wpa_supplicant: sme.c Source File

00001 /*
00002  * wpa_supplicant - SME
00003  * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
00004  *
00005  * This program is free software; you can redistribute it and/or modify
00006  * it under the terms of the GNU General Public License version 2 as
00007  * published by the Free Software Foundation.
00008  *
00009  * Alternatively, this software may be distributed under the terms of BSD
00010  * license.
00011  *
00012  * See README and COPYING for more details.
00013  */
00014 
00015 #include "includes.h"
00016 
00017 #include "common.h"
00018 #include "common/ieee802_11_defs.h"
00019 #include "common/ieee802_11_common.h"
00020 #include "eapol_supp/eapol_supp_sm.h"
00021 #include "common/wpa_common.h"
00022 #include "rsn_supp/wpa.h"
00023 #include "rsn_supp/pmksa_cache.h"
00024 #include "config.h"
00025 #include "wpa_supplicant_i.h"
00026 #include "driver_i.h"
00027 #include "wpas_glue.h"
00028 #include "wps_supplicant.h"
00029 #include "notify.h"
00030 #include "blacklist.h"
00031 #include "bss.h"
00032 #include "scan.h"
00033 #include "sme.h"
00034 
00035 void sme_authenticate(struct wpa_supplicant *wpa_s,
00036                       struct wpa_bss *bss, struct wpa_ssid *ssid)
00037 {
00038         struct wpa_driver_auth_params params;
00039         struct wpa_ssid *old_ssid;
00040 #ifdef CONFIG_IEEE80211R
00041         const u8 *ie;
00042 #endif /* CONFIG_IEEE80211R */
00043 #ifdef CONFIG_IEEE80211R
00044         const u8 *md = NULL;
00045 #endif /* CONFIG_IEEE80211R */
00046         int i, bssid_changed;
00047 
00048         if (bss == NULL) {
00049                 wpa_printf(MSG_ERROR, "SME: No scan result available for the "
00050                            "network");
00051                 return;
00052         }
00053 
00054         wpa_s->current_bss = bss;
00055 
00056         os_memset(&params, 0, sizeof(params));
00057         wpa_s->reassociate = 0;
00058 
00059         params.freq = bss->freq;
00060         params.bssid = bss->bssid;
00061         params.ssid = bss->ssid;
00062         params.ssid_len = bss->ssid_len;
00063 
00064         if (wpa_s->sme.ssid_len != params.ssid_len ||
00065             os_memcmp(wpa_s->sme.ssid, params.ssid, params.ssid_len) != 0)
00066                 wpa_s->sme.prev_bssid_set = 0;
00067 
00068         wpa_s->sme.freq = params.freq;
00069         os_memcpy(wpa_s->sme.ssid, params.ssid, params.ssid_len);
00070         wpa_s->sme.ssid_len = params.ssid_len;
00071 
00072         params.auth_alg = WPA_AUTH_ALG_OPEN;
00073 #ifdef IEEE8021X_EAPOL
00074         if (ssid->key_mgmt & WPA_KEY_MGMT_IEEE8021X_NO_WPA) {
00075                 if (ssid->leap) {
00076                         if (ssid->non_leap == 0)
00077                                 params.auth_alg = WPA_AUTH_ALG_LEAP;
00078                         else
00079                                 params.auth_alg |= WPA_AUTH_ALG_LEAP;
00080                 }
00081         }
00082 #endif /* IEEE8021X_EAPOL */
00083         wpa_printf(MSG_DEBUG, "Automatic auth_alg selection: 0x%x",
00084                    params.auth_alg);
00085         if (ssid->auth_alg) {
00086                 params.auth_alg = ssid->auth_alg;
00087                 wpa_printf(MSG_DEBUG, "Overriding auth_alg selection: 0x%x",
00088                            params.auth_alg);
00089         }
00090 
00091         for (i = 0; i < NUM_WEP_KEYS; i++) {
00092                 if (ssid->wep_key_len[i])
00093                         params.wep_key[i] = ssid->wep_key[i];
00094                 params.wep_key_len[i] = ssid->wep_key_len[i];
00095         }
00096         params.wep_tx_keyidx = ssid->wep_tx_keyidx;
00097 
00098         bssid_changed = !is_zero_ether_addr(wpa_s->bssid);
00099         os_memset(wpa_s->bssid, 0, ETH_ALEN);
