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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
28static 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
43static struct {
44 struct hlist_head hlist[PN_HASHSIZE];
45 struct mutex lock;
46} pnsocks;
47
48void __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
57static 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 */
66struct 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) */
104void 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
132int 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}
142EXPORT_SYMBOL(pn_sock_hash);
143
144void 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}
152EXPORT_SYMBOL(pn_sock_unhash);
153
154static DEFINE_MUTEX(port_mutex);
155
156static 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);
195out_port:
196 mutex_unlock(&port_mutex);
197out:
198 release_sock(sk);
199 return err;
200}
201
202static 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
217static 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;
289out:
290 release_sock(sk);
291 return err;
292}
293
294static 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
315static 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
330static __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
356static 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 if (dev)
383 dev_put(dev);
384 if (saddr == PN_NO_ADDR)
385 return -EHOSTUNREACH;
386
387 handle = pn_object(saddr, pn_port(pn->sobject));
388 return put_user(handle, (__u16 __user *)arg);
389 }
390
391 return sk->sk_prot->ioctl(sk, cmd, arg);
392}
393
394static int pn_socket_listen(struct socket *sock, int backlog)
395{
396 struct sock *sk = sock->sk;
397 int err = 0;
398
399 if (pn_socket_autobind(sock))
400 return -ENOBUFS;
401
402 lock_sock(sk);
403 if (sock->state != SS_UNCONNECTED) {
404 err = -EINVAL;
405 goto out;
406 }
407
408 if (sk->sk_state != TCP_LISTEN) {
409 sk->sk_state = TCP_LISTEN;
410 sk->sk_ack_backlog = 0;
411 }
412 sk->sk_max_ack_backlog = backlog;
413out:
414 release_sock(sk);
415 return err;
416}
417
418static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m,
419 size_t total_len)
420{
421 struct sock *sk = sock->sk;
422
423 if (pn_socket_autobind(sock))
424 return -EAGAIN;
425
426 return sk->sk_prot->sendmsg(sk, m, total_len);
427}
428
429const struct proto_ops phonet_dgram_ops = {
430 .family = AF_PHONET,
431 .owner = THIS_MODULE,
432 .release = pn_socket_release,
433 .bind = pn_socket_bind,
434 .connect = sock_no_connect,
435 .socketpair = sock_no_socketpair,
436 .accept = sock_no_accept,
437 .getname = pn_socket_getname,
438 .poll = datagram_poll,
439 .ioctl = pn_socket_ioctl,
440 .listen = sock_no_listen,
441 .shutdown = sock_no_shutdown,
442 .sendmsg = pn_socket_sendmsg,
443 .recvmsg = sock_common_recvmsg,
444 .mmap = sock_no_mmap,
445 .sendpage = sock_no_sendpage,
446};
447
448const struct proto_ops phonet_stream_ops = {
449 .family = AF_PHONET,
450 .owner = THIS_MODULE,
451 .release = pn_socket_release,
452 .bind = pn_socket_bind,
453 .connect = pn_socket_connect,
454 .socketpair = sock_no_socketpair,
455 .accept = pn_socket_accept,
456 .getname = pn_socket_getname,
457 .poll = pn_socket_poll,
458 .ioctl = pn_socket_ioctl,
459 .listen = pn_socket_listen,
460 .shutdown = sock_no_shutdown,
461 .setsockopt = sock_common_setsockopt,
462 .getsockopt = sock_common_getsockopt,
463 .sendmsg = pn_socket_sendmsg,
464 .recvmsg = sock_common_recvmsg,
465 .mmap = sock_no_mmap,
466 .sendpage = sock_no_sendpage,
467};
