contrib/hostapd/ieee802_11_auth.c

   1 /*
   2  * hostapd / IEEE 802.11 authentication (ACL)
   3  * Copyright (c) 2003-2006, Jouni Malinen <j@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 #ifndef CONFIG_NATIVE_WINDOWS
  18
  19 #include "hostapd.h"
  20 #include "ieee802_11.h"
  21 #include "ieee802_11_auth.h"
  22 #include "radius.h"
  23 #include "radius_client.h"
  24 #include "eloop.h"
  25
  26 #define RADIUS_ACL_TIMEOUT 30
  27
  28
  29 struct hostapd_cached_radius_acl {
  30         time_t timestamp;
  31         macaddr addr;
  32         int accepted; /* HOSTAPD_ACL_* */
  33         struct hostapd_cached_radius_acl *next;
  34         u32 session_timeout;
  35         u32 acct_interim_interval;
  36         int vlan_id;
  37 };
  38
  39
  40 struct hostapd_acl_query_data {
  41         time_t timestamp;
  42         u8 radius_id;
  43         macaddr addr;
  44         u8 *auth_msg; /* IEEE 802.11 authentication frame from station */
  45         size_t auth_msg_len;
  46         struct hostapd_acl_query_data *next;
  47 };
  48
  49
  50 static void hostapd_acl_cache_free(struct hostapd_cached_radius_acl *acl_cache)
  51 {
  52         struct hostapd_cached_radius_acl *prev;
  53
  54         while (acl_cache) {
  55                 prev = acl_cache;
  56                 acl_cache = acl_cache->next;
  57                 free(prev);
  58         }
  59 }
  60
  61
  62 static int hostapd_acl_cache_get(struct hostapd_data *hapd, const u8 *addr,
  63                                  u32 *session_timeout,
  64                                  u32 *acct_interim_interval, int *vlan_id)
  65 {
  66         struct hostapd_cached_radius_acl *entry;
  67         time_t now;
  68
  69         time(&now);
  70         entry = hapd->acl_cache;
  71
  72         while (entry) {
  73                 if (memcmp(entry->addr, addr, ETH_ALEN) == 0) {
  74                         if (now - entry->timestamp > RADIUS_ACL_TIMEOUT)
  75                                 return -1; /* entry has expired */
  76                         if (entry->accepted == HOSTAPD_ACL_ACCEPT_TIMEOUT)
  77                                 *session_timeout = entry->session_timeout;
  78                         *acct_interim_interval = entry->acct_interim_interval;
  79                         if (vlan_id)
  80                                 *vlan_id = entry->vlan_id;
  81                         return entry->accepted;
  82                 }
  83
  84                 entry = entry->next;
  85         }
  86
  87         return -1;
  88 }
  89
  90
  91 static void hostapd_acl_query_free(struct hostapd_acl_query_data *query)
  92 {
  93         if (query == NULL)
  94                 return;
  95         free(query->auth_msg);
  96         free(query);
  97 }
  98
  99
 100 static int hostapd_radius_acl_query(struct hostapd_data *hapd, const u8 *addr,
 101                                     struct hostapd_acl_query_data *query)
 102 {
 103         struct radius_msg *msg;
 104         char buf[128];
 105
 106         query->radius_id = radius_client_get_id(hapd->radius);
 107         msg = radius_msg_new(RADIUS_CODE_ACCESS_REQUEST, query->radius_id);
 108         if (msg == NULL)
 109                 return -1;
 110
 111         radius_msg_make_authenticator(msg, addr, ETH_ALEN);
 112
 113         snprintf(buf, sizeof(buf), RADIUS_ADDR_FORMAT, MAC2STR(addr));
 114         if (!radius_msg_add_attr(msg, RADIUS_ATTR_USER_NAME, (u8 *) buf,
 115                                  strlen(buf))) {
 116                 printf("Could not add User-Name\n");
 117                 goto fail;
 118         }
 119
 120         if (!radius_msg_add_attr_user_password(
 121                     msg, (u8 *) buf, strlen(buf),
 122                     hapd->conf->radius->auth_server->shared_secret,
 123                     hapd->conf->radius->auth_server->shared_secret_len)) {
 124                 printf("Could not add User-Password\n");
 125                 goto fail;
 126         }
 127
 128         if (hapd->conf->own_ip_addr.af == AF_INET &&
 129             !radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IP_ADDRESS,
 130                                  (u8 *) &hapd->conf->own_ip_addr.u.v4, 4)) {
 131                 printf("Could not add NAS-IP-Address\n");
 132                 goto fail;
 133         }
 134
 135 #ifdef CONFIG_IPV6
 136         if (hapd->conf->own_ip_addr.af == AF_INET6 &&
 137             !radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IPV6_ADDRESS,
 138                                  (u8 *) &hapd->conf->own_ip_addr.u.v6, 16)) {
