netlabel: Move bitmap manipulation functions to the NetLabel core.

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

Signed-off-by: Huw Davies <huw@codeweavers.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This commit is contained in:
Huw Davies 2016-06-27 15:02:51 -04:00 committed by Paul Moore
parent e67ae213c7
commit 3faa8f982f
3 changed files with 85 additions and 79 deletions

View File

@ -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)
*/

View File

@ -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);

View File

@ -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
*/