2 * Creation of Wine fake dlls for apps that access the dll file directly.
4 * Copyright 2006 Alexandre Julliard
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.
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.
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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
23 #define NONAMELESSSTRUCT
24 #define NONAMELESSUNION
26 #define WIN32_NO_STATUS
33 #include "wine/unicode.h"
34 #include "wine/debug.h"
36 WINE_DEFAULT_DEBUG_CHANNEL(setupapi);
38 static const char fakedll_signature[] = "Wine placeholder DLL";
40 static const unsigned int file_alignment = 512;
41 static const unsigned int section_alignment = 4096;
51 #define ALIGN(size,align) (((size) + (align) - 1) & ~((align) - 1))
53 /* contents of the dll sections */
55 static const BYTE dll_code_section[] = { 0x31, 0xc0, /* xor %eax,%eax */
56 0xc2, 0x0c, 0x00 }; /* ret $12 */
58 static const BYTE exe_code_section[] = { 0xb8, 0x01, 0x00, 0x00, 0x00, /* movl $1,%eax */
59 0xc2, 0x04, 0x00 }; /* ret $4 */
61 static const IMAGE_BASE_RELOCATION reloc_section; /* empty relocs */
64 /* wrapper for WriteFile */
65 static inline BOOL xwrite( struct dll_info *info, const void *data, DWORD size, DWORD offset )
69 return (SetFilePointer( info->handle, offset, NULL, FILE_BEGIN ) != INVALID_SET_FILE_POINTER &&
70 WriteFile( info->handle, data, size, &res, NULL ) &&
74 /* add a new section to the dll NT header */
75 static void add_section( struct dll_info *info, const char *name, DWORD size, DWORD flags )
77 IMAGE_SECTION_HEADER *sec = (IMAGE_SECTION_HEADER *)(info->nt + 1);
79 sec += info->nt->FileHeader.NumberOfSections;
80 memcpy( (char *)sec->Name, name, min( strlen(name), sizeof(sec->Name)) );
81 sec->Misc.VirtualSize = ALIGN( size, section_alignment );
82 sec->VirtualAddress = info->mem_pos;
83 sec->SizeOfRawData = size;
84 sec->PointerToRawData = info->file_pos;
85 sec->Characteristics = flags;
86 info->file_pos += ALIGN( size, file_alignment );
87 info->mem_pos += ALIGN( size, section_alignment );
88 info->nt->FileHeader.NumberOfSections++;
91 /* add a data directory to the dll NT header */
92 static inline void add_directory( struct dll_info *info, unsigned int idx, DWORD rva, DWORD size )
94 info->nt->OptionalHeader.DataDirectory[idx].VirtualAddress = rva;
95 info->nt->OptionalHeader.DataDirectory[idx].Size = size;
98 /* find the limits of the resource data */
99 static void get_resource_data( const IMAGE_RESOURCE_DIRECTORY *dir, const BYTE *root,
100 DWORD *rva_start, DWORD *rva_end )
102 const IMAGE_RESOURCE_DIRECTORY_ENTRY *entry;
105 entry = (const IMAGE_RESOURCE_DIRECTORY_ENTRY *)(dir + 1);
106 for (i = 0; i < dir->NumberOfNamedEntries + dir->NumberOfIdEntries; i++, entry++)
108 const void *ptr = root + entry->u2.s3.OffsetToDirectory;
109 if (entry->u2.s3.DataIsDirectory) get_resource_data( ptr, root, rva_start, rva_end );
112 const IMAGE_RESOURCE_DATA_ENTRY *data = ptr;
113 *rva_start = min( *rva_start, data->OffsetToData );
114 *rva_end = max( *rva_end, data->OffsetToData + data->Size );
119 /* fixup RVAs of resource data */
120 static void fixup_resources( IMAGE_RESOURCE_DIRECTORY *dir, BYTE *root, int delta )
122 IMAGE_RESOURCE_DIRECTORY_ENTRY *entry;
125 entry = (IMAGE_RESOURCE_DIRECTORY_ENTRY *)(dir + 1);
126 for (i = 0; i < dir->NumberOfNamedEntries + dir->NumberOfIdEntries; i++, entry++)
