1 /*
2  * EAP peer method: EAP-SIM (RFC 4186)
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/milenage.h"
14 #include "crypto/random.h"
15 #include "eap_peer/eap_i.h"
16 #include "eap_config.h"
17 #include "eap_common/eap_sim_common.h"
18 
19 
20 struct eap_sim_data {
21 	u8 *ver_list;
22 	size_t ver_list_len;
23 	int selected_version;
24 	size_t min_num_chal, num_chal;
25 
26 	u8 kc[3][EAP_SIM_KC_LEN];
27 	u8 sres[3][EAP_SIM_SRES_LEN];
28 	u8 nonce_mt[EAP_SIM_NONCE_MT_LEN], nonce_s[EAP_SIM_NONCE_S_LEN];
29 	u8 mk[EAP_SIM_MK_LEN];
30 	u8 k_aut[EAP_SIM_K_AUT_LEN];
31 	u8 k_encr[EAP_SIM_K_ENCR_LEN];
32 	u8 msk[EAP_SIM_KEYING_DATA_LEN];
33 	u8 emsk[EAP_EMSK_LEN];
34 	u8 rand[3][GSM_RAND_LEN];
35 	u8 reauth_mac[EAP_SIM_MAC_LEN];
36 
37 	int num_id_req, num_notification;
38 	u8 *pseudonym;
39 	size_t pseudonym_len;
40 	u8 *reauth_id;
41 	size_t reauth_id_len;
42 	int reauth;
43 	unsigned int counter, counter_too_small;
44 	u8 *last_eap_identity;
45 	size_t last_eap_identity_len;
46 	enum {
47 		CONTINUE, RESULT_SUCCESS, SUCCESS, FAILURE
48 	} state;
49 	int result_ind, use_result_ind;
50 	int use_pseudonym;
51 	int error_code;
52 };
53 
54 
55 #ifndef CONFIG_NO_STDOUT_DEBUG
eap_sim_state_txt(int state)56 static const char * eap_sim_state_txt(int state)
57 {
58 	switch (state) {
59 	case CONTINUE:
60 		return "CONTINUE";
61 	case RESULT_SUCCESS:
62 		return "RESULT_SUCCESS";
63 	case SUCCESS:
64 		return "SUCCESS";
65 	case FAILURE:
66 		return "FAILURE";
67 	default:
68 		return "?";
69 	}
70 }
71 #endif /* CONFIG_NO_STDOUT_DEBUG */
72 
73 
eap_sim_state(struct eap_sim_data * data,int state)74 static void eap_sim_state(struct eap_sim_data *data, int state)
75 {
76 	wpa_printf(MSG_DEBUG, "EAP-SIM: %s -> %s",
77 		   eap_sim_state_txt(data->state),
78 		   eap_sim_state_txt(state));
79 	data->state = state;
80 }
81 
82 
eap_sim_init(struct eap_sm * sm)83 static void * eap_sim_init(struct eap_sm *sm)
84 {
85 	struct eap_sim_data *data;
86 	struct eap_peer_config *config = eap_get_config(sm);
87 
88 	data = os_zalloc(sizeof(*data));
89 	if (data == NULL)
90 		return NULL;
91 
92 	if (random_get_bytes(data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) {
93 		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to get random data "
94 			   "for NONCE_MT");
95 		os_free(data);
96 		return NULL;
97 	}
98 
99 	/* Zero is a valid error code, so we need to initialize */
100 	data->error_code = NO_EAP_METHOD_ERROR;
101 
102 	data->min_num_chal = 2;
103 	if (config && config->phase1) {
104 		char *pos = os_strstr(config->phase1, "sim_min_num_chal=");
105 		if (pos) {
106 			data->min_num_chal = atoi(pos + 17);
107 			if (data->min_num_chal < 2 || data->min_num_chal > 3) {
108 				wpa_printf(MSG_WARNING, "EAP-SIM: Invalid "
109 					   "sim_min_num_chal configuration "
110 					   "(%lu, expected 2 or 3)",
111 					   (unsigned long) data->min_num_chal);
112 				os_free(data);
113 				return NULL;
114 			}
115 			wpa_printf(MSG_DEBUG, "EAP-SIM: Set minimum number of "
116 				   "challenges to %lu",
117 				   (unsigned long) data->min_num_chal);
118 		}
119 
120 		data->result_ind = os_strstr(config->phase1, "result_ind=1") !=
121 			NULL;
122 	}
123 
124 	data->use_pseudonym = !sm->init_phase2;
125 	if (config && config->anonymous_identity && data->use_pseudonym) {
126 		data->pseudonym = os_malloc(config->anonymous_identity_len);
127 		if (data->pseudonym) {
128 			os_memcpy(data->pseudonym, config->anonymous_identity,
129 				  config->anonymous_identity_len);
130 			data->pseudonym_len = config->anonymous_identity_len;
131 		}
132 	}
133 
134 	eap_sim_state(data, CONTINUE);
135 
136 	return data;
137 }
138 
139 
eap_sim_clear_keys(struct eap_sim_data * data,int reauth)140 static void eap_sim_clear_keys(struct eap_sim_data *data, int reauth)
141 {
142 	if (!reauth) {
143 		os_memset(data->mk, 0, EAP_SIM_MK_LEN);
144 		os_memset(data->k_aut, 0, EAP_SIM_K_AUT_LEN);
145 		os_memset(data->k_encr, 0, EAP_SIM_K_ENCR_LEN);
146 	}
147 	os_memset(data->kc, 0, 3 * EAP_SIM_KC_LEN);
148 	os_memset(data->sres, 0, 3 * EAP_SIM_SRES_LEN);
149 	os_memset(data->msk, 0, EAP_SIM_KEYING_DATA_LEN);
150 	os_memset(data->emsk, 0, EAP_EMSK_LEN);
151 }
152 
153 
eap_sim_deinit(struct eap_sm * sm,void * priv)154 static void eap_sim_deinit(struct eap_sm *sm, void *priv)
155 {
156 	struct eap_sim_data *data = priv;
157 	if (data) {
158 		os_free(data->ver_list);
159 		os_free(data->pseudonym);
160 		os_free(data->reauth_id);
161 		os_free(data->last_eap_identity);
162 		eap_sim_clear_keys(data, 0);
163 		os_free(data);
164 	}
165 }
166 
167 
eap_sim_ext_sim_req(struct eap_sm * sm,struct eap_sim_data * data)168 static int eap_sim_ext_sim_req(struct eap_sm *sm, struct eap_sim_data *data)
169 {
170 	char req[200], *pos, *end;
171 	size_t i;
172 
173 	wpa_printf(MSG_DEBUG, "EAP-SIM: Use external SIM processing");
174 	pos = req;
175 	end = pos + sizeof(req);
176 	pos += os_snprintf(pos, end - pos, "GSM-AUTH");
177 	for (i = 0; i < data->num_chal; i++) {
178 		pos += os_snprintf(pos, end - pos, ":");
179 		pos += wpa_snprintf_hex(pos, end - pos, data->rand[i],
180 					GSM_RAND_LEN);
181 	}
182 
183 	eap_sm_request_sim(sm, req);
184 	return 1;
185 }
186 
187 
eap_sim_ext_sim_result(struct eap_sm * sm,struct eap_sim_data * data,struct eap_peer_config * conf)188 static int eap_sim_ext_sim_result(struct eap_sm *sm, struct eap_sim_data *data,
189 				  struct eap_peer_config *conf)
190 {
191 	char *resp, *pos;
192 	size_t i;
193 
194 	wpa_printf(MSG_DEBUG,
195 		   "EAP-SIM: Use result from external SIM processing");
196 
197 	resp = conf->external_sim_resp;
