loader/elf.c

   1 /*
   2  *      UNIX dynamic loader
   3  *
   4  * Currently only supports stuff using the dl* API.
   5  *
   6  * Copyright 1998 Marcus Meissner
   7  *
   8  * FIXME:       Small reentrancy problem.
   9  * IDEA(s):     could be used to split up shell32,comctl32...
  10  */
  11
  12 #include "config.h"
  13
  14 #include <assert.h>
  15 #include <stdio.h>
  16 #include <string.h>
  17 #include <sys/types.h>
  18
  19 #include "windows.h"
  20 #include "snoop.h"
  21 #include "process.h"
  22 #include "neexe.h"
  23 #include "peexe.h"
  24 #include "heap.h"
  25 #include "pe_image.h"
  26 #include "module.h"
  27 #include "debug.h"
  28
  29 WINE_MODREF *
  30 ELF_CreateDummyModule( LPCSTR libname, LPCSTR modname, PDB32 *process )
  31 {
  32         PIMAGE_DOS_HEADER       dh;
  33         PIMAGE_NT_HEADERS       nth;
  34         PIMAGE_SECTION_HEADER   sh;
  35         WINE_MODREF *wm;
  36         HMODULE32 hmod;
  37
  38         wm=(WINE_MODREF*)HeapAlloc(process->heap,HEAP_ZERO_MEMORY,sizeof(*wm));
  39         wm->type = MODULE32_ELF;
  40
  41         /* FIXME: hmm, order? */
  42         wm->next = process->modref_list;
  43         process->modref_list = wm;
  44
  45         wm->modname = HEAP_strdupA(process->heap,0,modname);
  46         wm->longname = HEAP_strdupA(process->heap,0,libname);
  47
  48         hmod = (HMODULE32)HeapAlloc(process->heap,HEAP_ZERO_MEMORY,sizeof(IMAGE_DOS_HEADER)+sizeof(IMAGE_NT_HEADERS)+sizeof(IMAGE_SECTION_HEADER)+100);
  49         dh = (PIMAGE_DOS_HEADER)hmod;
  50         dh->e_magic = IMAGE_DOS_SIGNATURE;
  51         dh->e_lfanew = sizeof(IMAGE_DOS_HEADER);
  52         nth = PE_HEADER(hmod);
  53         nth->Signature = IMAGE_NT_SIGNATURE;
  54         nth->FileHeader.Machine = IMAGE_FILE_MACHINE_I386;
  55         nth->FileHeader.NumberOfSections = 1;
  56         nth->FileHeader.SizeOfOptionalHeader = sizeof(IMAGE_OPTIONAL_HEADER);
  57         nth->FileHeader.Characteristics =
  58                 IMAGE_FILE_RELOCS_STRIPPED|IMAGE_FILE_LINE_NUMS_STRIPPED|
  59                 IMAGE_FILE_LOCAL_SYMS_STRIPPED|IMAGE_FILE_32BIT_MACHINE|
  60                 IMAGE_FILE_DLL|IMAGE_FILE_DEBUG_STRIPPED;
  61         nth->OptionalHeader.Magic = IMAGE_NT_OPTIONAL_HDR_MAGIC;
  62         nth->OptionalHeader.SizeOfCode = 0;
  63         nth->OptionalHeader.SizeOfInitializedData = 0;
  64         nth->OptionalHeader.SizeOfUninitializedData = 0;
  65         nth->OptionalHeader.AddressOfEntryPoint = 0;
  66         nth->OptionalHeader.BaseOfCode          = 0;
  67         nth->OptionalHeader.MajorOperatingSystemVersion = 4;
  68         nth->OptionalHeader.MajorImageVersion   = 4;
  69         nth->OptionalHeader.SizeOfImage         = 0;
  70         nth->OptionalHeader.SizeOfHeaders       = 0;
  71         nth->OptionalHeader.Subsystem           = IMAGE_SUBSYSTEM_NATIVE;
  72         nth->OptionalHeader.DllCharacteristics  = 0;
  73         nth->OptionalHeader.NumberOfRvaAndSizes = 0;
  74
  75         /* allocate one code section that crosses the whole process range
  76          * (we could find out from internal tables ... hmm )
  77          */
  78         sh=(PIMAGE_SECTION_HEADER)(nth+1);
  79         strcpy(sh->Name,".text");
  80         sh->Misc.VirtualSize    = 0x7fffffff;
  81         sh->VirtualAddress      = 0x42; /* so snoop can use it ... */
  82         sh->SizeOfRawData       = 0x7fffffff;
  83         sh->PointerToRawData    = 0;
  84         sh->Characteristics     = IMAGE_SCN_CNT_CODE|IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_MEM_EXECUTE|IMAGE_SCN_MEM_READ;
