vm: add run_with_args method to call a single command with specific arguments

The method will ensure the parameters are properly handled as actual
separate arguments, regardless of shell special characters in them.
For now implement this with shlex.quote, later dedicated qrexec service
could be used.

QubesOS/qubes-issues#4850

qubesadmin/vm/__init__.py

@@ -21,6 +21,7 @@
 '''Qubes VM objects.'''
 
 import logging
+import shlex
 
 import subprocess
 import warnings
@@ -305,6 +306,15 @@ class QubesVM(qubesadmin.base.PropertyHolder):
             e.cmd = command
             raise e
 
+    def run_with_args(self, *args, **kwargs):
+        '''Run a single command inside the domain using qubes.VMShell qrexec.
+
+        This method execute a single command, without interpreting any shell
+        special characters.
+
+        '''  # pylint: disable=redefined-builtin
+        return self.run(' '.join(shlex.quote(arg) for arg in args), **kwargs)
+
     @property
     def appvms(self):
         ''' Returns a generator containing all domains based on the current