Update to dhcpcd-9.4.1 with the following changes:
[dragonfly.git] / contrib / dhcpcd / src / dhcpcd.c
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * dhcpcd - DHCP client daemon
4  * Copyright (c) 2006-2021 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) 2006-2021 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 const char *dhcpcd_default_script = SCRIPT;
101
102 static void
103 usage(void)
104 {
105
106 printf("usage: "PACKAGE"\t[-146ABbDdEGgHJKLMNPpqTV]\n"
107         "\t\t[-C, --nohook hook] [-c, --script script]\n"
108         "\t\t[-e, --env value] [-F, --fqdn FQDN] [-f, --config file]\n"
109         "\t\t[-h, --hostname hostname] [-I, --clientid clientid]\n"
110         "\t\t[-i, --vendorclassid vendorclassid] [-j, --logfile logfile]\n"
111         "\t\t[-l, --leasetime seconds] [-m, --metric metric]\n"
112         "\t\t[-O, --nooption option] [-o, --option option]\n"
113         "\t\t[-Q, --require option] [-r, --request address]\n"
114         "\t\t[-S, --static value]\n"
115         "\t\t[-s, --inform address[/cidr[/broadcast_address]]]\n [--inform6]"
116         "\t\t[-t, --timeout seconds] [-u, --userclass class]\n"
117         "\t\t[-v, --vendor code, value] [-W, --whitelist address[/cidr]] [-w]\n"
118         "\t\t[--waitip [4 | 6]] [-y, --reboot seconds]\n"
119         "\t\t[-X, --blacklist address[/cidr]] [-Z, --denyinterfaces pattern]\n"
120         "\t\t[-z, --allowinterfaces pattern] [--inactive] [interface] [...]\n"
121         "       "PACKAGE"\t-n, --rebind [interface]\n"
122         "       "PACKAGE"\t-k, --release [interface]\n"
123         "       "PACKAGE"\t-U, --dumplease interface\n"
124         "       "PACKAGE"\t--version\n"
125         "       "PACKAGE"\t-x, --exit [interface]\n");
126 }
127
128 static void
129 free_globals(struct dhcpcd_ctx *ctx)
130 {
131         struct dhcp_opt *opt;
132
133         if (ctx->ifac) {
134                 for (; ctx->ifac > 0; ctx->ifac--)
135                         free(ctx->ifav[ctx->ifac - 1]);
136                 free(ctx->ifav);
137                 ctx->ifav = NULL;
138         }
139         if (ctx->ifdc) {
140                 for (; ctx->ifdc > 0; ctx->ifdc--)
141                         free(ctx->ifdv[ctx->ifdc - 1]);
142                 free(ctx->ifdv);
143                 ctx->ifdv = NULL;
144         }
145         if (ctx->ifcc) {
146                 for (; ctx->ifcc > 0; ctx->ifcc--)
147                         free(ctx->ifcv[ctx->ifcc - 1]);
148                 free(ctx->ifcv);
149                 ctx->ifcv = NULL;
150         }
151
152 #ifdef INET
153         if (ctx->dhcp_opts) {
154                 for (opt = ctx->dhcp_opts;
155                     ctx->dhcp_opts_len > 0;
156                     opt++, ctx->dhcp_opts_len--)
157                         free_dhcp_opt_embenc(opt);
158                 free(ctx->dhcp_opts);
159                 ctx->dhcp_opts = NULL;
160         }
161 #endif
162 #ifdef INET6
163         if (ctx->nd_opts) {
164                 for (opt = ctx->nd_opts;
165                     ctx->nd_opts_len > 0;
166                     opt++, ctx->nd_opts_len--)
167                         free_dhcp_opt_embenc(opt);
168                 free(ctx->nd_opts);
169                 ctx->nd_opts = NULL;
170         }
171 #ifdef DHCP6
172         if (ctx->dhcp6_opts) {
173                 for (opt = ctx->dhcp6_opts;
174                     ctx->dhcp6_opts_len > 0;
175                     opt++, ctx->dhcp6_opts_len--)
176                         free_dhcp_opt_embenc(opt);
177                 free(ctx->dhcp6_opts);
178                 ctx->dhcp6_opts = NULL;
179         }
180 #endif
181 #endif
182         if (ctx->vivso) {
183                 for (opt = ctx->vivso;
184                     ctx->vivso_len > 0;
185                     opt++, ctx->vivso_len--)
186                         free_dhcp_opt_embenc(opt);
187                 free(ctx->vivso);
188                 ctx->vivso = NULL;
189         }
190 }
191
192 static void
193 handle_exit_timeout(void *arg)
194 {
195         struct dhcpcd_ctx *ctx;
196
197         ctx = arg;
198         logerrx("timed out");
199         if (!(ctx->options & DHCPCD_MANAGER)) {
200                 struct interface *ifp;
201
202                 TAILQ_FOREACH(ifp, ctx->ifaces, next) {
203                         if (ifp->active == IF_ACTIVE_USER)
204                                 script_runreason(ifp, "STOPPED");
205                 }
206                 eloop_exit(ctx->eloop, EXIT_FAILURE);
207                 return;
208         }
209         ctx->options |= DHCPCD_NOWAITIP;
210         dhcpcd_daemonise(ctx);
211 }
212
213 static const char *
214 dhcpcd_af(int af)
215 {
216
217         switch (af) {
218         case AF_UNSPEC:
219                 return "IP";
220         case AF_INET:
221                 return "IPv4";
222         case AF_INET6:
223                 return "IPv6";
224         default:
225                 return NULL;
226         }
227 }
228
229 int
230 dhcpcd_ifafwaiting(const struct interface *ifp)
231 {
232         unsigned long long opts;
233         bool foundany = false;
234
235         if (ifp->active != IF_ACTIVE_USER)
236                 return AF_MAX;
237
238 #define DHCPCD_WAITALL  (DHCPCD_WAITIP4 | DHCPCD_WAITIP6)
239         opts = ifp->options->options;
240 #ifdef INET
241         if (opts & DHCPCD_WAITIP4 ||
242             (opts & DHCPCD_WAITIP && !(opts & DHCPCD_WAITALL)))
243         {
244                 bool foundaddr = ipv4_hasaddr(ifp);
245
246                 if (opts & DHCPCD_WAITIP4 && !foundaddr)
247                         return AF_INET;
248                 if (foundaddr)
249                         foundany = true;
250         }
251 #endif
252 #ifdef INET6
253         if (opts & DHCPCD_WAITIP6 ||
254             (opts & DHCPCD_WAITIP && !(opts & DHCPCD_WAITALL)))
255         {
256                 bool foundaddr = ipv6_hasaddr(ifp);
257
258                 if (opts & DHCPCD_WAITIP6 && !foundaddr)
259                         return AF_INET;
260                 if (foundaddr)
261                         foundany = true;
262         }
263 #endif
264
265         if (opts & DHCPCD_WAITIP && !(opts & DHCPCD_WAITALL) && !foundany)
266                 return AF_UNSPEC;
267         return AF_MAX;
268 }
269
270 int
271 dhcpcd_afwaiting(const struct dhcpcd_ctx *ctx)
272 {
273         unsigned long long opts;
274         const struct interface *ifp;
275         int af;
276
277         if (!(ctx->options & DHCPCD_WAITOPTS))
278                 return AF_MAX;
279
280         opts = ctx->options;
281         TAILQ_FOREACH(ifp, ctx->ifaces, next) {
282 #ifdef INET
283                 if (opts & (DHCPCD_WAITIP | DHCPCD_WAITIP4) &&
284                     ipv4_hasaddr(ifp))
285                         opts &= ~(DHCPCD_WAITIP | DHCPCD_WAITIP4);
286 #endif
287 #ifdef INET6
288                 if (opts & (DHCPCD_WAITIP | DHCPCD_WAITIP6) &&
289                     ipv6_hasaddr(ifp))
290                         opts &= ~(DHCPCD_WAITIP | DHCPCD_WAITIP6);
291 #endif
292                 if (!(opts & DHCPCD_WAITOPTS))
293                         break;
294         }
295         if (opts & DHCPCD_WAITIP)
296                 af = AF_UNSPEC;
297         else if (opts & DHCPCD_WAITIP4)
298                 af = AF_INET;
299         else if (opts & DHCPCD_WAITIP6)
300                 af = AF_INET6;
301         else
302                 return AF_MAX;
303         return af;
304 }
305
306 static int
307 dhcpcd_ipwaited(struct dhcpcd_ctx *ctx)
308 {
309         struct interface *ifp;
310         int af;
311
312         TAILQ_FOREACH(ifp, ctx->ifaces, next) {
313                 if ((af = dhcpcd_ifafwaiting(ifp)) != AF_MAX) {
314                         logdebugx("%s: waiting for an %s address",
315                             ifp->name, dhcpcd_af(af));
316                         return 0;
317                 }
318         }
319
320         if ((af = dhcpcd_afwaiting(ctx)) != AF_MAX) {
321                 logdebugx("waiting for an %s address",
322                     dhcpcd_af(af));
323                 return 0;
324         }
325
326         return 1;
327 }
328
329 /* Returns the pid of the child, otherwise 0. */
330 void
331 dhcpcd_daemonise(struct dhcpcd_ctx *ctx)
332 {
333 #ifdef THERE_IS_NO_FORK
334         eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx);
335         errno = ENOSYS;
336         return;
337 #else
338         int i;
339         unsigned int logopts = loggetopts();
340
341         if (ctx->options & DHCPCD_DAEMONISE &&
342             !(ctx->options & (DHCPCD_DAEMONISED | DHCPCD_NOWAITIP)))
343         {
344                 if (!dhcpcd_ipwaited(ctx))
345                         return;
346         }
347
348         if (ctx->options & DHCPCD_ONESHOT) {
349                 loginfox("exiting due to oneshot");
350                 eloop_exit(ctx->eloop, EXIT_SUCCESS);
351                 return;
352         }
353
354         eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx);
355         if (ctx->options & DHCPCD_DAEMONISED ||
356             !(ctx->options & DHCPCD_DAEMONISE))
357                 return;
358
359         /* Don't use loginfo because this makes no sense in a log. */
360         if (!(logopts & LOGERR_QUIET) && ctx->stderr_valid)
361                 (void)fprintf(stderr,
362                     "forked to background, child pid %d\n", getpid());
363         i = EXIT_SUCCESS;
364         if (write(ctx->fork_fd, &i, sizeof(i)) == -1)
365                 logerr("write");
366         ctx->options |= DHCPCD_DAEMONISED;
367         eloop_event_delete(ctx->eloop, ctx->fork_fd);
368         close(ctx->fork_fd);
369         ctx->fork_fd = -1;
370
371         /*
372          * Stop writing to stderr.
373          * On the happy path, only the manager process writes to stderr,
374          * so this just stops wasting fprintf calls to nowhere.
375          * All other calls - ie errors in privsep processes or script output,
376          * will error when printing.
377          * If we *really* want to fix that, then we need to suck
378          * stderr/stdout in the manager process and either disacrd it or pass
379          * it to the launcher process and then to stderr.
