xref: /freebsd/contrib/wpa/src/radius/radius_client.c (revision 87b759f0fa1f7554d50ce640c40138512bbded44)
1 /*
2  * RADIUS client
3  * Copyright (c) 2002-2024, 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 #include <fcntl.h>
11 #include <net/if.h>
12 
13 #include "common.h"
14 #include "eloop.h"
15 #include "crypto/tls.h"
16 #include "radius.h"
17 #include "radius_client.h"
18 
19 /* Defaults for RADIUS retransmit values (exponential backoff) */
20 
21 /**
22  * RADIUS_CLIENT_FIRST_WAIT - RADIUS client timeout for first retry in seconds
23  */
24 #define RADIUS_CLIENT_FIRST_WAIT 3
25 
26 /**
27  * RADIUS_CLIENT_MAX_WAIT - RADIUS client maximum retry timeout in seconds
28  */
29 #define RADIUS_CLIENT_MAX_WAIT 120
30 
31 /**
32  * RADIUS_CLIENT_MAX_FAILOVER - RADIUS client maximum retries
33  *
34  * Maximum number of server failovers before the entry is removed from
35  * retransmit list.
36  */
37 #define RADIUS_CLIENT_MAX_FAILOVER 3
38 
39 /**
40  * RADIUS_CLIENT_MAX_ENTRIES - RADIUS client maximum pending messages
41  *
42  * Maximum number of entries in retransmit list (oldest entries will be
43  * removed, if this limit is exceeded).
44  */
45 #define RADIUS_CLIENT_MAX_ENTRIES 30
46 
47 /**
48  * RADIUS_CLIENT_NUM_FAILOVER - RADIUS client failover point
49  *
50  * The number of failed retry attempts after which the RADIUS server will be
51  * changed (if one of more backup servers are configured).
52  */
53 #define RADIUS_CLIENT_NUM_FAILOVER 4
54 
55 
56 /**
57  * struct radius_rx_handler - RADIUS client RX handler
58  *
59  * This data structure is used internally inside the RADIUS client module to
60  * store registered RX handlers. These handlers are registered by calls to
61  * radius_client_register() and unregistered when the RADIUS client is
62  * deinitialized with a call to radius_client_deinit().
63  */
64 struct radius_rx_handler {
65 	/**
66 	 * handler - Received RADIUS message handler
67 	 */
68 	RadiusRxResult (*handler)(struct radius_msg *msg,
69 				  struct radius_msg *req,
70 				  const u8 *shared_secret,
71 				  size_t shared_secret_len,
72 				  void *data);
73 
74 	/**
75 	 * data - Context data for the handler
76 	 */
77 	void *data;
78 };
79 
80 
81 /**
82  * struct radius_msg_list - RADIUS client message retransmit list
83  *
84  * This data structure is used internally inside the RADIUS client module to
85  * store pending RADIUS requests that may still need to be retransmitted.
86  */
87 struct radius_msg_list {
88 	/**
89 	 * addr - STA/client address
90 	 *
91 	 * This is used to find RADIUS messages for the same STA.
92 	 */
93 	u8 addr[ETH_ALEN];
94 
95 	/**
96 	 * msg - RADIUS message
97 	 */
98 	struct radius_msg *msg;
99 
100 	/**
101 	 * msg_type - Message type
102 	 */
103 	RadiusType msg_type;
104 
105 	/**
106 	 * first_try - Time of the first transmission attempt
107 	 */
108 	os_time_t first_try;
109 
110 	/**
111 	 * next_try - Time for the next transmission attempt
112 	 */
113 	os_time_t next_try;
114 
115 	/**
116 	 * attempts - Number of transmission attempts for one server
117 	 */
118 	int attempts;
119 
120 	/**
121 	 * accu_attempts - Number of accumulated attempts
122 	 */
123 	int accu_attempts;
124 
125 	/**
126 	 * next_wait - Next retransmission wait time in seconds
127 	 */
128 	int next_wait;
129 
130 	/**
131 	 * last_attempt - Time of the last transmission attempt
132 	 */
133 	struct os_reltime last_attempt;
134 
135 	/**
136 	 * shared_secret - Shared secret with the target RADIUS server
137 	 */
138 	const u8 *shared_secret;
139 
140 	/**
141 	 * shared_secret_len - shared_secret length in octets
142 	 */
143 	size_t shared_secret_len;
144 
145 	/* TODO: server config with failover to backup server(s) */
146 
147 	/**
148 	 * next - Next message in the list
149 	 */
150 	struct radius_msg_list *next;
151 };
152 
153 
154 /**
155  * struct radius_client_data - Internal RADIUS client data
156  *
157  * This data structure is used internally inside the RADIUS client module.
158  * External users allocate this by calling radius_client_init() and free it by
159  * calling radius_client_deinit(). The pointer to this opaque data is used in
160  * calls to other functions as an identifier for the RADIUS client instance.
161  */
162 struct radius_client_data {
163 	/**
164 	 * ctx - Context pointer for hostapd_logger() callbacks
165 	 */
166 	void *ctx;
167 
168 	/**
169 	 * conf - RADIUS client configuration (list of RADIUS servers to use)
170 	 */
171 	struct hostapd_radius_servers *conf;
172 
173 	/**
174 	 * auth_sock - Currently used socket for RADIUS authentication server
175 	 */
176 	int auth_sock;
177 
178 	/**
179 	 * auth_tls - Whether current authentication connection uses TLS
180 	 */
181 	bool auth_tls;
182 
183 	/**
184 	 * auth_tls_ready - Whether authentication TLS is ready
185 	 */
186 	bool auth_tls_ready;
187 
188 	/**
189 	 * acct_sock - Currently used socket for RADIUS accounting server
190 	 */
191 	int acct_sock;
192 
193 	/**
194 	 * acct_tls - Whether current accounting connection uses TLS
195 	 */
196 	bool acct_tls;
197 
198 	/**
199 	 * acct_tls_ready - Whether accounting TLS is ready
200 	 */
201 	bool acct_tls_ready;
202 
203 	/**
204 	 * auth_handlers - Authentication message handlers
205 	 */
206 	struct radius_rx_handler *auth_handlers;
207 
208 	/**
209 	 * num_auth_handlers - Number of handlers in auth_handlers
210 	 */
211 	size_t num_auth_handlers;
212 
213 	/**
214 	 * acct_handlers - Accounting message handlers
215 	 */
216 	struct radius_rx_handler *acct_handlers;
217 
218 	/**
219 	 * num_acct_handlers - Number of handlers in acct_handlers
220 	 */
221 	size_t num_acct_handlers;
222 
223 	/**
224 	 * msgs - Pending outgoing RADIUS messages
225 	 */
226 	struct radius_msg_list *msgs;
227 
228 	/**
229 	 * num_msgs - Number of pending messages in the msgs list
230 	 */
231 	size_t num_msgs;
232 
233 	/**
234 	 * next_radius_identifier - Next RADIUS message identifier to use
235 	 */
236 	u8 next_radius_identifier;
237 
238 	/**
239 	 * interim_error_cb - Interim accounting error callback
240 	 */
241 	void (*interim_error_cb)(const u8 *addr, void *ctx);
242 
243 	/**
244 	 * interim_error_cb_ctx - interim_error_cb() context data
245 	 */
246 	void *interim_error_cb_ctx;
247 
248 #ifdef CONFIG_RADIUS_TLS
249 	void *tls_ctx;
250 	struct tls_connection *auth_tls_conn;
251 	struct tls_connection *acct_tls_conn;
252 #endif /* CONFIG_RADIUS_TLS */
253 };
254 
255 
256 static int
257 radius_change_server(struct radius_client_data *radius,
258 		     struct hostapd_radius_server *nserv,
259 		     struct hostapd_radius_server *oserv,
260 		     int auth);
261 static int radius_client_init_acct(struct radius_client_data *radius);
262 static int radius_client_init_auth(struct radius_client_data *radius);
263 static void radius_client_auth_failover(struct radius_client_data *radius);
264 static void radius_client_acct_failover(struct radius_client_data *radius);
265 
266 
267 static void radius_client_msg_free(struct radius_msg_list *req)
268 {
269 	radius_msg_free(req->msg);
270 	os_free(req);
271 }
272 
273 
274 /**
275  * radius_client_register - Register a RADIUS client RX handler
276  * @radius: RADIUS client context from radius_client_init()
277  * @msg_type: RADIUS client type (RADIUS_AUTH or RADIUS_ACCT)
278  * @handler: Handler for received RADIUS messages
279  * @data: Context pointer for handler callbacks
280  * Returns: 0 on success, -1 on failure
281  *
282  * This function is used to register a handler for processing received RADIUS
283  * authentication and accounting messages. The handler() callback function will
284  * be called whenever a RADIUS message is received from the active server.
285  *
286  * There can be multiple registered RADIUS message handlers. The handlers will
287  * be called in order until one of them indicates that it has processed or
288  * queued the message.
289  */
290 int radius_client_register(struct radius_client_data *radius,
291 			   RadiusType msg_type,
292 			   RadiusRxResult (*handler)(struct radius_msg *msg,
293 						     struct radius_msg *req,
294 						     const u8 *shared_secret,
295 						     size_t shared_secret_len,
296 						     void *data),
297 			   void *data)
298 {
299 	struct radius_rx_handler **handlers, *newh;
300 	size_t *num;
301 
302 	if (msg_type == RADIUS_ACCT) {
303 		handlers = &radius->acct_handlers;
304 		num = &radius->num_acct_handlers;
305 	} else {
306 		handlers = &radius->auth_handlers;
307 		num = &radius->num_auth_handlers;
308 	}
309 
310 	newh = os_realloc_array(*handlers, *num + 1,
311 				sizeof(struct radius_rx_handler));
312 	if (newh == NULL)
313 		return -1;
314 
315 	newh[*num].handler = handler;
316 	newh[*num].data = data;
317 	(*num)++;
318 	*handlers = newh;
319 
320 	return 0;
321 }
322 
323 
324 /**
325  * radius_client_set_interim_erro_cb - Register an interim acct error callback
326  * @radius: RADIUS client context from radius_client_init()
327  * @addr: Station address from the failed message
328  * @cb: Handler for interim accounting errors
329  * @ctx: Context pointer for handler callbacks
330  *
331  * This function is used to register a handler for processing failed
332  * transmission attempts of interim accounting update messages.
