Replicate BattlEye initialization to dump data out of it

be_fn.hpp

#pragma once
#include <stdint.h>
#include <stdio.h>

namespace be
{
	void print_message( const char* msg )
	{
		printf( "[BATTLEYE] %s\n", msg );
	}

	void request_restart( int32_t reason )
	{
		printf( "[BATTLEYE] requested restart with reason 0x%x\n", reason );
	}

	void send_packet( void* packet, int32_t len )
	{
		printf( "[BATTLEYE] called send packet\n" );
	}
}

be_structs.hpp

#pragma once
#include <stdint.h>

namespace be
{
	struct battleye_data_t
	{
		void* pfn_exit;
		void* pfn_run;
		void* pfn_command;
		void* pfn_received_packet;
		void* pfn_on_receive_auth;
		void* pfn_add_peer;
		void* pfn_remove_peer;

		uint8_t* encryption_key;
		int32_t encryption_len;

		void* pfn_encrypt_packet;
		void* pfn_decrypt_packet;
	};

	struct game_data_t
	{
		const char* game_version;
		uint32_t ip_address;
		uint16_t ip_port;

		void ( *pfn_print_msg )( const char* );
		void ( *pfn_request_restart )( int );
		void ( *pfn_send_packet )( void*, int );
		void ( *pfn_disconnect_peer )( void*, int, const char* );
	};
}

main.cpp

#include <windows.h>
#include <iostream>

#include "be_structs.hpp"
#include "be_fn.hpp"

int main( )
{
	const auto lib = LoadLibraryA( "BEClient_x64.dll" );
	const auto init_fn = ( bool( * )( int32_t, be::game_data_t*, be::battleye_data_t* ) )( GetProcAddress( lib, "Init" ) );

	be::battleye_data_t be_data{};
	be::game_data_t game_data{};

	game_data.game_version = "Escape from Tarkov 0.12.6.7865";
	game_data.ip_address = 0;
	game_data.ip_port = 0;

	game_data.pfn_print_msg = &be::print_message;
	game_data.pfn_send_packet = &be::send_packet;
	game_data.pfn_request_restart = &be::request_restart;
	game_data.pfn_disconnect_peer = nullptr;

	uint8_t* encryption_key = ( uint8_t* )( malloc( 256 ) );

	be_data.encryption_key = encryption_key;
	be_data.encryption_len = 256;

	init_fn( 4, &game_data, &be_data );

	printf( "[BATTLEYE] pfnDecryptServerPacket : 0x%p\n", ( char* )( be_data.pfn_decrypt_packet ) - ( char* )( lib ) );

	free( encryption_key );

	std::cin.ignore( );
}