/*

* Crystals Dilithium Digital Signature Algorithms

* Based on the public domain reference implementation by the

* designers (https://github.com/pq-crystals/dilithium)

*

* Further changes

* (C) 2021-2023 Jack Lloyd

* (C) 2021-2022 Manuel Glaser - Rohde & Schwarz Cybersecurity

* (C) 2021-2023 Michael Boric, René Meusel - Rohde & Schwarz Cybersecurity

*

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

*/

#ifndef BOTAN_DILITHIUM_COMMON_H_

#define BOTAN_DILITHIUM_COMMON_H_

#include <botan/pk_keys.h>

namespace Botan {

class BOTAN_PUBLIC_API(3,0) DilithiumMode

   {

   public:

      enum Mode

         {

         Dilithium4x4 = 1,

         Dilithium4x4_AES,

         Dilithium6x5,

         Dilithium6x5_AES,

         Dilithium8x7,

         Dilithium8x7_AES

         };

   public:

      DilithiumMode(Mode mode) : m_mode(mode) {}

      explicit DilithiumMode(const OID& oid);

      explicit DilithiumMode(const std::string& str);

      OID get_oid() const;

      std::string to_string() const;

      bool is_aes() const { return m_mode == Dilithium4x4_AES || m_mode == Dilithium6x5_AES || m_mode == Dilithium8x7_AES; }

      bool is_modern() const { return !is_aes(); }

      Mode mode() const { return m_mode; }

   private:

      Mode m_mode;

   };

enum class DilithiumKeyEncoding

   {

   Raw, // as implemented in the reference implementation

   DER  // as described in draft-uni-qsckeys-dilithium/00

        //   Sections 3.3 (private key), 3.6 (public key)

   };

class Dilithium_PublicKeyInternal;

class Dilithium_PrivateKeyInternal;

/**

 * This implementation is based on

 * https://github.com/pq-crystals/dilithium/commit/3e9b9f1412f6c7435dbeb4e10692ea58f181ee51

 *

 * Note that this is _not_ compatible with the round 3 submission of the NIST competition.

 */

class BOTAN_PUBLIC_API(3, 0) Dilithium_PublicKey : public virtual Public_Key

   {

   public:

      Dilithium_PublicKey& operator=(const Dilithium_PublicKey& other) = default;

      virtual ~Dilithium_PublicKey() = default;

      std::string algo_name() const override;

      AlgorithmIdentifier algorithm_identifier() const override;

      OID get_oid() const override;

      size_t key_length() const override;

      size_t estimated_strength() const override;

      std::vector<uint8_t> public_key_bits() const override;

      bool check_key(RandomNumberGenerator&, bool) const override;

      std::unique_ptr<PK_Ops::Verification>

      create_verification_op(const std::string& params,

                             const std::string& provider) const override;

      void set_binary_encoding(DilithiumKeyEncoding encoding)

         {

         m_key_encoding = encoding;

         }

      DilithiumKeyEncoding binary_encoding() const

         {

         return m_key_encoding;

         }

      Dilithium_PublicKey(const AlgorithmIdentifier& alg_id, const std::vector<uint8_t>& pk);

      Dilithium_PublicKey(const std::vector<uint8_t>& pk,

                          DilithiumMode mode, DilithiumKeyEncoding encoding);

   protected:

      Dilithium_PublicKey() : m_key_encoding(DilithiumKeyEncoding::Raw)

         {

         }

      friend class Dilithium_Verification_Operation;

      friend class Dilithium_Signature_Operation;

      std::shared_ptr<Dilithium_PublicKeyInternal> m_public;

      DilithiumKeyEncoding m_key_encoding;

   };

class BOTAN_PUBLIC_API(3, 0) Dilithium_PrivateKey final : public virtual Dilithium_PublicKey,

   public virtual Botan::Private_Key

   {

   public:

      std::unique_ptr<Public_Key> public_key() const override;

      /**

       * Generates a new key pair

       */

      Dilithium_PrivateKey(RandomNumberGenerator& rng, DilithiumMode mode);

      /**

       * Read an encoded private key.

       */

      Dilithium_PrivateKey(const AlgorithmIdentifier& alg_id, const secure_vector<uint8_t>& sk);

      /**

       * Read an encoded private key given the dilithium @p mode and @p encoding.

       */

      Dilithium_PrivateKey(const secure_vector<uint8_t>& sk,

                           DilithiumMode mode, DilithiumKeyEncoding encoding);

      secure_vector<uint8_t> private_key_bits() const override;

      /**

       * Create a signature operation that produces a Dilithium signature either

       * with "Randomized" or "Deterministic" rhoprime. Pass either of those

       * strings as @p params. Default (i.e. empty @p params is "Randomized").

       */

      std::unique_ptr<PK_Ops::Signature> create_signature_op(RandomNumberGenerator&,

            const std::string& params, const std::string& provider) const override;

   private:

      friend class Dilithium_Signature_Operation;

      std::shared_ptr<Dilithium_PrivateKeyInternal> m_private;

   };

} // namespace Botan

#endif