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      1 /*
      2  * EAP peer: EAP-TLS/PEAP/TTLS/FAST common functions
      3  * Copyright (c) 2004-2019, 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_0=1"))
     72 		params->flags |= TLS_CONN_DISABLE_TLSv1_0;
     73 	if (os_strstr(txt, "tls_disable_tlsv1_0=0")) {
     74 		params->flags &= ~TLS_CONN_DISABLE_TLSv1_0;
     75 		params->flags |= TLS_CONN_ENABLE_TLSv1_0;
     76 	}
     77 	if (os_strstr(txt, "tls_disable_tlsv1_1=1"))
     78 		params->flags |= TLS_CONN_DISABLE_TLSv1_1;
     79 	if (os_strstr(txt, "tls_disable_tlsv1_1=0")) {
     80 		params->flags &= ~TLS_CONN_DISABLE_TLSv1_1;
     81 		params->flags |= TLS_CONN_ENABLE_TLSv1_1;
     82 	}
     83 	if (os_strstr(txt, "tls_disable_tlsv1_2=1"))
     84 		params->flags |= TLS_CONN_DISABLE_TLSv1_2;
     85 	if (os_strstr(txt, "tls_disable_tlsv1_2=0")) {
     86 		params->flags &= ~TLS_CONN_DISABLE_TLSv1_2;
     87 		params->flags |= TLS_CONN_ENABLE_TLSv1_2;
     88 	}
     89 	if (os_strstr(txt, "tls_disable_tlsv1_3=1"))
     90 		params->flags |= TLS_CONN_DISABLE_TLSv1_3;
     91 	if (os_strstr(txt, "tls_disable_tlsv1_3=0"))
     92 		params->flags &= ~TLS_CONN_DISABLE_TLSv1_3;
     93 	if (os_strstr(txt, "tls_ext_cert_check=1"))
     94 		params->flags |= TLS_CONN_EXT_CERT_CHECK;
     95 	if (os_strstr(txt, "tls_ext_cert_check=0"))
     96 		params->flags &= ~TLS_CONN_EXT_CERT_CHECK;
     97 	if (os_strstr(txt, "tls_suiteb=1"))
     98 		params->flags |= TLS_CONN_SUITEB;
     99 	if (os_strstr(txt, "tls_suiteb=0"))
    100 		params->flags &= ~TLS_CONN_SUITEB;
    101 	if (os_strstr(txt, "tls_suiteb_no_ecdh=1"))
    102 		params->flags |= TLS_CONN_SUITEB_NO_ECDH;
    103 	if (os_strstr(txt, "tls_suiteb_no_ecdh=0"))
    104 		params->flags &= ~TLS_CONN_SUITEB_NO_ECDH;
    105 }
    106 
    107 
    108 static void eap_tls_params_from_conf1(struct tls_connection_params *params,
    109 				      struct eap_peer_config *config)
    110 {
    111 	params->ca_cert = config->ca_cert;
    112 	params->ca_path = config->ca_path;
    113 	params->client_cert = config->client_cert;
    114 	params->private_key = config->private_key;
    115 	params->private_key_passwd = config->private_key_passwd;
    116 	params->dh_file = config->dh_file;
    117 	params->subject_match = config->subject_match;
    118 	params->altsubject_match = config->altsubject_match;
    119 	params->check_cert_subject = config->check_cert_subject;
    120 	params->suffix_match = config->domain_suffix_match;
    121 	params->domain_match = config->domain_match;
    122 	params->engine = config->engine;
    123 	params->engine_id = config->engine_id;
    124 	params->pin = config->pin;
    125 	params->key_id = config->key_id;
    126 	params->cert_id = config->cert_id;
    127 	params->ca_cert_id = config->ca_cert_id;
    128 	eap_tls_params_flags(params, config->phase1);
    129 }
    130 
    131 
    132 static void eap_tls_params_from_conf2(struct tls_connection_params *params,
    133 				      struct eap_peer_config *config)
    134 {
    135 	params->ca_cert = config->ca_cert2;
    136 	params->ca_path = config->ca_path2;
    137 	params->client_cert = config->client_cert2;
    138 	params->private_key = config->private_key2;
    139 	params->private_key_passwd = config->private_key2_passwd;
    140 	params->dh_file = config->dh_file2;
    141 	params->subject_match = config->subject_match2;
    142 	params->altsubject_match = config->altsubject_match2;
    143 	params->check_cert_subject = config->check_cert_subject2;
    144 	params->suffix_match = config->domain_suffix_match2;
    145 	params->domain_match = config->domain_match2;
    146 	params->engine = config->engine2;
    147 	params->engine_id = config->engine2_id;
    148 	params->pin = config->pin2;
    149 	params->key_id = config->key2_id;
    150 	params->cert_id = config->cert2_id;
    151 	params->ca_cert_id = config->ca_cert2_id;
    152 	eap_tls_params_flags(params, config->phase2);
    153 }
    154 
    155 
    156 static int eap_tls_params_from_conf(struct eap_sm *sm,
    157 				    struct eap_ssl_data *data,
    158 				    struct tls_connection_params *params,
    159 				    struct eap_peer_config *config, int phase2)
    160 {
    161 	os_memset(params, 0, sizeof(*params));
    162 	if (sm->workaround && data->eap_type != EAP_TYPE_FAST) {
    163 		/*
    164 		 * Some deployed authentication servers seem to be unable to
    165 		 * handle the TLS Session Ticket extension (they are supposed
    166 		 * to ignore unrecognized TLS extensions, but end up rejecting
    167 		 * the ClientHello instead). As a workaround, disable use of
    168 		 * TLS Sesson Ticket extension for EAP-TLS, EAP-PEAP, and
    169 		 * EAP-TTLS (EAP-FAST uses session ticket, so any server that
    170 		 * supports EAP-FAST does not need this workaround).
