1/*
2 * hostapd / EAP-SIM (RFC 4186)
3 * Copyright (c) 2005-2008, Jouni Malinen <j@w1.fi>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15#include "includes.h"
16
17#include "common.h"
18#include "eap_server/eap_i.h"
19#include "eap_common/eap_sim_common.h"
20#include "eap_server/eap_sim_db.h"
21
22
23struct eap_sim_data {
24	u8 mk[EAP_SIM_MK_LEN];
25	u8 nonce_mt[EAP_SIM_NONCE_MT_LEN];
26	u8 nonce_s[EAP_SIM_NONCE_S_LEN];
27	u8 k_aut[EAP_SIM_K_AUT_LEN];
28	u8 k_encr[EAP_SIM_K_ENCR_LEN];
29	u8 msk[EAP_SIM_KEYING_DATA_LEN];
30	u8 emsk[EAP_EMSK_LEN];
31	u8 kc[EAP_SIM_MAX_CHAL][EAP_SIM_KC_LEN];
32	u8 sres[EAP_SIM_MAX_CHAL][EAP_SIM_SRES_LEN];
33	u8 rand[EAP_SIM_MAX_CHAL][GSM_RAND_LEN];
34	int num_chal;
35	enum {
36		START, CHALLENGE, REAUTH, NOTIFICATION, SUCCESS, FAILURE
37	} state;
38	char *next_pseudonym;
39	char *next_reauth_id;
40	u16 counter;
41	struct eap_sim_reauth *reauth;
42	u16 notification;
43	int use_result_ind;
44};
45
46
47static const char * eap_sim_state_txt(int state)
48{
49	switch (state) {
50	case START:
51		return "START";
52	case CHALLENGE:
53		return "CHALLENGE";
54	case REAUTH:
55		return "REAUTH";
56	case SUCCESS:
57		return "SUCCESS";
58	case FAILURE:
59		return "FAILURE";
60	case NOTIFICATION:
61		return "NOTIFICATION";
62	default:
63		return "Unknown?!";
64	}
65}
66
67
68static void eap_sim_state(struct eap_sim_data *data, int state)
69{
70	wpa_printf(MSG_DEBUG, "EAP-SIM: %s -> %s",
71		   eap_sim_state_txt(data->state),
72		   eap_sim_state_txt(state));
73	data->state = state;
74}
75
76
77static void * eap_sim_init(struct eap_sm *sm)
78{
79	struct eap_sim_data *data;
80
81	if (sm->eap_sim_db_priv == NULL) {
82		wpa_printf(MSG_WARNING, "EAP-SIM: eap_sim_db not configured");
83		return NULL;
84	}
85
86	data = os_zalloc(sizeof(*data));
87	if (data == NULL)
88		return NULL;
89	data->state = START;
90
91	return data;
92}
93
94
95static void eap_sim_reset(struct eap_sm *sm, void *priv)
96{
97	struct eap_sim_data *data = priv;
98	os_free(data->next_pseudonym);
99	os_free(data->next_reauth_id);
100	os_free(data);
101}
102
103
104static struct wpabuf * eap_sim_build_start(struct eap_sm *sm,
105					   struct eap_sim_data *data, u8 id)
106{
107	struct eap_sim_msg *msg;
108	u8 ver[2];
109
110	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Start");
111	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
112			       EAP_SIM_SUBTYPE_START);
113	if (eap_sim_db_identity_known(sm->eap_sim_db_priv, sm->identity,
114				      sm->identity_len)) {
115		wpa_printf(MSG_DEBUG, "   AT_PERMANENT_ID_REQ");
116		eap_sim_msg_add(msg, EAP_SIM_AT_PERMANENT_ID_REQ, 0, NULL, 0);
117	} else {
118		/*
119		 * RFC 4186, Chap. 4.2.4 recommends that identity from EAP is
120		 * ignored and the SIM/Start is used to request the identity.
