xref: /dragonfly/contrib/dhcpcd/src/if.c (revision f984587a)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * dhcpcd - DHCP client daemon
4  * Copyright (c) 2006-2023 Roy Marples <roy@marples.name>
5  * All rights reserved
6 
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/types.h>
31 #include <sys/ioctl.h>
32 #include <sys/socket.h>
33 
34 #include <fcntl.h> /* Needs to be here for old Linux */
35 
36 #include "config.h"
37 
38 #include <net/if.h>
39 #include <net/if_arp.h>
40 #include <netinet/in.h>
41 #ifdef AF_LINK
42 #  include <net/if_dl.h>
43 #  include <net/if_types.h>
44 #  include <netinet/in_var.h>
45 #  undef AF_PACKET	/* Newer Illumos defines this */
46 #endif
47 #ifdef AF_PACKET
48 #  include <netpacket/packet.h>
49 #endif
50 #ifdef SIOCGIFMEDIA
51 #  include <net/if_media.h>
52 #endif
53 #include <net/route.h>
54 
55 #include <ctype.h>
56 #include <errno.h>
57 #include <ifaddrs.h>
58 #include <inttypes.h>
59 #include <fnmatch.h>
60 #include <stddef.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <syslog.h>
65 #include <unistd.h>
66 
67 #define ELOOP_QUEUE	ELOOP_IF
68 #include "common.h"
69 #include "eloop.h"
70 #include "dev.h"
71 #include "dhcp.h"
72 #include "dhcp6.h"
73 #include "if.h"
74 #include "if-options.h"
75 #include "ipv4.h"
76 #include "ipv4ll.h"
77 #include "ipv6nd.h"
78 #include "logerr.h"
79 #include "privsep.h"
80 
81 void
82 if_free(struct interface *ifp)
83 {
84 
85 	if (ifp == NULL)
86 		return;
87 #ifdef IPV4LL
88 	ipv4ll_free(ifp);
89 #endif
90 #ifdef INET
91 	dhcp_free(ifp);
92 	ipv4_free(ifp);
93 #endif
94 #ifdef DHCP6
95 	dhcp6_free(ifp);
96 #endif
97 #ifdef INET6
98 	ipv6nd_free(ifp);
99 	ipv6_free(ifp);
100 #endif
101 	rt_freeif(ifp);
102 	free_options(ifp->ctx, ifp->options);
103 	free(ifp);
104 }
105 
106 int
107 if_opensockets(struct dhcpcd_ctx *ctx)
108 {
109 
110 	if (if_opensockets_os(ctx) == -1)
111 		return -1;
112 
113 #ifdef IFLR_ACTIVE
114 	ctx->pf_link_fd = xsocket(PF_LINK, SOCK_DGRAM | SOCK_CLOEXEC, 0);
115 	if (ctx->pf_link_fd == -1)
116 		return -1;
117 #ifdef HAVE_CAPSICUM
118 	if (ps_rights_limit_ioctl(ctx->pf_link_fd) == -1)
119 		return -1;
120 #endif
121 #endif
122 
123 	/* We use this socket for some operations without INET. */
124 	ctx->pf_inet_fd = xsocket(PF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
125 	if (ctx->pf_inet_fd == -1)
126 		return -1;
127 
128 	return 0;
129 }
130 
131 void
132 if_closesockets(struct dhcpcd_ctx *ctx)
133 {
134 
135 	if (ctx->pf_inet_fd != -1)
136 		close(ctx->pf_inet_fd);
137 #ifdef PF_LINK
138 	if (ctx->pf_link_fd != -1)
139 		close(ctx->pf_link_fd);
140 #endif
141 
142 	if (ctx->priv) {
143 		if_closesockets_os(ctx);
144 		free(ctx->priv);
145 	}
146 }
147 
148 int
149 if_ioctl(struct dhcpcd_ctx *ctx, ioctl_request_t req, void *data, size_t len)
150 {
151 
152 #ifdef PRIVSEP
153 	if (ctx->options & DHCPCD_PRIVSEP)
154 		return (int)ps_root_ioctl(ctx, req, data, len);
155 #endif
156 	return ioctl(ctx->pf_inet_fd, req, data, len);
157 }
158 
159 int
160 if_getflags(struct interface *ifp)
161 {
162 	struct ifreq ifr = { .ifr_flags = 0 };
163 
164 	strlcpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
165 	if (ioctl(ifp->ctx->pf_inet_fd, SIOCGIFFLAGS, &ifr) == -1)
166 		return -1;
167 	ifp->flags = (unsigned int)ifr.ifr_flags;
168 	return 0;
169 }
170 
171 int
172 if_setflag(struct interface *ifp, short setflag, short unsetflag)
173 {
174 	struct ifreq ifr = { .ifr_flags = 0 };
175 	short oflags;
176 
177 	strlcpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
178 	if (ioctl(ifp->ctx->pf_inet_fd, SIOCGIFFLAGS, &ifr) == -1)
179 		return -1;
180 
181 	oflags = ifr.ifr_flags;
182 	ifr.ifr_flags |= setflag;
183 	ifr.ifr_flags &= (short)~unsetflag;
184 	if (ifr.ifr_flags != oflags &&
185 	    if_ioctl(ifp->ctx, SIOCSIFFLAGS, &ifr, sizeof(ifr)) == -1)
186 		return -1;
187 
188 	/*
189 	 * Do NOT set ifp->flags here.
