1/*
2 * EAP peer method: EAP-TLS (RFC 2716)
3 * Copyright (c) 2004-2008, 2012-2015, 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
18static void eap_tls_deinit(struct eap_sm *sm, void *priv);
19
20
21struct 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	struct wpabuf *pending_resp;
29};
30
31
32static void * eap_tls_init(struct eap_sm *sm)
33{
34	struct eap_tls_data *data;
35	struct eap_peer_config *config = eap_get_config(sm);
36	if (config == NULL ||
37	    ((sm->init_phase2 ? config->private_key2 : config->private_key)
38	     == NULL &&
39	     (sm->init_phase2 ? config->engine2 : config->engine) == 0)) {
40		wpa_printf(MSG_INFO, "EAP-TLS: Private key not configured");
41		return NULL;
42	}
43
44	data = os_zalloc(sizeof(*data));
45	if (data == NULL)
46		return NULL;
47
48	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
49		sm->ssl_ctx;
50
51	if (eap_peer_tls_ssl_init(sm, &data->ssl, config, EAP_TYPE_TLS)) {
52		wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
53		eap_tls_deinit(sm, data);
54		if (config->engine) {
55			wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting Smartcard "
56				   "PIN");
57			eap_sm_request_pin(sm);
58			sm->ignore = TRUE;
59		} else if (config->private_key && !config->private_key_passwd)
60		{
61			wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting private "
62				   "key passphrase");
63			eap_sm_request_passphrase(sm);
64			sm->ignore = TRUE;
65		}
66		return NULL;
67	}
68
69	data->eap_type = EAP_TYPE_TLS;
70
71	return data;
72}
73
74
75#ifdef EAP_UNAUTH_TLS
76static void * eap_unauth_tls_init(struct eap_sm *sm)
77{
78	struct eap_tls_data *data;
79	struct eap_peer_config *config = eap_get_config(sm);
80
81	data = os_zalloc(sizeof(*data));
82	if (data == NULL)
83		return NULL;
84
85	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
86		sm->ssl_ctx;
87
88	if (eap_peer_tls_ssl_init(sm, &data->ssl, config,
89				  EAP_UNAUTH_TLS_TYPE)) {
90		wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
91		eap_tls_deinit(sm, data);
92		return NULL;
93	}
94
95	data->eap_type = EAP_UNAUTH_TLS_TYPE;
96
97	return data;
98}
99#endif /* EAP_UNAUTH_TLS */
100
101
102#ifdef CONFIG_HS20
103static void * eap_wfa_unauth_tls_init(struct eap_sm *sm)
104{
105	struct eap_tls_data *data;
106	struct eap_peer_config *config = eap_get_config(sm);
107
108	data = os_zalloc(sizeof(*data));
109	if (data == NULL)
110		return NULL;
111
112	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
113		sm->ssl_ctx;
114
115	if (eap_peer_tls_ssl_init(sm, &data->ssl, config,
116				  EAP_WFA_UNAUTH_TLS_TYPE)) {
117		wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
118		eap_tls_deinit(sm, data);
119		return NULL;
120	}
121
122	data->eap_type = EAP_WFA_UNAUTH_TLS_TYPE;
123
124	return data;
125}
126#endif /* CONFIG_HS20 */
127
128
129static void eap_tls_free_key(struct eap_tls_data *data)
130{
131	if (data->key_data) {
132		bin_clear_free(data->key_data, EAP_TLS_KEY_LEN + EAP_EMSK_LEN);
133		data->key_data = NULL;
134	}
135}
136
137
138static void eap_tls_deinit(struct eap_sm *sm, void *priv)
139{
140	struct eap_tls_data *data = priv;
141	if (data == NULL)
142		return;
143	eap_peer_tls_ssl_deinit(sm, &data->ssl);
144	eap_tls_free_key(data);
145	os_free(data->session_id);
146	wpabuf_free(data->pending_resp);
147	os_free(data);
148}
149
150
151static struct wpabuf * eap_tls_failure(struct eap_sm *sm,
152				       struct eap_tls_data *data,
153				       struct eap_method_ret *ret, int res,
154				       struct wpabuf *resp, u8 id)
155{
156	wpa_printf(MSG_DEBUG, "EAP-TLS: TLS processing failed");
157
158	ret->methodState = METHOD_DONE;
159	ret->decision = DECISION_FAIL;
160
161	if (resp) {
162		/*
163		 * This is likely an alert message, so send it instead of just
164		 * ACKing the error.
