xref: /freebsd/contrib/unbound/daemon/unbound.c (revision 78adacd4eab39a3508bd8c65f0aba94fc6b907ce)
1 /*
2  * daemon/unbound.c - main program for unbound DNS resolver daemon.
3  *
4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  *
35  */
36 
37 /**
38  * \file
39  *
40  * Main program to start the DNS resolver daemon.
41  */
42 
43 #include "config.h"
44 #ifdef HAVE_GETOPT_H
45 #include <getopt.h>
46 #endif
47 #include <sys/time.h>
48 #include "util/log.h"
49 #include "daemon/daemon.h"
50 #include "daemon/remote.h"
51 #include "util/config_file.h"
52 #include "util/storage/slabhash.h"
53 #include "services/listen_dnsport.h"
54 #include "services/cache/rrset.h"
55 #include "services/cache/infra.h"
56 #include "util/fptr_wlist.h"
57 #include "util/data/msgreply.h"
58 #include "util/module.h"
59 #include "util/net_help.h"
60 #include "util/ub_event.h"
61 #include <signal.h>
62 #include <fcntl.h>
63 #include <openssl/crypto.h>
64 #ifdef HAVE_PWD_H
65 #include <pwd.h>
66 #endif
67 #ifdef HAVE_GRP_H
68 #include <grp.h>
69 #endif
70 #include <openssl/ssl.h>
71 
72 #ifndef S_SPLINT_S
73 /* splint chokes on this system header file */
74 #ifdef HAVE_SYS_RESOURCE_H
75 #include <sys/resource.h>
76 #endif
77 #endif /* S_SPLINT_S */
78 #ifdef HAVE_LOGIN_CAP_H
79 #include <login_cap.h>
80 #endif
81 
82 #ifdef UB_ON_WINDOWS
83 #  include "winrc/win_svc.h"
84 #endif
85 
86 #ifdef HAVE_NSS
87 /* nss3 */
88 #  include "nss.h"
89 #endif
90 
91 #ifdef HAVE_TARGETCONDITIONALS_H
92 #include <TargetConditionals.h>
93 #endif
94 
95 #if (defined(TARGET_OS_TV) && TARGET_OS_TV) || (defined(TARGET_OS_WATCH) && TARGET_OS_WATCH)
96 #undef HAVE_FORK
97 #endif
98 
99 /** print build options. */
100 static void
101 print_build_options(void)
102 {
103 	const char** m;
104 	const char *evnm="event", *evsys="", *evmethod="";
105 	time_t t;
106 	struct timeval now;
107 	struct ub_event_base* base;
108 	printf("Version %s\n\n", PACKAGE_VERSION);
109 	printf("Configure line: %s\n", CONFCMDLINE);
110 	base = ub_default_event_base(0,&t,&now);
111 	ub_get_event_sys(base, &evnm, &evsys, &evmethod);
112 	printf("Linked libs: %s %s (it uses %s), %s\n",
113 		evnm, evsys, evmethod,
114 #ifdef HAVE_SSL
115 #  ifdef SSLEAY_VERSION
116 		SSLeay_version(SSLEAY_VERSION)
117 #  else
118 		OpenSSL_version(OPENSSL_VERSION)
119 #  endif
120 #elif defined(HAVE_NSS)
121 		NSS_GetVersion()
122 #elif defined(HAVE_NETTLE)
123 		"nettle"
124 #endif
125 		);
126 	printf("Linked modules:");
127 	for(m = module_list_avail(); *m; m++)
128 		printf(" %s", *m);
129 	printf("\n");
130 #ifdef USE_DNSCRYPT
131 	printf("DNSCrypt feature available\n");
132 #endif
133 #ifdef USE_TCP_FASTOPEN
134 	printf("TCP Fastopen feature available\n");
135 #endif
136 	ub_event_base_free(base);
137 	printf("\nBSD licensed, see LICENSE in source package for details.\n");
138 	printf("Report bugs to %s\n", PACKAGE_BUGREPORT);
139 }
140 
141 /** print usage. */
142 static void
143 usage(void)
144 {
145 	printf("usage:  unbound [options]\n");
146 	printf("	start unbound daemon DNS resolver.\n");
147 	printf("-h	this help.\n");
148 	printf("-c file	config file to read instead of %s\n", CONFIGFILE);