  85         wm->module = hmod;
  86         return wm;
  87 }
  88
  89
  90 #if defined(HAVE_LIBDL) && defined(HAVE_DLFCN_H)
  91
  92 #define UNIX_DLL_ENDING         "so"
  93
  94 #define STUBSIZE                4095
  95
  96 #include <dlfcn.h>
  97
  98 HMODULE32
  99 ELF_LoadLibraryEx32A(LPCSTR libname,PDB32 *process,HANDLE32 hf,DWORD flags) {
 100         WINE_MODREF     *wm;
 101         char            *modname,*s,*t,*x;
 102         LPVOID          *dlhandle;
 103
 104         t = HeapAlloc(process->heap,HEAP_ZERO_MEMORY,strlen(libname)+strlen("lib.so")+1);
 105         *t = '\0';
 106         /* copy path to tempvar ... */
 107         s=strrchr(libname,'/');
 108         if (!s)
 109                 s=strrchr(libname,'\\');
 110         if (s) {
 111                 strncpy(t,libname,s-libname+1);
 112                 t[s-libname+1]= '\0';
 113         } else
 114                 s = (LPSTR)libname;
 115         modname = s;
 116         /* append "lib" foo ".so" */
 117         strcat(t,"lib");
 118         x = t+strlen(t);
 119         strcat(t,s);
 120         s = strchr(x,'.');
 121         while (s) {
 122                 if (!strcasecmp(s,".dll")) {
 123                         strcpy(s+1,UNIX_DLL_ENDING);
 124                         break;
 125                 }
 126                 s=strchr(s+1,'.');
 127         }
 128
 129         /* FIXME: make UNIX filename from DOS fn? */
 130
 131         /* ... and open it */
 132         dlhandle = dlopen(t,RTLD_NOW);
 133         if (!dlhandle) {
 134                 HeapFree(process->heap,0,t);
 135                 return 0;
 136         }
 137
 138         wm = ELF_CreateDummyModule( t, modname, process );
 139         wm->binfmt.elf.dlhandle = dlhandle;
 140
 141         SNOOP_RegisterDLL(wm->module,libname,STUBSIZE/sizeof(ELF_STDCALL_STUB));
 142         return wm->module;
 143 }
 144
 145 FARPROC32
 146 ELF_FindExportedFunction( PDB32 *process,WINE_MODREF *wm, LPCSTR funcName) {
 147         LPVOID                  fun;
 148         int                     i,nrofargs = 0;
 149         ELF_STDCALL_STUB        *stub;
 150
 151         assert(wm->type == MODULE32_ELF);
 152         if (!HIWORD(funcName)) {
 153                 ERR(win32,"Can't import from UNIX dynamic libs by ordinal, sorry.\n");
 154                 return (FARPROC32)0;
 155         }
 156         fun = dlsym(wm->binfmt.elf.dlhandle,funcName);
 157         /* we sometimes have an excess '_' at the beginning of the name */
 158         if (!fun && (funcName[0]=='_')) {
 159                 funcName++ ;
 160                 fun = dlsym(wm->binfmt.elf.dlhandle,funcName);
 161         }
 162         if (!fun) {
 163                 /* Function@nrofargs usually marks a stdcall function
 164                  * with nrofargs bytes that are popped at the end
 165                  */
 166                 if (strchr(funcName,'@')) {
 167                         LPSTR   t,fn = HEAP_strdupA(process->heap,0,funcName);
 168
 169                         t = strchr(fn,'@');
 170                         *t = '\0';
 171                         nrofargs = 0;
 172                         sscanf(t+1,"%d",&nrofargs);
 173                         fun = dlsym(wm->binfmt.elf.dlhandle,fn);
 174                         HeapFree(process->heap,0,fn);
 175                 }
 176         }
 177         /* We sometimes have Win32 dlls implemented using stdcall but UNIX
 178          * dlls using cdecl. If we find out the number of args the function
 179          * uses, we remove them from the stack using two small stubs.
