eap_server_sim.c revision 04949598a23f501be6eec21697465fd46a28840a
1/*
2 * hostapd / EAP-SIM (RFC 4186)
3 * Copyright (c) 2005-2008, 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 "crypto/random.h"
13#include "eap_server/eap_i.h"
14#include "eap_common/eap_sim_common.h"
15#include "eap_server/eap_sim_db.h"
16
17
18struct eap_sim_data {
19	u8 mk[EAP_SIM_MK_LEN];
20	u8 nonce_mt[EAP_SIM_NONCE_MT_LEN];
21	u8 nonce_s[EAP_SIM_NONCE_S_LEN];
22	u8 k_aut[EAP_SIM_K_AUT_LEN];
23	u8 k_encr[EAP_SIM_K_ENCR_LEN];
24	u8 msk[EAP_SIM_KEYING_DATA_LEN];
25	u8 emsk[EAP_EMSK_LEN];
26	u8 kc[EAP_SIM_MAX_CHAL][EAP_SIM_KC_LEN];
27	u8 sres[EAP_SIM_MAX_CHAL][EAP_SIM_SRES_LEN];
28	u8 rand[EAP_SIM_MAX_CHAL][GSM_RAND_LEN];
29	int num_chal;
30	enum {
31		START, CHALLENGE, REAUTH, NOTIFICATION, SUCCESS, FAILURE
32	} state;
33	char *next_pseudonym;
34	char *next_reauth_id;
35	u16 counter;
36	struct eap_sim_reauth *reauth;
37	u16 notification;
38	int use_result_ind;
39};
40
41
42static const char * eap_sim_state_txt(int state)
43{
44	switch (state) {
45	case START:
46		return "START";
47	case CHALLENGE:
48		return "CHALLENGE";
49	case REAUTH:
50		return "REAUTH";
51	case SUCCESS:
52		return "SUCCESS";
53	case FAILURE:
54		return "FAILURE";
55	case NOTIFICATION:
56		return "NOTIFICATION";
57	default:
58		return "Unknown?!";
59	}
60}
61
62
63static void eap_sim_state(struct eap_sim_data *data, int state)
64{
65	wpa_printf(MSG_DEBUG, "EAP-SIM: %s -> %s",
66		   eap_sim_state_txt(data->state),
67		   eap_sim_state_txt(state));
68	data->state = state;
69}
70
71
72static void * eap_sim_init(struct eap_sm *sm)
73{
74	struct eap_sim_data *data;
75
76	if (sm->eap_sim_db_priv == NULL) {
77		wpa_printf(MSG_WARNING, "EAP-SIM: eap_sim_db not configured");
78		return NULL;
79	}
80
81	data = os_zalloc(sizeof(*data));
82	if (data == NULL)
83		return NULL;
84	data->state = START;
85
86	return data;
87}
88
89
90static void eap_sim_reset(struct eap_sm *sm, void *priv)
91{
92	struct eap_sim_data *data = priv;
93	os_free(data->next_pseudonym);
94	os_free(data->next_reauth_id);
95	os_free(data);
96}
97
98
99static struct wpabuf * eap_sim_build_start(struct eap_sm *sm,
100					   struct eap_sim_data *data, u8 id)
101{
102	struct eap_sim_msg *msg;
103	u8 ver[2];
104
105	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Start");
106	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
107			       EAP_SIM_SUBTYPE_START);
108	if (eap_sim_db_identity_known(sm->eap_sim_db_priv, sm->identity,
109				      sm->identity_len)) {
110		if (sm->identity_len > 0 &&
111		    sm->identity[0] == EAP_SIM_REAUTH_ID_PREFIX) {
112			/* Reauth id may have expired - try fullauth */
113			wpa_printf(MSG_DEBUG, "   AT_FULLAUTH_ID_REQ");
114			eap_sim_msg_add(msg, EAP_SIM_AT_FULLAUTH_ID_REQ, 0,
115					NULL, 0);
116		} else {
117			wpa_printf(MSG_DEBUG, "   AT_PERMANENT_ID_REQ");
118			eap_sim_msg_add(msg, EAP_SIM_AT_PERMANENT_ID_REQ, 0,
119					NULL, 0);
120		}
121	} else {
122		/*
123		 * RFC 4186, Chap. 4.2.4 recommends that identity from EAP is
124		 * ignored and the SIM/Start is used to request the identity.
