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
print_build_options(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
usage(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
replay_var_compare(const void * ATTR_UNUSED (a),const void * ATTR_UNUSED (b))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
checkrlimits(struct config_file * cfg)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 size_t memsize_expect = cfg->msg_cache_size + cfg->rrset_cache_size
201 + (cfg->do_tcp?cfg->stream_wait_size:0)
202 + (cfg->ip_ratelimit?cfg->ip_ratelimit_size:0)
203 + (cfg->ratelimit?cfg->ratelimit_size:0)
204 + (cfg->dnscrypt?cfg->dnscrypt_shared_secret_cache_size + cfg->dnscrypt_nonce_cache_size:0)
205 + cfg->infra_cache_numhosts * (sizeof(struct infra_key)+sizeof(struct infra_data));
206 if(strstr(cfg->module_conf, "validator") && (cfg->trust_anchor_file_list || cfg->trust_anchor_list || cfg->auto_trust_anchor_file_list || cfg->trusted_keys_file_list)) {
207 memsize_expect += cfg->key_cache_size + cfg->neg_cache_size;
208 }
209 #ifdef HAVE_NGHTTP2_NGHTTP2_H
210 if(cfg_has_https(cfg)) {
211 memsize_expect += cfg->http_query_buffer_size + cfg->http_response_buffer_size;
212 }
213 #endif
214
215 #ifdef RLIMIT_AS
216 if(getrlimit(RLIMIT_AS, &rlim) == 0) {
217 if(rlim.rlim_cur != (rlim_t)RLIM_INFINITY &&
218 rlim.rlim_cur < (rlim_t)memsize_expect) {
219 log_warn("the ulimit(max memory size) is smaller than the expected memory usage (added size of caches). %u < %u bytes", (unsigned)rlim.rlim_cur, (unsigned)memsize_expect);
220 }
221 }
222 #endif
223 if(getrlimit(RLIMIT_DATA, &rlim) == 0) {
224 if(rlim.rlim_cur != (rlim_t)RLIM_INFINITY &&
225 rlim.rlim_cur < (rlim_t)memsize_expect) {
226 log_warn("the ulimit(data seg size) is smaller than the expected memory usage (added size of caches). %u < %u bytes", (unsigned)rlim.rlim_cur, (unsigned)memsize_expect);
227 }
228 }
229
230 if(total > 1024 &&
231 strncmp(ub_event_get_version(), "mini-event", 10) == 0) {
232 log_warn("too many file descriptors requested. The builtin"
233 "mini-event cannot handle more than 1024. Config "
234 "for less fds or compile with libevent");
235 if(numthread*perthread_noudp+15 > 1024)
236 fatal_exit("too much tcp. not enough fds.");
237 cfg->outgoing_num_ports = (int)((1024
238 - numthread*perthread_noudp
239 - 10 /* safety margin */) /numthread);
240 log_warn("continuing with less udp ports: %u",
241 cfg->outgoing_num_ports);
242 total = 1024;
243 }
244 if(perthread > 64 &&
245 strncmp(ub_event_get_version(), "winsock-event", 13) == 0) {
246 log_err("too many file descriptors requested. The winsock"
247 " event handler cannot handle more than 64 per "
248 " thread. Config for less fds");
249 if(perthread_noudp+2 > 64)
250 fatal_exit("too much tcp. not enough fds.");
251 cfg->outgoing_num_ports = (int)((64
252 - perthread_noudp
253 - 2/* safety margin */));
254 log_warn("continuing with less udp ports: %u",
255 cfg->outgoing_num_ports);
256 total = numthread*(perthread_noudp+
257 (size_t)cfg->outgoing_num_ports)+misc;
258 }
259 if(getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
260 log_warn("getrlimit: %s", strerror(errno));
261 return;
262 }
263 if(rlim.rlim_cur == (rlim_t)RLIM_INFINITY)
264 return;
265 if((size_t)rlim.rlim_cur < total) {
266 avail = (size_t)rlim.rlim_cur;
267 rlim.rlim_cur = (rlim_t)(total + 10);
268 rlim.rlim_max = (rlim_t)(total + 10);
269 #ifdef HAVE_SETRLIMIT
270 if(setrlimit(RLIMIT_NOFILE, &rlim) < 0) {
271 log_warn("setrlimit: %s", strerror(errno));
272 #endif
273 log_warn("cannot increase max open fds from %u to %u",
