libgcrypt-sys 0.6.1

/* global.c  -	global control functions
 * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003
 *               2004, 2005, 2006, 2008, 2011,
 *               2012  Free Software Foundation, Inc.
 * Copyright (C) 2013, 2014, 2017 g10 Code GmbH
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include <config.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <ctype.h>
#include <limits.h>
#include <errno.h>
#include <unistd.h>
#ifdef HAVE_SYSLOG
# include <syslog.h>
#endif /*HAVE_SYSLOG*/

#include "g10lib.h"
#include "gcrypt-testapi.h"
#include "cipher.h"
#include "stdmem.h" /* our own memory allocator */
#include "secmem.h" /* our own secmem allocator */




/****************
 * flag bits: 0 : general cipher debug
 *	      1 : general MPI debug
 */
static unsigned int debug_flags;

/* gcry_control (GCRYCTL_SET_FIPS_MODE), sets this flag so that the
   initialization code switched fips mode on.  */
static int force_fips_mode;

/* Controlled by global_init().  */
static int any_init_done;

/*
 * Functions called before and after blocking syscalls.
 * Initialized by global_init and used via
 * _gcry_pre_syscall and _gcry_post_syscall.
 */
static void (*pre_syscall_func)(void);
static void (*post_syscall_func)(void);


/* Memory management. */

static gcry_handler_alloc_t alloc_func;
static gcry_handler_alloc_t alloc_secure_func;
static gcry_handler_secure_check_t is_secure_func;
static gcry_handler_realloc_t realloc_func;
static gcry_handler_free_t free_func;
static gcry_handler_no_mem_t outofcore_handler;
static void *outofcore_handler_value;
static int no_secure_memory;

/* Prototypes.  */
static gpg_err_code_t external_lock_test (int cmd);




/* This is our handmade constructor.  It gets called by any function
   likely to be called at startup.  The suggested way for an
   application to make sure that this has been called is by using
   gcry_check_version. */
static void
global_init (void)
{
  gcry_error_t err = 0;

  if (any_init_done)
    return;
  any_init_done = 1;

  /* Tell the random module that we have seen an init call.  */
  _gcry_set_preferred_rng_type (0);

  /* Get the system call clamp functions.  */
  if (!pre_syscall_func)
    gpgrt_get_syscall_clamp (&pre_syscall_func, &post_syscall_func);

  /* See whether the system is in FIPS mode.  This needs to come as
     early as possible but after ATH has been initialized.  */
  _gcry_initialize_fips_mode (force_fips_mode);

  /* Before we do any other initialization we need to test available
     hardware features.  */
  _gcry_detect_hw_features ();

  /* Initialize the modules - this is mainly allocating some memory and
     creating mutexes.  */
  err = _gcry_cipher_init ();
  if (err)
    goto fail;
  err = _gcry_md_init ();
  if (err)
    goto fail;
  err = _gcry_mac_init ();
  if (err)
    goto fail;
  err = _gcry_pk_init ();
  if (err)
    goto fail;
  err = _gcry_primegen_init ();
  if (err)
    goto fail;
  err = _gcry_secmem_module_init ();
  if (err)
    goto fail;
  err = _gcry_mpi_init ();
  if (err)
    goto fail;

  return;

 fail:
  BUG ();
}


/* This function is called by the macro fips_is_operational and makes
   sure that the minimal initialization has been done.  This is far
   from a perfect solution and hides problems with an improper
   initialization but at least in single-threaded mode it should work
   reliable.

   The reason we need this is that a lot of applications don't use
   Libgcrypt properly by not running any initialization code at all.
   They just call a Libgcrypt function and that is all what they want.
   Now with the FIPS mode, that has the side effect of entering FIPS
   mode (for security reasons, FIPS mode is the default if no
   initialization has been done) and bailing out immediately because
   the FSM is in the wrong state.  If we always run the init code,
   Libgcrypt can test for FIPS mode and at least if not in FIPS mode,
   it will behave as before.  Note that this on-the-fly initialization
   is only done for the cryptographic functions subject to FIPS mode
   and thus not all API calls will do such an initialization.  */
int
_gcry_global_is_operational (void)
{
  if (!any_init_done)
    {
#ifdef HAVE_SYSLOG
      syslog (LOG_USER|LOG_WARNING, "Libgcrypt warning: "
              "missing initialization - please fix the application");
#endif /*HAVE_SYSLOG*/
      global_init ();
    }
  return _gcry_fips_is_operational ();
}




/* Version number parsing.  */

/* This function parses the first portion of the version number S and
   stores it in *NUMBER.  On success, this function returns a pointer
   into S starting with the first character, which is not part of the
   initial number portion; on failure, NULL is returned.  */
static const char*
parse_version_number( const char *s, int *number )
{
    int val = 0;

    if( *s == '0' && isdigit(s[1]) )
	return NULL; /* leading zeros are not allowed */
    for ( ; isdigit(*s); s++ ) {
	val *= 10;
	val += *s - '0';
    }
    *number = val;
    return val < 0? NULL : s;
}

/* This function breaks up the complete string-representation of the
   version number S, which is of the following struture: <major
   number>.<minor number>.<micro number><patch level>.  The major,
   minor and micro number components will be stored in *MAJOR, *MINOR
   and *MICRO.

