xref: /openbmc/linux/include/net/af_unix.h (revision 753a277e)
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 /* The AF_UNIX socket */
50 struct unix_sock {
51 	/* WARNING: sk has to be the first member */
52 	struct sock		sk;
53 	struct unix_address	*addr;
54 	struct path		path;
55 	struct mutex		iolock, bindlock;
56 	struct sock		*peer;
57 	struct list_head	link;
58 	unsigned long		inflight;
59 	spinlock_t		lock;
60 	unsigned long		gc_flags;
61 #define UNIX_GC_CANDIDATE	0
62 #define UNIX_GC_MAYBE_CYCLE	1
63 	struct socket_wq	peer_wq;
64 	wait_queue_entry_t	peer_wake;
65 	struct scm_stat		scm_stat;
66 #if IS_ENABLED(CONFIG_AF_UNIX_OOB)
67 	struct sk_buff		*oob_skb;
68 #endif
69 };
70 
71 #define unix_sk(ptr) container_of_const(ptr, struct unix_sock, sk)
72 #define unix_peer(sk) (unix_sk(sk)->peer)
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)
76 enum 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 	U_LOCK_GC_LISTENER, /* used for listening socket while determining gc
81 			     * candidates to close a small race window.
82 			     */
83 };
84 
unix_state_lock_nested(struct sock * sk,enum unix_socket_lock_class subclass)85 static inline void unix_state_lock_nested(struct sock *sk,
86 				   enum unix_socket_lock_class subclass)
87 {
88 	spin_lock_nested(&unix_sk(sk)->lock, subclass);
89 }
90 
91 #define peer_wait peer_wq.wait
92 
93 long unix_inq_len(struct sock *sk);
94 long unix_outq_len(struct sock *sk);
95 
96 int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
97 			 int flags);
98 int __unix_stream_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
99 			  int flags);
100 #ifdef CONFIG_SYSCTL
101 int unix_sysctl_register(struct net *net);
102 void unix_sysctl_unregister(struct net *net);
103 #else
unix_sysctl_register(struct net * net)104 static inline int unix_sysctl_register(struct net *net) { return 0; }
unix_sysctl_unregister(struct net * net)105 static inline void unix_sysctl_unregister(struct net *net) {}
106 #endif
107 
108 #ifdef CONFIG_BPF_SYSCALL
109 extern struct proto unix_dgram_proto;
110 extern struct proto unix_stream_proto;
111 
112 int unix_dgram_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
113 int unix_stream_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
114 void __init unix_bpf_build_proto(void);
115 #else
unix_bpf_build_proto(void)116 static inline void __init unix_bpf_build_proto(void)
117 {}
118 #endif
119 #endif
120