+/*
+ * verify.c
+ *
+ * Some functions to verify that stuff in the WIM is valid. Of course, not
+ * *all* the verifications of the input data are in this file.
+ */
+
+/*
+ * Copyright (C) 2012 Eric Biggers
+ *
+ * wimlib - Library for working with WIM files
+ *
+ * This file is part of wimlib, a library for working with WIM files.
+ *
+ * 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
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with wimlib; if not, see http://www.gnu.org/licenses/.
+ */
+
+#include "wimlib_internal.h"
+#include "dentry.h"
+#include "lookup_table.h"
+
+static inline struct dentry *inode_first_dentry(struct inode *inode)
+{
+ wimlib_assert(inode->dentry_list.next != &inode->dentry_list);
+ return container_of(inode->dentry_list.next, struct dentry,
+ inode_dentry_list);
+}
+
+static int verify_inode(struct inode *inode, const WIMStruct *w)
+{
+ const struct lookup_table *table = w->lookup_table;
+ const struct wim_security_data *sd = wim_const_security_data(w);
+ const struct dentry *first_dentry = inode_first_dentry(inode);
+ int ret = WIMLIB_ERR_INVALID_DENTRY;
+
+ /* Check the security ID */
+ if (inode->security_id < -1) {
+ ERROR("Dentry `%s' has an invalid security ID (%d)",
+ first_dentry->full_path_utf8, inode->security_id);
+ goto out;
+ }
+ if (inode->security_id >= sd->num_entries) {
+ ERROR("Dentry `%s' has an invalid security ID (%d) "
+ "(there are only %u entries in the security table)",
+ first_dentry->full_path_utf8, inode->security_id,
+ sd->num_entries);
+ goto out;
+ }
+
+ /* Check that lookup table entries for all the resources exist, except
+ * if the SHA1 message digest is all 0's, which indicates there is
+ * intentionally no resource there. */
+ if (w->hdr.total_parts == 1) {
+ for (unsigned i = 0; i <= inode->num_ads; i++) {
+ struct lookup_table_entry *lte;
+ const u8 *hash;
+ hash = inode_stream_hash_unresolved(inode, i);
+ lte = __lookup_resource(table, hash);
+ if (!lte && !is_zero_hash(hash)) {
+ ERROR("Could not find lookup table entry for stream "
+ "%u of dentry `%s'", i, first_dentry->full_path_utf8);
+ goto out;
+ }
+ if (lte)
+ lte->real_refcnt += inode->link_count;
+
+ /* The following is now done when required by
+ * wim_run_full_verifications(). */
+
+ #if 0
+ if (lte && !w->full_verification_in_progress &&
+ lte->real_refcnt > lte->refcnt)
+ {
+ #ifdef ENABLE_ERROR_MESSAGES
+ WARNING("The following lookup table entry "
+ "has a reference count of %u, but",
+ lte->refcnt);
+ WARNING("We found %u references to it",
+ lte->real_refcnt);
+ WARNING("(One dentry referencing it is at `%s')",
+ first_dentry->full_path_utf8);
+
+ print_lookup_table_entry(lte);
+ #endif
+ /* Guess what! install.wim for Windows 8
+ * contains many streams referenced by more
+ * dentries than the refcnt stated in the lookup
+ * table entry. So we will need to handle this
+ * case and not just make it be an error... I'm
+ * just setting the reference count to the
+ * number of references we found.
