驱动开发:内核通过PEB得到进程参数

PEB结构(Process Envirorment Block Structure)其中文名是进程环境块信息,进程环境块内部包含了进程运行的详细参数信息,每一个进程在运行后都会存在一个特有的PEB结构,通过附加进程并遍历这段结构即可得到非常多的有用信息。

在应用层下,如果想要得到PEB的基地址只需要取fs:[0x30]即可,TEB线程环境块则是fs:[0x18],如果在内核层想要得到应用层进程的PEB信息我们需要调用特定的内核函数来获取,如下案例将教大家如何在内核层取到应用层进程的PEB结构。

首先在开始写代码之前需要先定义好PEB进程环境快结构体,用于对内存指针解析,新建peb.h文件并保存如下代码,这些是微软的结构定义分为32位与64位,官方定义规范而已不需要费工夫。

#pragma once
#include <ntifs.h>

typedef struct _CURDIR // 2 elements, 0x18 bytes (sizeof)
{
/*0x000*/ struct _UNICODE_STRING DosPath; // 3 elements, 0x10 bytes (sizeof)
/*0x010*/ VOID* Handle;
}CURDIR, *PCURDIR;

typedef struct _RTL_DRIVE_LETTER_CURDIR // 4 elements, 0x18 bytes (sizeof)
{
/*0x000*/ UINT16 Flags;
/*0x002*/ UINT16 Length;
/*0x004*/ ULONG32 TimeStamp;
/*0x008*/ struct _STRING DosPath; // 3 elements, 0x10 bytes (sizeof)
}RTL_DRIVE_LETTER_CURDIR, *PRTL_DRIVE_LETTER_CURDIR;

typedef enum _SYSTEM_DLL_TYPE // 7 elements, 0x4 bytes
{
PsNativeSystemDll = 0 /*0x0*/,
PsWowX86SystemDll = 1 /*0x1*/,
PsWowArm32SystemDll = 2 /*0x2*/,
PsWowAmd64SystemDll = 3 /*0x3*/,
PsWowChpeX86SystemDll = 4 /*0x4*/,
PsVsmEnclaveRuntimeDll = 5 /*0x5*/,
PsSystemDllTotalTypes = 6 /*0x6*/
}SYSTEM_DLL_TYPE, *PSYSTEM_DLL_TYPE;

typedef struct _EWOW64PROCESS // 3 elements, 0x10 bytes (sizeof)
{
/*0x000*/ VOID* Peb;
/*0x008*/ UINT16 Machine;
/*0x00A*/ UINT8 _PADDING0_[0x2];
/*0x00C*/ enum _SYSTEM_DLL_TYPE NtdllType;
}EWOW64PROCESS, *PEWOW64PROCESS;

typedef struct _RTL_USER_PROCESS_PARAMETERS // 37 elements, 0x440 bytes (sizeof)
{
/*0x000*/ ULONG32 MaximumLength;
/*0x004*/ ULONG32 Length;
/*0x008*/ ULONG32 Flags;
/*0x00C*/ ULONG32 DebugFlags;
/*0x010*/ VOID* ConsoleHandle;
/*0x018*/ ULONG32 ConsoleFlags;
/*0x01C*/ UINT8 _PADDING0_[0x4];
/*0x020*/ VOID* StandardInput;
/*0x028*/ VOID* StandardOutput;
/*0x030*/ VOID* StandardError;
/*0x038*/ struct _CURDIR CurrentDirectory; // 2 elements, 0x18 bytes (sizeof)
/*0x050*/ struct _UNICODE_STRING DllPath; // 3 elements, 0x10 bytes (sizeof)
/*0x060*/ struct _UNICODE_STRING ImagePathName; // 3 elements, 0x10 bytes (sizeof)
/*0x070*/ struct _UNICODE_STRING CommandLine; // 3 elements, 0x10 bytes (sizeof)
/*0x080*/ VOID* Environment;
/*0x088*/ ULONG32 StartingX;
/*0x08C*/ ULONG32 StartingY;
/*0x090*/ ULONG32 CountX;
/*0x094*/ ULONG32 CountY;
/*0x098*/ ULONG32 CountCharsX;
/*0x09C*/ ULONG32 CountCharsY;
/*0x0A0*/ ULONG32 FillAttribute;
/*0x0A4*/ ULONG32 WindowFlags;
/*0x0A8*/ ULONG32 ShowWindowFlags;
/*0x0AC*/ UINT8 _PADDING1_[0x4];
/*0x0B0*/ struct _UNICODE_STRING WindowTitle; // 3 elements, 0x10 bytes (sizeof)
/*0x0C0*/ struct _UNICODE_STRING DesktopInfo; // 3 elements, 0x10 bytes (sizeof)
/*0x0D0*/ struct _UNICODE_STRING ShellInfo; // 3 elements, 0x10 bytes (sizeof)
/*0x0E0*/ struct _UNICODE_STRING RuntimeData; // 3 elements, 0x10 bytes (sizeof)
/*0x0F0*/ struct _RTL_DRIVE_LETTER_CURDIR CurrentDirectores[32];
/*0x3F0*/ UINT64 EnvironmentSize;
/*0x3F8*/ UINT64 EnvironmentVersion;
/*0x400*/ VOID* PackageDependencyData;
/*0x408*/ ULONG32 ProcessGroupId;
/*0x40C*/ ULONG32 LoaderThreads;
/*0x410*/ struct _UNICODE_STRING RedirectionDllName; // 3 elements, 0x10 bytes (sizeof)
/*0x420*/ struct _UNICODE_STRING HeapPartitionName; // 3 elements, 0x10 bytes (sizeof)
/*0x430*/ UINT64* DefaultThreadpoolCpuSetMasks;
/*0x438*/ ULONG32 DefaultThreadpoolCpuSetMaskCount;
/*0x43C*/ UINT8 _PADDING2_[0x4];
}RTL_USER_PROCESS_PARAMETERS, *PRTL_USER_PROCESS_PARAMETERS;

