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 _AIX
 108 # include <ulimit.h>
 109 #endif /* _AIX */
 110
 111 #ifdef SCO5_CLOCK
 112 # include <sys/ci/ciioctl.h>
 113 #endif
 114
 115 #ifdef HAVE_DROPROOT
 116 # include <ctype.h>
 117 # include <grp.h>
 118 # include <pwd.h>
 119 #ifdef HAVE_LINUX_CAPABILITIES
 120 # include <sys/capability.h>
 121 # include <sys/prctl.h>
 122 #endif /* HAVE_LINUX_CAPABILITIES */
 123 #if defined(HAVE_PRIV_H) && defined(HAVE_SOLARIS_PRIVS)
 124 # include <priv.h>
 125 #endif /* HAVE_PRIV_H */
 126 #if defined(HAVE_TRUSTEDBSD_MAC)
 127 # include <sys/mac.h>
 128 #endif /* HAVE_TRUSTEDBSD_MAC */
 129 #endif /* HAVE_DROPROOT */
 130
 131 #if defined (LIBSECCOMP) && (KERN_SECCOMP)
 132 /* # include <sys/types.h> */
 133 # include <sys/resource.h>
 134 # include <seccomp.h>
 135 #endif /* LIBSECCOMP and KERN_SECCOMP */
 136
 137 #ifdef HAVE_DNSREGISTRATION
 138 # include <dns_sd.h>
 139 DNSServiceRef mdns;
 140 #endif
 141
 142 #ifdef HAVE_SETPGRP_0
 143 # define ntp_setpgrp(x, y)      setpgrp()
 144 #else
 145 # define ntp_setpgrp(x, y)      setpgrp(x, y)
 146 #endif
 147
 148 #ifdef HAVE_SOLARIS_PRIVS
 149 # define LOWPRIVS "basic,sys_time,net_privaddr,proc_setid,!proc_info,!proc_session,!proc_exec"
 150 static priv_set_t *lowprivs = NULL;
 151 static priv_set_t *highprivs = NULL;
 152 #endif /* HAVE_SOLARIS_PRIVS */
 153 /*
 154  * Scheduling priority we run at
 155  */
 156 #define NTPD_PRIO       (-12)
 157
 158 int priority_done = 2;          /* 0 - Set priority */
 159                                 /* 1 - priority is OK where it is */
 160                                 /* 2 - Don't set priority */
 161                                 /* 1 and 2 are pretty much the same */
 162
 163 int listen_to_virtual_ips = TRUE;
 164
 165 /*
 166  * No-fork flag.  If set, we do not become a background daemon.
 167  */
 168 int nofork;                     /* Fork by default */
 169
 170 #ifdef HAVE_DNSREGISTRATION
 171 /*
 172  * mDNS registration flag. If set, we attempt to register with the mDNS system, but only
 173  * after we have synched the first time. If the attempt fails, then try again once per
 174  * minute for up to 5 times. After all, we may be starting before mDNS.
 175  */
 176 int mdnsreg = FALSE;
 177 int mdnstries = 5;
 178 #endif  /* HAVE_DNSREGISTRATION */
 179
 180 #ifdef HAVE_DROPROOT
 181 int droproot;
 182 int root_dropped;
 183 char *user;             /* User to switch to */
 184 char *group;            /* group to switch to */
 185 const char *chrootdir;  /* directory to chroot to */
 186 uid_t sw_uid;
 187 gid_t sw_gid;
 188 char *endp;
 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
 530 /*
 531  * Main program.  Initialize us, disconnect us from the tty if necessary,
 532  * and loop waiting for I/O and/or timer expiries.
 533  */
 534 #ifndef SIM
 535 int
 536 ntpdmain(
 537         int argc,
 538         char *argv[]
 539         )
 540 {
 541         l_fp            now;
 542         struct recvbuf *rbuf;
 543         const char *    logfilename;
 544 # ifdef HAVE_UMASK
 545         mode_t          uv;
 546 # endif
 547 # if defined(HAVE_GETUID) && !defined(MPE) /* MPE lacks the concept of root */
 548         uid_t           uid;
 549 # endif
 550 # if defined(HAVE_WORKING_FORK)
 551         long            wait_sync = 0;
 552         int             pipe_fds[2];
 553         int             rc;
 554         int             exit_code;
 555 #  ifdef _AIX
 556         struct sigaction sa;
 557 #  endif
 558 #  if !defined(HAVE_SETSID) && !defined (HAVE_SETPGID) && defined(TIOCNOTTY)
 559         int             fid;
 560 #  endif
 561 # endif /* HAVE_WORKING_FORK*/
 562 # ifdef SCO5_CLOCK
 563         int             fd;
 564         int             zero;
 565 # endif
 566
 567 # ifdef NEED_PTHREAD_WARMUP
 568         my_pthread_warmup();
 569 # endif
 570
 571 # ifdef HAVE_UMASK
 572         uv = umask(0);
 573         if (uv)
 574                 umask(uv);
 575         else
 576                 umask(022);
 577 # endif
 578         saved_argc = argc;
 579         saved_argv = argv;
 580         progname = argv[0];
 581         initializing = TRUE;            /* mark that we are initializing */
 582         parse_cmdline_opts(&argc, &argv);
 583 # ifdef DEBUG
 584         debug = OPT_VALUE_SET_DEBUG_LEVEL;
 585 #  ifdef HAVE_SETLINEBUF
 586         setlinebuf(stdout);
 587 #  endif
 588 # endif
 589
 590         if (HAVE_OPT(NOFORK) || HAVE_OPT(QUIT)
 591 # ifdef DEBUG
 592             || debug
 593 # endif
 594             || HAVE_OPT(SAVECONFIGQUIT))
 595                 nofork = TRUE;
 596
 597         init_logging(progname, NLOG_SYNCMASK, TRUE);
 598         /* honor -l/--logfile option to log to a file */
 599         if (HAVE_OPT(LOGFILE)) {
 600                 logfilename = OPT_ARG(LOGFILE);
 601                 syslogit = FALSE;
 602                 change_logfile(logfilename, FALSE);
 603         } else {
 604                 logfilename = NULL;
 605                 if (nofork)
 606                         msyslog_term = TRUE;
 607                 if (HAVE_OPT(SAVECONFIGQUIT))
 608                         syslogit = FALSE;
 609         }
 610         msyslog(LOG_NOTICE, "%s: Starting", Version);
 611
 612         {
 613                 int i;
 614                 char buf[1024]; /* Secret knowledge of msyslog buf length */
 615                 char *cp = buf;
 616
 617                 /* Note that every arg has an initial space character */
 618                 snprintf(cp, sizeof(buf), "Command line:");
 619                 cp += strlen(cp);
 620
 621                 for (i = 0; i < saved_argc ; ++i) {
 622                         snprintf(cp, sizeof(buf) - (cp - buf),
 623                                 " %s", saved_argv[i]);
 624                         cp += strlen(cp);
 625                 }
 626                 msyslog(LOG_INFO, "%s", buf);
 627         }
 628
 629         /*
 630          * Install trap handlers to log errors and assertion failures.
