xref: /linux/include/net/af_unix.h (revision e80a48bade619ec5a92230b3d4ae84bfc2746822)
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_MOD	(256 - 1)
20 #define UNIX_HASH_SIZE	(256 * 2)
21 #define UNIX_HASH_BITS	8
22 
23 extern unsigned int unix_tot_inflight;
24 
25 struct unix_address {
26 	refcount_t	refcnt;
27 	int		len;
28 	struct sockaddr_un name[];
29 };
30 
31 struct unix_skb_parms {
32 	struct pid		*pid;		/* Skb credentials	*/
33 	kuid_t			uid;
34 	kgid_t			gid;
35 	struct scm_fp_list	*fp;		/* Passed files		*/
36 #ifdef CONFIG_SECURITY_NETWORK
37 	u32			secid;		/* Security ID		*/
38 #endif
39 	u32			consumed;
40 } __randomize_layout;
41 
42 struct scm_stat {
43 	atomic_t nr_fds;
44 };
45 
46 #define UNIXCB(skb)	(*(struct unix_skb_parms *)&((skb)->cb))
47 
48 #define unix_state_lock(s)	spin_lock(&unix_sk(s)->lock)
49 #define unix_state_unlock(s)	spin_unlock(&unix_sk(s)->lock)
50 #define unix_state_lock_nested(s) \
51 				spin_lock_nested(&unix_sk(s)->lock, \
52 				SINGLE_DEPTH_NESTING)
53 
54 /* The AF_UNIX socket */
55 struct unix_sock {
56 	/* WARNING: sk has to be the first member */
57 	struct sock		sk;
58 	struct unix_address	*addr;
59 	struct path		path;
60 	struct mutex		iolock, bindlock;
61 	struct sock		*peer;
62 	struct list_head	link;
63 	atomic_long_t		inflight;
64 	spinlock_t		lock;
65 	unsigned long		gc_flags;
66 #define UNIX_GC_CANDIDATE	0
67 #define UNIX_GC_MAYBE_CYCLE	1
68 	struct socket_wq	peer_wq;
69 	wait_queue_entry_t	peer_wake;
70 	struct scm_stat		scm_stat;
71 #if IS_ENABLED(CONFIG_AF_UNIX_OOB)
72 	struct sk_buff		*oob_skb;
73 #endif
74 };
75 
76 static inline struct unix_sock *unix_sk(const struct sock *sk)
77 {
78 	return (struct unix_sock *)sk;
79 }
80 
81 #define peer_wait peer_wq.wait
82 
83 long unix_inq_len(struct sock *sk);
84 long unix_outq_len(struct sock *sk);
85 
86 int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
87 			 int flags);
88 int __unix_stream_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
89 			  int flags);
90 #ifdef CONFIG_SYSCTL
91 int unix_sysctl_register(struct net *net);
92 void unix_sysctl_unregister(struct net *net);
93 #else
94 static inline int unix_sysctl_register(struct net *net) { return 0; }
95 static inline void unix_sysctl_unregister(struct net *net) {}
96 #endif
97 
98 #ifdef CONFIG_BPF_SYSCALL
99 extern struct proto unix_dgram_proto;
100 extern struct proto unix_stream_proto;
101 
102 int unix_dgram_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
103 int unix_stream_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
104 void __init unix_bpf_build_proto(void);
105 #else
106 static inline void __init unix_bpf_build_proto(void)
107 {}
108 #endif
109 #endif
110