[mirror_ubuntu-eoan-kernel.git] / fs / ubifs / key.h

/*
 * This file is part of UBIFS.
 *
 * Copyright (C) 2006-2008 Nokia Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * Authors: Artem Bityutskiy (Битюцкий Артём)
 *          Adrian Hunter
 */

/*
 * This header contains various key-related definitions and helper function.
 * UBIFS allows several key schemes, so we access key fields only via these
 * helpers. At the moment only one key scheme is supported.
 *
 * Simple key scheme
 * ~~~~~~~~~~~~~~~~~
 *
 * Keys are 64-bits long. First 32-bits are inode number (parent inode number
 * in case of direntry key). Next 3 bits are node type. The last 29 bits are
 * 4KiB offset in case of inode node, and direntry hash in case of a direntry
 * node. We use "r5" hash borrowed from reiserfs.
 */

/*
 * Lot's of the key helpers require a struct ubifs_info *c as the first parameter.
 * But we are not using it at all currently. That's designed for future extensions of
 * different c->key_format. But right now, there is only one key type, UBIFS_SIMPLE_KEY_FMT.
 */

#ifndef __UBIFS_KEY_H__
#define __UBIFS_KEY_H__

/**
 * key_mask_hash - mask a valid hash value.
 * @val: value to be masked
 *
 * We use hash values as offset in directories, so values %0 and %1 are
 * reserved for "." and "..". %2 is reserved for "end of readdir" marker. This
 * function makes sure the reserved values are not used.
 */
static inline uint32_t key_mask_hash(uint32_t hash)
{
	hash &= UBIFS_S_KEY_HASH_MASK;
	if (unlikely(hash <= 2))
		hash += 3;
	return hash;
}

/**
 * key_r5_hash - R5 hash function (borrowed from reiserfs).
 * @s: direntry name
 * @len: name length
 */
static inline uint32_t key_r5_hash(const char *s, int len)
{
	uint32_t a = 0;
	const signed char *str = (const signed char *)s;

	while (len--) {
		a += *str << 4;
		a += *str >> 4;
		a *= 11;
		str++;
	}

	return key_mask_hash(a);
}

/**
 * key_test_hash - testing hash function.
 * @str: direntry name
 * @len: name length
 */
static inline uint32_t key_test_hash(const char *str, int len)
{
	uint32_t a = 0;

	len = min_t(uint32_t, len, 4);
	memcpy(&a, str, len);
	return key_mask_hash(a);
}

/**
 * ino_key_init - initialize inode key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: inode number
 */
static inline void ino_key_init(const struct ubifs_info *c,
				union ubifs_key *key, ino_t inum)
{
	key->u32[0] = inum;
	key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
}

/**
 * ino_key_init_flash - initialize on-flash inode key.
 * @c: UBIFS file-system description object
 * @k: key to initialize
 * @inum: inode number
 */
static inline void ino_key_init_flash(const struct ubifs_info *c, void *k,
				      ino_t inum)
{
	union ubifs_key *key = k;

	key->j32[0] = cpu_to_le32(inum);
	key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
}

/**
 * lowest_ino_key - get the lowest possible inode key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: inode number
 */
static inline void lowest_ino_key(const struct ubifs_info *c,
				union ubifs_key *key, ino_t inum)
{
	key->u32[0] = inum;
	key->u32[1] = 0;
}

/**
 * highest_ino_key - get the highest possible inode key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: inode number
 */
static inline void highest_ino_key(const struct ubifs_info *c,
				union ubifs_key *key, ino_t inum)
{
	key->u32[0] = inum;
	key->u32[1] = 0xffffffff;
}

/**
 * dent_key_init - initialize directory entry key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: parent inode number
 * @nm: direntry name and length. Not a string when encrypted!
