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1/*
2 * This file is part of UBIFS.
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors: Artem Bityutskiy (Битюцкий Артём)
20 * Adrian Hunter
21 */
22
23/*
24 * This header contains various key-related definitions and helper function.
25 * UBIFS allows several key schemes, so we access key fields only via these
26 * helpers. At the moment only one key scheme is supported.
27 *
28 * Simple key scheme
29 * ~~~~~~~~~~~~~~~~~
30 *
31 * Keys are 64-bits long. First 32-bits are inode number (parent inode number
32 * in case of direntry key). Next 3 bits are node type. The last 29 bits are
33 * 4KiB offset in case of inode node, and direntry hash in case of a direntry
34 * node. We use "r5" hash borrowed from reiserfs.
35 */
36
37#ifndef __UBIFS_KEY_H__
38#define __UBIFS_KEY_H__
39
40/**
41 * key_mask_hash - mask a valid hash value.
42 * @val: value to be masked
43 *
44 * We use hash values as offset in directories, so values %0 and %1 are
45 * reserved for "." and "..". %2 is reserved for "end of readdir" marker. This
46 * function makes sure the reserved values are not used.
47 */
48static inline uint32_t key_mask_hash(uint32_t hash)
49{
50 hash &= UBIFS_S_KEY_HASH_MASK;
51 if (unlikely(hash <= 2))
52 hash += 3;
53 return hash;
54}
55
56/**
57 * key_r5_hash - R5 hash function (borrowed from reiserfs).
58 * @s: direntry name
59 * @len: name length
60 */
61static inline uint32_t key_r5_hash(const char *s, int len)
62{
63 uint32_t a = 0;
64 const signed char *str = (const signed char *)s;
65
66 while (*str) {
67 a += *str << 4;
68 a += *str >> 4;
69 a *= 11;
70 str++;
71 }
72
73 return key_mask_hash(a);
74}
75
76/**
77 * key_test_hash - testing hash function.
78 * @str: direntry name
79 * @len: name length
80 */
81static inline uint32_t key_test_hash(const char *str, int len)
82{
83 uint32_t a = 0;
84
85 len = min_t(uint32_t, len, 4);
86 memcpy(&a, str, len);
87 return key_mask_hash(a);
88}
89
90/**
91 * ino_key_init - initialize inode key.
92 * @c: UBIFS file-system description object
93 * @key: key to initialize
94 * @inum: inode number
95 */
96static inline void ino_key_init(const struct ubifs_info *c,
97 union ubifs_key *key, ino_t inum)
98{
99 key->u32[0] = inum;
100 key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
101}
102
103/**
104 * ino_key_init_flash - initialize on-flash inode key.
105 * @c: UBIFS file-system description object
106 * @k: key to initialize
107 * @inum: inode number
108 */
109static inline void ino_key_init_flash(const struct ubifs_info *c, void *k,
110 ino_t inum)
111{
112 union ubifs_key *key = k;
113
114 key->j32[0] = cpu_to_le32(inum);
115 key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
116 memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
117}
118
119/**
120 * lowest_ino_key - get the lowest possible inode key.
121 * @c: UBIFS file-system description object
122 * @key: key to initialize
123 * @inum: inode number
124 */
125static inline void lowest_ino_key(const struct ubifs_info *c,
126 union ubifs_key *key, ino_t inum)
127{
128 key->u32[0] = inum;
129 key->u32[1] = 0;
130}
131
132/**
133 * highest_ino_key - get the highest possible inode key.
134 * @c: UBIFS file-system description object
135 * @key: key to initialize
136 * @inum: inode number
137 */
138static inline void highest_ino_key(const struct ubifs_info *c,
139 union ubifs_key *key, ino_t inum)
140{
141 key->u32[0] = inum;
142 key->u32[1] = 0xffffffff;
143}
144
145/**
146 * dent_key_init - initialize directory entry key.
