[linux-2.6-block.git] / security / selinux / ss / ebitmap.h

/*
 * An extensible bitmap is a bitmap that supports an
 * arbitrary number of bits.  Extensible bitmaps are
 * used to represent sets of values, such as types,
 * roles, categories, and classes.
 *
 * Each extensible bitmap is implemented as a linked
 * list of bitmap nodes, where each bitmap node has
 * an explicitly specified starting bit position within
 * the total bitmap.
 *
 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
 */
#ifndef _SS_EBITMAP_H_
#define _SS_EBITMAP_H_

#include <net/netlabel.h>

#define EBITMAP_UNIT_NUMS	((32 - sizeof(void *) - sizeof(u32))	\
					/ sizeof(unsigned long))
#define EBITMAP_UNIT_SIZE	BITS_PER_LONG
#define EBITMAP_SIZE		(EBITMAP_UNIT_NUMS * EBITMAP_UNIT_SIZE)
#define EBITMAP_BIT		1ULL
#define EBITMAP_SHIFT_UNIT_SIZE(x)					\
	(((x) >> EBITMAP_UNIT_SIZE / 2) >> EBITMAP_UNIT_SIZE / 2)

struct ebitmap_node {
	struct ebitmap_node *next;
	unsigned long maps[EBITMAP_UNIT_NUMS];
	u32 startbit;
};

struct ebitmap {
	struct ebitmap_node *node;	/* first node in the bitmap */
	u32 highbit;	/* highest position in the total bitmap */
};

#define ebitmap_length(e) ((e)->highbit)
#define ebitmap_startbit(e) ((e)->node ? (e)->node->startbit : 0)

static inline unsigned int ebitmap_start_positive(struct ebitmap *e,
						  struct ebitmap_node **n)
{
	unsigned int ofs;

	for (*n = e->node; *n; *n = (*n)->next) {
		ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
		if (ofs < EBITMAP_SIZE)
			return (*n)->startbit + ofs;
	}
	return ebitmap_length(e);
}

static inline void ebitmap_init(struct ebitmap *e)
{
	memset(e, 0, sizeof(*e));
}

static inline unsigned int ebitmap_next_positive(struct ebitmap *e,
						 struct ebitmap_node **n,
						 unsigned int bit)
{
	unsigned int ofs;

	ofs = find_next_bit((*n)->maps, EBITMAP_SIZE, bit - (*n)->startbit + 1);
	if (ofs < EBITMAP_SIZE)
		return ofs + (*n)->startbit;

	for (*n = (*n)->next; *n; *n = (*n)->next) {
		ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
		if (ofs < EBITMAP_SIZE)
			return ofs + (*n)->startbit;
	}
	return ebitmap_length(e);
}

#define EBITMAP_NODE_INDEX(node, bit)	\
	(((bit) - (node)->startbit) / EBITMAP_UNIT_SIZE)
#define EBITMAP_NODE_OFFSET(node, bit)	\
	(((bit) - (node)->startbit) % EBITMAP_UNIT_SIZE)

static inline int ebitmap_node_get_bit(struct ebitmap_node *n,
				       unsigned int bit)
{
	unsigned int index = EBITMAP_NODE_INDEX(n, bit);
	unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);

	BUG_ON(index >= EBITMAP_UNIT_NUMS);
	if ((n->maps[index] & (EBITMAP_BIT << ofs)))
		return 1;
	return 0;
}

static inline void ebitmap_node_set_bit(struct ebitmap_node *n,
					unsigned int bit)
{
	unsigned int index = EBITMAP_NODE_INDEX(n, bit);
	unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);

	BUG_ON(index >= EBITMAP_UNIT_NUMS);
	n->maps[index] |= (EBITMAP_BIT << ofs);
}

static inline void ebitmap_node_clr_bit(struct ebitmap_node *n,
					unsigned int bit)
{
	unsigned int index = EBITMAP_NODE_INDEX(n, bit);
	unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);

