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 "winternl.h"
  28 #include "snoop.h"
  29 #include "wine/debug.h"
  30 #include "wine/exception.h"
  31 #include "excpt.h"
  32 #include "ntdll_misc.h"
  33
  34 WINE_DEFAULT_DEBUG_CHANNEL(snoop);
  35 WINE_DECLARE_DEBUG_CHANNEL(seh);
  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         void            *addr;
 145         SIZE_T          size;
 146
 147     TRACE("hmod=%p, name=%s, ordbase=%ld, nrofordinals=%ld\n",
 148            hmod, name, ordbase, nrofordinals);
 149
 150         if (!TRACE_ON(snoop)) return;
 151         while (*dll) {
 152                 if ((*dll)->hmod == hmod)
 153                 {
 154                     /* another dll, loaded at the same address */
 155                     addr = (*dll)->funs;
 156                     size = (*dll)->nrofordinals * sizeof(SNOOP_FUN);
 157                     NtFreeVirtualMemory(GetCurrentProcess(), &addr, &size, MEM_RELEASE);
 158                     break;
 159                 }
 160                 dll = &((*dll)->next);
 161         }
 162         *dll = RtlReAllocateHeap(ntdll_get_process_heap(),
 163                                  HEAP_ZERO_MEMORY, *dll,
 164                                  sizeof(SNOOP_DLL) + strlen(name));
 165         (*dll)->hmod    = hmod;
 166         (*dll)->ordbase = ordbase;
 167         (*dll)->nrofordinals = nrofordinals;
 168         strcpy( (*dll)->name, name );
 169         if ((s=strrchr((*dll)->name,'.')))
 170                 *s='\0';
 171         size = nrofordinals * sizeof(SNOOP_FUN);
 172         NtAllocateVirtualMemory(GetCurrentProcess(), &addr, NULL, &size,
 173                                 MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
 174         if (!addr) {
 175                 RtlFreeHeap(ntdll_get_process_heap(),0,*dll);
 176                 FIXME("out of memory\n");
 177                 return;
 178         }
 179         (*dll)->funs = addr;
 180         memset((*dll)->funs,0,size);
 181 }
 182
 183 FARPROC
 184 SNOOP_GetProcAddress(HMODULE hmod,LPCSTR name,DWORD ordinal,FARPROC origfun) {
 185         SNOOP_DLL                       *dll = firstdll;
 186         SNOOP_FUN                       *fun;
 187         IMAGE_SECTION_HEADER *sec;
 188
 189         if (!TRACE_ON(snoop)) return origfun;
 190         if (!*(LPBYTE)origfun) /* 0x00 is an imposs. opcode, poss. dataref. */
 191                 return origfun;
 192
 193         sec = RtlImageRvaToSection( RtlImageNtHeader(hmod), hmod, (char *)origfun - (char *)hmod );
 194
 195         if (!sec || !(sec->Characteristics & IMAGE_SCN_CNT_CODE))
 196             return origfun;  /* most likely a data reference */
 197
 198         while (dll) {
 199                 if (hmod == dll->hmod)
 200                         break;
 201                 dll=dll->next;
 202         }
 203         if (!dll)       /* probably internal */
 204                 return origfun;
 205         if (!SNOOP_ShowDebugmsgSnoop(dll->name,ordinal,name))
 206                 return origfun;
 207         assert(ordinal < dll->nrofordinals);
 208         fun = dll->funs+ordinal;
 209         if (!fun->name)
 210           {
 211             fun->name = RtlAllocateHeap(ntdll_get_process_heap(),0,strlen(name)+1);
 212             strcpy( fun->name, name );
 213             fun->lcall  = 0xe8;
 214             /* NOTE: origreturn struct member MUST come directly after snoopentry */
 215             fun->snoopentry     = (char*)SNOOP_Entry-((char*)(&fun->nrofargs));
 216             fun->origfun        = origfun;
 217             fun->nrofargs       = -1;
 218           }
 219         return (FARPROC)&(fun->lcall);
 220 }
 221
 222 static void SNOOP_PrintArg(DWORD x)
 223 {
 224     int i,nostring;
 225
 226     DPRINTF("%08lx",x);
