netlabel: Add a generic way to create ordered linked lists of network addrs

Create an ordered IP address linked list mechanism similar to the core
kernel's linked list construct.  The idea behind this list functionality
is to create an extensibile linked list ordered by IP address mask to
ease the matching of network addresses.  The linked list is ordered with
larger address masks at the front of the list and shorter address masks
at the end to facilitate overriding network entries with individual host
or subnet entries.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Reviewed-by: James Morris <jmorris@namei.org>

1 files changed, 174 insertions, 0 deletions

diff --git a/net/netlabel/netlabel_addrlist.h b/net/netlabel/netlabel_addrlist.h
new file mode 100644
index 000000000000..0c41df057fa8
--- /dev/null
+++ b/net/netlabel/netlabel_addrlist.h
@@ -0,0 +1,174 @@
+/*
+ * NetLabel Network Address Lists
+ *
+ * This file contains network address list functions used to manage ordered
+ * lists of network addresses for use by the NetLabel subsystem.  The NetLabel
+ * system manages static and dynamic label mappings for network protocols such
+ * as CIPSO and RIPSO.
+ *
+ * Author: Paul Moore <paul.moore@hp.com>
+ *
+ */
+
+/*
+ * (c) Copyright Hewlett-Packard Development Company, L.P., 2008
+ *
+ * This program is free software;  you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY;  without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program;  if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#ifndef _NETLABEL_ADDRLIST_H
+#define _NETLABEL_ADDRLIST_H
+
+#include <linux/types.h>
+#include <linux/rcupdate.h>
+#include <linux/list.h>
+#include <linux/in6.h>
+
+/**
+ * struct netlbl_af4list - NetLabel IPv4 address list
+ * @addr: IPv4 address
+ * @mask: IPv4 address mask
+ * @valid: valid flag
+ * @list: list structure, used internally
+ */
+struct netlbl_af4list {
+	__be32 addr;
+	__be32 mask;
+
+	u32 valid;
+	struct list_head list;
+};
+
+/**
+ * struct netlbl_af6list - NetLabel IPv6 address list
+ * @addr: IPv6 address
+ * @mask: IPv6 address mask
+ * @valid: valid flag
+ * @list: list structure, used internally
+ */
+struct netlbl_af6list {
+	struct in6_addr addr;
+	struct in6_addr mask;
+
+	u32 valid;
+	struct list_head list;
+};
+
+#define __af4list_entry(ptr) container_of(ptr, struct netlbl_af4list, list)
+
+static inline struct netlbl_af4list *__af4list_valid(struct list_head *s,
+						     struct list_head *h)
+{
+	struct list_head *i = s;
+	struct netlbl_af4list *n = __af4list_entry(s);
+	while (i != h && !n->valid) {
+		i = i->next;
+		n = __af4list_entry(i);
+	}
+	return n;
+}
+
+static inline struct netlbl_af4list *__af4list_valid_rcu(struct list_head *s,
+							 struct list_head *h)
+{
+	struct list_head *i = s;
+	struct netlbl_af4list *n = __af4list_entry(s);
+	while (i != h && !n->valid) {
+		i = rcu_dereference(i->next);
+		n = __af4list_entry(i);
+	}
+	return n;
+}
+
+#define netlbl_af4list_foreach(iter, head)				\
+	for (iter = __af4list_valid((head)->next, head);		\
+	     prefetch(iter->list.next), &iter->list != (head);		\
+	     iter = __af4list_valid(iter->list.next, head))
+
+#define netlbl_af4list_foreach_rcu(iter, head)				\
+	for (iter = __af4list_valid_rcu((head)->next, head);		\
+	     prefetch(iter->list.next),	&iter->list != (head);		\
+	     iter = __af4list_valid_rcu(iter->list.next, head))
+
+#define netlbl_af4list_foreach_safe(iter, tmp, head)			\
+	for (iter = __af4list_valid((head)->next, head),		\
+		     tmp = __af4list_valid(iter->list.next, head);	\
+	     &iter->list != (head);					\
+	     iter = tmp, tmp = __af4list_valid(iter->list.next, head))
+
+int netlbl_af4list_add(struct netlbl_af4list *entry,
+		       struct list_head *head);
+struct netlbl_af4list *netlbl_af4list_remove(__be32 addr, __be32 mask,
+					     struct list_head *head);
+void netlbl_af4list_remove_entry(struct netlbl_af4list *entry);
+struct netlbl_af4list *netlbl_af4list_search(__be32 addr,
+					     struct list_head *head);
+
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+
+#define __af6list_entry(ptr) container_of(ptr, struct netlbl_af6list, list)
+
+static inline struct netlbl_af6list *__af6list_valid(struct list_head *s,
+						     struct list_head *h)
+{
+	struct list_head *i = s;
+	struct netlbl_af6list *n = __af6list_entry(s);
+	while (i != h && !n->valid) {
+		i = i->next;
+		n = __af6list_entry(i);
+	}
+	return n;
+}
+
+static inline struct netlbl_af6list *__af6list_valid_rcu(struct list_head *s,
+							 struct list_head *h)
+{
+	struct list_head *i = s;
+	struct netlbl_af6list *n = __af6list_entry(s);
+	while (i != h && !n->valid) {
+		i = rcu_dereference(i->next);
+		n = __af6list_entry(i);
+	}
+	return n;
+}
+
+#define netlbl_af6list_foreach(iter, head)				\
+	for (iter = __af6list_valid((head)->next, head);		\
+	     prefetch(iter->list.next),	&iter->list != (head);		\
+	     iter = __af6list_valid(iter->list.next, head))
+
+#define netlbl_af6list_foreach_rcu(iter, head)				\
+	for (iter = __af6list_valid_rcu((head)->next, head);		\
+	     prefetch(iter->list.next),	&iter->list != (head);		\
+	     iter = __af6list_valid_rcu(iter->list.next, head))
+
+#define netlbl_af6list_foreach_safe(iter, tmp, head)			\
+	for (iter = __af6list_valid((head)->next, head),		\
+		     tmp = __af6list_valid(iter->list.next, head);	\
+	     &iter->list != (head);					\
+	     iter = tmp, tmp = __af6list_valid(iter->list.next, head))
+
+int netlbl_af6list_add(struct netlbl_af6list *entry,
+		       struct list_head *head);
+struct netlbl_af6list *netlbl_af6list_remove(const struct in6_addr *addr,
+					     const struct in6_addr *mask,
+					     struct list_head *head);
+void netlbl_af6list_remove_entry(struct netlbl_af6list *entry);
+struct netlbl_af6list *netlbl_af6list_search(const struct in6_addr *addr,
+					     struct list_head *head);
+#endif /* IPV6 */
+
+#endif