Re: WPA support

[Dan Williams <dcbw redhat com>]

On Mon, 2 May 2005, Tim Warberg wrote:

> On 5/2/05, Dan Williams <dcbw redhat com> wrote:
> > > WPA_Supplicant already have a mode where SSID scanning and association
> > > is controlled by user and i think this is a good base for
> > > NetworkManager integration. Also for now i think it would be a good
> > > idea to let wpa_supplicant configure hardware for WPA using it's
> > > drivers at least until WPA is completely implemented through Wireless
> > > Extension and kernel modules support this.
> > 
> > Yes, this had been more or less my idea.  Basically, wpa_supplicant is
> > too smart in its default mode, and what we need is a "connect to this
> > access point on this interface with this passphrase", and nothing more.
> > We do not want wpa_supplicant to do its own scanning, its own
> > config-file parsing, or anything else.  Users should not have to edit
> > the wpa_supplicant config file, since that information is stored in the
> > user session by the info-daemon in NetworkManager's world.  We need
> > wpa_supplicant in a "slave" mode.
>  
> > Jouni has said that approach is acceptable, I think somebody just needs
> > to fix up the patches for it.
> 
> I'll give it a try. Hopefully I'll end up with something Jouni find
> acceptable :)
> 
> Perhaps the easiest way is a syntax similar to the one in the config
> file. Something like:
> interface=wlan0;driver=SomeDriver;ssid="SomeSSID";proto=WPA;key_mgmt=WPA-PSK;pairwise=TKIP;group=TKIP;psk="MyVerySecretPassword"

One complication is that wpa_supplicant request some additional information from 
scans, specifically the RSN pre-auth tags from APs and whatnot.  Since 
_NetworkManager_ is doing the scanning, we'll need a way to pass that data to 
wpa_supplicant.  I'm not sure how long RSN pre-auth tags are, but they appear to 
be at least 22 bytes.

Also, while we get driver information from HAL, we may need to let 
wpa_supplicant determine the driver to use.  I'm not sure about that since I 
haven't seen the wpa_supplicant driver selection code, if any.  Or are drivers 
manually set in the config file?  In any case, we can figure out what the base 
driver is from HAL and pass that on in some form to wpa_supplicant.

But if the above string-type thing works to be passed over the control socket to 
wpa_supplicant, that sounds good.

Hope to see some WPA stuff soon!

Dan