Install

The Horde project provide a very complete groupware, divided in many software projects. These softwares are available either alone, either in the bundle  Horde Groupware Webmail Edition. This guide help you to install this bundle. First, we install the needed software packages :

/usr/bin/apt-get install libapache2-mod-php5 php5-gd php5-mysql php5-mcrypt php5-imap php5-tidy php5-cli php-pear

In order for Horde to work flawlessly, we rise the memory limit of the Apache 2 PHP module :

/bin/sed -i -e 's/memory_limit = .*/memory_limit = 128M/' /etc/php5/apache2/php.ini

You can also enhance Horde performances by installing memcached :

apt-get install memcached php5-memcache

We upgrade the PEAR install :

/usr/bin/pear upgrade-all

We now install PEAR and PECL extensions recommended by Horde. First, we install the packages needed in order to build the extensions :

/usr/bin/apt-get install libmagic-dev libgeoip-dev make php5-dev

And we build and install the PECL extensions :

• fileinfo :
  This extension allow to enhance attached files management.
  

  /usr/bin/pecl install fileinfo
  /bin/echo "extension=fileinfo.so" | /usr/bin/tee /etc/php5/conf.d/fileinfo.ini

• lzf :
  This extension allow to reduce the size of sessions (and so the server memory usage).
  

  /usr/bin/pecl install lzf
  /bin/echo "extension=lzf.so" | /usr/bin/tee /etc/php5/conf.d/lzf.ini
  

• geoip :
  This extension enhance the geolocation of IP addresses. But, due to version incompatibility, it is not simple to install it on Etch.
• idn :
  This extension allow to use internationalized domain names. But, for now on, this extension is still Beta.
  

We set the last version number of Horde Groupware Webmail Edition that we are willing to install :

VERSION=1.0.3

Note : To install the 1.1 RC version of Horde, with AJAX and SyncML support :

VERSION=1.1-rc1

We download Horde Groupware Webmail Edition :

/usr/bin/wget http://ftp.horde.org/pub/horde-webmail/horde-webmail-$VERSION.tar.gz \
    --output-document=/tmp/horde-webmail-$VERSION.tar.gz

We untar the downloaded file :

/bin/tar --directory /var/www -xzf /tmp/horde-webmail-$VERSION.tar.gz

We rename the created folder :

/bin/mv /var/www/horde-webmail-$VERSION /var/www/horde-webmail

We can now configure this software.

Horde configuration

Note : Horde need a database. If you want you can install a MySQL server, or create a database on such a server by following my article MySQL for Debian 4.0 Etch.

The Horde configuration is quite complex because of the bunch of parameters. I encourage you to read the Horde documentation in order for your system to be configured exactly to you needs. This guide only help you to create a working but basic Horde configuration. In order to do this, we use the script provided by Horde :

/usr/bin/php /var/www/horde-webmail/scripts/setup.php

Answer to the questions of this script.

Note : If your IMAP server is not on the server where is installed Horde, you need to edit the IMP configuration :

/usr/bin/vim /var/www/horde-webmail/imp/config/servers.php

Once the configuration done, you can check that nothing is missing by visiting :

• http://localhost/horde-webmail/test.php
  

Note : Don't worry about the memory limit error. 128 MB should be sufficient.

Default email domain

We now set the contact email used when a user encounter problems. We also set the default domain for users' email adresses, when Horde can not detect it :

/bin/sed -i -e "s/^\(.*problems.*email.*=\).*;/\1 'contact@votre-domaine.com';/" /var/www/horde-webmail/config/conf.php
/bin/sed -i -e "s/^\(.*problems.*maildomain.*=\).*;/\1 'votre-domaine.com';/" /var/www/horde-webmail/config/conf.php

Log file

We change the location of Horde log file :

touch /var/log/horde.log
/bin/chown www-data:www-data /var/log/horde.log
/bin/chmod 0640 /var/log/horde.log
/bin/sed -i -e 's/\/tmp\/horde\.log/\/var\/log\/horde\.log/' /var/www/horde-webmail/config/conf.php

And we setup the log rotation for this log file :

