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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/dhcrelay6/dispatch.c	Lines:	0	183	0.0 %
Date:	2017-11-13	Branches:	0	130	0.0 %


/*	$OpenBSD: dispatch.c,v 1.1 2017/03/17 14:45:16 rzalamena 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/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>

#include <netinet/in.h>
#include <netinet/if_ether.h>

#include <errno.h>
#include <ifaddrs.h>
#include <limits.h>
#include <poll.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>

#include "dhcp.h"
#include "dhcpd.h"
#include "log.h"

/*
 * Macros implementation used to generate link-local addresses. This
 * code was copied from: sys/netinet6/in6_ifattach.c.
 */
#define EUI64_UBIT		0x02
#define EUI64_TO_IFID(in6) \
	do { (in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)

struct protocol *protocols;
struct timeout *timeouts;
static struct timeout *free_timeouts;
static int interfaces_invalidated;

void (*bootp_packet_handler)(struct interface_info *,
    void *, size_t, struct packet_ctx *);

static int interface_status(struct interface_info *ifinfo);

struct interface_info *
iflist_getbyindex(unsigned int index)
{
	struct interface_info	*intf;

	TAILQ_FOREACH(intf, &intflist, entry) {
		if (intf->index != index)
			continue;

		return intf;
	}

	return NULL;
}

struct interface_info *
iflist_getbyname(const char *name)
{
	struct interface_info	*intf;

	TAILQ_FOREACH(intf, &intflist, entry) {
		if (strcmp(intf->name, name) != 0)
			continue;

		return intf;
	}

	return NULL;
}

struct interface_info *
iflist_getbyaddr6(struct in6_addr *addr)
{
	struct interface_info	*intf;

	TAILQ_FOREACH(intf, &intflist, entry) {
		/* Look for link-layer address. */
		if (memcmp(&intf->linklocal, addr, sizeof(*addr)) == 0)
			return intf;
	}

	return NULL;
}

void
setup_iflist(void)
{
	struct interface_info		*intf;
	struct sockaddr_dl		*sdl;
	struct ifaddrs			*ifap, *ifa;
	struct if_data			*ifi;
	struct sockaddr_in		*sin;
	struct sockaddr_in6		*sin6;

	TAILQ_INIT(&intflist);
	if (getifaddrs(&ifap))
		fatalx("getifaddrs failed");

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

		/* Find interface or create it. */
		intf = iflist_getbyname(ifa->ifa_name);
		if (intf == NULL) {
			intf = calloc(1, sizeof(*intf));
			if (intf == NULL)
				fatal("calloc");

			strlcpy(intf->name, ifa->ifa_name,
			    sizeof(intf->name));
			TAILQ_INSERT_HEAD(&intflist, intf, entry);
		}

		/* Signal disabled interface. */
		if ((ifa->ifa_flags & IFF_UP) == 0)
			intf->dead = 1;

		if (ifa->ifa_addr->sa_family == AF_LINK) {
			sdl = (struct sockaddr_dl *)ifa->ifa_addr;
			ifi = (struct if_data *)ifa->ifa_data;

			/* Skip non ethernet interfaces. */
			if (ifi->ifi_type != IFT_ETHER &&
			    ifi->ifi_type != IFT_ENC) {
				TAILQ_REMOVE(&intflist, intf, entry);
				free(intf);
				continue;
			}

			intf->index = sdl->sdl_index;
			intf->hw_address.hlen = sdl->sdl_alen;
			memcpy(intf->hw_address.haddr,
			    LLADDR(sdl), sdl->sdl_alen);
		} else if (ifa->ifa_addr->sa_family == AF_INET) {
			sin = (struct sockaddr_in *)ifa->ifa_addr;
			if (sin->sin_addr.s_addr == htonl(INADDR_LOOPBACK) ||
			    intf->primary_address.s_addr != INADDR_ANY)
				continue;

			intf->primary_address = sin->sin_addr;
		} else if (ifa->ifa_addr->sa_family == AF_INET6) {
			sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
			/* Remove the scope from address if link-local. */
			if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
				intf->linklocal = sin6->sin6_addr;
				intf->linklocal.s6_addr[2] = 0;
				intf->linklocal.s6_addr[3] = 0;
			} else
				intf->gipv6 = 1;

			/* At least one IPv6 address was found. */
			intf->ipv6 = 1;
		}
	}

	freeifaddrs(ifap);

