Renamed class Cipher to GCipher

GCryptLib/src/GCipher.cpp

@@ -0,0 +1,89 @@
+#include <iostream>
+#include <vector>
+#include <stdexcept>
+#include "GCrypt/GCipher.h"
+#include "GCrypt/Util.h"
+#include "GCrypt/InitializationVector.h"
+
+namespace Leonetienne::GCrypt {
+
+  GCipher::GCipher(const Block& key, const DIRECTION direction)
+    :
+    key { key },
+    direction { direction },
+    lastBlock(InitializationVector(key)), // Initialize our lastBlock with some deterministic initial value, based on the key
+    feistel(key) {
+
+    return;
+  }
+
+  GCipher::GCipher(const std::string& password, const DIRECTION direction)
+    :
+    key { PasswordToKey(password) },
+    direction { direction },
+    lastBlock(InitializationVector(key)),  // Initialize our lastBlock with some deterministic initial value, based on the key   feistel(key) {
+    feistel(key) {
+    return;
+  }
+
+  GCipher::~GCipher() {
+    // Clear key memory
+    ZeroKeyMemory();
+
+    return;
+  }
+
+  Block GCipher::Digest(const Block& input) {
+
+    switch (direction) {
+      case DIRECTION::ENCIPHER: {
+        // Rename our input to cleartext
+        const Block& cleartext = input;
+
+        // First, xor our cleartext with the last block, and then encipher it
+        Block ciphertext = feistel.Encipher(cleartext ^ lastBlock);
+
+        // Now set our lastBlock to the ciphertext of this block
+        lastBlock = ciphertext;
+
+        // Now return the ciphertext
+        return ciphertext;
+      }
+
+      case DIRECTION::DECIPHER: {
+        // Rename our input into ciphertext
+        const Block& ciphertext = input;
+
+        // First, decipher our ciphertext, and then xor it with our last block
+        Block cleartext = feistel.Decipher(ciphertext) ^ lastBlock;
+
+        // Now set our lastBLock to the ciphertext of this block
+        lastBlock = ciphertext;
+
+        // Now return the cleartext
+        return cleartext;
+      }
+    }
+
+    throw std::runtime_error("Unreachable branch reached.");
+  }
+
+  // These pragmas only work for MSVC and g++, as far as i know. Beware!!!
+#if defined _WIN32 || defined _WIN64
+#pragma optimize("", off )
+#elif defined __GNUG__
+#pragma GCC push_options
+#pragma GCC optimize ("O0")
+#endif
+  void GCipher::ZeroKeyMemory() {
+    key.reset();
+    return;
+  }
+#if defined _WIN32 || defined _WIN64
+#pragma optimize("", on )
+#elif defined __GNUG__
+#pragma GCC pop_options
+#endif
+
+}
+