fragattacks/src/drivers/driver_nl80211_event.c

/*
 * Driver interaction with Linux nl80211/cfg80211 - Event processing
 * Copyright (c) 2002-2014, Jouni Malinen <j@w1.fi>
 * Copyright (c) 2007, Johannes Berg <johannes@sipsolutions.net>
 * Copyright (c) 2009-2010, Atheros Communications
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "includes.h"
#include <netlink/genl/genl.h>

#include "utils/common.h"
#include "common/ieee802_11_defs.h"
#include "common/ieee802_11_common.h"
#include "driver_nl80211.h"


static void mlme_event_auth(struct wpa_driver_nl80211_data *drv,
			    const u8 *frame, size_t len)
{
	const struct ieee80211_mgmt *mgmt;
	union wpa_event_data event;

	if (!(drv->capa.flags & WPA_DRIVER_FLAGS_SME) &&
	    drv->force_connect_cmd) {
		/*
		 * Avoid reporting two association events that would confuse
		 * the core code.
		 */
		wpa_printf(MSG_DEBUG,
			   "nl80211: Ignore auth event when using driver SME");
		return;
	}

	wpa_printf(MSG_DEBUG, "nl80211: Authenticate event");
	mgmt = (const struct ieee80211_mgmt *) frame;
	if (len < 24 + sizeof(mgmt->u.auth)) {
		wpa_printf(MSG_DEBUG, "nl80211: Too short association event "
			   "frame");
		return;
	}

	os_memcpy(drv->auth_bssid, mgmt->sa, ETH_ALEN);
	os_memset(drv->auth_attempt_bssid, 0, ETH_ALEN);
	os_memset(&event, 0, sizeof(event));
	os_memcpy(event.auth.peer, mgmt->sa, ETH_ALEN);
	event.auth.auth_type = le_to_host16(mgmt->u.auth.auth_alg);
	event.auth.auth_transaction =
		le_to_host16(mgmt->u.auth.auth_transaction);
	event.auth.status_code = le_to_host16(mgmt->u.auth.status_code);
	if (len > 24 + sizeof(mgmt->u.auth)) {
		event.auth.ies = mgmt->u.auth.variable;
		event.auth.ies_len = len - 24 - sizeof(mgmt->u.auth);
	}

	wpa_supplicant_event(drv->ctx, EVENT_AUTH, &event);
}


static void mlme_event_assoc(struct wpa_driver_nl80211_data *drv,
			    const u8 *frame, size_t len)
{
	const struct ieee80211_mgmt *mgmt;
	union wpa_event_data event;
	u16 status;

	if (!(drv->capa.flags & WPA_DRIVER_FLAGS_SME) &&
	    drv->force_connect_cmd) {
		/*
		 * Avoid reporting two association events that would confuse
		 * the core code.
		 */
		wpa_printf(MSG_DEBUG,
			   "nl80211: Ignore assoc event when using driver SME");
		return;
	}

	wpa_printf(MSG_DEBUG, "nl80211: Associate event");
	mgmt = (const struct ieee80211_mgmt *) frame;
	if (len < 24 + sizeof(mgmt->u.assoc_resp)) {
		wpa_printf(MSG_DEBUG, "nl80211: Too short association event "
			   "frame");
		return;
	}

	status = le_to_host16(mgmt->u.assoc_resp.status_code);
	if (status != WLAN_STATUS_SUCCESS) {
		os_memset(&event, 0, sizeof(event));
		event.assoc_reject.bssid = mgmt->bssid;
		if (len > 24 + sizeof(mgmt->u.assoc_resp)) {
			event.assoc_reject.resp_ies =
				(u8 *) mgmt->u.assoc_resp.variable;
			event.assoc_reject.resp_ies_len =
				len - 24 - sizeof(mgmt->u.assoc_resp);
		}
		event.assoc_reject.status_code = status;

		wpa_supplicant_event(drv->ctx, EVENT_ASSOC_REJECT, &event);
		return;
	}

	drv->associated = 1;
	os_memcpy(drv->bssid, mgmt->sa, ETH_ALEN);
	os_memcpy(drv->prev_bssid, mgmt->sa, ETH_ALEN);

