relay32/snoop.c

   1 /*
   2  * 386-specific Win32 dll<->dll snooping functions
   3  *
   4  * Copyright 1998 Marcus Meissner
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "config.h"
  22 #include "wine/port.h"
  23
  24 #include <assert.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include "winbase.h"
  28 #include "winnt.h"
  29 #include "snoop.h"
  30 #include "stackframe.h"
  31 #include "wine/debug.h"
  32 #include "wine/exception.h"
  33 #include "msvcrt/excpt.h"
  34
  35 WINE_DEFAULT_DEBUG_CHANNEL(snoop);
  36
  37 static WINE_EXCEPTION_FILTER(page_fault)
  38 {
  39     if (GetExceptionCode() == EXCEPTION_ACCESS_VIOLATION ||
  40         GetExceptionCode() == EXCEPTION_PRIV_INSTRUCTION)
  41         return EXCEPTION_EXECUTE_HANDLER;
  42     return EXCEPTION_CONTINUE_SEARCH;
  43 }
  44
  45 char **debug_snoop_excludelist = NULL, **debug_snoop_includelist = NULL;
  46
  47 #ifdef __i386__
  48
  49 extern void WINAPI SNOOP_Entry();
  50 extern void WINAPI SNOOP_Return();
  51
  52 #ifdef NEED_UNDERSCORE_PREFIX
  53 # define PREFIX "_"
  54 #else
  55 # define PREFIX
  56 #endif
  57
  58 #include "pshpack1.h"
  59
  60 typedef struct tagSNOOP_FUN {
  61         /* code part */
  62         BYTE            lcall;          /* 0xe8 call snoopentry (relative) */
  63         /* NOTE: If you move snoopentry OR nrofargs fix the relative offset
  64          * calculation!
  65          */
  66         DWORD           snoopentry;     /* SNOOP_Entry relative */
  67         /* unreached */
  68         int             nrofargs;
  69         FARPROC origfun;
  70         char            *name;
  71 } SNOOP_FUN;
  72
  73 typedef struct tagSNOOP_DLL {
  74         HMODULE hmod;
  75         SNOOP_FUN       *funs;
  76         DWORD           ordbase;
  77         DWORD           nrofordinals;
  78         struct tagSNOOP_DLL     *next;
  79         char name[1];
  80 } SNOOP_DLL;
  81
  82 typedef struct tagSNOOP_RETURNENTRY {
  83         /* code part */
  84         BYTE            lcall;          /* 0xe8 call snoopret relative*/
  85         /* NOTE: If you move snoopret OR origreturn fix the relative offset
  86          * calculation!
  87          */
  88         DWORD           snoopret;       /* SNOOP_Ret relative */
  89         /* unreached */
  90         FARPROC origreturn;
  91         SNOOP_DLL       *dll;
  92         DWORD           ordinal;
  93         DWORD           origESP;
  94         DWORD           *args;          /* saved args across a stdcall */
  95 } SNOOP_RETURNENTRY;
  96
  97 typedef struct tagSNOOP_RETURNENTRIES {
  98         SNOOP_RETURNENTRY entry[4092/sizeof(SNOOP_RETURNENTRY)];
  99         struct tagSNOOP_RETURNENTRIES   *next;
 100 } SNOOP_RETURNENTRIES;
 101
 102 #include "poppack.h"
 103
 104 static  SNOOP_DLL               *firstdll = NULL;
 105 static  SNOOP_RETURNENTRIES     *firstrets = NULL;
 106
 107 /***********************************************************************
 108  *          SNOOP_ShowDebugmsgSnoop
 109  *
 110  * Simple function to decide if a particular debugging message is
 111  * wanted.
