xref: /freebsd/contrib/wpa/src/eap_peer/eap_aka.c (revision 8d20be1e22095c27faf8fe8b2f0d089739cc742e)
1 /*
2  * EAP peer method: EAP-AKA (RFC 4187) and EAP-AKA' (RFC 5448)
3  * Copyright (c) 2004-2012, 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 "pcsc_funcs.h"
13 #include "crypto/crypto.h"
14 #include "crypto/sha1.h"
15 #include "crypto/sha256.h"
16 #include "crypto/milenage.h"
17 #include "eap_common/eap_sim_common.h"
18 #include "eap_config.h"
19 #include "eap_i.h"
20 
21 
22 struct eap_aka_data {
23 	u8 ik[EAP_AKA_IK_LEN], ck[EAP_AKA_CK_LEN], res[EAP_AKA_RES_MAX_LEN];
24 	size_t res_len;
25 	u8 nonce_s[EAP_SIM_NONCE_S_LEN];
26 	u8 mk[EAP_SIM_MK_LEN];
27 	u8 k_aut[EAP_AKA_PRIME_K_AUT_LEN];
28 	u8 k_encr[EAP_SIM_K_ENCR_LEN];
29 	u8 k_re[EAP_AKA_PRIME_K_RE_LEN]; /* EAP-AKA' only */
30 	u8 msk[EAP_SIM_KEYING_DATA_LEN];
31 	u8 emsk[EAP_EMSK_LEN];
32 	u8 rand[EAP_AKA_RAND_LEN], autn[EAP_AKA_AUTN_LEN];
33 	u8 auts[EAP_AKA_AUTS_LEN];
34 
35 	int num_id_req, num_notification;
36 	u8 *pseudonym;
37 	size_t pseudonym_len;
38 	u8 *reauth_id;
39 	size_t reauth_id_len;
40 	int reauth;
41 	unsigned int counter, counter_too_small;
42 	u8 *last_eap_identity;
43 	size_t last_eap_identity_len;
44 	enum {
45 		CONTINUE, RESULT_SUCCESS, RESULT_FAILURE, SUCCESS, FAILURE
46 	} state;
47 
48 	struct wpabuf *id_msgs;
49 	int prev_id;
50 	int result_ind, use_result_ind;
51 	u8 eap_method;
52 	u8 *network_name;
53 	size_t network_name_len;
54 	u16 kdf;
55 	int kdf_negotiation;
56 };
57 
58 
59 #ifndef CONFIG_NO_STDOUT_DEBUG
60 static const char * eap_aka_state_txt(int state)
61 {
62 	switch (state) {
63 	case CONTINUE:
64 		return "CONTINUE";
65 	case RESULT_SUCCESS:
66 		return "RESULT_SUCCESS";
67 	case RESULT_FAILURE:
68 		return "RESULT_FAILURE";
69 	case SUCCESS:
70 		return "SUCCESS";
71 	case FAILURE:
72 		return "FAILURE";
73 	default:
74 		return "?";
75 	}
76 }
77 #endif /* CONFIG_NO_STDOUT_DEBUG */
78 
79 
80 static void eap_aka_state(struct eap_aka_data *data, int state)
81 {
82 	wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
83 		   eap_aka_state_txt(data->state),
84 		   eap_aka_state_txt(state));
85 	data->state = state;
86 }
87 
88 
89 static void * eap_aka_init(struct eap_sm *sm)
90 {
91 	struct eap_aka_data *data;
92 	const char *phase1 = eap_get_config_phase1(sm);
93 	struct eap_peer_config *config = eap_get_config(sm);
94 
95 	data = os_zalloc(sizeof(*data));
96 	if (data == NULL)
97 		return NULL;
98 
99 	data->eap_method = EAP_TYPE_AKA;
100 
101 	eap_aka_state(data, CONTINUE);
102 	data->prev_id = -1;
103 
104 	data->result_ind = phase1 && os_strstr(phase1, "result_ind=1") != NULL;
105 
106 	if (config && config->anonymous_identity) {
107 		data->pseudonym = os_malloc(config->anonymous_identity_len);
108 		if (data->pseudonym) {
109 			os_memcpy(data->pseudonym, config->anonymous_identity,
110 				  config->anonymous_identity_len);
111 			data->pseudonym_len = config->anonymous_identity_len;
112 		}
113 	}
114 
115 	return data;
116 }
117 
118 
119 #ifdef EAP_AKA_PRIME
120 static void * eap_aka_prime_init(struct eap_sm *sm)
121 {
122 	struct eap_aka_data *data = eap_aka_init(sm);
123 	if (data == NULL)
124 		return NULL;
125 	data->eap_method = EAP_TYPE_AKA_PRIME;
126 	return data;
127 }
128 #endif /* EAP_AKA_PRIME */
129 
130 
131 static void eap_aka_deinit(struct eap_sm *sm, void *priv)
132 {
133 	struct eap_aka_data *data = priv;
134 	if (data) {
135 		os_free(data->pseudonym);
136 		os_free(data->reauth_id);
137 		os_free(data->last_eap_identity);
138 		wpabuf_free(data->id_msgs);
139 		os_free(data->network_name);
140 		os_free(data);
141 	}
142 }
143 
144 
145 static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data)
146 {
147 	struct eap_peer_config *conf;
148 
149 	wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm");
150 
151 	conf = eap_get_config(sm);
152 	if (conf == NULL)
153 		return -1;
154 	if (conf->pcsc) {
155 		return scard_umts_auth(sm->scard_ctx, data->rand,
156 				       data->autn, data->res, &data->res_len,
157 				       data->ik, data->ck, data->auts);
158 	}
159 
160 #ifdef CONFIG_USIM_SIMULATOR
161 	if (conf->password) {
162 		u8 opc[16], k[16], sqn[6];
163 		const char *pos;
164 		wpa_printf(MSG_DEBUG, "EAP-AKA: Use internal Milenage "
165 			   "implementation for UMTS authentication");
166 		if (conf->password_len < 78) {
167 			wpa_printf(MSG_DEBUG, "EAP-AKA: invalid Milenage "
168 				   "password");
169 			return -1;
170 		}
171 		pos = (const char *) conf->password;
172 		if (hexstr2bin(pos, k, 16))
173 			return -1;
174 		pos += 32;
175 		if (*pos != ':')
176 			return -1;
177 		pos++;
178 
179 		if (hexstr2bin(pos, opc, 16))
180 			return -1;
181 		pos += 32;
182 		if (*pos != ':')
183 			return -1;
184 		pos++;
185 
186 		if (hexstr2bin(pos, sqn, 6))
187 			return -1;
188 
189 		return milenage_check(opc, k, sqn, data->rand, data->autn,
190 				      data->ik, data->ck,
191 				      data->res, &data->res_len, data->auts);
192 	}
193 #endif /* CONFIG_USIM_SIMULATOR */
194 
195 #ifdef CONFIG_USIM_HARDCODED
196 	wpa_printf(MSG_DEBUG, "EAP-AKA: Use hardcoded Kc and SRES values for "
197 		   "testing");
198 
199 	/* These hardcoded Kc and SRES values are used for testing.
