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      1 /*
      2  * EAP peer: EAP-TLS/PEAP/TTLS/FAST common functions
      3  * Copyright (c) 2004-2013, Jouni Malinen <j (at) 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 
     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 	if (type == EAP_WFA_UNAUTH_TLS_TYPE)
     27 		return eap_msg_alloc(EAP_VENDOR_WFA_NEW,
     28 				     EAP_VENDOR_WFA_UNAUTH_TLS, payload_len,
     29 				     code, identifier);
     30 	return eap_msg_alloc(EAP_VENDOR_IETF, type, payload_len, code,
     31 			     identifier);
     32 }
     33 
     34 
     35 static int eap_tls_check_blob(struct eap_sm *sm, const char **name,
     36 			      const u8 **data, size_t *data_len)
     37 {
     38 	const struct wpa_config_blob *blob;
     39 
     40 	if (*name == NULL || os_strncmp(*name, "blob://", 7) != 0)
     41 		return 0;
     42 
     43 	blob = eap_get_config_blob(sm, *name + 7);
     44 	if (blob == NULL) {
     45 		wpa_printf(MSG_ERROR, "%s: Named configuration blob '%s' not "
     46 			   "found", __func__, *name + 7);
     47 		return -1;
     48 	}
     49 
     50 	*name = NULL;
     51 	*data = blob->data;
     52 	*data_len = blob->len;
     53 
     54 	return 0;
     55 }
     56 
     57 
     58 static void eap_tls_params_flags(struct tls_connection_params *params,
     59 				 const char *txt)
     60 {
     61 	if (txt == NULL)
     62 		return;
     63 	if (os_strstr(txt, "tls_allow_md5=1"))
     64 		params->flags |= TLS_CONN_ALLOW_SIGN_RSA_MD5;
     65 	if (os_strstr(txt, "tls_disable_time_checks=1"))
     66 		params->flags |= TLS_CONN_DISABLE_TIME_CHECKS;
     67 	if (os_strstr(txt, "tls_disable_session_ticket=1"))
     68 		params->flags |= TLS_CONN_DISABLE_SESSION_TICKET;
     69 	if (os_strstr(txt, "tls_disable_session_ticket=0"))
     70 		params->flags &= ~TLS_CONN_DISABLE_SESSION_TICKET;
     71 	if (os_strstr(txt, "tls_disable_tlsv1_1=1"))
     72 		params->flags |= TLS_CONN_DISABLE_TLSv1_1;
     73 	if (os_strstr(txt, "tls_disable_tlsv1_1=0"))
     74 		params->flags &= ~TLS_CONN_DISABLE_TLSv1_1;
     75 	if (os_strstr(txt, "tls_disable_tlsv1_2=1"))
     76 		params->flags |= TLS_CONN_DISABLE_TLSv1_2;
     77 	if (os_strstr(txt, "tls_disable_tlsv1_2=0"))
     78 		params->flags &= ~TLS_CONN_DISABLE_TLSv1_2;
     79 }
     80 
     81 
     82 static void eap_tls_params_from_conf1(struct tls_connection_params *params,
     83 				      struct eap_peer_config *config)
     84 {
     85 	params->ca_cert = (char *) config->ca_cert;
     86 	params->ca_path = (char *) config->ca_path;
     87 	params->client_cert = (char *) config->client_cert;
     88 	params->private_key = (char *) config->private_key;
     89 	params->private_key_passwd = (char *) config->private_key_passwd;
     90 	params->dh_file = (char *) config->dh_file;
     91 	params->subject_match = (char *) config->subject_match;
     92 	params->altsubject_match = (char *) config->altsubject_match;
     93 	params->suffix_match = config->domain_suffix_match;
     94 	params->domain_match = config->domain_match;
     95 	params->engine = config->engine;
     96 	params->engine_id = config->engine_id;
     97 	params->pin = config->pin;
     98 	params->key_id = config->key_id;
     99 	params->cert_id = config->cert_id;
    100 	params->ca_cert_id = config->ca_cert_id;
    101 	eap_tls_params_flags(params, config->phase1);
    102 }
    103 
    104 
    105 static void eap_tls_params_from_conf2(struct tls_connection_params *params,
    106 				      struct eap_peer_config *config)
    107 {
    108 	params->ca_cert = (char *) config->ca_cert2;
    109 	params->ca_path = (char *) config->ca_path2;
    110 	params->client_cert = (char *) config->client_cert2;
    111 	params->private_key = (char *) config->private_key2;
    112 	params->private_key_passwd = (char *) config->private_key2_passwd;
    113 	params->dh_file = (char *) config->dh_file2;
    114 	params->subject_match = (char *) config->subject_match2;
    115 	params->altsubject_match = (char *) config->altsubject_match2;
    116 	params->suffix_match = config->domain_suffix_match2;
    117 	params->domain_match = config->domain_match2;
    118 	params->engine = config->engine2;
    119 	params->engine_id = config->engine2_id;
    120 	params->pin = config->pin2;
    121 	params->key_id = config->key2_id;
    122 	params->cert_id = config->cert2_id;
    123 	params->ca_cert_id = config->ca_cert2_id;
    124 	eap_tls_params_flags(params, config->phase2);
    125 }
    126 
    127 
    128 static int eap_tls_params_from_conf(struct eap_sm *sm,
    129 				    struct eap_ssl_data *data,
    130 				    struct tls_connection_params *params,
    131 				    struct eap_peer_config *config, int phase2)
    132 {
    133 	os_memset(params, 0, sizeof(*params));
    134 	if (sm->workaround && data->eap_type != EAP_TYPE_FAST) {
    135 		/*
    136 		 * Some deployed authentication servers seem to be unable to
    137 		 * handle the TLS Session Ticket extension (they are supposed
    138 		 * to ignore unrecognized TLS extensions, but end up rejecting
    139 		 * the ClientHello instead). As a workaround, disable use of
    140 		 * TLS Sesson Ticket extension for EAP-TLS, EAP-PEAP, and
    141 		 * EAP-TTLS (EAP-FAST uses session ticket, so any server that
    142 		 * supports EAP-FAST does not need this workaround).
