2 * Emulation of priviledged instructions
4 * Copyright 1995 Alexandre Julliard
7 #include "wine/winuser16.h"
13 #include "sig_context.h"
14 #include "selectors.h"
18 #define IS_V86(context) (EFL_sig(context)&V86_FLAG)
19 #define IS_SEL_32(context,seg) \
20 (IS_V86(context) ? FALSE : IS_SELECTOR_32BIT(seg))
22 #define STACK_sig(context) \
23 (IS_SEL_32(context,SS_sig(context)) ? ESP_sig(context) : SP_sig(context))
25 #define MAKE_PTR(seg,off) \
26 (IS_SELECTOR_SYSTEM(seg) ? (void *)(off) : PTR_SEG_OFF_TO_LIN(seg,off))
28 #define MK_PTR(context,seg,off) \
29 (IS_V86(context) ? DOSMEM_MapRealToLinear(MAKELONG(off,seg)) \
32 #define STACK_PTR(context) \
33 (IS_V86(context) ? DOSMEM_MapRealToLinear(MAKELONG(SP_sig(context),SS_sig(context))) : \
34 (IS_SELECTOR_SYSTEM(SS_sig(context)) ? (void *)ESP_sig(context) : \
35 (PTR_SEG_OFF_TO_LIN(SS_sig(context),STACK_sig(context)))))
37 /* For invalid registers fixup */
38 extern DWORD CallFrom16_Start
,CallFrom16_End
;
41 /***********************************************************************
42 * INSTR_ReplaceSelector
44 * Try to replace an invalid selector by a valid one.
45 * The only selector where it is allowed to do "mov ax,40;mov es,ax"
46 * is the so called 'bimodal' selector 0x40, which points to the BIOS
47 * data segment. Used by (at least) Borland products (and programs compiled
48 * using Borland products).
50 * See Undocumented Windows, Chapter 5, __0040.
52 static BOOL
INSTR_ReplaceSelector( SIGCONTEXT
*context
, WORD
*sel
)
54 if (IS_SELECTOR_SYSTEM(CS_sig(context
)) &&
55 (EIP_sig(context
) >= (DWORD
)&CallFrom16_Start
) &&
56 (EIP_sig(context
) < (DWORD
)&CallFrom16_End
))
58 /* Saved selector may have become invalid when the relay code */
59 /* tries to restore it. We simply clear it. */
65 static WORD sys_timer
= 0;
67 sys_timer
= CreateSystemTimer( 55, DOSMEM_Tick
);
68 *sel
= DOSMEM_BiosDataSeg
;
71 return FALSE
; /* Can't replace selector, crashdump */
75 /***********************************************************************
76 * INSTR_GetOperandAddr
78 * Return the address of an instruction operand (from the mod/rm byte).
80 static BYTE
*INSTR_GetOperandAddr( SIGCONTEXT
*context
, BYTE
*instr
,
81 int long_addr
, int segprefix
, int *len
)
83 int mod
, rm
, base
, index
= 0, ss
= 0, seg
= 0, off
;
85 #define GET_VAL(val,type) \
86 { *val = *(type *)instr; instr += sizeof(type); *len += sizeof(type); }
89 GET_VAL( &mod
, BYTE
);
97 case 0: return (BYTE
*)&EAX_sig(context
);
98 case 1: return (BYTE
*)&ECX_sig(context
);
99 case 2: return (BYTE
*)&EDX_sig(context
);
100 case 3: return (BYTE
*)&EBX_sig(context
);
101 case 4: return (BYTE
*)&ESP_sig(context
);
102 case 5: return (BYTE
*)&EBP_sig(context
);
103 case 6: return (BYTE
*)&ESI_sig(context
);
104 case 7: return (BYTE
*)&EDI_sig(context
