IEEE8021X and WEP40
j at w1.fi
Sun Sep 6 14:05:03 EDT 2009
On Mon, Aug 03, 2009 at 02:22:10PM +0800, Zhu Yi wrote:
> I tried wpa_supplicant for 802.1X dynamic WEP with iwmc3200wifi driver.
> It worked for WEP104 but not WEP40. After some digging into the code, it
> turns out wpa_supplicant set WEP104 explicitly in file wpa_supplicant
> line 1112 (git version) function wpa_supplicant_associate:
> /* Assume that dynamic WEP-104 keys will be used and
> * set cipher suites in order for drivers to expect
> * encryption. */
> cipher_pairwise = cipher_group = CIPHER_WEP104;
> If I comment the "cipher_pairwise = cipher_group = CIPHER_WEP104" line,
> WEP40 works great with 802.1X on my Cisco Aironet 1200 AP. Jouni, Any
> reason we need to set WEP104 in this case? They should already be set to
> the correct values earlier in the same function.
wpa_supplicant does not know at this point what the WEP key length will
be. This can be determined only after having completed association when
receiving the EAPOL-Key frame from the authenticator. It sounds a bit
odd if a driver were to be unable to association if the key length here
does not match. Or does iwmc3200wifi reject the key configuration for a
different key length later when the key is actually being configured?
Jouni Malinen PGP id EFC895FA
More information about the HostAP