eap_aka.c revision f21452aea786ac056eb01f1cbba4f553bd502747
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
22struct eap_aka_data {
23	u8 ik[EAP_AKA_IK_LEN], ck[EAP_AKA_CK_LEN], res[EAP_AKA_RES_MAX_LEN];
24	size_t res_len;
25	u8 nonce_s[EAP_SIM_NONCE_S_LEN];
26	u8 mk[EAP_SIM_MK_LEN];
27	u8 k_aut[EAP_AKA_PRIME_K_AUT_LEN];
28	u8 k_encr[EAP_SIM_K_ENCR_LEN];
29	u8 k_re[EAP_AKA_PRIME_K_RE_LEN]; /* EAP-AKA' only */
30	u8 msk[EAP_SIM_KEYING_DATA_LEN];
31	u8 emsk[EAP_EMSK_LEN];
32	u8 rand[EAP_AKA_RAND_LEN], autn[EAP_AKA_AUTN_LEN];
33	u8 auts[EAP_AKA_AUTS_LEN];
34
35	int num_id_req, num_notification;
36	u8 *pseudonym;
37	size_t pseudonym_len;
38	u8 *reauth_id;
39	size_t reauth_id_len;
40	int reauth;
41	unsigned int counter, counter_too_small;
42	u8 *last_eap_identity;
43	size_t last_eap_identity_len;
44	enum {
45		CONTINUE, RESULT_SUCCESS, RESULT_FAILURE, SUCCESS, FAILURE
46	} state;
47
48	struct wpabuf *id_msgs;
49	int prev_id;
50	int result_ind, use_result_ind;
51	u8 eap_method;
52	u8 *network_name;
53	size_t network_name_len;
54	u16 kdf;
55	int kdf_negotiation;
56};
57
58
59#ifndef CONFIG_NO_STDOUT_DEBUG
60static const char * eap_aka_state_txt(int state)
61{
62	switch (state) {
63	case CONTINUE:
64		return "CONTINUE";
65	case RESULT_SUCCESS:
66		return "RESULT_SUCCESS";
67	case RESULT_FAILURE:
68		return "RESULT_FAILURE";
69	case SUCCESS:
70		return "SUCCESS";
71	case FAILURE:
72		return "FAILURE";
73	default:
74		return "?";
75	}
76}
77#endif /* CONFIG_NO_STDOUT_DEBUG */
78
79
80static void eap_aka_state(struct eap_aka_data *data, int state)
81{
82	wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
83		   eap_aka_state_txt(data->state),
84		   eap_aka_state_txt(state));
85	data->state = state;
86}
87
88
89static void * eap_aka_init(struct eap_sm *sm)
90{
91	struct eap_aka_data *data;
92	const char *phase1 = eap_get_config_phase1(sm);
93	struct eap_peer_config *config = eap_get_config(sm);
94
95	data = os_zalloc(sizeof(*data));
96	if (data == NULL)
97		return NULL;
98
99	data->eap_method = EAP_TYPE_AKA;
100
101	eap_aka_state(data, CONTINUE);
102	data->prev_id = -1;
103
104	data->result_ind = phase1 && os_strstr(phase1, "result_ind=1") != NULL;
105
106	if (config && config->anonymous_identity) {
107		data->pseudonym = os_malloc(config->anonymous_identity_len);
108		if (data->pseudonym) {
109			os_memcpy(data->pseudonym, config->anonymous_identity,
110				  config->anonymous_identity_len);
111			data->pseudonym_len = config->anonymous_identity_len;
112		}
113	}
114
115	return data;
116}
117
118
119#ifdef EAP_AKA_PRIME
120static void * eap_aka_prime_init(struct eap_sm *sm)
121{
122	struct eap_aka_data *data = eap_aka_init(sm);
123	if (data == NULL)
124		return NULL;
125	data->eap_method = EAP_TYPE_AKA_PRIME;
126	return data;
127}
128#endif /* EAP_AKA_PRIME */
129
130
131static void eap_aka_deinit(struct eap_sm *sm, void *priv)
132{
133	struct eap_aka_data *data = priv;
134	if (data) {
135		os_free(data->pseudonym);
136		os_free(data->reauth_id);
137		os_free(data->last_eap_identity);
138		wpabuf_free(data->id_msgs);
139		os_free(data->network_name);
140		os_free(data);
141	}
142}
143
144
145static int eap_aka_ext_sim_req(struct eap_sm *sm, struct eap_aka_data *data)
146{
147	char req[200], *pos, *end;
148
149	wpa_printf(MSG_DEBUG, "EAP-AKA: Use external USIM processing");
150	pos = req;
151	end = pos + sizeof(req);
152	pos += os_snprintf(pos, end - pos, "UMTS-AUTH");
153	pos += os_snprintf(pos, end - pos, ":");
154	pos += wpa_snprintf_hex(pos, end - pos, data->rand, EAP_AKA_RAND_LEN);
155	pos += os_snprintf(pos, end - pos, ":");
156	pos += wpa_snprintf_hex(pos, end - pos, data->autn, EAP_AKA_AUTN_LEN);
157
158	eap_sm_request_sim(sm, req);
159	return 1;
160}
161
162
163static int eap_aka_ext_sim_result(struct eap_sm *sm, struct eap_aka_data *data,
164				  struct eap_peer_config *conf)
165{
166	char *resp, *pos;
167
168	wpa_printf(MSG_DEBUG,
169		   "EAP-AKA: Use result from external USIM processing");
170
171	resp = conf->external_sim_resp;
172	conf->external_sim_resp = NULL;
173
174	if (os_strncmp(resp, "UMTS-AUTS:", 10) == 0) {
175		pos = resp + 10;
176		if (hexstr2bin(pos, data->auts, EAP_AKA_AUTS_LEN) < 0)