 112  */
 113 int SNOOP_ShowDebugmsgSnoop(const char *dll, int ord, const char *fname) {
 114
 115   if(debug_snoop_excludelist || debug_snoop_includelist) {
 116     char **listitem;
 117     char buf[80];
 118     int len, len2, itemlen, show;
 119
 120     if(debug_snoop_excludelist) {
 121       show = 1;
 122       listitem = debug_snoop_excludelist;
 123     } else {
 124       show = 0;
 125       listitem = debug_snoop_includelist;
 126     }
 127     len = strlen(dll);
 128     assert(len < 64);
 129     sprintf(buf, "%s.%d", dll, ord);
 130     len2 = strlen(buf);
 131     for(; *listitem; listitem++) {
 132       itemlen = strlen(*listitem);
 133       if((itemlen == len && !strncasecmp(*listitem, buf, len)) ||
 134          (itemlen == len2 && !strncasecmp(*listitem, buf, len2)) ||
 135          !strcasecmp(*listitem, fname)) {
 136         show = !show;
 137        break;
 138       }
 139     }
 140     return show;
 141   }
 142   return 1;
 143 }
 144
 145 void
 146 SNOOP_RegisterDLL(HMODULE hmod,LPCSTR name,DWORD ordbase,DWORD nrofordinals) {
 147         SNOOP_DLL       **dll = &(firstdll);
 148         char            *s;
 149
 150     TRACE("hmod=%x, name=%s, ordbase=%ld, nrofordinals=%ld\n",
 151            hmod, name, ordbase, nrofordinals);
 152
 153         if (!TRACE_ON(snoop)) return;
 154         while (*dll) {
 155                 if ((*dll)->hmod == hmod)
 156                 {
 157                     /* another dll, loaded at the same address */
 158                     VirtualFree((*dll)->funs, (*dll)->nrofordinals*sizeof(SNOOP_FUN), MEM_RELEASE);
 159                     break;
 160                 }
 161                 dll = &((*dll)->next);
 162         }
 163         *dll = HeapReAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, *dll, sizeof(SNOOP_DLL)+strlen(name));
 164         (*dll)->hmod    = hmod;
 165         (*dll)->ordbase = ordbase;
 166         (*dll)->nrofordinals = nrofordinals;
 167         strcpy( (*dll)->name, name );
 168         if ((s=strrchr((*dll)->name,'.')))
 169                 *s='\0';
 170         (*dll)->funs = VirtualAlloc(NULL,nrofordinals*sizeof(SNOOP_FUN),MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
 171         memset((*dll)->funs,0,nrofordinals*sizeof(SNOOP_FUN));
 172         if (!(*dll)->funs) {
 173                 HeapFree(GetProcessHeap(),0,*dll);
 174                 FIXME("out of memory\n");
 175                 return;
 176         }
 177 }
 178
 179 FARPROC
 180 SNOOP_GetProcAddress(HMODULE hmod,LPCSTR name,DWORD ordinal,FARPROC origfun) {
 181         SNOOP_DLL                       *dll = firstdll;
 182         SNOOP_FUN                       *fun;
 183         int                             j;
 184         IMAGE_SECTION_HEADER            *pe_seg = PE_SECTIONS(hmod);
 185
 186         if (!TRACE_ON(snoop)) return origfun;
 187         if (!*(LPBYTE)origfun) /* 0x00 is an imposs. opcode, poss. dataref. */
 188                 return origfun;
 189         for (j=0;j<PE_HEADER(hmod)->FileHeader.NumberOfSections;j++)
 190                 /* 0x42 is special ELF loader tag */
 191                 if ((pe_seg[j].VirtualAddress==0x42) ||
 192                     (((DWORD)origfun-hmod>=pe_seg[j].VirtualAddress)&&
 193                      ((DWORD)origfun-hmod <pe_seg[j].VirtualAddress+
 194                                    pe_seg[j].SizeOfRawData
 195                    ))
 196                 )
 197                         break;
 198         /* If we looked through all sections (and didn't find one)
 199          * or if the sectionname contains "data", we return the
 200          * original function since it is most likely a datareference.
