ntpd.c

ftam等标准协议服务器和客户端的源代码。

#ifndef	lint
static char *rcsid = "$Header: /xtel/isode/isode/others/ntp/RCS/ntpd.c,v 9.0 1992/06/16 14:45:01 isode Rel $";
#endif	lint

/*
 * ntp daemon - based on the 3.4 version but heavily modified for OSI
 * interworking.
 *
 * $Log: ntpd.c,v $
 * Revision 9.0  1992/06/16  14:45:01  isode
 * Release 8.0
 *
 * 
 */


#include "ntp.h"
#include "patchlevel.h"

#ifndef L_SET
#define L_SET SEEK_SET
#endif

char	*conf = NTPINITFILE;
char 	*driftcomp_file = NTPDRIFTCOMP;
char	*osiaddress = "Internet=localhost+10123";
char	*myname = "ntpd";

int	doset = 1;
int	selfds = 0;
int	trusting = 1;
int	keepallpeers = 1;
int	logstats;
#ifdef	DEBUG
int	debug = 0;
#endif
#ifdef	SETTICKADJ
int	tickadj = 0;
int	dotickadj = 0;
#endif
#ifdef	NOSWAP
int	noswap = 0;
#endif

unsigned int	servport;
unsigned long clock_watchdog;

double WayTooBig = WAYTOOBIG;


struct list	peer_list;
struct timeval 	tv;
struct ntpdata	ntpframe;
struct sysdata	sys;

fd_set globmask, globwmask;

/* STATIC data */
static int drift_fd = -1;

static LLog _pgm_log = {
	"ntp.log", NULLCP, NULLCP,
	LLOG_FATAL | LLOG_EXCEPTIONS | LLOG_NOTICE, LLOG_FATAL, -1,
	LLOGCLS | LLOGCRT, NOTOK
};
LLog *pgm_log = &_pgm_log;

static int priority = -10;
static int ticked;


static void timeout();
static void init_ntp();
void initialize();
static void init_kern_vars();
static void hourly();
static void do_peer ();
static SFD finish ();

extern void make_new_peer();
extern void transmit();
extern void process_packet();
extern void clock_update();
extern void clear();
extern void clock_filter();
extern void select_clock();
extern void advise ();
extern void adios ();
extern void init_logical_clock();
extern void create_osilisten ();
extern void iso_init ();
extern void poll_update();

#if	defined(DEBUG) && defined(SIGUSR1) && defined(SIGUSR2)
static	SFD incdebug(), decdebug();
#endif

struct ntp_peer *find_peer ();

main(argc, argv)
int argc;
char *argv[];
{
	int	cc;
	extern char *optarg;
	register int i;

	if (myname = rindex (argv[0], '/'))
		myname++;
	if (myname == NULL || *myname == NULL)
		myname = argv[0];

	isodetailor (myname, 0);
	initialize();		/* call NTP protocol initialization first,
				   then allow others to override default
				   values */

	while ((cc = getopt(argc, argv, "a:c:dD:lstnp:")) != EOF) {
		switch (cc) {
		    case 'a':
			if (strcmp(optarg, "any") == 0)
				WayTooBig = 10e15;
			else
				WayTooBig = atof(optarg);
			break;

		    case 'd':
#ifdef	DEBUG
			debug++;
#else
			adios (NULLCP, "%s: not compiled with DEBUG", myname);
#endif
			break;

		    case 'D':
#ifdef	DEBUG
			debug = atoi(optarg);
#else
			adios (NULLCP, "%s: not compiled with DEBUG", myname);
#endif
			break;

		    case 's':
			doset = 0;
			break;

		    case 't':
#ifdef	SETTICKADJ
			dotickadj++;
#else
			adios (NULLCP, "%s: not compiled to set tickadj",
			       myname);
#endif
			break;

		    case 'n':
#ifdef	NOSWAP
			noswap = 1;
#else
			adios (NULLCP, "%s: not compiled for noswap",
			       myname);
#endif
			break;

		    case 'l':
			logstats = 1;
			break;

		    case 'c':
			conf = optarg;
			break;

		    case 'p':
			servport = htons (atoi(optarg));
			break;
		    default:
			adios (NULLCP, "ntpd: -%c: unknown option", cc);
			break;
		}
	}

	if (servport == 0) {
		struct servent *sp;

		if ((sp = getservbyname ("ntp", "udp")) == NULL)
			servport = htons (NTP_PORT);
		else	servport = sp -> s_port;
	}
		


	peer_list.head = peer_list.tail = NULL;
	peer_list.members = 0;
	srandom(getpid ());

	init_ntp(conf);
	init_kern_vars();
	init_logical_clock();

	envinit ();
	create_listeners ();
	/*
	 * Attempt to open for writing the file for storing the drift comp
	 * register.  File must already exist for snapshots to be taken.
	 */
	if ((i = open(driftcomp_file, O_WRONLY|O_CREAT, 0644)) >= 0) {
		drift_fd = i;
	}
	doit ();

	return 0;
}

doit ()
{
	struct timeval tvt;
	fd_set readfds, writefds;
	int	vecp;
	char *vec[4];
	struct TSAPdisconnect tds;
	struct TSAPdisconnect *td = &tds;
	register int i;
	int	newfd;

