1 /* 2 * hostapd / IEEE 802.11 authentication (ACL) 3 * Copyright (c) 2003-2012, Jouni Malinen <j@w1.fi> 4 * 5 * This software may be distributed under the terms of the BSD license. 6 * See README for more details. 7 * 8 * Access control list for IEEE 802.11 authentication can uses statically 9 * configured ACL from configuration files or an external RADIUS server. 10 * Results from external RADIUS queries are cached to allow faster 11 * authentication frame processing. 12 */ 13 14 #include "utils/includes.h" 15 16 #include "utils/common.h" 17 #include "utils/eloop.h" 18 #include "crypto/sha1.h" 19 #include "radius/radius.h" 20 #include "radius/radius_client.h" 21 #include "hostapd.h" 22 #include "ap_config.h" 23 #include "ap_drv_ops.h" 24 #include "ieee802_11.h" 25 #include "ieee802_1x.h" 26 #include "ieee802_11_auth.h" 27 28 #define RADIUS_ACL_TIMEOUT 30 29 30 31 struct hostapd_cached_radius_acl { 32 struct os_reltime timestamp; 33 macaddr addr; 34 int accepted; /* HOSTAPD_ACL_* */ 35 struct hostapd_cached_radius_acl *next; 36 u32 session_timeout; 37 u32 acct_interim_interval; 38 int vlan_id; 39 struct hostapd_sta_wpa_psk_short *psk; 40 char *identity; 41 char *radius_cui; 42 }; 43 44 45 struct hostapd_acl_query_data { 46 struct os_reltime timestamp; 47 u8 radius_id; 48 macaddr addr; 49 u8 *auth_msg; /* IEEE 802.11 authentication frame from station */ 50 size_t auth_msg_len; 51 struct hostapd_acl_query_data *next; 52 }; 53 54 55 #ifndef CONFIG_NO_RADIUS 56 static void hostapd_acl_cache_free_entry(struct hostapd_cached_radius_acl *e) 57 { 58 os_free(e->identity); 59 os_free(e->radius_cui); 60 hostapd_free_psk_list(e->psk); 61 os_free(e); 62 } 63 64 65 static void hostapd_acl_cache_free(struct hostapd_cached_radius_acl *acl_cache) 66 { 67 struct hostapd_cached_radius_acl *prev; 68 69 while (acl_cache) { 70 prev = acl_cache; 71 acl_cache = acl_cache->next; 72 hostapd_acl_cache_free_entry(prev); 73 } 74 } 75 76 77 static void copy_psk_list(struct hostapd_sta_wpa_psk_short **psk, 78 struct hostapd_sta_wpa_psk_short *src) 79 { 80 struct hostapd_sta_wpa_psk_short **copy_to; 81 struct hostapd_sta_wpa_psk_short *copy_from; 82 83 /* Copy PSK linked list */ 84 copy_to = psk; 85 copy_from = src; 86 while (copy_from && copy_to) { 87 *copy_to = os_zalloc(sizeof(struct hostapd_sta_wpa_psk_short)); 88 if (*copy_to == NULL) 89 break; 90 os_memcpy(*copy_to, copy_from, 91 sizeof(struct hostapd_sta_wpa_psk_short)); 92 copy_from = copy_from->next; 93 copy_to = &((*copy_to)->next); 94 } 95 if (copy_to) 96 *copy_to = NULL; 97 } 98 99 100 static int hostapd_acl_cache_get(struct hostapd_data *hapd, const u8 *addr, 101 u32 *session_timeout, 102 u32 *acct_interim_interval, int *vlan_id, 103 struct hostapd_sta_wpa_psk_short **psk, 104 char **identity, char **radius_cui) 105 { 106 struct hostapd_cached_radius_acl *entry; 107 struct os_reltime now; 108 109 os_get_reltime(&now); 110 111 for (entry = hapd->acl_cache; entry; entry = entry->next) { 112 if (os_memcmp(entry->addr, addr, ETH_ALEN) != 0) 113 continue; 114 115 if (os_reltime_expired(&now, &entry->timestamp, 116 RADIUS_ACL_TIMEOUT)) 117 return -1; /* entry has expired */ 118 if (entry->accepted == HOSTAPD_ACL_ACCEPT_TIMEOUT) 119 if (session_timeout) 120 *session_timeout = entry->session_timeout; 121 if (acct_interim_interval) 122 *acct_interim_interval = 123 entry->acct_interim_interval; 124 if (vlan_id) 125 *vlan_id = entry->vlan_id; 126 copy_psk_list(psk, entry->psk); 127 if (identity) { 128 if (entry->identity) 129 *identity = os_strdup(entry->identity); 130 else 131 *identity = NULL; 132 } 133 if (radius_cui) { 134 if (entry->radius_cui) 135 *radius_cui = os_strdup(entry->radius_cui); 136 else 137 *radius_cui = NULL; 138 } 139 return entry->accepted; 140 } 141 142 return -1; 143 } 144 #endif /* CONFIG_NO_RADIUS */ 145 146 147 static void hostapd_acl_query_free(struct hostapd_acl_query_data *query) 148 { 149 if (query == NULL) 150 return; 151 os_free(query->auth_msg); 152 os_free(query); 153 } 154 155 156 #ifndef CONFIG_NO_RADIUS 157 static int hostapd_radius_acl_query(struct hostapd_data *hapd, const u8 *addr, 158 struct hostapd_acl_query_data *query) 159 { 160 struct radius_msg *msg; 161 char buf[128]; 162 163 query->radius_id = radius_client_get_id(hapd->radius); 164 msg = radius_msg_new(RADIUS_CODE_ACCESS_REQUEST, query->radius_id); 165 if (msg == NULL) 166 return -1; 167 168 radius_msg_make_authenticator(msg, addr, ETH_ALEN); 169 170 os_snprintf(buf, sizeof(buf), RADIUS_ADDR_FORMAT, MAC2STR(addr)); 171 if (!radius_msg_add_attr(msg, RADIUS_ATTR_USER_NAME, (u8 *) buf, 172 os_strlen(buf))) { 173 wpa_printf(MSG_DEBUG, "Could not add User-Name"); 174 goto fail; 175 } 176 177 if (!radius_msg_add_attr_user_password( 178 msg, (u8 *) buf, os_strlen(buf), 179 hapd->conf->radius->auth_server->shared_secret, 180 hapd->conf->radius->auth_server->shared_secret_len)) { 181 wpa_printf(MSG_DEBUG, "Could not add User-Password"); 182 goto fail; 183 } 184 185 if (add_common_radius_attr(hapd, hapd->conf->radius_auth_req_attr, 186 NULL, msg) < 0) 187 goto fail; 188 189 os_snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT, 190 MAC2STR(addr)); 191 if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLING_STATION_ID, 192 (u8 *) buf, os_strlen(buf))) { 193 wpa_printf(MSG_DEBUG, "Could not add Calling-Station-Id"); 194 goto fail; 195 } 196 197 os_snprintf(buf, sizeof(buf), "CONNECT 11Mbps 802.11b"); 198 if (!radius_msg_add_attr(msg, RADIUS_ATTR_CONNECT_INFO, 199 (u8 *) buf, os_strlen(buf))) { 200 wpa_printf(MSG_DEBUG, "Could not add Connect-Info"); 201 goto fail; 202 } 203 204 if (radius_client_send(hapd->radius, msg, RADIUS_AUTH, addr) < 0) 205 goto fail; 206 return 0; 207 208 fail: 209 radius_msg_free(msg); 210 return -1; 211 } 212 #endif /* CONFIG_NO_RADIUS */ 213 214 215 /** 216 * hostapd_allowed_address - Check whether a specified STA can be authenticated 217 * @hapd: hostapd BSS data 218 * @addr: MAC address of the STA 219 * @msg: Authentication message 220 * @len: Length of msg in octets 221 * @session_timeout: Buffer for returning session timeout (from RADIUS) 222 * @acct_interim_interval: Buffer for returning account interval (from RADIUS) 223 * @vlan_id: Buffer for returning VLAN ID 224 * @psk: Linked list buffer for returning WPA PSK 225 * @identity: Buffer for returning identity (from RADIUS) 226 * @radius_cui: Buffer for returning CUI (from RADIUS) 227 * Returns: HOSTAPD_ACL_ACCEPT, HOSTAPD_ACL_REJECT, or HOSTAPD_ACL_PENDING 228 * 229 * The caller is responsible for freeing the returned *identity and *radius_cui 230 * values with os_free(). 231 */ 232 int hostapd_allowed_address(struct hostapd_data *hapd, const u8 *addr, 233 const u8 *msg, size_t len, u32 *session_timeout, 234 u32 *acct_interim_interval, int *vlan_id, 235 struct hostapd_sta_wpa_psk_short **psk, 236 char **identity, char **radius_cui) 237 { 238 if (session_timeout) 239 *session_timeout = 0; 240 if (acct_interim_interval) 241 *acct_interim_interval = 0; 242 if (vlan_id) 243 *vlan_id = 0; 244 if (psk) 245 *psk = NULL; 246 if (identity) 247 *identity = NULL; 248 if (radius_cui) 249 *radius_cui = NULL; 250 251 if (hostapd_maclist_found(hapd->conf->accept_mac, 252 hapd->conf->num_accept_mac, addr, vlan_id)) 253 return HOSTAPD_ACL_ACCEPT; 254 255 if (hostapd_maclist_found(hapd->conf->deny_mac, 256 hapd->conf->num_deny_mac, addr, vlan_id)) 257 return HOSTAPD_ACL_REJECT; 258 259 if (hapd->conf->macaddr_acl == ACCEPT_UNLESS_DENIED) 260 return HOSTAPD_ACL_ACCEPT; 261 if (hapd->conf->macaddr_acl == DENY_UNLESS_ACCEPTED) 262 return HOSTAPD_ACL_REJECT; 263 264 if (hapd->conf->macaddr_acl == USE_EXTERNAL_RADIUS_AUTH) { 265 #ifdef CONFIG_NO_RADIUS 266 return HOSTAPD_ACL_REJECT; 267 #else /* CONFIG_NO_RADIUS */ 268 struct hostapd_acl_query_data *query; 269 270 /* Check whether ACL cache has an entry for this station */ 271 int res = hostapd_acl_cache_get(hapd, addr, session_timeout, 272 acct_interim_interval, 273 vlan_id, psk, 274 identity, radius_cui); 275 if (res == HOSTAPD_ACL_ACCEPT || 276 res == HOSTAPD_ACL_ACCEPT_TIMEOUT) 277 return res; 278 if (res == HOSTAPD_ACL_REJECT) 279 return HOSTAPD_ACL_REJECT; 280 281 query = hapd->acl_queries; 282 while (query) { 283 if (os_memcmp(query->addr, addr, ETH_ALEN) == 0) { 284 /* pending query in RADIUS retransmit queue; 285 * do not generate a new one */ 286 if (identity) { 287 os_free(*identity); 288 *identity = NULL; 289 } 290 if (radius_cui) { 291 os_free(*radius_cui); 292 *radius_cui = NULL; 293 } 294 return HOSTAPD_ACL_PENDING; 295 } 296 query = query->next; 297 } 298 299 if (!hapd->conf->radius->auth_server) 300 return HOSTAPD_ACL_REJECT; 301 302 /* No entry in the cache - query external RADIUS server */ 303 query = os_zalloc(sizeof(*query)); 304 if (query == NULL) { 305 wpa_printf(MSG_ERROR, "malloc for query data failed"); 306 return HOSTAPD_ACL_REJECT; 307 } 308 os_get_reltime(&query->timestamp); 309 os_memcpy(query->addr, addr, ETH_ALEN); 310 if (hostapd_radius_acl_query(hapd, addr, query)) { 311 wpa_printf(MSG_DEBUG, "Failed to send Access-Request " 312 "for ACL query."); 313 hostapd_acl_query_free(query); 314 return HOSTAPD_ACL_REJECT; 315 } 316 317 query->auth_msg = os_malloc(len); 