149 	printf("	file format is described in unbound.conf(5).\n");
150 	printf("-d	do not fork into the background.\n");
151 	printf("-p	do not create a pidfile.\n");
152 	printf("-v	verbose (more times to increase verbosity).\n");
153 	printf("-V	show version number and build options.\n");
154 #ifdef UB_ON_WINDOWS
155 	printf("-w opt	windows option: \n");
156 	printf("   	install, remove - manage the services entry\n");
157 	printf("   	service - used to start from services control panel\n");
158 #endif
159 	printf("\nVersion %s\n", PACKAGE_VERSION);
160 	printf("BSD licensed, see LICENSE in source package for details.\n");
161 	printf("Report bugs to %s\n", PACKAGE_BUGREPORT);
162 }
163 
164 #ifndef unbound_testbound
165 int replay_var_compare(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
166 {
167         log_assert(0);
168         return 0;
169 }
170 #endif
171 
172 /** check file descriptor count */
173 static void
174 checkrlimits(struct config_file* cfg)
175 {
176 #ifndef S_SPLINT_S
177 #ifdef HAVE_GETRLIMIT
178 	/* list has number of ports to listen to, ifs number addresses */
179 	int list = ((cfg->do_udp?1:0) + (cfg->do_tcp?1 +
180 			(int)cfg->incoming_num_tcp:0));
181 	size_t listen_ifs = (size_t)(cfg->num_ifs==0?
182 		((cfg->do_ip4 && !cfg->if_automatic?1:0) +
183 		 (cfg->do_ip6?1:0)):cfg->num_ifs);
184 	size_t listen_num = list*listen_ifs;
185 	size_t outudpnum = (size_t)cfg->outgoing_num_ports;
186 	size_t outtcpnum = cfg->outgoing_num_tcp;
187 	size_t misc = 4; /* logfile, pidfile, stdout... */
188 	size_t perthread_noudp = listen_num + outtcpnum +
189 		2/*cmdpipe*/ + 2/*libevent*/ + misc;
190 	size_t perthread = perthread_noudp + outudpnum;
191 
192 #if !defined(HAVE_PTHREAD) && !defined(HAVE_SOLARIS_THREADS)
193 	int numthread = 1; /* it forks */
194 #else
195 	int numthread = (cfg->num_threads?cfg->num_threads:1);
196 #endif
197 	size_t total = numthread * perthread + misc;
198 	size_t avail;
199 	struct rlimit rlim;
200 
201 	if(total > 1024 &&
202 		strncmp(ub_event_get_version(), "mini-event", 10) == 0) {
203 		log_warn("too many file descriptors requested. The builtin"
204 			"mini-event cannot handle more than 1024. Config "
205 			"for less fds or compile with libevent");
206 		if(numthread*perthread_noudp+15 > 1024)
207 			fatal_exit("too much tcp. not enough fds.");
208 		cfg->outgoing_num_ports = (int)((1024
209 			- numthread*perthread_noudp
210 			- 10 /* safety margin */) /numthread);
211 		log_warn("continuing with less udp ports: %u",
212 			cfg->outgoing_num_ports);
213 		total = 1024;
214 	}
215 	if(perthread > 64 &&
216 		strncmp(ub_event_get_version(), "winsock-event", 13) == 0) {
217 		log_err("too many file descriptors requested. The winsock"
218 			" event handler cannot handle more than 64 per "
219 			" thread. Config for less fds");
220 		if(perthread_noudp+2 > 64)
221 			fatal_exit("too much tcp. not enough fds.");
222 		cfg->outgoing_num_ports = (int)((64
223 			- perthread_noudp
224 			- 2/* safety margin */));
225 		log_warn("continuing with less udp ports: %u",
226 			cfg->outgoing_num_ports);
