contrib/ntp/ntpd/ntpd.c

   1 /*
   2  * ntpd.c - main program for the fixed point NTP daemon
   3  */
   4
   5 #ifdef HAVE_CONFIG_H
   6 # include <config.h>
   7 #endif
   8
   9 #include "ntp_machine.h"
  10 #include "ntpd.h"
  11 #include "ntp_io.h"
  12 #include "ntp_stdlib.h"
  13 #include <ntp_random.h>
  14
  15 #include "ntp_config.h"
  16 #include "ntp_syslog.h"
  17 #include "ntp_assert.h"
  18 #include "isc/error.h"
  19 #include "isc/strerror.h"
  20 #include "isc/formatcheck.h"
  21 #include "iosignal.h"
  22
  23 #ifdef SIM
  24 # include "ntpsim.h"
  25 #endif
  26
  27 #include "ntp_libopts.h"
  28 #include "ntpd-opts.h"
  29
  30 /* there's a short treatise below what the thread stuff is for.
  31  * [Bug 2954] enable the threading warm-up only for Linux.
  32  */
  33 #if defined(HAVE_PTHREADS) && HAVE_PTHREADS && !defined(NO_THREADS)
  34 # ifdef HAVE_PTHREAD_H
  35 #  include <pthread.h>
  36 # endif
  37 # if defined(linux)
  38 #  define NEED_PTHREAD_WARMUP
  39 # endif
  40 #endif
  41
  42 #ifdef HAVE_UNISTD_H
  43 # include <unistd.h>
  44 #endif
  45 #ifdef HAVE_SYS_STAT_H
  46 # include <sys/stat.h>
  47 #endif
  48 #include <stdio.h>
  49 #ifdef HAVE_SYS_PARAM_H
  50 # include <sys/param.h>
  51 #endif
  52 #ifdef HAVE_SYS_SIGNAL_H
  53 # include <sys/signal.h>
  54 #else
  55 # include <signal.h>
  56 #endif
  57 #ifdef HAVE_SYS_IOCTL_H
  58 # include <sys/ioctl.h>
  59 #endif /* HAVE_SYS_IOCTL_H */
  60 #if defined(HAVE_RTPRIO)
  61 # ifdef HAVE_SYS_LOCK_H
  62 #  include <sys/lock.h>
  63 # endif
  64 # include <sys/rtprio.h>
  65 #else
  66 # ifdef HAVE_PLOCK
  67 #  ifdef HAVE_SYS_LOCK_H
  68 #       include <sys/lock.h>
  69 #  endif
  70 # endif
  71 #endif
  72 #if defined(HAVE_SCHED_SETSCHEDULER)
  73 # ifdef HAVE_SCHED_H
  74 #  include <sched.h>
  75 # else
  76 #  ifdef HAVE_SYS_SCHED_H
  77 #   include <sys/sched.h>
  78 #  endif
  79 # endif
  80 #endif
  81 #if defined(HAVE_SYS_MMAN_H)
  82 # include <sys/mman.h>
  83 #endif
  84
  85 #ifdef HAVE_TERMIOS_H
  86 # include <termios.h>
  87 #endif
  88
  89 #ifdef SYS_DOMAINOS
  90 # include <apollo/base.h>
  91 #endif /* SYS_DOMAINOS */
  92
  93
  94 #include "recvbuff.h"
  95 #include "ntp_cmdargs.h"
  96
  97 #if 0                           /* HMS: I don't think we need this. 961223 */
  98 #ifdef LOCK_PROCESS
  99 # ifdef SYS_SOLARIS
 100 #  include <sys/mman.h>
 101 # else
 102 #  include <sys/lock.h>
 103 # endif
 104 #endif
 105 #endif
 106
 107 #ifdef SYS_WINNT
 108 # include "ntservice.h"
 109 #endif
 110
 111 #ifdef _AIX
 112 # include <ulimit.h>
 113 #endif /* _AIX */
 114
 115 #ifdef SCO5_CLOCK
 116 # include <sys/ci/ciioctl.h>
 117 #endif
 118
 119 #ifdef HAVE_DROPROOT
 120 # include <ctype.h>
 121 # include <grp.h>
 122 # include <pwd.h>
 123 #ifdef HAVE_LINUX_CAPABILITIES
 124 # include <sys/capability.h>
 125 # include <sys/prctl.h>
 126 #endif /* HAVE_LINUX_CAPABILITIES */
 127 #if defined(HAVE_PRIV_H) && defined(HAVE_SOLARIS_PRIVS)
 128 # include <priv.h>
 129 #endif /* HAVE_PRIV_H */
 130 #endif /* HAVE_DROPROOT */
 131
 132 #if defined (LIBSECCOMP) && (KERN_SECCOMP)
 133 /* # include <sys/types.h> */
 134 # include <sys/resource.h>
 135 # include <seccomp.h>
 136 #endif /* LIBSECCOMP and KERN_SECCOMP */
 137
 138 #ifdef HAVE_DNSREGISTRATION
 139 # include <dns_sd.h>
 140 DNSServiceRef mdns;
 141 #endif
 142
 143 #ifdef HAVE_SETPGRP_0
 144 # define ntp_setpgrp(x, y)      setpgrp()
 145 #else
 146 # define ntp_setpgrp(x, y)      setpgrp(x, y)
 147 #endif
 148
 149 #ifdef HAVE_SOLARIS_PRIVS
 150 # define LOWPRIVS "basic,sys_time,net_privaddr,proc_setid,!proc_info,!proc_session,!proc_exec"
 151 static priv_set_t *lowprivs = NULL;
 152 static priv_set_t *highprivs = NULL;
 153 #endif /* HAVE_SOLARIS_PRIVS */
 154 /*
 155  * Scheduling priority we run at
 156  */
 157 #define NTPD_PRIO       (-12)
 158
 159 int priority_done = 2;          /* 0 - Set priority */
 160                                 /* 1 - priority is OK where it is */
 161                                 /* 2 - Don't set priority */
 162                                 /* 1 and 2 are pretty much the same */
 163
 164 int listen_to_virtual_ips = TRUE;
 165
 166 /*
 167  * No-fork flag.  If set, we do not become a background daemon.
 168  */
 169 int nofork;                     /* Fork by default */
 170
 171 #ifdef HAVE_DNSREGISTRATION
 172 /*
 173  * mDNS registration flag. If set, we attempt to register with the mDNS system, but only
 174  * after we have synched the first time. If the attempt fails, then try again once per
 175  * minute for up to 5 times. After all, we may be starting before mDNS.