   On success, the last component, the patch level, will be returned;
   in failure, NULL will be returned.  */

static const char *
parse_version_string( const char *s, int *major, int *minor, int *micro )
{
    s = parse_version_number( s, major );
    if( !s || *s != '.' )
	return NULL;
    s++;
    s = parse_version_number( s, minor );
    if( !s || *s != '.' )
	return NULL;
    s++;
    s = parse_version_number( s, micro );
    if( !s )
	return NULL;
    return s; /* patchlevel */
}

/* If REQ_VERSION is non-NULL, check that the version of the library
   is at minimum the requested one.  Returns the string representation
   of the library version if the condition is satisfied; return NULL
   if the requested version is newer than that of the library.

   If a NULL is passed to this function, no check is done, but the
   string representation of the library is simply returned.  */
const char *
_gcry_check_version (const char *req_version)
{
    const char *ver = VERSION;
    int my_major, my_minor, my_micro;
    int rq_major, rq_minor, rq_micro;
    const char *my_plvl;

    if (req_version && req_version[0] == 1 && req_version[1] == 1)
        return _gcry_compat_identification ();

    /* Initialize library.  */
    global_init ();

    if ( !req_version )
        /* Caller wants our version number.  */
	return ver;

    /* Parse own version number.  */
    my_plvl = parse_version_string( ver, &my_major, &my_minor, &my_micro );
    if ( !my_plvl )
        /* very strange our own version is bogus.  Shouldn't we use
	   assert() here and bail out in case this happens?  -mo.  */
	return NULL;

    /* Parse requested version number.  */
    if (!parse_version_string (req_version, &rq_major, &rq_minor, &rq_micro))
      return NULL;  /* req version string is invalid, this can happen.  */

    /* Compare version numbers.  */
    if ( my_major > rq_major
	|| (my_major == rq_major && my_minor > rq_minor)
	|| (my_major == rq_major && my_minor == rq_minor		                           		 && my_micro > rq_micro)
	|| (my_major == rq_major && my_minor == rq_minor
                                 && my_micro == rq_micro))
      {
	return ver;
      }

    return NULL;
}


static void
print_config (const char *what, gpgrt_stream_t fp)
{
  int i;
  const char *s;

  if (!what || !strcmp (what, "version"))
    {
      gpgrt_fprintf (fp, "version:%s:%x:%s:%x:\n",
                     VERSION, GCRYPT_VERSION_NUMBER,
                     GPGRT_VERSION, GPGRT_VERSION_NUMBER);
    }
  if (!what || !strcmp (what, "cc"))
    {
      gpgrt_fprintf (fp, "cc:%d:%s:\n",
#if GPGRT_VERSION_NUMBER >= 0x011b00 /* 1.27 */
                     GPGRT_GCC_VERSION
#else
                     _GPG_ERR_GCC_VERSION /* Due to a bug in gpg-error.h.  */
#endif
                     ,
#ifdef __clang__
                     "clang:" __VERSION__
#elif __GNUC__
                     "gcc:" __VERSION__
#else
                     ":"
#endif
                     );
    }

  if (!what || !strcmp (what, "ciphers"))
    gpgrt_fprintf (fp, "ciphers:%s:\n", LIBGCRYPT_CIPHERS);
  if (!what || !strcmp (what, "pubkeys"))
    gpgrt_fprintf (fp, "pubkeys:%s:\n", LIBGCRYPT_PUBKEY_CIPHERS);
  if (!what || !strcmp (what, "digests"))
    gpgrt_fprintf (fp, "digests:%s:\n", LIBGCRYPT_DIGESTS);

  if (!what || !strcmp (what, "rnd-mod"))
    {
      gpgrt_fprintf (fp, "rnd-mod:"
#if USE_RNDEGD
                     "egd:"
#endif
#if USE_RNDLINUX
                     "linux:"
#endif
#if USE_RNDUNIX
                     "unix:"
#endif
#if USE_RNDW32
                     "w32:"
#endif
                     "\n");
    }

  if (!what || !strcmp (what, "cpu-arch"))
    {
      gpgrt_fprintf (fp, "cpu-arch:"
#if defined(HAVE_CPU_ARCH_X86)
                     "x86"
#elif defined(HAVE_CPU_ARCH_ALPHA)
                     "alpha"
#elif defined(HAVE_CPU_ARCH_SPARC)
                     "sparc"
#elif defined(HAVE_CPU_ARCH_MIPS)
                     "mips"
#elif defined(HAVE_CPU_ARCH_M68K)
                     "m68k"
#elif defined(HAVE_CPU_ARCH_PPC)
                     "ppc"
#elif defined(HAVE_CPU_ARCH_ARM)
                     "arm"
#endif
                     ":\n");
    }

