/* * ntpdate - set the time of day by polling one or more NTP servers */ #ifdef HAVE_CONFIG_H #include #endif #ifdef HAVE_SYS_TYPES_H #include #endif #ifdef HAVE_UNISTD_H #include #endif #include #include #include #include #ifndef SYS_WINNT #include #include #include #include #include #ifdef __STDC__ #include #else #include #endif #endif /* SYS_WINNT */ #ifdef SYS_VXWORKS #include "ioLib.h" #include "sockLib.h" #include "timers.h" /* select wants a zero structure ... */ struct timeval tv0 = {0,0}; #endif #if defined(SYS_HPUX) #include #endif #include "ntp_fp.h" #include "ntp.h" #include "ntp_io.h" #include "ntp_unixtime.h" #include "ntpdate.h" #include "ntp_string.h" #include "ntp_syslog.h" #include "ntp_select.h" #include "ntp_stdlib.h" #ifdef SYS_WINNT #define TARGET_RESOLUTION 1 /* Try for 1-millisecond accuracy on Windows NT timers. */ #endif /* SYS_WINNT */ /* * Scheduling priority we run at */ #ifndef SYS_VXWORKS #define NTPDATE_PRIO (-12) #else #define NTPDATE_PRIO (100) #endif #if defined(HAVE_TIMER_SETTIME) || defined (HAVE_TIMER_CREATE) /* POSIX TIMERS - vxWorks doesn't have itimer - casey */ static timer_t ntpdate_timerid; #endif /* * Compatibility stuff for Version 2 */ #define NTP_MAXSKW 0x28f /* 0.01 sec in fp format */ #define NTP_MINDIST 0x51f /* 0.02 sec in fp format */ #define PEER_MAXDISP (64*FP_SECOND) /* maximum dispersion (fp 64) */ #define NTP_INFIN 15 /* max stratum, infinity a la Bellman-Ford */ #define NTP_MAXWGT (8*FP_SECOND) /* maximum select weight 8 seconds */ #define NTP_MAXLIST 5 /* maximum select list size */ #define PEER_SHIFT 8 /* 8 suitable for crystal time base */ /* * Debugging flag */ int debug = 0; /* * File descriptor masks etc. for call to select */ int fd; fd_set fdmask; /* * Initializing flag. All async routines watch this and only do their * thing when it is clear. */ int initializing = 1; /* * Alarm flag. Set when an alarm occurs */ volatile int alarm_flag = 0; /* * Simple query flag. */ int simple_query = 0; /* * Unpriviledged port flag. */ int unpriv_port = 0; /* * Time to spend measuring drift rate */ int rate = 0; /* * Program name. */ char *progname; /* * Systemwide parameters and flags */ int sys_samples = DEFSAMPLES; /* number of samples/server */ u_long sys_timeout = DEFTIMEOUT; /* timeout time, in TIMER_HZ units */ struct server **sys_servers; /* the server list */ int sys_numservers = 0; /* number of servers to poll */ int sys_maxservers = 0; /* max number of servers to deal with */ int sys_authenticate = 0; /* true when authenticating */ u_int32 sys_authkey = 0; /* set to authentication key in use */ u_long sys_authdelay = 0; /* authentication delay */ int sys_version = NTP_VERSION; /* version to poll with */ /* * The current internal time */ u_long current_time = 0; /* * Counter for keeping track of completed servers */ int complete_servers = 0; /* * File of encryption keys */ #ifndef KEYFILE # ifndef SYS_WINNT #define KEYFILE "/etc/ntp.keys" # else #define KEYFILE "%windir%\\ntp.keys" # endif /* SYS_WINNT */ #endif /* KEYFILE */ #ifndef SYS_WINNT const char *key_file = KEYFILE; #else char key_file_storage[MAX_PATH+1], *key_file ; #endif /* SYS_WINNT */ /* * Miscellaneous flags */ extern int syslogit; int verbose = 0; int always_step = 0; int never_step = 0; #ifndef SYS_WINNT extern int errno; #endif /* SYS_WINNT */ static void transmit P((struct server *)); static void receive P((struct recvbuf *)); static void server_data P((struct server *, s_fp, l_fp *, u_fp)); static void clock_filter P((struct server *)); static struct server *clock_select P((void)); static int clock_adjust P((void)); static void addserver P((char *)); static struct server *findserver P((struct sockaddr_in *)); static void timer P((void)); static void init_alarm P((void)); #ifndef SYS_WINNT static RETSIGTYPE alarming P((int)); #else void PASCAL alarming P((UINT, UINT,DWORD, DWORD, DWORD)); #endif /* SYS_WINNT */ static void init_io P((void)); static struct recvbuf *getrecvbufs P((void)); static void freerecvbuf P((struct recvbuf *)); static void sendpkt P((struct sockaddr_in *, struct pkt *, int)); static void input_handler P((void)); static int l_adj_systime P((l_fp *)); static int l_step_systime P((l_fp *)); static int getnetnum P((char *, u_int32 *)); static void printserver P((struct server *, FILE *)); #ifdef SYS_WINNT int on = 1; WORD wVersionRequested; WSADATA wsaData; #endif /* SYS_WINNT */ #ifdef NO_MAIN_ALLOWED CALL(ntpdate,"ntpdate",ntpdatemain); void clear_globals() { extern int ntp_optind; /* * Debugging flag */ debug = 0; ntp_optind = 0; /* * Initializing flag. All async routines watch this and only do their * thing when it is clear. */ initializing = 1; /* * Alarm flag. Set when an alarm occurs */ alarm_flag = 0; /* * Simple query flag. */ simple_query = 0; /* * Unpriviledged port flag. */ unpriv_port = 0; /* * Time to spend measuring drift rate */ rate = 0; /* * Systemwide parameters and flags */ sys_numservers = 0; /* number of servers to poll */ sys_maxservers = 0; /* max number of servers to deal with */ sys_authenticate = 0; /* true when authenticating */ sys_authkey = 