wimlib.net Git - wimlib/blob - src/win32_apply.c

   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 #ifdef HAVE_CONFIG_H
  27 #  include "config.h"
  28 #endif
  29
  30 #include <aclapi.h> /* for SetSecurityInfo() */
  31
  32 #include "wimlib/win32_common.h"
  33
  34 #include "wimlib/apply.h"
  35 #include "wimlib/dentry.h"
  36 #include "wimlib/endianness.h"
  37 #include "wimlib/error.h"
  38 #include "wimlib/lookup_table.h"
  39 #include "wimlib/metadata.h"
  40 #include "wimlib/reparse.h"
  41 #include "wimlib/security.h"
  42
  43 #define MAX_CREATE_HARD_LINK_WARNINGS 5
  44 #define MAX_CREATE_SOFT_LINK_WARNINGS 5
  45
  46 #define MAX_SET_SD_ACCESS_DENIED_WARNINGS 1
  47 #define MAX_SET_SACL_PRIV_NOTHELD_WARNINGS 1
  48
  49 static const wchar_t *apply_access_denied_msg =
  50 L"If you are not running this program as the administrator, you may\n"
  51  "          need to do so, so that all data and metadata can be extracted\n"
  52  "          exactly as the origignal copy.  However, if you do not care that\n"
  53  "          the security descriptors are extracted correctly, you could run\n"
  54  "          `wimlib-imagex apply' with the --no-acls flag instead.\n"
  55  ;
  56
  57
  58 static int
  59 win32_extract_try_rpfix(u8 *rpbuf,
  60                         u16 *rpbuflen_p,
  61                         const wchar_t *extract_root_realpath,
  62                         unsigned extract_root_realpath_nchars)
  63 {
  64         struct reparse_data rpdata;
  65         wchar_t *target;
  66         size_t target_nchars;
  67         size_t stripped_nchars;
  68         wchar_t *stripped_target;
  69         wchar_t stripped_target_nchars;
  70         int ret;
  71
  72         utf16lechar *new_target;
  73         utf16lechar *new_print_name;
  74         size_t new_target_nchars;
  75         size_t new_print_name_nchars;
  76         utf16lechar *p;
  77
  78         ret = parse_reparse_data(rpbuf, *rpbuflen_p, &rpdata);
  79         if (ret)
  80                 return ret;
  81
  82         if (extract_root_realpath[0] == L'\0' ||
  83             extract_root_realpath[1] != L':' ||
  84             extract_root_realpath[2] != L'\\')
  85         {
  86                 ERROR("Can't understand full path format \"%ls\".  "
  87                       "Try turning reparse point fixups off...",
  88                       extract_root_realpath);
  89                 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
  90         }
  91
  92         ret = parse_substitute_name(rpdata.substitute_name,
  93                                     rpdata.substitute_name_nbytes,
  94                                     rpdata.rptag);
  95         if (ret < 0)
  96                 return 0;
  97         stripped_nchars = ret;
  98         target = rpdata.substitute_name;
  99         target_nchars = rpdata.substitute_name_nbytes / sizeof(utf16lechar);
 100         stripped_target = target + stripped_nchars;
 101         stripped_target_nchars = target_nchars - stripped_nchars;
 102
 103         new_target = alloca((6 + extract_root_realpath_nchars +
 104                              stripped_target_nchars) * sizeof(utf16lechar));
 105
 106         p = new_target;
 107         if (stripped_nchars == 6) {
 108                 /* Include \??\ prefix if it was present before */
 109                 p = wmempcpy(p, L"\\??\\", 4);
 110         }
 111
 112         /* Print name excludes the \??\ if present. */
 113         new_print_name = p;
 114         if (stripped_nchars != 0) {
 115                 /* Get drive letter from real path to extract root, if a drive
 116                  * letter was present before. */
 117                 *p++ = extract_root_realpath[0];
 118                 *p++ = extract_root_realpath[1];
 119         }
 120         /* Copy the rest of the extract root */
 121         p = wmempcpy(p, extract_root_realpath + 2, extract_root_realpath_nchars - 2);
 122
 123         /* Append the stripped target */
 124         p = wmempcpy(p, stripped_target, stripped_target_nchars);
 125         new_target_nchars = p - new_target;
 126         new_print_name_nchars = p - new_print_name;
 127
 128         if (new_target_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE ||
 129             new_print_name_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE)
 130         {
 131                 ERROR("Path names too long to do reparse point fixup!");
 132                 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
 133         }
 134         rpdata.substitute_name = new_target;
 135         rpdata.substitute_name_nbytes = new_target_nchars * sizeof(utf16lechar);
 136         rpdata.print_name = new_print_name;
 137         rpdata.print_name_nbytes = new_print_name_nchars * sizeof(utf16lechar);
 138         return make_reparse_buffer(&rpdata, rpbuf, rpbuflen_p);
 139 }
 140
 141 /* Wrapper around the FSCTL_SET_REPARSE_POINT ioctl to set the reparse data on
 142  * an extracted reparse point. */
 143 static int
 144 win32_set_reparse_data(HANDLE h,
 145                        const struct wim_inode *inode,
 146                        const struct wim_lookup_table_entry *lte,
 147                        const wchar_t *path,
 148                        struct apply_args *args)
 149 {
 150         int ret;
 151         u8 rpbuf[REPARSE_POINT_MAX_SIZE] _aligned_attribute(8);
 152         DWORD bytesReturned;
 153         u16 rpbuflen;
 154
 155         DEBUG("Setting reparse data on \"%ls\"", path);
 156
 157         ret = wim_inode_get_reparse_data(inode, rpbuf, &rpbuflen);
 158         if (ret)
 159                 return ret;
 160
 161         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX &&
 162             (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
 163              inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT) &&
 164             !inode->i_not_rpfixed)
 165         {
 166                 ret = win32_extract_try_rpfix(rpbuf,
 167                                               &rpbuflen,
 168                                               args->target_realpath,
 169                                               args->target_realpath_len);
 170                 if (ret)
 171                         return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
 172         }
 173
 174         /* Set the reparse data on the open file using the
 175          * FSCTL_SET_REPARSE_POINT ioctl.
 176          *
 177          * There are contradictions in Microsoft's documentation for this:
 178          *
 179          * "If hDevice was opened without specifying FILE_FLAG_OVERLAPPED,
 180          * lpOverlapped is ignored."
 181          *
 182          * --- So setting lpOverlapped to NULL is okay since it's ignored.
 183          *
 184          * "If lpOverlapped is NULL, lpBytesReturned cannot be NULL. Even when an
 185          * operation returns no output data and lpOutBuffer is NULL,
 186          * DeviceIoControl makes use of lpBytesReturned. After such an
 187          * operation, the value of lpBytesReturned is meaningless."
