text: // Copyright 2021 Google LLC
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //     http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  //
  ///////////////////////////////////////////////////////////////////////////////
  
  #ifndef THIRD_PARTY_TINK_EXPERIMENTAL_PQCRYPTO_CC_HYBRID_INTERNAL_CECPQ2_AEAD_HKDF_HYBRID_DECRYPT_H_
  #define THIRD_PARTY_TINK_EXPERIMENTAL_PQCRYPTO_CC_HYBRID_INTERNAL_CECPQ2_AEAD_HKDF_HYBRID_DECRYPT_H_
  
  #include <memory>
  #include <utility>
  
  #include "tink/hybrid_decrypt.h"
  #include "tink/util/statusor.h"
  #include "pqcrypto/cc/hybrid/cecpq2_aead_hkdf_dem_helper.h"
  #include "pqcrypto/cc/subtle/cecpq2_hkdf_recipient_kem_boringssl.h"
  #include "pqcrypto/cc/subtle/cecpq2_subtle_boringssl_util.h"
  #include "pqcrypto/proto/cecpq2_aead_hkdf.pb.h"
  
  namespace crypto {
  namespace tink {
  
  // CECPQ2 decryption with HKDF-KEM (key encapsulation mechanism) and
  // AEAD-DEM (data encapsulation mechanism)
  class Cecpq2AeadHkdfHybridDecrypt : public HybridDecrypt {
   public:
    // Returns an HybridDecrypt-primitive that uses the key material
    // given in 'recipient_key'
    static crypto::tink::util::StatusOr<std::unique_ptr<HybridDecrypt>> New(
        const google::crypto::tink::Cecpq2AeadHkdfPrivateKey& private_key);
  
    crypto::tink::util::StatusOr<std::string> Decrypt(
        absl::string_view ciphertext,
        absl::string_view context_info) const override;
  
   private:
    Cecpq2AeadHkdfHybridDecrypt(
        const google::crypto::tink::Cecpq2AeadHkdfParams& recipient_key_params,
        std::unique_ptr<const subtle::Cecpq2HkdfRecipientKemBoringSsl> kem,
        std::unique_ptr<const Cecpq2AeadHkdfDemHelper> dem_helper)
        : recipient_key_params_(recipient_key_params),
          recipient_kem_(std::move(kem)),
          dem_helper_(std::move(dem_helper)) {}
  
    google::crypto::tink::Cecpq2AeadHkdfParams recipient_key_params_;
    std::unique_ptr<const subtle::Cecpq2HkdfRecipientKemBoringSsl> recipient_kem_;
    std::unique_ptr<const Cecpq2AeadHkdfDemHelper> dem_helper_;
  };
  
  }  // namespace tink
  }  // namespace crypto
  
  #endif  // THIRD_PARTY_TINK_EXPERIMENTAL_PQCRYPTO_CC_HYBRID_INTERNAL_CECPQ2_AEAD_HKDF_HYBRID_DECRYPT_H_
  