/*

* EMSA1

* (C) 1999-2007 Jack Lloyd

*

* Botan is released under the Simplified BSD License (see license.txt)

*/

#ifndef BOTAN_EMSA1_H_

#define BOTAN_EMSA1_H_

#include <botan/internal/emsa.h>

#include <botan/hash.h>

namespace Botan {

/**

* EMSA1 from IEEE 1363

* Essentially, sign the hash directly

*/

class EMSA1 final : public EMSA

   {

   public:

      /**

      * @param hash the hash function to use

      */

      explicit EMSA1(std::unique_ptr<HashFunction> hash) : m_hash(std::move(hash)) {}

      std::unique_ptr<EMSA> new_object() override;

      std::string name() const override;

      bool requires_message_recovery() const override { return false; }

      AlgorithmIdentifier config_for_x509(const Private_Key& key,

                                          const std::string& cert_hash_name) const override;

   private:

      size_t hash_output_length() const { return m_hash->output_length(); }

      void update(const uint8_t[], size_t) override;

      secure_vector<uint8_t> raw_data() override;

      secure_vector<uint8_t> encoding_of(const secure_vector<uint8_t>& msg,

                                         size_t output_bits,

                                         RandomNumberGenerator& rng) override;

      bool verify(const secure_vector<uint8_t>& coded,

                  const secure_vector<uint8_t>& raw,

                  size_t key_bits) override;

      std::unique_ptr<HashFunction> m_hash;

   };

}

#endif