 188          *
 189          * --- So lpOverlapped not really ignored, as it affects another
 190          *  parameter.  This is the actual behavior: lpBytesReturned must be
 191          *  specified, even though lpBytesReturned is documented as:
 192          *
 193          *  "Not used with this operation; set to NULL."
 194          */
 195         if (!DeviceIoControl(h, FSCTL_SET_REPARSE_POINT, rpbuf,
 196                              rpbuflen,
 197                              NULL, 0,
 198                              &bytesReturned /* lpBytesReturned */,
 199                              NULL /* lpOverlapped */))
 200         {
 201                 DWORD err = GetLastError();
 202                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 203                 {
 204                         args->num_soft_links_failed++;
 205                         if (args->num_soft_links_failed <= MAX_CREATE_SOFT_LINK_WARNINGS) {
 206                                 WARNING("Can't set reparse data on \"%ls\": Access denied!\n"
 207                                         "          You may be trying to extract a symbolic "
 208                                         "link without the\n"
 209                                         "          SeCreateSymbolicLink privilege, which by "
 210                                         "default non-Administrator\n"
 211                                         "          accounts do not have.", path);
 212                         }
 213                         if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS) {
 214                                 WARNING("Suppressing further warnings regarding failure to extract\n"
 215                                         "          reparse points due to insufficient privileges...");
 216                         }
 217                 } else {
 218                         ERROR("Failed to set reparse data on \"%ls\"", path);
 219                         win32_error(err);
 220                         if (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
 221                             inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT)
 222                                 return WIMLIB_ERR_LINK;
 223                         else
 224                                 return WIMLIB_ERR_WRITE;
 225                 }
 226         }
 227         return 0;
 228 }
 229
 230 /* Wrapper around the FSCTL_SET_COMPRESSION ioctl to change the
 231  * FILE_ATTRIBUTE_COMPRESSED flag of a file or directory. */
 232 static int
 233 win32_set_compression_state(HANDLE hFile, USHORT format, const wchar_t *path)
 234 {
 235         DWORD bytesReturned;
 236         if (!DeviceIoControl(hFile, FSCTL_SET_COMPRESSION,
 237                              &format, sizeof(USHORT),
 238                              NULL, 0,
 239                              &bytesReturned, NULL))
 240         {
 241                 /* Could be a warning only, but we only call this if the volume
 242                  * supports compression.  So I'm calling this an error. */
 243                 DWORD err = GetLastError();
 244                 ERROR("Failed to set compression flag on \"%ls\"", path);
 245                 win32_error(err);
 246                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 247                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 248                 else
 249                         return WIMLIB_ERR_WRITE;
 250         }
 251         return 0;
 252 }
 253
 254 /* Wrapper around FSCTL_SET_SPARSE ioctl to set a file as sparse. */
 255 static int
 256 win32_set_sparse(HANDLE hFile, const wchar_t *path)
 257 {
 258         DWORD bytesReturned;
 259         if (!DeviceIoControl(hFile, FSCTL_SET_SPARSE,
 260                              NULL, 0,
 261                              NULL, 0,
 262                              &bytesReturned, NULL))
 263         {
 264                 /* Could be a warning only, but we only call this if the volume
 265                  * supports sparse files.  So I'm calling this an error. */
 266                 DWORD err = GetLastError();
 267                 WARNING("Failed to set sparse flag on \"%ls\"", path);
 268                 win32_error(err);
 269                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 270                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 271                 else
 272                         return WIMLIB_ERR_WRITE;
 273         }
 274         return 0;
 275 }
 276
 277 /*
 278  * Sets the security descriptor on an extracted file.
 279  */
 280 static int
 281 win32_set_security_data(const struct wim_inode *inode,
 282                         HANDLE hFile,
 283                         const wchar_t *path,
 284                         struct apply_args *args)
 285 {
 286         PSECURITY_DESCRIPTOR descriptor;
 287         unsigned long n;
 288         DWORD err;
 289         const struct wim_security_data *sd;
 290
 291         SECURITY_INFORMATION securityInformation = 0;
 292
 293         void *owner = NULL;
 294         void *group = NULL;
 295         ACL *dacl = NULL;
 296         ACL *sacl = NULL;
 297
 298         BOOL owner_defaulted;
 299         BOOL group_defaulted;
 300         BOOL dacl_present;
 301         BOOL dacl_defaulted;
 302         BOOL sacl_present;
 303         BOOL sacl_defaulted;
 304
 305         sd = wim_const_security_data(args->w);
 306         descriptor = sd->descriptors[inode->i_security_id];
 307
 308         GetSecurityDescriptorOwner(descriptor, &owner, &owner_defaulted);
 309         if (owner)
 310                 securityInformation |= OWNER_SECURITY_INFORMATION;
 311
 312         GetSecurityDescriptorGroup(descriptor, &group, &group_defaulted);
 313         if (group)
 314                 securityInformation |= GROUP_SECURITY_INFORMATION;
 315
 316         GetSecurityDescriptorDacl(descriptor, &dacl_present,
 317                                   &dacl, &dacl_defaulted);
 318         if (dacl)
 319                 securityInformation |= DACL_SECURITY_INFORMATION;
 320
 321         GetSecurityDescriptorSacl(descriptor, &sacl_present,
 322                                   &sacl, &sacl_defaulted);
 323         if (sacl)
 324                 securityInformation |= SACL_SECURITY_INFORMATION;
 325
 326 again:
 327         if (securityInformation == 0)
 328                 return 0;
 329         if (SetSecurityInfo(hFile, SE_FILE_OBJECT,
 330                             securityInformation, owner, group, dacl, sacl))
 331                 return 0;
 332         err = GetLastError();
 333         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
 334                 goto fail;
 335         switch (err) {
 336         case ERROR_PRIVILEGE_NOT_HELD:
 337                 if (securityInformation & SACL_SECURITY_INFORMATION) {
 338                         n = args->num_set_sacl_priv_notheld++;
 339                         securityInformation &= ~SACL_SECURITY_INFORMATION;
 340                         sacl = NULL;
 341                         if (n < MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
 342                                 WARNING(
 343 "We don't have enough privileges to set the full security\n"
 344 "          descriptor on \"%ls\"!\n", path);
 345                                 if (args->num_set_sd_access_denied +