 631          * Default handlers print to stderr which doesn't work if detached.
 632          */
 633         isc_assertion_setcallback(assertion_failed);
 634         isc_error_setfatal(library_fatal_error);
 635         isc_error_setunexpected(library_unexpected_error);
 636
 637         /* MPE lacks the concept of root */
 638 # if defined(HAVE_GETUID) && !defined(MPE)
 639         uid = getuid();
 640         if (uid && !HAVE_OPT( SAVECONFIGQUIT )
 641 #  if defined(HAVE_TRUSTEDBSD_MAC)
 642             /* We can run as non-root if the mac_ntpd policy is enabled. */
 643             && mac_is_present("ntpd") != 1
 644 #  endif
 645             ) {
 646                 msyslog_term = TRUE;
 647                 msyslog(LOG_ERR,
 648                         "must be run as root, not uid %ld", (long)uid);
 649                 exit(1);
 650         }
 651 # endif
 652
 653 /*
 654  * Enable the Multi-Media Timer for Windows?
 655  */
 656 # ifdef SYS_WINNT
 657         if (HAVE_OPT( MODIFYMMTIMER ))
 658                 set_mm_timer(MM_TIMER_HIRES);
 659 # endif
 660
 661 #ifdef HAVE_DNSREGISTRATION
 662 /*
 663  * Enable mDNS registrations?
 664  */
 665         if (HAVE_OPT( MDNS )) {
 666                 mdnsreg = TRUE;
 667         }
 668 #endif  /* HAVE_DNSREGISTRATION */
 669
 670         if (HAVE_OPT( NOVIRTUALIPS ))
 671                 listen_to_virtual_ips = 0;
 672
 673         /*
 674          * --interface, listen on specified interfaces
 675          */
 676         if (HAVE_OPT( INTERFACE )) {
 677                 int             ifacect = STACKCT_OPT( INTERFACE );
 678                 const char**    ifaces  = STACKLST_OPT( INTERFACE );
 679                 sockaddr_u      addr;
 680
 681                 while (ifacect-- > 0) {
 682                         add_nic_rule(
 683                                 is_ip_address(*ifaces, AF_UNSPEC, &addr)
 684                                         ? MATCH_IFADDR
 685                                         : MATCH_IFNAME,
 686                                 *ifaces, -1, ACTION_LISTEN);
 687                         ifaces++;
 688                 }
 689         }
 690
 691         if (HAVE_OPT( NICE ))
 692                 priority_done = 0;
 693
 694 # ifdef HAVE_SCHED_SETSCHEDULER
 695         if (HAVE_OPT( PRIORITY )) {
 696                 config_priority = OPT_VALUE_PRIORITY;
 697                 config_priority_override = 1;
 698                 priority_done = 0;
 699         }
 700 # endif
 701
 702 # ifdef HAVE_WORKING_FORK
 703         /* make sure the FDs are initialised */
 704         pipe_fds[0] = -1;
 705         pipe_fds[1] = -1;
 706         do {                                    /* 'loop' once */
 707                 if (!HAVE_OPT( WAIT_SYNC ))
 708                         break;
 709                 wait_sync = OPT_VALUE_WAIT_SYNC;
 710                 if (wait_sync <= 0) {
 711                         wait_sync = 0;
 712                         break;
 713                 }
 714                 /* -w requires a fork() even with debug > 0 */
 715                 nofork = FALSE;
 716                 if (pipe(pipe_fds)) {
 717                         exit_code = (errno) ? errno : -1;
 718                         msyslog(LOG_ERR,
 719                                 "Pipe creation failed for --wait-sync: %m");
 720                         exit(exit_code);
 721                 }
 722                 waitsync_fd_to_close = pipe_fds[1];
 723         } while (0);                            /* 'loop' once */
 724 # endif /* HAVE_WORKING_FORK */
 725
 726         init_lib();
 727 # ifdef SYS_WINNT
 728         /*
 729          * Start interpolation thread, must occur before first
 730          * get_systime()
 731          */
 732         init_winnt_time();
 733 # endif
 734         /*
 735          * Initialize random generator and public key pair
 736          */
 737         get_systime(&now);
 738
 739         ntp_srandom((int)(now.l_i * now.l_uf));
 740
 741         /*
 742          * Detach us from the terminal.  May need an #ifndef GIZMO.
 743          */
 744         if (!nofork) {
 745
 746 # ifdef HAVE_WORKING_FORK
 747                 rc = fork();
 748                 if (-1 == rc) {
 749                         exit_code = (errno) ? errno : -1;
 750                         msyslog(LOG_ERR, "fork: %m");
 751                         exit(exit_code);
 752                 }
 753                 if (rc > 0) {
 754                         /* parent */
 755                         exit_code = wait_child_sync_if(pipe_fds[0],
 756                                                        wait_sync);
 757                         exit(exit_code);
 758                 }
 759
 760                 /*
 761                  * child/daemon
 762                  * close all open files excepting waitsync_fd_to_close.
