1/*
2 * hostapd / EAP-AKA (RFC 4187) and EAP-AKA' (RFC 5448)
3 * Copyright (c) 2005-2012, 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 "crypto/sha256.h"
13#include "crypto/crypto.h"
14#include "crypto/random.h"
15#include "eap_common/eap_sim_common.h"
16#include "eap_server/eap_i.h"
17#include "eap_server/eap_sim_db.h"
18
19
20struct eap_aka_data {
21	u8 mk[EAP_SIM_MK_LEN];
22	u8 nonce_s[EAP_SIM_NONCE_S_LEN];
23	u8 k_aut[EAP_AKA_PRIME_K_AUT_LEN];
24	u8 k_encr[EAP_SIM_K_ENCR_LEN];
25	u8 k_re[EAP_AKA_PRIME_K_RE_LEN]; /* EAP-AKA' only */
26	u8 msk[EAP_SIM_KEYING_DATA_LEN];
27	u8 emsk[EAP_EMSK_LEN];
28	u8 rand[EAP_AKA_RAND_LEN];
29	u8 autn[EAP_AKA_AUTN_LEN];
30	u8 ck[EAP_AKA_CK_LEN];
31	u8 ik[EAP_AKA_IK_LEN];
32	u8 res[EAP_AKA_RES_MAX_LEN];
33	u8 reauth_mac[EAP_SIM_MAC_LEN];
34	size_t res_len;
35	enum {
36		IDENTITY, CHALLENGE, REAUTH, NOTIFICATION, SUCCESS, FAILURE
37	} state;
38	char *next_pseudonym;
39	char *next_reauth_id;
40	u16 counter;
41	struct eap_sim_reauth *reauth;
42	int auts_reported; /* whether the current AUTS has been reported to the
43			    * eap_sim_db */
44	u16 notification;
45	int use_result_ind;
46
47	struct wpabuf *id_msgs;
48	int pending_id;
49	u8 eap_method;
50	u8 *network_name;
51	size_t network_name_len;
52	u16 kdf;
53	int identity_round;
54	char permanent[20]; /* Permanent username */
55};
56
57
58static void eap_aka_fullauth(struct eap_sm *sm, struct eap_aka_data *data);
59
60
61static const char * eap_aka_state_txt(int state)
62{
63	switch (state) {
64	case IDENTITY:
65		return "IDENTITY";
66	case CHALLENGE:
67		return "CHALLENGE";
68	case REAUTH:
69		return "REAUTH";
70	case SUCCESS:
71		return "SUCCESS";
72	case FAILURE:
73		return "FAILURE";
74	case NOTIFICATION:
75		return "NOTIFICATION";
76	default:
77		return "Unknown?!";
78	}
79}
80
81
82static void eap_aka_state(struct eap_aka_data *data, int state)
83{
84	wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
85		   eap_aka_state_txt(data->state),
86		   eap_aka_state_txt(state));
87	data->state = state;
88}
89
90
91static int eap_aka_check_identity_reauth(struct eap_sm *sm,
92					 struct eap_aka_data *data,
93					 const char *username)
94{
95	if (data->eap_method == EAP_TYPE_AKA_PRIME &&
96	    username[0] != EAP_AKA_PRIME_REAUTH_ID_PREFIX)
97		return 0;
98	if (data->eap_method == EAP_TYPE_AKA &&
99	    username[0] != EAP_AKA_REAUTH_ID_PREFIX)
100		return 0;
101
102	wpa_printf(MSG_DEBUG, "EAP-AKA: Reauth username '%s'", username);
103	data->reauth = eap_sim_db_get_reauth_entry(sm->cfg->eap_sim_db_priv,
104						   username);
105	if (data->reauth == NULL) {
106		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown reauth identity - "
107			   "request full auth identity");
108		/* Remain in IDENTITY state for another round */
109		return 0;
110	}
111
112	wpa_printf(MSG_DEBUG, "EAP-AKA: Using fast re-authentication");
113	os_strlcpy(data->permanent, data->reauth->permanent,
114		   sizeof(data->permanent));
115	data->counter = data->reauth->counter;
116	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
117		os_memcpy(data->k_encr, data->reauth->k_encr,
118			  EAP_SIM_K_ENCR_LEN);
119		os_memcpy(data->k_aut, data->reauth->k_aut,
120			  EAP_AKA_PRIME_K_AUT_LEN);
121		os_memcpy(data->k_re, data->reauth->k_re,
122			  EAP_AKA_PRIME_K_RE_LEN);
123	} else {
124		os_memcpy(data->mk, data->reauth->mk, EAP_SIM_MK_LEN);
125	}
126
127	eap_aka_state(data, REAUTH);
128	return 1;
129}
130
131
132static void eap_aka_check_identity(struct eap_sm *sm,
133				   struct eap_aka_data *data)
134{
135	char *username;
136
137	/* Check if we already know the identity from EAP-Response/Identity */
138
139	username = sim_get_username(sm->identity, sm->identity_len);
140	if (username == NULL)
141		return;
142
143	if (eap_aka_check_identity_reauth(sm, data, username) > 0) {
144		os_free(username);
145		/*
146		 * Since re-auth username was recognized, skip AKA/Identity
147		 * exchange.
148		 */
149		return;
150	}
151
152	if ((data->eap_method == EAP_TYPE_AKA_PRIME &&
153	     username[0] == EAP_AKA_PRIME_PSEUDONYM_PREFIX) ||
154	    (data->eap_method == EAP_TYPE_AKA &&
155	     username[0] == EAP_AKA_PSEUDONYM_PREFIX)) {
156		const char *permanent;
157		wpa_printf(MSG_DEBUG, "EAP-AKA: Pseudonym username '%s'",
158			   username);
159		permanent = eap_sim_db_get_permanent(
160			sm->cfg->eap_sim_db_priv, username);
161		if (permanent == NULL) {
162			os_free(username);
163			wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown pseudonym "
164				   "identity - request permanent identity");
165			/* Remain in IDENTITY state for another round */
166			return;
167		}
168		os_strlcpy(data->permanent, permanent,
169			   sizeof(data->permanent));
170		/*
171		 * Since pseudonym username was recognized, skip AKA/Identity
172		 * exchange.