 346                                     args->num_set_sacl_priv_notheld == 1)
 347                                 {
 348                                         WARNING("%ls", apply_access_denied_msg);
 349                                 }
 350                                 WARNING("Re-trying with SACL omitted.\n", path);
 351                         } else if (n == MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
 352                                 WARNING(
 353 "Suppressing further 'privileges not held' error messages when setting\n"
 354 "          security descriptors.");
 355                         }
 356                         goto again;
 357                 }
 358                 /* Fall through */
 359         case ERROR_INVALID_OWNER:
 360         case ERROR_ACCESS_DENIED:
 361                 n = args->num_set_sd_access_denied++;
 362                 if (n < MAX_SET_SD_ACCESS_DENIED_WARNINGS) {
 363                         WARNING("Failed to set security descriptor on \"%ls\": "
 364                                 "Access denied!\n", path);
 365                         if (args->num_set_sd_access_denied +
 366                             args->num_set_sacl_priv_notheld == 1)
 367                         {
 368                                 WARNING("%ls", apply_access_denied_msg);
 369                         }
 370                 } else if (n == MAX_SET_SD_ACCESS_DENIED_WARNINGS) {
 371                         WARNING(
 372 "Suppressing further access denied error messages when setting\n"
 373 "          security descriptors");
 374                 }
 375                 return 0;
 376         default:
 377 fail:
 378                 ERROR("Failed to set security descriptor on \"%ls\"", path);
 379                 win32_error(err);
 380                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 381                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 382                 else
 383                         return WIMLIB_ERR_WRITE;
 384         }
 385 }
 386
 387
 388 static int
 389 win32_extract_chunk(const void *buf, size_t len, void *arg)
 390 {
 391         HANDLE hStream = arg;
 392
 393         DWORD nbytes_written;
 394         wimlib_assert(len <= 0xffffffff);
 395
 396         if (!WriteFile(hStream, buf, len, &nbytes_written, NULL) ||
 397             nbytes_written != len)
 398         {
 399                 DWORD err = GetLastError();
 400                 ERROR("WriteFile(): write error");
 401                 win32_error(err);
 402                 return WIMLIB_ERR_WRITE;
 403         }
 404         return 0;
 405 }
 406
 407 static int
 408 do_win32_extract_stream(HANDLE hStream, const struct wim_lookup_table_entry *lte)
 409 {
 410         return extract_wim_resource(lte, wim_resource_size(lte),
 411                                     win32_extract_chunk, hStream);
 412 }
 413
 414 struct win32_encrypted_extract_ctx {
 415         const struct wim_lookup_table_entry *lte;
 416         u64 offset;
 417 };
 418
 419 static DWORD WINAPI
 420 win32_encrypted_import_cb(unsigned char *data, void *_ctx,
 421                           unsigned long *len_p)
 422 {
 423         struct win32_encrypted_extract_ctx *ctx = _ctx;
 424         unsigned long len = *len_p;
 425         const struct wim_lookup_table_entry *lte = ctx->lte;
 426
 427         len = min(len, wim_resource_size(lte) - ctx->offset);
 428
 429         if (read_partial_wim_resource_into_buf(lte, len, ctx->offset, data))
 430                 return ERROR_READ_FAULT;
 431
 432         ctx->offset += len;
 433         *len_p = len;
 434         return ERROR_SUCCESS;
 435 }
 436
 437 /* Create an encrypted file and extract the raw encrypted data to it.
 438  *
 439  * @path:  Path to encrypted file to create.
 440  * @lte:   WIM lookup_table entry for the raw encrypted data.
 441  *
 442  * This is separate from do_win32_extract_stream() because the WIM is supposed
 443  * to contain the *raw* encrypted data, which needs to be extracted ("imported")
 444  * using the special APIs OpenEncryptedFileRawW(), WriteEncryptedFileRaw(), and
 445  * CloseEncryptedFileRaw().
 446  *
 447  * Returns 0 on success; nonzero on failure.
 448  */
 449 static int
 450 do_win32_extract_encrypted_stream(const wchar_t *path,
 451                                   const struct wim_lookup_table_entry *lte)
 452 {
 453         void *file_ctx;
 454         int ret;
 455
 456         DEBUG("Opening file \"%ls\" to extract raw encrypted data", path);
 457
 458         ret = OpenEncryptedFileRawW(path, CREATE_FOR_IMPORT, &file_ctx);
 459         if (ret) {
 460                 ERROR("Failed to open \"%ls\" to write raw encrypted data", path);
 461                 win32_error(ret);
 462                 return WIMLIB_ERR_OPEN;
 463         }
 464
 465         if (lte) {
 466                 struct win32_encrypted_extract_ctx ctx;
 467
 468                 ctx.lte = lte;
 469                 ctx.offset = 0;
 470                 ret = WriteEncryptedFileRaw(win32_encrypted_import_cb, &ctx, file_ctx);
 471                 if (ret == ERROR_SUCCESS) {
 472                         ret = 0;
 473                 } else {
 474                         ret = WIMLIB_ERR_WRITE;
 475                         ERROR("Failed to extract encrypted file \"%ls\"", path);
 476                 }
 477         }
 478         CloseEncryptedFileRaw(file_ctx);
 479         return ret;
 480 }
 481
 482 static bool
 483 path_is_root_of_drive(const wchar_t *path)
 484 {
 485         if (*path == L'\0')
 486                 return false;
 487
 488         if (!wcsncmp(path, L"\\\\?\\", 4))
 489                 path += 4;
 490
 491         if (*path != L'/' && *path != L'\\') {
 492                 if (*(path + 1) == L':')
 493                         path += 2;
 494                 else
 495                         return false;
 496         }
 497         while (*path == L'/' || *path == L'\\')
 498                 path++;
 499         return (*path == L'\0');
 500 }
 501
 502 static inline DWORD
 503 win32_mask_attributes(DWORD i_attributes)
 504 {
 505         return i_attributes & ~(FILE_ATTRIBUTE_SPARSE_FILE |
 506                                 FILE_ATTRIBUTE_COMPRESSED |
 507                                 FILE_ATTRIBUTE_REPARSE_POINT |
 508                                 FILE_ATTRIBUTE_DIRECTORY |
 509                                 FILE_ATTRIBUTE_ENCRYPTED |
 510                                 FILE_FLAG_DELETE_ON_CLOSE |
 511                                 FILE_FLAG_NO_BUFFERING |
 512                                 FILE_FLAG_OPEN_NO_RECALL |
 513                                 FILE_FLAG_OVERLAPPED |
 514                                 FILE_FLAG_RANDOM_ACCESS |
 515                                 /*FILE_FLAG_SESSION_AWARE |*/
 516                                 FILE_FLAG_SEQUENTIAL_SCAN |
 517                                 FILE_FLAG_WRITE_THROUGH);
 518 }
 519
 520 static inline DWORD
 521 win32_get_create_flags_and_attributes(DWORD i_attributes)
 522 {
 523         /*
 524          * Some attributes cannot be set by passing them to CreateFile().  In
 525          * particular:
 526          *
 527          * FILE_ATTRIBUTE_DIRECTORY:
 528          *   CreateDirectory() must be called instead of CreateFile().
