WIP: initial step towards websocket-based remote card [reader] access

Change-Id: I588bf4b3d9891766dd688a6818057ca20fb26e3f

pySim/transport/wsrc.py

@@ -0,0 +1,101 @@
+# Copyright (C) 2024  Harald Welte <laforge@gnumonks.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+import argparse
+from typing import Optional
+
+from osmocom.utils import h2i, i2h, Hexstr, is_hexstr
+
+from pySim.exceptions import NoCardError, ProtocolError, ReaderError
+from pySim.transport import LinkBase
+from pySim.utils import ResTuple
+from pySim.wsrc.client_blocking import WsClientBlocking
+
+class UserWsClientBlocking(WsClientBlocking):
+    def perform_outbound_hello(self):
+        hello_data = {
+            'client_type': 'user',
+        }
+        super().perform_outbound_hello(hello_data)
+
+    def select_card(self, id_type:str, id_str:str):
+        rx = self.transceive_json('select_card', {'id_type': id_type, 'id_str': id_str},
+                                  'select_card_ack')
+        return rx
+
+    def reset_card(self):
+        self.transceive_json('reset_req', {}, 'reset_resp')
+
+    def xceive_apdu_raw(self, cmd: Hexstr) -> ResTuple:
+        rx = self.transceive_json('c_apdu', {'command': cmd}, 'r_apdu')
+        return rx['response'], rx['sw']
+
+
+class WsrcSimLink(LinkBase):
+    """ pySim: WSRC (WebSocket Remote Card) reader transport link."""
+    name = 'WSRC'
+
+    def __init__(self, opts: argparse.Namespace, **kwargs):
+        super().__init__(**kwargs)
+        self.identities = {}
+        self.server_url = opts.wsrc_server_url
+        if opts.wsrc_eid:
+            self.id_type = 'eid'
+            self.id_str = opts.wsrc_eid
+        elif opts.wsrc_iccid:
+            self.id_type = 'iccid'
+            self.id_str = opts.wsrc_iccid
+        self.client = UserWsClientBlocking(self.server_url)
+        self.client.connect()
+
+    def __del__(self):
+       # FIXME: disconnect from server
+       pass
+
+    def wait_for_card(self, timeout: Optional[int] = None, newcardonly: bool = False):
+        self.connect()
+
+    def connect(self):
+        rx = self.client.select_card(self.id_type, self.id_str)
+        self.identitites = rx['identities']
+
+    def get_atr(self) -> Hexstr:
+        return self.identities['atr']
+
+    def disconnect(self):
+        self.__delete__()
+
+    def _reset_card(self):
+        self.client.reset_card()
+        return 1
+
+    def _send_apdu_raw(self, pdu: Hexstr) -> ResTuple:
+        return self.client.xceive_apdu_raw(pdu)
+
+    def __str__(self) -> str:
+        return "WSRC[%s=%s]" % (self.id_type, self.id_str)
+
+    @staticmethod
+    def argparse_add_reader_args(arg_parser: argparse.ArgumentParser):
+        wsrc_group = arg_parser.add_argument_group('WebSocket Remote Card',
+            """WebSocket Remote Card (WSRC) is a protoocl by which remot cards / card readers
+            can be accessed via a network.""")
+        wsrc_group.add_argument('--wsrc-server-url',
+                                help='URI of the WSRC server to connect to')
+        wsrc_group.add_argument('--wsrc-iccid', type=is_hexstr,
+                                help='ICCID of the card to open via WSRC')
+        wsrc_group.add_argument('--wsrc-eid', type=is_hexstr,
+                                help='EID of the card to open via WSRC')