Commit 3faa8f98 authored by Huw Davies's avatar Huw Davies Committed by Paul Moore
Browse files

netlabel: Move bitmap manipulation functions to the NetLabel core. 



This is to allow the CALIPSO labelling engine to use these.

Signed-off-by: default avatarHuw Davies <huw@codeweavers.com>
Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
parent e67ae213

include/net/netlabel.h

+6 −0
Original line number Diff line number Diff line
@@ -434,6 +434,12 @@ int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap, 
			  unsigned long bitmap,

			  gfp_t flags);



/* Bitmap functions

 */

int netlbl_bitmap_walk(const unsigned char *bitmap, u32 bitmap_len,

		       u32 offset, u8 state);

void netlbl_bitmap_setbit(unsigned char *bitmap, u32 bit, u8 state);



/*

 * LSM protocol operations (NetLabel LSM/kernel API)

 */

net/ipv4/cipso_ipv4.c

+9 −79
Original line number Diff line number Diff line
@@ -134,76 +134,6 @@ int cipso_v4_rbm_strictvalid = 1; 
 * Helper Functions

 */



/**

 * cipso_v4_bitmap_walk - Walk a bitmap looking for a bit

 * @bitmap: the bitmap

 * @bitmap_len: length in bits

 * @offset: starting offset

 * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit

 *

 * Description:

 * Starting at @offset, walk the bitmap from left to right until either the

 * desired bit is found or we reach the end.  Return the bit offset, -1 if

 * not found, or -2 if error.

 */

static int cipso_v4_bitmap_walk(const unsigned char *bitmap,

				u32 bitmap_len,

				u32 offset,

				u8 state)

{

	u32 bit_spot;

	u32 byte_offset;

	unsigned char bitmask;

	unsigned char byte;



	/* gcc always rounds to zero when doing integer division */

	byte_offset = offset / 8;

	byte = bitmap[byte_offset];

	bit_spot = offset;

	bitmask = 0x80 >> (offset % 8);



	while (bit_spot < bitmap_len) {

		if ((state && (byte & bitmask) == bitmask) ||

		    (state == 0 && (byte & bitmask) == 0))

			return bit_spot;



		bit_spot++;

		bitmask >>= 1;

		if (bitmask == 0) {

			byte = bitmap[++byte_offset];

			bitmask = 0x80;

		}

	}



	return -1;

}



/**

 * cipso_v4_bitmap_setbit - Sets a single bit in a bitmap

 * @bitmap: the bitmap

 * @bit: the bit

 * @state: if non-zero, set the bit (1) else clear the bit (0)

 *

 * Description:

 * Set a single bit in the bitmask.  Returns zero on success, negative values

 * on error.

 */

static void cipso_v4_bitmap_setbit(unsigned char *bitmap,

				   u32 bit,

				   u8 state)

{

	u32 byte_spot;

	u8 bitmask;



	/* gcc always rounds to zero when doing integer division */

	byte_spot = bit / 8;

	bitmask = 0x80 >> (bit % 8);

	if (state)

		bitmap[byte_spot] |= bitmask;

	else

		bitmap[byte_spot] &= ~bitmask;

}



/**

 * cipso_v4_cache_entry_free - Frees a cache entry

 * @entry: the entry to free
@@ -840,7 +770,7 @@ static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, 
		cipso_cat_size = doi_def->map.std->cat.cipso_size;

		cipso_array = doi_def->map.std->cat.cipso;

		for (;;) {

			cat = cipso_v4_bitmap_walk(bitmap,

			cat = netlbl_bitmap_walk(bitmap,

						 bitmap_len_bits,

						 cat + 1,

						 1);
@@ -909,7 +839,7 @@ static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, 
		}

		if (net_spot >= net_clen_bits)

			return -ENOSPC;

		cipso_v4_bitmap_setbit(net_cat, net_spot, 1);

		netlbl_bitmap_setbit(net_cat, net_spot, 1);



		if (net_spot > net_spot_max)

			net_spot_max = net_spot;
@@ -951,7 +881,7 @@ static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, 
	}



	for (;;) {

		net_spot = cipso_v4_bitmap_walk(net_cat,

		net_spot = netlbl_bitmap_walk(net_cat,

					      net_clen_bits,

					      net_spot + 1,

					      1);

net/netlabel/netlabel_kapi.c

+70 −0
Original line number Diff line number Diff line
@@ -728,6 +728,76 @@ int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap, 
	return 0;

}



/* Bitmap functions

 */



/**

 * netlbl_bitmap_walk - Walk a bitmap looking for a bit

 * @bitmap: the bitmap

 * @bitmap_len: length in bits

 * @offset: starting offset

 * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit

 *

 * Description:

 * Starting at @offset, walk the bitmap from left to right until either the

 * desired bit is found or we reach the end.  Return the bit offset, -1 if

 * not found, or -2 if error.

 */

int netlbl_bitmap_walk(const unsigned char *bitmap, u32 bitmap_len,

		       u32 offset, u8 state)

{

	u32 bit_spot;

	u32 byte_offset;

	unsigned char bitmask;

	unsigned char byte;



	byte_offset = offset / 8;

	byte = bitmap[byte_offset];

	bit_spot = offset;

	bitmask = 0x80 >> (offset % 8);



	while (bit_spot < bitmap_len) {

		if ((state && (byte & bitmask) == bitmask) ||

		    (state == 0 && (byte & bitmask) == 0))

			return bit_spot;



		bit_spot++;

		bitmask >>= 1;

		if (bitmask == 0) {

			byte = bitmap[++byte_offset];

			bitmask = 0x80;

		}

	}



	return -1;

}

EXPORT_SYMBOL(netlbl_bitmap_walk);



/**

 * netlbl_bitmap_setbit - Sets a single bit in a bitmap

 * @bitmap: the bitmap

 * @bit: the bit

 * @state: if non-zero, set the bit (1) else clear the bit (0)

 *

 * Description:

 * Set a single bit in the bitmask.  Returns zero on success, negative values

 * on error.

 */

void netlbl_bitmap_setbit(unsigned char *bitmap, u32 bit, u8 state)

{

	u32 byte_spot;

	u8 bitmask;



	/* gcc always rounds to zero when doing integer division */

	byte_spot = bit / 8;

	bitmask = 0x80 >> (bit % 8);

	if (state)

		bitmap[byte_spot] |= bitmask;

	else

		bitmap[byte_spot] &= ~bitmask;

}

EXPORT_SYMBOL(netlbl_bitmap_setbit);



/*

 * LSM Functions

 */