/bin/cp /var/www/horde-webmail/scripts/horde.logrotate /etc/logrotate.d/horde

Memory caching

First, be sure that the memory cache is installed :

apt-get install memcached php5-memcache
/etc/init.d/apache2 restart

We enable the memory cache support in Horde :

/bin/sed -i -e 's/^\(.*memcache.*enabled.*=\).*;/\1 true;/' /var/www/horde-webmail/config/conf.php

And we set it up :

/bin/sed -i -e "/^\(.*conf.*memcache.*enabled.*=\).*/i\
\$conf['memcache']['hostspec'] = array('localhost');\n\
\$conf['memcache']['port'] = array('11211');\n\
\$conf['memcache']['weight'] = array();\n\
\$conf['memcache']['persistent'] = false;\n\
\$conf['memcache']['compression'] = false;\n\
\$conf['memcache']['large_items'] = true;" /var/www/horde-webmail/config/conf.php

Cache location

We create a secure cache folder for Horde :

/bin/mkdir /var/cache/horde
/bin/chown www-data:root /var/cache/horde
/bin/chmod 0700 /var/cache/horde

We set up Horde so that it use this folder for its cache files :

/bin/sed -i -e "/^\(.*conf.*umask.*=\).*/a\
\$conf['tmpdir'] = '/var/cache/horde';" /var/www/horde-webmail/config/conf.php

We configure the regular clean up of generated cache files :

/bin/cp /var/www/horde-webmail/scripts/temp-cleanup.cron /etc/cron.daily/horde-temp-cleanup
/bin/chmod +x /etc/cron.daily/horde-temp-cleanup
/bin/sed -i -e 's/^\(TMP_DIR=\).*/\1\/var\/cache\/horde/' /etc/cron.daily/horde-temp-cleanup

Sending alert emails

We now configure Horde to send alert emails :

/bin/echo "# /etc/cron.d/horde : crontab fragment for horde
# Horde Alarms
*/5 * * * * /usr/bin/php /var/www/horde-webmail/scripts/alarms.php" \
    | /usr/bin/tee /etc/cron.d/horde

Sessions monitoring tool

If you want to monitor the Horde sessions, run the following command line :

/bin/chown www-data /var/lib/php5

Warning : This can be a security risk, so I don't recommend this.

Attached files management

If you want to be able to preview your attached files in Horde without download them, here is the command line allowing you to install needed softwares :

/usr/bin/apt-get install unrtf libwpd-tools xlhtml source-highlight ppthtml rpm wv enscript

Once this done, we correct the paths to theses softwares in Horde configuration :

sed -i -e 's/\/usr\/local\/bin\/xlhtml/\/usr\/bin\/xlhtml/' \
       -e 's/\/usr\/local\/bin\/ppthtml/\/usr\/bin\/ppthtml/' \
    /var/www/horde-webmail/config/mime_drivers.php

And we enable the use of the installed tools in Horde :

sed -i -e "s/\/\/ \('deb'\)/\1/g" \
       -e "s/\/\/ \('enscript'\)/\1/g" \
       -e "s/\/\/ \('msword'\)/\1/g" \
       -e "s/\/\/ \('msexcel'\)/\1/g" \
       -e "s/\/\/ \('mspowerpoint'\)/\1/g" \
       -e "s/\/\/ \('rpm'\)/\1/g" \
       -e "s/\/\/ \('rtf'\)/\1/g" \
       -e "s/\/\/ \('srchighlite'\)/\1/g" \
       -e "s/\/\/ \('webcpp'\)/\1/g" \
       -e "s/\/\/ \('wordperfect'\)/\1/g" \
    /var/www/horde-webmail/config/mime_drivers.php

Now, we tell Horde where to find the MIME database :

/bin/sed -i -e "/^\(.*conf.*sessionhandler.*type.*=\).*/a\
\$conf['mime']['magic_db'] = '/usr/share/file/magic';" /var/www/horde-webmail/config/conf.php

IMP configuration

In order to enhance the mail reading experience, we change the default IMP configuration :

Inline HTML mails

By default, you need to download the mails written in HTML. This is not very easy. These command lines modify this behaviour :

