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 "drivers/linux_ioctl.h"
20  #include "common/linux_bridge.h"
21  #include "common/linux_vlan.h"
22  #include "utils/eloop.h"
23  #include "hostapd.h"
24  #include "ap_config.h"
25  #include "ap_drv_ops.h"
26  #include "wpa_auth.h"
27  #include "vlan_init.h"
28  #include "vlan_util.h"
29  
30  
31  struct full_dynamic_vlan {
32  	int s; /* socket on which to listen for new/removed interfaces. */
33  };
34  
35  #define DVLAN_CLEAN_BR         0x1
36  #define DVLAN_CLEAN_VLAN       0x2
37  #define DVLAN_CLEAN_VLAN_PORT  0x4
38  
39  struct dynamic_iface {
40  	char ifname[IFNAMSIZ + 1];
41  	int usage;
42  	int clean;
43  	struct dynamic_iface *next;
44  };
45  
46  
47  /* Increment ref counter for ifname and add clean flag.
48   * If not in list, add it only if some flags are given.
49   */
dyn_iface_get(struct hostapd_data * hapd,const char * ifname,int clean)50  static void dyn_iface_get(struct hostapd_data *hapd, const char *ifname,
51  			  int clean)
52  {
53  	struct dynamic_iface *next, **dynamic_ifaces;
54  	struct hapd_interfaces *interfaces;
55  
56  	interfaces = hapd->iface->interfaces;
57  	dynamic_ifaces = &interfaces->vlan_priv;
58  
59  	for (next = *dynamic_ifaces; next; next = next->next) {
60  		if (os_strcmp(ifname, next->ifname) == 0)
61  			break;
62  	}
63  
64  	if (next) {
65  		next->usage++;
66  		next->clean |= clean;
67  		return;
68  	}
69  
70  	if (!clean)
71  		return;
72  
73  	next = os_zalloc(sizeof(*next));
74  	if (!next)
75  		return;
76  	os_strlcpy(next->ifname, ifname, sizeof(next->ifname));
77  	next->usage = 1;
78  	next->clean = clean;
79  	next->next = *dynamic_ifaces;
80  	*dynamic_ifaces = next;
81  }
82  
83  
84  /* Decrement reference counter for given ifname.
85   * Return clean flag iff reference counter was decreased to zero, else zero
86   */
dyn_iface_put(struct hostapd_data * hapd,const char * ifname)87  static int dyn_iface_put(struct hostapd_data *hapd, const char *ifname)
88  {
89  	struct dynamic_iface *next, *prev = NULL, **dynamic_ifaces;
90  	struct hapd_interfaces *interfaces;
91  	int clean;
92  
93  	interfaces = hapd->iface->interfaces;
94  	dynamic_ifaces = &interfaces->vlan_priv;
95  
96  	for (next = *dynamic_ifaces; next; next = next->next) {
97  		if (os_strcmp(ifname, next->ifname) == 0)
98  			break;
99  		prev = next;
100  	}
101  
102  	if (!next)
103  		return 0;
104  
105  	next->usage--;
106  	if (next->usage)
107  		return 0;
108  
109  	if (prev)
110  		prev->next = next->next;
111  	else
112  		*dynamic_ifaces = next->next;
113  	clean = next->clean;
114  	os_free(next);
115  
116  	return clean;
117  }
118  
119  
ifconfig_down(const char * if_name)120  static int ifconfig_down(const char *if_name)
121  {
122  	wpa_printf(MSG_DEBUG, "VLAN: Set interface %s down", if_name);
123  	return ifconfig_helper(if_name, 0);
124  }
125  
126  
127  /* This value should be 256 ONLY. If it is something else, then hostapd
128   * might crash!, as this value has been hard-coded in 2.4.x kernel
129   * bridging code.
