Imported Upstream version 2.0.19upstream/2.0.19

1 files changed, 2327 insertions, 0 deletions

diff --git a/scd/command.c b/scd/command.c
new file mode 100644
index 0000000..52b22c6
--- /dev/null
+++ b/scd/command.c
@@ -0,0 +1,2327 @@
+/* command.c - SCdaemon command handler
+ * Copyright (C) 2001, 2002, 2003, 2004, 2005,
+ *               2007, 2008, 2009  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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <signal.h>
+#ifdef USE_GNU_PTH
+# include <pth.h>
+#endif
+
+#include "scdaemon.h"
+#include <assuan.h>
+#include <ksba.h>
+#include "app-common.h"
+#include "apdu.h" /* Required for apdu_*_reader (). */
+#include "exechelp.h"
+#ifdef HAVE_LIBUSB
+#include "ccid-driver.h"
+#endif
+
+/* Maximum length allowed as a PIN; used for INQUIRE NEEDPIN */
+#define MAXLEN_PIN 100
+
+/* Maximum allowed size of key data as used in inquiries. */
+#define MAXLEN_KEYDATA 4096
+
+/* Maximum allowed size of certificate data as used in inquiries. */
+#define MAXLEN_CERTDATA 16384
+
+
+#define set_error(e,t) assuan_set_error (ctx, gpg_error (e), (t))
+
+
+/* Macro to flag a removed card.  ENODEV is also tested to catch teh
+   case of a removed reader.  */
+#define TEST_CARD_REMOVAL(c,r)                              \
+       do {                                                 \
+          int _r = (r);                                     \
+          if (gpg_err_code (_r) == GPG_ERR_CARD_NOT_PRESENT \
+              || gpg_err_code (_r) == GPG_ERR_CARD_REMOVED  \
+              || gpg_err_code (_r) == GPG_ERR_ENODEV )      \
+            update_card_removed ((c)->reader_slot, 1);      \
+       } while (0)
+
+#define IS_LOCKED(c)                                                     \
+     (locked_session && locked_session != (c)->server_local              \
+      && (c)->reader_slot != -1 && locked_session->ctrl_backlink         \
+      && (c)->reader_slot == locked_session->ctrl_backlink->reader_slot)
+
+
+/* Flag indicating that the reader has been disabled.  */
+static int reader_disabled;
+
+
+/* This structure is used to keep track of open readers (slots). */
+struct slot_status_s 
+{
+  int valid;  /* True if the other objects are valid. */
+  int slot;   /* Slot number of the reader or -1 if not open. */
+
+  int reset_failed; /* A reset failed. */
+
+  int any;    /* Flag indicating whether any status check has been
+                 done.  This is set once to indicate that the status
+                 tracking for the slot has been initialized.  */
+  unsigned int status;  /* Last status of the slot. */
+  unsigned int changed; /* Last change counter of the slot. */
+};
+
+
+/* Data used to associate an Assuan context with local server data.
+   This object describes the local properties of one session.  */
+struct server_local_s 
+{
+  /* We keep a list of all active sessions with the anchor at
+     SESSION_LIST (see below).  This field is used for linking. */
+  struct server_local_s *next_session; 
+
+  /* This object is usually assigned to a CTRL object (which is
+     globally visible).  While enumerating all sessions we sometimes
+     need to access data of the CTRL object; thus we keep a
+     backpointer here. */
+  ctrl_t ctrl_backlink;
+
+  /* The Assuan context used by this session/server. */
+  assuan_context_t assuan_ctx;
+
+#ifdef HAVE_W32_SYSTEM
+  unsigned long event_signal;   /* Or 0 if not used. */
+#else
+  int event_signal;             /* Or 0 if not used. */
+#endif
+  
+  /* True if the card has been removed and a reset is required to
+     continue operation. */
+  int card_removed;        
+
+  /* Flag indicating that the application context needs to be released
+     at the next opportunity.  */
+  int app_ctx_marked_for_release;
+
+  /* A disconnect command has been sent.  */
+  int disconnect_allowed;
+
+  /* If set to true we will be terminate ourself at the end of the
+     this session.  */
+  int stopme;  
+
+};
+
+
+/* The table with information on all used slots.  FIXME: This is a
+   different slot number than the one used by the APDU layer, and
+   should be renamed.  */
+static struct slot_status_s slot_table[10];
+
+
+/* To keep track of all running sessions, we link all active server
+   contexts and the anchor in this variable.  */
+static struct server_local_s *session_list;
+
+/* If a session has been locked we store a link to its server object
+   in this variable. */
+static struct server_local_s *locked_session;
+
+/* While doing a reset we need to make sure that the ticker does not
+   call scd_update_reader_status_file while we are using it. */
+static pth_mutex_t status_file_update_lock;
+
+
+/*-- Local prototypes --*/
+static void update_reader_status_file (int set_card_removed_flag);
+
+
+
+
+/* This function must be called once to initialize this module.  This
+   has to be done before a second thread is spawned.  We can't do the
+   static initialization because Pth emulation code might not be able
+   to do a static init; in particular, it is not possible for W32. */
+void
+initialize_module_command (void)
+{
+  static int initialized;
+
+  if (!initialized)
+    {
+      if (pth_mutex_init (&status_file_update_lock))
+        initialized = 1;
+    }
+}
+
+
+/* Update the CARD_REMOVED element of all sessions using the reader
+   given by SLOT to VALUE.  */
+static void
+update_card_removed (int slot, int value)
+{
+  struct server_local_s *sl;
+
+  for (sl=session_list; sl; sl = sl->next_session)
+    if (sl->ctrl_backlink
+        && sl->ctrl_backlink->reader_slot == slot)
+      {
+        sl->card_removed = value;
+      }
+  /* Let the card application layer know about the removal.  */
+  if (value)
+    application_notify_card_reset (slot);
+}
+
+
+
+/* Check whether the option NAME appears in LINE.  Returns 1 or 0. */
+static int
+has_option (const char *line, const char *name)
+{
+  const char *s;
+  int n = strlen (name);
+
+  s = strstr (line, name);
+  return (s && (s == line || spacep (s-1)) && (!s[n] || spacep (s+n)));
+}
+
+/* Same as has_option but does only test for the name of the option
+   and ignores an argument, i.e. with NAME being "--hash" it would
+   return a pointer for "--hash" as well as for "--hash=foo".  If
+   there is no such option NULL is returned.  The pointer returned
+   points right behind the option name, this may be an equal sign, Nul
+   or a space.  */
+static const char *
+has_option_name (const char *line, const char *name)
+{
+  const char *s;
+  int n = strlen (name);
+
+  s = strstr (line, name);
+  return (s && (s == line || spacep (s-1))
+          && (!s[n] || spacep (s+n) || s[n] == '=')) ? (s+n) : NULL;
+}
+
+
+/* Skip over options.  It is assumed that leading spaces have been
+   removed (this is the case for lines passed to a handler from
+   assuan).  Blanks after the options are also removed. */
+static char *
+skip_options (char *line)
+{
+  while ( *line == '-' && line[1] == '-' )
+    {
+      while (*line && !spacep (line))
+        line++;
+      while (spacep (line))
+        line++;
+    }
+  return line;
+}
+
+
+
+/* Convert the STRING into a newly allocated buffer while translating
+   the hex numbers.  Stops at the first invalid character.  Blanks and
+   colons are allowed to separate the hex digits.  Returns NULL on
+   error or a newly malloced buffer and its length in LENGTH.  */
+static unsigned char *
+hex_to_buffer (const char *string, size_t *r_length)
+{
+  unsigned char *buffer;
+  const char *s;
+  size_t n;
+
+  buffer = xtrymalloc (strlen (string)+1);
+  if (!buffer)
+    return NULL;
+  for (s=string, n=0; *s; s++)
+    {
+      if (spacep (s) || *s == ':') 
+        continue;
+      if (hexdigitp (s) && hexdigitp (s+1))
+        {
+          buffer[n++] = xtoi_2 (s);
+          s++;
+        }
+      else
+        break;
+    }
+  *r_length = n;
+  return buffer;
+}
+
+
+
+/* Reset the card and free the application context.  With SEND_RESET
+   set to true actually send a RESET to the reader; this is the normal
+   way of calling the function.  */
+static void
+do_reset (ctrl_t ctrl, int send_reset)
+{
+  int slot = ctrl->reader_slot;
+