 529          *
 530          * FILE_ATTRIBUTE_SPARSE_FILE:
 531          *   Needs an ioctl.
 532          *   See: win32_set_sparse().
 533          *
 534          * FILE_ATTRIBUTE_COMPRESSED:
 535          *   Not clear from the documentation, but apparently this needs an
 536          *   ioctl as well.
 537          *   See: win32_set_compressed().
 538          *
 539          * FILE_ATTRIBUTE_REPARSE_POINT:
 540          *   Needs an ioctl, with the reparse data specified.
 541          *   See: win32_set_reparse_data().
 542          *
 543          * In addition, clear any file flags in the attributes that we don't
 544          * want, but also specify FILE_FLAG_OPEN_REPARSE_POINT and
 545          * FILE_FLAG_BACKUP_SEMANTICS as we are a backup application.
 546          */
 547         return win32_mask_attributes(i_attributes) |
 548                 FILE_FLAG_OPEN_REPARSE_POINT |
 549                 FILE_FLAG_BACKUP_SEMANTICS;
 550 }
 551
 552 /* Set compression and/or sparse attributes on a stream, if supported by the
 553  * volume. */
 554 static int
 555 win32_set_special_stream_attributes(HANDLE hFile, const struct wim_inode *inode,
 556                                     struct wim_lookup_table_entry *unnamed_stream_lte,
 557                                     const wchar_t *path, unsigned vol_flags)
 558 {
 559         int ret;
 560
 561         if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
 562                 if (vol_flags & FILE_FILE_COMPRESSION) {
 563                         ret = win32_set_compression_state(hFile,
 564                                                           COMPRESSION_FORMAT_DEFAULT,
 565                                                           path);
 566                         if (ret)
 567                                 return ret;
 568                 } else {
 569                         DEBUG("Cannot set compression attribute on \"%ls\": "
 570                               "volume does not support transparent compression",
 571                               path);
 572                 }
 573         }
 574
 575         if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE) {
 576                 if (vol_flags & FILE_SUPPORTS_SPARSE_FILES) {
 577                         DEBUG("Setting sparse flag on \"%ls\"", path);
 578                         ret = win32_set_sparse(hFile, path);
 579                         if (ret)
 580                                 return ret;
 581                 } else {
 582                         DEBUG("Cannot set sparse attribute on \"%ls\": "
 583                               "volume does not support sparse files",
 584                               path);
 585                 }
 586         }
 587         return 0;
 588 }
 589
 590 /* Pre-create directories; extract encrypted streams */
 591 static int
 592 win32_begin_extract_unnamed_stream(const struct wim_inode *inode,
 593                                    const struct wim_lookup_table_entry *lte,
 594                                    const wchar_t *path,
 595                                    DWORD *creationDisposition_ret,
 596                                    unsigned int vol_flags)
 597 {
 598         DWORD err;
 599         int ret;
 600
 601         /* Directories must be created with CreateDirectoryW().  Then the call
 602          * to CreateFileW() will merely open the directory that was already
 603          * created rather than creating a new file. */
 604         if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY &&
 605             !path_is_root_of_drive(path)) {
 606                 if (!CreateDirectoryW(path, NULL)) {
 607                         err = GetLastError();
 608                         if (err != ERROR_ALREADY_EXISTS) {
 609                                 ERROR("Failed to create directory \"%ls\"",
 610                                       path);
 611                                 win32_error(err);
 612                                 return WIMLIB_ERR_MKDIR;
 613                         }
 614                 }
 615                 DEBUG("Created directory \"%ls\"", path);
 616                 *creationDisposition_ret = OPEN_EXISTING;
 617         }
 618         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED &&
 619             vol_flags & FILE_SUPPORTS_ENCRYPTION)
 620         {
 621                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
 622                         unsigned remaining_sharing_violations = 100;
 623                         while (!EncryptFile(path)) {
 624                                 if (remaining_sharing_violations &&
 625                                     err == ERROR_SHARING_VIOLATION)
 626                                 {
 627                                         WARNING("Couldn't encrypt directory \"%ls\" "
 628                                                 "due to sharing violation; re-trying "
 629                                                 "after 100 ms", path);
 630                                         Sleep(100);
 631                                         remaining_sharing_violations--;
 632                                 } else {
 633                                         err = GetLastError();
 634                                         ERROR("Failed to encrypt directory \"%ls\"",
 635                                               path);
 636                                         win32_error(err);
 637                                         return WIMLIB_ERR_WRITE;
 638                                 }
 639                         }
 640                 } else {
 641                         ret = do_win32_extract_encrypted_stream(path, lte);
 642                         if (ret)
 643                                 return ret;
 644                         DEBUG("Extracted encrypted file \"%ls\"", path);
 645                 }
 646                 *creationDisposition_ret = OPEN_EXISTING;
 647         }
 648
 649         /* Set file attributes if we created the file.  Otherwise, we haven't
 650          * created the file set and we will set the attributes in the call to
 651          * CreateFileW().
 652          *
 653          * The FAT filesystem does not let you change the attributes of the root
 654          * directory, so treat that as a special case and do not set attributes.
 655          * */
 656         if (*creationDisposition_ret == OPEN_EXISTING &&
 657             !path_is_root_of_drive(path))
 658         {
 659                 if (!SetFileAttributesW(path,
 660                                         win32_mask_attributes(inode->i_attributes)))
 661                 {
 662                         err = GetLastError();
 663                         ERROR("Failed to set attributes on \"%ls\"", path);
 664                         win32_error(err);
 665                         return WIMLIB_ERR_WRITE;
 666                 }
 667         }
 668         return 0;
 669 }
 670
 671 /* Set security descriptor and extract stream data or reparse data (skip the
 672  * unnamed data stream of encrypted files, which was already extracted). */
 673 static int
 674 win32_finish_extract_stream(HANDLE h, const struct wim_dentry *dentry,
 675                             const struct wim_lookup_table_entry *lte,
 676                             const wchar_t *stream_path,
 677                             const wchar_t *stream_name_utf16,
 678                             struct apply_args *args)
 679 {
 680         int ret = 0;
 681         const struct wim_inode *inode = dentry->d_inode;
 682         if (stream_name_utf16 == NULL) {
 683                 /* Unnamed stream. */
 684
 685                 /* Set security descriptor, unless the extract_flags indicate
 686                  * not to or the volume does not supported it.  Note that this
 687                  * is only done when the unnamed stream is being extracted, as
 688                  * security descriptors are per-file and not per-stream. */
 689                 if (inode->i_security_id >= 0 &&
 690                     !(args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
 691                     && (args->vol_flags & FILE_PERSISTENT_ACLS))
 692                 {
 693                         ret = win32_set_security_data(inode, h, stream_path, args);
 694                         if (ret)
 695                                 return ret;
 696                 }
 697
 698                 /* Handle reparse points.  The data for them needs to be set
 699                  * using a special ioctl.  Note that the reparse point may have
 700                  * been created using CreateFileW() in the case of
 701                  * non-directories or CreateDirectoryW() in the case of
 702                  * directories; but the ioctl works either way.  Also, it is
 703                  * only this step that actually sets the
 704                  * FILE_ATTRIBUTE_REPARSE_POINT, as it is not valid to set it
 705                  * using SetFileAttributesW() or CreateFileW().
