1 /* 2 * TLSv1 server (RFC 2246) 3 * Copyright (c) 2006-2007, Jouni Malinen <j (at) w1.fi> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * Alternatively, this software may be distributed under the terms of BSD 10 * license. 11 * 12 * See README and COPYING for more details. 13 */ 14 15 #include "includes.h" 16 17 #include "common.h" 18 #include "crypto/sha1.h" 19 #include "crypto/tls.h" 20 #include "tlsv1_common.h" 21 #include "tlsv1_record.h" 22 #include "tlsv1_server.h" 23 #include "tlsv1_server_i.h" 24 25 /* TODO: 26 * Support for a message fragmented across several records (RFC 2246, 6.2.1) 27 */ 28 29 30 void tlsv1_server_alert(struct tlsv1_server *conn, u8 level, u8 description) 31 { 32 conn->alert_level = level; 33 conn->alert_description = description; 34 } 35 36 37 int tlsv1_server_derive_keys(struct tlsv1_server *conn, 38 const u8 *pre_master_secret, 39 size_t pre_master_secret_len) 40 { 41 u8 seed[2 * TLS_RANDOM_LEN]; 42 u8 key_block[TLS_MAX_KEY_BLOCK_LEN]; 43 u8 *pos; 44 size_t key_block_len; 45 46 if (pre_master_secret) { 47 wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: pre_master_secret", 48 pre_master_secret, pre_master_secret_len); 49 os_memcpy(seed, conn->client_random, TLS_RANDOM_LEN); 50 os_memcpy(seed + TLS_RANDOM_LEN, conn->server_random, 51 TLS_RANDOM_LEN); 52 if (tls_prf(pre_master_secret, pre_master_secret_len, 53 "master secret", seed, 2 * TLS_RANDOM_LEN, 54 conn->master_secret, TLS_MASTER_SECRET_LEN)) { 55 wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive " 56 "master_secret"); 57 return -1; 58 } 59 wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: master_secret", 60 conn->master_secret, TLS_MASTER_SECRET_LEN); 61 } 62 63 os_memcpy(seed, conn->server_random, TLS_RANDOM_LEN); 64 os_memcpy(seed + TLS_RANDOM_LEN, conn->client_random, TLS_RANDOM_LEN); 65 key_block_len = 2 * (conn->rl.hash_size + conn->rl.key_material_len + 66 conn->rl.iv_size); 67 if (tls_prf(conn->master_secret, TLS_MASTER_SECRET_LEN, 68 "key expansion", seed, 2 * TLS_RANDOM_LEN, 69 key_block, key_block_len)) { 70 wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive key_block"); 71 return -1; 72 } 73 wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: key_block", 74 key_block, key_block_len); 75 76 pos = key_block; 77 78 /* client_write_MAC_secret */ 79 os_memcpy(conn->rl.read_mac_secret, pos, conn->rl.hash_size); 80 pos += conn->rl.hash_size; 81 /* server_write_MAC_secret */ 82 os_memcpy(conn->rl.write_mac_secret, pos, conn->rl.hash_size); 83 pos += conn->rl.hash_size; 84 85 /* client_write_key */ 86 os_memcpy(conn->rl.read_key, pos, conn->rl.key_material_len); 87 pos += conn->rl.key_material_len; 88 /* server_write_key */ 89 os_memcpy(conn->rl.write_key, pos, conn->rl.key_material_len); 90 pos += conn->rl.key_material_len; 91 92 /* client_write_IV */ 93 os_memcpy(conn->rl.read_iv, pos, conn->rl.iv_size); 94 pos += conn->rl.iv_size; 95 /* server_write_IV */ 96 os_memcpy(conn->rl.write_iv, pos, conn->rl.iv_size); 97 pos += conn->rl.iv_size; 98 99 return 0; 100 } 101 102 103 /** 104 * tlsv1_server_handshake - Process TLS handshake 105 * @conn: TLSv1 server connection data from tlsv1_server_init() 106 * @in_data: Input data from TLS peer 107 * @in_len: Input data length 108 * @out_len: Length of the output buffer. 