OpenVPN
For more information, see http://www.openvpn.net/.
Setting up an OpenVPN server
yum install openvpn.$HOSTTYPE
- Copy
/usr/share/openvpn/easy-rsa/2.0
somewhere (like root's home directory withcp -ai /usr/share/openvpn/easy-rsa/2.0 ~/easy-rsa
). cd ~/easy-rsa
- Edit
vars
appropriately. . vars
./clean-all
- Before continuing, make sure the system time is correct. Preferably, set up NTP .
./build-ca
./build-inter $( hostname | cut -d. -f1 )
./build-dh
mkdir /etc/openvpn/keys
cp -ai keys/$( hostname | cut -d. -f1 ).{crt,key} keys/ca.crt keys/dh*.pem /etc/openvpn/keys/
cp -ai /usr/share/doc/openvpn-*/sample-config-files/roadwarrior-server.conf /etc/openvpn/server.conf
- Edit
/etc/openvpn/server.conf
appropriately to set your configuration and key paths, which are found in /etc/openvpn/keys/. - Fix selinux context of files:
- restorecon -Rv /etc/openvpn
- If you have feodra 14 or earlier:
chkconfig --level 2345 openvpn on
service openvpn start
- If you have fedora 15 or later (Note that 'server' corresponds with the configuration name in /etc/openvpn/ such as server.conf):
ln -s /lib/systemd/system/openvpn\@.service /etc/systemd/system/multi-user.target.wants/openvpn\@server.service
systemctl enable openvpn@server.service
systemctl start openvpn@server.service
- Verify that firewall rules allow traffic in from
tun+
, out from the LAN totun+
, and in from the outside on UDP port 1194.
The following should work (assuming an outside interface is eth1 and an inside interface is eth0):
iptables -A INPUT -i eth1 -p udp --dport 1194 -j ACCEPT iptables -A INPUT -i tun+ -j ACCEPT iptables -A FORWARD -i tun+ -j ACCEPT iptables -A FORWARD -i eth0 -o tun+ -j ACCEPT iptables -A FORWARD -i eth1 -o tun+ -m state --state ESTABLISHED,RELATED -j ACCEPT
Or for genfw (my firewall-generation script, not currently available in Fedora), this in /etc/sysconfig/genfw/rules
:
append INPUT -i eth1 -p udp --dport 1194 -j ACCEPT append INPUT -i tun+ -j ACCEPT append FORWARD -i tun+ -j ACCEPT append FORWARD -i eth0 -o tun+ -j ACCEPT append FORWARD -i eth1 -o tun+ -j established
Or for system-config-firewall, you can add these custom rules:
-A INPUT -i eth1 -p udp --dport 1194 -j ACCEPT -A INPUT -i tun+ -j ACCEPT -A FORWARD -i tun+ -j ACCEPT -A FORWARD -i eth0 -o tun+ -j ACCEPT -A FORWARD -i eth1 -o tun+ -m state --state ESTABLISHED,RELATED -j ACCEPT
Create a file iptables-rules in /etc/sysconfig and add the above contents, then in system-config-firewall, choose the "Custom Rules" choice, click "Add", choose IPV4 for the protocol type, and filter for the firewall table. Then select /etc/sysconfig/iptables-rules for the File: choice. Then Apply the changes.
Setting up a Linux OpenVPN client
You need to generate new keys (or use existing other client/username keys) for the new client/username
On the server:
cd easy-rsa
. vars
./build-key
username
On the client:
- Copy username.key, username.crt and ca.crt from server to
/etc/openvpn/keys/
. cp -ai /usr/share/doc/openvpn-*/sample-config-files/roadwarrior-client.conf /etc/openvpn/client.conf
- Edit
/etc/openvpn/client.conf
appropriately to set your configuration (just like server configuration, port, compression,..) and key paths. chkconfig --level 2345 openvpn on
service openvpn start
check /var/log/messages
if things didn't work as expected
Alternatively, on the client, after copying the keys onto the client machine, you can use NetworkManager to add a vpn connection. Make sure you have the NetworkManager-openvpn package installed. Then just add a new VPN connection.
Setting up a Windows OpenVPN client
On the server:
cd easy-rsa
. vars
./build-key
username
On the client:
- Install the OpenVPN GUI or the stand-alone OpenVPN client.
- Copy username.crt, username.key, and ca.crt to
C:\Program Files\OpenVPN\config\
on the client. - Drop roadwarrior-client.conf into
C:\Program Files\OpenVPN\config\
as whatever.ovpn and edit appropriately. - Either use the GUI to start the connection, start the OpenVPN service manually, or set the OpenVPN service to start automatically.
Ideally the client should do some verification on the server key with tls-remote
in the whatever.ovpn configuration file.