Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * NET4: Implementation of BSD Unix domain sockets. | |
3 | * | |
113aa838 | 4 | * Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> |
1da177e4 LT |
5 | * |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
1da177e4 LT |
11 | * Fixes: |
12 | * Linus Torvalds : Assorted bug cures. | |
13 | * Niibe Yutaka : async I/O support. | |
14 | * Carsten Paeth : PF_UNIX check, address fixes. | |
15 | * Alan Cox : Limit size of allocated blocks. | |
16 | * Alan Cox : Fixed the stupid socketpair bug. | |
17 | * Alan Cox : BSD compatibility fine tuning. | |
18 | * Alan Cox : Fixed a bug in connect when interrupted. | |
19 | * Alan Cox : Sorted out a proper draft version of | |
20 | * file descriptor passing hacked up from | |
21 | * Mike Shaver's work. | |
22 | * Marty Leisner : Fixes to fd passing | |
23 | * Nick Nevin : recvmsg bugfix. | |
24 | * Alan Cox : Started proper garbage collector | |
25 | * Heiko EiBfeldt : Missing verify_area check | |
26 | * Alan Cox : Started POSIXisms | |
27 | * Andreas Schwab : Replace inode by dentry for proper | |
28 | * reference counting | |
29 | * Kirk Petersen : Made this a module | |
30 | * Christoph Rohland : Elegant non-blocking accept/connect algorithm. | |
31 | * Lots of bug fixes. | |
32 | * Alexey Kuznetosv : Repaired (I hope) bugs introduces | |
33 | * by above two patches. | |
34 | * Andrea Arcangeli : If possible we block in connect(2) | |
35 | * if the max backlog of the listen socket | |
36 | * is been reached. This won't break | |
37 | * old apps and it will avoid huge amount | |
38 | * of socks hashed (this for unix_gc() | |
39 | * performances reasons). | |
40 | * Security fix that limits the max | |
41 | * number of socks to 2*max_files and | |
42 | * the number of skb queueable in the | |
43 | * dgram receiver. | |
44 | * Artur Skawina : Hash function optimizations | |
45 | * Alexey Kuznetsov : Full scale SMP. Lot of bugs are introduced 8) | |
46 | * Malcolm Beattie : Set peercred for socketpair | |
47 | * Michal Ostrowski : Module initialization cleanup. | |
48 | * Arnaldo C. Melo : Remove MOD_{INC,DEC}_USE_COUNT, | |
49 | * the core infrastructure is doing that | |
50 | * for all net proto families now (2.5.69+) | |
51 | * | |
52 | * | |
53 | * Known differences from reference BSD that was tested: | |
54 | * | |
55 | * [TO FIX] | |
56 | * ECONNREFUSED is not returned from one end of a connected() socket to the | |
57 | * other the moment one end closes. | |
58 | * fstat() doesn't return st_dev=0, and give the blksize as high water mark | |
59 | * and a fake inode identifier (nor the BSD first socket fstat twice bug). | |
60 | * [NOT TO FIX] | |
61 | * accept() returns a path name even if the connecting socket has closed | |
62 | * in the meantime (BSD loses the path and gives up). | |
63 | * accept() returns 0 length path for an unbound connector. BSD returns 16 | |
64 | * and a null first byte in the path (but not for gethost/peername - BSD bug ??) | |
65 | * socketpair(...SOCK_RAW..) doesn't panic the kernel. | |
66 | * BSD af_unix apparently has connect forgetting to block properly. | |
67 | * (need to check this with the POSIX spec in detail) | |
68 | * | |
69 | * Differences from 2.0.0-11-... (ANK) | |
70 | * Bug fixes and improvements. | |
71 | * - client shutdown killed server socket. | |
72 | * - removed all useless cli/sti pairs. | |
73 | * | |
74 | * Semantic changes/extensions. | |
75 | * - generic control message passing. | |
76 | * - SCM_CREDENTIALS control message. | |
77 | * - "Abstract" (not FS based) socket bindings. | |
78 | * Abstract names are sequences of bytes (not zero terminated) | |
79 | * started by 0, so that this name space does not intersect | |
80 | * with BSD names. | |
81 | */ | |
82 | ||
83 | #include <linux/module.h> | |
1da177e4 | 84 | #include <linux/kernel.h> |
1da177e4 LT |
85 | #include <linux/signal.h> |
86 | #include <linux/sched.h> | |
87 | #include <linux/errno.h> | |
88 | #include <linux/string.h> | |
89 | #include <linux/stat.h> | |
90 | #include <linux/dcache.h> | |
91 | #include <linux/namei.h> | |
92 | #include <linux/socket.h> | |
93 | #include <linux/un.h> | |
94 | #include <linux/fcntl.h> | |
95 | #include <linux/termios.h> | |
96 | #include <linux/sockios.h> | |
97 | #include <linux/net.h> | |
98 | #include <linux/in.h> | |
99 | #include <linux/fs.h> | |
100 | #include <linux/slab.h> | |
101 | #include <asm/uaccess.h> | |
102 | #include <linux/skbuff.h> | |
103 | #include <linux/netdevice.h> | |
457c4cbc | 104 | #include <net/net_namespace.h> |
1da177e4 | 105 | #include <net/sock.h> |
c752f073 | 106 | #include <net/tcp_states.h> |
1da177e4 LT |
107 | #include <net/af_unix.h> |
108 | #include <linux/proc_fs.h> | |
109 | #include <linux/seq_file.h> | |
110 | #include <net/scm.h> | |
111 | #include <linux/init.h> | |
112 | #include <linux/poll.h> | |
1da177e4 LT |
113 | #include <linux/rtnetlink.h> |
114 | #include <linux/mount.h> | |
115 | #include <net/checksum.h> | |
116 | #include <linux/security.h> | |
117 | ||
13111698 AB |
118 | static struct hlist_head unix_socket_table[UNIX_HASH_SIZE + 1]; |
119 | static DEFINE_SPINLOCK(unix_table_lock); | |
518de9b3 | 120 | static atomic_long_t unix_nr_socks; |
1da177e4 LT |
121 | |
122 | #define unix_sockets_unbound (&unix_socket_table[UNIX_HASH_SIZE]) | |
123 | ||
124 | #define UNIX_ABSTRACT(sk) (unix_sk(sk)->addr->hash != UNIX_HASH_SIZE) | |
125 | ||
877ce7c1 | 126 | #ifdef CONFIG_SECURITY_NETWORK |
dc49c1f9 | 127 | static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 | 128 | { |
dc49c1f9 | 129 | memcpy(UNIXSID(skb), &scm->secid, sizeof(u32)); |
877ce7c1 CZ |
130 | } |
131 | ||
132 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
133 | { | |
dc49c1f9 | 134 | scm->secid = *UNIXSID(skb); |
877ce7c1 CZ |
135 | } |
136 | #else | |
dc49c1f9 | 137 | static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 CZ |
138 | { } |
139 | ||
140 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
141 | { } | |
142 | #endif /* CONFIG_SECURITY_NETWORK */ | |
143 | ||
1da177e4 LT |
144 | /* |
145 | * SMP locking strategy: | |
fbe9cc4a | 146 | * hash table is protected with spinlock unix_table_lock |
663717f6 | 147 | * each socket state is protected by separate spin lock. |
1da177e4 LT |
148 | */ |
149 | ||
44bb9363 | 150 | static inline unsigned unix_hash_fold(__wsum n) |
1da177e4 | 151 | { |
44bb9363 | 152 | unsigned hash = (__force unsigned)n; |
1da177e4 LT |
153 | hash ^= hash>>16; |
154 | hash ^= hash>>8; | |
155 | return hash&(UNIX_HASH_SIZE-1); | |
156 | } | |
157 | ||
158 | #define unix_peer(sk) (unix_sk(sk)->peer) | |
159 | ||
160 | static inline int unix_our_peer(struct sock *sk, struct sock *osk) | |
161 | { | |
162 | return unix_peer(osk) == sk; | |
163 | } | |
164 | ||
165 | static inline int unix_may_send(struct sock *sk, struct sock *osk) | |
166 | { | |
6eba6a37 | 167 | return unix_peer(osk) == NULL || unix_our_peer(sk, osk); |
1da177e4 LT |
168 | } |
169 | ||
3c73419c RW |
170 | static inline int unix_recvq_full(struct sock const *sk) |
171 | { | |
172 | return skb_queue_len(&sk->sk_receive_queue) > sk->sk_max_ack_backlog; | |
173 | } | |
174 | ||
1da177e4 LT |
175 | static struct sock *unix_peer_get(struct sock *s) |
176 | { | |
177 | struct sock *peer; | |
178 | ||
1c92b4e5 | 179 | unix_state_lock(s); |
1da177e4 LT |
180 | peer = unix_peer(s); |
181 | if (peer) | |
182 | sock_hold(peer); | |
1c92b4e5 | 183 | unix_state_unlock(s); |
1da177e4 LT |
184 | return peer; |
185 | } | |
186 | ||
187 | static inline void unix_release_addr(struct unix_address *addr) | |
188 | { | |
189 | if (atomic_dec_and_test(&addr->refcnt)) | |
190 | kfree(addr); | |
191 | } | |
192 | ||
193 | /* | |
194 | * Check unix socket name: | |
195 | * - should be not zero length. | |
196 | * - if started by not zero, should be NULL terminated (FS object) | |
197 | * - if started by zero, it is abstract name. | |
198 | */ | |
ac7bfa62 | 199 | |
6eba6a37 | 200 | static int unix_mkname(struct sockaddr_un *sunaddr, int len, unsigned *hashp) |
1da177e4 LT |
201 | { |
202 | if (len <= sizeof(short) || len > sizeof(*sunaddr)) | |
203 | return -EINVAL; | |
204 | if (!sunaddr || sunaddr->sun_family != AF_UNIX) | |
205 | return -EINVAL; | |
206 | if (sunaddr->sun_path[0]) { | |
207 | /* | |
208 | * This may look like an off by one error but it is a bit more | |
209 | * subtle. 108 is the longest valid AF_UNIX path for a binding. | |
210 | * sun_path[108] doesnt as such exist. However in kernel space | |
211 | * we are guaranteed that it is a valid memory location in our | |
212 | * kernel address buffer. | |
213 | */ | |
e27dfcea | 214 | ((char *)sunaddr)[len] = 0; |
1da177e4 LT |
215 | len = strlen(sunaddr->sun_path)+1+sizeof(short); |
216 | return len; | |
217 | } | |
218 | ||
07f0757a | 219 | *hashp = unix_hash_fold(csum_partial(sunaddr, len, 0)); |
1da177e4 LT |
220 | return len; |
221 | } | |
222 | ||
223 | static void __unix_remove_socket(struct sock *sk) | |
224 | { | |
225 | sk_del_node_init(sk); | |
226 | } | |
227 | ||
228 | static void __unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
229 | { | |
547b792c | 230 | WARN_ON(!sk_unhashed(sk)); |
1da177e4 LT |
231 | sk_add_node(sk, list); |
232 | } | |
233 | ||
234 | static inline void unix_remove_socket(struct sock *sk) | |
235 | { | |
fbe9cc4a | 236 | spin_lock(&unix_table_lock); |
1da177e4 | 237 | __unix_remove_socket(sk); |
fbe9cc4a | 238 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
239 | } |
240 | ||
241 | static inline void unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
242 | { | |
fbe9cc4a | 243 | spin_lock(&unix_table_lock); |
1da177e4 | 244 | __unix_insert_socket(list, sk); |
fbe9cc4a | 245 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
246 | } |
247 | ||
097e66c5 DL |
248 | static struct sock *__unix_find_socket_byname(struct net *net, |
249 | struct sockaddr_un *sunname, | |
1da177e4 LT |
250 | int len, int type, unsigned hash) |
251 | { | |
252 | struct sock *s; | |
253 | struct hlist_node *node; | |
254 | ||
255 | sk_for_each(s, node, &unix_socket_table[hash ^ type]) { | |
256 | struct unix_sock *u = unix_sk(s); | |
257 | ||
878628fb | 258 | if (!net_eq(sock_net(s), net)) |
097e66c5 DL |
259 | continue; |
260 | ||
1da177e4 LT |
261 | if (u->addr->len == len && |
262 | !memcmp(u->addr->name, sunname, len)) | |
