Textractor/texthook/engine/match64.cc

#include "match.h"
#include "main.h"
#include "texthook.h"
#include "native/pchooks.h"
#include "mono/monoobject.h"
#include "mono/funcinfo.h"
#include "engine.h"
#include "util.h"

namespace Engine
{
	/** Artikash 6/7/2019
*   PPSSPP JIT code has pointers, but they are all added to an offset before being used.
	Find that offset so that hook searching works properly.
	To find the offset, find a page of mapped memory with size 0x1f00000, read and write permissions, take its address and subtract 0x8000000.
	The above is useful for emulating PSP hardware, so unlikely to change between versions.
*/
	bool FindPPSSPP()
	{
		bool found = false;
		SYSTEM_INFO systemInfo;
		GetNativeSystemInfo(&systemInfo);
		for (BYTE* probe = NULL; probe < systemInfo.lpMaximumApplicationAddress;)
		{
			MEMORY_BASIC_INFORMATION info;
			if (!VirtualQuery(probe, &info, sizeof(info)))
			{
				probe += systemInfo.dwPageSize;
			}
			else
			{
				if (info.RegionSize == 0x1f00000 && info.Protect == PAGE_READWRITE && info.Type == MEM_MAPPED)
				{
					found = true;
					ConsoleOutput("Textractor: PPSSPP memory found: searching for hooks should yield working hook codes");
					// PPSSPP 1.8.0 compiles jal to sub dword ptr [r14+0x360],??
					memcpy(spDefault.pattern, Array<BYTE>{ 0x41, 0x83, 0xae, 0x60, 0x03, 0x00, 0x00 }, spDefault.length = 7);
					spDefault.offset = 0;
					spDefault.minAddress = 0;
					spDefault.maxAddress = -1ULL;
					spDefault.padding = (uintptr_t)probe - 0x8000000;
					spDefault.hookPostProcessor = [](HookParam& hp)
					{
						hp.type |= NO_CONTEXT | USING_SPLIT | SPLIT_INDIRECT;
						hp.split = -0x80; // r14
						hp.split_index = -8; // this is where PPSSPP 1.8.0 stores its return address stack
					};
				}
				probe += info.RegionSize;
			}
		}
		return found;
	}

	bool InsertMonoHooks(HMODULE module)
	{
		auto SpecialHookMonoString = nullptr;
		static HMODULE mono = module;
		bool ret = false;
		for (auto func : Array<MonoFunction>{ MONO_FUNCTIONS_INITIALIZER })
		{
			HookParam hp = {};
			if (!(hp.address = (uintptr_t)GetProcAddress(mono, func.functionName))) continue;
			hp.type = HOOK_EMPTY;
			NewHook(hp, "Mono Searcher");
			ret = true;
		}
		/* Artikash 2/13/2019:
		How to hook Mono/Unity3D:
		Find all standard function prologs in memory with write/execute permission: these represent possible JIT compiled functions
		Then use Mono APIs to reflect what these functions are, and hook them if they are string member functions
		Mono calling convention uses 'this' as first argument
		Must be dynamic hook bootstrapped from other mono api or mono_domain_get won't work
		*/
		trigger_fun = [](LPVOID addr, DWORD, DWORD)
		{
			static auto getDomain = (MonoDomain*(*)())GetProcAddress(mono, "mono_domain_get");
			static auto getJitInfo = (MonoObject*(*)(MonoDomain*, uintptr_t))GetProcAddress(mono, "mono_jit_info_table_find");
			static auto getName = (char*(*)(uintptr_t))GetProcAddress(mono, "mono_pmip");
			if (!getDomain || !getName || !getJitInfo) goto failed;
			static auto domain = getDomain();
			if (!domain) goto failed;
			ConsoleOutput("Textractor: Mono Dynamic ENTER (hooks = %s)", loadedConfig ? loadedConfig : "brute force");
			const BYTE prolog1[] = { 0x55, 0x48, 0x8b, 0xec };
			const BYTE prolog2[] = { 0x48, 0x83, 0xec };
			for (auto [prolog, size] : Array<const BYTE*, size_t>{ { prolog1, sizeof(prolog1) }, { prolog2, sizeof(prolog2) } })
			for (auto addr : Util::SearchMemory(prolog, size, PAGE_EXECUTE_READWRITE))
			{
				[](uint64_t addr)
				{
					__try
					{
						if (getJitInfo(domain, addr))
							if (char* name = getName(addr))
								if (strstr(name, "0x0") && ShouldMonoHook(name))
								{
									HookParam hp = {};
									hp.address = addr;
									hp.type = USING_STRING | USING_UNICODE | FULL_STRING;
									if (!loadedConfig) hp.type |= KNOWN_UNSTABLE;
									hp.offset = -0x20; // rcx
									hp.padding = 20;
									char nameForUser[HOOK_NAME_SIZE] = {};
									strncpy_s(nameForUser, name + 1, HOOK_NAME_SIZE - 1);
									if (char* end = strstr(nameForUser, " + 0x0")) *end = 0;
									if (char* end = strstr(nameForUser, "{")) *end = 0;
									hp.length_fun = [](uintptr_t, uintptr_t data)
									{
										/* Artikash 6/18/2019:
										even though this should get the true length mono uses internally
										there's still some garbage picked up on https://vndb.org/v20403 demo, don't know why */
										int len = *(int*)(data - 4);
										return len > 0 && len < PIPE_BUFFER_SIZE ? len * 2 : 0;
									};
									NewHook(hp, nameForUser);
								}
					}
					__except (EXCEPTION_EXECUTE_HANDLER) {}
				}(addr);
			}

			if (!loadedConfig) ConsoleOutput("Textractor: Mono Dynamic used brute force: if performance issues arise, please specify the correct hook in the game configuration");
			return true;
		failed:
			ConsoleOutput("Textractor: Mono Dynamic failed");
			return true;
		};
		return ret;
	}

