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 static void
 535 detach_from_terminal(
 536         int pipe_fds[2],
 537         long wait_sync,
 538         const char *logfilename
 539         )
 540 {
 541         int rc;
 542         int exit_code;
 543 #  if !defined(HAVE_SETSID) && !defined (HAVE_SETPGID) && defined(TIOCNOTTY)
 544         int             fid;
 545 #  endif
 546 #  ifdef _AIX
 547         struct sigaction sa;
 548 #  endif
 549
 550         rc = fork();
 551         if (-1 == rc) {
 552                 exit_code = (errno) ? errno : -1;
 553                 msyslog(LOG_ERR, "fork: %m");
 554                 exit(exit_code);
 555         }
 556         if (rc > 0) {
 557                 /* parent */
 558                 exit_code = wait_child_sync_if(pipe_fds[0],
 559                                                wait_sync);
 560                 exit(exit_code);
 561         }
 562
 563         /*
 564          * child/daemon
 565          * close all open files excepting waitsync_fd_to_close.
 566          * msyslog() unreliable until after init_logging().
 567          */
 568         closelog();
 569         if (syslog_file != NULL) {
 570                 fclose(syslog_file);
 571                 syslog_file = NULL;
 572                 syslogit = TRUE;
 573         }
 574         close_all_except(waitsync_fd_to_close);
 575         INSIST(0 == open("/dev/null", 0) && 1 == dup2(0, 1) \
 576                 && 2 == dup2(0, 2));
 577
 578         init_logging(progname, 0, TRUE);
 579         /* we lost our logfile (if any) daemonizing */
 580         setup_logfile(logfilename);
 581
 582 #  ifdef SYS_DOMAINOS
 583         {
 584                 uid_$t puid;
 585                 status_$t st;
 586
 587                 proc2_$who_am_i(&puid);
 588                 proc2_$make_server(&puid, &st);
 589         }
 590 #  endif        /* SYS_DOMAINOS */
 591 #  ifdef HAVE_SETSID
 592         if (setsid() == (pid_t)-1)
 593                 msyslog(LOG_ERR, "setsid(): %m");
 594 #  elif defined(HAVE_SETPGID)
 595         if (setpgid(0, 0) == -1)
 596                 msyslog(LOG_ERR, "setpgid(): %m");
 597 #  else         /* !HAVE_SETSID && !HAVE_SETPGID follows */
 598 #   ifdef TIOCNOTTY
 599         fid = open("/dev/tty", 2);
 600         if (fid >= 0) {
 601                 ioctl(fid, (u_long)TIOCNOTTY, NULL);
 602                 close(fid);
 603         }
 604 #   endif       /* TIOCNOTTY */
 605         ntp_setpgrp(0, getpid());
 606 #  endif        /* !HAVE_SETSID && !HAVE_SETPGID */
 607 #  ifdef _AIX
 608         /* Don't get killed by low-on-memory signal. */
 609         sa.sa_handler = catch_danger;
 610         sigemptyset(&sa.sa_mask);
 611         sa.sa_flags = SA_RESTART;
 612         sigaction(SIGDANGER, &sa, NULL);
 613 #  endif        /* _AIX */
 614
 615         return;
 616 }
 617
 618 #ifdef HAVE_DROPROOT
 619 /*
 620  * Map user name/number to user ID
 621 */
 622 static int
 623 map_user(
 624         )
 625 {
 626         char *endp;
 627
 628         if (isdigit((unsigned char)*user)) {
 629                 sw_uid = (uid_t)strtoul(user, &endp, 0);
 630                 if (*endp != '\0')
 631                         goto getuser;
 632
 633                 if ((pw = getpwuid(sw_uid)) != NULL) {
 634                         free(user);
 635                         user = estrdup(pw->pw_name);
 636                         sw_gid = pw->pw_gid;
 637                 } else {
 638                         errno = 0;
 639                         msyslog(LOG_ERR, "Cannot find user ID %s", user);
 640                         return 0;
 641                 }
 642
 643         } else {
 644 getuser:
 645                 errno = 0;
 646                 if ((pw = getpwnam(user)) != NULL) {
 647                         sw_uid = pw->pw_uid;
 648                         sw_gid = pw->pw_gid;
 649                 } else {
 650                         if (errno)
 651                                 msyslog(LOG_ERR, "getpwnam(%s) failed: %m", user);
 652                         else
 653                                 msyslog(LOG_ERR, "Cannot find user `%s'", user);
 654                         return 0;
 655                 }
 656         }
 657
 658         return 1;
 659 }
 660
 661 /*
 662  * Map group name/number to group ID
 663 */
 664 static int
 665 map_group(
 666         )
 667 {
 668         char *endp;
 669
 670         if (isdigit((unsigned char)*group)) {
 671                 sw_gid = (gid_t)strtoul(group, &endp, 0);
 672                 if (*endp != '\0')
 673                         goto getgroup;
 674         } else {
 675 getgroup:
 676                 if ((gr = getgrnam(group)) != NULL) {
 677                         sw_gid = gr->gr_gid;
 678                 } else {
 679                         errno = 0;
 680                         msyslog(LOG_ERR, "Cannot find group `%s'", group);
 681                         return 0;
 682                 }
 683         }
 684
 685         return 1;
 686 }
 687
 688 /*
 689  * Change (effective) user and group IDs, also initialize the supplementary group access list
 690  */
 691 int
 692 set_user_group_ids(
