unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TForm1 = class(TForm) Button1: TButton; Memo1: TMemo; Button2: TButton; Button3: TButton; procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); procedure Button3Click(Sender: TObject); procedure FormDestroy(Sender: TObject); procedure FormCreate(Sender: TObject); private { Private declarations } procedure ShowMsg(s: string); public { Public declarations } end; var Form1: TForm1; implementation {$R *.dfm} uses MLDE32Unit; const DesPath = C:\Program Files\Borland\Delphi6\Projects\Adv APIHOOK\Test\vt.exe; Func2Hook = FreeLibrary; var //must be a globle variable PtrReal: Pointer; cbStolen: Cardinal; NtDllBase, NtDllLength: integer; p: pointer; h:dword; procedure TForm1.ShowMsg(s: string); begin Memo1.Lines.Add(s); end; procedure TForm1.Button1Click(Sender: TObject); label FakeCode, RtnCode; var // si: STARTUPINFO; // pi: PROCESS_INFORMATION; OriginalBytes: Array [0..4] of Char; HookJmp: PChar; Rtn: Cardinal; Bytes: Array [0..4] of Char; tmp: Cardinal; peb, ldr, flink: pointer; bs: DWORD; begin PtrReal := nil; NtDllLength := 0; NtDllBase := GetModuleHandle(ntdll.dll); asm mov eax,fs:[$30] mov peb,eax end; ldr := pointer(dword(pointer(dword(peb)+12)^)); flink := pointer(dword(pointer(dword(ldr)+12)^)); p := flink; repeat bs := DWORD(pointer(dword(p)+$18)^); if bs = NtDllBase then begin NtDllLength := DWORD(pointer(dword(p)+$20)^); break; end; p := pointer(dword(p^)); until dword(flink) = dword(p^); if NtDllLength = 0 then ShowMsg(Cant get ntdll.dll image size!); { ShowMsg(Creating suspended process ...); ZeroMemory(@si, sizeof(STARTUPINFO)); si.cb := sizeof(STARTUPINFO); CreateProcess(DesPath, nil, nil, nil, False, CREATE_SUSPENDED, nil, nil, si, pi); } ShowMsg(Preparing HOOK + Func2Hook + ...); PtrReal := GetProcAddress(GetModuleHandle(Kernel32.dll), Func2Hook); if Assigned(PtrReal) then ShowMsg(Real + Func2Hook + Addr: + inttohex(DWORD(PtrReal), 8)) else begin ShowMsg( Addr: + Func2Hook + is unreadable! Exit!); // ResumeThread(pi.hThread); Exit; end; ReadProcessMemory(GetCurrentProcess, PtrReal, @Bytes, 5, Rtn); // ReadProcessMemory(pi.hProcess, PtrReal, @Bytes, 5, Rtn); if Bytes[0] <> Chr($E9) then begin CopyMemory(@OriginalBytes, @Bytes, 5); ShowMsg(Func2Hook + havnt been hooked!); end else begin ShowMsg(Func2Hook + have been hooked! Exit!); // ResumeThread(pi.hThread); exit; end; cbStolen :=0; while cbStolen < 5 do cbStolen := cbStolen + LDE32(Pointer(DWORD(PtrReal) + cbStolen)); ShowMsg(Lets steal the first + inttostr(cbStolen) + bytes :)); ShowMsg(But make it writable first ...); if VirtualProtect(PtrReal ,cbStolen , PAGE_EXECUTE_READWRITE, @tmp) then ShowMsg(Make + inttohex(DWORD(PtrReal), 8) + writable succeed!) else begin ShowMsg(Hoops! Make + inttohex(DWORD(PtrReal), 8) + writable failed! Exit!!); // ResumeThread(pi.hThread); exit; end; ShowMsg(Assemble Jmp codes & hook + Func2Hook + ...); GetMem(HookJmp, 5); try HookJmp[0] := Chr($E9); asm push eax lea eax, FakeCode mov tmp, eax pop eax end; tmp := tmp - DWORD(PtrReal) - 5; CopyMemory(@HookJmp[1], @tmp, 4); asm push eax lea eax, RtnCode mov tmp, eax pop eax end; VirtualProtect(Pointer(tmp) ,cbStolen , PAGE_EXECUTE_READWRITE, @Rtn); CopyMemory(Pointer(tmp), PtrReal, cbStolen); WriteProcessMemory(GetCurrentProcess, PtrReal, HookJmp, 5, Rtn); // WriteProcessMemory(pi.hProcess, PtrReal, HookJmp, 5, Rtn); ShowMsg(Hook + Func2Hook + succeed! Resume thread!); finally Freemem(HookJmp); // ResumeThread(pi.hThread); end; exit; FakeCode: //No strings from here on asm int 3 end; asm push eax lea eax, [esp+4] mov p, eax pop eax end; if dword(p^) - ntdllbase < NtDllLength then asm pop p pop eax pop eax pop eax mov eax, 0 jmp p // push p // ret end; //messagebox(0,pchar(p),,0); RtnCode: asm nop nop nop nop nop nop nop nop nop nop nop nop nop mov eax, PtrReal add eax, cbStolen jmp eax end; end; var Ptr, ppp: Pointer; procedure TForm1.Button2Click(Sender: TObject); begin {asm call ppp; end; exit; } Button3Click(nil); Ptr := VirtualAlloc(nil, 1024, MEM_COMMIT, PAGE_EXECUTE_READWRITE); if not Assigned(Ptr) then Memo1.Lines.Add(Fatal Error: VirtualAlloc failed!) else Memo1.Lines.Add(VirtualAlloc succeed! Ptr = + inttohex(DWORD(Ptr), 8)); end; procedure TForm1.FormDestroy(Sender: TObject); begin Button3Click(nil); UnmapViewOfFile(ppp); CloseHandle(h); end; procedure TForm1.Button3Click(Sender: TObject); begin if Assigned(Ptr) then VirtualFree(Ptr, 0, MEM_RELEASE); end; procedure TForm1.FormCreate(Sender: TObject); begin h := CreateFileMapping($FFFFFFFF, nil, PAGE_READWRITE or SEC_COMMIT, 0, 1, pe); ppp := MapViewOfFile(h,FILE_MAP_ALL_ACCESS,0,0,0); caption := inttohex(dword(ppp),8); char(ppp^) := Chr($C3); end; end. ====== Unit1里有很多垃圾代码,因为这个防hook的程序只是一个副产品。有用代码写成dll注入其他进程就可以防hook了,已经试过没问题。代码风格比较差,不过不知道怎么改的更好(如将FakeCode部分放到单独过程中)。如果你改好了希望能发给我一份。 MLDE32Unit代码来自29A第七期,作者忘记了,不好意思。




