inet_diag: Generalize inet_diag dump and get_exact calls

Introduce two callbacks in inet_diag_handler -- one for dumping all
sockets (with filters) and the other one for dumping a single sk.

Replace direct calls to icsk handlers with indirect calls to callbacks
provided by handlers.

Make existing TCP and DCCP handlers use provided helpers for icsk-s.

The UDP diag module will provide its own.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/inet_diag.h b/include/linux/inet_diag.h
index eaf5865..78972a1 100644
--- a/include/linux/inet_diag.h
+++ b/include/linux/inet_diag.h
@@ -138,9 +138,18 @@
 struct nlattr;
 struct nlmsghdr;
 struct sk_buff;
+struct netlink_callback;
 
 struct inet_diag_handler {
-	struct inet_hashinfo    *idiag_hashinfo;
+	void			(*dump)(struct sk_buff *skb,
+					struct netlink_callback *cb,
+					struct inet_diag_req *r,
+					struct nlattr *bc);
+
+	int			(*dump_one)(struct sk_buff *in_skb,
+					const struct nlmsghdr *nlh,
+					struct inet_diag_req *req);
+
 	void			(*idiag_get_info)(struct sock *sk,
 						  struct inet_diag_msg *r,
 						  void *info);
@@ -152,6 +161,13 @@
 			      struct sk_buff *skb, struct inet_diag_req *req,
 			      u32 pid, u32 seq, u16 nlmsg_flags,
 			      const struct nlmsghdr *unlh);
+void inet_diag_dump_icsk(struct inet_hashinfo *h, struct sk_buff *skb,
+		struct netlink_callback *cb, struct inet_diag_req *r,
+		struct nlattr *bc);
+int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
+		struct sk_buff *in_skb, const struct nlmsghdr *nlh,
+		struct inet_diag_req *req);
+
 int inet_diag_bc_sk(const struct nlattr *_bc, struct sock *sk);
 int inet_diag_check_cookie(struct sock *sk, struct inet_diag_req *req);