Bug Report

Context

Similar to the problem that mail in a box had, the included /etc/postgrey/whitelist_clients is outdated by years, the last entry is from 2015. The official current version can be found at http://postgrey.schweikert.ch/pub/postgrey_whitelist_clients

What is affected by this bug?

Many websites use mass-mailing services like MailChimp for their confirmation mails. Those services use a large pool of servers that all get greylisted individually. Also, they use very conservative intervals when reacting to being greylisted so confirmation tokens are often already invalid when the mail eventually goes through.

How do we replicate the issue?

1. Sign up for a new account with something that uses MailChimp / Mandrill (I found it while making an account for the game Alchemy Star but I think Twitch is also affected)
2. Wait
3. Request another confirmation mail
4. Wait some more
5. See that the mails take 20 minutes or more

Behavior

Actual Behavior

Every mail gets greylisted individually

Expected Behavior

MailChimp (along with some others) has been on postgrey's whitelist since 2018 so it should not be greylisted.

Workaround

I added the following to my config/user-patches.sh:

#!/bin/bash
curl http://postgrey.schweikert.ch/pub/postgrey_whitelist_clients -o /etc/postgrey/whitelist_clients
service postgrey reload