  if (!what || !strcmp (what, "mpi-asm"))
    gpgrt_fprintf (fp, "mpi-asm:%s:\n", _gcry_mpi_get_hw_config ());

  if (!what || !strcmp (what, "hwflist"))
    {
      unsigned int hwfeatures, afeature;

      hwfeatures = _gcry_get_hw_features ();
      gpgrt_fprintf (fp, "hwflist:");
      for (i=0; (s = _gcry_enum_hw_features (i, &afeature)); i++)
        if ((hwfeatures & afeature))
          gpgrt_fprintf (fp, "%s:", s);
      gpgrt_fprintf (fp, "\n");
    }

  if (!what || !strcmp (what, "fips-mode"))
    {
      /* We use y/n instead of 1/0 for the stupid reason that
       * Emacsen's compile error parser would accidentally flag that
       * line when printed during "make check" as an error.  */
      gpgrt_fprintf (fp, "fips-mode:%c:%c:\n",
                     fips_mode ()? 'y':'n',
                     _gcry_enforced_fips_mode ()? 'y':'n' );
    }

  if (!what || !strcmp (what, "rng-type"))
    {
      /* The currently used RNG type.  */
      unsigned int jver;
      int active;

      i = _gcry_get_rng_type (0);
      switch (i)
        {
        case GCRY_RNG_TYPE_STANDARD: s = "standard"; break;
        case GCRY_RNG_TYPE_FIPS:     s = "fips"; break;
        case GCRY_RNG_TYPE_SYSTEM:   s = "system"; break;
        default: BUG ();
        }
      jver = _gcry_rndjent_get_version (&active);
      gpgrt_fprintf (fp, "rng-type:%s:%d:%u:%d:\n", s, i, jver, active);
    }
}


/* With a MODE of 0 return a malloced string with configured features.
 * In that case a WHAT of NULL returns everything in the same way
 * GCRYCTL_PRINT_CONFIG would do.  With a specific WHAT string only
 * the requested feature is returned (w/o the trailing LF.  On error
 * NULL is returned.  */
char *
_gcry_get_config (int mode, const char *what)
{
  gpgrt_stream_t fp;
  int save_errno;
  void *data;
  char *p;

  if (mode)
    {
      gpg_err_set_errno (EINVAL);
      return NULL;
    }

  fp = gpgrt_fopenmem (0, "w+b,samethread");
  if (!fp)
    return NULL;

  print_config (what, fp);
  if (gpgrt_ferror (fp))
    {
      save_errno = errno;
      gpgrt_fclose (fp);
      gpg_err_set_errno (save_errno);
      return NULL;
    }

  gpgrt_rewind (fp);
  if (gpgrt_fclose_snatch (fp, &data, NULL))
    {
      save_errno = errno;
      gpgrt_fclose (fp);
      gpg_err_set_errno (save_errno);
      return NULL;
    }

  if (!data)
    {
      /* Nothing was printed (unknown value for WHAT).  This is okay,
       * so clear ERRNO to indicate this. */
      gpg_err_set_errno (0);
      return NULL;
    }

  /* Strip trailing LF.  */
  if (what && (p = strchr (data, '\n')))
    *p = 0;

  return data;
}




/* Command dispatcher function, acting as general control
   function.  */
gcry_err_code_t
_gcry_vcontrol (enum gcry_ctl_cmds cmd, va_list arg_ptr)
{
  static int init_finished = 0;
  gcry_err_code_t rc = 0;

  switch (cmd)
    {
    case GCRYCTL_ENABLE_M_GUARD:
      _gcry_private_enable_m_guard ();
      break;

    case GCRYCTL_ENABLE_QUICK_RANDOM:
      _gcry_set_preferred_rng_type (0);
      _gcry_enable_quick_random_gen ();
      break;

    case GCRYCTL_FAKED_RANDOM_P:
      /* Return an error if the RNG is faked one (e.g. enabled by
         ENABLE_QUICK_RANDOM. */
      if (_gcry_random_is_faked ())
        rc = GPG_ERR_GENERAL;  /* Use as TRUE value.  */
      break;

    case GCRYCTL_DUMP_RANDOM_STATS:
      _gcry_random_dump_stats ();
      break;

    case GCRYCTL_DUMP_MEMORY_STATS:
      /*m_print_stats("[fixme: prefix]");*/
      break;

    case GCRYCTL_DUMP_SECMEM_STATS:
      _gcry_secmem_dump_stats (0);
      break;

    case GCRYCTL_DROP_PRIVS:
      global_init ();
      _gcry_secmem_init (0);
      break;