    171 		 */
    172 		params->flags |= TLS_CONN_DISABLE_SESSION_TICKET;
    173 	}
    174 	if (data->eap_type == EAP_TYPE_FAST ||
    175 	    data->eap_type == EAP_TYPE_TTLS ||
    176 	    data->eap_type == EAP_TYPE_PEAP) {
    177 		/* The current EAP peer implementation is not yet ready for the
    178 		 * TLS v1.3 changes, so disable this by default for now. */
    179 		params->flags |= TLS_CONN_DISABLE_TLSv1_3;
    180 	}
    181 	if (data->eap_type == EAP_TYPE_TLS ||
    182 	    data->eap_type == EAP_UNAUTH_TLS_TYPE ||
    183 	    data->eap_type == EAP_WFA_UNAUTH_TLS_TYPE) {
    184 		/* While the current EAP-TLS implementation is more or less
    185 		 * complete for TLS v1.3, there has been no interoperability
    186 		 * testing with other implementations, so disable for by default
    187 		 * for now until there has been chance to confirm that no
    188 		 * significant interoperability issues show up with TLS version
    189 		 * update.
    190 		 */
    191 		params->flags |= TLS_CONN_DISABLE_TLSv1_3;
    192 	}
    193 	if (phase2) {
    194 		wpa_printf(MSG_DEBUG, "TLS: using phase2 config options");
    195 		eap_tls_params_from_conf2(params, config);
    196 	} else {
    197 		wpa_printf(MSG_DEBUG, "TLS: using phase1 config options");
    198 		eap_tls_params_from_conf1(params, config);
    199 		if (data->eap_type == EAP_TYPE_FAST)
    200 			params->flags |= TLS_CONN_EAP_FAST;
    201 	}
    202 
    203 	/*
    204 	 * Use blob data, if available. Otherwise, leave reference to external
    205 	 * file as-is.
    206 	 */
    207 	if (eap_tls_check_blob(sm, &params->ca_cert, &params->ca_cert_blob,
    208 			       &params->ca_cert_blob_len) ||
    209 	    eap_tls_check_blob(sm, &params->client_cert,
    210 			       &params->client_cert_blob,
    211 			       &params->client_cert_blob_len) ||
    212 	    eap_tls_check_blob(sm, &params->private_key,
    213 			       &params->private_key_blob,
    214 			       &params->private_key_blob_len) ||
    215 	    eap_tls_check_blob(sm, &params->dh_file, &params->dh_blob,
    216 			       &params->dh_blob_len)) {
    217 		wpa_printf(MSG_INFO, "SSL: Failed to get configuration blobs");
    218 		return -1;
    219 	}
    220 
    221 	params->openssl_ciphers = config->openssl_ciphers;
    222 
    223 	sm->ext_cert_check = !!(params->flags & TLS_CONN_EXT_CERT_CHECK);
    224 
    225 	return 0;
    226 }
    227 
    228 
    229 static int eap_tls_init_connection(struct eap_sm *sm,
    230 				   struct eap_ssl_data *data,
    231 				   struct eap_peer_config *config,
    232 				   struct tls_connection_params *params)
    233 {
    234 	int res;
    235 
    236 	if (config->ocsp)
    237 		params->flags |= TLS_CONN_REQUEST_OCSP;
    238 	if (config->ocsp >= 2)
    239 		params->flags |= TLS_CONN_REQUIRE_OCSP;
    240 	if (config->ocsp == 3)
    241 		params->flags |= TLS_CONN_REQUIRE_OCSP_ALL;
    242 	data->conn = tls_connection_init(data->ssl_ctx);
    243 	if (data->conn == NULL) {
    244 		wpa_printf(MSG_INFO, "SSL: Failed to initialize new TLS "
    245 			   "connection");
    246 		return -1;
    247 	}
    248 
    249 	res = tls_connection_set_params(data->ssl_ctx, data->conn, params);
    250 	if (res == TLS_SET_PARAMS_ENGINE_PRV_BAD_PIN) {
    251 		/*
    252 		 * At this point with the pkcs11 engine the PIN is wrong. We
    253 		 * reset the PIN in the configuration to be sure to not use it
    254 		 * again and the calling function must request a new one.
    255 		 */
    256 		wpa_printf(MSG_INFO,
    257 			   "TLS: Bad PIN provided, requesting a new one");
    258 		os_free(config->pin);
    259 		config->pin = NULL;
    260 		eap_sm_request_pin(sm);
    261 		sm->ignore = TRUE;
    262 	} else if (res == TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED) {
    263 		wpa_printf(MSG_INFO, "TLS: Failed to initialize engine");
    264 	} else if (res == TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED) {
    265 		wpa_printf(MSG_INFO, "TLS: Failed to load private key");
    266 		sm->ignore = TRUE;
    267 	}
    268 	if (res) {
    269 		wpa_printf(MSG_INFO, "TLS: Failed to set TLS connection "
    270 			   "parameters");
    271 		tls_connection_deinit(data->ssl_ctx, data->conn);
    272 		data->conn = NULL;
    273 		return -1;
    274 	}
    275 
    276 	return 0;
    277 }
    278 
    279 
    280 /**
    281  * eap_peer_tls_ssl_init - Initialize shared TLS functionality
    282  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    283  * @data: Data for TLS processing
    284  * @config: Pointer to the network configuration
    285  * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
    286  * Returns: 0 on success, -1 on failure
    287  *
    288  * This function is used to initialize shared TLS functionality for EAP-TLS,
    289  * EAP-PEAP, EAP-TTLS, and EAP-FAST.
