/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * 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.
 */

#pragma once

#include <glog/logging.h>

#include <folly/Memory.h>
#include <folly/portability/OpenSSL.h>

namespace folly {
namespace ssl {

//  helper which translates:
//    FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(Foo, FOO, FOO_free);
//  into
//    using FooDeleter = folly::static_function_deleter<FOO, &FOO_free>;
//    using FooUniquePtr = std::unique_ptr<FOO, FooDeleter>;
#define FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(alias, object, deleter)           \
  using alias##Deleter = folly::static_function_deleter<object, &deleter>; \
  using alias##UniquePtr = std::unique_ptr<object, alias##Deleter>

// ASN1
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(ASN1Time, ASN1_TIME, ASN1_TIME_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    ASN1Ia5Str, ASN1_IA5STRING, ASN1_IA5STRING_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(ASN1Int, ASN1_INTEGER, ASN1_INTEGER_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(ASN1Obj, ASN1_OBJECT, ASN1_OBJECT_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(ASN1Str, ASN1_STRING, ASN1_STRING_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(ASN1Type, ASN1_TYPE, ASN1_TYPE_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    ASN1UTF8Str, ASN1_UTF8STRING, ASN1_UTF8STRING_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    ASN1BitStr, ASN1_BIT_STRING, ASN1_BIT_STRING_free);

// X509
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509, X509, X509_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    X509Extension, X509_EXTENSION, X509_EXTENSION_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Store, X509_STORE, X509_STORE_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    X509StoreCtx, X509_STORE_CTX, X509_STORE_CTX_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Sig, X509_SIG, X509_SIG_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Algor, X509_ALGOR, X509_ALGOR_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Pubkey, X509_PUBKEY, X509_PUBKEY_free);
using X509VerifyParamDeleter =
    folly::static_function_deleter<X509_VERIFY_PARAM, &X509_VERIFY_PARAM_free>;
using X509VerifyParam =
    std::unique_ptr<X509_VERIFY_PARAM, X509VerifyParamDeleter>;

FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(GeneralName, GENERAL_NAME, GENERAL_NAME_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    GeneralNames, GENERAL_NAMES, GENERAL_NAMES_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    AccessDescription, ACCESS_DESCRIPTION, ACCESS_DESCRIPTION_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    AuthorityInfoAccess, AUTHORITY_INFO_ACCESS, AUTHORITY_INFO_ACCESS_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    DistPointName, DIST_POINT_NAME, DIST_POINT_NAME_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(DistPoint, DIST_POINT, DIST_POINT_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    CrlDistPoints, CRL_DIST_POINTS, CRL_DIST_POINTS_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Crl, X509_CRL, X509_CRL_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Name, X509_NAME, X509_NAME_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Req, X509_REQ, X509_REQ_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(X509Revoked, X509_REVOKED, X509_REVOKED_free);

// EVP
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(EvpPkey, EVP_PKEY, EVP_PKEY_free);
using EvpPkeySharedPtr = std::shared_ptr<EVP_PKEY>;

FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    EvpEncodeCtx, EVP_ENCODE_CTX, EVP_ENCODE_CTX_free);

FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(EvpPkeyCtx, EVP_PKEY_CTX, EVP_PKEY_CTX_free);

FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(EvpMdCtx, EVP_MD_CTX, EVP_MD_CTX_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    EvpCipherCtx, EVP_CIPHER_CTX, EVP_CIPHER_CTX_free);

// HMAC
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(HmacCtx, HMAC_CTX, HMAC_CTX_free);

// BIO
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(BioMethod, BIO_METHOD, BIO_meth_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(Bio, BIO, BIO_vfree);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(BioChain, BIO, BIO_free_all);
inline void BIO_free_fb(BIO* bio) {
  CHECK_EQ(1, BIO_free(bio));
}
using BioDeleterFb = folly::static_function_deleter<BIO, &BIO_free_fb>;
using BioUniquePtrFb = std::unique_ptr<BIO, BioDeleterFb>;

// RSA and EC
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(Rsa, RSA, RSA_free);
#ifndef OPENSSL_NO_EC
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(EcKey, EC_KEY, EC_KEY_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(EcGroup, EC_GROUP, EC_GROUP_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(EcPoint, EC_POINT, EC_POINT_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(EcdsaSig, ECDSA_SIG, ECDSA_SIG_free);
#endif

// DSA
#ifndef OPENSSL_NO_DSA
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(Dsa, DSA, DSA_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(DsaSig, DSA_SIG, DSA_SIG_free);
#endif

// BIGNUMs
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(BIGNUM, BIGNUM, BN_clear_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(BNCtx, BN_CTX, BN_CTX_free);

// SSL and SSL_CTX
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(SSL, SSL, SSL_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(SSLSession, SSL_SESSION, SSL_SESSION_free);

