1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2011  Intel Corporation. All rights reserved.
4 */
5
6#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
7
8#include <linux/init.h>
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/nfc.h>
12#include <linux/sched/signal.h>
13
14#include "nfc.h"
15#include "llcp.h"
16
17static int sock_wait_state(struct sock *sk, int state, unsigned long timeo)
18{
19	DECLARE_WAITQUEUE(wait, current);
20	int err = 0;
21
22	pr_debug("sk %p", sk);
23
24	add_wait_queue(sk_sleep(sk), &wait);
25	set_current_state(TASK_INTERRUPTIBLE);
26
27	while (sk->sk_state != state) {
28		if (!timeo) {
29			err = -EINPROGRESS;
30			break;
31		}
32
33		if (signal_pending(current)) {
34			err = sock_intr_errno(timeo);
35			break;
36		}
37
38		release_sock(sk);
39		timeo = schedule_timeout(timeo);
40		lock_sock(sk);
41		set_current_state(TASK_INTERRUPTIBLE);
42
43		err = sock_error(sk);
44		if (err)
45			break;
46	}
47
48	__set_current_state(TASK_RUNNING);
49	remove_wait_queue(sk_sleep(sk), &wait);
50	return err;
51}
52
53static struct proto llcp_sock_proto = {
54	.name     = "NFC_LLCP",
55	.owner    = THIS_MODULE,
56	.obj_size = sizeof(struct nfc_llcp_sock),
57};
58
59static int llcp_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
60{
61	struct sock *sk = sock->sk;
62	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
63	struct nfc_llcp_local *local;
64	struct nfc_dev *dev;
65	struct sockaddr_nfc_llcp llcp_addr;
66	int len, ret = 0;
67
68	if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
69	    addr->sa_family != AF_NFC)
70		return -EINVAL;
71
72	pr_debug("sk %p addr %p family %d\n", sk, addr, addr->sa_family);
73
74	memset(&llcp_addr, 0, sizeof(llcp_addr));
75	len = min_t(unsigned int, sizeof(llcp_addr), alen);
76	memcpy(&llcp_addr, addr, len);
77
78	/* This is going to be a listening socket, dsap must be 0 */
79	if (llcp_addr.dsap != 0)
80		return -EINVAL;
81
82	lock_sock(sk);
83
84	if (sk->sk_state != LLCP_CLOSED) {
85		ret = -EBADFD;
86		goto error;
87	}
88
89	dev = nfc_get_device(llcp_addr.dev_idx);
90	if (dev == NULL) {
91		ret = -ENODEV;
92		goto error;
93	}
94
95	local = nfc_llcp_find_local(dev);
96	if (local == NULL) {
97		ret = -ENODEV;
98		goto put_dev;
99	}
100
101	llcp_sock->dev = dev;
102	llcp_sock->local = local;
103	llcp_sock->nfc_protocol = llcp_addr.nfc_protocol;
104	llcp_sock->service_name_len = min_t(unsigned int,
105					    llcp_addr.service_name_len,
106					    NFC_LLCP_MAX_SERVICE_NAME);
107	llcp_sock->service_name = kmemdup(llcp_addr.service_name,
108					  llcp_sock->service_name_len,
109					  GFP_KERNEL);
110	if (!llcp_sock->service_name) {
111		ret = -ENOMEM;
112		goto sock_llcp_put_local;
113	}
114	llcp_sock->ssap = nfc_llcp_get_sdp_ssap(local, llcp_sock);
115	if (llcp_sock->ssap == LLCP_SAP_MAX) {
116		ret = -EADDRINUSE;
117		goto free_service_name;
118	}
119
120	llcp_sock->reserved_ssap = llcp_sock->ssap;
121
122	nfc_llcp_sock_link(&local->sockets, sk);
123
124	pr_debug("Socket bound to SAP %d\n", llcp_sock->ssap);
125
126	sk->sk_state = LLCP_BOUND;
127	nfc_put_device(dev);
128	release_sock(sk);
129
130	return 0;
131
132free_service_name:
133	kfree(llcp_sock->service_name);
134	llcp_sock->service_name = NULL;
135
136sock_llcp_put_local:
