eap_server_sim.c revision c5ec7f57ead87efa365800228aa0b09a12d9e6c4
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		wpa_printf(MSG_DEBUG, "   AT_PERMANENT_ID_REQ");
111		eap_sim_msg_add(msg, EAP_SIM_AT_PERMANENT_ID_REQ, 0, NULL, 0);
112	} else {
113		/*
114		 * RFC 4186, Chap. 4.2.4 recommends that identity from EAP is
115		 * ignored and the SIM/Start is used to request the identity.
116		 */
117		wpa_printf(MSG_DEBUG, "   AT_ANY_ID_REQ");
118		eap_sim_msg_add(msg, EAP_SIM_AT_ANY_ID_REQ, 0, NULL, 0);
119	}
120	wpa_printf(MSG_DEBUG, "   AT_VERSION_LIST");
121	ver[0] = 0;
122	ver[1] = EAP_SIM_VERSION;
123	eap_sim_msg_add(msg, EAP_SIM_AT_VERSION_LIST, sizeof(ver),
124			ver, sizeof(ver));
125	return eap_sim_msg_finish(msg, NULL, NULL, 0);
126}
127
128
129static int eap_sim_build_encr(struct eap_sm *sm, struct eap_sim_data *data,
130			      struct eap_sim_msg *msg, u16 counter,
131			      const u8 *nonce_s)
132{
133	os_free(data->next_pseudonym);
134	data->next_pseudonym =
135		eap_sim_db_get_next_pseudonym(sm->eap_sim_db_priv, 0);
136	os_free(data->next_reauth_id);
137	if (data->counter <= EAP_SIM_MAX_FAST_REAUTHS) {
138		data->next_reauth_id =
139			eap_sim_db_get_next_reauth_id(sm->eap_sim_db_priv, 0);
140	} else {
141		wpa_printf(MSG_DEBUG, "EAP-SIM: Max fast re-authentication "
142			   "count exceeded - force full authentication");
143		data->next_reauth_id = NULL;
144	}
145
146	if (data->next_pseudonym == NULL && data->next_reauth_id == NULL &&
147	    counter == 0 && nonce_s == NULL)
148		return 0;
149
150	wpa_printf(MSG_DEBUG, "   AT_IV");
151	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
152	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
153
154	if (counter > 0) {
155		wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)", counter);
156		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
157	}
158
159	if (nonce_s) {
160		wpa_printf(MSG_DEBUG, "   *AT_NONCE_S");
161		eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_S, 0, nonce_s,
162				EAP_SIM_NONCE_S_LEN);
163	}
164
165	if (data->next_pseudonym) {
166		wpa_printf(MSG_DEBUG, "   *AT_NEXT_PSEUDONYM (%s)",
167			   data->next_pseudonym);
168		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_PSEUDONYM,
169				os_strlen(data->next_pseudonym),
170				(u8 *) data->next_pseudonym,
171				os_strlen(data->next_pseudonym));
172	}
173
174	if (data->next_reauth_id) {
175		wpa_printf(MSG_DEBUG, "   *AT_NEXT_REAUTH_ID (%s)",
176			   data->next_reauth_id);
177		eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_REAUTH_ID,
178				os_strlen(data->next_reauth_id),
179				(u8 *) data->next_reauth_id,
180				os_strlen(data->next_reauth_id));
181	}
182
183	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
184		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt "
185			   "AT_ENCR_DATA");
186		return -1;
187	}
188
189	return 0;
190}
191
192
193static struct wpabuf * eap_sim_build_challenge(struct eap_sm *sm,
194					       struct eap_sim_data *data,
195					       u8 id)
196{
197	struct eap_sim_msg *msg;
198
199	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Challenge");
200	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
201			       EAP_SIM_SUBTYPE_CHALLENGE);
202	wpa_printf(MSG_DEBUG, "   AT_RAND");
203	eap_sim_msg_add(msg, EAP_SIM_AT_RAND, 0, (u8 *) data->rand,
204			data->num_chal * GSM_RAND_LEN);
205
206	if (eap_sim_build_encr(sm, data, msg, 0, NULL)) {
207		eap_sim_msg_free(msg);
208		return NULL;
209	}
210
211	if (sm->eap_sim_aka_result_ind) {
212		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
213		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
214	}
215
216	wpa_printf(MSG_DEBUG, "   AT_MAC");
217	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
218	return eap_sim_msg_finish(msg, data->k_aut, data->nonce_mt,
219				  EAP_SIM_NONCE_MT_LEN);
220}
221
222
223static struct wpabuf * eap_sim_build_reauth(struct eap_sm *sm,
224					    struct eap_sim_data *data, u8 id)
225{
226	struct eap_sim_msg *msg;
227
228	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Re-authentication");
229
230	if (random_get_bytes(data->nonce_s, EAP_SIM_NONCE_S_LEN))
