OpenDMARC report messages, while potentially useful for peer operators of mail servers, are abusable and should not be enabled by default. This change prioritizes the safety of the Box's reputation.
Configures opendmarc to send failure reports for domains that request them, including when p=none.
The emails are sent as the package default of package name and user@hostname: OpenDMARC Filter <opendmarc@box.example.com>
Note I have been running this for several months with a configuration I did not include in the PR to have reports BCC'd to me (FailureReportsBcc postmaster@example.com). Very low load for my personal server of rarely more than a dozen emails sent out per day.
I am not familiar with editing scripts, so apologies in advance and please feel free to correct me.
Because Mailman reformats headers it breaks DKIM signatures. SPF also does
not apply in mailing lists. This together causes DMARC to fail and mark the
email as invalid. This fixes DKIM signatures for Mailman-based mailing lists
and makes sure DMARC test is passed.
@joshdata squashed pull request #1398, removed some comments, and added these notes:
* The old init.d script for the management daemon is replaced with a systemd service.
* A systemd service configuration is added to configure permissions for munin on startup.
* nginx SSL settings are updated because nginx's options and defaults have changed, and we now enable http2.
* Automatic SSHFP record generation is updated to know that 22 is the default SSH daemon port, since it is no longer explicit in sshd_config.
* The dovecot-lucene package is dropped because the Mail-in-a-Box PPA where we built the package has not been updated for Ubuntu 18.04.
* The stock postgrey package is installed instead of the one from our PPA (which we no longer support), which loses the automatic whitelisting of DNSWL.org-whitelisted senders.
* Drop memcached and the status check for memcached, which we used to use with ownCloud long ago but are no longer installing.
* Other minor changes.
On some machines localhost is defined as something other than 127.0.0.1, and if we mix "127.0.0.1" and "localhost" then some connections won't be to to the address a service is actually running on.
This was the case with DKIM: It was running on "localhost" but Postfix was connecting to it at 127.0.0.1. (https://discourse.mailinabox.email/t/opendkim-is-not-running-port-8891/1188/12.)
I suppose "localhost" could be an alias to an IPv6 address? We don't really want local services binding on IPv6, so use "127.0.0.1" to be explicit and don't use "localhost" to be sure we get an IPv4 address.
Fixes#797
* Add a migration to delete any existing DKIM key so that existing machines get a fresh 2048-bit key. (Sadly we don't support key rotation so the change is immediate.)
* Because the DNS record for a 2048-bit key is so much longer, the way we read OpenDKIM's DNS record text file had to be modified to combine an arbitrary number of TXT record quoted ("...") strings.
* When writing out the TXT record value, the string must be split into quoted ("...") strings with a maximum length of 255 bytes each, per the DNS spec.
* Added a changelog entry.
Currently MiaB creates 1024 bit keys which is seen as a minimum standard
by several providers such as Google who already uses a 2048 bit key.
Increasing the keysize beyond 2048 is an issue as it often goes beyond
supported DNS record sizes.
I added OpenDMARC's milter in fba4d4702e. But this started
setting Authentication-Results headers on outbound mail with failures. Not sure why it
fails at that point, but it shouldn't be set at all. The failure might cause recipients
to junk the mail. See #358.
This commit removes the milter from the SMTP submission (port 587) listener.
