interface

uses windows;

function MemExecute(const ABuffer; Len: Integer; CmdParam: string; var ProcessId: Cardinal): Cardinal;

implementation

//{$R ExeShell.res} // 外壳程序模板(98下使用)

type

TImageSectionHeaders = array [0..0] of TImageSectionHeader;

PImageSectionHeaders = ^TImageSectionHeaders;

{ 计算对齐后的大小 }

function GetAlignedSize(Origin, Alignment: Cardinal): Cardinal;

begin

result := (Origin + Alignment - 1) div Alignment * Alignment;

end;

{ 计算加载pe并对齐需要占用多少内存，未直接使用OptionalHeader.SizeOfImage作为结果是因为据说有的编译器生成的exe这个值会填0 }

function CalcTotalImageSize(MzH: PImageDosHeader; FileLen: Cardinal; peH: PImageNtHeaders;

peSecH: PImageSectionHeaders): Cardinal;

var

i: Integer;

begin

{计算pe头的大小}

result := GetAlignedSize(PeH.OptionalHeader.SizeOfHeaders, PeH.OptionalHeader.SectionAlignment);

{计算所有节的大小}

for i := 0 to peH.FileHeader.NumberOfSections - 1 do

if peSecH[i].PointerToRawData + peSecH[i].SizeOfRawData > FileLen then // 超出文件范围

begin

result := 0;

exit;

end

else if peSecH[i].VirtualAddress <> 0 then //计算对齐后某节的大小

if peSecH[i].Misc.VirtualSize <> 0 then

result := GetAlignedSize(peSecH[i].VirtualAddress + peSecH[i].Misc.VirtualSize, PeH.OptionalHeader.SectionAlignment)

else

result := GetAlignedSize(peSecH[i].VirtualAddress + peSecH[i].SizeOfRawData, PeH.OptionalHeader.SectionAlignment)

else if peSecH[i].Misc.VirtualSize < peSecH[i].SizeOfRawData then

result := result + GetAlignedSize(peSecH[i].SizeOfRawData, peH.OptionalHeader.SectionAlignment)

else

result := result + GetAlignedSize(peSecH[i].Misc.VirtualSize, PeH.OptionalHeader.SectionAlignment);

end;

{ 加载pe到内存并对齐所有节 }

function AlignPEToMem(const Buf; Len: Integer; var PeH: PImageNtHeaders;

var PeSecH: PImageSectionHeaders; var Mem: Pointer; var ImageSize: Cardinal): Boolean;

var

SrcMz: PImageDosHeader; // DOS头

SrcPeH: PImageNtHeaders; // PE头

SrcPeSecH: PImageSectionHeaders; // 节表

i: Integer;

l: Cardinal;

Pt: Pointer;

begin

result := false;

SrcMz := @Buf;

if Len < sizeof(TImageDosHeader) then exit;

if SrcMz.e_magic <> IMAGE_DOS_SIGNATURE then exit;

if Len < SrcMz._lfanew+Sizeof(TImageNtHeaders) then exit;

SrcPeH := pointer(Integer(SrcMz)+SrcMz._lfanew);

if (SrcPeH.Signature <> IMAGE_NT_SIGNATURE) then exit;

if (SrcPeH.FileHeader.Characteristics and IMAGE_FILE_DLL <> 0) or

(SrcPeH.FileHeader.Characteristics and IMAGE_FILE_EXECUTABLE_IMAGE = 0)

or (SrcPeH.FileHeader.SizeOfOptionalHeader <> SizeOf(TImageOptionalHeader)) then exit;

SrcPeSecH := Pointer(Integer(SrcPeH)+SizeOf(TImageNtHeaders));

ImageSize := CalcTotalImageSize(SrcMz, Len, SrcPeH, SrcPeSecH);

if ImageSize = 0 then

exit;

Mem := VirtualAlloc(nil, ImageSize, MEM_COMMIT, PAGE_EXECUTE_READWRITE); // 分配内存

if Mem <> nil then

begin

// 计算需

要复制的PE头字节数

l := SrcPeH.OptionalHeader.SizeOfHeaders;

for i := 0 to SrcPeH.FileHeader.NumberOfSections - 1 do

if (SrcPeSecH[i].PointerToRawData <> 0) and (SrcPeSecH[i].PointerToRawData < l) then

l := SrcPeSecH[i].PointerToRawData;