190 	 * We need to listen for flag updates from the kernel as they
191 	 * need to sync with carrier.
192 	 */
193 	return 0;
194 }
195 
196 bool
197 if_is_link_up(const struct interface *ifp)
198 {
199 
200 	return ifp->flags & IFF_UP &&
201 	    (ifp->carrier != LINK_DOWN ||
202 	     (ifp->options != NULL && !(ifp->options->options & DHCPCD_LINK)));
203 }
204 
205 int
206 if_randomisemac(struct interface *ifp)
207 {
208 	uint32_t randnum;
209 	size_t hwlen = ifp->hwlen, rlen = 0;
210 	uint8_t buf[HWADDR_LEN], *bp = buf, *rp = (uint8_t *)&randnum;
211 	char sbuf[HWADDR_LEN * 3];
212 	int retval;
213 
214 	if (hwlen == 0) {
215 		errno = ENOTSUP;
216 		return -1;
217 	}
218 	if (hwlen > sizeof(buf)) {
219 		errno = ENOBUFS;
220 		return -1;
221 	}
222 
223 	for (; hwlen != 0; hwlen--) {
224 		if (rlen == 0) {
225 			randnum = arc4random();
226 			rp = (uint8_t *)&randnum;
227 			rlen = sizeof(randnum);
228 		}
229 		*bp++ = *rp++;
230 		rlen--;
231 	}
232 
233 	/* Unicast address and locally administered. */
234 	buf[0] &= 0xFC;
235 	buf[0] |= 0x02;
236 
237 	logdebugx("%s: hardware address randomised to %s",
238 	    ifp->name,
239 	    hwaddr_ntoa(buf, ifp->hwlen, sbuf, sizeof(sbuf)));
240 	retval = if_setmac(ifp, buf, ifp->hwlen);
241 	if (retval == 0)
242 		memcpy(ifp->hwaddr, buf, ifp->hwlen);
243 	return retval;
244 }
245 
246 static int
247 if_hasconf(struct dhcpcd_ctx *ctx, const char *ifname)
248 {
249 	int i;
250 
251 	for (i = 0; i < ctx->ifcc; i++) {
252 		if (strcmp(ctx->ifcv[i], ifname) == 0)
253 			return 1;
254 	}
255 	return 0;
256 }
257 
258 void
259 if_markaddrsstale(struct if_head *ifs)
260 {
261 	struct interface *ifp;
262 
263 	TAILQ_FOREACH(ifp, ifs, next) {
264 #ifdef INET
265 		ipv4_markaddrsstale(ifp);
266 #endif
267 #ifdef INET6
268 		ipv6_markaddrsstale(ifp, 0);
269 #endif
270 	}
271 }
272 
273 void
274 if_learnaddrs(struct dhcpcd_ctx *ctx, struct if_head *ifs,
275     struct ifaddrs **ifaddrs)
276 {
277 	struct ifaddrs *ifa;
278 	struct interface *ifp;
279 #ifdef INET
280 	const struct sockaddr_in *addr, *net, *brd;
281 #endif
282 #ifdef INET6
283 	struct sockaddr_in6 *sin6, *net6;
284 #endif
285 	int addrflags;
286 
287 	for (ifa = *ifaddrs; ifa; ifa = ifa->ifa_next) {
288 		if (ifa->ifa_addr == NULL)
289 			continue;
290 		if ((ifp = if_find(ifs, ifa->ifa_name)) == NULL)
291 			continue;
292 #ifdef HAVE_IFADDRS_ADDRFLAGS
293 		addrflags = (int)ifa->ifa_addrflags;
294 #endif
295 		switch(ifa->ifa_addr->sa_family) {
296 #ifdef INET
297 		case AF_INET:
298 			addr = (void *)ifa->ifa_addr;
299 			net = (void *)ifa->ifa_netmask;
300 			if (ifa->ifa_flags & IFF_POINTOPOINT)
301 				brd = (void *)ifa->ifa_dstaddr;
302 			else
303 				brd = (void *)ifa->ifa_broadaddr;
304 #ifndef HAVE_IFADDRS_ADDRFLAGS
305 			addrflags = if_addrflags(ifp, &addr->sin_addr,
306 			    ifa->ifa_name);
307 			if (addrflags == -1) {
308 				if (errno != EEXIST && errno != EADDRNOTAVAIL) {
309 					char dbuf[INET_ADDRSTRLEN];
310 					const char *dbp;
311 
312 					dbp = inet_ntop(AF_INET, &addr->sin_addr,
313 					    dbuf, sizeof(dbuf));
314 					logerr("%s: if_addrflags: %s%%%s",
315 					    __func__, dbp, ifp->name);
316 				}
317 				continue;
318 			}
319 #endif
