2 * KERNEL32 thunks and other undocumented stuff
4 * Copyright 1997-1998 Marcus Meissner
5 * Copyright 1998 Ulrich Weigand
16 #include "stackframe.h"
18 #include "selectors.h"
23 #include "flatthunk.h"
27 /***********************************************************************
29 * Win95 internal thunks *
31 ***********************************************************************/
33 /***********************************************************************
34 * Generates a FT_Prolog call.
36 * 0FB6D1 movzbl edx,cl
37 * 8B1495xxxxxxxx mov edx,[4*edx + targetTable]
38 * 68xxxxxxxx push FT_Prolog
41 static void _write_ftprolog(LPBYTE relayCode
,DWORD
*targetTable
) {
45 *x
++ = 0x0f;*x
++=0xb6;*x
++=0xd1; /* movzbl edx,cl */
46 *x
++ = 0x8B;*x
++=0x14;*x
++=0x95;*(DWORD
**)x
= targetTable
;
47 x
+=4; /* mov edx, [4*edx + targetTable] */
48 *x
++ = 0x68; *(DWORD
*)x
= (DWORD
)GetProcAddress32(GetModuleHandle32A("KERNEL32"),"FT_Prolog");
49 x
+=4; /* push FT_Prolog */
50 *x
++ = 0xC3; /* lret */
51 /* fill rest with 0xCC / int 3 */
54 /***********************************************************************
55 * _write_qtthunk (internal)
56 * Generates a QT_Thunk style call.
59 * 8A4DFC mov cl , [ebp-04]
60 * 8B148Dxxxxxxxx mov edx, [4*ecx + targetTable]
61 * B8yyyyyyyy mov eax, QT_Thunk
64 static void _write_qtthunk(
65 LPBYTE relayCode
, /* [in] start of QT_Thunk stub */
66 DWORD
*targetTable
/* [in] start of thunk (for index lookup) */
71 *x
++ = 0x33;*x
++=0xC9; /* xor ecx,ecx */
72 *x
++ = 0x8A;*x
++=0x4D;*x
++=0xFC; /* movb cl,[ebp-04] */
73 *x
++ = 0x8B;*x
++=0x14;*x
++=0x8D;*(DWORD
**)x
= targetTable
;
74 x
+=4; /* mov edx, [4*ecx + targetTable */
75 *x
++ = 0xB8; *(DWORD
*)x
= (DWORD
)GetProcAddress32(GetModuleHandle32A("KERNEL32"),"QT_Thunk");
76 x
+=4; /* mov eax , QT_Thunk */
77 *x
++ = 0xFF; *x
++ = 0xE0; /* jmp eax */
78 /* should fill the rest of the 32 bytes with 0xCC */
81 /***********************************************************************
84 static LPVOID
_loadthunk(LPCSTR module
, LPCSTR func
, LPCSTR module32
,
85 struct ThunkDataCommon
*TD32
, DWORD checksum
)
87 struct ThunkDataCommon
*TD16
;
91 if ((hmod
= LoadLibrary16(module
)) <= 32)
93 ERR(thunk
, "(%s, %s, %s): Unable to load '%s', error %d\n",
94 module
, func
, module32
, module
, hmod
);
98 if ( !(ordinal
= NE_GetOrdinal(hmod
, func
))
99 || !(TD16
= PTR_SEG_TO_LIN(NE_GetEntryPointEx(hmod
, ordinal
, FALSE
))))
101 ERR(thunk
, "(%s, %s, %s): Unable to find '%s'\n",
102 module
, func
, module32
, func
);
106 if (TD32
&& memcmp(TD16
->magic
, TD32
->magic
, 4))
108 ERR(thunk
, "(%s, %s, %s): Bad magic %c%c%c%c (should be %c%c%c%c)\n",
109 module
, func
, module32
,
110 TD16
->magic
[0], TD16
->magic
[1], TD16
->magic
[2], TD16
->magic
[3],
111 TD32
->magic
[0], TD32
->magic
[1], TD32
->magic
[2], TD32
->magic
[3]);
115 if (TD32
&& TD16
->checksum
!= TD32
->checksum
)
117 ERR(thunk
, "(%s, %s, %s): Wrong checksum %08lx (should be %08lx)\n",
118 module
, func
, module32
, TD16
->checksum
, TD32
->checksum
);
122 if (!TD32
&& checksum
&& checksum
!= *(LPDWORD
)TD16
)
124 ERR(thunk
, "(%s, %s, %s): Wrong checksum %08lx (should be %08lx)\n",
125 module
, func
, module32
, *(LPDWORD
)TD16
, checksum
);
132 /***********************************************************************
133 * GetThunkStuff (KERNEL32.53)
135 LPVOID WINAPI
GetThunkStuff(LPSTR module
, LPSTR func
)
137 return _loadthunk(module
, func
, "<kernel>", NULL
, 0L);
140 /***********************************************************************
141 * GetThunkBuff (KERNEL32.52)
142 * Returns a pointer to ThkBuf in the 16bit library SYSTHUNK.DLL.
144 LPVOID WINAPI
GetThunkBuff(void)
146 return GetThunkStuff("SYSTHUNK.DLL", "ThkBuf");
149 /***********************************************************************
150 * ThunkConnect32 (KERNEL32)
151 * Connects a 32bit and a 16bit thunkbuffer.
