packages/squashfs-tools
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
squashfs-tools/6006-unsquash-4-get-fs-table-start-and-end-points.patch
overweight 52ce7434a4 Package init
2019-09-30 11:17:34 -04:00

181 lines
6.0 KiB
Diff
Raw Blame History

From 00c97a78471b9757271ae67807a8913049658f3a Mon Sep 17 00:00:00 2001
From: renxudong <renxudong1@huawei.com>
Date: Sun, 11 Aug 2019 01:18:34 -0400
Subject: [PATCH 6/8] unsquash-4-get-fs-table-start-and-end-points
---
squashfs-tools/read_xattrs.c | 14 +++++++++++--
squashfs-tools/unsquash-4.c | 48 ++++++++++++++++++++++++++++++++++++++------
squashfs-tools/xattr.c | 4 ++--
squashfs-tools/xattr.h | 4 ++--
4 files changed, 58 insertions(+), 12 deletions(-)
diff --git a/squashfs-tools/read_xattrs.c b/squashfs-tools/read_xattrs.c
index 42106f5..9c66387 100644
--- a/squashfs-tools/read_xattrs.c
+++ b/squashfs-tools/read_xattrs.c
@@ -2,7 +2,7 @@
* Read a squashfs filesystem. This is a highly compressed read only
* filesystem.
*
- * Copyright (c) 2010, 2012, 2013
+ * Copyright (c) 2010, 2012, 2013, 2019
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
@@ -148,7 +148,7 @@ static int read_xattr_entry(struct xattr_list *xattr,
* Read and decompress the xattr id table and the xattr metadata.
* This is cached in memory for later use by get_xattr()
*/
-int read_xattrs_from_disk(int fd, struct squashfs_super_block *sBlk)
+int read_xattrs_from_disk(int fd, struct squashfs_super_block *sBlk, int flag, long long *table_start)
{
int res, bytes, i, indexes, index_bytes, ids;
long long *index, start, end;
@@ -170,6 +170,16 @@ int read_xattrs_from_disk(int fd, struct squashfs_super_block *sBlk)
SQUASHFS_INSWAP_XATTR_TABLE(&id_table);
+ if(flag) {
+ /*
+ * id_table.xattr_table_start stores the start of the compressed xattr
+ * * metadata blocks. This by definition is also the end of the previous
+ * filesystem table - the id lookup table.
+ */
+ *table_start = id_table.xattr_table_start;
+ return id_table.xattr_ids;
+ }
+
/*
* Allocate and read the index to the xattr id table metadata
* blocks
diff --git a/squashfs-tools/unsquash-4.c b/squashfs-tools/unsquash-4.c
index c335d7c..b501871 100644
--- a/squashfs-tools/unsquash-4.c
+++ b/squashfs-tools/unsquash-4.c
@@ -361,7 +361,7 @@ corrupted:
}
-static int read_uids_guids()
+static int read_uids_guids(long long *table_start)
{
int res, i;
int bytes = SQUASHFS_ID_BYTES(sBlk.s.no_ids);
@@ -384,6 +384,14 @@ static int read_uids_guids()
}
SQUASHFS_INSWAP_ID_BLOCKS(id_index_table, indexes);
+ /*
+ * id_index_table[0] stores the start of the compressed id blocks.
+ * This by definition is also the end of the previous filesystem
+ * table - this may be the exports table if it is present, or the
+ * fragments table if it isn't.