    290  */
    291 int eap_peer_tls_ssl_init(struct eap_sm *sm, struct eap_ssl_data *data,
    292 			  struct eap_peer_config *config, u8 eap_type)
    293 {
    294 	struct tls_connection_params params;
    295 
    296 	if (config == NULL)
    297 		return -1;
    298 
    299 	data->eap = sm;
    300 	data->eap_type = eap_type;
    301 	data->phase2 = sm->init_phase2;
    302 	data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
    303 		sm->ssl_ctx;
    304 	if (eap_tls_params_from_conf(sm, data, &params, config, data->phase2) <
    305 	    0)
    306 		return -1;
    307 
    308 	if (eap_tls_init_connection(sm, data, config, &params) < 0)
    309 		return -1;
    310 
    311 	data->tls_out_limit = config->fragment_size;
    312 	if (data->phase2) {
    313 		/* Limit the fragment size in the inner TLS authentication
    314 		 * since the outer authentication with EAP-PEAP does not yet
    315 		 * support fragmentation */
    316 		if (data->tls_out_limit > 100)
    317 			data->tls_out_limit -= 100;
    318 	}
    319 
    320 	if (config->phase1 &&
    321 	    os_strstr(config->phase1, "include_tls_length=1")) {
    322 		wpa_printf(MSG_DEBUG, "TLS: Include TLS Message Length in "
    323 			   "unfragmented packets");
    324 		data->include_tls_length = 1;
    325 	}
    326 
    327 	return 0;
    328 }
    329 
    330 
    331 /**
    332  * eap_peer_tls_ssl_deinit - Deinitialize shared TLS functionality
    333  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    334  * @data: Data for TLS processing
    335  *
    336  * This function deinitializes shared TLS functionality that was initialized
    337  * with eap_peer_tls_ssl_init().
    338  */
    339 void eap_peer_tls_ssl_deinit(struct eap_sm *sm, struct eap_ssl_data *data)
    340 {
    341 	tls_connection_deinit(data->ssl_ctx, data->conn);
    342 	eap_peer_tls_reset_input(data);
    343 	eap_peer_tls_reset_output(data);
    344 }
    345 
    346 
    347 /**
    348  * eap_peer_tls_derive_key - Derive a key based on TLS session data
    349  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    350  * @data: Data for TLS processing
    351  * @label: Label string for deriving the keys, e.g., "client EAP encryption"
    352  * @context: Optional extra upper-layer context (max len 2^16)
    353  * @context_len: The length of the context value
    354  * @len: Length of the key material to generate (usually 64 for MSK)
    355  * Returns: Pointer to allocated key on success or %NULL on failure
    356  *
    357  * This function uses TLS-PRF to generate pseudo-random data based on the TLS
    358  * session data (client/server random and master key). Each key type may use a
    359  * different label to bind the key usage into the generated material.
    360  *
    361  * The caller is responsible for freeing the returned buffer.
    362  *
    363  * Note: To provide the RFC 5705 context, the context variable must be non-NULL.
    364  */
    365 u8 * eap_peer_tls_derive_key(struct eap_sm *sm, struct eap_ssl_data *data,
    366 			     const char *label, const u8 *context,
    367 			     size_t context_len, size_t len)
    368 {
    369 	u8 *out;
    370 
    371 	out = os_malloc(len);
    372 	if (out == NULL)
    373 		return NULL;
    374 
    375 	if (tls_connection_export_key(data->ssl_ctx, data->conn, label,
    376 				      context, context_len, out, len)) {
    377 		os_free(out);
    378 		return NULL;
    379 	}
    380 
    381 	return out;
    382 }
    383 
    384 
    385 /**
    386  * eap_peer_tls_derive_session_id - Derive a Session-Id based on TLS data
    387  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    388  * @data: Data for TLS processing
    389  * @eap_type: EAP method used in Phase 1 (EAP_TYPE_TLS/PEAP/TTLS/FAST)
    390  * @len: Pointer to length of the session ID generated
    391  * Returns: Pointer to allocated Session-Id on success or %NULL on failure
    392  *
    393  * This function derive the Session-Id based on the TLS session data
    394  * (client/server random and method type).
    395  *
    396  * The caller is responsible for freeing the returned buffer.
    397  */
    398 u8 * eap_peer_tls_derive_session_id(struct eap_sm *sm,
    399 				    struct eap_ssl_data *data, u8 eap_type,
    400 				    size_t *len)
    401 {
    402 	struct tls_random keys;
    403 	u8 *out;
    404 
    405 	if (eap_type == EAP_TYPE_TLS && data->tls_v13) {
    406 		u8 *id, *method_id;
    407 
    408 		/* Session-Id = <EAP-Type> || Method-Id
    409 		 * Method-Id = TLS-Exporter("EXPORTER_EAP_TLS_Method-Id",
    410 		 *                          "", 64)
    411 		 */
    412 		*len = 1 + 64;
    413 		id = os_malloc(*len);
    414 		if (!id)
    415 			return NULL;
    416 		method_id = eap_peer_tls_derive_key(
    417 			sm, data, "EXPORTER_EAP_TLS_Method-Id", NULL, 0, 64);
    418 		if (!method_id) {
    419 			os_free(id);
    420 			return NULL;
    421 		}
    422 		id[0] = eap_type;
    423 		os_memcpy(id + 1, method_id, 64);
    424 		os_free(method_id);
    425 		return id;
    426 	}
    427 
    428 	if (tls_connection_get_random(sm->ssl_ctx, data->conn, &keys) ||
    429 	    keys.client_random == NULL || keys.server_random == NULL)
    430 		return NULL;
    431 
    432 	*len = 1 + keys.client_random_len + keys.server_random_len;
    433 	out = os_malloc(*len);
    434 	if (out == NULL)
    435 		return NULL;
    436 
    437 	/* Session-Id = EAP type || client.random || server.random */
    438 	out[0] = eap_type;
    439 	os_memcpy(out + 1, keys.client_random, keys.client_random_len);
    440 	os_memcpy(out + 1 + keys.client_random_len, keys.server_random,
    441 		  keys.server_random_len);
    442 
    443 	return out;
    444 }
    445 
    446 
    447 /**
    448  * eap_peer_tls_reassemble_fragment - Reassemble a received fragment
    449  * @data: Data for TLS processing
    450  * @in_data: Next incoming TLS segment
    451  * Returns: 0 on success, 1 if more data is needed for the full message, or
    452  * -1 on error
    453  */
    454 static int eap_peer_tls_reassemble_fragment(struct eap_ssl_data *data,
    455 					    const struct wpabuf *in_data)
    456 {
    457 	size_t tls_in_len, in_len;
    458 
    459 	tls_in_len = data->tls_in ? wpabuf_len(data->tls_in) : 0;
    460 	in_len = in_data ? wpabuf_len(in_data) : 0;
    461 
    462 	if (tls_in_len + in_len == 0) {
    463 		/* No message data received?! */
    464 		wpa_printf(MSG_WARNING, "SSL: Invalid reassembly state: "
    465 			   "tls_in_left=%lu tls_in_len=%lu in_len=%lu",
    466 			   (unsigned long) data->tls_in_left,
    467 			   (unsigned long) tls_in_len,
    468 			   (unsigned long) in_len);
    469 		eap_peer_tls_reset_input(data);
    470 		return -1;
    471 	}
    472 
    473 	if (tls_in_len + in_len > 65536) {
    474 		/*
    475 		 * Limit length to avoid rogue servers from causing large
    476 		 * memory allocations.