153 UINT32 WINAPI
ThunkConnect32(
154 struct ThunkDataCommon
*TD
, /* [in/out] thunkbuffer */
155 LPSTR thunkfun16
, /* [in] win16 thunkfunction */
156 LPSTR module16
, /* [in] name of win16 dll */
157 LPSTR module32
, /* [in] name of win32 dll */
158 HMODULE32 hmod32
, /* [in] hmodule of win32 dll */
159 DWORD dwReason
/* [in] initialisation argument */
163 if (!lstrncmp32A(TD
->magic
, "SL01", 4))
167 TRACE(thunk
, "SL01 thunk %s (%lx) <- %s (%s), Reason: %ld\n",
168 module32
, (DWORD
)TD
, module16
, thunkfun16
, dwReason
);
170 else if (!lstrncmp32A(TD
->magic
, "LS01", 4))
174 TRACE(thunk
, "LS01 thunk %s (%lx) -> %s (%s), Reason: %ld\n",
175 module32
, (DWORD
)TD
, module16
, thunkfun16
, dwReason
);
179 ERR(thunk
, "Invalid magic %c%c%c%c\n",
180 TD
->magic
[0], TD
->magic
[1], TD
->magic
[2], TD
->magic
[3]);
186 case DLL_PROCESS_ATTACH
:
188 struct ThunkDataCommon
*TD16
;
189 if (!(TD16
= _loadthunk(module16
, thunkfun16
, module32
, TD
, 0L)))
194 struct ThunkDataSL32
*SL32
= (struct ThunkDataSL32
*)TD
;
195 struct ThunkDataSL16
*SL16
= (struct ThunkDataSL16
*)TD16
;
196 struct SLTargetDB
*tdb
;
198 if (SL16
->fpData
== NULL
)
200 ERR(thunk
, "ThunkConnect16 was not called!\n");
204 SL32
->data
= SL16
->fpData
;
206 tdb
= HeapAlloc(GetProcessHeap(), 0, sizeof(*tdb
));
207 tdb
->process
= PROCESS_Current();
208 tdb
->targetTable
= (DWORD
*)(thunkfun16
+ SL32
->offsetTargetTable
);
210 tdb
->next
= SL32
->data
->targetDB
; /* FIXME: not thread-safe! */
211 SL32
->data
->targetDB
= tdb
;
213 TRACE(thunk
, "Process %08lx allocated TargetDB entry for ThunkDataSL %08lx\n",
214 (DWORD
)PROCESS_Current(), (DWORD
)SL32
->data
);
218 struct ThunkDataLS32
*LS32
= (struct ThunkDataLS32
*)TD
;
219 struct ThunkDataLS16
*LS16
= (struct ThunkDataLS16
*)TD16
;
221 LS32
->targetTable
= PTR_SEG_TO_LIN(LS16
->targetTable
);
223 /* write QT_Thunk and FT_Prolog stubs */
224 _write_qtthunk ((LPBYTE
)TD
+ LS32
->offsetQTThunk
, LS32
->targetTable
);
225 _write_ftprolog((LPBYTE
)TD
+ LS32
->offsetFTProlog
, LS32
->targetTable
);
230 case DLL_PROCESS_DETACH
:
238 /**********************************************************************
239 * QT_Thunk (KERNEL32)
241 * The target address is in EDX.
242 * The 16 bit arguments start at ESP+4.
243 * The number of 16bit argumentbytes is EBP-ESP-0x44 (68 Byte thunksetup).
246 REGS_ENTRYPOINT(QT_Thunk
)
250 THDB
*thdb
= THREAD_Current();
252 memcpy(&context16
,context
,sizeof(context16
));
254 CS_reg(&context16
) = HIWORD(EDX_reg(context
));
255 IP_reg(&context16
) = LOWORD(EDX_reg(context
));
256 EBP_reg(&context16
) = OFFSETOF( thdb
->cur_stack
)
257 + (WORD
)&((STACK16FRAME
*)0)->bp
;
259 argsize
= EBP_reg(context
)-ESP_reg(context
)-0x44;
261 memcpy( ((LPBYTE
)THREAD_STACK16(thdb
))-argsize
,
262 (LPBYTE
)ESP_reg(context
)+4, argsize
);
264 EAX_reg(context
) = Callbacks
->CallRegisterShortProc( &context16
, argsize
);
265 EDX_reg(context
) = HIWORD(EAX_reg(context
));
269 /**********************************************************************
270 * FT_Prolog (KERNEL32.233)
272 * The set of FT_... thunk routines is used instead of QT_Thunk,
273 * if structures have to be converted from 32-bit to 16-bit
274 * (change of member alignment, conversion of members).
276 * The thunk function (as created by the thunk compiler) calls
277 * FT_Prolog at the beginning, to set up a stack frame and
278 * allocate a 64 byte buffer on the stack.
279 * The input parameters (target address and some flags) are
280 * saved for later use by FT_Thunk.
282 * Input: EDX 16-bit target address (SEGPTR)
283 * CX bits 0..7 target number (in target table)
284 * bits 8..9 some flags (unclear???)
285 * bits 10..15 number of DWORD arguments
287 * Output: A new stackframe is created, and a 64 byte buffer
288 * allocated on the stack. The layout of the stack
289 * on return is as follows:
291 * (ebp+4) return address to caller of thunk function
293 * (ebp-4) saved EBX register of caller
294 * (ebp-8) saved ESI register of caller
295 * (ebp-12) saved EDI register of caller
296 * (ebp-16) saved ECX register, containing flags
297 * (ebp-20) bitmap containing parameters that are to be converted
298 * by FT_Thunk; it is initialized to 0 by FT_Prolog and
299 * filled in by the thunk code before calling FT_Thunk
303 * (ebp-48) saved EAX register of caller (unclear, never restored???)