0; /* set to authentication key in use */ sys_authdelay = 0; /* authentication delay */ sys_version = NTP_VERSION; /* version to poll with */ /* * The current internal time */ current_time = 0; /* * Counter for keeping track of completed servers */ complete_servers = 0; verbose = 0; always_step = 0; never_step = 0; } #endif /* * Main program. Initialize us and loop waiting for I/O and/or * timer expiries. */ void #ifndef NO_MAIN_ALLOWED main #else ntpdatemain #endif /* NO_MAIN_ALLOWED */ (argc, argv) int argc; char *argv[]; { int was_alarmed; struct recvbuf *rbuflist; struct recvbuf *rbuf; l_fp tmp; int errflg; int c; extern char *ntp_optarg; extern int ntp_optind; extern char *Version; #ifdef SYS_WINNT HANDLE process_handle; wVersionRequested = MAKEWORD(1,1); if (WSAStartup(wVersionRequested, &wsaData)) { msyslog(LOG_ERR, "No useable winsock.dll: %m"); exit(1); } key_file = key_file_storage; if (!ExpandEnvironmentStrings(KEYFILE, key_file, MAX_PATH)) { msyslog(LOG_ERR, "ExpandEnvironmentStrings(KEYFILE) failed: %m\n"); } #endif /* SYS_WINNT */ #ifdef NO_MAIN_ALLOWED clear_globals(); #endif errflg = 0; progname = argv[0]; syslogit = 0; /* * Decode argument list */ while ((c = ntp_getopt(argc, argv, "a:bBde:k:o:p:qr:st:uv")) != EOF) switch (c) { case 'a': c = atoi(ntp_optarg); sys_authenticate = 1; sys_authkey = c; break; case 'b': always_step++; never_step = 0; break; case 'B': never_step++; always_step = 0; break; case 'd': ++debug; break; case 'e': if (!atolfp(ntp_optarg, &tmp) || tmp.l_ui != 0) { (void) fprintf(stderr, "%s: encryption delay %s is unlikely\n", progname, ntp_optarg); errflg++; } else { sys_authdelay = tmp.l_uf; } break; case 'k': key_file = ntp_optarg; break; case 'o': sys_version = atoi(ntp_optarg); break; case 'p': c = atoi(ntp_optarg); if (c <= 0 || c > NTP_SHIFT) { (void) fprintf(stderr, "%s: number of samples (%d) is invalid\n", progname, c); errflg++; } else { sys_samples = c; } break; case 'q': simple_query = 1; break; case 'r': c = atoi(ntp_optarg); if (c <= 0 || c > (60 * 60)) { (void) fprintf(stderr, "%s: rate (%d) is invalid: 0 - %d\n", progname, c, (60 * 60)); errflg++; } else { rate = c; } break; case 's': syslogit = 1; break; case 't': if (!atolfp(ntp_optarg, &tmp)) { (void) fprintf(stderr, "%s: timeout %s is undecodeable\n", progname, ntp_optarg); errflg++; } else { sys_timeout = ((LFPTOFP(&tmp) * TIMER_HZ) + 0x8000) >> 16; if (sys_timeout == 0) sys_timeout = 1; } break; case 'v': verbose = 1; break; case 'u': unpriv_port = 1; break; case '?': ++errflg; break; default: break; } sys_maxservers = argc - ntp_optind; if (errflg || sys_maxservers == 0) { (void) fprintf(stderr, "usage: %s [-bBdqsv] [-a key#] [-e delay] [-k file] [-p samples] [-o version#] [-r rate] [-t timeo] server ...\n", progname); exit(2); } sys_servers = (struct server **) emalloc(sys_maxservers * sizeof(struct server *)); if (debug || simple_query) { #ifdef HAVE_SETVBUF static char buf[BUFSIZ]; setvbuf(stdout, buf, _IOLBF, BUFSIZ); #else setlinebuf(stdout); #endif } /* * Logging. Open the syslog if we have to */ if (syslogit) { #if !defined (SYS_WINNT) && !defined (SYS_VXWORKS) #ifndef LOG_DAEMON openlog("ntpdate", LOG_PID); #else #ifndef LOG_NTP #define LOG_NTP LOG_DAEMON #endif openlog("ntpdate", LOG_PID | LOG_NDELAY, LOG_NTP); if (debug) setlogmask(LOG_UPTO(LOG_DEBUG)); else setlogmask(LOG_UPTO(LOG_INFO)); #endif /* LOG_DAEMON */ #endif /* SYS_WINNT */ } if (debug || verbose) msyslog(LOG_NOTICE, "%s", Version); /* * Add servers we are going to be polling */ for ( ; ntp_optind < argc; ntp_optind++) addserver(argv[ntp_optind]); if (sys_numservers == 0) { msyslog(LOG_ERR, "no servers can be used, exiting"); exit(1); } /* * Initialize the time of day routines and the I/O subsystem */ if (sys_authenticate) { init_auth(); if (!authreadkeys(key_file)) { msyslog(LOG_ERR, "no key file, exitting"); exit(1); } if (!authhavekey(sys_authkey)) { char buf[10]; (void) sprintf(buf, "%lu", (unsigned long)sys_authkey); msyslog(LOG_ERR, "authentication key %s unknown", buf); exit(1); } } init_io(); init_alarm(); /* * Set the priority. */ #ifdef SYS_VXWORKS taskPrioritySet( taskIdSelf(), NTPDATE_PRIO); #endif #if defined(HAVE_ATT_NICE) nice (NTPDATE_PRIO); #endif #if defined(HAVE_BSD_NICE) (void) setpriority(PRIO_PROCESS, 0, NTPDATE_PRIO); #endif #ifdef SYS_WINNT process_handle = GetCurrentProcess(); if (!SetPriorityClass(process_handle, (DWORD) REALTIME_PRIORITY_CLASS)) { msyslog(LOG_ERR, "SetPriorityClass failed: %m"); } #endif /* SYS_WINNT */ initializing = 0; was_alarmed = 0; rbuflist = (struct recvbuf *)0; while (complete_servers < sys_numservers) { fd_set rdfdes; int nfound; if (alarm_flag) { /* alarmed? */ was_alarmed = 1; alarm_flag = 0; } rbuflist = getrecvbufs(); /* get received buffers */ if (!was_alarmed && rbuflist == (struct recvbuf *)0) { /* * Nothing to do. Wait for something. */ struct timeval timeout; timeout.tv_sec = 60; /* Give up after 60 seconds */ timeout.tv_usec = 0; rdfdes = fdmask; #ifndef SYS_VXWORKS nfound = select(fd+1, &rdfdes, (fd_set *)0, (fd_set *)0, &timeout); #else nfound = select(fd+1, &rdfdes, (fd_set *)0, (fd_set *)0, &tv0); #endif if (nfound > 0) input_handler(); else if ( #ifndef SYS_WINNT nfound == -1 #else nfound == SOCKET_ERROR #endif /* SYS_WINNT */ ) { #ifndef SYS_WINNT if (errno != EINTR) #endif msyslog(LOG_ERR, "select() error: %m"); } else { #ifndef SYS_VXWORKS msyslog(LOG_DEBUG, "select(): nfound = %d, error: %m", nfound); #endif } if (alarm_flag) { /* alarmed? */ was_alarmed = 1; alarm_flag = 0; } rbuflist = getrecvbufs(); /* get received buffers */ } /* * Out here, signals are unblocked. Call receive * procedure for each incoming packet. */ while (rbuflist != (struct recvbuf *)0) { rbuf = rbuflist; rbuflist = rbuf->next; receive(rbuf); freerecvbuf(rbuf); } /* * Call timer to process any timeouts */ if (was_alarmed) { timer(); was_alarmed = 0; } /* * Go around again */ } /* * When we get here we've completed the polling of all servers. * Adjust the clock, then exit. */ #ifdef SYS_WINNT WSACleanup(); #endif #ifdef SYS_VXWORKS close (fd); timer_delete(ntpdate_timerid); clock_adjust(); #else exit(clock_adjust()); #endif /* SYS_VXWORKS */ } /* * transmit - transmit a packet to the given server, or mark it completed. * This is called by the timeout routine and by the receive * procedure. */ static void transmit(server) register struct server *server; { struct pkt xpkt; if (debug) printf("transmit(%s)\n", ntoa(&server->srcadr)); if (server->filter_nextpt < server->xmtcnt) { l_fp ts; /* * Last message to this server timed out. Shift * zeros into the filter. */ L_CLR(&ts); server_data(server, 0, &ts, 0); } if ((int)server->filter_nextpt >= sys_samples) { /* * Got all the data we need. Mark this guy * completed and return. */ server->event_time = 0; complete_servers++; return; } /* * If we're here, send another message to the server. Fill in * the packet and let 'er rip. */ xpkt.li_vn_mode = PKT_LI_VN_MODE(LEAP_NOTINSYNC, sys_version, MODE_CLIENT); xpkt.stratum = STRATUM_TO_PKT(STRATUM_UNSPEC); xpkt.ppoll = NTP_MINPOLL; xpkt.precision = NTPDATE_PRECISION; xpkt.rootdelay = htonl(NTPDATE_DISTANCE); xpkt.rootdispersion = htonl(NTPDATE_DISP); xpkt.refid = htonl(NTPDATE_REFID); L_CLR(&xpkt.reftime); L_CLR(&xpkt.org); L_CLR(&xpkt.rec); /* * Determine whether to authenticate or not. If so, * fill in the extended part of the packet and do it. * If not, just timestamp it and send it away. */ if (sys_authenticate) { int len; xpkt.keyid = htonl(sys_authkey); auth1crypt(sys_authkey, (u_int32 *)&xpkt, LEN_PKT_NOMAC); get_systime(&server->xmt); L_ADDUF(&server->xmt, sys_authdelay); HTONL_FP(&server->xmt, &xpkt.xmt); len = auth2crypt(sys_authkey, (u_int32 *)&xpkt, LEN_PKT_NOMAC); sendpkt(&(server->srcadr), &xpkt, LEN_PKT_NOMAC + len); if (debug > 1) printf("transmit auth to %s\n", ntoa(&(server->srcadr))); } else { get_systime(&(server->xmt)); HTONL_FP(&server->xmt, &xpkt.xmt); sendpkt(&(server->srcadr), &xpkt, LEN_PKT_NOMAC); if (debug > 1) printf("transmit to %s\n", ntoa(&(server->srcadr))); } /* * Update the server timeout and transmit count */ server->event_time = current_time + sys_timeout; server->xmtcnt++; } /* * receive - receive and process an incoming frame */ static void receive(rbufp) struct recvbuf *rbufp; { register struct pkt *rpkt; register struct server *server; register s_fp di; l_fp t10, t23; l_fp org; l_fp rec; l_fp ci; int has_mac; int is_authentic; if (debug) printf("receive(%s)\n", ntoa(&rbufp->srcadr)); /* * Check to see if the packet basically looks like something * intended for us. */ if (rbufp->recv_length == LEN_PKT_NOMAC) has_mac = 0; else if (rbufp->recv_length >= LEN_PKT_NOMAC) has_mac = 1; else { if (debug) printf("receive: packet length %d\n", rbufp->recv_length); return; /* funny length packet */ } rpkt = &(rbufp->recv_pkt); if (PKT_VERSION(rpkt->li_vn_mode) < NTP_OLDVERSION || PKT_VERSION(rpkt->li_vn_mode) > NTP_VERSION) { return; } if ((PKT_MODE(rpkt->li_vn_mode) != MODE_SERVER && PKT_MODE(rpkt->li_vn_mode) != MODE_PASSIVE) || rpkt->stratum > NTP_MAXSTRATUM) { if (debug) printf("receive: mode %d stratum %d\n", PKT_MODE(rpkt->li_vn_mode), rpkt->stratum); return; } /* * So far, so good. See if this is from a server we know. */ server = findserver(&(rbufp->srcadr)); if (server == NULL) { if (debug) printf("receive: server not found\n"); return; } /* * Decode the org timestamp and make sure we're getting a response * to our last request. */ NTOHL_FP(&rpkt->org, &org); if (!L_ISEQU(&org, &server->xmt)) { if (debug) printf("receive: pkt.org and peer.xmt differ\n"); return; } /* * Check out the authenticity if we're doing that. */ if (!sys_authenticate) is_authentic = 1; else { is_authentic = 0; if (debug > 3) printf("receive: rpkt keyid=%ld sys_authkey=%ld decrypt=%ld\n", (long int)ntohl(rpkt->keyid), (long int)sys_authkey, (long int)authdecrypt(sys_authkey, (u_int32 *)rpkt, LEN_PKT_NOMAC)); if (has_mac && ntohl(rpkt->keyid) == sys_authkey && authdecrypt(sys_authkey, (u_int32 *)rpkt, LEN_PKT_NOMAC)) is_authentic = 1; if (debug) printf("receive: authentication %s\n", is_authentic ? "passed" : "failed"); } server->trust <<= 1; if (!is_authentic) server->trust |= 1; /* * Looks good. Record info from the