1 /*
2  * EAP peer method: EAP-TLS (RFC 2716)
3  * Copyright (c) 2004-2008, 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 "crypto/tls.h"
13 #include "eap_i.h"
14 #include "eap_tls_common.h"
15 #include "eap_config.h"
16 
17 
18 static void eap_tls_deinit(struct eap_sm *sm, void *priv);
19 
20 
21 struct eap_tls_data {
22 	struct eap_ssl_data ssl;
23 	u8 *key_data;
24 	u8 *session_id;
25 	size_t id_len;
26 	void *ssl_ctx;
27 	u8 eap_type;
28 };
29 
30 
eap_tls_init(struct eap_sm * sm)31 static void * eap_tls_init(struct eap_sm *sm)
32 {
33 	struct eap_tls_data *data;
34 	struct eap_peer_config *config = eap_get_config(sm);
35 	if (config == NULL ||
36 	    ((sm->init_phase2 ? config->private_key2 : config->private_key)
37 	     == NULL &&
38 	     (sm->init_phase2 ? config->engine2 : config->engine) == 0)) {
39 		wpa_printf(MSG_INFO, "EAP-TLS: Private key not configured");
40 		return NULL;
41 	}
42 
43 	data = os_zalloc(sizeof(*data));
44 	if (data == NULL)
45 		return NULL;
46 
47 	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
48 		sm->ssl_ctx;
49 
50 	if (eap_peer_tls_ssl_init(sm, &data->ssl, config, EAP_TYPE_TLS)) {
51 		wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
52 		eap_tls_deinit(sm, data);
53 		if (config->engine) {
54 			wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting Smartcard "
55 				   "PIN");
56 			eap_sm_request_pin(sm);
57 			sm->ignore = TRUE;
58 		} else if (config->private_key && !config->private_key_passwd)
59 		{
60 			wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting private "
61 				   "key passphrase");
62 			eap_sm_request_passphrase(sm);
63 			sm->ignore = TRUE;
64 		}
65 		return NULL;
66 	}
67 
68 	data->eap_type = EAP_TYPE_TLS;
69 
70 	return data;
71 }
72 
73 
74 #ifdef EAP_UNAUTH_TLS
eap_unauth_tls_init(struct eap_sm * sm)75 static void * eap_unauth_tls_init(struct eap_sm *sm)
76 {
77 	struct eap_tls_data *data;
78 	struct eap_peer_config *config = eap_get_config(sm);
79 
80 	data = os_zalloc(sizeof(*data));
81 	if (data == NULL)
82 		return NULL;
83 
84 	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
85 		sm->ssl_ctx;
86 
87 	if (eap_peer_tls_ssl_init(sm, &data->ssl, config,
88 				  EAP_UNAUTH_TLS_TYPE)) {
89 		wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
90 		eap_tls_deinit(sm, data);
91 		return NULL;
92 	}
93 
94 	data->eap_type = EAP_UNAUTH_TLS_TYPE;
95 
96 	return data;
97 }
98 #endif /* EAP_UNAUTH_TLS */
99 
100 
101 #ifdef CONFIG_HS20
eap_wfa_unauth_tls_init(struct eap_sm * sm)102 static void * eap_wfa_unauth_tls_init(struct eap_sm *sm)
103 {
104 	struct eap_tls_data *data;
105 	struct eap_peer_config *config = eap_get_config(sm);
106 
107 	data = os_zalloc(sizeof(*data));
108 	if (data == NULL)
109 		return NULL;
110 
111 	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
112 		sm->ssl_ctx;
113 
114 	if (eap_peer_tls_ssl_init(sm, &data->ssl, config,
115 				  EAP_WFA_UNAUTH_TLS_TYPE)) {
116 		wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
117 		eap_tls_deinit(sm, data);
118 		return NULL;
119 	}
120 
121 	data->eap_type = EAP_WFA_UNAUTH_TLS_TYPE;
122 
123 	return data;
124 }
125 #endif /* CONFIG_HS20 */
126 
127 
eap_tls_free_key(struct eap_tls_data * data)128 static void eap_tls_free_key(struct eap_tls_data *data)
