ntp_io.c

网络时间协议NTP 源码 版本v4.2.0b 该源码用于linux平台下

			netsyslog(LOG_ERR,
			"setsockopt IPV6_LEAVE_GROUP failure: %m on socket %d, addr %s for %d(%s)",
			iface->fd, stoa(&iface->sin),
			mreq6.ipv6mr_interface, stoa(maddr));
			return ISC_FALSE;
		}
		break;
#else
		return ISC_FALSE;
#endif	/* INCLUDE_IPV6_MULTICAST_SUPPORT */
	}
	iface->num_mcast--;
	if (iface->num_mcast <= 0) {
		iface->flags &= ~INT_MCASTOPEN;
		modify_addr_in_list(maddr, iface->flags);
	}
	return ISC_TRUE;
}
#endif	/* MCAST */

/*
 * io_setbclient - open the broadcast client sockets
 */
void
io_setbclient(void)
{
#ifdef OPEN_BCAST_SOCKET 
	int i;
	int nif = 0;
	isc_boolean_t jstatus; 
	SOCKET fd;

	set_reuseaddr(1);

	for (i = nwilds; i < ninterfaces; i++) {
		/* use only allowed addresses */
		if (inter_list[i].ignore_packets == ISC_TRUE)
			continue;
		/* Only IPv4 addresses are valid for broadcast */
		if (inter_list[i].sin.ss_family != AF_INET)
			continue;

		/* Is this a broadcast address? */
		if (!(inter_list[i].flags & INT_BROADCAST))
			continue;

		/* Skip the loopback addresses */
		if (inter_list[i].flags & INT_LOOPBACK)
			continue;

		/* Do we already have the broadcast address open? */
		if (inter_list[i].flags & INT_BCASTOPEN)
			continue;

		/*
		 * Try to open the broadcast address
		 */
		inter_list[i].family = AF_INET;
		inter_list[i].bfd = open_socket(&inter_list[i].bcast,
				    INT_BROADCAST, 1, &inter_list[i], i);

		 /*
		 * If we succeeded then we use it otherwise
		 * enable the underlying address
		 */
		if (inter_list[i].bfd == INVALID_SOCKET) {
			fd = inter_list[i].fd;
		}
		else {
			fd = inter_list[i].bfd;
		}

		/* Enable Broadcast on socket */
		jstatus = socket_broadcast_enable(&inter_list[i], fd, &inter_list[i].sin);
		if (jstatus == ISC_TRUE)
		{
			nif++;
			netsyslog(LOG_INFO,"io_setbclient: Opened broadcast client on interface %d, socket: %d",
				i, fd);
		}
	}
	set_reuseaddr(0);
#ifdef DEBUG
	if (debug)
		if (nif > 0)
			printf("io_setbclient: Opened broadcast clients\n");
#endif
		if (nif == 0)
			netsyslog(LOG_ERR, "Unable to listen for broadcasts, no broadcast interfaces available");
#else
	netsyslog(LOG_ERR, "io_setbclient: Broadcast Client disabled by build");
#endif
}

/*
 * io_unsetbclient - close the broadcast client sockets
 */
void
io_unsetbclient(void)
{
#ifdef OPEN_BCAST_SOCKET
	int i;
	isc_boolean_t lstatus;

	for (i = nwilds; i < ninterfaces; i++)
	{
		if (!(inter_list[i].flags & INT_BCASTOPEN))
		    continue;
		lstatus = socket_broadcast_disable(&inter_list[i], i, &inter_list[i].sin);
	}
#endif
}

void
io_multicast_add(
	struct sockaddr_storage addr
	)
{
#ifdef MCAST
	int i;
	isc_boolean_t jstatus;
	int ind;
	int lscope = 0;

	/*
	 * Check to see if this is a multicast address
	 */
	if (addr_ismulticast(&addr) == ISC_FALSE)
		return;

	/* If we already have it we can just return */
	ind = find_flagged_addr_in_list(&addr, INT_MCASTOPEN);
	if (ind >= 0)
	{
		netsyslog(LOG_INFO, "Duplicate request found for multicast address %s",
			stoa(&addr));
		return;
	}

