]> wimlib.net Git - wimlib/blobdiff - src/win32_apply.c
system compression: force XPRESS4K on files accessed by Windows bootloader
[wimlib] / src / win32_apply.c
index 7593f20e23a65cfad914a255689f033b7532366e..5bc1e51f9c12b3ba68a8c37b5ac9629a2d986962 100644 (file)
 #include "wimlib/error.h"
 #include "wimlib/metadata.h"
 #include "wimlib/paths.h"
+#include "wimlib/pattern.h"
 #include "wimlib/reparse.h"
 #include "wimlib/textfile.h"
 #include "wimlib/xml.h"
-#include "wimlib/wildcard.h"
 #include "wimlib/wimboot.h"
+#include "wimlib/wof.h"
 
 struct win32_apply_ctx {
 
@@ -59,17 +60,18 @@ struct win32_apply_ctx {
                        u8 blob_table_hash[SHA1_HASH_SIZE];
                } *wims;
                size_t num_wims;
-               struct string_set *prepopulate_pats;
-               void *mem_prepopulate_pats;
                bool wof_running;
-               bool tried_to_load_prepopulate_list;
-
                bool have_wrong_version_wims;
                bool have_uncompressed_wims;
                bool have_unsupported_compressed_resources;
                bool have_huge_resources;
        } wimboot;
 
+       /* External backing information  */
+       struct string_set *prepopulate_pats;
+       void *mem_prepopulate_pats;
+       bool tried_to_load_prepopulate_list;
+
        /* Open handle to the target directory  */
        HANDLE h_target;
 
@@ -122,12 +124,12 @@ struct win32_apply_ctx {
         * beginning of the array)  */
        unsigned num_open_handles;
 
-       /* List of dentries, joined by @tmp_list, that need to have reparse data
-        * extracted as soon as the whole blob has been read into @data_buffer.
-        * */
+       /* List of dentries, joined by @d_tmp_list, that need to have reparse
+        * data extracted as soon as the whole blob has been read into
+        * @data_buffer.  */
        struct list_head reparse_dentries;
 
-       /* List of dentries, joined by @tmp_list, that need to have raw
+       /* List of dentries, joined by @d_tmp_list, that need to have raw
         * encrypted data extracted as soon as the whole blob has been read into
         * @data_buffer.  */
        struct list_head encrypted_dentries;
@@ -146,6 +148,14 @@ struct win32_apply_ctx {
        /* Number of files for which we couldn't remove the short name.  */
        unsigned long num_remove_short_name_failures;
 
+       /* Number of files on which we couldn't set System Compression.  */
+       unsigned long num_system_compression_failures;
+
+       /* The number of files on which we used XPRESS4K System Compression
+        * rather than a stronger variant, to be compatible with the Windows
+        * bootloader.  */
+       unsigned long num_xpress4k_forced_files;
+
        /* Have we tried to enable short name support on the target volume yet?
         */
        bool tried_to_enable_short_names;
@@ -282,8 +292,22 @@ win32_get_supported_features(const wchar_t *target,
        return 0;
 }
 
-/* Load the patterns from [PrepopulateList] of WimBootCompress.ini in the WIM
- * image being extracted.  */
+#define COMPACT_FLAGS  (WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS4K |         \
+                        WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS8K |         \
+                        WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS16K |        \
+                        WIMLIB_EXTRACT_FLAG_COMPACT_LZX)
+
+
+
+/*
+ * If not done already, load the patterns from the [PrepopulateList] section of
+ * WimBootCompress.ini in the WIM image being extracted.
+ *
+ * Note: WimBootCompress.ini applies to both types of "external backing":
+ *
+ *     - WIM backing ("WIMBoot" - Windows 8.1 and later)
+ *     - File backing ("System Compression" - Windows 10 and later)
+ */
 static int
 load_prepopulate_pats(struct win32_apply_ctx *ctx)
 {
@@ -296,7 +320,10 @@ load_prepopulate_pats(struct win32_apply_ctx *ctx)
        void *mem;
        struct text_file_section sec;
 
-       ctx->wimboot.tried_to_load_prepopulate_list = true;
+       if (ctx->tried_to_load_prepopulate_list)
+               return 0;
+
+       ctx->tried_to_load_prepopulate_list = true;
 
        dentry = get_dentry(ctx->common.wim, path, WIMLIB_CASE_INSENSITIVE);
        if (!dentry ||
@@ -330,39 +357,25 @@ load_prepopulate_pats(struct win32_apply_ctx *ctx)
                                LOAD_TEXT_FILE_REMOVE_QUOTES |
                                        LOAD_TEXT_FILE_NO_WARNINGS,
                                mangle_pat);
-       BUILD_BUG_ON(OS_PREFERRED_PATH_SEPARATOR != WIM_PATH_SEPARATOR);
+       STATIC_ASSERT(OS_PREFERRED_PATH_SEPARATOR == WIM_PATH_SEPARATOR);
        FREE(buf);
        if (ret) {
                FREE(s);
                return ret;
        }
-       ctx->wimboot.prepopulate_pats = s;
-       ctx->wimboot.mem_prepopulate_pats = mem;
+       ctx->prepopulate_pats = s;
+       ctx->mem_prepopulate_pats = mem;
        return 0;
 }
 
