Thursday, March 31, 2022

iRedMail on CentOS 8 as aggregating mail server

CPU fan went on my home mail server (that pulls in email from all my accounts) and since it is so old (a Core 2 Duo) I decided to just use one of the old security camera servers left over from an upgrade instead.

Things assumed you know

Note I use vi to edit files since it is including in almost every Linux and Unix install. If you are not familiar with any available editors look at this vi Cheat Sheet for help.

To see active lines in move config files you can use the command

grep -v "#" /etc/postfix/main.cf | grep -v "^[[:space:]]*$"

where /etc/postfix/main.cf  is the config file you want to see the active lines of. 

For the examples below I'm using these values. Where you see them replace with your own.

  • host=mail
  • domain=dea42.us
  • full qualified name=mail.dea42.us
  • server IP=10.10.2.200
  • end email address = deabigt@dea42.us
  • placeholder for passwords = P@$$w0rd

Unless otherwise mentioned all commands should be run as root (or add sudo in front of them)

A typo can cause emails to be lost so you will want to have a server to test fetching emails from that you can limit what is in the "inbox". Either an account that has separate imapped folders (not gmail) or test account you can send test emails to like a gmail account you do not use for anything important. Once you think you have things working you can try a few emails a time with you test account and even your main account if it has separate folders.

And things you should

I tried to go down the road of installing CentOS 7 but iRedMail makes that virtually impossible. You would have to hack it so much you might as well just install it manually.

The only web server option is Nginx. If you do not select it you will not get web mail.

Steps:

Get CentOS 8 Stream

Note the "DVD" ISOs will not fit on a DVD. You will need a Blu-Ray or USB stick 16 GB or higher. 
If you need help with that see How to Burn an ISO File to a USB Drive. Be sure to create a user other than root and put them in the wheel group.

Note after install you will want to turn on your network interface as it is off by default. Also the name local.localhost for the computer name is misleading. If you enter name.domain as in mail.dea42.us it changes the name to mail-dea42-us.

the simple fix is to run the command
hostname -b mail.dea42.us

Install iRedMail

iRedMail gets you a web mail server without a lot of config file editing but note the "And things you should" above.

The above link is for iRedMail 1.4 but has some commands missing in the official doc.
Ignore the implied CentOS 8 option. As of this writing CentOS 8 is EOL and your only non stream option is 7.9.

Note some stuff is in CentOS 8 stream so ignore any already installed "errors".

SOGO is not selected by default. I added it though I doubt I'll need it. Note running yum update will get errors trying to update this due to a library conflict. 

Note I have a thing about putting large amounts of expanding data in the / partition so for mail storage I used /home/var/vmail instead of /var/vmail.

Once done, go add your user to the mail system with the iRedMail panel by pointing your browser to https://10.10.2.200/iredadmin (note I'm using the IP here since it is on my local network).

To start you can only log into the admin panel and web mail as postmaster@dea42.us. As the last bit of the install says you really want to read iRedMail.tips and move it to a secure location since it contains login info in plain text.

Bringing over old data.

Once you have you web mail users created you can tar up your old emails in the user's Maildir folder. May be under user's home or some convoluted  vmail path. For instance for deabigt@dea42.us on the old server was /home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2018.03.23.20.35.01/Maildir and on the new server /home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/Maildir. I moved the Maildir folder to Maildir.bak just to be safe but no really needed.

You can also export and import your filters but that is it without access to the DB. To get indenties for example you will need to export tables, possibly modify the SQL and then import in to the new DB.

Install phpMyAdmin

Note iRedMail sets up the html folder to be the more standard /var/www/html instead of Nginx's normal  /usr/share/nginx/html/

Note use this Generate blowfish secret link to generate a random encrypt key of the 32 characters needed. 

Also the old php.info() is disabled by default. I usually change it to a honeypot anyway so try making /var/www/html/info.php this instead to test php and log any malware looking for it.
<html>
<head><title>honeypot Access logger</title></head>
<body><h1>Honeypot logger</h1>
<?php
$log="/var/log/nginx/honeypot.log";
$el = date("Y-m-d h:i:s",time())." ".$_SERVER['REQUEST_URI'] . " accessed from " . $_SERVER['REMOTE_ADDR'] . " via " . $_SERVER['SERVER_PROTOCOL'] . "- " . $_SERVER['REQUEST_METHOD'] . " with query " . $_SERVER['QUERY_STRING'];
$hl = error_log($el.PHP_EOL, 0);
echo "<br>Logged $el - $hl <br><br>";
foreach (getallheaders() as $name => $value) {
    echo "$name: $value<br>";
    $el =  $el . " :" . $name .": " . $value;
}
foreach ($_REQUEST as $name => $value) {
    echo "$name: $value<br>";
    $el =  $el . " :" . $name .": " . $value;
}
$hl = error_log($el, 3, $log);
?>
</body>
</html>