	(void) gettimeofday(&tv, (struct timezone *) 0);

	FD_ZERO(&globmask);
	FD_ZERO(&globwmask);
	for (i = 0; i < nintf; i++) {
		if ((addrs[i].flags & INTF_VALID) == 0)
			continue;
		FD_SET(addrs[i].fd, &globmask);
		if (addrs[i].if_flags & IFF_BROADCAST)
			TRACE (2, ("Addr %d: %s fd %d %s broadcast %s",
				   i, addrs[i].name, addrs[i].fd,
				   paddr (&addrs[i].addr),
				   ntoa (&addrs[i].bcast)));
		else
			TRACE (2, ("Addr %d: %s fd %d %s", i,
				   addrs[i].name, addrs[i].fd,
				   paddr (&addrs[i].addr)));
	}

	(void) signal(SIGINT, finish);
	(void) signal(SIGTERM, finish);
#if	defined(DEBUG) && defined(SIGUSR1) && defined(SIGUSR2)
	(void) signal(SIGUSR1, incdebug);
	(void) signal(SIGUSR2, decdebug);
#endif
	/*
	 * Find highest fd in use.  This might save a few microseconds in
	 * the select system call.
	 */
	for (selfds = FD_SETSIZE - 1; selfds; selfds--)
		if (FD_ISSET(selfds, &globmask))
			break;
	TRACE (2, ("Highest fd in use is %d", selfds));
	if (!selfds) abort();
	selfds++;

	/* prime the pump! */
	ticked = 1;
	(void) gettimeofday(&tv, (struct timezone *) 0);

	for (;;) {	/* go into a finite but hopefully very long loop */

		readfds = globmask;
		writefds = globwmask;
		TRACE (7, ("wait nfds %d, fds 0x%x 0x%x", selfds,
			   readfds.fds_bits[0], writefds.fds_bits[0]));

		if (ticked) {
			ticked = 0;
			tvt = tv;
		}

		(void) TNetAcceptAux (&vecp, vec, &newfd, NULLTA,
				      selfds, &readfds,
				      &writefds, NULLFD, (1<<CLOCK_ADJ), td);

		(void) gettimeofday(&tv, (struct timezone *) 0);
		if (tv.tv_sec - tvt.tv_sec >= (1 << CLOCK_ADJ))
			ticked = 1;

		if (vecp > 0)
			iso_init (vecp, vec, newfd);

		for(i = 0; i < nintf; i++) {
			if ((addrs[i].flags & INTF_SELECT) == 0)
				continue;

			if (!FD_ISSET(addrs[i].fd, &readfds) &&
			    !FD_ISSET (addrs[i].fd, &writefds))
				continue;
			TRACE (3, ("Activity on if %d fd=%d (%s)",
				   i, addrs[i].fd, addrs[i].name));
			if (addrs[i].flags & INTF_PENDING) {
				struct ntp_peer *p = find_peer (i);
				if (p)
					(void) make_osi_conn (find_peer(i),
							      osiaddress);
				continue;
			}
			if (addrs[i].flags & INTF_ACCEPTING) {
				(void) iso_accept (&addrs[i]);
				continue;
			}
			addrs[i].uses++;
			switch (addrs[i].addr.type) {
			    case AF_INET:
				if (recv_inet (&addrs[i], &tv) == -1)
					continue;
				break;

			    case AF_OSI:
				if (recv_osi (&addrs[i], &tv) == -1)
					continue;
				break;

			    default:
				TRACE (1, ("Address family %d not supported",
						addrs[i].addr.type));
				continue;
			}
		}
		if (ticked)
			timeout((int) (tv.tv_sec - tvt.tv_sec));
	}
}

struct ntp_peer *
check_peer(dst, sock)
	struct Naddr *dst;
	int sock;
{
	register struct ntp_peer *peer = peer_list.head;

	while (peer != NULL) {
		if (addr_compare (&peer->src, dst) &&
		    ((peer->sock == sock) || (peer->sock == -1)))
			return peer;
		peer = peer->next;
	}
	return ((struct ntp_peer *) NULL);
}

#ifdef	DEBUG
void
dump_pkt(dst, pkt, peer)
	struct Naddr *dst;
	struct ntpdata *pkt;
	struct ntp_peer *peer;
{
	struct Naddr clock_host;

	(void) printf("Packet: %s\n", paddr (dst));

