Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b4f286a1 authored by Johannes Berg's avatar Johannes Berg
Browse files

mac80211: support extended channel switch 



Support extended channel switch when the operating
class is one of the global operating classes as
defined in Annex E of 802.11-2012. If it isn't,
disconnect from the AP instead.

Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 1ce3e82b

include/linux/ieee80211.h

+12 −0
Original line number Diff line number Diff line
@@ -672,6 +672,18 @@ struct ieee80211_channel_sw_ie { 
	u8 count;

} __packed;



/**

 * struct ieee80211_ext_chansw_ie

 *

 * This structure represents the "Extended Channel Switch Announcement element"

 */

struct ieee80211_ext_chansw_ie {

	u8 mode;

	u8 new_operating_class;

	u8 new_ch_num;

	u8 count;

} __packed;



/**

 * struct ieee80211_tim

 *

net/mac80211/ieee80211_i.h

+1 −0
Original line number Diff line number Diff line
@@ -1178,6 +1178,7 @@ struct ieee802_11_elems { 
	const u8 *perr;

	const struct ieee80211_rann_ie *rann;

	const struct ieee80211_channel_sw_ie *ch_switch_ie;

	const struct ieee80211_ext_chansw_ie *ext_chansw_ie;

	const u8 *country_elem;

	const u8 *pwr_constr_elem;

	const struct ieee80211_timeout_interval_ie *timeout_int;

net/mac80211/mlme.c

+51 −26
Original line number Diff line number Diff line
@@ -1024,56 +1024,79 @@ static void 
ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,

				 u64 timestamp, struct ieee802_11_elems *elems)

{

	struct ieee80211_local *local = sdata->local;

	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

	struct cfg80211_bss *cbss = ifmgd->associated;

	struct ieee80211_bss *bss;

	struct ieee80211_channel *new_ch;

	int new_freq;

	struct ieee80211_chanctx *chanctx;

	enum ieee80211_band new_band;

	int new_freq;

	u8 new_chan_no;

	u8 count;

	u8 mode;



	ASSERT_MGD_MTX(ifmgd);



	if (!cbss)

		return;



	if (sdata->local->scanning)

	if (local->scanning)

		return;



	/* disregard subsequent announcements if we are already processing */

	if (ifmgd->flags & IEEE80211_STA_CSA_RECEIVED)

		return;



	if (!elems->ch_switch_ie)

	if (elems->ext_chansw_ie) {

		if (!ieee80211_operating_class_to_band(

				elems->ext_chansw_ie->new_operating_class,

				&new_band)) {

			sdata_info(sdata,

				   "cannot understand ECSA IE operating class %d, disconnecting\n",

				   elems->ext_chansw_ie->new_operating_class);

			ieee80211_queue_work(&local->hw,

					     &ifmgd->csa_connection_drop_work);

		}

		new_chan_no = elems->ext_chansw_ie->new_ch_num;

		count = elems->ext_chansw_ie->count;

		mode = elems->ext_chansw_ie->mode;

	} else if (elems->ch_switch_ie) {

		new_band = cbss->channel->band;

		new_chan_no = elems->ch_switch_ie->new_ch_num;

		count = elems->ch_switch_ie->count;

		mode = elems->ch_switch_ie->mode;

	} else {

		/* nothing here we understand */

		return;

	}



	bss = (void *)cbss->priv;



	new_freq = ieee80211_channel_to_frequency(

			elems->ch_switch_ie->new_ch_num,

			cbss->channel->band);

	new_ch = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq);

	new_freq = ieee80211_channel_to_frequency(new_chan_no, new_band);

	new_ch = ieee80211_get_channel(local->hw.wiphy, new_freq);

	if (!new_ch || new_ch->flags & IEEE80211_CHAN_DISABLED) {

		sdata_info(sdata,

			   "AP %pM switches to unsupported channel (%d MHz), disconnecting\n",

			   ifmgd->associated->bssid, new_freq);

		ieee80211_queue_work(&sdata->local->hw,

		ieee80211_queue_work(&local->hw,

				     &ifmgd->csa_connection_drop_work);

		return;