231		return NULL;
232	wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: NONCE_S",
233			data->nonce_s, EAP_SIM_NONCE_S_LEN);
234
235	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
236			    data->emsk);
237	eap_sim_derive_keys_reauth(data->counter, sm->identity,
238				   sm->identity_len, data->nonce_s, data->mk,
239				   data->msk, data->emsk);
240
241	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
242			       EAP_SIM_SUBTYPE_REAUTHENTICATION);
243
244	if (eap_sim_build_encr(sm, data, msg, data->counter, data->nonce_s)) {
245		eap_sim_msg_free(msg);
246		return NULL;
247	}
248
249	if (sm->eap_sim_aka_result_ind) {
250		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
251		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
252	}
253
254	wpa_printf(MSG_DEBUG, "   AT_MAC");
255	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
256	return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
257}
258
259
260static struct wpabuf * eap_sim_build_notification(struct eap_sm *sm,
261						  struct eap_sim_data *data,
262						  u8 id)
263{
264	struct eap_sim_msg *msg;
265
266	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Notification");
267	msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
268			       EAP_SIM_SUBTYPE_NOTIFICATION);
269	wpa_printf(MSG_DEBUG, "   AT_NOTIFICATION (%d)", data->notification);
270	eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, data->notification,
271			NULL, 0);
272	if (data->use_result_ind) {
273		if (data->reauth) {
274			wpa_printf(MSG_DEBUG, "   AT_IV");
275			wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
276			eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
277						   EAP_SIM_AT_ENCR_DATA);
278			wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)",
279				   data->counter);
280			eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
281					NULL, 0);
282
283			if (eap_sim_msg_add_encr_end(msg, data->k_encr,
284						     EAP_SIM_AT_PADDING)) {
285				wpa_printf(MSG_WARNING, "EAP-SIM: Failed to "
286					   "encrypt AT_ENCR_DATA");
287				eap_sim_msg_free(msg);
288				return NULL;
289			}
290		}
291
292		wpa_printf(MSG_DEBUG, "   AT_MAC");
293		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
294	}
295	return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
296}
297
298
299static struct wpabuf * eap_sim_buildReq(struct eap_sm *sm, void *priv, u8 id)
300{
301	struct eap_sim_data *data = priv;
302
303	switch (data->state) {
304	case START:
305		return eap_sim_build_start(sm, data, id);
306	case CHALLENGE:
307		return eap_sim_build_challenge(sm, data, id);
308	case REAUTH:
309		return eap_sim_build_reauth(sm, data, id);
310	case NOTIFICATION:
311		return eap_sim_build_notification(sm, data, id);
312	default:
313		wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
314			   "buildReq", data->state);
315		break;
316	}
317	return NULL;
318}
319
320
321static Boolean eap_sim_check(struct eap_sm *sm, void *priv,
322			     struct wpabuf *respData)
323{
324	struct eap_sim_data *data = priv;
325	const u8 *pos;
326	size_t len;
327	u8 subtype;
328
329	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, respData, &len);
330	if (pos == NULL || len < 3) {
331		wpa_printf(MSG_INFO, "EAP-SIM: Invalid frame");
332		return TRUE;
333	}
334	subtype = *pos;
335
336	if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR)
337		return FALSE;
338
339	switch (data->state) {
340	case START:
341		if (subtype != EAP_SIM_SUBTYPE_START) {
342			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
343				   "subtype %d", subtype);
344			return TRUE;
345		}
346		break;
347	case CHALLENGE:
348		if (subtype != EAP_SIM_SUBTYPE_CHALLENGE) {
349			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
350				   "subtype %d", subtype);
351			return TRUE;
352		}
353		break;
354	case REAUTH:
355		if (subtype != EAP_SIM_SUBTYPE_REAUTHENTICATION) {
356			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
357				   "subtype %d", subtype);
358			return TRUE;
359		}
360		break;
361	case NOTIFICATION:
362		if (subtype != EAP_SIM_SUBTYPE_NOTIFICATION) {
