if1632/snoop.c

   1 /*
   2  * 386-specific Win16 dll<->dll snooping functions
   3  *
   4  * Copyright 1998 Marcus Meissner
   5  */
   6
   7 #include <assert.h>
   8 #include <string.h>
   9 #include <stdio.h>
  10 #include "winbase.h"
  11 #include "windef.h"
  12 #include "winnt.h"
  13 #include "heap.h"
  14 #include "global.h"
  15 #include "selectors.h"
  16 #include "stackframe.h"
  17 #include "builtin16.h"
  18 #include "snoop.h"
  19 #include "debugtools.h"
  20
  21 DEFAULT_DEBUG_CHANNEL(snoop);
  22
  23 #ifdef __i386__
  24
  25 #include "pshpack1.h"
  26
  27 void WINAPI SNOOP16_Entry(FARPROC proc, LPBYTE args, CONTEXT86 *context);
  28 void WINAPI SNOOP16_Return(FARPROC proc, LPBYTE args, CONTEXT86 *context);
  29
  30 typedef struct tagSNOOP16_FUN {
  31         /* code part */
  32         BYTE            lcall;          /* 0x9a call absolute with segment */
  33         DWORD           snr;
  34         /* unreached */
  35         int             nrofargs;
  36         FARPROC16       origfun;
  37         char            *name;
  38 } SNOOP16_FUN;
  39
  40 typedef struct tagSNOOP16_DLL {
  41         HMODULE16       hmod;
  42         HANDLE16        funhandle;
  43         SNOOP16_FUN     *funs;
  44         LPCSTR          name;
  45         struct tagSNOOP16_DLL   *next;
  46 } SNOOP16_DLL;
  47
  48 typedef struct tagSNOOP16_RETURNENTRY {
  49         /* code part */
  50         BYTE            lcall;          /* 0x9a call absolute with segment */
  51         DWORD           snr;
  52         /* unreached */
  53         FARPROC16       origreturn;
  54         SNOOP16_DLL     *dll;
  55         DWORD           ordinal;
  56         WORD            origSP;
  57         WORD            *args;          /* saved args across a stdcall */
  58 } SNOOP16_RETURNENTRY;
  59
  60 typedef struct tagSNOOP16_RETURNENTRIES {
  61         SNOOP16_RETURNENTRY entry[65500/sizeof(SNOOP16_RETURNENTRY)];
  62         HANDLE16        rethandle;
  63         struct tagSNOOP16_RETURNENTRIES *next;
  64 } SNOOP16_RETURNENTRIES;
  65
  66 typedef struct tagSNOOP16_RELAY {
  67         WORD            pushbp;         /* 0x5566 */
  68         BYTE            pusheax;        /* 0x50 */
  69         WORD            pushax;         /* 0x5066 */
  70         BYTE            pushl;          /* 0x68 */
  71         DWORD           realfun;        /* SNOOP16_Return */
  72         BYTE            lcall;          /* 0x9a call absolute with segment */
  73         DWORD           callfromregs;
  74         WORD            seg;
  75         WORD            lret;           /* 0xcb66 */
  76 } SNOOP16_RELAY;
  77
  78 #include "poppack.h"
  79
  80 static  SNOOP16_DLL             *firstdll = NULL;
  81 static  SNOOP16_RETURNENTRIES   *firstrets = NULL;
  82 static  SNOOP16_RELAY           *snr;
  83 static  HANDLE16                xsnr = 0;
  84
  85 void
  86 SNOOP16_RegisterDLL(NE_MODULE *pModule,LPCSTR name) {
  87         SNOOP16_DLL     **dll = &(firstdll);
  88         char            *s;
  89
  90         if (!TRACE_ON(snoop)) return;
  91         if (!snr) {
  92                 xsnr=GLOBAL_Alloc(GMEM_ZEROINIT,2*sizeof(*snr),0,TRUE,TRUE,FALSE);
  93                 snr = GlobalLock16(xsnr);
  94                 snr[0].pushbp   = 0x5566;
  95                 snr[0].pusheax  = 0x50;
  96                 snr[0].pushax   = 0x5066;
  97                 snr[0].pushl    = 0x68;
  98                 snr[0].realfun  = (DWORD)SNOOP16_Entry;
  99                 snr[0].lcall    = 0x9a;
