1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * This file is part of UBIFS.
4 *
5 * Copyright (C) 2006-2008 Nokia Corporation.
6 *
7 * Authors: Artem Bityutskiy (Битюцкий Артём)
8 * Adrian Hunter
9 */
10
11 /*
12 * This file describes UBIFS on-flash format and contains definitions of all the
13 * relevant data structures and constants.
14 *
15 * All UBIFS on-flash objects are stored in the form of nodes. All nodes start
16 * with the UBIFS node magic number and have the same common header. Nodes
17 * always sit at 8-byte aligned positions on the media and node header sizes are
18 * also 8-byte aligned (except for the indexing node and the padding node).
19 */
20
21 #ifndef __UBIFS_MEDIA_H__
22 #define __UBIFS_MEDIA_H__
23
24 /* UBIFS node magic number (must not have the padding byte first or last) */
25 #define UBIFS_NODE_MAGIC 0x06101831
26
27 /*
28 * UBIFS on-flash format version. This version is increased when the on-flash
29 * format is changing. If this happens, UBIFS is will support older versions as
30 * well. But older UBIFS code will not support newer formats. Format changes
31 * will be rare and only when absolutely necessary, e.g. to fix a bug or to add
32 * a new feature.
33 *
34 * UBIFS went into mainline kernel with format version 4. The older formats
35 * were development formats.
36 */
37 #define UBIFS_FORMAT_VERSION 5
38
39 /*
40 * Read-only compatibility version. If the UBIFS format is changed, older UBIFS
41 * implementations will not be able to mount newer formats in read-write mode.
42 * However, depending on the change, it may be possible to mount newer formats
43 * in R/O mode. This is indicated by the R/O compatibility version which is
44 * stored in the super-block.
45 *
46 * This is needed to support boot-loaders which only need R/O mounting. With
47 * this flag it is possible to do UBIFS format changes without a need to update
48 * boot-loaders.
49 */
50 #define UBIFS_RO_COMPAT_VERSION 0
51
52 /* Minimum logical eraseblock size in bytes */
53 #define UBIFS_MIN_LEB_SZ (15*1024)
54
55 /* Initial CRC32 value used when calculating CRC checksums */
56 #define UBIFS_CRC32_INIT 0xFFFFFFFFU
57
58 /*
59 * UBIFS does not try to compress data if its length is less than the below
60 * constant.
61 */
62 #define UBIFS_MIN_COMPR_LEN 128
63
64 /*
65 * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes
66 * shorter than uncompressed data length, UBIFS prefers to leave this data
67 * node uncompress, because it'll be read faster.
68 */
69 #define UBIFS_MIN_COMPRESS_DIFF 64
70
71 /* Root inode number */
72 #define UBIFS_ROOT_INO 1
73
74 /* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */
75 #define UBIFS_FIRST_INO 64
76
77 /*
78 * Maximum file name and extended attribute length (must be a multiple of 8,
79 * minus 1).
80 */
81 #define UBIFS_MAX_NLEN 255
82
83 /* Maximum number of data journal heads */
84 #define UBIFS_MAX_JHEADS 1
85
86 /*
87 * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system,
88 * which means that it does not treat the underlying media as consisting of
89 * blocks like in case of hard drives. Do not be confused. UBIFS block is just
90 * the maximum amount of data which one data node can have or which can be
91 * attached to an inode node.