You can then add a cron script to notify you if something hits this and you will get more info than you probably want about what accessed it. For example run
crontab -e
and add this to the bottom

# Honeypot checker
15 * * * * /bin/grep -v 10.10.2.183 /var/log/nginx/honeypot.log

Every hour at a quarter past if there is anything in there not from 10.10.2.183 the user (root assumed) will get and email with the info till you empty the log. I'm assuming a small network here where this is unlikely to get many hits. Something exposed to the internet should of course be a lot more complex.

Now you should be able to export and import data from your old system DB into the new one. Though you might need to edit user IDs if not added in same order. 

Fetchmail

This is the aggregating bit. It will go get mail from other servers and deliver it here. Webmin has a simple web interface for this but iRedMail does not. Installing both could cause conflicts but the free iRedMail admin panel seems to do so little it is probably worth the risk.

Install Webmin 


Getting to actually work

After all that it appears it did not get setup correctly since fetchmail retrieved email but postfix then tried to forward them but could not connect to localhost according to logs.

Issues (found) and fixed while debugging:
  • Run cp /etc/hosts /var/spool/postfix/etc/hosts (logs said they were out of sync)
  • Run cp /etc/localtime /var/spool/postfix/etc/localtime (logs said they were out of sync)
  • On Roundcube check folders are all subscribed. (I found many of mine were not so were hidden.)
  • Add no sslcertck to my user's ~/.fetchmailrc since Webmin does not seem to have a way to add it. (Testing server had a self signed cert.)
  • Add Delivered-To ignore to header checks. (Fixes issues with postfix forwarding to the original to.) Details on how to do that here. 
  • Add  --sslproto~TLS1.2+  to fetchmail command in Webmin. (Test server did not do TLS1.3)
https://10.10.2.200:10000/config.cgi?module=fetchmail&section=line1&search=&nnext=Next&xnavigation=1

I sorted the above by going back to basics, testing each link in the chain. To start testing open an extra window and as root run
tail -f /var/log/maillog
to see any errors while running mail tests.


Test Postfix

For this to work you may need create the tmp, new and cur email folder for the test user. I'm using deabigt for my username which Roundcube had already created them for. Type the stuff in bold, stuff in grey are the responses you should see (or something close to).

telnet localhost smtp (you will be asked if you want to install if you have not already) 

Trying ::1...
Connected to localhost.
Escape character is '^]'.
220 localhost.localdomain ESMTP Postfix
ehlo localhost
250-localhost.localdomain
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
mail from:<deabigt@dea42.us>
250 2.1.0 Ok
rcpt to:<deabigt@dea42.us>
250 2.1.5 Ok
data
354 End data with <CR><LF>.<CR><LF>
This is a test email from telnet
.
250 2.0.0 Ok: queued as 62AD46011817
quit
221 2.0.0 Bye
Connection closed by foreign host.

If you get the queued line you know it tool it OK.

Testing Dovecot

Next we want to check we can read our emails from via Dovecot.

Run
netstat -tunap | grep dovecot
to see what port(s) dovecot is listening on

Short version. Run
openssl s_client -connect 10.10.2.200:993
or
openssl s_client -connect 10.10.2.200:143 -starttls imap

You should see bunch of SSL handshake stuff then 
. OK Pre-login capabilities listed, post-login capabilities have more.
as the last line.

Send (with username a password for user you have set up).
a login "deabigt@dea42.us" "P@$$w0rd"
and you should see
* CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SNIPPET=FUZZY SPECIAL-USE
a OK Logged in

Just to be sure send
c list "" *
and you see something like this (depending of what folders you created)
* LIST (\HasNoChildren \Sent) "." Sent
* LIST (\HasNoChildren \Drafts) "." Drafts
* LIST (\HasNoChildren \Trash) "." Trash
* LIST (\HasNoChildren) "." INBOX
c OK List completed (0.001 + 0.000 + 0.001 secs).

Then logout with
e logout
and see
* BYE Logging out
e OK Logout completed (0.001 + 0.000 secs).
closed

If you get and error like:

system library:connect:Connection refused:crypto/bio/b_sock2.c
Dovecot is not running or you IP address or port is wrong.