/bin/sed -i -e '/.*mime_drivers.*imp.*html.*=.*array.*/{n;d}' /var/www/horde-webmail/imp/config/mime_drivers.php
/bin/sed -i -e "/.*mime_drivers.*imp.*html.*=.*array.*/a\
    'inline' => true," /var/www/horde-webmail/imp/config/mime_drivers.php

Adapting to Mozilla Thunderbird defaults

If your users use Mozilla Thunderbird, you should change the Horde default folders to the one used by Mozilla Thunderbird :

• Sent mails folder :
  

  /bin/sed -i -e "s/^\(.*'value' =>\).*'sent-mail',/\1 'Sent',/" /var/www/horde-webmail/imp/config/prefs.php

• Drafts folder :
  

  /bin/sed -i -e "s/^\(.*'value' =>\).*'drafts',/\1 'Drafts',/" /var/www/horde-webmail/imp/config/prefs.php

• Trash folder :
  

  /bin/sed -i -e "s/^\(.*'value' =>\).*'trash',/\1 'Trash',/" /var/www/horde-webmail/imp/config/prefs.php

• Junk mail folder :
  

  /bin/sed -i -e "s/^\(.*'value' =>\).*'Spam',/\1 'Junk',/" /var/www/horde-webmail/imp/config/prefs.php

Adapting to Outlook defaults

The following command lines are for a french Outlook, but you can change them to fit your needs :

• Sent mails folder :
  

  /bin/sed -i -e "s/^\(.*'value' =>\).*'sent-mail',/\1 '&AMk-l&AOk-ments envoy&AOk-s',/" /var/www/horde-webmail/imp/config/prefs.php

• Drafts folder :
  

  /bin/sed -i -e "s/^\(.*'value' =>\).*'drafts',/\1 'Brouillons',/" /var/www/horde-webmail/imp/config/prefs.php

• Trash folder :

  /bin/sed -i -e "s/^\(.*'value' =>\).*'trash',/\1 '&AMk-l&AOk-ments supprim&AOk-s',/" /var/www/horde-webmail/imp/config/prefs.php

Attached files preview

In order to make available the attached files preview, run this command line :

/bin/sed -i -e 's/^\(.*mailbox.*show_preview.*=\).*;/\1 true;/' /var/www/horde-webmail/imp/config/conf.php

Enabling the cache

In order to make the messages display faster, you need to enable the use of cache in IMP. To do this, run the command line :

/bin/sed -i -e 's/^\(.*mboxcache.*use_mboxcache.*=\).*;/\1 true;/' /var/www/horde-webmail/imp/config/conf.php

And configure the cache :

/bin/sed -i -e "/^\(.*conf.*mboxcache.*use_mboxcache.*=\).*/i\
\$conf['mboxcache']['use_compress'] = false;\n\
\$conf['mboxcache']['preview_size'] = 1000;\n\
\$conf['mboxcache']['lifetime'] = 2592000;" /var/www/horde-webmail/imp/config/conf.php

This command lines will do the same for messages list :

/bin/sed -i -e 's/^\(.*mlistcache.*use_mlistcache.*=\).*;/\1 true;/' /var/www/horde-webmail/imp/config/conf.php
/bin/sed -i -e "/^\(.*conf.*mlistcache.*use_mlistcache.*=\).*/i\
\$conf['mlistcache']['lifetime'] = 604800;" /var/www/horde-webmail/imp/config/conf.php

Priority and attached files presence display in the messages list

In order to display mail priority and attached files presence in the messages list, use the following command line (the cache should be enabled) :

/bin/sed -i -e 's/^\(.*mailbox.*show_attachments.*=\).*;/\1 true;/' \
            -e 's/^\(.*mailbox.*show_xpriority.*=\).*;/\1 true;/' \
         /var/www/horde-webmail/imp/config/conf.php

CSS and Javascript Cache

In order to accelerate pages loading, it is possible to lighten Javascript and CSS files. This is the goal of this configuration :

• For Javascript caching :
  