00100         os_memcpy(wpa_s->pending_bssid, bss->bssid, ETH_ALEN);
00101         if (bssid_changed)
00102                 wpas_notify_bssid_changed(wpa_s);
00103 
00104         if ((wpa_bss_get_vendor_ie(bss, WPA_IE_VENDOR_TYPE) ||
00105              wpa_bss_get_ie(bss, WLAN_EID_RSN)) &&
00106             (ssid->key_mgmt & (WPA_KEY_MGMT_IEEE8021X | WPA_KEY_MGMT_PSK |
00107                                WPA_KEY_MGMT_FT_IEEE8021X |
00108                                WPA_KEY_MGMT_FT_PSK |
00109                                WPA_KEY_MGMT_IEEE8021X_SHA256 |
00110                                WPA_KEY_MGMT_PSK_SHA256))) {
00111                 int try_opportunistic;
00112                 try_opportunistic = ssid->proactive_key_caching &&
00113                         (ssid->proto & WPA_PROTO_RSN);
00114                 if (pmksa_cache_set_current(wpa_s->wpa, NULL, bss->bssid,
00115                                             wpa_s->current_ssid,
00116                                             try_opportunistic) == 0)
00117                         eapol_sm_notify_pmkid_attempt(wpa_s->eapol, 1);
00118                 wpa_s->sme.assoc_req_ie_len = sizeof(wpa_s->sme.assoc_req_ie);
00119                 if (wpa_supplicant_set_suites(wpa_s, bss, ssid,
00120                                               wpa_s->sme.assoc_req_ie,
00121                                               &wpa_s->sme.assoc_req_ie_len)) {
00122                         wpa_printf(MSG_WARNING, "SME: Failed to set WPA key "
00123                                    "management and encryption suites");
00124                         return;
00125                 }
00126         } else if (ssid->key_mgmt &
00127                    (WPA_KEY_MGMT_PSK | WPA_KEY_MGMT_IEEE8021X |
00128                     WPA_KEY_MGMT_WPA_NONE | WPA_KEY_MGMT_FT_PSK |
00129                     WPA_KEY_MGMT_FT_IEEE8021X | WPA_KEY_MGMT_PSK_SHA256 |
00130                     WPA_KEY_MGMT_IEEE8021X_SHA256)) {
00131                 wpa_s->sme.assoc_req_ie_len = sizeof(wpa_s->sme.assoc_req_ie);
00132                 if (wpa_supplicant_set_suites(wpa_s, NULL, ssid,
00133                                               wpa_s->sme.assoc_req_ie,
00134                                               &wpa_s->sme.assoc_req_ie_len)) {
00135                         wpa_printf(MSG_WARNING, "SME: Failed to set WPA key "
00136                                    "management and encryption suites (no scan "
00137                                    "results)");
00138                         return;
00139                 }
00140 #ifdef CONFIG_WPS
00141         } else if (ssid->key_mgmt & WPA_KEY_MGMT_WPS) {
00142                 struct wpabuf *wps_ie;
00143                 wps_ie = wps_build_assoc_req_ie(wpas_wps_get_req_type(ssid));
00144                 if (wps_ie && wpabuf_len(wps_ie) <=
00145                     sizeof(wpa_s->sme.assoc_req_ie)) {
00146                         wpa_s->sme.assoc_req_ie_len = wpabuf_len(wps_ie);
00147                         os_memcpy(wpa_s->sme.assoc_req_ie, wpabuf_head(wps_ie),
00148                                   wpa_s->sme.assoc_req_ie_len);
00149                 } else
00150                         wpa_s->sme.assoc_req_ie_len = 0;
00151                 wpabuf_free(wps_ie);
00152                 wpa_supplicant_set_non_wpa_policy(wpa_s, ssid);
00153 #endif /* CONFIG_WPS */
00154         } else {
00155                 wpa_supplicant_set_non_wpa_policy(wpa_s, ssid);
00156                 wpa_s->sme.assoc_req_ie_len = 0;
00157         }
00158 
00159 #ifdef CONFIG_IEEE80211R
00160         ie = wpa_bss_get_ie(bss, WLAN_EID_MOBILITY_DOMAIN);
00161         if (ie && ie[1] >= MOBILITY_DOMAIN_ID_LEN)
00162                 md = ie + 2;
00163         wpa_sm_set_ft_params(wpa_s->wpa, ie, ie ? 2 + ie[1] : 0);