173		 */
174		eap_aka_fullauth(sm, data);
175	}
176
177	os_free(username);
178}
179
180
181static void * eap_aka_init(struct eap_sm *sm)
182{
183	struct eap_aka_data *data;
184
185	if (!sm->cfg->eap_sim_db_priv) {
186		wpa_printf(MSG_WARNING, "EAP-AKA: eap_sim_db not configured");
187		return NULL;
188	}
189
190	data = os_zalloc(sizeof(*data));
191	if (data == NULL)
192		return NULL;
193
194	data->eap_method = EAP_TYPE_AKA;
195
196	data->state = IDENTITY;
197	data->pending_id = -1;
198	eap_aka_check_identity(sm, data);
199
200	return data;
201}
202
203
204#ifdef EAP_SERVER_AKA_PRIME
205static void * eap_aka_prime_init(struct eap_sm *sm)
206{
207	struct eap_aka_data *data;
208	/* TODO: make ANID configurable; see 3GPP TS 24.302 */
209	char *network_name = "WLAN";
210
211	if (sm->cfg->eap_sim_db_priv == NULL) {
212		wpa_printf(MSG_WARNING, "EAP-AKA: eap_sim_db not configured");
213		return NULL;
214	}
215
216	data = os_zalloc(sizeof(*data));
217	if (data == NULL)
218		return NULL;
219
220	data->eap_method = EAP_TYPE_AKA_PRIME;
221	data->network_name = (u8 *) os_strdup(network_name);
222	if (data->network_name == NULL) {
223		os_free(data);
224		return NULL;
225	}
226
227	data->network_name_len = os_strlen(network_name);
228
229	data->state = IDENTITY;
230	data->pending_id = -1;
231	eap_aka_check_identity(sm, data);
232
233	return data;
234}
235#endif /* EAP_SERVER_AKA_PRIME */
236
237
238static void eap_aka_reset(struct eap_sm *sm, void *priv)
239{
240	struct eap_aka_data *data = priv;
241	os_free(data->next_pseudonym);
242	os_free(data->next_reauth_id);
243	wpabuf_free(data->id_msgs);
244	os_free(data->network_name);
245	bin_clear_free(data, sizeof(*data));
246}
247
248
249static int eap_aka_add_id_msg(struct eap_aka_data *data,
250			      const struct wpabuf *msg)
251{
252	if (msg == NULL)
253		return -1;
254
255	if (data->id_msgs == NULL) {
256		data->id_msgs = wpabuf_dup(msg);
257		return data->id_msgs == NULL ? -1 : 0;
258	}
259
260	if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
261		return -1;
262	wpabuf_put_buf(data->id_msgs, msg);
263
264	return 0;
265}
266
267
268static void eap_aka_add_checkcode(struct eap_aka_data *data,
269				  struct eap_sim_msg *msg)
270{
271	const u8 *addr;
272	size_t len;
273	u8 hash[SHA256_MAC_LEN];
274
275	wpa_printf(MSG_DEBUG, "   AT_CHECKCODE");
276
277	if (data->id_msgs == NULL) {
278		/*
279		 * No EAP-AKA/Identity packets were exchanged - send empty
280		 * checkcode.
281		 */
282		eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
283		return;
284	}
285
286	/* Checkcode is SHA1 hash over all EAP-AKA/Identity packets. */
287	addr = wpabuf_head(data->id_msgs);
288	len = wpabuf_len(data->id_msgs);
289	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
290	if (data->eap_method == EAP_TYPE_AKA_PRIME)
291		sha256_vector(1, &addr, &len, hash);
292	else
293		sha1_vector(1, &addr, &len, hash);
294
295	eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
296			data->eap_method == EAP_TYPE_AKA_PRIME ?
297			EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
298}
299
300
301static int eap_aka_verify_checkcode(struct eap_aka_data *data,
302				    const u8 *checkcode, size_t checkcode_len)
303{
304	const u8 *addr;
305	size_t len;
306	u8 hash[SHA256_MAC_LEN];
307	size_t hash_len;
308
309	if (checkcode == NULL)
310		return -1;
311
312	if (data->id_msgs == NULL) {
313		if (checkcode_len != 0) {
314			wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from peer "
315				   "indicates that AKA/Identity messages were "
316				   "used, but they were not");
317			return -1;
318		}
319		return 0;
320	}
321
322	hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
323		EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
324
325	if (checkcode_len != hash_len) {
326		wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from peer indicates "
327			   "that AKA/Identity message were not used, but they "
328			   "were");
329		return -1;
330	}
331
332	/* Checkcode is SHA1 hash over all EAP-AKA/Identity packets. */
333	addr = wpabuf_head(data->id_msgs);
334	len = wpabuf_len(data->id_msgs);
335	if (data->eap_method == EAP_TYPE_AKA_PRIME)
336		sha256_vector(1, &addr, &len, hash);
337	else
338		sha1_vector(1, &addr, &len, hash);
339
340	if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
341		wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
342		return -1;
343	}
344
345	return 0;
346}
347
348
349static struct wpabuf * eap_aka_build_identity(struct eap_sm *sm,
350					      struct eap_aka_data *data, u8 id)
351{
352	struct eap_sim_msg *msg;
353	struct wpabuf *buf;
354
355	wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Identity");
356	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
357			       EAP_AKA_SUBTYPE_IDENTITY);
358	data->identity_round++;
359	if (data->identity_round == 1) {
360		/*
361		 * RFC 4187, Chap. 4.1.4 recommends that identity from EAP is
362		 * ignored and the AKA/Identity is used to request the
363		 * identity.