380          */
381         logopts &= ~LOGERR_ERR;
382         logsetopts(logopts);
383 #endif
384 }
385
386 static void
387 dhcpcd_drop(struct interface *ifp, int stop)
388 {
389
390 #ifdef DHCP6
391         dhcp6_drop(ifp, stop ? NULL : "EXPIRE6");
392 #endif
393 #ifdef INET6
394         ipv6nd_drop(ifp);
395         ipv6_drop(ifp);
396 #endif
397 #ifdef IPV4LL
398         ipv4ll_drop(ifp);
399 #endif
400 #ifdef INET
401         dhcp_drop(ifp, stop ? "STOP" : "EXPIRE");
402 #endif
403 #ifdef ARP
404         arp_drop(ifp);
405 #endif
406 #if !defined(DHCP6) && !defined(DHCP)
407         UNUSED(stop);
408 #endif
409 }
410
411 static void
412 stop_interface(struct interface *ifp, const char *reason)
413 {
414         struct dhcpcd_ctx *ctx;
415
416         ctx = ifp->ctx;
417         loginfox("%s: removing interface", ifp->name);
418         ifp->options->options |= DHCPCD_STOPPING;
419
420         dhcpcd_drop(ifp, 1);
421         script_runreason(ifp, reason == NULL ? "STOPPED" : reason);
422
423         /* Delete all timeouts for the interfaces */
424         eloop_q_timeout_delete(ctx->eloop, ELOOP_QUEUE_ALL, NULL, ifp);
425
426         /* De-activate the interface */
427         ifp->active = IF_INACTIVE;
428         ifp->options->options &= ~DHCPCD_STOPPING;
429
430         if (!(ctx->options & (DHCPCD_MANAGER | DHCPCD_TEST)))
431                 eloop_exit(ctx->eloop, EXIT_FAILURE);
432 }
433
434 static void
435 configure_interface1(struct interface *ifp)
436 {
437         struct if_options *ifo = ifp->options;
438
439         /* Do any platform specific configuration */
440         if_conf(ifp);
441
442         /* If we want to release a lease, we can't really persist the
443          * address either. */
444         if (ifo->options & DHCPCD_RELEASE)
445                 ifo->options &= ~DHCPCD_PERSISTENT;
446
447         if (ifp->flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) {
448                 ifo->options &= ~DHCPCD_ARP;
449                 if (!(ifp->flags & IFF_MULTICAST))
450                         ifo->options &= ~DHCPCD_IPV6RS;
451                 if (!(ifo->options & (DHCPCD_INFORM | DHCPCD_WANTDHCP)))
452                         ifo->options |= DHCPCD_STATIC;
453         }
454
455         if (ifo->metric != -1)
456                 ifp->metric = (unsigned int)ifo->metric;
457
458 #ifdef INET6
459         /* We want to setup INET6 on the interface as soon as possible. */
460         if (ifp->active == IF_ACTIVE_USER &&
461             ifo->options & DHCPCD_IPV6 &&
462             !(ifp->ctx->options & (DHCPCD_DUMPLEASE | DHCPCD_TEST)))
463         {
464                 /* If not doing any DHCP, disable the RDNSS requirement. */
465                 if (!(ifo->options & (DHCPCD_DHCP | DHCPCD_DHCP6)))
466                         ifo->options &= ~DHCPCD_IPV6RA_REQRDNSS;
467                 if_setup_inet6(ifp);
468         }
469 #endif
470
471         if (!(ifo->options & DHCPCD_IAID)) {
472                 /*
473                  * An IAID is for identifying a unqiue interface within
474                  * the client. It is 4 bytes long. Working out a default
475                  * value is problematic.
476                  *
477                  * Interface name and number are not stable
478                  * between different OS's. Some OS's also cannot make
479                  * up their mind what the interface should be called
480                  * (yes, udev, I'm looking at you).
481                  * Also, the name could be longer than 4 bytes.
482                  * Also, with pluggable interfaces the name and index
483                  * could easily get swapped per actual interface.
484                  *
485                  * The MAC address is 6 bytes long, the final 3
486                  * being unique to the manufacturer and the initial 3
487                  * being unique to the organisation which makes it.
488                  * We could use the last 4 bytes of the MAC address
489                  * as the IAID as it's the most stable part given the
490                  * above, but equally it's not guaranteed to be
491                  * unique.
492                  *
493                  * Given the above, and our need to reliably work
494                  * between reboots without persitent storage,
495                  * generating the IAID from the MAC address is the only
496                  * logical default.
497                  * Saying that, if a VLANID has been specified then we
498                  * can use that. It's possible that different interfaces
499                  * can have the same VLANID, but this is no worse than
500                  * generating the IAID from the duplicate MAC address.
501                  *
502                  * dhclient uses the last 4 bytes of the MAC address.
503                  * dibbler uses an increamenting counter.
504                  * wide-dhcpv6 uses 0 or a configured value.
505                  * odhcp6c uses 1.
506                  * Windows 7 uses the first 3 bytes of the MAC address
507                  * and an unknown byte.
508                  * dhcpcd-6.1.0 and earlier used the interface name,
509                  * falling back to interface index if name > 4.
510                  */
511                 if (ifp->vlanid != 0) {
512                         uint32_t vlanid;
513
514                         /* Maximal VLANID is 4095, so prefix with 0xff
515                          * so we don't conflict with an interface index. */
516                         vlanid = htonl(ifp->vlanid | 0xff000000);
517                         memcpy(ifo->iaid, &vlanid, sizeof(vlanid));
518                 } else if (ifo->options & DHCPCD_ANONYMOUS)
519                         memset(ifo->iaid, 0, sizeof(ifo->iaid));
520                 else if (ifp->hwlen >= sizeof(ifo->iaid)) {
521                         memcpy(ifo->iaid,
522                             ifp->hwaddr + ifp->hwlen - sizeof(ifo->iaid),
523                             sizeof(ifo->iaid));
524                 } else {
525                         uint32_t len;
526
527                         len = (uint32_t)strlen(ifp->name);
528                         if (len <= sizeof(ifo->iaid)) {
529                                 memcpy(ifo->iaid, ifp->name, len);
530                                 if (len < sizeof(ifo->iaid))
531                                         memset(ifo->iaid + len, 0,
532                                             sizeof(ifo->iaid) - len);
533                         } else {
534                                 /* IAID is the same size as a uint32_t */
535                                 len = htonl(ifp->index);
536                                 memcpy(ifo->iaid, &len, sizeof(ifo->iaid));
537                         }
538                 }
539                 ifo->options |= DHCPCD_IAID;
540         }
541
542 #ifdef DHCP6
543         if (ifo->ia_len == 0 && ifo->options & DHCPCD_IPV6 &&
544             ifp->name[0] != '\0')
545         {
546                 ifo->ia = malloc(sizeof(*ifo->ia));
547                 if (ifo->ia == NULL)
548                         logerr(__func__);
549                 else {
550                         ifo->ia_len = 1;
551                         ifo->ia->ia_type = D6_OPTION_IA_NA;
552                         memcpy(ifo->ia->iaid, ifo->iaid, sizeof(ifo->iaid));
553                         memset(&ifo->ia->addr, 0, sizeof(ifo->ia->addr));
554 #ifndef SMALL
555                         ifo->ia->sla = NULL;
556                         ifo->ia->sla_len = 0;
557 #endif
558                 }
559         } else {
560                 size_t i;
561
562                 for (i = 0; i < ifo->ia_len; i++) {
563                         if (!ifo->ia[i].iaid_set) {
564                                 memcpy(&ifo->ia[i].iaid, ifo->iaid,
565                                     sizeof(ifo->ia[i].iaid));
566                                 ifo->ia[i].iaid_set = 1;
567                         }
568                 }
569         }
570 #endif
571
572         /* If root is network mounted, we don't want to kill the connection
573          * if the DHCP server goes the way of the dodo OR dhcpcd is rebooting
574          * and the lease file has expired. */
575         if (is_root_local() == 0)
576                 ifo->options |= DHCPCD_LASTLEASE_EXTEND;
577 }
578
579 int
580 dhcpcd_selectprofile(struct interface *ifp, const char *profile)
581 {
582         struct if_options *ifo;
583         char pssid[PROFILE_LEN];
584
585         if (ifp->ssid_len) {
586                 ssize_t r;
587
588                 r = print_string(pssid, sizeof(pssid), OT_ESCSTRING,
589                     ifp->ssid, ifp->ssid_len);
590                 if (r == -1) {
591                         logerr(__func__);
592                         pssid[0] = '\0';
593                 }
594         } else
595                 pssid[0] = '\0';
596         ifo = read_config(ifp->ctx, ifp->name, pssid, profile);
597         if (ifo == NULL) {
598                 logdebugx("%s: no profile %s", ifp->name, profile);
599                 return -1;
600         }
601         if (profile != NULL) {
602                 strlcpy(ifp->profile, profile, sizeof(ifp->profile));
603                 loginfox("%s: selected profile %s", ifp->name, profile);
604         } else
605                 *ifp->profile = '\0';
606
607         free_options(ifp->ctx, ifp->options);
608         ifp->options = ifo;
609         if (profile) {
610                 add_options(ifp->ctx, ifp->name, ifp->options,
611                     ifp->ctx->argc, ifp->ctx->argv);
612                 configure_interface1(ifp);
613         }
614         return 1;
615 }
616
617 static void
618 configure_interface(struct interface *ifp, int argc, char **argv,
619     unsigned long long options)
620 {
621         time_t old;
622
623         old = ifp->options ? ifp->options->mtime : 0;
624         dhcpcd_selectprofile(ifp, NULL);
625         if (ifp->options == NULL) {
626                 /* dhcpcd cannot continue with this interface. */
627                 ifp->active = IF_INACTIVE;
628                 return;
629         }
630         add_options(ifp->ctx, ifp->name, ifp->options, argc, argv);
631         ifp->options->options |= options;
632         configure_interface1(ifp);
633
634         /* If the mtime has changed drop any old lease */
635         if (old != 0 && ifp->options->mtime != old) {
636                 logwarnx("%s: config file changed, expiring leases",
637                     ifp->name);
638                 dhcpcd_drop(ifp, 0);
639         }
640 }
641
642 static void
643 dhcpcd_initstate2(struct interface *ifp, unsigned long long options)
644 {
645         struct if_options *ifo;
646
647         if (options) {
648                 if ((ifo = default_config(ifp->ctx)) == NULL) {
649                         logerr(__func__);
650                         return;
651                 }
652                 ifo->options |= options;
653                 free(ifp->options);
654                 ifp->options = ifo;
655         } else
656                 ifo = ifp->options;
657
658 #ifdef INET6
659         if (ifo->options & DHCPCD_IPV6 && ipv6_init(ifp->ctx) == -1) {
660                 logerr(__func__);
661                 ifo->options &= ~DHCPCD_IPV6;
662         }
663 #endif
664 }
665
666 static void
667 dhcpcd_initstate1(struct interface *ifp, int argc, char **argv,
668     unsigned long long options)
669 {
670
671         configure_interface(ifp, argc, argv, options);
672         if (ifp->active)
673                 dhcpcd_initstate2(ifp, 0);
674 }
675
676 static void
677 dhcpcd_initstate(struct interface *ifp, unsigned long long options)
678 {
679
680         dhcpcd_initstate1(ifp, ifp->ctx->argc, ifp->ctx->argv, options);
681 }
682
683 static void
684 dhcpcd_reportssid(struct interface *ifp)
685 {
686         char pssid[IF_SSIDLEN * 4];
687
688         if (print_string(pssid, sizeof(pssid), OT_ESCSTRING,
689             ifp->ssid, ifp->ssid_len) == -1)
690         {
691                 logerr(__func__);
692                 return;
693         }
694
695         loginfox("%s: connected to Access Point: %s", ifp->name, pssid);
696 }
697
698 static void
699 dhcpcd_nocarrier_roaming(struct interface *ifp)
700 {
701
702         loginfox("%s: carrier lost - roaming", ifp->name);
703
704 #ifdef ARP
705         arp_drop(ifp);
706 #endif
707 #ifdef INET
708         dhcp_abort(ifp);
709 #endif
710 #ifdef DHCP6
711         dhcp6_abort(ifp);
712 #endif
713
714         rt_build(ifp->ctx, AF_UNSPEC);
715         script_runreason(ifp, "NOCARRIER_ROAMING");
716 }
717
718 void
719 dhcpcd_handlecarrier(struct interface *ifp, int carrier, unsigned int flags)
720 {
721         bool was_link_up = if_is_link_up(ifp);
722         bool was_roaming = if_roaming(ifp);
723
724         ifp->carrier = carrier;
725         ifp->flags = flags;
726
727         if (!if_is_link_up(ifp)) {
728                 if (!ifp->active || (!was_link_up && !was_roaming))
729                         return;
730
731                 /*
732                  * If the interface is roaming (generally on wireless)
733                  * then while we are not up, we are not down either.
734                  * Preserve the network state until we either disconnect
735                  * or re-connect.
