/*
* TLS Cipher Suites
* (C) 2004-2011,2012 Jack Lloyd
*     2016 Matthias Gierlings
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#ifndef BOTAN_TLS_CIPHER_SUITES_H__
#define BOTAN_TLS_CIPHER_SUITES_H__

#include <botan/types.h>
#include <string>
#include <vector>

namespace Botan {

namespace TLS {

/**
* Ciphersuite Information
*/
class BOTAN_DLL Ciphersuite
   {
   public:
      /**
      * Convert an SSL/TLS ciphersuite to algorithm fields
      * @param suite the ciphersuite code number
      * @return ciphersuite object
      */
      static Ciphersuite by_id(u16bit suite);

      static std::vector<u16bit> all_known_ciphersuite_ids();

      /*
      * Returns the compiled in list of cipher suites.
      */
      static const std::vector<Ciphersuite>& all_cipher_suites();

      /**
      * Returns true iff this suite is a known SCSV
      */
      static bool is_scsv(u16bit suite);

      /**
      * Generate a static list of all known ciphersuites and return it.
      *
      * @return list of all known ciphersuites
      */
      static const std::vector<Ciphersuite>& all_known_ciphersuites();

      /**
      * Formats the ciphersuite back to an RFC-style ciphersuite string
      * @return RFC ciphersuite string identifier
      */
      std::string to_string() const { return m_iana_id; }

      /**
      * @return ciphersuite number
      */
      u16bit ciphersuite_code() const { return m_ciphersuite_code; }

      /**
      * @return true if this is a PSK ciphersuite
      */
      bool psk_ciphersuite() const;

      /**
      * @return true if this is an ECC ciphersuite
      */
      bool ecc_ciphersuite() const;

      /**
      * @return key exchange algorithm used by this ciphersuite
      */
      std::string kex_algo() const { return m_kex_algo; }

      /**
      * @return signature algorithm used by this ciphersuite
      */
      std::string sig_algo() const { return m_sig_algo; }

      /**
      * @return symmetric cipher algorithm used by this ciphersuite
      */
      std::string cipher_algo() const { return m_cipher_algo; }

      /**
      * @return message authentication algorithm used by this ciphersuite
      */
      std::string mac_algo() const { return m_mac_algo; }

      std::string prf_algo() const
         {
         if(m_prf_algo && *m_prf_algo)
            return m_prf_algo;
         return m_mac_algo;
         }

      /**
      * @return cipher key length used by this ciphersuite
      */
      size_t cipher_keylen() const { return m_cipher_keylen; }

      size_t nonce_bytes_from_record() const { return m_nonce_bytes_from_record; }

      size_t nonce_bytes_from_handshake() const { return m_nonce_bytes_from_handshake; }

      size_t mac_keylen() const { return m_mac_keylen; }

      /**
      * @return true if this is a valid/known ciphersuite
      */
      bool valid() const;

      Ciphersuite() {}

   private:

       Ciphersuite(u16bit ciphersuite_code,
                   const char* iana_id,
                   const char* sig_algo,
                   const char* kex_algo,
                   const char* cipher_algo,
                   size_t cipher_keylen,
                   size_t nonce_bytes_from_handshake,
                   size_t nonce_bytes_from_record,
                   const char* mac_algo,
                   size_t mac_keylen,
                   const char* prf_algo = "");

      u16bit m_ciphersuite_code = 0;

      /*
      All of these const char* strings are references to compile time
      constants in tls_suite_info.cpp
      */
      const char* m_iana_id;

      const char* m_sig_algo;
      const char* m_kex_algo;
      const char* m_prf_algo;

      const char* m_cipher_algo;
      const char* m_mac_algo;

      size_t m_cipher_keylen = 0;
      size_t m_nonce_bytes_from_handshake = 0;
      size_t m_nonce_bytes_from_record = 0;
      size_t m_mac_keylen = 0;
   };

}

}

#endif