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/*
This file is part of GNUnet.
(C) 2003, 2004, 2005, 2006 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 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*/
/**
* @author Krista Bennett
* @author Christian Grothoff
* @file util/test_crypto_aes_weak.c
* @brief AES weak key test.
*/
#include "platform.h"
#include "gnunet_common.h"
#include "gnunet_crypto_lib.h"
#include <gcrypt.h>
#define MAX_WEAK_KEY_TRIALS 100000
#define GENERATE_WEAK_KEYS GNUNET_NO
#define WEAK_KEY_TESTSTRING "I hate weak keys."
static void
printWeakKey (struct GNUNET_CRYPTO_AesSessionKey *key)
{
int i;
for (i = 0; i < GNUNET_CRYPTO_AES_KEY_LENGTH; i++)
{
printf ("%x ", (int) (key->key[i]));
}
}
static int
testWeakKey ()
{
char result[100];
char res[100];
int size;
struct GNUNET_CRYPTO_AesSessionKey weak_key;
struct GNUNET_CRYPTO_AesInitializationVector INITVALUE;
memset (&INITVALUE, 42,
sizeof (struct GNUNET_CRYPTO_AesInitializationVector));
/* sorry, this is not a weak key -- I don't have
* any at the moment! */
weak_key.key[0] = (char) (0x4c);
weak_key.key[1] = (char) (0x31);
weak_key.key[2] = (char) (0xc6);
weak_key.key[3] = (char) (0x2b);
weak_key.key[4] = (char) (0xc1);
weak_key.key[5] = (char) (0x5f);
weak_key.key[6] = (char) (0x4d);
weak_key.key[7] = (char) (0x1f);
weak_key.key[8] = (char) (0x31);
weak_key.key[9] = (char) (0xaa);
weak_key.key[10] = (char) (0x12);
weak_key.key[11] = (char) (0x2e);
weak_key.key[12] = (char) (0xb7);
weak_key.key[13] = (char) (0x82);
weak_key.key[14] = (char) (0xc0);
weak_key.key[15] = (char) (0xb6);
weak_key.key[16] = (char) (0x4d);
weak_key.key[17] = (char) (0x1f);
weak_key.key[18] = (char) (0x31);
weak_key.key[19] = (char) (0xaa);
weak_key.key[20] = (char) (0x4c);
weak_key.key[21] = (char) (0x31);
weak_key.key[22] = (char) (0xc6);
weak_key.key[23] = (char) (0x2b);
weak_key.key[24] = (char) (0xc1);
weak_key.key[25] = (char) (0x5f);
weak_key.key[26] = (char) (0x4d);
weak_key.key[27] = (char) (0x1f);
weak_key.key[28] = (char) (0x31);
weak_key.key[29] = (char) (0xaa);
weak_key.key[30] = (char) (0xaa);
weak_key.key[31] = (char) (0xaa);
/* memset(&weak_key, 0, 32); */
weak_key.crc32 =
htonl (GNUNET_CRYPTO_crc32_n (&weak_key, GNUNET_CRYPTO_AES_KEY_LENGTH));
size =
GNUNET_CRYPTO_aes_encrypt (WEAK_KEY_TESTSTRING,
strlen (WEAK_KEY_TESTSTRING) + 1, &weak_key,
&INITVALUE, result);
if (size == -1)
{
GNUNET_break (0);
return 1;
}
size = GNUNET_CRYPTO_aes_decrypt (result, size, &weak_key, &INITVALUE, res);
if ((strlen (WEAK_KEY_TESTSTRING) + 1) != size)
{
GNUNET_break (0);
return 1;
}
if (0 != strcmp (res, WEAK_KEY_TESTSTRING))
{
GNUNET_break (0);
return 1;
}
else
return 0;
}
static int
getWeakKeys ()
{
struct GNUNET_CRYPTO_AesSessionKey sessionkey;
int number_of_weak_keys = 0;
int number_of_runs;
gcry_cipher_hd_t handle;
int rc;
for (number_of_runs = 0; number_of_runs < MAX_WEAK_KEY_TRIALS;
number_of_runs++)
{
if (number_of_runs % 1000 == 0)
FPRINTF (stderr, "%s", ".");
/*printf("Got to run number %d.\n", number_of_runs); */
GNUNET_CRYPTO_aes_create_session_key (&sessionkey);
rc = gcry_cipher_open (&handle, GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_CFB,
0);
if (rc)
{
printf ("testweakkey: gcry_cipher_open failed on trial %d. %s\n",
number_of_runs, gcry_strerror (rc));
continue;
}
rc = gcry_cipher_setkey (handle, &sessionkey, GNUNET_CRYPTO_AES_KEY_LENGTH);
if ((char) rc == GPG_ERR_WEAK_KEY)
{
printf ("\nWeak key (in hex): ");
printWeakKey (&sessionkey);
printf ("\n");
number_of_weak_keys++;
}
else if (rc)
{
printf ("\nUnexpected error generating keys. Error is %s\n",
gcry_strerror (rc));
}
gcry_cipher_close (handle);
}
return number_of_weak_keys;
}
int
main (int argc, char *argv[])
{
int weak_keys;
GNUNET_log_setup ("test-crypto-aes-weak", "WARNING", NULL);
GNUNET_CRYPTO_random_disable_entropy_gathering ();
if (GENERATE_WEAK_KEYS)
{
weak_keys = getWeakKeys ();
if (weak_keys == 0)
{
printf ("\nNo weak keys found in %d runs.\n", MAX_WEAK_KEY_TRIALS);
}
else
{
printf ("\n%d weak keys found in %d runs.\n", weak_keys,
MAX_WEAK_KEY_TRIALS);
}
}
if (testWeakKey () != 0)
return -1;
return 0;
}
/* end of weakkeytest.c */
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