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   1 /*
   2  * wimboot.c
   3  *
   4  * Support for creating WIMBoot pointer files.
   5  *
   6  * See http://technet.microsoft.com/en-us/library/dn594399.aspx for general
   7  * information about WIMBoot.
   8  *
   9  * Note that WIMBoot pointer files are actually implemented on top of the
  10  * Windows Overlay File System Filter (WOF).  See wof.h for more info.
  11  */
  12
  13 /*
  14  * Copyright (C) 2014 Eric Biggers
  15  *
  16  * This file is part of wimlib, a library for working with WIM files.
  17  *
  18  * wimlib is free software; you can redistribute it and/or modify it under the
  19  * terms of the GNU General Public License as published by the Free
  20  * Software Foundation; either version 3 of the License, or (at your option)
  21  * any later version.
  22  *
  23  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  24  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  25  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  26  * details.
  27  *
  28  * You should have received a copy of the GNU General Public License
  29  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  30  */
  31
  32
  33 #ifdef HAVE_CONFIG_H
  34 #  include "config.h"
  35 #endif
  36
  37 #include "wimlib/win32_common.h"
  38 #include "wimlib/win32.h"
  39 #include "wimlib/assert.h"
  40 #include "wimlib/error.h"
  41 #include "wimlib/lookup_table.h"
  42 #include "wimlib/util.h"
  43 #include "wimlib/wimboot.h"
  44 #include "wimlib/wof.h"
  45
  46 static HANDLE
  47 open_file(const wchar_t *device_name, DWORD desiredAccess)
  48 {
  49         return CreateFile(device_name, desiredAccess,
  50                           FILE_SHARE_VALID_FLAGS, NULL, OPEN_EXISTING,
  51                           FILE_FLAG_BACKUP_SEMANTICS, NULL);
  52 }
  53
  54 static BOOL
  55 query_device(HANDLE h, DWORD code, void *out, DWORD out_size)
  56 {
  57         DWORD bytes_returned;
  58         return DeviceIoControl(h, code, NULL, 0, out, out_size,
  59                                &bytes_returned, NULL);
  60 }
  61
  62 /*
  63  * Gets partition and drive information for the specified path.
  64  *
  65  * @path
  66  *      Absolute path which must begin with a drive letter.  For example, if the
  67  *      path is D:\install.wim, this function will query information about the
  68  *      D: volume.
  69  * @part_info_ret
  70  *      Partition info is returned here.
  71  * @drive_info_ret
  72  *      Drive info is returned here.  The contained partition info will not be
  73  *      valid.
  74  *
  75  * Returns 0 on success, or a positive error code on failure.
  76  */
  77 static int
  78 query_partition_and_disk_info(const wchar_t *path,
  79                               PARTITION_INFORMATION_EX *part_info_ret,
  80                               DRIVE_LAYOUT_INFORMATION_EX *drive_info_ret)
  81 {
  82         HANDLE h;
  83         wchar_t vol_name[] = L"\\\\.\\X:";
  84         wchar_t disk_name[] = L"\\\\?\\PhysicalDriveXXXXXXXXXX";
  85
  86         PARTITION_INFORMATION_EX part_info;
  87         size_t extents_size = sizeof(VOLUME_DISK_EXTENTS) + 4 * sizeof(DISK_EXTENT);
  88         VOLUME_DISK_EXTENTS *extents = alloca(extents_size);
  89         size_t drive_info_size = sizeof(DRIVE_LAYOUT_INFORMATION_EX) +
  90                                         8 * sizeof(PARTITION_INFORMATION_EX);
  91         DRIVE_LAYOUT_INFORMATION_EX *drive_info = alloca(drive_info_size);
  92
  93         wimlib_assert(path[0] != L'\0' && path[1] == L':');
  94
  95         *(wcschr(vol_name, L'X')) = path[0];
  96
  97         h = open_file(vol_name, GENERIC_READ);
  98         if (h == INVALID_HANDLE_VALUE) {
  99                 set_errno_from_GetLastError();
 100                 ERROR_WITH_ERRNO("\"%ls\": Can't open volume device", vol_name);
 101                 return WIMLIB_ERR_OPEN;
 102         }
 103
 104         if (!query_device(h, IOCTL_DISK_GET_PARTITION_INFO_EX,
 105                           &part_info, sizeof(part_info)))
 106         {
 107                 ERROR("\"%ls\": Can't get partition info (err=0x%08"PRIx32")",
 108                       vol_name, (u32)GetLastError());
 109                 CloseHandle(h);
 110                 return WIMLIB_ERR_READ;
 111         }
 112
 113         if (!query_device(h, IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS,
 114                           extents, extents_size))
 115         {
 116                 ERROR("\"%ls\": Can't get volume extent info (err=0x%08"PRIx32")",
 117                       vol_name, (u32)GetLastError());
 118                 CloseHandle(h);
 119                 return WIMLIB_ERR_READ;
 120         }
 121
 122         CloseHandle(h);
 123
 124         if (extents->NumberOfDiskExtents != 1) {
 125                 ERROR("\"%ls\": This volume has %"PRIu32" disk extents, "
 126                       "but this code is untested for more than 1",
 127                       vol_name, (u32)extents->NumberOfDiskExtents);
 128                 return WIMLIB_ERR_UNSUPPORTED;
 129         }
 130
 131         wsprintf(wcschr(disk_name, L'X'), L"%"PRIu32,
 132                  extents->Extents[0].DiskNumber);
 133
 134         h = open_file(disk_name, GENERIC_READ);
 135         if (h == INVALID_HANDLE_VALUE) {
 136                 set_errno_from_GetLastError();
 137                 ERROR_WITH_ERRNO("\"%ls\": Can't open disk device", disk_name);
 138                 return WIMLIB_ERR_OPEN;
 139         }
 140
 141         if (!query_device(h, IOCTL_DISK_GET_DRIVE_LAYOUT_EX,
 142                           drive_info, drive_info_size))
 143         {
 144                 ERROR("\"%ls\": Can't get disk info (err=0x%08"PRIx32")",
 145                       disk_name, (u32)GetLastError());
 146                 CloseHandle(h);
 147                 return WIMLIB_ERR_READ;
 148         }
 149
 150         CloseHandle(h);
 151
 152         if (drive_info->PartitionStyle != part_info.PartitionStyle) {
 153                 ERROR("\"%ls\", \"%ls\": Inconsistent partition table type!",
 154                       vol_name, disk_name);
 155                 return WIMLIB_ERR_UNSUPPORTED;
 156         }
 157
 158         if (part_info.PartitionStyle == PARTITION_STYLE_GPT) {
 159                 BUILD_BUG_ON(sizeof(part_info.Gpt.PartitionId) !=
 160                              sizeof(drive_info->Gpt.DiskId));
 161                 if (!memcmp(&part_info.Gpt.PartitionId,
 162                             &drive_info->Gpt.DiskId,
 163                             sizeof(drive_info->Gpt.DiskId)))
 164                 {
 165                         ERROR("\"%ls\", \"%ls\": Partition GUID is the "
 166                               "same as the disk GUID???", vol_name, disk_name);
 167                         return WIMLIB_ERR_UNSUPPORTED;
 168                 }
 169         }
 170
 171         if (part_info.PartitionStyle != PARTITION_STYLE_MBR &&
 172             part_info.PartitionStyle != PARTITION_STYLE_GPT)
 173         {
 174                 ERROR("\"%ls\": Unknown partition style 0x%08"PRIx32,
 175                       vol_name, (u32)part_info.PartitionStyle);
 176                 return WIMLIB_ERR_UNSUPPORTED;
 177         }
 178
 179         *part_info_ret = part_info;
 180         *drive_info_ret = *drive_info;
 181         return 0;
 182 }
 183
 184 /*
 185  * Allocate a new WIM data source ID.
