1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _AF_NETLINK_H
3 #define _AF_NETLINK_H
4 
5 #include <linux/rhashtable.h>
6 #include <linux/atomic.h>
7 #include <linux/workqueue.h>
8 #include <net/sock.h>
9 
10 /* flags */
11 #define NETLINK_F_KERNEL_SOCKET		0x1
12 #define NETLINK_F_RECV_PKTINFO		0x2
13 #define NETLINK_F_BROADCAST_SEND_ERROR	0x4
14 #define NETLINK_F_RECV_NO_ENOBUFS	0x8
15 #define NETLINK_F_LISTEN_ALL_NSID	0x10
16 #define NETLINK_F_CAP_ACK		0x20
17 #define NETLINK_F_EXT_ACK		0x40
18 #define NETLINK_F_STRICT_CHK		0x80
19 
20 #define NLGRPSZ(x)	(ALIGN(x, sizeof(unsigned long) * 8) / 8)
21 #define NLGRPLONGS(x)	(NLGRPSZ(x)/sizeof(unsigned long))
22 
23 struct netlink_sock {
24 	/* struct sock has to be the first member of netlink_sock */
25 	struct sock		sk;
26 	u32			portid;
27 	u32			dst_portid;
28 	u32			dst_group;
29 	u32			flags;
30 	u32			subscriptions;
31 	u32			ngroups;
32 	unsigned long		*groups;
33 	unsigned long		state;
34 	size_t			max_recvmsg_len;
35 	wait_queue_head_t	wait;
36 	bool			bound;
37 	bool			cb_running;
38 	int			dump_done_errno;
39 	struct netlink_callback	cb;
40 	struct mutex		*cb_mutex;
41 	struct mutex		cb_def_mutex;
42 	void			(*netlink_rcv)(struct sk_buff *skb);
43 	int			(*netlink_bind)(struct net *net, int group);
44 	void			(*netlink_unbind)(struct net *net, int group);
45 	struct module		*module;
46 
47 	struct rhash_head	node;
48 	struct rcu_head		rcu;
49 	struct work_struct	work;
50 };
51 
nlk_sk(struct sock * sk)52 static inline struct netlink_sock *nlk_sk(struct sock *sk)
53 {
54 	return container_of(sk, struct netlink_sock, sk);
55 }
56 
57 struct netlink_table {
58 	struct rhashtable	hash;
59 	struct hlist_head	mc_list;
60 	struct listeners __rcu	*listeners;
61 	unsigned int		flags;
62 	unsigned int		groups;
63 	struct mutex		*cb_mutex;
64 	struct module		*module;
65 	int			(*bind)(struct net *net, int group);
66 	void			(*unbind)(struct net *net, int group);
67 	bool			(*compare)(struct net *net, struct sock *sock);
68 	int			registered;
69 };
70 
71 extern struct netlink_table *nl_table;
72 extern rwlock_t nl_table_lock;
73 
74 #endif
75