 227     if (!HIWORD(x) || TRACE_ON(seh)) return; /* trivial reject to avoid faults */
 228     __TRY
 229     {
 230         LPBYTE s=(LPBYTE)x;
 231         i=0;nostring=0;
 232         while (i<80) {
 233             if (s[i]==0) break;
 234             if (s[i]<0x20) {nostring=1;break;}
 235             if (s[i]>=0x80) {nostring=1;break;}
 236             i++;
 237         }
 238         if (!nostring && i > 5)
 239             DPRINTF(" %s",debugstr_an((LPSTR)x,i));
 240         else  /* try unicode */
 241         {
 242             LPWSTR s=(LPWSTR)x;
 243             i=0;nostring=0;
 244             while (i<80) {
 245                 if (s[i]==0) break;
 246                 if (s[i]<0x20) {nostring=1;break;}
 247                 if (s[i]>0x100) {nostring=1;break;}
 248                 i++;
 249             }
 250             if (!nostring && i > 5) DPRINTF(" %s",debugstr_wn((LPWSTR)x,i));
 251         }
 252     }
 253     __EXCEPT(page_fault)
 254     {
 255     }
 256     __ENDTRY
 257 }
 258
 259 #define CALLER1REF (*(DWORD*)context->Esp)
 260
 261 void WINAPI SNOOP_DoEntry( CONTEXT86 *context )
 262 {
 263         DWORD           ordinal=0,entry = context->Eip - 5;
 264         SNOOP_DLL       *dll = firstdll;
 265         SNOOP_FUN       *fun = NULL;
 266         SNOOP_RETURNENTRIES     **rets = &firstrets;
 267         SNOOP_RETURNENTRY       *ret;
 268         int             i=0, max;
 269
 270         while (dll) {
 271                 if (    ((char*)entry>=(char*)dll->funs)        &&
 272                         ((char*)entry<=(char*)(dll->funs+dll->nrofordinals))
 273                 ) {
 274                         fun = (SNOOP_FUN*)entry;
 275                         ordinal = fun-dll->funs;
 276                         break;
 277                 }
 278                 dll=dll->next;
 279         }
 280         if (!dll) {
 281                 FIXME("entrypoint 0x%08lx not found\n",entry);
 282                 return; /* oops */
 283         }
 284         /* guess cdecl ... */
 285         if (fun->nrofargs<0) {
 286                 /* Typical cdecl return frame is:
 287                  *      add esp, xxxxxxxx
 288                  * which has (for xxxxxxxx up to 255 the opcode "83 C4 xx".
 289                  * (after that 81 C2 xx xx xx xx)
 290                  */
 291                 LPBYTE  reteip = (LPBYTE)CALLER1REF;
 292
 293                 if (reteip) {
 294                         if ((reteip[0]==0x83)&&(reteip[1]==0xc4))
 295                                 fun->nrofargs=reteip[2]/4;
 296                 }
 297         }
 298
 299
 300         while (*rets) {
 301                 for (i=0;i<sizeof((*rets)->entry)/sizeof((*rets)->entry[0]);i++)
 302                         if (!(*rets)->entry[i].origreturn)
 303                                 break;
 304                 if (i!=sizeof((*rets)->entry)/sizeof((*rets)->entry[0]))
 305                         break;
 306                 rets = &((*rets)->next);
 307         }
 308         if (!*rets) {
 309                 SIZE_T size = 4096;
 310                 VOID* addr;
 311
 312                 NtAllocateVirtualMemory(GetCurrentProcess(), &addr, NULL, &size,
 313                                         MEM_COMMIT | MEM_RESERVE,
 314                                         PAGE_EXECUTE_READWRITE);
 315                 if (!addr) return;
 316                 *rets = addr;
 317                 memset(*rets,0,4096);
 318                 i = 0;  /* entry 0 is free */
 319         }
 320         ret = &((*rets)->entry[i]);
 321         ret->lcall      = 0xe8;
 322         /* NOTE: origreturn struct member MUST come directly after snoopret */
 323         ret->snoopret   = ((char*)SNOOP_Return)-(char*)(&ret->origreturn);
 324         ret->origreturn = (FARPROC)CALLER1REF;
 325         CALLER1REF      = (DWORD)&ret->lcall;
