2 * win32_apply.c - Windows-specific code for applying files from a WIM image.
6 * Copyright (C) 2013 Eric Biggers
8 * This file is part of wimlib, a library for working with WIM files.
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)
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
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/.
30 #include <aclapi.h> /* for SetSecurityInfo() */
32 #include "wimlib/win32_common.h"
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"
43 #define MAX_CREATE_HARD_LINK_WARNINGS 5
44 #define MAX_CREATE_SOFT_LINK_WARNINGS 5
46 #define MAX_SET_SD_ACCESS_DENIED_WARNINGS 1
47 #define MAX_SET_SACL_PRIV_NOTHELD_WARNINGS 1
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"
59 win32_extract_try_rpfix(u8 *rpbuf,
61 const wchar_t *extract_root_realpath,
62 unsigned extract_root_realpath_nchars)
64 struct reparse_data rpdata;
67 size_t stripped_nchars;
68 wchar_t *stripped_target;
69 wchar_t stripped_target_nchars;
72 utf16lechar *new_target;
73 utf16lechar *new_print_name;
74 size_t new_target_nchars;
75 size_t new_print_name_nchars;
78 ret = parse_reparse_data(rpbuf, *rpbuflen_p, &rpdata);
82 if (extract_root_realpath[0] == L'\0' ||
83 extract_root_realpath[1] != L':' ||
84 extract_root_realpath[2] != L'\\')
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;
92 ret = parse_substitute_name(rpdata.substitute_name,
93 rpdata.substitute_name_nbytes,
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;
103 new_target = alloca((6 + extract_root_realpath_nchars +
104 stripped_target_nchars) * sizeof(utf16lechar));
107 if (stripped_nchars == 6) {
108 /* Include \??\ prefix if it was present before */
109 p = wmempcpy(p, L"\\??\\", 4);
112 /* Print name excludes the \??\ if present. */
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];
120 /* Copy the rest of the extract root */
121 p = wmempcpy(p, extract_root_realpath + 2, extract_root_realpath_nchars - 2);
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;
128 if (new_target_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE ||
129 new_print_name_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE)
131 ERROR("Path names too long to do reparse point fixup!");
132 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
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);
141 /* Wrapper around the FSCTL_SET_REPARSE_POINT ioctl to set the reparse data on
142 * an extracted reparse point. */
144 win32_set_reparse_data(HANDLE h,
145 const struct wim_inode *inode,
146 const struct wim_lookup_table_entry *lte,
148 struct apply_args *args)
151 u8 rpbuf[REPARSE_POINT_MAX_SIZE] _aligned_attribute(8);
155 DEBUG("Setting reparse data on \"%ls\"", path);
157 ret = wim_inode_get_reparse_data(inode, rpbuf, &rpbuflen);
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)
166 ret = win32_extract_try_rpfix(rpbuf,
168 args->target_realpath,
169 args->target_realpath_len);
171 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
174 /* Set the reparse data on the open file using the
175 * FSCTL_SET_REPARSE_POINT ioctl.
177 * There are contradictions in Microsoft's documentation for this:
179 * "If hDevice was opened without specifying FILE_FLAG_OVERLAPPED,
180 * lpOverlapped is ignored."
182 * --- So setting lpOverlapped to NULL is okay since it's ignored.
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."
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:
193 * "Not used with this operation; set to NULL."
195 if (!DeviceIoControl(h, FSCTL_SET_REPARSE_POINT, rpbuf,
198 &bytesReturned /* lpBytesReturned */,
199 NULL /* lpOverlapped */))
201 DWORD err = GetLastError();
202 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
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 "
209 " SeCreateSymbolicLink privilege, which by "
210 "default non-Administrator\n"
211 " accounts do not have.", path);
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...");
218 ERROR("Failed to set reparse data on \"%ls\"", path);
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;
224 return WIMLIB_ERR_WRITE;
230 /* Wrapper around the FSCTL_SET_COMPRESSION ioctl to change the
231 * FILE_ATTRIBUTE_COMPRESSED flag of a file or directory. */
233 win32_set_compression_state(HANDLE hFile, USHORT format, const wchar_t *path)
236 if (!DeviceIoControl(hFile, FSCTL_SET_COMPRESSION,
237 &format, sizeof(USHORT),
239 &bytesReturned, NULL))
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);
246 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
247 return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
249 return WIMLIB_ERR_WRITE;
254 /* Wrapper around FSCTL_SET_SPARSE ioctl to set a file as sparse. */
256 win32_set_sparse(HANDLE hFile, const wchar_t *path)
259 if (!DeviceIoControl(hFile, FSCTL_SET_SPARSE,
262 &bytesReturned, NULL))
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);
269 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
270 return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
272 return WIMLIB_ERR_WRITE;
278 * Sets the security descriptor on an extracted file.
