc, argv);
2344 			if (len > 0)
2345 				logdebugx("send OK");
2346 			else {
2347 				logerr("%s: control_send", __func__);
2348 				goto exit_failure;
2349 			}
2350 			if (ctx.options & DHCPCD_DUMPLEASE) {
2351 				if (dhcpcd_readdump(&ctx) == -1) {
2352 					logerr("%s: dhcpcd_readdump", __func__);
2353 					goto exit_failure;
2354 				}
2355 				goto run_loop;
2356 			}
2357 			goto exit_success;
2358 		} else {
2359 			if (errno != ENOENT)
2360 				logerr("%s: control_open", __func__);
2361 			/* If asking dhcpcd to exit and we failed to
2362 			 * send a signal or a message then we
2363 			 * don't proceed past here. */
2364 			if (ctx.options & DHCPCD_DUMPLEASE ||
2365 			    sig == SIGTERM || sig == SIGALRM)
2366 			{
2367 				if (errno == ENOENT)
2368 					logerrx(PACKAGE" is not running");
2369 				goto exit_failure;
2370 			}
2371 			if (errno == EPERM || errno == EACCES)
2372 				goto exit_failure;
2373 		}
2374 		ctx.options &= ~DHCPCD_FORKED;
2375 	}
2376 
2377 	if (!(ctx.options & DHCPCD_TEST)) {
2378 		/* Ensure we have the needed directories */
2379 		if (mkdir(DBDIR, 0750) == -1 && errno != EEXIST)
2380 			logerr("%s: mkdir: %s", __func__, DBDIR);
2381 		if (mkdir(RUNDIR, 0755) == -1 && errno != EEXIST)
2382 			logerr("%s: mkdir: %s", __func__, RUNDIR);
2383 		if ((pid = pidfile_lock(ctx.pidfile)) != 0) {
2384 			if (pid == -1)
2385 				logerr("%s: pidfile_lock: %s",
2386 				    __func__, ctx.pidfile);
2387 			else
2388 				logerrx(PACKAGE
2389 				    " already running on pid %d (%s)",
2390 				    pid, ctx.pidfile);
2391 			goto exit_failure;
2392 		}
2393 	}
2394 
2395 	loginfox(PACKAGE "-" VERSION " starting");
2396 
2397 	// We don't need stdin past this point
2398 	dup_null(STDIN_FILENO);
2399 
2400 #if defined(USE_SIGNALS) && !defined(THERE_IS_NO_FORK)
2401 	if (!(ctx.options & DHCPCD_DAEMONISE))
2402 		goto start_manager;
2403 
2404 	if (xsocketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CXNB, 0, fork_fd) == -1) {
2405 		logerr("socketpair");
2406 		goto exit_failure;
2407 	}
2408 	switch (pid = fork()) {
2409 	case -1:
2410 		logerr("fork");
2411 		goto exit_failure;
2412 	case 0:
2413 		ctx.fork_fd = fork_fd[1];
2414 		close(fork_fd[0]);
2415 #ifdef PRIVSEP_RIGHTS
2416 		if (ps_rights_limit_fd(ctx.fork_fd) == -1) {
2417 			logerr("ps_rights_limit_fdpair");
2418 			goto exit_failure;
2419 		}
2420 #endif
2421 		if (eloop_event_add(ctx.eloop, ctx.fork_fd, ELE_READ,
2422 		    dhcpcd_fork_cb, &ctx) == -1)
2423 			logerr("%s: eloop_event_add", __func__);
2424 
2425 		if (setsid() == -1) {
2426 			logerr("%s: setsid", __func__);
2427 			goto exit_failure;
2428 		}
2429 		/* Ensure we can never get a controlling terminal */
2430 		switch (pid = fork()) {
2431 		case -1:
2432 			logerr("fork");
2433 			goto exit_failure;
2434 		case 0:
2435 			eloop_forked(ctx.eloop);
2436 			break;
2437 		default:
2438 			ctx.options |= DHCPCD_FORKED; /* A lie */
2439 			i = EXIT_SUCCESS;
2440 			goto exit1;
2441 		}
2442 		break;
2443 	default:
2444 		setproctitle("[launcher]");
2445 		ctx.options |= DHCPCD_FORKED | DHCPCD_LAUNCHER;
2446 		ctx.fork_fd = fork_fd[0];
2447 		close(fork_fd[1]);
2448 #ifdef PRIVSEP_RIGHTS
2449 		if (ps_rights_limit_fd(ctx.fork_fd) == -1) {
2450 			logerr("ps_rights_limit_fd");
2451 			goto exit_failure;
2452 		}
2453 #endif
2454 		if (eloop_event_add(ctx.eloop, ctx.fork_fd, ELE_READ,
2455 		    dhcpcd_fork_cb, &ctx) == -1)
2456 			logerr("%s: eloop_event_add", __func__);
2457 
2458 #ifdef PRIVSEP
2459 		if (IN_PRIVSEP(&ctx) && ps_managersandbox(&ctx, NULL) == -1)
2460 			goto exit_failure;
2461 #endif
2462 		goto run_loop;
2463 	}
2464 
2465 #ifdef DEBUG_FD
2466 	loginfox("forkfd %d", ctx.fork_fd);
2467 #endif
2468 
2469 	/* We have now forked, setsid, forked once more.
