/*
- This file is part of GNUnet.
- (C) 2001, 2002, 2003, 2004, 2005, 2006 Christian Grothoff (and other contributing authors)
+ This file is part of GNUnet. Copyright (C) 2001-2014 Christian Grothoff
+ (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 2, or (at your
+ by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
*/
* @author Christian Grothoff
*/
#include "platform.h"
-#include "gnunet_common.h"
#include "gnunet_crypto_lib.h"
-#include "gnunet_os_lib.h"
#include <gcrypt.h>
+#define LOG(kind,...) GNUNET_log_from (kind, "util-crypto-random", __VA_ARGS__)
+
+#define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util-crypto-random", syscall)
+
+
+/* TODO: ndurner, move this to plibc? */
+/* The code is derived from glibc, obviously */
+#if !HAVE_RANDOM || !HAVE_SRANDOM
+#ifdef RANDOM
+#undef RANDOM
+#endif
+#ifdef SRANDOM
+#undef SRANDOM
+#endif
+#define RANDOM() glibc_weak_rand32()
+#define SRANDOM(s) glibc_weak_srand32(s)
+#if defined(RAND_MAX)
+#undef RAND_MAX
+#endif
+#define RAND_MAX 0x7fffffff /* Hopefully this is correct */
+
+
+static int32_t glibc_weak_rand32_state = 1;
+
+
+void
+glibc_weak_srand32 (int32_t s)
+{
+ glibc_weak_rand32_state = s;
+}
+
+
+int32_t
+glibc_weak_rand32 ()
+{
+ int32_t val = glibc_weak_rand32_state;
+
+ val = ((glibc_weak_rand32_state * 1103515245) + 12345) & 0x7fffffff;
+ glibc_weak_rand32_state = val;
+ return val;
+}
+#endif
+
/**
* Create a cryptographically weak pseudo-random number in the interval of 0 to 1.
- *
+ *
* @return number between 0 and 1.
*/
static double
-weak_random ()
+get_weak_random ()
{
return ((double) RANDOM () / RAND_MAX);
}
/**
- * Produce a random value.
+ * Seed a weak random generator. Only #GNUNET_CRYPTO_QUALITY_WEAK-mode generator
+ * can be seeded.
+ *
+ * @param seed the seed to use
+ */
+void
+GNUNET_CRYPTO_seed_weak_random (int32_t seed)
+{
+ SRANDOM (seed);
+}
+
+
+/**
+ * @ingroup crypto
+ * Fill block with a random values.
+ *
+ * @param mode desired quality of the random number
+ * @param buffer the buffer to fill
+ * @param length buffer length
+ */
+void
+GNUNET_CRYPTO_random_block (enum GNUNET_CRYPTO_Quality mode, void *buffer, size_t length)
+{
+#ifdef gcry_fast_random_poll
+ static unsigned int invokeCount;
+#endif
+ switch (mode)
+ {
+ case GNUNET_CRYPTO_QUALITY_STRONG:
+ /* see http://lists.gnupg.org/pipermail/gcrypt-devel/2004-May/000613.html */
+#ifdef gcry_fast_random_poll
+ if ((invokeCount++ % 256) == 0)
+ gcry_fast_random_poll ();
+#endif
+ gcry_randomize (buffer, length, GCRY_STRONG_RANDOM);
+ return;
+ case GNUNET_CRYPTO_QUALITY_NONCE:
+ gcry_create_nonce (buffer, length);
+ return;
+ case GNUNET_CRYPTO_QUALITY_WEAK:
+ /* see http://lists.gnupg.org/pipermail/gcrypt-devel/2004-May/000613.html */
+#ifdef gcry_fast_random_poll
+ if ((invokeCount++ % 256) == 0)
+ gcry_fast_random_poll ();
+#endif
+ gcry_randomize (buffer, length, GCRY_WEAK_RANDOM);
+ return;
+ default:
+ GNUNET_assert (0);
+ }
+}
+
+
+/**
+ * Produce a random unsigned 32-bit number modulo @a i.
*
* @param mode desired quality of the random number
* @param i the upper limit (exclusive) for the random number
* @return a random value in the interval [0,i[.
