release/src/router/nettle/testsuite/ecdsa-keygen-test.c

   1 #include "testutils.h"
   2 #include "knuth-lfib.h"
   3
   4 /* Check if y^2 = x^3 - 3x + b */
   5 static int
   6 ecc_valid_p (struct ecc_point *pub)
   7 {
   8   mpz_t t, x, y;
   9   mpz_t lhs, rhs;
  10   int res;
  11   mp_size_t size;
  12
  13   size = pub->ecc->size;
  14
  15   /* First check range */
  16   if (mpn_cmp (pub->p, pub->ecc->p, size) >= 0
  17       || mpn_cmp (pub->p + size, pub->ecc->p, size) >= 0)
  18     return 0;
  19
  20   mpz_init (lhs);
  21   mpz_init (rhs);
  22
  23   mpz_roinit_n (x, pub->p, size);
  24   mpz_roinit_n (y, pub->p + size, size);
  25
  26   mpz_mul (lhs, y, y);
  27   mpz_mul (rhs, x, x);
  28   mpz_sub_ui (rhs, rhs, 3);
  29   mpz_mul (rhs, rhs, x);
  30   mpz_add (rhs, rhs, mpz_roinit_n (t, pub->ecc->b, size));
  31
  32   res = mpz_congruent_p (lhs, rhs, mpz_roinit_n (t, pub->ecc->p, size));
  33
  34   mpz_clear (lhs);
  35   mpz_clear (rhs);
  36
  37   return res;
  38 }
  39
  40 void
  41 test_main (void)
  42 {
  43   unsigned i;
  44   struct knuth_lfib_ctx rctx;
  45   struct dsa_signature signature;
  46
  47   struct tstring *digest;
  48
  49   knuth_lfib_init (&rctx, 4711);
  50   dsa_signature_init (&signature);
  51
  52   digest = SHEX (/* sha256("abc") */
  53                  "BA7816BF 8F01CFEA 414140DE 5DAE2223"
  54                  "B00361A3 96177A9C B410FF61 F20015AD");
  55
  56   for (i = 0; ecc_curves[i]; i++)
  57     {
  58       const struct ecc_curve *ecc = ecc_curves[i];
  59       struct ecc_point pub;
  60       struct ecc_scalar key;
  61
  62       if (verbose)
  63         fprintf (stderr, "Curve %d\n", ecc->bit_size);
  64
  65       ecc_point_init (&pub, ecc);
  66       ecc_scalar_init (&key, ecc);
  67
  68       ecdsa_generate_keypair (&pub, &key,
  69                               &rctx,
  70                               (nettle_random_func *) knuth_lfib_random);
  71
  72       if (verbose)
  73         {
  74           gmp_fprintf (stderr,
  75                        "Public key:\nx = %Nx\ny = %Nx\n",
  76                        pub.p, ecc->size, pub.p + ecc->size, ecc->size);
  77           gmp_fprintf (stderr,
  78                        "Private key: %Nx\n", key.p, ecc->size);
  79         }
  80       if (!ecc_valid_p (&pub))
  81         die ("ecdsa_generate_keypair produced an invalid point.\n");
  82
  83       ecdsa_sign (&key,
  84                   &rctx, (nettle_random_func *) knuth_lfib_random,
  85                   digest->length, digest->data,
  86                   &signature);
  87
  88       if (!ecdsa_verify (&pub, digest->length, digest->data,
  89                           &signature))
  90         die ("ecdsa_verify failed.\n");
  91
  92       digest->data[3] ^= 17;
  93       if (ecdsa_verify (&pub, digest->length, digest->data,
  94                          &signature))
  95         die ("ecdsa_verify  returned success with invalid digest.\n");
  96       digest->data[3] ^= 17;
  97
  98       mpz_combit (signature.r, 117);
  99       if (ecdsa_verify (&pub, digest->length, digest->data,
 100                          &signature))
 101         die ("ecdsa_verify  returned success with invalid signature.r.\n");
 102
 103       mpz_combit (signature.r, 117);
 104       mpz_combit (signature.s, 93);
 105       if (ecdsa_verify (&pub, digest->length, digest->data,
 106                          &signature))
 107         die ("ecdsa_verify  returned success with invalid signature.s.\n");
 108
 109       ecc_point_clear (&pub);
 110       ecc_scalar_clear (&key);
 111     }
 112   dsa_signature_clear (&signature);
 113 }