packet. */ server->leap = PKT_LEAP(rpkt->li_vn_mode); server->stratum = PKT_TO_STRATUM(rpkt->stratum); server->precision = rpkt->precision; server->rootdelay = ntohl(rpkt->rootdelay); server->rootdispersion = ntohl(rpkt->rootdispersion); server->refid = rpkt->refid; NTOHL_FP(&rpkt->reftime, &server->reftime); NTOHL_FP(&rpkt->rec, &rec); NTOHL_FP(&rpkt->xmt, &server->org); /* * Make sure the server is at least somewhat sane. If not, try * again. */ if (L_ISZERO(&rec) || !L_ISHIS(&server->org, &rec)) { transmit(server); return; } /* * Calculate the round trip delay (di) and the clock offset (ci). * We use the equations (reordered from those in the spec): * * d = (t2 - t3) - (t1 - t0) * c = ((t2 - t3) + (t1 - t0)) / 2 */ t10 = server->org; /* pkt.xmt == t1 */ L_SUB(&t10, &rbufp->recv_time); /* recv_time == t0*/ t23 = rec; /* pkt.rec == t2 */ L_SUB(&t23, &org); /* pkt->org == t3 */ /* now have (t2 - t3) and (t0 - t1). Calculate (ci) and (di) */ ci = t10; L_ADD(&ci, &t23); L_RSHIFT(&ci); /* * Calculate di in t23 in full precision, then truncate * to an s_fp. */ L_SUB(&t23, &t10); di = LFPTOFP(&t23); if (debug > 3) printf("offset: %s, delay %s\n", lfptoa(&ci, 6), fptoa(di, 5)); di += (FP_SECOND >> (-(int)NTPDATE_PRECISION)) + (FP_SECOND >> (-(int)server->precision)) + NTP_MAXSKW; if (di <= 0) { /* value still too raunchy to use? */ L_CLR(&ci); di = 0; } else { di = max(di, NTP_MINDIST); } /* * Shift this data in, then transmit again. */ server_data(server, (u_fp) di, &ci, 0); transmit(server); } /* * server_data - add a sample to the server's filter registers */ static void server_data(server, d, c, e) register struct server *server; s_fp d; l_fp *c; u_fp e; { register int i; i = server->filter_nextpt; if (i < NTP_SHIFT) { server->filter_delay[i] = d; server->filter_offset[i] = *c; server->filter_soffset[i] = LFPTOFP(c); server->filter_error[i] = e; server->filter_nextpt = i + 1; } } /* * clock_filter - determine a server's delay, dispersion and offset */ static void clock_filter(server) register struct server *server; { register int i, j; int ord[NTP_SHIFT]; /* * Sort indices into increasing delay order */ for (i = 0; i < sys_samples; i++) ord[i] = i; for (i = 0; i < (sys_samples-1); i++) { for (j = i+1; j < sys_samples; j++) { if (server->filter_delay[ord[j]] == 0) continue; if (server->filter_delay[ord[i]] == 0 || (server->filter_delay[ord[i]] > server->filter_delay[ord[j]])) { register int tmp; tmp = ord[i]; ord[i] = ord[j]; ord[j] = tmp; } } } /* * Now compute the dispersion, and assign values to delay and * offset. If there are no samples in the register, delay and * offset go to zero and dispersion is set to the maximum. */ if (server->filter_delay[ord[0]] == 0) { server->delay = 0; L_CLR(&server->offset); server->soffset = 0; server->dispersion = PEER_MAXDISP; } else { register s_fp d; server->delay = server->filter_delay[ord[0]]; server->offset = server->filter_offset[ord[0]]; server->soffset = LFPTOFP(&server->offset); server->dispersion = 0; for (i = 1; i < sys_samples; i++) { if (server->filter_delay[ord[i]] == 0) d = PEER_MAXDISP; else { d = server->filter_soffset[ord[i]] - server->filter_soffset[ord[0]]; if (d < 0) d = -d; if (d > PEER_MAXDISP) d = PEER_MAXDISP; } /* * XXX This *knows* PEER_FILTER is 1/2 */ server->dispersion += (u_fp)(d) >> i; } } /* * We're done */ } /* * clock_select - select the pick-of-the-litter clock from the samples * we've got. */ static struct server * clock_select() { register struct server *server; register int i; register int nlist; register s_fp d; register int j; register int n; s_fp local_threshold; struct server *server_list[NTP_MAXCLOCK]; u_fp server_badness[NTP_MAXCLOCK]; struct server *sys_server; /* * This first chunk of code is supposed to go through all * servers we know about to find the NTP_MAXLIST servers which * are most likely to succeed. We run through the list * doing the sanity checks and trying to insert anyone who * looks okay. We are at all times aware that we should * only keep samples from the top two strata and we only need * NTP_MAXLIST of them. */ nlist = 0; /* none yet */ for (n = 0; n < sys_numservers; n++) { server = sys_servers[n]; if (server->delay == 0) continue; /* no data */ if (server->stratum > NTP_INFIN) continue; /* stratum no good */ if (server->delay > NTP_MAXWGT) { continue; /* too far away */ } if (server->leap == LEAP_NOTINSYNC) continue; /* he's in trouble */ if (!L_ISHIS(&server->org, &server->reftime)) { continue; /* very broken host */ } if ((server->org.l_ui - server->reftime.l_ui) >= NTP_MAXAGE) { continue; /* too long without sync */ } if (server->trust != 0) { continue; } /* * This one seems sane. Find where he belongs * on the list. */ d = server->dispersion + server->dispersion; for (i = 0; i < nlist; i++) if (server->stratum <= server_list[i]->stratum) break; for ( ; i < nlist; i++) { if (server->stratum < server_list[i]->stratum) break; if (d < (s_fp) server_badness[i]) break; } /* * If i points past the end of the list, this * guy is a loser, else stick him in. */ if (i >= NTP_MAXLIST) continue; for (j = nlist; j > i; j--) if (j < NTP_MAXLIST) { server_list[j] = server_list[j-1]; server_badness[j] = server_badness[j-1]; } server_list[i] = server; server_badness[i] = d; if (nlist < NTP_MAXLIST) nlist++; } /* * Got the five-or-less best. Cut the list where the number of * strata exceeds two. */ j = 0; for (i = 1; i < nlist; i++) if (server_list[i]->stratum > server_list[i-1]->stratum) if (++j == 2) { nlist = i; break; } /* * Whew! What we should have by now is 0 to 5 candidates for * the job of syncing us. If we have none, we're out of luck. * If we have one, he's a winner. If we have more, do falseticker * detection. */ if (nlist == 0) sys_server = 0; else if (nlist == 1) { sys_server = server_list[0]; } else { /* * Re-sort by stratum, bdelay estimate quality and * server.delay. */ for (i = 0; i < nlist-1; i++) for (j = i+1; j < nlist; j++) { if (server_list[i]->stratum < server_list[j]->stratum) break; /* already sorted by stratum */ if (server_list[i]->delay < server_list[j]->delay) continue; server = server_list[i]; server_list[i] = server_list[j]; server_list[j] = server; } /* * Calculate the fixed part of the dispersion limit */ local_threshold = (FP_SECOND >> (-(int)NTPDATE_PRECISION)) + NTP_MAXSKW; /* * Now drop samples until we're down to one. */ while (nlist > 1) { for (n = 0; n < nlist; n++) { server_badness[n] = 0; for (j = 0; j < nlist; j++) { if (j == n) /* with self? */ continue; d = server_list[j]->soffset - server_list[n]->soffset; if (d < 0) /* absolute value */ d = -d; /* * XXX This code *knows* that * NTP_SELECT is 3/4 */ for (i = 0; i < j; i++) d = (d>>1) + (d>>2); server_badness[n] += d; } } /* * We now have an array of nlist badness * coefficients. Find the badest. Find * the minimum precision while we're at * it. */ i = 0; n = server_list[0]->precision;; for (j = 1; j < nlist; j++) { if (server_badness[j] >= server_badness[i]) i = j; if (n > server_list[j]->precision) n = server_list[j]->precision; } /* * i is the index of the server with the worst * dispersion. If his dispersion is less than * the threshold, stop now, else delete him and * continue around again. */ if ( (s_fp) server_badness[i] < (local_threshold + (FP_SECOND >> (-n)))) break; for (j = i + 1; j < nlist; j++) server_list[j-1] = server_list[j]; nlist--; } /* * What remains is a list of less than 5 servers. Take * the best. */ sys_server = server_list[0]; } /* * That's it. Return our server. */ return sys_server; } /* * clock_adjust - process what we've received, and adjust the time * if we got anything decent. */ static int clock_adjust() { register int i; register struct server *server; s_fp absoffset; int dostep; for (i = 0; i < sys_numservers; i++) clock_filter(sys_servers[i]); server = clock_select(); if (debug || simple_query) { for (i = 0; i < sys_numservers; i++) printserver(sys_servers[i], stdout); } if (server == 0) { msyslog(LOG_ERR, "no server suitable for synchronization found"); return(1); } if (always_step) { dostep = 1; } else if (never_step) { dostep = 0; } else { absoffset = server->soffset; if (absoffset < 0) absoffset = -absoffset; dostep = (absoffset >= NTPDATE_THRESHOLD); } if (dostep) { if (simple_query || l_step_systime(&server->offset)) { msyslog(LOG_NOTICE, "step time server %s offset %s sec", ntoa(&server->srcadr), lfptoa(&server->offset, 6)); } } else { #ifndef SYS_WINNT if (simple_query || l_adj_systime(&server->offset)) { msyslog(LOG_NOTICE, "adjust time server %s offset %s sec", ntoa(&server->srcadr), lfptoa(&server->offset, 6)); } #else /* The NT SetSystemTimeAdjustment() call achieves slewing by * changing the clock frequency. This means that we cannot specify * it to slew the clock by a definite amount and then stop like * the Unix adjtime() routine. We can technically adjust the clock * frequency, have ntpdate sleep for a while, and then wake * up and reset the clock frequency, but this might cause some * grief if the user attempts to run xntpd immediately after * ntpdate and the socket is in use. */ printf("\nThe -b option is required by ntpdate on Windows NT platforms\n"); exit(1); #endif /* SYS_WINNT */ } return(0); } /* XXX ELIMINATE: merge BIG slew into adj_systime in lib/systime.c */ /* * addserver - determine a server's address and allocate a new structure * for it. */ static void addserver(serv) char *serv; { register struct server *server; u_int32 netnum; static int toomany = 0; if (sys_numservers >= sys_maxservers) { if (!toomany) { /* * This is actually a `can't happen' now. Leave * the error message in anyway, though */ toomany = 1; msyslog(LOG_ERR, "too many servers (> %d) specified, remainder not used", sys_maxservers); } return; } if (!getnetnum(serv, &netnum)) { msyslog(LOG_ERR, "can't find host %s\n", serv); return; } server = (struct server *)emalloc(sizeof(struct server)); memset((char *)server, 0, sizeof(struct server)); server->srcadr.sin_family = AF_INET; server->srcadr.sin_addr.s_addr = netnum; server->srcadr.sin_port = htons(NTP_PORT); sys_servers[sys_numservers++] = server; server->event_time = sys_numservers; } /* * findserver - find a server in the list given its address */ static struct server * findserver(addr) struct sockaddr_in *addr; { register int i; register u_int32 netnum; if (htons(addr->sin_port) != NTP_PORT) return 0; netnum = addr->sin_addr.s_addr; for (i = 0; i < sys_numservers; i++) { if (netnum == sys_servers[i]->srcadr.sin_addr.s_addr) return sys_servers[i]; } return 0; } /* * timer - process a timer interrupt */ static void timer() { register int i; /* * Bump the current idea of the time */ current_time++; /* * Search through the server list looking for guys * who's event timers have expired. Give these to * the transmit routine. */ for (i = 0; i < sys_numservers; i++) { if (sys_servers[i]->event_time != 0 && sys_servers[i]->event_time <= current_time) transmit(sys_servers[i]); } } /* * init_alarm - set up the timer interrupt */ static void init_alarm() { #ifndef SYS_WINNT #ifndef HAVE_TIMER_SETTIME struct itimerval itimer; #else struct itimerspec ntpdate_itimer; #endif #else TIMECAPS tc; HANDLE hToken; TOKEN_PRIVILEGES tkp; UINT wTimerRes, wTimerID; DWORD dwUser = 0; #endif /* SYS_WINNT */ alarm_flag = 0; #ifndef SYS_WINNT #if defined(HAVE_TIMER_CREATE) && defined(HAVE_TIMER_SETTIME) alarm_flag = 0; /* this code was put in as setitimer() is non existant this us the * POSIX "equivalents" setup - casey */ /* ntpdate_timerid is global - so we can kill timer later */ if (timer_create (CLOCK_REALTIME, NULL, &ntpdate_timerid) == #ifdef SYS_VXWORKS ERROR #else -1 #endif ) { fprintf (stderr, "init_alarm(): timer_create (...) FAILED\n"); return; } /* TIMER_HZ = (5) * Set up the alarm interrupt. The first comes 1/(2*TIMER_HZ) * seconds from now and they continue on every 1/TIMER_HZ seconds. */ (void) signal_no_reset(SIGALRM, alarming); ntpdate_itimer.it_interval.tv_sec = ntpdate_itimer.it_value.tv_sec = 0; ntpdate_itimer.it_interval.tv_nsec = 1000000000/TIMER_HZ; ntpdate_itimer.it_value.tv_nsec = 1000000000/(TIMER_HZ<<1); timer_settime(ntpdate_timerid, 0 /* !TIMER_ABSTIME */, &ntpdate_itimer, NULL); #else /* * Set up the alarm interrupt. The first comes 1/(2*TIMER_HZ) * seconds from now and they continue on every 1/TIMER_HZ seconds. */ (void) signal_no_reset(SIGALRM, alarming); itimer.it_interval.tv_sec = itimer.it_value.tv_sec = 0; itimer.it_interval.tv_usec = 1000000/TIMER_HZ; itimer.it_value.tv_usec = 1000000/(TIMER_HZ<<1); setitimer(ITIMER_REAL, &itimer, (struct itimerval *)0); #endif #else /* SYS_WINNT */ _tzset(); /* * Get previleges needed for fiddling with the clock */ /* get the current process token handle */ if (!OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken)) { msyslog(LOG_ERR, "OpenProcessToken failed: %m"); exit(1); } /* get the LUID for system-time privilege. */ LookupPrivilegeValue(NULL, SE_SYSTEMTIME_NAME, &tkp.Privileges[0].Luid); tkp.PrivilegeCount = 1; /* one privilege to set */ tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED; /* get set-time privilege for this process. */ AdjustTokenPrivileges(hToken, FALSE, &tkp, 0,(PTOKEN_PRIVILEGES) NULL, 0); /* cannot test return value of AdjustTokenPrivileges. */ if (GetLastError() != ERROR_SUCCESS) msyslog(LOG_ERR, "AdjustTokenPrivileges failed: %m"); /* * Set up timer interrupts for every 2**EVENT_TIMEOUT seconds * Under Win/NT, expiry of timer interval leads to invocation * of a callback function (on a different thread) rather than * generating an alarm signal */ /* determine max and min resolution supported */ if(timeGetDevCaps(&tc, sizeof(TIMECAPS)) != TIMERR_NOERROR) { msyslog(LOG_ERR, "timeGetDevCaps failed: %m"); exit(1); } wTimerRes = min(max(tc.wPeriodMin, TARGET_RESOLUTION), tc.wPeriodMax); /* establish the minimum timer resolution that we'll use */ timeBeginPeriod(wTimerRes); /* start the timer event */ wTimerID = timeSetEvent( (UINT) (1000/TIMER_HZ), /* Delay */ wTimerRes, /* Resolution */ (LPTIMECALLBACK) alarming, /* Callback function */ (DWORD) dwUser, /* User data */ TIME_PERIODIC); /* Event type (periodic) */ if (wTimerID == 0) { msyslog(LOG_ERR, "timeSetEvent failed: %m"); exit(1); } #endif /* SYS_WINNT */ } #ifndef SYS_WINNT /* * alarming - record the occurance of an alarm interrupt */ static RETSIGTYPE alarming(sig) int sig; { alarm_flag++; } #else /* SYS_WINNT */ /* * alarming for WinNT - invoke the timer() routine */ void PASCAL alarming (UINT wTimerID, UINT msg, DWORD dwUser, DWORD dw1, DWORD dw2) { extern int debug; static int initializing2 = 1; extern int fd; HANDLE TimerThreadHandle; static DWORD threadID; #ifdef DEBUG SYSTEMTIME st; #endif if (initializing2) { TimerThreadHandle = GetCurrentThread(); if (!SetThreadPriority(TimerThreadHandle, (DWORD) THREAD_PRIORITY_HIGHEST)) msyslog(LOG_ERR, "SetThreadPriority: %m"); threadID = GetCurrentThreadId(); initializing2 = 0; } #ifdef DEBUG if (debug > 3) { GetSystemTime(&st); printf("thread %u (timer callback): time %02u:%02u:%02u:%03u\n", threadID, st.wHour, st.wMinute, st.wSecond, st.wMilliseconds); fflush(stdout); } #endif timer(); UNREFERENCED_PARAMETER(dw1); UNREFERENCED_PARAMETER(dw2); UNREFERENCED_PARAMETER(dwUser); UNREFERENCED_PARAMETER(msg); UNREFERENCED_PARAMETER(wTimerID); } #endif /* SYS_WINNT */ /* * We do asynchronous input using the SIGIO