Adding upstream version 2.2.40.upstream/2.2.40upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1428 insertions, 0 deletions

diff --git a/scd/app-nks.c b/scd/app-nks.c
new file mode 100644
index 0000000..1f59321
--- /dev/null
+++ b/scd/app-nks.c
@@ -0,0 +1,1428 @@
+/* app-nks.c - The Telesec NKS card application.
+ * Copyright (C) 2004, 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 <https://www.gnu.org/licenses/>.
+ */
+
+/* Notes:
+
+  - We are now targeting TCOS 3 cards and it may happen that there is
+    a regression towards TCOS 2 cards.  Please report.
+
+  - The TKS3 AUT key is not used.  It seems that it is only useful for
+    the internal authentication command and not accessible by other
+    applications.  The key itself is in the encryption class but the
+    corresponding certificate has only the digitalSignature
+    capability.
+
+  - If required, we automagically switch between the NKS application
+    and the SigG application.  This avoids to use the DINSIG
+    application which is somewhat limited, has no support for Secure
+    Messaging as required by TCOS 3 and has no way to change the PIN
+    or even set the NullPIN.
+
+  - We use the prefix NKS-DF01 for TCOS 2 cards and NKS-NKS3 for newer
+    cards.  This is because the NKS application has moved to DF02 with
+    TCOS 3 and thus we better use a DF independent tag.
+
+  - We use only the global PINs for the NKS application.
+
+ */
+
+#include <config.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <time.h>
+
+#include "scdaemon.h"
+#include "../common/i18n.h"
+#include "iso7816.h"
+#include "../common/tlv.h"
+#include "apdu.h"
+#include "../common/host2net.h"
+
+static char const aid_nks[]  = { 0xD2, 0x76, 0x00, 0x00, 0x03, 0x01, 0x02 };
+static char const aid_sigg[] = { 0xD2, 0x76, 0x00, 0x00, 0x66, 0x01 };
+
+
+static struct
+{
+  int is_sigg;   /* Valid for SigG application.  */
+  int fid;       /* File ID. */
+  int nks_ver;   /* 0 for NKS version 2, 3 for version 3. */
+  int certtype;  /* Type of certificate or 0 if it is not a certificate. */
+  int iskeypair; /* If true has the FID of the corresponding certificate. */
+  int issignkey; /* True if file is a key usable for signing. */
+  int isenckey;  /* True if file is a key usable for decryption. */
+  unsigned char kid;  /* Corresponding key references.  */
+} filelist[] = {
+  { 0, 0x4531, 0, 0,  0xC000, 1, 0, 0x80 }, /* EF_PK.NKS.SIG */
+  { 0, 0xC000, 0, 101 },                    /* EF_C.NKS.SIG  */
+  { 0, 0x4331, 0, 100 },
+  { 0, 0x4332, 0, 100 },
+  { 0, 0xB000, 0, 110 },                    /* EF_PK.RCA.NKS */
+  { 0, 0x45B1, 0, 0,  0xC200, 0, 1, 0x81 }, /* EF_PK.NKS.ENC */
+  { 0, 0xC200, 0, 101 },                    /* EF_C.NKS.ENC  */
+  { 0, 0x43B1, 0, 100 },
+  { 0, 0x43B2, 0, 100 },
+/* The authentication key is not used.  */
+/*   { 0, 0x4571, 3, 0,  0xC500, 0, 0, 0x82 }, /\* EF_PK.NKS.AUT *\/ */
+/*   { 0, 0xC500, 3, 101 },                    /\* EF_C.NKS.AUT  *\/ */
+  { 0, 0x45B2, 3, 0,  0xC201, 0, 1, 0x83 }, /* EF_PK.NKS.ENC1024 */
+  { 0, 0xC201, 3, 101 },                    /* EF_C.NKS.ENC1024  */
+  { 1, 0x4531, 3, 0,  0xC000, 1, 1, 0x84 }, /* EF_PK.CH.SIG  */
+  { 1, 0xC000, 0, 101 },                    /* EF_C.CH.SIG  */
+  { 1, 0xC008, 3, 101 },                    /* EF_C.CA.SIG  */
+  { 1, 0xC00E, 3, 111 },                    /* EF_C.RCA.SIG  */
+  { 0, 0 }
+};
+
+
+
+/* Object with application (i.e. NKS) specific data.  */
+struct app_local_s {
+  int nks_version;  /* NKS version.  */
+
+  int sigg_active;  /* True if switched to the SigG application.  */
+  int sigg_msig_checked;/*  True if we checked for a mass signature card.  */
+  int sigg_is_msig; /* True if this is a mass signature card.  */
+
+  int need_app_select; /* Need to re-select the application.  */
+
+};
+
+
+
+static gpg_error_t switch_application (app_t app, int enable_sigg);
+
+
+
+/* Release local data. */
+static void
+do_deinit (app_t app)
+{
+  if (app && app->app_local)
+    {
+      xfree (app->app_local);
+      app->app_local = NULL;
+    }
+}
+
+
+static int
+all_zero_p (void *buffer, size_t length)
+{
+  char *p;
+
+  for (p=buffer; length; length--, p++)
+    if (*p)
+      return 0;
+  return 1;
+}
+
+
+/* Read the file with FID, assume it contains a public key and return
+   its keygrip in the caller provided 41 byte buffer R_GRIPSTR. */
+static gpg_error_t
+keygripstr_from_pk_file (app_t app, int fid, char *r_gripstr)
+{
+  gpg_error_t err;
+  unsigned char grip[20];
+  unsigned char *buffer[2];
+  size_t buflen[2];
+  gcry_sexp_t sexp;
+  int i;
+  int offset[2] = { 0, 0 };
+
+  err = iso7816_select_file (app->slot, fid, 0);
+  if (err)
+    return err;
+  err = iso7816_read_record (app->slot, 1, 1, 0, &buffer[0], &buflen[0]);
+  if (err)
+    return err;
+  err = iso7816_read_record (app->slot, 2, 1, 0, &buffer[1], &buflen[1]);
+  if (err)
+    {
+      xfree (buffer[0]);
+      return err;
+    }
+
+  if (app->app_local->nks_version < 3)
+    {
+      /* Old versions of NKS store the values in a TLV encoded format.