+  if (!(slot == -1 || (slot >= 0 && slot < DIM(slot_table))))
+    BUG ();
+
+  /* If there is an active application, release it.  Tell all other
+     sessions using the same application to release the
+     application.  */
+  if (ctrl->app_ctx)
+    {
+      release_application (ctrl->app_ctx);
+      ctrl->app_ctx = NULL;
+      if (send_reset)
+        {
+          struct server_local_s *sl;
+          
+          for (sl=session_list; sl; sl = sl->next_session)
+            if (sl->ctrl_backlink
+                && sl->ctrl_backlink->reader_slot == slot)
+              {
+                sl->app_ctx_marked_for_release = 1;
+              }
+        }
+    }
+
+  /* If we want a real reset for the card, send the reset APDU and
+     tell the application layer about it.  */
+  if (slot != -1 && send_reset && !IS_LOCKED (ctrl) )
+    {
+      if (apdu_reset (slot)) 
+        {
+          slot_table[slot].valid = 0;
+        }
+      application_notify_card_reset (slot);
+    }
+
+  /* If we hold a lock, unlock now. */
+  if (locked_session && ctrl->server_local == locked_session)
+    {
+      locked_session = NULL;
+      log_info ("implicitly unlocking due to RESET\n");
+    }
+
+  /* Reset the card removed flag for the current reader.  We need to
+     take the lock here so that the ticker thread won't concurrently
+     try to update the file.  Calling update_reader_status_file is
+     required to get hold of the new status of the card in the slot
+     table.  */
+  if (!pth_mutex_acquire (&status_file_update_lock, 0, NULL))
+    {
+      log_error ("failed to acquire status_fle_update lock\n");
+      ctrl->reader_slot = -1;
+      return;
+    }
+  update_reader_status_file (0);  /* Update slot status table.  */
+  update_card_removed (slot, 0);  /* Clear card_removed flag.  */
+  if (!pth_mutex_release (&status_file_update_lock))
+    log_error ("failed to release status_file_update lock\n");
+
+  /* Do this last, so that the update_card_removed above does its job.  */
+  ctrl->reader_slot = -1;
+}
+
+
+static gpg_error_t
+reset_notify (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx); 
+
+  (void) line;
+
+  do_reset (ctrl, 1);
+  return 0;
+}
+
+
+static gpg_error_t
+option_handler (assuan_context_t ctx, const char *key, const char *value)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+
+  if (!strcmp (key, "event-signal"))
+    {
+      /* A value of 0 is allowed to reset the event signal. */
+#ifdef HAVE_W32_SYSTEM
+      if (!*value)
+        return gpg_error (GPG_ERR_ASS_PARAMETER);
+      ctrl->server_local->event_signal = strtoul (value, NULL, 16);
+#else
+      int i = *value? atoi (value) : -1;
+      if (i < 0)
+        return gpg_error (GPG_ERR_ASS_PARAMETER);
+      ctrl->server_local->event_signal = i;
+#endif
+    }
+
+ return 0;
+}
+
+
+/* Return the slot of the current reader or open the reader if no
+   other sessions are using a reader.  Note, that we currently support
+   only one reader but most of the code (except for this function)
+   should be able to cope with several readers.  */
+static int
+get_reader_slot (void)
+{
+  struct slot_status_s *ss;
+
+  ss = &slot_table[0]; /* One reader for now. */
+
+  /* Initialize the item if needed. */
+  if (!ss->valid)
+    {
+      ss->slot = -1;
+      ss->valid = 1;
+    }
+
+  /* Try to open the reader. */
+  if (ss->slot == -1)
+    {
+      int no_service_flag;
+      ss->slot = apdu_open_reader (opt.reader_port, &no_service_flag);
+
+      /* If we still don't have a slot, we have no readers.
+	 Invalidate for now until a reader is attached. */
+      if(ss->slot == -1)
+	{
+	  ss->valid = 0;
+	}
+
+      if (no_service_flag)
+        {
+          log_info ("no card services - disabling scdaemon\n");
+          reader_disabled = 1;
+        }
+    }
+
+  /* Return the slot_table index.  */
+  return 0;
+}
+
+/* If the card has not yet been opened, do it.  Note that this
+   function returns an Assuan error, so don't map the error a second
+   time.  */
+static gpg_error_t
+open_card (ctrl_t ctrl, const char *apptype)
+{
+  gpg_error_t err;
+  int slot;
+
+  if (reader_disabled)
+    return gpg_error (GPG_ERR_NOT_OPERATIONAL);
+
+  /* If we ever got a card not present error code, return that.  Only
+     the SERIALNO command and a reset are able to clear from that
+     state. */
+  if (ctrl->server_local->card_removed)
+    return gpg_error (GPG_ERR_CARD_REMOVED);
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  /* If the application has been marked for release do it now.  We
+     can't do it immediately in do_reset because the application may
+     still be in use.  */
+  if (ctrl->server_local->app_ctx_marked_for_release)
+    {
+      ctrl->server_local->app_ctx_marked_for_release = 0;
+      release_application (ctrl->app_ctx);
+      ctrl->app_ctx = NULL;
+    }
+
+  /* If we are already initialized for one specific application we
+     need to check that the client didn't requested a specific
+     application different from the one in use before we continue. */
+  if (ctrl->app_ctx)
+    return check_application_conflict (ctrl, apptype);
+
+  /* Setup the slot and select the application.  */
+  if (ctrl->reader_slot != -1)
+    slot = ctrl->reader_slot;
+  else
+    slot = get_reader_slot ();
+  ctrl->reader_slot = slot;
+  if (slot == -1)
+    err = gpg_error (reader_disabled? GPG_ERR_NOT_OPERATIONAL: GPG_ERR_CARD);
+  else
+    {
+      /* Fixme: We should move the apdu_connect call to
+         select_application.  */
+      int sw;
+
+      ctrl->server_local->disconnect_allowed = 0;
+      sw = apdu_connect (slot);
+      if (sw && sw != SW_HOST_ALREADY_CONNECTED)
+        {
+          if (sw == SW_HOST_NO_CARD)
+            err = gpg_error (GPG_ERR_CARD_NOT_PRESENT);
+          else
+            err = gpg_error (GPG_ERR_CARD);
+	}
+      else
+        err = select_application (ctrl, slot, apptype, &ctrl->app_ctx);
+    }
+
+  TEST_CARD_REMOVAL (ctrl, err);
+  return err;
+}
+
+
+static const char hlp_serialno[] = 
+  "SERIALNO [<apptype>]\n"
+  "\n"
+  "Return the serial number of the card using a status reponse.  This\n"
+  "function should be used to check for the presence of a card.\n"
+  "\n"
+  "If APPTYPE is given, an application of that type is selected and an\n"
+  "error is returned if the application is not supported or available.\n"
+  "The default is to auto-select the application using a hardwired\n"
+  "preference system.  Note, that a future extension to this function\n"
+  "may allow to specify a list and order of applications to try.\n"
+  "\n"
+  "This function is special in that it can be used to reset the card.\n"
+  "Most other functions will return an error when a card change has\n"
+  "been detected and the use of this function is therefore required.\n"
+  "\n"
+  "Background: We want to keep the client clear of handling card\n"
+  "changes between operations; i.e. the client can assume that all\n"
+  "operations are done on the same card unless he calls this function.";
+static gpg_error_t
+cmd_serialno (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc = 0;
+  char *serial_and_stamp;
+  char *serial;
+  time_t stamp;
+
+  /* Clear the remove flag so that the open_card is able to reread it.  */
+  if (!reader_disabled && ctrl->server_local->card_removed)
+    {
+      if ( IS_LOCKED (ctrl) )
+        return gpg_error (GPG_ERR_LOCKED);
+      do_reset (ctrl, 1);
+    }
+
+  if ((rc = open_card (ctrl, *line? line:NULL)))
+    return rc;
+
+  rc = app_get_serial_and_stamp (ctrl->app_ctx, &serial, &stamp);
+  if (rc)
+    return rc;
+
+  rc = estream_asprintf (&serial_and_stamp, "%s %lu",
+                         serial, (unsigned long)stamp);
+  xfree (serial);
+  if (rc < 0)
+    return out_of_core ();
+  rc = 0;
+  assuan_write_status (ctx, "SERIALNO", serial_and_stamp);
+  xfree (serial_and_stamp);
+  return 0;
+}
+
+
+static const char hlp_learn[] = 
+  "LEARN [--force] [--keypairinfo]\n"
+  "\n"
+  "Learn all useful information of the currently inserted card.  When\n"
+  "used without the force options, the command might do an INQUIRE\n"
+  "like this:\n"
+  "\n"
+  "   INQUIRE KNOWNCARDP <hexstring_with_serialNumber> <timestamp>\n"
