[PATCH v2] rt2x00: Fix MMIC Countermeasures.

[PATCH v2] rt2x00: Fix MMIC Countermeasures.

[Michael Skeffingfon]

From: Michael Skeffington <mike@astro.ai>

Set RX_FLAG_DECRYPTED in case of MMIC failure so that ieee80211_rx_h_decrypt() doesnt drop the frame before getting to ieee80211_rx_h_michael_mic_verify().

Signed-off-by: Michael Skeffington <mike@astro.ai>

---
 drivers/net/wireless/ralink/rt2x00/rt2800mmio.c | 13 +++++++++++--
 drivers/net/wireless/ralink/rt2x00/rt2800usb.c  | 15 ++++++++++++---
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800mmio.c b/drivers/net/wireless/ralink/rt2x00/rt2800mmio.c
index ee5276e233fa..ace91a2db756 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2800mmio.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800mmio.c
@@ -136,10 +136,19 @@ void rt2800mmio_fill_rxdone(struct queue_entry *entry,
 		 */
 		rxdesc->flags |= RX_FLAG_MMIC_STRIPPED;
 
-		if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS)
+		if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS) {
 			rxdesc->flags |= RX_FLAG_DECRYPTED;
-		else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC)
+        } else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC) {
+			/*
+			 * In order to check the Michael Mic, the packet must have
+			 * been decrypted.  Mac80211 doesnt check the MMIC failure 
+			 * flag to initiate MMIC countermeasures if the decoded flag
+			 * has not been set.
+			 */
+			rxdesc->flags |= RX_FLAG_DECRYPTED;
+
 			rxdesc->flags |= RX_FLAG_MMIC_ERROR;
+        }
 	}
 
 	if (rt2x00_get_field32(word, RXD_W3_MY_BSS))
diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800usb.c b/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
index 685b8e0cd67d..7e5f397c37f9 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
@@ -697,11 +697,20 @@ static void rt2800usb_fill_rxdone(struct queue_entry *entry,
 		 * stripped it from the frame. Signal this to mac80211.
 		 */
 		rxdesc->flags |= RX_FLAG_MMIC_STRIPPED;
-
-		if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS)
+        
+		if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS) {
+			rxdesc->flags |= RX_FLAG_DECRYPTED;
+        } else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC) {
+			/*
+			 * In order to check the Michael Mic, the packet must have
+			 * been decrypted.  Mac80211 doesnt check the MMIC failure 
+			 * flag to initiate MMIC countermeasures if the decoded flag
+			 * has not been set.
+			 */
 			rxdesc->flags |= RX_FLAG_DECRYPTED;
-		else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC)
+
 			rxdesc->flags |= RX_FLAG_MMIC_ERROR;
+        }
 	}
 
 	if (rt2x00_get_field32(word, RXD_W0_MY_BSS))
-- 
2.11.0

Re: [PATCH v2] rt2x00: Fix MMIC Countermeasures.

[Kalle Valo]

Michael Skeffingfon <mike@astro.ai> writes:

> From: Michael Skeffington <mike@astro.ai>
>
> Set RX_FLAG_DECRYPTED in case of MMIC failure so that ieee80211_rx_h_decrypt() doesnt drop the frame before getting to ieee80211_rx_h_michael_mic_verify().
>
> Signed-off-by: Michael Skeffington <mike@astro.ai>

The commit log is not wrapped to 72 characters per line and the period
is not preferred in the title. But I can fix those.


-- 
Kalle Valo

Re: [PATCH v2] rt2x00: Fix MMIC Countermeasures.

[Stanislaw Gruszka]

On Thu, Aug 03, 2017 at 11:31:21AM -0400, Michael Skeffingfon wrote:
> @@ -136,10 +136,19 @@ void rt2800mmio_fill_rxdone(struct queue_entry *entry,
>  		 */
>  		rxdesc->flags |= RX_FLAG_MMIC_STRIPPED;
>  
> -		if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS)
> +		if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS) {
>  			rxdesc->flags |= RX_FLAG_DECRYPTED;
> -		else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC)
> +        } else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC) {

Not sure why this happened, but here and on some other places below,
tab was replaced by spaces resulting in wrong indent.

Stanislaw

Re: [PATCH v2] rt2x00: Fix MMIC Countermeasures.

[Michael Skeffington]

Sorry about that, I work on other projects that use spaces and I must have
missed that when double checking the patch.  I sent out a new patch with
the correct line length, removal of trailing '.' and indentation fix.

On Mon, Aug 7, 2017 at 2:31 AM, Stanislaw Gruszka <sgruszka@redhat.com> wrote:
> On Thu, Aug 03, 2017 at 11:31:21AM -0400, Michael Skeffingfon wrote:
>> @@ -136,10 +136,19 @@ void rt2800mmio_fill_rxdone(struct queue_entry *entry,
>>                */
>>               rxdesc->flags |= RX_FLAG_MMIC_STRIPPED;
>>
>> -             if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS)
>> +             if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS) {
>>                       rxdesc->flags |= RX_FLAG_DECRYPTED;
>> -             else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC)
>> +        } else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC) {
>
> Not sure why this happened, but here and on some other places below,
> tab was replaced by spaces resulting in wrong indent.
>
> Stanislaw