/*
* Copyright (C) 2013, 2014 Eric Biggers
*
- * This file is part of wimlib, a library for working with WIM files.
+ * This file is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your option) any
+ * later version.
*
- * wimlib is free software; you can redistribute it and/or modify it under the
- * terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 3 of the License, or (at your option)
- * any later version.
- *
- * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
- * A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * This file is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*
- * You should have received a copy of the GNU General Public License
- * along with wimlib; if not, see http://www.gnu.org/licenses/.
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this file; if not, see http://www.gnu.org/licenses/.
*/
#ifdef __WIN32__
#include "wimlib/reparse.h"
#include "wimlib/textfile.h"
#include "wimlib/xml.h"
+#include "wimlib/wildcard.h"
#include "wimlib/wimboot.h"
struct win32_apply_ctx {
void *mem_prepopulate_pats;
u8 wim_lookup_table_hash[SHA1_HASH_SIZE];
bool wof_running;
+ bool tried_to_load_prepopulate_list;
} wimboot;
/* Open handle to the target directory */
}
}
+static const wchar_t *
+current_path(struct win32_apply_ctx *ctx);
+
+static void
+build_extraction_path(const struct wim_dentry *dentry,
+ struct win32_apply_ctx *ctx);
+
static int
win32_get_supported_features(const wchar_t *target,
struct wim_features *supported_features)
void *mem;
struct text_file_section sec;
+ ctx->wimboot.tried_to_load_prepopulate_list = true;
+
dentry = get_dentry(ctx->common.wim, path, WIMLIB_CASE_INSENSITIVE);
if (!dentry ||
(dentry->d_inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
return 0;
}
-/* Returns %true if the path to @dentry matches a pattern in [PrepopulateList]
- * of WimBootCompress.ini. Otherwise returns %false.
- *
- * @dentry must have had its full path calculated. */
+/* Returns %true if the specified absolute path to a file in the WIM image
+ * matches a pattern in [PrepopulateList] of WimBootCompress.ini. Otherwise
+ * returns %false. */
static bool
-in_prepopulate_list(struct wim_dentry *dentry,
+in_prepopulate_list(const wchar_t *path, size_t path_nchars,
const struct win32_apply_ctx *ctx)
{
const struct string_set *pats = ctx->wimboot.prepopulate_pats;
if (!pats || !pats->num_strings)
return false;
- return match_pattern_list(dentry->_full_path,
- wcslen(dentry->_full_path), pats);
+ return match_pattern_list(path, path_nchars, pats);
+}
+
+/* Returns %true if the specified absolute path to a file in the WIM image can
+ * be subject to external backing when extracted. Otherwise returns %false. */
+static bool
+can_externally_back_path(const wchar_t *path, size_t path_nchars,
+ const struct win32_apply_ctx *ctx)
+{
+ if (in_prepopulate_list(path, path_nchars, ctx))
+ return false;
+
+ /* Since we attempt to modify the SYSTEM registry after it's extracted
+ * (see end_wimboot_extraction()), it can't be extracted as externally
+ * backed. This extends to associated files such as SYSTEM.LOG that
+ * also must be writable in order to write to the registry. Normally,
+ * SYSTEM is in [PrepopulateList], and the SYSTEM.* files match patterns
+ * in [ExclusionList] and therefore are not captured in the WIM at all.
+ * However, a WIM that wasn't specifically captured in "WIMBoot mode"
+ * may contain SYSTEM.* files. So to make things "just work", hard-code
+ * the pattern. */
+ if (match_path(path, path_nchars, L"\\Windows\\System32\\config\\SYSTEM*",
+ OS_PREFERRED_PATH_SEPARATOR, false))
+ return false;
+
+ return true;
+}
+
+#define WIM_BACKING_NOT_ENABLED -1
+#define WIM_BACKING_NOT_POSSIBLE -2
+#define WIM_BACKING_EXCLUDED -3
+
+static int
+will_externally_back_inode(struct wim_inode *inode, struct win32_apply_ctx *ctx,
+ const struct wim_dentry **excluded_dentry_ret)
+{
+ struct list_head *next;
+ struct wim_dentry *dentry;
+ struct wim_lookup_table_entry *stream;
+ int ret;
+
+ if (inode->i_can_externally_back)
+ return 0;
+
+ /* This may do redundant checks because the cached value
+ * i_can_externally_back is 2-state (as opposed to 3-state:
+ * unknown/no/yes). But most files can be externally backed, so this
+ * way is fine. */
+
+ if (inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
+ FILE_ATTRIBUTE_REPARSE_POINT |
+ FILE_ATTRIBUTE_ENCRYPTED))
+ return WIM_BACKING_NOT_POSSIBLE;
+
+ stream = inode_unnamed_lte_resolved(inode);
+
+ if (!stream ||
+ stream->resource_location != RESOURCE_IN_WIM ||
+ stream->rspec->wim != ctx->common.wim ||
+ stream->size != stream->rspec->uncompressed_size)
+ return WIM_BACKING_NOT_POSSIBLE;
+
+ /*
+ * We need to check the patterns in [PrepopulateList] against every name
+ * of the inode, in case any of them match.
