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                         const wchar_t *extract_root_realpath,
  61                         unsigned extract_root_realpath_nchars)
  62 {
  63         struct reparse_data rpdata;
  64         wchar_t *target;
  65         size_t target_nchars;
  66         size_t stripped_nchars;
  67         wchar_t *stripped_target;
  68         wchar_t stripped_target_nchars;
  69         int ret;
  70
  71         utf16lechar *new_target;
  72         utf16lechar *new_print_name;
  73         size_t new_target_nchars;
  74         size_t new_print_name_nchars;
  75         utf16lechar *p;
  76
  77         ret = parse_reparse_data(rpbuf, 8 + le16_to_cpu(*(u16*)(rpbuf + 4)),
  78                                  &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 + 6;
 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                 wmemcpy(p, L"\\??\\", 4);
 110                 p += 4;
 111         }
 112
 113         /* Print name excludes the \??\ if present. */
 114         new_print_name = p;
 115         if (stripped_nchars != 0) {
 116                 /* Get drive letter from real path to extract root, if a drive
 117                  * letter was present before. */
 118                 *p++ = extract_root_realpath[0];
 119                 *p++ = extract_root_realpath[1];
 120         }
 121         /* Copy the rest of the extract root */
 122         wmemcpy(p, extract_root_realpath + 2, extract_root_realpath_nchars - 2);
 123         p += extract_root_realpath_nchars - 2;
 124
 125         /* Append the stripped target */
 126         wmemcpy(p, stripped_target, stripped_target_nchars);
 127         p += stripped_target_nchars;
 128         new_target_nchars = p - new_target;
 129         new_print_name_nchars = p - new_print_name;
 130
 131         if (new_target_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE ||
 132             new_print_name_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE)
 133         {
 134                 ERROR("Path names too long to do reparse point fixup!");
 135                 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
 136         }
 137         rpdata.substitute_name = new_target;
 138         rpdata.substitute_name_nbytes = new_target_nchars * sizeof(utf16lechar);
 139         rpdata.print_name = new_print_name;
 140         rpdata.print_name_nbytes = new_print_name_nchars * sizeof(utf16lechar);
 141         return make_reparse_buffer(&rpdata, rpbuf);
 142 }
 143
 144 /* Wrapper around the FSCTL_SET_REPARSE_POINT ioctl to set the reparse data on
 145  * an extracted reparse point. */
 146 static int
 147 win32_set_reparse_data(HANDLE h,
 148                        const struct wim_inode *inode,
 149                        const struct wim_lookup_table_entry *lte,
 150                        const wchar_t *path,
 151                        struct apply_args *args)
 152 {
 153         int ret;
 154         u8 rpbuf[REPARSE_POINT_MAX_SIZE];
 155         DWORD bytesReturned;
 156         u16 rpbuflen;
 157
 158         DEBUG("Setting reparse data on \"%ls\"", path);
 159
 160         ret = wim_inode_get_reparse_data(inode, rpbuf, &rpbuflen);
 161         if (ret)
 162                 return ret;
 163
 164         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX &&
 165             (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
 166              inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT) &&
 167             !inode->i_not_rpfixed)
 168         {
 169                 ret = win32_extract_try_rpfix(rpbuf,
 170                                               args->target_realpath,
 171                                               args->target_realpath_len);
 172                 if (ret)
 173                         return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
 174         }
 175
 176         /* Set the reparse data on the open file using the
 177          * FSCTL_SET_REPARSE_POINT ioctl.
 178          *
 179          * There are contradictions in Microsoft's documentation for this:
 180          *
 181          * "If hDevice was opened without specifying FILE_FLAG_OVERLAPPED,
 182          * lpOverlapped is ignored."
 183          *
 184          * --- So setting lpOverlapped to NULL is okay since it's ignored.
 185          *
 186          * "If lpOverlapped is NULL, lpBytesReturned cannot be NULL. Even when an
 187          * operation returns no output data and lpOutBuffer is NULL,
 188          * DeviceIoControl makes use of lpBytesReturned. After such an
 189          * operation, the value of lpBytesReturned is meaningless."
 190          *
 191          * --- So lpOverlapped not really ignored, as it affects another
 192          *  parameter.  This is the actual behavior: lpBytesReturned must be
 193          *  specified, even though lpBytesReturned is documented as:
 194          *
 195          *  "Not used with this operation; set to NULL."
 196          */
 197         if (!DeviceIoControl(h, FSCTL_SET_REPARSE_POINT, rpbuf,
 198                              rpbuflen,
 199                              NULL, 0,
 200                              &bytesReturned /* lpBytesReturned */,
 201                              NULL /* lpOverlapped */))
 202         {
 203                 DWORD err = GetLastError();
 204                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 205                 {
 206                         args->num_soft_links_failed++;
 207                         if (args->num_soft_links_failed <= MAX_CREATE_SOFT_LINK_WARNINGS) {
 208                                 WARNING("Can't set reparse data on \"%ls\": Access denied!\n"
 209                                         "          You may be trying to extract a symbolic "
 210                                         "link without the\n"
 211                                         "          SeCreateSymbolicLink privilege, which by "
 212                                         "default non-Administrator\n"
 213                                         "          accounts do not have.", path);
 214                         }
 215                         if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS) {
 216                                 WARNING("Suppressing further warnings regarding failure to extract\n"
 217                                         "          reparse points due to insufficient privileges...");
 218                         }
 219                 } else {
 220                         ERROR("Failed to set reparse data on \"%ls\"", path);
 221                         win32_error(err);
 222                         if (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
 223                             inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT)
 224                                 return WIMLIB_ERR_LINK;
 225                         else
 226                                 return WIMLIB_ERR_WRITE;
 227                 }
 228         }
 229         return 0;
 230 }
 231
 232 /* Wrapper around the FSCTL_SET_COMPRESSION ioctl to change the
 233  * FILE_ATTRIBUTE_COMPRESSED flag of a file or directory. */
 234 static int
 235 win32_set_compression_state(HANDLE hFile, USHORT format, const wchar_t *path)
 236 {
 237         DWORD bytesReturned;
 238         if (!DeviceIoControl(hFile, FSCTL_SET_COMPRESSION,
 239                              &format, sizeof(USHORT),
 240                              NULL, 0,
 241                              &bytesReturned, NULL))
 242         {
 243                 /* Could be a warning only, but we only call this if the volume
 244                  * supports compression.  So I'm calling this an error. */
 245                 DWORD err = GetLastError();
 246                 ERROR("Failed to set compression flag on \"%ls\"", path);
 247                 win32_error(err);
 248                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 249                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 250                 else
 251                         return WIMLIB_ERR_WRITE;
 252         }
 253         return 0;
 254 }
 255
 256 /* Wrapper around FSCTL_SET_SPARSE ioctl to set a file as sparse. */
 257 static int
 258 win32_set_sparse(HANDLE hFile, const wchar_t *path)
 259 {
 260         DWORD bytesReturned;
 261         if (!DeviceIoControl(hFile, FSCTL_SET_SPARSE,
 262                              NULL, 0,
 263                              NULL, 0,
 264                              &bytesReturned, NULL))
 265         {
 266                 /* Could be a warning only, but we only call this if the volume
 267                  * supports sparse files.  So I'm calling this an error. */
 268                 DWORD err = GetLastError();
 269                 WARNING("Failed to set sparse flag on \"%ls\"", path);
 270                 win32_error(err);
 271                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 272                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 273                 else
 274                         return WIMLIB_ERR_WRITE;
 275         }
 276         return 0;
 277 }
 278
 279 /*
 280  * Sets the security descriptor on an extracted file.