-/* 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(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(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)
+can_externally_back_path(const wchar_t *path, const struct win32_apply_ctx *ctx)
 {
-       if (in_prepopulate_list(path, path_nchars, ctx))
+       /* Does the path match a pattern given in the [PrepopulateList] section
+        * of WimBootCompress.ini?  */
+       if (ctx->prepopulate_pats && match_pattern_list(path, ctx->prepopulate_pats))
                return false;
 
        /* Since we attempt to modify the SYSTEM registry after it's extracted
@@ -374,13 +387,14 @@ can_externally_back_path(const wchar_t *path, size_t path_nchars,
         * 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))
+       if (match_path(path, L"\\Windows\\System32\\config\\SYSTEM*", false))
                return false;
 
        return true;
 }
 
+/* Can the specified WIM resource be used as the source of an external backing
+ * for the wof.sys WIM provider?  */
 static bool
 is_resource_valid_for_external_backing(const struct wim_resource_descriptor *rdesc,
                                       struct win32_apply_ctx *ctx)
@@ -450,18 +464,38 @@ is_resource_valid_for_external_backing(const struct wim_resource_descriptor *rde
        return true;
 }
 
-#define WIM_BACKING_NOT_ENABLED                -1
-#define WIM_BACKING_NOT_POSSIBLE       -2
-#define WIM_BACKING_EXCLUDED           -3
+#define EXTERNAL_BACKING_NOT_ENABLED           -1
+#define EXTERNAL_BACKING_NOT_POSSIBLE          -2
+#define EXTERNAL_BACKING_EXCLUDED              -3
 
+/*
+ * Determines whether the specified file will be externally backed.  Returns a
+ * negative status code if no, 0 if yes, or a positive wimlib error code on
+ * error.  If the file is excluded from external backing based on its path, then
+ * *excluded_dentry_ret is set to the dentry for the path that matched the
+ * exclusion rule.
+ *
+ * Note that this logic applies to both types of "external backing":
+ *
+ *     - WIM backing ("WIMBoot" - Windows 8.1 and later)
+ *     - File backing ("System Compression" - Windows 10 and later)
+ *
+ * However, in the case of WIM backing we also need to validate that the WIM
+ * resource that would be the source of the backing is supported by the wof.sys
+ * WIM provider.
+ */
 static int
 will_externally_back_inode(struct wim_inode *inode, struct win32_apply_ctx *ctx,
-                          const struct wim_dentry **excluded_dentry_ret)
+                          const struct wim_dentry **excluded_dentry_ret,
+                          bool wimboot_mode)
 {
        struct wim_dentry *dentry;
        struct blob_descriptor *blob;
        int ret;
 
+       if (load_prepopulate_pats(ctx) == WIMLIB_ERR_NOMEM)
+               return WIMLIB_ERR_NOMEM;
+
        if (inode->i_can_externally_back)
                return 0;
 
@@ -473,13 +507,17 @@ will_externally_back_inode(struct wim_inode *inode, struct win32_apply_ctx *ctx,
        if (inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
                                   FILE_ATTRIBUTE_REPARSE_POINT |
                                   FILE_ATTRIBUTE_ENCRYPTED))
-               return WIM_BACKING_NOT_POSSIBLE;
+               return EXTERNAL_BACKING_NOT_POSSIBLE;
 
        blob = inode_get_blob_for_unnamed_data_stream_resolved(inode);
 
-       if (!blob || blob->blob_location != BLOB_IN_WIM ||
-           !is_resource_valid_for_external_backing(blob->rdesc, ctx))
-               return WIM_BACKING_NOT_POSSIBLE;
+       if (!blob)
+               return EXTERNAL_BACKING_NOT_POSSIBLE;
+
+       if (wimboot_mode &&
+           (blob->blob_location != BLOB_IN_WIM ||
+            !is_resource_valid_for_external_backing(blob->rdesc, ctx)))
+               return EXTERNAL_BACKING_NOT_POSSIBLE;
 
        /*
         * We need to check the patterns in [PrepopulateList] against every name
@@ -492,12 +530,10 @@ will_externally_back_inode(struct wim_inode *inode, struct win32_apply_ctx *ctx,
                if (ret)
                        return ret;
 