137	nfc_llcp_local_put(llcp_sock->local);
138	llcp_sock->local = NULL;
139	llcp_sock->dev = NULL;
140
141put_dev:
142	nfc_put_device(dev);
143
144error:
145	release_sock(sk);
146	return ret;
147}
148
149static int llcp_raw_sock_bind(struct socket *sock, struct sockaddr *addr,
150			      int alen)
151{
152	struct sock *sk = sock->sk;
153	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
154	struct nfc_llcp_local *local;
155	struct nfc_dev *dev;
156	struct sockaddr_nfc_llcp llcp_addr;
157	int len, ret = 0;
158
159	if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
160	    addr->sa_family != AF_NFC)
161		return -EINVAL;
162
163	pr_debug("sk %p addr %p family %d\n", sk, addr, addr->sa_family);
164
165	memset(&llcp_addr, 0, sizeof(llcp_addr));
166	len = min_t(unsigned int, sizeof(llcp_addr), alen);
167	memcpy(&llcp_addr, addr, len);
168
169	lock_sock(sk);
170
171	if (sk->sk_state != LLCP_CLOSED) {
172		ret = -EBADFD;
173		goto error;
174	}
175
176	dev = nfc_get_device(llcp_addr.dev_idx);
177	if (dev == NULL) {
178		ret = -ENODEV;
179		goto error;
180	}
181
182	local = nfc_llcp_find_local(dev);
183	if (local == NULL) {
184		ret = -ENODEV;
185		goto put_dev;
186	}
187
188	llcp_sock->dev = dev;
189	llcp_sock->local = local;
190	llcp_sock->nfc_protocol = llcp_addr.nfc_protocol;
191
192	nfc_llcp_sock_link(&local->raw_sockets, sk);
193
194	sk->sk_state = LLCP_BOUND;
195
196put_dev:
197	nfc_put_device(dev);
198
199error:
200	release_sock(sk);
201	return ret;
202}
203
204static int llcp_sock_listen(struct socket *sock, int backlog)
205{
206	struct sock *sk = sock->sk;
207	int ret = 0;
208
209	pr_debug("sk %p backlog %d\n", sk, backlog);
210
211	lock_sock(sk);
212
213	if ((sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM) ||
214	    sk->sk_state != LLCP_BOUND) {
215		ret = -EBADFD;
216		goto error;
217	}
218
219	sk->sk_max_ack_backlog = backlog;
220	sk->sk_ack_backlog = 0;
221
222	pr_debug("Socket listening\n");
223	sk->sk_state = LLCP_LISTEN;
224
225error:
226	release_sock(sk);
227
228	return ret;
229}
230
231static int nfc_llcp_setsockopt(struct socket *sock, int level, int optname,
232			       sockptr_t optval, unsigned int optlen)
233{
234	struct sock *sk = sock->sk;
235	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
236	u32 opt;
237	int err = 0;
238
239	pr_debug("%p optname %d\n", sk, optname);
240
241	if (level != SOL_NFC)
242		return -ENOPROTOOPT;
243
244	lock_sock(sk);
245
246	switch (optname) {
247	case NFC_LLCP_RW:
248		if (sk->sk_state == LLCP_CONNECTED ||
249		    sk->sk_state == LLCP_BOUND ||
250		    sk->sk_state == LLCP_LISTEN) {
251			err = -EINVAL;
252			break;
253		}
254
255		err = copy_safe_from_sockptr(&opt, sizeof(opt),
256					     optval, optlen);
257		if (err)
258			break;
259
260		if (opt > LLCP_MAX_RW) {
261			err = -EINVAL;
262			break;
263		}
264
265		llcp_sock->rw = (u8) opt;
266
267		break;
268
269	case NFC_LLCP_MIUX:
270		if (sk->sk_state == LLCP_CONNECTED ||
271		    sk->sk_state == LLCP_BOUND ||
272		    sk->sk_state == LLCP_LISTEN) {
273			err = -EINVAL;
274			break;
275		}
276
277		err = copy_safe_from_sockptr(&opt, sizeof(opt),
278					     optval, optlen);
279		if (err)
280			break;
281
282		if (opt > LLCP_MAX_MIUX) {
283			err = -EINVAL;