736                  */
737                 if (!ifp->options->randomise_hwaddr && if_roaming(ifp)) {
738                         dhcpcd_nocarrier_roaming(ifp);
739                         return;
740                 }
741
742                 loginfox("%s: carrier lost", ifp->name);
743                 script_runreason(ifp, "NOCARRIER");
744                 dhcpcd_drop(ifp, 0);
745
746                 if (ifp->options->randomise_hwaddr) {
747                         bool is_up = ifp->flags & IFF_UP;
748
749                         if (is_up)
750                                 if_down(ifp);
751                         if (if_randomisemac(ifp) == -1 && errno != ENXIO)
752                                 logerr(__func__);
753                         if (is_up)
754                                 if_up(ifp);
755                 }
756
757                 return;
758         }
759
760         /*
761          * At this point carrier is NOT DOWN and we have IFF_UP.
762          * We should treat LINK_UNKNOWN as up as the driver may not support
763          * link state changes.
764          * The consideration of any other information about carrier should
765          * be handled in the OS specific if_carrier() function.
766          */
767         if (was_link_up)
768                 return;
769
770         if (ifp->active) {
771                 if (carrier == LINK_UNKNOWN)
772                         loginfox("%s: carrier unknown, assuming up", ifp->name);
773                 else
774                         loginfox("%s: carrier acquired", ifp->name);
775         }
776
777 #if !defined(__linux__) && !defined(__NetBSD__)
778         /* BSD does not emit RTM_NEWADDR or RTM_CHGADDR when the
779          * hardware address changes so we have to go
780          * through the disovery process to work it out. */
781         dhcpcd_handleinterface(ifp->ctx, 0, ifp->name);
782 #endif
783
784         if (ifp->wireless) {
785                 uint8_t ossid[IF_SSIDLEN];
786                 size_t olen;
787
788                 olen = ifp->ssid_len;
789                 memcpy(ossid, ifp->ssid, ifp->ssid_len);
790                 if_getssid(ifp);
791
792                 /* If we changed SSID network, drop leases */
793                 if ((ifp->ssid_len != olen ||
794                     memcmp(ifp->ssid, ossid, ifp->ssid_len)) && ifp->active)
795                 {
796                         dhcpcd_reportssid(ifp);
797                         dhcpcd_drop(ifp, 0);
798 #ifdef IPV4LL
799                         ipv4ll_reset(ifp);
800 #endif
801                 }
802         }
803
804         if (!ifp->active)
805                 return;
806
807         dhcpcd_initstate(ifp, 0);
808         script_runreason(ifp, "CARRIER");
809
810 #ifdef INET6
811         /* Set any IPv6 Routers we remembered to expire faster than they
812          * would normally as we maybe on a new network. */
813         ipv6nd_startexpire(ifp);
814 #ifdef IPV6_MANAGETEMPADDR
815         /* RFC4941 Section 3.5 */
816         ipv6_regentempaddrs(ifp);
817 #endif
818 #endif
819
820         dhcpcd_startinterface(ifp);
821 }
822
823 static void
824 warn_iaid_conflict(struct interface *ifp, uint16_t ia_type, uint8_t *iaid)
825 {
826         struct interface *ifn;
827 #ifdef INET6
828         size_t i;
829         struct if_ia *ia;
830 #endif
831
832         TAILQ_FOREACH(ifn, ifp->ctx->ifaces, next) {
833                 if (ifn == ifp || !ifn->active)
834                         continue;
835                 if (ifn->options->options & DHCPCD_ANONYMOUS)
836                         continue;
837                 if (ia_type == 0 &&
838                     memcmp(ifn->options->iaid, iaid,
839                     sizeof(ifn->options->iaid)) == 0)
840                         break;
841 #ifdef INET6
842                 for (i = 0; i < ifn->options->ia_len; i++) {
843                         ia = &ifn->options->ia[i];
844                         if (ia->ia_type == ia_type &&
845                             memcmp(ia->iaid, iaid, sizeof(ia->iaid)) == 0)
846                                 break;
847                 }
848 #endif
849         }
850
851         /* This is only a problem if the interfaces are on the same network. */
852         if (ifn)
853                 logerrx("%s: IAID conflicts with one assigned to %s",
854                     ifp->name, ifn->name);
855 }
856
857 static void
858 dhcpcd_initduid(struct dhcpcd_ctx *ctx, struct interface *ifp)
859 {
860         char buf[DUID_LEN * 3];
861
862         if (ctx->duid != NULL) {
863                 if (ifp == NULL)
864                         goto log;
865                 return;
866         }
867
868         duid_init(ctx, ifp);
869         if (ctx->duid == NULL)
870                 return;
871
872 log:
873         loginfox("DUID %s",
874             hwaddr_ntoa(ctx->duid, ctx->duid_len, buf, sizeof(buf)));
875 }
876
877 void
878 dhcpcd_startinterface(void *arg)
879 {
880         struct interface *ifp = arg;
881         struct if_options *ifo = ifp->options;
882
883         if (ifo->options & DHCPCD_LINK && !if_is_link_up(ifp)) {
884                 loginfox("%s: waiting for carrier", ifp->name);
885                 return;
886         }
887
888         if (ifo->options & (DHCPCD_DUID | DHCPCD_IPV6) &&
889             !(ifo->options & DHCPCD_ANONYMOUS))
890         {
891                 char buf[sizeof(ifo->iaid) * 3];
892 #ifdef INET6
893                 size_t i;
894                 struct if_ia *ia;
895 #endif
896
897                 /* Try and init DUID from the interface hardware address */
898                 dhcpcd_initduid(ifp->ctx, ifp);
899
900                 /* Report IAIDs */
901                 loginfox("%s: IAID %s", ifp->name,
902                     hwaddr_ntoa(ifo->iaid, sizeof(ifo->iaid),
903                     buf, sizeof(buf)));
904                 warn_iaid_conflict(ifp, 0, ifo->iaid);
905
906 #ifdef INET6
907                 for (i = 0; i < ifo->ia_len; i++) {
908                         ia = &ifo->ia[i];
909                         if (memcmp(ifo->iaid, ia->iaid, sizeof(ifo->iaid))) {
910                                 loginfox("%s: IA type %u IAID %s",
911                                     ifp->name, ia->ia_type,
912                                     hwaddr_ntoa(ia->iaid, sizeof(ia->iaid),
913                                     buf, sizeof(buf)));
914                                 warn_iaid_conflict(ifp, ia->ia_type, ia->iaid);
915                         }
916                 }
917 #endif
918         }
919
920 #ifdef INET6
921         if (ifo->options & DHCPCD_IPV6 && ipv6_start(ifp) == -1) {
922                 logerr("%s: ipv6_start", ifp->name);
923                 ifo->options &= ~DHCPCD_IPV6;
924         }
925
926         if (ifo->options & DHCPCD_IPV6) {
927                 if (ifp->active == IF_ACTIVE_USER) {
928                         ipv6_startstatic(ifp);
929
930                         if (ifo->options & DHCPCD_IPV6RS)
931                                 ipv6nd_startrs(ifp);
932                 }
933
934 #ifdef DHCP6
935                 /* DHCPv6 could be turned off, but the interface
936                  * is still delegated to. */
937                 if (ifp->active)
938                         dhcp6_find_delegates(ifp);
939
940                 if (ifo->options & DHCPCD_DHCP6) {
941                         if (ifp->active == IF_ACTIVE_USER) {
942                                 enum DH6S d6_state;
943
944                                 if (ifo->options & DHCPCD_IA_FORCED)
945                                         d6_state = DH6S_INIT;
946                                 else if (ifo->options & DHCPCD_INFORM6)
947                                         d6_state = DH6S_INFORM;
948                                 else
949                                         d6_state = DH6S_CONFIRM;
950                                 if (dhcp6_start(ifp, d6_state) == -1)
951                                         logerr("%s: dhcp6_start", ifp->name);
952                         }
953                 }
954 #endif
955         }
956 #endif
957
958 #ifdef INET
959         if (ifo->options & DHCPCD_IPV4 && ifp->active == IF_ACTIVE_USER) {
960                 /* Ensure we have an IPv4 state before starting DHCP */
961                 if (ipv4_getstate(ifp) != NULL)
962                         dhcp_start(ifp);
963         }
964 #endif
965 }
966
967 static void
968 dhcpcd_prestartinterface(void *arg)
969 {
970         struct interface *ifp = arg;
971         struct dhcpcd_ctx *ctx = ifp->ctx;
972         bool randmac_down;
973
974         if (ifp->carrier <= LINK_DOWN &&
975             ifp->options->randomise_hwaddr &&
976             ifp->flags & IFF_UP)
977         {
978                 if_down(ifp);
979                 randmac_down = true;
980         } else
981                 randmac_down = false;
982
983         if ((!(ctx->options & DHCPCD_MANAGER) ||
984             ifp->options->options & DHCPCD_IF_UP || randmac_down) &&
985             !(ifp->flags & IFF_UP))
986         {
987                 if (ifp->options->randomise_hwaddr &&
988                     if_randomisemac(ifp) == -1)
989                         logerr(__func__);
990                 if (if_up(ifp) == -1)
991                         logerr(__func__);
992         }
993
994         dhcpcd_startinterface(ifp);
995 }
996
997 static void
998 run_preinit(struct interface *ifp)
999 {
1000
1001         if (ifp->ctx->options & DHCPCD_TEST)
1002                 return;
1003
1004         script_runreason(ifp, "PREINIT");
1005         if (ifp->wireless && if_is_link_up(ifp))
1006                 dhcpcd_reportssid(ifp);
1007         if (ifp->options->options & DHCPCD_LINK && ifp->carrier != LINK_UNKNOWN)
1008                 script_runreason(ifp,
1009                     ifp->carrier == LINK_UP ? "CARRIER" : "NOCARRIER");
1010 }
1011
1012 void
1013 dhcpcd_activateinterface(struct interface *ifp, unsigned long long options)
1014 {
1015
1016         if (ifp->active)
1017                 return;
1018
1019         ifp->active = IF_ACTIVE;
1020         dhcpcd_initstate2(ifp, options);
1021
1022         /* It's possible we might not have been able to load
1023          * a config. */
1024         if (!ifp->active)
1025                 return;
1026
1027         configure_interface1(ifp);
1028         run_preinit(ifp);
1029         dhcpcd_prestartinterface(ifp);
1030 }
1031
1032 int
1033 dhcpcd_handleinterface(void *arg, int action, const char *ifname)
1034 {
1035         struct dhcpcd_ctx *ctx = arg;
1036         struct ifaddrs *ifaddrs;
1037         struct if_head *ifs;
1038         struct interface *ifp, *iff;
1039         const char * const argv[] = { ifname };
1040         int e;
1041
1042         if (action == -1) {
1043                 ifp = if_find(ctx->ifaces, ifname);
1044                 if (ifp == NULL) {
1045                         errno = ESRCH;
1046                         return -1;
1047                 }
1048                 if (ifp->active) {
1049                         logdebugx("%s: interface departed", ifp->name);
1050                         stop_interface(ifp, "DEPARTED");
1051                 }
1052                 TAILQ_REMOVE(ctx->ifaces, ifp, next);
1053                 if_free(ifp);
1054                 return 0;
1055         }
1056
1057         ifs = if_discover(ctx, &ifaddrs, -1, UNCONST(argv));
1058         if (ifs == NULL) {
1059                 logerr(__func__);
1060                 return -1;
1061         }
1062
1063         ifp = if_find(ifs, ifname);
1064         if (ifp == NULL) {
1065                 /* This can happen if an interface is quickly added
1066                  * and then removed. */
1067                 errno = ENOENT;
1068                 e = -1;
