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   1 /*
   2  * win32_apply.c - Windows-specific code for applying files from a WIM image.
   3  */
   4
   5 /*
   6  * Copyright (C) 2013 Eric Biggers
   7  *
   8  * This file is part of wimlib, a library for working with WIM files.
   9  *
  10  * wimlib is free software; you can redistribute it and/or modify it under the
  11  * terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 3 of the License, or (at your option)
  13  * any later version.
  14  *
  15  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  16  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  17  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  22  */
  23
  24 #ifdef __WIN32__
  25
  26 #include <aclapi.h> /* for SetSecurityInfo() */
  27
  28 #include "win32_common.h"
  29 #include "wimlib_internal.h"
  30 #include "dentry.h"
  31 #include "lookup_table.h"
  32 #include "endianness.h"
  33
  34 #define MAX_CREATE_HARD_LINK_WARNINGS 5
  35 #define MAX_CREATE_SOFT_LINK_WARNINGS 5
  36
  37 #define MAX_SET_SD_ACCESS_DENIED_WARNINGS 1
  38 #define MAX_SET_SACL_PRIV_NOTHELD_WARNINGS 1
  39
  40 static const wchar_t *apply_access_denied_msg =
  41 L"If you are not running this program as the administrator, you may\n"
  42  "          need to do so, so that all data and metadata can be extracted\n"
  43  "          exactly as the origignal copy.  However, if you do not care that\n"
  44  "          the security descriptors are extracted correctly, you could run\n"
  45  "          `wimlib-imagex apply' with the --no-acls flag instead.\n"
  46  ;
  47
  48
  49 static int
  50 win32_extract_try_rpfix(u8 *rpbuf,
  51                         const wchar_t *extract_root_realpath,
  52                         unsigned extract_root_realpath_nchars)
  53 {
  54         struct reparse_data rpdata;
  55         wchar_t *target;
  56         size_t target_nchars;
  57         size_t stripped_nchars;
  58         wchar_t *stripped_target;
  59         wchar_t stripped_target_nchars;
  60         int ret;
  61
  62         utf16lechar *new_target;
  63         utf16lechar *new_print_name;
  64         size_t new_target_nchars;
  65         size_t new_print_name_nchars;
  66         utf16lechar *p;
  67
  68         ret = parse_reparse_data(rpbuf, 8 + le16_to_cpu(*(u16*)(rpbuf + 4)),
  69                                  &rpdata);
  70         if (ret)
  71                 return ret;
  72
  73         if (extract_root_realpath[0] == L'\0' ||
  74             extract_root_realpath[1] != L':' ||
  75             extract_root_realpath[2] != L'\\')
  76         {
  77                 ERROR("Can't understand full path format \"%ls\".  "
  78                       "Try turning reparse point fixups off...",
  79                       extract_root_realpath);
  80                 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
  81         }
  82
  83         ret = parse_substitute_name(rpdata.substitute_name,
  84                                     rpdata.substitute_name_nbytes,
  85                                     rpdata.rptag);
  86         if (ret < 0)
  87                 return 0;
  88         stripped_nchars = ret;
  89         target = rpdata.substitute_name;
  90         target_nchars = rpdata.substitute_name_nbytes / sizeof(utf16lechar);
  91         stripped_target = target + 6;
  92         stripped_target_nchars = target_nchars - stripped_nchars;
  93
  94         new_target = alloca((6 + extract_root_realpath_nchars +
  95                              stripped_target_nchars) * sizeof(utf16lechar));
  96
  97         p = new_target;
  98         if (stripped_nchars == 6) {
  99                 /* Include \??\ prefix if it was present before */
 100                 wmemcpy(p, L"\\??\\", 4);
 101                 p += 4;
 102         }
 103
 104         /* Print name excludes the \??\ if present. */
 105         new_print_name = p;
 106         if (stripped_nchars != 0) {
 107                 /* Get drive letter from real path to extract root, if a drive
 108                  * letter was present before. */
 109                 *p++ = extract_root_realpath[0];
 110                 *p++ = extract_root_realpath[1];
 111         }
 112         /* Copy the rest of the extract root */
 113         wmemcpy(p, extract_root_realpath + 2, extract_root_realpath_nchars - 2);
 114         p += extract_root_realpath_nchars - 2;
 115
 116         /* Append the stripped target */
 117         wmemcpy(p, stripped_target, stripped_target_nchars);
 118         p += stripped_target_nchars;
 119         new_target_nchars = p - new_target;
 120         new_print_name_nchars = p - new_print_name;
 121
 122         if (new_target_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE ||
 123             new_print_name_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE)
 124         {
 125                 ERROR("Path names too long to do reparse point fixup!");
 126                 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
 127         }
 128         rpdata.substitute_name = new_target;
 129         rpdata.substitute_name_nbytes = new_target_nchars * sizeof(utf16lechar);
 130         rpdata.print_name = new_print_name;
 131         rpdata.print_name_nbytes = new_print_name_nchars * sizeof(utf16lechar);
 132         return make_reparse_buffer(&rpdata, rpbuf);
 133 }
 134
 135 /* Wrapper around the FSCTL_SET_REPARSE_POINT ioctl to set the reparse data on
 136  * an extracted reparse point. */
 137 static int
 138 win32_set_reparse_data(HANDLE h,
 139                        const struct wim_inode *inode,
 140                        const struct wim_lookup_table_entry *lte,
 141                        const wchar_t *path,
 142                        struct apply_args *args)
 143 {
 144         int ret;
 145         u8 rpbuf[REPARSE_POINT_MAX_SIZE];
 146         DWORD bytesReturned;
 147
 148         DEBUG("Setting reparse data on \"%ls\"", path);
 149
 150         ret = wim_inode_get_reparse_data(inode, rpbuf);
 151         if (ret)
 152                 return ret;
 153
 154         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX &&
 155             (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
 156              inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT) &&
 157             !inode->i_not_rpfixed)
 158         {
 159                 ret = win32_extract_try_rpfix(rpbuf,
 160                                               args->target_realpath,
 161                                               args->target_realpath_len);
 162                 if (ret)
 163                         return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
 164         }
 165
 166         /* Set the reparse data on the open file using the
 167          * FSCTL_SET_REPARSE_POINT ioctl.
 168          *
 169          * There are contradictions in Microsoft's documentation for this:
 170          *
 171          * "If hDevice was opened without specifying FILE_FLAG_OVERLAPPED,
 172          * lpOverlapped is ignored."
 173          *
 174          * --- So setting lpOverlapped to NULL is okay since it's ignored.
 175          *
 176          * "If lpOverlapped is NULL, lpBytesReturned cannot be NULL. Even when an
 177          * operation returns no output data and lpOutBuffer is NULL,
 178          * DeviceIoControl makes use of lpBytesReturned. After such an
 179          * operation, the value of lpBytesReturned is meaningless."
