[exim] Force all local senders to authenticate

Hello list,

My knowledge of Exim got rusty a bit:)

I'd like to achieve two conditions within exim:

1. I'd like to force all local senders (+relay_from_hosts) to
authenticate before they can send out mail
2. I'd also like to ensure that while this is enforced, the
authenticated_id MUST be the same as the sender_address?

How do I achieve these, and at what level of processing?

Thank you for bearing with me.

-- 
Best regards,
Odhiambo WASHINGTON,
Nairobi,KE
+254733744121/+254722743223
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