-               if (!can_externally_back_path(dentry->_full_path,
-                                             wcslen(dentry->_full_path), ctx))
-               {
+               if (!can_externally_back_path(dentry->d_full_path, ctx)) {
                        if (excluded_dentry_ret)
                                *excluded_dentry_ret = dentry;
-                       return WIM_BACKING_EXCLUDED;
+                       return EXTERNAL_BACKING_EXCLUDED;
                }
        }
 
@@ -506,22 +542,19 @@ will_externally_back_inode(struct wim_inode *inode, struct win32_apply_ctx *ctx,
 }
 
 /*
- * Determines if the unnamed data stream of a file will be created as an
- * external backing, as opposed to a standard extraction.
+ * Determines if the unnamed data stream of a file will be created as a WIM
+ * external backing (a "WIMBoot pointer file"), as opposed to a standard
+ * extraction.
  */
 static int
-win32_will_externally_back(struct wim_dentry *dentry, struct apply_ctx *_ctx)
+win32_will_back_from_wim(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;
+               return EXTERNAL_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);
+       return will_externally_back_inode(dentry->d_inode, ctx, NULL, true);
 }
 
 /* Find the WOF registration information for the specified WIM file.  */
@@ -537,27 +570,27 @@ find_wimboot_wim(WIMStruct *wim_to_find, struct win32_apply_ctx *ctx)
 }
 
 static int
-set_external_backing(HANDLE h, struct wim_inode *inode, struct win32_apply_ctx *ctx)
+set_backed_from_wim(HANDLE h, struct wim_inode *inode, struct win32_apply_ctx *ctx)
 {
        int ret;
        const struct wim_dentry *excluded_dentry;
        const struct blob_descriptor *blob;
        const struct wimboot_wim *wimboot_wim;
 
-       ret = will_externally_back_inode(inode, ctx, &excluded_dentry);
+       ret = will_externally_back_inode(inode, ctx, &excluded_dentry, true);
        if (ret > 0) /* Error.  */
                return ret;
 
-       if (ret < 0 && ret != WIM_BACKING_EXCLUDED)
+       if (ret < 0 && ret != EXTERNAL_BACKING_EXCLUDED)
                return 0; /* Not externally backing, other than due to exclusion.  */
 
-       if (unlikely(ret == WIM_BACKING_EXCLUDED)) {
+       if (unlikely(ret == EXTERNAL_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.path_in_wim = excluded_dentry->d_full_path;
                info.wimboot_exclude.extraction_path = current_path(ctx);
 
                return call_progress(ctx->common.progfunc,
@@ -631,8 +664,7 @@ register_wim_with_wof(WIMStruct *wim, struct win32_apply_ctx *ctx)
        return 0;
 }
 
-/* Prepare for doing a "WIMBoot" extraction by loading patterns from
- * [PrepopulateList] of WimBootCompress.ini and registering each source WIM file
+/* Prepare for doing a "WIMBoot" extraction by registering each source WIM file
  * with WOF on the target volume.  */
 static int
 start_wimboot_extraction(struct list_head *dentry_list, struct win32_apply_ctx *ctx)
@@ -640,10 +672,6 @@ start_wimboot_extraction(struct list_head *dentry_list, struct win32_apply_ctx *
        int ret;
        struct wim_dentry *dentry;
 
-       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(ctx->common.wim->wim_info,
                                  ctx->common.wim->current_image))
                WARNING("The WIM image is not marked as WIMBoot compatible.  This usually\n"
@@ -653,7 +681,7 @@ start_wimboot_extraction(struct list_head *dentry_list, struct win32_apply_ctx *
        list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
                struct blob_descriptor *blob;
 
-               ret = win32_will_externally_back(dentry, &ctx->common);
+               ret = win32_will_back_from_wim(dentry, &ctx->common);
                if (ret > 0) /* Error */
                        return ret;
                if (ret < 0) /* Won't externally back */
@@ -1149,7 +1177,7 @@ remove_conflicting_short_name(const struct wim_dentry *dentry, struct win32_appl
        name = &ctx->pathbuf.Buffer[ctx->pathbuf.Length / sizeof(wchar_t)];
        while (name != ctx->pathbuf.Buffer && *(name - 1) != L'\\')
                name--;
-       end = mempcpy(name, dentry->short_name, dentry->short_name_nbytes);
+       end = mempcpy(name, dentry->d_short_name, dentry->d_short_name_nbytes);
        ctx->pathbuf.Length = ((u8 *)end - (u8 *)ctx->pathbuf.Buffer);
 