92 */
93 #define UBIFS_BLOCK_SIZE 4096
94 #define UBIFS_BLOCK_SHIFT 12
95
96 /* UBIFS padding byte pattern (must not be first or last byte of node magic) */
97 #define UBIFS_PADDING_BYTE 0xCE
98
99 /* Maximum possible key length */
100 #define UBIFS_MAX_KEY_LEN 16
101
102 /* Key length ("simple" format) */
103 #define UBIFS_SK_LEN 8
104
105 /* Minimum index tree fanout */
106 #define UBIFS_MIN_FANOUT 3
107
108 /* Maximum number of levels in UBIFS indexing B-tree */
109 #define UBIFS_MAX_LEVELS 512
110
111 /* Maximum amount of data attached to an inode in bytes */
112 #define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE
113
114 /* LEB Properties Tree fanout (must be power of 2) and fanout shift */
115 #define UBIFS_LPT_FANOUT 4
116 #define UBIFS_LPT_FANOUT_SHIFT 2
117
118 /* LEB Properties Tree bit field sizes */
119 #define UBIFS_LPT_CRC_BITS 16
120 #define UBIFS_LPT_CRC_BYTES 2
121 #define UBIFS_LPT_TYPE_BITS 4
122
123 /* The key is always at the same position in all keyed nodes */
124 #define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key)
125
126 /* Garbage collector journal head number */
127 #define UBIFS_GC_HEAD 0
128 /* Base journal head number */
129 #define UBIFS_BASE_HEAD 1
130 /* Data journal head number */
131 #define UBIFS_DATA_HEAD 2
132
133 /*
134 * LEB Properties Tree node types.
135 *
136 * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties)
137 * UBIFS_LPT_NNODE: LPT internal node
138 * UBIFS_LPT_LTAB: LPT's own lprops table
139 * UBIFS_LPT_LSAVE: LPT's save table (big model only)
140 * UBIFS_LPT_NODE_CNT: count of LPT node types
141 * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type
142 */
143 enum {
144 UBIFS_LPT_PNODE,
145 UBIFS_LPT_NNODE,
146 UBIFS_LPT_LTAB,
147 UBIFS_LPT_LSAVE,
148 UBIFS_LPT_NODE_CNT,
149 UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1,
150 };
151
152 /*
153 * UBIFS inode types.
154 *
155 * UBIFS_ITYPE_REG: regular file
156 * UBIFS_ITYPE_DIR: directory
157 * UBIFS_ITYPE_LNK: soft link
158 * UBIFS_ITYPE_BLK: block device node
159 * UBIFS_ITYPE_CHR: character device node
160 * UBIFS_ITYPE_FIFO: fifo
161 * UBIFS_ITYPE_SOCK: socket
162 * UBIFS_ITYPES_CNT: count of supported file types
163 */
164 enum {
165 UBIFS_ITYPE_REG,
166 UBIFS_ITYPE_DIR,
167 UBIFS_ITYPE_LNK,
168 UBIFS_ITYPE_BLK,
169 UBIFS_ITYPE_CHR,
170 UBIFS_ITYPE_FIFO,
171 UBIFS_ITYPE_SOCK,
172 UBIFS_ITYPES_CNT,
173 };
174
175 /*
176 * Supported key hash functions.
177 *
178 * UBIFS_KEY_HASH_R5: R5 hash
179 * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name
180 */
181 enum {
182 UBIFS_KEY_HASH_R5,
183 UBIFS_KEY_HASH_TEST,
184 };
185
186 /*
187 * Supported key formats.
188 *
189 * UBIFS_SIMPLE_KEY_FMT: simple key format
190 */
191 enum {
192 UBIFS_SIMPLE_KEY_FMT,
193 };
194
195 /*
196 * The simple key format uses 29 bits for storing UBIFS block number and hash
197 * value.
198 */
199 #define UBIFS_S_KEY_BLOCK_BITS 29
200 #define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF
201 #define UBIFS_S_KEY_HASH_BITS UBIFS_S_KEY_BLOCK_BITS
202 #define UBIFS_S_KEY_HASH_MASK UBIFS_S_KEY_BLOCK_MASK
203
204 /*
205 * Key types.