304 * (ebp-52) saved EDX register, containing 16-bit thunk target
309 * ESP is EBP-68 on return.
313 REGS_ENTRYPOINT(FT_Prolog
)
315 /* Pop return address to thunk code */
316 EIP_reg(context
) = STACK32_POP(context
);
318 /* Build stack frame */
319 STACK32_PUSH(context
, EBP_reg(context
));
320 EBP_reg(context
) = ESP_reg(context
);
322 /* Allocate 64-byte Thunk Buffer */
323 ESP_reg(context
) -= 64;
324 memset((char *)ESP_reg(context
), '\0', 64);
326 /* Store Flags (ECX) and Target Address (EDX) */
327 /* Save other registers to be restored later */
328 *(DWORD
*)(EBP_reg(context
) - 4) = EBX_reg(context
);
329 *(DWORD
*)(EBP_reg(context
) - 8) = ESI_reg(context
);
330 *(DWORD
*)(EBP_reg(context
) - 12) = EDI_reg(context
);
331 *(DWORD
*)(EBP_reg(context
) - 16) = ECX_reg(context
);
333 *(DWORD
*)(EBP_reg(context
) - 48) = EAX_reg(context
);
334 *(DWORD
*)(EBP_reg(context
) - 52) = EDX_reg(context
);
336 /* Push return address back onto stack */
337 STACK32_PUSH(context
, EIP_reg(context
));
340 /**********************************************************************
341 * FT_Thunk (KERNEL32.234)
343 * This routine performs the actual call to 16-bit code,
344 * similar to QT_Thunk. The differences are:
345 * - The call target is taken from the buffer created by FT_Prolog
346 * - Those arguments requested by the thunk code (by setting the
347 * corresponding bit in the bitmap at EBP-20) are converted
348 * from 32-bit pointers to segmented pointers (those pointers
349 * are guaranteed to point to structures copied to the stack
350 * by the thunk code, so we always use the 16-bit stack selector
351 * for those addresses).
353 * The bit #i of EBP-20 corresponds here to the DWORD starting at
356 * FIXME: It is unclear what happens if there are more than 32 WORDs
357 * of arguments, so that the single DWORD bitmap is no longer
361 REGS_ENTRYPOINT(FT_Thunk
)
363 DWORD mapESPrelative
= *(DWORD
*)(EBP_reg(context
) - 20);
364 DWORD callTarget
= *(DWORD
*)(EBP_reg(context
) - 52);
368 LPBYTE newstack
, oldstack
;
369 THDB
*thdb
= THREAD_Current();
371 memcpy(&context16
,context
,sizeof(context16
));
373 CS_reg(&context16
) = HIWORD(callTarget
);
374 IP_reg(&context16
) = LOWORD(callTarget
);
375 EBP_reg(&context16
) = OFFSETOF( thdb
->cur_stack
)
376 + (WORD
)&((STACK16FRAME
*)0)->bp
;
378 argsize
= EBP_reg(context
)-ESP_reg(context
)-0x44;
379 newstack
= ((LPBYTE
)THREAD_STACK16(thdb
))-argsize
;
380 oldstack
= (LPBYTE
)ESP_reg(context
)+4;
382 memcpy( newstack
, oldstack
, argsize
);
384 for (i
= 0; i
< 32; i
++) /* NOTE: What about > 32 arguments? */
385 if (mapESPrelative
& (1 << i
))
387 SEGPTR
*arg
= (SEGPTR
*)(newstack
+ 2*i
);
388 *arg
= PTR_SEG_OFF_TO_SEGPTR(SELECTOROF(thdb
->cur_stack
),
389 OFFSETOF(thdb
->cur_stack
) - argsize
390 + (*(LPBYTE
*)arg
- oldstack
));
393 EAX_reg(context
) = Callbacks
->CallRegisterShortProc( &context16
, argsize
);
394 EDX_reg(context
) = HIWORD(EAX_reg(context
));
397 /**********************************************************************
398 * FT_ExitNN (KERNEL32.218 - 232)
400 * One of the FT_ExitNN functions is called at the end of the thunk code.
401 * It removes the stack frame created by FT_Prolog, moves the function
402 * return from EBX to EAX (yes, FT_Thunk did use EAX for the return
403 * value, but the thunk code has moved it from EAX to EBX in the
404 * meantime ... :-), restores the caller's EBX, ESI, and EDI registers,
405 * and perform a return to the CALLER of the thunk code (while removing
406 * the given number of arguments from the caller's stack).