+ */
+ next = inode->i_extraction_aliases.next;
+ do {
+ dentry = list_entry(next, struct wim_dentry,
+ d_extraction_alias_node);
+
+ ret = calculate_dentry_full_path(dentry);
+ if (ret)
+ return ret;
+
+ if (!can_externally_back_path(dentry->_full_path,
+ wcslen(dentry->_full_path), ctx))
+ {
+ if (excluded_dentry_ret)
+ *excluded_dentry_ret = dentry;
+ return WIM_BACKING_EXCLUDED;
+ }
+ next = next->next;
+ } while (next != &inode->i_extraction_aliases);
+
+ inode->i_can_externally_back = 1;
+ return 0;
+}
+
+/*
+ * Determines if the unnamed data stream of a file will be created as an
+ * external backing, as opposed to a standard extraction.
+ */
+static int
+win32_will_externally_back(struct wim_dentry *dentry, struct apply_ctx *_ctx)
+{
+ struct win32_apply_ctx *ctx = (struct win32_apply_ctx *)_ctx;
+
+ if (!(ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT))
+ return WIM_BACKING_NOT_ENABLED;
+
+ if (!ctx->wimboot.tried_to_load_prepopulate_list)
+ if (load_prepopulate_pats(ctx) == WIMLIB_ERR_NOMEM)
+ return WIMLIB_ERR_NOMEM;
+
+ return will_externally_back_inode(dentry->d_inode, ctx, NULL);
+}
+
+static int
+set_external_backing(HANDLE h, struct wim_inode *inode, struct win32_apply_ctx *ctx)
+{
+ int ret;
+ const struct wim_dentry *excluded_dentry;
+
+ ret = will_externally_back_inode(inode, ctx, &excluded_dentry);
+ if (ret > 0) /* Error. */
+ return ret;
+
+ if (ret < 0 && ret != WIM_BACKING_EXCLUDED)
+ return 0; /* Not externally backing, other than due to exclusion. */
+
+ if (unlikely(ret == WIM_BACKING_EXCLUDED)) {
+ /* Not externally backing due to exclusion. */
+ union wimlib_progress_info info;
+
+ build_extraction_path(excluded_dentry, ctx);
+
+ info.wimboot_exclude.path_in_wim = excluded_dentry->_full_path;
+ info.wimboot_exclude.extraction_path = current_path(ctx);
+
+ return call_progress(ctx->common.progfunc,
+ WIMLIB_PROGRESS_MSG_WIMBOOT_EXCLUDE,
+ &info, ctx->common.progctx);
+ } else {
+ /* Externally backing. */
+ if (unlikely(!wimboot_set_pointer(h,
+ inode_unnamed_lte_resolved(inode),
+ ctx->wimboot.data_source_id,
+ ctx->wimboot.wim_lookup_table_hash,
+ ctx->wimboot.wof_running)))
+ {
+ const DWORD err = GetLastError();
+
+ build_extraction_path(inode_first_extraction_dentry(inode), ctx);
+ set_errno_from_win32_error(err);
+ ERROR_WITH_ERRNO("\"%ls\": Couldn't set WIMBoot "
+ "pointer data (err=%"PRIu32")",
+ current_path(ctx), (u32)err);
+ return WIMLIB_ERR_WIMBOOT;
+ }
+ return 0;
+ }
}
/* Calculates the SHA-1 message digest of the WIM's lookup table. */
int ret;
WIMStruct *wim = ctx->common.wim;
- ret = load_prepopulate_pats(ctx);
- if (ret == WIMLIB_ERR_NOMEM)
- return ret;
+ if (!ctx->wimboot.tried_to_load_prepopulate_list)
+ if (load_prepopulate_pats(ctx) == WIMLIB_ERR_NOMEM)
+ return WIMLIB_ERR_NOMEM;
if (!wim_info_get_wimboot(wim->wim_info, wim->current_image))
WARNING("Image is not marked as WIMBoot compatible!");
/* When creating an inode that will have a short (DOS) name, we create it using
* the long name associated with the short name. This ensures that the short
* name gets associated with the correct long name. */
-static const struct wim_dentry *
+static struct wim_dentry *
first_extraction_alias(const struct wim_inode *inode)
{
- const struct list_head *next = inode->i_extraction_aliases.next;
- const struct wim_dentry *dentry;
+ struct list_head *next = inode->i_extraction_aliases.next;
+ struct wim_dentry *dentry;
do {
dentry = list_entry(next, struct wim_dentry,
/* Create a nondirectory file, including all links. */
static int
-create_nondirectory(const struct wim_inode *inode, struct win32_apply_ctx *ctx)
+create_nondirectory(struct wim_inode *inode, struct win32_apply_ctx *ctx)
{
- const struct wim_dentry *first_dentry;