 180          *
 181          * --- So lpOverlapped not really ignored, as it affects another
 182          *  parameter.  This is the actual behavior: lpBytesReturned must be
 183          *  specified, even though lpBytesReturned is documented as:
 184          *
 185          *  "Not used with this operation; set to NULL."
 186          */
 187         if (!DeviceIoControl(h, FSCTL_SET_REPARSE_POINT, rpbuf,
 188                              8 + le16_to_cpu(*(u16*)(rpbuf + 4)),
 189                              NULL, 0,
 190                              &bytesReturned /* lpBytesReturned */,
 191                              NULL /* lpOverlapped */))
 192         {
 193                 DWORD err = GetLastError();
 194                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 195                 {
 196                         args->num_soft_links_failed++;
 197                         if (args->num_soft_links_failed <= MAX_CREATE_SOFT_LINK_WARNINGS) {
 198                                 WARNING("Can't set reparse data on \"%ls\": Access denied!\n"
 199                                         "          You may be trying to extract a symbolic "
 200                                         "link without the\n"
 201                                         "          SeCreateSymbolicLink privilege, which by "
 202                                         "default non-Administrator\n"
 203                                         "          accounts do not have.", path);
 204                         }
 205                         if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS) {
 206                                 WARNING("Suppressing further warnings regarding failure to extract\n"
 207                                         "          reparse points due to insufficient privileges...");
 208                         }
 209                 } else {
 210                         ERROR("Failed to set reparse data on \"%ls\"", path);
 211                         win32_error(err);
 212                         if (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
 213                             inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT)
 214                                 return WIMLIB_ERR_LINK;
 215                         else
 216                                 return WIMLIB_ERR_WRITE;
 217                 }
 218         }
 219         return 0;
 220 }
 221
 222 /* Wrapper around the FSCTL_SET_COMPRESSION ioctl to change the
 223  * FILE_ATTRIBUTE_COMPRESSED flag of a file or directory. */
 224 static int
 225 win32_set_compression_state(HANDLE hFile, USHORT format, const wchar_t *path)
 226 {
 227         DWORD bytesReturned;
 228         if (!DeviceIoControl(hFile, FSCTL_SET_COMPRESSION,
 229                              &format, sizeof(USHORT),
 230                              NULL, 0,
 231                              &bytesReturned, NULL))
 232         {
 233                 /* Could be a warning only, but we only call this if the volume
 234                  * supports compression.  So I'm calling this an error. */
 235                 DWORD err = GetLastError();
 236                 ERROR("Failed to set compression flag on \"%ls\"", path);
 237                 win32_error(err);
 238                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 239                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 240                 else
 241                         return WIMLIB_ERR_WRITE;
 242         }
 243         return 0;
 244 }
 245
 246 /* Wrapper around FSCTL_SET_SPARSE ioctl to set a file as sparse. */
 247 static int
 248 win32_set_sparse(HANDLE hFile, const wchar_t *path)
 249 {
 250         DWORD bytesReturned;
 251         if (!DeviceIoControl(hFile, FSCTL_SET_SPARSE,
 252                              NULL, 0,
 253                              NULL, 0,
 254                              &bytesReturned, NULL))
 255         {
 256                 /* Could be a warning only, but we only call this if the volume
 257                  * supports sparse files.  So I'm calling this an error. */
 258                 DWORD err = GetLastError();
 259                 WARNING("Failed to set sparse flag on \"%ls\"", path);
 260                 win32_error(err);
 261                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 262                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 263                 else
 264                         return WIMLIB_ERR_WRITE;
 265         }
 266         return 0;
 267 }
 268
 269 /*
 270  * Sets the security descriptor on an extracted file.
 271  */
 272 static int
 273 win32_set_security_data(const struct wim_inode *inode,
 274                         HANDLE hFile,
 275                         const wchar_t *path,
 276                         struct apply_args *args)
 277 {
 278         PSECURITY_DESCRIPTOR descriptor;
 279         unsigned long n;
 280         DWORD err;
 281         const struct wim_security_data *sd;
 282
 283         SECURITY_INFORMATION securityInformation = 0;
 284
 285         void *owner = NULL;
 286         void *group = NULL;
 287         ACL *dacl = NULL;
 288         ACL *sacl = NULL;
 289
 290         BOOL owner_defaulted;
 291         BOOL group_defaulted;
 292         BOOL dacl_present;
 293         BOOL dacl_defaulted;
 294         BOOL sacl_present;
 295         BOOL sacl_defaulted;
 296
 297         sd = wim_const_security_data(args->w);
 298         descriptor = sd->descriptors[inode->i_security_id];
 299
 300         GetSecurityDescriptorOwner(descriptor, &owner, &owner_defaulted);
 301         if (owner)
 302                 securityInformation |= OWNER_SECURITY_INFORMATION;
 303
 304         GetSecurityDescriptorGroup(descriptor, &group, &group_defaulted);
 305         if (group)
 306                 securityInformation |= GROUP_SECURITY_INFORMATION;
 307
 308         GetSecurityDescriptorDacl(descriptor, &dacl_present,
 309                                   &dacl, &dacl_defaulted);
 310         if (dacl)
 311                 securityInformation |= DACL_SECURITY_INFORMATION;
 312
 313         GetSecurityDescriptorSacl(descriptor, &sacl_present,
 314                                   &sacl, &sacl_defaulted);
 315         if (sacl)
 316                 securityInformation |= SACL_SECURITY_INFORMATION;
 317
 318 again:
 319         if (securityInformation == 0)
 320                 return 0;
 321         if (SetSecurityInfo(hFile, SE_FILE_OBJECT,
 322                             securityInformation, owner, group, dacl, sacl))
 323                 return 0;
 324         err = GetLastError();
 325         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
 326                 goto fail;
 327         switch (err) {
 328         case ERROR_PRIVILEGE_NOT_HELD:
 329                 if (securityInformation & SACL_SECURITY_INFORMATION) {
 330                         n = args->num_set_sacl_priv_notheld++;
 331                         securityInformation &= ~SACL_SECURITY_INFORMATION;
 332                         sacl = NULL;
 333                         if (n < MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
 334                                 WARNING(
 335 "We don't have enough privileges to set the full security\n"
 336 "          descriptor on \"%ls\"!\n", path);