121		 */
122		wpa_printf(MSG_DEBUG, "   AT_ANY_ID_REQ");
123		eap_sim_msg_add(msg, EAP_SIM_AT_ANY_ID_REQ, 0, NULL, 0);
124	}
125	wpa_printf(MSG_DEBUG, "   AT_VERSION_LIST");
126	ver[0] = 0;
127	ver[1] = EAP_SIM_VERSION;
128	eap_sim_msg_add(msg, EAP_SIM_AT_VERSION_LIST, sizeof(ver),
129			ver, sizeof(ver));
130	return eap_sim_msg_finish(msg, NULL, NULL, 0);
131}
132
133
134static int eap_sim_build_encr(struct eap_sm *sm, struct eap_sim_data *data,
135			      struct eap_sim_msg *msg, u16 counter,
136			      const u8 *nonce_s)
137{
138	os_free(data->next_pseudonym);
139	data->next_pseudonym =
140		eap_sim_db_get_next_pseudonym(sm->eap_sim_db_priv, 0);
141	os_free(data->next_reauth_id);
142	if (data->counter <= EAP_SIM_MAX_FAST_REAUTHS) {
143		data->next_reauth_id =
144			eap_sim_db_get_next_reauth_id(sm->eap_sim_db_priv, 0);
145	} else {
146		wpa_printf(MSG_DEBUG, "EAP-SIM: Max fast re-authentication "
147			   "count exceeded - force full authentication");
148		data->next_reauth_id = NULL;
149	}
150
151	if (data->next_pseudonym == NULL && data->next_reauth_id == NULL &&
152	    counter == 0 && nonce_s == NULL)
153		return 0;
154
155	wpa_printf(MSG_DEBUG, "   AT_IV");
156	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
157	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
158
159	if (counter > 0) {
160		wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)", counter);
161		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
162	}
163
164	if (nonce_s) {
165		wpa_printf(MSG_DEBUG, "   *AT_NONCE_S");
166		eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_S, 0, nonce_s,
167				EAP_SIM_NONCE_S_LEN);
168	}
169
170	if (data->next_pseudonym) {
171		wpa_printf(MSG_DEBUG, "   *AT_NEXT_PSEUDONYM (%s)",
172			   data->next_pseudonym);
173		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_PSEUDONYM,
174				os_strlen(data->next_pseudonym),
175				(u8 *) data->next_pseudonym,
176				os_strlen(data->next_pseudonym));
177	}
178
179	if (data->next_reauth_id) {
180		wpa_printf(MSG_DEBUG, "   *AT_NEXT_REAUTH_ID (%s)",
181			   data->next_reauth_id);
182		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_REAUTH_ID,
183				os_strlen(data->next_reauth_id),
184				(u8 *) data->next_reauth_id,
185				os_strlen(data->next_reauth_id));
186	}
187
188	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
189		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt "
190			   "AT_ENCR_DATA");
191		return -1;
192	}
193
194	return 0;
195}
196
197
198static struct wpabuf * eap_sim_build_challenge(struct eap_sm *sm,
199					       struct eap_sim_data *data,
200					       u8 id)
201{
202	struct eap_sim_msg *msg;
203
204	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Challenge");
205	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
206			       EAP_SIM_SUBTYPE_CHALLENGE);
207	wpa_printf(MSG_DEBUG, "   AT_RAND");
208	eap_sim_msg_add(msg, EAP_SIM_AT_RAND, 0, (u8 *) data->rand,
209			data->num_chal * GSM_RAND_LEN);
210
211	if (eap_sim_build_encr(sm, data, msg, 0, NULL)) {
212		eap_sim_msg_free(msg);
213		return NULL;
214	}
215
216	if (sm->eap_sim_aka_result_ind) {
217		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
218		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
219	}
220
221	wpa_printf(MSG_DEBUG, "   AT_MAC");
222	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
223	return eap_sim_msg_finish(msg, data->k_aut, data->nonce_mt,
224				  EAP_SIM_NONCE_MT_LEN);
225}
226
227
228static struct wpabuf * eap_sim_build_reauth(struct eap_sm *sm,
229					    struct eap_sim_data *data, u8 id)
230{
231	struct eap_sim_msg *msg;
232
233	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Re-authentication");
234
235	if (os_get_random(data->nonce_s, EAP_SIM_NONCE_S_LEN))
236		return NULL;
237	wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: NONCE_S",
238			data->nonce_s, EAP_SIM_NONCE_S_LEN);
239
240	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
241			    data->emsk);
242	eap_sim_derive_keys_reauth(data->counter, sm->identity,