468EXPORT_SYMBOL(phonet_stream_ops);
469
470/* allocate port for a socket */
471int pn_sock_get_port(struct sock *sk, unsigned short sport)
472{
473 static int port_cur;
474 struct net *net = sock_net(sk);
475 struct pn_sock *pn = pn_sk(sk);
476 struct sockaddr_pn try_sa;
477 struct sock *tmpsk;
478
479 memset(&try_sa, 0, sizeof(struct sockaddr_pn));
480 try_sa.spn_family = AF_PHONET;
481 WARN_ON(!mutex_is_locked(&port_mutex));
482 if (!sport) {
483 /* search free port */
484 int port, pmin, pmax;
485
486 phonet_get_local_port_range(&pmin, &pmax);
487 for (port = pmin; port <= pmax; port++) {
488 port_cur++;
489 if (port_cur < pmin || port_cur > pmax)
490 port_cur = pmin;
491
492 pn_sockaddr_set_port(&try_sa, port_cur);
493 tmpsk = pn_find_sock_by_sa(net, &try_sa);
494 if (tmpsk == NULL) {
495 sport = port_cur;
496 goto found;
497 } else
498 sock_put(tmpsk);
499 }
500 } else {
501 /* try to find specific port */
502 pn_sockaddr_set_port(&try_sa, sport);
503 tmpsk = pn_find_sock_by_sa(net, &try_sa);
504 if (tmpsk == NULL)
505 /* No sock there! We can use that port... */
506 goto found;
507 else
508 sock_put(tmpsk);
509 }
510 /* the port must be in use already */
511 return -EADDRINUSE;
512
513found:
514 pn->sobject = pn_object(pn_addr(pn->sobject), sport);
515 return 0;
516}
517EXPORT_SYMBOL(pn_sock_get_port);
518
519#ifdef CONFIG_PROC_FS
520static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos)
521{
522 struct net *net = seq_file_net(seq);
523 struct hlist_head *hlist = pnsocks.hlist;
524 struct sock *sknode;
525 unsigned int h;
526
527 for (h = 0; h < PN_HASHSIZE; h++) {
528 sk_for_each_rcu(sknode, hlist) {
529 if (!net_eq(net, sock_net(sknode)))
530 continue;
531 if (!pos)
532 return sknode;
533 pos--;
534 }
535 hlist++;
536 }
537 return NULL;
538}
539
540static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk)
541{
542 struct net *net = seq_file_net(seq);
543
544 do
545 sk = sk_next(sk);
546 while (sk && !net_eq(net, sock_net(sk)));
547
548 return sk;
549}
550
551static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)
552 __acquires(rcu)
553{
554 rcu_read_lock();
555 return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
556}
557
558static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos)
559{
560 struct sock *sk;
561
562 if (v == SEQ_START_TOKEN)
563 sk = pn_sock_get_idx(seq, 0);
564 else
565 sk = pn_sock_get_next(seq, v);
566 (*pos)++;
567 return sk;
568}
569
570static void pn_sock_seq_stop(struct seq_file *seq, void *v)
571 __releases(rcu)
572{
573 rcu_read_unlock();
574}
575
576static int pn_sock_seq_show(struct seq_file *seq, void *v)
577{
578 seq_setwidth(seq, 127);
579 if (v == SEQ_START_TOKEN)
580 seq_puts(seq, "pt loc rem rs st tx_queue rx_queue "
581 " uid inode ref pointer drops");
582 else {
583 struct sock *sk = v;
584 struct pn_sock *pn = pn_sk(sk);
585
586 seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu "
587 "%d %pK %u",
588 sk->sk_protocol, pn->sobject, pn->dobject,
589 pn->resource, sk->sk_state,
590 sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk),
591 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
592 sock_i_ino(sk),
593 refcount_read(&sk->sk_refcnt), sk,
594 atomic_read(&sk->sk_drops));
595 }
596 seq_pad(seq, '\n');
597 return 0;
598}
599
600const struct seq_operations pn_sock_seq_ops = {
601 .start = pn_sock_seq_start,
602 .next = pn_sock_seq_next,
603 .stop = pn_sock_seq_stop,
604 .show = pn_sock_seq_show,
605};
606#endif
607
608static struct {
609 struct sock *sk[256];
610} pnres;
611
612/*
613 * Find and hold socket based on resource.