130   */
131  #define MAX_BR_PORTS      		256
132  
br_delif(const char * br_name,const char * if_name)133  static int br_delif(const char *br_name, const char *if_name)
134  {
135  	int fd;
136  	struct ifreq ifr;
137  	unsigned long args[2];
138  	int if_index;
139  
140  	wpa_printf(MSG_DEBUG, "VLAN: br_delif(%s, %s)", br_name, if_name);
141  	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
142  		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
143  			   "failed: %s", __func__, strerror(errno));
144  		return -1;
145  	}
146  
147  	if (linux_br_del_if(fd, br_name, if_name) == 0)
148  		goto done;
149  
150  	if_index = if_nametoindex(if_name);
151  
152  	if (if_index == 0) {
153  		wpa_printf(MSG_ERROR, "VLAN: %s: Failure determining "
154  			   "interface index for '%s'",
155  			   __func__, if_name);
156  		close(fd);
157  		return -1;
158  	}
159  
160  	args[0] = BRCTL_DEL_IF;
161  	args[1] = if_index;
162  
163  	os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
164  	ifr.ifr_data = (void *) args;
165  
166  	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0 && errno != EINVAL) {
167  		/* No error if interface already removed. */
168  		wpa_printf(MSG_ERROR, "VLAN: %s: ioctl[SIOCDEVPRIVATE,"
169  			   "BRCTL_DEL_IF] failed for br_name=%s if_name=%s: "
170  			   "%s", __func__, br_name, if_name, strerror(errno));
171  		close(fd);
172  		return -1;
173  	}
174  
175  done:
176  	close(fd);
177  	return 0;
178  }
179  
180  
181  /*
182  	Add interface 'if_name' to the bridge 'br_name'
183  
184  	returns -1 on error
185  	returns 1 if the interface is already part of the bridge
186  	returns 0 otherwise
187  */
br_addif(const char * br_name,const char * if_name)188  static int br_addif(const char *br_name, const char *if_name)
189  {
190  	int fd;
191  	struct ifreq ifr;
192  	unsigned long args[2];
193  	int if_index;
194  
195  	wpa_printf(MSG_DEBUG, "VLAN: br_addif(%s, %s)", br_name, if_name);
196  	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
197  		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
198  			   "failed: %s", __func__, strerror(errno));
199  		return -1;
200  	}
201  
202  	if (linux_br_add_if(fd, br_name, if_name) == 0)
203  		goto done;
204  	if (errno == EBUSY) {
205  		/* The interface is already added. */
206  		close(fd);
207  		return 1;
208  	}
209  
210  	if_index = if_nametoindex(if_name);
211  
212  	if (if_index == 0) {
213  		wpa_printf(MSG_ERROR, "VLAN: %s: Failure determining "
214  			   "interface index for '%s'",
215  			   __func__, if_name);
216  		close(fd);
217  		return -1;
218  	}
219  
220  	args[0] = BRCTL_ADD_IF;
221  	args[1] = if_index;
222  
223  	os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
224  	ifr.ifr_data = (void *) args;
225  
226  	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
227  		if (errno == EBUSY) {
228  			/* The interface is already added. */
229  			close(fd);
230  			return 1;
231  		}
232  
233  		wpa_printf(MSG_ERROR, "VLAN: %s: ioctl[SIOCDEVPRIVATE,"
234  			   "BRCTL_ADD_IF] failed for br_name=%s if_name=%s: "
235  			   "%s", __func__, br_name, if_name, strerror(errno));
236  		close(fd);
237  		return -1;
238  	}
239  
240  done:
241  	close(fd);
242  	return 0;
243  }
244  
245  
br_delbr(const char * br_name)246  static int br_delbr(const char *br_name)
247  {
248  	int fd;
249  	unsigned long arg[2];
250  
251  	wpa_printf(MSG_DEBUG, "VLAN: br_delbr(%s)", br_name);
252  	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
253  		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
254  			   "failed: %s", __func__, strerror(errno));
255  		return -1;
256  	}
257  
258  	if (linux_br_del(fd, br_name) == 0)
259  		goto done;
260  
261  	arg[0] = BRCTL_DEL_BRIDGE;
262  	arg[1] = (unsigned long) br_name;
263  
264  	if (ioctl(fd, SIOCGIFBR, arg) < 0 && errno != ENXIO) {
265  		/* No error if bridge already removed. */
266  		wpa_printf(MSG_ERROR, "VLAN: %s: BRCTL_DEL_BRIDGE failed for "
267  			   "%s: %s", __func__, br_name, strerror(errno));
268  		close(fd);
269  		return -1;
270  	}
271  
272  done:
273  	close(fd);
274  	return 0;
