# sys-usb

PCI handler of USB devices in Qubes OS.

## Table of Contents

* [Description](#description)
* [Installation](#installation)
  * [Keyboard installation](#keyboard-installation)
  * [AudioVM installation](#audiovm-installation)
  * [Client installation](#client-installation)
    * [Client USB proxy installation](#client-usb-proxy-installation)
    * [Client cryptsetup installation](#client-cryptsetup-installation)
    * [Client CTAP installation](#client-ctap-installation)
* [Access control](#access-control)
* [Usage](#usage)
  * [How to use audio devices](#how-to-use-audio-devices)
* [Credits](#credits)

## Description

Setup named disposables for USB qubes. During creation, it tries to separate
the USB controllers to different qubes is possible.

## Installation

- Top:
```sh
sudo qubesctl top.enable sys-usb
sudo qubesctl --targets=tpl-sys-usb state.apply
sudo qubesctl top.disable sys-usb
```

- State:
<!-- pkg:begin:post-install -->
```sh
sudo qubesctl state.apply sys-usb.create
sudo qubesctl --skip-dom0 --targets=tpl-sys-usb state.apply sys-usb.install
```
<!-- pkg:end:post-install -->

### Keyboard installation

If you use an USB keyboard, also run:
```sh
sudo qubesctl state.apply sys-usb.keyboard
```

### AudioVM installation

If you plan to use `disp-sys-usb` as an AudioVM:
```sh
sudo qubesctl --skip-dom0 --targets=tpl-sys-usb state.apply sys-audio.install
sudo qubesctl --skip-dom0 --targets=dvm-sys-usb state.apply sys-audio.configure-dvm
qvm-tags disp-sys-usb add audiovm
qvm-features disp-sys-usb service.audiovm 1
```
And set the qube preference `audiovm` to `disp-sys-usb`:
```sh
qvm-prefs QUBE audiovm disp-sys-usb
```

### Client installation

#### Client USB proxy installation

Install the proxy on the client template:
```sh
sudo qubesctl --skip-dom0 --targets=tpl-QUBE state.apply sys-usb.install-client-proxy
```

#### Client cryptsetup installation

If the client requires decrypting a device, install on the client template:
```sh
sudo qubesctl --skip-dom0 --targets=tpl-QUBE state.apply sys-usb.install-client-cryptsetup
```

#### Client CTAP installation

If the client requires a CTAP device, install on the client template:
```sh
sudo qubesctl --skip-dom0 --targets=tpl-QUBE state.apply sys-usb.install-client-fido
```
And enable the CTAP Proxy service for the client qubes:
```sh
qvm-features QUBE service.qubes-ctap-proxy 1
```

## Access control

No extra services are implemented, consult upstream to learn how to use the
following services:
- `qubes.InputMouse`, `qubes.InputKeyboard`, `qubes.InputTablet`;
- `ctap.GetInfo`, `ctap.ClientPin`, `u2f.Register`, `u2f.Authenticate`,
  `policy.RegisterArgument`.

## Usage

Depending on you system, one or more USB qubes will be created to hold the
different controllers. The qube names are `disp-sys-usb`, `disp-sys-usb-left`,
`disp-sys-usb-dock`.

Start a USB qube an connect a device to it. USB PCI devices will appear on the
system tray icon `qui-devices`. From there, assign it to the intended qube.

### How to use audio devices

Bluetooth and Camera are normally integrated in laptops, but they still are
USB devices internally. They will be held by `(disp-)sys-usb` or
`(disp-)sys-net`, else `dom0`.

Built-in microphones on the other hand, are directly attached to `dom0`.

To use these devices, there are two options:

1. Attaching the device (USB passthrough) to the audio client:
    - Advantages:
        - Easier setup as it doesn't require an AudioVM.
    - Disadvantages:
        - Increased latency;
        - Only one qube can use the device; and
        - Less secure as it exposes the Audio stack to the client.

2. Leaving devices to the AudioVM (`(disp-)sys-usb` as AudioVM):
    - Advantages:
        - More secure as the devices are not on the client;
        - Less latency; and
        - All audio clients will have the same audio capabilities.
    - Disadvantages:
        - Some applications might not work due to not finding the device.

3. Using [video-companion](../video-companion/README.md) to access webcam:
    - Advantages:
        - The most secure for client and server as the physical devices are
          unmanaged;
        - Least latency.
    - Disadvantages:
        - Can't use video-companion to screen share and share webcam at the
          same time; and
        - Does not cover audio.

## Credits

- [Unman](https://github.com/unman/shaker/blob/main/sys-usb)