125		 */
126		wpa_printf(MSG_DEBUG, "   AT_ANY_ID_REQ");
127		eap_sim_msg_add(msg, EAP_SIM_AT_ANY_ID_REQ, 0, NULL, 0);
128	}
129	wpa_printf(MSG_DEBUG, "   AT_VERSION_LIST");
130	ver[0] = 0;
131	ver[1] = EAP_SIM_VERSION;
132	eap_sim_msg_add(msg, EAP_SIM_AT_VERSION_LIST, sizeof(ver),
133			ver, sizeof(ver));
134	return eap_sim_msg_finish(msg, NULL, NULL, 0);
135}
136
137
138static int eap_sim_build_encr(struct eap_sm *sm, struct eap_sim_data *data,
139			      struct eap_sim_msg *msg, u16 counter,
140			      const u8 *nonce_s)
141{
142	os_free(data->next_pseudonym);
143	if (nonce_s == NULL) {
144		data->next_pseudonym =
145			eap_sim_db_get_next_pseudonym(sm->eap_sim_db_priv,
146						      EAP_SIM_DB_SIM);
147	} else {
148		/* Do not update pseudonym during re-authentication */
149		data->next_pseudonym = NULL;
150	}
151	os_free(data->next_reauth_id);
152	if (data->counter <= EAP_SIM_MAX_FAST_REAUTHS) {
153		data->next_reauth_id =
154			eap_sim_db_get_next_reauth_id(sm->eap_sim_db_priv,
155						      EAP_SIM_DB_SIM);
156	} else {
157		wpa_printf(MSG_DEBUG, "EAP-SIM: Max fast re-authentication "
158			   "count exceeded - force full authentication");
159		data->next_reauth_id = NULL;
160	}
161
162	if (data->next_pseudonym == NULL && data->next_reauth_id == NULL &&
163	    counter == 0 && nonce_s == NULL)
164		return 0;
165
166	wpa_printf(MSG_DEBUG, "   AT_IV");
167	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
168	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
169
170	if (counter > 0) {
171		wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)", counter);
172		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
173	}
174
175	if (nonce_s) {
176		wpa_printf(MSG_DEBUG, "   *AT_NONCE_S");
177		eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_S, 0, nonce_s,
178				EAP_SIM_NONCE_S_LEN);
179	}
180
181	if (data->next_pseudonym) {
182		wpa_printf(MSG_DEBUG, "   *AT_NEXT_PSEUDONYM (%s)",
183			   data->next_pseudonym);
184		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_PSEUDONYM,
185				os_strlen(data->next_pseudonym),
186				(u8 *) data->next_pseudonym,
187				os_strlen(data->next_pseudonym));
188	}
189
190	if (data->next_reauth_id) {
191		wpa_printf(MSG_DEBUG, "   *AT_NEXT_REAUTH_ID (%s)",
192			   data->next_reauth_id);
193		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_REAUTH_ID,
194				os_strlen(data->next_reauth_id),
195				(u8 *) data->next_reauth_id,
196				os_strlen(data->next_reauth_id));
197	}
198
199	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
200		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt "
201			   "AT_ENCR_DATA");
202		return -1;
203	}
204
205	return 0;
206}
207
208
209static struct wpabuf * eap_sim_build_challenge(struct eap_sm *sm,
210					       struct eap_sim_data *data,
211					       u8 id)
212{
213	struct eap_sim_msg *msg;
214
215	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Challenge");
216	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
217			       EAP_SIM_SUBTYPE_CHALLENGE);
218	wpa_printf(MSG_DEBUG, "   AT_RAND");
219	eap_sim_msg_add(msg, EAP_SIM_AT_RAND, 0, (u8 *) data->rand,
220			data->num_chal * GSM_RAND_LEN);
221
222	if (eap_sim_build_encr(sm, data, msg, 0, NULL)) {
223		eap_sim_msg_free(msg);
224		return NULL;
225	}
226
227	if (sm->eap_sim_aka_result_ind) {
228		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
229		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
230	}
231
232	wpa_printf(MSG_DEBUG, "   AT_MAC");
233	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
234	return eap_sim_msg_finish(msg, data->k_aut, data->nonce_mt,
235				  EAP_SIM_NONCE_MT_LEN);
236}
237
238
239static struct wpabuf * eap_sim_build_reauth(struct eap_sm *sm,
240					    struct eap_sim_data *data, u8 id)
241{
242	struct eap_sim_msg *msg;
243
244	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Re-authentication");
245
246	if (random_get_bytes(data->nonce_s, EAP_SIM_NONCE_S_LEN))
247		return NULL;
248	wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: NONCE_S",
