1 /*
2 * EAP peer: EAP-TLS/PEAP/TTLS/FAST common functions
3 * Copyright (c) 2004-2012, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "crypto/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 data->conn = tls_connection_init(data->ssl_ctx);
168 if (data->conn == NULL) {
169 wpa_printf(MSG_INFO, "SSL: Failed to initialize new TLS "
170 "connection");
171 return -1;
172 }
173
174 res = tls_connection_set_params(data->ssl_ctx, data->conn, params);
175 if (res == TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED) {
176 /*
177 * At this point with the pkcs11 engine the PIN might be wrong.
178 * We reset the PIN in the configuration to be sure to not use
179 * it again and the calling function must request a new one.
180 */
181 os_free(config->pin);
182 config->pin = NULL;
183 } else if (res == TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED) {
184 wpa_printf(MSG_INFO, "TLS: Failed to load private key");
185 /*
186 * We do not know exactly but maybe the PIN was wrong,
187 * so ask for a new one.
188 */
189 os_free(config->pin);
190 config->pin = NULL;
191 eap_sm_request_pin(sm);
192 sm->ignore = TRUE;
193 tls_connection_deinit(data->ssl_ctx, data->conn);
194 data->conn = NULL;
195 return -1;
196 } else if (res) {
197 wpa_printf(MSG_INFO, "TLS: Failed to set TLS connection "
198 "parameters");
199 tls_connection_deinit(data->ssl_ctx, data->conn);
200 data->conn = NULL;
201 return -1;
202 }
203
204 return 0;
205 }
206
207
208 /**
209 * eap_peer_tls_ssl_init - Initialize shared TLS functionality
210 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
211 * @data: Data for TLS processing
212 * @config: Pointer to the network configuration
213 * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
214 * Returns: 0 on success, -1 on failure
215 *
216 * This function is used to initialize shared TLS functionality for EAP-TLS,
217 * EAP-PEAP, EAP-TTLS, and EAP-FAST.
218 */
eap_peer_tls_ssl_init(struct eap_sm * sm,struct eap_ssl_data * data,struct eap_peer_config * config,u8 eap_type)219 int eap_peer_tls_ssl_init(struct eap_sm *sm, struct eap_ssl_data *data,
220 struct eap_peer_config *config, u8 eap_type)
221 {
222 struct tls_connection_params params;
223
224 if (config == NULL)
225 return -1;
226
227 data->eap = sm;
228 data->eap_type = eap_type;
229 data->phase2 = sm->init_phase2;
230 data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
231 sm->ssl_ctx;
232 if (eap_tls_params_from_conf(sm, data, ¶ms, config, data->phase2) <
233 0)
234 return -1;
235
236 if (eap_tls_init_connection(sm, data, config, ¶ms) < 0)
237 return -1;
238
239 data->tls_out_limit = config->fragment_size;
240 if (data->phase2) {
241 /* Limit the fragment size in the inner TLS authentication
242 * since the outer authentication with EAP-PEAP does not yet
243 * support fragmentation */
244 if (data->tls_out_limit > 100)
245 data->tls_out_limit -= 100;
246 }
247
248 if (config->phase1 &&
249 os_strstr(config->phase1, "include_tls_length=1")) {
250 wpa_printf(MSG_DEBUG, "TLS: Include TLS Message Length in "
251 "unfragmented packets");
252 data->include_tls_length = 1;
253 }
254
255 return 0;
256 }
257
258
259 /**
260 * eap_peer_tls_ssl_deinit - Deinitialize shared TLS functionality
261 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
262 * @data: Data for TLS processing
263 *
264 * This function deinitializes shared TLS functionality that was initialized
265 * with eap_peer_tls_ssl_init().
266 */
eap_peer_tls_ssl_deinit(struct eap_sm * sm,struct eap_ssl_data * data)267 void eap_peer_tls_ssl_deinit(struct eap_sm *sm, struct eap_ssl_data *data)
268 {
269 tls_connection_deinit(data->ssl_ctx, data->conn);
270 eap_peer_tls_reset_input(data);
271 eap_peer_tls_reset_output(data);
272 }
273
274
275 /**
276 * eap_peer_tls_derive_key - Derive a key based on TLS session data
277 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
278 * @data: Data for TLS processing
279 * @label: Label string for deriving the keys, e.g., "client EAP encryption"
280 * @len: Length of the key material to generate (usually 64 for MSK)
281 * Returns: Pointer to allocated key on success or %NULL on failure
282 *
283 * This function uses TLS-PRF to generate pseudo-random data based on the TLS
284 * session data (client/server random and master key). Each key type may use a
285 * different label to bind the key usage into the generated material.