    case GCRYCTL_DISABLE_SECMEM:
      global_init ();
      no_secure_memory = 1;
      break;

    case GCRYCTL_INIT_SECMEM:
      global_init ();
      _gcry_secmem_init (va_arg (arg_ptr, unsigned int));
      if ((_gcry_secmem_get_flags () & GCRY_SECMEM_FLAG_NOT_LOCKED))
        rc = GPG_ERR_GENERAL;
      break;

    case GCRYCTL_TERM_SECMEM:
      global_init ();
      _gcry_secmem_term ();
      break;

    case GCRYCTL_DISABLE_SECMEM_WARN:
      _gcry_set_preferred_rng_type (0);
      _gcry_secmem_set_flags ((_gcry_secmem_get_flags ()
			       | GCRY_SECMEM_FLAG_NO_WARNING));
      break;

    case GCRYCTL_SUSPEND_SECMEM_WARN:
      _gcry_set_preferred_rng_type (0);
      _gcry_secmem_set_flags ((_gcry_secmem_get_flags ()
			       | GCRY_SECMEM_FLAG_SUSPEND_WARNING));
      break;

    case GCRYCTL_RESUME_SECMEM_WARN:
      _gcry_set_preferred_rng_type (0);
      _gcry_secmem_set_flags ((_gcry_secmem_get_flags ()
			       & ~GCRY_SECMEM_FLAG_SUSPEND_WARNING));
      break;

    case 78: /* GCRYCTL_AUTO_EXPAND_SECMEM (backport from 1.9) */
      _gcry_secmem_set_auto_expand (va_arg (arg_ptr, unsigned int));
      break;

    case GCRYCTL_USE_SECURE_RNDPOOL:
      global_init ();
      _gcry_secure_random_alloc (); /* Put random number into secure memory. */
      break;

    case GCRYCTL_SET_RANDOM_SEED_FILE:
      _gcry_set_preferred_rng_type (0);
      _gcry_set_random_seed_file (va_arg (arg_ptr, const char *));
      break;

    case GCRYCTL_UPDATE_RANDOM_SEED_FILE:
      _gcry_set_preferred_rng_type (0);
      if ( fips_is_operational () )
        _gcry_update_random_seed_file ();
      break;

    case GCRYCTL_SET_VERBOSITY:
      _gcry_set_preferred_rng_type (0);
      _gcry_set_log_verbosity (va_arg (arg_ptr, int));
      break;

    case GCRYCTL_SET_DEBUG_FLAGS:
      debug_flags |= va_arg (arg_ptr, unsigned int);
      break;

    case GCRYCTL_CLEAR_DEBUG_FLAGS:
      debug_flags &= ~va_arg (arg_ptr, unsigned int);
      break;

    case GCRYCTL_DISABLE_INTERNAL_LOCKING:
      /* Not used anymore.  */
      global_init ();
      break;

    case GCRYCTL_ANY_INITIALIZATION_P:
      if (any_init_done)
	rc = GPG_ERR_GENERAL;
      break;

    case GCRYCTL_INITIALIZATION_FINISHED_P:
      if (init_finished)
	rc = GPG_ERR_GENERAL; /* Yes.  */
      break;

    case GCRYCTL_INITIALIZATION_FINISHED:
      /* This is a hook which should be used by an application after
	 all initialization has been done and right before any threads
	 are started.  It is not really needed but the only way to be
	 really sure that all initialization for thread-safety has
	 been done. */
      if (! init_finished)
        {
          global_init ();
          /* Do only a basic random initialization, i.e. init the
             mutexes. */
          _gcry_random_initialize (0);
          init_finished = 1;
          /* Force us into operational state if in FIPS mode.  */
          (void)fips_is_operational ();
        }
      break;

    case GCRYCTL_SET_THREAD_CBS:
      /* This is now a dummy call.  We used to install our own thread
         library here. */
      _gcry_set_preferred_rng_type (0);
      global_init ();
      break;

    case GCRYCTL_FAST_POLL:
      _gcry_set_preferred_rng_type (0);
      /* We need to do make sure that the random pool is really
         initialized so that the poll function is not a NOP. */
      _gcry_random_initialize (1);

      if ( fips_is_operational () )
        _gcry_fast_random_poll ();
      break;

    case GCRYCTL_SET_RNDEGD_SOCKET:
#if USE_RNDEGD
      _gcry_set_preferred_rng_type (0);
      rc = _gcry_rndegd_set_socket_name (va_arg (arg_ptr, const char *));
#else
      rc = GPG_ERR_NOT_SUPPORTED;
#endif
      break;

    case GCRYCTL_SET_RANDOM_DAEMON_SOCKET:
      _gcry_set_preferred_rng_type (0);
      _gcry_set_random_daemon_socket (va_arg (arg_ptr, const char *));
      break;

    case GCRYCTL_USE_RANDOM_DAEMON:
      /* We need to do make sure that the random pool is really
         initialized so that the poll function is not a NOP. */
      _gcry_set_preferred_rng_type (0);
      _gcry_random_initialize (1);
      _gcry_use_random_daemon (!! va_arg (arg_ptr, int));
      break;

    case GCRYCTL_CLOSE_RANDOM_DEVICE:
      _gcry_random_close_fds ();
      break;

