1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * File: socket.c
4 *
5 * Phonet sockets
6 *
7 * Copyright (C) 2008 Nokia Corporation.
8 *
9 * Authors: Sakari Ailus <sakari.ailus@nokia.com>
10 * Rémi Denis-Courmont
11 */
12
13 #include <linux/gfp.h>
14 #include <linux/kernel.h>
15 #include <linux/net.h>
16 #include <linux/poll.h>
17 #include <linux/sched/signal.h>
18
19 #include <net/sock.h>
20 #include <net/tcp_states.h>
21
22 #include <linux/phonet.h>
23 #include <linux/export.h>
24 #include <net/phonet/phonet.h>
25 #include <net/phonet/pep.h>
26 #include <net/phonet/pn_dev.h>
27
pn_socket_release(struct socket * sock)28 static int pn_socket_release(struct socket *sock)
29 {
30 struct sock *sk = sock->sk;
31
32 if (sk) {
33 sock->sk = NULL;
34 sk->sk_prot->close(sk, 0);
35 }
36 return 0;
37 }
38
39 #define PN_HASHSIZE 16
40 #define PN_HASHMASK (PN_HASHSIZE-1)
41
42
43 static struct {
44 struct hlist_head hlist[PN_HASHSIZE];
45 struct mutex lock;
46 } pnsocks;
47
pn_sock_init(void)48 void __init pn_sock_init(void)
49 {
50 unsigned int i;
51
52 for (i = 0; i < PN_HASHSIZE; i++)
53 INIT_HLIST_HEAD(pnsocks.hlist + i);
54 mutex_init(&pnsocks.lock);
55 }
56
pn_hash_list(u16 obj)57 static struct hlist_head *pn_hash_list(u16 obj)
58 {
59 return pnsocks.hlist + (obj & PN_HASHMASK);
60 }
61
62 /*
63 * Find address based on socket address, match only certain fields.
64 * Also grab sock if it was found. Remember to sock_put it later.
65 */
pn_find_sock_by_sa(struct net * net,const struct sockaddr_pn * spn)66 struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn)
67 {
68 struct sock *sknode;
69 struct sock *rval = NULL;
70 u16 obj = pn_sockaddr_get_object(spn);
71 u8 res = spn->spn_resource;
72 struct hlist_head *hlist = pn_hash_list(obj);
73
74 rcu_read_lock();
75 sk_for_each_rcu(sknode, hlist) {
76 struct pn_sock *pn = pn_sk(sknode);
77 BUG_ON(!pn->sobject); /* unbound socket */
78
79 if (!net_eq(sock_net(sknode), net))
80 continue;
81 if (pn_port(obj)) {
82 /* Look up socket by port */
83 if (pn_port(pn->sobject) != pn_port(obj))
84 continue;
85 } else {
86 /* If port is zero, look up by resource */
87 if (pn->resource != res)
88 continue;
89 }
90 if (pn_addr(pn->sobject) &&
91 pn_addr(pn->sobject) != pn_addr(obj))
92 continue;
93
94 rval = sknode;
95 sock_hold(sknode);
96 break;
97 }
98 rcu_read_unlock();
99
100 return rval;
101 }
102
103 /* Deliver a broadcast packet (only in bottom-half) */
pn_deliver_sock_broadcast(struct net * net,struct sk_buff * skb)104 void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb)
105 {
106 struct hlist_head *hlist = pnsocks.hlist;
107 unsigned int h;
108
109 rcu_read_lock();
110 for (h = 0; h < PN_HASHSIZE; h++) {
111 struct sock *sknode;
112
113 sk_for_each(sknode, hlist) {
114 struct sk_buff *clone;
115
116 if (!net_eq(sock_net(sknode), net))
117 continue;
118 if (!sock_flag(sknode, SOCK_BROADCAST))
119 continue;
120
121 clone = skb_clone(skb, GFP_ATOMIC);
122 if (clone) {
123 sock_hold(sknode);
124 sk_receive_skb(sknode, clone, 0);
125 }
126 }
127 hlist++;
128 }
129 rcu_read_unlock();
130 }
131
pn_sock_hash(struct sock * sk)132 int pn_sock_hash(struct sock *sk)
133 {
134 struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject);
135