 281  */
 282 static int
 283 win32_set_security_data(const struct wim_inode *inode,
 284                         HANDLE hFile,
 285                         const wchar_t *path,
 286                         struct apply_args *args)
 287 {
 288         PSECURITY_DESCRIPTOR descriptor;
 289         unsigned long n;
 290         DWORD err;
 291         const struct wim_security_data *sd;
 292
 293         SECURITY_INFORMATION securityInformation = 0;
 294
 295         void *owner = NULL;
 296         void *group = NULL;
 297         ACL *dacl = NULL;
 298         ACL *sacl = NULL;
 299
 300         BOOL owner_defaulted;
 301         BOOL group_defaulted;
 302         BOOL dacl_present;
 303         BOOL dacl_defaulted;
 304         BOOL sacl_present;
 305         BOOL sacl_defaulted;
 306
 307         sd = wim_const_security_data(args->w);
 308         descriptor = sd->descriptors[inode->i_security_id];
 309
 310         GetSecurityDescriptorOwner(descriptor, &owner, &owner_defaulted);
 311         if (owner)
 312                 securityInformation |= OWNER_SECURITY_INFORMATION;
 313
 314         GetSecurityDescriptorGroup(descriptor, &group, &group_defaulted);
 315         if (group)
 316                 securityInformation |= GROUP_SECURITY_INFORMATION;
 317
 318         GetSecurityDescriptorDacl(descriptor, &dacl_present,
 319                                   &dacl, &dacl_defaulted);
 320         if (dacl)
 321                 securityInformation |= DACL_SECURITY_INFORMATION;
 322
 323         GetSecurityDescriptorSacl(descriptor, &sacl_present,
 324                                   &sacl, &sacl_defaulted);
 325         if (sacl)
 326                 securityInformation |= SACL_SECURITY_INFORMATION;
 327
 328 again:
 329         if (securityInformation == 0)
 330                 return 0;
 331         if (SetSecurityInfo(hFile, SE_FILE_OBJECT,
 332                             securityInformation, owner, group, dacl, sacl))
 333                 return 0;
 334         err = GetLastError();
 335         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
 336                 goto fail;
 337         switch (err) {
 338         case ERROR_PRIVILEGE_NOT_HELD:
 339                 if (securityInformation & SACL_SECURITY_INFORMATION) {
 340                         n = args->num_set_sacl_priv_notheld++;
 341                         securityInformation &= ~SACL_SECURITY_INFORMATION;
 342                         sacl = NULL;
 343                         if (n < MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
 344                                 WARNING(
 345 "We don't have enough privileges to set the full security\n"
 346 "          descriptor on \"%ls\"!\n", path);
 347                                 if (args->num_set_sd_access_denied +
 348                                     args->num_set_sacl_priv_notheld == 1)
 349                                 {
 350                                         WARNING("%ls", apply_access_denied_msg);
 351                                 }
 352                                 WARNING("Re-trying with SACL omitted.\n", path);
 353                         } else if (n == MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
 354                                 WARNING(
 355 "Suppressing further 'privileges not held' error messages when setting\n"
 356 "          security descriptors.");
 357                         }
 358                         goto again;
 359                 }
 360                 /* Fall through */
 361         case ERROR_INVALID_OWNER:
 362         case ERROR_ACCESS_DENIED:
 363                 n = args->num_set_sd_access_denied++;
 364                 if (n < MAX_SET_SD_ACCESS_DENIED_WARNINGS) {
 365                         WARNING("Failed to set security descriptor on \"%ls\": "
 366                                 "Access denied!\n", path);
 367                         if (args->num_set_sd_access_denied +
 368                             args->num_set_sacl_priv_notheld == 1)
 369                         {
 370                                 WARNING("%ls", apply_access_denied_msg);
 371                         }
 372                 } else if (n == MAX_SET_SD_ACCESS_DENIED_WARNINGS) {
 373                         WARNING(
 374 "Suppressing further access denied error messages when setting\n"
 375 "          security descriptors");
 376                 }
 377                 return 0;
 378         default:
 379 fail:
 380                 ERROR("Failed to set security descriptor on \"%ls\"", path);
 381                 win32_error(err);
 382                 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
 383                         return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
 384                 else
 385                         return WIMLIB_ERR_WRITE;
 386         }
 387 }
 388
 389
 390 static int
 391 win32_extract_chunk(const void *buf, size_t len, void *arg)
 392 {
 393         HANDLE hStream = arg;
 394
 395         DWORD nbytes_written;
 396         wimlib_assert(len <= 0xffffffff);
 397
 398         if (!WriteFile(hStream, buf, len, &nbytes_written, NULL) ||
 399             nbytes_written != len)
 400         {
 401                 DWORD err = GetLastError();
 402                 ERROR("WriteFile(): write error");
 403                 win32_error(err);
 404                 return WIMLIB_ERR_WRITE;
 405         }
 406         return 0;
 407 }
 408
 409 static int
 410 do_win32_extract_stream(HANDLE hStream, const struct wim_lookup_table_entry *lte)
 411 {
 412         return extract_wim_resource(lte, wim_resource_size(lte),
 413                                     win32_extract_chunk, hStream);
 414 }
 415
 416 struct win32_encrypted_extract_ctx {
 417         const struct wim_lookup_table_entry *lte;
 418         u64 offset;
 419 };
 420
 421 static DWORD WINAPI
 422 win32_encrypted_import_cb(unsigned char *data, void *_ctx,
 423                           unsigned long *len_p)
 424 {
 425         struct win32_encrypted_extract_ctx *ctx = _ctx;
 426         unsigned long len = *len_p;
 427         const struct wim_lookup_table_entry *lte = ctx->lte;
 428
 429         len = min(len, wim_resource_size(lte) - ctx->offset);
 430
 431         if (read_partial_wim_resource_into_buf(lte, len, ctx->offset, data))
 432                 return ERROR_READ_FAULT;
 433
 434         ctx->offset += len;
 435         *len_p = len;
 436         return ERROR_SUCCESS;
 437 }
 438
 439 /* Create an encrypted file and extract the raw encrypted data to it.
