1 /*
2 * EAP peer: EAP-TLS/PEAP/TTLS/FAST common functions
3 * Copyright (c) 2004-2013, 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/sha1.h"
13 #include "crypto/tls.h"
14 #include "eap_i.h"
15 #include "eap_tls_common.h"
16 #include "eap_config.h"
17
18
eap_tls_msg_alloc(EapType type,size_t payload_len,u8 code,u8 identifier)19 static struct wpabuf * eap_tls_msg_alloc(EapType type, size_t payload_len,
20 u8 code, u8 identifier)
21 {
22 if (type == EAP_UNAUTH_TLS_TYPE)
23 return eap_msg_alloc(EAP_VENDOR_UNAUTH_TLS,
24 EAP_VENDOR_TYPE_UNAUTH_TLS, payload_len,
25 code, identifier);
26 return eap_msg_alloc(EAP_VENDOR_IETF, type, payload_len, code,
27 identifier);
28 }
29
30
eap_tls_check_blob(struct eap_sm * sm,const char ** name,const u8 ** data,size_t * data_len)31 static int eap_tls_check_blob(struct eap_sm *sm, const char **name,
32 const u8 **data, size_t *data_len)
33 {
34 const struct wpa_config_blob *blob;
35
36 if (*name == NULL || os_strncmp(*name, "blob://", 7) != 0)
37 return 0;
38
39 blob = eap_get_config_blob(sm, *name + 7);
40 if (blob == NULL) {
41 wpa_printf(MSG_ERROR, "%s: Named configuration blob '%s' not "
42 "found", __func__, *name + 7);
43 return -1;
44 }
45
46 *name = NULL;
47 *data = blob->data;
48 *data_len = blob->len;
49
50 return 0;
51 }
52
53
eap_tls_params_flags(struct tls_connection_params * params,const char * txt)54 static void eap_tls_params_flags(struct tls_connection_params *params,
55 const char *txt)
56 {
57 if (txt == NULL)
58 return;
59 if (os_strstr(txt, "tls_allow_md5=1"))
60 params->flags |= TLS_CONN_ALLOW_SIGN_RSA_MD5;
61 if (os_strstr(txt, "tls_disable_time_checks=1"))
62 params->flags |= TLS_CONN_DISABLE_TIME_CHECKS;
63 if (os_strstr(txt, "tls_disable_session_ticket=1"))
64 params->flags |= TLS_CONN_DISABLE_SESSION_TICKET;
65 if (os_strstr(txt, "tls_disable_session_ticket=0"))
66 params->flags &= ~TLS_CONN_DISABLE_SESSION_TICKET;
67 }
68
69
eap_tls_params_from_conf1(struct tls_connection_params * params,struct eap_peer_config * config)70 static void eap_tls_params_from_conf1(struct tls_connection_params *params,
71 struct eap_peer_config *config)
72 {
73 params->ca_cert = (char *) config->ca_cert;
74 params->ca_path = (char *) config->ca_path;
75 params->client_cert = (char *) config->client_cert;
76 params->private_key = (char *) config->private_key;
77 params->private_key_passwd = (char *) config->private_key_passwd;
78 params->dh_file = (char *) config->dh_file;
79 params->subject_match = (char *) config->subject_match;
80 params->altsubject_match = (char *) config->altsubject_match;
81 params->engine = config->engine;
82 params->engine_id = config->engine_id;
83 params->pin = config->pin;
84 params->key_id = config->key_id;
85 params->cert_id = config->cert_id;
86 params->ca_cert_id = config->ca_cert_id;
87 eap_tls_params_flags(params, config->phase1);
88 }
89
90
eap_tls_params_from_conf2(struct tls_connection_params * params,struct eap_peer_config * config)91 static void eap_tls_params_from_conf2(struct tls_connection_params *params,
92 struct eap_peer_config *config)
93 {
94 params->ca_cert = (char *) config->ca_cert2;
95 params->ca_path = (char *) config->ca_path2;
96 params->client_cert = (char *) config->client_cert2;
97 params->private_key = (char *) config->private_key2;
98 params->private_key_passwd = (char *) config->private_key2_passwd;
99 params->dh_file = (char *) config->dh_file2;
100 params->subject_match = (char *) config->subject_match2;
101 params->altsubject_match = (char *) config->altsubject_match2;
102 params->engine = config->engine2;
103 params->engine_id = config->engine2_id;
104 params->pin = config->pin2;
105 params->key_id = config->key2_id;
106 params->cert_id = config->cert2_id;
107 params->ca_cert_id = config->ca_cert2_id;
108 eap_tls_params_flags(params, config->phase2);
109 }
110
111
eap_tls_params_from_conf(struct eap_sm * sm,struct eap_ssl_data * data,struct tls_connection_params * params,struct eap_peer_config * config,int phase2)112 static int eap_tls_params_from_conf(struct eap_sm *sm,
113 struct eap_ssl_data *data,
114 struct tls_connection_params *params,
115 struct eap_peer_config *config, int phase2)
116 {
117 os_memset(params, 0, sizeof(*params));
118 if (sm->workaround && data->eap_type != EAP_TYPE_FAST) {
119 /*
120 * Some deployed authentication servers seem to be unable to
121 * handle the TLS Session Ticket extension (they are supposed
122 * to ignore unrecognized TLS extensions, but end up rejecting
123 * the ClientHello instead). As a workaround, disable use of
124 * TLS Sesson Ticket extension for EAP-TLS, EAP-PEAP, and
125 * EAP-TTLS (EAP-FAST uses session ticket, so any server that
126 * supports EAP-FAST does not need this workaround).
