xref: /freebsd/contrib/wpa/src/ap/vlan_full.c (revision 148a8da8)
1 /*
2  * hostapd / VLAN initialization - full dynamic VLAN
3  * Copyright 2003, Instant802 Networks, Inc.
4  * Copyright 2005-2006, Devicescape Software, Inc.
5  * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
6  *
7  * This software may be distributed under the terms of the BSD license.
8  * See README for more details.
9  */
10 
11 #include "utils/includes.h"
12 #include <net/if.h>
13 /* Avoid conflicts due to NetBSD net/if.h if_type define with driver.h */
14 #undef if_type
15 #include <sys/ioctl.h>
16 
17 #include "utils/common.h"
18 #include "drivers/priv_netlink.h"
19 #include "common/linux_bridge.h"
20 #include "common/linux_vlan.h"
21 #include "utils/eloop.h"
22 #include "hostapd.h"
23 #include "ap_config.h"
24 #include "ap_drv_ops.h"
25 #include "wpa_auth.h"
26 #include "vlan_init.h"
27 #include "vlan_util.h"
28 
29 
30 struct full_dynamic_vlan {
31 	int s; /* socket on which to listen for new/removed interfaces. */
32 };
33 
34 #define DVLAN_CLEAN_BR         0x1
35 #define DVLAN_CLEAN_VLAN       0x2
36 #define DVLAN_CLEAN_VLAN_PORT  0x4
37 
38 struct dynamic_iface {
39 	char ifname[IFNAMSIZ + 1];
40 	int usage;
41 	int clean;
42 	struct dynamic_iface *next;
43 };
44 
45 
46 /* Increment ref counter for ifname and add clean flag.
47  * If not in list, add it only if some flags are given.
48  */
49 static void dyn_iface_get(struct hostapd_data *hapd, const char *ifname,
50 			  int clean)
51 {
52 	struct dynamic_iface *next, **dynamic_ifaces;
53 	struct hapd_interfaces *interfaces;
54 
55 	interfaces = hapd->iface->interfaces;
56 	dynamic_ifaces = &interfaces->vlan_priv;
57 
58 	for (next = *dynamic_ifaces; next; next = next->next) {
59 		if (os_strcmp(ifname, next->ifname) == 0)
60 			break;
61 	}
62 
63 	if (next) {
64 		next->usage++;
65 		next->clean |= clean;
66 		return;
67 	}
68 
69 	if (!clean)
70 		return;
71 
72 	next = os_zalloc(sizeof(*next));
73 	if (!next)
74 		return;
75 	os_strlcpy(next->ifname, ifname, sizeof(next->ifname));
76 	next->usage = 1;
77 	next->clean = clean;
78 	next->next = *dynamic_ifaces;
79 	*dynamic_ifaces = next;
80 }
81 
82 
83 /* Decrement reference counter for given ifname.
84  * Return clean flag iff reference counter was decreased to zero, else zero
85  */
86 static int dyn_iface_put(struct hostapd_data *hapd, const char *ifname)
87 {
88 	struct dynamic_iface *next, *prev = NULL, **dynamic_ifaces;
89 	struct hapd_interfaces *interfaces;
90 	int clean;
91 
92 	interfaces = hapd->iface->interfaces;
93 	dynamic_ifaces = &interfaces->vlan_priv;
94 
95 	for (next = *dynamic_ifaces; next; next = next->next) {
96 		if (os_strcmp(ifname, next->ifname) == 0)
97 			break;
98 		prev = next;
99 	}
100 
101 	if (!next)
102 		return 0;
103 
104 	next->usage--;
105 	if (next->usage)
106 		return 0;
107 
108 	if (prev)
109 		prev->next = next->next;
110 	else
111 		*dynamic_ifaces = next->next;
112 	clean = next->clean;
113 	os_free(next);
114 
115 	return clean;
116 }
117 
118 
119 static int ifconfig_down(const char *if_name)
120 {
121 	wpa_printf(MSG_DEBUG, "VLAN: Set interface %s down", if_name);
122 	return ifconfig_helper(if_name, 0);
123 }
124 
125 
126 /* This value should be 256 ONLY. If it is something else, then hostapd
127  * might crash!, as this value has been hard-coded in 2.4.x kernel
128  * bridging code.
