Dear all,

I have a simple Postfix policy server, and got a problem to reject sender login 
mismatch (sender != sasl_username) with Outlook 2016: user is able to specify a 
From: address, it would be any address you want, and the From: address is not 
passed to policy server.

I can reproduce this issue with a simple Python program:

*) construct mail message with forge sender address. e.g. 'From: 
<[email protected]>'
*) send email as normal/legal user "[email protected]" with smtp auth.
*) while sending email, specify the sender address as "[email protected]".
*) When user received the email, his MUA shows the address in 'From:' as sender.

In this case:

- address '[email protected]' is not available in policy server
- attributes 'sender=' and 'sasl_username' are '[email protected]'

So the question is, does Postfix parse the submitted mail message to get 
'From:' address? How can i overcome this?

Thanks for helping. :)

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