333  */
334 void radius_client_set_interim_error_cb(struct radius_client_data *radius,
335 					void (*cb)(const u8 *addr, void *ctx),
336 					void *ctx)
337 {
338 	radius->interim_error_cb = cb;
339 	radius->interim_error_cb_ctx = ctx;
340 }
341 
342 
343 /*
344  * Returns >0 if message queue was flushed (i.e., the message that triggered
345  * the error is not available anymore)
346  */
347 static int radius_client_handle_send_error(struct radius_client_data *radius,
348 					   int s, RadiusType msg_type)
349 {
350 #ifndef CONFIG_NATIVE_WINDOWS
351 	int _errno = errno;
352 	wpa_printf(MSG_INFO, "send[RADIUS,s=%d]: %s", s, strerror(errno));
353 	if (_errno == ENOTCONN || _errno == EDESTADDRREQ || _errno == EINVAL ||
354 	    _errno == EBADF || _errno == ENETUNREACH || _errno == EACCES) {
355 		hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
356 			       HOSTAPD_LEVEL_INFO,
357 			       "Send failed - maybe interface status changed -"
358 			       " try to connect again");
359 		if (msg_type == RADIUS_ACCT ||
360 		    msg_type == RADIUS_ACCT_INTERIM) {
361 			radius_client_init_acct(radius);
362 			return 0;
363 		} else {
364 			radius_client_init_auth(radius);
365 			return 1;
366 		}
367 	}
368 #endif /* CONFIG_NATIVE_WINDOWS */
369 
370 	return 0;
371 }
372 
373 
374 static int radius_client_retransmit(struct radius_client_data *radius,
375 				    struct radius_msg_list *entry,
376 				    os_time_t now)
377 {
378 	struct hostapd_radius_servers *conf = radius->conf;
379 	int s;
380 	struct wpabuf *buf;
381 	size_t prev_num_msgs;
382 	u8 *acct_delay_time;
383 	size_t acct_delay_time_len;
384 	int num_servers;
385 #ifdef CONFIG_RADIUS_TLS
386 	struct wpabuf *out = NULL;
387 	struct tls_connection *conn = NULL;
388 	bool acct = false;
389 #endif /* CONFIG_RADIUS_TLS */
390 
391 	if (entry->msg_type == RADIUS_ACCT ||
392 	    entry->msg_type == RADIUS_ACCT_INTERIM) {
393 #ifdef CONFIG_RADIUS_TLS
394 		acct = true;
395 		if (radius->acct_tls)
396 			conn = radius->acct_tls_conn;
397 #endif /* CONFIG_RADIUS_TLS */
398 		num_servers = conf->num_acct_servers;
399 		if (radius->acct_sock < 0)
400 			radius_client_init_acct(radius);
401 		if (radius->acct_sock < 0 && conf->num_acct_servers > 1) {
402 			prev_num_msgs = radius->num_msgs;
403 			radius_client_acct_failover(radius);
404 			if (prev_num_msgs != radius->num_msgs)
405 				return 0;
406 		}
407 		s = radius->acct_sock;
408 		if (entry->attempts == 0)
409 			conf->acct_server->requests++;
410 		else {
411 			conf->acct_server->timeouts++;
412 			conf->acct_server->retransmissions++;
413 		}
414 	} else {
415 #ifdef CONFIG_RADIUS_TLS
416 		if (radius->auth_tls)
417 			conn = radius->auth_tls_conn;
418 #endif /* CONFIG_RADIUS_TLS */
419 		num_servers = conf->num_auth_servers;
420 		if (radius->auth_sock < 0)
421 			radius_client_init_auth(radius);
422 		if (radius->auth_sock < 0 && conf->num_auth_servers > 1) {
423 			prev_num_msgs = radius->num_msgs;
424 			radius_client_auth_failover(radius);
425 			if (prev_num_msgs != radius->num_msgs)
426 				return 0;
427 		}
428 		s = radius->auth_sock;
429 		if (entry->attempts == 0)
430 			conf->auth_server->requests++;
431 		else {
432 			conf->auth_server->timeouts++;
433 			conf->auth_server->retransmissions++;
434 		}
435 	}
436 
437 	if (entry->msg_type == RADIUS_ACCT_INTERIM) {
438 		wpa_printf(MSG_DEBUG,
439 			   "RADIUS: Failed to transmit interim accounting update to "
440 			   MACSTR " - drop message and request a new update",
441 			   MAC2STR(entry->addr));
442 		if (radius->interim_error_cb)
443 			radius->interim_error_cb(entry->addr,
444 						 radius->interim_error_cb_ctx);
445 		return 1;
446 	}
447 
448 	if (s < 0) {
449 		wpa_printf(MSG_INFO,
450 			   "RADIUS: No valid socket for retransmission");
451 		return 1;
452 	}
453 
454 #ifdef CONFIG_RADIUS_TLS
455 	if ((acct && radius->acct_tls && !radius->acct_tls_ready) ||
456 	    (!acct && radius->auth_tls && !radius->auth_tls_ready)) {
457 		wpa_printf(MSG_DEBUG,
458 			   "RADIUS: TLS connection not yet ready for TX");
459 		goto not_ready;
460 	}
461 #endif /* CONFIG_RADIUS_TLS */
462 
463 	if (entry->msg_type == RADIUS_ACCT &&
464 	    radius_msg_get_attr_ptr(entry->msg, RADIUS_ATTR_ACCT_DELAY_TIME,
465 				    &acct_delay_time, &acct_delay_time_len,
466 				    NULL) == 0 &&
467 	    acct_delay_time_len == 4) {
468 		struct radius_hdr *hdr;
469 		u32 delay_time;
470 
471 		/*
472 		 * Need to assign a new identifier since attribute contents
473 		 * changes.
474 		 */
475 		hdr = radius_msg_get_hdr(entry->msg);
476 		hdr->identifier = radius_client_get_id(radius);
477 
478 		/* Update Acct-Delay-Time to show wait time in queue */
479 		delay_time = now - entry->first_try;
480 		WPA_PUT_BE32(acct_delay_time, delay_time);
481 
482 		wpa_printf(MSG_DEBUG,
483 			   "RADIUS: Updated Acct-Delay-Time to %u for retransmission",
484 			   delay_time);
485 		radius_msg_finish_acct(entry->msg, entry->shared_secret,
486 				       entry->shared_secret_len);
487 		if (radius->conf->msg_dumps)
488 			radius_msg_dump(entry->msg);
489 	}
490 
491 	/* retransmit; remove entry if too many attempts */
492 	if (entry->accu_attempts >= RADIUS_CLIENT_MAX_FAILOVER *
493 	    RADIUS_CLIENT_NUM_FAILOVER * num_servers) {
494 		wpa_printf(MSG_INFO,
495 			   "RADIUS: Removing un-ACKed message due to too many failed retransmit attempts");
496 		return 1;
497 	}
498 
499 	entry->attempts++;
500 	entry->accu_attempts++;
501 	hostapd_logger(radius->ctx, entry->addr, HOSTAPD_MODULE_RADIUS,
502 		       HOSTAPD_LEVEL_DEBUG, "Resending RADIUS message (id=%d)",
503 		       radius_msg_get_hdr(entry->msg)->identifier);
504 
505 	os_get_reltime(&entry->last_attempt);
506 	buf = radius_msg_get_buf(entry->msg);
507 #ifdef CONFIG_RADIUS_TLS
508 	if (conn) {
509 		out = tls_connection_encrypt(radius->tls_ctx, conn, buf);
510 		if (!out) {
511 			wpa_printf(MSG_INFO,
512 				   "RADIUS: Failed to encrypt RADIUS message (TLS)");
513 			return -1;
514 		}
515 		wpa_printf(MSG_DEBUG,
516 			   "RADIUS: TLS encryption of %zu bytes of plaintext to %zu bytes of ciphertext",
517 			   wpabuf_len(buf), wpabuf_len(out));
518 		buf = out;
519 	}
520 #endif /* CONFIG_RADIUS_TLS */
521 
522 	wpa_printf(MSG_DEBUG, "RADIUS: Send %zu bytes to the server",
523 		   wpabuf_len(buf));
524 	if (send(s, wpabuf_head(buf), wpabuf_len(buf), 0) < 0) {
525 		if (radius_client_handle_send_error(radius, s, entry->msg_type)
526 		    > 0) {
527 #ifdef CONFIG_RADIUS_TLS
528 			wpabuf_free(out);
529 #endif /* CONFIG_RADIUS_TLS */
530 			return 0;
531 		}
532 	}
533 #ifdef CONFIG_RADIUS_TLS
534 	wpabuf_free(out);
535 
536 not_ready:
537 #endif /* CONFIG_RADIUS_TLS */
538 
539 	entry->next_try = now + entry->next_wait;
540 	entry->next_wait *= 2;
541 	if (entry->next_wait > RADIUS_CLIENT_MAX_WAIT)
542 		entry->next_wait = RADIUS_CLIENT_MAX_WAIT;
543 
544 	return 0;
545 }
546 
547 
548 static void radius_client_timer(void *eloop_ctx, void *timeout_ctx)
549 {
550 	struct radius_client_data *radius = eloop_ctx;
551 	struct os_reltime now;
552 	os_time_t first;
553 	struct radius_msg_list *entry, *prev, *tmp;
554 	int auth_failover = 0, acct_failover = 0;
555 	size_t prev_num_msgs;
556 	int s;
557 
558 	entry = radius->msgs;
559 	if (!entry)
560 		return;
561 
562 	os_get_reltime(&now);
563 
564 	while (entry) {
565 		if (now.sec >= entry->next_try) {
566 			s = entry->msg_type == RADIUS_AUTH ? radius->auth_sock :
567 				radius->acct_sock;
568 			if (entry->attempts >= RADIUS_CLIENT_NUM_FAILOVER ||
569 			    (s < 0 && entry->attempts > 0)) {
570 				if (entry->msg_type == RADIUS_ACCT ||
571 				    entry->msg_type == RADIUS_ACCT_INTERIM)
572 					acct_failover++;
573 				else
574 					auth_failover++;
575 			}
576 		}
577 		entry = entry->next;
578 	}
579 
580 	if (auth_failover)
581 		radius_client_auth_failover(radius);
582 
583 	if (acct_failover)
584 		radius_client_acct_failover(radius);
585 
586 	entry = radius->msgs;
587 	first = 0;
588 
589 	prev = NULL;
590 	while (entry) {
591 		prev_num_msgs = radius->num_msgs;
592 		if (now.sec >= entry->next_try &&
593 		    radius_client_retransmit(radius, entry, now.sec)) {
594 			if (prev)
595 				prev->next = entry->next;
596 			else
597 				radius->msgs = entry->next;
598 
