xref: /freebsd/contrib/wpa/src/eap_peer/eap_aka.c (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
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 	u8 reauth_mac[EAP_SIM_MAC_LEN];
35 
36 	int num_id_req, num_notification;
37 	u8 *pseudonym;
38 	size_t pseudonym_len;
39 	u8 *reauth_id;
40 	size_t reauth_id_len;
41 	int reauth;
42 	unsigned int counter, counter_too_small;
43 	u8 *last_eap_identity;
44 	size_t last_eap_identity_len;
45 	enum {
46 		CONTINUE, RESULT_SUCCESS, SUCCESS, FAILURE
47 	} state;
48 
49 	struct wpabuf *id_msgs;
50 	int prev_id;
51 	int result_ind, use_result_ind;
52 	int use_pseudonym;
53 	u8 eap_method;
54 	u8 *network_name;
55 	size_t network_name_len;
56 	u16 kdf;
57 	int kdf_negotiation;
58 	u16 last_kdf_attrs[EAP_AKA_PRIME_KDF_MAX];
59 	size_t last_kdf_count;
60 	int error_code;
61 };
62 
63 
64 #ifndef CONFIG_NO_STDOUT_DEBUG
65 static const char * eap_aka_state_txt(int state)
66 {
67 	switch (state) {
68 	case CONTINUE:
69 		return "CONTINUE";
70 	case RESULT_SUCCESS:
71 		return "RESULT_SUCCESS";
72 	case SUCCESS:
73 		return "SUCCESS";
74 	case FAILURE:
75 		return "FAILURE";
76 	default:
77 		return "?";
78 	}
79 }
80 #endif /* CONFIG_NO_STDOUT_DEBUG */
81 
82 
83 static void eap_aka_state(struct eap_aka_data *data, int state)
84 {
85 	wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
86 		   eap_aka_state_txt(data->state),
87 		   eap_aka_state_txt(state));
88 	data->state = state;
89 }
90 
91 
92 static void * eap_aka_init(struct eap_sm *sm)
93 {
94 	struct eap_aka_data *data;
95 	const char *phase1 = eap_get_config_phase1(sm);
96 	struct eap_peer_config *config = eap_get_config(sm);
97 
98 	data = os_zalloc(sizeof(*data));
99 	if (data == NULL)
100 		return NULL;
101 
102 	data->eap_method = EAP_TYPE_AKA;
103 
104 	/* Zero is a valid error code, so we need to initialize */
105 	data->error_code = NO_EAP_METHOD_ERROR;
106 
107 	eap_aka_state(data, CONTINUE);
108 	data->prev_id = -1;
109 
110 	data->result_ind = phase1 && os_strstr(phase1, "result_ind=1") != NULL;
111 
112 	data->use_pseudonym = !sm->init_phase2;
113 	if (config && config->anonymous_identity && data->use_pseudonym) {
114 		data->pseudonym = os_malloc(config->anonymous_identity_len);
115 		if (data->pseudonym) {
116 			os_memcpy(data->pseudonym, config->anonymous_identity,
117 				  config->anonymous_identity_len);
118 			data->pseudonym_len = config->anonymous_identity_len;
119 		}
120 	}
121 
122 	return data;
123 }
124 
125 
126 #ifdef EAP_AKA_PRIME
127 static void * eap_aka_prime_init(struct eap_sm *sm)
128 {
129 	struct eap_aka_data *data = eap_aka_init(sm);
130 	if (data == NULL)
131 		return NULL;
132 	data->eap_method = EAP_TYPE_AKA_PRIME;
133 	return data;
134 }
135 #endif /* EAP_AKA_PRIME */
136 
137 
138 static void eap_aka_clear_keys(struct eap_aka_data *data, int reauth)
139 {
140 	if (!reauth) {
141 		os_memset(data->mk, 0, EAP_SIM_MK_LEN);
142 		os_memset(data->k_aut, 0, EAP_AKA_PRIME_K_AUT_LEN);
143 		os_memset(data->k_encr, 0, EAP_SIM_K_ENCR_LEN);
144 		os_memset(data->k_re, 0, EAP_AKA_PRIME_K_RE_LEN);
145 	}
146 	os_memset(data->msk, 0, EAP_SIM_KEYING_DATA_LEN);
147 	os_memset(data->emsk, 0, EAP_EMSK_LEN);
148 	os_memset(data->autn, 0, EAP_AKA_AUTN_LEN);
149 	os_memset(data->auts, 0, EAP_AKA_AUTS_LEN);
150 }
151 
152 
153 static void eap_aka_deinit(struct eap_sm *sm, void *priv)
154 {
155 	struct eap_aka_data *data = priv;
156 	if (data) {
157 		os_free(data->pseudonym);
158 		os_free(data->reauth_id);
159 		os_free(data->last_eap_identity);
160 		wpabuf_free(data->id_msgs);
161 		os_free(data->network_name);
162 		eap_aka_clear_keys(data, 0);
163 		os_free(data);
164 	}
165 }
166 
167 
168 static int eap_aka_ext_sim_req(struct eap_sm *sm, struct eap_aka_data *data)
169 {
170 	char req[200], *pos, *end;
171 
172 	wpa_printf(MSG_DEBUG, "EAP-AKA: Use external USIM processing");
173 	pos = req;
174 	end = pos + sizeof(req);
175 	pos += os_snprintf(pos, end - pos, "UMTS-AUTH");
176 	pos += os_snprintf(pos, end - pos, ":");
177 	pos += wpa_snprintf_hex(pos, end - pos, data->rand, EAP_AKA_RAND_LEN);
178 	pos += os_snprintf(pos, end - pos, ":");
179 	wpa_snprintf_hex(pos, end - pos, data->autn, EAP_AKA_AUTN_LEN);
180 
181 	eap_sm_request_sim(sm, req);
182 	return 1;
183 }
184 
185 
186 static int eap_aka_ext_sim_result(struct eap_sm *sm, struct eap_aka_data *data,
187 				  struct eap_peer_config *conf)
188 {
189 	char *resp, *pos;
190 
191 	wpa_printf(MSG_DEBUG,
192 		   "EAP-AKA: Use result from external USIM processing");
193 
194 	resp = conf->external_sim_resp;
195 	conf->external_sim_resp = NULL;
196 
197 	if (os_strncmp(resp, "UMTS-AUTS:", 10) == 0) {
198 		pos = resp + 10;
199 		if (hexstr2bin(pos, data->auts, EAP_AKA_AUTS_LEN) < 0)
200 			goto invalid;
201 		wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: AUTS", data->auts,
202 				EAP_AKA_AUTS_LEN);
203 		os_free(resp);
204 		return -2;
205 	}
206 
207 	if (os_strncmp(resp, "UMTS-AUTH:", 10) != 0) {
208 		wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized external USIM processing response");
209 		os_free(resp);
210 		return -1;
211 	}
212 
213 	pos = resp + 10;
214 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: RAND", data->rand, EAP_AKA_RAND_LEN);
215 
216 	if (hexstr2bin(pos, data->ik, EAP_AKA_IK_LEN) < 0)
217 		goto invalid;
218 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", data->ik, EAP_AKA_IK_LEN);
219 	pos += EAP_AKA_IK_LEN * 2;
220 	if (*pos != ':')
221 		goto invalid;
222 	pos++;
223 
224 	if (hexstr2bin(pos, data->ck, EAP_AKA_CK_LEN) < 0)
225 		goto invalid;
226 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", data->ck, EAP_AKA_CK_LEN);
227 	pos += EAP_AKA_CK_LEN * 2;
228 	if (*pos != ':')
229 		goto invalid;
230 	pos++;
231 
232 	data->res_len = os_strlen(pos) / 2;
233 	if (data->res_len > EAP_AKA_RES_MAX_LEN) {
234 		data->res_len = 0;
235 		goto invalid;
236 	}
237 	if (hexstr2bin(pos, data->res, data->res_len) < 0)
238 		goto invalid;
239 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: RES", data->res, data->res_len);
240 
241 	os_free(resp);
242 	return 0;
243 
244 invalid:
245 	wpa_printf(MSG_DEBUG, "EAP-AKA: Invalid external USIM processing UMTS-AUTH response");
246 	os_free(resp);
247 	return -1;
248 }
249 
250 
251 static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data)
252 {
253 	struct eap_peer_config *conf;
254 
255 	wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm");
256 
257 	conf = eap_get_config(sm);
258 	if (conf == NULL)
259 		return -1;
260 
261 	if (sm->external_sim) {
262 		if (conf->external_sim_resp)