 763                  * msyslog() unreliable until after init_logging().
 764                  */
 765                 closelog();
 766                 if (syslog_file != NULL) {
 767                         fclose(syslog_file);
 768                         syslog_file = NULL;
 769                         syslogit = TRUE;
 770                 }
 771                 close_all_except(waitsync_fd_to_close);
 772                 INSIST(0 == open("/dev/null", 0) && 1 == dup2(0, 1) \
 773                         && 2 == dup2(0, 2));
 774
 775                 init_logging(progname, 0, TRUE);
 776                 /* we lost our logfile (if any) daemonizing */
 777                 setup_logfile(logfilename);
 778
 779 #  ifdef SYS_DOMAINOS
 780                 {
 781                         uid_$t puid;
 782                         status_$t st;
 783
 784                         proc2_$who_am_i(&puid);
 785                         proc2_$make_server(&puid, &st);
 786                 }
 787 #  endif        /* SYS_DOMAINOS */
 788 #  ifdef HAVE_SETSID
 789                 if (setsid() == (pid_t)-1)
 790                         msyslog(LOG_ERR, "setsid(): %m");
 791 #  elif defined(HAVE_SETPGID)
 792                 if (setpgid(0, 0) == -1)
 793                         msyslog(LOG_ERR, "setpgid(): %m");
 794 #  else         /* !HAVE_SETSID && !HAVE_SETPGID follows */
 795 #   ifdef TIOCNOTTY
 796                 fid = open("/dev/tty", 2);
 797                 if (fid >= 0) {
 798                         ioctl(fid, (u_long)TIOCNOTTY, NULL);
 799                         close(fid);
 800                 }
 801 #   endif       /* TIOCNOTTY */
 802                 ntp_setpgrp(0, getpid());
 803 #  endif        /* !HAVE_SETSID && !HAVE_SETPGID */
 804 #  ifdef _AIX
 805                 /* Don't get killed by low-on-memory signal. */
 806                 sa.sa_handler = catch_danger;
 807                 sigemptyset(&sa.sa_mask);
 808                 sa.sa_flags = SA_RESTART;
 809                 sigaction(SIGDANGER, &sa, NULL);
 810 #  endif        /* _AIX */
 811 # endif         /* HAVE_WORKING_FORK */
 812         }
 813
 814 # ifdef SCO5_CLOCK
 815         /*
 816          * SCO OpenServer's system clock offers much more precise timekeeping
 817          * on the base CPU than the other CPUs (for multiprocessor systems),
 818          * so we must lock to the base CPU.
 819          */
 820         fd = open("/dev/at1", O_RDONLY);
 821         if (fd >= 0) {
 822                 zero = 0;
 823                 if (ioctl(fd, ACPU_LOCK, &zero) < 0)
 824                         msyslog(LOG_ERR, "cannot lock to base CPU: %m");
 825                 close(fd);
 826         }
 827 # endif
 828
 829         /* Setup stack size in preparation for locking pages in memory. */
 830 # if defined(HAVE_MLOCKALL)
 831 #  ifdef HAVE_SETRLIMIT
 832         ntp_rlimit(RLIMIT_STACK, DFLT_RLIMIT_STACK * 4096, 4096, "4k");
 833 #   ifdef RLIMIT_MEMLOCK
 834         /*
 835          * The default RLIMIT_MEMLOCK is very low on Linux systems.
 836          * Unless we increase this limit malloc calls are likely to
 837          * fail if we drop root privilege.  To be useful the value
 838          * has to be larger than the largest ntpd resident set size.
 839          */
 840         ntp_rlimit(RLIMIT_MEMLOCK, DFLT_RLIMIT_MEMLOCK * 1024 * 1024, 1024 * 1024, "MB");
 841 #   endif       /* RLIMIT_MEMLOCK */
 842 #  endif        /* HAVE_SETRLIMIT */
 843 # else  /* !HAVE_MLOCKALL follows */
 844 #  ifdef HAVE_PLOCK
 845 #   ifdef PROCLOCK
 846 #    ifdef _AIX
 847         /*
 848          * set the stack limit for AIX for plock().
 849          * see get_aix_stack() for more info.
 850          */
 851         if (ulimit(SET_STACKLIM, (get_aix_stack() - 8 * 4096)) < 0)
 852                 msyslog(LOG_ERR,
 853                         "Cannot adjust stack limit for plock: %m");
 854 #    endif      /* _AIX */
 855 #   endif       /* PROCLOCK */
 856 #  endif        /* HAVE_PLOCK */
 857 # endif /* !HAVE_MLOCKALL */
 858
 859         /*
 860          * Set up signals we pay attention to locally.
 861          */
 862 # ifdef SIGDIE1
 863         signal_no_reset(SIGDIE1, finish);
 864         signal_no_reset(SIGDIE2, finish);
 865         signal_no_reset(SIGDIE3, finish);
 866         signal_no_reset(SIGDIE4, finish);
 867 # endif
 868 # ifdef SIGBUS
 869         signal_no_reset(SIGBUS, finish);
 870 # endif
 871
 872 # if !defined(SYS_WINNT) && !defined(VMS)
 873 #  ifdef DEBUG
 874         (void) signal_no_reset(MOREDEBUGSIG, moredebug);
 875         (void) signal_no_reset(LESSDEBUGSIG, lessdebug);
 876 #  else
 877         (void) signal_no_reset(MOREDEBUGSIG, no_debug);
 878         (void) signal_no_reset(LESSDEBUGSIG, no_debug);
 879 #  endif        /* DEBUG */
 880 # endif /* !SYS_WINNT && !VMS */
 881
 882         /*
 883          * Set up signals we should never pay attention to.