281 win32_set_security_data(const struct wim_inode *inode,
284 struct apply_args *args)
286 PSECURITY_DESCRIPTOR descriptor;
289 const struct wim_security_data *sd;
291 SECURITY_INFORMATION securityInformation = 0;
298 BOOL owner_defaulted;
299 BOOL group_defaulted;
305 sd = wim_const_security_data(args->w);
306 descriptor = sd->descriptors[inode->i_security_id];
308 GetSecurityDescriptorOwner(descriptor, &owner, &owner_defaulted);
310 securityInformation |= OWNER_SECURITY_INFORMATION;
312 GetSecurityDescriptorGroup(descriptor, &group, &group_defaulted);
314 securityInformation |= GROUP_SECURITY_INFORMATION;
316 GetSecurityDescriptorDacl(descriptor, &dacl_present,
317 &dacl, &dacl_defaulted);
319 securityInformation |= DACL_SECURITY_INFORMATION;
321 GetSecurityDescriptorSacl(descriptor, &sacl_present,
322 &sacl, &sacl_defaulted);
324 securityInformation |= SACL_SECURITY_INFORMATION;
327 if (securityInformation == 0)
329 if (SetSecurityInfo(hFile, SE_FILE_OBJECT,
330 securityInformation, owner, group, dacl, sacl))
332 err = GetLastError();
333 if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
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;
341 if (n < MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
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)
348 WARNING("%ls", apply_access_denied_msg);
350 WARNING("Re-trying with SACL omitted.\n", path);
351 } else if (n == MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
353 "Suppressing further 'privileges not held' error messages when setting\n"
354 " security descriptors.");
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)
368 WARNING("%ls", apply_access_denied_msg);
370 } else if (n == MAX_SET_SD_ACCESS_DENIED_WARNINGS) {
372 "Suppressing further access denied error messages when setting\n"
373 " security descriptors");
378 ERROR("Failed to set security descriptor on \"%ls\"", path);
380 if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
381 return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
383 return WIMLIB_ERR_WRITE;
389 win32_extract_chunk(const void *buf, size_t len, void *arg)
391 HANDLE hStream = arg;
393 DWORD nbytes_written;
394 wimlib_assert(len <= 0xffffffff);
396 if (!WriteFile(hStream, buf, len, &nbytes_written, NULL) ||
397 nbytes_written != len)
399 DWORD err = GetLastError();
400 ERROR("WriteFile(): write error");
402 return WIMLIB_ERR_WRITE;
408 do_win32_extract_stream(HANDLE hStream, const struct wim_lookup_table_entry *lte)
410 return extract_wim_resource(lte, wim_resource_size(lte),
411 win32_extract_chunk, hStream);
414 struct win32_encrypted_extract_ctx {
415 const struct wim_lookup_table_entry *lte;
420 win32_encrypted_import_cb(unsigned char *data, void *_ctx,
421 unsigned long *len_p)
423 struct win32_encrypted_extract_ctx *ctx = _ctx;
424 unsigned long len = *len_p;
425 const struct wim_lookup_table_entry *lte = ctx->lte;
427 len = min(len, wim_resource_size(lte) - ctx->offset);
429 if (read_partial_wim_resource_into_buf(lte, len, ctx->offset, data))
430 return ERROR_READ_FAULT;
434 return ERROR_SUCCESS;
437 /* Create an encrypted file and extract the raw encrypted data to it.
439 * @path: Path to encrypted file to create.
440 * @lte: WIM lookup_table entry for the raw encrypted data.
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().
447 * Returns 0 on success; nonzero on failure.
