1 files changed, 57 insertions, 0 deletions
diff --git a/security/selinux/ss/sidtab.h b/security/selinux/ss/sidtab.h
new file mode 100644
index 000000000..a1a1d2617
--- /dev/null
+++ b/security/selinux/ss/sidtab.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * A security identifier table (sidtab) is a hash table
+ * of security context structures indexed by SID value.
+ *
+ * Author : Stephen Smalley, <sds@tycho.nsa.gov>
+ */
+#ifndef _SS_SIDTAB_H_
+#define _SS_SIDTAB_H_
+
+#include "context.h"
+
+struct sidtab_node {
+	u32 sid;		/* security identifier */
+	struct context context;	/* security context structure */
+	struct sidtab_node *next;
+};
+
+#define SIDTAB_HASH_BITS 7
+#define SIDTAB_HASH_BUCKETS (1 << SIDTAB_HASH_BITS)
+#define SIDTAB_HASH_MASK (SIDTAB_HASH_BUCKETS-1)
+
+#define SIDTAB_SIZE SIDTAB_HASH_BUCKETS
+
+struct sidtab {
+	struct sidtab_node **htable;
+	unsigned int nel;	/* number of elements */
+	unsigned int next_sid;	/* next SID to allocate */
+	unsigned char shutdown;
+#define SIDTAB_CACHE_LEN	3
+	struct sidtab_node *cache[SIDTAB_CACHE_LEN];
+	spinlock_t lock;
+};
+
+int sidtab_init(struct sidtab *s);
+int sidtab_insert(struct sidtab *s, u32 sid, struct context *context);
+struct context *sidtab_search(struct sidtab *s, u32 sid);
+struct context *sidtab_search_force(struct sidtab *s, u32 sid);
+
+int sidtab_map(struct sidtab *s,
+	       int (*apply) (u32 sid,
+			     struct context *context,
+			     void *args),
+	       void *args);
+
+int sidtab_context_to_sid(struct sidtab *s,
+			  struct context *context,
+			  u32 *sid);
+
+void sidtab_hash_eval(struct sidtab *h, char *tag);
+void sidtab_destroy(struct sidtab *s);
+void sidtab_set(struct sidtab *dst, struct sidtab *src);
+void sidtab_shutdown(struct sidtab *s);
+
+#endif	/* _SS_SIDTAB_H_ */
+
+