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 <signal.h> 61 #include <fcntl.h> 62 #include <openssl/crypto.h> 63 #ifdef HAVE_PWD_H 64 #include <pwd.h> 65 #endif 66 #ifdef HAVE_GRP_H 67 #include <grp.h> 68 #endif 69 70 #ifndef S_SPLINT_S 71 /* splint chokes on this system header file */ 72 #ifdef HAVE_SYS_RESOURCE_H 73 #include <sys/resource.h> 74 #endif 75 #endif /* S_SPLINT_S */ 76 #ifdef HAVE_LOGIN_CAP_H 77 #include <login_cap.h> 78 #endif 79 80 #ifdef USE_MINI_EVENT 81 # ifdef USE_WINSOCK 82 # include "util/winsock_event.h" 83 # else 84 # include "util/mini_event.h" 85 # endif 86 #else 87 # ifdef HAVE_EVENT_H 88 # include <event.h> 89 # else 90 # include "event2/event.h" 91 # include "event2/event_struct.h" 92 # include "event2/event_compat.h" 93 # endif 94 #endif 95 96 #ifdef UB_ON_WINDOWS 97 # include "winrc/win_svc.h" 98 #endif 99 100 #ifdef HAVE_NSS 101 /* nss3 */ 102 # include "nss.h" 103 #endif 104 105 #ifdef HAVE_SBRK 106 /** global debug value to keep track of heap memory allocation */ 107 void* unbound_start_brk = 0; 108 #endif 109 110 #if !defined(HAVE_EVENT_BASE_GET_METHOD) && (defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)) 111 static const char* ev_backend2str(int b) 112 { 113 switch(b) { 114 case EVBACKEND_SELECT: return "select"; 115 case EVBACKEND_POLL: return "poll"; 116 case EVBACKEND_EPOLL: return "epoll"; 117 case EVBACKEND_KQUEUE: return "kqueue"; 118 case EVBACKEND_DEVPOLL: return "devpoll"; 119 case EVBACKEND_PORT: return "evport"; 120 } 121 return "unknown"; 122 } 123 #endif 124 125 /** get the event system in use */ 126 static void get_event_sys(const char** n, const char** s, const char** m) 127 { 128 #ifdef USE_WINSOCK 129 *n = "event"; 130 *s = "winsock"; 131 *m = "WSAWaitForMultipleEvents"; 132 #elif defined(USE_MINI_EVENT) 133 *n = "mini-event"; 134 *s = "internal"; 135 *m = "select"; 136 #else 137 struct event_base* b; 138 *s = event_get_version(); 139 # ifdef HAVE_EVENT_BASE_GET_METHOD 140 *n = "libevent"; 141 b = event_base_new(); 142 *m = event_base_get_method(b); 143 # elif defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP) 144 *n = "libev"; 145 b = (struct event_base*)ev_default_loop(EVFLAG_AUTO); 146 *m = ev_backend2str(ev_backend((struct ev_loop*)b)); 147 # else 148 *n = "unknown"; 149 *m = "not obtainable"; 150 b = NULL; 151 # endif 152 # ifdef HAVE_EVENT_BASE_FREE 153 event_base_free(b); 154 # endif 155 #endif 156 } 157 158 /** print usage. */ 159 static void usage() 160 { 161 const char** m; 162 const char *evnm="event", *evsys="", *evmethod=""; 163 printf("usage: unbound [options]\n"); 164 printf(" start unbound daemon DNS resolver.\n"); 165 printf("-h this help\n"); 166 printf("-c file config file to read instead of %s\n", CONFIGFILE); 167 printf(" file format is described in unbound.conf(5).\n"); 168 printf("-d do not fork into the background.