450 do_win32_extract_encrypted_stream(const wchar_t *path,
451 const struct wim_lookup_table_entry *lte)
456 DEBUG("Opening file \"%ls\" to extract raw encrypted data", path);
458 ret = OpenEncryptedFileRawW(path, CREATE_FOR_IMPORT, &file_ctx);
460 ERROR("Failed to open \"%ls\" to write raw encrypted data", path);
462 return WIMLIB_ERR_OPEN;
466 struct win32_encrypted_extract_ctx ctx;
470 ret = WriteEncryptedFileRaw(win32_encrypted_import_cb, &ctx, file_ctx);
471 if (ret == ERROR_SUCCESS) {
474 ret = WIMLIB_ERR_WRITE;
475 ERROR("Failed to extract encrypted file \"%ls\"", path);
478 CloseEncryptedFileRaw(file_ctx);
483 path_is_root_of_drive(const wchar_t *path)
488 if (*path != L'/' && *path != L'\\') {
489 if (*(path + 1) == L':')
494 while (*path == L'/' || *path == L'\\')
496 return (*path == L'\0');
500 win32_mask_attributes(DWORD i_attributes)
502 return i_attributes & ~(FILE_ATTRIBUTE_SPARSE_FILE |
503 FILE_ATTRIBUTE_COMPRESSED |
504 FILE_ATTRIBUTE_REPARSE_POINT |
505 FILE_ATTRIBUTE_DIRECTORY |
506 FILE_ATTRIBUTE_ENCRYPTED |
507 FILE_FLAG_DELETE_ON_CLOSE |
508 FILE_FLAG_NO_BUFFERING |
509 FILE_FLAG_OPEN_NO_RECALL |
510 FILE_FLAG_OVERLAPPED |
511 FILE_FLAG_RANDOM_ACCESS |
512 /*FILE_FLAG_SESSION_AWARE |*/
513 FILE_FLAG_SEQUENTIAL_SCAN |
514 FILE_FLAG_WRITE_THROUGH);
518 win32_get_create_flags_and_attributes(DWORD i_attributes)
521 * Some attributes cannot be set by passing them to CreateFile(). In
524 * FILE_ATTRIBUTE_DIRECTORY:
525 * CreateDirectory() must be called instead of CreateFile().
527 * FILE_ATTRIBUTE_SPARSE_FILE:
529 * See: win32_set_sparse().
531 * FILE_ATTRIBUTE_COMPRESSED:
532 * Not clear from the documentation, but apparently this needs an
534 * See: win32_set_compressed().
536 * FILE_ATTRIBUTE_REPARSE_POINT:
537 * Needs an ioctl, with the reparse data specified.
538 * See: win32_set_reparse_data().
540 * In addition, clear any file flags in the attributes that we don't
541 * want, but also specify FILE_FLAG_OPEN_REPARSE_POINT and
542 * FILE_FLAG_BACKUP_SEMANTICS as we are a backup application.
544 return win32_mask_attributes(i_attributes) |
545 FILE_FLAG_OPEN_REPARSE_POINT |
546 FILE_FLAG_BACKUP_SEMANTICS;
549 /* Set compression and/or sparse attributes on a stream, if supported by the
552 win32_set_special_stream_attributes(HANDLE hFile, const struct wim_inode *inode,
553 struct wim_lookup_table_entry *unnamed_stream_lte,
554 const wchar_t *path, unsigned vol_flags)
558 if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
559 if (vol_flags & FILE_FILE_COMPRESSION) {
560 ret = win32_set_compression_state(hFile,
561 COMPRESSION_FORMAT_DEFAULT,
566 DEBUG("Cannot set compression attribute on \"%ls\": "
567 "volume does not support transparent compression",
572 if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE) {
573 if (vol_flags & FILE_SUPPORTS_SPARSE_FILES) {
574 DEBUG("Setting sparse flag on \"%ls\"", path);
575 ret = win32_set_sparse(hFile, path);
579 DEBUG("Cannot set sparse attribute on \"%ls\": "
580 "volume does not support sparse files",
587 /* Pre-create directories; extract encrypted streams */
589 win32_begin_extract_unnamed_stream(const struct wim_inode *inode,
590 const struct wim_lookup_table_entry *lte,
592 DWORD *creationDisposition_ret,
593 unsigned int vol_flags)
598 /* Directories must be created with CreateDirectoryW(). Then the call
599 * to CreateFileW() will merely open the directory that was already
600 * created rather than creating a new file. */
601 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY &&
602 !path_is_root_of_drive(path)) {
603 if (!CreateDirectoryW(path, NULL)) {
604 err = GetLastError();
605 if (err != ERROR_ALREADY_EXISTS) {
606 ERROR("Failed to create directory \"%ls\"",
609 return WIMLIB_ERR_MKDIR;
612 DEBUG("Created directory \"%ls\"", path);
613 *creationDisposition_ret = OPEN_EXISTING;
615 if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED &&
616 vol_flags & FILE_SUPPORTS_ENCRYPTION)
618 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
619 unsigned remaining_sharing_violations = 100;
620 while (!EncryptFile(path)) {
621 if (remaining_sharing_violations &&
622 err == ERROR_SHARING_VIOLATION)
624 WARNING("Couldn't encrypt directory \"%ls\" "
625 "due to sharing violation; re-trying "
626 "after 100 ms", path);
628 remaining_sharing_violations--;
630 err = GetLastError();
631 ERROR("Failed to encrypt directory \"%ls\"",
634 return WIMLIB_ERR_WRITE;
638 ret = do_win32_extract_encrypted_stream(path, lte);
641 DEBUG("Extracted encrypted file \"%ls\"", path);
643 *creationDisposition_ret = OPEN_EXISTING;
646 /* Set file attributes if we created the file. Otherwise, we haven't
647 * created the file set and we will set the attributes in the call to
650 * The FAT filesystem does not let you change the attributes of the root
651 * directory, so treat that as a special case and do not set attributes.