263 | goto found; | |
264 | } | |
265 | s = NULL; | |
266 | found: | |
267 | return s; | |
268 | } | |
269 | ||
097e66c5 DL |
270 | static inline struct sock *unix_find_socket_byname(struct net *net, |
271 | struct sockaddr_un *sunname, | |
1da177e4 LT |
272 | int len, int type, |
273 | unsigned hash) | |
274 | { | |
275 | struct sock *s; | |
276 | ||
fbe9cc4a | 277 | spin_lock(&unix_table_lock); |
097e66c5 | 278 | s = __unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
279 | if (s) |
280 | sock_hold(s); | |
fbe9cc4a | 281 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
282 | return s; |
283 | } | |
284 | ||
6616f788 | 285 | static struct sock *unix_find_socket_byinode(struct inode *i) |
1da177e4 LT |
286 | { |
287 | struct sock *s; | |
288 | struct hlist_node *node; | |
289 | ||
fbe9cc4a | 290 | spin_lock(&unix_table_lock); |
1da177e4 LT |
291 | sk_for_each(s, node, |
292 | &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) { | |
293 | struct dentry *dentry = unix_sk(s)->dentry; | |
294 | ||
6eba6a37 | 295 | if (dentry && dentry->d_inode == i) { |
1da177e4 LT |
296 | sock_hold(s); |
297 | goto found; | |
298 | } | |
299 | } | |
300 | s = NULL; | |
301 | found: | |
fbe9cc4a | 302 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
303 | return s; |
304 | } | |
305 | ||
306 | static inline int unix_writable(struct sock *sk) | |
307 | { | |
308 | return (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf; | |
309 | } | |
310 | ||
311 | static void unix_write_space(struct sock *sk) | |
312 | { | |
43815482 ED |
313 | struct socket_wq *wq; |
314 | ||
315 | rcu_read_lock(); | |
1da177e4 | 316 | if (unix_writable(sk)) { |
43815482 ED |
317 | wq = rcu_dereference(sk->sk_wq); |
318 | if (wq_has_sleeper(wq)) | |
67426b75 ED |
319 | wake_up_interruptible_sync_poll(&wq->wait, |
320 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
8d8ad9d7 | 321 | sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); |
1da177e4 | 322 | } |
43815482 | 323 | rcu_read_unlock(); |
1da177e4 LT |
324 | } |
325 | ||
326 | /* When dgram socket disconnects (or changes its peer), we clear its receive | |
327 | * queue of packets arrived from previous peer. First, it allows to do | |
328 | * flow control based only on wmem_alloc; second, sk connected to peer | |
329 | * may receive messages only from that peer. */ | |
330 | static void unix_dgram_disconnected(struct sock *sk, struct sock *other) | |
331 | { | |
b03efcfb | 332 | if (!skb_queue_empty(&sk->sk_receive_queue)) { |
1da177e4 LT |
333 | skb_queue_purge(&sk->sk_receive_queue); |
334 | wake_up_interruptible_all(&unix_sk(sk)->peer_wait); | |
335 | ||
336 | /* If one link of bidirectional dgram pipe is disconnected, | |
337 | * we signal error. Messages are lost. Do not make this, | |
338 | * when peer was not connected to us. | |
339 | */ | |
340 | if (!sock_flag(other, SOCK_DEAD) && unix_peer(other) == sk) { | |
341 | other->sk_err = ECONNRESET; | |
342 | other->sk_error_report(other); | |
343 | } | |
344 | } | |
345 | } | |
346 | ||
347 | static void unix_sock_destructor(struct sock *sk) | |
348 | { | |
349 | struct unix_sock *u = unix_sk(sk); | |
350 | ||
351 | skb_queue_purge(&sk->sk_receive_queue); | |
352 | ||
547b792c IJ |
353 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); |
354 | WARN_ON(!sk_unhashed(sk)); | |
355 | WARN_ON(sk->sk_socket); | |
1da177e4 | 356 | if (!sock_flag(sk, SOCK_DEAD)) { |
6b41e7dd | 357 | printk(KERN_INFO "Attempt to release alive unix socket: %p\n", sk); |
1da177e4 LT |
358 | return; |
359 | } | |
360 | ||
361 | if (u->addr) | |
362 | unix_release_addr(u->addr); | |
363 | ||
518de9b3 | 364 | atomic_long_dec(&unix_nr_socks); |
6f756a8c | 365 | local_bh_disable(); |
a8076d8d | 366 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); |
6f756a8c | 367 | local_bh_enable(); |
1da177e4 | 368 | #ifdef UNIX_REFCNT_DEBUG |
518de9b3 ED |
369 | printk(KERN_DEBUG "UNIX %p is destroyed, %ld are still alive.\n", sk, |
370 | atomic_long_read(&unix_nr_socks)); | |
1da177e4 LT |
371 | #endif |
372 | } | |
373 | ||
6eba6a37 | 374 | static int unix_release_sock(struct sock *sk, int embrion) |
1da177e4 LT |
375 | { |
376 | struct unix_sock *u = unix_sk(sk); | |
377 | struct dentry *dentry; | |
378 | struct vfsmount *mnt; | |
379 | struct sock *skpair; | |
380 | struct sk_buff *skb; | |
381 | int state; | |
382 | ||
383 | unix_remove_socket(sk); | |
384 | ||
385 | /* Clear state */ | |
1c92b4e5 | 386 | unix_state_lock(sk); |
1da177e4 LT |
387 | sock_orphan(sk); |
388 | sk->sk_shutdown = SHUTDOWN_MASK; | |
389 | dentry = u->dentry; | |
390 | u->dentry = NULL; | |
391 | mnt = u->mnt; | |
392 | u->mnt = NULL; | |
393 | state = sk->sk_state; | |
394 | sk->sk_state = TCP_CLOSE; | |
1c92b4e5 | 395 | unix_state_unlock(sk); |
1da177e4 LT |
396 | |
397 | wake_up_interruptible_all(&u->peer_wait); | |
398 | ||
e27dfcea | 399 | skpair = unix_peer(sk); |
1da177e4 | 400 | |
e27dfcea | 401 | if (skpair != NULL) { |
1da177e4 | 402 | if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) { |
1c92b4e5 | 403 | unix_state_lock(skpair); |
1da177e4 LT |
404 | /* No more writes */ |
405 | skpair->sk_shutdown = SHUTDOWN_MASK; | |
406 | if (!skb_queue_empty(&sk->sk_receive_queue) || embrion) | |
407 | skpair->sk_err = ECONNRESET; | |
1c92b4e5 | 408 | unix_state_unlock(skpair); |
1da177e4 | 409 | skpair->sk_state_change(skpair); |
8d8ad9d7 | 410 | sk_wake_async(skpair, SOCK_WAKE_WAITD, POLL_HUP); |
1da177e4 LT |
411 | } |
412 | sock_put(skpair); /* It may now die */ | |
413 | unix_peer(sk) = NULL; | |
414 | } | |
415 | ||
416 | /* Try to flush out this socket. Throw out buffers at least */ | |
417 | ||
418 | while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { | |
e27dfcea | 419 | if (state == TCP_LISTEN) |
1da177e4 LT |
420 | unix_release_sock(skb->sk, 1); |
421 | /* passed fds are erased in the kfree_skb hook */ | |
422 | kfree_skb(skb); | |
423 | } | |
424 | ||
425 | if (dentry) { | |
426 | dput(dentry); | |
427 | mntput(mnt); | |
428 | } | |
429 | ||
430 | sock_put(sk); | |
431 | ||
432 | /* ---- Socket is dead now and most probably destroyed ---- */ | |
433 | ||
434 | /* | |
435 | * Fixme: BSD difference: In BSD all sockets connected to use get | |
436 | * ECONNRESET and we die on the spot. In Linux we behave | |
437 | * like files and pipes do and wait for the last | |
438 | * dereference. | |
439 | * | |
440 | * Can't we simply set sock->err? | |
441 | * | |
442 | * What the above comment does talk about? --ANK(980817) | |
443 | */ | |
444 | ||
9305cfa4 | 445 | if (unix_tot_inflight) |
ac7bfa62 | 446 | unix_gc(); /* Garbage collect fds */ |
1da177e4 LT |
447 | |
448 | return 0; | |
449 | } | |
450 | ||
109f6e39 EB |
451 | static void init_peercred(struct sock *sk) |
452 | { | |
453 | put_pid(sk->sk_peer_pid); | |
454 | if (sk->sk_peer_cred) | |
455 | put_cred(sk->sk_peer_cred); | |
456 | sk->sk_peer_pid = get_pid(task_tgid(current)); | |
457 | sk->sk_peer_cred = get_current_cred(); | |
458 | } | |
459 | ||
460 | static void copy_peercred(struct sock *sk, struct sock *peersk) | |
461 | { | |
462 | put_pid(sk->sk_peer_pid); | |
463 | if (sk->sk_peer_cred) | |
464 | put_cred(sk->sk_peer_cred); | |
465 | sk->sk_peer_pid = get_pid(peersk->sk_peer_pid); | |
466 | sk->sk_peer_cred = get_cred(peersk->sk_peer_cred); | |
467 | } | |
468 | ||
1da177e4 LT |
469 | static int unix_listen(struct socket *sock, int backlog) |
470 | { | |
471 | int err; | |
472 | struct sock *sk = sock->sk; | |
473 | struct unix_sock *u = unix_sk(sk); | |
109f6e39 EB |
474 | struct pid *old_pid = NULL; |
475 | const struct cred *old_cred = NULL; | |
1da177e4 LT |
476 | |
477 | err = -EOPNOTSUPP; | |
6eba6a37 ED |
478 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
479 | goto out; /* Only stream/seqpacket sockets accept */ | |
1da177e4 LT |
480 | err = -EINVAL; |
481 | if (!u->addr) | |
6eba6a37 | 482 | goto out; /* No listens on an unbound socket */ |
1c92b4e5 | 483 | unix_state_lock(sk); |
1da177e4 LT |
484 | if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN) |
485 | goto out_unlock; | |
486 | if (backlog > sk->sk_max_ack_backlog) | |
487 | wake_up_interruptible_all(&u->peer_wait); | |
488 | sk->sk_max_ack_backlog = backlog; | |
489 | sk->sk_state = TCP_LISTEN; | |
490 | /* set credentials so connect can copy them */ | |
109f6e39 | 491 | init_peercred(sk); |
1da177e4 LT |
492 | err = 0; |
493 | ||
494 | out_unlock: | |
1c92b4e5 | 495 | unix_state_unlock(sk); |
109f6e39 EB |
496 | put_pid(old_pid); |
497 | if (old_cred) | |
498 | put_cred(old_cred); | |
1da177e4 LT |
499 | out: |
500 | return err; | |
501 | } | |
502 | ||
503 | static int unix_release(struct socket *); | |
504 | static int unix_bind(struct socket *, struct sockaddr *, int); | |
505 | static int unix_stream_connect(struct socket *, struct sockaddr *, | |
506 | int addr_len, int flags); | |
507 | static int unix_socketpair(struct socket *, struct socket *); | |
508 | static int unix_accept(struct socket *, struct socket *, int); | |
509 | static int unix_getname(struct socket *, struct sockaddr *, int *, int); | |
510 | static unsigned int unix_poll(struct file *, struct socket *, poll_table *); | |
ec0d215f RW |
511 | static unsigned int unix_dgram_poll(struct file *, struct socket *, |
512 | poll_table *); | |
1da177e4 LT |
513 | static int unix_ioctl(struct socket *, unsigned int, unsigned long); |
514 | static int unix_shutdown(struct socket *, int); | |
515 | static int unix_stream_sendmsg(struct kiocb *, struct socket *, | |
516 | struct msghdr *, size_t); | |
517 | static int unix_stream_recvmsg(struct kiocb *, struct socket *, | |
518 | struct msghdr *, size_t, int); | |
519 | static int unix_dgram_sendmsg(struct kiocb *, struct socket *, | |
520 | struct msghdr *, size_t); | |
521 | static int unix_dgram_recvmsg(struct kiocb *, struct socket *, | |
522 | struct msghdr *, size_t, int); | |
523 | static int unix_dgram_connect(struct socket *, struct sockaddr *, | |
524 | int, int); | |
525 | static int unix_seqpacket_sendmsg(struct kiocb *, struct socket *, | |
526 | struct msghdr *, size_t); | |
527 | ||
90ddc4f0 | 528 | static const struct proto_ops unix_stream_ops = { |
1da177e4 LT |
529 | .family = PF_UNIX, |
530 | .owner = THIS_MODULE, | |
531 | .release = unix_release, | |
532 | .bind = unix_bind, | |
