]> wimlib.net Git - wimlib/blobdiff - src/win32_apply.c
WIMBoot: Update WimOverlay.dat directly when WOF not running
[wimlib] / src / win32_apply.c
index b7646651efd5d08040dda18cad4d0e4ed0064e1d..48ff5d87e01efa609745090195cd0903546a75ca 100644 (file)
 #include "wimlib/win32_common.h"
 
 #include "wimlib/apply.h"
+#include "wimlib/capture.h"
+#include "wimlib/dentry.h"
 #include "wimlib/error.h"
 #include "wimlib/lookup_table.h"
+#include "wimlib/paths.h"
+#include "wimlib/resource.h"
+#include "wimlib/textfile.h"
+#include "wimlib/xml.h"
+#include "wimlib/wim.h"
+#include "wimlib/wimboot.h"
+
+struct win32_apply_private_data {
+       u64 data_source_id;
+       struct string_set *prepopulate_pats;
+       void *mem_prepopulate_pats;
+       u8 wim_lookup_table_hash[SHA1_HASH_SIZE];
+       bool wof_running;
+};
+
+static struct win32_apply_private_data *
+get_private_data(struct apply_ctx *ctx)
+{
+       BUILD_BUG_ON(sizeof(ctx->private) < sizeof(struct win32_apply_private_data));
+       return (struct win32_apply_private_data *)(ctx->private);
+}
+
+static void
+free_prepopulate_pats(struct win32_apply_private_data *dat)
+{
+       if (dat->prepopulate_pats) {
+               FREE(dat->prepopulate_pats->strings);
+               FREE(dat->prepopulate_pats);
+               dat->prepopulate_pats = NULL;
+       }
+
+       if (dat->mem_prepopulate_pats) {
+               FREE(dat->mem_prepopulate_pats);
+               dat->mem_prepopulate_pats = NULL;
+       }
+}
+
+static int
+load_prepopulate_pats(struct apply_ctx *ctx)
+{
+       int ret;
+       struct wim_dentry *dentry;
+       struct wim_lookup_table_entry *lte;
+       struct string_set *s;
+       const tchar *path = WIMLIB_WIM_PATH_SEPARATOR_STRING T("Windows")
+                           WIMLIB_WIM_PATH_SEPARATOR_STRING T("System32")
+                           WIMLIB_WIM_PATH_SEPARATOR_STRING T("WimBootCompress.ini");
+       void *buf;
+       void *mem;
+       struct text_file_section sec;
+       struct win32_apply_private_data *dat = get_private_data(ctx);
+
+       dentry = get_dentry(ctx->wim, path, WIMLIB_CASE_INSENSITIVE);
+       if (!dentry ||
+           (dentry->d_inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
+                                             FILE_ATTRIBUTE_REPARSE_POINT |
+                                             FILE_ATTRIBUTE_ENCRYPTED)) ||
+           !(lte = inode_unnamed_lte(dentry->d_inode, ctx->wim->lookup_table)))
+       {
+               WARNING("%"TS" does not exist in WIM image!", path);
+               return WIMLIB_ERR_PATH_DOES_NOT_EXIST;
+       }
+
+       ret = read_full_stream_into_alloc_buf(lte, &buf);
+       if (ret)
+               return ret;
+
+       s = CALLOC(1, sizeof(struct string_set));
+       if (!s) {
+               FREE(buf);
+               return WIMLIB_ERR_NOMEM;
+       }
+
+       sec.name = T("PrepopulateList");
+       sec.strings = s;
+
+       ret = do_load_text_file(path, buf, lte->size, &mem, &sec, 1,
+                               LOAD_TEXT_FILE_REMOVE_QUOTES |
+                                       LOAD_TEXT_FILE_NO_WARNINGS,
+                               mangle_pat);
+       FREE(buf);
+       if (ret) {
+               FREE(s);
+               return ret;
+       }
+       dat->prepopulate_pats = s;
+       dat->mem_prepopulate_pats = mem;
+       return 0;
+}
+
+static bool
+in_prepopulate_list(struct wim_dentry *dentry, struct apply_ctx *ctx)
+{
+       struct string_set *pats;
+       const tchar *path;
+
+       pats = get_private_data(ctx)->prepopulate_pats;
+       if (!pats)
+               return false;
+       path = dentry_full_path(dentry);
+       if (!path)
+               return false;
+
+       return match_pattern(path, path_basename(path), pats);
+}
+
+static int
+hash_lookup_table(WIMStruct *wim, u8 hash[SHA1_HASH_SIZE])
+{
+       return wim_reshdr_to_hash(&wim->hdr.lookup_table_reshdr, wim, hash);
+}
 