129 {
130 	if (data->key_data) {
131 		bin_clear_free(data->key_data, EAP_TLS_KEY_LEN + EAP_EMSK_LEN);
132 		data->key_data = NULL;
133 	}
134 }
135 
136 
eap_tls_deinit(struct eap_sm * sm,void * priv)137 static void eap_tls_deinit(struct eap_sm *sm, void *priv)
138 {
139 	struct eap_tls_data *data = priv;
140 	if (data == NULL)
141 		return;
142 	eap_peer_tls_ssl_deinit(sm, &data->ssl);
143 	eap_tls_free_key(data);
144 	os_free(data->session_id);
145 	os_free(data);
146 }
147 
148 
eap_tls_failure(struct eap_sm * sm,struct eap_tls_data * data,struct eap_method_ret * ret,int res,struct wpabuf * resp,u8 id)149 static struct wpabuf * eap_tls_failure(struct eap_sm *sm,
150 				       struct eap_tls_data *data,
151 				       struct eap_method_ret *ret, int res,
152 				       struct wpabuf *resp, u8 id)
153 {
154 	wpa_printf(MSG_DEBUG, "EAP-TLS: TLS processing failed");
155 
156 	ret->methodState = METHOD_DONE;
157 	ret->decision = DECISION_FAIL;
158 
159 	if (res == -1) {
160 		struct eap_peer_config *config = eap_get_config(sm);
161 		if (config) {
162 			/*
163 			 * The TLS handshake failed. So better forget the old
164 			 * PIN. It may be wrong, we cannot be sure but trying
165 			 * the wrong one again might block it on the card--so
166 			 * better ask the user again.
167 			 */
168 			os_free(config->pin);
169 			config->pin = NULL;
170 		}
171 	}
172 
173 	if (resp) {
174 		/*
175 		 * This is likely an alert message, so send it instead of just
176 		 * ACKing the error.
177 		 */
178 		return resp;
179 	}
180 
181 	return eap_peer_tls_build_ack(id, data->eap_type, 0);
182 }
183 
184 
eap_tls_success(struct eap_sm * sm,struct eap_tls_data * data,struct eap_method_ret * ret)185 static void eap_tls_success(struct eap_sm *sm, struct eap_tls_data *data,
186 			    struct eap_method_ret *ret)
187 {
188 	wpa_printf(MSG_DEBUG, "EAP-TLS: Done");
189 
190 	ret->methodState = METHOD_DONE;
191 	ret->decision = DECISION_UNCOND_SUCC;
192 
193 	eap_tls_free_key(data);
194 	data->key_data = eap_peer_tls_derive_key(sm, &data->ssl,
195 						 "client EAP encryption",
196 						 EAP_TLS_KEY_LEN +
197 						 EAP_EMSK_LEN);
198 	if (data->key_data) {
199 		wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived key",
200 				data->key_data, EAP_TLS_KEY_LEN);
201 		wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived EMSK",
202 				data->key_data + EAP_TLS_KEY_LEN,
203 				EAP_EMSK_LEN);
204 	} else {
205 		wpa_printf(MSG_INFO, "EAP-TLS: Failed to derive key");
206 	}
207 
208 	os_free(data->session_id);
209 	data->session_id = eap_peer_tls_derive_session_id(sm, &data->ssl,
210 							  EAP_TYPE_TLS,
211 			                                  &data->id_len);
212 	if (data->session_id) {
213 		wpa_hexdump(MSG_DEBUG, "EAP-TLS: Derived Session-Id",
214 			    data->session_id, data->id_len);
215 	} else {
216 		wpa_printf(MSG_ERROR, "EAP-TLS: Failed to derive Session-Id");
217 	}
218 }
219 
220 
eap_tls_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)221 static struct wpabuf * eap_tls_process(struct eap_sm *sm, void *priv,
222 				       struct eap_method_ret *ret,
223 				       const struct wpabuf *reqData)
224 {
225 	size_t left;
226 	int res;
227 	struct wpabuf *resp;
228 	u8 flags, id;
229 	const u8 *pos;
