[dragonfly.git] / sbin / dhclient / dispatch.c

/*	$OpenBSD: src/sbin/dhclient/dispatch.c,v 1.52 2012/07/09 16:21:21 krw Exp $	*/

/*
 * Copyright 2004 Henning Brauer <henning@openbsd.org>
 * Copyright (c) 1995, 1996, 1997, 1998, 1999
 * The Internet Software Consortium.   All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of The Internet Software Consortium nor the names
 *    of its contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This software has been written for the Internet Software Consortium
 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
 * Enterprises.  To learn more about the Internet Software Consortium,
 * see ``http://www.vix.com/isc''.  To learn more about Vixie
 * Enterprises, see ``http://www.vix.com''.
 */

#include <sys/ioctl.h>

#include <net/if_media.h>

#include <ifaddrs.h>
#include <poll.h>

#include "dhcpd.h"

struct timeout timeout;
static int interfaces_invalidated;

/*
 * Use getifaddrs() to get a list of all the attached interfaces.  For
 * each interface that's of type INET and not the loopback interface,
 * register that interface with the network I/O software, figure out
 * what subnet it's on, and add it to the list of interfaces.
 */
void
discover_interface(void)
{
	struct ifaddrs *ifap, *ifa;
	struct ifreq *tif;
	int len = IFNAMSIZ + sizeof(struct sockaddr_storage);

	if (getifaddrs(&ifap) != 0)
		error("getifaddrs failed");

	for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
		if ((ifa->ifa_flags & IFF_LOOPBACK) ||
		    (ifa->ifa_flags & IFF_POINTOPOINT) ||
		    (!(ifa->ifa_flags & IFF_UP)))
			continue;

		if (strcmp(ifi->name, ifa->ifa_name))
			continue;

		/*
		 * If we have the capability, extract link information
		 * and record it in a linked list.
		 */
		if (ifa->ifa_addr->sa_family == AF_LINK) {
			struct sockaddr_dl *foo =
			    (struct sockaddr_dl *)ifa->ifa_addr;

			ifi->index = foo->sdl_index;
			ifi->hw_address.hlen = foo->sdl_alen;
			ifi->hw_address.htype = HTYPE_ETHER; /* XXX */
			memcpy(ifi->hw_address.haddr,
			    LLADDR(foo), foo->sdl_alen);
		}
		if (!ifi->ifp) {
			if ((tif = malloc(len)) == NULL)
				error("no space to remember ifp");
			strlcpy(tif->ifr_name, ifa->ifa_name, IFNAMSIZ);
			ifi->ifp = tif;
		}
	}

	if (!ifi->ifp)
		error("%s: not found", ifi->name);

	/* Register the interface... */
	if_register_receive();
	if_register_send();
	freeifaddrs(ifap);
}

void
reinitialize_interface(void)
{
	interfaces_invalidated = 1;
}

/*
 * Wait for packets to come in using poll().  When a packet comes in, call
 * receive_packet to receive the packet and possibly strip hardware addressing
 * information from it, and then call do_packet to try to do something with it.
 */
void
dispatch(void)
{
	int count, to_msec;
	struct pollfd fds[2];
	time_t howlong;
	void (*func)(void);

	do {
		/*
		 * Call expired timeout, and then if there's still
		 * a timeout registered, time out the select call then.
		 */
another:
		if (!ifi)
			error("No interfaces available");

		if (!ifi->linkstat)
			interfaces_invalidated = 0;

		if (timeout.func) {
			time(&cur_time);
			if (timeout.when <= cur_time) {
				func = timeout.func;
				cancel_timeout();
				(*(func))();
				goto another;
			}
			/*
			 * Figure timeout in milliseconds, and check for
			 * potential overflow, so we can cram into an
			 * int for poll, while not polling with a
			 * negative timeout and blocking indefinitely.
			 */
			howlong = timeout.when - cur_time;
			if (howlong > INT_MAX / 1000)
				howlong = INT_MAX / 1000;
			to_msec = howlong * 1000;
		} else
			to_msec = -1;

