xref: /kernel/linux/linux-5.10/include/net/af_unix.h (revision 8c2ecf20)
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_NET_AFUNIX_H
3#define __LINUX_NET_AFUNIX_H
4
5#include <linux/socket.h>
6#include <linux/un.h>
7#include <linux/mutex.h>
8#include <linux/refcount.h>
9#include <net/sock.h>
10
11void unix_inflight(struct user_struct *user, struct file *fp);
12void unix_notinflight(struct user_struct *user, struct file *fp);
13void unix_destruct_scm(struct sk_buff *skb);
14void unix_gc(void);
15void wait_for_unix_gc(void);
16struct sock *unix_get_socket(struct file *filp);
17struct sock *unix_peer_get(struct sock *sk);
18
19#define UNIX_HASH_SIZE	256
20#define UNIX_HASH_BITS	8
21
22extern unsigned int unix_tot_inflight;
23extern spinlock_t unix_table_lock;
24extern struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE];
25
26struct unix_address {
27	refcount_t	refcnt;
28	int		len;
29	unsigned int	hash;
30	struct sockaddr_un name[];
31};
32
33struct unix_skb_parms {
34	struct pid		*pid;		/* Skb credentials	*/
35	kuid_t			uid;
36	kgid_t			gid;
37	struct scm_fp_list	*fp;		/* Passed files		*/
38#ifdef CONFIG_SECURITY_NETWORK
39	u32			secid;		/* Security ID		*/
40#endif
41	u32			consumed;
42} __randomize_layout;
43
44struct scm_stat {
45	atomic_t nr_fds;
46};
47
48#define UNIXCB(skb)	(*(struct unix_skb_parms *)&((skb)->cb))
49
50/* The AF_UNIX socket */
51struct unix_sock {
52	/* WARNING: sk has to be the first member */
53	struct sock		sk;
54	struct unix_address	*addr;
55	struct path		path;
56	struct mutex		iolock, bindlock;
57	struct sock		*peer;
58	struct list_head	link;
59	atomic_long_t		inflight;
60	spinlock_t		lock;
61	unsigned long		gc_flags;
62#define UNIX_GC_CANDIDATE	0
63#define UNIX_GC_MAYBE_CYCLE	1
64	struct socket_wq	peer_wq;
65	wait_queue_entry_t	peer_wake;
66	struct scm_stat		scm_stat;
67};
68
69static inline struct unix_sock *unix_sk(const struct sock *sk)
70{
71	return (struct unix_sock *)sk;
72}
73
74#define unix_state_lock(s)	spin_lock(&unix_sk(s)->lock)
75#define unix_state_unlock(s)	spin_unlock(&unix_sk(s)->lock)
76enum unix_socket_lock_class {
77	U_LOCK_NORMAL,
78	U_LOCK_SECOND,	/* for double locking, see unix_state_double_lock(). */
79	U_LOCK_DIAG, /* used while dumping icons, see sk_diag_dump_icons(). */
80};
81
82static inline void unix_state_lock_nested(struct sock *sk,
83				   enum unix_socket_lock_class subclass)
84{
85	spin_lock_nested(&unix_sk(sk)->lock, subclass);
86}
87
88#define peer_wait peer_wq.wait
89
90long unix_inq_len(struct sock *sk);
91long unix_outq_len(struct sock *sk);
92
93#ifdef CONFIG_SYSCTL
94int unix_sysctl_register(struct net *net);
95void unix_sysctl_unregister(struct net *net);
96#else
97static inline int unix_sysctl_register(struct net *net) { return 0; }
98static inline void unix_sysctl_unregister(struct net *net) {}
99#endif
100#endif
101