 337                                 if (args->num_set_sd_access_denied +
 338                                     args->num_set_sacl_priv_notheld == 1)
 339                                 {
 340                                         WARNING("%ls", apply_access_denied_msg);
 341                                 }
 342                                 WARNING("Re-trying with SACL omitted.\n", path);
 343                         } else if (n == MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
 344                                 WARNING(
 345 "Suppressing further 'privileges not held' error messages when setting\n"
 346 "          security descriptors.");
 347                         }
 348                         goto again;
 349                 }
 350                 /* Fall through */
 351         case ERROR_INVALID_OWNER:
 352         case ERROR_ACCESS_DENIED:
 353                 n = args->num_set_sd_access_denied++;
 354                 if (n < MAX_SET_SD_ACCESS_DENIED_WARNINGS) {
 355                         WARNING("Failed to set security descriptor on \"%ls\": "
 356                                 "Access denied!\n", path);
 357                         if (args->num_set_sd_access_denied +
 358                             args->num_set_sacl_priv_notheld == 1)
 359                         {
 360                                 WARNING("%ls", apply_access_denied_msg);
 361                         }
 362                 } else if (n == MAX_SET_SD_ACCESS_DENIED_WARNINGS) {
 363                         WARNING(
 364 "Suppressing further access denied error messages when setting\n"
 365 "          security descriptors");
 366                 }
 367                 return 0;
 368         default:
 369 fail:
 370                 ERROR("Failed to set security descriptor on \"%ls\"", path);
 371                 win32_error(err);
 372                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 373                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 374                 else
 375                         return WIMLIB_ERR_WRITE;
 376         }
 377 }
 378
 379
 380 static int
 381 win32_extract_chunk(const void *buf, size_t len, void *arg)
 382 {
 383         HANDLE hStream = arg;
 384
 385         DWORD nbytes_written;
 386         wimlib_assert(len <= 0xffffffff);
 387
 388         if (!WriteFile(hStream, buf, len, &nbytes_written, NULL) ||
 389             nbytes_written != len)
 390         {
 391                 DWORD err = GetLastError();
 392                 ERROR("WriteFile(): write error");
 393                 win32_error(err);
 394                 return WIMLIB_ERR_WRITE;
 395         }
 396         return 0;
 397 }
 398
 399 static int
 400 do_win32_extract_stream(HANDLE hStream, const struct wim_lookup_table_entry *lte)
 401 {
 402         return extract_wim_resource(lte, wim_resource_size(lte),
 403                                     win32_extract_chunk, hStream);
 404 }
 405
 406 struct win32_encrypted_extract_ctx {
 407         const struct wim_lookup_table_entry *lte;
 408         u64 offset;
 409 };
 410
 411 static DWORD WINAPI
 412 win32_encrypted_import_cb(unsigned char *data, void *_ctx,
 413                           unsigned long *len_p)
 414 {
 415         struct win32_encrypted_extract_ctx *ctx = _ctx;
 416         unsigned long len = *len_p;
 417         const struct wim_lookup_table_entry *lte = ctx->lte;
 418
 419         len = min(len, wim_resource_size(lte) - ctx->offset);
 420
 421         if (read_partial_wim_resource_into_buf(lte, len, ctx->offset, data))
 422                 return ERROR_READ_FAULT;
 423
 424         ctx->offset += len;
 425         *len_p = len;
 426         return ERROR_SUCCESS;
 427 }
 428
 429 /* Create an encrypted file and extract the raw encrypted data to it.
 430  *
 431  * @path:  Path to encrypted file to create.
 432  * @lte:   WIM lookup_table entry for the raw encrypted data.
 433  *
 434  * This is separate from do_win32_extract_stream() because the WIM is supposed
 435  * to contain the *raw* encrypted data, which needs to be extracted ("imported")
 436  * using the special APIs OpenEncryptedFileRawW(), WriteEncryptedFileRaw(), and
 437  * CloseEncryptedFileRaw().
 438  *
 439  * Returns 0 on success; nonzero on failure.
 440  */
 441 static int
 442 do_win32_extract_encrypted_stream(const wchar_t *path,
 443                                   const struct wim_lookup_table_entry *lte)
 444 {
 445         void *file_ctx;
 446         int ret;
 447
 448         DEBUG("Opening file \"%ls\" to extract raw encrypted data", path);
 449
 450         ret = OpenEncryptedFileRawW(path, CREATE_FOR_IMPORT, &file_ctx);
 451         if (ret) {
 452                 ERROR("Failed to open \"%ls\" to write raw encrypted data", path);
 453                 win32_error(ret);
 454                 return WIMLIB_ERR_OPEN;
 455         }
 456
 457         if (lte) {
 458                 struct win32_encrypted_extract_ctx ctx;
 459
 460                 ctx.lte = lte;
 461                 ctx.offset = 0;
 462                 ret = WriteEncryptedFileRaw(win32_encrypted_import_cb, &ctx, file_ctx);
 463                 if (ret == ERROR_SUCCESS) {
 464                         ret = 0;
 465                 } else {
 466                         ret = WIMLIB_ERR_WRITE;
 467                         ERROR("Failed to extract encrypted file \"%ls\"", path);
 468                 }
 469         }
 470         CloseEncryptedFileRaw(file_ctx);
 471         return ret;
 472 }
 473
 474 static bool
 475 path_is_root_of_drive(const wchar_t *path)
 476 {
 477         if (!*path)
 478                 return false;
 479
 480         if (*path != L'/' && *path != L'\\') {
 481                 if (*(path + 1) == L':')
 482                         path += 2;
 483                 else
 484                         return false;
 485         }
 486         while (*path == L'/' || *path == L'\\')
 487                 path++;
 488         return (*path == L'\0');
 489 }
 490
 491 static inline DWORD
 492 win32_mask_attributes(DWORD i_attributes)
 493 {
 494         return i_attributes & ~(FILE_ATTRIBUTE_SPARSE_FILE |
 495                                 FILE_ATTRIBUTE_COMPRESSED |
 496                                 FILE_ATTRIBUTE_REPARSE_POINT |
 497                                 FILE_ATTRIBUTE_DIRECTORY |
 498                                 FILE_ATTRIBUTE_ENCRYPTED |
 499                                 FILE_FLAG_DELETE_ON_CLOSE |
 500                                 FILE_FLAG_NO_BUFFERING |
 501                                 FILE_FLAG_OPEN_NO_RECALL |
 502                                 FILE_FLAG_OVERLAPPED |
 503                                 FILE_FLAG_RANDOM_ACCESS |
 504                                 /*FILE_FLAG_SESSION_AWARE |*/
 505                                 FILE_FLAG_SEQUENTIAL_SCAN |
 506                                 FILE_FLAG_WRITE_THROUGH);
 507 }
 508
 509 static inline DWORD
 510 win32_get_create_flags_and_attributes(DWORD i_attributes)
 511 {
 512         /*
 513          * Some attributes cannot be set by passing them to CreateFile().  In
 514          * particular:
 515          *
 516          * FILE_ATTRIBUTE_DIRECTORY:
 517          *   CreateDirectory() must be called instead of CreateFile().