136 mutex_lock(&pnsocks.lock);
137 sk_add_node_rcu(sk, hlist);
138 mutex_unlock(&pnsocks.lock);
139
140 return 0;
141 }
142 EXPORT_SYMBOL(pn_sock_hash);
143
pn_sock_unhash(struct sock * sk)144 void pn_sock_unhash(struct sock *sk)
145 {
146 mutex_lock(&pnsocks.lock);
147 sk_del_node_init_rcu(sk);
148 mutex_unlock(&pnsocks.lock);
149 pn_sock_unbind_all_res(sk);
150 synchronize_rcu();
151 }
152 EXPORT_SYMBOL(pn_sock_unhash);
153
154 static DEFINE_MUTEX(port_mutex);
155
pn_socket_bind(struct socket * sock,struct sockaddr * addr,int len)156 static int pn_socket_bind(struct socket *sock, struct sockaddr *addr, int len)
157 {
158 struct sock *sk = sock->sk;
159 struct pn_sock *pn = pn_sk(sk);
160 struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
161 int err;
162 u16 handle;
163 u8 saddr;
164
165 if (sk->sk_prot->bind)
166 return sk->sk_prot->bind(sk, addr, len);
167
168 if (len < sizeof(struct sockaddr_pn))
169 return -EINVAL;
170 if (spn->spn_family != AF_PHONET)
171 return -EAFNOSUPPORT;
172
173 handle = pn_sockaddr_get_object((struct sockaddr_pn *)addr);
174 saddr = pn_addr(handle);
175 if (saddr && phonet_address_lookup(sock_net(sk), saddr))
176 return -EADDRNOTAVAIL;
177
178 lock_sock(sk);
179 if (sk->sk_state != TCP_CLOSE || pn_port(pn->sobject)) {
180 err = -EINVAL; /* attempt to rebind */
181 goto out;
182 }
183 WARN_ON(sk_hashed(sk));
184 mutex_lock(&port_mutex);
185 err = sk->sk_prot->get_port(sk, pn_port(handle));
186 if (err)
187 goto out_port;
188
189 /* get_port() sets the port, bind() sets the address if applicable */
190 pn->sobject = pn_object(saddr, pn_port(pn->sobject));
191 pn->resource = spn->spn_resource;
192
193 /* Enable RX on the socket */
194 err = sk->sk_prot->hash(sk);
195 out_port:
196 mutex_unlock(&port_mutex);
197 out:
198 release_sock(sk);
199 return err;
200 }
201
pn_socket_autobind(struct socket * sock)202 static int pn_socket_autobind(struct socket *sock)
203 {
204 struct sockaddr_pn sa;
205 int err;
206
207 memset(&sa, 0, sizeof(sa));
208 sa.spn_family = AF_PHONET;
209 err = pn_socket_bind(sock, (struct sockaddr *)&sa,
210 sizeof(struct sockaddr_pn));
211 if (err != -EINVAL)
212 return err;
213 BUG_ON(!pn_port(pn_sk(sock->sk)->sobject));
214 return 0; /* socket was already bound */
215 }
216
pn_socket_connect(struct socket * sock,struct sockaddr * addr,int len,int flags)217 static int pn_socket_connect(struct socket *sock, struct sockaddr *addr,
218 int len, int flags)
219 {
220 struct sock *sk = sock->sk;
221 struct pn_sock *pn = pn_sk(sk);
222 struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
223 struct task_struct *tsk = current;
224 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
225 int err;
226
227 if (pn_socket_autobind(sock))
228 return -ENOBUFS;
229 if (len < sizeof(struct sockaddr_pn))
230 return -EINVAL;
231 if (spn->spn_family != AF_PHONET)
232 return -EAFNOSUPPORT;
233
234 lock_sock(sk);
235
236 switch (sock->state) {
237 case SS_UNCONNECTED:
238 if (sk->sk_state != TCP_CLOSE) {
239 err = -EISCONN;
240 goto out;
241 }
242 break;
243 case SS_CONNECTING:
244 err = -EALREADY;
245 goto out;
246 default:
247 err = -EISCONN;
248 goto out;
249 }
250
251 pn->dobject = pn_sockaddr_get_object(spn);
252 pn->resource = pn_sockaddr_get_resource(spn);
