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1 /*
2  * EAP-FAST server (RFC 4851)
3  * Copyright (c) 2004-2008, 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/aes_wrap.h"
13 #include "crypto/sha1.h"
14 #include "crypto/tls.h"
15 #include "crypto/random.h"
16 #include "eap_common/eap_tlv_common.h"
17 #include "eap_common/eap_fast_common.h"
18 #include "eap_i.h"
19 #include "eap_tls_common.h"
20 
21 
22 static void eap_fast_reset(struct eap_sm *sm, void *priv);
23 
24 
25 /* Private PAC-Opaque TLV types */
26 #define PAC_OPAQUE_TYPE_PAD 0
27 #define PAC_OPAQUE_TYPE_KEY 1
28 #define PAC_OPAQUE_TYPE_LIFETIME 2
29 #define PAC_OPAQUE_TYPE_IDENTITY 3
30 
31 struct eap_fast_data {
32 	struct eap_ssl_data ssl;
33 	enum {
34 		START, PHASE1, PHASE2_START, PHASE2_ID, PHASE2_METHOD,
35 		CRYPTO_BINDING, REQUEST_PAC, SUCCESS, FAILURE
36 	} state;
37 
38 	int fast_version;
39 	const struct eap_method *phase2_method;
40 	void *phase2_priv;
41 	int force_version;
42 	int peer_version;
43 
44 	u8 crypto_binding_nonce[32];
45 	int final_result;
46 
47 	struct eap_fast_key_block_provisioning *key_block_p;
48 
49 	u8 simck[EAP_FAST_SIMCK_LEN];
50 	u8 cmk[EAP_FAST_CMK_LEN];
51 	int simck_idx;
52 
53 	u8 pac_opaque_encr[16];
54 	u8 *srv_id;
55 	size_t srv_id_len;
56 	char *srv_id_info;
57 
58 	int anon_provisioning;
59 	int send_new_pac; /* server triggered re-keying of Tunnel PAC */
60 	struct wpabuf *pending_phase2_resp;
61 	u8 *identity; /* from PAC-Opaque */
62 	size_t identity_len;
63 	int eap_seq;
64 	int tnc_started;
65 
66 	int pac_key_lifetime;
67 	int pac_key_refresh_time;
68 };
69 
70 
71 static int eap_fast_process_phase2_start(struct eap_sm *sm,
72 					 struct eap_fast_data *data);
73 
74 
eap_fast_state_txt(int state)75 static const char * eap_fast_state_txt(int state)
76 {
77 	switch (state) {
78 	case START:
79 		return "START";
80 	case PHASE1:
81 		return "PHASE1";
82 	case PHASE2_START:
83 		return "PHASE2_START";
84 	case PHASE2_ID:
85 		return "PHASE2_ID";
86 	case PHASE2_METHOD:
87 		return "PHASE2_METHOD";
88 	case CRYPTO_BINDING:
89 		return "CRYPTO_BINDING";
90 	case REQUEST_PAC:
91 		return "REQUEST_PAC";
92 	case SUCCESS:
93 		return "SUCCESS";
94 	case FAILURE:
95 		return "FAILURE";
96 	default:
97 		return "Unknown?!";
98 	}
99 }
100 
101 
eap_fast_state(struct eap_fast_data * data,int state)102 static void eap_fast_state(struct eap_fast_data *data, int state)
103 {
104 	wpa_printf(MSG_DEBUG, "EAP-FAST: %s -> %s",
105 		   eap_fast_state_txt(data->state),
106 		   eap_fast_state_txt(state));
107 	data->state = state;
108 }
109 
110 
eap_fast_req_failure(struct eap_sm * sm,struct eap_fast_data * data)111 static EapType eap_fast_req_failure(struct eap_sm *sm,
112 				    struct eap_fast_data *data)
113 {
114 	/* TODO: send Result TLV(FAILURE) */
115 	eap_fast_state(data, FAILURE);
116 	return EAP_TYPE_NONE;
117 }
118 
119 
eap_fast_session_ticket_cb(void * ctx,const u8 * ticket,size_t len,const u8 * client_random,const u8 * server_random,u8 * master_secret)120 static int eap_fast_session_ticket_cb(void *ctx, const u8 *ticket, size_t len,
121 				      const u8 *client_random,
122 				      const u8 *server_random,
123 				      u8 *master_secret)
124 {
125 	struct eap_fast_data *data = ctx;
126 	const u8 *pac_opaque;
127 	size_t pac_opaque_len;
128 	u8 *buf, *pos, *end, *pac_key = NULL;
129 	os_time_t lifetime = 0;
130 	struct os_time now;
131 	u8 *identity = NULL;
132 	size_t identity_len = 0;
133 
134 	wpa_printf(MSG_DEBUG, "EAP-FAST: SessionTicket callback");
135 	wpa_hexdump(MSG_DEBUG, "EAP-FAST: SessionTicket (PAC-Opaque)",
136 		    ticket, len);
137 
138 	if (len < 4 || WPA_GET_BE16(ticket) != PAC_TYPE_PAC_OPAQUE) {
139 		wpa_printf(MSG_DEBUG, "EAP-FAST: Ignore invalid "
140 			   "SessionTicket");
141 		return 0;
142 	}
143 
144 	pac_opaque_len = WPA_GET_BE16(ticket + 2);
145 	pac_opaque = ticket + 4;
146 	if (pac_opaque_len < 8 || pac_opaque_len % 8 ||
147 	    pac_opaque_len > len - 4) {
148 		wpa_printf(MSG_DEBUG, "EAP-FAST: Ignore invalid PAC-Opaque "
149 			   "(len=%lu left=%lu)",
150 			   (unsigned long) pac_opaque_len,
151 			   (unsigned long) len);
152 		return 0;
153 	}
154 	wpa_hexdump(MSG_DEBUG, "EAP-FAST: Received PAC-Opaque",
155 		    pac_opaque, pac_opaque_len);
156 
157 	buf = os_malloc(pac_opaque_len - 8);
158 	if (buf == NULL) {
159 		wpa_printf(MSG_DEBUG, "EAP-FAST: Failed to allocate memory "
160 			   "for decrypting PAC-Opaque");
161 		return 0;
162 	}
163 
164 	if (aes_unwrap(data->pac_opaque_encr, sizeof(data->pac_opaque_encr),
165 		       (pac_opaque_len - 8) / 8, pac_opaque, buf) < 0) {
166 		wpa_printf(MSG_DEBUG, "EAP-FAST: Failed to decrypt "
167 			   "PAC-Opaque");
168 		os_free(buf);
169 		/*
170 		 * This may have been caused by server changing the PAC-Opaque
171 		 * encryption key, so just ignore this PAC-Opaque instead of
172 		 * failing the authentication completely. Provisioning can now
173 		 * be used to provision a new PAC.
174 		 */
175 		return 0;
176 	}
177 
178 	end = buf + pac_opaque_len - 8;
179 	wpa_hexdump_key(MSG_DEBUG, "EAP-FAST: Decrypted PAC-Opaque",
180 			buf, end - buf);
181 
182 	pos = buf;
183 	while (end - pos > 1) {
184 		u8 id, elen;
185 
186 		id = *pos++;
187 		elen = *pos++;
188 		if (elen > end - pos)
189 			break;
190 
191 		switch (id) {
192 		case PAC_OPAQUE_TYPE_PAD:
193 			goto done;
194 		case PAC_OPAQUE_TYPE_KEY:
195 			if (elen != EAP_FAST_PAC_KEY_LEN) {
196 				wpa_printf(MSG_DEBUG,
197 					   "EAP-FAST: Invalid PAC-Key length %d",
198 					   elen);
199 				os_free(buf);
200 				return -1;
201 			}
202 			pac_key = pos;
203 			wpa_hexdump_key(MSG_DEBUG, "EAP-FAST: PAC-Key from "
204 					"decrypted PAC-Opaque",
205 					pac_key, EAP_FAST_PAC_KEY_LEN);
206 			break;
207 		case PAC_OPAQUE_TYPE_LIFETIME:
208 			if (elen != 4) {
209 				wpa_printf(MSG_DEBUG, "EAP-FAST: Invalid "
210 					   "PAC-Key lifetime length %d",
211 					   elen);
212 				os_free(buf);
213 				return -1;
214 			}
215 			lifetime = WPA_GET_BE32(pos);
216 			break;
217 		case PAC_OPAQUE_TYPE_IDENTITY:
218 			identity = pos;
219 			identity_len = elen;
220 			break;
221 		}
222 
223 		pos += elen;
224 	}
225 done:
226 
227 	if (pac_key == NULL) {
228 		wpa_printf(MSG_DEBUG, "EAP-FAST: No PAC-Key included in "
229 			   "PAC-Opaque");
230 		os_free(buf);
231 		return -1;
232 	}
233 
234 	if (identity) {
235 		wpa_hexdump_ascii(MSG_DEBUG, "EAP-FAST: Identity from "
236 				  "PAC-Opaque", identity, identity_len);
237 		os_free(data->identity);
238 		data->identity = os_malloc(identity_len);
239 		if (data->identity) {
240 			os_memcpy(data->identity, identity, identity_len);
241 			data->identity_len = identity_len;
242 		}
243 	}
244 
245 	if (os_get_time(&now) < 0 || lifetime <= 0 || now.sec > lifetime) {
246 		wpa_printf(MSG_DEBUG, "EAP-FAST: PAC-Key not valid anymore "
247 			   "(lifetime=%ld now=%ld)", lifetime, now.sec);
248 		data->send_new_pac = 2;
249 		/*
250 		 * Allow PAC to be used to allow a PAC update with some level
251 		 * of server authentication (i.e., do not fall back to full TLS
252 		 * handshake since we cannot be sure that the peer would be
253 		 * able to validate server certificate now). However, reject
254 		 * the authentication since the PAC was not valid anymore. Peer
255 		 * can connect again with the newly provisioned PAC after this.
