Difference between revisions of "Virtual user mail system"
(→Fire it up: Changing for updates to courier-imap) |
(→Postfix: Adding info about submission/smtps) |
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=== Postfix === | === Postfix === | ||
| − | + | There are basically 2 ways for of doing SMTPS. | |
| + | |||
| + | One is using the wrapper mode which enables even old/odd clients like Outlook to use TLS. The wrapper mode use the system service "smtps" which is a non-standard service and runs on port 465. | ||
| + | |||
| + | The other, more proper method is to use a port that simply enforces TLS without any wrapping. The system service for this is "submission" which is standard and uses port 587. | ||
| + | |||
| + | For the improper variant uncomment this in {{filename|/etc/postfix/master.cf}}: | ||
smtps inet n - n - - smtpd | smtps inet n - n - - smtpd | ||
-o smtpd_tls_wrappermode=yes | -o smtpd_tls_wrappermode=yes | ||
| + | -o smtpd_sasl_auth_enable=yes | ||
| + | |||
| + | For the proper variant uncomment this in {{filename|/etc/postfix/master.cf}}: | ||
| + | submission inet n - n - - smtpd | ||
| + | -o smtpd_tls_security_level=encrypt | ||
-o smtpd_sasl_auth_enable=yes | -o smtpd_sasl_auth_enable=yes | ||
Revision as of 11:53, 15 July 2011
This article describes how to set up a complete virtual user mail system on an Arch Linux system in the simplest manner possible. However, since a mail system consists of many complex components, quite a bit of configuration will still be necessary. Roughly, the components used in this article are Postfix, Cyrus, Courier, PAM, PostfixAdmin and Roundcube.
In the end, the provided solution will allow you to use the best currently available security mechanisms, you will be able to send mails using SMTP and SMTPS and receive mails using POP3, POP3S, IMAP and IMAPS. Additionally, configuration will be easy thanks to PostfixAdmin and users will be able to login using Roundcube. What a deal!
This article assumes that you have a working LAMP setup as we will need a working Apache2 as well as MYSQL database. Of course, with a few changes to these instructions you could easily use another httpd and database. For the purposes of this tutorial, however, the choice made above will be used. Additionally, the article assumes all-default settings for every package installed below. No changes except for those mentioned will be required.
Should any unforeseen problems occur, feel free to use the discussion page to voice your problems and I will try to answer.
Contents
Installation
# pacman -S postfix courier-imap cyrus-sasl cyrus-sasl-plugins pam_mysql
Configuration
User
For security reasons, a new user should be created to store the mails:
groupadd -g 5000 vmail useradd -u 5000 -g vmail -s /sbin/nologin -d /home/vmail -m vmail
A gid and uid of 5000 is used in both cases so that we do not run into conflicts with regular users. All your mail will then be stored in /home/vmail. You could change the home dir to something like /var/mail/vmail but careful to change this in any configuration below as well.
Database
You will need to create an empty database and corresponding user. We will be using PostfixAdmin's tables to fill the database later on. In this article, postfix_user will have read/write access to postfix_db using hunter2 for a password. You are expected to create your database and user yourself. Make sure to assign proper permissions.
Postfix
There are basically 2 ways for of doing SMTPS.
One is using the wrapper mode which enables even old/odd clients like Outlook to use TLS. The wrapper mode use the system service "smtps" which is a non-standard service and runs on port 465.
The other, more proper method is to use a port that simply enforces TLS without any wrapping. The system service for this is "submission" which is standard and uses port 587.
For the improper variant uncomment this in Template:Filename:
smtps inet n - n - - smtpd -o smtpd_tls_wrappermode=yes -o smtpd_sasl_auth_enable=yes
For the proper variant uncomment this in Template:Filename:
submission inet n - n - - smtpd -o smtpd_tls_security_level=encrypt -o smtpd_sasl_auth_enable=yes
To Template:Filename append:
relay_domains = * virtual_alias_maps = proxy:mysql:/etc/postfix/virtual_alias_maps.cf virtual_mailbox_domains = proxy:mysql:/etc/postfix/virtual_domains_maps.cf virtual_mailbox_maps = proxy:mysql:/etc/postfix/virtual_mailbox_maps.cf virtual_mailbox_base = /home/vmail virtual_mailbox_limit = 512000000 virtual_minimum_uid = 5000 virtual_transport = virtual virtual_uid_maps = static:5000 virtual_gid_maps = static:5000 local_transport = virtual local_recipient_maps = $virtual_mailbox_maps transport_maps = hash:/etc/postfix/transport smtpd_sasl_auth_enable = yes smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination smtpd_sasl_security_options = noanonymous smtpd_sasl_tls_security_options = $smtpd_sasl_security_options smtpd_tls_auth_only = yes smtpd_tls_cert_file = /etc/ssl/certs/server.crt smtpd_tls_key_file = /etc/ssl/private/server.key smtpd_sasl_local_domain = $mydomain broken_sasl_auth_clients = yes smtpd_tls_loglevel = 1
This references a lot of files that don't even exist yet. Let's create them.
