xref: /linux/fs/squashfs/squashfs_fs.h (revision de6e0b198239857943db395377dc1d2ddd6c05df)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef SQUASHFS_FS
3 #define SQUASHFS_FS
4 /*
5  * Squashfs
6  *
7  * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
8  * Phillip Lougher <phillip@squashfs.org.uk>
9  *
10  * squashfs_fs.h
11  */
12 
13 #define SQUASHFS_CACHED_FRAGMENTS	CONFIG_SQUASHFS_FRAGMENT_CACHE_SIZE
14 #define SQUASHFS_MAJOR			4
15 #define SQUASHFS_MINOR			0
16 #define SQUASHFS_START			0
17 
18 /* size of metadata (inode and directory) blocks */
19 #define SQUASHFS_METADATA_SIZE		8192
20 
21 /* default size of block device I/O */
22 #ifdef CONFIG_SQUASHFS_4K_DEVBLK_SIZE
23 #define SQUASHFS_DEVBLK_SIZE 4096
24 #else
25 #define SQUASHFS_DEVBLK_SIZE 1024
26 #endif
27 
28 #define SQUASHFS_FILE_MAX_SIZE		1048576
29 #define SQUASHFS_FILE_MAX_LOG		20
30 
31 /* Max length of filename (not 255) */
32 #define SQUASHFS_NAME_LEN		256
33 
34 /* Max value for directory header count*/
35 #define SQUASHFS_DIR_COUNT		256
36 
37 #define SQUASHFS_INVALID_FRAG		(0xffffffffU)
38 #define SQUASHFS_INVALID_XATTR		(0xffffffffU)
39 #define SQUASHFS_INVALID_BLK		(-1LL)
40 
41 /* Filesystem flags */
42 #define SQUASHFS_NOI			0
43 #define SQUASHFS_NOD			1
44 #define SQUASHFS_NOF			3
45 #define SQUASHFS_NO_FRAG		4
46 #define SQUASHFS_ALWAYS_FRAG		5
47 #define SQUASHFS_DUPLICATE		6
48 #define SQUASHFS_EXPORT			7
49 #define SQUASHFS_COMP_OPT		10
50 
51 #define SQUASHFS_BIT(flag, bit)		((flag >> bit) & 1)
52 
53 #define SQUASHFS_UNCOMPRESSED_INODES(flags)	SQUASHFS_BIT(flags, \
54 						SQUASHFS_NOI)
55 
56 #define SQUASHFS_UNCOMPRESSED_DATA(flags)	SQUASHFS_BIT(flags, \
57 						SQUASHFS_NOD)
58 
59 #define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
60 						SQUASHFS_NOF)
61 
62 #define SQUASHFS_NO_FRAGMENTS(flags)		SQUASHFS_BIT(flags, \
63 						SQUASHFS_NO_FRAG)
64 
65 #define SQUASHFS_ALWAYS_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
66 						SQUASHFS_ALWAYS_FRAG)
67 
68 #define SQUASHFS_DUPLICATES(flags)		SQUASHFS_BIT(flags, \
69 						SQUASHFS_DUPLICATE)
70 
71 #define SQUASHFS_EXPORTABLE(flags)		SQUASHFS_BIT(flags, \
72 						SQUASHFS_EXPORT)
73 
74 #define SQUASHFS_COMP_OPTS(flags)		SQUASHFS_BIT(flags, \
75 						SQUASHFS_COMP_OPT)
76 
77 /* Inode types including extended types */
78 #define SQUASHFS_DIR_TYPE		1
79 #define SQUASHFS_REG_TYPE		2
80 #define SQUASHFS_SYMLINK_TYPE		3
81 #define SQUASHFS_BLKDEV_TYPE		4
82 #define SQUASHFS_CHRDEV_TYPE		5
83 #define SQUASHFS_FIFO_TYPE		6
84 #define SQUASHFS_SOCKET_TYPE		7
85 #define SQUASHFS_LDIR_TYPE		8
86 #define SQUASHFS_LREG_TYPE		9
87 #define SQUASHFS_LSYMLINK_TYPE		10
88 #define SQUASHFS_LBLKDEV_TYPE		11
89 #define SQUASHFS_LCHRDEV_TYPE		12
90 #define SQUASHFS_LFIFO_TYPE		13
91 #define SQUASHFS_LSOCKET_TYPE		14
92 
93 /* Max type value stored in directory entry */
94 #define SQUASHFS_MAX_DIR_TYPE		7
95 
96 /* Xattr types */
97 #define SQUASHFS_XATTR_USER             0
98 #define SQUASHFS_XATTR_TRUSTED          1
99 #define SQUASHFS_XATTR_SECURITY         2
100 #define SQUASHFS_XATTR_VALUE_OOL        256