      /* This command dumps information pertaining to the
         configuration of libgcrypt to the given stream.  It may be
         used before the initialization has been finished but not
         before a gcry_version_check.  See also gcry_get_config.  */
    case GCRYCTL_PRINT_CONFIG:
      {
        FILE *fp = va_arg (arg_ptr, FILE *);
        char *tmpstr;
        _gcry_set_preferred_rng_type (0);
        tmpstr = _gcry_get_config (0, NULL);
        if (tmpstr)
          {
            if (fp)
              fputs (tmpstr, fp);
            else
              log_info ("%s", tmpstr);
            xfree (tmpstr);
          }
      }
      break;

    case GCRYCTL_OPERATIONAL_P:
      /* Returns true if the library is in an operational state.  This
         is always true for non-fips mode.  */
      _gcry_set_preferred_rng_type (0);
      if (_gcry_fips_test_operational ())
        rc = GPG_ERR_GENERAL; /* Used as TRUE value */
      break;

    case GCRYCTL_FIPS_MODE_P:
      if (fips_mode ()
          && !_gcry_is_fips_mode_inactive ()
          && !no_secure_memory)
	rc = GPG_ERR_GENERAL; /* Used as TRUE value */
      break;

    case GCRYCTL_FORCE_FIPS_MODE:
      /* Performing this command puts the library into fips mode.  If
         the library has already been initialized into fips mode, a
         selftest is triggered.  It is not possible to put the libraty
         into fips mode after having passed the initialization. */
      _gcry_set_preferred_rng_type (0);
      if (!any_init_done)
        {
          /* Not yet initialized at all.  Set a flag so that we are put
             into fips mode during initialization.  */
          force_fips_mode = 1;
        }
      else
        {
          /* Already initialized.  If we are already operational we
             run a selftest.  If not we use the is_operational call to
             force us into operational state if possible.  */
          if (_gcry_fips_test_error_or_operational ())
            _gcry_fips_run_selftests (1);
          if (_gcry_fips_is_operational ())
            rc = GPG_ERR_GENERAL; /* Used as TRUE value */
      }
      break;

    case GCRYCTL_SELFTEST:
      /* Run a selftest.  This works in fips mode as well as in
         standard mode.  In contrast to the power-up tests, we use an
         extended version of the selftests. Returns 0 on success or an
         error code. */
      global_init ();
      rc = _gcry_fips_run_selftests (1);
      break;

#if _GCRY_GCC_VERSION >= 40600
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wswitch"
#endif
    case PRIV_CTL_INIT_EXTRNG_TEST:  /* Init external random test.  */
      rc = GPG_ERR_NOT_SUPPORTED;
      break;
    case PRIV_CTL_RUN_EXTRNG_TEST:  /* Run external DRBG test.  */
      {
        struct gcry_drbg_test_vector *test =
	  va_arg (arg_ptr, struct gcry_drbg_test_vector *);
        unsigned char *buf = va_arg (arg_ptr, unsigned char *);

        if (buf)
          rc = _gcry_rngdrbg_cavs_test (test, buf);
        else
          rc = _gcry_rngdrbg_healthcheck_one (test);
      }
      break;
    case PRIV_CTL_DEINIT_EXTRNG_TEST:  /* Deinit external random test.  */
      rc = GPG_ERR_NOT_SUPPORTED;
      break;
    case PRIV_CTL_EXTERNAL_LOCK_TEST:  /* Run external lock test */
      rc = external_lock_test (va_arg (arg_ptr, int));
      break;
    case PRIV_CTL_DUMP_SECMEM_STATS:
      _gcry_secmem_dump_stats (1);
      break;
#if _GCRY_GCC_VERSION >= 40600
# pragma GCC diagnostic pop
#endif

    case GCRYCTL_DISABLE_HWF:
      {
        const char *name = va_arg (arg_ptr, const char *);
        rc = _gcry_disable_hw_feature (name);
      }
      break;

    case GCRYCTL_SET_ENFORCED_FIPS_FLAG:
      if (!any_init_done)
        {
          /* Not yet initialized at all.  Set the enforced fips mode flag */
          _gcry_set_preferred_rng_type (0);
          _gcry_set_enforced_fips_mode ();
        }
      else
        rc = GPG_ERR_GENERAL;
      break;

    case GCRYCTL_SET_PREFERRED_RNG_TYPE:
      /* This may be called before gcry_check_version.  */
      {
        int i = va_arg (arg_ptr, int);
        /* Note that we may not pass 0 to _gcry_set_preferred_rng_type.  */
        if (i > 0)
          _gcry_set_preferred_rng_type (i);
      }
      break;