 */
static inline void dent_key_init(const struct ubifs_info *c,
				 union ubifs_key *key, ino_t inum,
				 const struct fscrypt_name *nm)
{
	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));

	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
	ubifs_assert(c, !nm->hash && !nm->minor_hash);
	key->u32[0] = inum;
	key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
}

/**
 * dent_key_init_hash - initialize directory entry key without re-calculating
 *                      hash function.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: parent inode number
 * @hash: direntry name hash
 */
static inline void dent_key_init_hash(const struct ubifs_info *c,
				      union ubifs_key *key, ino_t inum,
				      uint32_t hash)
{
	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
	key->u32[0] = inum;
	key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
}

/**
 * dent_key_init_flash - initialize on-flash directory entry key.
 * @c: UBIFS file-system description object
 * @k: key to initialize
 * @inum: parent inode number
 * @nm: direntry name and length
 */
static inline void dent_key_init_flash(const struct ubifs_info *c, void *k,
				       ino_t inum,
				       const struct fscrypt_name *nm)
{
	union ubifs_key *key = k;
	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));

	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
	key->j32[0] = cpu_to_le32(inum);
	key->j32[1] = cpu_to_le32(hash |
				  (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
}

/**
 * lowest_dent_key - get the lowest possible directory entry key.
 * @c: UBIFS file-system description object
 * @key: where to store the lowest key
 * @inum: parent inode number
 */
static inline void lowest_dent_key(const struct ubifs_info *c,
				   union ubifs_key *key, ino_t inum)
{
	key->u32[0] = inum;
	key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
}

/**
 * xent_key_init - initialize extended attribute entry key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: host inode number
 * @nm: extended attribute entry name and length
 */
static inline void xent_key_init(const struct ubifs_info *c,
				 union ubifs_key *key, ino_t inum,
				 const struct fscrypt_name *nm)
{
	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));

	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
	key->u32[0] = inum;
	key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
}

/**
 * xent_key_init_flash - initialize on-flash extended attribute entry key.
 * @c: UBIFS file-system description object
 * @k: key to initialize
 * @inum: host inode number
 * @nm: extended attribute entry name and length
 */
static inline void xent_key_init_flash(const struct ubifs_info *c, void *k,
				       ino_t inum, const struct fscrypt_name *nm)
{
	union ubifs_key *key = k;
	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));

	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
	key->j32[0] = cpu_to_le32(inum);
	key->j32[1] = cpu_to_le32(hash |
				  (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
}

/**
 * lowest_xent_key - get the lowest possible extended attribute entry key.
 * @c: UBIFS file-system description object
 * @key: where to store the lowest key
 * @inum: host inode number
 */
static inline void lowest_xent_key(const struct ubifs_info *c,
				   union ubifs_key *key, ino_t inum)
{
	key->u32[0] = inum;
	key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
}

/**
 * data_key_init - initialize data key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: inode number
 * @block: block number
 */
static inline void data_key_init(const struct ubifs_info *c,
				 union ubifs_key *key, ino_t inum,
				 unsigned int block)
{
	ubifs_assert(c, !(block & ~UBIFS_S_KEY_BLOCK_MASK));
	key->u32[0] = inum;
	key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
}

/**
 * highest_data_key - get the highest possible data key for an inode.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: inode number
 */
static inline void highest_data_key(const struct ubifs_info *c,
				   union ubifs_key *key, ino_t inum)
{
	data_key_init(c, key, inum, UBIFS_S_KEY_BLOCK_MASK);
}

/**
 * trun_key_init - initialize truncation node key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 * @inum: inode number
 *
 * Note, UBIFS does not have truncation keys on the media and this function is
 * only used for purposes of replay.
 */
static inline void trun_key_init(const struct ubifs_info *c,
				 union ubifs_key *key, ino_t inum)
{
	key->u32[0] = inum;
	key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
}

/**
 * invalid_key_init - initialize invalid node key.
 * @c: UBIFS file-system description object
 * @key: key to initialize
 *
 * This is a helper function which marks a @key object as invalid.
 */
static inline void invalid_key_init(const struct ubifs_info *c,
				    union ubifs_key *key)
{
	key->u32[0] = 0xDEADBEAF;
	key->u32[1] = UBIFS_INVALID_KEY;
}

/**
 * key_type - get key type.