147 * @c: UBIFS file-system description object
148 * @key: key to initialize
149 * @inum: parent inode number
150 * @nm: direntry name and length
151 */
152static inline void dent_key_init(const struct ubifs_info *c,
153 union ubifs_key *key, ino_t inum,
154 const struct qstr *nm)
155{
156 uint32_t hash = c->key_hash(nm->name, nm->len);
157
158 ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
159 key->u32[0] = inum;
160 key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
161}
162
163/**
164 * dent_key_init_hash - initialize directory entry key without re-calculating
165 * hash function.
166 * @c: UBIFS file-system description object
167 * @key: key to initialize
168 * @inum: parent inode number
169 * @hash: direntry name hash
170 */
171static inline void dent_key_init_hash(const struct ubifs_info *c,
172 union ubifs_key *key, ino_t inum,
173 uint32_t hash)
174{
175 ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
176 key->u32[0] = inum;
177 key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
178}
179
180/**
181 * dent_key_init_flash - initialize on-flash directory entry key.
182 * @c: UBIFS file-system description object
183 * @k: key to initialize
184 * @inum: parent inode number
185 * @nm: direntry name and length
186 */
187static inline void dent_key_init_flash(const struct ubifs_info *c, void *k,
188 ino_t inum, const struct qstr *nm)
189{
190 union ubifs_key *key = k;
191 uint32_t hash = c->key_hash(nm->name, nm->len);
192
193 ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
194 key->j32[0] = cpu_to_le32(inum);
195 key->j32[1] = cpu_to_le32(hash |
196 (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
197 memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
198}
199
200/**
201 * lowest_dent_key - get the lowest possible directory entry key.
202 * @c: UBIFS file-system description object
203 * @key: where to store the lowest key
204 * @inum: parent inode number
205 */
206static inline void lowest_dent_key(const struct ubifs_info *c,
207 union ubifs_key *key, ino_t inum)
208{
209 key->u32[0] = inum;
210 key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
211}
212
213/**
214 * xent_key_init - initialize extended attribute entry key.
215 * @c: UBIFS file-system description object
216 * @key: key to initialize
217 * @inum: host inode number
218 * @nm: extended attribute entry name and length
219 */
220static inline void xent_key_init(const struct ubifs_info *c,
221 union ubifs_key *key, ino_t inum,
222 const struct qstr *nm)
223{
224 uint32_t hash = c->key_hash(nm->name, nm->len);
225
226 ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
227 key->u32[0] = inum;
228 key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
229}
230
231/**
232 * xent_key_init_flash - initialize on-flash extended attribute entry key.
233 * @c: UBIFS file-system description object
234 * @k: key to initialize
235 * @inum: host inode number
236 * @nm: extended attribute entry name and length
237 */
238static inline void xent_key_init_flash(const struct ubifs_info *c, void *k,
239 ino_t inum, const struct qstr *nm)
240{
241 union ubifs_key *key = k;
242 uint32_t hash = c->key_hash(nm->name, nm->len);
243
244 ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
245 key->j32[0] = cpu_to_le32(inum);
246 key->j32[1] = cpu_to_le32(hash |
247 (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
248 memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
249}
250
251/**
252 * lowest_xent_key - get the lowest possible extended attribute entry key.
253 * @c: UBIFS file-system description object
254 * @key: where to store the lowest key
255 * @inum: host inode number
256 */
257static inline void lowest_xent_key(const struct ubifs_info *c,
258 union ubifs_key *key, ino_t inum)
259{
260 key->u32[0] = inum;
261 key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
262}
263
264/**
265 * data_key_init - initialize data key.
266 * @c: UBIFS file-system description object
267 * @key: key to initialize
268 * @inum: inode number
269 * @block: block number
270 */
271static inline void data_key_init(const struct ubifs_info *c,
272 union ubifs_key *key, ino_t inum,
273 unsigned int block)
274{
275 ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
276 key->u32[0] = inum;
277 key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
278}
279
280/**
281 * highest_data_key - get the highest possible data key for an inode.