 440  *
 441  * @path:  Path to encrypted file to create.
 442  * @lte:   WIM lookup_table entry for the raw encrypted data.
 443  *
 444  * This is separate from do_win32_extract_stream() because the WIM is supposed
 445  * to contain the *raw* encrypted data, which needs to be extracted ("imported")
 446  * using the special APIs OpenEncryptedFileRawW(), WriteEncryptedFileRaw(), and
 447  * CloseEncryptedFileRaw().
 448  *
 449  * Returns 0 on success; nonzero on failure.
 450  */
 451 static int
 452 do_win32_extract_encrypted_stream(const wchar_t *path,
 453                                   const struct wim_lookup_table_entry *lte)
 454 {
 455         void *file_ctx;
 456         int ret;
 457
 458         DEBUG("Opening file \"%ls\" to extract raw encrypted data", path);
 459
 460         ret = OpenEncryptedFileRawW(path, CREATE_FOR_IMPORT, &file_ctx);
 461         if (ret) {
 462                 ERROR("Failed to open \"%ls\" to write raw encrypted data", path);
 463                 win32_error(ret);
 464                 return WIMLIB_ERR_OPEN;
 465         }
 466
 467         if (lte) {
 468                 struct win32_encrypted_extract_ctx ctx;
 469
 470                 ctx.lte = lte;
 471                 ctx.offset = 0;
 472                 ret = WriteEncryptedFileRaw(win32_encrypted_import_cb, &ctx, file_ctx);
 473                 if (ret == ERROR_SUCCESS) {
 474                         ret = 0;
 475                 } else {
 476                         ret = WIMLIB_ERR_WRITE;
 477                         ERROR("Failed to extract encrypted file \"%ls\"", path);
 478                 }
 479         }
 480         CloseEncryptedFileRaw(file_ctx);
 481         return ret;
 482 }
 483
 484 static bool
 485 path_is_root_of_drive(const wchar_t *path)
 486 {
 487         if (!*path)
 488                 return false;
 489
 490         if (*path != L'/' && *path != L'\\') {
 491                 if (*(path + 1) == L':')
 492                         path += 2;
 493                 else
 494                         return false;
 495         }
 496         while (*path == L'/' || *path == L'\\')
 497                 path++;
 498         return (*path == L'\0');
 499 }
 500
 501 static inline DWORD
 502 win32_mask_attributes(DWORD i_attributes)
 503 {
 504         return i_attributes & ~(FILE_ATTRIBUTE_SPARSE_FILE |
 505                                 FILE_ATTRIBUTE_COMPRESSED |
 506                                 FILE_ATTRIBUTE_REPARSE_POINT |
 507                                 FILE_ATTRIBUTE_DIRECTORY |
 508                                 FILE_ATTRIBUTE_ENCRYPTED |
 509                                 FILE_FLAG_DELETE_ON_CLOSE |
 510                                 FILE_FLAG_NO_BUFFERING |
 511                                 FILE_FLAG_OPEN_NO_RECALL |
 512                                 FILE_FLAG_OVERLAPPED |
 513                                 FILE_FLAG_RANDOM_ACCESS |
 514                                 /*FILE_FLAG_SESSION_AWARE |*/
 515                                 FILE_FLAG_SEQUENTIAL_SCAN |
 516                                 FILE_FLAG_WRITE_THROUGH);
 517 }
 518
 519 static inline DWORD
 520 win32_get_create_flags_and_attributes(DWORD i_attributes)
 521 {
 522         /*
 523          * Some attributes cannot be set by passing them to CreateFile().  In
 524          * particular:
 525          *
 526          * FILE_ATTRIBUTE_DIRECTORY:
 527          *   CreateDirectory() must be called instead of CreateFile().
 528          *
 529          * FILE_ATTRIBUTE_SPARSE_FILE:
 530          *   Needs an ioctl.
 531          *   See: win32_set_sparse().
 532          *
 533          * FILE_ATTRIBUTE_COMPRESSED:
 534          *   Not clear from the documentation, but apparently this needs an
 535          *   ioctl as well.
 536          *   See: win32_set_compressed().
 537          *
 538          * FILE_ATTRIBUTE_REPARSE_POINT:
 539          *   Needs an ioctl, with the reparse data specified.
 540          *   See: win32_set_reparse_data().
 541          *
 542          * In addition, clear any file flags in the attributes that we don't
 543          * want, but also specify FILE_FLAG_OPEN_REPARSE_POINT and
 544          * FILE_FLAG_BACKUP_SEMANTICS as we are a backup application.