286 *
287 * The caller is responsible for freeing the returned buffer.
288 */
eap_peer_tls_derive_key(struct eap_sm * sm,struct eap_ssl_data * data,const char * label,size_t len)289 u8 * eap_peer_tls_derive_key(struct eap_sm *sm, struct eap_ssl_data *data,
290 const char *label, size_t len)
291 {
292 #ifndef CONFIG_FIPS
293 struct tls_keys keys;
294 #endif /* CONFIG_FIPS */
295 u8 *rnd = NULL, *out;
296
297 out = os_malloc(len);
298 if (out == NULL)
299 return NULL;
300
301 /* First, try to use TLS library function for PRF, if available. */
302 if (tls_connection_prf(data->ssl_ctx, data->conn, label, 0, out, len)
303 == 0)
304 return out;
305
306 #ifndef CONFIG_FIPS
307 /*
308 * TLS library did not support key generation, so get the needed TLS
309 * session parameters and use an internal implementation of TLS PRF to
310 * derive the key.
311 */
312 if (tls_connection_get_keys(data->ssl_ctx, data->conn, &keys))
313 goto fail;
314
315 if (keys.client_random == NULL || keys.server_random == NULL ||
316 keys.master_key == NULL)
317 goto fail;
318
319 rnd = os_malloc(keys.client_random_len + keys.server_random_len);
320 if (rnd == NULL)
321 goto fail;
322 os_memcpy(rnd, keys.client_random, keys.client_random_len);
323 os_memcpy(rnd + keys.client_random_len, keys.server_random,
324 keys.server_random_len);
325
326 if (tls_prf_sha1_md5(keys.master_key, keys.master_key_len,
327 label, rnd, keys.client_random_len +
328 keys.server_random_len, out, len))
329 goto fail;
330
331 os_free(rnd);
332 return out;
333
334 fail:
335 #endif /* CONFIG_FIPS */
336 os_free(out);
337 os_free(rnd);
338 return NULL;
339 }
340
341
342 /**
343 * eap_peer_tls_derive_session_id - Derive a Session-Id based on TLS data
344 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
345 * @data: Data for TLS processing
346 * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
347 * @len: Pointer to length of the session ID generated
348 * Returns: Pointer to allocated Session-Id on success or %NULL on failure
349 *
350 * This function derive the Session-Id based on the TLS session data
351 * (client/server random and method type).
352 *
353 * The caller is responsible for freeing the returned buffer.
354 */
eap_peer_tls_derive_session_id(struct eap_sm * sm,struct eap_ssl_data * data,u8 eap_type,size_t * len)355 u8 * eap_peer_tls_derive_session_id(struct eap_sm *sm,
356 struct eap_ssl_data *data, u8 eap_type,
357 size_t *len)
358 {
359 struct tls_keys keys;
360 u8 *out;
361
362 /*
363 * TLS library did not support session ID generation,
364 * so get the needed TLS session parameters
365 */
366 if (tls_connection_get_keys(sm->ssl_ctx, data->conn, &keys))
367 return NULL;
368
369 if (keys.client_random == NULL || keys.server_random == NULL ||
370 keys.master_key == NULL)
371 return NULL;
372
373 *len = 1 + keys.client_random_len + keys.server_random_len;
374 out = os_malloc(*len);
375 if (out == NULL)
376 return NULL;
377
378 /* Session-Id = EAP type || client.random || server.random */
379 out[0] = eap_type;
380 os_memcpy(out + 1, keys.client_random, keys.client_random_len);
381 os_memcpy(out + 1 + keys.client_random_len, keys.server_random,
382 keys.server_random_len);
383
384 return out;
385 }
386
387
388 /**
389 * eap_peer_tls_reassemble_fragment - Reassemble a received fragment
390 * @data: Data for TLS processing
391 * @in_data: Next incoming TLS segment
392 * Returns: 0 on success, 1 if more data is needed for the full message, or
393 * -1 on error
394 */
eap_peer_tls_reassemble_fragment(struct eap_ssl_data * data,const struct wpabuf * in_data)395 static int eap_peer_tls_reassemble_fragment(struct eap_ssl_data *data,
396 const struct wpabuf *in_data)
397 {
398 size_t tls_in_len, in_len;
399
400 tls_in_len = data->tls_in ? wpabuf_len(data->tls_in) : 0;
401 in_len = in_data ? wpabuf_len(in_data) : 0;
402
403 if (tls_in_len + in_len == 0) {
404 /* No message data received?! */
405 wpa_printf(MSG_WARNING, "SSL: Invalid reassembly state: "
406 "tls_in_left=%lu tls_in_len=%lu in_len=%lu",
407 (unsigned long) data->tls_in_left,
408 (unsigned long) tls_in_len,
409 (unsigned long) in_len);
410 eap_peer_tls_reset_input(data);
411 return -1;
412 }
413
414 if (tls_in_len + in_len > 65536) {
415 /*
416 * Limit length to avoid rogue servers from causing large
417 * memory allocations.