275  }
276  
277  
278  /*
279  	Add a bridge with the name 'br_name'.
280  
281  	returns -1 on error
282  	returns 1 if the bridge already exists
283  	returns 0 otherwise
284  */
br_addbr(const char * br_name)285  static int br_addbr(const char *br_name)
286  {
287  	int fd;
288  	unsigned long arg[4];
289  	struct ifreq ifr;
290  
291  	wpa_printf(MSG_DEBUG, "VLAN: br_addbr(%s)", br_name);
292  	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
293  		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
294  			   "failed: %s", __func__, strerror(errno));
295  		return -1;
296  	}
297  
298  	if (linux_br_add(fd, br_name) == 0)
299  		goto done;
300  	if (errno == EEXIST) {
301  		/* The bridge is already added. */
302  		close(fd);
303  		return 1;
304  	}
305  
306  	arg[0] = BRCTL_ADD_BRIDGE;
307  	arg[1] = (unsigned long) br_name;
308  
309  	if (ioctl(fd, SIOCGIFBR, arg) < 0) {
310  		if (errno == EEXIST) {
311  			/* The bridge is already added. */
312  			close(fd);
313  			return 1;
314  		} else {
315  			wpa_printf(MSG_ERROR, "VLAN: %s: BRCTL_ADD_BRIDGE "
316  				   "failed for %s: %s",
317  				   __func__, br_name, strerror(errno));
318  			close(fd);
319  			return -1;
320  		}
321  	}
322  
323  done:
324  	/* Decrease forwarding delay to avoid EAPOL timeouts. */
325  	os_memset(&ifr, 0, sizeof(ifr));
326  	os_strlcpy(ifr.ifr_name, br_name, IFNAMSIZ);
327  	arg[0] = BRCTL_SET_BRIDGE_FORWARD_DELAY;
328  	arg[1] = 1;
329  	arg[2] = 0;
330  	arg[3] = 0;
331  	ifr.ifr_data = (char *) &arg;
332  	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
333  		wpa_printf(MSG_ERROR, "VLAN: %s: "
334  			   "BRCTL_SET_BRIDGE_FORWARD_DELAY (1 sec) failed for "
335  			   "%s: %s", __func__, br_name, strerror(errno));
336  		/* Continue anyway */
337  	}
338  
339  	close(fd);
340  	return 0;
341  }
342  
343  
br_getnumports(const char * br_name)344  static int br_getnumports(const char *br_name)
345  {
346  	int fd;
347  	int i;
348  	int port_cnt = 0;
349  	unsigned long arg[4];
350  	int ifindices[MAX_BR_PORTS];
351  	struct ifreq ifr;
352  
353  	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
354  		wpa_printf(MSG_ERROR, "VLAN: %s: socket(AF_INET,SOCK_STREAM) "
355  			   "failed: %s", __func__, strerror(errno));
356  		return -1;
357  	}
358  
359  	arg[0] = BRCTL_GET_PORT_LIST;
360  	arg[1] = (unsigned long) ifindices;
361  	arg[2] = MAX_BR_PORTS;
362  	arg[3] = 0;
363  
364  	os_memset(ifindices, 0, sizeof(ifindices));
365  	os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
366  	ifr.ifr_data = (void *) arg;
367  
368  	if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
369  		wpa_printf(MSG_ERROR, "VLAN: %s: BRCTL_GET_PORT_LIST "
370  			   "failed for %s: %s",
371  			   __func__, br_name, strerror(errno));
372  		close(fd);
373  		return -1;
374  	}
375  
376  	for (i = 1; i < MAX_BR_PORTS; i++) {
377  		if (ifindices[i] > 0) {
378  			port_cnt++;
379  		}
380  	}
381  
382  	close(fd);
383  	return port_cnt;
384  }
385  
386  
vlan_newlink_tagged(int vlan_naming,const char * tagged_interface,const char * br_name,int vid,struct hostapd_data * hapd)387  static void vlan_newlink_tagged(int vlan_naming, const char *tagged_interface,
388  				const char *br_name, int vid,
389  				struct hostapd_data *hapd)
390  {
391  	char vlan_ifname[IFNAMSIZ];
392  	int clean;
393  	int ret;
394  
395  	if (vlan_naming == DYNAMIC_VLAN_NAMING_WITH_DEVICE)
396  		ret = os_snprintf(vlan_ifname, sizeof(vlan_ifname), "%s.%d",
397  				  tagged_interface, vid);
398  	else
399  		ret = os_snprintf(vlan_ifname, sizeof(vlan_ifname), "vlan%d",