227 		total = numthread*(perthread_noudp+
228 			(size_t)cfg->outgoing_num_ports)+misc;
229 	}
230 	if(getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
231 		log_warn("getrlimit: %s", strerror(errno));
232 		return;
233 	}
234 	if(rlim.rlim_cur == (rlim_t)RLIM_INFINITY)
235 		return;
236 	if((size_t)rlim.rlim_cur < total) {
237 		avail = (size_t)rlim.rlim_cur;
238 		rlim.rlim_cur = (rlim_t)(total + 10);
239 		rlim.rlim_max = (rlim_t)(total + 10);
240 #ifdef HAVE_SETRLIMIT
241 		if(setrlimit(RLIMIT_NOFILE, &rlim) < 0) {
242 			log_warn("setrlimit: %s", strerror(errno));
243 #endif
244 			log_warn("cannot increase max open fds from %u to %u",
245 				(unsigned)avail, (unsigned)total+10);
246 			/* check that calculation below does not underflow,
247 			 * with 15 as margin */
248 			if(numthread*perthread_noudp+15 > avail)
249 				fatal_exit("too much tcp. not enough fds.");
250 			cfg->outgoing_num_ports = (int)((avail
251 				- numthread*perthread_noudp
252 				- 10 /* safety margin */) /numthread);
253 			log_warn("continuing with less udp ports: %u",
254 				cfg->outgoing_num_ports);
255 			log_warn("increase ulimit or decrease threads, "
256 				"ports in config to remove this warning");
257 			return;
258 #ifdef HAVE_SETRLIMIT
259 		}
260 #endif
261 		verbose(VERB_ALGO, "increased limit(open files) from %u to %u",
262 			(unsigned)avail, (unsigned)total+10);
263 	}
264 #else
265 	(void)cfg;
266 #endif /* HAVE_GETRLIMIT */
267 #endif /* S_SPLINT_S */
268 }
269 
270 /** set verbosity, check rlimits, cache settings */
271 static void
272 apply_settings(struct daemon* daemon, struct config_file* cfg,
273 	int cmdline_verbose, int debug_mode)
274 {
275 	/* apply if they have changed */
276 	verbosity = cmdline_verbose + cfg->verbosity;
277 	if (debug_mode > 1) {
278 		cfg->use_syslog = 0;
279 		free(cfg->logfile);
280 		cfg->logfile = NULL;
281 	}
282 	daemon_apply_cfg(daemon, cfg);
283 	checkrlimits(cfg);
284 
285 	if (cfg->use_systemd && cfg->do_daemonize) {
286 		log_warn("use-systemd and do-daemonize should not be enabled at the same time");
287 	}
288 
289 	log_ident_set_or_default(cfg->log_identity);
290 }
291 
292 #ifdef HAVE_KILL
293 /** Read existing pid from pidfile.
294  * @param file: file name of pid file.
295  * @return: the pid from the file or -1 if none.
296  */
297 static pid_t
298 readpid (const char* file)
299 {
300 	int fd;
301 	pid_t pid;
302 	char pidbuf[32];
303 	char* t;
304 	ssize_t l;
305 
306 	if ((fd = open(file, O_RDONLY)) == -1) {
307 		if(errno != ENOENT)
308 			log_err("Could not read pidfile %s: %s",
309 				file, strerror(errno));
310 		return -1;
311 	}
312 
313 	if (((l = read(fd, pidbuf, sizeof(pidbuf)))) == -1) {
314 		if(errno != ENOENT)
315 			log_err("Could not read pidfile %s: %s",
316 				file, strerror(errno));
317 		close(fd);
318 		return -1;
319 	}
320 
321 	close(fd);
322 
323 	/* Empty pidfile means no pidfile... */
324 	if (l == 0) {
325 		return -1;
326 	}
327 
328 	pidbuf[sizeof(pidbuf)-1] = 0;
329 	pid = (pid_t)strtol(pidbuf, &t, 10);
330 
331 	if (*t && *t != '\n') {
332 		return -1;
333 	}
334 	return pid;
335 }
336 
337 /** write pid to file.