+         We need to do some checks.  */
+      for (i=0; i < 2; i++)
+        {
+          /* Check that the value appears like an integer encoded as
+             Simple-TLV.  We don't check the tag because the tests cards I
+             have use 1 for both, the modulus and the exponent - the
+             example in the documentation gives 2 for the exponent. */
+          if (buflen[i] < 3)
+            err = gpg_error (GPG_ERR_TOO_SHORT);
+          else if (buffer[i][1] != buflen[i]-2 )
+            err = gpg_error (GPG_ERR_INV_OBJ);
+          else
+            offset[i] = 2;
+        }
+    }
+  else
+    {
+      /* Remove leading zeroes to get a correct keygrip.  Take care of
+         negative numbers.  We should also fix it the same way in
+         libgcrypt but we can't yet rely on it yet.  */
+      for (i=0; i < 2; i++)
+        {
+          while (buflen[i]-offset[i] > 1
+                 && !buffer[i][offset[i]]
+                 && !(buffer[i][offset[i]+1] & 0x80))
+            offset[i]++;
+        }
+    }
+
+  /* Check whether negative values are not prefixed with a zero and
+     fix that.  */
+  for (i=0; i < 2; i++)
+    {
+      if ((buflen[i]-offset[i]) && (buffer[i][offset[i]] & 0x80))
+        {
+          unsigned char *newbuf;
+          size_t newlen;
+
+          newlen = 1 + buflen[i] - offset[i];
+          newbuf = xtrymalloc (newlen);
+          if (!newbuf)
+            {
+              xfree (buffer[0]);
+              xfree (buffer[1]);
+              return gpg_error_from_syserror ();
+            }
+          newbuf[0] = 0;
+          memcpy (newbuf+1, buffer[i]+offset[i], buflen[i] - offset[i]);
+          xfree (buffer[i]);
+          buffer[i] = newbuf;
+          buflen[i] = newlen;
+          offset[i] = 0;
+        }
+    }
+
+  if (!err)
+    err = gcry_sexp_build (&sexp, NULL,
+                           "(public-key (rsa (n %b) (e %b)))",
+                           (int)buflen[0]-offset[0], buffer[0]+offset[0],
+                           (int)buflen[1]-offset[1], buffer[1]+offset[1]);
+
+  xfree (buffer[0]);
+  xfree (buffer[1]);
+  if (err)
+    return err;
+
+  if (!gcry_pk_get_keygrip (sexp, grip))
+    {
+      err = gpg_error (GPG_ERR_INTERNAL); /* i.e. RSA not supported by
+                                             libgcrypt. */
+    }
+  else
+    {
+      bin2hex (grip, 20, r_gripstr);
+    }
+  gcry_sexp_release (sexp);
+  return err;
+}
+
+
+/* TCOS responds to a verify with empty data (i.e. without the Lc
+ * byte) with the status of the PIN.  PWID is the PIN ID, If SIGG is
+ * true, the application is switched into SigG mode.  Returns:
+ * ISO7816_VERIFY_* codes or non-negative number of verification
+ * attempts left.  */
+static int
+get_chv_status (app_t app, int sigg, int pwid)
+{
+  if (switch_application (app, sigg))
+    return sigg? -2 : -1; /* No such PIN / General error.  */
+
+  return iso7816_verify_status (app_get_slot (app), pwid);
+}
+
+
+/* Implement the GETATTR command.  This is similar to the LEARN
+   command but returns just one value via the status interface. */
+static gpg_error_t
+do_getattr (app_t app, ctrl_t ctrl, const char *name)
+{
+  static struct {
+    const char *name;
+    int special;
+  } table[] = {
+    { "$AUTHKEYID",   1 },
+    { "$ENCRKEYID",   2 },
+    { "$SIGNKEYID",   3 },
+    { "NKS-VERSION",  4 },
+    { "CHV-STATUS",   5 },
+    { NULL, 0 }
+  };
+  gpg_error_t err = 0;
+  int idx;
+  char buffer[100];
+
+  err = switch_application (app, 0);
+  if (err)
+    return err;
+
+  for (idx=0; table[idx].name && strcmp (table[idx].name, name); idx++)
+    ;
+  if (!table[idx].name)
+    return gpg_error (GPG_ERR_INV_NAME);
+
+  switch (table[idx].special)
+    {
+    case 1: /* $AUTHKEYID */
+      {
+        /* NetKey 3.0 cards define an authentication key but according
+           to the specs this key is only usable for encryption and not
+           signing.  it might work anyway but it has not yet been
+           tested - fixme.  Thus for now we use the NKS signature key
+           for authentication.  */
+        char const tmp[] = "NKS-NKS3.4531";
+        send_status_info (ctrl, table[idx].name, tmp, strlen (tmp), NULL, 0);
+      }
+      break;
+
+    case 2: /* $ENCRKEYID */
+      {
+        char const tmp[] = "NKS-NKS3.45B1";
+        send_status_info (ctrl, table[idx].name, tmp, strlen (tmp), NULL, 0);
+      }
+      break;
+
+    case 3: /* $SIGNKEYID */
+      {
+        char const tmp[] = "NKS-NKS3.4531";
+        send_status_info (ctrl, table[idx].name, tmp, strlen (tmp), NULL, 0);
+      }
+      break;
+
+    case 4: /* NKS-VERSION */
+      snprintf (buffer, sizeof buffer, "%d", app->app_local->nks_version);
+      send_status_info (ctrl, table[idx].name,
+                        buffer, strlen (buffer), NULL, 0);
+      break;
+
+    case 5: /* CHV-STATUS */
+      {
+        /* Returns: PW1.CH PW2.CH PW1.CH.SIG PW2.CH.SIG That are the
+           two global passwords followed by the two SigG passwords.