 545          */
 546         return win32_mask_attributes(i_attributes) |
 547                 FILE_FLAG_OPEN_REPARSE_POINT |
 548                 FILE_FLAG_BACKUP_SEMANTICS;
 549 }
 550
 551 /* Set compression and/or sparse attributes on a stream, if supported by the
 552  * volume. */
 553 static int
 554 win32_set_special_stream_attributes(HANDLE hFile, const struct wim_inode *inode,
 555                                     struct wim_lookup_table_entry *unnamed_stream_lte,
 556                                     const wchar_t *path, unsigned vol_flags)
 557 {
 558         int ret;
 559
 560         if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
 561                 if (vol_flags & FILE_FILE_COMPRESSION) {
 562                         ret = win32_set_compression_state(hFile,
 563                                                           COMPRESSION_FORMAT_DEFAULT,
 564                                                           path);
 565                         if (ret)
 566                                 return ret;
 567                 } else {
 568                         DEBUG("Cannot set compression attribute on \"%ls\": "
 569                               "volume does not support transparent compression",
 570                               path);
 571                 }
 572         }
 573
 574         if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE) {
 575                 if (vol_flags & FILE_SUPPORTS_SPARSE_FILES) {
 576                         DEBUG("Setting sparse flag on \"%ls\"", path);
 577                         ret = win32_set_sparse(hFile, path);
 578                         if (ret)
 579                                 return ret;
 580                 } else {
 581                         DEBUG("Cannot set sparse attribute on \"%ls\": "
 582                               "volume does not support sparse files",
 583                               path);
 584                 }
 585         }
 586         return 0;
 587 }
 588
 589 /* Pre-create directories; extract encrypted streams */
 590 static int
 591 win32_begin_extract_unnamed_stream(const struct wim_inode *inode,
 592                                    const struct wim_lookup_table_entry *lte,
 593                                    const wchar_t *path,
 594                                    DWORD *creationDisposition_ret,
 595                                    unsigned int vol_flags)
 596 {
 597         DWORD err;
 598         int ret;
 599
 600         /* Directories must be created with CreateDirectoryW().  Then the call
 601          * to CreateFileW() will merely open the directory that was already
 602          * created rather than creating a new file. */
 603         if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY &&
 604             !path_is_root_of_drive(path)) {
 605                 if (!CreateDirectoryW(path, NULL)) {
 606                         err = GetLastError();
 607                         if (err != ERROR_ALREADY_EXISTS) {
 608                                 ERROR("Failed to create directory \"%ls\"",
 609                                       path);
 610                                 win32_error(err);
 611                                 return WIMLIB_ERR_MKDIR;
 612                         }
 613                 }
 614                 DEBUG("Created directory \"%ls\"", path);
 615                 *creationDisposition_ret = OPEN_EXISTING;
 616         }
 617         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED &&
 618             vol_flags & FILE_SUPPORTS_ENCRYPTION)
 619         {
 620                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
 621                         unsigned remaining_sharing_violations = 100;
 622                         while (!EncryptFile(path)) {
 623                                 if (remaining_sharing_violations &&
 624                                     err == ERROR_SHARING_VIOLATION)
 625                                 {
 626                                         WARNING("Couldn't encrypt directory \"%ls\" "
 627                                                 "due to sharing violation; re-trying "
 628                                                 "after 100 ms", path);
 629                                         Sleep(100);
 630                                         remaining_sharing_violations--;
 631                                 } else {
 632                                         err = GetLastError();
 633                                         ERROR("Failed to encrypt directory \"%ls\"",
 634                                               path);
 635                                         win32_error(err);
 636                                         return WIMLIB_ERR_WRITE;
 637                                 }
 638                         }
 639                 } else {
 640                         ret = do_win32_extract_encrypted_stream(path, lte);
 641                         if (ret)
 642                                 return ret;
 643                         DEBUG("Extracted encrypted file \"%ls\"", path);
 644                 }
 645                 *creationDisposition_ret = OPEN_EXISTING;
 646         }
 647
 648         /* Set file attributes if we created the file.  Otherwise, we haven't
 649          * created the file set and we will set the attributes in the call to
 650          * CreateFileW().
 651          *
 652          * The FAT filesystem does not let you change the attributes of the root
 653          * directory, so treat that as a special case and do not set attributes.
 654          * */
 655         if (*creationDisposition_ret == OPEN_EXISTING &&
 656             !path_is_root_of_drive(path))
 657         {
 658                 if (!SetFileAttributesW(path,
 659                                         win32_mask_attributes(inode->i_attributes)))
 660                 {
 661                         err = GetLastError();
 662                         ERROR("Failed to set attributes on \"%ls\"", path);
 663                         win32_error(err);
 664                         return WIMLIB_ERR_WRITE;
 665                 }
 666         }
 667         return 0;
 668 }
 669
 670 /* Set security descriptor and extract stream data or reparse data (skip the
 671  * unnamed data stream of encrypted files, which was already extracted). */
 672 static int
 673 win32_finish_extract_stream(HANDLE h, const struct wim_dentry *dentry,
 674                             const struct wim_lookup_table_entry *lte,
 675                             const wchar_t *stream_path,
 676                             const wchar_t *stream_name_utf16,
 677                             struct apply_args *args)
 678 {
 679         int ret = 0;
 680         const struct wim_inode *inode = dentry->d_inode;
 681         if (stream_name_utf16 == NULL) {
 682                 /* Unnamed stream. */
 683
 684                 /* Set security descriptor, unless the extract_flags indicate
 685                  * not to or the volume does not supported it.  Note that this
 686                  * is only done when the unnamed stream is being extracted, as
 687                  * security descriptors are per-file and not per-stream. */
 688                 if (inode->i_security_id >= 0 &&
 689                     !(args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
 690                     && (args->vol_flags & FILE_PERSISTENT_ACLS))
 691                 {
 692                         ret = win32_set_security_data(inode, h, stream_path, args);
 693                         if (ret)
 694                                 return ret;
 695                 }
 696
 697                 /* Handle reparse points.  The data for them needs to be set
 698                  * using a special ioctl.  Note that the reparse point may have
 699                  * been created using CreateFileW() in the case of
 700                  * non-directories or CreateDirectoryW() in the case of
 701                  * directories; but the ioctl works either way.  Also, it is
 702                  * only this step that actually sets the
 703                  * FILE_ATTRIBUTE_REPARSE_POINT, as it is not valid to set it
 704                  * using SetFileAttributesW() or CreateFileW().