274 (unsigned)avail, (unsigned)total+10);
275 /* check that calculation below does not underflow,
276 * with 15 as margin */
277 if(numthread*perthread_noudp+15 > avail)
278 fatal_exit("too much tcp. not enough fds.");
279 cfg->outgoing_num_ports = (int)((avail
280 - numthread*perthread_noudp
281 - 10 /* safety margin */) /numthread);
282 log_warn("continuing with less udp ports: %u",
283 cfg->outgoing_num_ports);
284 log_warn("increase ulimit or decrease threads, "
285 "ports in config to remove this warning");
286 return;
287 #ifdef HAVE_SETRLIMIT
288 }
289 #endif
290 verbose(VERB_ALGO, "increased limit(open files) from %u to %u",
291 (unsigned)avail, (unsigned)total+10);
292 }
293 #else
294 (void)cfg;
295 #endif /* HAVE_GETRLIMIT */
296 #endif /* S_SPLINT_S */
297 }
298
299 /** set verbosity, check rlimits, cache settings */
300 static void
apply_settings(struct daemon * daemon,struct config_file * cfg,int cmdline_verbose,int debug_mode)301 apply_settings(struct daemon* daemon, struct config_file* cfg,
302 int cmdline_verbose, int debug_mode)
303 {
304 /* apply if they have changed */
305 verbosity = cmdline_verbose + cfg->verbosity;
306 if (debug_mode > 1) {
307 cfg->use_syslog = 0;
308 free(cfg->logfile);
309 cfg->logfile = NULL;
310 }
311 daemon_apply_cfg(daemon, cfg);
312 checkrlimits(cfg);
313
314 if (cfg->use_systemd && cfg->do_daemonize) {
315 log_warn("use-systemd and do-daemonize should not be enabled at the same time");
316 }
317
318 log_ident_set_or_default(cfg->log_identity);
319 }
320
321 #ifdef HAVE_KILL
322 /** Read existing pid from pidfile.
323 * @param file: file name of pid file.
324 * @return: the pid from the file or -1 if none.
325 */
326 static pid_t
readpid(const char * file)327 readpid (const char* file)
328 {
329 int fd;
330 pid_t pid;
331 char pidbuf[32];
332 char* t;
333 ssize_t l;
334
335 if ((fd = open(file, O_RDONLY)) == -1) {
336 if(errno != ENOENT)
337 log_err("Could not read pidfile %s: %s",
338 file, strerror(errno));
339 return -1;
340 }
341
342 if (((l = read(fd, pidbuf, sizeof(pidbuf)))) == -1) {
343 if(errno != ENOENT)
344 log_err("Could not read pidfile %s: %s",
345 file, strerror(errno));
346 close(fd);
347 return -1;
348 }
349
350 close(fd);
351
352 /* Empty pidfile means no pidfile... */
353 if (l == 0) {
354 return -1;
355 }
356
357 pidbuf[sizeof(pidbuf)-1] = 0;
358 pid = (pid_t)strtol(pidbuf, &t, 10);
359
360 if (*t && *t != '\n') {
361 return -1;
362 }
363 return pid;
364 }
365
366 /** write pid to file.
367 * @param pidfile: file name of pid file.
368 * @param pid: pid to write to file.
369 */
370 static void
writepid(const char * pidfile,pid_t pid)371 writepid (const char* pidfile, pid_t pid)
372 {
373 int fd;
374 char pidbuf[32];
375 size_t count = 0;
376 snprintf(pidbuf, sizeof(pidbuf), "%lu\n", (unsigned long)pid);
377
378 if((fd = open(pidfile, O_WRONLY | O_CREAT | O_TRUNC
379 #ifdef O_NOFOLLOW
380 | O_NOFOLLOW
381 #endif
382 , 0644)) == -1) {
383 log_err("cannot open pidfile %s: %s",
384 pidfile, strerror(errno));
385 return;
386 }
387 while(count < strlen(pidbuf)) {
388 ssize_t r = write(fd, pidbuf+count, strlen(pidbuf)-count);
389 if(r == -1) {
390 if(errno == EAGAIN || errno == EINTR)
391 continue;
392 log_err("cannot write to pidfile %s: %s",
393 pidfile, strerror(errno));
394 close(fd);
395 return;
396 } else if(r == 0) {
397 log_err("cannot write any bytes to pidfile %s: "
398 "write returns 0 bytes written", pidfile);
399 close(fd);
400 return;
401 }
402 count += r;
403 }
404 close(fd);
405 }
406
407 /**
408 * check old pid file.
409 * @param pidfile: the file name of the pid file.
