gnupg/scd/apdu.c

/* apdu.c - ISO 7816 APDU functions and low level I/O
 *	Copyright (C) 2003, 2004 Free Software Foundation, Inc.
 *
 * This file is part of GnuPG.
 *
 * GnuPG is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * GnuPG 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */

#include <config.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#ifdef USE_GNU_PTH
# include <pth.h>
# include <unistd.h>
# include <fcntl.h>
#endif
#ifdef HAVE_OPENSC
# include <opensc/opensc.h>
#endif

#if defined(GNUPG_SCD_MAIN_HEADER)
#include GNUPG_SCD_MAIN_HEADER
#elif GNUPG_MAJOR_VERSION == 1
/* This is used with GnuPG version < 1.9.  The code has been source
   copied from the current GnuPG >= 1.9  and is maintained over
   there. */
#include "options.h"
#include "errors.h"
#include "memory.h"
#include "util.h"
#include "i18n.h"
#include "cardglue.h"
#else /* GNUPG_MAJOR_VERSION != 1 */
#include "scdaemon.h"
#endif /* GNUPG_MAJOR_VERSION != 1 */

#include "apdu.h"
#include "dynload.h"
#include "ccid-driver.h"

#ifdef USE_GNU_PTH
#define NEED_PCSC_WRAPPER 1
#endif


#define MAX_READER 4 /* Number of readers we support concurrently. */
#define CARD_CONNECT_TIMEOUT 1 /* Number of seconds to wait for
                                  insertion of the card (1 = don't wait). */


#ifdef _WIN32
#define DLSTDCALL __stdcall
#else
#define DLSTDCALL
#endif

#ifdef _POSIX_OPEN_MAX
#define MAX_OPEN_FDS _POSIX_OPEN_MAX
#else
#define MAX_OPEN_FDS 20
#endif


/* A structure to collect information pertaining to one reader
   slot. */
struct reader_table_s {
  int used;            /* True if slot is used. */
  unsigned short port; /* Port number:  0 = unused, 1 - dev/tty */
  int is_ccid;         /* Uses the internal CCID driver. */
  struct {
    ccid_driver_t handle;
  } ccid;
  int is_ctapi;        /* This is a ctAPI driver. */
  struct {
    unsigned long context;
    unsigned long card;
    unsigned long protocol;
#ifdef NEED_PCSC_WRAPPER
    int req_fd;
    int rsp_fd;
    pid_t pid;
#endif /*NEED_PCSC_WRAPPER*/
  } pcsc;
#ifdef HAVE_OPENSC
  int is_osc;          /* We are using the OpenSC driver layer. */
  struct {
    struct sc_context *ctx;
    struct sc_card *scard;
  } osc;
#endif /*HAVE_OPENSC*/
  int status;
  unsigned char atr[33];
  size_t atrlen;
  unsigned int change_counter;
#ifdef USE_GNU_PTH
  int lock_initialized;
  pth_mutex_t lock;
#endif
};
typedef struct reader_table_s *reader_table_t;

/* A global table to keep track of active readers. */
static struct reader_table_s reader_table[MAX_READER];


/* ct API function pointer. */
static char (* DLSTDCALL CT_init) (unsigned short ctn, unsigned short Pn);
static char (* DLSTDCALL CT_data) (unsigned short ctn, unsigned char *dad,
                                   unsigned char *sad, unsigned short lc,
                                   unsigned char *cmd, unsigned short *lr,
                                   unsigned char *rsp);
static char (* DLSTDCALL CT_close) (unsigned short ctn);

/* PC/SC constants and function pointer. */
#define PCSC_SCOPE_USER      0 
#define PCSC_SCOPE_TERMINAL  1 
#define PCSC_SCOPE_SYSTEM    2 
#define PCSC_SCOPE_GLOBAL    3 

#define PCSC_PROTOCOL_T0     1 
#define PCSC_PROTOCOL_T1     2 
#define PCSC_PROTOCOL_RAW    4 

#define PCSC_SHARE_EXCLUSIVE 1
#define PCSC_SHARE_SHARED    2
#define PCSC_SHARE_DIRECT    3

#define PCSC_LEAVE_CARD      0
#define PCSC_RESET_CARD      1
#define PCSC_UNPOWER_CARD    2
#define PCSC_EJECT_CARD      3

struct pcsc_io_request_s {
  unsigned long protocol; 
  unsigned long pci_len;
};

typedef struct pcsc_io_request_s *pcsc_io_request_t;

long (* DLSTDCALL pcsc_establish_context) (unsigned long scope,
                                           const void *reserved1,
                                           const void *reserved2,
                                           unsigned long *r_context);
long (* DLSTDCALL pcsc_release_context) (unsigned long context);
long (* DLSTDCALL pcsc_list_readers) (unsigned long context,
                                      const char *groups,
                                      char *readers, unsigned long*readerslen);
long (* DLSTDCALL pcsc_connect) (unsigned long context,
                                 const char *reader,
                                 unsigned long share_mode,
                                 unsigned long preferred_protocols,
                                 unsigned long *r_card,
                                 unsigned long *r_active_protocol);
long (* DLSTDCALL pcsc_disconnect) (unsigned long card,
                                    unsigned long disposition);
long (* DLSTDCALL pcsc_status) (unsigned long card,
                                char *reader, unsigned long *readerlen,
                                unsigned long *r_state,
                                unsigned long *r_protocol,
                                unsigned char *atr, unsigned long *atrlen);
long (* DLSTDCALL pcsc_begin_transaction) (unsigned long card);
long (* DLSTDCALL pcsc_end_transaction) (unsigned long card);
long (* DLSTDCALL pcsc_transmit) (unsigned long card,
                                  const pcsc_io_request_t send_pci,
                                  const unsigned char *send_buffer,
                                  unsigned long send_len,
                                  pcsc_io_request_t recv_pci,
                                  unsigned char *recv_buffer,
                                  unsigned long *recv_len);
long (* DLSTDCALL pcsc_set_timeout) (unsigned long context,
                                     unsigned long timeout);





/* 
      Helper
 */
 

/* Find an unused reader slot for PORTSTR and put it into the reader
   table.  Return -1 on error or the index into the reader table. */
static int 
new_reader_slot (void)    
{
  int i, reader = -1;

  for (i=0; i < MAX_READER; i++)
    {
      if (!reader_table[i].used && reader == -1)
        reader = i;
    }
  if (reader == -1)
    {
      log_error ("new_reader_slot: out of slots\n");
      return -1;
    }
#ifdef USE_GNU_PTH
  if (!reader_table[reader].lock_initialized)
    {
      if (!pth_mutex_init (&reader_table[reader].lock))
        {
          log_error ("error initializing mutex: %s\n", strerror (errno));
          return -1;
        }
      reader_table[reader].lock_initialized = 1;
    }
#endif /*USE_GNU_PTH*/
  reader_table[reader].used = 1;
  reader_table[reader].is_ccid = 0;
  reader_table[reader].is_ctapi = 0;
#ifdef HAVE_OPENSC
  reader_table[reader].is_osc = 0;
#endif
#ifdef NEED_PCSC_WRAPPER
  reader_table[reader].pcsc.req_fd = -1;
  reader_table[reader].pcsc.rsp_fd = -1;
  reader_table[reader].pcsc.pid = (pid_t)(-1);
#endif
  return reader;
}


static void
dump_reader_status (int reader)
{
  if (reader_table[reader].is_ccid)
    log_info ("reader slot %d: using ccid driver\n", reader);
  else if (reader_table[reader].is_ctapi)
    {
      log_info ("reader slot %d: %s\n", reader,
                reader_table[reader].status == 1? "Processor ICC present" :
                reader_table[reader].status == 0? "Memory ICC present" :
                "ICC not present" );
    }
  else
    {
      log_info ("reader slot %d: active protocol:", reader);
      if ((reader_table[reader].pcsc.protocol & PCSC_PROTOCOL_T0))
        log_printf (" T0");
      else if ((reader_table[reader].pcsc.protocol & PCSC_PROTOCOL_T1))
        log_printf (" T1");
      else if ((reader_table[reader].pcsc.protocol & PCSC_PROTOCOL_RAW))
        log_printf (" raw");
      log_printf ("\n");
    }

  if (reader_table[reader].status != -1)
    {
      log_info ("reader %d: ATR=", reader);
      log_printhex ("", reader_table[reader].atr,
                    reader_table[reader].atrlen);
    }
}