 705                  *
 706                  * If the volume does not support reparse points we simply
 707                  * ignore the reparse data.  (N.B. the code currently doesn't
 708                  * actually reach this case because reparse points are skipped
 709                  * entirely on such volumes.) */
 710                 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 711                         if (args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS) {
 712                                 ret = win32_set_reparse_data(h, inode,
 713                                                              lte, stream_path,
 714                                                              args);
 715                                 if (ret)
 716                                         return ret;
 717                         } else {
 718                                 DEBUG("Cannot set reparse data on \"%ls\": volume "
 719                                       "does not support reparse points", stream_path);
 720                         }
 721                 } else if (lte != NULL &&
 722                            !(args->vol_flags & FILE_SUPPORTS_ENCRYPTION &&
 723                              inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
 724                 {
 725                         /* Extract the data of the unnamed stream, unless the
 726                          * lookup table entry is NULL (indicating an empty
 727                          * stream for which no data needs to be extracted), or
 728                          * the stream is encrypted and therefore was already
 729                          * extracted as a special case. */
 730                         ret = do_win32_extract_stream(h, lte);
 731                         if (ret)
 732                                 return ret;
 733                 }
 734
 735                 if (dentry_has_short_name(dentry))
 736                         SetFileShortNameW(h, dentry->short_name);
 737                 else if (running_on_windows_7_or_later())
 738                         SetFileShortNameW(h, L"");
 739         } else {
 740                 /* Extract the data for a named data stream. */
 741                 if (lte != NULL) {
 742                         DEBUG("Extracting named data stream \"%ls\" (len = %"PRIu64")",
 743                               stream_path, wim_resource_size(lte));
 744                         ret = do_win32_extract_stream(h, lte);
 745                 }
 746         }
 747         return ret;
 748 }
 749
 750 static int
 751 win32_decrypt_file(HANDLE open_handle, const wchar_t *path)
 752 {
 753         DWORD err;
 754         /* We cannot call DecryptFileW() while there is an open handle to the
 755          * file.  So close it first. */
 756         if (!CloseHandle(open_handle)) {
 757                 err = GetLastError();
 758                 ERROR("Failed to close handle for \"%ls\"", path);
 759                 win32_error(err);
 760                 return WIMLIB_ERR_WRITE;
 761         }
 762         if (!DecryptFileW(path, 0 /* reserved parameter; set to 0 */)) {
 763                 err = GetLastError();
 764                 ERROR("Failed to decrypt file \"%ls\"", path);
 765                 win32_error(err);
 766                 return WIMLIB_ERR_WRITE;
 767         }
 768         return 0;
 769 }
 770
 771 /*
 772  * Create and extract a stream to a file, or create a directory, using the
 773  * Windows API.
 774  *
 775  * This handles reparse points, directories, alternate data streams, encrypted
 776  * files, compressed files, etc.
 777  *
 778  * @dentry: WIM dentry for the file or directory being extracted.
 779  *
 780  * @path:  Path to extract the file to.
 781  *
 782  * @stream_name_utf16:
 783  *         Name of the stream, or NULL if the stream is unnamed.  This will
 784  *         be called with a NULL stream_name_utf16 before any non-NULL
 785  *         stream_name_utf16's.
 786  *
 787  * @lte:   WIM lookup table entry for the stream.  May be NULL to indicate
 788  *         a stream of length 0.
 789  *
 790  * @args:  Additional apply context, including flags indicating supported
 791  *         volume features.
 792  *
 793  * Returns 0 on success; nonzero on failure.
 794  */
 795 static int
 796 win32_extract_stream(const struct wim_dentry *dentry,
 797                      const wchar_t *path,
 798                      const wchar_t *stream_name_utf16,
 799                      struct wim_lookup_table_entry *lte,
 800                      struct apply_args *args)
 801 {
 802         wchar_t *stream_path;
 803         HANDLE h;
 804         int ret;
 805         DWORD err;
 806         DWORD creationDisposition = CREATE_ALWAYS;
 807         DWORD requestedAccess;
 808         BY_HANDLE_FILE_INFORMATION file_info;
 809         unsigned remaining_sharing_violations = 1000;
 810         const struct wim_inode *inode = dentry->d_inode;
 811
 812         if (stream_name_utf16) {
 813                 /* Named stream.  Create a buffer that contains the UTF-16LE
 814                  * string [./]path:stream_name_utf16.  This is needed to
 815                  * create and open the stream using CreateFileW().  I'm not
 816                  * aware of any other APIs to do this.  Note: the '$DATA' suffix
 817                  * seems to be unneeded.  Additional note: a "./" prefix needs
 818                  * to be added when the path is not absolute to avoid ambiguity
 819                  * with drive letters. */
 820                 size_t stream_path_nchars;
 821                 size_t path_nchars;
 822                 size_t stream_name_nchars;
 823                 const wchar_t *prefix;
 824
 825                 path_nchars = wcslen(path);
 826                 stream_name_nchars = wcslen(stream_name_utf16);
 827                 stream_path_nchars = path_nchars + 1 + stream_name_nchars;
 828                 if (path[0] != cpu_to_le16(L'\0') &&
 829                     path[0] != cpu_to_le16(L'/') &&
 830                     path[0] != cpu_to_le16(L'\\') &&
 831                     path[1] != cpu_to_le16(L':'))
 832                 {
 833                         prefix = L"./";
 834                         stream_path_nchars += 2;
 835                 } else {
 836                         prefix = L"";
 837                 }
 838                 stream_path = alloca((stream_path_nchars + 1) * sizeof(wchar_t));
 839                 swprintf(stream_path, L"%ls%ls:%ls",
 840                          prefix, path, stream_name_utf16);
 841         } else {
 842                 /* Unnamed stream; its path is just the path to the file itself.