206 *
207 * UBIFS_INO_KEY: inode node key
208 * UBIFS_DATA_KEY: data node key
209 * UBIFS_DENT_KEY: directory entry node key
210 * UBIFS_XENT_KEY: extended attribute entry key
211 * UBIFS_KEY_TYPES_CNT: number of supported key types
212 */
213 enum {
214 UBIFS_INO_KEY,
215 UBIFS_DATA_KEY,
216 UBIFS_DENT_KEY,
217 UBIFS_XENT_KEY,
218 UBIFS_KEY_TYPES_CNT,
219 };
220
221 /* Count of LEBs reserved for the superblock area */
222 #define UBIFS_SB_LEBS 1
223 /* Count of LEBs reserved for the master area */
224 #define UBIFS_MST_LEBS 2
225
226 /* First LEB of the superblock area */
227 #define UBIFS_SB_LNUM 0
228 /* First LEB of the master area */
229 #define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS)
230 /* First LEB of the log area */
231 #define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS)
232
233 /*
234 * The below constants define the absolute minimum values for various UBIFS
235 * media areas. Many of them actually depend of flash geometry and the FS
236 * configuration (number of journal heads, orphan LEBs, etc). This means that
237 * the smallest volume size which can be used for UBIFS cannot be pre-defined
238 * by these constants. The file-system that meets the below limitation will not
239 * necessarily mount. UBIFS does run-time calculations and validates the FS
240 * size.
241 */
242
243 /* Minimum number of logical eraseblocks in the log */
244 #define UBIFS_MIN_LOG_LEBS 2
245 /* Minimum number of bud logical eraseblocks (one for each head) */
246 #define UBIFS_MIN_BUD_LEBS 3
247 /* Minimum number of journal logical eraseblocks */
248 #define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS)
249 /* Minimum number of LPT area logical eraseblocks */
250 #define UBIFS_MIN_LPT_LEBS 2
251 /* Minimum number of orphan area logical eraseblocks */
252 #define UBIFS_MIN_ORPH_LEBS 1
253 /*
254 * Minimum number of main area logical eraseblocks (buds, 3 for the index, 1
255 * for GC, 1 for deletions, and at least 1 for committed data).
256 */
257 #define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 6)
258
259 /* Minimum number of logical eraseblocks */
260 #define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \
261 UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \
262 UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS)
263
264 /* Node sizes (N.B. these are guaranteed to be multiples of 8) */
265 #define UBIFS_CH_SZ sizeof(struct ubifs_ch)
266 #define UBIFS_INO_NODE_SZ sizeof(struct ubifs_ino_node)
267 #define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node)
268 #define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node)
269 #define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node)
270 #define UBIFS_PAD_NODE_SZ sizeof(struct ubifs_pad_node)
271 #define UBIFS_SB_NODE_SZ sizeof(struct ubifs_sb_node)
272 #define UBIFS_MST_NODE_SZ sizeof(struct ubifs_mst_node)
273 #define UBIFS_REF_NODE_SZ sizeof(struct ubifs_ref_node)
274 #define UBIFS_IDX_NODE_SZ sizeof(struct ubifs_idx_node)
275 #define UBIFS_CS_NODE_SZ sizeof(struct ubifs_cs_node)
276 #define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node)
277 #define UBIFS_AUTH_NODE_SZ sizeof(struct ubifs_auth_node)
278 #define UBIFS_SIG_NODE_SZ sizeof(struct ubifs_sig_node)
279
280 /* Extended attribute entry nodes are identical to directory entry nodes */
281 #define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ
282 /* Only this does not have to be multiple of 8 bytes */
283 #define UBIFS_BRANCH_SZ sizeof(struct ubifs_branch)
284
285 /* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */
286 #define UBIFS_MAX_DATA_NODE_SZ (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE)
287 #define UBIFS_MAX_INO_NODE_SZ (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA)
288 #define UBIFS_MAX_DENT_NODE_SZ (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1)
289 #define UBIFS_MAX_XENT_NODE_SZ UBIFS_MAX_DENT_NODE_SZ
290
291 /* The largest UBIFS node */
292 #define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ
293
294 /* The maxmimum size of a hash, enough for sha512 */
295 #define UBIFS_MAX_HASH_LEN 64
296
297 /* The maxmimum size of a hmac, enough for hmac(sha512) */
298 #define UBIFS_MAX_HMAC_LEN 64
299
300 /*
301 * xattr name of UBIFS encryption context, we don't use a prefix
302 * nor a long name to not waste space on the flash.
303 */
304 #define UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT "c"
305
306 /* Type field in ubifs_sig_node */
307 #define UBIFS_SIGNATURE_TYPE_PKCS7 1
308
309 /*
310 * On-flash inode flags.