533 | .connect = unix_stream_connect, | |
534 | .socketpair = unix_socketpair, | |
535 | .accept = unix_accept, | |
536 | .getname = unix_getname, | |
537 | .poll = unix_poll, | |
538 | .ioctl = unix_ioctl, | |
539 | .listen = unix_listen, | |
540 | .shutdown = unix_shutdown, | |
541 | .setsockopt = sock_no_setsockopt, | |
542 | .getsockopt = sock_no_getsockopt, | |
543 | .sendmsg = unix_stream_sendmsg, | |
544 | .recvmsg = unix_stream_recvmsg, | |
545 | .mmap = sock_no_mmap, | |
546 | .sendpage = sock_no_sendpage, | |
547 | }; | |
548 | ||
90ddc4f0 | 549 | static const struct proto_ops unix_dgram_ops = { |
1da177e4 LT |
550 | .family = PF_UNIX, |
551 | .owner = THIS_MODULE, | |
552 | .release = unix_release, | |
553 | .bind = unix_bind, | |
554 | .connect = unix_dgram_connect, | |
555 | .socketpair = unix_socketpair, | |
556 | .accept = sock_no_accept, | |
557 | .getname = unix_getname, | |
ec0d215f | 558 | .poll = unix_dgram_poll, |
1da177e4 LT |
559 | .ioctl = unix_ioctl, |
560 | .listen = sock_no_listen, | |
561 | .shutdown = unix_shutdown, | |
562 | .setsockopt = sock_no_setsockopt, | |
563 | .getsockopt = sock_no_getsockopt, | |
564 | .sendmsg = unix_dgram_sendmsg, | |
565 | .recvmsg = unix_dgram_recvmsg, | |
566 | .mmap = sock_no_mmap, | |
567 | .sendpage = sock_no_sendpage, | |
568 | }; | |
569 | ||
90ddc4f0 | 570 | static const struct proto_ops unix_seqpacket_ops = { |
1da177e4 LT |
571 | .family = PF_UNIX, |
572 | .owner = THIS_MODULE, | |
573 | .release = unix_release, | |
574 | .bind = unix_bind, | |
575 | .connect = unix_stream_connect, | |
576 | .socketpair = unix_socketpair, | |
577 | .accept = unix_accept, | |
578 | .getname = unix_getname, | |
ec0d215f | 579 | .poll = unix_dgram_poll, |
1da177e4 LT |
580 | .ioctl = unix_ioctl, |
581 | .listen = unix_listen, | |
582 | .shutdown = unix_shutdown, | |
583 | .setsockopt = sock_no_setsockopt, | |
584 | .getsockopt = sock_no_getsockopt, | |
585 | .sendmsg = unix_seqpacket_sendmsg, | |
586 | .recvmsg = unix_dgram_recvmsg, | |
587 | .mmap = sock_no_mmap, | |
588 | .sendpage = sock_no_sendpage, | |
589 | }; | |
590 | ||
591 | static struct proto unix_proto = { | |
248969ae ED |
592 | .name = "UNIX", |
593 | .owner = THIS_MODULE, | |
248969ae | 594 | .obj_size = sizeof(struct unix_sock), |
1da177e4 LT |
595 | }; |
596 | ||
a09785a2 IM |
597 | /* |
598 | * AF_UNIX sockets do not interact with hardware, hence they | |
599 | * dont trigger interrupts - so it's safe for them to have | |
600 | * bh-unsafe locking for their sk_receive_queue.lock. Split off | |
601 | * this special lock-class by reinitializing the spinlock key: | |
602 | */ | |
603 | static struct lock_class_key af_unix_sk_receive_queue_lock_key; | |
604 | ||
6eba6a37 | 605 | static struct sock *unix_create1(struct net *net, struct socket *sock) |
1da177e4 LT |
606 | { |
607 | struct sock *sk = NULL; | |
608 | struct unix_sock *u; | |
609 | ||
518de9b3 ED |
610 | atomic_long_inc(&unix_nr_socks); |
611 | if (atomic_long_read(&unix_nr_socks) > 2 * get_max_files()) | |
1da177e4 LT |
612 | goto out; |
613 | ||
6257ff21 | 614 | sk = sk_alloc(net, PF_UNIX, GFP_KERNEL, &unix_proto); |
1da177e4 LT |
615 | if (!sk) |
616 | goto out; | |
617 | ||
6eba6a37 | 618 | sock_init_data(sock, sk); |
a09785a2 IM |
619 | lockdep_set_class(&sk->sk_receive_queue.lock, |
620 | &af_unix_sk_receive_queue_lock_key); | |
1da177e4 LT |
621 | |
622 | sk->sk_write_space = unix_write_space; | |
a0a53c8b | 623 | sk->sk_max_ack_backlog = net->unx.sysctl_max_dgram_qlen; |
1da177e4 LT |
624 | sk->sk_destruct = unix_sock_destructor; |
625 | u = unix_sk(sk); | |
626 | u->dentry = NULL; | |
627 | u->mnt = NULL; | |
fd19f329 | 628 | spin_lock_init(&u->lock); |
516e0cc5 | 629 | atomic_long_set(&u->inflight, 0); |
1fd05ba5 | 630 | INIT_LIST_HEAD(&u->link); |
57b47a53 | 631 | mutex_init(&u->readlock); /* single task reading lock */ |
1da177e4 LT |
632 | init_waitqueue_head(&u->peer_wait); |
633 | unix_insert_socket(unix_sockets_unbound, sk); | |
634 | out: | |
284b327b | 635 | if (sk == NULL) |
518de9b3 | 636 | atomic_long_dec(&unix_nr_socks); |
920de804 ED |
637 | else { |
638 | local_bh_disable(); | |
a8076d8d | 639 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); |
920de804 ED |
640 | local_bh_enable(); |
641 | } | |
1da177e4 LT |
642 | return sk; |
643 | } | |
644 | ||
3f378b68 EP |
645 | static int unix_create(struct net *net, struct socket *sock, int protocol, |
646 | int kern) | |
1da177e4 LT |
647 | { |
648 | if (protocol && protocol != PF_UNIX) | |
649 | return -EPROTONOSUPPORT; | |
650 | ||
651 | sock->state = SS_UNCONNECTED; | |
652 | ||
653 | switch (sock->type) { | |
654 | case SOCK_STREAM: | |
655 | sock->ops = &unix_stream_ops; | |
656 | break; | |
657 | /* | |
658 | * Believe it or not BSD has AF_UNIX, SOCK_RAW though | |
659 | * nothing uses it. | |
660 | */ | |
661 | case SOCK_RAW: | |
e27dfcea | 662 | sock->type = SOCK_DGRAM; |
1da177e4 LT |
663 | case SOCK_DGRAM: |
664 | sock->ops = &unix_dgram_ops; | |
665 | break; | |
666 | case SOCK_SEQPACKET: | |
667 | sock->ops = &unix_seqpacket_ops; | |
668 | break; | |
669 | default: | |
670 | return -ESOCKTNOSUPPORT; | |
671 | } | |
672 | ||
1b8d7ae4 | 673 | return unix_create1(net, sock) ? 0 : -ENOMEM; |
1da177e4 LT |
674 | } |
675 | ||
676 | static int unix_release(struct socket *sock) | |
677 | { | |
678 | struct sock *sk = sock->sk; | |
679 | ||
680 | if (!sk) | |
681 | return 0; | |
682 | ||
683 | sock->sk = NULL; | |
684 | ||
6eba6a37 | 685 | return unix_release_sock(sk, 0); |
1da177e4 LT |
686 | } |
687 | ||
688 | static int unix_autobind(struct socket *sock) | |
689 | { | |
690 | struct sock *sk = sock->sk; | |
3b1e0a65 | 691 | struct net *net = sock_net(sk); |
1da177e4 LT |
692 | struct unix_sock *u = unix_sk(sk); |
693 | static u32 ordernum = 1; | |
6eba6a37 | 694 | struct unix_address *addr; |
1da177e4 | 695 | int err; |
8df73ff9 | 696 | unsigned int retries = 0; |
1da177e4 | 697 | |
57b47a53 | 698 | mutex_lock(&u->readlock); |
1da177e4 LT |
699 | |
700 | err = 0; | |
701 | if (u->addr) | |
702 | goto out; | |
703 | ||
704 | err = -ENOMEM; | |
0da974f4 | 705 | addr = kzalloc(sizeof(*addr) + sizeof(short) + 16, GFP_KERNEL); |
1da177e4 LT |
706 | if (!addr) |
707 | goto out; | |
708 | ||
1da177e4 LT |
709 | addr->name->sun_family = AF_UNIX; |
710 | atomic_set(&addr->refcnt, 1); | |
711 | ||
712 | retry: | |
713 | addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + sizeof(short); | |
07f0757a | 714 | addr->hash = unix_hash_fold(csum_partial(addr->name, addr->len, 0)); |
1da177e4 | 715 | |
fbe9cc4a | 716 | spin_lock(&unix_table_lock); |
1da177e4 LT |
717 | ordernum = (ordernum+1)&0xFFFFF; |
718 | ||
097e66c5 | 719 | if (__unix_find_socket_byname(net, addr->name, addr->len, sock->type, |
1da177e4 | 720 | addr->hash)) { |
fbe9cc4a | 721 | spin_unlock(&unix_table_lock); |
8df73ff9 TH |
722 | /* |
723 | * __unix_find_socket_byname() may take long time if many names | |
724 | * are already in use. | |
725 | */ | |
726 | cond_resched(); | |
727 | /* Give up if all names seems to be in use. */ | |
728 | if (retries++ == 0xFFFFF) { | |
729 | err = -ENOSPC; | |
730 | kfree(addr); | |
731 | goto out; | |
732 | } | |
1da177e4 LT |
733 | goto retry; |
734 | } | |
735 | addr->hash ^= sk->sk_type; | |
736 | ||
737 | __unix_remove_socket(sk); | |
738 | u->addr = addr; | |
739 | __unix_insert_socket(&unix_socket_table[addr->hash], sk); | |
fbe9cc4a | 740 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
741 | err = 0; |
742 | ||
57b47a53 | 743 | out: mutex_unlock(&u->readlock); |
1da177e4 LT |
744 | return err; |
745 | } | |
746 | ||
097e66c5 DL |
747 | static struct sock *unix_find_other(struct net *net, |
748 | struct sockaddr_un *sunname, int len, | |
1da177e4 LT |
749 | int type, unsigned hash, int *error) |
750 | { | |
751 | struct sock *u; | |
421748ec | 752 | struct path path; |
1da177e4 | 753 | int err = 0; |
ac7bfa62 | 754 | |
1da177e4 | 755 | if (sunname->sun_path[0]) { |
421748ec AV |
756 | struct inode *inode; |
757 | err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, &path); | |
1da177e4 LT |
758 | if (err) |
759 | goto fail; | |
421748ec AV |
760 | inode = path.dentry->d_inode; |
761 | err = inode_permission(inode, MAY_WRITE); | |
1da177e4 LT |
762 | if (err) |
763 | goto put_fail; | |
764 | ||
765 | err = -ECONNREFUSED; | |
421748ec | 766 | if (!S_ISSOCK(inode->i_mode)) |
1da177e4 | 767 | goto put_fail; |
6616f788 | 768 | u = unix_find_socket_byinode(inode); |
1da177e4 LT |
769 | if (!u) |
770 | goto put_fail; | |
771 | ||
772 | if (u->sk_type == type) | |
421748ec | 773 | touch_atime(path.mnt, path.dentry); |
1da177e4 | 774 | |
421748ec | 775 | path_put(&path); |
1da177e4 | 776 | |
e27dfcea | 777 | err = -EPROTOTYPE; |
1da177e4 LT |
778 | if (u->sk_type != type) { |
779 | sock_put(u); | |
780 | goto fail; | |
781 | } | |
782 | } else { | |
783 | err = -ECONNREFUSED; | |
e27dfcea | 784 | u = unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
785 | if (u) { |
786 | struct dentry *dentry; | |
787 | dentry = unix_sk(u)->dentry; | |
788 | if (dentry) | |
789 | touch_atime(unix_sk(u)->mnt, dentry); | |
790 | } else | |
791 | goto fail; | |
792 | } | |
793 | return u; | |
794 | ||
795 | put_fail: | |
421748ec | 796 | path_put(&path); |
1da177e4 | 797 | fail: |
e27dfcea | 798 | *error = err; |
1da177e4 LT |
799 | return NULL; |
800 | } | |
801 | ||
802 | ||
803 | static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) | |
804 | { | |
805 | struct sock *sk = sock->sk; | |
3b1e0a65 | 806 | struct net *net = sock_net(sk); |
1da177e4 | 807 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 808 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
6eba6a37 | 809 | struct dentry *dentry = NULL; |
1da177e4 LT |
810 | struct nameidata nd; |
811 | int err; | |
812 | unsigned hash; | |
813 | struct unix_address *addr; | |
814 | struct hlist_head *list; | |
815 | ||
816 | err = -EINVAL; | |
817 | if (sunaddr->sun_family != AF_UNIX) | |
818 | goto out; | |
819 | ||
e27dfcea | 820 | if (addr_len == sizeof(short)) { |
1da177e4 LT |
821 | err = unix_autobind(sock); |
822 | goto out; | |
823 | } | |
824 | ||
825 | err = unix_mkname(sunaddr, addr_len, &hash); | |
826 | if (err < 0) | |
827 | goto out; | |
828 | addr_len = err; | |
829 | ||
57b47a53 | 830 | mutex_lock(&u->readlock); |
1da177e4 LT |
831 | |
832 | err = -EINVAL; | |
