[net-next-2.6.git] / security / selinux / ss / ebitmap.c

/*
 * Implementation of the extensible bitmap type.
 *
 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
 */
/*
 * Updated: Hewlett-Packard <paul.moore@hp.com>
 *
 *      Added support to import/export the NetLabel category bitmap
 *
 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
 */
/*
 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
 *      Applied standard bit operations to improve bitmap scanning.
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <net/netlabel.h>
#include "ebitmap.h"
#include "policydb.h"

#define BITS_PER_U64	(sizeof(u64) * 8)

int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2)
{
	struct ebitmap_node *n1, *n2;

	if (e1->highbit != e2->highbit)
		return 0;

	n1 = e1->node;
	n2 = e2->node;
	while (n1 && n2 &&
	       (n1->startbit == n2->startbit) &&
	       !memcmp(n1->maps, n2->maps, EBITMAP_SIZE / 8)) {
		n1 = n1->next;
		n2 = n2->next;
	}

	if (n1 || n2)
		return 0;

	return 1;
}

int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src)
{
	struct ebitmap_node *n, *new, *prev;

	ebitmap_init(dst);
	n = src->node;
	prev = NULL;
	while (n) {
		new = kzalloc(sizeof(*new), GFP_ATOMIC);
		if (!new) {
			ebitmap_destroy(dst);
			return -ENOMEM;
		}
		new->startbit = n->startbit;
		memcpy(new->maps, n->maps, EBITMAP_SIZE / 8);
		new->next = NULL;
		if (prev)
			prev->next = new;
		else
			dst->node = new;
		prev = new;
		n = n->next;
	}

	dst->highbit = src->highbit;
	return 0;
}

#ifdef CONFIG_NETLABEL
/**
 * ebitmap_netlbl_export - Export an ebitmap into a NetLabel category bitmap
 * @ebmap: the ebitmap to export
 * @catmap: the NetLabel category bitmap
 *
 * Description:
 * Export a SELinux extensibile bitmap into a NetLabel category bitmap.
 * Returns zero on success, negative values on error.
 *
 */
int ebitmap_netlbl_export(struct ebitmap *ebmap,
			  struct netlbl_lsm_secattr_catmap **catmap)
{
	struct ebitmap_node *e_iter = ebmap->node;
	struct netlbl_lsm_secattr_catmap *c_iter;
	u32 cmap_idx, cmap_sft;
	int i;

	/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
	 * however, it is not always compatible with an array of unsigned long
	 * in ebitmap_node.
	 * In addition, you should pay attention the following implementation
	 * assumes unsigned long has a width equal with or less than 64-bit.
	 */

	if (e_iter == NULL) {
		*catmap = NULL;
		return 0;
	}

	c_iter = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
	if (c_iter == NULL)
		return -ENOMEM;
	*catmap = c_iter;
	c_iter->startbit = e_iter->startbit & ~(NETLBL_CATMAP_SIZE - 1);

	while (e_iter) {
		for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
			unsigned int delta, e_startbit, c_endbit;

			e_startbit = e_iter->startbit + i * EBITMAP_UNIT_SIZE;
			c_endbit = c_iter->startbit + NETLBL_CATMAP_SIZE;
			if (e_startbit >= c_endbit) {
				c_iter->next
				  = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
				if (c_iter->next == NULL)
					goto netlbl_export_failure;
				c_iter = c_iter->next;
				c_iter->startbit
				  = e_startbit & ~(NETLBL_CATMAP_SIZE - 1);
			}
			delta = e_startbit - c_iter->startbit;
			cmap_idx = delta / NETLBL_CATMAP_MAPSIZE;
			cmap_sft = delta % NETLBL_CATMAP_MAPSIZE;
			c_iter->bitmap[cmap_idx]
				|= e_iter->maps[i] << cmap_sft;
		}
		e_iter = e_iter->next;
	}

	return 0;

netlbl_export_failure:
	netlbl_secattr_catmap_free(*catmap);
	return -ENOMEM;
}

/**
 * ebitmap_netlbl_import - Import a NetLabel category bitmap into an ebitmap
 * @ebmap: the ebitmap to import
 * @catmap: the NetLabel category bitmap
 *
 * Description:
 * Import a NetLabel category bitmap into a SELinux extensibile bitmap.
 * Returns zero on success, negative values on error.
 *
 */
int ebitmap_netlbl_import(struct ebitmap *ebmap,
			  struct netlbl_lsm_secattr_catmap *catmap)
{
	struct ebitmap_node *e_iter = NULL;
	struct ebitmap_node *emap_prev = NULL;
	struct netlbl_lsm_secattr_catmap *c_iter = catmap;
	u32 c_idx, c_pos, e_idx, e_sft;

