fragattacks/src/ap/ieee802_11_shared.c

/*
 * hostapd / IEEE 802.11 Management
 * Copyright (c) 2002-2010, Jouni Malinen <j@w1.fi>
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "utils/includes.h"

#include "utils/common.h"
#include "common/ieee802_11_defs.h"
#include "hostapd.h"
#include "sta_info.h"
#include "ap_config.h"
#include "ap_drv_ops.h"
#include "ieee802_11.h"


#ifdef CONFIG_IEEE80211W

u8 * hostapd_eid_assoc_comeback_time(struct hostapd_data *hapd,
				     struct sta_info *sta, u8 *eid)
{
	u8 *pos = eid;
	u32 timeout, tu;
	struct os_time now, passed;

	*pos++ = WLAN_EID_TIMEOUT_INTERVAL;
	*pos++ = 5;
	*pos++ = WLAN_TIMEOUT_ASSOC_COMEBACK;
	os_get_time(&now);
	os_time_sub(&now, &sta->sa_query_start, &passed);
	tu = (passed.sec * 1000000 + passed.usec) / 1024;
	if (hapd->conf->assoc_sa_query_max_timeout > tu)
		timeout = hapd->conf->assoc_sa_query_max_timeout - tu;
	else
		timeout = 0;
	if (timeout < hapd->conf->assoc_sa_query_max_timeout)
		timeout++; /* add some extra time for local timers */
	WPA_PUT_LE32(pos, timeout);
	pos += 4;

	return pos;
}


/* MLME-SAQuery.request */
void ieee802_11_send_sa_query_req(struct hostapd_data *hapd,
				  const u8 *addr, const u8 *trans_id)
{
	struct ieee80211_mgmt mgmt;
	u8 *end;

	wpa_printf(MSG_DEBUG, "IEEE 802.11: Sending SA Query Request to "
		   MACSTR, MAC2STR(addr));
	wpa_hexdump(MSG_DEBUG, "IEEE 802.11: SA Query Transaction ID",
		    trans_id, WLAN_SA_QUERY_TR_ID_LEN);

	os_memset(&mgmt, 0, sizeof(mgmt));
	mgmt.frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
					  WLAN_FC_STYPE_ACTION);
	os_memcpy(mgmt.da, addr, ETH_ALEN);
	os_memcpy(mgmt.sa, hapd->own_addr, ETH_ALEN);
	os_memcpy(mgmt.bssid, hapd->own_addr, ETH_ALEN);
	mgmt.u.action.category = WLAN_ACTION_SA_QUERY;
	mgmt.u.action.u.sa_query_req.action = WLAN_SA_QUERY_REQUEST;
	os_memcpy(mgmt.u.action.u.sa_query_req.trans_id, trans_id,
		  WLAN_SA_QUERY_TR_ID_LEN);
	end = mgmt.u.action.u.sa_query_req.trans_id + WLAN_SA_QUERY_TR_ID_LEN;
	if (hostapd_drv_send_mlme(hapd, &mgmt, end - (u8 *) &mgmt, 0) < 0)
		perror("ieee802_11_send_sa_query_req: send");
}


static void ieee802_11_send_sa_query_resp(struct hostapd_data *hapd,
					  const u8 *sa, const u8 *trans_id)
{
	struct sta_info *sta;
	struct ieee80211_mgmt resp;
	u8 *end;

	wpa_printf(MSG_DEBUG, "IEEE 802.11: Received SA Query Request from "
		   MACSTR, MAC2STR(sa));
	wpa_hexdump(MSG_DEBUG, "IEEE 802.11: SA Query Transaction ID",
		    trans_id, WLAN_SA_QUERY_TR_ID_LEN);

	sta = ap_get_sta(hapd, sa);
	if (sta == NULL || !(sta->flags & WLAN_STA_ASSOC)) {
		wpa_printf(MSG_DEBUG, "IEEE 802.11: Ignore SA Query Request "
			   "from unassociated STA " MACSTR, MAC2STR(sa));
		return;
	}

	wpa_printf(MSG_DEBUG, "IEEE 802.11: Sending SA Query Response to "
		   MACSTR, MAC2STR(sa));

	os_memset(&resp, 0, sizeof(resp));
	resp.frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
					  WLAN_FC_STYPE_ACTION);
	os_memcpy(resp.da, sa, ETH_ALEN);
	os_memcpy(resp.sa, hapd->own_addr, ETH_ALEN);
	os_memcpy(resp.bssid, hapd->own_addr, ETH_ALEN);
	resp.u.action.category = WLAN_ACTION_SA_QUERY;
	resp.u.action.u.sa_query_req.action = WLAN_SA_QUERY_RESPONSE;
	os_memcpy(resp.u.action.u.sa_query_req.trans_id, trans_id,
		  WLAN_SA_QUERY_TR_ID_LEN);
	end = resp.u.action.u.sa_query_req.trans_id + WLAN_SA_QUERY_TR_ID_LEN;
	if (hostapd_drv_send_mlme(hapd, &resp, end - (u8 *) &resp, 0) < 0)
		perror("ieee80211_mgmt_sa_query_request: send");
}