2470 	 * From this point on, we are the controlling daemon. */
2471 	logdebugx("spawned manager process on PID %d", getpid());
2472 
2473 start_manager:
2474 	ctx.options |= DHCPCD_STARTED;
2475 	if ((pid = pidfile_lock(ctx.pidfile)) != 0) {
2476 		logerr("%s: pidfile_lock %d", __func__, pid);
2477 #ifdef PRIVSEP
2478 		/* privsep has not started ... */
2479 		ctx.options &= ~DHCPCD_PRIVSEP;
2480 #endif
2481 		goto exit_failure;
2482 	}
2483 #endif
2484 
2485 	os_init();
2486 
2487 #if defined(BSD) && defined(INET6)
2488 	/* Disable the kernel RTADV sysctl as early as possible. */
2489 	if (ctx.options & DHCPCD_IPV6 && ctx.options & DHCPCD_IPV6RS)
2490 		if_disable_rtadv();
2491 #endif
2492 
2493 #ifdef PRIVSEP
2494 	if (IN_PRIVSEP(&ctx) && ps_start(&ctx) == -1) {
2495 		logerr("ps_start");
2496 		goto exit_failure;
2497 	}
2498 	if (ctx.options & DHCPCD_FORKED)
2499 		goto run_loop;
2500 #endif
2501 
2502 	if (!(ctx.options & DHCPCD_TEST)) {
2503 		if (control_start(&ctx,
2504 		    ctx.options & DHCPCD_MANAGER ?
2505 		    NULL : argv[optind], family) == -1)
2506 		{
2507 			logerr("%s: control_start", __func__);
2508 			goto exit_failure;
2509 		}
2510 	}
2511 
2512 #ifdef PLUGIN_DEV
2513 	/* Start any dev listening plugin which may want to
2514 	 * change the interface name provided by the kernel */
2515 	if (!IN_PRIVSEP(&ctx) &&
2516 	    (ctx.options & (DHCPCD_MANAGER | DHCPCD_DEV)) ==
2517 	    (DHCPCD_MANAGER | DHCPCD_DEV))
2518 		dev_start(&ctx, dhcpcd_handleinterface);
2519 #endif
2520 
2521 	setproctitle("%s%s%s",
2522 	    ctx.options & DHCPCD_MANAGER ? "[manager]" : argv[optind],
2523 	    ctx.options & DHCPCD_IPV4 ? " [ip4]" : "",
2524 	    ctx.options & DHCPCD_IPV6 ? " [ip6]" : "");
2525 
2526 	if (if_opensockets(&ctx) == -1) {
2527 		logerr("%s: if_opensockets", __func__);
2528 		goto exit_failure;
2529 	}
2530 #ifndef SMALL
2531 	dhcpcd_setlinkrcvbuf(&ctx);
2532 #endif
2533 
2534 	/* Try and create DUID from the machine UUID. */
2535 	dhcpcd_initduid(&ctx, NULL);
2536 
2537 	/* Cache the default vendor option. */
2538 	if (dhcp_vendor(ctx.vendor, sizeof(ctx.vendor)) == -1)
2539 		logerr("dhcp_vendor");
2540 
2541 	/* Start handling kernel messages for interfaces, addresses and
2542 	 * routes. */
2543 	if (eloop_event_add(ctx.eloop, ctx.link_fd, ELE_READ,
2544 	    dhcpcd_handlelink, &ctx) == -1)
2545 		logerr("%s: eloop_event_add", __func__);
2546 
2547 #ifdef PRIVSEP
