Xash3D FWGS engine.

479 lines
14 KiB

/*
lib_custom_win.c - win32 custom dlls loader
Copyright (C) 2008 Uncle Mike
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
*/
#include "common.h"
#if XASH_LIB == LIB_WIN32 && XASH_X86
#include "lib_win.h"
#define NUMBER_OF_DIRECTORY_ENTRIES 16
#ifndef IMAGE_SIZEOF_BASE_RELOCATION
#define IMAGE_SIZEOF_BASE_RELOCATION ( sizeof( IMAGE_BASE_RELOCATION ))
#endif
typedef struct
{
PIMAGE_NT_HEADERS headers;
byte *codeBase;
void **modules;
int numModules;
int initialized;
} MEMORYMODULE, *PMEMORYMODULE;
// Protection flags for memory pages (Executable, Readable, Writeable)
static int ProtectionFlags[2][2][2] =
{
{
{ PAGE_NOACCESS, PAGE_WRITECOPY }, // not executable
{ PAGE_READONLY, PAGE_READWRITE },
},
{
{ PAGE_EXECUTE, PAGE_EXECUTE_WRITECOPY }, // executable
{ PAGE_EXECUTE_READ, PAGE_EXECUTE_READWRITE },
},
};
typedef BOOL (WINAPI *DllEntryProc)( HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpReserved );
#define GET_HEADER_DICTIONARY( module, idx ) &(module)->headers->OptionalHeader.DataDirectory[idx]
static void CopySections( const byte *data, PIMAGE_NT_HEADERS old_headers, PMEMORYMODULE module )
{
PIMAGE_SECTION_HEADER section = IMAGE_FIRST_SECTION( module->headers );
byte *codeBase = module->codeBase;
int i, size;
byte *dest;
for( i = 0; i < module->headers->FileHeader.NumberOfSections; i++, section++ )
{
if( section->SizeOfRawData == 0 )
{
// section doesn't contain data in the dll itself, but may define
// uninitialized data
size = old_headers->OptionalHeader.SectionAlignment;
if( size > 0 )
{
dest = (byte *)VirtualAlloc((byte *)CALCULATE_ADDRESS(codeBase, section->VirtualAddress), size, MEM_COMMIT, PAGE_READWRITE );
section->Misc.PhysicalAddress = (DWORD)dest;
memset( dest, 0, size );
}
// section is empty
continue;
}
// commit memory block and copy data from dll
dest = (byte *)VirtualAlloc((byte *)CALCULATE_ADDRESS(codeBase, section->VirtualAddress), section->SizeOfRawData, MEM_COMMIT, PAGE_READWRITE );
memcpy( dest, (byte *)CALCULATE_ADDRESS(data, section->PointerToRawData), section->SizeOfRawData );
section->Misc.PhysicalAddress = (DWORD)dest;
}
}
static void FreeSections( PIMAGE_NT_HEADERS old_headers, PMEMORYMODULE module )
{
PIMAGE_SECTION_HEADER section = IMAGE_FIRST_SECTION(module->headers);
byte *codeBase = module->codeBase;
int i, size;
for( i = 0; i < module->headers->FileHeader.NumberOfSections; i++, section++ )
{
if( section->SizeOfRawData == 0 )
{
size = old_headers->OptionalHeader.SectionAlignment;
if( size > 0 )
{
VirtualFree((byte *)CALCULATE_ADDRESS( codeBase, section->VirtualAddress ), size, MEM_DECOMMIT );
section->Misc.PhysicalAddress = 0;
}
continue;
}
VirtualFree((byte *)CALCULATE_ADDRESS( codeBase, section->VirtualAddress ), section->SizeOfRawData, MEM_DECOMMIT );
section->Misc.PhysicalAddress = 0;
}
}
static void FinalizeSections( MEMORYMODULE *module )
{
PIMAGE_SECTION_HEADER section = IMAGE_FIRST_SECTION( module->headers );
int i;
// loop through all sections and change access flags
for( i = 0; i < module->headers->FileHeader.NumberOfSections; i++, section++ )
{
DWORD protect, oldProtect, size;
int executable = (section->Characteristics & IMAGE_SCN_MEM_EXECUTE) != 0;
int readable = (section->Characteristics & IMAGE_SCN_MEM_READ) != 0;