599 			tmp = entry;
600 			entry = entry->next;
601 			radius_client_msg_free(tmp);
602 			radius->num_msgs--;
603 			continue;
604 		}
605 
606 		if (prev_num_msgs != radius->num_msgs) {
607 			wpa_printf(MSG_DEBUG,
608 				   "RADIUS: Message removed from queue - restart from beginning");
609 			entry = radius->msgs;
610 			prev = NULL;
611 			continue;
612 		}
613 
614 		if (first == 0 || entry->next_try < first)
615 			first = entry->next_try;
616 
617 		prev = entry;
618 		entry = entry->next;
619 	}
620 
621 	if (radius->msgs) {
622 		if (first < now.sec)
623 			first = now.sec;
624 		eloop_cancel_timeout(radius_client_timer, radius, NULL);
625 		eloop_register_timeout(first - now.sec, 0,
626 				       radius_client_timer, radius, NULL);
627 		hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
628 			       HOSTAPD_LEVEL_DEBUG, "Next RADIUS client "
629 			       "retransmit in %ld seconds",
630 			       (long int) (first - now.sec));
631 	}
632 }
633 
634 
635 static void radius_client_auth_failover(struct radius_client_data *radius)
636 {
637 	struct hostapd_radius_servers *conf = radius->conf;
638 	struct hostapd_radius_server *next, *old;
639 	struct radius_msg_list *entry;
640 	char abuf[50];
641 
642 	old = conf->auth_server;
643 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
644 		       HOSTAPD_LEVEL_NOTICE,
645 		       "No response from Authentication server %s:%d - failover",
646 		       hostapd_ip_txt(&old->addr, abuf, sizeof(abuf)),
647 		       old->port);
648 
649 	for (entry = radius->msgs; entry; entry = entry->next) {
650 		if (entry->msg_type == RADIUS_AUTH)
651 			old->timeouts++;
652 	}
653 
654 	next = old + 1;
655 	if (next > &(conf->auth_servers[conf->num_auth_servers - 1]))
656 		next = conf->auth_servers;
657 	conf->auth_server = next;
658 	radius_change_server(radius, next, old, 1);
659 }
660 
661 
662 static void radius_client_acct_failover(struct radius_client_data *radius)
663 {
664 	struct hostapd_radius_servers *conf = radius->conf;
665 	struct hostapd_radius_server *next, *old;
666 	struct radius_msg_list *entry;
667 	char abuf[50];
668 
669 	old = conf->acct_server;
670 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
671 		       HOSTAPD_LEVEL_NOTICE,
672 		       "No response from Accounting server %s:%d - failover",
673 		       hostapd_ip_txt(&old->addr, abuf, sizeof(abuf)),
674 		       old->port);
675 
676 	for (entry = radius->msgs; entry; entry = entry->next) {
677 		if (entry->msg_type == RADIUS_ACCT ||
678 		    entry->msg_type == RADIUS_ACCT_INTERIM)
679 			old->timeouts++;
680 	}
681 
682 	next = old + 1;
683 	if (next > &conf->acct_servers[conf->num_acct_servers - 1])
684 		next = conf->acct_servers;
685 	conf->acct_server = next;
686 	radius_change_server(radius, next, old, 0);
687 }
688 
689 
690 static void radius_client_update_timeout(struct radius_client_data *radius)
691 {
692 	struct os_reltime now;
693 	os_time_t first;
694 	struct radius_msg_list *entry;
695 
696 	eloop_cancel_timeout(radius_client_timer, radius, NULL);
697 
698 	if (radius->msgs == NULL) {
699 		return;
700 	}
701 
702 	first = 0;
703 	for (entry = radius->msgs; entry; entry = entry->next) {
704 		if (first == 0 || entry->next_try < first)
705 			first = entry->next_try;
706 	}
707 
708 	os_get_reltime(&now);
709 	if (first < now.sec)
710 		first = now.sec;
711 	eloop_register_timeout(first - now.sec, 0, radius_client_timer, radius,
712 			       NULL);
713 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
714 		       HOSTAPD_LEVEL_DEBUG, "Next RADIUS client retransmit in"
715 		       " %ld seconds", (long int) (first - now.sec));
716 }
717 
718 
719 static void radius_client_list_add(struct radius_client_data *radius,
720 				   struct radius_msg *msg,
721 				   RadiusType msg_type,
722 				   const u8 *shared_secret,
723 				   size_t shared_secret_len, const u8 *addr)
724 {
725 	struct radius_msg_list *entry, *prev;
726 
727 	if (eloop_terminated()) {
728 		/* No point in adding entries to retransmit queue since event
729 		 * loop has already been terminated. */
730 		radius_msg_free(msg);
731 		return;
732 	}
733 
734 	entry = os_zalloc(sizeof(*entry));
735 	if (entry == NULL) {
736 		wpa_printf(MSG_INFO, "RADIUS: Failed to add packet into retransmit list");
737 		radius_msg_free(msg);
738 		return;
739 	}
740 
741 	if (addr)
742 		os_memcpy(entry->addr, addr, ETH_ALEN);
743 	entry->msg = msg;
744 	entry->msg_type = msg_type;
745 	entry->shared_secret = shared_secret;
746 	entry->shared_secret_len = shared_secret_len;
747 	os_get_reltime(&entry->last_attempt);
748 	entry->first_try = entry->last_attempt.sec;
749 	entry->next_try = entry->first_try + RADIUS_CLIENT_FIRST_WAIT;
750 	entry->attempts = 1;
751 	entry->accu_attempts = 1;
752 	entry->next_wait = RADIUS_CLIENT_FIRST_WAIT * 2;
753 	if (entry->next_wait > RADIUS_CLIENT_MAX_WAIT)
754 		entry->next_wait = RADIUS_CLIENT_MAX_WAIT;
755 	entry->next = radius->msgs;
756 	radius->msgs = entry;
757 	radius_client_update_timeout(radius);
758 
759 	if (radius->num_msgs >= RADIUS_CLIENT_MAX_ENTRIES) {
760 		wpa_printf(MSG_INFO, "RADIUS: Removing the oldest un-ACKed packet due to retransmit list limits");
761 		prev = NULL;
762 		while (entry->next) {
763 			prev = entry;
764 			entry = entry->next;
765 		}
766 		if (prev) {
767 			prev->next = NULL;
768 			radius_client_msg_free(entry);
769 		}
770 	} else
771 		radius->num_msgs++;
772 }
773 
774 
775 static int radius_client_disable_pmtu_discovery(int s)
776 {
777 	int r = -1;
778 #if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
779 	/* Turn off Path MTU discovery on IPv4/UDP sockets. */
780 	int action = IP_PMTUDISC_DONT;
781 	r = setsockopt(s, IPPROTO_IP, IP_MTU_DISCOVER, &action,
782 		       sizeof(action));
783 	if (r == -1)
784 		wpa_printf(MSG_ERROR, "RADIUS: Failed to set IP_MTU_DISCOVER: %s",
785 			   strerror(errno));
786 #endif
787 	return r;
788 }
789 
790 
791 static void radius_close_auth_socket(struct radius_client_data *radius)
792 {
793 	if (radius->auth_sock >= 0) {
794 #ifdef CONFIG_RADIUS_TLS
795 		if (radius->conf->auth_server->tls)
796 			eloop_unregister_sock(radius->auth_sock,
797 					      EVENT_TYPE_WRITE);
798 #endif /* CONFIG_RADIUS_TLS */
799 		eloop_unregister_read_sock(radius->auth_sock);
800 		close(radius->auth_sock);
801 		radius->auth_sock = -1;
802 	}
803 }
804 
805 
806 static void radius_close_acct_socket(struct radius_client_data *radius)
807 {
808 	if (radius->acct_sock >= 0) {
809 #ifdef CONFIG_RADIUS_TLS
810 		if (radius->conf->acct_server->tls)
811 			eloop_unregister_sock(radius->acct_sock,
812 					      EVENT_TYPE_WRITE);
813 #endif /* CONFIG_RADIUS_TLS */
814 		eloop_unregister_read_sock(radius->acct_sock);
815 		close(radius->acct_sock);
816 		radius->acct_sock = -1;
817 	}
818 }
819 
820 
821 /**
822  * radius_client_send - Send a RADIUS request
823  * @radius: RADIUS client context from radius_client_init()
824  * @msg: RADIUS message to be sent
825  * @msg_type: Message type (RADIUS_AUTH, RADIUS_ACCT, RADIUS_ACCT_INTERIM)
826  * @addr: MAC address of the device related to this message or %NULL
827  * Returns: 0 on success, -1 on failure
828  *
829  * This function is used to transmit a RADIUS authentication (RADIUS_AUTH) or
830  * accounting request (RADIUS_ACCT or RADIUS_ACCT_INTERIM). The only difference
831  * between accounting and interim accounting messages is that the interim
832  * message will not be retransmitted. Instead, a callback is used to indicate
833  * that the transmission failed for the specific station @addr so that a new
834  * interim accounting update message can be generated with up-to-date session
835  * data instead of trying to resend old information.
836  *
837  * The message is added on the retransmission queue and will be retransmitted
838  * automatically until a response is received or maximum number of retries
839  * (RADIUS_CLIENT_MAX_FAILOVER * RADIUS_CLIENT_NUM_FAILOVER) is reached. No
840  * such retries are used with RADIUS_ACCT_INTERIM, i.e., such a pending message
841  * is removed from the queue automatically on transmission failure.
842  *
843  * The related device MAC address can be used to identify pending messages that
844  * can be removed with radius_client_flush_auth().
