pcsc.c

/*
 +----------------------------------------------------------------------+
 | Copyright (c) The PHP Group                                          |
 +----------------------------------------------------------------------+
 | This source file is subject to version 3.01 of the PHP license,      |
 | that is bundled with this package in the file LICENSE, and is        |
 | available through the world-wide-web at the following url:           |
 | http://www.php.net/license/3_01.txt                                  |
 | If you did not receive a copy of the PHP license and are unable to   |
 | obtain it through the world-wide-web, please send a note to          |
 | license@php.net so we can mail you a copy immediately.               |
 +----------------------------------------------------------------------+
 | Author: Johannes Findeisen <you@hanez.org> - 2010                    |
 +----------------------------------------------------------------------+
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "php.h"
#include "php_ini.h"
#include "ext/standard/info.h"
#include "php_pcsc.h"

ZEND_DECLARE_MODULE_GLOBALS(pcsc);

/* Compatibility shims */
#ifndef ZEND_FETCH_RESOURCE
#define ZEND_FETCH_RESOURCE(res, stmt_type, stmt, stmt_id, resource_type_name, le_stmt) \
  res = (stmt_type)zend_fetch_resource(Z_RES_P(*stmt),resource_type_name,le_stmt);
#endif

#ifndef FALSE
#define FALSE 0
#define TRUE 1
#endif

#if PHP_VERSION_ID < 80000
#include "pcsc_legacy_arginfo.h"
#else
#include "pcsc_arginfo.h"
#endif

/* {{{ pcsc_module_entry
 */
zend_module_entry pcsc_module_entry = {
#if ZEND_MODULE_API_NO >= 20010901
  STANDARD_MODULE_HEADER,
#endif
  "PC/SC",
  ext_functions,
  PHP_MINIT(pcsc),
  PHP_MSHUTDOWN(pcsc),
  NULL,
  NULL,
  PHP_MINFO(pcsc),
#if ZEND_MODULE_API_NO >= 20010901
  PHP_PCSC_VERSION,
#endif
  STANDARD_MODULE_PROPERTIES
};
/* }}} */

#ifdef COMPILE_DL_PCSC
ZEND_GET_MODULE(pcsc)
#endif

#define REGISTER_PCSC_CONSTANT(__c) REGISTER_LONG_CONSTANT(#__c, __c, CONST_CS | CONST_PERSISTENT)

/* resource container: context */
static int le_pcsc_ctx_res;
static void php_pcsc_ctx_res_dtor(zend_resource *rsrc) {
  SCARDCONTEXT context;
  LONG rc=0;

  context=(SCARDCONTEXT)rsrc->ptr;
  rc = SCardIsValidContext(context);
  if (rc != SCARD_S_SUCCESS) {
    php_error_docref(NULL, E_WARNING, "PC/SC context dtor: SCardIsValidContext returned %s (0x%lx)", php_pcsc_error_to_string(rc), rc);
    return;
  }

  rc = SCardReleaseContext(context);
  if (rc != SCARD_S_SUCCESS) {
    php_error_docref(NULL, E_WARNING, "PC/SC context dtor: SCardReleaseContext returned %s (0x%lx)", php_pcsc_error_to_string(rc), rc);
    return;
  }
  return;
}

/* resource container: connection */
static int le_pcsc_conn_res;
static void php_pcsc_conn_res_dtor(zend_resource *rsrc) {
  SCARDHANDLE hCard;
  LONG rc;

  //TODO: actually use this
  return;
  php_printf("conn dtor\n");
  hCard=(SCARDHANDLE)rsrc->ptr;

  rc = SCardDisconnect(hCard, SCARD_LEAVE_CARD);
  if (rc != SCARD_S_SUCCESS) {
    php_error_docref(NULL, E_WARNING, "PC/SC connection dtor: SCardDisconnect returned %s (0x%lx)", php_pcsc_error_to_string(rc), rc);
  }
}

/* TLS */
static void php_pcsc_globals_ctor(zend_pcsc_globals* pcsc_globals) {
  pcsc_globals->last_errno=SCARD_S_SUCCESS;
}