614 */
615struct sock *pn_find_sock_by_res(struct net *net, u8 res)
616{
617 struct sock *sk;
618
619 if (!net_eq(net, &init_net))
620 return NULL;
621
622 rcu_read_lock();
623 sk = rcu_dereference(pnres.sk[res]);
624 if (sk)
625 sock_hold(sk);
626 rcu_read_unlock();
627 return sk;
628}
629
630static DEFINE_MUTEX(resource_mutex);
631
632int pn_sock_bind_res(struct sock *sk, u8 res)
633{
634 int ret = -EADDRINUSE;
635
636 if (!net_eq(sock_net(sk), &init_net))
637 return -ENOIOCTLCMD;
638 if (!capable(CAP_SYS_ADMIN))
639 return -EPERM;
640 if (pn_socket_autobind(sk->sk_socket))
641 return -EAGAIN;
642
643 mutex_lock(&resource_mutex);
644 if (pnres.sk[res] == NULL) {
645 sock_hold(sk);
646 rcu_assign_pointer(pnres.sk[res], sk);
647 ret = 0;
648 }
649 mutex_unlock(&resource_mutex);
650 return ret;
651}
652
653int pn_sock_unbind_res(struct sock *sk, u8 res)
654{
655 int ret = -ENOENT;
656
657 if (!capable(CAP_SYS_ADMIN))
658 return -EPERM;
659
660 mutex_lock(&resource_mutex);
661 if (pnres.sk[res] == sk) {
662 RCU_INIT_POINTER(pnres.sk[res], NULL);
663 ret = 0;
664 }
665 mutex_unlock(&resource_mutex);
666
667 if (ret == 0) {
668 synchronize_rcu();
669 sock_put(sk);
670 }
671 return ret;
672}
673
674void pn_sock_unbind_all_res(struct sock *sk)
675{
676 unsigned int res, match = 0;
677
678 mutex_lock(&resource_mutex);
679 for (res = 0; res < 256; res++) {
680 if (pnres.sk[res] == sk) {
681 RCU_INIT_POINTER(pnres.sk[res], NULL);
682 match++;
683 }
684 }
685 mutex_unlock(&resource_mutex);
686
687 while (match > 0) {
688 __sock_put(sk);
689 match--;
690 }
691 /* Caller is responsible for RCU sync before final sock_put() */
692}
693
694#ifdef CONFIG_PROC_FS
695static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos)
696{
697 struct net *net = seq_file_net(seq);
698 unsigned int i;
699
700 if (!net_eq(net, &init_net))
701 return NULL;
702
703 for (i = 0; i < 256; i++) {
704 if (pnres.sk[i] == NULL)
705 continue;
706 if (!pos)
707 return pnres.sk + i;
708 pos--;
709 }
710 return NULL;
711}
712
713static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk)
714{
715 struct net *net = seq_file_net(seq);
716 unsigned int i;
717
718 BUG_ON(!net_eq(net, &init_net));
719
720 for (i = (sk - pnres.sk) + 1; i < 256; i++)
721 if (pnres.sk[i])
722 return pnres.sk + i;
723 return NULL;
724}
725
726static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos)
727 __acquires(resource_mutex)
728{
729 mutex_lock(&resource_mutex);
730 return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
731}
732
733static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos)
734{
735 struct sock **sk;
736
737 if (v == SEQ_START_TOKEN)
738 sk = pn_res_get_idx(seq, 0);
739 else
740 sk = pn_res_get_next(seq, v);
741 (*pos)++;
742 return sk;
743}
744
745static void pn_res_seq_stop(struct seq_file *seq, void *v)
746 __releases(resource_mutex)
747{
748 mutex_unlock(&resource_mutex);
749}
750
751static int pn_res_seq_show(struct seq_file *seq, void *v)
752{
753 seq_setwidth(seq, 63);
754 if (v == SEQ_START_TOKEN)
755 seq_puts(seq, "rs uid inode");
756 else {
757 struct sock **psk = v;
758 struct sock *sk = *psk;
759
