wpa_supplicant/sme.c

   1 /*
   2  * wpa_supplicant - SME
   3  * Copyright (c) 2009-2010, 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 #include "common.h"
  18 #include "common/ieee802_11_defs.h"
  19 #include "common/ieee802_11_common.h"
  20 #include "eapol_supp/eapol_supp_sm.h"
  21 #include "common/wpa_common.h"
  22 #include "rsn_supp/wpa.h"
  23 #include "rsn_supp/pmksa_cache.h"
  24 #include "config.h"
  25 #include "wpa_supplicant_i.h"
  26 #include "driver_i.h"
  27 #include "wpas_glue.h"
  28 #include "wps_supplicant.h"
  29 #include "notify.h"
  30 #include "blacklist.h"
  31 #include "bss.h"
  32 #include "scan.h"
  33 #include "sme.h"
  34
  35 void sme_authenticate(struct wpa_supplicant *wpa_s,
  36                       struct wpa_bss *bss, struct wpa_ssid *ssid)
  37 {
  38         struct wpa_driver_auth_params params;
  39         struct wpa_ssid *old_ssid;
  40 #ifdef CONFIG_IEEE80211R
  41         const u8 *ie;
  42 #endif /* CONFIG_IEEE80211R */
  43 #ifdef CONFIG_IEEE80211R
  44         const u8 *md = NULL;
  45 #endif /* CONFIG_IEEE80211R */
  46         int i, bssid_changed;
  47
  48         if (bss == NULL) {
  49                 wpa_printf(MSG_ERROR, "SME: No scan result available for the "
  50                            "network");
  51                 return;
  52         }
  53
  54         wpa_s->current_bss = bss;
  55
  56         os_memset(&params, 0, sizeof(params));
  57         wpa_s->reassociate = 0;
  58
  59         params.freq = bss->freq;
  60         params.bssid = bss->bssid;
  61         params.ssid = bss->ssid;
  62         params.ssid_len = bss->ssid_len;
  63
  64         if (wpa_s->sme.ssid_len != params.ssid_len ||
  65             os_memcmp(wpa_s->sme.ssid, params.ssid, params.ssid_len) != 0)
  66                 wpa_s->sme.prev_bssid_set = 0;
  67
  68         wpa_s->sme.freq = params.freq;
  69         os_memcpy(wpa_s->sme.ssid, params.ssid, params.ssid_len);
  70         wpa_s->sme.ssid_len = params.ssid_len;
  71
  72         params.auth_alg = WPA_AUTH_ALG_OPEN;
  73 #ifdef IEEE8021X_EAPOL
  74         if (ssid->key_mgmt & WPA_KEY_MGMT_IEEE8021X_NO_WPA) {
  75                 if (ssid->leap) {
  76                         if (ssid->non_leap == 0)
  77                                 params.auth_alg = WPA_AUTH_ALG_LEAP;
  78                         else
  79                                 params.auth_alg |= WPA_AUTH_ALG_LEAP;
  80                 }
  81         }
  82 #endif /* IEEE8021X_EAPOL */
  83         wpa_printf(MSG_DEBUG, "Automatic auth_alg selection: 0x%x",
  84                    params.auth_alg);
  85         if (ssid->auth_alg) {
  86                 params.auth_alg = ssid->auth_alg;
  87                 wpa_printf(MSG_DEBUG, "Overriding auth_alg selection: 0x%x",
  88                            params.auth_alg);
  89         }
  90
  91         for (i = 0; i < NUM_WEP_KEYS; i++) {
  92                 if (ssid->wep_key_len[i])
  93                         params.wep_key[i] = ssid->wep_key[i];
  94                 params.wep_key_len[i] = ssid->wep_key_len[i];
  95         }
  96         params.wep_tx_keyidx = ssid->wep_tx_keyidx;
  97
  98         bssid_changed = !is_zero_ether_addr(wpa_s->bssid);
  99         os_memset(wpa_s->bssid, 0, ETH_ALEN);
 100         os_memcpy(wpa_s->pending_bssid, bss->bssid, ETH_ALEN);
 101         if (bssid_changed)
 102                 wpas_notify_bssid_changed(wpa_s);
 103
 104         if ((wpa_bss_get_vendor_ie(bss, WPA_IE_VENDOR_TYPE) ||
 105              wpa_bss_get_ie(bss, WLAN_EID_RSN)) &&
