Hi Marc,
On Wed, Sep 28, 2022 at 11:17:57AM +0000, Marc Wilson wrote:
I have observed several instances where commands/traffic issued by the SIM are not implemented (seemingly not received) by the modem whilst utilising the RemSIM connection.
I'm sorry to hear.
Two examples I have recorded are of a UICC reset (refresh type '03' (= NAA Initialization)) and of a proactive 'open channel' command.
Is this something that you would expect within the application (essentially a single 'initiation' traffic flow - modem to card but not card to modem)?
No, this is certainly not expected. The osmo-remsim software and the RSPRO protocol are designed to transparently pass T=0 TPDUs between reader/modem and card.
IT doesn't matter if the logical initiator of the communication on application level is in the modem (classic SIM access) or in the card (proactive SIM). On the ISO7816-3 layer on which we operate those are all just TPDUs. The modem is polling the card periodically for proactive commands, and if any are pending the modem will fetch them via FETCH. The TPDU structure is always the same.
I'd definitely be interested to hear more about the bug you are observing. Ideally we'd review a RSPRO pcap file and log file output of the osmo-remsim-{client,bankd}.
Regards, Harald