typedef struct _PEB_LDR_DATA // 9 elements, 0x58 bytes (sizeof)
{
/*0x000*/ ULONG32 Length;
/*0x004*/ UINT8 Initialized;
/*0x005*/ UINT8 _PADDING0_[0x3];
/*0x008*/ VOID* SsHandle;
/*0x010*/ struct _LIST_ENTRY InLoadOrderModuleList; // 2 elements, 0x10 bytes (sizeof)
/*0x020*/ struct _LIST_ENTRY InMemoryOrderModuleList; // 2 elements, 0x10 bytes (sizeof)
/*0x030*/ struct _LIST_ENTRY InInitializationOrderModuleList; // 2 elements, 0x10 bytes (sizeof)
/*0x040*/ VOID* EntryInProgress;
/*0x048*/ UINT8 ShutdownInProgress;
/*0x049*/ UINT8 _PADDING1_[0x7];
/*0x050*/ VOID* ShutdownThreadId;
}PEB_LDR_DATA, *PPEB_LDR_DATA;

typedef struct _PEB64
{
UCHAR InheritedAddressSpace;
UCHAR ReadImageFileExecOptions;
UCHAR BeingDebugged;
UCHAR BitField;
ULONG64 Mutant;
ULONG64 ImageBaseAddress;
PPEB_LDR_DATA Ldr;
PRTL_USER_PROCESS_PARAMETERS ProcessParameters;
ULONG64 SubSystemData;
ULONG64 ProcessHeap;
ULONG64 FastPebLock;
ULONG64 AtlThunkSListPtr;
ULONG64 IFEOKey;
ULONG64 CrossProcessFlags;
ULONG64 UserSharedInfoPtr;
ULONG SystemReserved;
ULONG AtlThunkSListPtr32;
ULONG64 ApiSetMap;
} PEB64, *PPEB64;

#pragma pack(4)
typedef struct _PEB32
{
UCHAR InheritedAddressSpace;
UCHAR ReadImageFileExecOptions;
UCHAR BeingDebugged;
UCHAR BitField;
ULONG Mutant;
ULONG ImageBaseAddress;
ULONG Ldr;
ULONG ProcessParameters;
ULONG SubSystemData;
ULONG ProcessHeap;
ULONG FastPebLock;
ULONG AtlThunkSListPtr;
ULONG IFEOKey;
ULONG CrossProcessFlags;
ULONG UserSharedInfoPtr;
ULONG SystemReserved;
ULONG AtlThunkSListPtr32;
ULONG ApiSetMap;
} PEB32, *PPEB32;

typedef struct _PEB_LDR_DATA32
{
ULONG Length;
BOOLEAN Initialized;
ULONG SsHandle;
LIST_ENTRY32 InLoadOrderModuleList;
LIST_ENTRY32 InMemoryOrderModuleList;
LIST_ENTRY32 InInitializationOrderModuleList;
ULONG EntryInProgress;
} PEB_LDR_DATA32, *PPEB_LDR_DATA32;

typedef struct _LDR_DATA_TABLE_ENTRY32
{
LIST_ENTRY32 InLoadOrderLinks;
LIST_ENTRY32 InMemoryOrderModuleList;
LIST_ENTRY32 InInitializationOrderModuleList;
ULONG DllBase;
ULONG EntryPoint;
ULONG SizeOfImage;
UNICODE_STRING32 FullDllName;
UNICODE_STRING32 BaseDllName;
ULONG Flags;
USHORT LoadCount;
USHORT TlsIndex;
union
{
LIST_ENTRY32 HashLinks;
ULONG SectionPointer;
}u1;
ULONG CheckSum;
union
{
ULONG TimeDateStamp;
ULONG LoadedImports;
}u2;
ULONG EntryPointActivationContext;
ULONG PatchInformation;
} LDR_DATA_TABLE_ENTRY32, *PLDR_DATA_TABLE_ENTRY32;