\n"); 169 printf("-v verbose (more times to increase verbosity)\n"); 170 #ifdef UB_ON_WINDOWS 171 printf("-w opt windows option: \n"); 172 printf(" install, remove - manage the services entry\n"); 173 printf(" service - used to start from services control panel\n"); 174 #endif 175 printf("Version %s\n", PACKAGE_VERSION); 176 get_event_sys(&evnm, &evsys, &evmethod); 177 printf("linked libs: %s %s (it uses %s), %s\n", 178 evnm, evsys, evmethod, 179 #ifdef HAVE_SSL 180 SSLeay_version(SSLEAY_VERSION) 181 #elif defined(HAVE_NSS) 182 NSS_GetVersion() 183 #elif defined(HAVE_NETTLE) 184 "nettle" 185 #endif 186 ); 187 printf("linked modules:"); 188 for(m = module_list_avail(); *m; m++) 189 printf(" %s", *m); 190 printf("\n"); 191 printf("BSD licensed, see LICENSE in source package for details.\n"); 192 printf("Report bugs to %s\n", PACKAGE_BUGREPORT); 193 } 194 195 #ifndef unbound_testbound 196 int replay_var_compare(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b)) 197 { 198 log_assert(0); 199 return 0; 200 } 201 #endif 202 203 /** check file descriptor count */ 204 static void 205 checkrlimits(struct config_file* cfg) 206 { 207 #ifndef S_SPLINT_S 208 #ifdef HAVE_GETRLIMIT 209 /* list has number of ports to listen to, ifs number addresses */ 210 int list = ((cfg->do_udp?1:0) + (cfg->do_tcp?1 + 211 (int)cfg->incoming_num_tcp:0)); 212 size_t listen_ifs = (size_t)(cfg->num_ifs==0? 213 ((cfg->do_ip4 && !cfg->if_automatic?1:0) + 214 (cfg->do_ip6?1:0)):cfg->num_ifs); 215 size_t listen_num = list*listen_ifs; 216 size_t outudpnum = (size_t)cfg->outgoing_num_ports; 217 size_t outtcpnum = cfg->outgoing_num_tcp; 218 size_t misc = 4; /* logfile, pidfile, stdout... */ 219 size_t perthread_noudp = listen_num + outtcpnum + 220 2/*cmdpipe*/ + 2/*libevent*/ + misc; 221 size_t perthread = perthread_noudp + outudpnum; 222 223 #if !defined(HAVE_PTHREAD) && !defined(HAVE_SOLARIS_THREADS) 224 int numthread = 1; /* it forks */ 225 #else 226 int numthread = (cfg->num_threads?cfg->num_threads:1); 227 #endif 228 size_t total = numthread * perthread + misc; 229 size_t avail; 230 struct rlimit rlim; 231 232 if(total > 1024 && 233 strncmp(event_get_version(), "mini-event", 10) == 0) { 234 log_warn("too many file descriptors requested. The builtin" 235 "mini-event cannot handle more than 1024. Config " 236 "for less fds or compile with libevent"); 237 if(numthread*perthread_noudp+15 > 1024) 238 fatal_exit("too much tcp. not enough fds."); 239 cfg->outgoing_num_ports = (int)((1024 240 - numthread*perthread_noudp 241 - 10 /* safety margin */) /numthread); 242 log_warn("continuing with less udp ports: %u", 243 cfg->outgoing_num_ports); 244 total = 1024; 245 } 246 if(perthread > 64 && 247 strncmp(event_get_version(), "winsock-event", 13) == 0) { 248 log_err("too many file descriptors requested. The winsock" 249 " event handler cannot handle more than 64 per " 250 " thread. Config for less fds"); 251 if(perthread_noudp+2 > 64) 252 fatal_exit("too much tcp. not enough fds."); 253 cfg->outgoing_num_ports = (int)((64 254 - perthread_noudp 255 - 2/* safety margin */)); 256 log_warn("continuing with less udp ports: %u", 257 cfg->outgoing_num_ports); 258 total = numthread*(perthread_noudp+ 259 (size_t)cfg->outgoing_num_ports)+misc; 