400  				  vid);
401  	if (ret >= (int) sizeof(vlan_ifname))
402  		wpa_printf(MSG_WARNING,
403  			   "VLAN: Interface name was truncated to %s",
404  			   vlan_ifname);
405  
406  	clean = 0;
407  	ifconfig_up(tagged_interface);
408  	if (!vlan_add(tagged_interface, vid, vlan_ifname))
409  		clean |= DVLAN_CLEAN_VLAN;
410  
411  	if (!br_addif(br_name, vlan_ifname))
412  		clean |= DVLAN_CLEAN_VLAN_PORT;
413  
414  	dyn_iface_get(hapd, vlan_ifname, clean);
415  
416  	ifconfig_up(vlan_ifname);
417  }
418  
419  
vlan_bridge_name(char * br_name,struct hostapd_data * hapd,struct hostapd_vlan * vlan,int vid)420  static void vlan_bridge_name(char *br_name, struct hostapd_data *hapd,
421  			     struct hostapd_vlan *vlan, int vid)
422  {
423  	char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;
424  	int ret;
425  
426  	if (vlan->bridge[0]) {
427  		os_strlcpy(br_name, vlan->bridge, IFNAMSIZ);
428  		ret = 0;
429  	} else if (hapd->conf->vlan_bridge[0]) {
430  		ret = os_snprintf(br_name, IFNAMSIZ, "%s%d",
431  				  hapd->conf->vlan_bridge, vid);
432  	} else if (tagged_interface) {
433  		ret = os_snprintf(br_name, IFNAMSIZ, "br%s.%d",
434  				  tagged_interface, vid);
435  	} else {
436  		ret = os_snprintf(br_name, IFNAMSIZ, "brvlan%d", vid);
437  	}
438  	if (ret >= IFNAMSIZ)
439  		wpa_printf(MSG_WARNING,
440  			   "VLAN: Interface name was truncated to %s",
441  			   br_name);
442  }
443  
444  
vlan_get_bridge(const char * br_name,struct hostapd_data * hapd,int vid)445  static void vlan_get_bridge(const char *br_name, struct hostapd_data *hapd,
446  			    int vid)
447  {
448  	char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;
449  	int vlan_naming = hapd->conf->ssid.vlan_naming;
450  
451  	dyn_iface_get(hapd, br_name, br_addbr(br_name) ? 0 : DVLAN_CLEAN_BR);
452  
453  	ifconfig_up(br_name);
454  
455  	if (tagged_interface)
456  		vlan_newlink_tagged(vlan_naming, tagged_interface, br_name,
457  				    vid, hapd);
458  }
459  
460  
vlan_newlink(const char * ifname,struct hostapd_data * hapd)461  void vlan_newlink(const char *ifname, struct hostapd_data *hapd)
462  {
463  	char br_name[IFNAMSIZ];
464  	struct hostapd_vlan *vlan;
465  	int untagged, *tagged, i, notempty;
466  
467  	wpa_printf(MSG_DEBUG, "VLAN: vlan_newlink(%s)", ifname);
468  
469  	for (vlan = hapd->conf->vlan; vlan; vlan = vlan->next) {
470  		if (vlan->configured ||
471  		    os_strcmp(ifname, vlan->ifname) != 0)
472  			continue;
473  		break;
474  	}
475  	if (!vlan)
476  		return;
477  
478  	vlan->configured = 1;
479  
480  	notempty = vlan->vlan_desc.notempty;
481  	untagged = vlan->vlan_desc.untagged;
482  	tagged = vlan->vlan_desc.tagged;
483  
484  	if (!notempty) {
485  		/* Non-VLAN STA */
486  		if (hapd->conf->bridge[0] &&
487  		    !br_addif(hapd->conf->bridge, ifname))
488  			vlan->clean |= DVLAN_CLEAN_WLAN_PORT;
489  	} else if (untagged > 0 && untagged <= MAX_VLAN_ID) {
490  		vlan_bridge_name(br_name, hapd, vlan, untagged);
491  
492  		vlan_get_bridge(br_name, hapd, untagged);
493  
494  		if (!br_addif(br_name, ifname))
495  			vlan->clean |= DVLAN_CLEAN_WLAN_PORT;
496  	}
497  
498  	for (i = 0; i < MAX_NUM_TAGGED_VLAN && tagged[i]; i++) {
499  		if (tagged[i] == untagged ||
500  		    tagged[i] <= 0 || tagged[i] > MAX_VLAN_ID ||
501  		    (i > 0 && tagged[i] == tagged[i - 1]))
502  			continue;
503  		vlan_bridge_name(br_name, hapd, vlan, tagged[i]);
504  		vlan_get_bridge(br_name, hapd, tagged[i]);
505  		vlan_newlink_tagged(DYNAMIC_VLAN_NAMING_WITH_DEVICE,