Move(SrcMz^, Mem^, l);

PeH := Pointer(Integer(Mem) + PImageDosHeader(Mem)._lfanew);

PeSecH := Pointer(Integer(PeH) + sizeof(TImageNtHeaders));

Pt := Pointer(Cardinal(Mem) + GetAlignedSize(PeH.OptionalHeader.SizeOfHeaders, PeH.OptionalHeader.SectionAlignment));

for i := 0 to PeH.FileHeader.NumberOfSections - 1 do

begin

// 定位该节在内存中的位置

if PeSecH[i].VirtualAddress <> 0 then

Pt := Pointer(Cardinal(Mem) + PeSecH[i].VirtualAddress);

if PeSecH[i].SizeOfRawData <> 0 then

begin

// 复制数据到内存

Move(Pointer(Cardinal(SrcMz) + PeSecH[i].PointerToRawData)^, pt^, PeSecH[i].SizeOfRawData);

if peSecH[i].Misc.VirtualSize < peSecH[i].SizeOfRawData then

pt := pointer(Cardinal(pt) + GetAlignedSize(PeSecH[i].SizeOfRawData, PeH.OptionalHeader.SectionAlignment))

else

pt := pointer(Cardinal(pt) + GetAlignedSize(peSecH[i].Misc.VirtualSize, peH.OptionalHeader.SectionAlignment));

// pt 定位到下一节开始位置

end

else

pt := pointer(Cardinal(pt) + GetAlignedSize(PeSecH[i].Misc.VirtualSize, PeH.OptionalHeader.SectionAlignment));

end;

result := True;

end;

end;

type

TVirtualAllocEx = function (hProcess: THandle; lpAddress: Pointer;

dwSize, flAllocationType: DWORD; flProtect: DWORD): Pointer; stdcall;

var

MyVirtualAllocEx: TVirtualAllocEx = nil;

function IsNT: Boolean;

begin

result := Assigned(MyVirtualAllocEx);

end;

{ 生成外壳程序命令行 }

function PrepareShellExe(CmdParam: string; BaseAddr, ImageSize: Cardinal): string;

var

r, h, sz: Cardinal;

p: Pointer;

fid, l: Integer;

buf: Pointer;

peH: PImageNtHeaders;

peSecH: PImageSectionHeaders;

begin

if IsNT then

{ NT 系统下直接使用自身程序作为外壳进程 }

result := ParamStr(0) + CmdParam

else begin

// 由于98系统下无法重新分配外壳进程占用内存,所以必须保证运行的外壳程序能容纳目标进程并且加载地址一致

// 此处使用的方法是从资源中释放出一个事先建立好的外壳程序,然后通过修改其PE头使其运行时能加载到指定地址并至少能容纳目标进程

r := FindResource(HInstance, 'SHELL_EXE', RT_RCDATA);

h := LoadResource(HInstance, r);

p := LockResource(h);

l := SizeOfResource(HInstance, r);

GetMem(Buf, l);

Move(p^, Buf^, l); // 读到内存

FreeResource(h);

peH := Pointer(Integer(Buf) + PImageDosHeader(Buf)._lfanew);

peSecH := Pointer(Integer(peH) + sizeof(TImageNtHeaders));

peH.OptionalHeader.ImageBase := BaseAddr; // 修改PE头重的加载基址

if peH.OptionalHeader.SizeOfImage < ImageSize then // 目标比外壳大,修改外壳程序运行时占用的内存

begin

sz := Imagesize - peH.OptionalHeader.SizeOfImage;

Inc(peH.OptionalHeader.SizeOfImage, sz); // 调整总占用内存数

Inc(peSecH[peH.FileHeader.NumberOfSections-1].Misc.VirtualSize, sz); // 调整最后一节占用内存数

end;