 186  *
 187  * @old_hdr
 188  *      Previous WimOverlay.dat contents, or NULL if file did not exist.
 189  *
 190  * Returns the new data source ID.
 191  */
 192 static u64
 193 alloc_new_data_source_id(const struct WimOverlay_dat_header *old_hdr)
 194 {
 195         if (!old_hdr)
 196                 return 0;
 197
 198         for (u64 id = 0; ; id++) {
 199                 for (u32 i = 0; i < old_hdr->num_entries_1; i++)
 200                         if (id == old_hdr->entry_1s[i].data_source_id)
 201                                 goto next;
 202                 return id;
 203         next:
 204                 ;
 205         }
 206 }
 207
 208 /*
 209  * Calculate the size of WimOverlay.dat with one entry added.
 210  *
 211  * @old_hdr
 212  *      Previous WimOverlay.dat contents, or NULL if file did not exist.
 213  * @new_entry_2_size
 214  *      Size of entry_2 being added.
 215  * @size_ret
 216  *      Size will be returned here.
 217  *
 218  * Returns 0 on success, or WIMLIB_ERR_UNSUPPORTED if size overflows 32 bits.
 219  */
 220 static int
 221 calculate_wimoverlay_dat_size(const struct WimOverlay_dat_header *old_hdr,
 222                               u32 new_entry_2_size, u32 *size_ret)
 223 {
 224         u64 size_64;
 225         u32 size;
 226
 227         size_64 = sizeof(struct WimOverlay_dat_header);
 228         if (old_hdr) {
 229                 for (u32 i = 0; i < old_hdr->num_entries_1; i++) {
 230                         size_64 += sizeof(struct WimOverlay_dat_entry_1);
 231                         size_64 += old_hdr->entry_1s[i].entry_2_length;
 232                 }
 233         }
 234         size_64 += sizeof(struct WimOverlay_dat_entry_1);
 235         size_64 += new_entry_2_size;
 236
 237         size = size_64;
 238         if (size_64 != size)
 239                 return WIMLIB_ERR_UNSUPPORTED;
 240
 241         *size_ret = size;
 242         return 0;
 243 }
 244
 245 /*
 246  * Writes @size bytes of @contents to the named file @path.
 247  *
 248  * Returns 0 on success; WIMLIB_ERR_OPEN or WIMLIB_ERR_WRITE on failure.
 249  */
 250 static int
 251 write_wimoverlay_dat(const wchar_t *path, const void *contents, u32 size)
 252 {
 253         HANDLE h;
 254         DWORD bytes_written;
 255
 256         h = CreateFile(path, GENERIC_WRITE, 0, NULL,
 257                        CREATE_ALWAYS, FILE_FLAG_BACKUP_SEMANTICS, NULL);
 258         if (h == INVALID_HANDLE_VALUE) {
 259                 set_errno_from_GetLastError();
 260                 ERROR_WITH_ERRNO("\"%ls\": Can't open file for writing", path);
 261                 return WIMLIB_ERR_OPEN;
 262         }
 263
 264         if (!WriteFile(h, contents, size, &bytes_written, NULL) ||
 265             bytes_written != size)
 266         {
 267                 set_errno_from_GetLastError();
 268                 ERROR_WITH_ERRNO("\"%ls\": Can't write file", path);
 269                 CloseHandle(h);
 270                 return WIMLIB_ERR_WRITE;
 271         }
 272
 273         if (!CloseHandle(h)) {
 274                 set_errno_from_GetLastError();
 275                 ERROR_WITH_ERRNO("\"%ls\": Can't close handle", path);
 276                 return WIMLIB_ERR_WRITE;
 277         }
 278
 279         return 0;
 280 }
 281
 282 /*
 283  * Generates the contents of WimOverlay.dat in memory, with one entry added.
 284  *
 285  * @buf
 286  *      Buffer large enough to hold the new contents.
 287  * @old_hdr
 288  *      Old contents of WimOverlay.dat, or NULL if it did not exist.
 289  * @wim_path
 290  *      Absolute path to the WIM file.  It must begin with a drive letter; for
 291  *      example, D:\install.wim.
 292  * @wim_guid
 293  *      GUID of the WIM, from the WIM header.
 294  * @image
 295  *      Number of the image in the WIM to specify in the new entry.
 296  * @new_data_source_id
 297  *      Data source ID to use for the new entry.
 298  * @part_info
 299  *      Partition information for the WIM file.
 300  * @disk_info
 301  *      Disk information for the WIM file.
 302  * @new_entry_2_size
 303  *      Size, in bytes, of the new location information structure ('struct
 304  *      WimOverlay_dat_entry_2').
 305  *
 306  * Returns a pointer one past the last byte of @buf filled in.