198 	conf->external_sim_resp = NULL;
199 
200 	if (os_strncmp(resp, "GSM-AUTH:", 9) != 0) {
201 		wpa_printf(MSG_DEBUG, "EAP-SIM: Unrecognized external SIM processing response");
202 		os_free(resp);
203 		return -1;
204 	}
205 
206 	pos = resp + 9;
207 	for (i = 0; i < data->num_chal; i++) {
208 		wpa_hexdump(MSG_DEBUG, "EAP-SIM: RAND",
209 			    data->rand[i], GSM_RAND_LEN);
210 
211 		if (hexstr2bin(pos, data->kc[i], EAP_SIM_KC_LEN) < 0)
212 			goto invalid;
213 		wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: Kc",
214 				data->kc[i], EAP_SIM_KC_LEN);
215 		pos += EAP_SIM_KC_LEN * 2;
216 		if (*pos != ':')
217 			goto invalid;
218 		pos++;
219 
220 		if (hexstr2bin(pos, data->sres[i], EAP_SIM_SRES_LEN) < 0)
221 			goto invalid;
222 		wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: SRES",
223 				data->sres[i], EAP_SIM_SRES_LEN);
224 		pos += EAP_SIM_SRES_LEN * 2;
225 		if (i + 1 < data->num_chal) {
226 			if (*pos != ':')
227 				goto invalid;
228 			pos++;
229 		}
230 	}
231 
232 	os_free(resp);
233 	return 0;
234 
235 invalid:
236 	wpa_printf(MSG_DEBUG, "EAP-SIM: Invalid external SIM processing GSM-AUTH response");
237 	os_free(resp);
238 	return -1;
239 }
240 
241 
eap_sim_gsm_auth(struct eap_sm * sm,struct eap_sim_data * data)242 static int eap_sim_gsm_auth(struct eap_sm *sm, struct eap_sim_data *data)
243 {
244 	struct eap_peer_config *conf;
245 
246 	wpa_printf(MSG_DEBUG, "EAP-SIM: GSM authentication algorithm");
247 
248 	conf = eap_get_config(sm);
249 	if (conf == NULL)
250 		return -1;
251 
252 	if (sm->external_sim) {
253 		if (conf->external_sim_resp)
254 			return eap_sim_ext_sim_result(sm, data, conf);
255 		else
256 			return eap_sim_ext_sim_req(sm, data);
257 	}
258 
259 #ifdef PCSC_FUNCS
260 	if (conf->pcsc) {
261 		if (scard_gsm_auth(sm->scard_ctx, data->rand[0],
262 				   data->sres[0], data->kc[0]) ||
263 		    scard_gsm_auth(sm->scard_ctx, data->rand[1],
264 				   data->sres[1], data->kc[1]) ||
265 		    (data->num_chal > 2 &&
266 		     scard_gsm_auth(sm->scard_ctx, data->rand[2],
267 				    data->sres[2], data->kc[2]))) {
268 			wpa_printf(MSG_DEBUG, "EAP-SIM: GSM SIM "
269 				   "authentication could not be completed");
270 			return -1;
271 		}
272 		return 0;
273 	}
274 #endif /* PCSC_FUNCS */
275 
276 #ifdef CONFIG_SIM_SIMULATOR
277 	if (conf->password) {
278 		u8 opc[16], k[16];
279 		const char *pos;
280 		size_t i;
281 		wpa_printf(MSG_DEBUG, "EAP-SIM: Use internal GSM-Milenage "
282 			   "implementation for authentication");
283 		if (conf->password_len < 65) {
284 			wpa_printf(MSG_DEBUG, "EAP-SIM: invalid GSM-Milenage "
285 				   "password");
286 			return -1;
287 		}
288 		pos = (const char *) conf->password;
289 		if (hexstr2bin(pos, k, 16))
290 			return -1;
291 		pos += 32;
292 		if (*pos != ':')
293 			return -1;
294 		pos++;
295 
296 		if (hexstr2bin(pos, opc, 16))
297 			return -1;
298 
299 		for (i = 0; i < data->num_chal; i++) {
300 			if (gsm_milenage(opc, k, data->rand[i],
301 					 data->sres[i], data->kc[i])) {
302 				wpa_printf(MSG_DEBUG, "EAP-SIM: "
303 					   "GSM-Milenage authentication "
304 					   "could not be completed");
305 				return -1;
306 			}
307 			wpa_hexdump(MSG_DEBUG, "EAP-SIM: RAND",
308 				    data->rand[i], GSM_RAND_LEN);
309 			wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: SRES",
310 					data->sres[i], EAP_SIM_SRES_LEN);
311 			wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: Kc",
312 					data->kc[i], EAP_SIM_KC_LEN);
313 		}
314 		return 0;
315 	}
316 #endif /* CONFIG_SIM_SIMULATOR */
317 
318 #ifdef CONFIG_SIM_HARDCODED
319 	/* These hardcoded Kc and SRES values are used for testing. RAND to
320 	 * KC/SREC mapping is very bogus as far as real authentication is
321 	 * concerned, but it is quite useful for cases where the AS is rotating
322 	 * the order of pre-configured values. */
323 	{
324 		size_t i;
325 
326 		wpa_printf(MSG_DEBUG, "EAP-SIM: Use hardcoded Kc and SRES "
327 			   "values for testing");
328 
329 		for (i = 0; i < data->num_chal; i++) {
330 			if (data->rand[i][0] == 0xaa) {
331 				os_memcpy(data->kc[i],
332 					  "\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7",
333 					  EAP_SIM_KC_LEN);
334 				os_memcpy(data->sres[i], "\xd1\xd2\xd3\xd4",
335 					  EAP_SIM_SRES_LEN);
336 			} else if (data->rand[i][0] == 0xbb) {
337 				os_memcpy(data->kc[i],
338 					  "\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7",
339 					  EAP_SIM_KC_LEN);
340 				os_memcpy(data->sres[i], "\xe1\xe2\xe3\xe4",
341 					  EAP_SIM_SRES_LEN);
342 			} else {
343 				os_memcpy(data->kc[i],
344 					  "\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7",
345 					  EAP_SIM_KC_LEN);
346 				os_memcpy(data->sres[i], "\xf1\xf2\xf3\xf4",
347 					  EAP_SIM_SRES_LEN);
348 			}
349 		}
350 	}
351 
352 	return 0;
353 
354 #else /* CONFIG_SIM_HARDCODED */
355 
356 	wpa_printf(MSG_DEBUG, "EAP-SIM: No GSM authentication algorithm "
357 		   "enabled");
358 	return -1;
359 
360 #endif /* CONFIG_SIM_HARDCODED */
361 }
362 
363 
eap_sim_supported_ver(int version)364 static int eap_sim_supported_ver(int version)
365 {
366 	return version == EAP_SIM_VERSION;
367 }
368 
369 
370 #define CLEAR_PSEUDONYM	0x01
371 #define CLEAR_REAUTH_ID	0x02
372 #define CLEAR_EAP_ID	0x04
373 
eap_sim_clear_identities(struct eap_sm * sm,struct eap_sim_data * data,int id)374 static void eap_sim_clear_identities(struct eap_sm *sm,
375 				     struct eap_sim_data *data, int id)
376 {
377 	if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
378 		wpa_printf(MSG_DEBUG, "EAP-SIM: forgetting old pseudonym");