	/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
	 * however, it is not always compatible with an array of unsigned long
	 * in ebitmap_node.
	 * In addition, you should pay attention the following implementation
	 * assumes unsigned long has a width equal with or less than 64-bit.
	 */

	do {
		for (c_idx = 0; c_idx < NETLBL_CATMAP_MAPCNT; c_idx++) {
			unsigned int delta;
			u64 map = c_iter->bitmap[c_idx];

			if (!map)
				continue;

			c_pos = c_iter->startbit
				+ c_idx * NETLBL_CATMAP_MAPSIZE;
			if (!e_iter
			    || c_pos >= e_iter->startbit + EBITMAP_SIZE) {
				e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);
				if (!e_iter)
					goto netlbl_import_failure;
				e_iter->startbit
					= c_pos - (c_pos % EBITMAP_SIZE);
				if (emap_prev == NULL)
					ebmap->node = e_iter;
				else
					emap_prev->next = e_iter;
				emap_prev = e_iter;
			}
			delta = c_pos - e_iter->startbit;
			e_idx = delta / EBITMAP_UNIT_SIZE;
			e_sft = delta % EBITMAP_UNIT_SIZE;
			while (map) {
				e_iter->maps[e_idx++] |= map & (-1UL);
				map = EBITMAP_SHIFT_UNIT_SIZE(map);
			}
		}
		c_iter = c_iter->next;
	} while (c_iter);
	if (e_iter != NULL)
		ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
	else
		ebitmap_destroy(ebmap);

	return 0;

netlbl_import_failure:
	ebitmap_destroy(ebmap);
	return -ENOMEM;
}
#endif /* CONFIG_NETLABEL */

int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2)
{
	struct ebitmap_node *n1, *n2;
	int i;

	if (e1->highbit < e2->highbit)
		return 0;

	n1 = e1->node;
	n2 = e2->node;
	while (n1 && n2 && (n1->startbit <= n2->startbit)) {
		if (n1->startbit < n2->startbit) {
			n1 = n1->next;
			continue;
		}
		for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
			if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
				return 0;
		}

		n1 = n1->next;
		n2 = n2->next;
	}

	if (n2)
		return 0;

	return 1;
}

int ebitmap_get_bit(struct ebitmap *e, unsigned long bit)
{
	struct ebitmap_node *n;

	if (e->highbit < bit)
		return 0;

	n = e->node;
	while (n && (n->startbit <= bit)) {
		if ((n->startbit + EBITMAP_SIZE) > bit)
			return ebitmap_node_get_bit(n, bit);
		n = n->next;
	}

	return 0;
}

int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value)
{
	struct ebitmap_node *n, *prev, *new;

	prev = NULL;
	n = e->node;
	while (n && n->startbit <= bit) {
		if ((n->startbit + EBITMAP_SIZE) > bit) {
			if (value) {
				ebitmap_node_set_bit(n, bit);
			} else {
				unsigned int s;

				ebitmap_node_clr_bit(n, bit);

				s = find_first_bit(n->maps, EBITMAP_SIZE);
				if (s < EBITMAP_SIZE)
					return 0;

				/* drop this node from the bitmap */
				if (!n->next) {
					/*
					 * this was the highest map
					 * within the bitmap
					 */
					if (prev)
						e->highbit = prev->startbit
							     + EBITMAP_SIZE;
					else
						e->highbit = 0;
				}
				if (prev)
					prev->next = n->next;
				else
					e->node = n->next;
				kfree(n);
			}
			return 0;
		}
		prev = n;
		n = n->next;
	}

	if (!value)
		return 0;

	new = kzalloc(sizeof(*new), GFP_ATOMIC);
	if (!new)
		return -ENOMEM;

	new->startbit = bit - (bit % EBITMAP_SIZE);
	ebitmap_node_set_bit(new, bit);

	if (!n)
		/* this node will be the highest map within the bitmap */
		e->highbit = new->startbit + EBITMAP_SIZE;

	if (prev) {
		new->next = prev->next;
		prev->next = new;
	} else {
		new->next = e->node;
		e->node = new;
	}