249			data->nonce_s, EAP_SIM_NONCE_S_LEN);
250
251	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
252			    data->emsk);
253	eap_sim_derive_keys_reauth(data->counter, sm->identity,
254				   sm->identity_len, data->nonce_s, data->mk,
255				   data->msk, data->emsk);
256
257	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
258			       EAP_SIM_SUBTYPE_REAUTHENTICATION);
259
260	if (eap_sim_build_encr(sm, data, msg, data->counter, data->nonce_s)) {
261		eap_sim_msg_free(msg);
262		return NULL;
263	}
264
265	if (sm->eap_sim_aka_result_ind) {
266		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
267		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
268	}
269
270	wpa_printf(MSG_DEBUG, "   AT_MAC");
271	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
272	return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
273}
274
275
276static struct wpabuf * eap_sim_build_notification(struct eap_sm *sm,
277						  struct eap_sim_data *data,
278						  u8 id)
279{
280	struct eap_sim_msg *msg;
281
282	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Notification");
283	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
284			       EAP_SIM_SUBTYPE_NOTIFICATION);
285	wpa_printf(MSG_DEBUG, "   AT_NOTIFICATION (%d)", data->notification);
286	eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, data->notification,
287			NULL, 0);
288	if (data->use_result_ind) {
289		if (data->reauth) {
290			wpa_printf(MSG_DEBUG, "   AT_IV");
291			wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
292			eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
293						   EAP_SIM_AT_ENCR_DATA);
294			wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)",
295				   data->counter);
296			eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
297					NULL, 0);
298
299			if (eap_sim_msg_add_encr_end(msg, data->k_encr,
300						     EAP_SIM_AT_PADDING)) {
301				wpa_printf(MSG_WARNING, "EAP-SIM: Failed to "
302					   "encrypt AT_ENCR_DATA");
303				eap_sim_msg_free(msg);
304				return NULL;
305			}
306		}
307
308		wpa_printf(MSG_DEBUG, "   AT_MAC");
309		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
310	}
311	return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
312}
313
314
315static struct wpabuf * eap_sim_buildReq(struct eap_sm *sm, void *priv, u8 id)
316{
317	struct eap_sim_data *data = priv;
318
319	switch (data->state) {
320	case START:
321		return eap_sim_build_start(sm, data, id);
322	case CHALLENGE:
323		return eap_sim_build_challenge(sm, data, id);
324	case REAUTH:
325		return eap_sim_build_reauth(sm, data, id);
326	case NOTIFICATION:
327		return eap_sim_build_notification(sm, data, id);
328	default:
329		wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
330			   "buildReq", data->state);
331		break;
332	}
333	return NULL;
334}
335
336
337static Boolean eap_sim_check(struct eap_sm *sm, void *priv,
338			     struct wpabuf *respData)
339{
340	struct eap_sim_data *data = priv;
341	const u8 *pos;
342	size_t len;
343	u8 subtype;
344
345	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, respData, &len);
346	if (pos == NULL || len < 3) {
347		wpa_printf(MSG_INFO, "EAP-SIM: Invalid frame");
348		return TRUE;
349	}
350	subtype = *pos;
351
352	if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR)
353		return FALSE;
354
355	switch (data->state) {
356	case START:
357		if (subtype != EAP_SIM_SUBTYPE_START) {
358			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
359				   "subtype %d", subtype);
360			return TRUE;
361		}
362		break;
363	case CHALLENGE:
364		if (subtype != EAP_SIM_SUBTYPE_CHALLENGE) {
365			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
366				   "subtype %d", subtype);
367			return TRUE;
368		}
369		break;
370	case REAUTH:
371		if (subtype != EAP_SIM_SUBTYPE_REAUTHENTICATION) {
372			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
373				   "subtype %d", subtype);
374			return TRUE;
375		}
376		break;
377	case NOTIFICATION:
378		if (subtype != EAP_SIM_SUBTYPE_NOTIFICATION) {
379			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
