6.3 KiB
About Virtual Vacation
AKA 'An out of office' automated email response.
The vacation script runs as service within Postfix's master.cf configuration file. Mail is sent to the vacation service via a transport table mapping. When users mark themselves as away on vacation, an alias is added to their account sending a copy of all mail to them to the vacation service.
e.g. mail to billy@goat.com will be delivered to
Mail to @autoreply.goat.com is caught by the vacation.pl script and a reply will be sent based on various settings. By default a reply is only sent once.
Dependencies / Requirements
There are a bunch of Perl modules which need installing, depending on your distribution these may be available through your package management tool, or will need installing through CPAN.
Email::Valid
Email::Sender
Email::Simple
Email::Valid
Try::Tiny
MIME::Charset
MIME::EncWords
Log::Log4perl
Log::Dispatch
GetOpt::Std
You may install these via CPAN, or through your package tool.
CPAN: 'perl -MCPAN -e shell', then 'install Module::Whatever'
Debian Systems
apt-get install libemail-sender-perl libemail-simple-perl libemail-valid-perl libtry-tiny-perl libdbd-pg-perl libmime-perl liblog-log4perl-perl liblog-dispatch-perl libgetopt-argvfile-perl libmime-charset-perl libmime-encwords-perl libmime-encwords-perl
and one of :
libdbd-pg-perl or libdbd-mysql-perl
Installing Virtual Vacation
1. Create a local account
Create a dedicated local user account called "vacation". This user handles all potentially dangerous mail content - that is why it should be a separate account.
Do not use "nobody", and most certainly do not use "root" or "postfix". The user will never log in, and can be given a "*" password and non-existent shell and home directory.
Also create a separate "vacation" group.
This should look like this:
#/etc/passwd
vacation:*:65501:65501:Virtual Vacation:/nonexistent:/sbin/nologin
#/etc/group
vacation:*:65501:
2. Create a log directory or log file
If you want to log to a file ($log_to_file), create a log directory or an empty log file.
This file or directory needs to be writeable for the "vacation" user.
Note: If you are logging to syslog, you can skip this step.
3. Install vacation.pl
Create a directory /usr/lib/postfixadmin/ and copy the vacation.pl file to it:
mkdir /usr/lib/postfixadmin
cp vacation.pl /usr/lib/postfixadmin/vacation.pl
chown -R root:vacation /usr/lib/postfixadmin
chmod 750 /usr/lib/postfixadmin/ /usr/lib/postfixadmin/vacation.pl
Which will then look something like:
-rwxr-x--- 1 root vacation 3356 Dec 21 00:00 vacation.pl*
4. Setup the transport type
Define the transport type in the Postfix master file:
#/etc/postfix/master.cf:
vacation unix - n n - - pipe
flags=Rq user=vacation argv=/usr/lib/postfixadmin/vacation.pl -f ${sender} -- ${recipient}
5. Setup the transport maps file
Tell Postfix to use a transport maps file, so add the following to your Postfix main.cf:
#/etc/postfix/main.cf:
transport_maps = hash:/etc/postfix/transport
Then add the transport definition to the newly created transport file. Obviously, change yourdomain.com to your own domain. This can be any arbitrary domain, and it is easiest if you just choose one that will be used for all your domains.
#/etc/postfix/transport
autoreply.yourdomain.com vacation:
(You may need to create an entry in /etc/hosts for your non-existant domain)
Execute
postmap /etc/postfix/transport
Execute
postfix reload
to complete the change.
6. Configure vacation.pl
The perl vacation.pl script needs to know which database you are using, and also how to connect to the database.
Namely :
Change any variables starting with '$db_' and '$db_type' to either 'mysql' or 'pgsql'.
Change the $vacation_domain variable to match what you entered in your /etc/postfix/transport file.
You can do this in two ways:
a) edit vacation.pl directly (not recommended!)
b) create /etc/postfixadmin/vacation.conf and enter your settings there
Just use perl syntax there to fill the config variables listed in vacation.pl (without the "our" keyword). Example:
$db_username = 'mail';
To make sure nobody except vacation.pl can read your vacation.conf (including the database password), run
chown root:vacation /etc/postfixadmin/vacation.conf
chmod 640 /etc/postfixadmin/vacation.conf
7. Check the alias expansion
Depending on your setup, you may have multiple 'smtpd' service definitions within your postfix master.cf file. This is especially the case if you are also using AMAVIS or another content filtering system when mail is re-injected into Postfix using the smtpd daemon.
If you are, it's likely that alias expansion may happen more than once, in which case you may see vacation-style responses duplicated. To suppress this behaviour, you need to add:
-o receive_override_options=no_address_mappings
For example :
smtp inet n - - - 12 smtpd
-o content_filter=amavis:[127.0.0.50]:10024
-o receive_override_options=no_address_mappings
127.0.0.1:10025 inet n - - - - smtpd
-o smtpd_autorized_xforward_hosts=127.0.0.0/8
-o smtpd_client_restrictions=
-o smtpd_helo_restrictions=
-o smtpd_sender_restrictions=
-o smtpd_recipient_restrictions=permit_mynetworks,reject
-o mynetworks=127.0.0.0/8
-o receive_override_options=no_header_body_checks
^^^ Alias expansion occurs here, so we don't want it to happen again for the
first smtpd daemon (above). If you have per-user settings in amavis,
you might want to have no_address_mappings in the smtpd on port 10025
instead.
8. Security
If security is an issue for you, read ../DOCUMENTS/Security.txt
Postfixadmin
When this is all in place you need to have a look at the Postfix Admin config.inc.php. Here you need to enable Virtual Vacation for the site.
Help ! It's not working
When something is not working there are a couple of files that you can have a look at. The most important one is your maillog (usually in /var/log/).
Vacation.pl also has some debugging and logging capabilties. Check the top of vacation.pl.