 693         )
 694 {
 695         /* If the the user was already mapped, no need to map it again */
 696         if ((NULL != user) && (0 == sw_uid)) {
 697                 if (0 == map_user())
 698                         exit (-1);
 699         }
 700         /* same applies for the group */
 701         if ((NULL != group) && (0 == sw_gid)) {
 702                 if (0 == map_group())
 703                         exit (-1);
 704         }
 705
 706         if (user && initgroups(user, sw_gid)) {
 707                 msyslog(LOG_ERR, "Cannot initgroups() to user `%s': %m", user);
 708                 return 0;
 709         }
 710         if (group && setgid(sw_gid)) {
 711                 msyslog(LOG_ERR, "Cannot setgid() to group `%s': %m", group);
 712                 return 0;
 713         }
 714         if (group && setegid(sw_gid)) {
 715                 msyslog(LOG_ERR, "Cannot setegid() to group `%s': %m", group);
 716                 return 0;
 717         }
 718         if (group) {
 719                 if (0 != setgroups(1, &sw_gid)) {
 720                         msyslog(LOG_ERR, "setgroups(1, %d) failed: %m", sw_gid);
 721                         return 0;
 722                 }
 723         }
 724         else if (pw)
 725                 if (0 != initgroups(pw->pw_name, pw->pw_gid)) {
 726                         msyslog(LOG_ERR, "initgroups(<%s>, %d) filed: %m", pw->pw_name, pw->pw_gid);
 727                         return 0;
 728                 }
 729         if (user && setuid(sw_uid)) {
 730                 msyslog(LOG_ERR, "Cannot setuid() to user `%s': %m", user);
 731                 return 0;
 732         }
 733         if (user && seteuid(sw_uid)) {
 734                 msyslog(LOG_ERR, "Cannot seteuid() to user `%s': %m", user);
 735                 return 0;
 736         }
 737
 738         return 1;
 739 }
 740 #endif /* HAVE_DROPROOT */
 741 #endif /* !SIM */
 742
 743 /*
 744  * Main program.  Initialize us, disconnect us from the tty if necessary,
 745  * and loop waiting for I/O and/or timer expiries.
 746  */
 747 #ifndef SIM
 748 int
 749 ntpdmain(
 750         int argc,
 751         char *argv[]
 752         )
 753 {
 754         l_fp            now;
 755         struct recvbuf *rbuf;
 756         const char *    logfilename;
 757 # ifdef HAVE_UMASK
 758         mode_t          uv;
 759 # endif
 760 # if defined(HAVE_GETUID) && !defined(MPE) /* MPE lacks the concept of root */
 761         uid_t           uid;
 762 # endif
 763 # if defined(HAVE_WORKING_FORK)
 764         long            wait_sync = 0;
 765         int             pipe_fds[2];
 766         int             rc;
 767         int             exit_code;
 768 # endif /* HAVE_WORKING_FORK*/
 769 # ifdef SCO5_CLOCK
 770         int             fd;
 771         int             zero;
 772 # endif
 773
 774 # ifdef NEED_PTHREAD_WARMUP
 775         my_pthread_warmup();
 776 # endif
 777
 778 # ifdef HAVE_UMASK
 779         uv = umask(0);
 780         if (uv)
 781                 umask(uv);
 782         else
 783                 umask(022);
 784 # endif
 785         saved_argc = argc;
 786         saved_argv = argv;
 787         progname = argv[0];
 788         initializing = TRUE;            /* mark that we are initializing */
 789         parse_cmdline_opts(&argc, &argv);
 790 # ifdef DEBUG
 791         debug = OPT_VALUE_SET_DEBUG_LEVEL;
 792 #  ifdef HAVE_SETLINEBUF
 793         setlinebuf(stdout);
 794 #  endif
 795 # endif
 796
 797         if (HAVE_OPT(NOFORK) || HAVE_OPT(QUIT)
 798 # ifdef DEBUG
 799             || debug
 800 # endif
 801             || HAVE_OPT(SAVECONFIGQUIT))
 802                 nofork = TRUE;
 803
 804         init_logging(progname, NLOG_SYNCMASK, TRUE);
 805         /* honor -l/--logfile option to log to a file */
 806         if (HAVE_OPT(LOGFILE)) {
 807                 logfilename = OPT_ARG(LOGFILE);
 808                 syslogit = FALSE;
 809                 change_logfile(logfilename, FALSE);
 810         } else {
 811                 logfilename = NULL;
 812                 if (nofork)
 813                         msyslog_term = TRUE;
 814                 if (HAVE_OPT(SAVECONFIGQUIT))
 815                         syslogit = FALSE;
 816         }
 817         msyslog(LOG_NOTICE, "%s: Starting", Version);
 818
 819         {
 820                 int i;
 821                 char buf[1024]; /* Secret knowledge of msyslog buf length */
 822                 char *cp = buf;
 823
 824                 /* Note that every arg has an initial space character */
 825                 snprintf(cp, sizeof(buf), "Command line:");
 826                 cp += strlen(cp);
 827
 828                 for (i = 0; i < saved_argc ; ++i) {
 829                         snprintf(cp, sizeof(buf) - (cp - buf),
 830                                 " %s", saved_argv[i]);
 831                         cp += strlen(cp);
 832                 }
 833                 msyslog(LOG_INFO, "%s", buf);
 834         }
 835
 836         /*
 837          * Install trap handlers to log errors and assertion failures.
 838          * Default handlers print to stderr which doesn't work if detached.
