1 files changed, 114 insertions, 0 deletions
diff --git a/include/net/inetpeer.h b/include/net/inetpeer.h
new file mode 100644
index 00000000..8a159cc3
--- /dev/null
+++ b/include/net/inetpeer.h
@@ -0,0 +1,114 @@
+/*
+ *		INETPEER - A storage for permanent information about peers
+ *
+ *  Authors:	Andrey V. Savochkin <saw@msu.ru>
+ */
+
+#ifndef _NET_INETPEER_H
+#define _NET_INETPEER_H
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/spinlock.h>
+#include <linux/rtnetlink.h>
+#include <net/ipv6.h>
+#include <asm/atomic.h>
+
+struct inetpeer_addr_base {
+	union {
+		__be32			a4;
+		__be32			a6[4];
+	};
+};
+
+struct inetpeer_addr {
+	struct inetpeer_addr_base	addr;
+	__u16				family;
+};
+
+struct inet_peer {
+	/* group together avl_left,avl_right,v4daddr to speedup lookups */
+	struct inet_peer __rcu	*avl_left, *avl_right;
+	struct inetpeer_addr	daddr;
+	__u32			avl_height;
+	struct list_head	unused;
+	__u32			dtime;		/* the time of last use of not
+						 * referenced entries */
+	atomic_t		refcnt;
+	/*
+	 * Once inet_peer is queued for deletion (refcnt == -1), following fields
+	 * are not available: rid, ip_id_count, tcp_ts, tcp_ts_stamp, metrics
+	 * We can share memory with rcu_head to help keep inet_peer small.
+	 */
+	union {
+		struct {
+			atomic_t			rid;		/* Frag reception counter */
+			atomic_t			ip_id_count;	/* IP ID for the next packet */
+			__u32				tcp_ts;
+			__u32				tcp_ts_stamp;
+			u32				metrics[RTAX_MAX];
+			u32				rate_tokens;	/* rate limiting for ICMP */
+			unsigned long			rate_last;
+			unsigned long			pmtu_expires;
+			u32				pmtu_orig;
+			u32				pmtu_learned;
+			struct inetpeer_addr_base	redirect_learned;
+		};
+		struct rcu_head         rcu;
+	};
+};
+
+void			inet_initpeers(void) __init;
+
+#define INETPEER_METRICS_NEW	(~(u32) 0)
+
+static inline bool inet_metrics_new(const struct inet_peer *p)
+{
+	return p->metrics[RTAX_LOCK-1] == INETPEER_METRICS_NEW;
+}
+
+/* can be called with or without local BH being disabled */
+struct inet_peer	*inet_getpeer(struct inetpeer_addr *daddr, int create);
+
+static inline struct inet_peer *inet_getpeer_v4(__be32 v4daddr, int create)
+{
+	struct inetpeer_addr daddr;
+
+	daddr.addr.a4 = v4daddr;
+	daddr.family = AF_INET;
+	return inet_getpeer(&daddr, create);
+}
+
+static inline struct inet_peer *inet_getpeer_v6(const struct in6_addr *v6daddr, int create)
+{
+	struct inetpeer_addr daddr;
+
+	ipv6_addr_copy((struct in6_addr *)daddr.addr.a6, v6daddr);
+	daddr.family = AF_INET6;
+	return inet_getpeer(&daddr, create);
+}
+
+/* can be called from BH context or outside */
+extern void inet_putpeer(struct inet_peer *p);
+extern bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
+
+/*
+ * temporary check to make sure we dont access rid, ip_id_count, tcp_ts,
+ * tcp_ts_stamp if no refcount is taken on inet_peer
+ */
+static inline void inet_peer_refcheck(const struct inet_peer *p)
+{
+	WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
+}
+
+
+/* can be called with or without local BH being disabled */
+static inline __u16	inet_getid(struct inet_peer *p, int more)
+{
+	more++;
+	inet_peer_refcheck(p);
+	return atomic_add_return(more, &p->ip_id_count) - more;
+}
+
+#endif /* _NET_INETPEER_H */