/* {{{ PHP_MINIT_FUNCTION
 */
PHP_MINIT_FUNCTION(pcsc)
{
  /* Return Codes */
#ifdef SCARD_E_BAD_SEEK
  REGISTER_PCSC_CONSTANT(SCARD_E_BAD_SEEK);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_CANCELLED);
  REGISTER_PCSC_CONSTANT(SCARD_E_CANT_DISPOSE);
  REGISTER_PCSC_CONSTANT(SCARD_E_CARD_UNSUPPORTED);
#ifdef SCARD_E_CERTIFICATE_UNAVAILABLE
  REGISTER_PCSC_CONSTANT(SCARD_E_CERTIFICATE_UNAVAILABLE);
#endif
#ifdef SCARD_E_COMM_DATA_LOST
  REGISTER_PCSC_CONSTANT(SCARD_E_COMM_DATA_LOST);
#endif
#ifdef SCARD_E_DIR_NOT_FOUND
  REGISTER_PCSC_CONSTANT(SCARD_E_DIR_NOT_FOUND);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_DUPLICATE_READER);
#ifdef SCARD_E_FILE_NOT_FOUND
  REGISTER_PCSC_CONSTANT(SCARD_E_FILE_NOT_FOUND);
#endif
#ifdef SCARD_E_ICC_CREATEORDER
  REGISTER_PCSC_CONSTANT(SCARD_E_ICC_CREATEORDER);
#endif
#ifdef SCARD_E_ICC_INSTALLATION
  REGISTER_PCSC_CONSTANT(SCARD_E_ICC_INSTALLATION);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_INSUFFICIENT_BUFFER);
  REGISTER_PCSC_CONSTANT(SCARD_E_INVALID_ATR);
#ifdef SCARD_E_INVALID_CHV
  REGISTER_PCSC_CONSTANT(SCARD_E_INVALID_CHV);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_INVALID_HANDLE);
  REGISTER_PCSC_CONSTANT(SCARD_E_INVALID_PARAMETER);
  REGISTER_PCSC_CONSTANT(SCARD_E_INVALID_TARGET);
  REGISTER_PCSC_CONSTANT(SCARD_E_INVALID_VALUE);
#ifdef SCARD_E_NO_ACCESS
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_ACCESS);
#endif
#ifdef SCARD_E_NO_DIR
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_DIR);
#endif
#ifdef SCARD_E_NO_FILE
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_FILE);
#endif
#ifdef SCARD_E_NO_KEY_CONTAINER
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_KEY_CONTAINER);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_MEMORY);
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_READERS_AVAILABLE);
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_SERVICE);
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_SMARTCARD);
#ifdef SCARD_E_NO_SUCH_CERTIFICATE
  REGISTER_PCSC_CONSTANT(SCARD_E_NO_SUCH_CERTIFICATE);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_NOT_READY);
  REGISTER_PCSC_CONSTANT(SCARD_E_NOT_TRANSACTED);
  REGISTER_PCSC_CONSTANT(SCARD_E_PCI_TOO_SMALL);
  REGISTER_PCSC_CONSTANT(SCARD_E_PROTO_MISMATCH);
  REGISTER_PCSC_CONSTANT(SCARD_E_READER_UNAVAILABLE);
  REGISTER_PCSC_CONSTANT(SCARD_E_READER_UNSUPPORTED);
#ifdef SCARD_E_SERVER_TOO_BUSY
  REGISTER_PCSC_CONSTANT(SCARD_E_SERVER_TOO_BUSY);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_SERVICE_STOPPED);
  REGISTER_PCSC_CONSTANT(SCARD_E_SHARING_VIOLATION);
  REGISTER_PCSC_CONSTANT(SCARD_E_SYSTEM_CANCELLED);
  REGISTER_PCSC_CONSTANT(SCARD_E_TIMEOUT);
#ifdef SCARD_E_UNEXPECTED
  REGISTER_PCSC_CONSTANT(SCARD_E_UNEXPECTED);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_UNKNOWN_CARD);
  REGISTER_PCSC_CONSTANT(SCARD_E_UNKNOWN_READER);
#ifdef SCARD_E_UNKNOWN_RES_MNG
  REGISTER_PCSC_CONSTANT(SCARD_E_UNKNOWN_RES_MNG);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_E_UNSUPPORTED_FEATURE);
#ifdef SCARD_E_WRITE_TOO_MANY
  REGISTER_PCSC_CONSTANT(SCARD_E_WRITE_TOO_MANY);
#endif

  REGISTER_PCSC_CONSTANT(SCARD_F_COMM_ERROR);
  REGISTER_PCSC_CONSTANT(SCARD_F_INTERNAL_ERROR);
  REGISTER_PCSC_CONSTANT(SCARD_F_UNKNOWN_ERROR);
  REGISTER_PCSC_CONSTANT(SCARD_F_WAITED_TOO_LONG);

#ifdef SCARD_P_SHUTDOWN
  REGISTER_PCSC_CONSTANT(SCARD_P_SHUTDOWN);
#endif

  REGISTER_PCSC_CONSTANT(SCARD_S_SUCCESS);