int writeable = (section->Characteristics & IMAGE_SCN_MEM_WRITE) != 0;
if( section->Characteristics & IMAGE_SCN_MEM_DISCARDABLE )
{
// section is not needed any more and can safely be freed
VirtualFree((LPVOID)section->Misc.PhysicalAddress, section->SizeOfRawData, MEM_DECOMMIT);
continue;
}
// determine protection flags based on characteristics
protect = ProtectionFlags[executable][readable][writeable];
if( section->Characteristics & IMAGE_SCN_MEM_NOT_CACHED )
protect |= PAGE_NOCACHE;
// determine size of region
size = section->SizeOfRawData;
if( size == 0 )
{
if( section->Characteristics & IMAGE_SCN_CNT_INITIALIZED_DATA )
size = module->headers->OptionalHeader.SizeOfInitializedData;
else if( section->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA )
size = module->headers->OptionalHeader.SizeOfUninitializedData;
}
if( size > 0 )
{
// change memory access flags
if( !VirtualProtect((LPVOID)section->Misc.PhysicalAddress, size, protect, &oldProtect ))
Sys_Error( "error protecting memory page\n" );
}
}
}
static void PerformBaseRelocation( MEMORYMODULE *module, DWORD delta )
{
PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY( module, IMAGE_DIRECTORY_ENTRY_BASERELOC );
byte *codeBase = module->codeBase;
DWORD i;
if( directory->Size > 0 )
{
PIMAGE_BASE_RELOCATION relocation = (PIMAGE_BASE_RELOCATION)CALCULATE_ADDRESS( codeBase, directory->VirtualAddress );
for( ; relocation->VirtualAddress > 0; )
{
byte *dest = (byte *)CALCULATE_ADDRESS( codeBase, relocation->VirtualAddress );
word *relInfo = (word *)((byte *)relocation + IMAGE_SIZEOF_BASE_RELOCATION );
for( i = 0; i<((relocation->SizeOfBlock-IMAGE_SIZEOF_BASE_RELOCATION) / 2); i++, relInfo++ )
{
DWORD *patchAddrHL;
int type, offset;
// the upper 4 bits define the type of relocation
type = *relInfo >> 12;
// the lower 12 bits define the offset
offset = *relInfo & 0xfff;
switch( type )
{
case IMAGE_REL_BASED_ABSOLUTE:
// skip relocation
break;
case IMAGE_REL_BASED_HIGHLOW:
// change complete 32 bit address
patchAddrHL = (DWORD *)CALCULATE_ADDRESS( dest, offset );
*patchAddrHL += delta;
break;
default:
Con_Reportf( S_ERROR "PerformBaseRelocation: unknown relocation: %d\n", type );
break;
}
}
// advance to next relocation block
relocation = (PIMAGE_BASE_RELOCATION)CALCULATE_ADDRESS( relocation, relocation->SizeOfBlock );
}
}
}
FARPROC MemoryGetProcAddress( void *module, const char *name )
{
PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY((MEMORYMODULE *)module, IMAGE_DIRECTORY_ENTRY_EXPORT );
byte *codeBase = ((PMEMORYMODULE)module)->codeBase;
PIMAGE_EXPORT_DIRECTORY exports;
int idx = -1;
DWORD i, *nameRef;
WORD *ordinal;
if( directory->Size == 0 )
{
// no export table found
return NULL;
}
exports = (PIMAGE_EXPORT_DIRECTORY)CALCULATE_ADDRESS( codeBase, directory->VirtualAddress );
if( exports->NumberOfNames == 0 || exports->NumberOfFunctions == 0 )
{
// DLL doesn't export anything
return NULL;
}
// search function name in list of exported names
nameRef = (DWORD *)CALCULATE_ADDRESS( codeBase, exports->AddressOfNames );
ordinal = (WORD *)CALCULATE_ADDRESS( codeBase, exports->AddressOfNameOrdinals );
for( i = 0; i < exports->NumberOfNames; i++, nameRef++, ordinal++ )
{
// GetProcAddress case insensative ?????
