*/
/*
- * Copyright (C) 2012 Eric Biggers
+ * Copyright (C) 2012, 2013 Eric Biggers
*
* This file is part of wimlib, a library for working with WIM files.
*
* wimlib; if not, see http://www.gnu.org/licenses/.
*/
-#include "wimlib_internal.h"
-#include "dentry.h"
-#include "lookup_table.h"
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include "wimlib/dentry.h"
+#include "wimlib/error.h"
+#include "wimlib/file_io.h"
+#include "wimlib/lookup_table.h"
+#include "wimlib/metadata.h"
+#include "wimlib/resource.h"
+#include "wimlib/security.h"
/*
- * Reads the metadata metadata resource from the WIM file. The metadata
+ * Reads a metadata resource for an image in the WIM file. The metadata
* resource consists of the security data, followed by the directory entry for
* the root directory, followed by all the other directory entries in the
* filesystem. The subdir_offset field of each directory entry gives the start
* end-of-directory is signaled by a directory entry of length '0', really of
* length 8, because that's how long the 'length' field is.
*
- * @fp: The FILE* for the input WIM file.
- * @wim_ctype: The compression type of the WIM file.
- * @imd: Pointer to the image metadata structure. Its `metadata_lte'
- * member specifies the lookup table entry for the metadata
- * resource. The rest of the image metadata entry will be filled
- * in by this function.
+ * @w: Pointer to the WIMStruct for the WIM file.
+ *
+ * @imd: Pointer to the image metadata structure for the image whose
+ * metadata resource we are reading. Its `metadata_lte' member
+ * specifies the lookup table entry for the metadata resource. The
+ * rest of the image metadata entry will be filled in by this
+ * function.
*
- * @return: Zero on success, nonzero on failure.
+ * Returns: Zero on success, nonzero on failure.
*/
-int read_metadata_resource(WIMStruct *w, struct image_metadata *imd)
+int
+read_metadata_resource(WIMStruct *wim, struct wim_image_metadata *imd)
{
u8 *buf;
- u32 dentry_offset;
int ret;
- struct dentry *dentry;
- const struct lookup_table_entry *metadata_lte;
+ struct wim_dentry *root;
+ const struct wim_lookup_table_entry *metadata_lte;
u64 metadata_len;
- struct hlist_head inode_list;
+ u8 hash[SHA1_HASH_SIZE];
metadata_lte = imd->metadata_lte;
metadata_len = wim_resource_size(metadata_lte);
- DEBUG("Reading metadata resource: length = %"PRIu64", "
- "offset = %"PRIu64"", metadata_len,
+ DEBUG("Reading metadata resource: original_size = %"PRIu64", "
+ "size = %"PRIu64", offset = %"PRIu64"",
+ metadata_lte->resource_entry.original_size,
+ metadata_lte->resource_entry.size,
metadata_lte->resource_entry.offset);
/* There is no way the metadata resource could possibly be less than (8
* + WIM_DENTRY_DISK_SIZE) bytes, where the 8 is for security data (with
* no security descriptors) and WIM_DENTRY_DISK_SIZE is for the root
- * dentry. */
+ * entry. */
if (metadata_len < 8 + WIM_DENTRY_DISK_SIZE) {
ERROR("Expected at least %u bytes for the metadata resource",
8 + WIM_DENTRY_DISK_SIZE);
}
/* Read the metadata resource into memory. (It may be compressed.) */
- ret = read_full_wim_resource(metadata_lte, buf, 0);
- if (ret != 0)
+ ret = read_full_resource_into_buf(metadata_lte, buf);
+ if (ret)
goto out_free_buf;
+ sha1_buffer(buf, metadata_len, hash);
+ if (!hashes_equal(metadata_lte->hash, hash)) {
+ ERROR("Metadata resource is corrupted (invalid SHA-1 message digest)!");
+ ret = WIMLIB_ERR_INVALID_RESOURCE_HASH;
+ goto out_free_buf;
+ }
+
DEBUG("Finished reading metadata resource into memory.");
/* The root directory entry starts after security data, aligned on an
* the offset of the root dentry.
*
* Here we read the security data into a wim_security_data structure,
- * and if successful, go ahead and calculate the offset in the metadata
- * resource of the root dentry. */
+ * which takes case of rouding total_length. If successful, go ahead
+ * and calculate the offset in the metadata resource of the root dentry.