260 } 261 if(getrlimit(RLIMIT_NOFILE, &rlim) < 0) { 262 log_warn("getrlimit: %s", strerror(errno)); 263 return; 264 } 265 if(rlim.rlim_cur == (rlim_t)RLIM_INFINITY) 266 return; 267 if((size_t)rlim.rlim_cur < total) { 268 avail = (size_t)rlim.rlim_cur; 269 rlim.rlim_cur = (rlim_t)(total + 10); 270 rlim.rlim_max = (rlim_t)(total + 10); 271 #ifdef HAVE_SETRLIMIT 272 if(setrlimit(RLIMIT_NOFILE, &rlim) < 0) { 273 log_warn("setrlimit: %s", strerror(errno)); 274 #endif 275 log_warn("cannot increase max open fds from %u to %u", 276 (unsigned)avail, (unsigned)total+10); 277 /* check that calculation below does not underflow, 278 * with 15 as margin */ 279 if(numthread*perthread_noudp+15 > avail) 280 fatal_exit("too much tcp. not enough fds."); 281 cfg->outgoing_num_ports = (int)((avail 282 - numthread*perthread_noudp 283 - 10 /* safety margin */) /numthread); 284 log_warn("continuing with less udp ports: %u", 285 cfg->outgoing_num_ports); 286 log_warn("increase ulimit or decrease threads, " 287 "ports in config to remove this warning"); 288 return; 289 #ifdef HAVE_SETRLIMIT 290 } 291 #endif 292 verbose(VERB_ALGO, "increased limit(open files) from %u to %u", 293 (unsigned)avail, (unsigned)total+10); 294 } 295 #else 296 (void)cfg; 297 #endif /* HAVE_GETRLIMIT */ 298 #endif /* S_SPLINT_S */ 299 } 300 301 /** set verbosity, check rlimits, cache settings */ 302 static void 303 apply_settings(struct daemon* daemon, struct config_file* cfg, 304 int cmdline_verbose, int debug_mode) 305 { 306 /* apply if they have changed */ 307 verbosity = cmdline_verbose + cfg->verbosity; 308 if (debug_mode > 1) { 309 cfg->use_syslog = 0; 310 cfg->logfile = NULL; 311 } 312 daemon_apply_cfg(daemon, cfg); 313 checkrlimits(cfg); 314 } 315 316 #ifdef HAVE_KILL 317 /** Read existing pid from pidfile. 318 * @param file: file name of pid file. 319 * @return: the pid from the file or -1 if none. 320 */ 321 static pid_t 322 readpid (const char* file) 323 { 324 int fd; 325 pid_t pid; 326 char pidbuf[32]; 327 char* t; 328 ssize_t l; 329 330 if ((fd = open(file, O_RDONLY)) == -1) { 331 if(errno != ENOENT) 332 log_err("Could not read pidfile %s: %s", 333 file, strerror(errno)); 334 return -1; 335 } 336 337 if (((l = read(fd, pidbuf, sizeof(pidbuf)))) == -1) { 338 if(errno != ENOENT) 339 log_err("Could not read pidfile %s: %s", 340 file, strerror(errno)); 341 close(fd); 342 return -1; 343 } 344 345 close(fd); 346 347 /* Empty pidfile means no pidfile... */ 348 if (l == 0) { 349 return -1; 350 } 351 352 pidbuf[sizeof(pidbuf)-1] = 0; 353 pid = (pid_t)strtol(pidbuf, &t, 10); 354 355 if (*t && *t != '\n') { 356 return -1; 357 } 358 return pid; 359 } 360 361 /** write pid to file. 362 * @param pidfile: file name of pid file. 363 * @param pid: pid to write to file. 364 */ 365 static void 366 writepid (const char* pidfile, pid_t pid) 367 { 368 FILE* f; 369 370 if ((f = fopen(pidfile, "w")) == NULL ) { 371 log_err("cannot open pidfile %s: %s", 372 pidfile, strerror(errno)); 373 return; 374 } 375 if(fprintf(f, "%lu\n", (unsigned long)pid) < 