xref: /freebsd/contrib/wpa/src/eap_peer/eap_aka.c (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
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 *msg)
446 {
447 	if (msg == NULL)
448 		return -1;
449 
450 	if (data->id_msgs == NULL) {
451 		data->id_msgs = wpabuf_dup(msg);
452 		return data->id_msgs == NULL ? -1 : 0;
453 	}
454 
455 	if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
456 		return -1;
457 	wpabuf_put_buf(data->id_msgs, msg);
458 
459 	return 0;
460 }
461 
462 
463 static void eap_aka_add_checkcode(struct eap_aka_data *data,
464 				  struct eap_sim_msg *msg)
465 {
466 	const u8 *addr;
467 	size_t len;
468 	u8 hash[SHA256_MAC_LEN];
469 
470 	wpa_printf(MSG_DEBUG, "   AT_CHECKCODE");
471 
472 	if (data->id_msgs == NULL) {
473 		/*
474 		 * No EAP-AKA/Identity packets were exchanged - send empty
475 		 * checkcode.
476 		 */
477 		eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
478 		return;
479 	}
480 
481 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
482 	addr = wpabuf_head(data->id_msgs);
483 	len = wpabuf_len(data->id_msgs);
484 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
485 #ifdef EAP_AKA_PRIME
486 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
487 		sha256_vector(1, &addr, &len, hash);
488 	else
489 #endif /* EAP_AKA_PRIME */
490 		sha1_vector(1, &addr, &len, hash);
491 
492 	eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
493 			data->eap_method == EAP_TYPE_AKA_PRIME ?
494 			EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
495 }
496 
497 
498 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
499 				    const u8 *checkcode, size_t checkcode_len)
500 {
501 	const u8 *addr;
502 	size_t len;
503 	u8 hash[SHA256_MAC_LEN];
504 	size_t hash_len;
505 
506 	if (checkcode == NULL)
507 		return -1;
508 
509 	if (data->id_msgs == NULL) {
510 		if (checkcode_len != 0) {
511 			wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
512 				   "indicates that AKA/Identity messages were "
513 				   "used, but they were not");
514 			return -1;
515 		}
516 		return 0;
517 	}
518 
519 	hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
520 		EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
521 
522 	if (checkcode_len != hash_len) {
523 		wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
524 			   "indicates that AKA/Identity message were not "
525 			   "used, but they were");
526 		return -1;
527 	}
528 
529 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
530 	addr = wpabuf_head(data->id_msgs);
531 	len = wpabuf_len(data->id_msgs);
532 #ifdef EAP_AKA_PRIME
533 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
534 		sha256_vector(1, &addr, &len, hash);
535 	else
536 #endif /* EAP_AKA_PRIME */
537 		sha1_vector(1, &addr, &len, hash);
538 
539 	if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
540 		wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
541 		return -1;
542 	}
543 
544 	return 0;
545 }
546 
547 
548 static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
549 					    int err)
550 {
551 	struct eap_sim_msg *msg;
552 
553 	eap_aka_state(data, FAILURE);
554 	data->num_id_req = 0;
555 	data->num_notification = 0;
556 
557 	wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
558 		   err);
559 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
560 			       EAP_AKA_SUBTYPE_CLIENT_ERROR);
561 	eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
562 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
563 }
564 
565 
566 static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
567 						     u8 id)
568 {
569 	struct eap_sim_msg *msg;
570 
571 	eap_aka_state(data, FAILURE);
572 	data->num_id_req = 0;
573 	data->num_notification = 0;
574 
575 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
576 		   "(id=%d)", id);
577 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
578 			       EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
579 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
580 }
581 
582 
583 static struct wpabuf * eap_aka_synchronization_failure(
584 	struct eap_aka_data *data, u8 id, struct eap_sim_attrs *attr)
585 {
586 	struct eap_sim_msg *msg;
587 
588 	data->num_id_req = 0;
589 	data->num_notification = 0;
590 
591 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
592 		   "(id=%d)", id);
593 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
594 			       EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
595 	wpa_printf(MSG_DEBUG, "   AT_AUTS");
596 	eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
597 			     EAP_AKA_AUTS_LEN);
598 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
599 		size_t i;
600 
601 		for (i = 0; i < attr->kdf_count; i++) {
602 			wpa_printf(MSG_DEBUG, "   AT_KDF");
603 			eap_sim_msg_add(msg, EAP_SIM_AT_KDF, attr->kdf[i],
604 					NULL, 0);
605 		}
606 	}
607 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
608 }
609 
610 
611 static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
612 						 struct eap_aka_data *data,
613 						 u8 id,
614 						 enum eap_sim_id_req id_req)