 884          */
 885 # ifdef SIGPIPE
 886         signal_no_reset(SIGPIPE, SIG_IGN);
 887 # endif
 888
 889         /*
 890          * Call the init_ routines to initialize the data structures.
 891          *
 892          * Exactly what command-line options are we expecting here?
 893          */
 894         INIT_SSL();
 895         init_auth();
 896         init_util();
 897         init_restrict();
 898         init_mon();
 899         init_timer();
 900         init_request();
 901         init_control();
 902         init_peer();
 903 # ifdef REFCLOCK
 904         init_refclock();
 905 # endif
 906         set_process_priority();
 907         init_proto();           /* Call at high priority */
 908         init_io();
 909         init_loopfilter();
 910         mon_start(MON_ON);      /* monitor on by default now      */
 911                                 /* turn off in config if unwanted */
 912
 913         /*
 914          * Get the configuration.  This is done in a separate module
 915          * since this will definitely be different for the gizmo board.
 916          */
 917         getconfig(argc, argv);
 918
 919         if (-1 == cur_memlock) {
 920 # if defined(HAVE_MLOCKALL)
 921                 /*
 922                  * lock the process into memory
 923                  */
 924                 if (   !HAVE_OPT(SAVECONFIGQUIT)
 925 #  ifdef RLIMIT_MEMLOCK
 926                     && -1 != DFLT_RLIMIT_MEMLOCK
 927 #  endif
 928                     && 0 != mlockall(MCL_CURRENT|MCL_FUTURE))
 929                         msyslog(LOG_ERR, "mlockall(): %m");
 930 # else  /* !HAVE_MLOCKALL follows */
 931 #  ifdef HAVE_PLOCK
 932 #   ifdef PROCLOCK
 933                 /*
 934                  * lock the process into memory
 935                  */
 936                 if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(PROCLOCK))
 937                         msyslog(LOG_ERR, "plock(PROCLOCK): %m");
 938 #   else        /* !PROCLOCK follows  */
 939 #    ifdef TXTLOCK
 940                 /*
 941                  * Lock text into ram
 942                  */
 943                 if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(TXTLOCK))
 944                         msyslog(LOG_ERR, "plock(TXTLOCK) error: %m");
 945 #    else       /* !TXTLOCK follows */
 946                 msyslog(LOG_ERR, "plock() - don't know what to lock!");
 947 #    endif      /* !TXTLOCK */
 948 #   endif       /* !PROCLOCK */
 949 #  endif        /* HAVE_PLOCK */
 950 # endif /* !HAVE_MLOCKALL */
 951         }
 952
 953         loop_config(LOOP_DRIFTINIT, 0);
 954         report_event(EVNT_SYSRESTART, NULL, NULL);
 955         initializing = FALSE;
 956
 957 # ifdef HAVE_DROPROOT
 958         if (droproot) {
 959
 960 #ifdef NEED_EARLY_FORK
 961                 fork_nonchroot_worker();
 962 #endif
 963
 964                 /* Drop super-user privileges and chroot now if the OS supports this */
 965
 966 #  ifdef HAVE_LINUX_CAPABILITIES
 967                 /* set flag: keep privileges accross setuid() call (we only really need cap_sys_time): */
 968                 if (prctl( PR_SET_KEEPCAPS, 1L, 0L, 0L, 0L ) == -1) {
 969                         msyslog( LOG_ERR, "prctl( PR_SET_KEEPCAPS, 1L ) failed: %m" );
 970                         exit(-1);
 971                 }
 972 #  elif HAVE_SOLARIS_PRIVS
 973                 /* Nothing to do here */
 974 #  else
 975                 /* we need a user to switch to */
 976                 if (user == NULL) {
 977                         msyslog(LOG_ERR, "Need user name to drop root privileges (see -u flag!)" );
 978                         exit(-1);
 979                 }
 980 #  endif        /* HAVE_LINUX_CAPABILITIES || HAVE_SOLARIS_PRIVS */
 981
 982                 if (user != NULL) {
 983                         if (isdigit((unsigned char)*user)) {
 984                                 sw_uid = (uid_t)strtoul(user, &endp, 0);
 985                                 if (*endp != '\0')
 986                                         goto getuser;
 987
 988                                 if ((pw = getpwuid(sw_uid)) != NULL) {
 989                                         free(user);
 990                                         user = estrdup(pw->pw_name);
 991                                         sw_gid = pw->pw_gid;
 992                                 } else {
 993                                         errno = 0;
 994                                         msyslog(LOG_ERR, "Cannot find user ID %s", user);
 995                                         exit (-1);
 996                                 }
 997
 998                         } else {
 999 getuser:
1000                                 errno = 0;
1001                                 if ((pw = getpwnam(user)) != NULL) {
1002                                         sw_uid = pw->pw_uid;
1003                                         sw_gid = pw->pw_gid;
1004                                 } else {
1005                                         if (errno)
1006                                                 msyslog(LOG_ERR, "getpwnam(%s) failed: %m", user);
1007                                         else
1008                                                 msyslog(LOG_ERR, "Cannot find user `%s'", user);
1009                                         exit (-1);
1010                                 }
1011                         }
1012                 }
1013                 if (group != NULL) {
1014                         if (isdigit((unsigned char)*group)) {
1015                                 sw_gid = (gid_t)strtoul(group, &endp, 0);
1016                                 if (*endp != '\0')