 839          */
 840         isc_assertion_setcallback(assertion_failed);
 841         isc_error_setfatal(library_fatal_error);
 842         isc_error_setunexpected(library_unexpected_error);
 843
 844         /* MPE lacks the concept of root */
 845 # if defined(HAVE_GETUID) && !defined(MPE)
 846         uid = getuid();
 847         if (uid && !HAVE_OPT( SAVECONFIGQUIT )) {
 848                 msyslog_term = TRUE;
 849                 msyslog(LOG_ERR,
 850                         "must be run as root, not uid %ld", (long)uid);
 851                 exit(1);
 852         }
 853 # endif
 854
 855 /*
 856  * Enable the Multi-Media Timer for Windows?
 857  */
 858 # ifdef SYS_WINNT
 859         if (HAVE_OPT( MODIFYMMTIMER ))
 860                 set_mm_timer(MM_TIMER_HIRES);
 861 # endif
 862
 863 #ifdef HAVE_DNSREGISTRATION
 864 /*
 865  * Enable mDNS registrations?
 866  */
 867         if (HAVE_OPT( MDNS )) {
 868                 mdnsreg = TRUE;
 869         }
 870 #endif  /* HAVE_DNSREGISTRATION */
 871
 872         if (HAVE_OPT( NOVIRTUALIPS ))
 873                 listen_to_virtual_ips = 0;
 874
 875         /*
 876          * --interface, listen on specified interfaces
 877          */
 878         if (HAVE_OPT( INTERFACE )) {
 879                 int             ifacect = STACKCT_OPT( INTERFACE );
 880                 const char**    ifaces  = STACKLST_OPT( INTERFACE );
 881                 sockaddr_u      addr;
 882
 883                 while (ifacect-- > 0) {
 884                         add_nic_rule(
 885                                 is_ip_address(*ifaces, AF_UNSPEC, &addr)
 886                                         ? MATCH_IFADDR
 887                                         : MATCH_IFNAME,
 888                                 *ifaces, -1, ACTION_LISTEN);
 889                         ifaces++;
 890                 }
 891         }
 892
 893         if (HAVE_OPT( NICE ))
 894                 priority_done = 0;
 895
 896 # ifdef HAVE_SCHED_SETSCHEDULER
 897         if (HAVE_OPT( PRIORITY )) {
 898                 config_priority = OPT_VALUE_PRIORITY;
 899                 config_priority_override = 1;
 900                 priority_done = 0;
 901         }
 902 # endif
 903
 904 # ifdef HAVE_WORKING_FORK
 905         /* make sure the FDs are initialised */
 906         pipe_fds[0] = -1;
 907         pipe_fds[1] = -1;
 908         do {                                    /* 'loop' once */
 909                 if (!HAVE_OPT( WAIT_SYNC ))
 910                         break;
 911                 wait_sync = OPT_VALUE_WAIT_SYNC;
 912                 if (wait_sync <= 0) {
 913                         wait_sync = 0;
 914                         break;
 915                 }
 916                 /* -w requires a fork() even with debug > 0 */
 917                 nofork = FALSE;
 918                 if (pipe(pipe_fds)) {
 919                         exit_code = (errno) ? errno : -1;
 920                         msyslog(LOG_ERR,
 921                                 "Pipe creation failed for --wait-sync: %m");
 922                         exit(exit_code);
 923                 }
 924                 waitsync_fd_to_close = pipe_fds[1];
 925         } while (0);                            /* 'loop' once */
 926 # endif /* HAVE_WORKING_FORK */
 927
 928         init_lib();
 929 # ifdef SYS_WINNT
 930         /*
 931          * Make sure the service is initialized before we do anything else
 932          */
 933         ntservice_init();
 934
 935         /*
 936          * Start interpolation thread, must occur before first
 937          * get_systime()
 938          */
 939         init_winnt_time();
 940 # endif
 941         /*
 942          * Initialize random generator and public key pair
 943          */
 944         get_systime(&now);
 945
 946         ntp_srandom((int)(now.l_i * now.l_uf));
 947
 948         /*
 949          * Detach us from the terminal.  May need an #ifndef GIZMO.
 950          */
 951         if (!nofork) {
 952
 953 # ifdef HAVE_WORKING_FORK
 954                 detach_from_terminal(pipe_fds, wait_sync, logfilename);
 955 # endif         /* HAVE_WORKING_FORK */
 956         }
 957
 958 # ifdef SCO5_CLOCK
 959         /*
 960          * SCO OpenServer's system clock offers much more precise timekeeping
 961          * on the base CPU than the other CPUs (for multiprocessor systems),
 962          * so we must lock to the base CPU.
 963          */
 964         fd = open("/dev/at1", O_RDONLY);
 965         if (fd >= 0) {
 966                 zero = 0;
 967                 if (ioctl(fd, ACPU_LOCK, &zero) < 0)
 968                         msyslog(LOG_ERR, "cannot lock to base CPU: %m");
 969                 close(fd);
 970         }
 971 # endif
 972
 973         /* Setup stack size in preparation for locking pages in memory. */
 974 # if defined(HAVE_MLOCKALL)
 975 #  ifdef HAVE_SETRLIMIT
 976         ntp_rlimit(RLIMIT_STACK, DFLT_RLIMIT_STACK * 4096, 4096, "4k");
 977 #   ifdef RLIMIT_MEMLOCK
 978         /*
 979          * The default RLIMIT_MEMLOCK is very low on Linux systems.
 980          * Unless we increase this limit malloc calls are likely to
 981          * fail if we drop root privilege.  To be useful the value
 982          * has to be larger than the largest ntpd resident set size.
 983          */
 984         ntp_rlimit(RLIMIT_MEMLOCK, DFLT_RLIMIT_MEMLOCK * 1024 * 1024, 1024 * 1024, "MB");
 985 #   endif       /* RLIMIT_MEMLOCK */
 986 #  endif        /* HAVE_SETRLIMIT */
 987 # else  /* !HAVE_MLOCKALL follows */
 988 #  ifdef HAVE_PLOCK
 989 #   ifdef PROCLOCK
 990 #    ifdef _AIX
 991         /*
 992          * set the stack limit for AIX for plock().
