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-rw-r--r--security/selinux/ss/ebitmap.h154
1 files changed, 154 insertions, 0 deletions
diff --git a/security/selinux/ss/ebitmap.h b/security/selinux/ss/ebitmap.h
new file mode 100644
index 000000000..e5b57dc3f
--- /dev/null
+++ b/security/selinux/ss/ebitmap.h
@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * 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@tycho.nsa.gov>
+ */
+#ifndef _SS_EBITMAP_H_
+#define _SS_EBITMAP_H_
+
+#include <net/netlabel.h>
+
+#ifdef CONFIG_64BIT
+#define EBITMAP_NODE_SIZE 64
+#else
+#define EBITMAP_NODE_SIZE 32
+#endif
+
+#define EBITMAP_UNIT_NUMS ((EBITMAP_NODE_SIZE-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)
+
+static inline unsigned int ebitmap_start_positive(const 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(const 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(const 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(const struct ebitmap *e1, const struct ebitmap *e2);
+int ebitmap_cpy(struct ebitmap *dst, const struct ebitmap *src);
+int ebitmap_and(struct ebitmap *dst, const struct ebitmap *e1, const struct ebitmap *e2);
+int ebitmap_contains(const struct ebitmap *e1, const struct ebitmap *e2, u32 last_e2bit);
+int ebitmap_get_bit(const 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);
+int ebitmap_write(const struct ebitmap *e, void *fp);
+u32 ebitmap_hash(const struct ebitmap *e, u32 hash);
+
+#ifdef CONFIG_NETLABEL
+int ebitmap_netlbl_export(struct ebitmap *ebmap,
+ struct netlbl_lsm_catmap **catmap);
+int ebitmap_netlbl_import(struct ebitmap *ebmap,
+ struct netlbl_lsm_catmap *catmap);
+#else
+static inline int ebitmap_netlbl_export(struct ebitmap *ebmap,
+ struct netlbl_lsm_catmap **catmap)
+{
+ return -ENOMEM;
+}
+static inline int ebitmap_netlbl_import(struct ebitmap *ebmap,
+ struct netlbl_lsm_catmap *catmap)
+{
+ return -ENOMEM;
+}
+#endif
+
+#endif /* _SS_EBITMAP_H_ */