1017                                         goto getgroup;
1018                         } else {
1019 getgroup:
1020                                 if ((gr = getgrnam(group)) != NULL) {
1021                                         sw_gid = gr->gr_gid;
1022                                 } else {
1023                                         errno = 0;
1024                                         msyslog(LOG_ERR, "Cannot find group `%s'", group);
1025                                         exit (-1);
1026                                 }
1027                         }
1028                 }
1029
1030                 if (chrootdir ) {
1031                         /* make sure cwd is inside the jail: */
1032                         if (chdir(chrootdir)) {
1033                                 msyslog(LOG_ERR, "Cannot chdir() to `%s': %m", chrootdir);
1034                                 exit (-1);
1035                         }
1036                         if (chroot(chrootdir)) {
1037                                 msyslog(LOG_ERR, "Cannot chroot() to `%s': %m", chrootdir);
1038                                 exit (-1);
1039                         }
1040                         if (chdir("/")) {
1041                                 msyslog(LOG_ERR, "Cannot chdir() to`root after chroot(): %m");
1042                                 exit (-1);
1043                         }
1044                 }
1045 #  ifdef HAVE_SOLARIS_PRIVS
1046                 if ((lowprivs = priv_str_to_set(LOWPRIVS, ",", NULL)) == NULL) {
1047                         msyslog(LOG_ERR, "priv_str_to_set() failed:%m");
1048                         exit(-1);
1049                 }
1050                 if ((highprivs = priv_allocset()) == NULL) {
1051                         msyslog(LOG_ERR, "priv_allocset() failed:%m");
1052                         exit(-1);
1053                 }
1054                 (void) getppriv(PRIV_PERMITTED, highprivs);
1055                 (void) priv_intersect(highprivs, lowprivs);
1056                 if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1057                         msyslog(LOG_ERR, "setppriv() failed:%m");
1058                         exit(-1);
1059                 }
1060 #  endif /* HAVE_SOLARIS_PRIVS */
1061                 if (user && initgroups(user, sw_gid)) {
1062                         msyslog(LOG_ERR, "Cannot initgroups() to user `%s': %m", user);
1063                         exit (-1);
1064                 }
1065                 if (group && setgid(sw_gid)) {
1066                         msyslog(LOG_ERR, "Cannot setgid() to group `%s': %m", group);
1067                         exit (-1);
1068                 }
1069                 if (group && setegid(sw_gid)) {
1070                         msyslog(LOG_ERR, "Cannot setegid() to group `%s': %m", group);
1071                         exit (-1);
1072                 }
1073                 if (group) {
1074                         if (0 != setgroups(1, &sw_gid)) {
1075                                 msyslog(LOG_ERR, "setgroups(1, %d) failed: %m", sw_gid);
1076                                 exit (-1);
1077                         }
1078                 }
1079                 else if (pw)
1080                         if (0 != initgroups(pw->pw_name, pw->pw_gid)) {
1081                                 msyslog(LOG_ERR, "initgroups(<%s>, %d) filed: %m", pw->pw_name, pw->pw_gid);
1082                                 exit (-1);
1083                         }
1084                 if (user && setuid(sw_uid)) {
1085                         msyslog(LOG_ERR, "Cannot setuid() to user `%s': %m", user);
1086                         exit (-1);
1087                 }
1088                 if (user && seteuid(sw_uid)) {
1089                         msyslog(LOG_ERR, "Cannot seteuid() to user `%s': %m", user);
1090                         exit (-1);
1091                 }
1092
1093 #  if defined(HAVE_TRUSTEDBSD_MAC)
1094                 /*
1095                  * To manipulate system time and (re-)bind to NTP_PORT as needed
1096                  * following interface changes, we must either run as uid 0 or
1097                  * the mac_ntpd policy module must be enabled.
1098                  */
1099                 if (sw_uid != 0 && mac_is_present("ntpd") != 1) {
1100                         msyslog(LOG_ERR, "Need MAC 'ntpd' policy enabled to drop root privileges");
1101                         exit (-1);
1102                 }
1103 #  elif !defined(HAVE_LINUX_CAPABILITIES) && !defined(HAVE_SOLARIS_PRIVS)
1104                 /*
1105                  * for now assume that the privilege to bind to privileged ports
1106                  * is associated with running with uid 0 - should be refined on
1107                  * ports that allow binding to NTP_PORT with uid != 0
1108                  */
1109                 disable_dynamic_updates |= (sw_uid != 0);  /* also notifies routing message listener */
1110 #  endif /* !HAVE_LINUX_CAPABILITIES && !HAVE_SOLARIS_PRIVS */
1111
1112                 if (disable_dynamic_updates && interface_interval) {
1113                         interface_interval = 0;
1114                         msyslog(LOG_INFO, "running as non-root disables dynamic interface tracking");
1115                 }
1116
1117 #  ifdef HAVE_LINUX_CAPABILITIES
1118                 {
1119                         /*
1120                          *  We may be running under non-root uid now, but we still hold full root privileges!
1121                          *  We drop all of them, except for the crucial one or two: cap_sys_time and
1122                          *  cap_net_bind_service if doing dynamic interface tracking.