  /bin/sed -i -e 's/^\(.*server.*cachejs.*=\).*;/\1 true;/' /var/www/horde-webmail/imp/config/conf.php
  /bin/sed -i -e "/^\(.*conf.*server.*cachejs.*=\).*/i\
  \$conf['server']['cachejsparams']['timeout'] = 86400;\n\
  \$conf['server']['cachejsparams']['mtime'] = false;" /var/www/horde-webmail/imp/config/conf.php
  

• For CSS caching :
  

  /bin/sed -i -e 's/^\(.*server.*cachecss.*=\).*;/\1 true;/' /var/www/horde-webmail/imp/config/conf.php
  /bin/sed -i -e "/^\(.*conf.*server.*cachecss.*=\).*/i\
  \$conf['server']['cachecssparams']['timeout'] = 86400;\n\
  \$conf['server']['cachecssparams']['mtime'] = false;" /var/www/horde-webmail/imp/config/conf.php

Note : If DIMP is present, you can activate the Javascript and CSS caching for this GUI :

• For Javascript caching :
  

  /bin/sed -i -e 's/^\(.*server.*cachejs.*=\).*;/\1 true;/' /var/www/horde-webmail/dimp/config/conf.php
  /bin/sed -i -e "/^\(.*conf.*server.*cachejs.*=\).*/i\
  \$conf['server']['cachejsparams']['timeout'] = 86400;\n\
  \$conf['server']['cachejsparams']['mtime'] = false;" /var/www/horde-webmail/dimp/config/conf.php
  

• For CSS caching :
  

  /bin/sed -i -e 's/^\(.*server.*cachecss.*=\).*;/\1 true;/' /var/www/horde-webmail/dimp/config/conf.php
  /bin/sed -i -e "/^\(.*conf.*server.*cachecss.*=\).*/i\
  \$conf['server']['cachecssparams']['timeout'] = 86400;\n\
  \$conf['server']['cachecssparams']['mtime'] = false;" /var/www/horde-webmail/dimp/config/conf.php

Enhancements

You will find in this section various little things that, without being mandatory, will enhance greatly your Horde installation.

Fortunes

In order to get a fun message each time you log in, install the needed software :

/usr/bin/apt-get install fortunes

And configure Horde to use it :

/bin/sed -i -e "/^\(.*conf.*portal.*fixed_blocks.*=\).*/a\
\$conf['fortune']['exec_path'] = '/usr/games/fortune';" /var/www/horde-webmail/config/conf.php

Spell checking

In order to check the spelling of the mails you write, install aSpell :

/usr/bin/apt-get install aspell-en aspell-fr

And configure IMP to use it :

/bin/sed -i \
  -e "s/^\(.*spell.*driver.*=\).*;/\1 'aspell';/" \
  -e "/^\(.*conf.*spell.*driver.*=\).*/i\
\$conf['spell']['path'] = '/usr/bin/aspell';" /var/www/horde-webmail/imp/config/conf.php

Encryption

Il you want to encrypt your mails using GnuPG, install GnuPG :

/usr/bin/apt-get install gnupg

And configure IMP to user it :

/bin/sed -i -e "/^\(.*conf.*utils.*gnupg_keyserver.*=\).*/i\
\$conf['utils']['gnupg'] = '/usr/bin/gpg';" /var/www/horde-webmail/imp/config/conf.php

We also configure Mnemo to use it :

/bin/sed -i -e "/^\(.*conf.*menu.*print.*=\).*/i\
\$conf['utils']['gnupg'] = '/usr/bin/gpg';" /var/www/horde-webmail/mnemo/config/conf.php

OpenSSL

I have not understand the goal of this, but if this is of use to you, here is how to enable it. Install OpenSSL :

/usr/bin/apt-get install openssl ca-certificates

And configure IMP to use it :

/bin/sed -i -e "/^\(.*conf.*utils.*gnupg_timeout.*=\).*/a\
\$conf['utils']['openssl_cafile'] = '/etc/ssl/certs';\n\
\$conf['utils']['openssl_binary'] = '/usr/bin/openssl';" /var/www/horde-webmail/imp/config/conf.php

More

Here is a list of things i don't talk about in this article, but that you can find in Horde configuration interface :

• Meteo from weather.com
• IP addresses geolocation
• Google Search API
• Google Maps API

I encourage you to explore Horde configuration if these tools are of use to you.