653 if (*creationDisposition_ret == OPEN_EXISTING &&
654 !path_is_root_of_drive(path))
656 if (!SetFileAttributesW(path,
657 win32_mask_attributes(inode->i_attributes)))
659 err = GetLastError();
660 ERROR("Failed to set attributes on \"%ls\"", path);
662 return WIMLIB_ERR_WRITE;
668 /* Set security descriptor and extract stream data or reparse data (skip the
669 * unnamed data stream of encrypted files, which was already extracted). */
671 win32_finish_extract_stream(HANDLE h, const struct wim_dentry *dentry,
672 const struct wim_lookup_table_entry *lte,
673 const wchar_t *stream_path,
674 const wchar_t *stream_name_utf16,
675 struct apply_args *args)
678 const struct wim_inode *inode = dentry->d_inode;
679 if (stream_name_utf16 == NULL) {
680 /* Unnamed stream. */
682 /* Set security descriptor, unless the extract_flags indicate
683 * not to or the volume does not supported it. Note that this
684 * is only done when the unnamed stream is being extracted, as
685 * security descriptors are per-file and not per-stream. */
686 if (inode->i_security_id >= 0 &&
687 !(args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
688 && (args->vol_flags & FILE_PERSISTENT_ACLS))
690 ret = win32_set_security_data(inode, h, stream_path, args);
695 /* Handle reparse points. The data for them needs to be set
696 * using a special ioctl. Note that the reparse point may have
697 * been created using CreateFileW() in the case of
698 * non-directories or CreateDirectoryW() in the case of
699 * directories; but the ioctl works either way. Also, it is
700 * only this step that actually sets the
701 * FILE_ATTRIBUTE_REPARSE_POINT, as it is not valid to set it
702 * using SetFileAttributesW() or CreateFileW().
704 * If the volume does not support reparse points we simply
705 * ignore the reparse data. (N.B. the code currently doesn't
706 * actually reach this case because reparse points are skipped
707 * entirely on such volumes.) */
708 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
709 if (args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS) {
710 ret = win32_set_reparse_data(h, inode,
716 DEBUG("Cannot set reparse data on \"%ls\": volume "
717 "does not support reparse points", stream_path);
719 } else if (lte != NULL &&
720 !(args->vol_flags & FILE_SUPPORTS_ENCRYPTION &&
721 inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
723 /* Extract the data of the unnamed stream, unless the
724 * lookup table entry is NULL (indicating an empty
725 * stream for which no data needs to be extracted), or
726 * the stream is encrypted and therefore was already
727 * extracted as a special case. */
728 ret = do_win32_extract_stream(h, lte);
733 if (dentry_has_short_name(dentry))
734 SetFileShortNameW(h, dentry->short_name);
735 else if (running_on_windows_7_or_later())
736 SetFileShortNameW(h, L"");
738 /* Extract the data for a named data stream. */
740 DEBUG("Extracting named data stream \"%ls\" (len = %"PRIu64")",
741 stream_path, wim_resource_size(lte));
742 ret = do_win32_extract_stream(h, lte);
749 win32_decrypt_file(HANDLE open_handle, const wchar_t *path)
752 /* We cannot call DecryptFileW() while there is an open handle to the
753 * file. So close it first. */
754 if (!CloseHandle(open_handle)) {
755 err = GetLastError();
756 ERROR("Failed to close handle for \"%ls\"", path);
758 return WIMLIB_ERR_WRITE;
760 if (!DecryptFileW(path, 0 /* reserved parameter; set to 0 */)) {
761 err = GetLastError();
762 ERROR("Failed to decrypt file \"%ls\"", path);
764 return WIMLIB_ERR_WRITE;
770 * Create and extract a stream to a file, or create a directory, using the
773 * This handles reparse points, directories, alternate data streams, encrypted
774 * files, compressed files, etc.
776 * @dentry: WIM dentry for the file or directory being extracted.
778 * @path: Path to extract the file to.