363			wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
364				   "subtype %d", subtype);
365			return TRUE;
366		}
367		break;
368	default:
369		wpa_printf(MSG_INFO, "EAP-SIM: Unexpected state (%d) for "
370			   "processing a response", data->state);
371		return TRUE;
372	}
373
374	return FALSE;
375}
376
377
378static int eap_sim_supported_ver(struct eap_sim_data *data, int version)
379{
380	return version == EAP_SIM_VERSION;
381}
382
383
384static void eap_sim_process_start(struct eap_sm *sm,
385				  struct eap_sim_data *data,
386				  struct wpabuf *respData,
387				  struct eap_sim_attrs *attr)
388{
389	const u8 *identity;
390	size_t identity_len;
391	u8 ver_list[2];
392
393	wpa_printf(MSG_DEBUG, "EAP-SIM: Receive start response");
394
395	if (attr->identity) {
396		os_free(sm->identity);
397		sm->identity = os_malloc(attr->identity_len);
398		if (sm->identity) {
399			os_memcpy(sm->identity, attr->identity,
400				  attr->identity_len);
401			sm->identity_len = attr->identity_len;
402		}
403	}
404
405	identity = NULL;
406	identity_len = 0;
407
408	if (sm->identity && sm->identity_len > 0 &&
409	    sm->identity[0] == EAP_SIM_PERMANENT_PREFIX) {
410		identity = sm->identity;
411		identity_len = sm->identity_len;
412	} else {
413		identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv,
414						    sm->identity,
415						    sm->identity_len,
416						    &identity_len);
417		if (identity == NULL) {
418			data->reauth = eap_sim_db_get_reauth_entry(
419				sm->eap_sim_db_priv, sm->identity,
420				sm->identity_len);
421			if (data->reauth) {
422				wpa_printf(MSG_DEBUG, "EAP-SIM: Using fast "
423					   "re-authentication");
424				identity = data->reauth->identity;
425				identity_len = data->reauth->identity_len;
426				data->counter = data->reauth->counter;
427				os_memcpy(data->mk, data->reauth->mk,
428					  EAP_SIM_MK_LEN);
429			}
430		}
431	}
432
433	if (identity == NULL) {
434		wpa_printf(MSG_DEBUG, "EAP-SIM: Could not get proper permanent"
435			   " user name");
436		eap_sim_state(data, FAILURE);
437		return;
438	}
439
440	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity",
441			  identity, identity_len);
442
443	if (data->reauth) {
444		eap_sim_state(data, REAUTH);
445		return;
446	}
447
448	if (attr->nonce_mt == NULL || attr->selected_version < 0) {
449		wpa_printf(MSG_DEBUG, "EAP-SIM: Start/Response missing "
450			   "required attributes");
451		eap_sim_state(data, FAILURE);
452		return;
453	}
454
455	if (!eap_sim_supported_ver(data, attr->selected_version)) {
456		wpa_printf(MSG_DEBUG, "EAP-SIM: Peer selected unsupported "
457			   "version %d", attr->selected_version);
458		eap_sim_state(data, FAILURE);
459		return;
460	}
461
462	data->counter = 0; /* reset re-auth counter since this is full auth */
463	data->reauth = NULL;
464
465	data->num_chal = eap_sim_db_get_gsm_triplets(
466		sm->eap_sim_db_priv, identity, identity_len,
467		EAP_SIM_MAX_CHAL,
468		(u8 *) data->rand, (u8 *) data->kc, (u8 *) data->sres, sm);
469	if (data->num_chal == EAP_SIM_DB_PENDING) {
470		wpa_printf(MSG_DEBUG, "EAP-SIM: GSM authentication triplets "
471			   "not yet available - pending request");
472		sm->method_pending = METHOD_PENDING_WAIT;
473		return;
474	}
475	if (data->num_chal < 2) {
476		wpa_printf(MSG_INFO, "EAP-SIM: Failed to get GSM "
477			   "authentication triplets for the peer");
478		eap_sim_state(data, FAILURE);
479		return;
480	}
481
482	identity_len = sm->identity_len;
483	while (identity_len > 0 && sm->identity[identity_len - 1] == '\0') {
484		wpa_printf(MSG_DEBUG, "EAP-SIM: Workaround - drop last null "
485			   "character from identity");
486		identity_len--;
487	}
488	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity for MK derivation",
489			  sm->identity, identity_len);
490
491	os_memcpy(data->nonce_mt, attr->nonce_mt, EAP_SIM_NONCE_MT_LEN);
492	WPA_PUT_BE16(ver_list, EAP_SIM_VERSION);
493	eap_sim_derive_mk(sm->identity, identity_len, attr->nonce_mt,
494			  attr->selected_version, ver_list, sizeof(ver_list),
495			  data->num_chal, (const u8 *) data->kc, data->mk);
496	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
