PC/SC v2 part 10 standard "
Part 10 IFDs with Secure PIN Entry Capabilities" offers a way to get some information from a smart card driver.
I already blogged about this service in
Using the
SCardControl(FEATURE_GET_TLV_PROPERTIES, ...) require some code to parse the result TLV buffer.
Library API
The idea of libPCSCv2part10 is to allow application programmers to use a function as simple as give_me_the_value_of_tag_x().
The library provides two functions:
PCSCv2Part10_find_TLV_property_by_tag_from_buffer() "low" levelPCSCv2Part10_find_TLV_property_by_tag_from_hcard() "high" level
The difference between the two functions is that
PCSCv2Part10_find_TLV_property_by_tag_from_hcard() uses a
SCARDHANDLE hCard and
PCSCv2Part10_find_TLV_property_by_tag_from_buffer() uses a buffer already retrieved using
SCardControl(FEATURE_GET_TLV_PROPERTIES, ...)
The API is documented at
libPCSCv2part10.
The project is hosted in the
contrib/libPCSCv2part10/ directory of the
pcsc-lite project.
Sample code
/*
sample.c: example of use of libPCSCv2part10 helper functions
Copyright (C) 2012 Ludovic Rousseau
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
* $Id: sample.c 6416 2012-08-08 09:49:00Z rousseau $
*/
#include <stdio.h>
#ifdef __APPLE__
#include <PCSC/winscard.h>
#include <PCSC/wintypes.h>
#else
#include <winscard.h>
#endif
#include <reader.h>
#include "PCSCv2part10.h"
/* PCSC error */
#define PCSC_ERROR_EXIT(rv) \
if (rv != SCARD_S_SUCCESS) \
{ \
printf("Failed at line %d with %s (0x%lX)\n", __LINE__, pcsc_stringify_error(rv), rv); \
goto end; \
}
int main(void)
{
LONG rv;
SCARDCONTEXT hContext;
SCARDHANDLE hCard;
int value, ret = -1;
DWORD dwReaders, dwPref;
char *mszReaders;
rv = SCardEstablishContext(SCARD_SCOPE_SYSTEM, NULL, NULL, &hContext);
PCSC_ERROR_EXIT(rv)
dwReaders = SCARD_AUTOALLOCATE;
rv = SCardListReaders(hContext, NULL, (LPSTR)&mszReaders, &dwReaders);
PCSC_ERROR_EXIT(rv)
/* use first reader */
printf("Using reaer: %s\n", mszReaders);
rv = SCardConnect(hContext, mszReaders,
SCARD_SHARE_SHARED, SCARD_PROTOCOL_T0 | SCARD_PROTOCOL_T1,
&hCard, &dwPref);
/* the interesting part is here */
ret = PCSCv2Part10_find_TLV_property_by_tag_from_hcard(hCard,
PCSCv2_PART10_PROPERTY_wIdVendor, &value);
printf("ret: %d\n", ret);
printf("value for PCSCv2_PART10_PROPERTY_wIdVendor: 0x%04X\n", value),
rv = SCardDisconnect(hCard, SCARD_LEAVE_CARD);
PCSC_ERROR_EXIT(rv)
rv = SCardFreeMemory(hContext, mszReaders);
PCSC_ERROR_EXIT(rv)
rv = SCardReleaseContext(hContext);
PCSC_ERROR_EXIT(rv)
end:
return ret;
}
How to use it
The code is very short. I don't think it is a good idea to make a library with just two functions. My idea is that a project FooBar using the function will just integrate the two files (
PCSCv2part10.c and
PCSCv2part10.h) into the project FooBar.
License
The license is GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
Conclusion
Feel free to use the code, make comments or improvements.
