* Revert "Guard against SMTP smuggling", commit faf23f150c, by restoring the setting to its default.
* Revert "[security] SMTP smuggling: update short term fix (#2346)", commmit e931e103fe, by restoring the setting to its default.
* Set smtpd_forbid_bare_newline=normalize.
Port 465 with "implicit" (i.e. always-on) TLS is a more secure approach than port 587 with explicit (i.e. optional and only on with STARTTLS). Although we reject credentials on port 587 without STARTTLS, by that point credentials have already been sent.
* SC2068: Double quote array expansions to avoid re-splitting elements.
* SC2186: tempfile is deprecated. Use mktemp instead.
* SC2124: Assigning an array to a string! Assign as array, or use * instead of @ to concatenate.
* SC2102: Ranges can only match single chars (mentioned due to duplicates).
* SC2005: Useless echo? Instead of 'echo $(cmd)', just use 'cmd'.
@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.
The default timeout for Postfix's maximal_queue_lifetime and bounce_queue_lifetime is 5 days. This is way too long if you expect someone to have an answer and after 5 days you'll get the message that it's not delivered. This disrupts communication. It would be more responsive if the user got the 'can't deliver' error after 24 hours.
Modify outgoing_mail_header_filters and mail-postfix.sh
files to result in the primary hostname, and the public
ip of the server showing in the first mail header route
instead of unknown and 127.0.0.1. This could help lower
the spam score of mail sent from your server to some
public mail services.
A lot of legit mail servers try again between 200 and 285 seconds, then
3 hours later. Why? RFC is not strict about retry timer so postfix and
other MTA have their own intervals. To fix the problem of receiving
these e-mail really latter, I reduced the delay of postgrey to
180 seconds (default is 300 seconds).
The submission port began offering SSLv3.
With `encrypt`, the smtpd_tls_protocols option is ignored and smtpd_tls_mandatory_protocols must be set instead.
see e39b777abc
Even though SMTP (on port 25) is typically opportunistic and a MitM attack can't be prevented, we may as well only offer ciphers that provide some level of security. If a client is so old or misconfigured that it doesn't support newer ciphers, it should hopefully fall back to a non-TLS connection.
Postfix's default was basically anything goes (anonymous and 40-bit ciphers!). Google's MTA's only offer ciphers at 112 bits at greater, and this change approximates that with Postfix's "medium" setting.
Fixes#371
This disallows aNULL and other bad ciphers in the Postfix submission server.
I missed an option in 45e93f7dcc recommended by the blog post I was reading.
Fixes#389.
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.
nginx/postfix use a new pre-generated dh2048.pem file. dovecot generates the bits on its own.
ssllabs.com reports that TLS_DHE ciphers went from 1024 to 2048 bits as expected. The ECDHE ciphers remain at 256 bits --- no idea what that really means. (This tests nginx only. I haven't tested postfix/dovecot.)
see https://discourse.mailinabox.email/t/fips-ready-for-ssl-dhec-key-exchange/76/3
