
On Sun 15/Oct/2017 19:24:16 +0200 Mark Sapiro wrote:
Replacement of the From header is just a matter of reading the email headers into an array, making modifications if necessary and pushing the result, followed by the message body, out to Courier's sendmail clone. Basically:
if from_domain publishes bad DMARC: if Reply-To does not exist: copy From header to Reply-To Replace From with "On behalf of old_From" <postmaster@fmp.com>
I have seen it said that email addresses in display names in From: headers are a sign of spaminess. Thus, in the above I suggest that old_From should just be the display name part of the original From: or be munged in some way (replace '@' with ' at ' or ?) so it doesn't look like an email address.
I'm unclear how adding a Reply-To:, depending on users' clients is going to affect mailing list traffic. For an alternative, when the usual action is to reply to mailing list, it seems to me to be smoother to just mangle the From: so as to make it like so:
John Doe <john.doe@example.org.REMOVE.THE.TRAILING.PARTS>
Although the addition of capitalized anti-spam diversions in the domain part of email addresses is still en vogue in several mailing list, this method never gained traction. Why?