+           For the values, see the function get_chv_status.  */
+        int tmp[4];
+
+        /* We use a helper array so that we can control that there is
+           no superfluous application switch.  Note that PW2.CH.SIG
+           really has the identifier 0x83 and not 0x82 as one would
+           expect.  */
+        tmp[0] = get_chv_status (app, 0, 0x00);
+        tmp[1] = get_chv_status (app, 0, 0x01);
+        tmp[2] = get_chv_status (app, 1, 0x81);
+        tmp[3] = get_chv_status (app, 1, 0x83);
+        snprintf (buffer, sizeof buffer,
+                  "%d %d %d %d", tmp[0], tmp[1], tmp[2], tmp[3]);
+        send_status_info (ctrl, table[idx].name,
+                          buffer, strlen (buffer), NULL, 0);
+      }
+      break;
+
+
+    default:
+      err = gpg_error (GPG_ERR_NOT_IMPLEMENTED);
+      break;
+    }
+
+  return err;
+}
+
+
+
+static void
+do_learn_status_core (app_t app, ctrl_t ctrl, unsigned int flags, int is_sigg)
+{
+  gpg_error_t err;
+  char ct_buf[100], id_buf[100];
+  int i;
+  const char *tag;
+  const char *usage;
+
+  if (is_sigg)
+    tag = "SIGG";
+  else if (app->app_local->nks_version < 3)
+    tag = "DF01";
+  else
+    tag = "NKS3";
+
+  /* Output information about all useful objects in the NKS application. */
+  for (i=0; filelist[i].fid; i++)
+    {
+      if (filelist[i].nks_ver > app->app_local->nks_version)
+        continue;
+
+      if (!!filelist[i].is_sigg != !!is_sigg)
+        continue;
+
+      if (filelist[i].certtype && !(flags &1))
+        {
+          size_t len;
+
+          len = app_help_read_length_of_cert (app->slot,
+                                              filelist[i].fid, NULL);
+          if (len)
+            {
+              /* FIXME: We should store the length in the application's
+                 context so that a following readcert does only need to
+                 read that many bytes. */
+              snprintf (ct_buf, sizeof ct_buf, "%d", filelist[i].certtype);
+              snprintf (id_buf, sizeof id_buf, "NKS-%s.%04X",
+                        tag, filelist[i].fid);
+              send_status_info (ctrl, "CERTINFO",
+                                ct_buf, strlen (ct_buf),
+                                id_buf, strlen (id_buf),
+                                NULL, (size_t)0);
+            }
+        }
+      else if (filelist[i].iskeypair)
+        {
+          char gripstr[40+1];
+
+          err = keygripstr_from_pk_file (app, filelist[i].fid, gripstr);
+          if (err)
+            log_error ("can't get keygrip from FID 0x%04X: %s\n",
+                       filelist[i].fid, gpg_strerror (err));
+          else
+            {
+              snprintf (id_buf, sizeof id_buf, "NKS-%s.%04X",
+                        tag, filelist[i].fid);
+              if (filelist[i].issignkey && filelist[i].isenckey)
+                usage = "sae";
+              else if (filelist[i].issignkey)
+                usage = "sa";
+              else if (filelist[i].isenckey)
+                usage = "e";
+              else
+                usage = "";
+
+              send_status_info (ctrl, "KEYPAIRINFO",
+                                gripstr, 40,
+                                id_buf, strlen (id_buf),
+                                usage, strlen (usage),
+                                NULL, (size_t)0);
+            }
+        }
+    }
+
+
+}
+
+
+static gpg_error_t
+do_learn_status (app_t app, ctrl_t ctrl, unsigned int flags)
+{
+  gpg_error_t err;
+
+  err = switch_application (app, 0);
+  if (err)
+    return err;
+
+  do_learn_status_core (app, ctrl, flags, 0);
+
+  err = switch_application (app, 1);
+  if (err)
+    return 0;  /* Silently ignore if we can't switch to SigG.  */
+
+  do_learn_status_core (app, ctrl, flags, 1);
+
+  return 0;
+}
+
+
+
+
+/* Read the certificate with id CERTID (as returned by learn_status in
+   the CERTINFO status lines) and return it in the freshly allocated
+   buffer put into CERT and the length of the certificate put into
+   CERTLEN. */
+static gpg_error_t
+do_readcert (app_t app, const char *certid,
+             unsigned char **cert, size_t *certlen)
+{
+  int i, fid;
+  gpg_error_t err;
+  unsigned char *buffer;
+  const unsigned char *p;
+  size_t buflen, n;
+  int class, tag, constructed, ndef;
+  size_t totobjlen, objlen, hdrlen;
+  int rootca = 0;
+  int is_sigg = 0;
+
+  *cert = NULL;
+  *certlen = 0;
+
+  if (!strncmp (certid, "NKS-NKS3.", 9))
+    ;
+  else if (!strncmp (certid, "NKS-DF01.", 9))
+    ;
+  else if (!strncmp (certid, "NKS-SIGG.", 9))
+    is_sigg = 1;
+  else
+    return gpg_error (GPG_ERR_INV_ID);
+
+  err = switch_application (app, is_sigg);
+  if (err)
+    return err;
+
+  certid += 9;
+  if (!hexdigitp (certid) || !hexdigitp (certid+1)
+      || !hexdigitp (certid+2) || !hexdigitp (certid+3)
+      || certid[4])
+    return gpg_error (GPG_ERR_INV_ID);
+  fid = xtoi_4 (certid);
+  for (i=0; filelist[i].fid; i++)
+    if ((filelist[i].certtype || filelist[i].iskeypair)
+        && filelist[i].fid == fid)
+      break;
+  if (!filelist[i].fid)
+    return gpg_error (GPG_ERR_NOT_FOUND);
+
+  /* If the requested objects is a plain public key, redirect it to
+     the corresponding certificate.  The whole system is a bit messy
+     because we sometime use the key directly or let the caller
+     retrieve the key from the certificate.  The rationale for
+     that is to support not-yet stored certificates. */
+  if (filelist[i].iskeypair)
+    fid = filelist[i].iskeypair;
+
+
+  /* Read the entire file.  fixme: This could be optimized by first
+     reading the header to figure out how long the certificate
+     actually is. */
+  err = iso7816_select_file (app->slot, fid, 0);
+  if (err)
+    {
+      log_error ("error selecting FID 0x%04X: %s\n", fid, gpg_strerror (err));
+      return err;
+    }
+
+  err = iso7816_read_binary (app->slot, 0, 0, &buffer, &buflen);
+  if (err)
+    {
+      log_error ("error reading certificate from FID 0x%04X: %s\n",
+                 fid, gpg_strerror (err));
+      return err;
+    }
+
+  if (!buflen || *buffer == 0xff)
+    {
+      log_info ("no certificate contained in FID 0x%04X\n", fid);
+      err = gpg_error (GPG_ERR_NOT_FOUND);
+      goto leave;
+    }
+
+  /* Now figure something out about the object. */
+  p = buffer;
+  n = buflen;
+  err = parse_ber_header (&p, &n, &class, &tag, &constructed,
+                          &ndef, &objlen, &hdrlen);
+  if (err)
+    goto leave;
+  if ( class == CLASS_UNIVERSAL && tag == TAG_SEQUENCE && constructed )
+    ;
+  else if ( class == CLASS_UNIVERSAL && tag == TAG_SET && constructed )
+    rootca = 1;
+  else
+    return gpg_error (GPG_ERR_INV_OBJ);
+  totobjlen = objlen + hdrlen;
+  assert (totobjlen <= buflen);
+
+  err = parse_ber_header (&p, &n, &class, &tag, &constructed,
+                          &ndef, &objlen, &hdrlen);
+  if (err)
+    goto leave;
+
+  if (rootca)
+    ;
+  else if (class == CLASS_UNIVERSAL && tag == TAG_OBJECT_ID && !constructed)
+    {
+      const unsigned char *save_p;
+
+      /* The certificate seems to be contained in a userCertificate
+         container.  Skip this and assume the following sequence is
+         the certificate. */
+      if (n < objlen)
+        {
+          err = gpg_error (GPG_ERR_INV_OBJ);
+          goto leave;
+        }
+      p += objlen;
+      n -= objlen;
+      save_p = p;
+      err = parse_ber_header (&p, &n, &class, &tag, &constructed,
+                              &ndef, &objlen, &hdrlen);
+      if (err)
+        goto leave;
+      if ( !(class == CLASS_UNIVERSAL && tag == TAG_SEQUENCE && constructed) )
+        return gpg_error (GPG_ERR_INV_OBJ);
+      totobjlen = objlen + hdrlen;
+      assert (save_p + totobjlen <= buffer + buflen);
+      memmove (buffer, save_p, totobjlen);
+    }
+
+  *cert = buffer;
+  buffer = NULL;
+  *certlen = totobjlen;
+
+ leave:
+  xfree (buffer);
+  return err;
+}
+
+
+/* Handle the READKEY command. On success a canonical encoded
+   S-expression with the public key will get stored at PK and its
+   length at PKLEN; the caller must release that buffer.  On error PK
+   and PKLEN are not changed and an error code is returned.  As of now
+   this function is only useful for the internal authentication key.