Check sieve

In my case messages where not getting delivered so the next step is to check the sieve log. For my test user it is at 
/home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/sieve/dovecot.sieve.log
In there I found 
error: from=postmaster@dea42.us, envelope_sender=MAILER-DAEMON, subject=Rejected: , msgid=<dovecot-1648226282-16727-0@mail-dea42-us>, size=3642, delivery_time=42ms, failed to store into mailbox 'INBOX': Quota exceeded (mailbox for user is full).
Since the email was too and from me it went nowhere. From Webmin it appeared my quota should be unlimited but digging I found in /etc/dovecot/dovecot.conf that no default quota set as these lines were commented out.
    quota_rule = *:storage=1G
    quota_rule2 = *:messages=0
    quota_rule3 = Trash:storage=1G
    quota_rule4 = Junk:ignore
so I uncommented them and restarted Dovecot. (I bumped the top rule to 100G since I had the space).
That sorted that. It appears my sieve rule to send emails without a subject to Junk even worked.

To be sure though you should run sieve-filter with some test emails.
sieve-filter -D -v -W -C -u "deabigt@dea42.us" "/home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/sieve/dovecot.sieve" "AAA_filterTest" keep
Note AAA_filterTest is an email folder I created to stick test emails in.
That should have showed me how the emails in that folder would be filtered / sorted but instead I got
sieve-filter(deabigt@dea42.us): Error: user deabigt@dea42.us: Auth USER lookup failed
sieve-filter(root): Fatal: Internal error occurred. Refer to server log for more information.
Where is a whole mix of perms to get around for this to work. How I got it to finally work was to
chmod 7755 /usr/bin/sieve-filter
chmod 711 /home/deabigt
then as user deabigt create a script chkRules.sh with this line
sieve-filter -D -v -W  "/home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/sieve/dovecot.sieve" "AAA_filterTest" keep
and another script runRules.sh with this line
sieve-filter -e -D -v -W  "/home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/sieve/dovecot.sieve" "AAA_filterTest" keep
Make both executable with
chmod 744 *Rules.sh


Enable fetchmail schedule

Once you have everything tested (including options below) the last thing you should do it setup and enable fetchmail's schedule in the Webmin interface. This will setup cron job(s) to pulls from the servers. 


Optional

A few other things I wanted for my setup 

UPS monitor

Install apcupsd to shutdown server when UPS is ready to quit.

VNC

I want root DB access only from the console but the server will be in another building so VNC should let me run a browser there remotely.

Note VNC is built in for CentOS 8 Stream. If you install and enable something like TigerVNC server you may not be able to login on the console much less remotely with a VNC viewer.
Also RealVNC appears to still not support TLS so make sure to follow instructions to the bottom.

It also seems that the user must be logged in on the console to connect as well. Given that and I could not seem to get past the black screen issue either so I moved on for now. And setup XMing instead. Though I used SecureCRT instead of Putty.

Top 25 Nginx Web Server Best Security Practices

Getting more Roundcube options to work

The basic / free version of iRedmail does not install the mark junk and spell check options / plugins I want installed so I needed to run installer manually. 

To be safe, make backups of /opt/www/roundcubemail/composer.json and /opt/www/roundcubemail/config/config.inc.php before proceeding.

To enable it you first need to enable the installer again. They locked it down multiple ways. To reverse this you need to:
  • chmod 777 /opt/www/roundcubemail/installer
  • chmod 555 /opt/www/roundcubemail/config/config.inc.php
  • ln -s  /opt/www/roundcubemail/installer/ /opt/www/roundcubemail/public_html/installer
  • edit /etc/nginx/templates/roundcube.tmpl and comment out (add # at beginning of line) to the location ~ ^/mail/(bin|config|installer|logs|SQL|temp|vendor)($|/.*) { deny all; } line.
  • systemctl restart nginx
  • Add $config['enable_installer'] = true; to the end of  /opt/www/roundcubemail/config/config.inc.php

You can point your browser at https://10.10.2.200/mail/installer.

Step 1 

Shows you what support structure is installed. In this case just imagick and some unneeded DBs should be missing. If you want imagick installed see Amazon Linux 2: Installing ImageMagick for PHP 7.4 even though you probably have php version 7.2 installed these instructions will still work if you sub nginx for httpd in the restart services step.