230 	struct eap_tls_data *data = priv;
231 	struct wpabuf msg;
232 
233 	pos = eap_peer_tls_process_init(sm, &data->ssl, data->eap_type, ret,
234 					reqData, &left, &flags);
235 	if (pos == NULL)
236 		return NULL;
237 	id = eap_get_id(reqData);
238 
239 	if (flags & EAP_TLS_FLAGS_START) {
240 		wpa_printf(MSG_DEBUG, "EAP-TLS: Start");
241 		left = 0; /* make sure that this frame is empty, even though it
242 			   * should always be, anyway */
243 	}
244 
245 	resp = NULL;
246 	wpabuf_set(&msg, pos, left);
247 	res = eap_peer_tls_process_helper(sm, &data->ssl, data->eap_type, 0,
248 					  id, &msg, &resp);
249 
250 	if (res < 0) {
251 		return eap_tls_failure(sm, data, ret, res, resp, id);
252 	}
253 
254 	if (tls_connection_established(data->ssl_ctx, data->ssl.conn))
255 		eap_tls_success(sm, data, ret);
256 
257 	if (res == 1) {
258 		wpabuf_free(resp);
259 		return eap_peer_tls_build_ack(id, data->eap_type, 0);
260 	}
261 
262 	return resp;
263 }
264 
265 
eap_tls_has_reauth_data(struct eap_sm * sm,void * priv)266 static Boolean eap_tls_has_reauth_data(struct eap_sm *sm, void *priv)
267 {
268 	struct eap_tls_data *data = priv;
269 	return tls_connection_established(data->ssl_ctx, data->ssl.conn);
270 }
271 
272 
eap_tls_deinit_for_reauth(struct eap_sm * sm,void * priv)273 static void eap_tls_deinit_for_reauth(struct eap_sm *sm, void *priv)
274 {
275 }
276 
277 
eap_tls_init_for_reauth(struct eap_sm * sm,void * priv)278 static void * eap_tls_init_for_reauth(struct eap_sm *sm, void *priv)
279 {
280 	struct eap_tls_data *data = priv;
281 	eap_tls_free_key(data);
282 	os_free(data->session_id);
283 	data->session_id = NULL;
284 	if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
285 		os_free(data);
286 		return NULL;
287 	}
288 	return priv;
289 }
290 
291 
eap_tls_get_status(struct eap_sm * sm,void * priv,char * buf,size_t buflen,int verbose)292 static int eap_tls_get_status(struct eap_sm *sm, void *priv, char *buf,
293 			      size_t buflen, int verbose)
294 {
295 	struct eap_tls_data *data = priv;
296 	return eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
297 }
298 
299 
eap_tls_isKeyAvailable(struct eap_sm * sm,void * priv)300 static Boolean eap_tls_isKeyAvailable(struct eap_sm *sm, void *priv)
301 {
302 	struct eap_tls_data *data = priv;
303 	return data->key_data != NULL;
304 }
305 
306 
eap_tls_getKey(struct eap_sm * sm,void * priv,size_t * len)307 static u8 * eap_tls_getKey(struct eap_sm *sm, void *priv, size_t *len)
308 {
309 	struct eap_tls_data *data = priv;
310 	u8 *key;
311 
312 	if (data->key_data == NULL)
313 		return NULL;
314 
315 	key = os_malloc(EAP_TLS_KEY_LEN);
316 	if (key == NULL)
317 		return NULL;
318 
319 	*len = EAP_TLS_KEY_LEN;
320 	os_memcpy(key, data->key_data, EAP_TLS_KEY_LEN);
321 
322 	return key;
323 }
324 
325 
eap_tls_get_emsk(struct eap_sm * sm,void * priv,size_t * len)326 static u8 * eap_tls_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
327 {
328 	struct eap_tls_data *data = priv;
329 	u8 *key;
330 
331 	if (data->key_data == NULL)
332 		return NULL;
333 
334 	key = os_malloc(EAP_EMSK_LEN);
335 	if (key == NULL)
336 		return NULL;
337 
338 	*len = EAP_EMSK_LEN;
339 	os_memcpy(key, data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
340 
341 	return key;