    143 		 */
    144 		params->flags |= TLS_CONN_DISABLE_SESSION_TICKET;
    145 	}
    146 	if (phase2) {
    147 		wpa_printf(MSG_DEBUG, "TLS: using phase2 config options");
    148 		eap_tls_params_from_conf2(params, config);
    149 	} else {
    150 		wpa_printf(MSG_DEBUG, "TLS: using phase1 config options");
    151 		eap_tls_params_from_conf1(params, config);
    152 		if (data->eap_type == EAP_TYPE_FAST)
    153 			params->flags |= TLS_CONN_EAP_FAST;
    154 	}
    155 
    156 	/*
    157 	 * Use blob data, if available. Otherwise, leave reference to external
    158 	 * file as-is.
    159 	 */
    160 	if (eap_tls_check_blob(sm, &params->ca_cert, &params->ca_cert_blob,
    161 			       &params->ca_cert_blob_len) ||
    162 	    eap_tls_check_blob(sm, &params->client_cert,
    163 			       &params->client_cert_blob,
    164 			       &params->client_cert_blob_len) ||
    165 	    eap_tls_check_blob(sm, &params->private_key,
    166 			       &params->private_key_blob,
    167 			       &params->private_key_blob_len) ||
    168 	    eap_tls_check_blob(sm, &params->dh_file, &params->dh_blob,
    169 			       &params->dh_blob_len)) {
    170 		wpa_printf(MSG_INFO, "SSL: Failed to get configuration blobs");
    171 		return -1;
    172 	}
    173 
    174 	params->openssl_ciphers = config->openssl_ciphers;
    175 
    176 	return 0;
    177 }
    178 
    179 
    180 static int eap_tls_init_connection(struct eap_sm *sm,
    181 				   struct eap_ssl_data *data,
    182 				   struct eap_peer_config *config,
    183 				   struct tls_connection_params *params)
    184 {
    185 	int res;
    186 
    187 	if (config->ocsp)
    188 		params->flags |= TLS_CONN_REQUEST_OCSP;
    189 	if (config->ocsp == 2)
    190 		params->flags |= TLS_CONN_REQUIRE_OCSP;
    191 	data->conn = tls_connection_init(data->ssl_ctx);
    192 	if (data->conn == NULL) {
    193 		wpa_printf(MSG_INFO, "SSL: Failed to initialize new TLS "
    194 			   "connection");
    195 		return -1;
    196 	}
    197 
    198 	res = tls_connection_set_params(data->ssl_ctx, data->conn, params);
    199 	if (res == TLS_SET_PARAMS_ENGINE_PRV_BAD_PIN) {
    200 		/*
    201 		 * At this point with the pkcs11 engine the PIN is wrong. We
    202 		 * reset the PIN in the configuration to be sure to not use it
    203 		 * again and the calling function must request a new one.
    204 		 */
    205 		wpa_printf(MSG_INFO,
    206 			   "TLS: Bad PIN provided, requesting a new one");
    207 		os_free(config->pin);
    208 		config->pin = NULL;
    209 		eap_sm_request_pin(sm);
    210 		sm->ignore = TRUE;
    211 	} else if (res == TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED) {
    212 		wpa_printf(MSG_INFO, "TLS: Failed to initialize engine");
    213 	} else if (res == TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED) {
    214 		wpa_printf(MSG_INFO, "TLS: Failed to load private key");
    215 		sm->ignore = TRUE;
    216 	}
    217 	if (res) {
    218 		wpa_printf(MSG_INFO, "TLS: Failed to set TLS connection "
    219 			   "parameters");
    220 		tls_connection_deinit(data->ssl_ctx, data->conn);
    221 		data->conn = NULL;
    222 		return -1;
    223 	}
    224 
    225 	return 0;
    226 }
    227 
    228 
    229 /**
    230  * eap_peer_tls_ssl_init - Initialize shared TLS functionality
    231  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    232  * @data: Data for TLS processing
    233  * @config: Pointer to the network configuration
    234  * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
    235  * Returns: 0 on success, -1 on failure
    236  *
    237  * This function is used to initialize shared TLS functionality for EAP-TLS,
    238  * EAP-PEAP, EAP-TTLS, and EAP-FAST.
    239  */
    240 int eap_peer_tls_ssl_init(struct eap_sm *sm, struct eap_ssl_data *data,
    241 			  struct eap_peer_config *config, u8 eap_type)
    242 {
    243 	struct tls_connection_params params;
    244 
    245 	if (config == NULL)
    246 		return -1;
    247 
    248 	data->eap = sm;
    249 	data->eap_type = eap_type;
    250 	data->phase2 = sm->init_phase2;
    251 	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
    252 		sm->ssl_ctx;
    253 	if (eap_tls_params_from_conf(sm, data, &params, config, data->phase2) <
    254 	    0)
    255 		return -1;
    256 
    257 	if (eap_tls_init_connection(sm, data, config, &params) < 0)
    258 		return -1;
    259 
    260 	data->tls_out_limit = config->fragment_size;
    261 	if (data->phase2) {
    262 		/* Limit the fragment size in the inner TLS authentication
    263 		 * since the outer authentication with EAP-PEAP does not yet
    264 		 * support fragmentation */
    265 		if (data->tls_out_limit > 100)
    266 			data->tls_out_limit -= 100;
    267 	}
    268 
    269 	if (config->phase1 &&
    270 	    os_strstr(config->phase1, "include_tls_length=1")) {
    271 		wpa_printf(MSG_DEBUG, "TLS: Include TLS Message Length in "
    272 			   "unfragmented packets");
    273 		data->include_tls_length = 1;
    274 	}
    275 
    276 	return 0;
    277 }
    278 
    279 
    280 /**
    281  * eap_peer_tls_ssl_deinit - Deinitialize shared TLS functionality
    282  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    283  * @data: Data for TLS processing
    284  *
    285  * This function deinitializes shared TLS functionality that was initialized
    286  * with eap_peer_tls_ssl_init().