127 */
128 params->flags |= TLS_CONN_DISABLE_SESSION_TICKET;
129 }
130 if (phase2) {
131 wpa_printf(MSG_DEBUG, "TLS: using phase2 config options");
132 eap_tls_params_from_conf2(params, config);
133 } else {
134 wpa_printf(MSG_DEBUG, "TLS: using phase1 config options");
135 eap_tls_params_from_conf1(params, config);
136 }
137
138 /*
139 * Use blob data, if available. Otherwise, leave reference to external
140 * file as-is.
141 */
142 if (eap_tls_check_blob(sm, ¶ms->ca_cert, ¶ms->ca_cert_blob,
143 ¶ms->ca_cert_blob_len) ||
144 eap_tls_check_blob(sm, ¶ms->client_cert,
145 ¶ms->client_cert_blob,
146 ¶ms->client_cert_blob_len) ||
147 eap_tls_check_blob(sm, ¶ms->private_key,
148 ¶ms->private_key_blob,
149 ¶ms->private_key_blob_len) ||
150 eap_tls_check_blob(sm, ¶ms->dh_file, ¶ms->dh_blob,
151 ¶ms->dh_blob_len)) {
152 wpa_printf(MSG_INFO, "SSL: Failed to get configuration blobs");
153 return -1;
154 }
155
156 return 0;
157 }
158
159
eap_tls_init_connection(struct eap_sm * sm,struct eap_ssl_data * data,struct eap_peer_config * config,struct tls_connection_params * params)160 static int eap_tls_init_connection(struct eap_sm *sm,
161 struct eap_ssl_data *data,
162 struct eap_peer_config *config,
163 struct tls_connection_params *params)
164 {
165 int res;
166
167 if (config->ocsp)
168 params->flags |= TLS_CONN_REQUEST_OCSP;
169 if (config->ocsp == 2)
170 params->flags |= TLS_CONN_REQUIRE_OCSP;
171 data->conn = tls_connection_init(data->ssl_ctx);
172 if (data->conn == NULL) {
173 wpa_printf(MSG_INFO, "SSL: Failed to initialize new TLS "
174 "connection");
175 return -1;
176 }
177
178 res = tls_connection_set_params(data->ssl_ctx, data->conn, params);
179 if (res == TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED) {
180 /*
181 * At this point with the pkcs11 engine the PIN might be wrong.
182 * We reset the PIN in the configuration to be sure to not use
183 * it again and the calling function must request a new one.
184 */
185 os_free(config->pin);
186 config->pin = NULL;
187 } else if (res == TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED) {
188 wpa_printf(MSG_INFO, "TLS: Failed to load private key");
189 /*
190 * We do not know exactly but maybe the PIN was wrong,
191 * so ask for a new one.
192 */
193 os_free(config->pin);
194 config->pin = NULL;
195 eap_sm_request_pin(sm);
196 sm->ignore = TRUE;
197 tls_connection_deinit(data->ssl_ctx, data->conn);
198 data->conn = NULL;
199 return -1;
200 } else if (res) {
201 wpa_printf(MSG_INFO, "TLS: Failed to set TLS connection "
202 "parameters");
203 tls_connection_deinit(data->ssl_ctx, data->conn);
204 data->conn = NULL;
205 return -1;
206 }
207
208 return 0;
209 }
210
211
212 /**
213 * eap_peer_tls_ssl_init - Initialize shared TLS functionality
214 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
215 * @data: Data for TLS processing
216 * @config: Pointer to the network configuration
217 * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
218 * Returns: 0 on success, -1 on failure
219 *
220 * This function is used to initialize shared TLS functionality for EAP-TLS,
221 * EAP-PEAP, EAP-TTLS, and EAP-FAST.
222 */
eap_peer_tls_ssl_init(struct eap_sm * sm,struct eap_ssl_data * data,struct eap_peer_config * config,u8 eap_type)223 int eap_peer_tls_ssl_init(struct eap_sm *sm, struct eap_ssl_data *data,
224 struct eap_peer_config *config, u8 eap_type)
225 {
226 struct tls_connection_params params;
227
228 if (config == NULL)
229 return -1;
230
231 data->eap = sm;
232 data->eap_type = eap_type;
233 data->phase2 = sm->init_phase2;
234 data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
235 sm->ssl_ctx;
236 if (eap_tls_params_from_conf(sm, data, ¶ms, config, data->phase2) <
237 0)
238 return -1;
239
240 if (eap_tls_init_connection(sm, data, config, ¶ms) < 0)
241 return -1;
242
243 data->tls_out_limit = config->fragment_size;
244 if (data->phase2) {
245 /* Limit the fragment size in the inner TLS authentication
246 * since the outer authentication with EAP-PEAP does not yet
247 * support fragmentation */
248 if (data->tls_out_limit > 100)
249 data->tls_out_limit -= 100;
250 }
251
252 if (config->phase1 &&
253 os_strstr(config->phase1, "include_tls_length=1")) {
254 wpa_printf(MSG_DEBUG, "TLS: Include TLS Message Length in "
255 "unfragmented packets");
256 data->include_tls_length = 1;
257 }
258
259 return 0;
260 }
261
262
263 /**
264 * eap_peer_tls_ssl_deinit - Deinitialize shared TLS functionality
265 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
266 * @data: Data for TLS processing
267 *
268 * This function deinitializes shared TLS functionality that was initialized
269 * with eap_peer_tls_ssl_init().