200 	 * Could consider making them configurable. */
201 	os_memset(data->res, '2', EAP_AKA_RES_MAX_LEN);
202 	data->res_len = EAP_AKA_RES_MAX_LEN;
203 	os_memset(data->ik, '3', EAP_AKA_IK_LEN);
204 	os_memset(data->ck, '4', EAP_AKA_CK_LEN);
205 	{
206 		u8 autn[EAP_AKA_AUTN_LEN];
207 		os_memset(autn, '1', EAP_AKA_AUTN_LEN);
208 		if (os_memcmp(autn, data->autn, EAP_AKA_AUTN_LEN) != 0) {
209 			wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match "
210 				   "with expected value");
211 			return -1;
212 		}
213 	}
214 #if 0
215 	{
216 		static int test_resync = 1;
217 		if (test_resync) {
218 			/* Test Resynchronization */
219 			test_resync = 0;
220 			return -2;
221 		}
222 	}
223 #endif
224 	return 0;
225 
226 #else /* CONFIG_USIM_HARDCODED */
227 
228 	wpa_printf(MSG_DEBUG, "EAP-AKA: No UMTS authentication algorith "
229 		   "enabled");
230 	return -1;
231 
232 #endif /* CONFIG_USIM_HARDCODED */
233 }
234 
235 
236 #define CLEAR_PSEUDONYM	0x01
237 #define CLEAR_REAUTH_ID	0x02
238 #define CLEAR_EAP_ID	0x04
239 
240 static void eap_aka_clear_identities(struct eap_sm *sm,
241 				     struct eap_aka_data *data, int id)
242 {
243 	if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
244 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old pseudonym");
245 		os_free(data->pseudonym);
246 		data->pseudonym = NULL;
247 		data->pseudonym_len = 0;
248 		eap_set_anon_id(sm, NULL, 0);
249 	}
250 	if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
251 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old reauth_id");
252 		os_free(data->reauth_id);
253 		data->reauth_id = NULL;
254 		data->reauth_id_len = 0;
255 	}
256 	if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
257 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old eap_id");
258 		os_free(data->last_eap_identity);
259 		data->last_eap_identity = NULL;
260 		data->last_eap_identity_len = 0;
261 	}
262 }
263 
264 
265 static int eap_aka_learn_ids(struct eap_sm *sm, struct eap_aka_data *data,
266 			     struct eap_sim_attrs *attr)
267 {
268 	if (attr->next_pseudonym) {
269 		const u8 *identity = NULL;
270 		size_t identity_len = 0;
271 		const u8 *realm = NULL;
272 		size_t realm_len = 0;
273 
274 		wpa_hexdump_ascii(MSG_DEBUG,
275 				  "EAP-AKA: (encr) AT_NEXT_PSEUDONYM",
276 				  attr->next_pseudonym,
277 				  attr->next_pseudonym_len);
278 		os_free(data->pseudonym);
279 		/* Look for the realm of the permanent identity */
280 		identity = eap_get_config_identity(sm, &identity_len);
281 		if (identity) {
282 			for (realm = identity, realm_len = identity_len;
283 			     realm_len > 0; realm_len--, realm++) {
284 				if (*realm == '@')
285 					break;
286 			}
287 		}
288 		data->pseudonym = os_malloc(attr->next_pseudonym_len +
289 					    realm_len);
290 		if (data->pseudonym == NULL) {
291 			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
292 				   "next pseudonym");
293 			data->pseudonym_len = 0;
294 			return -1;
295 		}
296 		os_memcpy(data->pseudonym, attr->next_pseudonym,
297 			  attr->next_pseudonym_len);
298 		if (realm_len) {
299 			os_memcpy(data->pseudonym + attr->next_pseudonym_len,
300 				  realm, realm_len);
301 		}
302 		data->pseudonym_len = attr->next_pseudonym_len + realm_len;
303 		eap_set_anon_id(sm, data->pseudonym, data->pseudonym_len);
304 	}
305 
306 	if (attr->next_reauth_id) {
307 		os_free(data->reauth_id);
308 		data->reauth_id = os_malloc(attr->next_reauth_id_len);
309 		if (data->reauth_id == NULL) {
310 			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
311 				   "next reauth_id");
312 			data->reauth_id_len = 0;
313 			return -1;
314 		}
315 		os_memcpy(data->reauth_id, attr->next_reauth_id,
316 			  attr->next_reauth_id_len);
317 		data->reauth_id_len = attr->next_reauth_id_len;
318 		wpa_hexdump_ascii(MSG_DEBUG,
319 				  "EAP-AKA: (encr) AT_NEXT_REAUTH_ID",
320 				  data->reauth_id,
321 				  data->reauth_id_len);
322 	}
323 
324 	return 0;
325 }
326 
327 
328 static int eap_aka_add_id_msg(struct eap_aka_data *data,
329 			      const struct wpabuf *msg)
330 {
331 	if (msg == NULL)
332 		return -1;
333 
334 	if (data->id_msgs == NULL) {
335 		data->id_msgs = wpabuf_dup(msg);
336 		return data->id_msgs == NULL ? -1 : 0;
337 	}
338 
339 	if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
340 		return -1;
341 	wpabuf_put_buf(data->id_msgs, msg);
342 
343 	return 0;
344 }
345 
346 
347 static void eap_aka_add_checkcode(struct eap_aka_data *data,
348 				  struct eap_sim_msg *msg)
349 {
350 	const u8 *addr;
351 	size_t len;
352 	u8 hash[SHA256_MAC_LEN];
353 
354 	wpa_printf(MSG_DEBUG, "   AT_CHECKCODE");
355 
356 	if (data->id_msgs == NULL) {
357 		/*
358 		 * No EAP-AKA/Identity packets were exchanged - send empty
359 		 * checkcode.