 * @c: UBIFS file-system description object
 * @key: key to get type of
 */
static inline int key_type(const struct ubifs_info *c,
			   const union ubifs_key *key)
{
	return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
}

/**
 * key_type_flash - get type of a on-flash formatted key.
 * @c: UBIFS file-system description object
 * @k: key to get type of
 */
static inline int key_type_flash(const struct ubifs_info *c, const void *k)
{
	const union ubifs_key *key = k;

	return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
}

/**
 * key_inum - fetch inode number from key.
 * @c: UBIFS file-system description object
 * @k: key to fetch inode number from
 */
static inline ino_t key_inum(const struct ubifs_info *c, const void *k)
{
	const union ubifs_key *key = k;

	return key->u32[0];
}

/**
 * key_inum_flash - fetch inode number from an on-flash formatted key.
 * @c: UBIFS file-system description object
 * @k: key to fetch inode number from
 */
static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k)
{
	const union ubifs_key *key = k;

	return le32_to_cpu(key->j32[0]);
}

/**
 * key_hash - get directory entry hash.
 * @c: UBIFS file-system description object
 * @key: the key to get hash from
 */
static inline uint32_t key_hash(const struct ubifs_info *c,
				const union ubifs_key *key)
{
	return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
}

/**
 * key_hash_flash - get directory entry hash from an on-flash formatted key.
 * @c: UBIFS file-system description object
 * @k: the key to get hash from
 */
static inline uint32_t key_hash_flash(const struct ubifs_info *c, const void *k)
{
	const union ubifs_key *key = k;

	return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
}

/**
 * key_block - get data block number.
 * @c: UBIFS file-system description object
 * @key: the key to get the block number from
 */
static inline unsigned int key_block(const struct ubifs_info *c,
				     const union ubifs_key *key)
{
	return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
}

/**
 * key_block_flash - get data block number from an on-flash formatted key.
 * @c: UBIFS file-system description object
 * @k: the key to get the block number from
 */
static inline unsigned int key_block_flash(const struct ubifs_info *c,
					   const void *k)
{
	const union ubifs_key *key = k;

	return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK;
}

/**
 * key_read - transform a key to in-memory format.
 * @c: UBIFS file-system description object
 * @from: the key to transform
 * @to: the key to store the result
 */
static inline void key_read(const struct ubifs_info *c, const void *from,
			    union ubifs_key *to)
{
	const union ubifs_key *f = from;

	to->u32[0] = le32_to_cpu(f->j32[0]);
	to->u32[1] = le32_to_cpu(f->j32[1]);
}

/**
 * key_write - transform a key from in-memory format.
 * @c: UBIFS file-system description object
 * @from: the key to transform
 * @to: the key to store the result
 */
static inline void key_write(const struct ubifs_info *c,
			     const union ubifs_key *from, void *to)
{
	union ubifs_key *t = to;

	t->j32[0] = cpu_to_le32(from->u32[0]);
	t->j32[1] = cpu_to_le32(from->u32[1]);
	memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
}

/**
 * key_write_idx - transform a key from in-memory format for the index.
 * @c: UBIFS file-system description object
 * @from: the key to transform
 * @to: the key to store the result
 */
static inline void key_write_idx(const struct ubifs_info *c,
				 const union ubifs_key *from, void *to)
{
	union ubifs_key *t = to;

	t->j32[0] = cpu_to_le32(from->u32[0]);
	t->j32[1] = cpu_to_le32(from->u32[1]);
}

/**
 * key_copy - copy a key.
 * @c: UBIFS file-system description object
 * @from: the key to copy from
 * @to: the key to copy to
 */
static inline void key_copy(const struct ubifs_info *c,
			    const union ubifs_key *from, union ubifs_key *to)
{
	to->u64[0] = from->u64[0];
}

/**
 * keys_cmp - compare keys.