+   Other keys are automagically retrieved via by means of the
+   certificate parsing code in commands.c:cmd_readkey.  For internal
+   use PK and PKLEN may be NULL to just check for an existing key.  */
+static gpg_error_t
+do_readkey (app_t app, ctrl_t ctrl, const char *keyid, unsigned int flags,
+            unsigned char **pk, size_t *pklen)
+{
+  gpg_error_t err;
+  unsigned char *buffer[2];
+  size_t buflen[2];
+  unsigned short path[1] = { 0x4500 };
+
+  (void)ctrl;
+
+  if ((flags & APP_READKEY_FLAG_ADVANCED))
+    return GPG_ERR_NOT_SUPPORTED;
+
+  /* We use a generic name to retrieve PK.AUT.IFD-SPK.  */
+  if (!strcmp (keyid, "$IFDAUTHKEY") && app->app_local->nks_version >= 3)
+    ;
+  else /* Return the error code expected by cmd_readkey.  */
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+  /* Access the KEYD file which is always in the master directory.  */
+  err = iso7816_select_path (app_get_slot (app), path, DIM (path), 0);
+  if (err)
+    return err;
+  /* Due to the above select we need to re-select our application.  */
+  app->app_local->need_app_select = 1;
+  /* Get the two records.  */
+  err = iso7816_read_record (app->slot, 5, 1, 0, &buffer[0], &buflen[0]);
+  if (err)
+    return err;
+  if (all_zero_p (buffer[0], buflen[0]))
+    {
+      xfree (buffer[0]);
+      return gpg_error (GPG_ERR_NOT_FOUND);
+    }
+  err = iso7816_read_record (app->slot, 6, 1, 0, &buffer[1], &buflen[1]);
+  if (err)
+    {
+      xfree (buffer[0]);
+      return err;
+    }
+
+  if (pk && pklen)
+    {
+      *pk = make_canon_sexp_from_rsa_pk (buffer[0], buflen[0],
+                                         buffer[1], buflen[1],
+                                         pklen);
+      if (!*pk)
+        err = gpg_error_from_syserror ();
+    }
+
+  xfree (buffer[0]);
+  xfree (buffer[1]);
+  return err;
+}
+
+
+/* Handle the WRITEKEY command for NKS.  This function expects a
+   canonical encoded S-expression with the public key in KEYDATA and
+   its length in KEYDATALEN.  The only supported KEYID is
+   "$IFDAUTHKEY" to store the terminal key on the card.  Bit 0 of
+   FLAGS indicates whether an existing key shall get overwritten.
+   PINCB and PINCB_ARG are the usual arguments for the pinentry
+   callback.  */
+static gpg_error_t
+do_writekey (app_t app, ctrl_t ctrl,
+             const char *keyid, unsigned int flags,
+             gpg_error_t (*pincb)(void*, const char *, char **),
+             void *pincb_arg,
+             const unsigned char *keydata, size_t keydatalen)
+{
+  gpg_error_t err;
+  int force = (flags & 1);
+  const unsigned char *rsa_n = NULL;
+  const unsigned char *rsa_e = NULL;
+  size_t rsa_n_len, rsa_e_len;
+  unsigned int nbits;
+
+  (void)pincb;
+  (void)pincb_arg;
+
+  if (!strcmp (keyid, "$IFDAUTHKEY") && app->app_local->nks_version >= 3)
+    ;
+  else
+    return gpg_error (GPG_ERR_INV_ID);
+
+  if (!force && !do_readkey (app, ctrl, keyid, 0, NULL, NULL))
+    return gpg_error (GPG_ERR_EEXIST);
+
+  /* Parse the S-expression.  */
+  err = get_rsa_pk_from_canon_sexp (keydata, keydatalen,
+                                    &rsa_n, &rsa_n_len, &rsa_e, &rsa_e_len);
+  if (err)
+    goto leave;
+
+  /* Check that the parameters match the requirements.  */
+  nbits = app_help_count_bits (rsa_n, rsa_n_len);
+  if (nbits != 1024)
+    {
+      log_error (_("RSA modulus missing or not of size %d bits\n"), 1024);
+      err = gpg_error (GPG_ERR_BAD_PUBKEY);
+      goto leave;
+    }
+
+  nbits = app_help_count_bits (rsa_e, rsa_e_len);
+  if (nbits < 2 || nbits > 32)
+    {
+      log_error (_("RSA public exponent missing or larger than %d bits\n"),
+                 32);
+      err = gpg_error (GPG_ERR_BAD_PUBKEY);
+      goto leave;
+    }
+
+/*   /\* Store them.  *\/ */
+/*   err = verify_pin (app, 0, NULL, pincb, pincb_arg); */
+/*   if (err) */
+/*     goto leave; */
+
+  /* Send the MSE:Store_Public_Key.  */
+  err = gpg_error (GPG_ERR_NOT_IMPLEMENTED);
+/*   mse = xtrymalloc (1000); */
+
+/*   mse[0] = 0x80; /\* Algorithm reference.  *\/ */
+/*   mse[1] = 1; */
+/*   mse[2] = 0x17; */
+/*   mse[3] = 0x84; /\* Private key reference.  *\/ */
+/*   mse[4] = 1; */
+/*   mse[5] = 0x77; */
+/*   mse[6] = 0x7F; /\* Public key parameter.  *\/ */
+/*   mse[7] = 0x49; */
+/*   mse[8] = 0x81; */
+/*   mse[9] = 3 + 0x80 + 2 + rsa_e_len; */
+/*   mse[10] = 0x81; /\* RSA modulus of 128 byte.  *\/ */
+/*   mse[11] = 0x81; */
+/*   mse[12] = rsa_n_len; */
+/*   memcpy (mse+12, rsa_n, rsa_n_len); */
+/*   mse[10] = 0x82; /\* RSA public exponent of up to 4 bytes.  *\/ */
+/*   mse[12] = rsa_e_len; */
+/*   memcpy (mse+12, rsa_e, rsa_e_len); */
+/*   err = iso7816_manage_security_env (app->slot, 0x81, 0xB6, */