338  * @param pidfile: file name of pid file.
339  * @param pid: pid to write to file.
340  * @return false on failure
341  */
342 static int
343 writepid (const char* pidfile, pid_t pid)
344 {
345 	int fd;
346 	char pidbuf[32];
347 	size_t count = 0;
348 	snprintf(pidbuf, sizeof(pidbuf), "%lu\n", (unsigned long)pid);
349 
350 	if((fd = open(pidfile, O_WRONLY | O_CREAT | O_TRUNC
351 #ifdef O_NOFOLLOW
352 		| O_NOFOLLOW
353 #endif
354 		, 0644)) == -1) {
355 		log_err("cannot open pidfile %s: %s",
356 			pidfile, strerror(errno));
357 		return 0;
358 	}
359 	while(count < strlen(pidbuf)) {
360 		ssize_t r = write(fd, pidbuf+count, strlen(pidbuf)-count);
361 		if(r == -1) {
362 			if(errno == EAGAIN || errno == EINTR)
363 				continue;
364 			log_err("cannot write to pidfile %s: %s",
365 				pidfile, strerror(errno));
366 			close(fd);
367 			return 0;
368 		} else if(r == 0) {
369 			log_err("cannot write any bytes to pidfile %s: "
370 				"write returns 0 bytes written", pidfile);
371 			close(fd);
372 			return 0;
373 		}
374 		count += r;
375 	}
376 	close(fd);
377 	return 1;
378 }
379 
380 /**
381  * check old pid file.
382  * @param pidfile: the file name of the pid file.
383  * @param inchroot: if pidfile is inchroot and we can thus expect to
384  *	be able to delete it.
385  */
386 static void
387 checkoldpid(char* pidfile, int inchroot)
388 {
389 	pid_t old;
390 	if((old = readpid(pidfile)) != -1) {
391 		/* see if it is still alive */
392 		if(kill(old, 0) == 0 || errno == EPERM)
393 			log_warn("unbound is already running as pid %u.",
394 				(unsigned)old);
395 		else	if(inchroot)
396 			log_warn("did not exit gracefully last time (%u)",
397 				(unsigned)old);
398 	}
399 }
400 #endif /* HAVE_KILL */
401 
402 /** detach from command line */
403 static void
404 detach(void)
405 {
406 #if defined(HAVE_DAEMON) && !defined(DEPRECATED_DAEMON)
407 	/* use POSIX daemon(3) function */
408 	if(daemon(1, 0) != 0)
409 		fatal_exit("daemon failed: %s", strerror(errno));
410 #else /* no HAVE_DAEMON */
411 #ifdef HAVE_FORK
412 	int fd;
413 	/* Take off... */
414 	switch (fork()) {
415 		case 0:
416 			break;
417 		case -1:
418 			fatal_exit("fork failed: %s", strerror(errno));
419 		default:
420 			/* exit interactive session */
421 			exit(0);
422 	}
423 	/* detach */
424 #ifdef HAVE_SETSID
425 	if(setsid() == -1)
426 		fatal_exit("setsid() failed: %s", strerror(errno));
427 #endif
428 	if ((fd = open("/dev/null", O_RDWR, 0)) != -1) {
429 		(void)dup2(fd, STDIN_FILENO);
430 		(void)dup2(fd, STDOUT_FILENO);
431 		(void)dup2(fd, STDERR_FILENO);
432 		if (fd > 2)