311 *
312 * UBIFS_COMPR_FL: use compression for this inode
313 * UBIFS_SYNC_FL: I/O on this inode has to be synchronous
314 * UBIFS_IMMUTABLE_FL: inode is immutable
315 * UBIFS_APPEND_FL: writes to the inode may only append data
316 * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous
317 * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value
318 * UBIFS_CRYPT_FL: use encryption for this inode
319 *
320 * Note, these are on-flash flags which correspond to ioctl flags
321 * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not
322 * have to be the same.
323 */
324 enum {
325 UBIFS_COMPR_FL = 0x01,
326 UBIFS_SYNC_FL = 0x02,
327 UBIFS_IMMUTABLE_FL = 0x04,
328 UBIFS_APPEND_FL = 0x08,
329 UBIFS_DIRSYNC_FL = 0x10,
330 UBIFS_XATTR_FL = 0x20,
331 UBIFS_CRYPT_FL = 0x40,
332 };
333
334 /* Inode flag bits used by UBIFS */
335 #define UBIFS_FL_MASK 0x0000001F
336
337 /*
338 * UBIFS compression algorithms.
339 *
340 * UBIFS_COMPR_NONE: no compression
341 * UBIFS_COMPR_LZO: LZO compression
342 * UBIFS_COMPR_ZLIB: ZLIB compression
343 * UBIFS_COMPR_ZSTD: ZSTD compression
344 * UBIFS_COMPR_TYPES_CNT: count of supported compression types
345 */
346 enum {
347 UBIFS_COMPR_NONE,
348 UBIFS_COMPR_LZO,
349 UBIFS_COMPR_ZLIB,
350 UBIFS_COMPR_ZSTD,
351 UBIFS_COMPR_TYPES_CNT,
352 };
353
354 /*
355 * UBIFS node types.
356 *
357 * UBIFS_INO_NODE: inode node
358 * UBIFS_DATA_NODE: data node
359 * UBIFS_DENT_NODE: directory entry node
360 * UBIFS_XENT_NODE: extended attribute node
361 * UBIFS_TRUN_NODE: truncation node
362 * UBIFS_PAD_NODE: padding node
363 * UBIFS_SB_NODE: superblock node
364 * UBIFS_MST_NODE: master node
365 * UBIFS_REF_NODE: LEB reference node
366 * UBIFS_IDX_NODE: index node
367 * UBIFS_CS_NODE: commit start node
368 * UBIFS_ORPH_NODE: orphan node
369 * UBIFS_AUTH_NODE: authentication node
370 * UBIFS_SIG_NODE: signature node
371 * UBIFS_NODE_TYPES_CNT: count of supported node types
372 *
373 * Note, we index arrays by these numbers, so keep them low and contiguous.
374 * Node type constants for inodes, direntries and so on have to be the same as
375 * corresponding key type constants.
376 */
377 enum {
378 UBIFS_INO_NODE,
379 UBIFS_DATA_NODE,
380 UBIFS_DENT_NODE,
381 UBIFS_XENT_NODE,
382 UBIFS_TRUN_NODE,
383 UBIFS_PAD_NODE,
384 UBIFS_SB_NODE,
385 UBIFS_MST_NODE,
386 UBIFS_REF_NODE,
387 UBIFS_IDX_NODE,
388 UBIFS_CS_NODE,
389 UBIFS_ORPH_NODE,
390 UBIFS_AUTH_NODE,
391 UBIFS_SIG_NODE,
392 UBIFS_NODE_TYPES_CNT,
393 };
394
395 /*
396 * Master node flags.
397 *
398 * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty
399 * UBIFS_MST_NO_ORPHS: no orphan inodes present
400 * UBIFS_MST_RCVRY: written by recovery
401 */
402 enum {
403 UBIFS_MST_DIRTY = 1,
404 UBIFS_MST_NO_ORPHS = 2,
405 UBIFS_MST_RCVRY = 4,
406 };
407
408 /*
409 * Node group type (used by recovery to recover whole group or none).