 static int
 win32_start_extract(const wchar_t *path, struct apply_ctx *ctx)
@@ -39,10 +152,11 @@ win32_start_extract(const wchar_t *path, struct apply_ctx *ctx)
        int ret;
        unsigned vol_flags;
        bool supports_SetFileShortName;
+       struct win32_apply_private_data *dat = get_private_data(ctx);
 
        ret = win32_get_vol_flags(path, &vol_flags, &supports_SetFileShortName);
        if (ret)
-               return ret;
+               goto err;
 
        ctx->supported_features.archive_files = 1;
        ctx->supported_features.hidden_files = 1;
@@ -78,61 +192,108 @@ win32_start_extract(const wchar_t *path, struct apply_ctx *ctx)
 
        if (supports_SetFileShortName)
                ctx->supported_features.short_names = 1;
+
+       if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT) {
+
+               ret = load_prepopulate_pats(ctx);
+               if (ret == WIMLIB_ERR_NOMEM)
+                       goto err;
+
+               if (!wim_info_get_wimboot(ctx->wim->wim_info,
+                                         ctx->wim->current_image))
+                       WARNING("Image is not marked as WIMBoot compatible!");
+
+
+               ret = hash_lookup_table(ctx->wim, dat->wim_lookup_table_hash);
+               if (ret)
+                       goto err;
+
+               ret = wimboot_alloc_data_source_id(ctx->wim->filename,
+                                                  ctx->wim->hdr.guid,
+                                                  ctx->wim->current_image,
+                                                  path,
+                                                  &dat->data_source_id,
+                                                  &dat->wof_running);
+               if (ret)
+                       goto err;
+       }
+
        return 0;
+
+err:
+       free_prepopulate_pats(dat);
+       return ret;
 }
 
+static int
+win32_finish_extract(struct apply_ctx *ctx)
+{
+       free_prepopulate_pats(get_private_data(ctx));
+       return 0;
+}
+
+/* Delete a non-directory file, working around Windows quirks.  */
+static BOOL
+win32_delete_file_wrapper(const wchar_t *path)
+{
+       DWORD err;
+       DWORD attrib;
+
+       if (DeleteFile(path))
+               return TRUE;
+
+       err = GetLastError();
+       attrib = GetFileAttributes(path);
+       if ((attrib != INVALID_FILE_ATTRIBUTES) &&
+           (attrib & FILE_ATTRIBUTE_READONLY))
+       {
+               /* Try again with FILE_ATTRIBUTE_READONLY cleared.  */
+               attrib &= ~FILE_ATTRIBUTE_READONLY;
+               if (SetFileAttributes(path, attrib)) {
+                       if (DeleteFile(path))
+                               return TRUE;
+                       else
+                               err = GetLastError();
+               }
+       }
+
+       SetLastError(err);
+       return FALSE;
+}
+
+
 /* Create a normal file, overwriting one already present.  */
 static int
 win32_create_file(const wchar_t *path, struct apply_ctx *ctx, u64 *cookie_ret)
 {
        HANDLE h;
-       unsigned retry_count = 0;
-       DWORD dwFlagsAndAttributes = FILE_FLAG_BACKUP_SEMANTICS;
 
+       /* Notes:
+        *
+        * WRITE_OWNER and WRITE_DAC privileges are required for some reason,
+        * even through we're creating a new file.
+        *
+        * FILE_FLAG_OPEN_REPARSE_POINT is required to prevent an existing
+        * reparse point from redirecting the creation of the new file
+        * (potentially to an arbitrary location).
+        *
+        * CREATE_ALWAYS could be used instead of CREATE_NEW.  However, there
+        * are quirks that would need to be handled (e.g. having to set
+        * FILE_ATTRIBUTE_HIDDEN and/or FILE_ATTRIBUTE_SYSTEM if the existing
+        * file had them specified, and/or having to clear
+        * FILE_ATTRIBUTE_READONLY on the existing file).  It's simpler to just
+        * call win32_delete_file_wrapper() to delete the existing file in such
+        * a way that already handles the FILE_ATTRIBUTE_READONLY quirk.
+        */
 retry:
-       /* WRITE_OWNER and WRITE_DAC privileges are required for some reason,
-        * even through we're creating a new file.  */
-       h = CreateFile(path, WRITE_OWNER | WRITE_DAC, 0, NULL,
-                      CREATE_ALWAYS, dwFlagsAndAttributes, NULL);
+       h = CreateFile(path, WRITE_OWNER | WRITE_DAC, 0, NULL, CREATE_NEW,
+                      FILE_FLAG_BACKUP_SEMANTICS |
+                               FILE_FLAG_OPEN_REPARSE_POINT, NULL);
        if (h == INVALID_HANDLE_VALUE) {
-               /* File couldn't be created.  */
                DWORD err = GetLastError();
-               if (err == ERROR_ACCESS_DENIED && retry_count == 0) {
-
-                       /* Access denied error for the first time.  Try
-                        * adjusting file attributes.  */
 