 843                  * */
 844                 stream_path = (wchar_t*)path;
 845
 846                 ret = win32_begin_extract_unnamed_stream(inode, lte, path,
 847                                                          &creationDisposition,
 848                                                          args->vol_flags);
 849                 if (ret)
 850                         goto fail;
 851         }
 852
 853         DEBUG("Opening \"%ls\"", stream_path);
 854         /* DELETE access is needed for SetFileShortNameW(), for some reason. */
 855         requestedAccess = GENERIC_READ | GENERIC_WRITE | DELETE |
 856                           ACCESS_SYSTEM_SECURITY;
 857 try_open_again:
 858         /* Open the stream to be extracted.  Depending on what we have set
 859          * creationDisposition to, we may be creating this for the first time,
 860          * or we may be opening on existing stream we already created using
 861          * CreateDirectoryW() or OpenEncryptedFileRawW(). */
 862         h = CreateFileW(stream_path,
 863                         requestedAccess,
 864                         FILE_SHARE_READ,
 865                         NULL,
 866                         creationDisposition,
 867                         win32_get_create_flags_and_attributes(inode->i_attributes),
 868                         NULL);
 869         if (h == INVALID_HANDLE_VALUE) {
 870                 err = GetLastError();
 871                 if (err == ERROR_ACCESS_DENIED &&
 872                     path_is_root_of_drive(stream_path))
 873                 {
 874                         ret = 0;
 875                         goto out;
 876                 }
 877                 if ((err == ERROR_PRIVILEGE_NOT_HELD ||
 878                      err == ERROR_ACCESS_DENIED) &&
 879                     (requestedAccess & ACCESS_SYSTEM_SECURITY))
 880                 {
 881                         /* Try opening the file again without privilege to
 882                          * modify SACL. */
 883                         requestedAccess &= ~ACCESS_SYSTEM_SECURITY;
 884                         goto try_open_again;
 885                 }
 886                 if (err == ERROR_SHARING_VIOLATION) {
 887                         if (remaining_sharing_violations) {
 888                                 --remaining_sharing_violations;
 889                                 /* This can happen when restoring encrypted directories
 890                                  * for some reason.  Probably a bug in EncryptFile(). */
 891                                 WARNING("Couldn't open \"%ls\" due to sharing violation; "
 892                                         "re-trying after 100ms", stream_path);
 893                                 Sleep(100);
 894                                 goto try_open_again;
 895                         } else {
 896                                 ERROR("Too many sharing violations; giving up...");
 897                         }
 898                 } else {
 899                         if (creationDisposition == OPEN_EXISTING)
 900                                 ERROR("Failed to open \"%ls\"", stream_path);
 901                         else
 902                                 ERROR("Failed to create \"%ls\"", stream_path);
 903                         win32_error(err);
 904                 }
 905                 ret = WIMLIB_ERR_OPEN;
 906                 goto fail;
 907         }
 908
 909         /* Check the attributes of the file we just opened, and remove
 910          * encryption or compression if either was set by default but is not
 911          * supposed to be set based on the WIM inode attributes. */
 912         if (!GetFileInformationByHandle(h, &file_info)) {
 913                 err = GetLastError();
 914                 ERROR("Failed to get attributes of \"%ls\"", stream_path);
 915                 win32_error(err);
 916                 ret = WIMLIB_ERR_STAT;
 917                 goto fail_close_handle;
 918         }
 919
 920         /* Remove encryption? */
 921         if (file_info.dwFileAttributes & FILE_ATTRIBUTE_ENCRYPTED &&
 922             !(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
 923         {
 924                 /* File defaulted to encrypted due to being in an encrypted
 925                  * directory, but is not actually supposed to be encrypted.
 926                  *
 927                  * This is a workaround, because I'm not aware of any way to
 928                  * directly (e.g. with CreateFileW()) create an unencrypted file
 929                  * in a directory with FILE_ATTRIBUTE_ENCRYPTED set. */
 930                 ret = win32_decrypt_file(h, stream_path);
 931                 if (ret)
 932                         goto fail; /* win32_decrypt_file() closed the handle. */
 933                 creationDisposition = OPEN_EXISTING;
 934                 goto try_open_again;
 935         }
 936
 937         /* Remove compression? */
 938         if (file_info.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED &&
 939             !(inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED))
 940         {
 941                 /* Similar to the encrypted case, above, if the file defaulted
 942                  * to compressed due to being in an compressed directory, but is
 943                  * not actually supposed to be compressed, explicitly set the
 944                  * compression format to COMPRESSION_FORMAT_NONE. */
 945                 ret = win32_set_compression_state(h, COMPRESSION_FORMAT_NONE,
 946                                                   stream_path);
 947                 if (ret)
 948                         goto fail_close_handle;
 949         }
 950
 951         /* Set compression and/or sparse attributes if needed */
 952         ret = win32_set_special_stream_attributes(h, inode, lte, path,
 953                                                   args->vol_flags);
 954
 955         if (ret)
 956                 goto fail_close_handle;
 957
 958         /* At this point we have at least created the needed stream with the
 959          * appropriate attributes.  We have yet to set the appropriate security
 960          * descriptor and actually extract the stream data (other than for
 961          * extracted files, which were already extracted).
 962          * win32_finish_extract_stream() handles these additional steps. */
 963         ret = win32_finish_extract_stream(h, dentry, lte, stream_path,
 964                                           stream_name_utf16, args);
 965         if (ret)
 966                 goto fail_close_handle;
 967
 968         /* Done extracting the stream.  Close the handle and return. */
 969         DEBUG("Closing \"%ls\"", stream_path);
 970         if (!CloseHandle(h)) {
 971                 err = GetLastError();
 972                 ERROR("Failed to close \"%ls\"", stream_path);
 973                 win32_error(err);
 974                 ret = WIMLIB_ERR_WRITE;
 975                 goto fail;
 976         }
 977         ret = 0;
 978         goto out;
 979 fail_close_handle:
 980         CloseHandle(h);
 981 fail:
 982         ERROR("Error extracting \"%ls\"", stream_path);
 983 out:
 984         return ret;
 985 }
 986
 987 /*
 988  * Creates a file, directory, or reparse point and extracts all streams to it
 989  * (unnamed data stream and/or reparse point stream, plus any alternate data
 990  * streams).  Handles sparse, compressed, and/or encrypted files.
 991  *
 992  * @dentry:     WIM dentry for this file or directory.
 993  * @path:       UTF-16LE external path to extract the inode to.
 994  * @args:       Additional extraction context.
 995  *
 996  * Returns 0 on success; nonzero on failure.
