Initial revision

1 files changed, 2352 insertions, 0 deletions

diff --git a/pwmanager/libcrypt/cipher/pubkey.c b/pwmanager/libcrypt/cipher/pubkey.c
new file mode 100644
index 0000000..45e816b
--- a/dev/null
+++ b/pwmanager/libcrypt/cipher/pubkey.c
@@ -0,0 +1,2352 @@
+/* pubkey.c  -	pubkey dispatcher
+ * Copyright (C) 1998,1999,2000,2002,2003 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser general Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+
+#include "g10lib.h"
+#include "mpi.h"
+#include "cipher.h"
+#include "ath.h"
+
+static gcry_err_code_t pubkey_decrypt (int algo, gcry_mpi_t *result,
+                                       gcry_mpi_t *data, gcry_mpi_t *skey,
+                                       int flags);
+static gcry_err_code_t pubkey_sign (int algo, gcry_mpi_t *resarr,
+                                    gcry_mpi_t hash, gcry_mpi_t *skey);
+static gcry_err_code_t pubkey_verify (int algo, gcry_mpi_t hash,
+                                      gcry_mpi_t *data, gcry_mpi_t *pkey,
+				     int (*cmp) (void *, gcry_mpi_t),
+                                      void *opaque);
+
+/* This is the list of the default public-key ciphers included in
+   libgcrypt.  */
+static struct pubkey_table_entry
+{
+  gcry_pk_spec_t *pubkey;
+  unsigned int algorithm;
+} pubkey_table[] =
+  {
+#if USE_RSA
+    { &_gcry_pubkey_spec_rsa, GCRY_PK_RSA },
+#endif
+#if USE_ELGAMAL
+    { &_gcry_pubkey_spec_elg, GCRY_PK_ELG },
+#endif
+#if USE_DSA
+    { &_gcry_pubkey_spec_dsa, GCRY_PK_DSA },
+#endif
+    { NULL, 0 },
+  };
+
+/* List of registered ciphers.  */
+static gcry_module_t pubkeys_registered;
+
+/* This is the lock protecting PUBKEYS_REGISTERED.  */
+static ath_mutex_t pubkeys_registered_lock;
+
+/* Flag to check wether the default pubkeys have already been
+   registered.  */
+static int default_pubkeys_registered;
+
+/* Convenient macro for registering the default digests.  */
+#define REGISTER_DEFAULT_PUBKEYS                   \
+  do                                               \
+    {                                              \
+      ath_mutex_lock (&pubkeys_registered_lock);   \
+      if (! default_pubkeys_registered)            \
+        {                                          \
+          gcry_pk_register_default ();         \
+          default_pubkeys_registered = 1;          \
+        }                                          \
+      ath_mutex_unlock (&pubkeys_registered_lock); \
+    }                                              \
+  while (0)
+
+/* These dummy functions are used in case a cipher implementation
+   refuses to provide it's own functions.  */
+
+static gcry_err_code_t
+dummy_generate (int algorithm, unsigned int nbits, unsigned long dummy,
+                gcry_mpi_t *skey, gcry_mpi_t **retfactors)
+{
+  log_bug ("no generate() for %d\n", algorithm);
+  return GPG_ERR_PUBKEY_ALGO;
+}
+
+static gcry_err_code_t
+dummy_check_secret_key (int algorithm, gcry_mpi_t *skey)
+{
+  log_bug ("no check_secret_key() for %d\n", algorithm);
+  return GPG_ERR_PUBKEY_ALGO;
+}
+
+static gcry_err_code_t
+dummy_encrypt (int algorithm, gcry_mpi_t *resarr, gcry_mpi_t data,
+               gcry_mpi_t *pkey, int flags)
+{
+  log_bug ("no encrypt() for %d\n", algorithm);
+  return GPG_ERR_PUBKEY_ALGO;
+}
+
+static gcry_err_code_t
+dummy_decrypt (int algorithm, gcry_mpi_t *result, gcry_mpi_t *data,
+               gcry_mpi_t *skey, int flags)
+{
+  log_bug ("no decrypt() for %d\n", algorithm);
+  return GPG_ERR_PUBKEY_ALGO;
+}
+
+static gcry_err_code_t
+dummy_sign (int algorithm, gcry_mpi_t *resarr, gcry_mpi_t data,
+            gcry_mpi_t *skey)
+{
+  log_bug ("no sign() for %d\n", algorithm);
+  return GPG_ERR_PUBKEY_ALGO;
+}
+
+static gcry_err_code_t
+dummy_verify (int algorithm, gcry_mpi_t hash, gcry_mpi_t *data,
+              gcry_mpi_t *pkey,
+	      int (*cmp) (void *, gcry_mpi_t), void *opaquev)
+{
+  log_bug ("no verify() for %d\n", algorithm);
+  return GPG_ERR_PUBKEY_ALGO;
+}
+
+static unsigned
+dummy_get_nbits (int algorithm, gcry_mpi_t *pkey)
+{
+  log_bug ("no get_nbits() for %d\n", algorithm);
+  return 0;
+}
+
+/* Internal function.  Register all the pubkeys included in
+   PUBKEY_TABLE.  Returns zero on success or an error code.  */
+static void
+gcry_pk_register_default (void)
+{
+  gcry_err_code_t err = 0;
+  int i;
+  
+  for (i = 0; (! err) && pubkey_table[i].pubkey; i++)
+    {
+#define pubkey_use_dummy(func)                       \
+      if (! pubkey_table[i].pubkey->func)            \
+	pubkey_table[i].pubkey->func = dummy_##func;
+
+      pubkey_use_dummy (generate);
+      pubkey_use_dummy (check_secret_key);
+      pubkey_use_dummy (encrypt);
+      pubkey_use_dummy (decrypt);
+      pubkey_use_dummy (sign);
+      pubkey_use_dummy (verify);
+      pubkey_use_dummy (get_nbits);
+#undef pubkey_use_dummy
+      err = _gcry_module_add (&pubkeys_registered,
+			      pubkey_table[i].algorithm,
+			      (void *) pubkey_table[i].pubkey, NULL);
+    }
+
+  if (err)
+    BUG ();
+}
+
+/* Internal callback function.  Used via _gcry_module_lookup.  */
+static int
+gcry_pk_lookup_func_name (void *spec, void *data)
+{
+  gcry_pk_spec_t *pubkey = (gcry_pk_spec_t *) spec;
+  char *name = (char *) data;
+  char **aliases = pubkey->aliases;
+  int ret = stricmp (name, pubkey->name);
+
+  while (ret && *aliases)
+    ret = stricmp (name, *aliases++);
+
+  return ! ret;
+}
+
+/* Internal function.  Lookup a pubkey entry by it's name.  */
+static gcry_module_t 
+gcry_pk_lookup_name (const char *name)
+{
+  gcry_module_t pubkey;
+
+  pubkey = _gcry_module_lookup (pubkeys_registered, (void *) name,
+				gcry_pk_lookup_func_name);
+
+  return pubkey;
+}
+
+/* Register a new pubkey module whose specification can be found in
+   PUBKEY.  On success, a new algorithm ID is stored in ALGORITHM_ID
+   and a pointer representhing this module is stored in MODULE.  */
+gcry_error_t
+gcry_pk_register (gcry_pk_spec_t *pubkey,
+		  unsigned int *algorithm_id,
+		  gcry_module_t *module)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+  gcry_module_t mod;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  err = _gcry_module_add (&pubkeys_registered, 0,
+			  (void *) pubkey, &mod);
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  if (! err)
+    {
+      *module = mod;
+      *algorithm_id = mod->mod_id;
+    }
+
+  return err;
+}
+
+/* Unregister the pubkey identified by ID, which must have been
+   registered with gcry_pk_register.  */
+void
+gcry_pk_unregister (gcry_module_t module)
+{
+  ath_mutex_lock (&pubkeys_registered_lock);
+  _gcry_module_release (module);
+  ath_mutex_unlock (&pubkeys_registered_lock);
+}
+
+static void
+release_mpi_array (gcry_mpi_t *array)
+{
+  for (; *array; array++)
+    {
+      mpi_free(*array);
+      *array = NULL;
+    }
+}
+
+/****************
+ * Map a string to the pubkey algo
+ */
+int
+gcry_pk_map_name (const char *string)
+{
+  gcry_module_t pubkey;
+  int algorithm = 0;
+
+  if (!string)
+    return 0;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = gcry_pk_lookup_name (string);
+  if (pubkey)
+    {
+      algorithm = pubkey->mod_id;
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return algorithm;
+}
+
+
+/****************
+ * Map a pubkey algo to a string
+ */
+const char *
+gcry_pk_algo_name (int algorithm)
+{
+  const char *name = NULL;
+  gcry_module_t pubkey;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      name = ((gcry_pk_spec_t *) pubkey->spec)->name;
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return name;
+}
+
+
+/* A special version of gcry_pk_algo name to return the first aliased
+   name of the algorithm.  This is required to adhere to the spki
+   specs where the algorithm names are lowercase. */
+const char *
+_gcry_pk_aliased_algo_name (int algorithm)
+{
+  const char *name = NULL;
+  gcry_module_t module;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  module = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (module)
+    {
+      gcry_pk_spec_t *pubkey = (gcry_pk_spec_t *) module->spec;
+
+      name = pubkey->aliases? *pubkey->aliases : NULL;
+      if (!name || !*name)
+        name = pubkey->name;
+      _gcry_module_release (module);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return name;
+}
+
+
+static void
+disable_pubkey_algo (int algorithm)
+{
+  gcry_module_t pubkey;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      if (! (pubkey-> flags & FLAG_MODULE_DISABLED))
+	pubkey->flags |= FLAG_MODULE_DISABLED;
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+}
+
+
+/****************
+ * A USE of 0 means: don't care.