379 		os_free(data->pseudonym);
380 		data->pseudonym = NULL;
381 		data->pseudonym_len = 0;
382 		if (data->use_pseudonym)
383 			eap_set_anon_id(sm, NULL, 0);
384 	}
385 	if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
386 		wpa_printf(MSG_DEBUG, "EAP-SIM: forgetting old reauth_id");
387 		os_free(data->reauth_id);
388 		data->reauth_id = NULL;
389 		data->reauth_id_len = 0;
390 	}
391 	if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
392 		wpa_printf(MSG_DEBUG, "EAP-SIM: forgetting old eap_id");
393 		os_free(data->last_eap_identity);
394 		data->last_eap_identity = NULL;
395 		data->last_eap_identity_len = 0;
396 	}
397 }
398 
399 
eap_sim_learn_ids(struct eap_sm * sm,struct eap_sim_data * data,struct eap_sim_attrs * attr)400 static int eap_sim_learn_ids(struct eap_sm *sm, struct eap_sim_data *data,
401 			     struct eap_sim_attrs *attr)
402 {
403 	if (attr->next_pseudonym) {
404 		const u8 *identity = NULL;
405 		size_t identity_len = 0;
406 		const u8 *realm = NULL;
407 		size_t realm_len = 0;
408 
409 		wpa_hexdump_ascii(MSG_DEBUG,
410 				  "EAP-SIM: (encr) AT_NEXT_PSEUDONYM",
411 				  attr->next_pseudonym,
412 				  attr->next_pseudonym_len);
413 		os_free(data->pseudonym);
414 		/* Look for the realm of the permanent identity */
415 		identity = eap_get_config_identity(sm, &identity_len);
416 		if (identity) {
417 			for (realm = identity, realm_len = identity_len;
418 			     realm_len > 0; realm_len--, realm++) {
419 				if (*realm == '@')
420 					break;
421 			}
422 		}
423 		data->pseudonym = os_malloc(attr->next_pseudonym_len +
424 					    realm_len);
425 		if (data->pseudonym == NULL) {
426 			wpa_printf(MSG_INFO, "EAP-SIM: (encr) No memory for "
427 				   "next pseudonym");
428 			data->pseudonym_len = 0;
429 			return -1;
430 		}
431 		os_memcpy(data->pseudonym, attr->next_pseudonym,
432 			  attr->next_pseudonym_len);
433 		if (realm_len) {
434 			os_memcpy(data->pseudonym + attr->next_pseudonym_len,
435 				  realm, realm_len);
436 		}
437 		data->pseudonym_len = attr->next_pseudonym_len + realm_len;
438 		if (data->use_pseudonym)
439 			eap_set_anon_id(sm, data->pseudonym,
440 					data->pseudonym_len);
441 	}
442 
443 	if (attr->next_reauth_id) {
444 		os_free(data->reauth_id);
445 		data->reauth_id = os_memdup(attr->next_reauth_id,
446 					    attr->next_reauth_id_len);
447 		if (data->reauth_id == NULL) {
448 			wpa_printf(MSG_INFO, "EAP-SIM: (encr) No memory for "
449 				   "next reauth_id");
450 			data->reauth_id_len = 0;
451 			return -1;
452 		}
453 		data->reauth_id_len = attr->next_reauth_id_len;
454 		wpa_hexdump_ascii(MSG_DEBUG,
455 				  "EAP-SIM: (encr) AT_NEXT_REAUTH_ID",
456 				  data->reauth_id,
457 				  data->reauth_id_len);
458 	}
459 
460 	return 0;
461 }
462 
463 
eap_sim_client_error(struct eap_sim_data * data,u8 id,int err)464 static struct wpabuf * eap_sim_client_error(struct eap_sim_data *data, u8 id,
465 					    int err)
466 {
467 	struct eap_sim_msg *msg;
468 
469 	eap_sim_state(data, FAILURE);
470 	data->num_id_req = 0;
471 	data->num_notification = 0;
472 
473 	wpa_printf(MSG_DEBUG, "EAP-SIM: Send Client-Error (error code %d)",
474 		   err);
475 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, EAP_TYPE_SIM,
476 			       EAP_SIM_SUBTYPE_CLIENT_ERROR);
477 	eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
478 	return eap_sim_msg_finish(msg, EAP_TYPE_SIM, NULL, NULL, 0);
479 }
480 
481 
eap_sim_response_start(struct eap_sm * sm,struct eap_sim_data * data,u8 id,enum eap_sim_id_req id_req)482 static struct wpabuf * eap_sim_response_start(struct eap_sm *sm,
483 					      struct eap_sim_data *data, u8 id,
484 					      enum eap_sim_id_req id_req)
485 {
486 	const u8 *identity = NULL;
487 	size_t identity_len = 0;
488 	struct eap_sim_msg *msg;
489 
490 	data->reauth = 0;
491 	if (id_req == ANY_ID && data->reauth_id) {
492 		identity = data->reauth_id;
493 		identity_len = data->reauth_id_len;
494 		data->reauth = 1;
495 	} else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
496 		   data->pseudonym &&
497 		   !eap_sim_anonymous_username(data->pseudonym,
498 					       data->pseudonym_len)) {
499 		identity = data->pseudonym;
500 		identity_len = data->pseudonym_len;
501 		eap_sim_clear_identities(sm, data, CLEAR_REAUTH_ID);
502 	} else if (id_req != NO_ID_REQ) {
503 		identity = eap_get_config_identity(sm, &identity_len);
504 		if (identity) {
505 			int ids = CLEAR_PSEUDONYM | CLEAR_REAUTH_ID;
506 
507 			if (data->pseudonym &&
508 			    eap_sim_anonymous_username(data->pseudonym,
509 						       data->pseudonym_len))
510 				ids &= ~CLEAR_PSEUDONYM;
511 			eap_sim_clear_identities(sm, data, ids);
512 		}
513 	}
514 	if (id_req != NO_ID_REQ)
515 		eap_sim_clear_identities(sm, data, CLEAR_EAP_ID);
516 
517 	wpa_printf(MSG_DEBUG, "Generating EAP-SIM Start (id=%d)", id);
518 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id,
519 			       EAP_TYPE_SIM, EAP_SIM_SUBTYPE_START);
520 	if (!data->reauth) {
521 		wpa_hexdump(MSG_DEBUG, "   AT_NONCE_MT",
522 			    data->nonce_mt, EAP_SIM_NONCE_MT_LEN);
523 		eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_MT, 0,
524 				data->nonce_mt, EAP_SIM_NONCE_MT_LEN);
525 		wpa_printf(MSG_DEBUG, "   AT_SELECTED_VERSION %d",
526 			   data->selected_version);
527 		eap_sim_msg_add(msg, EAP_SIM_AT_SELECTED_VERSION,
528 				data->selected_version, NULL, 0);
529 	}
530 
531 	if (identity) {
532 		wpa_hexdump_ascii(MSG_DEBUG, "   AT_IDENTITY",
533 				  identity, identity_len);
534 		eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
535 				identity, identity_len);