 993          * see get_aix_stack() for more info.
 994          */
 995         if (ulimit(SET_STACKLIM, (get_aix_stack() - 8 * 4096)) < 0)
 996                 msyslog(LOG_ERR,
 997                         "Cannot adjust stack limit for plock: %m");
 998 #    endif      /* _AIX */
 999 #   endif       /* PROCLOCK */
1000 #  endif        /* HAVE_PLOCK */
1001 # endif /* !HAVE_MLOCKALL */
1002
1003         /*
1004          * Set up signals we pay attention to locally.
1005          */
1006 # ifdef SIGDIE1
1007         signal_no_reset(SIGDIE1, finish);
1008         signal_no_reset(SIGDIE2, finish);
1009         signal_no_reset(SIGDIE3, finish);
1010         signal_no_reset(SIGDIE4, finish);
1011 # endif
1012 # ifdef SIGBUS
1013         signal_no_reset(SIGBUS, finish);
1014 # endif
1015
1016 # if !defined(SYS_WINNT) && !defined(VMS)
1017 #  ifdef DEBUG
1018         (void) signal_no_reset(MOREDEBUGSIG, moredebug);
1019         (void) signal_no_reset(LESSDEBUGSIG, lessdebug);
1020 #  else
1021         (void) signal_no_reset(MOREDEBUGSIG, no_debug);
1022         (void) signal_no_reset(LESSDEBUGSIG, no_debug);
1023 #  endif        /* DEBUG */
1024 # endif /* !SYS_WINNT && !VMS */
1025
1026         /*
1027          * Set up signals we should never pay attention to.
1028          */
1029 # ifdef SIGPIPE
1030         signal_no_reset(SIGPIPE, SIG_IGN);
1031 # endif
1032
1033         /*
1034          * Call the init_ routines to initialize the data structures.
1035          *
1036          * Exactly what command-line options are we expecting here?
1037          */
1038         INIT_SSL();
1039         init_auth();
1040         init_util();
1041         init_restrict();
1042         init_mon();
1043         init_timer();
1044         init_request();
1045         init_control();
1046         init_peer();
1047 # ifdef REFCLOCK
1048         init_refclock();
1049 # endif
1050         set_process_priority();
1051         init_proto();           /* Call at high priority */
1052         init_io();
1053         init_loopfilter();
1054         mon_start(MON_ON);      /* monitor on by default now      */
1055                                 /* turn off in config if unwanted */
1056
1057         /*
1058          * Get the configuration.  This is done in a separate module
1059          * since this will definitely be different for the gizmo board.
1060          */
1061         getconfig(argc, argv);
1062
1063         if (-1 == cur_memlock) {
1064 # if defined(HAVE_MLOCKALL)
1065                 /*
1066                  * lock the process into memory
1067                  */
1068                 if (   !HAVE_OPT(SAVECONFIGQUIT)
1069 #  ifdef RLIMIT_MEMLOCK
1070                     && -1 != DFLT_RLIMIT_MEMLOCK
1071 #  endif
1072                     && 0 != mlockall(MCL_CURRENT|MCL_FUTURE))
1073                         msyslog(LOG_ERR, "mlockall(): %m");
1074 # else  /* !HAVE_MLOCKALL follows */
1075 #  ifdef HAVE_PLOCK
1076 #   ifdef PROCLOCK
1077                 /*
1078                  * lock the process into memory
1079                  */
1080                 if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(PROCLOCK))
1081                         msyslog(LOG_ERR, "plock(PROCLOCK): %m");
1082 #   else        /* !PROCLOCK follows  */
1083 #    ifdef TXTLOCK
1084                 /*
1085                  * Lock text into ram
1086                  */
1087                 if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(TXTLOCK))
1088                         msyslog(LOG_ERR, "plock(TXTLOCK) error: %m");
1089 #    else       /* !TXTLOCK follows */
1090                 msyslog(LOG_ERR, "plock() - don't know what to lock!");
1091 #    endif      /* !TXTLOCK */
1092 #   endif       /* !PROCLOCK */
1093 #  endif        /* HAVE_PLOCK */
1094 # endif /* !HAVE_MLOCKALL */
1095         }
1096
1097         loop_config(LOOP_DRIFTINIT, 0);
1098         report_event(EVNT_SYSRESTART, NULL, NULL);
1099         initializing = FALSE;
1100
1101 # ifdef HAVE_DROPROOT
1102         if (droproot) {
1103
1104 #ifdef NEED_EARLY_FORK
1105                 fork_nonchroot_worker();
1106 #endif
1107
1108                 /* Drop super-user privileges and chroot now if the OS supports this */
1109
1110 #  ifdef HAVE_LINUX_CAPABILITIES
1111                 /* set flag: keep privileges accross setuid() call (we only really need cap_sys_time): */
1112                 if (prctl( PR_SET_KEEPCAPS, 1L, 0L, 0L, 0L ) == -1) {
1113                         msyslog( LOG_ERR, "prctl( PR_SET_KEEPCAPS, 1L ) failed: %m" );
1114                         exit(-1);
1115                 }
1116 #  elif HAVE_SOLARIS_PRIVS
1117                 /* Nothing to do here */
1118 #  else
1119                 /* we need a user to switch to */
1120                 if (user == NULL) {
1121                         msyslog(LOG_ERR, "Need user name to drop root privileges (see -u flag!)" );
1122                         exit(-1);
1123                 }
1124 #  endif        /* HAVE_LINUX_CAPABILITIES || HAVE_SOLARIS_PRIVS */
1125
1126                 if (user != NULL) {
