Commit 09a740ce authored by Thomas Pedersen's avatar Thomas Pedersen Committed by Johannes Berg
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mac80211: receive and process S1G beacons 



S1G beacons are 802.11 Extension Frames, so the fixed
header part differs from regular beacons.

Add a handler to process S1G beacons and abstract out the
fetching of BSSID and element start locations in the
beacon body handler.

Signed-off-by: default avatarThomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200922022818.15855-14-thomas@adapt-ip.com


[don't rename, small coding style cleanups]
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent cac8c526

net/mac80211/ieee80211_i.h

+4 −0
Original line number Diff line number Diff line
@@ -1656,6 +1656,8 @@ int ieee80211_set_arp_filter(struct ieee80211_sub_if_data *sdata); 
void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata);

void ieee80211_sta_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,

				  struct sk_buff *skb);

void ieee80211_sta_rx_queued_ext(struct ieee80211_sub_if_data *sdata,

				 struct sk_buff *skb);

void ieee80211_sta_reset_beacon_monitor(struct ieee80211_sub_if_data *sdata);

void ieee80211_sta_reset_conn_monitor(struct ieee80211_sub_if_data *sdata);

void ieee80211_mgd_stop(struct ieee80211_sub_if_data *sdata);
@@ -2301,6 +2303,8 @@ void ieee80211_tdls_handle_disconnect(struct ieee80211_sub_if_data *sdata, 
				      const u8 *peer, u16 reason);

const char *ieee80211_get_reason_code_string(u16 reason_code);

u16 ieee80211_encode_usf(int val);

u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,

			enum nl80211_iftype type);



extern const struct ethtool_ops ieee80211_ethtool_ops;

net/mac80211/iface.c

+5 −0
Original line number Diff line number Diff line
@@ -1433,6 +1433,11 @@ static void ieee80211_iface_work(struct work_struct *work) 
				WARN_ON(1);

				break;

			}

		} else if (ieee80211_is_ext(mgmt->frame_control)) {

			if (sdata->vif.type == NL80211_IFTYPE_STATION)

				ieee80211_sta_rx_queued_ext(sdata, skb);

			else

				WARN_ON(1);

		} else if (ieee80211_is_data_qos(mgmt->frame_control)) {

			struct ieee80211_hdr *hdr = (void *)mgmt;

			/*

net/mac80211/mlme.c

+62 −17
Original line number Diff line number Diff line
@@ -1602,6 +1602,9 @@ static u32 ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata, 
	int new_ap_level;

	__le16 capab = mgmt->u.probe_resp.capab_info;



	if (ieee80211_is_s1g_beacon(mgmt->frame_control))

		return 0;	/* TODO */



	if (country_ie &&

	    (capab & cpu_to_le16(WLAN_CAPABILITY_SPECTRUM_MGMT) ||

	     capab & cpu_to_le16(WLAN_CAPABILITY_RADIO_MEASURE))) {
@@ -3896,11 +3899,12 @@ static bool ieee80211_rx_our_beacon(const u8 *tx_bssid, 
}



static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,

				     struct ieee80211_mgmt *mgmt, size_t len,

				     struct ieee80211_hdr *hdr, size_t len,

				     struct ieee80211_rx_status *rx_status)

{

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

	struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;

	struct ieee80211_mgmt *mgmt = (void *) hdr;

	size_t baselen;

	struct ieee802_11_elems elems;

	struct ieee80211_local *local = sdata->local;
@@ -3910,14 +3914,24 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
	u32 changed = 0;

	bool erp_valid;

	u8 erp_value = 0;

	u32 ncrc;

	u8 *bssid;

	u32 ncrc = 0;

	u8 *bssid, *variable = mgmt->u.beacon.variable;

	u8 deauth_buf[IEEE80211_DEAUTH_FRAME_LEN];



	sdata_assert_lock(sdata);



	/* Process beacon from the current BSS */

	baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;

	bssid = ieee80211_get_bssid(hdr, len, sdata->vif.type);