101 #define SQUASHFS_XATTR_PREFIX_MASK      0xff
102 
103 /* Flag whether block is compressed or uncompressed, bit is set if block is
104  * uncompressed */
105 #define SQUASHFS_COMPRESSED_BIT		(1 << 15)
106 
107 #define SQUASHFS_COMPRESSED_SIZE(B)	(((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
108 		(B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
109 
110 #define SQUASHFS_COMPRESSED(B)		(!((B) & SQUASHFS_COMPRESSED_BIT))
111 
112 #define SQUASHFS_COMPRESSED_BIT_BLOCK	(1 << 24)
113 
114 #define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)	((B) & \
115 						~SQUASHFS_COMPRESSED_BIT_BLOCK)
116 
117 #define SQUASHFS_COMPRESSED_BLOCK(B)	(!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
118 
119 static inline int squashfs_block_size(__le32 raw)
120 {
121 	u32 size = le32_to_cpu(raw);
122 	return (size >> 25) ? -EIO : size;
123 }
124 
125 /*
126  * Inode number ops.  Inodes consist of a compressed block number, and an
127  * uncompressed offset within that block
128  */
129 #define SQUASHFS_INODE_BLK(A)		((unsigned int) ((A) >> 16))
130 
131 #define SQUASHFS_INODE_OFFSET(A)	((unsigned int) ((A) & 0xffff))
132 
133 #define SQUASHFS_MKINODE(A, B)		((long long)(((long long) (A)\
134 					<< 16) + (B)))
135 
136 /* fragment and fragment table defines */
137 #define SQUASHFS_FRAGMENT_BYTES(A)	\
138 				((A) * sizeof(struct squashfs_fragment_entry))
139 
140 #define SQUASHFS_FRAGMENT_INDEX(A)	(SQUASHFS_FRAGMENT_BYTES(A) / \
141 					SQUASHFS_METADATA_SIZE)
142 
143 #define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)	(SQUASHFS_FRAGMENT_BYTES(A) % \
144 						SQUASHFS_METADATA_SIZE)
145 
146 #define SQUASHFS_FRAGMENT_INDEXES(A)	((SQUASHFS_FRAGMENT_BYTES(A) + \
147 					SQUASHFS_METADATA_SIZE - 1) / \
148 					SQUASHFS_METADATA_SIZE)
149 
150 #define SQUASHFS_FRAGMENT_INDEX_BYTES(A)	(SQUASHFS_FRAGMENT_INDEXES(A) *\
151 						sizeof(u64))
152 
153 /* inode lookup table defines */
154 #define SQUASHFS_LOOKUP_BYTES(A)	((A) * sizeof(u64))
155 
156 #define SQUASHFS_LOOKUP_BLOCK(A)	(SQUASHFS_LOOKUP_BYTES(A) / \
157 					SQUASHFS_METADATA_SIZE)
158 
159 #define SQUASHFS_LOOKUP_BLOCK_OFFSET(A)	(SQUASHFS_LOOKUP_BYTES(A) % \
160 					SQUASHFS_METADATA_SIZE)
161 
162 #define SQUASHFS_LOOKUP_BLOCKS(A)	((SQUASHFS_LOOKUP_BYTES(A) + \
163 					SQUASHFS_METADATA_SIZE - 1) / \
164 					SQUASHFS_METADATA_SIZE)
165 
166 #define SQUASHFS_LOOKUP_BLOCK_BYTES(A)	(SQUASHFS_LOOKUP_BLOCKS(A) *\
167 					sizeof(u64))
168 
169 /* uid/gid lookup table defines */
170 #define SQUASHFS_ID_BYTES(A)		((A) * sizeof(unsigned int))
171 
172 #define SQUASHFS_ID_BLOCK(A)		(SQUASHFS_ID_BYTES(A) / \
173 					SQUASHFS_METADATA_SIZE)
174 
175 #define SQUASHFS_ID_BLOCK_OFFSET(A)	(SQUASHFS_ID_BYTES(A) % \
176 					SQUASHFS_METADATA_SIZE)
177 
178 #define SQUASHFS_ID_BLOCKS(A)		((SQUASHFS_ID_BYTES(A) + \
179 					SQUASHFS_METADATA_SIZE - 1) / \
180 					SQUASHFS_METADATA_SIZE)
181 
182 #define SQUASHFS_ID_BLOCK_BYTES(A)	(SQUASHFS_ID_BLOCKS(A) *\
183 					sizeof(u64))
184 /* xattr id lookup table defines */
185 #define SQUASHFS_XATTR_BYTES(A)		((A) * sizeof(struct squashfs_xattr_id))
