Improve Nitrokey Start upgrade process

pynitrokey/cli/start.py

@@ -7,7 +7,9 @@
 # http://opensource.org/licenses/MIT>, at your option. This file may not be
 # copied, modified, or distributed except according to those terms.
 
-
+import fnmatch
+import os
+import os.path
 from subprocess import check_output
 from sys import stderr, stdout
 from time import sleep
@@ -16,7 +18,7 @@
 from tqdm import tqdm
 from usb.core import USBError
 
-from pynitrokey.helpers import local_critical, local_print
+from pynitrokey.helpers import confirm_keyboard_interrupt, local_critical, local_print
 from pynitrokey.start.gnuk_token import get_gnuk_device
 from pynitrokey.start.threaded_log import ThreadLog
 from pynitrokey.start.upgrade_by_passwd import (
@@ -164,6 +166,12 @@ def set_identity(identity):
     default=False,
     help="Use firmware for early 'Nitrokey Start' key hardware revisions",
 )
+@click.option(
+    "--force",
+    is_flag=True,
+    default=False,
+    help="Execute the firmware update even if environment sanity checks fail",
+)
 def update(
     regnual,
     gnuk,
@@ -175,9 +183,24 @@ def update(
     yes,
     skip_bootloader,
     green_led,
+    force,
 ):
     """update device's firmware"""
 
+    if not find_udev_rules():
+        if force:
+            local_print(
+                "Warning: Could not find Nitrokey udev rules but will continue anyway as --force is set."
+            )
+        else:
+            local_critical(
+                "Failed to find Nitrokey udev rules.  These udev rules are required for the update.",
+                "Please see the nitropy documentation for information on installing these rules:",
+                "    https://docs.nitrokey.com/software/nitropy/linux/udev.html",
+                "If you want to continue anyway, you can use the --force option.",
+                support_hint=False,
+            )
+
     args = (
         regnual,
         gnuk,
@@ -198,11 +221,28 @@ def update(
             "use one from: https://github.com/Nitrokey/nitrokey-start-firmware)",
         )
 
-    if IS_LINUX:
-        with ThreadLog(logger.getChild("dmesg"), "dmesg -w"):
+    with confirm_keyboard_interrupt("Cancelling the update may brick your device."):
+        if IS_LINUX:
+            with ThreadLog(logger.getChild("dmesg"), "dmesg -w"):
+                start_update(*args)
+        else:
             start_update(*args)
-    else:
-        start_update(*args)
+
+
+def find_udev_rules() -> bool:
+    dirs = [
+        "/usr/lib/udev/rules.d",
+        "/usr/local/lib/udev/rules.d",
+        "/run/udev/rules.d",
+        "/etc/udev/rules.d",
+    ]
+    for d in dirs:
+        if os.path.isdir(d):
+            for name in os.listdir(d):
+                if fnmatch.fnmatch(name, "??-nitrokey.rules"):
+                    logger.info(f"Found matching udev file at {os.path.join(d, name)}")
+                    return True
+    return False
 
 
 @click.command()

pynitrokey/helpers.py

@@ -12,12 +12,14 @@
 import logging
 import os
 import platform
+import signal
 import sys
 import time
+from contextlib import contextmanager
 from getpass import getpass
 from numbers import Number
 from threading import Event, Timer
-from typing import List, Optional
+from typing import Any, Iterator, List, Optional
 
 import click
 from tqdm import tqdm
@@ -351,6 +353,33 @@ def ask(self):
 prompt = functools.partial(click.prompt, err=True)
 
 
+@contextmanager
+def confirm_keyboard_interrupt(msg: Optional[str] = None) -> Iterator[None]:
+    """
+    Registers a signal handler for SIGINT (i. e. Ctrl+C) that asks the user to confirm before
+    raising a KeyboardInterrupt.
+
+    If used as a context manager, it resets the signal handler after the execution.  The given
+    message is appended to the confirmation prompt.
+    """
+
+    def handle_sigint(signum: int, frame: Any) -> None:
+        text = "Do you really want to stop nitropy?"
+        if msg:
+            text += " "
+            text += msg
+        if confirm(text):
+            raise KeyboardInterrupt
+
+    handler = signal.signal(signal.SIGINT, handle_sigint)
+    try:
+        yield
+    except Exception:
+        raise
+    finally:
+        signal.signal(signal.SIGINT, handler)
+
+
 def require_windows_admin() -> None:
     if os.name == "nt":
         if ctypes.windll.shell32.IsUserAnAdmin() == 0:  # type: ignore

pynitrokey/start/upgrade_by_passwd.py

@@ -279,15 +279,15 @@ def get_latest_release_data():
     try:
         # @todo: move to confconsts.py
         r = requests.get(
-            "https://api.github.com/repos/Nitrokey/nitrokey-start-firmware/releases"
+            "https://api.github.com/repos/Nitrokey/nitrokey-start-firmware/releases/latest"
         )
         json = r.json()
         if r.status_code == 403:
             local_critical(
                 f"JSON raw data: {json}",
                 f"No Github API access, status code: {r.status_code}",
             )
-        latest_tag = json[0]
+        latest_tag = json
 
     except Exception as e:
         local_critical("Failed getting release data", e)
@@ -590,6 +590,7 @@ def start_update(
         "- all data will be removed from the device!",
         "- do not interrupt update process - the device may not run properly!",
         "- the process should not take more than 1 minute",
+        "- if the update fails, do not remove the device! Repeat the update instead.",
     )
     if yes:
         local_print("Accepted automatically")
@@ -651,9 +652,9 @@ def start_update(
             "",
             "Could not proceed with the update",
             "Please execute one or all of the following and try again:",
-            "- re-insert device to the USB slot",
             "- run factory-reset on the device",
             "- close other applications, which could use it (e.g., scdaemon, pcscd)",
+            "- repeat the update",
         )
 
     dev_strings_upgraded = None
@@ -662,7 +663,10 @@ def start_update(
     for i in range(TIME_DETECT_DEVICE_AFTER_UPDATE_S):
         if i > TIME_DETECT_DEVICE_AFTER_UPDATE_LONG_S:
             if not takes_long_time:
-                local_print("", "Please reinsert device to the USB slot")
+                local_print(
+                    "",
+                    "If you have removed the device, please reinsert it to the USB slot",
+                )
                 takes_long_time = True
         time.sleep(1)
         dev_strings_upgraded = get_devices()
@@ -673,11 +677,12 @@ def start_update(
         local_print(".", end="", flush=True)
 
     if not dev_strings_upgraded:
-        local_print(
+        local_critical(
             "",
             "could not connect to the device - might be due to a failed update",
-            "please re-insert the device, check version using:",
+            "please check the device version with:",
             "$ nitropy start list",
+            "and repeat the update if necessary",
         )
 
     local_print(