410 *
411 * UBIFS_NO_NODE_GROUP: this node is not part of a group
412 * UBIFS_IN_NODE_GROUP: this node is a part of a group
413 * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group
414 */
415 enum {
416 UBIFS_NO_NODE_GROUP = 0,
417 UBIFS_IN_NODE_GROUP,
418 UBIFS_LAST_OF_NODE_GROUP,
419 };
420
421 /*
422 * Superblock flags.
423 *
424 * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set
425 * UBIFS_FLG_SPACE_FIXUP: first-mount "fixup" of free space within LEBs needed
426 * UBIFS_FLG_DOUBLE_HASH: store a 32bit cookie in directory entry nodes to
427 * support 64bit cookies for lookups by hash
428 * UBIFS_FLG_ENCRYPTION: this filesystem contains encrypted files
429 * UBIFS_FLG_AUTHENTICATION: this filesystem contains hashes for authentication
430 */
431 enum {
432 UBIFS_FLG_BIGLPT = 0x02,
433 UBIFS_FLG_SPACE_FIXUP = 0x04,
434 UBIFS_FLG_DOUBLE_HASH = 0x08,
435 UBIFS_FLG_ENCRYPTION = 0x10,
436 UBIFS_FLG_AUTHENTICATION = 0x20,
437 };
438
439 #define UBIFS_FLG_MASK (UBIFS_FLG_BIGLPT | UBIFS_FLG_SPACE_FIXUP | \
440 UBIFS_FLG_DOUBLE_HASH | UBIFS_FLG_ENCRYPTION | \
441 UBIFS_FLG_AUTHENTICATION)
442
443 /**
444 * struct ubifs_ch - common header node.
445 * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC)
446 * @crc: CRC-32 checksum of the node header
447 * @sqnum: sequence number
448 * @len: full node length
449 * @node_type: node type
450 * @group_type: node group type
451 * @padding: reserved for future, zeroes
452 *
453 * Every UBIFS node starts with this common part. If the node has a key, the
454 * key always goes next.
455 */
456 struct ubifs_ch {
457 __le32 magic;
458 __le32 crc;
459 __le64 sqnum;
460 __le32 len;
461 __u8 node_type;
462 __u8 group_type;
463 __u8 padding[2];
464 } __packed;
465
466 /**
467 * union ubifs_dev_desc - device node descriptor.
468 * @new: new type device descriptor
469 * @huge: huge type device descriptor
470 *
471 * This data structure describes major/minor numbers of a device node. In an
472 * inode is a device node then its data contains an object of this type. UBIFS
473 * uses standard Linux "new" and "huge" device node encodings.
474 */
475 union ubifs_dev_desc {
476 __le32 new;
477 __le64 huge;
478 } __packed;
479
480 /**
481 * struct ubifs_ino_node - inode node.
482 * @ch: common header
483 * @key: node key
484 * @creat_sqnum: sequence number at time of creation
485 * @size: inode size in bytes (amount of uncompressed data)
486 * @atime_sec: access time seconds
487 * @ctime_sec: creation time seconds
488 * @mtime_sec: modification time seconds
489 * @atime_nsec: access time nanoseconds
490 * @ctime_nsec: creation time nanoseconds
491 * @mtime_nsec: modification time nanoseconds
492 * @nlink: number of hard links
493 * @uid: owner ID
494 * @gid: group ID
495 * @mode: access flags
496 * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc)
497 * @data_len: inode data length
498 * @xattr_cnt: count of extended attributes this inode has
499 * @xattr_size: summarized size of all extended attributes in bytes
500 * @padding1: reserved for future, zeroes
501 * @xattr_names: sum of lengths of all extended attribute names belonging to
502 * this inode
503 * @compr_type: compression type used for this inode
504 * @padding2: reserved for future, zeroes
505 * @data: data attached to the inode
506 *
507 * Note, even though inode compression type is defined by @compr_type, some
508 * nodes of this inode may be compressed with different compressor - this
509 * happens if compression type is changed while the inode already has data
510 * nodes. But @compr_type will be use for further writes to the inode.
511 *
512 * Note, do not forget to amend 'zero_ino_node_unused()' function when changing
513 * the padding fields.