 307  */
 308 static u8 *
 309 fill_in_wimoverlay_dat(u8 *buf,
 310                        const struct WimOverlay_dat_header *old_hdr,
 311                        const wchar_t *wim_path,
 312                        const u8 wim_guid[WIM_GUID_LEN],
 313                        int image,
 314                        u64 new_data_source_id,
 315                        const PARTITION_INFORMATION_EX *part_info,
 316                        const DRIVE_LAYOUT_INFORMATION_EX *disk_info,
 317                        u32 new_entry_2_size)
 318 {
 319         struct WimOverlay_dat_header *new_hdr;
 320         struct WimOverlay_dat_entry_1 *new_entry_1;
 321         struct WimOverlay_dat_entry_2 *new_entry_2;
 322         u32 entry_2_offset;
 323         u8 *p = buf;
 324
 325         new_hdr = (struct WimOverlay_dat_header *)p;
 326
 327         /* Fill in new header  */
 328         new_hdr->magic = WIMOVERLAY_DAT_MAGIC;
 329         new_hdr->wim_provider_version = WIM_PROVIDER_CURRENT_VERSION;
 330         new_hdr->unknown_0x08 = 0x00000028;
 331         new_hdr->num_entries_1 = (old_hdr ? old_hdr->num_entries_1 : 0) + 1;
 332         new_hdr->num_entries_2 = (old_hdr ? old_hdr->num_entries_2 : 0) + 1;
 333         new_hdr->unknown_0x14 = 0x00000000;
 334
 335         p += sizeof(struct WimOverlay_dat_header);
 336
 337         /* Copy WIM-specific information for old entries  */
 338         entry_2_offset = sizeof(struct WimOverlay_dat_header) +
 339                         (new_hdr->num_entries_1 * sizeof(struct WimOverlay_dat_entry_1));
 340         if (old_hdr) {
 341                 for (u32 i = 0; i < old_hdr->num_entries_1; i++) {
 342                         new_entry_1 = (struct WimOverlay_dat_entry_1 *)p;
 343
 344                         p = mempcpy(p, &old_hdr->entry_1s[i],
 345                                     sizeof(struct WimOverlay_dat_entry_1));
 346
 347                         new_entry_1->entry_2_offset = entry_2_offset;
 348                         entry_2_offset += new_entry_1->entry_2_length;
 349                 }
 350         }
 351
 352         /* Generate WIM-specific information for new entry  */
 353         new_entry_1 = (struct WimOverlay_dat_entry_1 *)p;
 354
 355         new_entry_1->data_source_id = new_data_source_id;
 356         new_entry_1->entry_2_offset = entry_2_offset;
 357         new_entry_1->entry_2_length = new_entry_2_size;
 358         new_entry_1->wim_type = WIM_BOOT_NOT_OS_WIM;
 359         new_entry_1->wim_index = image;
 360         BUILD_BUG_ON(sizeof(new_entry_1->guid) != WIM_GUID_LEN);
 361         memcpy(new_entry_1->guid, wim_guid, WIM_GUID_LEN);
 362
 363         p += sizeof(struct WimOverlay_dat_entry_1);
 364
 365         /* Copy WIM location information for old entries  */
 366         if (old_hdr) {
 367                 for (u32 i = 0; i < old_hdr->num_entries_1; i++) {
 368                         wimlib_assert(new_hdr->entry_1s[i].entry_2_offset == p - buf);
 369                         wimlib_assert(old_hdr->entry_1s[i].entry_2_length ==
 370                                       new_hdr->entry_1s[i].entry_2_length);
 371                         p = mempcpy(p,
 372                                     ((const u8 *)old_hdr + old_hdr->entry_1s[i].entry_2_offset),
 373                                     old_hdr->entry_1s[i].entry_2_length);
 374                 }
 375         }
 376
 377         /* Generate WIM location information for new entry  */
 378         new_entry_2 = (struct WimOverlay_dat_entry_2 *)p;
 379
 380         new_entry_2->unknown_0x00 = 0x00000000;
 381         new_entry_2->unknown_0x04 = 0x00000000;
 382         new_entry_2->entry_2_length = new_entry_2_size;
 383         new_entry_2->unknown_0x0C = 0x00000000;
 384         new_entry_2->unknown_0x10 = 0x00000005;
 385         new_entry_2->unknown_0x14 = 0x00000001;
 386         new_entry_2->inner_struct_size = new_entry_2_size - 0x14;
 387         new_entry_2->unknown_0x1C = 0x00000005;
 388         new_entry_2->unknown_0x20 = 0x00000006;
 389         new_entry_2->unknown_0x24 = 0x00000000;
 390         new_entry_2->unknown_0x28 = 0x00000048;
 391         new_entry_2->unknown_0x2C = 0x00000000;
 392         new_entry_2->unknown_0x40 = 0x00000000;
 393
 394         if (part_info->PartitionStyle == PARTITION_STYLE_MBR) {
 395                 new_entry_2->partition.mbr.part_start_offset = part_info->StartingOffset.QuadPart;
 396                 new_entry_2->partition.mbr.padding = 0;
 397                 new_entry_2->partition_table_type = WIMOVERLAY_PARTITION_TYPE_MBR;
 398                 new_entry_2->disk.mbr.disk_id = disk_info->Mbr.Signature;
 399                 new_entry_2->disk.mbr.padding[0] = 0x00000000;
 400                 new_entry_2->disk.mbr.padding[1] = 0x00000000;
 401                 new_entry_2->disk.mbr.padding[2] = 0x00000000;
 402         } else {
 403                 BUILD_BUG_ON(sizeof(new_entry_2->partition.gpt.part_unique_guid) !=
 404                              sizeof(part_info->Gpt.PartitionId));
 405                 memcpy(new_entry_2->partition.gpt.part_unique_guid,
 406                        &part_info->Gpt.PartitionId,
 407                        sizeof(part_info->Gpt.PartitionId));
 408                 new_entry_2->partition_table_type = WIMOVERLAY_PARTITION_TYPE_GPT;
 409
 410                 BUILD_BUG_ON(sizeof(new_entry_2->disk.gpt.disk_guid) !=
 411                              sizeof(disk_info->Gpt.DiskId));
 412                 memcpy(new_entry_2->disk.gpt.disk_guid,
 413                        &disk_info->Gpt.DiskId,
 414                        sizeof(disk_info->Gpt.DiskId));
 415
 416                 BUILD_BUG_ON(sizeof(new_entry_2->disk.gpt.disk_guid) !=
 417                              sizeof(new_entry_2->partition.gpt.part_unique_guid));
 418         }
 419         new_entry_2->unknown_0x58[0] = 0x00000000;
 420         new_entry_2->unknown_0x58[1] = 0x00000000;
 421         new_entry_2->unknown_0x58[2] = 0x00000000;
 422         new_entry_2->unknown_0x58[3] = 0x00000000;
 423
 424         wimlib_assert(wim_path[2] == L'\\');
 425         return mempcpy(new_entry_2->wim_file_name,
 426                        wim_path + 2,
 427                        new_entry_2_size - sizeof(struct WimOverlay_dat_entry_2));
 428 }
 429
 430 /*
 431  * Prepares the new contents of WimOverlay.dat in memory, with one entry added.