360 		 */
361 		eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
362 		return;
363 	}
364 
365 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
366 	addr = wpabuf_head(data->id_msgs);
367 	len = wpabuf_len(data->id_msgs);
368 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
369 #ifdef EAP_AKA_PRIME
370 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
371 		sha256_vector(1, &addr, &len, hash);
372 	else
373 #endif /* EAP_AKA_PRIME */
374 		sha1_vector(1, &addr, &len, hash);
375 
376 	eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
377 			data->eap_method == EAP_TYPE_AKA_PRIME ?
378 			EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
379 }
380 
381 
382 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
383 				    const u8 *checkcode, size_t checkcode_len)
384 {
385 	const u8 *addr;
386 	size_t len;
387 	u8 hash[SHA256_MAC_LEN];
388 	size_t hash_len;
389 
390 	if (checkcode == NULL)
391 		return -1;
392 
393 	if (data->id_msgs == NULL) {
394 		if (checkcode_len != 0) {
395 			wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
396 				   "indicates that AKA/Identity messages were "
397 				   "used, but they were not");
398 			return -1;
399 		}
400 		return 0;
401 	}
402 
403 	hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
404 		EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
405 
406 	if (checkcode_len != hash_len) {
407 		wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
408 			   "indicates that AKA/Identity message were not "
409 			   "used, but they were");
410 		return -1;
411 	}
412 
413 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
414 	addr = wpabuf_head(data->id_msgs);
415 	len = wpabuf_len(data->id_msgs);
416 #ifdef EAP_AKA_PRIME
417 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
418 		sha256_vector(1, &addr, &len, hash);
419 	else
420 #endif /* EAP_AKA_PRIME */
421 		sha1_vector(1, &addr, &len, hash);
422 
423 	if (os_memcmp(hash, checkcode, hash_len) != 0) {
424 		wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
425 		return -1;
426 	}
427 
428 	return 0;
429 }
430 
431 
432 static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
433 					    int err)
434 {
435 	struct eap_sim_msg *msg;
436 
437 	eap_aka_state(data, FAILURE);
438 	data->num_id_req = 0;
439 	data->num_notification = 0;
440 
441 	wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
442 		   err);
443 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
444 			       EAP_AKA_SUBTYPE_CLIENT_ERROR);
445 	eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
446 	return eap_sim_msg_finish(msg, NULL, NULL, 0);
447 }
448 
449 
450 static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
451 						     u8 id)
452 {
453 	struct eap_sim_msg *msg;
454 
455 	eap_aka_state(data, FAILURE);
456 	data->num_id_req = 0;
457 	data->num_notification = 0;
458 
459 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
460 		   "(id=%d)", id);
461 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
462 			       EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
463 	return eap_sim_msg_finish(msg, NULL, NULL, 0);
464 }
465 
466 
467 static struct wpabuf * eap_aka_synchronization_failure(
468 	struct eap_aka_data *data, u8 id)
469 {
470 	struct eap_sim_msg *msg;
471 
472 	data->num_id_req = 0;
473 	data->num_notification = 0;
474 
475 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
476 		   "(id=%d)", id);
477 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
478 			       EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
479 	wpa_printf(MSG_DEBUG, "   AT_AUTS");
480 	eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
481 			     EAP_AKA_AUTS_LEN);
482 	return eap_sim_msg_finish(msg, NULL, NULL, 0);
483 }
484 
485 
486 static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
487 						 struct eap_aka_data *data,
488 						 u8 id,
489 						 enum eap_sim_id_req id_req)
490 {
491 	const u8 *identity = NULL;
492 	size_t identity_len = 0;
493 	struct eap_sim_msg *msg;
494 
495 	data->reauth = 0;
496 	if (id_req == ANY_ID && data->reauth_id) {
497 		identity = data->reauth_id;
498 		identity_len = data->reauth_id_len;
499 		data->reauth = 1;
500 	} else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
501 		   data->pseudonym) {
502 		identity = data->pseudonym;
503 		identity_len = data->pseudonym_len;
504 		eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
505 	} else if (id_req != NO_ID_REQ) {
506 		identity = eap_get_config_identity(sm, &identity_len);
507 		if (identity) {
508 			eap_aka_clear_identities(sm, data, CLEAR_PSEUDONYM |
509 						 CLEAR_REAUTH_ID);
510 		}
511 	}
512 	if (id_req != NO_ID_REQ)
513 		eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
514 
515 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
516 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
517 			       EAP_AKA_SUBTYPE_IDENTITY);
518 
519 	if (identity) {
520 		wpa_hexdump_ascii(MSG_DEBUG, "   AT_IDENTITY",
521 				  identity, identity_len);
522 		eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
523 				identity, identity_len);
524 	}
525 
526 	return eap_sim_msg_finish(msg, NULL, NULL, 0);
527 }
528 
529 
530 static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
531 						  u8 id)
532 {
533 	struct eap_sim_msg *msg;
534 
535 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
536 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
537 			       EAP_AKA_SUBTYPE_CHALLENGE);
538 	wpa_printf(MSG_DEBUG, "   AT_RES");
539 	eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
540 			data->res, data->res_len);
541 	eap_aka_add_checkcode(data, msg);
542 	if (data->use_result_ind) {
543 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
544 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
545 	}
546 	wpa_printf(MSG_DEBUG, "   AT_MAC");
547 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
548 	return eap_sim_msg_finish(msg, data->k_aut, (u8 *) "", 0);
549 }
550 
551 
552 static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
553 					       u8 id, int counter_too_small,
554 					       const u8 *nonce_s)
555 {
556 	struct eap_sim_msg *msg;
557 	unsigned int counter;
558 
559 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
560 		   id);
561 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