00164         if (md) {
00165                 /* Prepare for the next transition */
00166                 wpa_ft_prepare_auth_request(wpa_s->wpa, ie);
00167         }
00168 
00169         if (md && ssid->key_mgmt & (WPA_KEY_MGMT_FT_PSK |
00170                                     WPA_KEY_MGMT_FT_IEEE8021X)) {
00171                 if (wpa_s->sme.assoc_req_ie_len + 5 <
00172                     sizeof(wpa_s->sme.assoc_req_ie)) {
00173                         struct rsn_mdie *mdie;
00174                         u8 *pos = wpa_s->sme.assoc_req_ie +
00175                                 wpa_s->sme.assoc_req_ie_len;
00176                         *pos++ = WLAN_EID_MOBILITY_DOMAIN;
00177                         *pos++ = sizeof(*mdie);
00178                         mdie = (struct rsn_mdie *) pos;
00179                         os_memcpy(mdie->mobility_domain, md,
00180                                   MOBILITY_DOMAIN_ID_LEN);
00181                         mdie->ft_capab = md[MOBILITY_DOMAIN_ID_LEN];
00182                         wpa_s->sme.assoc_req_ie_len += 5;
00183                 }
00184 
00185                 if (wpa_s->sme.ft_used &&
00186                     os_memcmp(md, wpa_s->sme.mobility_domain, 2) == 0 &&
00187                     wpa_sm_has_ptk(wpa_s->wpa)) {
00188                         wpa_printf(MSG_DEBUG, "SME: Trying to use FT "
00189                                    "over-the-air");
00190                         params.auth_alg = WPA_AUTH_ALG_FT;
00191                         params.ie = wpa_s->sme.ft_ies;
00192                         params.ie_len = wpa_s->sme.ft_ies_len;
00193                 }
00194         }
00195 #endif /* CONFIG_IEEE80211R */
00196 
00197 #ifdef CONFIG_IEEE80211W
00198         wpa_s->sme.mfp = ssid->ieee80211w;
00199         if (ssid->ieee80211w != NO_MGMT_FRAME_PROTECTION) {
00200                 const u8 *rsn = wpa_bss_get_ie(bss, WLAN_EID_RSN);
00201                 struct wpa_ie_data _ie;
00202                 if (rsn && wpa_parse_wpa_ie(rsn, 2 + rsn[1], &_ie) == 0 &&
00203                     _ie.capabilities &
00204                     (WPA_CAPABILITY_MFPC | WPA_CAPABILITY_MFPR)) {
00205                         wpa_printf(MSG_DEBUG, "WPA: Selected AP supports MFP: "
00206                                    "require MFP");
00207                         wpa_s->sme.mfp = MGMT_FRAME_PROTECTION_REQUIRED;
00208                 }
00209         }
00210 #endif /* CONFIG_IEEE80211W */
00211 
00212         wpa_supplicant_cancel_scan(wpa_s);
00213 
00214         wpa_msg(wpa_s, MSG_INFO, "Trying to authenticate with " MACSTR
00215                 " (SSID='%s' freq=%d MHz)", MAC2STR(params.bssid),
00216                 wpa_ssid_txt(params.ssid, params.ssid_len), params.freq);
00217 
00218         wpa_clear_keys(wpa_s, bss->bssid);
00219         wpa_supplicant_set_state(wpa_s, WPA_AUTHENTICATING);
00220         old_ssid = wpa_s->current_ssid;
00221         wpa_s->current_ssid = ssid;
00222         wpa_supplicant_rsn_supp_set_config(wpa_s, wpa_s->current_ssid);
00223         wpa_supplicant_initiate_eapol(wpa_s);
00224         if (old_ssid != wpa_s->current_ssid)
00225                 wpas_notify_network_changed(wpa_s);
00226 
00227         wpa_s->sme.auth_alg = params.auth_alg;
00228         if (wpa_drv_authenticate(wpa_s, &params) < 0) {
00229                 wpa_msg(wpa_s, MSG_INFO, "Authentication request to the "
00230                         "driver failed");
00231                 wpa_supplicant_req_scan(wpa_s, 0, 200000);
00232                 return;
00233         }
00234 
00235         /* TODO: add timeout on authentication */
00236 
00237         /*
00238          * Association will be started based on the authentication event from
00239          * the driver.