410 * @param inchroot: if pidfile is inchroot and we can thus expect to
411 * be able to delete it.
412 */
413 static void
checkoldpid(char * pidfile,int inchroot)414 checkoldpid(char* pidfile, int inchroot)
415 {
416 pid_t old;
417 if((old = readpid(pidfile)) != -1) {
418 /* see if it is still alive */
419 if(kill(old, 0) == 0 || errno == EPERM)
420 log_warn("unbound is already running as pid %u.",
421 (unsigned)old);
422 else if(inchroot)
423 log_warn("did not exit gracefully last time (%u)",
424 (unsigned)old);
425 }
426 }
427 #endif /* HAVE_KILL */
428
429 /** detach from command line */
430 static void
detach(void)431 detach(void)
432 {
433 #if defined(HAVE_DAEMON) && !defined(DEPRECATED_DAEMON)
434 /* use POSIX daemon(3) function */
435 if(daemon(1, 0) != 0)
436 fatal_exit("daemon failed: %s", strerror(errno));
437 #else /* no HAVE_DAEMON */
438 #ifdef HAVE_FORK
439 int fd;
440 /* Take off... */
441 switch (fork()) {
442 case 0:
443 break;
444 case -1:
445 fatal_exit("fork failed: %s", strerror(errno));
446 default:
447 /* exit interactive session */
448 exit(0);
449 }
450 /* detach */
451 #ifdef HAVE_SETSID
452 if(setsid() == -1)
453 fatal_exit("setsid() failed: %s", strerror(errno));
454 #endif
455 if ((fd = open("/dev/null", O_RDWR, 0)) != -1) {
456 (void)dup2(fd, STDIN_FILENO);
457 (void)dup2(fd, STDOUT_FILENO);
458 (void)dup2(fd, STDERR_FILENO);
459 if (fd > 2)
460 (void)close(fd);
461 }
462 #endif /* HAVE_FORK */
463 #endif /* HAVE_DAEMON */
464 }
465
466 /** daemonize, drop user privileges and chroot if needed */
467 static void
perform_setup(struct daemon * daemon,struct config_file * cfg,int debug_mode,const char ** cfgfile,int need_pidfile)468 perform_setup(struct daemon* daemon, struct config_file* cfg, int debug_mode,
469 const char** cfgfile, int need_pidfile)
470 {
471 #ifdef HAVE_KILL
472 int pidinchroot;
473 #endif
474 #ifdef HAVE_GETPWNAM
475 struct passwd *pwd = NULL;
476 #endif
477
478 if(!daemon_privileged(daemon))
479 fatal_exit("could not do privileged setup");
480 #ifdef HAVE_GETPWNAM
481 if(cfg->username && cfg->username[0]) {
482 if((pwd = getpwnam(cfg->username)) == NULL)
483 fatal_exit("user '%s' does not exist.", cfg->username);
484 /* endpwent below, in case we need pwd for setusercontext */
485 }
486 #endif
487 #ifdef UB_ON_WINDOWS
488 w_config_adjust_directory(cfg);
489 #endif
490
491 /* read ssl keys while superuser and outside chroot */
492 #ifdef HAVE_SSL
493 if(!(daemon->rc = daemon_remote_create(cfg)))
494 fatal_exit("could not set up remote-control");
495 if(cfg->ssl_service_key && cfg->ssl_service_key[0]) {
496 if(!(daemon->listen_sslctx = listen_sslctx_create(
497 cfg->ssl_service_key, cfg->ssl_service_pem, NULL)))
498 fatal_exit("could not set up listen SSL_CTX");
499 if(cfg->tls_ciphers && cfg->tls_ciphers[0]) {
500 if (!SSL_CTX_set_cipher_list(daemon->listen_sslctx, cfg->tls_ciphers)) {
501 fatal_exit("failed to set tls-cipher %s", cfg->tls_ciphers);
502 }
503 }
504 #ifdef HAVE_SSL_CTX_SET_CIPHERSUITES
505 if(cfg->tls_ciphersuites && cfg->tls_ciphersuites[0]) {
506 if (!SSL_CTX_set_ciphersuites(daemon->listen_sslctx, cfg->tls_ciphersuites)) {
507 fatal_exit("failed to set tls-ciphersuites %s", cfg->tls_ciphersuites);
508 }
509 }
510 #endif
511 if(cfg->tls_session_ticket_keys.first &&
512 cfg->tls_session_ticket_keys.first->str[0] != 0) {
513 if(!listen_sslctx_setup_ticket_keys(daemon->listen_sslctx, cfg->tls_session_ticket_keys.first)) {
514 fatal_exit("could not set session ticket SSL_CTX");
515 }
516 }
517 }
518 if(!(daemon->connect_sslctx = connect_sslctx_create(NULL, NULL,
519 cfg->tls_cert_bundle, cfg->tls_win_cert)))
520 fatal_exit("could not set up connect SSL_CTX");
521 #endif
522
523 /* init syslog (as root) if needed, before daemonize, otherwise
524 * a fork error could not be printed since daemonize closed stderr.*/
525 if(cfg->use_syslog) {
526 log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir);
527 }
528 /* if using a logfile, we cannot open it because the logfile would
529 * be created with the wrong permissions, we cannot chown it because
530 * we cannot chown system logfiles, so we do not open at all.