364		 */
365		wpa_printf(MSG_DEBUG, "   AT_ANY_ID_REQ");
366		eap_sim_msg_add(msg, EAP_SIM_AT_ANY_ID_REQ, 0, NULL, 0);
367	} else if (data->identity_round > 3) {
368		/* Cannot use more than three rounds of Identity messages */
369		eap_sim_msg_free(msg);
370		return NULL;
371	} else if (sm->identity && sm->identity_len > 0 &&
372		   (sm->identity[0] == EAP_AKA_REAUTH_ID_PREFIX ||
373		    sm->identity[0] == EAP_AKA_PRIME_REAUTH_ID_PREFIX)) {
374		/* Reauth id may have expired - try fullauth */
375		wpa_printf(MSG_DEBUG, "   AT_FULLAUTH_ID_REQ");
376		eap_sim_msg_add(msg, EAP_SIM_AT_FULLAUTH_ID_REQ, 0, NULL, 0);
377	} else {
378		wpa_printf(MSG_DEBUG, "   AT_PERMANENT_ID_REQ");
379		eap_sim_msg_add(msg, EAP_SIM_AT_PERMANENT_ID_REQ, 0, NULL, 0);
380	}
381	buf = eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
382	if (eap_aka_add_id_msg(data, buf) < 0) {
383		wpabuf_free(buf);
384		return NULL;
385	}
386	data->pending_id = id;
387	return buf;
388}
389
390
391static int eap_aka_build_encr(struct eap_sm *sm, struct eap_aka_data *data,
392			      struct eap_sim_msg *msg, u16 counter,
393			      const u8 *nonce_s)
394{
395	os_free(data->next_pseudonym);
396	if (!(sm->cfg->eap_sim_id & 0x01)) {
397		/* Use of pseudonyms disabled in configuration */
398		data->next_pseudonym = NULL;
399	} else if (!nonce_s) {
400		data->next_pseudonym =
401			eap_sim_db_get_next_pseudonym(
402				sm->cfg->eap_sim_db_priv,
403				data->eap_method == EAP_TYPE_AKA_PRIME ?
404				EAP_SIM_DB_AKA_PRIME : EAP_SIM_DB_AKA);
405	} else {
406		/* Do not update pseudonym during re-authentication */
407		data->next_pseudonym = NULL;
408	}
409	os_free(data->next_reauth_id);
410	if (!(sm->cfg->eap_sim_id & 0x02)) {
411		/* Use of fast reauth disabled in configuration */
412		data->next_reauth_id = NULL;
413	} else if (data->counter <= EAP_AKA_MAX_FAST_REAUTHS) {
414		data->next_reauth_id =
415			eap_sim_db_get_next_reauth_id(
416				sm->cfg->eap_sim_db_priv,
417				data->eap_method == EAP_TYPE_AKA_PRIME ?
418				EAP_SIM_DB_AKA_PRIME : EAP_SIM_DB_AKA);
419	} else {
420		wpa_printf(MSG_DEBUG, "EAP-AKA: Max fast re-authentication "
421			   "count exceeded - force full authentication");
422		data->next_reauth_id = NULL;
423	}
424
425	if (data->next_pseudonym == NULL && data->next_reauth_id == NULL &&
426	    counter == 0 && nonce_s == NULL)
427		return 0;
428
429	wpa_printf(MSG_DEBUG, "   AT_IV");
430	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
431	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
432
433	if (counter > 0) {
434		wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)", counter);
435		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
436	}
437
438	if (nonce_s) {
439		wpa_printf(MSG_DEBUG, "   *AT_NONCE_S");
440		eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_S, 0, nonce_s,
441				EAP_SIM_NONCE_S_LEN);
442	}
443
444	if (data->next_pseudonym) {
445		wpa_printf(MSG_DEBUG, "   *AT_NEXT_PSEUDONYM (%s)",
446			   data->next_pseudonym);
447		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_PSEUDONYM,
448				os_strlen(data->next_pseudonym),
449				(u8 *) data->next_pseudonym,
450				os_strlen(data->next_pseudonym));
451	}
452
453	if (data->next_reauth_id) {
454		wpa_printf(MSG_DEBUG, "   *AT_NEXT_REAUTH_ID (%s)",
455			   data->next_reauth_id);
456		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_REAUTH_ID,
457				os_strlen(data->next_reauth_id),
458				(u8 *) data->next_reauth_id,
459				os_strlen(data->next_reauth_id));
460	}
461
462	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
463		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
464			   "AT_ENCR_DATA");
465		return -1;
466	}
467
468	return 0;
469}
470
471
472static struct wpabuf * eap_aka_build_challenge(struct eap_sm *sm,
473					       struct eap_aka_data *data,
474					       u8 id)
475{
476	struct eap_sim_msg *msg;
477
478	wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Challenge");
479	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
480			       EAP_AKA_SUBTYPE_CHALLENGE);
481	wpa_printf(MSG_DEBUG, "   AT_RAND");
482	eap_sim_msg_add(msg, EAP_SIM_AT_RAND, 0, data->rand, EAP_AKA_RAND_LEN);
483	wpa_printf(MSG_DEBUG, "   AT_AUTN");
484	eap_sim_msg_add(msg, EAP_SIM_AT_AUTN, 0, data->autn, EAP_AKA_AUTN_LEN);
485	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
486		if (data->kdf) {
487			/* Add the selected KDF into the beginning */
488			wpa_printf(MSG_DEBUG, "   AT_KDF");
489			eap_sim_msg_add(msg, EAP_SIM_AT_KDF, data->kdf,
490					NULL, 0);
491		}
492		wpa_printf(MSG_DEBUG, "   AT_KDF");
493		eap_sim_msg_add(msg, EAP_SIM_AT_KDF, EAP_AKA_PRIME_KDF,
494				NULL, 0);
495		wpa_printf(MSG_DEBUG, "   AT_KDF_INPUT");
496		eap_sim_msg_add(msg, EAP_SIM_AT_KDF_INPUT,
497				data->network_name_len,
498				data->network_name, data->network_name_len);
499	}
500
501	if (eap_aka_build_encr(sm, data, msg, 0, NULL)) {
502		eap_sim_msg_free(msg);
503		return NULL;
504	}
505
506	eap_aka_add_checkcode(data, msg);
507
508	if (sm->cfg->eap_sim_aka_result_ind) {
509		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
510		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
511	}
512
513#ifdef EAP_SERVER_AKA_PRIME
514	if (data->eap_method == EAP_TYPE_AKA) {
515		u16 flags = 0;
516		int i;
517		int aka_prime_preferred = 0;
518
519		i = 0;
520		while (sm->user && i < EAP_MAX_METHODS &&
521		       (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
522			sm->user->methods[i].method != EAP_TYPE_NONE)) {
523			if (sm->user->methods[i].vendor == EAP_VENDOR_IETF) {
524				if (sm->user->methods[i].method ==
525				    EAP_TYPE_AKA)
526					break;
527				if (sm->user->methods[i].method ==
528				    EAP_TYPE_AKA_PRIME) {
529					aka_prime_preferred = 1;
530					break;
531				}
532			}
533			i++;
534		}
535
536		if (aka_prime_preferred)