00240          */
00241 }
00242 
00243 
00244 void sme_event_auth(struct wpa_supplicant *wpa_s, union wpa_event_data *data)
00245 {
00246         struct wpa_ssid *ssid = wpa_s->current_ssid;
00247 
00248         if (ssid == NULL) {
00249                 wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
00250                            "network is not selected");
00251                 return;
00252         }
00253 
00254         if (wpa_s->wpa_state != WPA_AUTHENTICATING) {
00255                 wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
00256                            "not in authenticating state");
00257                 return;
00258         }
00259 
00260         if (os_memcmp(wpa_s->pending_bssid, data->auth.peer, ETH_ALEN) != 0) {
00261                 wpa_printf(MSG_DEBUG, "SME: Ignore authentication with "
00262                            "unexpected peer " MACSTR,
00263                            MAC2STR(data->auth.peer));
00264                 return;
00265         }
00266 
00267         wpa_printf(MSG_DEBUG, "SME: Authentication response: peer=" MACSTR
00268                    " auth_type=%d status_code=%d",
00269                    MAC2STR(data->auth.peer), data->auth.auth_type,
00270                    data->auth.status_code);
00271         wpa_hexdump(MSG_MSGDUMP, "SME: Authentication response IEs",
00272                     data->auth.ies, data->auth.ies_len);
00273 
00274         if (data->auth.status_code != WLAN_STATUS_SUCCESS) {
00275                 wpa_printf(MSG_DEBUG, "SME: Authentication failed (status "
00276                            "code %d)", data->auth.status_code);
00277                 return;
00278         }
00279 
00280 #ifdef CONFIG_IEEE80211R
00281         if (data->auth.auth_type == WLAN_AUTH_FT) {
00282                 union wpa_event_data edata;
00283                 os_memset(&edata, 0, sizeof(edata));
00284                 edata.ft_ies.ies = data->auth.ies;
00285                 edata.ft_ies.ies_len = data->auth.ies_len;
00286                 os_memcpy(edata.ft_ies.target_ap, data->auth.peer, ETH_ALEN);
00287                 wpa_supplicant_event(wpa_s, EVENT_FT_RESPONSE, &edata);
00288         }
00289 #endif /* CONFIG_IEEE80211R */
00290 
00291         sme_associate(wpa_s, ssid->mode, data->auth.peer,
00292                       data->auth.auth_type);
00293 }
00294 
00295 
00296 void sme_associate(struct wpa_supplicant *wpa_s, enum wpas_mode mode,
00297                    const u8 *bssid, u16 auth_type)
00298 {
00299         struct wpa_driver_associate_params params;
00300         struct ieee802_11_elems elems;
00301 
00302         os_memset(&params, 0, sizeof(params));
00303         params.bssid = bssid;
00304         params.ssid = wpa_s->sme.ssid;
00305         params.ssid_len = wpa_s->sme.ssid_len;
00306         params.freq = wpa_s->sme.freq;
00307         params.wpa_ie = wpa_s->sme.assoc_req_ie_len ?