1127                         if (0 == map_user())
1128                                 exit (-1);
1129                 }
1130                 if (group != NULL) {
1131                         if (0 == map_group())
1132                                 exit (-1);
1133                 }
1134
1135                 if (chrootdir ) {
1136                         /* make sure cwd is inside the jail: */
1137                         if (chdir(chrootdir)) {
1138                                 msyslog(LOG_ERR, "Cannot chdir() to `%s': %m", chrootdir);
1139                                 exit (-1);
1140                         }
1141                         if (chroot(chrootdir)) {
1142                                 msyslog(LOG_ERR, "Cannot chroot() to `%s': %m", chrootdir);
1143                                 exit (-1);
1144                         }
1145                         if (chdir("/")) {
1146                                 msyslog(LOG_ERR, "Cannot chdir() to`root after chroot(): %m");
1147                                 exit (-1);
1148                         }
1149                 }
1150 #  ifdef HAVE_SOLARIS_PRIVS
1151                 if ((lowprivs = priv_str_to_set(LOWPRIVS, ",", NULL)) == NULL) {
1152                         msyslog(LOG_ERR, "priv_str_to_set() failed:%m");
1153                         exit(-1);
1154                 }
1155                 if ((highprivs = priv_allocset()) == NULL) {
1156                         msyslog(LOG_ERR, "priv_allocset() failed:%m");
1157                         exit(-1);
1158                 }
1159                 (void) getppriv(PRIV_PERMITTED, highprivs);
1160                 (void) priv_intersect(highprivs, lowprivs);
1161                 if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1162                         msyslog(LOG_ERR, "setppriv() failed:%m");
1163                         exit(-1);
1164                 }
1165 #  endif /* HAVE_SOLARIS_PRIVS */
1166                 if (0 == set_user_group_ids())
1167                         exit(-1);
1168
1169 #  if !defined(HAVE_LINUX_CAPABILITIES) && !defined(HAVE_SOLARIS_PRIVS)
1170                 /*
1171                  * for now assume that the privilege to bind to privileged ports
1172                  * is associated with running with uid 0 - should be refined on
1173                  * ports that allow binding to NTP_PORT with uid != 0
1174                  */
1175                 disable_dynamic_updates |= (sw_uid != 0);  /* also notifies routing message listener */
1176 #  endif /* !HAVE_LINUX_CAPABILITIES && !HAVE_SOLARIS_PRIVS */
1177
1178                 if (disable_dynamic_updates && interface_interval) {
1179                         interface_interval = 0;
1180                         msyslog(LOG_INFO, "running as non-root disables dynamic interface tracking");
1181                 }
1182
1183 #  ifdef HAVE_LINUX_CAPABILITIES
1184                 {
1185                         /*
1186                          *  We may be running under non-root uid now, but we still hold full root privileges!
1187                          *  We drop all of them, except for the crucial one or two: cap_sys_time and
1188                          *  cap_net_bind_service if doing dynamic interface tracking.
1189                          */
1190                         cap_t caps;
1191                         char *captext;
1192
1193                         captext = (0 != interface_interval)
1194                                       ? "cap_sys_time,cap_net_bind_service=pe"
1195                                       : "cap_sys_time=pe";
1196                         caps = cap_from_text(captext);
1197                         if (!caps) {
1198                                 msyslog(LOG_ERR,
1199                                         "cap_from_text(%s) failed: %m",
1200                                         captext);
1201                                 exit(-1);
1202                         }
1203                         if (-1 == cap_set_proc(caps)) {
1204                                 msyslog(LOG_ERR,
1205                                         "cap_set_proc() failed to drop root privs: %m");
1206                                 exit(-1);
1207                         }
1208                         cap_free(caps);
1209                 }
1210 #  endif        /* HAVE_LINUX_CAPABILITIES */
1211 #  ifdef HAVE_SOLARIS_PRIVS
1212                 if (priv_delset(lowprivs, "proc_setid") == -1) {
1213                         msyslog(LOG_ERR, "priv_delset() failed:%m");
1214                         exit(-1);
1215                 }
1216                 if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1217                         msyslog(LOG_ERR, "setppriv() failed:%m");
1218                         exit(-1);
1219                 }
1220                 priv_freeset(lowprivs);
1221                 priv_freeset(highprivs);
1222 #  endif /* HAVE_SOLARIS_PRIVS */
1223                 root_dropped = TRUE;
1224                 fork_deferred_worker();
1225         }       /* if (droproot) */
1226 # endif /* HAVE_DROPROOT */
