t8-mod/source/proxy-dll/component/arxan.cpp
2023-11-10 13:52:20 -08:00

512 lines
14 KiB
C++

#include <std_include.hpp>
#include "loader/component_loader.hpp"
#include <utilities/hook.hpp>
#include <utilities/string.hpp>
namespace arxan
{
namespace
{
const std::vector<std::pair<uint8_t*, size_t>>& get_text_sections()
{
static const std::vector<std::pair<uint8_t*, size_t>> text = []
{
std::vector<std::pair<uint8_t*, size_t>> texts{};
const utilities::nt::library game{};
for (const auto& section : game.get_section_headers())
{
if (section->Characteristics & IMAGE_SCN_MEM_EXECUTE)
{
texts.emplace_back(game.get_ptr() + section->VirtualAddress, section->Misc.VirtualSize);
}
}
return texts;
}();
return text;
}
bool is_in_texts(const uint64_t addr)
{
const auto& texts = get_text_sections();
for (const auto& text : texts)
{
const auto start = reinterpret_cast<ULONG_PTR>(text.first);
if (addr >= start && addr <= (start + text.second))
{
return true;
}
}
return false;
}
bool is_in_texts(const void* addr)
{
return is_in_texts(reinterpret_cast<uint64_t>(addr));
}
struct integrity_handler_context
{
uint32_t* computed_checksum;
uint32_t* original_checksum;
};
bool is_on_stack(uint8_t* stack_frame, const void* pointer)
{
const auto stack_value = reinterpret_cast<uint64_t>(stack_frame);
const auto pointer_value = reinterpret_cast<uint64_t>(pointer);
const auto diff = static_cast<int64_t>(stack_value - pointer_value);
return std::abs(diff) < 0x1000;
}
// Pretty trashy, but working, heuristic to search the integrity handler context
bool is_handler_context(uint8_t* stack_frame, const uint32_t computed_checksum, const uint32_t frame_offset)
{
const auto* potential_context = reinterpret_cast<integrity_handler_context*>(stack_frame + frame_offset);
return is_on_stack(stack_frame, potential_context->computed_checksum)
&& *potential_context->computed_checksum == computed_checksum
&& is_in_texts(potential_context->original_checksum);
}
integrity_handler_context* search_handler_context(uint8_t* stack_frame, const uint32_t computed_checksum)
{
for (uint32_t frame_offset = 0; frame_offset < 0x90; frame_offset += 8)
{
if (is_handler_context(stack_frame, computed_checksum, frame_offset))
{
return reinterpret_cast<integrity_handler_context*>(stack_frame + frame_offset);
}
}
return nullptr;
}
uint32_t adjust_integrity_checksum(const uint64_t return_address, uint8_t* stack_frame,
const uint32_t current_checksum)
{
const auto handler_address = reverse_b(return_address - 5);
const auto* context = search_handler_context(stack_frame, current_checksum);
if (!context)
{
MessageBoxA(nullptr, utilities::string::va("No frame offset for: %llX", handler_address), "Error",
MB_ICONERROR);
TerminateProcess(GetCurrentProcess(), 0xBAD);
return current_checksum;
}
const auto correct_checksum = *context->original_checksum;
*context->computed_checksum = correct_checksum;
if (current_checksum != correct_checksum)
{
#ifndef NDEBUG
/*logger::write(logger::LOG_TYPE_DEBUG, "Adjusting checksum (%llX): %X -> %X\n", handler_address,
current_checksum, correct_checksum);*/
#endif
}
return correct_checksum;
}
void patch_intact_basic_block_integrity_check(void* address)
{
const auto game_address = reinterpret_cast<uint64_t>(address);
constexpr auto inst_len = 3;
const auto next_inst_addr = game_address + inst_len;
const auto next_inst = *reinterpret_cast<uint32_t*>(next_inst_addr);
if ((next_inst & 0xFF00FFFF) != 0xFF004583)
{
throw std::runtime_error(utilities::string::va("Unable to patch intact basic block: %llX", game_address));
}
const auto other_frame_offset = static_cast<uint8_t>(next_inst >> 16);
static const auto stub = utilities::hook::assemble([](utilities::hook::assembler& a)
{
a.push(rax);
a.mov(rax, qword_ptr(rsp, 8));
a.sub(rax, 2); // Skip the push we inserted
a.push(rax);
a.pushad64();
a.mov(r8, qword_ptr(rsp, 0x88));
a.mov(rcx, rax);
a.mov(rdx, rbp);
a.call_aligned(adjust_integrity_checksum);
a.mov(qword_ptr(rsp, 0x80), rax);
a.popad64();
a.pop(rax);
a.add(rsp, 8);
a.mov(dword_ptr(rdx, rcx, 4), eax);
a.pop(rax); // return addr
a.xchg(rax, qword_ptr(rsp)); // switch with push
a.add(dword_ptr(rbp, rax), 0xFFFFFFFF);
a.mov(rax, dword_ptr(rdx, rcx, 4)); // restore rax
a.ret();
});
// push other_frame_offset
utilities::hook::set<uint16_t>(game_address, static_cast<uint16_t>(0x6A | (other_frame_offset << 8)));
utilities::hook::call(game_address + 2, stub);
}
void patch_split_basic_block_integrity_check(void* address)
{
const auto game_address = reinterpret_cast<uint64_t>(address);
constexpr auto inst_len = 3;
const auto next_inst_addr = game_address + inst_len;
if (*reinterpret_cast<uint8_t*>(next_inst_addr) != 0xE9)
{
throw std::runtime_error(utilities::string::va("Unable to patch split basic block: %llX", game_address));
}
const auto jump_target = utilities::hook::extract<void*>(reinterpret_cast<void*>(next_inst_addr + 1));
const auto stub = utilities::hook::assemble([jump_target](utilities::hook::assembler& a)
{
a.push(rax);
a.mov(rax, qword_ptr(rsp, 8));
a.push(rax);
a.pushad64();
a.mov(r8, qword_ptr(rsp, 0x88));
a.mov(rcx, rax);
a.mov(rdx, rbp);
a.call_aligned(adjust_integrity_checksum);
a.mov(qword_ptr(rsp, 0x80), rax);
a.popad64();
a.pop(rax);
a.add(rsp, 8);
a.mov(dword_ptr(rdx, rcx, 4), eax);
a.add(rsp, 8);
a.jmp(jump_target);
});
utilities::hook::call(game_address, stub);
}
void search_and_patch_integrity_checks()
{
// There seem to be 1219 results.