+/*                                      mse, sizeof mse); */
+
+ leave:
+  return err;
+}
+
+
+static gpg_error_t
+basic_pin_checks (const char *pinvalue, int minlen, int maxlen)
+{
+  if (strlen (pinvalue) < minlen)
+    {
+      log_error ("PIN is too short; minimum length is %d\n", minlen);
+      return gpg_error (GPG_ERR_BAD_PIN);
+    }
+  if (strlen (pinvalue) > maxlen)
+    {
+      log_error ("PIN is too large; maximum length is %d\n", maxlen);
+      return gpg_error (GPG_ERR_BAD_PIN);
+    }
+  return 0;
+}
+
+
+/* Verify the PIN if required.  */
+static gpg_error_t
+verify_pin (app_t app, int pwid, const char *desc,
+            gpg_error_t (*pincb)(void*, const char *, char **),
+            void *pincb_arg)
+{
+  pininfo_t pininfo;
+  int rc;
+
+  if (!desc)
+    desc = "PIN";
+
+  memset (&pininfo, 0, sizeof pininfo);
+  pininfo.fixedlen = -1;
+  pininfo.minlen = 6;
+  pininfo.maxlen = 16;
+
+  if (!opt.disable_pinpad
+      && !iso7816_check_pinpad (app->slot, ISO7816_VERIFY, &pininfo) )
+    {
+      rc = pincb (pincb_arg, desc, NULL);
+      if (rc)
+        {
+          log_info (_("PIN callback returned error: %s\n"),
+                    gpg_strerror (rc));
+          return rc;
+        }
+
+      rc = iso7816_verify_kp (app->slot, pwid, &pininfo);
+      pincb (pincb_arg, NULL, NULL);  /* Dismiss the prompt. */
+    }
+  else
+    {
+      char *pinvalue;
+
+      rc = pincb (pincb_arg, desc, &pinvalue);
+      if (rc)
+        {
+          log_info ("PIN callback returned error: %s\n", gpg_strerror (rc));
+          return rc;
+        }
+
+      rc = basic_pin_checks (pinvalue, pininfo.minlen, pininfo.maxlen);
+      if (rc)
+        {
+          xfree (pinvalue);
+          return rc;
+        }
+
+      rc = iso7816_verify (app->slot, pwid, pinvalue, strlen (pinvalue));
+      xfree (pinvalue);
+    }
+
+  if (rc)
+    {
+      if ( gpg_err_code (rc) == GPG_ERR_USE_CONDITIONS )
+        log_error (_("the NullPIN has not yet been changed\n"));
+      else
+        log_error ("verify PIN failed\n");
+      return rc;
+    }
+
+  return 0;
+}
+
+
+/* Create the signature and return the allocated result in OUTDATA.
+   If a PIN is required the PINCB will be used to ask for the PIN;
+   that callback should return the PIN in an allocated buffer and
+   store that in the 3rd argument.  */
+static gpg_error_t
+do_sign (app_t app, ctrl_t ctrl, const char *keyidstr, int hashalgo,
+         gpg_error_t (*pincb)(void*, const char *, char **),
+         void *pincb_arg,
+         const void *indata, size_t indatalen,
+         unsigned char **outdata, size_t *outdatalen )
+{
+  static unsigned char sha1_prefix[15] = /* Object ID is 1.3.14.3.2.26 */
+    { 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03,
+      0x02, 0x1a, 0x05, 0x00, 0x04, 0x14 };
+  static unsigned char rmd160_prefix[15] = /* Object ID is 1.3.36.3.2.1 */
+    { 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x24, 0x03,
+      0x02, 0x01, 0x05, 0x00, 0x04, 0x14 };
+  int rc, i;
+  int is_sigg = 0;
+  int fid;
+  unsigned char kid;
+  unsigned char data[83];   /* Must be large enough for a SHA-1 digest
+                               + the largest OID prefix. */
+  size_t datalen;
+
+  (void)ctrl;
+
+  if (!keyidstr || !*keyidstr)
+    return gpg_error (GPG_ERR_INV_VALUE);
+  switch (indatalen)
+    {
+    case 16: case 20: case 35: case 47: case 51: case 67: case 83: break;
+    default: return gpg_error (GPG_ERR_INV_VALUE);
+    }
+
+  /* Check that the provided ID is valid.  This is not really needed
+     but we do it to enforce correct usage by the caller. */
+  if (!strncmp (keyidstr, "NKS-NKS3.", 9) )
+    ;
+  else if (!strncmp (keyidstr, "NKS-DF01.", 9) )
+    ;
+  else if (!strncmp (keyidstr, "NKS-SIGG.", 9) )
+    is_sigg = 1;
+  else
+    return gpg_error (GPG_ERR_INV_ID);
+  keyidstr += 9;
+
+  rc = switch_application (app, is_sigg);
+  if (rc)
+    return rc;
+
+  if (is_sigg && app->app_local->sigg_is_msig)
+    {
+      log_info ("mass signature cards are not allowed\n");
+      return gpg_error (GPG_ERR_NOT_SUPPORTED);
+    }
+
+  if (!hexdigitp (keyidstr) || !hexdigitp (keyidstr+1)
+      || !hexdigitp (keyidstr+2) || !hexdigitp (keyidstr+3)
+      || keyidstr[4])
+    return gpg_error (GPG_ERR_INV_ID);
+  fid = xtoi_4 (keyidstr);
+  for (i=0; filelist[i].fid; i++)
+    if (filelist[i].iskeypair && filelist[i].fid == fid)
+      break;
+  if (!filelist[i].fid)
+    return gpg_error (GPG_ERR_NOT_FOUND);
+  if (!filelist[i].issignkey)
+    return gpg_error (GPG_ERR_INV_ID);
+  kid = filelist[i].kid;
+
+  /* Prepare the DER object from INDATA.  */
+  if (app->app_local->nks_version > 2 && (indatalen == 35
+                                          || indatalen == 47