-                       /* Get attributes of the existing file.  */
-                       DWORD attribs = GetFileAttributes(path);
-                       if (attribs != INVALID_FILE_ATTRIBUTES &&
-                           (attribs & (FILE_ATTRIBUTE_HIDDEN |
-                                       FILE_ATTRIBUTE_SYSTEM |
-                                       FILE_ATTRIBUTE_READONLY)))
-                       {
-                               /* If the existing file has
-                                * FILE_ATTRIBUTE_HIDDEN and/or
-                                * FILE_ATTRIBUTE_SYSTEM, they must be set in
-                                * the call to CreateFile().  This is true even
-                                * when FILE_ATTRIBUTE_NORMAL was not specified,
-                                * contrary to the MS "documentation".  */
-                               dwFlagsAndAttributes |= (attribs &
-                                                        (FILE_ATTRIBUTE_HIDDEN |
-                                                         FILE_ATTRIBUTE_SYSTEM));
-                               /* If the existing file has
-                                * FILE_ATTRIBUTE_READONLY, it must be cleared
-                                * before attempting to create a new file over
-                                * it.  This is true even when the process has
-                                * the SE_RESTORE_NAME privilege and requested
-                                * the FILE_FLAG_BACKUP_SEMANTICS flag to
-                                * CreateFile().  */
-                               if (attribs & FILE_ATTRIBUTE_READONLY) {
-                                       SetFileAttributes(path,
-                                                         attribs & ~FILE_ATTRIBUTE_READONLY);
-                               }
-                               retry_count++;
-                               goto retry;
-                       }
-               }
+               if (err == ERROR_FILE_EXISTS && win32_delete_file_wrapper(path))
+                       goto retry;
                set_errno_from_win32_error(err);
                return WIMLIB_ERR_OPEN;
        }
@@ -161,7 +322,7 @@ win32_create_hardlink(const wchar_t *oldpath, const wchar_t *newpath,
        if (!CreateHardLink(newpath, oldpath, NULL)) {
                if (GetLastError() != ERROR_ALREADY_EXISTS)
                        goto error;
-               if (!DeleteFile(newpath))
+               if (!win32_delete_file_wrapper(newpath))
                        goto error;
                if (!CreateHardLink(newpath, oldpath, NULL))
                        goto error;
@@ -180,7 +341,7 @@ win32_create_symlink(const wchar_t *oldpath, const wchar_t *newpath,
        if (!(*win32func_CreateSymbolicLinkW)(newpath, oldpath, 0)) {
                if (GetLastError() != ERROR_ALREADY_EXISTS)
                        goto error;
-               if (!DeleteFile(newpath))
+               if (!win32_delete_file_wrapper(newpath))
                        goto error;
                if (!(*win32func_CreateSymbolicLinkW)(newpath, oldpath, 0))
                        goto error;
@@ -253,8 +414,25 @@ error:
 static int
 win32_extract_unnamed_stream(file_spec_t file,
                             struct wim_lookup_table_entry *lte,
-                            struct apply_ctx *ctx)
+                            struct apply_ctx *ctx,
+                            struct wim_dentry *dentry)
 {
+       if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT
+           && lte
+           && lte->resource_location == RESOURCE_IN_WIM
+           && lte->rspec->wim == ctx->wim
+           && lte->size == lte->rspec->uncompressed_size
+           && !in_prepopulate_list(dentry, ctx))
+       {
+               const struct win32_apply_private_data *dat;
+
+               dat = get_private_data(ctx);
+               return wimboot_set_pointer(file.path, lte,
+                                          dat->data_source_id,
+                                          dat->wim_lookup_table_hash,
+                                          dat->wof_running);
+       }
+
        return win32_extract_stream(file.path, NULL, 0, lte, ctx);
 }
 
@@ -523,37 +701,118 @@ do_win32_set_security_descriptor(HANDLE h, const wchar_t *path,
                return GetLastError();
 }
 
+/*
+ * Set an arbitrary security descriptor on an arbitrary file (or directory),
+ * working around bugs and design flaws in the Windows operating system.
+ *
+ * On success, return 0.  On failure, return WIMLIB_ERR_SET_SECURITY and set
+ * errno.  Note: if WIMLIB_EXTRACT_FLAG_STRICT_ACLS is not set in
+ * ctx->extract_flags, this function succeeds iff any part of the security
+ * descriptor was successfully set.
+ */
 static int
 win32_set_security_descriptor(const wchar_t *path, const u8 *desc,
                              size_t desc_size, struct apply_ctx *ctx)
 {
        SECURITY_INFORMATION info;
        HANDLE h;
-       DWORD err;
        int ret;
 
+       /* 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;
+
        h = INVALID_HANDLE_VALUE;
 