    477 		 */
    478 		wpa_printf(MSG_INFO, "SSL: Too long TLS fragment (size over "
    479 			   "64 kB)");
    480 		eap_peer_tls_reset_input(data);
    481 		return -1;
    482 	}
    483 
    484 	if (in_len > data->tls_in_left) {
    485 		/* Sender is doing something odd - reject message */
    486 		wpa_printf(MSG_INFO, "SSL: more data than TLS message length "
    487 			   "indicated");
    488 		eap_peer_tls_reset_input(data);
    489 		return -1;
    490 	}
    491 
    492 	if (wpabuf_resize(&data->tls_in, in_len) < 0) {
    493 		wpa_printf(MSG_INFO, "SSL: Could not allocate memory for TLS "
    494 			   "data");
    495 		eap_peer_tls_reset_input(data);
    496 		return -1;
    497 	}
    498 	if (in_data)
    499 		wpabuf_put_buf(data->tls_in, in_data);
    500 	data->tls_in_left -= in_len;
    501 
    502 	if (data->tls_in_left > 0) {
    503 		wpa_printf(MSG_DEBUG, "SSL: Need %lu bytes more input "
    504 			   "data", (unsigned long) data->tls_in_left);
    505 		return 1;
    506 	}
    507 
    508 	return 0;
    509 }
    510 
    511 
    512 /**
    513  * eap_peer_tls_data_reassemble - Reassemble TLS data
    514  * @data: Data for TLS processing
    515  * @in_data: Next incoming TLS segment
    516  * @need_more_input: Variable for returning whether more input data is needed
    517  * to reassemble this TLS packet
    518  * Returns: Pointer to output data, %NULL on error or when more data is needed
    519  * for the full message (in which case, *need_more_input is also set to 1).
    520  *
    521  * This function reassembles TLS fragments. Caller must not free the returned
    522  * data buffer since an internal pointer to it is maintained.
    523  */
    524 static const struct wpabuf * eap_peer_tls_data_reassemble(
    525 	struct eap_ssl_data *data, const struct wpabuf *in_data,
    526 	int *need_more_input)
    527 {
    528 	*need_more_input = 0;
    529 
    530 	if (data->tls_in_left > wpabuf_len(in_data) || data->tls_in) {
    531 		/* Message has fragments */
    532 		int res = eap_peer_tls_reassemble_fragment(data, in_data);
    533 		if (res) {
    534 			if (res == 1)
    535 				*need_more_input = 1;
    536 			return NULL;
    537 		}
    538 
    539 		/* Message is now fully reassembled. */
    540 	} else {
    541 		/* No fragments in this message, so just make a copy of it. */
    542 		data->tls_in_left = 0;
    543 		data->tls_in = wpabuf_dup(in_data);
    544 		if (data->tls_in == NULL)
    545 			return NULL;
    546 	}
    547 
    548 	return data->tls_in;
    549 }
    550 
    551 
    552 /**
    553  * eap_tls_process_input - Process incoming TLS message
    554  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    555  * @data: Data for TLS processing
    556  * @in_data: Message received from the server
    557  * @out_data: Buffer for returning a pointer to application data (if available)
    558  * Returns: 0 on success, 1 if more input data is needed, 2 if application data
    559  * is available, -1 on failure
    560  */
    561 static int eap_tls_process_input(struct eap_sm *sm, struct eap_ssl_data *data,
    562 				 const struct wpabuf *in_data,
    563 				 struct wpabuf **out_data)
    564 {
    565 	const struct wpabuf *msg;
    566 	int need_more_input;
    567 	struct wpabuf *appl_data;
    568 
    569 	msg = eap_peer_tls_data_reassemble(data, in_data, &need_more_input);
    570 	if (msg == NULL)
    571 		return need_more_input ? 1 : -1;
    572 
    573 	/* Full TLS message reassembled - continue handshake processing */
    574 	if (data->tls_out) {
    575 		/* This should not happen.. */
    576 		wpa_printf(MSG_INFO, "SSL: eap_tls_process_input - pending "
    577 			   "tls_out data even though tls_out_len = 0");
    578 		wpabuf_free(data->tls_out);
    579 		WPA_ASSERT(data->tls_out == NULL);
    580 	}
    581 	appl_data = NULL;
    582 	data->tls_out = tls_connection_handshake(data->ssl_ctx, data->conn,
    583 						 msg, &appl_data);
    584 
    585 	eap_peer_tls_reset_input(data);
    586 
    587 	if (appl_data &&
    588 	    tls_connection_established(data->ssl_ctx, data->conn) &&
    589 	    !tls_connection_get_failed(data->ssl_ctx, data->conn)) {
    590 		wpa_hexdump_buf_key(MSG_MSGDUMP, "SSL: Application data",
    591 				    appl_data);
    592 		*out_data = appl_data;
    593 		return 2;
    594 	}
    595 
    596 	wpabuf_free(appl_data);
    597 
    598 	return 0;
    599 }
    600 
    601 
    602 /**
    603  * eap_tls_process_output - Process outgoing TLS message
    604  * @data: Data for TLS processing
    605  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    606  * @peap_version: Version number for EAP-PEAP/TTLS
    607  * @id: EAP identifier for the response
    608  * @ret: Return value to use on success
    609  * @out_data: Buffer for returning the allocated output buffer
    610  * Returns: ret (0 or 1) on success, -1 on failure
    611  */
    612 static int eap_tls_process_output(struct eap_ssl_data *data, EapType eap_type,
    613 				  int peap_version, u8 id, int ret,
    614 				  struct wpabuf **out_data)
    615 {
    616 	size_t len;
    617 	u8 *flags;
    618 	int more_fragments, length_included;
    619 
    620 	if (data->tls_out == NULL)
    621 		return -1;
    622 	len = wpabuf_len(data->tls_out) - data->tls_out_pos;
    623 	wpa_printf(MSG_DEBUG, "SSL: %lu bytes left to be sent out (of total "
    624 		   "%lu bytes)",
    625 		   (unsigned long) len,
    626 		   (unsigned long) wpabuf_len(data->tls_out));
    627 
    628 	/*
    629 	 * Limit outgoing message to the configured maximum size. Fragment
    630 	 * message if needed.