282 * @c: UBIFS file-system description object
283 * @key: key to initialize
284 * @inum: inode number
285 */
286static inline void highest_data_key(const struct ubifs_info *c,
287 union ubifs_key *key, ino_t inum)
288{
289 data_key_init(c, key, inum, UBIFS_S_KEY_BLOCK_MASK);
290}
291
292/**
293 * trun_key_init - initialize truncation node key.
294 * @c: UBIFS file-system description object
295 * @key: key to initialize
296 * @inum: inode number
297 *
298 * Note, UBIFS does not have truncation keys on the media and this function is
299 * only used for purposes of replay.
300 */
301static inline void trun_key_init(const struct ubifs_info *c,
302 union ubifs_key *key, ino_t inum)
303{
304 key->u32[0] = inum;
305 key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
306}
307
308/**
309 * invalid_key_init - initialize invalid node key.
310 * @c: UBIFS file-system description object
311 * @key: key to initialize
312 *
313 * This is a helper function which marks a @key object as invalid.
314 */
315static inline void invalid_key_init(const struct ubifs_info *c,
316 union ubifs_key *key)
317{
318 key->u32[0] = 0xDEADBEAF;
319 key->u32[1] = UBIFS_INVALID_KEY;
320}
321
322/**
323 * key_type - get key type.
324 * @c: UBIFS file-system description object
325 * @key: key to get type of
326 */
327static inline int key_type(const struct ubifs_info *c,
328 const union ubifs_key *key)
329{
330 return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
331}
332
333/**
334 * key_type_flash - get type of a on-flash formatted key.
335 * @c: UBIFS file-system description object
336 * @k: key to get type of
337 */
338static inline int key_type_flash(const struct ubifs_info *c, const void *k)
339{
340 const union ubifs_key *key = k;
341
342 return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
343}
344
345/**
346 * key_inum - fetch inode number from key.
347 * @c: UBIFS file-system description object
348 * @k: key to fetch inode number from
349 */
350static inline ino_t key_inum(const struct ubifs_info *c, const void *k)
351{
352 const union ubifs_key *key = k;
353
354 return key->u32[0];
355}
356
357/**
358 * key_inum_flash - fetch inode number from an on-flash formatted key.
359 * @c: UBIFS file-system description object
360 * @k: key to fetch inode number from
361 */
362static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k)
363{
364 const union ubifs_key *key = k;
365
366 return le32_to_cpu(key->j32[0]);
367}
368
369/**
370 * key_hash - get directory entry hash.
371 * @c: UBIFS file-system description object
372 * @key: the key to get hash from
373 */
374static inline uint32_t key_hash(const struct ubifs_info *c,
375 const union ubifs_key *key)
376{
377 return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
378}
379
380/**
381 * key_hash_flash - get directory entry hash from an on-flash formatted key.
382 * @c: UBIFS file-system description object
383 * @k: the key to get hash from
384 */
385static inline uint32_t key_hash_flash(const struct ubifs_info *c, const void *k)
386{
387 const union ubifs_key *key = k;
388
389 return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
390}
391
392/**
393 * key_block - get data block number.
394 * @c: UBIFS file-system description object
395 * @key: the key to get the block number from
396 */
397static inline unsigned int key_block(const struct ubifs_info *c,
398 const union ubifs_key *key)
399{
400 return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
401}
402
403/**
404 * key_block_flash - get data block number from an on-flash formatted key.
405 * @c: UBIFS file-system description object
406 * @k: the key to get the block number from
407 */
408static inline unsigned int key_block_flash(const struct ubifs_info *c,
409 const void *k)
410{
411 const union ubifs_key *key = k;
412
413 return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK;
414}
415
416/**
417 * key_read - transform a key to in-memory format.