243				   sm->identity_len, data->nonce_s, data->mk,
244				   data->msk, data->emsk);
245
246	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
247			       EAP_SIM_SUBTYPE_REAUTHENTICATION);
248
249	if (eap_sim_build_encr(sm, data, msg, data->counter, data->nonce_s)) {
250		eap_sim_msg_free(msg);
251		return NULL;
252	}
253
254	if (sm->eap_sim_aka_result_ind) {
255		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
256		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
257	}
258
259	wpa_printf(MSG_DEBUG, "   AT_MAC");
260	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
261	return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
262}
263
264
265static struct wpabuf * eap_sim_build_notification(struct eap_sm *sm,
266						  struct eap_sim_data *data,
267						  u8 id)
268{
269	struct eap_sim_msg *msg;
270
271	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Notification");
272	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
273			       EAP_SIM_SUBTYPE_NOTIFICATION);
274	wpa_printf(MSG_DEBUG, "   AT_NOTIFICATION (%d)", data->notification);
275	eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, data->notification,
276			NULL, 0);
277	if (data->use_result_ind) {
278		if (data->reauth) {
279			wpa_printf(MSG_DEBUG, "   AT_IV");
280			wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
281			eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
282						   EAP_SIM_AT_ENCR_DATA);
283			wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)",
284				   data->counter);
285			eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
286					NULL, 0);
287
288			if (eap_sim_msg_add_encr_end(msg, data->k_encr,
289						     EAP_SIM_AT_PADDING)) {
290				wpa_printf(MSG_WARNING, "EAP-SIM: Failed to "
291					   "encrypt AT_ENCR_DATA");
292				eap_sim_msg_free(msg);
293				return NULL;
294			}
295		}
296
297		wpa_printf(MSG_DEBUG, "   AT_MAC");
298		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
299	}
300	return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
301}
302
303
304static struct wpabuf * eap_sim_buildReq(struct eap_sm *sm, void *priv, u8 id)
305{
306	struct eap_sim_data *data = priv;
307
308	switch (data->state) {
309	case START:
310		return eap_sim_build_start(sm, data, id);
311	case CHALLENGE:
312		return eap_sim_build_challenge(sm, data, id);
313	case REAUTH:
314		return eap_sim_build_reauth(sm, data, id);
315	case NOTIFICATION:
316		return eap_sim_build_notification(sm, data, id);
317	default:
318		wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
319			   "buildReq", data->state);
320		break;
321	}
322	return NULL;
323}
324
325
326static Boolean eap_sim_check(struct eap_sm *sm, void *priv,
327			     struct wpabuf *respData)
328{
329	struct eap_sim_data *data = priv;
330	const u8 *pos;
331	size_t len;
332	u8 subtype;
333
334	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, respData, &len);
335	if (pos == NULL || len < 3) {
336		wpa_printf(MSG_INFO, "EAP-SIM: Invalid frame");
337		return TRUE;
338	}
339	subtype = *pos;
340
341	if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR)
342		return FALSE;
343
344	switch (data->state) {
345	case START:
346		if (subtype != EAP_SIM_SUBTYPE_START) {
347			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
348				   "subtype %d", subtype);
349			return TRUE;
350		}
351		break;
352	case CHALLENGE:
353		if (subtype != EAP_SIM_SUBTYPE_CHALLENGE) {
354			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
355				   "subtype %d", subtype);
356			return TRUE;
357		}
358		break;
359	case REAUTH:
360		if (subtype != EAP_SIM_SUBTYPE_REAUTHENTICATION) {
361			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
362				   "subtype %d", subtype);
363			return TRUE;
364		}
365		break;
366	case NOTIFICATION:
367		if (subtype != EAP_SIM_SUBTYPE_NOTIFICATION) {
368			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
369				   "subtype %d", subtype);
370			return TRUE;
371		}
372		break;
373	default:
374		wpa_printf(MSG_INFO, "EAP-SIM: Unexpected state (%d) for "
375			   "processing a response", data->state);