531 * So, using a logfile, the user does not see errors unless -d is
532 * given to unbound on the commandline. */
533
534 #ifdef HAVE_KILL
535 /* true if pidfile is inside chrootdir, or nochroot */
536 pidinchroot = need_pidfile && (!(cfg->chrootdir && cfg->chrootdir[0]) ||
537 (cfg->chrootdir && cfg->chrootdir[0] &&
538 strncmp(cfg->pidfile, cfg->chrootdir,
539 strlen(cfg->chrootdir))==0));
540
541 /* check old pid file before forking */
542 if(cfg->pidfile && cfg->pidfile[0] && need_pidfile) {
543 /* calculate position of pidfile */
544 if(cfg->pidfile[0] == '/')
545 daemon->pidfile = strdup(cfg->pidfile);
546 else daemon->pidfile = fname_after_chroot(cfg->pidfile,
547 cfg, 1);
548 if(!daemon->pidfile)
549 fatal_exit("pidfile alloc: out of memory");
550 /* Check old pid if there is no username configured.
551 * With a username, the assumption is that the privilege
552 * drop makes a pidfile not removed when the server stopped
553 * last time. The server does not chown the pidfile for it,
554 * because that creates privilege escape problems, with the
555 * pidfile writable by unprivileged users, but used by
556 * privileged users. */
557 if(!(cfg->username && cfg->username[0]))
558 checkoldpid(daemon->pidfile, pidinchroot);
559 }
560 #endif
561
562 /* daemonize because pid is needed by the writepid func */
563 if(!debug_mode && cfg->do_daemonize) {
564 detach();
565 }
566
567 /* write new pidfile (while still root, so can be outside chroot) */
568 #ifdef HAVE_KILL
569 if(cfg->pidfile && cfg->pidfile[0] && need_pidfile) {
570 writepid(daemon->pidfile, getpid());
571 }
572 #else
573 (void)daemon;
574 (void)need_pidfile;
575 #endif /* HAVE_KILL */
576
577 /* Set user context */
578 #ifdef HAVE_GETPWNAM
579 if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) {
580 #ifdef HAVE_SETUSERCONTEXT
581 /* setusercontext does initgroups, setuid, setgid, and
582 * also resource limits from login config, but we
583 * still call setresuid, setresgid to be sure to set all uid*/
584 if(setusercontext(NULL, pwd, cfg_uid, (unsigned)
585 LOGIN_SETALL & ~LOGIN_SETUSER & ~LOGIN_SETGROUP) != 0)
586 log_warn("unable to setusercontext %s: %s",
587 cfg->username, strerror(errno));
588 #else
589 (void)pwd;
590 #endif /* HAVE_SETUSERCONTEXT */
591 }
592 #endif /* HAVE_GETPWNAM */
593
594 /* box into the chroot */
595 #ifdef HAVE_CHROOT
596 if(cfg->chrootdir && cfg->chrootdir[0]) {
597 if(chdir(cfg->chrootdir)) {
598 fatal_exit("unable to chdir to chroot %s: %s",
599 cfg->chrootdir, strerror(errno));
600 }
601 verbose(VERB_QUERY, "chdir to %s", cfg->chrootdir);
602 if(chroot(cfg->chrootdir))
603 fatal_exit("unable to chroot to %s: %s",
604 cfg->chrootdir, strerror(errno));
605 if(chdir("/"))
606 fatal_exit("unable to chdir to / in chroot %s: %s",
607 cfg->chrootdir, strerror(errno));
608 verbose(VERB_QUERY, "chroot to %s", cfg->chrootdir);
609 if(strncmp(*cfgfile, cfg->chrootdir,
610 strlen(cfg->chrootdir)) == 0)
611 (*cfgfile) += strlen(cfg->chrootdir);
612
613 /* adjust stored pidfile for chroot */
614 if(daemon->pidfile && daemon->pidfile[0] &&
615 strncmp(daemon->pidfile, cfg->chrootdir,
616 strlen(cfg->chrootdir))==0) {
617 char* old = daemon->pidfile;
618 daemon->pidfile = strdup(old+strlen(cfg->chrootdir));
619 free(old);
