qubes-doc/configuration/vpn.md
2018-03-01 22:02:44 -06:00

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---
layout: doc
title: VPN
permalink: /doc/vpn/
redirect_from:
- /doc/privacy/vpn/
- /en/doc/vpn/
- /doc/VPN/
- /wiki/VPN/
---
How To make a VPN Gateway in Qubes
==================================
Although setting up a VPN connection is not by itself Qubes specific, Qubes includes a number of tools that can make the client-side setup of your VPN more versatile and secure. This document is a Qubes-specific outline for choosing the type of VM to use, and shows how to prepare a ProxyVM for either NetworkManager or a set of fail-safe VPN scripts.
Please refer to your guest OS and VPN service documentation when considering the specific steps and parameters for your connection(s); The relevant documentation for the Qubes default guest OS (Fedora) is [Establishing a VPN Connection.](https://docs.fedoraproject.org/en-US/Fedora/23/html/Networking_Guide/sec-Establishing_a_VPN_Connection.html)
### NetVM
The simplest case is to set up a VPN connection using the NetworkManager service inside your NetVM. Because the NetworkManager service is already started, you are ready to set up your VPN connection. However this has some disadvantages:
- You have to place (and probably save) your VPN credentials inside the NetVM, which is directly connected to the outside world
- All your AppVMs which are connected to the NetVM will be connected to the VPN (by default)
### AppVM
While the NetworkManager service is not started here (for a good reason), you can configure any kind of VPN client in your AppVM as well. However this is only suggested if your VPN client has special requirements.
### ProxyVM
One of the best unique features of Qubes OS is its special type of VM called a ProxyVM. The special thing is that your AppVMs see this as a NetVM (or uplink), and your NetVMs see it as a downstream AppVM. Because of this, you can place a ProxyVM between your AppVMs and your NetVM. This is how the default sys-firewall VM functions.
Using a ProxyVM to set up a VPN client gives you the ability to:
- Separate your VPN credentials from your NetVM.
- Separate your VPN credentials from your AppVM data.
- Easily control which of your AppVMs are connected to your VPN by simply setting it as a NetVM of the desired AppVM.
Set up a ProxyVM as a VPN gateway using NetworkManager
------------------------------------------------------
1. Create a new VM, name it, click the ProxyVM radio button, and choose a color and template.
![Create\_New\_VM.png](/attachment/wiki/VPN/Create_New_VM.png)
2. Add the `network-manager` service to this new VM.
![Settings-services.png](/attachment/wiki/VPN/Settings-services.png)
3. Set up your VPN as described in the NetworkManager documentation linked above.
4. Configure your AppVMs to use the new VM as a NetVM.
![Settings-NetVM.png](/attachment/wiki/VPN/Settings-NetVM.png)
5. Optionally, you can install some [custom icons](https://github.com/Zrubi/qubes-artwork-proxy-vpn) for your VPN
Set up a ProxyVM as a VPN gateway using iptables and CLI scripts
----------------------------------------------------------------
This method is more involved than the one above, but has anti-leak features that also make the connection _fail closed_ should it be interrupted.
It has been tested with Fedora 23 and Debian 8 templates.
1. Create a new VM, name it, click the ProxyVM radio button, and choose a color and template.
![Create\_New\_VM.png](/attachment/wiki/VPN/Create_New_VM.png)
Note: Do not enable NetworkManager in the ProxyVM, as it can interfere with the scripts' DNS features.
If you enabled NetworkManager or used other methods in a previous attempt, do not re-use the old ProxyVM...
Create a new one according to this step.
If your choice of TemplateVM doesn't already have the VPN client software, you'll need to install the software in the template before proceeding.
Disable any auto-starting service that comes with the software package.
For example for OpenVPN.
sudo systemctl disable openvpn.service
You may also wish to install `nano` or another simple text editor for entering the scripts below.
2. Set up and test the VPN client.
Make sure the VPN VM and its TemplateVM is not running.
Run a terminal (CLI) in the VPN VM -- this will start the VM.
Then create a new `/rw/config/vpn` folder with.
sudo mkdir /rw/config/vpn
Copy your VPN config files to `/rw/config/vpn`.
Your VPN config file should be named `openvpn-client.ovpn`) so you can use the scripts below as is without modification.
Otherwise you would have to replace the file name.
`openvpn-client.ovpn` contents:
* Files accompanying the main config such as `*.crt` and `*.pem` should also go to `/rw/config/vpn` folder.
* Files referenced in `openvpn-client.ovpn` should not use absolute paths such as `/etc/...`.
The VPN scripts here are intended to work with commonly used `tun` interfaces, whereas `tap` mode is untested.
Also, the config should route all traffic through your VPN's interface after a connection is created; For OpenVPN the directive for this is `redirect-gateway def1`.
sudo nano /rw/config/vpn/openvpn-client.ovpn
Make sure it already includes or add:
redirect-gateway def1
The VPN client may not be able to prompt you for credentials when connecting to the server.
Create a file in the `/rw/config/vpn` folder with your credentials and using a directive.
For example for OpenVPN, add:
auth-user-pass pass.txt
Save file `/rw/config/vpn/openvpn-client.ovpn`.
Make sure a `/rw/config/vpn/pass.txt` file actually exists.
sudo nano /rw/config/vpn/pass.txt
Add:
username
password
Replace `username` and `password` with your actual username and password.
**Test your client configuration:**
Run the client from a CLI prompt in the 'vpn' folder, preferably as root.
For example:
sudo openvpn --cd /rw/config/vpn --config openvpn-client.ovpn
Watch for status messages that indicate whether the connection is successful and test from another VPN VM terminal window with `ping`.
ping 8.8.8.8
`ping` can be aborted by pressing the two keys `ctrl` + `c` at the same time.