#ifdef SCARD_W_CANCELLED_BY_USER
  REGISTER_PCSC_CONSTANT(SCARD_W_CANCELLED_BY_USER);
#endif
#ifdef SCARD_W_CARD_NOT_AUTHENTICATED
  REGISTER_PCSC_CONSTANT(SCARD_W_CARD_NOT_AUTHENTICATED);
#endif
#ifdef SCARD_W_CHV_BLOCKED
  REGISTER_PCSC_CONSTANT(SCARD_W_CHV_BLOCKED);
#endif
#ifdef SCARD_W_EOF
  REGISTER_PCSC_CONSTANT(SCARD_W_EOF);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_W_REMOVED_CARD);
  REGISTER_PCSC_CONSTANT(SCARD_W_RESET_CARD);
#ifdef SCARD_W_SECURITY_VIOLATION
  REGISTER_PCSC_CONSTANT(SCARD_W_SECURITY_VIOLATION);
#endif
  REGISTER_PCSC_CONSTANT(SCARD_W_UNPOWERED_CARD);
  REGISTER_PCSC_CONSTANT(SCARD_W_UNRESPONSIVE_CARD);
  REGISTER_PCSC_CONSTANT(SCARD_W_UNSUPPORTED_CARD);
#ifdef SCARD_W_WRONG_CHV
  REGISTER_PCSC_CONSTANT(SCARD_W_WRONG_CHV);
#endif

  /* Protocols */
  REGISTER_PCSC_CONSTANT(SCARD_PROTOCOL_RAW);
  REGISTER_PCSC_CONSTANT(SCARD_PROTOCOL_T0);
  REGISTER_PCSC_CONSTANT(SCARD_PROTOCOL_T1);

  /* Disconnect Modes */
  REGISTER_PCSC_CONSTANT(SCARD_EJECT_CARD);
  REGISTER_PCSC_CONSTANT(SCARD_LEAVE_CARD);
  REGISTER_PCSC_CONSTANT(SCARD_RESET_CARD);
  REGISTER_PCSC_CONSTANT(SCARD_UNPOWER_CARD);

  /* Status codes */
  REGISTER_PCSC_CONSTANT(SCARD_ABSENT);
  REGISTER_PCSC_CONSTANT(SCARD_NEGOTIABLE);
  REGISTER_PCSC_CONSTANT(SCARD_POWERED);
  REGISTER_PCSC_CONSTANT(SCARD_PRESENT);
  REGISTER_PCSC_CONSTANT(SCARD_SPECIFIC);
  REGISTER_PCSC_CONSTANT(SCARD_SWALLOWED);

  /* resource containers */
  le_pcsc_ctx_res=zend_register_list_destructors_ex(php_pcsc_ctx_res_dtor, NULL, PHP_PCSC_CTX_RES_NAME,module_number);
  le_pcsc_conn_res=zend_register_list_destructors_ex(php_pcsc_conn_res_dtor, NULL, PHP_PCSC_CONN_RES_NAME,module_number);

  /* TLS */
  #ifdef ZTS
  ts_allocate_id(&pcsc_globals_id,sizeof(zend_pcsc_globals),(ts_allocate_ctor)php_pcsc_globals_ctor, NULL);
  #else
  php_pcsc_globals_ctor(&pcsc_globals);
  #endif

  return SUCCESS;
}
/* }}} */

/* {{{ PHP_MSHUTDOWN_FUNCTION
 */
PHP_MSHUTDOWN_FUNCTION(pcsc)
{
  return SUCCESS;
}
/* }}} */

/* {{{ PHP_MINFO_FUNCTION
 */
PHP_MINFO_FUNCTION(pcsc)
{
  php_info_print_table_start();
  php_info_print_table_header(2, "PC/SC support", "enabled");
  php_info_print_table_end();
}
/* }}} */