129  */
130 #define MAX_BR_PORTS      		256
131 
132 static int br_delif(const char *br_name, const char *if_name)
133 {
134 	int fd;
135 	struct ifreq ifr;
136 	unsigned long args[2];
137 	int if_index;
138 
139 	wpa_printf(MSG_DEBUG, "VLAN: br_delif(%s, %s)", br_name, if_name);
140 	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
141 		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
142 			   "failed: %s", __func__, strerror(errno));
143 		return -1;
144 	}
145 
146 	if_index = if_nametoindex(if_name);
147 
148 	if (if_index == 0) {
149 		wpa_printf(MSG_ERROR, "VLAN: %s: Failure determining "
150 			   "interface index for '%s'",
151 			   __func__, if_name);
152 		close(fd);
153 		return -1;
154 	}
155 
156 	args[0] = BRCTL_DEL_IF;
157 	args[1] = if_index;
158 
159 	os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
160 	ifr.ifr_data = (void *) args;
161 
162 	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0 && errno != EINVAL) {
163 		/* No error if interface already removed. */
164 		wpa_printf(MSG_ERROR, "VLAN: %s: ioctl[SIOCDEVPRIVATE,"
165 			   "BRCTL_DEL_IF] failed for br_name=%s if_name=%s: "
166 			   "%s", __func__, br_name, if_name, strerror(errno));
167 		close(fd);
168 		return -1;
169 	}
170 
171 	close(fd);
172 	return 0;
173 }
174 
175 
176 /*
177 	Add interface 'if_name' to the bridge 'br_name'
178 
179 	returns -1 on error
180 	returns 1 if the interface is already part of the bridge
181 	returns 0 otherwise
182 */
183 static int br_addif(const char *br_name, const char *if_name)
184 {
185 	int fd;
186 	struct ifreq ifr;
187 	unsigned long args[2];
188 	int if_index;
189 
190 	wpa_printf(MSG_DEBUG, "VLAN: br_addif(%s, %s)", br_name, if_name);
191 	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
192 		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
193 			   "failed: %s", __func__, strerror(errno));
194 		return -1;
195 	}
196 
197 	if_index = if_nametoindex(if_name);
198 
199 	if (if_index == 0) {
200 		wpa_printf(MSG_ERROR, "VLAN: %s: Failure determining "
201 			   "interface index for '%s'",
202 			   __func__, if_name);
203 		close(fd);
204 		return -1;
205 	}
206 
207 	args[0] = BRCTL_ADD_IF;
208 	args[1] = if_index;
209 
210 	os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
211 	ifr.ifr_data = (void *) args;
212 
213 	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
214 		if (errno == EBUSY) {
215 			/* The interface is already added. */
216 			close(fd);
217 			return 1;
218 		}
219 
220 		wpa_printf(MSG_ERROR, "VLAN: %s: ioctl[SIOCDEVPRIVATE,"
221 			   "BRCTL_ADD_IF] failed for br_name=%s if_name=%s: "
222 			   "%s", __func__, br_name, if_name, strerror(errno));
223 		close(fd);
224 		return -1;
225 	}
226 
227 	close(fd);
228 	return 0;
229 }
230 
231 
232 static int br_delbr(const char *br_name)
233 {
234 	int fd;
235 	unsigned long arg[2];
236 
237 	wpa_printf(MSG_DEBUG, "VLAN: br_delbr(%s)", br_name);
238 	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
239 		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
240 			   "failed: %s", __func__, strerror(errno));
241 		return -1;
242 	}
243 
244 	arg[0] = BRCTL_DEL_BRIDGE;
245 	arg[1] = (unsigned long) br_name;
246 
247 	if (ioctl(fd, SIOCGIFBR, arg) < 0 && errno != ENXIO) {
248 		/* No error if bridge already removed. */
249 		wpa_printf(MSG_ERROR, "VLAN: %s: BRCTL_DEL_BRIDGE failed for "
250 			   "%s: %s", __func__, br_name, strerror(errno));
251 		close(fd);
252 		return -1;
253 	}
254 
255 	close(fd);
256 	return 0;