177			goto invalid;
178		wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: AUTS", data->auts,
179				EAP_AKA_AUTS_LEN);
180		os_free(resp);
181		return -2;
182	}
183
184	if (os_strncmp(resp, "UMTS-AUTH:", 10) != 0) {
185		wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized external USIM processing response");
186		os_free(resp);
187		return -1;
188	}
189
190	pos = resp + 10;
191	wpa_hexdump(MSG_DEBUG, "EAP-AKA: RAND", data->rand, EAP_AKA_RAND_LEN);
192
193	if (hexstr2bin(pos, data->ik, EAP_AKA_IK_LEN) < 0)
194		goto invalid;
195	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", data->ik, EAP_AKA_IK_LEN);
196	pos += EAP_AKA_IK_LEN * 2;
197	if (*pos != ':')
198		goto invalid;
199	pos++;
200
201	if (hexstr2bin(pos, data->ck, EAP_AKA_CK_LEN) < 0)
202		goto invalid;
203	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", data->ck, EAP_AKA_CK_LEN);
204	pos += EAP_AKA_CK_LEN * 2;
205	if (*pos != ':')
206		goto invalid;
207	pos++;
208
209	data->res_len = os_strlen(pos) / 2;
210	if (data->res_len > EAP_AKA_RES_MAX_LEN) {
211		data->res_len = 0;
212		goto invalid;
213	}
214	if (hexstr2bin(pos, data->res, data->res_len) < 0)
215		goto invalid;
216	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: RES", data->res, data->res_len);
217
218	os_free(resp);
219	return 0;
220
221invalid:
222	wpa_printf(MSG_DEBUG, "EAP-AKA: Invalid external USIM processing UMTS-AUTH response");
223	os_free(resp);
224	return -1;
225}
226
227
228static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data)
229{
230	struct eap_peer_config *conf;
231
232	wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm");
233
234	conf = eap_get_config(sm);
235	if (conf == NULL)
236		return -1;
237
238	if (sm->external_sim) {
239		if (conf->external_sim_resp)
240			return eap_aka_ext_sim_result(sm, data, conf);
241		else
242			return eap_aka_ext_sim_req(sm, data);
243	}
244
245	if (conf->pcsc) {
246		return scard_umts_auth(sm->scard_ctx, data->rand,
247				       data->autn, data->res, &data->res_len,
248				       data->ik, data->ck, data->auts);
249	}
250
251#ifdef CONFIG_USIM_SIMULATOR
252	if (conf->password) {
253		u8 opc[16], k[16], sqn[6];
254		const char *pos;
255		wpa_printf(MSG_DEBUG, "EAP-AKA: Use internal Milenage "
256			   "implementation for UMTS authentication");
257		if (conf->password_len < 78) {
258			wpa_printf(MSG_DEBUG, "EAP-AKA: invalid Milenage "
259				   "password");
260			return -1;
261		}
262		pos = (const char *) conf->password;
263		if (hexstr2bin(pos, k, 16))
264			return -1;
265		pos += 32;
266		if (*pos != ':')
267			return -1;
268		pos++;
269
270		if (hexstr2bin(pos, opc, 16))
271			return -1;
272		pos += 32;
273		if (*pos != ':')
274			return -1;
275		pos++;
276
277		if (hexstr2bin(pos, sqn, 6))
278			return -1;
279
280		return milenage_check(opc, k, sqn, data->rand, data->autn,
281				      data->ik, data->ck,
282				      data->res, &data->res_len, data->auts);
283	}
284#endif /* CONFIG_USIM_SIMULATOR */
285
286#ifdef CONFIG_USIM_HARDCODED
287	wpa_printf(MSG_DEBUG, "EAP-AKA: Use hardcoded Kc and SRES values for "
288		   "testing");
289
290	/* These hardcoded Kc and SRES values are used for testing.
291	 * Could consider making them configurable. */
292	os_memset(data->res, '2', EAP_AKA_RES_MAX_LEN);
293	data->res_len = EAP_AKA_RES_MAX_LEN;
294	os_memset(data->ik, '3', EAP_AKA_IK_LEN);
295	os_memset(data->ck, '4', EAP_AKA_CK_LEN);
296	{
297		u8 autn[EAP_AKA_AUTN_LEN];
298		os_memset(autn, '1', EAP_AKA_AUTN_LEN);
299		if (os_memcmp(autn, data->autn, EAP_AKA_AUTN_LEN) != 0) {
300			wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match "
301				   "with expected value");
302			return -1;
303		}
304	}
305#if 0
306	{
307		static int test_resync = 1;
308		if (test_resync) {
309			/* Test Resynchronization */
310			test_resync = 0;
311			return -2;
312		}
313	}
314#endif
315	return 0;
316
317#else /* CONFIG_USIM_HARDCODED */
318
319	wpa_printf(MSG_DEBUG, "EAP-AKA: No UMTS authentication algorithm "
320		   "enabled");
321	return -1;
322
323#endif /* CONFIG_USIM_HARDCODED */
324}
325
326
327#define CLEAR_PSEUDONYM	0x01
328#define CLEAR_REAUTH_ID	0x02
329#define CLEAR_EAP_ID	0x04
330