253 sock->state = SS_CONNECTING;
254
255 err = sk->sk_prot->connect(sk, addr, len);
256 if (err) {
257 sock->state = SS_UNCONNECTED;
258 pn->dobject = 0;
259 goto out;
260 }
261
262 while (sk->sk_state == TCP_SYN_SENT) {
263 DEFINE_WAIT(wait);
264
265 if (!timeo) {
266 err = -EINPROGRESS;
267 goto out;
268 }
269 if (signal_pending(tsk)) {
270 err = sock_intr_errno(timeo);
271 goto out;
272 }
273
274 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
275 TASK_INTERRUPTIBLE);
276 release_sock(sk);
277 timeo = schedule_timeout(timeo);
278 lock_sock(sk);
279 finish_wait(sk_sleep(sk), &wait);
280 }
281
282 if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
283 err = 0;
284 else if (sk->sk_state == TCP_CLOSE_WAIT)
285 err = -ECONNRESET;
286 else
287 err = -ECONNREFUSED;
288 sock->state = err ? SS_UNCONNECTED : SS_CONNECTED;
289 out:
290 release_sock(sk);
291 return err;
292 }
293
pn_socket_accept(struct socket * sock,struct socket * newsock,int flags,bool kern)294 static int pn_socket_accept(struct socket *sock, struct socket *newsock,
295 int flags, bool kern)
296 {
297 struct sock *sk = sock->sk;
298 struct sock *newsk;
299 int err;
300
301 if (unlikely(sk->sk_state != TCP_LISTEN))
302 return -EINVAL;
303
304 newsk = sk->sk_prot->accept(sk, flags, &err, kern);
305 if (!newsk)
306 return err;
307
308 lock_sock(newsk);
309 sock_graft(newsk, newsock);
310 newsock->state = SS_CONNECTED;
311 release_sock(newsk);
312 return 0;
313 }
314
pn_socket_getname(struct socket * sock,struct sockaddr * addr,int peer)315 static int pn_socket_getname(struct socket *sock, struct sockaddr *addr,
316 int peer)
317 {
318 struct sock *sk = sock->sk;
319 struct pn_sock *pn = pn_sk(sk);
320
321 memset(addr, 0, sizeof(struct sockaddr_pn));
322 addr->sa_family = AF_PHONET;
323 if (!peer) /* Race with bind() here is userland's problem. */
324 pn_sockaddr_set_object((struct sockaddr_pn *)addr,
325 pn->sobject);
326
327 return sizeof(struct sockaddr_pn);
328 }
329
pn_socket_poll(struct file * file,struct socket * sock,poll_table * wait)330 static __poll_t pn_socket_poll(struct file *file, struct socket *sock,
331 poll_table *wait)
332 {
333 struct sock *sk = sock->sk;
334 struct pep_sock *pn = pep_sk(sk);
335 __poll_t mask = 0;
336
337 poll_wait(file, sk_sleep(sk), wait);
338
339 if (sk->sk_state == TCP_CLOSE)
340 return EPOLLERR;
341 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
342 mask |= EPOLLIN | EPOLLRDNORM;
343 if (!skb_queue_empty_lockless(&pn->ctrlreq_queue))
344 mask |= EPOLLPRI;
345 if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
346 return EPOLLHUP;
347
348 if (sk->sk_state == TCP_ESTABLISHED &&
349 refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf &&
350 atomic_read(&pn->tx_credits))
351 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
352
353 return mask;
354 }
355
pn_socket_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)356 static int pn_socket_ioctl(struct socket *sock, unsigned int cmd,
357 unsigned long arg)
358 {
359 struct sock *sk = sock->sk;
360 struct pn_sock *pn = pn_sk(sk);
361
362 if (cmd == SIOCPNGETOBJECT) {
363 struct net_device *dev;
364 u16 handle;
365 u8 saddr;
366
367 if (get_user(handle, (__u16 __user *)arg))
368 return -EFAULT;
369
370 lock_sock(sk);