+ * */
- wimlib_assert(imd->security_data == NULL);
- ret = read_security_data(buf, metadata_len, &imd->security_data);
- if (ret != 0)
+ ret = read_wim_security_data(buf, metadata_len, &imd->security_data);
+ if (ret)
goto out_free_buf;
- dentry_offset = (imd->security_data->total_length + 7) & ~7;
-
- if (dentry_offset == 0) {
- ERROR("Integer overflow while reading metadata resource");
- ret = WIMLIB_ERR_INVALID_SECURITY_DATA;
- goto out_free_security_data;
- }
-
DEBUG("Reading root dentry");
/* Allocate memory for the root dentry and read it into memory */
- dentry = MALLOC(sizeof(struct dentry));
- if (!dentry) {
- ERROR("Failed to allocate %zu bytes for root dentry",
- sizeof(struct dentry));
+ root = MALLOC(sizeof(struct wim_dentry));
+ if (!root) {
ret = WIMLIB_ERR_NOMEM;
goto out_free_security_data;
}
- ret = read_dentry(buf, metadata_len, dentry_offset, dentry);
+ ret = read_dentry(buf, metadata_len,
+ imd->security_data->total_length, root);
- /* This is the root dentry, so set its parent to itself. */
- dentry->parent = dentry;
-
- if (ret == 0 && dentry->length == 0) {
+ if (ret == 0 && root->length == 0) {
ERROR("Metadata resource cannot begin with end-of-directory entry!");
ret = WIMLIB_ERR_INVALID_DENTRY;
}
- if (ret != 0) {
- FREE(dentry);
+ if (ret) {
+ FREE(root);
goto out_free_security_data;
}
- inode_add_dentry(dentry, dentry->d_inode);
+ /* This is the root dentry, so set its parent to itself. */
+ root->parent = root;
+
+ inode_add_dentry(root, root->d_inode);
/* Now read the entire directory entry tree into memory. */
DEBUG("Reading dentry tree");
- ret = read_dentry_tree(buf, metadata_len, dentry);
- if (ret != 0)
- goto out_free_dentry_tree;
-
- /* Calculate the full paths in the dentry tree. */
- DEBUG("Calculating dentry full paths");
- ret = for_dentry_in_tree(dentry, calculate_dentry_full_path, NULL);
- if (ret != 0)
+ ret = read_dentry_tree(buf, metadata_len, root);
+ if (ret)
goto out_free_dentry_tree;
/* Build hash table that maps hard link group IDs to dentry sets */
- ret = dentry_tree_fix_inodes(dentry, &inode_list);
- if (ret != 0)
+ ret = dentry_tree_fix_inodes(root, &imd->inode_list);
+ if (ret)
goto out_free_dentry_tree;
- if (!w->all_images_verified) {
+ if (!wim->all_images_verified) {
+ /* Note: verify_dentry() expects to access imd->security_data,
+ * so it needs to be set before here. */
DEBUG("Running miscellaneous verifications on the dentry tree");
- for_lookup_table_entry(w->lookup_table, lte_zero_real_refcnt, NULL);
- ret = for_dentry_in_tree(dentry, verify_dentry, w);
- if (ret != 0)
+ for_lookup_table_entry(wim->lookup_table, lte_zero_real_refcnt, NULL);
+ ret = for_dentry_in_tree(root, verify_dentry, wim);
+ if (ret)
goto out_free_dentry_tree;
}
DEBUG("Done reading image metadata");
- imd->root_dentry = dentry;
- imd->inode_list = inode_list;
- if (imd->inode_list.first)
- imd->inode_list.first->pprev = &imd->inode_list.first;
+ imd->root_dentry = root;
+ INIT_LIST_HEAD(&imd->unhashed_streams);
goto out_free_buf;
out_free_dentry_tree:
- free_dentry_tree(dentry, NULL);
+ free_dentry_tree(root, wim->lookup_table);
out_free_security_data:
- free_security_data(imd->security_data);
+ free_wim_security_data(imd->security_data);
imd->security_data = NULL;
out_free_buf:
FREE(buf);
return ret;
}
-static void recalculate_security_data_length(struct wim_security_data *sd)
+static void
+recalculate_security_data_length(struct wim_security_data *sd)
{
u32 total_length = sizeof(u64) * sd->num_entries + 2 * sizeof(u32);
for (u32 i = 0; i < sd->num_entries; i++)
total_length += sd->sizes[i];
- sd->total_length = total_length;
+ sd->total_length = (total_length + 7) & ~7;
}
/* Like write_wim_resource(), but the resource is specified by a buffer of
* uncompressed data rather a lookup table entry; also writes the SHA1 hash of
* the buffer to @hash. */
-static int write_wim_resource_from_buffer(const u8 *buf, u64 buf_size,
- FILE *out_fp, int out_ctype,
- struct resource_entry *out_res_entry,
- u8 hash[SHA1_HASH_SIZE])
+static int
+write_wim_resource_from_buffer(const void *buf, size_t buf_size,