 706                  *
 707                  * If the volume does not support reparse points we simply
 708                  * ignore the reparse data.  (N.B. the code currently doesn't
 709                  * actually reach this case because reparse points are skipped
 710                  * entirely on such volumes.) */
 711                 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 712                         if (args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS) {
 713                                 ret = win32_set_reparse_data(h, inode,
 714                                                              lte, stream_path,
 715                                                              args);
 716                                 if (ret)
 717                                         return ret;
 718                         } else {
 719                                 DEBUG("Cannot set reparse data on \"%ls\": volume "
 720                                       "does not support reparse points", stream_path);
 721                         }
 722                 } else if (lte != NULL &&
 723                            !(args->vol_flags & FILE_SUPPORTS_ENCRYPTION &&
 724                              inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
 725                 {
 726                         /* Extract the data of the unnamed stream, unless the
 727                          * lookup table entry is NULL (indicating an empty
 728                          * stream for which no data needs to be extracted), or
 729                          * the stream is encrypted and therefore was already
 730                          * extracted as a special case. */
 731                         ret = do_win32_extract_stream(h, lte);
 732                         if (ret)
 733                                 return ret;
 734                 }
 735
 736                 if (dentry_has_short_name(dentry))
 737                         SetFileShortNameW(h, dentry->short_name);
 738                 else if (running_on_windows_7_or_later())
 739                         SetFileShortNameW(h, L"");
 740         } else {
 741                 /* Extract the data for a named data stream. */
 742                 if (lte != NULL) {
 743                         DEBUG("Extracting named data stream \"%ls\" (len = %"PRIu64")",
 744                               stream_path, wim_resource_size(lte));
 745                         ret = do_win32_extract_stream(h, lte);
 746                 }
 747         }
 748         return ret;
 749 }
 750
 751 static int
 752 win32_decrypt_file(HANDLE open_handle, const wchar_t *path)
 753 {
 754         DWORD err;
 755         /* We cannot call DecryptFileW() while there is an open handle to the
 756          * file.  So close it first. */
 757         if (!CloseHandle(open_handle)) {
 758                 err = GetLastError();
 759                 ERROR("Failed to close handle for \"%ls\"", path);
 760                 win32_error(err);
 761                 return WIMLIB_ERR_WRITE;
 762         }
 763         if (!DecryptFileW(path, 0 /* reserved parameter; set to 0 */)) {
 764                 err = GetLastError();
 765                 ERROR("Failed to decrypt file \"%ls\"", path);
 766                 win32_error(err);
 767                 return WIMLIB_ERR_WRITE;
 768         }
 769         return 0;
 770 }
 771
 772 /*
 773  * Create and extract a stream to a file, or create a directory, using the
 774  * Windows API.
 775  *
 776  * This handles reparse points, directories, alternate data streams, encrypted
 777  * files, compressed files, etc.
 778  *
 779  * @dentry: WIM dentry for the file or directory being extracted.
 780  *
 781  * @path:  Path to extract the file to.
 782  *
 783  * @stream_name_utf16:
 784  *         Name of the stream, or NULL if the stream is unnamed.  This will
 785  *         be called with a NULL stream_name_utf16 before any non-NULL
 786  *         stream_name_utf16's.
 787  *
 788  * @lte:   WIM lookup table entry for the stream.  May be NULL to indicate
 789  *         a stream of length 0.
 790  *
 791  * @args:  Additional apply context, including flags indicating supported
 792  *         volume features.
 793  *
 794  * Returns 0 on success; nonzero on failure.
 795  */
 796 static int
 797 win32_extract_stream(const struct wim_dentry *dentry,
 798                      const wchar_t *path,
 799                      const wchar_t *stream_name_utf16,
 800                      struct wim_lookup_table_entry *lte,
 801                      struct apply_args *args)
 802 {
 803         wchar_t *stream_path;
 804         HANDLE h;
 805         int ret;
 806         DWORD err;
 807         DWORD creationDisposition = CREATE_ALWAYS;
 808         DWORD requestedAccess;
 809         BY_HANDLE_FILE_INFORMATION file_info;
 810         unsigned remaining_sharing_violations = 1000;
 811         const struct wim_inode *inode = dentry->d_inode;
 812
 813         if (stream_name_utf16) {
 814                 /* Named stream.  Create a buffer that contains the UTF-16LE
 815                  * string [./]path:stream_name_utf16.  This is needed to
 816                  * create and open the stream using CreateFileW().  I'm not
 817                  * aware of any other APIs to do this.  Note: the '$DATA' suffix
 818                  * seems to be unneeded.  Additional note: a "./" prefix needs
 819                  * to be added when the path is not absolute to avoid ambiguity
 820                  * with drive letters. */
 821                 size_t stream_path_nchars;
 822                 size_t path_nchars;
 823                 size_t stream_name_nchars;
 824                 const wchar_t *prefix;
 825
 826                 path_nchars = wcslen(path);
 827                 stream_name_nchars = wcslen(stream_name_utf16);
 828                 stream_path_nchars = path_nchars + 1 + stream_name_nchars;
 829                 if (path[0] != cpu_to_le16(L'\0') &&
 830                     path[0] != cpu_to_le16(L'/') &&
 831                     path[0] != cpu_to_le16(L'\\') &&
 832                     path[1] != cpu_to_le16(L':'))
 833                 {
 834                         prefix = L"./";
 835                         stream_path_nchars += 2;
 836                 } else {
 837                         prefix = L"";
 838                 }
 839                 stream_path = alloca((stream_path_nchars + 1) * sizeof(wchar_t));
 840                 swprintf(stream_path, L"%ls%ls:%ls",
 841                          prefix, path, stream_name_utf16);
 842         } else {
 843                 /* Unnamed stream; its path is just the path to the file itself.
