1 #ifndef SQUASHFS_FS
2 #define SQUASHFS_FS
3 /*
4  * Squashfs
5  *
6  * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
7  * Phillip Lougher <phillip@squashfs.org.uk>
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version 2,
12  * or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
22  *
23  * squashfs_fs.h
24  */
25 
26 #define SQUASHFS_CACHED_FRAGMENTS	CONFIG_SQUASHFS_FRAGMENT_CACHE_SIZE
27 #define SQUASHFS_MAJOR			4
28 #define SQUASHFS_MINOR			0
29 #define SQUASHFS_START			0
30 
31 /* size of metadata (inode and directory) blocks */
32 #define SQUASHFS_METADATA_SIZE		8192
33 #define SQUASHFS_BLOCK_OFFSET		2
34 
35 /* default size of block device I/O */
36 #ifdef CONFIG_SQUASHFS_4K_DEVBLK_SIZE
37 #define SQUASHFS_DEVBLK_SIZE 4096
38 #else
39 #define SQUASHFS_DEVBLK_SIZE 1024
40 #endif
41 
42 #define SQUASHFS_FILE_MAX_SIZE		1048576
43 #define SQUASHFS_FILE_MAX_LOG		20
44 
45 /* Max length of filename (not 255) */
46 #define SQUASHFS_NAME_LEN		256
47 
48 /* Max value for directory header count*/
49 #define SQUASHFS_DIR_COUNT		256
50 
51 #define SQUASHFS_INVALID_FRAG		(0xffffffffU)
52 #define SQUASHFS_INVALID_XATTR		(0xffffffffU)
53 #define SQUASHFS_INVALID_BLK		(-1LL)
54 
55 /* Filesystem flags */
56 #define SQUASHFS_NOI			0
57 #define SQUASHFS_NOD			1
58 #define SQUASHFS_NOF			3
59 #define SQUASHFS_NO_FRAG		4
60 #define SQUASHFS_ALWAYS_FRAG		5
61 #define SQUASHFS_DUPLICATE		6
62 #define SQUASHFS_EXPORT			7
63 #define SQUASHFS_COMP_OPT		10
64 
65 #define SQUASHFS_BIT(flag, bit)		((flag >> bit) & 1)
66 
67 #define SQUASHFS_UNCOMPRESSED_INODES(flags)	SQUASHFS_BIT(flags, \
68 						SQUASHFS_NOI)
69 
70 #define SQUASHFS_UNCOMPRESSED_DATA(flags)	SQUASHFS_BIT(flags, \
71 						SQUASHFS_NOD)
72 
73 #define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
74 						SQUASHFS_NOF)
75 
76 #define SQUASHFS_NO_FRAGMENTS(flags)		SQUASHFS_BIT(flags, \
77 						SQUASHFS_NO_FRAG)
78 
79 #define SQUASHFS_ALWAYS_FRAGMENTS(flags)	SQUASHFS_BIT(flags, \
80 						SQUASHFS_ALWAYS_FRAG)
81 
82 #define SQUASHFS_DUPLICATES(flags)		SQUASHFS_BIT(flags, \
83 						SQUASHFS_DUPLICATE)
84 
85 #define SQUASHFS_EXPORTABLE(flags)		SQUASHFS_BIT(flags, \
86 						SQUASHFS_EXPORT)
87 
88 #define SQUASHFS_COMP_OPTS(flags)		SQUASHFS_BIT(flags, \
89 						SQUASHFS_COMP_OPT)
90 
91 /* Inode types including extended types */
92 #define SQUASHFS_DIR_TYPE		1
93 #define SQUASHFS_REG_TYPE		2
94 #define SQUASHFS_SYMLINK_TYPE		3
95 #define SQUASHFS_BLKDEV_TYPE		4
96 #define SQUASHFS_CHRDEV_TYPE		5
97 #define SQUASHFS_FIFO_TYPE		6
98 #define SQUASHFS_SOCKET_TYPE		7
99 #define SQUASHFS_LDIR_TYPE		8
100 #define SQUASHFS_LREG_TYPE		9
101 #define SQUASHFS_LSYMLINK_TYPE		10
102 #define SQUASHFS_LBLKDEV_TYPE		11
103 #define SQUASHFS_LCHRDEV_TYPE		12
104 #define SQUASHFS_LFIFO_TYPE		13
105 #define SQUASHFS_LSOCKET_TYPE		14
106 
107 /* Max type value stored in directory entry */
108 #define SQUASHFS_MAX_DIR_TYPE		7
109 
110 /* Xattr types */
111 #define SQUASHFS_XATTR_USER             0
112 #define SQUASHFS_XATTR_TRUSTED          1
113 #define SQUASHFS_XATTR_SECURITY         2
114 #define SQUASHFS_XATTR_VALUE_OOL        256