418 * @c: UBIFS file-system description object
419 * @from: the key to transform
420 * @to: the key to store the result
421 */
422static inline void key_read(const struct ubifs_info *c, const void *from,
423 union ubifs_key *to)
424{
425 const union ubifs_key *f = from;
426
427 to->u32[0] = le32_to_cpu(f->j32[0]);
428 to->u32[1] = le32_to_cpu(f->j32[1]);
429}
430
431/**
432 * key_write - transform a key from in-memory format.
433 * @c: UBIFS file-system description object
434 * @from: the key to transform
435 * @to: the key to store the result
436 */
437static inline void key_write(const struct ubifs_info *c,
438 const union ubifs_key *from, void *to)
439{
440 union ubifs_key *t = to;
441
442 t->j32[0] = cpu_to_le32(from->u32[0]);
443 t->j32[1] = cpu_to_le32(from->u32[1]);
444 memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
445}
446
447/**
448 * key_write_idx - transform a key from in-memory format for the index.
449 * @c: UBIFS file-system description object
450 * @from: the key to transform
451 * @to: the key to store the result
452 */
453static inline void key_write_idx(const struct ubifs_info *c,
454 const union ubifs_key *from, void *to)
455{
456 union ubifs_key *t = to;
457
458 t->j32[0] = cpu_to_le32(from->u32[0]);
459 t->j32[1] = cpu_to_le32(from->u32[1]);
460}
461
462/**
463 * key_copy - copy a key.
464 * @c: UBIFS file-system description object
465 * @from: the key to copy from
466 * @to: the key to copy to
467 */
468static inline void key_copy(const struct ubifs_info *c,
469 const union ubifs_key *from, union ubifs_key *to)
470{
471 to->u64[0] = from->u64[0];
472}
473
474/**
475 * keys_cmp - compare keys.
476 * @c: UBIFS file-system description object
477 * @key1: the first key to compare
478 * @key2: the second key to compare
479 *
480 * This function compares 2 keys and returns %-1 if @key1 is less than
481 * @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2.
482 */
483static inline int keys_cmp(const struct ubifs_info *c,
484 const union ubifs_key *key1,
485 const union ubifs_key *key2)
486{
487 if (key1->u32[0] < key2->u32[0])
488 return -1;
489 if (key1->u32[0] > key2->u32[0])
490 return 1;
491 if (key1->u32[1] < key2->u32[1])
492 return -1;
493 if (key1->u32[1] > key2->u32[1])
494 return 1;
495
496 return 0;
497}
498
499/**
500 * keys_eq - determine if keys are equivalent.
501 * @c: UBIFS file-system description object
502 * @key1: the first key to compare
503 * @key2: the second key to compare
504 *
505 * This function compares 2 keys and returns %1 if @key1 is equal to @key2 and
506 * %0 if not.
507 */
508static inline int keys_eq(const struct ubifs_info *c,
509 const union ubifs_key *key1,
510 const union ubifs_key *key2)
511{
512 if (key1->u32[0] != key2->u32[0])
513 return 0;
514 if (key1->u32[1] != key2->u32[1])
515 return 0;
516 return 1;
517}
518
519/**
520 * is_hash_key - is a key vulnerable to hash collisions.
521 * @c: UBIFS file-system description object
522 * @key: key
523 *
524 * This function returns %1 if @key is a hashed key or %0 otherwise.
525 */
526static inline int is_hash_key(const struct ubifs_info *c,
527 const union ubifs_key *key)
528{
529 int type = key_type(c, key);
530
531 return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY;
532}
533
534/**
535 * key_max_inode_size - get maximum file size allowed by current key format.
536 * @c: UBIFS file-system description object
537 */
538static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
539{
540 switch (c->key_fmt) {
541 case UBIFS_SIMPLE_KEY_FMT:
542 return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
543 default:
544 return 0;
545 }
546}
547
548#endif /* !__UBIFS_KEY_H__ */
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 header contains various key-related definitions and helper function.