	return 0;
}

void ebitmap_destroy(struct ebitmap *e)
{
	struct ebitmap_node *n, *temp;

	if (!e)
		return;

	n = e->node;
	while (n) {
		temp = n;
		n = n->next;
		kfree(temp);
	}

	e->highbit = 0;
	e->node = NULL;
	return;
}

int ebitmap_read(struct ebitmap *e, void *fp)
{
	struct ebitmap_node *n = NULL;
	u32 mapunit, count, startbit, index;
	u64 map;
	__le32 buf[3];
	int rc, i;

	ebitmap_init(e);

	rc = next_entry(buf, fp, sizeof buf);
	if (rc < 0)
		goto out;

	mapunit = le32_to_cpu(buf[0]);
	e->highbit = le32_to_cpu(buf[1]);
	count = le32_to_cpu(buf[2]);

	if (mapunit != BITS_PER_U64) {
		printk(KERN_ERR "SELinux: ebitmap: map size %u does not "
		       "match my size %Zd (high bit was %d)\n",
		       mapunit, BITS_PER_U64, e->highbit);
		goto bad;
	}

	/* round up e->highbit */
	e->highbit += EBITMAP_SIZE - 1;
	e->highbit -= (e->highbit % EBITMAP_SIZE);

	if (!e->highbit) {
		e->node = NULL;
		goto ok;
	}

	for (i = 0; i < count; i++) {
		rc = next_entry(&startbit, fp, sizeof(u32));
		if (rc < 0) {
			printk(KERN_ERR "SELinux: ebitmap: truncated map\n");
			goto bad;
		}
		startbit = le32_to_cpu(startbit);

		if (startbit & (mapunit - 1)) {
			printk(KERN_ERR "SELinux: ebitmap start bit (%d) is "
			       "not a multiple of the map unit size (%u)\n",
			       startbit, mapunit);
			goto bad;
		}
		if (startbit > e->highbit - mapunit) {
			printk(KERN_ERR "SELinux: ebitmap start bit (%d) is "
			       "beyond the end of the bitmap (%u)\n",
			       startbit, (e->highbit - mapunit));
			goto bad;
		}

		if (!n || startbit >= n->startbit + EBITMAP_SIZE) {
			struct ebitmap_node *tmp;
			tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
			if (!tmp) {
				printk(KERN_ERR
				       "SELinux: ebitmap: out of memory\n");
				rc = -ENOMEM;
				goto bad;
			}
			/* round down */
			tmp->startbit = startbit - (startbit % EBITMAP_SIZE);
			if (n)
				n->next = tmp;
			else
				e->node = tmp;
			n = tmp;
		} else if (startbit <= n->startbit) {
			printk(KERN_ERR "SELinux: ebitmap: start bit %d"
			       " comes after start bit %d\n",
			       startbit, n->startbit);
			goto bad;
		}

		rc = next_entry(&map, fp, sizeof(u64));
		if (rc < 0) {
			printk(KERN_ERR "SELinux: ebitmap: truncated map\n");
			goto bad;
		}
		map = le64_to_cpu(map);

		index = (startbit - n->startbit) / EBITMAP_UNIT_SIZE;
		while (map) {
			n->maps[index++] = map & (-1UL);
			map = EBITMAP_SHIFT_UNIT_SIZE(map);
		}
	}
ok:
	rc = 0;
out:
	return rc;
bad:
	if (!rc)
		rc = -EINVAL;
	ebitmap_destroy(e);
	goto out;
}

int ebitmap_write(struct ebitmap *e, void *fp)
{
	struct ebitmap_node *n;
	u32 count;
	__le32 buf[3];
	u64 map;
	int bit, last_bit, last_startbit, rc;

	buf[0] = cpu_to_le32(BITS_PER_U64);

	count = 0;
	last_bit = 0;
	last_startbit = -1;
	ebitmap_for_each_positive_bit(e, n, bit) {
		if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
			count++;
			last_startbit = rounddown(bit, BITS_PER_U64);
		}
		last_bit = roundup(bit + 1, BITS_PER_U64);
	}
	buf[1] = cpu_to_le32(last_bit);
	buf[2] = cpu_to_le32(count);

	rc = put_entry(buf, sizeof(u32), 3, fp);
	if (rc)
		return rc;

	map = 0;
	last_startbit = INT_MIN;
	ebitmap_for_each_positive_bit(e, n, bit) {
		if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
			__le64 buf64[1];