    631 	 */
    632 	if (len > data->tls_out_limit) {
    633 		more_fragments = 1;
    634 		len = data->tls_out_limit;
    635 		wpa_printf(MSG_DEBUG, "SSL: sending %lu bytes, more fragments "
    636 			   "will follow", (unsigned long) len);
    637 	} else
    638 		more_fragments = 0;
    639 
    640 	length_included = data->tls_out_pos == 0 &&
    641 		(wpabuf_len(data->tls_out) > data->tls_out_limit ||
    642 		 data->include_tls_length);
    643 	if (!length_included &&
    644 	    eap_type == EAP_TYPE_PEAP && peap_version == 0 &&
    645 	    !tls_connection_established(data->eap->ssl_ctx, data->conn)) {
    646 		/*
    647 		 * Windows Server 2008 NPS really wants to have the TLS Message
    648 		 * length included in phase 0 even for unfragmented frames or
    649 		 * it will get very confused with Compound MAC calculation and
    650 		 * Outer TLVs.
    651 		 */
    652 		length_included = 1;
    653 	}
    654 
    655 	*out_data = eap_tls_msg_alloc(eap_type, 1 + length_included * 4 + len,
    656 				      EAP_CODE_RESPONSE, id);
    657 	if (*out_data == NULL)
    658 		return -1;
    659 
    660 	flags = wpabuf_put(*out_data, 1);
    661 	*flags = peap_version;
    662 	if (more_fragments)
    663 		*flags |= EAP_TLS_FLAGS_MORE_FRAGMENTS;
    664 	if (length_included) {
    665 		*flags |= EAP_TLS_FLAGS_LENGTH_INCLUDED;
    666 		wpabuf_put_be32(*out_data, wpabuf_len(data->tls_out));
    667 	}
    668 
    669 	wpabuf_put_data(*out_data,
    670 			wpabuf_head_u8(data->tls_out) + data->tls_out_pos,
    671 			len);
    672 	data->tls_out_pos += len;
    673 
    674 	if (!more_fragments)
    675 		eap_peer_tls_reset_output(data);
    676 
    677 	return ret;
    678 }
    679 
    680 
    681 /**
    682  * eap_peer_tls_process_helper - Process TLS handshake message
    683  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    684  * @data: Data for TLS processing
    685  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    686  * @peap_version: Version number for EAP-PEAP/TTLS
    687  * @id: EAP identifier for the response
    688  * @in_data: Message received from the server
    689  * @out_data: Buffer for returning a pointer to the response message
    690  * Returns: 0 on success, 1 if more input data is needed, 2 if application data
    691  * is available, or -1 on failure
    692  *
    693  * This function can be used to process TLS handshake messages. It reassembles
    694  * the received fragments and uses a TLS library to process the messages. The
    695  * response data from the TLS library is fragmented to suitable output messages
    696  * that the caller can send out.
    697  *
    698  * out_data is used to return the response message if the return value of this
    699  * function is 0, 2, or -1. In case of failure, the message is likely a TLS
    700  * alarm message. The caller is responsible for freeing the allocated buffer if
    701  * *out_data is not %NULL.
    702  *
    703  * This function is called for each received TLS message during the TLS
    704  * handshake after eap_peer_tls_process_init() call and possible processing of
    705  * TLS Flags field. Once the handshake has been completed, i.e., when
    706  * tls_connection_established() returns 1, EAP method specific decrypting of
    707  * the tunneled data is used.
    708  */
    709 int eap_peer_tls_process_helper(struct eap_sm *sm, struct eap_ssl_data *data,
    710 				EapType eap_type, int peap_version,
    711 				u8 id, const struct wpabuf *in_data,
    712 				struct wpabuf **out_data)
    713 {
    714 	int ret = 0;
    715 
    716 	*out_data = NULL;
    717 
    718 	if (data->tls_out && wpabuf_len(data->tls_out) > 0 &&
    719 	    wpabuf_len(in_data) > 0) {
    720 		wpa_printf(MSG_DEBUG, "SSL: Received non-ACK when output "
    721 			   "fragments are waiting to be sent out");
    722 		return -1;
    723 	}
    724 
    725 	if (data->tls_out == NULL || wpabuf_len(data->tls_out) == 0) {
    726 		/*
    727 		 * No more data to send out - expect to receive more data from
    728 		 * the AS.
    729 		 */
    730 		int res = eap_tls_process_input(sm, data, in_data, out_data);
    731 		char buf[20];
    732 
    733 		if (res) {
    734 			/*
    735 			 * Input processing failed (res = -1) or more data is
    736 			 * needed (res = 1).
    737 			 */
    738 			return res;
    739 		}
    740 
    741 		/*
    742 		 * The incoming message has been reassembled and processed. The
    743 		 * response was allocated into data->tls_out buffer.
    744 		 */
    745 
    746 		if (tls_get_version(data->ssl_ctx, data->conn,
    747 				    buf, sizeof(buf)) == 0) {
    748 			wpa_printf(MSG_DEBUG, "SSL: Using TLS version %s", buf);
    749 			data->tls_v13 = os_strcmp(buf, "TLSv1.3") == 0;
    750 		}
    751 	}
    752 
    753 	if (data->tls_out == NULL) {
    754 		/*
    755 		 * No outgoing fragments remaining from the previous message
    756 		 * and no new message generated. This indicates an error in TLS
    757 		 * processing.
