nixos/scripts/greeter-check.py

"""Test greeter failure/retry/launch against a fake greetd server.

Usage: QML2_IMPORT_PATH=<qt5compat>/lib/qt-6/qml python3 scripts/greeter-check.py <auth-bundle>
Requires qs on PATH. No real authentication or desktop launch occurs.
"""

import json, os, socket, struct, subprocess as sp, tempfile, time, shutil, sys
from pathlib import Path

qs = shutil.which("qs")
assert qs, "qs must be on PATH"
root = Path(tempfile.mkdtemp(prefix="fred-greetd-check."))
root.chmod(0o700)
shutil.copytree(str(Path(sys.argv[1]) / "greeter"), root / "config")
p = root / "config/shell.qml"
p.chmod(0o600)
s = (
    p.read_text()
    .replace("import Quickshell\n", "import Quickshell\nimport Quickshell.Io\n")
    .replace("    AuthView {", "    AuthView {\n        id: auth")
)
s = (
    s.rstrip()[:-1]
    + """    IpcHandler { target: "test"; function submit(password: string): void { auth.submitted(password); } }
}
"""
)
p.write_text(s)
server = socket.socket(socket.AF_UNIX)
server.bind(str(root / "greetd.sock"))
server.listen()
server.settimeout(10)
env = {
    **os.environ,
    "HOME": str(root),
    "XDG_RUNTIME_DIR": str(root),
    "GREETD_SOCK": str(root / "greetd.sock"),
    "FRED_GREETER": "1",
    "QT_QPA_PLATFORM": "offscreen",
    "QT_QUICK_BACKEND": "software",
    "FRED_SESSION_COMMAND": "/fixture/authenticated-session",
}
log = open(root / "log", "w")
proc = sp.Popen([qs, "-p", str(root / "config")], env=env, stdout=log, stderr=log)
try:
    conn, _ = server.accept()
    conn.settimeout(5)

    def recv():
        data = b""
        while len(data) < 4:
            data += conn.recv(4 - len(data))
        size = struct.unpack("<I", data)[0]
        data = b""
        while len(data) < size:
            data += conn.recv(size - len(data))
        value = json.loads(data)
        print(value, flush=True)
        return value

    def send(value):
        data = json.dumps(value).encode()
        conn.sendall(struct.pack("<I", len(data)) + data)

    def submit():
        for _ in range(30):
            result = sp.run(
                [
                    qs,
                    "ipc",
                    "--pid",
                    str(proc.pid),
                    "call",
                    "test",
                    "submit",
                    "fixture-password",
                ],
                env=env,
                capture_output=True,
                text=True,
            )
            if result.returncode == 0:
                return
            time.sleep(0.1)
        raise AssertionError(result.stderr)

    for success in [False, True]:
        submit()
        assert recv() == {"type": "create_session", "username": "fred"}
        send(
            {
                "type": "auth_message",
                "auth_message_type": "secret",
                "auth_message": "Password:",
            }
        )
        assert recv() == {
            "type": "post_auth_message_response",
            "response": "fixture-password",
        }
        if success:
            send({"type": "success"})
            launch = recv()
            assert (
                launch["type"] == "start_session"
                and launch["cmd"] == ["/fixture/authenticated-session"]
                and "XDG_SESSION_TYPE=wayland" in launch["env"]
            )
            send({"type": "success"})
            assert proc.wait(timeout=5) == 0
        else:
            send(
                {
                    "type": "error",
                    "error_type": "auth_error",
                    "description": "fixture rejection",
                }
            )
            assert recv() == {"type": "cancel_session"}
            send({"type": "success"})
            time.sleep(0.3)
    print(
        "Greeter: failed password does not launch; retry and authenticated launch pass"
    )
finally:
    proc.terminate()
    proc.wait()
    log.close()
    print((root / "log").read_text())