418 */
419 wpa_printf(MSG_INFO, "SSL: Too long TLS fragment (size over "
420 "64 kB)");
421 eap_peer_tls_reset_input(data);
422 return -1;
423 }
424
425 if (in_len > data->tls_in_left) {
426 /* Sender is doing something odd - reject message */
427 wpa_printf(MSG_INFO, "SSL: more data than TLS message length "
428 "indicated");
429 eap_peer_tls_reset_input(data);
430 return -1;
431 }
432
433 if (wpabuf_resize(&data->tls_in, in_len) < 0) {
434 wpa_printf(MSG_INFO, "SSL: Could not allocate memory for TLS "
435 "data");
436 eap_peer_tls_reset_input(data);
437 return -1;
438 }
439 if (in_data)
440 wpabuf_put_buf(data->tls_in, in_data);
441 data->tls_in_left -= in_len;
442
443 if (data->tls_in_left > 0) {
444 wpa_printf(MSG_DEBUG, "SSL: Need %lu bytes more input "
445 "data", (unsigned long) data->tls_in_left);
446 return 1;
447 }
448
449 return 0;
450 }
451
452
453 /**
454 * eap_peer_tls_data_reassemble - Reassemble TLS data
455 * @data: Data for TLS processing
456 * @in_data: Next incoming TLS segment
457 * @need_more_input: Variable for returning whether more input data is needed
458 * to reassemble this TLS packet
459 * Returns: Pointer to output data, %NULL on error or when more data is needed
460 * for the full message (in which case, *need_more_input is also set to 1).
461 *
462 * This function reassembles TLS fragments. Caller must not free the returned
463 * data buffer since an internal pointer to it is maintained.
464 */
eap_peer_tls_data_reassemble(struct eap_ssl_data * data,const struct wpabuf * in_data,int * need_more_input)465 static const struct wpabuf * eap_peer_tls_data_reassemble(
466 struct eap_ssl_data *data, const struct wpabuf *in_data,
467 int *need_more_input)
468 {
469 *need_more_input = 0;
470
471 if (data->tls_in_left > wpabuf_len(in_data) || data->tls_in) {
472 /* Message has fragments */
473 int res = eap_peer_tls_reassemble_fragment(data, in_data);
474 if (res) {
475 if (res == 1)
476 *need_more_input = 1;
477 return NULL;
478 }
479
480 /* Message is now fully reassembled. */
481 } else {
482 /* No fragments in this message, so just make a copy of it. */
483 data->tls_in_left = 0;
484 data->tls_in = wpabuf_dup(in_data);
485 if (data->tls_in == NULL)
486 return NULL;
487 }
488
489 return data->tls_in;
490 }
491
492
493 /**
494 * eap_tls_process_input - Process incoming TLS message
495 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
496 * @data: Data for TLS processing
497 * @in_data: Message received from the server
498 * @in_len: Length of in_data
499 * @out_data: Buffer for returning a pointer to application data (if available)
500 * Returns: 0 on success, 1 if more input data is needed, 2 if application data
501 * is available, -1 on failure
502 */
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)503 static int eap_tls_process_input(struct eap_sm *sm, struct eap_ssl_data *data,
504 const u8 *in_data, size_t in_len,
505 struct wpabuf **out_data)
506 {
507 const struct wpabuf *msg;
508 int need_more_input;
509 struct wpabuf *appl_data;
510 struct wpabuf buf;
511
512 wpabuf_set(&buf, in_data, in_len);
513 msg = eap_peer_tls_data_reassemble(data, &buf, &need_more_input);
514 if (msg == NULL)
515 return need_more_input ? 1 : -1;
516
517 /* Full TLS message reassembled - continue handshake processing */
518 if (data->tls_out) {
519 /* This should not happen.. */
520 wpa_printf(MSG_INFO, "SSL: eap_tls_process_input - pending "
521 "tls_out data even though tls_out_len = 0");
522 wpabuf_free(data->tls_out);
523 WPA_ASSERT(data->tls_out == NULL);
524 }
525 appl_data = NULL;
526 data->tls_out = tls_connection_handshake(data->ssl_ctx, data->conn,
527 msg, &appl_data);
528
529 eap_peer_tls_reset_input(data);
530
531 if (appl_data &&
532 tls_connection_established(data->ssl_ctx, data->conn) &&