409 static void FT_Exit(CONTEXT
*context
, int nPopArgs
)
411 /* Return value is in EBX */
412 EAX_reg(context
) = EBX_reg(context
);
414 /* Restore EBX, ESI, and EDI registers */
415 EBX_reg(context
) = *(DWORD
*)(EBP_reg(context
) - 4);
416 ESI_reg(context
) = *(DWORD
*)(EBP_reg(context
) - 8);
417 EDI_reg(context
) = *(DWORD
*)(EBP_reg(context
) - 12);
419 /* Clean up stack frame */
420 ESP_reg(context
) = EBP_reg(context
);
421 EBP_reg(context
) = STACK32_POP(context
);
423 /* Pop return address to CALLER of thunk code */
424 EIP_reg(context
) = STACK32_POP(context
);
425 /* Remove arguments */
426 ESP_reg(context
) += nPopArgs
;
427 /* Push return address back onto stack */
428 STACK32_PUSH(context
, EIP_reg(context
));
431 REGS_ENTRYPOINT(FT_Exit0
) { FT_Exit(context
, 0); }
432 REGS_ENTRYPOINT(FT_Exit4
) { FT_Exit(context
, 4); }
433 REGS_ENTRYPOINT(FT_Exit8
) { FT_Exit(context
, 8); }
434 REGS_ENTRYPOINT(FT_Exit12
) { FT_Exit(context
, 12); }
435 REGS_ENTRYPOINT(FT_Exit16
) { FT_Exit(context
, 16); }
436 REGS_ENTRYPOINT(FT_Exit20
) { FT_Exit(context
, 20); }
437 REGS_ENTRYPOINT(FT_Exit24
) { FT_Exit(context
, 24); }
438 REGS_ENTRYPOINT(FT_Exit28
) { FT_Exit(context
, 28); }
439 REGS_ENTRYPOINT(FT_Exit32
) { FT_Exit(context
, 32); }
440 REGS_ENTRYPOINT(FT_Exit36
) { FT_Exit(context
, 36); }
441 REGS_ENTRYPOINT(FT_Exit40
) { FT_Exit(context
, 40); }
442 REGS_ENTRYPOINT(FT_Exit44
) { FT_Exit(context
, 44); }
443 REGS_ENTRYPOINT(FT_Exit48
) { FT_Exit(context
, 48); }
444 REGS_ENTRYPOINT(FT_Exit52
) { FT_Exit(context
, 52); }
445 REGS_ENTRYPOINT(FT_Exit56
) { FT_Exit(context
, 56); }
448 /**********************************************************************
449 * WOWCallback16 (KERNEL32.62)(WOW32.2)
450 * Calls a win16 function with a single DWORD argument.
454 DWORD WINAPI
WOWCallback16(
455 FARPROC16 fproc
, /* [in] win16 function to call */
456 DWORD arg
/* [in] single DWORD argument to function */
459 TRACE(thunk
,"(%p,0x%08lx)...\n",fproc
,arg
);
460 ret
= Callbacks
->CallWOWCallbackProc(fproc
,arg
);
461 TRACE(thunk
,"... returns %ld\n",ret
);
465 /**********************************************************************
466 * WOWCallback16Ex (KERNEL32.55)(WOW32.3)
467 * Calls a function in 16bit code.
471 BOOL32 WINAPI
WOWCallback16Ex(
472 FARPROC16 vpfn16
, /* [in] win16 function to call */
473 DWORD dwFlags
, /* [in] flags */
474 DWORD cbArgs
, /* [in] nr of arguments */
475 LPVOID pArgs
, /* [in] pointer to arguments (LPDWORD) */
476 LPDWORD pdwRetCode
/* [out] return value of win16 function */
478 return Callbacks
->CallWOWCallback16Ex(vpfn16
,dwFlags
,cbArgs
,pArgs
,pdwRetCode
);
481 /***********************************************************************
482 * ThunkInitLS (KERNEL32.43)
483 * A thunkbuffer link routine
484 * The thunkbuf looks like:
486 * 00: DWORD length ? don't know exactly
487 * 04: SEGPTR ptr ? where does it point to?
488 * The pointer ptr is written into the first DWORD of 'thunk'.
489 * (probably correct implemented)
492 * segmented pointer to thunk?
494 DWORD WINAPI
ThunkInitLS(
495 LPDWORD thunk
, /* [in] win32 thunk */
496 LPCSTR thkbuf
, /* [in] thkbuffer name in win16 dll */
497 DWORD len
, /* [in] thkbuffer length */
498 LPCSTR dll16
, /* [in] name of win16 dll */
499 LPCSTR dll32
/* [in] name of win32 dll (FIXME: not used?) */
503 if (!(addr
= _loadthunk( dll16
, thkbuf
, dll32
, NULL
, len
)))
508 *(DWORD
*)thunk
= addr
[1];
513 /***********************************************************************
514 * Common32ThkLS (KERNEL32.45)
516 * This is another 32->16 thunk, independent of the QT_Thunk/FT_Thunk
517 * style thunks. The basic difference is that the parameter conversion
518 * is done completely on the *16-bit* side here. Thus we do not call
519 * the 16-bit target directly, but call a common entry point instead.
520 * This entry function then calls the target according to the target
521 * number passed in the DI register.
523 * Input: EAX SEGPTR to the common 16-bit entry point
524 * CX offset in thunk table (target number * 4)
525 * DX error return value if execution fails (unclear???)
526 * EDX.HI number of DWORD parameters
528 * (Note that we need to move the thunk table offset from CX to DI !)
530 * The called 16-bit stub expects its stack to look like this:
532 * (esp+40) 32-bit arguments
534 * (esp+8) 32 byte of stack space available as buffer
535 * (esp) 8 byte return address for use with 0x66 lret
537 * The called 16-bit stub uses a 0x66 lret to return to 32-bit code,
538 * and uses the EAX register to return a DWORD return value.