128 void *ptr = root + entry->u2.s3.OffsetToDirectory;
129 if (entry->u2.s3.DataIsDirectory) fixup_resources( ptr, root, delta );
132 IMAGE_RESOURCE_DATA_ENTRY *data = ptr;
133 if (data->OffsetToData) data->OffsetToData += delta;
138 /* add version resources to the dll by copying them from the source module */
139 static BOOL add_version_resource( HMODULE module, struct dll_info *dll_info )
142 DWORD rva_start = ~0U, rva_end = 0, dir_size, total_size;
143 const IMAGE_RESOURCE_DIRECTORY *basedir;
144 const BYTE *data_start, *root;
147 if (!module) return TRUE;
148 if (LdrFindResourceDirectory_U( module, NULL, 0, &basedir ) != STATUS_SUCCESS) return TRUE;
149 root = (const BYTE *)basedir;
150 get_resource_data( basedir, root, &rva_start, &rva_end );
151 data_start = (const BYTE *)module + rva_start;
152 if (data_start <= root) return FALSE;
153 dir_size = data_start - root;
154 if (!(buffer = HeapAlloc( GetProcessHeap(), 0, dir_size ))) return FALSE;
155 memcpy( buffer, root, dir_size );
156 fixup_resources( (IMAGE_RESOURCE_DIRECTORY *)buffer, buffer, dll_info->mem_pos + dir_size - rva_start );
157 if (!xwrite( dll_info, buffer, dir_size, dll_info->file_pos )) goto done;
158 if (!xwrite( dll_info, data_start, rva_end - rva_start, dll_info->file_pos + dir_size )) goto done;
159 total_size = dir_size + rva_end - rva_start;
160 add_directory( dll_info, IMAGE_DIRECTORY_ENTRY_RESOURCE, dll_info->mem_pos, total_size );
161 add_section( dll_info, ".rsrc", total_size, IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ );
164 HeapFree( GetProcessHeap(), 0, buffer );
168 /* build a complete fake dll, optionally using module as a source */
169 static BOOL build_fake_dll( HANDLE file, HMODULE module )
171 IMAGE_DOS_HEADER *dos;
172 IMAGE_NT_HEADERS *nt;
173 const IMAGE_NT_HEADERS *src_nt = NULL;
174 struct dll_info info;
177 DWORD lfanew = (sizeof(*dos) + sizeof(fakedll_signature) + 15) & ~15;
178 DWORD size, header_size = lfanew + sizeof(*nt);
181 buffer = HeapAlloc( GetProcessHeap(), HEAP_ZERO_MEMORY, header_size + 8 * sizeof(IMAGE_SECTION_HEADER) );
183 dos = (IMAGE_DOS_HEADER *)buffer;
184 dos->e_magic = IMAGE_DOS_SIGNATURE;
185 dos->e_cblp = sizeof(*dos);
187 dos->e_cparhdr = lfanew / 16;
189 dos->e_maxalloc = 0xffff;
192 dos->e_lfarlc = lfanew;
193 dos->e_lfanew = lfanew;
194 memcpy( dos + 1, fakedll_signature, sizeof(fakedll_signature) );
196 nt = info.nt = (IMAGE_NT_HEADERS *)(buffer + lfanew);
197 src_nt = RtlImageNtHeader( module );
198 /* some fields are copied from the source dll */
199 #define SET(field,def) nt->field = src_nt ? src_nt->field : def
200 SET( FileHeader.Machine, IMAGE_FILE_MACHINE_I386 );
201 SET( FileHeader.TimeDateStamp, 0 );
202 SET( FileHeader.Characteristics, IMAGE_FILE_DLL );
203 SET( OptionalHeader.MajorLinkerVersion, 1 );
204 SET( OptionalHeader.MinorLinkerVersion, 0 );
205 SET( OptionalHeader.MajorOperatingSystemVersion, 1 );
206 SET( OptionalHeader.MinorOperatingSystemVersion, 0 );
207 SET( OptionalHeader.MajorImageVersion, 1 );
208 SET( OptionalHeader.MinorImageVersion, 0 );
209 SET( OptionalHeader.MajorSubsystemVersion, 4 );
210 SET( OptionalHeader.MinorSubsystemVersion, 0 );
211 SET( OptionalHeader.Win32VersionValue, 0 );
212 SET( OptionalHeader.Subsystem, IMAGE_SUBSYSTEM_WINDOWS_GUI );
213 SET( OptionalHeader.DllCharacteristics, 0 );
214 SET( OptionalHeader.SizeOfStackReserve, 0 );