376		return TRUE;
377	}
378
379	return FALSE;
380}
381
382
383static int eap_sim_supported_ver(struct eap_sim_data *data, int version)
384{
385	return version == EAP_SIM_VERSION;
386}
387
388
389static void eap_sim_process_start(struct eap_sm *sm,
390				  struct eap_sim_data *data,
391				  struct wpabuf *respData,
392				  struct eap_sim_attrs *attr)
393{
394	const u8 *identity;
395	size_t identity_len;
396	u8 ver_list[2];
397
398	wpa_printf(MSG_DEBUG, "EAP-SIM: Receive start response");
399
400	if (attr->identity) {
401		os_free(sm->identity);
402		sm->identity = os_malloc(attr->identity_len);
403		if (sm->identity) {
404			os_memcpy(sm->identity, attr->identity,
405				  attr->identity_len);
406			sm->identity_len = attr->identity_len;
407		}
408	}
409
410	identity = NULL;
411	identity_len = 0;
412
413	if (sm->identity && sm->identity_len > 0 &&
414	    sm->identity[0] == EAP_SIM_PERMANENT_PREFIX) {
415		identity = sm->identity;
416		identity_len = sm->identity_len;
417	} else {
418		identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv,
419						    sm->identity,
420						    sm->identity_len,
421						    &identity_len);
422		if (identity == NULL) {
423			data->reauth = eap_sim_db_get_reauth_entry(
424				sm->eap_sim_db_priv, sm->identity,
425				sm->identity_len);
426			if (data->reauth) {
427				wpa_printf(MSG_DEBUG, "EAP-SIM: Using fast "
428					   "re-authentication");
429				identity = data->reauth->identity;
430				identity_len = data->reauth->identity_len;
431				data->counter = data->reauth->counter;
432				os_memcpy(data->mk, data->reauth->mk,
433					  EAP_SIM_MK_LEN);
434			}
435		}
436	}
437
438	if (identity == NULL) {
439		wpa_printf(MSG_DEBUG, "EAP-SIM: Could not get proper permanent"
440			   " user name");
441		eap_sim_state(data, FAILURE);
442		return;
443	}
444
445	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity",
446			  identity, identity_len);
447
448	if (data->reauth) {
449		eap_sim_state(data, REAUTH);
450		return;
451	}
452
453	if (attr->nonce_mt == NULL || attr->selected_version < 0) {
454		wpa_printf(MSG_DEBUG, "EAP-SIM: Start/Response missing "
455			   "required attributes");
456		eap_sim_state(data, FAILURE);
457		return;
458	}
459
460	if (!eap_sim_supported_ver(data, attr->selected_version)) {
461		wpa_printf(MSG_DEBUG, "EAP-SIM: Peer selected unsupported "
462			   "version %d", attr->selected_version);
463		eap_sim_state(data, FAILURE);
464		return;
465	}
466
467	data->counter = 0; /* reset re-auth counter since this is full auth */
468	data->reauth = NULL;
469
470	data->num_chal = eap_sim_db_get_gsm_triplets(
471		sm->eap_sim_db_priv, identity, identity_len,
472		EAP_SIM_MAX_CHAL,
473		(u8 *) data->rand, (u8 *) data->kc, (u8 *) data->sres, sm);
474	if (data->num_chal == EAP_SIM_DB_PENDING) {
475		wpa_printf(MSG_DEBUG, "EAP-SIM: GSM authentication triplets "
476			   "not yet available - pending request");
477		sm->method_pending = METHOD_PENDING_WAIT;
478		return;
479	}
480	if (data->num_chal < 2) {
481		wpa_printf(MSG_INFO, "EAP-SIM: Failed to get GSM "
482			   "authentication triplets for the peer");
483		eap_sim_state(data, FAILURE);
484		return;
485	}
486
487	identity_len = sm->identity_len;
488	while (identity_len > 0 && sm->identity[identity_len - 1] == '\0') {
489		wpa_printf(MSG_DEBUG, "EAP-SIM: Workaround - drop last null "
490			   "character from identity");
491		identity_len--;
492	}
493	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity for MK derivation",
494			  sm->identity, identity_len);
495
496	os_memcpy(data->nonce_mt, attr->nonce_mt, EAP_SIM_NONCE_MT_LEN);
497	WPA_PUT_BE16(ver_list, EAP_SIM_VERSION);
498	eap_sim_derive_mk(sm->identity, identity_len, attr->nonce_mt,
499			  attr->selected_version, ver_list, sizeof(ver_list),
500			  data->num_chal, (const u8 *) data->kc, data->mk);
501	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
502			    data->emsk);
503
504	eap_sim_state(data, CHALLENGE);
505}
506
507
508static void eap_sim_process_challenge(struct eap_sm *sm,