#ifndef MULTICAST_NONEWSOCKET
	/*
	 * Find an empty slot to use
	 */
	ind = -1;
	for (i = nwilds; i < ninterfaces; i++) {
		/* found a free slot */
		if (SOCKNUL(&inter_list[i].sin) &&
		    inter_list[i].fd <= 0 && inter_list[i].bfd <= 0)
		{
			ind = i;
			break;
		}
	}
	/*
	 * We didn't find a slot and nothing available. Log and return
	 */
	if (ind < 0 && ninterfaces >= MAXINTERFACES)
	{
		netsyslog(LOG_ERR,
		"No interface available to use for address %s",
		stoa(&addr));
		return;
	}
	else
	{
		ind = ninterfaces;
	}
	/*
	 * Open a new socket for the multicast address
	 */
	memset((char *)&inter_list[ind], 0, sizeof(struct interface));
	inter_list[ind].sin.ss_family = addr.ss_family;
	inter_list[ind].family = addr.ss_family;

	switch(addr.ss_family) {
	case AF_INET:
		memcpy(&(((struct sockaddr_in *)&inter_list[ind].sin)->sin_addr),
		       &(((struct sockaddr_in*)&addr)->sin_addr),
		       sizeof(struct in_addr));
		((struct sockaddr_in*)&inter_list[ind].sin)->sin_port = htons(NTP_PORT);
		memset(&((struct sockaddr_in*)&inter_list[ind].mask)->sin_addr.s_addr, 0xff, sizeof(struct in_addr));
		break;
	case AF_INET6:
#ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
		memcpy(&(((struct sockaddr_in6 *)&inter_list[ind].sin)->sin6_addr),
		       &((struct sockaddr_in6*)&addr)->sin6_addr,
		       sizeof(struct in6_addr));
		((struct sockaddr_in6*)&inter_list[ind].sin)->sin6_port = htons(NTP_PORT);
#ifdef ISC_PLATFORM_HAVESCOPEID
		((struct sockaddr_in6*)&inter_list[ind].sin)->sin6_scope_id = ((struct sockaddr_in6*)&addr)->sin6_scope_id;
#endif
		memset(&((struct sockaddr_in6*)&inter_list[ind].mask)->sin6_addr.s6_addr, 0xff, sizeof(struct in6_addr));
#endif
		i = findlocalcastinterface(&addr, INT_MULTICAST);
# ifdef ISC_PLATFORM_HAVESCOPEID
		if (i >= 0)
			lscope = ((struct sockaddr_in6*)&inter_list[i].sin)->sin6_scope_id;
# endif
#ifdef DEBUG
	if (debug > 1)
		printf("Found interface index %d, scope: %d for address %s\n",
			i, lscope, stoa(&addr));
#endif
		break;
	}

	set_reuseaddr(1);
	inter_list[ind].bfd = INVALID_SOCKET;
	inter_list[ind].fd = open_socket(&inter_list[ind].sin,
			    INT_MULTICAST, 1, &inter_list[ind], ind);
	set_reuseaddr(0);

	if (inter_list[ind].fd != INVALID_SOCKET)
	{
		inter_list[ind].bfd = INVALID_SOCKET;
		inter_list[ind].ignore_packets = ISC_FALSE;

		(void) strncpy(inter_list[ind].name, "multicast",
			sizeof(inter_list[ind].name));
		((struct sockaddr_in*)&inter_list[ind].mask)->sin_addr.s_addr =
						htonl(~(u_int32)0);
		if (ind >= ninterfaces)
			ninterfaces = ind + 1;
#ifdef DEBUG
		if(debug > 1)
			print_interface(ind);
#endif
	}
	else
	{
		memset((char *)&inter_list[ind], 0, sizeof(struct interface));
		ind = -1;
		if (addr.ss_family == AF_INET)
			ind = wildipv4;
		else if (addr.ss_family == AF_INET6)
			ind = wildipv6;

		if (ind >= 0) {
			/* HACK ! -- stuff in an address */
			inter_list[ind].bcast = addr;
			netsyslog(LOG_ERR,
			 "...multicast address %s using wildcard socket",
			 stoa(&addr));
		} else {
			netsyslog(LOG_ERR,
			"No multicast socket available to use for address %s",
			stoa(&addr));
			return;
		}
	}

#else
	/*
	 * For the case where we can't use a separate socket
	 */
	ind = findlocalcastinterface(&addr, INT_MULTICAST);
#endif
	/*
	 * If we don't have a valid socket, just return
	 */
	if (ind < 0)
	{
		netsyslog(LOG_ERR,
		"Cannot add multicast address %s: Cannot find slot",
		stoa(&addr));
		return;
	}

	jstatus = socket_multicast_enable(&inter_list[ind], ind, lscope, &addr);

	if (jstatus == ISC_TRUE)
		netsyslog(LOG_INFO, "Added Multicast Listener %s on interface %d\n", stoa(&addr), ind);
	else
		netsyslog(LOG_ERR, "Failed to add Multicast Listener %s\n", stoa(&addr));
#else /* MCAST */
	netsyslog(LOG_ERR,
	    "Cannot add multicast address %s: no Multicast support",
	    stoa(&addr));
#endif /* MCAST */
	return;
}