);
113 GET_VAL( &sib
, BYTE
);
118 case 0: index
= EAX_sig(context
); break;
119 case 1: index
= ECX_sig(context
); break;
120 case 2: index
= EDX_sig(context
); break;
121 case 3: index
= EBX_sig(context
); break;
122 case 4: index
= 0; break;
123 case 5: index
= EBP_sig(context
); break;
124 case 6: index
= ESI_sig(context
); break;
125 case 7: index
= EDI_sig(context
); break;
131 case 0: base
= EAX_sig(context
); seg
= DS_sig(context
); break;
132 case 1: base
= ECX_sig(context
); seg
= DS_sig(context
); break;
133 case 2: base
= EDX_sig(context
); seg
= DS_sig(context
); break;
134 case 3: base
= EBX_sig(context
); seg
= DS_sig(context
); break;
135 case 4: base
= ESP_sig(context
); seg
= SS_sig(context
); break;
136 case 5: base
= EBP_sig(context
); seg
= SS_sig(context
); break;
137 case 6: base
= ESI_sig(context
); seg
= DS_sig(context
); break;
138 case 7: base
= EDI_sig(context
); seg
= DS_sig(context
); break;
143 if (rm
== 5) /* special case: ds:(disp32) */
145 GET_VAL( &base
, DWORD
);
146 seg
= DS_sig(context
);
150 case 1: /* 8-bit disp */
151 GET_VAL( &off
, BYTE
);
152 base
+= (signed char)off
;
155 case 2: /* 32-bit disp */
156 GET_VAL( &off
, DWORD
);
157 base
+= (signed long)off
;
161 else /* short address */
165 case 0: /* ds:(bx,si) */
166 base
= BX_sig(context
) + SI_sig(context
);
167 seg
= DS_sig(context
);
169 case 1: /* ds:(bx,di) */
170 base
= BX_sig(context
) + DI_sig(context
);
171 seg
= DS_sig(context
);
173 case 2: /* ss:(bp,si) */
174 base
= BP_sig(context
) + SI_sig(context
);
175 seg
= SS_sig(context
);
177 case 3: /* ss:(bp,di) */
178 base
= BP_sig(context
) + DI_sig(context
);
179 seg
= SS_sig(context
);
181 case 4: /* ds:(si) */
182 base
= SI_sig(context
);
183 seg
= DS_sig(context
);
185 case 5: /* ds:(di) */
186 base
= DI_sig(context
);
187 seg
= DS_sig(context
);
189 case 6: /* ss:(bp) */
190 base
= BP_sig(context
);
191 seg
= SS_sig(context
);
193 case 7: /* ds:(bx) */
194 base
= BX_sig(context
);
195 seg
= DS_sig(context
);
202 if (rm
== 6) /* special case: ds:(disp16) */
204 GET_VAL( &base
, WORD
);
205 seg
= DS_sig(context
);
209 case 1: /* 8-bit disp */
210 GET_VAL( &off
, BYTE
);
211 base
+= (signed char)off
;
214 case 2: /* 16-bit disp */
215 GET_VAL( &off
, WORD
);
216 base
+= (signed short)off
;
221 if (segprefix
!= -1) seg
= segprefix
;
223 /* Make sure the segment and offset are valid */
224 if (IS_SELECTOR_SYSTEM(seg
)) return (BYTE
*)(base
+ (index
<< ss
));
225 if (((seg
& 7) != 7) || IS_SELECTOR_FREE(seg
)) return NULL
;
226 if (GET_SEL_LIMIT(seg
) < (base
+ (index
<< ss
))) return NULL
;
227 return (BYTE
*)PTR_SEG_OFF_TO_LIN( seg
, (base
+ (index
<< ss
)) );
232 /***********************************************************************
235 * Emulate the LDS (and LES,LFS,etc.) instruction.