320 			ipv4_handleifa(ctx, RTM_NEWADDR, ifs, ifa->ifa_name,
321 				&addr->sin_addr, &net->sin_addr,
322 				brd ? &brd->sin_addr : NULL, addrflags, 0);
323 			break;
324 #endif
325 #ifdef INET6
326 		case AF_INET6:
327 			sin6 = (void *)ifa->ifa_addr;
328 			net6 = (void *)ifa->ifa_netmask;
329 
330 #ifdef __KAME__
331 			if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr))
332 				/* Remove the scope from the address */
333 				sin6->sin6_addr.s6_addr[2] =
334 				    sin6->sin6_addr.s6_addr[3] = '\0';
335 #endif
336 #ifndef HAVE_IFADDRS_ADDRFLAGS
337 			addrflags = if_addrflags6(ifp, &sin6->sin6_addr,
338 			    ifa->ifa_name);
339 			if (addrflags == -1) {
340 				if (errno != EEXIST && errno != EADDRNOTAVAIL) {
341 					char dbuf[INET6_ADDRSTRLEN];
342 					const char *dbp;
343 
344 					dbp = inet_ntop(AF_INET6, &sin6->sin6_addr,
345 					    dbuf, sizeof(dbuf));
346 					logerr("%s: if_addrflags6: %s%%%s",
347 					    __func__, dbp, ifp->name);
348 				}
349 				continue;
350 			}
351 #endif
352 			ipv6_handleifa(ctx, RTM_NEWADDR, ifs,
353 			    ifa->ifa_name, &sin6->sin6_addr,
354 			    ipv6_prefixlen(&net6->sin6_addr), addrflags, 0);
355 			break;
356 #endif
357 		}
358 	}
359 }
360 
361 void if_freeifaddrs(struct dhcpcd_ctx *ctx, struct ifaddrs **ifaddrs)
362 {
363 #ifndef PRIVSEP_GETIFADDRS
364 	UNUSED(ctx);
365 #endif
366 
367 	if (ifaddrs == NULL)
368 		return;
369 
370 #ifdef PRIVSEP_GETIFADDRS
371 	if (IN_PRIVSEP(ctx))
372 		free(*ifaddrs);
373 	else
374 #endif
375 		freeifaddrs(*ifaddrs);
376 }
377 
378 void
379 if_deletestaleaddrs(struct if_head *ifs)
380 {
381 	struct interface *ifp;
382 
383 	TAILQ_FOREACH(ifp, ifs, next) {
384 #ifdef INET
385 		ipv4_deletestaleaddrs(ifp);
386 #endif
387 #ifdef INET6
388 		ipv6_deletestaleaddrs(ifp);
389 #endif
390 	}
391 }
392 
393 bool
394 if_valid_hwaddr(const uint8_t *hwaddr, size_t hwlen)
395 {
396 	size_t i;
397 	bool all_zeros, all_ones;
398 
399 	all_zeros = all_ones = true;
400 	for (i = 0; i < hwlen; i++) {
401 		if (hwaddr[i] != 0x00)
402 			all_zeros = false;
403 		if (hwaddr[i] != 0xff)
404 			all_ones = false;
405 		if (!all_zeros && !all_ones)
406 			return true;
407 	}
408 	return false;
409 }
410 
411 #if defined(AF_PACKET) && !defined(AF_LINK)
412 static unsigned int
413 if_check_arphrd(struct interface *ifp, unsigned int active, bool if_noconf)
414 {
415 
416 	switch(ifp->hwtype) {
417 	case ARPHRD_ETHER:	/* FALLTHROUGH */
418 	case ARPHRD_IEEE1394:	/* FALLTHROUGH */
419 	case ARPHRD_INFINIBAND:	/* FALLTHROUGH */
420 	case ARPHRD_NONE:	/* FALLTHROUGH */
421 		break;
422 	case ARPHRD_LOOPBACK:
423 	case ARPHRD_PPP:
424 		if (if_noconf && active) {
425 			logdebugx("%s: ignoring due to interface type and"
426 			    " no config",
427 			    ifp->name);
428 			active = IF_INACTIVE;
429 		}
430 		break;
431 	default:
432 		if (active) {
433 			int i;
434 
435 			if (if_noconf)
436 				active = IF_INACTIVE;
437 			i = active ? LOG_WARNING : LOG_DEBUG;
438 			logmessage(i, "%s: unsupported"
439 			    " interface type 0x%.2x",
440 			    ifp->name, ifp->hwtype);
441 		}
442 		break;
443 	}
444 
445 	return active;
446 }
447 #endif
448 
449 struct if_head *
450 if_discover(struct dhcpcd_ctx *ctx, struct ifaddrs **ifaddrs,
451     int argc, char * const *argv)