 106             (ssid->key_mgmt & (WPA_KEY_MGMT_IEEE8021X | WPA_KEY_MGMT_PSK |
 107                                WPA_KEY_MGMT_FT_IEEE8021X |
 108                                WPA_KEY_MGMT_FT_PSK |
 109                                WPA_KEY_MGMT_IEEE8021X_SHA256 |
 110                                WPA_KEY_MGMT_PSK_SHA256))) {
 111                 int try_opportunistic;
 112                 try_opportunistic = ssid->proactive_key_caching &&
 113                         (ssid->proto & WPA_PROTO_RSN);
 114                 if (pmksa_cache_set_current(wpa_s->wpa, NULL, bss->bssid,
 115                                             wpa_s->current_ssid,
 116                                             try_opportunistic) == 0)
 117                         eapol_sm_notify_pmkid_attempt(wpa_s->eapol, 1);
 118                 wpa_s->sme.assoc_req_ie_len = sizeof(wpa_s->sme.assoc_req_ie);
 119                 if (wpa_supplicant_set_suites(wpa_s, bss, ssid,
 120                                               wpa_s->sme.assoc_req_ie,
 121                                               &wpa_s->sme.assoc_req_ie_len)) {
 122                         wpa_printf(MSG_WARNING, "SME: Failed to set WPA key "
 123                                    "management and encryption suites");
 124                         return;
 125                 }
 126         } else if (ssid->key_mgmt &
 127                    (WPA_KEY_MGMT_PSK | WPA_KEY_MGMT_IEEE8021X |
 128                     WPA_KEY_MGMT_WPA_NONE | WPA_KEY_MGMT_FT_PSK |
 129                     WPA_KEY_MGMT_FT_IEEE8021X | WPA_KEY_MGMT_PSK_SHA256 |
 130                     WPA_KEY_MGMT_IEEE8021X_SHA256)) {
 131                 wpa_s->sme.assoc_req_ie_len = sizeof(wpa_s->sme.assoc_req_ie);
 132                 if (wpa_supplicant_set_suites(wpa_s, NULL, ssid,
 133                                               wpa_s->sme.assoc_req_ie,
 134                                               &wpa_s->sme.assoc_req_ie_len)) {
 135                         wpa_printf(MSG_WARNING, "SME: Failed to set WPA key "
 136                                    "management and encryption suites (no scan "
 137                                    "results)");
 138                         return;
 139                 }
 140 #ifdef CONFIG_WPS
 141         } else if (ssid->key_mgmt & WPA_KEY_MGMT_WPS) {
 142                 struct wpabuf *wps_ie;
 143                 wps_ie = wps_build_assoc_req_ie(wpas_wps_get_req_type(ssid));
 144                 if (wps_ie && wpabuf_len(wps_ie) <=
 145                     sizeof(wpa_s->sme.assoc_req_ie)) {
 146                         wpa_s->sme.assoc_req_ie_len = wpabuf_len(wps_ie);
 147                         os_memcpy(wpa_s->sme.assoc_req_ie, wpabuf_head(wps_ie),
 148                                   wpa_s->sme.assoc_req_ie_len);
 149                 } else
 150                         wpa_s->sme.assoc_req_ie_len = 0;
 151                 wpabuf_free(wps_ie);
 152                 wpa_supplicant_set_non_wpa_policy(wpa_s, ssid);
 153 #endif /* CONFIG_WPS */
 154         } else {
 155                 wpa_supplicant_set_non_wpa_policy(wpa_s, ssid);
 156                 wpa_s->sme.assoc_req_ie_len = 0;
 157         }
 158
 159 #ifdef CONFIG_IEEE80211R
 160         ie = wpa_bss_get_ie(bss, WLAN_EID_MOBILITY_DOMAIN);
 161         if (ie && ie[1] >= MOBILITY_DOMAIN_ID_LEN)
 162                 md = ie + 2;
 163         wpa_sm_set_ft_params(wpa_s->wpa, ie, ie ? 2 + ie[1] : 0);
 164         if (md) {
 165                 /* Prepare for the next transition */