833 | if (u->addr) | |
834 | goto out_up; | |
835 | ||
836 | err = -ENOMEM; | |
837 | addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL); | |
838 | if (!addr) | |
839 | goto out_up; | |
840 | ||
841 | memcpy(addr->name, sunaddr, addr_len); | |
842 | addr->len = addr_len; | |
843 | addr->hash = hash ^ sk->sk_type; | |
844 | atomic_set(&addr->refcnt, 1); | |
845 | ||
846 | if (sunaddr->sun_path[0]) { | |
847 | unsigned int mode; | |
848 | err = 0; | |
849 | /* | |
850 | * Get the parent directory, calculate the hash for last | |
851 | * component. | |
852 | */ | |
853 | err = path_lookup(sunaddr->sun_path, LOOKUP_PARENT, &nd); | |
854 | if (err) | |
855 | goto out_mknod_parent; | |
f81a0bff CH |
856 | |
857 | dentry = lookup_create(&nd, 0); | |
1da177e4 LT |
858 | err = PTR_ERR(dentry); |
859 | if (IS_ERR(dentry)) | |
860 | goto out_mknod_unlock; | |
f81a0bff | 861 | |
1da177e4 LT |
862 | /* |
863 | * All right, let's create it. | |
864 | */ | |
865 | mode = S_IFSOCK | | |
ce3b0f8d | 866 | (SOCK_INODE(sock)->i_mode & ~current_umask()); |
463c3197 DH |
867 | err = mnt_want_write(nd.path.mnt); |
868 | if (err) | |
869 | goto out_mknod_dput; | |
be6d3e56 KT |
870 | err = security_path_mknod(&nd.path, dentry, mode, 0); |
871 | if (err) | |
872 | goto out_mknod_drop_write; | |
4ac91378 | 873 | err = vfs_mknod(nd.path.dentry->d_inode, dentry, mode, 0); |
be6d3e56 | 874 | out_mknod_drop_write: |
463c3197 | 875 | mnt_drop_write(nd.path.mnt); |
1da177e4 LT |
876 | if (err) |
877 | goto out_mknod_dput; | |
4ac91378 JB |
878 | mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
879 | dput(nd.path.dentry); | |
880 | nd.path.dentry = dentry; | |
1da177e4 LT |
881 | |
882 | addr->hash = UNIX_HASH_SIZE; | |
883 | } | |
884 | ||
fbe9cc4a | 885 | spin_lock(&unix_table_lock); |
1da177e4 LT |
886 | |
887 | if (!sunaddr->sun_path[0]) { | |
888 | err = -EADDRINUSE; | |
097e66c5 | 889 | if (__unix_find_socket_byname(net, sunaddr, addr_len, |
1da177e4 LT |
890 | sk->sk_type, hash)) { |
891 | unix_release_addr(addr); | |
892 | goto out_unlock; | |
893 | } | |
894 | ||
895 | list = &unix_socket_table[addr->hash]; | |
896 | } else { | |
897 | list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)]; | |
4ac91378 JB |
898 | u->dentry = nd.path.dentry; |
899 | u->mnt = nd.path.mnt; | |
1da177e4 LT |
900 | } |
901 | ||
902 | err = 0; | |
903 | __unix_remove_socket(sk); | |
904 | u->addr = addr; | |
905 | __unix_insert_socket(list, sk); | |
906 | ||
907 | out_unlock: | |
fbe9cc4a | 908 | spin_unlock(&unix_table_lock); |
1da177e4 | 909 | out_up: |
57b47a53 | 910 | mutex_unlock(&u->readlock); |
1da177e4 LT |
911 | out: |
912 | return err; | |
913 | ||
914 | out_mknod_dput: | |
915 | dput(dentry); | |
916 | out_mknod_unlock: | |
4ac91378 | 917 | mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
1d957f9b | 918 | path_put(&nd.path); |
1da177e4 | 919 | out_mknod_parent: |
e27dfcea JK |
920 | if (err == -EEXIST) |
921 | err = -EADDRINUSE; | |
1da177e4 LT |
922 | unix_release_addr(addr); |
923 | goto out_up; | |
924 | } | |
925 | ||
278a3de5 DM |
926 | static void unix_state_double_lock(struct sock *sk1, struct sock *sk2) |
927 | { | |
928 | if (unlikely(sk1 == sk2) || !sk2) { | |
929 | unix_state_lock(sk1); | |
930 | return; | |
931 | } | |
932 | if (sk1 < sk2) { | |
933 | unix_state_lock(sk1); | |
934 | unix_state_lock_nested(sk2); | |
935 | } else { | |
936 | unix_state_lock(sk2); | |
937 | unix_state_lock_nested(sk1); | |
938 | } | |
939 | } | |
940 | ||
941 | static void unix_state_double_unlock(struct sock *sk1, struct sock *sk2) | |
942 | { | |
943 | if (unlikely(sk1 == sk2) || !sk2) { | |
944 | unix_state_unlock(sk1); | |
945 | return; | |
946 | } | |
947 | unix_state_unlock(sk1); | |
948 | unix_state_unlock(sk2); | |
949 | } | |
950 | ||
1da177e4 LT |
951 | static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr, |
952 | int alen, int flags) | |
953 | { | |
954 | struct sock *sk = sock->sk; | |
3b1e0a65 | 955 | struct net *net = sock_net(sk); |
e27dfcea | 956 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)addr; |
1da177e4 LT |
957 | struct sock *other; |
958 | unsigned hash; | |
959 | int err; | |
960 | ||
961 | if (addr->sa_family != AF_UNSPEC) { | |
962 | err = unix_mkname(sunaddr, alen, &hash); | |
963 | if (err < 0) | |
964 | goto out; | |
965 | alen = err; | |
966 | ||
967 | if (test_bit(SOCK_PASSCRED, &sock->flags) && | |
968 | !unix_sk(sk)->addr && (err = unix_autobind(sock)) != 0) | |
969 | goto out; | |
970 | ||
278a3de5 | 971 | restart: |
e27dfcea | 972 | other = unix_find_other(net, sunaddr, alen, sock->type, hash, &err); |
1da177e4 LT |
973 | if (!other) |
974 | goto out; | |
975 | ||
278a3de5 DM |
976 | unix_state_double_lock(sk, other); |
977 | ||
978 | /* Apparently VFS overslept socket death. Retry. */ | |
979 | if (sock_flag(other, SOCK_DEAD)) { | |
980 | unix_state_double_unlock(sk, other); | |
981 | sock_put(other); | |
982 | goto restart; | |
983 | } | |
1da177e4 LT |
984 | |
985 | err = -EPERM; | |
986 | if (!unix_may_send(sk, other)) | |
987 | goto out_unlock; | |
988 | ||
989 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
990 | if (err) | |
991 | goto out_unlock; | |
992 | ||
993 | } else { | |
994 | /* | |
995 | * 1003.1g breaking connected state with AF_UNSPEC | |
996 | */ | |
997 | other = NULL; | |
278a3de5 | 998 | unix_state_double_lock(sk, other); |
1da177e4 LT |
999 | } |
1000 | ||
1001 | /* | |
1002 | * If it was connected, reconnect. | |
1003 | */ | |
1004 | if (unix_peer(sk)) { | |
1005 | struct sock *old_peer = unix_peer(sk); | |
e27dfcea | 1006 | unix_peer(sk) = other; |
278a3de5 | 1007 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1008 | |
1009 | if (other != old_peer) | |
1010 | unix_dgram_disconnected(sk, old_peer); | |
1011 | sock_put(old_peer); | |
1012 | } else { | |
e27dfcea | 1013 | unix_peer(sk) = other; |
278a3de5 | 1014 | unix_state_double_unlock(sk, other); |
1da177e4 | 1015 | } |
ac7bfa62 | 1016 | return 0; |
1da177e4 LT |
1017 | |
1018 | out_unlock: | |
278a3de5 | 1019 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1020 | sock_put(other); |
1021 | out: | |
1022 | return err; | |
1023 | } | |
1024 | ||
1025 | static long unix_wait_for_peer(struct sock *other, long timeo) | |
1026 | { | |
1027 | struct unix_sock *u = unix_sk(other); | |
1028 | int sched; | |
1029 | DEFINE_WAIT(wait); | |
1030 | ||
1031 | prepare_to_wait_exclusive(&u->peer_wait, &wait, TASK_INTERRUPTIBLE); | |
1032 | ||
1033 | sched = !sock_flag(other, SOCK_DEAD) && | |
1034 | !(other->sk_shutdown & RCV_SHUTDOWN) && | |
3c73419c | 1035 | unix_recvq_full(other); |
1da177e4 | 1036 | |
1c92b4e5 | 1037 | unix_state_unlock(other); |
1da177e4 LT |
1038 | |
1039 | if (sched) | |
1040 | timeo = schedule_timeout(timeo); | |
1041 | ||
1042 | finish_wait(&u->peer_wait, &wait); | |
1043 | return timeo; | |
1044 | } | |
1045 | ||
1046 | static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr, | |
1047 | int addr_len, int flags) | |
1048 | { | |
e27dfcea | 1049 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
1da177e4 | 1050 | struct sock *sk = sock->sk; |
3b1e0a65 | 1051 | struct net *net = sock_net(sk); |
1da177e4 LT |
1052 | struct unix_sock *u = unix_sk(sk), *newu, *otheru; |
1053 | struct sock *newsk = NULL; | |
1054 | struct sock *other = NULL; | |
1055 | struct sk_buff *skb = NULL; | |
1056 | unsigned hash; | |
1057 | int st; | |
1058 | int err; | |
1059 | long timeo; | |
1060 | ||
1061 | err = unix_mkname(sunaddr, addr_len, &hash); | |
1062 | if (err < 0) | |
1063 | goto out; | |
1064 | addr_len = err; | |
1065 | ||
f64f9e71 JP |
1066 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr && |
1067 | (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1068 | goto out; |
1069 | ||
1070 | timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); | |
1071 | ||
1072 | /* First of all allocate resources. | |
1073 | If we will make it after state is locked, | |
1074 | we will have to recheck all again in any case. | |
1075 | */ | |
1076 | ||
1077 | err = -ENOMEM; | |
1078 | ||
1079 | /* create new sock for complete connection */ | |
3b1e0a65 | 1080 | newsk = unix_create1(sock_net(sk), NULL); |
1da177e4 LT |
1081 | if (newsk == NULL) |
1082 | goto out; | |
1083 | ||
1084 | /* Allocate skb for sending to listening sock */ | |
1085 | skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL); | |
1086 | if (skb == NULL) | |
1087 | goto out; | |
1088 | ||
1089 | restart: | |
1090 | /* Find listening sock. */ | |
097e66c5 | 1091 | other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, &err); |
1da177e4 LT |
1092 | if (!other) |
1093 | goto out; | |
1094 | ||
1095 | /* Latch state of peer */ | |
1c92b4e5 | 1096 | unix_state_lock(other); |
1da177e4 LT |
1097 | |
1098 | /* Apparently VFS overslept socket death. Retry. */ | |
1099 | if (sock_flag(other, SOCK_DEAD)) { | |
1c92b4e5 | 1100 | unix_state_unlock(other); |
1da177e4 LT |
1101 | sock_put(other); |
1102 | goto restart; | |
1103 | } | |
1104 | ||
1105 | err = -ECONNREFUSED; | |
1106 | if (other->sk_state != TCP_LISTEN) | |
1107 | goto out_unlock; | |
77238f2b TS |
1108 | if (other->sk_shutdown & RCV_SHUTDOWN) |
1109 | goto out_unlock; | |
1da177e4 | 1110 | |
3c73419c | 1111 | if (unix_recvq_full(other)) { |
1da177e4 LT |
1112 | err = -EAGAIN; |
1113 | if (!timeo) | |
1114 | goto out_unlock; | |
1115 | ||
1116 | timeo = unix_wait_for_peer(other, timeo); | |
1117 | ||
1118 | err = sock_intr_errno(timeo); | |
1119 | if (signal_pending(current)) | |
1120 | goto out; | |
1121 | sock_put(other); | |
1122 | goto restart; | |
ac7bfa62 | 1123 | } |
1da177e4 LT |
1124 | |
1125 | /* Latch our state. | |
1126 | ||
1127 | It is tricky place. We need to grab write lock and cannot | |
1128 | drop lock on peer. It is dangerous because deadlock is | |
1129 | possible. Connect to self case and simultaneous | |
1130 | attempt to connect are eliminated by checking socket | |
1131 | state. other is TCP_LISTEN, if sk is TCP_LISTEN we | |
1132 | check this before attempt to grab lock. | |
1133 | ||
1134 | Well, and we have to recheck the state after socket locked. | |
1135 | */ | |
1136 | st = sk->sk_state; | |
1137 | ||
1138 | switch (st) { | |
1139 | case TCP_CLOSE: | |
1140 | /* This is ok... continue with connect */ | |
1141 | break; | |
1142 | case TCP_ESTABLISHED: | |