509				      struct eap_sim_data *data,
510				      struct wpabuf *respData,
511				      struct eap_sim_attrs *attr)
512{
513	const u8 *identity;
514	size_t identity_len;
515
516	if (attr->mac == NULL ||
517	    eap_sim_verify_mac(data->k_aut, respData, attr->mac,
518			       (u8 *) data->sres,
519			       data->num_chal * EAP_SIM_SRES_LEN)) {
520		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
521			   "did not include valid AT_MAC");
522		eap_sim_state(data, FAILURE);
523		return;
524	}
525
526	wpa_printf(MSG_DEBUG, "EAP-SIM: Challenge response includes the "
527		   "correct AT_MAC");
528	if (sm->eap_sim_aka_result_ind && attr->result_ind) {
529		data->use_result_ind = 1;
530		data->notification = EAP_SIM_SUCCESS;
531		eap_sim_state(data, NOTIFICATION);
532	} else
533		eap_sim_state(data, SUCCESS);
534
535	identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv, sm->identity,
536					    sm->identity_len, &identity_len);
537	if (identity == NULL) {
538		identity = sm->identity;
539		identity_len = sm->identity_len;
540	}
541
542	if (data->next_pseudonym) {
543		eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
544					 identity_len,
545					 data->next_pseudonym);
546		data->next_pseudonym = NULL;
547	}
548	if (data->next_reauth_id) {
549		eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
550				      identity_len,
551				      data->next_reauth_id, data->counter + 1,
552				      data->mk);
553		data->next_reauth_id = NULL;
554	}
555}
556
557
558static void eap_sim_process_reauth(struct eap_sm *sm,
559				   struct eap_sim_data *data,
560				   struct wpabuf *respData,
561				   struct eap_sim_attrs *attr)
562{
563	struct eap_sim_attrs eattr;
564	u8 *decrypted = NULL;
565	const u8 *identity, *id2;
566	size_t identity_len, id2_len;
567
568	if (attr->mac == NULL ||
569	    eap_sim_verify_mac(data->k_aut, respData, attr->mac, data->nonce_s,
570			       EAP_SIM_NONCE_S_LEN)) {
571		wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
572			   "did not include valid AT_MAC");
573		goto fail;
574	}
575
576	if (attr->encr_data == NULL || attr->iv == NULL) {
577		wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication "
578			   "message did not include encrypted data");
579		goto fail;
580	}
581
582	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
583				       attr->encr_data_len, attr->iv, &eattr,
584				       0);
585	if (decrypted == NULL) {
586		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted "
587			   "data from reauthentication message");
588		goto fail;
589	}
590
591	if (eattr.counter != data->counter) {
592		wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
593			   "used incorrect counter %u, expected %u",
594			   eattr.counter, data->counter);
595		goto fail;
596	}
597	os_free(decrypted);
598	decrypted = NULL;
599
600	wpa_printf(MSG_DEBUG, "EAP-SIM: Re-authentication response includes "
601		   "the correct AT_MAC");
602	if (sm->eap_sim_aka_result_ind && attr->result_ind) {
603		data->use_result_ind = 1;
604		data->notification = EAP_SIM_SUCCESS;
605		eap_sim_state(data, NOTIFICATION);
606	} else
607		eap_sim_state(data, SUCCESS);
608
609	if (data->reauth) {
610		identity = data->reauth->identity;
611		identity_len = data->reauth->identity_len;
612	} else {
613		identity = sm->identity;
614		identity_len = sm->identity_len;
615	}
616
617	id2 = eap_sim_db_get_permanent(sm->eap_sim_db_priv, identity,
618				       identity_len, &id2_len);
619	if (id2) {
620		identity = id2;
621		identity_len = id2_len;
622	}
623
624	if (data->next_pseudonym) {
625		eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
626					 identity_len, data->next_pseudonym);
627		data->next_pseudonym = NULL;
628	}
629	if (data->next_reauth_id) {
630		eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
631				      identity_len, data->next_reauth_id,
632				      data->counter + 1, data->mk);
633		data->next_reauth_id = NULL;
634	} else {
635		eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
636		data->reauth = NULL;
637	}
638
639	return;