 166                 wpa_ft_prepare_auth_request(wpa_s->wpa, ie);
 167         }
 168
 169         if (md && ssid->key_mgmt & (WPA_KEY_MGMT_FT_PSK |
 170                                     WPA_KEY_MGMT_FT_IEEE8021X)) {
 171                 if (wpa_s->sme.assoc_req_ie_len + 5 <
 172                     sizeof(wpa_s->sme.assoc_req_ie)) {
 173                         struct rsn_mdie *mdie;
 174                         u8 *pos = wpa_s->sme.assoc_req_ie +
 175                                 wpa_s->sme.assoc_req_ie_len;
 176                         *pos++ = WLAN_EID_MOBILITY_DOMAIN;
 177                         *pos++ = sizeof(*mdie);
 178                         mdie = (struct rsn_mdie *) pos;
 179                         os_memcpy(mdie->mobility_domain, md,
 180                                   MOBILITY_DOMAIN_ID_LEN);
 181                         mdie->ft_capab = md[MOBILITY_DOMAIN_ID_LEN];
 182                         wpa_s->sme.assoc_req_ie_len += 5;
 183                 }
 184
 185                 if (wpa_s->sme.ft_used &&
 186                     os_memcmp(md, wpa_s->sme.mobility_domain, 2) == 0 &&
 187                     wpa_sm_has_ptk(wpa_s->wpa)) {
 188                         wpa_printf(MSG_DEBUG, "SME: Trying to use FT "
 189                                    "over-the-air");
 190                         params.auth_alg = WPA_AUTH_ALG_FT;
 191                         params.ie = wpa_s->sme.ft_ies;
 192                         params.ie_len = wpa_s->sme.ft_ies_len;
 193                 }
 194         }
 195 #endif /* CONFIG_IEEE80211R */
 196
 197 #ifdef CONFIG_IEEE80211W
 198         wpa_s->sme.mfp = ssid->ieee80211w;
 199         if (ssid->ieee80211w != NO_MGMT_FRAME_PROTECTION) {
 200                 const u8 *rsn = wpa_bss_get_ie(bss, WLAN_EID_RSN);
 201                 struct wpa_ie_data _ie;
 202                 if (rsn && wpa_parse_wpa_ie(rsn, 2 + rsn[1], &_ie) == 0 &&
 203                     _ie.capabilities &
 204                     (WPA_CAPABILITY_MFPC | WPA_CAPABILITY_MFPR)) {
 205                         wpa_printf(MSG_DEBUG, "WPA: Selected AP supports MFP: "
 206                                    "require MFP");
 207                         wpa_s->sme.mfp = MGMT_FRAME_PROTECTION_REQUIRED;
 208                 }
 209         }
 210 #endif /* CONFIG_IEEE80211W */
 211
 212         wpa_supplicant_cancel_scan(wpa_s);
 213
 214         wpa_msg(wpa_s, MSG_INFO, "Trying to authenticate with " MACSTR
 215                 " (SSID='%s' freq=%d MHz)", MAC2STR(params.bssid),
 216                 wpa_ssid_txt(params.ssid, params.ssid_len), params.freq);
 217
 218         wpa_clear_keys(wpa_s, bss->bssid);
 219         wpa_supplicant_set_state(wpa_s, WPA_AUTHENTICATING);
 220         old_ssid = wpa_s->current_ssid;
 221         wpa_s->current_ssid = ssid;
 222         wpa_supplicant_rsn_supp_set_config(wpa_s, wpa_s->current_ssid);
 223         wpa_supplicant_initiate_eapol(wpa_s);
 224         if (old_ssid != wpa_s->current_ssid)
 225                 wpas_notify_network_changed(wpa_s);
 226
 227         wpa_s->sme.auth_alg = params.auth_alg;
 228         if (wpa_drv_authenticate(wpa_s, &params) < 0) {
 229                 wpa_msg(wpa_s, MSG_INFO, "Authentication request to the "
 230                         "driver failed");
 231                 return;
 232         }
 233
 234         /* TODO: add timeout on authentication */
 235
 236         /*
 237          * Association will be started based on the authentication event from
 238          * the driver.
