/*

* Poly1305

* (C) 2014 Jack Lloyd

*

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

*/

#ifndef BOTAN_MAC_POLY1305_H_

#define BOTAN_MAC_POLY1305_H_

#include <botan/mac.h>

#include <botan/internal/alignment_buffer.h>

#include <memory>

namespace Botan {

/**

* DJB's Poly1305

* Important note: each key can only be used once

*/

class Poly1305 final : public MessageAuthenticationCode {

   public:

      std::string name() const override { return "Poly1305"; }

      std::unique_ptr<MessageAuthenticationCode> new_object() const override { return std::make_unique<Poly1305>(); }

      void clear() override;

      size_t output_length() const override { return 16; }

      Key_Length_Specification key_spec() const override { return Key_Length_Specification(32); }

      bool fresh_key_required_per_message() const override { return true; }

      bool has_keying_material() const override;

   private:

      void add_data(std::span<const uint8_t>) override;

      void final_result(std::span<uint8_t>) override;

      void key_schedule(std::span<const uint8_t>) override;

      secure_vector<uint64_t> m_poly;

      AlignmentBuffer<uint8_t, 16> m_buffer;

};

}  // namespace Botan

#endif