*/
uint32_t
-GNUNET_CRYPTO_random_u32 (enum GNUNET_CRYPTO_Quality mode, uint32_t i)
+GNUNET_CRYPTO_random_u32 (enum GNUNET_CRYPTO_Quality mode,
+ uint32_t i)
{
#ifdef gcry_fast_random_poll
static unsigned int invokeCount;
GNUNET_assert (i > 0);
switch (mode)
- {
- case GNUNET_CRYPTO_QUALITY_STRONG:
- /* see http://lists.gnupg.org/pipermail/gcrypt-devel/2004-May/000613.html */
+ {
+ case GNUNET_CRYPTO_QUALITY_STRONG:
+ /* see http://lists.gnupg.org/pipermail/gcrypt-devel/2004-May/000613.html */
#ifdef gcry_fast_random_poll
- if ((invokeCount++ % 256) == 0)
- gcry_fast_random_poll ();
+ if ((invokeCount++ % 256) == 0)
+ gcry_fast_random_poll ();
#endif
- ul = UINT32_MAX - (UINT32_MAX % i);
- do
- {
- gcry_randomize ((unsigned char *) &ret,
- sizeof (uint32_t), GCRY_STRONG_RANDOM);
- }
- while (ret >= ul);
- return ret % i;
- case GNUNET_CRYPTO_QUALITY_NONCE:
- ul = UINT32_MAX - (UINT32_MAX % i);
- do
- {
- gcry_create_nonce(&ret, sizeof(ret));
- }
- while (ret >= ul);
- return ret % i;
- case GNUNET_CRYPTO_QUALITY_WEAK:
- ret = i * weak_random ();
- if (ret >= i)
- ret = i - 1;
- return ret;
- default:
- GNUNET_assert (0);
+ ul = UINT32_MAX - (UINT32_MAX % i);
+ do
+ {
+ gcry_randomize ((unsigned char *) &ret, sizeof (uint32_t),
+ GCRY_STRONG_RANDOM);
+ }
+ while (ret >= ul);
+ return ret % i;
+ case GNUNET_CRYPTO_QUALITY_NONCE:
+ ul = UINT32_MAX - (UINT32_MAX % i);
+ do
+ {
+ gcry_create_nonce (&ret, sizeof (ret));
}
+ while (ret >= ul);
+ return ret % i;
+ case GNUNET_CRYPTO_QUALITY_WEAK:
+ ret = i * get_weak_random ();
+ if (ret >= i)
+ ret = i - 1;
+ return ret;
+ default:
+ GNUNET_assert (0);
+ }
return 0;
}
/**
* Get an array with a random permutation of the
* numbers 0...n-1.
- * @param mode GNUNET_RANDOM_QUALITY_STRONG if the strong (but expensive)
- * PRNG should be used, GNUNET_RANDOM_QUALITY_WEAK otherwise
+ * @param mode #GNUNET_RANDOM_QUALITY_STRONG if the strong (but expensive)
+ * PRNG should be used, #GNUNET_RANDOM_QUALITY_WEAK otherwise
* @param n the size of the array
* @return the permutation array (allocated from heap)
*/
unsigned int *
-GNUNET_CRYPTO_random_permute (enum GNUNET_CRYPTO_Quality mode, unsigned int n)
+GNUNET_CRYPTO_random_permute (enum GNUNET_CRYPTO_Quality mode,
+ unsigned int n)
{
unsigned int *ret;
unsigned int i;
for (i = 0; i < n; i++)
ret[i] = i;
for (i = n - 1; i > 0; i--)
- {
- x = GNUNET_CRYPTO_random_u32 (mode, i+1);
- tmp = ret[x];
- ret[x] = ret[i];
- ret[i] = tmp;
- }
+ {
+ x = GNUNET_CRYPTO_random_u32 (mode, i + 1);
+ tmp = ret[x];
+ ret[x] = ret[i];
+ ret[i] = tmp;
+ }
return ret;
}
+
/**
- * Random on unsigned 64-bit values.
- *
+ * Generate random unsigned 64-bit value.
*
* @param mode desired quality of the random number
* @param max value returned will be in range [0,max) (exclusive)
GNUNET_assert (max > 0);
switch (mode)
+ {
+ case GNUNET_CRYPTO_QUALITY_STRONG:
+ ul = UINT64_MAX - (UINT64_MAX % max);
+ do
{
- case GNUNET_CRYPTO_QUALITY_STRONG:
- ul = UINT64_MAX - (UINT64_MAX % max);
- do
- {
- gcry_randomize ((unsigned char *) &ret,
- sizeof (uint64_t), GCRY_STRONG_RANDOM);
- }
- while (ret >= ul);
- return ret % max;
- case GNUNET_CRYPTO_QUALITY_NONCE:
- ul = UINT64_MAX - (UINT64_MAX % max);
- do
- {
- gcry_create_nonce(&ret, sizeof(ret));
- }
- while (ret >= ul);
-
- return ret % max;
- case GNUNET_CRYPTO_QUALITY_WEAK:
- ret = max * weak_random ();
- if (ret >= max)
- ret = max - 1;
- return ret;
- default:
- GNUNET_assert (0);
+ gcry_randomize ((unsigned char *) &ret, sizeof (uint64_t),
+ GCRY_STRONG_RANDOM);
}
- return 0;
-}
+ while (ret >= ul);
+ return ret % max;
+ case GNUNET_CRYPTO_QUALITY_NONCE:
+ ul = UINT64_MAX - (UINT64_MAX % max);
+ do
+ {
+ gcry_create_nonce (&ret, sizeof (ret));
+ }
+ while (ret >= ul);
-/**
- * This function should only be called in testcases
- * where strong entropy gathering is not desired
- * (for example, for hostkey generation).