	/*
	 * Generate link-local IPv6 address for interfaces without it.
	 *
	 * For IPv6 DHCP Relay it doesn't matter what is used for
	 * link-addr field, so let's generate an address that won't
	 * change during execution so we can always find the interface
	 * to relay packets back. This is only used for layer 2 relaying
	 * when the interface might not have an address.
	 */
	TAILQ_FOREACH(intf, &intflist, entry) {
		if (memcmp(&intf->linklocal, &in6addr_any,
		    sizeof(in6addr_any)) != 0)
			continue;

		intf->linklocal.s6_addr[0] = 0xfe;
		intf->linklocal.s6_addr[1] = 0x80;
		intf->linklocal.s6_addr[8] = intf->hw_address.haddr[0];
		intf->linklocal.s6_addr[9] = intf->hw_address.haddr[1];
		intf->linklocal.s6_addr[10] = intf->hw_address.haddr[2];
		intf->linklocal.s6_addr[11] = 0xff;
		intf->linklocal.s6_addr[12] = 0xfe;
		intf->linklocal.s6_addr[13] = intf->hw_address.haddr[3];
		intf->linklocal.s6_addr[14] = intf->hw_address.haddr[4];
		intf->linklocal.s6_addr[15] = intf->hw_address.haddr[5];
		EUI64_TO_IFID(&intf->linklocal);
	}
}

struct interface_info *
register_interface(const char *ifname, void (*handler)(struct protocol *))
{
	struct interface_info		*intf;

	if ((intf = iflist_getbyname(ifname)) == NULL)
		return NULL;

	/* Don't register disabled interfaces. */
	if (intf->dead)
		return NULL;

	/* Check if we already registered the interface. */
	if (intf->ifr.ifr_name[0] != 0)
		return intf;

	if (strlcpy(intf->ifr.ifr_name, ifname,
	    sizeof(intf->ifr.ifr_name)) >= sizeof(intf->ifr.ifr_name))
		fatalx("interface name '%s' too long", ifname);

	if_register_receive(intf);
	if_register_send(intf);
	add_protocol(intf->name, intf->rfdesc, handler, intf);

	return intf;
}

/*
 * 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 through the
 * bootp_packet_handler hook to try to do something with it.
 */
void
dispatch(void)
{
	int count, i, to_msec, nfds = 0;
	struct protocol *l;
	struct pollfd *fds;
	time_t howlong;

	nfds = 0;
	for (l = protocols; l; l = l->next)
		nfds++;

	fds = calloc(nfds, sizeof(struct pollfd));
	if (fds == NULL)
		fatalx("Can't allocate poll structures.");

	do {
		/*
		 * Call any expired timeouts, and then if there's still
		 * a timeout registered, time out the select call then.
		 */
another:
		if (timeouts) {
			if (timeouts->when <= cur_time) {
				struct timeout *t = timeouts;

				timeouts = timeouts->next;
				(*(t->func))(t->what);
				t->next = free_timeouts;
				free_timeouts = t;
				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 = timeouts->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. */
		i = 0;

		for (l = protocols; l; l = l->next) {
			struct interface_info *ip = l->local;

			if (ip && (l->handler != got_one || !ip->dead)) {
				fds[i].fd = l->fd;
				fds[i].events = POLLIN;
				fds[i].revents = 0;
				i++;
			}
		}

		if (i == 0)
			fatalx("No live interfaces to poll on - exiting.");

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

		/* Not likely to be transitory... */
		if (count == -1) {
			if (errno == EAGAIN || errno == EINTR) {
				time(&cur_time);
				continue;
			}
			else
				fatal("poll");
		}

		/* Get the current time... */
		time(&cur_time);

		i = 0;
		for (l = protocols; l; l = l->next) {
			struct interface_info *ip = l->local;

			if ((fds[i].revents & (POLLIN | POLLHUP))) {
				fds[i].revents = 0;
				if (ip && (l->handler != got_one ||
				    !ip->dead))
					(*(l->handler))(l);
				if (interfaces_invalidated)
					break;
			}
			i++;
		}
		interfaces_invalidated = 0;
	} while (1);
}


void
got_one(struct protocol *l)
{
	struct packet_ctx pc;
	ssize_t result;
	uint8_t buf[4096];
	struct interface_info *ip = l->local;

	memset(&pc, 0, sizeof(pc));

