A unikernel that can run as a QubesOS ProxyVM, replacing sys-firewall. It uses the mirage-qubes library to implement the Qubes protocols.

Note: This firewall ignores the rules set in the Qubes GUI. See rules.ml for the actual policy.

See A Unikernel Firewall for QubesOS for more details.

Pre-built binaries are available from the releases page.

Clone this Git repository and run the build-with-docker.sh script:

sudo ln -s /var/lib/docker /home/user/docker
sudo dnf install docker
sudo systemctl start docker
git clone https://github.com/talex5/qubes-mirage-firewall.git
cd qubes-mirage-firewall
sudo ./build-with-docker.sh

This took about 10 minutes on my laptop (it will be much quicker if you run it again). The symlink step at the start isn't needed if your build VM is standalone. It gives Docker more disk space and avoids losing the Docker image cache when you reboot the Qube.

Note: the object files are stored in the _build directory to speed up incremental builds. If you change the dependencies, you will need to delete this directory before rebuilding.

You can also build without Docker, as for any normal Mirage unikernel; see the Mirage installation instructions for details.

If you want to deploy manually, unpack mirage-firewall.tar.bz2 in dom0, inside /var/lib/qubes/vm-kernels/. e.g. (if dev is the AppVM where you built it):

[tal@dom0 ~]$ cd /var/lib/qubes/vm-kernels/
[tal@dom0 vm-kernels]$ qvm-run -p dev 'cat qubes-mirage-firewall/mirage-firewall.tar.bz2' | tar xjf -

The tarball contains vmlinuz, which is the unikernel itself, plus a couple of dummy files that Qubes requires.

To configure your new firewall using the Qubes 3 Manager GUI:

• Create a new ProxyVM named mirage-firewall to run the unikernel.
• You can use any template, and make it standalone or not. It doesn’t matter, since we don’t use the hard disk.
• Set the type to ProxyVM.
• Select sys-net for networking (not sys-firewall).
• Click OK to create the VM.
• Go to the VM settings, and look in the Advanced tab:
  • Set the kernel to mirage-firewall.
  • Turn off memory balancing and set the memory to 32 MB or so (you might have to fight a bit with the Qubes GUI to get it this low).
  • Set VCPUs (number of virtual CPUs) to 1.

Run this command in dom0 to create a mirage-firewall VM using the mirage-firewall kernel you added above:

qvm-create \
  --property kernel=mirage-firewall \
  --property kernelopts=None \
  --property memory=32 \
  --property maxmem=32 \
  --property netvm=sys-net \
  --property provides_network=True \
  --property vcpus=1 \
  --property virt_mode=pv \
  --label=green \
  --class StandaloneVM \
  mirage-firewall

You can run mirage-firewall alongside your existing sys-firewall and you can choose which AppVMs use which firewall using the GUI. To configure an AppVM to use it, go to the app VM's settings in the GUI and change its NetVM from default (sys-firewall) to mirage-firewall.

You can also configure it by running this command in dom0 (replace my-app-vm with the AppVM's name):

qvm-prefs --set my-app-vm netvm mirage-firewall

Alternatively, you can configure mirage-firewall to be your default firewall VM.

For development, use the test-mirage scripts to deploy the unikernel (qubes_firewall.xen) from your development AppVM. This takes a little more setting up the first time, but will be much quicker after that. e.g.

$ test-mirage qubes_firewall.xen mirage-firewall
Waiting for 'Ready'... OK
Uploading 'qubes_firewall.xen' (5901080 bytes) to "mirage-firewall"
Waiting for 'Booting'... OK
--> Loading the VM (type = ProxyVM)...
--> Starting Qubes DB...
--> Setting Qubes DB info for the VM...
--> Updating firewall rules...
--> Starting the VM...
--> Starting the qrexec daemon...
Waiting for VM's qrexec agent.connected
--> Starting Qubes GUId...
Connecting to VM's GUI agent: .connected
--> Sending monitor layout...
--> Waiting for qubes-session...
Connecting to mirage-firewall console...
MirageOS booting...
Initialising timer interface
Initialising console ... done.
gnttab_stubs.c: initialised mini-os gntmap
2017-03-18 11:32:37 -00:00: INF [qubes.rexec] waiting for client...
2017-03-18 11:32:37 -00:00: INF [qubes.gui] waiting for client...
2017-03-18 11:32:37 -00:00: INF [qubes.db] connecting to server...
2017-03-18 11:32:37 -00:00: INF [qubes.db] connected
2017-03-18 11:32:37 -00:00: INF [qubes.rexec] client connected, using protocol version 2
2017-03-18 11:32:37 -00:00: INF [qubes.db] got update: "/qubes-keyboard" = "xkb_keymap {\n\txkb_keycodes  { include \"evdev+aliases(qwerty)\"\t};\n\txkb_types     { include \"complete\"\t};\n\txkb_compat    { include \"complete\"\t};\n\txkb_symbols   { include \"pc+gb+inet(evdev)\"\t};\n\txkb_geometry  { include \"pc(pc105)\"\t};\n};"
2017-03-18 11:32:37 -00:00: INF [qubes.gui] client connected (screen size: 6720x2160)
2017-03-18 11:32:37 -00:00: INF [unikernel] Qubes agents connected in 0.095 s (CPU time used since boot: 0.008 s)
2017-03-18 11:32:37 -00:00: INF [net-xen:frontend] connect 0
2017-03-18 11:32:37 -00:00: INF [memory_pressure] Writing meminfo: free 6584 / 17504 kB (37.61 %)
Note: cannot write Xen 'control' directory
2017-03-18 11:32:37 -00:00: INF [net-xen:frontend] create: id=0 domid=1
2017-03-18 11:32:37 -00:00: INF [net-xen:frontend]  sg:true gso_tcpv4:true rx_copy:true rx_flip:false smart_poll:false
2017-03-18 11:32:37 -00:00: INF [net-xen:frontend] MAC: 00:16:3e:5e:6c:11
2017-03-18 11:32:37 -00:00: WRN [command] << Unknown command "QUBESRPC qubes.SetMonitorLayout dom0"
2017-03-18 11:32:38 -00:00: INF [ethif] Connected Ethernet interface 00:16:3e:5e:6c:11
2017-03-18 11:32:38 -00:00: INF [arpv4] Connected arpv4 device on 00:16:3e:5e:6c:11
2017-03-18 11:32:38 -00:00: INF [dao] Watching backend/vif
2017-03-18 11:32:38 -00:00: INF [qubes.db] got update: "/qubes-netvm-domid" = "1"

Copyright (c) 2018, Thomas Leonard All rights reserved.

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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. gg