view libtomcrypt/testprof/pkcs_1_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
line wrap: on
line source

#include <tomcrypt_test.h>

#ifdef LTC_PKCS_1

int pkcs_1_test(void)
{
   unsigned char buf[3][128];
   int res1, res2, res3, prng_idx, hash_idx, err;
   unsigned long x, y, l1, l2, l3, i1, i2, lparamlen, saltlen, modlen;
   static const unsigned char lparam[] = { 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16 };

   /* get hash/prng  */
   hash_idx = find_hash("sha1");
   prng_idx = find_prng("yarrow");
   
   if (hash_idx == -1 || prng_idx == -1) {
      fprintf(stderr, "pkcs_1 tests require sha1/yarrow");
      return 1;
   }   

   srand(time(NULL));
   /* do many tests */
   for (x = 0; x < 100; x++) {
      zeromem(buf, sizeof(buf));

      /* make a dummy message (of random length) */
      l3 = (rand() & 31) + 8;
      for (y = 0; y < l3; y++) buf[0][y] = rand() & 255;

      /* pick a random lparam len [0..16] */
      lparamlen = abs(rand()) % 17;

      /* pick a random saltlen 0..16 */
      saltlen   = abs(rand()) % 17;

      /* LTC_PKCS #1 v2.0 supports modlens not multiple of 8 */
      modlen = 800 + (abs(rand()) % 224);

      /* encode it */
      l1 = sizeof(buf[1]);
      DO(pkcs_1_oaep_encode(buf[0], l3, lparam, lparamlen, modlen, &yarrow_prng, prng_idx, hash_idx, buf[1], &l1));

      /* decode it */
      l2 = sizeof(buf[2]);
      DO(pkcs_1_oaep_decode(buf[1], l1, lparam, lparamlen, modlen, hash_idx, buf[2], &l2, &res1));

      if (res1 != 1 || l2 != l3 || memcmp(buf[2], buf[0], l3) != 0) {
         fprintf(stderr, "Outsize == %lu, should have been %lu, res1 = %d, lparamlen = %lu, msg contents follow.\n", l2, l3, res1, lparamlen);
         fprintf(stderr, "ORIGINAL:\n");
         for (x = 0; x < l3; x++) {
             fprintf(stderr, "%02x ", buf[0][x]);
         }
         fprintf(stderr, "\nRESULT:\n");
         for (x = 0; x < l2; x++) {
             fprintf(stderr, "%02x ", buf[2][x]);
         }
         fprintf(stderr, "\n\n");
         return 1;
      }

      /* test PSS */
      l1 = sizeof(buf[1]);
      DO(pkcs_1_pss_encode(buf[0], l3, saltlen, &yarrow_prng, prng_idx, hash_idx, modlen, buf[1], &l1));
      DO(pkcs_1_pss_decode(buf[0], l3, buf[1], l1, saltlen, hash_idx, modlen, &res1));
      
      buf[0][i1 = abs(rand()) % l3] ^= 1;
      DO(pkcs_1_pss_decode(buf[0], l3, buf[1], l1, saltlen, hash_idx, modlen, &res2));

      buf[0][i1] ^= 1;
      buf[1][i2 = abs(rand()) % (l1 - 1)] ^= 1;
      pkcs_1_pss_decode(buf[0], l3, buf[1], l1, saltlen, hash_idx, modlen, &res3);
      if (!(res1 == 1 && res2 == 0 && res3 == 0)) {
         fprintf(stderr, "PSS failed: %d, %d, %d, %lu, %lu\n", res1, res2, res3, l3, saltlen);
         return 1;
      }
   }
   return 0;
}

#else

int pkcs_1_test(void)
{
   fprintf(stderr, "NOP");
   return 0;
}

#endif


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