library/loader.c

   1 /*
   2  * Win32 builtin dlls support
   3  *
   4  * Copyright 2000 Alexandre Julliard
   5  */
   6
   7 #include "config.h"
   8
   9 #include <assert.h>
  10 #include <ctype.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/types.h>
  14 #include <unistd.h>
  15 #ifdef HAVE_SYS_MMAN_H
  16 #include <sys/mman.h>
  17 #endif
  18 #ifdef HAVE_DL_API
  19 #include <dlfcn.h>
  20 #endif
  21
  22 #include "winnt.h"
  23 #include "wine/library.h"
  24 #include "wine/port.h"
  25
  26 #define MAX_DLLS 100
  27
  28 static struct
  29 {
  30     const IMAGE_NT_HEADERS *nt;           /* NT header */
  31     const char             *filename;     /* DLL file name */
  32 } builtin_dlls[MAX_DLLS];
  33
  34 static int nb_dlls;
  35
  36 static const IMAGE_NT_HEADERS *main_exe;
  37
  38 static load_dll_callback_t load_dll_callback;
  39
  40 static char **dll_paths;
  41 static int nb_dll_paths;
  42 static int dll_path_maxlen;
  43 static int init_done;
  44
  45
  46 /* build the dll load path from the WINEDLLPATH variable */
  47 static void build_dll_path(void)
  48 {
  49     int count = 0;
  50     char *p, *path = getenv( "WINEDLLPATH" );
  51
  52     init_done = 1;
  53     if (!path) return;
  54     path = strdup(path);
  55     p = path;
  56     while (*p)
  57     {
  58         while (*p == ':') p++;
  59         if (!*p) break;
  60         count++;
  61         while (*p && *p != ':') p++;
  62     }
  63
  64     dll_paths = malloc( count * sizeof(*dll_paths) );
  65     p = path;
  66     nb_dll_paths = 0;
  67     while (*p)
  68     {
  69         while (*p == ':') *p++ = 0;
  70         if (!*p) break;
  71         dll_paths[nb_dll_paths] = p;
  72         while (*p && *p != ':') p++;
  73         if (p - dll_paths[nb_dll_paths] > dll_path_maxlen)
  74             dll_path_maxlen = p - dll_paths[nb_dll_paths];
  75         nb_dll_paths++;
  76     }
  77 }
  78
  79
  80 /* open a library for a given dll, searching in the dll path
  81  * 'name' must be the Windows dll name (e.g. "kernel32.dll") */
  82 static void *dlopen_dll( const char *name )
  83 {
  84 #ifdef HAVE_DL_API
  85     int i, namelen = strlen(name);
  86     char *buffer, *p;
  87     void *ret = NULL;
  88
  89     if (!init_done) build_dll_path();
  90
  91     /* check for .dll or .exe extension to remove */
  92     if ((p = strrchr( name, '.' )))
  93     {
  94         if (!strcasecmp( p, ".dll" ) || !strcasecmp( p, ".exe" )) namelen -= 4;
  95     }
  96
  97     buffer = malloc( dll_path_maxlen + namelen + 8 );
  98
  99     /* store the name at the end of the buffer, prefixed by /lib and followed by .so */
 100     p = buffer + dll_path_maxlen;
 101     memcpy( p, "/lib", 4 );
 102     for (i = 0, p += 4; i < namelen; i++, p++) *p = tolower(name[i]);
 103     memcpy( p, ".so", 4 );
 104
 105     for (i = 0; i < nb_dll_paths; i++)
 106     {
 107         int len = strlen(dll_paths[i]);
 108         char *p = buffer + dll_path_maxlen - len;
 109         memcpy( p, dll_paths[i], len );
 110         if ((ret = dlopen( p, RTLD_NOW ))) break;
 111     }
 112
 113     /* now try the default dlopen search path */
 114     if (!ret) ret = dlopen( buffer + dll_path_maxlen + 1, RTLD_NOW );
 115     free( buffer );
 116     return ret;
 117 #else
 118     return NULL;
 119 #endif
 120 }
 121
 122
 123 /* adjust an array of pointers to make them into RVAs */
 124 static inline void fixup_rva_ptrs( void *array, void *base, int count )
 125 {
 126     void **ptr = (void **)array;
 127     while (count--)
 128     {
 129         if (*ptr) *ptr = (void *)((char *)*ptr - (char *)base);
 130         ptr++;
 131     }
 132 }
 133
 134
 135 /* fixup RVAs in the resource directory */
 136 static void fixup_resources( IMAGE_RESOURCE_DIRECTORY *dir, char *root, void *base )
 137 {
 138     IMAGE_RESOURCE_DIRECTORY_ENTRY *entry;
 139     int i;