615 {
616 	const u8 *identity = NULL;
617 	size_t identity_len = 0;
618 	struct eap_sim_msg *msg;
619 
620 	data->reauth = 0;
621 	if (id_req == ANY_ID && data->reauth_id) {
622 		identity = data->reauth_id;
623 		identity_len = data->reauth_id_len;
624 		data->reauth = 1;
625 	} else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
626 		   data->pseudonym &&
627 		   !eap_sim_anonymous_username(data->pseudonym,
628 					       data->pseudonym_len)) {
629 		identity = data->pseudonym;
630 		identity_len = data->pseudonym_len;
631 		eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
632 	} else if (id_req != NO_ID_REQ) {
633 		identity = eap_get_config_identity(sm, &identity_len);
634 		if (identity) {
635 			int ids = CLEAR_PSEUDONYM | CLEAR_REAUTH_ID;
636 
637 			if (data->pseudonym &&
638 			    eap_sim_anonymous_username(data->pseudonym,
639 						       data->pseudonym_len))
640 				ids &= ~CLEAR_PSEUDONYM;
641 			eap_aka_clear_identities(sm, data, ids);
642 		}
643 	}
644 	if (id_req != NO_ID_REQ)
645 		eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
646 
647 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
648 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
649 			       EAP_AKA_SUBTYPE_IDENTITY);
650 
651 	if (identity) {
652 		wpa_hexdump_ascii(MSG_DEBUG, "   AT_IDENTITY",
653 				  identity, identity_len);
654 		eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
655 				identity, identity_len);
656 	}
657 
658 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
659 }
660 
661 
662 static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
663 						  u8 id)
664 {
665 	struct eap_sim_msg *msg;
666 
667 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
668 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
669 			       EAP_AKA_SUBTYPE_CHALLENGE);
670 	wpa_printf(MSG_DEBUG, "   AT_RES");
671 	eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
672 			data->res, data->res_len);
673 	eap_aka_add_checkcode(data, msg);
674 	if (data->use_result_ind) {
675 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
676 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
677 	}
678 	wpa_printf(MSG_DEBUG, "   AT_MAC");
679 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
680 	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, (u8 *) "",
681 				  0);
682 }
683 
684 
685 static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
686 					       u8 id, int counter_too_small,
687 					       const u8 *nonce_s)
688 {
689 	struct eap_sim_msg *msg;
690 	unsigned int counter;
691 
692 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
693 		   id);
694 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
695 			       EAP_AKA_SUBTYPE_REAUTHENTICATION);
696 	wpa_printf(MSG_DEBUG, "   AT_IV");
697 	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
698 	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
699 
700 	if (counter_too_small) {
701 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER_TOO_SMALL");
702 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
703 		counter = data->counter_too_small;
704 	} else
705 		counter = data->counter;
706 
707 	wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", counter);
708 	eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
709 
710 	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
711 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
712 			   "AT_ENCR_DATA");
713 		eap_sim_msg_free(msg);
714 		return NULL;
715 	}
716 	eap_aka_add_checkcode(data, msg);
717 	if (data->use_result_ind) {
718 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
719 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
720 	}
721 	wpa_printf(MSG_DEBUG, "   AT_MAC");
722 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
723 	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, nonce_s,
724 				  EAP_SIM_NONCE_S_LEN);
725 }
726 
727 
728 static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
729 						     u8 id, u16 notification)
730 {
731 	struct eap_sim_msg *msg;
732 	u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
733 
734 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
735 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
736 			       EAP_AKA_SUBTYPE_NOTIFICATION);
737 	if (k_aut && data->reauth) {
738 		wpa_printf(MSG_DEBUG, "   AT_IV");
739 		wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
740 		eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
741 					   EAP_SIM_AT_ENCR_DATA);
742 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", data->counter);
743 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
744 				NULL, 0);
745 		if (eap_sim_msg_add_encr_end(msg, data->k_encr,
746 					     EAP_SIM_AT_PADDING)) {
747 			wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
748 				   "AT_ENCR_DATA");
749 			eap_sim_msg_free(msg);
750 			return NULL;
751 		}
752 	}
753 	if (k_aut) {
754 		wpa_printf(MSG_DEBUG, "   AT_MAC");
755 		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
756 	}
757 	return eap_sim_msg_finish(msg, data->eap_method, k_aut, (u8 *) "", 0);
758 }
759 
760 
761 static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
762 						struct eap_aka_data *data,
763 						u8 id,
764 						const struct wpabuf *reqData,
765 						struct eap_sim_attrs *attr)
766 {
767 	int id_error;
768 	struct wpabuf *buf;
769 
770 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
771 
772 	id_error = 0;
773 	switch (attr->id_req) {
774 	case NO_ID_REQ:
775 		break;
776 	case ANY_ID:
777 		if (data->num_id_req > 0)
778 			id_error++;
779 		data->num_id_req++;
780 		break;
781 	case FULLAUTH_ID:
782 		if (data->num_id_req > 1)
783 			id_error++;
784 		data->num_id_req++;
785 		break;
786 	case PERMANENT_ID:
787 		if (data->num_id_req > 2)
788 			id_error++;
789 		data->num_id_req++;
790 		break;
791 	}
792 	if (id_error) {
793 		wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
794 			   "used within one authentication");
795 		return eap_aka_client_error(data, id,
796 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
797 	}
798 
799 	buf = eap_aka_response_identity(sm, data, id, attr->id_req);
800 
801 	if (data->prev_id != id) {
802 		eap_aka_add_id_msg(data, reqData);
803 		eap_aka_add_id_msg(data, buf);
804 		data->prev_id = id;
805 	}
806 
807 	return buf;
808 }
809 
810 
811 static int eap_aka_verify_mac(struct eap_aka_data *data,
812 			      const struct wpabuf *req,
813 			      const u8 *mac, const u8 *extra,
814 			      size_t extra_len)
815 {
816 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
817 		return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
818 						 extra_len);
819 	return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
820 }
821 
822 
823 #ifdef EAP_AKA_PRIME
824 static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
825 						u8 id, u16 kdf)
826 {
827 	struct eap_sim_msg *msg;
828 
829 	data->kdf_negotiation = 1;
830 	data->kdf = kdf;
831 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
832 		   "select)", id);
833 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
834 			       EAP_AKA_SUBTYPE_CHALLENGE);
835 	wpa_printf(MSG_DEBUG, "   AT_KDF");
836 	eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
837 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
838 }
839 
840 
841 static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
842 					     u8 id, struct eap_sim_attrs *attr)
843 {
844 	size_t i;
845 
846 	for (i = 0; i < attr->kdf_count; i++) {
847 		if (attr->kdf[i] == EAP_AKA_PRIME_KDF) {
848 			os_memcpy(data->last_kdf_attrs, attr->kdf,
849 				  sizeof(u16) * attr->kdf_count);
850 			data->last_kdf_count = attr->kdf_count;
851 			return eap_aka_prime_kdf_select(data, id,
852 							EAP_AKA_PRIME_KDF);
853 		}
854 	}
855 
856 	/* No matching KDF found - fail authentication as if AUTN had been
857 	 * incorrect */
858 	return eap_aka_authentication_reject(data, id);
859 }
860 
861 
862 static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
863 				   struct eap_sim_attrs *attr)
864 {
865 	size_t i, j;
866 
867 	if (attr->kdf_count == 0)
868 		return 0;
869 
870 	/* The only allowed (and required) duplication of a KDF is the addition
871 	 * of the selected KDF into the beginning of the list. */
872 
873 	if (data->kdf_negotiation) {
874 		/* When the peer receives the new EAP-Request/AKA'-Challenge
875 		 * message, must check only requested change occurred in the
876 		 * list of AT_KDF attributes. If there are any other changes,
877 		 * the peer must behave like the case that AT_MAC had been
878 		 * incorrect and authentication is failed. These are defined in
879 		 * EAP-AKA' specification RFC 5448, Section 3.2. */
880 		if (attr->kdf[0] != data->kdf) {
881 			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
882 				   "accept the selected KDF");
883 			return -1;
884 		}
885 
886 		if (attr->kdf_count > EAP_AKA_PRIME_KDF_MAX ||
887 		    attr->kdf_count != data->last_kdf_count + 1) {
888 			wpa_printf(MSG_WARNING,
889 				   "EAP-AKA': The length of KDF attributes is wrong");
890 			return -1;
891 		}
892 
893 		for (i = 1; i < attr->kdf_count; i++) {
894 			if (attr->kdf[i] != data->last_kdf_attrs[i - 1]) {
895 				wpa_printf(MSG_WARNING,
896 					   "EAP-AKA': The KDF attributes except selected KDF are not same as original one");
897 				return -1;
898 			}
899 		}
900 	}
901 
902 	for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
903 		for (j = i + 1; j < attr->kdf_count; j++) {
904 			if (attr->kdf[i] == attr->kdf[j]) {
905 				wpa_printf(MSG_WARNING, "EAP-AKA': The server "
906 					   "included a duplicated KDF");
907 				return 0;
908 			}
909 		}
910 	}
911 
912 	return 1;
913 }
914 #endif /* EAP_AKA_PRIME */
915 
916 
917 static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
918 						 struct eap_aka_data *data,
919 						 u8 id,
920 						 const struct wpabuf *reqData,
921 						 struct eap_sim_attrs *attr)
922 {
923 	const u8 *identity;
924 	size_t identity_len;
925 	int res;
926 	struct eap_sim_attrs eattr;
927 
928 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