433 			(void)close(fd);
434 	}
435 #endif /* HAVE_FORK */
436 #endif /* HAVE_DAEMON */
437 }
438 
439 /** daemonize, drop user privileges and chroot if needed */
440 static void
441 perform_setup(struct daemon* daemon, struct config_file* cfg, int debug_mode,
442 	const char** cfgfile, int need_pidfile)
443 {
444 #ifdef HAVE_KILL
445 	int pidinchroot;
446 #endif
447 #ifdef HAVE_GETPWNAM
448 	struct passwd *pwd = NULL;
449 
450 	if(cfg->username && cfg->username[0]) {
451 		if((pwd = getpwnam(cfg->username)) == NULL)
452 			fatal_exit("user '%s' does not exist.", cfg->username);
453 		/* endpwent below, in case we need pwd for setusercontext */
454 	}
455 #endif
456 #ifdef UB_ON_WINDOWS
457 	w_config_adjust_directory(cfg);
458 #endif
459 
460 	/* read ssl keys while superuser and outside chroot */
461 #ifdef HAVE_SSL
462 	if(!(daemon->rc = daemon_remote_create(cfg)))
463 		fatal_exit("could not set up remote-control");
464 	if(cfg->ssl_service_key && cfg->ssl_service_key[0]) {
465 		if(!(daemon->listen_sslctx = listen_sslctx_create(
466 			cfg->ssl_service_key, cfg->ssl_service_pem, NULL)))
467 			fatal_exit("could not set up listen SSL_CTX");
468 		if(cfg->tls_ciphers && cfg->tls_ciphers[0]) {
469 			if (!SSL_CTX_set_cipher_list(daemon->listen_sslctx, cfg->tls_ciphers)) {
470 				fatal_exit("failed to set tls-cipher %s", cfg->tls_ciphers);
471 			}
472 		}
473 #ifdef HAVE_SSL_CTX_SET_CIPHERSUITES
474 		if(cfg->tls_ciphersuites && cfg->tls_ciphersuites[0]) {
475 			if (!SSL_CTX_set_ciphersuites(daemon->listen_sslctx, cfg->tls_ciphersuites)) {
476 				fatal_exit("failed to set tls-ciphersuites %s", cfg->tls_ciphersuites);
477 			}
478 		}
479 #endif
480 		if(cfg->tls_session_ticket_keys.first &&
481 			cfg->tls_session_ticket_keys.first->str[0] != 0) {
482 			if(!listen_sslctx_setup_ticket_keys(daemon->listen_sslctx, cfg->tls_session_ticket_keys.first)) {
483 				fatal_exit("could not set session ticket SSL_CTX");
484 			}
485 		}
486 	}
487 	if(!(daemon->connect_sslctx = connect_sslctx_create(NULL, NULL,
488 		cfg->tls_cert_bundle, cfg->tls_win_cert)))
489 		fatal_exit("could not set up connect SSL_CTX");
490 #endif
491 
492 	/* init syslog (as root) if needed, before daemonize, otherwise
493 	 * a fork error could not be printed since daemonize closed stderr.*/
494 	if(cfg->use_syslog) {
495 		log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir);
496 	}
497 	/* if using a logfile, we cannot open it because the logfile would
498 	 * be created with the wrong permissions, we cannot chown it because
499 	 * we cannot chown system logfiles, so we do not open at all.
