]> wimlib.net Git - wimlib/blobdiff - src/win32_apply.c
Capture and apply extended attributes on Windows
[wimlib] / src / win32_apply.c
index 94285aca793cf763cd1cf377ecaace6be4eb1bcf..1434bd22d8d656969d03cc1fe829538199d77096 100644 (file)
@@ -3,7 +3,7 @@
  */
 
 /*
- * Copyright (C) 2013-2016 Eric Biggers
+ * Copyright (C) 2013-2018 Eric Biggers
  *
  * 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
 #include "wimlib/reparse.h"
 #include "wimlib/scan.h" /* for mangle_pat() and match_pattern_list()  */
 #include "wimlib/textfile.h"
-#include "wimlib/xml.h"
 #include "wimlib/wimboot.h"
 #include "wimlib/wof.h"
+#include "wimlib/xattr.h"
+#include "wimlib/xml.h"
 
 struct win32_apply_ctx {
 
@@ -169,6 +170,9 @@ struct win32_apply_ctx {
        /* Number of files for which we couldn't set the object ID.  */
        unsigned long num_object_id_failures;
 
+       /* Number of files for which we couldn't set extended attributes.  */
+       unsigned long num_xattr_failures;
+
        /* The Windows build number of the image being applied, or 0 if unknown.
         */
        u64 windows_build_number;
@@ -225,9 +229,14 @@ get_vol_flags(const wchar_t *target, DWORD *vol_flags_ret,
        }
 
        if (wcsstr(filesystem_name, L"NTFS")) {
-               /* FILE_SUPPORTS_HARD_LINKS is only supported on Windows 7 and
-                * later.  Force it on anyway if filesystem is NTFS.  */
+               /*
+                * FILE_SUPPORTS_HARD_LINKS and
+                * FILE_SUPPORTS_EXTENDED_ATTRIBUTES are only supported on
+                * Windows 7 and later.  Force them on anyway if the filesystem
+                * is NTFS.
+                */
                *vol_flags_ret |= FILE_SUPPORTS_HARD_LINKS;
+               *vol_flags_ret |= FILE_SUPPORTS_EXTENDED_ATTRIBUTES;
 
                /* There's no volume flag for short names, but according to the
                 * MS documentation they are only user-settable on NTFS.  */
@@ -339,6 +348,9 @@ win32_get_supported_features(const wchar_t *target,
                        supported_features->case_sensitive_filenames = 1;
        }
 
+       if (vol_flags & FILE_SUPPORTS_EXTENDED_ATTRIBUTES)
+               supported_features->xattrs = 1;
+
        return 0;
 }
 
@@ -2805,6 +2817,105 @@ set_object_id(HANDLE h, const struct wim_inode *inode,
        }
 }
 