	os_memset(&event, 0, sizeof(event));
	if (len > 24 + sizeof(mgmt->u.assoc_resp)) {
		event.assoc_info.resp_ies = (u8 *) mgmt->u.assoc_resp.variable;
		event.assoc_info.resp_ies_len =
			len - 24 - sizeof(mgmt->u.assoc_resp);
	}

	event.assoc_info.freq = drv->assoc_freq;

	wpa_supplicant_event(drv->ctx, EVENT_ASSOC, &event);
}


void mlme_event_connect(struct wpa_driver_nl80211_data *drv,
			enum nl80211_commands cmd, struct nlattr *status,
			struct nlattr *addr, struct nlattr *req_ie,
			struct nlattr *resp_ie,
			struct nlattr *authorized,
			struct nlattr *key_replay_ctr,
			struct nlattr *ptk_kck,
			struct nlattr *ptk_kek)
{
	union wpa_event_data event;

	if (drv->capa.flags & WPA_DRIVER_FLAGS_SME) {
		/*
		 * Avoid reporting two association events that would confuse
		 * the core code.
		 */
		wpa_printf(MSG_DEBUG, "nl80211: Ignore connect event (cmd=%d) "
			   "when using userspace SME", cmd);
		return;
	}

	if (cmd == NL80211_CMD_CONNECT)
		wpa_printf(MSG_DEBUG, "nl80211: Connect event");
	else if (cmd == NL80211_CMD_ROAM)
		wpa_printf(MSG_DEBUG, "nl80211: Roam event");

	os_memset(&event, 0, sizeof(event));
	if (cmd == NL80211_CMD_CONNECT &&
	    nla_get_u16(status) != WLAN_STATUS_SUCCESS) {
		if (addr)
			event.assoc_reject.bssid = nla_data(addr);
		if (resp_ie) {
			event.assoc_reject.resp_ies = nla_data(resp_ie);
			event.assoc_reject.resp_ies_len = nla_len(resp_ie);
		}
		event.assoc_reject.status_code = nla_get_u16(status);
		wpa_supplicant_event(drv->ctx, EVENT_ASSOC_REJECT, &event);
		return;
	}

	drv->associated = 1;
	if (addr) {
		os_memcpy(drv->bssid, nla_data(addr), ETH_ALEN);
		os_memcpy(drv->prev_bssid, drv->bssid, ETH_ALEN);
	}

	if (req_ie) {
		event.assoc_info.req_ies = nla_data(req_ie);
		event.assoc_info.req_ies_len = nla_len(req_ie);
	}
	if (resp_ie) {
		event.assoc_info.resp_ies = nla_data(resp_ie);
		event.assoc_info.resp_ies_len = nla_len(resp_ie);
	}

	event.assoc_info.freq = nl80211_get_assoc_freq(drv);

	if (authorized && nla_get_u8(authorized)) {
		event.assoc_info.authorized = 1;
		wpa_printf(MSG_DEBUG, "nl80211: connection authorized");
	}
	if (key_replay_ctr) {
		event.assoc_info.key_replay_ctr = nla_data(key_replay_ctr);
		event.assoc_info.key_replay_ctr_len = nla_len(key_replay_ctr);
	}
	if (ptk_kck) {
		event.assoc_info.ptk_kck = nla_data(ptk_kck);
		event.assoc_info.ptk_kck_len = nla_len(ptk_kek);
	}
	if (ptk_kek) {
		event.assoc_info.ptk_kek = nla_data(ptk_kek);
		event.assoc_info.ptk_kek_len = nla_len(ptk_kek);
	}

	wpa_supplicant_event(drv->ctx, EVENT_ASSOC, &event);
}


void mlme_event_disconnect(struct wpa_driver_nl80211_data *drv,
			   struct nlattr *reason, struct nlattr *addr,
			   struct nlattr *by_ap)
{
	union wpa_event_data data;
	unsigned int locally_generated = by_ap == NULL;

	if (drv->capa.flags & WPA_DRIVER_FLAGS_SME) {
		/*
		 * Avoid reporting two disassociation events that could
		 * confuse the core code.
		 */
		wpa_printf(MSG_DEBUG, "nl80211: Ignore disconnect "
			   "event when using userspace SME");
		return;
	}