929 
930 	if (attr->checkcode &&
931 	    eap_aka_verify_checkcode(data, attr->checkcode,
932 				     attr->checkcode_len)) {
933 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
934 			   "message");
935 #ifdef TEST_FUZZ
936 		wpa_printf(MSG_INFO,
937 			   "TEST: Ignore AT_CHECKCODE mismatch for fuzz testing");
938 #else /* TEST_FUZZ */
939 		return eap_aka_client_error(data, id,
940 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
941 #endif /* TEST_FUZZ */
942 	}
943 
944 #ifdef EAP_AKA_PRIME
945 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
946 		if (!attr->kdf_input || attr->kdf_input_len == 0) {
947 			wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
948 				   "did not include non-empty AT_KDF_INPUT");
949 			/* Fail authentication as if AUTN had been incorrect */
950 			return eap_aka_authentication_reject(data, id);
951 		}
952 		os_free(data->network_name);
953 		data->network_name = os_memdup(attr->kdf_input,
954 					       attr->kdf_input_len);
955 		if (data->network_name == NULL) {
956 			wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
957 				   "storing Network Name");
958 			return eap_aka_authentication_reject(data, id);
959 		}
960 		data->network_name_len = attr->kdf_input_len;
961 		wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
962 				  "(AT_KDF_INPUT)",
963 				  data->network_name, data->network_name_len);
964 		/* TODO: check Network Name per 3GPP.33.402 */
965 
966 		res = eap_aka_prime_kdf_valid(data, attr);
967 		if (res == 0)
968 			return eap_aka_authentication_reject(data, id);
969 		else if (res == -1)
970 			return eap_aka_client_error(
971 				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
972 
973 		if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
974 			return eap_aka_prime_kdf_neg(data, id, attr);
975 
976 		data->kdf = EAP_AKA_PRIME_KDF;
977 		wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
978 	}
979 
980 	if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
981 		u16 flags = WPA_GET_BE16(attr->bidding);
982 		if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
983 		    eap_allowed_method(sm, EAP_VENDOR_IETF,
984 				       EAP_TYPE_AKA_PRIME)) {
985 			wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
986 				   "AKA' to AKA detected");
987 			/* Fail authentication as if AUTN had been incorrect */
988 			return eap_aka_authentication_reject(data, id);
989 		}
990 	}
991 #endif /* EAP_AKA_PRIME */
992 
993 	data->reauth = 0;
994 	if (!attr->mac || !attr->rand || !attr->autn) {
995 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
996 			   "did not include%s%s%s",
997 			   !attr->mac ? " AT_MAC" : "",
998 			   !attr->rand ? " AT_RAND" : "",
999 			   !attr->autn ? " AT_AUTN" : "");
1000 		return eap_aka_client_error(data, id,
1001 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1002 	}
1003 	os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
1004 	os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
1005 
1006 	res = eap_aka_umts_auth(sm, data);
1007 	if (res == -1) {
1008 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
1009 			   "failed (AUTN)");
1010 		return eap_aka_authentication_reject(data, id);
1011 	} else if (res == -2) {
1012 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
1013 			   "failed (AUTN seq# -> AUTS)");
1014 		return eap_aka_synchronization_failure(data, id, attr);
1015 	} else if (res > 0) {
1016 		wpa_printf(MSG_DEBUG, "EAP-AKA: Wait for external USIM processing");
1017 		return NULL;
1018 	} else if (res) {
1019 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
1020 		return eap_aka_client_error(data, id,
1021 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1022 	}
1023 #ifdef EAP_AKA_PRIME
1024 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1025 		/* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
1026 		 * needed 6-octet SQN ^ AK for CK',IK' derivation */
1027 		u16 amf = WPA_GET_BE16(data->autn + 6);
1028 		if (!(amf & 0x8000)) {
1029 			wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
1030 				   "not set (AMF=0x%4x)", amf);
1031 			return eap_aka_authentication_reject(data, id);
1032 		}
1033 		eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
1034 						 data->autn,
1035 						 data->network_name,
1036 						 data->network_name_len);
1037 	}
1038 #endif /* EAP_AKA_PRIME */
1039 	if (data->last_eap_identity) {
1040 		identity = data->last_eap_identity;
1041 		identity_len = data->last_eap_identity_len;
1042 	} else if (data->pseudonym &&
1043 		   !eap_sim_anonymous_username(data->pseudonym,
1044 					       data->pseudonym_len)) {
1045 		identity = data->pseudonym;
1046 		identity_len = data->pseudonym_len;
1047 	} else {
1048 		struct eap_peer_config *config;
1049 
1050 		config = eap_get_config(sm);
1051 		if (config && config->imsi_identity) {
1052 			identity = config->imsi_identity;
1053 			identity_len = config->imsi_identity_len;
1054 		} else {
1055 			identity = eap_get_config_identity(sm, &identity_len);
1056 		}
1057 	}
1058 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