/* 
       ct API Interface 
 */

static const char *
ct_error_string (long err)
{
  switch (err)
    {
    case 0: return "okay";
    case -1: return "invalid data";
    case -8: return "ct error";
    case -10: return "transmission error";
    case -11: return "memory allocation error";
    case -128: return "HTSI error";
    default: return "unknown CT-API error";
    }
}

/* Wait for the card in READER and activate it.  Return -1 on error or
   0 on success. */
static int
ct_activate_card (int reader)
{
  int rc, count;

  for (count = 0; count < CARD_CONNECT_TIMEOUT; count++)
    {
      unsigned char dad[1], sad[1], cmd[11], buf[256];
      unsigned short buflen;

      if (count)
        ; /* FIXME: we should use a more reliable timer than sleep. */

      /* Check whether card has been inserted. */
      dad[0] = 1;     /* Destination address: CT. */    
      sad[0] = 2;     /* Source address: Host. */

      cmd[0] = 0x20;  /* Class byte. */
      cmd[1] = 0x13;  /* Request status. */
      cmd[2] = 0x00;  /* From kernel. */
      cmd[3] = 0x80;  /* Return card's DO. */
      cmd[4] = 0x00;

      buflen = DIM(buf);

      rc = CT_data (reader, dad, sad, 5, cmd, &buflen, buf);
      if (rc || buflen < 2 || buf[buflen-2] != 0x90)
        {
          log_error ("ct_activate_card: can't get status of reader %d: %s\n",
                     reader, ct_error_string (rc));
          return -1;
        }

      /* Connected, now activate the card. */           
      dad[0] = 1;    /* Destination address: CT. */    
      sad[0] = 2;    /* Source address: Host. */

      cmd[0] = 0x20;  /* Class byte. */
      cmd[1] = 0x12;  /* Request ICC. */
      cmd[2] = 0x01;  /* From first interface. */
      cmd[3] = 0x01;  /* Return card's ATR. */
      cmd[4] = 0x00;

      buflen = DIM(buf);

      rc = CT_data (reader, dad, sad, 5, cmd, &buflen, buf);
      if (rc || buflen < 2 || buf[buflen-2] != 0x90)
        {
          log_error ("ct_activate_card(%d): activation failed: %s\n",
                     reader, ct_error_string (rc));
          if (!rc)
            log_printhex ("  received data:", buf, buflen);
          return -1;
        }

      /* Store the type and the ATR. */
      if (buflen - 2 > DIM (reader_table[0].atr))
        {
          log_error ("ct_activate_card(%d): ATR too long\n", reader);
          return -1;
        }

      reader_table[reader].status = buf[buflen - 1];
      memcpy (reader_table[reader].atr, buf, buflen - 2);
      reader_table[reader].atrlen = buflen - 2;
      return 0;
    }
 
  log_info ("ct_activate_card(%d): timeout waiting for card\n", reader);
  return -1;
}


/* Open a reader and return an internal handle for it.  PORT is a
   non-negative value with the port number of the reader. USB readers
   do have port numbers starting at 32769. */
static int
open_ct_reader (int port)
{
  int rc, reader;

  if (port < 0 || port > 0xffff)
    {
      log_error ("open_ct_reader: invalid port %d requested\n", port);
      return -1;
    }
  reader = new_reader_slot ();
  if (reader == -1)
    return reader;
  reader_table[reader].port = port;

  rc = CT_init (reader, (unsigned short)port);
  if (rc)
    {
      log_error ("apdu_open_ct_reader failed on port %d: %s\n",
                 port, ct_error_string (rc));
      reader_table[reader].used = 0;
      return -1;
    }

  rc = ct_activate_card (reader);
  if (rc)
    {
      reader_table[reader].used = 0;
      return -1;
    }

  reader_table[reader].is_ctapi = 1;
  dump_reader_status (reader);
  return reader;
}

static int
close_ct_reader (int slot)
{
  CT_close (slot);
  reader_table[slot].used = 0;
  return 0;
}

static int
reset_ct_reader (int slot)
{
  return SW_HOST_NOT_SUPPORTED;
}


static int
ct_get_status (int slot, unsigned int *status)
{
  return SW_HOST_NOT_SUPPORTED;
}

/* Actually send the APDU of length APDULEN to SLOT and return a
   maximum of *BUFLEN data in BUFFER, the actual retruned size will be
   set to BUFLEN.  Returns: CT API error code. */
static int
ct_send_apdu (int slot, unsigned char *apdu, size_t apdulen,
              unsigned char *buffer, size_t *buflen)
{
  int rc;
  unsigned char dad[1], sad[1];
  unsigned short ctbuflen;
  
  dad[0] = 0;     /* Destination address: Card. */    
  sad[0] = 2;     /* Source address: Host. */
  ctbuflen = *buflen;
  if (DBG_CARD_IO)
    log_printhex ("  CT_data:", apdu, apdulen);
  rc = CT_data (slot, dad, sad, apdulen, apdu, &ctbuflen, buffer);
  *buflen = ctbuflen;

  /* FIXME: map the errorcodes to GNUPG ones, so that they can be
     shared between CTAPI and PCSC. */
  return rc;
}



#ifdef NEED_PCSC_WRAPPER
static int
writen (int fd, const void *buf, size_t nbytes)
{
  size_t nleft = nbytes;
  int nwritten;

/*   log_printhex (" writen:", buf, nbytes); */

  while (nleft > 0)
    {
#ifdef USE_GNU_PTH
      nwritten = pth_write (fd, buf, nleft);
#else
      nwritten = write (fd, buf, nleft);
#endif
      if (nwritten < 0 && errno == EINTR)
        continue;
      if (nwritten < 0)
        return -1;
      nleft -= nwritten;
      buf = (const char*)buf + nwritten;
    }
  return 0;
}

/* Read up to BUFLEN bytes from FD and return the number of bytes
   actually read in NREAD.  Returns -1 on error or 0 on success. */
static int
readn (int fd, void *buf, size_t buflen, size_t *nread)
{
  size_t nleft = buflen;
  int n;
/*   void *orig_buf = buf; */

  while (nleft > 0)
    {
#ifdef USE_GNU_PTH
      n = pth_read (fd, buf, nleft);
#else
      n = read (fd, buf, nleft);
#endif
      if (n < 0 && errno == EINTR) 
        continue;
      if (n < 0)
        return -1; /* read error. */
      if (!n)
        break; /* EOF */
      nleft -= n;
      buf = (char*)buf + n;
    }
  if (nread)
    *nread = buflen - nleft;