 * @c: UBIFS file-system description object
 * @key1: the first key to compare
 * @key2: the second key to compare
 *
 * This function compares 2 keys and returns %-1 if @key1 is less than
 * @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2.
 */
static inline int keys_cmp(const struct ubifs_info *c,
			   const union ubifs_key *key1,
			   const union ubifs_key *key2)
{
	if (key1->u32[0] < key2->u32[0])
		return -1;
	if (key1->u32[0] > key2->u32[0])
		return 1;
	if (key1->u32[1] < key2->u32[1])
		return -1;
	if (key1->u32[1] > key2->u32[1])
		return 1;

	return 0;
}

/**
 * keys_eq - determine if keys are equivalent.
 * @c: UBIFS file-system description object
 * @key1: the first key to compare
 * @key2: the second key to compare
 *
 * This function compares 2 keys and returns %1 if @key1 is equal to @key2 and
 * %0 if not.
 */
static inline int keys_eq(const struct ubifs_info *c,
			  const union ubifs_key *key1,
			  const union ubifs_key *key2)
{
	if (key1->u32[0] != key2->u32[0])
		return 0;
	if (key1->u32[1] != key2->u32[1])
		return 0;
	return 1;
}

/**
 * is_hash_key - is a key vulnerable to hash collisions.
 * @c: UBIFS file-system description object
 * @key: key
 *
 * This function returns %1 if @key is a hashed key or %0 otherwise.
 */
static inline int is_hash_key(const struct ubifs_info *c,
			      const union ubifs_key *key)
{
	int type = key_type(c, key);

	return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY;
}

/**
 * key_max_inode_size - get maximum file size allowed by current key format.
 * @c: UBIFS file-system description object
 */
static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
{
	switch (c->key_fmt) {
	case UBIFS_SIMPLE_KEY_FMT:
		return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
	default:
		return 0;
	}
}

#endif /* !__UBIFS_KEY_H__ */
Commit	Line	Data
1e51764a AB	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
170eb55f DY	37	/*
	38	* Lot's of the key helpers require a struct ubifs_info *c as the first parameter.
	39	* But we are not using it at all currently. That's designed for future extensions of
	40	* different c->key_format. But right now, there is only one key type, UBIFS_SIMPLE_KEY_FMT.
	41	*/
	42
1e51764a AB	43	#ifndef __UBIFS_KEY_H__
	44	#define __UBIFS_KEY_H__
	45
5dd7cbc0 KM	46	/**
	47	* key_mask_hash - mask a valid hash value.
	48	* @val: value to be masked
	49	*
	50	* We use hash values as offset in directories, so values %0 and %1 are
	51	* reserved for "." and "..". %2 is reserved for "end of readdir" marker. This
	52	* function makes sure the reserved values are not used.
	53	*/
	54	static inline uint32_t key_mask_hash(uint32_t hash)
	55	{
	56	hash &= UBIFS_S_KEY_HASH_MASK;
	57	if (unlikely(hash <= 2))
	58	hash += 3;
	59	return hash;
	60	}
	61
1e51764a AB	62	/**
	63	* key_r5_hash - R5 hash function (borrowed from reiserfs).
	64	* @s: direntry name
	65	* @len: name length
	66	*/
	67	static inline uint32_t key_r5_hash(const char *s, int len)
	68	{
	69	uint32_t a = 0;
	70	const signed char str = (const signed char )s;
	71
b9bc8c7b	72	while (len--) {
1e51764a AB	73	a += *str << 4;
	74	a += *str >> 4;
	75	a *= 11;
	76	str++;
	77	}
	78
5dd7cbc0	79	return key_mask_hash(a);
1e51764a AB	80	}
	81
	82	/**
	83	* key_test_hash - testing hash function.
	84	* @str: direntry name
	85	* @len: name length
	86	*/
	87	static inline uint32_t key_test_hash(const char *str, int len)
	88	{
	89	uint32_t a = 0;
	90
	91	len = min_t(uint32_t, len, 4);
	92	memcpy(&a, str, len);
5dd7cbc0	93	return key_mask_hash(a);
1e51764a AB	94	}
	95
	96	/**
	97	* ino_key_init - initialize inode key.
