/*

* (C) 2018,2019 Jack Lloyd

*

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

*/

#ifndef BOTAN_PBKDF_BCRYPT_H_

#define BOTAN_PBKDF_BCRYPT_H_

#include <botan/pwdhash.h>

//BOTAN_FUTURE_INTERNAL_HEADER(bcrypt_pbkdf.h)

namespace Botan {

/**

* Bcrypt-PBKDF key derivation function

*/

class BOTAN_PUBLIC_API(2,11) Bcrypt_PBKDF final : public PasswordHash

   {

   public:

      Bcrypt_PBKDF(size_t iterations) : m_iterations(iterations) {}

      Bcrypt_PBKDF(const Bcrypt_PBKDF& other) = default;

      Bcrypt_PBKDF& operator=(const Bcrypt_PBKDF&) = default;

      /**

      * Derive a new key under the current Bcrypt-PBKDF parameter set

      */

      void derive_key(uint8_t out[], size_t out_len,

                      const char* password, size_t password_len,

                      const uint8_t salt[], size_t salt_len) const override;

      std::string to_string() const override;

      size_t iterations() const override { return m_iterations; }

      size_t parallelism() const override { return 0; }

      size_t memory_param() const override { return 0; }

      size_t total_memory_usage() const override { return 4096; }

   private:

      size_t m_iterations;

   };

class BOTAN_PUBLIC_API(2,11) Bcrypt_PBKDF_Family final : public PasswordHashFamily

   {

   public:

      Bcrypt_PBKDF_Family() {}

      std::string name() const override;

      std::unique_ptr<PasswordHash> tune(size_t output_length,

                                         std::chrono::milliseconds msec,

                                         size_t max_memory) const override;

      std::unique_ptr<PasswordHash> default_params() const override;

      std::unique_ptr<PasswordHash> from_iterations(size_t iter) const override;

      std::unique_ptr<PasswordHash> from_params(

         size_t i, size_t, size_t) const override;

   };

/**

* Bcrypt PBKDF compatible with OpenBSD bcrypt_pbkdf

*/

void BOTAN_UNSTABLE_API bcrypt_pbkdf(uint8_t output[], size_t output_len,

                                     const char* pass, size_t pass_len,

                                     const uint8_t salt[], size_t salt_len,

                                     size_t rounds);

}

#endif