include/fc/container/zeroed_array.hpp

@@ -0,0 +1,72 @@
+#pragma once
+/*
+ * Copyright (c) 2019 BitShares Blockchain Foundation, and contributors
+ *
+ * The MIT License
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include <fc/io/raw_fwd.hpp>
+
+namespace fc {
+
+   template< typename T, size_t N >
+   class zero_initialized_array;
+
+   template< size_t N >
+   class zero_initialized_array< unsigned char, N > : public std::array< unsigned char, N > {
+      public:
+         zero_initialized_array() : std::array< unsigned char, N >() { }
+   };
+
+   template<typename T,size_t N>
+   struct get_typename< zero_initialized_array<T,N> >
+   {
+      static const char* name()
+      {
+         static std::string _name = std::string("zero_initialized_array<")
+                                    + std::string(fc::get_typename<T>::name())
+                                    + "," + fc::to_string(N) + ">";
+         return _name.c_str();
+      }
+   };
+
+   class variant;
+   template<size_t N>
+   void to_variant( const zero_initialized_array<unsigned char,N>& bi, variant& v, uint32_t max_depth = 1 )
+   {
+      to_variant( static_cast<const std::array<unsigned char,N>&>( bi ), v, max_depth );
+   }
+   template<size_t N>
+   void from_variant( const variant& v, zero_initialized_array<unsigned char,N>& bi, uint32_t max_depth = 1 )
+   {
+      from_variant( v, static_cast<std::array<unsigned char,N>&>( bi ), max_depth );
+   }
+
+   namespace raw {
+      template<typename Stream, size_t N>
+      inline void pack( Stream& s, const zero_initialized_array<unsigned char,N>& v, uint32_t _max_depth ) {
+         pack( s, static_cast<const std::array<unsigned char,N>&>( v ), _max_depth );
+      }
+      template<typename Stream, size_t N>
+      inline void unpack( Stream& s, zero_initialized_array<unsigned char,N>& v, uint32_t _max_depth ) { try {
+         unpack( s, static_cast<std::array<unsigned char,N>&>( v ), _max_depth );
+      } FC_RETHROW_EXCEPTIONS( warn, "zero_initialized_array<unsigned char,${length}>", ("length",N) ) }
+   }
+}

include/fc/crypto/elliptic.hpp

@@ -1,4 +1,5 @@
 #pragma once
+#include <fc/container/zeroed_array.hpp>
 #include <fc/crypto/bigint.hpp>
 #include <fc/crypto/openssl.hpp>
 #include <fc/crypto/sha256.hpp>
@@ -17,15 +18,15 @@ namespace fc {
       class private_key_impl;
     }
 
-    typedef fc::sha256                   blind_factor_type;
-    typedef std::array<unsigned char,33> commitment_type;
-    typedef std::array<unsigned char,33> public_key_data;
-    typedef fc::sha256                   private_key_secret;
-    typedef std::array<unsigned char,65> public_key_point_data; ///< the full non-compressed version of the ECC point
-    typedef std::array<unsigned char,72> signature;
-    typedef std::array<unsigned char,65> compact_signature;
-    typedef std::vector<char>            range_proof_type;
-    typedef std::array<unsigned char,78> extended_key_data;
+    typedef fc::sha256                               blind_factor_type;
+    typedef zero_initialized_array<unsigned char,33> commitment_type;
+    typedef zero_initialized_array<unsigned char,33> public_key_data;
+    typedef fc::sha256                               private_key_secret;
+    typedef zero_initialized_array<unsigned char,65> public_key_point_data; ///< the full non-compressed version of the ECC point
+    typedef zero_initialized_array<unsigned char,72> signature;
+    typedef zero_initialized_array<unsigned char,65> compact_signature;
+    typedef std::vector<char>                        range_proof_type;
+    typedef zero_initialized_array<unsigned char,78> extended_key_data;
 
     /**
      *  @class public_key

src/crypto/elliptic_common.cpp

@@ -19,7 +19,7 @@
 namespace fc { namespace ecc {
 
     namespace detail {
-        typedef std::array<unsigned char,37> chr37;
+        typedef zero_initialized_array<unsigned char,37> chr37;
 
         fc::sha256 _left( const fc::sha512& v )
         {

src/crypto/elliptic_secp256k1.cpp

@@ -53,7 +53,7 @@ namespace fc { namespace ecc {
                 public_key_data _key;
         };
 
-        typedef std::array<unsigned char,37> chr37;
+        typedef zero_initialized_array<unsigned char,37> chr37;
         chr37 _derive_message( const public_key_data& key, int i );
         fc::sha256 _left( const fc::sha512& v );
         fc::sha256 _right( const fc::sha512& v );