780 * @stream_name_utf16:
781 * Name of the stream, or NULL if the stream is unnamed. This will
782 * be called with a NULL stream_name_utf16 before any non-NULL
783 * stream_name_utf16's.
785 * @lte: WIM lookup table entry for the stream. May be NULL to indicate
786 * a stream of length 0.
788 * @args: Additional apply context, including flags indicating supported
791 * Returns 0 on success; nonzero on failure.
794 win32_extract_stream(const struct wim_dentry *dentry,
796 const wchar_t *stream_name_utf16,
797 struct wim_lookup_table_entry *lte,
798 struct apply_args *args)
800 wchar_t *stream_path;
804 DWORD creationDisposition = CREATE_ALWAYS;
805 DWORD requestedAccess;
806 BY_HANDLE_FILE_INFORMATION file_info;
807 unsigned remaining_sharing_violations = 1000;
808 const struct wim_inode *inode = dentry->d_inode;
810 if (stream_name_utf16) {
811 /* Named stream. Create a buffer that contains the UTF-16LE
812 * string [./]path:stream_name_utf16. This is needed to
813 * create and open the stream using CreateFileW(). I'm not
814 * aware of any other APIs to do this. Note: the '$DATA' suffix
815 * seems to be unneeded. Additional note: a "./" prefix needs
816 * to be added when the path is not absolute to avoid ambiguity
817 * with drive letters. */
818 size_t stream_path_nchars;
820 size_t stream_name_nchars;
821 const wchar_t *prefix;
823 path_nchars = wcslen(path);
824 stream_name_nchars = wcslen(stream_name_utf16);
825 stream_path_nchars = path_nchars + 1 + stream_name_nchars;
826 if (path[0] != cpu_to_le16(L'\0') &&
827 path[0] != cpu_to_le16(L'/') &&
828 path[0] != cpu_to_le16(L'\\') &&
829 path[1] != cpu_to_le16(L':'))
832 stream_path_nchars += 2;
836 stream_path = alloca((stream_path_nchars + 1) * sizeof(wchar_t));
837 swprintf(stream_path, L"%ls%ls:%ls",
838 prefix, path, stream_name_utf16);
840 /* Unnamed stream; its path is just the path to the file itself.
842 stream_path = (wchar_t*)path;
844 ret = win32_begin_extract_unnamed_stream(inode, lte, path,
845 &creationDisposition,
851 DEBUG("Opening \"%ls\"", stream_path);
852 /* DELETE access is needed for SetFileShortNameW(), for some reason. */
853 requestedAccess = GENERIC_READ | GENERIC_WRITE | DELETE |
854 ACCESS_SYSTEM_SECURITY;
856 /* Open the stream to be extracted. Depending on what we have set
857 * creationDisposition to, we may be creating this for the first time,
858 * or we may be opening on existing stream we already created using
859 * CreateDirectoryW() or OpenEncryptedFileRawW(). */
860 h = CreateFileW(stream_path,
865 win32_get_create_flags_and_attributes(inode->i_attributes),
867 if (h == INVALID_HANDLE_VALUE) {
868 err = GetLastError();
869 if (err == ERROR_ACCESS_DENIED &&
870 path_is_root_of_drive(stream_path))
875 if ((err == ERROR_PRIVILEGE_NOT_HELD ||
876 err == ERROR_ACCESS_DENIED) &&
877 (requestedAccess & ACCESS_SYSTEM_SECURITY))
879 /* Try opening the file again without privilege to
881 requestedAccess &= ~ACCESS_SYSTEM_SECURITY;
884 if (err == ERROR_SHARING_VIOLATION) {
885 if (remaining_sharing_violations) {
886 --remaining_sharing_violations;
887 /* This can happen when restoring encrypted directories
888 * for some reason. Probably a bug in EncryptFile(). */
889 WARNING("Couldn't open \"%ls\" due to sharing violation; "
890 "re-trying after 100ms", stream_path);
894 ERROR("Too many sharing violations; giving up...");
897 if (creationDisposition == OPEN_EXISTING)
898 ERROR("Failed to open \"%ls\"", stream_path);
900 ERROR("Failed to create \"%ls\"", stream_path);
903 ret = WIMLIB_ERR_OPEN;
907 /* Check the attributes of the file we just opened, and remove
908 * encryption or compression if either was set by default but is not
909 * supposed to be set based on the WIM inode attributes. */
910 if (!GetFileInformationByHandle(h, &file_info)) {
911 err = GetLastError();
912 ERROR("Failed to get attributes of \"%ls\"", stream_path);
914 ret = WIMLIB_ERR_STAT;
915 goto fail_close_handle;
918 /* Remove encryption? */
919 if (file_info.dwFileAttributes & FILE_ATTRIBUTE_ENCRYPTED &&
920 !(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED))
922 /* File defaulted to encrypted due to being in an encrypted
923 * directory, but is not actually supposed to be encrypted.