+static int
+set_xattrs(HANDLE h, const struct wim_inode *inode, struct win32_apply_ctx *ctx)
+{
+       const void *entries, *entries_end;
+       u32 len;
+       const struct wim_xattr_entry *entry;
+       size_t bufsize = 0;
+       u8 _buf[1024] _aligned_attribute(4);
+       u8 *buf = _buf;
+       FILE_FULL_EA_INFORMATION *ea, *ea_prev;
+       NTSTATUS status;
+       int ret;
+
+       if (!ctx->common.supported_features.xattrs)
+               return 0;
+
+       entries = inode_get_xattrs(inode, &len);
+       if (likely(entries == NULL || len == 0))  /* No extended attributes? */
+               return 0;
+       entries_end = entries + len;
+
+       entry = entries;
+       for (entry = entries; (void *)entry < entries_end;
+            entry = xattr_entry_next(entry)) {
+               if (!valid_xattr_entry(entry, entries_end - (void *)entry)) {
+                       ERROR("\"%"TS"\": extended attribute is corrupt or unsupported",
+                             inode_any_full_path(inode));
+                       return WIMLIB_ERR_INVALID_XATTR;
+               }
+
+               bufsize += ALIGN(offsetof(FILE_FULL_EA_INFORMATION, EaName) +
+                                entry->name_len + 1 +
+                                le16_to_cpu(entry->value_len), 4);
+       }
+
+       if (unlikely(bufsize != (u32)bufsize)) {
+               ERROR("\"%"TS"\": too many extended attributes to extract!",
+                     inode_any_full_path(inode));
+               return WIMLIB_ERR_INVALID_XATTR;
+       }
+
+       if (unlikely(bufsize > sizeof(_buf))) {
+               buf = MALLOC(bufsize);
+               if (!buf)
+                       return WIMLIB_ERR_NOMEM;
+       }
+
+       ea_prev = NULL;
+       ea = (FILE_FULL_EA_INFORMATION *)buf;
+       for (entry = entries; (void *)entry < entries_end;
+            entry = xattr_entry_next(entry)) {
+               u8 *p;
+
+               if (ea_prev)
+                       ea_prev->NextEntryOffset = (u8 *)ea - (u8 *)ea_prev;
+               ea->Flags = entry->flags;
+               ea->EaNameLength = entry->name_len;
+               ea->EaValueLength = le16_to_cpu(entry->value_len);
+               p = mempcpy(ea->EaName, entry->name,
+                           ea->EaNameLength + 1 + ea->EaValueLength);
+               while ((uintptr_t)p & 3)
+                       *p++ = 0;
+               ea_prev = ea;
+               ea = (FILE_FULL_EA_INFORMATION *)p;
+       }
+       ea_prev->NextEntryOffset = 0;
+       wimlib_assert((u8 *)ea - buf == bufsize);
+
+       status = NtSetEaFile(h, &ctx->iosb, buf, bufsize);
+       if (unlikely(!NT_SUCCESS(status))) {
+               if (status == STATUS_EAS_NOT_SUPPORTED) {
+                       /* This happens with Samba. */
+                       WARNING("Filesystem advertised extended attribute (EA) support, but it doesn't\n"
+                               "          work.  EAs will not be extracted.");
+                       ctx->common.supported_features.xattrs = 0;
+               } else if (status == STATUS_INVALID_EA_NAME) {
+                       ctx->num_xattr_failures++;
+                       if (ctx->num_xattr_failures < 5) {
+                               winnt_warning(status,
+                                             L"Can't set extended attributes on \"%ls\"",
+                                             current_path(ctx));
+                       } else if (ctx->num_xattr_failures == 5) {
+                               WARNING("Suppressing further warnings about "
+                                       "failure to set extended attributes.");
+                       }
+               } else {
+                       winnt_error(status, L"Can't set extended attributes on \"%ls\"",
+                                   current_path(ctx));
+                       ret = WIMLIB_ERR_SET_XATTR;
+                       goto out;
+               }
+       }
+       ret = 0;
+out:
+       if (buf != _buf)
+               FREE(buf);
+       return ret;
+}
+
 /* Set the security descriptor @desc, of @desc_size bytes, on the file with open
  * handle @h.  */
 static NTSTATUS
@@ -2948,11 +3059,18 @@ do_apply_metadata_to_file(HANDLE h, const struct wim_inode *inode,
 {
        FILE_BASIC_INFORMATION info;
        NTSTATUS status;
+       int ret;
 
        /* Set the file's object ID if present and object IDs are supported by
         * the filesystem.  */
        set_object_id(h, inode, ctx);
 
+       /* Set the file's extended attributes (EAs) if present and EAs are
+        * supported by the filesystem.  */
+       ret = set_xattrs(h, inode, ctx);
+       if (ret)
+               return ret;
+
        /* Set the file's security descriptor if present and we're not in
         * NO_ACLS mode  */
        if (inode_has_security_descriptor(inode) &&
@@ -3017,7 +3135,7 @@ apply_metadata_to_file(const struct wim_dentry *dentry,
        NTSTATUS status;
        int ret;
 
-       perms = FILE_WRITE_ATTRIBUTES | WRITE_DAC |
+       perms = FILE_WRITE_ATTRIBUTES | FILE_WRITE_EA | WRITE_DAC |
                WRITE_OWNER | ACCESS_SYSTEM_SECURITY;
 
        build_extraction_path(dentry, ctx);