	if (drv->ignore_next_local_disconnect) {
		drv->ignore_next_local_disconnect = 0;
		if (locally_generated) {
			wpa_printf(MSG_DEBUG, "nl80211: Ignore disconnect "
				   "event triggered during reassociation");
			return;
		}
		wpa_printf(MSG_WARNING, "nl80211: Was expecting local "
			   "disconnect but got another disconnect "
			   "event first");
	}

	wpa_printf(MSG_DEBUG, "nl80211: Disconnect event");
	nl80211_mark_disconnected(drv);
	os_memset(&data, 0, sizeof(data));
	if (reason)
		data.deauth_info.reason_code = nla_get_u16(reason);
	data.deauth_info.locally_generated = by_ap == NULL;
	wpa_supplicant_event(drv->ctx, EVENT_DEAUTH, &data);
}


static int calculate_chan_offset(int width, int freq, int cf1, int cf2)
{
	int freq1 = 0;

	switch (convert2width(width)) {
	case CHAN_WIDTH_20_NOHT:
	case CHAN_WIDTH_20:
		return 0;
	case CHAN_WIDTH_40:
		freq1 = cf1 - 10;
		break;
	case CHAN_WIDTH_80:
		freq1 = cf1 - 30;
		break;
	case CHAN_WIDTH_160:
		freq1 = cf1 - 70;
		break;
	case CHAN_WIDTH_UNKNOWN:
	case CHAN_WIDTH_80P80:
		/* FIXME: implement this */
		return 0;
	}

	return (abs(freq - freq1) / 20) % 2 == 0 ? 1 : -1;
}


void mlme_event_ch_switch(struct wpa_driver_nl80211_data *drv,
			  struct nlattr *ifindex, struct nlattr *freq,
			  struct nlattr *type, struct nlattr *bw,
			  struct nlattr *cf1, struct nlattr *cf2)
{
	struct i802_bss *bss;
	union wpa_event_data data;
	int ht_enabled = 1;
	int chan_offset = 0;
	int ifidx;

	wpa_printf(MSG_DEBUG, "nl80211: Channel switch event");

	if (!freq)
		return;

	ifidx = nla_get_u32(ifindex);
	bss = get_bss_ifindex(drv, ifidx);
	if (bss == NULL) {
		wpa_printf(MSG_WARNING, "nl80211: Unknown ifindex (%d) for channel switch, ignoring",
			   ifidx);
		return;
	}

	if (type) {
		enum nl80211_channel_type ch_type = nla_get_u32(type);

		wpa_printf(MSG_DEBUG, "nl80211: Channel type: %d", ch_type);
		switch (ch_type) {
		case NL80211_CHAN_NO_HT:
			ht_enabled = 0;
			break;
		case NL80211_CHAN_HT20:
			break;
		case NL80211_CHAN_HT40PLUS:
			chan_offset = 1;
			break;
		case NL80211_CHAN_HT40MINUS:
			chan_offset = -1;
			break;
		}
	} else if (bw && cf1) {
		/* This can happen for example with VHT80 ch switch */
		chan_offset = calculate_chan_offset(nla_get_u32(bw),
						    nla_get_u32(freq),
						    nla_get_u32(cf1),
						    cf2 ? nla_get_u32(cf2) : 0);
	} else {
		wpa_printf(MSG_WARNING, "nl80211: Unknown secondary channel information - following channel definition calculations may fail");
	}

	os_memset(&data, 0, sizeof(data));
	data.ch_switch.freq = nla_get_u32(freq);
	data.ch_switch.ht_enabled = ht_enabled;
	data.ch_switch.ch_offset = chan_offset;
	if (bw)
		data.ch_switch.ch_width = convert2width(nla_get_u32(bw));
	if (cf1)
		data.ch_switch.cf1 = nla_get_u32(cf1);
	if (cf2)
		data.ch_switch.cf2 = nla_get_u32(cf2);

	bss->freq = data.ch_switch.freq;

	wpa_supplicant_event(bss->ctx, EVENT_CH_SWITCH, &data);
}


static void mlme_timeout_event(struct wpa_driver_nl80211_data *drv,
			       enum nl80211_commands cmd, struct nlattr *addr)
{
	union wpa_event_data event;
	enum wpa_event_type ev;

	if (nla_len(addr) != ETH_ALEN)
		return;

	wpa_printf(MSG_DEBUG, "nl80211: MLME event %d; timeout with " MACSTR,
		   cmd, MAC2STR((u8 *) nla_data(addr)));

