qusal/salt/sys-syncthing

sys-syncthing

Syncthing through Qrexec in Qubes OS.

Table of Contents

• Description
• Installation
• Access Control
• Usage
• Debugging
• Uninstallation
• Credits

Description

Creates a Syncthing qube named "sys-syncthing", it will be attached to the "default_netvm". It makes no sense to run this with "sys-syncthing" attached to a VPN or Tor proxy.

This package opens up the qubes-firewall, so that the "sys-syncthing" qube is accessible externally.

Installation

• Top:

sudo qubesctl top.enable sys-syncthing browser
sudo qubesctl --targets=tpl-browser,sys-syncthing-browser,tpl-sys-syncthing,sys-syncthing state.apply
sudo qubesctl top.disable sys-syncthing browser
sudo qubesctl state.apply sys-syncthing.appmenus
qvm-port-forward -a add -q sys-syncthing -n tcp -p 22000
qvm-port-forward -a add -q sys-syncthing -n udp -p 22000

• State:

sudo qubesctl state.apply sys-syncthing.create
sudo qubesctl --skip-dom0 --targets=tpl-browser state.apply browser.install
sudo qubesctl --skip-dom0 --targets=tpl-sys-syncthing state.apply sys-syncthing.install
sudo qubesctl --skip-dom0 --targets=sys-syncthing state.apply sys-syncthing.configure
sudo qubesctl --skip-dom0 --targets=sys-syncthing-browser state.apply sys-syncthing.configure-browser
sudo qubesctl state.apply sys-syncthing.appmenus
qvm-port-forward -a add -q sys-syncthing -n tcp -p 22000
qvm-port-forward -a add -q sys-syncthing -n udp -p 22000

Install Syncthing on the client template:

sudo qubesctl --skip-dom0 --targets=TEMPLATE state.apply sys-syncthing.install-client

The client qube requires the split Syncthing service to be enabled:

qvm-features QUBE service.syncthing-setup 1

Access Control

A qusal.Syncthing service is created to allow use of Syncthing over Qrexec. The default policy asks if you want to sync with the sys-syncthing qube.

If you want to allow Syncthing between qubes, insert in you user policy file /etc/qubes/policy.d/30-user.policy to allow the service using the following format:

qusal.Syncthing  *  SOURCE  @default allow target=DESTINATION default_target=DEFAULT_DESTINATION

Usage

The Syncthing address is http://127.0.0.1:8384.

If you want to view statistics or manage the server through a GUI, open sys-syncthing or sys-syncthing-browser desktop file syncthing-browser.desktop from Dom0 or run syncthing -browser-only from sys-syncthing. Addresses starting with http or https will be redirected to sys-syncthing-browser.

The browser separation from the server is to avoid browsing malicious sites and exposing the browser to direct network on the same machine the server is running. The browser qube is offline and only has access to the admin interface. In other words, it has control over the server functions, if the browser is compromised, it can compromise the server.

To use the service, from the client, add a Remote Device, and copy the DeviceID from the server qube. On the Advanced tab, under Addresses, change dynamic to tcp://127.0.0.1:22001

If the sender qube has no netvm set, under Settings, disable Enable NAT traversal, Local Discovery, Global Discovery, and Enable Relaying

Debugging

If sys-net has more than one network card the first external interface will be used by default. If this is incorrect, you must change it manually. In Dom0 run:

qvm-port-forward -a del -q sys-syncthing -n udp -p 22000
qvm-port-forward -a del -q sys-syncthing -n tcp -p 22000
qvm-port-forward -a add -q sys-syncthing -n udp -p 22000
qvm-port-forward -a add -q sys-syncthing -n tcp -p 22000

This will let you choose the NIC.

Uninstallation

The sys-syncthing qube will not be removed, but the Syncthing service on that qube will be stopped. The firewall rules will be reverted so the qube will not be accessible externally. Note: If you have manually set rules you must manually revert them. The Qrexec policy will be reverted to stop Syncthing between qubes.

Uninstallation procedure:

qvm-port-forward -a del -q sys-syncthing -n tcp -p 22000
qvm-port-forward -a del -q sys-syncthing -n udp -p 22000
sudo qubesctl --skip-dom0 --targets=sys-syncthing state.apply sys-syncthing.cancel
sudo qubesctl state.apply sys-syncthing.clean

Credits

• Unman