Replaced random oracle instantiation to fixed-key HMAC in BIP derivat…

…ion. Static method random_oracle_hash was added.
eckelj · Apr 11, 2019 · f8b6192 · f8b6192
1 parent 358de5f
commit f8b6192
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Showing 3 changed files with 14 additions and 14 deletions.
diff --git a/src/crypto_utils/crypto_hash.h b/src/crypto_utils/crypto_hash.h
@@ -376,4 +376,10 @@ class hmac_sha256_t : public hmac_template_t<hash_e::sha256>
 
 };
 
+inline buf256_t random_oracle_hash(mem_t input)
+{
+  static const byte_t random_oracle_key[16] = {0xf4, 0x91, 0xf2, 0x73, 0x2b, 0x8d, 0x40, 0xe7, 0x81, 0x2b, 0x53, 0x5c, 0x6e, 0xa5, 0xbb, 0xc4};
+  return hmac_sha256_t(mem_t(random_oracle_key, 16)).calculate(input);
+}
+
 } //namespace crypto
diff --git a/src/mpc_crypto_test.cpp b/src/mpc_crypto_test.cpp
@@ -559,14 +559,13 @@ static int test_bip()
   return rv;
 }
 
-namespace mpc {
-extern int zk_paillier_range_time;
-}
 
 MPCCRYPTO_API int MPCCrypto_test()
 {
   int rv = 0;
-  /*
+
+  if (rv = test_bip()) return rv;
+
   test_key_t eddsa_key;
   if (rv = test_eddsa_gen(eddsa_key)) return rv;
   if (rv = test_eddsa_backup(eddsa_key)) return rv;
@@ -576,36 +575,30 @@ MPCCRYPTO_API int MPCCrypto_test()
     if (rv = test_refresh(eddsa_key)) return rv;
   }
 
-  */
+
   test_key_t ecdsa_key;
   if (rv = test_ecdsa_gen(ecdsa_key)) return rv;
 
-  uint64_t t = ub::read_timer_ms();
   for (int i=0; i<10; i++)
   {
     if (rv = test_ecdsa_sign(ecdsa_key)) return rv;
   }
-  t = ub::read_timer_ms() - t;
 
-  /*
+
   if (rv = test_ecdsa_backup(ecdsa_key)) return rv;
   for (int i=0; i<3; i++)
   {
     if (rv = test_ecdsa_sign(ecdsa_key)) return rv;
     if (rv = test_refresh(ecdsa_key)) return rv;
   }
 
-
-  if (rv = test_bip()) return rv;
-
   test_key_t secret_key1; if (rv = test_generic_secret_import(secret_key1)) return rv;
   test_key_t secret_key2; if (rv = test_generic_secret_gen(secret_key2)) return rv;
   for (int i = 0; i<3; i++)
   {
     if (rv = test_refresh(secret_key2)) return rv;
   }
-  */
-  printf("\nAll tests successfully finished. 10 Signatures took %d ms\n", int(t));
+
   return rv;
 }
 
diff --git a/src/mpc_protocols/mpc_eddsa.cpp b/src/mpc_protocols/mpc_eddsa.cpp
@@ -263,7 +263,8 @@ ecc_point_t tweak_to_point(mem_t tweak) // static
   bn_t p, a, b;
   crypto::curve_p256.get_params(p, a, b);
 
-  buf256_t h = sha256_t::hash(tweak);
+  buf256_t h = crypto::random_oracle_hash(tweak);
+
   bn_t x = bn_t(h) % p;
 
   ecc_point_t point(crypto::curve_p256);