0) { 376 log_err("cannot write to pidfile %s: %s", 377 pidfile, strerror(errno)); 378 } 379 fclose(f); 380 } 381 382 /** 383 * check old pid file. 384 * @param pidfile: the file name of the pid file. 385 * @param inchroot: if pidfile is inchroot and we can thus expect to 386 * be able to delete it. 387 */ 388 static void 389 checkoldpid(char* pidfile, int inchroot) 390 { 391 pid_t old; 392 if((old = readpid(pidfile)) != -1) { 393 /* see if it is still alive */ 394 if(kill(old, 0) == 0 || errno == EPERM) 395 log_warn("unbound is already running as pid %u.", 396 (unsigned)old); 397 else if(inchroot) 398 log_warn("did not exit gracefully last time (%u)", 399 (unsigned)old); 400 } 401 } 402 #endif /* HAVE_KILL */ 403 404 /** detach from command line */ 405 static void 406 detach(void) 407 { 408 #if defined(HAVE_DAEMON) && !defined(DEPRECATED_DAEMON) 409 /* use POSIX daemon(3) function */ 410 if(daemon(1, 0) != 0) 411 fatal_exit("daemon failed: %s", strerror(errno)); 412 #else /* no HAVE_DAEMON */ 413 #ifdef HAVE_FORK 414 int fd; 415 /* Take off... */ 416 switch (fork()) { 417 case 0: 418 break; 419 case -1: 420 fatal_exit("fork failed: %s", strerror(errno)); 421 default: 422 /* exit interactive session */ 423 exit(0); 424 } 425 /* detach */ 426 #ifdef HAVE_SETSID 427 if(setsid() == -1) 428 fatal_exit("setsid() failed: %s", strerror(errno)); 429 #endif 430 if ((fd = open("/dev/null", O_RDWR, 0)) != -1) { 431 (void)dup2(fd, STDIN_FILENO); 432 (void)dup2(fd, STDOUT_FILENO); 433 (void)dup2(fd, STDERR_FILENO); 434 if (fd > 2) 435 (void)close(fd); 436 } 437 #endif /* HAVE_FORK */ 438 #endif /* HAVE_DAEMON */ 439 } 440 441 /** daemonize, drop user priviliges and chroot if needed */ 442 static void 443 perform_setup(struct daemon* daemon, struct config_file* cfg, int debug_mode, 444 const char** cfgfile) 445 { 446 #ifdef HAVE_KILL 447 int pidinchroot; 448 #endif 449 #ifdef HAVE_GETPWNAM 450 struct passwd *pwd = NULL; 451 452 if(cfg->username && cfg->username[0]) { 453 if((pwd = getpwnam(cfg->username)) == NULL) 454 fatal_exit("user '%s' does not exist.", cfg->username); 455 /* endpwent below, in case we need pwd for setusercontext */ 456 } 457 #endif 458 #ifdef UB_ON_WINDOWS 459 w_config_adjust_directory(cfg); 460 #endif 461 462 /* init syslog (as root) if needed, before daemonize, otherwise 463 * a fork error could not be printed since daemonize closed stderr.*/ 464 if(cfg->use_syslog) { 465 log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir); 466 } 467 /* if using a logfile, we cannot open it because the logfile would 468 * be created with the wrong permissions, we cannot chown it because 469 * we cannot chown system logfiles, so we do not open at all. 470 * So, using a logfile, the user does not see errors unless -d is 471 * given to unbound on the commandline. */ 472 473 /* read ssl keys while superuser and outside chroot */ 474 #ifdef HAVE_SSL 475 if(!(daemon->rc = daemon_remote_create(cfg))) 476 fatal_exit("could not set up remote-control"); 477 if(cfg->ssl_service_key && cfg->ssl_service_key[0]) { 478 if(!