    case GCRYCTL_GET_CURRENT_RNG_TYPE:
      {
        int *ip = va_arg (arg_ptr, int*);
        if (ip)
          *ip = _gcry_get_rng_type (!any_init_done);
      }
      break;

    case GCRYCTL_DISABLE_LOCKED_SECMEM:
      _gcry_set_preferred_rng_type (0);
      _gcry_secmem_set_flags ((_gcry_secmem_get_flags ()
			       | GCRY_SECMEM_FLAG_NO_MLOCK));
      break;

    case GCRYCTL_DISABLE_PRIV_DROP:
      _gcry_set_preferred_rng_type (0);
      _gcry_secmem_set_flags ((_gcry_secmem_get_flags ()
			       | GCRY_SECMEM_FLAG_NO_PRIV_DROP));
      break;

    case GCRYCTL_INACTIVATE_FIPS_FLAG:
    case GCRYCTL_REACTIVATE_FIPS_FLAG:
      rc = GPG_ERR_NOT_IMPLEMENTED;
      break;

    case GCRYCTL_DRBG_REINIT:
      {
        const char *flagstr = va_arg (arg_ptr, const char *);
        gcry_buffer_t *pers = va_arg (arg_ptr, gcry_buffer_t *);
        int npers = va_arg (arg_ptr, int);
        if (va_arg (arg_ptr, void *) || npers < 0)
          rc = GPG_ERR_INV_ARG;
        else if (_gcry_get_rng_type (!any_init_done) != GCRY_RNG_TYPE_FIPS)
          rc = GPG_ERR_NOT_SUPPORTED;
        else
          rc = _gcry_rngdrbg_reinit (flagstr, pers, npers);
      }
      break;

    case GCRYCTL_REINIT_SYSCALL_CLAMP:
      if (!pre_syscall_func)
        gpgrt_get_syscall_clamp (&pre_syscall_func, &post_syscall_func);
      break;

    default:
      _gcry_set_preferred_rng_type (0);
      rc = GPG_ERR_INV_OP;
    }

  return rc;
}



/* Set custom allocation handlers.  This is in general not useful
 * because the libgcrypt allocation functions are guaranteed to
 * provide proper allocation handlers which zeroize memory if needed.
 * NOTE: All 5 functions should be set.  */
void
_gcry_set_allocation_handler (gcry_handler_alloc_t new_alloc_func,
                              gcry_handler_alloc_t new_alloc_secure_func,
                              gcry_handler_secure_check_t new_is_secure_func,
                              gcry_handler_realloc_t new_realloc_func,
                              gcry_handler_free_t new_free_func)
{
  global_init ();

  if (fips_mode ())
    {
      /* We do not want to enforce the fips mode, but merely set a
         flag so that the application may check whether it is still in
         fips mode.  */
      _gcry_inactivate_fips_mode ("custom allocation handler");
    }

  alloc_func = new_alloc_func;
  alloc_secure_func = new_alloc_secure_func;
  is_secure_func = new_is_secure_func;
  realloc_func = new_realloc_func;
  free_func = new_free_func;
}



/****************
 * Set an optional handler which is called in case the xmalloc functions
 * ran out of memory.  This handler may do one of these things:
 *   o free some memory and return true, so that the xmalloc function
 *     tries again.
 *   o Do whatever it like and return false, so that the xmalloc functions
 *     use the default fatal error handler.
 *   o Terminate the program and don't return.
 *
 * The handler function is called with 3 arguments:  The opaque value set with
 * this function, the requested memory size, and a flag with these bits
 * currently defined:
 *	bit 0 set = secure memory has been requested.
 */
void
_gcry_set_outofcore_handler (int (*f)(void*, size_t, unsigned int), void *value)
{
  global_init ();

  if (fips_mode () )
    {
      log_info ("out of core handler ignored in FIPS mode\n");
      return;
    }

  outofcore_handler = f;
  outofcore_handler_value = value;
}

/* Return the no_secure_memory flag.  */
static int
get_no_secure_memory (void)
{
  if (!no_secure_memory)
    return 0;
  if (_gcry_enforced_fips_mode ())
    {
      no_secure_memory = 0;
      return 0;
    }
  return no_secure_memory;
}


static gcry_err_code_t
do_malloc (size_t n, unsigned int flags, void **mem)
{
  gcry_err_code_t err = 0;
  void *m;

  if ((flags & GCRY_ALLOC_FLAG_SECURE) && !get_no_secure_memory ())
    {
      if (alloc_secure_func)
	m = (*alloc_secure_func) (n);
      else
	m = _gcry_private_malloc_secure (n, !!(flags & GCRY_ALLOC_FLAG_XHINT));
    }
  else
    {
      if (alloc_func)
	m = (*alloc_func) (n);
      else
	m = _gcry_private_malloc (n);
    }