	98	* @c: UBIFS file-system description object
	99	* @key: key to initialize
	100	* @inum: inode number
	101	*/
	102	static inline void ino_key_init(const struct ubifs_info *c,
	103	union ubifs_key *key, ino_t inum)
	104	{
	105	key->u32[0] = inum;
	106	key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
	107	}
	108
	109	/**
	110	* ino_key_init_flash - initialize on-flash inode key.
	111	* @c: UBIFS file-system description object
	112	* @k: key to initialize
	113	* @inum: inode number
	114	*/
	115	static inline void ino_key_init_flash(const struct ubifs_info c, void k,
	116	ino_t inum)
	117	{
	118	union ubifs_key *key = k;
	119
	120	key->j32[0] = cpu_to_le32(inum);
	121	key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
	122	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
	123	}
	124
	125	/**
	126	* lowest_ino_key - get the lowest possible inode key.
	127	* @c: UBIFS file-system description object
	128	* @key: key to initialize
	129	* @inum: inode number
	130	*/
	131	static inline void lowest_ino_key(const struct ubifs_info *c,
	132	union ubifs_key *key, ino_t inum)
	133	{
	134	key->u32[0] = inum;
	135	key->u32[1] = 0;
	136	}
	137
	138	/**
	139	* highest_ino_key - get the highest possible inode key.
	140	* @c: UBIFS file-system description object
	141	* @key: key to initialize
	142	* @inum: inode number
	143	*/
	144	static inline void highest_ino_key(const struct ubifs_info *c,
	145	union ubifs_key *key, ino_t inum)
	146	{
	147	key->u32[0] = inum;
	148	key->u32[1] = 0xffffffff;
	149	}
	150
	151	/**
	152	* dent_key_init - initialize directory entry key.
	153	* @c: UBIFS file-system description object
	154	* @key: key to initialize
	155	* @inum: parent inode number
f4f61d2c	156	* @nm: direntry name and length. Not a string when encrypted!
1e51764a AB	157	*/
	158	static inline void dent_key_init(const struct ubifs_info *c,
	159	union ubifs_key *key, ino_t inum,
f4f61d2c	160	const struct fscrypt_name *nm)
1e51764a	161	{
f4f61d2c	162	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
1e51764a	163
6eb61d58 RW	164	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
6eb61d58 RW	165	ubifs_assert(c, !nm->hash && !nm->minor_hash);
1e51764a AB	166	key->u32[0] = inum;
	167	key->u32[1] = hash \| (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
	168	}
	169
	170	/**
	171	* dent_key_init_hash - initialize directory entry key without re-calculating
	172	* hash function.
	173	* @c: UBIFS file-system description object
	174	* @key: key to initialize
	175	* @inum: parent inode number
	176	* @hash: direntry name hash
	177	*/
	178	static inline void dent_key_init_hash(const struct ubifs_info *c,
	179	union ubifs_key *key, ino_t inum,
	180	uint32_t hash)
	181	{
6eb61d58	182	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
1e51764a AB	183	key->u32[0] = inum;
	184	key->u32[1] = hash \| (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
	185	}
	186
	187	/**
	188	* dent_key_init_flash - initialize on-flash directory entry key.
	189	* @c: UBIFS file-system description object
	190	* @k: key to initialize
	191	* @inum: parent inode number
	192	* @nm: direntry name and length
	193	*/
	194	static inline void dent_key_init_flash(const struct ubifs_info c, void k,
f4f61d2c RW	195	ino_t inum,
f4f61d2c RW	196	const struct fscrypt_name *nm)
1e51764a AB	197	{
1e51764a AB	198	union ubifs_key *key = k;
f4f61d2c	199	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
1e51764a	200
6eb61d58	201	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
1e51764a AB	202	key->j32[0] = cpu_to_le32(inum);
	203	key->j32[1] = cpu_to_le32(hash \|
	204	(UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
	205	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
	206	}
	207
	208	/**
	209	* lowest_dent_key - get the lowest possible directory entry key.