506  				    ifname, br_name, tagged[i], hapd);
507  	}
508  
509  	ifconfig_up(ifname);
510  }
511  
512  
vlan_dellink_tagged(int vlan_naming,const char * tagged_interface,const char * br_name,int vid,struct hostapd_data * hapd)513  static void vlan_dellink_tagged(int vlan_naming, const char *tagged_interface,
514  				const char *br_name, int vid,
515  				struct hostapd_data *hapd)
516  {
517  	char vlan_ifname[IFNAMSIZ];
518  	int clean;
519  	int ret;
520  
521  	if (vlan_naming == DYNAMIC_VLAN_NAMING_WITH_DEVICE)
522  		ret = os_snprintf(vlan_ifname, sizeof(vlan_ifname), "%s.%d",
523  				  tagged_interface, vid);
524  	else
525  		ret = os_snprintf(vlan_ifname, sizeof(vlan_ifname), "vlan%d",
526  				  vid);
527  	if (ret >= (int) sizeof(vlan_ifname))
528  		wpa_printf(MSG_WARNING,
529  			   "VLAN: Interface name was truncated to %s",
530  			   vlan_ifname);
531  
532  
533  	clean = dyn_iface_put(hapd, vlan_ifname);
534  
535  	if (clean & DVLAN_CLEAN_VLAN_PORT)
536  		br_delif(br_name, vlan_ifname);
537  
538  	if (clean & DVLAN_CLEAN_VLAN) {
539  		ifconfig_down(vlan_ifname);
540  		vlan_rem(vlan_ifname);
541  	}
542  }
543  
544  
vlan_put_bridge(const char * br_name,struct hostapd_data * hapd,int vid)545  static void vlan_put_bridge(const char *br_name, struct hostapd_data *hapd,
546  			    int vid)
547  {
548  	int clean;
549  	char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;
550  	int vlan_naming = hapd->conf->ssid.vlan_naming;
551  
552  	if (tagged_interface)
553  		vlan_dellink_tagged(vlan_naming, tagged_interface, br_name,
554  				    vid, hapd);
555  
556  	clean = dyn_iface_put(hapd, br_name);
557  	if ((clean & DVLAN_CLEAN_BR) && br_getnumports(br_name) == 0) {
558  		ifconfig_down(br_name);
559  		br_delbr(br_name);
560  	}
561  }
562  
563  
vlan_dellink(const char * ifname,struct hostapd_data * hapd)564  void vlan_dellink(const char *ifname, struct hostapd_data *hapd)
565  {
566  	struct hostapd_vlan *first, *prev, *vlan = hapd->conf->vlan;
567  
568  	wpa_printf(MSG_DEBUG, "VLAN: vlan_dellink(%s)", ifname);
569  
570  	first = prev = vlan;
571  
572  	while (vlan) {
573  		if (os_strcmp(ifname, vlan->ifname) != 0) {
574  			prev = vlan;
575  			vlan = vlan->next;
576  			continue;
577  		}
578  		break;
579  	}
580  	if (!vlan)
581  		return;
582  
583  	if (vlan->configured) {
584  		int notempty = vlan->vlan_desc.notempty;
585  		int untagged = vlan->vlan_desc.untagged;
586  		int *tagged = vlan->vlan_desc.tagged;
587  		char br_name[IFNAMSIZ];
588  		int i;
589  
590  		for (i = 0; i < MAX_NUM_TAGGED_VLAN && tagged[i]; i++) {
591  			if (tagged[i] == untagged ||
592  			    tagged[i] <= 0 || tagged[i] > MAX_VLAN_ID ||
593  			    (i > 0 && tagged[i] == tagged[i - 1]))
594  				continue;
595  			vlan_bridge_name(br_name, hapd, vlan, tagged[i]);
596  			vlan_dellink_tagged(DYNAMIC_VLAN_NAMING_WITH_DEVICE,
597  					    ifname, br_name, tagged[i], hapd);
598  			vlan_put_bridge(br_name, hapd, tagged[i]);
599  		}
600  
601  		if (!notempty) {
602  			/* Non-VLAN STA */
603  			if (hapd->conf->bridge[0] &&
604  			    (vlan->clean & DVLAN_CLEAN_WLAN_PORT))
605  				br_delif(hapd->conf->bridge, ifname);
606  		} else if (untagged > 0 && untagged <= MAX_VLAN_ID) {
607  			vlan_bridge_name(br_name, hapd, vlan, untagged);
608  
609  			if (vlan->clean & DVLAN_CLEAN_WLAN_PORT)
610  				br_delif(br_name, vlan->ifname);
611  
612  			vlan_put_bridge(br_name, hapd, untagged);
613  		}
614  	}
615  
616  	/*
617  	 * Ensure this VLAN interface is actually removed even if
618  	 * NEWLINK message is only received later.