533 !tls_connection_get_failed(data->ssl_ctx, data->conn)) {
534 wpa_hexdump_buf_key(MSG_MSGDUMP, "SSL: Application data",
535 appl_data);
536 *out_data = appl_data;
537 return 2;
538 }
539
540 wpabuf_free(appl_data);
541
542 return 0;
543 }
544
545
546 /**
547 * eap_tls_process_output - Process outgoing TLS message
548 * @data: Data for TLS processing
549 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
550 * @peap_version: Version number for EAP-PEAP/TTLS
551 * @id: EAP identifier for the response
552 * @ret: Return value to use on success
553 * @out_data: Buffer for returning the allocated output buffer
554 * Returns: ret (0 or 1) on success, -1 on failure
555 */
eap_tls_process_output(struct eap_ssl_data * data,EapType eap_type,int peap_version,u8 id,int ret,struct wpabuf ** out_data)556 static int eap_tls_process_output(struct eap_ssl_data *data, EapType eap_type,
557 int peap_version, u8 id, int ret,
558 struct wpabuf **out_data)
559 {
560 size_t len;
561 u8 *flags;
562 int more_fragments, length_included;
563
564 if (data->tls_out == NULL)
565 return -1;
566 len = wpabuf_len(data->tls_out) - data->tls_out_pos;
567 wpa_printf(MSG_DEBUG, "SSL: %lu bytes left to be sent out (of total "
568 "%lu bytes)",
569 (unsigned long) len,
570 (unsigned long) wpabuf_len(data->tls_out));
571
572 /*
573 * Limit outgoing message to the configured maximum size. Fragment
574 * message if needed.
575 */
576 if (len > data->tls_out_limit) {
577 more_fragments = 1;
578 len = data->tls_out_limit;
579 wpa_printf(MSG_DEBUG, "SSL: sending %lu bytes, more fragments "
580 "will follow", (unsigned long) len);
581 } else
582 more_fragments = 0;
583
584 length_included = data->tls_out_pos == 0 &&
585 (wpabuf_len(data->tls_out) > data->tls_out_limit ||
586 data->include_tls_length);
587 if (!length_included &&
588 eap_type == EAP_TYPE_PEAP && peap_version == 0 &&
589 !tls_connection_established(data->eap->ssl_ctx, data->conn)) {
590 /*
591 * Windows Server 2008 NPS really wants to have the TLS Message
592 * length included in phase 0 even for unfragmented frames or
593 * it will get very confused with Compound MAC calculation and
594 * Outer TLVs.
595 */
596 length_included = 1;
597 }
598
599 *out_data = eap_tls_msg_alloc(eap_type, 1 + length_included * 4 + len,
600 EAP_CODE_RESPONSE, id);
601 if (*out_data == NULL)
602 return -1;
603
604 flags = wpabuf_put(*out_data, 1);
605 *flags = peap_version;
606 if (more_fragments)
607 *flags |= EAP_TLS_FLAGS_MORE_FRAGMENTS;
608 if (length_included) {
609 *flags |= EAP_TLS_FLAGS_LENGTH_INCLUDED;
610 wpabuf_put_be32(*out_data, wpabuf_len(data->tls_out));
611 }
612
613 wpabuf_put_data(*out_data,
614 wpabuf_head_u8(data->tls_out) + data->tls_out_pos,
615 len);
616 data->tls_out_pos += len;
617
618 if (!more_fragments)
619 eap_peer_tls_reset_output(data);
620
621 return ret;
622 }
623
624
625 /**
626 * eap_peer_tls_process_helper - Process TLS handshake message
627 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
628 * @data: Data for TLS processing
629 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
630 * @peap_version: Version number for EAP-PEAP/TTLS
631 * @id: EAP identifier for the response
632 * @in_data: Message received from the server
633 * @in_len: Length of in_data
634 * @out_data: Buffer for returning a pointer to the response message
635 * Returns: 0 on success, 1 if more input data is needed, 2 if application data
636 * is available, or -1 on failure
637 *
638 * This function can be used to process TLS handshake messages. It reassembles
639 * the received fragments and uses a TLS library to process the messages. The
640 * response data from the TLS library is fragmented to suitable output messages
641 * that the caller can send out.