380				   "subtype %d", subtype);
381			return TRUE;
382		}
383		break;
384	default:
385		wpa_printf(MSG_INFO, "EAP-SIM: Unexpected state (%d) for "
386			   "processing a response", data->state);
387		return TRUE;
388	}
389
390	return FALSE;
391}
392
393
394static int eap_sim_supported_ver(struct eap_sim_data *data, int version)
395{
396	return version == EAP_SIM_VERSION;
397}
398
399
400static void eap_sim_process_start(struct eap_sm *sm,
401				  struct eap_sim_data *data,
402				  struct wpabuf *respData,
403				  struct eap_sim_attrs *attr)
404{
405	const u8 *identity;
406	size_t identity_len;
407	u8 ver_list[2];
408
409	wpa_printf(MSG_DEBUG, "EAP-SIM: Receive start response");
410
411	if (attr->identity) {
412		os_free(sm->identity);
413		sm->identity = os_malloc(attr->identity_len);
414		if (sm->identity) {
415			os_memcpy(sm->identity, attr->identity,
416				  attr->identity_len);
417			sm->identity_len = attr->identity_len;
418		}
419	}
420
421	identity = NULL;
422	identity_len = 0;
423
424	if (sm->identity && sm->identity_len > 0 &&
425	    sm->identity[0] == EAP_SIM_PERMANENT_PREFIX) {
426		identity = sm->identity;
427		identity_len = sm->identity_len;
428	} else {
429		identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv,
430						    sm->identity,
431						    sm->identity_len,
432						    &identity_len);
433		if (identity == NULL) {
434			data->reauth = eap_sim_db_get_reauth_entry(
435				sm->eap_sim_db_priv, sm->identity,
436				sm->identity_len);
437			if (data->reauth) {
438				wpa_printf(MSG_DEBUG, "EAP-SIM: Using fast "
439					   "re-authentication");
440				identity = data->reauth->identity;
441				identity_len = data->reauth->identity_len;
442				data->counter = data->reauth->counter;
443				os_memcpy(data->mk, data->reauth->mk,
444					  EAP_SIM_MK_LEN);
445			}
446		}
447	}
448
449	if (identity == NULL) {
450		wpa_printf(MSG_DEBUG, "EAP-SIM: Could not get proper permanent"
451			   " user name");
452		eap_sim_state(data, FAILURE);
453		return;
454	}
455
456	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity",
457			  identity, identity_len);
458
459	if (data->reauth) {
460		eap_sim_state(data, REAUTH);
461		return;
462	}
463
464	if (attr->nonce_mt == NULL || attr->selected_version < 0) {
465		wpa_printf(MSG_DEBUG, "EAP-SIM: Start/Response missing "
466			   "required attributes");
467		eap_sim_state(data, FAILURE);
468		return;
469	}
470
471	if (!eap_sim_supported_ver(data, attr->selected_version)) {
472		wpa_printf(MSG_DEBUG, "EAP-SIM: Peer selected unsupported "
473			   "version %d", attr->selected_version);
474		eap_sim_state(data, FAILURE);
475		return;
476	}
477
478	data->counter = 0; /* reset re-auth counter since this is full auth */
479	data->reauth = NULL;
480
481	data->num_chal = eap_sim_db_get_gsm_triplets(
482		sm->eap_sim_db_priv, identity, identity_len,
483		EAP_SIM_MAX_CHAL,
484		(u8 *) data->rand, (u8 *) data->kc, (u8 *) data->sres, sm);
485	if (data->num_chal == EAP_SIM_DB_PENDING) {
486		wpa_printf(MSG_DEBUG, "EAP-SIM: GSM authentication triplets "
487			   "not yet available - pending request");
488		sm->method_pending = METHOD_PENDING_WAIT;
489		return;
490	}
491	if (data->num_chal < 2) {
492		wpa_printf(MSG_INFO, "EAP-SIM: Failed to get GSM "
493			   "authentication triplets for the peer");
494		eap_sim_state(data, FAILURE);
495		return;
496	}
497
498	identity_len = sm->identity_len;
499	while (identity_len > 0 && sm->identity[identity_len - 1] == '\0') {
500		wpa_printf(MSG_DEBUG, "EAP-SIM: Workaround - drop last null "
501			   "character from identity");
502		identity_len--;
503	}
504	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity for MK derivation",
505			  sm->identity, identity_len);
506
507	os_memcpy(data->nonce_mt, attr->nonce_mt, EAP_SIM_NONCE_MT_LEN);
508	WPA_PUT_BE16(ver_list, EAP_SIM_VERSION);
509	eap_sim_derive_mk(sm->identity, identity_len, attr->nonce_mt,
510			  attr->selected_version, ver_list, sizeof(ver_list),
511			  data->num_chal, (const u8 *) data->kc, data->mk);