- */
-void
-GNUNET_CRYPTO_random_disable_entropy_gathering ()
-{
- gcry_control (GCRYCTL_ENABLE_QUICK_RANDOM, 0);
+ return ret % max;
+ case GNUNET_CRYPTO_QUALITY_WEAK:
+ ret = max * get_weak_random ();
+ if (ret >= max)
+ ret = max - 1;
+ return ret;
+ default:
+ GNUNET_assert (0);
+ }
+ return 0;
}
/**
- * Process ID of the "find" process that we use for
- * entropy gathering.
- */
-static struct GNUNET_OS_Process *genproc;
-
-/**
- * Function called by libgcrypt whenever we are
- * blocked gathering entropy.
+ * Initialize libgcrypt.
*/
-static void
-entropy_generator (void *cls,
- const char *what, int printchar, int current, int total)
+void __attribute__ ((constructor))
+GNUNET_CRYPTO_random_init ()
{
- unsigned long code;
- enum GNUNET_OS_ProcessStatusType type;
- int ret;
+ gcry_error_t rc;
- if (0 != strcmp (what, "need_entropy"))
- return;
- if (current == total)
- {
- if (genproc != NULL)
- {
- if (0 != GNUNET_OS_process_kill (genproc, SIGTERM))
- GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "kill");
- GNUNET_break (GNUNET_OK == GNUNET_OS_process_wait (genproc));
- GNUNET_OS_process_close (genproc);
- genproc = NULL;
- }
- return;
- }
- if (genproc != NULL)
- {
- ret = GNUNET_OS_process_status (genproc, &type, &code);
- if (ret == GNUNET_NO)
- return; /* still running */
- if (ret == GNUNET_SYSERR)
- {
- GNUNET_break (0);
- return;
- }
- if (0 != GNUNET_OS_process_kill (genproc, SIGTERM))
- GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "kill");
- GNUNET_break (GNUNET_OK == GNUNET_OS_process_wait (genproc));
- GNUNET_OS_process_close (genproc);
- genproc = NULL;
- }
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- _("Starting `%s' process to generate entropy\n"), "find");
- genproc = GNUNET_OS_start_process (NULL, NULL, "sh",
- "sh",
- "-c",
- "exec find / -mount -type f -exec cp {} /dev/null \\; 2>/dev/null",
- NULL);
-}
-
-
-static void
-killfind ()
-{
- if (genproc != NULL)
- {
- GNUNET_OS_process_kill (genproc, SIGKILL);
- GNUNET_OS_process_close (genproc);
- genproc = NULL;
- }
-}
-
-
-void __attribute__ ((constructor)) GNUNET_CRYPTO_random_init ()
-{
- SRANDOM (time (NULL));
- gcry_control (GCRYCTL_DISABLE_SECMEM, 0);
- if (!gcry_check_version (GCRYPT_VERSION))
- {
- fprintf (stderr,
- _
- ("libgcrypt has not the expected version (version %s is required).\n"),
- GCRYPT_VERSION);
- abort ();
- }
-#ifdef gcry_fast_random_poll
+ if (! gcry_check_version (NEED_LIBGCRYPT_VERSION))
+ {
+ FPRINTF (stderr,
+ _("libgcrypt has not the expected version (version %s is required).\n"),
+ NEED_LIBGCRYPT_VERSION);
+ GNUNET_assert (0);
+ }
+ if ((rc = gcry_control (GCRYCTL_DISABLE_SECMEM, 0)))
+ FPRINTF (stderr,
+ "Failed to set libgcrypt option %s: %s\n",
+ "DISABLE_SECMEM",
+ gcry_strerror (rc));
+ /* Otherwise gnunet-ecc takes forever to complete, besides
+ we are fine with "just" using GCRY_STRONG_RANDOM */
+ if ((rc = gcry_control (GCRYCTL_ENABLE_QUICK_RANDOM, 0)))
+ FPRINTF (stderr,
+ "Failed to set libgcrypt option %s: %s\n",
+ "ENABLE_QUICK_RANDOM",
+ gcry_strerror (rc));
+ gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
gcry_fast_random_poll ();
-#endif
- gcry_set_progress_handler (&entropy_generator, NULL);
- atexit (&killfind);
+ GNUNET_CRYPTO_seed_weak_random (time (NULL) ^
+ GNUNET_CRYPTO_random_u32
+ (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX));
}
-void __attribute__ ((destructor)) GNUNET_CRYPTO_random_fini ()
+/**
+ * Nicely shut down libgcrypt.
+ */
+void __attribute__ ((destructor))
+GNUNET_CRYPTO_random_fini ()
{
gcry_set_progress_handler (NULL, NULL);
+#ifdef GCRYCTL_CLOSE_RANDOM_DEVICE
+ (void) gcry_control (GCRYCTL_CLOSE_RANDOM_DEVICE, 0);
+#endif
}
/* end of crypto_random.c */
-
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