1069                 goto out;
1070         }
1071         e = 1;
1072
1073         /* Check if we already have the interface */
1074         iff = if_find(ctx->ifaces, ifp->name);
1075
1076         if (iff != NULL) {
1077                 if (iff->active)
1078                         logdebugx("%s: interface updated", iff->name);
1079                 /* The flags and hwaddr could have changed */
1080                 iff->flags = ifp->flags;
1081                 iff->hwlen = ifp->hwlen;
1082                 if (ifp->hwlen != 0)
1083                         memcpy(iff->hwaddr, ifp->hwaddr, iff->hwlen);
1084         } else {
1085                 TAILQ_REMOVE(ifs, ifp, next);
1086                 TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next);
1087                 if (ifp->active) {
1088                         logdebugx("%s: interface added", ifp->name);
1089                         dhcpcd_initstate(ifp, 0);
1090                         run_preinit(ifp);
1091                 }
1092                 iff = ifp;
1093         }
1094
1095         if (action > 0) {
1096                 if_learnaddrs(ctx, ifs, &ifaddrs);
1097                 if (iff->active)
1098                         dhcpcd_prestartinterface(iff);
1099         }
1100
1101 out:
1102         /* Free our discovered list */
1103         while ((ifp = TAILQ_FIRST(ifs))) {
1104                 TAILQ_REMOVE(ifs, ifp, next);
1105                 if_free(ifp);
1106         }
1107         free(ifs);
1108
1109         return e;
1110 }
1111
1112 static void
1113 dhcpcd_handlelink(void *arg)
1114 {
1115         struct dhcpcd_ctx *ctx = arg;
1116
1117         if (if_handlelink(ctx) == -1) {
1118                 if (errno == ENOBUFS || errno == ENOMEM) {
1119                         dhcpcd_linkoverflow(ctx);
1120                         return;
1121                 }
1122                 if (errno != ENOTSUP)
1123                         logerr(__func__);
1124         }
1125 }
1126
1127 static void
1128 dhcpcd_checkcarrier(void *arg)
1129 {
1130         struct interface *ifp0 = arg, *ifp;
1131
1132         ifp = if_find(ifp0->ctx->ifaces, ifp0->name);
1133         if (ifp == NULL || ifp->carrier == ifp0->carrier)
1134                 return;
1135
1136         dhcpcd_handlecarrier(ifp, ifp0->carrier, ifp0->flags);
1137         if_free(ifp0);
1138 }
1139
1140 #ifndef SMALL
1141 static void
1142 dhcpcd_setlinkrcvbuf(struct dhcpcd_ctx *ctx)
1143 {
1144         socklen_t socklen;
1145
1146         if (ctx->link_rcvbuf == 0)
1147                 return;
1148
1149         logdebugx("setting route socket receive buffer size to %d bytes",
1150             ctx->link_rcvbuf);
1151
1152         socklen = sizeof(ctx->link_rcvbuf);
1153         if (setsockopt(ctx->link_fd, SOL_SOCKET,
1154             SO_RCVBUF, &ctx->link_rcvbuf, socklen) == -1)
1155                 logerr(__func__);
1156 }
1157 #endif
1158
1159 static void
1160 dhcpcd_runprestartinterface(void *arg)
1161 {
1162         struct interface *ifp = arg;
1163
1164         run_preinit(ifp);
1165         dhcpcd_prestartinterface(ifp);
1166 }
1167
1168 void
1169 dhcpcd_linkoverflow(struct dhcpcd_ctx *ctx)
1170 {
1171         socklen_t socklen;
1172         int rcvbuflen;
1173         char buf[2048];
1174         ssize_t rlen;
1175         size_t rcnt;
1176         struct if_head *ifaces;
1177         struct ifaddrs *ifaddrs;
1178         struct interface *ifp, *ifn, *ifp1;
1179
1180         socklen = sizeof(rcvbuflen);
1181         if (getsockopt(ctx->link_fd, SOL_SOCKET,
1182             SO_RCVBUF, &rcvbuflen, &socklen) == -1) {
1183                 logerr("%s: getsockopt", __func__);
1184                 rcvbuflen = 0;
1185         }
1186 #ifdef __linux__
1187         else
1188                 rcvbuflen /= 2;
1189 #endif
1190
1191         logerrx("route socket overflowed (rcvbuflen %d)"
1192             " - learning interface state", rcvbuflen);
1193
1194         /* Drain the socket.
1195          * We cannot open a new one due to privsep. */
1196         rcnt = 0;
1197         do {
1198                 rlen = read(ctx->link_fd, buf, sizeof(buf));
1199                 if (++rcnt % 1000 == 0)
1200                         logwarnx("drained %zu messages", rcnt);
1201         } while (rlen != -1 || errno == ENOBUFS || errno == ENOMEM);
1202         if (rcnt % 1000 != 0)
1203                 logwarnx("drained %zu messages", rcnt);
1204
1205         /* Work out the current interfaces. */
1206         ifaces = if_discover(ctx, &ifaddrs, ctx->ifc, ctx->ifv);
1207         if (ifaces == NULL) {
1208                 logerr(__func__);
1209                 return;
1210         }
1211
1212         /* Punt departed interfaces */
1213         TAILQ_FOREACH_SAFE(ifp, ctx->ifaces, next, ifn) {
1214                 if (if_find(ifaces, ifp->name) != NULL)
1215                         continue;
1216                 dhcpcd_handleinterface(ctx, -1, ifp->name);
1217         }
1218
1219         /* Add new interfaces */
1220         while ((ifp = TAILQ_FIRST(ifaces)) != NULL ) {
1221                 TAILQ_REMOVE(ifaces, ifp, next);
1222                 ifp1 = if_find(ctx->ifaces, ifp->name);
1223                 if (ifp1 != NULL) {
1224                         /* If the interface already exists,
1225                          * check carrier state.
1226                          * dhcpcd_checkcarrier will free ifp. */
1227                         eloop_timeout_add_sec(ctx->eloop, 0,
1228                             dhcpcd_checkcarrier, ifp);
1229                         continue;
1230                 }
1231                 TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next);
1232                 if (ifp->active) {
1233                         dhcpcd_initstate(ifp, 0);
1234                         eloop_timeout_add_sec(ctx->eloop, 0,
1235                             dhcpcd_runprestartinterface, ifp);
1236                 }
1237         }
1238         free(ifaces);
1239
1240         /* Update address state. */
1241         if_markaddrsstale(ctx->ifaces);
1242         if_learnaddrs(ctx, ctx->ifaces, &ifaddrs);
1243         if_deletestaleaddrs(ctx->ifaces);
1244 }
1245
1246 void
1247 dhcpcd_handlehwaddr(struct interface *ifp,
1248     uint16_t hwtype, const void *hwaddr, uint8_t hwlen)
1249 {
1250         char buf[sizeof(ifp->hwaddr) * 3];
1251
1252         if (hwaddr == NULL || !if_valid_hwaddr(hwaddr, hwlen))
1253                 hwlen = 0;
1254
1255         if (hwlen > sizeof(ifp->hwaddr)) {
1256                 errno = ENOBUFS;
1257                 logerr("%s: %s", __func__, ifp->name);
1258                 return;
1259         }
1260
1261         if (ifp->hwtype != hwtype) {
1262                 if (ifp->active)
1263                         loginfox("%s: hardware address type changed"
1264                             " from %d to %d", ifp->name, ifp->hwtype, hwtype);
1265                 ifp->hwtype = hwtype;
1266         }
1267
1268         if (ifp->hwlen == hwlen &&
1269             (hwlen == 0 || memcmp(ifp->hwaddr, hwaddr, hwlen) == 0))
1270                 return;
1271
1272         if (ifp->active) {
1273                 loginfox("%s: old hardware address: %s", ifp->name,
1274                     hwaddr_ntoa(ifp->hwaddr, ifp->hwlen, buf, sizeof(buf)));
1275                 loginfox("%s: new hardware address: %s", ifp->name,
1276                     hwaddr_ntoa(hwaddr, hwlen, buf, sizeof(buf)));
1277         }
1278         ifp->hwlen = hwlen;
1279         if (hwaddr != NULL)
1280                 memcpy(ifp->hwaddr, hwaddr, hwlen);
1281 }
1282
1283 static void
1284 if_reboot(struct interface *ifp, int argc, char **argv)
1285 {
1286 #ifdef INET
1287         unsigned long long oldopts;
1288
1289         oldopts = ifp->options->options;
1290 #endif
1291         script_runreason(ifp, "RECONFIGURE");
1292         dhcpcd_initstate1(ifp, argc, argv, 0);
1293 #ifdef INET
1294         dhcp_reboot_newopts(ifp, oldopts);
1295 #endif
1296 #ifdef DHCP6
1297         dhcp6_reboot(ifp);
1298 #endif
1299         dhcpcd_prestartinterface(ifp);
1300 }
1301
1302 static void
1303 reload_config(struct dhcpcd_ctx *ctx)
1304 {
1305         struct if_options *ifo;
1306
1307         free_globals(ctx);
1308         if ((ifo = read_config(ctx, NULL, NULL, NULL)) == NULL)
1309                 return;
1310         add_options(ctx, NULL, ifo, ctx->argc, ctx->argv);
1311         /* We need to preserve these options. */
1312         if (ctx->options & DHCPCD_STARTED)
1313                 ifo->options |= DHCPCD_STARTED;
1314         if (ctx->options & DHCPCD_MANAGER)
1315                 ifo->options |= DHCPCD_MANAGER;
1316         if (ctx->options & DHCPCD_DAEMONISED)
1317                 ifo->options |= DHCPCD_DAEMONISED;
1318         if (ctx->options & DHCPCD_PRIVSEP)
1319                 ifo->options |= DHCPCD_PRIVSEP;
1320         ctx->options = ifo->options;
1321         free_options(ctx, ifo);
1322 }
1323
1324 static void
1325 reconf_reboot(struct dhcpcd_ctx *ctx, int action, int argc, char **argv, int oi)
1326 {
1327         int i;
1328         struct interface *ifp;
1329
1330         TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1331                 for (i = oi; i < argc; i++) {
1332                         if (strcmp(ifp->name, argv[i]) == 0)
1333                                 break;
1334                 }
1335                 if (oi != argc && i == argc)
1336                         continue;
1337                 if (ifp->active == IF_ACTIVE_USER) {
1338                         if (action)
1339                                 if_reboot(ifp, argc, argv);
1340 #ifdef INET
1341                         else
1342                                 ipv4_applyaddr(ifp);
1343 #endif
1344                 } else if (i != argc) {
1345                         ifp->active = IF_ACTIVE_USER;
1346                         dhcpcd_initstate1(ifp, argc, argv, 0);
1347                         run_preinit(ifp);
1348                         dhcpcd_prestartinterface(ifp);
1349                 }
1350         }
1351 }
1352
1353 static void
1354 stop_all_interfaces(struct dhcpcd_ctx *ctx, unsigned long long opts)
1355 {
1356         struct interface *ifp;
1357
1358         ctx->options |= DHCPCD_EXITING;
1359         if (ctx->ifaces == NULL)
1360                 return;
1361
1362         /* Drop the last interface first */
1363         TAILQ_FOREACH_REVERSE(ifp, ctx->ifaces, if_head, next) {
1364                 if (!ifp->active)
1365                         continue;
1366                 ifp->options->options |= opts;
1367                 if (ifp->options->options & DHCPCD_RELEASE)
1368                         ifp->options->options &= ~DHCPCD_PERSISTENT;
1369                 ifp->options->options |= DHCPCD_EXITING;
1370                 stop_interface(ifp, NULL);
1371         }
1372 }
1373
1374 static void
1375 dhcpcd_ifrenew(struct interface *ifp)
1376 {
1377
1378         if (!ifp->active)
1379                 return;
1380
1381         if (ifp->options->options & DHCPCD_LINK && !if_is_link_up(ifp))
1382                 return;
1383
1384 #ifdef INET
1385         dhcp_renew(ifp);
1386 #endif
1387 #ifdef INET6
1388 #define DHCPCD_RARENEW (DHCPCD_IPV6 | DHCPCD_IPV6RS)
1389         if ((ifp->options->options & DHCPCD_RARENEW) == DHCPCD_RARENEW)
1390                 ipv6nd_startrs(ifp);
1391 #endif
1392 #ifdef DHCP6
1393         dhcp6_renew(ifp);
1394 #endif
1395 }
1396
1397 static void
1398 dhcpcd_renew(struct dhcpcd_ctx *ctx)
1399 {
1400         struct interface *ifp;
1401
1402         TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1403                 dhcpcd_ifrenew(ifp);
1404         }
1405 }
1406
1407 #ifdef USE_SIGNALS
1408 #define sigmsg "received %s, %s"
1409 static void
1410 dhcpcd_signal_cb(int sig, void *arg)
1411 {