/* map error codes to string */
static char* php_pcsc_error_to_string(DWORD dwRC) {
  switch(dwRC) {
#ifdef SCARD_E_BAD_SEEK
    case SCARD_E_BAD_SEEK: return "SCARD_E_BAD_SEEK";
#endif
    case SCARD_E_CANCELLED: return "SCARD_E_CANCELLED";
    case SCARD_E_CANT_DISPOSE: return "SCARD_E_CANT_DISPOSE";
    case SCARD_E_CARD_UNSUPPORTED: return "SCARD_E_CARD_UNSUPPORTED";
#ifdef SCARD_E_CERTIFICATE_UNAVAILABLE
    case SCARD_E_CERTIFICATE_UNAVAILABLE: return "SCARD_E_CERTIFICATE_UNAVAILABLE";
#endif
#ifdef SCARD_E_COMM_DATA_LOST
    case SCARD_E_COMM_DATA_LOST: return "SCARD_E_COMM_DATA_LOST";
#endif
#ifdef SCARD_E_DIR_NOT_FOUND
    case SCARD_E_DIR_NOT_FOUND: return "SCARD_E_DIR_NOT_FOUND";
#endif
    case SCARD_E_DUPLICATE_READER: return "SCARD_E_DUPLICATE_READER";
#ifdef SCARD_E_FILE_NOT_FOUND
    case SCARD_E_FILE_NOT_FOUND: return "SCARD_E_FILE_NOT_FOUND";
#endif
#ifdef SCARD_E_ICC_CREATEORDER
    case SCARD_E_ICC_CREATEORDER: return "SCARD_E_ICC_CREATEORDER";
#endif
#ifdef SCARD_E_ICC_INSTALLATION
    case SCARD_E_ICC_INSTALLATION: return "SCARD_E_ICC_INSTALLATION";
#endif
    case SCARD_E_INSUFFICIENT_BUFFER: return "SCARD_E_INSUFFICIENT_BUFFER";
    case SCARD_E_INVALID_ATR: return "SCARD_E_INVALID_ATR";
#ifdef SCARD_E_INVALID_CHV
    case SCARD_E_INVALID_CHV: return "SCARD_E_INVALID_CHV";
#endif
    case SCARD_E_INVALID_HANDLE: return "SCARD_E_INVALID_HANDLE";
    case SCARD_E_INVALID_PARAMETER: return "SCARD_E_INVALID_PARAMETER";
    case SCARD_E_INVALID_TARGET: return "SCARD_E_INVALID_TARGET";
    case SCARD_E_INVALID_VALUE: return "SCARD_E_INVALID_VALUE";
#ifdef SCARD_E_NO_ACCESS
    case SCARD_E_NO_ACCESS: return "SCARD_E_NO_ACCESS";
#endif
#ifdef SCARD_E_NO_DIR
    case SCARD_E_NO_DIR: return "SCARD_E_NO_DIR";
#endif
#ifdef SCARD_E_NO_FILE
    case SCARD_E_NO_FILE: return "SCARD_E_NO_FILE";
#endif
#ifdef SCARD_E_NO_KEY_CONTAINER
    case SCARD_E_NO_KEY_CONTAINER: return "SCARD_E_NO_KEY_CONTAINER";
#endif
    case SCARD_E_NO_MEMORY: return "SCARD_E_NO_MEMORY";
    case SCARD_E_NO_READERS_AVAILABLE: return "SCARD_E_NO_READERS_AVAILABLE";
    case SCARD_E_NO_SERVICE: return "SCARD_E_NO_SERVICE";
    case SCARD_E_NO_SMARTCARD: return "SCARD_E_NO_SMARTCARD";
#ifdef SCARD_E_NO_ACCESS
    case SCARD_E_NO_SUCH_CERTIFICATE: return "SCARD_E_NO_SUCH_CERTIFICATE";
#endif
    case SCARD_E_NOT_READY: return "SCARD_E_NOT_READY";
    case SCARD_E_NOT_TRANSACTED: return "SCARD_E_NOT_TRANSACTED";
    case SCARD_E_PCI_TOO_SMALL: return "SCARD_E_PCI_TOO_SMALL";
    case SCARD_E_PROTO_MISMATCH: return "SCARD_E_PROTO_MISMATCH";
    case SCARD_E_READER_UNAVAILABLE: return "SCARD_E_READER_UNAVAILABLE";
    case SCARD_E_READER_UNSUPPORTED: return "SCARD_E_READER_UNSUPPORTED";
#ifdef SCARD_E_SERVER_TOO_BUSY
    case SCARD_E_SERVER_TOO_BUSY: return "SCARD_E_SERVER_TOO_BUSY";
#endif
    case SCARD_E_SERVICE_STOPPED: return "SCARD_E_SERVICE_STOPPED";
    case SCARD_E_SHARING_VIOLATION: return "SCARD_E_SHARING_VIOLATION";
    case SCARD_E_SYSTEM_CANCELLED: return "SCARD_E_SYSTEM_CANCELLED";
    case SCARD_E_TIMEOUT: return "SCARD_E_TIMEOUT";
#ifdef SCARD_E_UNEXPECTED
    case SCARD_E_UNEXPECTED: return "SCARD_E_UNEXPECTED";
#endif
    case SCARD_E_UNKNOWN_CARD: return "SCARD_E_UNKNOWN_CARD";
    case SCARD_E_UNKNOWN_READER: return "SCARD_E_UNKNOWN_READER";
#ifdef SCARD_E_UNKNOWN_RES_MNG
    case SCARD_E_UNKNOWN_RES_MNG: return "SCARD_E_UNKNOWN_RES_MNG";
#endif
/* apparently E_UNEXPECTED and E_UNSUPPORTED are defined
   by a buggy header file on Linux, causing a "double used constant"
   error. Just leave this out on Linux, then.
*/
#ifdef PHP_WIN32
                case SCARD_E_UNSUPPORTED_FEATURE: return "SCARD_E_UNSUPPORTED_FEATURE";
#endif
#ifdef SCARD_E_WRITE_TOO_MANY
    case SCARD_E_WRITE_TOO_MANY: return "SCARD_E_WRITE_TOO_MANY";
#endif
    case SCARD_F_COMM_ERROR: return "SCARD_E_WRITE_TOO_MANY";
    case SCARD_F_INTERNAL_ERROR: return "SCARD_F_INTERNAL_ERROR";
    case SCARD_F_UNKNOWN_ERROR: return "SCARD_F_UNKNOWN_ERROR";
    case SCARD_F_WAITED_TOO_LONG: return "SCARD_F_WAITED_TOO_LONG";
#ifdef SCARD_P_SHUTDOWN
    case SCARD_P_SHUTDOWN: return "SCARD_P_SHUTDOWN";
#endif
    case SCARD_S_SUCCESS: return "SCARD_S_SUCCESS";
#ifdef SCARD_W_CANCELLED_BY_USER
    case SCARD_W_CANCELLED_BY_USER: return "SCARD_W_CANCELLED_BY_USER";
#endif
#ifdef SCARD_W_CACHE_ITEM_NOT_FOUND
    case SCARD_W_CACHE_ITEM_NOT_FOUND: return "SCARD_W_CACHE_ITEM_NOT_FOUND";
#endif
#ifdef SCARD_W_CACHE_ITEM_STALE
    case SCARD_W_CACHE_ITEM_STALE: return "SCARD_W_CACHE_ITEM_STALE";
#endif
#ifdef SCARD_W_CACHE_ITEM_TOO_BIG
    case SCARD_W_CACHE_ITEM_TOO_BIG: return "SCARD_W_CACHE_ITEM_TOO_BIG";
#endif
#ifdef SCARD_W_CARD_NOT_AUTHENTICATED
    case SCARD_W_CARD_NOT_AUTHENTICATED: return "SCARD_W_CARD_NOT_AUTHENTICATED";
#endif
#ifdef SCARD_W_CHV_BLOCKED
    case SCARD_W_CHV_BLOCKED: return "SCARD_W_CHV_BLOCKED";
#endif
#ifdef SCARD_W_EOF
    case SCARD_W_EOF: return "SCARD_W_EOF";
#endif
    case SCARD_W_REMOVED_CARD: return "SCARD_W_REMOVED_CARD";
    case SCARD_W_RESET_CARD: return "SCARD_W_RESET_CARD";
#ifdef SCARD_W_SECURITY_VIOLATION
    case SCARD_W_SECURITY_VIOLATION: return "SCARD_W_SECURITY_VIOLATION";
#endif
    case SCARD_W_UNPOWERED_CARD: return "SCARD_W_UNPOWERED_CARD";
    case SCARD_W_UNRESPONSIVE_CARD: return "SCARD_W_UNRESPONSIVE_CARD";
    case SCARD_W_UNSUPPORTED_CARD: return "SCARD_W_UNSUPPORTED_CARD";
#ifdef SCARD_W_WRONG_CHV
    case SCARD_W_WRONG_CHV: return "SCARD_W_WRONG_CHV";
#endif
    default: return "Unknown";
  }
}