 100                 snr[0].callfromregs = (DWORD)CallFrom16Register;
 101                 snr[0].seg      = __get_cs();
 102                 snr[0].lret     = 0xcb66;
 103
 104                 snr[1].pushbp   = 0x5566;
 105                 snr[1].pusheax  = 0x50;
 106                 snr[1].pushax   = 0x5066;
 107                 snr[1].pushl    = 0x68;
 108                 snr[1].realfun  = (DWORD)SNOOP16_Return;
 109                 snr[1].lcall    = 0x9a;
 110                 snr[1].callfromregs = (DWORD)CallFrom16Register;
 111                 snr[1].seg      = __get_cs();
 112                 snr[1].lret     = 0xcb66;
 113         }
 114         while (*dll) {
 115                 if ((*dll)->hmod == pModule->self)
 116                         return; /* already registered */
 117                 dll = &((*dll)->next);
 118         }
 119         *dll = (SNOOP16_DLL*)HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,sizeof(SNOOP16_DLL));
 120         (*dll)->next    = NULL;
 121         (*dll)->hmod    = pModule->self;
 122         if ((s=strrchr(name,'\\')))
 123                 name = s+1;
 124         (*dll)->name    = HEAP_strdupA(GetProcessHeap(),0,name);
 125         if ((s=strrchr((*dll)->name,'.')))
 126                 *s='\0';
 127         (*dll)->funhandle = GlobalHandleToSel16(GLOBAL_Alloc(GMEM_ZEROINIT,65535,0,TRUE,FALSE,FALSE));
 128         (*dll)->funs = GlobalLock16((*dll)->funhandle);
 129         if (!(*dll)->funs) {
 130                 HeapFree(GetProcessHeap(),0,*dll);
 131                 FIXME("out of memory\n");
 132                 return;
 133         }
 134         memset((*dll)->funs,0,65535);
 135 }
 136
 137 FARPROC16
 138 SNOOP16_GetProcAddress16(HMODULE16 hmod,DWORD ordinal,FARPROC16 origfun) {
 139         SNOOP16_DLL                     *dll = firstdll;
 140         SNOOP16_FUN                     *fun;
 141         NE_MODULE                       *pModule = NE_GetPtr(hmod);
 142         unsigned char                   *cpnt;
 143         char                            name[200];
 144
 145         if (!TRACE_ON(snoop) || !pModule || !HIWORD(origfun))
 146                 return origfun;
 147         if (!*(LPBYTE)PTR_SEG_TO_LIN(origfun)) /* 0x00 is an imposs. opcode, poss. dataref. */
 148                 return origfun;
 149         while (dll) {
 150                 if (hmod == dll->hmod)
 151                         break;
 152                 dll=dll->next;
 153         }
 154         if (!dll)       /* probably internal */
 155                 return origfun;
 156         if (ordinal>65535/sizeof(SNOOP16_FUN))
 157                 return origfun;
 158         fun = dll->funs+ordinal;
 159         /* already done? */
 160         fun->lcall      = 0x9a;
 161         fun->snr        = MAKELONG(0,xsnr);
 162         fun->origfun    = origfun;
 163         if (fun->name)
 164                 return (FARPROC16)(SEGPTR)MAKELONG(((char*)fun-(char*)dll->funs),dll->funhandle);
 165         cpnt = (unsigned char *)pModule + pModule->name_table;
 166         while (*cpnt) {
 167                 cpnt += *cpnt + 1 + sizeof(WORD);
 168                 if (*(WORD*)(cpnt+*cpnt+1) == ordinal) {
 169                         sprintf(name,"%.*s",*cpnt,cpnt+1);
 170                         break;
 171                 }
 172         }
 173         /* Now search the non-resident names table */
 174
 175         if (!*cpnt && pModule->nrname_handle) {
 176                 cpnt = (char *)GlobalLock16( pModule->nrname_handle );
 177                 while (*cpnt) {