760 seq_printf(seq, "%02X %5u %lu",
761 (int) (psk - pnres.sk),
762 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
763 sock_i_ino(sk));
764 }
765 seq_pad(seq, '\n');
766 return 0;
767}
768
769const struct seq_operations pn_res_seq_ops = {
770 .start = pn_res_seq_start,
771 .next = pn_res_seq_next,
772 .stop = pn_res_seq_stop,
773 .show = pn_res_seq_show,
774};
775#endif
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
28static 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
43static struct {
44 struct hlist_head hlist[PN_HASHSIZE];
45 struct mutex lock;
46} pnsocks;
47
48void __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
57static 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 */
66struct 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) */
104void 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
132int 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}
142EXPORT_SYMBOL(pn_sock_hash);
143
144void 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}
152EXPORT_SYMBOL(pn_sock_unhash);
153
154static DEFINE_MUTEX(port_mutex);
155
156static 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);
195out_port:
196 mutex_unlock(&port_mutex);
197out:
198 release_sock(sk);
199 return err;
200}
201
202static 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
217static 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;
289out:
290 release_sock(sk);
291 return err;
292}
293
294static int pn_socket_accept(struct socket *sock, struct socket *newsock,
295 struct proto_accept_arg *arg)
296{
297 struct sock *sk = sock->sk;
298 struct sock *newsk;
299
300 if (unlikely(sk->sk_state != TCP_LISTEN))
301 return -EINVAL;
302
303 newsk = sk->sk_prot->accept(sk, arg);
304 if (!newsk)
305 return arg->err;
306
307 lock_sock(newsk);
308 sock_graft(newsk, newsock);
309 newsock->state = SS_CONNECTED;
310 release_sock(newsk);
311 return 0;
312}
313
314static int pn_socket_getname(struct socket *sock, struct sockaddr *addr,
315 int peer)
316{
317 struct sock *sk = sock->sk;
318 struct pn_sock *pn = pn_sk(sk);
319
320 memset(addr, 0, sizeof(struct sockaddr_pn));
321 addr->sa_family = AF_PHONET;
322 if (!peer) /* Race with bind() here is userland's problem. */
323 pn_sockaddr_set_object((struct sockaddr_pn *)addr,
324 pn->sobject);
325
326 return sizeof(struct sockaddr_pn);
327}
328
329static __poll_t pn_socket_poll(struct file *file, struct socket *sock,
330 poll_table *wait)
331{
332 struct sock *sk = sock->sk;
333 struct pep_sock *pn = pep_sk(sk);
334 __poll_t mask = 0;
335
336 poll_wait(file, sk_sleep(sk), wait);
337
338 if (sk->sk_state == TCP_CLOSE)
339 return EPOLLERR;
340 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
341 mask |= EPOLLIN | EPOLLRDNORM;
342 if (!skb_queue_empty_lockless(&pn->ctrlreq_queue))
343 mask |= EPOLLPRI;
344 if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
345 return EPOLLHUP;
346
347 if (sk->sk_state == TCP_ESTABLISHED &&
348 refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf &&
349 atomic_read(&pn->tx_credits))
350 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
351
352 return mask;
353}
354
355static int pn_socket_ioctl(struct socket *sock, unsigned int cmd,
356 unsigned long arg)
357{
358 struct sock *sk = sock->sk;
359 struct pn_sock *pn = pn_sk(sk);
360
361 if (cmd == SIOCPNGETOBJECT) {
362 struct net_device *dev;
363 u16 handle;
364 u8 saddr;
365
366 if (get_user(handle, (__u16 __user *)arg))
367 return -EFAULT;
368
369 lock_sock(sk);
370 if (sk->sk_bound_dev_if)
371 dev = dev_get_by_index(sock_net(sk),
372 sk->sk_bound_dev_if);
373 else
374 dev = phonet_device_get(sock_net(sk));
375 if (dev && (dev->flags & IFF_UP))
376 saddr = phonet_address_get(dev, pn_addr(handle));
377 else
378 saddr = PN_NO_ADDR;
379 release_sock(sk);
380
381 dev_put(dev);
382 if (saddr == PN_NO_ADDR)
383 return -EHOSTUNREACH;
384
385 handle = pn_object(saddr, pn_port(pn->sobject));
386 return put_user(handle, (__u16 __user *)arg);
387 }
388
389 return sk_ioctl(sk, cmd, (void __user *)arg);
390}
391
392static int pn_socket_listen(struct socket *sock, int backlog)
393{
394 struct sock *sk = sock->sk;
395 int err = 0;
396
397 if (pn_socket_autobind(sock))
398 return -ENOBUFS;
399
400 lock_sock(sk);
401 if (sock->state != SS_UNCONNECTED) {
402 err = -EINVAL;
403 goto out;
404 }
405
406 if (sk->sk_state != TCP_LISTEN) {
407 sk->sk_state = TCP_LISTEN;
408 sk->sk_ack_backlog = 0;
409 }
410 sk->sk_max_ack_backlog = backlog;
411out:
412 release_sock(sk);
413 return err;
414}
415
416static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m,
417 size_t total_len)
418{
419 struct sock *sk = sock->sk;
420
421 if (pn_socket_autobind(sock))
422 return -EAGAIN;
423
424 return sk->sk_prot->sendmsg(sk, m, total_len);
425}
426
427const struct proto_ops phonet_dgram_ops = {
428 .family = AF_PHONET,
429 .owner = THIS_MODULE,
430 .release = pn_socket_release,
431 .bind = pn_socket_bind,
432 .connect = sock_no_connect,
433 .socketpair = sock_no_socketpair,
434 .accept = sock_no_accept,
435 .getname = pn_socket_getname,
436 .poll = datagram_poll,
437 .ioctl = pn_socket_ioctl,
438 .listen = sock_no_listen,
439 .shutdown = sock_no_shutdown,
440 .sendmsg = pn_socket_sendmsg,
441 .recvmsg = sock_common_recvmsg,
442 .mmap = sock_no_mmap,
443};
444
445const struct proto_ops phonet_stream_ops = {
446 .family = AF_PHONET,
447 .owner = THIS_MODULE,
448 .release = pn_socket_release,
449 .bind = pn_socket_bind,
450 .connect = pn_socket_connect,
451 .socketpair = sock_no_socketpair,
452 .accept = pn_socket_accept,
453 .getname = pn_socket_getname,
454 .poll = pn_socket_poll,
455 .ioctl = pn_socket_ioctl,
456 .listen = pn_socket_listen,
457 .shutdown = sock_no_shutdown,
458 .setsockopt = sock_common_setsockopt,
459 .getsockopt = sock_common_getsockopt,
460 .sendmsg = pn_socket_sendmsg,
461 .recvmsg = sock_common_recvmsg,
462 .mmap = sock_no_mmap,
463};
464EXPORT_SYMBOL(phonet_stream_ops);
465
466/* allocate port for a socket */
467int pn_sock_get_port(struct sock *sk, unsigned short sport)
468{
469 static int port_cur;
470 struct net *net = sock_net(sk);
471 struct pn_sock *pn = pn_sk(sk);
472 struct sockaddr_pn try_sa;
473 struct sock *tmpsk;
474
475 memset(&try_sa, 0, sizeof(struct sockaddr_pn));
476 try_sa.spn_family = AF_PHONET;
477 WARN_ON(!mutex_is_locked(&port_mutex));