1059 			  "derivation", identity, identity_len);
1060 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1061 		eap_aka_prime_derive_keys(identity, identity_len, data->ik,
1062 					  data->ck, data->k_encr, data->k_aut,
1063 					  data->k_re, data->msk, data->emsk);
1064 	} else {
1065 		eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
1066 				  data->mk);
1067 		eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
1068 				    data->msk, data->emsk);
1069 	}
1070 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1071 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
1072 			   "used invalid AT_MAC");
1073 #ifdef TEST_FUZZ
1074 		wpa_printf(MSG_INFO,
1075 			   "TEST: Ignore AT_MAC mismatch for fuzz testing");
1076 #else /* TEST_FUZZ */
1077 		return eap_aka_client_error(data, id,
1078 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1079 #endif /* TEST_FUZZ */
1080 	}
1081 
1082 	/* Old reauthentication identity must not be used anymore. In
1083 	 * other words, if no new identities are received, full
1084 	 * authentication will be used on next reauthentication (using
1085 	 * pseudonym identity or permanent identity). */
1086 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1087 
1088 	if (attr->encr_data) {
1089 		u8 *decrypted;
1090 		decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1091 					       attr->encr_data_len, attr->iv,
1092 					       &eattr, 0);
1093 		if (decrypted == NULL) {
1094 			return eap_aka_client_error(
1095 				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1096 		}
1097 		eap_aka_learn_ids(sm, data, &eattr);
1098 		os_free(decrypted);
1099 	}
1100 
1101 	if (data->result_ind && attr->result_ind)
1102 		data->use_result_ind = 1;
1103 
1104 	if (data->state != FAILURE) {
1105 		eap_aka_state(data, data->use_result_ind ?
1106 			      RESULT_SUCCESS : SUCCESS);
1107 	}
1108 
1109 	data->num_id_req = 0;
1110 	data->num_notification = 0;
1111 	/* RFC 4187 specifies that counter is initialized to one after
1112 	 * fullauth, but initializing it to zero makes it easier to implement
1113 	 * reauth verification. */
1114 	data->counter = 0;
1115 	return eap_aka_response_challenge(data, id);
1116 }
1117 
1118 
1119 static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
1120 					       struct eap_sim_attrs *attr)
1121 {
1122 	struct eap_sim_attrs eattr;
1123 	u8 *decrypted;
1124 
1125 	if (attr->encr_data == NULL || attr->iv == NULL) {
1126 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
1127 			   "reauth did not include encrypted data");
1128 		return -1;
1129 	}
1130 
1131 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1132 				       attr->encr_data_len, attr->iv, &eattr,
1133 				       0);
1134 	if (decrypted == NULL) {
1135 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1136 			   "data from notification message");
1137 		return -1;
1138 	}
1139 
1140 	if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
1141 		wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
1142 			   "message does not match with counter in reauth "
1143 			   "message");
1144 		os_free(decrypted);
1145 		return -1;
1146 	}
1147 
1148 	os_free(decrypted);
1149 	return 0;
1150 }
1151 
1152 
1153 static int eap_aka_process_notification_auth(struct eap_aka_data *data,
1154 					     const struct wpabuf *reqData,
1155 					     struct eap_sim_attrs *attr)
1156 {
1157 	if (attr->mac == NULL) {
1158 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
1159 			   "Notification message");
1160 		return -1;
1161 	}
1162 
1163 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1164 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
1165 			   "used invalid AT_MAC");
1166 		return -1;
1167 	}
1168 
1169 	if (data->reauth &&
1170 	    eap_aka_process_notification_reauth(data, attr)) {
1171 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
1172 			   "message after reauth");
1173 		return -1;
1174 	}
1175 
1176 	return 0;
1177 }
1178 
1179 
1180 static struct wpabuf * eap_aka_process_notification(
1181 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1182 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1183 {
1184 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
1185 	if (data->num_notification > 0) {
1186 		wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
1187 			   "rounds (only one allowed)");
1188 		return eap_aka_client_error(data, id,
1189 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1190 	}
1191 	data->num_notification++;
1192 	if (attr->notification == -1) {
1193 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
1194 			   "Notification message");
1195 		return eap_aka_client_error(data, id,
1196 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1197 	}
1198 
1199 	if ((attr->notification & 0x4000) == 0 &&
1200 	    eap_aka_process_notification_auth(data, reqData, attr)) {
1201 		return eap_aka_client_error(data, id,
1202 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1203 	}
1204 
1205 	eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