537			flags |= EAP_AKA_BIDDING_FLAG_D;
538		eap_sim_msg_add(msg, EAP_SIM_AT_BIDDING, flags, NULL, 0);
539	}
540#endif /* EAP_SERVER_AKA_PRIME */
541
542	wpa_printf(MSG_DEBUG, "   AT_MAC");
543	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
544	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, NULL, 0);
545}
546
547
548static struct wpabuf * eap_aka_build_reauth(struct eap_sm *sm,
549					    struct eap_aka_data *data, u8 id)
550{
551	struct eap_sim_msg *msg;
552	struct wpabuf *buf;
553
554	wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Re-authentication");
555
556	if (random_get_bytes(data->nonce_s, EAP_SIM_NONCE_S_LEN))
557		return NULL;
558	wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA: NONCE_S",
559			data->nonce_s, EAP_SIM_NONCE_S_LEN);
560
561	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
562		eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
563						 sm->identity,
564						 sm->identity_len,
565						 data->nonce_s,
566						 data->msk, data->emsk);
567	} else {
568		eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
569				    data->msk, data->emsk);
570		eap_sim_derive_keys_reauth(data->counter, sm->identity,
571					   sm->identity_len, data->nonce_s,
572					   data->mk, data->msk, data->emsk);
573	}
574
575	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
576			       EAP_AKA_SUBTYPE_REAUTHENTICATION);
577
578	if (eap_aka_build_encr(sm, data, msg, data->counter, data->nonce_s)) {
579		eap_sim_msg_free(msg);
580		return NULL;
581	}
582
583	eap_aka_add_checkcode(data, msg);
584
585	if (sm->cfg->eap_sim_aka_result_ind) {
586		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
587		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
588	}
589
590	wpa_printf(MSG_DEBUG, "   AT_MAC");
591	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
592	buf = eap_sim_msg_finish(msg, data->eap_method, data->k_aut, NULL, 0);
593
594	/* Remember this MAC before sending it to the peer. This MAC is used for
595	 * Session-Id calculation after receiving response from the peer and
596	 * after all other checks pass. */
597	os_memcpy(data->reauth_mac,
598		  wpabuf_head_u8(buf) + wpabuf_len(buf) - EAP_SIM_MAC_LEN,
599		  EAP_SIM_MAC_LEN);
600
601	return buf;
602}
603
604
605static struct wpabuf * eap_aka_build_notification(struct eap_sm *sm,
606						  struct eap_aka_data *data,
607						  u8 id)
608{
609	struct eap_sim_msg *msg;
610
611	wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Notification");
612	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
613			       EAP_AKA_SUBTYPE_NOTIFICATION);
614	wpa_printf(MSG_DEBUG, "   AT_NOTIFICATION (%d)", data->notification);
615	eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, data->notification,
616			NULL, 0);
617	if (data->use_result_ind) {
618		if (data->reauth) {
619			wpa_printf(MSG_DEBUG, "   AT_IV");
620			wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
621			eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
622						   EAP_SIM_AT_ENCR_DATA);
623			wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)",
624				   data->counter);
625			eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
626					NULL, 0);
627
628			if (eap_sim_msg_add_encr_end(msg, data->k_encr,
629						     EAP_SIM_AT_PADDING)) {
630				wpa_printf(MSG_WARNING, "EAP-AKA: Failed to "
631					   "encrypt AT_ENCR_DATA");
632				eap_sim_msg_free(msg);
633				return NULL;
634			}
635		}
636
637		wpa_printf(MSG_DEBUG, "   AT_MAC");
638		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
639	}
640	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, NULL, 0);
641}
642
643
644static struct wpabuf * eap_aka_buildReq(struct eap_sm *sm, void *priv, u8 id)
645{
646	struct eap_aka_data *data = priv;
647
648	data->auts_reported = 0;
649	switch (data->state) {
650	case IDENTITY:
651		return eap_aka_build_identity(sm, data, id);
652	case CHALLENGE:
653		return eap_aka_build_challenge(sm, data, id);
654	case REAUTH:
655		return eap_aka_build_reauth(sm, data, id);
656	case NOTIFICATION:
657		return eap_aka_build_notification(sm, data, id);
658	default:
659		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown state %d in "
660			   "buildReq", data->state);
661		break;
662	}
663	return NULL;
664}
665
666
667static bool eap_aka_check(struct eap_sm *sm, void *priv,
668			  struct wpabuf *respData)
669{
670	struct eap_aka_data *data = priv;
671	const u8 *pos;
672	size_t len;
673
674	pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, respData,
675			       &len);
676	if (pos == NULL || len < 3) {
677		wpa_printf(MSG_INFO, "EAP-AKA: Invalid frame");
678		return true;
679	}
680
681	return false;
682}
683
684
685static bool eap_aka_subtype_ok(struct eap_aka_data *data, u8 subtype)
686{
687	if (subtype == EAP_AKA_SUBTYPE_CLIENT_ERROR ||
688	    subtype == EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT)
689		return false;
690
691	switch (data->state) {
692	case IDENTITY:
693		if (subtype != EAP_AKA_SUBTYPE_IDENTITY) {
694			wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
695				   "subtype %d", subtype);
696			return true;
697		}
698		break;
699	case CHALLENGE:
700		if (subtype != EAP_AKA_SUBTYPE_CHALLENGE &&
701		    subtype != EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE) {
702			wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
703				   "subtype %d", subtype);
704			return true;
705		}
706		break;
707	case REAUTH:
708		if (subtype != EAP_AKA_SUBTYPE_REAUTHENTICATION) {
709			wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
710				   "subtype %d", subtype);
711			return true;
712		}
713		break;
714	case NOTIFICATION:
715		if (subtype != EAP_AKA_SUBTYPE_NOTIFICATION) {
716			wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
717				   "subtype %d", subtype);
718			return true;
719		}
720		break;
