src/ap/tkip_countermeasures.c

   1 /*
   2  * hostapd / TKIP countermeasures
   3  * Copyright (c) 2002-2011, 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 "utils/includes.h"
  16
  17 #include "utils/common.h"
  18 #include "utils/eloop.h"
  19 #include "common/ieee802_11_defs.h"
  20 #include "hostapd.h"
  21 #include "sta_info.h"
  22 #include "ap_mlme.h"
  23 #include "wpa_auth.h"
  24 #include "ap_drv_ops.h"
  25 #include "tkip_countermeasures.h"
  26
  27
  28 static void ieee80211_tkip_countermeasures_stop(void *eloop_ctx,
  29                                                 void *timeout_ctx)
  30 {
  31         struct hostapd_data *hapd = eloop_ctx;
  32         hapd->tkip_countermeasures = 0;
  33         hostapd_drv_set_countermeasures(hapd, 0);
  34         hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
  35                        HOSTAPD_LEVEL_INFO, "TKIP countermeasures ended");
  36 }
  37
  38
  39 static void ieee80211_tkip_countermeasures_start(struct hostapd_data *hapd)
  40 {
  41         struct sta_info *sta;
  42
  43         hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
  44                        HOSTAPD_LEVEL_INFO, "TKIP countermeasures initiated");
  45
  46         wpa_auth_countermeasures_start(hapd->wpa_auth);
  47         hapd->tkip_countermeasures = 1;
  48         hostapd_drv_set_countermeasures(hapd, 1);
  49         wpa_gtk_rekey(hapd->wpa_auth);
  50         eloop_cancel_timeout(ieee80211_tkip_countermeasures_stop, hapd, NULL);
  51         eloop_register_timeout(60, 0, ieee80211_tkip_countermeasures_stop,
  52                                hapd, NULL);
  53         for (sta = hapd->sta_list; sta != NULL; sta = sta->next) {
  54                 hostapd_drv_sta_deauth(hapd, sta->addr,
  55                                        WLAN_REASON_MICHAEL_MIC_FAILURE);
  56                 ap_sta_set_authorized(hapd, sta, 0);
  57                 sta->flags &= ~(WLAN_STA_AUTH | WLAN_STA_ASSOC);
  58                 hostapd_drv_sta_remove(hapd, sta->addr);
  59         }
  60 }
  61
  62
  63 void ieee80211_tkip_countermeasures_deinit(struct hostapd_data *hapd)
  64 {
  65         eloop_cancel_timeout(ieee80211_tkip_countermeasures_stop, hapd, NULL);
  66 }
  67
  68
  69 void michael_mic_failure(struct hostapd_data *hapd, const u8 *addr, int local)
  70 {
  71         struct os_time now;
  72
  73         if (addr && local) {
  74                 struct sta_info *sta = ap_get_sta(hapd, addr);
  75                 if (sta != NULL) {
  76                         wpa_auth_sta_local_mic_failure_report(sta->wpa_sm);
  77                         hostapd_logger(hapd, addr, HOSTAPD_MODULE_IEEE80211,
  78                                        HOSTAPD_LEVEL_INFO,
  79                                        "Michael MIC failure detected in "
  80                                        "received frame");
  81                         mlme_michaelmicfailure_indication(hapd, addr);
  82                 } else {
  83                         wpa_printf(MSG_DEBUG,
  84                                    "MLME-MICHAELMICFAILURE.indication "
  85                                    "for not associated STA (" MACSTR
  86                                    ") ignored", MAC2STR(addr));
  87                         return;
  88                 }
  89         }
  90
  91         os_get_time(&now);
  92         if (now.sec > hapd->michael_mic_failure + 60) {
  93                 hapd->michael_mic_failures = 1;
  94         } else {
  95                 hapd->michael_mic_failures++;
  96                 if (hapd->michael_mic_failures > 1)
  97                         ieee80211_tkip_countermeasures_start(hapd);
  98         }
  99         hapd->michael_mic_failure = now.sec;
 100 }