#pragma pack()

接着就来实现对PEB的获取操作,以64位为例,我们需要调用PsGetProcessPeb()这个内核函数,因为该内核函数没有被公开所以调用之前需要头部导出,该函数需要传入用户进程的EProcess结构,该结构可用PsLookupProcessByProcessId函数动态获取到,获取到以后直接KeStackAttachProcess()附加到应用层进程上,即可直接输出进程的PEB结构信息,如下代码。

#include "peb.h"
#include <ntifs.h>

// 定义导出
NTKERNELAPI PVOID NTAPI PsGetProcessPeb(_In_ PEPROCESS Process);

VOID UnDriver(PDRIVER_OBJECT driver)
{
DbgPrint(("Uninstall Driver Is OK \n"));
}
// LyShark
NTSTATUS DriverEntry(IN PDRIVER_OBJECT Driver, PUNICODE_STRING RegistryPath)
{
DbgPrint("hello lyshark \n");

NTSTATUS status = STATUS_UNSUCCESSFUL;
PEPROCESS eproc = NULL;
KAPC_STATE kpc = { 0 };

PPEB64 pPeb64 = NULL;

__try
{
// HANDLE)4656 进程PID
status = PsLookupProcessByProcessId((HANDLE)4656, &eproc);

// 得到64位PEB
pPeb64 = (PPEB64)PsGetProcessPeb(eproc);

DbgPrint("PEB64 = %p \n", pPeb64);

if (pPeb64 != 0)
{
// 验证可读性
ProbeForRead(pPeb64, sizeof(PEB32), 1);

// 附加进程
KeStackAttachProcess(eproc, &kpc);

DbgPrint("进程基地址: 0x%p \n", pPeb64->ImageBaseAddress);
DbgPrint("ProcessHeap = 0x%p \n", pPeb64->ProcessHeap);
DbgPrint("BeingDebugged = %d \n", pPeb64->BeingDebugged);

// 脱离进程
KeUnstackDetachProcess(&kpc);
}
}
__except (EXCEPTION_EXECUTE_HANDLER)
{
Driver->DriverUnload = UnDriver;
return STATUS_SUCCESS;
}

Driver->DriverUnload = UnDriver;
return STATUS_SUCCESS;
}

PEB64代码运行后,我们加载驱动即可看到如下结果:

而相对于64位进程来说,获取32位进程的PEB信息可以直接调用PsGetProcessWow64Process()函数得到,该函数已被导出可以任意使用,获取PEB代码如下。

#include "peb.h"
#include <ntifs.h>

// 定义导出
NTKERNELAPI PVOID NTAPI PsGetProcessPeb(_In_ PEPROCESS Process);

VOID UnDriver(PDRIVER_OBJECT driver)
{
DbgPrint(("Uninstall Driver Is OK \n"));
}

// LyShark
NTSTATUS DriverEntry(IN PDRIVER_OBJECT Driver, PUNICODE_STRING RegistryPath)
{
DbgPrint("hello lyshark \n");

NTSTATUS status = STATUS_UNSUCCESSFUL;
PEPROCESS eproc = NULL;
KAPC_STATE kpc = { 0 };

PPEB32 pPeb32 = NULL;

__try
{
// HANDLE)4656 进程PID
status = PsLookupProcessByProcessId((HANDLE)6164, &eproc);

// 得到32位PEB
pPeb32 = (PPEB32)PsGetProcessWow64Process(eproc);

DbgPrint("PEB32 = %p \n", pPeb32);

if (pPeb32 != 0)
{
// 验证可读性
ProbeForRead(pPeb32, sizeof(PEB32), 1);

// 附加进程
KeStackAttachProcess(eproc, &kpc);

DbgPrint("进程基地址: 0x%p \n", pPeb32->ImageBaseAddress);
DbgPrint("ProcessHeap = 0x%p \n", pPeb32->ProcessHeap);
DbgPrint("BeingDebugged = %d \n", pPeb32->BeingDebugged);

// 脱离进程
KeUnstackDetachProcess(&kpc);
}

}
__except (EXCEPTION_EXECUTE_HANDLER)
{
Driver->DriverUnload = UnDriver;
return STATUS_SUCCESS;
}

Driver->DriverUnload = UnDriver;
return STATUS_SUCCESS;
}

PEB32代码运行后,我们加载驱动即可看到如下结果: