by ptufts » Tue Jan 24, 2023 7:23 pm
Apologies if this is the wrong place to file a bug report / feature request for mail forwarding for domains. I orig. sent this to support and they recommended that share it as a feature request in the forums.

Summary: the member tools domain mail forwarding form blocks emails with plus signs, cites obsolete RFC 822

details

The domain email forwarding form on sonic.net incorrectly blocks emails with plus signs (eg username+foo@sonic.net) in the "points-to" field and pops up an error citing the obsolete RFC 822.

Depending on how you look at this, it's a bug report - don't implement an obsolete RFC and throw an error citing it - or a feature request - please update the logic in https://members.sonic.net/email/domalias/index.php to comply with RFC 2822 which supersedes 822 and allows plus signs (nb: sonic's mail server already supports plus signs, this is an issue with the form logic in https://members.sonic.net/email/domalias/index.php)

To reproduce this bug:

Go to the member tools domain alias section:

https://members.sonic.net/email/domalias/

Select a domain you own that is hosted at sonic.net.

Get redirected to

https://members.sonic.net/email/domalias/index.php

Add New Domain Email Alias with a left hand value of * (asterisk, a catch-all redirect) and a right hand email address with a valid sonic mailbox plus a plus sign and text (eg user+foo@sonic.net)

Result: a popup error warning: "the rule violates RFC 822"

Expected outcome: forwarding mail to a plus sign address per RFC 2822, which supersedes 822.

Technical commentary:

RFC 822 does not allow plus signs in emails, however RFC 2822 explicitly makes 822 obsolete and does allow plus signs.

See RFC 2822 Sec 3.4 which defines "address" and refers to 3.2.4 for the valid characters (atoms).

The spec for 3.2.4 allows plus signs as valid characters.

https://www.ietf.org/rfc/rfc2822.txt