270 */
eap_peer_tls_ssl_deinit(struct eap_sm * sm,struct eap_ssl_data * data)271 void eap_peer_tls_ssl_deinit(struct eap_sm *sm, struct eap_ssl_data *data)
272 {
273 tls_connection_deinit(data->ssl_ctx, data->conn);
274 eap_peer_tls_reset_input(data);
275 eap_peer_tls_reset_output(data);
276 }
277
278
279 /**
280 * eap_peer_tls_derive_key - Derive a key based on TLS session data
281 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
282 * @data: Data for TLS processing
283 * @label: Label string for deriving the keys, e.g., "client EAP encryption"
284 * @len: Length of the key material to generate (usually 64 for MSK)
285 * Returns: Pointer to allocated key on success or %NULL on failure
286 *
287 * This function uses TLS-PRF to generate pseudo-random data based on the TLS
288 * session data (client/server random and master key). Each key type may use a
289 * different label to bind the key usage into the generated material.
290 *
291 * The caller is responsible for freeing the returned buffer.
292 */
eap_peer_tls_derive_key(struct eap_sm * sm,struct eap_ssl_data * data,const char * label,size_t len)293 u8 * eap_peer_tls_derive_key(struct eap_sm *sm, struct eap_ssl_data *data,
294 const char *label, size_t len)
295 {
296 #ifndef CONFIG_FIPS
297 struct tls_keys keys;
298 #endif /* CONFIG_FIPS */
299 u8 *rnd = NULL, *out;
300
301 out = os_malloc(len);
302 if (out == NULL)
303 return NULL;
304
305 /* First, try to use TLS library function for PRF, if available. */
306 if (tls_connection_prf(data->ssl_ctx, data->conn, label, 0, out, len)
307 == 0)
308 return out;
309
310 #ifndef CONFIG_FIPS
311 /*
312 * TLS library did not support key generation, so get the needed TLS
313 * session parameters and use an internal implementation of TLS PRF to
314 * derive the key.
315 */
316 if (tls_connection_get_keys(data->ssl_ctx, data->conn, &keys))
317 goto fail;
318
319 if (keys.client_random == NULL || keys.server_random == NULL ||
320 keys.master_key == NULL)
321 goto fail;
322
323 rnd = os_malloc(keys.client_random_len + keys.server_random_len);
324 if (rnd == NULL)
325 goto fail;
326 os_memcpy(rnd, keys.client_random, keys.client_random_len);
327 os_memcpy(rnd + keys.client_random_len, keys.server_random,
328 keys.server_random_len);
329
330 if (tls_prf_sha1_md5(keys.master_key, keys.master_key_len,
331 label, rnd, keys.client_random_len +
332 keys.server_random_len, out, len))
333 goto fail;
334
335 os_free(rnd);
336 return out;
337
338 fail:
339 #endif /* CONFIG_FIPS */
340 os_free(out);
341 os_free(rnd);
342 return NULL;
343 }
344
345
346 /**
347 * eap_peer_tls_derive_session_id - Derive a Session-Id based on TLS data
348 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
349 * @data: Data for TLS processing
350 * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
351 * @len: Pointer to length of the session ID generated
352 * Returns: Pointer to allocated Session-Id on success or %NULL on failure
353 *
354 * This function derive the Session-Id based on the TLS session data
355 * (client/server random and method type).
356 *
357 * The caller is responsible for freeing the returned buffer.
358 */
eap_peer_tls_derive_session_id(struct eap_sm * sm,struct eap_ssl_data * data,u8 eap_type,size_t * len)359 u8 * eap_peer_tls_derive_session_id(struct eap_sm *sm,
360 struct eap_ssl_data *data, u8 eap_type,
361 size_t *len)
362 {
363 struct tls_keys keys;
364 u8 *out;
365
366 /*
367 * TLS library did not support session ID generation,
368 * so get the needed TLS session parameters
369 */
370 if (tls_connection_get_keys(sm->ssl_ctx, data->conn, &keys))
371 return NULL;
372
373 if (keys.client_random == NULL || keys.server_random == NULL ||
374 keys.master_key == NULL)
375 return NULL;
376
377 *len = 1 + keys.client_random_len + keys.server_random_len;
378 out = os_malloc(*len);
379 if (out == NULL)
380 return NULL;
381
382 /* Session-Id = EAP type || client.random || server.random */
383 out[0] = eap_type;
384 os_memcpy(out + 1, keys.client_random, keys.client_random_len);
385 os_memcpy(out + 1 + keys.client_random_len, keys.server_random,
386 keys.server_random_len);
387
388 return out;
389 }
390
391
392 /**
393 * eap_peer_tls_reassemble_fragment - Reassemble a received fragment
394 * @data: Data for TLS processing
395 * @in_data: Next incoming TLS segment
396 * Returns: 0 on success, 1 if more data is needed for the full message, or
397 * -1 on error
398 */
eap_peer_tls_reassemble_fragment(struct eap_ssl_data * data,const struct wpabuf * in_data)399 static int eap_peer_tls_reassemble_fragment(struct eap_ssl_data *data,
400 const struct wpabuf *in_data)
401 {
402 size_t tls_in_len, in_len;
403
404 tls_in_len = data->tls_in ? wpabuf_len(data->tls_in) : 0;
405 in_len = in_data ? wpabuf_len(in_data) : 0;
406
407 if (tls_in_len + in_len == 0) {
408 /* No message data received?! */
409 wpa_printf(MSG_WARNING, "SSL: Invalid reassembly state: "
410 "tls_in_left=%lu tls_in_len=%lu in_len=%lu",
411 (unsigned long) data->tls_in_left,
412 (unsigned long) tls_in_len,
413 (unsigned long) in_len);
414 eap_peer_tls_reset_input(data);
415 return -1;
416 }
417
418 if (tls_in_len + in_len > 65536) {
419 /*
420 * Limit length to avoid rogue servers from causing large
421 * memory allocations.