514 */
515 struct ubifs_ino_node {
516 struct ubifs_ch ch;
517 __u8 key[UBIFS_MAX_KEY_LEN];
518 __le64 creat_sqnum;
519 __le64 size;
520 __le64 atime_sec;
521 __le64 ctime_sec;
522 __le64 mtime_sec;
523 __le32 atime_nsec;
524 __le32 ctime_nsec;
525 __le32 mtime_nsec;
526 __le32 nlink;
527 __le32 uid;
528 __le32 gid;
529 __le32 mode;
530 __le32 flags;
531 __le32 data_len;
532 __le32 xattr_cnt;
533 __le32 xattr_size;
534 __u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */
535 __le32 xattr_names;
536 __le16 compr_type;
537 __u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */
538 __u8 data[];
539 } __packed;
540
541 /**
542 * struct ubifs_dent_node - directory entry node.
543 * @ch: common header
544 * @key: node key
545 * @inum: target inode number
546 * @padding1: reserved for future, zeroes
547 * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc)
548 * @nlen: name length
549 * @cookie: A 32bits random number, used to construct a 64bits
550 * identifier.
551 * @name: zero-terminated name
552 *
553 * Note, do not forget to amend 'zero_dent_node_unused()' function when
554 * changing the padding fields.
555 */
556 struct ubifs_dent_node {
557 struct ubifs_ch ch;
558 __u8 key[UBIFS_MAX_KEY_LEN];
559 __le64 inum;
560 __u8 padding1;
561 __u8 type;
562 __le16 nlen;
563 __le32 cookie;
564 __u8 name[];
565 } __packed;
566
567 /**
568 * struct ubifs_data_node - data node.
569 * @ch: common header
570 * @key: node key
571 * @size: uncompressed data size in bytes
572 * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc)
573 * @compr_size: compressed data size in bytes, only valid when data is encrypted
574 * @data: data
575 *
576 */
577 struct ubifs_data_node {
578 struct ubifs_ch ch;
579 __u8 key[UBIFS_MAX_KEY_LEN];
580 __le32 size;
581 __le16 compr_type;
582 __le16 compr_size;
583 __u8 data[];
584 } __packed;
585
586 /**
587 * struct ubifs_trun_node - truncation node.
588 * @ch: common header
589 * @inum: truncated inode number
590 * @padding: reserved for future, zeroes
591 * @old_size: size before truncation
592 * @new_size: size after truncation
593 *
594 * This node exists only in the journal and never goes to the main area. Note,
595 * do not forget to amend 'zero_trun_node_unused()' function when changing the
596 * padding fields.
597 */
598 struct ubifs_trun_node {
599 struct ubifs_ch ch;
600 __le32 inum;
601 __u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */
602 __le64 old_size;
603 __le64 new_size;
604 } __packed;
605
606 /**
607 * struct ubifs_pad_node - padding node.
608 * @ch: common header
609 * @pad_len: how many bytes after this node are unused (because padded)
610 * @padding: reserved for future, zeroes
611 */
612 struct ubifs_pad_node {
613 struct ubifs_ch ch;
614 __le32 pad_len;
615 } __packed;
616
617 /**
618 * struct ubifs_sb_node - superblock node.
619 * @ch: common header
620 * @padding: reserved for future, zeroes
621 * @key_hash: type of hash function used in keys
622 * @key_fmt: format of the key
623 * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc)
624 * @min_io_size: minimal input/output unit size
625 * @leb_size: logical eraseblock size in bytes
626 * @leb_cnt: count of LEBs used by file-system
627 * @max_leb_cnt: maximum count of LEBs used by file-system
628 * @max_bud_bytes: maximum amount of data stored in buds
629 * @log_lebs: log size in logical eraseblocks
630 * @lpt_lebs: number of LEBs used for lprops table
631 * @orph_lebs: number of LEBs used for recording orphans
632 * @jhead_cnt: count of journal heads
633 * @fanout: tree fanout (max. number of links per indexing node)
634 * @lsave_cnt: number of LEB numbers in LPT's save table
635 * @fmt_version: UBIFS on-flash format version
636 * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
637 * @padding1: reserved for future, zeroes
638 * @rp_uid: reserve pool UID
639 * @rp_gid: reserve pool GID
640 * @rp_size: size of the reserved pool in bytes
641 * @padding2: reserved for future, zeroes
642 * @time_gran: time granularity in nanoseconds
643 * @uuid: UUID generated when the file system image was created
644 * @ro_compat_version: UBIFS R/O compatibility version
645 * @hmac: HMAC to authenticate the superblock node
646 * @hmac_wkm: HMAC of a well known message (the string "UBIFS") as a convenience
647 * to the user to check if the correct key is passed.