13 * UBIFS allows several key schemes, so we access key fields only via these
14 * helpers. At the moment only one key scheme is supported.
15 *
16 * Simple key scheme
17 * ~~~~~~~~~~~~~~~~~
18 *
19 * Keys are 64-bits long. First 32-bits are inode number (parent inode number
20 * in case of direntry key). Next 3 bits are node type. The last 29 bits are
21 * 4KiB offset in case of inode node, and direntry hash in case of a direntry
22 * node. We use "r5" hash borrowed from reiserfs.
23 */
24
25/*
26 * Lot's of the key helpers require a struct ubifs_info *c as the first parameter.
27 * But we are not using it at all currently. That's designed for future extensions of
28 * different c->key_format. But right now, there is only one key type, UBIFS_SIMPLE_KEY_FMT.
29 */
30
31#ifndef __UBIFS_KEY_H__
32#define __UBIFS_KEY_H__
33
34/**
35 * key_mask_hash - mask a valid hash value.
36 * @val: value to be masked
37 *
38 * We use hash values as offset in directories, so values %0 and %1 are
39 * reserved for "." and "..". %2 is reserved for "end of readdir" marker. This
40 * function makes sure the reserved values are not used.
41 */
42static inline uint32_t key_mask_hash(uint32_t hash)
43{
44 hash &= UBIFS_S_KEY_HASH_MASK;
45 if (unlikely(hash <= 2))
46 hash += 3;
47 return hash;
48}
49
50/**
51 * key_r5_hash - R5 hash function (borrowed from reiserfs).
52 * @s: direntry name
53 * @len: name length
54 */
55static inline uint32_t key_r5_hash(const char *s, int len)
56{
57 uint32_t a = 0;
58 const signed char *str = (const signed char *)s;
59
60 while (len--) {
61 a += *str << 4;
62 a += *str >> 4;
63 a *= 11;
64 str++;
65 }
66
67 return key_mask_hash(a);
68}
69
70/**
71 * key_test_hash - testing hash function.
72 * @str: direntry name
73 * @len: name length
74 */
75static inline uint32_t key_test_hash(const char *str, int len)
76{
77 uint32_t a = 0;
78
79 len = min_t(uint32_t, len, 4);
80 memcpy(&a, str, len);
81 return key_mask_hash(a);
82}
83
84/**
85 * ino_key_init - initialize inode key.
86 * @c: UBIFS file-system description object
87 * @key: key to initialize
88 * @inum: inode number
89 */
90static inline void ino_key_init(const struct ubifs_info *c,
91 union ubifs_key *key, ino_t inum)
92{
93 key->u32[0] = inum;
94 key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
95}
96
97/**
98 * ino_key_init_flash - initialize on-flash inode key.
99 * @c: UBIFS file-system description object
100 * @k: key to initialize
101 * @inum: inode number
102 */
103static inline void ino_key_init_flash(const struct ubifs_info *c, void *k,
104 ino_t inum)
105{
106 union ubifs_key *key = k;
107
108 key->j32[0] = cpu_to_le32(inum);
109 key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
110 memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
111}
112
113/**
114 * lowest_ino_key - get the lowest possible inode key.
115 * @c: UBIFS file-system description object
116 * @key: key to initialize
117 * @inum: inode number
118 */
119static inline void lowest_ino_key(const struct ubifs_info *c,
120 union ubifs_key *key, ino_t inum)
121{
122 key->u32[0] = inum;
123 key->u32[1] = 0;
124}
125
126/**
127 * highest_ino_key - get the highest possible inode key.
128 * @c: UBIFS file-system description object
129 * @key: key to initialize
130 * @inum: inode number
131 */
132static inline void highest_ino_key(const struct ubifs_info *c,
133 union ubifs_key *key, ino_t inum)
134{
135 key->u32[0] = inum;
136 key->u32[1] = 0xffffffff;
137}
138
139/**
140 * dent_key_init - initialize directory entry key.