Refreshing the browser window where you have the installer should now look like this.
Roundcube installer step 1

Since you already have a config.inc.php installed the Next button will take you straight to step 3. Instead click on Create config (step 2).

Step 2

This is where all the options are. The one not enabled by iRedMail that I enabled were (from top to bottom of page).
  • Enabled enable_spellcheck
  • I changed smtp_server to my hosted email system since most email systems these days block email coming from "residential IPs". 
  • Changed htmleditor from never to on reply to HTML message only
  • Enabled additional_message_headers, archive, emoticons, identity_select, jqueryui, markasjunk, newmail_notifier, show_additional_headers, subscriptions_option, userinfo and vcard_attachments.
Check UPDATE_CONFIG button at bottom of page and it saves your changes and reloads the page. Click CONTINUE button at top of page to go to step 3.

Step 3

Mainly shows you that installer did not seriously mess up the config file. It also give you a quick chance to check connections to the smtp and Dovecot servers. So you are done with the installer and can disable it again. Again personally I'd just remove the link, /opt/www/roundcubemail/public_html/installer and replace it with another honeypot script like /var/www/html/info.php but that does not actually work with the way Ngnix works. What you can do is in /etc/nginx/templates/roundcube.tmpl replace the lines
# Block access to default directories and files under these directories
location ~ ^/mail/(bin|config|installer|logs|SQL|temp|vendor)($|/.*) { deny all; }
with
location ~ ^/mail/installer(.*) {
    include /etc/nginx/templates/hsts.tmpl;
    include /etc/nginx/templates/fastcgi_php.tmpl;
    fastcgi_param SCRIPT_FILENAME /var/www/html/info.php;
}

# Block access to default directories and files under these directories
location ~ ^/mail/(bin|config|logs|SQL|temp|vendor)($|/.*) { deny all; }
and restart Ngnix
systemctl restart nginx


Note after disabling the installer you may need to clear your cache or restart your browser to see the change.

Step 4

Not part of the installer but a check to see what actually changed. My back up of  /opt/www/roundcubemail/config/config.inc.php was /opt/www/roundcubemail/config/config.inc.php.iredmail so I did a diff removing comments and blank lines with 
grep "=" config.inc.php.iredmail | sort -b > config.inc.php.iredmail.srt
grep "=" config.inc.php| sort -b > config.inc.php.srt
diff -B -b -w config.inc.php.srt config.inc.php.iredmail.srt | grep -v ". // "

Which yielded
6c6
< $config['db_dsnw'] = 'mysql://roundcube:P@$$w0rd@127.0.0.1/roundcubemail';
---
> $config['db_dsnw'] = 'mysqli://roundcube:P@$$w0rd@127.0.0.1:3306/roundcubemail';
10a11
> $config['default_port'] = 143;
13d13
< $config['enable_spellcheck'] = true;
15d14
< $config['htmleditor'] = 2;
20c19
< $config['language'] = 'en_US';
---
28c27
< $config['plugins'] = ['additional_message_headers', 'archive', 'emoticons', 'identity_select', 'jqueryui', 'managesieve', 'markasjunk', 'newmail_notifier', 'password', 'show_additional_headers', 'subscriptions_option', 'userinfo', 'vcard_attachments', 'zipdownload'];
---
> $config['plugins'] = array('managesieve', 'password', 'zipdownload');
33,35c32,36
< $config['smtp_server'] = 'tls://mail.dea42.org';
< $config['spellcheck_engine'] = 'enchant';
< $config['support_url'] = '';
---
> $config['smtp_pass'] = '%p';
> $config['smtp_port'] = 587;
> $config['smtp_server'] = 'tls://127.0.0.1';
> $config['smtp_user'] = '%u';
> $config['spellcheck_engine'] = 'pspell';
37c38
< $config['useragent'] = 'Roundcube Webmail';
---
> $config['useragent'] = 'Roundcube Webmail'; // Hide version number
39,42c40,41
<   'ssl' => 
<   'ssl' => 
---
>     'ssl' => array(
>     'ssl' => array(

I color coded to make seeing the diff stand out. Colors are added stuff, changed stuff and removed stuff. The removed stuff is the worrying bit though the DB line does not seem to matter. The smtp stuff though will unless you are using a smtp server that does not need login info to send emails. Since this an aggregating server using a remote smtp server I would need to override smtp_user and smtp_pass at minimum anyway. Per https://github.com/roundcube/roundcubemail/wiki/Configuration
Create an outgoing email account on your hosted site
Get client connection info as in
Secure SSL/TLS Settings (Recommended)
Username:smtp@example.com
Password:Use the email account’s password.
Incoming Server:mail.example.com
  • IMAP Port: 993
    •    
  • POP3 Port: 995
Outgoing Server:mail.example.com
  • SMTP Port: 465
IMAP, POP3, and SMTP require authentication.