+ */
+ *table_start = id_index_table[0];
+
for(i = 0; i < indexes; i++) {
int expected = (i + 1) != indexes ? SQUASHFS_METADATA_SIZE :
bytes & (SQUASHFS_METADATA_SIZE - 1);
@@ -402,11 +410,42 @@ static int read_uids_guids()
}
+static int parse_exports_table(long long *table_start)
+{
+ int res;
+ int indexes = SQUASHFS_LOOKUP_BLOCKS(sBlk.s.inodes);
+ long long export_index_table[indexes];
+
+ res = read_fs_bytes(fd, sBlk.s.lookup_table_start,
+ SQUASHFS_LOOKUP_BLOCK_BYTES(sBlk.s.inodes), export_index_table);
+ if(res == FALSE) {
+ ERROR("parse_exports_table: failed to read export index table\n");
+ return FALSE;
+ }
+ SQUASHFS_INSWAP_LOOKUP_BLOCKS(export_index_table, indexes);
+
+ /*
+ * export_index_table[0] stores the start of the compressed export blocks.
+ * This by definition is also the end of the previous filesystem
+ * table - the fragment table.
+ */
+ *table_start = export_index_table[0];
+
+ return TRUE;
+}
+
+
int read_filesystem_tables_4()
{
- long long directory_table_end;
+ long long directory_table_end, table_start;
+
+ if(read_xattrs_from_disk(fd, &sBlk.s, no_xattrs, &table_start) == 0)
+ return FALSE;
- if(read_uids_guids() == FALSE)
+ if(read_uids_guids(&table_start) == FALSE)
+ return FALSE;
+
+ if(parse_exports_table(&table_start) == FALSE)
return FALSE;
if(read_fragment_table(&directory_table_end) == FALSE)
@@ -423,8 +462,5 @@ int read_filesystem_tables_4()
if(no_xattrs)
sBlk.s.xattr_id_table_start = SQUASHFS_INVALID_BLK;
- if(read_xattrs_from_disk(fd, &sBlk.s) == 0)
- return FALSE;
-
return TRUE;
}
diff --git a/squashfs-tools/xattr.c b/squashfs-tools/xattr.c
index b46550c..dddba7b 100644
--- a/squashfs-tools/xattr.c
+++ b/squashfs-tools/xattr.c
@@ -85,7 +85,7 @@ extern int mangle(char *, char *, int, int, int, int);
extern char *pathname(struct dir_ent *);
/* helper functions and definitions from read_xattrs.c */
-extern int read_xattrs_from_disk(int, struct squashfs_super_block *);
+extern int read_xattrs_from_disk(int, struct squashfs_super_block *, int, long long *);
extern struct xattr_list *get_xattr(int, unsigned int *, int);
extern struct prefix prefix_table[];
@@ -635,7 +635,7 @@ int get_xattrs(int fd, struct squashfs_super_block *sBlk)
TRACE("get_xattrs\n");
- res = read_xattrs_from_disk(fd, sBlk);
+ res = read_xattrs_from_disk(fd, sBlk, FALSE, NULL);
if(res == SQUASHFS_INVALID_BLK || res == 0)
goto done;
ids = res;
diff --git a/squashfs-tools/xattr.h b/squashfs-tools/xattr.h
index 9260255..13e5519 100644
--- a/squashfs-tools/xattr.h
+++ b/squashfs-tools/xattr.h
@@ -73,7 +73,7 @@ extern void save_xattrs();
extern void restore_xattrs();
extern unsigned int xattr_bytes, total_xattr_bytes;
extern void write_xattr(char *, unsigned int);
-extern int read_xattrs_from_disk(int, struct squashfs_super_block *);
+extern int read_xattrs_from_disk(int, struct squashfs_super_block *, int, long long *);
extern struct xattr_list *get_xattr(int, unsigned int *, int);
extern void free_xattr(struct xattr_list *, int);
#else
@@ -115,7 +115,7 @@ static inline void write_xattr(char *pathname, unsigned int xattr)
}
-static inline int read_xattrs_from_disk(int fd, struct squashfs_super_block *sBlk)
+static inline int read_xattrs_from_disk(int fd, struct squashfs_super_block *sBlk, int flag, long long *table_start)
{
if(sBlk->xattr_id_table_start != SQUASHFS_INVALID_BLK) {
fprintf(stderr, "Xattrs in filesystem! These are not "
--
1.8.3.1
Reference in New Issue View Git Blame Copy Permalink