	210	* @c: UBIFS file-system description object
	211	* @key: where to store the lowest key
	212	* @inum: parent inode number
	213	*/
	214	static inline void lowest_dent_key(const struct ubifs_info *c,
	215	union ubifs_key *key, ino_t inum)
	216	{
	217	key->u32[0] = inum;
	218	key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
	219	}
	220
	221	/**
	222	* xent_key_init - initialize extended attribute entry key.
	223	* @c: UBIFS file-system description object
	224	* @key: key to initialize
	225	* @inum: host inode number
	226	* @nm: extended attribute entry name and length
	227	*/
	228	static inline void xent_key_init(const struct ubifs_info *c,
	229	union ubifs_key *key, ino_t inum,
f4f61d2c	230	const struct fscrypt_name *nm)
1e51764a	231	{
f4f61d2c	232	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
1e51764a	233
6eb61d58	234	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
1e51764a AB	235	key->u32[0] = inum;
	236	key->u32[1] = hash \| (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
	237	}
	238
1e51764a AB	239	/**
	240	* xent_key_init_flash - initialize on-flash extended attribute entry key.
	241	* @c: UBIFS file-system description object
	242	* @k: key to initialize
	243	* @inum: host inode number
	244	* @nm: extended attribute entry name and length
	245	*/
	246	static inline void xent_key_init_flash(const struct ubifs_info c, void k,
f4f61d2c	247	ino_t inum, const struct fscrypt_name *nm)
1e51764a AB	248	{
1e51764a AB	249	union ubifs_key *key = k;
f4f61d2c	250	uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm));
1e51764a	251
6eb61d58	252	ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK));
1e51764a AB	253	key->j32[0] = cpu_to_le32(inum);
	254	key->j32[1] = cpu_to_le32(hash \|
	255	(UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
	256	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
	257	}
	258
	259	/**
	260	* lowest_xent_key - get the lowest possible extended attribute entry key.
	261	* @c: UBIFS file-system description object
	262	* @key: where to store the lowest key
	263	* @inum: host inode number
	264	*/
	265	static inline void lowest_xent_key(const struct ubifs_info *c,
	266	union ubifs_key *key, ino_t inum)
	267	{
	268	key->u32[0] = inum;
	269	key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
	270	}
	271
	272	/**
	273	* data_key_init - initialize data key.
	274	* @c: UBIFS file-system description object
	275	* @key: key to initialize
	276	* @inum: inode number
	277	* @block: block number
	278	*/
	279	static inline void data_key_init(const struct ubifs_info *c,
	280	union ubifs_key *key, ino_t inum,
	281	unsigned int block)
	282	{
6eb61d58	283	ubifs_assert(c, !(block & ~UBIFS_S_KEY_BLOCK_MASK));
1e51764a AB	284	key->u32[0] = inum;
	285	key->u32[1] = block \| (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
	286	}
	287
e3c3efc2 AB	288	/**
	289	* highest_data_key - get the highest possible data key for an inode.
	290	* @c: UBIFS file-system description object
	291	* @key: key to initialize
	292	* @inum: inode number
	293	*/
	294	static inline void highest_data_key(const struct ubifs_info *c,
	295	union ubifs_key *key, ino_t inum)
	296	{
	297	data_key_init(c, key, inum, UBIFS_S_KEY_BLOCK_MASK);
	298	}
	299
1e51764a AB	300	/**
	301	* trun_key_init - initialize truncation node key.
	302	* @c: UBIFS file-system description object
	303	* @key: key to initialize
	304	* @inum: inode number
	305	*
	306	* Note, UBIFS does not have truncation keys on the media and this function is
	307	* only used for purposes of replay.
	308	*/
	309	static inline void trun_key_init(const struct ubifs_info *c,
	310	union ubifs_key *key, ino_t inum)
	311	{
	312	key->u32[0] = inum;
	313	key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
	314	}
	315
ba2f48f7 AB	316	/**
	317	* invalid_key_init - initialize invalid node key.