452 {
453 	struct ifaddrs *ifa;
454 	int i;
455 	unsigned int active;
456 	struct if_head *ifs;
457 	struct interface *ifp;
458 	struct if_spec spec;
459 	bool if_noconf;
460 #ifdef AF_LINK
461 	const struct sockaddr_dl *sdl;
462 #ifdef IFLR_ACTIVE
463 	struct if_laddrreq iflr = { .flags = IFLR_PREFIX };
464 #endif
465 #elif defined(AF_PACKET)
466 	const struct sockaddr_ll *sll;
467 #endif
468 #if defined(SIOCGIFPRIORITY)
469 	struct ifreq ifr;
470 #endif
471 
472 	if ((ifs = malloc(sizeof(*ifs))) == NULL) {
473 		logerr(__func__);
474 		return NULL;
475 	}
476 	TAILQ_INIT(ifs);
477 
478 #ifdef PRIVSEP_GETIFADDRS
479 	if (ctx->options & DHCPCD_PRIVSEP) {
480 		if (ps_root_getifaddrs(ctx, ifaddrs) == -1) {
481 			logerr("ps_root_getifaddrs");
482 			free(ifs);
483 			return NULL;
484 		}
485 	} else
486 #endif
487 	if (getifaddrs(ifaddrs) == -1) {
488 		logerr("getifaddrs");
489 		free(ifs);
490 		return NULL;
491 	}
492 
493 	for (ifa = *ifaddrs; ifa; ifa = ifa->ifa_next) {
494 		if (ifa->ifa_addr != NULL) {
495 #ifdef AF_LINK
496 			if (ifa->ifa_addr->sa_family != AF_LINK)
497 				continue;
498 #elif defined(AF_PACKET)
499 			if (ifa->ifa_addr->sa_family != AF_PACKET)
500 				continue;
501 #endif
502 		}
503 		if (if_nametospec(ifa->ifa_name, &spec) != 0)
504 			continue;
505 
506 		/* It's possible for an interface to have >1 AF_LINK.
507 		 * For our purposes, we use the first one. */
508 		TAILQ_FOREACH(ifp, ifs, next) {
509 			if (strcmp(ifp->name, spec.devname) == 0)
510 				break;
511 		}
512 		if (ifp)
513 			continue;
514 
515 		if (argc > 0) {
516 			for (i = 0; i < argc; i++) {
517 				if (strcmp(argv[i], spec.devname) == 0)
518 					break;
519 			}
520 			active = (i == argc) ? IF_INACTIVE : IF_ACTIVE_USER;
521 		} else {
522 			/* -1 means we're discovering against a specific
523 			 * interface, but we still need the below rules
524 			 * to apply. */
525 			if (argc == -1 && strcmp(argv[0], spec.devname) != 0)
526 				continue;
527 			active = ctx->options & DHCPCD_INACTIVE ?
528 			    IF_INACTIVE: IF_ACTIVE_USER;
529 		}
530 
531 		for (i = 0; i < ctx->ifdc; i++)
532 			if (fnmatch(ctx->ifdv[i], spec.devname, 0) == 0)
533 				break;
534 		if (i < ctx->ifdc)
535 			active = IF_INACTIVE;
536 		for (i = 0; i < ctx->ifc; i++)
537 			if (fnmatch(ctx->ifv[i], spec.devname, 0) == 0)
538 				break;
539 		if (ctx->ifc && i == ctx->ifc)
540 			active = IF_INACTIVE;
541 		for (i = 0; i < ctx->ifac; i++)
542 			if (fnmatch(ctx->ifav[i], spec.devname, 0) == 0)
543 				break;
544 		if (ctx->ifac && i == ctx->ifac)
545 			active = IF_INACTIVE;
546 
547 #ifdef PLUGIN_DEV
548 		/* Ensure that the interface name has settled */
549 		if (!dev_initialised(ctx, spec.devname)) {
550 			logdebugx("%s: waiting for interface to initialise",
551 			    spec.devname);
552 			continue;
553 		}
554 #endif
555 
556 		if (if_vimaster(ctx, spec.devname) == 1) {
557 			int loglevel = argc != 0 ? LOG_ERR : LOG_DEBUG;
558 			logmessage(loglevel,
559 			    "%s: is a Virtual Interface Master, skipping",
560 			    spec.devname);
561 			continue;
562 		}
563 
564 		if_noconf = ((argc == 0 || argc == -1) && ctx->ifac == 0 &&
565 		    !if_hasconf(ctx, spec.devname));
566 
567 		/* Don't allow some reserved interface names unless explicit. */