237 static BOOL
INSTR_EmulateLDS( SIGCONTEXT
*context
, BYTE
*instr
, int long_op
,
238 int long_addr
, int segprefix
, int *len
)
241 BYTE
*regmodrm
= instr
+ 1 + (*instr
== 0x0f);
242 BYTE
*addr
= INSTR_GetOperandAddr( context
, regmodrm
,
243 long_addr
, segprefix
, len
);
245 return FALSE
; /* Unable to emulate it */
246 seg
= *(WORD
*)(addr
+ (long_op
? 4 : 2));
248 if (!INSTR_ReplaceSelector( context
, &seg
))
249 return FALSE
; /* Unable to emulate it */
251 /* Now store the offset in the correct register */
253 switch((*regmodrm
>> 3) & 7)
256 if (long_op
) EAX_sig(context
) = *(DWORD
*)addr
;
257 else AX_sig(context
) = *(WORD
*)addr
;
260 if (long_op
) ECX_sig(context
) = *(DWORD
*)addr
;
261 else CX_sig(context
) = *(WORD
*)addr
;
264 if (long_op
) EDX_sig(context
) = *(DWORD
*)addr
;
265 else DX_sig(context
) = *(WORD
*)addr
;
268 if (long_op
) EBX_sig(context
) = *(DWORD
*)addr
;
269 else BX_sig(context
) = *(WORD
*)addr
;
272 if (long_op
) ESP_sig(context
) = *(DWORD
*)addr
;
273 else SP_sig(context
) = *(WORD
*)addr
;
276 if (long_op
) EBP_sig(context
) = *(DWORD
*)addr
;
277 else BP_sig(context
) = *(WORD
*)addr
;
280 if (long_op
) ESI_sig(context
) = *(DWORD
*)addr
;
281 else SI_sig(context
) = *(WORD
*)addr
;
284 if (long_op
) EDI_sig(context
) = *(DWORD
*)addr
;
285 else DI_sig(context
) = *(WORD
*)addr
;
289 /* Store the correct segment in the segment register */
293 case 0xc4: ES_sig(context
) = seg
; break; /* les */
294 case 0xc5: DS_sig(context
) = seg
; break; /* lds */
295 case 0x0f: switch(instr
[1])
297 case 0xb2: SS_sig(context
) = seg
; break; /* lss */
299 case 0xb4: FS_sig(context
) = seg
; break; /* lfs */
302 case 0xb5: GS_sig(context
) = seg
; break; /* lgs */
308 /* Add the opcode size to the total length */
310 *len
+= 1 + (*instr
== 0x0f);
315 /***********************************************************************
316 * INSTR_EmulateInstruction
318 * Emulate a priviledged instruction. Returns TRUE if emulation successful.
320 BOOL
INSTR_EmulateInstruction( SIGCONTEXT
*context
)
322 int prefix
, segprefix
, prefixlen
, len
, repX
, long_op
, long_addr
;
326 long_op
= long_addr
= IS_SEL_32(context
,CS_sig(context
));
327 instr
= (BYTE
*)MK_PTR(context
,CS_sig(context
),EIP_sig(context
));
328 if (!instr
) return FALSE
;
330 /* First handle any possible prefix */
332 segprefix
= -1; /* no prefix */
341 segprefix
= CS_sig(context
);
344 segprefix
= SS_sig(context
);
347 segprefix
= DS_sig(context
);
350 segprefix
= ES_sig(context
);
354 segprefix
= FS_sig(context
);
359 segprefix
= GS_sig(context
);
363 long_op
= !long_op
; /* opcode size prefix */
366 long_addr
= !long_addr
; /* addr size prefix */
368 case 0xf0: /* lock */
370 case 0xf2: /* repne */
373 case 0xf3: /* repe */
377 prefix
= 0; /* no more prefixes */
387 /* Now look at the actual instruction */
391 case 0x07: /* pop es */
392 case 0x17: /* pop ss */
393 case 0x1f: /* pop ds */
395 WORD seg
= *(WORD
*)STACK_PTR( context
);
396 if (INSTR_ReplaceSelector( context
, &seg
))
400 case 0x07: ES_sig(context
) = seg
; break;
401 case 0x17: SS_sig(context
) = seg
; break;
402 case 0x1f: DS_sig(context
) = seg
; break;
404 STACK_sig(context
) += long_op
? 4 : 2;
405 EIP_sig(context
) += prefixlen
+ 1;
409 break; /* Unable to emulate it */
411 case 0x0f: /* extended instruction */
414 case 0x22: /* mov eax, crX */
417 fprintf(stderr
,"mov eax,cr0 at 0x%08lx, EAX=0x%08lx\n",
418 EIP_sig(context
),EAX_sig(context
)
420 EIP_sig(context
) += prefixlen
+3;
423 break; /*fallthrough to bad instruction handling */
425 break; /*fallthrough to bad instruction handling */
426 case 0x20: /* mov crX, eax */
428 case 0xe0: /* mov cr4, eax */
429 /* CR4 register . See linux/arch/i386/mm/init.c, X86_CR4_ defs
430 * bit 0: VME Virtual Mode Exception ?