257 }
258 
259 
260 /*
261 	Add a bridge with the name 'br_name'.
262 
263 	returns -1 on error
264 	returns 1 if the bridge already exists
265 	returns 0 otherwise
266 */
267 static int br_addbr(const char *br_name)
268 {
269 	int fd;
270 	unsigned long arg[4];
271 	struct ifreq ifr;
272 
273 	wpa_printf(MSG_DEBUG, "VLAN: br_addbr(%s)", br_name);
274 	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
275 		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
276 			   "failed: %s", __func__, strerror(errno));
277 		return -1;
278 	}
279 
280 	arg[0] = BRCTL_ADD_BRIDGE;
281 	arg[1] = (unsigned long) br_name;
282 
283 	if (ioctl(fd, SIOCGIFBR, arg) < 0) {
284  		if (errno == EEXIST) {
285 			/* The bridge is already added. */
286 			close(fd);
287 			return 1;
288 		} else {
289 			wpa_printf(MSG_ERROR, "VLAN: %s: BRCTL_ADD_BRIDGE "
290 				   "failed for %s: %s",
291 				   __func__, br_name, strerror(errno));
292 			close(fd);
293 			return -1;
294 		}
295 	}
296 
297 	/* Decrease forwarding delay to avoid EAPOL timeouts. */
298 	os_memset(&ifr, 0, sizeof(ifr));
299 	os_strlcpy(ifr.ifr_name, br_name, IFNAMSIZ);
300 	arg[0] = BRCTL_SET_BRIDGE_FORWARD_DELAY;
301 	arg[1] = 1;
302 	arg[2] = 0;
303 	arg[3] = 0;
304 	ifr.ifr_data = (char *) &arg;
305 	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
306 		wpa_printf(MSG_ERROR, "VLAN: %s: "
307 			   "BRCTL_SET_BRIDGE_FORWARD_DELAY (1 sec) failed for "
308 			   "%s: %s", __func__, br_name, strerror(errno));
309 		/* Continue anyway */
310 	}
311 
312 	close(fd);
313 	return 0;
314 }
315 
316 
317 static int br_getnumports(const char *br_name)
318 {
319 	int fd;
320 	int i;
321 	int port_cnt = 0;
322 	unsigned long arg[4];
323 	int ifindices[MAX_BR_PORTS];
324 	struct ifreq ifr;
325 
326 	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
327 		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
328 			   "failed: %s", __func__, strerror(errno));
329 		return -1;
330 	}
331 
332 	arg[0] = BRCTL_GET_PORT_LIST;
333 	arg[1] = (unsigned long) ifindices;
334 	arg[2] = MAX_BR_PORTS;
335 	arg[3] = 0;
336 
337 	os_memset(ifindices, 0, sizeof(ifindices));
338 	os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
339 	ifr.ifr_data = (void *) arg;
340 
341 	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
342 		wpa_printf(MSG_ERROR, "VLAN: %s: BRCTL_GET_PORT_LIST "
343 			   "failed for %s: %s",
344 			   __func__, br_name, strerror(errno));
345 		close(fd);
346 		return -1;
347 	}
348 
349 	for (i = 1; i < MAX_BR_PORTS; i++) {
350 		if (ifindices[i] > 0) {
351 			port_cnt++;
352 		}
353 	}
354 
355 	close(fd);
356 	return port_cnt;
357 }
358 
359 
360 static void vlan_newlink_tagged(int vlan_naming, const char *tagged_interface,
361 				const char *br_name, int vid,
362 				struct hostapd_data *hapd)
363 {
364 	char vlan_ifname[IFNAMSIZ];
365 	int clean;
366 
367 	if (vlan_naming == DYNAMIC_VLAN_NAMING_WITH_DEVICE)
368 		os_snprintf(vlan_ifname, sizeof(vlan_ifname), "%s.%d",