+  "\n"
+  "The client should just send an \"END\" if the processing should go on\n"
+  "or a \"CANCEL\" to force the function to terminate with a Cancel\n"
+  "error message.\n"
+  "\n"
+  "With the option --keypairinfo only KEYPARIINFO lstatus lines are\n"
+  "returned.\n"
+  "\n"
+  "The response of this command is a list of status lines formatted as\n"
+  "this:\n"
+  "\n"
+  "  S APPTYPE <apptype>\n"
+  "\n"
+  "This returns the type of the application, currently the strings:\n"
+  "\n"
+  "    P15     = PKCS-15 structure used\n"
+  "    DINSIG  = DIN SIG\n"
+  "    OPENPGP = OpenPGP card\n"
+  "    NKS     = NetKey card\n"
+  "\n"
+  "are implemented.  These strings are aliases for the AID\n"
+  "\n"
+  "  S KEYPAIRINFO <hexstring_with_keygrip> <hexstring_with_id>\n"
+  "\n"
+  "If there is no certificate yet stored on the card a single 'X' is\n"
+  "returned as the keygrip.  In addition to the keypair info, information\n"
+  "about all certificates stored on the card is also returned:\n"
+  "\n"
+  "  S CERTINFO <certtype> <hexstring_with_id>\n"
+  "\n"
+  "Where CERTTYPE is a number indicating the type of certificate:\n"
+  "   0   := Unknown\n"
+  "   100 := Regular X.509 cert\n"
+  "   101 := Trusted X.509 cert\n"
+  "   102 := Useful X.509 cert\n"
+  "   110 := Root CA cert in a special format (e.g. DINSIG)\n"
+  "   111 := Root CA cert as standard X509 cert.\n"
+  "\n"
+  "For certain cards, more information will be returned:\n"
+  "\n"
+  "  S KEY-FPR <no> <hexstring>\n"
+  "\n"
+  "For OpenPGP cards this returns the stored fingerprints of the\n"
+  "keys. This can be used check whether a key is available on the\n"
+  "card.  NO may be 1, 2 or 3.\n"
+  "\n"
+  "  S CA-FPR <no> <hexstring>\n"
+  "\n"
+  "Similar to above, these are the fingerprints of keys assumed to be\n"
+  "ultimately trusted.\n"
+  "\n"
+  "  S DISP-NAME <name_of_card_holder>\n"
+  "\n"
+  "The name of the card holder as stored on the card; percent\n"
+  "escaping takes place, spaces are encoded as '+'\n"
+  "\n"
+  "  S PUBKEY-URL <url>\n"
+  "\n"
+  "The URL to be used for locating the entire public key.\n"
+  "  \n"
+  "Note, that this function may even be used on a locked card.";
+static gpg_error_t
+cmd_learn (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc = 0;
+  int only_keypairinfo = has_option (line, "--keypairinfo");
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  /* Unless the force option is used we try a shortcut by identifying
+     the card using a serial number and inquiring the client with
+     that. The client may choose to cancel the operation if he already
+     knows about this card */
+  if (!only_keypairinfo)
+    {
+      char *serial_and_stamp;
+      char *serial;
+      time_t stamp;
+      
+      rc = app_get_serial_and_stamp (ctrl->app_ctx, &serial, &stamp);
+      if (rc)
+        return rc;
+      rc = estream_asprintf (&serial_and_stamp, "%s %lu",
+                             serial, (unsigned long)stamp);
+      xfree (serial);
+      if (rc < 0)
+        return out_of_core ();
+      rc = 0;
+      assuan_write_status (ctx, "SERIALNO", serial_and_stamp);
+      
+      if (!has_option (line, "--force"))
+        {
+          char *command;
+          
+          rc = estream_asprintf (&command, "KNOWNCARDP %s", serial_and_stamp);
+          if (rc < 0)
+            {
+              xfree (serial_and_stamp);
+              return out_of_core ();
+            }
+          rc = 0;
+          rc = assuan_inquire (ctx, command, NULL, NULL, 0); 
+          xfree (command);
+          if (rc)
+            {
+              if (gpg_err_code (rc) != GPG_ERR_ASS_CANCELED)
+                log_error ("inquire KNOWNCARDP failed: %s\n",
+                           gpg_strerror (rc));
+              xfree (serial_and_stamp);
+              return rc; 
+            }
+          /* Not canceled, so we have to proceeed.  */
+        }
+      xfree (serial_and_stamp);
+    }
+  
+  /* Let the application print out its collection of useful status
+     information. */
+  if (!rc)
+    rc = app_write_learn_status (ctrl->app_ctx, ctrl, only_keypairinfo);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+
+static const char hlp_readcert[] =
+  "READCERT <hexified_certid>|<keyid>\n"
+  "\n"
+  "Note, that this function may even be used on a locked card.";
+static gpg_error_t
+cmd_readcert (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  unsigned char *cert;
+  size_t ncert;
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  line = xstrdup (line); /* Need a copy of the line. */
+  rc = app_readcert (ctrl->app_ctx, line, &cert, &ncert);
+  if (rc)
+    log_error ("app_readcert failed: %s\n", gpg_strerror (rc));
+  xfree (line);
+  line = NULL;
+  if (!rc)
+    {
+      rc = assuan_send_data (ctx, cert, ncert);
+      xfree (cert);
+      if (rc)
+        return rc;
+    }
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_readkey[] = 
+  "READKEY <keyid>\n"
+  "\n"
+  "Return the public key for the given cert or key ID as a standard\n"
+  "S-expression.\n"
+  "\n"
+  "Note, that this function may even be used on a locked card.";
+static gpg_error_t
+cmd_readkey (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  unsigned char *cert = NULL;
+  size_t ncert, n;
+  ksba_cert_t kc = NULL;
+  ksba_sexp_t p;
+  unsigned char *pk;
+  size_t pklen;
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  line = xstrdup (line); /* Need a copy of the line. */
+  /* If the application supports the READKEY function we use that.
+     Otherwise we use the old way by extracting it from the
+     certificate.  */
+  rc = app_readkey (ctrl->app_ctx, line, &pk, &pklen);
+  if (!rc)
+    { /* Yeah, got that key - send it back.  */
+      rc = assuan_send_data (ctx, pk, pklen);
+      xfree (pk);
+      xfree (line);
+      line = NULL;
+      goto leave;
+    }
+
+  if (gpg_err_code (rc) != GPG_ERR_UNSUPPORTED_OPERATION)
+    log_error ("app_readkey failed: %s\n", gpg_strerror (rc));
+  else  
+    {
+      rc = app_readcert (ctrl->app_ctx, line, &cert, &ncert);
+      if (rc)
+        log_error ("app_readcert failed: %s\n", gpg_strerror (rc));
+    }
+  xfree (line);
+  line = NULL;
+  if (rc)
+    goto leave;
+      
+  rc = ksba_cert_new (&kc);
+  if (rc)
+    {
+      xfree (cert);
+      goto leave;
+    }
+  rc = ksba_cert_init_from_mem (kc, cert, ncert);
+  if (rc)
+    {
+      log_error ("failed to parse the certificate: %s\n", gpg_strerror (rc));
+      goto leave;
+    }
+
+  p = ksba_cert_get_public_key (kc);
+  if (!p)
+    {
+      rc = gpg_error (GPG_ERR_NO_PUBKEY);
+      goto leave;
+    }
+
+  n = gcry_sexp_canon_len (p, 0, NULL, NULL);
+  rc = assuan_send_data (ctx, p, n);
+  xfree (p);
+
+
+ leave:
+  ksba_cert_release (kc);
+  xfree (cert);
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+
+static const char hlp_setdata[] = 
+  "SETDATA <hexstring> \n"
+  "\n"
+  "The client should use this command to tell us the data he want to sign.";
+static gpg_error_t
+cmd_setdata (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int n;
+  char *p;
+  unsigned char *buf;
+
+  if (locked_session && locked_session != ctrl->server_local)
+    return gpg_error (GPG_ERR_LOCKED);
+
+  /* Parse the hexstring. */
+  for (p=line,n=0; hexdigitp (p); p++, n++)
+    ;
+  if (*p)
+    return set_error (GPG_ERR_ASS_PARAMETER, "invalid hexstring");
+  if (!n)
+    return set_error (GPG_ERR_ASS_PARAMETER, "no data given");
+  if ((n&1))
+    return set_error (GPG_ERR_ASS_PARAMETER, "odd number of digits");
+  n /= 2;
+  buf = xtrymalloc (n);
+  if (!buf)
+    return out_of_core ();
+
+  ctrl->in_data.value = buf;
+  ctrl->in_data.valuelen = n;
+  for (p=line, n=0; n < ctrl->in_data.valuelen; p += 2, n++)
+    buf[n] = xtoi_2 (p);
+  return 0;
+}
+
+
+
+static gpg_error_t 
+pin_cb (void *opaque, const char *info, char **retstr)
+{
+  assuan_context_t ctx = opaque;
+  char *command;
+  int rc;
+  unsigned char *value;
+  size_t valuelen;
+
+  if (!retstr)
+    {
+      /* We prompt for keypad entry.  To make sure that the popup has
+         been show we use an inquire and not just a status message.