925 * This is a workaround, because I'm not aware of any way to
926 * directly (e.g. with CreateFileW()) create an unencrypted file
927 * in a directory with FILE_ATTRIBUTE_ENCRYPTED set. */
928 ret = win32_decrypt_file(h, stream_path);
930 goto fail; /* win32_decrypt_file() closed the handle. */
931 creationDisposition = OPEN_EXISTING;
935 /* Remove compression? */
936 if (file_info.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED &&
937 !(inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED))
939 /* Similar to the encrypted case, above, if the file defaulted
940 * to compressed due to being in an compressed directory, but is
941 * not actually supposed to be compressed, explicitly set the
942 * compression format to COMPRESSION_FORMAT_NONE. */
943 ret = win32_set_compression_state(h, COMPRESSION_FORMAT_NONE,
946 goto fail_close_handle;
949 /* Set compression and/or sparse attributes if needed */
950 ret = win32_set_special_stream_attributes(h, inode, lte, path,
954 goto fail_close_handle;
956 /* At this point we have at least created the needed stream with the
957 * appropriate attributes. We have yet to set the appropriate security
958 * descriptor and actually extract the stream data (other than for
959 * extracted files, which were already extracted).
960 * win32_finish_extract_stream() handles these additional steps. */
961 ret = win32_finish_extract_stream(h, dentry, lte, stream_path,
962 stream_name_utf16, args);
964 goto fail_close_handle;
966 /* Done extracting the stream. Close the handle and return. */
967 DEBUG("Closing \"%ls\"", stream_path);
968 if (!CloseHandle(h)) {
969 err = GetLastError();
970 ERROR("Failed to close \"%ls\"", stream_path);
972 ret = WIMLIB_ERR_WRITE;
980 ERROR("Error extracting \"%ls\"", stream_path);
986 * Creates a file, directory, or reparse point and extracts all streams to it
987 * (unnamed data stream and/or reparse point stream, plus any alternate data
988 * streams). Handles sparse, compressed, and/or encrypted files.
990 * @dentry: WIM dentry for this file or directory.
991 * @path: UTF-16LE external path to extract the inode to.
992 * @args: Additional extraction context.
994 * Returns 0 on success; nonzero on failure.
997 win32_extract_streams(const struct wim_dentry *dentry,
998 const wchar_t *path, struct apply_args *args)
1000 struct wim_lookup_table_entry *unnamed_lte;
1002 const struct wim_inode *inode = dentry->d_inode;
1004 /* First extract the unnamed stream. */
1006 unnamed_lte = inode_unnamed_lte_resolved(inode);
1007 ret = win32_extract_stream(dentry, path, NULL, unnamed_lte, args);
1011 /* Extract any named streams, if supported by the volume. */
1013 if (!(args->vol_flags & FILE_NAMED_STREAMS))
1015 for (u16 i = 0; i < inode->i_num_ads; i++) {
1016 const struct wim_ads_entry *ads_entry = &inode->i_ads_entries[i];
1018 /* Skip the unnamed stream if it's in the ADS entries (we
1019 * already extracted it...) */
1020 if (ads_entry->stream_name_nbytes == 0)
1023 /* Skip special UNIX data entries (see documentation for
1024 * WIMLIB_ADD_FLAG_UNIX_DATA) */
1025 if (ads_entry->stream_name_nbytes == WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES
1026 && !memcmp(ads_entry->stream_name,
1027 WIMLIB_UNIX_DATA_TAG_UTF16LE,
1028 WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES))
1031 /* Extract the named stream */
1032 ret = win32_extract_stream(dentry,
1034 ads_entry->stream_name,
1045 dentry_clear_inode_visited(struct wim_dentry *dentry, void *_ignore)
1047 dentry->d_inode->i_visited = 0;
1052 dentry_get_features(struct wim_dentry *dentry, void *_features_p)
1055 DWORD *features_p = _features_p;
1056 struct wim_inode *inode = dentry->d_inode;
1058 if (inode->i_visited) {
1059 features |= FILE_SUPPORTS_HARD_LINKS;
1061 inode->i_visited = 1;
1062 if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE)