// OCSP
#ifndef OPENSSL_NO_OCSP
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(OcspRequest, OCSP_REQUEST, OCSP_REQUEST_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    OcspResponse, OCSP_RESPONSE, OCSP_RESPONSE_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(
    OcspBasicResponse, OCSP_BASICRESP, OCSP_BASICRESP_free);
FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE(OcspCertId, OCSP_CERTID, OCSP_CERTID_free);
#endif

// OpenSSL STACK_OF(T) can both represent owned or borrowed values.
//
// This isn't represented in the OpenSSL "safestack" type (e.g. STACK_OF(Foo)).
// Whether or not a STACK is owning or borrowing is determined purely based on
// which destructor is called.
// * sk_T_free     - This only deallocates the STACK, but does not free the
//                   contained items within. This is the "borrowing" version.
// * sk_T_pop_free - This deallocates both the STACK and it invokes a free
//                   function for each element. This is the "owning" version.
//
// The below macro,
//    FOLLY_SSL_DETAIL_DEFINE_STACK_PTR_TYPE(Alias, Element)
//
// can be used to define two unique_ptr types that correspond to the "owned"
// or "borrowing" version of each.
//
// For example,
//    FOLLY_SSL_DETAIL_DEFINE_STACK_PTR_TYPE(X509Name, X509_NAME)
// creates two unique ptr type aliases
//    * OwningStackOfX509NameUniquePtr
//    * BorrowingStackOfX509NameUniquePtr
// which corresponds to a unique_ptr of `STACK_OF(X509_NAME)` that will invoke
// the appropriate destructor:
//    * OwningStackOf* -> Invokes sk_T_pop_free
//    * BorrowingStackOf* -> Invokes sk_T_free
namespace detail {
template <
    class StackType,
    class ElementType,
    void (*ElementDestructor)(ElementType*)>
struct OpenSSLOwnedStackDeleter {
  void operator()(StackType* stack) const {
    OPENSSL_sk_pop_free(
        reinterpret_cast<OPENSSL_STACK*>(stack),
        reinterpret_cast<OPENSSL_sk_freefunc>(ElementDestructor));
  }
};

template <class StackType>
struct OpenSSLBorrowedStackDestructor {
  void operator()(StackType* stack) {
    OPENSSL_sk_free(reinterpret_cast<OPENSSL_STACK*>(stack));
  }
};

} // namespace detail

#define FOLLY_SSL_DETAIL_OWNING_STACK_DESTRUCTOR(T) \
  ::folly::ssl::detail::OpenSSLOwnedStackDeleter<STACK_OF(T), T, T##_free>

#define FOLLY_SSL_DETAIL_BORROWING_STACK_DESTRUCTOR(T) \
  ::folly::ssl::detail::OpenSSLBorrowedStackDestructor<STACK_OF(T)>

#define FOLLY_SSL_DETAIL_DEFINE_OWNING_STACK_PTR_TYPE(             \
    element_alias, element_type)                                   \
  using OwningStackOf##element_alias##UniquePtr = std::unique_ptr< \
      STACK_OF(element_type),                                      \
      FOLLY_SSL_DETAIL_OWNING_STACK_DESTRUCTOR(element_type)>

#define FOLLY_SSL_DETAIL_DEFINE_BORROWING_STACK_PTR_TYPE(             \
    element_alias, element_type)                                      \
  using BorrowingStackOf##element_alias##UniquePtr = std::unique_ptr< \
      STACK_OF(element_type),                                         \
      FOLLY_SSL_DETAIL_BORROWING_STACK_DESTRUCTOR(element_type)>

#define FOLLY_SSL_DETAIL_DEFINE_STACK_PTR_TYPE(element_alias, element_type) \
  FOLLY_SSL_DETAIL_DEFINE_BORROWING_STACK_PTR_TYPE(                         \
      element_alias, element_type);                                         \
  FOLLY_SSL_DETAIL_DEFINE_OWNING_STACK_PTR_TYPE(element_alias, element_type)

FOLLY_SSL_DETAIL_DEFINE_STACK_PTR_TYPE(X509Name, X509_NAME);
FOLLY_SSL_DETAIL_DEFINE_STACK_PTR_TYPE(X509, X509);

#undef FOLLY_SSL_DETAIL_BORROWING_STACK_DESTRUCTOR
#undef FOLLY_SSL_DETAIL_OWNING_STACK_DESTRUCTOR
#undef FOLLY_SSL_DETAIL_DEFINE_OWNING_STACK_PTR_TYPE
#undef FOLLY_SSL_DETAIL_DEFINE_BORROWING_STACK_PTR_TYPE
#undef FOLLY_SSL_DETAIL_DEFINE_STACK_PTR_TYPE
#undef FOLLY_SSL_DETAIL_DEFINE_PTR_TYPE

} // namespace ssl
} // namespace folly