256 		 */
257 	} else if (lifetime - now.sec < data->pac_key_refresh_time) {
258 		wpa_printf(MSG_DEBUG, "EAP-FAST: PAC-Key soft timeout; send "
259 			   "an update if authentication succeeds");
260 		data->send_new_pac = 1;
261 	}
262 
263 	eap_fast_derive_master_secret(pac_key, server_random, client_random,
264 				      master_secret);
265 
266 	os_free(buf);
267 
268 	return 1;
269 }
270 
271 
eap_fast_derive_key_auth(struct eap_sm * sm,struct eap_fast_data * data)272 static void eap_fast_derive_key_auth(struct eap_sm *sm,
273 				     struct eap_fast_data *data)
274 {
275 	u8 *sks;
276 
277 	/* RFC 4851, Section 5.1:
278 	 * Extra key material after TLS key_block: session_key_seed[40]
279 	 */
280 
281 	sks = eap_fast_derive_key(sm->ssl_ctx, data->ssl.conn,
282 				  EAP_FAST_SKS_LEN);
283 	if (sks == NULL) {
284 		wpa_printf(MSG_DEBUG, "EAP-FAST: Failed to derive "
285 			   "session_key_seed");
286 		return;
287 	}
288 
289 	/*
290 	 * RFC 4851, Section 5.2:
291 	 * S-IMCK[0] = session_key_seed
292 	 */
293 	wpa_hexdump_key(MSG_DEBUG,
294 			"EAP-FAST: session_key_seed (SKS = S-IMCK[0])",
295 			sks, EAP_FAST_SKS_LEN);
296 	data->simck_idx = 0;
297 	os_memcpy(data->simck, sks, EAP_FAST_SIMCK_LEN);
298 	os_free(sks);
299 }
300 
301 
eap_fast_derive_key_provisioning(struct eap_sm * sm,struct eap_fast_data * data)302 static void eap_fast_derive_key_provisioning(struct eap_sm *sm,
303 					     struct eap_fast_data *data)
304 {
305 	os_free(data->key_block_p);
306 	data->key_block_p = (struct eap_fast_key_block_provisioning *)
307 		eap_fast_derive_key(sm->ssl_ctx, data->ssl.conn,
308 				    sizeof(*data->key_block_p));
309 	if (data->key_block_p == NULL) {
310 		wpa_printf(MSG_DEBUG, "EAP-FAST: Failed to derive key block");
311 		return;
312 	}
313 	/*
314 	 * RFC 4851, Section 5.2:
315 	 * S-IMCK[0] = session_key_seed
316 	 */
317 	wpa_hexdump_key(MSG_DEBUG,
318 			"EAP-FAST: session_key_seed (SKS = S-IMCK[0])",
319 			data->key_block_p->session_key_seed,
320 			sizeof(data->key_block_p->session_key_seed));
321 	data->simck_idx = 0;
322 	os_memcpy(data->simck, data->key_block_p->session_key_seed,
323 		  EAP_FAST_SIMCK_LEN);
324 	wpa_hexdump_key(MSG_DEBUG, "EAP-FAST: server_challenge",
325 			data->key_block_p->server_challenge,
326 			sizeof(data->key_block_p->server_challenge));
327 	wpa_hexdump_key(MSG_DEBUG, "EAP-FAST: client_challenge",
328 			data->key_block_p->client_challenge,
329 			sizeof(data->key_block_p->client_challenge));
330 }
331 
332 
eap_fast_get_phase2_key(struct eap_sm * sm,struct eap_fast_data * data,u8 * isk,size_t isk_len)333 static int eap_fast_get_phase2_key(struct eap_sm *sm,
334 				   struct eap_fast_data *data,
335 				   u8 *isk, size_t isk_len)
336 {
337 	u8 *key;
338 	size_t key_len;
339 
340 	os_memset(isk, 0, isk_len);
341 
342 	if (data->phase2_method == NULL || data->phase2_priv == NULL) {
343 		wpa_printf(MSG_DEBUG, "EAP-FAST: Phase 2 method not "
344 			   "available");
345 		return -1;
346 	}
347 
348 	if (data->phase2_method->getKey == NULL)
349 		return 0;
350 
351 	if ((key = data->phase2_method->getKey(sm, data->phase2_priv,
352 					       &key_len)) == NULL) {
353 		wpa_printf(MSG_DEBUG, "EAP-FAST: Could not get key material "
354 			   "from Phase 2");
355 		return -1;
356 	}
357 
358 	if (key_len > isk_len)
359 		key_len = isk_len;
360 	if (key_len == 32 &&
361 	    data->phase2_method->vendor == EAP_VENDOR_IETF &&
362 	    data->phase2_method->method == EAP_TYPE_MSCHAPV2) {
363 		/*
364 		 * EAP-FAST uses reverse order for MS-MPPE keys when deriving
365 		 * MSK from EAP-MSCHAPv2. Swap the keys here to get the correct
366 		 * ISK for EAP-FAST cryptobinding.
367 		 */
368 		os_memcpy(isk, key + 16, 16);
369 		os_memcpy(isk + 16, key, 16);
370 	} else
371 		os_memcpy(isk, key, key_len);
372 	os_free(key);
373 
374 	return 0;
375 }
376 
377 
eap_fast_update_icmk(struct eap_sm * sm,struct eap_fast_data * data)378 static int eap_fast_update_icmk(struct eap_sm *sm, struct eap_fast_data *data)
379 {
380 	u8 isk[32], imck[60];
381 
382 	wpa_printf(MSG_DEBUG, "EAP-FAST: Deriving ICMK[%d] (S-IMCK and CMK)",
383 		   data->simck_idx + 1);
384 
385 	/*
386 	 * RFC 4851, Section 5.2:
387 	 * IMCK[j] = T-PRF(S-IMCK[j-1], "Inner Methods Compound Keys",
388 	 *                 MSK[j], 60)
389 	 * S-IMCK[j] = first 40 octets of IMCK[j]
390 	 * CMK[j] = last 20 octets of IMCK[j]
391 	 */
392 
393 	if (eap_fast_get_phase2_key(sm, data, isk, sizeof(isk)) < 0)
394 		return -1;
395 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-FAST: ISK[j]", isk, sizeof(isk));
396 	sha1_t_prf(data->simck, EAP_FAST_SIMCK_LEN,
397 		   "Inner Methods Compound Keys",
398 		   isk, sizeof(isk), imck, sizeof(imck));
399 	data->simck_idx++;
400 	os_memcpy(data->simck, imck, EAP_FAST_SIMCK_LEN);
401 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-FAST: S-IMCK[j]",
402 			data->simck, EAP_FAST_SIMCK_LEN);
403 	os_memcpy(data->cmk, imck + EAP_FAST_SIMCK_LEN, EAP_FAST_CMK_LEN);
404 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-FAST: CMK[j]",
405 			data->cmk, EAP_FAST_CMK_LEN);
406 
407 	return 0;
408 }
409 
410 
eap_fast_init(struct eap_sm * sm)411 static void * eap_fast_init(struct eap_sm *sm)
412 {
413 	struct eap_fast_data *data;
414 	u8 ciphers[7] = {
415 		TLS_CIPHER_ANON_DH_AES128_SHA,
416 		TLS_CIPHER_AES128_SHA,
417 		TLS_CIPHER_RSA_DHE_AES128_SHA,
418 		TLS_CIPHER_RC4_SHA,
419 		TLS_CIPHER_RSA_DHE_AES256_SHA,
420 		TLS_CIPHER_AES256_SHA,
421 		TLS_CIPHER_NONE
422 	};
423 
424 	data = os_zalloc(sizeof(*data));
425 	if (data == NULL)
426 		return NULL;
427 	data->fast_version = EAP_FAST_VERSION;
428 	data->force_version = -1;
429 	if (sm->user && sm->user->force_version >= 0) {
430 		data->force_version = sm->user->force_version;
431 		wpa_printf(MSG_DEBUG, "EAP-FAST: forcing version %d",
432 			   data->force_version);
433 		data->fast_version = data->force_version;
434 	}
435 	data->state = START;
436 
437 	if (eap_server_tls_ssl_init(sm, &data->ssl, 0, EAP_TYPE_FAST)) {
438 		wpa_printf(MSG_INFO, "EAP-FAST: Failed to initialize SSL.");
439 		eap_fast_reset(sm, data);
440 		return NULL;
441 	}
442 
443 	if (tls_connection_set_cipher_list(sm->ssl_ctx, data->ssl.conn,
444 					   ciphers) < 0) {
445 		wpa_printf(MSG_INFO, "EAP-FAST: Failed to set TLS cipher "
446 			   "suites");
447 		eap_fast_reset(sm, data);
448 		return NULL;
449 	}
450 
451 	if (tls_connection_set_session_ticket_cb(sm->ssl_ctx, data->ssl.conn,
452 						 eap_fast_session_ticket_cb,
453 						 data) < 0) {
454 		wpa_printf(MSG_INFO, "EAP-FAST: Failed to set SessionTicket "