  if (!m)
    {
      /* Make sure that ERRNO has been set in case a user supplied
         memory handler didn't it correctly. */
      if (!errno)
        gpg_err_set_errno (ENOMEM);
      err = gpg_err_code_from_errno (errno);
    }
  else
    *mem = m;

  return err;
}

void *
_gcry_malloc (size_t n)
{
  void *mem = NULL;

  do_malloc (n, 0, &mem);

  return mem;
}

static void *
_gcry_malloc_secure_core (size_t n, int xhint)
{
  void *mem = NULL;

  do_malloc (n, (GCRY_ALLOC_FLAG_SECURE | (xhint? GCRY_ALLOC_FLAG_XHINT:0)),
             &mem);

  return mem;
}

void *
_gcry_malloc_secure (size_t n)
{
  return _gcry_malloc_secure_core (n, 0);
}

int
_gcry_is_secure (const void *a)
{
  if (get_no_secure_memory ())
    return 0;
  if (is_secure_func)
    return is_secure_func (a) ;
  return _gcry_private_is_secure (a);
}

void
_gcry_check_heap( const void *a )
{
  (void)a;

    /* FIXME: implement this*/
#if 0
    if( some_handler )
	some_handler(a)
    else
	_gcry_private_check_heap(a)
#endif
}

static void *
_gcry_realloc_core (void *a, size_t n, int xhint)
{
  void *p;

  /* To avoid problems with non-standard realloc implementations and
     our own secmem_realloc, we divert to malloc and free here.  */
  if (!a)
    return _gcry_malloc (n);
  if (!n)
    {
      xfree (a);
      return NULL;
    }

  if (realloc_func)
    p = realloc_func (a, n);
  else
    p =  _gcry_private_realloc (a, n, xhint);
  if (!p && !errno)
    gpg_err_set_errno (ENOMEM);
  return p;
}


void *
_gcry_realloc (void *a, size_t n)
{
  return _gcry_realloc_core (a, n, 0);
}


void
_gcry_free (void *p)
{
  int save_errno;

  if (!p)
    return;

  /* In case ERRNO is set we better save it so that the free machinery
     may not accidentally change ERRNO.  We restore it only if it was
     already set to comply with the usual C semantic for ERRNO.  */
  save_errno = errno;
  if (free_func)
    free_func (p);
  else
    _gcry_private_free (p);

  if (save_errno)
    gpg_err_set_errno (save_errno);
}

void *
_gcry_calloc (size_t n, size_t m)
{
  size_t bytes;
  void *p;

  bytes = n * m; /* size_t is unsigned so the behavior on overflow is
                    defined. */
  if (m && bytes / m != n)
    {
      gpg_err_set_errno (ENOMEM);
      return NULL;
    }

  p = _gcry_malloc (bytes);
  if (p)
    memset (p, 0, bytes);
  return p;
}

void *
_gcry_calloc_secure (size_t n, size_t m)
{
  size_t bytes;
  void *p;

  bytes = n * m; /* size_t is unsigned so the behavior on overflow is
                    defined. */
  if (m && bytes / m != n)
    {
      gpg_err_set_errno (ENOMEM);
      return NULL;
    }

  p = _gcry_malloc_secure (bytes);
  if (p)
    memset (p, 0, bytes);
  return p;
}


static char *
_gcry_strdup_core (const char *string, int xhint)
{
  char *string_cp = NULL;
  size_t string_n = 0;

  string_n = strlen (string);

  if (_gcry_is_secure (string))
    string_cp = _gcry_malloc_secure_core (string_n + 1, xhint);
  else
    string_cp = _gcry_malloc (string_n + 1);

  if (string_cp)
    strcpy (string_cp, string);

  return string_cp;
}

/* Create and return a copy of the null-terminated string STRING.  If
 * it is contained in secure memory, the copy will be contained in
 * secure memory as well.  In an out-of-memory condition, NULL is
 * returned.  */
char *
_gcry_strdup (const char *string)
{
  return _gcry_strdup_core (string, 0);
}

void *
_gcry_xmalloc( size_t n )
{
  void *p;

  while ( !(p = _gcry_malloc( n )) )
    {
      if ( fips_mode ()
           || !outofcore_handler
           || !outofcore_handler (outofcore_handler_value, n, 0) )
        {
          _gcry_fatal_error (gpg_err_code_from_errno (errno), NULL);
        }
    }
    return p;
}

void *
_gcry_xrealloc( void *a, size_t n )
{
  void *p;

  while (!(p = _gcry_realloc_core (a, n, 1)))
    {
      if ( fips_mode ()
           || !outofcore_handler
           || !outofcore_handler (outofcore_handler_value, n,
                                  _gcry_is_secure(a)? 3:2))
        {
          _gcry_fatal_error (gpg_err_code_from_errno (errno), NULL );
	}
    }
    return p;
}

