loader/elf.c - wine - Git at Google

 /*
  *	UNIX dynamic loader
  *
  * Currently only supports stuff using the dl* API.
  *
  * Copyright 1998 Marcus Meissner
  *
  * FIXME: 	Small reentrancy problem.
  * IDEA(s):	could be used to split up shell32,comctl32...
  */

 #include "config.h"

 #include <assert.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/types.h>

 #include "snoop.h"
 #include "heap.h"
 #include "file.h"
 #include "module.h"
 #include "debugtools.h"
 #include "winerror.h"
 #include "wine/port.h"

 DEFAULT_DEBUG_CHANNEL(win32);

 #ifdef HAVE_DL_API

 typedef struct {
 	WORD	popl	WINE_PACKED;	/* 0x8f 0x05 */
 	DWORD	addr_popped WINE_PACKED;/* ...  */
 	BYTE	pushl1	WINE_PACKED;	/* 0x68 */
 	DWORD	newret WINE_PACKED;	/* ...  */
 	BYTE	pushl2 	WINE_PACKED;	/* 0x68 */
 	DWORD	origfun WINE_PACKED;	/* original function */
 	BYTE	ret1	WINE_PACKED;	/* 0xc3 */
 	WORD	addesp 	WINE_PACKED;	/* 0x83 0xc4 */
 	BYTE	nrofargs WINE_PACKED;	/* nr of arguments to add esp, */
 	BYTE	pushl3	WINE_PACKED;	/* 0x68 */
 	DWORD	oldret	WINE_PACKED;	/* Filled out from popl above  */
 	BYTE	ret2	WINE_PACKED;	/* 0xc3 */
 } ELF_STDCALL_STUB;

 #define UNIX_DLL_ENDING		"so"

 #define	STUBSIZE		4095
 #define STUBOFFSET  (sizeof(IMAGE_DOS_HEADER) + \
                      sizeof(IMAGE_NT_HEADERS) + \
                      sizeof(IMAGE_SECTION_HEADER))

 static FARPROC ELF_FindExportedFunction( WINE_MODREF *wm, LPCSTR funcName, BOOL snoop );

 static HMODULE ELF_CreateDummyModule( LPCSTR libname, LPCSTR modname )
 {
 	PIMAGE_DOS_HEADER	dh;
 	PIMAGE_NT_HEADERS	nth;
 	PIMAGE_SECTION_HEADER	sh;
 	HMODULE hmod;

 	hmod = (HMODULE)HeapAlloc( GetProcessHeap(), HEAP_ZERO_MEMORY,
                                      sizeof(IMAGE_DOS_HEADER) +
                                      sizeof(IMAGE_NT_HEADERS) +
                                      sizeof(IMAGE_SECTION_HEADER) + STUBSIZE );
 	dh = (PIMAGE_DOS_HEADER)hmod;
 	dh->e_magic = IMAGE_DOS_SIGNATURE;
 	dh->e_lfanew = sizeof(IMAGE_DOS_HEADER);
 	nth = PE_HEADER(hmod);
 	nth->Signature = IMAGE_NT_SIGNATURE;
 	nth->FileHeader.Machine = IMAGE_FILE_MACHINE_I386;
 	nth->FileHeader.NumberOfSections = 1;
 	nth->FileHeader.SizeOfOptionalHeader = sizeof(IMAGE_OPTIONAL_HEADER);
 	nth->FileHeader.Characteristics =
 		IMAGE_FILE_RELOCS_STRIPPED|IMAGE_FILE_LINE_NUMS_STRIPPED|
 		IMAGE_FILE_LOCAL_SYMS_STRIPPED|IMAGE_FILE_32BIT_MACHINE|
 		IMAGE_FILE_DLL|IMAGE_FILE_DEBUG_STRIPPED;
 	nth->OptionalHeader.Magic = IMAGE_NT_OPTIONAL_HDR_MAGIC;
 	nth->OptionalHeader.SizeOfCode = 0;
 	nth->OptionalHeader.SizeOfInitializedData = 0;
 	nth->OptionalHeader.SizeOfUninitializedData = 0;
 	nth->OptionalHeader.AddressOfEntryPoint	= 0;
 	nth->OptionalHeader.BaseOfCode		= 0;
 	nth->OptionalHeader.MajorOperatingSystemVersion = 4;
 	nth->OptionalHeader.MajorImageVersion	= 4;
 	nth->OptionalHeader.SizeOfImage		= 0;
 	nth->OptionalHeader.SizeOfHeaders	= 0;
 	nth->OptionalHeader.Subsystem		= IMAGE_SUBSYSTEM_NATIVE;
 	nth->OptionalHeader.DllCharacteristics	= 0;
 	nth->OptionalHeader.NumberOfRvaAndSizes	= 0;

 	/* allocate one code section that crosses the whole process range
 	 * (we could find out from internal tables ... hmm )
 	 */
 	sh=(PIMAGE_SECTION_HEADER)(nth+1);
 	strcpy(sh->Name,".text");
 	sh->Misc.VirtualSize	= STUBSIZE;
 	sh->VirtualAddress	= STUBOFFSET; /* so snoop can use it ... */
 	sh->SizeOfRawData	= STUBSIZE;
 	sh->PointerToRawData	= 0;
 	sh->Characteristics	= IMAGE_SCN_CNT_CODE|IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_MEM_EXECUTE|IMAGE_SCN_MEM_READ;
         return hmod;
 }

 WINE_MODREF *ELF_LoadLibraryExA( LPCSTR libname, DWORD flags)
 {
 	WINE_MODREF	*wm;
         HMODULE		hmod;
 	char		*modname,*s,*t,*x;
 	LPVOID		*dlhandle;
 	char		error[256];

 	t = HeapAlloc( GetProcessHeap(), HEAP_ZERO_MEMORY,
                        strlen(libname) + strlen("lib.so") + 1 );
 	*t = '\0';
 	/* copy path to tempvar ... */
 	s=strrchr(libname,'/');
 	if (!s)
 		s=strrchr(libname,'\\');
 	if (s) {
 		s++; /* skip / or \ */
 		/* copy everything up to s-1 */
 		memcpy(t,libname,s-libname);
 		t[s-libname]= '\0';
 	} else
 		s = (LPSTR)libname;
 	modname = s;
 	/* append "lib" foo ".so" */
 	strcat(t,"lib");
 	x = t+strlen(t);
 	strcat(t,s);
 	s = strchr(x,'.');
 	if (s) {
             while (s) {
 		if (!FILE_strcasecmp(s,".dll")) {
                     strcpy(s+1,UNIX_DLL_ENDING);
                     break;
 		}
 		s=strchr(s+1,'.');
             }
 	} else {
 	    	strcat(x,"."UNIX_DLL_ENDING);
 	}

         /* grab just the last piece of the path/filename
            which should be the name of the library we are
            looking to load. increment by 1 to skip the DOS slash */
         s = strrchr(t,'\\');
         s++;

        /* ... and open the library pointed by s, while t points
          points to the ENTIRE DOS filename of the library
          t is returned by HeapAlloc() above and so is also used
          with HeapFree() below */
 	dlhandle = wine_dlopen(s,RTLD_NOW,error,sizeof(error));
 	if (!dlhandle) {
                 WARN("failed to load %s: %s\n", s, error);
 		HeapFree( GetProcessHeap(), 0, t );
 		SetLastError( ERROR_FILE_NOT_FOUND );
 		return NULL;
 	}

 	hmod = ELF_CreateDummyModule( t, modname );

 	SNOOP_RegisterDLL(hmod,libname,0,STUBSIZE/sizeof(ELF_STDCALL_STUB));

         wm = PE_CreateModule( hmod, libname, 0, 0, FALSE );
         wm->find_export = ELF_FindExportedFunction;
 	wm->dlhandle = dlhandle;
 	return wm;
 }

 static FARPROC ELF_FindExportedFunction( WINE_MODREF *wm, LPCSTR funcName, BOOL snoop )
 {
 	LPVOID			fun;
 	int			i,nrofargs = 0;
 	ELF_STDCALL_STUB	*stub, *first_stub;
 	char			error[256];

 	if (!HIWORD(funcName)) {
 		ERR("Can't import from UNIX dynamic libs by ordinal, sorry.\n");
 		return (FARPROC)0;
 	}
 	fun = wine_dlsym(wm->dlhandle,funcName,error,sizeof(error));
         if (!fun)
         {
             /* we sometimes have an excess '_' at the beginning of the name */
             if (funcName[0]=='_')
             {
 		funcName++ ;
 		fun = wine_dlsym(wm->dlhandle,funcName,error,sizeof(error));
             }
         }
 	if (!fun) {
 		/* Function@nrofargs usually marks a stdcall function
 		 * with nrofargs bytes that are popped at the end
 		 */
 		if (strchr(funcName,'@')) {
 			LPSTR	t,fn = HEAP_strdupA( GetProcessHeap(), 0, funcName );

 			t = strchr(fn,'@');
 			*t = '\0';
 			nrofargs = 0;
 			sscanf(t+1,"%d",&nrofargs);
 			fun = wine_dlsym(wm->dlhandle,fn,error,sizeof(error));
 			HeapFree( GetProcessHeap(), 0, fn );
 		}
 	}
 	/* We sometimes have Win32 dlls implemented using stdcall but UNIX
 	 * dlls using cdecl. If we find out the number of args the function
 	 * uses, we remove them from the stack using two small stubs.
 	 */
         stub = first_stub = (ELF_STDCALL_STUB *)((char *)wm->module + STUBOFFSET);
 	for (i=0;i<STUBSIZE/sizeof(ELF_STDCALL_STUB);i++) {
 		if (!stub->origfun)
 			break;
 		if (stub->origfun == (DWORD)fun)
 			break;
 		stub++;
 	}
 	if (i==STUBSIZE/sizeof(ELF_STDCALL_STUB)) {
 		ERR("please report, that there are not enough slots for stdcall stubs in the ELF loader.\n");
 		assert(i<STUBSIZE/sizeof(ELF_STDCALL_STUB));
 	}
 	if (!stub->origfun)
 		stub->origfun=(DWORD)fun; /* just a marker */

 	if (fun && nrofargs) { /* we don't need it for 0 args */
 		/* Selfmodifying entry/return stub for stdcall -> cdecl
 		 * conversion.
 		 *  - Pop returnaddress directly into our return code
 		 * 		popl <into code below>
 		 *  - Replace it by pointer to start of our returncode
 		 * 		push $newret
 		 *  - And call the original function
 		 * 		jmp $orgfun
 		 *  - Remove the arguments no longer needed
 		 * newret: 	add esp, <nrofargs>
 		 *  - Push the original returnvalue on the stack
 		 *		pushl <poppedvalue>
 		 *  - And return to it.
 		 *		ret
 		 */

 		/* FIXME: The function stub is not reentrant. */

 		((LPBYTE)&(stub->popl))[0]	  = 0x8f;
 		((LPBYTE)&(stub->popl))[1]	  = 0x05;
 		stub->addr_popped = (DWORD)&(stub->oldret);
 		stub->pushl1	  = 0x68;
 		stub->newret	  = (DWORD)&(stub->addesp);
 		stub->pushl2	  = 0x68;
 		stub->origfun	  = (DWORD)fun;
 		stub->ret1	  = 0xc3;
 		((LPBYTE)&(stub->addesp))[0]=0x83;
 		((LPBYTE)&(stub->addesp))[1]=0xc4;
 		stub->nrofargs	  = nrofargs;
 		stub->pushl3	  = 0x68;
 			/* filled out by entrycode */
 		stub->oldret	  = 0xdeadbeef;
 		stub->ret2	  = 0xc3;
 		fun=(FARPROC)stub;
 	}
 	if (!fun) {
 		FIXME("function %s not found: %s\n",funcName,error);
 		return fun;
 	}
 	fun = SNOOP_GetProcAddress(wm->module,funcName,stub-first_stub,fun);
 	return (FARPROC)fun;
 }

 #else  /* HAVE_DL_API */

 WINE_MODREF *ELF_LoadLibraryExA( LPCSTR libname, DWORD flags)
 {
 	return NULL;
 }

 #endif  /* HAVE_DL_API */
	/*
	* UNIX dynamic loader
	*
	* Currently only supports stuff using the dl* API.
	*
	* Copyright 1998 Marcus Meissner
	*
	* FIXME: Small reentrancy problem.
	* IDEA(s): could be used to split up shell32,comctl32...
	*/

	#include "config.h"

	#include <assert.h>
	#include <stdio.h>
	#include <string.h>
	#include <sys/types.h>

	#include "snoop.h"
	#include "heap.h"
	#include "file.h"
	#include "module.h"
	#include "debugtools.h"
	#include "winerror.h"
	#include "wine/port.h"

	DEFAULT_DEBUG_CHANNEL(win32);

	#ifdef HAVE_DL_API

	typedef struct {
	WORD popl WINE_PACKED; /* 0x8f 0x05 */
	DWORD addr_popped WINE_PACKED;/* ... */
	BYTE pushl1 WINE_PACKED; /* 0x68 */
	DWORD newret WINE_PACKED; /* ... */
	BYTE pushl2 WINE_PACKED; /* 0x68 */
	DWORD origfun WINE_PACKED; /* original function */
	BYTE ret1 WINE_PACKED; /* 0xc3 */
	WORD addesp WINE_PACKED; /* 0x83 0xc4 */
	BYTE nrofargs WINE_PACKED; /* nr of arguments to add esp, */
	BYTE pushl3 WINE_PACKED; /* 0x68 */
	DWORD oldret WINE_PACKED; /* Filled out from popl above */
	BYTE ret2 WINE_PACKED; /* 0xc3 */
	} ELF_STDCALL_STUB;

	#define UNIX_DLL_ENDING "so"

	#define STUBSIZE 4095
	#define STUBOFFSET (sizeof(IMAGE_DOS_HEADER) + \
	sizeof(IMAGE_NT_HEADERS) + \
	sizeof(IMAGE_SECTION_HEADER))

	static FARPROC ELF_FindExportedFunction( WINE_MODREF *wm, LPCSTR funcName, BOOL snoop );

	static HMODULE ELF_CreateDummyModule( LPCSTR libname, LPCSTR modname )
	{
	PIMAGE_DOS_HEADER dh;
	PIMAGE_NT_HEADERS nth;
	PIMAGE_SECTION_HEADER sh;
	HMODULE hmod;

	hmod = (HMODULE)HeapAlloc( GetProcessHeap(), HEAP_ZERO_MEMORY,
	sizeof(IMAGE_DOS_HEADER) +
	sizeof(IMAGE_NT_HEADERS) +
	sizeof(IMAGE_SECTION_HEADER) + STUBSIZE );
	dh = (PIMAGE_DOS_HEADER)hmod;
	dh->e_magic = IMAGE_DOS_SIGNATURE;
	dh->e_lfanew = sizeof(IMAGE_DOS_HEADER);
	nth = PE_HEADER(hmod);
	nth->Signature = IMAGE_NT_SIGNATURE;
	nth->FileHeader.Machine = IMAGE_FILE_MACHINE_I386;
	nth->FileHeader.NumberOfSections = 1;
	nth->FileHeader.SizeOfOptionalHeader = sizeof(IMAGE_OPTIONAL_HEADER);
	nth->FileHeader.Characteristics =
	IMAGE_FILE_RELOCS_STRIPPED\|IMAGE_FILE_LINE_NUMS_STRIPPED\|
	IMAGE_FILE_LOCAL_SYMS_STRIPPED\|IMAGE_FILE_32BIT_MACHINE\|
	IMAGE_FILE_DLL\|IMAGE_FILE_DEBUG_STRIPPED;
	nth->OptionalHeader.Magic = IMAGE_NT_OPTIONAL_HDR_MAGIC;
	nth->OptionalHeader.SizeOfCode = 0;
	nth->OptionalHeader.SizeOfInitializedData = 0;
	nth->OptionalHeader.SizeOfUninitializedData = 0;
	nth->OptionalHeader.AddressOfEntryPoint = 0;
	nth->OptionalHeader.BaseOfCode = 0;
	nth->OptionalHeader.MajorOperatingSystemVersion = 4;
	nth->OptionalHeader.MajorImageVersion = 4;
	nth->OptionalHeader.SizeOfImage = 0;
	nth->OptionalHeader.SizeOfHeaders = 0;
	nth->OptionalHeader.Subsystem = IMAGE_SUBSYSTEM_NATIVE;
	nth->OptionalHeader.DllCharacteristics = 0;
	nth->OptionalHeader.NumberOfRvaAndSizes = 0;

	/* allocate one code section that crosses the whole process range
	* (we could find out from internal tables ... hmm )
	*/
	sh=(PIMAGE_SECTION_HEADER)(nth+1);
	strcpy(sh->Name,".text");
	sh->Misc.VirtualSize = STUBSIZE;
	sh->VirtualAddress = STUBOFFSET; /* so snoop can use it ... */
	sh->SizeOfRawData = STUBSIZE;
	sh->PointerToRawData = 0;
	sh->Characteristics = IMAGE_SCN_CNT_CODE\|IMAGE_SCN_CNT_INITIALIZED_DATA\|IMAGE_SCN_MEM_EXECUTE\|IMAGE_SCN_MEM_READ;
	return hmod;
	}

	WINE_MODREF *ELF_LoadLibraryExA( LPCSTR libname, DWORD flags)
	{
	WINE_MODREF *wm;
	HMODULE hmod;
	char modname,s,t,x;
	LPVOID *dlhandle;
	char error[256];

	t = HeapAlloc( GetProcessHeap(), HEAP_ZERO_MEMORY,
	strlen(libname) + strlen("lib.so") + 1 );
	*t = '\0';
	/* copy path to tempvar ... */
	s=strrchr(libname,'/');
	if (!s)
	s=strrchr(libname,'\\');
	if (s) {
	s++; /* skip / or \ */
	/* copy everything up to s-1 */
	memcpy(t,libname,s-libname);
	t[s-libname]= '\0';
	} else
	s = (LPSTR)libname;
	modname = s;
	/* append "lib" foo ".so" */
	strcat(t,"lib");
	x = t+strlen(t);
	strcat(t,s);
	s = strchr(x,'.');
	if (s) {
	while (s) {
	if (!FILE_strcasecmp(s,".dll")) {
	strcpy(s+1,UNIX_DLL_ENDING);
	break;
	}
	s=strchr(s+1,'.');
	}
	} else {
	strcat(x,"."UNIX_DLL_ENDING);
	}

	/* grab just the last piece of the path/filename
	which should be the name of the library we are
	looking to load. increment by 1 to skip the DOS slash */
	s = strrchr(t,'\\');
	s++;

	/* ... and open the library pointed by s, while t points
	points to the ENTIRE DOS filename of the library
	t is returned by HeapAlloc() above and so is also used
	with HeapFree() below */
	dlhandle = wine_dlopen(s,RTLD_NOW,error,sizeof(error));
	if (!dlhandle) {
	WARN("failed to load %s: %s\n", s, error);
	HeapFree( GetProcessHeap(), 0, t );
	SetLastError( ERROR_FILE_NOT_FOUND );
	return NULL;
	}

	hmod = ELF_CreateDummyModule( t, modname );

	SNOOP_RegisterDLL(hmod,libname,0,STUBSIZE/sizeof(ELF_STDCALL_STUB));

	wm = PE_CreateModule( hmod, libname, 0, 0, FALSE );
	wm->find_export = ELF_FindExportedFunction;
	wm->dlhandle = dlhandle;
	return wm;
	}

	static FARPROC ELF_FindExportedFunction( WINE_MODREF *wm, LPCSTR funcName, BOOL snoop )
	{
	LPVOID fun;
	int i,nrofargs = 0;
	ELF_STDCALL_STUB stub, first_stub;
	char error[256];

	if (!HIWORD(funcName)) {
	ERR("Can't import from UNIX dynamic libs by ordinal, sorry.\n");
	return (FARPROC)0;
	}
	fun = wine_dlsym(wm->dlhandle,funcName,error,sizeof(error));
	if (!fun)
	{
	/* we sometimes have an excess '_' at the beginning of the name */
	if (funcName[0]=='_')
	{
	funcName++ ;
	fun = wine_dlsym(wm->dlhandle,funcName,error,sizeof(error));
	}
	}
	if (!fun) {
	/* Function@nrofargs usually marks a stdcall function
	* with nrofargs bytes that are popped at the end
	*/
	if (strchr(funcName,'@')) {
	LPSTR t,fn = HEAP_strdupA( GetProcessHeap(), 0, funcName );

	t = strchr(fn,'@');
	*t = '\0';
	nrofargs = 0;
	sscanf(t+1,"%d",&nrofargs);
	fun = wine_dlsym(wm->dlhandle,fn,error,sizeof(error));
	HeapFree( GetProcessHeap(), 0, fn );
	}
	}
	/* We sometimes have Win32 dlls implemented using stdcall but UNIX
	* dlls using cdecl. If we find out the number of args the function
	* uses, we remove them from the stack using two small stubs.
	*/
	stub = first_stub = (ELF_STDCALL_STUB )((char )wm->module + STUBOFFSET);
	for (i=0;i<STUBSIZE/sizeof(ELF_STDCALL_STUB);i++) {
	if (!stub->origfun)
	break;
	if (stub->origfun == (DWORD)fun)
	break;
	stub++;
	}
	if (i==STUBSIZE/sizeof(ELF_STDCALL_STUB)) {
	ERR("please report, that there are not enough slots for stdcall stubs in the ELF loader.\n");
	assert(i<STUBSIZE/sizeof(ELF_STDCALL_STUB));
	}
	if (!stub->origfun)
	stub->origfun=(DWORD)fun; /* just a marker */

	if (fun && nrofargs) { /* we don't need it for 0 args */
	/* Selfmodifying entry/return stub for stdcall -> cdecl
	* conversion.
	* - Pop returnaddress directly into our return code
	* popl <into code below>
	* - Replace it by pointer to start of our returncode
	* push $newret
	* - And call the original function
	* jmp $orgfun
	* - Remove the arguments no longer needed
	* newret: add esp, <nrofargs>
	* - Push the original returnvalue on the stack
	* pushl <poppedvalue>
	* - And return to it.
	* ret
	*/

	/* FIXME: The function stub is not reentrant. */

	((LPBYTE)&(stub->popl))[0] = 0x8f;
	((LPBYTE)&(stub->popl))[1] = 0x05;
	stub->addr_popped = (DWORD)&(stub->oldret);
	stub->pushl1 = 0x68;
	stub->newret = (DWORD)&(stub->addesp);
	stub->pushl2 = 0x68;
	stub->origfun = (DWORD)fun;
	stub->ret1 = 0xc3;
	((LPBYTE)&(stub->addesp))[0]=0x83;
	((LPBYTE)&(stub->addesp))[1]=0xc4;
	stub->nrofargs = nrofargs;
	stub->pushl3 = 0x68;
	/* filled out by entrycode */
	stub->oldret = 0xdeadbeef;
	stub->ret2 = 0xc3;
	fun=(FARPROC)stub;
	}
	if (!fun) {
	FIXME("function %s not found: %s\n",funcName,error);
	return fun;
	}
	fun = SNOOP_GetProcAddress(wm->module,funcName,stub-first_stub,fun);
	return (FARPROC)fun;
	}

	#else /* HAVE_DL_API */

	WINE_MODREF *ELF_LoadLibraryExA( LPCSTR libname, DWORD flags)
	{
	return NULL;
	}

	#endif /* HAVE_DL_API */