455 			   "callback");
456 		eap_fast_reset(sm, data);
457 		return NULL;
458 	}
459 
460 	if (sm->pac_opaque_encr_key == NULL) {
461 		wpa_printf(MSG_INFO, "EAP-FAST: No PAC-Opaque encryption key "
462 			   "configured");
463 		eap_fast_reset(sm, data);
464 		return NULL;
465 	}
466 	os_memcpy(data->pac_opaque_encr, sm->pac_opaque_encr_key,
467 		  sizeof(data->pac_opaque_encr));
468 
469 	if (sm->eap_fast_a_id == NULL) {
470 		wpa_printf(MSG_INFO, "EAP-FAST: No A-ID configured");
471 		eap_fast_reset(sm, data);
472 		return NULL;
473 	}
474 	data->srv_id = os_malloc(sm->eap_fast_a_id_len);
475 	if (data->srv_id == NULL) {
476 		eap_fast_reset(sm, data);
477 		return NULL;
478 	}
479 	os_memcpy(data->srv_id, sm->eap_fast_a_id, sm->eap_fast_a_id_len);
480 	data->srv_id_len = sm->eap_fast_a_id_len;
481 
482 	if (sm->eap_fast_a_id_info == NULL) {
483 		wpa_printf(MSG_INFO, "EAP-FAST: No A-ID-Info configured");
484 		eap_fast_reset(sm, data);
485 		return NULL;
486 	}
487 	data->srv_id_info = os_strdup(sm->eap_fast_a_id_info);
488 	if (data->srv_id_info == NULL) {
489 		eap_fast_reset(sm, data);
490 		return NULL;
491 	}
492 
493 	/* PAC-Key lifetime in seconds (hard limit) */
494 	data->pac_key_lifetime = sm->pac_key_lifetime;
495 
496 	/*
497 	 * PAC-Key refresh time in seconds (soft limit on remaining hard
498 	 * limit). The server will generate a new PAC-Key when this number of
499 	 * seconds (or fewer) of the lifetime remains.
500 	 */
501 	data->pac_key_refresh_time = sm->pac_key_refresh_time;
502 
503 	return data;
504 }
505 
506 
eap_fast_reset(struct eap_sm * sm,void * priv)507 static void eap_fast_reset(struct eap_sm *sm, void *priv)
508 {
509 	struct eap_fast_data *data = priv;
510 	if (data == NULL)
511 		return;
512 	if (data->phase2_priv && data->phase2_method)
513 		data->phase2_method->reset(sm, data->phase2_priv);
514 	eap_server_tls_ssl_deinit(sm, &data->ssl);
515 	os_free(data->srv_id);
516 	os_free(data->srv_id_info);
517 	os_free(data->key_block_p);
518 	wpabuf_free(data->pending_phase2_resp);
519 	os_free(data->identity);
520 	bin_clear_free(data, sizeof(*data));
521 }
522 
523 
eap_fast_build_start(struct eap_sm * sm,struct eap_fast_data * data,u8 id)524 static struct wpabuf * eap_fast_build_start(struct eap_sm *sm,
525 					    struct eap_fast_data *data, u8 id)
526 {
527 	struct wpabuf *req;
528 
529 	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_FAST,
530 			    1 + sizeof(struct pac_tlv_hdr) + data->srv_id_len,
531 			    EAP_CODE_REQUEST, id);
532 	if (req == NULL) {
533 		wpa_printf(MSG_ERROR, "EAP-FAST: Failed to allocate memory for"
534 			   " request");
535 		eap_fast_state(data, FAILURE);
536 		return NULL;
537 	}
538 
539 	wpabuf_put_u8(req, EAP_TLS_FLAGS_START | data->fast_version);
540 
541 	/* RFC 4851, 4.1.1. Authority ID Data */
542 	eap_fast_put_tlv(req, PAC_TYPE_A_ID, data->srv_id, data->srv_id_len);
543 
544 	eap_fast_state(data, PHASE1);
545 
546 	return req;
547 }
548 
549 
eap_fast_phase1_done(struct eap_sm * sm,struct eap_fast_data * data)550 static int eap_fast_phase1_done(struct eap_sm *sm, struct eap_fast_data *data)
551 {
552 	char cipher[64];
553 
554 	wpa_printf(MSG_DEBUG, "EAP-FAST: Phase1 done, starting Phase2");
555 
556 	if (tls_get_cipher(sm->ssl_ctx, data->ssl.conn, cipher, sizeof(cipher))
557 	    < 0) {
558 		wpa_printf(MSG_DEBUG, "EAP-FAST: Failed to get cipher "
559 			   "information");
560 		eap_fast_state(data, FAILURE);
561 		return -1;
562 	}
563 	data->anon_provisioning = os_strstr(cipher, "ADH") != NULL;
564 
565 	if (data->anon_provisioning) {
566 		wpa_printf(MSG_DEBUG, "EAP-FAST: Anonymous provisioning");
567 		eap_fast_derive_key_provisioning(sm, data);
568 	} else
569 		eap_fast_derive_key_auth(sm, data);
570 
571 	eap_fast_state(data, PHASE2_START);
572 
573 	return 0;
574 }
575 
576 
eap_fast_build_phase2_req(struct eap_sm * sm,struct eap_fast_data * data,u8 id)577 static struct wpabuf * eap_fast_build_phase2_req(struct eap_sm *sm,
578 						 struct eap_fast_data *data,
579 						 u8 id)
580 {
581 	struct wpabuf *req;
582 
583 	if (data->phase2_priv == NULL) {
584 		wpa_printf(MSG_DEBUG, "EAP-FAST: Phase 2 method not "
585 			   "initialized");
586 		return NULL;
587 	}
588 	req = data->phase2_method->buildReq(sm, data->phase2_priv, id);
589 	if (req == NULL)
590 		return NULL;
591 
592 	wpa_hexdump_buf_key(MSG_MSGDUMP, "EAP-FAST: Phase 2 EAP-Request", req);
593 	return eap_fast_tlv_eap_payload(req);
594 }
595 
596 
eap_fast_build_crypto_binding(struct eap_sm * sm,struct eap_fast_data * data)597 static struct wpabuf * eap_fast_build_crypto_binding(
598 	struct eap_sm *sm, struct eap_fast_data *data)
599 {
600 	struct wpabuf *buf;
601 	struct eap_tlv_result_tlv *result;
602 	struct eap_tlv_crypto_binding_tlv *binding;
603 
604 	buf = wpabuf_alloc(2 * sizeof(*result) + sizeof(*binding));
605 	if (buf == NULL)
606 		return NULL;
607 
608 	if (data->send_new_pac || data->anon_provisioning ||
609 	    data->phase2_method)
610 		data->final_result = 0;
611 	else
612 		data->final_result = 1;
613 
614 	if (!data->final_result || data->eap_seq > 1) {
615 		/* Intermediate-Result */
616 		wpa_printf(MSG_DEBUG, "EAP-FAST: Add Intermediate-Result TLV "
617 			   "(status=SUCCESS)");
618 		result = wpabuf_put(buf, sizeof(*result));
619 		result->tlv_type = host_to_be16(
620 			EAP_TLV_TYPE_MANDATORY |
621 			EAP_TLV_INTERMEDIATE_RESULT_TLV);
622 		result->length = host_to_be16(2);
623 		result->status = host_to_be16(EAP_TLV_RESULT_SUCCESS);
624 	}
625 
626 	if (data->final_result) {
627 		/* Result TLV */
628 		wpa_printf(MSG_DEBUG, "EAP-FAST: Add Result TLV "
629 			   "(status=SUCCESS)");
630 		result = wpabuf_put(buf, sizeof(*result));
631 		result->tlv_type = host_to_be16(EAP_TLV_TYPE_MANDATORY |
632 						EAP_TLV_RESULT_TLV);
633 		result->length = host_to_be16(2);
634 		result->status = host_to_be16(EAP_TLV_RESULT_SUCCESS);
635 	}
636 
637 	/* Crypto-Binding TLV */
638 	binding = wpabuf_put(buf, sizeof(*binding));
639 	binding->tlv_type = host_to_be16(EAP_TLV_TYPE_MANDATORY |
640 					 EAP_TLV_CRYPTO_BINDING_TLV);
641 	binding->length = host_to_be16(sizeof(*binding) -
642 				       sizeof(struct eap_tlv_hdr));
643 	binding->version = EAP_FAST_VERSION;
644 	binding->received_version = data->peer_version;
645 	binding->subtype = EAP_TLV_CRYPTO_BINDING_SUBTYPE_REQUEST;
646 	if (random_get_bytes(binding->nonce, sizeof(binding->nonce)) < 0) {
647 		wpabuf_free(buf);
648 		return NULL;
649 	}
650 
651 	/*
652 	 * RFC 4851, Section 4.2.8:
653 	 * The nonce in a request MUST have its least significant bit set to 0.