(daemon->listen_sslctx = listen_sslctx_create( 479 cfg->ssl_service_key, cfg->ssl_service_pem, NULL))) 480 fatal_exit("could not set up listen SSL_CTX"); 481 } 482 if(!(daemon->connect_sslctx = connect_sslctx_create(NULL, NULL, NULL))) 483 fatal_exit("could not set up connect SSL_CTX"); 484 #endif 485 486 #ifdef HAVE_KILL 487 /* true if pidfile is inside chrootdir, or nochroot */ 488 pidinchroot = !(cfg->chrootdir && cfg->chrootdir[0]) || 489 (cfg->chrootdir && cfg->chrootdir[0] && 490 strncmp(cfg->pidfile, cfg->chrootdir, 491 strlen(cfg->chrootdir))==0); 492 493 /* check old pid file before forking */ 494 if(cfg->pidfile && cfg->pidfile[0]) { 495 /* calculate position of pidfile */ 496 if(cfg->pidfile[0] == '/') 497 daemon->pidfile = strdup(cfg->pidfile); 498 else daemon->pidfile = fname_after_chroot(cfg->pidfile, 499 cfg, 1); 500 if(!daemon->pidfile) 501 fatal_exit("pidfile alloc: out of memory"); 502 checkoldpid(daemon->pidfile, pidinchroot); 503 } 504 #endif 505 506 /* daemonize because pid is needed by the writepid func */ 507 if(!debug_mode && cfg->do_daemonize) { 508 detach(); 509 } 510 511 /* write new pidfile (while still root, so can be outside chroot) */ 512 #ifdef HAVE_KILL 513 if(cfg->pidfile && cfg->pidfile[0]) { 514 writepid(daemon->pidfile, getpid()); 515 if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1 && 516 pidinchroot) { 517 # ifdef HAVE_CHOWN 518 if(chown(daemon->pidfile, cfg_uid, cfg_gid) == -1) { 519 verbose(VERB_QUERY, "cannot chown %u.%u %s: %s", 520 (unsigned)cfg_uid, (unsigned)cfg_gid, 521 daemon->pidfile, strerror(errno)); 522 } 523 # endif /* HAVE_CHOWN */ 524 } 525 } 526 #else 527 (void)daemon; 528 #endif /* HAVE_KILL */ 529 530 /* Set user context */ 531 #ifdef HAVE_GETPWNAM 532 if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) { 533 #ifdef HAVE_SETUSERCONTEXT 534 /* setusercontext does initgroups, setuid, setgid, and 535 * also resource limits from login config, but we 536 * still call setresuid, setresgid to be sure to set all uid*/ 537 if(setusercontext(NULL, pwd, cfg_uid, (unsigned) 538 LOGIN_SETALL & ~LOGIN_SETUSER & ~LOGIN_SETGROUP) != 0) 539 log_warn("unable to setusercontext %s: %s", 540 cfg->username, strerror(errno)); 541 #endif /* HAVE_SETUSERCONTEXT */ 542 } 543 #endif /* HAVE_GETPWNAM */ 544 545 /* box into the chroot */ 546 #ifdef HAVE_CHROOT 547 if(cfg->chrootdir && cfg->chrootdir[0]) { 548 if(chdir(cfg->chrootdir)) { 549 fatal_exit("unable to chdir to chroot %s: %s", 550 cfg->chrootdir, strerror(errno)); 551 } 552 verbose(VERB_QUERY, "chdir to %s", cfg->chrootdir); 553 if(chroot(cfg->chrootdir)) 554 fatal_exit("unable to chroot to %s: %s", 555 cfg->chrootdir, strerror(errno)); 556 if(chdir("/")) 557 fatal_exit("unable to chdir to / in chroot %s: %s", 558 cfg->chrootdir, strerror(errno)); 559 verbose(VERB_QUERY, "chroot to %s", cfg->chrootdir); 560 if(strncmp(*cfgfile, cfg->chrootdir, 561 strlen(cfg->chrootdir)) == 0) 562 (*cfgfile) += strlen(cfg->chrootdir); 563 564 /* adjust stored pidfile for chroot */ 565 if(daemon->pidfile && daemon->pidfile[0] && 566 strncmp(daemon->pidfile, cfg->chrootdir, 567 strlen(cfg->chrootdir))==0) { 568 char* old = daemon->pidfile; 569 daemon->pidfile = strdup(old+strlen(cfg->chrootdir)); 570 free(old); 571 if(!daemon->pidfile) 572 log_err("out of memory in pidfile adjust"); 573 } 574 daemon->chroot = strdup(cfg->chrootdir); 575 if(!daemon->chroot) 576 log_err("out of memory in daemon chroot dir storage"); 577 } 578 #else 579 (void)cfgfile; 580 #endif 581 /* change to working directory inside chroot */ 582 if(cfg->directory && cfg->directory[0]) { 583 char* dir = cfg->directory; 584 if(cfg->chrootdir && cfg->chrootdir[0] && 585 strncmp(dir, cfg->chrootdir, 586 strlen(cfg->chrootdir)) == 0) 587 dir += strlen(cfg->chrootdir); 588 if(dir[0]) { 589 if(chdir(dir)) { 590 fatal_exit("Could not chdir to %s: %s", 591 dir, strerror(errno)); 592 } 593 verbose(VERB_QUERY, "chdir to %s", dir); 594 } 595 } 596 597 /* drop permissions after chroot, getpwnam, pidfile, syslog done*/ 598 #ifdef HAVE_GETPWNAM 599 if(cfg->username && cfg->username[0] && cfg_uid != (uid_t)-1) { 600 # ifdef HAVE_INITGROUPS 601 if(initgroups(cfg->username, cfg_gid) != 0) 602 log_warn("unable to initgroups %s: %s", 603 cfg->username, strerror(errno)); 604 # endif /* HAVE_INITGROUPS */ 605 endpwent(); 606 607 #ifdef HAVE_SETRESGID 608 if(setresgid(cfg_gid,cfg_gid,cfg_gid) != 0) 609 #elif defined(HAVE_SETREGID) && !defined(DARWIN_BROKEN_SETREUID) 610 if(setregid(cfg_gid,cfg_gid) != 0) 611 #else /* use setgid */ 612 if(setgid(cfg_gid) != 0) 613 #endif /* HAVE_SETRESGID */ 614 fatal_exit("unable to set group id of %s: %s", 615 cfg->username, strerror(errno)); 616 #ifdef HAVE_SETRESUID 617 if(setresuid(cfg_uid,cfg_uid,cfg_uid) != 0) 618 #elif defined(HAVE_SETREUID) && !defined(DARWIN_BROKEN_SETREUID) 619 if(setreuid(cfg_uid,cfg_uid) != 0) 620 #else /* use setuid */ 621 if(setuid(cfg_uid) != 0) 622 #endif /* HAVE_SETRESUID */ 623 fatal_exit("unable to set user id of %s: %s", 624 cfg->username, strerror(errno)); 625 verbose(VERB_QUERY, "drop user privileges, run as %s", 626 cfg->username); 627 } 628 #endif /* HAVE_GETPWNAM */ 629 /* file logging inited after chroot,chdir,setuid is done so that 630 * it would succeed on SIGHUP as well */ 631 if(!cfg->use_syslog) 632 log_init(cfg->logfile, cfg->use_syslog, cfg->chrootdir); 633 } 634 635 /** 636 * Run the daemon. 637 * @param cfgfile: the config file name. 638 * @param cmdline_verbose: verbosity resulting from commandline -v. 639 * These increase verbosity as specified in the config file. 640 * @param debug_mode: if set, do not daemonize. 641 */ 642 static void 643 run_daemon(const char* cfgfile, int cmdline_verbose, int debug_mode) 644 { 645 struct config_file* cfg = NULL; 646 struct daemon* daemon = NULL; 647 int done_setup = 0; 648 649 if(!(daemon = daemon_init())) 650 fatal_exit("alloc failure"); 651 while(!daemon->need_to_exit) { 652 if(done_setup) 653 verbose(VERB_OPS, "Restart of %s.", PACKAGE_STRING); 654 else verbose(VERB_OPS, "Start of %s.", PACKAGE_STRING); 655 656 /* config stuff */ 657 if(!