Trayicon plugin crashes EpixNet at startup with `--tor always` (Xlib X11 connection routed through PySocks)

[parkour86]

Step 1: Please describe your environment

• EpixNet version: 0.2.7 (source from main-fc3486d8f9e5196870aa451531cf4712a213ed02)
• Operating system: Ubuntu 24.04 (Python 3.12.3, Gevent 26.4.0)
• Web browser: N/A (crash happens before the UI is opened)
• Tor status: always (--tor always)
• Opened port: no
• Special configuration: Started via start-venv.sh with flags --tor always --no-dht. System tray (Trayicon plugin) enabled, X11 session with DISPLAY=:1. pystray and python-xlib installed in the venv.

Step 2: Describe the problem

When starting EpixNet with --tor always, the Trayicon plugin crashes the whole process at startup because the global socket.socket has been replaced with socks.socksocket by src/util/SocksProxy.py:monkeyPatch. pystray's xorg backend imports Xlib, which then tries to open the X server connection through the SOCKS-patched socket. Unix-domain X11 sockets aren't supported by PySocks, and the TCP fallback fails because there's no destination configured for a local X server connection, so EpixNet exits.

Steps to reproduce

1. On Linux with an X11 session (e.g. DISPLAY=:1), set up the venv and install requirements.
2. Make sure pystray and python-xlib are installed (they're pulled in for the system tray).
3. Run ./start-venv.sh (which launches python3 epixnet.py --tor always --no-dht).
4. EpixNet patches sockets to the Tor SOCKS proxy, then the Trayicon plugin tries to create the tray icon.

Observed Results

EpixNet crashes at startup with the following traceback:

[21:27:52] - Patching sockets to tor socks proxy: 127.0.0.1:9050
[21:27:52] - epixnet 0.2.7 (source from main-fc3486d8f9e5196870aa451531cf4712a213ed02-dirty) on Python 3.12.3 ... Gevent 26.4.0
[21:27:52] - Unhandled exception: Can't connect to display ":1": Invalid destination-connection (host, port) pair
Traceback (most recent call last):
  File ".../Xlib/support/unix_connect.py", line 104, in get_socket
    s = _get_unix_socket(address)
  File ".../Xlib/support/unix_connect.py", line 82, in _get_unix_socket
    s.connect(address)
  File ".../socks.py", line 742, in connect
    raise socket.error("PySocks doesn't support IPv6: %s"
OSError: PySocks doesn't support IPv6: /tmp/.X11-unix/X1

During handling of the above exception, another exception occurred:
  File ".../Xlib/support/unix_connect.py", line 76, in _get_tcp_socket
    s.connect((host, 6000 + dno))
  File ".../socks.py", line 769, in connect
    raise GeneralProxyError(...)
socks.GeneralProxyError: Invalid destination-connection (host, port) pair

During handling of the above exception, another exception occurred:
  File ".../plugins/Trayicon/TrayiconPlugin.py", line 205, in main
    self.icon = pystray.Icon(...)
  File ".../pystray/_xorg.py", line 107, in __init__
    self._display = Xlib.display.Display()
  ...
Xlib.error.DisplayConnectionError: Can't connect to display ":1": Invalid destination-connection (host, port) pair

Exception ignored in: <function Icon.__del__ at ...>
AttributeError: 'Icon' object has no attribute '_display'

Root cause: src/util/SocksProxy.py:monkeyPatch replaces socket.socket with socks.socksocket globally. When pystray._xorg later constructs Xlib.display.Display() (both during import and inside Icon.__init__ / Icon.run), Xlib.support.unix_connect calls socket.socket(AF_UNIX, ...) to talk to /tmp/.X11-unix/X*. PySocks rejects the AF_UNIX address (PySocks doesn't support IPv6) and the TCP fallback to localhost:6001 fails too (Invalid destination-connection (host, port) pair).