497			    data->emsk);
498
499	eap_sim_state(data, CHALLENGE);
500}
501
502
503static void eap_sim_process_challenge(struct eap_sm *sm,
504				      struct eap_sim_data *data,
505				      struct wpabuf *respData,
506				      struct eap_sim_attrs *attr)
507{
508	const u8 *identity;
509	size_t identity_len;
510
511	if (attr->mac == NULL ||
512	    eap_sim_verify_mac(data->k_aut, respData, attr->mac,
513			       (u8 *) data->sres,
514			       data->num_chal * EAP_SIM_SRES_LEN)) {
515		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
516			   "did not include valid AT_MAC");
517		eap_sim_state(data, FAILURE);
518		return;
519	}
520
521	wpa_printf(MSG_DEBUG, "EAP-SIM: Challenge response includes the "
522		   "correct AT_MAC");
523	if (sm->eap_sim_aka_result_ind && attr->result_ind) {
524		data->use_result_ind = 1;
525		data->notification = EAP_SIM_SUCCESS;
526		eap_sim_state(data, NOTIFICATION);
527	} else
528		eap_sim_state(data, SUCCESS);
529
530	identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv, sm->identity,
531					    sm->identity_len, &identity_len);
532	if (identity == NULL) {
533		identity = sm->identity;
534		identity_len = sm->identity_len;
535	}
536
537	if (data->next_pseudonym) {
538		eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
539					 identity_len,
540					 data->next_pseudonym);
541		data->next_pseudonym = NULL;
542	}
543	if (data->next_reauth_id) {
544		eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
545				      identity_len,
546				      data->next_reauth_id, data->counter + 1,
547				      data->mk);
548		data->next_reauth_id = NULL;
549	}
550}
551
552
553static void eap_sim_process_reauth(struct eap_sm *sm,
554				   struct eap_sim_data *data,
555				   struct wpabuf *respData,
556				   struct eap_sim_attrs *attr)
557{
558	struct eap_sim_attrs eattr;
559	u8 *decrypted = NULL;
560	const u8 *identity, *id2;
561	size_t identity_len, id2_len;
562
563	if (attr->mac == NULL ||
564	    eap_sim_verify_mac(data->k_aut, respData, attr->mac, data->nonce_s,
565			       EAP_SIM_NONCE_S_LEN)) {
566		wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
567			   "did not include valid AT_MAC");
568		goto fail;
569	}
570
571	if (attr->encr_data == NULL || attr->iv == NULL) {
572		wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication "
573			   "message did not include encrypted data");
574		goto fail;
575	}
576
577	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
578				       attr->encr_data_len, attr->iv, &eattr,
579				       0);
580	if (decrypted == NULL) {
581		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted "
582			   "data from reauthentication message");
583		goto fail;
584	}
585
586	if (eattr.counter != data->counter) {
587		wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
588			   "used incorrect counter %u, expected %u",
589			   eattr.counter, data->counter);
590		goto fail;
591	}
592	os_free(decrypted);
593	decrypted = NULL;
594
595	wpa_printf(MSG_DEBUG, "EAP-SIM: Re-authentication response includes "
596		   "the correct AT_MAC");
597	if (sm->eap_sim_aka_result_ind && attr->result_ind) {
598		data->use_result_ind = 1;
599		data->notification = EAP_SIM_SUCCESS;
600		eap_sim_state(data, NOTIFICATION);
601	} else
602		eap_sim_state(data, SUCCESS);
603
604	if (data->reauth) {
605		identity = data->reauth->identity;
606		identity_len = data->reauth->identity_len;
607	} else {
608		identity = sm->identity;
609		identity_len = sm->identity_len;
610	}
611
612	id2 = eap_sim_db_get_permanent(sm->eap_sim_db_priv, identity,
613				       identity_len, &id2_len);
614	if (id2) {
615		identity = id2;
616		identity_len = id2_len;
617	}
618
619	if (data->next_pseudonym) {
620		eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
621					 identity_len, data->next_pseudonym);
622		data->next_pseudonym = NULL;
623	}
624	if (data->next_reauth_id) {
625		eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
626				      identity_len, data->next_reauth_id,
627				      data->counter + 1, data->mk);
628		data->next_reauth_id = NULL;
629	} else {
630		eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