2548 	if (IN_PRIVSEP(&ctx) && ps_managersandbox(&ctx, "stdio route") == -1)
2549 		goto exit_failure;
2550 #endif
2551 
2552 	/* When running dhcpcd against a single interface, we need to retain
2553 	 * the old behaviour of waiting for an IP address */
2554 	if (ctx.ifc == 1 && !(ctx.options & DHCPCD_BACKGROUND))
2555 		ctx.options |= DHCPCD_WAITIP;
2556 
2557 	ctx.ifaces = if_discover(&ctx, &ifaddrs, ctx.ifc, ctx.ifv);
2558 	if (ctx.ifaces == NULL) {
2559 		logerr("%s: if_discover", __func__);
2560 		goto exit_failure;
2561 	}
2562 	for (i = 0; i < ctx.ifc; i++) {
2563 		if ((ifp = if_find(ctx.ifaces, ctx.ifv[i])) == NULL)
2564 			logerrx("%s: interface not found",
2565 			    ctx.ifv[i]);
2566 		else if (!ifp->active)
2567 			logerrx("%s: interface has an invalid configuration",
2568 			    ctx.ifv[i]);
2569 	}
2570 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2571 		if (ifp->active == IF_ACTIVE_USER)
2572 			break;
2573 	}
2574 
2575 	if (ifp == NULL) {
2576 		if (ctx.ifc == 0) {
2577 			int loglevel;
2578 
2579 			loglevel = ctx.options & DHCPCD_INACTIVE ?
2580 			    LOG_DEBUG : LOG_ERR;
2581 			logmessage(loglevel, "no valid interfaces found");
2582 			dhcpcd_daemonise(&ctx);
2583 		} else
2584 			goto exit_failure;
2585 		if (!(ctx.options & DHCPCD_LINK)) {
2586 			logerrx("aborting as link detection is disabled");
2587 			goto exit_failure;
2588 		}
2589 	}
2590 
2591 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2592 		if (ifp->active)
2593 			dhcpcd_initstate1(ifp, argc, argv, 0);
2594 	}
2595 	if_learnaddrs(&ctx, ctx.ifaces, &ifaddrs);
2596 	if_freeifaddrs(&ctx, &ifaddrs);
2597 	ifaddrs = NULL;
2598 
2599 	if (ctx.options & DHCPCD_BACKGROUND)
2600 		dhcpcd_daemonise(&ctx);
2601 
2602 	opt = 0;
2603 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2604 		if (ifp->active) {
2605 			run_preinit(ifp);
2606 			if (if_is_link_up(ifp))
2607 				opt = 1;
2608 		}
2609 	}
2610 
2611 	if (!(ctx.options & DHCPCD_BACKGROUND)) {
2612 		if (ctx.options & DHCPCD_MANAGER)
2613 			t = ifo->timeout;
2614 		else {
2615 			t = 0;
2616 			TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2617 				if (ifp->active) {
2618 					t = ifp->options->timeout;
2619 					break;
2620 				}
2621 			}
2622 		}
2623 		if (opt == 0 &&
2624 		    ctx.options & DHCPCD_LINK &&
2625 		    !(ctx.options & DHCPCD_WAITIP))
2626 		{
2627 			int loglevel;
2628 
2629 			loglevel = ctx.options & DHCPCD_INACTIVE ?