 239          */
 240 }
 241
 242
 243 void sme_event_auth(struct wpa_supplicant *wpa_s, union wpa_event_data *data)
 244 {
 245         struct wpa_ssid *ssid = wpa_s->current_ssid;
 246
 247         if (ssid == NULL) {
 248                 wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
 249                            "network is not selected");
 250                 return;
 251         }
 252
 253         if (wpa_s->wpa_state != WPA_AUTHENTICATING) {
 254                 wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
 255                            "not in authenticating state");
 256                 return;
 257         }
 258
 259         if (os_memcmp(wpa_s->pending_bssid, data->auth.peer, ETH_ALEN) != 0) {
 260                 wpa_printf(MSG_DEBUG, "SME: Ignore authentication with "
 261                            "unexpected peer " MACSTR,
 262                            MAC2STR(data->auth.peer));
 263                 return;
 264         }
 265
 266         wpa_printf(MSG_DEBUG, "SME: Authentication response: peer=" MACSTR
 267                    " auth_type=%d status_code=%d",
 268                    MAC2STR(data->auth.peer), data->auth.auth_type,
 269                    data->auth.status_code);
 270         wpa_hexdump(MSG_MSGDUMP, "SME: Authentication response IEs",
 271                     data->auth.ies, data->auth.ies_len);
 272
 273         if (data->auth.status_code != WLAN_STATUS_SUCCESS) {
 274                 wpa_printf(MSG_DEBUG, "SME: Authentication failed (status "
 275                            "code %d)", data->auth.status_code);
 276                 return;
 277         }
 278
 279 #ifdef CONFIG_IEEE80211R
 280         if (data->auth.auth_type == WLAN_AUTH_FT) {
 281                 union wpa_event_data edata;
 282                 os_memset(&edata, 0, sizeof(edata));
 283                 edata.ft_ies.ies = data->auth.ies;
 284                 edata.ft_ies.ies_len = data->auth.ies_len;
 285                 os_memcpy(edata.ft_ies.target_ap, data->auth.peer, ETH_ALEN);
 286                 wpa_supplicant_event(wpa_s, EVENT_FT_RESPONSE, &edata);
 287         }
 288 #endif /* CONFIG_IEEE80211R */
 289
 290         sme_associate(wpa_s, ssid->mode, data->auth.peer,
 291                       data->auth.auth_type);
 292 }
 293
 294
 295 void sme_associate(struct wpa_supplicant *wpa_s, enum wpas_mode mode,
 296                    const u8 *bssid, u16 auth_type)
 297 {
 298         struct wpa_driver_associate_params params;
 299         struct ieee802_11_elems elems;
 300
 301         os_memset(&params, 0, sizeof(params));
 302         params.bssid = bssid;
 303         params.ssid = wpa_s->sme.ssid;
 304         params.ssid_len = wpa_s->sme.ssid_len;
 305         params.freq = wpa_s->sme.freq;
 306         params.wpa_ie = wpa_s->sme.assoc_req_ie_len ?
 307                 wpa_s->sme.assoc_req_ie : NULL;
 308         params.wpa_ie_len = wpa_s->sme.assoc_req_ie_len;
 309 #ifdef CONFIG_IEEE80211R
 310         if (auth_type == WLAN_AUTH_FT && wpa_s->sme.ft_ies) {
 311                 params.wpa_ie = wpa_s->sme.ft_ies;
 312                 params.wpa_ie_len = wpa_s->sme.ft_ies_len;
 313         }
 314 #endif /* CONFIG_IEEE80211R */
 315         params.mode = mode;
 316         params.mgmt_frame_protection = wpa_s->sme.mfp;
 317         if (wpa_s->sme.prev_bssid_set)
 318                 params.prev_bssid = wpa_s->sme.prev_bssid;
 319
 320         wpa_msg(wpa_s, MSG_INFO, "Trying to associate with " MACSTR
 321                 " (SSID='%s' freq=%d MHz)", MAC2STR(params.bssid),
 322                 params.ssid ? wpa_ssid_txt(params.ssid, params.ssid_len) : "",
 323                 params.freq);
 324
 325         wpa_supplicant_set_state(wpa_s, WPA_ASSOCIATING);
 326
 327         if (ieee802_11_parse_elems(params.wpa_ie, params.wpa_ie_len, &elems, 0)
 328             < 0) {
 329                 wpa_printf(MSG_DEBUG, "SME: Could not parse own IEs?!");
 330                 os_memset(&elems, 0, sizeof(elems));
 331         }
 332         if (elems.rsn_ie)
 333                 wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.rsn_ie - 2,
 334                                         elems.rsn_ie_len + 2);
 335         else if (elems.wpa_ie)
 336                 wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.wpa_ie - 2,
 337                                         elems.wpa_ie_len + 2);
 338         else
 339                 wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, NULL, 0);
 340
 341         if (wpa_drv_associate(wpa_s, &params) < 0) {
 342                 wpa_msg(wpa_s, MSG_INFO, "Association request to the driver "
 343                         "failed");
 344                 wpa_supplicant_req_scan(wpa_s, 5, 0);
 345                 return;
 346         }
 347
 348         /* TODO: add timeout on association */
 349 }
 350
 351