431 * bit 1: PVI Protected mode Virtual Interrupt
432 * bit 2: TSD Timestamp disable
433 * bit 3: DE Debugging extensions
434 * bit 4: PSE Page size extensions
435 * bit 5: PAE Physical address extension
436 * bit 6: MCE Machine check enable
437 * bit 7: PGE Enable global pages
438 * bit 8: PCE Enable performance counters at IPL3
440 fprintf(stderr
,"mov cr4,eax at 0x%08lx\n",EIP_sig(context
));
441 EAX_sig(context
) = 0;
442 EIP_sig(context
) += prefixlen
+3;
444 case 0xc0: /* mov cr0, eax */
445 fprintf(stderr
,"mov cr0,eax at 0x%08lx\n",EIP_sig(context
));
446 EAX_sig(context
) = 0x10; /* FIXME: set more bits ? */
447 EIP_sig(context
) += prefixlen
+3;
449 default: /* fallthrough to illegal instruction */
452 /* fallthrough to illegal instruction */
455 case 0xa1: /* pop fs */
457 WORD seg
= *(WORD
*)STACK_PTR( context
);
458 if (INSTR_ReplaceSelector( context
, &seg
))
460 FS_sig(context
) = seg
;
461 STACK_sig(context
) += long_op
? 4 : 2;
462 EIP_sig(context
) += prefixlen
+ 2;
470 case 0xa9: /* pop gs */
472 WORD seg
= *(WORD
*)STACK_PTR( context
);
473 if (INSTR_ReplaceSelector( context
, &seg
))
475 GS_sig(context
) = seg
;
476 STACK_sig(context
) += long_op
? 4 : 2;
477 EIP_sig(context
) += prefixlen
+ 2;
484 case 0xb2: /* lss addr,reg */
486 case 0xb4: /* lfs addr,reg */
489 case 0xb5: /* lgs addr,reg */
491 if (INSTR_EmulateLDS( context
, instr
, long_op
,
492 long_addr
, segprefix
, &len
))
494 EIP_sig(context
) += prefixlen
+ len
;
499 break; /* Unable to emulate it */
501 case 0x6c: /* insb */
502 case 0x6d: /* insw/d */
503 case 0x6e: /* outsb */
504 case 0x6f: /* outsw/d */
506 int typ
= *instr
; /* Just in case it's overwritten. */
507 int outp
= (typ
>= 0x6e);
508 unsigned long count
= repX
?
509 (long_addr
? ECX_sig(context
) : CX_sig(context
)) : 1;
510 int opsize
= (typ
& 1) ? (long_op
? 4 : 2) : 1;
511 int step
= (EFL_sig(context
) & 0x400) ? -opsize
: +opsize
;
512 int seg
= outp
? DS_sig(context
) : ES_sig(context
); /* FIXME: is this right? */
515 /* FIXME: Check segment readable. */
518 /* FIXME: Check segment writeable. */
524 ECX_sig(context
) = 0;
534 data
= MK_PTR(context
, seg
,
535 long_addr
? ESI_sig(context
) : SI_sig(context
));
536 if (long_addr
) ESI_sig(context
) += step
;
537 else SI_sig(context
) += step
;
541 data
= MK_PTR(context
, seg
,
542 long_addr
? EDI_sig(context
) : DI_sig(context
));
543 if (long_addr
) EDI_sig(context
) += step
;
544 else DI_sig(context
) += step
;
550 *((BYTE
*)data
) = IO_inport( DX_sig(context
), 1);
551 TRACE(io
, "0x%x < %02x @ %04x:%04x\n", DX_sig(context
),
552 *((BYTE
*)data
), CS_sig(context
), IP_sig(context
));
557 *((DWORD
*)data
) = IO_inport( DX_sig(context
), 4);
558 TRACE(io
, "0x%x < %08lx @ %04x:%04x\n", DX_sig(context
),
559 *((DWORD
*)data
), CS_sig(context
), IP_sig(context
));
563 *((WORD
*)data
) = IO_inport( DX_sig(context
), 2);
564 TRACE(io
, "0x%x < %04x @ %04x:%04x\n", DX_sig(context
),
565 *((WORD
*)data
), CS_sig(context