void ieee802_11_sa_query_action(struct hostapd_data *hapd, const u8 *sa,
				const u8 action_type, const u8 *trans_id)
{
	struct sta_info *sta;
	int i;

	if (action_type == WLAN_SA_QUERY_REQUEST) {
		ieee802_11_send_sa_query_resp(hapd, sa, trans_id);
		return;
	}

	if (action_type != WLAN_SA_QUERY_RESPONSE) {
		wpa_printf(MSG_DEBUG, "IEEE 802.11: Unexpected SA Query "
			   "Action %d", action_type);
		return;
	}

	wpa_printf(MSG_DEBUG, "IEEE 802.11: Received SA Query Response from "
		   MACSTR, MAC2STR(sa));
	wpa_hexdump(MSG_DEBUG, "IEEE 802.11: SA Query Transaction ID",
		    trans_id, WLAN_SA_QUERY_TR_ID_LEN);

	/* MLME-SAQuery.confirm */

	sta = ap_get_sta(hapd, sa);
	if (sta == NULL || sta->sa_query_trans_id == NULL) {
		wpa_printf(MSG_DEBUG, "IEEE 802.11: No matching STA with "
			   "pending SA Query request found");
		return;
	}

	for (i = 0; i < sta->sa_query_count; i++) {
		if (os_memcmp(sta->sa_query_trans_id +
			      i * WLAN_SA_QUERY_TR_ID_LEN,
			      trans_id, WLAN_SA_QUERY_TR_ID_LEN) == 0)
			break;
	}

	if (i >= sta->sa_query_count) {
		wpa_printf(MSG_DEBUG, "IEEE 802.11: No matching SA Query "
			   "transaction identifier found");
		return;
	}

	hostapd_logger(hapd, sta->addr, HOSTAPD_MODULE_IEEE80211,
		       HOSTAPD_LEVEL_DEBUG,
		       "Reply to pending SA Query received");
	ap_sta_stop_sa_query(hapd, sta);
}

#endif /* CONFIG_IEEE80211W */


u8 * hostapd_eid_ext_capab(struct hostapd_data *hapd, u8 *eid)
{
	u8 *pos = eid;
	u8 len = 0;

	if (hapd->conf->tdls & (TDLS_PROHIBIT | TDLS_PROHIBIT_CHAN_SWITCH))
		len = 5;
	if (len < 4 && hapd->conf->interworking)
		len = 4;
	if (len == 0)
		return eid;

	*pos++ = WLAN_EID_EXT_CAPAB;
	*pos++ = len;
	*pos++ = 0x00;
	*pos++ = 0x00;
	*pos++ = 0x00;

	*pos = 0x00;
	if (hapd->conf->time_advertisement == 2)
		*pos |= 0x08; /* Bit 27 - UTC TSF Offset */
	if (hapd->conf->interworking)
		*pos |= 0x80; /* Bit 31 - Interworking */
	pos++;

	if (len < 5)
		return pos;
	*pos = 0x00;
	if (hapd->conf->tdls & TDLS_PROHIBIT)
		*pos |= 0x40; /* Bit 38 - TDLS Prohibited */
	if (hapd->conf->tdls & TDLS_PROHIBIT_CHAN_SWITCH)
		*pos |= 0x80; /* Bit 39 - TDLS Channel Switching Prohibited */
	pos++;

	return pos;
}


u8 * hostapd_eid_interworking(struct hostapd_data *hapd, u8 *eid)
{
	u8 *pos = eid;
#ifdef CONFIG_INTERWORKING
	u8 *len;

	if (!hapd->conf->interworking)
		return eid;

	*pos++ = WLAN_EID_INTERWORKING;
	len = pos++;

	*pos = hapd->conf->access_network_type;
	if (hapd->conf->internet)
		*pos |= INTERWORKING_ANO_INTERNET;
	if (hapd->conf->asra)
		*pos |= INTERWORKING_ANO_ASRA;
	if (hapd->conf->esr)
		*pos |= INTERWORKING_ANO_ESR;
	if (hapd->conf->uesa)
		*pos |= INTERWORKING_ANO_UESA;
	pos++;

	if (hapd->conf->venue_info_set) {
		*pos++ = hapd->conf->venue_group;
		*pos++ = hapd->conf->venue_type;
	}

	if (!is_zero_ether_addr(hapd->conf->hessid)) {
		os_memcpy(pos, hapd->conf->hessid, ETH_ALEN);
		pos += ETH_ALEN;
	}

	*len = pos - len - 1;
#endif /* CONFIG_INTERWORKING */

	return pos;
}


u8 * hostapd_eid_adv_proto(struct hostapd_data *hapd, u8 *eid)
{
	u8 *pos = eid;
#ifdef CONFIG_INTERWORKING