 139                 printf("Could not add NAS-IPv6-Address\n");
 140                 goto fail;
 141         }
 142 #endif /* CONFIG_IPV6 */
 143
 144         if (hapd->conf->nas_identifier &&
 145             !radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IDENTIFIER,
 146                                  (u8 *) hapd->conf->nas_identifier,
 147                                  strlen(hapd->conf->nas_identifier))) {
 148                 printf("Could not add NAS-Identifier\n");
 149                 goto fail;
 150         }
 151
 152         snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT ":%s",
 153                  MAC2STR(hapd->own_addr), hapd->conf->ssid.ssid);
 154         if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLED_STATION_ID,
 155                                  (u8 *) buf, strlen(buf))) {
 156                 printf("Could not add Called-Station-Id\n");
 157                 goto fail;
 158         }
 159
 160         snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT,
 161                  MAC2STR(addr));
 162         if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLING_STATION_ID,
 163                                  (u8 *) buf, strlen(buf))) {
 164                 printf("Could not add Calling-Station-Id\n");
 165                 goto fail;
 166         }
 167
 168         if (!radius_msg_add_attr_int32(msg, RADIUS_ATTR_NAS_PORT_TYPE,
 169                                        RADIUS_NAS_PORT_TYPE_IEEE_802_11)) {
 170                 printf("Could not add NAS-Port-Type\n");
 171                 goto fail;
 172         }
 173
 174         snprintf(buf, sizeof(buf), "CONNECT 11Mbps 802.11b");
 175         if (!radius_msg_add_attr(msg, RADIUS_ATTR_CONNECT_INFO,
 176                                  (u8 *) buf, strlen(buf))) {
 177                 printf("Could not add Connect-Info\n");
 178                 goto fail;
 179         }
 180
 181         radius_client_send(hapd->radius, msg, RADIUS_AUTH, addr);
 182         return 0;
 183
 184  fail:
 185         radius_msg_free(msg);
 186         free(msg);
 187         return -1;
 188 }
 189
 190
 191 int hostapd_allowed_address(struct hostapd_data *hapd, const u8 *addr,
 192                             const u8 *msg, size_t len, u32 *session_timeout,
 193                             u32 *acct_interim_interval, int *vlan_id)
 194 {
 195         *session_timeout = 0;
 196         *acct_interim_interval = 0;
 197         if (vlan_id)
 198                 *vlan_id = 0;
 199
 200         if (hostapd_maclist_found(hapd->conf->accept_mac,
 201                                   hapd->conf->num_accept_mac, addr))
 202                 return HOSTAPD_ACL_ACCEPT;
 203
 204         if (hostapd_maclist_found(hapd->conf->deny_mac,
 205                                   hapd->conf->num_deny_mac, addr))
 206                 return HOSTAPD_ACL_REJECT;
 207
 208         if (hapd->conf->macaddr_acl == ACCEPT_UNLESS_DENIED)
 209                 return HOSTAPD_ACL_ACCEPT;
 210         if (hapd->conf->macaddr_acl == DENY_UNLESS_ACCEPTED)
 211                 return HOSTAPD_ACL_REJECT;
 212
 213         if (hapd->conf->macaddr_acl == USE_EXTERNAL_RADIUS_AUTH) {
 214                 struct hostapd_acl_query_data *query;
 215
 216                 /* Check whether ACL cache has an entry for this station */
 217                 int res = hostapd_acl_cache_get(hapd, addr, session_timeout,
 218                                                 acct_interim_interval,
 219                                                 vlan_id);
 220                 if (res == HOSTAPD_ACL_ACCEPT ||
 221                     res == HOSTAPD_ACL_ACCEPT_TIMEOUT)
 222                         return res;
 223                 if (res == HOSTAPD_ACL_REJECT)
 224                         return HOSTAPD_ACL_REJECT;
 225
 226                 query = hapd->acl_queries;
 227                 while (query) {
 228                         if (memcmp(query->addr, addr, ETH_ALEN) == 0) {
 229                                 /* pending query in RADIUS retransmit queue;
 230                                  * do not generate a new one */
 231                                 return HOSTAPD_ACL_PENDING;
 232                         }
 233                         query = query->next;
 234                 }
 235
 236                 if (!hapd->conf->radius->auth_server)
 237                         return HOSTAPD_ACL_REJECT;
 238
 239                 /* No entry in the cache - query external RADIUS server */
 240                 query = wpa_zalloc(sizeof(*query));
 241                 if (query == NULL) {