263 			return eap_aka_ext_sim_result(sm, data, conf);
264 		else
265 			return eap_aka_ext_sim_req(sm, data);
266 	}
267 
268 	if (conf->pcsc) {
269 		return scard_umts_auth(sm->scard_ctx, data->rand,
270 				       data->autn, data->res, &data->res_len,
271 				       data->ik, data->ck, data->auts);
272 	}
273 
274 #ifdef CONFIG_USIM_SIMULATOR
275 	if (conf->password) {
276 		u8 opc[16], k[16], sqn[6];
277 		const char *pos;
278 		wpa_printf(MSG_DEBUG, "EAP-AKA: Use internal Milenage "
279 			   "implementation for UMTS authentication");
280 		if (conf->password_len < 78) {
281 			wpa_printf(MSG_DEBUG, "EAP-AKA: invalid Milenage "
282 				   "password");
283 			return -1;
284 		}
285 		pos = (const char *) conf->password;
286 		if (hexstr2bin(pos, k, 16))
287 			return -1;
288 		pos += 32;
289 		if (*pos != ':')
290 			return -1;
291 		pos++;
292 
293 		if (hexstr2bin(pos, opc, 16))
294 			return -1;
295 		pos += 32;
296 		if (*pos != ':')
297 			return -1;
298 		pos++;
299 
300 		if (hexstr2bin(pos, sqn, 6))
301 			return -1;
302 
303 		return milenage_check(opc, k, sqn, data->rand, data->autn,
304 				      data->ik, data->ck,
305 				      data->res, &data->res_len, data->auts);
306 	}
307 #endif /* CONFIG_USIM_SIMULATOR */
308 
309 #ifdef CONFIG_USIM_HARDCODED
310 	wpa_printf(MSG_DEBUG, "EAP-AKA: Use hardcoded Kc and SRES values for "
311 		   "testing");
312 
313 	/* These hardcoded Kc and SRES values are used for testing.
314 	 * Could consider making them configurable. */
315 	os_memset(data->res, '2', EAP_AKA_RES_MAX_LEN);
316 	data->res_len = EAP_AKA_RES_MAX_LEN;
317 	os_memset(data->ik, '3', EAP_AKA_IK_LEN);
318 	os_memset(data->ck, '4', EAP_AKA_CK_LEN);
319 	{
320 		u8 autn[EAP_AKA_AUTN_LEN];
321 		os_memset(autn, '1', EAP_AKA_AUTN_LEN);
322 		if (os_memcmp_const(autn, data->autn, EAP_AKA_AUTN_LEN) != 0) {
323 			wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match "
324 				   "with expected value");
325 			return -1;
326 		}
327 	}
328 #if 0
329 	{
330 		static int test_resync = 1;
331 		if (test_resync) {
332 			/* Test Resynchronization */
333 			test_resync = 0;
334 			return -2;
335 		}
336 	}
337 #endif
338 	return 0;
339 
340 #else /* CONFIG_USIM_HARDCODED */
341 
342 	wpa_printf(MSG_DEBUG, "EAP-AKA: No UMTS authentication algorithm "
343 		   "enabled");
344 	return -1;
345 
346 #endif /* CONFIG_USIM_HARDCODED */
347 }
348 
349 
350 #define CLEAR_PSEUDONYM	0x01
351 #define CLEAR_REAUTH_ID	0x02
352 #define CLEAR_EAP_ID	0x04
353 
354 static void eap_aka_clear_identities(struct eap_sm *sm,
355 				     struct eap_aka_data *data, int id)
356 {
357 	if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
358 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old pseudonym");
359 		os_free(data->pseudonym);
360 		data->pseudonym = NULL;
361 		data->pseudonym_len = 0;
362 		if (data->use_pseudonym)
363 			eap_set_anon_id(sm, NULL, 0);
364 	}
365 	if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
366 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old reauth_id");
367 		os_free(data->reauth_id);
368 		data->reauth_id = NULL;
369 		data->reauth_id_len = 0;
370 	}
371 	if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
372 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old eap_id");
373 		os_free(data->last_eap_identity);
374 		data->last_eap_identity = NULL;
375 		data->last_eap_identity_len = 0;
376 	}
377 }
378 
379 
380 static int eap_aka_learn_ids(struct eap_sm *sm, struct eap_aka_data *data,
381 			     struct eap_sim_attrs *attr)
382 {
383 	if (attr->next_pseudonym) {
384 		const u8 *identity = NULL;
385 		size_t identity_len = 0;
386 		const u8 *realm = NULL;
387 		size_t realm_len = 0;
388 
389 		wpa_hexdump_ascii(MSG_DEBUG,
390 				  "EAP-AKA: (encr) AT_NEXT_PSEUDONYM",
391 				  attr->next_pseudonym,
392 				  attr->next_pseudonym_len);
393 		os_free(data->pseudonym);
394 		/* Look for the realm of the permanent identity */
395 		identity = eap_get_config_identity(sm, &identity_len);
396 		if (identity) {
397 			for (realm = identity, realm_len = identity_len;
398 			     realm_len > 0; realm_len--, realm++) {
399 				if (*realm == '@')
400 					break;
401 			}
402 		}
403 		data->pseudonym = os_malloc(attr->next_pseudonym_len +
404 					    realm_len);
405 		if (data->pseudonym == NULL) {
406 			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
407 				   "next pseudonym");
408 			data->pseudonym_len = 0;
409 			return -1;
410 		}
411 		os_memcpy(data->pseudonym, attr->next_pseudonym,
412 			  attr->next_pseudonym_len);
413 		if (realm_len) {
414 			os_memcpy(data->pseudonym + attr->next_pseudonym_len,
415 				  realm, realm_len);
416 		}
417 		data->pseudonym_len = attr->next_pseudonym_len + realm_len;
418 		if (data->use_pseudonym)
419 			eap_set_anon_id(sm, data->pseudonym,
420 					data->pseudonym_len);
421 	}
422 
423 	if (attr->next_reauth_id) {
424 		os_free(data->reauth_id);
425 		data->reauth_id = os_memdup(attr->next_reauth_id,
426 					    attr->next_reauth_id_len);
427 		if (data->reauth_id == NULL) {
428 			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
429 				   "next reauth_id");
430 			data->reauth_id_len = 0;
431 			return -1;
432 		}
433 		data->reauth_id_len = attr->next_reauth_id_len;
434 		wpa_hexdump_ascii(MSG_DEBUG,
435 				  "EAP-AKA: (encr) AT_NEXT_REAUTH_ID",
436 				  data->reauth_id,
437 				  data->reauth_id_len);
438 	}
439 
440 	return 0;
441 }
442 
443 
444 static int eap_aka_add_id_msg(struct eap_aka_data *data,
445 			      const struct wpabuf *msg1,
446 			      const struct wpabuf *msg2)
447 {
448 	size_t len;
449 
450 	if (!msg1)
451 		return -1;
452 	len = wpabuf_len(msg1);
453 	if (msg2)
454 		len += wpabuf_len(msg2);
455 
456 	if (!data->id_msgs) {
457 		data->id_msgs = wpabuf_alloc(len);
458 		if (!data->id_msgs)
459 			return -1;
460 	} else if (wpabuf_resize(&data->id_msgs, len) < 0) {
461 		return -1;
462 	}
463 
464 	wpabuf_put_buf(data->id_msgs, msg1);
465 	if (msg2)
466 		wpabuf_put_buf(data->id_msgs, msg2);
467 
468 	return 0;
469 }
470 
471 
472 static void eap_aka_add_checkcode(struct eap_aka_data *data,
473 				  struct eap_sim_msg *msg)
474 {
475 	const u8 *addr;
476 	size_t len;
477 	u8 hash[SHA256_MAC_LEN];
478 
479 	wpa_printf(MSG_DEBUG, "   AT_CHECKCODE");
480 
481 	if (data->id_msgs == NULL) {
482 		/*
483 		 * No EAP-AKA/Identity packets were exchanged - send empty
484 		 * checkcode.
485 		 */
486 		eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
487 		return;
488 	}
489 
490 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
491 	addr = wpabuf_head(data->id_msgs);