static char *e_bytes_to_hex(BYTE *buffer, DWORD length)
{
  DWORD i;
  char tmp[3];
  char *str;

  str = emalloc(2 * length + 1);
  str[0] = '\0';

  for (i = 0; i < length; i++) {
    sprintf(tmp, "%02X", buffer[i]);
    strcat(str, tmp);
  }
  return str;
}

static BYTE hex_to_nibble(char chr)
{
  if ((chr >= '0') && (chr <= '9')) {
    return chr - '0';
  }
  if ((chr >= 'A') && (chr <= 'F')) {
    return chr - 'A' + 10;
  }
  if ((chr >= 'a') && (chr <= 'f')) {
    return chr - 'a' + 10;
  }
  return 0;
}

static BYTE hex_to_byte(char *str)
{
  return hex_to_nibble(str[0]) * 0x10 + hex_to_nibble(str[1]);
}

static BYTE *e_hex_to_bytes(char *str, DWORD *length)
{
  DWORD i, l;
  BYTE *buf;

  if (str == NULL) {
    return NULL;
  }

  l = strlen(str) / 2;
  if (length != NULL) {
    *length = l;
  }

  buf = emalloc(l);

  for (i = 0; i < l; i++) {
    buf[i] = hex_to_byte(&str[2 * i]);
  }
  return buf;
}