186 
187 #define SQUASHFS_XATTR_BLOCK(A)		(SQUASHFS_XATTR_BYTES(A) / \
188 					SQUASHFS_METADATA_SIZE)
189 
190 #define SQUASHFS_XATTR_BLOCK_OFFSET(A)	(SQUASHFS_XATTR_BYTES(A) % \
191 					SQUASHFS_METADATA_SIZE)
192 
193 #define SQUASHFS_XATTR_BLOCKS(A)	((SQUASHFS_XATTR_BYTES(A) + \
194 					SQUASHFS_METADATA_SIZE - 1) / \
195 					SQUASHFS_METADATA_SIZE)
196 
197 #define SQUASHFS_XATTR_BLOCK_BYTES(A)	(SQUASHFS_XATTR_BLOCKS(A) *\
198 					sizeof(u64))
199 #define SQUASHFS_XATTR_BLK(A)		((unsigned int) ((A) >> 16))
200 
201 #define SQUASHFS_XATTR_OFFSET(A)	((unsigned int) ((A) & 0xffff))
202 
203 /* cached data constants for filesystem */
204 #define SQUASHFS_CACHED_BLKS		8
205 
206 /* meta index cache */
207 #define SQUASHFS_META_INDEXES	(SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
208 #define SQUASHFS_META_ENTRIES	127
209 #define SQUASHFS_META_SLOTS	8
210 
211 struct meta_entry {
212 	u64			data_block;
213 	unsigned int		index_block;
214 	unsigned short		offset;
215 	unsigned short		pad;
216 };
217 
218 struct meta_index {
219 	unsigned int		inode_number;
220 	unsigned int		offset;
221 	unsigned short		entries;
222 	unsigned short		skip;
223 	unsigned short		locked;
224 	unsigned short		pad;
225 	struct meta_entry	meta_entry[SQUASHFS_META_ENTRIES];
226 };
227 
228 
229 /*
230  * definitions for structures on disk
231  */
232 #define ZLIB_COMPRESSION	1
233 #define LZMA_COMPRESSION	2
234 #define LZO_COMPRESSION		3
235 #define XZ_COMPRESSION		4
236 #define LZ4_COMPRESSION		5
237 #define ZSTD_COMPRESSION	6
238 
239 struct squashfs_super_block {
240 	__le32			s_magic;
241 	__le32			inodes;
242 	__le32			mkfs_time;
243 	__le32			block_size;
244 	__le32			fragments;
245 	__le16			compression;
246 	__le16			block_log;
247 	__le16			flags;
248 	__le16			no_ids;
249 	__le16			s_major;
250 	__le16			s_minor;
251 	__le64			root_inode;
252 	__le64			bytes_used;
253 	__le64			id_table_start;
254 	__le64			xattr_id_table_start;
255 	__le64			inode_table_start;
256 	__le64			directory_table_start;
257 	__le64			fragment_table_start;
258 	__le64			lookup_table_start;
259 };
260 
261 struct squashfs_dir_index {
262 	__le32			index;
263 	__le32			start_block;
264 	__le32			size;
265 	unsigned char		name[];
266 };
267 
268 struct squashfs_base_inode {
269 	__le16			inode_type;
270 	__le16			mode;
271 	__le16			uid;
272 	__le16			guid;
273 	__le32			mtime;
274 	__le32			inode_number;
275 };
276 
277 struct squashfs_ipc_inode {
278 	__le16			inode_type;
279 	__le16			mode;
280 	__le16			uid;
281 	__le16			guid;
282 	__le32			mtime;
283 	__le32			inode_number;
284 	__le32			nlink;
285 };
286 
287 struct squashfs_lipc_inode {
288 	__le16			inode_type;
289 	__le16			mode;
290 	__le16			uid;
291 	__le16			guid;
292 	__le32			mtime;
293 	__le32			inode_number;
294 	__le32			nlink;
295 	__le32			xattr;
296 };
297 
298 struct squashfs_dev_inode {
299 	__le16			inode_type;
300 	__le16			mode;
301 	__le16			uid;
302 	__le16			guid;
303 	__le32			mtime;
304 	__le32			inode_number;
305 	__le32			nlink;
306 	__le32			rdev;
307 };
308 