1227
1228 /* libssecomp sandboxing */
1229 #if defined (LIBSECCOMP) && (KERN_SECCOMP)
1230         scmp_filter_ctx ctx;
1231
1232         if ((ctx = seccomp_init(SCMP_ACT_KILL)) < 0)
1233                 msyslog(LOG_ERR, "%s: seccomp_init(SCMP_ACT_KILL) failed: %m", __func__);
1234         else {
1235                 msyslog(LOG_DEBUG, "%s: seccomp_init(SCMP_ACT_KILL) succeeded", __func__);
1236         }
1237
1238 #ifdef __x86_64__
1239 int scmp_sc[] = {
1240         SCMP_SYS(adjtimex),
1241         SCMP_SYS(bind),
1242         SCMP_SYS(brk),
1243         SCMP_SYS(chdir),
1244         SCMP_SYS(clock_gettime),
1245         SCMP_SYS(clock_settime),
1246         SCMP_SYS(close),
1247         SCMP_SYS(connect),
1248         SCMP_SYS(exit_group),
1249         SCMP_SYS(fstat),
1250         SCMP_SYS(fsync),
1251         SCMP_SYS(futex),
1252         SCMP_SYS(getitimer),
1253         SCMP_SYS(getsockname),
1254         SCMP_SYS(ioctl),
1255         SCMP_SYS(lseek),
1256         SCMP_SYS(madvise),
1257         SCMP_SYS(mmap),
1258         SCMP_SYS(munmap),
1259         SCMP_SYS(open),
1260         SCMP_SYS(poll),
1261         SCMP_SYS(read),
1262         SCMP_SYS(recvmsg),
1263         SCMP_SYS(rename),
1264         SCMP_SYS(rt_sigaction),
1265         SCMP_SYS(rt_sigprocmask),
1266         SCMP_SYS(rt_sigreturn),
1267         SCMP_SYS(select),
1268         SCMP_SYS(sendto),
1269         SCMP_SYS(setitimer),
1270         SCMP_SYS(setsid),
1271         SCMP_SYS(socket),
1272         SCMP_SYS(stat),
1273         SCMP_SYS(time),
1274         SCMP_SYS(write),
1275 };
1276 #endif
1277 #ifdef __i386__
1278 int scmp_sc[] = {
1279         SCMP_SYS(_newselect),
1280         SCMP_SYS(adjtimex),
1281         SCMP_SYS(brk),
1282         SCMP_SYS(chdir),
1283         SCMP_SYS(clock_gettime),
1284         SCMP_SYS(clock_settime),
1285         SCMP_SYS(close),
1286         SCMP_SYS(exit_group),
1287         SCMP_SYS(fsync),
1288         SCMP_SYS(futex),
1289         SCMP_SYS(getitimer),
1290         SCMP_SYS(madvise),
1291         SCMP_SYS(mmap),
1292         SCMP_SYS(mmap2),
1293         SCMP_SYS(munmap),
1294         SCMP_SYS(open),
1295         SCMP_SYS(poll),
1296         SCMP_SYS(read),
1297         SCMP_SYS(rename),
1298         SCMP_SYS(rt_sigaction),
1299         SCMP_SYS(rt_sigprocmask),
1300         SCMP_SYS(select),
1301         SCMP_SYS(setitimer),
1302         SCMP_SYS(setsid),
1303         SCMP_SYS(sigprocmask),
1304         SCMP_SYS(sigreturn),
1305         SCMP_SYS(socketcall),
1306         SCMP_SYS(stat64),
1307         SCMP_SYS(time),
1308         SCMP_SYS(write),
1309 };
1310 #endif
1311         {
1312                 int i;
1313
1314                 for (i = 0; i < COUNTOF(scmp_sc); i++) {
1315                         if (seccomp_rule_add(ctx,
1316                             SCMP_ACT_ALLOW, scmp_sc[i], 0) < 0) {
1317                                 msyslog(LOG_ERR,
1318                                     "%s: seccomp_rule_add() failed: %m",
1319                                     __func__);
1320                         }
1321                 }
1322         }
1323
1324         if (seccomp_load(ctx) < 0)
1325                 msyslog(LOG_ERR, "%s: seccomp_load() failed: %m",
1326                     __func__);
1327         else {
1328                 msyslog(LOG_DEBUG, "%s: seccomp_load() succeeded", __func__);
1329         }
1330 #endif /* LIBSECCOMP and KERN_SECCOMP */
1331
1332 #ifdef SYS_WINNT
1333         ntservice_isup();
1334 #endif
1335
1336 # ifdef HAVE_IO_COMPLETION_PORT
1337
1338         for (;;) {
1339 #if !defined(SIM) && defined(SIGDIE1)
1340                 if (signalled)
1341                         finish_safe(signo);
1342 #endif
1343                 GetReceivedBuffers();
1344 # else /* normal I/O */
1345
1346         BLOCK_IO_AND_ALARM();
1347         was_alarmed = FALSE;
1348
1349         for (;;) {
1350 #if !defined(SIM) && defined(SIGDIE1)
1351                 if (signalled)
1352                         finish_safe(signo);
1353 #endif
1354                 if (alarm_flag) {       /* alarmed? */
1355                         was_alarmed = TRUE;
1356                         alarm_flag = FALSE;
1357                 }
1358
1359                 /* collect async name/addr results */
1360                 if (!was_alarmed)
1361                     harvest_blocking_responses();
1362
1363                 if (!was_alarmed && !has_full_recv_buffer()) {
1364                         /*
1365                          * Nothing to do.  Wait for something.
1366                          */
1367                         io_handler();
1368                 }
1369
1370                 if (alarm_flag) {       /* alarmed? */
1371                         was_alarmed = TRUE;
1372                         alarm_flag = FALSE;
1373                 }
1374
1375                 if (was_alarmed) {
1376                         UNBLOCK_IO_AND_ALARM();
1377                         /*
1378                          * Out here, signals are unblocked.  Call timer routine
1379                          * to process expiry.