721	default:
722		wpa_printf(MSG_INFO, "EAP-AKA: Unexpected state (%d) for "
723			   "processing a response", data->state);
724		return true;
725	}
726
727	return false;
728}
729
730
731static void eap_aka_determine_identity(struct eap_sm *sm,
732				       struct eap_aka_data *data)
733{
734	char *username;
735
736	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Identity",
737			  sm->identity, sm->identity_len);
738
739	username = sim_get_username(sm->identity, sm->identity_len);
740	if (username == NULL) {
741		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
742		eap_aka_state(data, NOTIFICATION);
743		return;
744	}
745
746	if (eap_aka_check_identity_reauth(sm, data, username) > 0) {
747		os_free(username);
748		return;
749	}
750
751	if (((data->eap_method == EAP_TYPE_AKA_PRIME &&
752	      username[0] == EAP_AKA_PRIME_REAUTH_ID_PREFIX) ||
753	     (data->eap_method == EAP_TYPE_AKA &&
754	      username[0] == EAP_AKA_REAUTH_ID_PREFIX)) &&
755	    data->identity_round == 1) {
756		/* Remain in IDENTITY state for another round to request full
757		 * auth identity since we did not recognize reauth id */
758		os_free(username);
759		return;
760	}
761
762	if ((data->eap_method == EAP_TYPE_AKA_PRIME &&
763	     username[0] == EAP_AKA_PRIME_PSEUDONYM_PREFIX) ||
764	    (data->eap_method == EAP_TYPE_AKA &&
765	     username[0] == EAP_AKA_PSEUDONYM_PREFIX)) {
766		const char *permanent;
767		wpa_printf(MSG_DEBUG, "EAP-AKA: Pseudonym username '%s'",
768			   username);
769		permanent = eap_sim_db_get_permanent(
770			sm->cfg->eap_sim_db_priv, username);
771		os_free(username);
772		if (permanent == NULL) {
773			wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown pseudonym "
774				   "identity - request permanent identity");
775			/* Remain in IDENTITY state for another round */
776			return;
777		}
778		os_strlcpy(data->permanent, permanent,
779			   sizeof(data->permanent));
780	} else if ((data->eap_method == EAP_TYPE_AKA_PRIME &&
781		    username[0] == EAP_AKA_PRIME_PERMANENT_PREFIX) ||
782		   (data->eap_method == EAP_TYPE_AKA &&
783		    username[0] == EAP_AKA_PERMANENT_PREFIX)) {
784		wpa_printf(MSG_DEBUG, "EAP-AKA: Permanent username '%s'",
785			   username);
786		os_strlcpy(data->permanent, username, sizeof(data->permanent));
787		os_free(username);
788	} else {
789		wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized username '%s'",
790			   username);
791		os_free(username);
792		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
793		eap_aka_state(data, NOTIFICATION);
794		return;
795	}
796
797	eap_aka_fullauth(sm, data);
798}
799
800
801static void eap_aka_fullauth(struct eap_sm *sm, struct eap_aka_data *data)
802{
803	size_t identity_len;
804	int res;
805
806	res = eap_sim_db_get_aka_auth(sm->cfg->eap_sim_db_priv, data->permanent,
807				      data->rand, data->autn, data->ik,
808				      data->ck, data->res, &data->res_len, sm);
809	if (res == EAP_SIM_DB_PENDING) {
810		wpa_printf(MSG_DEBUG, "EAP-AKA: AKA authentication data "
811			   "not yet available - pending request");
812		sm->method_pending = METHOD_PENDING_WAIT;
813		return;
814	}
815
816	if (data->permanent[0] == EAP_AKA_PERMANENT_PREFIX ||
817	    data->permanent[0] == EAP_AKA_PRIME_PERMANENT_PREFIX)
818		os_strlcpy(sm->imsi, &data->permanent[1], sizeof(sm->imsi));
819
820#ifdef EAP_SERVER_AKA_PRIME
821	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
822		/* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
823		 * needed 6-octet SQN ^AK for CK',IK' derivation */
824		eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
825						 data->autn,
826						 data->network_name,
827						 data->network_name_len);
828	}
829#endif /* EAP_SERVER_AKA_PRIME */
830
831	data->reauth = NULL;
832	data->counter = 0; /* reset re-auth counter since this is full auth */
833
834	if (res != 0) {
835		wpa_printf(MSG_INFO, "EAP-AKA: Failed to get AKA "
836			   "authentication data for the peer");
837		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
838		eap_aka_state(data, NOTIFICATION);
839		return;
840	}
841	if (sm->method_pending == METHOD_PENDING_WAIT) {
842		wpa_printf(MSG_DEBUG, "EAP-AKA: AKA authentication data "
843			   "available - abort pending wait");
844		sm->method_pending = METHOD_PENDING_NONE;
845	}
846
847	identity_len = sm->identity_len;
848	while (identity_len > 0 && sm->identity[identity_len - 1] == '\0') {
849		wpa_printf(MSG_DEBUG, "EAP-AKA: Workaround - drop last null "
850			   "character from identity");
851		identity_len--;
852	}
853	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Identity for MK derivation",
854			  sm->identity, identity_len);
855
856	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
857		eap_aka_prime_derive_keys(sm->identity, identity_len, data->ik,
858					  data->ck, data->k_encr, data->k_aut,
859					  data->k_re, data->msk, data->emsk);
860	} else {
861		eap_aka_derive_mk(sm->identity, identity_len, data->ik,
862				  data->ck, data->mk);
863		eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
864				    data->msk, data->emsk);
865	}
866
867	eap_aka_state(data, CHALLENGE);
868}
869
870
871static void eap_aka_process_identity(struct eap_sm *sm,
872				     struct eap_aka_data *data,
873				     struct wpabuf *respData,
874				     struct eap_sim_attrs *attr)
875{
876	u8 *new_identity;
877
878	wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Identity");
879
880	if (attr->mac || attr->iv || attr->encr_data) {
881		wpa_printf(MSG_WARNING, "EAP-AKA: Unexpected attribute "
882			   "received in EAP-Response/AKA-Identity");
883		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
884		eap_aka_state(data, NOTIFICATION);
885		return;
886	}
887
888	/*
889	 * We always request identity with AKA/Identity, so the peer is
890	 * required to have replied with one.