284			break;
285		}
286
287		llcp_sock->miux = cpu_to_be16((u16) opt);
288
289		break;
290
291	default:
292		err = -ENOPROTOOPT;
293		break;
294	}
295
296	release_sock(sk);
297
298	pr_debug("%p rw %d miux %d\n", llcp_sock,
299		 llcp_sock->rw, llcp_sock->miux);
300
301	return err;
302}
303
304static int nfc_llcp_getsockopt(struct socket *sock, int level, int optname,
305			       char __user *optval, int __user *optlen)
306{
307	struct nfc_llcp_local *local;
308	struct sock *sk = sock->sk;
309	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
310	int len, err = 0;
311	u16 miux, remote_miu;
312	u8 rw;
313
314	pr_debug("%p optname %d\n", sk, optname);
315
316	if (level != SOL_NFC)
317		return -ENOPROTOOPT;
318
319	if (get_user(len, optlen))
320		return -EFAULT;
321
322	local = llcp_sock->local;
323	if (!local)
324		return -ENODEV;
325
326	len = min_t(u32, len, sizeof(u32));
327
328	lock_sock(sk);
329
330	switch (optname) {
331	case NFC_LLCP_RW:
332		rw = llcp_sock->rw > LLCP_MAX_RW ? local->rw : llcp_sock->rw;
333		if (put_user(rw, (u32 __user *) optval))
334			err = -EFAULT;
335
336		break;
337
338	case NFC_LLCP_MIUX:
339		miux = be16_to_cpu(llcp_sock->miux) > LLCP_MAX_MIUX ?
340			be16_to_cpu(local->miux) : be16_to_cpu(llcp_sock->miux);
341
342		if (put_user(miux, (u32 __user *) optval))
343			err = -EFAULT;
344
345		break;
346
347	case NFC_LLCP_REMOTE_MIU:
348		remote_miu = llcp_sock->remote_miu > LLCP_MAX_MIU ?
349				local->remote_miu : llcp_sock->remote_miu;
350
351		if (put_user(remote_miu, (u32 __user *) optval))
352			err = -EFAULT;
353
354		break;
355
356	case NFC_LLCP_REMOTE_LTO:
357		if (put_user(local->remote_lto / 10, (u32 __user *) optval))
358			err = -EFAULT;
359
360		break;
361
362	case NFC_LLCP_REMOTE_RW:
363		if (put_user(llcp_sock->remote_rw, (u32 __user *) optval))
364			err = -EFAULT;
365
366		break;
367
368	default:
369		err = -ENOPROTOOPT;
370		break;
371	}
372
373	release_sock(sk);
374
375	if (put_user(len, optlen))
376		return -EFAULT;
377
378	return err;
379}
380
381void nfc_llcp_accept_unlink(struct sock *sk)
382{
383	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
384
385	pr_debug("state %d\n", sk->sk_state);
386
387	list_del_init(&llcp_sock->accept_queue);
388	sk_acceptq_removed(llcp_sock->parent);
389	llcp_sock->parent = NULL;
390
391	sock_put(sk);
392}
393
394void nfc_llcp_accept_enqueue(struct sock *parent, struct sock *sk)
395{
396	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
397	struct nfc_llcp_sock *llcp_sock_parent = nfc_llcp_sock(parent);
398
399	/* Lock will be free from unlink */
400	sock_hold(sk);
401
402	list_add_tail(&llcp_sock->accept_queue,
403		      &llcp_sock_parent->accept_queue);
404	llcp_sock->parent = parent;
405	sk_acceptq_added(parent);
406}
407
408struct sock *nfc_llcp_accept_dequeue(struct sock *parent,
409				     struct socket *newsock)
410{
411	struct nfc_llcp_sock *lsk, *n, *llcp_parent;
412	struct sock *sk;
413
414	llcp_parent = nfc_llcp_sock(parent);
415
416	list_for_each_entry_safe(lsk, n, &llcp_parent->accept_queue,
417				 accept_queue) {
418		sk = &lsk->sk;
419		lock_sock(sk);
420
421		if (sk->sk_state == LLCP_CLOSED) {
422			release_sock(sk);
423			nfc_llcp_accept_unlink(sk);
424			continue;
425		}
426
