test_cryptowrapper: add some basic tests for crypto-wrapper

It tests only if hardware type is correctly reported and if appropriate
serial number is returned.

This adds new requirement for configuration and that is serial number.
We need this to verify that crypto-wrapper correctly returns appropriate
number.

nsfarm/target/target.py

@@ -32,6 +32,7 @@ class Target:
         """
         return bool(
             self.board and self.board in BOARDS and
+            self.serial_number and len(self.serial_number) == 16 and
             self.serial and
             self.wan
         )
@@ -62,6 +63,12 @@ class Target:
         """
         return self._conf.get("board")
 
+    @property
+    def serial_number(self) -> str:
+        """Serial number of target board.
+        """
+        return self._conf.get("serial_number")
+
     @property
     def serial(self) -> str:
         """Serial interface connected to target board.

targets.example.ini

@@ -20,6 +20,8 @@
 # * omnia (for Turris Omnia)
 # * turris1x (for Turris 1.0 and 1.1)
 board = omnia
+# Serial number of board in hex format (all 16 characters)
+serial_number = 0000000000000000
 # This is path to serial TTY. It is suggested to use /dev/serial/by-path/* device
 # over /dev/tty* as path is preserved between reboots but device identifier not.
 # On the other hand there is no other problem with using /dev/ttyUSB0 and for

tests/tests_cryptowrapper.py

+"""These are tests to check that we are able to communicate with board's crypto.
+The backend is different depending on board but common crypto-wrapper unites the
+attribute access.
+"""
+import pytest
+
+
+@pytest.mark.parametrize("hwtype", [
+    pytest.param("atsha", marks=pytest.mark.board("omnia", "turris1x")),
+    pytest.param("otp", marks=pytest.mark.board("mox")),
+])
+def test_hw_type(hwtype, client_board):
+    """Check if reported hardware type matches board.
+    """
+    client_board.run("crypto-wrapper hw-type")
+    assert client_board.output == hwtype
+
+
+def test_serial_number(request, client_board):
+    """Check that syslog-ng is running by checking if there is /var/log/messages (default log output).
+    """
+    client_board.run("crypto-wrapper serial-number")
+    assert client_board.output == request.config.target_config.serial_number