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 <net/sock.h>
8
9 /* flags */
10 enum {
11 NETLINK_F_KERNEL_SOCKET,
12 NETLINK_F_RECV_PKTINFO,
13 NETLINK_F_BROADCAST_SEND_ERROR,
14 NETLINK_F_RECV_NO_ENOBUFS,
15 NETLINK_F_LISTEN_ALL_NSID,
16 NETLINK_F_CAP_ACK,
17 NETLINK_F_EXT_ACK,
18 NETLINK_F_STRICT_CHK,
19 };
20
21 #define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8)
22 #define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long))
23
24 struct netlink_sock {
25 /* struct sock has to be the first member of netlink_sock */
26 struct sock sk;
27 unsigned long flags;
28 u32 portid;
29 u32 dst_portid;
30 u32 dst_group;
31 u32 subscriptions;
32 u32 ngroups;
33 unsigned long *groups;
34 unsigned long state;
35 size_t max_recvmsg_len;
36 wait_queue_head_t wait;
37 bool bound;
38 bool cb_running;
39 int dump_done_errno;
40 struct netlink_callback cb;
41 struct mutex nl_cb_mutex;
42
43 void (*netlink_rcv)(struct sk_buff *skb);
44 int (*netlink_bind)(struct net *net, int group);
45 void (*netlink_unbind)(struct net *net, int group);
46 void (*netlink_release)(struct sock *sk,
47 unsigned long *groups);
48 struct module *module;
49
50 struct rhash_head node;
51 struct rcu_head rcu;
52 };
53
nlk_sk(struct sock * sk)54 static inline struct netlink_sock *nlk_sk(struct sock *sk)
55 {
56 return container_of(sk, struct netlink_sock, sk);
57 }
58
59 #define nlk_test_bit(nr, sk) test_bit(NETLINK_F_##nr, &nlk_sk(sk)->flags)
60
61 struct netlink_table {
62 struct rhashtable hash;
63 struct hlist_head mc_list;
64 struct listeners __rcu *listeners;
65 unsigned int flags;
66 unsigned int groups;
67 struct mutex *cb_mutex;
68 struct module *module;
69 int (*bind)(struct net *net, int group);
70 void (*unbind)(struct net *net, int group);
71 void (*release)(struct sock *sk,
72 unsigned long *groups);
73 int registered;
74 };
75
76 extern struct netlink_table *nl_table;
77 extern rwlock_t nl_table_lock;
78
79 #endif
80