 176  */
 177 int mdnsreg = FALSE;
 178 int mdnstries = 5;
 179 #endif  /* HAVE_DNSREGISTRATION */
 180
 181 #ifdef HAVE_DROPROOT
 182 int droproot;
 183 int root_dropped;
 184 char *user;             /* User to switch to */
 185 char *group;            /* group to switch to */
 186 const char *chrootdir;  /* directory to chroot to */
 187 uid_t sw_uid;
 188 gid_t sw_gid;
 189 struct group *gr;
 190 struct passwd *pw;
 191 #endif /* HAVE_DROPROOT */
 192
 193 #ifdef HAVE_WORKING_FORK
 194 int     waitsync_fd_to_close = -1;      /* -w/--wait-sync */
 195 #endif
 196
 197 /*
 198  * Version declaration
 199  */
 200 extern const char *Version;
 201
 202 char const *progname;
 203
 204 int was_alarmed;
 205
 206 #ifdef DECL_SYSCALL
 207 /*
 208  * We put this here, since the argument profile is syscall-specific
 209  */
 210 extern int syscall      (int, ...);
 211 #endif /* DECL_SYSCALL */
 212
 213
 214 #if !defined(SIM) && defined(SIGDIE1)
 215 static volatile int signalled   = 0;
 216 static volatile int signo       = 0;
 217
 218 /* In an ideal world, 'finish_safe()' would declared as noreturn... */
 219 static  void            finish_safe     (int);
 220 static  RETSIGTYPE      finish          (int);
 221 #endif
 222
 223 #if !defined(SIM) && defined(HAVE_WORKING_FORK)
 224 static int      wait_child_sync_if      (int, long);
 225 #endif
 226
 227 #if !defined(SIM) && !defined(SYS_WINNT)
 228 # ifdef DEBUG
 229 static  RETSIGTYPE      moredebug       (int);
 230 static  RETSIGTYPE      lessdebug       (int);
 231 # else  /* !DEBUG follows */
 232 static  RETSIGTYPE      no_debug        (int);
 233 # endif /* !DEBUG */
 234 #endif  /* !SIM && !SYS_WINNT */
 235
 236 #ifndef WORK_FORK
 237 int     saved_argc;
 238 char ** saved_argv;
 239 #endif
 240
 241 #ifndef SIM
 242 int             ntpdmain                (int, char **);
 243 static void     set_process_priority    (void);
 244 static void     assertion_failed        (const char *, int,
 245                                          isc_assertiontype_t,
 246                                          const char *)
 247                         __attribute__   ((__noreturn__));
 248 static void     library_fatal_error     (const char *, int,
 249                                          const char *, va_list)
 250                                         ISC_FORMAT_PRINTF(3, 0);
 251 static void     library_unexpected_error(const char *, int,
 252                                          const char *, va_list)
 253                                         ISC_FORMAT_PRINTF(3, 0);
 254 #endif  /* !SIM */
 255
 256
 257 /* Bug2332 unearthed a problem in the interaction of reduced user
 258  * privileges, the limits on memory usage and some versions of the
 259  * pthread library on Linux systems. The 'pthread_cancel()' function and
 260  * likely some others need to track the stack of the thread involved,
 261  * and uses a function that comes from GCC (--> libgcc_s.so) to do
 262  * this. Unfortunately the developers of glibc decided to load the
 263  * library on demand, which speeds up program start but can cause
 264  * trouble here: Due to all the things NTPD does to limit its resource
 265  * usage, this deferred load of libgcc_s does not always work once the
 266  * restrictions are in effect.
 267  *
 268  * One way out of this was attempting a forced link against libgcc_s
 269  * when possible because it makes the library available immediately
 270  * without deferred load. (The symbol resolution would still be dynamic
 271  * and on demand, but the code would already be in the process image.)
 272  *
 273  * This is a tricky thing to do, since it's not necessary everywhere,
 274  * not possible everywhere, has shown to break the build of other
 275  * programs in the NTP suite and is now generally frowned upon.
 276  *
 277  * So we take a different approach here: We creat a worker thread that does
 278  * actually nothing except waiting for cancellation and cancel it. If
 279  * this is done before all the limitations are put in place, the
 280  * machinery is pre-heated and all the runtime stuff should be in place
 281  * and useable when needed.
 282  *
 283  * This uses only the standard pthread API and should work with all
 284  * implementations of pthreads. It is not necessary everywhere, but it's
 285  * cheap enough to go on nearly unnoticed.
 286  *
 287  * Addendum: Bug 2954 showed that the assumption that this should work
 288  * with all OS is wrong -- at least FreeBSD bombs heavily.
 289  */
 290 #ifdef NEED_PTHREAD_WARMUP
 291
 292 /* simple thread function: sleep until cancelled, just to exercise
 293  * thread cancellation.
 294  */
 295 static void*
 296 my_pthread_warmup_worker(
 297         void *thread_args)
 298 {
 299         (void)thread_args;
 300         for (;;)
 301                 sleep(10);
 302         return NULL;
 303 }
 304
 305 /* pre-heat threading: create a thread and cancel it, just to exercise
 306  * thread cancellation.
 307  */
 308 static void
 309 my_pthread_warmup(void)
 310 {
 311         pthread_t       thread;
 312         pthread_attr_t  thr_attr;
 313         int             rc;
 314
 315         pthread_attr_init(&thr_attr);
 316 #if defined(HAVE_PTHREAD_ATTR_GETSTACKSIZE) && \
 317     defined(HAVE_PTHREAD_ATTR_SETSTACKSIZE) && \
 318     defined(PTHREAD_STACK_MIN)
 319         {
 320                 size_t ssmin = 32*1024; /* 32kB should be minimum */
 321                 if (ssmin < PTHREAD_STACK_MIN)
 322                         ssmin = PTHREAD_STACK_MIN;
 323                 rc = pthread_attr_setstacksize(&thr_attr, ssmin);
 324                 if (0 != rc)
 325                         msyslog(LOG_ERR,
 326                                 "my_pthread_warmup: pthread_attr_setstacksize() -> %s",
 327                                 strerror(rc));
 328         }
 329 #endif
 330         rc = pthread_create(
 331                 &thread, &thr_attr, my_pthread_warmup_worker, NULL);
 332         pthread_attr_destroy(&thr_attr);
 333         if (0 != rc) {
 334                 msyslog(LOG_ERR,
 335                         "my_pthread_warmup: pthread_create() -> %s",
 336                         strerror(rc));
 337         } else {
 338                 pthread_cancel(thread);
 339                 pthread_join(thread, NULL);
 340         }
 341 }
 342
 343 #endif /*defined(NEED_PTHREAD_WARMUP)*/
 344
 345 #ifdef NEED_EARLY_FORK
 346 static void
 347 dummy_callback(void) { return; }
 348
 349 static void
 350 fork_nonchroot_worker(void) {
 351         getaddrinfo_sometime("localhost", "ntp", NULL, INITIAL_DNS_RETRY,
 352                              (gai_sometime_callback)&dummy_callback, NULL);
 353 }
 354 #endif /* NEED_EARLY_FORK */
 355
 356 void
 357 parse_cmdline_opts(
 358         int *   pargc,
 359         char ***pargv
 360         )
 361 {
 362         static int      parsed;
 363         static int      optct;
 364
 365         if (!parsed)
 366                 optct = ntpOptionProcess(&ntpdOptions, *pargc, *pargv);
 367
 368         parsed = 1;
 369
 370         *pargc -= optct;
 371         *pargv += optct;
 372 }
 373
 374
 375 #ifdef SIM
 376 int
 377 main(
 378         int argc,
 379         char *argv[]
 380         )
 381 {
 382         progname = argv[0];
 383         parse_cmdline_opts(&argc, &argv);
 384 #ifdef DEBUG
 385         debug = OPT_VALUE_SET_DEBUG_LEVEL;
 386         DPRINTF(1, ("%s\n", Version));
 387 #endif
 388
 389         return ntpsim(argc, argv);
 390 }
 391 #else   /* !SIM follows */
 392 #ifdef NO_MAIN_ALLOWED
 393 CALL(ntpd,"ntpd",ntpdmain);
 394 #else   /* !NO_MAIN_ALLOWED follows */
 395 #ifndef SYS_WINNT
 396 int
 397 main(
 398         int argc,
 399         char *argv[]
 400         )
 401 {
 402         return ntpdmain(argc, argv);
 403 }
 404 #endif /* !SYS_WINNT */
 405 #endif /* !NO_MAIN_ALLOWED */
 406 #endif /* !SIM */
 407
 408 #ifdef _AIX
 409 /*
 410  * OK. AIX is different than solaris in how it implements plock().
 411  * If you do NOT adjust the stack limit, you will get the MAXIMUM
 412  * stack size allocated and PINNED with you program. To check the
 413  * value, use ulimit -a.
 414  *
 415  * To fix this, we create an automatic variable and set our stack limit
 416  * to that PLUS 32KB of extra space (we need some headroom).
 417  *
 418  * This subroutine gets the stack address.
 419  *
 420  * Grover Davidson and Matt Ladendorf
 421  *
 422  */
 423 static char *
 424 get_aix_stack(void)
 425 {
 426         char ch;
 427         return (&ch);
 428 }
 429
 430 /*
 431  * Signal handler for SIGDANGER.
