From 7858f591fec4047a8083f9a837183589f76fc1ad Mon Sep 17 00:00:00 2001 From: Philipp Maier Date: Thu, 25 Jul 2024 12:20:27 +0200 Subject: [PATCH] pySim-shell: turn "ADF-escape-code" into an lchan method. When we traverse the file system using the command "export" we will also select all ADFs but not all ADFs may have UICC file system support. This makes it impossible to exit those ADFs again. To exit anyway we select an application with filesystem support first and then the parent EF we wanted to select originally. This method may not only be useful when traversing the filesystem, so let's put it into the RuntimeLchan class and change it a little so that it would also work if the ADF in question is an a sub DF. Related: OS#6092 Change-Id: I72de51bc7519fafbcc71d829719a8af35d774342 --- pySim-shell.py | 27 +-------------------------- pySim/runtime.py | 30 ++++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+), 26 deletions(-) diff --git a/pySim-shell.py b/pySim-shell.py index 4f5959b3..2eb37ea7 100755 --- a/pySim-shell.py +++ b/pySim-shell.py @@ -535,32 +535,7 @@ class PySimCommands(CommandSet): # below, so we must not move up. if skip_df == False: self.walk(indent + 1, action_ef, action_df, context, **kwargs) - - parent = self._cmd.lchan.selected_file.parent - df = self._cmd.lchan.selected_file - adf = self._cmd.lchan.selected_adf - if isinstance(parent, CardMF) and (adf and adf.has_fs == False): - # Not every application that may be present on a GlobalPlatform card will support the SELECT - # command as we know it from ETSI TS 102 221, section 11.1.1. In fact the only subset of - # SELECT we may rely on is the OPEN SELECT command as specified in GlobalPlatform Card - # Specification, section 11.9. Unfortunately the OPEN SELECT command only supports the - # "select by name" method, which means we can only select an application and not a file. - # The consequence of this is that we may get trapped in an application that does not have - # ISIM/USIM like file system support and the only way to leave that application is to select - # an ISIM/USIM application in order to get the file system access back. - # - # To automate this escape-route while traversing the file system we will check whether - # the parent file is the MF. When this is the case and the selected ADF has no file system - # support, we will select an arbitrary ADF that has file system support first and from there - # we will then select the MF. - for selectable in parent.get_selectables().items(): - if isinstance(selectable[1], CardADF) and selectable[1].has_fs == True: - self._cmd.lchan.select(selectable[1].name, self._cmd) - break - self._cmd.lchan.select(df.get_mf().name, self._cmd) - else: - # Normal DF/ADF selection - fcp_dec = self._cmd.lchan.select("..", self._cmd) + self._cmd.lchan.select_parent(self._cmd) elif action_ef: df_before_action = self._cmd.lchan.selected_file diff --git a/pySim/runtime.py b/pySim/runtime.py index a56d8843..a56df4d1 100644 --- a/pySim/runtime.py +++ b/pySim/runtime.py @@ -396,6 +396,36 @@ class RuntimeLchan: return self.selected_file_fcp + def select_parent(self, cmd_app=None): + """Select the parent file of the currently selected file. This method also works in case the currently selected + file is an ADF without UICC file system support and can be used to exit those ADFs. + """ + parent = self.selected_file.parent + df = self.selected_file + adf = self.selected_adf + if adf and adf.has_fs == False: + # Not every application that may be present on a GlobalPlatform card will support the SELECT + # command as we know it from ETSI TS 102 221, section 11.1.1. In fact the only subset of + # SELECT we may rely on is the OPEN SELECT command as specified in GlobalPlatform Card + # Specification, section 11.9. Unfortunately the OPEN SELECT command only supports the + # "select by name" method, which means we can only select an application and not a file. + # The consequence of this is that we may get trapped in an application that does not have + # ISIM/USIM like file system support and the only way to leave that application is to select + # an ISIM/USIM application in order to get the file system access back. + # + # To automate this escape-route while traversing the file system we will check whether + # the parent file is the MF. When this is the case and the selected ADF has no file system + # support, we will select an arbitrary ADF that has file system support first and from there + # we will then select the MF. + for selectable in parent.get_selectables().items(): + if isinstance(selectable[1], CardADF) and selectable[1].has_fs == True: + self.select(selectable[1].name, cmd_app) + break + self.select_file(parent, cmd_app) + + # Select the parent file normally + self.select_file(parent, cmd_app) + def status(self): """Request STATUS (current selected file FCP) from card.""" (data, _sw) = self.scc.status()