Renewal of the group key when countermeasures are initiated
anne.lambert at thomson.net
Thu Aug 16 06:18:45 EDT 2007
I am building a driver which is using a part of hostapd code as WPA
Authenticator. The AP management is already taken care of so I just need
to interact directly with the wpa module.
When countermeasures are initiated the
ieee80211_tkip_countermeasures_start function request the renewal of the
group key by calling wpa_gtk_rekey. In doing so, it bypasses the
wpa_group state machine and therefore does not update the key in the
driver (eg wpa_auth_set_key is never called). This means that after
countermeasures ended, the stations get the new group key but the access
point is still using the group key generated at initialisation.
I added a call to wpa_auth_set_key in wpa_gtk_rekey and this seems to
solve the problem. Do you think this is a problem of hostapd or in the
way I have been using it?
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