CardKeyProvider: Implement support for column-based transport key encryption

It's generally a bad idea to keep [card specific] key material lying
around unencrypted in CSV files.  The industry standard solution in the
GSMA is a so-called "transport key", which encrypts the key material.

Let's introduce support for this in the CardKeyProvider (and
specifically, the CardKeyProviderCSV) and allow the user to specify
transport key material as command line options to pySim-shell.

Different transport keys can be used for different key materials, so
allow specification of keys on a CSV-column base.

The higher-level goal is to allow the CSV file not only to store
the ADM keys (like now), but also global platform key material for
establishing SCP towards various security domains in a given card.

Change-Id: I13146a799448d03c681dc868aaa31eb78b7821ff

pySim-shell.py

@@ -967,6 +967,8 @@ global_group.add_argument('--script', metavar='PATH', default=None,
                           help='script with pySim-shell commands to be executed automatically at start-up')
 global_group.add_argument('--csv', metavar='FILE',
                           default=None, help='Read card data from CSV file')
+global_group.add_argument('--csv-column-key', metavar='FIELD:AES_KEY_HEX', default=[], action='append',
+                          help='per-CSV-column AES transport key')
 global_group.add_argument("--card_handler", dest="card_handler_config", metavar="FILE",
                           help="Use automatic card handling machine")
 
@@ -993,13 +995,18 @@ if __name__ == '__main__':
             print("Invalid script file!")
             sys.exit(2)
 
+    csv_column_keys = {}
+    for par in opts.csv_column_key:
+        name, key = par.split(':')
+        csv_column_keys[name] = key
+
     # Register csv-file as card data provider, either from specified CSV
     # or from CSV file in home directory
     csv_default = str(Path.home()) + "/.osmocom/pysim/card_data.csv"
     if opts.csv:
-        card_key_provider_register(CardKeyProviderCsv(opts.csv))
+        card_key_provider_register(CardKeyProviderCsv(opts.csv, csv_column_keys))
     if os.path.isfile(csv_default):
-        card_key_provider_register(CardKeyProviderCsv(csv_default))
+        card_key_provider_register(CardKeyProviderCsv(csv_default, csv_column_keys))
 
     # Init card reader driver
     sl = init_reader(opts, proactive_handler = Proact())