1 /*
2  * RADIUS client
3  * Copyright (c) 2002-2015, Jouni Malinen <j@w1.fi>
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8 
9 #include "includes.h"
10 
11 #include "common.h"
12 #include "radius.h"
13 #include "radius_client.h"
14 #include "eloop.h"
15 
16 /* Defaults for RADIUS retransmit values (exponential backoff) */
17 
18 /**
19  * RADIUS_CLIENT_FIRST_WAIT - RADIUS client timeout for first retry in seconds
20  */
21 #define RADIUS_CLIENT_FIRST_WAIT 3
22 
23 /**
24  * RADIUS_CLIENT_MAX_WAIT - RADIUS client maximum retry timeout in seconds
25  */
26 #define RADIUS_CLIENT_MAX_WAIT 120
27 
28 /**
29  * RADIUS_CLIENT_MAX_FAILOVER - RADIUS client maximum retries
30  *
31  * Maximum number of server failovers before the entry is removed from
32  * retransmit list.
33  */
34 #define RADIUS_CLIENT_MAX_FAILOVER 3
35 
36 /**
37  * RADIUS_CLIENT_MAX_ENTRIES - RADIUS client maximum pending messages
38  *
39  * Maximum number of entries in retransmit list (oldest entries will be
40  * removed, if this limit is exceeded).
41  */
42 #define RADIUS_CLIENT_MAX_ENTRIES 30
43 
44 /**
45  * RADIUS_CLIENT_NUM_FAILOVER - RADIUS client failover point
46  *
47  * The number of failed retry attempts after which the RADIUS server will be
48  * changed (if one of more backup servers are configured).
49  */
50 #define RADIUS_CLIENT_NUM_FAILOVER 4
51 
52 
53 /**
54  * struct radius_rx_handler - RADIUS client RX handler
55  *
56  * This data structure is used internally inside the RADIUS client module to
57  * store registered RX handlers. These handlers are registered by calls to
58  * radius_client_register() and unregistered when the RADIUS client is
59  * deinitialized with a call to radius_client_deinit().
60  */
61 struct radius_rx_handler {
62 	/**
63 	 * handler - Received RADIUS message handler
64 	 */
65 	RadiusRxResult (*handler)(struct radius_msg *msg,
66 				  struct radius_msg *req,
67 				  const u8 *shared_secret,
68 				  size_t shared_secret_len,
69 				  void *data);
70 
71 	/**
72 	 * data - Context data for the handler
73 	 */
74 	void *data;
75 };
76 
77 
78 /**
79  * struct radius_msg_list - RADIUS client message retransmit list
80  *
81  * This data structure is used internally inside the RADIUS client module to
82  * store pending RADIUS requests that may still need to be retransmitted.
83  */
84 struct radius_msg_list {
85 	/**
86 	 * addr - STA/client address
87 	 *
88 	 * This is used to find RADIUS messages for the same STA.
89 	 */
90 	u8 addr[ETH_ALEN];
91 
92 	/**
93 	 * msg - RADIUS message
94 	 */
95 	struct radius_msg *msg;
96 
97 	/**
98 	 * msg_type - Message type
99 	 */
100 	RadiusType msg_type;
101 
102 	/**
103 	 * first_try - Time of the first transmission attempt
104 	 */
105 	os_time_t first_try;
106 
107 	/**
108 	 * next_try - Time for the next transmission attempt
109 	 */
110 	os_time_t next_try;
111 
112 	/**
113 	 * attempts - Number of transmission attempts for one server
114 	 */
115 	int attempts;
116 
117 	/**
118 	 * accu_attempts - Number of accumulated attempts
119 	 */
120 	int accu_attempts;
121 
122 	/**
123 	 * next_wait - Next retransmission wait time in seconds
124 	 */
125 	int next_wait;
126 
127 	/**
128 	 * last_attempt - Time of the last transmission attempt
129 	 */
130 	struct os_reltime last_attempt;
131 
132 	/**
133 	 * shared_secret - Shared secret with the target RADIUS server
134 	 */
135 	const u8 *shared_secret;
136 
137 	/**
138 	 * shared_secret_len - shared_secret length in octets
139 	 */
140 	size_t shared_secret_len;
141 
142 	/* TODO: server config with failover to backup server(s) */
143 
144 	/**
145 	 * next - Next message in the list
146 	 */
147 	struct radius_msg_list *next;
148 };
149 
150 
151 /**
152  * struct radius_client_data - Internal RADIUS client data
153  *
154  * This data structure is used internally inside the RADIUS client module.
155  * External users allocate this by calling radius_client_init() and free it by
156  * calling radius_client_deinit(). The pointer to this opaque data is used in
157  * calls to other functions as an identifier for the RADIUS client instance.
158  */
159 struct radius_client_data {
160 	/**
161 	 * ctx - Context pointer for hostapd_logger() callbacks
162 	 */
163 	void *ctx;
164 
165 	/**
166 	 * conf - RADIUS client configuration (list of RADIUS servers to use)
167 	 */
168 	struct hostapd_radius_servers *conf;
169 
170 	/**
171 	 * auth_serv_sock - IPv4 socket for RADIUS authentication messages
172 	 */
173 	int auth_serv_sock;
174 
175 	/**
176 	 * acct_serv_sock - IPv4 socket for RADIUS accounting messages
177 	 */
178 	int acct_serv_sock;
179 
180 	/**
181 	 * auth_serv_sock6 - IPv6 socket for RADIUS authentication messages
182 	 */
183 	int auth_serv_sock6;
184 
185 	/**
186 	 * acct_serv_sock6 - IPv6 socket for RADIUS accounting messages
187 	 */
188 	int acct_serv_sock6;
189 
190 	/**
191 	 * auth_sock - Currently used socket for RADIUS authentication server
192 	 */
193 	int auth_sock;
194 
195 	/**
196 	 * acct_sock - Currently used socket for RADIUS accounting server
197 	 */
198 	int acct_sock;
199 
200 	/**
201 	 * auth_handlers - Authentication message handlers
202 	 */
203 	struct radius_rx_handler *auth_handlers;
204 
205 	/**
206 	 * num_auth_handlers - Number of handlers in auth_handlers
207 	 */
208 	size_t num_auth_handlers;
209 
210 	/**
211 	 * acct_handlers - Accounting message handlers
212 	 */
213 	struct radius_rx_handler *acct_handlers;
214 
215 	/**
216 	 * num_acct_handlers - Number of handlers in acct_handlers
217 	 */
218 	size_t num_acct_handlers;
219 
220 	/**
221 	 * msgs - Pending outgoing RADIUS messages
222 	 */
223 	struct radius_msg_list *msgs;
224 
225 	/**
226 	 * num_msgs - Number of pending messages in the msgs list
227 	 */
228 	size_t num_msgs;
229 
230 	/**
231 	 * next_radius_identifier - Next RADIUS message identifier to use
232 	 */
233 	u8 next_radius_identifier;
234 
235 	/**
236 	 * interim_error_cb - Interim accounting error callback
237 	 */
238 	void (*interim_error_cb)(const u8 *addr, void *ctx);
239 
240 	/**
241 	 * interim_error_cb_ctx - interim_error_cb() context data
242 	 */
243 	void *interim_error_cb_ctx;
244 };
245 
246 
247 static int
248 radius_change_server(struct radius_client_data *radius,
249 		     struct hostapd_radius_server *nserv,
250 		     struct hostapd_radius_server *oserv,
251 		     int sock, int sock6, int auth);
252 static int radius_client_init_acct(struct radius_client_data *radius);
253 static int radius_client_init_auth(struct radius_client_data *radius);
254 static void radius_client_auth_failover(struct radius_client_data *radius);
255 static void radius_client_acct_failover(struct radius_client_data *radius);
256 
257 
258 static void radius_client_msg_free(struct radius_msg_list *req)
259 {
260 	radius_msg_free(req->msg);
261 	os_free(req);
262 }
263 
264 
265 /**
266  * radius_client_register - Register a RADIUS client RX handler
267  * @radius: RADIUS client context from radius_client_init()
268  * @msg_type: RADIUS client type (RADIUS_AUTH or RADIUS_ACCT)
269  * @handler: Handler for received RADIUS messages
270  * @data: Context pointer for handler callbacks
271  * Returns: 0 on success, -1 on failure
272  *
273  * This function is used to register a handler for processing received RADIUS
274  * authentication and accounting messages. The handler() callback function will
275  * be called whenever a RADIUS message is received from the active server.