309 struct squashfs_ldev_inode {
310 	__le16			inode_type;
311 	__le16			mode;
312 	__le16			uid;
313 	__le16			guid;
314 	__le32			mtime;
315 	__le32			inode_number;
316 	__le32			nlink;
317 	__le32			rdev;
318 	__le32			xattr;
319 };
320 
321 struct squashfs_symlink_inode {
322 	__le16			inode_type;
323 	__le16			mode;
324 	__le16			uid;
325 	__le16			guid;
326 	__le32			mtime;
327 	__le32			inode_number;
328 	__le32			nlink;
329 	__le32			symlink_size;
330 	char			symlink[];
331 };
332 
333 struct squashfs_reg_inode {
334 	__le16			inode_type;
335 	__le16			mode;
336 	__le16			uid;
337 	__le16			guid;
338 	__le32			mtime;
339 	__le32			inode_number;
340 	__le32			start_block;
341 	__le32			fragment;
342 	__le32			offset;
343 	__le32			file_size;
344 	__le16			block_list[];
345 };
346 
347 struct squashfs_lreg_inode {
348 	__le16			inode_type;
349 	__le16			mode;
350 	__le16			uid;
351 	__le16			guid;
352 	__le32			mtime;
353 	__le32			inode_number;
354 	__le64			start_block;
355 	__le64			file_size;
356 	__le64			sparse;
357 	__le32			nlink;
358 	__le32			fragment;
359 	__le32			offset;
360 	__le32			xattr;
361 	__le16			block_list[];
362 };
363 
364 struct squashfs_dir_inode {
365 	__le16			inode_type;
366 	__le16			mode;
367 	__le16			uid;
368 	__le16			guid;
369 	__le32			mtime;
370 	__le32			inode_number;
371 	__le32			start_block;
372 	__le32			nlink;
373 	__le16			file_size;
374 	__le16			offset;
375 	__le32			parent_inode;
376 };
377 
378 struct squashfs_ldir_inode {
379 	__le16			inode_type;
380 	__le16			mode;
381 	__le16			uid;
382 	__le16			guid;
383 	__le32			mtime;
384 	__le32			inode_number;
385 	__le32			nlink;
386 	__le32			file_size;
387 	__le32			start_block;
388 	__le32			parent_inode;
389 	__le16			i_count;
390 	__le16			offset;
391 	__le32			xattr;
392 	struct squashfs_dir_index	index[];
393 };
394 
395 union squashfs_inode {
396 	struct squashfs_base_inode		base;
397 	struct squashfs_dev_inode		dev;
398 	struct squashfs_ldev_inode		ldev;
399 	struct squashfs_symlink_inode		symlink;
400 	struct squashfs_reg_inode		reg;
401 	struct squashfs_lreg_inode		lreg;
402 	struct squashfs_dir_inode		dir;
403 	struct squashfs_ldir_inode		ldir;
404 	struct squashfs_ipc_inode		ipc;
405 	struct squashfs_lipc_inode		lipc;
406 };
407 
408 struct squashfs_dir_entry {
409 	__le16			offset;
410 	__le16			inode_number;
411 	__le16			type;
412 	__le16			size;
413 	char			name[];
414 };
415 
416 struct squashfs_dir_header {
417 	__le32			count;
418 	__le32			start_block;
419 	__le32			inode_number;
420 };
421 
422 struct squashfs_fragment_entry {
423 	__le64			start_block;
424 	__le32			size;
425 	unsigned int		unused;
426 };
427 
428 struct squashfs_xattr_entry {
429 	__le16			type;
430 	__le16			size;
431 	char			data[];
432 };
433 
434 struct squashfs_xattr_val {
435 	__le32			vsize;
436 	char			value[];
437 };
438 
439 struct squashfs_xattr_id {
440 	__le64			xattr;
441 	__le32			count;
442 	__le32			size;
443 };
444 
445 struct squashfs_xattr_id_table {
446 	__le64			xattr_table_start;
447 	__le32			xattr_ids;
448 	__le32			unused;
449 };
450 
451 #endif
452