+ */
+static gcry_err_code_t
+check_pubkey_algo (int algorithm, unsigned use)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+  gcry_pk_spec_t *pubkey;
+  gcry_module_t module;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  module = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (module)
+    {
+      pubkey = (gcry_pk_spec_t *) module->spec;
+
+      if (((use & GCRY_PK_USAGE_SIGN)
+	   && (! (pubkey->use & GCRY_PK_USAGE_SIGN)))
+	  || ((use & GCRY_PK_USAGE_ENCR)
+	      && (! (pubkey->use & GCRY_PK_USAGE_ENCR))))
+	err = GPG_ERR_WRONG_PUBKEY_ALGO;
+      else if (module->flags & FLAG_MODULE_DISABLED)
+	err = GPG_ERR_PUBKEY_ALGO;
+      _gcry_module_release (module);
+    }
+  else
+    err = GPG_ERR_PUBKEY_ALGO;
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return err;
+}
+
+
+/****************
+ * Return the number of public key material numbers
+ */
+static int
+pubkey_get_npkey (int algorithm)
+{
+  gcry_module_t pubkey;
+  int npkey = 0;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      npkey = strlen (((gcry_pk_spec_t *) pubkey->spec)->elements_pkey);
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return npkey;
+}
+
+/****************
+ * Return the number of secret key material numbers
+ */
+static int
+pubkey_get_nskey (int algorithm)
+{
+  gcry_module_t pubkey;
+  int nskey = 0;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      nskey = strlen (((gcry_pk_spec_t *) pubkey->spec)->elements_skey);
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return nskey;
+}
+
+/****************
+ * Return the number of signature material numbers
+ */
+static int
+pubkey_get_nsig (int algorithm)
+{
+  gcry_module_t pubkey;
+  int nsig = 0;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      nsig = strlen (((gcry_pk_spec_t *) pubkey->spec)->elements_sig);
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return nsig;
+}
+
+/****************
+ * Return the number of encryption material numbers
+ */
+static int
+pubkey_get_nenc (int algorithm)
+{
+  gcry_module_t pubkey;
+  int nenc = 0;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      nenc = strlen (((gcry_pk_spec_t *) pubkey->spec)->elements_enc);
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return nenc;
+}
+
+
+static gcry_err_code_t
+pubkey_generate (int algorithm, unsigned int nbits, unsigned long use_e,
+                 gcry_mpi_t *skey, gcry_mpi_t **retfactors)
+{
+  gcry_err_code_t err = GPG_ERR_PUBKEY_ALGO;
+  gcry_module_t pubkey;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      err = ((gcry_pk_spec_t *) pubkey->spec)->generate 
+        (algorithm, nbits, use_e, skey, retfactors);
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return err;
+}
+
+static gcry_err_code_t
+pubkey_check_secret_key (int algorithm, gcry_mpi_t *skey)
+{
+  gcry_err_code_t err = GPG_ERR_PUBKEY_ALGO;
+  gcry_module_t pubkey;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    {
+      err = ((gcry_pk_spec_t *) pubkey->spec)->check_secret_key
+        (algorithm, skey);
+      _gcry_module_release (pubkey);
+    }
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return err;
+}
+
+
+/****************
+ * This is the interface to the public key encryption.  Encrypt DATA
+ * with PKEY and put it into RESARR which should be an array of MPIs
+ * of size PUBKEY_MAX_NENC (or less if the algorithm allows this -
+ * check with pubkey_get_nenc() )
+ */
+static gcry_err_code_t
+pubkey_encrypt (int algorithm, gcry_mpi_t *resarr, gcry_mpi_t data,
+                gcry_mpi_t *pkey, int flags)
+{
+  gcry_pk_spec_t *pubkey;
+  gcry_module_t module;
+  gcry_err_code_t rc;
+  int i;
+
+  if (DBG_CIPHER)
+    {
+      log_debug ("pubkey_encrypt: algo=%d\n", algorithm);
+      for(i = 0; i < pubkey_get_npkey (algorithm); i++)
+	log_mpidump ("  pkey:", pkey[i]);
+      log_mpidump ("  data:", data);
+    }
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  module = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (module)
+    {
+      pubkey = (gcry_pk_spec_t *) module->spec;
+      rc = pubkey->encrypt (algorithm, resarr, data, pkey, flags);
+      _gcry_module_release (module);
+      goto ready;
+    }
+  rc = GPG_ERR_PUBKEY_ALGO;
+
+ ready:
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  if (!rc && DBG_CIPHER)
+    {
+      for(i = 0; i < pubkey_get_nenc (algorithm); i++)
+	log_mpidump("  encr:", resarr[i] );
+    }
+  return rc;
+}
+
+
+/****************
+ * This is the interface to the public key decryption.
+ * ALGO gives the algorithm to use and this implicitly determines
+ * the size of the arrays.
+ * result is a pointer to a mpi variable which will receive a
+ * newly allocated mpi or NULL in case of an error.
+ */
+static gcry_err_code_t
+pubkey_decrypt (int algorithm, gcry_mpi_t *result, gcry_mpi_t *data,
+                gcry_mpi_t *skey, int flags)
+{
+  gcry_pk_spec_t *pubkey;
+  gcry_module_t module;
+  gcry_err_code_t rc;
+  int i;
+
+  *result = NULL; /* so the caller can always do a mpi_free */
+  if (DBG_CIPHER)
+    {
+      log_debug ("pubkey_decrypt: algo=%d\n", algorithm);
+      for(i = 0; i < pubkey_get_nskey (algorithm); i++)
+	log_mpidump ("  skey:", skey[i]);
+      for(i = 0; i < pubkey_get_nenc (algorithm); i++)
+	log_mpidump ("  data:", data[i]);
+    }
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  module = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (module)
+    {
+      pubkey = (gcry_pk_spec_t *) module->spec;
+      rc = pubkey->decrypt (algorithm, result, data, skey, flags);
+      _gcry_module_release (module);
+      goto ready;
+    }
+
+  rc = GPG_ERR_PUBKEY_ALGO;
+  
+ ready:
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  if (! rc && DBG_CIPHER)
+    log_mpidump (" plain:", *result);
+
+  return rc;
+}
+
+
+/****************
+ * This is the interface to the public key signing.
+ * Sign data with skey and put the result into resarr which
+ * should be an array of MPIs of size PUBKEY_MAX_NSIG (or less if the
+ * algorithm allows this - check with pubkey_get_nsig() )
+ */
+static gcry_err_code_t
+pubkey_sign (int algorithm, gcry_mpi_t *resarr, gcry_mpi_t data,
+             gcry_mpi_t *skey)
+{
+  gcry_pk_spec_t *pubkey;
+  gcry_module_t module;
+  gcry_err_code_t rc;
+  int i;
+
+  if (DBG_CIPHER)
+    {
+      log_debug ("pubkey_sign: algo=%d\n", algorithm);
+      for(i = 0; i < pubkey_get_nskey (algorithm); i++)
+	log_mpidump ("  skey:", skey[i]);
+      log_mpidump("  data:", data );
+    }
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  module = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (module)
+    {
+      pubkey = (gcry_pk_spec_t *) module->spec;
+      rc = pubkey->sign (algorithm, resarr, data, skey);
+      _gcry_module_release (module);
+      goto ready;
+    }
+
+  rc = GPG_ERR_PUBKEY_ALGO;
+
+ ready:
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  if (! rc && DBG_CIPHER)
+    for (i = 0; i < pubkey_get_nsig (algorithm); i++)
+      log_mpidump ("   sig:", resarr[i]);
+
+  return rc;
+}
+
+/****************
+ * Verify a public key signature.