427		if (sk->sk_state == LLCP_CONNECTED || !newsock) {
428			list_del_init(&lsk->accept_queue);
429			sock_put(sk);
430
431			if (newsock)
432				sock_graft(sk, newsock);
433
434			release_sock(sk);
435
436			pr_debug("Returning sk state %d\n", sk->sk_state);
437
438			sk_acceptq_removed(parent);
439
440			return sk;
441		}
442
443		release_sock(sk);
444	}
445
446	return NULL;
447}
448
449static int llcp_sock_accept(struct socket *sock, struct socket *newsock,
450			    int flags, bool kern)
451{
452	DECLARE_WAITQUEUE(wait, current);
453	struct sock *sk = sock->sk, *new_sk;
454	long timeo;
455	int ret = 0;
456
457	pr_debug("parent %p\n", sk);
458
459	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
460
461	if (sk->sk_state != LLCP_LISTEN) {
462		ret = -EBADFD;
463		goto error;
464	}
465
466	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
467
468	/* Wait for an incoming connection. */
469	add_wait_queue_exclusive(sk_sleep(sk), &wait);
470	while (!(new_sk = nfc_llcp_accept_dequeue(sk, newsock))) {
471		set_current_state(TASK_INTERRUPTIBLE);
472
473		if (!timeo) {
474			ret = -EAGAIN;
475			break;
476		}
477
478		if (signal_pending(current)) {
479			ret = sock_intr_errno(timeo);
480			break;
481		}
482
483		release_sock(sk);
484		timeo = schedule_timeout(timeo);
485		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
486	}
487	__set_current_state(TASK_RUNNING);
488	remove_wait_queue(sk_sleep(sk), &wait);
489
490	if (ret)
491		goto error;
492
493	newsock->state = SS_CONNECTED;
494
495	pr_debug("new socket %p\n", new_sk);
496
497error:
498	release_sock(sk);
499
500	return ret;
501}
502
503static int llcp_sock_getname(struct socket *sock, struct sockaddr *uaddr,
504			     int peer)
505{
506	struct sock *sk = sock->sk;
507	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
508	DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, llcp_addr, uaddr);
509
510	if (llcp_sock == NULL || llcp_sock->dev == NULL)
511		return -EBADFD;
512
513	pr_debug("%p %d %d %d\n", sk, llcp_sock->target_idx,
514		 llcp_sock->dsap, llcp_sock->ssap);
515
516	memset(llcp_addr, 0, sizeof(*llcp_addr));
517
518	lock_sock(sk);
519	if (!llcp_sock->dev) {
520		release_sock(sk);
521		return -EBADFD;
522	}
523	llcp_addr->sa_family = AF_NFC;
524	llcp_addr->dev_idx = llcp_sock->dev->idx;
525	llcp_addr->target_idx = llcp_sock->target_idx;
526	llcp_addr->nfc_protocol = llcp_sock->nfc_protocol;
527	llcp_addr->dsap = llcp_sock->dsap;
528	llcp_addr->ssap = llcp_sock->ssap;
529	llcp_addr->service_name_len = llcp_sock->service_name_len;
530	memcpy(llcp_addr->service_name, llcp_sock->service_name,
531	       llcp_addr->service_name_len);
532	release_sock(sk);
533
534	return sizeof(struct sockaddr_nfc_llcp);
535}
536
537static inline __poll_t llcp_accept_poll(struct sock *parent)
538{
539	struct nfc_llcp_sock *llcp_sock, *parent_sock;
540	struct sock *sk;
541
542	parent_sock = nfc_llcp_sock(parent);
543
544	list_for_each_entry(llcp_sock, &parent_sock->accept_queue,
545			    accept_queue) {
546		sk = &llcp_sock->sk;
547
548		if (sk->sk_state == LLCP_CONNECTED)
549			return EPOLLIN | EPOLLRDNORM;
550	}
551
552	return 0;
553}
554
555static __poll_t llcp_sock_poll(struct file *file, struct socket *sock,
556				   poll_table *wait)
557{