318 if (query->auth_msg == NULL) { 319 wpa_printf(MSG_ERROR, "Failed to allocate memory for " 320 "auth frame."); 321 hostapd_acl_query_free(query); 322 return HOSTAPD_ACL_REJECT; 323 } 324 os_memcpy(query->auth_msg, msg, len); 325 query->auth_msg_len = len; 326 query->next = hapd->acl_queries; 327 hapd->acl_queries = query; 328 329 /* Queued data will be processed in hostapd_acl_recv_radius() 330 * when RADIUS server replies to the sent Access-Request. */ 331 return HOSTAPD_ACL_PENDING; 332 #endif /* CONFIG_NO_RADIUS */ 333 } 334 335 return HOSTAPD_ACL_REJECT; 336 } 337 338 339 #ifndef CONFIG_NO_RADIUS 340 static void hostapd_acl_expire_cache(struct hostapd_data *hapd, 341 struct os_reltime *now) 342 { 343 struct hostapd_cached_radius_acl *prev, *entry, *tmp; 344 345 prev = NULL; 346 entry = hapd->acl_cache; 347 348 while (entry) { 349 if (os_reltime_expired(now, &entry->timestamp, 350 RADIUS_ACL_TIMEOUT)) { 351 wpa_printf(MSG_DEBUG, "Cached ACL entry for " MACSTR 352 " has expired.", MAC2STR(entry->addr)); 353 if (prev) 354 prev->next = entry->next; 355 else 356 hapd->acl_cache = entry->next; 357 hostapd_drv_set_radius_acl_expire(hapd, entry->addr); 358 tmp = entry; 359 entry = entry->next; 360 hostapd_acl_cache_free_entry(tmp); 361 continue; 362 } 363 364 prev = entry; 365 entry = entry->next; 366 } 367 } 368 369 370 static void hostapd_acl_expire_queries(struct hostapd_data *hapd, 371 struct os_reltime *now) 372 { 373 struct hostapd_acl_query_data *prev, *entry, *tmp; 374 375 prev = NULL; 376 entry = hapd->acl_queries; 377 378 while (entry) { 379 if (os_reltime_expired(now, &entry->timestamp, 380 RADIUS_ACL_TIMEOUT)) { 381 wpa_printf(MSG_DEBUG, "ACL query for " MACSTR 382 " has expired.", MAC2STR(entry->addr)); 383 if (prev) 384 prev->next = entry->next; 385 else 386 hapd->acl_queries = entry->next; 387 388 tmp = entry; 389 entry = entry->next; 390 hostapd_acl_query_free(tmp); 391 continue; 392 } 393 394 prev = entry; 395 entry = entry->next; 396 } 397 } 398 399 400 /** 401 * hostapd_acl_expire - ACL cache expiration callback 402 * @eloop_ctx: struct hostapd_data * 403 * @timeout_ctx: Not used 404 */ 405 static void hostapd_acl_expire(void *eloop_ctx, void *timeout_ctx) 406 { 407 struct hostapd_data *hapd = eloop_ctx; 408 struct os_reltime now; 409 410 os_get_reltime(&now); 411 hostapd_acl_expire_cache(hapd, &now); 412 hostapd_acl_expire_queries(hapd, &now); 413 414 eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL); 415 } 416 417 418 static void decode_tunnel_passwords(struct hostapd_data *hapd, 419 const u8 *shared_secret, 420 size_t shared_secret_len, 421 struct radius_msg *msg, 422 struct radius_msg *req, 423 struct hostapd_cached_radius_acl *cache) 424 { 425 int passphraselen; 426 char *passphrase, *strpassphrase; 427 size_t i; 428 struct hostapd_sta_wpa_psk_short *psk; 429 430 /* 431 * Decode all tunnel passwords as PSK and save them into a linked list. 432 */ 433 for (i = 0; ; i++) { 434 passphrase = radius_msg_get_tunnel_password( 435 msg, &passphraselen, shared_secret, shared_secret_len, 436 req, i); 437 /* 438 * Passphrase is NULL iff there is no i-th Tunnel-Password 439 * attribute in msg. 440 */ 441 if (passphrase == NULL) 442 break; 443 /* 444 * passphrase does not contain the NULL termination. 