+ * Return 0 if the signature is good
+ */
+static gcry_err_code_t
+pubkey_verify (int algorithm, gcry_mpi_t hash, gcry_mpi_t *data,
+               gcry_mpi_t *pkey,
+	       int (*cmp)(void *, gcry_mpi_t), void *opaquev)
+{
+  gcry_pk_spec_t *pubkey;
+  gcry_module_t module;
+  gcry_err_code_t rc;
+  int i;
+
+  if (DBG_CIPHER)
+    {
+      log_debug ("pubkey_verify: algo=%d\n", algorithm);
+      for (i = 0; i < pubkey_get_npkey (algorithm); i++)
+	log_mpidump ("  pkey:", pkey[i]);
+      for (i = 0; i < pubkey_get_nsig (algorithm); i++)
+	log_mpidump ("   sig:", data[i]);
+      log_mpidump ("  hash:", hash);
+    }
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  module = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (module)
+    {
+      pubkey = (gcry_pk_spec_t *) module->spec;
+      rc = pubkey->verify (algorithm, hash, data, pkey, cmp, opaquev);
+      _gcry_module_release (module);
+      goto ready;
+    }
+
+  rc = GPG_ERR_PUBKEY_ALGO;
+
+ ready:
+  ath_mutex_unlock (&pubkeys_registered_lock);
+  return rc;
+}
+
+
+/* Internal function.   */
+static gcry_err_code_t
+sexp_elements_extract (gcry_sexp_t key_sexp, const char *element_names,
+		       gcry_mpi_t *elements)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+  int i, idx;
+  const char *name;
+  gcry_sexp_t list;
+
+  for (name = element_names, idx = 0; *name && !err; name++, idx++)
+    {
+      list = gcry_sexp_find_token (key_sexp, name, 1);
+      if (! list)
+	err = GPG_ERR_NO_OBJ;
+      else
+	{
+	  elements[idx] = gcry_sexp_nth_mpi (list, 1, GCRYMPI_FMT_USG);
+	  gcry_sexp_release (list);
+	  if (! elements[idx])
+	    err = GPG_ERR_INV_OBJ;
+	}
+    }
+
+  if (err)
+    {
+      for (i = 0; i < idx; i++)
+        if (elements[i])
+          gcry_free (elements[i]);
+    }
+  return err;
+}
+
+/****************
+ * Convert a S-Exp with either a private or a public key to our
+ * internal format. Currently we do only support the following
+ * algorithms:
+ *    dsa
+ *    rsa
+ *    openpgp-dsa
+ *    openpgp-rsa
+ *    openpgp-elg
+ *    openpgp-elg-sig
+ * Provide a SE with the first element be either "private-key" or
+ * or "public-key". It is followed by a list with its first element
+ * be one of the above algorithm identifiers and the remaning
+ * elements are pairs with parameter-id and value.
+ * NOTE: we look through the list to find a list beginning with
+ * "private-key" or "public-key" - the first one found is used.
+ *
+ * FIXME: Allow for encrypted secret keys here.
+ *
+ * Returns: A pointer to an allocated array of MPIs if the return value is
+ *	    zero; the caller has to release this array.
+ *
+ * Example of a DSA public key:
+ *  (private-key
+ *    (dsa
+ *	(p <mpi>)
+ *	(g <mpi>)
+ *	(y <mpi>)
+ *	(x <mpi>)
+ *    )
+ *  )
+ * The <mpi> are expected to be in GCRYMPI_FMT_USG
+ */
+static gcry_err_code_t
+sexp_to_key (gcry_sexp_t sexp, int want_private, gcry_mpi_t **retarray,
+             gcry_module_t *retalgo)
+{
+    gcry_sexp_t list, l2;
+    const char *name;
+    size_t n;
+    const char *elems;
+    gcry_mpi_t *array;
+    gcry_err_code_t err = GPG_ERR_NO_ERROR;
+    gcry_module_t module;
+    gcry_pk_spec_t *pubkey;
+
+    /* check that the first element is valid */
+    list = gcry_sexp_find_token( sexp, want_private? "private-key"
+						    :"public-key", 0 );
+    if( !list )
+	return GPG_ERR_INV_OBJ; /* Does not contain a public-
+                                   or private-key object */
+    l2 = gcry_sexp_cadr( list );
+    gcry_sexp_release ( list );
+    list = l2;
+    name = gcry_sexp_nth_data( list, 0, &n );
+    if( !name ) {
+	gcry_sexp_release ( list );
+	return GPG_ERR_INV_OBJ; /* invalid structure of object */
+    }
+
+    {
+      char *name_terminated = gcry_xmalloc (n + 1);
+      memcpy (name_terminated, name, n);
+      name_terminated[n] = 0;
+
+      ath_mutex_lock (&pubkeys_registered_lock);
+      module = gcry_pk_lookup_name (name_terminated);
+      ath_mutex_unlock (&pubkeys_registered_lock);
+
+      gcry_free (name_terminated);
+    }
+
+    if (! module)
+      {
+	gcry_sexp_release (list);
+	return GPG_ERR_PUBKEY_ALGO; /* unknown algorithm */
+      }
+    else
+      pubkey = (gcry_pk_spec_t *) module->spec;
+
+    elems = want_private ? pubkey->elements_skey : pubkey->elements_pkey;
+    array = gcry_calloc (strlen (elems) + 1, sizeof (*array));
+    if (! array)
+      err = gpg_err_code_from_errno (errno);
+    if (! err)
+      err = sexp_elements_extract (list, elems, array);
+
+    if (list)
+      gcry_sexp_release (list);
+
+    if (err)
+      {
+	if (array)
+	  gcry_free (array);
+
+	ath_mutex_lock (&pubkeys_registered_lock);
+	_gcry_module_release (module);
+	ath_mutex_unlock (&pubkeys_registered_lock);
+      }
+    else
+      {
+	*retarray = array;
+	*retalgo = module;
+      }
+
+    return err;
+}
+
+static gcry_err_code_t
+sexp_to_sig (gcry_sexp_t sexp, gcry_mpi_t **retarray,
+	     gcry_module_t *retalgo)
+{
+    gcry_sexp_t list, l2;
+    const char *name;
+    size_t n;
+    const char *elems;
+    gcry_mpi_t *array;
+    gcry_err_code_t err = GPG_ERR_NO_ERROR;
+    gcry_module_t module;
+    gcry_pk_spec_t *pubkey;
+
+    /* check that the first element is valid */
+    list = gcry_sexp_find_token( sexp, "sig-val" , 0 );
+    if( !list )
+	return GPG_ERR_INV_OBJ; /* Does not contain a signature value object */
+    l2 = gcry_sexp_nth (list, 1);
+    if(! l2)
+      {
+	gcry_sexp_release (list);
+	return GPG_ERR_NO_OBJ; /* no cadr for the sig object */
+      }
+    name = gcry_sexp_nth_data( l2, 0, &n );
+    if( !name ) {
+      	gcry_sexp_release ( list );
+      	gcry_sexp_release ( l2 );
+	return GPG_ERR_INV_OBJ; /* invalid structure of object */
+    }
+    else if (n == 5 && (! memcmp (name, "flags", 5))) {
+      /* Skip flags, since they are not used but just here for the
+	 sake of consistent S-expressions.  */
+      gcry_sexp_release (l2);
+      l2 = gcry_sexp_nth (list, 2);
+      if (! l2)
+	{
+	  gcry_sexp_release (list);
+	  return GPG_ERR_INV_OBJ;
+	}
+      name = gcry_sexp_nth_data (l2, 0, &n);
+    }
+      
+    {
+      char *name_terminated = gcry_xmalloc (n + 1);
+      memcpy (name_terminated, name, n);
+      name_terminated[n] = 0;
+      
+      ath_mutex_lock (&pubkeys_registered_lock);
+      module = gcry_pk_lookup_name (name_terminated);
+      ath_mutex_unlock (&pubkeys_registered_lock);
+
+      gcry_free (name_terminated);
+    }
+
+    if (! module)
+      {
+	gcry_sexp_release (l2);
+	gcry_sexp_release (list);
+	return GPG_ERR_PUBKEY_ALGO; /* unknown algorithm */
+      }
+    else
+      pubkey = (gcry_pk_spec_t *) module->spec;
+
+    elems = pubkey->elements_sig;
+    array = gcry_calloc (strlen (elems) + 1 , sizeof (*array));
+    if (! array)
+      err = gpg_err_code_from_errno (errno);
+
+    if (! err)
+      err = sexp_elements_extract (list, elems, array);
+
+    gcry_sexp_release (l2);
+    gcry_sexp_release (list);
+
+    if (err)
+      {
+	ath_mutex_lock (&pubkeys_registered_lock);
+	_gcry_module_release (module);
+	ath_mutex_unlock (&pubkeys_registered_lock);
+
+	if (array)
+	  gcry_free (array);
+      }
+    else
+      {
+	*retarray = array;
+	*retalgo = module;
+      }
+
+    return err;
+}
+
+
+/****************
+ * Take sexp and return an array of MPI as used for our internal decrypt
+ * function.
+ * s_data = (enc-val
+ *           [(flags [pkcs1])
+ *	      (<algo>
+ *		(<param_name1> <mpi>)
+ *		...
+ *		(<param_namen> <mpi>)
+ *	      ))
+ * RET_MODERN is set to true when at least an empty flags list has been found.