 432  */
 433 static void
 434 catch_danger(int signo)
 435 {
 436         msyslog(LOG_INFO, "ntpd: setpgid(): %m");
 437         /* Make the system believe we'll free something, but don't do it! */
 438         return;
 439 }
 440 #endif /* _AIX */
 441
 442 /*
 443  * Set the process priority
 444  */
 445 #ifndef SIM
 446 static void
 447 set_process_priority(void)
 448 {
 449
 450 # ifdef DEBUG
 451         if (debug > 1)
 452                 msyslog(LOG_DEBUG, "set_process_priority: %s: priority_done is <%d>",
 453                         ((priority_done)
 454                          ? "Leave priority alone"
 455                          : "Attempt to set priority"
 456                                 ),
 457                         priority_done);
 458 # endif /* DEBUG */
 459
 460 # if defined(HAVE_SCHED_SETSCHEDULER)
 461         if (!priority_done) {
 462                 extern int config_priority_override, config_priority;
 463                 int pmax, pmin;
 464                 struct sched_param sched;
 465
 466                 pmax = sched_get_priority_max(SCHED_FIFO);
 467                 sched.sched_priority = pmax;
 468                 if ( config_priority_override ) {
 469                         pmin = sched_get_priority_min(SCHED_FIFO);
 470                         if ( config_priority > pmax )
 471                                 sched.sched_priority = pmax;
 472                         else if ( config_priority < pmin )
 473                                 sched.sched_priority = pmin;
 474                         else
 475                                 sched.sched_priority = config_priority;
 476                 }
 477                 if ( sched_setscheduler(0, SCHED_FIFO, &sched) == -1 )
 478                         msyslog(LOG_ERR, "sched_setscheduler(): %m");
 479                 else
 480                         ++priority_done;
 481         }
 482 # endif /* HAVE_SCHED_SETSCHEDULER */
 483 # ifdef HAVE_RTPRIO
 484 #  ifdef RTP_SET
 485         if (!priority_done) {
 486                 struct rtprio srtp;
 487
 488                 srtp.type = RTP_PRIO_REALTIME;  /* was: RTP_PRIO_NORMAL */
 489                 srtp.prio = 0;          /* 0 (hi) -> RTP_PRIO_MAX (31,lo) */
 490
 491                 if (rtprio(RTP_SET, getpid(), &srtp) < 0)
 492                         msyslog(LOG_ERR, "rtprio() error: %m");
 493                 else
 494                         ++priority_done;
 495         }
 496 #  else /* !RTP_SET follows */
 497         if (!priority_done) {
 498                 if (rtprio(0, 120) < 0)
 499                         msyslog(LOG_ERR, "rtprio() error: %m");
 500                 else
 501                         ++priority_done;
 502         }
 503 #  endif        /* !RTP_SET */
 504 # endif /* HAVE_RTPRIO */
 505 # if defined(NTPD_PRIO) && NTPD_PRIO != 0
 506 #  ifdef HAVE_ATT_NICE
 507         if (!priority_done) {
 508                 errno = 0;
 509                 if (-1 == nice (NTPD_PRIO) && errno != 0)
 510                         msyslog(LOG_ERR, "nice() error: %m");
 511                 else
 512                         ++priority_done;
 513         }
 514 #  endif        /* HAVE_ATT_NICE */
 515 #  ifdef HAVE_BSD_NICE
 516         if (!priority_done) {
 517                 if (-1 == setpriority(PRIO_PROCESS, 0, NTPD_PRIO))
 518                         msyslog(LOG_ERR, "setpriority() error: %m");
 519                 else
 520                         ++priority_done;
 521         }
 522 #  endif        /* HAVE_BSD_NICE */
 523 # endif /* NTPD_PRIO && NTPD_PRIO != 0 */
 524         if (!priority_done)
 525                 msyslog(LOG_ERR, "set_process_priority: No way found to improve our priority");
 526 }
 527 #endif  /* !SIM */
 528
 529 #if !defined(SIM) && !defined(SYS_WINNT)
 530 /*
 531  * Detach from terminal (much like daemon())
 532  * Nothe that this function calls exit()
 533  */
 534 # ifdef HAVE_WORKING_FORK
 535 static void
 536 detach_from_terminal(
 537         int pipe_fds[2],
 538         long wait_sync,
 539         const char *logfilename
 540         )
 541 {
 542         int rc;
 543         int exit_code;
 544 #  if !defined(HAVE_SETSID) && !defined (HAVE_SETPGID) && defined(TIOCNOTTY)
 545         int             fid;
 546 #  endif
 547 #  ifdef _AIX
 548         struct sigaction sa;
 549 #  endif
 550
 551         rc = fork();
 552         if (-1 == rc) {
 553                 exit_code = (errno) ? errno : -1;
 554                 msyslog(LOG_ERR, "fork: %m");
 555                 exit(exit_code);
 556         }
 557         if (rc > 0) {
 558                 /* parent */
 559                 exit_code = wait_child_sync_if(pipe_fds[0],
 560                                                wait_sync);
 561                 exit(exit_code);
 562         }
 563
 564         /*
 565          * child/daemon
 566          * close all open files excepting waitsync_fd_to_close.
 567          * msyslog() unreliable until after init_logging().
 568          */
 569         closelog();
 570         if (syslog_file != NULL) {
 571                 fclose(syslog_file);
 572                 syslog_file = NULL;
 573                 syslogit = TRUE;
 574         }
 575         close_all_except(waitsync_fd_to_close);
 576         INSIST(0 == open("/dev/null", 0) && 1 == dup2(0, 1) \
 577                 && 2 == dup2(0, 2));
 578
 579         init_logging(progname, 0, TRUE);
 580         /* we lost our logfile (if any) daemonizing */
 581         setup_logfile(logfilename);
 582
 583 #  ifdef SYS_DOMAINOS
 584         {
 585                 uid_$t puid;
 586                 status_$t st;
 587
 588                 proc2_$who_am_i(&puid);
 589                 proc2_$make_server(&puid, &st);
 590         }
 591 #  endif        /* SYS_DOMAINOS */
 592 #  ifdef HAVE_SETSID
 593         if (setsid() == (pid_t)-1)
 594                 msyslog(LOG_ERR, "setsid(): %m");
 595 #  elif defined(HAVE_SETPGID)
 596         if (setpgid(0, 0) == -1)
 597                 msyslog(LOG_ERR, "setpgid(): %m");
 598 #  else         /* !HAVE_SETSID && !HAVE_SETPGID follows */
 599 #   ifdef TIOCNOTTY
 600         fid = open("/dev/tty", 2);
 601         if (fid >= 0) {
 602                 ioctl(fid, (u_long)TIOCNOTTY, NULL);
 603                 close(fid);
 604         }
 605 #   endif       /* TIOCNOTTY */
 606         ntp_setpgrp(0, getpid());
 607 #  endif        /* !HAVE_SETSID && !HAVE_SETPGID */
 608 #  ifdef _AIX
 609         /* Don't get killed by low-on-memory signal. */
 610         sa.sa_handler = catch_danger;
 611         sigemptyset(&sa.sa_mask);
 612         sa.sa_flags = SA_RESTART;
 613         sigaction(SIGDANGER, &sa, NULL);
 614 #  endif        /* _AIX */
 615
 616         return;
 617 }
 618 # endif /* HAVE_WORKING_FORK */
 619
 620 #ifdef HAVE_DROPROOT
 621 /*
 622  * Map user name/number to user ID
 623 */
 624 static int
 625 map_user(
 626         )
 627 {
 628         char *endp;
 629
 630         if (isdigit((unsigned char)*user)) {
 631                 sw_uid = (uid_t)strtoul(user, &endp, 0);
 632                 if (*endp != '\0')
 633                         goto getuser;
 634
 635                 if ((pw = getpwuid(sw_uid)) != NULL) {
 636                         free(user);
 637                         user = estrdup(pw->pw_name);
 638                         sw_gid = pw->pw_gid;
 639                 } else {
 640                         errno = 0;
 641                         msyslog(LOG_ERR, "Cannot find user ID %s", user);
 642                         return 0;
 643                 }
 644
 645         } else {
 646 getuser:
 647                 errno = 0;
 648                 if ((pw = getpwnam(user)) != NULL) {
 649                         sw_uid = pw->pw_uid;