371 if (sk->sk_bound_dev_if)
372 dev = dev_get_by_index(sock_net(sk),
373 sk->sk_bound_dev_if);
374 else
375 dev = phonet_device_get(sock_net(sk));
376 if (dev && (dev->flags & IFF_UP))
377 saddr = phonet_address_get(dev, pn_addr(handle));
378 else
379 saddr = PN_NO_ADDR;
380 release_sock(sk);
381
382 dev_put(dev);
383 if (saddr == PN_NO_ADDR)
384 return -EHOSTUNREACH;
385
386 handle = pn_object(saddr, pn_port(pn->sobject));
387 return put_user(handle, (__u16 __user *)arg);
388 }
389
390 return sk_ioctl(sk, cmd, (void __user *)arg);
391 }
392
pn_socket_listen(struct socket * sock,int backlog)393 static int pn_socket_listen(struct socket *sock, int backlog)
394 {
395 struct sock *sk = sock->sk;
396 int err = 0;
397
398 if (pn_socket_autobind(sock))
399 return -ENOBUFS;
400
401 lock_sock(sk);
402 if (sock->state != SS_UNCONNECTED) {
403 err = -EINVAL;
404 goto out;
405 }
406
407 if (sk->sk_state != TCP_LISTEN) {
408 sk->sk_state = TCP_LISTEN;
409 sk->sk_ack_backlog = 0;
410 }
411 sk->sk_max_ack_backlog = backlog;
412 out:
413 release_sock(sk);
414 return err;
415 }
416
pn_socket_sendmsg(struct socket * sock,struct msghdr * m,size_t total_len)417 static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m,
418 size_t total_len)
419 {
420 struct sock *sk = sock->sk;
421
422 if (pn_socket_autobind(sock))
423 return -EAGAIN;
424
425 return sk->sk_prot->sendmsg(sk, m, total_len);
426 }
427
428 const struct proto_ops phonet_dgram_ops = {
429 .family = AF_PHONET,
430 .owner = THIS_MODULE,
431 .release = pn_socket_release,
432 .bind = pn_socket_bind,
433 .connect = sock_no_connect,
434 .socketpair = sock_no_socketpair,
435 .accept = sock_no_accept,
436 .getname = pn_socket_getname,
437 .poll = datagram_poll,
438 .ioctl = pn_socket_ioctl,
439 .listen = sock_no_listen,
440 .shutdown = sock_no_shutdown,
441 .sendmsg = pn_socket_sendmsg,
442 .recvmsg = sock_common_recvmsg,
443 .mmap = sock_no_mmap,
444 };
445
446 const struct proto_ops phonet_stream_ops = {
447 .family = AF_PHONET,
448 .owner = THIS_MODULE,
449 .release = pn_socket_release,
450 .bind = pn_socket_bind,
451 .connect = pn_socket_connect,
452 .socketpair = sock_no_socketpair,
453 .accept = pn_socket_accept,
454 .getname = pn_socket_getname,
455 .poll = pn_socket_poll,
456 .ioctl = pn_socket_ioctl,
457 .listen = pn_socket_listen,
458 .shutdown = sock_no_shutdown,
459 .setsockopt = sock_common_setsockopt,
460 .getsockopt = sock_common_getsockopt,
461 .sendmsg = pn_socket_sendmsg,
462 .recvmsg = sock_common_recvmsg,
463 .mmap = sock_no_mmap,
464 };
465 EXPORT_SYMBOL(phonet_stream_ops);
466
467 /* allocate port for a socket */
pn_sock_get_port(struct sock * sk,unsigned short sport)468 int pn_sock_get_port(struct sock *sk, unsigned short sport)
469 {
470 static int port_cur;
471 struct net *net = sock_net(sk);
472 struct pn_sock *pn = pn_sk(sk);
473 struct sockaddr_pn try_sa;
474 struct sock *tmpsk;
475
476 memset(&try_sa, 0, sizeof(struct sockaddr_pn));
477 try_sa.spn_family = AF_PHONET;
478 WARN_ON(!mutex_is_locked(&port_mutex));
479 if (!sport) {
480 /* search free port */
481 int port, pmin, pmax;
482
483 phonet_get_local_port_range(&pmin, &pmax);
484 for (port = pmin; port <= pmax; port++) {
485 port_cur++;
486 if (port_cur < pmin || port_cur > pmax)