+ */
+static gcry_err_code_t
+sexp_to_enc (gcry_sexp_t sexp, gcry_mpi_t **retarray, gcry_module_t *retalgo,
+             int *ret_modern, int *ret_want_pkcs1, int *flags)
+{
+  gcry_sexp_t list = NULL, l2 = NULL;
+  gcry_pk_spec_t *pubkey = NULL;
+  gcry_module_t module = NULL;
+  const char *name;
+  size_t n;
+  int parsed_flags = 0;
+  const char *elems;
+  gcry_mpi_t *array = NULL;
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+
+  *ret_want_pkcs1 = 0;
+  *ret_modern = 0;
+
+  /* check that the first element is valid */
+  list = gcry_sexp_find_token (sexp, "enc-val" , 0);
+  if (! list)
+    {
+      err = GPG_ERR_INV_OBJ; /* Does not contain an encrypted value object */
+      goto leave;
+    }
+
+  l2 = gcry_sexp_nth (list, 1);
+  if (! l2)
+    {
+      err = GPG_ERR_NO_OBJ; /* no cdr for the data object */
+      goto leave;
+    }
+
+  /* Extract identifier of sublist.  */
+  name = gcry_sexp_nth_data (l2, 0, &n);
+  if (! name)
+    {
+      err = GPG_ERR_INV_OBJ; /* invalid structure of object */
+      goto leave;
+    }
+  
+  if ((n == 5) && (! memcmp (name, "flags", 5)))
+    {
+      /* There is a flags element - process it */
+      const char *s;
+      int i;
+      
+      *ret_modern = 1;
+      for (i = gcry_sexp_length (l2) - 1; i > 0; i--)
+        {
+          s = gcry_sexp_nth_data (l2, i, &n);
+          if (! s)
+            ; /* not a data element - ignore */
+          else if (n == 3 && ! memcmp (s, "raw", 3))
+            ; /* just a dummy because it is the default */
+          else if (n == 5 && ! memcmp (s, "pkcs1", 5))
+            *ret_want_pkcs1 = 1;
+          else if (n == 11 && ! memcmp (s, "no-blinding", 11))
+            parsed_flags |= PUBKEY_FLAG_NO_BLINDING;
+          else
+            {
+              err = GPG_ERR_INV_FLAG;
+              goto leave;
+            }
+        }
+      
+      /* Get the next which has the actual data */
+      gcry_sexp_release (l2);
+      l2 = gcry_sexp_nth (list, 2);
+      if (! l2)
+        {
+          err = GPG_ERR_NO_OBJ; /* no cdr for the data object */
+          goto leave;
+        }
+
+      /* Extract sublist identifier.  */
+      name = gcry_sexp_nth_data (l2, 0, &n);
+      if (! name)
+        {
+          err = GPG_ERR_INV_OBJ; /* invalid structure of object */
+          goto leave;
+        }
+
+      gcry_sexp_release (list);
+      list = l2;
+      l2 = NULL;
+    }
+
+  {
+    char *name_terminated = gcry_xmalloc (n + 1);
+    memcpy (name_terminated, name, n);
+    name_terminated[n] = 0;
+    
+    ath_mutex_lock (&pubkeys_registered_lock);
+    module = gcry_pk_lookup_name (name_terminated);
+    ath_mutex_unlock (&pubkeys_registered_lock);
+    
+    gcry_free (name_terminated);
+    
+    if (! module)
+      {
+        err = GPG_ERR_PUBKEY_ALGO; /* unknown algorithm */
+        goto leave;
+      }
+    pubkey = (gcry_pk_spec_t *) module->spec;
+  }
+
+  elems = pubkey->elements_enc;
+  array = gcry_calloc (strlen (elems) + 1, sizeof (*array));
+  if (! array)
+    {
+      err = gpg_err_code_from_errno (errno);
+      goto leave;
+    }
+
+  err = sexp_elements_extract (list, elems, array);
+
+ leave:
+  if (list)
+    gcry_sexp_release (list);
+  if (l2)
+    gcry_sexp_release (l2);
+
+  if (err)
+    {
+      ath_mutex_lock (&pubkeys_registered_lock);
+      _gcry_module_release (module);
+      ath_mutex_unlock (&pubkeys_registered_lock);
+      if (array)
+	gcry_free (array);
+    }
+  else
+    {
+      *retarray = array;
+      *retalgo = module;
+      *flags = parsed_flags;
+    }
+
+  return err;
+}
+
+/* Take the hash value and convert into an MPI, suitable for for
+   passing to the low level functions.  We currently support the
+   old style way of passing just a MPI and the modern interface which
+   allows to pass flags so that we can choose between raw and pkcs1
+   padding - may be more padding options later. 
+
+   (<mpi>)
+   or
+   (data
+    [(flags [pkcs1])]
+    [(hash <algo> <value>)]
+    [(value <text>)]
+   )
+   
+   Either the VALUE or the HASH element must be present for use
+   with signatures.  VALUE is used for encryption.
+
+   NBITS is the length of the key in bits. 
+
+*/
+static gcry_err_code_t
+sexp_data_to_mpi (gcry_sexp_t input, unsigned int nbits, gcry_mpi_t *ret_mpi,
+                  int for_encryption, int *flags)
+{
+  gcry_err_code_t rc = 0;
+  gcry_sexp_t ldata, lhash, lvalue;
+  int i;
+  size_t n;
+  const char *s;
+  int is_raw = 0, is_pkcs1 = 0, unknown_flag=0; 
+  int parsed_flags = 0, dummy_flags;
+
+  if (! flags)
+    flags = &dummy_flags;
+  
+  *ret_mpi = NULL;
+  ldata = gcry_sexp_find_token (input, "data", 0);
+  if (!ldata)
+    { /* assume old style */
+      *ret_mpi = gcry_sexp_nth_mpi (input, 0, 0);
+      return *ret_mpi ? GPG_ERR_NO_ERROR : GPG_ERR_INV_OBJ;
+    }
+
+  /* see whether there is a flags object */
+  {
+    gcry_sexp_t lflags = gcry_sexp_find_token (ldata, "flags", 0);
+    if (lflags)
+      { /* parse the flags list. */
+        for (i=gcry_sexp_length (lflags)-1; i > 0; i--)
+          {
+            s = gcry_sexp_nth_data (lflags, i, &n);
+            if (!s)
+              ; /* not a data element*/
+            else if ( n == 3 && !memcmp (s, "raw", 3))
+              is_raw = 1;
+            else if ( n == 5 && !memcmp (s, "pkcs1", 5))
+              is_pkcs1 = 1;
+	    else if (n == 11 && ! memcmp (s, "no-blinding", 11))
+	      parsed_flags |= PUBKEY_FLAG_NO_BLINDING;
+            else
+              unknown_flag = 1;
+          }
+        gcry_sexp_release (lflags);
+      }
+  }
+
+  if (!is_pkcs1 && !is_raw)
+    is_raw = 1; /* default to raw */
+
+  /* Get HASH or MPI */
+  lhash = gcry_sexp_find_token (ldata, "hash", 0);
+  lvalue = lhash? NULL : gcry_sexp_find_token (ldata, "value", 0);
+
+  if (!(!lhash ^ !lvalue))
+    rc = GPG_ERR_INV_OBJ; /* none or both given */
+  else if (unknown_flag)
+    rc = GPG_ERR_INV_FLAG;
+  else if (is_raw && is_pkcs1 && !for_encryption)
+    rc = GPG_ERR_CONFLICT;
+  else if (is_raw && lvalue)
+    {
+      *ret_mpi = gcry_sexp_nth_mpi (lvalue, 1, 0);
+      if (!*ret_mpi)
+        rc = GPG_ERR_INV_OBJ;
+    }
+  else if (is_pkcs1 && lvalue && for_encryption)
+    { /* Create pkcs#1 block type 2 padding. */
+      unsigned char *frame = NULL;
+      size_t nframe = (nbits+7) / 8;
+      const void * value;
+      size_t valuelen;
+      unsigned char *p;
+
+      if ( !(value=gcry_sexp_nth_data (lvalue, 1, &valuelen)) || !valuelen )
+        rc = GPG_ERR_INV_OBJ;
+      else if (valuelen + 7 > nframe || !nframe)
+        {
+          /* Can't encode a VALUELEN value in a NFRAME bytes frame. */
+          rc = GPG_ERR_TOO_SHORT; /* the key is too short */
+        }
+      else if ( !(frame = gcry_malloc_secure (nframe)))
+        rc = gpg_err_code_from_errno (errno);
+      else
+        {
+          n = 0;
+          frame[n++] = 0;
+          frame[n++] = 2; /* block type */
+          i = nframe - 3 - valuelen;
+          assert (i > 0);
+          p = gcry_random_bytes_secure (i, GCRY_STRONG_RANDOM);
+          /* Replace zero bytes by new values. */
+          for (;;)
+            {
+              int j, k;
+              unsigned char *pp;
+              
+              /* Count the zero bytes. */
+              for (j=k=0; j < i; j++)
+                {
+                  if (!p[j])
+                    k++;
+                }
+              if (!k)
+                break; /* Okay: no (more) zero bytes. */
+              
+              k += k/128; /* Better get some more. */
+              pp = gcry_random_bytes_secure (k, GCRY_STRONG_RANDOM);
+              for (j=0; j < i && k; j++)
+                {
+                  if (!p[j])
+                    p[j] = pp[--k];
+                }
+              gcry_free (pp);
+            }
+          memcpy (frame+n, p, i);
+          n += i;