422 */
423 wpa_printf(MSG_INFO, "SSL: Too long TLS fragment (size over "
424 "64 kB)");
425 eap_peer_tls_reset_input(data);
426 return -1;
427 }
428
429 if (in_len > data->tls_in_left) {
430 /* Sender is doing something odd - reject message */
431 wpa_printf(MSG_INFO, "SSL: more data than TLS message length "
432 "indicated");
433 eap_peer_tls_reset_input(data);
434 return -1;
435 }
436
437 if (wpabuf_resize(&data->tls_in, in_len) < 0) {
438 wpa_printf(MSG_INFO, "SSL: Could not allocate memory for TLS "
439 "data");
440 eap_peer_tls_reset_input(data);
441 return -1;
442 }
443 if (in_data)
444 wpabuf_put_buf(data->tls_in, in_data);
445 data->tls_in_left -= in_len;
446
447 if (data->tls_in_left > 0) {
448 wpa_printf(MSG_DEBUG, "SSL: Need %lu bytes more input "
449 "data", (unsigned long) data->tls_in_left);
450 return 1;
451 }
452
453 return 0;
454 }
455
456
457 /**
458 * eap_peer_tls_data_reassemble - Reassemble TLS data
459 * @data: Data for TLS processing
460 * @in_data: Next incoming TLS segment
461 * @need_more_input: Variable for returning whether more input data is needed
462 * to reassemble this TLS packet
463 * Returns: Pointer to output data, %NULL on error or when more data is needed
464 * for the full message (in which case, *need_more_input is also set to 1).
465 *
466 * This function reassembles TLS fragments. Caller must not free the returned
467 * data buffer since an internal pointer to it is maintained.
468 */
eap_peer_tls_data_reassemble(struct eap_ssl_data * data,const struct wpabuf * in_data,int * need_more_input)469 static const struct wpabuf * eap_peer_tls_data_reassemble(
470 struct eap_ssl_data *data, const struct wpabuf *in_data,
471 int *need_more_input)
472 {
473 *need_more_input = 0;
474
475 if (data->tls_in_left > wpabuf_len(in_data) || data->tls_in) {
476 /* Message has fragments */
477 int res = eap_peer_tls_reassemble_fragment(data, in_data);
478 if (res) {
479 if (res == 1)
480 *need_more_input = 1;
481 return NULL;
482 }
483
484 /* Message is now fully reassembled. */
485 } else {
486 /* No fragments in this message, so just make a copy of it. */
487 data->tls_in_left = 0;
488 data->tls_in = wpabuf_dup(in_data);
489 if (data->tls_in == NULL)
490 return NULL;
491 }
492
493 return data->tls_in;
494 }
495
496
497 /**
498 * eap_tls_process_input - Process incoming TLS message
499 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
500 * @data: Data for TLS processing
501 * @in_data: Message received from the server
502 * @in_len: Length of in_data
503 * @out_data: Buffer for returning a pointer to application data (if available)
504 * Returns: 0 on success, 1 if more input data is needed, 2 if application data
505 * is available, -1 on failure
506 */
eap_tls_process_input(struct eap_sm * sm,struct eap_ssl_data * data,const u8 * in_data,size_t in_len,struct wpabuf ** out_data)507 static int eap_tls_process_input(struct eap_sm *sm, struct eap_ssl_data *data,
508 const u8 *in_data, size_t in_len,
509 struct wpabuf **out_data)
510 {
511 const struct wpabuf *msg;
512 int need_more_input;
513 struct wpabuf *appl_data;
514 struct wpabuf buf;
515
516 wpabuf_set(&buf, in_data, in_len);
517 msg = eap_peer_tls_data_reassemble(data, &buf, &need_more_input);
518 if (msg == NULL)
519 return need_more_input ? 1 : -1;
520
521 /* Full TLS message reassembled - continue handshake processing */
522 if (data->tls_out) {
523 /* This should not happen.. */
524 wpa_printf(MSG_INFO, "SSL: eap_tls_process_input - pending "
525 "tls_out data even though tls_out_len = 0");
526 wpabuf_free(data->tls_out);
527 WPA_ASSERT(data->tls_out == NULL);
528 }
529 appl_data = NULL;
530 data->tls_out = tls_connection_handshake(data->ssl_ctx, data->conn,
531 msg, &appl_data);
532
533 eap_peer_tls_reset_input(data);
534
535 if (appl_data &&
536 tls_connection_established(data->ssl_ctx, data->conn) &&
537 !tls_connection_get_failed(data->ssl_ctx, data->conn)) {
538 wpa_hexdump_buf_key(MSG_MSGDUMP, "SSL: Application data",
539 appl_data);
540 *out_data = appl_data;
541 return 2;
542 }
543
544 wpabuf_free(appl_data);
545
546 return 0;
547 }
548
549
550 /**
551 * eap_tls_process_output - Process outgoing TLS message
552 * @data: Data for TLS processing
553 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
554 * @peap_version: Version number for EAP-PEAP/TTLS
555 * @id: EAP identifier for the response
556 * @ret: Return value to use on success
557 * @out_data: Buffer for returning the allocated output buffer
558 * Returns: ret (0 or 1) on success, -1 on failure
559 */
eap_tls_process_output(struct eap_ssl_data * data,EapType eap_type,int peap_version,u8 id,int ret,struct wpabuf ** out_data)560 static int eap_tls_process_output(struct eap_ssl_data *data, EapType eap_type,
561 int peap_version, u8 id, int ret,
562 struct wpabuf **out_data)
563 {
564 size_t len;
565 u8 *flags;
566 int more_fragments, length_included;
567
568 if (data->tls_out == NULL)
569 return -1;
570 len = wpabuf_len(data->tls_out) - data->tls_out_pos;
571 wpa_printf(MSG_DEBUG, "SSL: %lu bytes left to be sent out (of total "
572 "%lu bytes)",
573 (unsigned long) len,
574 (unsigned long) wpabuf_len(data->tls_out));
575
576 /*
577 * Limit outgoing message to the configured maximum size. Fragment
578 * message if needed.
