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 #if defined(HAVE_GETRLIMIT) && !defined(unbound_testbound)
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 #ifdef HAVE_SSL
467 /* setup a listening ssl context, fatal_exit() on any failure */
468 static void
setup_listen_sslctx(void ** ctx,int is_dot,int is_doh,struct config_file * cfg)469 setup_listen_sslctx(void** ctx, int is_dot, int is_doh, struct config_file* cfg)
470 {
471 if(!(*ctx = listen_sslctx_create(
472 cfg->ssl_service_key, cfg->ssl_service_pem, NULL,
473 cfg->tls_ciphers, cfg->tls_ciphersuites,
474 (cfg->tls_session_ticket_keys.first &&
475 cfg->tls_session_ticket_keys.first->str[0] != 0),
476 is_dot, is_doh))) {
477 fatal_exit("could not set up listen SSL_CTX");
478 }
479 }
480 #endif /* HAVE_SSL */
481
482 /* setups the needed ssl contexts, fatal_exit() on any failure */
483 static void
setup_sslctxs(struct daemon * daemon,struct config_file * cfg)484 setup_sslctxs(struct daemon* daemon, struct config_file* cfg)
485 {
486 #ifdef HAVE_SSL
487 if(!(daemon->rc = daemon_remote_create(cfg)))
488 fatal_exit("could not set up remote-control");
489 if(cfg->ssl_service_key && cfg->ssl_service_key[0]) {
490 /* setup the session keys; the callback to use them will be
491 * attached to each sslctx separately */
492 if(cfg->tls_session_ticket_keys.first &&
493 cfg->tls_session_ticket_keys.first->str[0] != 0) {
494 if(!listen_sslctx_setup_ticket_keys(
495 cfg->tls_session_ticket_keys.first)) {
496 fatal_exit("could not set session ticket SSL_CTX");
497 }
498 }
499 (void)setup_listen_sslctx(&daemon->listen_dot_sslctx, 1, 0, cfg);
500 #ifdef HAVE_NGHTTP2_NGHTTP2_H
501 if(cfg_has_https(cfg)) {
502 (void)setup_listen_sslctx(&daemon->listen_doh_sslctx, 0, 1, cfg);
503 }
504 #endif
505 #ifdef HAVE_NGTCP2
506 if(cfg_has_quic(cfg)) {
507 if(!(daemon->listen_quic_sslctx = quic_sslctx_create(
508 cfg->ssl_service_key, cfg->ssl_service_pem, NULL))) {
509 fatal_exit("could not set up quic SSL_CTX");
510 }
511 }
512 #endif /* HAVE_NGTCP2 */
513 }
514 if(!(daemon->connect_dot_sslctx = connect_sslctx_create(NULL, NULL,
515 cfg->tls_cert_bundle, cfg->tls_win_cert)))
516 fatal_exit("could not set up connect SSL_CTX");
517 #else /* HAVE_SSL */
518 (void)daemon;(void)cfg;
519 #endif /* HAVE_SSL */
520 }
521
522 /** daemonize, drop user privileges and chroot if needed */
523 static void
perform_setup(struct daemon * daemon,struct config_file * cfg,int debug_mode,const char ** cfgfile,int need_pidfile)524 perform_setup(struct daemon* daemon, struct config_file* cfg, int debug_mode,
525 const char** cfgfile, int need_pidfile)
526 {
527 #ifdef HAVE_KILL
528 int pidinchroot;
529 #endif
530 #ifdef HAVE_GETPWNAM
531 struct passwd *pwd = NULL;
532 #endif
533
534 if(!daemon_privileged(daemon))
535 fatal_exit("could not do privileged setup");
536 #ifdef HAVE_GETPWNAM
537 if(cfg->username && cfg->username[0]) {
538 if((pwd = getpwnam(cfg->username)) == NULL)
539 fatal_exit("user '%s' does not exist.", cfg->username);
540 /* endpwent below, in case we need pwd for setusercontext */
541 }
542 #endif
543 #ifdef UB_ON_WINDOWS
544 w_config_adjust_directory(cfg);
545 #endif
546
547 /* read ssl keys while superuser and outside chroot */
548 (void)setup_sslctxs(daemon, cfg);
549
550 /* init syslog (as root) if needed, before daemonize, otherwise
551 * a fork error could not be printed since daemonize closed stderr.*/
552 if(cfg->use_syslog) {
553 log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir);
554 }
555 /* if using a logfile, we cannot open it because the logfile would
556 * be created with the wrong permissions, we cannot chown it because
557 * we cannot chown system logfiles, so we do not open at all.