+ int out_fd, int out_ctype,
+ struct resource_entry *out_res_entry,
+ u8 hash[SHA1_HASH_SIZE])
{
/* Set up a temporary lookup table entry to provide to
* write_wim_resource(). */
- struct lookup_table_entry lte;
+ struct wim_lookup_table_entry lte;
int ret;
- lte.resource_entry.flags = 0;
- lte.resource_entry.original_size = buf_size;
- lte.resource_entry.size = buf_size;
- lte.resource_entry.offset = 0;
lte.resource_location = RESOURCE_IN_ATTACHED_BUFFER;
- lte.attached_buffer = (u8*)buf;
-
- zero_out_hash(lte.hash);
- ret = write_wim_resource(<e, out_fp, out_ctype, out_res_entry, 0);
- if (ret != 0)
- return ret;
- copy_hash(hash, lte.hash);
- return 0;
+ lte.attached_buffer = (void*)buf;
+ lte.resource_entry.original_size = buf_size;
+ lte.resource_entry.flags = 0;
+ lte.unhashed = 1;
+ ret = write_wim_resource(<e, out_fd, out_ctype, out_res_entry, 0);
+ if (ret == 0)
+ copy_hash(hash, lte.hash);
+ return ret;
}
/* Write the metadata resource for the current WIM image. */
-int write_metadata_resource(WIMStruct *w)
+int
+write_metadata_resource(WIMStruct *w)
{
u8 *buf;
u8 *p;
int ret;
u64 subdir_offset;
- struct dentry *root;
- struct lookup_table_entry *lte;
+ struct wim_dentry *root;
+ struct wim_lookup_table_entry *lte;
u64 metadata_original_size;
struct wim_security_data *sd;
+ struct wim_image_metadata *imd;
+
+ wimlib_assert(w->out_fd != -1);
+ wimlib_assert(w->current_image != WIMLIB_NO_IMAGE);
DEBUG("Writing metadata resource for image %d (offset = %"PRIu64")",
- w->current_image, ftello(w->out_fp));
+ w->current_image, filedes_offset(w->out_fd));
+
+ imd = w->image_metadata[w->current_image - 1];
+
+ root = imd->root_dentry;
+ sd = imd->security_data;
- root = wim_root_dentry(w);
- sd = wim_security_data(w);
+ if (!root) {
+ /* Empty image; create a dummy root. */
+ ret = new_filler_directory(T(""), &root);
+ if (ret)
+ return ret;
+ imd->root_dentry = root;
+ }
/* Offset of first child of the root dentry. It's equal to:
* - The total length of the security data, rounded to the next 8-byte
}
/* Write the security data into the resource buffer */
- p = write_security_data(sd, buf);
+ p = write_wim_security_data(sd, buf);
/* Write the dentry tree into the resource buffer */
p = write_dentry_tree(root, p);
/* Get the lookup table entry for the metadata resource so we can update
* it. */
- lte = w->image_metadata[w->current_image - 1].metadata_lte;
+ lte = wim_get_current_image_metadata(w)->metadata_lte;
/* Write the metadata resource to the output WIM using the proper
* compression type. The lookup table entry for the metadata resource
* is updated. */
ret = write_wim_resource_from_buffer(buf, metadata_original_size,
- w->out_fp,
+ w->out_fd,
wimlib_get_compression_type(w),
<e->output_resource_entry,
lte->hash);
- if (ret != 0)
- goto out;
+ /* Note that although the SHA1 message digest of the metadata resource
+ * is very likely to have changed, the corresponding lookup table entry
+ * is not actually located in the hash table, so it need not be
+ * re-inserted in the hash table. */
- /* It's very likely the SHA1 message digest of the metadata resource
- * changed, so re-insert the lookup table entry into the lookup table.
- *
- * We do not check for other lookup table entries having the same SHA1
- * message digest. It's possible for 2 absolutely identical images to
- * be added, therefore causing 2 identical metadata resources to be in
- * the WIM. However, in this case, it's expected for 2 separate lookup
- * table entries to be created, even though this doesn't make a whole
- * lot of sense since they will share the same SHA1 message digest.
- * */
- lookup_table_unlink(w->lookup_table, lte);
- lookup_table_insert(w->lookup_table, lte);
- lte->out_refcnt = 1;
-
- /* Make sure that the lookup table entry for this metadata resource is
- * marked with the metadata flag. */
- lte->output_resource_entry.flags |= WIM_RESHDR_FLAG_METADATA;
-out:
/* All the data has been written to the new WIM; no need for the buffer
* anymore */
FREE(buf);
git://wimlib.net / wimlib / blobdiff