			/* this is the very first bit */
			if (!map) {
				last_startbit = rounddown(bit, BITS_PER_U64);
				map = (u64)1 << (bit - last_startbit);
				continue;
			}

			/* write the last node */
			buf[0] = cpu_to_le32(last_startbit);
			rc = put_entry(buf, sizeof(u32), 1, fp);
			if (rc)
				return rc;

			buf64[0] = cpu_to_le64(map);
			rc = put_entry(buf64, sizeof(u64), 1, fp);
			if (rc)
				return rc;

			/* set up for the next node */
			map = 0;
			last_startbit = rounddown(bit, BITS_PER_U64);
		}
		map |= (u64)1 << (bit - last_startbit);
	}
	/* write the last node */
	if (map) {
		__le64 buf64[1];

		/* write the last node */
		buf[0] = cpu_to_le32(last_startbit);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;

		buf64[0] = cpu_to_le64(map);
		rc = put_entry(buf64, sizeof(u64), 1, fp);
		if (rc)
			return rc;
	}
	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Implementation of the extensible bitmap type.
	3	*
	4	* Author : Stephen Smalley, <sds@epoch.ncsc.mil>
	5	*/
7420ed23 VY	6	/*
	7	* Updated: Hewlett-Packard <paul.moore@hp.com>
	8	*
02752760	9	* Added support to import/export the NetLabel category bitmap
7420ed23 VY	10	*
	11	* (c) Copyright Hewlett-Packard Development Company, L.P., 2006
	12	*/
9fe79ad1 KK	13	/*
	14	* Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
	15	* Applied standard bit operations to improve bitmap scanning.
	16	*/
7420ed23	17
1da177e4 LT	18	#include <linux/kernel.h>
	19	#include <linux/slab.h>
	20	#include <linux/errno.h>
02752760	21	#include <net/netlabel.h>
1da177e4 LT	22	#include "ebitmap.h"
	23	#include "policydb.h"
	24
cee74f47 EP	25	#define BITS_PER_U64 (sizeof(u64) * 8)
cee74f47 EP	26
1da177e4 LT	27	int ebitmap_cmp(struct ebitmap e1, struct ebitmap e2)
	28	{
	29	struct ebitmap_node n1, n2;
	30
	31	if (e1->highbit != e2->highbit)
	32	return 0;
	33
	34	n1 = e1->node;
	35	n2 = e2->node;
	36	while (n1 && n2 &&
	37	(n1->startbit == n2->startbit) &&
9fe79ad1	38	!memcmp(n1->maps, n2->maps, EBITMAP_SIZE / 8)) {
1da177e4 LT	39	n1 = n1->next;
	40	n2 = n2->next;
	41	}
	42
	43	if (n1 \|\| n2)
	44	return 0;
	45
	46	return 1;
	47	}
	48
	49	int ebitmap_cpy(struct ebitmap dst, struct ebitmap src)
	50	{
	51	struct ebitmap_node n, new, *prev;
	52
	53	ebitmap_init(dst);
	54	n = src->node;
	55	prev = NULL;
	56	while (n) {
89d155ef	57	new = kzalloc(sizeof(*new), GFP_ATOMIC);
1da177e4 LT	58	if (!new) {
	59	ebitmap_destroy(dst);
	60	return -ENOMEM;
	61	}
1da177e4	62	new->startbit = n->startbit;
9fe79ad1	63	memcpy(new->maps, n->maps, EBITMAP_SIZE / 8);
1da177e4 LT	64	new->next = NULL;
	65	if (prev)
	66	prev->next = new;
	67	else
	68	dst->node = new;
	69	prev = new;
	70	n = n->next;
	71	}
	72
	73	dst->highbit = src->highbit;
	74	return 0;
	75	}
	76
02752760	77	#ifdef CONFIG_NETLABEL
7420ed23	78	/**
02752760 PM	79	* ebitmap_netlbl_export - Export an ebitmap into a NetLabel category bitmap
	80	* @ebmap: the ebitmap to export
	81	* @catmap: the NetLabel category bitmap
7420ed23 VY	82	*
7420ed23 VY	83	* Description:
02752760 PM	84	* Export a SELinux extensibile bitmap into a NetLabel category bitmap.