558 * So, using a logfile, the user does not see errors unless -d is
559 * given to unbound on the commandline. */
560
561 #ifdef HAVE_KILL
562 /* true if pidfile is inside chrootdir, or nochroot */
563 pidinchroot = need_pidfile && (!(cfg->chrootdir && cfg->chrootdir[0]) ||
564 (cfg->chrootdir && cfg->chrootdir[0] &&
565 strncmp(cfg->pidfile, cfg->chrootdir,
566 strlen(cfg->chrootdir))==0));
567
568 /* check old pid file before forking */
569 if(cfg->pidfile && cfg->pidfile[0] && need_pidfile) {
570 /* calculate position of pidfile */
571 if(cfg->pidfile[0] == '/')
572 daemon->pidfile = strdup(cfg->pidfile);
573 else daemon->pidfile = fname_after_chroot(cfg->pidfile,
574 cfg, 1);
575 if(!daemon->pidfile)
576 fatal_exit("pidfile alloc: out of memory");
577 /* Check old pid if there is no username configured.
578 * With a username, the assumption is that the privilege
579 * drop makes a pidfile not removed when the server stopped
580 * last time. The server does not chown the pidfile for it,
581 * because that creates privilege escape problems, with the
582 * pidfile writable by unprivileged users, but used by
583 * privileged users. */
584 if(!(cfg->username && cfg->username[0]))
585 checkoldpid(daemon->pidfile, pidinchroot);
586 }
587 #endif
588
589 /* daemonize because pid is needed by the writepid func */
590 if(!debug_mode && cfg->do_daemonize) {
591 detach();
592 }
593
594 /* write new pidfile (while still root, so can be outside chroot) */
595 #ifdef HAVE_KILL
596 if(cfg->pidfile && cfg->pidfile[0] && need_pidfile) {
597 writepid(daemon->pidfile, getpid());
598 }
599 #else
600 (void)daemon;
601 (void)need_pidfile;
602 #endif /* HAVE_KILL */
603
604 /* Set user context */
605 #ifdef HAVE_GETPWNAM
606 if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) {
607 #ifdef HAVE_SETUSERCONTEXT
608 /* setusercontext does initgroups, setuid, setgid, and
609 * also resource limits from login config, but we
610 * still call setresuid, setresgid to be sure to set all uid*/
611 if(setusercontext(NULL, pwd, cfg_uid, (unsigned)
612 LOGIN_SETALL & ~LOGIN_SETUSER & ~LOGIN_SETGROUP) != 0)
613 log_warn("unable to setusercontext %s: %s",
614 cfg->username, strerror(errno));
615 #else
616 (void)pwd;
617 #endif /* HAVE_SETUSERCONTEXT */
618 }
619 #endif /* HAVE_GETPWNAM */
620
621 /* box into the chroot */
622 #ifdef HAVE_CHROOT
623 if(cfg->chrootdir && cfg->chrootdir[0]) {
624 if(chdir(cfg->chrootdir)) {
625 fatal_exit("unable to chdir to chroot %s: %s",
626 cfg->chrootdir, strerror(errno));
627 }
628 verbose(VERB_QUERY, "chdir to %s", cfg->chrootdir);
629 if(chroot(cfg->chrootdir))
630 fatal_exit("unable to chroot to %s: %s",
631 cfg->chrootdir, strerror(errno));
632 if(chdir("/"))
633 fatal_exit("unable to chdir to / in chroot %s: %s",
634 cfg->chrootdir, strerror(errno));
635 verbose(VERB_QUERY, "chroot to %s", cfg->chrootdir);
636 if(strncmp(*cfgfile, cfg->chrootdir,
637 strlen(cfg->chrootdir)) == 0)
638 (*cfgfile) += strlen(cfg->chrootdir);
639
640 /* adjust stored pidfile for chroot */
641 if(daemon->pidfile && daemon->pidfile[0] &&
642 strncmp(daemon->pidfile, cfg->chrootdir,
643 strlen(cfg->chrootdir))==0) {
644 char* old = daemon->pidfile;
645 daemon->pidfile = strdup(old+strlen(cfg->chrootdir));
646 free(old);
647 if(!daemon->pidfile)
648 log_err("out of memory in pidfile adjust");