 650                         sw_gid = pw->pw_gid;
 651                 } else {
 652                         if (errno)
 653                                 msyslog(LOG_ERR, "getpwnam(%s) failed: %m", user);
 654                         else
 655                                 msyslog(LOG_ERR, "Cannot find user `%s'", user);
 656                         return 0;
 657                 }
 658         }
 659
 660         return 1;
 661 }
 662
 663 /*
 664  * Map group name/number to group ID
 665 */
 666 static int
 667 map_group(void)
 668 {
 669         char *endp;
 670
 671         if (isdigit((unsigned char)*group)) {
 672                 sw_gid = (gid_t)strtoul(group, &endp, 0);
 673                 if (*endp != '\0')
 674                         goto getgroup;
 675         } else {
 676 getgroup:
 677                 if ((gr = getgrnam(group)) != NULL) {
 678                         sw_gid = gr->gr_gid;
 679                 } else {
 680                         errno = 0;
 681                         msyslog(LOG_ERR, "Cannot find group `%s'", group);
 682                         return 0;
 683                 }
 684         }
 685
 686         return 1;
 687 }
 688
 689 static int
 690 set_group_ids(void)
 691 {
 692         if (user && initgroups(user, sw_gid)) {
 693                 msyslog(LOG_ERR, "Cannot initgroups() to user `%s': %m", user);
 694                 return 0;
 695         }
 696         if (group && setgid(sw_gid)) {
 697                 msyslog(LOG_ERR, "Cannot setgid() to group `%s': %m", group);
 698                 return 0;
 699         }
 700         if (group && setegid(sw_gid)) {
 701                 msyslog(LOG_ERR, "Cannot setegid() to group `%s': %m", group);
 702                 return 0;
 703         }
 704         if (group) {
 705                 if (0 != setgroups(1, &sw_gid)) {
 706                         msyslog(LOG_ERR, "setgroups(1, %d) failed: %m", sw_gid);
 707                         return 0;
 708                 }
 709         }
 710         else if (pw)
 711                 if (0 != initgroups(pw->pw_name, pw->pw_gid)) {
 712                         msyslog(LOG_ERR, "initgroups(<%s>, %d) filed: %m", pw->pw_name, pw->pw_gid);
 713                         return 0;
 714                 }
 715         return 1;
 716 }
 717
 718 static int
 719 set_user_ids(void)
 720 {
 721         if (user && setuid(sw_uid)) {
 722                 msyslog(LOG_ERR, "Cannot setuid() to user `%s': %m", user);
 723                 return 0;
 724         }
 725         if (user && seteuid(sw_uid)) {
 726                 msyslog(LOG_ERR, "Cannot seteuid() to user `%s': %m", user);
 727                 return 0;
 728         }
 729         return 1;
 730 }
 731
 732 /*
 733  * Change (effective) user and group IDs, also initialize the supplementary group access list
 734  */
 735 int set_user_group_ids(void);
 736 int
 737 set_user_group_ids(void)
 738 {
 739         /* If the the user was already mapped, no need to map it again */
 740         if ((NULL != user) && (0 == sw_uid)) {
 741                 if (0 == map_user())
 742                         exit (-1);
 743         }
 744         /* same applies for the group */
 745         if ((NULL != group) && (0 == sw_gid)) {
 746                 if (0 == map_group())
 747                         exit (-1);
 748         }
 749
 750         if (getegid() != sw_gid && 0 == set_group_ids())
 751                 return 0;
 752         if (geteuid() != sw_uid && 0 == set_user_ids())
 753                 return 0;
 754
 755         return 1;
 756 }
 757 #endif /* HAVE_DROPROOT */
 758 #endif /* !SIM */
 759
 760 /*
 761  * Main program.  Initialize us, disconnect us from the tty if necessary,
 762  * and loop waiting for I/O and/or timer expiries.
 763  */
 764 #ifndef SIM
 765 int
 766 ntpdmain(
 767         int argc,
 768         char *argv[]
 769         )
 770 {
 771         l_fp            now;
 772         struct recvbuf *rbuf;
 773         const char *    logfilename;
 774 # ifdef HAVE_UMASK
 775         mode_t          uv;
 776 # endif
 777 # if defined(HAVE_GETUID) && !defined(MPE) /* MPE lacks the concept of root */
 778         uid_t           uid;
 779 # endif
 780 # if defined(HAVE_WORKING_FORK)
 781         long            wait_sync = 0;
 782         int             pipe_fds[2];
 783         int             rc;
 784         int             exit_code;
 785 # endif /* HAVE_WORKING_FORK*/
 786 # ifdef SCO5_CLOCK
 787         int             fd;
 788         int             zero;
 789 # endif
 790
 791 # ifdef NEED_PTHREAD_WARMUP
 792         my_pthread_warmup();
 793 # endif
 794
 795 # ifdef HAVE_UMASK
 796         uv = umask(0);
 797         if (uv)
 798                 umask(uv);
 799         else
 800                 umask(022);
 801 # endif
 802         saved_argc = argc;
 803         saved_argv = argv;
 804         progname = argv[0];
 805         initializing = TRUE;            /* mark that we are initializing */
 806         parse_cmdline_opts(&argc, &argv);
 807 # ifdef DEBUG
 808         debug = OPT_VALUE_SET_DEBUG_LEVEL;
 809 #  ifdef HAVE_SETLINEBUF
 810         setlinebuf(stdout);
 811 #  endif
 812 # endif
 813
 814         if (HAVE_OPT(NOFORK) || HAVE_OPT(QUIT)
 815 # ifdef DEBUG
 816             || debug
 817 # endif
 818             || HAVE_OPT(SAVECONFIGQUIT))
 819                 nofork = TRUE;
 820
 821         init_logging(progname, NLOG_SYNCMASK, TRUE);
 822         /* honor -l/--logfile option to log to a file */
 823         if (HAVE_OPT(LOGFILE)) {
 824                 logfilename = OPT_ARG(LOGFILE);
 825                 syslogit = FALSE;
 826                 change_logfile(logfilename, FALSE);
 827         } else {
 828                 logfilename = NULL;
 829                 if (nofork)
 830                         msyslog_term = TRUE;
 831                 if (HAVE_OPT(SAVECONFIGQUIT))
 832                         syslogit = FALSE;
 833         }
 834         msyslog(LOG_NOTICE, "%s: Starting", Version);
 835
 836         {
 837                 int i;
 838                 char buf[1024]; /* Secret knowledge of msyslog buf length */
 839                 char *cp = buf;
 840
 841                 /* Note that every arg has an initial space character */
 842                 snprintf(cp, sizeof(buf), "Command line:");
 843                 cp += strlen(cp);
 844
 845                 for (i = 0; i < saved_argc ; ++i) {
 846                         snprintf(cp, sizeof(buf) - (cp - buf),
 847                                 " %s", saved_argv[i]);
 848                         cp += strlen(cp);
 849                 }
 850                 msyslog(LOG_INFO, "%s", buf);
 851         }
 852
 853         /*
 854          * Install trap handlers to log errors and assertion failures.
 855          * Default handlers print to stderr which doesn't work if detached.
 856          */
 857         isc_assertion_setcallback(assertion_failed);
 858         isc_error_setfatal(library_fatal_error);
 859         isc_error_setunexpected(library_unexpected_error);
 860
 861         /* MPE lacks the concept of root */
 862 # if defined(HAVE_GETUID) && !defined(MPE)
 863         uid = getuid();
 864         if (uid && !HAVE_OPT( SAVECONFIGQUIT )) {
 865                 msyslog_term = TRUE;
 866                 msyslog(LOG_ERR,
 867                         "must be run as root, not uid %ld", (long)uid);
 868                 exit(1);
 869         }
 870 # endif
 871
 872 /*
 873  * Enable the Multi-Media Timer for Windows?
 874  */
 875 # ifdef SYS_WINNT
 876         if (HAVE_OPT( MODIFYMMTIMER ))
 877                 set_mm_timer(MM_TIMER_HIRES);
 878 # endif
 879
 880 #ifdef HAVE_DNSREGISTRATION
 881 /*
 882  * Enable mDNS registrations?
