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