Yes, putting the From: into Reply-To: is a good idea to ensure the reply button in receiver´s client doesn't break. But remember to ONLY do it when Reply-To: is not present.
To avoid removing important information from the email, like the original sender, it can be good to always add a header like X-Original-Sender with the original from: when rewriting in this way.
OTOH I think this type of rewriting should be done in the MTA that is responsible for sending the email off the server, NOT in dovecot/sieve.
In exim theres already built-in support for this type of rewriting, and I have such rewriting on all domains for which are forward-only - to avoid SPF errors.
-----Ursprungligt meddelande----- Från: dovecot-bounces@dovecot.org dovecot-bounces@dovecot.org För Marc Roos Skickat: den 25 oktober 2020 16:49 Till: dovecot dovecot@dovecot.org Ämne: forwarding email with sieve of spf domains
Say someone has setup spf for his domain and sends an email to a user that has in roundcube enabled the sieve forward. If the message is forwarded without altering the message headers, this could result in a message being blocked or not relayed, because sending hosts ip, is not in the spf of the from: domain.
Possible solutions are:
- add option if enabled, it replaces the From: with that of the email address of the sieve user. (Maybe move the original sender to the Reply-To header? Maybe exception for 'internal' forward?)
- Upon processing the message, check the spf records, if they are enforced, do the above, otherwise do nothing.