109 * Returns: Pointer to output data, %NULL on failure 110 */ 111 u8 * tlsv1_server_handshake(struct tlsv1_server *conn, 112 const u8 *in_data, size_t in_len, 113 size_t *out_len) 114 { 115 const u8 *pos, *end; 116 u8 *msg = NULL, *in_msg, *in_pos, *in_end, alert, ct; 117 size_t in_msg_len; 118 119 if (in_data == NULL || in_len == 0) { 120 wpa_printf(MSG_DEBUG, "TLSv1: No input data to server"); 121 return NULL; 122 } 123 124 pos = in_data; 125 end = in_data + in_len; 126 in_msg = os_malloc(in_len); 127 if (in_msg == NULL) 128 return NULL; 129 130 /* Each received packet may include multiple records */ 131 while (pos < end) { 132 in_msg_len = in_len; 133 if (tlsv1_record_receive(&conn->rl, pos, end - pos, 134 in_msg, &in_msg_len, &alert)) { 135 wpa_printf(MSG_DEBUG, "TLSv1: Processing received " 136 "record failed"); 137 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, alert); 138 goto failed; 139 } 140 ct = pos[0]; 141 142 in_pos = in_msg; 143 in_end = in_msg + in_msg_len; 144 145 /* Each received record may include multiple messages of the 146 * same ContentType. */ 147 while (in_pos < in_end) { 148 in_msg_len = in_end - in_pos; 149 if (tlsv1_server_process_handshake(conn, ct, in_pos, 150 &in_msg_len) < 0) 151 goto failed; 152 in_pos += in_msg_len; 153 } 154 155 pos += TLS_RECORD_HEADER_LEN + WPA_GET_BE16(pos + 3); 156 } 157 158 os_free(in_msg); 159 in_msg = NULL; 160 161 msg = tlsv1_server_handshake_write(conn, out_len); 162 163 failed: 164 os_free(in_msg); 165 if (conn->alert_level) { 166 if (conn->state == FAILED) { 167 /* Avoid alert loops */ 168 wpa_printf(MSG_DEBUG, "TLSv1: Drop alert loop"); 169 os_free(msg); 170 return NULL; 171 } 172 conn->state = FAILED; 173 os_free(msg); 174 msg = tlsv1_server_send_alert(conn, conn->alert_level, 175 conn->alert_description, 176 out_len); 177 } 178 179 return msg; 180 } 181 182 183 /** 184 * tlsv1_server_encrypt - Encrypt data into TLS tunnel 185 * @conn: TLSv1 server connection data from tlsv1_server_init() 186 * @in_data: Pointer to plaintext data to be encrypted 187 * @in_len: Input buffer length 188 * @out_data: Pointer to output buffer (encrypted TLS data) 189 * @out_len: Maximum out_data length 190 * Returns: Number of bytes written to out_data, -1 on failure 191 * 192 * This function is used after TLS handshake has been completed successfully to 193 * send data in the encrypted tunnel. 194 */ 195 int tlsv1_server_encrypt(struct tlsv1_server *conn, 196 const u8 *in_data, size_t in_len, 197 u8 *out_data, size_t out_len) 198 { 199 size_t rlen; 200 201 wpa_hexdump_key(MSG_MSGDUMP, "TLSv1: Plaintext AppData", 202 in_data, in_len); 203 204 os_memcpy(out_data + TLS_RECORD_HEADER_LEN, in_data, in_len); 205 206 if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_APPLICATION_DATA, 207 out_data, out_len, in_len, &rlen) < 0) { 208 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record"); 209 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, 210 TLS_ALERT_INTERNAL_ERROR); 211 return -1; 212 } 213 214 return rlen; 215 } 216 217 218 /** 219 * tlsv1_server_decrypt - Decrypt data from TLS tunnel 220 * @conn: TLSv1 server connection data from tlsv1_server_init() 221 * @in_data: Pointer to input buffer (encrypted TLS data) 222 * @in_len: Input buffer length 223 * @out_data: Pointer to output buffer (decrypted data from TLS tunnel) 224 * @out_len: Maximum out_data length 225 * Returns: Number of bytes written to out_data, -1 on failure 226 * 227 * This function is used after TLS handshake has been completed successfully to 228 * receive data from the encrypted tunnel. 