+ * (Unfortunately, even after doing this, the
+ * reference count could be too low if it's also
+ * referenced in other WIM images) */
+
+ #if 1
+ lte->refcnt = lte->real_refcnt;
+ WARNING("Fixing reference count");
+ #else
+ goto out;
+ #endif
+ }
+ #endif
+ }
+ }
+
+ /* Make sure there is only one un-named stream. */
+ unsigned num_unnamed_streams = 0;
+ for (unsigned i = 0; i <= inode->num_ads; i++) {
+ const u8 *hash;
+ hash = inode_stream_hash_unresolved(inode, i);
+ if (!inode_stream_name_len(inode, i) && !is_zero_hash(hash))
+ num_unnamed_streams++;
+ }
+ if (num_unnamed_streams > 1) {
+ ERROR("Dentry `%s' has multiple (%u) un-named streams",
+ first_dentry->full_path_utf8, num_unnamed_streams);
+ goto out;
+ }
+ inode->verified = true;
+ ret = 0;
+out:
+ return ret;
+}
+
+/* Run some miscellaneous verifications on a WIM dentry */
+int verify_dentry(struct dentry *dentry, void *wim)
+{
+ int ret;
+
+ if (!dentry->d_inode->verified) {
+ ret = verify_inode(dentry->d_inode, wim);
+ if (ret != 0)
+ return ret;
+ }
+
+ /* Cannot have a short name but no long name */
+ if (dentry->short_name_len && !dentry->file_name_len) {
+ ERROR("Dentry `%s' has a short name but no long name",
+ dentry->full_path_utf8);
+ return WIMLIB_ERR_INVALID_DENTRY;
+ }
+
+ /* Make sure root dentry is unnamed */
+ if (dentry_is_root(dentry)) {
+ if (dentry->file_name_len) {
+ ERROR("The root dentry is named `%s', but it must "
+ "be unnamed", dentry->file_name_utf8);
+ return WIMLIB_ERR_INVALID_DENTRY;
+ }
+ }
+
+#if 0
+ /* Check timestamps */
+ if (inode->last_access_time < inode->creation_time ||
+ inode->last_write_time < inode->creation_time) {
+ WARNING("Dentry `%s' was created after it was last accessed or "
+ "written to", dentry->full_path_utf8);
+ }
+#endif
+
+ return 0;
+}
+
+static int image_run_full_verifications(WIMStruct *w)
+{
+ return for_dentry_in_tree(wim_root_dentry(w), verify_dentry, w);
+}
+
+static int lte_fix_refcnt(struct lookup_table_entry *lte, void *ctr)
+{
+ if (lte->refcnt != lte->real_refcnt) {
+ WARNING("The following lookup table entry has a reference "
+ "count of %u, but", lte->refcnt);
+ WARNING("We found %u references to it",
+ lte->real_refcnt);
+ print_lookup_table_entry(lte);
+ lte->refcnt = lte->real_refcnt;
+ ++*(unsigned long *)ctr;
+ }
+ return 0;
+}
+
+/* Ideally this would be unnecessary... however, the WIMs for Windows 8 are
+ * screwed up because some lookup table entries are referenced more times than
+ * their stated reference counts. So theoretically, if we delete all the
+ * references to a stream and then remove it, it might still be referenced
+ * somewhere else, making a file be missing from the WIM... So, work around this
+ * problem by looking at ALL the images to re-calculate the reference count of
+ * EVERY lookup table entry. This only absolutely has to be done before an image
+ * is deleted or before an image is mounted read-write. */
+int wim_run_full_verifications(WIMStruct *w)
+{
+ int ret;
+
+ for_lookup_table_entry(w->lookup_table, lte_zero_real_refcnt, NULL);
+ w->all_images_verified = 1;
+ w->full_verification_in_progress = 1;
+ ret = for_image(w, WIMLIB_ALL_IMAGES, image_run_full_verifications);
+ w->full_verification_in_progress = 0;
+ if (ret == 0) {
+ unsigned long num_ltes_with_bogus_refcnt = 0;
+ for (int i = 0; i < w->hdr.image_count; i++)
+ w->image_metadata[i].metadata_lte->real_refcnt++;
+ for_lookup_table_entry(w->lookup_table, lte_fix_refcnt,
+ &num_ltes_with_bogus_refcnt);
+ if (num_ltes_with_bogus_refcnt != 0) {
+ WARNING("A total of %lu entries in the WIM's stream "
+ "lookup table had to have\n"
+ " their reference counts fixed.",
+ num_ltes_with_bogus_refcnt);
+ }
+ } else {
+ w->all_images_verified = 0;
+ }
+ return ret;
+}
+
+/*
+ * Sanity checks to make sure a set of WIMs correctly correspond to a spanned
+ * set.