331static void eap_aka_clear_identities(struct eap_sm *sm,
332				     struct eap_aka_data *data, int id)
333{
334	if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
335		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old pseudonym");
336		os_free(data->pseudonym);
337		data->pseudonym = NULL;
338		data->pseudonym_len = 0;
339		eap_set_anon_id(sm, NULL, 0);
340	}
341	if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
342		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old reauth_id");
343		os_free(data->reauth_id);
344		data->reauth_id = NULL;
345		data->reauth_id_len = 0;
346	}
347	if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
348		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old eap_id");
349		os_free(data->last_eap_identity);
350		data->last_eap_identity = NULL;
351		data->last_eap_identity_len = 0;
352	}
353}
354
355
356static int eap_aka_learn_ids(struct eap_sm *sm, struct eap_aka_data *data,
357			     struct eap_sim_attrs *attr)
358{
359	if (attr->next_pseudonym) {
360		const u8 *identity = NULL;
361		size_t identity_len = 0;
362		const u8 *realm = NULL;
363		size_t realm_len = 0;
364
365		wpa_hexdump_ascii(MSG_DEBUG,
366				  "EAP-AKA: (encr) AT_NEXT_PSEUDONYM",
367				  attr->next_pseudonym,
368				  attr->next_pseudonym_len);
369		os_free(data->pseudonym);
370		/* Look for the realm of the permanent identity */
371		identity = eap_get_config_identity(sm, &identity_len);
372		if (identity) {
373			for (realm = identity, realm_len = identity_len;
374			     realm_len > 0; realm_len--, realm++) {
375				if (*realm == '@')
376					break;
377			}
378		}
379		data->pseudonym = os_malloc(attr->next_pseudonym_len +
380					    realm_len);
381		if (data->pseudonym == NULL) {
382			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
383				   "next pseudonym");
384			data->pseudonym_len = 0;
385			return -1;
386		}
387		os_memcpy(data->pseudonym, attr->next_pseudonym,
388			  attr->next_pseudonym_len);
389		if (realm_len) {
390			os_memcpy(data->pseudonym + attr->next_pseudonym_len,
391				  realm, realm_len);
392		}
393		data->pseudonym_len = attr->next_pseudonym_len + realm_len;
394		eap_set_anon_id(sm, data->pseudonym, data->pseudonym_len);
395	}
396
397	if (attr->next_reauth_id) {
398		os_free(data->reauth_id);
399		data->reauth_id = os_malloc(attr->next_reauth_id_len);
400		if (data->reauth_id == NULL) {
401			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
402				   "next reauth_id");
403			data->reauth_id_len = 0;
404			return -1;
405		}
406		os_memcpy(data->reauth_id, attr->next_reauth_id,
407			  attr->next_reauth_id_len);
408		data->reauth_id_len = attr->next_reauth_id_len;
409		wpa_hexdump_ascii(MSG_DEBUG,
410				  "EAP-AKA: (encr) AT_NEXT_REAUTH_ID",
411				  data->reauth_id,
412				  data->reauth_id_len);
413	}
414
415	return 0;
416}
417
418
419static int eap_aka_add_id_msg(struct eap_aka_data *data,
420			      const struct wpabuf *msg)
421{
422	if (msg == NULL)
423		return -1;
424
425	if (data->id_msgs == NULL) {
426		data->id_msgs = wpabuf_dup(msg);
427		return data->id_msgs == NULL ? -1 : 0;
428	}
429
430	if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
431		return -1;
432	wpabuf_put_buf(data->id_msgs, msg);
433
434	return 0;
435}
436
437
438static void eap_aka_add_checkcode(struct eap_aka_data *data,
439				  struct eap_sim_msg *msg)
440{
441	const u8 *addr;
442	size_t len;
443	u8 hash[SHA256_MAC_LEN];
444
445	wpa_printf(MSG_DEBUG, "   AT_CHECKCODE");
446
447	if (data->id_msgs == NULL) {
448		/*
449		 * No EAP-AKA/Identity packets were exchanged - send empty
450		 * checkcode.
451		 */
452		eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
453		return;
454	}
455
456	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
457	addr = wpabuf_head(data->id_msgs);
458	len = wpabuf_len(data->id_msgs);
459	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
460#ifdef EAP_AKA_PRIME
461	if (data->eap_method == EAP_TYPE_AKA_PRIME)
462		sha256_vector(1, &addr, &len, hash);
463	else
464#endif /* EAP_AKA_PRIME */
465		sha1_vector(1, &addr, &len, hash);
466
467	eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
468			data->eap_method == EAP_TYPE_AKA_PRIME ?