1143 | /* Socket is already connected */ | |
1144 | err = -EISCONN; | |
1145 | goto out_unlock; | |
1146 | default: | |
1147 | err = -EINVAL; | |
1148 | goto out_unlock; | |
1149 | } | |
1150 | ||
1c92b4e5 | 1151 | unix_state_lock_nested(sk); |
1da177e4 LT |
1152 | |
1153 | if (sk->sk_state != st) { | |
1c92b4e5 DM |
1154 | unix_state_unlock(sk); |
1155 | unix_state_unlock(other); | |
1da177e4 LT |
1156 | sock_put(other); |
1157 | goto restart; | |
1158 | } | |
1159 | ||
1160 | err = security_unix_stream_connect(sock, other->sk_socket, newsk); | |
1161 | if (err) { | |
1c92b4e5 | 1162 | unix_state_unlock(sk); |
1da177e4 LT |
1163 | goto out_unlock; |
1164 | } | |
1165 | ||
1166 | /* The way is open! Fastly set all the necessary fields... */ | |
1167 | ||
1168 | sock_hold(sk); | |
1169 | unix_peer(newsk) = sk; | |
1170 | newsk->sk_state = TCP_ESTABLISHED; | |
1171 | newsk->sk_type = sk->sk_type; | |
109f6e39 | 1172 | init_peercred(newsk); |
1da177e4 | 1173 | newu = unix_sk(newsk); |
43815482 | 1174 | newsk->sk_wq = &newu->peer_wq; |
1da177e4 LT |
1175 | otheru = unix_sk(other); |
1176 | ||
1177 | /* copy address information from listening to new sock*/ | |
1178 | if (otheru->addr) { | |
1179 | atomic_inc(&otheru->addr->refcnt); | |
1180 | newu->addr = otheru->addr; | |
1181 | } | |
1182 | if (otheru->dentry) { | |
1183 | newu->dentry = dget(otheru->dentry); | |
1184 | newu->mnt = mntget(otheru->mnt); | |
1185 | } | |
1186 | ||
1187 | /* Set credentials */ | |
109f6e39 | 1188 | copy_peercred(sk, other); |
1da177e4 | 1189 | |
1da177e4 LT |
1190 | sock->state = SS_CONNECTED; |
1191 | sk->sk_state = TCP_ESTABLISHED; | |
830a1e5c BL |
1192 | sock_hold(newsk); |
1193 | ||
1194 | smp_mb__after_atomic_inc(); /* sock_hold() does an atomic_inc() */ | |
1195 | unix_peer(sk) = newsk; | |
1da177e4 | 1196 | |
1c92b4e5 | 1197 | unix_state_unlock(sk); |
1da177e4 LT |
1198 | |
1199 | /* take ten and and send info to listening sock */ | |
1200 | spin_lock(&other->sk_receive_queue.lock); | |
1201 | __skb_queue_tail(&other->sk_receive_queue, skb); | |
1da177e4 | 1202 | spin_unlock(&other->sk_receive_queue.lock); |
1c92b4e5 | 1203 | unix_state_unlock(other); |
1da177e4 LT |
1204 | other->sk_data_ready(other, 0); |
1205 | sock_put(other); | |
1206 | return 0; | |
1207 | ||
1208 | out_unlock: | |
1209 | if (other) | |
1c92b4e5 | 1210 | unix_state_unlock(other); |
1da177e4 LT |
1211 | |
1212 | out: | |
40d44446 | 1213 | kfree_skb(skb); |
1da177e4 LT |
1214 | if (newsk) |
1215 | unix_release_sock(newsk, 0); | |
1216 | if (other) | |
1217 | sock_put(other); | |
1218 | return err; | |
1219 | } | |
1220 | ||
1221 | static int unix_socketpair(struct socket *socka, struct socket *sockb) | |
1222 | { | |
e27dfcea | 1223 | struct sock *ska = socka->sk, *skb = sockb->sk; |
1da177e4 LT |
1224 | |
1225 | /* Join our sockets back to back */ | |
1226 | sock_hold(ska); | |
1227 | sock_hold(skb); | |
e27dfcea JK |
1228 | unix_peer(ska) = skb; |
1229 | unix_peer(skb) = ska; | |
109f6e39 EB |
1230 | init_peercred(ska); |
1231 | init_peercred(skb); | |
1da177e4 LT |
1232 | |
1233 | if (ska->sk_type != SOCK_DGRAM) { | |
1234 | ska->sk_state = TCP_ESTABLISHED; | |
1235 | skb->sk_state = TCP_ESTABLISHED; | |
1236 | socka->state = SS_CONNECTED; | |
1237 | sockb->state = SS_CONNECTED; | |
1238 | } | |
1239 | return 0; | |
1240 | } | |
1241 | ||
1242 | static int unix_accept(struct socket *sock, struct socket *newsock, int flags) | |
1243 | { | |
1244 | struct sock *sk = sock->sk; | |
1245 | struct sock *tsk; | |
1246 | struct sk_buff *skb; | |
1247 | int err; | |
1248 | ||
1249 | err = -EOPNOTSUPP; | |
6eba6a37 | 1250 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
1da177e4 LT |
1251 | goto out; |
1252 | ||
1253 | err = -EINVAL; | |
1254 | if (sk->sk_state != TCP_LISTEN) | |
1255 | goto out; | |
1256 | ||
1257 | /* If socket state is TCP_LISTEN it cannot change (for now...), | |
1258 | * so that no locks are necessary. | |
1259 | */ | |
1260 | ||
1261 | skb = skb_recv_datagram(sk, 0, flags&O_NONBLOCK, &err); | |
1262 | if (!skb) { | |
1263 | /* This means receive shutdown. */ | |
1264 | if (err == 0) | |
1265 | err = -EINVAL; | |
1266 | goto out; | |
1267 | } | |
1268 | ||
1269 | tsk = skb->sk; | |
1270 | skb_free_datagram(sk, skb); | |
1271 | wake_up_interruptible(&unix_sk(sk)->peer_wait); | |
1272 | ||
1273 | /* attach accepted sock to socket */ | |
1c92b4e5 | 1274 | unix_state_lock(tsk); |
1da177e4 LT |
1275 | newsock->state = SS_CONNECTED; |
1276 | sock_graft(tsk, newsock); | |
1c92b4e5 | 1277 | unix_state_unlock(tsk); |
1da177e4 LT |
1278 | return 0; |
1279 | ||
1280 | out: | |
1281 | return err; | |
1282 | } | |
1283 | ||
1284 | ||
1285 | static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer) | |
1286 | { | |
1287 | struct sock *sk = sock->sk; | |
1288 | struct unix_sock *u; | |
13cfa97b | 1289 | DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr, uaddr); |
1da177e4 LT |
1290 | int err = 0; |
1291 | ||
1292 | if (peer) { | |
1293 | sk = unix_peer_get(sk); | |
1294 | ||
1295 | err = -ENOTCONN; | |
1296 | if (!sk) | |
1297 | goto out; | |
1298 | err = 0; | |
1299 | } else { | |
1300 | sock_hold(sk); | |
1301 | } | |
1302 | ||
1303 | u = unix_sk(sk); | |
1c92b4e5 | 1304 | unix_state_lock(sk); |
1da177e4 LT |
1305 | if (!u->addr) { |
1306 | sunaddr->sun_family = AF_UNIX; | |
1307 | sunaddr->sun_path[0] = 0; | |
1308 | *uaddr_len = sizeof(short); | |
1309 | } else { | |
1310 | struct unix_address *addr = u->addr; | |
1311 | ||
1312 | *uaddr_len = addr->len; | |
1313 | memcpy(sunaddr, addr->name, *uaddr_len); | |
1314 | } | |
1c92b4e5 | 1315 | unix_state_unlock(sk); |
1da177e4 LT |
1316 | sock_put(sk); |
1317 | out: | |
1318 | return err; | |
1319 | } | |
1320 | ||
1321 | static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb) | |
1322 | { | |
1323 | int i; | |
1324 | ||
1325 | scm->fp = UNIXCB(skb).fp; | |
1da177e4 LT |
1326 | UNIXCB(skb).fp = NULL; |
1327 | ||
6eba6a37 | 1328 | for (i = scm->fp->count-1; i >= 0; i--) |
1da177e4 LT |
1329 | unix_notinflight(scm->fp->fp[i]); |
1330 | } | |
1331 | ||
7361c36c | 1332 | static void unix_destruct_scm(struct sk_buff *skb) |
1da177e4 LT |
1333 | { |
1334 | struct scm_cookie scm; | |
1335 | memset(&scm, 0, sizeof(scm)); | |
7361c36c EB |
1336 | scm.pid = UNIXCB(skb).pid; |
1337 | scm.cred = UNIXCB(skb).cred; | |
1338 | if (UNIXCB(skb).fp) | |
1339 | unix_detach_fds(&scm, skb); | |
1da177e4 LT |
1340 | |
1341 | /* Alas, it calls VFS */ | |
1342 | /* So fscking what? fput() had been SMP-safe since the last Summer */ | |
1343 | scm_destroy(&scm); | |
1344 | sock_wfree(skb); | |
1345 | } | |
1346 | ||
25888e30 ED |
1347 | #define MAX_RECURSION_LEVEL 4 |
1348 | ||
6209344f | 1349 | static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb) |
1da177e4 LT |
1350 | { |
1351 | int i; | |
25888e30 ED |
1352 | unsigned char max_level = 0; |
1353 | int unix_sock_count = 0; | |
1354 | ||
1355 | for (i = scm->fp->count - 1; i >= 0; i--) { | |
1356 | struct sock *sk = unix_get_socket(scm->fp->fp[i]); | |
1357 | ||
1358 | if (sk) { | |
1359 | unix_sock_count++; | |
1360 | max_level = max(max_level, | |
1361 | unix_sk(sk)->recursion_level); | |
1362 | } | |
1363 | } | |
1364 | if (unlikely(max_level > MAX_RECURSION_LEVEL)) | |
1365 | return -ETOOMANYREFS; | |
6209344f MS |
1366 | |
1367 | /* | |
1368 | * Need to duplicate file references for the sake of garbage | |
1369 | * collection. Otherwise a socket in the fps might become a | |
1370 | * candidate for GC while the skb is not yet queued. | |
1371 | */ | |
1372 | UNIXCB(skb).fp = scm_fp_dup(scm->fp); | |
1373 | if (!UNIXCB(skb).fp) | |
1374 | return -ENOMEM; | |
1375 | ||
25888e30 ED |
1376 | if (unix_sock_count) { |
1377 | for (i = scm->fp->count - 1; i >= 0; i--) | |
1378 | unix_inflight(scm->fp->fp[i]); | |
1379 | } | |
1380 | return max_level; | |
1da177e4 LT |
1381 | } |
1382 | ||
7361c36c EB |
1383 | static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool send_fds) |
1384 | { | |
1385 | int err = 0; | |
1386 | UNIXCB(skb).pid = get_pid(scm->pid); | |
1387 | UNIXCB(skb).cred = get_cred(scm->cred); | |
1388 | UNIXCB(skb).fp = NULL; | |
1389 | if (scm->fp && send_fds) | |
1390 | err = unix_attach_fds(scm, skb); | |
1391 | ||
1392 | skb->destructor = unix_destruct_scm; | |
1393 | return err; | |
1394 | } | |
1395 | ||
1da177e4 LT |
1396 | /* |
1397 | * Send AF_UNIX data. | |
1398 | */ | |
1399 | ||
1400 | static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1401 | struct msghdr *msg, size_t len) | |
1402 | { | |
1403 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1404 | struct sock *sk = sock->sk; | |
3b1e0a65 | 1405 | struct net *net = sock_net(sk); |
1da177e4 | 1406 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 1407 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1408 | struct sock *other = NULL; |
1409 | int namelen = 0; /* fake GCC */ | |
1410 | int err; | |
1411 | unsigned hash; | |
1412 | struct sk_buff *skb; | |
1413 | long timeo; | |
1414 | struct scm_cookie tmp_scm; | |
25888e30 | 1415 | int max_level; |
1da177e4 LT |
1416 | |
1417 | if (NULL == siocb->scm) | |
1418 | siocb->scm = &tmp_scm; | |
5f23b734 | 1419 | wait_for_unix_gc(); |
1da177e4 LT |
1420 | err = scm_send(sock, msg, siocb->scm); |
1421 | if (err < 0) | |
1422 | return err; | |
1423 | ||
1424 | err = -EOPNOTSUPP; | |
1425 | if (msg->msg_flags&MSG_OOB) | |
1426 | goto out; | |
1427 | ||
1428 | if (msg->msg_namelen) { | |
1429 | err = unix_mkname(sunaddr, msg->msg_namelen, &hash); | |
1430 | if (err < 0) | |
1431 | goto out; | |
1432 | namelen = err; | |
1433 | } else { | |
1434 | sunaddr = NULL; | |
1435 | err = -ENOTCONN; | |
1436 | other = unix_peer_get(sk); | |
1437 | if (!other) | |
1438 | goto out; | |
1439 | } | |
1440 | ||
f64f9e71 JP |
1441 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr |
1442 | && (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1443 | goto out; |
1444 | ||
1445 | err = -EMSGSIZE; | |
1446 | if (len > sk->sk_sndbuf - 32) | |
1447 | goto out; | |
1448 | ||
1449 | skb = sock_alloc_send_skb(sk, len, msg->msg_flags&MSG_DONTWAIT, &err); | |
e27dfcea | 1450 | if (skb == NULL) |
1da177e4 LT |
1451 | goto out; |
1452 | ||
7361c36c | 1453 | err = unix_scm_to_skb(siocb->scm, skb, true); |
25888e30 | 1454 | if (err < 0) |
7361c36c | 1455 | goto out_free; |
25888e30 | 1456 | max_level = err + 1; |