276  *
277  * There can be multiple registered RADIUS message handlers. The handlers will
278  * be called in order until one of them indicates that it has processed or
279  * queued the message.
280  */
281 int radius_client_register(struct radius_client_data *radius,
282 			   RadiusType msg_type,
283 			   RadiusRxResult (*handler)(struct radius_msg *msg,
284 						     struct radius_msg *req,
285 						     const u8 *shared_secret,
286 						     size_t shared_secret_len,
287 						     void *data),
288 			   void *data)
289 {
290 	struct radius_rx_handler **handlers, *newh;
291 	size_t *num;
292 
293 	if (msg_type == RADIUS_ACCT) {
294 		handlers = &radius->acct_handlers;
295 		num = &radius->num_acct_handlers;
296 	} else {
297 		handlers = &radius->auth_handlers;
298 		num = &radius->num_auth_handlers;
299 	}
300 
301 	newh = os_realloc_array(*handlers, *num + 1,
302 				sizeof(struct radius_rx_handler));
303 	if (newh == NULL)
304 		return -1;
305 
306 	newh[*num].handler = handler;
307 	newh[*num].data = data;
308 	(*num)++;
309 	*handlers = newh;
310 
311 	return 0;
312 }
313 
314 
315 /**
316  * radius_client_set_interim_erro_cb - Register an interim acct error callback
317  * @radius: RADIUS client context from radius_client_init()
318  * @addr: Station address from the failed message
319  * @cb: Handler for interim accounting errors
320  * @ctx: Context pointer for handler callbacks
321  *
322  * This function is used to register a handler for processing failed
323  * transmission attempts of interim accounting update messages.
324  */
325 void radius_client_set_interim_error_cb(struct radius_client_data *radius,
326 					void (*cb)(const u8 *addr, void *ctx),
327 					void *ctx)
328 {
329 	radius->interim_error_cb = cb;
330 	radius->interim_error_cb_ctx = ctx;
331 }
332 
333 
334 /*
335  * Returns >0 if message queue was flushed (i.e., the message that triggered
336  * the error is not available anymore)
337  */
338 static int radius_client_handle_send_error(struct radius_client_data *radius,
339 					   int s, RadiusType msg_type)
340 {
341 #ifndef CONFIG_NATIVE_WINDOWS
342 	int _errno = errno;
343 	wpa_printf(MSG_INFO, "send[RADIUS,s=%d]: %s", s, strerror(errno));
344 	if (_errno == ENOTCONN || _errno == EDESTADDRREQ || _errno == EINVAL ||
345 	    _errno == EBADF || _errno == ENETUNREACH || _errno == EACCES) {
346 		hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
347 			       HOSTAPD_LEVEL_INFO,
348 			       "Send failed - maybe interface status changed -"
349 			       " try to connect again");
350 		if (msg_type == RADIUS_ACCT ||
351 		    msg_type == RADIUS_ACCT_INTERIM) {
352 			radius_client_init_acct(radius);
353 			return 0;
354 		} else {
355 			radius_client_init_auth(radius);
356 			return 1;
357 		}
358 	}
359 #endif /* CONFIG_NATIVE_WINDOWS */
360 
361 	return 0;
362 }
363 
364 
365 static int radius_client_retransmit(struct radius_client_data *radius,
366 				    struct radius_msg_list *entry,
367 				    os_time_t now)
368 {
369 	struct hostapd_radius_servers *conf = radius->conf;
370 	int s;
371 	struct wpabuf *buf;
372 	size_t prev_num_msgs;
373 	u8 *acct_delay_time;
374 	size_t acct_delay_time_len;
375 	int num_servers;
376 
377 	if (entry->msg_type == RADIUS_ACCT ||
378 	    entry->msg_type == RADIUS_ACCT_INTERIM) {
379 		num_servers = conf->num_acct_servers;
380 		if (radius->acct_sock < 0)
381 			radius_client_init_acct(radius);
382 		if (radius->acct_sock < 0 && conf->num_acct_servers > 1) {
383 			prev_num_msgs = radius->num_msgs;
384 			radius_client_acct_failover(radius);
385 			if (prev_num_msgs != radius->num_msgs)
386 				return 0;
387 		}
388 		s = radius->acct_sock;
389 		if (entry->attempts == 0)
390 			conf->acct_server->requests++;
391 		else {
392 			conf->acct_server->timeouts++;
393 			conf->acct_server->retransmissions++;
394 		}
395 	} else {
396 		num_servers = conf->num_auth_servers;
397 		if (radius->auth_sock < 0)
398 			radius_client_init_auth(radius);
399 		if (radius->auth_sock < 0 && conf->num_auth_servers > 1) {
400 			prev_num_msgs = radius->num_msgs;
401 			radius_client_auth_failover(radius);
402 			if (prev_num_msgs != radius->num_msgs)
403 				return 0;
404 		}
405 		s = radius->auth_sock;
406 		if (entry->attempts == 0)
407 			conf->auth_server->requests++;
408 		else {
409 			conf->auth_server->timeouts++;
410 			conf->auth_server->retransmissions++;
411 		}
412 	}
413 
414 	if (entry->msg_type == RADIUS_ACCT_INTERIM) {
415 		wpa_printf(MSG_DEBUG,
416 			   "RADIUS: Failed to transmit interim accounting update to "
417 			   MACSTR " - drop message and request a new update",
418 			   MAC2STR(entry->addr));
419 		if (radius->interim_error_cb)
420 			radius->interim_error_cb(entry->addr,
421 						 radius->interim_error_cb_ctx);
422 		return 1;
423 	}
424 
425 	if (s < 0) {
426 		wpa_printf(MSG_INFO,
427 			   "RADIUS: No valid socket for retransmission");
428 		return 1;
429 	}
430 
431 	if (entry->msg_type == RADIUS_ACCT &&
432 	    radius_msg_get_attr_ptr(entry->msg, RADIUS_ATTR_ACCT_DELAY_TIME,
433 				    &acct_delay_time, &acct_delay_time_len,
434 				    NULL) == 0 &&
435 	    acct_delay_time_len == 4) {
436 		struct radius_hdr *hdr;
437 		u32 delay_time;
438 
439 		/*
440 		 * Need to assign a new identifier since attribute contents
441 		 * changes.