+                                          || indatalen == 51
+                                          || indatalen == 67
+                                          || indatalen == 83))
+    {
+      /* The caller send data matching the length of the ASN.1 encoded
+         hash for SHA-{1,224,256,384,512}.  Assume that is okay.  */
+      assert (indatalen <= sizeof data);
+      memcpy (data, indata, indatalen);
+      datalen = indatalen;
+    }
+  else if (indatalen == 35)
+    {
+      /* Alright, the caller was so kind to send us an already
+         prepared DER object.  This is for TCOS 2. */
+      if (hashalgo == GCRY_MD_SHA1 && !memcmp (indata, sha1_prefix, 15))
+        ;
+      else if (hashalgo == GCRY_MD_RMD160 && !memcmp (indata,rmd160_prefix,15))
+        ;
+      else
+        return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
+      memcpy (data, indata, indatalen);
+      datalen = 35;
+    }
+  else if (indatalen == 20)
+    {
+      if (hashalgo == GCRY_MD_SHA1)
+        memcpy (data, sha1_prefix, 15);
+      else if (hashalgo == GCRY_MD_RMD160)
+        memcpy (data, rmd160_prefix, 15);
+      else
+        return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
+      memcpy (data+15, indata, indatalen);
+      datalen = 35;
+    }
+  else
+    return gpg_error (GPG_ERR_INV_VALUE);
+
+
+  /* Send an MSE for PSO:Computer_Signature.  */
+  if (app->app_local->nks_version > 2)
+    {
+      unsigned char mse[6];
+
+      mse[0] = 0x80; /* Algorithm reference.  */
+      mse[1] = 1;
+      mse[2] = 2;    /* RSA, card does pkcs#1 v1.5 padding, no ASN.1 check.  */
+      mse[3] = 0x84; /* Private key reference.  */
+      mse[4] = 1;
+      mse[5] = kid;
+      rc = iso7816_manage_security_env (app->slot, 0x41, 0xB6,
+                                        mse, sizeof mse);
+    }
+  /* Verify using PW1.CH.  */
+  if (!rc)
+    rc = verify_pin (app, 0, NULL, pincb, pincb_arg);
+  /* Compute the signature.  */
+  if (!rc)
+    rc = iso7816_compute_ds (app->slot, 0, data, datalen, 0,
+                             outdata, outdatalen);
+  return rc;
+}
+
+
+
+/* Decrypt the data in INDATA and return the allocated result in OUTDATA.
+   If a PIN is required the PINCB will be used to ask for the PIN; it
+   should return the PIN in an allocated buffer and put it into PIN.  */
+static gpg_error_t
+do_decipher (app_t app, ctrl_t ctrl, const char *keyidstr,
+             gpg_error_t (*pincb)(void*, const char *, char **),
+             void *pincb_arg,
+             const void *indata, size_t indatalen,
+             unsigned char **outdata, size_t *outdatalen,
+             unsigned int *r_info)
+{
+  int rc, i;
+  int is_sigg = 0;
+  int fid;
+  int kid;
+
+  (void)ctrl;
+  (void)r_info;
+
+  if (!keyidstr || !*keyidstr || !indatalen)
+    return gpg_error (GPG_ERR_INV_VALUE);
+
+  /* Check that the provided ID is valid.  This is not really needed
+     but we do it to enforce correct usage by the caller. */
+  if (!strncmp (keyidstr, "NKS-NKS3.", 9) )
+    ;
+  else if (!strncmp (keyidstr, "NKS-DF01.", 9) )
+    ;
+  else if (!strncmp (keyidstr, "NKS-SIGG.", 9) )
+    is_sigg = 1;
+  else
+    return gpg_error (GPG_ERR_INV_ID);
+  keyidstr += 9;
+
+  rc = switch_application (app, is_sigg);
+  if (rc)
+    return rc;
+
+  if (!hexdigitp (keyidstr) || !hexdigitp (keyidstr+1)
+      || !hexdigitp (keyidstr+2) || !hexdigitp (keyidstr+3)
+      || keyidstr[4])
+    return gpg_error (GPG_ERR_INV_ID);
+  fid = xtoi_4 (keyidstr);
+  for (i=0; filelist[i].fid; i++)
+    if (filelist[i].iskeypair && filelist[i].fid == fid)
+      break;
+  if (!filelist[i].fid)
+    return gpg_error (GPG_ERR_NOT_FOUND);
+  if (!filelist[i].isenckey)
+    return gpg_error (GPG_ERR_INV_ID);
+  kid = filelist[i].kid;
+
+  if (app->app_local->nks_version > 2)
+    {
+      unsigned char mse[6];
+      mse[0] = 0x80; /* Algorithm reference.  */
+      mse[1] = 1;
+      mse[2] = 0x0a; /* RSA no padding.  (0x1A is pkcs#1.5 padding.)  */
+      mse[3] = 0x84; /* Private key reference.  */
+      mse[4] = 1;
+      mse[5] = kid;
+      rc = iso7816_manage_security_env (app->slot, 0x41, 0xB8,
+                                        mse, sizeof mse);
+    }
+  else
+    {
+      static const unsigned char mse[] =
+        {
+          0x80, 1, 0x10, /* Select algorithm RSA. */
+          0x84, 1, 0x81  /* Select local secret key 1 for decryption. */
+        };
+      rc = iso7816_manage_security_env (app->slot, 0xC1, 0xB8,
+                                        mse, sizeof mse);
+
+    }
+
+  if (!rc)
+    rc = verify_pin (app, 0, NULL, pincb, pincb_arg);
+
+  /* Note that we need to use extended length APDUs for TCOS 3 cards.