1412         struct dhcpcd_ctx *ctx = arg;
1413         unsigned long long opts;
1414         int exit_code;
1415
1416         if (ctx->options & DHCPCD_DUMPLEASE) {
1417                 eloop_exit(ctx->eloop, EXIT_FAILURE);
1418                 return;
1419         }
1420
1421         if (sig != SIGCHLD && ctx->options & DHCPCD_FORKED) {
1422                 if (sig != SIGHUP &&
1423                     write(ctx->fork_fd, &sig, sizeof(sig)) == -1)
1424                         logerr("%s: write", __func__);
1425                 return;
1426         }
1427
1428         opts = 0;
1429         exit_code = EXIT_FAILURE;
1430         switch (sig) {
1431         case SIGINT:
1432                 loginfox(sigmsg, "SIGINT", "stopping");
1433                 break;
1434         case SIGTERM:
1435                 loginfox(sigmsg, "SIGTERM", "stopping");
1436                 exit_code = EXIT_SUCCESS;
1437                 break;
1438         case SIGALRM:
1439                 loginfox(sigmsg, "SIGALRM", "releasing");
1440                 opts |= DHCPCD_RELEASE;
1441                 exit_code = EXIT_SUCCESS;
1442                 break;
1443         case SIGHUP:
1444                 loginfox(sigmsg, "SIGHUP", "rebinding");
1445                 reload_config(ctx);
1446                 /* Preserve any options passed on the commandline
1447                  * when we were started. */
1448                 reconf_reboot(ctx, 1, ctx->argc, ctx->argv,
1449                     ctx->argc - ctx->ifc);
1450                 return;
1451         case SIGUSR1:
1452                 loginfox(sigmsg, "SIGUSR1", "renewing");
1453                 dhcpcd_renew(ctx);
1454                 return;
1455         case SIGUSR2:
1456                 loginfox(sigmsg, "SIGUSR2", "reopening log");
1457 #ifdef PRIVSEP
1458                 if (IN_PRIVSEP(ctx)) {
1459                         if (ps_root_logreopen(ctx) == -1)
1460                                 logerr("ps_root_logreopen");
1461                         return;
1462                 }
1463 #endif
1464                 if (logopen(ctx->logfile) == -1)
1465                         logerr("logopen");
1466                 return;
1467         case SIGCHLD:
1468                 while (waitpid(-1, NULL, WNOHANG) > 0)
1469                         ;
1470                 return;
1471         default:
1472                 logerrx("received signal %d but don't know what to do with it",
1473                     sig);
1474                 return;
1475         }
1476
1477         if (!(ctx->options & DHCPCD_TEST))
1478                 stop_all_interfaces(ctx, opts);
1479         eloop_exit(ctx->eloop, exit_code);
1480 }
1481 #endif
1482
1483 int
1484 dhcpcd_handleargs(struct dhcpcd_ctx *ctx, struct fd_list *fd,
1485     int argc, char **argv)
1486 {
1487         struct interface *ifp;
1488         unsigned long long opts;
1489         int opt, oi, do_reboot, do_renew, af = AF_UNSPEC;
1490         size_t len, l, nifaces;
1491         char *tmp, *p;
1492
1493         /* Special commands for our control socket
1494          * as the other end should be blocking until it gets the
1495          * expected reply we should be safely able just to change the
1496          * write callback on the fd */
1497         /* Make any change here in privsep-control.c as well. */
1498         if (strcmp(*argv, "--version") == 0) {
1499                 return control_queue(fd, UNCONST(VERSION),
1500                     strlen(VERSION) + 1);
1501         } else if (strcmp(*argv, "--getconfigfile") == 0) {
1502                 return control_queue(fd, UNCONST(fd->ctx->cffile),
1503                     strlen(fd->ctx->cffile) + 1);
1504         } else if (strcmp(*argv, "--getinterfaces") == 0) {
1505                 optind = argc = 0;
1506                 goto dumplease;
1507         } else if (strcmp(*argv, "--listen") == 0) {
1508                 fd->flags |= FD_LISTEN;
1509                 return 0;
1510         }
1511
1512         /* Log the command */
1513         len = 1;
1514         for (opt = 0; opt < argc; opt++)
1515                 len += strlen(argv[opt]) + 1;
1516         tmp = malloc(len);
1517         if (tmp == NULL)
1518                 return -1;
1519         p = tmp;
1520         for (opt = 0; opt < argc; opt++) {
1521                 l = strlen(argv[opt]);
1522                 strlcpy(p, argv[opt], len);
1523                 len -= l + 1;
1524                 p += l;
1525                 *p++ = ' ';
1526         }
1527         *--p = '\0';
1528         loginfox("control command: %s", tmp);
1529         free(tmp);
1530
1531         optind = 0;
1532         oi = 0;
1533         opts = 0;
1534         do_reboot = do_renew = 0;
1535         while ((opt = getopt_long(argc, argv, IF_OPTS, cf_options, &oi)) != -1)
1536         {
1537                 switch (opt) {
1538                 case 'g':
1539                         /* Assumed if below not set */
1540                         break;
1541                 case 'k':
1542                         opts |= DHCPCD_RELEASE;
1543                         break;
1544                 case 'n':
1545                         do_reboot = 1;
1546                         break;
1547                 case 'p':
1548                         opts |= DHCPCD_PERSISTENT;
1549                         break;
1550                 case 'x':
1551                         opts |= DHCPCD_EXITING;
1552                         break;
1553                 case 'N':
1554                         do_renew = 1;
1555                         break;
1556                 case 'U':
1557                         opts |= DHCPCD_DUMPLEASE;
1558                         break;
1559                 case '4':
1560                         af = AF_INET;
1561                         break;
1562                 case '6':
1563                         af = AF_INET6;
1564                         break;
1565                 }
1566         }
1567
1568         if (opts & DHCPCD_DUMPLEASE) {
1569                 ctx->options |= DHCPCD_DUMPLEASE;
1570 dumplease:
1571                 nifaces = 0;
1572                 TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1573                         if (!ifp->active)
1574                                 continue;
1575                         for (oi = optind; oi < argc; oi++) {
1576                                 if (strcmp(ifp->name, argv[oi]) == 0)
1577                                         break;
1578                         }
1579                         if (optind == argc || oi < argc) {
1580                                 opt = send_interface(NULL, ifp, af);
1581                                 if (opt == -1)
1582                                         goto dumperr;
1583                                 nifaces += (size_t)opt;
1584                         }
1585                 }
1586                 if (write(fd->fd, &nifaces, sizeof(nifaces)) != sizeof(nifaces))
1587                         goto dumperr;
1588                 TAILQ_FOREACH(ifp, ctx->ifaces, next) {
1589                         if (!ifp->active)
1590                                 continue;
1591                         for (oi = optind; oi < argc; oi++) {
1592                                 if (strcmp(ifp->name, argv[oi]) == 0)
1593                                         break;
1594                         }
1595                         if (optind == argc || oi < argc) {
1596                                 if (send_interface(fd, ifp, af) == -1)
1597                                         goto dumperr;
1598                         }
1599                 }
1600                 ctx->options &= ~DHCPCD_DUMPLEASE;
1601                 return 0;
1602 dumperr:
1603                 ctx->options &= ~DHCPCD_DUMPLEASE;
1604                 return -1;
1605         }
1606
1607         /* Only privileged users can control dhcpcd via the socket. */
1608         if (fd->flags & FD_UNPRIV) {
1609                 errno = EPERM;
1610                 return -1;
1611         }
1612
1613         if (opts & (DHCPCD_EXITING | DHCPCD_RELEASE)) {
1614                 if (optind == argc) {
1615                         stop_all_interfaces(ctx, opts);
1616                         eloop_exit(ctx->eloop, EXIT_SUCCESS);
1617                         return 0;
1618                 }
1619                 for (oi = optind; oi < argc; oi++) {
1620                         if ((ifp = if_find(ctx->ifaces, argv[oi])) == NULL)
1621                                 continue;
1622                         if (!ifp->active)
1623                                 continue;
1624                         ifp->options->options |= opts;
1625                         if (opts & DHCPCD_RELEASE)
1626                                 ifp->options->options &= ~DHCPCD_PERSISTENT;
1627                         stop_interface(ifp, NULL);
1628                 }
1629                 return 0;
1630         }
1631
1632         if (do_renew) {
1633                 if (optind == argc) {
1634                         dhcpcd_renew(ctx);
1635                         return 0;
1636                 }
1637                 for (oi = optind; oi < argc; oi++) {
1638                         if ((ifp = if_find(ctx->ifaces, argv[oi])) == NULL)
1639                                 continue;
1640                         dhcpcd_ifrenew(ifp);
1641                 }
1642                 return 0;
1643         }
1644
1645         reload_config(ctx);
1646         /* XXX: Respect initial commandline options? */
1647         reconf_reboot(ctx, do_reboot, argc, argv, optind - 1);
1648         return 0;
1649 }
1650
1651 static void dhcpcd_readdump1(void *);
1652
1653 static void
1654 dhcpcd_readdump2(void *arg)
1655 {
1656         struct dhcpcd_ctx *ctx = arg;
1657         ssize_t len;
1658         int exit_code = EXIT_FAILURE;
1659
1660         len = read(ctx->control_fd, ctx->ctl_buf + ctx->ctl_bufpos,
1661             ctx->ctl_buflen - ctx->ctl_bufpos);
1662         if (len == -1) {
1663                 logerr(__func__);
1664                 goto finished;
1665         } else if (len == 0)
1666                 goto finished;
1667         if ((size_t)len + ctx->ctl_bufpos != ctx->ctl_buflen) {
1668                 ctx->ctl_bufpos += (size_t)len;
1669                 return;
1670         }
1671
1672         if (ctx->ctl_buf[ctx->ctl_buflen - 1] != '\0') /* unlikely */
1673                 ctx->ctl_buf[ctx->ctl_buflen - 1] = '\0';
1674         script_dump(ctx->ctl_buf, ctx->ctl_buflen);
1675         fflush(stdout);
1676         if (--ctx->ctl_extra != 0) {
1677                 putchar('\n');
1678                 eloop_event_add(ctx->eloop, ctx->control_fd,
1679                     dhcpcd_readdump1, ctx);
1680                 return;
1681         }
1682         exit_code = EXIT_SUCCESS;
1683
1684 finished:
1685         shutdown(ctx->control_fd, SHUT_RDWR);
1686         eloop_exit(ctx->eloop, exit_code);
1687 }
1688
1689 static void
1690 dhcpcd_readdump1(void *arg)
1691 {
1692         struct dhcpcd_ctx *ctx = arg;
1693         ssize_t len;
1694
1695         len = read(ctx->control_fd, &ctx->ctl_buflen, sizeof(ctx->ctl_buflen));
1696         if (len != sizeof(ctx->ctl_buflen)) {
1697                 if (len != -1)
1698                         errno = EINVAL;
1699                 goto err;
1700         }
1701         if (ctx->ctl_buflen > SSIZE_MAX) {
1702                 errno = ENOBUFS;
1703                 goto err;
1704         }
1705
1706         free(ctx->ctl_buf);
1707         ctx->ctl_buf = malloc(ctx->ctl_buflen);
1708         if (ctx->ctl_buf == NULL)
1709                 goto err;
1710
1711         ctx->ctl_bufpos = 0;
1712         eloop_event_add(ctx->eloop, ctx->control_fd,
1713             dhcpcd_readdump2, ctx);
1714         return;
1715
1716 err:
1717         logerr(__func__);
1718         eloop_exit(ctx->eloop, EXIT_FAILURE);
1719 }
1720
1721 static void
1722 dhcpcd_readdump0(void *arg)
1723 {
1724         struct dhcpcd_ctx *ctx = arg;
1725         ssize_t len;
1726
1727         len = read(ctx->control_fd, &ctx->ctl_extra, sizeof(ctx->ctl_extra));
1728         if (len != sizeof(ctx->ctl_extra)) {
1729                 if (len != -1)
1730                         errno = EINVAL;
1731                 logerr(__func__);
1732                 eloop_exit(ctx->eloop, EXIT_FAILURE);
1733                 return;
1734         }
1735
1736         if (ctx->ctl_extra == 0) {
1737                 eloop_exit(ctx->eloop, EXIT_SUCCESS);
1738                 return;
1739         }
1740
1741         eloop_event_add(ctx->eloop, ctx->control_fd,
1742             dhcpcd_readdump1, ctx);
1743 }
1744
1745 static void
1746 dhcpcd_readdumptimeout(void *arg)
1747 {
1748         struct dhcpcd_ctx *ctx = arg;
1749
1750         logerrx(__func__);
1751         eloop_exit(ctx->eloop, EXIT_FAILURE);
1752 }
1753
1754 static int
1755 dhcpcd_readdump(struct dhcpcd_ctx *ctx)
1756 {
1757
1758         ctx->options |= DHCPCD_FORKED;
1759         if (eloop_timeout_add_sec(ctx->eloop, 5,
1760             dhcpcd_readdumptimeout, ctx) == -1)
1761                 return -1;
1762         return eloop_event_add(ctx->eloop, ctx->control_fd,
1763             dhcpcd_readdump0, ctx);
1764 }
1765
1766 static void
1767 dhcpcd_fork_cb(void *arg)
1768 {
1769         struct dhcpcd_ctx *ctx = arg;
1770         int exit_code;
1771         ssize_t len;
1772
1773         len = read(ctx->fork_fd, &exit_code, sizeof(exit_code));
1774         if (len == -1) {
1775                 logerr(__func__);
1776                 exit_code = EXIT_FAILURE;
1777         } else if ((size_t)len < sizeof(exit_code)) {
1778                 logerrx("%s: truncated read %zd (expected %zu)",
1779                     __func__, len, sizeof(exit_code));
1780                 exit_code = EXIT_FAILURE;
1781         }
1782         if (ctx->options & DHCPCD_FORKED)
1783                 eloop_exit(ctx->eloop, exit_code);
1784         else
1785                 dhcpcd_signal_cb(exit_code, ctx);
1786 }
1787
1788 static void
1789 dhcpcd_stderr_cb(void *arg)
1790 {
1791         struct dhcpcd_ctx *ctx = arg;
1792         char log[BUFSIZ];
1793         ssize_t len;
1794
1795         len = read(ctx->stderr_fd, log, sizeof(log));
1796         if (len == -1) {
1797                 if (errno != ECONNRESET)
1798                         logerr(__func__);
1799                 return;
1800         }
1801
1802         log[len] = '\0';
1803         fprintf(stderr, "%s", log);
1804 }
1805
1806 int
1807 main(int argc, char **argv, char **envp)
1808 {
1809         struct dhcpcd_ctx ctx;
1810         struct ifaddrs *ifaddrs = NULL;
1811         struct if_options *ifo;
1812         struct interface *ifp;
1813         sa_family_t family = AF_UNSPEC;
1814         int opt, oi = 0, i;
1815         unsigned int logopts, t;
1816         ssize_t len;
1817 #if defined(USE_SIGNALS) || !defined(THERE_IS_NO_FORK)
1818         pid_t pid;
1819         int fork_fd[2], stderr_fd[2];
1820 #endif
1821 #ifdef USE_SIGNALS
1822         int sig = 0;
1823         const char *siga = NULL;
1824         size_t si;
1825 #endif
1826
1827 #ifdef SETPROCTITLE_H
1828         setproctitle_init(argc, argv, envp);
1829 #else
1830         UNUSED(envp);
1831 #endif
1832
1833         /* Test for --help and --version */
1834         if (argc > 1) {
1835                 if (strcmp(argv[1], "--help") == 0) {
1836                         usage();
1837                         return EXIT_SUCCESS;
1838                 } else if (strcmp(argv[1], "--version") == 0) {
1839                         printf(""PACKAGE" "VERSION"\n%s\n", dhcpcd_copyright);
1840                         printf("Compiled in features:"
1841 #ifdef INET
1842                         " INET"
1843 #endif
1844 #ifdef ARP
1845                         " ARP"
1846 #endif
1847 #ifdef ARPING
1848                         " ARPing"
1849 #endif
1850 #ifdef IPV4LL
1851                         " IPv4LL"
1852 #endif
1853 #ifdef INET6
1854                         " INET6"
1855 #endif
1856 #ifdef DHCP6
1857                         " DHCPv6"
1858 #endif
1859 #ifdef AUTH
1860                         " AUTH"
1861 #endif
1862 #ifdef PRIVSEP
1863                         " PRIVSEP"
1864 #endif
1865                         "\n");
1866                         return EXIT_SUCCESS;
1867                 }
1868         }
1869
1870         memset(&ctx, 0, sizeof(ctx));
1871
1872         ifo = NULL;
1873         ctx.cffile = CONFIG;
1874         ctx.script = UNCONST(dhcpcd_default_script);
1875         ctx.control_fd = ctx.control_unpriv_fd = ctx.link_fd = -1;
1876         ctx.pf_inet_fd = -1;
1877 #ifdef PF_LINK
1878         ctx.pf_link_fd = -1;
1879 #endif
1880
1881         TAILQ_INIT(&ctx.control_fds);
1882 #ifdef USE_SIGNALS
1883         ctx.fork_fd = -1;
1884 #endif
1885 #ifdef PLUGIN_DEV
1886         ctx.dev_fd = -1;
1887 #endif
1888 #ifdef INET
1889         ctx.udp_rfd = -1;
1890         ctx.udp_wfd = -1;
1891 #endif
1892 #if defined(INET6) && !defined(__sun)
1893         ctx.nd_fd = -1;
1894 #endif
1895 #ifdef DHCP6
1896         ctx.dhcp6_rfd = -1;
1897         ctx.dhcp6_wfd = -1;
1898 #endif
1899 #ifdef PRIVSEP
1900         ctx.ps_root_fd = ctx.ps_log_fd = ctx.ps_data_fd = -1;
1901         ctx.ps_inet_fd = ctx.ps_control_fd = -1;
1902         TAILQ_INIT(&ctx.ps_processes);
1903 #endif
1904
1905         /* Check our streams for validity */
1906         ctx.stdin_valid =  fcntl(STDIN_FILENO,  F_GETFD) != -1;
1907         ctx.stdout_valid = fcntl(STDOUT_FILENO, F_GETFD) != -1;
1908         ctx.stderr_valid = fcntl(STDERR_FILENO, F_GETFD) != -1;
1909
1910         logopts = LOGERR_LOG | LOGERR_LOG_DATE | LOGERR_LOG_PID;
1911         if (ctx.stderr_valid)
1912                 logopts |= LOGERR_ERR;
1913
1914         i = 0;
1915
1916         while ((opt = getopt_long(argc, argv,
1917             ctx.options & DHCPCD_PRINT_PIDFILE ? NOERR_IF_OPTS : IF_OPTS,
1918             cf_options, &oi)) != -1)
1919         {
1920                 switch (opt) {
1921                 case '4':
1922                         family = AF_INET;
1923                         break;
1924                 case '6':
1925                         family = AF_INET6;
1926                         break;
1927                 case 'f':
1928                         ctx.cffile = optarg;
1929                         break;
1930                 case 'j':
1931                         free(ctx.logfile);
1932                         ctx.logfile = strdup(optarg);
1933                         break;
1934 #ifdef USE_SIGNALS
1935                 case 'k':
1936                         sig = SIGALRM;
1937                         siga = "ALRM";
1938                         break;
1939                 case 'n':
1940                         sig = SIGHUP;
1941                         siga = "HUP";
1942                         break;
1943                 case 'g':
1944                 case 'p':
1945                         /* Force going via command socket as we're
1946                          * out of user definable signals. */
1947                         i = 4;
1948                         break;
1949                 case 'q':
1950                         /* -qq disables console output entirely.
1951                          * This is important for systemd because it logs
1952                          * both console AND syslog to the same log
1953                          * resulting in untold confusion. */
1954                         if (logopts & LOGERR_QUIET)
1955                                 logopts &= ~LOGERR_ERR;
1956                         else
1957                                 logopts |= LOGERR_QUIET;
1958                         break;
1959                 case 'x':
1960                         sig = SIGTERM;
1961                         siga = "TERM";
1962                         break;
1963                 case 'N':
1964                         sig = SIGUSR1;
1965                         siga = "USR1";
1966                         break;
1967 #endif
1968                 case 'P':
1969                         ctx.options |= DHCPCD_PRINT_PIDFILE;
1970                         logopts &= ~(LOGERR_LOG | LOGERR_ERR);
1971                         break;
1972                 case 'T':
1973                         i = 1;
1974                         logopts &= ~LOGERR_LOG;
1975                         break;
1976                 case 'U':
1977                         i = 3;
1978                         break;
1979                 case 'V':
1980                         i = 2;
1981                         break;
1982                 case '?':
1983                         if (ctx.options & DHCPCD_PRINT_PIDFILE)
1984                                 continue;
1985                         usage();
1986                         goto exit_failure;
1987                 }
1988         }
1989
1990         if (optind != argc - 1)
1991                 ctx.options |= DHCPCD_MANAGER;
1992
1993         logsetopts(logopts);
1994         logopen(ctx.logfile);
1995
1996         ctx.argv = argv;
1997         ctx.argc = argc;
1998         ctx.ifc = argc - optind;
1999         ctx.ifv = argv + optind;
2000
2001         rt_init(&ctx);
2002
2003         ifo = read_config(&ctx, NULL, NULL, NULL);
2004         if (ifo == NULL) {
2005                 if (ctx.options & DHCPCD_PRINT_PIDFILE)
2006                         goto printpidfile;
2007                 goto exit_failure;
2008         }
2009
2010         opt = add_options(&ctx, NULL, ifo, argc, argv);
2011         if (opt != 1) {
2012                 if (ctx.options & DHCPCD_PRINT_PIDFILE)
2013                         goto printpidfile;
2014                 if (opt == 0)
2015                         usage();
2016                 goto exit_failure;
2017         }
2018         if (i == 2) {
2019                 printf("Interface options:\n");
2020                 if (optind == argc - 1) {
2021                         free_options(&ctx, ifo);
2022                         ifo = read_config(&ctx, argv[optind], NULL, NULL);
2023                         if (ifo == NULL)
2024                                 goto exit_failure;
2025                         add_options(&ctx, NULL, ifo, argc, argv);
2026                 }
2027                 if_printoptions();
2028 #ifdef INET
2029                 if (family == 0 || family == AF_INET) {
2030                         printf("\nDHCPv4 options:\n");
2031                         dhcp_printoptions(&ctx,
2032                             ifo->dhcp_override, ifo->dhcp_override_len);
2033                 }
2034 #endif
2035 #ifdef INET6
2036                 if (family == 0 || family == AF_INET6) {
2037                         printf("\nND options:\n");
2038                         ipv6nd_printoptions(&ctx,
2039                             ifo->nd_override, ifo->nd_override_len);
2040 #ifdef DHCP6
2041                         printf("\nDHCPv6 options:\n");
2042                         dhcp6_printoptions(&ctx,
2043                             ifo->dhcp6_override, ifo->dhcp6_override_len);
2044 #endif
2045                 }
2046 #endif
2047                 goto exit_success;
2048         }
2049         ctx.options |= ifo->options;
2050
2051         if (i == 1 || i == 3) {
2052                 if (i == 1)
2053                         ctx.options |= DHCPCD_TEST;
2054                 else
2055                         ctx.options |= DHCPCD_DUMPLEASE;
2056                 ctx.options |= DHCPCD_PERSISTENT;
2057                 ctx.options &= ~DHCPCD_DAEMONISE;
2058         }
2059
2060 #ifdef THERE_IS_NO_FORK
2061         ctx.options &= ~DHCPCD_DAEMONISE;
