* device list as explicit list

src/cryptobox/core/settings.py

@@ -561,7 +561,7 @@ class CryptoBoxSettings:
 
     validation_spec = """
 [Main]
-AllowedDevices = list(min=1)
+AllowedDevices = listOfDevices(default="")
 DefaultVolumePrefix = string(min=1)
 DefaultCipher = string(default="aes-cbc-essiv:sha256")
 ConfigVolumeLabel = string(min=1, default="cbox_config")
@@ -625,6 +625,7 @@ class CryptoBoxSettingsValidator(validate.Validator):
         self.functions["fileWriteable"] = self.check_file_writeable
         self.functions["listOfExistingDirectories"] = self.check_existing_directories
         self.functions["listOfLanguages"] = self.list_languages
+        self.functions["listOfDevices"] = self.list_devices
     
 
     def check_directory_exists(self, value):
@@ -692,6 +693,16 @@ class CryptoBoxSettingsValidator(validate.Validator):
             langs = [langs]
         return langs
 
+    def list_devices(self, devices):
+        """Return devices as a list.
+        """
+        if not devices:
+            raise validate.VdtValueError("no device specified")
+        if not isinstance(devices, list):
+            devices = [devices]
+        return devices
+
+
 
 class MiscConfigFile:
     """all other config files (e.g. a ssl certificate) to be stored"""