 518          *
 519          * FILE_ATTRIBUTE_SPARSE_FILE:
 520          *   Needs an ioctl.
 521          *   See: win32_set_sparse().
 522          *
 523          * FILE_ATTRIBUTE_COMPRESSED:
 524          *   Not clear from the documentation, but apparently this needs an
 525          *   ioctl as well.
 526          *   See: win32_set_compressed().
 527          *
 528          * FILE_ATTRIBUTE_REPARSE_POINT:
 529          *   Needs an ioctl, with the reparse data specified.
 530          *   See: win32_set_reparse_data().
 531          *
 532          * In addition, clear any file flags in the attributes that we don't
 533          * want, but also specify FILE_FLAG_OPEN_REPARSE_POINT and
 534          * FILE_FLAG_BACKUP_SEMANTICS as we are a backup application.
 535          */
 536         return win32_mask_attributes(i_attributes) |
 537                 FILE_FLAG_OPEN_REPARSE_POINT |
 538                 FILE_FLAG_BACKUP_SEMANTICS;
 539 }
 540
 541 /* Set compression and/or sparse attributes on a stream, if supported by the
 542  * volume. */
 543 static int
 544 win32_set_special_stream_attributes(HANDLE hFile, const struct wim_inode *inode,
 545                                     struct wim_lookup_table_entry *unnamed_stream_lte,
 546                                     const wchar_t *path, unsigned vol_flags)
 547 {
 548         int ret;
 549
 550         if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
 551                 if (vol_flags & FILE_FILE_COMPRESSION) {
 552                         ret = win32_set_compression_state(hFile,
 553                                                           COMPRESSION_FORMAT_DEFAULT,
 554                                                           path);
 555                         if (ret)
 556                                 return ret;
 557                 } else {
 558                         DEBUG("Cannot set compression attribute on \"%ls\": "
 559                               "volume does not support transparent compression",
 560                               path);
 561                 }
 562         }
 563
 564         if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE) {
 565                 if (vol_flags & FILE_SUPPORTS_SPARSE_FILES) {
 566                         DEBUG("Setting sparse flag on \"%ls\"", path);
 567                         ret = win32_set_sparse(hFile, path);
 568                         if (ret)
 569                                 return ret;
 570                 } else {
 571                         DEBUG("Cannot set sparse attribute on \"%ls\": "
 572                               "volume does not support sparse files",
 573                               path);
 574                 }
 575         }
 576         return 0;
 577 }
 578
 579 /* Pre-create directories; extract encrypted streams */
 580 static int
 581 win32_begin_extract_unnamed_stream(const struct wim_inode *inode,
 582                                    const struct wim_lookup_table_entry *lte,
 583                                    const wchar_t *path,
 584                                    DWORD *creationDisposition_ret,
 585                                    unsigned int vol_flags)
 586 {
 587         DWORD err;
 588         int ret;
 589
 590         /* Directories must be created with CreateDirectoryW().  Then the call
 591          * to CreateFileW() will merely open the directory that was already
 592          * created rather than creating a new file. */
 593         if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY &&
 594             !path_is_root_of_drive(path)) {
 595                 if (!CreateDirectoryW(path, NULL)) {
 596                         err = GetLastError();
 597                         if (err != ERROR_ALREADY_EXISTS) {
 598                                 ERROR("Failed to create directory \"%ls\"",
 599                                       path);
 600                                 win32_error(err);
 601                                 return WIMLIB_ERR_MKDIR;
 602                         }
 603                 }
 604                 DEBUG("Created directory \"%ls\"", path);
 605                 *creationDisposition_ret = OPEN_EXISTING;
 606         }
 607         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED &&
 608             vol_flags & FILE_SUPPORTS_ENCRYPTION)
 609         {
 610                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
 611                         unsigned remaining_sharing_violations = 100;
 612                         while (!EncryptFile(path)) {
 613                                 if (remaining_sharing_violations &&
 614                                     err == ERROR_SHARING_VIOLATION)
 615                                 {
 616                                         WARNING("Couldn't encrypt directory \"%ls\" "
 617                                                 "due to sharing violation; re-trying "
 618                                                 "after 100 ms", path);
 619                                         Sleep(100);
 620                                         remaining_sharing_violations--;
 621                                 } else {
 622                                         err = GetLastError();
 623                                         ERROR("Failed to encrypt directory \"%ls\"",
 624                                               path);
 625                                         win32_error(err);
 626                                         return WIMLIB_ERR_WRITE;
 627                                 }
 628                         }
 629                 } else {
 630                         ret = do_win32_extract_encrypted_stream(path, lte);
 631                         if (ret)
 632                                 return ret;
 633                         DEBUG("Extracted encrypted file \"%ls\"", path);
 634                 }
 635                 *creationDisposition_ret = OPEN_EXISTING;
 636         }
 637
 638         /* Set file attributes if we created the file.  Otherwise, we haven't
 639          * created the file set and we will set the attributes in the call to
 640          * CreateFileW().
 641          *
 642          * The FAT filesystem does not let you change the attributes of the root
 643          * directory, so treat that as a special case and do not set attributes.
 644          * */
 645         if (*creationDisposition_ret == OPEN_EXISTING &&
 646             !path_is_root_of_drive(path))
 647         {
 648                 if (!SetFileAttributesW(path,
 649                                         win32_mask_attributes(inode->i_attributes)))
 650                 {
 651                         err = GetLastError();
 652                         ERROR("Failed to set attributes on \"%ls\"", path);
 653                         win32_error(err);
 654                         return WIMLIB_ERR_WRITE;
 655                 }
 656         }
 657         return 0;
 658 }
 659
 660 /* Set security descriptor and extract stream data or reparse data (skip the
 661  * unnamed data stream of encrypted files, which was already extracted). */
 662 static int
 663 win32_finish_extract_stream(HANDLE h, const struct wim_dentry *dentry,
 664                             const struct wim_lookup_table_entry *lte,
 665                             const wchar_t *stream_path,
 666                             const wchar_t *stream_name_utf16,
 667                             struct apply_args *args)
 668 {
 669         int ret = 0;
 670         const struct wim_inode *inode = dentry->d_inode;
 671         if (stream_name_utf16 == NULL) {
 672                 /* Unnamed stream. */
 673
 674                 /* Set security descriptor, unless the extract_flags indicate
 675                  * not to or the volume does not supported it.  Note that this
 676                  * is only done when the unnamed stream is being extracted, as
 677                  * security descriptors are per-file and not per-stream. */
 678                 if (inode->i_security_id >= 0 &&
 679                     !(args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
 680                     && (args->vol_flags & FILE_PERSISTENT_ACLS))
 681                 {
 682                         ret = win32_set_security_data(inode, h, stream_path, args);
 683                         if (ret)
 684                                 return ret;
 685                 }
 686
 687                 /* Handle reparse points.  The data for them needs to be set
 688                  * using a special ioctl.  Note that the reparse point may have
 689                  * been created using CreateFileW() in the case of
 690                  * non-directories or CreateDirectoryW() in the case of
 691                  * directories; but the ioctl works either way.  Also, it is
 692                  * only this step that actually sets the
 693                  * FILE_ATTRIBUTE_REPARSE_POINT, as it is not valid to set it
 694                  * using SetFileAttributesW() or CreateFileW().