/* {{{ proto resource scard_establish_context()
   Return a a context to the PC/SC layer */
PHP_FUNCTION(scard_establish_context)
{
  SCARDCONTEXT scard_context = 0;
  LONG rc = 0;

  if (zend_parse_parameters_none() == FAILURE) {
    return;
  }

  rc = SCardEstablishContext(SCARD_SCOPE_SYSTEM, NULL, NULL, &scard_context);
  if (rc != SCARD_S_SUCCESS)
  {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }

  RETURN_RES(zend_register_resource((void*)scard_context,le_pcsc_ctx_res));
}
/* }}} */

/* {{{ proto boolean scard_is_valid_context(resource context)
   Checks if the PC/SC context is valid */
PHP_FUNCTION(scard_is_valid_context)
{
  LONG rc = 0;
  zval* ctx_res;
  SCARDCONTEXT context;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "r", &ctx_res) == FAILURE) {
    RETURN_NULL();
  }
  ZEND_FETCH_RESOURCE(context, SCARDCONTEXT, &ctx_res, -1, PHP_PCSC_CTX_RES_NAME, le_pcsc_ctx_res);

  rc = SCardIsValidContext(context);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }
  RETURN_TRUE;
}
/* }}} */

/* {{{ proto boolean scard_release_context(long context)
   Invalidate the PC/SC context */
PHP_FUNCTION(scard_release_context)
{
  zval* ctx_res;
  SCARDCONTEXT context;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "r", &ctx_res) == FAILURE) {
    RETURN_NULL();
  }
  ZEND_FETCH_RESOURCE(context, SCARDCONTEXT, &ctx_res, -1, PHP_PCSC_CTX_RES_NAME, le_pcsc_ctx_res);
  (void)context;

  zend_hash_index_del(&EG(regular_list), Z_RES_HANDLE_P(ctx_res));
  RETURN_TRUE;
}
/* }}} */

/* {{{ proto array scard_list_readers(resource context)
   Return an array of available PC/SC readers */
PHP_FUNCTION(scard_list_readers)
{
  char *strReaders = NULL;
  char *ptrReader;
  DWORD dwLen = SCARD_AUTOALLOCATE;
  LONG rc = 0;
  zval* ctx_res;
  SCARDCONTEXT context;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "r", &ctx_res) == FAILURE) {
    RETURN_NULL();
  }
  ZEND_FETCH_RESOURCE(context, SCARDCONTEXT, &ctx_res, -1, PHP_PCSC_CTX_RES_NAME, le_pcsc_ctx_res);

  rc = SCardListReaders(context, NULL, (char *) &strReaders, &dwLen);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }

  if (strReaders == NULL) {
    RETURN_FALSE;
  }

  array_init(return_value);

  ptrReader = strReaders;
  do {
    add_next_index_string(return_value, ptrReader);
    ptrReader+= strlen(ptrReader);
    ptrReader++;
  } while (*ptrReader != '\0');

  SCardFreeMemory(context, strReaders);
}
/* }}} */

/* {{{ proto resource scard_connect(resource context, string reader_name, [long preferred_protocol], [long &current_protocol])
   Return a handle to the card */
PHP_FUNCTION(scard_connect)
{
  DWORD dwPreferredProtocol = SCARD_PROTOCOL_RAW | SCARD_PROTOCOL_T0 | SCARD_PROTOCOL_T1;
  DWORD dwCurrentProtocol;
  SCARDHANDLE hCard = 0;
  LONG rc = 0;
  zval* ctx_res;
  zval* current_protocol;
  SCARDCONTEXT context;
  char *strReaderName;
  size_t strReaderNameLen;
  zend_long preferred_protocol;