891	 */
892	if (!attr->identity || attr->identity_len == 0) {
893		wpa_printf(MSG_DEBUG, "EAP-AKA: Peer did not provide any "
894			   "identity");
895		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
896		eap_aka_state(data, NOTIFICATION);
897		return;
898	}
899
900	new_identity = os_malloc(attr->identity_len);
901	if (new_identity == NULL) {
902		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
903		eap_aka_state(data, NOTIFICATION);
904		return;
905	}
906	os_free(sm->identity);
907	sm->identity = new_identity;
908	os_memcpy(sm->identity, attr->identity, attr->identity_len);
909	sm->identity_len = attr->identity_len;
910
911	eap_aka_determine_identity(sm, data);
912	if (eap_get_id(respData) == data->pending_id) {
913		data->pending_id = -1;
914		eap_aka_add_id_msg(data, respData);
915	}
916}
917
918
919static int eap_aka_verify_mac(struct eap_aka_data *data,
920			      const struct wpabuf *req,
921			      const u8 *mac, const u8 *extra,
922			      size_t extra_len)
923{
924	if (data->eap_method == EAP_TYPE_AKA_PRIME)
925		return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
926						 extra_len);
927	return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
928}
929
930
931static void eap_aka_process_challenge(struct eap_sm *sm,
932				      struct eap_aka_data *data,
933				      struct wpabuf *respData,
934				      struct eap_sim_attrs *attr)
935{
936	wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Challenge");
937
938#ifdef EAP_SERVER_AKA_PRIME
939#if 0
940	/* KDF negotiation; to be enabled only after more than one KDF is
941	 * supported */
942	if (data->eap_method == EAP_TYPE_AKA_PRIME &&
943	    attr->kdf_count == 1 && attr->mac == NULL) {
944		if (attr->kdf[0] != EAP_AKA_PRIME_KDF) {
945			wpa_printf(MSG_WARNING, "EAP-AKA': Peer selected "
946				   "unknown KDF");
947			data->notification =
948				EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
949			eap_aka_state(data, NOTIFICATION);
950			return;
951		}
952
953		data->kdf = attr->kdf[0];
954
955		/* Allow negotiation to continue with the selected KDF by
956		 * sending another Challenge message */
957		wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
958		return;
959	}
960#endif
961#endif /* EAP_SERVER_AKA_PRIME */
962
963	if (attr->checkcode &&
964	    eap_aka_verify_checkcode(data, attr->checkcode,
965				     attr->checkcode_len)) {
966		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
967			   "message");
968		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
969		eap_aka_state(data, NOTIFICATION);
970		return;
971	}
972	if (attr->mac == NULL ||
973	    eap_aka_verify_mac(data, respData, attr->mac, NULL, 0)) {
974		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
975			   "did not include valid AT_MAC");
976		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
977		eap_aka_state(data, NOTIFICATION);
978		return;
979	}
980
981	/*
982	 * AT_RES is padded, so verify that there is enough room for RES and
983	 * that the RES length in bits matches with the expected RES.
984	 */
985	if (attr->res == NULL || attr->res_len < data->res_len ||
986	    attr->res_len_bits != data->res_len * 8 ||
987	    os_memcmp_const(attr->res, data->res, data->res_len) != 0) {
988		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message did not "
989			   "include valid AT_RES (attr len=%lu, res len=%lu "
990			   "bits, expected %lu bits)",
991			   (unsigned long) attr->res_len,
992			   (unsigned long) attr->res_len_bits,
993			   (unsigned long) data->res_len * 8);
994		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
995		eap_aka_state(data, NOTIFICATION);
996		return;
997	}
998
999	wpa_printf(MSG_DEBUG, "EAP-AKA: Challenge response includes the "
1000		   "correct AT_MAC");
1001	if (sm->cfg->eap_sim_aka_result_ind && attr->result_ind) {
1002		data->use_result_ind = 1;
1003		data->notification = EAP_SIM_SUCCESS;
1004		eap_aka_state(data, NOTIFICATION);
1005	} else
1006		eap_aka_state(data, SUCCESS);
1007
1008	if (data->next_pseudonym) {
1009		eap_sim_db_add_pseudonym(sm->cfg->eap_sim_db_priv,
1010					 data->permanent,
1011					 data->next_pseudonym);
1012		data->next_pseudonym = NULL;
1013	}
1014	if (data->next_reauth_id) {
1015		if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1016#ifdef EAP_SERVER_AKA_PRIME
1017			eap_sim_db_add_reauth_prime(sm->cfg->eap_sim_db_priv,
1018						    data->permanent,
1019						    data->next_reauth_id,
1020						    data->counter + 1,
1021						    data->k_encr, data->k_aut,
1022						    data->k_re);
1023#endif /* EAP_SERVER_AKA_PRIME */
1024		} else {
1025			eap_sim_db_add_reauth(sm->cfg->eap_sim_db_priv,
1026					      data->permanent,
1027					      data->next_reauth_id,
1028					      data->counter + 1,
1029					      data->mk);
1030		}
1031		data->next_reauth_id = NULL;
1032	}
1033}
1034
1035
1036static void eap_aka_process_sync_failure(struct eap_sm *sm,
1037					 struct eap_aka_data *data,
1038					 struct wpabuf *respData,
1039					 struct eap_sim_attrs *attr)
1040{
1041	wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Synchronization-Failure");
1042
1043	if (attr->auts == NULL) {
1044		wpa_printf(MSG_WARNING, "EAP-AKA: Synchronization-Failure "
1045			   "message did not include valid AT_AUTS");