/*   log_printhex ("  readn:", orig_buf, *nread); */
    
  return 0;
}
#endif /*NEED_PCSC_WRAPPER*/

static const char *
pcsc_error_string (long err)
{
  const char *s;

  if (!err)
    return "okay";
  if ((err & 0x80100000) != 0x80100000)
    return "invalid PC/SC error code";
  err &= 0xffff;
  switch (err)
    {
    case 0x0002: s = "cancelled"; break;
    case 0x000e: s = "can't dispose"; break;
    case 0x0008: s = "insufficient buffer"; break;   
    case 0x0015: s = "invalid ATR"; break;
    case 0x0003: s = "invalid handle"; break;
    case 0x0004: s = "invalid parameter"; break; 
    case 0x0005: s = "invalid target"; break;
    case 0x0011: s = "invalid value"; break; 
    case 0x0006: s = "no memory"; break;  
    case 0x0013: s = "comm error"; break;      
    case 0x0001: s = "internal error"; break;     
    case 0x0014: s = "unknown error"; break; 
    case 0x0007: s = "waited too long"; break;  
    case 0x0009: s = "unknown reader"; break;
    case 0x000a: s = "timeout"; break; 
    case 0x000b: s = "sharing violation"; break;       
    case 0x000c: s = "no smartcard"; break;
    case 0x000d: s = "unknown card"; break;   
    case 0x000f: s = "proto mismatch"; break;          
    case 0x0010: s = "not ready"; break;               
    case 0x0012: s = "system cancelled"; break;        
    case 0x0016: s = "not transacted"; break;
    case 0x0017: s = "reader unavailable"; break; 
    case 0x0065: s = "unsupported card"; break;        
    case 0x0066: s = "unresponsive card"; break;       
    case 0x0067: s = "unpowered card"; break;          
    case 0x0068: s = "reset card"; break;              
    case 0x0069: s = "removed card"; break;            
    case 0x006a: s = "inserted card"; break;           
    case 0x001f: s = "unsupported feature"; break;     
    case 0x0019: s = "PCI too small"; break;           
    case 0x001a: s = "reader unsupported"; break;      
    case 0x001b: s = "duplicate reader"; break;        
    case 0x001c: s = "card unsupported"; break;        
    case 0x001d: s = "no service"; break;              
    case 0x001e: s = "service stopped"; break;      
    default:     s = "unknown PC/SC error code"; break;
    }
  return s;
}

/* 
       PC/SC Interface
 */

static int
open_pcsc_reader (const char *portstr)
{
#ifdef NEED_PCSC_WRAPPER
/* Open the PC/SC reader using the pcsc_wrapper program.  This is
   needed to cope with different thread models and other peculiarities
   of libpcsclite. */
  int slot;
  reader_table_t slotp;
  int fd, rp[2], wp[2];
  int n, i;
  pid_t pid;
  size_t len;
  unsigned char msgbuf[9];
  int err;

  slot = new_reader_slot ();
  if (slot == -1)
    return -1;
  slotp = reader_table + slot;

  /* Fire up the pcsc wrapper.  We don't use any fork/exec code from
     the common directy but implement it direclty so that this file
     may still be source copied. */
  
  if (pipe (rp) == -1)
    {
      log_error ("error creating a pipe: %s\n", strerror (errno));
      slotp->used = 0;
      return -1;
    }
  if (pipe (wp) == -1)
    {
      log_error ("error creating a pipe: %s\n", strerror (errno));
      close (rp[0]);
      close (rp[1]);
      slotp->used = 0;
      return -1;
    }
      
  pid = fork ();
  if (pid == -1)
    {
      log_error ("error forking process: %s\n", strerror (errno));
      close (rp[0]);
      close (rp[1]);
      close (wp[0]);
      close (wp[1]);
      slotp->used = 0;
      return -1;
    }
  slotp->pcsc.pid = pid;

  if (!pid)
    { /*
         === Child ===
       */

      /* Double fork. */
      pid = fork ();
      if (pid == -1)
        _exit (31); 
      if (pid)
        _exit (0); /* Immediate exit this parent, so that the child
                      gets cleaned up by the init process. */

      /* Connect our pipes. */
      if (wp[0] != 0 && dup2 (wp[0], 0) == -1)
        log_fatal ("dup2 stdin failed: %s\n", strerror (errno));
      if (rp[1] != 1 && dup2 (rp[1], 1) == -1)
        log_fatal ("dup2 stdout failed: %s\n", strerror (errno));
      
      /* Send stderr to the bit bucket. */
      fd = open ("/dev/null", O_WRONLY);
      if (fd == -1)
        log_fatal ("can't open `/dev/null': %s", strerror (errno));
      if (fd != 2 && dup2 (fd, 2) == -1)
        log_fatal ("dup2 stderr failed: %s\n", strerror (errno));

      /* Close all other files. */
      n = sysconf (_SC_OPEN_MAX);
      if (n < 0)
        n = MAX_OPEN_FDS;
      for (i=3; i < n; i++)
        close(i);
      errno = 0;

      execl (GNUPG_LIBDIR "/pcsc-wrapper",
             "pcsc-wrapper",
             "--",
             "1", /* API version */
             opt.pcsc_driver, /* Name of the PC/SC library. */
              NULL);
      _exit (31);
    }

  /* 
     === Parent ===
   */
  close (wp[0]);
  close (rp[1]);
  slotp->pcsc.req_fd = wp[1];
  slotp->pcsc.rsp_fd = rp[0];

  /* Wait for the intermediate child to terminate. */
  while ( (i=pth_waitpid (pid, NULL, 0)) == -1 && errno == EINTR)
    ;

  /* Now send the open request. */
  msgbuf[0] = 0x01; /* OPEN command. */
  len = portstr? strlen (portstr):0;
  msgbuf[1] = (len >> 24);
  msgbuf[2] = (len >> 16);
  msgbuf[3] = (len >>  8);
  msgbuf[4] = (len      );
  if ( writen (slotp->pcsc.req_fd, msgbuf, 5)
       || (portstr && writen (slotp->pcsc.req_fd, portstr, len)))
    {
      log_error ("error sending PC/SC OPEN request: %s\n",
                 strerror (errno));
      goto command_failed;
    }
  /* Read the response. */
  if ((i=readn (slotp->pcsc.rsp_fd, msgbuf, 9, &len)) || len != 9)
    {
      log_error ("error receiving PC/SC OPEN response: %s\n",
                 i? strerror (errno) : "premature EOF");
      goto command_failed;
    }
  len = (msgbuf[1] << 24) | (msgbuf[2] << 16) | (msgbuf[3] << 8 ) | msgbuf[4];
  if (msgbuf[0] != 0x81 || len < 4)
    {
      log_error ("invalid response header from PC/SC received\n");
      goto command_failed;
    }
  len -= 4; /* Already read the error code. */
  if (len > DIM (slotp->atr))
    {
      log_error ("PC/SC returned a too large ATR (len=%x)\n", len);
      goto command_failed;
    }
  err = (msgbuf[5] << 24) | (msgbuf[6] << 16) | (msgbuf[7] << 8 ) | msgbuf[8];
  if (err)
    {
      log_error ("PC/SC OPEN failed: %s\n", pcsc_error_string (err));
      goto command_failed;
    }
  n = len;
  if ((i=readn (slotp->pcsc.rsp_fd, slotp->atr, n, &len)) || len != n)
    {
      log_error ("error receiving PC/SC OPEN response: %s\n",
                 i? strerror (errno) : "premature EOF");
      goto command_failed;
    }
  slotp->atrlen = len;

  dump_reader_status (slot); 
  return slot;

 command_failed:
  close (slotp->pcsc.req_fd);
  close (slotp->pcsc.rsp_fd);
  slotp->pcsc.req_fd = -1;
  slotp->pcsc.rsp_fd = -1;
  kill (slotp->pcsc.pid, SIGTERM);
  slotp->pcsc.pid = (pid_t)(-1);
  slotp->used = 0;
  return -1;
#else /*!NEED_PCSC_WRAPPER */
  long err;
  int slot;
  char *list = NULL;
  unsigned long nreader, listlen, atrlen;
  char *p;
  unsigned long card_state, card_protocol;