342 }
343 
344 
eap_tls_get_session_id(struct eap_sm * sm,void * priv,size_t * len)345 static u8 * eap_tls_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
346 {
347 	struct eap_tls_data *data = priv;
348 	u8 *id;
349 
350 	if (data->session_id == NULL)
351 		return NULL;
352 
353 	id = os_malloc(data->id_len);
354 	if (id == NULL)
355 		return NULL;
356 
357 	*len = data->id_len;
358 	os_memcpy(id, data->session_id, data->id_len);
359 
360 	return id;
361 }
362 
363 
eap_peer_tls_register(void)364 int eap_peer_tls_register(void)
365 {
366 	struct eap_method *eap;
367 	int ret;
368 
369 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
370 				    EAP_VENDOR_IETF, EAP_TYPE_TLS, "TLS");
371 	if (eap == NULL)
372 		return -1;
373 
374 	eap->init = eap_tls_init;
375 	eap->deinit = eap_tls_deinit;
376 	eap->process = eap_tls_process;
377 	eap->isKeyAvailable = eap_tls_isKeyAvailable;
378 	eap->getKey = eap_tls_getKey;
379 	eap->getSessionId = eap_tls_get_session_id;
380 	eap->get_status = eap_tls_get_status;
381 	eap->has_reauth_data = eap_tls_has_reauth_data;
382 	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
383 	eap->init_for_reauth = eap_tls_init_for_reauth;
384 	eap->get_emsk = eap_tls_get_emsk;
385 
386 	ret = eap_peer_method_register(eap);
387 	if (ret)
388 		eap_peer_method_free(eap);
389 	return ret;
390 }
391 
392 
393 #ifdef EAP_UNAUTH_TLS
eap_peer_unauth_tls_register(void)394 int eap_peer_unauth_tls_register(void)
395 {
396 	struct eap_method *eap;
397 	int ret;
398 
399 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
400 				    EAP_VENDOR_UNAUTH_TLS,
401 				    EAP_VENDOR_TYPE_UNAUTH_TLS, "UNAUTH-TLS");
402 	if (eap == NULL)
403 		return -1;
404 
405 	eap->init = eap_unauth_tls_init;
406 	eap->deinit = eap_tls_deinit;
407 	eap->process = eap_tls_process;
408 	eap->isKeyAvailable = eap_tls_isKeyAvailable;
409 	eap->getKey = eap_tls_getKey;
410 	eap->get_status = eap_tls_get_status;
411 	eap->has_reauth_data = eap_tls_has_reauth_data;
412 	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
413 	eap->init_for_reauth = eap_tls_init_for_reauth;
414 	eap->get_emsk = eap_tls_get_emsk;
415 
416 	ret = eap_peer_method_register(eap);
417 	if (ret)
418 		eap_peer_method_free(eap);
419 	return ret;
420 }
421 #endif /* EAP_UNAUTH_TLS */
422 
423 
424 #ifdef CONFIG_HS20
eap_peer_wfa_unauth_tls_register(void)425 int eap_peer_wfa_unauth_tls_register(void)
426 {
427 	struct eap_method *eap;
428 	int ret;
429 
430 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
431 				    EAP_VENDOR_WFA_NEW,
432 				    EAP_VENDOR_WFA_UNAUTH_TLS,
433 				    "WFA-UNAUTH-TLS");
434 	if (eap == NULL)
435 		return -1;
436 
437 	eap->init = eap_wfa_unauth_tls_init;
438 	eap->deinit = eap_tls_deinit;
439 	eap->process = eap_tls_process;
440 	eap->isKeyAvailable = eap_tls_isKeyAvailable;
441 	eap->getKey = eap_tls_getKey;
442 	eap->get_status = eap_tls_get_status;
443 	eap->has_reauth_data = eap_tls_has_reauth_data;
444 	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
445 	eap->init_for_reauth = eap_tls_init_for_reauth;
446 	eap->get_emsk = eap_tls_get_emsk;
447 
448 	ret = eap_peer_method_register(eap);
449 	if (ret)
450 		eap_peer_method_free(eap);
451 	return ret;
452 }
453 #endif /* CONFIG_HS20 */
454