Expected Results

When --tor always is set on a Linux desktop with a system tray, EpixNet should still start normally and show its tray icon. X11 connections to the local display should never be routed through the Tor SOCKS proxy. If the X display genuinely cannot be opened (truly headless), the Trayicon plugin should log a warning and continue without a tray icon instead of crashing the entire process.

Suggested fix

In plugins/Trayicon/TrayiconPlugin.py, before importing/initializing pystray, restore the original socket class (saved by SocksProxy.monkeyPatch as socket.socket_noproxy) and patch the socket module reference inside Xlib.support.unix_connect, Xlib.support.connect, and Xlib.protocol.display with a shim whose .socket attribute is socket.socket_noproxy. This keeps the global SOCKS patch in place for normal network traffic but ensures Xlib's local X11 connections always use the unproxied socket. Also wrap the pystray initialization in a generic except Exception so a missing/unreachable display degrades gracefully instead of crashing EpixNet.

Suggested patch

Applied to plugins/Trayicon/TrayiconPlugin.py, inside ActionsPlugin.main(), replacing the original try: import pystray ... block:

    def main(self):
        # SocksProxy.monkeyPatch may have replaced socket.socket with
        # socks.socksocket, which doesn't support AF_UNIX. Xlib (used by
        # pystray's xorg backend) connects to /tmp/.X11-unix/X* via AF_UNIX,
        # so temporarily restore the real socket while pystray initializes.
        import socket
        _patched_socket = None
        if hasattr(socket, "socket_noproxy"):
            _patched_socket = socket.socket
            socket.socket = socket.socket_noproxy
        try:
            try:
                import pystray
                import pystray._base
                from PIL import Image
            except ImportError as err:
                print("Trayicon plugin: pystray or Pillow not installed (%s), skipping tray icon." % err)
                super(ActionsPlugin, self).main()
                return
            except Exception as err:
                print("Trayicon plugin: failed to initialize tray icon backend (%s), skipping tray icon." % err)
                super(ActionsPlugin, self).main()
                return

            # pystray's xorg backend opens (and uses) the X display lazily
            # inside Icon.__init__ / Icon.run, long after this function
            # returns. Patch Xlib's module-level `socket` references with a
            # shim that exposes the un-proxied socket class, so X11
            # connections never go through PySocks.
            if _patched_socket is not None:
                try:
                    import types
                    shim = types.ModuleType("socket_noproxy_shim")
                    for _name in dir(socket):
                        try:
                            setattr(shim, _name, getattr(socket, _name))
                        except AttributeError:
                            pass
                    shim.socket = socket.socket_noproxy
                    for _modname in (
                        "Xlib.support.unix_connect",
                        "Xlib.support.connect",
                        "Xlib.protocol.display",
                    ):
                        _mod = sys.modules.get(_modname)
                        if _mod is not None and hasattr(_mod, "socket"):
                            _mod.socket = shim
                except Exception as err:
                    print("Trayicon plugin: failed to patch Xlib socket: %s" % err)
        finally:
            if _patched_socket is not None:
                socket.socket = _patched_socket

What this does:

1. Temporarily un-patches socket.socket while pystray (and transitively Xlib) is imported, so the import-time Xlib.display.Display() call in pystray/_xorg.py succeeds.
2. Installs a socket shim into the loaded Xlib modules (Xlib.support.unix_connect, Xlib.support.connect, Xlib.protocol.display). The shim mirrors the real socket module but exposes socket.socket_noproxy as its .socket class. This is necessary because pystray._xorg.Icon.__init__ opens its own Xlib.display.Display() later, in the trayicon thread — long after main() returns — and that call must also bypass PySocks.
3. Restores the global socket.socket (= socks.socksocket) in finally, so all other EpixNet/Gevent network traffic continues to be routed through the Tor SOCKS proxy as before.
4. Adds a generic except Exception around the pystray import so a truly unavailable display (headless server, Wayland-only, etc.) just logs a warning and continues without a tray icon, instead of taking the whole process down.

No other files are modified, and the change is a no-op when --tor always is not in use (because socket.socket_noproxy only exists after SocksProxy.monkeyPatch has run).