  slot = new_reader_slot ();
  if (slot == -1)
    return -1;

  err = pcsc_establish_context (PCSC_SCOPE_SYSTEM, NULL, NULL,
                                &reader_table[slot].pcsc.context);
  if (err)
    {
      log_error ("pcsc_establish_context failed: %s (0x%lx)\n",
                 pcsc_error_string (err), err);
      reader_table[slot].used = 0;
      return -1;
    }
  
  err = pcsc_list_readers (reader_table[slot].pcsc.context,
                           NULL, NULL, &nreader);
  if (!err)
    {
      list = xtrymalloc (nreader+1); /* Better add 1 for safety reasons. */
      if (!list)
        {
          log_error ("error allocating memory for reader list\n");
          pcsc_release_context (reader_table[slot].pcsc.context);
          reader_table[slot].used = 0;
          return -1;
        }
      err = pcsc_list_readers (reader_table[slot].pcsc.context,
                               NULL, list, &nreader);
    }
  if (err)
    {
      log_error ("pcsc_list_readers failed: %s (0x%lx)\n",
                 pcsc_error_string (err), err);
      pcsc_release_context (reader_table[slot].pcsc.context);
      reader_table[slot].used = 0;
      xfree (list);
      return -1;
    }

  listlen = nreader;
  p = list;
  while (nreader)
    {
      if (!*p && !p[1])
        break;
      log_info ("detected reader `%s'\n", p);
      if (nreader < (strlen (p)+1))
        {
          log_error ("invalid response from pcsc_list_readers\n");
          break;
        }
      nreader -= strlen (p)+1;
      p += strlen (p) + 1;
    }

  err = pcsc_connect (reader_table[slot].pcsc.context,
                      portstr? portstr : list,
                      PCSC_SHARE_EXCLUSIVE,
                      PCSC_PROTOCOL_T0|PCSC_PROTOCOL_T1,
                      &reader_table[slot].pcsc.card,
                      &reader_table[slot].pcsc.protocol);
  if (err)
    {
      log_error ("pcsc_connect failed: %s (0x%lx)\n",
                  pcsc_error_string (err), err);
      pcsc_release_context (reader_table[slot].pcsc.context);
      reader_table[slot].used = 0;
      xfree (list);
      return -1;
    }      
  
  atrlen = 32;
  /* (We need to pass a dummy buffer.  We use LIST because it ought to
     be large enough.) */
  err = pcsc_status (reader_table[slot].pcsc.card,
                     list, &listlen,
                     &card_state, &card_protocol,
                     reader_table[slot].atr, &atrlen);
  xfree (list);
  if (err)
    {
      log_error ("pcsc_status failed: %s (0x%lx)\n",
                  pcsc_error_string (err), err);
      pcsc_release_context (reader_table[slot].pcsc.context);
      reader_table[slot].used = 0;
      return -1;
    }
  if (atrlen >= DIM (reader_table[0].atr))
    log_bug ("ATR returned by pcsc_status is too large\n");
  reader_table[slot].atrlen = atrlen;
/*   log_debug ("state    from pcsc_status: 0x%lx\n", card_state); */
/*   log_debug ("protocol from pcsc_status: 0x%lx\n", card_protocol); */

  dump_reader_status (slot); 
  return slot;
#endif /*!NEED_PCSC_WRAPPER */
}


static int
pcsc_get_status (int slot, unsigned int *status)
{
  return SW_HOST_NOT_SUPPORTED;
}

/* Actually send the APDU of length APDULEN to SLOT and return a
   maximum of *BUFLEN data in BUFFER, the actual returned size will be
   set to BUFLEN.  Returns: CT API error code. */
static int
pcsc_send_apdu (int slot, unsigned char *apdu, size_t apdulen,
                unsigned char *buffer, size_t *buflen)
{
#ifdef NEED_PCSC_WRAPPER
  long err;
  reader_table_t slotp;
  size_t len, full_len;
  int i, n;
  unsigned char msgbuf[9];

  if (DBG_CARD_IO)
    log_printhex ("  PCSC_data:", apdu, apdulen);

  slotp = reader_table + slot;

  if (slotp->pcsc.req_fd == -1 
      || slotp->pcsc.rsp_fd == -1 
      || slotp->pcsc.pid == (pid_t)(-1) )
    {
      log_error ("pcsc_send_apdu: pcsc-wrapper not running\n");
      return -1;
    }

  msgbuf[0] = 0x03; /* TRANSMIT command. */
  len = apdulen;
  msgbuf[1] = (len >> 24);
  msgbuf[2] = (len >> 16);
  msgbuf[3] = (len >>  8);
  msgbuf[4] = (len      );
  if ( writen (slotp->pcsc.req_fd, msgbuf, 5)
       || writen (slotp->pcsc.req_fd, apdu, len))
    {
      log_error ("error sending PC/SC TRANSMIT request: %s\n",
                 strerror (errno));
      goto command_failed;
    }

  /* Read the response. */
  if ((i=readn (slotp->pcsc.rsp_fd, msgbuf, 9, &len)) || len != 9)
    {
      log_error ("error receiving PC/SC TRANSMIT response: %s\n",
                 i? strerror (errno) : "premature EOF");
      goto command_failed;
    }
  len = (msgbuf[1] << 24) | (msgbuf[2] << 16) | (msgbuf[3] << 8 ) | msgbuf[4];
  if (msgbuf[0] != 0x81 || len < 4)
    {
      log_error ("invalid response header from PC/SC received\n");
      goto command_failed;
    }
  len -= 4; /* Already read the error code. */
  err = (msgbuf[5] << 24) | (msgbuf[6] << 16) | (msgbuf[7] << 8 ) | msgbuf[8];
  if (err)
    {
      log_error ("pcsc_transmit failed: %s (0x%lx)\n",
                 pcsc_error_string (err), err);
      return -1;
    }

   full_len = len;

   n = *buflen < len ? *buflen : len;
   if ((i=readn (slotp->pcsc.rsp_fd, buffer, n, &len)) || len != n)
     {
       log_error ("error receiving PC/SC TRANSMIT response: %s\n",
                  i? strerror (errno) : "premature EOF");
       goto command_failed;
     }
   *buflen = n;
   full_len -= len;
   if (full_len)
     {
       log_error ("pcsc_send_apdu: provided buffer too short - truncated\n");
       err = -1; 
     }
   /* We need to read any rest of the response, to keep the
      protocol runnng. */
   while (full_len)
     {
       unsigned char dummybuf[128];

       n = full_len < DIM (dummybuf) ? full_len : DIM (dummybuf);
       if ((i=readn (slotp->pcsc.rsp_fd, dummybuf, n, &len)) || len != n)
         {
           log_error ("error receiving PC/SC TRANSMIT response: %s\n",
                      i? strerror (errno) : "premature EOF");
           goto command_failed;
         }
       full_len -= n;
     }

   return err;

 command_failed:
  close (slotp->pcsc.req_fd);
  close (slotp->pcsc.rsp_fd);
  slotp->pcsc.req_fd = -1;
  slotp->pcsc.rsp_fd = -1;
  kill (slotp->pcsc.pid, SIGTERM);
  slotp->pcsc.pid = (pid_t)(-1);
  slotp->used = 0;
  return -1;