 326         ret->dll        = dll;
 327         ret->args       = NULL;
 328         ret->ordinal    = ordinal;
 329         ret->origESP    = context->Esp;
 330
 331         context->Eip = (DWORD)fun->origfun;
 332
 333         DPRINTF("%04lx:CALL %s.%ld: %s(",GetCurrentThreadId(),dll->name,dll->ordbase+ordinal,fun->name);
 334         if (fun->nrofargs>0) {
 335                 max = fun->nrofargs; if (max>16) max=16;
 336                 for (i=0;i<max;i++)
 337                 {
 338                     SNOOP_PrintArg(*(DWORD*)(context->Esp + 4 + sizeof(DWORD)*i));
 339                     if (i<fun->nrofargs-1) DPRINTF(",");
 340                 }
 341                 if (max!=fun->nrofargs)
 342                         DPRINTF(" ...");
 343         } else if (fun->nrofargs<0) {
 344                 DPRINTF("<unknown, check return>");
 345                 ret->args = RtlAllocateHeap(ntdll_get_process_heap(),
 346                                             0,16*sizeof(DWORD));
 347                 memcpy(ret->args,(LPBYTE)(context->Esp + 4),sizeof(DWORD)*16);
 348         }
 349         DPRINTF(") ret=%08lx\n",(DWORD)ret->origreturn);
 350 }
 351
 352
 353 void WINAPI SNOOP_DoReturn( CONTEXT86 *context )
 354 {
 355         SNOOP_RETURNENTRY       *ret = (SNOOP_RETURNENTRY*)(context->Eip - 5);
 356
 357         /* We haven't found out the nrofargs yet. If we called a cdecl
 358          * function it is too late anyway and we can just set '0' (which
 359          * will be the difference between orig and current ESP
 360          * If stdcall -> everything ok.
 361          */
 362         if (ret->dll->funs[ret->ordinal].nrofargs<0)
 363                 ret->dll->funs[ret->ordinal].nrofargs=(context->Esp - ret->origESP-4)/4;
 364         context->Eip = (DWORD)ret->origreturn;
 365         if (ret->args) {
 366                 int     i,max;
 367
 368                 DPRINTF("%04lx:RET  %s.%ld: %s(",
 369                         GetCurrentThreadId(),
 370                         ret->dll->name,ret->dll->ordbase+ret->ordinal,ret->dll->funs[ret->ordinal].name);
 371                 max = ret->dll->funs[ret->ordinal].nrofargs;
 372                 if (max>16) max=16;
 373
 374                 for (i=0;i<max;i++)
 375                 {
 376                     SNOOP_PrintArg(ret->args[i]);
 377                     if (i<max-1) DPRINTF(",");
 378                 }
 379                 DPRINTF(") retval = %08lx ret=%08lx\n",
 380                         context->Eax,(DWORD)ret->origreturn );
 381                 RtlFreeHeap(ntdll_get_process_heap(),0,ret->args);
 382                 ret->args = NULL;
 383         } else
 384                 DPRINTF("%04lx:RET  %s.%ld: %s() retval = %08lx ret=%08lx\n",
 385                         GetCurrentThreadId(),
 386                         ret->dll->name,ret->dll->ordbase+ret->ordinal,ret->dll->funs[ret->ordinal].name,
 387                         context->Eax, (DWORD)ret->origreturn);
 388         ret->origreturn = NULL; /* mark as empty */
 389 }
 390
 391 /* assembly wrappers that save the context */
 392 __ASM_GLOBAL_FUNC( SNOOP_Entry,
 393                    "call " __ASM_NAME("__wine_call_from_32_regs") "\n\t"
 394                    ".long " __ASM_NAME("SNOOP_DoEntry") ",0" );
 395 __ASM_GLOBAL_FUNC( SNOOP_Return,
 396                    "call " __ASM_NAME("__wine_call_from_32_regs") "\n\t"
 397                    ".long " __ASM_NAME("SNOOP_DoReturn") ",0" );
 398
 399 #else   /* !__i386__ */
 400 void SNOOP_RegisterDLL(HMODULE hmod,LPCSTR name,DWORD nrofordinals, DWORD dw) {
 401         if (!TRACE_ON(snoop)) return;
 402         FIXME("snooping works only on i386 for now.\n");
 403 }
 404
 405 FARPROC SNOOP_GetProcAddress(HMODULE hmod,LPCSTR name,DWORD ordinal,FARPROC origfun) {
 406         return origfun;
 407 }
 408 #endif  /* !__i386__ */