642 *
643 * out_data is used to return the response message if the return value of this
644 * function is 0, 2, or -1. In case of failure, the message is likely a TLS
645 * alarm message. The caller is responsible for freeing the allocated buffer if
646 * *out_data is not %NULL.
647 *
648 * This function is called for each received TLS message during the TLS
649 * handshake after eap_peer_tls_process_init() call and possible processing of
650 * TLS Flags field. Once the handshake has been completed, i.e., when
651 * tls_connection_established() returns 1, EAP method specific decrypting of
652 * the tunneled data is used.
653 */
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)654 int eap_peer_tls_process_helper(struct eap_sm *sm, struct eap_ssl_data *data,
655 EapType eap_type, int peap_version,
656 u8 id, const u8 *in_data, size_t in_len,
657 struct wpabuf **out_data)
658 {
659 int ret = 0;
660
661 *out_data = NULL;
662
663 if (data->tls_out && wpabuf_len(data->tls_out) > 0 && in_len > 0) {
664 wpa_printf(MSG_DEBUG, "SSL: Received non-ACK when output "
665 "fragments are waiting to be sent out");
666 return -1;
667 }
668
669 if (data->tls_out == NULL || wpabuf_len(data->tls_out) == 0) {
670 /*
671 * No more data to send out - expect to receive more data from
672 * the AS.
673 */
674 int res = eap_tls_process_input(sm, data, in_data, in_len,
675 out_data);
676 if (res) {
677 /*
678 * Input processing failed (res = -1) or more data is
679 * needed (res = 1).
680 */
681 return res;
682 }
683
684 /*
685 * The incoming message has been reassembled and processed. The
686 * response was allocated into data->tls_out buffer.
687 */
688 }
689
690 if (data->tls_out == NULL) {
691 /*
692 * No outgoing fragments remaining from the previous message
693 * and no new message generated. This indicates an error in TLS
694 * processing.
695 */
696 eap_peer_tls_reset_output(data);
697 return -1;
698 }
699
700 if (tls_connection_get_failed(data->ssl_ctx, data->conn)) {
701 /* TLS processing has failed - return error */
702 wpa_printf(MSG_DEBUG, "SSL: Failed - tls_out available to "
703 "report error");
704 ret = -1;
705 /* TODO: clean pin if engine used? */
706 }
707
708 if (data->tls_out == NULL || wpabuf_len(data->tls_out) == 0) {
709 /*
710 * TLS negotiation should now be complete since all other cases
711 * needing more data should have been caught above based on
712 * the TLS Message Length field.
713 */
714 wpa_printf(MSG_DEBUG, "SSL: No data to be sent out");
715 wpabuf_free(data->tls_out);
716 data->tls_out = NULL;
717 return 1;
718 }
719
720 /* Send the pending message (in fragments, if needed). */
721 return eap_tls_process_output(data, eap_type, peap_version, id, ret,
722 out_data);
723 }
724
725
726 /**
727 * eap_peer_tls_build_ack - Build a TLS ACK frame
728 * @id: EAP identifier for the response
729 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
730 * @peap_version: Version number for EAP-PEAP/TTLS
731 * Returns: Pointer to the allocated ACK frame or %NULL on failure
732 */
eap_peer_tls_build_ack(u8 id,EapType eap_type,int peap_version)733 struct wpabuf * eap_peer_tls_build_ack(u8 id, EapType eap_type,
734 int peap_version)
735 {
736 struct wpabuf *resp;
737
738 resp = eap_tls_msg_alloc(eap_type, 1, EAP_CODE_RESPONSE, id);
739 if (resp == NULL)
740 return NULL;
741 wpa_printf(MSG_DEBUG, "SSL: Building ACK (type=%d id=%d ver=%d)",
742 (int) eap_type, id, peap_version);
743 wpabuf_put_u8(resp, peap_version); /* Flags */
744 return resp;
745 }
746
747
748 /**
749 * eap_peer_tls_reauth_init - Re-initialize shared TLS for session resumption
750 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
751 * @data: Data for TLS processing
752 * Returns: 0 on success, -1 on failure
753 */
eap_peer_tls_reauth_init(struct eap_sm * sm,struct eap_ssl_data * data)754 int eap_peer_tls_reauth_init(struct eap_sm *sm, struct eap_ssl_data *data)
755 {
756 eap_peer_tls_reset_input(data);
757 eap_peer_tls_reset_output(data);
758 return tls_connection_shutdown(data->ssl_ctx, data->conn);
759 }
760
761
762 /**
763 * eap_peer_tls_status - Get TLS status
764 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
765 * @data: Data for TLS processing
766 * @buf: Buffer for status information
767 * @buflen: Maximum buffer length
768 * @verbose: Whether to include verbose status information
769 * Returns: Number of bytes written to buf.