// Searching them is quite slow.
// Maybe precomputing that might be better?
const auto intact_results = "89 04 8A 83 45 ? FF"_sig;
const auto split_results = "89 04 8A E9"_sig;
for (auto* i : intact_results)
{
patch_intact_basic_block_integrity_check(i);
}
for (auto* i : split_results)
{
patch_split_basic_block_integrity_check(i);
}
}
void* original_first_tls_callback = nullptr;
void** get_tls_callbacks()
{
const utilities::nt::library game{};
const auto& entry = game.get_optional_header()->DataDirectory[IMAGE_DIRECTORY_ENTRY_TLS];
if (!entry.VirtualAddress || !entry.Size)
{
return nullptr;
}
const auto* tls_dir = reinterpret_cast<IMAGE_TLS_DIRECTORY*>(game.get_ptr() + entry.VirtualAddress);
return reinterpret_cast<void**>(tls_dir->AddressOfCallBacks);
}
void disable_tls_callbacks()
{
auto* tls_callbacks = get_tls_callbacks();
if (tls_callbacks)
{
original_first_tls_callback = *tls_callbacks;
}
utilities::hook::set(tls_callbacks, nullptr);
}
void restore_tls_callbacks()
{
auto* tls_callbacks = get_tls_callbacks();
if (tls_callbacks)
{
utilities::hook::set(tls_callbacks, original_first_tls_callback);
}
}
utilities::hook::detour create_thread_hook;
HANDLE WINAPI create_thread_stub(const LPSECURITY_ATTRIBUTES thread_attributes, const SIZE_T stack_size,
const LPTHREAD_START_ROUTINE start_address, const LPVOID parameter,
const DWORD creation_flags,
const LPDWORD thread_id)
{
if (utilities::nt::library::get_by_address(start_address) == utilities::nt::library{})
{
restore_tls_callbacks();
create_thread_hook.clear();
return CreateThread(thread_attributes, stack_size, start_address, parameter, creation_flags,
thread_id);
}
return create_thread_hook.invoke<HANDLE>(thread_attributes, stack_size, start_address, parameter,
creation_flags, thread_id);
}
utilities::hook::detour get_thread_context_hook;
BOOL WINAPI get_thread_context_stub(const HANDLE thread_handle, const LPCONTEXT context)
{
constexpr auto debug_registers_flag = (CONTEXT_DEBUG_REGISTERS & ~CONTEXT_AMD64);
if (context && (context->ContextFlags & debug_registers_flag))
{
auto* source = _ReturnAddress();
const auto game = utilities::nt::library{};
const auto source_module = utilities::nt::library::get_by_address(source);
if (source_module == game)
{
context->ContextFlags &= ~debug_registers_flag;
}
}
return get_thread_context_hook.invoke<BOOL>(thread_handle, context);
}
utilities::hook::detour create_mutex_ex_a_hook;
HANDLE create_mutex_ex_a_stub(const LPSECURITY_ATTRIBUTES attributes, const LPCSTR name, const DWORD flags,
const DWORD access)
{
if (name == "$ IDA trusted_idbs"s || name == "$ IDA registry mutex $"s)
{
return nullptr;
}
return create_mutex_ex_a_hook.invoke<HANDLE>(attributes, name, flags, access);
}
bool remove_evil_keywords_from_string(const UNICODE_STRING& string)
{
static const std::wstring evil_keywords[] =
{
L"IDA",
L"ida",
L"HxD",
L"cheatengine",
L"Cheat Engine",
L"x96dbg",
L"x32dbg",
L"x64dbg",
L"Wireshark",
};
if (!string.Buffer || !string.Length)
{
return false;
}
const std::wstring_view path(string.Buffer, string.Length / sizeof(string.Buffer[0]));
bool modified = false;
for (const auto& keyword : evil_keywords)
{
while (true)
{
const auto pos = path.find(keyword);
if (pos == std::wstring::npos)
{
break;
}
modified = true;
for (size_t i = 0; i < keyword.size(); ++i)
{
string.Buffer[pos + i] = L'a';
}
}
}
return modified;
}
bool remove_evil_keywords_from_string(wchar_t* str, const size_t length)
{
UNICODE_STRING unicode_string{};
unicode_string.Buffer = str;
unicode_string.Length = static_cast<uint16_t>(length);
unicode_string.MaximumLength = unicode_string.Length;
return remove_evil_keywords_from_string(unicode_string);
}
bool remove_evil_keywords_from_string(char* str, const size_t length)
{
std::string_view str_view(str, length);
std::wstring wstr(str_view.begin(), str_view.end());
if (!remove_evil_keywords_from_string(wstr.data(), wstr.size()))