369 			    tagged_interface, vid);
370 	else
371 		os_snprintf(vlan_ifname, sizeof(vlan_ifname), "vlan%d", vid);
372 
373 	clean = 0;
374 	ifconfig_up(tagged_interface);
375 	if (!vlan_add(tagged_interface, vid, vlan_ifname))
376 		clean |= DVLAN_CLEAN_VLAN;
377 
378 	if (!br_addif(br_name, vlan_ifname))
379 		clean |= DVLAN_CLEAN_VLAN_PORT;
380 
381 	dyn_iface_get(hapd, vlan_ifname, clean);
382 
383 	ifconfig_up(vlan_ifname);
384 }
385 
386 
387 static void vlan_bridge_name(char *br_name, struct hostapd_data *hapd, int vid)
388 {
389 	char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;
390 
391 	if (hapd->conf->vlan_bridge[0]) {
392 		os_snprintf(br_name, IFNAMSIZ, "%s%d",
393 			    hapd->conf->vlan_bridge, vid);
394 	} else if (tagged_interface) {
395 		os_snprintf(br_name, IFNAMSIZ, "br%s.%d",
396 			    tagged_interface, vid);
397 	} else {
398 		os_snprintf(br_name, IFNAMSIZ, "brvlan%d", vid);
399 	}
400 }
401 
402 
403 static void vlan_get_bridge(const char *br_name, struct hostapd_data *hapd,
404 			    int vid)
405 {
406 	char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;
407 	int vlan_naming = hapd->conf->ssid.vlan_naming;
408 
409 	dyn_iface_get(hapd, br_name, br_addbr(br_name) ? 0 : DVLAN_CLEAN_BR);
410 
411 	ifconfig_up(br_name);
412 
413 	if (tagged_interface)
414 		vlan_newlink_tagged(vlan_naming, tagged_interface, br_name,
415 				    vid, hapd);
416 }
417 
418 
419 void vlan_newlink(const char *ifname, struct hostapd_data *hapd)
420 {
421 	char br_name[IFNAMSIZ];
422 	struct hostapd_vlan *vlan;
423 	int untagged, *tagged, i, notempty;
424 
425 	wpa_printf(MSG_DEBUG, "VLAN: vlan_newlink(%s)", ifname);
426 
427 	for (vlan = hapd->conf->vlan; vlan; vlan = vlan->next) {
428 		if (vlan->configured ||
429 		    os_strcmp(ifname, vlan->ifname) != 0)
430 			continue;
431 		break;
432 	}
433 	if (!vlan)
434 		return;
435 
436 	vlan->configured = 1;
437 
438 	notempty = vlan->vlan_desc.notempty;
439 	untagged = vlan->vlan_desc.untagged;
440 	tagged = vlan->vlan_desc.tagged;
441 
442 	if (!notempty) {
443 		/* Non-VLAN STA */
444 		if (hapd->conf->bridge[0] &&
445 		    !br_addif(hapd->conf->bridge, ifname))
446 			vlan->clean |= DVLAN_CLEAN_WLAN_PORT;
447 	} else if (untagged > 0 && untagged <= MAX_VLAN_ID) {
448 		vlan_bridge_name(br_name, hapd, untagged);
449 
450 		vlan_get_bridge(br_name, hapd, untagged);
451 
452 		if (!br_addif(br_name, ifname))
453 			vlan->clean |= DVLAN_CLEAN_WLAN_PORT;
454 	}
455 
456 	for (i = 0; i < MAX_NUM_TAGGED_VLAN && tagged[i]; i++) {
457 		if (tagged[i] == untagged ||
458 		    tagged[i] <= 0 || tagged[i] > MAX_VLAN_ID ||
459 		    (i > 0 && tagged[i] == tagged[i - 1]))
460 			continue;
461 		vlan_bridge_name(br_name, hapd, tagged[i]);
462 		vlan_get_bridge(br_name, hapd, tagged[i]);
463 		vlan_newlink_tagged(DYNAMIC_VLAN_NAMING_WITH_DEVICE,
464 				    ifname, br_name, tagged[i], hapd);
465 	}
466 
467 	ifconfig_up(ifname);