500 	 * So, using a logfile, the user does not see errors unless -d is
501 	 * given to unbound on the commandline. */
502 
503 #ifdef HAVE_KILL
504 	/* true if pidfile is inside chrootdir, or nochroot */
505 	pidinchroot = need_pidfile && (!(cfg->chrootdir && cfg->chrootdir[0]) ||
506 				(cfg->chrootdir && cfg->chrootdir[0] &&
507 				strncmp(cfg->pidfile, cfg->chrootdir,
508 				strlen(cfg->chrootdir))==0));
509 
510 	/* check old pid file before forking */
511 	if(cfg->pidfile && cfg->pidfile[0] && need_pidfile) {
512 		/* calculate position of pidfile */
513 		if(cfg->pidfile[0] == '/')
514 			daemon->pidfile = strdup(cfg->pidfile);
515 		else	daemon->pidfile = fname_after_chroot(cfg->pidfile,
516 				cfg, 1);
517 		if(!daemon->pidfile)
518 			fatal_exit("pidfile alloc: out of memory");
519 		checkoldpid(daemon->pidfile, pidinchroot);
520 	}
521 #endif
522 
523 	/* daemonize because pid is needed by the writepid func */
524 	if(!debug_mode && cfg->do_daemonize) {
525 		detach();
526 	}
527 
528 	/* write new pidfile (while still root, so can be outside chroot) */
529 #ifdef HAVE_KILL
530 	if(cfg->pidfile && cfg->pidfile[0] && need_pidfile) {
531 		if(writepid(daemon->pidfile, getpid())) {
532 			if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1 &&
533 				pidinchroot) {
534 #  ifdef HAVE_CHOWN
535 				if(chown(daemon->pidfile, cfg_uid, cfg_gid) == -1) {
536 					verbose(VERB_QUERY, "cannot chown %u.%u %s: %s",
537 						(unsigned)cfg_uid, (unsigned)cfg_gid,
538 						daemon->pidfile, strerror(errno));
539 				}
540 #  endif /* HAVE_CHOWN */
541 			}
542 		}
543 	}
544 #else
545 	(void)daemon;
546 	(void)need_pidfile;
547 #endif /* HAVE_KILL */
548 
549 	/* Set user context */
550 #ifdef HAVE_GETPWNAM
551 	if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) {
552 #ifdef HAVE_SETUSERCONTEXT
553 		/* setusercontext does initgroups, setuid, setgid, and
554 		 * also resource limits from login config, but we
555 		 * still call setresuid, setresgid to be sure to set all uid*/
556 		if(setusercontext(NULL, pwd, cfg_uid, (unsigned)
557 			LOGIN_SETALL & ~LOGIN_SETUSER & ~LOGIN_SETGROUP) != 0)
558 			log_warn("unable to setusercontext %s: %s",
559 				cfg->username, strerror(errno));
560 #else
561 		(void)pwd;
562 #endif /* HAVE_SETUSERCONTEXT */
563 	}
564 #endif /* HAVE_GETPWNAM */
565 
566 	/* box into the chroot */
567 #ifdef HAVE_CHROOT
568 	if(cfg->chrootdir && cfg->chrootdir[0]) {
569 		if(chdir(cfg->chrootdir)) {
570 			fatal_exit("unable to chdir to chroot %s: %s",
571 				cfg->chrootdir, strerror(errno));
572 		}
573 		verbose(VERB_QUERY, "chdir to %s", cfg->chrootdir);
574 		if(chroot(cfg->chrootdir))
575 			fatal_exit("unable to chroot to %s: %s",
576 				cfg->chrootdir, strerror(errno));
577 		if(chdir("/"))
578 			fatal_exit("unable to chdir to / in chroot %s: %s",
579 				cfg->chrootdir, strerror(errno));
580 		verbose(VERB_QUERY, "chroot to %s", cfg->chrootdir);
581 		if(strncmp(*cfgfile, cfg->chrootdir,
582 			strlen(cfg->chrootdir)) == 0)
583 			(*cfgfile) += strlen(cfg->chrootdir);
584 
585 		/* adjust stored pidfile for chroot */
586 		if(daemon->pidfile && daemon->pidfile[0] &&
587 			strncmp(daemon->pidfile, cfg->chrootdir,
588 			strlen(cfg->chrootdir))==0) {
589 			char* old = daemon->pidfile;
590 			daemon->pidfile = strdup(old+strlen(cfg->chrootdir));