558	struct sock *sk = sock->sk;
559	__poll_t mask = 0;
560
561	pr_debug("%p\n", sk);
562
563	sock_poll_wait(file, sock, wait);
564
565	if (sk->sk_state == LLCP_LISTEN)
566		return llcp_accept_poll(sk);
567
568	if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
569		mask |= EPOLLERR |
570			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
571
572	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
573		mask |= EPOLLIN | EPOLLRDNORM;
574
575	if (sk->sk_state == LLCP_CLOSED)
576		mask |= EPOLLHUP;
577
578	if (sk->sk_shutdown & RCV_SHUTDOWN)
579		mask |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
580
581	if (sk->sk_shutdown == SHUTDOWN_MASK)
582		mask |= EPOLLHUP;
583
584	if (sock_writeable(sk) && sk->sk_state == LLCP_CONNECTED)
585		mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
586	else
587		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
588
589	pr_debug("mask 0x%x\n", mask);
590
591	return mask;
592}
593
594static int llcp_sock_release(struct socket *sock)
595{
596	struct sock *sk = sock->sk;
597	struct nfc_llcp_local *local;
598	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
599	int err = 0;
600
601	if (!sk)
602		return 0;
603
604	pr_debug("%p\n", sk);
605
606	local = llcp_sock->local;
607	if (local == NULL) {
608		err = -ENODEV;
609		goto out;
610	}
611
612	lock_sock(sk);
613
614	/* Send a DISC */
615	if (sk->sk_state == LLCP_CONNECTED)
616		nfc_llcp_send_disconnect(llcp_sock);
617
618	if (sk->sk_state == LLCP_LISTEN) {
619		struct nfc_llcp_sock *lsk, *n;
620		struct sock *accept_sk;
621
622		list_for_each_entry_safe(lsk, n, &llcp_sock->accept_queue,
623					 accept_queue) {
624			accept_sk = &lsk->sk;
625			lock_sock(accept_sk);
626
627			nfc_llcp_send_disconnect(lsk);
628			nfc_llcp_accept_unlink(accept_sk);
629
630			release_sock(accept_sk);
631		}
632	}
633
634	if (sock->type == SOCK_RAW)
635		nfc_llcp_sock_unlink(&local->raw_sockets, sk);
636	else
637		nfc_llcp_sock_unlink(&local->sockets, sk);
638
639	if (llcp_sock->reserved_ssap < LLCP_SAP_MAX)
640		nfc_llcp_put_ssap(llcp_sock->local, llcp_sock->ssap);
641
642	release_sock(sk);
643
644out:
645	sock_orphan(sk);
646	sock_put(sk);
647
648	return err;
649}
650
651static int llcp_sock_connect(struct socket *sock, struct sockaddr *_addr,
652			     int len, int flags)
653{
654	struct sock *sk = sock->sk;
655	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
656	struct sockaddr_nfc_llcp *addr = (struct sockaddr_nfc_llcp *)_addr;
657	struct nfc_dev *dev;
658	struct nfc_llcp_local *local;
659	int ret = 0;
660
661	pr_debug("sock %p sk %p flags 0x%x\n", sock, sk, flags);
662
663	if (!addr || len < sizeof(*addr) || addr->sa_family != AF_NFC)
664		return -EINVAL;
665
666	if (addr->service_name_len == 0 && addr->dsap == 0)
667		return -EINVAL;
668
669	pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", addr->dev_idx,
670		 addr->target_idx, addr->nfc_protocol);
671
672	lock_sock(sk);
673
674	if (sk->sk_state == LLCP_CONNECTED) {
675		ret = -EISCONN;
676		goto error;
677	}
678	if (sk->sk_state == LLCP_CONNECTING) {
679		ret = -EINPROGRESS;
680		goto error;
681	}
682
683	dev = nfc_get_device(addr->dev_idx);
684	if (dev == NULL) {
685		ret = -ENODEV;
686		goto error;
687	}
688
689	local = nfc_llcp_find_local(dev);