Edit Template:Filename as new and add:
user = postfix_user password = hunter2 hosts = localhost dbname = postfix_db query = SELECT goto FROM alias WHERE address='%s' AND active = true
Edit Template:Filename as new and add:
user = postfix_user password = hunter2 hosts = localhost dbname = postfix_db query = SELECT domain FROM domain WHERE domain='%s' and backupmx = false and active = true
Edit Template:Filename as new and add:
user = postfix_user password = hunter2 hosts = localhost dbname = postfix_db query = SELECT quota FROM mailbox WHERE username='%s'
Edit Template:Filename as new and add:
user = postfix_user password = hunter2 hosts = localhost dbname = postfix_db query = SELECT maildir FROM mailbox WHERE username='%s' AND active = true
Run postmap on transport to generate its db:
postmap /etc/postfix/transport
We still need the SSL cert and private key:
cd /etc/ssl/certs openssl req -new -x509 -newkey rsa:1024 -days 365 -keyout server.key -out server.crt openssl rsa -in server.key -out server.key chown nobody:nobody server.key chmod 600 server.key mv server.key /etc/ssl/private/
Courier
In Template:Filename make sure that authmodulelist only contains authmysql:
authmodulelist="authmysql"
Next, we need to configure the field names used by PostfixAdmin in Template:Filename. Search and replace values provided here. Uncomment commented entries if necessary:
MYSQL_HOST localhost MYSQL_PORT 3306 MYSQL_USERNAME postfix_user MYSQL_PASSWORD hunter2 MYSQL_DATABASE postfix_db MYSQL_USER_TABLE mailbox MYSQL_CRYPT_PWFIELD password MYSQL_UID_FIELD 5000 MYSQL_GID_FIELD 5000 MYSQL_LOGIN_FIELD username MYSQL_HOME_FIELD "/home/vmail" MYSQL_NAME_FIELD name MYSQL_MAILDIR_FIELD maildir MYSQL_QUOTA_FIELD quota
Edit the [ reg_dn ] part in Template:Filename and Template:Filename to correctly state your mail server's location. E.g.:
[ req_dn ] C=DE ST=Hamburg L=Hamburg O=Courier Mail Server OU=Automatically-generated IMAP SSL key CN=localhost emailAddress=god@world.com
Next, generate the certificates and move them into position:
mkimapdcert mv /usr/share/imapd.pem /etc/courier-imap/ mkpop3dcert mv /usr/share/pop3d.pem /etc/courier-imap/
Cyrus
Firstly, edit Template:Filename and add
smtps 465/tcp # Secure Simple Mail Transfer smtps 465/udp # Secure Simple Mail Transfer
to it.
Contents of Template:Filename should be:
auth required /lib/security/pam_mysql.so user=postfix_user passwd=hunter2 host=localhost db=postfix_db table=mailbox usercolumn=username passwdcolumn=password crypt=1 account sufficient /lib/security/pam_mysql.so user=postfix_user passwd=hunter2 host=localhost db=postfix_db table=mailbox usercolumn=username passwdcolumn=password crypt=1
Modify Template:Filename to say:
SASLAUTHD_OPTS="-m /var/run/saslauthd -r -a pam"
Finally, Template:Filename should have:
pwcheck_method: saslauthd mech_list: plain login saslauthd_path: /var/run/saslauthd/mux log_level: 7
PostfixAdmin
To install PostfixAdmin, we need to manually get its upstream package and extract it to our web root (or other desired directory). You should use the most recent version available at the time. This article will use the most recent version at the time of writing.
cd /srv/http/ wget http://sourceforge.net/projects/postfixadmin/files/postfixadmin/postfixadmin-2.3.2/postfixadmin-2.3.2.tar.gz/download tar xzf postfixadmin-2.3.2.tar.gz cd postfixadmin-2.3.2
Next, PostfixAdmin needs to be configured. Assuming localhost is the hostname of the machine you are installing this on, navigate to http://localhost/postfixadmin-2.3.2/setup.php. The setup will guide you through the remaining steps to set up PostfixAdmin.
Roundcube
As with PostfixAdmin, this article will use the most recent version as of the time of writing. You should always use the most recent version available.
cd /srv/http/ wget http://sourceforge.net/projects/roundcubemail/files/roundcubemail/0.4/roundcubemail-0.4.tar.gz/download tar xzf roundcubemail-0.4.tar.gz cd roundcubemail-0.4
Make some directories writable by the webserver:
chown -R http:http temp logs
Assuming that localhost is your current host, navigate a browser to http://localhost/roundcubemail-0.4/installer/ and follow the instructions. You could use the same database for Roundcube that you already used for PostfixAdmin though you shouldn't. For a proper setup, create a second database "roundcube_db" and a "roundcube_user" for use with Roundcube.
While running the installer, make sure to address the IMAP host with tls://localhost/ instead of just localhost. Use port 993. Likewise with SMTP, make sure to provide ssl://localhost/ on port 465.
rc.conf
The services should be restarted in the correct order on system restart. Make sure your DAEMONS array in Template:Filename contains:
DAEMONS=( ... fam saslauthd postfix authdaemond imapd imapd-ssl pop3d pop3d-ssl ... )
Make sure to keep this order.
Fire it up
Since now hopefully everything is set up correctly, all necessary daemons should be started for a test run:
for daemon in fam saslauthd postfix authdaemond imapd imapd-ssl pop3d pop3d-ssl; do /etc/rc.d/$daemon start; done
The order in which the daemons are started up is actually important here.
As a final bit of configuration, Postfix needs to be able to write to saslauth. Thus:
chown postfix:postfix /var/run/saslauthd
Now for testing purposes, create a domain and mail account in PostfixAdmin. Try to login to this account using Roundcube. Now send yourself a mail.