115 #define SQUASHFS_XATTR_PREFIX_MASK      0xff
116 
117 /* Flag whether block is compressed or uncompressed, bit is set if block is
118  * uncompressed */
119 #define SQUASHFS_COMPRESSED_BIT		(1 << 15)
120 
121 #define SQUASHFS_COMPRESSED_SIZE(B)	(((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
122 		(B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
123 
124 #define SQUASHFS_COMPRESSED(B)		(!((B) & SQUASHFS_COMPRESSED_BIT))
125 
126 #define SQUASHFS_COMPRESSED_BIT_BLOCK	(1 << 24)
127 
128 #define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)	((B) & \
129 						~SQUASHFS_COMPRESSED_BIT_BLOCK)
130 
131 #define SQUASHFS_COMPRESSED_BLOCK(B)	(!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
132 
squashfs_block_size(__le32 raw)133 static inline int squashfs_block_size(__le32 raw)
134 {
135 	u32 size = le32_to_cpu(raw);
136 	return (size >> 25) ? -EIO : size;
137 }
138 
139 /*
140  * Inode number ops.  Inodes consist of a compressed block number, and an
141  * uncompressed offset within that block
142  */
143 #define SQUASHFS_INODE_BLK(A)		((unsigned int) ((A) >> 16))
144 
145 #define SQUASHFS_INODE_OFFSET(A)	((unsigned int) ((A) & 0xffff))
146 
147 #define SQUASHFS_MKINODE(A, B)		((long long)(((long long) (A)\
148 					<< 16) + (B)))
149 
150 /* fragment and fragment table defines */
151 #define SQUASHFS_FRAGMENT_BYTES(A)	\
152 				((A) * sizeof(struct squashfs_fragment_entry))
153 
154 #define SQUASHFS_FRAGMENT_INDEX(A)	(SQUASHFS_FRAGMENT_BYTES(A) / \
155 					SQUASHFS_METADATA_SIZE)
156 
157 #define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)	(SQUASHFS_FRAGMENT_BYTES(A) % \
158 						SQUASHFS_METADATA_SIZE)
159 
160 #define SQUASHFS_FRAGMENT_INDEXES(A)	((SQUASHFS_FRAGMENT_BYTES(A) + \
161 					SQUASHFS_METADATA_SIZE - 1) / \
162 					SQUASHFS_METADATA_SIZE)
163 
164 #define SQUASHFS_FRAGMENT_INDEX_BYTES(A)	(SQUASHFS_FRAGMENT_INDEXES(A) *\
165 						sizeof(u64))
166 
167 /* inode lookup table defines */
168 #define SQUASHFS_LOOKUP_BYTES(A)	((A) * sizeof(u64))
169 
170 #define SQUASHFS_LOOKUP_BLOCK(A)	(SQUASHFS_LOOKUP_BYTES(A) / \
171 					SQUASHFS_METADATA_SIZE)
172 
173 #define SQUASHFS_LOOKUP_BLOCK_OFFSET(A)	(SQUASHFS_LOOKUP_BYTES(A) % \
174 					SQUASHFS_METADATA_SIZE)
175 
176 #define SQUASHFS_LOOKUP_BLOCKS(A)	((SQUASHFS_LOOKUP_BYTES(A) + \
177 					SQUASHFS_METADATA_SIZE - 1) / \
178 					SQUASHFS_METADATA_SIZE)
179 
180 #define SQUASHFS_LOOKUP_BLOCK_BYTES(A)	(SQUASHFS_LOOKUP_BLOCKS(A) *\
181 					sizeof(u64))
182 
183 /* uid/gid lookup table defines */
184 #define SQUASHFS_ID_BYTES(A)		((A) * sizeof(unsigned int))
185 
186 #define SQUASHFS_ID_BLOCK(A)		(SQUASHFS_ID_BYTES(A) / \
187 					SQUASHFS_METADATA_SIZE)
188 
189 #define SQUASHFS_ID_BLOCK_OFFSET(A)	(SQUASHFS_ID_BYTES(A) % \
190 					SQUASHFS_METADATA_SIZE)
191 
192 #define SQUASHFS_ID_BLOCKS(A)		((SQUASHFS_ID_BYTES(A) + \
193 					SQUASHFS_METADATA_SIZE - 1) / \
194 					SQUASHFS_METADATA_SIZE)
195 
196 #define SQUASHFS_ID_BLOCK_BYTES(A)	(SQUASHFS_ID_BLOCKS(A) *\
197 					sizeof(u64))
198 /* xattr id lookup table defines */