2630 			    LOG_DEBUG : LOG_WARNING;
2631 			logmessage(loglevel, "no interfaces have a carrier");
2632 			dhcpcd_daemonise(&ctx);
2633 		} else if (t > 0 &&
2634 		    /* Test mode removes the daemonise bit, so check for both */
2635 		    ctx.options & (DHCPCD_DAEMONISE | DHCPCD_TEST))
2636 		{
2637 			eloop_timeout_add_sec(ctx.eloop, t,
2638 			    handle_exit_timeout, &ctx);
2639 		}
2640 	}
2641 	free_options(&ctx, ifo);
2642 	ifo = NULL;
2643 
2644 	TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2645 		if (ifp->active)
2646 			eloop_timeout_add_sec(ctx.eloop, 0,
2647 			    dhcpcd_prestartinterface, ifp);
2648 	}
2649 
2650 run_loop:
2651 	i = eloop_start(ctx.eloop, &ctx.sigset);
2652 	if (i < 0) {
2653 		logerr("%s: eloop_start", __func__);
2654 		goto exit_failure;
2655 	}
2656 	goto exit1;
2657 
2658 exit_success:
2659 	i = EXIT_SUCCESS;
2660 	goto exit1;
2661 
2662 exit_failure:
2663 	i = EXIT_FAILURE;
2664 
2665 exit1:
2666 	if (!(ctx.options & DHCPCD_TEST) && control_stop(&ctx) == -1)
2667 		logerr("%s: control_stop", __func__);
2668 	if_freeifaddrs(&ctx, &ifaddrs);
2669 #ifdef PRIVSEP
2670 	ps_stop(&ctx);
2671 #endif
2672 	/* Free memory and close fd's */
2673 	if (ctx.ifaces) {
2674 		while ((ifp = TAILQ_FIRST(ctx.ifaces))) {
2675 			TAILQ_REMOVE(ctx.ifaces, ifp, next);
2676 			if_free(ifp);
2677 		}
2678 		free(ctx.ifaces);
2679 		ctx.ifaces = NULL;
2680 	}
2681 	free_options(&ctx, ifo);
2682 #ifdef HAVE_OPEN_MEMSTREAM
2683 	if (ctx.script_fp)
2684 		fclose(ctx.script_fp);
2685 #endif
2686 	free(ctx.script_buf);
2687 	free(ctx.script_env);
2688 	rt_dispose(&ctx);
2689 	free(ctx.duid);
2690 	if_closesockets(&ctx);
2691 	free_globals(&ctx);
2692 #ifdef INET6
2693 	ipv6_ctxfree(&ctx);
2694 #endif
2695 #ifdef PLUGIN_DEV
2696 	dev_stop(&ctx);
2697 #endif
2698 	if (ctx.script != dhcpcd_default_script)
2699 		free(ctx.script);
2700 #ifdef PRIVSEP
2701 	if (ps_stopwait(&ctx) != EXIT_SUCCESS)
2702 		i = EXIT_FAILURE;
2703 #endif
2704 	if (ctx.options & DHCPCD_STARTED && !(ctx.options & DHCPCD_FORKED))
2705 		loginfox(PACKAGE " exited");
2706 #ifdef PRIVSEP
2707 	if (ps_root_stop(&ctx) == -1)
2708 		i = EXIT_FAILURE;
2709 	eloop_free(ctx.ps_eloop);
2710 #endif
2711 
2712 #ifdef USE_SIGNALS
2713 	/* If still attached, detach from the launcher */
2714 	if (ctx.options & DHCPCD_STARTED && ctx.fork_fd != -1) {
2715 		if (write(ctx.fork_fd, &i, sizeof(i)) == -1)
2716 			logerr("%s: write", __func__);
2717 	}
2718 #endif
2719 
2720 	eloop_free(ctx.eloop);
2721 	logclose();
2722 	free(ctx.logfile);
2723 	free(ctx.ctl_buf);
2724 #ifdef SETPROCTITLE_H
2725 	setproctitle_fini();
2726 #endif
2727 
2728 #ifdef USE_SIGNALS
2729 	if (ctx.options & (DHCPCD_FORKED | DHCPCD_PRIVSEP))
2730 		_exit(i); /* so atexit won't remove our pidfile */
2731 #endif
2732 	return i;
2733 }
2734