cxx: more algorithm-agnostic API

The code (in the utilities in particular) is a mess though, so a
refactoring's coming up.

1 files changed, 171 insertions, 0 deletions

diff --git a/cxx/include/aesnixx/api.hpp b/cxx/include/aesnixx/api.hpp
new file mode 100644
index 0000000..6995ae2
--- /dev/null
+++ b/cxx/include/aesnixx/api.hpp
@@ -0,0 +1,171 @@
+/**
+ * \file
+ * \author Egor Tensin <Egor.Tensin@gmail.com>
+ * \date 2015
+ * \copyright This file is licensed under the terms of the MIT License.
+ *            See LICENSE.txt for details.
+ */
+
+#pragma once
+
+#include "algorithm.hpp"
+#include "mode.hpp"
+
+#include <cstddef>
+
+#include <string>
+#include <type_traits>
+
+namespace aesni
+{
+    template <Algorithm algorithm>
+    struct Types;
+
+    template <Algorithm algorithm>
+    std::size_t get_number_of_rounds();
+
+    template <Algorithm algorithm>
+    void from_string(
+        typename Types<algorithm>::Block&,
+        const char*);
+
+    template <Algorithm algorithm>
+    inline void from_string(
+        typename Types<algorithm>::Block& dest,
+        const std::string& src)
+    {
+        from_string<algorithm>(dest, src.c_str());
+    }
+
+    template <Algorithm algorithm>
+    std::string to_string(const typename Types<algorithm>::Block&);
+
+    template <Algorithm algorithm>
+    std::string to_matrix_string(const typename Types<algorithm>::Block&);
+
+    template <Algorithm algorithm>
+    void from_string(
+        typename Types<algorithm>::Key&,
+        const char*);
+
+    template <Algorithm algorithm>
+    inline void from_string(
+        typename Types<algorithm>::Key& dest,
+        const std::string& src)
+    {
+        from_string<algorithm>(dest, src.c_str());
+    }
+
+    template <Algorithm algorithm>
+    std::string to_string(const typename Types<algorithm>::Key&);
+
+    template <Algorithm algorithm>
+    inline void expand_key(
+        const typename Types<algorithm>::Key& key,
+        typename Types<algorithm>::RoundKeys& encryption_keys);
+
+    template <Algorithm algorithm>
+    inline void derive_decryption_keys(
+        const typename Types<algorithm>::RoundKeys& encryption_keys,
+        typename Types<algorithm>::RoundKeys& decryption_keys);
+
+    template <Algorithm algorithm, Mode mode, typename std::enable_if<ModeRequiresInitializationVector<mode>::value>::type* = 0>
+    inline void encrypt_block(
+        const typename Types<algorithm>::Block& plaintext,
+        const typename Types<algorithm>::RoundKeys& round_keys,
+        typename Types<algorithm>::Block& iv,
+        typename Types<algorithm>::Block& ciphertext);
+
+    template <Algorithm algorithm, Mode mode, typename std::enable_if<!ModeRequiresInitializationVector<mode>::value>::type* = 0>
+    inline void encrypt_block(
+        const typename Types<algorithm>::Block& plaintext,
+        const typename Types<algorithm>::RoundKeys& round_keys,
+        typename Types<algorithm>::Block& ciphertext);
+
+    template <Algorithm algorithm, Mode mode, typename std::enable_if<!ModeRequiresInitializationVector<mode>::value>::type* = 0>
+    inline void encrypt_block(
+        const typename Types<algorithm>::Block& plaintext,
+        const typename Types<algorithm>::RoundKeys& round_keys,
+        typename Types<algorithm>::Block&,
+        typename Types<algorithm>::Block& ciphertext)
+    {
+        encrypt_block<algorithm, mode>(plaintext, round_keys, ciphertext);
+    }
+
+    template <Algorithm algorithm, Mode mode, typename std::enable_if<ModeRequiresInitializationVector<mode>::value>::type* = 0>
+    inline void decrypt_block(
+        const typename Types<algorithm>::Block& ciphertext,
+        const typename Types<algorithm>::RoundKeys& round_keys,
+        typename Types<algorithm>::Block& iv,
+        typename Types<algorithm>::Block& plaintext);
+
+    template <Algorithm algorithm, Mode mode, typename std::enable_if<!ModeRequiresInitializationVector<mode>::value>::type* = 0>
+    inline void decrypt_block(
+        const typename Types<algorithm>::Block& ciphertext,
+        const typename Types<algorithm>::RoundKeys& round_keys,
+        typename Types<algorithm>::Block& plaintext);
+
+    template <Algorithm algorithm, Mode mode, typename std::enable_if<!ModeRequiresInitializationVector<mode>::value>::type* = 0>
+    inline void decrypt_block(
+        const typename Types<algorithm>::Block& ciphertext,
+        const typename Types<algorithm>::RoundKeys& round_keys,
+        typename Types<algorithm>::Block&,
+        typename Types<algorithm>::Block& plaintext)
+    {
+        decrypt_block<algorithm, mode>(ciphertext, round_keys, plaintext);
+    }
+
+    template <Algorithm algorithm, Mode mode>
+    struct EncryptWrapper
+    {
+        EncryptWrapper(
+            const typename Types<algorithm>::Key& key,
+            const typename Types<algorithm>::Block& iv) : iv(iv)
+        {
+            expand_key<algorithm>(key, encryption_keys);
+        }
+
+        inline void encrypt_block(
+            const typename Types<algorithm>::Block& plaintext,
+            typename Types<algorithm>::Block& ciphertext)
+        {
+            aesni::encrypt_block<algorithm, mode>(
+                plaintext, encryption_keys, iv, ciphertext);
+        }
+
+        typename Types<algorithm>::Block iv;
+        typename Types<algorithm>::RoundKeys encryption_keys;
+    };
+
+    template <Algorithm algorithm, Mode mode>
+    struct DecryptWrapper
+    {
+        DecryptWrapper(
+            const typename Types<algorithm>::Key& key,
+            const typename Types<algorithm>::Block& iv) : iv(iv)
+        {
+            typename Types<algorithm>::RoundKeys encryption_keys;
+            expand_key<algorithm>(key, encryption_keys);
+
+            if (ModeUsesEncryptionKeysOnly<mode>::value)
+            {
+                decryption_keys = encryption_keys;
+            }
+            else
+            {
+                derive_decryption_keys<algorithm>(encryption_keys, decryption_keys);
+            }
+        }
+
+        inline void decrypt_block(
+            const typename Types<algorithm>::Block& ciphertext,
+            typename Types<algorithm>::Block& plaintext)
+        {
+            aesni::decrypt_block<algorithm, mode>(
+                ciphertext, decryption_keys, iv, plaintext);
+        }
+
+        typename Types<algorithm>::Block iv;
+        typename Types<algorithm>::RoundKeys decryption_keys;
+    };
+}