+         We ignore any value returned.  */
+      if (info)
+        {
+          log_debug ("prompting for keypad entry '%s'\n", info);
+          rc = estream_asprintf (&command, "POPUPKEYPADPROMPT %s", info);
+          if (rc < 0)
+            return gpg_error (gpg_err_code_from_errno (errno));
+          rc = assuan_inquire (ctx, command, &value, &valuelen, MAXLEN_PIN); 
+          xfree (command);  
+        }
+      else
+        {
+          log_debug ("dismiss keypad entry prompt\n");
+          rc = assuan_inquire (ctx, "DISMISSKEYPADPROMPT",
+                               &value, &valuelen, MAXLEN_PIN); 
+        }
+      if (!rc)
+        xfree (value);
+      return rc;
+    }
+
+  *retstr = NULL;
+  log_debug ("asking for PIN '%s'\n", info);
+
+  rc = estream_asprintf (&command, "NEEDPIN %s", info);
+  if (rc < 0)
+    return gpg_error (gpg_err_code_from_errno (errno));
+
+  /* Fixme: Write an inquire function which returns the result in
+     secure memory and check all further handling of the PIN. */
+  rc = assuan_inquire (ctx, command, &value, &valuelen, MAXLEN_PIN); 
+  xfree (command);  
+  if (rc)
+    return rc;
+
+  if (!valuelen || value[valuelen-1])
+    {
+      /* We require that the returned value is an UTF-8 string */
+      xfree (value);
+      return gpg_error (GPG_ERR_INV_RESPONSE);
+    }
+  *retstr = (char*)value;
+  return 0;
+}
+
+
+static const char hlp_pksign[] = 
+  "PKSIGN [--hash=[rmd160|sha{1,224,256,384,512}|md5]] <hexified_id>\n"
+  "\n"
+  "The --hash option is optional; the default is SHA1.";
+static gpg_error_t
+cmd_pksign (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  unsigned char *outdata;
+  size_t outdatalen;
+  char *keyidstr;
+  int hash_algo;
+
+  if (has_option (line, "--hash=rmd160"))
+    hash_algo = GCRY_MD_RMD160;
+  else if (has_option (line, "--hash=sha1"))
+    hash_algo = GCRY_MD_SHA1;
+  else if (has_option (line, "--hash=sha224"))
+    hash_algo = GCRY_MD_SHA224;
+  else if (has_option (line, "--hash=sha256"))
+    hash_algo = GCRY_MD_SHA256;
+  else if (has_option (line, "--hash=sha384"))
+    hash_algo = GCRY_MD_SHA384;
+  else if (has_option (line, "--hash=sha512"))
+    hash_algo = GCRY_MD_SHA512;
+  else if (has_option (line, "--hash=md5"))
+    hash_algo = GCRY_MD_MD5;
+  else if (!strstr (line, "--"))
+    hash_algo = GCRY_MD_SHA1; 
+  else
+    return set_error (GPG_ERR_ASS_PARAMETER, "invalid hash algorithm");
+
+  line = skip_options (line);
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  /* We have to use a copy of the key ID because the function may use
+     the pin_cb which in turn uses the assuan line buffer and thus
+     overwriting the original line with the keyid */
+  keyidstr = xtrystrdup (line);
+  if (!keyidstr)
+    return out_of_core ();
+  
+  rc = app_sign (ctrl->app_ctx,
+                 keyidstr, hash_algo,
+                 pin_cb, ctx,
+                 ctrl->in_data.value, ctrl->in_data.valuelen,
+                 &outdata, &outdatalen);
+
+  xfree (keyidstr);
+  if (rc)
+    {
+      log_error ("app_sign failed: %s\n", gpg_strerror (rc));
+    }
+  else
+    {
+      rc = assuan_send_data (ctx, outdata, outdatalen);
+      xfree (outdata);
+      if (rc)
+        return rc; /* that is already an assuan error code */
+    }
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_pkauth[] = 
+  "PKAUTH <hexified_id>";
+static gpg_error_t
+cmd_pkauth (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  unsigned char *outdata;
+  size_t outdatalen;
+  char *keyidstr;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (!ctrl->app_ctx)
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+ /* We have to use a copy of the key ID because the function may use
+     the pin_cb which in turn uses the assuan line buffer and thus
+     overwriting the original line with the keyid */
+  keyidstr = xtrystrdup (line);
+  if (!keyidstr)
+    return out_of_core ();
+  
+  rc = app_auth (ctrl->app_ctx,
+                 keyidstr,
+                 pin_cb, ctx,
+                 ctrl->in_data.value, ctrl->in_data.valuelen,
+                 &outdata, &outdatalen);
+  xfree (keyidstr);
+  if (rc)
+    {
+      log_error ("app_auth failed: %s\n", gpg_strerror (rc));
+    }
+  else
+    {
+      rc = assuan_send_data (ctx, outdata, outdatalen);
+      xfree (outdata);
+      if (rc)
+        return rc; /* that is already an assuan error code */
+    }
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_pkdecrypt[] = 
+  "PKDECRYPT <hexified_id>";
+static gpg_error_t
+cmd_pkdecrypt (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  unsigned char *outdata;
+  size_t outdatalen;
+  char *keyidstr;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  keyidstr = xtrystrdup (line);
+  if (!keyidstr)
+    return out_of_core ();
+  rc = app_decipher (ctrl->app_ctx,
+                     keyidstr, 
+                     pin_cb, ctx,
+                     ctrl->in_data.value, ctrl->in_data.valuelen,
+                     &outdata, &outdatalen);
+
+  xfree (keyidstr);
+  if (rc)
+    {
+      log_error ("app_decipher failed: %s\n", gpg_strerror (rc));
+    }
+  else
+    {
+      rc = assuan_send_data (ctx, outdata, outdatalen);
+      xfree (outdata);
+      if (rc)
+        return rc; /* that is already an assuan error code */
+    }
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_getattr[] = 
+  "GETATTR <name>\n"
+  "\n"
+  "This command is used to retrieve data from a smartcard.  The\n"
+  "allowed names depend on the currently selected smartcard\n"
+  "application.  NAME must be percent and '+' escaped.  The value is\n"
+  "returned through status message, see the LEARN command for details.\n"
+  "\n"
+  "However, the current implementation assumes that Name is not escaped;\n"
+  "this works as long as noone uses arbitrary escaping. \n"
+  "\n"
+  "Note, that this function may even be used on a locked card.";
+static gpg_error_t
+cmd_getattr (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  const char *keyword;
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  keyword = line;
+  for (; *line && !spacep (line); line++)
+    ;
+  if (*line)
+      *line++ = 0;
+
+  /* (We ignore any garbage for now.) */
+
+  /* FIXME: Applications should not return sensitive data if the card
+     is locked.  */
+  rc = app_getattr (ctrl->app_ctx, ctrl, keyword);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_setattr[] = 
+  "SETATTR <name> <value> \n"
+  "\n"
+  "This command is used to store data on a a smartcard.  The allowed\n"
+  "names and values are depend on the currently selected smartcard\n"
+  "application.  NAME and VALUE must be percent and '+' escaped.\n"
+  "\n"
+  "However, the current implementation assumes that NAME is not\n"
+  "escaped; this works as long as noone uses arbitrary escaping.\n"
+  "\n"
+  "A PIN will be requested for most NAMEs.  See the corresponding\n"
+  "setattr function of the actually used application (app-*.c) for\n"
+  "details.";
+static gpg_error_t
+cmd_setattr (assuan_context_t ctx, char *orig_line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  char *keyword;
+  int keywordlen;
+  size_t nbytes;
+  char *line, *linebuf;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  /* We need to use a copy of LINE, because PIN_CB uses the same
+     context and thus reuses the Assuan provided LINE. */
+  line = linebuf = xtrystrdup (orig_line);
+  if (!line)
+    return out_of_core ();
+
+  keyword = line;
+  for (keywordlen=0; *line && !spacep (line); line++, keywordlen++)
+    ;
+  if (*line)
+      *line++ = 0;
+  while (spacep (line))
+    line++;
+  nbytes = percent_plus_unescape_inplace (line, 0);
+
+  rc = app_setattr (ctrl->app_ctx, keyword, pin_cb, ctx,
+                    (const unsigned char*)line, nbytes);
+  xfree (linebuf);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_writecert[] = 
+  "WRITECERT <hexified_certid>\n"
+  "\n"
+  "This command is used to store a certifciate on a smartcard.  The\n"
+  "allowed certids depend on the currently selected smartcard\n"
+  "application. The actual certifciate is requested using the inquiry\n"
+  "\"CERTDATA\" and needs to be provided in its raw (e.g. DER) form.\n"
+  "\n"
+  "In almost all cases a a PIN will be requested.  See the related\n"
+  "writecert function of the actually used application (app-*.c) for\n"
+  "details.";
+static gpg_error_t
+cmd_writecert (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  char *certid;
+  unsigned char *certdata;
+  size_t certdatalen;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  line = skip_options (line);
+
+  if (!*line)
+    return set_error (GPG_ERR_ASS_PARAMETER, "no certid given");
+  certid = line;
+  while (*line && !spacep (line))
+    line++;
+  *line = 0;
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (!ctrl->app_ctx)
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+  certid = xtrystrdup (certid);
+  if (!certid)
+    return out_of_core ();
+
+  /* Now get the actual keydata. */
+  rc = assuan_inquire (ctx, "CERTDATA",
+                       &certdata, &certdatalen, MAXLEN_CERTDATA);
+  if (rc)
+    {
+      xfree (certid);
+      return rc;
+    }
+
+  /* Write the certificate to the card. */
+  rc = app_writecert (ctrl->app_ctx, ctrl, certid, 
+                      pin_cb, ctx, certdata, certdatalen);
+  xfree (certid);
+  xfree (certdata);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_writekey[] = 
+  "WRITEKEY [--force] <keyid> \n"
+  "\n"
+  "This command is used to store a secret key on a a smartcard.  The\n"