+ struct wim_dentry *first_dentry;
HANDLE h;
int ret;
if (!ret)
ret = create_links(h, first_dentry, ctx);
+ /* "WIMBoot" extraction: set external backing by the WIM file if needed. */
+ if (!ret && unlikely(ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT))
+ ret = set_external_backing(h, inode, ctx);
+
(*func_NtClose)(h);
return ret;
}
static int
create_nondirectories(struct list_head *dentry_list, struct win32_apply_ctx *ctx)
{
- const struct wim_dentry *dentry;
- const struct wim_inode *inode;
+ struct wim_dentry *dentry;
+ struct wim_inode *inode;
int ret;
list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
return prepare_data_buffer(ctx, stream->size);
}
- /* Extracting unnamed data stream in WIMBoot mode? */
- if (unlikely(ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT)
- && (stream_name_nchars == 0)
- && (stream->resource_location == RESOURCE_IN_WIM)
- && (stream->rspec->wim == ctx->common.wim)
- && (stream->size == stream->rspec->uncompressed_size))
- {
- int ret = calculate_dentry_full_path(dentry);
- if (ret)
- return ret;
- if (in_prepopulate_list(dentry, ctx)) {
- union wimlib_progress_info info;
-
- info.wimboot_exclude.path_in_wim = dentry->_full_path;
- info.wimboot_exclude.extraction_path = current_path(ctx);
-
- ret = call_progress(ctx->common.progfunc,
- WIMLIB_PROGRESS_MSG_WIMBOOT_EXCLUDE,
- &info, ctx->common.progctx);
- FREE(dentry->_full_path);
- dentry->_full_path = NULL;
- if (ret)
- return ret;
- /* Go on and open the file for normal extraction. */
- } else {
- FREE(dentry->_full_path);
- dentry->_full_path = NULL;
- return wimboot_set_pointer(&ctx->attr,
- current_path(ctx),
- stream,
- ctx->wimboot.data_source_id,
- ctx->wimboot.wim_lookup_table_hash,
- ctx->wimboot.wof_running);
- }
- }
-
if (ctx->num_open_handles == MAX_OPEN_STREAMS) {
/* XXX: Fix this. But because of the checks in
* extract_stream_list(), this can now only happen on a
/* Set the security descriptor @desc, of @desc_size bytes, on the file with open
* handle @h. */
static NTSTATUS
-set_security_descriptor(HANDLE h, const void *desc,
+set_security_descriptor(HANDLE h, const void *_desc,
size_t desc_size, struct win32_apply_ctx *ctx)
{
SECURITY_INFORMATION info;
NTSTATUS status;
+ SECURITY_DESCRIPTOR_RELATIVE *desc;
+
+ /*
+ * Ideally, we would just pass in the security descriptor buffer as-is.
+ * But it turns out that Windows can mess up the security descriptor
+ * even when using the low-level NtSetSecurityObject() function:
+ *
+ * - Windows will clear SE_DACL_AUTO_INHERITED if it is set in the
+ * passed buffer. To actually get Windows to set
+ * SE_DACL_AUTO_INHERITED, the application must set the non-persistent
+ * flag SE_DACL_AUTO_INHERIT_REQ. As usual, Microsoft didn't bother
+ * to properly document either of these flags. It's unclear how
+ * important SE_DACL_AUTO_INHERITED actually is, but to be safe we use
+ * the SE_DACL_AUTO_INHERIT_REQ workaround to set it if needed.
+ *
+ * - The above also applies to the equivalent SACL flags,
+ * SE_SACL_AUTO_INHERITED and SE_SACL_AUTO_INHERIT_REQ.
+ *
+ * - If the application says that it's setting
+ * DACL_SECURITY_INFORMATION, then Windows sets SE_DACL_PRESENT in the
+ * resulting security descriptor, even if the security descriptor the
+ * application provided did not have a DACL. This seems to be
+ * unavoidable, since omitting DACL_SECURITY_INFORMATION would cause a
+ * default DACL to remain. Fortunately, this behavior seems harmless,
+ * since the resulting DACL will still be "null" --- but it will be
+ * "the other representation of null".
+ *
+ * - The above also applies to SACL_SECURITY_INFORMATION and
+ * SE_SACL_PRESENT. Again, it's seemingly unavoidable but "harmless"
+ * that Windows changes the representation of a "null SACL".