492 	len = wpabuf_len(data->id_msgs);
493 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
494 #ifdef EAP_AKA_PRIME
495 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
496 		sha256_vector(1, &addr, &len, hash);
497 	else
498 #endif /* EAP_AKA_PRIME */
499 		sha1_vector(1, &addr, &len, hash);
500 
501 	eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
502 			data->eap_method == EAP_TYPE_AKA_PRIME ?
503 			EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
504 }
505 
506 
507 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
508 				    const u8 *checkcode, size_t checkcode_len)
509 {
510 	const u8 *addr;
511 	size_t len;
512 	u8 hash[SHA256_MAC_LEN];
513 	size_t hash_len;
514 
515 	if (checkcode == NULL)
516 		return -1;
517 
518 	if (data->id_msgs == NULL) {
519 		if (checkcode_len != 0) {
520 			wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
521 				   "indicates that AKA/Identity messages were "
522 				   "used, but they were not");
523 			return -1;
524 		}
525 		return 0;
526 	}
527 
528 	hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
529 		EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
530 
531 	if (checkcode_len != hash_len) {
532 		wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
533 			   "indicates that AKA/Identity message were not "
534 			   "used, but they were");
535 		return -1;
536 	}
537 
538 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
539 	addr = wpabuf_head(data->id_msgs);
540 	len = wpabuf_len(data->id_msgs);
541 #ifdef EAP_AKA_PRIME
542 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
543 		sha256_vector(1, &addr, &len, hash);
544 	else
545 #endif /* EAP_AKA_PRIME */
546 		sha1_vector(1, &addr, &len, hash);
547 
548 	if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
549 		wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
550 		return -1;
551 	}
552 
553 	return 0;
554 }
555 
556 
557 static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
558 					    int err)
559 {
560 	struct eap_sim_msg *msg;
561 
562 	eap_aka_state(data, FAILURE);
563 	data->num_id_req = 0;
564 	data->num_notification = 0;
565 
566 	wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
567 		   err);
568 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
569 			       EAP_AKA_SUBTYPE_CLIENT_ERROR);
570 	eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
571 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
572 }
573 
574 
575 static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
576 						     u8 id)
577 {
578 	struct eap_sim_msg *msg;
579 
580 	eap_aka_state(data, FAILURE);
581 	data->num_id_req = 0;
582 	data->num_notification = 0;
583 
584 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
585 		   "(id=%d)", id);
586 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
587 			       EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
588 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
589 }
590 
591 
592 static struct wpabuf * eap_aka_synchronization_failure(
593 	struct eap_aka_data *data, u8 id, struct eap_sim_attrs *attr)
594 {
595 	struct eap_sim_msg *msg;
596 
597 	data->num_id_req = 0;
598 	data->num_notification = 0;
599 
600 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
601 		   "(id=%d)", id);
602 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
603 			       EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
604 	wpa_printf(MSG_DEBUG, "   AT_AUTS");
605 	eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
606 			     EAP_AKA_AUTS_LEN);
607 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
608 		size_t i;
609 
610 		for (i = 0; i < attr->kdf_count; i++) {
611 			wpa_printf(MSG_DEBUG, "   AT_KDF");
612 			eap_sim_msg_add(msg, EAP_SIM_AT_KDF, attr->kdf[i],
613 					NULL, 0);
614 		}
615 	}
616 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
617 }
618 
619 
620 static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
621 						 struct eap_aka_data *data,
622 						 u8 id,
623 						 enum eap_sim_id_req id_req)
624 {
625 	const u8 *identity = NULL;
626 	size_t identity_len = 0;
627 	struct eap_sim_msg *msg;
628 
629 	data->reauth = 0;
630 	if (id_req == ANY_ID && data->reauth_id) {
631 		identity = data->reauth_id;
632 		identity_len = data->reauth_id_len;
633 		data->reauth = 1;
634 	} else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
635 		   data->pseudonym &&
636 		   !eap_sim_anonymous_username(data->pseudonym,
637 					       data->pseudonym_len)) {
638 		identity = data->pseudonym;
639 		identity_len = data->pseudonym_len;
640 		eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
641 	} else if (id_req != NO_ID_REQ) {
642 		identity = eap_get_config_identity(sm, &identity_len);
643 		if (identity) {
644 			int ids = CLEAR_PSEUDONYM | CLEAR_REAUTH_ID;
645 
646 			if (data->pseudonym &&
647 			    eap_sim_anonymous_username(data->pseudonym,
648 						       data->pseudonym_len))
649 				ids &= ~CLEAR_PSEUDONYM;
650 			eap_aka_clear_identities(sm, data, ids);
651 		}
652 	}
653 	if (id_req != NO_ID_REQ)
654 		eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
655 
656 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
657 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
658 			       EAP_AKA_SUBTYPE_IDENTITY);
659 
660 	if (identity) {
661 		wpa_hexdump_ascii(MSG_DEBUG, "   AT_IDENTITY",
662 				  identity, identity_len);
663 		eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
664 				identity, identity_len);
665 	}
666 
667 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
668 }
669 
670 
671 static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
672 						  u8 id)
673 {
674 	struct eap_sim_msg *msg;
675 
676 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
677 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
678 			       EAP_AKA_SUBTYPE_CHALLENGE);
679 	wpa_printf(MSG_DEBUG, "   AT_RES");
680 	eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
681 			data->res, data->res_len);
682 	eap_aka_add_checkcode(data, msg);
683 	if (data->use_result_ind) {
684 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
685 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
686 	}
687 	wpa_printf(MSG_DEBUG, "   AT_MAC");
688 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
689 	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, (u8 *) "",
690 				  0);
691 }
692 
693 
694 static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
695 					       u8 id, int counter_too_small,
696 					       const u8 *nonce_s)
697 {
698 	struct eap_sim_msg *msg;
699 	unsigned int counter;
