/** * Stream Cipher * (C) 1999-2007 Jack Lloyd * * Distributed under the terms of the Botan license */ #ifndef BOTAN_STREAM_CIPHER_H__ #define BOTAN_STREAM_CIPHER_H__ #include namespace Botan { /* * Stream Cipher */ class BOTAN_DLL StreamCipher : public SymmetricAlgorithm { public: /** * Encrypt or decrypt a message * @param in the plaintext * @param out the byte array to hold the output, i.e. the ciphertext * @param len the length of both in and out in bytes */ virtual void cipher(const byte in[], byte out[], u32bit len) = 0; /** * Encrypt or decrypt a message * @param buf the plaintext / ciphertext * @param len the length of buf in bytes */ void cipher1(byte buf[], u32bit len) { cipher(buf, buf, len); } /** * Resync the cipher using the IV * @param iv the initialization vector * @param iv_len the length of the IV in bytes */ virtual void set_iv(const byte[], u32bit iv_len) { if(iv_len) throw Invalid_Argument("The stream cipher " + name() + " does not support resyncronization"); } /** * @param iv_len the length of the IV in bytes * @return if the length is valid for this algorithm */ virtual bool valid_iv_length(u32bit iv_len) const { return (iv_len == 0); } /** * Get a new object representing the same algorithm as *this */ virtual StreamCipher* clone() const = 0; /** * Zeroize internal state */ virtual void clear() = 0; /** * StreamCipher constructor */ StreamCipher(u32bit key_min, u32bit key_max = 0, u32bit key_mod = 1) : SymmetricAlgorithm(key_min, key_max, key_mod) {} virtual ~StreamCipher() {} }; } #endif