654 	 */
655 	binding->nonce[sizeof(binding->nonce) - 1] &= ~0x01;
656 
657 	os_memcpy(data->crypto_binding_nonce, binding->nonce,
658 		  sizeof(binding->nonce));
659 
660 	/*
661 	 * RFC 4851, Section 5.3:
662 	 * CMK = CMK[j]
663 	 * Compound-MAC = HMAC-SHA1( CMK, Crypto-Binding TLV )
664 	 */
665 
666 	hmac_sha1(data->cmk, EAP_FAST_CMK_LEN,
667 		  (u8 *) binding, sizeof(*binding),
668 		  binding->compound_mac);
669 
670 	wpa_printf(MSG_DEBUG, "EAP-FAST: Add Crypto-Binding TLV: Version %d "
671 		   "Received Version %d SubType %d",
672 		   binding->version, binding->received_version,
673 		   binding->subtype);
674 	wpa_hexdump(MSG_MSGDUMP, "EAP-FAST: NONCE",
675 		    binding->nonce, sizeof(binding->nonce));
676 	wpa_hexdump(MSG_MSGDUMP, "EAP-FAST: Compound MAC",
677 		    binding->compound_mac, sizeof(binding->compound_mac));
678 
679 	return buf;
680 }
681 
682 
eap_fast_build_pac(struct eap_sm * sm,struct eap_fast_data * data)683 static struct wpabuf * eap_fast_build_pac(struct eap_sm *sm,
684 					  struct eap_fast_data *data)
685 {
686 	u8 pac_key[EAP_FAST_PAC_KEY_LEN];
687 	u8 *pac_buf, *pac_opaque;
688 	struct wpabuf *buf;
689 	u8 *pos;
690 	size_t buf_len, srv_id_info_len, pac_len;
691 	struct eap_tlv_hdr *pac_tlv;
692 	struct pac_tlv_hdr *pac_info;
693 	struct eap_tlv_result_tlv *result;
694 	struct os_time now;
695 
696 	if (random_get_bytes(pac_key, EAP_FAST_PAC_KEY_LEN) < 0 ||
697 	    os_get_time(&now) < 0)
698 		return NULL;
699 	wpa_hexdump_key(MSG_DEBUG, "EAP-FAST: Generated PAC-Key",
700 			pac_key, EAP_FAST_PAC_KEY_LEN);
701 
702 	pac_len = (2 + EAP_FAST_PAC_KEY_LEN) + (2 + 4) +
703 		(2 + sm->identity_len) + 8;
704 	pac_buf = os_malloc(pac_len);
705 	if (pac_buf == NULL)
706 		return NULL;
707 
708 	srv_id_info_len = os_strlen(data->srv_id_info);
709 
710 	pos = pac_buf;
711 	*pos++ = PAC_OPAQUE_TYPE_KEY;
712 	*pos++ = EAP_FAST_PAC_KEY_LEN;
713 	os_memcpy(pos, pac_key, EAP_FAST_PAC_KEY_LEN);
714 	pos += EAP_FAST_PAC_KEY_LEN;
715 
716 	*pos++ = PAC_OPAQUE_TYPE_LIFETIME;
717 	*pos++ = 4;
718 	WPA_PUT_BE32(pos, now.sec + data->pac_key_lifetime);
719 	pos += 4;
720 
721 	if (sm->identity) {
722 		*pos++ = PAC_OPAQUE_TYPE_IDENTITY;
723 		*pos++ = sm->identity_len;
724 		os_memcpy(pos, sm->identity, sm->identity_len);
725 		pos += sm->identity_len;
726 	}
727 
728 	pac_len = pos - pac_buf;
729 	while (pac_len % 8) {
730 		*pos++ = PAC_OPAQUE_TYPE_PAD;
731 		pac_len++;
732 	}
733 
734 	pac_opaque = os_malloc(pac_len + 8);
735 	if (pac_opaque == NULL) {
736 		os_free(pac_buf);
737 		return NULL;
738 	}
739 	if (aes_wrap(data->pac_opaque_encr, sizeof(data->pac_opaque_encr),
740 		     pac_len / 8, pac_buf, pac_opaque) < 0) {
741 		os_free(pac_buf);
742 		os_free(pac_opaque);
743 		return NULL;
744 	}
745 	os_free(pac_buf);
746 
747 	pac_len += 8;
748 	wpa_hexdump(MSG_DEBUG, "EAP-FAST: PAC-Opaque",
749 		    pac_opaque, pac_len);
750 
751 	buf_len = sizeof(*pac_tlv) +
752 		sizeof(struct pac_tlv_hdr) + EAP_FAST_PAC_KEY_LEN +
753 		sizeof(struct pac_tlv_hdr) + pac_len +
754 		data->srv_id_len + srv_id_info_len + 100 + sizeof(*result);
755 	buf = wpabuf_alloc(buf_len);
756 	if (buf == NULL) {
757 		os_free(pac_opaque);
758 		return NULL;
759 	}
760 
761 	/* Result TLV */
762 	wpa_printf(MSG_DEBUG, "EAP-FAST: Add Result TLV (status=SUCCESS)");
763 	result = wpabuf_put(buf, sizeof(*result));
764 	WPA_PUT_BE16((u8 *) &result->tlv_type,
765 		     EAP_TLV_TYPE_MANDATORY | EAP_TLV_RESULT_TLV);
766 	WPA_PUT_BE16((u8 *) &result->length, 2);
767 	WPA_PUT_BE16((u8 *) &result->status, EAP_TLV_RESULT_SUCCESS);
768 
769 	/* PAC TLV */
770 	wpa_printf(MSG_DEBUG, "EAP-FAST: Add PAC TLV");
771 	pac_tlv = wpabuf_put(buf, sizeof(*pac_tlv));
772 	pac_tlv->tlv_type = host_to_be16(EAP_TLV_TYPE_MANDATORY |
773 					 EAP_TLV_PAC_TLV);
774 
775 	/* PAC-Key */
776 	eap_fast_put_tlv(buf, PAC_TYPE_PAC_KEY, pac_key, EAP_FAST_PAC_KEY_LEN);
777 
778 	/* PAC-Opaque */
779 	eap_fast_put_tlv(buf, PAC_TYPE_PAC_OPAQUE, pac_opaque, pac_len);
780 	os_free(pac_opaque);
781 
782 	/* PAC-Info */
783 	pac_info = wpabuf_put(buf, sizeof(*pac_info));
784 	pac_info->type = host_to_be16(PAC_TYPE_PAC_INFO);
785 
786 	/* PAC-Lifetime (inside PAC-Info) */
787 	eap_fast_put_tlv_hdr(buf, PAC_TYPE_CRED_LIFETIME, 4);
788 	wpabuf_put_be32(buf, now.sec + data->pac_key_lifetime);
789 
790 	/* A-ID (inside PAC-Info) */
791 	eap_fast_put_tlv(buf, PAC_TYPE_A_ID, data->srv_id, data->srv_id_len);
792 
793 	/* Note: headers may be misaligned after A-ID */
794 
795 	if (sm->identity) {
796 		eap_fast_put_tlv(buf, PAC_TYPE_I_ID, sm->identity,
797 				 sm->identity_len);
798 	}
799 
800 	/* A-ID-Info (inside PAC-Info) */
801 	eap_fast_put_tlv(buf, PAC_TYPE_A_ID_INFO, data->srv_id_info,
802 			 srv_id_info_len);
803 
804 	/* PAC-Type (inside PAC-Info) */
805 	eap_fast_put_tlv_hdr(buf, PAC_TYPE_PAC_TYPE, 2);
806 	wpabuf_put_be16(buf, PAC_TYPE_TUNNEL_PAC);
807 
808 	/* Update PAC-Info and PAC TLV Length fields */
809 	pos = wpabuf_put(buf, 0);
810 	pac_info->len = host_to_be16(pos - (u8 *) (pac_info + 1));
811 	pac_tlv->length = host_to_be16(pos - (u8 *) (pac_tlv + 1));
812 
813 	return buf;
814 }
815 
816 
eap_fast_encrypt_phase2(struct eap_sm * sm,struct eap_fast_data * data,struct wpabuf * plain,int piggyback)817 static int eap_fast_encrypt_phase2(struct eap_sm *sm,
818 				   struct eap_fast_data *data,
819 				   struct wpabuf *plain, int piggyback)
820 {
821 	struct wpabuf *encr;
822 
823 	wpa_hexdump_buf_key(MSG_DEBUG, "EAP-FAST: Encrypting Phase 2 TLVs",
824 			    plain);
825 	encr = eap_server_tls_encrypt(sm, &data->ssl, plain);
826 	wpabuf_free(plain);
827 
828 	if (!encr)
829 		return -1;
830 
831 	if (data->ssl.tls_out && piggyback) {
832 		wpa_printf(MSG_DEBUG, "EAP-FAST: Piggyback Phase 2 data "
833 			   "(len=%d) with last Phase 1 Message (len=%d "
834 			   "used=%d)",
835 			   (int) wpabuf_len(encr),
836 			   (int) wpabuf_len(data->ssl.tls_out),
837 			   (int) data->ssl.tls_out_pos);
838 		if (wpabuf_resize(&data->ssl.tls_out, wpabuf_len(encr)) < 0) {
839 			wpa_printf(MSG_WARNING, "EAP-FAST: Failed to resize "
840 				   "output buffer");
841 			wpabuf_free(encr);
842 			return -1;
843 		}
844 		wpabuf_put_buf(data->ssl.tls_out, encr);
845 		wpabuf_free(encr);
846 	} else {
847 		wpabuf_free(data->ssl.tls_out);
848 		data->ssl.tls_out_pos = 0;
849 		data->ssl.tls_out = encr;
850 	}
851 
852 	return 0;
853 }
854 
855 
eap_fast_buildReq(struct eap_sm * sm,void * priv,u8 id)856 static struct wpabuf * eap_fast_buildReq(struct eap_sm *sm, void *priv, u8 id)
857 {
858 	struct eap_fast_data *data = priv;
859 	struct wpabuf *req = NULL;
860 	int piggyback = 0;
861 
862 	if (data->ssl.state == FRAG_ACK) {
863 		return eap_server_tls_build_ack(id, EAP_TYPE_FAST,
864 						data->fast_version);
865 	}
866 
867 	if (data->ssl.state == WAIT_FRAG_ACK) {
868 		return eap_server_tls_build_msg(&data->ssl, EAP_TYPE_FAST,
869 						data->fast_version, id);
870 	}
871 
872 	switch (data->state) {
873 	case START:
874 		return eap_fast_build_start(sm, data, id);
875 	case PHASE1:
876 		if (tls_connection_established(sm->ssl_ctx, data->ssl.conn)) {
877 			if (eap_fast_phase1_done(sm, data) < 0)
878 				return NULL;
879 			if (data->state == PHASE2_START) {
880 				/*
881 				 * Try to generate Phase 2 data to piggyback
882 				 * with the end of Phase 1 to avoid extra
883 				 * roundtrip.