        /* Open the conflicting file (by short name).  */
@@ -1226,7 +1254,7 @@ set_short_name(HANDLE h, const struct wim_dentry *dentry,
         */
 
        size_t bufsize = offsetof(FILE_NAME_INFORMATION, FileName) +
-                        max(dentry->short_name_nbytes, sizeof(wchar_t)) +
+                        max(dentry->d_short_name_nbytes, sizeof(wchar_t)) +
                         sizeof(wchar_t);
        u8 buf[bufsize] _aligned_attribute(8);
        FILE_NAME_INFORMATION *info = (FILE_NAME_INFORMATION *)buf;
@@ -1235,8 +1263,8 @@ set_short_name(HANDLE h, const struct wim_dentry *dentry,
 
        memset(buf, 0, bufsize);
 
-       info->FileNameLength = dentry->short_name_nbytes;
-       memcpy(info->FileName, dentry->short_name, dentry->short_name_nbytes);
+       info->FileNameLength = dentry->d_short_name_nbytes;
+       memcpy(info->FileName, dentry->d_short_name, dentry->d_short_name_nbytes);
 
 retry:
        status = (*func_NtSetInformationFile)(h, &ctx->iosb, info, bufsize,
@@ -1245,7 +1273,7 @@ retry:
                return 0;
 
        if (status == STATUS_SHORT_NAMES_NOT_ENABLED_ON_VOLUME) {
-               if (dentry->short_name_nbytes == 0)
+               if (dentry->d_short_name_nbytes == 0)
                        return 0;
                if (!ctx->tried_to_enable_short_names) {
                        wchar_t volume[7];
@@ -1279,7 +1307,7 @@ retry:
         *   from files.
         */
        if (unlikely(status == STATUS_OBJECT_NAME_COLLISION) &&
-           dentry->short_name_nbytes && !tried_to_remove_existing)
+           dentry->d_short_name_nbytes && !tried_to_remove_existing)
        {
                tried_to_remove_existing = true;
                status = remove_conflicting_short_name(dentry, ctx);
@@ -1290,7 +1318,7 @@ retry:
        /* By default, failure to set short names is not an error (since short
         * names aren't too important anymore...).  */
        if (!(ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES)) {
-               if (dentry->short_name_nbytes)
+               if (dentry->d_short_name_nbytes)
                        ctx->num_set_short_name_failures++;
                else
                        ctx->num_remove_short_name_failures++;
@@ -1464,44 +1492,104 @@ retry:
        return WIMLIB_ERR_OPEN;
 }
 
+/* Set the reparse point @rpbuf of length @rpbuflen on the extracted file
+ * corresponding to the WIM dentry @dentry.  */
+static int
+do_set_reparse_point(const struct wim_dentry *dentry,
+                    const struct reparse_buffer_disk *rpbuf, u16 rpbuflen,
+                    struct win32_apply_ctx *ctx)
+{
+       NTSTATUS status;
+       HANDLE h;
+
+       status = create_file(&h, GENERIC_WRITE, NULL,
+                            0, FILE_OPEN, 0, dentry, ctx);
+       if (!NT_SUCCESS(status))
+               goto fail;
+
+       status = (*func_NtFsControlFile)(h, NULL, NULL, NULL,
+                                        &ctx->iosb, FSCTL_SET_REPARSE_POINT,
+                                        (void *)rpbuf, rpbuflen,
+                                        NULL, 0);
+       (*func_NtClose)(h);
+
+       if (NT_SUCCESS(status))
+               return 0;
+
+       /* On Windows, by default only the Administrator can create symbolic
+        * links for some reason.  By default we just issue a warning if this
+        * appears to be the problem.  Use WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS
+        * to get a hard error.  */
+       if (!(ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS)
+           && (status == STATUS_PRIVILEGE_NOT_HELD ||
+               status == STATUS_ACCESS_DENIED)
+           && (dentry->d_inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
+               dentry->d_inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT))
+       {
+               WARNING("Can't create symbolic link \"%ls\"!              \n"
+                       "          (Need Administrator rights, or at least "
+                       "the\n"
+                       "          SeCreateSymbolicLink privilege.)",
+                       current_path(ctx));
+               return 0;
+       }
+
+fail:
+       winnt_error(status, L"Can't set reparse data on \"%ls\"",
+                   current_path(ctx));
+       return WIMLIB_ERR_SET_REPARSE_DATA;
+}
+
 /*
- * Create empty named data streams for the specified file, if there are any.
+ * Create empty named data streams and potentially a reparse point for the
+ * specified file, if any.
  *
  * Since these won't have blob descriptors, they won't show up in the call to
  * extract_blob_list().  Hence the need for the special case.
  */
 static int
-create_empty_named_data_streams(const struct wim_dentry *dentry,
-                               struct win32_apply_ctx *ctx)
+create_empty_streams(const struct wim_dentry *dentry,
+                    struct win32_apply_ctx *ctx)
 {
        const struct wim_inode *inode = dentry->d_inode;
-       bool path_modified = false;
-       int ret = 0;
-
-       if (!ctx->common.supported_features.named_data_streams)
-               return 0;
+       int ret;
 
        for (unsigned i = 0; i < inode->i_num_streams; i++) {
                const struct wim_inode_stream *strm = &inode->i_streams[i];
-               HANDLE h;
 