539 * Thus we need to use a special assembly glue routine
540 * (CallRegisterLongProc instead of CallRegisterShortProc).
542 * Finally, we return to the caller, popping the arguments off
545 * FIXME: The called function uses EBX to return the number of
546 * arguments that are to be popped off the caller's stack.
547 * This is clobbered by the assembly glue, so we simply use
548 * the original EDX.HI to get the number of arguments.
549 * (Those two values should be equal anyway ...?)
552 REGS_ENTRYPOINT(Common32ThkLS
)
556 THDB
*thdb
= THREAD_Current();
558 memcpy(&context16
,context
,sizeof(context16
));
560 DI_reg(&context16
) = CX_reg(context
);
561 CS_reg(&context16
) = HIWORD(EAX_reg(context
));
562 IP_reg(&context16
) = LOWORD(EAX_reg(context
));
563 EBP_reg(&context16
) = OFFSETOF( thdb
->cur_stack
)
564 + (WORD
)&((STACK16FRAME
*)0)->bp
;
566 argsize
= HIWORD(EDX_reg(context
)) * 4;
568 memcpy( ((LPBYTE
)THREAD_STACK16(thdb
))-argsize
,
569 (LPBYTE
)ESP_reg(context
)+4, argsize
);
571 EAX_reg(context
) = Callbacks
->CallRegisterLongProc(&context16
, argsize
+ 32);
573 /* Clean up caller's stack frame */
575 EIP_reg(context
) = STACK32_POP(context
);
576 ESP_reg(context
) += argsize
;
577 STACK32_PUSH(context
, EIP_reg(context
));
580 /***********************************************************************
581 * OT_32ThkLSF (KERNEL32.40)
583 * YET Another 32->16 thunk. The difference to Common32ThkLS is that
584 * argument processing is done on both the 32-bit and the 16-bit side:
585 * The 32-bit side prepares arguments, copying them onto the stack.
587 * When this routine is called, the first word on the stack is the
588 * number of argument bytes prepared by the 32-bit code, and EDX
589 * contains the 16-bit target address.
591 * The called 16-bit routine is another relaycode, doing further
592 * argument processing and then calling the real 16-bit target
593 * whose address is stored at [bp-04].
595 * The call proceeds using a normal CallRegisterShortProc.
596 * After return from the 16-bit relaycode, the arguments need
597 * to be copied *back* to the 32-bit stack, since the 32-bit
598 * relaycode processes output parameters.
600 * Note that we copy twice the number of arguments, since some of the
601 * 16-bit relaycodes in SYSTHUNK.DLL directly access the original
602 * arguments of the caller!
604 * (Note that this function seems only to be used for
605 * OLECLI32 -> OLECLI and OLESVR32 -> OLESVR thunking.)
607 REGS_ENTRYPOINT(OT_32ThkLSF
)
611 THDB
*thdb
= THREAD_Current();
613 memcpy(&context16
,context
,sizeof(context16
));
615 CS_reg(&context16
) = HIWORD(EDX_reg(context
));
616 IP_reg(&context16
) = LOWORD(EDX_reg(context
));
617 EBP_reg(&context16
) = OFFSETOF( thdb
->cur_stack
)
618 + (WORD
)&((STACK16FRAME
*)0)->bp
;
620 argsize
= 2 * *(WORD
*)(ESP_reg(context
) + 4) + 2;
622 memcpy( ((LPBYTE
)THREAD_STACK16(thdb
))-argsize
,
623 (LPBYTE
)ESP_reg(context
)+4, argsize
);
625 EAX_reg(context
) = Callbacks
->CallRegisterShortProc(&context16
, argsize
);
627 memcpy( (LPBYTE
)ESP_reg(context
)+4,
628 ((LPBYTE
)THREAD_STACK16(thdb
))-argsize
, argsize
);
631 /***********************************************************************
632 * ThunkInitLSF (KERNEL32.41)
633 * A thunk setup routine.
634 * Expects a pointer to a preinitialized thunkbuffer in the first argument
636 * 00..03: unknown (pointer, check _41, _43, _46)
639 * 06..23: unknown (space for replacement code, check .90)
641 * 24:>E800000000 call offset 29
642 * 29:>58 pop eax ( target of call )
643 * 2A: 2D25000000 sub eax,0x00000025 ( now points to offset 4 )
644 * 2F: BAxxxxxxxx mov edx,xxxxxxxx
645 * 34: 68yyyyyyyy push KERNEL32.90
649 * 3E ... 59: unknown (space for replacement code?)
650 * 5A: E8xxxxxxxx call <32bitoffset xxxxxxxx>
652 * 60: 81EA25xxxxxx sub edx, 0x25xxxxxx
654 * 67: 68xxxxxxxx push xxxxxxxx
655 * 6C: 68yyyyyyyy push KERNEL32.89
658 * This function checks if the code is there, and replaces the yyyyyyyy entries
659 * by the functionpointers.
660 * The thunkbuf looks like:
662 * 00: DWORD length ? don't know exactly
663 * 04: SEGPTR ptr ? where does it point to?
664 * The segpointer ptr is written into the first DWORD of 'thunk'.
667 * unclear, pointer to win16 thkbuffer?