562 			       EAP_AKA_SUBTYPE_REAUTHENTICATION);
563 	wpa_printf(MSG_DEBUG, "   AT_IV");
564 	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
565 	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
566 
567 	if (counter_too_small) {
568 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER_TOO_SMALL");
569 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
570 		counter = data->counter_too_small;
571 	} else
572 		counter = data->counter;
573 
574 	wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", counter);
575 	eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
576 
577 	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
578 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
579 			   "AT_ENCR_DATA");
580 		eap_sim_msg_free(msg);
581 		return NULL;
582 	}
583 	eap_aka_add_checkcode(data, msg);
584 	if (data->use_result_ind) {
585 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
586 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
587 	}
588 	wpa_printf(MSG_DEBUG, "   AT_MAC");
589 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
590 	return eap_sim_msg_finish(msg, data->k_aut, nonce_s,
591 				  EAP_SIM_NONCE_S_LEN);
592 }
593 
594 
595 static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
596 						     u8 id, u16 notification)
597 {
598 	struct eap_sim_msg *msg;
599 	u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
600 
601 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
602 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
603 			       EAP_AKA_SUBTYPE_NOTIFICATION);
604 	if (k_aut && data->reauth) {
605 		wpa_printf(MSG_DEBUG, "   AT_IV");
606 		wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
607 		eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
608 					   EAP_SIM_AT_ENCR_DATA);
609 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", data->counter);
610 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
611 				NULL, 0);
612 		if (eap_sim_msg_add_encr_end(msg, data->k_encr,
613 					     EAP_SIM_AT_PADDING)) {
614 			wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
615 				   "AT_ENCR_DATA");
616 			eap_sim_msg_free(msg);
617 			return NULL;
618 		}
619 	}
620 	if (k_aut) {
621 		wpa_printf(MSG_DEBUG, "   AT_MAC");
622 		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
623 	}
624 	return eap_sim_msg_finish(msg, k_aut, (u8 *) "", 0);
625 }
626 
627 
628 static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
629 						struct eap_aka_data *data,
630 						u8 id,
631 						const struct wpabuf *reqData,
632 						struct eap_sim_attrs *attr)
633 {
634 	int id_error;
635 	struct wpabuf *buf;
636 
637 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
638 
639 	id_error = 0;
640 	switch (attr->id_req) {
641 	case NO_ID_REQ:
642 		break;
643 	case ANY_ID:
644 		if (data->num_id_req > 0)
645 			id_error++;
646 		data->num_id_req++;
647 		break;
648 	case FULLAUTH_ID:
649 		if (data->num_id_req > 1)
650 			id_error++;
651 		data->num_id_req++;
652 		break;
653 	case PERMANENT_ID:
654 		if (data->num_id_req > 2)
655 			id_error++;
656 		data->num_id_req++;
657 		break;
658 	}
659 	if (id_error) {
660 		wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
661 			   "used within one authentication");
662 		return eap_aka_client_error(data, id,
663 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
664 	}
665 
666 	buf = eap_aka_response_identity(sm, data, id, attr->id_req);
667 
668 	if (data->prev_id != id) {
669 		eap_aka_add_id_msg(data, reqData);
670 		eap_aka_add_id_msg(data, buf);
671 		data->prev_id = id;
672 	}
673 
674 	return buf;
675 }
676 
677 
678 static int eap_aka_verify_mac(struct eap_aka_data *data,
679 			      const struct wpabuf *req,
680 			      const u8 *mac, const u8 *extra,
681 			      size_t extra_len)
682 {
683 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
684 		return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
685 						 extra_len);
686 	return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
687 }
688 
689 
690 #ifdef EAP_AKA_PRIME
691 static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
692 						u8 id, u16 kdf)
693 {
694 	struct eap_sim_msg *msg;
695 
696 	data->kdf_negotiation = 1;
697 	data->kdf = kdf;
698 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
699 		   "select)", id);
700 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
701 			       EAP_AKA_SUBTYPE_CHALLENGE);
702 	wpa_printf(MSG_DEBUG, "   AT_KDF");
703 	eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
704 	return eap_sim_msg_finish(msg, NULL, NULL, 0);
705 }
706 
707 
708 static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
709 					     u8 id, struct eap_sim_attrs *attr)
710 {
711 	size_t i;
712 
713 	for (i = 0; i < attr->kdf_count; i++) {
714 		if (attr->kdf[i] == EAP_AKA_PRIME_KDF)
715 			return eap_aka_prime_kdf_select(data, id,
716 							EAP_AKA_PRIME_KDF);
717 	}
718 
719 	/* No matching KDF found - fail authentication as if AUTN had been
720 	 * incorrect */
721 	return eap_aka_authentication_reject(data, id);
722 }
723 
724 
725 static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
726 				   struct eap_sim_attrs *attr)
727 {
728 	size_t i, j;
729 
730 	if (attr->kdf_count == 0)
731 		return 0;
732 
733 	/* The only allowed (and required) duplication of a KDF is the addition
734 	 * of the selected KDF into the beginning of the list. */
735 
736 	if (data->kdf_negotiation) {
737 		if (attr->kdf[0] != data->kdf) {
738 			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
739 				   "accept the selected KDF");
740 			return 0;
741 		}
742 
743 		for (i = 1; i < attr->kdf_count; i++) {
744 			if (attr->kdf[i] == data->kdf)
745 				break;
746 		}
747 		if (i == attr->kdf_count &&
748 		    attr->kdf_count < EAP_AKA_PRIME_KDF_MAX) {
749 			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
750 				   "duplicate the selected KDF");
751 			return 0;
752 		}
753 
754 		/* TODO: should check that the list is identical to the one
755 		 * used in the previous Challenge message apart from the added
756 		 * entry in the beginning. */
757 	}
758 
759 	for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
760 		for (j = i + 1; j < attr->kdf_count; j++) {
761 			if (attr->kdf[i] == attr->kdf[j]) {
762 				wpa_printf(MSG_WARNING, "EAP-AKA': The server "