 242                         printf("malloc for query data failed\n");
 243                         return HOSTAPD_ACL_REJECT;
 244                 }
 245                 time(&query->timestamp);
 246                 memcpy(query->addr, addr, ETH_ALEN);
 247                 if (hostapd_radius_acl_query(hapd, addr, query)) {
 248                         printf("Failed to send Access-Request for ACL "
 249                                "query.\n");
 250                         hostapd_acl_query_free(query);
 251                         return HOSTAPD_ACL_REJECT;
 252                 }
 253
 254                 query->auth_msg = malloc(len);
 255                 if (query->auth_msg == NULL) {
 256                         printf("Failed to allocate memory for auth frame.\n");
 257                         hostapd_acl_query_free(query);
 258                         return HOSTAPD_ACL_REJECT;
 259                 }
 260                 memcpy(query->auth_msg, msg, len);
 261                 query->auth_msg_len = len;
 262                 query->next = hapd->acl_queries;
 263                 hapd->acl_queries = query;
 264
 265                 /* Queued data will be processed in hostapd_acl_recv_radius()
 266                  * when RADIUS server replies to the sent Access-Request. */
 267                 return HOSTAPD_ACL_PENDING;
 268         }
 269
 270         return HOSTAPD_ACL_REJECT;
 271 }
 272
 273
 274 static void hostapd_acl_expire_cache(struct hostapd_data *hapd, time_t now)
 275 {
 276         struct hostapd_cached_radius_acl *prev, *entry, *tmp;
 277
 278         prev = NULL;
 279         entry = hapd->acl_cache;
 280
 281         while (entry) {
 282                 if (now - entry->timestamp > RADIUS_ACL_TIMEOUT) {
 283                         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
 284                                       "Cached ACL entry for " MACSTR
 285                                       " has expired.\n", MAC2STR(entry->addr));
 286                         if (prev)
 287                                 prev->next = entry->next;
 288                         else
 289                                 hapd->acl_cache = entry->next;
 290
 291                         tmp = entry;
 292                         entry = entry->next;
 293                         free(tmp);
 294                         continue;
 295                 }
 296
 297                 prev = entry;
 298                 entry = entry->next;
 299         }
 300 }
 301
 302
 303 static void hostapd_acl_expire_queries(struct hostapd_data *hapd, time_t now)
 304 {
 305         struct hostapd_acl_query_data *prev, *entry, *tmp;
 306
 307         prev = NULL;
 308         entry = hapd->acl_queries;
 309
 310         while (entry) {
 311                 if (now - entry->timestamp > RADIUS_ACL_TIMEOUT) {
 312                         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
 313                                       "ACL query for " MACSTR
 314                                       " has expired.\n", MAC2STR(entry->addr));
 315                         if (prev)
 316                                 prev->next = entry->next;
 317                         else
 318                                 hapd->acl_queries = entry->next;
 319
 320                         tmp = entry;
 321                         entry = entry->next;
 322                         hostapd_acl_query_free(tmp);
 323                         continue;
 324                 }
 325
 326                 prev = entry;
 327                 entry = entry->next;
 328         }
 329 }
 330
 331
 332 static void hostapd_acl_expire(void *eloop_ctx, void *timeout_ctx)
 333 {
 334         struct hostapd_data *hapd = eloop_ctx;
 335         time_t now;
 336
 337         time(&now);
 338         hostapd_acl_expire_cache(hapd, now);
 339         hostapd_acl_expire_queries(hapd, now);
 340
 341         eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL);
 342 }
 343
 344
 345 /* Return 0 if RADIUS message was a reply to ACL query (and was processed here)
 346  * or -1 if not. */
 347 static RadiusRxResult
 348 hostapd_acl_recv_radius(struct radius_msg *msg, struct radius_msg *req,
 349                         u8 *shared_secret, size_t shared_secret_len,
 350                         void *data)
 351 {
 352         struct hostapd_data *hapd = data;
 353         struct hostapd_acl_query_data *query, *prev;
 354         struct hostapd_cached_radius_acl *cache;
 355
 356         query = hapd->acl_queries;
 357         prev = NULL;
 358         while (query) {