-               if (!stream_is_named_data_stream(strm) ||
-                   stream_blob_resolved(strm) != NULL)
+               if (stream_blob_resolved(strm) != NULL)
                        continue;
 
-               build_extraction_path_with_ads(dentry, ctx,
-                                              strm->stream_name,
-                                              utf16le_len_chars(strm->stream_name));
-               path_modified = true;
-               ret = supersede_file_or_stream(ctx, &h);
-               if (ret)
-                       break;
-               (*func_NtClose)(h);
+               if (strm->stream_type == STREAM_TYPE_REPARSE_POINT &&
+                   ctx->common.supported_features.reparse_points)
+               {
+                       u8 buf[REPARSE_DATA_OFFSET] _aligned_attribute(8);
+                       struct reparse_buffer_disk *rpbuf =
+                               (struct reparse_buffer_disk *)buf;
+                       complete_reparse_point(rpbuf, inode, 0);
+                       ret = do_set_reparse_point(dentry, rpbuf,
+                                                  REPARSE_DATA_OFFSET, ctx);
+                       if (ret)
+                               return ret;
+               } else if (stream_is_named_data_stream(strm) &&
+                          ctx->common.supported_features.named_data_streams)
+               {
+                       HANDLE h;
+
+                       build_extraction_path_with_ads(dentry, ctx,
+                                                      strm->stream_name,
+                                                      utf16le_len_chars(strm->stream_name));
+                       ret = supersede_file_or_stream(ctx, &h);
+
+                       build_extraction_path(dentry, ctx);
+
+                       if (ret)
+                               return ret;
+                       (*func_NtClose)(h);
+               }
        }
-       /* Restore the path to the dentry itself  */
-       if (path_modified)
-               build_extraction_path(dentry, ctx);
-       return ret;
+
+       return 0;
 }
 
 /*
@@ -1587,7 +1675,7 @@ create_directories(struct list_head *dentry_list,
                ret = create_directory(dentry, ctx);
 
                if (!ret)
-                       ret = create_empty_named_data_streams(dentry, ctx);
+                       ret = create_empty_streams(dentry, ctx);
 
                ret = check_apply_error(dentry, ctx, ret);
                if (ret)
@@ -1624,7 +1712,7 @@ create_nondirectory_inode(HANDLE *h_ret, const struct wim_dentry *dentry,
        if (ret)
                goto out_close;
 
-       ret = create_empty_named_data_streams(dentry, ctx);
+       ret = create_empty_streams(dentry, ctx);
        if (ret)
                goto out_close;
 
@@ -1736,7 +1824,7 @@ create_nondirectory(struct wim_inode *inode, struct win32_apply_ctx *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);
+               ret = set_backed_from_wim(h, inode, ctx);
 
        (*func_NtClose)(h);
        return ret;
@@ -1815,7 +1903,7 @@ begin_extract_blob_instance(const struct blob_descriptor *blob,
                 * data be available.  So, stage the data in a buffer.  */
                if (!prepare_data_buffer(ctx, blob->size))
                        return WIMLIB_ERR_NOMEM;
-               list_add_tail(&dentry->tmp_list, &ctx->reparse_dentries);
+               list_add_tail(&dentry->d_tmp_list, &ctx->reparse_dentries);
                return 0;
        }
 
@@ -1833,7 +1921,7 @@ begin_extract_blob_instance(const struct blob_descriptor *blob,
                 * such files...  */
                if (!prepare_data_buffer(ctx, blob->size))
                        return WIMLIB_ERR_NOMEM;
-               list_add_tail(&dentry->tmp_list, &ctx->encrypted_dentries);
+               list_add_tail(&dentry->d_tmp_list, &ctx->encrypted_dentries);
                return 0;
        }
 
@@ -1881,54 +1969,6 @@ begin_extract_blob_instance(const struct blob_descriptor *blob,
        return 0;
 }
 