	// Artikash 6/23/2019: V8 (JavaScript runtime) has rcx = string** at v8::String::Write
	// sample game https://www.freem.ne.jp/dl/win/18963
	bool InsertV8Hook(HMODULE module)
	{
		if (uint64_t addr = (uint64_t)GetProcAddress(module, "?Write@String@v8@@QEBAHPEAGHHH@Z"))
		{
			std::tie(spDefault.minAddress, spDefault.maxAddress) = Util::QueryModuleLimits(module);
			spDefault.maxRecords = Util::SearchMemory(spDefault.pattern, spDefault.length, PAGE_EXECUTE, spDefault.minAddress, spDefault.maxAddress).size() * 20;
			ConsoleOutput("Textractor: JavaScript hook is known to be low quality: try searching for hooks if you don't like it");
			HookParam hp = {};
			hp.type = USING_STRING | USING_UNICODE | DATA_INDIRECT;
			hp.address = addr;
			hp.offset = -0x20; // rcx
			hp.index = 0;
			hp.padding = 23;
			hp.length_fun = [](uintptr_t, uintptr_t data)
			{
				int len = *(int*)(data - 4);
				return len > 0 && len < PIPE_BUFFER_SIZE ? len * 2 : 0;
			};
			NewHook(hp, "JavaScript");
			return true;
		}
		return false;
	}

	/** Artikash 8/10/2018: Ren'py
	*
	*  Sample games: https://vndb.org/v19843 https://vndb.org/v12038 and many more OELVNs
	*
	*  Uses CPython, and links to python27.dll. PyUicodeUCS2_Format is the function used to process text.
	*  first argument. offset 0x18 from that is a wchar_t* to the actual string
	*  ebx seems to work well as the split param, not sure why
	*/
	bool InsertRenpyHook()
	{
		wchar_t python[] = L"python2X.dll", libpython[] = L"libpython2.X.dll";
		for (wchar_t* name : { python, libpython })
		{
			wchar_t* pos = wcschr(name, L'X');
			for (int pythonMinorVersion = 0; pythonMinorVersion <= 8; ++pythonMinorVersion)
			{
				*pos = L'0' + pythonMinorVersion;
				if (HMODULE module = GetModuleHandleW(name))
				{
					wcscpy_s(spDefault.exportModule, name);
					HookParam hp = {};
					hp.address = (DWORD)GetProcAddress(module, "PyUnicodeUCS2_Format");
					if (!hp.address)
					{
						ConsoleOutput("Textractor: Ren'py failed: failed to find PyUnicodeUCS2_Format");
						return false;
					}
					hp.offset = -0x20; // rcx
					hp.index = 0x18;
					hp.length_offset = 0;
					//hp.split = pusha_ebx_off - 4;
					hp.type = USING_STRING | USING_UNICODE | NO_CONTEXT | DATA_INDIRECT /* | USING_SPLIT*/;
					//hp.filter_fun = [](void* str, auto, auto, auto) { return *(wchar_t*)str != L'%'; };
					NewHook(hp, "Ren'py");
					return true;
				}
			}
		}
		ConsoleOutput("Textractor: Ren'py failed: failed to find python2X.dll");
		return false;
	}

	bool UnsafeDetermineEngineType()
	{
		if (Util::CheckFile(L"PPSSPP*.exe") && FindPPSSPP()) return true;

		for (const wchar_t* moduleName : { (const wchar_t*)NULL, L"node.dll", L"nw.dll" }) if (InsertV8Hook(GetModuleHandleW(moduleName))) return true;

		if (GetModuleHandleW(L"GameAssembly.dll")) // TODO: is there a way to autofind hook?
		{
			ConsoleOutput("Textractor: Precompiled Unity found (searching for hooks should work)");
			wcscpy_s(spDefault.boundaryModule, L"GameAssembly.dll");
			spDefault.padding = 20;
			return true;
		}

		if (Util::CheckFile(L"*.py") && InsertRenpyHook()) return true;

		for (const wchar_t* monoName : { L"mono.dll", L"mono-2.0-bdwgc.dll" }) if (HMODULE module = GetModuleHandleW(monoName)) if (InsertMonoHooks(module)) return true;

		for (std::wstring DXVersion : { L"d3dx9", L"d3dx10" })
			if (HMODULE module = GetModuleHandleW(DXVersion.c_str())) PcHooks::hookD3DXFunctions(module);
			else for (int i = 0; i < 50; ++i)
				if (HMODULE module = GetModuleHandleW((DXVersion + L"_" + std::to_wstring(i)).c_str())) PcHooks::hookD3DXFunctions(module);

		PcHooks::hookGDIFunctions();
		PcHooks::hookGDIPlusFunctions();
		return false;
	}
}