Introduce Block::Encryptor<> CRTP base class.

Inherit DesEncryptor from it.

Chaos/Cipher/Block/Encryptor.hpp

@@ -0,0 +1,40 @@
+#ifndef CHAOS_CIPHER_BLOCK_ENCRYPTOR_HPP
+#define CHAOS_CIPHER_BLOCK_ENCRYPTOR_HPP
+
+namespace Chaos::Cipher::Block
+{
+
+template<typename T>
+class Encryptor
+{
+public:
+    template<typename OutputIt, typename InputIt>
+    void EncryptBlock(OutputIt out, InputIt inBegin, InputIt inEnd)
+    {
+        Impl().EncryptBlock(out, inBegin, inEnd);
+    }
+
+    template<typename Block>
+    auto EncryptBlock(Block block)
+    {
+        return Impl().EncryptBlock(block);
+    }
+
+protected:
+    Encryptor() = default;
+
+private:
+    const T & Impl() const
+    {
+        return static_cast<const T &>(*this);
+    }
+
+    T & Impl()
+    {
+        return static_cast<T &>(*this);
+    }
+};
+
+} // namespace Chaos::Cipher::Block
+
+#endif // CHAOS_CIPHER_BLOCK_ENCRYPTOR_HPP