770 */
eap_peer_tls_status(struct eap_sm * sm,struct eap_ssl_data * data,char * buf,size_t buflen,int verbose)771 int eap_peer_tls_status(struct eap_sm *sm, struct eap_ssl_data *data,
772 char *buf, size_t buflen, int verbose)
773 {
774 char name[128];
775 int len = 0, ret;
776
777 if (tls_get_cipher(data->ssl_ctx, data->conn, name, sizeof(name)) == 0)
778 {
779 ret = os_snprintf(buf + len, buflen - len,
780 "EAP TLS cipher=%s\n", name);
781 if (ret < 0 || (size_t) ret >= buflen - len)
782 return len;
783 len += ret;
784 }
785
786 return len;
787 }
788
789
790 /**
791 * eap_peer_tls_process_init - Initial validation/processing of EAP requests
792 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
793 * @data: Data for TLS processing
794 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
795 * @ret: Return values from EAP request validation and processing
796 * @reqData: EAP request to be processed (eapReqData)
797 * @len: Buffer for returning length of the remaining payload
798 * @flags: Buffer for returning TLS flags
799 * Returns: Pointer to payload after TLS flags and length or %NULL on failure
800 *
801 * This function validates the EAP header and processes the optional TLS
802 * Message Length field. If this is the first fragment of a TLS message, the
803 * TLS reassembly code is initialized to receive the indicated number of bytes.
804 *
805 * EAP-TLS, EAP-PEAP, EAP-TTLS, and EAP-FAST methods are expected to use this
806 * function as the first step in processing received messages. They will need
807 * to process the flags (apart from Message Length Included) that are returned
808 * through the flags pointer and the message payload that will be returned (and
809 * the length is returned through the len pointer). Return values (ret) are set
810 * for continuation of EAP method processing. The caller is responsible for
811 * setting these to indicate completion (either success or failure) based on
812 * the authentication result.
813 */
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)814 const u8 * eap_peer_tls_process_init(struct eap_sm *sm,
815 struct eap_ssl_data *data,
816 EapType eap_type,
817 struct eap_method_ret *ret,
818 const struct wpabuf *reqData,
819 size_t *len, u8 *flags)
820 {
821 const u8 *pos;
822 size_t left;
823 unsigned int tls_msg_len;
824
825 if (tls_get_errors(data->ssl_ctx)) {
826 wpa_printf(MSG_INFO, "SSL: TLS errors detected");
827 ret->ignore = TRUE;
828 return NULL;
829 }
830
831 if (eap_type == EAP_UNAUTH_TLS_TYPE)
832 pos = eap_hdr_validate(EAP_VENDOR_UNAUTH_TLS,
833 EAP_VENDOR_TYPE_UNAUTH_TLS, reqData,
834 &left);
835 else
836 pos = eap_hdr_validate(EAP_VENDOR_IETF, eap_type, reqData,
837 &left);
838 if (pos == NULL) {
839 ret->ignore = TRUE;
840 return NULL;
841 }
842 if (left == 0) {
843 wpa_printf(MSG_DEBUG, "SSL: Invalid TLS message: no Flags "
844 "octet included");
845 if (!sm->workaround) {
846 ret->ignore = TRUE;
847 return NULL;
848 }
849
850 wpa_printf(MSG_DEBUG, "SSL: Workaround - assume no Flags "
851 "indicates ACK frame");
852 *flags = 0;
853 } else {
854 *flags = *pos++;
855 left--;
856 }
857 wpa_printf(MSG_DEBUG, "SSL: Received packet(len=%lu) - "
858 "Flags 0x%02x", (unsigned long) wpabuf_len(reqData),
859 *flags);
860 if (*flags & EAP_TLS_FLAGS_LENGTH_INCLUDED) {
861 if (left < 4) {
862 wpa_printf(MSG_INFO, "SSL: Short frame with TLS "
863 "length");
864 ret->ignore = TRUE;
865 return NULL;
866 }
867 tls_msg_len = WPA_GET_BE32(pos);
868 wpa_printf(MSG_DEBUG, "SSL: TLS Message Length: %d",
869 tls_msg_len);
870 if (data->tls_in_left == 0) {
871 data->tls_in_total = tls_msg_len;
872 data->tls_in_left = tls_msg_len;
873 wpabuf_free(data->tls_in);
874 data->tls_in = NULL;
875 }
876 pos += 4;
877 left -= 4;
878
879 if (left > tls_msg_len) {
880 wpa_printf(MSG_INFO, "SSL: TLS Message Length (%d "
881 "bytes) smaller than this fragment (%d "
882 "bytes)", (int) tls_msg_len, (int) left);
883 ret->ignore = TRUE;
884 return NULL;
885 }
886 }
887
888 ret->ignore = FALSE;
889 ret->methodState = METHOD_MAY_CONT;
890 ret->decision = DECISION_FAIL;
891 ret->allowNotifications = TRUE;
892
893 *len = left;
894 return pos;
895 }
896
897
898 /**
899 * eap_peer_tls_reset_input - Reset input buffers
900 * @data: Data for TLS processing
901 *
902 * This function frees any allocated memory for input buffers and resets input
903 * state.