    758 		 */
    759 		eap_peer_tls_reset_output(data);
    760 		return -1;
    761 	}
    762 
    763 	if (tls_connection_get_failed(data->ssl_ctx, data->conn)) {
    764 		/* TLS processing has failed - return error */
    765 		wpa_printf(MSG_DEBUG, "SSL: Failed - tls_out available to "
    766 			   "report error (len=%u)",
    767 			   (unsigned int) wpabuf_len(data->tls_out));
    768 		ret = -1;
    769 		/* TODO: clean pin if engine used? */
    770 		if (wpabuf_len(data->tls_out) == 0) {
    771 			wpabuf_free(data->tls_out);
    772 			data->tls_out = NULL;
    773 			return -1;
    774 		}
    775 	}
    776 
    777 	if (wpabuf_len(data->tls_out) == 0) {
    778 		/*
    779 		 * TLS negotiation should now be complete since all other cases
    780 		 * needing more data should have been caught above based on
    781 		 * the TLS Message Length field.
    782 		 */
    783 		wpa_printf(MSG_DEBUG, "SSL: No data to be sent out");
    784 		wpabuf_free(data->tls_out);
    785 		data->tls_out = NULL;
    786 		return 1;
    787 	}
    788 
    789 	/* Send the pending message (in fragments, if needed). */
    790 	return eap_tls_process_output(data, eap_type, peap_version, id, ret,
    791 				      out_data);
    792 }
    793 
    794 
    795 /**
    796  * eap_peer_tls_build_ack - Build a TLS ACK frame
    797  * @id: EAP identifier for the response
    798  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    799  * @peap_version: Version number for EAP-PEAP/TTLS
    800  * Returns: Pointer to the allocated ACK frame or %NULL on failure
    801  */
    802 struct wpabuf * eap_peer_tls_build_ack(u8 id, EapType eap_type,
    803 				       int peap_version)
    804 {
    805 	struct wpabuf *resp;
    806 
    807 	resp = eap_tls_msg_alloc(eap_type, 1, EAP_CODE_RESPONSE, id);
    808 	if (resp == NULL)
    809 		return NULL;
    810 	wpa_printf(MSG_DEBUG, "SSL: Building ACK (type=%d id=%d ver=%d)",
    811 		   (int) eap_type, id, peap_version);
    812 	wpabuf_put_u8(resp, peap_version); /* Flags */
    813 	return resp;
    814 }
    815 
    816 
    817 /**
    818  * eap_peer_tls_reauth_init - Re-initialize shared TLS for session resumption
    819  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    820  * @data: Data for TLS processing
    821  * Returns: 0 on success, -1 on failure
    822  */
    823 int eap_peer_tls_reauth_init(struct eap_sm *sm, struct eap_ssl_data *data)
    824 {
    825 	eap_peer_tls_reset_input(data);
    826 	eap_peer_tls_reset_output(data);
    827 	return tls_connection_shutdown(data->ssl_ctx, data->conn);
    828 }
    829 
    830 
    831 /**
    832  * eap_peer_tls_status - Get TLS status
    833  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    834  * @data: Data for TLS processing
    835  * @buf: Buffer for status information
    836  * @buflen: Maximum buffer length
    837  * @verbose: Whether to include verbose status information
    838  * Returns: Number of bytes written to buf.
    839  */
    840 int eap_peer_tls_status(struct eap_sm *sm, struct eap_ssl_data *data,
    841 			char *buf, size_t buflen, int verbose)
    842 {
    843 	char version[20], name[128];
    844 	int len = 0, ret;
    845 
    846 	if (tls_get_version(data->ssl_ctx, data->conn, version,
    847 			    sizeof(version)) < 0)
    848 		version[0] = '\0';
    849 	if (tls_get_cipher(data->ssl_ctx, data->conn, name, sizeof(name)) < 0)
    850 		name[0] = '\0';
    851 
    852 	ret = os_snprintf(buf + len, buflen - len,
    853 			  "eap_tls_version=%s\n"
    854 			  "EAP TLS cipher=%s\n"
    855 			  "tls_session_reused=%d\n",
    856 			  version, name,
    857 			  tls_connection_resumed(data->ssl_ctx, data->conn));
    858 	if (os_snprintf_error(buflen - len, ret))
    859 		return len;
    860 	len += ret;
    861 
    862 	return len;
    863 }
    864 
    865 
    866 /**
    867  * eap_peer_tls_process_init - Initial validation/processing of EAP requests
    868  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
    869  * @data: Data for TLS processing
    870  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
    871  * @ret: Return values from EAP request validation and processing
    872  * @reqData: EAP request to be processed (eapReqData)
    873  * @len: Buffer for returning length of the remaining payload
    874  * @flags: Buffer for returning TLS flags
    875  * Returns: Pointer to payload after TLS flags and length or %NULL on failure
    876  *
    877  * This function validates the EAP header and processes the optional TLS
    878  * Message Length field. If this is the first fragment of a TLS message, the
    879  * TLS reassembly code is initialized to receive the indicated number of bytes.
    880  *
    881  * EAP-TLS, EAP-PEAP, EAP-TTLS, and EAP-FAST methods are expected to use this
    882  * function as the first step in processing received messages. They will need
    883  * to process the flags (apart from Message Length Included) that are returned
    884  * through the flags pointer and the message payload that will be returned (and
    885  * the length is returned through the len pointer). Return values (ret) are set
    886  * for continuation of EAP method processing. The caller is responsible for
    887  * setting these to indicate completion (either success or failure) based on
    888  * the authentication result.