), IP_sig(context
));
569 IO_outport( DX_sig(context
), 1, *((BYTE
*)data
));
570 TRACE(io
, "0x%x > %02x @ %04x:%04x\n", DX_sig(context
),
571 *((BYTE
*)data
), CS_sig(context
), IP_sig(context
));
576 IO_outport( DX_sig(context
), 4, *((DWORD
*)data
));
577 TRACE(io
, "0x%x > %08lx @ %04x:%04x\n", DX_sig(context
),
578 *((DWORD
*)data
), CS_sig(context
), IP_sig(context
));
582 IO_outport( DX_sig(context
), 2, *((WORD
*)data
));
583 TRACE(io
, "0x%x > %04x @ %04x:%04x\n", DX_sig(context
),
584 *((WORD
*)data
), CS_sig(context
), IP_sig(context
));
589 EIP_sig(context
) += prefixlen
+ 1;
593 case 0x8e: /* mov XX,segment_reg */
596 BYTE
*addr
= INSTR_GetOperandAddr(context
, instr
+ 1,
597 long_addr
, segprefix
, &len
);
599 break; /* Unable to emulate it */
601 if (!INSTR_ReplaceSelector( context
, &seg
))
602 break; /* Unable to emulate it */
604 switch((instr
[1] >> 3) & 7)
607 ES_sig(context
) = seg
;
608 EIP_sig(context
) += prefixlen
+ len
+ 1;
613 SS_sig(context
) = seg
;
614 EIP_sig(context
) += prefixlen
+ len
+ 1;
617 DS_sig(context
) = seg
;
618 EIP_sig(context
) += prefixlen
+ len
+ 1;
622 FS_sig(context
) = seg
;
623 EIP_sig(context
) += prefixlen
+ len
+ 1;
628 GS_sig(context
) = seg
;
629 EIP_sig(context
) += prefixlen
+ len
+ 1;
637 break; /* Unable to emulate it */
639 case 0xc4: /* les addr,reg */
640 case 0xc5: /* lds addr,reg */
641 if (INSTR_EmulateLDS( context
, instr
, long_op
,
642 long_addr
, segprefix
, &len
))
644 EIP_sig(context
) += prefixlen
+ len
;
647 break; /* Unable to emulate it */
649 case 0xcd: /* int <XX> */
652 ERR(int, "int xx from 32-bit code is not supported.\n");
653 break; /* Unable to emulate it */
657 FARPROC16 addr
= INT_GetPMHandler( instr
[1] );
658 WORD
*stack
= (WORD
*)STACK_PTR( context
);
659 /* Push the flags and return address on the stack */
660 *(--stack
) = FL_sig(context
);
661 *(--stack
) = CS_sig(context
);
662 *(--stack
) = IP_sig(context
) + prefixlen
+ 2;
663 STACK_sig(context
) -= 3 * sizeof(WORD
);
664 /* Jump to the interrupt handler */
665 CS_sig(context
) = HIWORD(addr
);
666 EIP_sig(context
) = LOWORD(addr
);
670 case 0xcf: /* iret */
673 DWORD
*stack
= (DWORD
*)STACK_PTR( context
);
674 EIP_sig(context
) = *stack
++;
675 CS_sig(context
) = *stack
++;
676 EFL_sig(context
) = *stack
;
677 STACK_sig(context
) += 3*sizeof(DWORD
); /* Pop the return address and flags */
681 WORD
*stack
= (WORD
*)STACK_PTR( context
);
682 EIP_sig(context
) = *stack
++;
683 CS_sig(context
) = *stack
++;
684 FL_sig(context
) = *stack
;
685 STACK_sig(context
) += 3*sizeof(WORD
); /* Pop the return address and flags */
689 case 0xe4: /* inb al,XX */
690 AL_sig(context
) = IO_inport( instr
[1], 1 );
691 TRACE(io
, "0x%x < %02x @ %04x:%04x\n", instr
[1],
692 AL_sig(context
), CS_sig(context
), IP_sig(context
));
693 EIP_sig(context
) += prefixlen
+ 2;
696 case 0xe5: /* in (e)ax,XX */
699 EAX_sig(context
) = IO_inport( instr
[1], 4 );
700 TRACE(io