#else /*!NEED_PCSC_WRAPPER*/

  long err;
  struct pcsc_io_request_s send_pci;
  unsigned long recv_len;
  
  if (DBG_CARD_IO)
    log_printhex ("  PCSC_data:", apdu, apdulen);

  if ((reader_table[slot].pcsc.protocol & PCSC_PROTOCOL_T1))
      send_pci.protocol = PCSC_PROTOCOL_T1;
  else
      send_pci.protocol = PCSC_PROTOCOL_T0;
  send_pci.pci_len = sizeof send_pci;
  recv_len = *buflen;
  err = pcsc_transmit (reader_table[slot].pcsc.card,
                       &send_pci, apdu, apdulen,
                       NULL, buffer, &recv_len);
  *buflen = recv_len;
  if (err)
    log_error ("pcsc_transmit failed: %s (0x%lx)\n",
               pcsc_error_string (err), err);
  
  return err? -1:0; /* FIXME: Return appropriate error code. */
#endif /*!NEED_PCSC_WRAPPER*/
}


static int
close_pcsc_reader (int slot)
{
#ifdef NEED_PCSC_WRAPPER
  long err;
  reader_table_t slotp;
  size_t len;
  int i;
  unsigned char msgbuf[9];

  slotp = reader_table + slot;

  if (slotp->pcsc.req_fd == -1 
      || slotp->pcsc.rsp_fd == -1 
      || slotp->pcsc.pid == (pid_t)(-1) )
    {
      log_error ("close_pcsc_reader: pcsc-wrapper not running\n");
      return 0;
    }

  msgbuf[0] = 0x02; /* CLOSE command. */
  len = 0;
  msgbuf[1] = (len >> 24);
  msgbuf[2] = (len >> 16);
  msgbuf[3] = (len >>  8);
  msgbuf[4] = (len      );
  if ( writen (slotp->pcsc.req_fd, msgbuf, 5) )
    {
      log_error ("error sending PC/SC CLOSE request: %s\n",
                 strerror (errno));
      goto command_failed;
    }

  /* Read the response. */
  if ((i=readn (slotp->pcsc.rsp_fd, msgbuf, 9, &len)) || len != 9)
    {
      log_error ("error receiving PC/SC CLOSE response: %s\n",
                 i? strerror (errno) : "premature EOF");
      goto command_failed;
    }
  len = (msgbuf[1] << 24) | (msgbuf[2] << 16) | (msgbuf[3] << 8 ) | msgbuf[4];
  if (msgbuf[0] != 0x81 || len < 4)
    {
      log_error ("invalid response header from PC/SC received\n");
      goto command_failed;
    }
  len -= 4; /* Already read the error code. */
  err = (msgbuf[5] << 24) | (msgbuf[6] << 16) | (msgbuf[7] << 8 ) | msgbuf[8];
  if (err)
    log_error ("pcsc_close failed: %s (0x%lx)\n",
               pcsc_error_string (err), err);
  
  /* We will the wrapper in any case - errors are merely
     informational. */
  
 command_failed:
  close (slotp->pcsc.req_fd);
  close (slotp->pcsc.rsp_fd);
  slotp->pcsc.req_fd = -1;
  slotp->pcsc.rsp_fd = -1;
  kill (slotp->pcsc.pid, SIGTERM);
  slotp->pcsc.pid = (pid_t)(-1);
  slotp->used = 0;
  return 0;

#else /*!NEED_PCSC_WRAPPER*/

  pcsc_release_context (reader_table[slot].pcsc.context);
  reader_table[slot].used = 0;
  return 0;
#endif /*!NEED_PCSC_WRAPPER*/
}

static int
reset_pcsc_reader (int slot)
{
  return SW_HOST_NOT_SUPPORTED;
}





#ifdef HAVE_LIBUSB
/* 
     Internal CCID driver interface.
 */

static const char *
get_ccid_error_string (long err)
{
  if (!err)
    return "okay";
  else
    return "unknown CCID error";
}

static int
open_ccid_reader (void)
{
  int err;
  int slot;
  reader_table_t slotp;

  slot = new_reader_slot ();
  if (slot == -1)
    return -1;
  slotp = reader_table + slot;

  err = ccid_open_reader (&slotp->ccid.handle, 0);
  if (err)
    {
      slotp->used = 0;
      return -1;
    }

  err = ccid_get_atr (slotp->ccid.handle,
                      slotp->atr, sizeof slotp->atr, &slotp->atrlen);
  if (err)
    {
      slotp->used = 0;
      return -1;
    }

  slotp->is_ccid = 1;

  dump_reader_status (slot); 
  return slot;
}

static int
close_ccid_reader (int slot)
{
  ccid_close_reader (reader_table[slot].ccid.handle);
  reader_table[slot].used = 0;
  return 0;
}                       
  

static int
reset_ccid_reader (int slot)
{
  int err;
  reader_table_t slotp = reader_table + slot;
  unsigned char atr[33];
  size_t atrlen;

  err = ccid_get_atr (slotp->ccid.handle, atr, sizeof atr, &atrlen);
  if (err)
    return -1;
  /* If the reset was successful, update the ATR. */
  assert (sizeof slotp->atr >= sizeof atr);
  slotp->atrlen = atrlen;
  memcpy (slotp->atr, atr, atrlen);
  dump_reader_status (slot); 
  return 0;
}                       
  

static int
get_status_ccid (int slot, unsigned int *status)
{
  int rc;
  int bits;

  rc = ccid_slot_status (reader_table[slot].ccid.handle, &bits);
  if (rc)
    return -1;

  if (bits == 0)
    *status = 1|2|4;
  else if (bits == 1)
    *status = 2;
  else 
    *status = 0;

  return 0;
}


/* Actually send the APDU of length APDULEN to SLOT and return a
   maximum of *BUFLEN data in BUFFER, the actual returned size will be
   set to BUFLEN.  Returns: Internal CCID driver error code. */
static int
send_apdu_ccid (int slot, unsigned char *apdu, size_t apdulen,
                unsigned char *buffer, size_t *buflen)
{
  long err;
  size_t maxbuflen;

  if (DBG_CARD_IO)
    log_printhex ("  APDU_data:", apdu, apdulen);

  maxbuflen = *buflen;
  err = ccid_transceive (reader_table[slot].ccid.handle,
                         apdu, apdulen,
                         buffer, maxbuflen, buflen);
  if (err)
    log_error ("ccid_transceive failed: (0x%lx)\n",
               err);
  
  return err? -1:0; /* FIXME: Return appropriate error code. */
}

#endif /* HAVE_LIBUSB */



#ifdef HAVE_OPENSC
/* 
     OpenSC Interface.

     This uses the OpenSC primitives to send APDUs.  We need this
     because we can't mix OpenSC and native (i.e. ctAPI or PC/SC)
     access to a card for resource conflict reasons.
 */

static int
open_osc_reader (int portno)
{
  int err;
  int slot;
  reader_table_t slotp;

  slot = new_reader_slot ();
  if (slot == -1)
    return -1;
  slotp = reader_table + slot;

  err = sc_establish_context (&slotp->osc.ctx, "scdaemon");
  if (err)
    {
      log_error ("failed to establish SC context: %s\n", sc_strerror (err));
      slotp->used = 0;
      return -1;
    }
  if (portno < 0 || portno >= slotp->osc.ctx->reader_count)
    {
      log_error ("no card reader available\n");
      sc_release_context (slotp->osc.ctx);
      slotp->used = 0;
      return -1;
    }

  /* Redirect to our logging facility. */
  slotp->osc.ctx->error_file = log_get_stream ();
  slotp->osc.ctx->debug = opt.debug_sc;
  slotp->osc.ctx->debug_file = log_get_stream ();

  if (sc_detect_card_presence (slotp->osc.ctx->reader[portno], 0) != 1)
    {
      log_error ("no card present\n");
      sc_release_context (slotp->osc.ctx);
      slotp->used = 0;
      return -1;
    }
  
  /* We want the standard ISO driver. */
  /*FIXME: OpenSC does not like "iso7816", so we use EMV for now. */
  err = sc_set_card_driver(slotp->osc.ctx, "emv");
  if (err)
    {
      log_error ("failed to select the iso7816 driver: %s\n",
                 sc_strerror (err));
      sc_release_context (slotp->osc.ctx);
      slotp->used = 0;
      return -1;
    }