165		 */
166		return resp;
167	}
168
169	return eap_peer_tls_build_ack(id, data->eap_type, 0);
170}
171
172
173static void eap_tls_success(struct eap_sm *sm, struct eap_tls_data *data,
174			    struct eap_method_ret *ret)
175{
176	wpa_printf(MSG_DEBUG, "EAP-TLS: Done");
177
178	ret->methodState = METHOD_DONE;
179	ret->decision = DECISION_UNCOND_SUCC;
180
181	eap_tls_free_key(data);
182	data->key_data = eap_peer_tls_derive_key(sm, &data->ssl,
183						 "client EAP encryption",
184						 EAP_TLS_KEY_LEN +
185						 EAP_EMSK_LEN);
186	if (data->key_data) {
187		wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived key",
188				data->key_data, EAP_TLS_KEY_LEN);
189		wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived EMSK",
190				data->key_data + EAP_TLS_KEY_LEN,
191				EAP_EMSK_LEN);
192	} else {
193		wpa_printf(MSG_INFO, "EAP-TLS: Failed to derive key");
194	}
195
196	os_free(data->session_id);
197	data->session_id = eap_peer_tls_derive_session_id(sm, &data->ssl,
198							  EAP_TYPE_TLS,
199			                                  &data->id_len);
200	if (data->session_id) {
201		wpa_hexdump(MSG_DEBUG, "EAP-TLS: Derived Session-Id",
202			    data->session_id, data->id_len);
203	} else {
204		wpa_printf(MSG_ERROR, "EAP-TLS: Failed to derive Session-Id");
205	}
206}
207
208
209static struct wpabuf * eap_tls_process(struct eap_sm *sm, void *priv,
210				       struct eap_method_ret *ret,
211				       const struct wpabuf *reqData)
212{
213	size_t left;
214	int res;
215	struct wpabuf *resp;
216	u8 flags, id;
217	const u8 *pos;
218	struct eap_tls_data *data = priv;
219	struct wpabuf msg;
220
221	if (sm->waiting_ext_cert_check && data->pending_resp) {
222		struct eap_peer_config *config = eap_get_config(sm);
223
224		if (config->pending_ext_cert_check == EXT_CERT_CHECK_GOOD) {
225			wpa_printf(MSG_DEBUG,
226				   "EAP-TLS: External certificate check succeeded - continue handshake");
227			resp = data->pending_resp;
228			data->pending_resp = NULL;
229			sm->waiting_ext_cert_check = 0;
230			return resp;
231		}
232
233		if (config->pending_ext_cert_check == EXT_CERT_CHECK_BAD) {
234			wpa_printf(MSG_DEBUG,
235				   "EAP-TLS: External certificate check failed - force authentication failure");
236			ret->methodState = METHOD_DONE;
237			ret->decision = DECISION_FAIL;
238			sm->waiting_ext_cert_check = 0;
239			return NULL;
240		}
241
242		wpa_printf(MSG_DEBUG,
243			   "EAP-TLS: Continuing to wait external server certificate validation");
244		return NULL;
245	}
246
247	pos = eap_peer_tls_process_init(sm, &data->ssl, data->eap_type, ret,
248					reqData, &left, &flags);
249	if (pos == NULL)
250		return NULL;
251	id = eap_get_id(reqData);
252
253	if (flags & EAP_TLS_FLAGS_START) {
254		wpa_printf(MSG_DEBUG, "EAP-TLS: Start");
255		left = 0; /* make sure that this frame is empty, even though it
256			   * should always be, anyway */
257	}
258
259	resp = NULL;
260	wpabuf_set(&msg, pos, left);
261	res = eap_peer_tls_process_helper(sm, &data->ssl, data->eap_type, 0,
262					  id, &msg, &resp);
263
264	if (res < 0) {
265		return eap_tls_failure(sm, data, ret, res, resp, id);
266	}
267
268	if (sm->waiting_ext_cert_check) {
269		wpa_printf(MSG_DEBUG,
270			   "EAP-TLS: Waiting external server certificate validation");
271		wpabuf_free(data->pending_resp);
272		data->pending_resp = resp;
273		return NULL;
274	}
275
276	if (tls_connection_established(data->ssl_ctx, data->ssl.conn))
277		eap_tls_success(sm, data, ret);
278
279	if (res == 1) {
280		wpabuf_free(resp);
281		return eap_peer_tls_build_ack(id, data->eap_type, 0);
282	}
283
284	return resp;
285}
286
287
288static Boolean eap_tls_has_reauth_data(struct eap_sm *sm, void *priv)
289{
290	struct eap_tls_data *data = priv;
291	return tls_connection_established(data->ssl_ctx, data->ssl.conn);
292}
293
294
295static void eap_tls_deinit_for_reauth(struct eap_sm *sm, void *priv)
296{
297	struct eap_tls_data *data = priv;
298
299	wpabuf_free(data->pending_resp);
300	data->pending_resp = NULL;
301}
302
303
304static void * eap_tls_init_for_reauth(struct eap_sm *sm, void *priv)
305{
306	struct eap_tls_data *data = priv;
307	eap_tls_free_key(data);