690	if (local == NULL) {
691		ret = -ENODEV;
692		goto put_dev;
693	}
694
695	device_lock(&dev->dev);
696	if (dev->dep_link_up == false) {
697		ret = -ENOLINK;
698		device_unlock(&dev->dev);
699		goto sock_llcp_put_local;
700	}
701	device_unlock(&dev->dev);
702
703	if (local->rf_mode == NFC_RF_INITIATOR &&
704	    addr->target_idx != local->target_idx) {
705		ret = -ENOLINK;
706		goto sock_llcp_put_local;
707	}
708
709	llcp_sock->dev = dev;
710	llcp_sock->local = local;
711	llcp_sock->ssap = nfc_llcp_get_local_ssap(local);
712	if (llcp_sock->ssap == LLCP_SAP_MAX) {
713		ret = -ENOMEM;
714		goto sock_llcp_nullify;
715	}
716
717	llcp_sock->reserved_ssap = llcp_sock->ssap;
718
719	if (addr->service_name_len == 0)
720		llcp_sock->dsap = addr->dsap;
721	else
722		llcp_sock->dsap = LLCP_SAP_SDP;
723	llcp_sock->nfc_protocol = addr->nfc_protocol;
724	llcp_sock->service_name_len = min_t(unsigned int,
725					    addr->service_name_len,
726					    NFC_LLCP_MAX_SERVICE_NAME);
727	llcp_sock->service_name = kmemdup(addr->service_name,
728					  llcp_sock->service_name_len,
729					  GFP_KERNEL);
730	if (!llcp_sock->service_name) {
731		ret = -ENOMEM;
732		goto sock_llcp_release;
733	}
734
735	nfc_llcp_sock_link(&local->connecting_sockets, sk);
736
737	ret = nfc_llcp_send_connect(llcp_sock);
738	if (ret)
739		goto sock_unlink;
740
741	sk->sk_state = LLCP_CONNECTING;
742
743	ret = sock_wait_state(sk, LLCP_CONNECTED,
744			      sock_sndtimeo(sk, flags & O_NONBLOCK));
745	if (ret && ret != -EINPROGRESS)
746		goto sock_unlink;
747
748	release_sock(sk);
749
750	return ret;
751
752sock_unlink:
753	nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
754	kfree(llcp_sock->service_name);
755	llcp_sock->service_name = NULL;
756
757sock_llcp_release:
758	nfc_llcp_put_ssap(local, llcp_sock->ssap);
759
760sock_llcp_nullify:
761	llcp_sock->local = NULL;
762	llcp_sock->dev = NULL;
763
764sock_llcp_put_local:
765	nfc_llcp_local_put(local);
766
767put_dev:
768	nfc_put_device(dev);
769
770error:
771	release_sock(sk);
772	return ret;
773}
774
775static int llcp_sock_sendmsg(struct socket *sock, struct msghdr *msg,
776			     size_t len)
777{
778	struct sock *sk = sock->sk;
779	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
780	int ret;
781
782	pr_debug("sock %p sk %p", sock, sk);
783
784	ret = sock_error(sk);
785	if (ret)
786		return ret;
787
788	if (msg->msg_flags & MSG_OOB)
789		return -EOPNOTSUPP;
790
791	lock_sock(sk);
792
793	if (!llcp_sock->local) {
794		release_sock(sk);
795		return -ENODEV;
796	}
797
798	if (sk->sk_type == SOCK_DGRAM) {
799		if (sk->sk_state != LLCP_BOUND) {
800			release_sock(sk);
801			return -ENOTCONN;
802		}
803
804		DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, addr,
805				 msg->msg_name);
806
807		if (msg->msg_namelen < sizeof(*addr)) {
808			release_sock(sk);
809			return -EINVAL;
810		}
811
812		release_sock(sk);
813
814		return nfc_llcp_send_ui_frame(llcp_sock, addr->dsap, addr->ssap,
815					      msg, len);
816	}
817
818	if (sk->sk_state != LLCP_CONNECTED) {
819		release_sock(sk);
820		return -ENOTCONN;
821	}
822
823	release_sock(sk);
824
825	return nfc_llcp_send_i_frame(llcp_sock, msg, len);
826}
827
828static int llcp_sock_recvmsg(struct socket *sock, struct msghdr *msg,
