tkip_countermeasures.c revision 8d520ff1dc2da35cdca849e982051b86468016d8 
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 "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
28static 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
39static 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
63void michael_mic_failure(struct hostapd_data *hapd, const u8 *addr, int local)
64{
65	time_t now;
66
67	if (addr && local) {
68		struct sta_info *sta = ap_get_sta(hapd, addr);
69		if (sta != NULL) {
70			wpa_auth_sta_local_mic_failure_report(sta->wpa_sm);
71			hostapd_logger(hapd, addr, HOSTAPD_MODULE_IEEE80211,
72				       HOSTAPD_LEVEL_INFO,
73				       "Michael MIC failure detected in "
74				       "received frame");
75			mlme_michaelmicfailure_indication(hapd, addr);
76		} else {
77			wpa_printf(MSG_DEBUG,
78				   "MLME-MICHAELMICFAILURE.indication "
79				   "for not associated STA (" MACSTR
80				   ") ignored", MAC2STR(addr));
81			return;
82		}
83	}
84
85	time(&now);
86	if (now > hapd->michael_mic_failure + 60) {
87		hapd->michael_mic_failures = 1;
88	} else {
89		hapd->michael_mic_failures++;
90		if (hapd->michael_mic_failures > 1)
91			ieee80211_tkip_countermeasures_start(hapd);
92	}
93	hapd->michael_mic_failure = now;
94}
95