	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {

		struct ieee80211_ext *ext = (void *) mgmt;



		if (ieee80211_is_s1g_short_beacon(ext->frame_control))

			variable = ext->u.s1g_short_beacon.variable;

		else

			variable = ext->u.s1g_beacon.variable;

	}



	baselen = (u8 *) variable - (u8 *) mgmt;

	if (baselen > len)

		return;
@@ -3937,10 +3951,10 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
	rcu_read_unlock();



	if (ifmgd->assoc_data && ifmgd->assoc_data->need_beacon &&

	    ieee80211_rx_our_beacon(mgmt->bssid, ifmgd->assoc_data->bss)) {

		ieee802_11_parse_elems(mgmt->u.beacon.variable,

	    ieee80211_rx_our_beacon(bssid, ifmgd->assoc_data->bss)) {

		ieee802_11_parse_elems(variable,

				       len - baselen, false, &elems,

				       mgmt->bssid,

				       bssid,

				       ifmgd->assoc_data->bss->bssid);



		ieee80211_rx_bss_info(sdata, mgmt, len, rx_status);
@@ -3973,7 +3987,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
	}



	if (!ifmgd->associated ||

	    !ieee80211_rx_our_beacon(mgmt->bssid,  ifmgd->associated))

	    !ieee80211_rx_our_beacon(bssid,  ifmgd->associated))

		return;

	bssid = ifmgd->associated->bssid;
@@ -3993,8 +4007,14 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
	 */

	ieee80211_sta_reset_beacon_monitor(sdata);



	/* TODO: CRC urrently not calculated on S1G Beacon Compatibility

	 * element (which carries the beacon interval). Don't forget to add a

	 * bit to care_about_ies[] above if mac80211 is interested in a

	 * changing S1G element.

	 */

	if (!ieee80211_is_s1g_beacon(hdr->frame_control))

		ncrc = crc32_be(0, (void *)&mgmt->u.beacon.beacon_int, 4);

	ncrc = ieee802_11_parse_elems_crc(mgmt->u.beacon.variable,

	ncrc = ieee802_11_parse_elems_crc(variable,

					  len - baselen, false, &elems,

					  care_about_ies, ncrc,

					  mgmt->bssid, bssid);
@@ -4028,7 +4048,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
		struct ieee80211_p2p_noa_attr noa = {};

		int ret;



		ret = cfg80211_get_p2p_attr(mgmt->u.beacon.variable,

		ret = cfg80211_get_p2p_attr(variable,

					    len - baselen,

					    IEEE80211_P2P_ATTR_ABSENCE_NOTICE,

					    (u8 *) &noa, sizeof(noa));
@@ -4064,7 +4084,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
	 * the driver will use them. The synchronized view is currently

	 * guaranteed only in certain callbacks.

	 */

	if (ieee80211_hw_check(&local->hw, TIMING_BEACON_ONLY)) {

	if (ieee80211_hw_check(&local->hw, TIMING_BEACON_ONLY) &&

	    !ieee80211_is_s1g_beacon(hdr->frame_control)) {

		sdata->vif.bss_conf.sync_tsf =

			le64_to_cpu(mgmt->u.beacon.timestamp);

		sdata->vif.bss_conf.sync_device_ts =
@@ -4072,7 +4093,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
		sdata->vif.bss_conf.sync_dtim_count = elems.dtim_count;

	}



	if (ncrc == ifmgd->beacon_crc && ifmgd->beacon_crc_valid)

	if ((ncrc == ifmgd->beacon_crc && ifmgd->beacon_crc_valid) ||

	    ieee80211_is_s1g_short_beacon(mgmt->frame_control))

		return;

	ifmgd->beacon_crc = ncrc;

	ifmgd->beacon_crc_valid = true;
@@ -4113,6 +4135,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
	} else {

		erp_valid = false;

	}



	if (!ieee80211_is_s1g_beacon(hdr->frame_control))

		changed |= ieee80211_handle_bss_capability(sdata,

				le16_to_cpu(mgmt->u.beacon.capab_info),

				erp_valid, erp_value);
@@ -4153,6 +4177,26 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 
	ieee80211_bss_info_change_notify(sdata, changed);