 140
 141     entry = (IMAGE_RESOURCE_DIRECTORY_ENTRY *)(dir + 1);
 142     for (i = 0; i < dir->NumberOfNamedEntries + dir->NumberOfIdEntries; i++, entry++)
 143     {
 144         void *ptr = root + entry->u2.s.OffsetToDirectory;
 145         if (entry->u2.s.DataIsDirectory) fixup_resources( ptr, root, base );
 146         else
 147         {
 148             IMAGE_RESOURCE_DATA_ENTRY *data = ptr;
 149             fixup_rva_ptrs( &data->OffsetToData, base, 1 );
 150         }
 151     }
 152 }
 153
 154
 155 /* map a builtin dll in memory and fixup RVAs */
 156 static void *map_dll( const IMAGE_NT_HEADERS *nt_descr )
 157 {
 158     IMAGE_DATA_DIRECTORY *dir;
 159     IMAGE_DOS_HEADER *dos;
 160     IMAGE_NT_HEADERS *nt;
 161     IMAGE_SECTION_HEADER *sec;
 162     BYTE *addr, *code_start, *data_start;
 163     size_t page_size = getpagesize();
 164     int nb_sections = 2;  /* code + data */
 165
 166     size_t size = (sizeof(IMAGE_DOS_HEADER)
 167                    + sizeof(IMAGE_NT_HEADERS)
 168                    + nb_sections * sizeof(IMAGE_SECTION_HEADER));
 169
 170     assert( size <= page_size );
 171
 172     if (nt_descr->OptionalHeader.ImageBase)
 173     {
 174         addr = wine_anon_mmap( (void *)nt_descr->OptionalHeader.ImageBase,
 175                                page_size, PROT_READ|PROT_WRITE, MAP_FIXED );
 176         if (addr != (BYTE *)nt_descr->OptionalHeader.ImageBase) return NULL;
 177     }
 178     else
 179     {
 180         /* this will leak memory; but it should never happen */
 181         addr = wine_anon_mmap( NULL, page_size, PROT_READ|PROT_WRITE, 0 );
 182         if (addr == (BYTE *)-1) return NULL;
 183     }
 184
 185     dos    = (IMAGE_DOS_HEADER *)addr;
 186     nt     = (IMAGE_NT_HEADERS *)(dos + 1);
 187     sec    = (IMAGE_SECTION_HEADER *)(nt + 1);
 188     code_start = addr + page_size;
 189
 190     /* HACK! */
 191     data_start = code_start + page_size;
 192
 193     /* Build the DOS and NT headers */
 194
 195     dos->e_magic  = IMAGE_DOS_SIGNATURE;
 196     dos->e_lfanew = sizeof(*dos);
 197
 198     *nt = *nt_descr;
 199
 200     nt->FileHeader.NumberOfSections                = nb_sections;
 201     nt->OptionalHeader.SizeOfCode                  = data_start - code_start;
 202     nt->OptionalHeader.SizeOfInitializedData       = 0;
 203     nt->OptionalHeader.SizeOfUninitializedData     = 0;
 204     nt->OptionalHeader.ImageBase                   = (DWORD)addr;
 205
 206     fixup_rva_ptrs( &nt->OptionalHeader.AddressOfEntryPoint, addr, 1 );
 207
 208     /* Build the code section */
 209
 210     strcpy( sec->Name, ".text" );
 211     sec->SizeOfRawData = data_start - code_start;
 212     sec->Misc.VirtualSize = sec->SizeOfRawData;
 213     sec->VirtualAddress   = code_start - addr;
 214     sec->PointerToRawData = code_start - addr;
 215     sec->Characteristics  = (IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ);
 216     sec++;
 217
 218     /* Build the data section */
 219
 220     strcpy( sec->Name, ".data" );
 221     sec->SizeOfRawData = 0;
 222     sec->Misc.VirtualSize = sec->SizeOfRawData;
 223     sec->VirtualAddress   = data_start - addr;
 224     sec->PointerToRawData = data_start - addr;
 225     sec->Characteristics  = (IMAGE_SCN_CNT_INITIALIZED_DATA |
 226                              IMAGE_SCN_MEM_WRITE | IMAGE_SCN_MEM_READ);
 227     sec++;
 228
 229     /* Build the import directory */
 230
 231     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_IMPORT_DIRECTORY];
 232     if (dir->Size)
 233     {
 234         IMAGE_IMPORT_DESCRIPTOR *imports = (void *)dir->VirtualAddress;
 235         fixup_rva_ptrs( &dir->VirtualAddress, addr, 1 );
 236         /* we can fixup everything at once since we only have pointers and 0 values */
 237         fixup_rva_ptrs( imports, addr, dir->Size / sizeof(void*) );
 238     }
 239
