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  • Jérôme Pouiller's avatar
    e5da5fbd
    staging: wfx: fix CCMP/TKIP replay protection · e5da5fbd
    Jérôme Pouiller authored
    
    
    To enable the TKIP/CCMP replay protection, the frames has to be
    processed in the right order. However, the device is not able to
    re-order the frames during BlockAck sessions.
    
    Mac80211 is able to reorder the frames, but it need the information
    about the BlockAck sessions start and stop. Unfortunately, since the
    BlockAck is fully handled by the hardware, these frames were not
    forwarded to the host. So, if the driver ask to mac80211 to apply the
    replay protection, it drop all misordered frames.
    
    So, until now, the driver explicitly asked to mac80211 to not apply
    the CCMP/TKIP replay protection.
    
    The situation has changed with the API 3.4 of the device firmware. The
    firmware forward the BlockAck information. Mac80211 is now able to
    correctly reorder the frames. There is no more reasons to drop
    cryptographic data.
    
    This patch also impact the older firmwares. There will be a performance
    impact on these firmware (since the misordered frames will dropped).
    However, we can't keep the replay protection disabled.
    
    Signed-off-by: default avatarJérôme Pouiller <jerome.pouiller@silabs.com>
    Link: https://lore.kernel.org/r/20200701150707.222985-12-Jerome.Pouiller@silabs.com
    
    
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    e5da5fbd
    staging: wfx: fix CCMP/TKIP replay protection
    Jérôme Pouiller authored
    
    
    To enable the TKIP/CCMP replay protection, the frames has to be
    processed in the right order. However, the device is not able to
    re-order the frames during BlockAck sessions.
    
    Mac80211 is able to reorder the frames, but it need the information
    about the BlockAck sessions start and stop. Unfortunately, since the
    BlockAck is fully handled by the hardware, these frames were not
    forwarded to the host. So, if the driver ask to mac80211 to apply the
    replay protection, it drop all misordered frames.
    
    So, until now, the driver explicitly asked to mac80211 to not apply
    the CCMP/TKIP replay protection.
    
    The situation has changed with the API 3.4 of the device firmware. The
    firmware forward the BlockAck information. Mac80211 is now able to
    correctly reorder the frames. There is no more reasons to drop
    cryptographic data.
    
    This patch also impact the older firmwares. There will be a performance
    impact on these firmware (since the misordered frames will dropped).
    However, we can't keep the replay protection disabled.
    
    Signed-off-by: default avatarJérôme Pouiller <jerome.pouiller@silabs.com>
    Link: https://lore.kernel.org/r/20200701150707.222985-12-Jerome.Pouiller@silabs.com
    
    
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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