/* SPDX-License-Identifier: GPL-2.0 */ /* * Copyright (C) 2020 Bootlin * * Author: Joao Marcos Costa */ #ifndef SQFS_FILESYSTEM_H #define SQFS_FILESYSTEM_H #include #include #include #include #define SQFS_MAGIC_NUMBER 0x73717368 /* The three first members of squashfs_dir_index make a total of 12 bytes */ #define SQFS_DIR_INDEX_BASE_LENGTH 12 /* size of metadata (inode and directory) blocks */ #define SQFS_METADATA_BLOCK_SIZE 8192 /* Max. number of fragment entries in a metadata block is 512 */ #define SQFS_MAX_ENTRIES 512 /* Metadata blocks start by a 2-byte length header */ #define SQFS_HEADER_SIZE 2 #define SQFS_DIR_HEADER_SIZE 12 #define SQFS_MISC_ENTRY_TYPE -1 #define SQFS_EMPTY_FILE_SIZE 3 #define SQFS_STOP_READDIR 1 #define SQFS_EMPTY_DIR -1 /* * A directory entry object has a fixed length of 8 bytes, corresponding to its * first four members, plus the size of the entry name, which is equal to * 'entry_name' + 1 bytes. */ #define SQFS_ENTRY_BASE_LENGTH 8 /* Inode types */ #define SQFS_DIR_TYPE 1 #define SQFS_REG_TYPE 2 #define SQFS_SYMLINK_TYPE 3 #define SQFS_BLKDEV_TYPE 4 #define SQFS_CHRDEV_TYPE 5 #define SQFS_FIFO_TYPE 6 #define SQFS_SOCKET_TYPE 7 #define SQFS_LDIR_TYPE 8 #define SQFS_LREG_TYPE 9 #define SQFS_LSYMLINK_TYPE 10 #define SQFS_LBLKDEV_TYPE 11 #define SQFS_LCHRDEV_TYPE 12 #define SQFS_LFIFO_TYPE 13 #define SQFS_LSOCKET_TYPE 14 struct squashfs_super_block { __le32 s_magic; __le32 inodes; __le32 mkfs_time; __le32 block_size; __le32 fragments; __le16 compression; __le16 block_log; __le16 flags; __le16 no_ids; __le16 s_major; __le16 s_minor; __le64 root_inode; __le64 bytes_used; __le64 id_table_start; __le64 xattr_id_table_start; __le64 inode_table_start; __le64 directory_table_start; __le64 fragment_table_start; __le64 export_table_start; }; struct squashfs_ctxt { struct disk_partition cur_part_info; struct blk_desc *cur_dev; struct squashfs_super_block *sblk; #if IS_ENABLED(CONFIG_ZSTD) void *zstd_workspace; #endif }; struct squashfs_directory_index { u32 index; u32 start; u32 size; char name[0]; }; struct squashfs_base_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; }; struct squashfs_ipc_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 nlink; }; struct squashfs_lipc_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 nlink; __le32 xattr; }; struct squashfs_dev_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 nlink; __le32 rdev; }; struct squashfs_ldev_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 nlink; __le32 rdev; __le32 xattr; }; struct squashfs_symlink_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 nlink; __le32 symlink_size; char symlink[0]; }; struct squashfs_reg_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 start_block; __le32 fragment; __le32 offset; __le32 file_size; __le32 block_list[0]; }; struct squashfs_lreg_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le64 start_block; __le64 file_size; __le64 sparse; __le32 nlink; __le32 fragment; __le32 offset; __le32 xattr; __le32 block_list[0]; }; struct squashfs_dir_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 start_block; __le32 nlink; __le16 file_size; __le16 offset; __le32 parent_inode; }; struct squashfs_ldir_inode { __le16 inode_type; __le16 mode; __le16 uid; __le16 guid; __le32 mtime; __le32 inode_number; __le32 nlink; __le32 file_size; __le32 start_block; __le32 parent_inode; __le16 i_count; __le16 offset; __le32 xattr; struct squashfs_directory_index index[0]; }; union squashfs_inode { struct squashfs_base_inode *base; struct squashfs_dev_inode *dev; struct squashfs_ldev_inode *ldev; struct squashfs_symlink_inode *symlink; struct squashfs_reg_inode *reg; struct squashfs_lreg_inode *lreg; struct squashfs_dir_inode *dir; struct squashfs_ldir_inode *ldir; struct squashfs_ipc_inode *ipc; struct squashfs_lipc_inode *lipc; }; struct squashfs_directory_entry { u16 offset; s16 inode_offset; u16 type; u16 name_size; char name[0]; }; struct squashfs_directory_header { u32 count; u32 start; u32 inode_number; }; struct squashfs_fragment_block_entry { u64 start; u32 size; u32 _unused; }; struct squashfs_dir_stream { struct fs_dir_stream fs_dirs; struct fs_dirent dentp; /* * 'size' is the uncompressed size of the entire listing, including * headers. 'entry_count' is the number of entries following a * specific header. Both variables are decremented in sqfs_readdir() so * the function knows when the end of the directory is reached. */ size_t size; int entry_count; /* SquashFS structures */ struct squashfs_directory_header *dir_header; struct squashfs_directory_entry *entry; /* * 'table' points to a position into the directory table. Both 'table' * and 'inode' are defined for the first time in sqfs_opendir(). * 'table's value changes in sqfs_readdir(). */ unsigned char *table; union squashfs_inode i; struct squashfs_dir_inode i_dir; struct squashfs_ldir_inode i_ldir; /* * References to the tables' beginnings. They are assigned in * sqfs_opendir() and freed in sqfs_closedir(). */ unsigned char *inode_table; unsigned char *dir_table; }; struct squashfs_file_info { /* File size in bytes (uncompressed) */ size_t size; /* Reference to list of data blocks's sizes */ u32 *blk_sizes; /* Offset into the fragment block */ u32 offset; /* Offset in which the data blocks begin */ u64 start; /* Is file fragmented? */ bool frag; /* Compressed fragment */ bool comp; }; void *sqfs_find_inode(void *inode_table, int inode_number, __le32 inode_count, __le32 block_size); int sqfs_dir_offset(void *dir_i, u32 *m_list, int m_count); int sqfs_read_metablock(unsigned char *file_mapping, int offset, bool *compressed, u32 *data_size); bool sqfs_is_empty_dir(void *dir_i); bool sqfs_is_dir(u16 type); #endif /* SQFS_FILESYSTEM_H */