829			     size_t len, int flags)
830{
831	struct sock *sk = sock->sk;
832	unsigned int copied, rlen;
833	struct sk_buff *skb, *cskb;
834	int err = 0;
835
836	pr_debug("%p %zu\n", sk, len);
837
838	lock_sock(sk);
839
840	if (sk->sk_state == LLCP_CLOSED &&
841	    skb_queue_empty(&sk->sk_receive_queue)) {
842		release_sock(sk);
843		return 0;
844	}
845
846	release_sock(sk);
847
848	if (flags & (MSG_OOB))
849		return -EOPNOTSUPP;
850
851	skb = skb_recv_datagram(sk, flags, &err);
852	if (!skb) {
853		pr_err("Recv datagram failed state %d %d %d",
854		       sk->sk_state, err, sock_error(sk));
855
856		if (sk->sk_shutdown & RCV_SHUTDOWN)
857			return 0;
858
859		return err;
860	}
861
862	rlen = skb->len;		/* real length of skb */
863	copied = min_t(unsigned int, rlen, len);
864
865	cskb = skb;
866	if (skb_copy_datagram_msg(cskb, 0, msg, copied)) {
867		if (!(flags & MSG_PEEK))
868			skb_queue_head(&sk->sk_receive_queue, skb);
869		return -EFAULT;
870	}
871
872	sock_recv_timestamp(msg, sk, skb);
873
874	if (sk->sk_type == SOCK_DGRAM && msg->msg_name) {
875		struct nfc_llcp_ui_cb *ui_cb = nfc_llcp_ui_skb_cb(skb);
876		DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, sockaddr,
877				 msg->msg_name);
878
879		msg->msg_namelen = sizeof(struct sockaddr_nfc_llcp);
880
881		pr_debug("Datagram socket %d %d\n", ui_cb->dsap, ui_cb->ssap);
882
883		memset(sockaddr, 0, sizeof(*sockaddr));
884		sockaddr->sa_family = AF_NFC;
885		sockaddr->nfc_protocol = NFC_PROTO_NFC_DEP;
886		sockaddr->dsap = ui_cb->dsap;
887		sockaddr->ssap = ui_cb->ssap;
888	}
889
890	/* Mark read part of skb as used */
891	if (!(flags & MSG_PEEK)) {
892
893		/* SOCK_STREAM: re-queue skb if it contains unreceived data */
894		if (sk->sk_type == SOCK_STREAM ||
895		    sk->sk_type == SOCK_DGRAM ||
896		    sk->sk_type == SOCK_RAW) {
897			skb_pull(skb, copied);
898			if (skb->len) {
899				skb_queue_head(&sk->sk_receive_queue, skb);
900				goto done;
901			}
902		}
903
904		kfree_skb(skb);
905	}
906
907	/* XXX Queue backlogged skbs */
908
909done:
910	/* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
911	if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
912		copied = rlen;
913
914	return copied;
915}
916
917static const struct proto_ops llcp_sock_ops = {
918	.family         = PF_NFC,
919	.owner          = THIS_MODULE,
920	.bind           = llcp_sock_bind,
921	.connect        = llcp_sock_connect,
922	.release        = llcp_sock_release,
923	.socketpair     = sock_no_socketpair,
924	.accept         = llcp_sock_accept,
925	.getname        = llcp_sock_getname,
926	.poll           = llcp_sock_poll,
927	.ioctl          = sock_no_ioctl,
928	.listen         = llcp_sock_listen,
929	.shutdown       = sock_no_shutdown,
930	.setsockopt     = nfc_llcp_setsockopt,
931	.getsockopt     = nfc_llcp_getsockopt,
932	.sendmsg        = llcp_sock_sendmsg,
933	.recvmsg        = llcp_sock_recvmsg,
934	.mmap           = sock_no_mmap,
935};
936
937static const struct proto_ops llcp_rawsock_ops = {
938	.family         = PF_NFC,
939	.owner          = THIS_MODULE,
940	.bind           = llcp_raw_sock_bind,
941	.connect        = sock_no_connect,
942	.release        = llcp_sock_release,
943	.socketpair     = sock_no_socketpair,
944	.accept         = sock_no_accept,