 240     /* Build the resource directory */
 241
 242     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_RESOURCE_DIRECTORY];
 243     if (dir->Size)
 244     {
 245         void *ptr = (void *)dir->VirtualAddress;
 246         fixup_rva_ptrs( &dir->VirtualAddress, addr, 1 );
 247         fixup_resources( ptr, ptr, addr );
 248     }
 249
 250     /* Build the export directory */
 251
 252     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_EXPORT_DIRECTORY];
 253     if (dir->Size)
 254     {
 255         IMAGE_EXPORT_DIRECTORY *exports = (void *)dir->VirtualAddress;
 256         fixup_rva_ptrs( &dir->VirtualAddress, addr, 1 );
 257         fixup_rva_ptrs( (void *)exports->AddressOfFunctions, addr, exports->NumberOfFunctions );
 258         fixup_rva_ptrs( (void *)exports->AddressOfNames, addr, exports->NumberOfNames );
 259         fixup_rva_ptrs( &exports->Name, addr, 1 );
 260         fixup_rva_ptrs( &exports->AddressOfFunctions, addr, 1 );
 261         fixup_rva_ptrs( &exports->AddressOfNames, addr, 1 );
 262         fixup_rva_ptrs( &exports->AddressOfNameOrdinals, addr, 1 );
 263     }
 264     return addr;
 265 }
 266
 267
 268 /***********************************************************************
 269  *           __wine_dll_register
 270  *
 271  * Register a built-in DLL descriptor.
 272  */
 273 void __wine_dll_register( const IMAGE_NT_HEADERS *header, const char *filename )
 274 {
 275     if (load_dll_callback) load_dll_callback( map_dll(header), filename );
 276     else
 277     {
 278         if (!(header->FileHeader.Characteristics & IMAGE_FILE_DLL))
 279             main_exe = header;
 280         else
 281         {
 282             assert( nb_dlls < MAX_DLLS );
 283             builtin_dlls[nb_dlls].nt = header;
 284             builtin_dlls[nb_dlls].filename = filename;
 285             nb_dlls++;
 286         }
 287     }
 288 }
 289
 290
 291 /***********************************************************************
 292  *           wine_dll_set_callback
 293  *
 294  * Set the callback function for dll loading, and call it
 295  * for all dlls that were implicitly loaded already.
 296  */
 297 void wine_dll_set_callback( load_dll_callback_t load )
 298 {
 299     int i;
 300     load_dll_callback = load;
 301     for (i = 0; i < nb_dlls; i++)
 302     {
 303         const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 304         if (!nt) continue;
 305         builtin_dlls[i].nt = NULL;
 306         load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 307     }
 308     nb_dlls = 0;
 309     if (main_exe) load_dll_callback( map_dll(main_exe), "" );
 310 }
 311
 312
 313 /***********************************************************************
 314  *           wine_dll_load
 315  *
 316  * Load a builtin dll.
 317  */
 318 void *wine_dll_load( const char *filename )
 319 {
 320     int i;
 321
 322     /* callback must have been set already */
 323     assert( load_dll_callback );
 324
 325     /* check if we have it in the list */
 326     /* this can happen when initializing pre-loaded dlls in wine_dll_set_callback */
 327     for (i = 0; i < nb_dlls; i++)
 328     {
 329         if (!builtin_dlls[i].nt) continue;
 330         if (!strcasecmp( builtin_dlls[i].filename, filename ))
 331         {
 332             const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 333             builtin_dlls[i].nt = NULL;
 334             load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 335             return (void *)1;
 336         }
 337     }
 338     return dlopen_dll( filename );
 339 }
 340
 341
 342 /***********************************************************************
 343  *           wine_dll_unload
 344  *
 345  * Unload a builtin dll.
 346  */
 347 void wine_dll_unload( void *handle )
 348 {
 349 #ifdef HAVE_DL_API
 350     if (handle != (void *)1) dlclose( handle );
 351 #endif
 352 }