141 * @c: UBIFS file-system description object
142 * @key: key to initialize
143 * @inum: parent inode number
144 * @nm: direntry name and length. Not a string when encrypted!
145 */
146static inline void dent_key_init(const struct ubifs_info *c,
147 union ubifs_key *key, ino_t inum,
148 const struct fscrypt_name *nm)
149{
150 uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
151
152 ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
153 key->u32[0] = inum;
154 key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
155}
156
157/**
158 * dent_key_init_hash - initialize directory entry key without re-calculating
159 * hash function.
160 * @c: UBIFS file-system description object
161 * @key: key to initialize
162 * @inum: parent inode number
163 * @hash: direntry name hash
164 */
165static inline void dent_key_init_hash(const struct ubifs_info *c,
166 union ubifs_key *key, ino_t inum,
167 uint32_t hash)
168{
169 ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
170 key->u32[0] = inum;
171 key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
172}
173
174/**
175 * dent_key_init_flash - initialize on-flash directory entry key.
176 * @c: UBIFS file-system description object
177 * @k: key to initialize
178 * @inum: parent inode number
179 * @nm: direntry name and length
180 */
181static inline void dent_key_init_flash(const struct ubifs_info *c, void *k,
182 ino_t inum,
183 const struct fscrypt_name *nm)
184{
185 union ubifs_key *key = k;
186 uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
187
188 ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
189 key->j32[0] = cpu_to_le32(inum);
190 key->j32[1] = cpu_to_le32(hash |
191 (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
192 memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
193}
194
195/**
196 * lowest_dent_key - get the lowest possible directory entry key.
197 * @c: UBIFS file-system description object
198 * @key: where to store the lowest key
199 * @inum: parent inode number
200 */
201static inline void lowest_dent_key(const struct ubifs_info *c,
202 union ubifs_key *key, ino_t inum)
203{
204 key->u32[0] = inum;
205 key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
206}
207
208/**
209 * xent_key_init - initialize extended attribute entry key.
210 * @c: UBIFS file-system description object
211 * @key: key to initialize
212 * @inum: host inode number
213 * @nm: extended attribute entry name and length
214 */
215static inline void xent_key_init(const struct ubifs_info *c,
216 union ubifs_key *key, ino_t inum,
217 const struct fscrypt_name *nm)
218{
219 uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
220
221 ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
222 key->u32[0] = inum;
223 key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
224}
225
226/**
227 * xent_key_init_flash - initialize on-flash extended attribute entry key.
228 * @c: UBIFS file-system description object
229 * @k: key to initialize
230 * @inum: host inode number
231 * @nm: extended attribute entry name and length
232 */
233static inline void xent_key_init_flash(const struct ubifs_info *c, void *k,
234 ino_t inum, const struct fscrypt_name *nm)
235{
236 union ubifs_key *key = k;
237 uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
238
239 ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
240 key->j32[0] = cpu_to_le32(inum);
241 key->j32[1] = cpu_to_le32(hash |
242 (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
243 memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
244}
245
246/**
247 * lowest_xent_key - get the lowest possible extended attribute entry key.
248 * @c: UBIFS file-system description object
249 * @key: where to store the lowest key
250 * @inum: host inode number
251 */
252static inline void lowest_xent_key(const struct ubifs_info *c,
253 union ubifs_key *key, ino_t inum)
254{
255 key->u32[0] = inum;
256 key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
257}
258
259/**
260 * data_key_init - initialize data key.
261 * @c: UBIFS file-system description object
262 * @key: key to initialize
263 * @inum: inode number
264 * @block: block number
265 */
266static inline void data_key_init(const struct ubifs_info *c,
267 union ubifs_key *key, ino_t inum,
268 unsigned int block)
269{
270 ubifs_assert(c, !(block & ~UBIFS_S_KEY_BLOCK_MASK));
271 key->u32[0] = inum;
272 key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
273}
274
275/**
276 * highest_data_key - get the highest possible data key for an inode.