763 					   "included a duplicated KDF");
764 				return 0;
765 			}
766 		}
767 	}
768 
769 	return 1;
770 }
771 #endif /* EAP_AKA_PRIME */
772 
773 
774 static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
775 						 struct eap_aka_data *data,
776 						 u8 id,
777 						 const struct wpabuf *reqData,
778 						 struct eap_sim_attrs *attr)
779 {
780 	const u8 *identity;
781 	size_t identity_len;
782 	int res;
783 	struct eap_sim_attrs eattr;
784 
785 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
786 
787 	if (attr->checkcode &&
788 	    eap_aka_verify_checkcode(data, attr->checkcode,
789 				     attr->checkcode_len)) {
790 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
791 			   "message");
792 		return eap_aka_client_error(data, id,
793 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
794 	}
795 
796 #ifdef EAP_AKA_PRIME
797 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
798 		if (!attr->kdf_input || attr->kdf_input_len == 0) {
799 			wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
800 				   "did not include non-empty AT_KDF_INPUT");
801 			/* Fail authentication as if AUTN had been incorrect */
802 			return eap_aka_authentication_reject(data, id);
803 		}
804 		os_free(data->network_name);
805 		data->network_name = os_malloc(attr->kdf_input_len);
806 		if (data->network_name == NULL) {
807 			wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
808 				   "storing Network Name");
809 			return eap_aka_authentication_reject(data, id);
810 		}
811 		os_memcpy(data->network_name, attr->kdf_input,
812 			  attr->kdf_input_len);
813 		data->network_name_len = attr->kdf_input_len;
814 		wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
815 				  "(AT_KDF_INPUT)",
816 				  data->network_name, data->network_name_len);
817 		/* TODO: check Network Name per 3GPP.33.402 */
818 
819 		if (!eap_aka_prime_kdf_valid(data, attr))
820 			return eap_aka_authentication_reject(data, id);
821 
822 		if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
823 			return eap_aka_prime_kdf_neg(data, id, attr);
824 
825 		data->kdf = EAP_AKA_PRIME_KDF;
826 		wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
827 	}
828 
829 	if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
830 		u16 flags = WPA_GET_BE16(attr->bidding);
831 		if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
832 		    eap_allowed_method(sm, EAP_VENDOR_IETF,
833 				       EAP_TYPE_AKA_PRIME)) {
834 			wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
835 				   "AKA' to AKA detected");
836 			/* Fail authentication as if AUTN had been incorrect */
837 			return eap_aka_authentication_reject(data, id);
838 		}
839 	}
840 #endif /* EAP_AKA_PRIME */
841 
842 	data->reauth = 0;
843 	if (!attr->mac || !attr->rand || !attr->autn) {
844 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
845 			   "did not include%s%s%s",
846 			   !attr->mac ? " AT_MAC" : "",
847 			   !attr->rand ? " AT_RAND" : "",
848 			   !attr->autn ? " AT_AUTN" : "");
849 		return eap_aka_client_error(data, id,
850 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
851 	}
852 	os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
853 	os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
854 
855 	res = eap_aka_umts_auth(sm, data);
856 	if (res == -1) {
857 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
858 			   "failed (AUTN)");
859 		return eap_aka_authentication_reject(data, id);
860 	} else if (res == -2) {
861 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
862 			   "failed (AUTN seq# -> AUTS)");
863 		return eap_aka_synchronization_failure(data, id);
864 	} else if (res) {
865 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
866 		return eap_aka_client_error(data, id,
867 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
868 	}
869 #ifdef EAP_AKA_PRIME
870 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
871 		/* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
872 		 * needed 6-octet SQN ^ AK for CK',IK' derivation */
873 		u16 amf = WPA_GET_BE16(data->autn + 6);
874 		if (!(amf & 0x8000)) {
875 			wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
876 				   "not set (AMF=0x%4x)", amf);
877 			return eap_aka_authentication_reject(data, id);
878 		}
879 		eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
880 						 data->autn,
881 						 data->network_name,
882 						 data->network_name_len);
883 	}
884 #endif /* EAP_AKA_PRIME */
885 	if (data->last_eap_identity) {
886 		identity = data->last_eap_identity;
887 		identity_len = data->last_eap_identity_len;
888 	} else if (data->pseudonym) {
889 		identity = data->pseudonym;
890 		identity_len = data->pseudonym_len;
891 	} else
892 		identity = eap_get_config_identity(sm, &identity_len);
893 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
894 			  "derivation", identity, identity_len);
895 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
896 		eap_aka_prime_derive_keys(identity, identity_len, data->ik,
897 					  data->ck, data->k_encr, data->k_aut,
898 					  data->k_re, data->msk, data->emsk);
899 	} else {
900 		eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
901 				  data->mk);
902 		eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
903 				    data->msk, data->emsk);
904 	}
905 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
906 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
907 			   "used invalid AT_MAC");
908 		return eap_aka_client_error(data, id,
909 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
910 	}
911 
912 	/* Old reauthentication identity must not be used anymore. In
913 	 * other words, if no new identities are received, full
914 	 * authentication will be used on next reauthentication (using
915 	 * pseudonym identity or permanent identity). */
916 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
917 
918 	if (attr->encr_data) {
919 		u8 *decrypted;
920 		decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
921 					       attr->encr_data_len, attr->iv,
922 					       &eattr, 0);
923 		if (decrypted == NULL) {
924 			return eap_aka_client_error(
925 				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
926 		}
927 		eap_aka_learn_ids(sm, data, &eattr);
928 		os_free(decrypted);
929 	}
930 