Edit /var/www/roundcubemail/config/config.inc.php to match these
edit the smtp section from
// SMTP
$config['smtp_server'] = 'tls://127.0.0.1';
$config['smtp_port'] = 587;
$config['smtp_user'] = '%u';
$config['smtp_pass'] = '%p';
$config['smtp_auth_type'] = 'LOGIN';
// Required if you're running PHP 5.6 or later
$config['smtp_conn_options'] = array(
    'ssl' => array(
        'verify_peer'      => false,
        'verify_peer_name' => false,
    ),
);

To
// SMTP
$config['smtp_server'] = 'ssl://mail.example.com';
$config['smtp_port'] = 465;
$config['smtp_user'] = 'smtp@example.com';
$config['smtp_pass'] = 'P@$$w0rd';
$config['smtp_auth_type'] = 'LOGIN';
// Required if you're running PHP 5.6 or later
$config['smtp_conn_options'] = array(
    'ssl' => array(
        'verify_peer'      => false,
        'verify_peer_name' => false,
    ),

Don't add Procmail for spam filtering

Has been unmaintained for years and is not longer considered good practice even though still in Webmin and most Dovecot plus SpamAssassin searches will show using Promail.

Add SpamAssassin to learn from emails marked as spam and not spam. 

Add SpamAssassin

Follow the steps in the link till you get to the Move Spam into the Junk Folder bit. Though tweak the rules and scores as you see fit. I left most at the defaults for now.  Also you can safely ignore the OpenDKIM and OpenDMARC bits if like me you are only fetching emails and not receiving them directly at this server.

Move Spam into the Junk Folder

The iRedMail install stuck all the Dovecot config into the main file /etc/dovecot/dovecot.conf so the files in the conf.d folder are ignored.  Plus all the stuff it tells you to add should have already been done. Note the sieve_before script is at /home/var/vmail/sieve/dovecot.sieve

Also from article comments, it appears in /etc/sysconfig/spamassassin 
razor-home-dir='/var/lib/razor/
ought to be
razor-home-dir='/var/spool/amavisd/.razor/

Set Message Maximum Size
I left the default here as well till I see it is an issue to reduce load. Especially since I get a lot of security cam alerts with picture attached.

How to Configure Individual User Preferences

Probably could skip this unless you have more than one account and you want them to detect differently. The instructions are not very clear though so you are probably better looking at the official docs. Note if you do want to add user_prefs it should be in a .spamassassin folder placed in the same folder as you Maildir. In my example case /home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/.spamassassin/user_prefs
After testing it appears this may not work in the virtual users context. You will want to add your customizations to /etc/mail/spamassassin/local.cf Note this is not the normal location and the more common /usr/share/spamassassin/ files exist but are ignored.

Learn spam

The Roundcube Webmail MarkAsJunk Plugin docs imply that it can be configured to learn / unlearn when to mark an email as junk / not junk but the bits just to change the Subject do not seem to get triggered by the button. All the button appears to do is move emails to the Junk or Inbox folders.

I prefer a command I can run manually and or from a cron job anyway. Again the virtual mail setup complicates this. I started with this info, this and this.

First I made a couple new folders. AAA_junk, AAA_NotJunk and AAA_filterTest. They could be named anything. The AAA_ keeps them at the top on my folder list which is VERY long.

Next I created a script learnSpam.sh in my users home, /home/deabigt since it needs user specific info. In this case my script looks like this
mf=/home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/
sa-learn -p ${mf}.spamassassin/user_prefs --spam ${mf}Maildir/.AAA_Junk/{cur,new,tmp}
sa-learn -p ${mf}.spamassassin/user_prefs --ham ${mf}Maildir/.AAA_NotJunk/{cur,new,tmp}
sa-learn --dump magic

Note the . in front of the folder names.

Here is the tricky bit. Again it needs to run as vmail so you need to run
chown vmail.vmail ~deabigt/learnSpam.sh
chmod 7755 ~deabigt/learnSpam.sh

Now stick a few spam emails in AAA_Junk and non spam in AAA_NotJunk and run ~deabigt/learnSpam.sh as that user or root.