facility. A number of * recvbuf buffers are preallocated for input. In the signal * handler we poll to see if the socket is ready and read the * packets from it into the recvbuf's along with a time stamp and * an indication of the source host and the interface it was received * through. This allows us to get as accurate receive time stamps * as possible independent of other processing going on. * * We allocate a number of recvbufs equal to the number of servers * plus 2. This should be plenty. */ /* * recvbuf lists */ struct recvbuf *freelist; /* free buffers */ struct recvbuf *fulllist; /* buffers with data */ int full_recvbufs; /* number of full ones */ int free_recvbufs; /* * init_io - initialize I/O data and open socket */ static void init_io() { register int i; register struct recvbuf *rb; /* * Init buffer free list and stat counters */ rb = (struct recvbuf *) emalloc((sys_numservers + 2) * sizeof(struct recvbuf)); freelist = 0; for (i = sys_numservers + 2; i > 0; i--) { rb->next = freelist; freelist = rb; rb++; } fulllist = 0; full_recvbufs = 0; free_recvbufs = sys_numservers + 2; /* * Open the socket */ /* create a datagram (UDP) socket */ if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { msyslog(LOG_ERR, "socket() failed: %m"); exit(1); /*NOTREACHED*/ } /* * bind the socket to the NTP port */ if (!debug && !simple_query && !unpriv_port) { struct sockaddr_in addr; memset((char *)&addr, 0, sizeof addr); addr.sin_family = AF_INET; addr.sin_port = htons(NTP_PORT); addr.sin_addr.s_addr = htonl(INADDR_ANY); if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) { #ifndef SYS_WINNT if (errno == EADDRINUSE) #else if (WSAGetLastError() == WSAEADDRINUSE) #endif /* SYS_WINNT */ msyslog(LOG_ERR, "the NTP socket is in use, exiting"); else msyslog(LOG_ERR, "bind() fails: %m"); exit(1); } } FD_ZERO(&fdmask); FD_SET(fd, &fdmask); /* * set non-blocking, */ #ifndef SYS_WINNT #ifdef SYS_VXWORKS { int on = TRUE; if (ioctl(fd,FIONBIO, &on) == ERROR) { msyslog(LOG_ERR, "ioctl(FIONBIO) fails: %m"); exit(1); } } #else #if defined(O_NONBLOCK) if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) { msyslog(LOG_ERR, "fcntl(FNDELAY|FASYNC) fails: %m"); exit(1); /*NOTREACHED*/ } #else /* O_NONBLOCK */ #if defined(FNDELAY) if (fcntl(fd, F_SETFL, FNDELAY) < 0) { msyslog(LOG_ERR, "fcntl(FNDELAY|FASYNC) fails: %m"); exit(1); /*NOTREACHED*/ } #else /* FNDELAY */ # include "Bletch: Need non blocking I/O" #endif /* FNDELAY */ #endif /* SYS_VXWORKS */ #endif /* O_NONBLOCK */ #else /* SYS_WINNT */ if (ioctlsocket(fd, FIONBIO, (u_long *) &on) == SOCKET_ERROR) { msyslog(LOG_ERR, "ioctlsocket(FIONBIO) fails: %m"); exit(1); } #endif /* SYS_WINNT */ } /* XXX ELIMINATE getrecvbufs (almost) identical to ntpdate.c, ntptrace.c, ntp_io.c */ /* * getrecvbufs - get receive buffers which have data in them * * ***N.B. must be called with SIGIO blocked*** */ static struct recvbuf * getrecvbufs() { struct recvbuf *rb; if (full_recvbufs == 0) { return (struct recvbuf *)0; /* nothing has arrived */ } /* * Get the fulllist chain and mark it empty */ rb = fulllist; fulllist = 0; full_recvbufs = 0; /* * Return the chain */ return rb; } /* XXX ELIMINATE freerecvbuf (almost) identical to ntpdate.c, ntptrace.c, ntp_io.c */ /* * freerecvbuf - make a single recvbuf available for reuse */ static void freerecvbuf(rb) struct recvbuf *rb; { rb->next = freelist; freelist = rb; free_recvbufs++; } /* * sendpkt - send a packet to the specified destination */ static void sendpkt(dest, pkt, len) struct sockaddr_in *dest; struct pkt *pkt; int len; { int cc; #ifdef SYS_WINNT DWORD err; #endif /* SYS_WINNT */ cc = sendto(fd, (char *)pkt, len, 0, (struct sockaddr *)dest, sizeof(struct sockaddr_in)); #ifndef SYS_WINNT if (cc == -1) { if (errno != EWOULDBLOCK && errno != ENOBUFS) msyslog(LOG_ERR, "sendto(%s): %m", ntoa(dest)); } #else if (cc == SOCKET_ERROR) { err = WSAGetLastError(); if (err != WSAEWOULDBLOCK && err != WSAENOBUFS) msyslog(LOG_ERR, "sendto(%s): %m", ntoa(dest)); } #endif /* SYS_WINNT */ } /* * input_handler - receive packets asynchronously */ static void input_handler() { register int n; register struct recvbuf *rb; struct timeval tvzero; int fromlen; l_fp ts; fd_set fds; /* * Do a poll to see if we have data */ for (;;) { fds = fdmask; tvzero.tv_sec = tvzero.tv_usec = 0; n = select(fd+1, &fds, (fd_set *)0, (fd_set *)0, &tvzero); /* * If nothing to do, just return. If an error occurred, * complain and return. If we've got some, freeze a * timestamp. */ if (n == 0) return; else if (n == -1) { if (errno != EINTR) msyslog(LOG_ERR, "select() error: %m"); return; } get_systime(&ts); /* * Get a buffer and read the frame. If we * haven't got a buffer, or this is received * on the wild card socket, just dump the packet. */ if (initializing || free_recvbufs == 0) { char buf[100]; #ifndef SYS_WINNT (void) read(fd, buf, sizeof buf); #else /* NT's _read does not operate on nonblocking sockets * either recvfrom or ReadFile() has to be used here. * ReadFile is used in [xntpd]ntp_intres() and xntpdc, * just to be different use recvfrom() here */ recvfrom(fd, buf, sizeof(buf), 0, (struct