mirror of
https://github.com/Qubes-Community/Contents.git
synced 2024-12-24 06:39:25 -05:00
325 lines
13 KiB
Markdown
325 lines
13 KiB
Markdown
---
|
|
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.
|
|
|
|
|
|
|
|
2. Add the `network-manager` service to this new VM.
|
|
|
|
|
|
|
|
3. Set up your VPN as described in the NetworkManager documentation linked above.
|
|
|
|
4. (Optional) Make your VPN start automatically.
|
|
|
|
Edit `/rw/config/rc.local` and add these lines:
|
|
|
|
```bash
|
|
# Automatically connect to the VPN once Internet is up
|
|
while ! ping -c 1 -W 1 1.1.1.1; do
|
|
sleep 1
|
|
done
|
|
PWDFILE="/rw/config/NM-system-connections/secrets/passwd-file.txt"
|
|
nmcli connection up file-vpn-conn passwd-file $PWDFILE
|
|
```
|
|
You can find the actual "file-vpn-conn" in `/rw/config/NM-system-connections/`.
|
|
|
|
Create directory `/rw/config/NM-system-connections/secrets/` (You can put your `*.crt` and `*.pem` files here too).
|
|
Create a new file `/rw/config/NM-system-connections/secrets/passwd-file.txt`:
|
|
```
|
|
vpn.secrets.password:XXXXXXXXXXXXXX
|
|
```
|
|
And substitute "XXXXXXXXXXXXXX" for the actual password.
|
|
The contents of `passwd-file.txt` may differ depending on your VPN settings. See the [documentation for `nmcli up`](https://www.mankier.com/1/nmcli#up).
|
|
|
|
5. (Optional) Make the network fail-close for the AppVMs if the connection to the VPN breaks.
|
|
|
|
Edit `/rw/config/qubes-firewall-user-script` and add these lines:
|
|
```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
|
|
ip6tables -I FORWARD -o eth0 -j DROP
|
|
ip6tables -I FORWARD -i eth0 -j DROP
|
|
```
|
|
|
|
6. Configure your AppVMs to use the new VM as a NetVM.
|
|
|
|
|
|
|
|
7. 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.
|
|
|
|
|
|
|
|
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
|
|
ip6tables -I FORWARD -o eth0 -j DROP
|
|
ip6tables -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...
|
|
|
|
|
|
|
|
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.
|