{
return false;
}
const std::string regular_str(wstr.begin(), wstr.end());
memcpy(str, regular_str.data(), length);
return true;
}
int WINAPI get_window_text_a_stub(const HWND wnd, const LPSTR str, const int max_count)
{
std::wstring wstr{};
wstr.resize(max_count);
const auto res = GetWindowTextW(wnd, wstr.data(), max_count);
if (res)
{
remove_evil_keywords_from_string(wstr.data(), res);
const std::string regular_str(wstr.begin(), wstr.end());
memset(str, 0, max_count);
memcpy(str, regular_str.data(), res);
}
return res;
}
utilities::hook::detour nt_query_system_information_hook;
NTSTATUS NTAPI nt_query_system_information_stub(const SYSTEM_INFORMATION_CLASS system_information_class,
const PVOID system_information,
const ULONG system_information_length,
const PULONG return_length)
{
const auto status = nt_query_system_information_hook.invoke<NTSTATUS>(
system_information_class, system_information, system_information_length, return_length);
if (NT_SUCCESS(status))
{
if (system_information_class == SystemProcessInformation && !utilities::nt::is_shutdown_in_progress())
{
auto addr = static_cast<uint8_t*>(system_information);
while (true)
{
const auto info = reinterpret_cast<SYSTEM_PROCESS_INFORMATION*>(addr);
remove_evil_keywords_from_string(info->ImageName);
if (!info->NextEntryOffset)
{
break;
}
addr = addr + info->NextEntryOffset;
}
}
}
return status;
}
utilities::hook::detour nt_query_information_process_hook;
NTSTATUS WINAPI nt_query_information_process_stub(const HANDLE handle, const PROCESSINFOCLASS info_class,
const PVOID info,
const ULONG info_length, const PULONG ret_length)
{
NTSTATUS status = nt_query_information_process_hook.invoke<NTSTATUS>(handle, info_class, info, info_length,
ret_length);
if (NT_SUCCESS(status))
{
if (info_class == ProcessImageFileName || static_cast<int>(info_class) == 43 /*ProcessImageFileNameWin32*/)
{
remove_evil_keywords_from_string(*static_cast<UNICODE_STRING*>(info));
}
}
return status;
}
}
class component final : public component_interface
{
public:
void pre_start() override
{
disable_tls_callbacks();
create_thread_hook.create(CreateThread, create_thread_stub);
auto* get_thread_context_func = utilities::nt::library("kernelbase.dll").get_proc<void*>("GetThreadContext");
get_thread_context_hook.create(get_thread_context_func, get_thread_context_stub);
create_mutex_ex_a_hook.create(CreateMutexExA, create_mutex_ex_a_stub);
utilities::hook::copy(this->window_text_buffer_, GetWindowTextA, sizeof(this->window_text_buffer_));
utilities::hook::jump(GetWindowTextA, get_window_text_a_stub, true, true);
utilities::hook::move_hook(GetWindowTextA);
const utilities::nt::library ntdll("ntdll.dll");
const auto nt_query_information_process = ntdll.get_proc<void*>("NtQueryInformationProcess");
nt_query_information_process_hook.create(nt_query_information_process,
nt_query_information_process_stub);
const auto nt_query_system_information = ntdll.get_proc<void*>("NtQuerySystemInformation");
nt_query_system_information_hook.create(nt_query_system_information, nt_query_system_information_stub);
nt_query_system_information_hook.move();
/*************************************************************************************************************
** TODO : There is some kind of dormant defence mechanism. works so random makes it harder to investigate
** It will Exit process with code zero in case gets induced mid-game or just prevent initialization
** causing to get black screened if tripped boot-time. Apparently it verifies IAT's integrity.
**
**
*************************************************************************************************************/
}
void post_unpack() override
{
search_and_patch_integrity_checks();
}
int priority() override
{
return 9999;
}
private:
uint8_t window_text_buffer_[15]{};
};
}
REGISTER_COMPONENT(arxan::component)