Kiosk interface

The kiosk shows what it does on its touch screen: waiting for a key, scan progress, the dangerous files found, then the result. There are no buttons: the only action of the user is a touch anywhere on the screen to start the cleaning, once the files to remove are listed.

Waiting for a key	Scan in progress
Threats found: touch to clean	Key cleaned

Screens

Screen	When
ready	Waiting for a key (animation of a key inserted), with the versions of the kiosk and of its signatures
unavailable	No valid signatures: the kiosk only accepts a signature update device
scanning	Device, progress bar, files scanned out of the total, threats found so far, the latest files scanned and their verdict
threats	The files that will be removed, with their detection; a touch on the screen cleans the key
cleaning	The files being removed
clean	No threat found: the key can be used
warning	Suspicious or not fully scanned files are kept (scan.suspicious or scan.on_error set to warn)
cleaned	The removed files
not_cleaned	The files that could not be removed, or the key was removed before the cleaning
not_verified	Files that could not be scanned (scan.on_error = "block"): the key must not be used
error	The key could not be mounted or read
service	Maintenance, signature or image update device: the messages of the kiosk

A result (scan, maintenance or update device) stays on the screen until the key is removed, then display.return_seconds more (5 seconds by default) before the waiting screen. Inserting another key shows its scan at once.

How it is drawn

The screens are drawn with Pillow and copied into the Linux framebuffer (display.framebuffer, /dev/fb0): no display server, no browser, nothing that listens on a socket. The kiosk puts its console (tty1) in graphics mode, so that the kernel does not draw text over the screens. Touches are read from /dev/input/mice (the touch screen is seen as a mouse), only while the kiosk waits for the cleaning to be confirmed. File names and device labels come from the key: they are made printable (control and invisible formatting characters replaced) and cut to their place, never interpreted. The graphical interface needs a 24 or 32 bits per pixel framebuffer (Intel, efifb, QEMU).

The configuration selects it with kiosk.interface = "framebuffer" (the default); curses is the text interface (administrator mode), console prints plain text (development).

Customization

An administrator adapts the interface to the organization: logo, colors, texts of every screen and their language, images. The image is read-only (dm-verity): the theme is part of it, and a change needs a new image (or an image update).

Configuration

In packaging/pandora-box.toml, section [display]:

[display]
# Theme folder, installed in the image from image/theme/
theme = "/usr/share/pandora-box/theme"
# Language of the texts: "en", "fr", or a language the theme adds
language = "fr"
# Seconds before the waiting screen, once the key is removed
return_seconds = 5.0

Theme folder

Create image/theme/ in the repository: the image build copies it to /usr/share/pandora-box/theme and checks it (the build fails on an invalid theme). The folder holds a theme.toml and the files it names. Every key is optional: a key of the theme replaces the one of the built-in theme (src/pandora_box/ui/theme/theme.toml, which lists them all), the others are kept.

image/theme/
├── theme.toml
└── logo.png

# Logo of the organization, on the left of the header (PNG or JPEG)
logo = "logo.png"
# TrueType fonts, files of the folder (default: DejaVu Sans)
# font = "OpenSans-Regular.ttf"
# font_bold = "OpenSans-Bold.ttf"

[colors]
header = "#003366"
progress = "#003366"

[texts.fr]
title = "Hôpital de Mons - Borne antivirus"
footer = "Service informatique - poste 1234"
insert_help = "Analysez toute clé USB avant de l'utiliser sur un poste de l'hôpital."
clean_help = "Cette clé peut être utilisée. N'oubliez pas de la retirer."

Texts

Every text shown on the screen is a key of [texts.<language>]: the title of the header, the footer, the title and the help of each screen, the verdicts of the files. Some texts have placeholders, replaced by the kiosk:

Text	Placeholders
scan_progress	{done}, {total}
scan_threats, cleaned_help, more_files	{count}
device_usage	{size}, {used}

A text with an unknown placeholder or an unknown key is refused. A theme may add a language: [texts.de] with the texts it translates, the others are in English; then set display.language = "de".

The messages of the service, error, unavailable and cleaning screens are those of the kiosk logs (in English): they are meant for the administrator, and are not part of the theme.

Colors

header, header_text, background, text, muted (help, details), clean, threat, warning, progress, progress_background: "#rrggbb".

Images

[images]: insert (animation of the waiting screen, one image per second), busy (animation while the kiosk works), clean, threat, error (icons of the results). PNG (with transparency) or JPEG, at most 4096 pixels. The built-in images come from the first version of PandoraBox.

Check and preview a theme

Without a kiosk, on the development computer:

pandora-box-theme check image/theme
pandora-box-theme preview image/theme /tmp/preview            # every language
pandora-box-theme preview image/theme /tmp/preview --language fr --size 800x480

preview draws every screen, with made-up files, into PNG files. pandora-box --check-config also checks the theme of the configuration.