+       /* 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".)  */
+
 #ifdef WITH_NTDLL
        if (func_NtSetSecurityObject) {
-               h = win32_open_existing_file(path, MAXIMUM_ALLOWED);
-               if (h == INVALID_HANDLE_VALUE) {
-                       set_errno_from_GetLastError();
-                       ERROR_WITH_ERRNO("Can't open %ls", path);
+               DWORD dwDesiredAccess;
+
+               /* Open a handle for NtSetSecurityObject() with as many relevant
+                * access rights as possible.
+                *
+                * We don't know which rights will be actually granted.  It
+                * could be less than what is needed to actually assign the full
+                * security descriptor, especially if the process is running as
+                * a non-Administrator.  However, by default we just do the best
+                * we can, unless WIMLIB_EXTRACT_FLAG_STRICT_ACLS has been
+                * enabled.  The MAXIMUM_ALLOWED access right is seemingly
+                * designed for this use case; however, it does not work
+                * properly in all cases: it can cause CreateFile() to fail with
+                * ERROR_ACCESS_DENIED, even though by definition
+                * MAXIMUM_ALLOWED access only requests access rights that are
+                * *not* denied.  (Needless to say, MS does not document this
+                * bug.)  */
+
+               dwDesiredAccess = WRITE_DAC |
+                                 WRITE_OWNER |
+                                 ACCESS_SYSTEM_SECURITY;
+               for (;;) {
+                       DWORD err;
+
+                       h = win32_open_existing_file(path, dwDesiredAccess);
+                       if (h != INVALID_HANDLE_VALUE)
+                               break;
+                       err = GetLastError();
+                       if (err == ERROR_ACCESS_DENIED ||
+                           err == ERROR_PRIVILEGE_NOT_HELD)
+                       {
+                               /* Don't increment partial_security_descriptors
+                                * here or check WIMLIB_EXTRACT_FLAG_STRICT_ACLS
+                                * here.  It will be done later if needed; here
+                                * we are just trying to get as many relevant
+                                * access rights as possible.  */
+                               if (dwDesiredAccess & ACCESS_SYSTEM_SECURITY) {
+                                       dwDesiredAccess &= ~ACCESS_SYSTEM_SECURITY;
+                                       continue;
+                               }
+                               if (dwDesiredAccess & WRITE_DAC) {
+                                       dwDesiredAccess &= ~WRITE_DAC;
+                                       continue;
+                               }
+                               if (dwDesiredAccess & WRITE_OWNER) {
+                                       dwDesiredAccess &= ~WRITE_OWNER;
+                                       continue;
+                               }
+                       }
+                       /* Other error, or couldn't open the file even with no
+                        * access rights specified.  Something else must be
+                        * wrong.  */
+                       set_errno_from_win32_error(err);
                        return WIMLIB_ERR_SET_SECURITY;
                }
        }
 #endif
 
+       /* Try setting the security descriptor.  */
        for (;;) {
+               DWORD err;
+
                err = do_win32_set_security_descriptor(h, path, info,
                                                       (PSECURITY_DESCRIPTOR)desc);
                if (err == ERROR_SUCCESS) {
                        ret = 0;
                        break;
                }
+
+               /* 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.  */
                if ((err == ERROR_PRIVILEGE_NOT_HELD ||
                     err == ERROR_ACCESS_DENIED) &&
                    !(ctx->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
@@ -571,15 +830,20 @@ win32_set_security_descriptor(const wchar_t *path, const u8 *desc,
                                info &= ~OWNER_SECURITY_INFORMATION;
                                continue;
                        }
-                       ctx->partial_security_descriptors--;
-                       ctx->no_security_descriptors++;
-                       ret = 0;
-                       break;
+                       /* Nothing left except GROUP, and if we removed it we
+                        * wouldn't have anything at all.  */
                }
+               /* No part of the security descriptor could be set, or
+                * WIMLIB_EXTRACT_FLAG_STRICT_ACLS is enabled and the full
+                * security descriptor could not be set.  */
+               if (!(info & SACL_SECURITY_INFORMATION))
+                       ctx->partial_security_descriptors--;
                set_errno_from_win32_error(err);
                ret = WIMLIB_ERR_SET_SECURITY;
                break;
        }
+
+       /* Close handle opened for NtSetSecurityObject().  */
 #ifdef WITH_NTDLL
        if (func_NtSetSecurityObject)
                CloseHandle(h);
@@ -627,6 +891,8 @@ const struct apply_operations win32_apply_ops = {
 
        .target_is_root           = win32_path_is_root_of_drive,
        .start_extract            = win32_start_extract,
+       .finish_extract           = win32_finish_extract,
+       .abort_extract            = win32_finish_extract,
        .create_file              = win32_create_file,
        .create_directory         = win32_create_directory,
        .create_hardlink          = win32_create_hardlink,