	if (cmd == NL80211_CMD_AUTHENTICATE)
		ev = EVENT_AUTH_TIMED_OUT;
	else if (cmd == NL80211_CMD_ASSOCIATE)
		ev = EVENT_ASSOC_TIMED_OUT;
	else
		return;

	os_memset(&event, 0, sizeof(event));
	os_memcpy(event.timeout_event.addr, nla_data(addr), ETH_ALEN);
	wpa_supplicant_event(drv->ctx, ev, &event);
}


static void mlme_event_mgmt(struct i802_bss *bss,
			    struct nlattr *freq, struct nlattr *sig,
			    const u8 *frame, size_t len)
{
	struct wpa_driver_nl80211_data *drv = bss->drv;
	const struct ieee80211_mgmt *mgmt;
	union wpa_event_data event;
	u16 fc, stype;
	int ssi_signal = 0;
	int rx_freq = 0;

	wpa_printf(MSG_MSGDUMP, "nl80211: Frame event");
	mgmt = (const struct ieee80211_mgmt *) frame;
	if (len < 24) {
		wpa_printf(MSG_DEBUG, "nl80211: Too short management frame");
		return;
	}

	fc = le_to_host16(mgmt->frame_control);
	stype = WLAN_FC_GET_STYPE(fc);

	if (sig)
		ssi_signal = (s32) nla_get_u32(sig);

	os_memset(&event, 0, sizeof(event));
	if (freq) {
		event.rx_mgmt.freq = nla_get_u32(freq);
		rx_freq = drv->last_mgmt_freq = event.rx_mgmt.freq;
	}
	wpa_printf(MSG_DEBUG,
		   "nl80211: RX frame sa=" MACSTR
		   " freq=%d ssi_signal=%d stype=%u (%s) len=%u",
		   MAC2STR(mgmt->sa), rx_freq, ssi_signal, stype, fc2str(fc),
		   (unsigned int) len);
	event.rx_mgmt.frame = frame;
	event.rx_mgmt.frame_len = len;
	event.rx_mgmt.ssi_signal = ssi_signal;
	event.rx_mgmt.drv_priv = bss;
	wpa_supplicant_event(drv->ctx, EVENT_RX_MGMT, &event);
}


static void mlme_event_mgmt_tx_status(struct wpa_driver_nl80211_data *drv,
				      struct nlattr *cookie, const u8 *frame,
				      size_t len, struct nlattr *ack)
{
	union wpa_event_data event;
	const struct ieee80211_hdr *hdr;
	u16 fc;

	wpa_printf(MSG_DEBUG, "nl80211: Frame TX status event");
	if (!is_ap_interface(drv->nlmode)) {
		u64 cookie_val;

		if (!cookie)
			return;

		cookie_val = nla_get_u64(cookie);
		wpa_printf(MSG_DEBUG, "nl80211: Action TX status:"
			   " cookie=0%llx%s (ack=%d)",
			   (long long unsigned int) cookie_val,
			   cookie_val == drv->send_action_cookie ?
			   " (match)" : " (unknown)", ack != NULL);
		if (cookie_val != drv->send_action_cookie)
			return;
	}

	hdr = (const struct ieee80211_hdr *) frame;
	fc = le_to_host16(hdr->frame_control);

	os_memset(&event, 0, sizeof(event));
	event.tx_status.type = WLAN_FC_GET_TYPE(fc);
	event.tx_status.stype = WLAN_FC_GET_STYPE(fc);
	event.tx_status.dst = hdr->addr1;
	event.tx_status.data = frame;
	event.tx_status.data_len = len;
	event.tx_status.ack = ack != NULL;
	wpa_supplicant_event(drv->ctx, EVENT_TX_STATUS, &event);
}


static void mlme_event_deauth_disassoc(struct wpa_driver_nl80211_data *drv,
				       enum wpa_event_type type,
				       const u8 *frame, size_t len)
{
	const struct ieee80211_mgmt *mgmt;
	union wpa_event_data event;
	const u8 *bssid = NULL;
	u16 reason_code = 0;

	if (type == EVENT_DEAUTH)
		wpa_printf(MSG_DEBUG, "nl80211: Deauthenticate event");
	else
		wpa_printf(MSG_DEBUG, "nl80211: Disassociate event");