468 }
469 
470 
471 static void vlan_dellink_tagged(int vlan_naming, const char *tagged_interface,
472 				const char *br_name, int vid,
473 				struct hostapd_data *hapd)
474 {
475 	char vlan_ifname[IFNAMSIZ];
476 	int clean;
477 
478 	if (vlan_naming == DYNAMIC_VLAN_NAMING_WITH_DEVICE)
479 		os_snprintf(vlan_ifname, sizeof(vlan_ifname), "%s.%d",
480 			    tagged_interface, vid);
481 	else
482 		os_snprintf(vlan_ifname, sizeof(vlan_ifname), "vlan%d", vid);
483 
484 	clean = dyn_iface_put(hapd, vlan_ifname);
485 
486 	if (clean & DVLAN_CLEAN_VLAN_PORT)
487 		br_delif(br_name, vlan_ifname);
488 
489 	if (clean & DVLAN_CLEAN_VLAN) {
490 		ifconfig_down(vlan_ifname);
491 		vlan_rem(vlan_ifname);
492 	}
493 }
494 
495 
496 static void vlan_put_bridge(const char *br_name, struct hostapd_data *hapd,
497 			    int vid)
498 {
499 	int clean;
500 	char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;
501 	int vlan_naming = hapd->conf->ssid.vlan_naming;
502 
503 	if (tagged_interface)
504 		vlan_dellink_tagged(vlan_naming, tagged_interface, br_name,
505 				    vid, hapd);
506 
507 	clean = dyn_iface_put(hapd, br_name);
508 	if ((clean & DVLAN_CLEAN_BR) && br_getnumports(br_name) == 0) {
509 		ifconfig_down(br_name);
510 		br_delbr(br_name);
511 	}
512 }
513 
514 
515 void vlan_dellink(const char *ifname, struct hostapd_data *hapd)
516 {
517 	struct hostapd_vlan *first, *prev, *vlan = hapd->conf->vlan;
518 
519 	wpa_printf(MSG_DEBUG, "VLAN: vlan_dellink(%s)", ifname);
520 
521 	first = prev = vlan;
522 
523 	while (vlan) {
524 		if (os_strcmp(ifname, vlan->ifname) != 0) {
525 			prev = vlan;
526 			vlan = vlan->next;
527 			continue;
528 		}
529 		break;
530 	}
531 	if (!vlan)
532 		return;
533 
534 	if (vlan->configured) {
535 		int notempty = vlan->vlan_desc.notempty;
536 		int untagged = vlan->vlan_desc.untagged;
537 		int *tagged = vlan->vlan_desc.tagged;
538 		char br_name[IFNAMSIZ];
539 		int i;
540 
541 		for (i = 0; i < MAX_NUM_TAGGED_VLAN && tagged[i]; i++) {
542 			if (tagged[i] == untagged ||
543 			    tagged[i] <= 0 || tagged[i] > MAX_VLAN_ID ||
544 			    (i > 0 && tagged[i] == tagged[i - 1]))
545 				continue;
546 			vlan_bridge_name(br_name, hapd, tagged[i]);
547 			vlan_dellink_tagged(DYNAMIC_VLAN_NAMING_WITH_DEVICE,
548 					    ifname, br_name, tagged[i], hapd);
549 			vlan_put_bridge(br_name, hapd, tagged[i]);
550 		}
551 
552 		if (!notempty) {
553 			/* Non-VLAN STA */
554 			if (hapd->conf->bridge[0] &&
555 			    (vlan->clean & DVLAN_CLEAN_WLAN_PORT))
556 				br_delif(hapd->conf->bridge, ifname);
557 		} else if (untagged > 0 && untagged <= MAX_VLAN_ID) {
558 			vlan_bridge_name(br_name, hapd, untagged);
559 
560 			if (vlan->clean & DVLAN_CLEAN_WLAN_PORT)
561 				br_delif(br_name, vlan->ifname);
562 
563 			vlan_put_bridge(br_name, hapd, untagged);
564 		}
565 	}
566 
567 	/*
568 	 * Ensure this VLAN interface is actually removed even if
569 	 * NEWLINK message is only received later.