512	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
513			    data->emsk);
514
515	eap_sim_state(data, CHALLENGE);
516}
517
518
519static void eap_sim_process_challenge(struct eap_sm *sm,
520				      struct eap_sim_data *data,
521				      struct wpabuf *respData,
522				      struct eap_sim_attrs *attr)
523{
524	const u8 *identity;
525	size_t identity_len;
526
527	if (attr->mac == NULL ||
528	    eap_sim_verify_mac(data->k_aut, respData, attr->mac,
529			       (u8 *) data->sres,
530			       data->num_chal * EAP_SIM_SRES_LEN)) {
531		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
532			   "did not include valid AT_MAC");
533		eap_sim_state(data, FAILURE);
534		return;
535	}
536
537	wpa_printf(MSG_DEBUG, "EAP-SIM: Challenge response includes the "
538		   "correct AT_MAC");
539	if (sm->eap_sim_aka_result_ind && attr->result_ind) {
540		data->use_result_ind = 1;
541		data->notification = EAP_SIM_SUCCESS;
542		eap_sim_state(data, NOTIFICATION);
543	} else
544		eap_sim_state(data, SUCCESS);
545
546	identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv, sm->identity,
547					    sm->identity_len, &identity_len);
548	if (identity == NULL) {
549		identity = sm->identity;
550		identity_len = sm->identity_len;
551	}
552
553	if (data->next_pseudonym) {
554		eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
555					 identity_len,
556					 data->next_pseudonym);
557		data->next_pseudonym = NULL;
558	}
559	if (data->next_reauth_id) {
560		eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
561				      identity_len,
562				      data->next_reauth_id, data->counter + 1,
563				      data->mk);
564		data->next_reauth_id = NULL;
565	}
566}
567
568
569static void eap_sim_process_reauth(struct eap_sm *sm,
570				   struct eap_sim_data *data,
571				   struct wpabuf *respData,
572				   struct eap_sim_attrs *attr)
573{
574	struct eap_sim_attrs eattr;
575	u8 *decrypted = NULL;
576	const u8 *identity, *id2;
577	size_t identity_len, id2_len;
578
579	if (attr->mac == NULL ||
580	    eap_sim_verify_mac(data->k_aut, respData, attr->mac, data->nonce_s,
581			       EAP_SIM_NONCE_S_LEN)) {
582		wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
583			   "did not include valid AT_MAC");
584		goto fail;
585	}
586
587	if (attr->encr_data == NULL || attr->iv == NULL) {
588		wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication "
589			   "message did not include encrypted data");
590		goto fail;
591	}
592
593	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
594				       attr->encr_data_len, attr->iv, &eattr,
595				       0);
596	if (decrypted == NULL) {
597		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted "
598			   "data from reauthentication message");
599		goto fail;
600	}
601
602	if (eattr.counter != data->counter) {
603		wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
604			   "used incorrect counter %u, expected %u",
605			   eattr.counter, data->counter);
606		goto fail;
607	}
608	os_free(decrypted);
609	decrypted = NULL;
610
611	wpa_printf(MSG_DEBUG, "EAP-SIM: Re-authentication response includes "
612		   "the correct AT_MAC");
613	if (sm->eap_sim_aka_result_ind && attr->result_ind) {
614		data->use_result_ind = 1;
615		data->notification = EAP_SIM_SUCCESS;
616		eap_sim_state(data, NOTIFICATION);
617	} else
618		eap_sim_state(data, SUCCESS);
619
620	if (data->reauth) {
621		identity = data->reauth->identity;
622		identity_len = data->reauth->identity_len;
623	} else {
624		identity = sm->identity;
625		identity_len = sm->identity_len;
626	}
627
628	id2 = eap_sim_db_get_permanent(sm->eap_sim_db_priv, identity,
629				       identity_len, &id2_len);
630	if (id2) {
631		identity = id2;
632		identity_len = id2_len;
633	}
634
635	if (data->next_reauth_id) {
636		eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
637				      identity_len, data->next_reauth_id,
638				      data->counter + 1, data->mk);
639		data->next_reauth_id = NULL;
640	} else {
641		eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
642		data->reauth = NULL;
643	}
644
645	return;