+          gcry_free (p);
+          
+          frame[n++] = 0;
+          memcpy (frame+n, value, valuelen);
+          n += valuelen;
+          assert (n == nframe);
+
+	  /* FIXME, error checking?  */
+          gcry_mpi_scan (ret_mpi, GCRYMPI_FMT_USG, frame, n, &nframe);
+        }
+
+      gcry_free(frame);
+    }
+  else if (is_pkcs1 && lhash && !for_encryption)
+    { /* Create pkcs#1 block type 1 padding. */
+      if (gcry_sexp_length (lhash) != 3)
+        rc = GPG_ERR_INV_OBJ;
+      else if ( !(s=gcry_sexp_nth_data (lhash, 1, &n)) || !n )
+        rc = GPG_ERR_INV_OBJ;
+      else
+        {
+          static struct { const char *name; int algo; } hashnames[] = 
+          { { "sha1",   GCRY_MD_SHA1 },
+            { "md5",    GCRY_MD_MD5 },
+            { "rmd160", GCRY_MD_RMD160 },
+            { "sha256", GCRY_MD_SHA256 },
+            { "sha384", GCRY_MD_SHA384 },
+            { "sha512", GCRY_MD_SHA512 },
+            { "md2",    GCRY_MD_MD2 },
+            { "md4",    GCRY_MD_MD4 },
+            { "tiger",  GCRY_MD_TIGER },
+            { "haval",  GCRY_MD_HAVAL },
+            { NULL }
+          };
+          int algo;
+          byte asn[100];
+          byte *frame = NULL;
+          size_t nframe = (nbits+7) / 8;
+          const void * value;
+          size_t valuelen;
+          size_t asnlen, dlen;
+            
+          for (i=0; hashnames[i].name; i++)
+            {
+              if ( strlen (hashnames[i].name) == n
+                   && !memcmp (hashnames[i].name, s, n))
+                break;
+            }
+
+          algo = hashnames[i].algo;
+          asnlen = DIM(asn);
+          dlen = gcry_md_get_algo_dlen (algo);
+
+          if (!hashnames[i].name)
+            rc = GPG_ERR_DIGEST_ALGO;
+          else if ( !(value=gcry_sexp_nth_data (lhash, 2, &valuelen))
+                    || !valuelen )
+            rc = GPG_ERR_INV_OBJ;
+          else if (gcry_md_algo_info (algo, GCRYCTL_GET_ASNOID, asn, &asnlen))
+            {
+              /* We don't have yet all of the above algorithms.  */
+              rc = GPG_ERR_NOT_IMPLEMENTED;
+            }
+          else if ( valuelen != dlen )
+            {
+              /* Hash value does not match the length of digest for
+                 the given algorithm. */
+              rc = GPG_ERR_CONFLICT;
+            }
+          else if( !dlen || dlen + asnlen + 4 > nframe)
+            {
+              /* Can't encode an DLEN byte digest MD into a NFRAME
+                 byte frame. */
+              rc = GPG_ERR_TOO_SHORT;
+            }
+          else if ( !(frame = gcry_malloc (nframe)) )
+            rc = gpg_err_code_from_errno (errno);
+          else
+            { /* Assemble the pkcs#1 block type 1. */
+              n = 0;
+              frame[n++] = 0;
+              frame[n++] = 1; /* block type */
+              i = nframe - valuelen - asnlen - 3 ;
+              assert (i > 1);
+              memset (frame+n, 0xff, i );
+              n += i;
+              frame[n++] = 0;
+              memcpy (frame+n, asn, asnlen);
+              n += asnlen;
+              memcpy (frame+n, value, valuelen );
+              n += valuelen;
+              assert (n == nframe);
+      
+              /* convert it into an MPI, FIXME: error checking?  */
+              gcry_mpi_scan (ret_mpi, GCRYMPI_FMT_USG, frame, n, &nframe);
+            }
+          
+          gcry_free (frame);
+        }
+    }
+  else
+    rc = GPG_ERR_CONFLICT;
+   
+  gcry_sexp_release (ldata);
+  gcry_sexp_release (lhash);
+  gcry_sexp_release (lvalue);
+
+  if (!rc)
+    *flags = parsed_flags;
+
+  return rc;
+}
+
+
+/*
+   Do a PK encrypt operation
+  
+   Caller has to provide a public key as the SEXP pkey and data as a
+   SEXP with just one MPI in it. Alternativly S_DATA might be a
+   complex S-Expression, similar to the one used for signature
+   verification.  This provides a flag which allows to handle PKCS#1
+   block type 2 padding.  The function returns a a sexp which may be
+   passed to to pk_decrypt.
+  
+   Returns: 0 or an errorcode.
+  
+   s_data = See comment for sexp_data_to_mpi
+   s_pkey = <key-as-defined-in-sexp_to_key>
+   r_ciph = (enc-val
+               (<algo>
+                 (<param_name1> <mpi>)
+                 ...
+                 (<param_namen> <mpi>)
+               ))
+
+*/
+gcry_error_t
+gcry_pk_encrypt (gcry_sexp_t *r_ciph, gcry_sexp_t s_data, gcry_sexp_t s_pkey)
+{
+  gcry_mpi_t *pkey = NULL, data = NULL, *ciph = NULL;
+  const char *algo_name, *algo_elems;
+  int flags;
+  gcry_err_code_t rc;
+  gcry_pk_spec_t *pubkey = NULL;
+  gcry_module_t module = NULL;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  *r_ciph = NULL;
+  /* get the key */
+  rc = sexp_to_key (s_pkey, 0, &pkey, &module);
+  if (rc)
+    goto leave;
+
+  assert (module);
+  pubkey = (gcry_pk_spec_t *) module->spec;
+
+  /* If aliases for the algorithm name exists, take the first one
+     instead of the regular name to adhere to SPKI conventions.  We
+     assume that the first alias name is the lowercase version of the
+     regular one.  This change is required for compatibility with
+     1.1.12 generated S-expressions. */
+  algo_name = pubkey->aliases? *pubkey->aliases : NULL;
+  if (!algo_name || !*algo_name)
+    algo_name = pubkey->name;
+  
+  algo_elems = pubkey->elements_enc;
+  
+  /* Get the stuff we want to encrypt. */
+  rc = sexp_data_to_mpi (s_data, gcry_pk_get_nbits (s_pkey), &data, 1,
+                         &flags);
+  if (rc)
+    goto leave;
+
+  /* Now we can encrypt DATA to CIPH. */
+  ciph = gcry_xcalloc (strlen (algo_elems) + 1, sizeof (*ciph));
+  rc = pubkey_encrypt (module->mod_id, ciph, data, pkey, flags);
+  mpi_free (data);
+  data = NULL;
+  if (rc)
+    goto leave;
+
+  /* We did it.  Now build the return list */
+  {
+    char *string, *p;
+    int i;
+    size_t nelem = strlen (algo_elems);
+    size_t needed = 19 + strlen (algo_name) + (nelem * 5);
+    void **arg_list;
+    
+    /* Build the string.  */
+    string = p = gcry_xmalloc (needed);
+    p = stpcpy ( p, "(enc-val(" );
+    p = stpcpy ( p, algo_name );
+    for (i=0; algo_elems[i]; i++ )
+      {
+        *p++ = '(';
+        *p++ = algo_elems[i];
+        p = stpcpy ( p, "%m)" );
+      }
+    strcpy ( p, "))" );
+    
+    /* And now the ugly part: We don't have a function to pass an
+     * array to a format string, so we have to do it this way :-(.  */
+    /* FIXME: There is now such a format spefier, so we can could
+       change the code to be more clear. */
+    arg_list = malloc (nelem * sizeof *arg_list);
+    if (!arg_list)
+      {
+        rc = gpg_err_code_from_errno (errno);
+        goto leave;
+      }
+
+    for (i = 0; i < nelem; i++)
+      arg_list[i] = ciph + i;
+    
+    rc = gcry_sexp_build_array (r_ciph, NULL, string, arg_list);
+    free (arg_list);
+    if (rc)
+      BUG ();
+    gcry_free (string);
+  }
+
+ leave:
+  if (pkey)
+    {
+      release_mpi_array (pkey);
+      gcry_free (pkey);
+    }
+
+  if (ciph)
+    {
+      release_mpi_array (ciph);
+      gcry_free (ciph);
+    }
+
+  if (module)
+    {
+      ath_mutex_lock (&pubkeys_registered_lock);
+      _gcry_module_release (module);
+      ath_mutex_unlock (&pubkeys_registered_lock);
+    }
+
+  return gcry_error (rc);
+}
+
+/* 
+   Do a PK decrypt operation
+  
+   Caller has to provide a secret key as the SEXP skey and data in a
+   format as created by gcry_pk_encrypt.  For historic reasons the
+   function returns simply an MPI as an S-expression part; this is
+   deprecated and the new method should be used which returns a real
+   S-expressionl this is selected by adding at least an empty flags
+   list to S_DATA.
+   
+   Returns: 0 or an errorcode.
+  
+   s_data = (enc-val
+              [(flags)]
+              (<algo>
+                (<param_name1> <mpi>)
+                ...