	if ((result = receive_packet(ip, buf, sizeof(buf), &pc)) == -1) {
		log_warn("receive_packet failed on %s", ip->name);
		ip->errors++;
		if ((!interface_status(ip)) ||
		    (ip->noifmedia && ip->errors > 20)) {
			/* our interface has gone away. */
			log_warnx("Interface %s no longer appears valid.",
			    ip->name);
			ip->dead = 1;
			interfaces_invalidated = 1;
			close(l->fd);
			remove_protocol(l);
			free(ip);
		}
		return;
	}
	if (result == 0)
		return;

	if (bootp_packet_handler)
		(*bootp_packet_handler)(ip, buf, result, &pc);
}

int
interface_status(struct interface_info *ifinfo)
{
	char *ifname = ifinfo->name;
	int ifsock = ifinfo->rfdesc;
	struct ifreq ifr;
	struct ifmediareq ifmr;

	/* get interface flags */
	memset(&ifr, 0, sizeof(ifr));
	strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
	if (ioctl(ifsock, SIOCGIFFLAGS, &ifr) == -1) {
		log_warn("ioctl(SIOCGIFFLAGS) on %s", ifname);
		goto inactive;
	}
	/*
	 * 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 (ifinfo->noifmedia)
		goto active;
	memset(&ifmr, 0, sizeof(ifmr));
	strlcpy(ifmr.ifm_name, ifname, sizeof(ifmr.ifm_name));
	if (ioctl(ifsock, SIOCGIFMEDIA, (caddr_t)&ifmr) == -1) {
		if (errno != EINVAL) {
			log_debug("ioctl(SIOCGIFMEDIA) on %s", ifname);
			ifinfo->noifmedia = 1;
			goto active;
		}
		/*
		 * EINVAL (or ENOTTY) simply means that the interface
		 * does not support the SIOCGIFMEDIA ioctl. We regard it alive.
		 */
		ifinfo->noifmedia = 1;
		goto active;
	}
	if (ifmr.ifm_status & IFM_AVALID) {
		switch (ifmr.ifm_active & IFM_NMASK) {
		case IFM_ETHER:
			if (ifmr.ifm_status & IFM_ACTIVE)
				goto active;
			else
				goto inactive;
			break;
		default:
			goto inactive;
		}
	}
inactive:
	return (0);
active:
	return (1);
}

/* Add a protocol to the list of protocols... */
void
add_protocol(char *name, int fd, void (*handler)(struct protocol *),
    void *local)
{
	struct protocol *p;

	p = malloc(sizeof(*p));
	if (!p)
		fatalx("can't allocate protocol struct for %s", name);

	p->fd = fd;
	p->handler = handler;
	p->local = local;
	p->next = protocols;
	protocols = p;
}

void
remove_protocol(struct protocol *proto)
{
	struct protocol *p, *next, *prev;