 359                 if (query->radius_id == msg->hdr->identifier)
 360                         break;
 361                 prev = query;
 362                 query = query->next;
 363         }
 364         if (query == NULL)
 365                 return RADIUS_RX_UNKNOWN;
 366
 367         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Found matching Access-Request "
 368                       "for RADIUS message (id=%d)\n", query->radius_id);
 369
 370         if (radius_msg_verify(msg, shared_secret, shared_secret_len, req, 0)) {
 371                 printf("Incoming RADIUS packet did not have correct "
 372                        "authenticator - dropped\n");
 373                 return RADIUS_RX_INVALID_AUTHENTICATOR;
 374         }
 375
 376         if (msg->hdr->code != RADIUS_CODE_ACCESS_ACCEPT &&
 377             msg->hdr->code != RADIUS_CODE_ACCESS_REJECT) {
 378                 printf("Unknown RADIUS message code %d to ACL query\n",
 379                        msg->hdr->code);
 380                 return RADIUS_RX_UNKNOWN;
 381         }
 382
 383         /* Insert Accept/Reject info into ACL cache */
 384         cache = wpa_zalloc(sizeof(*cache));
 385         if (cache == NULL) {
 386                 printf("Failed to add ACL cache entry\n");
 387                 goto done;
 388         }
 389         time(&cache->timestamp);
 390         memcpy(cache->addr, query->addr, sizeof(cache->addr));
 391         if (msg->hdr->code == RADIUS_CODE_ACCESS_ACCEPT) {
 392                 if (radius_msg_get_attr_int32(msg, RADIUS_ATTR_SESSION_TIMEOUT,
 393                                               &cache->session_timeout) == 0)
 394                         cache->accepted = HOSTAPD_ACL_ACCEPT_TIMEOUT;
 395                 else
 396                         cache->accepted = HOSTAPD_ACL_ACCEPT;
 397
 398                 if (radius_msg_get_attr_int32(
 399                             msg, RADIUS_ATTR_ACCT_INTERIM_INTERVAL,
 400                             &cache->acct_interim_interval) == 0 &&
 401                     cache->acct_interim_interval < 60) {
 402                         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Ignored too "
 403                                       "small Acct-Interim-Interval %d for "
 404                                       "STA " MACSTR "\n",
 405                                       cache->acct_interim_interval,
 406                                       MAC2STR(query->addr));
 407                         cache->acct_interim_interval = 0;
 408                 }
 409
 410                 cache->vlan_id = radius_msg_get_vlanid(msg);
 411         } else
 412                 cache->accepted = HOSTAPD_ACL_REJECT;
 413         cache->next = hapd->acl_cache;
 414         hapd->acl_cache = cache;
 415
 416         /* Re-send original authentication frame for 802.11 processing */
 417         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Re-sending authentication frame "
 418                       "after successful RADIUS ACL query\n");
 419         ieee802_11_mgmt(hapd, query->auth_msg, query->auth_msg_len,
 420                         WLAN_FC_STYPE_AUTH, NULL);
 421
 422  done:
 423         if (prev == NULL)
 424                 hapd->acl_queries = query->next;
 425         else
 426                 prev->next = query->next;
 427
 428         hostapd_acl_query_free(query);
 429
 430         return RADIUS_RX_PROCESSED;
 431 }
 432
 433
 434 int hostapd_acl_init(struct hostapd_data *hapd)
 435 {
 436         if (radius_client_register(hapd->radius, RADIUS_AUTH,
 437                                    hostapd_acl_recv_radius, hapd))
 438                 return -1;
 439
 440         eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL);
 441
 442         return 0;
 443 }
 444
 445
 446 void hostapd_acl_deinit(struct hostapd_data *hapd)
 447 {
 448         struct hostapd_acl_query_data *query, *prev;
 449
 450         eloop_cancel_timeout(hostapd_acl_expire, hapd, NULL);
 451
 452         hostapd_acl_cache_free(hapd->acl_cache);
 453
 454         query = hapd->acl_queries;
 455         while (query) {
 456                 prev = query;
 457                 query = query->next;
 458                 hostapd_acl_query_free(prev);
 459         }
 460 }
 461
 462
 463 int hostapd_acl_reconfig(struct hostapd_data *hapd,
 464                          struct hostapd_config *oldconf)
 465 {
 466         if (!hapd->radius_client_reconfigured)
 467                 return 0;
 468
 469         hostapd_acl_deinit(hapd);
 470         return hostapd_acl_init(hapd);
 471 }
 472
 473 #endif /* CONFIG_NATIVE_WINDOWS */