}



void ieee80211_sta_rx_queued_ext(struct ieee80211_sub_if_data *sdata,

				 struct sk_buff *skb)

{

	struct ieee80211_rx_status *rx_status;

	struct ieee80211_hdr *hdr;

	u16 fc;



	rx_status = (struct ieee80211_rx_status *) skb->cb;

	hdr = (struct ieee80211_hdr *) skb->data;

	fc = le16_to_cpu(hdr->frame_control);



	sdata_lock(sdata);

	switch (fc & IEEE80211_FCTL_STYPE) {

	case IEEE80211_STYPE_S1G_BEACON:

		ieee80211_rx_mgmt_beacon(sdata, hdr, skb->len, rx_status);

		break;

	}

	sdata_unlock(sdata);

}



void ieee80211_sta_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,

				  struct sk_buff *skb)

{
@@ -4170,7 +4214,8 @@ void ieee80211_sta_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 


	switch (fc & IEEE80211_FCTL_STYPE) {

	case IEEE80211_STYPE_BEACON:

		ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, rx_status);

		ieee80211_rx_mgmt_beacon(sdata, (void *)mgmt,

					 skb->len, rx_status);

		break;

	case IEEE80211_STYPE_PROBE_RESP:

		ieee80211_rx_mgmt_probe_resp(sdata, skb);

net/mac80211/rx.c

+36 −48
Original line number Diff line number Diff line
@@ -42,51 +42,6 @@ static inline void ieee80211_rx_stats(struct net_device *dev, u32 len) 
	u64_stats_update_end(&tstats->syncp);

}



static u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,

			       enum nl80211_iftype type)

{

	__le16 fc = hdr->frame_control;



	if (ieee80211_is_data(fc)) {

		if (len < 24) /* drop incorrect hdr len (data) */

			return NULL;



		if (ieee80211_has_a4(fc))

			return NULL;

		if (ieee80211_has_tods(fc))

			return hdr->addr1;

		if (ieee80211_has_fromds(fc))

			return hdr->addr2;



		return hdr->addr3;

	}



	if (ieee80211_is_mgmt(fc)) {

		if (len < 24) /* drop incorrect hdr len (mgmt) */

			return NULL;

		return hdr->addr3;

	}



	if (ieee80211_is_ctl(fc)) {

		if (ieee80211_is_pspoll(fc))

			return hdr->addr1;



		if (ieee80211_is_back_req(fc)) {

			switch (type) {

			case NL80211_IFTYPE_STATION:

				return hdr->addr2;

			case NL80211_IFTYPE_AP:

			case NL80211_IFTYPE_AP_VLAN:

				return hdr->addr1;

			default:

				break; /* fall through to the return */

			}

		}

	}



	return NULL;

}



/*

 * monitor mode reception

 *
@@ -1802,7 +1757,8 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 
		}

	} else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {

		sta->rx_stats.last_rx = jiffies;

	} else if (!is_multicast_ether_addr(hdr->addr1)) {

	} else if (!ieee80211_is_s1g_beacon(hdr->frame_control) &&

		   is_multicast_ether_addr(hdr->addr1)) {

		/*

		 * Mesh beacons will update last_rx when if they are found to

		 * match the current local configuration when processed.
@@ -1837,6 +1793,9 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 
		}

	}



	if (ieee80211_is_s1g_beacon(hdr->frame_control))

		return RX_CONTINUE;



	/*

	 * Change STA power saving mode only at the end of a frame

	 * exchange sequence, and only for a data or management
@@ -1947,6 +1906,9 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 
	__le16 fc;

	const struct ieee80211_cipher_scheme *cs = NULL;



	if (ieee80211_is_ext(hdr->frame_control))

		return RX_CONTINUE;



	/*

	 * Key selection 101

	 *
@@ -2255,7 +2217,7 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 
	hdr = (struct ieee80211_hdr *)rx->skb->data;

	fc = hdr->frame_control;



	if (ieee80211_is_ctl(fc))

	if (ieee80211_is_ctl(fc) || ieee80211_is_ext(fc))

		return RX_CONTINUE;



	sc = le16_to_cpu(hdr->seq_ctrl);
@@ -3129,6 +3091,9 @@ ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx) 
	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;

	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);



	if (ieee80211_is_s1g_beacon(mgmt->frame_control))

		return RX_CONTINUE;



	/*

	 * From here on, look only at management frames.