/*
 * io_multicast_del() - delete multicast group address
 */
void
io_multicast_del(
	struct sockaddr_storage addr
	)
{
#ifdef MCAST
	int i;
	isc_boolean_t lstatus;

	/*
	 * Check to see if this is a multicast address
	 */
	if (addr_ismulticast(&addr) == ISC_FALSE)
	{
		netsyslog(LOG_ERR,
			 "invalid multicast address %s", stoa(&addr));
		return;
	}

	switch (addr.ss_family)
	{
	case AF_INET :

		/*
		 * Disable reception of multicast packets
		 */
		i = find_flagged_addr_in_list(&addr, INT_MCASTOPEN);
		while ( i > 0) {
			lstatus = socket_multicast_disable(&inter_list[i], i, &addr);
			i = find_flagged_addr_in_list(&addr, INT_MCASTOPEN);
		}
		break;

#ifdef INCLUDE_IPV6_MULTICAST_SUPPORT
	case AF_INET6 :

		/*
		* Disable reception of multicast packets
		*/
		for (i = 0; i < ninterfaces; i++)
		{
			/* Be sure it's the correct family */
			if (inter_list[i].sin.ss_family != AF_INET6)
				continue;
			if (!(inter_list[i].flags & INT_MCASTOPEN))
				continue;
			if (!(inter_list[i].fd < 0))
				continue;
			if (!SOCKCMP(&addr, &inter_list[i].sin))
				continue;
			lstatus = socket_multicast_disable(&inter_list[i], i, &addr);
		}
		break;
#endif /* INCLUDE_IPV6_MULTICAST_SUPPORT */
	}/* switch */
        delete_addr_from_list(&addr);

#else /* not MCAST */
	netsyslog(LOG_ERR, "this function requires multicast kernel");
#endif /* not MCAST */
}


/*
 * open_socket - open a socket, returning the file descriptor
 */

static SOCKET
open_socket(
	struct sockaddr_storage *addr,
	int flags,
	int turn_off_reuse,
	struct interface *interf,
	int ind
	)
{
	int errval;
	SOCKET fd;
	int on = 1, off = 0;
#if defined(IPTOS_LOWDELAY) && defined(IPPROTO_IP) && defined(IP_TOS)
	int tos;
#endif /* IPTOS_LOWDELAY && IPPROTO_IP && IP_TOS */

	if ((addr->ss_family == AF_INET6) && (isc_net_probeipv6() != ISC_R_SUCCESS))
		return (INVALID_SOCKET);

	/* create a datagram (UDP) socket */
#ifndef SYS_WINNT
	if (  (fd = socket(addr->ss_family, SOCK_DGRAM, 0)) < 0) {
		errval = errno;
#else
	if (  (fd = socket(addr->ss_family, SOCK_DGRAM, 0)) == INVALID_SOCKET) {
		errval = WSAGetLastError();
#endif
		if(addr->ss_family == AF_INET)
			netsyslog(LOG_ERR, "socket(AF_INET, SOCK_DGRAM, 0) failed on address %s: %m",
				stoa(addr));
		else if(addr->ss_family == AF_INET6)
			netsyslog(LOG_ERR, "socket(AF_INET6, SOCK_DGRAM, 0) failed on address %s: %m",
				stoa(addr));
#ifndef SYS_WINNT
		if (errval == EPROTONOSUPPORT || errval == EAFNOSUPPORT ||
		    errval == EPFNOSUPPORT)
#else
		if (errval == WSAEPROTONOSUPPORT || errval == WSAEAFNOSUPPORT ||
		    errval == WSAEPFNOSUPPORT)
#endif
			return (INVALID_SOCKET);
		exit(1);
		/*NOTREACHED*/
	}
#ifdef SYS_WINNT
	if (connection_reset_fix(fd) != ISC_R_SUCCESS) {
		netsyslog(LOG_ERR, "connection_reset_fix(fd) failed on address %s: %m",
			stoa(addr));
	}
#endif /* SYS_WINNT */