+                (<param_namen> <mpi>)
+              ))
+   s_skey = <key-as-defined-in-sexp_to_key>
+   r_plain= Either an incomplete S-expression without the parentheses
+            or if the flags list is used (even if empty) a real S-expression:
+            (value PLAIN). 
+ */
+gcry_error_t
+gcry_pk_decrypt (gcry_sexp_t *r_plain, gcry_sexp_t s_data, gcry_sexp_t s_skey)
+{
+  gcry_mpi_t *skey = NULL, *data = NULL, plain = NULL;
+  int modern, want_pkcs1, flags;
+  gcry_err_code_t rc;
+  gcry_module_t module_enc = NULL, module_key = NULL;
+  gcry_pk_spec_t *pubkey = NULL;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  *r_plain = NULL;
+  rc = sexp_to_key (s_skey, 1, &skey, &module_key);
+  if (rc)
+    goto leave;
+
+  rc = sexp_to_enc (s_data, &data, &module_enc, &modern, &want_pkcs1, &flags);
+  if (rc)
+    goto leave;
+  
+  if (module_key->mod_id != module_enc->mod_id)
+    {
+      rc = GPG_ERR_CONFLICT; /* Key algo does not match data algo. */
+      goto leave;
+    }
+
+  pubkey = (gcry_pk_spec_t *) module_key->spec;
+
+  rc = pubkey_decrypt (module_key->mod_id, &plain, data, skey, flags);
+  if (rc)
+    goto leave;
+
+  if (gcry_sexp_build (r_plain, NULL, modern? "(value %m)" : "%m", plain))
+    BUG ();
+  
+ leave:
+  if (skey)
+    {
+      release_mpi_array (skey);
+      gcry_free (skey);
+    }
+
+  if (plain)
+    mpi_free (plain);
+
+  if (data)
+    {
+      release_mpi_array (data);
+      gcry_free (data);
+    }
+
+  if (module_key || module_enc)
+    {
+      ath_mutex_lock (&pubkeys_registered_lock);
+      if (module_key)
+	_gcry_module_release (module_key);
+      if (module_enc)
+	_gcry_module_release (module_enc);
+      ath_mutex_unlock (&pubkeys_registered_lock);
+    }
+
+  return gcry_error (rc);
+}
+
+
+
+/*
+   Create a signature.
+  
+   Caller has to provide a secret key as the SEXP skey and data
+   expressed as a SEXP list hash with only one element which should
+   instantly be available as a MPI. Alternatively the structure given
+   below may be used for S_HASH, it provides the abiliy to pass flags
+   to the operation; the only flag defined by now is "pkcs1" which
+   does PKCS#1 block type 1 style padding.
+  
+   Returns: 0 or an errorcode.
+            In case of 0 the function returns a new SEXP with the
+            signature value; the structure of this signature depends on the
+            other arguments but is always suitable to be passed to
+            gcry_pk_verify
+  
+   s_hash = See comment for sexp_data_to_mpi
+               
+   s_skey = <key-as-defined-in-sexp_to_key>
+   r_sig  = (sig-val
+              (<algo>
+                (<param_name1> <mpi>)
+                ...
+                (<param_namen> <mpi>))) 
+*/
+gcry_error_t
+gcry_pk_sign (gcry_sexp_t *r_sig, gcry_sexp_t s_hash, gcry_sexp_t s_skey)
+{
+  gcry_mpi_t *skey = NULL, hash = NULL, *result = NULL;
+  gcry_pk_spec_t *pubkey = NULL;
+  gcry_module_t module = NULL;
+  const char *algo_name, *algo_elems;
+  int i;
+  gcry_err_code_t rc;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  *r_sig = NULL;
+  rc = sexp_to_key (s_skey, 1, &skey, &module);
+  if (rc)
+    goto leave;
+
+  assert (module);
+  pubkey = (gcry_pk_spec_t *) module->spec;
+  algo_name = pubkey->aliases? *pubkey->aliases : NULL;
+  if (!algo_name || !*algo_name)
+    algo_name = pubkey->name;
+  
+  algo_elems = pubkey->elements_sig;
+
+  /* Get the stuff we want to sign.  Note that pk_get_nbits does also
+      work on a private key. */
+  rc = sexp_data_to_mpi (s_hash, gcry_pk_get_nbits (s_skey),
+                             &hash, 0, NULL);
+  if (rc)
+    goto leave;
+
+  result = gcry_xcalloc (strlen (algo_elems) + 1, sizeof (*result));
+  rc = pubkey_sign (module->mod_id, result, hash, skey);
+  if (rc)
+    goto leave;
+
+  {
+    char *string, *p;
+    size_t nelem, needed = strlen (algo_name) + 20;
+    void **arg_list;
+
+    nelem = strlen (algo_elems);
+    
+    /* Count elements, so that we can allocate enough space. */
+    needed += 10 * nelem;
+
+    /* Build the string. */
+    string = p = gcry_xmalloc (needed);
+    p = stpcpy (p, "(sig-val(");
+    p = stpcpy (p, algo_name);
+    for (i = 0; algo_elems[i]; i++)
+      {
+        *p++ = '(';
+        *p++ = algo_elems[i];
+        p = stpcpy (p, "%m)");
+      }
+    strcpy (p, "))");
+
+    arg_list = malloc (nelem * sizeof *arg_list);
+    if (!arg_list)
+      {
+        rc = gpg_err_code_from_errno (errno);
+        goto leave;
+      }
+
+    for (i = 0; i < nelem; i++)
+      arg_list[i] = result + i;
+
+    rc = gcry_sexp_build_array (r_sig, NULL, string, arg_list);
+    free (arg_list);
+    if (rc)
+      BUG ();
+    gcry_free (string);
+  }
+
+ leave:
+  if (skey)
+    {
+      release_mpi_array (skey);
+      gcry_free (skey);
+    }
+
+  if (hash)
+    mpi_free (hash);
+
+  if (result)
+    gcry_free (result);
+
+  return gcry_error (rc);
+}
+
+
+/*
+   Verify a signature.
+
+   Caller has to supply the public key pkey, the signature sig and his
+   hashvalue data.  Public key has to be a standard public key given
+   as an S-Exp, sig is a S-Exp as returned from gcry_pk_sign and data
+   must be an S-Exp like the one in sign too.  */
+gcry_error_t
+gcry_pk_verify (gcry_sexp_t s_sig, gcry_sexp_t s_hash, gcry_sexp_t s_pkey)
+{
+  gcry_module_t module_key = NULL, module_sig = NULL;
+  gcry_mpi_t *pkey = NULL, hash = NULL, *sig = NULL;
+  gcry_err_code_t rc;
+
+  REGISTER_DEFAULT_PUBKEYS;
+ 
+  rc = sexp_to_key (s_pkey, 0, &pkey, &module_key);
+  if (rc)
+    goto leave;
+
+  rc = sexp_to_sig (s_sig, &sig, &module_sig);
+  if (rc)
+    goto leave;
+
+  if (module_key->mod_id != module_sig->mod_id)
+    {
+      rc = GPG_ERR_CONFLICT;
+      goto leave;
+    }
+
+  rc = sexp_data_to_mpi (s_hash, gcry_pk_get_nbits (s_pkey), &hash, 0, 0);
+  if (rc)
+    goto leave;
+
+  rc = pubkey_verify (module_key->mod_id, hash, sig, pkey, NULL, NULL);
+
+ leave:
+  if (pkey)
+    {
+      release_mpi_array (pkey);
+      gcry_free (pkey);
+    }
+  if (sig)
+    {
+      release_mpi_array (sig);
+      gcry_free (sig);
+    }
+  if (hash)
+    mpi_free (hash);
+
+  if (module_key || module_sig)
+    {
+      ath_mutex_lock (&pubkeys_registered_lock);
+      if (module_key)
+	_gcry_module_release (module_key);
+      if (module_sig)
+	_gcry_module_release (module_sig);
+      ath_mutex_unlock (&pubkeys_registered_lock);
+    }
+
+  return gcry_error (rc);
+}
+
+
+/*
+   Test a key.
+
+   This may be used either for a public or a secret key to see whether
+   internal structre is valid.
+  
+   Returns: 0 or an errorcode.
+  
+   s_key = <key-as-defined-in-sexp_to_key> */
+gcry_error_t
+gcry_pk_testkey (gcry_sexp_t s_key)
+{
+  gcry_module_t module = NULL;
+  gcry_mpi_t *key = NULL;
+  gcry_err_code_t rc;
+  
+  REGISTER_DEFAULT_PUBKEYS;
+
+  /* Note we currently support only secret key checking. */
+  rc = sexp_to_key (s_key, 1, &key, &module);
+  if (! rc)
+    {
+      rc = pubkey_check_secret_key (module->mod_id, key);
+      release_mpi_array (key);
+      gcry_free (key);
+    }
+  return gcry_error (rc);
+}
+
+
+/*
+  Create a public key pair and return it in r_key.
+  How the key is created depends on s_parms:
+  (genkey
+   (algo
+     (parameter_name_1 ....)