536 	}
537 
538 	return eap_sim_msg_finish(msg, EAP_TYPE_SIM, NULL, NULL, 0);
539 }
540 
541 
eap_sim_response_challenge(struct eap_sim_data * data,u8 id)542 static struct wpabuf * eap_sim_response_challenge(struct eap_sim_data *data,
543 						  u8 id)
544 {
545 	struct eap_sim_msg *msg;
546 
547 	wpa_printf(MSG_DEBUG, "Generating EAP-SIM Challenge (id=%d)", id);
548 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, EAP_TYPE_SIM,
549 			       EAP_SIM_SUBTYPE_CHALLENGE);
550 	if (data->use_result_ind) {
551 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
552 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
553 	}
554 	wpa_printf(MSG_DEBUG, "   AT_MAC");
555 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
556 	return eap_sim_msg_finish(msg, EAP_TYPE_SIM, data->k_aut,
557 				  (u8 *) data->sres,
558 				  data->num_chal * EAP_SIM_SRES_LEN);
559 }
560 
561 
eap_sim_response_reauth(struct eap_sim_data * data,u8 id,int counter_too_small,const u8 * nonce_s)562 static struct wpabuf * eap_sim_response_reauth(struct eap_sim_data *data,
563 					       u8 id, int counter_too_small,
564 					       const u8 *nonce_s)
565 {
566 	struct eap_sim_msg *msg;
567 	unsigned int counter;
568 
569 	wpa_printf(MSG_DEBUG, "Generating EAP-SIM Reauthentication (id=%d)",
570 		   id);
571 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, EAP_TYPE_SIM,
572 			       EAP_SIM_SUBTYPE_REAUTHENTICATION);
573 	wpa_printf(MSG_DEBUG, "   AT_IV");
574 	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
575 	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
576 
577 	if (counter_too_small) {
578 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER_TOO_SMALL");
579 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
580 		counter = data->counter_too_small;
581 	} else
582 		counter = data->counter;
583 
584 	wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", counter);
585 	eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
586 
587 	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
588 		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt "
589 			   "AT_ENCR_DATA");
590 		eap_sim_msg_free(msg);
591 		return NULL;
592 	}
593 	if (data->use_result_ind) {
594 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
595 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
596 	}
597 	wpa_printf(MSG_DEBUG, "   AT_MAC");
598 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
599 	return eap_sim_msg_finish(msg, EAP_TYPE_SIM, data->k_aut, nonce_s,
600 				  EAP_SIM_NONCE_S_LEN);
601 }
602 
603 
eap_sim_response_notification(struct eap_sim_data * data,u8 id,u16 notification)604 static struct wpabuf * eap_sim_response_notification(struct eap_sim_data *data,
605 						     u8 id, u16 notification)
606 {
607 	struct eap_sim_msg *msg;
608 	u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
609 
610 	wpa_printf(MSG_DEBUG, "Generating EAP-SIM Notification (id=%d)", id);
611 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id,
612 			       EAP_TYPE_SIM, EAP_SIM_SUBTYPE_NOTIFICATION);
613 	if (k_aut && data->reauth) {
614 		wpa_printf(MSG_DEBUG, "   AT_IV");
615 		wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
616 		eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
617 					   EAP_SIM_AT_ENCR_DATA);
618 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", data->counter);
619 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
620 				NULL, 0);
621 		if (eap_sim_msg_add_encr_end(msg, data->k_encr,
622 					     EAP_SIM_AT_PADDING)) {
623 			wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt "
624 				   "AT_ENCR_DATA");
625 			eap_sim_msg_free(msg);
626 			return NULL;
627 		}
628 	}
629 	if (k_aut) {
630 		wpa_printf(MSG_DEBUG, "   AT_MAC");
631 		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
632 	}
633 	return eap_sim_msg_finish(msg, EAP_TYPE_SIM, k_aut, (u8 *) "", 0);
634 }
635 
636 
eap_sim_process_start(struct eap_sm * sm,struct eap_sim_data * data,u8 id,struct eap_sim_attrs * attr)637 static struct wpabuf * eap_sim_process_start(struct eap_sm *sm,
638 					     struct eap_sim_data *data, u8 id,
639 					     struct eap_sim_attrs *attr)
640 {
641 	int selected_version = -1, id_error;
642 	size_t i;
643 	u8 *pos;
644 
645 	wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Start");
646 	if (attr->version_list == NULL) {
647 		wpa_printf(MSG_INFO, "EAP-SIM: No AT_VERSION_LIST in "
648 			   "SIM/Start");
649 		return eap_sim_client_error(data, id,
650 					    EAP_SIM_UNSUPPORTED_VERSION);
651 	}
652 
653 	os_free(data->ver_list);
654 	data->ver_list = os_memdup(attr->version_list, attr->version_list_len);
655 	if (data->ver_list == NULL) {
656 		wpa_printf(MSG_DEBUG, "EAP-SIM: Failed to allocate "
657 			   "memory for version list");
658 		return eap_sim_client_error(data, id,
659 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
660 	}
661 	data->ver_list_len = attr->version_list_len;
662 	pos = data->ver_list;
663 	for (i = 0; i < data->ver_list_len / 2; i++) {
664 		int ver = pos[0] * 256 + pos[1];
665 		pos += 2;
666 		if (eap_sim_supported_ver(ver)) {
667 			selected_version = ver;
668 			break;
669 		}
670 	}
671 	if (selected_version < 0) {
672 		wpa_printf(MSG_INFO, "EAP-SIM: Could not find a supported "
673 			   "version");
674 		return eap_sim_client_error(data, id,
675 					    EAP_SIM_UNSUPPORTED_VERSION);
676 	}
677 	wpa_printf(MSG_DEBUG, "EAP-SIM: Selected Version %d",
678 		   selected_version);
679 	data->selected_version = selected_version;
680 
681 	id_error = 0;
682 	switch (attr->id_req) {
683 	case NO_ID_REQ:
684 		break;
685 	case ANY_ID:
686 		if (data->num_id_req > 0)
687 			id_error++;
688 		data->num_id_req++;
689 		break;
690 	case FULLAUTH_ID:
691 		if (data->num_id_req > 1)
692 			id_error++;
693 		data->num_id_req++;
694 		break;
695 	case PERMANENT_ID:
696 		if (data->num_id_req > 2)
697 			id_error++;
698 		data->num_id_req++;
699 		break;
700 	}
701 	if (id_error) {
702 		wpa_printf(MSG_INFO, "EAP-SIM: Too many ID requests "
703 			   "used within one authentication");
704 		return eap_sim_client_error(data, id,
705 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
706 	}
707 
708 	return eap_sim_response_start(sm, data, id, attr->id_req);
709 }
710 
711 
eap_sim_process_challenge(struct eap_sm * sm,struct eap_sim_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)712 static struct wpabuf * eap_sim_process_challenge(struct eap_sm *sm,
713 						 struct eap_sim_data *data,
714 						 u8 id,
715 						 const struct wpabuf *reqData,
716 						 struct eap_sim_attrs *attr)
717 {
718 	const u8 *identity;
719 	size_t identity_len;
720 	struct eap_sim_attrs eattr;
721 	int res;
722 
723 	wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Challenge");
724 	data->reauth = 0;
725 	if (!attr->mac || !attr->rand) {
726 		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
727 			   "did not include%s%s",
728 			   !attr->mac ? " AT_MAC" : "",
729 			   !attr->rand ? " AT_RAND" : "");
730 		return eap_sim_client_error(data, id,
731 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
732 	}
733 
734 	wpa_printf(MSG_DEBUG, "EAP-SIM: %lu challenges",
735 		   (unsigned long) attr->num_chal);
736 	if (attr->num_chal < data->min_num_chal) {
737 		wpa_printf(MSG_INFO, "EAP-SIM: Insufficient number of "
738 			   "challenges (%lu)", (unsigned long) attr->num_chal);
739 		return eap_sim_client_error(data, id,
740 					    EAP_SIM_INSUFFICIENT_NUM_OF_CHAL);
741 	}
742 	if (attr->num_chal > 3) {
743 		wpa_printf(MSG_INFO, "EAP-SIM: Too many challenges "
744 			   "(%lu)", (unsigned long) attr->num_chal);
745 		return eap_sim_client_error(data, id,
746 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
747 	}
748 
749 	/* Verify that RANDs are different */
750 	if (os_memcmp(attr->rand, attr->rand + GSM_RAND_LEN,
751 		   GSM_RAND_LEN) == 0 ||
752 	    (attr->num_chal > 2 &&
753 	     (os_memcmp(attr->rand, attr->rand + 2 * GSM_RAND_LEN,
754 			GSM_RAND_LEN) == 0 ||
755 	      os_memcmp(attr->rand + GSM_RAND_LEN,
756 			attr->rand + 2 * GSM_RAND_LEN,
757 			GSM_RAND_LEN) == 0))) {
758 		wpa_printf(MSG_INFO, "EAP-SIM: Same RAND used multiple times");
759 		return eap_sim_client_error(data, id,
760 					    EAP_SIM_RAND_NOT_FRESH);
761 	}
762 
763 	os_memcpy(data->rand, attr->rand, attr->num_chal * GSM_RAND_LEN);
764 	data->num_chal = attr->num_chal;
765 
766 	res = eap_sim_gsm_auth(sm, data);
767 	if (res > 0) {
768 		wpa_printf(MSG_DEBUG, "EAP-SIM: Wait for external SIM processing");
769 		return NULL;
770 	}
771 	if (res) {
772 		wpa_printf(MSG_WARNING, "EAP-SIM: GSM authentication failed");
773 		return eap_sim_client_error(data, id,
774 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
775 	}
776 	if (data->last_eap_identity) {
777 		identity = data->last_eap_identity;
778 		identity_len = data->last_eap_identity_len;
779 	} else if (data->pseudonym &&
780 		   !eap_sim_anonymous_username(data->pseudonym,
781 					       data->pseudonym_len)) {
782 		identity = data->pseudonym;
783 		identity_len = data->pseudonym_len;
784 	} else {
785 		struct eap_peer_config *config;
786 
787 		config = eap_get_config(sm);
788 		if (config && config->imsi_identity) {
789 			identity = config->imsi_identity;
790 			identity_len = config->imsi_identity_len;
791 		} else {
792 			identity = eap_get_config_identity(sm, &identity_len);
793 		}
794 	}
795 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Selected identity for MK "
796 			  "derivation", identity, identity_len);
797 	eap_sim_derive_mk(identity, identity_len, data->nonce_mt,
798 			  data->selected_version, data->ver_list,
799 			  data->ver_list_len, data->num_chal,
800 			  (const u8 *) data->kc, data->mk);
801 	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
802 			    data->emsk);
803 	if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, data->nonce_mt,
804 			       EAP_SIM_NONCE_MT_LEN)) {
805 		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
806 			   "used invalid AT_MAC");
807 #ifdef TEST_FUZZ
808 		wpa_printf(MSG_INFO,
809 			   "TEST: Ignore AT_MAC mismatch for fuzz testing");
810 #else /* TEST_FUZZ */
811 		return eap_sim_client_error(data, id,
812 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
813 #endif /* TEST_FUZZ */
814 	}
815 
816 	/* Old reauthentication identity must not be used anymore. In
817 	 * other words, if no new reauth identity is received, full
818 	 * authentication will be used on next reauthentication (using
819 	 * pseudonym identity or permanent identity). */
820 	eap_sim_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
821 
822 	if (attr->encr_data) {
823 		u8 *decrypted;
824 		decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
825 					       attr->encr_data_len, attr->iv,
826 					       &eattr, 0);
827 		if (decrypted == NULL) {
828 			return eap_sim_client_error(
829 				data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET);
830 		}
831 		eap_sim_learn_ids(sm, data, &eattr);
832 		os_free(decrypted);
833 	}
834 
835 	if (data->result_ind && attr->result_ind)
836 		data->use_result_ind = 1;
837 
838 	if (data->state != FAILURE) {
839 		eap_sim_state(data, data->use_result_ind ?