00308                 wpa_s->sme.assoc_req_ie : NULL;
00309         params.wpa_ie_len = wpa_s->sme.assoc_req_ie_len;
00310 #ifdef CONFIG_IEEE80211R
00311         if (auth_type == WLAN_AUTH_FT && wpa_s->sme.ft_ies) {
00312                 params.wpa_ie = wpa_s->sme.ft_ies;
00313                 params.wpa_ie_len = wpa_s->sme.ft_ies_len;
00314         }
00315 #endif /* CONFIG_IEEE80211R */
00316         params.mode = mode;
00317         params.mgmt_frame_protection = wpa_s->sme.mfp;
00318         if (wpa_s->sme.prev_bssid_set)
00319                 params.prev_bssid = wpa_s->sme.prev_bssid;
00320 
00321         wpa_msg(wpa_s, MSG_INFO, "Trying to associate with " MACSTR
00322                 " (SSID='%s' freq=%d MHz)", MAC2STR(params.bssid),
00323                 params.ssid ? wpa_ssid_txt(params.ssid, params.ssid_len) : "",
00324                 params.freq);
00325 
00326         wpa_supplicant_set_state(wpa_s, WPA_ASSOCIATING);
00327 
00328         if (params.wpa_ie == NULL ||
00329             ieee802_11_parse_elems(params.wpa_ie, params.wpa_ie_len, &elems, 0)
00330             < 0) {
00331                 wpa_printf(MSG_DEBUG, "SME: Could not parse own IEs?!");
00332                 os_memset(&elems, 0, sizeof(elems));
00333         }
00334         if (elems.rsn_ie)
00335                 wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.rsn_ie - 2,
00336                                         elems.rsn_ie_len + 2);
00337         else if (elems.wpa_ie)
00338                 wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.wpa_ie - 2,
00339                                         elems.wpa_ie_len + 2);
00340         else
00341                 wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, NULL, 0);
00342 
00343         if (wpa_drv_associate(wpa_s, &params) < 0) {
00344                 wpa_msg(wpa_s, MSG_INFO, "Association request to the driver "
00345                         "failed");
00346                 wpa_supplicant_req_scan(wpa_s, 5, 0);
00347                 return;
00348         }
00349 
00350         /* TODO: add timeout on association */
00351 }
00352 
00353 
00354 int sme_update_ft_ies(struct wpa_supplicant *wpa_s, const u8 *md,
00355                       const u8 *ies, size_t ies_len)
00356 {
00357         if (md == NULL || ies == NULL) {
00358                 wpa_printf(MSG_DEBUG, "SME: Remove mobility domain");
00359                 os_free(wpa_s->sme.ft_ies);
00360                 wpa_s->sme.ft_ies = NULL;
00361                 wpa_s->sme.ft_ies_len = 0;
00362                 wpa_s->sme.ft_used = 0;
00363                 return 0;
00364         }
00365 
00366         os_memcpy(wpa_s->sme.mobility_domain, md, MOBILITY_DOMAIN_ID_LEN);
00367         wpa_hexdump(MSG_DEBUG, "SME: FT IEs", ies, ies_len);
00368         os_free(wpa_s->sme.ft_ies);
00369         wpa_s->sme.ft_ies = os_malloc(ies_len);
00370         if (wpa_s->sme.ft_ies == NULL)
00371                 return -1;
00372         os_memcpy(wpa_s->sme.ft_ies, ies, ies_len);
00373         wpa_s->sme.ft_ies_len = ies_len;
00374         return 0;
00375 }
00376 
00377 
00378 void sme_event_assoc_reject(struct wpa_supplicant *wpa_s,
00379                             union wpa_event_data *data)
00380 {
00381         int bssid_changed;
00382         int timeout = 5000;
00383 
00384         wpa_printf(MSG_DEBUG, "SME: Association with " MACSTR " failed: "
00385                    "status code %d", MAC2STR(wpa_s->pending_bssid),
00386                    data->assoc_reject.status_code);
00387 
00388         bssid_changed = !is_zero_ether_addr(wpa_s->bssid);
00389 
00390         /*
00391          * For now, unconditionally terminate the previous authentication. In
00392          * theory, this should not be needed, but mac80211 gets quite confused
00393          * if the authentication is left pending.. Some roaming cases might
00394          * benefit from using the previous authentication, so this could be
00395          * optimized in the future.