if( !Q_stricmp( name, (const char *)CALCULATE_ADDRESS( codeBase, *nameRef )))
{
idx = *ordinal;
break;
}
}
if( idx == -1 )
{
// exported symbol not found
return NULL;
}
if((DWORD)idx > exports->NumberOfFunctions )
{
// name <-> ordinal number don't match
return NULL;
}
// addressOfFunctions contains the RVAs to the "real" functions
return (FARPROC)CALCULATE_ADDRESS( codeBase, *(DWORD *)CALCULATE_ADDRESS( codeBase, exports->AddressOfFunctions + (idx * 4)));
}
static int BuildImportTable( MEMORYMODULE *module )
{
PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY( module, IMAGE_DIRECTORY_ENTRY_IMPORT );
byte *codeBase = module->codeBase;
int result = 1;
if( directory->Size > 0 )
{
PIMAGE_IMPORT_DESCRIPTOR importDesc = (PIMAGE_IMPORT_DESCRIPTOR)CALCULATE_ADDRESS( codeBase, directory->VirtualAddress );
for( ; !IsBadReadPtr( importDesc, sizeof( IMAGE_IMPORT_DESCRIPTOR )) && importDesc->Name; importDesc++ )
{
DWORD *thunkRef, *funcRef;
LPCSTR libname;
void *handle;
libname = (LPCSTR)CALCULATE_ADDRESS( codeBase, importDesc->Name );
handle = COM_LoadLibrary( libname, false, true );
if( handle == NULL )
{
Con_Printf( S_ERROR "couldn't load library %s\n", libname );
result = 0;
break;
}
module->modules = (void *)Mem_Realloc( host.mempool, module->modules, (module->numModules + 1) * (sizeof( void* )));
module->modules[module->numModules++] = handle;
if( importDesc->OriginalFirstThunk )
{
thunkRef = (DWORD *)CALCULATE_ADDRESS( codeBase, importDesc->OriginalFirstThunk );
funcRef = (DWORD *)CALCULATE_ADDRESS( codeBase, importDesc->FirstThunk );
}
else
{
// no hint table
thunkRef = (DWORD *)CALCULATE_ADDRESS( codeBase, importDesc->FirstThunk );
funcRef = (DWORD *)CALCULATE_ADDRESS( codeBase, importDesc->FirstThunk );
}
for( ; *thunkRef; thunkRef++, funcRef++ )
{
LPCSTR funcName;
if( IMAGE_SNAP_BY_ORDINAL( *thunkRef ))
{
funcName = (LPCSTR)IMAGE_ORDINAL( *thunkRef );
*funcRef = (DWORD)COM_GetProcAddress( handle, funcName );
}
else
{
PIMAGE_IMPORT_BY_NAME thunkData = (PIMAGE_IMPORT_BY_NAME)CALCULATE_ADDRESS( codeBase, *thunkRef );
funcName = (LPCSTR)&thunkData->Name;
*funcRef = (DWORD)COM_GetProcAddress( handle, funcName );
}
if( *funcRef == 0 )
{
Con_Printf( S_ERROR "%s unable to find address: %s\n", libname, funcName );
result = 0;
break;
}
}
if( !result ) break;
}
}
return result;
}
void MemoryFreeLibrary( void *hInstance )
{
MEMORYMODULE *module = (MEMORYMODULE *)hInstance;
if( module != NULL )
{
int i;
if( module->initialized != 0 )
{
// notify library about detaching from process
DllEntryProc DllEntry = (DllEntryProc)CALCULATE_ADDRESS( module->codeBase, module->headers->OptionalHeader.AddressOfEntryPoint );
(*DllEntry)((HINSTANCE)module->codeBase, DLL_PROCESS_DETACH, 0 );
module->initialized = 0;
}
if( module->modules != NULL )
{
// free previously opened libraries
for( i = 0; i < module->numModules; i++ )
{
if( module->modules[i] != NULL )
COM_FreeLibrary( module->modules[i] );
}
Mem_Free( module->modules ); // Mem_Realloc end
}
FreeSections( module->headers, module );
if( module->codeBase != NULL )
{
// release memory of library
VirtualFree( module->codeBase, 0, MEM_RELEASE );
}
HeapFree( GetProcessHeap(), 0, module );
}
}
void *MemoryLoadLibrary( const char *name )
{
MEMORYMODULE *result = NULL;
PIMAGE_DOS_HEADER dos_header;
PIMAGE_NT_HEADERS old_header;
byte *code, *headers;
DWORD locationDelta;
DllEntryProc DllEntry;
string errorstring;
qboolean successfull;