845  */
846 int radius_client_send(struct radius_client_data *radius,
847 		       struct radius_msg *msg, RadiusType msg_type,
848 		       const u8 *addr)
849 {
850 	struct hostapd_radius_servers *conf = radius->conf;
851 	const u8 *shared_secret;
852 	size_t shared_secret_len;
853 	char *name;
854 	int s, res;
855 	struct wpabuf *buf;
856 #ifdef CONFIG_RADIUS_TLS
857 	struct wpabuf *out = NULL;
858 	struct tls_connection *conn = NULL;
859 	bool acct = false;
860 #endif /* CONFIG_RADIUS_TLS */
861 
862 	if (msg_type == RADIUS_ACCT || msg_type == RADIUS_ACCT_INTERIM) {
863 #ifdef CONFIG_RADIUS_TLS
864 		acct = true;
865 		if (radius->acct_tls)
866 			conn = radius->acct_tls_conn;
867 #endif /* CONFIG_RADIUS_TLS */
868 		if (conf->acct_server && radius->acct_sock < 0)
869 			radius_client_init_acct(radius);
870 
871 		if (conf->acct_server == NULL || radius->acct_sock < 0 ||
872 		    conf->acct_server->shared_secret == NULL) {
873 			hostapd_logger(radius->ctx, NULL,
874 				       HOSTAPD_MODULE_RADIUS,
875 				       HOSTAPD_LEVEL_INFO,
876 				       "No accounting server configured");
877 			return -1;
878 		}
879 		shared_secret = conf->acct_server->shared_secret;
880 		shared_secret_len = conf->acct_server->shared_secret_len;
881 		radius_msg_finish_acct(msg, shared_secret, shared_secret_len);
882 		name = "accounting";
883 		s = radius->acct_sock;
884 		conf->acct_server->requests++;
885 	} else {
886 #ifdef CONFIG_RADIUS_TLS
887 		if (radius->auth_tls)
888 			conn = radius->auth_tls_conn;
889 #endif /* CONFIG_RADIUS_TLS */
890 		if (conf->auth_server && radius->auth_sock < 0)
891 			radius_client_init_auth(radius);
892 
893 		if (conf->auth_server == NULL || radius->auth_sock < 0 ||
894 		    conf->auth_server->shared_secret == NULL) {
895 			hostapd_logger(radius->ctx, NULL,
896 				       HOSTAPD_MODULE_RADIUS,
897 				       HOSTAPD_LEVEL_INFO,
898 				       "No authentication server configured");
899 			return -1;
900 		}
901 		shared_secret = conf->auth_server->shared_secret;
902 		shared_secret_len = conf->auth_server->shared_secret_len;
903 		radius_msg_finish(msg, shared_secret, shared_secret_len);
904 		name = "authentication";
905 		s = radius->auth_sock;
906 		conf->auth_server->requests++;
907 	}
908 
909 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
910 		       HOSTAPD_LEVEL_DEBUG, "Sending RADIUS message to %s "
911 		       "server", name);
912 	if (conf->msg_dumps)
913 		radius_msg_dump(msg);
914 
915 #ifdef CONFIG_RADIUS_TLS
916 	if ((acct && radius->acct_tls && !radius->acct_tls_ready) ||
917 	    (!acct && radius->auth_tls && !radius->auth_tls_ready)) {
918 		wpa_printf(MSG_DEBUG,
919 			   "RADIUS: TLS connection not yet ready for TX");
920 		goto skip_send;
921 	}
922 #endif /* CONFIG_RADIUS_TLS */
923 
924 	buf = radius_msg_get_buf(msg);
925 #ifdef CONFIG_RADIUS_TLS
926 	if (conn) {
927 		out = tls_connection_encrypt(radius->tls_ctx, conn, buf);
928 		if (!out) {
929 			wpa_printf(MSG_INFO,
930 				   "RADIUS: Failed to encrypt RADIUS message (TLS)");
931 			return -1;
932 		}
933 		wpa_printf(MSG_DEBUG,
934 			   "RADIUS: TLS encryption of %zu bytes of plaintext to %zu bytes of ciphertext",
935 			   wpabuf_len(buf), wpabuf_len(out));
936 		buf = out;
937 	}
938 #endif /* CONFIG_RADIUS_TLS */
939 	wpa_printf(MSG_DEBUG, "RADIUS: Send %zu bytes to the server",
940 		   wpabuf_len(buf));
941 	res = send(s, wpabuf_head(buf), wpabuf_len(buf), 0);
942 #ifdef CONFIG_RADIUS_TLS
943 	wpabuf_free(out);
944 #endif /* CONFIG_RADIUS_TLS */
945 	if (res < 0)
946 		radius_client_handle_send_error(radius, s, msg_type);
947 
948 #ifdef CONFIG_RADIUS_TLS
949 skip_send:
950 #endif /* CONFIG_RADIUS_TLS */
951 	radius_client_list_add(radius, msg, msg_type, shared_secret,
952 			       shared_secret_len, addr);
953 
954 	return 0;
955 }
956 
957 
958 #ifdef CONFIG_RADIUS_TLS
959 
960 static void radius_client_close_tcp(struct radius_client_data *radius,
961 				    int sock, RadiusType msg_type)
962 {
963 	wpa_printf(MSG_DEBUG, "RADIUS: Closing TCP connection (sock %d)",
964 		   sock);
965 	if (msg_type == RADIUS_ACCT) {
966 		radius->acct_tls_ready = false;
967 		radius_close_acct_socket(radius);
968 	} else {
969 		radius->auth_tls_ready = false;
970 		radius_close_auth_socket(radius);
971 	}
972 }
973 
974 
975 static void
976 radius_client_process_tls_handshake(struct radius_client_data *radius,
977 				    int sock, RadiusType msg_type,
978 				    u8 *buf, size_t len)
979 {
980 	struct wpabuf *in, *out = NULL, *appl;
981 	struct tls_connection *conn;
982 	int res;
983 	bool ready = false;
984 
985 	wpa_printf(MSG_DEBUG,
986 		   "RADIUS: Process %zu bytes of received TLS handshake message",
987 		   len);
988 
989 	if (msg_type == RADIUS_ACCT)
990 		conn = radius->acct_tls_conn;
991 	else
992 		conn = radius->auth_tls_conn;
993 
994 	in = wpabuf_alloc_copy(buf, len);
995 	if (!in)
996 		return;
997 
998 	appl = NULL;
999 	out = tls_connection_handshake(radius->tls_ctx, conn, in, &appl);
1000 	wpabuf_free(in);
1001 	if (!out) {
1002 		wpa_printf(MSG_DEBUG,
1003 			   "RADIUS: Could not generate TLS handshake data");
1004 		goto fail;
1005 	}
1006 
1007 	if (tls_connection_get_failed(radius->tls_ctx, conn)) {
1008 		wpa_printf(MSG_INFO, "RADIUS: TLS handshake failed");
1009 		goto fail;
1010 	}
1011 
1012 	if (tls_connection_established(radius->tls_ctx, conn)) {
1013 		wpa_printf(MSG_DEBUG,
1014 			   "RADIUS: TLS connection established (sock=%d)",
1015 			   sock);
1016 		if (msg_type == RADIUS_ACCT)
1017 			radius->acct_tls_ready = true;
1018 		else
1019 			radius->auth_tls_ready = true;
1020 		ready = true;
1021 	}
1022 
1023 	wpa_printf(MSG_DEBUG, "RADIUS: Sending %zu bytes of TLS handshake",
1024 		   wpabuf_len(out));
1025 	res = send(sock, wpabuf_head(out), wpabuf_len(out), 0);
1026 	if (res < 0) {
1027 		wpa_printf(MSG_INFO, "RADIUS: send: %s", strerror(errno));
1028 		goto fail;
1029 	}
1030 	if ((size_t) res != wpabuf_len(out)) {
1031 		wpa_printf(MSG_INFO,
1032 			   "RADIUS: Could not send all data for TLS handshake: only %d bytes sent",
1033 			   res);
1034 		goto fail;
1035 	}
1036 	wpabuf_free(out);
1037 
1038 	if (ready) {
1039 		struct radius_msg_list *entry, *prev, *tmp;
1040 		struct os_reltime now;
1041 
1042 		/* Send all pending message of matching type since the TLS
1043 		 * tunnel has now been established. */
1044 
1045 		os_get_reltime(&now);
1046 
1047 		entry = radius->msgs;
1048 		prev = NULL;
1049 		while (entry) {
1050 			if (entry->msg_type != msg_type) {
1051 				prev = entry;
1052 				entry = entry->next;
1053 				continue;
1054 			}
1055 
1056 			if (radius_client_retransmit(radius, entry, now.sec)) {
1057 				if (prev)
1058 					prev->next = entry->next;
1059 				else
1060 					radius->msgs = entry->next;
1061 
1062 				tmp = entry;
1063 				entry = entry->next;
1064 				radius_client_msg_free(tmp);
1065 				radius->num_msgs--;
1066 				continue;
1067 			}
1068 
1069 			prev = entry;
1070 			entry = entry->next;
1071 		}
1072 	}
1073 
1074 	return;
1075 
1076 fail:
1077 	wpabuf_free(out);
1078 	tls_connection_deinit(radius->tls_ctx, conn);
1079 	if (msg_type == RADIUS_ACCT)
1080 		radius->acct_tls_conn = NULL;
1081 	else
1082 		radius->auth_tls_conn = NULL;
1083 	radius_client_close_tcp(radius, sock, msg_type);
1084 }
1085 
1086 #endif /* CONFIG_RADIUS_TLS */
1087 
1088 
1089 static void radius_client_receive(int sock, void *eloop_ctx, void *sock_ctx)
1090 {
1091 	struct radius_client_data *radius = eloop_ctx;
1092 	struct hostapd_radius_servers *conf = radius->conf;
1093 	RadiusType msg_type = (uintptr_t) sock_ctx;
1094 	int len, roundtrip;
1095 	unsigned char buf[RADIUS_MAX_MSG_LEN];
1096 	struct msghdr msghdr = {0};
1097 	struct iovec iov;
1098 	struct radius_msg *msg;
1099 	struct radius_hdr *hdr;
1100 	struct radius_rx_handler *handlers;