 201          */
 202         if (    (j==PE_HEADER(hmod)->FileHeader.NumberOfSections)       ||
 203                 (strstr(pe_seg[j].Name,"data"))                         ||
 204                 !(pe_seg[j].Characteristics & IMAGE_SCN_CNT_CODE)
 205         )
 206                 return origfun;
 207
 208         while (dll) {
 209                 if (hmod == dll->hmod)
 210                         break;
 211                 dll=dll->next;
 212         }
 213         if (!dll)       /* probably internal */
 214                 return origfun;
 215         if (!SNOOP_ShowDebugmsgSnoop(dll->name,ordinal,name))
 216                 return origfun;
 217         assert(ordinal < dll->nrofordinals);
 218         fun = dll->funs+ordinal;
 219         if (!fun->name)
 220           {
 221             fun->name = HeapAlloc(GetProcessHeap(),0,strlen(name)+1);
 222             strcpy( fun->name, name );
 223             fun->lcall  = 0xe8;
 224             /* NOTE: origreturn struct member MUST come directly after snoopentry */
 225             fun->snoopentry     = (char*)SNOOP_Entry-((char*)(&fun->nrofargs));
 226             fun->origfun        = origfun;
 227             fun->nrofargs       = -1;
 228           }
 229         return (FARPROC)&(fun->lcall);
 230 }
 231
 232 static void SNOOP_PrintArg(DWORD x)
 233 {
 234     int i,nostring;
 235
 236     DPRINTF("%08lx",x);
 237     if ( !HIWORD(x) ) return; /* trivial reject to avoid faults */
 238     __TRY
 239     {
 240         LPBYTE s=(LPBYTE)x;
 241         i=0;nostring=0;
 242         while (i<80) {
 243             if (s[i]==0) break;
 244             if (s[i]<0x20) {nostring=1;break;}
 245             if (s[i]>=0x80) {nostring=1;break;}
 246             i++;
 247         }
 248         if (!nostring && i > 5)
 249             DPRINTF(" %s",debugstr_an((LPSTR)x,i));
 250         else  /* try unicode */
 251         {
 252             LPWSTR s=(LPWSTR)x;
 253             i=0;nostring=0;
 254             while (i<80) {
 255                 if (s[i]==0) break;
 256                 if (s[i]<0x20) {nostring=1;break;}
 257                 if (s[i]>0x100) {nostring=1;break;}
 258                 i++;
 259             }
 260             if (!nostring && i > 5) DPRINTF(" %s",debugstr_wn((LPWSTR)x,i));
 261         }
 262     }
 263     __EXCEPT(page_fault)
 264     {
 265     }
 266     __ENDTRY
 267 }
 268
 269 #define CALLER1REF (*(DWORD*)context->Esp)
 270
 271 void WINAPI SNOOP_DoEntry( CONTEXT86 *context )
 272 {
 273         DWORD           ordinal=0,entry = context->Eip - 5;
 274         SNOOP_DLL       *dll = firstdll;
 275         SNOOP_FUN       *fun = NULL;
 276         SNOOP_RETURNENTRIES     **rets = &firstrets;
 277         SNOOP_RETURNENTRY       *ret;
 278         int             i=0, max;
 279
 280         while (dll) {
 281                 if (    ((char*)entry>=(char*)dll->funs)        &&
 282                         ((char*)entry<=(char*)(dll->funs+dll->nrofordinals))
 283                 ) {
 284                         fun = (SNOOP_FUN*)entry;
 285                         ordinal = fun-dll->funs;
 286                         break;
 287                 }
 288                 dll=dll->next;
 289         }
 290         if (!dll) {
 291                 FIXME("entrypoint 0x%08lx not found\n",entry);
 292                 return; /* oops */
 293         }
 294         /* guess cdecl ... */
 295         if (fun->nrofargs<0) {
 296                 /* Typical cdecl return frame is:
 297                  *      add esp, xxxxxxxx
 298                  * which has (for xxxxxxxx up to 255 the opcode "83 C4 xx".
 299                  * (after that 81 C2 xx xx xx xx)
 300                  */
 301                 LPBYTE  reteip = (LPBYTE)CALLER1REF;
 302
 303                 if (reteip) {
 304                         if ((reteip[0]==0x83)&&(reteip[1]==0xc4))
 305                                 fun->nrofargs=reteip[2]/4;
 306                 }
 307         }
 308
 309
 310         while (*rets) {
 311                 for (i=0;i<sizeof((*rets)->entry)/sizeof((*rets)->entry[0]);i++)
 312                         if (!(*rets)->entry[i].origreturn)
 313                                 break;
 314                 if (i!=sizeof((*rets)->entry)/sizeof((*rets)->entry[0]))
 315                         break;
 316                 rets = &((*rets)->next);
