/*
 *  IXSocketOpenSSL.h
 *  Author: Benjamin Sergeant, Matt DeBoer
 *  Copyright (c) 2017-2020 Machine Zone, Inc. All rights reserved.
 */
#ifdef IXWEBSOCKET_USE_OPEN_SSL

#pragma once

#include "IXCancellationRequest.h"
#include "IXSocket.h"
#include "IXSocketTLSOptions.h"
#include <mutex>
#include <openssl/bio.h>
#include <openssl/conf.h>
#include <openssl/err.h>
#include <openssl/hmac.h>
#include <openssl/ssl.h>

namespace ix
{
class SocketOpenSSL final : public Socket
{
public:
    SocketOpenSSL(const SocketTLSOptions &tlsOptions, int fd = -1);
    ~SocketOpenSSL();

    virtual bool accept(std::string &errMsg) final;

    virtual bool
        connect(const std::string &host,
                int port,
                std::string &errMsg,
                const CancellationRequest &isCancellationRequested) final;
    virtual void close() final;

    virtual ssize_t send(char *buffer, size_t length) final;
    virtual ssize_t recv(void *buffer, size_t length) final;

private:
    void openSSLInitialize();
    std::string getSSLError(int ret);
    SSL_CTX *openSSLCreateContext(std::string &errMsg);
    bool openSSLAddCARootsFromString(const std::string roots);
    bool openSSLClientHandshake(
        const std::string &hostname,
        std::string &errMsg,
        const CancellationRequest &isCancellationRequested);
    bool openSSLCheckServerCert(SSL *ssl,
                                const std::string &hostname,
                                std::string &errMsg);
    bool checkHost(const std::string &host, const char *pattern);
    bool handleTLSOptions(std::string &errMsg);
    bool openSSLServerHandshake(std::string &errMsg);

    // Required for OpenSSL < 1.1
    static void openSSLLockingCallback(int mode,
                                       int type,
                                       const char * /*file*/,
                                       int /*line*/);

    SSL *_ssl_connection;
    SSL_CTX *_ssl_context;
    const SSL_METHOD *_ssl_method;
    SocketTLSOptions _tlsOptions;

    mutable std::mutex _mutex; // OpenSSL routines are not thread-safe

    static std::once_flag _openSSLInitFlag;
    static std::atomic<bool> _openSSLInitializationSuccessful;
};

} // namespace ix

#endif // IXWEBSOCKET_USE_OPEN_SSL