	/* set SO_REUSEADDR since we will be binding the same port
	   number on each interface */
	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
		       (char *)&on, sizeof(on)))
	{
		netsyslog(LOG_ERR, "setsockopt SO_REUSEADDR on fails on address %s: %m",
			stoa(addr));
	}

	/*
	 * IPv4 specific options go here
	 */
	if (addr->ss_family == AF_INET) {
#if defined(IPTOS_LOWDELAY) && defined(IPPROTO_IP) && defined(IP_TOS)
	/* set IP_TOS to minimize packet delay */
		tos = IPTOS_LOWDELAY;
		if (setsockopt(fd, IPPROTO_IP, IP_TOS, (char *) &tos, sizeof(tos)) < 0)
		{
			netsyslog(LOG_ERR, "setsockopt IPTOS_LOWDELAY on fails on address %s: %m",
				stoa(addr));
		}
#endif /* IPTOS_LOWDELAY && IPPROTO_IP && IP_TOS */
	}

	/*
	 * IPv6 specific options go here
	 */
        if (addr->ss_family == AF_INET6) {
#if defined(IPV6_V6ONLY)
                if (setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY,
                	(char*)&on, sizeof(on)))
                {
                	netsyslog(LOG_ERR, "setsockopt IPV6_V6ONLY on fails on address %s: %m",
				stoa(addr));
		}
#endif /* IPV6_V6ONLY */
#if defined(IPV6_BINDV6ONLY)
                if (setsockopt(fd, IPPROTO_IPV6, IPV6_BINDV6ONLY,
                	(char*)&on, sizeof(on)))
                {
                	netsyslog(LOG_ERR,
			    "setsockopt IPV6_BINDV6ONLY on fails on address %s: %m",
			    stoa(addr));
		}
#endif /* IPV6_BINDV6ONLY */
	}

	/*
	 * bind the local address.
	 */
	if (bind(fd, (struct sockaddr *)addr, SOCKLEN(addr)) < 0) {
		char buff[160];

		if(addr->ss_family == AF_INET)
			sprintf(buff,
				"bind() fd %d, family %d, port %d, addr %s, in_classd=%d flags=%d fails: %%m",
				fd, addr->ss_family, (int)ntohs(((struct sockaddr_in*)addr)->sin_port),
				stoa(addr),
				IN_CLASSD(ntohl(((struct sockaddr_in*)addr)->sin_addr.s_addr)), flags);
#ifdef INCLUDE_IPV6_SUPPORT
		else if(addr->ss_family == AF_INET6)
		                sprintf(buff,
                                "bind() fd %d, family %d, port %d, scope %d, addr %s, in6_is_addr_multicast=%d flags=%d fails: %%m",
                                fd, addr->ss_family, (int)ntohs(((struct sockaddr_in6*)addr)->sin6_port),
# ifdef ISC_PLATFORM_HAVESCOPEID
                                ((struct sockaddr_in6*)addr)->sin6_scope_id
# else
                                -1
# endif
				, stoa(addr),
                                IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6*)addr)->sin6_addr), flags);
#endif
		else 
			return (INVALID_SOCKET);

		/*
		 * Don't log this under all conditions
		 */
		if (turn_off_reuse == 0 || debug > 1)
			netsyslog(LOG_ERR, buff);

		closesocket(fd);

		return (INVALID_SOCKET);
	}
#ifdef DEBUG
	if (debug)
	    printf("bind() fd %d, family %d, port %d, addr %s, flags=%d\n",
		   fd,
		   addr->ss_family,
		   (int)ntohs(((struct sockaddr_in*)addr)->sin_port),
		   stoa(addr),
		   flags);
#endif

	/*
	 * I/O Completion Ports don't care about the select and FD_SET
	 */
#ifndef HAVE_IO_COMPLETION_PORT
	if (fd > maxactivefd)
	    maxactivefd = fd;
	FD_SET(fd, &activefds);
#endif
	add_socket_to_list(fd);
	add_addr_to_list(addr, ind, interf->flags);
	/*
	 * set non-blocking,
	 */

#ifdef USE_FIONBIO
	/* in vxWorks we use FIONBIO, but the others are defined for old systems, so
	 * all hell breaks loose if we leave them defined
	 */
#undef O_NONBLOCK
#undef FNDELAY
#undef O_NDELAY
#endif

#if defined(O_NONBLOCK) /* POSIX */
	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
	{
		netsyslog(LOG_ERR, "fcntl(O_NONBLOCK) fails on address %s: %m",