    287  */
    288 void eap_peer_tls_ssl_deinit(struct eap_sm *sm, struct eap_ssl_data *data)
    289 {
    290 	tls_connection_deinit(data->ssl_ctx, data->conn);
    291 	eap_peer_tls_reset_input(data);
    292 	eap_peer_tls_reset_output(data);
    293 }
    294 
    295 
    296 /**
    297  * eap_peer_tls_derive_key - Derive a key based on TLS session data
    298  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    299  * @data: Data for TLS processing
    300  * @label: Label string for deriving the keys, e.g., "client EAP encryption"
    301  * @len: Length of the key material to generate (usually 64 for MSK)
    302  * Returns: Pointer to allocated key on success or %NULL on failure
    303  *
    304  * This function uses TLS-PRF to generate pseudo-random data based on the TLS
    305  * session data (client/server random and master key). Each key type may use a
    306  * different label to bind the key usage into the generated material.
    307  *
    308  * The caller is responsible for freeing the returned buffer.
    309  */
    310 u8 * eap_peer_tls_derive_key(struct eap_sm *sm, struct eap_ssl_data *data,
    311 			     const char *label, size_t len)
    312 {
    313 	u8 *out;
    314 
    315 	out = os_malloc(len);
    316 	if (out == NULL)
    317 		return NULL;
    318 
    319 	if (tls_connection_prf(data->ssl_ctx, data->conn, label, 0, 0,
    320 			       out, len)) {
    321 		os_free(out);
    322 		return NULL;
    323 	}
    324 
    325 	return out;
    326 }
    327 
    328 
    329 /**
    330  * eap_peer_tls_derive_session_id - Derive a Session-Id based on TLS data
    331  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    332  * @data: Data for TLS processing
    333  * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
    334  * @len: Pointer to length of the session ID generated
    335  * Returns: Pointer to allocated Session-Id on success or %NULL on failure
    336  *
    337  * This function derive the Session-Id based on the TLS session data
    338  * (client/server random and method type).
    339  *
    340  * The caller is responsible for freeing the returned buffer.
    341  */
    342 u8 * eap_peer_tls_derive_session_id(struct eap_sm *sm,
    343 				    struct eap_ssl_data *data, u8 eap_type,
    344 				    size_t *len)
    345 {
    346 	struct tls_keys keys;
    347 	u8 *out;
    348 
    349 	if (tls_connection_get_keys(sm->ssl_ctx, data->conn, &keys))
    350 		return NULL;
    351 
    352 	if (keys.client_random == NULL || keys.server_random == NULL)
    353 		return NULL;
    354 
    355 	*len = 1 + keys.client_random_len + keys.server_random_len;
    356 	out = os_malloc(*len);
    357 	if (out == NULL)
    358 		return NULL;
    359 
    360 	/* Session-Id = EAP type || client.random || server.random */
    361 	out[0] = eap_type;
    362 	os_memcpy(out + 1, keys.client_random, keys.client_random_len);
    363 	os_memcpy(out + 1 + keys.client_random_len, keys.server_random,
    364 		  keys.server_random_len);
    365 
    366 	return out;
    367 }
    368 
    369 
    370 /**
    371  * eap_peer_tls_reassemble_fragment - Reassemble a received fragment
    372  * @data: Data for TLS processing
    373  * @in_data: Next incoming TLS segment
    374  * Returns: 0 on success, 1 if more data is needed for the full message, or
    375  * -1 on error
    376  */
    377 static int eap_peer_tls_reassemble_fragment(struct eap_ssl_data *data,
    378 					    const struct wpabuf *in_data)
    379 {
    380 	size_t tls_in_len, in_len;
    381 
    382 	tls_in_len = data->tls_in ? wpabuf_len(data->tls_in) : 0;
    383 	in_len = in_data ? wpabuf_len(in_data) : 0;
    384 
    385 	if (tls_in_len + in_len == 0) {
    386 		/* No message data received?! */
    387 		wpa_printf(MSG_WARNING, "SSL: Invalid reassembly state: "
    388 			   "tls_in_left=%lu tls_in_len=%lu in_len=%lu",
    389 			   (unsigned long) data->tls_in_left,
    390 			   (unsigned long) tls_in_len,
    391 			   (unsigned long) in_len);
    392 		eap_peer_tls_reset_input(data);
    393 		return -1;
    394 	}
    395 
    396 	if (tls_in_len + in_len > 65536) {
    397 		/*
    398 		 * Limit length to avoid rogue servers from causing large
    399 		 * memory allocations.