700 
701 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
702 		   id);
703 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
704 			       EAP_AKA_SUBTYPE_REAUTHENTICATION);
705 	wpa_printf(MSG_DEBUG, "   AT_IV");
706 	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
707 	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
708 
709 	if (counter_too_small) {
710 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER_TOO_SMALL");
711 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
712 		counter = data->counter_too_small;
713 	} else
714 		counter = data->counter;
715 
716 	wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", counter);
717 	eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
718 
719 	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
720 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
721 			   "AT_ENCR_DATA");
722 		eap_sim_msg_free(msg);
723 		return NULL;
724 	}
725 	eap_aka_add_checkcode(data, msg);
726 	if (data->use_result_ind) {
727 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
728 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
729 	}
730 	wpa_printf(MSG_DEBUG, "   AT_MAC");
731 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
732 	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, nonce_s,
733 				  EAP_SIM_NONCE_S_LEN);
734 }
735 
736 
737 static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
738 						     u8 id, u16 notification)
739 {
740 	struct eap_sim_msg *msg;
741 	u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
742 
743 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
744 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
745 			       EAP_AKA_SUBTYPE_NOTIFICATION);
746 	if (k_aut && data->reauth) {
747 		wpa_printf(MSG_DEBUG, "   AT_IV");
748 		wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
749 		eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
750 					   EAP_SIM_AT_ENCR_DATA);
751 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", data->counter);
752 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
753 				NULL, 0);
754 		if (eap_sim_msg_add_encr_end(msg, data->k_encr,
755 					     EAP_SIM_AT_PADDING)) {
756 			wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
757 				   "AT_ENCR_DATA");
758 			eap_sim_msg_free(msg);
759 			return NULL;
760 		}
761 	}
762 	if (k_aut) {
763 		wpa_printf(MSG_DEBUG, "   AT_MAC");
764 		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
765 	}
766 	return eap_sim_msg_finish(msg, data->eap_method, k_aut, (u8 *) "", 0);
767 }
768 
769 
770 static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
771 						struct eap_aka_data *data,
772 						u8 id,
773 						const struct wpabuf *reqData,
774 						struct eap_sim_attrs *attr)
775 {
776 	int id_error;
777 	struct wpabuf *buf;
778 
779 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
780 
781 	id_error = 0;
782 	switch (attr->id_req) {
783 	case NO_ID_REQ:
784 		break;
785 	case ANY_ID:
786 		if (data->num_id_req > 0)
787 			id_error++;
788 		data->num_id_req++;
789 		break;
790 	case FULLAUTH_ID:
791 		if (data->num_id_req > 1)
792 			id_error++;
793 		data->num_id_req++;
794 		break;
795 	case PERMANENT_ID:
796 		if (data->num_id_req > 2)
797 			id_error++;
798 		data->num_id_req++;
799 		break;
800 	}
801 	if (id_error) {
802 		wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
803 			   "used within one authentication");
804 		return eap_aka_client_error(data, id,
805 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
806 	}
807 
808 	buf = eap_aka_response_identity(sm, data, id, attr->id_req);
809 
810 	if (data->prev_id != id) {
811 		if (eap_aka_add_id_msg(data, reqData, buf) < 0) {
812 			wpa_printf(MSG_INFO,
813 				   "EAP-AKA: Failed to store ID messages");
814 			wpabuf_free(buf);
815 			return eap_aka_client_error(
816 				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
817 		}
818 		data->prev_id = id;
819 	}
820 
821 	return buf;
822 }
823 
824 
825 static int eap_aka_verify_mac(struct eap_aka_data *data,
826 			      const struct wpabuf *req,
827 			      const u8 *mac, const u8 *extra,
828 			      size_t extra_len)
829 {
830 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
831 		return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
832 						 extra_len);
833 	return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
834 }
835 
836 
837 #ifdef EAP_AKA_PRIME
838 static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
839 						u8 id, u16 kdf)
840 {
841 	struct eap_sim_msg *msg;
842 
843 	data->kdf_negotiation = 1;
844 	data->kdf = kdf;
845 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
846 		   "select)", id);
847 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
848 			       EAP_AKA_SUBTYPE_CHALLENGE);
849 	wpa_printf(MSG_DEBUG, "   AT_KDF");
850 	eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
851 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
852 }
853 
854 
855 static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
856 					     u8 id, struct eap_sim_attrs *attr)
857 {
858 	size_t i;
859 
860 	for (i = 0; i < attr->kdf_count; i++) {
861 		if (attr->kdf[i] == EAP_AKA_PRIME_KDF) {
862 			os_memcpy(data->last_kdf_attrs, attr->kdf,
863 				  sizeof(u16) * attr->kdf_count);
864 			data->last_kdf_count = attr->kdf_count;
865 			return eap_aka_prime_kdf_select(data, id,
866 							EAP_AKA_PRIME_KDF);
867 		}
868 	}
869 
870 	/* No matching KDF found - fail authentication as if AUTN had been
871 	 * incorrect */
872 	return eap_aka_authentication_reject(data, id);
873 }
874 
875 
876 static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
877 				   struct eap_sim_attrs *attr)
878 {
879 	size_t i, j;
880 
881 	if (attr->kdf_count == 0)
882 		return 0;
883 
884 	/* The only allowed (and required) duplication of a KDF is the addition
885 	 * of the selected KDF into the beginning of the list. */
886 
887 	if (data->kdf_negotiation) {
888 		/* When the peer receives the new EAP-Request/AKA'-Challenge
889 		 * message, must check only requested change occurred in the
890 		 * list of AT_KDF attributes. If there are any other changes,
891 		 * the peer must behave like the case that AT_MAC had been
892 		 * incorrect and authentication is failed. These are defined in
893 		 * EAP-AKA' specification RFC 5448, Section 3.2. */
894 		if (attr->kdf[0] != data->kdf) {
895 			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
896 				   "accept the selected KDF");
897 			return -1;
898 		}
899 
900 		if (attr->kdf_count > EAP_AKA_PRIME_KDF_MAX ||
901 		    attr->kdf_count != data->last_kdf_count + 1) {