1063 features |= FILE_SUPPORTS_SPARSE_FILES;
1064 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)
1065 features |= FILE_SUPPORTS_REPARSE_POINTS;
1066 for (unsigned i = 0; i < inode->i_num_ads; i++)
1067 if (inode->i_ads_entries[i].stream_name_nbytes)
1068 features |= FILE_NAMED_STREAMS;
1069 if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED)
1070 features |= FILE_SUPPORTS_ENCRYPTION;
1071 if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED)
1072 features |= FILE_FILE_COMPRESSION;
1073 if (inode->i_security_id != -1)
1074 features |= FILE_PERSISTENT_ACLS;
1076 *features_p |= features;
1080 /* If not done already, load the supported feature flags for the volume onto
1081 * which the image is being extracted, and warn the user about any missing
1082 * features that could be important. */
1084 win32_check_vol_flags(const wchar_t *output_path,
1085 struct wim_dentry *root, struct apply_args *args)
1087 DWORD dentry_features = 0;
1088 DWORD missing_features;
1090 if (args->have_vol_flags)
1093 for_dentry_in_tree(root, dentry_clear_inode_visited, NULL);
1094 for_dentry_in_tree(root, dentry_get_features, &dentry_features);
1096 win32_get_vol_flags(output_path, &args->vol_flags);
1097 args->have_vol_flags = true;
1099 missing_features = dentry_features & ~args->vol_flags;
1101 /* Warn the user about data that may not be extracted. */
1102 if (missing_features & FILE_SUPPORTS_SPARSE_FILES)
1103 WARNING("Volume does not support sparse files!\n"
1104 " Sparse files will be extracted as non-sparse.");
1105 if (missing_features & FILE_SUPPORTS_REPARSE_POINTS)
1106 WARNING("Volume does not support reparse points!\n"
1107 " Reparse point data will not be extracted.");
1108 if (missing_features & FILE_NAMED_STREAMS) {
1109 WARNING("Volume does not support named data streams!\n"
1110 " Named data streams will not be extracted.");
1112 if (missing_features & FILE_SUPPORTS_ENCRYPTION) {
1113 WARNING("Volume does not support encryption!\n"
1114 " Encrypted files will be extracted as raw data.");
1116 if (missing_features & FILE_FILE_COMPRESSION) {
1117 WARNING("Volume does not support transparent compression!\n"
1118 " Compressed files will be extracted as non-compressed.");
1120 if (missing_features & FILE_PERSISTENT_ACLS) {
1121 if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
1122 ERROR("Strict ACLs requested, but the volume does not "
1124 return WIMLIB_ERR_VOLUME_LACKS_FEATURES;
1126 WARNING("Volume does not support persistent ACLS!\n"
1127 " File permissions will not be extracted.");
1130 if (running_on_windows_7_or_later() &&
1131 (missing_features & FILE_SUPPORTS_HARD_LINKS))
1133 WARNING("Volume does not support hard links!\n"
1134 " Hard links will be extracted as duplicate files.");
1140 * Try extracting a hard link.
1142 * @output_path: Path to link to be extracted.
1144 * @inode: WIM inode that the link is to; inode->i_extracted_file
1145 * the path to a name of the file that has already been
1146 * extracted (we use this to create the hard link).
1148 * @args: Additional apply context, used here to keep track of
1149 * the number of times creating a hard link failed due to
1150 * ERROR_INVALID_FUNCTION. This error should indicate that hard
1151 * links are not supported by the volume, and we would like to
1152 * warn the user a few times, but not too many times.
1154 * Returns 0 if the hard link was successfully extracted. Returns
1155 * WIMLIB_ERR_LINK (> 0) if an error occurred, other than hard links possibly
1156 * being unsupported by the volume. Returns a negative value if creating the
1157 * hard link failed due to ERROR_INVALID_FUNCTION.
1160 win32_try_hard_link(const wchar_t *output_path, const struct wim_inode *inode,
1161 struct apply_args *args)
1165 /* There is a volume flag for this (FILE_SUPPORTS_HARD_LINKS),
1166 * but it's only available on Windows 7 and later.