945	.getname        = llcp_sock_getname,
946	.poll           = llcp_sock_poll,
947	.ioctl          = sock_no_ioctl,
948	.listen         = sock_no_listen,
949	.shutdown       = sock_no_shutdown,
950	.sendmsg        = sock_no_sendmsg,
951	.recvmsg        = llcp_sock_recvmsg,
952	.mmap           = sock_no_mmap,
953};
954
955static void llcp_sock_destruct(struct sock *sk)
956{
957	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
958
959	pr_debug("%p\n", sk);
960
961	if (sk->sk_state == LLCP_CONNECTED)
962		nfc_put_device(llcp_sock->dev);
963
964	skb_queue_purge(&sk->sk_receive_queue);
965
966	nfc_llcp_sock_free(llcp_sock);
967
968	if (!sock_flag(sk, SOCK_DEAD)) {
969		pr_err("Freeing alive NFC LLCP socket %p\n", sk);
970		return;
971	}
972}
973
974struct sock *nfc_llcp_sock_alloc(struct socket *sock, int type, gfp_t gfp, int kern)
975{
976	struct sock *sk;
977	struct nfc_llcp_sock *llcp_sock;
978
979	sk = sk_alloc(&init_net, PF_NFC, gfp, &llcp_sock_proto, kern);
980	if (!sk)
981		return NULL;
982
983	llcp_sock = nfc_llcp_sock(sk);
984
985	sock_init_data(sock, sk);
986	sk->sk_state = LLCP_CLOSED;
987	sk->sk_protocol = NFC_SOCKPROTO_LLCP;
988	sk->sk_type = type;
989	sk->sk_destruct = llcp_sock_destruct;
990
991	llcp_sock->ssap = 0;
992	llcp_sock->dsap = LLCP_SAP_SDP;
993	llcp_sock->rw = LLCP_MAX_RW + 1;
994	llcp_sock->miux = cpu_to_be16(LLCP_MAX_MIUX + 1);
995	llcp_sock->send_n = llcp_sock->send_ack_n = 0;
996	llcp_sock->recv_n = llcp_sock->recv_ack_n = 0;
997	llcp_sock->remote_ready = 1;
998	llcp_sock->reserved_ssap = LLCP_SAP_MAX;
999	nfc_llcp_socket_remote_param_init(llcp_sock);
1000	skb_queue_head_init(&llcp_sock->tx_queue);
1001	skb_queue_head_init(&llcp_sock->tx_pending_queue);
1002	INIT_LIST_HEAD(&llcp_sock->accept_queue);
1003
1004	if (sock != NULL)
1005		sock->state = SS_UNCONNECTED;
1006
1007	return sk;
1008}
1009
1010void nfc_llcp_sock_free(struct nfc_llcp_sock *sock)
1011{
1012	kfree(sock->service_name);
1013
1014	skb_queue_purge(&sock->tx_queue);
1015	skb_queue_purge(&sock->tx_pending_queue);
1016
1017	list_del_init(&sock->accept_queue);
1018
1019	sock->parent = NULL;
1020
1021	nfc_llcp_local_put(sock->local);
1022}
1023
1024static int llcp_sock_create(struct net *net, struct socket *sock,
1025			    const struct nfc_protocol *nfc_proto, int kern)
1026{
1027	struct sock *sk;
1028
1029	pr_debug("%p\n", sock);
1030
1031	if (sock->type != SOCK_STREAM &&
1032	    sock->type != SOCK_DGRAM &&
1033	    sock->type != SOCK_RAW)
1034		return -ESOCKTNOSUPPORT;
1035
1036	if (sock->type == SOCK_RAW) {
1037		if (!capable(CAP_NET_RAW))
1038			return -EPERM;
1039		sock->ops = &llcp_rawsock_ops;
1040	} else {
1041		sock->ops = &llcp_sock_ops;
1042	}
1043
1044	sk = nfc_llcp_sock_alloc(sock, sock->type, GFP_ATOMIC, kern);
1045	if (sk == NULL)
1046		return -ENOMEM;
1047
1048	return 0;
1049}
1050
1051static const struct nfc_protocol llcp_nfc_proto = {
1052	.id	  = NFC_SOCKPROTO_LLCP,
1053	.proto    = &llcp_sock_proto,
1054	.owner    = THIS_MODULE,
1055	.create   = llcp_sock_create
1056};
1057
1058int __init nfc_llcp_sock_init(void)
1059{
1060	return nfc_proto_register(&llcp_nfc_proto);
1061}
1062
1063void nfc_llcp_sock_exit(void)
1064{
1065	nfc_proto_unregister(&llcp_nfc_proto);
1066}
1067