		/* Set up the descriptors to be polled. */
		if (!ifi || ifi->rfdesc == -1)
			error("No live interface to poll on");

		fds[0].fd = ifi->rfdesc;
		fds[1].fd = routefd; /* Could be -1, which will be ignored. */
		fds[0].events = fds[1].events = POLLIN;

		/* Wait for a packet or a timeout... XXX */
		count = poll(fds, 2, to_msec);

		/* Not likely to be transitory... */
		if (count == -1) {
			if (errno == EAGAIN || errno == EINTR) {
				continue;
			} else
				error("poll: %m");
		}

		if ((fds[0].revents & (POLLIN | POLLHUP))) {
			if (ifi && ifi->linkstat && ifi->rfdesc != -1)
				got_one();
		}
		if ((fds[1].revents & (POLLIN | POLLHUP))) {
			if (ifi && !interfaces_invalidated)
				routehandler();
		}

		interfaces_invalidated = 0;
	} while (1);
}

void
got_one(void)
{
	struct sockaddr_in from;
	struct hardware hfrom;
	struct iaddr ifrom;
	ssize_t result;

	if ((result = receive_packet(&from, &hfrom)) == -1) {
		warning("receive_packet failed on %s: %s", ifi->name,
		    strerror(errno));
		ifi->errors++;
		if ((!interface_status(ifi->name)) ||
		    (ifi->noifmedia && ifi->errors > 20)) {
			/* our interface has gone away. */
			error("Interface %s no longer appears valid.",
			    ifi->name);
		}
		return;
	}
	if (result == 0)
		return;

	ifrom.len = 4;
	memcpy(ifrom.iabuf, &from.sin_addr, ifrom.len);

	do_packet(result, from.sin_port, ifrom, &hfrom);
}

int
interface_link_forceup(char *ifname)
{
	struct ifreq ifr;
	int sock;

	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
		error("Can't create socket");

	memset(&ifr, 0, sizeof(ifr));
	strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
	if (ioctl(sock, SIOCGIFFLAGS, (caddr_t)&ifr) == -1) {
		close(sock);
		return (-1);
	}

	if ((ifr.ifr_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
		ifr.ifr_flags |= IFF_UP;
		if (ioctl(sock, SIOCSIFFLAGS, (caddr_t)&ifr) == -1) {
			close(sock);
			return (-1);
		}
		close(sock);
		return (0);
	}
	close(sock);
	return (1);
}

int
interface_status(char *ifname)
{
	struct ifreq ifr;
	struct ifmediareq ifmr;
	int sock;

	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
		error("Can't create socket");

	/* get interface flags */
	memset(&ifr, 0, sizeof(ifr));
	strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) {
		error("ioctl(SIOCGIFFLAGS) on %s: %m", ifname);
	}

	/*
	 * if one of UP and RUNNING flags is dropped,
	 * the interface is not active.
	 */
	if ((ifr.ifr_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
		goto inactive;

	/* Next, check carrier on the interface, if possible */
	if (ifi->noifmedia)
		goto active;
	memset(&ifmr, 0, sizeof(ifmr));
	strlcpy(ifmr.ifm_name, ifname, sizeof(ifmr.ifm_name));
	if (ioctl(sock, SIOCGIFMEDIA, (caddr_t)&ifmr) == -1) {
		/*
		 * EINVAL or ENOTTY simply means that the interface
		 * does not support the SIOCGIFMEDIA ioctl. We regard it alive.
		 */
#ifdef DEBUG
		if (errno != EINVAL && errno != ENOTTY)
			debug("ioctl(SIOCGIFMEDIA) on %s: %m", ifname);
#endif
		ifi->noifmedia = 1;
		goto active;
	}
	if (ifmr.ifm_status & IFM_AVALID) {
		if (ifmr.ifm_status & IFM_ACTIVE)
			goto active;
		else
			goto inactive;
	}
inactive:
	close(sock);
	return (0);
active:
	close(sock);
	return (1);
}