+  "allowed keyids depend on the currently selected smartcard\n"
+  "application. The actual keydata is requested using the inquiry\n"
+  "\"KEYDATA\" and need to be provided without any protection.  With\n"
+  "--force set an existing key under this KEYID will get overwritten.\n"
+  "The keydata is expected to be the usual canonical encoded\n"
+  "S-expression.\n"
+  "\n"
+  "A PIN will be requested for most NAMEs.  See the corresponding\n"
+  "writekey function of the actually used application (app-*.c) for\n"
+  "details.";
+static gpg_error_t
+cmd_writekey (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  char *keyid;
+  int force = has_option (line, "--force");
+  unsigned char *keydata;
+  size_t keydatalen;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  line = skip_options (line);
+
+  if (!*line)
+    return set_error (GPG_ERR_ASS_PARAMETER, "no keyid given");
+  keyid = line;
+  while (*line && !spacep (line))
+    line++;
+  *line = 0;
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (!ctrl->app_ctx)
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+  keyid = xtrystrdup (keyid);
+  if (!keyid)
+    return out_of_core ();
+
+  /* Now get the actual keydata. */
+  assuan_begin_confidential (ctx);
+  rc = assuan_inquire (ctx, "KEYDATA", &keydata, &keydatalen, MAXLEN_KEYDATA);
+  assuan_end_confidential (ctx);
+  if (rc)
+    {
+      xfree (keyid);
+      return rc;
+    }
+
+  /* Write the key to the card. */
+  rc = app_writekey (ctrl->app_ctx, ctrl, keyid, force? 1:0,
+                     pin_cb, ctx, keydata, keydatalen);
+  xfree (keyid);
+  xfree (keydata);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_genkey[] = 
+  "GENKEY [--force] [--timestamp=<isodate>] <no>\n"
+  "\n"
+  "Generate a key on-card identified by NO, which is application\n"
+  "specific.  Return values are application specific.  For OpenPGP\n"
+  "cards 3 status lines are returned:\n"
+  "\n"
+  "  S KEY-FPR  <hexstring>\n"
+  "  S KEY-CREATED-AT <seconds_since_epoch>\n"
+  "  S KEY-DATA [-|p|n] <hexdata>\n"
+  "\n"
+  "  'p' and 'n' are the names of the RSA parameters; '-' is used to\n"
+  "  indicate that HEXDATA is the first chunk of a parameter given\n"
+  "  by the next KEY-DATA.\n"
+  "\n"
+  "--force is required to overwrite an already existing key.  The\n"
+  "KEY-CREATED-AT is required for further processing because it is\n"
+  "part of the hashed key material for the fingerprint.\n"
+  "\n"
+  "If --timestamp is given an OpenPGP key will be created using this\n"
+  "value.  The value needs to be in ISO Format; e.g.\n"
+  "\"--timestamp=20030316T120000\" and after 1970-01-01 00:00:00.\n"
+  "\n"
+  "The public part of the key can also later be retrieved using the\n"
+  "READKEY command.";
+static gpg_error_t
+cmd_genkey (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  char *keyno;
+  int force;
+  const char *s;
+  time_t timestamp;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  force = has_option (line, "--force");
+
+  if ((s=has_option_name (line, "--timestamp")))
+    {
+      if (*s != '=')
+        return set_error (GPG_ERR_ASS_PARAMETER, "missing value for option");
+      timestamp = isotime2epoch (s+1);
+      if (timestamp < 1)
+        return set_error (GPG_ERR_ASS_PARAMETER, "invalid time value");
+    }
+  else
+    timestamp = 0;
+
+
+  line = skip_options (line);
+  if (!*line)
+    return set_error (GPG_ERR_ASS_PARAMETER, "no key number given");
+  keyno = line;
+  while (*line && !spacep (line))
+    line++;
+  *line = 0;
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (!ctrl->app_ctx)
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+  keyno = xtrystrdup (keyno);
+  if (!keyno)
+    return out_of_core ();
+  rc = app_genkey (ctrl->app_ctx, ctrl, keyno, force? 1:0,
+                   timestamp, pin_cb, ctx);
+  xfree (keyno);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_random[] = 
+  "RANDOM <nbytes>\n"
+  "\n"
+  "Get NBYTES of random from the card and send them back as data.\n"
+  "This usually involves EEPROM write on the card and thus excessive\n"
+  "use of this command may destroy the card.\n"
+  "\n"
+  "Note, that this function may be even be used on a locked card.";
+static gpg_error_t
+cmd_random (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  size_t nbytes;
+  unsigned char *buffer;
+
+  if (!*line)
+    return set_error (GPG_ERR_ASS_PARAMETER, 
+                      "number of requested bytes missing");
+  nbytes = strtoul (line, NULL, 0);
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (!ctrl->app_ctx)
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+  buffer = xtrymalloc (nbytes);
+  if (!buffer)
+    return out_of_core ();
+
+  rc = app_get_challenge (ctrl->app_ctx, nbytes, buffer);
+  if (!rc)
+    {
+      rc = assuan_send_data (ctx, buffer, nbytes);
+      xfree (buffer);
+      return rc; /* that is already an assuan error code */
+    }
+  xfree (buffer);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+
+static const char hlp_passwd[] =
+  "PASSWD [--reset] [--nullpin] <chvno>\n"
+  "\n"
+  "Change the PIN or, if --reset is given, reset the retry counter of\n"
+  "the card holder verfication vector CHVNO.  The option --nullpin is\n"
+  "used for TCOS cards to set the initial PIN.  The format of CHVNO\n"
+  "depends on the card application.";
+static gpg_error_t
+cmd_passwd (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  char *chvnostr;
+  unsigned int flags = 0;
+
+  if (has_option (line, "--reset"))
+    flags |= APP_CHANGE_FLAG_RESET;
+  if (has_option (line, "--nullpin"))
+    flags |= APP_CHANGE_FLAG_NULLPIN;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  line = skip_options (line);
+
+  if (!*line)
+    return set_error (GPG_ERR_ASS_PARAMETER, "no CHV number given");
+  chvnostr = line;
+  while (*line && !spacep (line))
+    line++;
+  *line = 0;
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (!ctrl->app_ctx)
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+  
+  chvnostr = xtrystrdup (chvnostr);
+  if (!chvnostr)
+    return out_of_core ();
+  rc = app_change_pin (ctrl->app_ctx, ctrl, chvnostr, flags, pin_cb, ctx);
+  if (rc)
+    log_error ("command passwd failed: %s\n", gpg_strerror (rc));
+  xfree (chvnostr);
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_checkpin[] = 
+  "CHECKPIN <idstr>\n"
+  "\n"
+  "Perform a VERIFY operation without doing anything else.  This may\n"
+  "be used to initialize a the PIN cache earlier to long lasting\n"
+  "operations.  Its use is highly application dependent.\n"
+  "\n"
+  "For OpenPGP:\n"
+  "\n"
+  "   Perform a simple verify operation for CHV1 and CHV2, so that\n"
+  "   further operations won't ask for CHV2 and it is possible to do a\n"
+  "   cheap check on the PIN: If there is something wrong with the PIN\n"
+  "   entry system, only the regular CHV will get blocked and not the\n"
+  "   dangerous CHV3.  IDSTR is the usual card's serial number in hex\n"
+  "   notation; an optional fingerprint part will get ignored.  There\n"
+  "   is however a special mode if the IDSTR is sffixed with the\n"
+  "   literal string \"[CHV3]\": In this case the Admin PIN is checked\n"
+  "   if and only if the retry counter is still at 3.\n"
+  "\n"
+  "For Netkey:\n"
+  "\n"
+  "   Any of the valid PIN Ids may be used.  These are the strings:\n"
+  "\n"
+  "     PW1.CH       - Global password 1\n"
+  "     PW2.CH       - Global password 2\n"
+  "     PW1.CH.SIG   - SigG password 1\n"
+  "     PW2.CH.SIG   - SigG password 2\n"
+  "\n"
+  "   For a definitive list, see the implementation in app-nks.c.\n"
+  "   Note that we call a PW2.* PIN a \"PUK\" despite that since TCOS\n"
+  "   3.0 they are technically alternative PINs used to mutally\n"
+  "   unblock each other.";
+static gpg_error_t
+cmd_checkpin (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  char *idstr;
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (!ctrl->app_ctx)
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+  /* We have to use a copy of the key ID because the function may use
+     the pin_cb which in turn uses the assuan line buffer and thus
+     overwriting the original line with the keyid. */
+  idstr = xtrystrdup (line);
+  if (!idstr)
+    return out_of_core ();
+  
+  rc = app_check_pin (ctrl->app_ctx, idstr, pin_cb, ctx);
+  xfree (idstr);
+  if (rc)
+    log_error ("app_check_pin failed: %s\n", gpg_strerror (rc));
+
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_lock[] = 
+  "LOCK [--wait]\n"
+  "\n"
+  "Grant exclusive card access to this session.  Note that there is\n"
+  "no lock counter used and a second lock from the same session will\n"
+  "be ignored.  A single unlock (or RESET) unlocks the session.\n"
+  "Return GPG_ERR_LOCKED if another session has locked the reader.\n"
+  "\n"
+  "If the option --wait is given the command will wait until a\n"
+  "lock has been released.";
+static gpg_error_t
+cmd_lock (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc = 0;
+
+ retry:
+  if (locked_session)
+    {
+      if (locked_session != ctrl->server_local)
+        rc = gpg_error (GPG_ERR_LOCKED);
+    }
+  else
+    locked_session = ctrl->server_local;
+
+#ifdef USE_GNU_PTH
+  if (rc && has_option (line, "--wait"))
+    {
+      rc = 0;
+      pth_sleep (1); /* Better implement an event mechanism. However,
+                        for card operations this should be
+                        sufficient. */
+      /* FIXME: Need to check that the connection is still alive.