570 	 */
571 	if (if_nametoindex(vlan->ifname) && vlan_if_remove(hapd, vlan))
572 		wpa_printf(MSG_ERROR,
573 			   "VLAN: Could not remove VLAN iface: %s: %s",
574 			   vlan->ifname, strerror(errno));
575 
576 	if (vlan == first)
577 		hapd->conf->vlan = vlan->next;
578 	else
579 		prev->next = vlan->next;
580 
581 	os_free(vlan);
582 }
583 
584 
585 static void
586 vlan_read_ifnames(struct nlmsghdr *h, size_t len, int del,
587 		  struct hostapd_data *hapd)
588 {
589 	struct ifinfomsg *ifi;
590 	int attrlen, nlmsg_len, rta_len;
591 	struct rtattr *attr;
592 	char ifname[IFNAMSIZ + 1];
593 
594 	if (len < sizeof(*ifi))
595 		return;
596 
597 	ifi = NLMSG_DATA(h);
598 
599 	nlmsg_len = NLMSG_ALIGN(sizeof(struct ifinfomsg));
600 
601 	attrlen = h->nlmsg_len - nlmsg_len;
602 	if (attrlen < 0)
603 		return;
604 
605 	attr = (struct rtattr *) (((char *) ifi) + nlmsg_len);
606 
607 	os_memset(ifname, 0, sizeof(ifname));
608 	rta_len = RTA_ALIGN(sizeof(struct rtattr));
609 	while (RTA_OK(attr, attrlen)) {
610 		if (attr->rta_type == IFLA_IFNAME) {
611 			int n = attr->rta_len - rta_len;
612 			if (n < 0)
613 				break;
614 
615 			if ((size_t) n >= sizeof(ifname))
616 				n = sizeof(ifname) - 1;
617 			os_memcpy(ifname, ((char *) attr) + rta_len, n);
618 
619 		}
620 
621 		attr = RTA_NEXT(attr, attrlen);
622 	}
623 
624 	if (!ifname[0])
625 		return;
626 	if (del && if_nametoindex(ifname)) {
627 		 /* interface still exists, race condition ->
628 		  * iface has just been recreated */
629 		return;
630 	}
631 
632 	wpa_printf(MSG_DEBUG,
633 		   "VLAN: RTM_%sLINK: ifi_index=%d ifname=%s ifi_family=%d ifi_flags=0x%x (%s%s%s%s)",
634 		   del ? "DEL" : "NEW",
635 		   ifi->ifi_index, ifname, ifi->ifi_family, ifi->ifi_flags,
636 		   (ifi->ifi_flags & IFF_UP) ? "[UP]" : "",
637 		   (ifi->ifi_flags & IFF_RUNNING) ? "[RUNNING]" : "",
638 		   (ifi->ifi_flags & IFF_LOWER_UP) ? "[LOWER_UP]" : "",
639 		   (ifi->ifi_flags & IFF_DORMANT) ? "[DORMANT]" : "");
640 
641 	if (del)
642 		vlan_dellink(ifname, hapd);
643 	else
644 		vlan_newlink(ifname, hapd);
645 }
646 
647 
648 static void vlan_event_receive(int sock, void *eloop_ctx, void *sock_ctx)
649 {
650 	char buf[8192];
651 	int left;
652 	struct sockaddr_nl from;
653 	socklen_t fromlen;
654 	struct nlmsghdr *h;
655 	struct hostapd_data *hapd = eloop_ctx;
656 
657 	fromlen = sizeof(from);
658 	left = recvfrom(sock, buf, sizeof(buf), MSG_DONTWAIT,
659 			(struct sockaddr *) &from, &fromlen);