  /* Now connect the card and hope that OpenSC won't try to be too
     smart. */
  err = sc_connect_card (slotp->osc.ctx->reader[portno], 0,
                         &slotp->osc.scard);
  if (err)
    {
      log_error ("failed to connect card in reader %d: %s\n",
                 portno, sc_strerror (err));
      sc_release_context (slotp->osc.ctx);
      slotp->used = 0;
      return -1;
    }
  if (opt.verbose)
    log_info ("connected to card in opensc reader %d using driver `%s'\n",
              portno, slotp->osc.scard->driver->name);

  err = sc_lock (slotp->osc.scard);
  if (err)
    {
      log_error ("can't lock card in reader %d: %s\n",
                 portno, sc_strerror (err));
      sc_disconnect_card (slotp->osc.scard, 0);
      sc_release_context (slotp->osc.ctx);
      slotp->used = 0;
      return -1;
    }

  if (slotp->osc.scard->atr_len >= DIM (slotp->atr))
    log_bug ("ATR returned by opensc is too large\n");
  slotp->atrlen = slotp->osc.scard->atr_len;
  memcpy (slotp->atr, slotp->osc.scard->atr, slotp->atrlen);

  slotp->is_osc = 1;

  dump_reader_status (slot); 
  return slot;
}


static int
close_osc_reader (int slot)
{
  /* FIXME: Implement. */
  reader_table[slot].used = 0;
  return 0;
}

static int
reset_osc_reader (int slot)
{
  return SW_HOST_NOT_SUPPORTED;
}


static int
ocsc_get_status (int slot, unsigned int *status)
{
  return SW_HOST_NOT_SUPPORTED;
}


/* Actually send the APDU of length APDULEN to SLOT and return a
   maximum of *BUFLEN data in BUFFER, the actual returned size will be
   set to BUFLEN.  Returns: OpenSC error code. */
static int
osc_send_apdu (int slot, unsigned char *apdu, size_t apdulen,
                unsigned char *buffer, size_t *buflen)
{
  long err;
  struct sc_apdu a;
  unsigned char data[SC_MAX_APDU_BUFFER_SIZE];
  unsigned char result[SC_MAX_APDU_BUFFER_SIZE];

  if (DBG_CARD_IO)
    log_printhex ("  APDU_data:", apdu, apdulen);

  if (apdulen < 4)
    {
      log_error ("osc_send_apdu: APDU is too short\n");
      return SC_ERROR_CMD_TOO_SHORT;
    }

  memset(&a, 0, sizeof a);
  a.cla = *apdu++;
  a.ins = *apdu++;
  a.p1 = *apdu++;
  a.p2 = *apdu++;
  apdulen -= 4;

  if (!apdulen)
    a.cse = SC_APDU_CASE_1;
  else if (apdulen == 1) 
    {
      a.le = *apdu? *apdu : 256;
      apdu++; apdulen--;
      a.cse = SC_APDU_CASE_2_SHORT;
    }
  else
    {
      a.lc = *apdu++; apdulen--;
      if (apdulen < a.lc)
        {
          log_error ("osc_send_apdu: APDU shorter than specified in Lc\n");
          return SC_ERROR_CMD_TOO_SHORT;

        }
      memcpy(data, apdu, a.lc);
      apdu += a.lc; apdulen -= a.lc;

      a.data = data;
      a.datalen = a.lc;
      
      if (!apdulen)
        a.cse = SC_APDU_CASE_3_SHORT;
      else
        {
          a.le = *apdu? *apdu : 256;
          apdu++; apdulen--;
          if (apdulen)
            {
              log_error ("osc_send_apdu: APDU larger than specified\n");
              return SC_ERROR_CMD_TOO_LONG;
            }
          a.cse = SC_APDU_CASE_4_SHORT;
        }
    }

  a.resp = result;
  a.resplen = DIM(result);

  err = sc_transmit_apdu (reader_table[slot].osc.scard, &a);
  if (err)
    {
      log_error ("sc_apdu_transmit failed: %s\n", sc_strerror (err));
      return err;
    }

  if (*buflen < 2 || a.resplen > *buflen - 2)
    {
      log_error ("osc_send_apdu: provided buffer too short to store result\n");
      return SC_ERROR_BUFFER_TOO_SMALL;
    }
  memcpy (buffer, a.resp, a.resplen);
  buffer[a.resplen] = a.sw1;
  buffer[a.resplen+1] = a.sw2;
  *buflen = a.resplen + 2;
  return 0;
}

#endif /* HAVE_OPENSC */



/* 
       Driver Access
 */


static int
lock_slot (int slot)
{
#ifdef USE_GNU_PTH
  if (!pth_mutex_acquire (&reader_table[slot].lock, 0, NULL))
    {
      log_error ("failed to acquire apdu lock: %s\n", strerror (errno));
      return SW_HOST_LOCKING_FAILED;
    }
#endif /*USE_GNU_PTH*/
  return 0;
}

static int
trylock_slot (int slot)
{
#ifdef USE_GNU_PTH
  if (!pth_mutex_acquire (&reader_table[slot].lock, TRUE, NULL))
    {
      if (errno == EBUSY)
        return SW_HOST_BUSY;
      log_error ("failed to acquire apdu lock: %s\n", strerror (errno));
      return SW_HOST_LOCKING_FAILED;
    }
#endif /*USE_GNU_PTH*/
  return 0;
}

static void
unlock_slot (int slot)
{
#ifdef USE_GNU_PTH
  if (!pth_mutex_release (&reader_table[slot].lock))
    log_error ("failed to release apdu lock: %s\n", strerror (errno));
#endif /*USE_GNU_PTH*/
}


/* Open the reader and return an internal slot number or -1 on
   error. If PORTSTR is NULL we default to a suitable port (for ctAPI:
   the first USB reader.  For PC/SC the first listed reader).  If
   OpenSC support is compiled in, we first try to use OpenSC. */
int
apdu_open_reader (const char *portstr)
{
  static int pcsc_api_loaded, ct_api_loaded;

#ifdef HAVE_LIBUSB
  if (!opt.disable_ccid)
    {
      int slot;

      slot = open_ccid_reader ();
      if (slot != -1)
        return slot; /* got one */
    }
#endif /* HAVE_LIBUSB */

#ifdef HAVE_OPENSC
  if (!opt.disable_opensc)
    {
      int port = portstr? atoi (portstr) : 0;

      return open_osc_reader (port);
    }
#endif /* HAVE_OPENSC */  


  if (opt.ctapi_driver && *opt.ctapi_driver)
    {
      int port = portstr? atoi (portstr) : 32768;

      if (!ct_api_loaded)
        {
          void *handle;
          
          handle = dlopen (opt.ctapi_driver, RTLD_LAZY);
          if (!handle)
            {
              log_error ("apdu_open_reader: failed to open driver: %s\n",
                         dlerror ());
              return -1;
            }
          CT_init = dlsym (handle, "CT_init");
          CT_data = dlsym (handle, "CT_data");
          CT_close = dlsym (handle, "CT_close");
          if (!CT_init || !CT_data || !CT_close)
            {
              log_error ("apdu_open_reader: invalid CT-API driver\n");
              dlclose (handle);
              return -1;
            }
          ct_api_loaded = 1;
        }
      return open_ct_reader (port);
    }