478 if (!sport) {
479 /* search free port */
480 int port, pmin, pmax;
481
482 phonet_get_local_port_range(&pmin, &pmax);
483 for (port = pmin; port <= pmax; port++) {
484 port_cur++;
485 if (port_cur < pmin || port_cur > pmax)
486 port_cur = pmin;
487
488 pn_sockaddr_set_port(&try_sa, port_cur);
489 tmpsk = pn_find_sock_by_sa(net, &try_sa);
490 if (tmpsk == NULL) {
491 sport = port_cur;
492 goto found;
493 } else
494 sock_put(tmpsk);
495 }
496 } else {
497 /* try to find specific port */
498 pn_sockaddr_set_port(&try_sa, sport);
499 tmpsk = pn_find_sock_by_sa(net, &try_sa);
500 if (tmpsk == NULL)
501 /* No sock there! We can use that port... */
502 goto found;
503 else
504 sock_put(tmpsk);
505 }
506 /* the port must be in use already */
507 return -EADDRINUSE;
508
509found:
510 pn->sobject = pn_object(pn_addr(pn->sobject), sport);
511 return 0;
512}
513EXPORT_SYMBOL(pn_sock_get_port);
514
515#ifdef CONFIG_PROC_FS
516static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos)
517{
518 struct net *net = seq_file_net(seq);
519 struct hlist_head *hlist = pnsocks.hlist;
520 struct sock *sknode;
521 unsigned int h;
522
523 for (h = 0; h < PN_HASHSIZE; h++) {
524 sk_for_each_rcu(sknode, hlist) {
525 if (!net_eq(net, sock_net(sknode)))
526 continue;
527 if (!pos)
528 return sknode;
529 pos--;
530 }
531 hlist++;
532 }
533 return NULL;
534}
535
536static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk)
537{
538 struct net *net = seq_file_net(seq);
539
540 do
541 sk = sk_next(sk);
542 while (sk && !net_eq(net, sock_net(sk)));
543
544 return sk;
545}
546
547static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)
548 __acquires(rcu)
549{
550 rcu_read_lock();
551 return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
552}
553
554static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos)
555{
556 struct sock *sk;
557
558 if (v == SEQ_START_TOKEN)
559 sk = pn_sock_get_idx(seq, 0);
560 else
561 sk = pn_sock_get_next(seq, v);
562 (*pos)++;
563 return sk;
564}
565
566static void pn_sock_seq_stop(struct seq_file *seq, void *v)
567 __releases(rcu)
568{
569 rcu_read_unlock();
570}
571
572static int pn_sock_seq_show(struct seq_file *seq, void *v)
573{
574 seq_setwidth(seq, 127);
575 if (v == SEQ_START_TOKEN)
576 seq_puts(seq, "pt loc rem rs st tx_queue rx_queue "
577 " uid inode ref pointer drops");
578 else {
579 struct sock *sk = v;
580 struct pn_sock *pn = pn_sk(sk);
581
582 seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu "
583 "%d %pK %u",
584 sk->sk_protocol, pn->sobject, pn->dobject,
585 pn->resource, sk->sk_state,
586 sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk),
587 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
588 sock_i_ino(sk),
589 refcount_read(&sk->sk_refcnt), sk,
590 atomic_read(&sk->sk_drops));
591 }
592 seq_pad(seq, '\n');
593 return 0;
594}
595
596const struct seq_operations pn_sock_seq_ops = {
597 .start = pn_sock_seq_start,
598 .next = pn_sock_seq_next,
599 .stop = pn_sock_seq_stop,
600 .show = pn_sock_seq_show,
601};
602#endif
603
604static struct {
605 struct sock *sk[256];
606} pnres;
607
608/*
609 * Find and hold socket based on resource.