1380                          */
1381                         timer();
1382                         was_alarmed = FALSE;
1383                         BLOCK_IO_AND_ALARM();
1384                 }
1385
1386 # endif         /* !HAVE_IO_COMPLETION_PORT */
1387
1388 # ifdef DEBUG_TIMING
1389                 {
1390                         l_fp pts;
1391                         l_fp tsa, tsb;
1392                         int bufcount = 0;
1393
1394                         get_systime(&pts);
1395                         tsa = pts;
1396 # endif
1397                         rbuf = get_full_recv_buffer();
1398                         while (rbuf != NULL) {
1399                                 if (alarm_flag) {
1400                                         was_alarmed = TRUE;
1401                                         alarm_flag = FALSE;
1402                                 }
1403                                 UNBLOCK_IO_AND_ALARM();
1404
1405                                 if (was_alarmed) {
1406                                         /* avoid timer starvation during lengthy I/O handling */
1407                                         timer();
1408                                         was_alarmed = FALSE;
1409                                 }
1410
1411                                 /*
1412                                  * Call the data procedure to handle each received
1413                                  * packet.
1414                                  */
1415                                 if (rbuf->receiver != NULL) {
1416 # ifdef DEBUG_TIMING
1417                                         l_fp dts = pts;
1418
1419                                         L_SUB(&dts, &rbuf->recv_time);
1420                                         DPRINTF(2, ("processing timestamp delta %s (with prec. fuzz)\n", lfptoa(&dts, 9)));
1421                                         collect_timing(rbuf, "buffer processing delay", 1, &dts);
1422                                         bufcount++;
1423 # endif
1424                                         (*rbuf->receiver)(rbuf);
1425                                 } else {
1426                                         msyslog(LOG_ERR, "fatal: receive buffer callback NULL");
1427                                         abort();
1428                                 }
1429
1430                                 BLOCK_IO_AND_ALARM();
1431                                 freerecvbuf(rbuf);
1432                                 rbuf = get_full_recv_buffer();
1433                         }
1434 # ifdef DEBUG_TIMING
1435                         get_systime(&tsb);
1436                         L_SUB(&tsb, &tsa);
1437                         if (bufcount) {
1438                                 collect_timing(NULL, "processing", bufcount, &tsb);
1439                                 DPRINTF(2, ("processing time for %d buffers %s\n", bufcount, lfptoa(&tsb, 9)));
1440                         }
1441                 }
1442 # endif
1443
1444                 /*
1445                  * Go around again
1446                  */
1447
1448 # ifdef HAVE_DNSREGISTRATION
1449                 if (mdnsreg && (current_time - mdnsreg ) > 60 && mdnstries && sys_leap != LEAP_NOTINSYNC) {
1450                         mdnsreg = current_time;
1451                         msyslog(LOG_INFO, "Attempting to register mDNS");
1452                         if ( DNSServiceRegister (&mdns, 0, 0, NULL, "_ntp._udp", NULL, NULL,
1453                             htons(NTP_PORT), 0, NULL, NULL, NULL) != kDNSServiceErr_NoError ) {
1454                                 if (!--mdnstries) {
1455                                         msyslog(LOG_ERR, "Unable to register mDNS, giving up.");
1456                                 } else {
1457                                         msyslog(LOG_INFO, "Unable to register mDNS, will try later.");
1458                                 }
1459                         } else {
1460                                 msyslog(LOG_INFO, "mDNS service registered.");
1461                                 mdnsreg = FALSE;
1462                         }
1463                 }
1464 # endif /* HAVE_DNSREGISTRATION */
1465
1466         }
1467         UNBLOCK_IO_AND_ALARM();
1468         return 1;
1469 }
1470 #endif  /* !SIM */
1471
1472
1473 #if !defined(SIM) && defined(SIGDIE1)
1474 /*
1475  * finish - exit gracefully
1476  */
1477 static void
1478 finish_safe(
1479         int     sig
1480         )
1481 {
1482         const char *sig_desc;
1483
1484         sig_desc = NULL;
1485 #ifdef HAVE_STRSIGNAL
1486         sig_desc = strsignal(sig);
1487 #endif
1488         if (sig_desc == NULL)
1489                 sig_desc = "";
1490         msyslog(LOG_NOTICE, "%s exiting on signal %d (%s)", progname,
1491                 sig, sig_desc);
1492         /* See Bug 2513 and Bug 2522 re the unlink of PIDFILE */
1493 # ifdef HAVE_DNSREGISTRATION
1494         if (mdns != NULL)
1495                 DNSServiceRefDeallocate(mdns);
1496 # endif
1497         peer_cleanup();
1498         exit(0);
1499 }
1500
1501 static RETSIGTYPE
1502 finish(
1503         int     sig
1504         )
1505 {
1506         signalled = 1;
1507         signo = sig;
1508 }
1509
1510 #endif  /* !SIM && SIGDIE1 */
1511
1512
1513 #ifndef SIM
1514 /*
1515  * wait_child_sync_if - implements parent side of -w/--wait-sync
1516  */
1517 # ifdef HAVE_WORKING_FORK
1518 static int
1519 wait_child_sync_if(
1520         int     pipe_read_fd,
1521         long    wait_sync
1522         )
1523 {
1524         int     rc;
1525         int     exit_code;
1526         time_t  wait_end_time;
1527         time_t  cur_time;
1528         time_t  wait_rem;
1529         fd_set  readset;
1530         struct timeval wtimeout;
1531
1532         if (0 == wait_sync)
1533                 return 0;
1534
1535         /* waitsync_fd_to_close used solely by child */
1536         close(waitsync_fd_to_close);
1537         wait_end_time = time(NULL) + wait_sync;
1538         do {
1539                 cur_time = time(NULL);
1540                 wait_rem = (wait_end_time > cur_time)
1541                                 ? (wait_end_time - cur_time)
1542                                 : 0;
1543                 wtimeout.tv_sec = wait_rem;
1544                 wtimeout.tv_usec = 0;
1545                 FD_ZERO(&readset);
1546                 FD_SET(pipe_read_fd, &readset);
1547                 rc = select(pipe_read_fd + 1, &readset, NULL, NULL,
1548                             &wtimeout);
1549                 if (-1 == rc) {
1550                         if (EINTR == errno)
1551                                 continue;
1552                         exit_code = (errno) ? errno : -1;
1553                         msyslog(LOG_ERR,
1554                                 "--wait-sync select failed: %m");
1555                         return exit_code;
1556                 }
1557                 if (0 == rc) {
1558                         /*
1559                          * select() indicated a timeout, but in case
1560                          * its timeouts are affected by a step of the
1561                          * system clock, select() again with a zero
1562                          * timeout to confirm.