sockaddr *)0, NULL); #endif /* SYS_WINNT */ continue; } rb = freelist; freelist = rb->next; free_recvbufs--; fromlen = sizeof(struct sockaddr_in); rb->recv_length = recvfrom(fd, (char *)&rb->recv_pkt, sizeof(rb->recv_pkt), 0, (struct sockaddr *)&rb->srcadr, &fromlen); if (rb->recv_length == -1) { rb->next = freelist; freelist = rb; free_recvbufs++; continue; } /* * Got one. Mark how and when it got here, * put it on the full list. */ rb->recv_time = ts; rb->next = fulllist; fulllist = rb; full_recvbufs++; } } #ifndef SYS_WINNT /* * adj_systime - do a big long slew of the system time */ static int l_adj_systime(ts) l_fp *ts; { struct timeval adjtv, oadjtv; int isneg = 0; l_fp offset; #ifndef STEP_SLEW l_fp overshoot; #endif /* * Take the absolute value of the offset */ offset = *ts; if (L_ISNEG(&offset)) { isneg = 1; L_NEG(&offset); } #ifndef STEP_SLEW /* * Calculate the overshoot. XXX N.B. This code *knows* * ADJ_OVERSHOOT is 1/2. */ overshoot = offset; L_RSHIFTU(&overshoot); if (overshoot.l_ui != 0 || (overshoot.l_uf > ADJ_MAXOVERSHOOT)) { overshoot.l_ui = 0; overshoot.l_uf = ADJ_MAXOVERSHOOT; } L_ADD(&offset, &overshoot); #endif TSTOTV(&offset, &adjtv); if (isneg) { adjtv.tv_sec = -adjtv.tv_sec; adjtv.tv_usec = -adjtv.tv_usec; } if (adjtv.tv_usec != 0 && !debug) { if (adjtime(&adjtv, &oadjtv) < 0) { msyslog(LOG_ERR, "Can't adjust the time of day: %m"); return 0; } } return 1; } #endif /* SYS_WINNT */ /* * This fuction is not the same as lib/systime step_systime!!! */ static int l_step_systime(ts) l_fp *ts; { #ifdef SLEWALWAYS #ifdef STEP_SLEW l_fp ftmp; int isneg; int n; if (debug) return 1; /* * Take the absolute value of the offset */ ftmp = *ts; if (L_ISNEG(&ftmp)) { L_NEG(&ftmp); isneg = 1; } else isneg = 0; if (ftmp.l_ui >= 3) { /* Step it and slew - we might win */ n = step_systime_real(ts); if (!n) return n; if (isneg) ts->l_ui = ~0; else ts->l_ui = ~0; } /* * Just add adjustment into the current offset. The update * routine will take care of bringing the system clock into * line. */ #endif if (debug) return 1; #ifdef FORCE_NTPDATE_STEP return step_systime_real(ts); #else l_adj_systime(ts); return 1; #endif #else /* SLEWALWAYS */ if (debug) return 1; return step_systime_real(ts); #endif /* SLEWALWAYS */ } /* * getnetnum - given a host name, return its net number */ static int getnetnum(host, num) char *host; u_int32 *num; { struct hostent *hp; if (decodenetnum(host, num)) { return 1; } else if ((hp = gethostbyname(host)) != 0) { memmove((char *)num, hp->h_addr, sizeof(u_int32)); return (1); } return (0); } /* XXX ELIMINATE printserver similar in ntptrace.c, ntpdate.c */ /* * printserver - print detail information for a server */ static void printserver(pp, fp) register struct server *pp; FILE *fp; { register int i; char junk[5]; char *str; if (!debug) { (void) fprintf(fp, "server %s, stratum %d, offset %s, delay %s\n", ntoa(&pp->srcadr), pp->stratum, lfptoa(&pp->offset, 6), fptoa(pp->delay, 5)); return; } (void) fprintf(fp, "server %s, port %d\n", ntoa(&pp->srcadr), ntohs(pp->srcadr.sin_port)); (void) fprintf(fp, "stratum %d, precision %d, leap %c%c, trust %03o\n", pp->stratum, pp->precision, pp->leap & 0x2 ? '1' : '0', pp->leap & 0x1 ? '1' : '0', pp->trust); if (pp->stratum == 1) { junk[4] = 0; memmove(junk, (char *)&pp->refid, 4); str = junk; } else { str = numtoa(pp->refid); } (void) fprintf(fp, "refid [%s], delay %s, dispersion %s\n", str, fptoa(pp->delay, 5), ufptoa(pp->dispersion, 5)); (void) fprintf(fp, "transmitted %d, in filter %d\n", pp->xmtcnt, pp->filter_nextpt); (void) fprintf(fp, "reference time: %s\n", prettydate(&pp->reftime)); (void) fprintf(fp, "originate timestamp: %s\n", prettydate(&pp->org)); (void) fprintf(fp, "transmit timestamp: %s\n", prettydate(&pp->xmt)); (void) fprintf(fp, "filter delay: "); for (i = 0; i < NTP_SHIFT; i++) { (void) fprintf(fp, " %-8.8s", fptoa(pp->filter_delay[i], 5)); if (i == (NTP_SHIFT>>1)-1) (void) fprintf(fp, "\n "); } (void) fprintf(fp, "\n"); (void) fprintf(fp, "filter offset:"); for (i = 0; i < PEER_SHIFT; i++) { (void) fprintf(fp, " %-8.8s", lfptoa(&pp->filter_offset[i], 6)); if (i == (PEER_SHIFT>>1)-1) (void) fprintf(fp, "\n "); } (void) fprintf(fp, "\n"); (void) fprintf(fp, "delay %s, dispersion %s\n", fptoa(pp->delay, 5), ufptoa(pp->dispersion, 5)); (void) fprintf(fp, "offset %s\n\n", lfptoa(&pp->offset, 6)); } #if !defined(HAVE_VSPRINTF) /* * This nugget for pre-tahoe 4.3bsd systems */ #if !defined(__STDC__) || !__STDC__ #define const #endif int vsprintf(str, fmt, ap) char *str; const char *fmt; va_list ap; { FILE f; int len; f._flag = _IOWRT+_IOSTRG; f._ptr = str; f._cnt = 32767; len = _doprnt(fmt, ap, &f); *f._ptr = 0; return (len); } #endif #if 0 /* override function in library since SA_RESTART makes ALL syscalls restart */ #ifdef SA_RESTART void signal_no_reset(sig, func) int sig; void (*func)(); { int n; struct sigaction vec; vec.sa_handler = func; sigemptyset(&vec.sa_mask); vec.sa_flags = 0; while (1) { n = sigaction(sig, &vec, NULL); if (n == -1 && errno == EINTR) continue; break; } if (n == -1) { perror("sigaction"); exit(1); } } #endif #endif