884 				 */
885 				wpa_printf(MSG_DEBUG, "EAP-FAST: Try to start "
886 					   "Phase 2");
887 				if (eap_fast_process_phase2_start(sm, data))
888 					break;
889 				req = eap_fast_build_phase2_req(sm, data, id);
890 				piggyback = 1;
891 			}
892 		}
893 		break;
894 	case PHASE2_ID:
895 	case PHASE2_METHOD:
896 		req = eap_fast_build_phase2_req(sm, data, id);
897 		break;
898 	case CRYPTO_BINDING:
899 		req = eap_fast_build_crypto_binding(sm, data);
900 		if (data->phase2_method) {
901 			/*
902 			 * Include the start of the next EAP method in the
903 			 * sequence in the same message with Crypto-Binding to
904 			 * save a round-trip.
905 			 */
906 			struct wpabuf *eap;
907 			eap = eap_fast_build_phase2_req(sm, data, id);
908 			req = wpabuf_concat(req, eap);
909 			eap_fast_state(data, PHASE2_METHOD);
910 		}
911 		break;
912 	case REQUEST_PAC:
913 		req = eap_fast_build_pac(sm, data);
914 		break;
915 	default:
916 		wpa_printf(MSG_DEBUG, "EAP-FAST: %s - unexpected state %d",
917 			   __func__, data->state);
918 		return NULL;
919 	}
920 
921 	if (req &&
922 	    eap_fast_encrypt_phase2(sm, data, req, piggyback) < 0)
923 		return NULL;
924 
925 	return eap_server_tls_build_msg(&data->ssl, EAP_TYPE_FAST,
926 					data->fast_version, id);
927 }
928 
929 
eap_fast_check(struct eap_sm * sm,void * priv,struct wpabuf * respData)930 static Boolean eap_fast_check(struct eap_sm *sm, void *priv,
931 			      struct wpabuf *respData)
932 {
933 	const u8 *pos;
934 	size_t len;
935 
936 	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_FAST, respData, &len);
937 	if (pos == NULL || len < 1) {
938 		wpa_printf(MSG_INFO, "EAP-FAST: Invalid frame");
939 		return TRUE;
940 	}
941 
942 	return FALSE;
943 }
944 
945 
eap_fast_phase2_init(struct eap_sm * sm,struct eap_fast_data * data,EapType eap_type)946 static int eap_fast_phase2_init(struct eap_sm *sm, struct eap_fast_data *data,
947 				EapType eap_type)
948 {
949 	if (data->phase2_priv && data->phase2_method) {
950 		data->phase2_method->reset(sm, data->phase2_priv);
951 		data->phase2_method = NULL;
952 		data->phase2_priv = NULL;
953 	}
954 	data->phase2_method = eap_server_get_eap_method(EAP_VENDOR_IETF,
955 							eap_type);
956 	if (!data->phase2_method)
957 		return -1;
958 
959 	if (data->key_block_p) {
960 		sm->auth_challenge = data->key_block_p->server_challenge;
961 		sm->peer_challenge = data->key_block_p->client_challenge;
962 	}
963 	sm->init_phase2 = 1;
964 	data->phase2_priv = data->phase2_method->init(sm);
965 	sm->init_phase2 = 0;
966 	sm->auth_challenge = NULL;
967 	sm->peer_challenge = NULL;
968 
969 	return data->phase2_priv == NULL ? -1 : 0;
970 }
971 
972 
eap_fast_process_phase2_response(struct eap_sm * sm,struct eap_fast_data * data,u8 * in_data,size_t in_len)973 static void eap_fast_process_phase2_response(struct eap_sm *sm,
974 					     struct eap_fast_data *data,
975 					     u8 *in_data, size_t in_len)
976 {
977 	u8 next_type = EAP_TYPE_NONE;
978 	struct eap_hdr *hdr;
979 	u8 *pos;
980 	size_t left;
981 	struct wpabuf buf;
982 	const struct eap_method *m = data->phase2_method;
983 	void *priv = data->phase2_priv;
984 
985 	if (priv == NULL) {
986 		wpa_printf(MSG_DEBUG, "EAP-FAST: %s - Phase2 not "
987 			   "initialized?!", __func__);
988 		return;
989 	}
990 
991 	hdr = (struct eap_hdr *) in_data;
992 	pos = (u8 *) (hdr + 1);
993 
994 	if (in_len > sizeof(*hdr) && *pos == EAP_TYPE_NAK) {
995 		left = in_len - sizeof(*hdr);
996 		wpa_hexdump(MSG_DEBUG, "EAP-FAST: Phase2 type Nak'ed; "
997 			    "allowed types", pos + 1, left - 1);
998 #ifdef EAP_SERVER_TNC
999 		if (m && m->vendor == EAP_VENDOR_IETF &&
1000 		    m->method == EAP_TYPE_TNC) {
1001 			wpa_printf(MSG_DEBUG, "EAP-FAST: Peer Nak'ed required "
1002 				   "TNC negotiation");
1003 			next_type = eap_fast_req_failure(sm, data);
1004 			eap_fast_phase2_init(sm, data, next_type);
1005 			return;
1006 		}
1007 #endif /* EAP_SERVER_TNC */
1008 		eap_sm_process_nak(sm, pos + 1, left - 1);
1009 		if (sm->user && sm->user_eap_method_index < EAP_MAX_METHODS &&
1010 		    sm->user->methods[sm->user_eap_method_index].method !=
1011 		    EAP_TYPE_NONE) {
1012 			next_type = sm->user->methods[
1013 				sm->user_eap_method_index++].method;
1014 			wpa_printf(MSG_DEBUG, "EAP-FAST: try EAP type %d",
1015 				   next_type);
1016 		} else {
1017 			next_type = eap_fast_req_failure(sm, data);
1018 		}
1019 		eap_fast_phase2_init(sm, data, next_type);
1020 		return;
1021 	}
1022 
1023 	wpabuf_set(&buf, in_data, in_len);
1024 
1025 	if (m->check(sm, priv, &buf)) {
1026 		wpa_printf(MSG_DEBUG, "EAP-FAST: Phase2 check() asked to "
1027 			   "ignore the packet");
1028 		eap_fast_req_failure(sm, data);
1029 		return;
1030 	}
1031 
1032 	m->process(sm, priv, &buf);
1033 
1034 	if (!m->isDone(sm, priv))
1035 		return;
1036 
1037 	if (!m->isSuccess(sm, priv)) {
1038 		wpa_printf(MSG_DEBUG, "EAP-FAST: Phase2 method failed");
1039 		next_type = eap_fast_req_failure(sm, data);
1040 		eap_fast_phase2_init(sm, data, next_type);
1041 		return;
1042 	}
1043 
1044 	switch (data->state) {
1045 	case PHASE2_ID:
1046 		if (eap_user_get(sm, sm->identity, sm->identity_len, 1) != 0) {
1047 			wpa_hexdump_ascii(MSG_DEBUG, "EAP-FAST: Phase2 "
1048 					  "Identity not found in the user "
1049 					  "database",
1050 					  sm->identity, sm->identity_len);
1051 			next_type = eap_fast_req_failure(sm, data);
1052 			break;
1053 		}
1054 
1055 		eap_fast_state(data, PHASE2_METHOD);
1056 		if (data->anon_provisioning) {
1057 			/*
1058 			 * Only EAP-MSCHAPv2 is allowed for anonymous
1059 			 * provisioning.