1206 	if (attr->notification >= 0 && attr->notification < 32768) {
1207 		data->error_code = attr->notification;
1208 		eap_aka_state(data, FAILURE);
1209 	} else if (attr->notification == EAP_SIM_SUCCESS &&
1210 		   data->state == RESULT_SUCCESS)
1211 		eap_aka_state(data, SUCCESS);
1212 	return eap_aka_response_notification(data, id, attr->notification);
1213 }
1214 
1215 
1216 static struct wpabuf * eap_aka_process_reauthentication(
1217 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1218 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1219 {
1220 	struct eap_sim_attrs eattr;
1221 	u8 *decrypted;
1222 
1223 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
1224 
1225 	if (attr->checkcode &&
1226 	    eap_aka_verify_checkcode(data, attr->checkcode,
1227 				     attr->checkcode_len)) {
1228 #ifdef TEST_FUZZ
1229 		wpa_printf(MSG_INFO,
1230 			   "TEST: Ignore AT_CHECKCODE mismatch for fuzz testing");
1231 #else /* TEST_FUZZ */
1232 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
1233 			   "message");
1234 #endif /* TEST_FUZZ */
1235 		return eap_aka_client_error(data, id,
1236 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1237 	}
1238 
1239 	if (data->reauth_id == NULL) {
1240 		wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
1241 			   "reauthentication, but no reauth_id available");
1242 		return eap_aka_client_error(data, id,
1243 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1244 	}
1245 
1246 	data->reauth = 1;
1247 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1248 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1249 			   "did not have valid AT_MAC");
1250 		return eap_aka_client_error(data, id,
1251 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1252 	}
1253 
1254 	/* At this stage the received MAC has been verified. Use this MAC for
1255 	 * reauth Session-Id calculation if all other checks pass.
1256 	 * The peer does not use the local MAC but the received MAC in deriving
1257 	 * Session-Id. */
1258 	os_memcpy(data->reauth_mac, attr->mac, EAP_SIM_MAC_LEN);
1259 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: Server MAC",
1260 		    data->reauth_mac, EAP_SIM_MAC_LEN);
1261 
1262 	if (attr->encr_data == NULL || attr->iv == NULL) {
1263 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1264 			   "message did not include encrypted data");
1265 		return eap_aka_client_error(data, id,
1266 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1267 	}
1268 
1269 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1270 				       attr->encr_data_len, attr->iv, &eattr,
1271 				       0);
1272 	if (decrypted == NULL) {
1273 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1274 			   "data from reauthentication message");
1275 		return eap_aka_client_error(data, id,
1276 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1277 	}
1278 
1279 	if (eattr.nonce_s == NULL || eattr.counter < 0) {
1280 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
1281 			   !eattr.nonce_s ? " AT_NONCE_S" : "",
1282 			   eattr.counter < 0 ? " AT_COUNTER" : "");
1283 		os_free(decrypted);
1284 		return eap_aka_client_error(data, id,
1285 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1286 	}
1287 
1288 	if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1289 		struct wpabuf *res;
1290 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
1291 			   "(%d <= %d)", eattr.counter, data->counter);
1292 		data->counter_too_small = eattr.counter;
1293 
1294 		/* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1295 		 * reauth_id must not be used to start a new reauthentication.
1296 		 * However, since it was used in the last EAP-Response-Identity
1297 		 * packet, it has to saved for the following fullauth to be
1298 		 * used in MK derivation. */
1299 		os_free(data->last_eap_identity);
1300 		data->last_eap_identity = data->reauth_id;
1301 		data->last_eap_identity_len = data->reauth_id_len;
1302 		data->reauth_id = NULL;
1303 		data->reauth_id_len = 0;
1304 
1305 		res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
1306 		os_free(decrypted);
1307 
1308 		return res;
1309 	}
1310 	data->counter = eattr.counter;
1311 
1312 	os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1313 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
1314 		    data->nonce_s, EAP_SIM_NONCE_S_LEN);
1315 
1316 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1317 		eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
1318 						 data->reauth_id,
1319 						 data->reauth_id_len,
1320 						 data->nonce_s,
1321 						 data->msk, data->emsk);
1322 	} else {
1323 		eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
1324 					   data->reauth_id_len,
1325 					   data->nonce_s, data->mk,
1326 					   data->msk, data->emsk);
1327 	}
1328 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1329 	eap_aka_learn_ids(sm, data, &eattr);
1330 
1331 	if (data->result_ind && attr->result_ind)
1332 		data->use_result_ind = 1;
1333 
1334 	if (data->state != FAILURE) {
1335 		eap_aka_state(data, data->use_result_ind ?
