simtrac hw

[ml at mail.tsaitgaist.info]

thanks for the feedback and recommendations

I added the JTAG and debug connectors. I hope it will not use more then
2 layers in the end, so normal people can build the pcb at home.

I could not login/register on the osmocom trac wiki to put the files
there. Here the current version :
https://gsm.tsaitgaist.info/SIMtrac/v0.2/trac.ps
I now use this direct link (it could take some time until the DN is
spread over all DNS)

I did not yet add the MiM solution, because there are still have some
open aspects :
MiM :
- should it use the clock provider by the reader
- or should we provided our own clock (3.8432MHz/9600bps for simplicity)
using the reader clock would provide better timing but cold be harder to
do (I don't know well this chip yet)

emulation :
- how to know what the user wants (sniff vs emulation) if the mode is
combined with the sniffer ?
- the user has to tell the program
- or by detecting the presence of a card (provided by the id-1 socket,
but some tricks have to be used for the id-000 socket)
- or by having a switch with 3 modes (sniff,emulation,MiM) (my favorite
solution)

I did a very simple PCB just to test the sniffer. I will take time to
get a good design for the promising SIMtrac.

kevin

On 21.11.2010 20:53, Harald Welte wrote:
> Hi!
> 
> On Sun, Nov 21, 2010 at 03:14:34PM +0100, ml at mail.tsaitgaist.info wrote:
> 
>> His solution is way easier, and more reliable. This is why I've now done
>> a hw design for it.
> 
> thanks a lot.
> 
>> I don't know if it's the right mailing list, but it seemed to be the best.
> 
> well, I think it is low-traffic and we might just use this mailing list
> for the time being.
> 
>> - the AT91SAM7SXXX
>> - 2 SC sockets (ID-1 and ID-000) for the SIM in credit card and usual
>> size, as on the rebelSIM
>> - 1 SC port (IN) to connect the SIM for the phone (I would use the ones
>> from rebelSIM)
>> - 1 SC port (OUT) to be able to use the signal using external HW
>> - the sam-ba port to be able to flash it
> 
> I think we should consider the following use cases:
> 
> 1) passive sniffer
> 
> this is what simtrace is doing right now and what your hardware is also
> prepared for. 
> 
> 2) card simulation
> 
> this is possible with the same circuit.  Simply connect it _only_ to
> the phone and not to a smart card at all.  The wiring will be the same,
> but the USART will be used in Rx and Tx mode.  Only software/firmware
> changes required.
> 
> 3) man in the middle
> 
> in this case, we want to connect as master (reader) to the SIM card,
> and as slave (card-side interface) to the phone.
> 
> In order to make we run USART0 as clock-slave (like in case 1 + 2 above),
> but we also connect a sim card socket to USART1, which we can then run
> in clock-master mode, i.e. like any 'regular' SAM7 based smart card reader.
> 
> The easiest solution would be to add yet another sim card socket which is
> connected to USART1 (TXD1/SCK1).  But then we have 3-4 sim card sockets
> in one device, which I think is clumsy.
> 
> It may be possible to add some jumpers or dip switches that change the
> behavior, i.e. "one setting for sniffer + card simluation, another setting for
> man-in-the-middle"
> 
>> here the schema : https://file.tsaitgaist.info/www/?a=d&i=CWn6xIaCVe
>> please tell me if there is something wrong, or needs some improvement. I
>> will design the PCB shortly.
> 
> please take time for detailed review before doign any pcbs... thinking more
> before prototyping will save time and money.
> 
> Another request: Pleaes make the DRxD / DTxD (Debug UART) pins available on the
> board, preferrably on the same type of header that we use on the OpenPCD.  It
> will not add any cost to the design, but enable you to print debug messages to
> a serial port, which is very useful during firmware development.
> 
> Also, the JTAG lines should be routed to a standard 20-pin ARM-JTAG connector.
> 
> Both the Debug-UART and the JTAG headers can not be placed/soldered for normal
> boards, but people who want to do development will likely find both of them
> very useful.
> 
> Regards,
> 	Harald