-/* Set the reparse point @rpbuf of length @rpbuflen on the extracted file
- * corresponding to the WIM dentry @dentry.  */
-static int
-do_set_reparse_point(const struct wim_dentry *dentry,
-                    const struct reparse_buffer_disk *rpbuf, u16 rpbuflen,
-                    struct win32_apply_ctx *ctx)
-{
-       NTSTATUS status;
-       HANDLE h;
-
-       status = create_file(&h, GENERIC_WRITE, NULL,
-                            0, FILE_OPEN, 0, dentry, ctx);
-       if (!NT_SUCCESS(status))
-               goto fail;
-
-       status = (*func_NtFsControlFile)(h, NULL, NULL, NULL,
-                                        &ctx->iosb, FSCTL_SET_REPARSE_POINT,
-                                        (void *)rpbuf, rpbuflen,
-                                        NULL, 0);
-       (*func_NtClose)(h);
-
-       if (NT_SUCCESS(status))
-               return 0;
-
-       /* On Windows, by default only the Administrator can create symbolic
-        * links for some reason.  By default we just issue a warning if this
-        * appears to be the problem.  Use WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS
-        * to get a hard error.  */
-       if (!(ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS)
-           && (status == STATUS_PRIVILEGE_NOT_HELD ||
-               status == STATUS_ACCESS_DENIED)
-           && (dentry->d_inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
-               dentry->d_inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT))
-       {
-               WARNING("Can't create symbolic link \"%ls\"!              \n"
-                       "          (Need Administrator rights, or at least "
-                       "the\n"
-                       "          SeCreateSymbolicLink privilege.)",
-                       current_path(ctx));
-               return 0;
-       }
-
-fail:
-       winnt_error(status, L"Can't set reparse data on \"%ls\"",
-                   current_path(ctx));
-       return WIMLIB_ERR_SET_REPARSE_DATA;
-}
-
 /* Given a Windows NT namespace path, such as \??\e:\Windows\System32, return a
  * pointer to the suffix of the path that begins with the device directly, such
  * as e:\Windows\System32.  */
@@ -2214,6 +2254,236 @@ extract_chunk(const void *chunk, size_t size, void *_ctx)
        return 0;
 }
 