 432  *
 433  * @old_hdr
 434  *      Old contents of WimOverlay.dat, or NULL if it did not exist.
 435  * @wim_path
 436  *      Absolute path to the WIM file.  It must begin with a drive letter; for
 437  *      example, D:\install.wim.
 438  * @wim_guid
 439  *      GUID of the WIM, from the WIM header.
 440  * @image
 441  *      Number of the image in the WIM to specify in the new entry.
 442  * @new_contents_ret
 443  *      Location into which to return the new contents as a malloc()ed buffer on
 444  *      success.
 445  * @new_contents_size_ret
 446  *      Location into which to return the size, in bytes, of the new contents on
 447  *      success.
 448  * @new_data_source_id_ret
 449  *      Location into which to return the data source ID of the new entry on
 450  *      success.
 451  *
 452  * Returns 0 on success, or a positive error code on failure.
 453  */
 454 static int
 455 prepare_wimoverlay_dat(const struct WimOverlay_dat_header *old_hdr,
 456                        const wchar_t *wim_path,
 457                        const u8 wim_guid[WIM_GUID_LEN],
 458                        int image,
 459                        void **new_contents_ret,
 460                        u32 *new_contents_size_ret,
 461                        u64 *new_data_source_id_ret)
 462 {
 463         int ret;
 464         PARTITION_INFORMATION_EX part_info;
 465         DRIVE_LAYOUT_INFORMATION_EX disk_info;
 466         u64 new_data_source_id;
 467         u32 new_entry_2_size;
 468         u32 new_contents_size;
 469         u8 *buf;
 470         u8 *end;
 471
 472         ret = query_partition_and_disk_info(wim_path, &part_info, &disk_info);
 473         if (ret)
 474                 return ret;
 475
 476         new_data_source_id = alloc_new_data_source_id(old_hdr);
 477
 478         new_entry_2_size = sizeof(struct WimOverlay_dat_entry_2) +
 479                                 ((wcslen(wim_path) - 2 + 1) * sizeof(wchar_t));
 480         ret = calculate_wimoverlay_dat_size(old_hdr, new_entry_2_size,
 481                                             &new_contents_size);
 482         if (ret)
 483                 return ret;
 484
 485         buf = MALLOC(new_contents_size);
 486         if (!buf)
 487                 return WIMLIB_ERR_NOMEM;
 488
 489         end = fill_in_wimoverlay_dat(buf, old_hdr, wim_path, wim_guid, image,
 490                                      new_data_source_id,
 491                                      &part_info, &disk_info, new_entry_2_size);
 492
 493         wimlib_assert(end - buf == new_contents_size);
 494
 495         *new_contents_ret = buf;
 496         *new_contents_size_ret = new_contents_size;
 497         *new_data_source_id_ret = new_data_source_id;
 498         return 0;
 499 }
 500
 501 /*
 502  * Reads and validates a WimOverlay.dat file.
 503  *
 504  * @path
 505  *      Path to the WimOverlay.dat file, such as
 506  *      C:\System Volume Information\WimOverlay.dat
 507  * @contents_ret
 508  *      Location into which to return the contents as a malloc()ed buffer on
 509  *      success.  This can be cast to 'struct WimOverlay_dat_header', and its
 510  *      contents are guaranteed to be valid.  Alternatively, if the file does
 511  *      not exist, NULL will be returned here.
 512  *
 513  * Returns 0 on success, or a positive error code on failure.
 514  */
 515 static int
 516 read_wimoverlay_dat(const wchar_t *path, void **contents_ret)
 517 {
 518         HANDLE h;
 519         BY_HANDLE_FILE_INFORMATION info;
 520         int ret;
 521         void *contents;
 522         const struct WimOverlay_dat_header *hdr;
 523         DWORD bytes_read;
 524         bool already_retried = false;
 525
 526 retry:
 527         h = open_file(path, GENERIC_READ);
 528         if (h == INVALID_HANDLE_VALUE) {
 529                 DWORD err = GetLastError();
 530                 if (err == ERROR_FILE_NOT_FOUND) {
 531                         *contents_ret = NULL;
 532                         return 0;
 533                 }
 534                 if (err == ERROR_PATH_NOT_FOUND &&
 535                     func_RtlCreateSystemVolumeInformationFolder)
 536                 {
 537                         wchar_t volume_root_path[] = L"\\??\\X:\\";
 538
 539                         *(wcschr(volume_root_path, L'X')) = path[0];
 540
 541                         UNICODE_STRING str = {
 542                                 .Length = sizeof(volume_root_path) - sizeof(wchar_t),
 543                                 .MaximumLength = sizeof(volume_root_path),
 544                                 .Buffer = volume_root_path,
 545                         };
 546                         NTSTATUS status;
 547                         DWORD err2;
 548
 549                         status = (*func_RtlCreateSystemVolumeInformationFolder)(&str);
 550
 551                         err2 = (*func_RtlNtStatusToDosError)(status);
 552                         if (err2 == ERROR_SUCCESS) {
 553                                 if (!already_retried) {
 554                                         already_retried = true;
 555                                         goto retry;
 556                                 }
 557                         } else {
 558                                 err = err2;
 559                         }
 560                 }
 561                 set_errno_from_win32_error(err);
 562                 ERROR_WITH_ERRNO("\"%ls\": Can't open for reading", path);
 563                 return WIMLIB_ERR_OPEN;
 564         }
 565         if (!GetFileInformationByHandle(h, &info)) {
 566                 set_errno_from_GetLastError();
 567                 ERROR_WITH_ERRNO("\"%ls\": Can't query metadata", path);
 568                 CloseHandle(h);
 569                 return WIMLIB_ERR_STAT;
 570         }
 571
 572         contents = NULL;
 573         if (!info.nFileSizeHigh)
 574                 contents = MALLOC(info.nFileSizeLow);
 575         if (!contents) {
 576                 ERROR("\"%ls\": File is too large to fit into memory", path);
 577                 CloseHandle(h);
 578                 return WIMLIB_ERR_NOMEM;
 579         }
 580
 581         if (!ReadFile(h, contents, info.nFileSizeLow, &bytes_read, NULL) ||
 582             bytes_read != info.nFileSizeLow)
 583         {
 584                 set_errno_from_GetLastError();
 585                 ERROR_WITH_ERRNO("\"%ls\": Can't read data", path);
 586                 CloseHandle(h);
 587                 ret = WIMLIB_ERR_READ;
 588                 goto out_free_contents;
 589         }
 590
 591         CloseHandle(h);
 592
 593         if (info.nFileSizeLow < sizeof(struct WimOverlay_dat_header)) {
 594                 ERROR("\"%ls\": File is unexpectedly small (only %"PRIu32" bytes)",
 595                       path, (u32)info.nFileSizeLow);
 596                 ret = WIMLIB_ERR_UNSUPPORTED;
 597                 goto out_free_contents;
 598         }
 599
 600         hdr = (const struct WimOverlay_dat_header *)contents;
 601
 602         if (hdr->magic != WIMOVERLAY_DAT_MAGIC ||
 603             hdr->wim_provider_version != WIM_PROVIDER_CURRENT_VERSION ||
 604             hdr->unknown_0x08 != 0x00000028 ||
