Address rewrite/sub-addressing with Regex

[alex9434]

Dear all,

I try to set-up address-rewriting/sub-address in Stalwart and blocking of specific addresses. The reason is that I use different email addresses for different organisations/senders as kind of "throwaway" so that I can block addresses that are resold and/or used for spam.

1. Sub-addressing/rewriting:
   I use specific email addresses for specific websites/use-cases, e.g., [email protected]. These are then rewritten to my actual address: [email protected]. Reason I use this specific format, is that there are bots out there that automatically try different combinations and then put you on spam lists if they get a delivered message. By using a complex format, I avoid that a bot accidentally gets it right.
   In postfix (in my case docker-mailserver) I use a postfix-regexp.cf for this:
   /^ab\.[a-z]+20[0-9][0-9]*@example.com/ [email protected]
   I tried to modify the example for sub-addressing from the documentation https://stalw.art/docs/smtp/inbound/rcpt
   but I am not successful. Even the example itself does not seem to work for me. Any idea how I can do that in Stalwart?

2. Blocking:
   When I notice an address is compromised/resold I want to reject it "550 5.1.2 Mailbox does not exist." or just send it to /dev/null. In postfix the approach is to set-up an alias in postfix-aliases.cf
   devnull: /dev/null
   and then list all the addresses in postfix-virtual.cf, e.g. (obviously these examples are just placeholders)

[email protected] devnull
[email protected] devnull
[email protected] devnull

This makes sure that I never see any email that is send to these compromised addresses.
How can I achieve something similar in Stalwart?
Thank you!

[mdecimus]

Hi, please check the envelope rewriting section of the documentation. You can use rewrite rules using expressions or with Sieve.

[alex9434]

Thank you!