619  	 */
620  	if (if_nametoindex(vlan->ifname) && vlan_if_remove(hapd, vlan))
621  		wpa_printf(MSG_ERROR,
622  			   "VLAN: Could not remove VLAN iface: %s: %s",
623  			   vlan->ifname, strerror(errno));
624  
625  	if (vlan == first)
626  		hapd->conf->vlan = vlan->next;
627  	else
628  		prev->next = vlan->next;
629  
630  	os_free(vlan);
631  }
632  
633  
634  static void
vlan_read_ifnames(struct nlmsghdr * h,size_t len,int del,struct hostapd_data * hapd)635  vlan_read_ifnames(struct nlmsghdr *h, size_t len, int del,
636  		  struct hostapd_data *hapd)
637  {
638  	struct ifinfomsg *ifi;
639  	int attrlen, nlmsg_len, rta_len;
640  	struct rtattr *attr;
641  	char ifname[IFNAMSIZ + 1];
642  
643  	if (len < sizeof(*ifi))
644  		return;
645  
646  	ifi = NLMSG_DATA(h);
647  
648  	nlmsg_len = NLMSG_ALIGN(sizeof(struct ifinfomsg));
649  
650  	attrlen = h->nlmsg_len - nlmsg_len;
651  	if (attrlen < 0)
652  		return;
653  
654  	attr = (struct rtattr *) (((char *) ifi) + nlmsg_len);
655  
656  	os_memset(ifname, 0, sizeof(ifname));
657  	rta_len = RTA_ALIGN(sizeof(struct rtattr));
658  	while (RTA_OK(attr, attrlen)) {
659  		if (attr->rta_type == IFLA_IFNAME) {
660  			int n = attr->rta_len - rta_len;
661  			if (n < 0)
662  				break;
663  
664  			if ((size_t) n >= sizeof(ifname))
665  				n = sizeof(ifname) - 1;
666  			os_memcpy(ifname, ((char *) attr) + rta_len, n);
667  
668  		}
669  
670  		attr = RTA_NEXT(attr, attrlen);
671  	}
672  
673  	if (!ifname[0])
674  		return;
675  	if (del && if_nametoindex(ifname)) {
676  		 /* interface still exists, race condition ->
677  		  * iface has just been recreated */
678  		return;
679  	}
680  
681  	wpa_printf(MSG_DEBUG,
682  		   "VLAN: RTM_%sLINK: ifi_index=%d ifname=%s ifi_family=%d ifi_flags=0x%x (%s%s%s%s)",
683  		   del ? "DEL" : "NEW",
684  		   ifi->ifi_index, ifname, ifi->ifi_family, ifi->ifi_flags,
685  		   (ifi->ifi_flags & IFF_UP) ? "[UP]" : "",
686  		   (ifi->ifi_flags & IFF_RUNNING) ? "[RUNNING]" : "",
687  		   (ifi->ifi_flags & IFF_LOWER_UP) ? "[LOWER_UP]" : "",
688  		   (ifi->ifi_flags & IFF_DORMANT) ? "[DORMANT]" : "");
689  
690  	if (del)
691  		vlan_dellink(ifname, hapd);
692  	else
693  		vlan_newlink(ifname, hapd);
694  }
695  
696  
vlan_event_receive(int sock,void * eloop_ctx,void * sock_ctx)697  static void vlan_event_receive(int sock, void *eloop_ctx, void *sock_ctx)
698  {
699  	char buf[8192];
700  	int left;
701  	struct sockaddr_nl from;
702  	socklen_t fromlen;
703  	struct nlmsghdr *h;
704  	struct hostapd_data *hapd = eloop_ctx;
705  
706  	fromlen = sizeof(from);
707  	left = recvfrom(sock, buf, sizeof(buf), MSG_DONTWAIT,
708  			(struct sockaddr *) &from, &fromlen);
709  	if (left < 0) {
710  		if (errno != EINTR && errno != EAGAIN)
711  			wpa_printf(MSG_ERROR, "VLAN: %s: recvfrom failed: %s",
712  				   __func__, strerror(errno));
713  		return;
714  	}
715  
716  	h = (struct nlmsghdr *) buf;
717  	while (NLMSG_OK(h, left)) {
718  		int len, plen;
719  
720  		len = h->nlmsg_len;
721  		plen = len - sizeof(*h);
722  		if (len > left || plen < 0) {
723  			wpa_printf(MSG_DEBUG, "VLAN: Malformed netlink "
724  				   "message: len=%d left=%d plen=%d",
725  				   len, left, plen);
726  			break;
727  		}
728  
729  		switch (h->nlmsg_type) {
730  		case RTM_NEWLINK:
731  			vlan_read_ifnames(h, plen, 0, hapd);
732  			break;
733  		case RTM_DELLINK:
734  			vlan_read_ifnames(h, plen, 1, hapd);
735  			break;
736  		}
737  
738  		h = NLMSG_NEXT(h, left);
739  	}
740  
741  	if (left > 0) {
742  		wpa_printf(MSG_DEBUG, "VLAN: %s: %d extra bytes in the end of "
743  			   "netlink message", __func__, left);
744  	}
745  }
746  
747  
748  struct full_dynamic_vlan *
full_dynamic_vlan_init(struct hostapd_data * hapd)749  full_dynamic_vlan_init(struct hostapd_data *hapd)
750  {
751  	struct sockaddr_nl local;
752  	struct full_dynamic_vlan *priv;
753  
754  	priv = os_zalloc(sizeof(*priv));
755  	if (priv == NULL)
756  		return NULL;
757  
758  	vlan_set_name_type(hapd->conf->ssid.vlan_naming ==
759  			   DYNAMIC_VLAN_NAMING_WITH_DEVICE ?
760  			   VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD :
761  			   VLAN_NAME_TYPE_PLUS_VID_NO_PAD);
762  
763  	priv->s = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
764  	if (priv->s < 0) {
765  		wpa_printf(MSG_ERROR, "VLAN: %s: socket(PF_NETLINK,SOCK_RAW,"
766  			   "NETLINK_ROUTE) failed: %s",
767  			   __func__, strerror(errno));
768  		os_free(priv);
769  		return NULL;
770  	}
771  
772  	os_memset(&local, 0, sizeof(local));
773  	local.nl_family = AF_NETLINK;
774  	local.nl_groups = RTMGRP_LINK;
775  	if (bind(priv->s, (struct sockaddr *) &local, sizeof(local)) < 0) {
776  		wpa_printf(MSG_ERROR, "VLAN: %s: bind(netlink) failed: %s",
777  			   __func__, strerror(errno));
778  		close(priv->s);
779  		os_free(priv);
780  		return NULL;
781  	}
782  
783  	if (eloop_register_read_sock(priv->s, vlan_event_receive, hapd, NULL))
784  	{
785  		close(priv->s);
786  		os_free(priv);
787  		return NULL;
788  	}
789  
790  	return priv;
791  }
792  
793  
full_dynamic_vlan_deinit(struct full_dynamic_vlan * priv)794  void full_dynamic_vlan_deinit(struct full_dynamic_vlan *priv)
795  {
796  	if (priv == NULL)
797  		return;
798  	eloop_unregister_read_sock(priv->s);
799  	close(priv->s);
800  	os_free(priv);
801  }
802