strongswan - security update

Alexander E. Patrakov discovered an issue in strongSwan, an IKE/IPsec
suite used to establish IPsec protected links.

When a client authenticate the server with certificates and the client
authenticates using pre-shared key or EAP, the constraints on the server
certificate are only enforced by the client after all authentication
steps are completed successfully. A rogue server which can authenticate
using a valid certificate issued by any CA trusted by the client could
trick the user into continuing the authentication, revealing the
username and password digest (for EAP) or even the cleartext password
(if EAP-GTC is accepted).