1168 * Otherwise, CreateHardLinkW() will apparently return
1169 * ERROR_INVALID_FUNCTION if the volume does not support hard links. */
1171 DEBUG("Creating hard link \"%ls => %ls\"",
1172 output_path, inode->i_extracted_file);
1174 if (running_on_windows_7_or_later() &&
1175 !(args->vol_flags & FILE_SUPPORTS_HARD_LINKS))
1176 goto hard_links_unsupported;
1178 if (CreateHardLinkW(output_path, inode->i_extracted_file, NULL))
1181 err = GetLastError();
1182 if (err != ERROR_INVALID_FUNCTION) {
1183 ERROR("Can't create hard link \"%ls => %ls\"",
1184 output_path, inode->i_extracted_file);
1186 return WIMLIB_ERR_LINK;
1188 hard_links_unsupported:
1189 args->num_hard_links_failed++;
1190 if (args->num_hard_links_failed <= MAX_CREATE_HARD_LINK_WARNINGS) {
1191 if (running_on_windows_7_or_later())
1193 WARNING("Extracting duplicate copy of \"%ls\" "
1194 "rather than hard link", output_path);
1196 WARNING("Can't create hard link \"%ls\" => \"%ls\":\n"
1197 " Volume does not support hard links!\n"
1198 " Falling back to extracting a copy of the file.",
1199 output_path, inode->i_extracted_file);
1202 if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS)
1203 WARNING("Suppressing further hard linking warnings...");
1207 /* Extract a file, directory, reparse point, or hard link to an
1208 * already-extracted file using the Win32 API */
1210 win32_do_apply_dentry(const wchar_t *output_path,
1211 size_t output_path_num_chars,
1212 struct wim_dentry *dentry,
1213 struct apply_args *args)
1216 struct wim_inode *inode = dentry->d_inode;
1218 ret = win32_check_vol_flags(output_path, dentry, args);
1221 if (inode->i_nlink > 1 && inode->i_extracted_file != NULL) {
1222 /* Linked file, with another name already extracted. Create a
1224 ret = win32_try_hard_link(output_path, inode, args);
1227 /* Negative return value from win32_try_hard_link() indicates
1228 * that hard links are probably not supported by the volume.
1229 * Fall back to extracting a copy of the file. */
1232 /* If this is a reparse point and the volume does not support reparse
1233 * points, just skip it completely. */
1234 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
1235 !(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
1237 WARNING("Not extracting reparse point \"%ls\"", output_path);
1239 /* Create the file, directory, or reparse point, and extract the
1241 ret = win32_extract_streams(dentry, output_path, args);
1245 if (inode->i_extracted_file == NULL) {
1246 const struct wim_lookup_table_entry *lte;
1248 /* Tally bytes extracted, including all alternate data streams,
1249 * unless we extracted a hard link (or, at least extracted a
1250 * name that was supposed to be a hard link) */
1251 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1252 lte = inode_stream_lte_resolved(inode, i);
1254 args->progress.extract.completed_bytes +=
1255 wim_resource_size(lte);
1257 if (inode->i_nlink > 1) {
1258 /* Save extracted path for a later call to
1259 * CreateHardLinkW() if this inode has multiple links.
1261 inode->i_extracted_file = WSTRDUP(output_path);
1262 if (!inode->i_extracted_file)
1263 return WIMLIB_ERR_NOMEM;
1269 /* Set timestamps on an extracted file using the Win32 API */
1271 win32_do_apply_dentry_timestamps(const wchar_t *path,
1272 size_t path_num_chars,
1273 struct wim_dentry *dentry,
1274 struct apply_args *args)
1278 const struct wim_inode *inode = dentry->d_inode;
1280 if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
1281 !(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
1283 /* Skip reparse points not extracted */
1287 /* Windows doesn't let you change the timestamps of the root directory
1288 * (at least on FAT, which is dumb but expected since FAT doesn't store
1289 * any metadata about the root directory...) */
1290 if (path_is_root_of_drive(path))
1293 DEBUG("Opening \"%ls\" to set timestamps", path);
1294 h = win32_open_existing_file(path, FILE_WRITE_ATTRIBUTES);
1295 if (h == INVALID_HANDLE_VALUE) {
1296 err = GetLastError();
1300 FILETIME creationTime = {.dwLowDateTime = inode->i_creation_time & 0xffffffff,
1301 .dwHighDateTime = inode->i_creation_time >> 32};
1302 FILETIME lastAccessTime = {.dwLowDateTime = inode->i_last_access_time & 0xffffffff,
1303 .dwHighDateTime = inode->i_last_access_time >> 32};
1304 FILETIME lastWriteTime = {.dwLowDateTime = inode->i_last_write_time & 0xffffffff,
1305 .dwHighDateTime = inode->i_last_write_time >> 32};
1307 DEBUG("Calling SetFileTime() on \"%ls\"", path);
1308 if (!SetFileTime(h, &creationTime, &lastAccessTime, &lastWriteTime)) {
1309 err = GetLastError();
1313 DEBUG("Closing \"%ls\"", path);
1314 if (!CloseHandle(h)) {
1315 err = GetLastError();
1320 /* Only warn if setting timestamps failed; still return 0. */
1321 WARNING("Can't set timestamps on \"%ls\"", path);
1327 #endif /* __WIN32__ */