[PATCH] mac80211: allow drivers to report (non-)monitor frames

[PATCH] mac80211: allow drivers to report (non-)monitor frames

[Grzegorz Bajorski]

This allows drivers to tell mac80211 whether given
frame is to be processed regularly but skip
monitor interface delivery or vice versa.

Signed-off-by: Grzegorz Bajorski <grzegorz.bajorski@tieto.com>
---
 include/net/mac80211.h | 11 +++++++++++
 net/mac80211/rx.c      |  5 +++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 7c30faf..a35e584 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1014,6 +1014,14 @@ ieee80211_tx_info_clear_status(struct ieee80211_tx_info *info)
  * @RX_FLAG_AMPDU_DELIM_CRC_KNOWN: The delimiter CRC field is known (the CRC
  *	is stored in the @ampdu_delimiter_crc field)
  * @RX_FLAG_LDPC: LDPC was used
+ * @RX_FLAG_ONLY_MONITOR: Report frame only to monitor interfaces without
+ *	processing it in any regular way.
+ *	This is useful if drivers offload some frames but still want to report
+ *	them for sniffing purposes.
+ * @RX_FLAG_SKIP_MONITOR: Process and report frame to all interfaces except
+ *	monitor interfaces.
+ *	This is useful if drivers offload some frames but still want to report
+ *	them for sniffing purposes.
  * @RX_FLAG_STBC_MASK: STBC 2 bit bitmask. 1 - Nss=1, 2 - Nss=2, 3 - Nss=3
  * @RX_FLAG_10MHZ: 10 MHz (half channel) was used
  * @RX_FLAG_5MHZ: 5 MHz (quarter channel) was used
@@ -1054,6 +1062,8 @@ enum mac80211_rx_flags {
 	RX_FLAG_MACTIME_END		= BIT(21),
 	RX_FLAG_VHT			= BIT(22),
 	RX_FLAG_LDPC			= BIT(23),
+	RX_FLAG_ONLY_MONITOR		= BIT(24),
+	RX_FLAG_SKIP_MONITOR		= BIT(25),
 	RX_FLAG_STBC_MASK		= BIT(26) | BIT(27),
 	RX_FLAG_10MHZ			= BIT(28),
 	RX_FLAG_5MHZ			= BIT(29),
@@ -1072,6 +1082,7 @@ enum mac80211_rx_flags {
  * @RX_VHT_FLAG_160MHZ: 160 MHz was used
  * @RX_VHT_FLAG_BF: packet was beamformed
  */
+
 enum mac80211_rx_vht_flags {
 	RX_VHT_FLAG_80MHZ		= BIT(0),
 	RX_VHT_FLAG_160MHZ		= BIT(1),
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 1f82753..43ad7a5 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -122,7 +122,8 @@ static inline bool should_drop_frame(struct sk_buff *skb, int present_fcs_len,
 	hdr = (void *)(skb->data + rtap_vendor_space);
 
 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
-			    RX_FLAG_FAILED_PLCP_CRC))
+			    RX_FLAG_FAILED_PLCP_CRC |
+			    RX_FLAG_ONLY_MONITOR))
 		return true;
 
 	if (unlikely(skb->len < 16 + present_fcs_len + rtap_vendor_space))
@@ -507,7 +508,7 @@ ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 		return NULL;
 	}
 
-	if (!local->monitors) {
+	if (!local->monitors || (status->flag & RX_FLAG_SKIP_MONITOR)) {
 		if (should_drop_frame(origskb, present_fcs_len,
 				      rtap_vendor_space)) {
 			dev_kfree_skb(origskb);
-- 
2.3.7

Re: [PATCH] mac80211: allow drivers to report (non-)monitor frames

[Johannes Berg]

On Mon, 2015-11-30 at 13:54 +0100, Grzegorz Bajorski wrote:
> This allows drivers to tell mac80211 whether given
> frame is to be processed regularly but skip
> monitor interface delivery or vice versa.
> 
Can you give an example, and perhaps a corresponding driver patch?

johannes

Re: [PATCH] mac80211: allow drivers to report (non-)monitor frames

[Grzegorz Bajorski]

already sent in [PATCH] ath10k: deliver mgmt frames from htt to
monitor vifs only.