1101 	size_t num_handlers, i;
1102 	struct radius_msg_list *req, *prev_req;
1103 	struct os_reltime now;
1104 	struct hostapd_radius_server *rconf;
1105 	int invalid_authenticator = 0;
1106 #ifdef CONFIG_RADIUS_TLS
1107 	struct tls_connection *conn = NULL;
1108 	bool tls, tls_ready;
1109 #endif /* CONFIG_RADIUS_TLS */
1110 
1111 	if (msg_type == RADIUS_ACCT) {
1112 #ifdef CONFIG_RADIUS_TLS
1113 		if (radius->acct_tls)
1114 			conn = radius->acct_tls_conn;
1115 		tls = radius->acct_tls;
1116 		tls_ready = radius->acct_tls_ready;
1117 #endif /* CONFIG_RADIUS_TLS */
1118 		handlers = radius->acct_handlers;
1119 		num_handlers = radius->num_acct_handlers;
1120 		rconf = conf->acct_server;
1121 	} else {
1122 #ifdef CONFIG_RADIUS_TLS
1123 		if (radius->auth_tls)
1124 			conn = radius->auth_tls_conn;
1125 		tls = radius->auth_tls;
1126 		tls_ready = radius->auth_tls_ready;
1127 #endif /* CONFIG_RADIUS_TLS */
1128 		handlers = radius->auth_handlers;
1129 		num_handlers = radius->num_auth_handlers;
1130 		rconf = conf->auth_server;
1131 	}
1132 
1133 	iov.iov_base = buf;
1134 	iov.iov_len = RADIUS_MAX_MSG_LEN;
1135 	msghdr.msg_iov = &iov;
1136 	msghdr.msg_iovlen = 1;
1137 	msghdr.msg_flags = 0;
1138 	len = recvmsg(sock, &msghdr, MSG_DONTWAIT);
1139 	if (len < 0) {
1140 		wpa_printf(MSG_INFO, "recvmsg[RADIUS]: %s", strerror(errno));
1141 		return;
1142 	}
1143 #ifdef CONFIG_RADIUS_TLS
1144 	if (tls && len == 0) {
1145 		wpa_printf(MSG_DEBUG, "RADIUS: No TCP data available");
1146 		goto close_tcp;
1147 	}
1148 
1149 	if (tls && !tls_ready) {
1150 		radius_client_process_tls_handshake(radius, sock, msg_type,
1151 						    buf, len);
1152 		return;
1153 	}
1154 
1155 	if (conn) {
1156 		struct wpabuf *out, *in;
1157 
1158 		in = wpabuf_alloc_copy(buf, len);
1159 		if (!in)
1160 			return;
1161 		wpa_printf(MSG_DEBUG,
1162 			   "RADIUS: Process %d bytes of encrypted TLS data",
1163 			   len);
1164 		out = tls_connection_decrypt(radius->tls_ctx, conn, in);
1165 		wpabuf_free(in);
1166 		if (!out) {
1167 			wpa_printf(MSG_INFO,
1168 				   "RADIUS: Failed to decrypt TLS data");
1169 			goto close_tcp;
1170 		}
1171 		if (wpabuf_len(out) == 0) {
1172 			wpa_printf(MSG_DEBUG,
1173 				   "RADIUS: Full message not yet received - continue waiting for additional TLS data");
1174 			wpabuf_free(out);
1175 			return;
1176 		}
1177 		if (wpabuf_len(out) > RADIUS_MAX_MSG_LEN) {
1178 			wpa_printf(MSG_INFO,
1179 				   "RADIUS: Too long RADIUS message from TLS: %zu",
1180 				   wpabuf_len(out));
1181 			wpabuf_free(out);
1182 			goto close_tcp;
1183 		}
1184 		os_memcpy(buf, wpabuf_head(out), wpabuf_len(out));
1185 		len = wpabuf_len(out);
1186 		wpabuf_free(out);
1187 	}
1188 #endif /* CONFIG_RADIUS_TLS */
1189 
1190 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
1191 		       HOSTAPD_LEVEL_DEBUG, "Received %d bytes from RADIUS "
1192 		       "server", len);
1193 
1194 	if (msghdr.msg_flags & MSG_TRUNC) {
1195 		wpa_printf(MSG_INFO, "RADIUS: Possibly too long UDP frame for our buffer - dropping it");
1196 		return;
1197 	}
1198 
1199 	msg = radius_msg_parse(buf, len);
1200 	if (msg == NULL) {
1201 		wpa_printf(MSG_INFO, "RADIUS: Parsing incoming frame failed");
1202 		rconf->malformed_responses++;
1203 		return;
1204 	}
1205 	hdr = radius_msg_get_hdr(msg);
1206 
1207 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
1208 		       HOSTAPD_LEVEL_DEBUG, "Received RADIUS message");
1209 	if (conf->msg_dumps)
1210 		radius_msg_dump(msg);
1211 
1212 	switch (hdr->code) {
1213 	case RADIUS_CODE_ACCESS_ACCEPT:
1214 		rconf->access_accepts++;
1215 		break;
1216 	case RADIUS_CODE_ACCESS_REJECT:
1217 		rconf->access_rejects++;
1218 		break;
1219 	case RADIUS_CODE_ACCESS_CHALLENGE:
1220 		rconf->access_challenges++;
1221 		break;
1222 	case RADIUS_CODE_ACCOUNTING_RESPONSE:
1223 		rconf->responses++;
1224 		break;
1225 	}
1226 
1227 	prev_req = NULL;
1228 	req = radius->msgs;
1229 	while (req) {
1230 		/* TODO: also match by src addr:port of the packet when using
1231 		 * alternative RADIUS servers (?) */
1232 		if ((req->msg_type == msg_type ||
1233 		     (req->msg_type == RADIUS_ACCT_INTERIM &&
1234 		      msg_type == RADIUS_ACCT)) &&
1235 		    radius_msg_get_hdr(req->msg)->identifier ==
1236 		    hdr->identifier)
1237 			break;
1238 
1239 		prev_req = req;
1240 		req = req->next;
1241 	}
1242 
1243 	if (req == NULL) {
1244 		hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
1245 			       HOSTAPD_LEVEL_DEBUG,
1246 			       "No matching RADIUS request found (type=%d "
1247 			       "id=%d) - dropping packet",
1248 			       msg_type, hdr->identifier);
1249 		goto fail;
1250 	}
1251 
1252 	os_get_reltime(&now);
1253 	roundtrip = (now.sec - req->last_attempt.sec) * 100 +
1254 		(now.usec - req->last_attempt.usec) / 10000;
1255 	hostapd_logger(radius->ctx, req->addr, HOSTAPD_MODULE_RADIUS,
1256 		       HOSTAPD_LEVEL_DEBUG,
1257 		       "Received RADIUS packet matched with a pending "
1258 		       "request, round trip time %d.%02d sec",
1259 		       roundtrip / 100, roundtrip % 100);
1260 	rconf->round_trip_time = roundtrip;
1261 
1262 	/* Remove ACKed RADIUS packet from retransmit list */
1263 	if (prev_req)
1264 		prev_req->next = req->next;
1265 	else
1266 		radius->msgs = req->next;
1267 	radius->num_msgs--;
1268 
1269 	for (i = 0; i < num_handlers; i++) {
1270 		RadiusRxResult res;
1271 		res = handlers[i].handler(msg, req->msg, req->shared_secret,
1272 					  req->shared_secret_len,
1273 					  handlers[i].data);
1274 		switch (res) {
1275 		case RADIUS_RX_PROCESSED:
1276 			radius_msg_free(msg);
1277 			/* fall through */
1278 		case RADIUS_RX_QUEUED:
1279 			radius_client_msg_free(req);
1280 			return;
1281 		case RADIUS_RX_INVALID_AUTHENTICATOR:
1282 			invalid_authenticator++;
1283 			/* fall through */
1284 		case RADIUS_RX_UNKNOWN:
1285 			/* continue with next handler */
1286 			break;
1287 		}
1288 	}
1289 
1290 	if (invalid_authenticator)
1291 		rconf->bad_authenticators++;
1292 	else
1293 		rconf->unknown_types++;
1294 	hostapd_logger(radius->ctx, req->addr, HOSTAPD_MODULE_RADIUS,
1295 		       HOSTAPD_LEVEL_DEBUG, "No RADIUS RX handler found "
1296 		       "(type=%d code=%d id=%d)%s - dropping packet",
1297 		       msg_type, hdr->code, hdr->identifier,
1298 		       invalid_authenticator ? " [INVALID AUTHENTICATOR]" :
1299 		       "");
1300 	radius_client_msg_free(req);
1301 
1302  fail:
1303 	radius_msg_free(msg);
1304 	return;
1305 
1306 #ifdef CONFIG_RADIUS_TLS
1307 close_tcp:
1308 	radius_client_close_tcp(radius, sock, msg_type);
1309 #endif /* CONFIG_RADIUS_TLS */
1310 }
1311 
1312 
1313 #ifdef CONFIG_RADIUS_TLS
1314 static void radius_client_write_ready(int sock, void *eloop_ctx, void *sock_ctx)
1315 {
1316 	struct radius_client_data *radius = eloop_ctx;
1317 	RadiusType msg_type = (uintptr_t) sock_ctx;
1318 	struct tls_connection *conn = NULL;
1319 	struct wpabuf *in, *out = NULL, *appl;
1320 	int res = -1;
1321 	struct tls_connection_params params;
1322 	struct hostapd_radius_server *server;
1323 
1324 	wpa_printf(MSG_DEBUG, "RADIUS: TCP connection established - start TLS handshake (sock=%d)",
1325 		   sock);
1326 
1327 	if (msg_type == RADIUS_ACCT) {
1328 		eloop_unregister_sock(sock, EVENT_TYPE_WRITE);
1329 		eloop_register_read_sock(sock, radius_client_receive, radius,
1330 					 (void *) RADIUS_ACCT);
1331 		if (radius->acct_tls_conn) {
1332 			wpa_printf(MSG_DEBUG,
1333 				   "RADIUS: Deinit previously used TLS connection");
1334 			tls_connection_deinit(radius->tls_ctx,
1335 					      radius->acct_tls_conn);
1336 			radius->acct_tls_conn = NULL;
1337 		}
1338 		server = radius->conf->acct_server;
1339 	} else {
1340 		eloop_unregister_sock(sock, EVENT_TYPE_WRITE);
1341 		eloop_register_read_sock(sock, radius_client_receive, radius,
1342 					 (void *) RADIUS_AUTH);