02752760 PM	85	* Returns zero on success, negative values on error.
7420ed23 VY	86	*
7420ed23 VY	87	*/
02752760 PM	88	int ebitmap_netlbl_export(struct ebitmap *ebmap,
02752760 PM	89	struct netlbl_lsm_secattr_catmap **catmap)
7420ed23	90	{
02752760 PM	91	struct ebitmap_node *e_iter = ebmap->node;
02752760 PM	92	struct netlbl_lsm_secattr_catmap *c_iter;
9fe79ad1 KK	93	u32 cmap_idx, cmap_sft;
9fe79ad1 KK	94	int i;
02752760	95
9fe79ad1 KK	96	/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
	97	* however, it is not always compatible with an array of unsigned long
	98	* in ebitmap_node.
	99	* In addition, you should pay attention the following implementation
	100	* assumes unsigned long has a width equal with or less than 64-bit.
	101	*/
02752760 PM	102
	103	if (e_iter == NULL) {
	104	*catmap = NULL;
bf0edf39 PM	105	return 0;
	106	}
	107
02752760 PM	108	c_iter = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
02752760 PM	109	if (c_iter == NULL)
7420ed23	110	return -ENOMEM;
02752760 PM	111	*catmap = c_iter;
	112	c_iter->startbit = e_iter->startbit & ~(NETLBL_CATMAP_SIZE - 1);
	113
dbc74c65	114	while (e_iter) {
9fe79ad1 KK	115	for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
	116	unsigned int delta, e_startbit, c_endbit;
	117
	118	e_startbit = e_iter->startbit + i * EBITMAP_UNIT_SIZE;
	119	c_endbit = c_iter->startbit + NETLBL_CATMAP_SIZE;
	120	if (e_startbit >= c_endbit) {
	121	c_iter->next
	122	= netlbl_secattr_catmap_alloc(GFP_ATOMIC);
	123	if (c_iter->next == NULL)
	124	goto netlbl_export_failure;
	125	c_iter = c_iter->next;
	126	c_iter->startbit
	127	= e_startbit & ~(NETLBL_CATMAP_SIZE - 1);
	128	}
	129	delta = e_startbit - c_iter->startbit;
	130	cmap_idx = delta / NETLBL_CATMAP_MAPSIZE;
	131	cmap_sft = delta % NETLBL_CATMAP_MAPSIZE;
	132	c_iter->bitmap[cmap_idx]
c36f74e6	133	\|= e_iter->maps[i] << cmap_sft;
02752760	134	}
6d2b6855	135	e_iter = e_iter->next;
02752760	136	}
7420ed23	137
7420ed23	138	return 0;
02752760 PM	139
	140	netlbl_export_failure:
	141	netlbl_secattr_catmap_free(*catmap);
	142	return -ENOMEM;
7420ed23 VY	143	}
	144
	145	/**
02752760	146	* ebitmap_netlbl_import - Import a NetLabel category bitmap into an ebitmap
9fe79ad1	147	* @ebmap: the ebitmap to import
02752760	148	* @catmap: the NetLabel category bitmap
7420ed23 VY	149	*
7420ed23 VY	150	* Description:
02752760 PM	151	* Import a NetLabel category bitmap into a SELinux extensibile bitmap.
02752760 PM	152	* Returns zero on success, negative values on error.
7420ed23 VY	153	*
7420ed23 VY	154	*/
02752760 PM	155	int ebitmap_netlbl_import(struct ebitmap *ebmap,
02752760 PM	156	struct netlbl_lsm_secattr_catmap *catmap)
7420ed23	157	{
02752760 PM	158	struct ebitmap_node *e_iter = NULL;
	159	struct ebitmap_node *emap_prev = NULL;
	160	struct netlbl_lsm_secattr_catmap *c_iter = catmap;
9fe79ad1	161	u32 c_idx, c_pos, e_idx, e_sft;
7420ed23	162
9fe79ad1 KK	163	/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
	164	* however, it is not always compatible with an array of unsigned long
	165	* in ebitmap_node.
	166	* In addition, you should pay attention the following implementation