487 port_cur = pmin;
488
489 pn_sockaddr_set_port(&try_sa, port_cur);
490 tmpsk = pn_find_sock_by_sa(net, &try_sa);
491 if (tmpsk == NULL) {
492 sport = port_cur;
493 goto found;
494 } else
495 sock_put(tmpsk);
496 }
497 } else {
498 /* try to find specific port */
499 pn_sockaddr_set_port(&try_sa, sport);
500 tmpsk = pn_find_sock_by_sa(net, &try_sa);
501 if (tmpsk == NULL)
502 /* No sock there! We can use that port... */
503 goto found;
504 else
505 sock_put(tmpsk);
506 }
507 /* the port must be in use already */
508 return -EADDRINUSE;
509
510 found:
511 pn->sobject = pn_object(pn_addr(pn->sobject), sport);
512 return 0;
513 }
514 EXPORT_SYMBOL(pn_sock_get_port);
515
516 #ifdef CONFIG_PROC_FS
pn_sock_get_idx(struct seq_file * seq,loff_t pos)517 static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos)
518 {
519 struct net *net = seq_file_net(seq);
520 struct hlist_head *hlist = pnsocks.hlist;
521 struct sock *sknode;
522 unsigned int h;
523
524 for (h = 0; h < PN_HASHSIZE; h++) {
525 sk_for_each_rcu(sknode, hlist) {
526 if (!net_eq(net, sock_net(sknode)))
527 continue;
528 if (!pos)
529 return sknode;
530 pos--;
531 }
532 hlist++;
533 }
534 return NULL;
535 }
536
pn_sock_get_next(struct seq_file * seq,struct sock * sk)537 static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk)
538 {
539 struct net *net = seq_file_net(seq);
540
541 do
542 sk = sk_next(sk);
543 while (sk && !net_eq(net, sock_net(sk)));
544
545 return sk;
546 }
547
pn_sock_seq_start(struct seq_file * seq,loff_t * pos)548 static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)
549 __acquires(rcu)
550 {
551 rcu_read_lock();
552 return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
553 }
554
pn_sock_seq_next(struct seq_file * seq,void * v,loff_t * pos)555 static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos)
556 {
557 struct sock *sk;
558
559 if (v == SEQ_START_TOKEN)
560 sk = pn_sock_get_idx(seq, 0);
561 else
562 sk = pn_sock_get_next(seq, v);
563 (*pos)++;
564 return sk;
565 }
566
pn_sock_seq_stop(struct seq_file * seq,void * v)567 static void pn_sock_seq_stop(struct seq_file *seq, void *v)
568 __releases(rcu)
569 {
570 rcu_read_unlock();
571 }
572
pn_sock_seq_show(struct seq_file * seq,void * v)573 static int pn_sock_seq_show(struct seq_file *seq, void *v)
574 {
575 seq_setwidth(seq, 127);
576 if (v == SEQ_START_TOKEN)
577 seq_puts(seq, "pt loc rem rs st tx_queue rx_queue "
578 " uid inode ref pointer drops");
579 else {
580 struct sock *sk = v;
581 struct pn_sock *pn = pn_sk(sk);
582
583 seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu "
584 "%d %pK %u",
585 sk->sk_protocol, pn->sobject, pn->dobject,
586 pn->resource, sk->sk_state,
587 sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk),
588 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
589 sock_i_ino(sk),
590 refcount_read(&sk->sk_refcnt), sk,
591 atomic_read(&sk->sk_drops));
592 }
593 seq_pad(seq, '\n');
594 return 0;
595 }
596
597 const struct seq_operations pn_sock_seq_ops = {
598 .start = pn_sock_seq_start,
599 .next = pn_sock_seq_next,
600 .stop = pn_sock_seq_stop,
601 .show = pn_sock_seq_show,
602 };
603 #endif
604
605 static struct {
606 struct sock *sk[256];
607 } pnres;
608
609 /*
610 * Find and hold socket based on resource.