  current_protocol = NULL;
  ctx_res = NULL;
  if (zend_parse_parameters(ZEND_NUM_ARGS(), "rs|lz", &ctx_res, &strReaderName, &strReaderNameLen, &preferred_protocol, &current_protocol) == FAILURE) {
    RETURN_NULL();
  }
  if (current_protocol != NULL) {
    ZVAL_LONG(current_protocol, 0);
  }
  /* if the third arg (preferred protocol override) was passed */
  if (ZEND_NUM_ARGS() > 2) {
    dwPreferredProtocol = (DWORD)preferred_protocol;
  }
  ZEND_FETCH_RESOURCE(context, SCARDCONTEXT, &ctx_res, -1, PHP_PCSC_CTX_RES_NAME, le_pcsc_ctx_res);

  rc = SCardConnect(context, strReaderName, SCARD_SHARE_SHARED, dwPreferredProtocol, &hCard, &dwCurrentProtocol);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }
  if (current_protocol != NULL) {
    ZVAL_LONG(current_protocol, dwCurrentProtocol);
  }

  RETURN_RES(zend_register_resource((void*)hCard, le_pcsc_conn_res));
}
/* }}} */

/* {{{ proto boolean scard_disconnect(resource card_handle, [long disposition = SCARD_EJECT_CARD])
   Close a card connection obtained with scard_connect */
PHP_FUNCTION(scard_disconnect)
{
  zend_long dwDisposition = SCARD_EJECT_CARD;
  LONG rc;
  zval* conn_res;
  SCARDHANDLE hCard;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "r|l", &conn_res, &dwDisposition) == FAILURE) {
    return;
  }
  ZEND_FETCH_RESOURCE(hCard, SCARDHANDLE, &conn_res, -1, PHP_PCSC_CONN_RES_NAME, le_pcsc_conn_res);

  rc = SCardDisconnect(hCard, (DWORD)dwDisposition);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }
  RETURN_TRUE;
}
/* }}} */

/* {{{ proto boolean scard_begin_transaction(resource card_handle)
   Begin transaction on a card connection obtained with scard_connect */
PHP_FUNCTION(scard_begin_transaction)
{
  LONG rc;
  zval* conn_res;
  SCARDHANDLE hCard;

  ZEND_FETCH_RESOURCE(hCard, SCARDHANDLE, &conn_res, -1, PHP_PCSC_CONN_RES_NAME, le_pcsc_conn_res);

  rc = SCardBeginTransaction(hCard);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }
  RETURN_TRUE;
}
/* }}} */

/* {{{ proto boolean scard_end_transaction(resource card_handle, [long disposition = SCARD_LEAVE_CARD])
   End a previously begun transaction invoked by scard_begin_transaction on a card connection obtained with scard_connect; If no transaction began, do nothing. */
PHP_FUNCTION(scard_end_transaction)
{
  zend_long dwDisposition = SCARD_LEAVE_CARD;
  LONG rc;
  zval* conn_res;
  SCARDHANDLE hCard;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "r|l", &conn_res, &dwDisposition) == FAILURE) {
    return;
  }
  ZEND_FETCH_RESOURCE(hCard, SCARDHANDLE, &conn_res, -1, PHP_PCSC_CONN_RES_NAME, le_pcsc_conn_res);

  rc = SCardEndTransaction(hCard, (DWORD)dwDisposition);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }
  RETURN_TRUE;
}
/* }}} */

/* {{{ proto string scard_transmit(resource card_handle, string send_command)
   Transmit (and receive) data to (and from) the card */
PHP_FUNCTION(scard_transmit)
{
  SCARDHANDLE hCard;
  zval* conn_res;
  DWORD dwProtocol;
  DWORD dwState;
  const SCARD_IO_REQUEST *sendPci = NULL;
  SCARD_IO_REQUEST *recvPci = NULL;
  BYTE *sendBuffer;
  BYTE *recvBuffer;
  DWORD sendLen = 0, recvLen;
  LONG rc;
  char *apdu;
  size_t apduLen;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "rs", &conn_res, &apdu, &apduLen) == FAILURE) {
    return;
  }
  ZEND_FETCH_RESOURCE(hCard, SCARDHANDLE, &conn_res, -1, PHP_PCSC_CONN_RES_NAME, le_pcsc_conn_res);

  /* Are we in T=0 or T=1 ? Is the card powered? */
  rc = SCardStatus(hCard, NULL, NULL, &dwState, &dwProtocol, NULL, NULL);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }

  if (!(dwState & SCARD_POWERED)) {
  PCSC_G(last_errno) = SCARD_W_UNPOWERED_CARD;
    RETURN_FALSE;
  }

  switch (dwProtocol) {
    case SCARD_PROTOCOL_RAW : sendPci = SCARD_PCI_RAW; break;
    case SCARD_PROTOCOL_T0  : sendPci = SCARD_PCI_T0;  break;
    case SCARD_PROTOCOL_T1  : sendPci = SCARD_PCI_T1;  break;
  }