648 * @hash_algo: The hash algo used for this filesystem (one of enum hash_algo)
649 * @hash_mst: hash of the master node, only valid for signed images in which the
650 * master node does not contain a hmac
651 */
652 struct ubifs_sb_node {
653 struct ubifs_ch ch;
654 __u8 padding[2];
655 __u8 key_hash;
656 __u8 key_fmt;
657 __le32 flags;
658 __le32 min_io_size;
659 __le32 leb_size;
660 __le32 leb_cnt;
661 __le32 max_leb_cnt;
662 __le64 max_bud_bytes;
663 __le32 log_lebs;
664 __le32 lpt_lebs;
665 __le32 orph_lebs;
666 __le32 jhead_cnt;
667 __le32 fanout;
668 __le32 lsave_cnt;
669 __le32 fmt_version;
670 __le16 default_compr;
671 __u8 padding1[2];
672 __le32 rp_uid;
673 __le32 rp_gid;
674 __le64 rp_size;
675 __le32 time_gran;
676 __u8 uuid[16];
677 __le32 ro_compat_version;
678 __u8 hmac[UBIFS_MAX_HMAC_LEN];
679 __u8 hmac_wkm[UBIFS_MAX_HMAC_LEN];
680 __le16 hash_algo;
681 __u8 hash_mst[UBIFS_MAX_HASH_LEN];
682 __u8 padding2[3774];
683 } __packed;
684
685 /**
686 * struct ubifs_mst_node - master node.
687 * @ch: common header
688 * @highest_inum: highest inode number in the committed index
689 * @cmt_no: commit number
690 * @flags: various flags (%UBIFS_MST_DIRTY, etc)
691 * @log_lnum: start of the log
692 * @root_lnum: LEB number of the root indexing node
693 * @root_offs: offset within @root_lnum
694 * @root_len: root indexing node length
695 * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was
696 * not reserved and should be reserved on mount)
697 * @ihead_lnum: LEB number of index head
698 * @ihead_offs: offset of index head
699 * @index_size: size of index on flash
700 * @total_free: total free space in bytes
701 * @total_dirty: total dirty space in bytes
702 * @total_used: total used space in bytes (includes only data LEBs)
703 * @total_dead: total dead space in bytes (includes only data LEBs)
704 * @total_dark: total dark space in bytes (includes only data LEBs)
705 * @lpt_lnum: LEB number of LPT root nnode
706 * @lpt_offs: offset of LPT root nnode
707 * @nhead_lnum: LEB number of LPT head
708 * @nhead_offs: offset of LPT head
709 * @ltab_lnum: LEB number of LPT's own lprops table
710 * @ltab_offs: offset of LPT's own lprops table
711 * @lsave_lnum: LEB number of LPT's save table (big model only)
712 * @lsave_offs: offset of LPT's save table (big model only)
713 * @lscan_lnum: LEB number of last LPT scan
714 * @empty_lebs: number of empty logical eraseblocks
715 * @idx_lebs: number of indexing logical eraseblocks
716 * @leb_cnt: count of LEBs used by file-system
717 * @hash_root_idx: the hash of the root index node
718 * @hash_lpt: the hash of the LPT
719 * @hmac: HMAC to authenticate the master node
720 * @padding: reserved for future, zeroes
721 */
722 struct ubifs_mst_node {
723 struct ubifs_ch ch;
724 __le64 highest_inum;
725 __le64 cmt_no;
726 __le32 flags;
727 __le32 log_lnum;
728 __le32 root_lnum;
729 __le32 root_offs;
730 __le32 root_len;
731 __le32 gc_lnum;
732 __le32 ihead_lnum;
733 __le32 ihead_offs;
734 __le64 index_size;
735 __le64 total_free;
736 __le64 total_dirty;
737 __le64 total_used;
738 __le64 total_dead;
739 __le64 total_dark;
740 __le32 lpt_lnum;
741 __le32 lpt_offs;
742 __le32 nhead_lnum;
743 __le32 nhead_offs;
744 __le32 ltab_lnum;
745 __le32 ltab_offs;
746 __le32 lsave_lnum;
747 __le32 lsave_offs;
748 __le32 lscan_lnum;
749 __le32 empty_lebs;
750 __le32 idx_lebs;
751 __le32 leb_cnt;
752 __u8 hash_root_idx[UBIFS_MAX_HASH_LEN];
753 __u8 hash_lpt[UBIFS_MAX_HASH_LEN];
754 __u8 hmac[UBIFS_MAX_HMAC_LEN];
755 __u8 padding[152];
756 } __packed;
757
758 /**
759 * struct ubifs_ref_node - logical eraseblock reference node.