229 */ 230 int tlsv1_server_decrypt(struct tlsv1_server *conn, 231 const u8 *in_data, size_t in_len, 232 u8 *out_data, size_t out_len) 233 { 234 const u8 *in_end, *pos; 235 int res; 236 u8 alert, *out_end, *out_pos; 237 size_t olen; 238 239 pos = in_data; 240 in_end = in_data + in_len; 241 out_pos = out_data; 242 out_end = out_data + out_len; 243 244 while (pos < in_end) { 245 if (pos[0] != TLS_CONTENT_TYPE_APPLICATION_DATA) { 246 wpa_printf(MSG_DEBUG, "TLSv1: Unexpected content type " 247 "0x%x", pos[0]); 248 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, 249 TLS_ALERT_UNEXPECTED_MESSAGE); 250 return -1; 251 } 252 253 olen = out_end - out_pos; 254 res = tlsv1_record_receive(&conn->rl, pos, in_end - pos, 255 out_pos, &olen, &alert); 256 if (res < 0) { 257 wpa_printf(MSG_DEBUG, "TLSv1: Record layer processing " 258 "failed"); 259 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, alert); 260 return -1; 261 } 262 out_pos += olen; 263 if (out_pos > out_end) { 264 wpa_printf(MSG_DEBUG, "TLSv1: Buffer not large enough " 265 "for processing the received record"); 266 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, 267 TLS_ALERT_INTERNAL_ERROR); 268 return -1; 269 } 270 271 pos += TLS_RECORD_HEADER_LEN + WPA_GET_BE16(pos + 3); 272 } 273 274 return out_pos - out_data; 275 } 276 277 278 /** 279 * tlsv1_server_global_init - Initialize TLSv1 server 280 * Returns: 0 on success, -1 on failure 281 * 282 * This function must be called before using any other TLSv1 server functions. 283 */ 284 int tlsv1_server_global_init(void) 285 { 286 return crypto_global_init(); 287 } 288 289 290 /** 291 * tlsv1_server_global_deinit - Deinitialize TLSv1 server 292 * 293 * This function can be used to deinitialize the TLSv1 server that was 294 * initialized by calling tlsv1_server_global_init(). No TLSv1 server functions 295 * can be called after this before calling tlsv1_server_global_init() again. 296 */ 297 void tlsv1_server_global_deinit(void) 298 { 299 crypto_global_deinit(); 300 } 301 302 303 /** 304 * tlsv1_server_init - Initialize TLSv1 server connection 305 * @cred: Pointer to server credentials from tlsv1_server_cred_alloc() 306 * Returns: Pointer to TLSv1 server connection data or %NULL on failure 307 */ 308 struct tlsv1_server * tlsv1_server_init(struct tlsv1_credentials *cred) 309 { 310 struct tlsv1_server *conn; 311 size_t count; 312 u16 *suites; 313 314 conn = os_zalloc(sizeof(*conn)); 315 if (conn == NULL) 316 return NULL; 317 318 conn->cred = cred; 319 320 conn->state = CLIENT_HELLO; 321 322 if (tls_verify_hash_init(&conn->verify) < 0) { 323 wpa_printf(MSG_DEBUG, "TLSv1: Failed to initialize verify " 324 "hash"); 325 os_free(conn); 326 return NULL; 327 } 328 329 count = 0; 330 suites = conn->cipher_suites; 331 #ifndef CONFIG_CRYPTO_INTERNAL 332 suites[count++] = TLS_RSA_WITH_AES_256_CBC_SHA; 333 #endif /* CONFIG_CRYPTO_INTERNAL */ 334 suites[count++] = TLS_RSA_WITH_AES_128_CBC_SHA; 335 suites[count++] = TLS_RSA_WITH_3DES_EDE_CBC_SHA; 336 suites[count++] = TLS_RSA_WITH_RC4_128_SHA; 337 suites[count++] = TLS_RSA_WITH_RC4_128_MD5; 338 conn->num_cipher_suites = count; 339 340 return conn; 341 } 342 343 344 static void tlsv1_server_clear_data(struct tlsv1_server *conn) 345 { 346 tlsv1_record_set_cipher_suite(&conn->rl, TLS_NULL_WITH_NULL_NULL); 347 tlsv1_record_change_write_cipher(&conn->rl); 348 tlsv1_record_change_read_cipher(&conn->rl); 349 tls_verify_hash_free(&conn->verify); 350 351 crypto_public_key_free(conn->client_rsa_key); 352 conn->client_rsa_key = NULL; 353 354 os_free(conn->session_ticket); 