+ *
+ * @w:
+ * Part 1 of the set.
+ *
+ * @additional_swms:
+ * All parts of the set other than part 1.
+ *
+ * @num_additional_swms:
+ * Number of WIMStructs in @additional_swms. Or, the total number of parts
+ * in the set minus 1.
+ *
+ * @return:
+ * 0 on success; WIMLIB_ERR_SPLIT_INVALID if the set is not valid.
+ */
+int verify_swm_set(WIMStruct *w, WIMStruct **additional_swms,
+ unsigned num_additional_swms)
+{
+ unsigned total_parts = w->hdr.total_parts;
+ int ctype;
+ const u8 *guid;
+
+ if (total_parts != num_additional_swms + 1) {
+ ERROR("`%s' says there are %u parts in the spanned set, "
+ "but %s%u part%s provided",
+ w->filename, total_parts,
+ (num_additional_swms + 1 < total_parts) ? "only " : "",
+ num_additional_swms + 1,
+ (num_additional_swms) ? "s were" : " was");
+ return WIMLIB_ERR_SPLIT_INVALID;
+ }
+ if (w->hdr.part_number != 1) {
+ ERROR("WIM `%s' is not the first part of the split WIM.",
+ w->filename);
+ return WIMLIB_ERR_SPLIT_INVALID;
+ }
+ for (unsigned i = 0; i < num_additional_swms; i++) {
+ if (additional_swms[i]->hdr.total_parts != total_parts) {
+ ERROR("WIM `%s' says there are %u parts in the spanned set, "
+ "but %u parts were provided",
+ additional_swms[i]->filename,
+ additional_swms[i]->hdr.total_parts,
+ total_parts);
+ return WIMLIB_ERR_SPLIT_INVALID;
+ }
+ }
+
+ /* keep track of ctype and guid just to make sure they are the same for
+ * all the WIMs. */
+ ctype = wimlib_get_compression_type(w);
+ guid = w->hdr.guid;
+
+ WIMStruct *parts_to_swms[num_additional_swms];
+ ZERO_ARRAY(parts_to_swms);
+ for (unsigned i = 0; i < num_additional_swms; i++) {
+
+ WIMStruct *swm = additional_swms[i];
+
+ if (wimlib_get_compression_type(swm) != ctype) {
+ ERROR("The split WIMs do not all have the same "
+ "compression type");
+ return WIMLIB_ERR_SPLIT_INVALID;
+ }
+ if (memcmp(guid, swm->hdr.guid, WIM_GID_LEN) != 0) {
+ ERROR("The split WIMs do not all have the same "
+ "GUID");
+ return WIMLIB_ERR_SPLIT_INVALID;
+ }
+ if (swm->hdr.part_number == 1) {
+ ERROR("WIMs `%s' and `%s' both are marked as the "
+ "first WIM in the spanned set",
+ w->filename, swm->filename);
+ return WIMLIB_ERR_SPLIT_INVALID;
+ }
+ if (swm->hdr.part_number == 0 ||
+ swm->hdr.part_number > total_parts)
+ {
+ ERROR("WIM `%s' says it is part %u in the spanned set, "
+ "but the part number must be in the range "
+ "[1, %u]",
+ swm->filename, swm->hdr.part_number, total_parts);
+ return WIMLIB_ERR_SPLIT_INVALID;
+ }
+ if (parts_to_swms[swm->hdr.part_number - 2])
+ {
+ ERROR("`%s' and `%s' are both marked as part %u of %u "
+ "in the spanned set",
+ parts_to_swms[swm->hdr.part_number - 2]->filename,
+ swm->filename,
+ swm->hdr.part_number,
+ total_parts);
+ return WIMLIB_ERR_SPLIT_INVALID;
+ } else {
+ parts_to_swms[swm->hdr.part_number - 2] = swm;
+ }
+ }
+ return 0;
+}
+