469			EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
470}
471
472
473static int eap_aka_verify_checkcode(struct eap_aka_data *data,
474				    const u8 *checkcode, size_t checkcode_len)
475{
476	const u8 *addr;
477	size_t len;
478	u8 hash[SHA256_MAC_LEN];
479	size_t hash_len;
480
481	if (checkcode == NULL)
482		return -1;
483
484	if (data->id_msgs == NULL) {
485		if (checkcode_len != 0) {
486			wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
487				   "indicates that AKA/Identity messages were "
488				   "used, but they were not");
489			return -1;
490		}
491		return 0;
492	}
493
494	hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
495		EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
496
497	if (checkcode_len != hash_len) {
498		wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
499			   "indicates that AKA/Identity message were not "
500			   "used, but they were");
501		return -1;
502	}
503
504	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
505	addr = wpabuf_head(data->id_msgs);
506	len = wpabuf_len(data->id_msgs);
507#ifdef EAP_AKA_PRIME
508	if (data->eap_method == EAP_TYPE_AKA_PRIME)
509		sha256_vector(1, &addr, &len, hash);
510	else
511#endif /* EAP_AKA_PRIME */
512		sha1_vector(1, &addr, &len, hash);
513
514	if (os_memcmp(hash, checkcode, hash_len) != 0) {
515		wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
516		return -1;
517	}
518
519	return 0;
520}
521
522
523static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
524					    int err)
525{
526	struct eap_sim_msg *msg;
527
528	eap_aka_state(data, FAILURE);
529	data->num_id_req = 0;
530	data->num_notification = 0;
531
532	wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
533		   err);
534	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
535			       EAP_AKA_SUBTYPE_CLIENT_ERROR);
536	eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
537	return eap_sim_msg_finish(msg, NULL, NULL, 0);
538}
539
540
541static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
542						     u8 id)
543{
544	struct eap_sim_msg *msg;
545
546	eap_aka_state(data, FAILURE);
547	data->num_id_req = 0;
548	data->num_notification = 0;
549
550	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
551		   "(id=%d)", id);
552	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
553			       EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
554	return eap_sim_msg_finish(msg, NULL, NULL, 0);
555}
556
557
558static struct wpabuf * eap_aka_synchronization_failure(
559	struct eap_aka_data *data, u8 id)
560{
561	struct eap_sim_msg *msg;
562
563	data->num_id_req = 0;
564	data->num_notification = 0;
565
566	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
567		   "(id=%d)", id);
568	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
569			       EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
570	wpa_printf(MSG_DEBUG, "   AT_AUTS");
571	eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
572			     EAP_AKA_AUTS_LEN);
573	return eap_sim_msg_finish(msg, NULL, NULL, 0);
574}
575
576
577static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
578						 struct eap_aka_data *data,
579						 u8 id,
580						 enum eap_sim_id_req id_req)
581{
582	const u8 *identity = NULL;
583	size_t identity_len = 0;
584	struct eap_sim_msg *msg;
585
586	data->reauth = 0;
587	if (id_req == ANY_ID && data->reauth_id) {
588		identity = data->reauth_id;
589		identity_len = data->reauth_id_len;
590		data->reauth = 1;
591	} else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
592		   data->pseudonym) {
593		identity = data->pseudonym;
594		identity_len = data->pseudonym_len;
595		eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
596	} else if (id_req != NO_ID_REQ) {
597		identity = eap_get_config_identity(sm, &identity_len);
598		if (identity) {
599			eap_aka_clear_identities(sm, data, CLEAR_PSEUDONYM |
600						 CLEAR_REAUTH_ID);
601		}
602	}
603	if (id_req != NO_ID_REQ)
604		eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
605
606	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
607	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
608			       EAP_AKA_SUBTYPE_IDENTITY);
609
610	if (identity) {
611		wpa_hexdump_ascii(MSG_DEBUG, "   AT_IDENTITY",
612				  identity, identity_len);
613		eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
614				identity, identity_len);
615	}
616
617	return eap_sim_msg_finish(msg, NULL, NULL, 0);
618}
619
620
621static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
622						  u8 id)
623{
624	struct eap_sim_msg *msg;
625
626	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
627	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
628			       EAP_AKA_SUBTYPE_CHALLENGE);
629	wpa_printf(MSG_DEBUG, "   AT_RES");
630	eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
631			data->res, data->res_len);
632	eap_aka_add_checkcode(data, msg);
633	if (data->use_result_ind) {
634		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
635		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
636	}
637	wpa_printf(MSG_DEBUG, "   AT_MAC");
638	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
639	return eap_sim_msg_finish(msg, data->k_aut, (u8 *) "", 0);
640}
641
642
643static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
644					       u8 id, int counter_too_small,
645					       const u8 *nonce_s)
646{
647	struct eap_sim_msg *msg;
648	unsigned int counter;
649
650	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
651		   id);
652	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
653			       EAP_AKA_SUBTYPE_REAUTHENTICATION);
654	wpa_printf(MSG_DEBUG, "   AT_IV");
655	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
656	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
657
658	if (counter_too_small) {
659		wpa_printf(MSG_DEBUG, "   *AT_COUNTER_TOO_SMALL");
660		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
661		counter = data->counter_too_small;
662	} else
663		counter = data->counter;
664
665	wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", counter);
666	eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
667
668	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
669		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
670			   "AT_ENCR_DATA");
671		eap_sim_msg_free(msg);
672		return NULL;
673	}
674	eap_aka_add_checkcode(data, msg);
675	if (data->use_result_ind) {
676		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
677		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
678	}
679	wpa_printf(MSG_DEBUG, "   AT_MAC");
680	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
681	return eap_sim_msg_finish(msg, data->k_aut, nonce_s,
682				  EAP_SIM_NONCE_S_LEN);
683}
684
685
686static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
687						     u8 id, u16 notification)
688{
689	struct eap_sim_msg *msg;
690	u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
691
692	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
693	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
694			       EAP_AKA_SUBTYPE_NOTIFICATION);
695	if (k_aut && data->reauth) {
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,
699					   EAP_SIM_AT_ENCR_DATA);