    889  */
    890 const u8 * eap_peer_tls_process_init(struct eap_sm *sm,
    891 				     struct eap_ssl_data *data,
    892 				     EapType eap_type,
    893 				     struct eap_method_ret *ret,
    894 				     const struct wpabuf *reqData,
    895 				     size_t *len, u8 *flags)
    896 {
    897 	const u8 *pos;
    898 	size_t left;
    899 	unsigned int tls_msg_len;
    900 
    901 	if (tls_get_errors(data->ssl_ctx)) {
    902 		wpa_printf(MSG_INFO, "SSL: TLS errors detected");
    903 		ret->ignore = TRUE;
    904 		return NULL;
    905 	}
    906 
    907 	if (eap_type == EAP_UNAUTH_TLS_TYPE)
    908 		pos = eap_hdr_validate(EAP_VENDOR_UNAUTH_TLS,
    909 				       EAP_VENDOR_TYPE_UNAUTH_TLS, reqData,
    910 				       &left);
    911 	else if (eap_type == EAP_WFA_UNAUTH_TLS_TYPE)
    912 		pos = eap_hdr_validate(EAP_VENDOR_WFA_NEW,
    913 				       EAP_VENDOR_WFA_UNAUTH_TLS, reqData,
    914 				       &left);
    915 	else
    916 		pos = eap_hdr_validate(EAP_VENDOR_IETF, eap_type, reqData,
    917 				       &left);
    918 	if (pos == NULL) {
    919 		ret->ignore = TRUE;
    920 		return NULL;
    921 	}
    922 	if (left == 0) {
    923 		wpa_printf(MSG_DEBUG, "SSL: Invalid TLS message: no Flags "
    924 			   "octet included");
    925 		if (!sm->workaround) {
    926 			ret->ignore = TRUE;
    927 			return NULL;
    928 		}
    929 
    930 		wpa_printf(MSG_DEBUG, "SSL: Workaround - assume no Flags "
    931 			   "indicates ACK frame");
    932 		*flags = 0;
    933 	} else {
    934 		*flags = *pos++;
    935 		left--;
    936 	}
    937 	wpa_printf(MSG_DEBUG, "SSL: Received packet(len=%lu) - "
    938 		   "Flags 0x%02x", (unsigned long) wpabuf_len(reqData),
    939 		   *flags);
    940 	if (*flags & EAP_TLS_FLAGS_LENGTH_INCLUDED) {
    941 		if (left < 4) {
    942 			wpa_printf(MSG_INFO, "SSL: Short frame with TLS "
    943 				   "length");
    944 			ret->ignore = TRUE;
    945 			return NULL;
    946 		}
    947 		tls_msg_len = WPA_GET_BE32(pos);
    948 		wpa_printf(MSG_DEBUG, "SSL: TLS Message Length: %d",
    949 			   tls_msg_len);
    950 		if (data->tls_in_left == 0) {
    951 			data->tls_in_total = tls_msg_len;
    952 			data->tls_in_left = tls_msg_len;
    953 			wpabuf_free(data->tls_in);
    954 			data->tls_in = NULL;
    955 		}
    956 		pos += 4;
    957 		left -= 4;
    958 
    959 		if (left > tls_msg_len) {
    960 			wpa_printf(MSG_INFO, "SSL: TLS Message Length (%d "
    961 				   "bytes) smaller than this fragment (%d "
    962 				   "bytes)", (int) tls_msg_len, (int) left);
    963 			ret->ignore = TRUE;
    964 			return NULL;
    965 		}
    966 	}
    967 
    968 	ret->ignore = FALSE;
    969 	ret->methodState = METHOD_MAY_CONT;
    970 	ret->decision = DECISION_FAIL;
    971 	ret->allowNotifications = TRUE;
    972 
    973 	*len = left;
    974 	return pos;
    975 }
    976 
    977 
    978 /**
    979  * eap_peer_tls_reset_input - Reset input buffers
    980  * @data: Data for TLS processing
    981  *
    982  * This function frees any allocated memory for input buffers and resets input
    983  * state.
    984  */
    985 void eap_peer_tls_reset_input(struct eap_ssl_data *data)
    986 {
    987 	data->tls_in_left = data->tls_in_total = 0;
    988 	wpabuf_free(data->tls_in);
    989 	data->tls_in = NULL;
    990 }
    991 
    992 
    993 /**
    994  * eap_peer_tls_reset_output - Reset output buffers
    995  * @data: Data for TLS processing
    996  *
    997  * This function frees any allocated memory for output buffers and resets
    998  * output state.
    999  */
   1000 void eap_peer_tls_reset_output(struct eap_ssl_data *data)
   1001 {
   1002 	data->tls_out_pos = 0;
   1003 	wpabuf_free(data->tls_out);
   1004 	data->tls_out = NULL;
   1005 }
   1006 
   1007 
   1008 /**
   1009  * eap_peer_tls_decrypt - Decrypt received phase 2 TLS message
   1010  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
   1011  * @data: Data for TLS processing
   1012  * @in_data: Message received from the server
   1013  * @in_decrypted: Buffer for returning a pointer to the decrypted message
   1014  * Returns: 0 on success, 1 if more input data is needed, or -1 on failure
   1015  */
   1016 int eap_peer_tls_decrypt(struct eap_sm *sm, struct eap_ssl_data *data,
   1017 			 const struct wpabuf *in_data,
   1018 			 struct wpabuf **in_decrypted)
   1019 {
   1020 	const struct wpabuf *msg;
   1021 	int need_more_input;
   1022 
   1023 	msg = eap_peer_tls_data_reassemble(data, in_data, &need_more_input);
   1024 	if (msg == NULL)
   1025 		return need_more_input ? 1 : -1;
   1026 
   1027 	*in_decrypted = tls_connection_decrypt(data->ssl_ctx, data->conn, msg);
   1028 	eap_peer_tls_reset_input(data);
   1029 	if (*in_decrypted == NULL) {
   1030 		wpa_printf(MSG_INFO, "SSL: Failed to decrypt Phase 2 data");
   1031 		return -1;
   1032 	}
   1033 	return 0;
   1034 }
   1035 
   1036 
   1037 /**
   1038  * eap_peer_tls_encrypt - Encrypt phase 2 TLS message
   1039  * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
   1040  * @data: Data for TLS processing
   1041  * @eap_type: EAP type (EAP_TYPE_TLS, EAP_TYPE_PEAP, ...)