(cfg = config_create())) 658 fatal_exit("Could not alloc config defaults"); 659 if(!config_read(cfg, cfgfile, daemon->chroot)) { 660 if(errno != ENOENT) 661 fatal_exit("Could not read config file: %s", 662 cfgfile); 663 log_warn("Continuing with default config settings"); 664 } 665 apply_settings(daemon, cfg, cmdline_verbose, debug_mode); 666 if(!done_setup) 667 config_lookup_uid(cfg); 668 669 /* prepare */ 670 if(!daemon_open_shared_ports(daemon)) 671 fatal_exit("could not open ports"); 672 if(!done_setup) { 673 perform_setup(daemon, cfg, debug_mode, &cfgfile); 674 done_setup = 1; 675 } else { 676 /* reopen log after HUP to facilitate log rotation */ 677 if(!cfg->use_syslog) 678 log_init(cfg->logfile, 0, cfg->chrootdir); 679 } 680 /* work */ 681 daemon_fork(daemon); 682 683 /* clean up for restart */ 684 verbose(VERB_ALGO, "cleanup."); 685 daemon_cleanup(daemon); 686 config_delete(cfg); 687 } 688 verbose(VERB_ALGO, "Exit cleanup."); 689 /* this unlink may not work if the pidfile is located outside 690 * of the chroot/workdir or we no longer have permissions */ 691 if(daemon->pidfile) { 692 int fd; 693 /* truncate pidfile */ 694 fd = open(daemon->pidfile, O_WRONLY | O_TRUNC, 0644); 695 if(fd != -1) 696 close(fd); 697 /* delete pidfile */ 698 unlink(daemon->pidfile); 699 } 700 daemon_delete(daemon); 701 } 702 703 /** getopt global, in case header files fail to declare it. */ 704 extern int optind; 705 /** getopt global, in case header files fail to declare it. */ 706 extern char* optarg; 707 708 /** 709 * main program. Set options given commandline arguments. 710 * @param argc: number of commandline arguments. 711 * @param argv: array of commandline arguments. 712 * @return: exit status of the program. 713 */ 714 int 715 main(int argc, char* argv[]) 716 { 717 int c; 718 const char* cfgfile = CONFIGFILE; 719 const char* winopt = NULL; 720 int cmdline_verbose = 0; 721 int debug_mode = 0; 722 #ifdef UB_ON_WINDOWS 723 int cmdline_cfg = 0; 724 #endif 725 726 #ifdef HAVE_SBRK 727 /* take debug snapshot of heap */ 728 unbound_start_brk = sbrk(0); 729 #endif 730 731 log_init(NULL, 0, NULL); 732 log_ident_set(strrchr(argv[0],'/')?strrchr(argv[0],'/')+1:argv[0]); 733 /* parse the options */ 734 while( (c=getopt(argc, argv, "c:dhvw:")) != -1) { 735 switch(c) { 736 case 'c': 737 cfgfile = optarg; 738 #ifdef UB_ON_WINDOWS 739 cmdline_cfg = 1; 740 #endif 741 break; 742 case 'v': 743 cmdline_verbose++; 744 verbosity++; 745 break; 746 case 'd': 747 debug_mode++; 748 break; 749 case 'w': 750 winopt = optarg; 751 break; 752 case '?': 753 case 'h': 754 default: 755 usage(); 756 return 1; 757 } 758 } 759 argc -= optind; 760 argv += optind; 761 762 if(winopt) { 763 #ifdef UB_ON_WINDOWS 764 wsvc_command_option(winopt, cfgfile, cmdline_verbose, 765 cmdline_cfg); 766 #else 767 fatal_exit("option not supported"); 768 #endif 769 } 770 771 if(argc != 0) { 772 usage(); 773 return 1; 774 } 775 776 run_daemon(cfgfile, cmdline_verbose, debug_mode); 777 log_init(NULL, 0, NULL); /* close logfile */ 778 return 0; 779 } 780