1123                          */
1124                         cap_t caps;
1125                         char *captext;
1126
1127                         captext = (0 != interface_interval)
1128                                       ? "cap_sys_time,cap_net_bind_service=pe"
1129                                       : "cap_sys_time=pe";
1130                         caps = cap_from_text(captext);
1131                         if (!caps) {
1132                                 msyslog(LOG_ERR,
1133                                         "cap_from_text(%s) failed: %m",
1134                                         captext);
1135                                 exit(-1);
1136                         }
1137                         if (-1 == cap_set_proc(caps)) {
1138                                 msyslog(LOG_ERR,
1139                                         "cap_set_proc() failed to drop root privs: %m");
1140                                 exit(-1);
1141                         }
1142                         cap_free(caps);
1143                 }
1144 #  endif        /* HAVE_LINUX_CAPABILITIES */
1145 #  ifdef HAVE_SOLARIS_PRIVS
1146                 if (priv_delset(lowprivs, "proc_setid") == -1) {
1147                         msyslog(LOG_ERR, "priv_delset() failed:%m");
1148                         exit(-1);
1149                 }
1150                 if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
1151                         msyslog(LOG_ERR, "setppriv() failed:%m");
1152                         exit(-1);
1153                 }
1154                 priv_freeset(lowprivs);
1155                 priv_freeset(highprivs);
1156 #  endif /* HAVE_SOLARIS_PRIVS */
1157                 root_dropped = TRUE;
1158                 fork_deferred_worker();
1159         }       /* if (droproot) */
1160 # endif /* HAVE_DROPROOT */
1161
1162 /* libssecomp sandboxing */
1163 #if defined (LIBSECCOMP) && (KERN_SECCOMP)
1164         scmp_filter_ctx ctx;
1165
1166         if ((ctx = seccomp_init(SCMP_ACT_KILL)) < 0)
1167                 msyslog(LOG_ERR, "%s: seccomp_init(SCMP_ACT_KILL) failed: %m", __func__);
1168         else {
1169                 msyslog(LOG_DEBUG, "%s: seccomp_init(SCMP_ACT_KILL) succeeded", __func__);
1170         }
1171
1172 #ifdef __x86_64__
1173 int scmp_sc[] = {
1174         SCMP_SYS(adjtimex),
1175         SCMP_SYS(bind),
1176         SCMP_SYS(brk),
1177         SCMP_SYS(chdir),
1178         SCMP_SYS(clock_gettime),
1179         SCMP_SYS(clock_settime),
1180         SCMP_SYS(close),
1181         SCMP_SYS(connect),
1182         SCMP_SYS(exit_group),
1183         SCMP_SYS(fstat),
1184         SCMP_SYS(fsync),
1185         SCMP_SYS(futex),
1186         SCMP_SYS(getitimer),
1187         SCMP_SYS(getsockname),
1188         SCMP_SYS(ioctl),
1189         SCMP_SYS(lseek),
1190         SCMP_SYS(madvise),
1191         SCMP_SYS(mmap),
1192         SCMP_SYS(munmap),
1193         SCMP_SYS(open),
1194         SCMP_SYS(poll),
1195         SCMP_SYS(read),
1196         SCMP_SYS(recvmsg),
1197         SCMP_SYS(rename),
1198         SCMP_SYS(rt_sigaction),
1199         SCMP_SYS(rt_sigprocmask),
1200         SCMP_SYS(rt_sigreturn),
1201         SCMP_SYS(select),
1202         SCMP_SYS(sendto),
1203         SCMP_SYS(setitimer),
1204         SCMP_SYS(setsid),
1205         SCMP_SYS(socket),
1206         SCMP_SYS(stat),
1207         SCMP_SYS(time),
1208         SCMP_SYS(write),
1209 };
1210 #endif
1211 #ifdef __i386__
1212 int scmp_sc[] = {
1213         SCMP_SYS(_newselect),
1214         SCMP_SYS(adjtimex),
1215         SCMP_SYS(brk),
1216         SCMP_SYS(chdir),
1217         SCMP_SYS(clock_gettime),
1218         SCMP_SYS(clock_settime),
1219         SCMP_SYS(close),
1220         SCMP_SYS(exit_group),
1221         SCMP_SYS(fsync),
1222         SCMP_SYS(futex),
1223         SCMP_SYS(getitimer),
1224         SCMP_SYS(madvise),
1225         SCMP_SYS(mmap),
1226         SCMP_SYS(mmap2),
1227         SCMP_SYS(munmap),
1228         SCMP_SYS(open),
1229         SCMP_SYS(poll),
1230         SCMP_SYS(read),
1231         SCMP_SYS(rename),
1232         SCMP_SYS(rt_sigaction),
1233         SCMP_SYS(rt_sigprocmask),
1234         SCMP_SYS(select),
1235         SCMP_SYS(setitimer),
1236         SCMP_SYS(setsid),
1237         SCMP_SYS(sigprocmask),
1238         SCMP_SYS(sigreturn),
1239         SCMP_SYS(socketcall),
1240         SCMP_SYS(stat64),
1241         SCMP_SYS(time),
1242         SCMP_SYS(write),
1243 };
1244 #endif
1245         {
1246                 int i;
1247
1248                 for (i = 0; i < COUNTOF(scmp_sc); i++) {
1249                         if (seccomp_rule_add(ctx,
1250                             SCMP_ACT_ALLOW, scmp_sc[i], 0) < 0) {
1251                                 msyslog(LOG_ERR,
1252                                     "%s: seccomp_rule_add() failed: %m",
1253                                     __func__);
1254                         }
1255                 }
1256         }
1257
1258         if (seccomp_load(ctx) < 0)
1259                 msyslog(LOG_ERR, "%s: seccomp_load() failed: %m",
1260                     __func__);
1261         else {
1262                 msyslog(LOG_DEBUG, "%s: seccomp_load() succeeded", __func__);
1263         }
1264 #endif /* LIBSECCOMP and KERN_SECCOMP */
1265
1266 # ifdef HAVE_IO_COMPLETION_PORT
1267
1268         for (;;) {
1269 #if !defined(SIM) && defined(SIGDIE1)
1270                 if (signalled)
1271                         finish_safe(signo);
1272 #endif
1273                 GetReceivedBuffers();
1274 # else /* normal I/O */
1275
1276         BLOCK_IO_AND_ALARM();
1277         was_alarmed = FALSE;
1278
1279         for (;;) {
1280 #if !defined(SIM) && defined(SIGDIE1)
1281                 if (signalled)
1282                         finish_safe(signo);
1283 #endif
1284                 if (alarm_flag) {       /* alarmed? */
1285                         was_alarmed = TRUE;
1286                         alarm_flag = FALSE;
1287                 }
1288
1289                 /* collect async name/addr results */
1290                 if (!was_alarmed)
1291                     harvest_blocking_responses();
1292
1293                 if (!was_alarmed && !has_full_recv_buffer()) {
1294                         /*
1295                          * Nothing to do.  Wait for something.
1296                          */
1297                         io_handler();
1298                 }
1299
1300                 if (alarm_flag) {       /* alarmed? */
1301                         was_alarmed = TRUE;
1302                         alarm_flag = FALSE;
1303                 }
1304
1305                 if (was_alarmed) {
1306                         UNBLOCK_IO_AND_ALARM();
1307                         /*
1308                          * Out here, signals are unblocked.  Call timer routine
1309                          * to process expiry.
