include/net/af_unix.h

   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 extern spinlock_t unix_gc_lock;
  21 extern unsigned int unix_tot_inflight;
  22
  23 void unix_inflight(struct user_struct *user, struct file *fp);
  24 void unix_notinflight(struct user_struct *user, struct file *fp);
  25 void unix_gc(void);
  26 void wait_for_unix_gc(struct scm_fp_list *fpl);
  27
  28 struct sock *unix_peer_get(struct sock *sk);
  29
  30 #define UNIX_HASH_MOD   (256 - 1)
  31 #define UNIX_HASH_SIZE  (256 * 2)
  32 #define UNIX_HASH_BITS  8
  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 /* The AF_UNIX socket */
  58 struct unix_sock {
  59         /* WARNING: sk has to be the first member */
  60         struct sock             sk;
  61         struct unix_address     *addr;
  62         struct path             path;
  63         struct mutex            iolock, bindlock;
  64         struct sock             *peer;
  65         struct list_head        link;
  66         unsigned long           inflight;
  67         spinlock_t              lock;
  68         unsigned long           gc_flags;
  69 #define UNIX_GC_CANDIDATE       0
  70 #define UNIX_GC_MAYBE_CYCLE     1
  71         struct socket_wq        peer_wq;
  72         wait_queue_entry_t      peer_wake;
  73         struct scm_stat         scm_stat;
  74 #if IS_ENABLED(CONFIG_AF_UNIX_OOB)
  75         struct sk_buff          *oob_skb;
  76 #endif
  77 };
  78
  79 #define unix_sk(ptr) container_of_const(ptr, struct unix_sock, sk)
  80 #define unix_peer(sk) (unix_sk(sk)->peer)
  81
  82 #define unix_state_lock(s)      spin_lock(&unix_sk(s)->lock)
  83 #define unix_state_unlock(s)    spin_unlock(&unix_sk(s)->lock)
  84 enum unix_socket_lock_class {
  85         U_LOCK_NORMAL,
  86         U_LOCK_SECOND,  /* for double locking, see unix_state_double_lock(). */
  87         U_LOCK_DIAG, /* used while dumping icons, see sk_diag_dump_icons(). */
  88 };
  89
  90 static inline void unix_state_lock_nested(struct sock *sk,
  91                                    enum unix_socket_lock_class subclass)
  92 {
  93         spin_lock_nested(&unix_sk(sk)->lock, subclass);
  94 }
  95
  96 #define peer_wait peer_wq.wait
  97
  98 long unix_inq_len(struct sock *sk);
  99 long unix_outq_len(struct sock *sk);
 100
 101 int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
 102                          int flags);
 103 int __unix_stream_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
 104                           int flags);
 105 #ifdef CONFIG_SYSCTL
 106 int unix_sysctl_register(struct net *net);
 107 void unix_sysctl_unregister(struct net *net);
 108 #else
 109 static inline int unix_sysctl_register(struct net *net) { return 0; }
 110 static inline void unix_sysctl_unregister(struct net *net) {}
 111 #endif
 112
 113 #ifdef CONFIG_BPF_SYSCALL
 114 extern struct proto unix_dgram_proto;
 115 extern struct proto unix_stream_proto;
 116
 117 int unix_dgram_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
 118 int unix_stream_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
 119 void __init unix_bpf_build_proto(void);
 120 #else
 121 static inline void __init unix_bpf_build_proto(void)
 122 {}
 123 #endif
 124 #endif