1343 		if (radius->auth_tls_conn) {
1344 			wpa_printf(MSG_DEBUG,
1345 				   "RADIUS: Deinit previously used TLS connection");
1346 			tls_connection_deinit(radius->tls_ctx,
1347 					      radius->auth_tls_conn);
1348 			radius->auth_tls_conn = NULL;
1349 		}
1350 		server = radius->conf->auth_server;
1351 	}
1352 
1353 	if (!server)
1354 		goto fail;
1355 
1356 	conn = tls_connection_init(radius->tls_ctx);
1357 	if (!conn) {
1358 		wpa_printf(MSG_INFO,
1359 			   "RADIUS: Failed to initiate TLS connection");
1360 		goto fail;
1361 	}
1362 
1363 	os_memset(&params, 0, sizeof(params));
1364 	params.ca_cert = server->ca_cert;
1365 	params.client_cert = server->client_cert;
1366 	params.private_key = server->private_key;
1367 	params.private_key_passwd = server->private_key_passwd;
1368 	params.flags = TLS_CONN_DISABLE_TLSv1_0 | TLS_CONN_DISABLE_TLSv1_1;
1369 	if (tls_connection_set_params(radius->tls_ctx, conn, &params)) {
1370 		wpa_printf(MSG_INFO,
1371 			   "RADIUS: Failed to set TLS connection parameters");
1372 		goto fail;
1373 	}
1374 
1375 	in = NULL;
1376 	appl = NULL;
1377 	out = tls_connection_handshake(radius->tls_ctx, conn, in, &appl);
1378 	if (!out) {
1379 		wpa_printf(MSG_DEBUG,
1380 			   "RADIUS: Could not generate TLS handshake data");
1381 		goto fail;
1382 	}
1383 
1384 	if (tls_connection_get_failed(radius->tls_ctx, conn)) {
1385 		wpa_printf(MSG_INFO, "RADIUS: TLS handshake failed");
1386 		goto fail;
1387 	}
1388 
1389 	wpa_printf(MSG_DEBUG, "RADIUS: Sending %zu bytes of TLS handshake",
1390 		   wpabuf_len(out));
1391 	res = send(sock, wpabuf_head(out), wpabuf_len(out), 0);
1392 	if (res < 0) {
1393 		wpa_printf(MSG_INFO, "RADIUS: send: %s", strerror(errno));
1394 		goto fail;
1395 	}
1396 	if ((size_t) res != wpabuf_len(out)) {
1397 		wpa_printf(MSG_INFO,
1398 			   "RADIUS: Could not send all data for TLS handshake: only %d bytes sent",
1399 			   res);
1400 		goto fail;
1401 	}
1402 	wpabuf_free(out);
1403 
1404 	if (msg_type == RADIUS_ACCT)
1405 		radius->acct_tls_conn = conn;
1406 	else
1407 		radius->auth_tls_conn = conn;
1408 	return;
1409 
1410 fail:
1411 	wpa_printf(MSG_INFO, "RADIUS: Failed to perform TLS handshake");
1412 	tls_connection_deinit(radius->tls_ctx, conn);
1413 	wpabuf_free(out);
1414 	radius_client_close_tcp(radius, sock, msg_type);
1415 }
1416 #endif /* CONFIG_RADIUS_TLS */
1417 
1418 
1419 /**
1420  * radius_client_get_id - Get an identifier for a new RADIUS message
1421  * @radius: RADIUS client context from radius_client_init()
1422  * Returns: Allocated identifier
1423  *
1424  * This function is used to fetch a unique (among pending requests) identifier
1425  * for a new RADIUS message.
1426  */
1427 u8 radius_client_get_id(struct radius_client_data *radius)
1428 {
1429 	struct radius_msg_list *entry, *prev, *_remove;
1430 	u8 id = radius->next_radius_identifier++;
1431 
1432 	/* remove entries with matching id from retransmit list to avoid
1433 	 * using new reply from the RADIUS server with an old request */
1434 	entry = radius->msgs;
1435 	prev = NULL;
1436 	while (entry) {
1437 		if (radius_msg_get_hdr(entry->msg)->identifier == id) {
1438 			hostapd_logger(radius->ctx, entry->addr,
1439 				       HOSTAPD_MODULE_RADIUS,
1440 				       HOSTAPD_LEVEL_DEBUG,
1441 				       "Removing pending RADIUS message, "
1442 				       "since its id (%d) is reused", id);
1443 			if (prev)
1444 				prev->next = entry->next;
1445 			else
1446 				radius->msgs = entry->next;
1447 			_remove = entry;
1448 		} else {
1449 			_remove = NULL;
1450 			prev = entry;
1451 		}
1452 		entry = entry->next;
1453 
1454 		if (_remove)
1455 			radius_client_msg_free(_remove);
1456 	}
1457 
1458 	return id;
1459 }
1460 
1461 
1462 /**
1463  * radius_client_flush - Flush all pending RADIUS client messages
1464  * @radius: RADIUS client context from radius_client_init()
1465  * @only_auth: Whether only authentication messages are removed
1466  */
1467 void radius_client_flush(struct radius_client_data *radius, int only_auth)
1468 {
1469 	struct radius_msg_list *entry, *prev, *tmp;
1470 
1471 	if (!radius)
1472 		return;
1473 
1474 	prev = NULL;
1475 	entry = radius->msgs;
1476 
1477 	while (entry) {
1478 		if (!only_auth || entry->msg_type == RADIUS_AUTH) {
1479 			if (prev)
1480 				prev->next = entry->next;
1481 			else
1482 				radius->msgs = entry->next;
1483 
1484 			tmp = entry;
1485 			entry = entry->next;
1486 			radius_client_msg_free(tmp);
1487 			radius->num_msgs--;
1488 		} else {
1489 			prev = entry;
1490 			entry = entry->next;
1491 		}
1492 	}
1493 
1494 	if (radius->msgs == NULL)
1495 		eloop_cancel_timeout(radius_client_timer, radius, NULL);
1496 }
1497 
1498 
1499 static void radius_client_update_acct_msgs(struct radius_client_data *radius,
1500 					   const u8 *shared_secret,
1501 					   size_t shared_secret_len)
1502 {
1503 	struct radius_msg_list *entry;
1504 
1505 	if (!radius)
1506 		return;
1507 
1508 	for (entry = radius->msgs; entry; entry = entry->next) {
1509 		if (entry->msg_type == RADIUS_ACCT) {
1510 			entry->shared_secret = shared_secret;
1511 			entry->shared_secret_len = shared_secret_len;
1512 			radius_msg_finish_acct(entry->msg, shared_secret,
1513 					       shared_secret_len);
1514 		}
1515 	}
1516 }
1517 
1518 
1519 static int
1520 radius_change_server(struct radius_client_data *radius,
1521 		     struct hostapd_radius_server *nserv,
1522 		     struct hostapd_radius_server *oserv,
1523 		     int auth)
1524 {
1525 	struct sockaddr_in serv, claddr;
1526 #ifdef CONFIG_IPV6
1527 	struct sockaddr_in6 serv6, claddr6;
1528 #endif /* CONFIG_IPV6 */
1529 	struct sockaddr *addr, *cl_addr;
1530 	socklen_t addrlen, claddrlen;
1531 	char abuf[50];
1532 	int sel_sock;
1533 	struct radius_msg_list *entry;
1534 	struct hostapd_radius_servers *conf = radius->conf;
1535 	int type = SOCK_DGRAM;
1536 	bool tls = nserv->tls;
1537 
1538 	if (tls) {
1539 #ifdef CONFIG_RADIUS_TLS
1540 		type = SOCK_STREAM;
1541 #else /* CONFIG_RADIUS_TLS */
1542 		wpa_printf(MSG_ERROR, "RADIUS: TLS not supported");
1543 		return -1;
1544 #endif /* CONFIG_RADIUS_TLS */
1545 	}
1546 
1547 	hostapd_logger(radius->ctx, NULL, HOSTAPD_MODULE_RADIUS,
1548 		       HOSTAPD_LEVEL_INFO,
1549 		       "%s server %s:%d",
1550 		       auth ? "Authentication" : "Accounting",
1551 		       hostapd_ip_txt(&nserv->addr, abuf, sizeof(abuf)),
1552 		       nserv->port);
1553 
1554 	if (oserv && oserv == nserv) {
1555 		/* Reconnect to same server, flush */
1556 		if (auth)
1557 			radius_client_flush(radius, 1);
1558 	}
1559 
1560 	if (oserv && oserv != nserv &&
1561 	    (nserv->shared_secret_len != oserv->shared_secret_len ||
1562 	     os_memcmp(nserv->shared_secret, oserv->shared_secret,
1563 		       nserv->shared_secret_len) != 0)) {
1564 		/* Pending RADIUS packets used different shared secret, so
1565 		 * they need to be modified. Update accounting message
1566 		 * authenticators here. Authentication messages are removed
1567 		 * since they would require more changes and the new RADIUS
1568 		 * server may not be prepared to receive them anyway due to
1569 		 * missing state information. Client will likely retry
1570 		 * authentication, so this should not be an issue. */
1571 		if (auth)
1572 			radius_client_flush(radius, 1);
1573 		else {
1574 			radius_client_update_acct_msgs(
1575 				radius, nserv->shared_secret,
1576 				nserv->shared_secret_len);
1577 		}
1578 	}
1579 
1580 	/* Reset retry counters */
1581 	for (entry = radius->msgs; oserv && entry; entry = entry->next) {
1582 		if ((auth && entry->msg_type != RADIUS_AUTH) ||
1583 		    (!auth && entry->msg_type != RADIUS_ACCT))
1584 			continue;
1585 		entry->next_try = entry->first_try + RADIUS_CLIENT_FIRST_WAIT;
1586 		entry->attempts = 0;
1587 		entry->next_wait = RADIUS_CLIENT_FIRST_WAIT * 2;
1588 	}
1589 
1590 	if (radius->msgs) {
