xref: /linux/include/net/af_unix.h (revision d8c6b3fc918dd7b93c66e49ff8640746b84fbfe9)
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 io_uring_destruct_scm(struct sk_buff *skb);
15 void unix_gc(void);
16 void wait_for_unix_gc(void);
17 struct sock *unix_get_socket(struct file *filp);
18 struct sock *unix_peer_get(struct sock *sk);
19 
20 #define UNIX_HASH_MOD	(256 - 1)
21 #define UNIX_HASH_SIZE	(256 * 2)
22 #define UNIX_HASH_BITS	8
23 
24 extern unsigned int unix_tot_inflight;
25 
26 struct unix_address {
27 	refcount_t	refcnt;
28 	int		len;
29 	struct sockaddr_un name[];
30 };
31 
32 struct unix_skb_parms {
33 	struct pid		*pid;		/* Skb credentials	*/
34 	kuid_t			uid;
35 	kgid_t			gid;
36 	struct scm_fp_list	*fp;		/* Passed files		*/
37 #ifdef CONFIG_SECURITY_NETWORK
38 	u32			secid;		/* Security ID		*/
39 #endif
40 	u32			consumed;
41 } __randomize_layout;
42 
43 struct scm_stat {
44 	atomic_t nr_fds;
45 };
46 
47 #define UNIXCB(skb)	(*(struct unix_skb_parms *)&((skb)->cb))
48 
49 #define unix_state_lock(s)	spin_lock(&unix_sk(s)->lock)
50 #define unix_state_unlock(s)	spin_unlock(&unix_sk(s)->lock)
51 #define unix_state_lock_nested(s) \
52 				spin_lock_nested(&unix_sk(s)->lock, \
53 				SINGLE_DEPTH_NESTING)
54 
55 /* The AF_UNIX socket */
56 struct unix_sock {
57 	/* WARNING: sk has to be the first member */
58 	struct sock		sk;
59 	struct unix_address	*addr;
60 	struct path		path;
61 	struct mutex		iolock, bindlock;
62 	struct sock		*peer;
63 	struct list_head	link;
64 	atomic_long_t		inflight;
65 	spinlock_t		lock;
66 	unsigned long		gc_flags;
67 #define UNIX_GC_CANDIDATE	0
68 #define UNIX_GC_MAYBE_CYCLE	1
69 	struct socket_wq	peer_wq;
70 	wait_queue_entry_t	peer_wake;
71 	struct scm_stat		scm_stat;
72 #if IS_ENABLED(CONFIG_AF_UNIX_OOB)
73 	struct sk_buff		*oob_skb;
74 #endif
75 };
76 
77 #define unix_sk(ptr) container_of_const(ptr, struct unix_sock, sk)
78 
79 #define peer_wait peer_wq.wait
80 
81 long unix_inq_len(struct sock *sk);
82 long unix_outq_len(struct sock *sk);
83 
84 int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
85 			 int flags);
86 int __unix_stream_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
87 			  int flags);
88 #ifdef CONFIG_SYSCTL
89 int unix_sysctl_register(struct net *net);
90 void unix_sysctl_unregister(struct net *net);
91 #else
92 static inline int unix_sysctl_register(struct net *net) { return 0; }
93 static inline void unix_sysctl_unregister(struct net *net) {}
94 #endif
95 
96 #ifdef CONFIG_BPF_SYSCALL
97 extern struct proto unix_dgram_proto;
98 extern struct proto unix_stream_proto;
99 
100 int unix_dgram_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
101 int unix_stream_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
102 void __init unix_bpf_build_proto(void);
103 #else
104 static inline void __init unix_bpf_build_proto(void)
105 {}
106 #endif
107 #endif
108