*/
/*
- * Copyright (C) 2014 Eric Biggers
+ * Copyright (C) 2014-2016 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 HAVE_CONFIG_H
# include "config.h"
#endif
+#include "wimlib/assert.h"
#include "wimlib/endianness.h"
#include "wimlib/inode.h"
-#include "wimlib/types.h"
+#include "wimlib/tagged_items.h"
#include "wimlib/unix_data.h"
-/* Used by the Microsoft implementation. */
-#define TAG_OBJECT_ID 0x00000001
-
-/* Random number that we'll use for tagging our UNIX data items. */
-#define TAG_WIMLIB_UNIX_DATA 0x337DD873
-
-/* Header that begins each tagged metadata item in the metadata resource */
+/*
+ * Header that begins each tagged metadata item associated with a file in a WIM
+ * metadata resource
+ */
struct tagged_item_header {
- /* Unique identifier for this item. */
+ /* identifies the type of metadata item (see TAG_* constants) */
le32 tag;
- /* Size of the data of this tagged item, in bytes. This excludes this
- * header and should be a multiple of 8.
- *
- * (Actually, the MS implementation seems to round this up to an 8 byte
- * boundary when calculating the offset to the next tagged item, but
- * uses this length unmodified when validating the item. We might as
- * well do the same.) */
+ /* size of this item's data in bytes, excluding this header */
le32 length;
- /* Variable length data */
- u8 data[];
-};
-
-struct object_id_disk {
- u8 object_id[16];
- u8 birth_volume_id[16];
- u8 birth_object_id[16];
- u8 domain_id[16];
-};
+ /* followed by the item's data */
+ u8 data[0];
-struct wimlib_unix_data_disk {
- le32 uid;
- le32 gid;
- le32 mode;
- le32 rdev;
-};
+ /* then zero-padded to an 8-byte boundary */
+} _aligned_attribute(8);
-/* Retrieves the first tagged item with the specified tag and minimum length
- * from the WIM inode. Returns a pointer to the tagged data, which can be read
- * and/or modified in place. Or, if no matching tagged item is found, returns
- * NULL. */
-static void *
-inode_get_tagged_item(const struct wim_inode *inode,
- u32 desired_tag, u32 min_data_len)
+/*
+ * Retrieve from @inode the first metadata item that is tagged with @tag and
+ * contains at least @min_len bytes of data. If found, return a pointer to the
+ * item's data and write its actual length to @actual_len_ret if not NULL. If
+ * not found, return NULL.
+ */
+void *
+inode_get_tagged_item(const struct wim_inode *inode, u32 tag, u32 min_len,
+ u32 *actual_len_ret)
{
- size_t minlen_with_hdr = sizeof(struct tagged_item_header) + min_data_len;
- size_t len_remaining = inode->i_extra_size;
- u8 *p = inode->i_extra;
+ struct tagged_item_header *hdr;
+ size_t len_remaining;
- /* Iterate through the tagged items. */
- while (len_remaining >= minlen_with_hdr) {
- struct tagged_item_header *hdr;
- u32 tag;
- u32 len;
+ if (!inode->i_extra)
+ return NULL;
- hdr = (struct tagged_item_header *)p;
- tag = le32_to_cpu(hdr->tag);
- len = le32_to_cpu(hdr->length);
+ hdr = (struct tagged_item_header *)inode->i_extra->data;
+ len_remaining = inode->i_extra->size;
- if (tag == desired_tag && len >= min_data_len)
- return hdr->data;
+ /* Iterate through the tagged items. */
+ while (len_remaining >= sizeof(*hdr) + min_len) {
+ u32 len = le32_to_cpu(hdr->length);
+ u32 full_len = sizeof(*hdr) + ALIGN(len, 8);
- len = (len + 7) & ~7;
- if (len_remaining <= sizeof(struct tagged_item_header) + len)
+ /* Length overflow (corrupted item list)? */
+ if (unlikely(full_len < len || full_len > len_remaining))
return NULL;
- len_remaining -= sizeof(struct tagged_item_header) + len;
- p += sizeof(struct tagged_item_header) + len;
+
+ /* Matches the item we wanted? */
+ if (le32_to_cpu(hdr->tag) == tag && len >= min_len) {
+ if (actual_len_ret)
+ *actual_len_ret = len;
+ return hdr->data;
+ }
+
+ len_remaining -= full_len;
+ hdr = (struct tagged_item_header *)((u8 *)hdr + full_len);
}
return NULL;
}
-/* Adds a tagged item to a WIM inode and returns a pointer to its uninitialized
- * data, which must be initialized in-place by the caller. */
+/*
+ * Add a tagged item to the specified inode and return a pointer to its
+ * uninitialized data, which the caller must initialize. No check is made for
+ * whether the inode already has item(s) with the specified tag.