	167	* assumes unsigned long has a width equal with or less than 64-bit.
	168	*/
7420ed23	169
02752760 PM	170	do {
02752760 PM	171	for (c_idx = 0; c_idx < NETLBL_CATMAP_MAPCNT; c_idx++) {
9fe79ad1 KK	172	unsigned int delta;
	173	u64 map = c_iter->bitmap[c_idx];
	174
	175	if (!map)
02752760	176	continue;
7420ed23	177
9fe79ad1 KK	178	c_pos = c_iter->startbit
	179	+ c_idx * NETLBL_CATMAP_MAPSIZE;
	180	if (!e_iter
	181	\|\| c_pos >= e_iter->startbit + EBITMAP_SIZE) {
	182	e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);
	183	if (!e_iter)
	184	goto netlbl_import_failure;
	185	e_iter->startbit
	186	= c_pos - (c_pos % EBITMAP_SIZE);
	187	if (emap_prev == NULL)
	188	ebmap->node = e_iter;
	189	else
	190	emap_prev->next = e_iter;
	191	emap_prev = e_iter;
	192	}
	193	delta = c_pos - e_iter->startbit;
	194	e_idx = delta / EBITMAP_UNIT_SIZE;
	195	e_sft = delta % EBITMAP_UNIT_SIZE;
	196	while (map) {
	197	e_iter->maps[e_idx++] \|= map & (-1UL);
087feb98	198	map = EBITMAP_SHIFT_UNIT_SIZE(map);
9fe79ad1	199	}
02752760 PM	200	}
02752760 PM	201	c_iter = c_iter->next;
dbc74c65	202	} while (c_iter);
02752760	203	if (e_iter != NULL)
9fe79ad1	204	ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
7420ed23	205	else
02752760	206	ebitmap_destroy(ebmap);
7420ed23 VY	207
7420ed23 VY	208	return 0;
02752760 PM	209
	210	netlbl_import_failure:
	211	ebitmap_destroy(ebmap);
	212	return -ENOMEM;
7420ed23	213	}
02752760	214	#endif /* CONFIG_NETLABEL */
7420ed23	215
1da177e4 LT	216	int ebitmap_contains(struct ebitmap e1, struct ebitmap e2)
	217	{
	218	struct ebitmap_node n1, n2;
9fe79ad1	219	int i;
1da177e4 LT	220
	221	if (e1->highbit < e2->highbit)
	222	return 0;
	223
	224	n1 = e1->node;
	225	n2 = e2->node;
	226	while (n1 && n2 && (n1->startbit <= n2->startbit)) {
	227	if (n1->startbit < n2->startbit) {
	228	n1 = n1->next;
	229	continue;
	230	}
9fe79ad1 KK	231	for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
	232	if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
	233	return 0;
	234	}
1da177e4 LT	235
	236	n1 = n1->next;
	237	n2 = n2->next;
	238	}
	239
	240	if (n2)
	241	return 0;
	242
	243	return 1;
	244	}
	245
	246	int ebitmap_get_bit(struct ebitmap *e, unsigned long bit)
	247	{
	248	struct ebitmap_node *n;
	249
	250	if (e->highbit < bit)
	251	return 0;
	252
	253	n = e->node;
	254	while (n && (n->startbit <= bit)) {
9fe79ad1 KK	255	if ((n->startbit + EBITMAP_SIZE) > bit)
9fe79ad1 KK	256	return ebitmap_node_get_bit(n, bit);
1da177e4 LT	257	n = n->next;
	258	}
	259
	260	return 0;
	261	}
	262
	263	int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value)
	264	{
	265	struct ebitmap_node n, prev, *new;
	266
	267	prev = NULL;
	268	n = e->node;
	269	while (n && n->startbit <= bit) {
9fe79ad1	270	if ((n->startbit + EBITMAP_SIZE) > bit) {
1da177e4	271	if (value) {
9fe79ad1	272	ebitmap_node_set_bit(n, bit);
1da177e4	273	} else {
9fe79ad1 KK	274	unsigned int s;
	275
	276	ebitmap_node_clr_bit(n, bit);
	277
	278	s = find_first_bit(n->maps, EBITMAP_SIZE);
	279	if (s < EBITMAP_SIZE)
	280	return 0;
	281
	282	/* drop this node from the bitmap */
	283	if (!n->next) {
	284	/*
	285	* this was the highest map
