xref: /linux/include/net/af_unix.h (revision 24ce659dcc02c21f8d6c0a7589c3320a4dfa8152)
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 
11 void unix_inflight(struct user_struct *user, struct file *fp);
12 void unix_notinflight(struct user_struct *user, struct file *fp);
13 void unix_destruct_scm(struct sk_buff *skb);
14 void unix_gc(void);
15 void wait_for_unix_gc(void);
16 struct sock *unix_get_socket(struct file *filp);
17 struct sock *unix_peer_get(struct sock *sk);
18 
19 #define UNIX_HASH_SIZE	256
20 #define UNIX_HASH_BITS	8
21 
22 extern unsigned int unix_tot_inflight;
23 extern spinlock_t unix_table_lock;
24 extern struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE];
25 
26 struct unix_address {
27 	refcount_t	refcnt;
28 	int		len;
29 	unsigned int	hash;
30 	struct sockaddr_un name[];
31 };
32 
33 struct 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 
44 struct scm_stat {
45 	atomic_t nr_fds;
46 };
47 
48 #define UNIXCB(skb)	(*(struct unix_skb_parms *)&((skb)->cb))
49 
50 #define unix_state_lock(s)	spin_lock(&unix_sk(s)->lock)
51 #define unix_state_unlock(s)	spin_unlock(&unix_sk(s)->lock)
52 #define unix_state_lock_nested(s) \
53 				spin_lock_nested(&unix_sk(s)->lock, \
54 				SINGLE_DEPTH_NESTING)
55 
56 /* The AF_UNIX socket */
57 struct unix_sock {
58 	/* WARNING: sk has to be the first member */
59 	struct sock		sk;
60 	struct unix_address	*addr;
61 	struct path		path;
62 	struct mutex		iolock, bindlock;
63 	struct sock		*peer;
64 	struct list_head	link;
65 	atomic_long_t		inflight;
66 	spinlock_t		lock;
67 	unsigned long		gc_flags;
68 #define UNIX_GC_CANDIDATE	0
69 #define UNIX_GC_MAYBE_CYCLE	1
70 	struct socket_wq	peer_wq;
71 	wait_queue_entry_t	peer_wake;
72 	struct scm_stat		scm_stat;
73 };
74 
75 static inline struct unix_sock *unix_sk(const struct sock *sk)
76 {
77 	return (struct unix_sock *)sk;
78 }
79 
80 #define peer_wait peer_wq.wait
81 
82 long unix_inq_len(struct sock *sk);
83 long unix_outq_len(struct sock *sk);
84 
85 #ifdef CONFIG_SYSCTL
86 int unix_sysctl_register(struct net *net);
87 void unix_sysctl_unregister(struct net *net);
88 #else
89 static inline int unix_sysctl_register(struct net *net) { return 0; }
90 static inline void unix_sysctl_unregister(struct net *net) {}
91 #endif
92 #endif
93