1336 			      RESULT_SUCCESS : SUCCESS);
1337 	}
1338 
1339 	data->num_id_req = 0;
1340 	data->num_notification = 0;
1341 	if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
1342 		wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
1343 			   "fast reauths performed - force fullauth");
1344 		eap_aka_clear_identities(sm, data,
1345 					 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1346 	}
1347 	os_free(decrypted);
1348 	return eap_aka_response_reauth(data, id, 0, data->nonce_s);
1349 }
1350 
1351 
1352 static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
1353 				       struct eap_method_ret *ret,
1354 				       const struct wpabuf *reqData)
1355 {
1356 	struct eap_aka_data *data = priv;
1357 	const struct eap_hdr *req;
1358 	u8 subtype, id;
1359 	struct wpabuf *res;
1360 	const u8 *pos;
1361 	struct eap_sim_attrs attr;
1362 	size_t len;
1363 
1364 	wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
1365 	if (eap_get_config_identity(sm, &len) == NULL) {
1366 		wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
1367 		eap_sm_request_identity(sm);
1368 		ret->ignore = TRUE;
1369 		return NULL;
1370 	}
1371 
1372 	pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
1373 			       &len);
1374 	if (pos == NULL || len < 3) {
1375 		ret->ignore = TRUE;
1376 		return NULL;
1377 	}
1378 	req = wpabuf_head(reqData);
1379 	id = req->identifier;
1380 	len = be_to_host16(req->length);
1381 
1382 	ret->ignore = FALSE;
1383 	ret->methodState = METHOD_MAY_CONT;
1384 	ret->decision = DECISION_FAIL;
1385 	ret->allowNotifications = TRUE;
1386 
1387 	subtype = *pos++;
1388 	wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
1389 	pos += 2; /* Reserved */
1390 
1391 	if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
1392 			       data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1393 			       0)) {
1394 		res = eap_aka_client_error(data, id,
1395 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1396 		goto done;
1397 	}
1398 
1399 	switch (subtype) {
1400 	case EAP_AKA_SUBTYPE_IDENTITY:
1401 		res = eap_aka_process_identity(sm, data, id, reqData, &attr);
1402 		break;
1403 	case EAP_AKA_SUBTYPE_CHALLENGE:
1404 		res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
1405 		break;
1406 	case EAP_AKA_SUBTYPE_NOTIFICATION:
1407 		res = eap_aka_process_notification(sm, data, id, reqData,
1408 						   &attr);
1409 		break;
1410 	case EAP_AKA_SUBTYPE_REAUTHENTICATION:
1411 		res = eap_aka_process_reauthentication(sm, data, id, reqData,
1412 						       &attr);
1413 		break;
1414 	case EAP_AKA_SUBTYPE_CLIENT_ERROR:
1415 		wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
1416 		res = eap_aka_client_error(data, id,
1417 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1418 		break;
1419 	default:
1420 		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
1421 		res = eap_aka_client_error(data, id,
1422 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1423 		break;
1424 	}
1425 
1426 done:
1427 	if (data->state == FAILURE) {
1428 		ret->decision = DECISION_FAIL;
1429 		ret->methodState = METHOD_DONE;
1430 	} else if (data->state == SUCCESS) {
1431 		ret->decision = data->use_result_ind ?
1432 			DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1433 		/*
1434 		 * It is possible for the server to reply with AKA
1435 		 * Notification, so we must allow the method to continue and
1436 		 * not only accept EAP-Success at this point.
1437 		 */
1438 		ret->methodState = data->use_result_ind ?
1439 			METHOD_DONE : METHOD_MAY_CONT;
1440 	} else if (data->state == RESULT_SUCCESS)
1441 		ret->methodState = METHOD_CONT;
1442 
1443 	if (ret->methodState == METHOD_DONE) {
1444 		ret->allowNotifications = FALSE;
1445 	}
1446 
1447 	return res;
1448 }
1449 
1450 
1451 static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
1452 {
1453 	struct eap_aka_data *data = priv;
1454 	return data->pseudonym || data->reauth_id;
1455 }
1456 
1457 
1458 static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
1459 {
1460 	struct eap_aka_data *data = priv;
1461 	eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
1462 	data->prev_id = -1;
1463 	wpabuf_free(data->id_msgs);
1464 	data->id_msgs = NULL;
1465 	data->use_result_ind = 0;
1466 	data->kdf_negotiation = 0;
1467 	eap_aka_clear_keys(data, 1);
1468 }
1469 
1470 
1471 static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
1472 {
1473 	struct eap_aka_data *data = priv;
1474 	data->num_id_req = 0;
1475 	data->num_notification = 0;