+ */
+ if (likely(desc_size <= STACK_MAX)) {
+ desc = alloca(desc_size);
+ } else {
+ desc = MALLOC(desc_size);
+ if (!desc)
+ return STATUS_NO_MEMORY;
+ }
+
+ memcpy(desc, _desc, desc_size);
+
+ if (likely(desc_size >= 4)) {
+
+ if (desc->Control & SE_DACL_AUTO_INHERITED)
+ desc->Control |= SE_DACL_AUTO_INHERIT_REQ;
+
+ if (desc->Control & SE_SACL_AUTO_INHERITED)
+ desc->Control |= SE_SACL_AUTO_INHERIT_REQ;
+ }
+
+ /*
+ * More API insanity. We want to set the entire security descriptor
+ * as-is. But all available APIs require specifying the specific parts
+ * of the security descriptor being set. Especially annoying is that
+ * mandatory integrity labels are part of the SACL, but they aren't set
+ * with SACL_SECURITY_INFORMATION. Instead, applications must also
+ * specify LABEL_SECURITY_INFORMATION (Windows Vista, Windows 7) or
+ * BACKUP_SECURITY_INFORMATION (Windows 8). But at least older versions
+ * of Windows don't error out if you provide these newer flags...
+ *
+ * Also, if the process isn't running as Administrator, then it probably
+ * doesn't have SE_RESTORE_PRIVILEGE. In this case, it will always get
+ * the STATUS_PRIVILEGE_NOT_HELD error by trying to set the SACL, even
+ * if the security descriptor it provided did not have a SACL. By
+ * default, in this case we try to recover and set as much of the
+ * security descriptor as possible --- potentially excluding the DACL, and
+ * even the owner, as well as the SACL.
+ */
- /* We really just want to set entire the security descriptor as-is, but
- * all available APIs require specifying the specific parts of the
- * descriptor being set. Start out by requesting all parts be set. If
- * permissions problems are encountered, fall back to omitting some
- * parts (first the SACL, then the DACL, then the owner), unless the
- * WIMLIB_EXTRACT_FLAG_STRICT_ACLS flag has been enabled. */
info = OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION |
- DACL_SECURITY_INFORMATION | SACL_SECURITY_INFORMATION;
-
- /* Prefer NtSetSecurityObject() to SetFileSecurity(). SetFileSecurity()
- * itself necessarily uses NtSetSecurityObject() as the latter is the
- * underlying system call for setting security information, but
- * SetFileSecurity() opens the handle with NtCreateFile() without
- * FILE_OPEN_FILE_BACKUP_INTENT. Hence, access checks are done and due
- * to the Windows security model, even a process running as the
- * Administrator can have access denied. (Of course, this not mentioned
- * in the MS "documentation".) */
+ DACL_SECURITY_INFORMATION | SACL_SECURITY_INFORMATION |
+ LABEL_SECURITY_INFORMATION | BACKUP_SECURITY_INFORMATION;
+
+
+ /*
+ * It's also worth noting that SetFileSecurity() is unusable because it
+ * doesn't request "backup semantics" when it opens the file internally.
+ * NtSetSecurityObject() seems to be the best function to use in backup
+ * applications. (SetSecurityInfo() should also work, but it's harder
+ * to use and must call NtSetSecurityObject() internally anyway.
+ * BackupWrite() is theoretically usable as well, but it's inflexible
+ * and poorly documented.)
+ */
+
retry:
- status = (*func_NtSetSecurityObject)(h, info, (PSECURITY_DESCRIPTOR)desc);
+ status = (*func_NtSetSecurityObject)(h, info, desc);
if (NT_SUCCESS(status))
- return status;
+ goto out_maybe_free_desc;
+
/* Failed to set the requested parts of the security descriptor. If the
* error was permissions-related, try to set fewer parts of the security
* descriptor, unless WIMLIB_EXTRACT_FLAG_STRICT_ACLS is enabled. */
!(ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
{
if (info & SACL_SECURITY_INFORMATION) {
- info &= ~SACL_SECURITY_INFORMATION;
+ info &= ~(SACL_SECURITY_INFORMATION |
+ LABEL_SECURITY_INFORMATION |
+ BACKUP_SECURITY_INFORMATION);
ctx->partial_security_descriptors++;
goto retry;
}
if (!(info & SACL_SECURITY_INFORMATION))
ctx->partial_security_descriptors--;
ctx->no_security_descriptors++;
+
+out_maybe_free_desc:
+ if (unlikely(desc_size > STACK_MAX))
+ FREE(desc);
return status;
}
.name = "Windows",
.get_supported_features = win32_get_supported_features,
.extract = win32_extract,
+ .will_externally_back = win32_will_externally_back,
.context_size = sizeof(struct win32_apply_ctx),
};
git://wimlib.net / wimlib / blobdiff