 695                  *
 696                  * If the volume does not support reparse points we simply
 697                  * ignore the reparse data.  (N.B. the code currently doesn't
 698                  * actually reach this case because reparse points are skipped
 699                  * entirely on such volumes.) */
 700                 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 701                         if (args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS) {
 702                                 ret = win32_set_reparse_data(h, inode,
 703                                                              lte, stream_path,
 704                                                              args);
 705                                 if (ret)
 706                                         return ret;
 707                         } else {
 708                                 DEBUG("Cannot set reparse data on \"%ls\": volume "
 709                                       "does not support reparse points", stream_path);
 710                         }
 711                 } else if (lte != NULL &&
 712                            !(args->vol_flags & FILE_SUPPORTS_ENCRYPTION &&
 713                              inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
 714                 {
 715                         /* Extract the data of the unnamed stream, unless the
 716                          * lookup table entry is NULL (indicating an empty
 717                          * stream for which no data needs to be extracted), or
 718                          * the stream is encrypted and therefore was already
 719                          * extracted as a special case. */
 720                         ret = do_win32_extract_stream(h, lte);
 721                         if (ret)
 722                                 return ret;
 723                 }
 724
 725                 if (dentry_has_short_name(dentry))
 726                         SetFileShortNameW(h, dentry->short_name);
 727                 else if (running_on_windows_7_or_later())
 728                         SetFileShortNameW(h, L"");
 729         } else {
 730                 /* Extract the data for a named data stream. */
 731                 if (lte != NULL) {
 732                         DEBUG("Extracting named data stream \"%ls\" (len = %"PRIu64")",
 733                               stream_path, wim_resource_size(lte));
 734                         ret = do_win32_extract_stream(h, lte);
 735                 }
 736         }
 737         return ret;
 738 }
 739
 740 static int
 741 win32_decrypt_file(HANDLE open_handle, const wchar_t *path)
 742 {
 743         DWORD err;
 744         /* We cannot call DecryptFileW() while there is an open handle to the
 745          * file.  So close it first. */
 746         if (!CloseHandle(open_handle)) {
 747                 err = GetLastError();
 748                 ERROR("Failed to close handle for \"%ls\"", path);
 749                 win32_error(err);
 750                 return WIMLIB_ERR_WRITE;
 751         }
 752         if (!DecryptFileW(path, 0 /* reserved parameter; set to 0 */)) {
 753                 err = GetLastError();
 754                 ERROR("Failed to decrypt file \"%ls\"", path);
 755                 win32_error(err);
 756                 return WIMLIB_ERR_WRITE;
 757         }
 758         return 0;
 759 }
 760
 761 /*
 762  * Create and extract a stream to a file, or create a directory, using the
 763  * Windows API.
 764  *
 765  * This handles reparse points, directories, alternate data streams, encrypted
 766  * files, compressed files, etc.
 767  *
 768  * @dentry: WIM dentry for the file or directory being extracted.
 769  *
 770  * @path:  Path to extract the file to.
 771  *
 772  * @stream_name_utf16:
 773  *         Name of the stream, or NULL if the stream is unnamed.  This will
 774  *         be called with a NULL stream_name_utf16 before any non-NULL
 775  *         stream_name_utf16's.
 776  *
 777  * @lte:   WIM lookup table entry for the stream.  May be NULL to indicate
 778  *         a stream of length 0.
 779  *
 780  * @args:  Additional apply context, including flags indicating supported
 781  *         volume features.
 782  *
 783  * Returns 0 on success; nonzero on failure.
 784  */
 785 static int
 786 win32_extract_stream(const struct wim_dentry *dentry,
 787                      const wchar_t *path,
 788                      const wchar_t *stream_name_utf16,
 789                      struct wim_lookup_table_entry *lte,
 790                      struct apply_args *args)
 791 {
 792         wchar_t *stream_path;
 793         HANDLE h;
 794         int ret;
 795         DWORD err;
 796         DWORD creationDisposition = CREATE_ALWAYS;
 797         DWORD requestedAccess;
 798         BY_HANDLE_FILE_INFORMATION file_info;
 799         unsigned remaining_sharing_violations = 1000;
 800         const struct wim_inode *inode = dentry->d_inode;
 801
 802         if (stream_name_utf16) {
 803                 /* Named stream.  Create a buffer that contains the UTF-16LE
 804                  * string [./]path:stream_name_utf16.  This is needed to
 805                  * create and open the stream using CreateFileW().  I'm not
 806                  * aware of any other APIs to do this.  Note: the '$DATA' suffix
 807                  * seems to be unneeded.  Additional note: a "./" prefix needs
 808                  * to be added when the path is not absolute to avoid ambiguity
 809                  * with drive letters. */
 810                 size_t stream_path_nchars;
 811                 size_t path_nchars;
 812                 size_t stream_name_nchars;
 813                 const wchar_t *prefix;
 814
 815                 path_nchars = wcslen(path);
 816                 stream_name_nchars = wcslen(stream_name_utf16);
 817                 stream_path_nchars = path_nchars + 1 + stream_name_nchars;
 818                 if (path[0] != cpu_to_le16(L'\0') &&
 819                     path[0] != cpu_to_le16(L'/') &&
 820                     path[0] != cpu_to_le16(L'\\') &&
 821                     path[1] != cpu_to_le16(L':'))
 822                 {
 823                         prefix = L"./";
 824                         stream_path_nchars += 2;
 825                 } else {
 826                         prefix = L"";
 827                 }
 828                 stream_path = alloca((stream_path_nchars + 1) * sizeof(wchar_t));
 829                 swprintf(stream_path, L"%ls%ls:%ls",
 830                          prefix, path, stream_name_utf16);
 831         } else {
 832                 /* Unnamed stream; its path is just the path to the file itself.