void *
_gcry_xmalloc_secure( size_t n )
{
  void *p;

  while (!(p = _gcry_malloc_secure_core (n, 1)))
    {
      if ( fips_mode ()
           || !outofcore_handler
           || !outofcore_handler (outofcore_handler_value, n, 1) )
        {
          _gcry_fatal_error (gpg_err_code_from_errno (errno),
                             _("out of core in secure memory"));
	}
    }
  return p;
}


void *
_gcry_xcalloc( size_t n, size_t m )
{
  size_t nbytes;
  void *p;

  nbytes = n * m;
  if (m && nbytes / m != n)
    {
      gpg_err_set_errno (ENOMEM);
      _gcry_fatal_error(gpg_err_code_from_errno (errno), NULL );
    }

  p = _gcry_xmalloc ( nbytes );
  memset ( p, 0, nbytes );
  return p;
}

void *
_gcry_xcalloc_secure( size_t n, size_t m )
{
  size_t nbytes;
  void *p;

  nbytes = n * m;
  if (m && nbytes / m != n)
    {
      gpg_err_set_errno (ENOMEM);
      _gcry_fatal_error(gpg_err_code_from_errno (errno), NULL );
    }

  p = _gcry_xmalloc_secure ( nbytes );
  memset ( p, 0, nbytes );
  return p;
}

char *
_gcry_xstrdup (const char *string)
{
  char *p;

  while ( !(p = _gcry_strdup_core (string, 1)) )
    {
      size_t n = strlen (string);
      int is_sec = !!_gcry_is_secure (string);

      if (fips_mode ()
          || !outofcore_handler
          || !outofcore_handler (outofcore_handler_value, n, is_sec) )
        {
          _gcry_fatal_error (gpg_err_code_from_errno (errno),
                             is_sec? _("out of core in secure memory"):NULL);
	}
    }

  return p;
}


/* Used before blocking system calls.  */
void
_gcry_pre_syscall (void)
{
  if (pre_syscall_func)
    pre_syscall_func ();
}


/* Used after blocking system calls.  */
void
_gcry_post_syscall (void)
{
  if (post_syscall_func)
    post_syscall_func ();
}


int
_gcry_get_debug_flag (unsigned int mask)
{
  if ( fips_mode () )
    return 0;
  return (debug_flags & mask);
}



/* It is often useful to get some feedback of long running operations.
   This function may be used to register a handler for this.
   The callback function CB is used as:

   void cb (void *opaque, const char *what, int printchar,
           int current, int total);

   Where WHAT is a string identifying the the type of the progress
   output, PRINTCHAR the character usually printed, CURRENT the amount
   of progress currently done and TOTAL the expected amount of
   progress.  A value of 0 for TOTAL indicates that there is no
   estimation available.

   Defined values for WHAT:

   "need_entropy"  X    0  number-of-bytes-required
            When running low on entropy
   "primegen"      '\n'  0 0
           Prime generated
                   '!'
           Need to refresh the prime pool
                   '<','>'
           Number of bits adjusted
                   '^'
           Looking for a generator
                   '.'
           Fermat tests on 10 candidates failed
                  ':'
           Restart with a new random value
                  '+'
           Rabin Miller test passed
   "pk_elg"        '+','-','.','\n'   0  0
            Only used in debugging mode.
   "pk_dsa"
            Only used in debugging mode.
*/
void
_gcry_set_progress_handler (void (*cb)(void *,const char*,int, int, int),
                            void *cb_data)
{
#if USE_DSA
  _gcry_register_pk_dsa_progress (cb, cb_data);
#endif
#if USE_ELGAMAL
  _gcry_register_pk_elg_progress (cb, cb_data);
#endif
  _gcry_register_primegen_progress (cb, cb_data);
  _gcry_register_random_progress (cb, cb_data);
}



/* This is a helper for the regression test suite to test Libgcrypt's locks.
   It works using a one test lock with CMD controlling what to do:

     30111 - Allocate and init lock
     30112 - Take lock
     30113 - Release lock
     30114 - Destroy lock.

   This function is used by tests/t-lock.c - it is not part of the
   public API!
 */
static gpg_err_code_t
external_lock_test (int cmd)
{
  GPGRT_LOCK_DEFINE (testlock);
  gpg_err_code_t rc = 0;

  switch (cmd)
    {
    case 30111:  /* Init Lock.  */
      rc = gpgrt_lock_init (&testlock);
      break;

    case 30112:  /* Take Lock.  */
      rc = gpgrt_lock_lock (&testlock);
      break;

    case 30113:  /* Release Lock.  */
      rc = gpgrt_lock_unlock (&testlock);
      break;

    case 30114:  /* Destroy Lock.  */
      rc = gpgrt_lock_destroy (&testlock);
      break;

    default:
      rc = GPG_ERR_INV_OP;
      break;
    }

  return rc;
}