931 	if (data->result_ind && attr->result_ind)
932 		data->use_result_ind = 1;
933 
934 	if (data->state != FAILURE && data->state != RESULT_FAILURE) {
935 		eap_aka_state(data, data->use_result_ind ?
936 			      RESULT_SUCCESS : SUCCESS);
937 	}
938 
939 	data->num_id_req = 0;
940 	data->num_notification = 0;
941 	/* RFC 4187 specifies that counter is initialized to one after
942 	 * fullauth, but initializing it to zero makes it easier to implement
943 	 * reauth verification. */
944 	data->counter = 0;
945 	return eap_aka_response_challenge(data, id);
946 }
947 
948 
949 static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
950 					       struct eap_sim_attrs *attr)
951 {
952 	struct eap_sim_attrs eattr;
953 	u8 *decrypted;
954 
955 	if (attr->encr_data == NULL || attr->iv == NULL) {
956 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
957 			   "reauth did not include encrypted data");
958 		return -1;
959 	}
960 
961 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
962 				       attr->encr_data_len, attr->iv, &eattr,
963 				       0);
964 	if (decrypted == NULL) {
965 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
966 			   "data from notification message");
967 		return -1;
968 	}
969 
970 	if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
971 		wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
972 			   "message does not match with counter in reauth "
973 			   "message");
974 		os_free(decrypted);
975 		return -1;
976 	}
977 
978 	os_free(decrypted);
979 	return 0;
980 }
981 
982 
983 static int eap_aka_process_notification_auth(struct eap_aka_data *data,
984 					     const struct wpabuf *reqData,
985 					     struct eap_sim_attrs *attr)
986 {
987 	if (attr->mac == NULL) {
988 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
989 			   "Notification message");
990 		return -1;
991 	}
992 
993 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
994 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
995 			   "used invalid AT_MAC");
996 		return -1;
997 	}
998 
999 	if (data->reauth &&
1000 	    eap_aka_process_notification_reauth(data, attr)) {
1001 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
1002 			   "message after reauth");
1003 		return -1;
1004 	}
1005 
1006 	return 0;
1007 }
1008 
1009 
1010 static struct wpabuf * eap_aka_process_notification(
1011 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1012 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1013 {
1014 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
1015 	if (data->num_notification > 0) {
1016 		wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
1017 			   "rounds (only one allowed)");
1018 		return eap_aka_client_error(data, id,
1019 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1020 	}
1021 	data->num_notification++;
1022 	if (attr->notification == -1) {
1023 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
1024 			   "Notification message");
1025 		return eap_aka_client_error(data, id,
1026 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1027 	}
1028 
1029 	if ((attr->notification & 0x4000) == 0 &&
1030 	    eap_aka_process_notification_auth(data, reqData, attr)) {
1031 		return eap_aka_client_error(data, id,
1032 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1033 	}
1034 
1035 	eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
1036 	if (attr->notification >= 0 && attr->notification < 32768) {
1037 		eap_aka_state(data, FAILURE);
1038 	} else if (attr->notification == EAP_SIM_SUCCESS &&
1039 		   data->state == RESULT_SUCCESS)
1040 		eap_aka_state(data, SUCCESS);
1041 	return eap_aka_response_notification(data, id, attr->notification);
1042 }
1043 
1044 
1045 static struct wpabuf * eap_aka_process_reauthentication(
1046 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1047 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1048 {
1049 	struct eap_sim_attrs eattr;
1050 	u8 *decrypted;
1051 
1052 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
1053 
1054 	if (attr->checkcode &&
1055 	    eap_aka_verify_checkcode(data, attr->checkcode,
1056 				     attr->checkcode_len)) {
1057 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
1058 			   "message");
1059 		return eap_aka_client_error(data, id,
1060 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1061 	}
1062 
1063 	if (data->reauth_id == NULL) {
1064 		wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
1065 			   "reauthentication, but no reauth_id available");
1066 		return eap_aka_client_error(data, id,
1067 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1068 	}
1069 
1070 	data->reauth = 1;
1071 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1072 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1073 			   "did not have valid AT_MAC");
1074 		return eap_aka_client_error(data, id,
1075 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1076 	}
1077 
1078 	if (attr->encr_data == NULL || attr->iv == NULL) {
1079 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1080 			   "message did not include encrypted data");
1081 		return eap_aka_client_error(data, id,
1082 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1083 	}
1084 
1085 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1086 				       attr->encr_data_len, attr->iv, &eattr,
1087 				       0);
1088 	if (decrypted == NULL) {
1089 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1090 			   "data from reauthentication message");
1091 		return eap_aka_client_error(data, id,
1092 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1093 	}
1094 
1095 	if (eattr.nonce_s == NULL || eattr.counter < 0) {
1096 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
1097 			   !eattr.nonce_s ? " AT_NONCE_S" : "",
1098 			   eattr.counter < 0 ? " AT_COUNTER" : "");
1099 		os_free(decrypted);
1100 		return eap_aka_client_error(data, id,
1101 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1102 	}
1103 
1104 	if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1105 		struct wpabuf *res;
1106 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
1107 			   "(%d <= %d)", eattr.counter, data->counter);
1108 		data->counter_too_small = eattr.counter;
1109 
1110 		/* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1111 		 * reauth_id must not be used to start a new reauthentication.