568 		if (if_noconf && if_ignore(ctx, spec.devname)) {
569 			logdebugx("%s: ignoring due to interface type and"
570 			    " no config", spec.devname);
571 			active = IF_INACTIVE;
572 		}
573 
574 		ifp = calloc(1, sizeof(*ifp));
575 		if (ifp == NULL) {
576 			logerr(__func__);
577 			break;
578 		}
579 		ifp->ctx = ctx;
580 		strlcpy(ifp->name, spec.devname, sizeof(ifp->name));
581 		ifp->flags = ifa->ifa_flags;
582 
583 		if (ifa->ifa_addr != NULL) {
584 #ifdef AF_LINK
585 			sdl = (const void *)ifa->ifa_addr;
586 
587 #ifdef IFLR_ACTIVE
588 			/* We need to check for active address */
589 			strlcpy(iflr.iflr_name, ifp->name,
590 			    sizeof(iflr.iflr_name));
591 			memcpy(&iflr.addr, ifa->ifa_addr,
592 			    MIN(ifa->ifa_addr->sa_len, sizeof(iflr.addr)));
593 			iflr.flags = IFLR_PREFIX;
594 			iflr.prefixlen = (unsigned int)sdl->sdl_alen * NBBY;
595 			if (ioctl(ctx->pf_link_fd, SIOCGLIFADDR, &iflr) == -1 ||
596 			    !(iflr.flags & IFLR_ACTIVE))
597 			{
598 				if_free(ifp);
599 				continue;
600 			}
601 #endif
602 
603 			ifp->index = sdl->sdl_index;
604 			switch(sdl->sdl_type) {
605 #ifdef IFT_BRIDGE
606 			case IFT_BRIDGE: /* FALLTHROUGH */
607 #endif
608 #ifdef IFT_PROPVIRTUAL
609 			case IFT_PROPVIRTUAL: /* FALLTHROUGH */
610 #endif
611 #ifdef IFT_TUNNEL
612 			case IFT_TUNNEL: /* FALLTHROUGH */
613 #endif
614 			case IFT_LOOP: /* FALLTHROUGH */
615 			case IFT_PPP:
616 				/* Don't allow unless explicit */
617 				if (if_noconf && active) {
618 					logdebugx("%s: ignoring due to"
619 					    " interface type and"
620 					    " no config",
621 					    ifp->name);
622 					active = IF_INACTIVE;
623 				}
624 				__fallthrough; /* appease gcc */
625 				/* FALLTHROUGH */
626 #ifdef IFT_L2VLAN
627 			case IFT_L2VLAN: /* FALLTHROUGH */
628 #endif
629 #ifdef IFT_L3IPVLAN
630 			case IFT_L3IPVLAN: /* FALLTHROUGH */
631 #endif
632 			case IFT_ETHER:
633 				ifp->hwtype = ARPHRD_ETHER;
634 				break;
635 #ifdef IFT_IEEE1394
636 			case IFT_IEEE1394:
637 				ifp->hwtype = ARPHRD_IEEE1394;
638 				break;
639 #endif
640 #ifdef IFT_INFINIBAND
641 			case IFT_INFINIBAND:
642 				ifp->hwtype = ARPHRD_INFINIBAND;
643 				break;
644 #endif
645 			default:
646 				/* Don't allow unless explicit */
647 				if (active) {
648 					if (if_noconf)
649 						active = IF_INACTIVE;
650 					i = active ? LOG_WARNING : LOG_DEBUG;
651 					logmessage(i, "%s: unsupported"
652 					    " interface type 0x%.2x",
653 					    ifp->name, sdl->sdl_type);
654 				}
655 				/* Pretend it's ethernet */
656 				ifp->hwtype = ARPHRD_ETHER;
657 				break;
658 			}
659 			ifp->hwlen = sdl->sdl_alen;
660 			memcpy(ifp->hwaddr, CLLADDR(sdl), ifp->hwlen);
661 #elif defined(AF_PACKET)
662 			sll = (const void *)ifa->ifa_addr;
663 			ifp->index = (unsigned int)sll->sll_ifindex;
664 			ifp->hwtype = sll->sll_hatype;
665 			ifp->hwlen = sll->sll_halen;
666 			if (ifp->hwlen != 0)
667 				memcpy(ifp->hwaddr, sll->sll_addr, ifp->hwlen);
668 			active = if_check_arphrd(ifp, active, if_noconf);
669 #endif
670 		}
671 #ifdef __linux__
672 		else {
673 			struct ifreq ifr = { .ifr_flags = 0 };
674 
675 			/* This is a huge bug in getifaddrs(3) as there
676 			 * is no reason why this can't be returned in