 844                  * */
 845                 stream_path = (wchar_t*)path;
 846
 847                 ret = win32_begin_extract_unnamed_stream(inode, lte, path,
 848                                                          &creationDisposition,
 849                                                          args->vol_flags);
 850                 if (ret)
 851                         goto fail;
 852         }
 853
 854         DEBUG("Opening \"%ls\"", stream_path);
 855         /* DELETE access is needed for SetFileShortNameW(), for some reason. */
 856         requestedAccess = GENERIC_READ | GENERIC_WRITE | DELETE |
 857                           ACCESS_SYSTEM_SECURITY;
 858 try_open_again:
 859         /* Open the stream to be extracted.  Depending on what we have set
 860          * creationDisposition to, we may be creating this for the first time,
 861          * or we may be opening on existing stream we already created using
 862          * CreateDirectoryW() or OpenEncryptedFileRawW(). */
 863         h = CreateFileW(stream_path,
 864                         requestedAccess,
 865                         FILE_SHARE_READ,
 866                         NULL,
 867                         creationDisposition,
 868                         win32_get_create_flags_and_attributes(inode->i_attributes),
 869                         NULL);
 870         if (h == INVALID_HANDLE_VALUE) {
 871                 err = GetLastError();
 872                 if (err == ERROR_ACCESS_DENIED &&
 873                     path_is_root_of_drive(stream_path))
 874                 {
 875                         ret = 0;
 876                         goto out;
 877                 }
 878                 if ((err == ERROR_PRIVILEGE_NOT_HELD ||
 879                      err == ERROR_ACCESS_DENIED) &&
 880                     (requestedAccess & ACCESS_SYSTEM_SECURITY))
 881                 {
 882                         /* Try opening the file again without privilege to
 883                          * modify SACL. */
 884                         requestedAccess &= ~ACCESS_SYSTEM_SECURITY;
 885                         goto try_open_again;
 886                 }
 887                 if (err == ERROR_SHARING_VIOLATION) {
 888                         if (remaining_sharing_violations) {
 889                                 --remaining_sharing_violations;
 890                                 /* This can happen when restoring encrypted directories
 891                                  * for some reason.  Probably a bug in EncryptFile(). */
 892                                 WARNING("Couldn't open \"%ls\" due to sharing violation; "
 893                                         "re-trying after 100ms", stream_path);
 894                                 Sleep(100);
 895                                 goto try_open_again;
 896                         } else {
 897                                 ERROR("Too many sharing violations; giving up...");
 898                         }
 899                 } else {
 900                         if (creationDisposition == OPEN_EXISTING)
 901                                 ERROR("Failed to open \"%ls\"", stream_path);
 902                         else
 903                                 ERROR("Failed to create \"%ls\"", stream_path);
 904                         win32_error(err);
 905                 }
 906                 ret = WIMLIB_ERR_OPEN;
 907                 goto fail;
 908         }
 909
 910         /* Check the attributes of the file we just opened, and remove
 911          * encryption or compression if either was set by default but is not
 912          * supposed to be set based on the WIM inode attributes. */
 913         if (!GetFileInformationByHandle(h, &file_info)) {
 914                 err = GetLastError();
 915                 ERROR("Failed to get attributes of \"%ls\"", stream_path);
 916                 win32_error(err);
 917                 ret = WIMLIB_ERR_STAT;
 918                 goto fail_close_handle;
 919         }
 920
 921         /* Remove encryption? */
 922         if (file_info.dwFileAttributes & FILE_ATTRIBUTE_ENCRYPTED &&
 923             !(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
 924         {
 925                 /* File defaulted to encrypted due to being in an encrypted
 926                  * directory, but is not actually supposed to be encrypted.
 927                  *
 928                  * This is a workaround, because I'm not aware of any way to
 929                  * directly (e.g. with CreateFileW()) create an unencrypted file
 930                  * in a directory with FILE_ATTRIBUTE_ENCRYPTED set. */
 931                 ret = win32_decrypt_file(h, stream_path);
 932                 if (ret)
 933                         goto fail; /* win32_decrypt_file() closed the handle. */
 934                 creationDisposition = OPEN_EXISTING;
 935                 goto try_open_again;
 936         }
 937
 938         /* Remove compression? */
 939         if (file_info.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED &&
 940             !(inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED))
 941         {
 942                 /* Similar to the encrypted case, above, if the file defaulted
 943                  * to compressed due to being in an compressed directory, but is
 944                  * not actually supposed to be compressed, explicitly set the
 945                  * compression format to COMPRESSION_FORMAT_NONE. */
 946                 ret = win32_set_compression_state(h, COMPRESSION_FORMAT_NONE,
 947                                                   stream_path);
 948                 if (ret)
 949                         goto fail_close_handle;
 950         }
 951
 952         /* Set compression and/or sparse attributes if needed */
 953         ret = win32_set_special_stream_attributes(h, inode, lte, path,
 954                                                   args->vol_flags);
 955
 956         if (ret)
 957                 goto fail_close_handle;
 958
 959         /* At this point we have at least created the needed stream with the
 960          * appropriate attributes.  We have yet to set the appropriate security
 961          * descriptor and actually extract the stream data (other than for
 962          * extracted files, which were already extracted).
 963          * win32_finish_extract_stream() handles these additional steps. */
 964         ret = win32_finish_extract_stream(h, dentry, lte, stream_path,
 965                                           stream_name_utf16, args);
 966         if (ret)
 967                 goto fail_close_handle;
 968
 969         /* Done extracting the stream.  Close the handle and return. */
 970         DEBUG("Closing \"%ls\"", stream_path);
 971         if (!CloseHandle(h)) {
 972                 err = GetLastError();
 973                 ERROR("Failed to close \"%ls\"", stream_path);
 974                 win32_error(err);
 975                 ret = WIMLIB_ERR_WRITE;
 976                 goto fail;
 977         }
 978         ret = 0;
 979         goto out;
 980 fail_close_handle:
 981         CloseHandle(h);
 982 fail:
 983         ERROR("Error extracting \"%ls\"", stream_path);
 984 out:
 985         return ret;
 986 }
 987
 988 /*
 989  * Creates a file, directory, or reparse point and extracts all streams to it
 990  * (unnamed data stream and/or reparse point stream, plus any alternate data
 991  * streams).  Handles sparse, compressed, and/or encrypted files.
 992  *
 993  * @dentry:     WIM dentry for this file or directory.
 994  * @path:       UTF-16LE external path to extract the inode to.
 995  * @args:       Additional extraction context.
 996  *
 997  * Returns 0 on success; nonzero on failure.