  
  /* No ctAPI configured, so lets try the PC/SC API */
  if (!pcsc_api_loaded)
    {
#ifndef NEED_PCSC_WRAPPER
      void *handle;

      handle = dlopen (opt.pcsc_driver, RTLD_LAZY);
      if (!handle)
        {
          log_error ("apdu_open_reader: failed to open driver `%s': %s\n",
                     opt.pcsc_driver, dlerror ());
          return -1;
        }

      pcsc_establish_context = dlsym (handle, "SCardEstablishContext");
      pcsc_release_context   = dlsym (handle, "SCardReleaseContext");
      pcsc_list_readers      = dlsym (handle, "SCardListReaders");
#ifdef _WIN32
      if (!pcsc_list_readers)
        pcsc_list_readers    = dlsym (handle, "SCardListReadersA");
#endif
      pcsc_connect           = dlsym (handle, "SCardConnect");
#ifdef _WIN32
      if (!pcsc_connect)
        pcsc_connect         = dlsym (handle, "SCardConnectA");
#endif
      pcsc_disconnect        = dlsym (handle, "SCardDisconnect");
      pcsc_status            = dlsym (handle, "SCardStatus");
#ifdef _WIN32
      if (!pcsc_status)
        pcsc_status          = dlsym (handle, "SCardStatusA");
#endif
      pcsc_begin_transaction = dlsym (handle, "SCardBeginTransaction");
      pcsc_end_transaction   = dlsym (handle, "SCardEndTransaction");
      pcsc_transmit          = dlsym (handle, "SCardTransmit");
      pcsc_set_timeout       = dlsym (handle, "SCardSetTimeout");

      if (!pcsc_establish_context
          || !pcsc_release_context  
          || !pcsc_list_readers     
          || !pcsc_connect          
          || !pcsc_disconnect
          || !pcsc_status
          || !pcsc_begin_transaction
          || !pcsc_end_transaction
          || !pcsc_transmit         
          /* || !pcsc_set_timeout */)
        {
          /* Note that set_timeout is currently not used and also not
             available under Windows. */
          log_error ("apdu_open_reader: invalid PC/SC driver "
                     "(%d%d%d%d%d%d%d%d%d%d)\n",
                     !!pcsc_establish_context,
                     !!pcsc_release_context,  
                     !!pcsc_list_readers,     
                     !!pcsc_connect,          
                     !!pcsc_disconnect,
                     !!pcsc_status,
                     !!pcsc_begin_transaction,
                     !!pcsc_end_transaction,
                     !!pcsc_transmit,         
                     !!pcsc_set_timeout );
          dlclose (handle);
          return -1;
        }
#endif /*!NEED_PCSC_WRAPPER*/  
      pcsc_api_loaded = 1;
    }

  return open_pcsc_reader (portstr);
}


int
apdu_close_reader (int slot)
{
  if (slot < 0 || slot >= MAX_READER || !reader_table[slot].used )
    return SW_HOST_NO_DRIVER;
  if (reader_table[slot].is_ctapi)
    return close_ct_reader (slot);
#ifdef HAVE_LIBUSB
  else if (reader_table[slot].is_ccid)
    return close_ccid_reader (slot);
#endif
#ifdef HAVE_OPENSC
  else if (reader_table[slot].is_osc)
    return close_osc_reader (slot);
#endif
  else
    return close_pcsc_reader (slot);
}

/* Enumerate all readers and return information on whether this reader
   is in use.  The caller should start with SLOT set to 0 and
   increment it with each call until an error is returned. */
int
apdu_enum_reader (int slot, int *used)
{
  if (slot < 0 || slot >= MAX_READER)
    return SW_HOST_NO_DRIVER;
  *used = reader_table[slot].used;
  return 0;
}

/* Do a reset for the card in reader at SLOT. */
int
apdu_reset (int slot)
{
  int sw;

  if (slot < 0 || slot >= MAX_READER || !reader_table[slot].used )
    return SW_HOST_NO_DRIVER;
  
  if ((sw = lock_slot (slot)))
    return sw;

  if (reader_table[slot].is_ctapi)
    sw = reset_ct_reader (slot);
#ifdef HAVE_LIBUSB
  else if (reader_table[slot].is_ccid)
    sw = reset_ccid_reader (slot);
#endif
#ifdef HAVE_OPENSC
  else if (reader_table[slot].is_osc)
    sw = reset_osc_reader (slot);
#endif
  else
    sw = reset_pcsc_reader (slot);

  unlock_slot (slot);
  return sw;
}


unsigned char *
apdu_get_atr (int slot, size_t *atrlen)
{
  char *buf;

  if (slot < 0 || slot >= MAX_READER || !reader_table[slot].used )
    return NULL;
  
  buf = xtrymalloc (reader_table[slot].atrlen);
  if (!buf)
    return NULL;
  memcpy (buf, reader_table[slot].atr, reader_table[slot].atrlen);
  *atrlen = reader_table[slot].atrlen;
  return buf;
}

  
    
static const char *
error_string (int slot, long rc)
{
  if (slot < 0 || slot >= MAX_READER || !reader_table[slot].used )
    return "[invalid slot]";
  if (reader_table[slot].is_ctapi)
    return ct_error_string (rc);
#ifdef HAVE_LIBUSB
  else if (reader_table[slot].is_ccid)
    return get_ccid_error_string (rc);
#endif
#ifdef HAVE_OPENSC
  else if (reader_table[slot].is_osc)
    return sc_strerror (rc);
#endif
  else
    return pcsc_error_string (rc);
}


/* Retrieve the status for SLOT. The function does obnly wait fot the
   card to become available if HANG is set to true. On success the
   bits in STATUS will be set to

     bit 0 = card present and usable
     bit 1 = card present
     bit 2 = card active
     bit 3 = card access locked [not yet implemented]

   For must application, tetsing bit 0 is sufficient.

   CHANGED will receive the value of the counter tracking the number
   of card insertions.  This value may be used to detect a card
   change.
*/
int
apdu_get_status (int slot, int hang,
                 unsigned int *status, unsigned int *changed)
{
  int sw;
  unsigned int s;

  if (slot < 0 || slot >= MAX_READER || !reader_table[slot].used )
    return SW_HOST_NO_DRIVER;

  if ((sw = hang? lock_slot (slot) : trylock_slot (slot)))
    return sw;

  if (reader_table[slot].is_ctapi)
    sw = ct_get_status (slot, &s);
#ifdef HAVE_LIBUSB
  else if (reader_table[slot].is_ccid)
    sw = get_status_ccid (slot, &s);
#endif
#ifdef HAVE_OPENSC
  else if (reader_table[slot].is_osc)
    sw = osc_get_status (slot, &s);
#endif
  else
    sw = pcsc_get_status (slot, &s);

  unlock_slot (slot);

  if (sw)
    return sw;

  if (status)
    *status = s;
  if (changed)
    *changed = reader_table[slot].change_counter;
  return 0;
}


/* Dispatcher for the actual send_apdu function. Note, that this
   function should be called in locked state. */
static int
send_apdu (int slot, unsigned char *apdu, size_t apdulen,
           unsigned char *buffer, size_t *buflen)
{
  if (slot < 0 || slot >= MAX_READER || !reader_table[slot].used )
    return SW_HOST_NO_DRIVER;
  if (reader_table[slot].is_ctapi)
    return ct_send_apdu (slot, apdu, apdulen, buffer, buflen);
#ifdef HAVE_LIBUSB
  else if (reader_table[slot].is_ccid)
    return send_apdu_ccid (slot, apdu, apdulen, buffer, buflen);
#endif
#ifdef HAVE_OPENSC
  else if (reader_table[slot].is_osc)
    return osc_send_apdu (slot, apdu, apdulen, buffer, buflen);
#endif
  else
    return pcsc_send_apdu (slot, apdu, apdulen, buffer, buflen);
}