+ */
static void *
inode_add_tagged_item(struct wim_inode *inode, u32 tag, u32 len)
{
- size_t itemsize;
- size_t newsize;
- u8 *buf;
+ struct wim_inode_extra *extra;
struct tagged_item_header *hdr;
+ size_t oldsize = (inode->i_extra ? inode->i_extra->size : 0);
+ size_t newsize = oldsize + sizeof(*hdr) + ALIGN(len, 8);
- /* We prepend the item instead of appending it because it's easier. */
-
- itemsize = sizeof(struct tagged_item_header) + len;
- newsize = itemsize + inode->i_extra_size;
+ wimlib_assert(oldsize % 8 == 0);
- buf = MALLOC(newsize);
- if (!buf)
+ extra = REALLOC(inode->i_extra, sizeof(*extra) + newsize);
+ if (!extra)
return NULL;
-
- if (inode->i_extra_size) {
- memcpy(buf + itemsize, inode->i_extra, inode->i_extra_size);
- FREE(inode->i_extra);
- }
- inode->i_extra = buf;
- inode->i_extra_size = newsize;
-
- hdr = (struct tagged_item_header *)buf;
+ inode->i_extra = extra;
+ extra->size = newsize;
+ hdr = (struct tagged_item_header *)&extra->data[oldsize];
hdr->tag = cpu_to_le32(tag);
hdr->length = cpu_to_le32(len);
+ memset(hdr->data + len, 0, -len & 7); /* pad to next 8-byte boundary */
return hdr->data;
}
-static inline struct wimlib_unix_data_disk *
-inode_get_unix_data_disk(const struct wim_inode *inode)
+/*
+ * Add a tagged item containing the specified data to the specified inode, first
+ * removing any existing items with the same tag. Returns %true if successful,
+ * %false if failed (out of memory).
+ */
+bool
+inode_set_tagged_item(struct wim_inode *inode, u32 tag,
+ const void *data, u32 len)
{
- return inode_get_tagged_item(inode, TAG_WIMLIB_UNIX_DATA,
- sizeof(struct wimlib_unix_data_disk));
+ u8 *p;
+ u32 old_len;
+
+ /* Remove any existing items with the same tag */
+ while ((p = inode_get_tagged_item(inode, tag, 0, &old_len)) != NULL) {
+ p -= sizeof(struct tagged_item_header);
+ old_len += sizeof(struct tagged_item_header);
+ old_len = ALIGN(old_len, 8);
+ memmove(p, p + old_len, (inode->i_extra->data +
+ inode->i_extra->size) - (p + old_len));
+ inode->i_extra->size -= old_len;
+ }
+
+ /* Add the new item */
+ p = inode_add_tagged_item(inode, tag, len);
+ if (!p)
+ return false;
+ memcpy(p, data, len);
+ return true;
}
+struct wimlib_unix_data_disk {
+ le32 uid;
+ le32 gid;
+ le32 mode;
+ le32 rdev;
+};
+
static inline struct wimlib_unix_data_disk *
-inode_add_unix_data_disk(struct wim_inode *inode)
+inode_get_unix_data_disk(const struct wim_inode *inode)
{
- return inode_add_tagged_item(inode, TAG_WIMLIB_UNIX_DATA,
- sizeof(struct wimlib_unix_data_disk));
+ return inode_get_tagged_item(inode, TAG_WIMLIB_UNIX_DATA,
+ sizeof(struct wimlib_unix_data_disk),
+ NULL);
}
-/* Returns %true if the specified WIM inode has UNIX data; otherwise %false.
- * This is a wimlib extension. */
+/* Return %true iff the specified inode has standard UNIX metadata. */
bool
inode_has_unix_data(const struct wim_inode *inode)
{
return inode_get_unix_data_disk(inode) != NULL;
}
-/* Retrieves UNIX data from the specified WIM inode.
- * This is a wimlib extension.
+/*
+ * Get an inode's standard UNIX metadata.
*
- * Returns %true and fills @unix_data if the inode has UNIX data.
- * Otherwise returns %false. */
+ * If the inode has standard UNIX metadata, returns %true and fills @unix_data.
+ * Otherwise returns %false.
+ */
bool
inode_get_unix_data(const struct wim_inode *inode,
struct wimlib_unix_data *unix_data)
return true;
}
-/* Sets UNIX data on the specified WIM inode.
- * This is a wimlib extension.
+/*
+ * Set an inode's standard UNIX metadata.
*
* Callers must specify all members in @unix_data. If the inode does not yet
- * have UNIX data, it is given these values. Otherwise, only the values that
- * also have the corresponding flags in @which set are changed.
+ * have standard UNIX metadata, it is given these values. Otherwise, only the
+ * values that also have the corresponding flags in @which set are changed.
*
- * Returns %true if successful, %false if failed (out of memory). */
+ * Returns %true if successful, %false if failed (out of memory).
+ */
bool
inode_set_unix_data(struct wim_inode *inode, struct wimlib_unix_data *unix_data,
int which)
p = inode_get_unix_data_disk(inode);
if (!p) {
- p = inode_add_unix_data_disk(inode);
+ p = inode_add_tagged_item(inode, TAG_WIMLIB_UNIX_DATA,
+ sizeof(*p));
if (!p)
return false;
which = UNIX_DATA_ALL;
git://wimlib.net / wimlib / blobdiff