	}



	ifmgd->flags |= IEEE80211_STA_CSA_RECEIVED;



	if (sdata->local->use_chanctx) {

	if (local->use_chanctx) {

		sdata_info(sdata,

			   "not handling channel switch with channel contexts\n");

		ieee80211_queue_work(&sdata->local->hw,

		ieee80211_queue_work(&local->hw,

				     &ifmgd->csa_connection_drop_work);

		return;

	}



	mutex_lock(&sdata->local->chanctx_mtx);

	mutex_lock(&local->chanctx_mtx);

	if (WARN_ON(!rcu_access_pointer(sdata->vif.chanctx_conf))) {

		mutex_unlock(&sdata->local->chanctx_mtx);

		mutex_unlock(&local->chanctx_mtx);

		return;

	}

	chanctx = container_of(rcu_access_pointer(sdata->vif.chanctx_conf),
@@ -1081,40 +1104,39 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata, 
	if (chanctx->refcount > 1) {

		sdata_info(sdata,

			   "channel switch with multiple interfaces on the same channel, disconnecting\n");

		ieee80211_queue_work(&sdata->local->hw,

		ieee80211_queue_work(&local->hw,

				     &ifmgd->csa_connection_drop_work);

		mutex_unlock(&sdata->local->chanctx_mtx);

		mutex_unlock(&local->chanctx_mtx);

		return;

	}

	mutex_unlock(&sdata->local->chanctx_mtx);

	mutex_unlock(&local->chanctx_mtx);



	sdata->local->csa_channel = new_ch;

	local->csa_channel = new_ch;



	if (elems->ch_switch_ie->mode)

		ieee80211_stop_queues_by_reason(&sdata->local->hw,

	if (mode)

		ieee80211_stop_queues_by_reason(&local->hw,

				IEEE80211_MAX_QUEUE_MAP,

				IEEE80211_QUEUE_STOP_REASON_CSA);



	if (sdata->local->ops->channel_switch) {

	if (local->ops->channel_switch) {

		/* use driver's channel switch callback */

		struct ieee80211_channel_switch ch_switch = {

			.timestamp = timestamp,

			.block_tx = elems->ch_switch_ie->mode,

			.block_tx = mode,

			.channel = new_ch,

			.count = elems->ch_switch_ie->count,

			.count = count,

		};



		drv_channel_switch(sdata->local, &ch_switch);

		drv_channel_switch(local, &ch_switch);

		return;

	}



	/* channel switch handled in software */

	if (elems->ch_switch_ie->count <= 1)

		ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);

	if (count <= 1)

		ieee80211_queue_work(&local->hw, &ifmgd->chswitch_work);

	else

		mod_timer(&ifmgd->chswitch_timer,

			  TU_TO_EXP_TIME(elems->ch_switch_ie->count *

					 cbss->beacon_interval));

			  TU_TO_EXP_TIME(count * cbss->beacon_interval));

}



static u32 ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
@@ -2629,6 +2651,8 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 
	struct ieee80211_channel *channel;

	bool need_ps = false;



	lockdep_assert_held(&sdata->u.mgd.mtx);



	if ((sdata->u.mgd.associated &&

	     ether_addr_equal(mgmt->bssid, sdata->u.mgd.associated->bssid)) ||

	    (sdata->u.mgd.assoc_data &&
@@ -2670,6 +2694,7 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 
	}



	ieee80211_sta_process_chanswitch(sdata, rx_status->mactime, elems);



}

net/mac80211/util.c

+7 −0
Original line number Diff line number Diff line
@@ -863,6 +863,13 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, 
			}

			elems->ch_switch_ie = (void *)pos;

			break;

		case WLAN_EID_EXT_CHANSWITCH_ANN:

			if (elen != sizeof(struct ieee80211_ext_chansw_ie)) {

				elem_parse_failed = true;

				break;

			}

			elems->ext_chansw_ie = (void *)pos;

			break;

		case WLAN_EID_COUNTRY:

			elems->country_elem = pos;

			elems->country_elem_len = elen;