00396          */
00397         if (wpa_drv_deauthenticate(wpa_s, wpa_s->pending_bssid,
00398                                    WLAN_REASON_DEAUTH_LEAVING) < 0) {
00399                 wpa_msg(wpa_s, MSG_INFO,
00400                         "Deauth request to the driver failed");
00401         }
00402         wpa_s->sme.prev_bssid_set = 0;
00403 
00404         if (wpa_blacklist_add(wpa_s, wpa_s->pending_bssid) == 0) {
00405                 struct wpa_blacklist *b;
00406                 b = wpa_blacklist_get(wpa_s, wpa_s->pending_bssid);
00407                 if (b && b->count < 3) {
00408                         /*
00409                          * Speed up next attempt if there could be other APs
00410                          * that could accept association.
00411                          */
00412                         timeout = 100;
00413                 }
00414         }
00415         wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
00416         os_memset(wpa_s->bssid, 0, ETH_ALEN);
00417         os_memset(wpa_s->pending_bssid, 0, ETH_ALEN);
00418         if (bssid_changed)
00419                 wpas_notify_bssid_changed(wpa_s);
00420 
00421         /*
00422          * TODO: if more than one possible AP is available in scan results,
00423          * could try the other ones before requesting a new scan.
00424          */
00425         wpa_supplicant_req_scan(wpa_s, timeout / 1000,
00426                                 1000 * (timeout % 1000));
00427 }
00428 
00429 
00430 void sme_event_auth_timed_out(struct wpa_supplicant *wpa_s,
00431                               union wpa_event_data *data)
00432 {
00433         int timeout = 5000;
00434         
00435         wpa_printf(MSG_DEBUG, "SME: Authentication timed out");
00436         
00437         if (wpa_blacklist_add(wpa_s, wpa_s->pending_bssid) == 0) {
00438                 struct wpa_blacklist *b;
00439                 b = wpa_blacklist_get(wpa_s, wpa_s->pending_bssid);
00440                 if (b && b->count < 3) {
00441                         /*
00442                          * Speed up next attempt if there could be other APs
00443                          * that could accept association.
00444                          */
00445                         timeout = 100;
00446                 }
00447         }
00448         wpa_supplicant_req_scan(wpa_s, timeout / 1000,
00449                                 1000 * (timeout % 1000));
00450 }
00451 
00452 
00453 void sme_event_assoc_timed_out(struct wpa_supplicant *wpa_s,
00454                                union wpa_event_data *data)
00455 {
00456         wpa_printf(MSG_DEBUG, "SME: Association timed out");
00457         wpa_supplicant_mark_disassoc(wpa_s);
00458         wpa_supplicant_req_scan(wpa_s, 5, 0);
00459 }
00460 
00461 
00462 void sme_event_disassoc(struct wpa_supplicant *wpa_s,
00463                         union wpa_event_data *data)
00464 {
00465         wpa_printf(MSG_DEBUG, "SME: Disassociation event received");
00466         if (!is_zero_ether_addr(wpa_s->bssid) &&
00467             !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)) {
00468                 /*
00469                  * cfg80211/mac80211 can get into somewhat confused state if
00470                  * the AP only disassociates us and leaves us in authenticated
00471                  * state. For now, force the state to be cleared to avoid
00472                  * confusing errors if we try to associate with the AP again.
00473                  */
00474                 wpa_printf(MSG_DEBUG, "SME: Deauthenticate to clear driver "
00475                            "state");
00476                 wpa_drv_deauthenticate(wpa_s, wpa_s->bssid,
00477                                        WLAN_REASON_DEAUTH_LEAVING);
00478         }
00479 }