	prev = NULL;
	for (p = protocols; p; p = next) {
		next = p->next;
		if (p == proto) {
			if (prev)
				prev->next = p->next;
			else
				protocols = p->next;
			free(p);
		}
	}
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: dispatch.c,v 1.1 2017/03/17 14:45:16 rzalamena Exp $ */
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/types.h>
43			#include <sys/ioctl.h>
44			#include <sys/socket.h>
45
46			#include <net/if.h>
47			#include <net/if_dl.h>
48			#include <net/if_media.h>
49			#include <net/if_types.h>
50
51			#include <netinet/in.h>
52			#include <netinet/if_ether.h>
53
54			#include <errno.h>
55			#include <ifaddrs.h>
56			#include <limits.h>
57			#include <poll.h>
58			#include <stdlib.h>
59			#include <string.h>
60			#include <syslog.h>
61			#include <time.h>
62			#include <unistd.h>
63
64			#include "dhcp.h"
65			#include "dhcpd.h"
66			#include "log.h"
67
68			/*
69			* Macros implementation used to generate link-local addresses. This
70			* code was copied from: sys/netinet6/in6_ifattach.c.
71			*/
72			#define EUI64_UBIT 0x02
73			#define EUI64_TO_IFID(in6) \
74			do { (in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
75
76			struct protocol *protocols;
77			struct timeout *timeouts;
78			static struct timeout *free_timeouts;
79			static int interfaces_invalidated;
80
81			void (bootp_packet_handler)(struct interface_info ,
82			void , size_t, struct packet_ctx );
83
84			static int interface_status(struct interface_info *ifinfo);
85
86			struct interface_info *
87			iflist_getbyindex(unsigned int index)
88			{
89			struct interface_info *intf;
90
91			TAILQ_FOREACH(intf, &intflist, entry) {
92			if (intf->index != index)
93			continue;
94
95			return intf;
96			}
97
98			return NULL;
99			}
100
101			struct interface_info *
102			iflist_getbyname(const char *name)
103			{
104			struct interface_info *intf;
105
106			TAILQ_FOREACH(intf, &intflist, entry) {
107			if (strcmp(intf->name, name) != 0)
108			continue;
109
110			return intf;
111			}
112
113			return NULL;
114			}
115
116			struct interface_info *
117			iflist_getbyaddr6(struct in6_addr *addr)
118			{
119			struct interface_info *intf;
120
121			TAILQ_FOREACH(intf, &intflist, entry) {
122			/* Look for link-layer address. */
123			if (memcmp(&intf->linklocal, addr, sizeof(*addr)) == 0)
124			return intf;
125			}
126
127			return NULL;
128			}
129
130			void
131			setup_iflist(void)
132			{
133			struct interface_info *intf;
134			struct sockaddr_dl *sdl;
135			struct ifaddrs ifap, ifa;
136			struct if_data *ifi;
137			struct sockaddr_in *sin;
138			struct sockaddr_in6 *sin6;
139
140			TAILQ_INIT(&intflist);
141			if (getifaddrs(&ifap))
142			fatalx("getifaddrs failed");
143
144			for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
145			if ((ifa->ifa_flags & IFF_LOOPBACK) \|\|
146			(ifa->ifa_flags & IFF_POINTOPOINT))
147			continue;
148
149			/* Find interface or create it. */
150			intf = iflist_getbyname(ifa->ifa_name);
151			if (intf == NULL) {
152			intf = calloc(1, sizeof(*intf));
153			if (intf == NULL)
154			fatal("calloc");
155
156			strlcpy(intf->name, ifa->ifa_name,
157			sizeof(intf->name));
158			TAILQ_INSERT_HEAD(&intflist, intf, entry);
159			}
160
161			/* Signal disabled interface. */
162			if ((ifa->ifa_flags & IFF_UP) == 0)
163			intf->dead = 1;
164
165			if (ifa->ifa_addr->sa_family == AF_LINK) {
166			sdl = (struct sockaddr_dl *)ifa->ifa_addr;
167			ifi = (struct if_data *)ifa->ifa_data;
168
169			/* Skip non ethernet interfaces. */
170			if (ifi->ifi_type != IFT_ETHER &&
171			ifi->ifi_type != IFT_ENC) {
172			TAILQ_REMOVE(&intflist, intf, entry);
173			free(intf);
174			continue;
175			}
176
177			intf->index = sdl->sdl_index;
178			intf->hw_address.hlen = sdl->sdl_alen;
179			memcpy(intf->hw_address.haddr,
180			LLADDR(sdl), sdl->sdl_alen);
181			} else if (ifa->ifa_addr->sa_family == AF_INET) {
182			sin = (struct sockaddr_in *)ifa->ifa_addr;
183			if (sin->sin_addr.s_addr == htonl(INADDR_LOOPBACK) \|\|
184			intf->primary_address.s_addr != INADDR_ANY)
185			continue;
186
187			intf->primary_address = sin->sin_addr;
188			} else if (ifa->ifa_addr->sa_family == AF_INET6) {