    400 		 */
    401 		wpa_printf(MSG_INFO, "SSL: Too long TLS fragment (size over "
    402 			   "64 kB)");
    403 		eap_peer_tls_reset_input(data);
    404 		return -1;
    405 	}
    406 
    407 	if (in_len > data->tls_in_left) {
    408 		/* Sender is doing something odd - reject message */
    409 		wpa_printf(MSG_INFO, "SSL: more data than TLS message length "
    410 			   "indicated");
    411 		eap_peer_tls_reset_input(data);
    412 		return -1;
    413 	}
    414 
    415 	if (wpabuf_resize(&data->tls_in, in_len) < 0) {
    416 		wpa_printf(MSG_INFO, "SSL: Could not allocate memory for TLS "
    417 			   "data");
    418 		eap_peer_tls_reset_input(data);
    419 		return -1;
    420 	}
    421 	if (in_data)
    422 		wpabuf_put_buf(data->tls_in, in_data);
    423 	data->tls_in_left -= in_len;
    424 
    425 	if (data->tls_in_left > 0) {
    426 		wpa_printf(MSG_DEBUG, "SSL: Need %lu bytes more input "
    427 			   "data", (unsigned long) data->tls_in_left);
    428 		return 1;
    429 	}
    430 
    431 	return 0;
    432 }
    433 
    434 
    435 /**
    436  * eap_peer_tls_data_reassemble - Reassemble TLS data
    437  * @data: Data for TLS processing
    438  * @in_data: Next incoming TLS segment
    439  * @need_more_input: Variable for returning whether more input data is needed
    440  * to reassemble this TLS packet
    441  * Returns: Pointer to output data, %NULL on error or when more data is needed
    442  * for the full message (in which case, *need_more_input is also set to 1).
    443  *
    444  * This function reassembles TLS fragments. Caller must not free the returned
    445  * data buffer since an internal pointer to it is maintained.
    446  */
    447 static const struct wpabuf * eap_peer_tls_data_reassemble(
    448 	struct eap_ssl_data *data, const struct wpabuf *in_data,
    449 	int *need_more_input)
    450 {
    451 	*need_more_input = 0;
    452 
    453 	if (data->tls_in_left > wpabuf_len(in_data) || data->tls_in) {
    454 		/* Message has fragments */
    455 		int res = eap_peer_tls_reassemble_fragment(data, in_data);
    456 		if (res) {
    457 			if (res == 1)
    458 				*need_more_input = 1;
    459 			return NULL;
    460 		}
    461 
    462 		/* Message is now fully reassembled. */
    463 	} else {
    464 		/* No fragments in this message, so just make a copy of it. */
    465 		data->tls_in_left = 0;
    466 		data->tls_in = wpabuf_dup(in_data);
    467 		if (data->tls_in == NULL)
    468 			return NULL;
    469 	}
    470 
    471 	return data->tls_in;
    472 }
    473 
    474 
    475 /**
    476  * eap_tls_process_input - Process incoming TLS message
    477  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    478  * @data: Data for TLS processing
    479  * @in_data: Message received from the server
    480  * @out_data: Buffer for returning a pointer to application data (if available)
    481  * Returns: 0 on success, 1 if more input data is needed, 2 if application data
    482  * is available, -1 on failure
    483  */
    484 static int eap_tls_process_input(struct eap_sm *sm, struct eap_ssl_data *data,
    485 				 const struct wpabuf *in_data,
    486 				 struct wpabuf **out_data)
    487 {
    488 	const struct wpabuf *msg;
    489 	int need_more_input;
    490 	struct wpabuf *appl_data;
    491 
    492 	msg = eap_peer_tls_data_reassemble(data, in_data, &need_more_input);
    493 	if (msg == NULL)
    494 		return need_more_input ? 1 : -1;
    495 
    496 	/* Full TLS message reassembled - continue handshake processing */
    497 	if (data->tls_out) {
    498 		/* This should not happen.. */
    499 		wpa_printf(MSG_INFO, "SSL: eap_tls_process_input - pending "
    500 			   "tls_out data even though tls_out_len = 0");
    501 		wpabuf_free(data->tls_out);
    502 		WPA_ASSERT(data->tls_out == NULL);
    503 	}
    504 	appl_data = NULL;
    505 	data->tls_out = tls_connection_handshake(data->ssl_ctx, data->conn,
    506 						 msg, &appl_data);
    507 
    508 	eap_peer_tls_reset_input(data);
    509 
    510 	if (appl_data &&
    511 	    tls_connection_established(data->ssl_ctx, data->conn) &&
    512 	    !tls_connection_get_failed(data->ssl_ctx, data->conn)) {
    513 		wpa_hexdump_buf_key(MSG_MSGDUMP, "SSL: Application data",
    514 				    appl_data);
    515 		*out_data = appl_data;
    516 		return 2;
    517 	}
    518 
    519 	wpabuf_free(appl_data);
    520 
    521 	return 0;
    522 }
    523 
    524 
    525 /**
    526  * eap_tls_process_output - Process outgoing TLS message
    527  * @data: Data for TLS processing
    528  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    529  * @peap_version: Version number for EAP-PEAP/TTLS
    530  * @id: EAP identifier for the response
    531  * @ret: Return value to use on success
    532  * @out_data: Buffer for returning the allocated output buffer
    533  * Returns: ret (0 or 1) on success, -1 on failure
    534  */
    535 static int eap_tls_process_output(struct eap_ssl_data *data, EapType eap_type,
    536 				  int peap_version, u8 id, int ret,
    537 				  struct wpabuf **out_data)
    538 {
    539 	size_t len;
    540 	u8 *flags;
    541 	int more_fragments, length_included;
    542 
    543 	if (data->tls_out == NULL)
    544 		return -1;
    545 	len = wpabuf_len(data->tls_out) - data->tls_out_pos;
    546 	wpa_printf(MSG_DEBUG, "SSL: %lu bytes left to be sent out (of total "
    547 		   "%lu bytes)",
    548 		   (unsigned long) len,
    549 		   (unsigned long) wpabuf_len(data->tls_out));
    550 
    551 	/*
    552 	 * Limit outgoing message to the configured maximum size. Fragment
    553 	 * message if needed.