700		wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", data->counter);
701		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
702				NULL, 0);
703		if (eap_sim_msg_add_encr_end(msg, data->k_encr,
704					     EAP_SIM_AT_PADDING)) {
705			wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
706				   "AT_ENCR_DATA");
707			eap_sim_msg_free(msg);
708			return NULL;
709		}
710	}
711	if (k_aut) {
712		wpa_printf(MSG_DEBUG, "   AT_MAC");
713		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
714	}
715	return eap_sim_msg_finish(msg, k_aut, (u8 *) "", 0);
716}
717
718
719static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
720						struct eap_aka_data *data,
721						u8 id,
722						const struct wpabuf *reqData,
723						struct eap_sim_attrs *attr)
724{
725	int id_error;
726	struct wpabuf *buf;
727
728	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
729
730	id_error = 0;
731	switch (attr->id_req) {
732	case NO_ID_REQ:
733		break;
734	case ANY_ID:
735		if (data->num_id_req > 0)
736			id_error++;
737		data->num_id_req++;
738		break;
739	case FULLAUTH_ID:
740		if (data->num_id_req > 1)
741			id_error++;
742		data->num_id_req++;
743		break;
744	case PERMANENT_ID:
745		if (data->num_id_req > 2)
746			id_error++;
747		data->num_id_req++;
748		break;
749	}
750	if (id_error) {
751		wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
752			   "used within one authentication");
753		return eap_aka_client_error(data, id,
754					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
755	}
756
757	buf = eap_aka_response_identity(sm, data, id, attr->id_req);
758
759	if (data->prev_id != id) {
760		eap_aka_add_id_msg(data, reqData);
761		eap_aka_add_id_msg(data, buf);
762		data->prev_id = id;
763	}
764
765	return buf;
766}
767
768
769static int eap_aka_verify_mac(struct eap_aka_data *data,
770			      const struct wpabuf *req,
771			      const u8 *mac, const u8 *extra,
772			      size_t extra_len)
773{
774	if (data->eap_method == EAP_TYPE_AKA_PRIME)
775		return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
776						 extra_len);
777	return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
778}
779
780
781#ifdef EAP_AKA_PRIME
782static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
783						u8 id, u16 kdf)
784{
785	struct eap_sim_msg *msg;
786
787	data->kdf_negotiation = 1;
788	data->kdf = kdf;
789	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
790		   "select)", id);
791	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
792			       EAP_AKA_SUBTYPE_CHALLENGE);
793	wpa_printf(MSG_DEBUG, "   AT_KDF");
794	eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
795	return eap_sim_msg_finish(msg, NULL, NULL, 0);
796}
797
798
799static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
800					     u8 id, struct eap_sim_attrs *attr)
801{
802	size_t i;
803
804	for (i = 0; i < attr->kdf_count; i++) {
805		if (attr->kdf[i] == EAP_AKA_PRIME_KDF)
806			return eap_aka_prime_kdf_select(data, id,
807							EAP_AKA_PRIME_KDF);
808	}
809
810	/* No matching KDF found - fail authentication as if AUTN had been
811	 * incorrect */
812	return eap_aka_authentication_reject(data, id);
813}
814
815
816static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
817				   struct eap_sim_attrs *attr)
818{
819	size_t i, j;
820
821	if (attr->kdf_count == 0)
822		return 0;
823
824	/* The only allowed (and required) duplication of a KDF is the addition
825	 * of the selected KDF into the beginning of the list. */
826
827	if (data->kdf_negotiation) {
828		if (attr->kdf[0] != data->kdf) {
829			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
830				   "accept the selected KDF");
831			return 0;
832		}
833
834		for (i = 1; i < attr->kdf_count; i++) {
835			if (attr->kdf[i] == data->kdf)
836				break;
837		}
838		if (i == attr->kdf_count &&
839		    attr->kdf_count < EAP_AKA_PRIME_KDF_MAX) {
840			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
841				   "duplicate the selected KDF");
842			return 0;
843		}
844
845		/* TODO: should check that the list is identical to the one
846		 * used in the previous Challenge message apart from the added
847		 * entry in the beginning. */
848	}
849
850	for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
851		for (j = i + 1; j < attr->kdf_count; j++) {
852			if (attr->kdf[i] == attr->kdf[j]) {
853				wpa_printf(MSG_WARNING, "EAP-AKA': The server "
854					   "included a duplicated KDF");
855				return 0;
856			}
857		}
858	}
859
860	return 1;
861}
862#endif /* EAP_AKA_PRIME */
863
864
865static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
866						 struct eap_aka_data *data,
867						 u8 id,
868						 const struct wpabuf *reqData,
869						 struct eap_sim_attrs *attr)
870{
871	const u8 *identity;
872	size_t identity_len;
873	int res;
874	struct eap_sim_attrs eattr;
875
876	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
877
878	if (attr->checkcode &&
879	    eap_aka_verify_checkcode(data, attr->checkcode,
880				     attr->checkcode_len)) {
881		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
882			   "message");
883		return eap_aka_client_error(data, id,
884					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
885	}
886
887#ifdef EAP_AKA_PRIME
888	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
889		if (!attr->kdf_input || attr->kdf_input_len == 0) {
890			wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
891				   "did not include non-empty AT_KDF_INPUT");
892			/* Fail authentication as if AUTN had been incorrect */
893			return eap_aka_authentication_reject(data, id);
894		}
895		os_free(data->network_name);
896		data->network_name = os_malloc(attr->kdf_input_len);
897		if (data->network_name == NULL) {
898			wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
899				   "storing Network Name");
900			return eap_aka_authentication_reject(data, id);
901		}
902		os_memcpy(data->network_name, attr->kdf_input,
903			  attr->kdf_input_len);
904		data->network_name_len = attr->kdf_input_len;
905		wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
906				  "(AT_KDF_INPUT)",
907				  data->network_name, data->network_name_len);
908		/* TODO: check Network Name per 3GPP.33.402 */
909
910		if (!eap_aka_prime_kdf_valid(data, attr))
911			return eap_aka_authentication_reject(data, id);
912
913		if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
914			return eap_aka_prime_kdf_neg(data, id, attr);
915
916		data->kdf = EAP_AKA_PRIME_KDF;
917		wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
918	}
919
920	if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
921		u16 flags = WPA_GET_BE16(attr->bidding);
922		if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
923		    eap_allowed_method(sm, EAP_VENDOR_IETF,
924				       EAP_TYPE_AKA_PRIME)) {
925			wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
926				   "AKA' to AKA detected");
927			/* Fail authentication as if AUTN had been incorrect */
928			return eap_aka_authentication_reject(data, id);
929		}
930	}
931#endif /* EAP_AKA_PRIME */
932
933	data->reauth = 0;
934	if (!attr->mac || !attr->rand || !attr->autn) {
935		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
