apparmor: split out shared policy_XXX fns to lib

Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/include/lib.h

@@ -91,4 +91,85 @@ static inline bool mediated_filesystem(struct dentry *dentry)
 	return !(dentry->d_sb->s_flags & MS_NOUSER);
 }
 
+/* struct aa_policy - common part of both namespaces and profiles
+ * @name: name of the object
+ * @hname - The hierarchical name
+ * @list: list policy object is on
+ * @profiles: head of the profiles list contained in the object
+ */
+struct aa_policy {
+	char *name;
+	char *hname;
+	struct list_head list;
+	struct list_head profiles;
+};
+
+/**
+ * hname_tail - find the last component of an hname
+ * @name: hname to find the base profile name component of  (NOT NULL)
+ *
+ * Returns: the tail (base profile name) name component of an hname
+ */
+static inline const char *hname_tail(const char *hname)
+{
+	char *split;
+
+	hname = strim((char *)hname);
+	for (split = strstr(hname, "//"); split; split = strstr(hname, "//"))
+		hname = split + 2;
+
+	return hname;
+}
+
+/**
+ * __policy_find - find a policy by @name on a policy list
+ * @head: list to search  (NOT NULL)
+ * @name: name to search for  (NOT NULL)
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted policy that match @name or NULL if not found
+ */
+static inline struct aa_policy *__policy_find(struct list_head *head,
+					      const char *name)
+{
+	struct aa_policy *policy;
+
+	list_for_each_entry_rcu(policy, head, list) {
+		if (!strcmp(policy->name, name))
+			return policy;
+	}
+	return NULL;
+}
+
+/**
+ * __policy_strn_find - find a policy that's name matches @len chars of @str
+ * @head: list to search  (NOT NULL)
+ * @str: string to search for  (NOT NULL)
+ * @len: length of match required
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted policy that match @str or NULL if not found
+ *
+ * if @len == strlen(@strlen) then this is equiv to __policy_find
+ * other wise it allows searching for policy by a partial match of name
+ */
+static inline struct aa_policy *__policy_strn_find(struct list_head *head,
+					    const char *str, int len)
+{
+	struct aa_policy *policy;
+
+	list_for_each_entry_rcu(policy, head, list) {
+		if (aa_strneq(policy->name, str, len))
+			return policy;
+	}
+
+	return NULL;
+}
+
+bool aa_policy_init(struct aa_policy *policy, const char *prefix,
+		    const char *name);
+void aa_policy_destroy(struct aa_policy *policy);
+
 #endif /* AA_LIB_H */