1310                          */
1311                         timer();
1312                         was_alarmed = FALSE;
1313                         BLOCK_IO_AND_ALARM();
1314                 }
1315
1316 # endif         /* !HAVE_IO_COMPLETION_PORT */
1317
1318 # ifdef DEBUG_TIMING
1319                 {
1320                         l_fp pts;
1321                         l_fp tsa, tsb;
1322                         int bufcount = 0;
1323
1324                         get_systime(&pts);
1325                         tsa = pts;
1326 # endif
1327                         rbuf = get_full_recv_buffer();
1328                         while (rbuf != NULL) {
1329                                 if (alarm_flag) {
1330                                         was_alarmed = TRUE;
1331                                         alarm_flag = FALSE;
1332                                 }
1333                                 UNBLOCK_IO_AND_ALARM();
1334
1335                                 if (was_alarmed) {
1336                                         /* avoid timer starvation during lengthy I/O handling */
1337                                         timer();
1338                                         was_alarmed = FALSE;
1339                                 }
1340
1341                                 /*
1342                                  * Call the data procedure to handle each received
1343                                  * packet.
1344                                  */
1345                                 if (rbuf->receiver != NULL) {
1346 # ifdef DEBUG_TIMING
1347                                         l_fp dts = pts;
1348
1349                                         L_SUB(&dts, &rbuf->recv_time);
1350                                         DPRINTF(2, ("processing timestamp delta %s (with prec. fuzz)\n", lfptoa(&dts, 9)));
1351                                         collect_timing(rbuf, "buffer processing delay", 1, &dts);
1352                                         bufcount++;
1353 # endif
1354                                         (*rbuf->receiver)(rbuf);
1355                                 } else {
1356                                         msyslog(LOG_ERR, "fatal: receive buffer callback NULL");
1357                                         abort();
1358                                 }
1359
1360                                 BLOCK_IO_AND_ALARM();
1361                                 freerecvbuf(rbuf);
1362                                 rbuf = get_full_recv_buffer();
1363                         }
1364 # ifdef DEBUG_TIMING
1365                         get_systime(&tsb);
1366                         L_SUB(&tsb, &tsa);
1367                         if (bufcount) {
1368                                 collect_timing(NULL, "processing", bufcount, &tsb);
1369                                 DPRINTF(2, ("processing time for %d buffers %s\n", bufcount, lfptoa(&tsb, 9)));
1370                         }
1371                 }
1372 # endif
1373
1374                 /*
1375                  * Go around again
1376                  */
1377
1378 # ifdef HAVE_DNSREGISTRATION
1379                 if (mdnsreg && (current_time - mdnsreg ) > 60 && mdnstries && sys_leap != LEAP_NOTINSYNC) {
1380                         mdnsreg = current_time;
1381                         msyslog(LOG_INFO, "Attempting to register mDNS");
1382                         if ( DNSServiceRegister (&mdns, 0, 0, NULL, "_ntp._udp", NULL, NULL,
1383                             htons(NTP_PORT), 0, NULL, NULL, NULL) != kDNSServiceErr_NoError ) {
1384                                 if (!--mdnstries) {
1385                                         msyslog(LOG_ERR, "Unable to register mDNS, giving up.");
1386                                 } else {
1387                                         msyslog(LOG_INFO, "Unable to register mDNS, will try later.");
1388                                 }
1389                         } else {
1390                                 msyslog(LOG_INFO, "mDNS service registered.");
1391                                 mdnsreg = FALSE;
1392                         }
1393                 }
1394 # endif /* HAVE_DNSREGISTRATION */
1395
1396         }
1397         UNBLOCK_IO_AND_ALARM();
1398         return 1;
1399 }
1400 #endif  /* !SIM */
1401
1402
1403 #if !defined(SIM) && defined(SIGDIE1)
1404 /*
1405  * finish - exit gracefully
1406  */
1407 static void
1408 finish_safe(
1409         int     sig
1410         )
1411 {
1412         const char *sig_desc;
1413
1414         sig_desc = NULL;
1415 #ifdef HAVE_STRSIGNAL
1416         sig_desc = strsignal(sig);
1417 #endif
1418         if (sig_desc == NULL)
1419                 sig_desc = "";
1420         msyslog(LOG_NOTICE, "%s exiting on signal %d (%s)", progname,
1421                 sig, sig_desc);
1422         /* See Bug 2513 and Bug 2522 re the unlink of PIDFILE */
1423 # ifdef HAVE_DNSREGISTRATION
1424         if (mdns != NULL)
1425                 DNSServiceRefDeallocate(mdns);
1426 # endif
1427         peer_cleanup();
1428         exit(0);
1429 }
1430
1431 static RETSIGTYPE
1432 finish(
1433         int     sig
1434         )
1435 {
1436         signalled = 1;
1437         signo = sig;
1438 }
1439
1440 #endif  /* !SIM && SIGDIE1 */
1441
1442
1443 #ifndef SIM
1444 /*
1445  * wait_child_sync_if - implements parent side of -w/--wait-sync
1446  */
1447 # ifdef HAVE_WORKING_FORK
1448 static int
1449 wait_child_sync_if(
1450         int     pipe_read_fd,
1451         long    wait_sync
1452         )
1453 {
1454         int     rc;
1455         int     exit_code;
1456         time_t  wait_end_time;
1457         time_t  cur_time;
1458         time_t  wait_rem;
1459         fd_set  readset;
1460         struct timeval wtimeout;
1461
1462         if (0 == wait_sync)
1463                 return 0;
1464
1465         /* waitsync_fd_to_close used solely by child */
1466         close(waitsync_fd_to_close);
1467         wait_end_time = time(NULL) + wait_sync;
1468         do {
1469                 cur_time = time(NULL);
1470                 wait_rem = (wait_end_time > cur_time)
1471                                 ? (wait_end_time - cur_time)
1472                                 : 0;
1473                 wtimeout.tv_sec = wait_rem;
1474                 wtimeout.tv_usec = 0;
1475                 FD_ZERO(&readset);
1476                 FD_SET(pipe_read_fd, &readset);
1477                 rc = select(pipe_read_fd + 1, &readset, NULL, NULL,
1478                             &wtimeout);
1479                 if (-1 == rc) {
1480                         if (EINTR == errno)
1481                                 continue;
1482                         exit_code = (errno) ? errno : -1;
1483                         msyslog(LOG_ERR,
1484                                 "--wait-sync select failed: %m");
1485                         return exit_code;
1486                 }
1487                 if (0 == rc) {
1488                         /*
1489                          * select() indicated a timeout, but in case
1490                          * its timeouts are affected by a step of the
1491                          * system clock, select() again with a zero
1492                          * timeout to confirm.