199 #define SQUASHFS_XATTR_BYTES(A)		(((u64) (A)) * sizeof(struct squashfs_xattr_id))
200 
201 #define SQUASHFS_XATTR_BLOCK(A)		(SQUASHFS_XATTR_BYTES(A) / \
202 					SQUASHFS_METADATA_SIZE)
203 
204 #define SQUASHFS_XATTR_BLOCK_OFFSET(A)	(SQUASHFS_XATTR_BYTES(A) % \
205 					SQUASHFS_METADATA_SIZE)
206 
207 #define SQUASHFS_XATTR_BLOCKS(A)	((SQUASHFS_XATTR_BYTES(A) + \
208 					SQUASHFS_METADATA_SIZE - 1) / \
209 					SQUASHFS_METADATA_SIZE)
210 
211 #define SQUASHFS_XATTR_BLOCK_BYTES(A)	(SQUASHFS_XATTR_BLOCKS(A) *\
212 					sizeof(u64))
213 #define SQUASHFS_XATTR_BLK(A)		((unsigned int) ((A) >> 16))
214 
215 #define SQUASHFS_XATTR_OFFSET(A)	((unsigned int) ((A) & 0xffff))
216 
217 /* cached data constants for filesystem */
218 #define SQUASHFS_CACHED_BLKS		8
219 
220 /* meta index cache */
221 #define SQUASHFS_META_INDEXES	(SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
222 #define SQUASHFS_META_ENTRIES	127
223 #define SQUASHFS_META_SLOTS	8
224 
225 struct meta_entry {
226 	u64			data_block;
227 	unsigned int		index_block;
228 	unsigned short		offset;
229 	unsigned short		pad;
230 };
231 
232 struct meta_index {
233 	unsigned int		inode_number;
234 	unsigned int		offset;
235 	unsigned short		entries;
236 	unsigned short		skip;
237 	unsigned short		locked;
238 	unsigned short		pad;
239 	struct meta_entry	meta_entry[SQUASHFS_META_ENTRIES];
240 };
241 
242 
243 /*
244  * definitions for structures on disk
245  */
246 #define ZLIB_COMPRESSION	1
247 #define LZMA_COMPRESSION	2
248 #define LZO_COMPRESSION		3
249 #define XZ_COMPRESSION		4
250 #define LZ4_COMPRESSION		5
251 #define ZSTD_COMPRESSION	6
252 
253 struct squashfs_super_block {
254 	__le32			s_magic;
255 	__le32			inodes;
256 	__le32			mkfs_time;
257 	__le32			block_size;
258 	__le32			fragments;
259 	__le16			compression;
260 	__le16			block_log;
261 	__le16			flags;
262 	__le16			no_ids;
263 	__le16			s_major;
264 	__le16			s_minor;
265 	__le64			root_inode;
266 	__le64			bytes_used;
267 	__le64			id_table_start;
268 	__le64			xattr_id_table_start;
269 	__le64			inode_table_start;
270 	__le64			directory_table_start;
271 	__le64			fragment_table_start;
272 	__le64			lookup_table_start;
273 };
274 
275 struct squashfs_dir_index {
276 	__le32			index;
277 	__le32			start_block;
278 	__le32			size;
279 	unsigned char		name[0];
280 };
281 
282 struct squashfs_base_inode {
283 	__le16			inode_type;
284 	__le16			mode;
285 	__le16			uid;
286 	__le16			guid;
287 	__le32			mtime;
288 	__le32			inode_number;
289 };
290 
291 struct squashfs_ipc_inode {
292 	__le16			inode_type;
293 	__le16			mode;
294 	__le16			uid;
295 	__le16			guid;
296 	__le32			mtime;
297 	__le32			inode_number;
298 	__le32			nlink;
299 };
300 
301 struct squashfs_lipc_inode {
302 	__le16			inode_type;
303 	__le16			mode;
304 	__le16			uid;
305 	__le16			guid;
306 	__le32			mtime;
307 	__le32			inode_number;
308 	__le32			nlink;
309 	__le32			xattr;
310 };
311 
312 struct squashfs_dev_inode {
313 	__le16			inode_type;
314 	__le16			mode;
315 	__le16			uid;
316 	__le16			guid;
317 	__le32			mtime;
318 	__le32			inode_number;
319 	__le32			nlink;
320 	__le32			rdev;
321 };
322 