+static int
+get_system_compression_format(int extract_flags)
+{
+       if (extract_flags & WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS4K)
+               return FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS4K;
+
+       if (extract_flags & WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS8K)
+               return FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS8K;
+
+       if (extract_flags & WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS16K)
+               return FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS16K;
+
+       return FILE_PROVIDER_COMPRESSION_FORMAT_LZX;
+}
+
+
+static const wchar_t *
+get_system_compression_format_string(int format)
+{
+       switch (format) {
+       case FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS4K:
+               return L"XPRESS4K";
+       case FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS8K:
+               return L"XPRESS8K";
+       case FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS16K:
+               return L"XPRESS16K";
+       default:
+               return L"LZX";
+       }
+}
+
+static NTSTATUS
+set_system_compression(HANDLE h, int format)
+{
+       NTSTATUS status;
+       IO_STATUS_BLOCK iosb;
+       struct {
+               struct wof_external_info wof_info;
+               struct file_provider_external_info file_info;
+       } in = {
+               .wof_info = {
+                       .version = WOF_CURRENT_VERSION,
+                       .provider = WOF_PROVIDER_FILE,
+               },
+               .file_info = {
+                       .version = FILE_PROVIDER_CURRENT_VERSION,
+                       .compression_format = format,
+               },
+       };
+
+       /* We intentionally use NtFsControlFile() rather than DeviceIoControl()
+        * here because the "compressing this object would not save space"
+        * status code does not map to a valid Win32 error code on older
+        * versions of Windows (before Windows 10?).  This can be a problem if
+        * the WOFADK driver is being used rather than the regular WOF, since
+        * WOFADK can be used on older versions of Windows.  */
+       status = (*func_NtFsControlFile)(h, NULL, NULL, NULL, &iosb,
+                                        FSCTL_SET_EXTERNAL_BACKING,
+                                        &in, sizeof(in), NULL, 0);
+
+       if (status == 0xC000046F) /* "Compressing this object would not save space."  */
+               return STATUS_SUCCESS;
+
+       return status;
+}
+
+/* Hard-coded list of files which the Windows bootloader needs to access before
+ * the WOF driver has been loaded.  Since the Windows bootloader only supports
+ * the XPRESS4K variant of System Compression, such files should not be
+ * compressed using other variants.  */
+static wchar_t *xpress4k_only_pattern_strings[] = {
+       L"*winload.*",
+       L"*winresume.*",
+       L"\\Windows\\AppPatch\\drvmain.sdb",
+       L"\\Windows\\Fonts\\vgaoem.fon",
+       L"\\Windows\\Fonts\\vgasys.fon",
+       L"\\Windows\\INF\\errata.inf",
+       L"\\Windows\\System32\\config\\*",
+       L"\\Windows\\System32\\ntkrnlpa.exe",
+       L"\\Windows\\System32\\ntoskrnl.exe",
+       L"\\Windows\\System32\\bootvid.dll",
+       L"\\Windows\\System32\\ci.dll",
+       L"\\Windows\\System32\\hal*.dll",
+       L"\\Windows\\System32\\mcupdate_AuthenticAMD.dll",
+       L"\\Windows\\System32\\mcupdate_GenuineIntel.dll",
+       L"\\Windows\\System32\\pshed.dll",
+       L"\\Windows\\System32\\apisetschema.dll",
+       L"\\Windows\\System32\\api-ms-win*.dll",
+       L"\\Windows\\System32\\ext-ms-win*.dll",
+       L"\\Windows\\System32\\KernelBase.dll",
+       L"\\Windows\\System32\\drivers\\*.sys",
+       L"\\Windows\\System32\\*.nls",
+       L"\\Windows\\System32\\kbd*.dll",
+       L"\\Windows\\System32\\kd*.dll",
+       L"\\Windows\\System32\\clfs.sys",
+       L"\\Windows\\System32\\CodeIntegrity\\driver.stl",
+};
+
+static const struct string_set xpress4k_only_patterns = {
+       .strings = xpress4k_only_pattern_strings,
+       .num_strings = ARRAY_LEN(xpress4k_only_pattern_strings),
+};
+
+static NTSTATUS
+set_system_compression_on_inode(struct wim_inode *inode, int format,
+                               struct win32_apply_ctx *ctx)
+{
+       bool retried = false;
+       NTSTATUS status;
+       HANDLE h;
+
+       /* If needed, force the XPRESS4K format for this file.  */
+       if (format != FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS4K) {
+               /* We need to check the patterns against every name of the
+                * inode, in case any of them match.  */
+               struct wim_dentry *dentry;
+               inode_for_each_extraction_alias(dentry, inode) {
+                       bool incompatible;
+
+                       if (calculate_dentry_full_path(dentry)) {
+                               ERROR("Unable to compute file path!");
+                               return STATUS_NO_MEMORY;
+                       }
+
+                       incompatible = match_pattern_list(dentry->d_full_path,
+                                                         &xpress4k_only_patterns);
+                       FREE(dentry->d_full_path);
+                       dentry->d_full_path = NULL;
+
+                       if (incompatible) {
+                               if (ctx->num_xpress4k_forced_files++ == 0) {
+                                       WARNING("For compatibility with the "
+                                               "Windows bootloader, some "
+                                               "files are being\n"
+                                               "          compacted "
+                                               "using the XPRESS4K format "
+                                               "instead of the %"TS" format\n"
+                                               "          you requested.",
+                                               get_system_compression_format_string(format));
+                               }
+                               format = FILE_PROVIDER_COMPRESSION_FORMAT_XPRESS4K;
+                               break;
+                       }
+               }
+       }
+
+       /* Open the extracted file.  */
+       status = create_file(&h, GENERIC_READ | GENERIC_WRITE, NULL,
+                            0, FILE_OPEN, 0,
+                            inode_first_extraction_dentry(inode), ctx);
+
+       if (!NT_SUCCESS(status))
+               return status;
+retry:
+       /* Compress the file.  If the attempt fails with "invalid device
+        * request", then attach wof.sys (or wofadk.sys) and retry.  */
+       status = set_system_compression(h, format);
+       if (unlikely(status == STATUS_INVALID_DEVICE_REQUEST && !retried)) {
+               wchar_t drive_path[7];
+               if (!win32_get_drive_path(ctx->common.target, drive_path) &&
+                   win32_try_to_attach_wof(drive_path + 4)) {
+                       retried = true;
+                       goto retry;
+               }
+       }
+
+       (*func_NtClose)(h);
+       return status;
+}
+
+/*
+ * This function is called when doing a "compact-mode" extraction and we just
+ * finished extracting a blob to one or more locations.  For each location that
+ * was the unnamed data stream of a file, this function compresses the
+ * corresponding file using System Compression, if allowed.
+ *
+ * Note: we're doing the compression immediately after extracting the data
+ * rather than during a separate compression pass.  This way should be faster
+ * since the operating system should still have the file's data cached.
+ *
+ * Note: we're having the operating system do the compression, which is not
+ * ideal because wimlib could create the compressed data faster and more
+ * efficiently (the compressed data format is identical to a WIM resource).  But
+ * we seemingly don't have a choice because WOF prevents applications from
+ * creating its reparse points.
+ */
+static void
+handle_system_compression(struct blob_descriptor *blob, struct win32_apply_ctx *ctx)
+{
+       const struct blob_extraction_target *targets = blob_extraction_targets(blob);
+
+       const int format = get_system_compression_format(ctx->common.extract_flags);
+
+       for (u32 i = 0; i < blob->out_refcnt; i++) {
+               struct wim_inode *inode = targets[i].inode;
+               struct wim_inode_stream *strm = targets[i].stream;
+               NTSTATUS status;
+
+               if (!stream_is_unnamed_data_stream(strm))
+                       continue;
+
+               if (will_externally_back_inode(inode, ctx, NULL, false) != 0)
+                       continue;
+
+               status = set_system_compression_on_inode(inode, format, ctx);
+               if (likely(NT_SUCCESS(status)))
+                       continue;
+
+               if (status == STATUS_INVALID_DEVICE_REQUEST) {
+                       WARNING(
+         "The request to compress the extracted files using System Compression\n"
+"          will not be honored because the operating system or target volume\n"
+"          does not support it.  System Compression is only supported on\n"
+"          Windows 10 and later, and only on NTFS volumes.");
+                       ctx->common.extract_flags &= ~COMPACT_FLAGS;
+                       return;
+               }
+
+               ctx->num_system_compression_failures++;
+               if (ctx->num_system_compression_failures < 10) {
+                       winnt_warning(status, L"\"%ls\": Failed to compress "
+                                     "extracted file using System Compression",
+                                     current_path(ctx));
+               } else if (ctx->num_system_compression_failures == 10) {
+                       WARNING("Suppressing further warnings about "
+                               "System Compression failures.");
+               }
+       }
+}
+
 /* Called when a blob has been fully read for extraction on Windows  */
 static int
 end_extract_blob(struct blob_descriptor *blob, int status, void *_ctx)
@@ -2227,13 +2497,16 @@ end_extract_blob(struct blob_descriptor *blob, int status, void *_ctx)
        if (status)
                return status;
 