904 */
eap_peer_tls_reset_input(struct eap_ssl_data * data)905 void eap_peer_tls_reset_input(struct eap_ssl_data *data)
906 {
907 data->tls_in_left = data->tls_in_total = 0;
908 wpabuf_free(data->tls_in);
909 data->tls_in = NULL;
910 }
911
912
913 /**
914 * eap_peer_tls_reset_output - Reset output buffers
915 * @data: Data for TLS processing
916 *
917 * This function frees any allocated memory for output buffers and resets
918 * output state.
919 */
eap_peer_tls_reset_output(struct eap_ssl_data * data)920 void eap_peer_tls_reset_output(struct eap_ssl_data *data)
921 {
922 data->tls_out_pos = 0;
923 wpabuf_free(data->tls_out);
924 data->tls_out = NULL;
925 }
926
927
928 /**
929 * eap_peer_tls_decrypt - Decrypt received phase 2 TLS message
930 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
931 * @data: Data for TLS processing
932 * @in_data: Message received from the server
933 * @in_decrypted: Buffer for returning a pointer to the decrypted message
934 * Returns: 0 on success, 1 if more input data is needed, or -1 on failure
935 */
eap_peer_tls_decrypt(struct eap_sm * sm,struct eap_ssl_data * data,const struct wpabuf * in_data,struct wpabuf ** in_decrypted)936 int eap_peer_tls_decrypt(struct eap_sm *sm, struct eap_ssl_data *data,
937 const struct wpabuf *in_data,
938 struct wpabuf **in_decrypted)
939 {
940 const struct wpabuf *msg;
941 int need_more_input;
942
943 msg = eap_peer_tls_data_reassemble(data, in_data, &need_more_input);
944 if (msg == NULL)
945 return need_more_input ? 1 : -1;
946
947 *in_decrypted = tls_connection_decrypt(data->ssl_ctx, data->conn, msg);
948 eap_peer_tls_reset_input(data);
949 if (*in_decrypted == NULL) {
950 wpa_printf(MSG_INFO, "SSL: Failed to decrypt Phase 2 data");
951 return -1;
952 }
953 return 0;
954 }
955
956
957 /**
958 * eap_peer_tls_encrypt - Encrypt phase 2 TLS message
959 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
960 * @data: Data for TLS processing
961 * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
962 * @peap_version: Version number for EAP-PEAP/TTLS
963 * @id: EAP identifier for the response
964 * @in_data: Plaintext phase 2 data to encrypt or %NULL to continue fragments
965 * @out_data: Buffer for returning a pointer to the encrypted response message
966 * Returns: 0 on success, -1 on failure
967 */
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)968 int eap_peer_tls_encrypt(struct eap_sm *sm, struct eap_ssl_data *data,
969 EapType eap_type, int peap_version, u8 id,
970 const struct wpabuf *in_data,
971 struct wpabuf **out_data)
972 {
973 if (in_data) {
974 eap_peer_tls_reset_output(data);
975 data->tls_out = tls_connection_encrypt(data->ssl_ctx,
976 data->conn, in_data);
977 if (data->tls_out == NULL) {
978 wpa_printf(MSG_INFO, "SSL: Failed to encrypt Phase 2 "
979 "data (in_len=%lu)",
980 (unsigned long) wpabuf_len(in_data));
981 eap_peer_tls_reset_output(data);
982 return -1;
983 }
984 }
985
986 return eap_tls_process_output(data, eap_type, peap_version, id, 0,
987 out_data);
988 }
989
990
991 /**
992 * eap_peer_select_phase2_methods - Select phase 2 EAP method
993 * @config: Pointer to the network configuration
994 * @prefix: 'phase2' configuration prefix, e.g., "auth="
995 * @types: Buffer for returning allocated list of allowed EAP methods
996 * @num_types: Buffer for returning number of allocated EAP methods
997 * Returns: 0 on success, -1 on failure
998 *
999 * This function is used to parse EAP method list and select allowed methods
1000 * for Phase2 authentication.
