2017-08-03 15:31:50

by Michael Skeffington

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

From: Michael Skeffington <[email protected]>

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 <[email protected]>

---
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

2017-08-04 06:23:23

by Kalle Valo

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

Michael Skeffingfon <[email protected]> writes:

> From: Michael Skeffington <[email protected]>
>
> 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 <[email protected]>

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

2017-08-07 06:32:44

by Stanislaw Gruszka

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

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

2017-08-07 16:58:00

by Michael Skeffington

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

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 <[email protected]> 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