579 */
580 if (len > data->tls_out_limit) {
581 more_fragments = 1;
582 len = data->tls_out_limit;
583 wpa_printf(MSG_DEBUG, "SSL: sending %lu bytes, more fragments "
584 "will follow", (unsigned long) len);
585 } else
586 more_fragments = 0;
587
588 length_included = data->tls_out_pos == 0 &&
589 (wpabuf_len(data->tls_out) > data->tls_out_limit ||
590 data->include_tls_length);
591 if (!length_included &&
592 eap_type == EAP_TYPE_PEAP && peap_version == 0 &&
593 !tls_connection_established(data->eap->ssl_ctx, data->conn)) {
594 /*
595 * Windows Server 2008 NPS really wants to have the TLS Message
596 * length included in phase 0 even for unfragmented frames or
597 * it will get very confused with Compound MAC calculation and
598 * Outer TLVs.
599 */
600 length_included = 1;
601 }
602
603 *out_data = eap_tls_msg_alloc(eap_type, 1 + length_included * 4 + len,
604 EAP_CODE_RESPONSE, id);
605 if (*out_data == NULL)
606 return -1;
607
608 flags = wpabuf_put(*out_data, 1);
609 *flags = peap_version;
610 if (more_fragments)
611 *flags |= EAP_TLS_FLAGS_MORE_FRAGMENTS;
612 if (length_included) {
613 *flags |= EAP_TLS_FLAGS_LENGTH_INCLUDED;
614 wpabuf_put_be32(*out_data, wpabuf_len(data->tls_out));
615 }
616
617 wpabuf_put_data(*out_data,
618 wpabuf_head_u8(data->tls_out) + data->tls_out_pos,
619 len);
620 data->tls_out_pos += len;
621
622 if (!more_fragments)
623 eap_peer_tls_reset_output(data);
624
625 return ret;
626 }
627
628
629 /**
630 * eap_peer_tls_process_helper - Process TLS handshake message
631 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
632 * @data: Data for TLS processing
633 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
634 * @peap_version: Version number for EAP-PEAP/TTLS
635 * @id: EAP identifier for the response
636 * @in_data: Message received from the server
637 * @in_len: Length of in_data
638 * @out_data: Buffer for returning a pointer to the response message
639 * Returns: 0 on success, 1 if more input data is needed, 2 if application data
640 * is available, or -1 on failure
641 *
642 * This function can be used to process TLS handshake messages. It reassembles
643 * the received fragments and uses a TLS library to process the messages. The
644 * response data from the TLS library is fragmented to suitable output messages
645 * that the caller can send out.
646 *
647 * out_data is used to return the response message if the return value of this
648 * function is 0, 2, or -1. In case of failure, the message is likely a TLS
649 * alarm message. The caller is responsible for freeing the allocated buffer if
650 * *out_data is not %NULL.
651 *
652 * This function is called for each received TLS message during the TLS
653 * handshake after eap_peer_tls_process_init() call and possible processing of
654 * TLS Flags field. Once the handshake has been completed, i.e., when
655 * tls_connection_established() returns 1, EAP method specific decrypting of
656 * the tunneled data is used.
657 */
eap_peer_tls_process_helper(struct eap_sm * sm,struct eap_ssl_data * data,EapType eap_type,int peap_version,u8 id,const u8 * in_data,size_t in_len,struct wpabuf ** out_data)658 int eap_peer_tls_process_helper(struct eap_sm *sm, struct eap_ssl_data *data,
659 EapType eap_type, int peap_version,
660 u8 id, const u8 *in_data, size_t in_len,
661 struct wpabuf **out_data)
662 {
663 int ret = 0;
664
665 *out_data = NULL;
666
667 if (data->tls_out && wpabuf_len(data->tls_out) > 0 && in_len > 0) {
668 wpa_printf(MSG_DEBUG, "SSL: Received non-ACK when output "
669 "fragments are waiting to be sent out");
670 return -1;
671 }
672
673 if (data->tls_out == NULL || wpabuf_len(data->tls_out) == 0) {
674 /*
675 * No more data to send out - expect to receive more data from
676 * the AS.
677 */
678 int res = eap_tls_process_input(sm, data, in_data, in_len,
679 out_data);
680 if (res) {
681 /*
682 * Input processing failed (res = -1) or more data is
683 * needed (res = 1).
684 */
685 return res;
686 }
687
688 /*
689 * The incoming message has been reassembled and processed. The
690 * response was allocated into data->tls_out buffer.
691 */
692 }
693
694 if (data->tls_out == NULL) {
695 /*
696 * No outgoing fragments remaining from the previous message
697 * and no new message generated. This indicates an error in TLS
698 * processing.