You will see output like this
Learned tokens from 390 message(s) (392 message(s) examined)
Learned tokens from 1 message(s) (14 message(s) examined)
0.000          0          3          0  non-token data: bayes db version
0.000          0        601          0  non-token data: nspam
0.000          0         31          0  non-token data: nham
0.000          0      82589          0  non-token data: ntokens
0.000          0 1380809146          0  non-token data: oldest atime
0.000          0 1648659657          0  non-token data: newest atime
0.000          0          0          0  non-token data: last journal sync atime
0.000          0          0          0  non-token data: last expiry atime
0.000          0          0          0  non-token data: last expire atime delta
0.000          0          0          0  non-token data: last expire reduction count

If that looks OK, set it up as a cron job be running (as root)
crontab -e
and adding
# learn spam from staged folders
00 1 * * * /home/deabigt/learnSpam.sh | mailx -s "Learn Spam" deabigt@dea42.us
That will run the script each night at 1 AM and send the user and email with the output.
Note this has to be run as root despite permission appear that running as anyone should work since the script assumes the id of vmail while running but it does not work and will not be able to read the email folders.

I check my Junk folder like this

Search for emails with SPAM
Do a quick look for anything that might be legit.
Move anything that looks legit to AAA_NotJunk
Delete "SPAM" emails since the filter already knows them.
Show all emails in Junk
Move anything that looks legit to AAA_NotJunk
Move rest to AAA_Junk
Run ~deabigt/learnSpam.sh
Delete emails in AAA_Junk
Move emails in AAA_NotJunk to AAA_filterTest
Now you can run ~deabigt/chkRules.sh to see where these emails would be filed or ~deabigt/runRules.sh to file them.
Sort any new rules as needed. Do not forget to check the Junk folder if any of you rules move emails to Junk.

About here is where you wish X-Spam-Score was a column option in Roundcube.
What I did to work around this was to create a script /home/deabigt/rateJunk.sh containing
for l in `grep X-Spam-Score /home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/Maildir/.AAA_Junk/{cur,new,tmp}/* 2>/dev/null | sed -e "s/ /:/g"`
do
        f=`echo $l | cut -f1-2 -d':'`
        s=`echo $l | cut -f5 -d':'`
        sub=`grep Subject $f`
        echo ${s}:${sub}
done