840 			      RESULT_SUCCESS : SUCCESS);
841 	}
842 
843 	data->num_id_req = 0;
844 	data->num_notification = 0;
845 	/* RFC 4186 specifies that counter is initialized to one after
846 	 * fullauth, but initializing it to zero makes it easier to implement
847 	 * reauth verification. */
848 	data->counter = 0;
849 	return eap_sim_response_challenge(data, id);
850 }
851 
852 
eap_sim_process_notification_reauth(struct eap_sim_data * data,struct eap_sim_attrs * attr)853 static int eap_sim_process_notification_reauth(struct eap_sim_data *data,
854 					       struct eap_sim_attrs *attr)
855 {
856 	struct eap_sim_attrs eattr;
857 	u8 *decrypted;
858 
859 	if (attr->encr_data == NULL || attr->iv == NULL) {
860 		wpa_printf(MSG_WARNING, "EAP-SIM: Notification message after "
861 			   "reauth did not include encrypted data");
862 		return -1;
863 	}
864 
865 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
866 				       attr->encr_data_len, attr->iv, &eattr,
867 				       0);
868 	if (decrypted == NULL) {
869 		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted "
870 			   "data from notification message");
871 		return -1;
872 	}
873 
874 	if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
875 		wpa_printf(MSG_WARNING, "EAP-SIM: Counter in notification "
876 			   "message does not match with counter in reauth "
877 			   "message");
878 		os_free(decrypted);
879 		return -1;
880 	}
881 
882 	os_free(decrypted);
883 	return 0;
884 }
885 
886 
eap_sim_process_notification_auth(struct eap_sim_data * data,const struct wpabuf * reqData,struct eap_sim_attrs * attr)887 static int eap_sim_process_notification_auth(struct eap_sim_data *data,
888 					     const struct wpabuf *reqData,
889 					     struct eap_sim_attrs *attr)
890 {
891 	if (attr->mac == NULL) {
892 		wpa_printf(MSG_INFO, "EAP-SIM: no AT_MAC in after_auth "
893 			   "Notification message");
894 		return -1;
895 	}
896 
897 	if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, (u8 *) "", 0))
898 	{
899 		wpa_printf(MSG_WARNING, "EAP-SIM: Notification message "
900 			   "used invalid AT_MAC");
901 		return -1;
902 	}
903 
904 	if (data->reauth &&
905 	    eap_sim_process_notification_reauth(data, attr)) {
906 		wpa_printf(MSG_WARNING, "EAP-SIM: Invalid notification "
907 			   "message after reauth");
908 		return -1;
909 	}
910 
911 	return 0;
912 }
913 
914 
eap_sim_process_notification(struct eap_sm * sm,struct eap_sim_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)915 static struct wpabuf * eap_sim_process_notification(
916 	struct eap_sm *sm, struct eap_sim_data *data, u8 id,
917 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
918 {
919 	wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Notification");
920 	if (data->num_notification > 0) {
921 		wpa_printf(MSG_INFO, "EAP-SIM: too many notification "
922 			   "rounds (only one allowed)");
923 		return eap_sim_client_error(data, id,
924 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
925 	}
926 	data->num_notification++;
927 	if (attr->notification == -1) {
928 		wpa_printf(MSG_INFO, "EAP-SIM: no AT_NOTIFICATION in "
929 			   "Notification message");
930 		return eap_sim_client_error(data, id,
931 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
932 	}
933 
934 	if ((attr->notification & 0x4000) == 0 &&
935 	    eap_sim_process_notification_auth(data, reqData, attr)) {
936 		return eap_sim_client_error(data, id,
937 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
938 	}
939 
940 	eap_sim_report_notification(sm->msg_ctx, attr->notification, 0);
941 	if (attr->notification >= 0 && attr->notification < 32768) {
942 		data->error_code = attr->notification;
943 		eap_sim_state(data, FAILURE);
944 	} else if (attr->notification == EAP_SIM_SUCCESS &&
945 		   data->state == RESULT_SUCCESS)
946 		eap_sim_state(data, SUCCESS);
947 	return eap_sim_response_notification(data, id, attr->notification);
948 }
949 
950 
eap_sim_process_reauthentication(struct eap_sm * sm,struct eap_sim_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)951 static struct wpabuf * eap_sim_process_reauthentication(
952 	struct eap_sm *sm, struct eap_sim_data *data, u8 id,
953 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
954 {
955 	struct eap_sim_attrs eattr;
956 	u8 *decrypted;
957 
958 	wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Reauthentication");
959 
960 	if (data->reauth_id == NULL) {
961 		wpa_printf(MSG_WARNING, "EAP-SIM: Server is trying "
962 			   "reauthentication, but no reauth_id available");
963 		return eap_sim_client_error(data, id,
964 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
965 	}
966 
967 	data->reauth = 1;
968 	if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, (u8 *) "", 0))
969 	{
970 		wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication "
971 			   "did not have valid AT_MAC");
972 #ifdef TEST_FUZZ
973 		wpa_printf(MSG_INFO,
974 			   "TEST: Ignore AT_MAC mismatch for fuzz testing");
975 #else /* TEST_FUZZ */
976 		return eap_sim_client_error(data, id,
977 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
978 #endif /* TEST_FUZZ */
979 	}
980 
981 	/* At this stage the received MAC has been verified. Use this MAC for
982 	 * reauth Session-Id calculation if all other checks pass.
983 	 * The peer does not use the local MAC but the received MAC in deriving
984 	 * Session-Id. */
985 #ifdef TEST_FUZZ
986 	if (attr->mac)
987 		os_memcpy(data->reauth_mac, attr->mac, EAP_SIM_MAC_LEN);
988 	else
989 		os_memset(data->reauth_mac, 0x12, EAP_SIM_MAC_LEN);
990 #else /* TEST_FUZZ */
991 	os_memcpy(data->reauth_mac, attr->mac, EAP_SIM_MAC_LEN);
992 #endif /* TEST_FUZZ */
993 	wpa_hexdump(MSG_DEBUG, "EAP-SIM: Server MAC",
994 		    data->reauth_mac, EAP_SIM_MAC_LEN);
995 
996 	if (attr->encr_data == NULL || attr->iv == NULL) {
997 		wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication "
998 			   "message did not include encrypted data");
999 		return eap_sim_client_error(data, id,
1000 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
1001 	}
1002 
1003 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1004 				       attr->encr_data_len, attr->iv, &eattr,
1005 				       0);
1006 	if (decrypted == NULL) {
1007 		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted "
1008 			   "data from reauthentication message");
1009 		return eap_sim_client_error(data, id,
1010 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
1011 	}
1012 
1013 	if (eattr.nonce_s == NULL || eattr.counter < 0) {
1014 		wpa_printf(MSG_INFO, "EAP-SIM: (encr) No%s%s in reauth packet",
1015 			   !eattr.nonce_s ? " AT_NONCE_S" : "",
1016 			   eattr.counter < 0 ? " AT_COUNTER" : "");
1017 		os_free(decrypted);
1018 		return eap_sim_client_error(data, id,
1019 					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
1020 	}
1021 
1022 	if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1023 		struct wpabuf *res;
1024 		wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid counter "
1025 			   "(%d <= %d)", eattr.counter, data->counter);
1026 		data->counter_too_small = eattr.counter;
1027 
1028 		/* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1029 		 * reauth_id must not be used to start a new reauthentication.