+         This can be done by issuing status messages. */
+      goto retry;
+    }
+#endif /*USE_GNU_PTH*/
+  
+  if (rc)
+    log_error ("cmd_lock failed: %s\n", gpg_strerror (rc));
+  return rc;
+}
+
+
+static const char hlp_unlock[] = 
+  "UNLOCK\n"
+  "\n"
+  "Release exclusive card access.";
+static gpg_error_t
+cmd_unlock (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc = 0;
+
+  (void)line;
+
+  if (locked_session)
+    {
+      if (locked_session != ctrl->server_local)
+        rc = gpg_error (GPG_ERR_LOCKED);
+      else
+        locked_session = NULL;
+    }
+  else
+    rc = gpg_error (GPG_ERR_NOT_LOCKED);
+
+  if (rc)
+    log_error ("cmd_unlock failed: %s\n", gpg_strerror (rc));
+  return rc;
+}
+
+
+static const char hlp_getinfo[] = 
+  "GETINFO <what>\n"
+  "\n"
+  "Multi purpose command to return certain information.  \n"
+  "Supported values of WHAT are:\n"
+  "\n"
+  "version     - Return the version of the program.\n"
+  "pid         - Return the process id of the server.\n"
+  "\n"
+  "socket_name - Return the name of the socket.\n"
+  "\n"
+  "status - Return the status of the current slot (in the future, may\n"
+  "also return the status of all slots).  The status is a list of\n"
+  "one-character flags.  The following flags are currently defined:\n"
+  "  'u'  Usable card present.  This is the normal state during operation.\n"
+  "  'r'  Card removed.  A reset is necessary.\n"
+  "These flags are exclusive.\n"
+  "\n"
+  "reader_list - Return a list of detected card readers.  Does\n"
+  "              currently only work with the internal CCID driver.\n"
+  "\n"
+  "deny_admin  - Returns OK if admin commands are not allowed or\n"
+  "              GPG_ERR_GENERAL if admin commands are allowed.\n"
+  "\n"
+  "app_list    - Return a list of supported applications.  One\n"
+  "              application per line, fields delimited by colons,\n"
+  "              first field is the name.";
+static gpg_error_t
+cmd_getinfo (assuan_context_t ctx, char *line)
+{
+  int rc = 0;
+
+  if (!strcmp (line, "version"))
+    {
+      const char *s = VERSION;
+      rc = assuan_send_data (ctx, s, strlen (s));
+    }
+  else if (!strcmp (line, "pid"))
+    {
+      char numbuf[50];
+
+      snprintf (numbuf, sizeof numbuf, "%lu", (unsigned long)getpid ());
+      rc = assuan_send_data (ctx, numbuf, strlen (numbuf));
+    }
+  else if (!strcmp (line, "socket_name"))
+    {
+      const char *s = scd_get_socket_name ();
+
+      if (s)
+        rc = assuan_send_data (ctx, s, strlen (s));
+      else
+        rc = gpg_error (GPG_ERR_NO_DATA);
+    }
+  else if (!strcmp (line, "status"))
+    {
+      ctrl_t ctrl = assuan_get_pointer (ctx);
+      int slot = ctrl->reader_slot;
+      char flag = 'r';
+
+      if (!ctrl->server_local->card_removed && slot != -1)
+	{
+	  struct slot_status_s *ss;
+	  
+	  if (!(slot >= 0 && slot < DIM(slot_table)))
+	    BUG ();
+
+	  ss = &slot_table[slot];
+
+	  if (!ss->valid)
+	    BUG ();
+
+	  if (ss->any && (ss->status & 1))
+	    flag = 'u';
+	}
+      rc = assuan_send_data (ctx, &flag, 1);
+    }
+  else if (!strcmp (line, "reader_list"))
+    {
+#ifdef HAVE_LIBUSB
+      char *s = ccid_get_reader_list ();
+#else
+      char *s = NULL;
+#endif
+      
+      if (s)
+        rc = assuan_send_data (ctx, s, strlen (s));
+      else
+        rc = gpg_error (GPG_ERR_NO_DATA);
+      xfree (s);
+    }
+  else if (!strcmp (line, "deny_admin"))
+    rc = opt.allow_admin? gpg_error (GPG_ERR_GENERAL) : 0;
+  else if (!strcmp (line, "app_list"))
+    {
+      char *s = get_supported_applications ();
+      if (s)
+        rc = assuan_send_data (ctx, s, strlen (s));
+      else
+        rc = 0;
+      xfree (s);
+    }
+  else
+    rc = set_error (GPG_ERR_ASS_PARAMETER, "unknown value for WHAT");
+  return rc;
+}
+
+
+static const char hlp_restart[] = 
+  "RESTART\n"
+  "\n"
+  "Restart the current connection; this is a kind of warm reset.  It\n"
+  "deletes the context used by this connection but does not send a\n"
+  "RESET to the card.  Thus the card itself won't get reset. \n"
+  "\n"
+  "This is used by gpg-agent to reuse a primary pipe connection and\n"
+  "may be used by clients to backup from a conflict in the serial\n"
+  "command; i.e. to select another application.";
+static gpg_error_t
+cmd_restart (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+
+  (void)line;
+
+  if (ctrl->app_ctx)
+    {
+      release_application (ctrl->app_ctx);
+      ctrl->app_ctx = NULL;
+    }
+  if (locked_session && ctrl->server_local == locked_session)
+    {
+      locked_session = NULL;
+      log_info ("implicitly unlocking due to RESTART\n");
+    }
+  return 0;
+}
+
+
+static const char hlp_disconnect[] = 
+  "DISCONNECT\n"
+  "\n"
+  "Disconnect the card if it is not any longer used by other\n"
+  "connections and the backend supports a disconnect operation.";
+static gpg_error_t
+cmd_disconnect (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+
+  (void)line;
+  
+  ctrl->server_local->disconnect_allowed = 1;
+  return 0;
+}
+
+
+
+static const char hlp_apdu[] = 
+  "APDU [--atr] [--more] [--exlen[=N]] [hexstring]\n"
+  "\n"
+  "Send an APDU to the current reader.  This command bypasses the high\n"
+  "level functions and sends the data directly to the card.  HEXSTRING\n"
+  "is expected to be a proper APDU.  If HEXSTRING is not given no\n"
+  "commands are set to the card but the command will implictly check\n"
+  "whether the card is ready for use. \n"
+  "\n"
+  "Using the option \"--atr\" returns the ATR of the card as a status\n"
+  "message before any data like this:\n"
+  "  S CARD-ATR 3BFA1300FF813180450031C173C00100009000B1\n"
+  "\n"
+  "Using the option --more handles the card status word MORE_DATA\n"
+  "(61xx) and concatenates all reponses to one block.\n"
+  "\n"
+  "Using the option \"--exlen\" the returned APDU may use extended\n"
+  "length up to N bytes.  If N is not given a default value is used\n"
+  "(currently 4096).";
+static gpg_error_t
+cmd_apdu (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+  int rc;
+  unsigned char *apdu;
+  size_t apdulen;
+  int with_atr;
+  int handle_more;
+  const char *s;
+  size_t exlen;
+
+  with_atr = has_option (line, "--atr");
+  handle_more = has_option (line, "--more");
+
+  if ((s=has_option_name (line, "--exlen")))
+    {
+      if (*s == '=')
+        exlen = strtoul (s+1, NULL, 0);
+      else
+        exlen = 4096;
+    }
+  else
+    exlen = 0;
+
+  line = skip_options (line);
+
+  if ( IS_LOCKED (ctrl) )
+    return gpg_error (GPG_ERR_LOCKED);
+
+  if ((rc = open_card (ctrl, NULL)))
+    return rc;
+
+  if (with_atr)