631		data->reauth = NULL;
632	}
633
634	return;
635
636fail:
637	eap_sim_state(data, FAILURE);
638	eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
639	data->reauth = NULL;
640	os_free(decrypted);
641}
642
643
644static void eap_sim_process_client_error(struct eap_sm *sm,
645					 struct eap_sim_data *data,
646					 struct wpabuf *respData,
647					 struct eap_sim_attrs *attr)
648{
649	wpa_printf(MSG_DEBUG, "EAP-SIM: Client reported error %d",
650		   attr->client_error_code);
651	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
652		eap_sim_state(data, SUCCESS);
653	else
654		eap_sim_state(data, FAILURE);
655}
656
657
658static void eap_sim_process_notification(struct eap_sm *sm,
659					 struct eap_sim_data *data,
660					 struct wpabuf *respData,
661					 struct eap_sim_attrs *attr)
662{
663	wpa_printf(MSG_DEBUG, "EAP-SIM: Client replied to notification");
664	if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
665		eap_sim_state(data, SUCCESS);
666	else
667		eap_sim_state(data, FAILURE);
668}
669
670
671static void eap_sim_process(struct eap_sm *sm, void *priv,
672			    struct wpabuf *respData)
673{
674	struct eap_sim_data *data = priv;
675	const u8 *pos, *end;
676	u8 subtype;
677	size_t len;
678	struct eap_sim_attrs attr;
679
680	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, respData, &len);
681	if (pos == NULL || len < 3)
682		return;
683
684	end = pos + len;
685	subtype = *pos;
686	pos += 3;
687
688	if (eap_sim_parse_attr(pos, end, &attr, 0, 0)) {
689		wpa_printf(MSG_DEBUG, "EAP-SIM: Failed to parse attributes");
690		eap_sim_state(data, FAILURE);
691		return;
692	}
693
694	if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR) {
695		eap_sim_process_client_error(sm, data, respData, &attr);
696		return;
697	}
698
699	switch (data->state) {
700	case START:
701		eap_sim_process_start(sm, data, respData, &attr);
702		break;
703	case CHALLENGE:
704		eap_sim_process_challenge(sm, data, respData, &attr);
705		break;
706	case REAUTH:
707		eap_sim_process_reauth(sm, data, respData, &attr);
708		break;
709	case NOTIFICATION:
710		eap_sim_process_notification(sm, data, respData, &attr);
711		break;
712	default:
713		wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
714			   "process", data->state);
715		break;
716	}
717}
718
719
720static Boolean eap_sim_isDone(struct eap_sm *sm, void *priv)
721{
722	struct eap_sim_data *data = priv;
723	return data->state == SUCCESS || data->state == FAILURE;
724}
725
726
727static u8 * eap_sim_getKey(struct eap_sm *sm, void *priv, size_t *len)
728{
729	struct eap_sim_data *data = priv;
730	u8 *key;
731
732	if (data->state != SUCCESS)
733		return NULL;
734
735	key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
736	if (key == NULL)
737		return NULL;
738	os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
739	*len = EAP_SIM_KEYING_DATA_LEN;
740	return key;
741}
742
743
744static u8 * eap_sim_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
745{
746	struct eap_sim_data *data = priv;
747	u8 *key;
748
749	if (data->state != SUCCESS)
750		return NULL;
751
752	key = os_malloc(EAP_EMSK_LEN);
753	if (key == NULL)
754		return NULL;
755	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
756	*len = EAP_EMSK_LEN;
757	return key;
758}
759
760
761static Boolean eap_sim_isSuccess(struct eap_sm *sm, void *priv)
762{
763	struct eap_sim_data *data = priv;
764	return data->state == SUCCESS;
765}
766
767
768int eap_server_sim_register(void)
769{
770	struct eap_method *eap;
771	int ret;
772
773	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
774				      EAP_VENDOR_IETF, EAP_TYPE_SIM, "SIM");
775	if (eap == NULL)
776		return -1;
777
778	eap->init = eap_sim_init;
779	eap->reset = eap_sim_reset;
780	eap->buildReq = eap_sim_buildReq;
781	eap->check = eap_sim_check;
782	eap->process = eap_sim_process;
783	eap->isDone = eap_sim_isDone;
784	eap->getKey = eap_sim_getKey;
785	eap->isSuccess = eap_sim_isSuccess;
786	eap->get_emsk = eap_sim_get_emsk;
787
788	ret = eap_server_method_register(eap);
789	if (ret)
790		eap_server_method_free(eap);
791	return ret;
792}
793