 605             (hdr->num_entries_1 != hdr->num_entries_2) ||
 606             hdr->unknown_0x14 != 0x00000000)
 607         {
 608                 ERROR("\"%ls\": Header contains unexpected data:", path);
 609                 if (wimlib_print_errors) {
 610                         print_byte_field((const u8 *)hdr,
 611                                          sizeof(struct WimOverlay_dat_header),
 612                                          stderr);
 613                         fputc('\n', stderr);
 614                 }
 615                 ret = WIMLIB_ERR_UNSUPPORTED;
 616                 goto out_free_contents;
 617         }
 618
 619         if ((u64)hdr->num_entries_1 * sizeof(struct WimOverlay_dat_entry_1) >
 620             info.nFileSizeLow - sizeof(struct WimOverlay_dat_header))
 621         {
 622                 ERROR("\"%ls\": File is unexpectedly small "
 623                       "(only %"PRIu32" bytes, but has %"PRIu32" entries)",
 624                       path, (u32)info.nFileSizeLow, hdr->num_entries_1);
 625                 ret = WIMLIB_ERR_UNSUPPORTED;
 626                 goto out_free_contents;
 627         }
 628
 629         for (u32 i = 0; i < hdr->num_entries_1; i++) {
 630                 const struct WimOverlay_dat_entry_1 *entry_1;
 631                 const struct WimOverlay_dat_entry_2 *entry_2;
 632                 u32 wim_file_name_length;
 633
 634                 entry_1 = &hdr->entry_1s[i];
 635
 636                 if (((u64)entry_1->entry_2_offset +
 637                      (u64)entry_1->entry_2_length) >
 638                     info.nFileSizeLow)
 639                 {
 640                         ERROR("\"%ls\": entry %"PRIu32" (2) "
 641                               "(data source ID 0x%016"PRIx64") "
 642                               "overflows file",
 643                               path, i, entry_1->data_source_id);
 644                         ret = WIMLIB_ERR_UNSUPPORTED;
 645                         goto out_free_contents;
 646                 }
 647                 if (entry_1->entry_2_length < sizeof(struct WimOverlay_dat_entry_2)) {
 648                         ERROR("\"%ls\": entry %"PRIu32" (2) "
 649                               "(data source ID 0x%016"PRIx64") "
 650                               "is too short",
 651                               path, i, entry_1->data_source_id);
 652                         ret = WIMLIB_ERR_UNSUPPORTED;
 653                         goto out_free_contents;
 654                 }
 655
 656                 if (entry_1->entry_2_offset % 2 != 0) {
 657                         ERROR("\"%ls\": entry %"PRIu32" (2) "
 658                               "(data source ID 0x%016"PRIx64") "
 659                               "is misaligned",
 660                               path, i, entry_1->data_source_id);
 661                         ret = WIMLIB_ERR_UNSUPPORTED;
 662                         goto out_free_contents;
 663                 }
 664
 665                 entry_2 = (const struct WimOverlay_dat_entry_2 *)
 666                                 ((const u8 *)hdr + entry_1->entry_2_offset);
 667
 668                 wim_file_name_length = entry_1->entry_2_length -
 669                                         sizeof(struct WimOverlay_dat_entry_2);
 670                 if ((wim_file_name_length < 2 * sizeof(wchar_t)) ||
 671                     (wim_file_name_length % sizeof(wchar_t) != 0) ||
 672                     (wmemchr(entry_2->wim_file_name, L'\0',
 673                              wim_file_name_length / sizeof(wchar_t))
 674                      != &entry_2->wim_file_name[wim_file_name_length /
 675                                                 sizeof(wchar_t) - 1]))
 676                 {
 677                         ERROR("\"%ls\": entry %"PRIu32" (2) "
 678                               "(data source ID 0x%016"PRIx64") "
 679                               "has invalid WIM file name",
 680                               path, i, entry_1->data_source_id);
 681                         if (wimlib_print_errors) {
 682                                 print_byte_field((const u8 *)entry_2->wim_file_name,
 683                                                  wim_file_name_length, stderr);
 684                                 fputc('\n', stderr);
 685                         }
 686                         ret = WIMLIB_ERR_UNSUPPORTED;
 687                         goto out_free_contents;
 688                 }
 689
 690                 if (entry_2->unknown_0x00 != 0x00000000 ||
 691                     entry_2->unknown_0x04 != 0x00000000 ||
 692                     entry_2->unknown_0x0C != 0x00000000 ||
 693                     entry_2->entry_2_length != entry_1->entry_2_length ||
 694                     entry_2->unknown_0x10 != 0x00000005 ||
 695                     entry_2->unknown_0x14 != 0x00000001 ||
 696                     entry_2->inner_struct_size != entry_1->entry_2_length - 0x14 ||
 697                     entry_2->unknown_0x1C != 0x00000005 ||
 698                     entry_2->unknown_0x20 != 0x00000006 ||
 699                     entry_2->unknown_0x24 != 0x00000000 ||
 700                     entry_2->unknown_0x28 != 0x00000048 ||
 701                     entry_2->unknown_0x2C != 0x00000000 ||
 702                     entry_2->unknown_0x40 != 0x00000000 ||
 703                     (entry_2->partition_table_type != WIMOVERLAY_PARTITION_TYPE_GPT &&
 704                      entry_2->partition_table_type != WIMOVERLAY_PARTITION_TYPE_MBR) ||
 705                     (entry_2->partition_table_type == WIMOVERLAY_PARTITION_TYPE_MBR &&
 706                      entry_2->partition.mbr.padding != 0) ||
 707                     (entry_2->partition_table_type == WIMOVERLAY_PARTITION_TYPE_GPT &&
 708                      entry_2->partition.mbr.padding == 0) ||
 709                     entry_2->unknown_0x58[0] != 0x00000000 ||
 710                     entry_2->unknown_0x58[1] != 0x00000000 ||
 711                     entry_2->unknown_0x58[2] != 0x00000000 ||
 712                     entry_2->unknown_0x58[3] != 0x00000000)
 713                 {
 714                         ERROR("\"%ls\": entry %"PRIu32" (2) "
 715                               "(data source ID 0x%016"PRIx64") "
 716                               "contains unexpected data!",
 717                               path, i, entry_1->data_source_id);
 718                         if (wimlib_print_errors) {
 719                                 print_byte_field((const u8 *)entry_2,
 720                                                  entry_1->entry_2_length,
 721                                                  stderr);
 722                                 fputc('\n', stderr);
 723                         }
 724                         ret = WIMLIB_ERR_UNSUPPORTED;
 725                         goto out_free_contents;
 726                 }
 727         }
 728
 729         *contents_ret = contents;
 730         return 0;
 731
 732 out_free_contents:
 733         FREE(contents);
 734         return ret;
 735 }
 736
 737 /*
 738  * Update WimOverlay.dat manually in order to add a WIM data source to the
 739  * target volume.