	BUG_ON(index >= EBITMAP_UNIT_NUMS);
	n->maps[index] &= ~(EBITMAP_BIT << ofs);
}

#define ebitmap_for_each_positive_bit(e, n, bit)	\
	for (bit = ebitmap_start_positive(e, &n);	\
	     bit < ebitmap_length(e);			\
	     bit = ebitmap_next_positive(e, &n, bit))	\

int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2);
int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src);
int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2);
int ebitmap_get_bit(struct ebitmap *e, unsigned long bit);
int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value);
void ebitmap_destroy(struct ebitmap *e);
int ebitmap_read(struct ebitmap *e, void *fp);

#ifdef CONFIG_NETLABEL
int ebitmap_netlbl_export(struct ebitmap *ebmap,
			  struct netlbl_lsm_secattr_catmap **catmap);
int ebitmap_netlbl_import(struct ebitmap *ebmap,
			  struct netlbl_lsm_secattr_catmap *catmap);
#else
static inline int ebitmap_netlbl_export(struct ebitmap *ebmap,
				struct netlbl_lsm_secattr_catmap **catmap)
{
	return -ENOMEM;
}
static inline int ebitmap_netlbl_import(struct ebitmap *ebmap,
				struct netlbl_lsm_secattr_catmap *catmap)
{
	return -ENOMEM;
}
#endif