1030 		 * However, since it was used in the last EAP-Response-Identity
1031 		 * packet, it has to saved for the following fullauth to be
1032 		 * used in MK derivation. */
1033 		os_free(data->last_eap_identity);
1034 		data->last_eap_identity = data->reauth_id;
1035 		data->last_eap_identity_len = data->reauth_id_len;
1036 		data->reauth_id = NULL;
1037 		data->reauth_id_len = 0;
1038 
1039 		res = eap_sim_response_reauth(data, id, 1, eattr.nonce_s);
1040 		os_free(decrypted);
1041 
1042 		return res;
1043 	}
1044 	data->counter = eattr.counter;
1045 
1046 	os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1047 	wpa_hexdump(MSG_DEBUG, "EAP-SIM: (encr) AT_NONCE_S",
1048 		    data->nonce_s, EAP_SIM_NONCE_S_LEN);
1049 
1050 	eap_sim_derive_keys_reauth(data->counter,
1051 				   data->reauth_id, data->reauth_id_len,
1052 				   data->nonce_s, data->mk, data->msk,
1053 				   data->emsk);
1054 	eap_sim_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1055 	eap_sim_learn_ids(sm, data, &eattr);
1056 
1057 	if (data->result_ind && attr->result_ind)
1058 		data->use_result_ind = 1;
1059 
1060 	if (data->state != FAILURE) {
1061 		eap_sim_state(data, data->use_result_ind ?
1062 			      RESULT_SUCCESS : SUCCESS);
1063 	}
1064 
1065 	data->num_id_req = 0;
1066 	data->num_notification = 0;
1067 	if (data->counter > EAP_SIM_MAX_FAST_REAUTHS) {
1068 		wpa_printf(MSG_DEBUG, "EAP-SIM: Maximum number of "
1069 			   "fast reauths performed - force fullauth");
1070 		eap_sim_clear_identities(sm, data,
1071 					 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1072 	}
1073 	os_free(decrypted);
1074 	return eap_sim_response_reauth(data, id, 0, data->nonce_s);
1075 }
1076 
1077 
eap_sim_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)1078 static struct wpabuf * eap_sim_process(struct eap_sm *sm, void *priv,
1079 				       struct eap_method_ret *ret,
1080 				       const struct wpabuf *reqData)
1081 {
1082 	struct eap_sim_data *data = priv;
1083 	const struct eap_hdr *req;
1084 	u8 subtype, id;
1085 	struct wpabuf *res;
1086 	const u8 *pos;
1087 	struct eap_sim_attrs attr;
1088 	size_t len;
1089 
1090 	wpa_hexdump_buf(MSG_DEBUG, "EAP-SIM: EAP data", reqData);
1091 	if (eap_get_config_identity(sm, &len) == NULL) {
1092 		wpa_printf(MSG_INFO, "EAP-SIM: Identity not configured");
1093 		eap_sm_request_identity(sm);
1094 		ret->ignore = TRUE;
1095 		return NULL;
1096 	}
1097 
1098 	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, reqData, &len);
1099 	if (pos == NULL || len < 3) {
1100 		ret->ignore = TRUE;
1101 		return NULL;
1102 	}
1103 	req = wpabuf_head(reqData);
1104 	id = req->identifier;
1105 	len = be_to_host16(req->length);
1106 
1107 	ret->ignore = FALSE;
1108 	ret->methodState = METHOD_MAY_CONT;
1109 	ret->decision = DECISION_FAIL;
1110 	ret->allowNotifications = TRUE;
1111 
1112 	subtype = *pos++;
1113 	wpa_printf(MSG_DEBUG, "EAP-SIM: Subtype=%d", subtype);
1114 	pos += 2; /* Reserved */
1115 
1116 	if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr, 0,
1117 			       0)) {
1118 		res = eap_sim_client_error(data, id,
1119 					   EAP_SIM_UNABLE_TO_PROCESS_PACKET);
1120 		goto done;
1121 	}
1122 
1123 	switch (subtype) {
1124 	case EAP_SIM_SUBTYPE_START:
1125 		res = eap_sim_process_start(sm, data, id, &attr);
1126 		break;
1127 	case EAP_SIM_SUBTYPE_CHALLENGE:
1128 		res = eap_sim_process_challenge(sm, data, id, reqData, &attr);
1129 		break;
1130 	case EAP_SIM_SUBTYPE_NOTIFICATION:
1131 		res = eap_sim_process_notification(sm, data, id, reqData,
1132 						   &attr);
1133 		break;
1134 	case EAP_SIM_SUBTYPE_REAUTHENTICATION:
1135 		res = eap_sim_process_reauthentication(sm, data, id, reqData,
1136 						       &attr);
1137 		break;
1138 	case EAP_SIM_SUBTYPE_CLIENT_ERROR:
1139 		wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Client-Error");
1140 		res = eap_sim_client_error(data, id,
1141 					   EAP_SIM_UNABLE_TO_PROCESS_PACKET);
1142 		break;
1143 	default:
1144 		wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown subtype=%d", subtype);
1145 		res = eap_sim_client_error(data, id,
1146 					   EAP_SIM_UNABLE_TO_PROCESS_PACKET);
1147 		break;
1148 	}
1149 
1150 done:
1151 	if (data->state == FAILURE) {
1152 		ret->decision = DECISION_FAIL;
1153 		ret->methodState = METHOD_DONE;
1154 	} else if (data->state == SUCCESS) {
1155 		ret->decision = data->use_result_ind ?