215 SET( OptionalHeader.SizeOfStackCommit, 0 );
216 SET( OptionalHeader.SizeOfHeapReserve, 0 );
217 SET( OptionalHeader.SizeOfHeapCommit, 0 );
219 /* other fields have fixed values */
220 nt->Signature = IMAGE_NT_SIGNATURE;
221 nt->FileHeader.NumberOfSections = 0;
222 nt->FileHeader.SizeOfOptionalHeader = IMAGE_SIZEOF_NT_OPTIONAL_HEADER;
223 nt->OptionalHeader.Magic = IMAGE_NT_OPTIONAL_HDR_MAGIC;
224 nt->OptionalHeader.ImageBase = 0x10000000;
225 nt->OptionalHeader.SectionAlignment = section_alignment;
226 nt->OptionalHeader.FileAlignment = file_alignment;
227 nt->OptionalHeader.NumberOfRvaAndSizes = IMAGE_NUMBEROF_DIRECTORY_ENTRIES;
229 header_size = (BYTE *)(nt + 1) - buffer;
230 info.mem_pos = ALIGN( header_size, section_alignment );
231 info.file_pos = ALIGN( header_size, file_alignment );
233 nt->OptionalHeader.AddressOfEntryPoint = info.mem_pos;
234 nt->OptionalHeader.BaseOfCode = info.mem_pos;
236 if (nt->FileHeader.Characteristics & IMAGE_FILE_DLL)
238 size = sizeof(dll_code_section);
239 if (!xwrite( &info, dll_code_section, size, info.file_pos )) goto done;
243 size = sizeof(exe_code_section);
244 if (!xwrite( &info, exe_code_section, size, info.file_pos )) goto done;
246 nt->OptionalHeader.SizeOfCode = size;
247 add_section( &info, ".text", size, IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ );
249 if (!xwrite( &info, &reloc_section, sizeof(reloc_section), info.file_pos )) goto done;
250 add_directory( &info, IMAGE_DIRECTORY_ENTRY_BASERELOC, info.mem_pos, sizeof(reloc_section) );
251 add_section( &info, ".reloc", sizeof(reloc_section),
252 IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_DISCARDABLE | IMAGE_SCN_MEM_READ );
254 if (!add_version_resource( module, &info )) goto done;
256 header_size += nt->FileHeader.NumberOfSections * sizeof(IMAGE_SECTION_HEADER);
257 nt->OptionalHeader.SizeOfHeaders = ALIGN( header_size, file_alignment );
258 nt->OptionalHeader.SizeOfImage = ALIGN( info.mem_pos, section_alignment );
259 ret = xwrite( &info, buffer, header_size, 0 );
261 HeapFree( GetProcessHeap(), 0, buffer );
265 /* check if an existing file is a fake dll so that we can overwrite it */
266 static BOOL is_fake_dll( HANDLE h )
268 IMAGE_DOS_HEADER *dos;
270 BYTE buffer[sizeof(*dos) + sizeof(fakedll_signature)];
272 if (!ReadFile( h, buffer, sizeof(buffer), &size, NULL ) || size != sizeof(buffer))
274 dos = (IMAGE_DOS_HEADER *)buffer;
275 if (dos->e_magic != IMAGE_DOS_SIGNATURE) return FALSE;
276 if (dos->e_lfanew < size) return FALSE;
277 return !memcmp( dos + 1, fakedll_signature, sizeof(fakedll_signature) );
280 /***********************************************************************
283 BOOL create_fake_dll( const WCHAR *name, const WCHAR *source )
289 /* first check for an existing file */
290 h = CreateFileW( name, GENERIC_READ|GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL );
291 if (h != INVALID_HANDLE_VALUE)
293 if (!is_fake_dll( h ))
295 TRACE( "%s is not a fake dll, not overwriting it\n", debugstr_w(name) );
299 /* truncate the file */
300 SetFilePointer( h, 0, NULL, FILE_BEGIN );
305 h = CreateFileW( name, GENERIC_WRITE, 0, NULL, CREATE_NEW, 0, NULL );
306 if (h == INVALID_HANDLE_VALUE)
308 WARN( "failed to create %s\n", debugstr_w(name) );
313 module = LoadLibraryW( source );
315 ret = build_fake_dll( h, module );
318 if (module) FreeLibrary( module );
319 if (!ret) DeleteFileW( name );