	mgmt = (const struct ieee80211_mgmt *) frame;
	if (len >= 24) {
		bssid = mgmt->bssid;

		if ((drv->capa.flags & WPA_DRIVER_FLAGS_SME) &&
		    !drv->associated &&
		    os_memcmp(bssid, drv->auth_bssid, ETH_ALEN) != 0 &&
		    os_memcmp(bssid, drv->auth_attempt_bssid, ETH_ALEN) != 0 &&
		    os_memcmp(bssid, drv->prev_bssid, ETH_ALEN) == 0) {
			/*
			 * Avoid issues with some roaming cases where
			 * disconnection event for the old AP may show up after
			 * we have started connection with the new AP.
			 */
			wpa_printf(MSG_DEBUG, "nl80211: Ignore deauth/disassoc event from old AP " MACSTR " when already authenticating with " MACSTR,
				   MAC2STR(bssid),
				   MAC2STR(drv->auth_attempt_bssid));
			return;
		}

		if (drv->associated != 0 &&
		    os_memcmp(bssid, drv->bssid, ETH_ALEN) != 0 &&
		    os_memcmp(bssid, drv->auth_bssid, ETH_ALEN) != 0) {
			/*
			 * We have presumably received this deauth as a
			 * response to a clear_state_mismatch() outgoing
			 * deauth.  Don't let it take us offline!
			 */
			wpa_printf(MSG_DEBUG, "nl80211: Deauth received "
				   "from Unknown BSSID " MACSTR " -- ignoring",
				   MAC2STR(bssid));
			return;
		}
	}

	nl80211_mark_disconnected(drv);
	os_memset(&event, 0, sizeof(event));

	/* Note: Same offset for Reason Code in both frame subtypes */
	if (len >= 24 + sizeof(mgmt->u.deauth))
		reason_code = le_to_host16(mgmt->u.deauth.reason_code);

	if (type == EVENT_DISASSOC) {
		event.disassoc_info.locally_generated =
			!os_memcmp(mgmt->sa, drv->first_bss->addr, ETH_ALEN);
		event.disassoc_info.addr = bssid;
		event.disassoc_info.reason_code = reason_code;
		if (frame + len > mgmt->u.disassoc.variable) {
			event.disassoc_info.ie = mgmt->u.disassoc.variable;
			event.disassoc_info.ie_len = frame + len -
				mgmt->u.disassoc.variable;
		}
	} else {
		if (drv->ignore_deauth_event) {
			wpa_printf(MSG_DEBUG, "nl80211: Ignore deauth event due to previous forced deauth-during-auth");
			drv->ignore_deauth_event = 0;
			return;
		}
		event.deauth_info.locally_generated =
			!os_memcmp(mgmt->sa, drv->first_bss->addr, ETH_ALEN);
		if (drv->ignore_next_local_deauth) {
			drv->ignore_next_local_deauth = 0;
			if (event.deauth_info.locally_generated) {
				wpa_printf(MSG_DEBUG, "nl80211: Ignore deauth event triggered due to own deauth request");
				return;
			}
			wpa_printf(MSG_WARNING, "nl80211: Was expecting local deauth but got another disconnect event first");
		}
		event.deauth_info.addr = bssid;
		event.deauth_info.reason_code = reason_code;
		if (frame + len > mgmt->u.deauth.variable) {
			event.deauth_info.ie = mgmt->u.deauth.variable;
			event.deauth_info.ie_len = frame + len -
				mgmt->u.deauth.variable;
		}
	}

	wpa_supplicant_event(drv->ctx, type, &event);
}


static void mlme_event_unprot_disconnect(struct wpa_driver_nl80211_data *drv,
					 enum wpa_event_type type,
					 const u8 *frame, size_t len)
{
	const struct ieee80211_mgmt *mgmt;
	union wpa_event_data event;
	u16 reason_code = 0;

	if (type == EVENT_UNPROT_DEAUTH)
		wpa_printf(MSG_DEBUG, "nl80211: Unprot Deauthenticate event");
	else
		wpa_printf(MSG_DEBUG, "nl80211: Unprot Disassociate event");

	if (len < 24)
		return;

	mgmt = (const struct ieee80211_mgmt *) frame;

