diff options
Diffstat (limited to 'pairing.py')
| -rwxr-xr-x | pairing.py | 80 |
1 files changed, 68 insertions, 12 deletions
@@ -1,6 +1,8 @@ #!/usr/bin/env python3 import threading +import binascii import re +import os import serial import gi @@ -14,6 +16,7 @@ class PairingWindow(Gtk.Window): Gtk.Window.__init__(self, title='SecureHID pairing') self.noise = noise self.debug = debug + self.trusted = False self.set_border_width(10) self.set_default_size(600, 200) @@ -30,6 +33,16 @@ class PairingWindow(Gtk.Window): self.entry.set_editable(False) self.vbox.pack_start(self.entry, True, True, 0) + self.confirm_button = Gtk.Button(label='Trust this device') + self.confirm_button.connect('clicked', self.confirm_trust) + self.confirm_button.set_sensitive(False) + self.abort_button = Gtk.Button(label='Abort') + self.abort_button.connect('clicked', lambda _foo: self.destroy()) + self.bbox = Gtk.Box(orientation=Gtk.Orientation.HORIZONTAL, spacing=10) + self.bbox.pack_start(self.confirm_button, True, True, 0) + self.bbox.pack_start(self.abort_button, True, True, 0) + self.vbox.pack_start(self.bbox, True, True, 0) + self.add(self.vbox) self.handshaker = threading.Thread(target=self.pair, daemon=True) @@ -64,9 +77,19 @@ class PairingWindow(Gtk.Window): try: for user_input in self.noise.pairing_messages(): GLib.idle_add(update_text, user_input) - self.destroy() - except noise.ProtocolError as e: - GLib.idle_add(self.label.set_markup, f'<b>Error: {e}!</b>') + + GLib.idle_add(self.finish_pairing) + except hexnoise.ProtocolError as e: + GLib.idle_add(self.label.set_markup, f'<b>Error: {e}</b>') + + def finish_pairing(self): + self.label.set_markup(f'<b>Step 3</b>\n\nConfirm pairing.\n' + f'In case the device did not sound an alarm just now, confirm pairing now using the button below.') + self.confirm_button.set_sensitive(True) + + def confirm_trust(self, _foo): + self.trusted = True + self.destroy() class StatusIcon(Gtk.StatusIcon): @@ -75,12 +98,30 @@ class StatusIcon(Gtk.StatusIcon): self.set_tooltip_text('SecureHID connected') self.set_from_file('secureusb_icon.png') +def run_pairing_gui(port, baudrate, debug=False): + XDG_CONFIG_HOME = os.environ.get('XDG_CONFIG_HOME') or os.path.join(os.path.expandvars('$HOME'), '.config', 'secure_hid') + if not os.path.isdir(XDG_CONFIG_HOME): + os.mkdir(XDG_CONFIG_HOME) + + private_key_file = os.path.join(XDG_CONFIG_HOME, 'host_key.pem') + if not os.path.isfile(private_key_file): + with open(private_key_file, 'w') as f: + f.write(binascii.hexlify(hexnoise.NoiseEngine.generate_private_key_x25519()).decode()) + + known_devices_file = os.path.join(XDG_CONFIG_HOME, 'known_devices') + if not os.path.isfile(known_devices_file): + with open(known_devices_file, 'w') as f: + f.write('# This file contains the hex-encoded SHA-256 fingerprints of the X25519 keys of all trusted SecureHID devices\n') + + with open(private_key_file) as f: + host_key_private = binascii.unhexlify(f.read()) -def run_pairing_gui(serial, baudrate, debug=False): - ser = serial.Serial(serial, baudrate) - packetizer = hexnoise.Packetizer(serial, debug=debug) - noise = hexnoise.NoiseEngine(packetizer, debug=debug) + ser = serial.Serial(port, baudrate) + packetizer = hexnoise.Packetizer(ser, debug=debug) + noise = hexnoise.NoiseEngine(host_key_private, packetizer, debug=debug) noise.perform_handshake() + print('Connected.') + print('Device fingerprint:', noise.remote_fingerprint) if not noise.paired: window = PairingWindow(noise, debug=debug) @@ -88,12 +129,27 @@ def run_pairing_gui(serial, baudrate, debug=False): window.show_all() Gtk.main() - if self.noise.paired: - input_runner = threading.Thread(target=noise.uinput_passthrough, daemon=True) - input_runner.start() + if not window.trusted: + raise SystemError('User abort') - status_icon = StatusIcon() - Gtk.main() + if not noise.paired: + raise SystemError('Unknown noise error') + + with open(known_devices_file, 'a') as f: + f.write(noise.remote_fingerprint) + + else: + with open(known_devices_file) as f: + known_devices = [ l.strip() for l in f.readlines() if not l[0] == '#' ] + + if noise.remote_fingerprint not in known_devices: + raise ValueError('Remote host is untrusted but seems to trust us.') + + input_runner = threading.Thread(target=noise.uinput_passthrough, daemon=True) + input_runner.start() + + status_icon = StatusIcon() + Gtk.main() if __name__ == '__main__': import argparse |