620 if(!daemon->pidfile)
621 log_err("out of memory in pidfile adjust");
622 }
623 daemon->chroot = strdup(cfg->chrootdir);
624 if(!daemon->chroot)
625 log_err("out of memory in daemon chroot dir storage");
626 }
627 #else
628 (void)cfgfile;
629 #endif
630 /* change to working directory inside chroot */
631 if(cfg->directory && cfg->directory[0]) {
632 char* dir = cfg->directory;
633 if(cfg->chrootdir && cfg->chrootdir[0] &&
634 strncmp(dir, cfg->chrootdir,
635 strlen(cfg->chrootdir)) == 0)
636 dir += strlen(cfg->chrootdir);
637 if(dir[0]) {
638 if(chdir(dir)) {
639 fatal_exit("Could not chdir to %s: %s",
640 dir, strerror(errno));
641 }
642 verbose(VERB_QUERY, "chdir to %s", dir);
643 }
644 }
645
646 /* drop permissions after chroot, getpwnam, pidfile, syslog done*/
647 #ifdef HAVE_GETPWNAM
648 if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) {
649 # ifdef HAVE_INITGROUPS
650 if(initgroups(cfg->username, cfg_gid) != 0)
651 log_warn("unable to initgroups %s: %s",
652 cfg->username, strerror(errno));
653 # endif /* HAVE_INITGROUPS */
654 # ifdef HAVE_ENDPWENT
655 endpwent();
656 # endif
657
658 #ifdef HAVE_SETRESGID
659 if(setresgid(cfg_gid,cfg_gid,cfg_gid) != 0)
660 #elif defined(HAVE_SETREGID) && !defined(DARWIN_BROKEN_SETREUID)
661 if(setregid(cfg_gid,cfg_gid) != 0)
662 #else /* use setgid */
663 if(setgid(cfg_gid) != 0)
664 #endif /* HAVE_SETRESGID */
665 fatal_exit("unable to set group id of %s: %s",
666 cfg->username, strerror(errno));
667 #ifdef HAVE_SETRESUID
668 if(setresuid(cfg_uid,cfg_uid,cfg_uid) != 0)
669 #elif defined(HAVE_SETREUID) && !defined(DARWIN_BROKEN_SETREUID)
670 if(setreuid(cfg_uid,cfg_uid) != 0)
671 #else /* use setuid */
672 if(setuid(cfg_uid) != 0)
673 #endif /* HAVE_SETRESUID */
674 fatal_exit("unable to set user id of %s: %s",
675 cfg->username, strerror(errno));
676 verbose(VERB_QUERY, "drop user privileges, run as %s",
677 cfg->username);
678 }
679 #endif /* HAVE_GETPWNAM */
680 /* file logging inited after chroot,chdir,setuid is done so that
681 * it would succeed on SIGHUP as well */
682 if(!cfg->use_syslog)
683 log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir);
684 }
685
686 /**
687 * Run the daemon.
688 * @param cfgfile: the config file name.
689 * @param cmdline_verbose: verbosity resulting from commandline -v.
690 * These increase verbosity as specified in the config file.
691 * @param debug_mode: if set, do not daemonize.
692 * @param need_pidfile: if false, no pidfile is checked or created.
693 */
694 static void
run_daemon(const char * cfgfile,int cmdline_verbose,int debug_mode,int need_pidfile)695 run_daemon(const char* cfgfile, int cmdline_verbose, int debug_mode, int need_pidfile)
696 {
697 struct config_file* cfg = NULL;
698 struct daemon* daemon = NULL;
699 int done_setup = 0;
700
701 if(!(daemon = daemon_init()))
702 fatal_exit("alloc failure");
703 while(!daemon->need_to_exit) {
704 if(done_setup)
705 verbose(VERB_OPS, "Restart of %s.", PACKAGE_STRING);
706 else verbose(VERB_OPS, "Start of %s.", PACKAGE_STRING);
707
708 /* config stuff */
709 if(!(cfg = config_create()))
710 fatal_exit("Could not alloc config defaults");
711 if(!config_read(cfg, cfgfile, daemon->chroot)) {
712 if(errno != ENOENT)
713 fatal_exit("Could not read config file: %s."