dc49c1f9 | 1457 | unix_get_secdata(siocb->scm, skb); |
877ce7c1 | 1458 | |
badff6d0 | 1459 | skb_reset_transport_header(skb); |
6eba6a37 | 1460 | err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); |
1da177e4 LT |
1461 | if (err) |
1462 | goto out_free; | |
1463 | ||
1464 | timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); | |
1465 | ||
1466 | restart: | |
1467 | if (!other) { | |
1468 | err = -ECONNRESET; | |
1469 | if (sunaddr == NULL) | |
1470 | goto out_free; | |
1471 | ||
097e66c5 | 1472 | other = unix_find_other(net, sunaddr, namelen, sk->sk_type, |
1da177e4 | 1473 | hash, &err); |
e27dfcea | 1474 | if (other == NULL) |
1da177e4 LT |
1475 | goto out_free; |
1476 | } | |
1477 | ||
1c92b4e5 | 1478 | unix_state_lock(other); |
1da177e4 LT |
1479 | err = -EPERM; |
1480 | if (!unix_may_send(sk, other)) | |
1481 | goto out_unlock; | |
1482 | ||
1483 | if (sock_flag(other, SOCK_DEAD)) { | |
1484 | /* | |
1485 | * Check with 1003.1g - what should | |
1486 | * datagram error | |
1487 | */ | |
1c92b4e5 | 1488 | unix_state_unlock(other); |
1da177e4 LT |
1489 | sock_put(other); |
1490 | ||
1491 | err = 0; | |
1c92b4e5 | 1492 | unix_state_lock(sk); |
1da177e4 | 1493 | if (unix_peer(sk) == other) { |
e27dfcea | 1494 | unix_peer(sk) = NULL; |
1c92b4e5 | 1495 | unix_state_unlock(sk); |
1da177e4 LT |
1496 | |
1497 | unix_dgram_disconnected(sk, other); | |
1498 | sock_put(other); | |
1499 | err = -ECONNREFUSED; | |
1500 | } else { | |
1c92b4e5 | 1501 | unix_state_unlock(sk); |
1da177e4 LT |
1502 | } |
1503 | ||
1504 | other = NULL; | |
1505 | if (err) | |
1506 | goto out_free; | |
1507 | goto restart; | |
1508 | } | |
1509 | ||
1510 | err = -EPIPE; | |
1511 | if (other->sk_shutdown & RCV_SHUTDOWN) | |
1512 | goto out_unlock; | |
1513 | ||
1514 | if (sk->sk_type != SOCK_SEQPACKET) { | |
1515 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
1516 | if (err) | |
1517 | goto out_unlock; | |
1518 | } | |
1519 | ||
3c73419c | 1520 | if (unix_peer(other) != sk && unix_recvq_full(other)) { |
1da177e4 LT |
1521 | if (!timeo) { |
1522 | err = -EAGAIN; | |
1523 | goto out_unlock; | |
1524 | } | |
1525 | ||
1526 | timeo = unix_wait_for_peer(other, timeo); | |
1527 | ||
1528 | err = sock_intr_errno(timeo); | |
1529 | if (signal_pending(current)) | |
1530 | goto out_free; | |
1531 | ||
1532 | goto restart; | |
1533 | } | |
1534 | ||
3f66116e AC |
1535 | if (sock_flag(other, SOCK_RCVTSTAMP)) |
1536 | __net_timestamp(skb); | |
1da177e4 | 1537 | skb_queue_tail(&other->sk_receive_queue, skb); |
25888e30 ED |
1538 | if (max_level > unix_sk(other)->recursion_level) |
1539 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1540 | unix_state_unlock(other); |
1da177e4 LT |
1541 | other->sk_data_ready(other, len); |
1542 | sock_put(other); | |
1543 | scm_destroy(siocb->scm); | |
1544 | return len; | |
1545 | ||
1546 | out_unlock: | |
1c92b4e5 | 1547 | unix_state_unlock(other); |
1da177e4 LT |
1548 | out_free: |
1549 | kfree_skb(skb); | |
1550 | out: | |
1551 | if (other) | |
1552 | sock_put(other); | |
1553 | scm_destroy(siocb->scm); | |
1554 | return err; | |
1555 | } | |
1556 | ||
ac7bfa62 | 1557 | |
1da177e4 LT |
1558 | static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, |
1559 | struct msghdr *msg, size_t len) | |
1560 | { | |
1561 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1562 | struct sock *sk = sock->sk; | |
1563 | struct sock *other = NULL; | |
e27dfcea | 1564 | struct sockaddr_un *sunaddr = msg->msg_name; |
6eba6a37 | 1565 | int err, size; |
1da177e4 | 1566 | struct sk_buff *skb; |
e27dfcea | 1567 | int sent = 0; |
1da177e4 | 1568 | struct scm_cookie tmp_scm; |
8ba69ba6 | 1569 | bool fds_sent = false; |
25888e30 | 1570 | int max_level; |
1da177e4 LT |
1571 | |
1572 | if (NULL == siocb->scm) | |
1573 | siocb->scm = &tmp_scm; | |
5f23b734 | 1574 | wait_for_unix_gc(); |
1da177e4 LT |
1575 | err = scm_send(sock, msg, siocb->scm); |
1576 | if (err < 0) | |
1577 | return err; | |
1578 | ||
1579 | err = -EOPNOTSUPP; | |
1580 | if (msg->msg_flags&MSG_OOB) | |
1581 | goto out_err; | |
1582 | ||
1583 | if (msg->msg_namelen) { | |
1584 | err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; | |
1585 | goto out_err; | |
1586 | } else { | |
1587 | sunaddr = NULL; | |
1588 | err = -ENOTCONN; | |
830a1e5c | 1589 | other = unix_peer(sk); |
1da177e4 LT |
1590 | if (!other) |
1591 | goto out_err; | |
1592 | } | |
1593 | ||
1594 | if (sk->sk_shutdown & SEND_SHUTDOWN) | |
1595 | goto pipe_err; | |
1596 | ||
6eba6a37 | 1597 | while (sent < len) { |
1da177e4 | 1598 | /* |
e9df7d7f BL |
1599 | * Optimisation for the fact that under 0.01% of X |
1600 | * messages typically need breaking up. | |
1da177e4 LT |
1601 | */ |
1602 | ||
e9df7d7f | 1603 | size = len-sent; |
1da177e4 LT |
1604 | |
1605 | /* Keep two messages in the pipe so it schedules better */ | |
e9df7d7f BL |
1606 | if (size > ((sk->sk_sndbuf >> 1) - 64)) |
1607 | size = (sk->sk_sndbuf >> 1) - 64; | |
1da177e4 LT |
1608 | |
1609 | if (size > SKB_MAX_ALLOC) | |
1610 | size = SKB_MAX_ALLOC; | |
ac7bfa62 | 1611 | |
1da177e4 LT |
1612 | /* |
1613 | * Grab a buffer | |
1614 | */ | |
ac7bfa62 | 1615 | |
6eba6a37 ED |
1616 | skb = sock_alloc_send_skb(sk, size, msg->msg_flags&MSG_DONTWAIT, |
1617 | &err); | |
1da177e4 | 1618 | |
e27dfcea | 1619 | if (skb == NULL) |
1da177e4 LT |
1620 | goto out_err; |
1621 | ||
1622 | /* | |
1623 | * If you pass two values to the sock_alloc_send_skb | |
1624 | * it tries to grab the large buffer with GFP_NOFS | |
1625 | * (which can fail easily), and if it fails grab the | |
1626 | * fallback size buffer which is under a page and will | |
1627 | * succeed. [Alan] | |
1628 | */ | |
1629 | size = min_t(int, size, skb_tailroom(skb)); | |
1630 | ||
7361c36c | 1631 | |
8ba69ba6 | 1632 | /* Only send the fds in the first buffer */ |
7361c36c | 1633 | err = unix_scm_to_skb(siocb->scm, skb, !fds_sent); |
25888e30 | 1634 | if (err < 0) { |
7361c36c EB |
1635 | kfree_skb(skb); |
1636 | goto out_err; | |
6209344f | 1637 | } |
25888e30 | 1638 | max_level = err + 1; |
7361c36c | 1639 | fds_sent = true; |
1da177e4 | 1640 | |
6eba6a37 ED |
1641 | err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size); |
1642 | if (err) { | |
1da177e4 LT |
1643 | kfree_skb(skb); |
1644 | goto out_err; | |
1645 | } | |
1646 | ||
1c92b4e5 | 1647 | unix_state_lock(other); |
1da177e4 LT |
1648 | |
1649 | if (sock_flag(other, SOCK_DEAD) || | |
1650 | (other->sk_shutdown & RCV_SHUTDOWN)) | |
1651 | goto pipe_err_free; | |
1652 | ||
1653 | skb_queue_tail(&other->sk_receive_queue, skb); | |
25888e30 ED |
1654 | if (max_level > unix_sk(other)->recursion_level) |
1655 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1656 | unix_state_unlock(other); |
1da177e4 | 1657 | other->sk_data_ready(other, size); |
e27dfcea | 1658 | sent += size; |
1da177e4 | 1659 | } |
1da177e4 LT |
1660 | |
1661 | scm_destroy(siocb->scm); | |
1662 | siocb->scm = NULL; | |
1663 | ||
1664 | return sent; | |
1665 | ||
1666 | pipe_err_free: | |
1c92b4e5 | 1667 | unix_state_unlock(other); |
1da177e4 LT |
1668 | kfree_skb(skb); |
1669 | pipe_err: | |
6eba6a37 ED |
1670 | if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL)) |
1671 | send_sig(SIGPIPE, current, 0); | |
1da177e4 LT |
1672 | err = -EPIPE; |
1673 | out_err: | |
1da177e4 LT |
1674 | scm_destroy(siocb->scm); |
1675 | siocb->scm = NULL; | |
1676 | return sent ? : err; | |
1677 | } | |
1678 | ||
1679 | static int unix_seqpacket_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1680 | struct msghdr *msg, size_t len) | |
1681 | { | |
1682 | int err; | |
1683 | struct sock *sk = sock->sk; | |
ac7bfa62 | 1684 | |
1da177e4 LT |
1685 | err = sock_error(sk); |
1686 | if (err) | |
1687 | return err; | |
1688 | ||
1689 | if (sk->sk_state != TCP_ESTABLISHED) | |
1690 | return -ENOTCONN; | |
1691 | ||
1692 | if (msg->msg_namelen) | |
1693 | msg->msg_namelen = 0; | |
1694 | ||
1695 | return unix_dgram_sendmsg(kiocb, sock, msg, len); | |
1696 | } | |
ac7bfa62 | 1697 | |
1da177e4 LT |
1698 | static void unix_copy_addr(struct msghdr *msg, struct sock *sk) |
1699 | { | |
1700 | struct unix_sock *u = unix_sk(sk); | |
1701 | ||
1702 | msg->msg_namelen = 0; | |
1703 | if (u->addr) { | |
1704 | msg->msg_namelen = u->addr->len; | |
1705 | memcpy(msg->msg_name, u->addr->name, u->addr->len); | |
1706 | } | |
1707 | } | |
1708 | ||
1709 | static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1710 | struct msghdr *msg, size_t size, | |
1711 | int flags) | |
1712 | { | |
1713 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1714 | struct scm_cookie tmp_scm; | |
1715 | struct sock *sk = sock->sk; | |
1716 | struct unix_sock *u = unix_sk(sk); | |
1717 | int noblock = flags & MSG_DONTWAIT; | |
1718 | struct sk_buff *skb; | |
1719 | int err; | |
1720 | ||
1721 | err = -EOPNOTSUPP; | |
1722 | if (flags&MSG_OOB) | |
1723 | goto out; | |
1724 | ||
1725 | msg->msg_namelen = 0; | |
1726 | ||
57b47a53 | 1727 | mutex_lock(&u->readlock); |
1da177e4 LT |
1728 | |
1729 | skb = skb_recv_datagram(sk, flags, noblock, &err); | |
0a112258 FZ |
1730 | if (!skb) { |
1731 | unix_state_lock(sk); | |
1732 | /* Signal EOF on disconnected non-blocking SEQPACKET socket. */ | |
1733 | if (sk->sk_type == SOCK_SEQPACKET && err == -EAGAIN && | |
1734 | (sk->sk_shutdown & RCV_SHUTDOWN)) | |
1735 | err = 0; | |
1736 | unix_state_unlock(sk); | |
1da177e4 | 1737 | goto out_unlock; |
0a112258 | 1738 | } |
1da177e4 | 1739 | |
67426b75 ED |
1740 | wake_up_interruptible_sync_poll(&u->peer_wait, |
1741 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
1da177e4 LT |
1742 | |
1743 | if (msg->msg_name) | |
1744 | unix_copy_addr(msg, skb->sk); | |
1745 | ||
1746 | if (size > skb->len) | |
1747 | size = skb->len; | |
1748 | else if (size < skb->len) | |
1749 | msg->msg_flags |= MSG_TRUNC; | |
1750 | ||
1751 | err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, size); | |
1752 | if (err) | |
1753 | goto out_free; | |
1754 | ||
3f66116e AC |
1755 | if (sock_flag(sk, SOCK_RCVTSTAMP)) |
1756 | __sock_recv_timestamp(msg, sk, skb); | |
1757 | ||
1da177e4 LT |
1758 | if (!siocb->scm) { |
1759 | siocb->scm = &tmp_scm; | |
1760 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1761 | } | |
7361c36c | 1762 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
877ce7c1 | 1763 | unix_set_secdata(siocb->scm, skb); |