	os_memset(&event, 0, sizeof(event));
	/* Note: Same offset for Reason Code in both frame subtypes */
	if (len >= 24 + sizeof(mgmt->u.deauth))
		reason_code = le_to_host16(mgmt->u.deauth.reason_code);

	if (type == EVENT_UNPROT_DISASSOC) {
		event.unprot_disassoc.sa = mgmt->sa;
		event.unprot_disassoc.da = mgmt->da;
		event.unprot_disassoc.reason_code = reason_code;
	} else {
		event.unprot_deauth.sa = mgmt->sa;
		event.unprot_deauth.da = mgmt->da;
		event.unprot_deauth.reason_code = reason_code;
	}

	wpa_supplicant_event(drv->ctx, type, &event);
}


void mlme_event(struct i802_bss *bss,
		enum nl80211_commands cmd, struct nlattr *frame,
		struct nlattr *addr, struct nlattr *timed_out,
		struct nlattr *freq, struct nlattr *ack,
		struct nlattr *cookie, struct nlattr *sig)
{
	struct wpa_driver_nl80211_data *drv = bss->drv;
	const u8 *data;
	size_t len;

	if (timed_out && addr) {
		mlme_timeout_event(drv, cmd, addr);
		return;
	}

	if (frame == NULL) {
		wpa_printf(MSG_DEBUG,
			   "nl80211: MLME event %d (%s) without frame data",
			   cmd, nl80211_command_to_string(cmd));
		return;
	}

	data = nla_data(frame);
	len = nla_len(frame);
	if (len < 4 + 2 * ETH_ALEN) {
		wpa_printf(MSG_MSGDUMP, "nl80211: MLME event %d (%s) on %s("
			   MACSTR ") - too short",
			   cmd, nl80211_command_to_string(cmd), bss->ifname,
			   MAC2STR(bss->addr));
		return;
	}
	wpa_printf(MSG_MSGDUMP, "nl80211: MLME event %d (%s) on %s(" MACSTR
		   ") A1=" MACSTR " A2=" MACSTR, cmd,
		   nl80211_command_to_string(cmd), bss->ifname,
		   MAC2STR(bss->addr), MAC2STR(data + 4),
		   MAC2STR(data + 4 + ETH_ALEN));
	if (cmd != NL80211_CMD_FRAME_TX_STATUS && !(data[4] & 0x01) &&
	    os_memcmp(bss->addr, data + 4, ETH_ALEN) != 0 &&
	    os_memcmp(bss->addr, data + 4 + ETH_ALEN, ETH_ALEN) != 0) {
		wpa_printf(MSG_MSGDUMP, "nl80211: %s: Ignore MLME frame event "
			   "for foreign address", bss->ifname);
		return;
	}
	wpa_hexdump(MSG_MSGDUMP, "nl80211: MLME event frame",
		    nla_data(frame), nla_len(frame));

	switch (cmd) {
	case NL80211_CMD_AUTHENTICATE:
		mlme_event_auth(drv, nla_data(frame), nla_len(frame));
		break;
	case NL80211_CMD_ASSOCIATE:
		mlme_event_assoc(drv, nla_data(frame), nla_len(frame));
		break;
	case NL80211_CMD_DEAUTHENTICATE:
		mlme_event_deauth_disassoc(drv, EVENT_DEAUTH,
					   nla_data(frame), nla_len(frame));
		break;
	case NL80211_CMD_DISASSOCIATE:
		mlme_event_deauth_disassoc(drv, EVENT_DISASSOC,
					   nla_data(frame), nla_len(frame));
		break;
	case NL80211_CMD_FRAME:
		mlme_event_mgmt(bss, freq, sig, nla_data(frame),
				nla_len(frame));
		break;
	case NL80211_CMD_FRAME_TX_STATUS:
		mlme_event_mgmt_tx_status(drv, cookie, nla_data(frame),
					  nla_len(frame), ack);
		break;
	case NL80211_CMD_UNPROT_DEAUTHENTICATE:
		mlme_event_unprot_disconnect(drv, EVENT_UNPROT_DEAUTH,
					     nla_data(frame), nla_len(frame));
		break;
	case NL80211_CMD_UNPROT_DISASSOCIATE:
		mlme_event_unprot_disconnect(drv, EVENT_UNPROT_DISASSOC,
					     nla_data(frame), nla_len(frame));
		break;
	default:
		break;
	}
}