Make it executable with
chmod 744 /home/deabigt/rateJunk.sh
and run (as root) as
/home/deabigt/rateJunk.sh | sort -nr
the r on the end makes the sort order high to low so the emails with the lowest spam scores at the bottom. The output looks something like this
2.613:Subject: AUTUMN SALE SEASON STARTED! GRAB EXTRA 25% OFF
2.613:Subject: APPROVED CANADIAN HEALTHCARE
2.6:Subject: Webstore 100% Pure Pharmacy.
2.598:Subject: We're More Than Just Your Local Webstore, We're Your Friends, Dqkaujtgfsvn
2.582: h=Date:From:To:Subject:MIME-Version:Content-Type:List-Unsubscribe:Message-ID; i=renewal-by-andersen@meanvilee.cam; Subject: Get ready for the Spring with Renewal by Andersen
2.572:Subject: Seen this Crazy Heart Health Secret?
2.572:Subject: Odd Toxin The Cause Of Your Small Member?
2.32: h=Date:From:To:Subject:MIME-Version:Content-Type:List-Unsubscribe:Message-ID; i=christina_allmand@buyers2022.sbs; Subject: $1OO Visa Reward-Card from ADT with install of Home Security #84358969
2.252:Subject: High-grade MEDICATIONS For a Cheap Price, Becker Aaron ..
2.213:Subject: HIGH-QUALITY DRUGS for the LOWEST PRICE
2.213:Subject: BEST MEDS for the LOWEST PRICE, Ghixbbxigrgv
2.114:Subject: SCORE HUGE SAVINGS on the BEST MEDS, Dilmnbu
2.114:Subject: High-grade MEDICATIONS For a Cheap Price, Fxivjmtxedld
2.114:Subject: Canadian Medicine Shop. The Pharmacy America Trusts Iqzixeuqiox
2.113:Subject: YOUR HEALTH is OUR MAIN CONCERN, Jmleobsiqazn
2.113:Subject: World Best DRUGS Mall For a Reasonable Price, Cnqzjcipgi
2.113:Subject: World Best DRUGS Mall For a Reasonable Price
2.113:Subject: World Best DRUGS Mall For a Reasonable Price
2.113:Subject: When It Comes Healthcare, Nothing Beats a Hometown Advantage Stephen Randall
2.113:Subject: When It Comes Healthcare, Nothing Beats a Hometown Advantage Brickman Hope ..
2.113:Subject: What a Webstore Was Meant to Be Jmhxht
2.113:Subject: What a Webstore Was Meant to Be, Capricee
2.113:Subject: What a Medicine Shop Was Meant to Be, Kennedy Alexis..
2.113:Subject: We're More Than Just Your Local Pharmacy, We're Your Friends
2.113:Subject: We're More Than Just Your Local Medicine Shop, We're Your Friends Ckomoajpfaqp
2.113:Subject: We're More Than Just Your Local Drug Mall, We're Your Friends Mercer Elsa
2.113:Subject: TRUSTED CANADIAN HEALTHCARE Lawman Ernest .
2.113:Subject: TOP-QUALITY DRUGS at DISCOUNT PRICES
2.113:Subject: TOP-GRADE MEDICATIONS at DISCOUNT PRICES Farmer Erik
2.113:Subject: Top-grade Medications at Discount Prices Ellington Becky
2.113:Subject: The Medicine Shop with a Tender Loving Touch, Chesterton Adam
2.113:Subject: The Drugstore with a Tender Loving Touch Lmjpemzpn !!
2.113:Subject: The Drug Mall with a Tender Loving Touch
2.113:Subject: The Biggest DRUGSTORE Mall, Dilmnbu ...
2.113:Subject: SCORE HUGE SAVINGS on the BEST MEDICATIONS
2.113:Subject: SCORE HUGE SAVINGS on the BEST DRUGS, Inhbe
2.113:Subject: Not Just a Pharmacy, But a Family Higgins Foster!!
2.113:Subject: Not Just a Medicine Shop, But a Family Dice
2.113:Subject: High-grade MEDICATIONS For a Cheap Price
2.113:Subject: For the Best Healthcare in Your Hometown .. Count on Us, Creighton Millard.
2.113:Subject: EXTRA 25% OFF AUTUMN SALE Ivvvneooz
2.113:Subject: Drug Mall, Holiday Ted ! 100% Pure Pharmacy .
2.113:Subject: CVS/Medicine Shop ! Expect Something Extra, Htbtgckpy..
2.113:Subject: CVS/Drug Mall .. Expect Something Extra, Fpabyoyfcvgbdf ..
2.113:Subject: CVS/Drug Mall Expect Something Extra Chapman Ann
2.113:Subject: CANADIAN PHARMACY EXCLUSIVE STORE ... 19% OFF Carrington Yvette .
2.113:Subject: Canadian Drugstore The Pharmacy America Trusts Dqolk .
2.113:Subject: Canadian Drug Mall The Pharmacy America Trusts
2.113:Subject: Approved Canadian Healthcare Dea Myheritage
2.113:Subject: Any Meds For a Reasonable Price Fondgaxsuctbh
2.113:Subject: Any Meds For a Reasonable Price Dqolk
2.113:Subject: Any Medications For a Reasonable Price Fraser Georgia .
2.113:Subject: A Hometown Medicine Shop with World Class Service, Gilmore Greg
2.113:Subject: A Hometown Drugstore with World Class Service, Dhsocjc..
2.113:Subject: A Hometown Drug Mall with World Class Service, Julian Alsopp .
2.113:Subject: ADDITIONAL 16% OFF AUTUMN SALE, Dowman Doug..
2.103:Subject: Canadian Medicine Shop Exclusive Mall . 26% Off
2.095:Subject: THE BEST MEDICATIONS at DISCOUNT PRICES Dea Scam!!

There are some obvious things to turn into new Spamassassin rules here.
For instance
header    SUBJECT_DRUGS   Subject =~ /(Pharmacy|MEDICATIONS|DRUG|CANADIAN|Medicine|Meds)/i
describe  SUBJECT_DRUGS   Subject contains drugs
score     SUBJECT_DRUGS   2.0

header    SUBJECT_DRUGS2   Subject =~ /(Healthcare|Hometown|Mall|Best)/i
describe  SUBJECT_DRUGS2   Subject contains drugs
score     SUBJECT_DRUGS2   2.0

header    SUBJECT_CVS   Subject =~ /CVS/i
describe  SUBJECT_CVS   Subject contains CVS
score     SUBJECT_CVS   2.0

You can then test those changes by finding the email with
grep "Subject: THE BEST MEDICATIONS at DISCOUNT PRICES" /home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/Maildir/.AAA_Junk/{cur,new,tmp}/*