    554 	 */
    555 	if (len > data->tls_out_limit) {
    556 		more_fragments = 1;
    557 		len = data->tls_out_limit;
    558 		wpa_printf(MSG_DEBUG, "SSL: sending %lu bytes, more fragments "
    559 			   "will follow", (unsigned long) len);
    560 	} else
    561 		more_fragments = 0;
    562 
    563 	length_included = data->tls_out_pos == 0 &&
    564 		(wpabuf_len(data->tls_out) > data->tls_out_limit ||
    565 		 data->include_tls_length);
    566 	if (!length_included &&
    567 	    eap_type == EAP_TYPE_PEAP && peap_version == 0 &&
    568 	    !tls_connection_established(data->eap->ssl_ctx, data->conn)) {
    569 		/*
    570 		 * Windows Server 2008 NPS really wants to have the TLS Message
    571 		 * length included in phase 0 even for unfragmented frames or
    572 		 * it will get very confused with Compound MAC calculation and
    573 		 * Outer TLVs.
    574 		 */
    575 		length_included = 1;
    576 	}
    577 
    578 	*out_data = eap_tls_msg_alloc(eap_type, 1 + length_included * 4 + len,
    579 				      EAP_CODE_RESPONSE, id);
    580 	if (*out_data == NULL)
    581 		return -1;
    582 
    583 	flags = wpabuf_put(*out_data, 1);
    584 	*flags = peap_version;
    585 	if (more_fragments)
    586 		*flags |= EAP_TLS_FLAGS_MORE_FRAGMENTS;
    587 	if (length_included) {
    588 		*flags |= EAP_TLS_FLAGS_LENGTH_INCLUDED;
    589 		wpabuf_put_be32(*out_data, wpabuf_len(data->tls_out));
    590 	}
    591 
    592 	wpabuf_put_data(*out_data,
    593 			wpabuf_head_u8(data->tls_out) + data->tls_out_pos,
    594 			len);
    595 	data->tls_out_pos += len;
    596 
    597 	if (!more_fragments)
    598 		eap_peer_tls_reset_output(data);
    599 
    600 	return ret;
    601 }
    602 
    603 
    604 /**
    605  * eap_peer_tls_process_helper - Process TLS handshake message
    606  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    607  * @data: Data for TLS processing
    608  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    609  * @peap_version: Version number for EAP-PEAP/TTLS
    610  * @id: EAP identifier for the response
    611  * @in_data: Message received from the server
    612  * @out_data: Buffer for returning a pointer to the response message
    613  * Returns: 0 on success, 1 if more input data is needed, 2 if application data
    614  * is available, or -1 on failure
    615  *
    616  * This function can be used to process TLS handshake messages. It reassembles
    617  * the received fragments and uses a TLS library to process the messages. The
    618  * response data from the TLS library is fragmented to suitable output messages
    619  * that the caller can send out.
    620  *
    621  * out_data is used to return the response message if the return value of this
    622  * function is 0, 2, or -1. In case of failure, the message is likely a TLS
    623  * alarm message. The caller is responsible for freeing the allocated buffer if
    624  * *out_data is not %NULL.
    625  *
    626  * This function is called for each received TLS message during the TLS
    627  * handshake after eap_peer_tls_process_init() call and possible processing of
    628  * TLS Flags field. Once the handshake has been completed, i.e., when
    629  * tls_connection_established() returns 1, EAP method specific decrypting of
    630  * the tunneled data is used.
    631  */
    632 int eap_peer_tls_process_helper(struct eap_sm *sm, struct eap_ssl_data *data,
    633 				EapType eap_type, int peap_version,
    634 				u8 id, const struct wpabuf *in_data,
    635 				struct wpabuf **out_data)
    636 {
    637 	int ret = 0;
    638 
    639 	*out_data = NULL;
    640 
    641 	if (data->tls_out && wpabuf_len(data->tls_out) > 0 &&
    642 	    wpabuf_len(in_data) > 0) {
    643 		wpa_printf(MSG_DEBUG, "SSL: Received non-ACK when output "
    644 			   "fragments are waiting to be sent out");
    645 		return -1;
    646 	}
    647 
    648 	if (data->tls_out == NULL || wpabuf_len(data->tls_out) == 0) {
    649 		/*
    650 		 * No more data to send out - expect to receive more data from
    651 		 * the AS.
    652 		 */
    653 		int res = eap_tls_process_input(sm, data, in_data, out_data);
    654 		if (res) {
    655 			/*
    656 			 * Input processing failed (res = -1) or more data is
    657 			 * needed (res = 1).
    658 			 */
    659 			return res;
    660 		}
    661 
    662 		/*
    663 		 * The incoming message has been reassembled and processed. The
    664 		 * response was allocated into data->tls_out buffer.
    665 		 */
    666 	}
    667 
    668 	if (data->tls_out == NULL) {
    669 		/*
    670 		 * No outgoing fragments remaining from the previous message
    671 		 * and no new message generated. This indicates an error in TLS
    672 		 * processing.
    673 		 */
    674 		eap_peer_tls_reset_output(data);
    675 		return -1;
    676 	}
    677 
    678 	if (tls_connection_get_failed(data->ssl_ctx, data->conn)) {
    679 		/* TLS processing has failed - return error */
    680 		wpa_printf(MSG_DEBUG, "SSL: Failed - tls_out available to "
    681 			   "report error");
    682 		ret = -1;
    683 		/* TODO: clean pin if engine used? */
    684 	}
    685 
    686 	if (data->tls_out == NULL || wpabuf_len(data->tls_out) == 0) {
    687 		/*
    688 		 * TLS negotiation should now be complete since all other cases
    689 		 * needing more data should have been caught above based on
    690 		 * the TLS Message Length field.