 997  */
 998 static int
 999 win32_extract_streams(const struct wim_dentry *dentry,
1000                       const wchar_t *path, struct apply_args *args)
1001 {
1002         struct wim_lookup_table_entry *unnamed_lte;
1003         int ret;
1004         const struct wim_inode *inode = dentry->d_inode;
1005
1006         /* First extract the unnamed stream. */
1007
1008         unnamed_lte = inode_unnamed_lte_resolved(inode);
1009         ret = win32_extract_stream(dentry, path, NULL, unnamed_lte, args);
1010         if (ret)
1011                 goto out;
1012
1013         /* Extract any named streams, if supported by the volume. */
1014
1015         if (!(args->vol_flags & FILE_NAMED_STREAMS))
1016                 goto out;
1017         for (u16 i = 0; i < inode->i_num_ads; i++) {
1018                 const struct wim_ads_entry *ads_entry = &inode->i_ads_entries[i];
1019
1020                 /* Skip the unnamed stream if it's in the ADS entries (we
1021                  * already extracted it...) */
1022                 if (ads_entry->stream_name_nbytes == 0)
1023                         continue;
1024
1025                 /* Skip special UNIX data entries (see documentation for
1026                  * WIMLIB_ADD_FLAG_UNIX_DATA) */
1027                 if (ads_entry->stream_name_nbytes == WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES
1028                     && !memcmp(ads_entry->stream_name,
1029                                WIMLIB_UNIX_DATA_TAG_UTF16LE,
1030                                WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES))
1031                         continue;
1032
1033                 /* Extract the named stream */
1034                 ret = win32_extract_stream(dentry,
1035                                            path,
1036                                            ads_entry->stream_name,
1037                                            ads_entry->lte,
1038                                            args);
1039                 if (ret)
1040                         break;
1041         }
1042 out:
1043         return ret;
1044 }
1045
1046 static int
1047 dentry_clear_inode_visited(struct wim_dentry *dentry, void *_ignore)
1048 {
1049         dentry->d_inode->i_visited = 0;
1050         return 0;
1051 }
1052
1053 static int
1054 dentry_get_features(struct wim_dentry *dentry, void *_features_p)
1055 {
1056         DWORD features = 0;
1057         DWORD *features_p = _features_p;
1058         struct wim_inode *inode = dentry->d_inode;
1059
1060         if (inode->i_visited) {
1061                 features |= FILE_SUPPORTS_HARD_LINKS;
1062         } else {
1063                 inode->i_visited = 1;
1064                 if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE)
1065                         features |= FILE_SUPPORTS_SPARSE_FILES;
1066                 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)
1067                         features |= FILE_SUPPORTS_REPARSE_POINTS;
1068                 for (unsigned i = 0; i < inode->i_num_ads; i++)
1069                         if (inode->i_ads_entries[i].stream_name_nbytes)
1070                                 features |= FILE_NAMED_STREAMS;
1071                 if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED)
1072                         features |= FILE_SUPPORTS_ENCRYPTION;
1073                 if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED)
1074                         features |= FILE_FILE_COMPRESSION;
1075                 if (inode->i_security_id != -1)
1076                         features |= FILE_PERSISTENT_ACLS;
1077         }
1078         *features_p |= features;
1079         return 0;
1080 }
1081
1082 /* If not done already, load the supported feature flags for the volume onto
1083  * which the image is being extracted, and warn the user about any missing
1084  * features that could be important. */
1085 static int
1086 win32_check_vol_flags(const wchar_t *output_path,
1087                       struct wim_dentry *root, struct apply_args *args)
1088 {
1089         DWORD dentry_features = 0;
1090         DWORD missing_features;
1091
1092         if (args->have_vol_flags)
1093                 return 0;
1094
1095         for_dentry_in_tree(root, dentry_clear_inode_visited, NULL);
1096         for_dentry_in_tree(root, dentry_get_features, &dentry_features);
1097
1098         win32_get_vol_flags(output_path, &args->vol_flags);
1099         args->have_vol_flags = true;
1100
1101         missing_features = dentry_features & ~args->vol_flags;
1102
1103         /* Warn the user about data that may not be extracted. */
1104         if (missing_features & FILE_SUPPORTS_SPARSE_FILES)
1105                 WARNING("Volume does not support sparse files!\n"
1106                         "          Sparse files will be extracted as non-sparse.");
1107         if (missing_features & FILE_SUPPORTS_REPARSE_POINTS)
1108                 WARNING("Volume does not support reparse points!\n"
1109                         "          Reparse point data will not be extracted.");
1110         if (missing_features & FILE_NAMED_STREAMS) {
1111                 WARNING("Volume does not support named data streams!\n"
1112                         "          Named data streams will not be extracted.");
1113         }
1114         if (missing_features & FILE_SUPPORTS_ENCRYPTION) {
1115                 WARNING("Volume does not support encryption!\n"
1116                         "          Encrypted files will be extracted as raw data.");
1117         }
1118         if (missing_features & FILE_FILE_COMPRESSION) {
1119                 WARNING("Volume does not support transparent compression!\n"
1120                         "          Compressed files will be extracted as non-compressed.");
1121         }
1122         if (missing_features & FILE_PERSISTENT_ACLS) {
1123                 if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
1124                         ERROR("Strict ACLs requested, but the volume does not "
1125                               "support ACLs!");
1126                         return WIMLIB_ERR_VOLUME_LACKS_FEATURES;
1127                 } else {
1128                         WARNING("Volume does not support persistent ACLS!\n"
1129                                 "          File permissions will not be extracted.");
1130                 }
1131         }
1132         if (running_on_windows_7_or_later() &&
1133             (missing_features & FILE_SUPPORTS_HARD_LINKS))
1134         {
1135                 WARNING("Volume does not support hard links!\n"
1136                         "          Hard links will be extracted as duplicate files.");
1137         }
1138         return 0;
1139 }
1140
1141 /*
1142  * Try extracting a hard link.
1143  *
1144  * @output_path:  Path to link to be extracted.
1145  *
1146  * @inode:        WIM inode that the link is to; inode->i_extracted_file
1147  *                the path to a name of the file that has already been
1148  *                extracted (we use this to create the hard link).
1149  *
1150  * @args:         Additional apply context, used here to keep track of
1151  *                the number of times creating a hard link failed due to
1152  *                ERROR_INVALID_FUNCTION.  This error should indicate that hard
1153  *                links are not supported by the volume, and we would like to
1154  *                warn the user a few times, but not too many times.
1155  *
1156  * Returns 0 if the hard link was successfully extracted.  Returns
1157  * WIMLIB_ERR_LINK (> 0) if an error occurred, other than hard links possibly
1158  * being unsupported by the volume.  Returns a negative value if creating the
1159  * hard link failed due to ERROR_INVALID_FUNCTION.
1160  */
1161 static int
1162 win32_try_hard_link(const wchar_t *output_path, const struct wim_inode *inode,
1163                     struct apply_args *args)
1164 {
1165         DWORD err;
1166
1167         /* There is a volume flag for this (FILE_SUPPORTS_HARD_LINKS),
1168          * but it's only available on Windows 7 and later.