323 struct squashfs_ldev_inode {
324 	__le16			inode_type;
325 	__le16			mode;
326 	__le16			uid;
327 	__le16			guid;
328 	__le32			mtime;
329 	__le32			inode_number;
330 	__le32			nlink;
331 	__le32			rdev;
332 	__le32			xattr;
333 };
334 
335 struct squashfs_symlink_inode {
336 	__le16			inode_type;
337 	__le16			mode;
338 	__le16			uid;
339 	__le16			guid;
340 	__le32			mtime;
341 	__le32			inode_number;
342 	__le32			nlink;
343 	__le32			symlink_size;
344 	char			symlink[0];
345 };
346 
347 struct squashfs_reg_inode {
348 	__le16			inode_type;
349 	__le16			mode;
350 	__le16			uid;
351 	__le16			guid;
352 	__le32			mtime;
353 	__le32			inode_number;
354 	__le32			start_block;
355 	__le32			fragment;
356 	__le32			offset;
357 	__le32			file_size;
358 	__le16			block_list[0];
359 };
360 
361 struct squashfs_lreg_inode {
362 	__le16			inode_type;
363 	__le16			mode;
364 	__le16			uid;
365 	__le16			guid;
366 	__le32			mtime;
367 	__le32			inode_number;
368 	__le64			start_block;
369 	__le64			file_size;
370 	__le64			sparse;
371 	__le32			nlink;
372 	__le32			fragment;
373 	__le32			offset;
374 	__le32			xattr;
375 	__le16			block_list[0];
376 };
377 
378 struct squashfs_dir_inode {
379 	__le16			inode_type;
380 	__le16			mode;
381 	__le16			uid;
382 	__le16			guid;
383 	__le32			mtime;
384 	__le32			inode_number;
385 	__le32			start_block;
386 	__le32			nlink;
387 	__le16			file_size;
388 	__le16			offset;
389 	__le32			parent_inode;
390 };
391 
392 struct squashfs_ldir_inode {
393 	__le16			inode_type;
394 	__le16			mode;
395 	__le16			uid;
396 	__le16			guid;
397 	__le32			mtime;
398 	__le32			inode_number;
399 	__le32			nlink;
400 	__le32			file_size;
401 	__le32			start_block;
402 	__le32			parent_inode;
403 	__le16			i_count;
404 	__le16			offset;
405 	__le32			xattr;
406 	struct squashfs_dir_index	index[0];
407 };
408 
409 union squashfs_inode {
410 	struct squashfs_base_inode		base;
411 	struct squashfs_dev_inode		dev;
412 	struct squashfs_ldev_inode		ldev;
413 	struct squashfs_symlink_inode		symlink;
414 	struct squashfs_reg_inode		reg;
415 	struct squashfs_lreg_inode		lreg;
416 	struct squashfs_dir_inode		dir;
417 	struct squashfs_ldir_inode		ldir;
418 	struct squashfs_ipc_inode		ipc;
419 	struct squashfs_lipc_inode		lipc;
420 };
421 
422 struct squashfs_dir_entry {
423 	__le16			offset;
424 	__le16			inode_number;
425 	__le16			type;
426 	__le16			size;
427 	char			name[0];
428 };
429 
430 struct squashfs_dir_header {
431 	__le32			count;
432 	__le32			start_block;
433 	__le32			inode_number;
434 };
435 
436 struct squashfs_fragment_entry {
437 	__le64			start_block;
438 	__le32			size;
439 	unsigned int		unused;
440 };
441 
442 struct squashfs_xattr_entry {
443 	__le16			type;
444 	__le16			size;
445 	char			data[0];
446 };
447 
448 struct squashfs_xattr_val {
449 	__le32			vsize;
450 	char			value[0];
451 };
452 
453 struct squashfs_xattr_id {
454 	__le64			xattr;
455 	__le32			count;
456 	__le32			size;
457 };
458 
459 struct squashfs_xattr_id_table {
460 	__le64			xattr_table_start;
461 	__le32			xattr_ids;
462 	__le32			unused;
463 };
464 
465 #endif
466