Hi,
Trying to authenticate third-party SIM cards is a hack. It will always be a hack. You MUST have the SIM keys in order to do proper, secure, authentication.
I understand and agree. Do you have any practical advice on how to get the SIM key? People who are implementing EAP-SIM/Freeradius in production environments, what are they doing to get them?
Issue your own SIMs. Operators will never give out Ki. If they're properly equipped, the keys are locked in a HSM in their AuC ... Also, they might not even implement any "known" algorithm at all, an operator is free to select whatever they want since all that matters is that the same algo is in the SIM and in their AuC. Also, fyi some modern SIMs have protections and can "self destruct" if they receive too many auth queries (so you can submit like 10k+ request to build a large DB of challenges -> SRES / Kc). Cheers, Sylvain