1476 	eap_aka_state(data, CONTINUE);
1477 	return priv;
1478 }
1479 
1480 
1481 static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
1482 				       size_t *len)
1483 {
1484 	struct eap_aka_data *data = priv;
1485 
1486 	if (data->reauth_id) {
1487 		*len = data->reauth_id_len;
1488 		return data->reauth_id;
1489 	}
1490 
1491 	if (data->pseudonym) {
1492 		*len = data->pseudonym_len;
1493 		return data->pseudonym;
1494 	}
1495 
1496 	return NULL;
1497 }
1498 
1499 
1500 static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
1501 {
1502 	struct eap_aka_data *data = priv;
1503 	return data->state == SUCCESS;
1504 }
1505 
1506 
1507 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1508 {
1509 	struct eap_aka_data *data = priv;
1510 	u8 *key;
1511 
1512 	if (data->state != SUCCESS)
1513 		return NULL;
1514 
1515 	key = os_memdup(data->msk, EAP_SIM_KEYING_DATA_LEN);
1516 	if (key == NULL)
1517 		return NULL;
1518 
1519 	*len = EAP_SIM_KEYING_DATA_LEN;
1520 
1521 	return key;
1522 }
1523 
1524 
1525 static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1526 {
1527 	struct eap_aka_data *data = priv;
1528 	u8 *id;
1529 
1530 	if (data->state != SUCCESS)
1531 		return NULL;
1532 
1533 	if (!data->reauth)
1534 		*len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1535 	else
1536 		*len = 1 + EAP_SIM_NONCE_S_LEN + EAP_SIM_MAC_LEN;
1537 	id = os_malloc(*len);
1538 	if (id == NULL)
1539 		return NULL;
1540 
1541 	id[0] = data->eap_method;
1542 	if (!data->reauth) {
1543 		os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1544 		os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn,
1545 			  EAP_AKA_AUTN_LEN);
1546 	} else {
1547 		os_memcpy(id + 1, data->nonce_s, EAP_SIM_NONCE_S_LEN);
1548 		os_memcpy(id + 1 + EAP_SIM_NONCE_S_LEN, data->reauth_mac,
1549 			  EAP_SIM_MAC_LEN);
1550 	}
1551 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1552 
1553 	return id;
1554 }
1555 
1556 
1557 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1558 {
1559 	struct eap_aka_data *data = priv;
1560 	u8 *key;
1561 
1562 	if (data->state != SUCCESS)
1563 		return NULL;
1564 
1565 	key = os_memdup(data->emsk, EAP_EMSK_LEN);
1566 	if (key == NULL)
1567 		return NULL;
1568 
1569 	*len = EAP_EMSK_LEN;
1570 
1571 	return key;
1572 }
1573 
1574 
1575 static int eap_aka_get_error_code(void *priv)
1576 {
1577 	struct eap_aka_data *data = priv;
1578 	int current_data_error;
1579 
1580 	if (!data)
1581 		return NO_EAP_METHOD_ERROR;
1582 
1583 	current_data_error = data->error_code;
1584 
1585 	/* Now reset for next transaction */
1586 	data->error_code = NO_EAP_METHOD_ERROR;
1587 
1588 	return current_data_error;
1589 }
1590 
1591 
1592 int eap_peer_aka_register(void)
1593 {
1594 	struct eap_method *eap;
1595 
1596 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1597 				    EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1598 	if (eap == NULL)
1599 		return -1;
1600 
1601 	eap->init = eap_aka_init;
1602 	eap->deinit = eap_aka_deinit;
1603 	eap->process = eap_aka_process;
1604 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1605 	eap->getKey = eap_aka_getKey;
1606 	eap->getSessionId = eap_aka_get_session_id;
1607 	eap->has_reauth_data = eap_aka_has_reauth_data;
1608 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1609 	eap->init_for_reauth = eap_aka_init_for_reauth;
1610 	eap->get_identity = eap_aka_get_identity;
1611 	eap->get_emsk = eap_aka_get_emsk;
1612 	eap->get_error_code = eap_aka_get_error_code;
1613 
1614 	return eap_peer_method_register(eap);
1615 }
1616 
1617 
1618 #ifdef EAP_AKA_PRIME
1619 int eap_peer_aka_prime_register(void)
1620 {
1621 	struct eap_method *eap;
1622 
1623 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1624 				    EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1625 				    "AKA'");
1626 	if (eap == NULL)
1627 		return -1;
1628 
1629 	eap->init = eap_aka_prime_init;
1630 	eap->deinit = eap_aka_deinit;
1631 	eap->process = eap_aka_process;
1632 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1633 	eap->getKey = eap_aka_getKey;
1634 	eap->getSessionId = eap_aka_get_session_id;
1635 	eap->has_reauth_data = eap_aka_has_reauth_data;
1636 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1637 	eap->init_for_reauth = eap_aka_init_for_reauth;
1638 	eap->get_identity = eap_aka_get_identity;
1639 	eap->get_emsk = eap_aka_get_emsk;
1640 	eap->get_error_code = eap_aka_get_error_code;
1641 
1642 	return eap_peer_method_register(eap);
1643 }
1644 #endif /* EAP_AKA_PRIME */
1645