	318	* @c: UBIFS file-system description object
	319	* @key: key to initialize
	320	*
	321	* This is a helper function which marks a @key object as invalid.
	322	*/
	323	static inline void invalid_key_init(const struct ubifs_info *c,
	324	union ubifs_key *key)
	325	{
	326	key->u32[0] = 0xDEADBEAF;
	327	key->u32[1] = UBIFS_INVALID_KEY;
	328	}
	329
1e51764a AB	330	/**
	331	* key_type - get key type.
	332	* @c: UBIFS file-system description object
	333	* @key: key to get type of
	334	*/
	335	static inline int key_type(const struct ubifs_info *c,
	336	const union ubifs_key *key)
	337	{
	338	return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
	339	}
	340
	341	/**
	342	* key_type_flash - get type of a on-flash formatted key.
	343	* @c: UBIFS file-system description object
	344	* @k: key to get type of
	345	*/
	346	static inline int key_type_flash(const struct ubifs_info c, const void k)
	347	{
	348	const union ubifs_key *key = k;
	349
0ecb9529	350	return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
1e51764a AB	351	}
	352
	353	/**
	354	* key_inum - fetch inode number from key.
	355	* @c: UBIFS file-system description object
	356	* @k: key to fetch inode number from
	357	*/
	358	static inline ino_t key_inum(const struct ubifs_info c, const void k)
	359	{
	360	const union ubifs_key *key = k;
	361
	362	return key->u32[0];
	363	}
	364
	365	/**
	366	* key_inum_flash - fetch inode number from an on-flash formatted key.
	367	* @c: UBIFS file-system description object
	368	* @k: key to fetch inode number from
	369	*/
	370	static inline ino_t key_inum_flash(const struct ubifs_info c, const void k)
	371	{
	372	const union ubifs_key *key = k;
	373
	374	return le32_to_cpu(key->j32[0]);
	375	}
	376
	377	/**
	378	* key_hash - get directory entry hash.
	379	* @c: UBIFS file-system description object
	380	* @key: the key to get hash from
	381	*/
cb4f952d AB	382	static inline uint32_t key_hash(const struct ubifs_info *c,
cb4f952d AB	383	const union ubifs_key *key)
1e51764a AB	384	{
	385	return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
	386	}
	387
	388	/**
	389	* key_hash_flash - get directory entry hash from an on-flash formatted key.
	390	* @c: UBIFS file-system description object
	391	* @k: the key to get hash from
	392	*/
cb4f952d	393	static inline uint32_t key_hash_flash(const struct ubifs_info c, const void k)
1e51764a AB	394	{
	395	const union ubifs_key *key = k;
	396
	397	return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
	398	}
	399
	400	/**
	401	* key_block - get data block number.
	402	* @c: UBIFS file-system description object
	403	* @key: the key to get the block number from
	404	*/
	405	static inline unsigned int key_block(const struct ubifs_info *c,
	406	const union ubifs_key *key)
	407	{
	408	return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
	409	}
	410
	411	/**
	412	* key_block_flash - get data block number from an on-flash formatted key.
	413	* @c: UBIFS file-system description object
	414	* @k: the key to get the block number from
	415	*/
	416	static inline unsigned int key_block_flash(const struct ubifs_info *c,
	417	const void *k)
	418	{
	419	const union ubifs_key *key = k;
	420
0ecb9529	421	return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK;
1e51764a AB	422	}
	423
	424	/**
	425	* key_read - transform a key to in-memory format.
	426	* @c: UBIFS file-system description object
	427	* @from: the key to transform
	428	* @to: the key to store the result
	429	*/
	430	static inline void key_read(const struct ubifs_info c, const void from,
	431	union ubifs_key *to)
	432	{
	433	const union ubifs_key *f = from;
	434
	435	to->u32[0] = le32_to_cpu(f->j32[0]);
	436	to->u32[1] = le32_to_cpu(f->j32[1]);
	437	}
	438
	439	/**
	440	* key_write - transform a key from in-memory format.
