*/
/*
- * 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/lookup_table.h"
+#include "wimlib/metadata.h"
+#include "wimlib/resource.h"
+#include "wimlib/security.h"
+#include "wimlib/write.h"
/*
- * Reads the metadata metadata resource from 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
- * of its child entries from the beginning of the metadata resource. An
- * 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.
+ * Reads and parses a metadata resource for an image in the WIM file.
+ *
+ * @wim:
+ * Pointer to the WIMStruct for the WIM file.
*
- * @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.
+ * @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.
+ * Return values:
+ * WIMLIB_ERR_SUCCESS (0)
+ * WIMLIB_ERR_INVALID_METADATA_RESOURCE
+ * WIMLIB_ERR_NOMEM
+ * WIMLIB_ERR_READ
+ * WIMLIB_ERR_UNEXPECTED_END_OF_FILE
+ * WIMLIB_ERR_DECOMPRESSION
*/
-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 wim_dentry *dentry;
const struct wim_lookup_table_entry *metadata_lte;
- u64 metadata_len;
- struct hlist_head inode_list;
+ void *buf;
+ int ret;
+ struct wim_security_data *sd;
+ struct wim_dentry *root;
+ struct wim_inode *inode;
metadata_lte = imd->metadata_lte;
- metadata_len = wim_resource_size(metadata_lte);
-
- DEBUG("Reading metadata resource: length = %"PRIu64", "
- "offset = %"PRIu64"", metadata_len,
- 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. */
- if (metadata_len < 8 + WIM_DENTRY_DISK_SIZE) {
- ERROR("Expected at least %u bytes for the metadata resource",
- 8 + WIM_DENTRY_DISK_SIZE);
- return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
- }
- if (sizeof(size_t) < 8 && metadata_len > 0xffffffff) {
- ERROR("Metadata resource is too large (%"PRIu64" bytes",
- metadata_len);
- return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
- }
+ DEBUG("Reading metadata resource (size=%"PRIu64").", metadata_lte->size);
- /* Allocate memory for the uncompressed metadata resource. */
- buf = MALLOC(metadata_len);
+ /* Read the metadata resource into memory. (It may be compressed.) */
+ ret = read_full_stream_into_alloc_buf(metadata_lte, &buf);
+ if (ret)
+ return ret;
- if (!buf) {
- ERROR("Failed to allocate %"PRIu64" bytes for uncompressed "
- "metadata resource", metadata_len);
- return WIMLIB_ERR_NOMEM;
+ /* Checksum the metadata resource. */
+ if (!metadata_lte->dont_check_metadata_hash) {
+ u8 hash[SHA1_HASH_SIZE];
+
+ sha1_buffer(buf, metadata_lte->size, hash);
+ if (!hashes_equal(metadata_lte->hash, hash)) {
+ ERROR("Metadata resource is corrupted "
+ "(invalid SHA-1 message digest)!");
+ ret = WIMLIB_ERR_INVALID_METADATA_RESOURCE;
+ goto out_free_buf;
+ }
}
- /* Read the metadata resource into memory. (It may be compressed.) */
- ret = read_full_wim_resource(metadata_lte, buf, 0);
- if (ret != 0)
- goto out_free_buf;
-
- DEBUG("Finished reading metadata resource into memory.");
-
- /* The root directory entry starts after security data, aligned on an
- * 8-byte boundary within the metadata resource.
+ /* Parse the metadata resource.
*
- * The security data starts with a 4-byte integer giving its total
- * length, so if we round that up to an 8-byte boundary that gives us
- * 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. */
-
- wimlib_assert(imd->security_data == NULL);
- ret = read_security_data(buf, metadata_len, &imd->security_data);
- if (ret != 0)
+ * Notes: 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 of its child entries from the
+ * beginning of the metadata resource. An 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. */
+
+ ret = read_wim_security_data(buf, metadata_lte->size, &sd);
+ 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 wim_dentry));
- if (!dentry) {
- ERROR("Failed to allocate %zu bytes for root dentry",
- sizeof(struct wim_dentry));
- ret = WIMLIB_ERR_NOMEM;
+ ret = read_dentry_tree(buf, metadata_lte->size, sd->total_length, &root);
+ if (ret)
goto out_free_security_data;
- }
-
- ret = read_dentry(buf, metadata_len, dentry_offset, dentry);
- /* This is the root dentry, so set its parent to itself. */
- dentry->parent = dentry;
-
- if (ret == 0 && dentry->length == 0) {
- ERROR("Metadata resource cannot begin with end-of-directory entry!");
- ret = WIMLIB_ERR_INVALID_DENTRY;
- }
-
- if (ret != 0) {
- FREE(dentry);
- goto out_free_security_data;
- }
-
- inode_add_dentry(dentry, dentry->d_inode);
+ /* We have everything we need from the buffer now. */
+ FREE(buf);
+ buf = NULL;
- /* 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 and validate inodes. */
- /* 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 = dentry_tree_fix_inodes(root, &imd->inode_list);