 180          */
 181         if (!wm->binfmt.elf.stubs) {
 182                 /* one page should suffice */
 183                 wm->binfmt.elf.stubs = VirtualAlloc(NULL,STUBSIZE,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
 184                 memset(wm->binfmt.elf.stubs,0,STUBSIZE);
 185         }
 186         stub = wm->binfmt.elf.stubs;
 187         for (i=0;i<STUBSIZE/sizeof(ELF_STDCALL_STUB);i++) {
 188                 if (!stub->origfun)
 189                         break;
 190                 if (stub->origfun == (DWORD)fun)
 191                         break;
 192                 stub++;
 193         }
 194         if (i==STUBSIZE/sizeof(ELF_STDCALL_STUB)) {
 195                 ERR(win32,"please report, that there are not enough slots for stdcall stubs in the ELF loader.\n");
 196                 assert(i<STUBSIZE/sizeof(ELF_STDCALL_STUB));
 197         }
 198         if (!stub->origfun)
 199                 stub->origfun=(DWORD)fun; /* just a marker */
 200
 201         if (fun && nrofargs) { /* we don't need it for 0 args */
 202                 /* Selfmodifying entry/return stub for stdcall -> cdecl
 203                  * conversion.
 204                  *  - Pop returnaddress directly into our return code
 205                  *              popl <into code below>
 206                  *  - Replace it by pointer to start of our returncode
 207                  *              push $newret
 208                  *  - And call the original function
 209                  *              jmp $orgfun
 210                  *  - Remove the arguments no longer needed
 211                  * newret:      add esp, <nrofargs>
 212                  *  - Push the original returnvalue on the stack
 213                  *              pushl <poppedvalue>
 214                  *  - And return to it.
 215                  *              ret
 216                  */
 217
 218                 /* FIXME: The function stub is not reentrant. */
 219
 220                 ((LPBYTE)&(stub->popl))[0]        = 0x8f;
 221                 ((LPBYTE)&(stub->popl))[1]        = 0x05;
 222                 stub->addr_popped = (DWORD)&(stub->oldret);
 223                 stub->pushl1      = 0x68;
 224                 stub->newret      = (DWORD)&(stub->addesp);
 225                 stub->pushl2      = 0x68;
 226                 stub->origfun     = (DWORD)fun;
 227                 stub->ret1        = 0xc3;
 228                 ((LPBYTE)&(stub->addesp))[0]=0x83;
 229                 ((LPBYTE)&(stub->addesp))[1]=0xc4;
 230                 stub->nrofargs    = nrofargs;
 231                 stub->pushl3      = 0x68;
 232                         /* filled out by entrycode */
 233                 stub->oldret      = 0xdeadbeef;
 234                 stub->ret2        = 0xc3;
 235                 fun=(FARPROC32)stub;
 236         }
 237         if (!fun) {
 238                 FIXME(win32,"function %s not found: %s\n",funcName,dlerror());
 239                 return fun;
 240         }
 241         fun = SNOOP_GetProcAddress32(wm->module,funcName,stub-wm->binfmt.elf.stubs,fun);
 242         return (FARPROC32)fun;
 243 }
 244 #else
 245
 246 HMODULE32
 247 ELF_LoadLibraryEx32A(LPCSTR libname,PDB32 *process,HANDLE32 hf,DWORD flags) {
 248         return 0;
 249 }
 250 FARPROC32
 251 ELF_FindExportedFunction( PDB32 *process,WINE_MODREF *wm, LPCSTR funcName) {
 252         return (FARPROC32)0;
 253 }
 254
 255 #endif