Setup with Cyrus Imap

If you have a Cyrus Imap server, you probably want Horde to configure your mails filters in Sieve. In order to do this, we need to install one more PEAR package :

/usr/bin/pear install Net_Sieve

Once this done, you need to edit the Sieve backend of Ingo :

/usr/bin/vim /var/www/horde-webmail/ingo/config/backends.php

You will find in this file a backend named 'sieve'. You need to change the values of 'preferred' and 'hostspec' to fit your needs. Then delete or comment the other backends to allow Ingo to use Sieve as filtering engine.

You also need to edit the 'hordeauth' value, it need to be changed from "true" to "'full'" :

 'hordeauth' => 'full',

Users black list

/bin/sed -i -e "s/^\(.*hooks.*preauthenticate.*=\).*;/\1 true;/" /var/www/horde-webmail/config/conf.php

/bin/sed -i -e "/^\(.*auth.*driver.*=\).*/a\
\$conf['auth']['blacklist'] = array( /* 'my_blacklisted_login', */ );" /var/www/horde-webmail/config/conf.php

Then, add your custom hook function to the hooks.php file :

echo "
// Here is an _horde_hook_preauthenticate that allow you to black list logins.
if (! function_exists('_horde_hook_preauthenticate')) {
    function _horde_hook_preauthenticate(\$userID, \$credential, \$realm)
    {
        return ! in_array(\$userID, \$GLOBALS['conf']['auth']['blacklist']);
    }
}" | /usr/bin/tee -a /var/www/horde-webmail/config/hooks.php

From now on, you can add a login to the black list with the following command lines. First, setup the login to blacklist :

LOGIN=blacklisted_user

And run this command line to add it to the black list configuration :

/bin/sed -i -e "s/^\(.*auth.*blacklist.*=.*\));.*/\1 '$LOGIN',);/" /var/www/horde-webmail/config/conf.php

Use behind a proxy serveur

If you want to use Apache 2 or Squid as a proxy before your Horde server, here are the change to make (for a proxy server using HTTPS and with Horde as /) :

• In the file /var/www/horde-webmail/config/conf.php :
  

  $conf['use_ssl'] = 1;
  $conf['server']['name'] = 'imp.votre-domaine.fr';
  $conf['server']['port'] = 443;
  ...
  $conf['cookie']['domain'] = $conf['server']['name'];
  $conf['cookie']['path'] = '/';

• In the file /var/www/horde-webmail/config/registry.php :
  

      'webroot' => '' /* _detect_webroot() */,

Security enhancement

Warning : run this step only when your Horde is perfectly configured, but before opening it to the Internet users.

In order to harden Horde, we change configuration files permissions :

/usr/bin/find /var/www/horde-webmail -type f -wholename "*config/*" | /usr/bin/xargs /bin/chown -R root:www-data
/usr/bin/find /var/www/horde-webmail -type f -wholename "*config/*" | /usr/bin/xargs /bin/chmod 0440

We disable the test.php files :

/usr/bin/find /var/www/horde-webmail -type f -name "test.php" | /usr/bin/xargs /bin/chmod a-rwx

We allow access to the configuration scripts to the root user only :

/usr/bin/find /var/www/horde-webmail -type d -name "scripts" | /usr/bin/xargs /bin/chown -R root:root
/usr/bin/find /var/www/horde-webmail -type d -name "scripts" | /usr/bin/xargs /bin/chmod -R go-rwx

And to harden even more our Horde install, we disable the write permission on all of Horde source :

/bin/chmod -R ugo-w /var/www/horde-webmail

We disable the display of PHP source code to users when errors occurs :

/bin/echo "# Secure PHP for horde
expose_php = Off
display_errors = Off
log_errors = On
register_globals = Off
" | tee /etc/php5/conf.d/horde.ini

And we restart Apache 2 to enable this configuration :

/etc/init.d/apache2 restart

I also encourage you to use Horde through a HTTPS connection in order to your emails account passwords no to be readable on the network.

Thanks

• Thanks to the Horde developers.
• Thanks to the writers of Installing Horde Groupware Webmail Edition.