void *data = NULL;
data = FS_LoadFile( name, NULL, false );
if( !data )
{
Q_snprintf( errorstring, sizeof( errorstring ), "couldn't load %s", name );
goto library_error;
}
dos_header = (PIMAGE_DOS_HEADER)data;
if( dos_header->e_magic != IMAGE_DOS_SIGNATURE )
{
Q_snprintf( errorstring, sizeof( errorstring ), "%s it's not a valid executable file", name );
goto library_error;
}
old_header = (PIMAGE_NT_HEADERS)&((const byte *)(data))[dos_header->e_lfanew];
if( old_header->Signature != IMAGE_NT_SIGNATURE )
{
Q_snprintf( errorstring, sizeof( errorstring ), "%s missing PE header", name );
goto library_error;
}
// reserve memory for image of library
code = (byte *)VirtualAlloc((LPVOID)(old_header->OptionalHeader.ImageBase), old_header->OptionalHeader.SizeOfImage, MEM_RESERVE, PAGE_READWRITE );
if( code == NULL )
{
// try to allocate memory at arbitrary position
code = (byte *)VirtualAlloc( NULL, old_header->OptionalHeader.SizeOfImage, MEM_RESERVE, PAGE_READWRITE );
}
if( code == NULL )
{
Q_snprintf( errorstring, sizeof( errorstring ), "%s can't reserve memory", name );
goto library_error;
}
result = (MEMORYMODULE *)HeapAlloc( GetProcessHeap(), 0, sizeof( MEMORYMODULE ));
result->codeBase = code;
result->numModules = 0;
result->modules = NULL;
result->initialized = 0;
// XXX: is it correct to commit the complete memory region at once?
// calling DllEntry raises an exception if we don't...
VirtualAlloc( code, old_header->OptionalHeader.SizeOfImage, MEM_COMMIT, PAGE_READWRITE );
// commit memory for headers
headers = (byte *)VirtualAlloc( code, old_header->OptionalHeader.SizeOfHeaders, MEM_COMMIT, PAGE_READWRITE );
// copy PE header to code
memcpy( headers, dos_header, dos_header->e_lfanew + old_header->OptionalHeader.SizeOfHeaders );
result->headers = (PIMAGE_NT_HEADERS)&((const byte *)(headers))[dos_header->e_lfanew];
// update position
result->headers->OptionalHeader.ImageBase = (DWORD)code;
// copy sections from DLL file block to new memory location
CopySections( data, old_header, result );
// adjust base address of imported data
locationDelta = (DWORD)(code - old_header->OptionalHeader.ImageBase);
if( locationDelta != 0 ) PerformBaseRelocation( result, locationDelta );
// load required dlls and adjust function table of imports
if( !BuildImportTable( result ))
{
Q_snprintf( errorstring, sizeof( errorstring ), "%s failed to build import table", name );
goto library_error;
}
// mark memory pages depending on section headers and release
// sections that are marked as "discardable"
FinalizeSections( result );
// get entry point of loaded library
if( result->headers->OptionalHeader.AddressOfEntryPoint != 0 )
{
DllEntry = (DllEntryProc)CALCULATE_ADDRESS( code, result->headers->OptionalHeader.AddressOfEntryPoint );
if( DllEntry == 0 )
{
Q_snprintf( errorstring, sizeof( errorstring ), "%s has no entry point", name );
goto library_error;
}
// notify library about attaching to process
successfull = (*DllEntry)((HINSTANCE)code, DLL_PROCESS_ATTACH, 0 );
if( !successfull )
{
Q_snprintf( errorstring, sizeof( errorstring ), "can't attach library %s", name );
goto library_error;
}
result->initialized = 1;
}
Mem_Free( data ); // release memory
return (void *)result;
library_error:
// cleanup
if( data ) Mem_Free( data );
MemoryFreeLibrary( result );
Con_Printf( S_ERROR "LoadLibrary: %s\n", errorstring );
return NULL;
}
#endif // XASH_LIB == LIB_WIN32 && XASH_X86