445 * Add it here as pbkdf2_sha1() requires it. 446 */ 447 strpassphrase = os_zalloc(passphraselen + 1); 448 psk = os_zalloc(sizeof(struct hostapd_sta_wpa_psk_short)); 449 if (strpassphrase && psk) { 450 os_memcpy(strpassphrase, passphrase, passphraselen); 451 pbkdf2_sha1(strpassphrase, 452 hapd->conf->ssid.ssid, 453 hapd->conf->ssid.ssid_len, 4096, 454 psk->psk, PMK_LEN); 455 psk->next = cache->psk; 456 cache->psk = psk; 457 psk = NULL; 458 } 459 os_free(strpassphrase); 460 os_free(psk); 461 os_free(passphrase); 462 } 463 } 464 465 466 /** 467 * hostapd_acl_recv_radius - Process incoming RADIUS Authentication messages 468 * @msg: RADIUS response message 469 * @req: RADIUS request message 470 * @shared_secret: RADIUS shared secret 471 * @shared_secret_len: Length of shared_secret in octets 472 * @data: Context data (struct hostapd_data *) 473 * Returns: RADIUS_RX_PROCESSED if RADIUS message was a reply to ACL query (and 474 * was processed here) or RADIUS_RX_UNKNOWN if not. 475 */ 476 static RadiusRxResult 477 hostapd_acl_recv_radius(struct radius_msg *msg, struct radius_msg *req, 478 const u8 *shared_secret, size_t shared_secret_len, 479 void *data) 480 { 481 struct hostapd_data *hapd = data; 482 struct hostapd_acl_query_data *query, *prev; 483 struct hostapd_cached_radius_acl *cache; 484 struct radius_hdr *hdr = radius_msg_get_hdr(msg); 485 486 query = hapd->acl_queries; 487 prev = NULL; 488 while (query) { 489 if (query->radius_id == hdr->identifier) 490 break; 491 prev = query; 492 query = query->next; 493 } 494 if (query == NULL) 495 return RADIUS_RX_UNKNOWN; 496 497 wpa_printf(MSG_DEBUG, "Found matching Access-Request for RADIUS " 498 "message (id=%d)", query->radius_id); 499 500 if (radius_msg_verify(msg, shared_secret, shared_secret_len, req, 0)) { 501 wpa_printf(MSG_INFO, "Incoming RADIUS packet did not have " 502 "correct authenticator - dropped\n"); 503 return RADIUS_RX_INVALID_AUTHENTICATOR; 504 } 505 506 if (hdr->code != RADIUS_CODE_ACCESS_ACCEPT && 507 hdr->code != RADIUS_CODE_ACCESS_REJECT) { 508 wpa_printf(MSG_DEBUG, "Unknown RADIUS message code %d to ACL " 509 "query", hdr->code); 510 return RADIUS_RX_UNKNOWN; 511 } 512 513 /* Insert Accept/Reject info into ACL cache */ 514 cache = os_zalloc(sizeof(*cache)); 515 if (cache == NULL) { 516 wpa_printf(MSG_DEBUG, "Failed to add ACL cache entry"); 517 goto done; 518 } 519 os_get_reltime(&cache->timestamp); 520 os_memcpy(cache->addr, query->addr, sizeof(cache->addr)); 521 if (hdr->code == RADIUS_CODE_ACCESS_ACCEPT) { 522 u8 *buf; 523 size_t len; 524 525 if (radius_msg_get_attr_int32(msg, RADIUS_ATTR_SESSION_TIMEOUT, 526 &cache->session_timeout) == 0) 527 cache->accepted = HOSTAPD_ACL_ACCEPT_TIMEOUT; 528 else 529 cache->accepted = HOSTAPD_ACL_ACCEPT; 530 531 if (radius_msg_get_attr_int32( 532 msg, RADIUS_ATTR_ACCT_INTERIM_INTERVAL, 533 &cache->acct_interim_interval) == 0 && 534 cache->acct_interim_interval < 60) { 535 wpa_printf(MSG_DEBUG, "Ignored too small " 536 "Acct-Interim-Interval %d for STA " MACSTR, 537 cache->acct_interim_interval, 538 MAC2STR(query->addr)); 539 cache->acct_interim_interval = 0; 540 } 541 542 cache->vlan_id = radius_msg_get_vlanid(msg); 543 544 decode_tunnel_passwords(hapd, shared_secret, shared_secret_len, 545 msg, req, cache); 546 547 if (radius_msg_get_attr_ptr(msg, RADIUS_ATTR_USER_NAME, 548 &buf, &len, NULL) == 0) { 549 cache->identity = os_zalloc(len + 1); 550 if (cache->identity) 551 os_memcpy(cache->identity, buf, len); 552 } 553 if (radius_msg_get_attr_ptr( 554 msg, RADIUS_ATTR_CHARGEABLE_USER_IDENTITY, 555 &buf, &len, NULL) == 0) { 556 cache->radius_cui = os_zalloc(len + 1); 557 if (cache->radius_cui) 558 os_memcpy(cache->radius_cui, buf, len); 559 } 560 561 if (hapd->conf->wpa_psk_radius == PSK_RADIUS_REQUIRED && 562 !cache->psk) 563 cache->accepted = HOSTAPD_ACL_REJECT; 564 } else 565 cache->accepted = HOSTAPD_ACL_REJECT; 566 cache->next = hapd->acl_cache; 567 hapd->acl_cache = cache; 568 569 #ifdef CONFIG_DRIVER_RADIUS_ACL 570 hostapd_drv_set_radius_acl_auth(hapd, query->addr, cache->accepted, 571 cache->session_timeout); 572 #else /* CONFIG_DRIVER_RADIUS_ACL */ 573 #ifdef NEED_AP_MLME 574 /* Re-send original authentication frame for 802.11 processing */ 575 wpa_printf(MSG_DEBUG, "Re-sending authentication frame after " 576 "successful RADIUS ACL query"); 577 ieee802_11_mgmt(hapd, query->auth_msg, query->auth_msg_len, NULL); 578 #endif /* NEED_AP_MLME */ 579 #endif /* CONFIG_DRIVER_RADIUS_ACL */ 580 581 done: 582 if (prev == NULL) 583 hapd->acl_queries = query->next; 584 else 585 prev->next = query->next; 586 587 hostapd_acl_query_free(query); 588 589 return RADIUS_RX_PROCESSED; 590 } 591 #endif /* CONFIG_NO_RADIUS */ 592 593 594 /** 595 * hostapd_acl_init: Initialize IEEE 802.11 ACL 596 * @hapd: hostapd BSS data 597 * Returns: 0 on success, -1 on failure 598 */ 599 int hostapd_acl_init(struct hostapd_data *hapd) 600 { 601 #ifndef CONFIG_NO_RADIUS 602 if (radius_client_register(hapd->radius, RADIUS_AUTH, 603 hostapd_acl_recv_radius, hapd)) 604 return -1; 605 606 eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL); 607 #endif /* CONFIG_NO_RADIUS */ 608 609 return 0; 610 } 611 612 613 /** 614 * hostapd_acl_deinit - Deinitialize IEEE 802.11 ACL 615 * @hapd: hostapd BSS data 616 */ 617 void hostapd_acl_deinit(struct hostapd_data *hapd) 618 { 619 struct hostapd_acl_query_data *query, *prev; 620 621 #ifndef CONFIG_NO_RADIUS 622 eloop_cancel_timeout(hostapd_acl_expire, hapd, NULL); 623 624 hostapd_acl_cache_free(hapd->acl_cache); 625 #endif /* CONFIG_NO_RADIUS */ 626 627 query = hapd->acl_queries; 628 while (query) { 629 prev = query; 630 query = query->next; 631 hostapd_acl_query_free(prev); 632 } 633 } 634 635 636 void hostapd_free_psk_list(struct hostapd_sta_wpa_psk_short *psk) 637 { 638 while (psk) { 639 struct hostapd_sta_wpa_psk_short *prev = psk; 640 psk = psk->next; 641 os_free(prev); 642 } 643 } 644