902 			wpa_printf(MSG_WARNING,
903 				   "EAP-AKA': The length of KDF attributes is wrong");
904 			return -1;
905 		}
906 
907 		for (i = 1; i < attr->kdf_count; i++) {
908 			if (attr->kdf[i] != data->last_kdf_attrs[i - 1]) {
909 				wpa_printf(MSG_WARNING,
910 					   "EAP-AKA': The KDF attributes except selected KDF are not same as original one");
911 				return -1;
912 			}
913 		}
914 	}
915 
916 	for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
917 		for (j = i + 1; j < attr->kdf_count; j++) {
918 			if (attr->kdf[i] == attr->kdf[j]) {
919 				wpa_printf(MSG_WARNING, "EAP-AKA': The server "
920 					   "included a duplicated KDF");
921 				return 0;
922 			}
923 		}
924 	}
925 
926 	return 1;
927 }
928 #endif /* EAP_AKA_PRIME */
929 
930 
931 static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
932 						 struct eap_aka_data *data,
933 						 u8 id,
934 						 const struct wpabuf *reqData,
935 						 struct eap_sim_attrs *attr)
936 {
937 	const u8 *identity;
938 	size_t identity_len;
939 	int res;
940 	struct eap_sim_attrs eattr;
941 
942 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
943 
944 	if (attr->checkcode &&
945 	    eap_aka_verify_checkcode(data, attr->checkcode,
946 				     attr->checkcode_len)) {
947 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
948 			   "message");
949 #ifdef TEST_FUZZ
950 		wpa_printf(MSG_INFO,
951 			   "TEST: Ignore AT_CHECKCODE mismatch for fuzz testing");
952 #else /* TEST_FUZZ */
953 		return eap_aka_client_error(data, id,
954 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
955 #endif /* TEST_FUZZ */
956 	}
957 
958 #ifdef EAP_AKA_PRIME
959 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
960 		if (!attr->kdf_input || attr->kdf_input_len == 0) {
961 			wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
962 				   "did not include non-empty AT_KDF_INPUT");
963 			/* Fail authentication as if AUTN had been incorrect */
964 			return eap_aka_authentication_reject(data, id);
965 		}
966 		os_free(data->network_name);
967 		data->network_name = os_memdup(attr->kdf_input,
968 					       attr->kdf_input_len);
969 		if (data->network_name == NULL) {
970 			wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
971 				   "storing Network Name");
972 			return eap_aka_authentication_reject(data, id);
973 		}
974 		data->network_name_len = attr->kdf_input_len;
975 		wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
976 				  "(AT_KDF_INPUT)",
977 				  data->network_name, data->network_name_len);
978 		/* TODO: check Network Name per 3GPP.33.402 */
979 
980 		res = eap_aka_prime_kdf_valid(data, attr);
981 		if (res == 0)
982 			return eap_aka_authentication_reject(data, id);
983 		else if (res == -1)
984 			return eap_aka_client_error(
985 				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
986 
987 		if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
988 			return eap_aka_prime_kdf_neg(data, id, attr);
989 
990 		data->kdf = EAP_AKA_PRIME_KDF;
991 		wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
992 	}
993 
994 	if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
995 		u16 flags = WPA_GET_BE16(attr->bidding);
996 		if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
997 		    eap_allowed_method(sm, EAP_VENDOR_IETF,
998 				       EAP_TYPE_AKA_PRIME)) {
999 			wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
1000 				   "AKA' to AKA detected");
1001 			/* Fail authentication as if AUTN had been incorrect */
1002 			return eap_aka_authentication_reject(data, id);
1003 		}
1004 	}
1005 #endif /* EAP_AKA_PRIME */
1006 
1007 	data->reauth = 0;
1008 	if (!attr->mac || !attr->rand || !attr->autn) {
1009 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
1010 			   "did not include%s%s%s",
1011 			   !attr->mac ? " AT_MAC" : "",
1012 			   !attr->rand ? " AT_RAND" : "",
1013 			   !attr->autn ? " AT_AUTN" : "");
1014 		return eap_aka_client_error(data, id,
1015 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1016 	}
1017 	os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
1018 	os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
1019 
1020 	res = eap_aka_umts_auth(sm, data);
1021 	if (res == -1) {
1022 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
1023 			   "failed (AUTN)");
1024 		return eap_aka_authentication_reject(data, id);
1025 	} else if (res == -2) {
1026 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
1027 			   "failed (AUTN seq# -> AUTS)");
1028 		return eap_aka_synchronization_failure(data, id, attr);
1029 	} else if (res > 0) {
1030 		wpa_printf(MSG_DEBUG, "EAP-AKA: Wait for external USIM processing");
1031 		return NULL;
1032 	} else if (res) {
1033 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
1034 		return eap_aka_client_error(data, id,
1035 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1036 	}
1037 #ifdef EAP_AKA_PRIME
1038 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1039 		/* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
1040 		 * needed 6-octet SQN ^ AK for CK',IK' derivation */
1041 		u16 amf = WPA_GET_BE16(data->autn + 6);
1042 		if (!(amf & 0x8000)) {
1043 			wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
1044 				   "not set (AMF=0x%4x)", amf);
1045 			return eap_aka_authentication_reject(data, id);
1046 		}
1047 		eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
1048 						 data->autn,
1049 						 data->network_name,
1050 						 data->network_name_len);
1051 	}
1052 #endif /* EAP_AKA_PRIME */
1053 	if (data->last_eap_identity) {
1054 		identity = data->last_eap_identity;
1055 		identity_len = data->last_eap_identity_len;
1056 	} else if (data->pseudonym &&
1057 		   !eap_sim_anonymous_username(data->pseudonym,
1058 					       data->pseudonym_len)) {
1059 		identity = data->pseudonym;
1060 		identity_len = data->pseudonym_len;
1061 	} else {
1062 		struct eap_peer_config *config;
1063 
1064 		config = eap_get_config(sm);
1065 		if (config && config->imsi_identity) {
1066 			identity = config->imsi_identity;
1067 			identity_len = config->imsi_identity_len;
1068 		} else {
1069 			identity = eap_get_config_identity(sm, &identity_len);
1070 		}
1071 	}
1072 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
1073 			  "derivation", identity, identity_len);
1074 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1075 		eap_aka_prime_derive_keys(identity, identity_len, data->ik,
1076 					  data->ck, data->k_encr, data->k_aut,
1077 					  data->k_re, data->msk, data->emsk);
1078 	} else {
1079 		eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