1da177e4 | 1764 | |
6eba6a37 | 1765 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
1766 | if (UNIXCB(skb).fp) |
1767 | unix_detach_fds(siocb->scm, skb); | |
6eba6a37 | 1768 | } else { |
1da177e4 LT |
1769 | /* It is questionable: on PEEK we could: |
1770 | - do not return fds - good, but too simple 8) | |
1771 | - return fds, and do not return them on read (old strategy, | |
1772 | apparently wrong) | |
1773 | - clone fds (I chose it for now, it is the most universal | |
1774 | solution) | |
ac7bfa62 YH |
1775 | |
1776 | POSIX 1003.1g does not actually define this clearly | |
1777 | at all. POSIX 1003.1g doesn't define a lot of things | |
1778 | clearly however! | |
1779 | ||
1da177e4 LT |
1780 | */ |
1781 | if (UNIXCB(skb).fp) | |
1782 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
1783 | } | |
1784 | err = size; | |
1785 | ||
1786 | scm_recv(sock, msg, siocb->scm, flags); | |
1787 | ||
1788 | out_free: | |
6eba6a37 | 1789 | skb_free_datagram(sk, skb); |
1da177e4 | 1790 | out_unlock: |
57b47a53 | 1791 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1792 | out: |
1793 | return err; | |
1794 | } | |
1795 | ||
1796 | /* | |
1797 | * Sleep until data has arrive. But check for races.. | |
1798 | */ | |
ac7bfa62 | 1799 | |
6eba6a37 | 1800 | static long unix_stream_data_wait(struct sock *sk, long timeo) |
1da177e4 LT |
1801 | { |
1802 | DEFINE_WAIT(wait); | |
1803 | ||
1c92b4e5 | 1804 | unix_state_lock(sk); |
1da177e4 LT |
1805 | |
1806 | for (;;) { | |
aa395145 | 1807 | prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); |
1da177e4 | 1808 | |
b03efcfb | 1809 | if (!skb_queue_empty(&sk->sk_receive_queue) || |
1da177e4 LT |
1810 | sk->sk_err || |
1811 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
1812 | signal_pending(current) || | |
1813 | !timeo) | |
1814 | break; | |
1815 | ||
1816 | set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); | |
1c92b4e5 | 1817 | unix_state_unlock(sk); |
1da177e4 | 1818 | timeo = schedule_timeout(timeo); |
1c92b4e5 | 1819 | unix_state_lock(sk); |
1da177e4 LT |
1820 | clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); |
1821 | } | |
1822 | ||
aa395145 | 1823 | finish_wait(sk_sleep(sk), &wait); |
1c92b4e5 | 1824 | unix_state_unlock(sk); |
1da177e4 LT |
1825 | return timeo; |
1826 | } | |
1827 | ||
1828 | ||
1829 | ||
1830 | static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1831 | struct msghdr *msg, size_t size, | |
1832 | int flags) | |
1833 | { | |
1834 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1835 | struct scm_cookie tmp_scm; | |
1836 | struct sock *sk = sock->sk; | |
1837 | struct unix_sock *u = unix_sk(sk); | |
e27dfcea | 1838 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1839 | int copied = 0; |
1840 | int check_creds = 0; | |
1841 | int target; | |
1842 | int err = 0; | |
1843 | long timeo; | |
1844 | ||
1845 | err = -EINVAL; | |
1846 | if (sk->sk_state != TCP_ESTABLISHED) | |
1847 | goto out; | |
1848 | ||
1849 | err = -EOPNOTSUPP; | |
1850 | if (flags&MSG_OOB) | |
1851 | goto out; | |
1852 | ||
1853 | target = sock_rcvlowat(sk, flags&MSG_WAITALL, size); | |
1854 | timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT); | |
1855 | ||
1856 | msg->msg_namelen = 0; | |
1857 | ||
1858 | /* Lock the socket to prevent queue disordering | |
1859 | * while sleeps in memcpy_tomsg | |
1860 | */ | |
1861 | ||
1862 | if (!siocb->scm) { | |
1863 | siocb->scm = &tmp_scm; | |
1864 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1865 | } | |
1866 | ||
57b47a53 | 1867 | mutex_lock(&u->readlock); |
1da177e4 | 1868 | |
6eba6a37 | 1869 | do { |
1da177e4 LT |
1870 | int chunk; |
1871 | struct sk_buff *skb; | |
1872 | ||
3c0d2f37 | 1873 | unix_state_lock(sk); |
1da177e4 | 1874 | skb = skb_dequeue(&sk->sk_receive_queue); |
6eba6a37 | 1875 | if (skb == NULL) { |
25888e30 | 1876 | unix_sk(sk)->recursion_level = 0; |
1da177e4 | 1877 | if (copied >= target) |
3c0d2f37 | 1878 | goto unlock; |
1da177e4 LT |
1879 | |
1880 | /* | |
1881 | * POSIX 1003.1g mandates this order. | |
1882 | */ | |
ac7bfa62 | 1883 | |
6eba6a37 ED |
1884 | err = sock_error(sk); |
1885 | if (err) | |
3c0d2f37 | 1886 | goto unlock; |
1da177e4 | 1887 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
3c0d2f37 MS |
1888 | goto unlock; |
1889 | ||
1890 | unix_state_unlock(sk); | |
1da177e4 LT |
1891 | err = -EAGAIN; |
1892 | if (!timeo) | |
1893 | break; | |
57b47a53 | 1894 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1895 | |
1896 | timeo = unix_stream_data_wait(sk, timeo); | |
1897 | ||
1898 | if (signal_pending(current)) { | |
1899 | err = sock_intr_errno(timeo); | |
1900 | goto out; | |
1901 | } | |
57b47a53 | 1902 | mutex_lock(&u->readlock); |
1da177e4 | 1903 | continue; |
3c0d2f37 MS |
1904 | unlock: |
1905 | unix_state_unlock(sk); | |
1906 | break; | |
1da177e4 | 1907 | } |
3c0d2f37 | 1908 | unix_state_unlock(sk); |
1da177e4 LT |
1909 | |
1910 | if (check_creds) { | |
1911 | /* Never glue messages from different writers */ | |
7361c36c EB |
1912 | if ((UNIXCB(skb).pid != siocb->scm->pid) || |
1913 | (UNIXCB(skb).cred != siocb->scm->cred)) { | |
1da177e4 LT |
1914 | skb_queue_head(&sk->sk_receive_queue, skb); |
1915 | break; | |
1916 | } | |
1917 | } else { | |
1918 | /* Copy credentials */ | |
7361c36c | 1919 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
1da177e4 LT |
1920 | check_creds = 1; |
1921 | } | |
1922 | ||
1923 | /* Copy address just once */ | |
6eba6a37 | 1924 | if (sunaddr) { |
1da177e4 LT |
1925 | unix_copy_addr(msg, skb->sk); |
1926 | sunaddr = NULL; | |
1927 | } | |
1928 | ||
1929 | chunk = min_t(unsigned int, skb->len, size); | |
1930 | if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) { | |
1931 | skb_queue_head(&sk->sk_receive_queue, skb); | |
1932 | if (copied == 0) | |
1933 | copied = -EFAULT; | |
1934 | break; | |
1935 | } | |
1936 | copied += chunk; | |
1937 | size -= chunk; | |
1938 | ||
1939 | /* Mark read part of skb as used */ | |
6eba6a37 | 1940 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
1941 | skb_pull(skb, chunk); |
1942 | ||
1943 | if (UNIXCB(skb).fp) | |
1944 | unix_detach_fds(siocb->scm, skb); | |
1945 | ||
1946 | /* put the skb back if we didn't use it up.. */ | |
6eba6a37 | 1947 | if (skb->len) { |
1da177e4 LT |
1948 | skb_queue_head(&sk->sk_receive_queue, skb); |
1949 | break; | |
1950 | } | |
1951 | ||
70d4bf6d | 1952 | consume_skb(skb); |
1da177e4 LT |
1953 | |
1954 | if (siocb->scm->fp) | |
1955 | break; | |
6eba6a37 | 1956 | } else { |
1da177e4 LT |
1957 | /* It is questionable, see note in unix_dgram_recvmsg. |
1958 | */ | |
1959 | if (UNIXCB(skb).fp) | |
1960 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
1961 | ||
1962 | /* put message back and return */ | |
1963 | skb_queue_head(&sk->sk_receive_queue, skb); | |
1964 | break; | |
1965 | } | |
1966 | } while (size); | |
1967 | ||
57b47a53 | 1968 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1969 | scm_recv(sock, msg, siocb->scm, flags); |
1970 | out: | |
1971 | return copied ? : err; | |
1972 | } | |
1973 | ||
1974 | static int unix_shutdown(struct socket *sock, int mode) | |
1975 | { | |
1976 | struct sock *sk = sock->sk; | |
1977 | struct sock *other; | |
1978 | ||
1979 | mode = (mode+1)&(RCV_SHUTDOWN|SEND_SHUTDOWN); | |
1980 | ||
1981 | if (mode) { | |
1c92b4e5 | 1982 | unix_state_lock(sk); |
1da177e4 | 1983 | sk->sk_shutdown |= mode; |
e27dfcea | 1984 | other = unix_peer(sk); |
1da177e4 LT |
1985 | if (other) |
1986 | sock_hold(other); | |
1c92b4e5 | 1987 | unix_state_unlock(sk); |
1da177e4 LT |
1988 | sk->sk_state_change(sk); |
1989 | ||
1990 | if (other && | |
1991 | (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)) { | |
1992 | ||
1993 | int peer_mode = 0; | |
1994 | ||
1995 | if (mode&RCV_SHUTDOWN) | |
1996 | peer_mode |= SEND_SHUTDOWN; | |
1997 | if (mode&SEND_SHUTDOWN) | |
1998 | peer_mode |= RCV_SHUTDOWN; | |
1c92b4e5 | 1999 | unix_state_lock(other); |
1da177e4 | 2000 | other->sk_shutdown |= peer_mode; |
1c92b4e5 | 2001 | unix_state_unlock(other); |
1da177e4 | 2002 | other->sk_state_change(other); |
1da177e4 | 2003 | if (peer_mode == SHUTDOWN_MASK) |
8d8ad9d7 | 2004 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_HUP); |
1da177e4 | 2005 | else if (peer_mode & RCV_SHUTDOWN) |
8d8ad9d7 | 2006 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_IN); |
1da177e4 LT |
2007 | } |
2008 | if (other) | |
2009 | sock_put(other); | |
2010 | } | |
2011 | return 0; | |
2012 | } | |
2013 | ||
2014 | static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) | |
2015 | { | |
2016 | struct sock *sk = sock->sk; | |
e27dfcea | 2017 | long amount = 0; |
1da177e4 LT |
2018 | int err; |
2019 | ||
6eba6a37 ED |
2020 | switch (cmd) { |
2021 | case SIOCOUTQ: | |
31e6d363 | 2022 | amount = sk_wmem_alloc_get(sk); |
6eba6a37 ED |
2023 | err = put_user(amount, (int __user *)arg); |
2024 | break; | |
2025 | case SIOCINQ: | |
1da177e4 LT |
2026 | { |
2027 | struct sk_buff *skb; | |
2028 | ||
2029 | if (sk->sk_state == TCP_LISTEN) { | |
2030 | err = -EINVAL; | |
2031 | break; | |
2032 | } | |
2033 | ||
2034 | spin_lock(&sk->sk_receive_queue.lock); | |
2035 | if (sk->sk_type == SOCK_STREAM || | |
2036 | sk->sk_type == SOCK_SEQPACKET) { | |
2037 | skb_queue_walk(&sk->sk_receive_queue, skb) | |
2038 | amount += skb->len; | |
2039 | } else { | |
2040 | skb = skb_peek(&sk->sk_receive_queue); | |
2041 | if (skb) | |
e27dfcea | 2042 | amount = skb->len; |
1da177e4 LT |
2043 | } |
2044 | spin_unlock(&sk->sk_receive_queue.lock); | |
2045 | err = put_user(amount, (int __user *)arg); | |
2046 | break; | |
2047 | } | |
2048 | ||
6eba6a37 ED |
2049 | default: |
2050 | err = -ENOIOCTLCMD; | |
2051 | break; | |
1da177e4 LT |
2052 | } |
2053 | return err; | |
2054 | } | |
2055 | ||
6eba6a37 | 2056 | static unsigned int unix_poll(struct file *file, struct socket *sock, poll_table *wait) |
1da177e4 LT |
2057 | { |
2058 | struct sock *sk = sock->sk; | |
2059 | unsigned int mask; | |
2060 | ||
aa395145 | 2061 | sock_poll_wait(file, sk_sleep(sk), wait); |
1da177e4 LT |
2062 | mask = 0; |
2063 | ||
2064 | /* exceptional events? */ | |
2065 | if (sk->sk_err) | |
2066 | mask |= POLLERR; | |
2067 | if (sk->sk_shutdown == SHUTDOWN_MASK) | |
2068 | mask |= POLLHUP; | |
f348d70a | 2069 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
db40980f | 2070 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
