Add DLL to modify PlayFab url

src/Prospect.Agent/main.cpp

@@ -1,17 +1,71 @@
+#define WIN32_LEAN_AND_MEAN
+#include <Windows.h>
+#include <MinHook.h>
 #include <cstdio>
-#include "main.h"
 #include "logger.h"
-#include <detours.h>
+#include "SDK.h"
+#include "SDK_Memory.h"
+
+/**
+ * Variable offset, find with "STOPMOVIECAPTURE", scroll up.
+ */
+constexpr uintptr_t OffsetGMalloc = 0x5C9A3F8;
+
+/**
+ * Function offset, find with "?sdk=".
+ */
+constexpr uintptr_t OffsetPlayFabApiGetUrl = 0xCA5010;
+
+/**
+ * Function hooks.
+ */
+typedef SDK::FString(__fastcall* tPlayFabApiGetUrl)(SDK::UPlayFabAPISettings*, const SDK::FString&);
+
+tPlayFabApiGetUrl OldPlayFabApiGetUrl;
+
+SDK::FString __fastcall PlayFabApiGetUrlProxy(SDK::UPlayFabAPISettings* thiz, const SDK::FString& callPath)
+{
+	logger::Print("[Agent] GetURL called with callPath %s\n", callPath.ToString().c_str());
+	
+	return std::wstring(L"http://127.0.0.1:8888") + std::wstring(callPath.c_str());
+}
 
 DWORD WINAPI OnDllAttach(LPVOID base)
 {
-	logger::Attach();
 	logger::Print("[Agent] DLL Attached\n");
 
-	// TODO: Patch.
+	const auto hModule = GetModuleHandleW(nullptr);
+	const auto hModulePtr = reinterpret_cast<uintptr_t>(hModule);
 
-	logger::Print("[Agent] DLL Exit\n");
-	FreeLibraryAndExitThread(static_cast<HMODULE>(base), 1);
+	// Initialize GMalloc.
+	SDK::GMalloc = *reinterpret_cast<SDK::FMalloc**>(hModulePtr + OffsetGMalloc);
+
+	// Initialize MinHook.
+	if (MH_Initialize() != MH_OK)
+	{
+		logger::Print("[Agent] Failed to initialize MinHook\n");
+		FreeLibraryAndExitThread(hModule, 1);
+	}
+
+	// Hook UPlayFabAPISettings::GetUrl.
+	const auto pTarget = reinterpret_cast<LPVOID>(hModulePtr + OffsetPlayFabApiGetUrl);
+	const auto ppOriginal = reinterpret_cast<LPVOID*>(&OldPlayFabApiGetUrl);
+	const auto mhStatus = MH_CreateHook(pTarget, &PlayFabApiGetUrlProxy, ppOriginal);
+
+	if (mhStatus != MH_OK)
+	{
+		logger::Print("[Agent] Failed to create PlayFabAPIGetUrl hook (%d)\n", mhStatus);
+		FreeLibraryAndExitThread(hModule, 1);
+	}
+
+	if (MH_EnableHook(pTarget) != MH_OK)
+	{
+		logger::Print("[Agent] Failed to enable PlayFabAPIGetUrl hook\n");
+		FreeLibraryAndExitThread(hModule, 1);
+	}
+
+	logger::Print("[Agent] DLL Initialized\n");
+	ExitThread(1);
 }
 
 BOOL WINAPI DllMain(
@@ -27,10 +81,18 @@ BOOL WINAPI DllMain(
 		// Allocate a console.
 		AllocConsole();
 		freopen_s(reinterpret_cast<FILE**>(stdout), "CONOUT$", "w", stdout);
+
+		// Attach logger.
+		logger::Attach();
 		
 		// Spawn thread.
 		CreateThread(nullptr, 0, OnDllAttach, hinstDll, 0, nullptr);
 	}
+	else if (fdwReason == DLL_PROCESS_DETACH)
+	{
+		// Detach logger.
+		logger::Detach();
+	}
 
     return TRUE;
 }