 740  *
 741  * THIS CODE IS EXPERIMENTAL AS I HAD TO REVERSE ENGINEER THE FILE FORMAT!
 742  *
 743  * @path
 744  *      Target drive.  Must be a letter followed by a colon (e.g. D:).
 745  * @wim_path
 746  *      Absolute path to the WIM file.  It must begin with a drive letter; for
 747  *      example, D:\install.wim.
 748  * @wim_guid
 749  *      GUID of the WIM, from the WIM header.
 750  * @image
 751  *      Number of the image in the WIM to specify in the new entry.
 752  * @data_source_id_ret
 753  *      On success, the allocated data source ID is returned here.
 754  */
 755 static int
 756 update_wimoverlay_manually(const wchar_t *drive, const wchar_t *wim_path,
 757                            const u8 wim_guid[WIM_GUID_LEN],
 758                            int image, u64 *data_source_id_ret)
 759 {
 760         wchar_t path_main[] = L"A:\\System Volume Information\\WimOverlay.dat";
 761         wchar_t path_backup[] = L"A:\\System Volume Information\\WimOverlay.backup";
 762         wchar_t path_wimlib_backup[] = L"A:\\System Volume Information\\WimOverlay.wimlib_backup";
 763         wchar_t path_new[] = L"A:\\System Volume Information\\WimOverlay.wimlib_new";
 764         void *old_contents;
 765         void *new_contents;
 766         u32 new_contents_size;
 767         u64 new_data_source_id;
 768         int ret;
 769
 770         wimlib_assert(drive[0] != L'\0' &&
 771                       drive[1] == L':' &&
 772                       drive[2] == L'\0');
 773
 774         path_main[0]          = drive[0];
 775         path_backup[0]        = drive[0];
 776         path_wimlib_backup[0] = drive[0];
 777         path_new[0]           = drive[0];
 778
 779         ret = read_wimoverlay_dat(path_main, &old_contents);
 780         if (ret)
 781                 goto out;
 782
 783         ret = prepare_wimoverlay_dat(old_contents, wim_path, wim_guid, image,
 784                                      &new_contents, &new_contents_size,
 785                                      &new_data_source_id);
 786         FREE(old_contents);
 787         if (ret)
 788                 goto out;
 789
 790         /* Write WimOverlay.wimlib_new  */
 791         ret = write_wimoverlay_dat(path_new,
 792                                    new_contents, new_contents_size);
 793         if (ret)
 794                 goto out_free_new_contents;
 795
 796         /* Write WimOverlay.backup  */
 797         ret = write_wimoverlay_dat(path_backup,
 798                                    new_contents, new_contents_size);
 799         if (ret)
 800                 goto out_free_new_contents;
 801
 802         if (old_contents) {
 803                 /* Rename WimOverlay.dat => WimOverlay.wimlib_backup  */
 804                 ret = win32_rename_replacement(path_main, path_wimlib_backup);
 805                 if (ret) {
 806                         ERROR_WITH_ERRNO("Can't rename \"%ls\" => \"%ls\"",
 807                                          path_main, path_wimlib_backup);
 808                         goto out_free_new_contents;
 809                 }
 810         }
 811
 812         /* Rename WimOverlay.wimlib_new => WimOverlay.dat  */
 813         ret = win32_rename_replacement(path_new, path_main);
 814         if (ret) {
 815                 ERROR_WITH_ERRNO("Can't rename \"%ls\" => \"%ls\"",
 816                                  path_new, path_main);
 817         }
 818 out_free_new_contents:
 819         FREE(new_contents);
 820 out:
 821         if (ret == WIMLIB_ERR_UNSUPPORTED) {
 822                 ERROR("Please report to developer ("PACKAGE_BUGREPORT").\n"
 823                       "        If possible send the file \"%ls\".\n\n", path_main);
 824         }
 825         if (ret == 0)
 826                 *data_source_id_ret = new_data_source_id;
 827         return ret;
 828 }
 829
 830 static int
 831 win32_get_drive_path(const wchar_t *file_path, wchar_t drive_path[7])
 832 {
 833         tchar *file_abspath;
 834
 835         file_abspath = realpath(file_path, NULL);
 836         if (!file_abspath)
 837                 return WIMLIB_ERR_NOMEM;
 838
 839         if (file_abspath[0] == L'\0' || file_abspath[1] != L':') {
 840                 ERROR("\"%ls\": Path format not recognized", file_abspath);
 841                 FREE(file_abspath);
 842                 return WIMLIB_ERR_UNSUPPORTED;
 843         }
 844
 845         wsprintf(drive_path, L"\\\\.\\%lc:", file_abspath[0]);
 846         FREE(file_abspath);
 847         return 0;
 848 }
 849
 850 /* Try to attach an instance of the Windows Overlay File System Filter Driver to
 851  * the specified drive (such as C:)  */
 852 static bool
 853 try_to_attach_wof(const wchar_t *drive)
 854 {
 855         HMODULE fltlib;
 856         bool retval = false;
 857
 858         /* Use FilterAttach() from Fltlib.dll.  */
 859
 860         fltlib = LoadLibrary(L"Fltlib.dll");
 861
 862         if (!fltlib) {
 863                 WARNING("Failed to load Fltlib.dll");
 864                 return retval;
 865         }
 866
 867         HRESULT (WINAPI *func_FilterAttach)(LPCWSTR lpFilterName,
 868                                             LPCWSTR lpVolumeName,
 869                                             LPCWSTR lpInstanceName,
 870                                             DWORD dwCreatedInstanceNameLength,
 871                                             LPWSTR lpCreatedInstanceName);
 872
 873         func_FilterAttach = (void *)GetProcAddress(fltlib, "FilterAttach");
 874
 875         if (func_FilterAttach) {
 876                 HRESULT res;
 877
 878                 res = (*func_FilterAttach)(L"WoF", drive, NULL, 0, NULL);
 879
 880                 if (res == S_OK)
 881                         retval = true;
 882         } else {
 883                 WARNING("FilterAttach() does not exist in Fltlib.dll");
 884         }
 885
 886         FreeLibrary(fltlib);
 887
 888         return retval;
 889 }
 890
 891 /*
 892  * Allocate a WOF data source ID for a WIM file.