1112 		 * However, since it was used in the last EAP-Response-Identity
1113 		 * packet, it has to saved for the following fullauth to be
1114 		 * used in MK derivation. */
1115 		os_free(data->last_eap_identity);
1116 		data->last_eap_identity = data->reauth_id;
1117 		data->last_eap_identity_len = data->reauth_id_len;
1118 		data->reauth_id = NULL;
1119 		data->reauth_id_len = 0;
1120 
1121 		res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
1122 		os_free(decrypted);
1123 
1124 		return res;
1125 	}
1126 	data->counter = eattr.counter;
1127 
1128 	os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1129 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
1130 		    data->nonce_s, EAP_SIM_NONCE_S_LEN);
1131 
1132 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1133 		eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
1134 						 data->reauth_id,
1135 						 data->reauth_id_len,
1136 						 data->nonce_s,
1137 						 data->msk, data->emsk);
1138 	} else {
1139 		eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
1140 					   data->reauth_id_len,
1141 					   data->nonce_s, data->mk,
1142 					   data->msk, data->emsk);
1143 	}
1144 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1145 	eap_aka_learn_ids(sm, data, &eattr);
1146 
1147 	if (data->result_ind && attr->result_ind)
1148 		data->use_result_ind = 1;
1149 
1150 	if (data->state != FAILURE && data->state != RESULT_FAILURE) {
1151 		eap_aka_state(data, data->use_result_ind ?
1152 			      RESULT_SUCCESS : SUCCESS);
1153 	}
1154 
1155 	data->num_id_req = 0;
1156 	data->num_notification = 0;
1157 	if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
1158 		wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
1159 			   "fast reauths performed - force fullauth");
1160 		eap_aka_clear_identities(sm, data,
1161 					 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1162 	}
1163 	os_free(decrypted);
1164 	return eap_aka_response_reauth(data, id, 0, data->nonce_s);
1165 }
1166 
1167 
1168 static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
1169 				       struct eap_method_ret *ret,
1170 				       const struct wpabuf *reqData)
1171 {
1172 	struct eap_aka_data *data = priv;
1173 	const struct eap_hdr *req;
1174 	u8 subtype, id;
1175 	struct wpabuf *res;
1176 	const u8 *pos;
1177 	struct eap_sim_attrs attr;
1178 	size_t len;
1179 
1180 	wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
1181 	if (eap_get_config_identity(sm, &len) == NULL) {
1182 		wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
1183 		eap_sm_request_identity(sm);
1184 		ret->ignore = TRUE;
1185 		return NULL;
1186 	}
1187 
1188 	pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
1189 			       &len);
1190 	if (pos == NULL || len < 1) {
1191 		ret->ignore = TRUE;
1192 		return NULL;
1193 	}
1194 	req = wpabuf_head(reqData);
1195 	id = req->identifier;
1196 	len = be_to_host16(req->length);
1197 
1198 	ret->ignore = FALSE;
1199 	ret->methodState = METHOD_MAY_CONT;
1200 	ret->decision = DECISION_FAIL;
1201 	ret->allowNotifications = TRUE;
1202 
1203 	subtype = *pos++;
1204 	wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
1205 	pos += 2; /* Reserved */
1206 
1207 	if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
1208 			       data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1209 			       0)) {
1210 		res = eap_aka_client_error(data, id,
1211 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1212 		goto done;
1213 	}
1214 
1215 	switch (subtype) {
1216 	case EAP_AKA_SUBTYPE_IDENTITY:
1217 		res = eap_aka_process_identity(sm, data, id, reqData, &attr);
1218 		break;
1219 	case EAP_AKA_SUBTYPE_CHALLENGE:
1220 		res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
1221 		break;
1222 	case EAP_AKA_SUBTYPE_NOTIFICATION:
1223 		res = eap_aka_process_notification(sm, data, id, reqData,
1224 						   &attr);
1225 		break;
1226 	case EAP_AKA_SUBTYPE_REAUTHENTICATION:
1227 		res = eap_aka_process_reauthentication(sm, data, id, reqData,
1228 						       &attr);
1229 		break;
1230 	case EAP_AKA_SUBTYPE_CLIENT_ERROR:
1231 		wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
1232 		res = eap_aka_client_error(data, id,
1233 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1234 		break;
1235 	default:
1236 		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
1237 		res = eap_aka_client_error(data, id,
1238 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1239 		break;
1240 	}
1241 
1242 done:
1243 	if (data->state == FAILURE) {
1244 		ret->decision = DECISION_FAIL;
1245 		ret->methodState = METHOD_DONE;
1246 	} else if (data->state == SUCCESS) {
1247 		ret->decision = data->use_result_ind ?