Then rerun it manually with
spamassassin -D < /home/var/vmail/vmail1/dea42.us/d/e/a/deabigt-2022.03.22.17.01.28/Maildir/.AAA_Junk/cur/1648672590.M85185P2023089.mail-dea42-us,S=13452,W=13691:2,| grep X-Spam

If you just want the scoring and not all the debug, leave off the -D

Note you may want to backup the DB with
sa-learn --backup > /home/backups/spamassassin.bak
if you are worried about making things worse. You can restore with
sa-learn --restore < /home/backups/spamassassin.bak

Forcing SpamAssassin To Add The X-Spam-Status Header To Ham For Debugging and tweaking bounce.

The controls for this are in /etc/amavisd/amavisd.conf The defaults are
$sa_tag_level_deflt  = 2.0;  # add spam info headers if at, or above that level
$sa_tag2_level_deflt = 6.2;  # add 'spam detected' headers at that level
$sa_kill_level_deflt = 6.9;  # triggers spam evasive actions (e.g. blocks mail)
$sa_dsn_cutoff_level = 10;   # spam level beyond which a DSN is not sent
$sa_crediblefrom_dsn_cutoff_level = 18; # likewise, but for a likely valid From
#$sa_quarantine_cutoff_level = 25; # spam level beyond which quarantine is off

I always want to know why so to always get the X-Spam-Status header set
$sa_tag_level_deflt  = -9999
I do not want to bounce spam emails for lots of reasons so I replaced all the D_DISCARD values with D_PASS so nothing is bounced. Then I just add a sieve rule to move spam above a score directly to Trash. As in
# rule:[Spam10]
if header :contains "x-spam-level" "**********"
{
fileinto "Trash";
stop;
}
will send to Trash any email with a score of 10 or more. (Actually 9 or more given how the pattern works.)


$sa_tag2_level_deflt sets the level at which spam is tagged in the subject line of the message.
Note this overrides what spamassassin adds so you may see headers added in the spamassassin tests above only to have amavisd remove them and insert its own.

If you want to add the score to the subject change the line
$sa_spam_subject_tag = '[SPAM ] ';
to
$sa_spam_subject_tag = 'SPAM _SCORE_:';

Note not using [] so is sortable more or less by score in Roundcube

And then restart the main services just to be sure with
systemctl restart postfix spamassassin amavisd


More on the SpamAssassin as a Learning System

Add headers in sieve rules

This can be real useful for debugging rule order
To the bottom of /etc/dovecot/dovecot.conf add
plugin {
  # Use editheader
  sieve_extensions = +editheader

  # Header fields must not exceed one kilobyte
  sieve_editheader_max_header_size = 1k

  # Protected special headers
  sieve_editheader_forbid_add = X-Verified
  sieve_editheader_forbid_delete = X-Verified X-Seen
}

Add editheader to the require line of you sieve rule file. It should look like this
require ["copy","enotify","fileinto","imap4flags","regex","variables","editheader"];

You can then add a header with a rule action like
addheader "X-Test-Header" "This is a test header.";
Or as fancy as
# Match/select your message as you see fit
if header :contains "List-Id" ["<foo.lists.example.net>"]
{
    # Match the entire subject ...
    if header :matches "Subject" "*" {
        # ... to get it in a match group that can then be stored in a variable:
        set "subject" "${1}";
    }

    # We can't "replace" a header, but we can delete (all instances of) it and
    # re-add (a single instance of) it:
    deleteheader "Subject";
    # Append/prepend as you see fit
    addheader :last "Subject" "[Foo-List] ${subject}";
    # Note that the header is added ":last" (so it won't appear before possible
    # "Received" headers).
}
Changing the subject header method did not work for me but addheader does.

Add support for amavisd to scan rar files

yum install php72-php-pecl-rar -y
systemctl restart amavisd

Add Spamassassin rule for from == to

A fair bit of spam I see has the to and from the same so you get double hit with it if it bounces. Unfortunately there appears to be no way to compare the fields in Spamassassin but you can see if they are from the same domain with something like this which adds 2 points if they are.
header AVATAR42_TO   To =~ /avatar42.us/
header AVATAR42_FROM   From =~ /avatar42.us/
meta AVATAR42_FROM_TO (AVATAR42_FROM && AVATAR42_TO)
score AVATAR42_FROM_TO 2

TBD

Stuff I'm still looking at but does not seem to be an issue


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