+      ....
+     (parameter_name_n ....)
+  ))
+  The key is returned in a format depending on the
+  algorithm. Both, private and secret keys are returned
+  and optionally some additional informatin.
+  For elgamal we return this structure:
+  (key-data
+   (public-key
+     (elg
+ 	(p <mpi>)
+ 	(g <mpi>)
+ 	(y <mpi>)
+     )
+   )
+   (private-key
+     (elg
+ 	(p <mpi>)
+ 	(g <mpi>)
+ 	(y <mpi>)
+ 	(x <mpi>)
+     )
+   )
+   (misc-key-info
+      (pm1-factors n1 n2 ... nn)
+   ))
+ */
+gcry_error_t
+gcry_pk_genkey (gcry_sexp_t *r_key, gcry_sexp_t s_parms)
+{
+  gcry_pk_spec_t *pubkey = NULL;
+  gcry_module_t module = NULL;
+  gcry_sexp_t list = NULL, l2 = NULL;
+  const char *name;
+  size_t n;
+  gcry_err_code_t rc = GPG_ERR_NO_ERROR;
+  int i;
+  const char *algo_name = NULL;
+  int algo;
+  const char *sec_elems = NULL, *pub_elems = NULL;
+  gcry_mpi_t skey[10], *factors = NULL;
+  unsigned int nbits = 0;
+  unsigned long use_e = 0;
+  char *name_terminated;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  skey[0] = NULL;
+  *r_key = NULL;
+
+  list = gcry_sexp_find_token (s_parms, "genkey", 0);
+  if (!list)
+    {
+      rc = GPG_ERR_INV_OBJ; /* Does not contain genkey data. */
+      goto leave;
+    }
+
+  l2 = gcry_sexp_cadr (list);
+  gcry_sexp_release (list);
+  list = l2;
+  l2 = NULL;
+  if (! list)
+    {
+      rc = GPG_ERR_NO_OBJ; /* No cdr for the genkey. */
+      goto leave;
+    }
+
+  name = gcry_sexp_nth_data (list, 0, &n);
+  if (! name)
+    {
+      rc = GPG_ERR_INV_OBJ; /* Algo string missing. */
+      goto leave;
+    }
+
+  name_terminated = gcry_xmalloc (n + 1);
+  memcpy (name_terminated, name, n);
+  name_terminated[n] = 0;
+  ath_mutex_lock (&pubkeys_registered_lock);
+  module = gcry_pk_lookup_name (name_terminated);
+  ath_mutex_unlock (&pubkeys_registered_lock);
+  gcry_free (name_terminated);
+
+  if (! module)
+    {
+      rc = GPG_ERR_PUBKEY_ALGO; /* Unknown algorithm. */
+      goto leave;
+    }
+  
+  pubkey = (gcry_pk_spec_t *) module->spec;
+  algo = module->mod_id;
+  algo_name = pubkey->aliases? *pubkey->aliases : NULL;
+  if (!algo_name || !*algo_name)
+    algo_name = pubkey->name;
+  pub_elems = pubkey->elements_pkey;
+  sec_elems = pubkey->elements_skey;
+
+  /* Handle the optional rsa-use-e element. */
+  l2 = gcry_sexp_find_token (list, "rsa-use-e", 0);
+  if (l2)
+    {
+      char buf[50];
+
+      name = gcry_sexp_nth_data (l2, 1, &n);
+      if ((! name) || (n >= DIM (buf) - 1))
+        {
+          rc = GPG_ERR_INV_OBJ; /* No value or value too large. */
+          goto leave;
+        }
+      memcpy (buf, name, n);
+      buf[n] = 0;
+      use_e = strtoul (buf, NULL, 0);
+      gcry_sexp_release (l2);
+      l2 = NULL;
+    }
+  else
+    use_e = 65537; /* Not given, use the value generated by old versions. */
+
+  l2 = gcry_sexp_find_token (list, "nbits", 0);
+  gcry_sexp_release (list);
+  list = l2;
+  l2 = NULL;
+  
+  if (! list)
+    {
+      rc = GPG_ERR_NO_OBJ; /* No nbits parameter. */
+      goto leave;
+    }
+
+  name = gcry_sexp_nth_data (list, 1, &n);
+  if (! name)
+    {
+      rc = GPG_ERR_INV_OBJ; /* nbits without a cdr. */
+      goto leave;
+    }
+  
+  name_terminated = gcry_xmalloc (n + 1);
+  memcpy (name_terminated, name, n);
+  name_terminated[n] = 0;
+  nbits = (unsigned int) strtoul (name_terminated, NULL, 0);
+  gcry_free (name_terminated);
+
+  rc = pubkey_generate (module->mod_id, nbits, use_e, skey, &factors);
+  if (rc)
+    goto leave;
+
+  {
+    char *string, *p;
+    size_t nelem=0, nelem_cp = 0, needed=0;
+    gcry_mpi_t mpis[30];
+    
+    nelem = strlen (pub_elems) + strlen (sec_elems);
+    for (i = 0; factors[i]; i++)
+      nelem++;
+    nelem_cp = nelem;
+
+    needed += nelem * 10;
+    needed += 2 * strlen (algo_name) + 300;
+    if (nelem > DIM (mpis))
+      BUG ();
+
+    /* Build the string. */
+    nelem = 0;
+    string = p = gcry_xmalloc (needed);
+    p = stpcpy (p, "(key-data");
+    p = stpcpy (p, "(public-key(");
+    p = stpcpy (p, algo_name);
+    for(i = 0; pub_elems[i]; i++)
+      {
+        *p++ = '(';
+        *p++ = pub_elems[i];
+        p = stpcpy (p, "%m)");
+        mpis[nelem++] = skey[i];
+      }
+    p = stpcpy (p, "))");
+    p = stpcpy (p, "(private-key(");
+    p = stpcpy (p, algo_name);
+    for (i = 0; sec_elems[i]; i++)
+      {
+        *p++ = '(';
+        *p++ = sec_elems[i];
+        p = stpcpy (p, "%m)");
+        mpis[nelem++] = skey[i];
+      }
+    p = stpcpy (p, "))");
+
+    /* Very ugly hack to make release_mpi_array() work FIXME */
+    skey[i] = NULL;
+
+    p = stpcpy (p, "(misc-key-info(pm1-factors");
+    for(i = 0; factors[i]; i++)
+      {
+        p = stpcpy (p, "%m");
+        mpis[nelem++] = factors[i];
+      }
+    strcpy (p, ")))");
+
+    while (nelem < DIM (mpis))
+      mpis[nelem++] = NULL;
+
+    {
+      int elem_n = strlen (pub_elems) + strlen (sec_elems);
+      void **arg_list;
+
+      arg_list = malloc (nelem_cp * sizeof *arg_list);
+      if (!arg_list)
+        {
+          rc = gpg_err_code_from_errno (errno);
+          goto leave;
+        }
+      for (i = 0; i < elem_n; i++)
+        arg_list[i] = mpis + i;
+      for (; i < nelem_cp; i++)
+        arg_list[i] = factors + i - elem_n;
+      
+      rc = gcry_sexp_build_array (r_key, NULL, string, arg_list);
+      free (arg_list);
+      if (rc)
+	BUG ();
+      assert (DIM (mpis) == 30); /* Reminder to make sure that the
+                                    array gets increased if new
+                                    parameters are added. */
+    }
+    gcry_free (string);
+  }
+
+ leave:
+  release_mpi_array (skey);
+  /* Don't free SKEY itself, it is a static array. */
+    
+  if (factors)
+    {
+      release_mpi_array ( factors );
+      gcry_free (factors);
+    }
+  
+  if (l2)
+    gcry_sexp_release (l2);
+  if (list)
+    gcry_sexp_release (list);
+  
+  if (module)
+    {
+      ath_mutex_lock (&pubkeys_registered_lock);
+      _gcry_module_release (module);
+      ath_mutex_unlock (&pubkeys_registered_lock);
+    }
+
+  return gcry_error (rc);
+}
+
+
+/* 
+   Get the number of nbits from the public key.
+
+   Hmmm: Should we have really this function or is it better to have a
+   more general function to retrieve different propoerties of the key?  */
+unsigned int
+gcry_pk_get_nbits (gcry_sexp_t key)
+{
+  gcry_module_t module = NULL;
+  gcry_pk_spec_t *pubkey;
+  gcry_mpi_t *keyarr = NULL;
+  unsigned int nbits = 0;
+  gcry_err_code_t rc;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  rc = sexp_to_key (key, 0, &keyarr, &module);
+  if (rc == GPG_ERR_INV_OBJ)
+    rc = sexp_to_key (key, 1, &keyarr, &module);
+  if (rc)
+    return 0; /* Error - 0 is a suitable indication for that. */
+
+  pubkey = (gcry_pk_spec_t *) module->spec;
+  nbits = (*pubkey->get_nbits) (module->mod_id, keyarr);
+  
+  ath_mutex_lock (&pubkeys_registered_lock);
+  _gcry_module_release (module);
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  release_mpi_array (keyarr);
+  gcry_free (keyarr);
+
+  return nbits;
+}
+
+
+/* Return the so called KEYGRIP which is the SHA-1 hash of the public
+   key parameters expressed in a way depended on the algorithm.