DNS may be tested at this point by replacing addresses in `/etc/resolv.conf` with ones appropriate for your VPN (although this file will not be used when setup is complete).
Diagnose any connection problems using resources such as client documentation and help from your VPN service provider.
Proceed to the next step when you're sure the basic VPN connection is working.
3. Create the DNS-handling script.
sudo nano /rw/config/vpn/qubes-vpn-handler.sh
Edit and add:
~~~
#!/bin/bash
set -e
export PATH="$PATH:/usr/sbin:/sbin"
case "$1" in
up)
# To override DHCP DNS, assign DNS addresses to 'vpn_dns' env variable before calling this script;
# Format is 'X.X.X.X Y.Y.Y.Y [...]'
if [[ -z "$vpn_dns" ]] ; then
# Parses DHCP foreign_option_* vars to automatically set DNS address translation:
for optionname in ${!foreign_option_*} ; do
option="${!optionname}"
unset fops; fops=($option)
if [ ${fops[1]} == "DNS" ] ; then vpn_dns="$vpn_dns ${fops[2]}" ; fi
done
fi
iptables -t nat -F PR-QBS
if [[ -n "$vpn_dns" ]] ; then
# Set DNS address translation in firewall:
for addr in $vpn_dns; do
iptables -t nat -A PR-QBS -i vif+ -p udp --dport 53 -j DNAT --to $addr
iptables -t nat -A PR-QBS -i vif+ -p tcp --dport 53 -j DNAT --to $addr
done
su - -c 'notify-send "$(hostname): LINK IS UP." --icon=network-idle' user
else
su - -c 'notify-send "$(hostname): LINK UP, NO DNS!" --icon=dialog-error' user
fi
;;
down)
su - -c 'notify-send "$(hostname): LINK IS DOWN !" --icon=dialog-error' user
;;
esac
~~~
Save the script.
Make it executable.
sudo chmod +x /rw/config/vpn/qubes-vpn-handler.sh
4. Configure client to use the DNS handling script. Using openvpn as an example, edit the config.
sudo nano /rw/config/vpn/openvpn-client.ovpn
Add the following.
script-security 2
up 'qubes-vpn-handler.sh up'
down 'qubes-vpn-handler.sh down'
Remove other instances of lines starting with `script-security`, `up` or `down` should there be any others.
Save the script.
**Restart the client and test the connection again** ...this time from an AppVM!
5. Set up iptables anti-leak rules.
Edit the firewall script.
sudo nano /rw/config/qubes-firewall-user-script
Clear out the existing lines and add:
~~~
#!/bin/bash
# Block forwarding of connections through upstream network device
# (in case the vpn tunnel breaks):
iptables -I FORWARD -o eth0 -j DROP
iptables -I FORWARD -i eth0 -j DROP
# Block all outgoing traffic
iptables -P OUTPUT DROP
iptables -F OUTPUT
iptables -I OUTPUT -o lo -j ACCEPT
# Add the `qvpn` group to system, if it doesn't already exist
if ! grep -q "^qvpn:" /etc/group ; then
groupadd -rf qvpn
sync
fi
sleep 2s
# Allow traffic from the `qvpn` group to the uplink interface (eth0);
# Our VPN client will run with group `qvpn`.
iptables -I OUTPUT -p all -o eth0 -m owner --gid-owner qvpn -j ACCEPT
~~~
Save the script.
Make it executable.
sudo chmod +x /rw/config/qubes-firewall-user-script
5. Set up the VPN's autostart.
sudo nano /rw/config/rc.local
Clear out the existing lines and add:
~~~
#!/bin/bash
VPN_CLIENT='openvpn'
VPN_OPTIONS='--cd /rw/config/vpn/ --config openvpn-client.ovpn --daemon'
su - -c 'notify-send "$(hostname): Starting $VPN_CLIENT..." --icon=network-idle' user
groupadd -rf qvpn ; sleep 2s
sg qvpn -c "$VPN_CLIENT $VPN_OPTIONS"
~~~
If you are using anything other than OpenVPN, change the `VPN_CLIENT` and `VPN_OPTIONS` variables to match your VPN software.
Save the script.
Make it executable.
sudo chmod +x /rw/config/rc.local
6. Restart the new VM!
The link should then be established automatically with a popup notification to that effect.
Usage
-----
Configure your AppVMs to use the VPN VM as a NetVM...
![Settings-NetVM.png](/attachment/wiki/VPN/Settings-NetVM.png)
If you want to be able to use the [Qubes firewall](/doc/firewall), create a new FirewallVM (as a ProxyVM) and set it to use the VPN VM as its NetVM.
Then, configure AppVMs to use your new FirewallVM as their NetVM.
If you want to update your TemplateVMs through the VPN, enable the `qubes-updates-proxy` service in your new FirewallVM.
You can do this in the Services tab in Qubes VM Manager or on the command-line:
qvm-service -e <name> qubes-updates-proxy
Then, configure your templates to use your new FirewallVM as their NetVM.
Troubleshooting
---------------
* Always test your basic VPN connection before adding scripts.
* Test DNS: Ping a familiar domain name from an appVM. It should print the IP address for the domain.
* For scripting: Ping external IP addresses from inside the VPN VM using `sudo sg qvpn -c 'ping ...'`, then from an appVM using just `ping ...`. Once the firewall rules are in place, you will have to use `sudo sg` to run any IP network commands in the VPN VM.
* Use `iptables -L -v` and `iptables -L -v -t nat` to check firewall rules. The latter shows the critical PR-QBS chain that enables DNS forwarding.