660 	if (left < 0) {
661 		if (errno != EINTR && errno != EAGAIN)
662 			wpa_printf(MSG_ERROR, "VLAN: %s: recvfrom failed: %s",
663 				   __func__, strerror(errno));
664 		return;
665 	}
666 
667 	h = (struct nlmsghdr *) buf;
668 	while (NLMSG_OK(h, left)) {
669 		int len, plen;
670 
671 		len = h->nlmsg_len;
672 		plen = len - sizeof(*h);
673 		if (len > left || plen < 0) {
674 			wpa_printf(MSG_DEBUG, "VLAN: Malformed netlink "
675 				   "message: len=%d left=%d plen=%d",
676 				   len, left, plen);
677 			break;
678 		}
679 
680 		switch (h->nlmsg_type) {
681 		case RTM_NEWLINK:
682 			vlan_read_ifnames(h, plen, 0, hapd);
683 			break;
684 		case RTM_DELLINK:
685 			vlan_read_ifnames(h, plen, 1, hapd);
686 			break;
687 		}
688 
689 		h = NLMSG_NEXT(h, left);
690 	}
691 
692 	if (left > 0) {
693 		wpa_printf(MSG_DEBUG, "VLAN: %s: %d extra bytes in the end of "
694 			   "netlink message", __func__, left);
695 	}
696 }
697 
698 
699 struct full_dynamic_vlan *
700 full_dynamic_vlan_init(struct hostapd_data *hapd)
701 {
702 	struct sockaddr_nl local;
703 	struct full_dynamic_vlan *priv;
704 
705 	priv = os_zalloc(sizeof(*priv));
706 	if (priv == NULL)
707 		return NULL;
708 
709 	vlan_set_name_type(hapd->conf->ssid.vlan_naming ==
710 			   DYNAMIC_VLAN_NAMING_WITH_DEVICE ?
711 			   VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD :
712 			   VLAN_NAME_TYPE_PLUS_VID_NO_PAD);
713 
714 	priv->s = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
715 	if (priv->s < 0) {
716 		wpa_printf(MSG_ERROR, "VLAN: %s: socket(PF_NETLINK,SOCK_RAW,"
717 			   "NETLINK_ROUTE) failed: %s",
718 			   __func__, strerror(errno));
719 		os_free(priv);
720 		return NULL;
721 	}
722 
723 	os_memset(&local, 0, sizeof(local));
724 	local.nl_family = AF_NETLINK;
725 	local.nl_groups = RTMGRP_LINK;
726 	if (bind(priv->s, (struct sockaddr *) &local, sizeof(local)) < 0) {
727 		wpa_printf(MSG_ERROR, "VLAN: %s: bind(netlink) failed: %s",
728 			   __func__, strerror(errno));
729 		close(priv->s);
730 		os_free(priv);
731 		return NULL;
732 	}
733 
734 	if (eloop_register_read_sock(priv->s, vlan_event_receive, hapd, NULL))
735 	{
736 		close(priv->s);
737 		os_free(priv);
738 		return NULL;
739 	}
740 
741 	return priv;
742 }
743 
744 
745 void full_dynamic_vlan_deinit(struct full_dynamic_vlan *priv)
746 {
747 	if (priv == NULL)
748 		return;
749 	eloop_unregister_read_sock(priv->s);
750 	close(priv->s);
751 	os_free(priv);
752 }
753