 883  */
 884         if (HAVE_OPT( MDNS )) {
 885                 mdnsreg = TRUE;
 886         }
 887 #endif  /* HAVE_DNSREGISTRATION */
 888
 889         if (HAVE_OPT( NOVIRTUALIPS ))
 890                 listen_to_virtual_ips = 0;
 891
 892         /*
 893          * --interface, listen on specified interfaces
 894          */
 895         if (HAVE_OPT( INTERFACE )) {
 896                 int             ifacect = STACKCT_OPT( INTERFACE );
 897                 const char**    ifaces  = STACKLST_OPT( INTERFACE );
 898                 sockaddr_u      addr;
 899
 900                 while (ifacect-- > 0) {
 901                         add_nic_rule(
 902                                 is_ip_address(*ifaces, AF_UNSPEC, &addr)
 903                                         ? MATCH_IFADDR
 904                                         : MATCH_IFNAME,
 905                                 *ifaces, -1, ACTION_LISTEN);
 906                         ifaces++;
 907                 }
 908         }
 909
 910         if (HAVE_OPT( NICE ))
 911                 priority_done = 0;
 912
 913 # ifdef HAVE_SCHED_SETSCHEDULER
 914         if (HAVE_OPT( PRIORITY )) {
 915                 config_priority = OPT_VALUE_PRIORITY;
 916                 config_priority_override = 1;
 917                 priority_done = 0;
 918         }
 919 # endif
 920
 921 # ifdef HAVE_WORKING_FORK
 922         /* make sure the FDs are initialised */
 923         pipe_fds[0] = -1;
 924         pipe_fds[1] = -1;
 925         do {                                    /* 'loop' once */
 926                 if (!HAVE_OPT( WAIT_SYNC ))
 927                         break;
 928                 wait_sync = OPT_VALUE_WAIT_SYNC;
 929                 if (wait_sync <= 0) {
 930                         wait_sync = 0;
 931                         break;
 932                 }
 933                 /* -w requires a fork() even with debug > 0 */
 934                 nofork = FALSE;
 935                 if (pipe(pipe_fds)) {
 936                         exit_code = (errno) ? errno : -1;
 937                         msyslog(LOG_ERR,
 938                                 "Pipe creation failed for --wait-sync: %m");
 939                         exit(exit_code);
 940                 }
 941                 waitsync_fd_to_close = pipe_fds[1];
 942         } while (0);                            /* 'loop' once */
 943 # endif /* HAVE_WORKING_FORK */
 944
 945         init_lib();
 946 # ifdef SYS_WINNT
 947         /*
 948          * Make sure the service is initialized before we do anything else
 949          */
 950         ntservice_init();
 951
 952         /*
 953          * Start interpolation thread, must occur before first
 954          * get_systime()
 955          */
 956         init_winnt_time();
 957 # endif
 958         /*
 959          * Initialize random generator and public key pair
 960          */
 961         get_systime(&now);
 962
 963         ntp_srandom((int)(now.l_i * now.l_uf));
 964
 965         /*
 966          * Detach us from the terminal.  May need an #ifndef GIZMO.
 967          */
 968         if (!nofork) {
 969
 970 # ifdef HAVE_WORKING_FORK
 971                 detach_from_terminal(pipe_fds, wait_sync, logfilename);
 972 # endif         /* HAVE_WORKING_FORK */
 973         }
 974
 975 # ifdef SCO5_CLOCK
 976         /*
 977          * SCO OpenServer's system clock offers much more precise timekeeping
 978          * on the base CPU than the other CPUs (for multiprocessor systems),
 979          * so we must lock to the base CPU.
 980          */
 981         fd = open("/dev/at1", O_RDONLY);
 982         if (fd >= 0) {
 983                 zero = 0;
 984                 if (ioctl(fd, ACPU_LOCK, &zero) < 0)
 985                         msyslog(LOG_ERR, "cannot lock to base CPU: %m");
 986                 close(fd);
 987         }
 988 # endif
 989
 990         /* Setup stack size in preparation for locking pages in memory. */
 991 # if defined(HAVE_MLOCKALL)
 992 #  ifdef HAVE_SETRLIMIT
 993         ntp_rlimit(RLIMIT_STACK, DFLT_RLIMIT_STACK * 4096, 4096, "4k");
 994 #   ifdef RLIMIT_MEMLOCK
 995         /*
 996          * The default RLIMIT_MEMLOCK is very low on Linux systems.
 997          * Unless we increase this limit malloc calls are likely to
 998          * fail if we drop root privilege.  To be useful the value
 999          * has to be larger than the largest ntpd resident set size.
1000          */
1001         ntp_rlimit(RLIMIT_MEMLOCK, DFLT_RLIMIT_MEMLOCK * 1024 * 1024, 1024 * 1024, "MB");
1002 #   endif       /* RLIMIT_MEMLOCK */
1003 #  endif        /* HAVE_SETRLIMIT */
1004 # else  /* !HAVE_MLOCKALL follows */
1005 #  ifdef HAVE_PLOCK
1006 #   ifdef PROCLOCK
1007 #    ifdef _AIX
1008         /*
1009          * set the stack limit for AIX for plock().
1010          * see get_aix_stack() for more info.
1011          */
1012         if (ulimit(SET_STACKLIM, (get_aix_stack() - 8 * 4096)) < 0)
1013                 msyslog(LOG_ERR,
1014                         "Cannot adjust stack limit for plock: %m");
1015 #    endif      /* _AIX */
1016 #   endif       /* PROCLOCK */
1017 #  endif        /* HAVE_PLOCK */
1018 # endif /* !HAVE_MLOCKALL */
1019
1020         /*
1021          * Set up signals we pay attention to locally.
1022          */
1023 # ifdef SIGDIE1
1024         signal_no_reset(SIGDIE1, finish);
1025         signal_no_reset(SIGDIE2, finish);
1026         signal_no_reset(SIGDIE3, finish);
1027         signal_no_reset(SIGDIE4, finish);
1028 # endif
1029 # ifdef SIGBUS
1030         signal_no_reset(SIGBUS, finish);
1031 # endif
1032
1033 # if !defined(SYS_WINNT) && !defined(VMS)
1034 #  ifdef DEBUG
1035         (void) signal_no_reset(MOREDEBUGSIG, moredebug);
1036         (void) signal_no_reset(LESSDEBUGSIG, lessdebug);
1037 #  else
1038         (void) signal_no_reset(MOREDEBUGSIG, no_debug);
1039         (void) signal_no_reset(LESSDEBUGSIG, no_debug);
1040 #  endif        /* DEBUG */
1041 # endif /* !SYS_WINNT && !VMS */
1042
1043         /*
1044          * Set up signals we should never pay attention to.
1045          */
1046 # ifdef SIGPIPE
1047         signal_no_reset(SIGPIPE, SIG_IGN);
1048 # endif
1049
1050         /*
1051          * Call the init_ routines to initialize the data structures.
1052          *
1053          * Exactly what command-line options are we expecting here?
1054          */
1055         INIT_SSL();
1056         init_auth();
1057         init_util();
1058         init_restrict();
1059         init_mon();
1060         init_timer();
1061         init_request();
1062         init_control();
1063         init_peer();
1064 # ifdef REFCLOCK
1065         init_refclock();
1066 # endif
1067         set_process_priority();
1068         init_proto();           /* Call at high priority */
1069         init_io();
1070         init_loopfilter();
1071         mon_start(MON_ON);      /* monitor on by default now      */
1072                                 /* turn off in config if unwanted */
1073
1074         /*
1075          * Get the configuration.  This is done in a separate module
1076          * since this will definitely be different for the gizmo board.
