xref: /linux/include/net/af_unix.h (revision 4a24560ad72f8febfa4e11cad63fbf24ac94c008)
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 #if IS_ENABLED(CONFIG_UNIX)
12 struct unix_sock *unix_get_socket(struct file *filp);
13 #else
14 static inline struct unix_sock *unix_get_socket(struct file *filp)
15 {
16 	return NULL;
17 }
18 #endif
19 
20 void unix_inflight(struct user_struct *user, struct file *fp);
21 void unix_notinflight(struct user_struct *user, struct file *fp);
22 void unix_destruct_scm(struct sk_buff *skb);
23 void io_uring_destruct_scm(struct sk_buff *skb);
24 void unix_gc(void);
25 void wait_for_unix_gc(struct scm_fp_list *fpl);
26 struct sock *unix_peer_get(struct sock *sk);
27 
28 #define UNIX_HASH_MOD	(256 - 1)
29 #define UNIX_HASH_SIZE	(256 * 2)
30 #define UNIX_HASH_BITS	8
31 
32 extern unsigned int unix_tot_inflight;
33 
34 struct unix_address {
35 	refcount_t	refcnt;
36 	int		len;
37 	struct sockaddr_un name[];
38 };
39 
40 struct unix_skb_parms {
41 	struct pid		*pid;		/* Skb credentials	*/
42 	kuid_t			uid;
43 	kgid_t			gid;
44 	struct scm_fp_list	*fp;		/* Passed files		*/
45 #ifdef CONFIG_SECURITY_NETWORK
46 	u32			secid;		/* Security ID		*/
47 #endif
48 	u32			consumed;
49 } __randomize_layout;
50 
51 struct scm_stat {
52 	atomic_t nr_fds;
53 };
54 
55 #define UNIXCB(skb)	(*(struct unix_skb_parms *)&((skb)->cb))
56 
57 #define unix_state_lock(s)	spin_lock(&unix_sk(s)->lock)
58 #define unix_state_unlock(s)	spin_unlock(&unix_sk(s)->lock)
59 #define unix_state_lock_nested(s) \
60 				spin_lock_nested(&unix_sk(s)->lock, \
61 				SINGLE_DEPTH_NESTING)
62 
63 /* The AF_UNIX socket */
64 struct unix_sock {
65 	/* WARNING: sk has to be the first member */
66 	struct sock		sk;
67 	struct unix_address	*addr;
68 	struct path		path;
69 	struct mutex		iolock, bindlock;
70 	struct sock		*peer;
71 	struct list_head	link;
72 	unsigned long		inflight;
73 	spinlock_t		lock;
74 	unsigned long		gc_flags;
75 #define UNIX_GC_CANDIDATE	0
76 #define UNIX_GC_MAYBE_CYCLE	1
77 	struct socket_wq	peer_wq;
78 	wait_queue_entry_t	peer_wake;
79 	struct scm_stat		scm_stat;
80 #if IS_ENABLED(CONFIG_AF_UNIX_OOB)
81 	struct sk_buff		*oob_skb;
82 #endif
83 };
84 
85 #define unix_sk(ptr) container_of_const(ptr, struct unix_sock, sk)
86 #define unix_peer(sk) (unix_sk(sk)->peer)
87 
88 #define peer_wait peer_wq.wait
89 
90 long unix_inq_len(struct sock *sk);
91 long unix_outq_len(struct sock *sk);
92 
93 int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
94 			 int flags);
95 int __unix_stream_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
96 			  int flags);
97 #ifdef CONFIG_SYSCTL
98 int unix_sysctl_register(struct net *net);
99 void unix_sysctl_unregister(struct net *net);
100 #else
101 static inline int unix_sysctl_register(struct net *net) { return 0; }
102 static inline void unix_sysctl_unregister(struct net *net) {}
103 #endif
104 
105 #ifdef CONFIG_BPF_SYSCALL
106 extern struct proto unix_dgram_proto;
107 extern struct proto unix_stream_proto;
108 
109 int unix_dgram_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
110 int unix_stream_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
111 void __init unix_bpf_build_proto(void);
112 #else
113 static inline void __init unix_bpf_build_proto(void)
114 {}
115 #endif
116 #endif
117