+    {
+      unsigned char *atr;
+      size_t atrlen;
+      char hexbuf[400];
+      
+      atr = apdu_get_atr (ctrl->reader_slot, &atrlen);
+      if (!atr || atrlen > sizeof hexbuf - 2 )
+        {
+          rc = gpg_error (GPG_ERR_INV_CARD);
+          goto leave;
+        }
+      bin2hex (atr, atrlen, hexbuf);
+      xfree (atr);
+      send_status_info (ctrl, "CARD-ATR", hexbuf, strlen (hexbuf), NULL, 0);
+    }
+
+  apdu = hex_to_buffer (line, &apdulen);
+  if (!apdu)
+    {
+      rc = gpg_error_from_syserror ();
+      goto leave;
+    }
+  if (apdulen)
+    {
+      unsigned char *result = NULL;
+      size_t resultlen;
+
+      rc = apdu_send_direct (ctrl->reader_slot, exlen,
+                             apdu, apdulen, handle_more,
+                             &result, &resultlen);
+      if (rc)
+        log_error ("apdu_send_direct failed: %s\n", gpg_strerror (rc));
+      else
+        {
+          rc = assuan_send_data (ctx, result, resultlen);
+          xfree (result);
+        }
+    }
+  xfree (apdu);
+
+ leave:
+  TEST_CARD_REMOVAL (ctrl, rc);
+  return rc;
+}
+
+
+static const char hlp_killscd[] = 
+  "KILLSCD\n"
+  "\n"
+  "Commit suicide.";
+static gpg_error_t
+cmd_killscd (assuan_context_t ctx, char *line)
+{
+  ctrl_t ctrl = assuan_get_pointer (ctx);
+
+  (void)line;
+
+  ctrl->server_local->stopme = 1;
+  return gpg_error (GPG_ERR_EOF);
+}
+
+
+
+/* Tell the assuan library about our commands */
+static int
+register_commands (assuan_context_t ctx)
+{
+  static struct {
+    const char *name;
+    assuan_handler_t handler;
+    const char * const help;
+  } table[] = {
+    { "SERIALNO",     cmd_serialno, hlp_serialno },
+    { "LEARN",        cmd_learn,    hlp_learn },
+    { "READCERT",     cmd_readcert, hlp_readcert },
+    { "READKEY",      cmd_readkey,  hlp_readkey },
+    { "SETDATA",      cmd_setdata,  hlp_setdata },
+    { "PKSIGN",       cmd_pksign,   hlp_pksign },
+    { "PKAUTH",       cmd_pkauth,   hlp_pkauth },
+    { "PKDECRYPT",    cmd_pkdecrypt,hlp_pkdecrypt },
+    { "INPUT",        NULL }, 
+    { "OUTPUT",       NULL }, 
+    { "GETATTR",      cmd_getattr,  hlp_getattr },
+    { "SETATTR",      cmd_setattr,  hlp_setattr },
+    { "WRITECERT",    cmd_writecert,hlp_writecert },
+    { "WRITEKEY",     cmd_writekey, hlp_writekey },
+    { "GENKEY",       cmd_genkey,   hlp_genkey },
+    { "RANDOM",       cmd_random,   hlp_random },
+    { "PASSWD",       cmd_passwd,   hlp_passwd },
+    { "CHECKPIN",     cmd_checkpin, hlp_checkpin },
+    { "LOCK",         cmd_lock,     hlp_lock },
+    { "UNLOCK",       cmd_unlock,   hlp_unlock },
+    { "GETINFO",      cmd_getinfo,  hlp_getinfo },
+    { "RESTART",      cmd_restart,  hlp_restart },
+    { "DISCONNECT",   cmd_disconnect,hlp_disconnect },
+    { "APDU",         cmd_apdu,     hlp_apdu },
+    { "KILLSCD",      cmd_killscd,  hlp_killscd },
+    { NULL }
+  };
+  int i, rc;
+
+  for (i=0; table[i].name; i++)
+    {
+      rc = assuan_register_command (ctx, table[i].name, table[i].handler,
+                                    table[i].help);
+      if (rc)
+        return rc;
+    } 
+  assuan_set_hello_line (ctx, "GNU Privacy Guard's Smartcard server ready");
+
+  assuan_register_reset_notify (ctx, reset_notify);
+  assuan_register_option_handler (ctx, option_handler);
+  return 0;
+}
+
+
+/* Startup the server.  If FD is given as -1 this is simple pipe
+   server, otherwise it is a regular server.  Returns true if there
+   are no more active asessions.  */
+int
+scd_command_handler (ctrl_t ctrl, int fd)
+{
+  int rc;
+  assuan_context_t ctx = NULL;
+  int stopme;
+  
+  rc = assuan_new (&ctx);
+  if (rc)
+    {
+      log_error ("failed to allocate assuan context: %s\n",
+                 gpg_strerror (rc));
+      scd_exit (2);
+    }
+
+  if (fd == -1)
+    {
+      assuan_fd_t filedes[2];
+
+      filedes[0] = assuan_fdopen (0);
+      filedes[1] = assuan_fdopen (1);
+      rc = assuan_init_pipe_server (ctx, filedes);
+    }
+  else
+    {
+      rc = assuan_init_socket_server (ctx, INT2FD(fd),
+				      ASSUAN_SOCKET_SERVER_ACCEPTED);
+    }
+  if (rc)
+    {
+      log_error ("failed to initialize the server: %s\n",
+                 gpg_strerror(rc));
+      scd_exit (2);
+    }
+  rc = register_commands (ctx);
+  if (rc)
+    {
+      log_error ("failed to register commands with Assuan: %s\n",
+                 gpg_strerror(rc));
+      scd_exit (2);
+    }
+  assuan_set_pointer (ctx, ctrl);
+
+  /* Allocate and initialize the server object.  Put it into the list
+     of active sessions. */
+  ctrl->server_local = xcalloc (1, sizeof *ctrl->server_local);
+  ctrl->server_local->next_session = session_list;
+  session_list = ctrl->server_local;
+  ctrl->server_local->ctrl_backlink = ctrl;
+  ctrl->server_local->assuan_ctx = ctx;
+
+  if (DBG_ASSUAN)
+    assuan_set_log_stream (ctx, log_get_stream ());
+
+  /* We open the reader right at startup so that the ticker is able to
+     update the status file. */
+  if (ctrl->reader_slot == -1)
+    {
+      ctrl->reader_slot = get_reader_slot ();
+    }
+
+  /* Command processing loop. */
+  for (;;)
+    {
+      rc = assuan_accept (ctx);
+      if (rc == -1)
+        {
+          break;
+        }
+      else if (rc)
+        {
+          log_info ("Assuan accept problem: %s\n", gpg_strerror (rc));
+          break;
+        }
+      
+      rc = assuan_process (ctx);
+      if (rc)
+        {
+          log_info ("Assuan processing failed: %s\n", gpg_strerror (rc));
+          continue;
+        }
+    }
+
+  /* Cleanup.  We don't send an explicit reset to the card.  */
+  do_reset (ctrl, 0); 
+
+  /* Release the server object.  */
+  if (session_list == ctrl->server_local)
+    session_list = ctrl->server_local->next_session;
+  else
+    {
+      struct server_local_s *sl;
+      
+      for (sl=session_list; sl->next_session; sl = sl->next_session)
+        if (sl->next_session == ctrl->server_local)
+          break;
+      if (!sl->next_session)
+          BUG ();
+      sl->next_session = ctrl->server_local->next_session;
+    }
+  stopme = ctrl->server_local->stopme || reader_disabled;
+  xfree (ctrl->server_local);
+  ctrl->server_local = NULL;
+
+  /* Release the Assuan context.  */
+  assuan_release (ctx);
+
+  if (stopme)
+    scd_exit (0);
+
+  /* If there are no more sessions return true.  */
+  return !session_list;
+}
+
+
+/* Send a line with status information via assuan and escape all given
+   buffers. The variable elements are pairs of (char *, size_t),
+   terminated with a (NULL, 0). */
+void
+send_status_info (ctrl_t ctrl, const char *keyword, ...)
