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	const char *label;
177	const u8 eap_tls13_context[] = { EAP_TYPE_TLS };
178	const u8 *context = NULL;
179	size_t context_len = 0;
180
181	wpa_printf(MSG_DEBUG, "EAP-TLS: Done");
182
183	if (data->ssl.tls_out) {
184		wpa_printf(MSG_DEBUG, "EAP-TLS: Fragment(s) remaining");
185		return;
186	}
187
188	if (data->ssl.tls_v13) {
189		label = "EXPORTER_EAP_TLS_Key_Material";
190		context = eap_tls13_context;
191		context_len = 1;
192
193		/* A possible NewSessionTicket may be received before
194		 * EAP-Success, so need to allow it to be received. */
195		ret->methodState = METHOD_MAY_CONT;
196		ret->decision = DECISION_COND_SUCC;
197	} else {
198		label = "client EAP encryption";
199
200		ret->methodState = METHOD_DONE;
201		ret->decision = DECISION_UNCOND_SUCC;
202	}
203
204	eap_tls_free_key(data);
205	data->key_data = eap_peer_tls_derive_key(sm, &data->ssl, label,
206						 context, context_len,
207						 EAP_TLS_KEY_LEN +
208						 EAP_EMSK_LEN);
209	if (data->key_data) {
210		wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived key",
211				data->key_data, EAP_TLS_KEY_LEN);
212		wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived EMSK",
213				data->key_data + EAP_TLS_KEY_LEN,
214				EAP_EMSK_LEN);
215	} else {
216		wpa_printf(MSG_INFO, "EAP-TLS: Failed to derive key");
217	}
218
219	os_free(data->session_id);
220	data->session_id = eap_peer_tls_derive_session_id(sm, &data->ssl,
221							  EAP_TYPE_TLS,
222			                                  &data->id_len);
223	if (data->session_id) {
224		wpa_hexdump(MSG_DEBUG, "EAP-TLS: Derived Session-Id",
225			    data->session_id, data->id_len);
226	} else {
227		wpa_printf(MSG_ERROR, "EAP-TLS: Failed to derive Session-Id");
228	}
229}
230
231
232static struct wpabuf * eap_tls_process(struct eap_sm *sm, void *priv,
233				       struct eap_method_ret *ret,
234				       const struct wpabuf *reqData)
235{
236	size_t left;
237	int res;
238	struct wpabuf *resp;
239	u8 flags, id;
240	const u8 *pos;
241	struct eap_tls_data *data = priv;
242	struct wpabuf msg;
243
244	if (sm->waiting_ext_cert_check && data->pending_resp) {
245		struct eap_peer_config *config = eap_get_config(sm);
246
247		if (config->pending_ext_cert_check == EXT_CERT_CHECK_GOOD) {
248			wpa_printf(MSG_DEBUG,
249				   "EAP-TLS: External certificate check succeeded - continue handshake");
250			resp = data->pending_resp;
251			data->pending_resp = NULL;
252			sm->waiting_ext_cert_check = 0;
253			return resp;
254		}
255
256		if (config->pending_ext_cert_check == EXT_CERT_CHECK_BAD) {
257			wpa_printf(MSG_DEBUG,
258				   "EAP-TLS: External certificate check failed - force authentication failure");
259			ret->methodState = METHOD_DONE;
260			ret->decision = DECISION_FAIL;
261			sm->waiting_ext_cert_check = 0;
262			return NULL;
263		}
264
265		wpa_printf(MSG_DEBUG,
266			   "EAP-TLS: Continuing to wait external server certificate validation");
267		return NULL;
268	}
269
270	pos = eap_peer_tls_process_init(sm, &data->ssl, data->eap_type, ret,
271					reqData, &left, &flags);
272	if (pos == NULL)
273		return NULL;
274	id = eap_get_id(reqData);
275
276	if (flags & EAP_TLS_FLAGS_START) {
277		wpa_printf(MSG_DEBUG, "EAP-TLS: Start");
278		left = 0; /* make sure that this frame is empty, even though it
279			   * should always be, anyway */
280	}
281
282	resp = NULL;
283	wpabuf_set(&msg, pos, left);
284	res = eap_peer_tls_process_helper(sm, &data->ssl, data->eap_type, 0,
285					  id, &msg, &resp);
286
287	if (res < 0) {
288		return eap_tls_failure(sm, data, ret, res, resp, id);
289	}
290
291	if (sm->waiting_ext_cert_check) {
292		wpa_printf(MSG_DEBUG,
293			   "EAP-TLS: Waiting external server certificate validation");
294		wpabuf_free(data->pending_resp);
295		data->pending_resp = resp;
296		return NULL;
297	}
298
299	if (res == 2) {
300		/* Application data included in the handshake message (used by
301		 * EAP-TLS 1.3 to indicate conclusion of the exchange). */
302		wpa_hexdump_buf(MSG_DEBUG, "EAP-TLS: Received Application Data",
303				resp);
304		wpa_hexdump_buf(MSG_DEBUG, "EAP-TLS: Remaining tls_out data",
305				data->ssl.tls_out);
306		eap_peer_tls_reset_output(&data->ssl);
307		/* Send an ACK to allow the server to complete exchange */
308		res = 1;
309	}
310
311	if (tls_connection_established(data->ssl_ctx, data->ssl.conn))
312		eap_tls_success(sm, data, ret);
313
314	if (res == 1) {
315		wpabuf_free(resp);
316		return eap_peer_tls_build_ack(id, data->eap_type, 0);
317	}
318
319	return resp;
320}
321
322