 893  *
 894  * @wim_path
 895  *      Absolute path to the WIM file.  This must include a drive letter and use
 896  *      backslash path separators.
 897  * @wim_guid
 898  *      GUID of the WIM, from the WIM header.
 899  * @image
 900  *      Number of the image in the WIM being applied.
 901  * @target
 902  *      Path to the target directory.
 903  * @data_source_id_ret
 904  *      On success, an identifier for the backing WIM file will be returned
 905  *      here.
 906  *
 907  * Returns 0 on success, or a positive error code on failure.
 908  */
 909 int
 910 wimboot_alloc_data_source_id(const wchar_t *wim_path,
 911                              const u8 wim_guid[WIM_GUID_LEN],
 912                              int image, const wchar_t *target,
 913                              u64 *data_source_id_ret, bool *wof_running_ret)
 914 {
 915         tchar drive_path[7];
 916         size_t wim_path_nchars;
 917         size_t wim_file_name_length;
 918         void *in;
 919         size_t insize;
 920         struct wof_external_info *wof_info;
 921         struct wim_provider_add_overlay_input *wim_info;
 922         HANDLE h;
 923         u64 data_source_id;
 924         DWORD bytes_returned;
 925         int ret;
 926         const wchar_t *prefix = L"\\??\\";
 927         const size_t prefix_nchars = 4;
 928         bool tried_to_attach_wof = false;
 929
 930         ret = win32_get_drive_path(target, drive_path);
 931         if (ret)
 932                 return ret;
 933
 934         wimlib_assert(!wcschr(wim_path, L'/'));
 935         wimlib_assert(wim_path[0] != L'\0' && wim_path[1] == L':');
 936
 937         wim_path_nchars = wcslen(wim_path);
 938         wim_file_name_length = sizeof(wchar_t) *
 939                                (wim_path_nchars + prefix_nchars);
 940
 941         insize = sizeof(struct wof_external_info) +
 942                  sizeof(struct wim_provider_add_overlay_input) +
 943                  wim_file_name_length;
 944
 945         in = MALLOC(insize);
 946         if (!in) {
 947                 ret = WIMLIB_ERR_NOMEM;
 948                 goto out;
 949         }
 950
 951         wof_info = (struct wof_external_info *)in;
 952         wof_info->version = WOF_CURRENT_VERSION;
 953         wof_info->provider = WOF_PROVIDER_WIM;
 954
 955         wim_info = (struct wim_provider_add_overlay_input *)(wof_info + 1);
 956         wim_info->wim_type = WIM_BOOT_NOT_OS_WIM;
 957         wim_info->wim_index = image;
 958         wim_info->wim_file_name_offset = offsetof(struct wim_provider_add_overlay_input,
 959                                                   wim_file_name);
 960         wim_info->wim_file_name_length = wim_file_name_length;
 961         wmemcpy(&wim_info->wim_file_name[0], prefix, prefix_nchars);
 962         wmemcpy(&wim_info->wim_file_name[prefix_nchars], wim_path, wim_path_nchars);
 963
 964 retry_ioctl:
 965         h = open_file(drive_path, GENERIC_WRITE);
 966
 967         if (h == INVALID_HANDLE_VALUE) {
 968                 set_errno_from_GetLastError();
 969                 ERROR_WITH_ERRNO("Failed to open \"%ls\"", drive_path + 4);
 970                 ret = WIMLIB_ERR_OPEN;
 971                 goto out_free_in;
 972         }
 973
 974         if (!DeviceIoControl(h, FSCTL_ADD_OVERLAY,
 975                              in, insize,
 976                              &data_source_id, sizeof(data_source_id),
 977                              &bytes_returned, NULL))
 978         {
 979                 DWORD err = GetLastError();
 980                 if (err == ERROR_INVALID_FUNCTION) {
 981                         if (!tried_to_attach_wof) {
 982                                 CloseHandle(h);
 983                                 h = INVALID_HANDLE_VALUE;
 984                                 tried_to_attach_wof = true;
 985                                 if (try_to_attach_wof(drive_path + 4))
 986                                         goto retry_ioctl;
 987                         }
 988                         ret = WIMLIB_ERR_UNSUPPORTED;
 989                         goto out_close_handle;
 990                 } else {
 991                         set_errno_from_win32_error(err);
 992                         ERROR_WITH_ERRNO("Failed to add overlay source \"%ls\" "
 993                                          "to volume \"%ls\" (err=0x%08"PRIx32")",
 994                                          wim_path, drive_path + 4, (u32)err);
 995                         ret = WIMLIB_ERR_WIMBOOT;
 996                         goto out_close_handle;
 997                 }
 998         }
 999
1000         if (bytes_returned != sizeof(data_source_id)) {
1001                 set_errno_from_win32_error(ERROR_INVALID_DATA);
1002                 ret = WIMLIB_ERR_WIMBOOT;
1003                 ERROR("Unexpected result size when adding "
1004                       "overlay source \"%ls\" to volume \"%ls\"",
1005                       wim_path, drive_path + 4);
1006                 goto out_close_handle;
1007         }
1008
1009         *wof_running_ret = true;
1010         *data_source_id_ret = data_source_id;
1011         ret = 0;
1012
1013 out_close_handle:
1014         CloseHandle(h);
1015 out_free_in:
1016         FREE(in);
1017 out:
1018         if (ret == WIMLIB_ERR_UNSUPPORTED) {
1019         #if 0
1020                 WARNING(
1021                 "The version of Windows you are running does not appear to support\n"
1022                 "        the Windows Overlay File System Filter Driver.  This is normally\n"
1023                 "        available on Windows 8.1 Update 1 or later.  Therefore, wimlib\n"
1024                 "        will attempt to update the WimOverlay.dat file directly.\n");
1025         #else
1026                 WARNING("WOF driver is not available; updating WimOverlay.dat directly.");
1027         #endif
1028                 ret = update_wimoverlay_manually(drive_path + 4, wim_path,
1029                                                  wim_guid, image,
1030                                                  data_source_id_ret);
1031                 *wof_running_ret = false;
1032         }
1033         return ret;
1034 }
1035
1036
1037 /*
1038  * Set WIMBoot information on the specified file.