1591 		eloop_cancel_timeout(radius_client_timer, radius, NULL);
1592 		eloop_register_timeout(RADIUS_CLIENT_FIRST_WAIT, 0,
1593 				       radius_client_timer, radius, NULL);
1594 	}
1595 
1596 	switch (nserv->addr.af) {
1597 	case AF_INET:
1598 		os_memset(&serv, 0, sizeof(serv));
1599 		serv.sin_family = AF_INET;
1600 		serv.sin_addr.s_addr = nserv->addr.u.v4.s_addr;
1601 		serv.sin_port = htons(nserv->port);
1602 		addr = (struct sockaddr *) &serv;
1603 		addrlen = sizeof(serv);
1604 		sel_sock = socket(PF_INET, type, 0);
1605 		if (sel_sock >= 0)
1606 			radius_client_disable_pmtu_discovery(sel_sock);
1607 		break;
1608 #ifdef CONFIG_IPV6
1609 	case AF_INET6:
1610 		os_memset(&serv6, 0, sizeof(serv6));
1611 		serv6.sin6_family = AF_INET6;
1612 		os_memcpy(&serv6.sin6_addr, &nserv->addr.u.v6,
1613 			  sizeof(struct in6_addr));
1614 		serv6.sin6_port = htons(nserv->port);
1615 		addr = (struct sockaddr *) &serv6;
1616 		addrlen = sizeof(serv6);
1617 		sel_sock = socket(PF_INET6, type, 0);
1618 		break;
1619 #endif /* CONFIG_IPV6 */
1620 	default:
1621 		return -1;
1622 	}
1623 
1624 	if (sel_sock < 0) {
1625 		wpa_printf(MSG_INFO,
1626 			   "RADIUS: Failed to open server socket (af=%d auth=%d)",
1627 			   nserv->addr.af, auth);
1628 		return -1;
1629 	}
1630 
1631 #ifdef CONFIG_RADIUS_TLS
1632 	if (tls && fcntl(sel_sock, F_SETFL, O_NONBLOCK) != 0) {
1633 		wpa_printf(MSG_DEBUG, "RADIUS: fnctl(O_NONBLOCK) failed: %s",
1634 			   strerror(errno));
1635 		close(sel_sock);
1636 		return -1;
1637 	}
1638 #endif /* CONFIG_RADIUS_TLS */
1639 
1640 #ifdef __linux__
1641 	if (conf->force_client_dev && conf->force_client_dev[0]) {
1642 		if (setsockopt(sel_sock, SOL_SOCKET, SO_BINDTODEVICE,
1643 			       conf->force_client_dev,
1644 			       os_strlen(conf->force_client_dev)) < 0) {
1645 			wpa_printf(MSG_ERROR,
1646 				   "RADIUS: setsockopt[SO_BINDTODEVICE]: %s",
1647 				   strerror(errno));
1648 			/* Probably not a critical error; continue on and hope
1649 			 * for the best. */
1650 		} else {
1651 			wpa_printf(MSG_DEBUG,
1652 				   "RADIUS: Bound client socket to device: %s",
1653 				   conf->force_client_dev);
1654 		}
1655 	}
1656 #endif /* __linux__ */
1657 
1658 	if (conf->force_client_addr) {
1659 		switch (conf->client_addr.af) {
1660 		case AF_INET:
1661 			os_memset(&claddr, 0, sizeof(claddr));
1662 			claddr.sin_family = AF_INET;
1663 			claddr.sin_addr.s_addr = conf->client_addr.u.v4.s_addr;
1664 			claddr.sin_port = htons(0);
1665 			cl_addr = (struct sockaddr *) &claddr;
1666 			claddrlen = sizeof(claddr);
1667 			break;
1668 #ifdef CONFIG_IPV6
1669 		case AF_INET6:
1670 			os_memset(&claddr6, 0, sizeof(claddr6));
1671 			claddr6.sin6_family = AF_INET6;
1672 			os_memcpy(&claddr6.sin6_addr, &conf->client_addr.u.v6,
1673 				  sizeof(struct in6_addr));
1674 			claddr6.sin6_port = htons(0);
1675 			cl_addr = (struct sockaddr *) &claddr6;
1676 			claddrlen = sizeof(claddr6);
1677 			break;
1678 #endif /* CONFIG_IPV6 */
1679 		default:
1680 			close(sel_sock);
1681 			return -1;
1682 		}
1683 
1684 		if (bind(sel_sock, cl_addr, claddrlen) < 0) {
1685 			wpa_printf(MSG_INFO, "bind[radius]: %s",
1686 				   strerror(errno));
1687 			close(sel_sock);
1688 			return -2;
1689 		}
1690 	}
1691 
1692 	if (connect(sel_sock, addr, addrlen) < 0) {
1693 		if (nserv->tls && errno == EINPROGRESS) {
1694 			wpa_printf(MSG_DEBUG,
1695 				   "RADIUS: TCP connection establishment in progress (sock %d)",
1696 				   sel_sock);
1697 		} else {
1698 			wpa_printf(MSG_INFO, "connect[radius]: %s",
1699 				   strerror(errno));
1700 			close(sel_sock);
1701 			return -2;
1702 		}
1703 	}
1704 
1705 #ifndef CONFIG_NATIVE_WINDOWS
1706 	switch (nserv->addr.af) {
1707 	case AF_INET:
1708 		claddrlen = sizeof(claddr);
1709 		if (getsockname(sel_sock, (struct sockaddr *) &claddr,
1710 				&claddrlen) == 0) {
1711 			wpa_printf(MSG_DEBUG, "RADIUS local address: %s:%u",
1712 				   inet_ntoa(claddr.sin_addr),
1713 				   ntohs(claddr.sin_port));
1714 		}
1715 		break;
1716 #ifdef CONFIG_IPV6
1717 	case AF_INET6: {
1718 		claddrlen = sizeof(claddr6);
1719 		if (getsockname(sel_sock, (struct sockaddr *) &claddr6,
1720 				&claddrlen) == 0) {
1721 			wpa_printf(MSG_DEBUG, "RADIUS local address: %s:%u",
1722 				   inet_ntop(AF_INET6, &claddr6.sin6_addr,
1723 					     abuf, sizeof(abuf)),
1724 				   ntohs(claddr6.sin6_port));
1725 		}
1726 		break;
1727 	}
1728 #endif /* CONFIG_IPV6 */
1729 	}
1730 #endif /* CONFIG_NATIVE_WINDOWS */
1731 
1732 	if (auth) {
1733 		radius_close_auth_socket(radius);
1734 		radius->auth_sock = sel_sock;
1735 	} else {
1736 		radius_close_acct_socket(radius);
1737 		radius->acct_sock = sel_sock;
1738 	}
1739 
1740 	if (!tls)
1741 		eloop_register_read_sock(sel_sock, radius_client_receive,
1742 					 radius,
1743 					 auth ? (void *) RADIUS_AUTH :
1744 					 (void *) RADIUS_ACCT);
1745 #ifdef CONFIG_RADIUS_TLS
1746 	if (tls)
1747 		eloop_register_sock(sel_sock, EVENT_TYPE_WRITE,
1748 				    radius_client_write_ready, radius,
1749 				    auth ? (void *) RADIUS_AUTH :
1750 				    (void *) RADIUS_ACCT);
1751 #endif /* CONFIG_RADIUS_TLS */
1752 
1753 	if (auth) {
1754 		radius->auth_tls = nserv->tls;
1755 		radius->auth_tls_ready = false;
1756 	} else {
1757 		radius->acct_tls = nserv->tls;
1758 		radius->acct_tls_ready = false;
1759 	}
1760 
1761 	return 0;
1762 }
1763 
1764 
1765 static void radius_retry_primary_timer(void *eloop_ctx, void *timeout_ctx)
1766 {
1767 	struct radius_client_data *radius = eloop_ctx;
1768 	struct hostapd_radius_servers *conf = radius->conf;
1769 	struct hostapd_radius_server *oserv;
1770 
1771 	if (radius->auth_sock >= 0 && conf->auth_servers &&
1772 	    conf->auth_server != conf->auth_servers) {
1773 		oserv = conf->auth_server;
1774 		conf->auth_server = conf->auth_servers;
1775 		if (radius_change_server(radius, conf->auth_server, oserv,
1776 					 1) < 0) {
1777 			conf->auth_server = oserv;
1778 			radius_change_server(radius, oserv, conf->auth_server,
1779 					     1);
1780 		}
1781 	}
1782 
1783 	if (radius->acct_sock >= 0 && conf->acct_servers &&
1784 	    conf->acct_server != conf->acct_servers) {
1785 		oserv = conf->acct_server;
1786 		conf->acct_server = conf->acct_servers;
1787 		if (radius_change_server(radius, conf->acct_server, oserv,
1788 					 0) < 0) {
1789 			conf->acct_server = oserv;
1790 			radius_change_server(radius, oserv, conf->acct_server,
1791 					     0);
1792 		}
1793 	}
1794 
1795 	if (conf->retry_primary_interval)
1796 		eloop_register_timeout(conf->retry_primary_interval, 0,
1797 				       radius_retry_primary_timer, radius,
1798 				       NULL);
1799 }
1800 
1801 
1802 static int radius_client_init_auth(struct radius_client_data *radius)
1803 {
1804 	radius_close_auth_socket(radius);
1805 	return radius_change_server(radius, radius->conf->auth_server, NULL, 1);
1806 }
1807 
1808 
1809 static int radius_client_init_acct(struct radius_client_data *radius)
1810 {
1811 	radius_close_acct_socket(radius);
1812 	return radius_change_server(radius, radius->conf->acct_server, NULL, 0);
1813 }
1814 
1815 
1816 #ifdef CONFIG_RADIUS_TLS
1817 static void radius_tls_event_cb(void *ctx, enum tls_event ev,
1818 				union tls_event_data *data)
1819 {
1820 	wpa_printf(MSG_DEBUG, "RADIUS: TLS event %d", ev);
1821 }
1822 #endif /* CONFIG_RADIUS_TLS */
1823 
1824 
1825 /**
1826  * radius_client_init - Initialize RADIUS client
1827  * @ctx: Callback context to be used in hostapd_logger() calls
1828  * @conf: RADIUS client configuration (RADIUS servers)
1829  * Returns: Pointer to private RADIUS client context or %NULL on failure
1830  *
1831  * The caller is responsible for keeping the configuration data available for
1832  * the lifetime of the RADIUS client, i.e., until radius_client_deinit() is
1833  * called for the returned context pointer.