+     Command chaining does not work.  */
+  if (!rc)
+    rc = iso7816_decipher (app->slot, app->app_local->nks_version > 2? 1:0,
+                           indata, indatalen, 0, 0x81,
+                           outdata, outdatalen);
+  return rc;
+}
+
+
+
+/* Parse a password ID string.  Returns NULL on error or a string
+   suitable as passphrase prompt on success.  On success stores the
+   reference value for the password at R_PWID and a flag indicating
+   that the SigG application is to be used at R_SIGG.  If NEW_MODE is
+   true, the returned description is suitable for a new Password.
+   Supported values for PWIDSTR are:
+
+     PW1.CH       - Global password 1
+     PW2.CH       - Global password 2
+     PW1.CH.SIG   - SigG password 1
+     PW2.CH.SIG   - SigG password 2
+ */
+static const char *
+parse_pwidstr (const char *pwidstr, int new_mode, int *r_sigg, int *r_pwid)
+{
+  const char *desc;
+
+  if (!pwidstr)
+    desc = NULL;
+  else if (!strcmp (pwidstr, "PW1.CH"))
+    {
+      *r_sigg = 0;
+      *r_pwid = 0x00;
+      /* TRANSLATORS: Do not translate the "|*|" prefixes but keep
+         them verbatim at the start of the string.  */
+      desc = (new_mode
+              ? _("|N|Please enter a new PIN for the standard keys.")
+              : _("||Please enter the PIN for the standard keys."));
+    }
+  else if (!strcmp (pwidstr, "PW2.CH"))
+    {
+      *r_pwid = 0x01;
+      desc = (new_mode
+              ? _("|NP|Please enter a new PIN Unblocking Code (PUK) "
+                  "for the standard keys.")
+              : _("|P|Please enter the PIN Unblocking Code (PUK) "
+                  "for the standard keys."));
+    }
+  else if (!strcmp (pwidstr, "PW1.CH.SIG"))
+    {
+      *r_pwid = 0x81;
+      *r_sigg = 1;
+      desc = (new_mode
+              ? _("|N|Please enter a new PIN for the key to create "
+                  "qualified signatures.")
+              : _("||Please enter the PIN for the key to create "
+                  "qualified signatures."));
+    }
+  else if (!strcmp (pwidstr, "PW2.CH.SIG"))
+    {
+      *r_pwid = 0x83;  /* Yes, that is 83 and not 82.  */
+      *r_sigg = 1;
+      desc = (new_mode
+              ? _("|NP|Please enter a new PIN Unblocking Code (PUK) "
+                  "for the key to create qualified signatures.")
+              : _("|P|Please enter the PIN Unblocking Code (PUK) "
+                  "for the key to create qualified signatures."));
+    }
+  else
+    {
+      *r_pwid = 0; /* Only to avoid gcc warning in calling function.  */
+      desc = NULL; /* Error.  */
+    }
+
+  return desc;
+}
+
+
+/* Handle the PASSWD command. See parse_pwidstr() for allowed values
+   for CHVNOSTR.  */
+static gpg_error_t
+do_change_pin (app_t app, ctrl_t ctrl,  const char *pwidstr,
+               unsigned int flags,
+               gpg_error_t (*pincb)(void*, const char *, char **),
+               void *pincb_arg)
+{
+  gpg_error_t err;
+  char *newpin = NULL;
+  char *oldpin = NULL;
+  size_t newpinlen;
+  size_t oldpinlen;
+  int is_sigg;
+  const char *newdesc;
+  int pwid;
+  pininfo_t pininfo;
+
+  (void)ctrl;
+
+  /* The minimum length is enforced by TCOS, the maximum length is
+     just a reasonable value.  */
+  memset (&pininfo, 0, sizeof pininfo);
+  pininfo.minlen = 6;
+  pininfo.maxlen = 16;
+
+  newdesc = parse_pwidstr (pwidstr, 1, &is_sigg, &pwid);
+  if (!newdesc)
+    return gpg_error (GPG_ERR_INV_ID);
+
+  if ((flags & APP_CHANGE_FLAG_CLEAR))
+    return gpg_error (GPG_ERR_UNSUPPORTED_OPERATION);
+
+  err = switch_application (app, is_sigg);
+  if (err)
+    return err;
+
+  if ((flags & APP_CHANGE_FLAG_NULLPIN))
+    {
+      /* With the nullpin flag, we do not verify the PIN - it would
+         fail if the Nullpin is still set.  */
+      oldpin = xtrycalloc (1, 6);
+      if (!oldpin)
+        {
+          err = gpg_error_from_syserror ();
+          goto leave;
+        }
+      oldpinlen = 6;
+    }
+  else
+    {
+      const char *desc;
+      int dummy1, dummy2;
+
+      if ((flags & APP_CHANGE_FLAG_RESET))
+        {
+          /* Reset mode: Ask for the alternate PIN.  */
+          const char *altpwidstr;
+
+          if (!strcmp (pwidstr, "PW1.CH"))
+            altpwidstr = "PW2.CH";
+          else if (!strcmp (pwidstr, "PW2.CH"))
+            altpwidstr = "PW1.CH";
+          else if (!strcmp (pwidstr, "PW1.CH.SIG"))
+            altpwidstr = "PW2.CH.SIG";
+          else if (!strcmp (pwidstr, "PW2.CH.SIG"))
+            altpwidstr = "PW1.CH.SIG";
+          else
+            {
+              err = gpg_error (GPG_ERR_BUG);
+              goto leave;
+            }
+          desc = parse_pwidstr (altpwidstr, 0, &dummy1, &dummy2);
+        }
+      else
+        {
+          /* Regular change mode:  Ask for the old PIN.  */
+          desc = parse_pwidstr (pwidstr, 0, &dummy1, &dummy2);
+        }
+      err = pincb (pincb_arg, desc, &oldpin);
+      if (err)
+        {
+          log_error ("error getting old PIN: %s\n", gpg_strerror (err));
+          goto leave;
+        }
+      oldpinlen = strlen (oldpin);
+      err = basic_pin_checks (oldpin, pininfo.minlen, pininfo.maxlen);
+      if (err)
+        goto leave;
+    }
+
+  err = pincb (pincb_arg, newdesc, &newpin);
+  if (err)
+    {
+      log_error (_("error getting new PIN: %s\n"), gpg_strerror (err));
+      goto leave;
+    }
+  newpinlen = strlen (newpin);
+
+  err = basic_pin_checks (newpin, pininfo.minlen, pininfo.maxlen);
+  if (err)
+    goto leave;
+
+  if ((flags & APP_CHANGE_FLAG_RESET))
+    {
+      char *data;
+      size_t datalen = oldpinlen + newpinlen;
+