  /* Get buffer to send */
  sendBuffer = e_hex_to_bytes(apdu, &sendLen);

  /* Guess the size of the buffer to recv */
  recvLen    = 2 + 256;
  recvBuffer = emalloc(recvLen);

  /* Perform the exchange */
  recvPci = emalloc(1024);
  recvPci->dwProtocol  = dwProtocol;
  recvPci->cbPciLength = 1024;

  rc = SCardTransmit(hCard, sendPci, sendBuffer, sendLen, recvPci, recvBuffer, &recvLen);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    efree(recvPci);
    efree(recvBuffer);
    efree(sendBuffer);
    RETURN_FALSE;
  }
  efree(recvPci);

  /* Return the response */
  RETVAL_STRING(e_bytes_to_hex(recvBuffer, recvLen));

  /* Free local data */
  efree(recvBuffer);
  efree(sendBuffer);
}
/* }}} */

/* {{{ proto array scard_status([resource card_handle])
   Retrieve reader's or card's status */
PHP_FUNCTION(scard_status)
{
  zval* conn_res;
  SCARDHANDLE hCard = 0;
  DWORD dwProtocol, dwState;
  BYTE atrBuffer[32];
  DWORD atrLen;
  LONG rc;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "r", &conn_res) == FAILURE) {
    return;
  }
  ZEND_FETCH_RESOURCE(hCard, SCARDHANDLE, &conn_res, -1, PHP_PCSC_CONN_RES_NAME, le_pcsc_conn_res);

  atrLen = sizeof(atrBuffer);
  rc = SCardStatus(hCard, NULL, NULL, &dwState, &dwProtocol, atrBuffer, &atrLen);
  if (rc != SCARD_S_SUCCESS) {
  PCSC_G(last_errno) = rc;
    RETURN_FALSE;
  }

  array_init(return_value);
  add_assoc_long(return_value, "state",    dwState);
  if (dwState & SCARD_ABSENT)
    add_assoc_long(return_value, "SCARD_ABSENT", 1);

  if (dwState & SCARD_PRESENT)
    add_assoc_long(return_value, "SCARD_PRESENT", 1);

  if (dwState & SCARD_SWALLOWED)
    add_assoc_long(return_value, "SCARD_SWALLOWED", 1);

  if (dwState & SCARD_POWERED)
    add_assoc_long(return_value, "SCARD_POWERED", 1);

  if (dwState & SCARD_NEGOTIABLE)
    add_assoc_long(return_value, "SCARD_NEGOTIABLE", 1);

  if (dwState & SCARD_SPECIFIC)
    add_assoc_long(return_value, "SCARD_SPECIFIC", 1);

  switch (dwProtocol) {
    case SCARD_PROTOCOL_RAW : add_assoc_long(return_value, "SCARD_PROTOCOL_RAW", 1);
                              add_assoc_string(return_value, "PROTOCOL", "RAW");
                              break;
    case SCARD_PROTOCOL_T0  : add_assoc_long(return_value, "SCARD_PROTOCOL_T0", 1);
                              add_assoc_string(return_value, "PROTOCOL", "T=0");
                              break;
    case SCARD_PROTOCOL_T1  : add_assoc_long(return_value, "SCARD_PROTOCOL_T1", 1);
                              add_assoc_string(return_value, "PROTOCOL", "T=1");
                              break;
    default                 : add_assoc_long(return_value, "PROTOCOL", dwProtocol);
  }

  if (atrLen) {
    char *atrString;
    atrString = e_bytes_to_hex(atrBuffer, atrLen);
    add_assoc_string(return_value, "ATR", atrString);
    efree(atrString);
  }
}
/* }}} */

/* {{{ proto long scard_last_errno()
   Retrieve last error code */
PHP_FUNCTION(scard_last_errno)
{
    if (zend_parse_parameters_none() == FAILURE) {
      return;
    }
  RETURN_LONG(PCSC_G(last_errno));
}
/* }}} */

/* {{{ proto long scard_errstr(long errno)
   Retrieve string name of error code */
PHP_FUNCTION(scard_errstr)
{
  zend_long in_errno=0;
  if (zend_parse_parameters(ZEND_NUM_ARGS(), "l", &in_errno) == FAILURE) {
    RETURN_NULL();
  }
  RETURN_STRING(php_pcsc_error_to_string((DWORD)in_errno));
}
/* }}} */