	/* TODO: Separate configuration for ANQP? */
	if (!hapd->conf->interworking)
		return eid;

	*pos++ = WLAN_EID_ADV_PROTO;
	*pos++ = 2;
	*pos++ = 0x7F; /* Query Response Length Limit | PAME-BI */
	*pos++ = ACCESS_NETWORK_QUERY_PROTOCOL;
#endif /* CONFIG_INTERWORKING */

	return pos;
}


u8 * hostapd_eid_roaming_consortium(struct hostapd_data *hapd, u8 *eid)
{
	u8 *pos = eid;
#ifdef CONFIG_INTERWORKING
	u8 *len;
	unsigned int i, count;

	if (!hapd->conf->interworking ||
	    hapd->conf->roaming_consortium == NULL ||
	    hapd->conf->roaming_consortium_count == 0)
		return eid;

	*pos++ = WLAN_EID_ROAMING_CONSORTIUM;
	len = pos++;

	/* Number of ANQP OIs (in addition to the max 3 listed here) */
	if (hapd->conf->roaming_consortium_count > 3 + 255)
		*pos++ = 255;
	else if (hapd->conf->roaming_consortium_count > 3)
		*pos++ = hapd->conf->roaming_consortium_count - 3;
	else
		*pos++ = 0;

	/* OU #1 and #2 Lengths */
	*pos = hapd->conf->roaming_consortium[0].len;
	if (hapd->conf->roaming_consortium_count > 1)
		*pos |= hapd->conf->roaming_consortium[1].len << 4;
	pos++;

	if (hapd->conf->roaming_consortium_count > 3)
		count = 3;
	else
		count = hapd->conf->roaming_consortium_count;

	for (i = 0; i < count; i++) {
		os_memcpy(pos, hapd->conf->roaming_consortium[i].oi,
			  hapd->conf->roaming_consortium[i].len);
		pos += hapd->conf->roaming_consortium[i].len;
	}

	*len = pos - len - 1;
#endif /* CONFIG_INTERWORKING */

	return pos;
}


u8 * hostapd_eid_time_adv(struct hostapd_data *hapd, u8 *eid)
{
	if (hapd->conf->time_advertisement != 2)
		return eid;

	if (hapd->time_adv == NULL &&
	    hostapd_update_time_adv(hapd) < 0)
		return eid;

	if (hapd->time_adv == NULL)
		return eid;

	os_memcpy(eid, wpabuf_head(hapd->time_adv),
		  wpabuf_len(hapd->time_adv));
	eid += wpabuf_len(hapd->time_adv);

	return eid;
}


u8 * hostapd_eid_time_zone(struct hostapd_data *hapd, u8 *eid)
{
	size_t len;

	if (hapd->conf->time_advertisement != 2)
		return eid;

	len = os_strlen(hapd->conf->time_zone);

	*eid++ = WLAN_EID_TIME_ZONE;
	*eid++ = len;
	os_memcpy(eid, hapd->conf->time_zone, len);
	eid += len;

	return eid;
}


int hostapd_update_time_adv(struct hostapd_data *hapd)
{
	const int elen = 2 + 1 + 10 + 5 + 1;
	struct os_time t;
	struct os_tm tm;
	u8 *pos;

	if (hapd->conf->time_advertisement != 2)
		return 0;

	if (os_get_time(&t) < 0 || os_gmtime(t.sec, &tm) < 0)
		return -1;

	if (!hapd->time_adv) {
		hapd->time_adv = wpabuf_alloc(elen);
		if (hapd->time_adv == NULL)
			return -1;
		pos = wpabuf_put(hapd->time_adv, elen);
	} else
		pos = wpabuf_mhead_u8(hapd->time_adv);

	*pos++ = WLAN_EID_TIME_ADVERTISEMENT;
	*pos++ = 1 + 10 + 5 + 1;

	*pos++ = 2; /* UTC time at which the TSF timer is 0 */

	/* Time Value at TSF 0 */
	/* FIX: need to calculate this based on the current TSF value */
	WPA_PUT_LE16(pos, tm.year); /* Year */
	pos += 2;
	*pos++ = tm.month; /* Month */
	*pos++ = tm.day; /* Day of month */
	*pos++ = tm.hour; /* Hours */
	*pos++ = tm.min; /* Minutes */
	*pos++ = tm.sec; /* Seconds */
	WPA_PUT_LE16(pos, 0); /* Milliseconds (not used) */
	pos += 2;
	*pos++ = 0; /* Reserved */

	/* Time Error */
	/* TODO: fill in an estimate on the error */
	*pos++ = 0;
	*pos++ = 0;
	*pos++ = 0;
	*pos++ = 0;
	*pos++ = 0;

	*pos++ = hapd->time_update_counter++;

	return 0;
}