void
set_timeout(time_t when, void (*where)(void))
{
	timeout.when = when;
	timeout.func = where;
}

void
cancel_timeout(void)
{
	timeout.when = 0;
	timeout.func = NULL;
}
Commit	Line	Data
8d05e1a0	1	/* $OpenBSD: src/sbin/dhclient/dispatch.c,v 1.52 2012/07/09 16:21:21 krw Exp $ */
846204b6 HT	2
	3	/*
	4	* Copyright 2004 Henning Brauer <henning@openbsd.org>
	5	* Copyright (c) 1995, 1996, 1997, 1998, 1999
	6	* The Internet Software Consortium. All rights reserved.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	*
	12	* 1. Redistributions of source code must retain the above copyright
	13	* notice, this list of conditions and the following disclaimer.
	14	* 2. Redistributions in binary form must reproduce the above copyright
	15	* notice, this list of conditions and the following disclaimer in the
	16	* documentation and/or other materials provided with the distribution.
	17	* 3. Neither the name of The Internet Software Consortium nor the names
	18	* of its contributors may be used to endorse or promote products derived
	19	* from this software without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
	22	* CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
	23	* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	24	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	25	* DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
	26	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	27	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	28	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	29	* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	30	* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	31	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	32	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	33	* SUCH DAMAGE.
	34	*
	35	* This software has been written for the Internet Software Consortium
	36	* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
	37	* Enterprises. To learn more about the Internet Software Consortium,
	38	* see ``http://www.vix.com/isc''. To learn more about Vixie
	39	* Enterprises, see ``http://www.vix.com''.
	40	*/
	41
	42	#include <sys/ioctl.h>
	43
	44	#include <net/if_media.h>
	45
	46	#include <ifaddrs.h>
	47	#include <poll.h>
	48
	49	#include "dhcpd.h"
	50
8d05e1a0	51	struct timeout timeout;
846204b6 HT	52	static int interfaces_invalidated;
	53
	54	/*
	55	* Use getifaddrs() to get a list of all the attached interfaces. For
	56	* each interface that's of type INET and not the loopback interface,
	57	* register that interface with the network I/O software, figure out
	58	* what subnet it's on, and add it to the list of interfaces.
	59	*/
	60	void
	61	discover_interface(void)
	62	{
	63	struct ifaddrs ifap, ifa;
	64	struct ifreq *tif;
	65	int len = IFNAMSIZ + sizeof(struct sockaddr_storage);
	66
	67	if (getifaddrs(&ifap) != 0)
	68	error("getifaddrs failed");
	69
	70	for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
	71	if ((ifa->ifa_flags & IFF_LOOPBACK) \|\|
	72	(ifa->ifa_flags & IFF_POINTOPOINT) \|\|
	73	(!(ifa->ifa_flags & IFF_UP)))
	74	continue;
	75
	76	if (strcmp(ifi->name, ifa->ifa_name))
	77	continue;
	78
	79	/*
	80	* If we have the capability, extract link information
	81	* and record it in a linked list.