1080 				  data->mk);
1081 		eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
1082 				    data->msk, data->emsk);
1083 	}
1084 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1085 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
1086 			   "used invalid AT_MAC");
1087 #ifdef TEST_FUZZ
1088 		wpa_printf(MSG_INFO,
1089 			   "TEST: Ignore AT_MAC mismatch for fuzz testing");
1090 #else /* TEST_FUZZ */
1091 		return eap_aka_client_error(data, id,
1092 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1093 #endif /* TEST_FUZZ */
1094 	}
1095 
1096 	/* Old reauthentication identity must not be used anymore. In
1097 	 * other words, if no new identities are received, full
1098 	 * authentication will be used on next reauthentication (using
1099 	 * pseudonym identity or permanent identity). */
1100 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1101 
1102 	if (attr->encr_data) {
1103 		u8 *decrypted;
1104 		decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1105 					       attr->encr_data_len, attr->iv,
1106 					       &eattr, 0);
1107 		if (decrypted == NULL) {
1108 			return eap_aka_client_error(
1109 				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1110 		}
1111 		eap_aka_learn_ids(sm, data, &eattr);
1112 		os_free(decrypted);
1113 	}
1114 
1115 	if (data->result_ind && attr->result_ind)
1116 		data->use_result_ind = 1;
1117 
1118 	if (data->state != FAILURE) {
1119 		eap_aka_state(data, data->use_result_ind ?
1120 			      RESULT_SUCCESS : SUCCESS);
1121 	}
1122 
1123 	data->num_id_req = 0;
1124 	data->num_notification = 0;
1125 	/* RFC 4187 specifies that counter is initialized to one after
1126 	 * fullauth, but initializing it to zero makes it easier to implement
1127 	 * reauth verification. */
1128 	data->counter = 0;
1129 	return eap_aka_response_challenge(data, id);
1130 }
1131 
1132 
1133 static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
1134 					       struct eap_sim_attrs *attr)
1135 {
1136 	struct eap_sim_attrs eattr;
1137 	u8 *decrypted;
1138 
1139 	if (attr->encr_data == NULL || attr->iv == NULL) {
1140 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
1141 			   "reauth did not include encrypted data");
1142 		return -1;
1143 	}
1144 
1145 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1146 				       attr->encr_data_len, attr->iv, &eattr,
1147 				       0);
1148 	if (decrypted == NULL) {
1149 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1150 			   "data from notification message");
1151 		return -1;
1152 	}
1153 
1154 	if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
1155 		wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
1156 			   "message does not match with counter in reauth "
1157 			   "message");
1158 		os_free(decrypted);
1159 		return -1;
1160 	}
1161 
1162 	os_free(decrypted);
1163 	return 0;
1164 }
1165 
1166 
1167 static int eap_aka_process_notification_auth(struct eap_aka_data *data,
1168 					     const struct wpabuf *reqData,
1169 					     struct eap_sim_attrs *attr)
1170 {
1171 	if (attr->mac == NULL) {
1172 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
1173 			   "Notification message");
1174 		return -1;
1175 	}
1176 
1177 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1178 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
1179 			   "used invalid AT_MAC");
1180 		return -1;
1181 	}
1182 
1183 	if (data->reauth &&
1184 	    eap_aka_process_notification_reauth(data, attr)) {
1185 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
1186 			   "message after reauth");
1187 		return -1;
1188 	}
1189 
1190 	return 0;
1191 }
1192 
1193 
1194 static struct wpabuf * eap_aka_process_notification(
1195 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1196 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1197 {
1198 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
1199 	if (data->num_notification > 0) {
1200 		wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
1201 			   "rounds (only one allowed)");
1202 		return eap_aka_client_error(data, id,
1203 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1204 	}
1205 	data->num_notification++;
1206 	if (attr->notification == -1) {
1207 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
1208 			   "Notification message");
1209 		return eap_aka_client_error(data, id,
1210 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1211 	}
1212 
1213 	if ((attr->notification & 0x4000) == 0 &&
1214 	    eap_aka_process_notification_auth(data, reqData, attr)) {
1215 		return eap_aka_client_error(data, id,
1216 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1217 	}
1218 
1219 	eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
1220 	if (attr->notification >= 0 && attr->notification < 32768) {
1221 		data->error_code = attr->notification;
1222 		eap_aka_state(data, FAILURE);
1223 	} else if (attr->notification == EAP_SIM_SUCCESS &&
1224 		   data->state == RESULT_SUCCESS)
1225 		eap_aka_state(data, SUCCESS);
1226 	return eap_aka_response_notification(data, id, attr->notification);
1227 }
1228 
1229 
1230 static struct wpabuf * eap_aka_process_reauthentication(
1231 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1232 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1233 {
1234 	struct eap_sim_attrs eattr;
1235 	u8 *decrypted;
1236 
1237 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
1238 
1239 	if (attr->checkcode &&
1240 	    eap_aka_verify_checkcode(data, attr->checkcode,
1241 				     attr->checkcode_len)) {
1242 #ifdef TEST_FUZZ
1243 		wpa_printf(MSG_INFO,
1244 			   "TEST: Ignore AT_CHECKCODE mismatch for fuzz testing");
1245 #else /* TEST_FUZZ */
1246 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
1247 			   "message");
1248 #endif /* TEST_FUZZ */
1249 		return eap_aka_client_error(data, id,
1250 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1251 	}
1252 
1253 	if (data->reauth_id == NULL) {
1254 		wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
1255 			   "reauthentication, but no reauth_id available");
1256 		return eap_aka_client_error(data, id,
1257 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1258 	}
1259 
1260 	data->reauth = 1;
1261 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1262 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1263 			   "did not have valid AT_MAC");
1264 		return eap_aka_client_error(data, id,
1265 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1266 	}
1267 
1268 	/* At this stage the received MAC has been verified. Use this MAC for
1269 	 * reauth Session-Id calculation if all other checks pass.