 833                  * */
 834                 stream_path = (wchar_t*)path;
 835
 836                 ret = win32_begin_extract_unnamed_stream(inode, lte, path,
 837                                                          &creationDisposition,
 838                                                          args->vol_flags);
 839                 if (ret)
 840                         goto fail;
 841         }
 842
 843         DEBUG("Opening \"%ls\"", stream_path);
 844         /* DELETE access is needed for SetFileShortNameW(), for some reason. */
 845         requestedAccess = GENERIC_READ | GENERIC_WRITE | DELETE |
 846                           ACCESS_SYSTEM_SECURITY;
 847 try_open_again:
 848         /* Open the stream to be extracted.  Depending on what we have set
 849          * creationDisposition to, we may be creating this for the first time,
 850          * or we may be opening on existing stream we already created using
 851          * CreateDirectoryW() or OpenEncryptedFileRawW(). */
 852         h = CreateFileW(stream_path,
 853                         requestedAccess,
 854                         FILE_SHARE_READ,
 855                         NULL,
 856                         creationDisposition,
 857                         win32_get_create_flags_and_attributes(inode->i_attributes),
 858                         NULL);
 859         if (h == INVALID_HANDLE_VALUE) {
 860                 err = GetLastError();
 861                 if (err == ERROR_ACCESS_DENIED &&
 862                     path_is_root_of_drive(stream_path))
 863                 {
 864                         ret = 0;
 865                         goto out;
 866                 }
 867                 if ((err == ERROR_PRIVILEGE_NOT_HELD ||
 868                      err == ERROR_ACCESS_DENIED) &&
 869                     (requestedAccess & ACCESS_SYSTEM_SECURITY))
 870                 {
 871                         /* Try opening the file again without privilege to
 872                          * modify SACL. */
 873                         requestedAccess &= ~ACCESS_SYSTEM_SECURITY;
 874                         goto try_open_again;
 875                 }
 876                 if (err == ERROR_SHARING_VIOLATION) {
 877                         if (remaining_sharing_violations) {
 878                                 --remaining_sharing_violations;
 879                                 /* This can happen when restoring encrypted directories
 880                                  * for some reason.  Probably a bug in EncryptFile(). */
 881                                 WARNING("Couldn't open \"%ls\" due to sharing violation; "
 882                                         "re-trying after 100ms", stream_path);
 883                                 Sleep(100);
 884                                 goto try_open_again;
 885                         } else {
 886                                 ERROR("Too many sharing violations; giving up...");
 887                         }
 888                 } else {
 889                         if (creationDisposition == OPEN_EXISTING)
 890                                 ERROR("Failed to open \"%ls\"", stream_path);
 891                         else
 892                                 ERROR("Failed to create \"%ls\"", stream_path);
 893                         win32_error(err);
 894                 }
 895                 ret = WIMLIB_ERR_OPEN;
 896                 goto fail;
 897         }
 898
 899         /* Check the attributes of the file we just opened, and remove
 900          * encryption or compression if either was set by default but is not
 901          * supposed to be set based on the WIM inode attributes. */
 902         if (!GetFileInformationByHandle(h, &file_info)) {
 903                 err = GetLastError();
 904                 ERROR("Failed to get attributes of \"%ls\"", stream_path);
 905                 win32_error(err);
 906                 ret = WIMLIB_ERR_STAT;
 907                 goto fail_close_handle;
 908         }
 909
 910         /* Remove encryption? */
 911         if (file_info.dwFileAttributes & FILE_ATTRIBUTE_ENCRYPTED &&
 912             !(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
 913         {
 914                 /* File defaulted to encrypted due to being in an encrypted
 915                  * directory, but is not actually supposed to be encrypted.
 916                  *
 917                  * This is a workaround, because I'm not aware of any way to
 918                  * directly (e.g. with CreateFileW()) create an unencrypted file
 919                  * in a directory with FILE_ATTRIBUTE_ENCRYPTED set. */
 920                 ret = win32_decrypt_file(h, stream_path);
 921                 if (ret)
 922                         goto fail; /* win32_decrypt_file() closed the handle. */
 923                 creationDisposition = OPEN_EXISTING;
 924                 goto try_open_again;
 925         }
 926
 927         /* Remove compression? */
 928         if (file_info.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED &&
 929             !(inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED))
 930         {
 931                 /* Similar to the encrypted case, above, if the file defaulted
 932                  * to compressed due to being in an compressed directory, but is
 933                  * not actually supposed to be compressed, explicitly set the
 934                  * compression format to COMPRESSION_FORMAT_NONE. */
 935                 ret = win32_set_compression_state(h, COMPRESSION_FORMAT_NONE,
 936                                                   stream_path);
 937                 if (ret)
 938                         goto fail_close_handle;
 939         }
 940
 941         /* Set compression and/or sparse attributes if needed */
 942         ret = win32_set_special_stream_attributes(h, inode, lte, path,
 943                                                   args->vol_flags);
 944
 945         if (ret)
 946                 goto fail_close_handle;
 947
 948         /* At this point we have at least created the needed stream with the
 949          * appropriate attributes.  We have yet to set the appropriate security
 950          * descriptor and actually extract the stream data (other than for
 951          * extracted files, which were already extracted).
 952          * win32_finish_extract_stream() handles these additional steps. */
 953         ret = win32_finish_extract_stream(h, dentry, lte, stream_path,
 954                                           stream_name_utf16, args);
 955         if (ret)
 956                 goto fail_close_handle;
 957
 958         /* Done extracting the stream.  Close the handle and return. */
 959         DEBUG("Closing \"%ls\"", stream_path);
 960         if (!CloseHandle(h)) {
 961                 err = GetLastError();
 962                 ERROR("Failed to close \"%ls\"", stream_path);
 963                 win32_error(err);
 964                 ret = WIMLIB_ERR_WRITE;
 965                 goto fail;
 966         }
 967         ret = 0;
 968         goto out;
 969 fail_close_handle:
 970         CloseHandle(h);
 971 fail:
 972         ERROR("Error extracting \"%ls\"", stream_path);
 973 out:
 974         return ret;
 975 }
 976
 977 /*
 978  * Creates a file, directory, or reparse point and extracts all streams to it
 979  * (unnamed data stream and/or reparse point stream, plus any alternate data
 980  * streams).  Handles sparse, compressed, and/or encrypted files.
 981  *
 982  * @dentry:     WIM dentry for this file or directory.
 983  * @path:       UTF-16LE external path to extract the inode to.
 984  * @args:       Additional extraction context.
 985  *
 986  * Returns 0 on success; nonzero on failure.