 178                         cpnt += *cpnt + 1 + sizeof(WORD);
 179                         if (*(WORD*)(cpnt+*cpnt+1) == ordinal) {
 180                                     sprintf(name,"%.*s",*cpnt,cpnt+1);
 181                                     break;
 182                         }
 183                 }
 184         }
 185         if (*cpnt)
 186                 fun->name = HEAP_strdupA(GetProcessHeap(),0,name);
 187         else
 188                 fun->name = HEAP_strdupA(GetProcessHeap(),0,"");
 189         if (!SNOOP_ShowDebugmsgSnoop(dll->name, ordinal, fun->name))
 190                 return origfun;
 191
 192         /* more magic. do not try to snoop thunk data entries (MMSYSTEM) */
 193         if (strchr(fun->name,'_')) {
 194                 char *s=strchr(fun->name,'_');
 195
 196                 if (!strncasecmp(s,"_thunkdata",10)) {
 197                         HeapFree(GetProcessHeap(),0,fun->name);
 198                         fun->name = NULL;
 199                         return origfun;
 200                 }
 201         }
 202         fun->lcall      = 0x9a;
 203         fun->snr        = MAKELONG(0,xsnr);
 204         fun->origfun    = origfun;
 205         fun->nrofargs   = -1;
 206         return (FARPROC16)(SEGPTR)MAKELONG(((char*)fun-(char*)dll->funs),dll->funhandle);
 207 }
 208
 209 #define CALLER1REF (*(DWORD*)(PTR_SEG_OFF_TO_LIN(SS_reg(context),LOWORD(ESP_reg(context))+4)))
 210 void WINAPI SNOOP16_Entry(FARPROC proc, LPBYTE args, CONTEXT86 *context) {
 211         DWORD           ordinal=0;
 212         DWORD           entry=(DWORD)PTR_SEG_OFF_TO_LIN(CS_reg(context),LOWORD(EIP_reg(context)))-5;
 213         WORD            xcs = CS_reg(context);
 214         SNOOP16_DLL     *dll = firstdll;
 215         SNOOP16_FUN     *fun = NULL;
 216         SNOOP16_RETURNENTRIES   **rets = &firstrets;
 217         SNOOP16_RETURNENTRY     *ret;
 218         int             i,max;
 219
 220         while (dll) {
 221                 if (xcs == dll->funhandle) {
 222                         fun = (SNOOP16_FUN*)entry;
 223                         ordinal = fun-dll->funs;
 224                         break;
 225                 }
 226                 dll=dll->next;
 227         }
 228         if (!dll) {
 229                 FIXME("entrypoint 0x%08lx not found\n",entry);
 230                 return; /* oops */
 231         }
 232         while (*rets) {
 233                 for (i=0;i<sizeof((*rets)->entry)/sizeof((*rets)->entry[0]);i++)
 234                         if (!(*rets)->entry[i].origreturn)
 235                                 break;
 236                 if (i!=sizeof((*rets)->entry)/sizeof((*rets)->entry[0]))
 237                         break;
 238                 rets = &((*rets)->next);
 239         }
 240         if (!*rets) {
 241                 HANDLE16        hand = GlobalHandleToSel16(GLOBAL_Alloc(GMEM_ZEROINIT,65535,0,TRUE,FALSE,FALSE));
 242                 *rets = GlobalLock16(hand);
 243                 memset(*rets,0,65535);
 244                 (*rets)->rethandle = hand;
 245                 i = 0;  /* entry 0 is free */
 246         }
 247         ret = &((*rets)->entry[i]);
 248         ret->lcall      = 0x9a;
 249         ret->snr        = MAKELONG(sizeof(SNOOP16_RELAY),xsnr);
 250         ret->origreturn = (FARPROC16)CALLER1REF;
 251         CALLER1REF      = MAKELONG((char*)&(ret->lcall)-(char*)((*rets)->entry),(*rets)->rethandle);
 252         ret->dll        = dll;
 253         ret->args       = NULL;
 254         ret->ordinal    = ordinal;