591 			free(old);
592 			if(!daemon->pidfile)
593 				log_err("out of memory in pidfile adjust");
594 		}
595 		daemon->chroot = strdup(cfg->chrootdir);
596 		if(!daemon->chroot)
597 			log_err("out of memory in daemon chroot dir storage");
598 	}
599 #else
600 	(void)cfgfile;
601 #endif
602 	/* change to working directory inside chroot */
603 	if(cfg->directory && cfg->directory[0]) {
604 		char* dir = cfg->directory;
605 		if(cfg->chrootdir && cfg->chrootdir[0] &&
606 			strncmp(dir, cfg->chrootdir,
607 			strlen(cfg->chrootdir)) == 0)
608 			dir += strlen(cfg->chrootdir);
609 		if(dir[0]) {
610 			if(chdir(dir)) {
611 				fatal_exit("Could not chdir to %s: %s",
612 					dir, strerror(errno));
613 			}
614 			verbose(VERB_QUERY, "chdir to %s", dir);
615 		}
616 	}
617 
618 	/* drop permissions after chroot, getpwnam, pidfile, syslog done*/
619 #ifdef HAVE_GETPWNAM
620 	if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) {
621 #  ifdef HAVE_INITGROUPS
622 		if(initgroups(cfg->username, cfg_gid) != 0)
623 			log_warn("unable to initgroups %s: %s",
624 				cfg->username, strerror(errno));
625 #  endif /* HAVE_INITGROUPS */
626 #  ifdef HAVE_ENDPWENT
627 		endpwent();
628 #  endif
629 
630 #ifdef HAVE_SETRESGID
631 		if(setresgid(cfg_gid,cfg_gid,cfg_gid) != 0)
632 #elif defined(HAVE_SETREGID) && !defined(DARWIN_BROKEN_SETREUID)
633 		if(setregid(cfg_gid,cfg_gid) != 0)
634 #else /* use setgid */
635 		if(setgid(cfg_gid) != 0)
636 #endif /* HAVE_SETRESGID */
637 			fatal_exit("unable to set group id of %s: %s",
638 				cfg->username, strerror(errno));
639 #ifdef HAVE_SETRESUID
640 		if(setresuid(cfg_uid,cfg_uid,cfg_uid) != 0)
641 #elif defined(HAVE_SETREUID) && !defined(DARWIN_BROKEN_SETREUID)
642 		if(setreuid(cfg_uid,cfg_uid) != 0)
643 #else /* use setuid */
644 		if(setuid(cfg_uid) != 0)
645 #endif /* HAVE_SETRESUID */
646 			fatal_exit("unable to set user id of %s: %s",
647 				cfg->username, strerror(errno));
648 		verbose(VERB_QUERY, "drop user privileges, run as %s",
649 			cfg->username);
650 	}
651 #endif /* HAVE_GETPWNAM */
652 	/* file logging inited after chroot,chdir,setuid is done so that
653 	 * it would succeed on SIGHUP as well */
654 	if(!cfg->use_syslog)
655 		log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir);
656 }
657 
658 /**
659  * Run the daemon.
660  * @param cfgfile: the config file name.
661  * @param cmdline_verbose: verbosity resulting from commandline -v.
662  *    These increase verbosity as specified in the config file.
663  * @param debug_mode: if set, do not daemonize.
664  * @param need_pidfile: if false, no pidfile is checked or created.
665  */
666 static void
667 run_daemon(const char* cfgfile, int cmdline_verbose, int debug_mode, int need_pidfile)
668 {
669 	struct config_file* cfg = NULL;
670 	struct daemon* daemon = NULL;
671 	int done_setup = 0;
672 
673 	if(!(daemon = daemon_init()))
674 		fatal_exit("alloc failure");
675 	while(!daemon->need_to_exit) {
676 		if(done_setup)
677 			verbose(VERB_OPS, "Restart of %s.", PACKAGE_STRING);
678 		else	verbose(VERB_OPS, "Start of %s.", PACKAGE_STRING);
679 
680 		/* config stuff */
681 		if(!(cfg = config_create()))
682 			fatal_exit("Could not alloc config defaults");
683 		if(!config_read(cfg, cfgfile, daemon->chroot)) {
684 			if(errno != ENOENT)
685 				fatal_exit("Could not read config file: %s."