1060 			 */
1061 			next_type = EAP_TYPE_MSCHAPV2;
1062 			sm->user_eap_method_index = 0;
1063 		} else {
1064 			next_type = sm->user->methods[0].method;
1065 			sm->user_eap_method_index = 1;
1066 		}
1067 		wpa_printf(MSG_DEBUG, "EAP-FAST: try EAP type %d", next_type);
1068 		break;
1069 	case PHASE2_METHOD:
1070 	case CRYPTO_BINDING:
1071 		eap_fast_update_icmk(sm, data);
1072 		eap_fast_state(data, CRYPTO_BINDING);
1073 		data->eap_seq++;
1074 		next_type = EAP_TYPE_NONE;
1075 #ifdef EAP_SERVER_TNC
1076 		if (sm->tnc && !data->tnc_started) {
1077 			wpa_printf(MSG_DEBUG, "EAP-FAST: Initialize TNC");
1078 			next_type = EAP_TYPE_TNC;
1079 			data->tnc_started = 1;
1080 		}
1081 #endif /* EAP_SERVER_TNC */
1082 		break;
1083 	case FAILURE:
1084 		break;
1085 	default:
1086 		wpa_printf(MSG_DEBUG, "EAP-FAST: %s - unexpected state %d",
1087 			   __func__, data->state);
1088 		break;
1089 	}
1090 
1091 	eap_fast_phase2_init(sm, data, next_type);
1092 }
1093 
1094 
eap_fast_process_phase2_eap(struct eap_sm * sm,struct eap_fast_data * data,u8 * in_data,size_t in_len)1095 static void eap_fast_process_phase2_eap(struct eap_sm *sm,
1096 					struct eap_fast_data *data,
1097 					u8 *in_data, size_t in_len)
1098 {
1099 	struct eap_hdr *hdr;
1100 	size_t len;
1101 
1102 	hdr = (struct eap_hdr *) in_data;
1103 	if (in_len < (int) sizeof(*hdr)) {
1104 		wpa_printf(MSG_INFO, "EAP-FAST: Too short Phase 2 "
1105 			   "EAP frame (len=%lu)", (unsigned long) in_len);
1106 		eap_fast_req_failure(sm, data);
1107 		return;
1108 	}
1109 	len = be_to_host16(hdr->length);
1110 	if (len > in_len) {
1111 		wpa_printf(MSG_INFO, "EAP-FAST: Length mismatch in "
1112 			   "Phase 2 EAP frame (len=%lu hdr->length=%lu)",
1113 			   (unsigned long) in_len, (unsigned long) len);
1114 		eap_fast_req_failure(sm, data);
1115 		return;
1116 	}
1117 	wpa_printf(MSG_DEBUG, "EAP-FAST: Received Phase 2: code=%d "
1118 		   "identifier=%d length=%lu", hdr->code, hdr->identifier,
1119 		   (unsigned long) len);
1120 	switch (hdr->code) {
1121 	case EAP_CODE_RESPONSE:
1122 		eap_fast_process_phase2_response(sm, data, (u8 *) hdr, len);
1123 		break;
1124 	default:
1125 		wpa_printf(MSG_INFO, "EAP-FAST: Unexpected code=%d in "
1126 			   "Phase 2 EAP header", hdr->code);
1127 		break;
1128 	}
1129 }
1130 
1131 
eap_fast_parse_tlvs(struct wpabuf * data,struct eap_fast_tlv_parse * tlv)1132 static int eap_fast_parse_tlvs(struct wpabuf *data,
1133 			       struct eap_fast_tlv_parse *tlv)
1134 {
1135 	int mandatory, tlv_type, res;
1136 	size_t len;
1137 	u8 *pos, *end;
1138 
1139 	os_memset(tlv, 0, sizeof(*tlv));
1140 
1141 	pos = wpabuf_mhead(data);
1142 	end = pos + wpabuf_len(data);
1143 	while (end - pos > 4) {
1144 		mandatory = pos[0] & 0x80;
1145 		tlv_type = WPA_GET_BE16(pos) & 0x3fff;
1146 		pos += 2;
1147 		len = WPA_GET_BE16(pos);
1148 		pos += 2;
1149 		if (len > (size_t) (end - pos)) {
1150 			wpa_printf(MSG_INFO, "EAP-FAST: TLV overflow");
1151 			return -1;
1152 		}
1153 		wpa_printf(MSG_DEBUG, "EAP-FAST: Received Phase 2: "
1154 			   "TLV type %d length %u%s",
1155 			   tlv_type, (unsigned int) len,
1156 			   mandatory ? " (mandatory)" : "");
1157 
1158 		res = eap_fast_parse_tlv(tlv, tlv_type, pos, len);
1159 		if (res == -2)
1160 			break;
1161 		if (res < 0) {
1162 			if (mandatory) {
1163 				wpa_printf(MSG_DEBUG, "EAP-FAST: Nak unknown "
1164 					   "mandatory TLV type %d", tlv_type);
1165 				/* TODO: generate Nak TLV */
1166 				break;
1167 			} else {
1168 				wpa_printf(MSG_DEBUG, "EAP-FAST: Ignored "
1169 					   "unknown optional TLV type %d",
1170 					   tlv_type);
1171 			}
1172 		}
1173 
1174 		pos += len;
1175 	}
1176 
1177 	return 0;
1178 }
1179 
1180 
eap_fast_validate_crypto_binding(struct eap_fast_data * data,struct eap_tlv_crypto_binding_tlv * b,size_t bind_len)1181 static int eap_fast_validate_crypto_binding(
1182 	struct eap_fast_data *data, struct eap_tlv_crypto_binding_tlv *b,
1183 	size_t bind_len)
1184 {
1185 	u8 cmac[SHA1_MAC_LEN];
1186 
1187 	wpa_printf(MSG_DEBUG, "EAP-FAST: Reply Crypto-Binding TLV: "
1188 		   "Version %d Received Version %d SubType %d",
1189 		   b->version, b->received_version, b->subtype);
1190 	wpa_hexdump(MSG_MSGDUMP, "EAP-FAST: NONCE",
1191 		    b->nonce, sizeof(b->nonce));
1192 	wpa_hexdump(MSG_MSGDUMP, "EAP-FAST: Compound MAC",
1193 		    b->compound_mac, sizeof(b->compound_mac));
1194 
1195 	if (b->version != EAP_FAST_VERSION ||
1196 	    b->received_version != EAP_FAST_VERSION) {
1197 		wpa_printf(MSG_DEBUG, "EAP-FAST: Unexpected version "
1198 			   "in Crypto-Binding: version %d "
1199 			   "received_version %d", b->version,
1200 			   b->received_version);
1201 		return -1;
1202 	}
1203 
1204 	if (b->subtype != EAP_TLV_CRYPTO_BINDING_SUBTYPE_RESPONSE) {
1205 		wpa_printf(MSG_DEBUG, "EAP-FAST: Unexpected subtype in "
1206 			   "Crypto-Binding: %d", b->subtype);
1207 		return -1;
1208 	}
1209 
1210 	if (os_memcmp_const(data->crypto_binding_nonce, b->nonce, 31) != 0 ||
1211 	    (data->crypto_binding_nonce[31] | 1) != b->nonce[31]) {
1212 		wpa_printf(MSG_DEBUG, "EAP-FAST: Invalid nonce in "
1213 			   "Crypto-Binding");
1214 		return -1;
1215 	}
1216 
1217 	os_memcpy(cmac, b->compound_mac, sizeof(cmac));
1218 	os_memset(b->compound_mac, 0, sizeof(cmac));
1219 	wpa_hexdump(MSG_MSGDUMP, "EAP-FAST: Crypto-Binding TLV for "
1220 		    "Compound MAC calculation",
1221 		    (u8 *) b, bind_len);
1222 	hmac_sha1(data->cmk, EAP_FAST_CMK_LEN, (u8 *) b, bind_len,
1223 		  b->compound_mac);
1224 	if (os_memcmp_const(cmac, b->compound_mac, sizeof(cmac)) != 0) {
1225 		wpa_hexdump(MSG_MSGDUMP,
1226 			    "EAP-FAST: Calculated Compound MAC",
1227 			    b->compound_mac, sizeof(cmac));
1228 		wpa_printf(MSG_INFO, "EAP-FAST: Compound MAC did not "
1229 			   "match");
1230 		return -1;
1231 	}
1232 
1233 	return 0;
1234 }
1235 
1236 
eap_fast_pac_type(u8 * pac,size_t len,u16 type)1237 static int eap_fast_pac_type(u8 *pac, size_t len, u16 type)
1238 {
1239 	struct eap_tlv_pac_type_tlv *tlv;
1240 
1241 	if (pac == NULL || len != sizeof(*tlv))
1242 		return 0;
1243 
1244 	tlv = (struct eap_tlv_pac_type_tlv *) pac;
1245 
1246 	return be_to_host16(tlv->tlv_type) == PAC_TYPE_PAC_TYPE &&
1247 		be_to_host16(tlv->length) == 2 &&
1248 		be_to_host16(tlv->pac_type) == type;
1249 }
1250 
1251 
eap_fast_process_phase2_tlvs(struct eap_sm * sm,struct eap_fast_data * data,struct wpabuf * in_data)1252 static void eap_fast_process_phase2_tlvs(struct eap_sm *sm,
1253 					 struct eap_fast_data *data,
1254 					 struct wpabuf *in_data)
1255 {
1256 	struct eap_fast_tlv_parse tlv;
1257 	int check_crypto_binding = data->state == CRYPTO_BINDING;
1258 
1259 	if (eap_fast_parse_tlvs(in_data, &tlv) < 0) {
1260 		wpa_printf(MSG_DEBUG, "EAP-FAST: Failed to parse received "
1261 			   "Phase 2 TLVs");
1262 		return;
1263 	}
1264 
1265 	if (tlv.result == EAP_TLV_RESULT_FAILURE) {
1266 		wpa_printf(MSG_DEBUG, "EAP-FAST: Result TLV indicated "
