Commit a8241310 authored by Karl Beldan's avatar Karl Beldan Committed by Johannes Berg
Browse files

mac80211: report some VHT radiotap infos for tx status 



The radiotap VHT info is 12 bytes (required to be aligned on 2) :
u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_*
u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_*
u8 bandwidth
u8 mcs_nss[4]
u8 coding
u8 group_id
u16 partial_aid

ATM mac80211 can handle IEEE80211_RADIOTAP_VHT_KNOWN_{GI,BANDWIDTH} and
mcs_nss[0] (i.e single user) in simple cases.
This is more a placeholder to let sniffers give more clues for VHT,
since we don't have yet the proper infrastructure/conventions
in mac80211 for complete feedback (e.g consider dynamic BW).

Signed-off-by: default avatarKarl Beldan <karl.beldan@rivierawaves.com>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 9e2bc79b

net/mac80211/status.c

+63 −13
Original line number Diff line number Diff line
@@ -235,7 +235,8 @@ static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info) 


	/* IEEE80211_RADIOTAP_RATE rate */

	if (info->status.rates[0].idx >= 0 &&

	    !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS))

	    !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |

					     IEEE80211_TX_RC_VHT_MCS)))

		len += 2;



	/* IEEE80211_RADIOTAP_TX_FLAGS */
@@ -244,16 +245,21 @@ static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info) 
	/* IEEE80211_RADIOTAP_DATA_RETRIES */

	len += 1;



	/* IEEE80211_TX_RC_MCS */

	if (info->status.rates[0].idx >= 0 &&

	    info->status.rates[0].flags & IEEE80211_TX_RC_MCS)

	/* IEEE80211_RADIOTAP_MCS

	 * IEEE80211_RADIOTAP_VHT */

	if (info->status.rates[0].idx >= 0) {

		if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)

			len += 3;

		else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)

			len = ALIGN(len, 2) + 12;

	}



	return len;

}



static void

ieee80211_add_tx_radiotap_header(struct ieee80211_supported_band *sband,

ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,

				 struct ieee80211_supported_band *sband,

				 struct sk_buff *skb, int retry_count,

				 int rtap_len, int shift)

{
@@ -280,7 +286,8 @@ ieee80211_add_tx_radiotap_header(struct ieee80211_supported_band *sband, 


	/* IEEE80211_RADIOTAP_RATE */

	if (info->status.rates[0].idx >= 0 &&

	    !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) {

	    !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |

					     IEEE80211_TX_RC_VHT_MCS))) {

		u16 rate;



		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
@@ -310,9 +317,12 @@ ieee80211_add_tx_radiotap_header(struct ieee80211_supported_band *sband, 
	*pos = retry_count;

	pos++;



	/* IEEE80211_TX_RC_MCS */

	if (info->status.rates[0].idx >= 0 &&

	    info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {

	if (info->status.rates[0].idx < 0)

		return;



	/* IEEE80211_RADIOTAP_MCS

	 * IEEE80211_RADIOTAP_VHT */

	if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {

		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);

		pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |

			 IEEE80211_RADIOTAP_MCS_HAVE_GI |
@@ -325,8 +335,48 @@ ieee80211_add_tx_radiotap_header(struct ieee80211_supported_band *sband, 
			pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;

		pos[2] = info->status.rates[0].idx;

		pos += 3;

	}

	} else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {

		u16 known = local->hw.radiotap_vht_details &

			(IEEE80211_RADIOTAP_VHT_KNOWN_GI |

			 IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);



		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);



		/* required alignment from rthdr */

		pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);



		/* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */

		put_unaligned_le16(known, pos);

		pos += 2;



		/* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */

		if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)

			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;

		pos++;



		/* u8 bandwidth */

		if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)

			*pos = 1;

		else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)

			*pos = 4;

		else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)

			*pos = 11;

		else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */

			*pos = 0;

		pos++;



		/* u8 mcs_nss[4] */

		*pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |

			ieee80211_rate_get_vht_nss(&info->status.rates[0]);

		pos += 4;



		/* u8 coding */

		pos++;

		/* u8 group_id */

		pos++;

		/* u16 partial_aid */

		pos += 2;

	}

}



static void ieee80211_report_used_skb(struct ieee80211_local *local,
@@ -631,8 +681,8 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb) 
		dev_kfree_skb(skb);

		return;

	}

	ieee80211_add_tx_radiotap_header(sband, skb, retry_count, rtap_len,

					 shift);

	ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,

					 rtap_len, shift);



	/* XXX: is this sufficient for BPF? */

	skb_set_mac_header(skb, 0);

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