669 LPVOID WINAPI
ThunkInitLSF(
670 LPBYTE thunk
, /* [in] win32 thunk */
671 LPCSTR thkbuf
, /* [in] thkbuffer name in win16 dll */
672 DWORD len
, /* [in] length of thkbuffer */
673 LPCSTR dll16
, /* [in] name of win16 dll */
674 LPCSTR dll32
/* [in] name of win32 dll */
676 HMODULE32 hkrnl32
= GetModuleHandle32A("KERNEL32");
679 /* FIXME: add checks for valid code ... */
680 /* write pointers to kernel32.89 and kernel32.90 (+ordinal base of 1) */
681 *(DWORD
*)(thunk
+0x35) = (DWORD
)GetProcAddress32(hkrnl32
,(LPSTR
)90);
682 *(DWORD
*)(thunk
+0x6D) = (DWORD
)GetProcAddress32(hkrnl32
,(LPSTR
)89);
685 if (!(addr
= _loadthunk( dll16
, thkbuf
, dll32
, NULL
, len
)))
688 addr2
= PTR_SEG_TO_LIN(addr
[1]);
690 *(DWORD
*)thunk
= (DWORD
)addr2
;
695 /***********************************************************************
696 * FT_PrologPrime (KERNEL32.89)
698 * This function is called from the relay code installed by
699 * ThunkInitLSF. It replaces the location from where it was
700 * called by a standard FT_Prolog call stub (which is 'primed'
701 * by inserting the correct target table pointer).
702 * Finally, it calls that stub.
704 * Input: ECX target number + flags (passed through to FT_Prolog)
705 * (ESP) offset of location where target table pointer
706 * is stored, relative to the start of the relay code
707 * (ESP+4) pointer to start of relay code
708 * (this is where the FT_Prolog call stub gets written to)
710 * Note: The two DWORD arguments get popped from the stack.
713 REGS_ENTRYPOINT(FT_PrologPrime
)
715 DWORD targetTableOffset
= STACK32_POP(context
);
716 LPBYTE relayCode
= (LPBYTE
)STACK32_POP(context
);
717 DWORD
*targetTable
= *(DWORD
**)(relayCode
+targetTableOffset
);
718 DWORD targetNr
= LOBYTE(ECX_reg(context
));
720 _write_ftprolog(relayCode
, targetTable
);
722 /* We should actually call the relay code now, */
723 /* but we skip it and go directly to FT_Prolog */
724 EDX_reg(context
) = targetTable
[targetNr
];
725 __regs_FT_Prolog(context
);
728 /***********************************************************************
729 * QT_ThunkPrime (KERNEL32.90)
731 * This function corresponds to FT_PrologPrime, but installs a
732 * call stub for QT_Thunk instead.
734 * Input: (EBP-4) target number (passed through to QT_Thunk)
735 * EDX target table pointer location offset
736 * EAX start of relay code
739 REGS_ENTRYPOINT(QT_ThunkPrime
)
741 DWORD targetTableOffset
= EDX_reg(context
);
742 LPBYTE relayCode
= (LPBYTE
)EAX_reg(context
);
743 DWORD
*targetTable
= *(DWORD
**)(relayCode
+targetTableOffset
);
744 DWORD targetNr
= LOBYTE(*(DWORD
*)(EBP_reg(context
) - 4));
746 _write_qtthunk(relayCode
, targetTable
);
748 /* We should actually call the relay code now, */
749 /* but we skip it and go directly to QT_Thunk */
750 EDX_reg(context
) = targetTable
[targetNr
];
751 __regs_QT_Thunk(context
);
754 /***********************************************************************
756 * Another thunkbuf link routine.
757 * The start of the thunkbuf looks like this:
759 * 04: SEGPTR address for thunkbuffer pointer
762 VOID WINAPI
ThunkInitSL(
763 LPBYTE thunk
, /* [in] start of thunkbuffer */
764 LPCSTR thkbuf
, /* [in] name/ordinal of thunkbuffer in win16 dll */
765 DWORD len
, /* [in] length of thunkbuffer */
766 LPCSTR dll16
, /* [in] name of win16 dll containing the thkbuf */
767 LPCSTR dll32
/* [in] win32 dll. FIXME: strange, unused */
771 if (!(addr
= _loadthunk( dll16
, thkbuf
, dll32
, NULL
, len
)))
774 *(DWORD
*)PTR_SEG_TO_LIN(addr
[1]) = (DWORD
)thunk
;
777 /**********************************************************************
782 BOOL32 WINAPI
SSInit()
787 /**********************************************************************
788 * SSOnBigStack KERNEL32.87
789 * Check if thunking is initialized (ss selector set up etc.)
790 * We do that differently, so just return TRUE.
795 BOOL32 WINAPI
SSOnBigStack()
797 TRACE(thunk
, "Yes, thunking is initialized\n");
801 /**********************************************************************
803 * One of the real thunking functions. This one seems to be for 32<->32
804 * thunks. It should probably be capable of crossing processboundaries.