611 */
pn_find_sock_by_res(struct net * net,u8 res)612 struct sock *pn_find_sock_by_res(struct net *net, u8 res)
613 {
614 struct sock *sk;
615
616 if (!net_eq(net, &init_net))
617 return NULL;
618
619 rcu_read_lock();
620 sk = rcu_dereference(pnres.sk[res]);
621 if (sk)
622 sock_hold(sk);
623 rcu_read_unlock();
624 return sk;
625 }
626
627 static DEFINE_MUTEX(resource_mutex);
628
pn_sock_bind_res(struct sock * sk,u8 res)629 int pn_sock_bind_res(struct sock *sk, u8 res)
630 {
631 int ret = -EADDRINUSE;
632
633 if (!net_eq(sock_net(sk), &init_net))
634 return -ENOIOCTLCMD;
635 if (!capable(CAP_SYS_ADMIN))
636 return -EPERM;
637 if (pn_socket_autobind(sk->sk_socket))
638 return -EAGAIN;
639
640 mutex_lock(&resource_mutex);
641 if (pnres.sk[res] == NULL) {
642 sock_hold(sk);
643 rcu_assign_pointer(pnres.sk[res], sk);
644 ret = 0;
645 }
646 mutex_unlock(&resource_mutex);
647 return ret;
648 }
649
pn_sock_unbind_res(struct sock * sk,u8 res)650 int pn_sock_unbind_res(struct sock *sk, u8 res)
651 {
652 int ret = -ENOENT;
653
654 if (!capable(CAP_SYS_ADMIN))
655 return -EPERM;
656
657 mutex_lock(&resource_mutex);
658 if (pnres.sk[res] == sk) {
659 RCU_INIT_POINTER(pnres.sk[res], NULL);
660 ret = 0;
661 }
662 mutex_unlock(&resource_mutex);
663
664 if (ret == 0) {
665 synchronize_rcu();
666 sock_put(sk);
667 }
668 return ret;
669 }
670
pn_sock_unbind_all_res(struct sock * sk)671 void pn_sock_unbind_all_res(struct sock *sk)
672 {
673 unsigned int res, match = 0;
674
675 mutex_lock(&resource_mutex);
676 for (res = 0; res < 256; res++) {
677 if (pnres.sk[res] == sk) {
678 RCU_INIT_POINTER(pnres.sk[res], NULL);
679 match++;
680 }
681 }
682 mutex_unlock(&resource_mutex);
683
684 while (match > 0) {
685 __sock_put(sk);
686 match--;
687 }
688 /* Caller is responsible for RCU sync before final sock_put() */
689 }
690
691 #ifdef CONFIG_PROC_FS
pn_res_get_idx(struct seq_file * seq,loff_t pos)692 static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos)
693 {
694 struct net *net = seq_file_net(seq);
695 unsigned int i;
696
697 if (!net_eq(net, &init_net))
698 return NULL;
699
700 for (i = 0; i < 256; i++) {
701 if (pnres.sk[i] == NULL)
702 continue;
703 if (!pos)
704 return pnres.sk + i;
705 pos--;
706 }
707 return NULL;
708 }
709
pn_res_get_next(struct seq_file * seq,struct sock ** sk)710 static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk)
711 {
712 struct net *net = seq_file_net(seq);
713 unsigned int i;
714
715 BUG_ON(!net_eq(net, &init_net));
716
717 for (i = (sk - pnres.sk) + 1; i < 256; i++)
718 if (pnres.sk[i])
719 return pnres.sk + i;
720 return NULL;
721 }
722
pn_res_seq_start(struct seq_file * seq,loff_t * pos)723 static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos)
724 __acquires(resource_mutex)
725 {
726 mutex_lock(&resource_mutex);
727 return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
728 }
729
pn_res_seq_next(struct seq_file * seq,void * v,loff_t * pos)730 static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos)
731 {
732 struct sock **sk;
733
734 if (v == SEQ_START_TOKEN)
735 sk = pn_res_get_idx(seq, 0);
736 else
737 sk = pn_res_get_next(seq, v);
738 (*pos)++;
739 return sk;
740 }
741
pn_res_seq_stop(struct seq_file * seq,void * v)742 static void pn_res_seq_stop(struct seq_file *seq, void *v)
743 __releases(resource_mutex)
744 {
745 mutex_unlock(&resource_mutex);
746 }
747
pn_res_seq_show(struct seq_file * seq,void * v)748 static int pn_res_seq_show(struct seq_file *seq, void *v)
749 {
750 seq_setwidth(seq, 63);
751 if (v == SEQ_START_TOKEN)
752 seq_puts(seq, "rs uid inode");
753 else {
754 struct sock **psk = v;
755 struct sock *sk = *psk;
756
757 seq_printf(seq, "%02X %5u %lu",
758 (int) (psk - pnres.sk),
759 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
760 sock_i_ino(sk));
761 }
762 seq_pad(seq, '\n');
763 return 0;
764 }
765
766 const struct seq_operations pn_res_seq_ops = {
767 .start = pn_res_seq_start,
768 .next = pn_res_seq_next,
769 .stop = pn_res_seq_stop,
770 .show = pn_res_seq_show,
771 };
772 #endif
773