	(void) printf("Leap %d, version %d, mode %d, poll %d, precision %d stratum %d",
	       (int)(pkt->status & LEAPMASK) >> 6, (int)(pkt->status & VERSIONMASK) >> 3,
	       pkt->status & MODEMASK, pkt->ppoll, pkt->precision,
	       pkt->stratum);
	switch (pkt->stratum) {
	case 0:
	case 1:
		(void) printf(" (%.4s)\n", (char *)&pkt->refid);
		break;
	default:
		clock_host.inet_ad.sin_addr.s_addr = (u_long) pkt->refid;
		clock_host.type = AF_INET;
		(void) printf(" [%s]\n", paddr (&clock_host));
		break;
	}
	(void) printf("Synch Dist is %04X.%04X  Synch Dispersion is %04X.%04X\n",
	       ntohs((u_short) pkt->distance.int_part),
	       ntohs((u_short) pkt->distance.fraction),
	       ntohs((u_short) pkt->dispersion.int_part),
	       ntohs((u_short) pkt->dispersion.fraction));
	(void) printf("Reference Timestamp is %08lx.%08lx\n",
	       ntohl(pkt->reftime.int_part),
	       ntohl(pkt->reftime.fraction));
	(void) printf("Originate Timestamp is %08lx.%08lx\n",
	       ntohl(pkt->org.int_part),
	       ntohl(pkt->org.fraction));
	(void) printf("Receive Timestamp is   %08lx.%08lx\n",
	       ntohl(pkt->rec.int_part),
	       ntohl(pkt->rec.fraction));
	(void) printf("Transmit Timestamp is  %08lx.%08lx\n",
	       ntohl(pkt->xmt.int_part),
	       ntohl(pkt->xmt.fraction));
	if(peer != NULL)
		(void) printf("Input Timestamp is     %08lx.%08lx\n",
		       ntohl(peer->rec.int_part),
		       ntohl(peer->rec.fraction));
	(void) putchar('\n');
}
#endif

void
make_new_peer(peer)
	struct ntp_peer *peer;
{
	int i;
	void	double_to_s_fixed ();

	/*
	 * initialize peer data fields 
	 */
	bzero ((char *)peer, sizeof (*peer));
	peer->src.type = peer->src.inet_ad.sin_family = AF_INET;
	peer->hmode = MODE_SYM_PAS;	/* default: symmetric passive mode */
	peer->timer = 1 << NTP_MINPOLL;
	peer->hpoll = NTP_MINPOLL;
	peer->ppoll = NTP_MAXPOLL;
	peer->vers = 2;
	peer->mode = 0;
	double_to_s_fixed(&peer->dispersion, PEER_MAXDISP);
	peer->estoffset = 0.0;
	peer->estdelay = 0.0;
	for (i = 0; i < NTP_WINDOW; i++) {
		peer->filter.offset[i] = 0.0;
		peer->filter.delay[i] = 0.0;
	}
}

/*
 *  This procedure is called to delete a peer from our list of peers.
 */
demobilize(l, peer)
	struct list *l;
	struct ntp_peer *peer;
{
	extern struct ntp_peer dummy_peer;

	if (keepallpeers) {
		peer -> flags |= PEER_FL_SNOOZE;
		return 0;
	}

	if (peer == &dummy_peer)
#ifdef	DEBUG
		abort();
#else
		return 1;
#endif

#ifdef	DEBUG
	if ((peer->next == NULL && peer->prev == NULL) ||
	    l->tail == NULL || l->head == NULL)
		abort();
#endif

	/* delete only peer in list? */
	if (l->head == l->tail) {
#ifdef	DEBUG
		if (l->head != peer) abort();
#endif
		l->head = l->tail = NULL;
		goto dropit;
	}

	/* delete first peer? */
	if (l->head == peer) {
		l->head = peer->next;
		l->head->prev = NULL;
		goto dropit;
	}

	/* delete last peer? */
	if (l->tail == peer) {
		l->tail = peer->prev;
		l->tail->next = NULL;
		goto dropit;
	}

	/* drop peer in middle */
	peer->prev->next = peer->next;
	peer->next->prev = peer->prev;

 dropit:
#ifdef	DEBUG
	/* just some sanity checking */
	if ((l->members < 0) || 
	    (l->members && l->tail == NULL) ||
	    (l->members == 0 && l->tail != NULL)) {
		advise (LLOG_EXCEPTIONS, NULLCP, "List hosed (demobilize)");
		abort();
	}
	peer->next = peer->prev = NULL;
#endif
	free((char *) peer);
	l->members--;

	return 1;
}

enqueue(l, peer)
	register struct list *l;
	struct ntp_peer *peer;
{
	l->members++;
	if (l->tail == NULL) {
		/* insertion into empty list */
		l->tail = l->head = peer;
		peer->next = peer->prev = NULL;
		return;
	}

	/* insert at end of list */
	l->tail->next = peer;
	peer->next = NULL;
	peer->prev = l->tail;
	l->tail = peer;
}