277 * @c: UBIFS file-system description object
278 * @key: key to initialize
279 * @inum: inode number
280 */
281static inline void highest_data_key(const struct ubifs_info *c,
282 union ubifs_key *key, ino_t inum)
283{
284 data_key_init(c, key, inum, UBIFS_S_KEY_BLOCK_MASK);
285}
286
287/**
288 * trun_key_init - initialize truncation node key.
289 * @c: UBIFS file-system description object
290 * @key: key to initialize
291 * @inum: inode number
292 *
293 * Note, UBIFS does not have truncation keys on the media and this function is
294 * only used for purposes of replay.
295 */
296static inline void trun_key_init(const struct ubifs_info *c,
297 union ubifs_key *key, ino_t inum)
298{
299 key->u32[0] = inum;
300 key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
301}
302
303/**
304 * invalid_key_init - initialize invalid node key.
305 * @c: UBIFS file-system description object
306 * @key: key to initialize
307 *
308 * This is a helper function which marks a @key object as invalid.
309 */
310static inline void invalid_key_init(const struct ubifs_info *c,
311 union ubifs_key *key)
312{
313 key->u32[0] = 0xDEADBEAF;
314 key->u32[1] = UBIFS_INVALID_KEY;
315}
316
317/**
318 * key_type - get key type.
319 * @c: UBIFS file-system description object
320 * @key: key to get type of
321 */
322static inline int key_type(const struct ubifs_info *c,
323 const union ubifs_key *key)
324{
325 return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
326}
327
328/**
329 * key_type_flash - get type of a on-flash formatted key.
330 * @c: UBIFS file-system description object
331 * @k: key to get type of
332 */
333static inline int key_type_flash(const struct ubifs_info *c, const void *k)
334{
335 const union ubifs_key *key = k;
336
337 return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
338}
339
340/**
341 * key_inum - fetch inode number from key.
342 * @c: UBIFS file-system description object
343 * @k: key to fetch inode number from
344 */
345static inline ino_t key_inum(const struct ubifs_info *c, const void *k)
346{
347 const union ubifs_key *key = k;
348
349 return key->u32[0];
350}
351
352/**
353 * key_inum_flash - fetch inode number from an on-flash formatted key.
354 * @c: UBIFS file-system description object
355 * @k: key to fetch inode number from
356 */
357static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k)
358{
359 const union ubifs_key *key = k;
360
361 return le32_to_cpu(key->j32[0]);
362}
363
364/**
365 * key_hash - get directory entry hash.
366 * @c: UBIFS file-system description object
367 * @key: the key to get hash from
368 */
369static inline uint32_t key_hash(const struct ubifs_info *c,
370 const union ubifs_key *key)
371{
372 return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
373}
374
375/**
376 * key_hash_flash - get directory entry hash from an on-flash formatted key.
377 * @c: UBIFS file-system description object
378 * @k: the key to get hash from
379 */
380static inline uint32_t key_hash_flash(const struct ubifs_info *c, const void *k)
381{
382 const union ubifs_key *key = k;
383
384 return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
385}
386
387/**
388 * key_block - get data block number.
389 * @c: UBIFS file-system description object
390 * @key: the key to get the block number from
391 */
392static inline unsigned int key_block(const struct ubifs_info *c,
393 const union ubifs_key *key)
394{
395 return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
396}
397
398/**
399 * key_block_flash - get data block number from an on-flash formatted key.
400 * @c: UBIFS file-system description object
401 * @k: the key to get the block number from
402 */
403static inline unsigned int key_block_flash(const struct ubifs_info *c,
404 const void *k)
405{
406 const union ubifs_key *key = k;
407
408 return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK;
409}
410
411/**
412 * key_read - transform a key to in-memory format.
