1/*
2 * Copyright (C) 2011  Intel Corporation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
16 */
17
18#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
19
20#include <linux/init.h>
21#include <linux/kernel.h>
22#include <linux/list.h>
23#include <linux/nfc.h>
24
25#include "nfc.h"
26#include "llcp.h"
27
28static u8 llcp_magic[3] = {0x46, 0x66, 0x6d};
29
30static LIST_HEAD(llcp_devices);
31
32static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb);
33
34void nfc_llcp_sock_link(struct llcp_sock_list *l, struct sock *sk)
35{
36	write_lock(&l->lock);
37	sk_add_node(sk, &l->head);
38	write_unlock(&l->lock);
39}
40
41void nfc_llcp_sock_unlink(struct llcp_sock_list *l, struct sock *sk)
42{
43	write_lock(&l->lock);
44	sk_del_node_init(sk);
45	write_unlock(&l->lock);
46}
47
48void nfc_llcp_socket_remote_param_init(struct nfc_llcp_sock *sock)
49{
50	sock->remote_rw = LLCP_DEFAULT_RW;
51	sock->remote_miu = LLCP_MAX_MIU + 1;
52}
53
54static void nfc_llcp_socket_purge(struct nfc_llcp_sock *sock)
55{
56	struct nfc_llcp_local *local = sock->local;
57	struct sk_buff *s, *tmp;
58
59	pr_debug("%p\n", &sock->sk);
60
61	skb_queue_purge(&sock->tx_queue);
62	skb_queue_purge(&sock->tx_pending_queue);
63
64	if (local == NULL)
65		return;
66
67	/* Search for local pending SKBs that are related to this socket */
68	skb_queue_walk_safe(&local->tx_queue, s, tmp) {
69		if (s->sk != &sock->sk)
70			continue;
71
72		skb_unlink(s, &local->tx_queue);
73		kfree_skb(s);
74	}
75}
76
77static void nfc_llcp_socket_release(struct nfc_llcp_local *local, bool device,
78				    int err)
79{
80	struct sock *sk;
81	struct hlist_node *tmp;
82	struct nfc_llcp_sock *llcp_sock;
83
84	skb_queue_purge(&local->tx_queue);
85
86	write_lock(&local->sockets.lock);
87
88	sk_for_each_safe(sk, tmp, &local->sockets.head) {
89		llcp_sock = nfc_llcp_sock(sk);
90
91		bh_lock_sock(sk);
92
93		nfc_llcp_socket_purge(llcp_sock);
94
95		if (sk->sk_state == LLCP_CONNECTED)
96			nfc_put_device(llcp_sock->dev);
97
98		if (sk->sk_state == LLCP_LISTEN) {
99			struct nfc_llcp_sock *lsk, *n;
100			struct sock *accept_sk;
101
102			list_for_each_entry_safe(lsk, n,
103						 &llcp_sock->accept_queue,
104						 accept_queue) {
105				accept_sk = &lsk->sk;
106				bh_lock_sock(accept_sk);
107
108				nfc_llcp_accept_unlink(accept_sk);
109
110				if (err)
111					accept_sk->sk_err = err;
112				accept_sk->sk_state = LLCP_CLOSED;
113				accept_sk->sk_state_change(sk);
114
115				bh_unlock_sock(accept_sk);
116			}
117		}
118
119		if (err)
120			sk->sk_err = err;
121		sk->sk_state = LLCP_CLOSED;
122		sk->sk_state_change(sk);
123
124		bh_unlock_sock(sk);
125
126		sk_del_node_init(sk);
127	}
128
129	write_unlock(&local->sockets.lock);
130
131	/* If we still have a device, we keep the RAW sockets alive */
132	if (device == true)
133		return;
134
135	write_lock(&local->raw_sockets.lock);
136
137	sk_for_each_safe(sk, tmp, &local->raw_sockets.head) {
138		llcp_sock = nfc_llcp_sock(sk);
139
140		bh_lock_sock(sk);
141
142		nfc_llcp_socket_purge(llcp_sock);
143
144		if (err)
145			sk->sk_err = err;
146		sk->sk_state = LLCP_CLOSED;
147		sk->sk_state_change(sk);
148
149		bh_unlock_sock(sk);
150
151		sk_del_node_init(sk);
152	}
153
154	write_unlock(&local->raw_sockets.lock);
155}
156
157struct nfc_llcp_local *nfc_llcp_local_get(struct nfc_llcp_local *local)
158{
159	kref_get(&local->ref);
160
161	return local;
162}
163
164static void local_cleanup(struct nfc_llcp_local *local)
165{
166	nfc_llcp_socket_release(local, false, ENXIO);
167	del_timer_sync(&local->link_timer);
168	skb_queue_purge(&local->tx_queue);
169	cancel_work_sync(&local->tx_work);
170	cancel_work_sync(&local->rx_work);
171	cancel_work_sync(&local->timeout_work);
172	kfree_skb(local->rx_pending);