1077          */
1078         getconfig(argc, argv);
1079
1080         if (-1 == cur_memlock) {
1081 # if defined(HAVE_MLOCKALL)
1082                 /*
1083                  * lock the process into memory
1084                  */
1085                 if (   !HAVE_OPT(SAVECONFIGQUIT)
1086 #  ifdef RLIMIT_MEMLOCK
1087                     && -1 != DFLT_RLIMIT_MEMLOCK
1088 #  endif
1089                     && 0 != mlockall(MCL_CURRENT|MCL_FUTURE))
1090                         msyslog(LOG_ERR, "mlockall(): %m");
1091 # else  /* !HAVE_MLOCKALL follows */
1092 #  ifdef HAVE_PLOCK
1093 #   ifdef PROCLOCK
1094                 /*
1095                  * lock the process into memory
1096                  */
1097                 if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(PROCLOCK))
1098                         msyslog(LOG_ERR, "plock(PROCLOCK): %m");
1099 #   else        /* !PROCLOCK follows  */
1100 #    ifdef TXTLOCK
1101                 /*
1102                  * Lock text into ram
1103                  */
1104                 if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(TXTLOCK))
1105                         msyslog(LOG_ERR, "plock(TXTLOCK) error: %m");
1106 #    else       /* !TXTLOCK follows */
1107                 msyslog(LOG_ERR, "plock() - don't know what to lock!");
1108 #    endif      /* !TXTLOCK */
1109 #   endif       /* !PROCLOCK */
1110 #  endif        /* HAVE_PLOCK */
1111 # endif /* !HAVE_MLOCKALL */
1112         }
1113
1114         loop_config(LOOP_DRIFTINIT, 0);
1115         report_event(EVNT_SYSRESTART, NULL, NULL);
1116         initializing = FALSE;
1117
1118 # ifdef HAVE_DROPROOT
1119         if (droproot) {
1120
1121 #ifdef NEED_EARLY_FORK
1122                 fork_nonchroot_worker();
1123 #endif
1124
1125                 /* Drop super-user privileges and chroot now if the OS supports this */
1126
1127 #  ifdef HAVE_LINUX_CAPABILITIES
1128                 /* set flag: keep privileges accross setuid() call (we only really need cap_sys_time): */
1129                 if (prctl( PR_SET_KEEPCAPS, 1L, 0L, 0L, 0L ) == -1) {
1130                         msyslog( LOG_ERR, "prctl( PR_SET_KEEPCAPS, 1L ) failed: %m" );
1131                         exit(-1);
1132                 }
1133 #  elif HAVE_SOLARIS_PRIVS
1134                 /* Nothing to do here */
1135 #  else
1136                 /* we need a user to switch to */
1137                 if (user == NULL) {
1138                         msyslog(LOG_ERR, "Need user name to drop root privileges (see -u flag!)" );
1139                         exit(-1);
1140                 }
1141 #  endif        /* HAVE_LINUX_CAPABILITIES || HAVE_SOLARIS_PRIVS */
1142
1143                 if (user != NULL) {
1144                         if (0 == map_user())
1145                                 exit (-1);
1146                 }
1147                 if (group != NULL) {
1148                         if (0 == map_group())
1149                                 exit (-1);
1150                 }
1151
1152                 if (chrootdir ) {
1153                         /* make sure cwd is inside the jail: */
1154                         if (chdir(chrootdir)) {
1155                                 msyslog(LOG_ERR, "Cannot chdir() to `%s': %m", chrootdir);
1156                                 exit (-1);
1157                         }
1158                         if (chroot(chrootdir)) {
1159                                 msyslog(LOG_ERR, "Cannot chroot() to `%s': %m", chrootdir);
1160                                 exit (-1);
1161                         }
1162                         if (chdir("/")) {
1163                                 msyslog(LOG_ERR, "Cannot chdir() to`root after chroot(): %m");
1164                                 exit (-1);
1165                         }
1166                 }
1167 #  ifdef HAVE_SOLARIS_PRIVS
1168                 if ((lowprivs = priv_str_to_set(LOWPRIVS, ",", NULL)) == NULL) {
1169                         msyslog(LOG_ERR, "priv_str_to_set() failed:%m");
1170                         exit(-1);
1171                 }
1172                 if ((highprivs = priv_allocset()) == NULL) {
1173                         msyslog(LOG_ERR, "priv_allocset() failed:%m");
1174                         exit(-1);
1175                 }
1176                 (void) getppriv(PRIV_PERMITTED, highprivs);
1177                 (void) priv_intersect(highprivs, lowprivs);
1178                 if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1179                         msyslog(LOG_ERR, "setppriv() failed:%m");
1180                         exit(-1);
1181                 }
1182 #  endif /* HAVE_SOLARIS_PRIVS */
1183                 if (0 == set_user_group_ids())
1184                         exit(-1);
1185
1186 #  if !defined(HAVE_LINUX_CAPABILITIES) && !defined(HAVE_SOLARIS_PRIVS)
1187                 /*
1188                  * for now assume that the privilege to bind to privileged ports
1189                  * is associated with running with uid 0 - should be refined on
1190                  * ports that allow binding to NTP_PORT with uid != 0
1191                  */
1192                 disable_dynamic_updates |= (sw_uid != 0);  /* also notifies routing message listener */
1193 #  endif /* !HAVE_LINUX_CAPABILITIES && !HAVE_SOLARIS_PRIVS */
1194
1195                 if (disable_dynamic_updates && interface_interval) {
1196                         interface_interval = 0;
1197                         msyslog(LOG_INFO, "running as non-root disables dynamic interface tracking");
1198                 }
1199
1200 #  ifdef HAVE_LINUX_CAPABILITIES
1201                 {
1202                         /*
1203                          *  We may be running under non-root uid now, but we still hold full root privileges!
1204                          *  We drop all of them, except for the crucial one or two: cap_sys_time and
1205                          *  cap_net_bind_service if doing dynamic interface tracking.
1206                          */
1207                         cap_t caps;
1208                         char *captext;
1209
1210                         captext = (0 != interface_interval)
1211                                       ? "cap_sys_time,cap_net_bind_service=pe"
1212                                       : "cap_sys_time=pe";
1213                         caps = cap_from_text(captext);
1214                         if (!caps) {
1215                                 msyslog(LOG_ERR,
1216                                         "cap_from_text(%s) failed: %m",
1217                                         captext);
1218                                 exit(-1);
1219                         }
1220                         if (-1 == cap_set_proc(caps)) {
1221                                 msyslog(LOG_ERR,
1222                                         "cap_set_proc() failed to drop root privs: %m");
1223                                 exit(-1);
1224                         }
1225                         cap_free(caps);
1226                 }
1227 #  endif        /* HAVE_LINUX_CAPABILITIES */
1228 #  ifdef HAVE_SOLARIS_PRIVS
1229                 if (priv_delset(lowprivs, "proc_setid") == -1) {