2062 #endif
2063
2064         if (ctx.options & DHCPCD_DEBUG)
2065                 logsetopts(logopts | LOGERR_DEBUG);
2066
2067         if (!(ctx.options & (DHCPCD_TEST | DHCPCD_DUMPLEASE))) {
2068 printpidfile:
2069                 /* If we have any other args, we should run as a single dhcpcd
2070                  *  instance for that interface. */
2071                 if (optind == argc - 1 && !(ctx.options & DHCPCD_MANAGER)) {
2072                         const char *per;
2073                         const char *ifname;
2074
2075                         ifname = *ctx.ifv;
2076                         if (ifname == NULL || strlen(ifname) > IF_NAMESIZE) {
2077                                 errno = ifname == NULL ? EINVAL : E2BIG;
2078                                 logerr("%s: ", ifname);
2079                                 goto exit_failure;
2080                         }
2081                         /* Allow a dhcpcd interface per address family */
2082                         switch(family) {
2083                         case AF_INET:
2084                                 per = "-4";
2085                                 break;
2086                         case AF_INET6:
2087                                 per = "-6";
2088                                 break;
2089                         default:
2090                                 per = "";
2091                         }
2092                         snprintf(ctx.pidfile, sizeof(ctx.pidfile),
2093                             PIDFILE, ifname, per, ".");
2094                 } else {
2095                         snprintf(ctx.pidfile, sizeof(ctx.pidfile),
2096                             PIDFILE, "", "", "");
2097                         ctx.options |= DHCPCD_MANAGER;
2098                 }
2099                 if (ctx.options & DHCPCD_PRINT_PIDFILE) {
2100                         printf("%s\n", ctx.pidfile);
2101                         goto exit_success;
2102                 }
2103         }
2104
2105         if (chdir("/") == -1)
2106                 logerr("%s: chdir: /", __func__);
2107
2108         /* Freeing allocated addresses from dumping leases can trigger
2109          * eloop removals as well, so init here. */
2110         if ((ctx.eloop = eloop_new()) == NULL) {
2111                 logerr("%s: eloop_init", __func__);
2112                 goto exit_failure;
2113         }
2114
2115 #ifdef USE_SIGNALS
2116         for (si = 0; si < dhcpcd_signals_ignore_len; si++)
2117                 signal(dhcpcd_signals_ignore[si], SIG_IGN);
2118
2119         /* Save signal mask, block and redirect signals to our handler */
2120         eloop_signal_set_cb(ctx.eloop,
2121             dhcpcd_signals, dhcpcd_signals_len,
2122             dhcpcd_signal_cb, &ctx);
2123         if (eloop_signal_mask(ctx.eloop, &ctx.sigset) == -1) {
2124                 logerr("%s: eloop_signal_mask", __func__);
2125                 goto exit_failure;
2126         }
2127
2128         if (sig != 0) {
2129                 pid = pidfile_read(ctx.pidfile);
2130                 if (pid != 0 && pid != -1)
2131                         loginfox("sending signal %s to pid %d", siga, pid);
2132                 if (pid == 0 || pid == -1 || kill(pid, sig) != 0) {
2133                         if (sig != SIGHUP && sig != SIGUSR1 && errno != EPERM)
2134                                 logerrx(PACKAGE" not running");
2135                         if (pid != 0 && pid != -1 && errno != ESRCH) {
2136                                 logerr("kill");
2137                                 goto exit_failure;
2138                         }
2139                         unlink(ctx.pidfile);
2140                         if (sig != SIGHUP && sig != SIGUSR1)
2141                                 goto exit_failure;
2142                 } else {
2143                         struct timespec ts;
2144
2145                         if (sig == SIGHUP || sig == SIGUSR1)
2146                                 goto exit_success;
2147                         /* Spin until it exits */
2148                         loginfox("waiting for pid %d to exit", pid);
2149                         ts.tv_sec = 0;
2150                         ts.tv_nsec = 100000000; /* 10th of a second */
2151                         for(i = 0; i < 100; i++) {
2152                                 nanosleep(&ts, NULL);
2153                                 if (pidfile_read(ctx.pidfile) == -1)
2154                                         goto exit_success;
2155                         }
2156                         logerrx("pid %d failed to exit", pid);
2157                         goto exit_failure;
2158                 }
2159         }
2160 #endif
2161
2162 #ifdef PRIVSEP
2163         ps_init(&ctx);
2164 #endif
2165
2166 #ifndef SMALL
2167         if (ctx.options & DHCPCD_DUMPLEASE &&
2168             ioctl(fileno(stdin), FIONREAD, &i, sizeof(i)) == 0 &&
2169             i > 0)
2170         {
2171                 ctx.options |= DHCPCD_FORKED; /* pretend child process */
2172 #ifdef PRIVSEP
2173                 if (IN_PRIVSEP(&ctx) && ps_managersandbox(&ctx, NULL) == -1)
2174                         goto exit_failure;
2175 #endif
2176                 ifp = calloc(1, sizeof(*ifp));
2177                 if (ifp == NULL) {
2178                         logerr(__func__);
2179                         goto exit_failure;
2180                 }
2181                 ifp->ctx = &ctx;
2182                 ifp->options = ifo;
2183                 switch (family) {
2184                 case AF_INET:
2185 #ifdef INET
2186                         if (dhcp_dump(ifp) == -1)
2187                                 goto exit_failure;
2188                         break;
2189 #else
2190                         logerrx("No DHCP support");
2191                         goto exit_failure;
2192 #endif
2193                 case AF_INET6:
2194 #ifdef DHCP6
2195                         if (dhcp6_dump(ifp) == -1)
2196                                 goto exit_failure;
2197                         break;
2198 #else
2199                         logerrx("No DHCP6 support");
2200                         goto exit_failure;
2201 #endif
2202                 default:
2203                         logerrx("Family not specified. Please use -4 or -6.");
2204                         goto exit_failure;
2205                 }
2206                 goto exit_success;
2207         }
2208 #endif
2209
2210         /* Test against siga instead of sig to avoid gcc
2211          * warning about a bogus potential signed overflow.
2212          * The end result will be the same. */
2213         if ((siga == NULL || i == 4 || ctx.ifc != 0) &&
2214             !(ctx.options & DHCPCD_TEST))
2215         {
2216                 ctx.options |= DHCPCD_FORKED; /* avoid socket unlink */
2217                 if (!(ctx.options & DHCPCD_MANAGER))
2218                         ctx.control_fd = control_open(argv[optind], family,
2219                             ctx.options & DHCPCD_DUMPLEASE);
2220                 if (!(ctx.options & DHCPCD_MANAGER) && ctx.control_fd == -1)
2221                         ctx.control_fd = control_open(argv[optind], AF_UNSPEC,
2222                             ctx.options & DHCPCD_DUMPLEASE);
2223                 if (ctx.control_fd == -1)
2224                         ctx.control_fd = control_open(NULL, AF_UNSPEC,
2225                             ctx.options & DHCPCD_DUMPLEASE);
2226                 if (ctx.control_fd != -1) {
2227 #ifdef PRIVSEP
2228                         if (IN_PRIVSEP(&ctx) &&
2229                             ps_managersandbox(&ctx, NULL) == -1)
2230                                 goto exit_failure;
2231 #endif
2232                         if (!(ctx.options & DHCPCD_DUMPLEASE))
2233                                 loginfox("sending commands to dhcpcd process");
2234                         len = control_send(&ctx, argc, argv);
2235                         if (len > 0)
2236                                 logdebugx("send OK");
2237                         else {
2238                                 logerr("%s: control_send", __func__);
2239                                 goto exit_failure;
2240                         }
2241                         if (ctx.options & DHCPCD_DUMPLEASE) {
2242                                 if (dhcpcd_readdump(&ctx) == -1) {
2243                                         logerr("%s: dhcpcd_readdump", __func__);
2244                                         goto exit_failure;
2245                                 }
2246                                 goto run_loop;
2247                         }
2248                         goto exit_success;
2249                 } else {
2250                         if (errno != ENOENT)
2251                                 logerr("%s: control_open", __func__);
2252                         if (ctx.options & DHCPCD_DUMPLEASE) {
2253                                 if (errno == ENOENT)
2254                                         logerrx("dhcpcd is not running");
2255                                 goto exit_failure;
2256                         }
2257                         if (errno == EPERM || errno == EACCES)
2258                                 goto exit_failure;
2259                 }
2260                 ctx.options &= ~DHCPCD_FORKED;
2261         }
2262
2263         if (!(ctx.options & DHCPCD_TEST)) {
2264                 /* Ensure we have the needed directories */
2265                 if (mkdir(DBDIR, 0750) == -1 && errno != EEXIST)
2266                         logerr("%s: mkdir: %s", __func__, DBDIR);
2267                 if (mkdir(RUNDIR, 0755) == -1 && errno != EEXIST)
2268                         logerr("%s: mkdir: %s", __func__, RUNDIR);
2269                 if ((pid = pidfile_lock(ctx.pidfile)) != 0) {
2270                         if (pid == -1)
2271                                 logerr("%s: pidfile_lock: %s",
2272                                     __func__, ctx.pidfile);
2273                         else
2274                                 logerrx(PACKAGE
2275                                     " already running on pid %d (%s)",
2276                                     pid, ctx.pidfile);
2277                         goto exit_failure;
2278                 }
2279         }
2280
2281         loginfox(PACKAGE "-" VERSION " starting");
2282         if (ctx.stdin_valid && freopen(_PATH_DEVNULL, "w", stdin) == NULL)
2283                 logwarn("freopen stdin");
2284
2285 #if defined(USE_SIGNALS) && !defined(THERE_IS_NO_FORK)
2286         if (!(ctx.options & DHCPCD_DAEMONISE))
2287                 goto start_manager;
2288
2289         if (xsocketpair(AF_UNIX, SOCK_DGRAM | SOCK_CXNB, 0, fork_fd) == -1 ||
2290             (ctx.stderr_valid &&
2291             xsocketpair(AF_UNIX, SOCK_DGRAM | SOCK_CXNB, 0, stderr_fd) == -1))
2292         {
2293                 logerr("socketpair");
2294                 goto exit_failure;
2295         }
2296         switch (pid = fork()) {
2297         case -1:
2298                 logerr("fork");
2299                 goto exit_failure;
2300         case 0:
2301                 ctx.fork_fd = fork_fd[1];
2302                 close(fork_fd[0]);
2303 #ifdef PRIVSEP_RIGHTS
2304                 if (ps_rights_limit_fd(ctx.fork_fd) == -1) {
2305                         logerr("ps_rights_limit_fdpair");
2306                         goto exit_failure;
2307                 }
2308 #endif
2309                 eloop_event_add(ctx.eloop, ctx.fork_fd, dhcpcd_fork_cb, &ctx);
2310
2311                 /*
2312                  * Redirect stderr to the stderr socketpair.
2313                  * Redirect stdout as well.
2314                  * dhcpcd doesn't output via stdout, but something in
2315                  * a called script might.