    691 		 */
    692 		wpa_printf(MSG_DEBUG, "SSL: No data to be sent out");
    693 		wpabuf_free(data->tls_out);
    694 		data->tls_out = NULL;
    695 		return 1;
    696 	}
    697 
    698 	/* Send the pending message (in fragments, if needed). */
    699 	return eap_tls_process_output(data, eap_type, peap_version, id, ret,
    700 				      out_data);
    701 }
    702 
    703 
    704 /**
    705  * eap_peer_tls_build_ack - Build a TLS ACK frame
    706  * @id: EAP identifier for the response
    707  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    708  * @peap_version: Version number for EAP-PEAP/TTLS
    709  * Returns: Pointer to the allocated ACK frame or %NULL on failure
    710  */
    711 struct wpabuf * eap_peer_tls_build_ack(u8 id, EapType eap_type,
    712 				       int peap_version)
    713 {
    714 	struct wpabuf *resp;
    715 
    716 	resp = eap_tls_msg_alloc(eap_type, 1, EAP_CODE_RESPONSE, id);
    717 	if (resp == NULL)
    718 		return NULL;
    719 	wpa_printf(MSG_DEBUG, "SSL: Building ACK (type=%d id=%d ver=%d)",
    720 		   (int) eap_type, id, peap_version);
    721 	wpabuf_put_u8(resp, peap_version); /* Flags */
    722 	return resp;
    723 }
    724 
    725 
    726 /**
    727  * eap_peer_tls_reauth_init - Re-initialize shared TLS for session resumption
    728  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    729  * @data: Data for TLS processing
    730  * Returns: 0 on success, -1 on failure
    731  */
    732 int eap_peer_tls_reauth_init(struct eap_sm *sm, struct eap_ssl_data *data)
    733 {
    734 	eap_peer_tls_reset_input(data);
    735 	eap_peer_tls_reset_output(data);
    736 	return tls_connection_shutdown(data->ssl_ctx, data->conn);
    737 }
    738 
    739 
    740 /**
    741  * eap_peer_tls_status - Get TLS status
    742  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    743  * @data: Data for TLS processing
    744  * @buf: Buffer for status information
    745  * @buflen: Maximum buffer length
    746  * @verbose: Whether to include verbose status information
    747  * Returns: Number of bytes written to buf.
    748  */
    749 int eap_peer_tls_status(struct eap_sm *sm, struct eap_ssl_data *data,
    750 			char *buf, size_t buflen, int verbose)
    751 {
    752 	char name[128];
    753 	int len = 0, ret;
    754 
    755 	if (tls_get_cipher(data->ssl_ctx, data->conn, name, sizeof(name)) == 0)
    756 	{
    757 		ret = os_snprintf(buf + len, buflen - len,
    758 				  "EAP TLS cipher=%s\n"
    759 				  "tls_session_reused=%d\n",
    760 				  name, tls_connection_resumed(data->ssl_ctx,
    761 							       data->conn));
    762 		if (os_snprintf_error(buflen - len, ret))
    763 			return len;
    764 		len += ret;
    765 	}
    766 
    767 	return len;
    768 }
    769 
    770 
    771 /**
    772  * eap_peer_tls_process_init - Initial validation/processing of EAP requests
    773  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    774  * @data: Data for TLS processing
    775  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    776  * @ret: Return values from EAP request validation and processing
    777  * @reqData: EAP request to be processed (eapReqData)
    778  * @len: Buffer for returning length of the remaining payload
    779  * @flags: Buffer for returning TLS flags
    780  * Returns: Pointer to payload after TLS flags and length or %NULL on failure
    781  *
    782  * This function validates the EAP header and processes the optional TLS
    783  * Message Length field. If this is the first fragment of a TLS message, the
    784  * TLS reassembly code is initialized to receive the indicated number of bytes.
    785  *
    786  * EAP-TLS, EAP-PEAP, EAP-TTLS, and EAP-FAST methods are expected to use this
    787  * function as the first step in processing received messages. They will need
    788  * to process the flags (apart from Message Length Included) that are returned
    789  * through the flags pointer and the message payload that will be returned (and
    790  * the length is returned through the len pointer). Return values (ret) are set
    791  * for continuation of EAP method processing. The caller is responsible for
    792  * setting these to indicate completion (either success or failure) based on
    793  * the authentication result.