1230                         msyslog(LOG_ERR, "priv_delset() failed:%m");
1231                         exit(-1);
1232                 }
1233                 if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1234                         msyslog(LOG_ERR, "setppriv() failed:%m");
1235                         exit(-1);
1236                 }
1237                 priv_freeset(lowprivs);
1238                 priv_freeset(highprivs);
1239 #  endif /* HAVE_SOLARIS_PRIVS */
1240                 root_dropped = TRUE;
1241                 fork_deferred_worker();
1242         }       /* if (droproot) */
1243 # endif /* HAVE_DROPROOT */
1244
1245 /* libssecomp sandboxing */
1246 #if defined (LIBSECCOMP) && (KERN_SECCOMP)
1247         scmp_filter_ctx ctx;
1248
1249         if ((ctx = seccomp_init(SCMP_ACT_KILL)) < 0)
1250                 msyslog(LOG_ERR, "%s: seccomp_init(SCMP_ACT_KILL) failed: %m", __func__);
1251         else {
1252                 msyslog(LOG_DEBUG, "%s: seccomp_init(SCMP_ACT_KILL) succeeded", __func__);
1253         }
1254
1255 #ifdef __x86_64__
1256 int scmp_sc[] = {
1257         SCMP_SYS(adjtimex),
1258         SCMP_SYS(bind),
1259         SCMP_SYS(brk),
1260         SCMP_SYS(chdir),
1261         SCMP_SYS(clock_gettime),
1262         SCMP_SYS(clock_settime),
1263         SCMP_SYS(close),
1264         SCMP_SYS(connect),
1265         SCMP_SYS(exit_group),
1266         SCMP_SYS(fstat),
1267         SCMP_SYS(fsync),
1268         SCMP_SYS(futex),
1269         SCMP_SYS(getitimer),
1270         SCMP_SYS(getsockname),
1271         SCMP_SYS(ioctl),
1272         SCMP_SYS(lseek),
1273         SCMP_SYS(madvise),
1274         SCMP_SYS(mmap),
1275         SCMP_SYS(munmap),
1276         SCMP_SYS(open),
1277         SCMP_SYS(poll),
1278         SCMP_SYS(read),
1279         SCMP_SYS(recvmsg),
1280         SCMP_SYS(rename),
1281         SCMP_SYS(rt_sigaction),
1282         SCMP_SYS(rt_sigprocmask),
1283         SCMP_SYS(rt_sigreturn),
1284         SCMP_SYS(select),
1285         SCMP_SYS(sendto),
1286         SCMP_SYS(setitimer),
1287         SCMP_SYS(setsid),
1288         SCMP_SYS(socket),
1289         SCMP_SYS(stat),
1290         SCMP_SYS(time),
1291         SCMP_SYS(write),
1292 };
1293 #endif
1294 #ifdef __i386__
1295 int scmp_sc[] = {
1296         SCMP_SYS(_newselect),
1297         SCMP_SYS(adjtimex),
1298         SCMP_SYS(brk),
1299         SCMP_SYS(chdir),
1300         SCMP_SYS(clock_gettime),
1301         SCMP_SYS(clock_settime),
1302         SCMP_SYS(close),
1303         SCMP_SYS(exit_group),
1304         SCMP_SYS(fsync),
1305         SCMP_SYS(futex),
1306         SCMP_SYS(getitimer),
1307         SCMP_SYS(madvise),
1308         SCMP_SYS(mmap),
1309         SCMP_SYS(mmap2),
1310         SCMP_SYS(munmap),
1311         SCMP_SYS(open),
1312         SCMP_SYS(poll),
1313         SCMP_SYS(read),
1314         SCMP_SYS(rename),
1315         SCMP_SYS(rt_sigaction),
1316         SCMP_SYS(rt_sigprocmask),
1317         SCMP_SYS(select),
1318         SCMP_SYS(setitimer),
1319         SCMP_SYS(setsid),
1320         SCMP_SYS(sigprocmask),
1321         SCMP_SYS(sigreturn),
1322         SCMP_SYS(socketcall),
1323         SCMP_SYS(stat64),
1324         SCMP_SYS(time),
1325         SCMP_SYS(write),
1326 };
1327 #endif
1328         {
1329                 int i;
1330
1331                 for (i = 0; i < COUNTOF(scmp_sc); i++) {
1332                         if (seccomp_rule_add(ctx,
1333                             SCMP_ACT_ALLOW, scmp_sc[i], 0) < 0) {
1334                                 msyslog(LOG_ERR,
1335                                     "%s: seccomp_rule_add() failed: %m",
1336                                     __func__);
1337                         }
1338                 }
1339         }
1340
1341         if (seccomp_load(ctx) < 0)
1342                 msyslog(LOG_ERR, "%s: seccomp_load() failed: %m",
1343                     __func__);
1344         else {
1345                 msyslog(LOG_DEBUG, "%s: seccomp_load() succeeded", __func__);
1346         }
1347 #endif /* LIBSECCOMP and KERN_SECCOMP */
1348
1349 #ifdef SYS_WINNT
1350         ntservice_isup();
1351 #endif
1352
1353 # ifdef HAVE_IO_COMPLETION_PORT
1354
1355         for (;;) {
1356 #if !defined(SIM) && defined(SIGDIE1)
1357                 if (signalled)
1358                         finish_safe(signo);
1359 #endif
1360                 GetReceivedBuffers();
1361 # else /* normal I/O */
1362
1363         BLOCK_IO_AND_ALARM();
1364         was_alarmed = FALSE;
1365
1366         for (;;) {
1367 #if !defined(SIM) && defined(SIGDIE1)
1368                 if (signalled)
1369                         finish_safe(signo);
1370 #endif
1371                 if (alarm_flag) {       /* alarmed? */
1372                         was_alarmed = TRUE;
1373                         alarm_flag = FALSE;
1374                 }
1375
1376                 /* collect async name/addr results */
1377                 if (!was_alarmed)
1378                     harvest_blocking_responses();
1379
1380                 if (!was_alarmed && !has_full_recv_buffer()) {
1381                         /*
1382                          * Nothing to do.  Wait for something.
1383                          */
1384                         io_handler();
1385                 }
1386
1387                 if (alarm_flag) {       /* alarmed? */
1388                         was_alarmed = TRUE;
1389                         alarm_flag = FALSE;
1390                 }
1391
1392                 if (was_alarmed) {
1393                         UNBLOCK_IO_AND_ALARM();
1394                         /*
1395                          * Out here, signals are unblocked.  Call timer routine
1396                          * to process expiry.
1397                          */
1398                         timer();
1399                         was_alarmed = FALSE;
1400                         BLOCK_IO_AND_ALARM();
1401                 }
1402
1403 # endif         /* !HAVE_IO_COMPLETION_PORT */
1404
1405 # ifdef DEBUG_TIMING
1406                 {
1407                         l_fp pts;
1408                         l_fp tsa, tsb;
1409                         int bufcount = 0;
1410
1411                         get_systime(&pts);
1412                         tsa = pts;
1413 # endif
1414                         rbuf = get_full_recv_buffer();
1415                         while (rbuf != NULL) {
1416                                 if (alarm_flag) {
1417                                         was_alarmed = TRUE;
1418                                         alarm_flag = FALSE;
1419                                 }
1420                                 UNBLOCK_IO_AND_ALARM();
1421
1422                                 if (was_alarmed) {
1423                                         /* avoid timer starvation during lengthy I/O handling */
1424                                         timer();
1425                                         was_alarmed = FALSE;
1426                                 }
1427
1428                                 /*
1429                                  * Call the data procedure to handle each received
1430                                  * packet.