 352 int sme_update_ft_ies(struct wpa_supplicant *wpa_s, const u8 *md,
 353                       const u8 *ies, size_t ies_len)
 354 {
 355         if (md == NULL || ies == NULL) {
 356                 wpa_printf(MSG_DEBUG, "SME: Remove mobility domain");
 357                 os_free(wpa_s->sme.ft_ies);
 358                 wpa_s->sme.ft_ies = NULL;
 359                 wpa_s->sme.ft_ies_len = 0;
 360                 wpa_s->sme.ft_used = 0;
 361                 return 0;
 362         }
 363
 364         os_memcpy(wpa_s->sme.mobility_domain, md, MOBILITY_DOMAIN_ID_LEN);
 365         wpa_hexdump(MSG_DEBUG, "SME: FT IEs", ies, ies_len);
 366         os_free(wpa_s->sme.ft_ies);
 367         wpa_s->sme.ft_ies = os_malloc(ies_len);
 368         if (wpa_s->sme.ft_ies == NULL)
 369                 return -1;
 370         os_memcpy(wpa_s->sme.ft_ies, ies, ies_len);
 371         wpa_s->sme.ft_ies_len = ies_len;
 372         return 0;
 373 }
 374
 375
 376 void sme_event_assoc_reject(struct wpa_supplicant *wpa_s,
 377                             union wpa_event_data *data)
 378 {
 379         int bssid_changed;
 380         int timeout = 5000;
 381
 382         wpa_printf(MSG_DEBUG, "SME: Association with " MACSTR " failed: "
 383                    "status code %d", MAC2STR(wpa_s->pending_bssid),
 384                    data->assoc_reject.status_code);
 385
 386         bssid_changed = !is_zero_ether_addr(wpa_s->bssid);
 387
 388         /*
 389          * For now, unconditionally terminate the previous authentication. In
 390          * theory, this should not be needed, but mac80211 gets quite confused
 391          * if the authentication is left pending.. Some roaming cases might
 392          * benefit from using the previous authentication, so this could be
 393          * optimized in the future.
 394          */
 395         if (wpa_drv_deauthenticate(wpa_s, wpa_s->pending_bssid,
 396                                    WLAN_REASON_DEAUTH_LEAVING) < 0) {
 397                 wpa_msg(wpa_s, MSG_INFO,
 398                         "Deauth request to the driver failed");
 399         }
 400         wpa_s->sme.prev_bssid_set = 0;
 401
 402         if (wpa_blacklist_add(wpa_s, wpa_s->pending_bssid) == 0) {
 403                 struct wpa_blacklist *b;
 404                 b = wpa_blacklist_get(wpa_s, wpa_s->pending_bssid);
 405                 if (b && b->count < 3) {
 406                         /*
 407                          * Speed up next attempt if there could be other APs
 408                          * that could accept association.
 409                          */
 410                         timeout = 100;
 411                 }
 412         }
 413         wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 414         os_memset(wpa_s->bssid, 0, ETH_ALEN);
 415         os_memset(wpa_s->pending_bssid, 0, ETH_ALEN);
 416         if (bssid_changed)
 417                 wpas_notify_bssid_changed(wpa_s);
 418
 419         /*
 420          * TODO: if more than one possible AP is available in scan results,
 421          * could try the other ones before requesting a new scan.
 422          */
 423         wpa_supplicant_req_scan(wpa_s, timeout / 1000,
 424                                 1000 * (timeout % 1000));
 425 }
 426
 427
 428 void sme_event_auth_timed_out(struct wpa_supplicant *wpa_s,
 429                               union wpa_event_data *data)
 430 {
 431         wpa_printf(MSG_DEBUG, "SME: Authentication timed out");
 432         wpa_supplicant_req_scan(wpa_s, 5, 0);
 433 }
 434
 435
 436 void sme_event_assoc_timed_out(struct wpa_supplicant *wpa_s,
 437                                union wpa_event_data *data)
 438 {
 439         wpa_printf(MSG_DEBUG, "SME: Association timed out");
 440         wpa_supplicant_mark_disassoc(wpa_s);
 441         wpa_supplicant_req_scan(wpa_s, 5, 0);
 442 }
 443
 444
 445 void sme_event_disassoc(struct wpa_supplicant *wpa_s,
 446                         union wpa_event_data *data)
 447 {
 448         wpa_printf(MSG_DEBUG, "SME: Disassociation event received");
 449         if (!is_zero_ether_addr(wpa_s->bssid) &&
 450             !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)) {
 451                 /*
 452                  * cfg80211/mac80211 can get into somewhat confused state if
 453                  * the AP only disassociates us and leaves us in authenticated
 454                  * state. For now, force the state to be cleared to avoid
 455                  * confusing errors if we try to associate with the AP again.
 456                  */
 457                 wpa_printf(MSG_DEBUG, "SME: Deauthenticate to clear driver "
 458                            "state");
 459                 wpa_drv_deauthenticate(wpa_s, wpa_s->bssid,
 460                                        WLAN_REASON_DEAUTH_LEAVING);
 461         }
 462 }