308	os_free(data->session_id);
309	data->session_id = NULL;
310	if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
311		os_free(data);
312		return NULL;
313	}
314	return priv;
315}
316
317
318static int eap_tls_get_status(struct eap_sm *sm, void *priv, char *buf,
319			      size_t buflen, int verbose)
320{
321	struct eap_tls_data *data = priv;
322	return eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
323}
324
325
326static Boolean eap_tls_isKeyAvailable(struct eap_sm *sm, void *priv)
327{
328	struct eap_tls_data *data = priv;
329	return data->key_data != NULL;
330}
331
332
333static u8 * eap_tls_getKey(struct eap_sm *sm, void *priv, size_t *len)
334{
335	struct eap_tls_data *data = priv;
336	u8 *key;
337
338	if (data->key_data == NULL)
339		return NULL;
340
341	key = os_malloc(EAP_TLS_KEY_LEN);
342	if (key == NULL)
343		return NULL;
344
345	*len = EAP_TLS_KEY_LEN;
346	os_memcpy(key, data->key_data, EAP_TLS_KEY_LEN);
347
348	return key;
349}
350
351
352static u8 * eap_tls_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
353{
354	struct eap_tls_data *data = priv;
355	u8 *key;
356
357	if (data->key_data == NULL)
358		return NULL;
359
360	key = os_malloc(EAP_EMSK_LEN);
361	if (key == NULL)
362		return NULL;
363
364	*len = EAP_EMSK_LEN;
365	os_memcpy(key, data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
366
367	return key;
368}
369
370
371static u8 * eap_tls_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
372{
373	struct eap_tls_data *data = priv;
374	u8 *id;
375
376	if (data->session_id == NULL)
377		return NULL;
378
379	id = os_malloc(data->id_len);
380	if (id == NULL)
381		return NULL;
382
383	*len = data->id_len;
384	os_memcpy(id, data->session_id, data->id_len);
385
386	return id;
387}
388
389
390int eap_peer_tls_register(void)
391{
392	struct eap_method *eap;
393
394	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
395				    EAP_VENDOR_IETF, EAP_TYPE_TLS, "TLS");
396	if (eap == NULL)
397		return -1;
398
399	eap->init = eap_tls_init;
400	eap->deinit = eap_tls_deinit;
401	eap->process = eap_tls_process;
402	eap->isKeyAvailable = eap_tls_isKeyAvailable;
403	eap->getKey = eap_tls_getKey;
404	eap->getSessionId = eap_tls_get_session_id;
405	eap->get_status = eap_tls_get_status;
406	eap->has_reauth_data = eap_tls_has_reauth_data;
407	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
408	eap->init_for_reauth = eap_tls_init_for_reauth;
409	eap->get_emsk = eap_tls_get_emsk;
410
411	return eap_peer_method_register(eap);
412}
413
414
415#ifdef EAP_UNAUTH_TLS
416int eap_peer_unauth_tls_register(void)
417{
418	struct eap_method *eap;
419
420	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
421				    EAP_VENDOR_UNAUTH_TLS,
422				    EAP_VENDOR_TYPE_UNAUTH_TLS, "UNAUTH-TLS");
423	if (eap == NULL)
424		return -1;
425
426	eap->init = eap_unauth_tls_init;
427	eap->deinit = eap_tls_deinit;
428	eap->process = eap_tls_process;
429	eap->isKeyAvailable = eap_tls_isKeyAvailable;
430	eap->getKey = eap_tls_getKey;
431	eap->get_status = eap_tls_get_status;
432	eap->has_reauth_data = eap_tls_has_reauth_data;
433	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
434	eap->init_for_reauth = eap_tls_init_for_reauth;
435	eap->get_emsk = eap_tls_get_emsk;
436
437	return eap_peer_method_register(eap);
438}
439#endif /* EAP_UNAUTH_TLS */
440
441
442#ifdef CONFIG_HS20
443int eap_peer_wfa_unauth_tls_register(void)
444{
445	struct eap_method *eap;
446
447	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
448				    EAP_VENDOR_WFA_NEW,
449				    EAP_VENDOR_WFA_UNAUTH_TLS,
450				    "WFA-UNAUTH-TLS");
451	if (eap == NULL)
452		return -1;
453
454	eap->init = eap_wfa_unauth_tls_init;
455	eap->deinit = eap_tls_deinit;
456	eap->process = eap_tls_process;
457	eap->isKeyAvailable = eap_tls_isKeyAvailable;
458	eap->getKey = eap_tls_getKey;
459	eap->get_status = eap_tls_get_status;
460	eap->has_reauth_data = eap_tls_has_reauth_data;
461	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
462	eap->init_for_reauth = eap_tls_init_for_reauth;
463	eap->get_emsk = eap_tls_get_emsk;
464
465	return eap_peer_method_register(eap);
466}
467#endif /* CONFIG_HS20 */
468