	 * Data and control frames are already handled,
@@ -3595,6 +3560,27 @@ ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx) 
	return RX_QUEUED;

}



static ieee80211_rx_result debug_noinline

ieee80211_rx_h_ext(struct ieee80211_rx_data *rx)

{

	struct ieee80211_sub_if_data *sdata = rx->sdata;

	struct ieee80211_hdr *hdr = (void *)rx->skb->data;



	if (!ieee80211_is_ext(hdr->frame_control))

		return RX_CONTINUE;



	if (sdata->vif.type != NL80211_IFTYPE_STATION)

		return RX_DROP_MONITOR;



	/* for now only beacons are ext, so queue them */

	skb_queue_tail(&sdata->skb_queue, rx->skb);

	ieee80211_queue_work(&rx->local->hw, &sdata->work);

	if (rx->sta)

		rx->sta->rx_stats.packets++;



	return RX_QUEUED;

}



static ieee80211_rx_result debug_noinline

ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)

{
@@ -3814,6 +3800,7 @@ static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx, 
		CALL_RXH(ieee80211_rx_h_userspace_mgmt);

		CALL_RXH(ieee80211_rx_h_action_post_userspace);

		CALL_RXH(ieee80211_rx_h_action_return);

		CALL_RXH(ieee80211_rx_h_ext);

		CALL_RXH(ieee80211_rx_h_mgmt);



 rxh_next:
@@ -3980,7 +3967,8 @@ static bool ieee80211_accept_frame(struct ieee80211_rx_data *rx) 
	struct ieee80211_hdr *hdr = (void *)skb->data;

	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);

	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);

	bool multicast = is_multicast_ether_addr(hdr->addr1);

	bool multicast = is_multicast_ether_addr(hdr->addr1) ||

			 ieee80211_is_s1g_beacon(hdr->frame_control);



	switch (sdata->vif.type) {

	case NL80211_IFTYPE_STATION:

net/mac80211/util.c

+52 −0
Original line number Diff line number Diff line
@@ -45,6 +45,58 @@ struct ieee80211_hw *wiphy_to_ieee80211_hw(struct wiphy *wiphy) 
}

EXPORT_SYMBOL(wiphy_to_ieee80211_hw);



u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,

			enum nl80211_iftype type)

{

	__le16 fc = hdr->frame_control;



	if (ieee80211_is_data(fc)) {

		if (len < 24) /* drop incorrect hdr len (data) */

			return NULL;



		if (ieee80211_has_a4(fc))

			return NULL;

		if (ieee80211_has_tods(fc))

			return hdr->addr1;

		if (ieee80211_has_fromds(fc))

			return hdr->addr2;



		return hdr->addr3;

	}



	if (ieee80211_is_s1g_beacon(fc)) {

		struct ieee80211_ext *ext = (void *) hdr;



		return ext->u.s1g_beacon.sa;

	}



	if (ieee80211_is_mgmt(fc)) {

		if (len < 24) /* drop incorrect hdr len (mgmt) */

			return NULL;

		return hdr->addr3;

	}



	if (ieee80211_is_ctl(fc)) {

		if (ieee80211_is_pspoll(fc))

			return hdr->addr1;



		if (ieee80211_is_back_req(fc)) {

			switch (type) {

			case NL80211_IFTYPE_STATION:

				return hdr->addr2;

			case NL80211_IFTYPE_AP:

			case NL80211_IFTYPE_AP_VLAN:

				return hdr->addr1;

			default:

				break; /* fall through to the return */

			}

		}

	}



	return NULL;

}

EXPORT_SYMBOL(ieee80211_get_bssid);



void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx)

{

	struct sk_buff *skb;

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