686 					" Maybe try unbound -dd, it stays on "
687 					"the commandline to see more errors, "
688 					"or unbound-checkconf", cfgfile);
689 			log_warn("Continuing with default config settings");
690 		}
691 		apply_settings(daemon, cfg, cmdline_verbose, debug_mode);
692 		if(!done_setup)
693 			config_lookup_uid(cfg);
694 
695 		/* prepare */
696 		if(!daemon_open_shared_ports(daemon))
697 			fatal_exit("could not open ports");
698 		if(!done_setup) {
699 			perform_setup(daemon, cfg, debug_mode, &cfgfile, need_pidfile);
700 			done_setup = 1;
701 		} else {
702 			/* reopen log after HUP to facilitate log rotation */
703 			if(!cfg->use_syslog)
704 				log_init(cfg->logfile, 0, cfg->chrootdir);
705 		}
706 		/* work */
707 		daemon_fork(daemon);
708 
709 		/* clean up for restart */
710 		verbose(VERB_ALGO, "cleanup.");
711 		daemon_cleanup(daemon);
712 		config_delete(cfg);
713 	}
714 	verbose(VERB_ALGO, "Exit cleanup.");
715 	/* this unlink may not work if the pidfile is located outside
716 	 * of the chroot/workdir or we no longer have permissions */
717 	if(daemon->pidfile) {
718 		int fd;
719 		/* truncate pidfile */
720 		fd = open(daemon->pidfile, O_WRONLY | O_TRUNC, 0644);
721 		if(fd != -1)
722 			close(fd);
723 		/* delete pidfile */
724 		unlink(daemon->pidfile);
725 	}
726 	daemon_delete(daemon);
727 }
728 
729 /** getopt global, in case header files fail to declare it. */
730 extern int optind;
731 /** getopt global, in case header files fail to declare it. */
732 extern char* optarg;
733 
734 /**
735  * main program. Set options given commandline arguments.
736  * @param argc: number of commandline arguments.
737  * @param argv: array of commandline arguments.
738  * @return: exit status of the program.
739  */
740 int
741 main(int argc, char* argv[])
742 {
743 	int c;
744 	const char* cfgfile = CONFIGFILE;
745 	const char* winopt = NULL;
746 	const char* log_ident_default;
747 	int cmdline_verbose = 0;
748 	int debug_mode = 0;
749 	int need_pidfile = 1;
750 
751 #ifdef UB_ON_WINDOWS
752 	int cmdline_cfg = 0;
753 #endif
754 
755 	log_init(NULL, 0, NULL);
756 	log_ident_default = strrchr(argv[0],'/')?strrchr(argv[0],'/')+1:argv[0];
757 	log_ident_set_default(log_ident_default);
758 	log_ident_set(log_ident_default);
759 	/* parse the options */
760 	while( (c=getopt(argc, argv, "c:dhpvw:V")) != -1) {
761 		switch(c) {
762 		case 'c':
763 			cfgfile = optarg;
764 #ifdef UB_ON_WINDOWS
765 			cmdline_cfg = 1;
766 #endif
767 			break;
768 		case 'v':
769 			cmdline_verbose++;
770 			verbosity++;
771 			break;
772 		case 'p':
773 			need_pidfile = 0;
774 			break;
775 		case 'd':
776 			debug_mode++;
777 			break;
778 		case 'w':
779 			winopt = optarg;
780 			break;
781 		case 'V':
782 			print_build_options();
783 			return 0;
784 		case '?':
785 		case 'h':
786 		default:
787 			usage();
788 			return 1;
789 		}
790 	}
791 	argc -= optind;
792 	/* argv += optind; not using further arguments */
793 
794 	if(winopt) {
795 #ifdef UB_ON_WINDOWS
796 		wsvc_command_option(winopt, cfgfile, cmdline_verbose,
797 			cmdline_cfg);
798 #else
799 		fatal_exit("option not supported");
800 #endif
801 	}
802 
803 	if(argc != 0) {
804 		usage();
805 		return 1;
806 	}
807 
808 	run_daemon(cfgfile, cmdline_verbose, debug_mode, need_pidfile);
809 	log_init(NULL, 0, NULL); /* close logfile */
810 #ifndef unbound_testbound
811 	if(log_get_lock()) {
812 		lock_basic_destroy((lock_basic_type*)log_get_lock());
813 	}
814 #endif
815 	return 0;
816 }
817