   1042  * @peap_version: Version number for EAP-PEAP/TTLS
   1043  * @id: EAP identifier for the response
   1044  * @in_data: Plaintext phase 2 data to encrypt or %NULL to continue fragments
   1045  * @out_data: Buffer for returning a pointer to the encrypted response message
   1046  * Returns: 0 on success, -1 on failure
   1047  */
   1048 int eap_peer_tls_encrypt(struct eap_sm *sm, struct eap_ssl_data *data,
   1049 			 EapType eap_type, int peap_version, u8 id,
   1050 			 const struct wpabuf *in_data,
   1051 			 struct wpabuf **out_data)
   1052 {
   1053 	if (in_data) {
   1054 		eap_peer_tls_reset_output(data);
   1055 		data->tls_out = tls_connection_encrypt(data->ssl_ctx,
   1056 						       data->conn, in_data);
   1057 		if (data->tls_out == NULL) {
   1058 			wpa_printf(MSG_INFO, "SSL: Failed to encrypt Phase 2 "
   1059 				   "data (in_len=%lu)",
   1060 				   (unsigned long) wpabuf_len(in_data));
   1061 			eap_peer_tls_reset_output(data);
   1062 			return -1;
   1063 		}
   1064 	}
   1065 
   1066 	return eap_tls_process_output(data, eap_type, peap_version, id, 0,
   1067 				      out_data);
   1068 }
   1069 
   1070 
   1071 /**
   1072  * eap_peer_select_phase2_methods - Select phase 2 EAP method
   1073  * @config: Pointer to the network configuration
   1074  * @prefix: 'phase2' configuration prefix, e.g., "auth="
   1075  * @types: Buffer for returning allocated list of allowed EAP methods
   1076  * @num_types: Buffer for returning number of allocated EAP methods
   1077  * Returns: 0 on success, -1 on failure
   1078  *
   1079  * This function is used to parse EAP method list and select allowed methods
   1080  * for Phase2 authentication.
   1081  */
   1082 int eap_peer_select_phase2_methods(struct eap_peer_config *config,
   1083 				   const char *prefix,
   1084 				   struct eap_method_type **types,
   1085 				   size_t *num_types)
   1086 {
   1087 	char *start, *pos, *buf;
   1088 	struct eap_method_type *methods = NULL, *_methods;
   1089 	u32 method;
   1090 	size_t num_methods = 0, prefix_len;
   1091 
   1092 	if (config == NULL || config->phase2 == NULL)
   1093 		goto get_defaults;
   1094 
   1095 	start = buf = os_strdup(config->phase2);
   1096 	if (buf == NULL)
   1097 		return -1;
   1098 
   1099 	prefix_len = os_strlen(prefix);
   1100 
   1101 	while (start && *start != '\0') {
   1102 		int vendor;
   1103 		pos = os_strstr(start, prefix);
   1104 		if (pos == NULL)
   1105 			break;
   1106 		if (start != pos && *(pos - 1) != ' ') {
   1107 			start = pos + prefix_len;
   1108 			continue;
   1109 		}
   1110 
   1111 		start = pos + prefix_len;
   1112 		pos = os_strchr(start, ' ');
   1113 		if (pos)
   1114 			*pos++ = '\0';
   1115 		method = eap_get_phase2_type(start, &vendor);
   1116 		if (vendor == EAP_VENDOR_IETF && method == EAP_TYPE_NONE) {
   1117 			wpa_printf(MSG_ERROR, "TLS: Unsupported Phase2 EAP "
   1118 				   "method '%s'", start);
   1119 			os_free(methods);
   1120 			os_free(buf);
   1121 			return -1;
   1122 		} else {
   1123 			num_methods++;
   1124 			_methods = os_realloc_array(methods, num_methods,
   1125 						    sizeof(*methods));
   1126 			if (_methods == NULL) {
   1127 				os_free(methods);
   1128 				os_free(buf);
   1129 				return -1;
   1130 			}
   1131 			methods = _methods;
   1132 			methods[num_methods - 1].vendor = vendor;
   1133 			methods[num_methods - 1].method = method;
   1134 		}
   1135 
   1136 		start = pos;
   1137 	}
   1138 
   1139 	os_free(buf);
   1140 
   1141 get_defaults:
   1142 	if (methods == NULL)
   1143 		methods = eap_get_phase2_types(config, &num_methods);
   1144 
   1145 	if (methods == NULL) {
   1146 		wpa_printf(MSG_ERROR, "TLS: No Phase2 EAP methods available");
   1147 		return -1;
   1148 	}
   1149 	wpa_hexdump(MSG_DEBUG, "TLS: Phase2 EAP types",
   1150 		    (u8 *) methods,
   1151 		    num_methods * sizeof(struct eap_method_type));
   1152 
   1153 	*types = methods;
   1154 	*num_types = num_methods;
   1155 
   1156 	return 0;
   1157 }
   1158 
   1159 
   1160 /**
   1161  * eap_peer_tls_phase2_nak - Generate EAP-Nak for Phase 2
   1162  * @types: Buffer for returning allocated list of allowed EAP methods
   1163  * @num_types: Buffer for returning number of allocated EAP methods
   1164  * @hdr: EAP-Request header (and the following EAP type octet)
   1165  * @resp: Buffer for returning the EAP-Nak message
   1166  * Returns: 0 on success, -1 on failure
   1167  */
   1168 int eap_peer_tls_phase2_nak(struct eap_method_type *types, size_t num_types,
   1169 			    struct eap_hdr *hdr, struct wpabuf **resp)
   1170 {
   1171 	u8 *pos = (u8 *) (hdr + 1);
   1172 	size_t i;
   1173 
   1174 	/* TODO: add support for expanded Nak */
   1175 	wpa_printf(MSG_DEBUG, "TLS: Phase 2 Request: Nak type=%d", *pos);
   1176 	wpa_hexdump(MSG_DEBUG, "TLS: Allowed Phase2 EAP types",
   1177 		    (u8 *) types, num_types * sizeof(struct eap_method_type));
   1178 	*resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_NAK, num_types,
   1179 			      EAP_CODE_RESPONSE, hdr->identifier);
   1180 	if (*resp == NULL)
   1181 		return -1;
   1182 
   1183 	for (i = 0; i < num_types; i++) {
   1184 		if (types[i].vendor == EAP_VENDOR_IETF &&
   1185 		    types[i].method < 256)
   1186 			wpabuf_put_u8(*resp, types[i].method);
   1187 	}
   1188 
   1189 	eap_update_len(*resp);
   1190 
   1191 	return 0;
   1192 }
   1193