// 生成外壳程序文件名, 为本程序改后缀名得到的

// 由于不想 uses SysUtils (一旦 use 了程序将增大80K左右), 而且偷懒，所以只支持最多运行11个进程，后缀名为.dat, .da0~.da9

result := ParamStr(0);

result := copy(result, 1, length(result) - 4) + '.dat';

r := 0;

while r < 10 do

begin

fid := CreateFile(pchar(result), GENERIC_READ or GENERIC_WRITE, 0, nil, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);

if fid < 0 then

begin

result := copy(result, 1, length(result)-3)+'da'+Char(r+Byte('0'));

inc(r);

end

else begin

//SetFilePointer(fid, Imagesize, nil, 0);

//SetEndOfFile(fid);

//SetFilePointer(fid, 0, nil, 0);

WriteFile(fid, Buf^, l, h, nil); // 写入文件

CloseHandle(fid);

break;

end;

end;

result := result + CmdParam; // 生成命令行

FreeMem(Buf);

end;

end;

{ 是否包含可重定向列表 }

function HasRelocationTable(peH: PImageNtHeaders): Boolean;

begin

result := (peH.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress <> 0)

and (peH.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size <> 0);

end;

type

PImageBaseRelocation= ^TImageBaseRelocation;

TImageBaseRelocation = packed record

VirtualAddress: cardinal;

SizeOfBlock: cardinal;

end;

{ 重定向PE用到的地址 }

procedure DoRelocation(peH: PImageNtHeaders; OldBase, NewBase: Pointer);

var

Delta: Cardinal;

p: PImageBaseRelocation;

pw: PWord;

i: Integer;

begin

Delta := Cardinal(NewBase) - peH.OptionalHeader.ImageBase;

p := pointer(cardinal(OldBase) + peH.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress);

while (p.VirtualAddress + p.SizeOfBlock <> 0) do

begin

pw := pointer(Integer(p) + Sizeof(p^));

for i := 1 to (p.SizeOfBlock - Sizeof(p^)) div 2 do

begin

if pw^ and $F000 = $3000 then

Inc(PCardinal(Cardinal(OldBase) + p.VirtualAddress + (pw^ and $0FFF))^, Delta);

inc(pw);

end;

p := Pointer(pw);

end;

end;

type

TZwUnmapViewOfSection = function (Handle, BaseAdr: Cardinal): Cardinal; stdcall;

{ 卸载原外壳占用内存 }

function UnloadShell(ProcHnd, BaseAddr: Cardinal): Boolean;

var

M: HModule;

ZwUnmapViewOfSection: TZwUnmapViewOfSection;

begin

result := False;

m := LoadLibrary('ntdll.dll');

if m <> 0 then

begin

ZwUnmapViewOfSection := GetProcAddress(m, 'ZwUnmapViewOfSection');

if assigned(ZwUnmapViewOfSection) then

result := (ZwUnmapViewOfSection(ProcHnd, BaseAddr) = 0);

FreeLibrary(m);

end;

end;

{ 创建外壳进程并获取其基址、大小和当前运行状态 }

function CreateChild(Cmd: string; var Ctx: TContext; var ProcHnd, ThrdHnd, ProcId, BaseAddr, ImageSize: Cardinal): Boolean;

var

si: TStartUpInfo;

pi: TProcessInformation;

Old: Cardinal;

MemInfo: TMemoryBasicInformation;

p: Pointer;

begin

FillChar(si, Sizeof(si), 0);

FillChar(pi, SizeOf(pi), 0);

si.cb := sizeo

f(si);

result := CreateProcess(nil, PChar(Cmd), nil, nil, False, CREATE_SUSPENDED, nil, nil, si, pi); // 以挂起方式运行进程

if result then

begin

ProcHnd := pi.hProcess;

ThrdHnd := pi.hThread;

ProcId := pi.dwProcessId;

{ 获取外壳进程运行状态，[ctx.Ebx+8]内存处存的是外壳进程的加载基址，ctx.Eax存放有外壳进程的入口地址 }

ctx.ContextFlags := CONTEXT_FULL;

GetThreadContext(ThrdHnd, ctx);

ReadProcessMemory(ProcHnd, Pointer(ctx.Ebx+8), @BaseAddr, SizeOf(Cardinal), Old); // 读取加载基址

p := Pointer(BaseAddr);

