Introduction
In case your workplace uses Microsoft Exchange for E-mail, and you want to Exchange E-mail account from those E-mail clients who do not provide support to Exchange protocol.
DavMail offers a solution by converting Microsoft Exchange to open protocols like IMAP,POP, SMTP, Carddav, LDAP and Caldav.
Installation
requires dependencies by Davmail for proper working. These can be installed with apt:
sudo apt-get install default-jre libswt-gtk-3-java libswt-cairo-gtk-3-jniA Debian package has been made available by theDavMail project on their website through [SourceForge (http://sourceforge.net/projects/davmail/files/davmail/).
To download the latest packages:
wget http://sourceforge.net/projects/davmail/files/davmail/4.4.1/davmail_4.4.1-2225-1_all.debNow DavMail can be installed with dpkg:
sudo dpkg -i davmail_4.4.1-2225-1_all.debBasic Configuration
By default, the configuration file of DavMail does not exist. You can use any text editor of yours for creating one:
sudo vi /etc/davmail.propertiesDavMail should be set to server mode so that X11 is not required by it:
davmail.server=trueNow remote mode needs to be enabled and bind address needs to be set to the IP address of your server or it can be set blank:
davmail.allowRemote=true
davmail.bindAddress=Set davmail.url to your Outlook Web Access/ Outlook Web App URL, that generally ends in/owa:
davmail.url=https://yourcompany.com/owaYour connection mode should be set to:
davmail.enableEws=autoThese are the ports options:
davmail.imapPort=993
davmail.smtpPort=465
davmail.ldapPort=636
davmail.popPort=995
davmail.caldavPort=8443Now save and close the configuration file.
Create A SSL Certificate
you need SSL private key to enable the SSL encryption, a SSL certificate in PEM format. In case the certificate has been bought from a Certificate Authority, then you should already possess your key and certificate. If this is the case, then continue to the section of Configuring SSL below. Alternatively, a self-signed certificate can be generated by following the steps given.
Use OpenSSL for generating a RSA key:
sudo openssl genrsa -out /usr/lib/ssl/private/davmail.key 2048Ensure that root owns the key and all the permissions are properly set:
sudo chown root:root /usr/lib/ssl/private/davmail.key
sudo chmod 600 /usr/lib/ssl/private/davmail.keyNow, a certificate signing request is to be created:
sudo openssl req -new -key /usr/lib/ssl/private/davmail.key -out /usr/lib/ssl/certs/davmail.csrMultiple questions will now be asked by OpenSSL.
Jstt follow the steps below:
Common Nameis the only important field that needs to be set to your server’s IP address or its domain name which email clients (like davmail.mydomain.com or 123.123.123.123) can then access.You can leave all the other fields with anything or can set them to their defaults just by just pressing enter:
You are about to be asked to enter information that will be incorporated into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [XX]:US
State or Province Name (full name) []:Pokhara
Locality Name (eg, city) [Default City]:Kathmandu
Organization Name (eg, company) [Default Company Ltd]:Tech-firm
Organizational Unit Name (eg, section) []:Keyboard Cat Department
Common Name (eg, your name or your server's hostname) []:mydomain.com
Email Address []:[email protected]
Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:Use your private key for signing the certificate and the expiration date can be set using the -days argument:
sudo openssl x509 -req -signkey /usr/lib/ssl/private/davmail.key -in /usr/lib/ssl/certs/davmail.csr -out /usr/lib/ssl/certs/davmail.crt -days 365The certificate will expire in a year (365 days) with these settings.
Now you possess an SSL certificate of your own!
Configuring SSL
Since you now possess your own SSL certificate, convert it to a format that can be understood by DavMail. The examples that follow will utilize the certificate and key that were generated above. In case a certificate is purchased from a Certificate Authority, then those files should be utilized instead of davmail.key and davmail.crt.
You need to begin by joining cat with yourkey and certificate file:
sudo -s cat /usr/lib/ssl/private/davmail.key /usr/lib/ssl/certs/davmail.crt > /usr/lib/ssl/certs/davmail.pem
exitAgain, permissions need to be set so that key file can only be accessed by the root:
sudo chown root:root /usr/lib/ssl/certs/davmail.pem
sudo chmod 600 /usr/lib/ssl/certs/davmail.pemNow your combined certificate and key needs to be converted to a pkcs12 file:
sudo openssl pkcs12 -export -in /usr/lib/ssl/certs/davmail.pem -out /usr/lib/ssl/certs/davmail.p12 -name “davmail”Prompt will be given for entering an export password and this field can not be left blank!
A password must be set for DavMail to work properly.
Permissions can be set by:
sudo chown root:root /usr/lib/ssl/certs/davmail.pem
sudo chmod 600 /usr/lib/ssl/certs/davmail.pemNow to open config file:
sudo vi /etc/davmail.propertiesThe configuration options provided below inform DavMail of the pkcs12 file’s location that was just generated and the set passphrase:
davmail.ssl.keystoreType=PKCS12
davmail.ssl.keystoreFile=/usr/lib/ssl/certs/davmail.p12
davmail.ssl.keyPass=password
davmail.ssl.keystorePass=passwordBoth davmail.ssl.keyPass and davmail.ssl.keystorePass should possess the exact value. The configuration file needs to be saved.
You can now utilize your SSL certificate as DavMail stands configured.
Start DavMail
As the Debian package that was earlier downloaded does not include an init script, therefore we need to create our own.
A new file can be created using your favored text editor:
sudo vi /etc/init.d/davmailThe following should be copied and pasted into the file:
#! /bin/sh
### BEGIN INIT INFO
# Provides: davmail
# Required-Start: $remote_fs $syslog
# Required-Stop: $remote_fs $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: DavMail Exchange gatway
# Description: A gateway between Microsoft Exchange and open protocols.
### END INIT INFO
PATH=/sbin:/usr/sbin:/bin:/usr/bin
DESC="Davmail Exchange gateway"
NAME=davmail
CONFIG=/etc/davmail.properties
DAEMON=/usr/bin/$NAME
DAEMON_ARGS="$CONFIG"
PIDFILE=/var/run/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME
LOGFILE=/var/log/davmail.log
# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0
# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] && . /etc/default/$NAME
# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh
# Define LSB log_* functions
. /lib/lsb/init-functions
#
# Function that starts the daemon/service
#
do_start()
{
start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
|| return 1
start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -- \
$DAEMON_ARGS >> $LOGFILE 2>&1 &
[ $? != 0 ] && return 2
echo $! > $PIDFILE
exit 0
}
#
# Function that stops the daemon/service
#
do_stop()
{
start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE
RETVAL="$?"
[ "$RETVAL" = 2 ] && return 2.
start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON
[ "$?" = 2 ] && return 2
rm -f $PIDFILE
return "$RETVAL"
}
case "$1" in
start)
[ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
do_start
case "$?" in
0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
esac
;;
stop)
[ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
do_stop
case "$?" in
0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
esac
;;
status)
status_of_proc "$DAEMON" "$NAME" && exit 0 || exit $?
;;
restart|force-reload)
log_daemon_msg "Restarting $DESC" "$NAME"
do_stop
case "$?" in
0|1)
do_start
case "$?" in
0) log_end_msg 0 ;;
1) log_end_msg 1 ;; # Old process is still running
*) log_end_msg 1 ;; # Failed to start
esac
;;
*)
# Failed to stop
log_end_msg 1
;;
esac
;;
*)
echo "Usage: $SCRIPTNAME {start|stop|status|restart| force-reload}" >&2
exit 3
;;
esacNow save and close the file.
The script can be marked as executable, the service can be started, and it can be enabled at boot:
sudo chmod +x /etc/init.d/davmail
sudo service davmail start
sudo update-rc.d davmail defaultsClient Configuration
Now server is up and running you can begin configuring your E-mail clients. You can utilize the “manual” options of your E-mail client for creating a new account.
Both the SMTP and IMAP server will be your server’s IP address or domain name, according to the Common Name that you have used on your SSL certificate. Your email address without domain name will be the username for both SMTP and IMAP. For instance: [email protected] is your email ID, so tom is your username. Ensure that both SMTP and IMAP have been set for utilizing SSL/TLS and not STARTTLS.
Some email clients of yours will generate warnings as a self-signed certificate is being used by you. However, since you created it yourself, accepting it is safe in this case.
You can now utilize your Microsoft Exchange E-mail account with open technologies for sending or receiving your E-mail!
