[strongSwan] error handling

[Tobias Brunner]

Hi Anthony,

> ? will our application be able to detect them using ether: VICI “event
> callbacks” or “ErrorNotifyPlugin”

Why not just try it?

> Inacceptable Constraint check failed

You can't detect that specific error but ERROR_NOTIFY_PEER_AUTH_FAILED
will be triggered.

> IKE AUTH response errors

This triggers ERROR_NOTIFY_LOCAL_AUTH_FAILED.

Regards,
Tobias