640
641fail:
642	eap_sim_state(data, FAILURE);
643	eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
644	data->reauth = NULL;
645	os_free(decrypted);
646}
647
648
649static void eap_sim_process_client_error(struct eap_sm *sm,
650					 struct eap_sim_data *data,
651					 struct wpabuf *respData,
652					 struct eap_sim_attrs *attr)
653{
654	wpa_printf(MSG_DEBUG, "EAP-SIM: Client reported error %d",
655		   attr->client_error_code);
656	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
657		eap_sim_state(data, SUCCESS);
658	else
659		eap_sim_state(data, FAILURE);
660}
661
662
663static void eap_sim_process_notification(struct eap_sm *sm,
664					 struct eap_sim_data *data,
665					 struct wpabuf *respData,
666					 struct eap_sim_attrs *attr)
667{
668	wpa_printf(MSG_DEBUG, "EAP-SIM: Client replied to notification");
669	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
670		eap_sim_state(data, SUCCESS);
671	else
672		eap_sim_state(data, FAILURE);
673}
674
675
676static void eap_sim_process(struct eap_sm *sm, void *priv,
677			    struct wpabuf *respData)
678{
679	struct eap_sim_data *data = priv;
680	const u8 *pos, *end;
681	u8 subtype;
682	size_t len;
683	struct eap_sim_attrs attr;
684
685	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, respData, &len);
686	if (pos == NULL || len < 3)
687		return;
688
689	end = pos + len;
690	subtype = *pos;
691	pos += 3;
692
693	if (eap_sim_parse_attr(pos, end, &attr, 0, 0)) {
694		wpa_printf(MSG_DEBUG, "EAP-SIM: Failed to parse attributes");
695		eap_sim_state(data, FAILURE);
696		return;
697	}
698
699	if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR) {
700		eap_sim_process_client_error(sm, data, respData, &attr);
701		return;
702	}
703
704	switch (data->state) {
705	case START:
706		eap_sim_process_start(sm, data, respData, &attr);
707		break;
708	case CHALLENGE:
709		eap_sim_process_challenge(sm, data, respData, &attr);
710		break;
711	case REAUTH:
712		eap_sim_process_reauth(sm, data, respData, &attr);
713		break;
714	case NOTIFICATION:
715		eap_sim_process_notification(sm, data, respData, &attr);
716		break;
717	default:
718		wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
719			   "process", data->state);
720		break;
721	}
722}
723
724
725static Boolean eap_sim_isDone(struct eap_sm *sm, void *priv)
726{
727	struct eap_sim_data *data = priv;
728	return data->state == SUCCESS || data->state == FAILURE;
729}
730
731
732static u8 * eap_sim_getKey(struct eap_sm *sm, void *priv, size_t *len)
733{
734	struct eap_sim_data *data = priv;
735	u8 *key;
736
737	if (data->state != SUCCESS)
738		return NULL;
739
740	key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
741	if (key == NULL)
742		return NULL;
743	os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
744	*len = EAP_SIM_KEYING_DATA_LEN;
745	return key;
746}
747
748
749static u8 * eap_sim_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
750{
751	struct eap_sim_data *data = priv;
752	u8 *key;
753
754	if (data->state != SUCCESS)
755		return NULL;
756
757	key = os_malloc(EAP_EMSK_LEN);
758	if (key == NULL)
759		return NULL;
760	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
761	*len = EAP_EMSK_LEN;
762	return key;
763}
764
765
766static Boolean eap_sim_isSuccess(struct eap_sm *sm, void *priv)
767{
768	struct eap_sim_data *data = priv;
769	return data->state == SUCCESS;
770}
771
772
773int eap_server_sim_register(void)
774{
775	struct eap_method *eap;
776	int ret;
777
778	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
779				      EAP_VENDOR_IETF, EAP_TYPE_SIM, "SIM");
780	if (eap == NULL)
781		return -1;
782
783	eap->init = eap_sim_init;
784	eap->reset = eap_sim_reset;
785	eap->buildReq = eap_sim_buildReq;
786	eap->check = eap_sim_check;
787	eap->process = eap_sim_process;
788	eap->isDone = eap_sim_isDone;
789	eap->getKey = eap_sim_getKey;
790	eap->isSuccess = eap_sim_isSuccess;
791	eap->get_emsk = eap_sim_get_emsk;
792
793	ret = eap_server_method_register(eap);
794	if (ret)
795		eap_server_method_free(eap);
796	return ret;
797}
798