Re: [PATCH] ath9k: Add module parameter to disable hardware crypto

[pat-lkml <pat-lkml@erley.org>]

pat-lkml wrote:
> Jouni Malinen wrote:
>> On Tue, Feb 24, 2009 at 09:24:32AM -0500, pat-lkml wrote:
>>
>>> With this patch, and nohwcrypt=1, I get the following in hostapd (this
>>> system runs as an access point) when I try to associate with a client.
>>>
>>> I can't say whether this is a hostapd problem or an ath9k problem yet,
>>> but it's a different behavior than with nohwcrypt=0 or without this 
>>> patch.  With this patch, wpa2 works perfectly, as without it, as well
>>> as wep working perfectly.  
>> Are you saying that you get different behavior from hostapd when
>> comparing nohwcrypt=0 and nohwcrypt=1 (i.e., no changes in the driver
>> code, just the module parameter change)?
> 
> Yes.  
> 
>>> I wouldn't call this report a 'ACK/NACK' report as it has caused no
>>> new problems, nor fixed any old problems.  Unfortunately I don't have 
>>> a log around of the old behavior right now, for comparison.  I just 
>>> wanted to report what I've found based on this patch.
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: sending 1/4 msg of 4-Way Handshake
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: EAPOL-Key timeout
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: sending 1/4 msg of 4-Way Handshake
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: EAPOL-Key timeout
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: sending 1/4 msg of 4-Way Handshake
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: received EAPOL-Key frame (2/4 Pairwise)
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: invalid MIC in msg 2/4 of 4-Way Handshake
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: received EAPOL-Key 2/4 Pairwise with unexpected replay counter
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: received EAPOL-Key 2/4 Pairwise with unexpected replay counter
>>> wlan0: STA 00:1f:a7:70:2d:8d WPA: EAPOL-Key timeout
>> Which client are you using? Are you sure that the passphrase/PSK is set
>> correctly? The nohwcrypt patch should make absolutely no difference for
>> this part (this is key handshake which in the initial phase is sent
>> without encrypted EAPOL-Key frames, so neither sw nor hw crypto used).
> 
> I've tried 3 different clients with identical behavior:
> 
> 1.  Playstation 3
> 2.  Dell Axim / WM6
> 3.  ath5k Laptop
> 
> I get that (afore mentioned invalid MIC in msg 2/4) with nohwcrypt=1, while
> nohwcrypt=0 I get 'STA Detected Michael MIC error' during stage 3 I believe. 
> 
> I'll have more time after about 6:00PM EST to test this and provide the full
> logs of each client associating, along with  wpa_supplicant logs.  I'm running
> git hostapd, and I've NEVER had wpa1 work correctly with it, which is why I said
> that that report wasn't an 'ACK/NACK' just reporting that I see a difference in 
> behavior with it.  
> 
> Pat

Ok, I feel VERY sheepish now.  In doing further testing, I discovered a typo in my
hostapd.conf for the wpa config, specifically, an extra char that snuck into my wpa
pass phrase.  Use nohwcrypt=1, hostapd now works perfectly with wep/wpa/wpa2, while
with nohwcrypt=0, I get errors (that I'll need physical access to my computer to 
debug/log) in wpa only.  I'm testing with my usual, rate limited scp transfer over 
wireless right now, as previous 'issues' have arisen when a re-key occurs during a 
transfer.

Pat Erley