355 conn->session_ticket = NULL; 356 conn->session_ticket_len = 0; 357 conn->use_session_ticket = 0; 358 359 os_free(conn->dh_secret); 360 conn->dh_secret = NULL; 361 conn->dh_secret_len = 0; 362 } 363 364 365 /** 366 * tlsv1_server_deinit - Deinitialize TLSv1 server connection 367 * @conn: TLSv1 server connection data from tlsv1_server_init() 368 */ 369 void tlsv1_server_deinit(struct tlsv1_server *conn) 370 { 371 tlsv1_server_clear_data(conn); 372 os_free(conn); 373 } 374 375 376 /** 377 * tlsv1_server_established - Check whether connection has been established 378 * @conn: TLSv1 server connection data from tlsv1_server_init() 379 * Returns: 1 if connection is established, 0 if not 380 */ 381 int tlsv1_server_established(struct tlsv1_server *conn) 382 { 383 return conn->state == ESTABLISHED; 384 } 385 386 387 /** 388 * tlsv1_server_prf - Use TLS-PRF to derive keying material 389 * @conn: TLSv1 server connection data from tlsv1_server_init() 390 * @label: Label (e.g., description of the key) for PRF 391 * @server_random_first: seed is 0 = client_random|server_random, 392 * 1 = server_random|client_random 393 * @out: Buffer for output data from TLS-PRF 394 * @out_len: Length of the output buffer 395 * Returns: 0 on success, -1 on failure 396 */ 397 int tlsv1_server_prf(struct tlsv1_server *conn, const char *label, 398 int server_random_first, u8 *out, size_t out_len) 399 { 400 u8 seed[2 * TLS_RANDOM_LEN]; 401 402 if (conn->state != ESTABLISHED) 403 return -1; 404 405 if (server_random_first) { 406 os_memcpy(seed, conn->server_random, TLS_RANDOM_LEN); 407 os_memcpy(seed + TLS_RANDOM_LEN, conn->client_random, 408 TLS_RANDOM_LEN); 409 } else { 410 os_memcpy(seed, conn->client_random, TLS_RANDOM_LEN); 411 os_memcpy(seed + TLS_RANDOM_LEN, conn->server_random, 412 TLS_RANDOM_LEN); 413 } 414 415 return tls_prf(conn->master_secret, TLS_MASTER_SECRET_LEN, 416 label, seed, 2 * TLS_RANDOM_LEN, out, out_len); 417 } 418 419 420 /** 421 * tlsv1_server_get_cipher - Get current cipher name 422 * @conn: TLSv1 server connection data from tlsv1_server_init() 423 * @buf: Buffer for the cipher name 424 * @buflen: buf size 425 * Returns: 0 on success, -1 on failure 426 * 427 * Get the name of the currently used cipher. 428 */ 429 int tlsv1_server_get_cipher(struct tlsv1_server *conn, char *buf, 430 size_t buflen) 431 { 432 char *cipher; 433 434 switch (conn->rl.cipher_suite) { 435 case TLS_RSA_WITH_RC4_128_MD5: 436 cipher = "RC4-MD5"; 437 break; 438 case TLS_RSA_WITH_RC4_128_SHA: 439 cipher = "RC4-SHA"; 440 break; 441 case TLS_RSA_WITH_DES_CBC_SHA: 442 cipher = "DES-CBC-SHA"; 443 break; 444 case TLS_RSA_WITH_3DES_EDE_CBC_SHA: 445 cipher = "DES-CBC3-SHA"; 446 break; 447 case TLS_DH_anon_WITH_AES_128_CBC_SHA: 448 cipher = "ADH-AES-128-SHA"; 449 break; 450 case TLS_RSA_WITH_AES_256_CBC_SHA: 451 cipher = "AES-256-SHA"; 452 break; 453 case TLS_RSA_WITH_AES_128_CBC_SHA: 454 cipher = "AES-128-SHA"; 455 break; 456 default: 457 return -1; 458 } 459 460 if (os_strlcpy(buf, cipher, buflen) >= buflen) 461 return -1; 462 return 0; 463 } 464 465 466 /** 467 * tlsv1_server_shutdown - Shutdown TLS connection 468 * @conn: TLSv1 server connection data from tlsv1_server_init() 469 * Returns: 0 on success, -1 on failure 470 */ 471 int tlsv1_server_shutdown(struct tlsv1_server *conn) 472 { 473 conn->state = CLIENT_HELLO; 474 475 if (tls_verify_hash_init(&conn->verify) < 0) { 476 wpa_printf(MSG_DEBUG, "TLSv1: Failed to re-initialize verify " 477 "hash"); 