2316                  */
2317                 if (ctx.stderr_valid) {
2318                         if (dup2(stderr_fd[1], STDERR_FILENO) == -1 ||
2319                             (ctx.stdout_valid &&
2320                             dup2(stderr_fd[1], STDOUT_FILENO) == -1))
2321                                 logerr("dup2");
2322                         close(stderr_fd[0]);
2323                         close(stderr_fd[1]);
2324                 } else if (ctx.stdout_valid) {
2325                         if (freopen(_PATH_DEVNULL, "w", stdout) == NULL)
2326                                 logerr("freopen stdout");
2327                 }
2328                 if (setsid() == -1) {
2329                         logerr("%s: setsid", __func__);
2330                         goto exit_failure;
2331                 }
2332                 /* Ensure we can never get a controlling terminal */
2333                 switch (pid = fork()) {
2334                 case -1:
2335                         logerr("fork");
2336                         goto exit_failure;
2337                 case 0:
2338                         break;
2339                 default:
2340                         ctx.options |= DHCPCD_FORKED; /* A lie */
2341                         i = EXIT_SUCCESS;
2342                         goto exit1;
2343                 }
2344                 break;
2345         default:
2346                 setproctitle("[launcher]");
2347                 ctx.options |= DHCPCD_FORKED | DHCPCD_LAUNCHER;
2348                 ctx.fork_fd = fork_fd[0];
2349                 close(fork_fd[1]);
2350 #ifdef PRIVSEP_RIGHTS
2351                 if (ps_rights_limit_fd(ctx.fork_fd) == -1) {
2352                         logerr("ps_rights_limit_fd");
2353                         goto exit_failure;
2354                 }
2355 #endif
2356                 eloop_event_add(ctx.eloop, ctx.fork_fd, dhcpcd_fork_cb, &ctx);
2357
2358                 if (ctx.stderr_valid) {
2359                         ctx.stderr_fd = stderr_fd[0];
2360                         close(stderr_fd[1]);
2361 #ifdef PRIVSEP_RIGHTS
2362                         if (ps_rights_limit_fd(ctx.stderr_fd) == 1) {
2363                                 logerr("ps_rights_limit_fd");
2364                                 goto exit_failure;
2365                         }
2366 #endif
2367                         eloop_event_add(ctx.eloop, ctx.stderr_fd,
2368                             dhcpcd_stderr_cb, &ctx);
2369                 }
2370 #ifdef PRIVSEP
2371                 if (IN_PRIVSEP(&ctx) && ps_managersandbox(&ctx, NULL) == -1)
2372                         goto exit_failure;
2373 #endif
2374                 goto run_loop;
2375         }
2376
2377         /* We have now forked, setsid, forked once more.
2378          * From this point on, we are the controlling daemon. */
2379         logdebugx("spawned manager process on PID %d", getpid());
2380 start_manager:
2381         ctx.options |= DHCPCD_STARTED;
2382         if ((pid = pidfile_lock(ctx.pidfile)) != 0) {
2383                 logerr("%s: pidfile_lock %d", __func__, pid);
2384 #ifdef PRIVSEP
2385                 /* privsep has not started ... */
2386                 ctx.options &= ~DHCPCD_PRIVSEP;
2387 #endif
2388                 goto exit_failure;
2389         }
2390 #endif
2391
2392         os_init();
2393
2394 #if defined(BSD) && defined(INET6)
2395         /* Disable the kernel RTADV sysctl as early as possible. */
2396         if (ctx.options & DHCPCD_IPV6 && ctx.options & DHCPCD_IPV6RS)
2397                 if_disable_rtadv();
2398 #endif
2399
2400 #ifdef PRIVSEP
2401         if (IN_PRIVSEP(&ctx) && ps_start(&ctx) == -1) {
2402                 logerr("ps_start");
2403                 goto exit_failure;
2404         }
2405         if (ctx.options & DHCPCD_FORKED)
2406                 goto run_loop;
2407 #endif
2408
2409         if (!(ctx.options & DHCPCD_TEST)) {
2410                 if (control_start(&ctx,
2411                     ctx.options & DHCPCD_MANAGER ?
2412                     NULL : argv[optind], family) == -1)
2413                 {
2414                         logerr("%s: control_start", __func__);
2415                         goto exit_failure;
2416                 }
2417         }
2418
2419 #ifdef PLUGIN_DEV
2420         /* Start any dev listening plugin which may want to
2421          * change the interface name provided by the kernel */
2422         if (!IN_PRIVSEP(&ctx) &&
2423             (ctx.options & (DHCPCD_MANAGER | DHCPCD_DEV)) ==
2424             (DHCPCD_MANAGER | DHCPCD_DEV))
2425                 dev_start(&ctx, dhcpcd_handleinterface);
2426 #endif
2427
2428         setproctitle("%s%s%s",
2429             ctx.options & DHCPCD_MANAGER ? "[manager]" : argv[optind],
2430             ctx.options & DHCPCD_IPV4 ? " [ip4]" : "",
2431             ctx.options & DHCPCD_IPV6 ? " [ip6]" : "");
2432
2433         if (if_opensockets(&ctx) == -1) {
2434                 logerr("%s: if_opensockets", __func__);
2435                 goto exit_failure;
2436         }
2437 #ifndef SMALL
2438         dhcpcd_setlinkrcvbuf(&ctx);
2439 #endif
2440
2441         /* Try and create DUID from the machine UUID. */
2442         dhcpcd_initduid(&ctx, NULL);
2443
2444         /* Cache the default vendor option. */
2445         if (dhcp_vendor(ctx.vendor, sizeof(ctx.vendor)) == -1)
2446                 logerr("dhcp_vendor");
2447
2448         /* Start handling kernel messages for interfaces, addresses and
2449          * routes. */
2450         eloop_event_add(ctx.eloop, ctx.link_fd, dhcpcd_handlelink, &ctx);
2451
2452 #ifdef PRIVSEP
2453         if (IN_PRIVSEP(&ctx) && ps_managersandbox(&ctx, "stdio route") == -1)
2454                 goto exit_failure;
2455 #endif
2456
2457         /* When running dhcpcd against a single interface, we need to retain
2458          * the old behaviour of waiting for an IP address */
2459         if (ctx.ifc == 1 && !(ctx.options & DHCPCD_BACKGROUND))
2460                 ctx.options |= DHCPCD_WAITIP;
2461
2462         ctx.ifaces = if_discover(&ctx, &ifaddrs, ctx.ifc, ctx.ifv);
2463         if (ctx.ifaces == NULL) {
2464                 logerr("%s: if_discover", __func__);
2465                 goto exit_failure;
2466         }
2467         for (i = 0; i < ctx.ifc; i++) {
2468                 if ((ifp = if_find(ctx.ifaces, ctx.ifv[i])) == NULL)
2469                         logerrx("%s: interface not found",
2470                             ctx.ifv[i]);
2471                 else if (!ifp->active)
2472                         logerrx("%s: interface has an invalid configuration",
2473                             ctx.ifv[i]);
2474         }
2475         TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2476                 if (ifp->active == IF_ACTIVE_USER)
2477                         break;
2478         }
2479         if (ifp == NULL) {
2480                 if (ctx.ifc == 0) {
2481                         int loglevel;
2482
2483                         loglevel = ctx.options & DHCPCD_INACTIVE ?
2484                             LOG_DEBUG : LOG_ERR;
2485                         logmessage(loglevel, "no valid interfaces found");
2486                         dhcpcd_daemonise(&ctx);
2487                 } else
2488                         goto exit_failure;
2489                 if (!(ctx.options & DHCPCD_LINK)) {
2490                         logerrx("aborting as link detection is disabled");
2491                         goto exit_failure;
2492                 }
2493         }
2494
2495         TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2496                 if (ifp->active)
2497                         dhcpcd_initstate1(ifp, argc, argv, 0);
2498         }
2499         if_learnaddrs(&ctx, ctx.ifaces, &ifaddrs);
2500
2501         if (ctx.options & DHCPCD_BACKGROUND)
2502                 dhcpcd_daemonise(&ctx);
2503
2504         opt = 0;
2505         TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2506                 if (ifp->active) {
2507                         run_preinit(ifp);
2508                         if (if_is_link_up(ifp))
2509                                 opt = 1;
2510                 }
2511         }
2512
2513         if (!(ctx.options & DHCPCD_BACKGROUND)) {
2514                 if (ctx.options & DHCPCD_MANAGER)
2515                         t = ifo->timeout;
2516                 else {
2517                         t = 0;
2518                         TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2519                                 if (ifp->active) {
2520                                         t = ifp->options->timeout;
2521                                         break;
2522                                 }
2523                         }
2524                 }
2525                 if (opt == 0 &&
2526                     ctx.options & DHCPCD_LINK &&
2527                     !(ctx.options & DHCPCD_WAITIP))
2528                 {
2529                         int loglevel;
2530
2531                         loglevel = ctx.options & DHCPCD_INACTIVE ?
2532                             LOG_DEBUG : LOG_WARNING;
2533                         logmessage(loglevel, "no interfaces have a carrier");
2534                         dhcpcd_daemonise(&ctx);
2535                 } else if (t > 0 &&
2536                     /* Test mode removes the daemonise bit, so check for both */
2537                     ctx.options & (DHCPCD_DAEMONISE | DHCPCD_TEST))
2538                 {
2539                         eloop_timeout_add_sec(ctx.eloop, t,
2540                             handle_exit_timeout, &ctx);
2541                 }
2542         }
2543         free_options(&ctx, ifo);
2544         ifo = NULL;
2545
2546         TAILQ_FOREACH(ifp, ctx.ifaces, next) {
2547                 if (ifp->active)
2548                         eloop_timeout_add_sec(ctx.eloop, 0,
2549                             dhcpcd_prestartinterface, ifp);
2550         }
2551
2552 run_loop:
2553         i = eloop_start(ctx.eloop, &ctx.sigset);
2554         if (i < 0) {
2555                 logerr("%s: eloop_start", __func__);
2556                 goto exit_failure;
2557         }
2558         goto exit1;
2559
2560 exit_success:
2561         i = EXIT_SUCCESS;
2562         goto exit1;
2563
2564 exit_failure:
2565         i = EXIT_FAILURE;
2566
2567 exit1:
2568         if (!(ctx.options & DHCPCD_TEST) && control_stop(&ctx) == -1)
2569                 logerr("%s: control_stop", __func__);
2570         if (ifaddrs != NULL) {
2571 #ifdef PRIVSEP_GETIFADDRS
2572                 if (IN_PRIVSEP(&ctx))
2573                         free(ifaddrs);
2574                 else
2575 #endif
2576                         freeifaddrs(ifaddrs);
2577         }
2578         /* ps_stop will clear DHCPCD_PRIVSEP but we need to
2579          * remember it to avoid attemping to remove the pidfile */
2580         oi = ctx.options & DHCPCD_PRIVSEP ? 1 : 0;
2581 #ifdef PRIVSEP
2582         ps_stop(&ctx);
2583 #endif
2584         /* Free memory and close fd's */
2585         if (ctx.ifaces) {
2586                 while ((ifp = TAILQ_FIRST(ctx.ifaces))) {
2587                         TAILQ_REMOVE(ctx.ifaces, ifp, next);
2588                         if_free(ifp);
2589                 }
2590                 free(ctx.ifaces);
2591                 ctx.ifaces = NULL;
2592         }
2593         free_options(&ctx, ifo);
2594 #ifdef HAVE_OPEN_MEMSTREAM
2595         if (ctx.script_fp)
2596                 fclose(ctx.script_fp);
2597 #endif
2598         free(ctx.script_buf);
2599         free(ctx.script_env);
2600         rt_dispose(&ctx);
2601         free(ctx.duid);
2602         if (ctx.link_fd != -1) {
2603                 eloop_event_delete(ctx.eloop, ctx.link_fd);
2604                 close(ctx.link_fd);
2605         }
2606         if_closesockets(&ctx);
2607         free_globals(&ctx);
2608 #ifdef INET6
2609         ipv6_ctxfree(&ctx);
2610 #endif
2611 #ifdef PLUGIN_DEV
2612         dev_stop(&ctx);
2613 #endif
2614 #ifdef PRIVSEP
2615         eloop_free(ctx.ps_eloop);
2616 #endif
2617         eloop_free(ctx.eloop);
2618         if (ctx.script != dhcpcd_default_script)
2619                 free(ctx.script);
2620         if (ctx.options & DHCPCD_STARTED && !(ctx.options & DHCPCD_FORKED))
2621                 loginfox(PACKAGE " exited");
2622         logclose();
2623         free(ctx.logfile);
2624         free(ctx.ctl_buf);
2625 #ifdef SETPROCTITLE_H
2626         setproctitle_fini();
2627 #endif
2628 #ifdef USE_SIGNALS
2629         if (ctx.options & DHCPCD_STARTED) {
2630                 /* Try to detach from the launch process. */
2631                 if (ctx.fork_fd != -1 &&
2632                     write(ctx.fork_fd, &i, sizeof(i)) == -1)
2633                         logerr("%s: write", __func__);
2634         }
2635         if (ctx.options & DHCPCD_FORKED || oi != 0)
2636                 _exit(i); /* so atexit won't remove our pidfile */
2637 #endif
2638         return i;
2639 }