936			   "did not include%s%s%s",
937			   !attr->mac ? " AT_MAC" : "",
938			   !attr->rand ? " AT_RAND" : "",
939			   !attr->autn ? " AT_AUTN" : "");
940		return eap_aka_client_error(data, id,
941					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
942	}
943	os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
944	os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
945
946	res = eap_aka_umts_auth(sm, data);
947	if (res == -1) {
948		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
949			   "failed (AUTN)");
950		return eap_aka_authentication_reject(data, id);
951	} else if (res == -2) {
952		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
953			   "failed (AUTN seq# -> AUTS)");
954		return eap_aka_synchronization_failure(data, id);
955	} else if (res > 0) {
956		wpa_printf(MSG_DEBUG, "EAP-AKA: Wait for external USIM processing");
957		return NULL;
958	} else if (res) {
959		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
960		return eap_aka_client_error(data, id,
961					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
962	}
963#ifdef EAP_AKA_PRIME
964	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
965		/* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
966		 * needed 6-octet SQN ^ AK for CK',IK' derivation */
967		u16 amf = WPA_GET_BE16(data->autn + 6);
968		if (!(amf & 0x8000)) {
969			wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
970				   "not set (AMF=0x%4x)", amf);
971			return eap_aka_authentication_reject(data, id);
972		}
973		eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
974						 data->autn,
975						 data->network_name,
976						 data->network_name_len);
977	}
978#endif /* EAP_AKA_PRIME */
979	if (data->last_eap_identity) {
980		identity = data->last_eap_identity;
981		identity_len = data->last_eap_identity_len;
982	} else if (data->pseudonym) {
983		identity = data->pseudonym;
984		identity_len = data->pseudonym_len;
985	} else
986		identity = eap_get_config_identity(sm, &identity_len);
987	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
988			  "derivation", identity, identity_len);
989	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
990		eap_aka_prime_derive_keys(identity, identity_len, data->ik,
991					  data->ck, data->k_encr, data->k_aut,
992					  data->k_re, data->msk, data->emsk);
993	} else {
994		eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
995				  data->mk);
996		eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
997				    data->msk, data->emsk);
998	}
999	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1000		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
1001			   "used invalid AT_MAC");
1002		return eap_aka_client_error(data, id,
1003					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1004	}
1005
1006	/* Old reauthentication identity must not be used anymore. In
1007	 * other words, if no new identities are received, full
1008	 * authentication will be used on next reauthentication (using
1009	 * pseudonym identity or permanent identity). */
1010	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1011
1012	if (attr->encr_data) {
1013		u8 *decrypted;
1014		decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1015					       attr->encr_data_len, attr->iv,
1016					       &eattr, 0);
1017		if (decrypted == NULL) {
1018			return eap_aka_client_error(
1019				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1020		}
1021		eap_aka_learn_ids(sm, data, &eattr);
1022		os_free(decrypted);
1023	}
1024
1025	if (data->result_ind && attr->result_ind)
1026		data->use_result_ind = 1;
1027
1028	if (data->state != FAILURE && data->state != RESULT_FAILURE) {
1029		eap_aka_state(data, data->use_result_ind ?
1030			      RESULT_SUCCESS : SUCCESS);
1031	}
1032
1033	data->num_id_req = 0;
1034	data->num_notification = 0;
1035	/* RFC 4187 specifies that counter is initialized to one after
1036	 * fullauth, but initializing it to zero makes it easier to implement
1037	 * reauth verification. */
1038	data->counter = 0;
1039	return eap_aka_response_challenge(data, id);
1040}
1041
1042
1043static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
1044					       struct eap_sim_attrs *attr)
1045{
1046	struct eap_sim_attrs eattr;
1047	u8 *decrypted;
1048
1049	if (attr->encr_data == NULL || attr->iv == NULL) {
1050		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
1051			   "reauth did not include encrypted data");
1052		return -1;
1053	}
1054
1055	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1056				       attr->encr_data_len, attr->iv, &eattr,
1057				       0);
1058	if (decrypted == NULL) {
1059		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1060			   "data from notification message");
1061		return -1;
1062	}
1063
1064	if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
1065		wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
1066			   "message does not match with counter in reauth "
1067			   "message");
1068		os_free(decrypted);
1069		return -1;
1070	}
1071
1072	os_free(decrypted);
1073	return 0;
1074}
1075
1076
1077static int eap_aka_process_notification_auth(struct eap_aka_data *data,
1078					     const struct wpabuf *reqData,
1079					     struct eap_sim_attrs *attr)
1080{
1081	if (attr->mac == NULL) {
1082		wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
1083			   "Notification message");
1084		return -1;
1085	}
1086
1087	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1088		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
1089			   "used invalid AT_MAC");
1090		return -1;
1091	}
1092
1093	if (data->reauth &&
1094	    eap_aka_process_notification_reauth(data, attr)) {
1095		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
1096			   "message after reauth");
1097		return -1;
1098	}
1099
1100	return 0;
1101}
1102
1103
1104static struct wpabuf * eap_aka_process_notification(
1105	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1106	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1107{
1108	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
1109	if (data->num_notification > 0) {
1110		wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
1111			   "rounds (only one allowed)");
1112		return eap_aka_client_error(data, id,
1113					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1114	}
1115	data->num_notification++;
1116	if (attr->notification == -1) {
1117		wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
1118			   "Notification message");
1119		return eap_aka_client_error(data, id,
1120					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1121	}
1122
1123	if ((attr->notification & 0x4000) == 0 &&
1124	    eap_aka_process_notification_auth(data, reqData, attr)) {
1125		return eap_aka_client_error(data, id,
1126					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1127	}
1128
1129	eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
1130	if (attr->notification >= 0 && attr->notification < 32768) {
1131		eap_aka_state(data, FAILURE);
1132	} else if (attr->notification == EAP_SIM_SUCCESS &&
1133		   data->state == RESULT_SUCCESS)
1134		eap_aka_state(data, SUCCESS);
1135	return eap_aka_response_notification(data, id, attr->notification);
1136}
1137
1138