 987  */
 988 static int
 989 win32_extract_streams(const struct wim_dentry *dentry,
 990                       const wchar_t *path, struct apply_args *args)
 991 {
 992         struct wim_lookup_table_entry *unnamed_lte;
 993         int ret;
 994         const struct wim_inode *inode = dentry->d_inode;
 995
 996         /* First extract the unnamed stream. */
 997
 998         unnamed_lte = inode_unnamed_lte_resolved(inode);
 999         ret = win32_extract_stream(dentry, path, NULL, unnamed_lte, args);
1000         if (ret)
1001                 goto out;
1002
1003         /* Extract any named streams, if supported by the volume. */
1004
1005         if (!(args->vol_flags & FILE_NAMED_STREAMS))
1006                 goto out;
1007         for (u16 i = 0; i < inode->i_num_ads; i++) {
1008                 const struct wim_ads_entry *ads_entry = &inode->i_ads_entries[i];
1009
1010                 /* Skip the unnamed stream if it's in the ADS entries (we
1011                  * already extracted it...) */
1012                 if (ads_entry->stream_name_nbytes == 0)
1013                         continue;
1014
1015                 /* Skip special UNIX data entries (see documentation for
1016                  * WIMLIB_ADD_FLAG_UNIX_DATA) */
1017                 if (ads_entry->stream_name_nbytes == WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES
1018                     && !memcmp(ads_entry->stream_name,
1019                                WIMLIB_UNIX_DATA_TAG_UTF16LE,
1020                                WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES))
1021                         continue;
1022
1023                 /* Extract the named stream */
1024                 ret = win32_extract_stream(dentry,
1025                                            path,
1026                                            ads_entry->stream_name,
1027                                            ads_entry->lte,
1028                                            args);
1029                 if (ret)
1030                         break;
1031         }
1032 out:
1033         return ret;
1034 }
1035
1036 static int
1037 dentry_clear_inode_visited(struct wim_dentry *dentry, void *_ignore)
1038 {
1039         dentry->d_inode->i_visited = 0;
1040         return 0;
1041 }
1042
1043 static int
1044 dentry_get_features(struct wim_dentry *dentry, void *_features_p)
1045 {
1046         DWORD features = 0;
1047         DWORD *features_p = _features_p;
1048         struct wim_inode *inode = dentry->d_inode;
1049
1050         if (inode->i_visited) {
1051                 features |= FILE_SUPPORTS_HARD_LINKS;
1052         } else {
1053                 inode->i_visited = 1;
1054                 if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE)
1055                         features |= FILE_SUPPORTS_SPARSE_FILES;
1056                 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)
1057                         features |= FILE_SUPPORTS_REPARSE_POINTS;
1058                 for (unsigned i = 0; i < inode->i_num_ads; i++)
1059                         if (inode->i_ads_entries[i].stream_name_nbytes)
1060                                 features |= FILE_NAMED_STREAMS;
1061                 if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED)
1062                         features |= FILE_SUPPORTS_ENCRYPTION;
1063                 if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED)
1064                         features |= FILE_FILE_COMPRESSION;
1065                 if (inode->i_security_id != -1)
1066                         features |= FILE_PERSISTENT_ACLS;
1067         }
1068         *features_p |= features;
1069         return 0;
1070 }
1071
1072 /* If not done already, load the supported feature flags for the volume onto
1073  * which the image is being extracted, and warn the user about any missing
1074  * features that could be important. */
1075 static int
1076 win32_check_vol_flags(const wchar_t *output_path,
1077                       struct wim_dentry *root, struct apply_args *args)
1078 {
1079         DWORD dentry_features = 0;
1080         DWORD missing_features;
1081
1082         if (args->have_vol_flags)
1083                 return 0;
1084
1085         for_dentry_in_tree(root, dentry_clear_inode_visited, NULL);
1086         for_dentry_in_tree(root, dentry_get_features, &dentry_features);
1087
1088         win32_get_vol_flags(output_path, &args->vol_flags);
1089         args->have_vol_flags = true;
1090
1091         missing_features = dentry_features & ~args->vol_flags;
1092
1093         /* Warn the user about data that may not be extracted. */
1094         if (missing_features & FILE_SUPPORTS_SPARSE_FILES)
1095                 WARNING("Volume does not support sparse files!\n"
1096                         "          Sparse files will be extracted as non-sparse.");
1097         if (missing_features & FILE_SUPPORTS_REPARSE_POINTS)
1098                 WARNING("Volume does not support reparse points!\n"
1099                         "          Reparse point data will not be extracted.");
1100         if (missing_features & FILE_NAMED_STREAMS) {
1101                 WARNING("Volume does not support named data streams!\n"
1102                         "          Named data streams will not be extracted.");
1103         }
1104         if (missing_features & FILE_SUPPORTS_ENCRYPTION) {
1105                 WARNING("Volume does not support encryption!\n"
1106                         "          Encrypted files will be extracted as raw data.");
1107         }
1108         if (missing_features & FILE_FILE_COMPRESSION) {
1109                 WARNING("Volume does not support transparent compression!\n"
1110                         "          Compressed files will be extracted as non-compressed.");
1111         }
1112         if (missing_features & FILE_PERSISTENT_ACLS) {
1113                 if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
1114                         ERROR("Strict ACLs requested, but the volume does not "
1115                               "support ACLs!");
1116                         return WIMLIB_ERR_VOLUME_LACKS_FEATURES;
1117                 } else {
1118                         WARNING("Volume does not support persistent ACLS!\n"
1119                                 "          File permissions will not be extracted.");
1120                 }
1121         }
1122         if (running_on_windows_7_or_later() &&
1123             (missing_features & FILE_SUPPORTS_HARD_LINKS))
1124         {
1125                 WARNING("Volume does not support hard links!\n"
1126                         "          Hard links will be extracted as duplicate files.");
1127         }
1128         return 0;
1129 }
1130
1131 /*
1132  * Try extracting a hard link.
1133  *
1134  * @output_path:  Path to link to be extracted.
1135  *
1136  * @inode:        WIM inode that the link is to; inode->i_extracted_file
1137  *                the path to a name of the file that has already been
1138  *                extracted (we use this to create the hard link).
1139  *
1140  * @args:         Additional apply context, used here to keep track of
1141  *                the number of times creating a hard link failed due to
1142  *                ERROR_INVALID_FUNCTION.  This error should indicate that hard
1143  *                links are not supported by the volume, and we would like to
1144  *                warn the user a few times, but not too many times.
1145  *
1146  * Returns 0 if the hard link was successfully extracted.  Returns
1147  * WIMLIB_ERR_LINK (> 0) if an error occurred, other than hard links possibly
1148  * being unsupported by the volume.  Returns a negative value if creating the
1149  * hard link failed due to ERROR_INVALID_FUNCTION.
1150  */
1151 static int
1152 win32_try_hard_link(const wchar_t *output_path, const struct wim_inode *inode,
1153                     struct apply_args *args)
1154 {
1155         DWORD err;
1156
1157         /* There is a volume flag for this (FILE_SUPPORTS_HARD_LINKS),
1158          * but it's only available on Windows 7 and later.