714 " Maybe try unbound -dd, it stays on "
715 "the commandline to see more errors, "
716 "or unbound-checkconf", cfgfile);
717 log_warn("Continuing with default config settings");
718 }
719 apply_settings(daemon, cfg, cmdline_verbose, debug_mode);
720 if(!done_setup)
721 config_lookup_uid(cfg);
722
723 /* prepare */
724 if(!daemon_open_shared_ports(daemon))
725 fatal_exit("could not open ports");
726 if(!done_setup) {
727 perform_setup(daemon, cfg, debug_mode, &cfgfile, need_pidfile);
728 done_setup = 1;
729 } else {
730 /* reopen log after HUP to facilitate log rotation */
731 if(!cfg->use_syslog)
732 log_init(cfg->logfile, 0, cfg->chrootdir);
733 }
734 /* work */
735 daemon_fork(daemon);
736
737 /* clean up for restart */
738 verbose(VERB_ALGO, "cleanup.");
739 daemon_cleanup(daemon);
740 config_delete(cfg);
741 }
742 verbose(VERB_ALGO, "Exit cleanup.");
743 /* this unlink may not work if the pidfile is located outside
744 * of the chroot/workdir or we no longer have permissions */
745 if(daemon->pidfile) {
746 int fd;
747 /* truncate pidfile */
748 fd = open(daemon->pidfile, O_WRONLY | O_TRUNC
749 #ifdef O_NOFOLLOW
750 | O_NOFOLLOW
751 #endif
752 , 0644);
753 if(fd != -1)
754 close(fd);
755 /* delete pidfile */
756 unlink(daemon->pidfile);
757 }
758 daemon_delete(daemon);
759 }
760
761 /** getopt global, in case header files fail to declare it. */
762 extern int optind;
763 /** getopt global, in case header files fail to declare it. */
764 extern char* optarg;
765
766 /**
767 * main program. Set options given commandline arguments.
768 * @param argc: number of commandline arguments.
769 * @param argv: array of commandline arguments.
770 * @return: exit status of the program.
771 */
772 int
main(int argc,char * argv[])773 main(int argc, char* argv[])
774 {
775 int c;
776 const char* cfgfile = CONFIGFILE;
777 const char* winopt = NULL;
778 const char* log_ident_default;
779 int cmdline_verbose = 0;
780 int debug_mode = 0;
781 int need_pidfile = 1;
782
783 #ifdef UB_ON_WINDOWS
784 int cmdline_cfg = 0;
785 #endif
786
787 checklock_start();
788 log_init(NULL, 0, NULL);
789 log_ident_default = strrchr(argv[0],'/')?strrchr(argv[0],'/')+1:argv[0];
790 log_ident_set_default(log_ident_default);
791 log_ident_set(log_ident_default);
792 /* parse the options */
793 while( (c=getopt(argc, argv, "c:dhpvw:V")) != -1) {
794 switch(c) {
795 case 'c':
796 cfgfile = optarg;
797 #ifdef UB_ON_WINDOWS
798 cmdline_cfg = 1;
799 #endif
800 break;
801 case 'v':
802 cmdline_verbose++;
803 verbosity++;
804 break;
805 case 'p':
806 need_pidfile = 0;
807 break;
808 case 'd':
809 debug_mode++;
810 break;
811 case 'w':
812 winopt = optarg;
813 break;
814 case 'V':
815 print_build_options();
816 return 0;
817 case '?':
818 case 'h':
819 default:
820 usage();
821 return 1;
822 }
823 }
824 argc -= optind;
825 /* argv += optind; not using further arguments */
826
827 if(winopt) {
828 #ifdef UB_ON_WINDOWS
829 wsvc_command_option(winopt, cfgfile, cmdline_verbose,
830 cmdline_cfg);
831 #else
832 fatal_exit("option not supported");
833 #endif
834 }
835
836 if(argc != 0) {
837 usage();
838 return 1;
839 }
840
841 run_daemon(cfgfile, cmdline_verbose, debug_mode, need_pidfile);
842 log_init(NULL, 0, NULL); /* close logfile */
843 #ifndef unbound_testbound
844 if(log_get_lock()) {
845 lock_basic_destroy((lock_basic_type*)log_get_lock());
846 }
847 #endif
848 return 0;
849 }
850