1169          *
1170          * Otherwise, CreateHardLinkW() will apparently return
1171          * ERROR_INVALID_FUNCTION if the volume does not support hard links. */
1172
1173         DEBUG("Creating hard link \"%ls => %ls\"",
1174               output_path, inode->i_extracted_file);
1175
1176         if (running_on_windows_7_or_later() &&
1177             !(args->vol_flags & FILE_SUPPORTS_HARD_LINKS))
1178                 goto hard_links_unsupported;
1179
1180         if (CreateHardLinkW(output_path, inode->i_extracted_file, NULL))
1181                 return 0;
1182
1183         err = GetLastError();
1184         if (err != ERROR_INVALID_FUNCTION) {
1185                 ERROR("Can't create hard link \"%ls => %ls\"",
1186                       output_path, inode->i_extracted_file);
1187                 win32_error(err);
1188                 return WIMLIB_ERR_LINK;
1189         }
1190 hard_links_unsupported:
1191         args->num_hard_links_failed++;
1192         if (args->num_hard_links_failed <= MAX_CREATE_HARD_LINK_WARNINGS) {
1193                 if (running_on_windows_7_or_later())
1194                 {
1195                         WARNING("Extracting duplicate copy of \"%ls\" "
1196                                 "rather than hard link", output_path);
1197                 } else {
1198                         WARNING("Can't create hard link \"%ls\" => \"%ls\":\n"
1199                                 "          Volume does not support hard links!\n"
1200                                 "          Falling back to extracting a copy of the file.",
1201                                 output_path, inode->i_extracted_file);
1202                 }
1203         }
1204         if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS)
1205                 WARNING("Suppressing further hard linking warnings...");
1206         return -1;
1207 }
1208
1209 /* Extract a file, directory, reparse point, or hard link to an
1210  * already-extracted file using the Win32 API */
1211 int
1212 win32_do_apply_dentry(const wchar_t *output_path,
1213                       size_t output_path_num_chars,
1214                       struct wim_dentry *dentry,
1215                       struct apply_args *args)
1216 {
1217         int ret;
1218         struct wim_inode *inode = dentry->d_inode;
1219
1220         ret = win32_check_vol_flags(output_path, dentry, args);
1221         if (ret)
1222                 return ret;
1223         if (inode->i_nlink > 1 && inode->i_extracted_file != NULL) {
1224                 /* Linked file, with another name already extracted.  Create a
1225                  * hard link. */
1226                 ret = win32_try_hard_link(output_path, inode, args);
1227                 if (ret >= 0)
1228                         return ret;
1229                 /* Negative return value from win32_try_hard_link() indicates
1230                  * that hard links are probably not supported by the volume.
1231                  * Fall back to extracting a copy of the file. */
1232         }
1233
1234         /* If this is a reparse point and the volume does not support reparse
1235          * points, just skip it completely. */
1236         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
1237             !(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
1238         {
1239                 WARNING("Not extracting reparse point \"%ls\"", output_path);
1240         } else {
1241                 /* Create the file, directory, or reparse point, and extract the
1242                  * data streams. */
1243                 ret = win32_extract_streams(dentry, output_path, args);
1244                 if (ret)
1245                         return ret;
1246         }
1247         if (inode->i_extracted_file == NULL) {
1248                 const struct wim_lookup_table_entry *lte;
1249
1250                 /* Tally bytes extracted, including all alternate data streams,
1251                  * unless we extracted a hard link (or, at least extracted a
1252                  * name that was supposed to be a hard link) */
1253                 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1254                         lte = inode_stream_lte_resolved(inode, i);
1255                         if (lte)
1256                                 args->progress.extract.completed_bytes +=
1257                                                         wim_resource_size(lte);
1258                 }
1259                 if (inode->i_nlink > 1) {
1260                         /* Save extracted path for a later call to
1261                          * CreateHardLinkW() if this inode has multiple links.
1262                          * */
1263                         inode->i_extracted_file = WSTRDUP(output_path);
1264                         if (!inode->i_extracted_file)
1265                                 return WIMLIB_ERR_NOMEM;
1266                 }
1267         }
1268         return 0;
1269 }
1270
1271 /* Set timestamps on an extracted file using the Win32 API */
1272 int
1273 win32_do_apply_dentry_timestamps(const wchar_t *path,
1274                                  size_t path_num_chars,
1275                                  struct wim_dentry *dentry,
1276                                  struct apply_args *args)
1277 {
1278         DWORD err;
1279         HANDLE h;
1280         const struct wim_inode *inode = dentry->d_inode;
1281
1282         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
1283             !(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
1284         {
1285                 /* Skip reparse points not extracted */
1286                 return 0;
1287         }
1288
1289         /* Windows doesn't let you change the timestamps of the root directory
1290          * (at least on FAT, which is dumb but expected since FAT doesn't store
1291          * any metadata about the root directory...) */
1292         if (path_is_root_of_drive(path))
1293                 return 0;
1294
1295         DEBUG("Opening \"%ls\" to set timestamps", path);
1296         h = win32_open_existing_file(path, FILE_WRITE_ATTRIBUTES);
1297         if (h == INVALID_HANDLE_VALUE) {
1298                 err = GetLastError();
1299                 goto fail;
1300         }
1301
1302         FILETIME creationTime = {.dwLowDateTime = inode->i_creation_time & 0xffffffff,
1303                                  .dwHighDateTime = inode->i_creation_time >> 32};
1304         FILETIME lastAccessTime = {.dwLowDateTime = inode->i_last_access_time & 0xffffffff,
1305                                   .dwHighDateTime = inode->i_last_access_time >> 32};
1306         FILETIME lastWriteTime = {.dwLowDateTime = inode->i_last_write_time & 0xffffffff,
1307                                   .dwHighDateTime = inode->i_last_write_time >> 32};
1308
1309         DEBUG("Calling SetFileTime() on \"%ls\"", path);
1310         if (!SetFileTime(h, &creationTime, &lastAccessTime, &lastWriteTime)) {
1311                 err = GetLastError();
1312                 CloseHandle(h);
1313                 goto fail;
1314         }
1315         DEBUG("Closing \"%ls\"", path);
1316         if (!CloseHandle(h)) {
1317                 err = GetLastError();
1318                 goto fail;
1319         }
1320         goto out;
1321 fail:
1322         /* Only warn if setting timestamps failed; still return 0. */
1323         WARNING("Can't set timestamps on \"%ls\"", path);
1324         win32_error(err);
1325 out:
1326         return 0;
1327 }
1328
1329 #endif /* __WIN32__ */