+ 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)
- goto out_free_dentry_tree;
-
- if (!w->all_images_verified) {
- 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)
+ image_for_each_inode(inode, imd) {
+ ret = verify_inode(inode, sd);
+ if (ret)
goto out_free_dentry_tree;
}
- DEBUG("Done reading image metadata");
+ /* Success; fill in the image_metadata structure. */
+ imd->root_dentry = root;
+ imd->security_data = sd;
+ INIT_LIST_HEAD(&imd->unhashed_streams);
+ DEBUG("Done parsing metadata resource.");
+ return 0;
- imd->root_dentry = dentry;
- imd->inode_list = inode_list;
- if (imd->inode_list.first)
- imd->inode_list.first->pprev = &imd->inode_list.first;
- goto out_free_buf;
out_free_dentry_tree:
- free_dentry_tree(dentry, NULL);
+ free_dentry_tree(root, NULL);
out_free_security_data:
- free_security_data(imd->security_data);
- imd->security_data = NULL;
+ free_wim_security_data(sd);
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;
-}
-
-/* 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])
-{
- /* Set up a temporary lookup table entry to provide to
- * write_wim_resource(). */
- 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;
+ sd->total_length = (total_length + 7) & ~7;
}
-/* Write the metadata resource for the current WIM image. */
-int write_metadata_resource(WIMStruct *w)
+static int
+prepare_metadata_resource(WIMStruct *wim, int image,
+ u8 **buf_ret, size_t *len_ret)
{
u8 *buf;
u8 *p;
int ret;
u64 subdir_offset;
struct wim_dentry *root;
- struct wim_lookup_table_entry *lte;
- u64 metadata_original_size;
+ u64 len;
struct wim_security_data *sd;
+ struct wim_image_metadata *imd;
+
+ DEBUG("Preparing metadata resource for image %d", image);
+
+ ret = select_wim_image(wim, image);
+ if (ret)
+ return ret;
+
+ imd = wim->image_metadata[image - 1];
- DEBUG("Writing metadata resource for image %d (offset = %"PRIu64")",
- w->current_image, ftello(w->out_fp));
+ 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
*/
recalculate_security_data_length(sd);
subdir_offset = (((u64)sd->total_length + 7) & ~7) +
- dentry_correct_total_length(root) + 8;
+ dentry_out_total_length(root) + 8;
- /* Calculate the subdirectory offsets for the entire dentry tree. */
+ /* Calculate the subdirectory offsets for the entire dentry tree. */
calculate_subdir_offsets(root, &subdir_offset);
- /* Total length of the metadata resource (uncompressed) */
- metadata_original_size = subdir_offset;
+ /* Total length of the metadata resource (uncompressed). */
+ len = subdir_offset;
- /* Allocate a buffer to contain the uncompressed metadata resource */
- buf = MALLOC(metadata_original_size);
+ /* Allocate a buffer to contain the uncompressed metadata resource. */
+ buf = MALLOC(len);
if (!buf) {
ERROR("Failed to allocate %"PRIu64" bytes for "
- "metadata resource", metadata_original_size);
+ "metadata resource", len);
return WIMLIB_ERR_NOMEM;
}
- /* Write the security data into the resource buffer */
- p = write_security_data(sd, buf);
+ /* Write the security data into the resource buffer. */
+ p = write_wim_security_data(sd, buf);
- /* Write the dentry tree into the resource buffer */
+ /* Write the dentry tree into the resource buffer. */
p = write_dentry_tree(root, p);
/* We MUST have exactly filled the buffer; otherwise we calculated its
- * size incorrectly or wrote the data incorrectly. */
- wimlib_assert(p - buf == metadata_original_size);
+ * size incorrectly or wrote the data incorrectly. */
+ wimlib_assert(p - buf == len);
+
+ *buf_ret = buf;
+ *len_ret = len;
+ return 0;
+}
+
+int
+write_metadata_resource(WIMStruct *wim, int image, int write_resource_flags)
+{
+ int ret;
+ u8 *buf;
+ size_t len;
+ struct wim_image_metadata *imd;
- /* Get the lookup table entry for the metadata resource so we can update
- * it. */
- lte = w->image_metadata[w->current_image - 1].metadata_lte;
+ ret = prepare_metadata_resource(wim, image, &buf, &len);
+ if (ret)
+ return ret;
+
+ imd = wim->image_metadata[image - 1];
/* 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,
- wimlib_get_compression_type(w),
- <e->output_resource_entry,
- lte->hash);
- if (ret != 0)
- goto out;
-
- /* 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 */
+ * compression type, in the process updating the lookup table entry for
+ * the metadata resource. */
+ ret = write_wim_resource_from_buffer(buf, len, WIM_RESHDR_FLAG_METADATA,
+ &wim->out_fd,
+ wim->out_compression_type,
+ wim->out_chunk_size,
+ &imd->metadata_lte->out_reshdr,
+ imd->metadata_lte->hash,
+ write_resource_flags);
+
+ /* Original checksum was overridden; set a flag so it isn't used. */
+ imd->metadata_lte->dont_check_metadata_hash = 1;
+
FREE(buf);
return ret;
}