// Copyright 2022 The BoringSSL Authors

//

// 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

//

//     https://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 OPENSSL_HEADER_CRYPTO_FIPSMODULE_DH_INTERNAL_H

#define OPENSSL_HEADER_CRYPTO_FIPSMODULE_DH_INTERNAL_H

#include <openssl/base.h>

#include "../../internal.h"

#include "../../mem_internal.h"

DECLARE_OPAQUE_STRUCT(dh_st, DHImpl)

BSSL_NAMESPACE_BEGIN

class DHImpl : public dh_st, public RefCounted<DHImpl> {

 public:

  DHImpl() : RefCounted(CheckSubClass()) {}

  UniquePtr<BIGNUM> p;

  UniquePtr<BIGNUM> g;

  UniquePtr<BIGNUM> q;

  UniquePtr<BIGNUM> pub_key;   // g^x mod p

  UniquePtr<BIGNUM> priv_key;  // x

  // priv_length contains the length, in bits, of the private value. If zero,

  // the private value will be the same length as `p`.

  unsigned priv_length = 0;

  mutable Mutex method_mont_p_lock;

  mutable UniquePtr<BN_MONT_CTX> method_mont_p;

 private:

  friend RefCounted;

  ~DHImpl() = default;

};

// dh_check_params_fast checks basic invariants on `dh`'s domain parameters. It

// does not check that `dh` forms a valid group, only that the sizes are within

// DoS bounds.

int dh_check_params_fast(const DH *dh);

// dh_compute_key_padded_no_self_test does the same as `DH_compute_key_padded`,

// but doesn't try to run the self-test first. This is for use in the self tests

// themselves, to prevent an infinite loop.

int dh_compute_key_padded_no_self_test(unsigned char *out,

                                       const BIGNUM *peers_key, DH *dh);

BSSL_NAMESPACE_END

#endif  // OPENSSL_HEADER_CRYPTO_FIPSMODULE_DH_INTERNAL_H