1 files changed, 91 insertions, 0 deletions
diff --git a/lib/modes/cfb/cfb.h b/lib/modes/cfb/cfb.h
new file mode 100644
index 000000000..48be0a2d9
--- /dev/null
+++ b/lib/modes/cfb/cfb.h
@@ -0,0 +1,91 @@
+/*
+* CFB mode
+* (C) 1999-2007,2013 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_MODE_CFB_H__
+#define BOTAN_MODE_CFB_H__
+
+#include <botan/cipher_mode.h>
+#include <botan/block_cipher.h>
+#include <botan/mode_pad.h>
+#include <memory>
+
+namespace Botan {
+
+/**
+* CFB Mode
+*/
+class BOTAN_DLL CFB_Mode : public Cipher_Mode
+   {
+   public:
+      secure_vector<byte> start(const byte nonce[], size_t nonce_len) override;
+
+      std::string name() const override;
+
+      size_t update_granularity() const override;
+
+      size_t minimum_final_size() const override;
+
+      Key_Length_Specification key_spec() const override;
+
+      size_t output_length(size_t input_length) const override;
+
+      size_t default_nonce_length() const override;
+
+      bool valid_nonce_length(size_t n) const override;
+
+      void clear();
+   protected:
+      CFB_Mode(BlockCipher* cipher, size_t feedback_bits);
+
+      const BlockCipher& cipher() const { return *m_cipher; }
+
+      size_t feedback() const { return m_feedback_bytes; }
+
+      secure_vector<byte>& shift_register() { return m_shift_register; }
+
+      secure_vector<byte>& keystream_buf() { return m_keystream_buf; }
+
+   private:
+      void key_schedule(const byte key[], size_t length) override;
+
+      std::unique_ptr<BlockCipher> m_cipher;
+      secure_vector<byte> m_shift_register;
+      secure_vector<byte> m_keystream_buf;
+      size_t m_feedback_bytes;
+   };
+
+/**
+* CFB Encryption
+*/
+class BOTAN_DLL CFB_Encryption : public CFB_Mode
+   {
+   public:
+      CFB_Encryption(BlockCipher* cipher, size_t feedback_bits) :
+         CFB_Mode(cipher, feedback_bits) {}
+
+      void update(secure_vector<byte>& blocks, size_t offset = 0) override;
+
+      void finish(secure_vector<byte>& final_block, size_t offset = 0) override;
+   };
+
+/**
+* CFB Decryption
+*/
+class BOTAN_DLL CFB_Decryption : public CFB_Mode
+   {
+   public:
+      CFB_Decryption(BlockCipher* cipher, size_t feedback_bits) :
+         CFB_Mode(cipher, feedback_bits) {}
+
+      void update(secure_vector<byte>& blocks, size_t offset = 0) override;
+
+      void finish(secure_vector<byte>& final_block, size_t offset = 0) override;
+   };
+
+}
+
+#endif