Reader attribute SCARD_ATTR_VENDOR_IFD_SERIAL_NO missing last byte

[palu3492]

I'm using an OMNIKEY 5427 CK reader and I'm having problems getting the serial number of the reader when using getAttrib on the reader connection. It seems to be short a byte. When I use the "OMNIKEY Specific Commands" and send an APDU command to the "Reader Information API" for the reader serial number, I get the correct serial number. Here are my code and output.

reader = readers()[0]
connection = reader.createConnection()
connection.connect()
# OMNIKEY Reader Information API
serial_number_apdu = [255, 112, 7, 107, 8, 162, 6, 160, 4, 160, 2, 146, 0, 0]
data, sw1, sw2 = connection.transmit(serial_number_apdu)
sn = toHexString(data[6:], PACK)
print(sn)

sn = connection.getAttrib(SCARD_ATTR_VENDOR_IFD_SERIAL_NO)
sn = hl2bs(sn)
print(sn)

Out:

010100534310112202019E563430630
010100534310112202019E56343063

The OMNIKEY web interface to my reader also shows the serial number with a trailing zero.

[LudovicRousseau]

What operating system do you use?

[palu3492]

Ubuntu 16.04 virtual machine on Mac.

[LudovicRousseau]

The serial number reported by SCARD_ATTR_VENDOR_IFD_SERIAL_NO comes from the USB descriptor. You should be able to see it using lsusb -v | grep iSerial. What do you get in that case?

I did not know if was also possible to get the device serial number using an APDU.

[palu3492]

$ lsusb -vd 076b:5427 | grep iSerial
iSerial  3  010100534310112202019E563430630

It indeed shows the device's serial number as having a zero at the end.

[LudovicRousseau]

So that is strange. I will have a look.

[LudovicRousseau]

Can you generate a pcscd log as documented at https://pcsclite.apdu.fr/#support ?

[LudovicRousseau]

Can you also use print(reader) in your code and copy the result?

The serial number should be in the PC/SC reader name. https://ludovicrousseau.blogspot.com/2010/05/what-is-in-pcsc-reader-name.html

[palu3492]

Sure thing. The output from printing the reader:

HID OMNIKEY 5427 CK (010100534E5634303101122020194630) 00 00

Again, the output from connection.getAttrib(SCARD_ATTR_VENDOR_IFD_SERIAL_NO) as decimal and ascii:

[48, 49, 48, 49, 48, 48, 53, 51, 52, 69, 53, 54, 51, 52, 51, 48, 51, 49, 48, 49, 49, 50, 50, 48, 50, 48, 49, 57, 52, 54, 51]
010100534E563430310112202019463

The pcscd log is attached. log.txt

[LudovicRousseau]

Unfortunately the log file does not contain anything useful for the debug :-( I can't reproduce the problem on my side. Also I have a different behavior:

Broadcom Corp 5880 [Contacted SmartCard] (0123456789ABCD) 00 00
[48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 65, 66, 67, 68, 0]
0123456789ABCD

The serial number is NOT truncated. And I also get the final NUL byte in the Attribute buffer.

I fixed a problem with SCARD_ATTR_VENDOR_IFD_SERIAL_NO in the CCID driver version 1.4.24. https://ludovicrousseau.blogspot.com/2016/05/new-version-of-libccid-1424.html Ubuntu 16.04 provides libccid version 1.4.22-1. Please upgrade this driver and try again.

[palu3492]

Interesting... I already have 1.4.22-1. That doesn't seem to be the problem. I tweaked your C code from https://ludovicrousseau.blogspot.com/2010/04/pcsc-sample-in-c.html and I was able to use SCardGetAttrib to return the correct serial number. Not sure if that means anything... Here's that truncated code:

LPBYTE pbAttr = NULL;
DWORD cByte = SCARD_AUTOALLOCATE;
DWORD w;
LONG lReturn;
lReturn = SCardGetAttrib(hCard,
                         65795,
                         (LPBYTE)&pbAttr,
                         &cByte);

for (w = 0; w < cByte; w++)
    printf("%c", *(pbAttr+w));

Copied from the example at https://docs.microsoft.com/en-us/windows/win32/api/winscard/nf-winscard-scardgetattrib

[LudovicRousseau]

1.4.22-1 is the problem. Upgrade to 1.4.24 or later.

[palu3492]

Ah, yes, I read your message incorrectly 🤦‍♂️ That fixed it. Thank you very much.