1046		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1047		eap_aka_state(data, NOTIFICATION);
1048		return;
1049	}
1050
1051	/* Avoid re-reporting AUTS when processing pending EAP packet by
1052	 * maintaining a local flag stating whether this AUTS has already been
1053	 * reported. */
1054	if (!data->auts_reported &&
1055	    eap_sim_db_resynchronize(sm->cfg->eap_sim_db_priv, data->permanent,
1056				     attr->auts, data->rand)) {
1057		wpa_printf(MSG_WARNING, "EAP-AKA: Resynchronization failed");
1058		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1059		eap_aka_state(data, NOTIFICATION);
1060		return;
1061	}
1062	data->auts_reported = 1;
1063
1064	/* Remain in CHALLENGE state to re-try after resynchronization */
1065	eap_aka_fullauth(sm, data);
1066}
1067
1068
1069static void eap_aka_process_reauth(struct eap_sm *sm,
1070				   struct eap_aka_data *data,
1071				   struct wpabuf *respData,
1072				   struct eap_sim_attrs *attr)
1073{
1074	struct eap_sim_attrs eattr;
1075	u8 *decrypted = NULL;
1076
1077	wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Reauthentication");
1078
1079	if (attr->mac == NULL ||
1080	    eap_aka_verify_mac(data, respData, attr->mac, data->nonce_s,
1081			       EAP_SIM_NONCE_S_LEN)) {
1082		wpa_printf(MSG_WARNING, "EAP-AKA: Re-authentication message "
1083			   "did not include valid AT_MAC");
1084		goto fail;
1085	}
1086
1087	if (attr->encr_data == NULL || attr->iv == NULL) {
1088		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1089			   "message did not include encrypted data");
1090		goto fail;
1091	}
1092
1093	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1094				       attr->encr_data_len, attr->iv, &eattr,
1095				       0);
1096	if (decrypted == NULL) {
1097		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1098			   "data from reauthentication message");
1099		goto fail;
1100	}
1101
1102	if (eattr.counter != data->counter) {
1103		wpa_printf(MSG_WARNING, "EAP-AKA: Re-authentication message "
1104			   "used incorrect counter %u, expected %u",
1105			   eattr.counter, data->counter);
1106		goto fail;
1107	}
1108	os_free(decrypted);
1109	decrypted = NULL;
1110
1111	wpa_printf(MSG_DEBUG, "EAP-AKA: Re-authentication response includes "
1112		   "the correct AT_MAC");
1113
1114	if (eattr.counter_too_small) {
1115		wpa_printf(MSG_DEBUG, "EAP-AKA: Re-authentication response "
1116			   "included AT_COUNTER_TOO_SMALL - starting full "
1117			   "authentication");
1118		eap_aka_fullauth(sm, data);
1119		return;
1120	}
1121
1122	if (sm->cfg->eap_sim_aka_result_ind && attr->result_ind) {
1123		data->use_result_ind = 1;
1124		data->notification = EAP_SIM_SUCCESS;
1125		eap_aka_state(data, NOTIFICATION);
1126	} else
1127		eap_aka_state(data, SUCCESS);
1128
1129	if (data->next_reauth_id) {
1130		if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1131#ifdef EAP_SERVER_AKA_PRIME
1132			eap_sim_db_add_reauth_prime(sm->cfg->eap_sim_db_priv,
1133						    data->permanent,
1134						    data->next_reauth_id,
1135						    data->counter + 1,
1136						    data->k_encr, data->k_aut,
1137						    data->k_re);
1138#endif /* EAP_SERVER_AKA_PRIME */
1139		} else {
1140			eap_sim_db_add_reauth(sm->cfg->eap_sim_db_priv,
1141					      data->permanent,
1142					      data->next_reauth_id,
1143					      data->counter + 1,
1144					      data->mk);
1145		}
1146		data->next_reauth_id = NULL;
1147	} else {
1148		eap_sim_db_remove_reauth(sm->cfg->eap_sim_db_priv,
1149					 data->reauth);
1150		data->reauth = NULL;
1151	}
1152
1153	return;
1154
1155fail:
1156	data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1157	eap_aka_state(data, NOTIFICATION);
1158	eap_sim_db_remove_reauth(sm->cfg->eap_sim_db_priv, data->reauth);
1159	data->reauth = NULL;
1160	os_free(decrypted);
1161}
1162
1163
1164static void eap_aka_process_client_error(struct eap_sm *sm,
1165					 struct eap_aka_data *data,
1166					 struct wpabuf *respData,
1167					 struct eap_sim_attrs *attr)
1168{
1169	wpa_printf(MSG_DEBUG, "EAP-AKA: Client reported error %d",
1170		   attr->client_error_code);
1171	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
1172		eap_aka_state(data, SUCCESS);
1173	else
1174		eap_aka_state(data, FAILURE);
1175}
1176
1177
1178static void eap_aka_process_authentication_reject(
1179	struct eap_sm *sm, struct eap_aka_data *data,
1180	struct wpabuf *respData, struct eap_sim_attrs *attr)
1181{
1182	wpa_printf(MSG_DEBUG, "EAP-AKA: Client rejected authentication");
1183	eap_aka_state(data, FAILURE);
1184}
1185
1186
1187static void eap_aka_process_notification(struct eap_sm *sm,
1188					 struct eap_aka_data *data,
1189					 struct wpabuf *respData,
1190					 struct eap_sim_attrs *attr)
1191{
1192	wpa_printf(MSG_DEBUG, "EAP-AKA: Client replied to notification");
1193	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
1194		eap_aka_state(data, SUCCESS);
1195	else
1196		eap_aka_state(data, FAILURE);
1197}
1198
1199
1200static void eap_aka_process(struct eap_sm *sm, void *priv,
1201			    struct wpabuf *respData)
1202{
1203	struct eap_aka_data *data = priv;
1204	const u8 *pos, *end;
1205	u8 subtype;
1206	size_t len;
1207	struct eap_sim_attrs attr;
1208
1209	pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, respData,