649 }
650 daemon->chroot = strdup(cfg->chrootdir);
651 if(!daemon->chroot)
652 log_err("out of memory in daemon chroot dir storage");
653 }
654 #else
655 (void)cfgfile;
656 #endif
657 /* change to working directory inside chroot */
658 if(cfg->directory && cfg->directory[0]) {
659 char* dir = cfg->directory;
660 if(cfg->chrootdir && cfg->chrootdir[0] &&
661 strncmp(dir, cfg->chrootdir,
662 strlen(cfg->chrootdir)) == 0)
663 dir += strlen(cfg->chrootdir);
664 if(dir[0]) {
665 if(chdir(dir)) {
666 fatal_exit("Could not chdir to %s: %s",
667 dir, strerror(errno));
668 }
669 verbose(VERB_QUERY, "chdir to %s", dir);
670 }
671 }
672
673 /* drop permissions after chroot, getpwnam, pidfile, syslog done*/
674 #ifdef HAVE_GETPWNAM
675 if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) {
676 # ifdef HAVE_INITGROUPS
677 if(initgroups(cfg->username, cfg_gid) != 0)
678 log_warn("unable to initgroups %s: %s",
679 cfg->username, strerror(errno));
680 # endif /* HAVE_INITGROUPS */
681 # ifdef HAVE_ENDPWENT
682 endpwent();
683 # endif
684
685 #ifdef HAVE_SETRESGID
686 if(setresgid(cfg_gid,cfg_gid,cfg_gid) != 0)
687 #elif defined(HAVE_SETREGID) && !defined(DARWIN_BROKEN_SETREUID)
688 if(setregid(cfg_gid,cfg_gid) != 0)
689 #else /* use setgid */
690 if(setgid(cfg_gid) != 0)
691 #endif /* HAVE_SETRESGID */
692 fatal_exit("unable to set group id of %s: %s",
693 cfg->username, strerror(errno));
694 #ifdef HAVE_SETRESUID
695 if(setresuid(cfg_uid,cfg_uid,cfg_uid) != 0)
696 #elif defined(HAVE_SETREUID) && !defined(DARWIN_BROKEN_SETREUID)
697 if(setreuid(cfg_uid,cfg_uid) != 0)
698 #else /* use setuid */
699 if(setuid(cfg_uid) != 0)
700 #endif /* HAVE_SETRESUID */
701 fatal_exit("unable to set user id of %s: %s",
702 cfg->username, strerror(errno));
703 verbose(VERB_QUERY, "drop user privileges, run as %s",
704 cfg->username);
705 }
706 #endif /* HAVE_GETPWNAM */
707 /* file logging inited after chroot,chdir,setuid is done so that
708 * it would succeed on SIGHUP as well */
709 if(!cfg->use_syslog)
710 log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir);
711 daemon->cfgfile = strdup(*cfgfile);
712 if(!daemon->cfgfile)
713 fatal_exit("out of memory in daemon cfgfile strdup");
714 }
715
716 /**
717 * Run the daemon.
718 * @param cfgfile: the config file name.
719 * @param cmdline_verbose: verbosity resulting from commandline -v.
720 * These increase verbosity as specified in the config file.
721 * @param debug_mode: if set, do not daemonize.
722 * @param need_pidfile: if false, no pidfile is checked or created.
723 */
724 static void
run_daemon(const char * cfgfile,int cmdline_verbose,int debug_mode,int need_pidfile)725 run_daemon(const char* cfgfile, int cmdline_verbose, int debug_mode, int need_pidfile)
726 {
727 struct config_file* cfg = NULL;
728 struct daemon* daemon = NULL;
729 int done_setup = 0;
730
731 if(!(daemon = daemon_init()))
732 fatal_exit("alloc failure");
733 while(!daemon->need_to_exit) {
734 if(done_setup)
735 verbose(VERB_OPS, "Restart of %s.", PACKAGE_STRING);
736 else verbose(VERB_OPS, "Start of %s.", PACKAGE_STRING);
737
738 /* config stuff */
739 if(!(cfg = config_create()))
740 fatal_exit("Could not alloc config defaults");
741 if(!config_read(cfg, cfgfile, daemon->chroot)) {
742 if(errno != ENOENT)
743 fatal_exit("Could not read config file: %s."