1156 			DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1157 		ret->methodState = data->use_result_ind ?
1158 			METHOD_DONE : METHOD_MAY_CONT;
1159 	} else if (data->state == RESULT_SUCCESS)
1160 		ret->methodState = METHOD_CONT;
1161 
1162 	if (ret->methodState == METHOD_DONE) {
1163 		ret->allowNotifications = FALSE;
1164 	}
1165 
1166 	return res;
1167 }
1168 
1169 
eap_sim_has_reauth_data(struct eap_sm * sm,void * priv)1170 static Boolean eap_sim_has_reauth_data(struct eap_sm *sm, void *priv)
1171 {
1172 	struct eap_sim_data *data = priv;
1173 	return data->pseudonym || data->reauth_id;
1174 }
1175 
1176 
eap_sim_deinit_for_reauth(struct eap_sm * sm,void * priv)1177 static void eap_sim_deinit_for_reauth(struct eap_sm *sm, void *priv)
1178 {
1179 	struct eap_sim_data *data = priv;
1180 	eap_sim_clear_identities(sm, data, CLEAR_EAP_ID);
1181 	data->use_result_ind = 0;
1182 	eap_sim_clear_keys(data, 1);
1183 }
1184 
1185 
eap_sim_init_for_reauth(struct eap_sm * sm,void * priv)1186 static void * eap_sim_init_for_reauth(struct eap_sm *sm, void *priv)
1187 {
1188 	struct eap_sim_data *data = priv;
1189 	if (random_get_bytes(data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) {
1190 		wpa_printf(MSG_WARNING, "EAP-SIM: Failed to get random data "
1191 			   "for NONCE_MT");
1192 		eap_sim_deinit(sm, data);
1193 		return NULL;
1194 	}
1195 	data->num_id_req = 0;
1196 	data->num_notification = 0;
1197 	eap_sim_state(data, CONTINUE);
1198 	return priv;
1199 }
1200 
1201 
eap_sim_get_identity(struct eap_sm * sm,void * priv,size_t * len)1202 static const u8 * eap_sim_get_identity(struct eap_sm *sm, void *priv,
1203 				       size_t *len)
1204 {
1205 	struct eap_sim_data *data = priv;
1206 
1207 	if (data->reauth_id) {
1208 		*len = data->reauth_id_len;
1209 		return data->reauth_id;
1210 	}
1211 
1212 	if (data->pseudonym) {
1213 		*len = data->pseudonym_len;
1214 		return data->pseudonym;
1215 	}
1216 
1217 	return NULL;
1218 }
1219 
1220 
eap_sim_isKeyAvailable(struct eap_sm * sm,void * priv)1221 static Boolean eap_sim_isKeyAvailable(struct eap_sm *sm, void *priv)
1222 {
1223 	struct eap_sim_data *data = priv;
1224 	return data->state == SUCCESS;
1225 }
1226 
1227 
eap_sim_getKey(struct eap_sm * sm,void * priv,size_t * len)1228 static u8 * eap_sim_getKey(struct eap_sm *sm, void *priv, size_t *len)
1229 {
1230 	struct eap_sim_data *data = priv;
1231 	u8 *key;
1232 
1233 	if (data->state != SUCCESS)
1234 		return NULL;
1235 
1236 	key = os_memdup(data->msk, EAP_SIM_KEYING_DATA_LEN);
1237 	if (key == NULL)
1238 		return NULL;
1239 
1240 	*len = EAP_SIM_KEYING_DATA_LEN;
1241 
1242 	return key;
1243 }
1244 
1245 
eap_sim_get_session_id(struct eap_sm * sm,void * priv,size_t * len)1246 static u8 * eap_sim_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1247 {
1248 	struct eap_sim_data *data = priv;
1249 	u8 *id;
1250 
1251 	if (data->state != SUCCESS)
1252 		return NULL;
1253 
1254 	if (!data->reauth)
1255 		*len = 1 + data->num_chal * GSM_RAND_LEN + EAP_SIM_NONCE_MT_LEN;
1256 	else
1257 		*len = 1 + EAP_SIM_NONCE_S_LEN + EAP_SIM_MAC_LEN;
1258 	id = os_malloc(*len);
1259 	if (id == NULL)
1260 		return NULL;
1261 
1262 	id[0] = EAP_TYPE_SIM;
1263 	if (!data->reauth) {
1264 		os_memcpy(id + 1, data->rand, data->num_chal * GSM_RAND_LEN);
1265 		os_memcpy(id + 1 + data->num_chal * GSM_RAND_LEN,
1266 			  data->nonce_mt, EAP_SIM_NONCE_MT_LEN);
1267 	} else {
1268 		os_memcpy(id + 1, data->nonce_s, EAP_SIM_NONCE_S_LEN);
1269 		os_memcpy(id + 1 + EAP_SIM_NONCE_S_LEN, data->reauth_mac,
1270 			  EAP_SIM_MAC_LEN);
1271 	}
1272 	wpa_hexdump(MSG_DEBUG, "EAP-SIM: Derived Session-Id", id, *len);
1273 
1274 	return id;
1275 }
1276 
1277 
eap_sim_get_emsk(struct eap_sm * sm,void * priv,size_t * len)1278 static u8 * eap_sim_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1279 {
1280 	struct eap_sim_data *data = priv;
1281 	u8 *key;
1282 
1283 	if (data->state != SUCCESS)
1284 		return NULL;
1285 
1286 	key = os_memdup(data->emsk, EAP_EMSK_LEN);
1287 	if (key == NULL)
1288 		return NULL;
1289 
1290 	*len = EAP_EMSK_LEN;
1291 
1292 	return key;
1293 }
1294 
1295 
eap_sim_get_error_code(void * priv)1296 static int eap_sim_get_error_code(void *priv)
1297 {
1298 	struct eap_sim_data *data = priv;
1299 	int current_data_error;
1300 
1301 	if (!data)
1302 		return NO_EAP_METHOD_ERROR;
1303 
1304 	current_data_error = data->error_code;
1305 
1306 	/* Now reset for next transaction */
1307 	data->error_code = NO_EAP_METHOD_ERROR;
1308 
1309 	return current_data_error;
1310 }
1311 
1312 
eap_peer_sim_register(void)1313 int eap_peer_sim_register(void)
1314 {
1315 	struct eap_method *eap;
1316 
1317 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1318 				    EAP_VENDOR_IETF, EAP_TYPE_SIM, "SIM");
1319 	if (eap == NULL)
1320 		return -1;
1321 
1322 	eap->init = eap_sim_init;
1323 	eap->deinit = eap_sim_deinit;
1324 	eap->process = eap_sim_process;
1325 	eap->isKeyAvailable = eap_sim_isKeyAvailable;
1326 	eap->getKey = eap_sim_getKey;
1327 	eap->getSessionId = eap_sim_get_session_id;
1328 	eap->has_reauth_data = eap_sim_has_reauth_data;
1329 	eap->deinit_for_reauth = eap_sim_deinit_for_reauth;
1330 	eap->init_for_reauth = eap_sim_init_for_reauth;
1331 	eap->get_identity = eap_sim_get_identity;
1332 	eap->get_emsk = eap_sim_get_emsk;
1333 	eap->get_error_code = eap_sim_get_error_code;
1334 
1335 	return eap_peer_method_register(eap);
1336 }
1337