#endif	/* _SS_EBITMAP_H_ */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* An extensible bitmap is a bitmap that supports an
	3	* arbitrary number of bits. Extensible bitmaps are
	4	* used to represent sets of values, such as types,
	5	* roles, categories, and classes.
	6	*
	7	* Each extensible bitmap is implemented as a linked
	8	* list of bitmap nodes, where each bitmap node has
	9	* an explicitly specified starting bit position within
	10	* the total bitmap.
	11	*
	12	* Author : Stephen Smalley, <sds@epoch.ncsc.mil>
	13	*/
	14	#ifndef _SS_EBITMAP_H_
	15	#define _SS_EBITMAP_H_
	16
02752760 PM	17	#include <net/netlabel.h>
02752760 PM	18
9fe79ad1 KK	19	#define EBITMAP_UNIT_NUMS ((32 - sizeof(void *) - sizeof(u32)) \
	20	/ sizeof(unsigned long))
	21	#define EBITMAP_UNIT_SIZE BITS_PER_LONG
	22	#define EBITMAP_SIZE (EBITMAP_UNIT_NUMS * EBITMAP_UNIT_SIZE)
	23	#define EBITMAP_BIT 1ULL
087feb98 KK	24	#define EBITMAP_SHIFT_UNIT_SIZE(x) \
087feb98 KK	25	(((x) >> EBITMAP_UNIT_SIZE / 2) >> EBITMAP_UNIT_SIZE / 2)
1da177e4 LT	26
1da177e4 LT	27	struct ebitmap_node {
1da177e4	28	struct ebitmap_node *next;
9fe79ad1 KK	29	unsigned long maps[EBITMAP_UNIT_NUMS];
9fe79ad1 KK	30	u32 startbit;
1da177e4 LT	31	};
	32
	33	struct ebitmap {
	34	struct ebitmap_node node; / first node in the bitmap */
	35	u32 highbit; /* highest position in the total bitmap */
	36	};
	37
	38	#define ebitmap_length(e) ((e)->highbit)
	39	#define ebitmap_startbit(e) ((e)->node ? (e)->node->startbit : 0)
	40
9fe79ad1 KK	41	static inline unsigned int ebitmap_start_positive(struct ebitmap *e,
9fe79ad1 KK	42	struct ebitmap_node **n)
782ebb99	43	{
9fe79ad1 KK	44	unsigned int ofs;
	45
	46	for (n = e->node; n; n = (n)->next) {
	47	ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
	48	if (ofs < EBITMAP_SIZE)
	49	return (*n)->startbit + ofs;
	50	}
	51	return ebitmap_length(e);
782ebb99 SS	52	}
782ebb99 SS	53
1da177e4 LT	54	static inline void ebitmap_init(struct ebitmap *e)
	55	{
	56	memset(e, 0, sizeof(*e));
	57	}
	58
9fe79ad1 KK	59	static inline unsigned int ebitmap_next_positive(struct ebitmap *e,
	60	struct ebitmap_node **n,
	61	unsigned int bit)
782ebb99	62	{
9fe79ad1 KK	63	unsigned int ofs;
	64
	65	ofs = find_next_bit((n)->maps, EBITMAP_SIZE, bit - (n)->startbit + 1);
	66	if (ofs < EBITMAP_SIZE)
	67	return ofs + (*n)->startbit;
782ebb99	68
9fe79ad1 KK	69	for (n = (n)->next; n; n = (*n)->next) {
	70	ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
	71	if (ofs < EBITMAP_SIZE)
	72	return ofs + (*n)->startbit;
	73	}
	74	return ebitmap_length(e);
782ebb99 SS	75	}
782ebb99 SS	76
9fe79ad1 KK	77	#define EBITMAP_NODE_INDEX(node, bit) \
	78	(((bit) - (node)->startbit) / EBITMAP_UNIT_SIZE)
	79	#define EBITMAP_NODE_OFFSET(node, bit) \
	80	(((bit) - (node)->startbit) % EBITMAP_UNIT_SIZE)
	81
	82	static inline int ebitmap_node_get_bit(struct ebitmap_node *n,
782ebb99 SS	83	unsigned int bit)
782ebb99 SS	84	{
9fe79ad1 KK	85	unsigned int index = EBITMAP_NODE_INDEX(n, bit);
	86	unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);
	87
	88	BUG_ON(index >= EBITMAP_UNIT_NUMS);
	89	if ((n->maps[index] & (EBITMAP_BIT << ofs)))
782ebb99 SS	90	return 1;
	91	return 0;
	92	}
	93
9fe79ad1 KK	94	static inline void ebitmap_node_set_bit(struct ebitmap_node *n,
	95	unsigned int bit)
	96	{
	97	unsigned int index = EBITMAP_NODE_INDEX(n, bit);
	98	unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);
	99
	100	BUG_ON(index >= EBITMAP_UNIT_NUMS);
	101	n->maps[index] \|= (EBITMAP_BIT << ofs);
	102	}
	103
	104	static inline void ebitmap_node_clr_bit(struct ebitmap_node *n,
	105	unsigned int bit)
	106	{
	107	unsigned int index = EBITMAP_NODE_INDEX(n, bit);
	108	unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);
	109
	110	BUG_ON(index >= EBITMAP_UNIT_NUMS);
	111	n->maps[index] &= ~(EBITMAP_BIT << ofs);
	112	}
	113
	114	#define ebitmap_for_each_positive_bit(e, n, bit) \
	115	for (bit = ebitmap_start_positive(e, &n); \
	116	bit < ebitmap_length(e); \
	117	bit = ebitmap_next_positive(e, &n, bit)) \
782ebb99	118
1da177e4 LT	119	int ebitmap_cmp(struct ebitmap e1, struct ebitmap e2);
	120	int ebitmap_cpy(struct ebitmap dst, struct ebitmap src);
	121	int ebitmap_contains(struct ebitmap e1, struct ebitmap e2);
	122	int ebitmap_get_bit(struct ebitmap *e, unsigned long bit);
	123	int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value);
	124	void ebitmap_destroy(struct ebitmap *e);
	125	int ebitmap_read(struct ebitmap e, void fp);
	126
02752760 PM	127	#ifdef CONFIG_NETLABEL
	128	int ebitmap_netlbl_export(struct ebitmap *ebmap,
	129	struct netlbl_lsm_secattr_catmap **catmap);
	130	int ebitmap_netlbl_import(struct ebitmap *ebmap,
	131	struct netlbl_lsm_secattr_catmap *catmap);
	132	#else
	133	static inline int ebitmap_netlbl_export(struct ebitmap *ebmap,
	134	struct netlbl_lsm_secattr_catmap **catmap)
	135	{
	136	return -ENOMEM;
	137	}
	138	static inline int ebitmap_netlbl_import(struct ebitmap *ebmap,
	139	struct netlbl_lsm_secattr_catmap *catmap)
	140	{
	141	return -ENOMEM;
	142	}
	143	#endif
	144
1da177e4	145	#endif /* _SS_EBITMAP_H_ */