1431                                  */
1432                                 if (rbuf->receiver != NULL) {
1433 # ifdef DEBUG_TIMING
1434                                         l_fp dts = pts;
1435
1436                                         L_SUB(&dts, &rbuf->recv_time);
1437                                         DPRINTF(2, ("processing timestamp delta %s (with prec. fuzz)\n", lfptoa(&dts, 9)));
1438                                         collect_timing(rbuf, "buffer processing delay", 1, &dts);
1439                                         bufcount++;
1440 # endif
1441                                         (*rbuf->receiver)(rbuf);
1442                                 } else {
1443                                         msyslog(LOG_ERR, "fatal: receive buffer callback NULL");
1444                                         abort();
1445                                 }
1446
1447                                 BLOCK_IO_AND_ALARM();
1448                                 freerecvbuf(rbuf);
1449                                 rbuf = get_full_recv_buffer();
1450                         }
1451 # ifdef DEBUG_TIMING
1452                         get_systime(&tsb);
1453                         L_SUB(&tsb, &tsa);
1454                         if (bufcount) {
1455                                 collect_timing(NULL, "processing", bufcount, &tsb);
1456                                 DPRINTF(2, ("processing time for %d buffers %s\n", bufcount, lfptoa(&tsb, 9)));
1457                         }
1458                 }
1459 # endif
1460
1461                 /*
1462                  * Go around again
1463                  */
1464
1465 # ifdef HAVE_DNSREGISTRATION
1466                 if (mdnsreg && (current_time - mdnsreg ) > 60 && mdnstries && sys_leap != LEAP_NOTINSYNC) {
1467                         mdnsreg = current_time;
1468                         msyslog(LOG_INFO, "Attempting to register mDNS");
1469                         if ( DNSServiceRegister (&mdns, 0, 0, NULL, "_ntp._udp", NULL, NULL,
1470                             htons(NTP_PORT), 0, NULL, NULL, NULL) != kDNSServiceErr_NoError ) {
1471                                 if (!--mdnstries) {
1472                                         msyslog(LOG_ERR, "Unable to register mDNS, giving up.");
1473                                 } else {
1474                                         msyslog(LOG_INFO, "Unable to register mDNS, will try later.");
1475                                 }
1476                         } else {
1477                                 msyslog(LOG_INFO, "mDNS service registered.");
1478                                 mdnsreg = FALSE;
1479                         }
1480                 }
1481 # endif /* HAVE_DNSREGISTRATION */
1482
1483         }
1484         UNBLOCK_IO_AND_ALARM();
1485         return 1;
1486 }
1487 #endif  /* !SIM */
1488
1489
1490 #if !defined(SIM) && defined(SIGDIE1)
1491 /*
1492  * finish - exit gracefully
1493  */
1494 static void
1495 finish_safe(
1496         int     sig
1497         )
1498 {
1499         const char *sig_desc;
1500
1501         sig_desc = NULL;
1502 #ifdef HAVE_STRSIGNAL
1503         sig_desc = strsignal(sig);
1504 #endif
1505         if (sig_desc == NULL)
1506                 sig_desc = "";
1507         msyslog(LOG_NOTICE, "%s exiting on signal %d (%s)", progname,
1508                 sig, sig_desc);
1509         /* See Bug 2513 and Bug 2522 re the unlink of PIDFILE */
1510 # ifdef HAVE_DNSREGISTRATION
1511         if (mdns != NULL)
1512                 DNSServiceRefDeallocate(mdns);
1513 # endif
1514         peer_cleanup();
1515         exit(0);
1516 }
1517
1518 static RETSIGTYPE
1519 finish(
1520         int     sig
1521         )
1522 {
1523         signalled = 1;
1524         signo = sig;
1525 }
1526
1527 #endif  /* !SIM && SIGDIE1 */
1528
1529
1530 #ifndef SIM
1531 /*
1532  * wait_child_sync_if - implements parent side of -w/--wait-sync
1533  */
1534 # ifdef HAVE_WORKING_FORK
1535 static int
1536 wait_child_sync_if(
1537         int     pipe_read_fd,
1538         long    wait_sync
1539         )
1540 {
1541         int     rc;
1542         int     exit_code;
1543         time_t  wait_end_time;
1544         time_t  cur_time;
1545         time_t  wait_rem;
1546         fd_set  readset;
1547         struct timeval wtimeout;
1548
1549         if (0 == wait_sync)
1550                 return 0;
1551
1552         /* waitsync_fd_to_close used solely by child */
1553         close(waitsync_fd_to_close);
1554         wait_end_time = time(NULL) + wait_sync;
1555         do {
1556                 cur_time = time(NULL);
1557                 wait_rem = (wait_end_time > cur_time)
1558                                 ? (wait_end_time - cur_time)
1559                                 : 0;
1560                 wtimeout.tv_sec = wait_rem;
1561                 wtimeout.tv_usec = 0;
1562                 FD_ZERO(&readset);
1563                 FD_SET(pipe_read_fd, &readset);
1564                 rc = select(pipe_read_fd + 1, &readset, NULL, NULL,
1565                             &wtimeout);
1566                 if (-1 == rc) {
1567                         if (EINTR == errno)
1568                                 continue;
1569                         exit_code = (errno) ? errno : -1;
1570                         msyslog(LOG_ERR,
1571                                 "--wait-sync select failed: %m");
1572                         return exit_code;
1573                 }
1574                 if (0 == rc) {
1575                         /*
1576                          * select() indicated a timeout, but in case
1577                          * its timeouts are affected by a step of the
1578                          * system clock, select() again with a zero
1579                          * timeout to confirm.
1580                          */
1581                         FD_ZERO(&readset);
1582                         FD_SET(pipe_read_fd, &readset);
1583                         wtimeout.tv_sec = 0;
1584                         wtimeout.tv_usec = 0;
1585                         rc = select(pipe_read_fd + 1, &readset, NULL,
1586                                     NULL, &wtimeout);
1587                         if (0 == rc)    /* select() timeout */
1588                                 break;
1589                         else            /* readable */
1590                                 return 0;
1591                 } else                  /* readable */
1592                         return 0;
1593         } while (wait_rem > 0);
1594
1595         fprintf(stderr, "%s: -w/--wait-sync %ld timed out.\n",
1596                 progname, wait_sync);
1597         return ETIMEDOUT;
1598 }
1599 # endif /* HAVE_WORKING_FORK */
1600
1601
1602 /*
1603  * assertion_failed - Redirect assertion failures to msyslog().
1604  */
1605 static void
1606 assertion_failed(
1607         const char *file,
1608         int line,
1609         isc_assertiontype_t type,
1610         const char *cond
1611         )
1612 {
1613         isc_assertion_setcallback(NULL);    /* Avoid recursion */
1614
1615         msyslog(LOG_ERR, "%s:%d: %s(%s) failed",
1616                 file, line, isc_assertion_typetotext(type), cond);
1617         msyslog(LOG_ERR, "exiting (due to assertion failure)");
1618
1619 #if defined(DEBUG) && defined(SYS_WINNT)
1620         if (debug)
1621                 DebugBreak();
1622 #endif
1623
1624         abort();
1625 }
1626
1627
1628 /*
1629  * library_fatal_error - Handle fatal errors from our libraries.
1630  */
1631 static void
1632 library_fatal_error(
1633         const char *file,
1634         int line,
1635         const char *format,
1636         va_list args
1637         )
1638 {
1639         char errbuf[256];
1640
1641         isc_error_setfatal(NULL);  /* Avoid recursion */
1642
1643         msyslog(LOG_ERR, "%s:%d: fatal error:", file, line);
1644         vsnprintf(errbuf, sizeof(errbuf), format, args);
1645         msyslog(LOG_ERR, "%s", errbuf);
1646         msyslog(LOG_ERR, "exiting (due to fatal error in library)");
1647
1648 #if defined(DEBUG) && defined(SYS_WINNT)
1649         if (debug)
1650                 DebugBreak();
1651 #endif
1652
1653         abort();
1654 }
1655
1656
1657 /*
1658  * library_unexpected_error - Handle non fatal errors from our libraries.
1659  */
1660 # define MAX_UNEXPECTED_ERRORS 100
1661 int unexpected_error_cnt = 0;
1662 static void
1663 library_unexpected_error(
1664         const char *file,
1665         int line,
1666         const char *format,
1667         va_list args
1668         )
1669 {
1670         char errbuf[256];
1671
1672         if (unexpected_error_cnt >= MAX_UNEXPECTED_ERRORS)
1673                 return; /* avoid clutter in log */
1674
1675         msyslog(LOG_ERR, "%s:%d: unexpected error:", file, line);
1676         vsnprintf(errbuf, sizeof(errbuf), format, args);
1677         msyslog(LOG_ERR, "%s", errbuf);
1678
1679         if (++unexpected_error_cnt == MAX_UNEXPECTED_ERRORS)
1680                 msyslog(LOG_ERR, "Too many errors.  Shutting up.");
1681
1682 }
1683 #endif  /* !SIM */
1684
1685 #if !defined(SIM) && !defined(SYS_WINNT)
1686 # ifdef DEBUG
1687
1688 /*
1689  * moredebug - increase debugging verbosity
1690  */
1691 static RETSIGTYPE
1692 moredebug(
1693         int sig
1694         )
1695 {
1696         int saved_errno = errno;
1697
1698         if (debug < 255)
1699         {
1700                 debug++;
1701                 msyslog(LOG_DEBUG, "debug raised to %d", debug);
1702         }
1703         errno = saved_errno;
1704 }
1705
1706
1707 /*
1708  * lessdebug - decrease debugging verbosity
1709  */
1710 static RETSIGTYPE
1711 lessdebug(
1712         int sig
1713         )
1714 {
1715         int saved_errno = errno;
1716
1717         if (debug > 0)
1718         {
1719                 debug--;
1720                 msyslog(LOG_DEBUG, "debug lowered to %d", debug);
1721         }
1722         errno = saved_errno;
1723 }
1724
1725 # else  /* !DEBUG follows */
1726
1727
1728 /*
1729  * no_debug - We don't do the debug here.
1730  */
1731 static RETSIGTYPE
1732 no_debug(
1733         int sig
1734         )
1735 {
1736         int saved_errno = errno;
1737
1738         msyslog(LOG_DEBUG, "ntpd not compiled for debugging (signal %d)", sig);
1739         errno = saved_errno;
1740 }
1741 # endif /* !DEBUG */
1742 #endif  /* !SIM && !SYS_WINNT */