 317         }
 318         if (!*rets) {
 319                 *rets = VirtualAlloc(NULL,4096,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
 320                 memset(*rets,0,4096);
 321                 i = 0;  /* entry 0 is free */
 322         }
 323         ret = &((*rets)->entry[i]);
 324         ret->lcall      = 0xe8;
 325         /* NOTE: origreturn struct member MUST come directly after snoopret */
 326         ret->snoopret   = ((char*)SNOOP_Return)-(char*)(&ret->origreturn);
 327         ret->origreturn = (FARPROC)CALLER1REF;
 328         CALLER1REF      = (DWORD)&ret->lcall;
 329         ret->dll        = dll;
 330         ret->args       = NULL;
 331         ret->ordinal    = ordinal;
 332         ret->origESP    = context->Esp;
 333
 334         context->Eip = (DWORD)fun->origfun;
 335
 336         DPRINTF("%08lx:CALL %s.%ld: %s(",GetCurrentThreadId(),dll->name,dll->ordbase+ordinal,fun->name);
 337         if (fun->nrofargs>0) {
 338                 max = fun->nrofargs; if (max>16) max=16;
 339                 for (i=0;i<max;i++)
 340                 {
 341                     SNOOP_PrintArg(*(DWORD*)(context->Esp + 4 + sizeof(DWORD)*i));
 342                     if (i<fun->nrofargs-1) DPRINTF(",");
 343                 }
 344                 if (max!=fun->nrofargs)
 345                         DPRINTF(" ...");
 346         } else if (fun->nrofargs<0) {
 347                 DPRINTF("<unknown, check return>");
 348                 ret->args = HeapAlloc(GetProcessHeap(),0,16*sizeof(DWORD));
 349                 memcpy(ret->args,(LPBYTE)(context->Esp + 4),sizeof(DWORD)*16);
 350         }
 351         DPRINTF(") ret=%08lx\n",(DWORD)ret->origreturn);
 352 }
 353
 354
 355 void WINAPI SNOOP_DoReturn( CONTEXT86 *context )
 356 {
 357         SNOOP_RETURNENTRY       *ret = (SNOOP_RETURNENTRY*)(context->Eip - 5);
 358
 359         /* We haven't found out the nrofargs yet. If we called a cdecl
 360          * function it is too late anyway and we can just set '0' (which
 361          * will be the difference between orig and current ESP
 362          * If stdcall -> everything ok.
 363          */
 364         if (ret->dll->funs[ret->ordinal].nrofargs<0)
 365                 ret->dll->funs[ret->ordinal].nrofargs=(context->Esp - ret->origESP-4)/4;
 366         context->Eip = (DWORD)ret->origreturn;
 367         if (ret->args) {
 368                 int     i,max;
 369
 370                 DPRINTF("%08lx:RET  %s.%ld: %s(",
 371                         GetCurrentThreadId(),
 372                         ret->dll->name,ret->dll->ordbase+ret->ordinal,ret->dll->funs[ret->ordinal].name);
 373                 max = ret->dll->funs[ret->ordinal].nrofargs;
 374                 if (max>16) max=16;
 375
 376                 for (i=0;i<max;i++)
 377                 {
 378                     SNOOP_PrintArg(ret->args[i]);
 379                     if (i<max-1) DPRINTF(",");
 380                 }
 381                 DPRINTF(") retval = %08lx ret=%08lx\n",
 382                         context->Eax,(DWORD)ret->origreturn );
 383                 HeapFree(GetProcessHeap(),0,ret->args);
 384                 ret->args = NULL;
 385         } else
 386                 DPRINTF("%08lx:RET  %s.%ld: %s() retval = %08lx ret=%08lx\n",
 387                         GetCurrentThreadId(),
 388                         ret->dll->name,ret->dll->ordbase+ret->ordinal,ret->dll->funs[ret->ordinal].name,
 389                         context->Eax, (DWORD)ret->origreturn);
 390         ret->origreturn = NULL; /* mark as empty */
 391 }
 392
 393 /* assembly wrappers that save the context */
 394 __ASM_GLOBAL_FUNC( SNOOP_Entry,
 395                    "call " __ASM_NAME("__wine_call_from_32_regs") "\n\t"
 396                    ".long " __ASM_NAME("SNOOP_DoEntry") ",0" );
 397 __ASM_GLOBAL_FUNC( SNOOP_Return,
 398                    "call " __ASM_NAME("__wine_call_from_32_regs") "\n\t"
 399                    ".long " __ASM_NAME("SNOOP_DoReturn") ",0" );
 400
 401 #else   /* !__i386__ */
 402 void SNOOP_RegisterDLL(HMODULE hmod,LPCSTR name,DWORD nrofordinals, DWORD dw) {
 403         if (!TRACE_ON(snoop)) return;
 404         FIXME("snooping works only on i386 for now.\n");
 405 }
 406
 407 FARPROC SNOOP_GetProcAddress(HMODULE hmod,LPCSTR name,DWORD ordinal,FARPROC origfun) {
 408         return origfun;
 409 }
 410 #endif  /* !__i386__ */