	441	* @c: UBIFS file-system description object
	442	* @from: the key to transform
	443	* @to: the key to store the result
	444	*/
	445	static inline void key_write(const struct ubifs_info *c,
	446	const union ubifs_key from, void to)
	447	{
	448	union ubifs_key *t = to;
	449
	450	t->j32[0] = cpu_to_le32(from->u32[0]);
	451	t->j32[1] = cpu_to_le32(from->u32[1]);
	452	memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
	453	}
	454
	455	/**
	456	* key_write_idx - transform a key from in-memory format for the index.
	457	* @c: UBIFS file-system description object
	458	* @from: the key to transform
	459	* @to: the key to store the result
	460	*/
	461	static inline void key_write_idx(const struct ubifs_info *c,
	462	const union ubifs_key from, void to)
	463	{
	464	union ubifs_key *t = to;
	465
	466	t->j32[0] = cpu_to_le32(from->u32[0]);
	467	t->j32[1] = cpu_to_le32(from->u32[1]);
	468	}
	469
	470	/**
	471	* key_copy - copy a key.
	472	* @c: UBIFS file-system description object
	473	* @from: the key to copy from
	474	* @to: the key to copy to
	475	*/
	476	static inline void key_copy(const struct ubifs_info *c,
	477	const union ubifs_key from, union ubifs_key to)
	478	{
	479	to->u64[0] = from->u64[0];
	480	}
	481
	482	/**
	483	* keys_cmp - compare keys.
	484	* @c: UBIFS file-system description object
	485	* @key1: the first key to compare
486	* @key2: the second key to compare
487	*
488	* This function compares 2 keys and returns %-1 if @key1 is less than
4793e7c5	489	* @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2.
1e51764a AB	490	*/
	491	static inline int keys_cmp(const struct ubifs_info *c,
	492	const union ubifs_key *key1,
	493	const union ubifs_key *key2)
	494	{
	495	if (key1->u32[0] < key2->u32[0])
	496	return -1;
	497	if (key1->u32[0] > key2->u32[0])
	498	return 1;
	499	if (key1->u32[1] < key2->u32[1])
	500	return -1;
	501	if (key1->u32[1] > key2->u32[1])
	502	return 1;
	503
	504	return 0;
	505	}
	506
4793e7c5 AH	507	/**
	508	* keys_eq - determine if keys are equivalent.
	509	* @c: UBIFS file-system description object
	510	* @key1: the first key to compare
	511	* @key2: the second key to compare
	512	*
	513	* This function compares 2 keys and returns %1 if @key1 is equal to @key2 and
	514	* %0 if not.
	515	*/
	516	static inline int keys_eq(const struct ubifs_info *c,
	517	const union ubifs_key *key1,
	518	const union ubifs_key *key2)
	519	{
	520	if (key1->u32[0] != key2->u32[0])
	521	return 0;
	522	if (key1->u32[1] != key2->u32[1])
	523	return 0;
	524	return 1;
	525	}
	526
1e51764a AB	527	/**
	528	* is_hash_key - is a key vulnerable to hash collisions.
	529	* @c: UBIFS file-system description object
	530	* @key: key
	531	*
	532	* This function returns %1 if @key is a hashed key or %0 otherwise.
	533	*/
	534	static inline int is_hash_key(const struct ubifs_info *c,
	535	const union ubifs_key *key)
	536	{
	537	int type = key_type(c, key);
	538
	539	return type == UBIFS_DENT_KEY \|\| type == UBIFS_XENT_KEY;
	540	}
	541
	542	/**
	543	* key_max_inode_size - get maximum file size allowed by current key format.
	544	* @c: UBIFS file-system description object
	545	*/
	546	static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
	547	{
	548	switch (c->key_fmt) {
	549	case UBIFS_SIMPLE_KEY_FMT:
	550	return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
	551	default:
	552	return 0;
	553	}
	554	}
e3c3efc2	555
1e51764a	556	#endif /* !__UBIFS_KEY_H__ */