189			sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
190			/* Remove the scope from address if link-local. */
191			if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
192			intf->linklocal = sin6->sin6_addr;
193			intf->linklocal.s6_addr[2] = 0;
194			intf->linklocal.s6_addr[3] = 0;
195			} else
196			intf->gipv6 = 1;
197
198			/* At least one IPv6 address was found. */
199			intf->ipv6 = 1;
200			}
201			}
202
203			freeifaddrs(ifap);
204
205			/*
206			* Generate link-local IPv6 address for interfaces without it.
207			*
208			* For IPv6 DHCP Relay it doesn't matter what is used for
209			* link-addr field, so let's generate an address that won't
210			* change during execution so we can always find the interface
211			* to relay packets back. This is only used for layer 2 relaying
212			* when the interface might not have an address.
213			*/
214			TAILQ_FOREACH(intf, &intflist, entry) {
215			if (memcmp(&intf->linklocal, &in6addr_any,
216			sizeof(in6addr_any)) != 0)
217			continue;
218
219			intf->linklocal.s6_addr[0] = 0xfe;
220			intf->linklocal.s6_addr[1] = 0x80;
221			intf->linklocal.s6_addr[8] = intf->hw_address.haddr[0];
222			intf->linklocal.s6_addr[9] = intf->hw_address.haddr[1];
223			intf->linklocal.s6_addr[10] = intf->hw_address.haddr[2];
224			intf->linklocal.s6_addr[11] = 0xff;
225			intf->linklocal.s6_addr[12] = 0xfe;
226			intf->linklocal.s6_addr[13] = intf->hw_address.haddr[3];
227			intf->linklocal.s6_addr[14] = intf->hw_address.haddr[4];
228			intf->linklocal.s6_addr[15] = intf->hw_address.haddr[5];
229			EUI64_TO_IFID(&intf->linklocal);
230			}
231			}
232
233			struct interface_info *
234			register_interface(const char ifname, void (handler)(struct protocol *))
235			{
236			struct interface_info *intf;
237
238			if ((intf = iflist_getbyname(ifname)) == NULL)
239			return NULL;
240
241			/* Don't register disabled interfaces. */
242			if (intf->dead)
243			return NULL;
244
245			/* Check if we already registered the interface. */
246			if (intf->ifr.ifr_name[0] != 0)
247			return intf;
248
249			if (strlcpy(intf->ifr.ifr_name, ifname,
250			sizeof(intf->ifr.ifr_name)) >= sizeof(intf->ifr.ifr_name))
251			fatalx("interface name '%s' too long", ifname);
252
253			if_register_receive(intf);
254			if_register_send(intf);
255			add_protocol(intf->name, intf->rfdesc, handler, intf);
256
257			return intf;
258			}
259
260			/*
261			* Wait for packets to come in using poll(). When a packet comes in,
262			* call receive_packet to receive the packet and possibly strip hardware
263			* addressing information from it, and then call through the
264			* bootp_packet_handler hook to try to do something with it.
265			*/
266			void
267			dispatch(void)
268			{
269			int count, i, to_msec, nfds = 0;
270			struct protocol *l;
271			struct pollfd *fds;
272			time_t howlong;
273
274			nfds = 0;
275			for (l = protocols; l; l = l->next)
276			nfds++;
277
278			fds = calloc(nfds, sizeof(struct pollfd));
279			if (fds == NULL)
280			fatalx("Can't allocate poll structures.");
281
282			do {
283			/*
284			* Call any expired timeouts, and then if there's still
285			* a timeout registered, time out the select call then.
286			*/
287			another:
288			if (timeouts) {
289			if (timeouts->when <= cur_time) {
290			struct timeout *t = timeouts;
291
292			timeouts = timeouts->next;
293			(*(t->func))(t->what);
294			t->next = free_timeouts;
295			free_timeouts = t;
296			goto another;
297			}
298
299			/*
300			* Figure timeout in milliseconds, and check for
301			* potential overflow, so we can cram into an
302			* int for poll, while not polling with a
303			* negative timeout and blocking indefinitely.
304			*/
305			howlong = timeouts->when - cur_time;
306			if (howlong > INT_MAX / 1000)
307			howlong = INT_MAX / 1000;
308			to_msec = howlong * 1000;
309			} else
310			to_msec = -1;
311
312			/* Set up the descriptors to be polled. */
313			i = 0;
314
315			for (l = protocols; l; l = l->next) {
316			struct interface_info *ip = l->local;
317
318			if (ip && (l->handler != got_one \|\| !ip->dead)) {
319			fds[i].fd = l->fd;
320			fds[i].events = POLLIN;