	82	*/
	83	if (ifa->ifa_addr->sa_family == AF_LINK) {
	84	struct sockaddr_dl *foo =
	85	(struct sockaddr_dl *)ifa->ifa_addr;
	86
	87	ifi->index = foo->sdl_index;
	88	ifi->hw_address.hlen = foo->sdl_alen;
	89	ifi->hw_address.htype = HTYPE_ETHER; /* XXX */
	90	memcpy(ifi->hw_address.haddr,
	91	LLADDR(foo), foo->sdl_alen);
	92	}
	93	if (!ifi->ifp) {
	94	if ((tif = malloc(len)) == NULL)
	95	error("no space to remember ifp");
	96	strlcpy(tif->ifr_name, ifa->ifa_name, IFNAMSIZ);
	97	ifi->ifp = tif;
	98	}
	99	}
	100
	101	if (!ifi->ifp)
	102	error("%s: not found", ifi->name);
	103
	104	/* Register the interface... */
	105	if_register_receive();
	106	if_register_send();
	107	freeifaddrs(ifap);
	108	}
	109
	110	void
	111	reinitialize_interface(void)
	112	{
	113	interfaces_invalidated = 1;
	114	}
	115
116	/*
117	* Wait for packets to come in using poll(). When a packet comes in, call
118	* receive_packet to receive the packet and possibly strip hardware addressing
119	* information from it, and then call do_packet to try to do something with it.
120	*/
121	void
122	dispatch(void)
123	{
124	int count, to_msec;
125	struct pollfd fds[2];
126	time_t howlong;
8d05e1a0	127	void (*func)(void);
846204b6 HT	128
	129	do {
	130	/*
8d05e1a0	131	* Call expired timeout, and then if there's still
846204b6 HT	132	* a timeout registered, time out the select call then.
	133	*/
	134	another:
d19bab2e AHJ	135	if (!ifi)
	136	error("No interfaces available");
	137
846204b6 HT	138	if (!ifi->linkstat)
	139	interfaces_invalidated = 0;
	140
8d05e1a0 AHJ	141	if (timeout.func) {
	142	time(&cur_time);
	143	if (timeout.when <= cur_time) {
	144	func = timeout.func;
	145	cancel_timeout();
	146	(*(func))();
846204b6 HT	147	goto another;
846204b6 HT	148	}
846204b6 HT	149	/*
	150	* Figure timeout in milliseconds, and check for
	151	* potential overflow, so we can cram into an
	152	* int for poll, while not polling with a
	153	* negative timeout and blocking indefinitely.
	154	*/
8d05e1a0	155	howlong = timeout.when - cur_time;
846204b6 HT	156	if (howlong > INT_MAX / 1000)
	157	howlong = INT_MAX / 1000;
	158	to_msec = howlong * 1000;
	159	} else
	160	to_msec = -1;
	161
	162	/* Set up the descriptors to be polled. */
	163	if (!ifi \|\| ifi->rfdesc == -1)
	164	error("No live interface to poll on");
	165
	166	fds[0].fd = ifi->rfdesc;
	167	fds[1].fd = routefd; /* Could be -1, which will be ignored. */
	168	fds[0].events = fds[1].events = POLLIN;
	169
	170	/* Wait for a packet or a timeout... XXX */
	171	count = poll(fds, 2, to_msec);
	172
846204b6 HT	173	/* Not likely to be transitory... */
	174	if (count == -1) {
	175	if (errno == EAGAIN \|\| errno == EINTR) {
	176	continue;
	177	} else
	178	error("poll: %m");
	179	}
	180
	181	if ((fds[0].revents & (POLLIN \| POLLHUP))) {
bdf60627	182	if (ifi && ifi->linkstat && ifi->rfdesc != -1)
846204b6 HT	183	got_one();
	184	}
	185	if ((fds[1].revents & (POLLIN \| POLLHUP))) {
	186	if (ifi && !interfaces_invalidated)
	187	routehandler();
	188	}
	189
	190	interfaces_invalidated = 0;
	191	} while (1);
	192	}
	193
	194	void
	195	got_one(void)
	196	{
	197	struct sockaddr_in from;
	198	struct hardware hfrom;
	199	struct iaddr ifrom;
	200	ssize_t result;
	201