+
+   ARRAY must either be 20 bytes long or NULL; in the latter case a
+   newly allocated array of that size is returned, otherwise ARRAY or
+   NULL is returned to indicate an error which is most likely an
+   unknown algorithm.  The function accepts public or secret keys. */
+unsigned char *
+gcry_pk_get_keygrip (gcry_sexp_t key, unsigned char *array)
+{
+  gcry_sexp_t list = NULL, l2 = NULL;
+  gcry_pk_spec_t *pubkey = NULL;
+  gcry_module_t module = NULL;
+  const char *s, *name;
+  size_t n;
+  int idx;
+  int is_rsa;
+  const char *elems;
+  gcry_md_hd_t md = NULL;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  /* Check that the first element is valid. */
+  list = gcry_sexp_find_token (key, "public-key", 0);
+  if (! list)
+    list = gcry_sexp_find_token (key, "private-key", 0);
+  if (! list)
+    list = gcry_sexp_find_token (key, "protected-private-key", 0);
+  if (! list)
+    return NULL; /* No public- or private-key object. */
+
+  l2 = gcry_sexp_cadr (list);
+  gcry_sexp_release (list);
+  list = l2;
+  l2 = NULL;
+
+  name = gcry_sexp_nth_data (list, 0, &n);
+  if (! name)
+    goto fail; /* Invalid structure of object. */
+
+  {
+    char *name_terminated = gcry_xmalloc (n + 1);
+    memcpy (name_terminated, name, n);
+    name_terminated[n] = 0;
+    ath_mutex_lock (&pubkeys_registered_lock);
+    module = gcry_pk_lookup_name (name_terminated);
+    ath_mutex_unlock (&pubkeys_registered_lock);
+    gcry_free (name_terminated);
+  }
+
+  if (! module)
+    goto fail; /* unknown algorithm */
+
+  pubkey = (gcry_pk_spec_t *) module->spec;
+
+  /* FIXME, special handling should be implemented by the algorithms,
+     not by the libgcrypt core.  */
+  is_rsa = module->mod_id == GCRY_PK_RSA;
+  elems = pubkey->elements_grip;
+  if (! elems)
+    goto fail; /* no grip parameter */
+    
+  if (gcry_md_open (&md, GCRY_MD_SHA1, 0))
+    goto fail;
+
+  for (idx = 0, s = elems; *s; s++, idx++)
+    {
+      const char *data;
+      size_t datalen;
+
+      l2 = gcry_sexp_find_token (list, s, 1);
+      if (! l2)
+        goto fail;
+      data = gcry_sexp_nth_data (l2, 1, &datalen);
+      if (! data)
+        goto fail;
+      if (!is_rsa)
+        {
+          char buf[30];
+
+          sprintf (buf, "(1:%c%u:", *s, (unsigned int)datalen);
+          gcry_md_write (md, buf, strlen (buf));
+        }
+  
+      /* PKCS-15 says that for RSA only the modulus should be hashed -
+         however, it is not clear wether this is meant to has the raw
+         bytes assuming this is an unsigned integer or whether the DER
+         required 0 should be prefixed. We hash the raw bytes.  For
+         non-RSA we hash S-expressions. */
+      gcry_md_write (md, data, datalen);
+      gcry_sexp_release (l2);
+      if (!is_rsa)
+        gcry_md_write (md, ")", 1);
+    }
+
+  if (!array)
+    {
+      array = gcry_malloc (20);
+      if (! array)
+        goto fail;
+    }
+
+  memcpy (array, gcry_md_read (md, GCRY_MD_SHA1), 20);
+  gcry_md_close (md);
+  gcry_sexp_release (list);
+  return array;
+
+ fail:
+  if (l2)
+    gcry_sexp_release (l2);
+  if (md)
+    gcry_md_close (md);
+  gcry_sexp_release (list);
+  return NULL;
+}
+
+
+gcry_error_t
+gcry_pk_ctl (int cmd, void *buffer, size_t buflen)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  switch (cmd)
+    {
+    case GCRYCTL_DISABLE_ALGO:
+      /* This one expects a buffer pointing to an integer with the
+         algo number.  */
+      if ((! buffer) || (buflen != sizeof (int)))
+	err = GPG_ERR_INV_ARG;
+      else
+	disable_pubkey_algo (*((int *) buffer));
+      break;
+
+    default:
+      err = GPG_ERR_INV_OP;
+    }
+
+  return gcry_error (err);
+}
+
+
+/*
+   Return information about the given algorithm
+   WHAT select the kind of information returned:
+    GCRYCTL_TEST_ALGO:
+        Returns 0 when the specified algorithm is available for use.
+        Buffer must be NULL, nbytes  may have the address of a variable
+        with the required usage of the algorithm. It may be 0 for don't
+        care or a combination of the GCRY_PK_USAGE_xxx flags;
+    GCRYCTL_GET_ALGO_USAGE:
+        Return the usage glafs for the give algo.  An invalid alog
+        does return 0.  Disabled algos are ignored here becuase we
+        only want to know whether the algo is at all capable of
+        the usage.
+  
+   Note: Because this function is in most cases used to return an
+   integer value, we can make it easier for the caller to just look at
+   the return value.  The caller will in all cases consult the value
+   and thereby detecting whether a error occured or not (i.e. while
+   checking the block size) */
+gcry_error_t
+gcry_pk_algo_info (int algorithm, int what, void *buffer, size_t *nbytes)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+
+  switch (what)
+    {
+    case GCRYCTL_TEST_ALGO:
+      {
+	int use = nbytes ? *nbytes : 0;
+	if (buffer)
+	  err = GPG_ERR_INV_ARG;
+	else if (check_pubkey_algo (algorithm, use))
+	  err = GPG_ERR_PUBKEY_ALGO;
+	break;
+      }
+
+    case GCRYCTL_GET_ALGO_USAGE:
+      {
+	gcry_module_t pubkey;
+	int use = 0;
+
+	REGISTER_DEFAULT_PUBKEYS;
+
+	ath_mutex_lock (&pubkeys_registered_lock);
+	pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+	if (pubkey)
+	  {
+	    use = ((gcry_pk_spec_t *) pubkey->spec)->use;
+	    _gcry_module_release (pubkey);
+	  }
+	ath_mutex_unlock (&pubkeys_registered_lock);
+
+	/* FIXME? */
+	*nbytes = use;
+      }
+
+    case GCRYCTL_GET_ALGO_NPKEY:
+      {
+	/* FIXME?  */
+	int npkey = pubkey_get_npkey (algorithm);
+	*nbytes = npkey;
+	break;
+      }
+    case GCRYCTL_GET_ALGO_NSKEY:
+      {
+	/* FIXME?  */
+	int nskey = pubkey_get_nskey (algorithm);
+	*nbytes = nskey;
+	break;
+      }
+    case GCRYCTL_GET_ALGO_NSIGN:
+      {
+	/* FIXME?  */
+	int nsign = pubkey_get_nsig (algorithm);
+	*nbytes = nsign;
+	break;
+      }
+    case GCRYCTL_GET_ALGO_NENCR:
+      {
+	/* FIXME?  */
+	int nencr = pubkey_get_nenc (algorithm);
+	*nbytes = nencr;
+	break;
+      }
+
+    default:
+      err = GPG_ERR_INV_OP;
+    }
+
+  return gcry_error (err);
+}
+
+
+gcry_err_code_t
+_gcry_pk_init (void)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  return err;
+}
+
+
+gcry_err_code_t
+_gcry_pk_module_lookup (int algorithm, gcry_module_t *module)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+  gcry_module_t pubkey;
+
+  REGISTER_DEFAULT_PUBKEYS;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  pubkey = _gcry_module_lookup_id (pubkeys_registered, algorithm);
+  if (pubkey)
+    *module = pubkey;
+  else
+    err = GPG_ERR_PUBKEY_ALGO;
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return err;
+}
+
+
+void
+_gcry_pk_module_release (gcry_module_t module)
+{
+  ath_mutex_lock (&pubkeys_registered_lock);
+  _gcry_module_release (module);
+  ath_mutex_unlock (&pubkeys_registered_lock);
+}
+
+/* Get a list consisting of the IDs of the loaded pubkey modules.  If
+   LIST is zero, write the number of loaded pubkey modules to
+   LIST_LENGTH and return.  If LIST is non-zero, the first
+   *LIST_LENGTH algorithm IDs are stored in LIST, which must be of
+   according size.  In case there are less pubkey modules than
+   *LIST_LENGTH, *LIST_LENGTH is updated to the correct number.  */
+gcry_error_t
+gcry_pk_list (int *list, int *list_length)
+{
+  gcry_err_code_t err = GPG_ERR_NO_ERROR;
+
+  ath_mutex_lock (&pubkeys_registered_lock);
+  err = _gcry_module_list (pubkeys_registered, list, list_length);
+  ath_mutex_unlock (&pubkeys_registered_lock);
+
+  return err;
+}