321			fds[i].revents = 0;
322			i++;
323			}
324			}
325
326			if (i == 0)
327			fatalx("No live interfaces to poll on - exiting.");
328
329			/* Wait for a packet or a timeout... XXX */
330			count = poll(fds, nfds, to_msec);
331
332			/* Not likely to be transitory... */
333			if (count == -1) {
334			if (errno == EAGAIN \|\| errno == EINTR) {
335			time(&cur_time);
336			continue;
337			}
338			else
339			fatal("poll");
340			}
341
342			/* Get the current time... */
343			time(&cur_time);
344
345			i = 0;
346			for (l = protocols; l; l = l->next) {
347			struct interface_info *ip = l->local;
348
349			if ((fds[i].revents & (POLLIN \| POLLHUP))) {
350			fds[i].revents = 0;
351			if (ip && (l->handler != got_one \|\|
352			!ip->dead))
353			(*(l->handler))(l);
354			if (interfaces_invalidated)
355			break;
356			}
357			i++;
358			}
359			interfaces_invalidated = 0;
360			} while (1);
361			}
362
363
364			void
365			got_one(struct protocol *l)
366			{
367			struct packet_ctx pc;
368			ssize_t result;
369			uint8_t buf[4096];
370			struct interface_info *ip = l->local;
371
372			memset(&pc, 0, sizeof(pc));
373
374			if ((result = receive_packet(ip, buf, sizeof(buf), &pc)) == -1) {
375			log_warn("receive_packet failed on %s", ip->name);
376			ip->errors++;
377			if ((!interface_status(ip)) \|\|
378			(ip->noifmedia && ip->errors > 20)) {
379			/* our interface has gone away. */
380			log_warnx("Interface %s no longer appears valid.",
381			ip->name);
382			ip->dead = 1;
383			interfaces_invalidated = 1;
384			close(l->fd);
385			remove_protocol(l);
386			free(ip);
387			}
388			return;
389			}
390			if (result == 0)
391			return;
392
393			if (bootp_packet_handler)
394			(*bootp_packet_handler)(ip, buf, result, &pc);
395			}
396
397			int
398			interface_status(struct interface_info *ifinfo)
399			{
400			char *ifname = ifinfo->name;
401			int ifsock = ifinfo->rfdesc;
402			struct ifreq ifr;
403			struct ifmediareq ifmr;
404
405			/* get interface flags */
406			memset(&ifr, 0, sizeof(ifr));
407			strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
408			if (ioctl(ifsock, SIOCGIFFLAGS, &ifr) == -1) {
409			log_warn("ioctl(SIOCGIFFLAGS) on %s", ifname);
410			goto inactive;
411			}
412			/*
413			* if one of UP and RUNNING flags is dropped,
414			* the interface is not active.
415			*/
416			if ((ifr.ifr_flags & (IFF_UP\|IFF_RUNNING)) != (IFF_UP\|IFF_RUNNING)) {
417			goto inactive;
418			}
419			/* Next, check carrier on the interface, if possible */
420			if (ifinfo->noifmedia)
421			goto active;
422			memset(&ifmr, 0, sizeof(ifmr));
423			strlcpy(ifmr.ifm_name, ifname, sizeof(ifmr.ifm_name));
424			if (ioctl(ifsock, SIOCGIFMEDIA, (caddr_t)&ifmr) == -1) {
425			if (errno != EINVAL) {
426			log_debug("ioctl(SIOCGIFMEDIA) on %s", ifname);
427			ifinfo->noifmedia = 1;
428			goto active;
429			}
430			/*
431			* EINVAL (or ENOTTY) simply means that the interface
432			* does not support the SIOCGIFMEDIA ioctl. We regard it alive.
433			*/
434			ifinfo->noifmedia = 1;
435			goto active;
436			}
437			if (ifmr.ifm_status & IFM_AVALID) {
438			switch (ifmr.ifm_active & IFM_NMASK) {
439			case IFM_ETHER:
440			if (ifmr.ifm_status & IFM_ACTIVE)
441			goto active;
442			else
443			goto inactive;
444			break;
445			default:
446			goto inactive;
447			}
448			}
449			inactive:
450			return (0);
451			active:
452			return (1);
453			}
454
455			/* Add a protocol to the list of protocols... */
456			void
457			add_protocol(char name, int fd, void (handler)(struct protocol *),
458			void *local)
459			{
460			struct protocol *p;
461
462			p = malloc(sizeof(*p));
463			if (!p)
464			fatalx("can't allocate protocol struct for %s", name);
465
466			p->fd = fd;
467			p->handler = handler;
468			p->local = local;
469			p->next = protocols;
470			protocols = p;
471			}
472
473			void
474			remove_protocol(struct protocol *proto)
475			{
476			struct protocol p, next, *prev;
477
478			prev = NULL;
479			for (p = protocols; p; p = next) {
480			next = p->next;
481			if (p == proto) {
482			if (prev)
483			prev->next = p->next;
484			else
485			protocols = p->next;
486			free(p);
487			}
488			}
489			}