1139static struct wpabuf * eap_aka_process_reauthentication(
1140	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1141	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1142{
1143	struct eap_sim_attrs eattr;
1144	u8 *decrypted;
1145
1146	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
1147
1148	if (attr->checkcode &&
1149	    eap_aka_verify_checkcode(data, attr->checkcode,
1150				     attr->checkcode_len)) {
1151		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
1152			   "message");
1153		return eap_aka_client_error(data, id,
1154					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1155	}
1156
1157	if (data->reauth_id == NULL) {
1158		wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
1159			   "reauthentication, but no reauth_id available");
1160		return eap_aka_client_error(data, id,
1161					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1162	}
1163
1164	data->reauth = 1;
1165	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1166		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1167			   "did not have valid AT_MAC");
1168		return eap_aka_client_error(data, id,
1169					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1170	}
1171
1172	if (attr->encr_data == NULL || attr->iv == NULL) {
1173		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1174			   "message did not include encrypted data");
1175		return eap_aka_client_error(data, id,
1176					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1177	}
1178
1179	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1180				       attr->encr_data_len, attr->iv, &eattr,
1181				       0);
1182	if (decrypted == NULL) {
1183		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1184			   "data from reauthentication message");
1185		return eap_aka_client_error(data, id,
1186					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1187	}
1188
1189	if (eattr.nonce_s == NULL || eattr.counter < 0) {
1190		wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
1191			   !eattr.nonce_s ? " AT_NONCE_S" : "",
1192			   eattr.counter < 0 ? " AT_COUNTER" : "");
1193		os_free(decrypted);
1194		return eap_aka_client_error(data, id,
1195					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1196	}
1197
1198	if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1199		struct wpabuf *res;
1200		wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
1201			   "(%d <= %d)", eattr.counter, data->counter);
1202		data->counter_too_small = eattr.counter;
1203
1204		/* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1205		 * reauth_id must not be used to start a new reauthentication.
1206		 * However, since it was used in the last EAP-Response-Identity
1207		 * packet, it has to saved for the following fullauth to be
1208		 * used in MK derivation. */
1209		os_free(data->last_eap_identity);
1210		data->last_eap_identity = data->reauth_id;
1211		data->last_eap_identity_len = data->reauth_id_len;
1212		data->reauth_id = NULL;
1213		data->reauth_id_len = 0;
1214
1215		res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
1216		os_free(decrypted);
1217
1218		return res;
1219	}
1220	data->counter = eattr.counter;
1221
1222	os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1223	wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
1224		    data->nonce_s, EAP_SIM_NONCE_S_LEN);
1225
1226	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1227		eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
1228						 data->reauth_id,
1229						 data->reauth_id_len,
1230						 data->nonce_s,
1231						 data->msk, data->emsk);
1232	} else {
1233		eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
1234					   data->reauth_id_len,
1235					   data->nonce_s, data->mk,
1236					   data->msk, data->emsk);
1237	}
1238	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1239	eap_aka_learn_ids(sm, data, &eattr);
1240
1241	if (data->result_ind && attr->result_ind)
1242		data->use_result_ind = 1;
1243
1244	if (data->state != FAILURE && data->state != RESULT_FAILURE) {
1245		eap_aka_state(data, data->use_result_ind ?
1246			      RESULT_SUCCESS : SUCCESS);
1247	}
1248
1249	data->num_id_req = 0;
1250	data->num_notification = 0;
1251	if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
1252		wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
1253			   "fast reauths performed - force fullauth");
1254		eap_aka_clear_identities(sm, data,
1255					 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1256	}
1257	os_free(decrypted);
1258	return eap_aka_response_reauth(data, id, 0, data->nonce_s);
1259}
1260
1261
1262static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
1263				       struct eap_method_ret *ret,
1264				       const struct wpabuf *reqData)
1265{
1266	struct eap_aka_data *data = priv;
1267	const struct eap_hdr *req;
1268	u8 subtype, id;
1269	struct wpabuf *res;
1270	const u8 *pos;
1271	struct eap_sim_attrs attr;
1272	size_t len;
1273
1274	wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
1275	if (eap_get_config_identity(sm, &len) == NULL) {
1276		wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
1277		eap_sm_request_identity(sm);
1278		ret->ignore = TRUE;
1279		return NULL;
1280	}
1281
1282	pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
1283			       &len);
1284	if (pos == NULL || len < 1) {
1285		ret->ignore = TRUE;
1286		return NULL;
1287	}
1288	req = wpabuf_head(reqData);
1289	id = req->identifier;
1290	len = be_to_host16(req->length);
1291
1292	ret->ignore = FALSE;
1293	ret->methodState = METHOD_MAY_CONT;
1294	ret->decision = DECISION_FAIL;
1295	ret->allowNotifications = TRUE;
1296
1297	subtype = *pos++;
1298	wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
1299	pos += 2; /* Reserved */
1300
1301	if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
1302			       data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1303			       0)) {
1304		res = eap_aka_client_error(data, id,
1305					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1306		goto done;
1307	}
1308
1309	switch (subtype) {
1310	case EAP_AKA_SUBTYPE_IDENTITY:
1311		res = eap_aka_process_identity(sm, data, id, reqData, &attr);
1312		break;
1313	case EAP_AKA_SUBTYPE_CHALLENGE:
1314		res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
1315		break;
1316	case EAP_AKA_SUBTYPE_NOTIFICATION:
1317		res = eap_aka_process_notification(sm, data, id, reqData,
1318						   &attr);
1319		break;
1320	case EAP_AKA_SUBTYPE_REAUTHENTICATION:
1321		res = eap_aka_process_reauthentication(sm, data, id, reqData,
1322						       &attr);
1323		break;
1324	case EAP_AKA_SUBTYPE_CLIENT_ERROR:
1325		wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
1326		res = eap_aka_client_error(data, id,
1327					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1328		break;
1329	default:
1330		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
1331		res = eap_aka_client_error(data, id,
1332					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1333		break;
1334	}
1335
1336done:
1337	if (data->state == FAILURE) {
1338		ret->decision = DECISION_FAIL;
1339		ret->methodState = METHOD_DONE;
1340	} else if (data->state == SUCCESS) {
1341		ret->decision = data->use_result_ind ?