1270 	 * The peer does not use the local MAC but the received MAC in deriving
1271 	 * Session-Id. */
1272 	os_memcpy(data->reauth_mac, attr->mac, EAP_SIM_MAC_LEN);
1273 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: Server MAC",
1274 		    data->reauth_mac, EAP_SIM_MAC_LEN);
1275 
1276 	if (attr->encr_data == NULL || attr->iv == NULL) {
1277 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1278 			   "message did not include encrypted data");
1279 		return eap_aka_client_error(data, id,
1280 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1281 	}
1282 
1283 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1284 				       attr->encr_data_len, attr->iv, &eattr,
1285 				       0);
1286 	if (decrypted == NULL) {
1287 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1288 			   "data from reauthentication message");
1289 		return eap_aka_client_error(data, id,
1290 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1291 	}
1292 
1293 	if (eattr.nonce_s == NULL || eattr.counter < 0) {
1294 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
1295 			   !eattr.nonce_s ? " AT_NONCE_S" : "",
1296 			   eattr.counter < 0 ? " AT_COUNTER" : "");
1297 		os_free(decrypted);
1298 		return eap_aka_client_error(data, id,
1299 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1300 	}
1301 
1302 	if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1303 		struct wpabuf *res;
1304 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
1305 			   "(%d <= %d)", eattr.counter, data->counter);
1306 		data->counter_too_small = eattr.counter;
1307 
1308 		/* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1309 		 * reauth_id must not be used to start a new reauthentication.
1310 		 * However, since it was used in the last EAP-Response-Identity
1311 		 * packet, it has to saved for the following fullauth to be
1312 		 * used in MK derivation. */
1313 		os_free(data->last_eap_identity);
1314 		data->last_eap_identity = data->reauth_id;
1315 		data->last_eap_identity_len = data->reauth_id_len;
1316 		data->reauth_id = NULL;
1317 		data->reauth_id_len = 0;
1318 
1319 		res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
1320 		os_free(decrypted);
1321 
1322 		return res;
1323 	}
1324 	data->counter = eattr.counter;
1325 
1326 	os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1327 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
1328 		    data->nonce_s, EAP_SIM_NONCE_S_LEN);
1329 
1330 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1331 		eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
1332 						 data->reauth_id,
1333 						 data->reauth_id_len,
1334 						 data->nonce_s,
1335 						 data->msk, data->emsk);
1336 	} else {
1337 		eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
1338 					   data->reauth_id_len,
1339 					   data->nonce_s, data->mk,
1340 					   data->msk, data->emsk);
1341 	}
1342 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1343 	eap_aka_learn_ids(sm, data, &eattr);
1344 
1345 	if (data->result_ind && attr->result_ind)
1346 		data->use_result_ind = 1;
1347 
1348 	if (data->state != FAILURE) {
1349 		eap_aka_state(data, data->use_result_ind ?
1350 			      RESULT_SUCCESS : SUCCESS);
1351 	}
1352 
1353 	data->num_id_req = 0;
1354 	data->num_notification = 0;
1355 	if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
1356 		wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
1357 			   "fast reauths performed - force fullauth");
1358 		eap_aka_clear_identities(sm, data,
1359 					 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1360 	}
1361 	os_free(decrypted);
1362 	return eap_aka_response_reauth(data, id, 0, data->nonce_s);
1363 }
1364 
1365 
1366 static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
1367 				       struct eap_method_ret *ret,
1368 				       const struct wpabuf *reqData)
1369 {
1370 	struct eap_aka_data *data = priv;
1371 	const struct eap_hdr *req;
1372 	u8 subtype, id;
1373 	struct wpabuf *res;
1374 	const u8 *pos;
1375 	struct eap_sim_attrs attr;
1376 	size_t len;
1377 
1378 	wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
1379 	if (eap_get_config_identity(sm, &len) == NULL) {
1380 		wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
1381 		eap_sm_request_identity(sm);
1382 		ret->ignore = true;
1383 		return NULL;
1384 	}
1385 
1386 	pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
1387 			       &len);
1388 	if (pos == NULL || len < 3) {
1389 		ret->ignore = true;
1390 		return NULL;
1391 	}
1392 	req = wpabuf_head(reqData);
1393 	id = req->identifier;
1394 	len = be_to_host16(req->length);
1395 
1396 	ret->ignore = false;
1397 	ret->methodState = METHOD_MAY_CONT;
1398 	ret->decision = DECISION_FAIL;
1399 	ret->allowNotifications = true;
1400 
1401 	subtype = *pos++;
1402 	wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
1403 	pos += 2; /* Reserved */
1404 
1405 	if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
1406 			       data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1407 			       0)) {
1408 		res = eap_aka_client_error(data, id,
1409 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1410 		goto done;
1411 	}
1412 
1413 	switch (subtype) {
1414 	case EAP_AKA_SUBTYPE_IDENTITY:
1415 		res = eap_aka_process_identity(sm, data, id, reqData, &attr);
1416 		break;
1417 	case EAP_AKA_SUBTYPE_CHALLENGE:
1418 		res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
1419 		break;
1420 	case EAP_AKA_SUBTYPE_NOTIFICATION:
1421 		res = eap_aka_process_notification(sm, data, id, reqData,
1422 						   &attr);
1423 		break;
1424 	case EAP_AKA_SUBTYPE_REAUTHENTICATION:
1425 		res = eap_aka_process_reauthentication(sm, data, id, reqData,
1426 						       &attr);
1427 		break;
1428 	case EAP_AKA_SUBTYPE_CLIENT_ERROR:
1429 		wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
1430 		res = eap_aka_client_error(data, id,
1431 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1432 		break;
1433 	default:
1434 		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
1435 		res = eap_aka_client_error(data, id,
1436 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1437 		break;
1438 	}
1439 
1440 done:
1441 	if (data->state == FAILURE) {
1442 		ret->decision = DECISION_FAIL;
1443 		ret->methodState = METHOD_DONE;
1444 	} else if (data->state == SUCCESS) {
1445 		ret->decision = data->use_result_ind ?