1267 			   "failure");
1268 		eap_fast_state(data, FAILURE);
1269 		return;
1270 	}
1271 
1272 	if (data->state == REQUEST_PAC) {
1273 		u16 type, len, res;
1274 		if (tlv.pac == NULL || tlv.pac_len < 6) {
1275 			wpa_printf(MSG_DEBUG, "EAP-FAST: No PAC "
1276 				   "Acknowledgement received");
1277 			eap_fast_state(data, FAILURE);
1278 			return;
1279 		}
1280 
1281 		type = WPA_GET_BE16(tlv.pac);
1282 		len = WPA_GET_BE16(tlv.pac + 2);
1283 		res = WPA_GET_BE16(tlv.pac + 4);
1284 
1285 		if (type != PAC_TYPE_PAC_ACKNOWLEDGEMENT || len != 2 ||
1286 		    res != EAP_TLV_RESULT_SUCCESS) {
1287 			wpa_printf(MSG_DEBUG, "EAP-FAST: PAC TLV did not "
1288 				   "contain acknowledgement");
1289 			eap_fast_state(data, FAILURE);
1290 			return;
1291 		}
1292 
1293 		wpa_printf(MSG_DEBUG, "EAP-FAST: PAC-Acknowledgement received "
1294 			   "- PAC provisioning succeeded");
1295 		eap_fast_state(data, (data->anon_provisioning ||
1296 				      data->send_new_pac == 2) ?
1297 			       FAILURE : SUCCESS);
1298 		return;
1299 	}
1300 
1301 	if (check_crypto_binding) {
1302 		if (tlv.crypto_binding == NULL) {
1303 			wpa_printf(MSG_DEBUG, "EAP-FAST: No Crypto-Binding "
1304 				   "TLV received");
1305 			eap_fast_state(data, FAILURE);
1306 			return;
1307 		}
1308 
1309 		if (data->final_result &&
1310 		    tlv.result != EAP_TLV_RESULT_SUCCESS) {
1311 			wpa_printf(MSG_DEBUG, "EAP-FAST: Crypto-Binding TLV "
1312 				   "without Success Result");
1313 			eap_fast_state(data, FAILURE);
1314 			return;
1315 		}
1316 
1317 		if (!data->final_result &&
1318 		    tlv.iresult != EAP_TLV_RESULT_SUCCESS) {
1319 			wpa_printf(MSG_DEBUG, "EAP-FAST: Crypto-Binding TLV "
1320 				   "without intermediate Success Result");
1321 			eap_fast_state(data, FAILURE);
1322 			return;
1323 		}
1324 
1325 		if (eap_fast_validate_crypto_binding(data, tlv.crypto_binding,
1326 						     tlv.crypto_binding_len)) {
1327 			eap_fast_state(data, FAILURE);
1328 			return;
1329 		}
1330 
1331 		wpa_printf(MSG_DEBUG, "EAP-FAST: Valid Crypto-Binding TLV "
1332 			   "received");
1333 		if (data->final_result) {
1334 			wpa_printf(MSG_DEBUG, "EAP-FAST: Authentication "
1335 				   "completed successfully");
1336 		}
1337 
1338 		if (data->anon_provisioning &&
1339 		    sm->eap_fast_prov != ANON_PROV &&
1340 		    sm->eap_fast_prov != BOTH_PROV) {
1341 			wpa_printf(MSG_DEBUG, "EAP-FAST: Client is trying to "
1342 				   "use unauthenticated provisioning which is "
1343 				   "disabled");
1344 			eap_fast_state(data, FAILURE);
1345 			return;
1346 		}
1347 
1348 		if (sm->eap_fast_prov != AUTH_PROV &&
1349 		    sm->eap_fast_prov != BOTH_PROV &&
1350 		    tlv.request_action == EAP_TLV_ACTION_PROCESS_TLV &&
1351 		    eap_fast_pac_type(tlv.pac, tlv.pac_len,
1352 				      PAC_TYPE_TUNNEL_PAC)) {
1353 			wpa_printf(MSG_DEBUG, "EAP-FAST: Client is trying to "
1354 				   "use authenticated provisioning which is "
1355 				   "disabled");
1356 			eap_fast_state(data, FAILURE);
1357 			return;
1358 		}
1359 
1360 		if (data->anon_provisioning ||
1361 		    (tlv.request_action == EAP_TLV_ACTION_PROCESS_TLV &&
1362 		     eap_fast_pac_type(tlv.pac, tlv.pac_len,
1363 				       PAC_TYPE_TUNNEL_PAC))) {
1364 			wpa_printf(MSG_DEBUG, "EAP-FAST: Requested a new "
1365 				   "Tunnel PAC");
1366 			eap_fast_state(data, REQUEST_PAC);
1367 		} else if (data->send_new_pac) {
1368 			wpa_printf(MSG_DEBUG, "EAP-FAST: Server triggered "
1369 				   "re-keying of Tunnel PAC");
1370 			eap_fast_state(data, REQUEST_PAC);
1371 		} else if (data->final_result)
1372 			eap_fast_state(data, SUCCESS);
1373 	}
1374 
1375 	if (tlv.eap_payload_tlv) {
1376 		eap_fast_process_phase2_eap(sm, data, tlv.eap_payload_tlv,
1377 					    tlv.eap_payload_tlv_len);
1378 	}
1379 }
1380 
1381 
eap_fast_process_phase2(struct eap_sm * sm,struct eap_fast_data * data,struct wpabuf * in_buf)1382 static void eap_fast_process_phase2(struct eap_sm *sm,
1383 				    struct eap_fast_data *data,
1384 				    struct wpabuf *in_buf)
1385 {
1386 	struct wpabuf *in_decrypted;
1387 
1388 	wpa_printf(MSG_DEBUG, "EAP-FAST: Received %lu bytes encrypted data for"
1389 		   " Phase 2", (unsigned long) wpabuf_len(in_buf));
1390 
1391 	if (data->pending_phase2_resp) {
1392 		wpa_printf(MSG_DEBUG, "EAP-PEAP: Pending Phase 2 response - "
1393 			   "skip decryption and use old data");
1394 		eap_fast_process_phase2_tlvs(sm, data,
1395 					     data->pending_phase2_resp);
1396 		wpabuf_free(data->pending_phase2_resp);
1397 		data->pending_phase2_resp = NULL;
1398 		return;
1399 	}
1400 
1401 	in_decrypted = tls_connection_decrypt(sm->ssl_ctx, data->ssl.conn,
1402 					      in_buf);
1403 	if (in_decrypted == NULL) {
1404 		wpa_printf(MSG_INFO, "EAP-FAST: Failed to decrypt Phase 2 "
1405 			   "data");
1406 		eap_fast_state(data, FAILURE);
1407 		return;
1408 	}
1409 
1410 	wpa_hexdump_buf_key(MSG_DEBUG, "EAP-FAST: Decrypted Phase 2 TLVs",
1411 			    in_decrypted);
1412 
1413 	eap_fast_process_phase2_tlvs(sm, data, in_decrypted);
1414 
1415 	if (sm->method_pending == METHOD_PENDING_WAIT) {
1416 		wpa_printf(MSG_DEBUG, "EAP-FAST: Phase2 method is in "
1417 			   "pending wait state - save decrypted response");
1418 		wpabuf_free(data->pending_phase2_resp);
1419 		data->pending_phase2_resp = in_decrypted;
1420 		return;
1421 	}
1422 
1423 	wpabuf_free(in_decrypted);
1424 }
1425 
1426 
eap_fast_process_version(struct eap_sm * sm,void * priv,int peer_version)1427 static int eap_fast_process_version(struct eap_sm *sm, void *priv,
1428 				    int peer_version)
1429 {
1430 	struct eap_fast_data *data = priv;
1431 
1432 	data->peer_version = peer_version;
1433 
1434 	if (data->force_version >= 0 && peer_version != data->force_version) {
1435 		wpa_printf(MSG_INFO, "EAP-FAST: peer did not select the forced"
1436 			   " version (forced=%d peer=%d) - reject",
1437 			   data->force_version, peer_version);
1438 		return -1;
1439 	}
1440 
1441 	if (peer_version < data->fast_version) {
1442 		wpa_printf(MSG_DEBUG, "EAP-FAST: peer ver=%d, own ver=%d; "
1443 			   "use version %d",
1444 			   peer_version, data->fast_version, peer_version);
1445 		data->fast_version = peer_version;
1446 	}
1447 
1448 	return 0;
1449 }
1450 
1451 
eap_fast_process_phase1(struct eap_sm * sm,struct eap_fast_data * data)1452 static int eap_fast_process_phase1(struct eap_sm *sm,
1453 				   struct eap_fast_data *data)
1454 {
1455 	if (eap_server_tls_phase1(sm, &data->ssl) < 0) {
1456 		wpa_printf(MSG_INFO, "EAP-FAST: TLS processing failed");
1457 		eap_fast_state(data, FAILURE);
1458 		return -1;
1459 	}
1460 
1461 	if (!tls_connection_established(sm->ssl_ctx, data->ssl.conn) ||
1462 	    wpabuf_len(data->ssl.tls_out) > 0)
1463 		return 1;
1464 
1465 	/*
1466 	 * Phase 1 was completed with the received message (e.g., when using
1467 	 * abbreviated handshake), so Phase 2 can be started immediately
1468 	 * without having to send through an empty message to the peer.