+       if (unlikely(ctx->common.extract_flags & COMPACT_FLAGS))
+               handle_system_compression(blob, ctx);
+
        if (likely(!ctx->data_buffer_ptr))
                return 0;
 
        if (!list_empty(&ctx->reparse_dentries)) {
                if (blob->size > REPARSE_DATA_MAX_SIZE) {
                        dentry = list_first_entry(&ctx->reparse_dentries,
-                                                 struct wim_dentry, tmp_list);
+                                                 struct wim_dentry, d_tmp_list);
                        build_extraction_path(dentry, ctx);
                        ERROR("Reparse data of \"%ls\" has size "
                              "%"PRIu64" bytes (exceeds %u bytes)",
@@ -2245,7 +2518,7 @@ end_extract_blob(struct blob_descriptor *blob, int status, void *_ctx)
                /* Reparse data  */
                memcpy(ctx->rpbuf.rpdata, ctx->data_buffer, blob->size);
 
-               list_for_each_entry(dentry, &ctx->reparse_dentries, tmp_list) {
+               list_for_each_entry(dentry, &ctx->reparse_dentries, d_tmp_list) {
 
                        /* Reparse point header  */
                        complete_reparse_point(&ctx->rpbuf, dentry->d_inode,
@@ -2262,7 +2535,7 @@ end_extract_blob(struct blob_descriptor *blob, int status, void *_ctx)
 
        if (!list_empty(&ctx->encrypted_dentries)) {
                ctx->encrypted_size = blob->size;
-               list_for_each_entry(dentry, &ctx->encrypted_dentries, tmp_list) {
+               list_for_each_entry(dentry, &ctx->encrypted_dentries, d_tmp_list) {
                        ret = extract_encrypted_file(dentry, ctx);
                        ret = check_apply_error(dentry, ctx, ret);
                        if (ret)
@@ -2680,11 +2953,11 @@ out:
        FREE(ctx->pathbuf.Buffer);
        FREE(ctx->print_buffer);
        FREE(ctx->wimboot.wims);
-       if (ctx->wimboot.prepopulate_pats) {
-               FREE(ctx->wimboot.prepopulate_pats->strings);
-               FREE(ctx->wimboot.prepopulate_pats);
+       if (ctx->prepopulate_pats) {
+               FREE(ctx->prepopulate_pats->strings);
+               FREE(ctx->prepopulate_pats);
        }
-       FREE(ctx->wimboot.mem_prepopulate_pats);
+       FREE(ctx->mem_prepopulate_pats);
        FREE(ctx->data_buffer);
        return ret;
 }
@@ -2693,7 +2966,7 @@ const struct apply_operations win32_apply_ops = {
        .name                   = "Windows",
        .get_supported_features = win32_get_supported_features,
        .extract                = win32_extract,
-       .will_externally_back   = win32_will_externally_back,
+       .will_back_from_wim     = win32_will_back_from_wim,
        .context_size           = sizeof(struct win32_apply_ctx),
 };