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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>If my understanding is correct, for drivers that use their
own RSN IEs during association, a PMKID list is kept in the driver. This list is
kept in sync with its own list by the supplicant using add_pmkid, remove_pmkid
calls. Browsing through the supplicant code I cant find where the driver’s
PMKID entry is removed when a PMK cache entry is removed in the supplicant.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>One of the problems due to this is when a cache entry
expires on the station, the supplicant removes its own entry. Unaware, driver sends
the corresponding PMKID during reassociation and the AP jumps to 4 way
handshake. Handshake fails as supplicant is unable to find the entry. This loss
of sync leads to endless failed association attempts and stops only when the AP
does a full authentication. Understandably, some APs never do a full
authentication if a valid PMKID is found during association.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Am I missing something or is this really a problem?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks<br>
Gautam<o:p></o:p></span></font></p>
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