677 			 * ifa_addr. */
678 			strlcpy(ifr.ifr_name, ifa->ifa_name,
679 			    sizeof(ifr.ifr_name));
680 			if (ioctl(ctx->pf_inet_fd, SIOCGIFHWADDR, &ifr) == -1)
681 				logerr("%s: SIOCGIFHWADDR", ifa->ifa_name);
682 			ifp->hwtype = ifr.ifr_hwaddr.sa_family;
683 			if (ioctl(ctx->pf_inet_fd, SIOCGIFINDEX, &ifr) == -1)
684 				logerr("%s: SIOCGIFINDEX", ifa->ifa_name);
685 			ifp->index = (unsigned int)ifr.ifr_ifindex;
686 			if_check_arphrd(ifp, active, if_noconf);
687 		}
688 #endif
689 
690 		if (!(ctx->options & (DHCPCD_DUMPLEASE | DHCPCD_TEST))) {
691 			/* Handle any platform init for the interface */
692 			if (active != IF_INACTIVE && if_init(ifp) == -1) {
693 				logerr("%s: if_init", ifp->name);
694 				if_free(ifp);
695 				continue;
696 			}
697 		}
698 
699 		ifp->vlanid = if_vlanid(ifp);
700 
701 #ifdef SIOCGIFPRIORITY
702 		/* Respect the interface priority */
703 		memset(&ifr, 0, sizeof(ifr));
704 		strlcpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
705 		if (pioctl(ctx, SIOCGIFPRIORITY, &ifr, sizeof(ifr)) == 0)
706 			ifp->metric = (unsigned int)ifr.ifr_metric;
707 		if_getssid(ifp);
708 #else
709 		/* Leave a low portion for user config */
710 		ifp->metric = RTMETRIC_BASE + ifp->index;
711 		if (if_getssid(ifp) != -1) {
712 			ifp->wireless = true;
713 			ifp->metric += RTMETRIC_WIRELESS;
714 		}
715 #endif
716 
717 		ifp->active = active;
718 		ifp->carrier = if_carrier(ifp, ifa->ifa_data);
719 		TAILQ_INSERT_TAIL(ifs, ifp, next);
720 	}
721 
722 	return ifs;
723 }
724 
725 /*
726  * eth0.100:2 OR eth0i100:2 (seems to be NetBSD xvif(4) only)
727  *
728  * drvname == eth
729  * devname == eth0.100 OR eth0i100
730  * ppa = 0
731  * lun = 2
732  */
733 int
734 if_nametospec(const char *ifname, struct if_spec *spec)
735 {
736 	char *ep, *pp;
737 	int e;
738 
739 	if (ifname == NULL || *ifname == '\0' ||
740 	    strlcpy(spec->ifname, ifname, sizeof(spec->ifname)) >=
741 	    sizeof(spec->ifname) ||
742 	    strlcpy(spec->drvname, ifname, sizeof(spec->drvname)) >=
743 	    sizeof(spec->drvname))
744 	{
745 		errno = EINVAL;
746 		return -1;
747 	}
748 
749 	/* :N is an alias */
750 	ep = strchr(spec->drvname, ':');
751 	if (ep) {
752 		spec->lun = (int)strtoi(ep + 1, NULL, 10, 0, INT_MAX, &e);
753 		if (e != 0) {
754 			errno = e;
755 			return -1;
756 		}
757 		*ep = '\0';
758 #ifdef __sun
759 		ep--;
760 #endif
761 	} else {
762 		spec->lun = -1;
763 #ifdef __sun
764 		ep = spec->drvname + strlen(spec->drvname) - 1;
765 #endif
766 	}
767 
768 	strlcpy(spec->devname, spec->drvname, sizeof(spec->devname));
769 #ifdef __sun
770 	/* Solaris has numbers in the driver name, such as e1000g */
771 	while (ep > spec->drvname && isdigit((int)*ep))
772 		ep--;
773 	if (*ep++ == ':') {
774 		errno = EINVAL;
775 		return -1;
776 	}
777 #else
778 	/* BSD and Linux no not have numbers in the driver name */
779 	for (ep = spec->drvname; *ep != '\0' && !isdigit((int)*ep); ep++) {
780 		if (*ep == ':') {
781 			errno = EINVAL;
782 			return -1;
783 		}
784 	}
785 #endif
786 	spec->ppa = (int)strtoi(ep, &pp, 10, 0, INT_MAX, &e);
787 	*ep = '\0';
788 
789 #ifndef __sun
790 	/*
791 	 * . is used for VLAN style names
792 	 * i is used on NetBSD for xvif interfaces
793 	 */
