Hi Thomas, On Thu, Nov 09, 2017 at 08:59:45PM -0500, Thomas Chen wrote: > my understand of the protocol is that > > ME => SIM (first 5 bytes of APDU) > > SIM <=== PROCEDURE (either INS as ack, or 0x60 to hold up the protocol) > > but that does not help remote sim, as remote SIM would need the susequent > bytes > which will not come until we send back INS, so just holding off ME with 0x60 > does not alleviate the problem of network delay
you don't hold off the ME at that point. Presuming it is "RUN GSM ALGORITHM" command, then the actual command from ME to card continues here with the random challenge. Later, a GET RESPONSE is issued from ME to SIM to obtain the SRES + Kc values, and this is where we can delay with waiting time extension (0x60) until we have the result. -- - Harald Welte <[email protected]> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)