699 */
700 eap_peer_tls_reset_output(data);
701 return -1;
702 }
703
704 if (tls_connection_get_failed(data->ssl_ctx, data->conn)) {
705 /* TLS processing has failed - return error */
706 wpa_printf(MSG_DEBUG, "SSL: Failed - tls_out available to "
707 "report error");
708 ret = -1;
709 /* TODO: clean pin if engine used? */
710 }
711
712 if (data->tls_out == NULL || wpabuf_len(data->tls_out) == 0) {
713 /*
714 * TLS negotiation should now be complete since all other cases
715 * needing more data should have been caught above based on
716 * the TLS Message Length field.
717 */
718 wpa_printf(MSG_DEBUG, "SSL: No data to be sent out");
719 wpabuf_free(data->tls_out);
720 data->tls_out = NULL;
721 return 1;
722 }
723
724 /* Send the pending message (in fragments, if needed). */
725 return eap_tls_process_output(data, eap_type, peap_version, id, ret,
726 out_data);
727 }
728
729
730 /**
731 * eap_peer_tls_build_ack - Build a TLS ACK frame
732 * @id: EAP identifier for the response
733 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
734 * @peap_version: Version number for EAP-PEAP/TTLS
735 * Returns: Pointer to the allocated ACK frame or %NULL on failure
736 */
eap_peer_tls_build_ack(u8 id,EapType eap_type,int peap_version)737 struct wpabuf * eap_peer_tls_build_ack(u8 id, EapType eap_type,
738 int peap_version)
739 {
740 struct wpabuf *resp;
741
742 resp = eap_tls_msg_alloc(eap_type, 1, EAP_CODE_RESPONSE, id);
743 if (resp == NULL)
744 return NULL;
745 wpa_printf(MSG_DEBUG, "SSL: Building ACK (type=%d id=%d ver=%d)",
746 (int) eap_type, id, peap_version);
747 wpabuf_put_u8(resp, peap_version); /* Flags */
748 return resp;
749 }
750
751
752 /**
753 * eap_peer_tls_reauth_init - Re-initialize shared TLS for session resumption
754 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
755 * @data: Data for TLS processing
756 * Returns: 0 on success, -1 on failure
757 */
eap_peer_tls_reauth_init(struct eap_sm * sm,struct eap_ssl_data * data)758 int eap_peer_tls_reauth_init(struct eap_sm *sm, struct eap_ssl_data *data)
759 {
760 eap_peer_tls_reset_input(data);
761 eap_peer_tls_reset_output(data);
762 return tls_connection_shutdown(data->ssl_ctx, data->conn);
763 }
764
765
766 /**
767 * eap_peer_tls_status - Get TLS status
768 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
769 * @data: Data for TLS processing
770 * @buf: Buffer for status information
771 * @buflen: Maximum buffer length
772 * @verbose: Whether to include verbose status information
773 * Returns: Number of bytes written to buf.
774 */
eap_peer_tls_status(struct eap_sm * sm,struct eap_ssl_data * data,char * buf,size_t buflen,int verbose)775 int eap_peer_tls_status(struct eap_sm *sm, struct eap_ssl_data *data,
776 char *buf, size_t buflen, int verbose)
777 {
778 char name[128];
779 int len = 0, ret;
780
781 if (tls_get_cipher(data->ssl_ctx, data->conn, name, sizeof(name)) == 0)
782 {
783 ret = os_snprintf(buf + len, buflen - len,
784 "EAP TLS cipher=%s\n", name);
785 if (ret < 0 || (size_t) ret >= buflen - len)
786 return len;
787 len += ret;
788 }
789
790 return len;
791 }
792
793
794 /**
795 * eap_peer_tls_process_init - Initial validation/processing of EAP requests
796 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
797 * @data: Data for TLS processing
798 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
799 * @ret: Return values from EAP request validation and processing
800 * @reqData: EAP request to be processed (eapReqData)
801 * @len: Buffer for returning length of the remaining payload
802 * @flags: Buffer for returning TLS flags
803 * Returns: Pointer to payload after TLS flags and length or %NULL on failure
804 *
805 * This function validates the EAP header and processes the optional TLS
806 * Message Length field. If this is the first fragment of a TLS message, the
807 * TLS reassembly code is initialized to receive the indicated number of bytes.
808 *
809 * EAP-TLS, EAP-PEAP, EAP-TTLS, and EAP-FAST methods are expected to use this
810 * function as the first step in processing received messages. They will need
811 * to process the flags (apart from Message Length Included) that are returned
812 * through the flags pointer and the message payload that will be returned (and
813 * the length is returned through the len pointer). Return values (ret) are set
814 * for continuation of EAP method processing. The caller is responsible for
815 * setting these to indicate completion (either success or failure) based on
816 * the authentication result.