744 " Maybe try unbound -dd, it stays on "
745 "the commandline to see more errors, "
746 "or unbound-checkconf", cfgfile);
747 log_warn("Continuing with default config settings");
748 config_auto_slab_values(cfg);
749 }
750 apply_settings(daemon, cfg, cmdline_verbose, debug_mode);
751 if(!done_setup)
752 config_lookup_uid(cfg);
753
754 /* prepare */
755 if(!daemon_open_shared_ports(daemon))
756 fatal_exit("could not open ports");
757 if(!done_setup) {
758 perform_setup(daemon, cfg, debug_mode, &cfgfile, need_pidfile);
759 done_setup = 1;
760 } else {
761 /* reopen log after HUP to facilitate log rotation */
762 if(!cfg->use_syslog)
763 log_init(cfg->logfile, 0, cfg->chrootdir);
764 }
765 /* work */
766 daemon_fork(daemon);
767
768 /* clean up for restart */
769 verbose(VERB_ALGO, "cleanup.");
770 daemon_cleanup(daemon);
771 config_delete(cfg);
772 }
773 verbose(VERB_ALGO, "Exit cleanup.");
774 /* this unlink may not work if the pidfile is located outside
775 * of the chroot/workdir or we no longer have permissions */
776 if(daemon->pidfile) {
777 int fd;
778 /* truncate pidfile */
779 fd = open(daemon->pidfile, O_WRONLY | O_TRUNC
780 #ifdef O_NOFOLLOW
781 | O_NOFOLLOW
782 #endif
783 , 0644);
784 if(fd != -1)
785 close(fd);
786 /* delete pidfile */
787 unlink(daemon->pidfile);
788 }
789 daemon_delete(daemon);
790 }
791
792 /** getopt global, in case header files fail to declare it. */
793 extern int optind;
794 /** getopt global, in case header files fail to declare it. */
795 extern char* optarg;
796
797 /**
798 * main program. Set options given commandline arguments.
799 * @param argc: number of commandline arguments.
800 * @param argv: array of commandline arguments.
801 * @return: exit status of the program.
802 */
803 int
main(int argc,char * argv[])804 main(int argc, char* argv[])
805 {
806 int c;
807 const char* cfgfile = CONFIGFILE;
808 const char* winopt = NULL;
809 const char* log_ident_default;
810 int cmdline_verbose = 0;
811 int debug_mode = 0;
812 int need_pidfile = 1;
813
814 #ifdef UB_ON_WINDOWS
815 int cmdline_cfg = 0;
816 #endif
817
818 checklock_start();
819 log_init(NULL, 0, NULL);
820 log_ident_default = strrchr(argv[0],'/')?strrchr(argv[0],'/')+1:argv[0];
821 log_ident_set_default(log_ident_default);
822 log_ident_set(log_ident_default);
823 /* parse the options */
824 while( (c=getopt(argc, argv, "c:dhpvw:V")) != -1) {
825 switch(c) {
826 case 'c':
827 cfgfile = optarg;
828 #ifdef UB_ON_WINDOWS
829 cmdline_cfg = 1;
830 #endif
831 break;
832 case 'v':
833 cmdline_verbose++;
834 verbosity++;
835 break;
836 case 'p':
837 need_pidfile = 0;
838 break;
839 case 'd':
840 debug_mode++;
841 break;
842 case 'w':
843 winopt = optarg;
844 break;
845 case 'V':
846 print_build_options();
847 return 0;
848 case '?':
849 case 'h':
850 default:
851 usage();
852 return 1;
853 }
854 }
855 argc -= optind;
856 /* argv += optind; not using further arguments */
857
858 if(winopt) {
859 #ifdef UB_ON_WINDOWS
860 wsvc_command_option(winopt, cfgfile, cmdline_verbose,
861 cmdline_cfg);
862 #else
863 fatal_exit("option not supported");
864 #endif
865 }
866
867 if(argc != 0) {
868 usage();
869 return 1;
870 }
871
872 run_daemon(cfgfile, cmdline_verbose, debug_mode, need_pidfile);
873 log_init(NULL, 0, NULL); /* close logfile */
874 #ifndef unbound_testbound
875 if(log_get_lock()) {
876 lock_basic_destroy((lock_basic_type*)log_get_lock());
877 }
878 #endif
879 return 0;
880 }
881