    794  */
    795 const u8 * eap_peer_tls_process_init(struct eap_sm *sm,
    796 				     struct eap_ssl_data *data,
    797 				     EapType eap_type,
    798 				     struct eap_method_ret *ret,
    799 				     const struct wpabuf *reqData,
    800 				     size_t *len, u8 *flags)
    801 {
    802 	const u8 *pos;
    803 	size_t left;
    804 	unsigned int tls_msg_len;
    805 
    806 	if (tls_get_errors(data->ssl_ctx)) {
    807 		wpa_printf(MSG_INFO, "SSL: TLS errors detected");
    808 		ret->ignore = TRUE;
    809 		return NULL;
    810 	}
    811 
    812 	if (eap_type == EAP_UNAUTH_TLS_TYPE)
    813 		pos = eap_hdr_validate(EAP_VENDOR_UNAUTH_TLS,
    814 				       EAP_VENDOR_TYPE_UNAUTH_TLS, reqData,
    815 				       &left);
    816 	else if (eap_type == EAP_WFA_UNAUTH_TLS_TYPE)
    817 		pos = eap_hdr_validate(EAP_VENDOR_WFA_NEW,
    818 				       EAP_VENDOR_WFA_UNAUTH_TLS, reqData,
    819 				       &left);
    820 	else
    821 		pos = eap_hdr_validate(EAP_VENDOR_IETF, eap_type, reqData,
    822 				       &left);
    823 	if (pos == NULL) {
    824 		ret->ignore = TRUE;
    825 		return NULL;
    826 	}
    827 	if (left == 0) {
    828 		wpa_printf(MSG_DEBUG, "SSL: Invalid TLS message: no Flags "
    829 			   "octet included");
    830 		if (!sm->workaround) {
    831 			ret->ignore = TRUE;
    832 			return NULL;
    833 		}
    834 
    835 		wpa_printf(MSG_DEBUG, "SSL: Workaround - assume no Flags "
    836 			   "indicates ACK frame");
    837 		*flags = 0;
    838 	} else {
    839 		*flags = *pos++;
    840 		left--;
    841 	}
    842 	wpa_printf(MSG_DEBUG, "SSL: Received packet(len=%lu) - "
    843 		   "Flags 0x%02x", (unsigned long) wpabuf_len(reqData),
    844 		   *flags);
    845 	if (*flags & EAP_TLS_FLAGS_LENGTH_INCLUDED) {
    846 		if (left < 4) {
    847 			wpa_printf(MSG_INFO, "SSL: Short frame with TLS "
    848 				   "length");
    849 			ret->ignore = TRUE;
    850 			return NULL;
    851 		}
    852 		tls_msg_len = WPA_GET_BE32(pos);
    853 		wpa_printf(MSG_DEBUG, "SSL: TLS Message Length: %d",
    854 			   tls_msg_len);
    855 		if (data->tls_in_left == 0) {
    856 			data->tls_in_total = tls_msg_len;
    857 			data->tls_in_left = tls_msg_len;
    858 			wpabuf_free(data->tls_in);
    859 			data->tls_in = NULL;
    860 		}
    861 		pos += 4;
    862 		left -= 4;
    863 
    864 		if (left > tls_msg_len) {
    865 			wpa_printf(MSG_INFO, "SSL: TLS Message Length (%d "
    866 				   "bytes) smaller than this fragment (%d "
    867 				   "bytes)", (int) tls_msg_len, (int) left);
    868 			ret->ignore = TRUE;
    869 			return NULL;
    870 		}
    871 	}
    872 
    873 	ret->ignore = FALSE;
    874 	ret->methodState = METHOD_MAY_CONT;
    875 	ret->decision = DECISION_FAIL;
    876 	ret->allowNotifications = TRUE;
    877 
    878 	*len = left;
    879 	return pos;
    880 }
    881 
    882 
    883 /**
    884  * eap_peer_tls_reset_input - Reset input buffers
    885  * @data: Data for TLS processing
    886  *
    887  * This function frees any allocated memory for input buffers and resets input
    888  * state.
    889  */
    890 void eap_peer_tls_reset_input(struct eap_ssl_data *data)
    891 {
    892 	data->tls_in_left = data->tls_in_total = 0;
    893 	wpabuf_free(data->tls_in);
    894 	data->tls_in = NULL;
    895 }
    896 
    897 
    898 /**
    899  * eap_peer_tls_reset_output - Reset output buffers
    900  * @data: Data for TLS processing
    901  *
    902  * This function frees any allocated memory for output buffers and resets
    903  * output state.
    904  */
    905 void eap_peer_tls_reset_output(struct eap_ssl_data *data)
    906 {
    907 	data->tls_out_pos = 0;
    908 	wpabuf_free(data->tls_out);
    909 	data->tls_out = NULL;
    910 }
    911 
    912 
    913 /**
    914  * eap_peer_tls_decrypt - Decrypt received phase 2 TLS message
    915  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    916  * @data: Data for TLS processing
    917  * @in_data: Message received from the server
    918  * @in_decrypted: Buffer for returning a pointer to the decrypted message
    919  * Returns: 0 on success, 1 if more input data is needed, or -1 on failure
    920  */
    921 int eap_peer_tls_decrypt(struct eap_sm *sm, struct eap_ssl_data *data,
    922 			 const struct wpabuf *in_data,
    923 			 struct wpabuf **in_decrypted)
    924 {
    925 	const struct wpabuf *msg;
    926 	int need_more_input;
    927 
    928 	msg = eap_peer_tls_data_reassemble(data, in_data, &need_more_input);
    929 	if (msg == NULL)
    930 		return need_more_input ? 1 : -1;
    931 
    932 	*in_decrypted = tls_connection_decrypt(data->ssl_ctx, data->conn, msg);
    933 	eap_peer_tls_reset_input(data);
    934 	if (*in_decrypted == NULL) {
    935 		wpa_printf(MSG_INFO, "SSL: Failed to decrypt Phase 2 data");
    936 		return -1;
    937 	}
    938 	return 0;
    939 }
    940 
    941 
    942 /**
    943  * eap_peer_tls_encrypt - Encrypt phase 2 TLS message
    944  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    945  * @data: Data for TLS processing
    946  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    947  * @peap_version: Version number for EAP-PEAP/TTLS
    948  * @id: EAP identifier for the response
    949  * @in_data: Plaintext phase 2 data to encrypt or %NULL to continue fragments
    950  * @out_data: Buffer for returning a pointer to the encrypted response message
    951  * Returns: 0 on success, -1 on failure
    952  */
    953 int eap_peer_tls_encrypt(struct eap_sm *sm, struct eap_ssl_data *data,
    954 			 EapType eap_type, int peap_version, u8 id,
    955 			 const struct wpabuf *in_data,
    956 			 struct wpabuf **out_data)
    957 {
    958 	if (in_data) {
    959 		eap_peer_tls_reset_output(data);
    960 		data->tls_out = tls_connection_encrypt(data->ssl_ctx,
    961 						       data->conn, in_data);
    962 		if (data->tls_out == NULL) {
    963 			wpa_printf(MSG_INFO, "SSL: Failed to encrypt Phase 2 "
    964 				   "data (in_len=%lu)",
    965 				   (unsigned long) wpabuf_len(in_data));
    966 			eap_peer_tls_reset_output(data);
    967 			return -1;
    968 		}
    969 	}
    970 
    971 	return eap_tls_process_output(data, eap_type, peap_version, id, 0,
    972 				      out_data);
    973 }
    974 
    975 
    976 /**
    977  * eap_peer_select_phase2_methods - Select phase 2 EAP method
    978  * @config: Pointer to the network configuration
    979  * @prefix: 'phase2' configuration prefix, e.g., "auth="
    980  * @types: Buffer for returning allocated list of allowed EAP methods
    981  * @num_types: Buffer for returning number of allocated EAP methods
    982  * Returns: 0 on success, -1 on failure
    983  *
    984  * This function is used to parse EAP method list and select allowed methods
    985  * for Phase2 authentication.
