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