1469 	 */
1470 
1471 	return eap_fast_phase1_done(sm, data);
1472 }
1473 
1474 
eap_fast_process_phase2_start(struct eap_sm * sm,struct eap_fast_data * data)1475 static int eap_fast_process_phase2_start(struct eap_sm *sm,
1476 					 struct eap_fast_data *data)
1477 {
1478 	u8 next_type;
1479 
1480 	if (data->identity) {
1481 		os_free(sm->identity);
1482 		sm->identity = data->identity;
1483 		data->identity = NULL;
1484 		sm->identity_len = data->identity_len;
1485 		data->identity_len = 0;
1486 		sm->require_identity_match = 1;
1487 		if (eap_user_get(sm, sm->identity, sm->identity_len, 1) != 0) {
1488 			wpa_hexdump_ascii(MSG_DEBUG, "EAP-FAST: "
1489 					  "Phase2 Identity not found "
1490 					  "in the user database",
1491 					  sm->identity, sm->identity_len);
1492 			next_type = eap_fast_req_failure(sm, data);
1493 		} else {
1494 			wpa_printf(MSG_DEBUG, "EAP-FAST: Identity already "
1495 				   "known - skip Phase 2 Identity Request");
1496 			next_type = sm->user->methods[0].method;
1497 			sm->user_eap_method_index = 1;
1498 		}
1499 
1500 		eap_fast_state(data, PHASE2_METHOD);
1501 	} else {
1502 		eap_fast_state(data, PHASE2_ID);
1503 		next_type = EAP_TYPE_IDENTITY;
1504 	}
1505 
1506 	return eap_fast_phase2_init(sm, data, next_type);
1507 }
1508 
1509 
eap_fast_process_msg(struct eap_sm * sm,void * priv,const struct wpabuf * respData)1510 static void eap_fast_process_msg(struct eap_sm *sm, void *priv,
1511 				 const struct wpabuf *respData)
1512 {
1513 	struct eap_fast_data *data = priv;
1514 
1515 	switch (data->state) {
1516 	case PHASE1:
1517 		if (eap_fast_process_phase1(sm, data))
1518 			break;
1519 
1520 		/* fall through to PHASE2_START */
1521 	case PHASE2_START:
1522 		eap_fast_process_phase2_start(sm, data);
1523 		break;
1524 	case PHASE2_ID:
1525 	case PHASE2_METHOD:
1526 	case CRYPTO_BINDING:
1527 	case REQUEST_PAC:
1528 		eap_fast_process_phase2(sm, data, data->ssl.tls_in);
1529 		break;
1530 	default:
1531 		wpa_printf(MSG_DEBUG, "EAP-FAST: Unexpected state %d in %s",
1532 			   data->state, __func__);
1533 		break;
1534 	}
1535 }
1536 
1537 
eap_fast_process(struct eap_sm * sm,void * priv,struct wpabuf * respData)1538 static void eap_fast_process(struct eap_sm *sm, void *priv,
1539 			     struct wpabuf *respData)
1540 {
1541 	struct eap_fast_data *data = priv;
1542 	if (eap_server_tls_process(sm, &data->ssl, respData, data,
1543 				   EAP_TYPE_FAST, eap_fast_process_version,
1544 				   eap_fast_process_msg) < 0)
1545 		eap_fast_state(data, FAILURE);
1546 }
1547 
1548 
eap_fast_isDone(struct eap_sm * sm,void * priv)1549 static Boolean eap_fast_isDone(struct eap_sm *sm, void *priv)
1550 {
1551 	struct eap_fast_data *data = priv;
1552 	return data->state == SUCCESS || data->state == FAILURE;
1553 }
1554 
1555 
eap_fast_getKey(struct eap_sm * sm,void * priv,size_t * len)1556 static u8 * eap_fast_getKey(struct eap_sm *sm, void *priv, size_t *len)
1557 {
1558 	struct eap_fast_data *data = priv;
1559 	u8 *eapKeyData;
1560 
1561 	if (data->state != SUCCESS)
1562 		return NULL;
1563 
1564 	eapKeyData = os_malloc(EAP_FAST_KEY_LEN);
1565 	if (eapKeyData == NULL)
1566 		return NULL;
1567 
1568 	if (eap_fast_derive_eap_msk(data->simck, eapKeyData) < 0) {
1569 		os_free(eapKeyData);
1570 		return NULL;
1571 	}
1572 	*len = EAP_FAST_KEY_LEN;
1573 
1574 	return eapKeyData;
1575 }
1576 
1577 
eap_fast_get_emsk(struct eap_sm * sm,void * priv,size_t * len)1578 static u8 * eap_fast_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1579 {
1580 	struct eap_fast_data *data = priv;
1581 	u8 *eapKeyData;
1582 
1583 	if (data->state != SUCCESS)
1584 		return NULL;
1585 
1586 	eapKeyData = os_malloc(EAP_EMSK_LEN);
1587 	if (eapKeyData == NULL)
1588 		return NULL;
1589 
1590 	if (eap_fast_derive_eap_emsk(data->simck, eapKeyData) < 0) {
1591 		os_free(eapKeyData);
1592 		return NULL;
1593 	}
1594 	*len = EAP_EMSK_LEN;
1595 
1596 	return eapKeyData;
1597 }
1598 
1599 
eap_fast_isSuccess(struct eap_sm * sm,void * priv)1600 static Boolean eap_fast_isSuccess(struct eap_sm *sm, void *priv)
1601 {
1602 	struct eap_fast_data *data = priv;
1603 	return data->state == SUCCESS;
1604 }
1605 
1606 
eap_fast_get_session_id(struct eap_sm * sm,void * priv,size_t * len)1607 static u8 * eap_fast_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1608 {
1609 	struct eap_fast_data *data = priv;
1610 
1611 	if (data->state != SUCCESS)
1612 		return NULL;
1613 
1614 	return eap_server_tls_derive_session_id(sm, &data->ssl, EAP_TYPE_FAST,
1615 						len);
1616 }
1617 
1618 
eap_server_fast_register(void)1619 int eap_server_fast_register(void)
1620 {
1621 	struct eap_method *eap;
1622 
1623 	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
1624 				      EAP_VENDOR_IETF, EAP_TYPE_FAST, "FAST");
1625 	if (eap == NULL)
1626 		return -1;
1627 
1628 	eap->init = eap_fast_init;
1629 	eap->reset = eap_fast_reset;
1630 	eap->buildReq = eap_fast_buildReq;
1631 	eap->check = eap_fast_check;
1632 	eap->process = eap_fast_process;
1633 	eap->isDone = eap_fast_isDone;
1634 	eap->getKey = eap_fast_getKey;
1635 	eap->get_emsk = eap_fast_get_emsk;
1636 	eap->isSuccess = eap_fast_isSuccess;
1637 	eap->getSessionId = eap_fast_get_session_id;
1638 
1639 	return eap_server_method_register(eap);
1640 }
1641