+      data = xtrymalloc (datalen);
+      if (!data)
+        {
+          err = gpg_error_from_syserror ();
+          goto leave;
+        }
+      memcpy (data, oldpin, oldpinlen);
+      memcpy (data+oldpinlen, newpin, newpinlen);
+      err = iso7816_reset_retry_counter_with_rc (app->slot, pwid,
+                                                 data, datalen);
+      wipememory (data, datalen);
+      xfree (data);
+    }
+  else
+    err = iso7816_change_reference_data (app->slot, pwid,
+                                         oldpin, oldpinlen,
+                                         newpin, newpinlen);
+ leave:
+  xfree (oldpin);
+  xfree (newpin);
+  return err;
+}
+
+
+/* Perform a simple verify operation.  KEYIDSTR should be NULL or empty.  */
+static gpg_error_t
+do_check_pin (app_t app, ctrl_t ctrl, const char *pwidstr,
+              gpg_error_t (*pincb)(void*, const char *, char **),
+              void *pincb_arg)
+{
+  gpg_error_t err;
+  int pwid;
+  int is_sigg;
+  const char *desc;
+
+  (void)ctrl;
+
+  desc = parse_pwidstr (pwidstr, 0, &is_sigg, &pwid);
+  if (!desc)
+    return gpg_error (GPG_ERR_INV_ID);
+
+  err = switch_application (app, is_sigg);
+  if (err)
+    return err;
+
+  return verify_pin (app, pwid, desc, pincb, pincb_arg);
+}
+
+
+/* Return the version of the NKS application.  */
+static int
+get_nks_version (int slot)
+{
+  unsigned char *result = NULL;
+  size_t resultlen;
+  int type;
+
+  if (iso7816_apdu_direct (slot, "\x80\xaa\x06\x00\x00", 5, 0,
+                           NULL, &result, &resultlen))
+    return 2; /* NKS 2 does not support this command.  */
+
+  /* Example value:    04 11 19 22 21 6A 20 80 03 03 01 01 01 00 00 00
+                       vv tt ccccccccccccccccc aa bb cc vvvvvvvvvvv xx
+     vendor (Philips) -+  |  |                 |  |  |  |           |
+     chip type -----------+  |                 |  |  |  |           |
+     chip id ----------------+                 |  |  |  |           |
+     card type (3 - tcos 3) -------------------+  |  |  |           |
+     OS version of card type ---------------------+  |  |           |
+     OS release of card type ------------------------+  |           |
+     OS vendor internal version ------------------------+           |
+     RFU -----------------------------------------------------------+
+  */
+  if (resultlen < 16)
+    type = 0;  /* Invalid data returned.  */
+  else
+    type = result[8];
+  xfree (result);
+
+  return type;
+}
+
+
+/* If ENABLE_SIGG is true switch to the SigG application if not yet
+   active.  If false switch to the NKS application if not yet active.
+   Returns 0 on success.  */
+static gpg_error_t
+switch_application (app_t app, int enable_sigg)
+{
+  gpg_error_t err;
+
+  if (((app->app_local->sigg_active && enable_sigg)
+       || (!app->app_local->sigg_active && !enable_sigg))
+      && !app->app_local->need_app_select)
+    return 0;  /* Already switched.  */
+
+  log_info ("app-nks: switching to %s\n", enable_sigg? "SigG":"NKS");
+  if (enable_sigg)
+    err = iso7816_select_application (app->slot, aid_sigg, sizeof aid_sigg, 0);
+  else
+    err = iso7816_select_application (app->slot, aid_nks, sizeof aid_nks, 0);
+
+  if (!err && enable_sigg && app->app_local->nks_version >= 3
+      && !app->app_local->sigg_msig_checked)
+    {
+      /* Check whether this card is a mass signature card.  */
+      unsigned char *buffer;
+      size_t buflen;
+      const unsigned char *tmpl;
+      size_t tmpllen;
+
+      app->app_local->sigg_msig_checked = 1;
+      app->app_local->sigg_is_msig = 1;
+      err = iso7816_select_file (app->slot, 0x5349, 0);
+      if (!err)
+        err = iso7816_read_record (app->slot, 1, 1, 0, &buffer, &buflen);
+      if (!err)
+        {
+          tmpl = find_tlv (buffer, buflen, 0x7a, &tmpllen);
+          if (tmpl && tmpllen == 12
+              && !memcmp (tmpl,
+                          "\x93\x02\x00\x01\xA4\x06\x83\x01\x81\x83\x01\x83",
+                          12))
+            app->app_local->sigg_is_msig = 0;
+          xfree (buffer);
+        }
+      if (app->app_local->sigg_is_msig)
+        log_info ("This is a mass signature card\n");
+    }
+
+  if (!err)
+    {
+      app->app_local->need_app_select = 0;
+      app->app_local->sigg_active = enable_sigg;
+    }
+  else
+    log_error ("app-nks: error switching to %s: %s\n",
+               enable_sigg? "SigG":"NKS", gpg_strerror (err));
+
+  return err;
+}
+
+
+/* Select the NKS application.  */
+gpg_error_t
+app_select_nks (app_t app)
+{
+  int slot = app->slot;
+  int rc;
+
+  rc = iso7816_select_application (slot, aid_nks, sizeof aid_nks, 0);
+  if (!rc)
+    {
+      app->apptype = APPTYPE_NKS;
+
+      app->app_local = xtrycalloc (1, sizeof *app->app_local);
+      if (!app->app_local)
+        {
+          rc = gpg_error (gpg_err_code_from_errno (errno));
+          goto leave;
+        }
+
+      app->app_local->nks_version = get_nks_version (slot);
+      if (opt.verbose)
+        log_info ("Detected NKS version: %d\n", app->app_local->nks_version);
+
+      app->fnc.deinit = do_deinit;
+      app->fnc.learn_status = do_learn_status;
+      app->fnc.readcert = do_readcert;
+      app->fnc.readkey = do_readkey;
+      app->fnc.getattr = do_getattr;
+      app->fnc.setattr = NULL;
+      app->fnc.writekey = do_writekey;
+      app->fnc.genkey = NULL;
+      app->fnc.sign = do_sign;
+      app->fnc.auth = NULL;
+      app->fnc.decipher = do_decipher;
+      app->fnc.change_pin = do_change_pin;
+      app->fnc.check_pin = do_check_pin;
+   }
+
+ leave:
+  if (rc)
+    do_deinit (app);
+  return rc;
+}