806 * And YES, I've seen nr=48 (somewhere in the Win95 32<->16 OLE coupling)
809 DWORD WINAPIV
SSCall(
810 DWORD nr
, /* [in] number of argument bytes */
811 DWORD flags
, /* [in] FIXME: flags ? */
812 FARPROC32 fun
, /* [in] function to call */
813 ... /* [in/out] arguments */
816 DWORD
*args
= ((DWORD
*)&fun
) + 1;
819 dbg_decl_str(thunk
, 256);
821 dsprintf(thunk
,"0x%08lx,",args
[i
]);
822 TRACE(thunk
,"(%ld,0x%08lx,%p,[%s])\n",
823 nr
,flags
,fun
,dbg_str(thunk
));
828 case 4: ret
= fun(args
[0]);
830 case 8: ret
= fun(args
[0],args
[1]);
832 case 12: ret
= fun(args
[0],args
[1],args
[2]);
834 case 16: ret
= fun(args
[0],args
[1],args
[2],args
[3]);
836 case 20: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4]);
838 case 24: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4],args
[5]);
840 case 28: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4],args
[5],args
[6]);
842 case 32: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4],args
[5],args
[6],args
[7]);
844 case 36: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4],args
[5],args
[6],args
[7],args
[8]);
846 case 40: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4],args
[5],args
[6],args
[7],args
[8],args
[9]);
848 case 44: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4],args
[5],args
[6],args
[7],args
[8],args
[9],args
[10]);
850 case 48: ret
= fun(args
[0],args
[1],args
[2],args
[3],args
[4],args
[5],args
[6],args
[7],args
[8],args
[9],args
[10],args
[11]);
853 WARN(thunk
,"Unsupported nr of arguments, %ld\n",nr
);
858 TRACE(thunk
," returning %ld ...\n",ret
);
862 /**********************************************************************
863 * W32S_BackTo32 (KERNEL32.51)
865 REGS_ENTRYPOINT(W32S_BackTo32
)
867 LPDWORD stack
= (LPDWORD
)ESP_reg( context
);
868 FARPROC32 proc
= (FARPROC32
) stack
[0];
870 EAX_reg( context
) = proc( stack
[2], stack
[3], stack
[4], stack
[5], stack
[6],
871 stack
[7], stack
[8], stack
[9], stack
[10], stack
[11] );
873 EIP_reg( context
) = stack
[1];
876 /**********************************************************************
877 * AllocSLCallback (KERNEL32)
879 * Win95 uses some structchains for callbacks. It allocates them
880 * in blocks of 100 entries, size 32 bytes each, layout:
882 * 0: PTR nextblockstart
884 * 8: WORD sel ( start points to blockstart)
888 * 18: PDB *owning_process;
891 * We ignore this for now. (Just a note for further developers)
892 * FIXME: use this method, so we don't waste selectors...
894 * Following code is then generated by AllocSLCallback. The code is 16 bit, so
895 * the 0x66 prefix switches from word->long registers.
898 * 6668x arg2 x pushl <arg2>
900 * EAx arg1 x jmpf <arg1>
902 * returns the startaddress of this thunk.
904 * Note, that they look very similair to the ones allocates by THUNK_Alloc.
906 * segmented pointer to the start of the thunk
910 DWORD finalizer
, /* [in] finalizer function */
911 DWORD callback
/* [in] callback function */
913 LPBYTE x
,thunk
= HeapAlloc( GetProcessHeap(), 0, 32 );
917 *x
++=0x66;*x
++=0x5a; /* popl edx */
918 *x
++=0x66;*x
++=0x68;*(DWORD
*)x
=finalizer
;x
+=4; /* pushl finalizer */
919 *x
++=0x66;*x
++=0x52; /* pushl edx */
920 *x
++=0xea;*(DWORD
*)x
=callback
;x
+=4; /* jmpf callback */
922 *(PDB32
**)(thunk
+18) = PROCESS_Current();
924 sel
= SELECTOR_AllocBlock( thunk
, 32, SEGMENT_CODE
, FALSE
, FALSE
);
928 /**********************************************************************
929 * FreeSLCallback (KERNEL32.274)
930 * Frees the specified 16->32 callback
934 DWORD x
/* [in] 16 bit callback (segmented pointer?) */
936 FIXME(win32
,"(0x%08lx): stub\n",x
);
940 /**********************************************************************
941 * GetTEBSelectorFS (KERNEL.475)
942 * Set the 16-bit %fs to the 32-bit %fs (current TEB selector)
944 VOID WINAPI
GetTEBSelectorFS( CONTEXT
*context
)
946 GET_FS( FS_reg(context
) );
949 /**********************************************************************
950 * KERNEL_431 (KERNEL.431)
951 * IsPeFormat (W32SYS.2)
952 * Checks the passed filename if it is a PE format executeable
957 BOOL16 WINAPI
IsPeFormat(
958 LPSTR fn
, /* [in] filename to executeable */
959 HFILE16 hf16
/* [in] open file, if filename is NULL */
961 IMAGE_DOS_HEADER mzh
;
962 HFILE32 hf
=HFILE16_TO_HFILE32(hf16
);
967 hf
= OpenFile32(fn
,&ofs
,OF_READ
);
968 if (hf
==HFILE_ERROR32
)
971 _llseek32(hf
,0,SEEK_SET
);
972 if (sizeof(mzh
)!=_lread32(hf
,&mzh
,sizeof(mzh
))) {
976 if (mzh
.e_magic
!=IMAGE_DOS_SIGNATURE
) {
977 WARN(dosmem
,"File has not got dos signature!\n");
981 _llseek32(hf
,mzh
.e_lfanew
,SEEK_SET
);
982 if (sizeof(DWORD
)!=_lread32(hf
,&xmagic
,sizeof(DWORD
))) {
987 return (xmagic
== IMAGE_NT_SIGNATURE
);
990 /***********************************************************************
991 * WOWHandle32 (KERNEL32.57)(WOW32.16)
992 * Converts a win16 handle of type into the respective win32 handle.