, "0x%x < %08lx @ %04x:%04x\n", instr
[1],
701 EAX_sig(context
), CS_sig(context
), IP_sig(context
));
705 AX_sig(context
) = IO_inport( instr
[1], 2 );
706 TRACE(io
, "0x%x < %04x @ %04x:%04x\n", instr
[1],
707 AX_sig(context
), CS_sig(context
), IP_sig(context
));
709 EIP_sig(context
) += prefixlen
+ 2;
712 case 0xe6: /* outb XX,al */
713 IO_outport( instr
[1], 1, AL_sig(context
) );
714 TRACE(io
, "0x%x > %02x @ %04x:%04x\n", instr
[1],
715 AL_sig(context
), CS_sig(context
), IP_sig(context
));
716 EIP_sig(context
) += prefixlen
+ 2;
719 case 0xe7: /* out XX,(e)ax */
722 IO_outport( instr
[1], 4, EAX_sig(context
) );
723 TRACE(io
, "0x%x > %08lx @ %04x:%04x\n", instr
[1],
724 EAX_sig(context
), CS_sig(context
), IP_sig(context
));
728 IO_outport( instr
[1], 2, AX_sig(context
) );
729 TRACE(io
, "0x%x > %04x @ %04x:%04x\n", instr
[1],
730 AX_sig(context
), CS_sig(context
), IP_sig(context
));
732 EIP_sig(context
) += prefixlen
+ 2;
735 case 0xec: /* inb al,dx */
736 AL_sig(context
) = IO_inport( DX_sig(context
), 1 );
737 TRACE(io
, "0x%x < %02x @ %04x:%04x\n", DX_sig(context
),
738 AL_sig(context
), CS_sig(context
), IP_sig(context
));
739 EIP_sig(context
) += prefixlen
+ 1;
742 case 0xed: /* in (e)ax,dx */
745 EAX_sig(context
) = IO_inport( DX_sig(context
), 4 );
746 TRACE(io
, "0x%x < %08lx @ %04x:%04x\n", DX_sig(context
),
747 EAX_sig(context
), CS_sig(context
), IP_sig(context
));
751 AX_sig(context
) = IO_inport( DX_sig(context
), 2 );
752 TRACE(io
, "0x%x < %04x @ %04x:%04x\n", DX_sig(context
),
753 AX_sig(context
), CS_sig(context
), IP_sig(context
));
755 EIP_sig(context
) += prefixlen
+ 1;
758 case 0xee: /* outb dx,al */
759 IO_outport( DX_sig(context
), 1, AL_sig(context
) );
760 TRACE(io
, "0x%x > %02x @ %04x:%04x\n", DX_sig(context
),
761 AL_sig(context
), CS_sig(context
), IP_sig(context
));
762 EIP_sig(context
) += prefixlen
+ 1;
765 case 0xef: /* out dx,(e)ax */
768 IO_outport( DX_sig(context
), 4, EAX_sig(context
) );
769 TRACE(io
, "0x%x > %08lx @ %04x:%04x\n", DX_sig(context
),
770 EAX_sig(context
), CS_sig(context
), IP_sig(context
));
774 IO_outport( DX_sig(context
), 2, AX_sig(context
) );
775 TRACE(io
, "0x%x > %04x @ %04x:%04x\n", DX_sig(context
),
776 AX_sig(context
), CS_sig(context
), IP_sig(context
));
778 EIP_sig(context
) += prefixlen
+ 1;
781 case 0xfa: /* cli, ignored */
782 EIP_sig(context
) += prefixlen
+ 1;
785 case 0xfb: /* sti, ignored */
786 EIP_sig(context
) += prefixlen
+ 1;
791 /* Check for Win16 __GP handler */
792 gpHandler
= HasGPHandler16( PTR_SEG_OFF_TO_SEGPTR( CS_sig(context
),
793 EIP_sig(context
) ) );
796 WORD
*stack
= (WORD
*)STACK_PTR( context
);
797 *--stack
= CS_sig(context
);
798 *--stack
= EIP_sig(context
);
799 STACK_sig(context
) -= 2*sizeof(WORD
);
801 CS_sig(context
) = SELECTOROF( gpHandler
);
802 EIP_sig(context
) = OFFSETOF( gpHandler
);
806 MSG("Unexpected Windows program segfault"
807 " - opcode = %x\n", *instr
);
808 return FALSE
; /* Unable to emulate it */