hostapd/tkip_countermeasures.c

   1 /*
   2  * hostapd / TKIP countermeasures
   3  * Copyright (c) 2002-2009, 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 "hostapd.h"
  19 #include "eloop.h"
  20 #include "driver_i.h"
  21 #include "sta_flags.h"
  22 #include "sta_info.h"
  23 #include "mlme.h"
  24 #include "wpa.h"
  25 #include "common/ieee802_11_defs.h"
  26 #include "tkip_countermeasures.h"
  27
  28
  29 static void ieee80211_tkip_countermeasures_stop(void *eloop_ctx,
  30                                                 void *timeout_ctx)
  31 {
  32         struct hostapd_data *hapd = eloop_ctx;
  33         hapd->tkip_countermeasures = 0;
  34         hostapd_set_countermeasures(hapd, 0);
  35         hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
  36                        HOSTAPD_LEVEL_INFO, "TKIP countermeasures ended");
  37 }
  38
  39
  40 static void ieee80211_tkip_countermeasures_start(struct hostapd_data *hapd)
  41 {
  42         struct sta_info *sta;
  43
  44         hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
  45                        HOSTAPD_LEVEL_INFO, "TKIP countermeasures initiated");
  46
  47         wpa_auth_countermeasures_start(hapd->wpa_auth);
  48         hapd->tkip_countermeasures = 1;
  49         hostapd_set_countermeasures(hapd, 1);
  50         wpa_gtk_rekey(hapd->wpa_auth);
  51         eloop_cancel_timeout(ieee80211_tkip_countermeasures_stop, hapd, NULL);
  52         eloop_register_timeout(60, 0, ieee80211_tkip_countermeasures_stop,
  53                                hapd, NULL);
  54         for (sta = hapd->sta_list; sta != NULL; sta = sta->next) {
  55                 hostapd_sta_deauth(hapd, sta->addr,
  56                                    WLAN_REASON_MICHAEL_MIC_FAILURE);
  57                 sta->flags &= ~(WLAN_STA_AUTH | WLAN_STA_ASSOC |
  58                                 WLAN_STA_AUTHORIZED);
  59                 hostapd_sta_remove(hapd, sta->addr);
  60         }
  61 }
  62
  63
  64 void michael_mic_failure(struct hostapd_data *hapd, const u8 *addr, int local)
  65 {
  66         time_t now;
  67
  68         if (addr && local) {
  69                 struct sta_info *sta = ap_get_sta(hapd, addr);
  70                 if (sta != NULL) {
  71                         wpa_auth_sta_local_mic_failure_report(sta->wpa_sm);
  72                         hostapd_logger(hapd, addr, HOSTAPD_MODULE_IEEE80211,
  73                                        HOSTAPD_LEVEL_INFO,
  74                                        "Michael MIC failure detected in "
  75                                        "received frame");
  76                         mlme_michaelmicfailure_indication(hapd, addr);
  77                 } else {
  78                         wpa_printf(MSG_DEBUG,
  79                                    "MLME-MICHAELMICFAILURE.indication "
  80                                    "for not associated STA (" MACSTR
  81                                    ") ignored", MAC2STR(addr));
  82                         return;
  83                 }
  84         }
  85
  86         time(&now);
  87         if (now > hapd->michael_mic_failure + 60) {
  88                 hapd->michael_mic_failures = 1;
  89         } else {
  90                 hapd->michael_mic_failures++;
  91                 if (hapd->michael_mic_failures > 1)
  92                         ieee80211_tkip_countermeasures_start(hapd);
  93         }
  94         hapd->michael_mic_failure = now;
  95 }