817 */
eap_peer_tls_process_init(struct eap_sm * sm,struct eap_ssl_data * data,EapType eap_type,struct eap_method_ret * ret,const struct wpabuf * reqData,size_t * len,u8 * flags)818 const u8 * eap_peer_tls_process_init(struct eap_sm *sm,
819 struct eap_ssl_data *data,
820 EapType eap_type,
821 struct eap_method_ret *ret,
822 const struct wpabuf *reqData,
823 size_t *len, u8 *flags)
824 {
825 const u8 *pos;
826 size_t left;
827 unsigned int tls_msg_len;
828
829 if (tls_get_errors(data->ssl_ctx)) {
830 wpa_printf(MSG_INFO, "SSL: TLS errors detected");
831 ret->ignore = TRUE;
832 return NULL;
833 }
834
835 if (eap_type == EAP_UNAUTH_TLS_TYPE)
836 pos = eap_hdr_validate(EAP_VENDOR_UNAUTH_TLS,
837 EAP_VENDOR_TYPE_UNAUTH_TLS, reqData,
838 &left);
839 else
840 pos = eap_hdr_validate(EAP_VENDOR_IETF, eap_type, reqData,
841 &left);
842 if (pos == NULL) {
843 ret->ignore = TRUE;
844 return NULL;
845 }
846 if (left == 0) {
847 wpa_printf(MSG_DEBUG, "SSL: Invalid TLS message: no Flags "
848 "octet included");
849 if (!sm->workaround) {
850 ret->ignore = TRUE;
851 return NULL;
852 }
853
854 wpa_printf(MSG_DEBUG, "SSL: Workaround - assume no Flags "
855 "indicates ACK frame");
856 *flags = 0;
857 } else {
858 *flags = *pos++;
859 left--;
860 }
861 wpa_printf(MSG_DEBUG, "SSL: Received packet(len=%lu) - "
862 "Flags 0x%02x", (unsigned long) wpabuf_len(reqData),
863 *flags);
864 if (*flags & EAP_TLS_FLAGS_LENGTH_INCLUDED) {
865 if (left < 4) {
866 wpa_printf(MSG_INFO, "SSL: Short frame with TLS "
867 "length");
868 ret->ignore = TRUE;
869 return NULL;
870 }
871 tls_msg_len = WPA_GET_BE32(pos);
872 wpa_printf(MSG_DEBUG, "SSL: TLS Message Length: %d",
873 tls_msg_len);
874 if (data->tls_in_left == 0) {
875 data->tls_in_total = tls_msg_len;
876 data->tls_in_left = tls_msg_len;
877 wpabuf_free(data->tls_in);
878 data->tls_in = NULL;
879 }
880 pos += 4;
881 left -= 4;
882
883 if (left > tls_msg_len) {
884 wpa_printf(MSG_INFO, "SSL: TLS Message Length (%d "
885 "bytes) smaller than this fragment (%d "
886 "bytes)", (int) tls_msg_len, (int) left);
887 ret->ignore = TRUE;
888 return NULL;
889 }
890 }
891
892 ret->ignore = FALSE;
893 ret->methodState = METHOD_MAY_CONT;
894 ret->decision = DECISION_FAIL;
895 ret->allowNotifications = TRUE;
896
897 *len = left;
898 return pos;
899 }
900
901
902 /**
903 * eap_peer_tls_reset_input - Reset input buffers
904 * @data: Data for TLS processing
905 *
906 * This function frees any allocated memory for input buffers and resets input
907 * state.
908 */
eap_peer_tls_reset_input(struct eap_ssl_data * data)909 void eap_peer_tls_reset_input(struct eap_ssl_data *data)
910 {
911 data->tls_in_left = data->tls_in_total = 0;
912 wpabuf_free(data->tls_in);
913 data->tls_in = NULL;
914 }
915
916
917 /**
918 * eap_peer_tls_reset_output - Reset output buffers
919 * @data: Data for TLS processing
920 *
921 * This function frees any allocated memory for output buffers and resets
922 * output state.
923 */
eap_peer_tls_reset_output(struct eap_ssl_data * data)924 void eap_peer_tls_reset_output(struct eap_ssl_data *data)
925 {
926 data->tls_out_pos = 0;
927 wpabuf_free(data->tls_out);
928 data->tls_out = NULL;
929 }
930
931
932 /**
933 * eap_peer_tls_decrypt - Decrypt received phase 2 TLS message
934 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
935 * @data: Data for TLS processing
936 * @in_data: Message received from the server
937 * @in_decrypted: Buffer for returning a pointer to the decrypted message
938 * Returns: 0 on success, 1 if more input data is needed, or -1 on failure
939 */
eap_peer_tls_decrypt(struct eap_sm * sm,struct eap_ssl_data * data,const struct wpabuf * in_data,struct wpabuf ** in_decrypted)940 int eap_peer_tls_decrypt(struct eap_sm *sm, struct eap_ssl_data *data,
941 const struct wpabuf *in_data,
942 struct wpabuf **in_decrypted)
943 {
944 const struct wpabuf *msg;
945 int need_more_input;
946
947 msg = eap_peer_tls_data_reassemble(data, in_data, &need_more_input);
948 if (msg == NULL)
949 return need_more_input ? 1 : -1;
950
951 *in_decrypted = tls_connection_decrypt(data->ssl_ctx, data->conn, msg);
952 eap_peer_tls_reset_input(data);
953 if (*in_decrypted == NULL) {
954 wpa_printf(MSG_INFO, "SSL: Failed to decrypt Phase 2 data");
955 return -1;
956 }
957 return 0;
958 }
959
960
961 /**
962 * eap_peer_tls_encrypt - Encrypt phase 2 TLS message
963 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
964 * @data: Data for TLS processing
965 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
966 * @peap_version: Version number for EAP-PEAP/TTLS
967 * @id: EAP identifier for the response
968 * @in_data: Plaintext phase 2 data to encrypt or %NULL to continue fragments
969 * @out_data: Buffer for returning a pointer to the encrypted response message
970 * Returns: 0 on success, -1 on failure
971 */
eap_peer_tls_encrypt(struct eap_sm * sm,struct eap_ssl_data * data,EapType eap_type,int peap_version,u8 id,const struct wpabuf * in_data,struct wpabuf ** out_data)972 int eap_peer_tls_encrypt(struct eap_sm *sm, struct eap_ssl_data *data,
973 EapType eap_type, int peap_version, u8 id,
974 const struct wpabuf *in_data,
975 struct wpabuf **out_data)
976 {
977 if (in_data) {
978 eap_peer_tls_reset_output(data);
979 data->tls_out = tls_connection_encrypt(data->ssl_ctx,
980 data->conn, in_data);
981 if (data->tls_out == NULL) {
982 wpa_printf(MSG_INFO, "SSL: Failed to encrypt Phase 2 "
983 "data (in_len=%lu)",
984 (unsigned long) wpabuf_len(in_data));
985 eap_peer_tls_reset_output(data);
986 return -1;
987 }
988 }
989
990 return eap_tls_process_output(data, eap_type, peap_version, id, 0,
991 out_data);
992 }
993
994
995 /**
996 * eap_peer_select_phase2_methods - Select phase 2 EAP method
997 * @config: Pointer to the network configuration
998 * @prefix: 'phase2' configuration prefix, e.g., "auth="
999 * @types: Buffer for returning allocated list of allowed EAP methods
1000 * @num_types: Buffer for returning number of allocated EAP methods
1001 * Returns: 0 on success, -1 on failure
1002 *
1003 * This function is used to parse EAP method list and select allowed methods
1004 * for Phase2 authentication.
