How to handle email?

Question

System administration

Hello colleagues!
There was such task: there are some mailboxes in one domain. And there is a box that should be a single "entry point" for clients. When a letter was received at the "entry point", if some correspondence was conducted from its sender's address with someone from other "internal" addresses, a copy of the letter was automatically sent to the address with which the sender corresponded.
I'll try to explain in a simpler way:
I have the address "[email protected]".
The organization has the address "[email protected]"
There is a client with the address "[email protected]"
I send some letter to "[email protected]" from my address, the postal system remembers it. Subsequently, if the client writes to "[email protected]", my address "[email protected]" should receive a copy of the letter that was originally sent to "[email protected]".
Twisted dovecot and postfix, somehow clarity did not increase. Are there tools that can solve this problem, having the ability to further expand this functionality (for example, automatically distribute copies of letters to managers with an even distribution of the number of hits). At the same time, I really want not to erect any additional applications for managers, or all sorts of web muzzles, because the organization uses The Bat!

Answer 1

The tool exists, it is called sieve, it is fastened to any MTA, as far as I know. Dovecot has a standard dovecot-sieve extension. Letters are processed at the moment they are placed in the client's mailbox ( before they enter the Inbox). But you will have to write the processing yourself.