478 return -1; 479 } 480 481 tlsv1_server_clear_data(conn); 482 483 return 0; 484 } 485 486 487 /** 488 * tlsv1_server_resumed - Was session resumption used 489 * @conn: TLSv1 server connection data from tlsv1_server_init() 490 * Returns: 1 if current session used session resumption, 0 if not 491 */ 492 int tlsv1_server_resumed(struct tlsv1_server *conn) 493 { 494 return 0; 495 } 496 497 498 /** 499 * tlsv1_server_get_keys - Get master key and random data from TLS connection 500 * @conn: TLSv1 server connection data from tlsv1_server_init() 501 * @keys: Structure of key/random data (filled on success) 502 * Returns: 0 on success, -1 on failure 503 */ 504 int tlsv1_server_get_keys(struct tlsv1_server *conn, struct tls_keys *keys) 505 { 506 os_memset(keys, 0, sizeof(*keys)); 507 if (conn->state == CLIENT_HELLO) 508 return -1; 509 510 keys->client_random = conn->client_random; 511 keys->client_random_len = TLS_RANDOM_LEN; 512 513 if (conn->state != SERVER_HELLO) { 514 keys->server_random = conn->server_random; 515 keys->server_random_len = TLS_RANDOM_LEN; 516 keys->master_key = conn->master_secret; 517 keys->master_key_len = TLS_MASTER_SECRET_LEN; 518 } 519 520 return 0; 521 } 522 523 524 /** 525 * tlsv1_server_get_keyblock_size - Get TLS key_block size 526 * @conn: TLSv1 server connection data from tlsv1_server_init() 527 * Returns: Size of the key_block for the negotiated cipher suite or -1 on 528 * failure 529 */ 530 int tlsv1_server_get_keyblock_size(struct tlsv1_server *conn) 531 { 532 if (conn->state == CLIENT_HELLO || conn->state == SERVER_HELLO) 533 return -1; 534 535 return 2 * (conn->rl.hash_size + conn->rl.key_material_len + 536 conn->rl.iv_size); 537 } 538 539 540 /** 541 * tlsv1_server_set_cipher_list - Configure acceptable cipher suites 542 * @conn: TLSv1 server connection data from tlsv1_server_init() 543 * @ciphers: Zero (TLS_CIPHER_NONE) terminated list of allowed ciphers 544 * (TLS_CIPHER_*). 545 * Returns: 0 on success, -1 on failure 546 */ 547 int tlsv1_server_set_cipher_list(struct tlsv1_server *conn, u8 *ciphers) 548 { 549 size_t count; 550 u16 *suites; 551 552 /* TODO: implement proper configuration of cipher suites */ 553 if (ciphers[0] == TLS_CIPHER_ANON_DH_AES128_SHA) { 554 count = 0; 555 suites = conn->cipher_suites; 556 #ifndef CONFIG_CRYPTO_INTERNAL 557 suites[count++] = TLS_RSA_WITH_AES_256_CBC_SHA; 558 #endif /* CONFIG_CRYPTO_INTERNAL */ 559 suites[count++] = TLS_RSA_WITH_AES_128_CBC_SHA; 560 suites[count++] = TLS_RSA_WITH_3DES_EDE_CBC_SHA; 561 suites[count++] = TLS_RSA_WITH_RC4_128_SHA; 562 suites[count++] = TLS_RSA_WITH_RC4_128_MD5; 563 #ifndef CONFIG_CRYPTO_INTERNAL 564 suites[count++] = TLS_DH_anon_WITH_AES_256_CBC_SHA; 565 #endif /* CONFIG_CRYPTO_INTERNAL */ 566 suites[count++] = TLS_DH_anon_WITH_AES_128_CBC_SHA; 567 suites[count++] = TLS_DH_anon_WITH_3DES_EDE_CBC_SHA; 568 suites[count++] = TLS_DH_anon_WITH_RC4_128_MD5; 569 suites[count++] = TLS_DH_anon_WITH_DES_CBC_SHA; 570 conn->num_cipher_suites = count; 571 } 572 573 return 0; 574 } 575 576 577 int tlsv1_server_set_verify(struct tlsv1_server *conn, int verify_peer) 578 { 579 conn->verify_peer = verify_peer; 580 return 0; 581 } 582 583 584 void tlsv1_server_set_session_ticket_cb(struct tlsv1_server *conn, 585 tlsv1_server_session_ticket_cb cb, 586 void *ctx) 587 { 588 wpa_printf(MSG_DEBUG, "TLSv1: SessionTicket callback set %p (ctx %p)", 589 cb, ctx); 590 conn->session_ticket_cb = cb; 591 conn->session_ticket_cb_ctx = ctx; 592 } 593