442 		 */
443 		hdr = radius_msg_get_hdr(entry->msg);
444 		hdr->identifier = radius_client_get_id(radius);
445 
446 		/* Update Acct-Delay-Time to show wait time in queue */
447 		delay_time = now - entry->first_try;
448 		WPA_PUT_BE32(acct_delay_time, delay_time);
449 
450 		wpa_printf(MSG_DEBUG,
451 			   "RADIUS: Updated Acct-Delay-Time to %u for retransmission",
452 			   delay_time);
453 		radius_msg_finish_acct(entry->msg, entry->shared_secret,
454 				       entry->shared_secret_len);
455 		if (radius->conf->msg_dumps)
456 			radius_msg_dump(entry->msg);
457 	}
458 
459 	/* retransmit; remove entry if too many attempts */
460 	if (entry->accu_attempts > RADIUS_CLIENT_MAX_FAILOVER *
461 	    RADIUS_CLIENT_NUM_FAILOVER * num_servers) {
462 		wpa_printf(MSG_INFO,
463 			   "RADIUS: Removing un-ACKed message due to too many failed retransmit attempts");
464 		return 1;
465 	}
466 
467 	entry->attempts++;
468 	entry->accu_attempts++;
469 	hostapd_logger(radius->ctx, entry->addr, HOSTAPD_MODULE_RADIUS,
470 		       HOSTAPD_LEVEL_DEBUG, "Resending RADIUS message (id=%d)",
471 		       radius_msg_get_hdr(entry->msg)->identifier);
472 
473 	os_get_reltime(&entry->last_attempt);
474 	buf = radius_msg_get_buf(entry->msg);
475 	if (send(s, wpabuf_head(buf), wpabuf_len(buf), 0) < 0) {
476 		if (radius_client_handle_send_error(radius, s, entry->msg_type)
477 		    > 0)
478 			return 0;
479 	}
480 
481 	entry->next_try = now + entry->next_wait;
482 	entry->next_wait *= 2;
483 	if (entry->next_wait > RADIUS_CLIENT_MAX_WAIT)
484 		entry->next_wait = RADIUS_CLIENT_MAX_WAIT;
485 
486 	return 0;
487 }
488 
489 
490 static void radius_client_timer(void *eloop_ctx, void *timeout_ctx)
491 {
492 	struct radius_client_data *radius = eloop_ctx;
493 	struct os_reltime now;
494 	os_time_t first;
495 	struct radius_msg_list *entry, *prev, *tmp;
496 	int auth_failover = 0, acct_failover = 0;
497 	size_t prev_num_msgs;
498 	int s;
499 
500 	entry = radius->msgs;
501 	if (!entry)
502 		return;
503 
504 	os_get_reltime(&now);
505 
506 	while (entry) {
507 		if (now.sec >= entry->next_try) {
508 			s = entry->msg_type == RADIUS_AUTH ? radius->auth_sock :
509 				radius->acct_sock;
510 			if (entry->attempts > RADIUS_CLIENT_NUM_FAILOVER ||
511 			    (s < 0 && entry->attempts > 0)) {
512 				if (entry->msg_type == RADIUS_ACCT ||
513 				    entry->msg_type == RADIUS_ACCT_INTERIM)
514 					acct_failover++;
515 				else
516 					auth_failover++;
517 			}
518 		}
519 		entry = entry->next;
520 	}
521 
522 	if (auth_failover)
523 		radius_client_auth_failover(radius);
524 
525 	if (acct_failover)
526 		radius_client_acct_failover(radius);
527 
528 	entry = radius->msgs;
529 	first = 0;
530 
531 	prev = NULL;
532 	while (entry) {
533 		prev_num_msgs = radius->num_msgs;
534 		if (now.sec >= entry->next_try &&
535 		    radius_client_retransmit(radius, entry, now.sec)) {
536 			if (prev)
537 				prev->next = entry->next;
538 			else
539 				radius->msgs = entry->next;
540 
541 			tmp = entry;
542 			entry = entry->next;
543 			radius_client_msg_free(tmp);
544 			radius->num_msgs--;
545 			continue;
546 		}
547 
548 		if (prev_num_msgs != radius->num_msgs) {
549 			wpa_printf(MSG_DEBUG,
550 				   "RADIUS: Message removed from queue - restart from beginning");
551 			entry = radius->msgs;
552 			prev = NULL;
553 			continue;
554 		}
555 
556 		if (first == 0 || entry->next_try < first)
557 			first = entry->next_try;
558 
559 		prev = entry;
560 		entry = entry->next;
561 	}
562 
563 	if (radius->msgs) {
564 		if (first < now.sec)
565 			first = now.sec;
566 		eloop_cancel_timeout(radius_client_timer, radius, NULL);
567 		eloop_register_timeout(first - now.sec, 0,
568 				       radius_client_timer, radius, NULL);
569 		hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
570 			       HOSTAPD_LEVEL_DEBUG, "Next RADIUS client "
571 			       "retransmit in %ld seconds",
572 			       (long int) (first - now.sec));
573 	}
574 }
575 
576 
577 static void radius_client_auth_failover(struct radius_client_data *radius)
578 {
579 	struct hostapd_radius_servers *conf = radius->conf;
580 	struct hostapd_radius_server *next, *old;
581 	struct radius_msg_list *entry;
582 	char abuf[50];
583 
584 	old = conf->auth_server;
585 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
586 		       HOSTAPD_LEVEL_NOTICE,
587 		       "No response from Authentication server %s:%d - failover",
588 		       hostapd_ip_txt(&old->addr, abuf, sizeof(abuf)),
589 		       old->port);
590 
591 	for (entry = radius->msgs; entry; entry = entry->next) {
592 		if (entry->msg_type == RADIUS_AUTH)
593 			old->timeouts++;
594 	}
595 
596 	next = old + 1;
597 	if (next > &(conf->auth_servers[conf->num_auth_servers - 1]))
598 		next = conf->auth_servers;
599 	conf->auth_server = next;
600 	radius_change_server(radius, next, old,
601 			     radius->auth_serv_sock,
602 			     radius->auth_serv_sock6, 1);
603 }
604 
605 
606 static void radius_client_acct_failover(struct radius_client_data *radius)
607 {
608 	struct hostapd_radius_servers *conf = radius->conf;
609 	struct hostapd_radius_server *next, *old;
610 	struct radius_msg_list *entry;
611 	char abuf[50];
612 
613 	old = conf->acct_server;
614 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
615 		       HOSTAPD_LEVEL_NOTICE,
616 		       "No response from Accounting server %s:%d - failover",
617 		       hostapd_ip_txt(&old->addr, abuf, sizeof(abuf)),
618 		       old->port);
619 
620 	for (entry = radius->msgs; entry; entry = entry->next) {
621 		if (entry->msg_type == RADIUS_ACCT ||
622 		    entry->msg_type == RADIUS_ACCT_INTERIM)
623 			old->timeouts++;
624 	}
625 
626 	next = old + 1;
627 	if (next > &conf->acct_servers[conf->num_acct_servers - 1])
628 		next = conf->acct_servers;
629 	conf->acct_server = next;
630 	radius_change_server(radius, next, old,
631 			     radius->acct_serv_sock,
632 			     radius->acct_serv_sock6, 0);
633 }
634 
635 
636 static void radius_client_update_timeout(struct radius_client_data *radius)
637 {
638 	struct os_reltime now;
639 	os_time_t first;
640 	struct radius_msg_list *entry;
641 
642 	eloop_cancel_timeout(radius_client_timer, radius, NULL);
643 
644 	if (radius->msgs == NULL) {
645 		return;
646 	}
647 
648 	first = 0;
649 	for (entry = radius->msgs; entry; entry = entry->next) {
650 		if (first == 0 || entry->next_try < first)
651 			first = entry->next_try;
652 	}
653 
654 	os_get_reltime(&now);
655 	if (first < now.sec)
656 		first = now.sec;
657 	eloop_register_timeout(first - now.sec, 0, radius_client_timer, radius,
658 			       NULL);
659 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
660 		       HOSTAPD_LEVEL_DEBUG, "Next RADIUS client retransmit in"
661 		       " %ld seconds", (long int) (first - now.sec));
662 }
663 
664 
665 static void radius_client_list_add(struct radius_client_data *radius,
666 				   struct radius_msg *msg,
667 				   RadiusType msg_type,
668 				   const u8 *shared_secret,
669 				   size_t shared_secret_len, const u8 *addr)
670 {
671 	struct radius_msg_list *entry, *prev;
672 
673 	if (eloop_terminated()) {
674 		/* No point in adding entries to retransmit queue since event
675 		 * loop has already been terminated. */
676 		radius_msg_free(msg);
677 		return;
678 	}
679 
680 	entry = os_zalloc(sizeof(*entry));
681 	if (entry == NULL) {
682 		wpa_printf(MSG_INFO, "RADIUS: Failed to add packet into retransmit list");
683 		radius_msg_free(msg);
684 		return;
685 	}
686 
687 	if (addr)
688 		os_memcpy(entry->addr, addr, ETH_ALEN);
689 	entry->msg = msg;
690 	entry->msg_type = msg_type;
691 	entry->shared_secret = shared_secret;
692 	entry->shared_secret_len = shared_secret_len;
693 	os_get_reltime(&entry->last_attempt);
694 	entry->first_try = entry->last_attempt.sec;
695 	entry->next_try = entry->first_try + RADIUS_CLIENT_FIRST_WAIT;
696 	entry->attempts = 1;
697 	entry->accu_attempts = 1;
698 	entry->next_wait = RADIUS_CLIENT_FIRST_WAIT * 2;
699 	if (entry->next_wait > RADIUS_CLIENT_MAX_WAIT)
700 		entry->next_wait = RADIUS_CLIENT_MAX_WAIT;
701 	entry->next = radius->msgs;
702 	radius->msgs = entry;
703 	radius_client_update_timeout(radius);
704 
705 	if (radius->num_msgs >= RADIUS_CLIENT_MAX_ENTRIES) {
706 		wpa_printf(MSG_INFO, "RADIUS: Removing the oldest un-ACKed packet due to retransmit list limits");
707 		prev = NULL;
708 		while (entry->next) {
709 			prev = entry;
710 			entry = entry->next;
711 		}
712 		if (prev) {
713 			prev->next = NULL;
714 			radius_client_msg_free(entry);
715 		}
716 	} else
717 		radius->num_msgs++;
718 }
719 
720 
721 /**
722  * radius_client_send - Send a RADIUS request
723  * @radius: RADIUS client context from radius_client_init()
724  * @msg: RADIUS message to be sent
725  * @msg_type: Message type (RADIUS_AUTH, RADIUS_ACCT, RADIUS_ACCT_INTERIM)
726  * @addr: MAC address of the device related to this message or %NULL
727  * Returns: 0 on success, -1 on failure
728  *
729  * This function is used to transmit a RADIUS authentication (RADIUS_AUTH) or
730  * accounting request (RADIUS_ACCT or RADIUS_ACCT_INTERIM). The only difference
731  * between accounting and interim accounting messages is that the interim
732  * message will not be retransmitted. Instead, a callback is used to indicate
733  * that the transmission failed for the specific station @addr so that a new
734  * interim accounting update message can be generated with up-to-date session
735  * data instead of trying to resend old information.