 255         ret->origSP     = LOWORD(ESP_reg(context));
 256
 257         EIP_reg(context)= LOWORD(fun->origfun);
 258         CS_reg(context) = HIWORD(fun->origfun);
 259
 260
 261         DPRINTF("CALL %s.%ld: %s(",dll->name,ordinal,fun->name);
 262         if (fun->nrofargs>0) {
 263                 max = fun->nrofargs;
 264                 if (max>16) max=16;
 265                 for (i=max;i--;)
 266                         DPRINTF("%04x%s",*(WORD*)((char *) PTR_SEG_OFF_TO_LIN(SS_reg(context),LOWORD(ESP_reg(context)))+8+sizeof(WORD)*i),i?",":"");
 267                 if (max!=fun->nrofargs)
 268                         DPRINTF(" ...");
 269         } else if (fun->nrofargs<0) {
 270                 DPRINTF("<unknown, check return>");
 271                 ret->args = HeapAlloc(GetProcessHeap(),0,16*sizeof(WORD));
 272                 memcpy(ret->args,(LPBYTE)((char *) PTR_SEG_OFF_TO_LIN(SS_reg(context),LOWORD(ESP_reg(context)))+8),sizeof(WORD)*16);
 273         }
 274         DPRINTF(") ret=%04x:%04x\n",HIWORD(ret->origreturn),LOWORD(ret->origreturn));
 275 }
 276
 277 void WINAPI SNOOP16_Return(FARPROC proc, LPBYTE args, CONTEXT86 *context) {
 278         SNOOP16_RETURNENTRY     *ret = (SNOOP16_RETURNENTRY*)((char *) PTR_SEG_OFF_TO_LIN(CS_reg(context),LOWORD(EIP_reg(context)))-5);
 279
 280         /* We haven't found out the nrofargs yet. If we called a cdecl
 281          * function it is too late anyway and we can just set '0' (which
 282          * will be the difference between orig and current SP
 283          * If pascal -> everything ok.
 284          */
 285         if (ret->dll->funs[ret->ordinal].nrofargs<0) {
 286                 ret->dll->funs[ret->ordinal].nrofargs=(LOWORD(ESP_reg(context))-ret->origSP-4)/2;
 287         }
 288         EIP_reg(context) = LOWORD(ret->origreturn);
 289         CS_reg(context)  = HIWORD(ret->origreturn);
 290         if (ret->args) {
 291                 int     i,max;
 292
 293                 DPRINTF("RET  %s.%ld: %s(",ret->dll->name,ret->ordinal,ret->dll->funs[ret->ordinal].name);
 294                 max = ret->dll->funs[ret->ordinal].nrofargs;
 295                 if (max>16)
 296                         max=16;
 297                 if (max<0)
 298                         max=0;
 299
 300                 for (i=max;i--;)
 301                         DPRINTF("%04x%s",ret->args[i],i?",":"");
 302                 if (max!=ret->dll->funs[ret->ordinal].nrofargs)
 303                         DPRINTF(" ...");
 304                 DPRINTF(") retval = %04x:%04x ret=%04x:%04x\n",
 305                         DX_reg(context),AX_reg(context),HIWORD(ret->origreturn),LOWORD(ret->origreturn)
 306                 );
 307                 HeapFree(GetProcessHeap(),0,ret->args);
 308                 ret->args = NULL;
 309         } else
 310                 DPRINTF("RET  %s.%ld: %s() retval = %04x:%04x ret=%04x:%04x\n",
 311                         ret->dll->name,ret->ordinal,ret->dll->funs[ret->ordinal].name,
 312                         DX_reg(context),AX_reg(context),HIWORD(ret->origreturn),LOWORD(ret->origreturn)
 313                 );
 314         ret->origreturn = NULL; /* mark as empty */
 315 }
 316 #else   /* !__i386__ */
 317 void SNOOP16_RegisterDLL(NE_MODULE *pModule,LPCSTR name) {
 318         FIXME("snooping works only on i386 for now.\n");
 319         return;
 320 }
 321
 322 FARPROC16 SNOOP16_GetProcAddress16(HMODULE16 hmod,DWORD ordinal,FARPROC16 origfun) {
 323         return origfun;
 324 }
 325 #endif  /* !__i386__ */
 326