Windows Phone 8加载外部动态链接库DLL（非安装包内的）
在《动态加载与插件化》中大概介绍了下，wp8加载非安装包的下动态链接库，这次详细梳理下。
加载外部DLL主要的原理：
- 通过NtCurrentTeb获得线程环境块
- 从线程环境块中获得进程环境块
- 在进程环境块中加载过得DLL链表
- 从链表中找到kernelbase.dll的模块句柄
- 从kernelbase.dll中获得LoadLibraryEx函数地址
- 加载指定地址下的DLL
相关的结构体：
typedef struct _CLIENT_ID
{
PVOID UniqueProcess;
PVOID UniqueThread;
} CLIENT_ID;
//模块链表实体
typedef struct _MODULE_LIST_ENTRY
{
struct _MODULE_LIST_ENTRY* Flink;
struct _MODULE_LIST_ENTRY* Blink;
DWORD* baseAddress;
}MODULE_LIST_ENTRY;
//进程加载的模块信息
typedef struct _PEB_LDR_DATA
{
// BYTE fill[0x1c]; x86
ULONG Length;
BOOLEAN Initialized;
PVOID SsHandle ;
LIST_ENTRY InLoadOrderModuleList;
LIST_ENTRY InMemoryOrderModuleList;
MODULE_LIST_ENTRY* initModuleList;
}PEB_LDR_DATA;
//进程环境块
typedef struct _PEB
{
// BYTE fill[0x0c]; x86
BYTE Reserved1[2];
BYTE BeingDebugged;
BYTE Reserved2[1];
PVOID Reserved3[2];
PEB_LDR_DATA* ldr;
}PEB;
//线程环境块
typedef struct _TEB
{
//BYTE fill[0x30]; x86
NT_TIB nt_tib;
PVOID EnvironmentPointer;
CLIENT_ID id;
PVOID ActiveRpcHandle;
PVOID ThreadLocalStoragePointer;
PEB* currentPEB;
}TEB;
typedef HMODULE(*LoadLibraryEx)(
LPCTSTR lpLibFileName,
HANDLE hFile,
DWORD dwFlags
);
获取kernelbase.dll模块句柄的类定义
namespace Anye{ namespace Native { public ref class DllHandle sealed { friend ref class NativeInterop; friend class NativeHelper; public: int GetModule(); private: HMODULE _handle; DllHandle(HMODULE handle);
//获取指定名称的函数地址 void* GetFunction(LPCSTR name); }; public ref class NativeInterop sealed { public: NativeInterop(); //加载指定路径下的DLL
DllHandle^ LoadLibrary(Platform::String^ name);
//获取KernelBase.dll的模块句柄 DllHandle^ GetKernel(); int GetModule(); private: DllHandle^ _kernel; LoadLibraryEx _loadLibrary; HMODULE getKernelModule(); }; class NativeHelper { public: NativeHelper(const wchar_t* path); void* GetFunction(LPCSTR name); private: DllHandle^ _interop; };
}}主要的加载逻辑
HMODULE NativeInterop::getKernelModule(){
//获取线程环境快 TEB* teb = NtCurrentTeb(); 获取KernelBase.dll的模块句柄PS：保险点的方法市历遍DLL初始化链表通过模块名称确定 return (HMODULE) teb->currentPEB->ldr->initModuleList->Flink->baseAddress;}DllHandle^ NativeInterop::LoadLibrary(Platform::String^ name){ if (_loadLibrary == nullptr)//获取LoadLibraryExW函数地址 _loadLibrary = (LoadLibraryEx)_kernel->GetFunction("LoadLibraryExW");
HMODULE module = _loadLibrary(name->Data(), nullptr, 0); if (module != nullptr) return ref new DllHandle(module); return nullptr;}
void* DllHandle::GetFunction(LPCSTR name){ return GetProcAddress(_handle, name);}NativeHelper
NativeHelper::NativeHelper(const wchar_t* path){ auto inter = ref new NativeInterop(); String^ pathString = (Platform::String^)Platform::StringReference(path); _interop = inter->LoadLibrary(pathString);}void* NativeHelper::GetFunction(LPCSTR name){ return _interop->GetFunction(name);
}下面是加载wp手机SD卡上的plugin.dll的例子
动态库项目
动态链接库逻辑
extern "C"{ __declspec(dllexport) void* Create();}namespace Plugin{ class IPlugin { public: virtual void Show(Platform::String^ msg) = 0; }; class TestPlugin : public IPlugin { public: TestPlugin() { } void Show(Platform::String^ msg) { (ref new Windows::UI::Popups::MessageDialog(msg))->ShowAsync(); } };}void* Create(){ return new Plugin::TestPlugin();}加载外部动态链接库
class IPlugin{public: virtual void Show(Platform::String^ msg) = 0;};void NativeEntry::Load(Platform::String^ path){ //path 是 D:\\Downloads\\plugin.dll,D盘就是sd Anye::Native::NativeHelper* h = new Anye::Native::NativeHelper(path->Data()); CreateFunc func;
func = (CreateFunc)h->GetFunction("Create"); IPlugin* plugin = (IPlugin*)func(); plugin->Show("我是"+path+"里的插件^_^");}好了例子就到这了，我们获得了LoadLibraryExW函数，不局限于加载外部DLL，也可以去加载系统的DLL，去访问一些微软未公开的API，如只读访问注册表信息
Anye::Native::NativeInterop interop; auto h = interop.LoadLibrary("ADVAPI32LEGACY.DLL"); Anye_RegCreateKeyEx = (RegCreateKeyFunc)GetFunc(h->GetModule(), "RegCreateKeyW"); Anye_RegSetValueEx = (RegSetValueFunc)GetFunc(h->GetModule(), "RegSetValueW"); Anye_RegQueryValueEx = (RegQueryValueFunc)GetFunc(h->GetModule(), "RegQueryValueW"); Anye_RegCloseKey = (RegCloseKeyFunc)GetFunc(h->GetModule(), "RegCloseKey"); Anye_RegOpenKey = (RegOpenKeyFunc)GetFunc(h->GetModule(), "RegOpenKeyW"); Anye_RegEnumKey = (RegEnumKeyFunc)GetFunc(h->GetModule(), "RegEnumKeyW");