760 * @ch: common header
761 * @lnum: the referred logical eraseblock number
762 * @offs: start offset in the referred LEB
763 * @jhead: journal head number
764 * @padding: reserved for future, zeroes
765 */
766 struct ubifs_ref_node {
767 struct ubifs_ch ch;
768 __le32 lnum;
769 __le32 offs;
770 __le32 jhead;
771 __u8 padding[28];
772 } __packed;
773
774 /**
775 * struct ubifs_auth_node - node for authenticating other nodes
776 * @ch: common header
777 * @hmac: The HMAC
778 */
779 struct ubifs_auth_node {
780 struct ubifs_ch ch;
781 __u8 hmac[];
782 } __packed;
783
784 /**
785 * struct ubifs_sig_node - node for signing other nodes
786 * @ch: common header
787 * @type: type of the signature, currently only UBIFS_SIGNATURE_TYPE_PKCS7
788 * supported
789 * @len: The length of the signature data
790 * @padding: reserved for future, zeroes
791 * @sig: The signature data
792 */
793 struct ubifs_sig_node {
794 struct ubifs_ch ch;
795 __le32 type;
796 __le32 len;
797 __u8 padding[32];
798 __u8 sig[];
799 } __packed;
800
801 /**
802 * struct ubifs_branch - key/reference/length branch
803 * @lnum: LEB number of the target node
804 * @offs: offset within @lnum
805 * @len: target node length
806 * @key: key
807 *
808 * In an authenticated UBIFS we have the hash of the referenced node after @key.
809 * This can't be added to the struct type definition because @key is a
810 * dynamically sized element already.
811 */
812 struct ubifs_branch {
813 __le32 lnum;
814 __le32 offs;
815 __le32 len;
816 __u8 key[];
817 } __packed;
818
819 /**
820 * struct ubifs_idx_node - indexing node.
821 * @ch: common header
822 * @child_cnt: number of child index nodes
823 * @level: tree level
824 * @branches: LEB number / offset / length / key branches
825 */
826 struct ubifs_idx_node {
827 struct ubifs_ch ch;
828 __le16 child_cnt;
829 __le16 level;
830 __u8 branches[];
831 } __packed;
832
833 /**
834 * struct ubifs_cs_node - commit start node.
835 * @ch: common header
836 * @cmt_no: commit number
837 */
838 struct ubifs_cs_node {
839 struct ubifs_ch ch;
840 __le64 cmt_no;
841 } __packed;
842
843 /**
844 * struct ubifs_orph_node - orphan node.
845 * @ch: common header
846 * @cmt_no: commit number (also top bit is set on the last node of the commit)
847 * @inos: inode numbers of orphans
848 */
849 struct ubifs_orph_node {
850 struct ubifs_ch ch;
851 __le64 cmt_no;
852 __le64 inos[];
853 } __packed;
854
855 #endif /* __UBIFS_MEDIA_H__ */
856
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