1446 			DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1447 		/*
1448 		 * It is possible for the server to reply with AKA
1449 		 * Notification, so we must allow the method to continue and
1450 		 * not only accept EAP-Success at this point.
1451 		 */
1452 		ret->methodState = data->use_result_ind ?
1453 			METHOD_DONE : METHOD_MAY_CONT;
1454 	} else if (data->state == RESULT_SUCCESS)
1455 		ret->methodState = METHOD_CONT;
1456 
1457 	if (ret->methodState == METHOD_DONE) {
1458 		ret->allowNotifications = false;
1459 	}
1460 
1461 	return res;
1462 }
1463 
1464 
1465 static bool eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
1466 {
1467 	struct eap_aka_data *data = priv;
1468 	return data->pseudonym || data->reauth_id;
1469 }
1470 
1471 
1472 static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
1473 {
1474 	struct eap_aka_data *data = priv;
1475 	eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
1476 	data->prev_id = -1;
1477 	wpabuf_free(data->id_msgs);
1478 	data->id_msgs = NULL;
1479 	data->use_result_ind = 0;
1480 	data->kdf_negotiation = 0;
1481 	eap_aka_clear_keys(data, 1);
1482 }
1483 
1484 
1485 static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
1486 {
1487 	struct eap_aka_data *data = priv;
1488 	data->num_id_req = 0;
1489 	data->num_notification = 0;
1490 	eap_aka_state(data, CONTINUE);
1491 	return priv;
1492 }
1493 
1494 
1495 static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
1496 				       size_t *len)
1497 {
1498 	struct eap_aka_data *data = priv;
1499 
1500 	if (data->reauth_id) {
1501 		*len = data->reauth_id_len;
1502 		return data->reauth_id;
1503 	}
1504 
1505 	if (data->pseudonym) {
1506 		*len = data->pseudonym_len;
1507 		return data->pseudonym;
1508 	}
1509 
1510 	return NULL;
1511 }
1512 
1513 
1514 static bool eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
1515 {
1516 	struct eap_aka_data *data = priv;
1517 	return data->state == SUCCESS;
1518 }
1519 
1520 
1521 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1522 {
1523 	struct eap_aka_data *data = priv;
1524 	u8 *key;
1525 
1526 	if (data->state != SUCCESS)
1527 		return NULL;
1528 
1529 	key = os_memdup(data->msk, EAP_SIM_KEYING_DATA_LEN);
1530 	if (key == NULL)
1531 		return NULL;
1532 
1533 	*len = EAP_SIM_KEYING_DATA_LEN;
1534 
1535 	return key;
1536 }
1537 
1538 
1539 static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1540 {
1541 	struct eap_aka_data *data = priv;
1542 	u8 *id;
1543 
1544 	if (data->state != SUCCESS)
1545 		return NULL;
1546 
1547 	if (!data->reauth)
1548 		*len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1549 	else
1550 		*len = 1 + EAP_SIM_NONCE_S_LEN + EAP_SIM_MAC_LEN;
1551 	id = os_malloc(*len);
1552 	if (id == NULL)
1553 		return NULL;
1554 
1555 	id[0] = data->eap_method;
1556 	if (!data->reauth) {
1557 		os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1558 		os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn,
1559 			  EAP_AKA_AUTN_LEN);
1560 	} else {
1561 		os_memcpy(id + 1, data->nonce_s, EAP_SIM_NONCE_S_LEN);
1562 		os_memcpy(id + 1 + EAP_SIM_NONCE_S_LEN, data->reauth_mac,
1563 			  EAP_SIM_MAC_LEN);
1564 	}
1565 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1566 
1567 	return id;
1568 }
1569 
1570 
1571 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1572 {
1573 	struct eap_aka_data *data = priv;
1574 	u8 *key;
1575 
1576 	if (data->state != SUCCESS)
1577 		return NULL;
1578 
1579 	key = os_memdup(data->emsk, EAP_EMSK_LEN);
1580 	if (key == NULL)
1581 		return NULL;
1582 
1583 	*len = EAP_EMSK_LEN;
1584 
1585 	return key;
1586 }
1587 
1588 
1589 static int eap_aka_get_error_code(void *priv)
1590 {
1591 	struct eap_aka_data *data = priv;
1592 	int current_data_error;
1593 
1594 	if (!data)
1595 		return NO_EAP_METHOD_ERROR;
1596 
1597 	current_data_error = data->error_code;
1598 
1599 	/* Now reset for next transaction */
1600 	data->error_code = NO_EAP_METHOD_ERROR;
1601 
1602 	return current_data_error;
1603 }
1604 
1605 
1606 int eap_peer_aka_register(void)
1607 {
1608 	struct eap_method *eap;
1609 
1610 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1611 				    EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1612 	if (eap == NULL)
1613 		return -1;
1614 
1615 	eap->init = eap_aka_init;
1616 	eap->deinit = eap_aka_deinit;
1617 	eap->process = eap_aka_process;
1618 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1619 	eap->getKey = eap_aka_getKey;
1620 	eap->getSessionId = eap_aka_get_session_id;
1621 	eap->has_reauth_data = eap_aka_has_reauth_data;
1622 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1623 	eap->init_for_reauth = eap_aka_init_for_reauth;
1624 	eap->get_identity = eap_aka_get_identity;
1625 	eap->get_emsk = eap_aka_get_emsk;
1626 	eap->get_error_code = eap_aka_get_error_code;
1627 
1628 	return eap_peer_method_register(eap);
1629 }
1630 
1631 
1632 #ifdef EAP_AKA_PRIME
1633 int eap_peer_aka_prime_register(void)
1634 {
1635 	struct eap_method *eap;
1636 
1637 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1638 				    EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1639 				    "AKA'");
1640 	if (eap == NULL)
1641 		return -1;
1642 
1643 	eap->init = eap_aka_prime_init;
1644 	eap->deinit = eap_aka_deinit;
1645 	eap->process = eap_aka_process;
1646 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1647 	eap->getKey = eap_aka_getKey;
1648 	eap->getSessionId = eap_aka_get_session_id;
1649 	eap->has_reauth_data = eap_aka_has_reauth_data;
1650 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1651 	eap->init_for_reauth = eap_aka_init_for_reauth;
1652 	eap->get_identity = eap_aka_get_identity;
1653 	eap->get_emsk = eap_aka_get_emsk;
1654 	eap->get_error_code = eap_aka_get_error_code;
1655 
1656 	return eap_peer_method_register(eap);
1657 }
1658 #endif /* EAP_AKA_PRIME */
1659