736  *
737  * The message is added on the retransmission queue and will be retransmitted
738  * automatically until a response is received or maximum number of retries
739  * (RADIUS_CLIENT_MAX_FAILOVER * RADIUS_CLIENT_NUM_FAILOVER) is reached. No
740  * such retries are used with RADIUS_ACCT_INTERIM, i.e., such a pending message
741  * is removed from the queue automatically on transmission failure.
742  *
743  * The related device MAC address can be used to identify pending messages that
744  * can be removed with radius_client_flush_auth().
745  */
746 int radius_client_send(struct radius_client_data *radius,
747 		       struct radius_msg *msg, RadiusType msg_type,
748 		       const u8 *addr)
749 {
750 	struct hostapd_radius_servers *conf = radius->conf;
751 	const u8 *shared_secret;
752 	size_t shared_secret_len;
753 	char *name;
754 	int s, res;
755 	struct wpabuf *buf;
756 
757 	if (msg_type == RADIUS_ACCT || msg_type == RADIUS_ACCT_INTERIM) {
758 		if (conf->acct_server && radius->acct_sock < 0)
759 			radius_client_init_acct(radius);
760 
761 		if (conf->acct_server == NULL || radius->acct_sock < 0 ||
762 		    conf->acct_server->shared_secret == NULL) {
763 			hostapd_logger(radius->ctx, NULL,
764 				       HOSTAPD_MODULE_RADIUS,
765 				       HOSTAPD_LEVEL_INFO,
766 				       "No accounting server configured");
767 			return -1;
768 		}
769 		shared_secret = conf->acct_server->shared_secret;
770 		shared_secret_len = conf->acct_server->shared_secret_len;
771 		radius_msg_finish_acct(msg, shared_secret, shared_secret_len);
772 		name = "accounting";
773 		s = radius->acct_sock;
774 		conf->acct_server->requests++;
775 	} else {
776 		if (conf->auth_server && radius->auth_sock < 0)
777 			radius_client_init_auth(radius);
778 
779 		if (conf->auth_server == NULL || radius->auth_sock < 0 ||
780 		    conf->auth_server->shared_secret == NULL) {
781 			hostapd_logger(radius->ctx, NULL,
782 				       HOSTAPD_MODULE_RADIUS,
783 				       HOSTAPD_LEVEL_INFO,
784 				       "No authentication server configured");
785 			return -1;
786 		}
787 		shared_secret = conf->auth_server->shared_secret;
788 		shared_secret_len = conf->auth_server->shared_secret_len;
789 		radius_msg_finish(msg, shared_secret, shared_secret_len);
790 		name = "authentication";
791 		s = radius->auth_sock;
792 		conf->auth_server->requests++;
793 	}
794 
795 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
796 		       HOSTAPD_LEVEL_DEBUG, "Sending RADIUS message to %s "
797 		       "server", name);
798 	if (conf->msg_dumps)
799 		radius_msg_dump(msg);
800 
801 	buf = radius_msg_get_buf(msg);
802 	res = send(s, wpabuf_head(buf), wpabuf_len(buf), 0);
803 	if (res < 0)
804 		radius_client_handle_send_error(radius, s, msg_type);
805 
806 	radius_client_list_add(radius, msg, msg_type, shared_secret,
807 			       shared_secret_len, addr);
808 
809 	return 0;
810 }
811 
812 
813 static void radius_client_receive(int sock, void *eloop_ctx, void *sock_ctx)
814 {
815 	struct radius_client_data *radius = eloop_ctx;
816 	struct hostapd_radius_servers *conf = radius->conf;
817 	RadiusType msg_type = (RadiusType) sock_ctx;
818 	int len, roundtrip;
819 	unsigned char buf[3000];
820 	struct radius_msg *msg;
821 	struct radius_hdr *hdr;
822 	struct radius_rx_handler *handlers;
823 	size_t num_handlers, i;
824 	struct radius_msg_list *req, *prev_req;
825 	struct os_reltime now;
826 	struct hostapd_radius_server *rconf;
827 	int invalid_authenticator = 0;
828 
829 	if (msg_type == RADIUS_ACCT) {
830 		handlers = radius->acct_handlers;
831 		num_handlers = radius->num_acct_handlers;
832 		rconf = conf->acct_server;
833 	} else {
834 		handlers = radius->auth_handlers;
835 		num_handlers = radius->num_auth_handlers;
836 		rconf = conf->auth_server;
837 	}
838 
839 	len = recv(sock, buf, sizeof(buf), MSG_DONTWAIT);
840 	if (len < 0) {
841 		wpa_printf(MSG_INFO, "recv[RADIUS]: %s", strerror(errno));
842 		return;
843 	}
844 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
845 		       HOSTAPD_LEVEL_DEBUG, "Received %d bytes from RADIUS "
846 		       "server", len);
847 	if (len == sizeof(buf)) {
848 		wpa_printf(MSG_INFO, "RADIUS: Possibly too long UDP frame for our buffer - dropping it");
849 		return;
850 	}
851 
852 	msg = radius_msg_parse(buf, len);
853 	if (msg == NULL) {
854 		wpa_printf(MSG_INFO, "RADIUS: Parsing incoming frame failed");
855 		rconf->malformed_responses++;
856 		return;
857 	}
858 	hdr = radius_msg_get_hdr(msg);
859 
860 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
861 		       HOSTAPD_LEVEL_DEBUG, "Received RADIUS message");
862 	if (conf->msg_dumps)
863 		radius_msg_dump(msg);
864 
865 	switch (hdr->code) {
866 	case RADIUS_CODE_ACCESS_ACCEPT:
867 		rconf->access_accepts++;
868 		break;
869 	case RADIUS_CODE_ACCESS_REJECT:
870 		rconf->access_rejects++;
871 		break;
872 	case RADIUS_CODE_ACCESS_CHALLENGE:
873 		rconf->access_challenges++;
874 		break;
875 	case RADIUS_CODE_ACCOUNTING_RESPONSE:
876 		rconf->responses++;
877 		break;
878 	}
879 
880 	prev_req = NULL;
881 	req = radius->msgs;
882 	while (req) {
883 		/* TODO: also match by src addr:port of the packet when using
884 		 * alternative RADIUS servers (?) */
885 		if ((req->msg_type == msg_type ||
886 		     (req->msg_type == RADIUS_ACCT_INTERIM &&
887 		      msg_type == RADIUS_ACCT)) &&
888 		    radius_msg_get_hdr(req->msg)->identifier ==
889 		    hdr->identifier)
890 			break;
891 
892 		prev_req = req;
893 		req = req->next;
894 	}
895 
896 	if (req == NULL) {
897 		hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
898 			       HOSTAPD_LEVEL_DEBUG,
899 			       "No matching RADIUS request found (type=%d "
900 			       "id=%d) - dropping packet",
901 			       msg_type, hdr->identifier);
902 		goto fail;
903 	}
904 
905 	os_get_reltime(&now);
906 	roundtrip = (now.sec - req->last_attempt.sec) * 100 +
907 		(now.usec - req->last_attempt.usec) / 10000;
908 	hostapd_logger(radius->ctx, req->addr, HOSTAPD_MODULE_RADIUS,
909 		       HOSTAPD_LEVEL_DEBUG,
910 		       "Received RADIUS packet matched with a pending "
911 		       "request, round trip time %d.%02d sec",
912 		       roundtrip / 100, roundtrip % 100);
913 	rconf->round_trip_time = roundtrip;
914 
915 	/* Remove ACKed RADIUS packet from retransmit list */
916 	if (prev_req)
917 		prev_req->next = req->next;
918 	else
919 		radius->msgs = req->next;
920 	radius->num_msgs--;
