On Thu, 2009-10-08 at 21:26 -0400, [email protected] wrote: > It looks like "kerberos" has to be folded (maybe > n-folded) somehow so that I can use it as my IV, but I am not quite > sure I'm on the right track.
You do need to n-fold "kerberos" to the block size (128 bits). I'm not sure I can describe n-fold better than the RFC; I suggest using the test vectors from RFC 3961 to determine when you've gotten it right. You do not need to fiddle with IVs. Once you have n-folded "kerberos" to 128 bits, you just encrypt those 128 bits with the intermediate key to produce the 128 bits of the final key. For AES-256, you encrypt the first 128 bits of the final key with the intermediate key (again) to produce the other 128 bits of the final key. Again, I suggest using the test vectors from RFC 3962 as an authoritative check, in case you're making incorrect assumptions about the usage of ktpass.exe. Best of luck! ________________________________________________ Kerberos mailing list [email protected] https://mailman.mit.edu/mailman/listinfo/kerberos