1005 */
eap_peer_select_phase2_methods(struct eap_peer_config * config,const char * prefix,struct eap_method_type ** types,size_t * num_types)1006 int eap_peer_select_phase2_methods(struct eap_peer_config *config,
1007 const char *prefix,
1008 struct eap_method_type **types,
1009 size_t *num_types)
1010 {
1011 char *start, *pos, *buf;
1012 struct eap_method_type *methods = NULL, *_methods;
1013 u8 method;
1014 size_t num_methods = 0, prefix_len;
1015
1016 if (config == NULL || config->phase2 == NULL)
1017 goto get_defaults;
1018
1019 start = buf = os_strdup(config->phase2);
1020 if (buf == NULL)
1021 return -1;
1022
1023 prefix_len = os_strlen(prefix);
1024
1025 while (start && *start != '\0') {
1026 int vendor;
1027 pos = os_strstr(start, prefix);
1028 if (pos == NULL)
1029 break;
1030 if (start != pos && *(pos - 1) != ' ') {
1031 start = pos + prefix_len;
1032 continue;
1033 }
1034
1035 start = pos + prefix_len;
1036 pos = os_strchr(start, ' ');
1037 if (pos)
1038 *pos++ = '\0';
1039 method = eap_get_phase2_type(start, &vendor);
1040 if (vendor == EAP_VENDOR_IETF && method == EAP_TYPE_NONE) {
1041 wpa_printf(MSG_ERROR, "TLS: Unsupported Phase2 EAP "
1042 "method '%s'", start);
1043 } else {
1044 num_methods++;
1045 _methods = os_realloc_array(methods, num_methods,
1046 sizeof(*methods));
1047 if (_methods == NULL) {
1048 os_free(methods);
1049 os_free(buf);
1050 return -1;
1051 }
1052 methods = _methods;
1053 methods[num_methods - 1].vendor = vendor;
1054 methods[num_methods - 1].method = method;
1055 }
1056
1057 start = pos;
1058 }
1059
1060 os_free(buf);
1061
1062 get_defaults:
1063 if (methods == NULL)
1064 methods = eap_get_phase2_types(config, &num_methods);
1065
1066 if (methods == NULL) {
1067 wpa_printf(MSG_ERROR, "TLS: No Phase2 EAP methods available");
1068 return -1;
1069 }
1070 wpa_hexdump(MSG_DEBUG, "TLS: Phase2 EAP types",
1071 (u8 *) methods,
1072 num_methods * sizeof(struct eap_method_type));
1073
1074 *types = methods;
1075 *num_types = num_methods;
1076
1077 return 0;
1078 }
1079
1080
1081 /**
1082 * eap_peer_tls_phase2_nak - Generate EAP-Nak for Phase 2
1083 * @types: Buffer for returning allocated list of allowed EAP methods
1084 * @num_types: Buffer for returning number of allocated EAP methods
1085 * @hdr: EAP-Request header (and the following EAP type octet)
1086 * @resp: Buffer for returning the EAP-Nak message
1087 * Returns: 0 on success, -1 on failure
1088 */
eap_peer_tls_phase2_nak(struct eap_method_type * types,size_t num_types,struct eap_hdr * hdr,struct wpabuf ** resp)1089 int eap_peer_tls_phase2_nak(struct eap_method_type *types, size_t num_types,
1090 struct eap_hdr *hdr, struct wpabuf **resp)
1091 {
1092 u8 *pos = (u8 *) (hdr + 1);
1093 size_t i;
1094
1095 /* TODO: add support for expanded Nak */
1096 wpa_printf(MSG_DEBUG, "TLS: Phase 2 Request: Nak type=%d", *pos);
1097 wpa_hexdump(MSG_DEBUG, "TLS: Allowed Phase2 EAP types",
1098 (u8 *) types, num_types * sizeof(struct eap_method_type));
1099 *resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_NAK, num_types,
1100 EAP_CODE_RESPONSE, hdr->identifier);
1101 if (*resp == NULL)
1102 return -1;
1103
1104 for (i = 0; i < num_types; i++) {
1105 if (types[i].vendor == EAP_VENDOR_IETF &&
1106 types[i].method < 256)
1107 wpabuf_put_u8(*resp, types[i].method);
1108 }
1109
1110 eap_update_len(*resp);
1111
1112 return 0;
1113 }
1114