	286	* within the bitmap
	287	*/
1da177e4	288	if (prev)
9fe79ad1 KK	289	e->highbit = prev->startbit
9fe79ad1 KK	290	+ EBITMAP_SIZE;
1da177e4	291	else
9fe79ad1	292	e->highbit = 0;
1da177e4	293	}
9fe79ad1 KK	294	if (prev)
	295	prev->next = n->next;
	296	else
	297	e->node = n->next;
	298	kfree(n);
1da177e4 LT	299	}
	300	return 0;
	301	}
	302	prev = n;
	303	n = n->next;
	304	}
	305
	306	if (!value)
	307	return 0;
	308
89d155ef	309	new = kzalloc(sizeof(*new), GFP_ATOMIC);
1da177e4 LT	310	if (!new)
1da177e4 LT	311	return -ENOMEM;
1da177e4	312
9fe79ad1 KK	313	new->startbit = bit - (bit % EBITMAP_SIZE);
9fe79ad1 KK	314	ebitmap_node_set_bit(new, bit);
1da177e4 LT	315
	316	if (!n)
	317	/* this node will be the highest map within the bitmap */
9fe79ad1	318	e->highbit = new->startbit + EBITMAP_SIZE;
1da177e4 LT	319
	320	if (prev) {
	321	new->next = prev->next;
	322	prev->next = new;
	323	} else {
	324	new->next = e->node;
	325	e->node = new;
	326	}
	327
	328	return 0;
	329	}
	330
	331	void ebitmap_destroy(struct ebitmap *e)
	332	{
	333	struct ebitmap_node n, temp;
	334
	335	if (!e)
	336	return;
	337
	338	n = e->node;
	339	while (n) {
	340	temp = n;
	341	n = n->next;
	342	kfree(temp);
	343	}
	344
	345	e->highbit = 0;
	346	e->node = NULL;
	347	return;
	348	}
	349
	350	int ebitmap_read(struct ebitmap e, void fp)
	351	{
9fe79ad1 KK	352	struct ebitmap_node *n = NULL;
	353	u32 mapunit, count, startbit, index;
	354	u64 map;
b5bf6c55	355	__le32 buf[3];
9fe79ad1	356	int rc, i;
1da177e4 LT	357
	358	ebitmap_init(e);
	359
	360	rc = next_entry(buf, fp, sizeof buf);
	361	if (rc < 0)
	362	goto out;
	363
9fe79ad1	364	mapunit = le32_to_cpu(buf[0]);
1da177e4 LT	365	e->highbit = le32_to_cpu(buf[1]);
	366	count = le32_to_cpu(buf[2]);
	367
cee74f47	368	if (mapunit != BITS_PER_U64) {
454d972c	369	printk(KERN_ERR "SELinux: ebitmap: map size %u does not "
9fe79ad1	370	"match my size %Zd (high bit was %d)\n",
cee74f47	371	mapunit, BITS_PER_U64, e->highbit);
1da177e4 LT	372	goto bad;
1da177e4 LT	373	}
9fe79ad1 KK	374
	375	/* round up e->highbit */
	376	e->highbit += EBITMAP_SIZE - 1;
	377	e->highbit -= (e->highbit % EBITMAP_SIZE);
	378
1da177e4 LT	379	if (!e->highbit) {
	380	e->node = NULL;
	381	goto ok;
	382	}
9fe79ad1	383
1da177e4	384	for (i = 0; i < count; i++) {
9fe79ad1	385	rc = next_entry(&startbit, fp, sizeof(u32));
1da177e4	386	if (rc < 0) {
454d972c	387	printk(KERN_ERR "SELinux: ebitmap: truncated map\n");
1da177e4 LT	388	goto bad;
1da177e4 LT	389	}
9fe79ad1	390	startbit = le32_to_cpu(startbit);
1da177e4	391
9fe79ad1	392	if (startbit & (mapunit - 1)) {
454d972c	393	printk(KERN_ERR "SELinux: ebitmap start bit (%d) is "
087feb98	394	"not a multiple of the map unit size (%u)\n",
9fe79ad1 KK	395	startbit, mapunit);
9fe79ad1 KK	396	goto bad;
1da177e4	397	}
9fe79ad1	398	if (startbit > e->highbit - mapunit) {
454d972c	399	printk(KERN_ERR "SELinux: ebitmap start bit (%d) is "
087feb98	400	"beyond the end of the bitmap (%u)\n",
9fe79ad1 KK	401	startbit, (e->highbit - mapunit));
	402	goto bad;
	403	}
	404
	405	if (!n \|\| startbit >= n->startbit + EBITMAP_SIZE) {
	406	struct ebitmap_node *tmp;
