/*
This file is part of GNUnet.
- (C) 2001, 2002, 2003, 2004, 2005, 2006 Christian Grothoff (and other contributing authors)
+ (C) 2001, 2002, 2003, 2004, 2005, 2006, 2012 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
#include "gnunet_os_lib.h"
#include <gcrypt.h>
+#define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
+
+#define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util", syscall)
+
+
+/**
+ * GNUNET_YES if we are using a 'weak' (low-entropy) PRNG.
+ */
+static int weak_random;
+
+
+
+/* TODO: ndurner, move this to plibc? */
+/* The code is derived from glibc, obviously */
+#if MINGW
+#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);
}
+/**
+ * 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);
+}
+
+
/**
* Produce a random value.
*
while (ret >= ul);
return ret % i;
case GNUNET_CRYPTO_QUALITY_WEAK:
- ret = i * weak_random ();
+ ret = i * get_weak_random ();
if (ret >= i)
ret = i - 1;
return ret;
return ret % max;
case GNUNET_CRYPTO_QUALITY_WEAK:
- ret = max * weak_random ();
+ ret = max * get_weak_random ();
if (ret >= max)
ret = max - 1;
return ret;
return 0;
}
+
+/**
+ * Check if we are using weak random number generation.
+ *
+ * @return GNUNET_YES if weak number generation is on
+ */
+int
+GNUNET_CRYPTO_random_is_weak ()
+{
+ return weak_random;
+}
+
+
/**
* This function should only be called in testcases
* where strong entropy gathering is not desired
void
GNUNET_CRYPTO_random_disable_entropy_gathering ()
{
+ weak_random = GNUNET_YES;
gcry_control (GCRYCTL_ENABLE_QUICK_RANDOM, 0);
}
*/
static struct GNUNET_OS_Process *genproc;
+
/**
* Function called by libgcrypt whenever we are
* blocked gathering entropy.
if (genproc != NULL)
{
if (0 != GNUNET_OS_process_kill (genproc, SIGTERM))
- GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "kill");
+ LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "kill");
GNUNET_break (GNUNET_OK == GNUNET_OS_process_wait (genproc));
- GNUNET_OS_process_close (genproc);
+ GNUNET_OS_process_destroy (genproc);
genproc = NULL;
}
return;
return;
}
if (0 != GNUNET_OS_process_kill (genproc, SIGTERM))
- GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "kill");
+ LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "kill");
GNUNET_break (GNUNET_OK == GNUNET_OS_process_wait (genproc));
- GNUNET_OS_process_close (genproc);
+ GNUNET_OS_process_destroy (genproc);
genproc = NULL;
}
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- _("Starting `%s' process to generate entropy\n"), "find");
+ 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);
+ GNUNET_OS_start_process (GNUNET_NO, 0,
+ NULL, NULL, "sh", "sh", "-c",
+ "exec find / -mount -type f -exec cp {} /dev/null \\; 2>/dev/null",
+ NULL);
}
if (genproc != NULL)
{
GNUNET_OS_process_kill (genproc, SIGKILL);
- GNUNET_OS_process_close (genproc);
+ GNUNET_OS_process_destroy (genproc);
genproc = NULL;
}
}
void __attribute__ ((constructor)) GNUNET_CRYPTO_random_init ()
{
gcry_control (GCRYCTL_DISABLE_SECMEM, 0);
- if (!gcry_check_version (GCRYPT_VERSION))
+ if (!gcry_check_version (NEED_LIBGCRYPT_VERSION))
{
- fprintf (stderr,
+ FPRINTF (stderr,
_
("libgcrypt has not the expected version (version %s is required).\n"),
- GCRYPT_VERSION);
- abort ();
+ NEED_LIBGCRYPT_VERSION);
+ GNUNET_abort ();
}
+#ifdef GCRYCTL_INITIALIZATION_FINISHED
+ gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
+#endif
#ifdef gcry_fast_random_poll
gcry_fast_random_poll ();
#endif
gcry_set_progress_handler (&entropy_generator, NULL);
atexit (&killfind);
- SRANDOM (time (NULL) ^
- GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX));
+ GNUNET_CRYPTO_seed_weak_random (time (NULL) ^
+ GNUNET_CRYPTO_random_u32
+ (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX));
}