1493                          */
1494                         FD_ZERO(&readset);
1495                         FD_SET(pipe_read_fd, &readset);
1496                         wtimeout.tv_sec = 0;
1497                         wtimeout.tv_usec = 0;
1498                         rc = select(pipe_read_fd + 1, &readset, NULL,
1499                                     NULL, &wtimeout);
1500                         if (0 == rc)    /* select() timeout */
1501                                 break;
1502                         else            /* readable */
1503                                 return 0;
1504                 } else                  /* readable */
1505                         return 0;
1506         } while (wait_rem > 0);
1507
1508         fprintf(stderr, "%s: -w/--wait-sync %ld timed out.\n",
1509                 progname, wait_sync);
1510         return ETIMEDOUT;
1511 }
1512 # endif /* HAVE_WORKING_FORK */
1513
1514
1515 /*
1516  * assertion_failed - Redirect assertion failures to msyslog().
1517  */
1518 static void
1519 assertion_failed(
1520         const char *file,
1521         int line,
1522         isc_assertiontype_t type,
1523         const char *cond
1524         )
1525 {
1526         isc_assertion_setcallback(NULL);    /* Avoid recursion */
1527
1528         msyslog(LOG_ERR, "%s:%d: %s(%s) failed",
1529                 file, line, isc_assertion_typetotext(type), cond);
1530         msyslog(LOG_ERR, "exiting (due to assertion failure)");
1531
1532 #if defined(DEBUG) && defined(SYS_WINNT)
1533         if (debug)
1534                 DebugBreak();
1535 #endif
1536
1537         abort();
1538 }
1539
1540
1541 /*
1542  * library_fatal_error - Handle fatal errors from our libraries.
1543  */
1544 static void
1545 library_fatal_error(
1546         const char *file,
1547         int line,
1548         const char *format,
1549         va_list args
1550         )
1551 {
1552         char errbuf[256];
1553
1554         isc_error_setfatal(NULL);  /* Avoid recursion */
1555
1556         msyslog(LOG_ERR, "%s:%d: fatal error:", file, line);
1557         vsnprintf(errbuf, sizeof(errbuf), format, args);
1558         msyslog(LOG_ERR, "%s", errbuf);
1559         msyslog(LOG_ERR, "exiting (due to fatal error in library)");
1560
1561 #if defined(DEBUG) && defined(SYS_WINNT)
1562         if (debug)
1563                 DebugBreak();
1564 #endif
1565
1566         abort();
1567 }
1568
1569
1570 /*
1571  * library_unexpected_error - Handle non fatal errors from our libraries.
1572  */
1573 # define MAX_UNEXPECTED_ERRORS 100
1574 int unexpected_error_cnt = 0;
1575 static void
1576 library_unexpected_error(
1577         const char *file,
1578         int line,
1579         const char *format,
1580         va_list args
1581         )
1582 {
1583         char errbuf[256];
1584
1585         if (unexpected_error_cnt >= MAX_UNEXPECTED_ERRORS)
1586                 return; /* avoid clutter in log */
1587
1588         msyslog(LOG_ERR, "%s:%d: unexpected error:", file, line);
1589         vsnprintf(errbuf, sizeof(errbuf), format, args);
1590         msyslog(LOG_ERR, "%s", errbuf);
1591
1592         if (++unexpected_error_cnt == MAX_UNEXPECTED_ERRORS)
1593                 msyslog(LOG_ERR, "Too many errors.  Shutting up.");
1594
1595 }
1596 #endif  /* !SIM */
1597
1598 #if !defined(SIM) && !defined(SYS_WINNT)
1599 # ifdef DEBUG
1600
1601 /*
1602  * moredebug - increase debugging verbosity
1603  */
1604 static RETSIGTYPE
1605 moredebug(
1606         int sig
1607         )
1608 {
1609         int saved_errno = errno;
1610
1611         if (debug < 255)
1612         {
1613                 debug++;
1614                 msyslog(LOG_DEBUG, "debug raised to %d", debug);
1615         }
1616         errno = saved_errno;
1617 }
1618
1619
1620 /*
1621  * lessdebug - decrease debugging verbosity
1622  */
1623 static RETSIGTYPE
1624 lessdebug(
1625         int sig
1626         )
1627 {
1628         int saved_errno = errno;
1629
1630         if (debug > 0)
1631         {
1632                 debug--;
1633                 msyslog(LOG_DEBUG, "debug lowered to %d", debug);
1634         }
1635         errno = saved_errno;
1636 }
1637
1638 # else  /* !DEBUG follows */
1639
1640
1641 /*
1642  * no_debug - We don't do the debug here.
1643  */
1644 static RETSIGTYPE
1645 no_debug(
1646         int sig
1647         )
1648 {
1649         int saved_errno = errno;
1650
1651         msyslog(LOG_DEBUG, "ntpd not compiled for debugging (signal %d)", sig);
1652         errno = saved_errno;
1653 }
1654 # endif /* !DEBUG */
1655 #endif  /* !SIM && !SYS_WINNT */