921 
922 	for (i = 0; i < num_handlers; i++) {
923 		RadiusRxResult res;
924 		res = handlers[i].handler(msg, req->msg, req->shared_secret,
925 					  req->shared_secret_len,
926 					  handlers[i].data);
927 		switch (res) {
928 		case RADIUS_RX_PROCESSED:
929 			radius_msg_free(msg);
930 			/* fall through */
931 		case RADIUS_RX_QUEUED:
932 			radius_client_msg_free(req);
933 			return;
934 		case RADIUS_RX_INVALID_AUTHENTICATOR:
935 			invalid_authenticator++;
936 			/* fall through */
937 		case RADIUS_RX_UNKNOWN:
938 			/* continue with next handler */
939 			break;
940 		}
941 	}
942 
943 	if (invalid_authenticator)
944 		rconf->bad_authenticators++;
945 	else
946 		rconf->unknown_types++;
947 	hostapd_logger(radius->ctx, req->addr, HOSTAPD_MODULE_RADIUS,
948 		       HOSTAPD_LEVEL_DEBUG, "No RADIUS RX handler found "
949 		       "(type=%d code=%d id=%d)%s - dropping packet",
950 		       msg_type, hdr->code, hdr->identifier,
951 		       invalid_authenticator ? " [INVALID AUTHENTICATOR]" :
952 		       "");
953 	radius_client_msg_free(req);
954 
955  fail:
956 	radius_msg_free(msg);
957 }
958 
959 
960 /**
961  * radius_client_get_id - Get an identifier for a new RADIUS message
962  * @radius: RADIUS client context from radius_client_init()
963  * Returns: Allocated identifier
964  *
965  * This function is used to fetch a unique (among pending requests) identifier
966  * for a new RADIUS message.
967  */
968 u8 radius_client_get_id(struct radius_client_data *radius)
969 {
970 	struct radius_msg_list *entry, *prev, *_remove;
971 	u8 id = radius->next_radius_identifier++;
972 
973 	/* remove entries with matching id from retransmit list to avoid
974 	 * using new reply from the RADIUS server with an old request */
975 	entry = radius->msgs;
976 	prev = NULL;
977 	while (entry) {
978 		if (radius_msg_get_hdr(entry->msg)->identifier == id) {
979 			hostapd_logger(radius->ctx, entry->addr,
980 				       HOSTAPD_MODULE_RADIUS,
981 				       HOSTAPD_LEVEL_DEBUG,
982 				       "Removing pending RADIUS message, "
983 				       "since its id (%d) is reused", id);
984 			if (prev)
985 				prev->next = entry->next;
986 			else
987 				radius->msgs = entry->next;
988 			_remove = entry;
989 		} else {
990 			_remove = NULL;
991 			prev = entry;
992 		}
993 		entry = entry->next;
994 
995 		if (_remove)
996 			radius_client_msg_free(_remove);
997 	}
998 
999 	return id;
1000 }
1001 
1002 
1003 /**
1004  * radius_client_flush - Flush all pending RADIUS client messages
1005  * @radius: RADIUS client context from radius_client_init()
1006  * @only_auth: Whether only authentication messages are removed
1007  */
1008 void radius_client_flush(struct radius_client_data *radius, int only_auth)
1009 {
1010 	struct radius_msg_list *entry, *prev, *tmp;
1011 
1012 	if (!radius)
1013 		return;
1014 
1015 	prev = NULL;
1016 	entry = radius->msgs;
1017 
1018 	while (entry) {
1019 		if (!only_auth || entry->msg_type == RADIUS_AUTH) {
1020 			if (prev)
1021 				prev->next = entry->next;
1022 			else
1023 				radius->msgs = entry->next;
1024 
1025 			tmp = entry;
1026 			entry = entry->next;
1027 			radius_client_msg_free(tmp);
1028 			radius->num_msgs--;
1029 		} else {
1030 			prev = entry;
1031 			entry = entry->next;
1032 		}
1033 	}
1034 
1035 	if (radius->msgs == NULL)
1036 		eloop_cancel_timeout(radius_client_timer, radius, NULL);
1037 }
1038 
1039 
1040 static void radius_client_update_acct_msgs(struct radius_client_data *radius,
1041 					   const u8 *shared_secret,
1042 					   size_t shared_secret_len)
1043 {
1044 	struct radius_msg_list *entry;
1045 
1046 	if (!radius)
1047 		return;
1048 
1049 	for (entry = radius->msgs; entry; entry = entry->next) {
1050 		if (entry->msg_type == RADIUS_ACCT) {
1051 			entry->shared_secret = shared_secret;
1052 			entry->shared_secret_len = shared_secret_len;
1053 			radius_msg_finish_acct(entry->msg, shared_secret,
1054 					       shared_secret_len);
1055 		}
1056 	}
1057 }
1058 
1059 
1060 static int
1061 radius_change_server(struct radius_client_data *radius,
1062 		     struct hostapd_radius_server *nserv,
1063 		     struct hostapd_radius_server *oserv,
1064 		     int sock, int sock6, int auth)
1065 {
1066 	struct sockaddr_in serv, claddr;
1067 #ifdef CONFIG_IPV6
1068 	struct sockaddr_in6 serv6, claddr6;
1069 #endif /* CONFIG_IPV6 */
1070 	struct sockaddr *addr, *cl_addr;
1071 	socklen_t addrlen, claddrlen;
1072 	char abuf[50];
1073 	int sel_sock;
1074 	struct radius_msg_list *entry;
1075 	struct hostapd_radius_servers *conf = radius->conf;
1076 	struct sockaddr_in disconnect_addr = {
1077 		.sin_family = AF_UNSPEC,
1078 	};
1079 
1080 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
1081 		       HOSTAPD_LEVEL_INFO,
1082 		       "%s server %s:%d",
1083 		       auth ? "Authentication" : "Accounting",
1084 		       hostapd_ip_txt(&nserv->addr, abuf, sizeof(abuf)),
1085 		       nserv->port);
1086 
1087 	if (oserv && oserv == nserv) {
1088 		/* Reconnect to same server, flush */
1089 		if (auth)
1090 			radius_client_flush(radius, 1);
1091 	}
1092 
1093 	if (oserv && oserv != nserv &&
1094 	    (nserv->shared_secret_len != oserv->shared_secret_len ||
1095 	     os_memcmp(nserv->shared_secret, oserv->shared_secret,
1096 		       nserv->shared_secret_len) != 0)) {
1097 		/* Pending RADIUS packets used different shared secret, so
1098 		 * they need to be modified. Update accounting message
1099 		 * authenticators here. Authentication messages are removed
1100 		 * since they would require more changes and the new RADIUS
1101 		 * server may not be prepared to receive them anyway due to
1102 		 * missing state information. Client will likely retry
1103 		 * authentication, so this should not be an issue. */
1104 		if (auth)
1105 			radius_client_flush(radius, 1);
1106 		else {
1107 			radius_client_update_acct_msgs(
1108 				radius, nserv->shared_secret,
1109 				nserv->shared_secret_len);
1110 		}
1111 	}
1112 
1113 	/* Reset retry counters */
1114 	for (entry = radius->msgs; oserv && entry; entry = entry->next) {
1115 		if ((auth && entry->msg_type != RADIUS_AUTH) ||
1116 		    (!auth && entry->msg_type != RADIUS_ACCT))
1117 			continue;
1118 		entry->next_try = entry->first_try + RADIUS_CLIENT_FIRST_WAIT;
1119 		entry->attempts = 1;
1120 		entry->next_wait = RADIUS_CLIENT_FIRST_WAIT * 2;
1121 	}
1122 
1123 	if (radius->msgs) {
1124 		eloop_cancel_timeout(radius_client_timer, radius, NULL);