1563                          */
1564                         FD_ZERO(&readset);
1565                         FD_SET(pipe_read_fd, &readset);
1566                         wtimeout.tv_sec = 0;
1567                         wtimeout.tv_usec = 0;
1568                         rc = select(pipe_read_fd + 1, &readset, NULL,
1569                                     NULL, &wtimeout);
1570                         if (0 == rc)    /* select() timeout */
1571                                 break;
1572                         else            /* readable */
1573                                 return 0;
1574                 } else                  /* readable */
1575                         return 0;
1576         } while (wait_rem > 0);
1577
1578         fprintf(stderr, "%s: -w/--wait-sync %ld timed out.\n",
1579                 progname, wait_sync);
1580         return ETIMEDOUT;
1581 }
1582 # endif /* HAVE_WORKING_FORK */
1583
1584
1585 /*
1586  * assertion_failed - Redirect assertion failures to msyslog().
1587  */
1588 static void
1589 assertion_failed(
1590         const char *file,
1591         int line,
1592         isc_assertiontype_t type,
1593         const char *cond
1594         )
1595 {
1596         isc_assertion_setcallback(NULL);    /* Avoid recursion */
1597
1598         msyslog(LOG_ERR, "%s:%d: %s(%s) failed",
1599                 file, line, isc_assertion_typetotext(type), cond);
1600         msyslog(LOG_ERR, "exiting (due to assertion failure)");
1601
1602 #if defined(DEBUG) && defined(SYS_WINNT)
1603         if (debug)
1604                 DebugBreak();
1605 #endif
1606
1607         abort();
1608 }
1609
1610
1611 /*
1612  * library_fatal_error - Handle fatal errors from our libraries.
1613  */
1614 static void
1615 library_fatal_error(
1616         const char *file,
1617         int line,
1618         const char *format,
1619         va_list args
1620         )
1621 {
1622         char errbuf[256];
1623
1624         isc_error_setfatal(NULL);  /* Avoid recursion */
1625
1626         msyslog(LOG_ERR, "%s:%d: fatal error:", file, line);
1627         vsnprintf(errbuf, sizeof(errbuf), format, args);
1628         msyslog(LOG_ERR, "%s", errbuf);
1629         msyslog(LOG_ERR, "exiting (due to fatal error in library)");
1630
1631 #if defined(DEBUG) && defined(SYS_WINNT)
1632         if (debug)
1633                 DebugBreak();
1634 #endif
1635
1636         abort();
1637 }
1638
1639
1640 /*
1641  * library_unexpected_error - Handle non fatal errors from our libraries.
1642  */
1643 # define MAX_UNEXPECTED_ERRORS 100
1644 int unexpected_error_cnt = 0;
1645 static void
1646 library_unexpected_error(
1647         const char *file,
1648         int line,
1649         const char *format,
1650         va_list args
1651         )
1652 {
1653         char errbuf[256];
1654
1655         if (unexpected_error_cnt >= MAX_UNEXPECTED_ERRORS)
1656                 return; /* avoid clutter in log */
1657
1658         msyslog(LOG_ERR, "%s:%d: unexpected error:", file, line);
1659         vsnprintf(errbuf, sizeof(errbuf), format, args);
1660         msyslog(LOG_ERR, "%s", errbuf);
1661
1662         if (++unexpected_error_cnt == MAX_UNEXPECTED_ERRORS)
1663                 msyslog(LOG_ERR, "Too many errors.  Shutting up.");
1664
1665 }
1666 #endif  /* !SIM */
1667
1668 #if !defined(SIM) && !defined(SYS_WINNT)
1669 # ifdef DEBUG
1670
1671 /*
1672  * moredebug - increase debugging verbosity
1673  */
1674 static RETSIGTYPE
1675 moredebug(
1676         int sig
1677         )
1678 {
1679         int saved_errno = errno;
1680
1681         if (debug < 255)
1682         {
1683                 debug++;
1684                 msyslog(LOG_DEBUG, "debug raised to %d", debug);
1685         }
1686         errno = saved_errno;
1687 }
1688
1689
1690 /*
1691  * lessdebug - decrease debugging verbosity
1692  */
1693 static RETSIGTYPE
1694 lessdebug(
1695         int sig
1696         )
1697 {
1698         int saved_errno = errno;
1699
1700         if (debug > 0)
1701         {
1702                 debug--;
1703                 msyslog(LOG_DEBUG, "debug lowered to %d", debug);
1704         }
1705         errno = saved_errno;
1706 }
1707
1708 # else  /* !DEBUG follows */
1709
1710
1711 /*
1712  * no_debug - We don't do the debug here.
1713  */
1714 static RETSIGTYPE
1715 no_debug(
1716         int sig
1717         )
1718 {
1719         int saved_errno = errno;
1720
1721         msyslog(LOG_DEBUG, "ntpd not compiled for debugging (signal %d)", sig);
1722         errno = saved_errno;
1723 }
1724 # endif /* !DEBUG */
1725 #endif  /* !SIM && !SYS_WINNT */