1342			DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1343		/*
1344		 * It is possible for the server to reply with AKA
1345		 * Notification, so we must allow the method to continue and
1346		 * not only accept EAP-Success at this point.
1347		 */
1348		ret->methodState = data->use_result_ind ?
1349			METHOD_DONE : METHOD_MAY_CONT;
1350	} else if (data->state == RESULT_FAILURE)
1351		ret->methodState = METHOD_CONT;
1352	else if (data->state == RESULT_SUCCESS)
1353		ret->methodState = METHOD_CONT;
1354
1355	if (ret->methodState == METHOD_DONE) {
1356		ret->allowNotifications = FALSE;
1357	}
1358
1359	return res;
1360}
1361
1362
1363static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
1364{
1365	struct eap_aka_data *data = priv;
1366	return data->pseudonym || data->reauth_id;
1367}
1368
1369
1370static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
1371{
1372	struct eap_aka_data *data = priv;
1373	eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
1374	data->prev_id = -1;
1375	wpabuf_free(data->id_msgs);
1376	data->id_msgs = NULL;
1377	data->use_result_ind = 0;
1378	data->kdf_negotiation = 0;
1379}
1380
1381
1382static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
1383{
1384	struct eap_aka_data *data = priv;
1385	data->num_id_req = 0;
1386	data->num_notification = 0;
1387	eap_aka_state(data, CONTINUE);
1388	return priv;
1389}
1390
1391
1392static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
1393				       size_t *len)
1394{
1395	struct eap_aka_data *data = priv;
1396
1397	if (data->reauth_id) {
1398		*len = data->reauth_id_len;
1399		return data->reauth_id;
1400	}
1401
1402	if (data->pseudonym) {
1403		*len = data->pseudonym_len;
1404		return data->pseudonym;
1405	}
1406
1407	return NULL;
1408}
1409
1410
1411static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
1412{
1413	struct eap_aka_data *data = priv;
1414	return data->state == SUCCESS;
1415}
1416
1417
1418static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1419{
1420	struct eap_aka_data *data = priv;
1421	u8 *key;
1422
1423	if (data->state != SUCCESS)
1424		return NULL;
1425
1426	key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
1427	if (key == NULL)
1428		return NULL;
1429
1430	*len = EAP_SIM_KEYING_DATA_LEN;
1431	os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
1432
1433	return key;
1434}
1435
1436
1437static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1438{
1439	struct eap_aka_data *data = priv;
1440	u8 *id;
1441
1442	if (data->state != SUCCESS)
1443		return NULL;
1444
1445	*len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1446	id = os_malloc(*len);
1447	if (id == NULL)
1448		return NULL;
1449
1450	id[0] = data->eap_method;
1451	os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1452	os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn, EAP_AKA_AUTN_LEN);
1453	wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1454
1455	return id;
1456}
1457
1458
1459static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1460{
1461	struct eap_aka_data *data = priv;
1462	u8 *key;
1463
1464	if (data->state != SUCCESS)
1465		return NULL;
1466
1467	key = os_malloc(EAP_EMSK_LEN);
1468	if (key == NULL)
1469		return NULL;
1470
1471	*len = EAP_EMSK_LEN;
1472	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
1473
1474	return key;
1475}
1476
1477
1478int eap_peer_aka_register(void)
1479{
1480	struct eap_method *eap;
1481	int ret;
1482
1483	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1484				    EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1485	if (eap == NULL)
1486		return -1;
1487
1488	eap->init = eap_aka_init;
1489	eap->deinit = eap_aka_deinit;
1490	eap->process = eap_aka_process;
1491	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1492	eap->getKey = eap_aka_getKey;
1493	eap->getSessionId = eap_aka_get_session_id;
1494	eap->has_reauth_data = eap_aka_has_reauth_data;
1495	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1496	eap->init_for_reauth = eap_aka_init_for_reauth;
1497	eap->get_identity = eap_aka_get_identity;
1498	eap->get_emsk = eap_aka_get_emsk;
1499
1500	ret = eap_peer_method_register(eap);
1501	if (ret)
1502		eap_peer_method_free(eap);
1503	return ret;
1504}
1505
1506
1507#ifdef EAP_AKA_PRIME
1508int eap_peer_aka_prime_register(void)
1509{
1510	struct eap_method *eap;
1511	int ret;
1512
1513	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1514				    EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1515				    "AKA'");
1516	if (eap == NULL)
1517		return -1;
1518
1519	eap->init = eap_aka_prime_init;
1520	eap->deinit = eap_aka_deinit;
1521	eap->process = eap_aka_process;
1522	eap->isKeyAvailable = eap_aka_isKeyAvailable;
1523	eap->getKey = eap_aka_getKey;
1524	eap->getSessionId = eap_aka_get_session_id;
1525	eap->has_reauth_data = eap_aka_has_reauth_data;
1526	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1527	eap->init_for_reauth = eap_aka_init_for_reauth;
1528	eap->get_identity = eap_aka_get_identity;
1529	eap->get_emsk = eap_aka_get_emsk;
1530
1531	ret = eap_peer_method_register(eap);
1532	if (ret)
1533		eap_peer_method_free(eap);
1534
1535	return ret;
1536}
1537#endif /* EAP_AKA_PRIME */
1538