1039  *
1040  * This turns it into a reparse point that redirects accesses to it, to the
1041  * corresponding resource in the WIM archive.
1042  *
1043  * @attr
1044  *      Object attributes that specify the path to the file.
1045  * @printable_name
1046  *      Printable representation of the path encoded in @attr.
1047  * @lte
1048  *      Unnamed data stream of the file.
1049  * @data_source_id
1050  *      Allocated identifier for the WIM data source on the destination volume.
1051  * @lookup_table_hash
1052  *      SHA-1 message digest of the WIM's lookup table.
1053  * @wof_running
1054  *      %true if the WOF driver appears to be available and working; %false if
1055  *      not.
1056  *
1057  * Returns 0 on success, or a positive error code on failure.
1058  */
1059 int
1060 wimboot_set_pointer(OBJECT_ATTRIBUTES *attr,
1061                     const wchar_t *printable_name,
1062                     const struct wim_lookup_table_entry *lte,
1063                     u64 data_source_id,
1064                     const u8 lookup_table_hash[SHA1_HASH_SIZE],
1065                     bool wof_running)
1066 {
1067         int ret;
1068         HANDLE h = NULL;
1069         NTSTATUS status;
1070         IO_STATUS_BLOCK iosb;
1071         DWORD bytes_returned;
1072         DWORD err;
1073
1074         status = (*func_NtOpenFile)(&h, GENERIC_WRITE | SYNCHRONIZE, attr,
1075                                     &iosb, FILE_SHARE_VALID_FLAGS,
1076                                     FILE_OPEN_FOR_BACKUP_INTENT |
1077                                         FILE_OPEN_REPARSE_POINT |
1078                                         FILE_SYNCHRONOUS_IO_NONALERT);
1079         if (!NT_SUCCESS(status)) {
1080                 SetLastError((*func_RtlNtStatusToDosError)(status));
1081                 goto fail;
1082         }
1083
1084         if (wof_running) {
1085                 /* The WOF driver is running.  We can create the reparse point
1086                  * using FSCTL_SET_EXTERNAL_BACKING.  */
1087
1088                 struct {
1089                         struct wof_external_info wof_info;
1090                         struct wim_provider_external_info wim_info;
1091                 } in;
1092
1093                 in.wof_info.version = WOF_CURRENT_VERSION;
1094                 in.wof_info.provider = WOF_PROVIDER_WIM;
1095
1096                 in.wim_info.version = WIM_PROVIDER_CURRENT_VERSION;
1097                 in.wim_info.flags = 0;
1098                 in.wim_info.data_source_id = data_source_id;
1099                 copy_hash(in.wim_info.resource_hash, lte->hash);
1100
1101                 /* lookup_table_hash is not necessary  */
1102
1103                 if (!DeviceIoControl(h, FSCTL_SET_EXTERNAL_BACKING,
1104                                      &in, sizeof(in), NULL, 0,
1105                                      &bytes_returned, NULL))
1106                         goto fail;
1107         } else {
1108
1109                 /* The WOF driver is running.  We need to create the reparse
1110                  * point manually.  */
1111
1112                 struct {
1113                         struct {
1114                                 le32 rptag;
1115                                 le16 rpdatalen;
1116                                 le16 rpreserved;
1117                         } hdr;
1118                         struct wof_external_info wof_info;
1119                         struct wim_provider_rpdata wim_info;
1120                 } in;
1121
1122                 BUILD_BUG_ON(sizeof(in) != 8 +
1123                              sizeof(struct wof_external_info) +
1124                              sizeof(struct wim_provider_rpdata));
1125
1126                 in.hdr.rptag = WIMLIB_REPARSE_TAG_WOF;
1127                 in.hdr.rpdatalen = sizeof(in) - sizeof(in.hdr);
1128                 in.hdr.rpreserved = 0;
1129
1130                 in.wof_info.version = WOF_CURRENT_VERSION;
1131                 in.wof_info.provider = WOF_PROVIDER_WIM;
1132
1133                 in.wim_info.version = 2;
1134                 in.wim_info.flags = 0;
1135                 in.wim_info.data_source_id = data_source_id;
1136                 copy_hash(in.wim_info.resource_hash, lte->hash);
1137                 copy_hash(in.wim_info.wim_lookup_table_hash, lookup_table_hash);
1138                 in.wim_info.stream_uncompressed_size = lte->size;
1139                 in.wim_info.stream_compressed_size = lte->rspec->size_in_wim;
1140                 in.wim_info.stream_offset_in_wim = lte->rspec->offset_in_wim;
1141
1142                 if (!DeviceIoControl(h, FSCTL_SET_REPARSE_POINT,
1143                                      &in, sizeof(in), NULL, 0, &bytes_returned, NULL))
1144                         goto fail;
1145
1146                 /* We also need to create an unnamed data stream of the correct
1147                  * size.  Otherwise the file shows up as zero length.  It can be
1148                  * a sparse stream containing all zeroes; its contents
1149                  * are unimportant.  */
1150                 if (!DeviceIoControl(h, FSCTL_SET_SPARSE, NULL, 0, NULL, 0,
1151                                      &bytes_returned, NULL))
1152                         goto fail;
1153
1154                 if (!SetFilePointerEx(h,
1155                                       (LARGE_INTEGER){ .QuadPart = lte->size},
1156                                       NULL, FILE_BEGIN))
1157                         goto fail;
1158
1159                 if (!SetEndOfFile(h))
1160                         goto fail;
1161         }
1162
1163         ret = 0;
1164         goto out;
1165
1166 fail:
1167         err = GetLastError();
1168         set_errno_from_win32_error(err);
1169         ERROR_WITH_ERRNO("\"%ls\": Couldn't set WIMBoot pointer data "
1170                          "(err=%"PRIu32")", printable_name, (u32)err);
1171         ret = WIMLIB_ERR_WIMBOOT;
1172 out:
1173         if (h)
1174                 (*func_NtClose)(h);
1175         return ret;
1176
1177 }