cube

CubeModLoader/DLL.cpp

@@ -0,0 +1,16 @@
+#include "DLL.h"
+#include <iostream>
+
+DLL::DLL(std::string fileName) {
+    this->fileName = fileName;
+    this->handle = nullptr;
+}
+
+HMODULE DLL::Load() {
+    this->handle = LoadLibraryA(this->fileName.c_str());
+    return this->handle;
+}
+
+DLL::~DLL() {
+    //dtor
+}

CubeModLoader/DLL.h

@@ -0,0 +1,28 @@
+#ifndef DLL_H
+#define DLL_H
+#include <iostream>
+#include <windows.h>
+
+class DLL
+{
+    public:
+        std::string fileName;
+        HMODULE handle;
+
+        FARPROC ModInitialize;
+        FARPROC ModMajorVersion;
+        FARPROC ModMinorVersion;
+
+        // Callbacks
+        FARPROC HandleNumber;
+
+        DLL(std::string fileName);
+        HMODULE Load();
+        virtual ~DLL();
+
+    protected:
+
+    private:
+};
+
+#endif // DLL_H

CubeModLoader/main.cpp

@@ -1,15 +1,95 @@
 #include <iostream>
 #include <windows.h>
 #include <vector>
+#include "DLL.h"
+
+#define MOD_MAJOR_VERSION 1
+#define MOD_MINOR_VERSION 1
+
+
+#define no_optimize __attribute__((optimize("O0")))
+
+#define MUST_IMPORT(dllname, name)\
+dllname->name = GetProcAddress(dllname->handle, #name);\
+            if (!dllname->name) {\
+                printf("%s does not export " #name ".\n", dllname->fileName.c_str());\
+                exit(1);\
+            }
+
+#define IMPORT(dllname, name)\
+dllname->name = GetProcAddress(dllname->handle, #name);
+
 
 using namespace std;
 
+void* base;
+vector <DLL*> modDLLs;
+
+void WriteFarJMP(void* source, void* destination) {
+    DWORD dwOldProtection;
+    VirtualProtect(source, 14, PAGE_EXECUTE_READWRITE, &dwOldProtection);
+    char* location = (char*)source;
+
+    // Far jump
+    *((UINT16*)&location[0]) = 0x25FF;
+
+    // mode
+    *((UINT32*)&location[2]) = 0x00000000;
+
+    *((UINT64*)&location[6]) = (UINT64)destination;
+
+    VirtualProtect(location, 14, dwOldProtection, &dwOldProtection);
+}
+
+
+
+// Example handler
+void NumberHandler(int number) {
+    for (DLL* dll: modDLLs) {
+        if (dll->HandleNumber) {
+            ((void(*)(int))dll->HandleNumber)(number);
+        }
+    }
+}
+void* NumberHandler_ptr = (void*)&NumberHandler;
+
+void* ASMNumberHandler_jmpback;
+char ASMNumberHandler_formatstring[] = "%d...\n";
+void no_optimize ASMNumberHandler() {
+    asm("call rax \n"
+        "mov eax, [rbp-4] \n"
+        "push rax\n push rcx\n push rdx\n push r8\n push r9\n push r10\n push r11\n"
+
+        "sub rsp, 0x20 \n"
+        "mov ecx, eax \n"
+        "call [NumberHandler_ptr] \n"
+        "add rsp, 0x20 \n"
+
+        "pop r11\n pop r10\n pop r9\n pop r8\n pop rdx\n pop rcx\n pop rax\n"
+
+        "mov edx, eax \n"
+        "lea rcx, [ASMNumberHandler_formatstring] \n"
+        "jmp [ASMNumberHandler_jmpback]"
+       );
+}
+void SetupNumberHandler() {
+    WriteFarJMP(base+0x1597, (void*)&ASMNumberHandler);
+    ASMNumberHandler_jmpback = (void*)base+0x15A5;
+}
+
+
+void SetupHandlers() {
+    SetupNumberHandler();
+}
+
 extern "C" __declspec(dllexport) BOOL APIENTRY DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved) {
     switch (fdwReason) {
     case DLL_PROCESS_ATTACH:
-        MessageBoxA(0, "hello!", "DLL Message", MB_OK | MB_ICONINFORMATION);
+        base = GetModuleHandle(NULL);
 
-        vector <std::string> modDLLs;
+        SetupHandlers();
+
+        MessageBoxA(0, "hello!", "DLL Message", MB_OK | MB_ICONINFORMATION);
 
         //Find mods
         HANDLE hFind;
@@ -19,15 +99,28 @@ extern "C" __declspec(dllexport) BOOL APIENTRY DllMain(HINSTANCE hinstDLL, DWORD
         hFind = FindFirstFile("Mods\\*.dll", &data);
         if (hFind != INVALID_HANDLE_VALUE) {
             do {
-                modDLLs.push_back( std::string("Mods\\") + data.cFileName);
+                // We should be loaded into the application's address space, so we can just LoadLibraryA
+                DLL* dll = new DLL(string("Mods\\") + data.cFileName);
+                dll->Load();
+                modDLLs.push_back(dll);
             } while (FindNextFile(hFind, &data));
             FindClose(hFind);
         }
 
-        // We should be loaded into the application's address space, so we can just LoadLibraryA
-        for (std::string modName : modDLLs) {
-            LoadLibraryA(modName.c_str());
+
+        // Find all the functions the mods may export
+        for (DLL* dll: modDLLs) {
+            MUST_IMPORT(dll, ModMajorVersion);
+            MUST_IMPORT(dll, ModMinorVersion);
+            MUST_IMPORT(dll, ModInitialize);
+            IMPORT(dll, HandleNumber);
         }
+
+        // Run Initialization routines on all mods
+        for (DLL* dll: modDLLs) {
+            ((void(*)())dll->ModInitialize)();
+        }
+
     }
     return true;
 }