message: [RPC] Ensure Tx/Budget input hashes are of the proper length
  Transaction and Budget hashes are always 64 characters in length. Return
  a descriptive error if this is not the case.
diff: @@ -135,13 +135,15 @@ UniValue ValueFromAmount(const CAmount& amount)
  strprintf("%s%d.%08d", sign ? "-" : "", quotient, remainder));
  }
  -uint256 ParseHashV(const UniValue& v, string strName)
  +uint256 ParseHashV(const UniValue& v, std::string strName)
  {
  - string strHex;
  + std::string strHex;
  if (v.isStr())
  strHex = v.get_str();
  if (!IsHex(strHex)) // Note: IsHex("") is false
  throw JSONRPCError(RPC_INVALID_PARAMETER, strName + " must be hexadecimal string (not '" + strHex + "')");
  + if (64 != strHex.length())
  + throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("%s must be of length %d (not %d)", strName, 64, strHex.length()));
  uint256 result;
  result.SetHex(strHex);
  return result;
  