	202	if ((result = receive_packet(&from, &hfrom)) == -1) {
	203	warning("receive_packet failed on %s: %s", ifi->name,
	204	strerror(errno));
	205	ifi->errors++;
	206	if ((!interface_status(ifi->name)) \|\|
	207	(ifi->noifmedia && ifi->errors > 20)) {
	208	/* our interface has gone away. */
9930e9a8	209	error("Interface %s no longer appears valid.",
846204b6	210	ifi->name);
846204b6 HT	211	}
	212	return;
	213	}
	214	if (result == 0)
	215	return;
	216
	217	ifrom.len = 4;
	218	memcpy(ifrom.iabuf, &from.sin_addr, ifrom.len);
	219
	220	do_packet(result, from.sin_port, ifrom, &hfrom);
	221	}
	222
	223	int
	224	interface_link_forceup(char *ifname)
	225	{
	226	struct ifreq ifr;
	227	int sock;
	228
	229	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
	230	error("Can't create socket");
	231
	232	memset(&ifr, 0, sizeof(ifr));
	233	strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
	234	if (ioctl(sock, SIOCGIFFLAGS, (caddr_t)&ifr) == -1) {
	235	close(sock);
	236	return (-1);
	237	}
	238
	239	if ((ifr.ifr_flags & (IFF_UP\|IFF_RUNNING)) != (IFF_UP\|IFF_RUNNING)) {
	240	ifr.ifr_flags \|= IFF_UP;
	241	if (ioctl(sock, SIOCSIFFLAGS, (caddr_t)&ifr) == -1) {
	242	close(sock);
	243	return (-1);
	244	}
	245	close(sock);
	246	return (0);
	247	}
	248	close(sock);
	249	return (1);
	250	}
	251
846204b6 HT	252	int
	253	interface_status(char *ifname)
	254	{
	255	struct ifreq ifr;
	256	struct ifmediareq ifmr;
	257	int sock;
	258
	259	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
	260	error("Can't create socket");
	261
	262	/* get interface flags */
	263	memset(&ifr, 0, sizeof(ifr));
	264	strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
f6c633e7	265	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) {
9930e9a8	266	error("ioctl(SIOCGIFFLAGS) on %s: %m", ifname);
846204b6 HT	267	}
	268
	269	/*
	270	* if one of UP and RUNNING flags is dropped,
	271	* the interface is not active.
	272	*/
	273	if ((ifr.ifr_flags & (IFF_UP\|IFF_RUNNING)) != (IFF_UP\|IFF_RUNNING))
	274	goto inactive;
	275
	276	/* Next, check carrier on the interface, if possible */
	277	if (ifi->noifmedia)
	278	goto active;
	279	memset(&ifmr, 0, sizeof(ifmr));
	280	strlcpy(ifmr.ifm_name, ifname, sizeof(ifmr.ifm_name));
f6c633e7	281	if (ioctl(sock, SIOCGIFMEDIA, (caddr_t)&ifmr) == -1) {
846204b6 HT	282	/*
	283	* EINVAL or ENOTTY simply means that the interface
	284	* does not support the SIOCGIFMEDIA ioctl. We regard it alive.
	285	*/
4cada237	286	#ifdef DEBUG
846204b6 HT	287	if (errno != EINVAL && errno != ENOTTY)
846204b6 HT	288	debug("ioctl(SIOCGIFMEDIA) on %s: %m", ifname);
4cada237	289	#endif
846204b6 HT	290	ifi->noifmedia = 1;
	291	goto active;
	292	}
	293	if (ifmr.ifm_status & IFM_AVALID) {
	294	if (ifmr.ifm_status & IFM_ACTIVE)
	295	goto active;
	296	else
	297	goto inactive;
	298	}
	299	inactive:
	300	close(sock);
	301	return (0);
	302	active:
	303	close(sock);
	304	return (1);
	305	}
	306
	307	void
8d05e1a0	308	set_timeout(time_t when, void (*where)(void))
846204b6	309	{
8d05e1a0 AHJ	310	timeout.when = when;
8d05e1a0 AHJ	311	timeout.func = where;
846204b6 HT	312	}
	313
	314	void
8d05e1a0	315	cancel_timeout(void)
846204b6	316	{
8d05e1a0 AHJ	317	timeout.when = 0;
8d05e1a0 AHJ	318	timeout.func = NULL;
846204b6	319	}