1210			       &len);
1211	if (pos == NULL || len < 3)
1212		return;
1213
1214	end = pos + len;
1215	subtype = *pos;
1216	pos += 3;
1217
1218	if (eap_aka_subtype_ok(data, subtype)) {
1219		wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized or unexpected "
1220			   "EAP-AKA Subtype in EAP Response");
1221		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1222		eap_aka_state(data, NOTIFICATION);
1223		return;
1224	}
1225
1226	if (eap_sim_parse_attr(pos, end, &attr,
1227			       data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1228			       0)) {
1229		wpa_printf(MSG_DEBUG, "EAP-AKA: Failed to parse attributes");
1230		data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1231		eap_aka_state(data, NOTIFICATION);
1232		return;
1233	}
1234
1235	if (subtype == EAP_AKA_SUBTYPE_CLIENT_ERROR) {
1236		eap_aka_process_client_error(sm, data, respData, &attr);
1237		return;
1238	}
1239
1240	if (subtype == EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT) {
1241		eap_aka_process_authentication_reject(sm, data, respData,
1242						      &attr);
1243		return;
1244	}
1245
1246	switch (data->state) {
1247	case IDENTITY:
1248		eap_aka_process_identity(sm, data, respData, &attr);
1249		break;
1250	case CHALLENGE:
1251		if (subtype == EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE) {
1252			eap_aka_process_sync_failure(sm, data, respData,
1253						     &attr);
1254		} else {
1255			eap_aka_process_challenge(sm, data, respData, &attr);
1256		}
1257		break;
1258	case REAUTH:
1259		eap_aka_process_reauth(sm, data, respData, &attr);
1260		break;
1261	case NOTIFICATION:
1262		eap_aka_process_notification(sm, data, respData, &attr);
1263		break;
1264	default:
1265		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown state %d in "
1266			   "process", data->state);
1267		break;
1268	}
1269}
1270
1271
1272static bool eap_aka_isDone(struct eap_sm *sm, void *priv)
1273{
1274	struct eap_aka_data *data = priv;
1275	return data->state == SUCCESS || data->state == FAILURE;
1276}
1277
1278
1279static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1280{
1281	struct eap_aka_data *data = priv;
1282	u8 *key;
1283
1284	if (data->state != SUCCESS)
1285		return NULL;
1286
1287	key = os_memdup(data->msk, EAP_SIM_KEYING_DATA_LEN);
1288	if (key == NULL)
1289		return NULL;
1290	*len = EAP_SIM_KEYING_DATA_LEN;
1291	return key;
1292}
1293
1294
1295static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1296{
1297	struct eap_aka_data *data = priv;
1298	u8 *key;
1299
1300	if (data->state != SUCCESS)
1301		return NULL;
1302
1303	key = os_memdup(data->emsk, EAP_EMSK_LEN);
1304	if (key == NULL)
1305		return NULL;
1306	*len = EAP_EMSK_LEN;
1307	return key;
1308}
1309
1310
1311static bool eap_aka_isSuccess(struct eap_sm *sm, void *priv)
1312{
1313	struct eap_aka_data *data = priv;
1314	return data->state == SUCCESS;
1315}
1316
1317
1318static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1319{
1320	struct eap_aka_data *data = priv;
1321	u8 *id;
1322
1323	if (data->state != SUCCESS)
1324		return NULL;
1325
1326	if (!data->reauth)
1327		*len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1328	else
1329		*len = 1 + EAP_SIM_NONCE_S_LEN + EAP_SIM_MAC_LEN;
1330	id = os_malloc(*len);
1331	if (id == NULL)
1332		return NULL;
1333
1334	id[0] = data->eap_method;
1335	if (!data->reauth) {
1336		os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1337		os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn,
1338			  EAP_AKA_AUTN_LEN);
1339	} else {
1340		os_memcpy(id + 1, data->nonce_s, EAP_SIM_NONCE_S_LEN);
1341		os_memcpy(id + 1 + EAP_SIM_NONCE_S_LEN, data->reauth_mac,
1342			  EAP_SIM_MAC_LEN);
1343	}
1344	wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1345
1346	return id;
1347}
1348
1349
1350int eap_server_aka_register(void)
1351{
1352	struct eap_method *eap;
1353
1354	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
1355				      EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1356	if (eap == NULL)
1357		return -1;
1358
1359	eap->init = eap_aka_init;
1360	eap->reset = eap_aka_reset;
1361	eap->buildReq = eap_aka_buildReq;
1362	eap->check = eap_aka_check;
1363	eap->process = eap_aka_process;
1364	eap->isDone = eap_aka_isDone;
1365	eap->getKey = eap_aka_getKey;
1366	eap->isSuccess = eap_aka_isSuccess;
1367	eap->get_emsk = eap_aka_get_emsk;
1368	eap->getSessionId = eap_aka_get_session_id;
1369
1370	return eap_server_method_register(eap);
1371}
1372
1373
1374#ifdef EAP_SERVER_AKA_PRIME
1375int eap_server_aka_prime_register(void)
1376{
1377	struct eap_method *eap;
1378
1379	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
1380				      EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1381				      "AKA'");
1382	if (eap == NULL)
1383		return -1;
1384
1385	eap->init = eap_aka_prime_init;
1386	eap->reset = eap_aka_reset;
1387	eap->buildReq = eap_aka_buildReq;
1388	eap->check = eap_aka_check;
1389	eap->process = eap_aka_process;
1390	eap->isDone = eap_aka_isDone;
1391	eap->getKey = eap_aka_getKey;
1392	eap->isSuccess = eap_aka_isSuccess;
1393	eap->get_emsk = eap_aka_get_emsk;
1394	eap->getSessionId = eap_aka_get_session_id;
1395
1396	return eap_server_method_register(eap);
1397}
1398#endif /* EAP_SERVER_AKA_PRIME */
1399