413 * @c: UBIFS file-system description object
414 * @from: the key to transform
415 * @to: the key to store the result
416 */
417static inline void key_read(const struct ubifs_info *c, const void *from,
418 union ubifs_key *to)
419{
420 const union ubifs_key *f = from;
421
422 to->u32[0] = le32_to_cpu(f->j32[0]);
423 to->u32[1] = le32_to_cpu(f->j32[1]);
424}
425
426/**
427 * key_write - transform a key from in-memory format.
428 * @c: UBIFS file-system description object
429 * @from: the key to transform
430 * @to: the key to store the result
431 */
432static inline void key_write(const struct ubifs_info *c,
433 const union ubifs_key *from, void *to)
434{
435 union ubifs_key *t = to;
436
437 t->j32[0] = cpu_to_le32(from->u32[0]);
438 t->j32[1] = cpu_to_le32(from->u32[1]);
439 memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
440}
441
442/**
443 * key_write_idx - transform a key from in-memory format for the index.
444 * @c: UBIFS file-system description object
445 * @from: the key to transform
446 * @to: the key to store the result
447 */
448static inline void key_write_idx(const struct ubifs_info *c,
449 const union ubifs_key *from, void *to)
450{
451 union ubifs_key *t = to;
452
453 t->j32[0] = cpu_to_le32(from->u32[0]);
454 t->j32[1] = cpu_to_le32(from->u32[1]);
455}
456
457/**
458 * key_copy - copy a key.
459 * @c: UBIFS file-system description object
460 * @from: the key to copy from
461 * @to: the key to copy to
462 */
463static inline void key_copy(const struct ubifs_info *c,
464 const union ubifs_key *from, union ubifs_key *to)
465{
466 to->u64[0] = from->u64[0];
467}
468
469/**
470 * keys_cmp - compare keys.
471 * @c: UBIFS file-system description object
472 * @key1: the first key to compare
473 * @key2: the second key to compare
474 *
475 * This function compares 2 keys and returns %-1 if @key1 is less than
476 * @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2.
477 */
478static inline int keys_cmp(const struct ubifs_info *c,
479 const union ubifs_key *key1,
480 const union ubifs_key *key2)
481{
482 if (key1->u32[0] < key2->u32[0])
483 return -1;
484 if (key1->u32[0] > key2->u32[0])
485 return 1;
486 if (key1->u32[1] < key2->u32[1])
487 return -1;
488 if (key1->u32[1] > key2->u32[1])
489 return 1;
490
491 return 0;
492}
493
494/**
495 * keys_eq - determine if keys are equivalent.
496 * @c: UBIFS file-system description object
497 * @key1: the first key to compare
498 * @key2: the second key to compare
499 *
500 * This function compares 2 keys and returns %1 if @key1 is equal to @key2 and
501 * %0 if not.
502 */
503static inline int keys_eq(const struct ubifs_info *c,
504 const union ubifs_key *key1,
505 const union ubifs_key *key2)
506{
507 if (key1->u32[0] != key2->u32[0])
508 return 0;
509 if (key1->u32[1] != key2->u32[1])
510 return 0;
511 return 1;
512}
513
514/**
515 * is_hash_key - is a key vulnerable to hash collisions.
516 * @c: UBIFS file-system description object
517 * @key: key
518 *
519 * This function returns %1 if @key is a hashed key or %0 otherwise.
520 */
521static inline int is_hash_key(const struct ubifs_info *c,
522 const union ubifs_key *key)
523{
524 int type = key_type(c, key);
525
526 return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY;
527}
528
529/**
530 * key_max_inode_size - get maximum file size allowed by current key format.
531 * @c: UBIFS file-system description object
532 */
533static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
534{
535 switch (c->key_fmt) {
536 case UBIFS_SIMPLE_KEY_FMT:
537 return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
538 default:
539 return 0;
540 }
541}
542
543#endif /* !__UBIFS_KEY_H__ */