1248 			DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1249 		/*
1250 		 * It is possible for the server to reply with AKA
1251 		 * Notification, so we must allow the method to continue and
1252 		 * not only accept EAP-Success at this point.
1253 		 */
1254 		ret->methodState = data->use_result_ind ?
1255 			METHOD_DONE : METHOD_MAY_CONT;
1256 	} else if (data->state == RESULT_FAILURE)
1257 		ret->methodState = METHOD_CONT;
1258 	else if (data->state == RESULT_SUCCESS)
1259 		ret->methodState = METHOD_CONT;
1260 
1261 	if (ret->methodState == METHOD_DONE) {
1262 		ret->allowNotifications = FALSE;
1263 	}
1264 
1265 	return res;
1266 }
1267 
1268 
1269 static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
1270 {
1271 	struct eap_aka_data *data = priv;
1272 	return data->pseudonym || data->reauth_id;
1273 }
1274 
1275 
1276 static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
1277 {
1278 	struct eap_aka_data *data = priv;
1279 	eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
1280 	data->prev_id = -1;
1281 	wpabuf_free(data->id_msgs);
1282 	data->id_msgs = NULL;
1283 	data->use_result_ind = 0;
1284 	data->kdf_negotiation = 0;
1285 }
1286 
1287 
1288 static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
1289 {
1290 	struct eap_aka_data *data = priv;
1291 	data->num_id_req = 0;
1292 	data->num_notification = 0;
1293 	eap_aka_state(data, CONTINUE);
1294 	return priv;
1295 }
1296 
1297 
1298 static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
1299 				       size_t *len)
1300 {
1301 	struct eap_aka_data *data = priv;
1302 
1303 	if (data->reauth_id) {
1304 		*len = data->reauth_id_len;
1305 		return data->reauth_id;
1306 	}
1307 
1308 	if (data->pseudonym) {
1309 		*len = data->pseudonym_len;
1310 		return data->pseudonym;
1311 	}
1312 
1313 	return NULL;
1314 }
1315 
1316 
1317 static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
1318 {
1319 	struct eap_aka_data *data = priv;
1320 	return data->state == SUCCESS;
1321 }
1322 
1323 
1324 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1325 {
1326 	struct eap_aka_data *data = priv;
1327 	u8 *key;
1328 
1329 	if (data->state != SUCCESS)
1330 		return NULL;
1331 
1332 	key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
1333 	if (key == NULL)
1334 		return NULL;
1335 
1336 	*len = EAP_SIM_KEYING_DATA_LEN;
1337 	os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
1338 
1339 	return key;
1340 }
1341 
1342 
1343 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1344 {
1345 	struct eap_aka_data *data = priv;
1346 	u8 *key;
1347 
1348 	if (data->state != SUCCESS)
1349 		return NULL;
1350 
1351 	key = os_malloc(EAP_EMSK_LEN);
1352 	if (key == NULL)
1353 		return NULL;
1354 
1355 	*len = EAP_EMSK_LEN;
1356 	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
1357 
1358 	return key;
1359 }
1360 
1361 
1362 int eap_peer_aka_register(void)
1363 {
1364 	struct eap_method *eap;
1365 	int ret;
1366 
1367 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1368 				    EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1369 	if (eap == NULL)
1370 		return -1;
1371 
1372 	eap->init = eap_aka_init;
1373 	eap->deinit = eap_aka_deinit;
1374 	eap->process = eap_aka_process;
1375 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1376 	eap->getKey = eap_aka_getKey;
1377 	eap->has_reauth_data = eap_aka_has_reauth_data;
1378 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1379 	eap->init_for_reauth = eap_aka_init_for_reauth;
1380 	eap->get_identity = eap_aka_get_identity;
1381 	eap->get_emsk = eap_aka_get_emsk;
1382 
1383 	ret = eap_peer_method_register(eap);
1384 	if (ret)
1385 		eap_peer_method_free(eap);
1386 	return ret;
1387 }
1388 
1389 
1390 #ifdef EAP_AKA_PRIME
1391 int eap_peer_aka_prime_register(void)
1392 {
1393 	struct eap_method *eap;
1394 	int ret;
1395 
1396 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1397 				    EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1398 				    "AKA'");
1399 	if (eap == NULL)
1400 		return -1;
1401 
1402 	eap->init = eap_aka_prime_init;
1403 	eap->deinit = eap_aka_deinit;
1404 	eap->process = eap_aka_process;
1405 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1406 	eap->getKey = eap_aka_getKey;
1407 	eap->has_reauth_data = eap_aka_has_reauth_data;
1408 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1409 	eap->init_for_reauth = eap_aka_init_for_reauth;
1410 	eap->get_identity = eap_aka_get_identity;
1411 	eap->get_emsk = eap_aka_get_emsk;
1412 
1413 	ret = eap_peer_method_register(eap);
1414 	if (ret)
1415 		eap_peer_method_free(eap);
1416 
1417 	return ret;
1418 }
1419 #endif /* EAP_AKA_PRIME */
1420