2015-11-30 14:14 GMT+01:00 Johannes Berg <johannes@sipsolutions.net>:
> On Mon, 2015-11-30 at 13:54 +0100, Grzegorz Bajorski wrote:
>> This allows drivers to tell mac80211 whether given
>> frame is to be processed regularly but skip
>> monitor interface delivery or vice versa.
>>
> Can you give an example, and perhaps a corresponding driver patch?
>
> johannes



-- 
Pozdrawiam / Best Regards
Grzegorz Bajorski

Re: [PATCH] mac80211: allow drivers to report (non-)monitor frames

[Johannes Berg]

On Tue, 2015-12-01 at 09:07 +0100, Grzegorz Bajorski wrote:
> already sent in [PATCH] ath10k: deliver mgmt frames from htt to
> monitor vifs only.
> 

I see. Perhaps you can resend this patch with a bit of a description of
why you'd want that?

johannes

[PATCHv2] mac80211: allow drivers to report (non-)monitor frames

[Grzegorz Bajorski]

Some drivers offload some frames internally (e.g.
AddBa). Reporting such frames to mac80211 would
only confuse MLME. However it would be useful to
be able to pass such frames to monitor interfaces
for sniffing purposes, e.g. when running AP +
monitor.

To do that allow drivers to tell mac80211 whether
a given frame should be:
 - processed but not delivered to any monitor vif
 - not processed but delievered to monitor vifs
   only

Signed-off-by: Grzegorz Bajorski <grzegorz.bajorski@tieto.com>
---

Notes:
    v2:
     * fix commit log [Johannes]

 include/net/mac80211.h | 11 +++++++++++
 net/mac80211/rx.c      |  5 +++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 7c30faf..a35e584 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1014,6 +1014,14 @@ ieee80211_tx_info_clear_status(struct ieee80211_tx_info *info)
  * @RX_FLAG_AMPDU_DELIM_CRC_KNOWN: The delimiter CRC field is known (the CRC
  *	is stored in the @ampdu_delimiter_crc field)
  * @RX_FLAG_LDPC: LDPC was used
+ * @RX_FLAG_ONLY_MONITOR: Report frame only to monitor interfaces without
+ *	processing it in any regular way.
+ *	This is useful if drivers offload some frames but still want to report
+ *	them for sniffing purposes.
+ * @RX_FLAG_SKIP_MONITOR: Process and report frame to all interfaces except
+ *	monitor interfaces.
+ *	This is useful if drivers offload some frames but still want to report
+ *	them for sniffing purposes.
  * @RX_FLAG_STBC_MASK: STBC 2 bit bitmask. 1 - Nss=1, 2 - Nss=2, 3 - Nss=3
  * @RX_FLAG_10MHZ: 10 MHz (half channel) was used
  * @RX_FLAG_5MHZ: 5 MHz (quarter channel) was used
@@ -1054,6 +1062,8 @@ enum mac80211_rx_flags {
 	RX_FLAG_MACTIME_END		= BIT(21),
 	RX_FLAG_VHT			= BIT(22),
 	RX_FLAG_LDPC			= BIT(23),
+	RX_FLAG_ONLY_MONITOR		= BIT(24),
+	RX_FLAG_SKIP_MONITOR		= BIT(25),
 	RX_FLAG_STBC_MASK		= BIT(26) | BIT(27),
 	RX_FLAG_10MHZ			= BIT(28),
 	RX_FLAG_5MHZ			= BIT(29),
@@ -1072,6 +1082,7 @@ enum mac80211_rx_flags {
  * @RX_VHT_FLAG_160MHZ: 160 MHz was used
  * @RX_VHT_FLAG_BF: packet was beamformed
  */
+
 enum mac80211_rx_vht_flags {
 	RX_VHT_FLAG_80MHZ		= BIT(0),
 	RX_VHT_FLAG_160MHZ		= BIT(1),
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 1f82753..43ad7a5 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -122,7 +122,8 @@ static inline bool should_drop_frame(struct sk_buff *skb, int present_fcs_len,
 	hdr = (void *)(skb->data + rtap_vendor_space);
 
 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
-			    RX_FLAG_FAILED_PLCP_CRC))
+			    RX_FLAG_FAILED_PLCP_CRC |
+			    RX_FLAG_ONLY_MONITOR))
 		return true;
 
 	if (unlikely(skb->len < 16 + present_fcs_len + rtap_vendor_space))
@@ -507,7 +508,7 @@ ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 		return NULL;
 	}
 
-	if (!local->monitors) {
+	if (!local->monitors || (status->flag & RX_FLAG_SKIP_MONITOR)) {
 		if (should_drop_frame(origskb, present_fcs_len,
 				      rtap_vendor_space)) {
 			dev_kfree_skb(origskb);
-- 
2.3.7