 998  */
 999 static int
1000 win32_extract_streams(const struct wim_dentry *dentry,
1001                       const wchar_t *path, struct apply_args *args)
1002 {
1003         struct wim_lookup_table_entry *unnamed_lte;
1004         int ret;
1005         const struct wim_inode *inode = dentry->d_inode;
1006
1007         /* First extract the unnamed stream. */
1008
1009         unnamed_lte = inode_unnamed_lte_resolved(inode);
1010         ret = win32_extract_stream(dentry, path, NULL, unnamed_lte, args);
1011         if (ret)
1012                 goto out;
1013
1014         /* Extract any named streams, if supported by the volume. */
1015
1016         if (!(args->vol_flags & FILE_NAMED_STREAMS))
1017                 goto out;
1018         for (u16 i = 0; i < inode->i_num_ads; i++) {
1019                 const struct wim_ads_entry *ads_entry = &inode->i_ads_entries[i];
1020
1021                 /* Skip the unnamed stream if it's in the ADS entries (we
1022                  * already extracted it...) */
1023                 if (ads_entry->stream_name_nbytes == 0)
1024                         continue;
1025
1026                 /* Skip special UNIX data entries (see documentation for
1027                  * WIMLIB_ADD_FLAG_UNIX_DATA) */
1028                 if (ads_entry->stream_name_nbytes == WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES
1029                     && !memcmp(ads_entry->stream_name,
1030                                WIMLIB_UNIX_DATA_TAG_UTF16LE,
1031                                WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES))
1032                         continue;
1033
1034                 /* Extract the named stream */
1035                 ret = win32_extract_stream(dentry,
1036                                            path,
1037                                            ads_entry->stream_name,
1038                                            ads_entry->lte,
1039                                            args);
1040                 if (ret)
1041                         break;
1042         }
1043 out:
1044         return ret;
1045 }
1046
1047 static int
1048 dentry_clear_inode_visited(struct wim_dentry *dentry, void *_ignore)
1049 {
1050         dentry->d_inode->i_visited = 0;
1051         return 0;
1052 }
1053
1054 static int
1055 dentry_get_features(struct wim_dentry *dentry, void *_features_p)
1056 {
1057         DWORD features = 0;
1058         DWORD *features_p = _features_p;
1059         struct wim_inode *inode = dentry->d_inode;
1060
1061         if (inode->i_visited) {
1062                 features |= FILE_SUPPORTS_HARD_LINKS;
1063         } else {
1064                 inode->i_visited = 1;
1065                 if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE)
1066                         features |= FILE_SUPPORTS_SPARSE_FILES;
1067                 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)
1068                         features |= FILE_SUPPORTS_REPARSE_POINTS;
1069                 for (unsigned i = 0; i < inode->i_num_ads; i++)
1070                         if (inode->i_ads_entries[i].stream_name_nbytes)
1071                                 features |= FILE_NAMED_STREAMS;
1072                 if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED)
1073                         features |= FILE_SUPPORTS_ENCRYPTION;
1074                 if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED)
1075                         features |= FILE_FILE_COMPRESSION;
1076                 if (inode->i_security_id != -1)
1077                         features |= FILE_PERSISTENT_ACLS;
1078         }
1079         *features_p |= features;
1080         return 0;
1081 }
1082
1083 /* If not done already, load the supported feature flags for the volume onto
1084  * which the image is being extracted, and warn the user about any missing
1085  * features that could be important. */
1086 static int
1087 win32_check_vol_flags(const wchar_t *output_path,
1088                       struct wim_dentry *root, struct apply_args *args)
1089 {
1090         DWORD dentry_features = 0;
1091         DWORD missing_features;
1092
1093         if (args->have_vol_flags)
1094                 return 0;
1095
1096         for_dentry_in_tree(root, dentry_clear_inode_visited, NULL);
1097         for_dentry_in_tree(root, dentry_get_features, &dentry_features);
1098
1099         win32_get_vol_flags(output_path, &args->vol_flags);
1100         args->have_vol_flags = true;
1101
1102         missing_features = dentry_features & ~args->vol_flags;
1103
1104         /* Warn the user about data that may not be extracted. */
1105         if (missing_features & FILE_SUPPORTS_SPARSE_FILES)
1106                 WARNING("Volume does not support sparse files!\n"
1107                         "          Sparse files will be extracted as non-sparse.");
1108         if (missing_features & FILE_SUPPORTS_REPARSE_POINTS)
1109                 WARNING("Volume does not support reparse points!\n"
1110                         "          Reparse point data will not be extracted.");
1111         if (missing_features & FILE_NAMED_STREAMS) {
1112                 WARNING("Volume does not support named data streams!\n"
1113                         "          Named data streams will not be extracted.");
1114         }
1115         if (missing_features & FILE_SUPPORTS_ENCRYPTION) {
1116                 WARNING("Volume does not support encryption!\n"
1117                         "          Encrypted files will be extracted as raw data.");
1118         }
1119         if (missing_features & FILE_FILE_COMPRESSION) {
1120                 WARNING("Volume does not support transparent compression!\n"
1121                         "          Compressed files will be extracted as non-compressed.");
1122         }
1123         if (missing_features & FILE_PERSISTENT_ACLS) {
1124                 if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
1125                         ERROR("Strict ACLs requested, but the volume does not "
1126                               "support ACLs!");
1127                         return WIMLIB_ERR_VOLUME_LACKS_FEATURES;
1128                 } else {
1129                         WARNING("Volume does not support persistent ACLS!\n"
1130                                 "          File permissions will not be extracted.");
1131                 }
1132         }
1133         if (running_on_windows_7_or_later() &&
1134             (missing_features & FILE_SUPPORTS_HARD_LINKS))
1135         {
1136                 WARNING("Volume does not support hard links!\n"
1137                         "          Hard links will be extracted as duplicate files.");
1138         }
1139         return 0;
1140 }
1141
1142 /*
1143  * Try extracting a hard link.
1144  *
1145  * @output_path:  Path to link to be extracted.
1146  *
1147  * @inode:        WIM inode that the link is to; inode->i_extracted_file
1148  *                the path to a name of the file that has already been
1149  *                extracted (we use this to create the hard link).
1150  *
1151  * @args:         Additional apply context, used here to keep track of
1152  *                the number of times creating a hard link failed due to
1153  *                ERROR_INVALID_FUNCTION.  This error should indicate that hard
1154  *                links are not supported by the volume, and we would like to
1155  *                warn the user a few times, but not too many times.
1156  *
1157  * Returns 0 if the hard link was successfully extracted.  Returns
1158  * WIMLIB_ERR_LINK (> 0) if an error occurred, other than hard links possibly
1159  * being unsupported by the volume.  Returns a negative value if creating the
1160  * hard link failed due to ERROR_INVALID_FUNCTION.
