Previously the constraints in the authentication configuration of an
initiator were enforced only after all authentication rounds were
complete. This posed a problem if an initiator used EAP or PSK
authentication while the responder was authenticated with a certificate
and if a rogue server was able to authenticate itself with a valid
certificate issued by any CA the initiator trusted.
Because any constraints for the responder's identity (rightid) or other
aspects of the authentication (e.g. rightca) the initiator had were not
enforced until the initiator itself finished its authentication such a rogue
responder was able to acquire usernames and password hashes from the client.
And if a client supported EAP-GTC it was even possible to trick it into
sending plaintext passwords.
This patch enforces the configured constraints right after the responder's
authentication successfully finished for each round and before the initiator
starts with its own authentication.
Fixes CVE-2015-4171.
0020b25a45