646
647fail:
648	eap_sim_state(data, FAILURE);
649	eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
650	data->reauth = NULL;
651	os_free(decrypted);
652}
653
654
655static void eap_sim_process_client_error(struct eap_sm *sm,
656					 struct eap_sim_data *data,
657					 struct wpabuf *respData,
658					 struct eap_sim_attrs *attr)
659{
660	wpa_printf(MSG_DEBUG, "EAP-SIM: Client reported error %d",
661		   attr->client_error_code);
662	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
663		eap_sim_state(data, SUCCESS);
664	else
665		eap_sim_state(data, FAILURE);
666}
667
668
669static void eap_sim_process_notification(struct eap_sm *sm,
670					 struct eap_sim_data *data,
671					 struct wpabuf *respData,
672					 struct eap_sim_attrs *attr)
673{
674	wpa_printf(MSG_DEBUG, "EAP-SIM: Client replied to notification");
675	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
676		eap_sim_state(data, SUCCESS);
677	else
678		eap_sim_state(data, FAILURE);
679}
680
681
682static void eap_sim_process(struct eap_sm *sm, void *priv,
683			    struct wpabuf *respData)
684{
685	struct eap_sim_data *data = priv;
686	const u8 *pos, *end;
687	u8 subtype;
688	size_t len;
689	struct eap_sim_attrs attr;
690
691	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, respData, &len);
692	if (pos == NULL || len < 3)
693		return;
694
695	end = pos + len;
696	subtype = *pos;
697	pos += 3;
698
699	if (eap_sim_parse_attr(pos, end, &attr, 0, 0)) {
700		wpa_printf(MSG_DEBUG, "EAP-SIM: Failed to parse attributes");
701		eap_sim_state(data, FAILURE);
702		return;
703	}
704
705	if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR) {
706		eap_sim_process_client_error(sm, data, respData, &attr);
707		return;
708	}
709
710	switch (data->state) {
711	case START:
712		eap_sim_process_start(sm, data, respData, &attr);
713		break;
714	case CHALLENGE:
715		eap_sim_process_challenge(sm, data, respData, &attr);
716		break;
717	case REAUTH:
718		eap_sim_process_reauth(sm, data, respData, &attr);
719		break;
720	case NOTIFICATION:
721		eap_sim_process_notification(sm, data, respData, &attr);
722		break;
723	default:
724		wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
725			   "process", data->state);
726		break;
727	}
728}
729
730
731static Boolean eap_sim_isDone(struct eap_sm *sm, void *priv)
732{
733	struct eap_sim_data *data = priv;
734	return data->state == SUCCESS || data->state == FAILURE;
735}
736
737
738static u8 * eap_sim_getKey(struct eap_sm *sm, void *priv, size_t *len)
739{
740	struct eap_sim_data *data = priv;
741	u8 *key;
742
743	if (data->state != SUCCESS)
744		return NULL;
745
746	key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
747	if (key == NULL)
748		return NULL;
749	os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
750	*len = EAP_SIM_KEYING_DATA_LEN;
751	return key;
752}
753
754
755static u8 * eap_sim_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
756{
757	struct eap_sim_data *data = priv;
758	u8 *key;
759
760	if (data->state != SUCCESS)
761		return NULL;
762
763	key = os_malloc(EAP_EMSK_LEN);
764	if (key == NULL)
765		return NULL;
766	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
767	*len = EAP_EMSK_LEN;
768	return key;
769}
770
771
772static Boolean eap_sim_isSuccess(struct eap_sm *sm, void *priv)
773{
774	struct eap_sim_data *data = priv;
775	return data->state == SUCCESS;
776}
777
778
779int eap_server_sim_register(void)
780{
781	struct eap_method *eap;
782	int ret;
783
784	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
785				      EAP_VENDOR_IETF, EAP_TYPE_SIM, "SIM");
786	if (eap == NULL)
787		return -1;
788
789	eap->init = eap_sim_init;
790	eap->reset = eap_sim_reset;
791	eap->buildReq = eap_sim_buildReq;
792	eap->check = eap_sim_check;
793	eap->process = eap_sim_process;
794	eap->isDone = eap_sim_isDone;
795	eap->getKey = eap_sim_getKey;
796	eap->isSuccess = eap_sim_isSuccess;
797	eap->get_emsk = eap_sim_get_emsk;
798
799	ret = eap_server_method_register(eap);
800	if (ret)
801		eap_server_method_free(eap);
802	return ret;
803}
804