{ 计算外壳进程占有的内存 }

while VirtualQueryEx(ProcHnd, p, MemInfo, Sizeof(MemInfo)) <> 0 do

begin

if MemInfo.State = MEM_FREE then

break;

p := Pointer(Cardinal(p) + MemInfo.RegionSize);

end;

ImageSize := Cardinal(p) - Cardinal(BaseAddr);

end;

end;

{ 创建外壳进程并用目标进程替换它然后执行 }

function AttachPE(CmdParam: string; peH: PImageNtHeaders; peSecH: PImageSectionHeaders;

Ptr: Pointer; ImageSize: Cardinal; var ProcId: Cardinal): Cardinal;

var

s: string;

Addr, Size: Cardinal;

ctx: TContext;

Old: Cardinal;

p: Pointer;

Thrd: Cardinal;

begin

result := INVALID_HANDLE_VALUE;

s := PrepareShellExe(CmdParam, peH.OptionalHeader.ImageBase, ImageSize);

if CreateChild(s, ctx, result, Thrd, ProcId, Addr, Size) then

begin

p := nil;

if (peH.OptionalHeader.ImageBase = Addr) and (Size >= ImageSize) then // 外壳进程可以容纳目标进程并且加载地址一致

begin

p := Pointer(Addr);

VirtualProtectEx(result, p, Size, PAGE_EXECUTE_READWRITE, Old);

end

else if IsNT then // 98 下失败

begin

if UnloadShell(result, Addr) then // 卸载外壳进程占有内存

// 重新按目标进程加载基址和大小分配内存

p := MyVirtualAllocEx(Result, Pointer(peH.OptionalHeader.ImageBase), ImageSize, MEM_RESERVE or MEM_COMMIT, PAGE_EXECUTE_READWRITE);

if (p = nil) and hasRelocationTable(peH) then // 分配内存失败并且目标进程支持重定向

begin

// 按任意基址分配内存

p := MyVirtualAllocEx(result, nil, ImageSize, MEM_RESERVE or MEM_COMMIT, PAGE_EXECUTE_READWRITE);

if p <> nil then

DoRelocation(peH, Ptr, p); // 重定向

end;

end;

if p <> nil then

begin

WriteProcessMemory(Result, Pointer(ctx.Ebx+8), @p, Sizeof(DWORD), Old); // 重置目标进程运行环境中的基址

peH.OptionalHeader.ImageBase := Cardinal(p);

if WriteProcessMemory(Result, p, Ptr, ImageSize, Old) then // 复制PE数据到目标进程

begin

ctx.ContextFlags := CONTEXT_FULL;

if Cardinal(p) = Addr then

ctx.Eax := peH.OptionalHeader.ImageBase + peH.OptionalHeader.AddressOfEntryPoint // 重置运行环境中的入口地址

else

ctx.Eax := Cardinal(p) + peH.OptionalHeader.AddressOfEntryPoint;

SetThreadContext(Thrd, ctx); // 更新运行环境

ResumeThread(Thrd); // 执行

CloseHandle(Thrd);

end

else begin // 加载失败,杀掉外壳进程

TerminateProcess(Result, 0);

CloseHandle(Thrd);

CloseHandle(Result);

Result := I

NVALID_HANDLE_VALUE;

end;

end

else begin // 加载失败,杀掉外壳进程

TerminateProcess(Result, 0);

CloseHandle(Thrd);

CloseHandle(Result);

Result := INVALID_HANDLE_VALUE;

end;

end;

end;

function MemExecute(const ABuffer; Len: Integer; CmdParam: string; var ProcessId: Cardinal): Cardinal;

var

peH: PImageNtHeaders;

peSecH: PImageSectionHeaders;

Ptr: Pointer;

peSz: Cardinal;

begin

result := INVALID_HANDLE_VALUE;

if alignPEToMem(ABuffer, Len, peH, peSecH, Ptr, peSz) then

begin

result := AttachPE(CmdParam, peH, peSecH, Ptr, peSz, ProcessId);

VirtualFree(Ptr, peSz, MEM_DECOMMIT);

//VirtualFree(Ptr, 0, MEM_RELEASE);

end;

end;

initialization

MyVirtualAllocEx := GetProcAddress(GetModuleHandle('Kernel32.dll'), 'VirtualAllocEx');

end.下载本文