1125 		eloop_register_timeout(RADIUS_CLIENT_FIRST_WAIT, 0,
1126 				       radius_client_timer, radius, NULL);
1127 	}
1128 
1129 	switch (nserv->addr.af) {
1130 	case AF_INET:
1131 		os_memset(&serv, 0, sizeof(serv));
1132 		serv.sin_family = AF_INET;
1133 		serv.sin_addr.s_addr = nserv->addr.u.v4.s_addr;
1134 		serv.sin_port = htons(nserv->port);
1135 		addr = (struct sockaddr *) &serv;
1136 		addrlen = sizeof(serv);
1137 		sel_sock = sock;
1138 		break;
1139 #ifdef CONFIG_IPV6
1140 	case AF_INET6:
1141 		os_memset(&serv6, 0, sizeof(serv6));
1142 		serv6.sin6_family = AF_INET6;
1143 		os_memcpy(&serv6.sin6_addr, &nserv->addr.u.v6,
1144 			  sizeof(struct in6_addr));
1145 		serv6.sin6_port = htons(nserv->port);
1146 		addr = (struct sockaddr *) &serv6;
1147 		addrlen = sizeof(serv6);
1148 		sel_sock = sock6;
1149 		break;
1150 #endif /* CONFIG_IPV6 */
1151 	default:
1152 		return -1;
1153 	}
1154 
1155 	if (sel_sock < 0) {
1156 		wpa_printf(MSG_INFO,
1157 			   "RADIUS: No server socket available (af=%d sock=%d sock6=%d auth=%d",
1158 			   nserv->addr.af, sock, sock6, auth);
1159 		return -1;
1160 	}
1161 
1162 	if (conf->force_client_addr) {
1163 		switch (conf->client_addr.af) {
1164 		case AF_INET:
1165 			os_memset(&claddr, 0, sizeof(claddr));
1166 			claddr.sin_family = AF_INET;
1167 			claddr.sin_addr.s_addr = conf->client_addr.u.v4.s_addr;
1168 			claddr.sin_port = htons(0);
1169 			cl_addr = (struct sockaddr *) &claddr;
1170 			claddrlen = sizeof(claddr);
1171 			break;
1172 #ifdef CONFIG_IPV6
1173 		case AF_INET6:
1174 			os_memset(&claddr6, 0, sizeof(claddr6));
1175 			claddr6.sin6_family = AF_INET6;
1176 			os_memcpy(&claddr6.sin6_addr, &conf->client_addr.u.v6,
1177 				  sizeof(struct in6_addr));
1178 			claddr6.sin6_port = htons(0);
1179 			cl_addr = (struct sockaddr *) &claddr6;
1180 			claddrlen = sizeof(claddr6);
1181 			break;
1182 #endif /* CONFIG_IPV6 */
1183 		default:
1184 			return -1;
1185 		}
1186 
1187 		if (bind(sel_sock, cl_addr, claddrlen) < 0) {
1188 			wpa_printf(MSG_INFO, "bind[radius]: %s",
1189 				   strerror(errno));
1190 			return -1;
1191 		}
1192 	}
1193 
1194 	/* Force a reconnect by disconnecting the socket first */
1195 	if (connect(sel_sock, (struct sockaddr *) &disconnect_addr,
1196 		    sizeof(disconnect_addr)) < 0)
1197 		wpa_printf(MSG_INFO, "disconnect[radius]: %s", strerror(errno));
1198 
1199 	if (connect(sel_sock, addr, addrlen) < 0) {
1200 		wpa_printf(MSG_INFO, "connect[radius]: %s", strerror(errno));
1201 		return -1;
1202 	}
1203 
1204 #ifndef CONFIG_NATIVE_WINDOWS
1205 	switch (nserv->addr.af) {
1206 	case AF_INET:
1207 		claddrlen = sizeof(claddr);
1208 		if (getsockname(sel_sock, (struct sockaddr *) &claddr,
1209 				&claddrlen) == 0) {
1210 			wpa_printf(MSG_DEBUG, "RADIUS local address: %s:%u",
1211 				   inet_ntoa(claddr.sin_addr),
1212 				   ntohs(claddr.sin_port));
1213 		}
1214 		break;
1215 #ifdef CONFIG_IPV6
1216 	case AF_INET6: {
1217 		claddrlen = sizeof(claddr6);
1218 		if (getsockname(sel_sock, (struct sockaddr *) &claddr6,
1219 				&claddrlen) == 0) {
1220 			wpa_printf(MSG_DEBUG, "RADIUS local address: %s:%u",
1221 				   inet_ntop(AF_INET6, &claddr6.sin6_addr,
1222 					     abuf, sizeof(abuf)),
1223 				   ntohs(claddr6.sin6_port));
1224 		}
1225 		break;
1226 	}
1227 #endif /* CONFIG_IPV6 */
1228 	}
1229 #endif /* CONFIG_NATIVE_WINDOWS */
1230 
1231 	if (auth)
1232 		radius->auth_sock = sel_sock;
1233 	else
1234 		radius->acct_sock = sel_sock;
1235 
1236 	return 0;
1237 }
1238 
1239 
1240 static void radius_retry_primary_timer(void *eloop_ctx, void *timeout_ctx)
1241 {
1242 	struct radius_client_data *radius = eloop_ctx;
1243 	struct hostapd_radius_servers *conf = radius->conf;
1244 	struct hostapd_radius_server *oserv;
1245 
1246 	if (radius->auth_sock >= 0 && conf->auth_servers &&
1247 	    conf->auth_server != conf->auth_servers) {
1248 		oserv = conf->auth_server;
1249 		conf->auth_server = conf->auth_servers;
1250 		if (radius_change_server(radius, conf->auth_server, oserv,
1251 					 radius->auth_serv_sock,
1252 					 radius->auth_serv_sock6, 1) < 0) {
1253 			conf->auth_server = oserv;
1254 			radius_change_server(radius, oserv, conf->auth_server,
1255 					     radius->auth_serv_sock,
1256 					     radius->auth_serv_sock6, 1);
1257 		}
1258 	}
1259 
1260 	if (radius->acct_sock >= 0 && conf->acct_servers &&
1261 	    conf->acct_server != conf->acct_servers) {
1262 		oserv = conf->acct_server;
1263 		conf->acct_server = conf->acct_servers;
1264 		if (radius_change_server(radius, conf->acct_server, oserv,
1265 					 radius->acct_serv_sock,
1266 					 radius->acct_serv_sock6, 0) < 0) {
1267 			conf->acct_server = oserv;
1268 			radius_change_server(radius, oserv, conf->acct_server,
1269 					     radius->acct_serv_sock,
1270 					     radius->acct_serv_sock6, 0);
1271 		}
1272 	}
1273 
1274 	if (conf->retry_primary_interval)
1275 		eloop_register_timeout(conf->retry_primary_interval, 0,
1276 				       radius_retry_primary_timer, radius,
1277 				       NULL);
1278 }
1279 
1280 
1281 static int radius_client_disable_pmtu_discovery(int s)
1282 {
1283 	int r = -1;
1284 #if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
1285 	/* Turn off Path MTU discovery on IPv4/UDP sockets. */
1286 	int action = IP_PMTUDISC_DONT;
1287 	r = setsockopt(s, IPPROTO_IP, IP_MTU_DISCOVER, &action,
1288 		       sizeof(action));
1289 	if (r == -1)
1290 		wpa_printf(MSG_ERROR, "RADIUS: Failed to set IP_MTU_DISCOVER: %s",
1291 			   strerror(errno));
1292 #endif
1293 	return r;
1294 }
1295 
1296 
1297 static void radius_close_auth_sockets(struct radius_client_data *radius)
1298 {
1299 	radius->auth_sock = -1;
1300 
1301 	if (radius->auth_serv_sock >= 0) {
1302 		eloop_unregister_read_sock(radius->auth_serv_sock);
1303 		close(radius->auth_serv_sock);
1304 		radius->auth_serv_sock = -1;
1305 	}
1306 #ifdef CONFIG_IPV6
1307 	if (radius->auth_serv_sock6 >= 0) {
1308 		eloop_unregister_read_sock(radius->auth_serv_sock6);
1309 		close(radius->auth_serv_sock6);
1310 		radius->auth_serv_sock6 = -1;
1311 	}
1312 #endif /* CONFIG_IPV6 */
1313 }
1314 
1315 
1316 static void radius_close_acct_sockets(struct radius_client_data *radius)
1317 {
1318 	radius->acct_sock = -1;
1319 
1320 	if (radius->acct_serv_sock >= 0) {
1321 		eloop_unregister_read_sock(radius->acct_serv_sock);
1322 		close(radius->acct_serv_sock);
1323 		radius->acct_serv_sock = -1;
1324 	}
1325 #ifdef CONFIG_IPV6
1326 	if (radius->acct_serv_sock6 >= 0) {
1327 		eloop_unregister_read_sock(radius->acct_serv_sock6);
1328 		close(radius->acct_serv_sock6);
1329 		radius->acct_serv_sock6 = -1;
1330 	}
1331 #endif /* CONFIG_IPV6 */
1332 }
1333 
1334 
1335 static int radius_client_init_auth(struct radius_client_data *radius)
1336 {
1337 	struct hostapd_radius_servers *conf = radius->conf;
1338 	int ok = 0;
1339 
1340 	radius_close_auth_sockets(radius);
1341 
1342 	radius->auth_serv_sock = socket(PF_INET, SOCK_DGRAM, 0);
1343 	if (radius->auth_serv_sock < 0)
1344 		wpa_printf(MSG_INFO, "RADIUS: socket[PF_INET,SOCK_DGRAM]: %s",
1345 			   strerror(errno));
1346 	else {
1347 		radius_client_disable_pmtu_discovery(radius->auth_serv_sock);
1348 		ok++;
1349 	}
1350 
1351 #ifdef CONFIG_IPV6
1352 	radius->auth_serv_sock6 = socket(PF_INET6, SOCK_DGRAM, 0);
1353 	if (radius->auth_serv_sock6 < 0)
1354 		wpa_printf(MSG_INFO, "RADIUS: socket[PF_INET6,SOCK_DGRAM]: %s",
1355 			   strerror(errno));
1356 	else
1357 		ok++;
1358 #endif /* CONFIG_IPV6 */
1359 
1360 	if (ok == 0)
1361 		return -1;
1362 
1363 	radius_change_server(radius, conf->auth_server, NULL,
1364 			     radius->auth_serv_sock, radius->auth_serv_sock6,
1365 			     1);
1366 
1367 	if (radius->auth_serv_sock >= 0 &&
1368 	    eloop_register_read_sock(radius->auth_serv_sock,
1369 				     radius_client_receive, radius,
1370 				     (void *) RADIUS_AUTH)) {
1371 		wpa_printf(MSG_INFO, "RADIUS: Could not register read socket for authentication server");
1372 		radius_close_auth_sockets(radius);
1373 		return -1;
1374 	}
1375 
1376 #ifdef CONFIG_IPV6
1377 	if (radius->auth_serv_sock6 >= 0 &&
1378 	    eloop_register_read_sock(radius->auth_serv_sock6,
1379 				     radius_client_receive, radius,
1380 				     (void *) RADIUS_AUTH)) {
1381 		wpa_printf(MSG_INFO, "RADIUS: Could not register read socket for authentication server");
1382 		radius_close_auth_sockets(radius);
1383 		return -1;
1384 	}
1385 #endif /* CONFIG_IPV6 */
1386 
1387 	return 0;
1388 }
1389 
1390 
1391 static int radius_client_init_acct(struct radius_client_data *radius)
1392 {
1393 	struct hostapd_radius_servers *conf = radius->conf;
1394 	int ok = 0;
1395 
1396 	radius_close_acct_sockets(radius);
1397 
1398 	radius->acct_serv_sock = socket(PF_INET, SOCK_DGRAM, 0);
1399 	if (radius->acct_serv_sock < 0)
1400 		wpa_printf(MSG_INFO, "RADIUS: socket[PF_INET,SOCK_DGRAM]: %s",
1401 			   strerror(errno));
1402 	else {
1403 		radius_client_disable_pmtu_discovery(radius->acct_serv_sock);
1404 		ok++;
1405 	}
1406 
1407 #ifdef CONFIG_IPV6
1408 	radius->acct_serv_sock6 = socket(PF_INET6, SOCK_DGRAM, 0);
1409 	if (radius->acct_serv_sock6 < 0)
1410 		wpa_printf(MSG_INFO, "RADIUS: socket[PF_INET6,SOCK_DGRAM]: %s",
1411 			   strerror(errno));
1412 	else
1413 		ok++;
1414 #endif /* CONFIG_IPV6 */
1415 
1416 	if (ok == 0)
1417 		return -1;
1418 
1419 	radius_change_server(radius, conf->acct_server, NULL,
1420 			     radius->acct_serv_sock, radius->acct_serv_sock6,
1421 			     0);
1422 
1423 	if (radius->acct_serv_sock >= 0 &&
1424 	    eloop_register_read_sock(radius->acct_serv_sock,
1425 				     radius_client_receive, radius,
1426 				     (void *) RADIUS_ACCT)) {
1427 		wpa_printf(MSG_INFO, "RADIUS: Could not register read socket for accounting server");
1428 		radius_close_acct_sockets(radius);
1429 		return -1;
1430 	}
1431 
1432 #ifdef CONFIG_IPV6
1433 	if (radius->acct_serv_sock6 >= 0 &&
1434 	    eloop_register_read_sock(radius->acct_serv_sock6,
1435 				     radius_client_receive, radius,
1436 				     (void *) RADIUS_ACCT)) {
1437 		wpa_printf(MSG_INFO, "RADIUS: Could not register read socket for accounting server");
1438 		radius_close_acct_sockets(radius);
1439 		return -1;
1440 	}
1441 #endif /* CONFIG_IPV6 */
1442 
1443 	return 0;
1444 }
1445 
1446 
1447 /**
1448  * radius_client_init - Initialize RADIUS client
1449  * @ctx: Callback context to be used in hostapd_logger() calls
1450  * @conf: RADIUS client configuration (RADIUS servers)
1451  * Returns: Pointer to private RADIUS client context or %NULL on failure
1452  *
1453  * The caller is responsible for keeping the configuration data available for
1454  * the lifetime of the RADIUS client, i.e., until radius_client_deinit() is
1455  * called for the returned context pointer.
1456  */
1457 struct radius_client_data *
1458 radius_client_init(void *ctx, struct hostapd_radius_servers *conf)
1459 {
1460 	struct radius_client_data *radius;
1461 
1462 	radius = os_zalloc(sizeof(struct radius_client_data));
1463 	if (radius == NULL)
1464 		return NULL;
1465 
1466 	radius->ctx = ctx;
1467 	radius->conf = conf;
1468 	radius->auth_serv_sock = radius->acct_serv_sock =
1469 		radius->auth_serv_sock6 = radius->acct_serv_sock6 =
1470 		radius->auth_sock = radius->acct_sock = -1;
1471 
1472 	if (conf->auth_server && radius_client_init_auth(radius)) {
1473 		radius_client_deinit(radius);
1474 		return NULL;
1475 	}
1476 
1477 	if (conf->acct_server && radius_client_init_acct(radius)) {
1478 		radius_client_deinit(radius);
1479 		return NULL;
1480 	}
1481 
1482 	if (conf->retry_primary_interval)
1483 		eloop_register_timeout(conf->retry_primary_interval, 0,
1484 				       radius_retry_primary_timer, radius,
1485 				       NULL);
1486 
1487 	return radius;
1488 }
1489 
1490 
1491 /**
1492  * radius_client_deinit - Deinitialize RADIUS client
1493  * @radius: RADIUS client context from radius_client_init()
1494  */
1495 void radius_client_deinit(struct radius_client_data *radius)
1496 {
1497 	if (!radius)
1498 		return;
1499 
1500 	radius_close_auth_sockets(radius);
1501 	radius_close_acct_sockets(radius);
1502 
1503 	eloop_cancel_timeout(radius_retry_primary_timer, radius, NULL);
1504 
1505 	radius_client_flush(radius, 0);
1506 	os_free(radius->auth_handlers);
1507 	os_free(radius->acct_handlers);
1508 	os_free(radius);
1509 }
1510 
1511 
1512 /**
1513  * radius_client_flush_auth - Flush pending RADIUS messages for an address
1514  * @radius: RADIUS client context from radius_client_init()
1515  * @addr: MAC address of the related device
1516  *
1517  * This function can be used to remove pending RADIUS authentication messages
1518  * that are related to a specific device. The addr parameter is matched with
1519  * the one used in radius_client_send() call that was used to transmit the
1520  * authentication request.
1521  */
1522 void radius_client_flush_auth(struct radius_client_data *radius,
1523 			      const u8 *addr)
1524 {
1525 	struct radius_msg_list *entry, *prev, *tmp;
1526 
1527 	prev = NULL;
1528 	entry = radius->msgs;
1529 	while (entry) {
1530 		if (entry->msg_type == RADIUS_AUTH &&
1531 		    os_memcmp(entry->addr, addr, ETH_ALEN) == 0) {
1532 			hostapd_logger(radius->ctx, addr,
1533 				       HOSTAPD_MODULE_RADIUS,
1534 				       HOSTAPD_LEVEL_DEBUG,
1535 				       "Removing pending RADIUS authentication"
1536 				       " message for removed client");
1537 
1538 			if (prev)
1539 				prev->next = entry->next;
1540 			else
1541 				radius->msgs = entry->next;
1542 
1543 			tmp = entry;
1544 			entry = entry->next;
1545 			radius_client_msg_free(tmp);
1546 			radius->num_msgs--;
1547 			continue;
1548 		}
1549 
1550 		prev = entry;
1551 		entry = entry->next;
1552 	}
1553 }
1554 
1555 
1556 static int radius_client_dump_auth_server(char *buf, size_t buflen,
1557 					  struct hostapd_radius_server *serv,
1558 					  struct radius_client_data *cli)
1559 {
1560 	int pending = 0;
1561 	struct radius_msg_list *msg;
1562 	char abuf[50];
1563 
1564 	if (cli) {
1565 		for (msg = cli->msgs; msg; msg = msg->next) {
1566 			if (msg->msg_type == RADIUS_AUTH)
1567 				pending++;
1568 		}
1569 	}
1570 
1571 	return os_snprintf(buf, buflen,
1572 			   "radiusAuthServerIndex=%d\n"
1573 			   "radiusAuthServerAddress=%s\n"
1574 			   "radiusAuthClientServerPortNumber=%d\n"
1575 			   "radiusAuthClientRoundTripTime=%d\n"
1576 			   "radiusAuthClientAccessRequests=%u\n"
1577 			   "radiusAuthClientAccessRetransmissions=%u\n"
1578 			   "radiusAuthClientAccessAccepts=%u\n"
1579 			   "radiusAuthClientAccessRejects=%u\n"
1580 			   "radiusAuthClientAccessChallenges=%u\n"
1581 			   "radiusAuthClientMalformedAccessResponses=%u\n"
1582 			   "radiusAuthClientBadAuthenticators=%u\n"
1583 			   "radiusAuthClientPendingRequests=%u\n"
1584 			   "radiusAuthClientTimeouts=%u\n"
1585 			   "radiusAuthClientUnknownTypes=%u\n"
1586 			   "radiusAuthClientPacketsDropped=%u\n",
1587 			   serv->index,
1588 			   hostapd_ip_txt(&serv->addr, abuf, sizeof(abuf)),
1589 			   serv->port,
1590 			   serv->round_trip_time,
1591 			   serv->requests,
1592 			   serv->retransmissions,
1593 			   serv->access_accepts,
1594 			   serv->access_rejects,
1595 			   serv->access_challenges,
1596 			   serv->malformed_responses,
1597 			   serv->bad_authenticators,
1598 			   pending,
1599 			   serv->timeouts,
1600 			   serv->unknown_types,
1601 			   serv->packets_dropped);
1602 }
1603 
1604 
1605 static int radius_client_dump_acct_server(char *buf, size_t buflen,
1606 					  struct hostapd_radius_server *serv,
1607 					  struct radius_client_data *cli)
1608 {
1609 	int pending = 0;
1610 	struct radius_msg_list *msg;
1611 	char abuf[50];
1612 
1613 	if (cli) {
1614 		for (msg = cli->msgs; msg; msg = msg->next) {
1615 			if (msg->msg_type == RADIUS_ACCT ||
1616 			    msg->msg_type == RADIUS_ACCT_INTERIM)
1617 				pending++;
1618 		}
1619 	}
1620 
1621 	return os_snprintf(buf, buflen,
1622 			   "radiusAccServerIndex=%d\n"
1623 			   "radiusAccServerAddress=%s\n"
1624 			   "radiusAccClientServerPortNumber=%d\n"
1625 			   "radiusAccClientRoundTripTime=%d\n"
1626 			   "radiusAccClientRequests=%u\n"
1627 			   "radiusAccClientRetransmissions=%u\n"
1628 			   "radiusAccClientResponses=%u\n"
1629 			   "radiusAccClientMalformedResponses=%u\n"
1630 			   "radiusAccClientBadAuthenticators=%u\n"
1631 			   "radiusAccClientPendingRequests=%u\n"
1632 			   "radiusAccClientTimeouts=%u\n"
1633 			   "radiusAccClientUnknownTypes=%u\n"
1634 			   "radiusAccClientPacketsDropped=%u\n",
1635 			   serv->index,
1636 			   hostapd_ip_txt(&serv->addr, abuf, sizeof(abuf)),
1637 			   serv->port,
1638 			   serv->round_trip_time,
1639 			   serv->requests,
1640 			   serv->retransmissions,
1641 			   serv->responses,
1642 			   serv->malformed_responses,
1643 			   serv->bad_authenticators,
1644 			   pending,
1645 			   serv->timeouts,
1646 			   serv->unknown_types,
1647 			   serv->packets_dropped);
1648 }
1649 
1650 
1651 /**
1652  * radius_client_get_mib - Get RADIUS client MIB information
1653  * @radius: RADIUS client context from radius_client_init()
1654  * @buf: Buffer for returning MIB data in text format
1655  * @buflen: Maximum buf length in octets
1656  * Returns: Number of octets written into the buffer
1657  */
1658 int radius_client_get_mib(struct radius_client_data *radius, char *buf,
1659 			  size_t buflen)
1660 {
1661 	struct hostapd_radius_servers *conf;
1662 	int i;
1663 	struct hostapd_radius_server *serv;
1664 	int count = 0;
1665 
1666 	if (!radius)
1667 		return 0;
1668 
1669 	conf = radius->conf;
1670 
1671 	if (conf->auth_servers) {
1672 		for (i = 0; i < conf->num_auth_servers; i++) {
1673 			serv = &conf->auth_servers[i];
1674 			count += radius_client_dump_auth_server(
1675 				buf + count, buflen - count, serv,
1676 				serv == conf->auth_server ?
1677 				radius : NULL);
1678 		}
1679 	}
1680 
1681 	if (conf->acct_servers) {
1682 		for (i = 0; i < conf->num_acct_servers; i++) {
1683 			serv = &conf->acct_servers[i];
1684 			count += radius_client_dump_acct_server(
1685 				buf + count, buflen - count, serv,
1686 				serv == conf->acct_server ?
1687 				radius : NULL);
1688 		}
1689 	}
1690 
1691 	return count;
1692 }
1693 
1694 
1695 void radius_client_reconfig(struct radius_client_data *radius,
1696 			    struct hostapd_radius_servers *conf)
1697 {
1698 	if (radius)
1699 		radius->conf = conf;
1700 }
1701