993 * We currently just return this handle, since most handles are the same
994 * for win16 and win32.
998 HANDLE32 WINAPI
WOWHandle32(
999 WORD handle
, /* [in] win16 handle */
1000 WOW_HANDLE_TYPE type
/* [in] handle type */
1002 TRACE(win32
,"(0x%04x,%d)\n",handle
,type
);
1003 return (HANDLE32
)handle
;
1006 /***********************************************************************
1007 * K32Thk1632Prolog (KERNEL32.492)
1009 REGS_ENTRYPOINT(K32Thk1632Prolog
)
1011 LPBYTE code
= (LPBYTE
)EIP_reg(context
) - 5;
1013 /* Arrrgh! SYSTHUNK.DLL just has to re-implement another method
1014 of 16->32 thunks instead of using one of the standard methods!
1015 This means that SYSTHUNK.DLL itself switches to a 32-bit stack,
1016 and does a far call to the 32-bit code segment of OLECLI32/OLESVR32.
1017 Unfortunately, our CallTo/CallFrom mechanism is therefore completely
1018 bypassed, which means it will crash the next time the 32-bit OLE
1019 code thunks down again to 16-bit (this *will* happen!).
1021 The following hack tries to recognize this situation.
1022 This is possible since the called stubs in OLECLI32/OLESVR32 all
1023 look exactly the same:
1024 00 E8xxxxxxxx call K32Thk1632Prolog
1025 05 FF55FC call [ebp-04]
1026 08 E8xxxxxxxx call K32Thk1632Epilog
1029 If we recognize this situation, we try to simulate the actions
1030 of our CallTo/CallFrom mechanism by copying the 16-bit stack
1031 to our 32-bit stack, creating a proper STACK16FRAME and
1032 updating thdb->cur_stack. */
1034 if ( code
[5] == 0xFF && code
[6] == 0x55 && code
[7] == 0xFC
1035 && code
[13] == 0x66 && code
[14] == 0xCB)
1037 WORD stackSel
= NtCurrentTeb()->stack_sel
;
1038 DWORD stackBase
= GetSelectorBase(stackSel
);
1040 THDB
*thdb
= THREAD_Current();
1041 DWORD argSize
= EBP_reg(context
) - ESP_reg(context
);
1042 char *stack16
= (char *)ESP_reg(context
);
1043 char *stack32
= (char *)thdb
->cur_stack
- argSize
;
1044 STACK16FRAME
*frame16
= (STACK16FRAME
*)stack16
- 1;
1046 TRACE(thunk
, "before SYSTHUNK hack: EBP: %08lx ESP: %08lx cur_stack: %08lx\n",
1047 EBP_reg(context
), ESP_reg(context
), thdb
->cur_stack
);
1049 memset(frame16
, '\0', sizeof(STACK16FRAME
));
1050 frame16
->frame32
= (STACK32FRAME
*)thdb
->cur_stack
;
1051 frame16
->ebp
= EBP_reg(context
);
1053 memcpy(stack32
, stack16
, argSize
);
1054 thdb
->cur_stack
= PTR_SEG_OFF_TO_SEGPTR(stackSel
, (DWORD
)frame16
- stackBase
);
1056 ESP_reg(context
) = (DWORD
)stack32
;
1057 EBP_reg(context
) = ESP_reg(context
) + argSize
;
1059 TRACE(thunk
, "after SYSTHUNK hack: EBP: %08lx ESP: %08lx cur_stack: %08lx\n",
1060 EBP_reg(context
), ESP_reg(context
), thdb
->cur_stack
);
1063 SYSLEVEL_ReleaseWin16Lock();
1066 /***********************************************************************
1067 * K32Thk1632Epilog (KERNEL32.491)
1069 REGS_ENTRYPOINT(K32Thk1632Epilog
)
1071 LPBYTE code
= (LPBYTE
)EIP_reg(context
) - 13;
1073 SYSLEVEL_RestoreWin16Lock();
1075 /* We undo the SYSTHUNK hack if necessary. See K32Thk1632Prolog. */
1077 if ( code
[5] == 0xFF && code
[6] == 0x55 && code
[7] == 0xFC
1078 && code
[13] == 0x66 && code
[14] == 0xCB)
1080 THDB
*thdb
= THREAD_Current();
1081 STACK16FRAME
*frame16
= (STACK16FRAME
*)PTR_SEG_TO_LIN(thdb
->cur_stack
);
1082 char *stack16
= (char *)(frame16
+ 1);
1083 DWORD argSize
= frame16
->ebp
- (DWORD
)stack16
;
1084 char *stack32
= (char *)frame16
->frame32
- argSize
;
1086 DWORD nArgsPopped
= ESP_reg(context
) - (DWORD
)stack32
;
1088 TRACE(thunk
, "before SYSTHUNK hack: EBP: %08lx ESP: %08lx cur_stack: %08lx\n",
1089 EBP_reg(context
), ESP_reg(context
), thdb
->cur_stack
);
1091 thdb
->cur_stack
= (DWORD
)frame16
->frame32
;
1093 ESP_reg(context
) = (DWORD
)stack16
+ nArgsPopped
;
1094 EBP_reg(context
) = frame16
->ebp
;
1096 TRACE(thunk
, "after SYSTHUNK hack: EBP: %08lx ESP: %08lx cur_stack: %08lx\n",
1097 EBP_reg(context
), ESP_reg(context
), thdb
->cur_stack
);