1159          *
1160          * Otherwise, CreateHardLinkW() will apparently return
1161          * ERROR_INVALID_FUNCTION if the volume does not support hard links. */
1162
1163         DEBUG("Creating hard link \"%ls => %ls\"",
1164               output_path, inode->i_extracted_file);
1165
1166         if (running_on_windows_7_or_later() &&
1167             !(args->vol_flags & FILE_SUPPORTS_HARD_LINKS))
1168                 goto hard_links_unsupported;
1169
1170         if (CreateHardLinkW(output_path, inode->i_extracted_file, NULL))
1171                 return 0;
1172
1173         err = GetLastError();
1174         if (err != ERROR_INVALID_FUNCTION) {
1175                 ERROR("Can't create hard link \"%ls => %ls\"",
1176                       output_path, inode->i_extracted_file);
1177                 win32_error(err);
1178                 return WIMLIB_ERR_LINK;
1179         }
1180 hard_links_unsupported:
1181         args->num_hard_links_failed++;
1182         if (args->num_hard_links_failed <= MAX_CREATE_HARD_LINK_WARNINGS) {
1183                 if (running_on_windows_7_or_later())
1184                 {
1185                         WARNING("Extracting duplicate copy of \"%ls\" "
1186                                 "rather than hard link", output_path);
1187                 } else {
1188                         WARNING("Can't create hard link \"%ls\" => \"%ls\":\n"
1189                                 "          Volume does not support hard links!\n"
1190                                 "          Falling back to extracting a copy of the file.",
1191                                 output_path, inode->i_extracted_file);
1192                 }
1193         }
1194         if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS)
1195                 WARNING("Suppressing further hard linking warnings...");
1196         return -1;
1197 }
1198
1199 /* Extract a file, directory, reparse point, or hard link to an
1200  * already-extracted file using the Win32 API */
1201 int
1202 win32_do_apply_dentry(const wchar_t *output_path,
1203                       size_t output_path_num_chars,
1204                       struct wim_dentry *dentry,
1205                       struct apply_args *args)
1206 {
1207         int ret;
1208         struct wim_inode *inode = dentry->d_inode;
1209
1210         ret = win32_check_vol_flags(output_path, dentry, args);
1211         if (ret)
1212                 return ret;
1213         if (inode->i_nlink > 1 && inode->i_extracted_file != NULL) {
1214                 /* Linked file, with another name already extracted.  Create a
1215                  * hard link. */
1216                 ret = win32_try_hard_link(output_path, inode, args);
1217                 if (ret >= 0)
1218                         return ret;
1219                 /* Negative return value from win32_try_hard_link() indicates
1220                  * that hard links are probably not supported by the volume.
1221                  * Fall back to extracting a copy of the file. */
1222         }
1223
1224         /* If this is a reparse point and the volume does not support reparse
1225          * points, just skip it completely. */
1226         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
1227             !(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
1228         {
1229                 WARNING("Not extracting reparse point \"%ls\"", output_path);
1230         } else {
1231                 /* Create the file, directory, or reparse point, and extract the
1232                  * data streams. */
1233                 ret = win32_extract_streams(dentry, output_path, args);
1234                 if (ret)
1235                         return ret;
1236         }
1237         if (inode->i_extracted_file == NULL) {
1238                 const struct wim_lookup_table_entry *lte;
1239
1240                 /* Tally bytes extracted, including all alternate data streams,
1241                  * unless we extracted a hard link (or, at least extracted a
1242                  * name that was supposed to be a hard link) */
1243                 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1244                         lte = inode_stream_lte_resolved(inode, i);
1245                         if (lte)
1246                                 args->progress.extract.completed_bytes +=
1247                                                         wim_resource_size(lte);
1248                 }
1249                 if (inode->i_nlink > 1) {
1250                         /* Save extracted path for a later call to
1251                          * CreateHardLinkW() if this inode has multiple links.
1252                          * */
1253                         inode->i_extracted_file = WSTRDUP(output_path);
1254                         if (!inode->i_extracted_file)
1255                                 return WIMLIB_ERR_NOMEM;
1256                 }
1257         }
1258         return 0;
1259 }
1260
1261 /* Set timestamps on an extracted file using the Win32 API */
1262 int
1263 win32_do_apply_dentry_timestamps(const wchar_t *path,
1264                                  size_t path_num_chars,
1265                                  struct wim_dentry *dentry,
1266                                  struct apply_args *args)
1267 {
1268         DWORD err;
1269         HANDLE h;
1270         const struct wim_inode *inode = dentry->d_inode;
1271
1272         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
1273             !(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
1274         {
1275                 /* Skip reparse points not extracted */
1276                 return 0;
1277         }
1278
1279         /* Windows doesn't let you change the timestamps of the root directory
1280          * (at least on FAT, which is dumb but expected since FAT doesn't store
1281          * any metadata about the root directory...) */
1282         if (path_is_root_of_drive(path))
1283                 return 0;
1284
1285         DEBUG("Opening \"%ls\" to set timestamps", path);
1286         h = win32_open_existing_file(path, FILE_WRITE_ATTRIBUTES);
1287         if (h == INVALID_HANDLE_VALUE) {
1288                 err = GetLastError();
1289                 goto fail;
1290         }
1291
1292         FILETIME creationTime = {.dwLowDateTime = inode->i_creation_time & 0xffffffff,
1293                                  .dwHighDateTime = inode->i_creation_time >> 32};
1294         FILETIME lastAccessTime = {.dwLowDateTime = inode->i_last_access_time & 0xffffffff,
1295                                   .dwHighDateTime = inode->i_last_access_time >> 32};
1296         FILETIME lastWriteTime = {.dwLowDateTime = inode->i_last_write_time & 0xffffffff,
1297                                   .dwHighDateTime = inode->i_last_write_time >> 32};
1298
1299         DEBUG("Calling SetFileTime() on \"%ls\"", path);
1300         if (!SetFileTime(h, &creationTime, &lastAccessTime, &lastWriteTime)) {
1301                 err = GetLastError();
1302                 CloseHandle(h);
1303                 goto fail;
1304         }
1305         DEBUG("Closing \"%ls\"", path);
1306         if (!CloseHandle(h)) {
1307                 err = GetLastError();
1308                 goto fail;
1309         }
1310         goto out;
1311 fail:
1312         /* Only warn if setting timestamps failed; still return 0. */
1313         WARNING("Can't set timestamps on \"%ls\"", path);
1314         win32_error(err);
1315 out:
1316         return 0;
1317 }
1318
1319 #endif /* __WIN32__ */