1834  */
1835 struct radius_client_data *
1836 radius_client_init(void *ctx, struct hostapd_radius_servers *conf)
1837 {
1838 	struct radius_client_data *radius;
1839 
1840 	radius = os_zalloc(sizeof(struct radius_client_data));
1841 	if (radius == NULL)
1842 		return NULL;
1843 
1844 	radius->ctx = ctx;
1845 	radius->conf = conf;
1846 	radius->auth_sock = radius->acct_sock = -1;
1847 
1848 	if (conf->auth_server && radius_client_init_auth(radius) == -1) {
1849 		radius_client_deinit(radius);
1850 		return NULL;
1851 	}
1852 
1853 	if (conf->acct_server && radius_client_init_acct(radius) == -1) {
1854 		radius_client_deinit(radius);
1855 		return NULL;
1856 	}
1857 
1858 	if (conf->retry_primary_interval)
1859 		eloop_register_timeout(conf->retry_primary_interval, 0,
1860 				       radius_retry_primary_timer, radius,
1861 				       NULL);
1862 
1863 #ifdef CONFIG_RADIUS_TLS
1864 	if ((conf->auth_server && conf->auth_server->tls) ||
1865 	    (conf->acct_server && conf->acct_server->tls)) {
1866 		struct tls_config tls_conf;
1867 
1868 		os_memset(&tls_conf, 0, sizeof(tls_conf));
1869 		tls_conf.event_cb = radius_tls_event_cb;
1870 		radius->tls_ctx = tls_init(&tls_conf);
1871 		if (!radius->tls_ctx) {
1872 			radius_client_deinit(radius);
1873 			return NULL;
1874 		}
1875 	}
1876 #endif /* CONFIG_RADIUS_TLS */
1877 
1878 
1879 	return radius;
1880 }
1881 
1882 
1883 /**
1884  * radius_client_deinit - Deinitialize RADIUS client
1885  * @radius: RADIUS client context from radius_client_init()
1886  */
1887 void radius_client_deinit(struct radius_client_data *radius)
1888 {
1889 	if (!radius)
1890 		return;
1891 
1892 	radius_close_auth_socket(radius);
1893 	radius_close_acct_socket(radius);
1894 
1895 	eloop_cancel_timeout(radius_retry_primary_timer, radius, NULL);
1896 
1897 	radius_client_flush(radius, 0);
1898 	os_free(radius->auth_handlers);
1899 	os_free(radius->acct_handlers);
1900 #ifdef CONFIG_RADIUS_TLS
1901 	if (radius->tls_ctx) {
1902 		tls_connection_deinit(radius->tls_ctx, radius->auth_tls_conn);
1903 		tls_connection_deinit(radius->tls_ctx, radius->acct_tls_conn);
1904 		tls_deinit(radius->tls_ctx);
1905 	}
1906 #endif /* CONFIG_RADIUS_TLS */
1907 	os_free(radius);
1908 }
1909 
1910 
1911 /**
1912  * radius_client_flush_auth - Flush pending RADIUS messages for an address
1913  * @radius: RADIUS client context from radius_client_init()
1914  * @addr: MAC address of the related device
1915  *
1916  * This function can be used to remove pending RADIUS authentication messages
1917  * that are related to a specific device. The addr parameter is matched with
1918  * the one used in radius_client_send() call that was used to transmit the
1919  * authentication request.
1920  */
1921 void radius_client_flush_auth(struct radius_client_data *radius,
1922 			      const u8 *addr)
1923 {
1924 	struct radius_msg_list *entry, *prev, *tmp;
1925 
1926 	prev = NULL;
1927 	entry = radius->msgs;
1928 	while (entry) {
1929 		if (entry->msg_type == RADIUS_AUTH &&
1930 		    ether_addr_equal(entry->addr, addr)) {
1931 			hostapd_logger(radius->ctx, addr,
1932 				       HOSTAPD_MODULE_RADIUS,
1933 				       HOSTAPD_LEVEL_DEBUG,
1934 				       "Removing pending RADIUS authentication"
1935 				       " message for removed client");
1936 
1937 			if (prev)
1938 				prev->next = entry->next;
1939 			else
1940 				radius->msgs = entry->next;
1941 
1942 			tmp = entry;
1943 			entry = entry->next;
1944 			radius_client_msg_free(tmp);
1945 			radius->num_msgs--;
1946 			continue;
1947 		}
1948 
1949 		prev = entry;
1950 		entry = entry->next;
1951 	}
1952 }
1953 
1954 
1955 static int radius_client_dump_auth_server(char *buf, size_t buflen,
1956 					  struct hostapd_radius_server *serv,
1957 					  struct radius_client_data *cli)
1958 {
1959 	int pending = 0;
1960 	struct radius_msg_list *msg;
1961 	char abuf[50];
1962 
1963 	if (cli) {
1964 		for (msg = cli->msgs; msg; msg = msg->next) {
1965 			if (msg->msg_type == RADIUS_AUTH)
1966 				pending++;
1967 		}
1968 	}
1969 
1970 	return os_snprintf(buf, buflen,
1971 			   "radiusAuthServerIndex=%d\n"
1972 			   "radiusAuthServerAddress=%s\n"
1973 			   "radiusAuthClientServerPortNumber=%d\n"
1974 			   "radiusAuthClientRoundTripTime=%d\n"
1975 			   "radiusAuthClientAccessRequests=%u\n"
1976 			   "radiusAuthClientAccessRetransmissions=%u\n"
1977 			   "radiusAuthClientAccessAccepts=%u\n"
1978 			   "radiusAuthClientAccessRejects=%u\n"
1979 			   "radiusAuthClientAccessChallenges=%u\n"
1980 			   "radiusAuthClientMalformedAccessResponses=%u\n"
1981 			   "radiusAuthClientBadAuthenticators=%u\n"
1982 			   "radiusAuthClientPendingRequests=%u\n"
1983 			   "radiusAuthClientTimeouts=%u\n"
1984 			   "radiusAuthClientUnknownTypes=%u\n"
1985 			   "radiusAuthClientPacketsDropped=%u\n",
1986 			   serv->index,
1987 			   hostapd_ip_txt(&serv->addr, abuf, sizeof(abuf)),
1988 			   serv->port,
1989 			   serv->round_trip_time,
1990 			   serv->requests,
1991 			   serv->retransmissions,
1992 			   serv->access_accepts,
1993 			   serv->access_rejects,
1994 			   serv->access_challenges,
1995 			   serv->malformed_responses,
1996 			   serv->bad_authenticators,
1997 			   pending,
1998 			   serv->timeouts,
1999 			   serv->unknown_types,
2000 			   serv->packets_dropped);
2001 }
2002 
2003 
2004 static int radius_client_dump_acct_server(char *buf, size_t buflen,
2005 					  struct hostapd_radius_server *serv,
2006 					  struct radius_client_data *cli)
2007 {
2008 	int pending = 0;
2009 	struct radius_msg_list *msg;
2010 	char abuf[50];
2011 
2012 	if (cli) {
2013 		for (msg = cli->msgs; msg; msg = msg->next) {
2014 			if (msg->msg_type == RADIUS_ACCT ||
2015 			    msg->msg_type == RADIUS_ACCT_INTERIM)
2016 				pending++;
2017 		}
2018 	}
2019 
2020 	return os_snprintf(buf, buflen,
2021 			   "radiusAccServerIndex=%d\n"
2022 			   "radiusAccServerAddress=%s\n"
2023 			   "radiusAccClientServerPortNumber=%d\n"
2024 			   "radiusAccClientRoundTripTime=%d\n"
2025 			   "radiusAccClientRequests=%u\n"
2026 			   "radiusAccClientRetransmissions=%u\n"
2027 			   "radiusAccClientResponses=%u\n"
2028 			   "radiusAccClientMalformedResponses=%u\n"
2029 			   "radiusAccClientBadAuthenticators=%u\n"
2030 			   "radiusAccClientPendingRequests=%u\n"
2031 			   "radiusAccClientTimeouts=%u\n"
2032 			   "radiusAccClientUnknownTypes=%u\n"
2033 			   "radiusAccClientPacketsDropped=%u\n",
2034 			   serv->index,
2035 			   hostapd_ip_txt(&serv->addr, abuf, sizeof(abuf)),
2036 			   serv->port,
2037 			   serv->round_trip_time,
2038 			   serv->requests,
2039 			   serv->retransmissions,
2040 			   serv->responses,
2041 			   serv->malformed_responses,
2042 			   serv->bad_authenticators,
2043 			   pending,
2044 			   serv->timeouts,
2045 			   serv->unknown_types,
2046 			   serv->packets_dropped);
2047 }
2048 
2049 
2050 /**
2051  * radius_client_get_mib - Get RADIUS client MIB information
2052  * @radius: RADIUS client context from radius_client_init()
2053  * @buf: Buffer for returning MIB data in text format
2054  * @buflen: Maximum buf length in octets
2055  * Returns: Number of octets written into the buffer
2056  */
2057 int radius_client_get_mib(struct radius_client_data *radius, char *buf,
2058 			  size_t buflen)
2059 {
2060 	struct hostapd_radius_servers *conf;
2061 	int i;
2062 	struct hostapd_radius_server *serv;
2063 	int count = 0;
2064 
2065 	if (!radius)
2066 		return 0;
2067 
2068 	conf = radius->conf;
2069 
2070 	if (conf->auth_servers) {
2071 		for (i = 0; i < conf->num_auth_servers; i++) {
2072 			serv = &conf->auth_servers[i];
2073 			count += radius_client_dump_auth_server(
2074 				buf + count, buflen - count, serv,
2075 				serv == conf->auth_server ?
2076 				radius : NULL);
2077 		}
2078 	}
2079 
2080 	if (conf->acct_servers) {
2081 		for (i = 0; i < conf->num_acct_servers; i++) {
2082 			serv = &conf->acct_servers[i];
2083 			count += radius_client_dump_acct_server(
2084 				buf + count, buflen - count, serv,
2085 				serv == conf->acct_server ?
2086 				radius : NULL);
2087 		}
2088 	}
2089 
2090 	return count;
2091 }
2092 
2093 
2094 void radius_client_reconfig(struct radius_client_data *radius,
2095 			    struct hostapd_radius_servers *conf)
2096 {
2097 	if (radius)
2098 		radius->conf = conf;
2099 }
2100