794 	if (pp != NULL && (*pp == '.' || *pp == 'i')) {
795 		spec->vlid = (int)strtoi(pp + 1, NULL, 10, 0, INT_MAX, &e);
796 		if (e)
797 			spec->vlid = -1;
798 	} else
799 #endif
800 		spec->vlid = -1;
801 
802 	return 0;
803 }
804 
805 static struct interface *
806 if_findindexname(struct if_head *ifaces, unsigned int idx, const char *name)
807 {
808 
809 	if (ifaces != NULL) {
810 		struct if_spec spec;
811 		struct interface *ifp;
812 
813 		if (name && if_nametospec(name, &spec) == -1)
814 			return NULL;
815 
816 		TAILQ_FOREACH(ifp, ifaces, next) {
817 			if ((name && strcmp(ifp->name, spec.devname) == 0) ||
818 			    (!name && ifp->index == idx))
819 				return ifp;
820 		}
821 	}
822 
823 	errno = ENXIO;
824 	return NULL;
825 }
826 
827 struct interface *
828 if_find(struct if_head *ifaces, const char *name)
829 {
830 
831 	return if_findindexname(ifaces, 0, name);
832 }
833 
834 struct interface *
835 if_findindex(struct if_head *ifaces, unsigned int idx)
836 {
837 
838 	return if_findindexname(ifaces, idx, NULL);
839 }
840 
841 struct interface *
842 if_loopback(struct dhcpcd_ctx *ctx)
843 {
844 	struct interface *ifp;
845 
846 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
847 		if (ifp->flags & IFF_LOOPBACK)
848 			return ifp;
849 	}
850 	return NULL;
851 }
852 
853 int
854 if_domtu(const struct interface *ifp, short int mtu)
855 {
856 	int r;
857 	struct ifreq ifr;
858 
859 #ifdef __sun
860 	if (mtu == 0)
861 		return if_mtu_os(ifp);
862 #endif
863 
864 	memset(&ifr, 0, sizeof(ifr));
865 	strlcpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
866 	ifr.ifr_mtu = mtu;
867 	if (mtu != 0)
868 		r = if_ioctl(ifp->ctx, SIOCSIFMTU, &ifr, sizeof(ifr));
869 	else
870 		r = pioctl(ifp->ctx, SIOCGIFMTU, &ifr, sizeof(ifr));
871 
872 	if (r == -1)
873 		return -1;
874 	return ifr.ifr_mtu;
875 }
876 
877 #ifdef ALIAS_ADDR
878 int
879 if_makealias(char *alias, size_t alias_len, const char *ifname, int lun)
880 {
881 
882 	if (lun == 0)
883 		return strlcpy(alias, ifname, alias_len);
884 	return snprintf(alias, alias_len, "%s:%u", ifname, lun);
885 }
886 #endif
887 
888 struct interface *
889 if_findifpfromcmsg(struct dhcpcd_ctx *ctx, struct msghdr *msg, int *hoplimit)
890 {
891 	struct cmsghdr *cm;
892 	unsigned int ifindex = 0;
893 	struct interface *ifp;
894 #ifdef INET
895 #ifdef IP_RECVIF
896 	struct sockaddr_dl sdl;
897 #else
898 	struct in_pktinfo ipi;
899 #endif
900 #endif
901 #ifdef INET6
902 	struct in6_pktinfo ipi6;
903 #else
904 	UNUSED(hoplimit);
905 #endif
906 
907 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(msg);
908 	     cm;
909 	     cm = (struct cmsghdr *)CMSG_NXTHDR(msg, cm))
910 	{
911 #ifdef INET
912 		if (cm->cmsg_level == IPPROTO_IP) {
913 			switch(cm->cmsg_type) {
914 #ifdef IP_RECVIF
915 			case IP_RECVIF:
916 				if (cm->cmsg_len <
917 				    offsetof(struct sockaddr_dl, sdl_index) +
918 				    sizeof(sdl.sdl_index))
919 					continue;
920 				memcpy(&sdl, CMSG_DATA(cm),
921 				    MIN(sizeof(sdl), cm->cmsg_len));
922 				ifindex = sdl.sdl_index;
923 				break;
924 #else
925 			case IP_PKTINFO:
926 				if (cm->cmsg_len != CMSG_LEN(sizeof(ipi)))
927 					continue;
928 				memcpy(&ipi, CMSG_DATA(cm), sizeof(ipi));
929 				ifindex = (unsigned int)ipi.ipi_ifindex;
