I have an OpenSMTPD / Dovecot installation on an OpenBSD server. I recently came across an issue where Dovecot LMTP would reject a message sent to a local user from an address which contains a single apostrophe (e.g.
firstname.lastname@example.org). Apparently apostrophe, as well as a number of other special characters are valid characters in the local part of the email address (that's everything to the left of the
The message I get in the logs is:
Jun 14 11:57:34 atlantic smtpd: 21749fd12ac76b57 mda delivery evpid=56aed6237d6444a0 from=<email@example.com> to=<firstname.lastname@example.org> rcpt=<email@example.com> user=me delay=0s result=PermFail stat=Error ("mail.lmtp: LMTP server error: 501 5.5.4 Invalid FROM: Invalid character in localpart")
example.com is external domain and
example.org is a local one.
The part of the message:
LMTP server error: 501 5.5.4 Invalid FROM: Invalid character in localpart is returned by
My question is: does anyone know of a configuration option, similar to
auth_username_chars which lists valid characters in the email address, to stop Dovecot LMTP from rejecting such emails? or maybe you know another way of getting it to accept an email from such address?
My dovecot version is:
$ dovecot --version 184.108.40.206 (7ec6d0ade)
And in case that makes any difference, I'm running OpenBSD 6.5 patched to 005_libssl.