+{
+  va_list arg_ptr;
+  const unsigned char *value;
+  size_t valuelen;
+  char buf[950], *p;
+  size_t n;
+  assuan_context_t ctx = ctrl->server_local->assuan_ctx;
+  
+  va_start (arg_ptr, keyword);
+
+  p = buf; 
+  n = 0;
+  while ( (value = va_arg (arg_ptr, const unsigned char *)) )
+    {
+      valuelen = va_arg (arg_ptr, size_t);
+      if (!valuelen)
+        continue; /* empty buffer */
+      if (n)
+        {
+          *p++ = ' ';
+          n++;
+        }
+      for ( ; valuelen && n < DIM (buf)-2; n++, valuelen--, value++)
+        {
+          if (*value < ' ' || *value == '+')
+            {
+              sprintf (p, "%%%02X", *value);
+              p += 3;
+            }
+          else if (*value == ' ')
+            *p++ = '+';
+          else
+            *p++ = *value;
+        }
+    }
+  *p = 0;
+  assuan_write_status (ctx, keyword, buf);
+
+  va_end (arg_ptr);
+}
+
+
+/* Send a ready formatted status line via assuan.  */
+void
+send_status_direct (ctrl_t ctrl, const char *keyword, const char *args)
+{
+  assuan_context_t ctx = ctrl->server_local->assuan_ctx;
+
+  if (strchr (args, '\n'))
+    log_error ("error: LF detected in status line - not sending\n");
+  else
+    assuan_write_status (ctx, keyword, args);
+}
+
+
+/* Helper to send the clients a status change notification.  */
+static void
+send_client_notifications (void)
+{
+  struct {
+    pid_t pid; 
+#ifdef HAVE_W32_SYSTEM
+    HANDLE handle;
+#else
+    int signo; 
+#endif
+  } killed[50];
+  int killidx = 0;
+  int kidx;
+  struct server_local_s *sl;
+  
+  for (sl=session_list; sl; sl = sl->next_session)
+    {
+      if (sl->event_signal && sl->assuan_ctx)
+        {
+          pid_t pid = assuan_get_pid (sl->assuan_ctx);
+#ifdef HAVE_W32_SYSTEM
+          HANDLE handle = (void *)sl->event_signal;
+          
+          for (kidx=0; kidx < killidx; kidx++)
+            if (killed[kidx].pid == pid 
+                && killed[kidx].handle == handle)
+              break;
+          if (kidx < killidx)
+            log_info ("event %lx (%p) already triggered for client %d\n",
+                      sl->event_signal, handle, (int)pid);
+          else
+            {
+              log_info ("triggering event %lx (%p) for client %d\n",
+                        sl->event_signal, handle, (int)pid);
+              if (!SetEvent (handle))
+                log_error ("SetEvent(%lx) failed: %s\n",
+                           sl->event_signal, w32_strerror (-1));
+              if (killidx < DIM (killed))
+                {
+                  killed[killidx].pid = pid;
+                  killed[killidx].handle = handle;
+                  killidx++;
+                }
+            }
+#else /*!HAVE_W32_SYSTEM*/
+          int signo = sl->event_signal;
+          
+          if (pid != (pid_t)(-1) && pid && signo > 0)
+            {
+              for (kidx=0; kidx < killidx; kidx++)
+                if (killed[kidx].pid == pid 
+                    && killed[kidx].signo == signo)
+                  break;
+              if (kidx < killidx)
+                log_info ("signal %d already sent to client %d\n",
+                          signo, (int)pid);
+              else
+                {
+                  log_info ("sending signal %d to client %d\n",
+                            signo, (int)pid);
+                  kill (pid, signo);
+                  if (killidx < DIM (killed))
+                    {
+                      killed[killidx].pid = pid;
+                      killed[killidx].signo = signo;
+                      killidx++;
+                    }
+                }
+            }
+#endif /*!HAVE_W32_SYSTEM*/
+        }
+    }
+}
+
+
+
+/* This is the core of scd_update_reader_status_file but the caller
+   needs to take care of the locking.  */
+static void
+update_reader_status_file (int set_card_removed_flag)
+{
+  int idx;
+  unsigned int status, changed;
+
+  /* Make sure that the reader has been opened.  Like get_reader_slot,
+     this part of the code assumes that there is only one reader.  */
+  if (!slot_table[0].valid)
+    (void)get_reader_slot ();
+
+  /* Note, that we only try to get the status, because it does not
+     make sense to wait here for a operation to complete.  If we are
+     busy working with a card, delays in the status file update should
+     be acceptable. */
+  for (idx=0; idx < DIM(slot_table); idx++)
+    {
+      struct slot_status_s *ss = slot_table + idx;
+      struct server_local_s *sl;
+      int sw_apdu;
+
+      if (!ss->valid || ss->slot == -1)
+        continue; /* Not valid or reader not yet open. */
+      
+      sw_apdu = apdu_get_status (ss->slot, 0, &status, &changed);
+      if (sw_apdu == SW_HOST_NO_READER)
+        {
+          /* Most likely the _reader_ has been unplugged.  */
+	  apdu_close_reader (ss->slot);
+	  ss->valid = 0;
+          status = 0;
+          changed = ss->changed;
+        }
+      else if (sw_apdu)
+        {
+          /* Get status failed.  Ignore that.  */
+          continue; 
+        }
+
+      if (!ss->any || ss->status != status || ss->changed != changed )
+        {
+          char *fname;
+          char templ[50];
+          FILE *fp;
+
+          log_info ("updating slot %d status: 0x%04X->0x%04X (%u->%u)\n",
+                    ss->slot, ss->status, status, ss->changed, changed);
+          ss->status = status;
+          ss->changed = changed;
+
+	  /* FIXME: Should this be IDX instead of ss->slot?  This
+	     depends on how client sessions will associate the reader
+	     status with their session.  */
+          snprintf (templ, sizeof templ, "reader_%d.status", ss->slot);
+          fname = make_filename (opt.homedir, templ, NULL );
+          fp = fopen (fname, "w");
+          if (fp)
+            {
+              fprintf (fp, "%s\n",
+                       (status & 1)? "USABLE":
+                       (status & 4)? "ACTIVE":
+                       (status & 2)? "PRESENT": "NOCARD");
+              fclose (fp);
+            }
+          xfree (fname);
+            
+          /* If a status script is executable, run it. */
+          {
+            const char *args[9], *envs[2];
+            char numbuf1[30], numbuf2[30], numbuf3[30];
+            char *homestr, *envstr;
+            gpg_error_t err;
+            
+            homestr = make_filename (opt.homedir, NULL);
+            if (estream_asprintf (&envstr, "GNUPGHOME=%s", homestr) < 0)
+              log_error ("out of core while building environment\n");
+            else
+              {
+                envs[0] = envstr;
+                envs[1] = NULL;
+
+                sprintf (numbuf1, "%d", ss->slot);
+                sprintf (numbuf2, "0x%04X", ss->status);
+                sprintf (numbuf3, "0x%04X", status);
+                args[0] = "--reader-port";
+                args[1] = numbuf1; 
+                args[2] = "--old-code";
+                args[3] = numbuf2;  
+                args[4] = "--new-code";
+                args[5] = numbuf3; 
+                args[6] = "--status";
+                args[7] = ((status & 1)? "USABLE":
+                           (status & 4)? "ACTIVE":
+                           (status & 2)? "PRESENT": "NOCARD");
+                args[8] = NULL;  
+
+                fname = make_filename (opt.homedir, "scd-event", NULL);
+                err = gnupg_spawn_process_detached (fname, args, envs);
+                if (err && gpg_err_code (err) != GPG_ERR_ENOENT)
+                  log_error ("failed to run event handler `%s': %s\n",
+                             fname, gpg_strerror (err));
+                xfree (fname);
+                xfree (envstr);
+              }
+            xfree (homestr);
+          }
+
+          /* Set the card removed flag for all current sessions.  We
+             will set this on any card change because a reset or
+             SERIALNO request must be done in any case.  */
+          if (ss->any && set_card_removed_flag)
+            update_card_removed (idx, 1);
+          
+          ss->any = 1;
+
+          /* Send a signal to all clients who applied for it.  */
+          send_client_notifications ();
+        }
+      
+      /* Check whether a disconnect is pending.  */
+      if (opt.card_timeout)
+        {
+          for (sl=session_list; sl; sl = sl->next_session)
+            if (!sl->disconnect_allowed)
+              break; 
+          if (session_list && !sl)
+            {
+              /* FIXME: Use a real timeout.  */
+              /* At least one connection and all allow a disconnect.  */
+              log_info ("disconnecting card in slot %d\n", ss->slot);
+              apdu_disconnect (ss->slot);
+            }
+        }
+      
+    }
+}
+
+/* This function is called by the ticker thread to check for changes
+   of the reader stati.  It updates the reader status files and if
+   requested by the caller also send a signal to the caller.  */
+void
+scd_update_reader_status_file (void)
+{
+  if (!pth_mutex_acquire (&status_file_update_lock, 1, NULL))
+    return; /* locked - give up. */
+  update_reader_status_file (1);
+  if (!pth_mutex_release (&status_file_update_lock))
+    log_error ("failed to release status_file_update lock\n");
+}