	407	tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
	408	if (!tmp) {
	409	printk(KERN_ERR
454d972c	410	"SELinux: ebitmap: out of memory\n");
9fe79ad1 KK	411	rc = -ENOMEM;
	412	goto bad;
	413	}
	414	/* round down */
	415	tmp->startbit = startbit - (startbit % EBITMAP_SIZE);
7696ee80	416	if (n)
9fe79ad1	417	n->next = tmp;
7696ee80	418	else
9fe79ad1	419	e->node = tmp;
9fe79ad1 KK	420	n = tmp;
9fe79ad1 KK	421	} else if (startbit <= n->startbit) {
454d972c	422	printk(KERN_ERR "SELinux: ebitmap: start bit %d"
9fe79ad1 KK	423	" comes after start bit %d\n",
	424	startbit, n->startbit);
	425	goto bad;
1da177e4	426	}
9fe79ad1	427
1da177e4 LT	428	rc = next_entry(&map, fp, sizeof(u64));
1da177e4 LT	429	if (rc < 0) {
454d972c	430	printk(KERN_ERR "SELinux: ebitmap: truncated map\n");
9fe79ad1	431	goto bad;
1da177e4	432	}
9fe79ad1	433	map = le64_to_cpu(map);
1da177e4	434
9fe79ad1 KK	435	index = (startbit - n->startbit) / EBITMAP_UNIT_SIZE;
9fe79ad1 KK	436	while (map) {
087feb98 KK	437	n->maps[index++] = map & (-1UL);
087feb98 KK	438	map = EBITMAP_SHIFT_UNIT_SIZE(map);
1da177e4	439	}
1da177e4	440	}
1da177e4 LT	441	ok:
	442	rc = 0;
	443	out:
	444	return rc;
1da177e4 LT	445	bad:
	446	if (!rc)
	447	rc = -EINVAL;
	448	ebitmap_destroy(e);
	449	goto out;
	450	}
cee74f47 EP	451
	452	int ebitmap_write(struct ebitmap e, void fp)
	453	{
	454	struct ebitmap_node *n;
	455	u32 count;
	456	__le32 buf[3];
	457	u64 map;
	458	int bit, last_bit, last_startbit, rc;
	459
	460	buf[0] = cpu_to_le32(BITS_PER_U64);
	461
	462	count = 0;
	463	last_bit = 0;
	464	last_startbit = -1;
	465	ebitmap_for_each_positive_bit(e, n, bit) {
	466	if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
	467	count++;
	468	last_startbit = rounddown(bit, BITS_PER_U64);
	469	}
	470	last_bit = roundup(bit + 1, BITS_PER_U64);
	471	}
	472	buf[1] = cpu_to_le32(last_bit);
	473	buf[2] = cpu_to_le32(count);
	474
	475	rc = put_entry(buf, sizeof(u32), 3, fp);
	476	if (rc)
	477	return rc;
	478
	479	map = 0;
	480	last_startbit = INT_MIN;
	481	ebitmap_for_each_positive_bit(e, n, bit) {
	482	if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) {
	483	__le64 buf64[1];
	484
	485	/* this is the very first bit */
	486	if (!map) {
	487	last_startbit = rounddown(bit, BITS_PER_U64);
	488	map = (u64)1 << (bit - last_startbit);
	489	continue;
	490	}
	491
	492	/* write the last node */
	493	buf[0] = cpu_to_le32(last_startbit);
	494	rc = put_entry(buf, sizeof(u32), 1, fp);
	495	if (rc)
	496	return rc;
	497
	498	buf64[0] = cpu_to_le64(map);
	499	rc = put_entry(buf64, sizeof(u64), 1, fp);
	500	if (rc)
	501	return rc;
	502
	503	/* set up for the next node */
	504	map = 0;
	505	last_startbit = rounddown(bit, BITS_PER_U64);
	506	}
	507	map \|= (u64)1 << (bit - last_startbit);
	508	}
	509	/* write the last node */
	510	if (map) {
	511	__le64 buf64[1];
	512
	513	/* write the last node */
	514	buf[0] = cpu_to_le32(last_startbit);
515	rc = put_entry(buf, sizeof(u32), 1, fp);
516	if (rc)
517	return rc;
518
519	buf64[0] = cpu_to_le64(map);
520	rc = put_entry(buf64, sizeof(u64), 1, fp);
521	if (rc)
522	return rc;
523	}
524	return 0;
525	}