610 */
611struct sock *pn_find_sock_by_res(struct net *net, u8 res)
612{
613 struct sock *sk;
614
615 if (!net_eq(net, &init_net))
616 return NULL;
617
618 rcu_read_lock();
619 sk = rcu_dereference(pnres.sk[res]);
620 if (sk)
621 sock_hold(sk);
622 rcu_read_unlock();
623 return sk;
624}
625
626static DEFINE_MUTEX(resource_mutex);
627
628int pn_sock_bind_res(struct sock *sk, u8 res)
629{
630 int ret = -EADDRINUSE;
631
632 if (!net_eq(sock_net(sk), &init_net))
633 return -ENOIOCTLCMD;
634 if (!capable(CAP_SYS_ADMIN))
635 return -EPERM;
636 if (pn_socket_autobind(sk->sk_socket))
637 return -EAGAIN;
638
639 mutex_lock(&resource_mutex);
640 if (pnres.sk[res] == NULL) {
641 sock_hold(sk);
642 rcu_assign_pointer(pnres.sk[res], sk);
643 ret = 0;
644 }
645 mutex_unlock(&resource_mutex);
646 return ret;
647}
648
649int pn_sock_unbind_res(struct sock *sk, u8 res)
650{
651 int ret = -ENOENT;
652
653 if (!capable(CAP_SYS_ADMIN))
654 return -EPERM;
655
656 mutex_lock(&resource_mutex);
657 if (pnres.sk[res] == sk) {
658 RCU_INIT_POINTER(pnres.sk[res], NULL);
659 ret = 0;
660 }
661 mutex_unlock(&resource_mutex);
662
663 if (ret == 0) {
664 synchronize_rcu();
665 sock_put(sk);
666 }
667 return ret;
668}
669
670void pn_sock_unbind_all_res(struct sock *sk)
671{
672 unsigned int res, match = 0;
673
674 mutex_lock(&resource_mutex);
675 for (res = 0; res < 256; res++) {
676 if (pnres.sk[res] == sk) {
677 RCU_INIT_POINTER(pnres.sk[res], NULL);
678 match++;
679 }
680 }
681 mutex_unlock(&resource_mutex);
682
683 while (match > 0) {
684 __sock_put(sk);
685 match--;
686 }
687 /* Caller is responsible for RCU sync before final sock_put() */
688}
689
690#ifdef CONFIG_PROC_FS
691static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos)
692{
693 struct net *net = seq_file_net(seq);
694 unsigned int i;
695
696 if (!net_eq(net, &init_net))
697 return NULL;
698
699 for (i = 0; i < 256; i++) {
700 if (pnres.sk[i] == NULL)
701 continue;
702 if (!pos)
703 return pnres.sk + i;
704 pos--;
705 }
706 return NULL;
707}
708
709static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk)
710{
711 struct net *net = seq_file_net(seq);
712 unsigned int i;
713
714 BUG_ON(!net_eq(net, &init_net));
715
716 for (i = (sk - pnres.sk) + 1; i < 256; i++)
717 if (pnres.sk[i])
718 return pnres.sk + i;
719 return NULL;
720}
721
722static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos)
723 __acquires(resource_mutex)
724{
725 mutex_lock(&resource_mutex);
726 return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
727}
728
729static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos)
730{
731 struct sock **sk;
732
733 if (v == SEQ_START_TOKEN)
734 sk = pn_res_get_idx(seq, 0);
735 else
736 sk = pn_res_get_next(seq, v);
737 (*pos)++;
738 return sk;
739}
740
741static void pn_res_seq_stop(struct seq_file *seq, void *v)
742 __releases(resource_mutex)
743{
744 mutex_unlock(&resource_mutex);
745}
746
747static int pn_res_seq_show(struct seq_file *seq, void *v)
748{
749 seq_setwidth(seq, 63);
750 if (v == SEQ_START_TOKEN)
751 seq_puts(seq, "rs uid inode");
752 else {
753 struct sock **psk = v;
754 struct sock *sk = *psk;
755
756 seq_printf(seq, "%02X %5u %lu",
757 (int) (psk - pnres.sk),
758 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
759 sock_i_ino(sk));
760 }
761 seq_pad(seq, '\n');
762 return 0;
763}
764
765const struct seq_operations pn_res_seq_ops = {
766 .start = pn_res_seq_start,
767 .next = pn_res_seq_next,
768 .stop = pn_res_seq_stop,
769 .show = pn_res_seq_show,
770};
771#endif