view libtomcrypt/testprof/dsa_test.c @ 1790:42745af83b7d

Introduce extra delay before closing unauthenticated sessions To make it harder for attackers, introduce a delay to keep an unauthenticated session open a bit longer, thus blocking a connection slot until after the delay. Without this, while there is a limit on the amount of attempts an attacker can make at the same time (MAX_UNAUTH_PER_IP), the time taken by dropbear to handle one attempt is still short and thus for each of the allowed parallel attempts many attempts can be chained one after the other. The attempt rate is then: "MAX_UNAUTH_PER_IP / <process time of one attempt>". With the delay, this rate becomes: "MAX_UNAUTH_PER_IP / UNAUTH_CLOSE_DELAY".
author Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
date Wed, 15 Feb 2017 13:53:04 +0100
parents f849a5ca2efc
children
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line source

#include <tomcrypt_test.h>

#ifdef LTC_MDSA

int dsa_test(void)
{
   unsigned char msg[16], out[1024], out2[1024];
   unsigned long x, y;
   int stat1, stat2;
   dsa_key key, key2;

   /* make a random key */
   DO(dsa_make_key(&yarrow_prng, find_prng("yarrow"), 20, 128, &key));

   /* verify it */
   DO(dsa_verify_key(&key, &stat1));
   if (stat1 == 0) { fprintf(stderr, "dsa_verify_key "); return 1; }
   
   /* encrypt a message */
   for (x = 0; x < 16; x++) { msg[x] = x; }
   x = sizeof(out);
   DO(dsa_encrypt_key(msg, 16, out, &x, &yarrow_prng, find_prng("yarrow"), find_hash("sha1"), &key));
   
   /* decrypt */
   y = sizeof(out2);
   DO(dsa_decrypt_key(out, x, out2, &y, &key));
   
   if (y != 16 || memcmp(out2, msg, 16)) {
      fprintf(stderr, "dsa_decrypt failed, y == %lu\n", y);
      return 1;
   }

   /* sign the message */
   x = sizeof(out);
   DO(dsa_sign_hash(msg, sizeof(msg), out, &x, &yarrow_prng, find_prng("yarrow"), &key));

   /* verify it once */
   DO(dsa_verify_hash(out, x, msg, sizeof(msg), &stat1, &key));

   /* Modify and verify again */
   msg[0] ^= 1;
   DO(dsa_verify_hash(out, x, msg, sizeof(msg), &stat2, &key));
   msg[0] ^= 1;
   if (!(stat1 == 1 && stat2 == 0)) { fprintf(stderr, "dsa_verify %d %d", stat1, stat2); return 1; }

   /* test exporting it */
   x = sizeof(out2);
   DO(dsa_export(out2, &x, PK_PRIVATE, &key));
   DO(dsa_import(out2, x, &key2));

   /* verify a signature with it */
   DO(dsa_verify_hash(out, x, msg, sizeof(msg), &stat1, &key2));
   if (stat1 == 0) { fprintf(stderr, "dsa_verify (import private) %d ", stat1); return 1; }
   dsa_free(&key2);

   /* export as public now */
   x = sizeof(out2);
   DO(dsa_export(out2, &x, PK_PUBLIC, &key));

   DO(dsa_import(out2, x, &key2));
   /* verify a signature with it */
   DO(dsa_verify_hash(out, x, msg, sizeof(msg), &stat1, &key2));
   if (stat1 == 0) { fprintf(stderr, "dsa_verify (import public) %d ", stat1); return 1; }
   dsa_free(&key2);
   dsa_free(&key);

   return 0;
}

#else

int dsa_test(void)
{
  fprintf(stderr, "NOP");
  return 0;
}

#endif

/* $Source$ */
/* $Revision$ */
/* $Date$ */