/* Send an APDU to the card in SLOT.  The APDU is created from all
   given parameters: CLASS, INS, P0, P1, LC, DATA, LE.  A value of -1
   for LC won't sent this field and the data field; in this case DATA
   must also be passed as NULL.  The return value is the status word
   or -1 for an invalid SLOT or other non card related error.  If
   RETBUF is not NULL, it will receive an allocated buffer with the
   returned data.  The length of that data will be put into
   *RETBUFLEN.  The caller is reponsible for releasing the buffer even
   in case of errors.  */
int 
apdu_send_le(int slot, int class, int ins, int p0, int p1,
             int lc, const char *data, int le,
             unsigned char **retbuf, size_t *retbuflen)
{
  unsigned char result[256+10]; /* 10 extra in case of bugs in the driver. */
  size_t resultlen = 256;
  unsigned char apdu[5+256+1];
  size_t apdulen;
  int sw;
  long rc; /* we need a long here due to PC/SC. */

  if (slot < 0 || slot >= MAX_READER || !reader_table[slot].used )
    return SW_HOST_NO_DRIVER;

  if (DBG_CARD_IO)
    log_debug ("send apdu: c=%02X i=%02X p0=%02X p1=%02X lc=%d le=%d\n",
               class, ins, p0, p1, lc, le);

  if (lc != -1 && (lc > 255 || lc < 0))
    return SW_WRONG_LENGTH; 
  if (le != -1 && (le > 256 || le < 1))
    return SW_WRONG_LENGTH; 
  if ((!data && lc != -1) || (data && lc == -1))
    return SW_HOST_INV_VALUE;

  if ((sw = lock_slot (slot)))
    return sw;

  apdulen = 0;
  apdu[apdulen++] = class;
  apdu[apdulen++] = ins;
  apdu[apdulen++] = p0;
  apdu[apdulen++] = p1;
  if (lc != -1)
    {
      apdu[apdulen++] = lc;
      memcpy (apdu+apdulen, data, lc);
      apdulen += lc;
    }
  if (le != -1)
    apdu[apdulen++] = le; /* Truncation is okay becuase 0 means 256. */
  assert (sizeof (apdu) >= apdulen);
  /* As safeguard don't pass any garbage from the stack to the driver. */
  memset (apdu+apdulen, 0, sizeof (apdu) - apdulen);
  rc = send_apdu (slot, apdu, apdulen, result, &resultlen);
  if (rc || resultlen < 2)
    {
      log_error ("apdu_send_simple(%d) failed: %s\n",
                 slot, error_string (slot, rc));
      unlock_slot (slot);
      return SW_HOST_INCOMPLETE_CARD_RESPONSE;
    }
  sw = (result[resultlen-2] << 8) | result[resultlen-1];
  /* store away the returned data but strip the statusword. */
  resultlen -= 2;
  if (DBG_CARD_IO)
    {
      log_debug (" response: sw=%04X  datalen=%d\n", sw, resultlen);
      if ( !retbuf && (sw == SW_SUCCESS || (sw & 0xff00) == SW_MORE_DATA))
        log_printhex ("     dump: ", result, resultlen);
    }

  if (sw == SW_SUCCESS || sw == SW_EOF_REACHED)
    {
      if (retbuf)
        {
          *retbuf = xtrymalloc (resultlen? resultlen : 1);
          if (!*retbuf)
            {
              unlock_slot (slot);
              return SW_HOST_OUT_OF_CORE;
            }
          *retbuflen = resultlen;
          memcpy (*retbuf, result, resultlen);
        }
    }
  else if ((sw & 0xff00) == SW_MORE_DATA)
    {
      unsigned char *p = NULL, *tmp;
      size_t bufsize = 4096;

      /* It is likely that we need to return much more data, so we
         start off with a large buffer. */
      if (retbuf)
        {
          *retbuf = p = xtrymalloc (bufsize);
          if (!*retbuf)
            {
              unlock_slot (slot);
              return SW_HOST_OUT_OF_CORE;
            }
          assert (resultlen < bufsize);
          memcpy (p, result, resultlen);
          p += resultlen;
        }

      do
        {
          int len = (sw & 0x00ff);
          
          log_debug ("apdu_send_simple(%d): %d more bytes available\n",
                     slot, len);
          apdulen = 0;
          apdu[apdulen++] = class;
          apdu[apdulen++] = 0xC0;
          apdu[apdulen++] = 0;
          apdu[apdulen++] = 0;
          apdu[apdulen++] = len; 
          memset (apdu+apdulen, 0, sizeof (apdu) - apdulen);
          rc = send_apdu (slot, apdu, apdulen, result, &resultlen);
          if (rc || resultlen < 2)
            {
              log_error ("apdu_send_simple(%d) for get response failed: %s\n",
                         slot, error_string (slot, rc));
              unlock_slot (slot);
              return SW_HOST_INCOMPLETE_CARD_RESPONSE;
            }
          sw = (result[resultlen-2] << 8) | result[resultlen-1];
          resultlen -= 2;
          if (DBG_CARD_IO)
            {
              log_debug ("     more: sw=%04X  datalen=%d\n", sw, resultlen);
              if (!retbuf && (sw==SW_SUCCESS || (sw&0xff00)==SW_MORE_DATA))
                log_printhex ("     dump: ", result, resultlen);
            }

          if ((sw & 0xff00) == SW_MORE_DATA || sw == SW_SUCCESS)
            {
              if (retbuf)
                {
                  if (p - *retbuf + resultlen > bufsize)
                    {
                      bufsize += resultlen > 4096? resultlen: 4096;
                      tmp = xtryrealloc (*retbuf, bufsize);
                      if (!tmp)
                        {
                          unlock_slot (slot);
                          return SW_HOST_OUT_OF_CORE;
                        }
                      p = tmp + (p - *retbuf);
                      *retbuf = tmp;
                    }
                  memcpy (p, result, resultlen);
                  p += resultlen;
                }
            }
          else
            log_info ("apdu_send_simple(%d) "
                      "got unexpected status %04X from get response\n",
                      slot, sw);
        }
      while ((sw & 0xff00) == SW_MORE_DATA);
      
      if (retbuf)
        {
          *retbuflen = p - *retbuf;
          tmp = xtryrealloc (*retbuf, *retbuflen);
          if (tmp)
            *retbuf = tmp;
        }
    }

  unlock_slot (slot);

  if (DBG_CARD_IO && retbuf && sw == SW_SUCCESS)
    log_printhex ("      dump: ", *retbuf, *retbuflen);
 
  return sw;
}

/* Send an APDU to the card in SLOT.  The APDU is created from all
   given parameters: CLASS, INS, P0, P1, LC, DATA.  A value of -1 for
   LC won't sent this field and the data field; in this case DATA must
   also be passed as NULL. The return value is the status word or -1
   for an invalid SLOT or other non card related error.  If RETBUF is
   not NULL, it will receive an allocated buffer with the returned
   data.  The length of that data will be put into *RETBUFLEN.  The
   caller is reponsible for releasing the buffer even in case of
   errors.  */
int 
apdu_send (int slot, int class, int ins, int p0, int p1,
           int lc, const char *data, unsigned char **retbuf, size_t *retbuflen)
{
  return apdu_send_le (slot, class, ins, p0, p1, lc, data, 256, 
                       retbuf, retbuflen);
}

/* Send an APDU to the card in SLOT.  The APDU is created from all
   given parameters: CLASS, INS, P0, P1, LC, DATA.  A value of -1 for
   LC won't sent this field and the data field; in this case DATA must
   also be passed as NULL. The return value is the status word or -1
   for an invalid SLOT or other non card related error.  No data will be
   returned. */
int 
apdu_send_simple (int slot, int class, int ins, int p0, int p1,
                  int lc, const char *data)
{
  return apdu_send_le (slot, class, ins, p0, p1, lc, data, -1, NULL, NULL);
}