930 				break;
931 #endif
932 			}
933 		}
934 #endif
935 #ifdef INET6
936 		if (cm->cmsg_level == IPPROTO_IPV6) {
937 			switch(cm->cmsg_type) {
938 			case IPV6_PKTINFO:
939 				if (cm->cmsg_len != CMSG_LEN(sizeof(ipi6)))
940 					continue;
941 				memcpy(&ipi6, CMSG_DATA(cm), sizeof(ipi6));
942 				ifindex = (unsigned int)ipi6.ipi6_ifindex;
943 				break;
944 			case IPV6_HOPLIMIT:
945 				if (cm->cmsg_len != CMSG_LEN(sizeof(int)))
946 					continue;
947 				if (hoplimit == NULL)
948 					break;
949 				memcpy(hoplimit, CMSG_DATA(cm), sizeof(int));
950 				break;
951 			}
952 		}
953 #endif
954 	}
955 
956 	/* Find the receiving interface */
957 	TAILQ_FOREACH(ifp, ctx->ifaces, next) {
958 		if (ifp->index == ifindex)
959 			break;
960 	}
961 	if (ifp == NULL)
962 		errno = ESRCH;
963 	return ifp;
964 }
965 
966 int
967 xsocket(int domain, int type, int protocol)
968 {
969 	int s;
970 #if !defined(HAVE_SOCK_CLOEXEC) || !defined(HAVE_SOCK_NONBLOCK)
971 	int xflags, xtype = type;
972 #endif
973 
974 #ifndef HAVE_SOCK_CLOEXEC
975 	if (xtype & SOCK_CLOEXEC)
976 		type &= ~SOCK_CLOEXEC;
977 #endif
978 #ifndef HAVE_SOCK_NONBLOCK
979 	if (xtype & SOCK_NONBLOCK)
980 		type &= ~SOCK_NONBLOCK;
981 #endif
982 
983 	if ((s = socket(domain, type, protocol)) == -1)
984 		return -1;
985 
986 #ifndef HAVE_SOCK_CLOEXEC
987 	if ((xtype & SOCK_CLOEXEC) && ((xflags = fcntl(s, F_GETFD)) == -1 ||
988 	    fcntl(s, F_SETFD, xflags | FD_CLOEXEC) == -1))
989 		goto out;
990 #endif
991 #ifndef HAVE_SOCK_NONBLOCK
992 	if ((xtype & SOCK_NONBLOCK) && ((xflags = fcntl(s, F_GETFL)) == -1 ||
993 	    fcntl(s, F_SETFL, xflags | O_NONBLOCK) == -1))
994 		goto out;
995 #endif
996 
997 	return s;
998 
999 #if !defined(HAVE_SOCK_CLOEXEC) || !defined(HAVE_SOCK_NONBLOCK)
1000 out:
1001 	close(s);
1002 	return -1;
1003 #endif
1004 }
1005 
1006 int
1007 xsocketpair(int domain, int type, int protocol, int fd[2])
1008 {
1009 	int s;
1010 #if !defined(HAVE_SOCK_CLOEXEC) || !defined(HAVE_SOCK_NONBLOCK)
1011 	int xflags, xtype = type;
1012 #endif
1013 
1014 #ifndef HAVE_SOCK_CLOEXEC
1015 	if (xtype & SOCK_CLOEXEC)
1016 		type &= ~SOCK_CLOEXEC;
1017 #endif
1018 #ifndef HAVE_SOCK_NONBLOCK
1019 	if (xtype & SOCK_NONBLOCK)
1020 		type &= ~SOCK_NONBLOCK;
1021 #endif
1022 
1023 	if ((s = socketpair(domain, type, protocol, fd)) == -1)
1024 		return -1;
1025 
1026 #ifndef HAVE_SOCK_CLOEXEC
1027 	if ((xtype & SOCK_CLOEXEC) && ((xflags = fcntl(fd[0], F_GETFD)) == -1 ||
1028 	    fcntl(fd[0], F_SETFD, xflags | FD_CLOEXEC) == -1))
1029 		goto out;
1030 	if ((xtype & SOCK_CLOEXEC) && ((xflags = fcntl(fd[1], F_GETFD)) == -1 ||
1031 	    fcntl(fd[1], F_SETFD, xflags | FD_CLOEXEC) == -1))
1032 		goto out;
1033 #endif
1034 #ifndef HAVE_SOCK_NONBLOCK
1035 	if ((xtype & SOCK_NONBLOCK) && ((xflags = fcntl(fd[0], F_GETFL)) == -1 ||
1036 	    fcntl(fd[0], F_SETFL, xflags | O_NONBLOCK) == -1))
1037 		goto out;
1038 	if ((xtype & SOCK_NONBLOCK) && ((xflags = fcntl(fd[1], F_GETFL)) == -1 ||
1039 	    fcntl(fd[1], F_SETFL, xflags | O_NONBLOCK) == -1))
1040 		goto out;
1041 #endif
1042 
1043 	return s;
1044 
1045 #if !defined(HAVE_SOCK_CLOEXEC) || !defined(HAVE_SOCK_NONBLOCK)
1046 out:
1047 	close(fd[0]);
1048 	close(fd[1]);
1049 	return -1;
1050 #endif
1051 }
1052