    986  */
    987 int eap_peer_select_phase2_methods(struct eap_peer_config *config,
    988 				   const char *prefix,
    989 				   struct eap_method_type **types,
    990 				   size_t *num_types)
    991 {
    992 	char *start, *pos, *buf;
    993 	struct eap_method_type *methods = NULL, *_methods;
    994 	u32 method;
    995 	size_t num_methods = 0, prefix_len;
    996 
    997 	if (config == NULL || config->phase2 == NULL)
    998 		goto get_defaults;
    999 
   1000 	start = buf = os_strdup(config->phase2);
   1001 	if (buf == NULL)
   1002 		return -1;
   1003 
   1004 	prefix_len = os_strlen(prefix);
   1005 
   1006 	while (start && *start != '\0') {
   1007 		int vendor;
   1008 		pos = os_strstr(start, prefix);
   1009 		if (pos == NULL)
   1010 			break;
   1011 		if (start != pos && *(pos - 1) != ' ') {
   1012 			start = pos + prefix_len;
   1013 			continue;
   1014 		}
   1015 
   1016 		start = pos + prefix_len;
   1017 		pos = os_strchr(start, ' ');
   1018 		if (pos)
   1019 			*pos++ = '\0';
   1020 		method = eap_get_phase2_type(start, &vendor);
   1021 		if (vendor == EAP_VENDOR_IETF && method == EAP_TYPE_NONE) {
   1022 			wpa_printf(MSG_ERROR, "TLS: Unsupported Phase2 EAP "
   1023 				   "method '%s'", start);
   1024 		} else {
   1025 			num_methods++;
   1026 			_methods = os_realloc_array(methods, num_methods,
   1027 						    sizeof(*methods));
   1028 			if (_methods == NULL) {
   1029 				os_free(methods);
   1030 				os_free(buf);
   1031 				return -1;
   1032 			}
   1033 			methods = _methods;
   1034 			methods[num_methods - 1].vendor = vendor;
   1035 			methods[num_methods - 1].method = method;
   1036 		}
   1037 
   1038 		start = pos;
   1039 	}
   1040 
   1041 	os_free(buf);
   1042 
   1043 get_defaults:
   1044 	if (methods == NULL)
   1045 		methods = eap_get_phase2_types(config, &num_methods);
   1046 
   1047 	if (methods == NULL) {
   1048 		wpa_printf(MSG_ERROR, "TLS: No Phase2 EAP methods available");
   1049 		return -1;
   1050 	}
   1051 	wpa_hexdump(MSG_DEBUG, "TLS: Phase2 EAP types",
   1052 		    (u8 *) methods,
   1053 		    num_methods * sizeof(struct eap_method_type));
   1054 
   1055 	*types = methods;
   1056 	*num_types = num_methods;
   1057 
   1058 	return 0;
   1059 }
   1060 
   1061 
   1062 /**
   1063  * eap_peer_tls_phase2_nak - Generate EAP-Nak for Phase 2
   1064  * @types: Buffer for returning allocated list of allowed EAP methods
   1065  * @num_types: Buffer for returning number of allocated EAP methods
   1066  * @hdr: EAP-Request header (and the following EAP type octet)
   1067  * @resp: Buffer for returning the EAP-Nak message
   1068  * Returns: 0 on success, -1 on failure
   1069  */
   1070 int eap_peer_tls_phase2_nak(struct eap_method_type *types, size_t num_types,
   1071 			    struct eap_hdr *hdr, struct wpabuf **resp)
   1072 {
   1073 	u8 *pos = (u8 *) (hdr + 1);
   1074 	size_t i;
   1075 
   1076 	/* TODO: add support for expanded Nak */
   1077 	wpa_printf(MSG_DEBUG, "TLS: Phase 2 Request: Nak type=%d", *pos);
   1078 	wpa_hexdump(MSG_DEBUG, "TLS: Allowed Phase2 EAP types",
   1079 		    (u8 *) types, num_types * sizeof(struct eap_method_type));
   1080 	*resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_NAK, num_types,
   1081 			      EAP_CODE_RESPONSE, hdr->identifier);
   1082 	if (*resp == NULL)
   1083 		return -1;
   1084 
   1085 	for (i = 0; i < num_types; i++) {
   1086 		if (types[i].vendor == EAP_VENDOR_IETF &&
   1087 		    types[i].method < 256)
   1088 			wpabuf_put_u8(*resp, types[i].method);
   1089 	}
   1090 
   1091 	eap_update_len(*resp);
   1092 
   1093 	return 0;
   1094 }
   1095