1001 */
eap_peer_select_phase2_methods(struct eap_peer_config * config,const char * prefix,struct eap_method_type ** types,size_t * num_types)1002 int eap_peer_select_phase2_methods(struct eap_peer_config *config,
1003 const char *prefix,
1004 struct eap_method_type **types,
1005 size_t *num_types)
1006 {
1007 char *start, *pos, *buf;
1008 struct eap_method_type *methods = NULL, *_methods;
1009 u8 method;
1010 size_t num_methods = 0, prefix_len;
1011
1012 if (config == NULL || config->phase2 == NULL)
1013 goto get_defaults;
1014
1015 start = buf = os_strdup(config->phase2);
1016 if (buf == NULL)
1017 return -1;
1018
1019 prefix_len = os_strlen(prefix);
1020
1021 while (start && *start != '\0') {
1022 int vendor;
1023 pos = os_strstr(start, prefix);
1024 if (pos == NULL)
1025 break;
1026 if (start != pos && *(pos - 1) != ' ') {
1027 start = pos + prefix_len;
1028 continue;
1029 }
1030
1031 start = pos + prefix_len;
1032 pos = os_strchr(start, ' ');
1033 if (pos)
1034 *pos++ = '\0';
1035 method = eap_get_phase2_type(start, &vendor);
1036 if (vendor == EAP_VENDOR_IETF && method == EAP_TYPE_NONE) {
1037 wpa_printf(MSG_ERROR, "TLS: Unsupported Phase2 EAP "
1038 "method '%s'", start);
1039 } else {
1040 num_methods++;
1041 _methods = os_realloc_array(methods, num_methods,
1042 sizeof(*methods));
1043 if (_methods == NULL) {
1044 os_free(methods);
1045 os_free(buf);
1046 return -1;
1047 }
1048 methods = _methods;
1049 methods[num_methods - 1].vendor = vendor;
1050 methods[num_methods - 1].method = method;
1051 }
1052
1053 start = pos;
1054 }
1055
1056 os_free(buf);
1057
1058 get_defaults:
1059 if (methods == NULL)
1060 methods = eap_get_phase2_types(config, &num_methods);
1061
1062 if (methods == NULL) {
1063 wpa_printf(MSG_ERROR, "TLS: No Phase2 EAP methods available");
1064 return -1;
1065 }
1066 wpa_hexdump(MSG_DEBUG, "TLS: Phase2 EAP types",
1067 (u8 *) methods,
1068 num_methods * sizeof(struct eap_method_type));
1069
1070 *types = methods;
1071 *num_types = num_methods;
1072
1073 return 0;
1074 }
1075
1076
1077 /**
1078 * eap_peer_tls_phase2_nak - Generate EAP-Nak for Phase 2
1079 * @types: Buffer for returning allocated list of allowed EAP methods
1080 * @num_types: Buffer for returning number of allocated EAP methods
1081 * @hdr: EAP-Request header (and the following EAP type octet)
1082 * @resp: Buffer for returning the EAP-Nak message
1083 * Returns: 0 on success, -1 on failure
1084 */
eap_peer_tls_phase2_nak(struct eap_method_type * types,size_t num_types,struct eap_hdr * hdr,struct wpabuf ** resp)1085 int eap_peer_tls_phase2_nak(struct eap_method_type *types, size_t num_types,
1086 struct eap_hdr *hdr, struct wpabuf **resp)
1087 {
1088 u8 *pos = (u8 *) (hdr + 1);
1089 size_t i;
1090
1091 /* TODO: add support for expanded Nak */
1092 wpa_printf(MSG_DEBUG, "TLS: Phase 2 Request: Nak type=%d", *pos);
1093 wpa_hexdump(MSG_DEBUG, "TLS: Allowed Phase2 EAP types",
1094 (u8 *) types, num_types * sizeof(struct eap_method_type));
1095 *resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_NAK, num_types,
1096 EAP_CODE_RESPONSE, hdr->identifier);
1097 if (*resp == NULL)
1098 return -1;
1099
1100 for (i = 0; i < num_types; i++) {
1101 if (types[i].vendor == EAP_VENDOR_IETF &&
1102 types[i].method < 256)
1103 wpabuf_put_u8(*resp, types[i].method);
1104 }
1105
1106 eap_update_len(*resp);
1107
1108 return 0;
1109 }
1110