1161  */
1162 static int
1163 win32_try_hard_link(const wchar_t *output_path, const struct wim_inode *inode,
1164                     struct apply_args *args)
1165 {
1166         DWORD err;
1167
1168         /* There is a volume flag for this (FILE_SUPPORTS_HARD_LINKS),
1169          * but it's only available on Windows 7 and later.
1170          *
1171          * Otherwise, CreateHardLinkW() will apparently return
1172          * ERROR_INVALID_FUNCTION if the volume does not support hard links. */
1173
1174         DEBUG("Creating hard link \"%ls => %ls\"",
1175               output_path, inode->i_extracted_file);
1176
1177         if (running_on_windows_7_or_later() &&
1178             !(args->vol_flags & FILE_SUPPORTS_HARD_LINKS))
1179                 goto hard_links_unsupported;
1180
1181         if (CreateHardLinkW(output_path, inode->i_extracted_file, NULL))
1182                 return 0;
1183
1184         err = GetLastError();
1185         if (err != ERROR_INVALID_FUNCTION) {
1186                 ERROR("Can't create hard link \"%ls => %ls\"",
1187                       output_path, inode->i_extracted_file);
1188                 win32_error(err);
1189                 return WIMLIB_ERR_LINK;
1190         }
1191 hard_links_unsupported:
1192         args->num_hard_links_failed++;
1193         if (args->num_hard_links_failed <= MAX_CREATE_HARD_LINK_WARNINGS) {
1194                 if (running_on_windows_7_or_later())
1195                 {
1196                         WARNING("Extracting duplicate copy of \"%ls\" "
1197                                 "rather than hard link", output_path);
1198                 } else {
1199                         WARNING("Can't create hard link \"%ls\" => \"%ls\":\n"
1200                                 "          Volume does not support hard links!\n"
1201                                 "          Falling back to extracting a copy of the file.",
1202                                 output_path, inode->i_extracted_file);
1203                 }
1204         }
1205         if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS)
1206                 WARNING("Suppressing further hard linking warnings...");
1207         return -1;
1208 }
1209
1210 /* Extract a file, directory, reparse point, or hard link to an
1211  * already-extracted file using the Win32 API */
1212 int
1213 win32_do_apply_dentry(const wchar_t *output_path,
1214                       size_t output_path_num_chars,
1215                       struct wim_dentry *dentry,
1216                       struct apply_args *args)
1217 {
1218         int ret;
1219         struct wim_inode *inode = dentry->d_inode;
1220
1221         ret = win32_check_vol_flags(output_path, dentry, args);
1222         if (ret)
1223                 return ret;
1224         if (inode->i_nlink > 1 && inode->i_extracted_file != NULL) {
1225                 /* Linked file, with another name already extracted.  Create a
1226                  * hard link. */
1227                 ret = win32_try_hard_link(output_path, inode, args);
1228                 if (ret >= 0)
1229                         return ret;
1230                 /* Negative return value from win32_try_hard_link() indicates
1231                  * that hard links are probably not supported by the volume.
1232                  * Fall back to extracting a copy of the file. */
1233         }
1234
1235         /* If this is a reparse point and the volume does not support reparse
1236          * points, just skip it completely. */
1237         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
1238             !(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
1239         {
1240                 WARNING("Not extracting reparse point \"%ls\"", output_path);
1241                 dentry->not_extracted = 1;
1242         } else {
1243                 /* Create the file, directory, or reparse point, and extract the
1244                  * data streams. */
1245                 ret = win32_extract_streams(dentry, output_path, args);
1246                 if (ret)
1247                         return ret;
1248         }
1249         if (inode->i_extracted_file == NULL) {
1250                 const struct wim_lookup_table_entry *lte;
1251
1252                 /* Tally bytes extracted, including all alternate data streams,
1253                  * unless we extracted a hard link (or, at least extracted a
1254                  * name that was supposed to be a hard link) */
1255                 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1256                         lte = inode_stream_lte_resolved(inode, i);
1257                         if (lte)
1258                                 args->progress.extract.completed_bytes +=
1259                                                         wim_resource_size(lte);
1260                 }
1261                 if (inode->i_nlink > 1) {
1262                         /* Save extracted path for a later call to
1263                          * CreateHardLinkW() if this inode has multiple links.
1264                          * */
1265                         inode->i_extracted_file = WCSDUP(output_path);
1266                         if (!inode->i_extracted_file)
1267                                 return WIMLIB_ERR_NOMEM;
1268                 }
1269         }
1270         return 0;
1271 }
1272
1273 /* Set timestamps on an extracted file using the Win32 API */
1274 int
1275 win32_do_apply_dentry_timestamps(const wchar_t *path,
1276                                  size_t path_num_chars,
1277                                  struct wim_dentry *dentry,
1278                                  struct apply_args *args)
1279 {
1280         DWORD err;
1281         HANDLE h;
1282         const struct wim_inode *inode = dentry->d_inode;
1283
1284         /* Windows doesn't let you change the timestamps of the root directory
1285          * (at least on FAT, which is dumb but expected since FAT doesn't store
1286          * any metadata about the root directory...) */
1287         if (path_is_root_of_drive(path))
1288                 return 0;
1289
1290         DEBUG("Opening \"%ls\" to set timestamps", path);
1291         h = win32_open_existing_file(path, FILE_WRITE_ATTRIBUTES);
1292         if (h == INVALID_HANDLE_VALUE) {
1293                 err = GetLastError();
1294                 goto fail;
1295         }
1296
1297         FILETIME creationTime = {.dwLowDateTime = inode->i_creation_time & 0xffffffff,
1298                                  .dwHighDateTime = inode->i_creation_time >> 32};
1299         FILETIME lastAccessTime = {.dwLowDateTime = inode->i_last_access_time & 0xffffffff,
1300                                   .dwHighDateTime = inode->i_last_access_time >> 32};
1301         FILETIME lastWriteTime = {.dwLowDateTime = inode->i_last_write_time & 0xffffffff,
1302                                   .dwHighDateTime = inode->i_last_write_time >> 32};
1303
1304         DEBUG("Calling SetFileTime() on \"%ls\"", path);
1305         if (!SetFileTime(h, &creationTime, &lastAccessTime, &lastWriteTime)) {
1306                 err = GetLastError();
1307                 CloseHandle(h);
1308                 goto fail;
1309         }
1310         DEBUG("Closing \"%ls\"", path);
1311         if (!CloseHandle(h)) {
1312                 err = GetLastError();
1313                 goto fail;
1314         }
1315         goto out;
1316 fail:
1317         /* Only warn if setting timestamps failed; still return 0. */
1318         WARNING("Can't set timestamps on \"%ls\"", path);
1319         win32_error(err);
1320 out:
1321         return 0;
1322 }
1323
1324 #endif /* __WIN32__ */