323static Boolean eap_tls_has_reauth_data(struct eap_sm *sm, void *priv)
324{
325	struct eap_tls_data *data = priv;
326	return tls_connection_established(data->ssl_ctx, data->ssl.conn);
327}
328
329
330static void eap_tls_deinit_for_reauth(struct eap_sm *sm, void *priv)
331{
332	struct eap_tls_data *data = priv;
333
334	wpabuf_free(data->pending_resp);
335	data->pending_resp = NULL;
336}
337
338
339static void * eap_tls_init_for_reauth(struct eap_sm *sm, void *priv)
340{
341	struct eap_tls_data *data = priv;
342	eap_tls_free_key(data);
343	os_free(data->session_id);
344	data->session_id = NULL;
345	if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
346		os_free(data);
347		return NULL;
348	}
349	return priv;
350}
351
352
353static int eap_tls_get_status(struct eap_sm *sm, void *priv, char *buf,
354			      size_t buflen, int verbose)
355{
356	struct eap_tls_data *data = priv;
357	return eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
358}
359
360
361static Boolean eap_tls_isKeyAvailable(struct eap_sm *sm, void *priv)
362{
363	struct eap_tls_data *data = priv;
364	return data->key_data != NULL;
365}
366
367
368static u8 * eap_tls_getKey(struct eap_sm *sm, void *priv, size_t *len)
369{
370	struct eap_tls_data *data = priv;
371	u8 *key;
372
373	if (data->key_data == NULL)
374		return NULL;
375
376	key = os_memdup(data->key_data, EAP_TLS_KEY_LEN);
377	if (key == NULL)
378		return NULL;
379
380	*len = EAP_TLS_KEY_LEN;
381
382	return key;
383}
384
385
386static u8 * eap_tls_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
387{
388	struct eap_tls_data *data = priv;
389	u8 *key;
390
391	if (data->key_data == NULL)
392		return NULL;
393
394	key = os_memdup(data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
395	if (key == NULL)
396		return NULL;
397
398	*len = EAP_EMSK_LEN;
399
400	return key;
401}
402
403
404static u8 * eap_tls_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
405{
406	struct eap_tls_data *data = priv;
407	u8 *id;
408
409	if (data->session_id == NULL)
410		return NULL;
411
412	id = os_memdup(data->session_id, data->id_len);
413	if (id == NULL)
414		return NULL;
415
416	*len = data->id_len;
417
418	return id;
419}
420
421
422int eap_peer_tls_register(void)
423{
424	struct eap_method *eap;
425
426	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
427				    EAP_VENDOR_IETF, EAP_TYPE_TLS, "TLS");
428	if (eap == NULL)
429		return -1;
430
431	eap->init = eap_tls_init;
432	eap->deinit = eap_tls_deinit;
433	eap->process = eap_tls_process;
434	eap->isKeyAvailable = eap_tls_isKeyAvailable;
435	eap->getKey = eap_tls_getKey;
436	eap->getSessionId = eap_tls_get_session_id;
437	eap->get_status = eap_tls_get_status;
438	eap->has_reauth_data = eap_tls_has_reauth_data;
439	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
440	eap->init_for_reauth = eap_tls_init_for_reauth;
441	eap->get_emsk = eap_tls_get_emsk;
442
443	return eap_peer_method_register(eap);
444}
445
446
447#ifdef EAP_UNAUTH_TLS
448int eap_peer_unauth_tls_register(void)
449{
450	struct eap_method *eap;
451
452	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
453				    EAP_VENDOR_UNAUTH_TLS,
454				    EAP_VENDOR_TYPE_UNAUTH_TLS, "UNAUTH-TLS");
455	if (eap == NULL)
456		return -1;
457
458	eap->init = eap_unauth_tls_init;
459	eap->deinit = eap_tls_deinit;
460	eap->process = eap_tls_process;
461	eap->isKeyAvailable = eap_tls_isKeyAvailable;
462	eap->getKey = eap_tls_getKey;
463	eap->get_status = eap_tls_get_status;
464	eap->has_reauth_data = eap_tls_has_reauth_data;
465	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
466	eap->init_for_reauth = eap_tls_init_for_reauth;
467	eap->get_emsk = eap_tls_get_emsk;
468
469	return eap_peer_method_register(eap);
470}
471#endif /* EAP_UNAUTH_TLS */
472
473
474#ifdef CONFIG_HS20
475int eap_peer_wfa_unauth_tls_register(void)
476{
477	struct eap_method *eap;
478
479	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
480				    EAP_VENDOR_WFA_NEW,
481				    EAP_VENDOR_WFA_UNAUTH_TLS,
482				    "WFA-UNAUTH-TLS");
483	if (eap == NULL)
484		return -1;
485
486	eap->init = eap_wfa_unauth_tls_init;
487	eap->deinit = eap_tls_deinit;
488	eap->process = eap_tls_process;
489	eap->isKeyAvailable = eap_tls_isKeyAvailable;
490	eap->getKey = eap_tls_getKey;
491	eap->get_status = eap_tls_get_status;
492	eap->has_reauth_data = eap_tls_has_reauth_data;
493	eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
494	eap->init_for_reauth = eap_tls_init_for_reauth;
495	eap->get_emsk = eap_tls_get_emsk;
496
497	return eap_peer_method_register(eap);
498}
499#endif /* CONFIG_HS20 */
500