From 4cf79b61adf93ee06ea6c410292f73ebd1e4576f Mon Sep 17 00:00:00 2001
From: hashlag <hashlag@hashlag.net>
Date: Sat, 31 Jan 2026 18:12:43 +0300
Subject: [PATCH] Introduce Block::Encryptor<> CRTP base class.

Inherit DesEncryptor from it.
---
 Chaos/Cipher/Block/Des/DesCrypt.hpp |  4 ++-
 Chaos/Cipher/Block/Encryptor.hpp    | 40 +++++++++++++++++++++++++++
 ChaosTests/Cipher/DesCryptTests.cpp | 43 +++++++++++++++++++++++++++++
 3 files changed, 86 insertions(+), 1 deletion(-)
 create mode 100644 Chaos/Cipher/Block/Encryptor.hpp

diff --git a/Chaos/Cipher/Block/Des/DesCrypt.hpp b/Chaos/Cipher/Block/Des/DesCrypt.hpp
index c2430cf..d4a2c11 100644
--- a/Chaos/Cipher/Block/Des/DesCrypt.hpp
+++ b/Chaos/Cipher/Block/Des/DesCrypt.hpp
@@ -7,6 +7,8 @@
 #include "Service/ChaosException.hpp"
 #include "Service/SeArray.hpp"
 
+#include "Cipher/Block/Encryptor.hpp"
+
 namespace Chaos::Cipher::Block::Des::Inner_
 {
 
@@ -221,7 +223,7 @@ public:
         Inner_::RawKey Key_;
     };
 
-    class DesEncryptor
+    class DesEncryptor : public Encryptor<DesEncryptor>
     {
     public:
         DesEncryptor(const Key & key)
diff --git a/Chaos/Cipher/Block/Encryptor.hpp b/Chaos/Cipher/Block/Encryptor.hpp
new file mode 100644
index 0000000..bf15e5c
--- /dev/null
+++ b/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
diff --git a/ChaosTests/Cipher/DesCryptTests.cpp b/ChaosTests/Cipher/DesCryptTests.cpp
index c10ac14..6b16c80 100644
--- a/ChaosTests/Cipher/DesCryptTests.cpp
+++ b/ChaosTests/Cipher/DesCryptTests.cpp
@@ -1,8 +1,10 @@
 #include <gtest/gtest.h>
 
 #include "Cipher/Block/Des/DesCrypt.hpp"
+#include "Cipher/Block/Encryptor.hpp"
 
 using namespace Chaos::Cipher::Block::Des;
+using namespace Chaos::Cipher::Block;
 
 TEST(DesCryptTests, KeyScheduleTest)
 {
@@ -494,3 +496,44 @@ TEST(DesCryptTests, OutIteratorUsageDecryptTest)
         ASSERT_EQ(8, incrementCalls);
     }
 }
+
+template<typename Impl, typename InputIt>
+static std::array<uint8_t, 8> EncryptThroughBase(Encryptor<Impl> & enc,
+                                                 InputIt begin, InputIt end)
+{
+    std::array<uint8_t, 8> result;
+    enc.EncryptBlock(result.begin(), begin, end);
+    return result;
+}
+
+TEST(DesCryptTests, EncryptThroughBaseTest)
+{
+    std::array<uint8_t, 8> key = { 0x13, 0x34, 0x57, 0x79, 0x9b, 0xbc, 0xdf, 0xf1 };
+
+    std::array<uint8_t, 8> data = { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef };
+    std::array<uint8_t, 8> expected = { 0x85, 0xe8, 0x13, 0x54, 0x0f, 0x0a, 0xb4, 0x05 };
+
+    DesCrypt::Key desKey(key.begin(), key.end());
+    DesCrypt::DesEncryptor enc(desKey);
+
+    ASSERT_EQ(expected, EncryptThroughBase(enc, data.begin(), data.end()));
+}
+
+template<typename Impl>
+static uint64_t EncryptUInt64BlockThroughBase(Encryptor<Impl> & enc, uint64_t block)
+{
+    return enc.EncryptBlock(block);
+}
+
+TEST(DesCryptTests, EncryptUInt64BlockThroughBaseTest)
+{
+    std::array<uint8_t, 8> key = { 0x13, 0x34, 0x57, 0x79, 0x9b, 0xbc, 0xdf, 0xf1 };
+
+    uint64_t data = 0x0123456789abcdef;
+    uint64_t expected = 0x85e813540f0ab405;
+
+    DesCrypt::Key desKey(key.begin(), key.end());
+    DesCrypt::DesEncryptor enc(desKey);
+
+    ASSERT_EQ(expected, EncryptUInt64BlockThroughBase(enc, data));
+}