When Linux has Path MTU discovery enabled, it sets by default the DF bit
on all outgoing datagrams, also UDP ones. If a RADIUS message is bigger
than the smallest MTU size to the target, it will be discarded.
This effectively limits RADIUS messages to ~ 1500 Bytes, while they can
be up to 4k according to RFC2865. In practice, this can mean trouble
when doing EAP-TLS with many RADIUS attributes besides the EAP-Message.
[Bug 326]
Allow the user to set the IP address of the eapol_test client. This if
very useful when you have a machine with many interfaces and want to use a
particular one for testing RADIUS connectivity. For instance when I run the
national eduroam proxy I can only connect to other server from a particular
address, an our machine happens to have several IPs. So if I want to run
connectivity tests, I must make sure that my test uses a particular
interface. The -A option allows one to set this).
(jm: cleaned up to use radius configuration structure instead of global
variable for the address and added IPv6 support)