1da177e4 LT |
2071 | |
2072 | /* readable? */ | |
db40980f | 2073 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
1da177e4 LT |
2074 | mask |= POLLIN | POLLRDNORM; |
2075 | ||
2076 | /* Connection-based need to check for termination and startup */ | |
6eba6a37 ED |
2077 | if ((sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) && |
2078 | sk->sk_state == TCP_CLOSE) | |
1da177e4 LT |
2079 | mask |= POLLHUP; |
2080 | ||
2081 | /* | |
2082 | * we set writable also when the other side has shut down the | |
2083 | * connection. This prevents stuck sockets. | |
2084 | */ | |
2085 | if (unix_writable(sk)) | |
2086 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; | |
2087 | ||
2088 | return mask; | |
2089 | } | |
2090 | ||
ec0d215f RW |
2091 | static unsigned int unix_dgram_poll(struct file *file, struct socket *sock, |
2092 | poll_table *wait) | |
3c73419c | 2093 | { |
ec0d215f RW |
2094 | struct sock *sk = sock->sk, *other; |
2095 | unsigned int mask, writable; | |
3c73419c | 2096 | |
aa395145 | 2097 | sock_poll_wait(file, sk_sleep(sk), wait); |
3c73419c RW |
2098 | mask = 0; |
2099 | ||
2100 | /* exceptional events? */ | |
2101 | if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue)) | |
2102 | mask |= POLLERR; | |
2103 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
5456f09a | 2104 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
3c73419c RW |
2105 | if (sk->sk_shutdown == SHUTDOWN_MASK) |
2106 | mask |= POLLHUP; | |
2107 | ||
2108 | /* readable? */ | |
5456f09a | 2109 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
3c73419c RW |
2110 | mask |= POLLIN | POLLRDNORM; |
2111 | ||
2112 | /* Connection-based need to check for termination and startup */ | |
2113 | if (sk->sk_type == SOCK_SEQPACKET) { | |
2114 | if (sk->sk_state == TCP_CLOSE) | |
2115 | mask |= POLLHUP; | |
2116 | /* connection hasn't started yet? */ | |
2117 | if (sk->sk_state == TCP_SYN_SENT) | |
2118 | return mask; | |
2119 | } | |
2120 | ||
973a34aa ED |
2121 | /* No write status requested, avoid expensive OUT tests. */ |
2122 | if (wait && !(wait->key & (POLLWRBAND | POLLWRNORM | POLLOUT))) | |
2123 | return mask; | |
2124 | ||
ec0d215f | 2125 | writable = unix_writable(sk); |
5456f09a ED |
2126 | other = unix_peer_get(sk); |
2127 | if (other) { | |
2128 | if (unix_peer(other) != sk) { | |
2129 | sock_poll_wait(file, &unix_sk(other)->peer_wait, wait); | |
2130 | if (unix_recvq_full(other)) | |
2131 | writable = 0; | |
ec0d215f | 2132 | } |
5456f09a | 2133 | sock_put(other); |
ec0d215f RW |
2134 | } |
2135 | ||
2136 | if (writable) | |
3c73419c RW |
2137 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; |
2138 | else | |
2139 | set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
2140 | ||
3c73419c RW |
2141 | return mask; |
2142 | } | |
1da177e4 LT |
2143 | |
2144 | #ifdef CONFIG_PROC_FS | |
a53eb3fe PE |
2145 | static struct sock *first_unix_socket(int *i) |
2146 | { | |
2147 | for (*i = 0; *i <= UNIX_HASH_SIZE; (*i)++) { | |
2148 | if (!hlist_empty(&unix_socket_table[*i])) | |
2149 | return __sk_head(&unix_socket_table[*i]); | |
2150 | } | |
2151 | return NULL; | |
2152 | } | |
2153 | ||
2154 | static struct sock *next_unix_socket(int *i, struct sock *s) | |
2155 | { | |
2156 | struct sock *next = sk_next(s); | |
2157 | /* More in this chain? */ | |
2158 | if (next) | |
2159 | return next; | |
2160 | /* Look for next non-empty chain. */ | |
2161 | for ((*i)++; *i <= UNIX_HASH_SIZE; (*i)++) { | |
2162 | if (!hlist_empty(&unix_socket_table[*i])) | |
2163 | return __sk_head(&unix_socket_table[*i]); | |
2164 | } | |
2165 | return NULL; | |
2166 | } | |
2167 | ||
097e66c5 | 2168 | struct unix_iter_state { |
e372c414 | 2169 | struct seq_net_private p; |
097e66c5 DL |
2170 | int i; |
2171 | }; | |
e27dfcea | 2172 | |
1218854a | 2173 | static struct sock *unix_seq_idx(struct seq_file *seq, loff_t pos) |
1da177e4 | 2174 | { |
1218854a | 2175 | struct unix_iter_state *iter = seq->private; |
1da177e4 LT |
2176 | loff_t off = 0; |
2177 | struct sock *s; | |
2178 | ||
097e66c5 | 2179 | for (s = first_unix_socket(&iter->i); s; s = next_unix_socket(&iter->i, s)) { |
1218854a | 2180 | if (sock_net(s) != seq_file_net(seq)) |
097e66c5 | 2181 | continue; |
ac7bfa62 | 2182 | if (off == pos) |
1da177e4 LT |
2183 | return s; |
2184 | ++off; | |
2185 | } | |
2186 | return NULL; | |
2187 | } | |
2188 | ||
1da177e4 | 2189 | static void *unix_seq_start(struct seq_file *seq, loff_t *pos) |
9a429c49 | 2190 | __acquires(unix_table_lock) |
1da177e4 | 2191 | { |
fbe9cc4a | 2192 | spin_lock(&unix_table_lock); |
b9f3124f | 2193 | return *pos ? unix_seq_idx(seq, *pos - 1) : SEQ_START_TOKEN; |
1da177e4 LT |
2194 | } |
2195 | ||
2196 | static void *unix_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2197 | { | |
097e66c5 DL |
2198 | struct unix_iter_state *iter = seq->private; |
2199 | struct sock *sk = v; | |
1da177e4 LT |
2200 | ++*pos; |
2201 | ||
b9f3124f | 2202 | if (v == SEQ_START_TOKEN) |
097e66c5 DL |
2203 | sk = first_unix_socket(&iter->i); |
2204 | else | |
2205 | sk = next_unix_socket(&iter->i, sk); | |
1218854a | 2206 | while (sk && (sock_net(sk) != seq_file_net(seq))) |
097e66c5 DL |
2207 | sk = next_unix_socket(&iter->i, sk); |
2208 | return sk; | |
1da177e4 LT |
2209 | } |
2210 | ||
2211 | static void unix_seq_stop(struct seq_file *seq, void *v) | |
9a429c49 | 2212 | __releases(unix_table_lock) |
1da177e4 | 2213 | { |
fbe9cc4a | 2214 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
2215 | } |
2216 | ||
2217 | static int unix_seq_show(struct seq_file *seq, void *v) | |
2218 | { | |
ac7bfa62 | 2219 | |
b9f3124f | 2220 | if (v == SEQ_START_TOKEN) |
1da177e4 LT |
2221 | seq_puts(seq, "Num RefCount Protocol Flags Type St " |
2222 | "Inode Path\n"); | |
2223 | else { | |
2224 | struct sock *s = v; | |
2225 | struct unix_sock *u = unix_sk(s); | |
1c92b4e5 | 2226 | unix_state_lock(s); |
1da177e4 LT |
2227 | |
2228 | seq_printf(seq, "%p: %08X %08X %08X %04X %02X %5lu", | |
2229 | s, | |
2230 | atomic_read(&s->sk_refcnt), | |
2231 | 0, | |
2232 | s->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0, | |
2233 | s->sk_type, | |
2234 | s->sk_socket ? | |
2235 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) : | |
2236 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING), | |
2237 | sock_i_ino(s)); | |
2238 | ||
2239 | if (u->addr) { | |
2240 | int i, len; | |
2241 | seq_putc(seq, ' '); | |
2242 | ||
2243 | i = 0; | |
2244 | len = u->addr->len - sizeof(short); | |
2245 | if (!UNIX_ABSTRACT(s)) | |
2246 | len--; | |
2247 | else { | |
2248 | seq_putc(seq, '@'); | |
2249 | i++; | |
2250 | } | |
2251 | for ( ; i < len; i++) | |
2252 | seq_putc(seq, u->addr->name->sun_path[i]); | |
2253 | } | |
1c92b4e5 | 2254 | unix_state_unlock(s); |
1da177e4 LT |
2255 | seq_putc(seq, '\n'); |
2256 | } | |
2257 | ||
2258 | return 0; | |
2259 | } | |
2260 | ||
56b3d975 | 2261 | static const struct seq_operations unix_seq_ops = { |
1da177e4 LT |
2262 | .start = unix_seq_start, |
2263 | .next = unix_seq_next, | |
2264 | .stop = unix_seq_stop, | |
2265 | .show = unix_seq_show, | |
2266 | }; | |
2267 | ||
1da177e4 LT |
2268 | static int unix_seq_open(struct inode *inode, struct file *file) |
2269 | { | |
e372c414 DL |
2270 | return seq_open_net(inode, file, &unix_seq_ops, |
2271 | sizeof(struct unix_iter_state)); | |
1da177e4 LT |
2272 | } |
2273 | ||
da7071d7 | 2274 | static const struct file_operations unix_seq_fops = { |
1da177e4 LT |
2275 | .owner = THIS_MODULE, |
2276 | .open = unix_seq_open, | |
2277 | .read = seq_read, | |
2278 | .llseek = seq_lseek, | |
e372c414 | 2279 | .release = seq_release_net, |
1da177e4 LT |
2280 | }; |
2281 | ||
2282 | #endif | |
2283 | ||
ec1b4cf7 | 2284 | static const struct net_proto_family unix_family_ops = { |
1da177e4 LT |
2285 | .family = PF_UNIX, |
2286 | .create = unix_create, | |
2287 | .owner = THIS_MODULE, | |
2288 | }; | |
2289 | ||
097e66c5 | 2290 | |
2c8c1e72 | 2291 | static int __net_init unix_net_init(struct net *net) |
097e66c5 DL |
2292 | { |
2293 | int error = -ENOMEM; | |
2294 | ||
a0a53c8b | 2295 | net->unx.sysctl_max_dgram_qlen = 10; |
1597fbc0 PE |
2296 | if (unix_sysctl_register(net)) |
2297 | goto out; | |
d392e497 | 2298 | |
097e66c5 | 2299 | #ifdef CONFIG_PROC_FS |
1597fbc0 PE |
2300 | if (!proc_net_fops_create(net, "unix", 0, &unix_seq_fops)) { |
2301 | unix_sysctl_unregister(net); | |
097e66c5 | 2302 | goto out; |
1597fbc0 | 2303 | } |
097e66c5 DL |
2304 | #endif |
2305 | error = 0; | |
2306 | out: | |
48dcc33e | 2307 | return error; |
097e66c5 DL |
2308 | } |
2309 | ||
2c8c1e72 | 2310 | static void __net_exit unix_net_exit(struct net *net) |
097e66c5 | 2311 | { |
1597fbc0 | 2312 | unix_sysctl_unregister(net); |
097e66c5 DL |
2313 | proc_net_remove(net, "unix"); |
2314 | } | |
2315 | ||
2316 | static struct pernet_operations unix_net_ops = { | |
2317 | .init = unix_net_init, | |
2318 | .exit = unix_net_exit, | |
2319 | }; | |
2320 | ||
1da177e4 LT |
2321 | static int __init af_unix_init(void) |
2322 | { | |
2323 | int rc = -1; | |
2324 | struct sk_buff *dummy_skb; | |
2325 | ||
ef047f5e | 2326 | BUILD_BUG_ON(sizeof(struct unix_skb_parms) > sizeof(dummy_skb->cb)); |
1da177e4 LT |
2327 | |
2328 | rc = proto_register(&unix_proto, 1); | |
ac7bfa62 YH |
2329 | if (rc != 0) { |
2330 | printk(KERN_CRIT "%s: Cannot create unix_sock SLAB cache!\n", | |
0dc47877 | 2331 | __func__); |
1da177e4 LT |
2332 | goto out; |
2333 | } | |
2334 | ||
2335 | sock_register(&unix_family_ops); | |
097e66c5 | 2336 | register_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2337 | out: |
2338 | return rc; | |
2339 | } | |
2340 | ||
2341 | static void __exit af_unix_exit(void) | |
2342 | { | |
2343 | sock_unregister(PF_UNIX); | |
1da177e4 | 2344 | proto_unregister(&unix_proto); |
097e66c5 | 2345 | unregister_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2346 | } |
2347 | ||
3d366960 DW |
2348 | /* Earlier than device_initcall() so that other drivers invoking |
2349 | request_module() don't end up in a loop when modprobe tries | |
2350 | to use a UNIX socket. But later than subsys_initcall() because | |
2351 | we depend on stuff initialised there */ | |
2352 | fs_initcall(af_unix_init); | |
1da177e4 LT |
2353 | module_exit(af_unix_exit); |
2354 | ||
2355 | MODULE_LICENSE("GPL"); | |
2356 | MODULE_ALIAS_NETPROTO(PF_UNIX); |