173	del_timer_sync(&local->sdreq_timer);
174	cancel_work_sync(&local->sdreq_timeout_work);
175	nfc_llcp_free_sdp_tlv_list(&local->pending_sdreqs);
176}
177
178static void local_release(struct kref *ref)
179{
180	struct nfc_llcp_local *local;
181
182	local = container_of(ref, struct nfc_llcp_local, ref);
183
184	list_del(&local->list);
185	local_cleanup(local);
186	kfree(local);
187}
188
189int nfc_llcp_local_put(struct nfc_llcp_local *local)
190{
191	if (local == NULL)
192		return 0;
193
194	return kref_put(&local->ref, local_release);
195}
196
197static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
198					       u8 ssap, u8 dsap)
199{
200	struct sock *sk;
201	struct nfc_llcp_sock *llcp_sock, *tmp_sock;
202
203	pr_debug("ssap dsap %d %d\n", ssap, dsap);
204
205	if (ssap == 0 && dsap == 0)
206		return NULL;
207
208	read_lock(&local->sockets.lock);
209
210	llcp_sock = NULL;
211
212	sk_for_each(sk, &local->sockets.head) {
213		tmp_sock = nfc_llcp_sock(sk);
214
215		if (tmp_sock->ssap == ssap && tmp_sock->dsap == dsap) {
216			llcp_sock = tmp_sock;
217			break;
218		}
219	}
220
221	read_unlock(&local->sockets.lock);
222
223	if (llcp_sock == NULL)
224		return NULL;
225
226	sock_hold(&llcp_sock->sk);
227
228	return llcp_sock;
229}
230
231static void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
232{
233	sock_put(&sock->sk);
234}
235
236static void nfc_llcp_timeout_work(struct work_struct *work)
237{
238	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
239						    timeout_work);
240
241	nfc_dep_link_down(local->dev);
242}
243
244static void nfc_llcp_symm_timer(unsigned long data)
245{
246	struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
247
248	pr_err("SYMM timeout\n");
249
250	schedule_work(&local->timeout_work);
251}
252
253static void nfc_llcp_sdreq_timeout_work(struct work_struct *work)
254{
255	unsigned long time;
256	HLIST_HEAD(nl_sdres_list);
257	struct hlist_node *n;
258	struct nfc_llcp_sdp_tlv *sdp;
259	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
260						    sdreq_timeout_work);
261
262	mutex_lock(&local->sdreq_lock);
263
264	time = jiffies - msecs_to_jiffies(3 * local->remote_lto);
265
266	hlist_for_each_entry_safe(sdp, n, &local->pending_sdreqs, node) {
267		if (time_after(sdp->time, time))
268			continue;
269
270		sdp->sap = LLCP_SDP_UNBOUND;
271
272		hlist_del(&sdp->node);
273
274		hlist_add_head(&sdp->node, &nl_sdres_list);
275	}
276
277	if (!hlist_empty(&local->pending_sdreqs))
278		mod_timer(&local->sdreq_timer,
279			  jiffies + msecs_to_jiffies(3 * local->remote_lto));
280
281	mutex_unlock(&local->sdreq_lock);
282
283	if (!hlist_empty(&nl_sdres_list))
284		nfc_genl_llc_send_sdres(local->dev, &nl_sdres_list);
285}
286
287static void nfc_llcp_sdreq_timer(unsigned long data)
288{
289	struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
290
291	schedule_work(&local->sdreq_timeout_work);
292}
293
294struct nfc_llcp_local *nfc_llcp_find_local(struct nfc_dev *dev)
295{
296	struct nfc_llcp_local *local;
297
298	list_for_each_entry(local, &llcp_devices, list)
299		if (local->dev == dev)
300			return local;
301
302	pr_debug("No device found\n");
303
304	return NULL;
305}
306
307static char *wks[] = {
308	NULL,
309	NULL, /* SDP */
310	"urn:nfc:sn:ip",
311	"urn:nfc:sn:obex",
312	"urn:nfc:sn:snep",
313};
314
315static int nfc_llcp_wks_sap(char *service_name, size_t service_name_len)
316{
317	int sap, num_wks;
318
319	pr_debug("%s\n", service_name);
320
321	if (service_name == NULL)
322		return -EINVAL;
323
324	num_wks = ARRAY_SIZE(wks);
325
326	for (sap = 0; sap < num_wks; sap++) {
327		if (wks[sap] == NULL)
328			continue;
329
330		if (strncmp(wks[sap], service_name, service_name_len) == 0)
331			return sap;
332	}
333
334	return -EINVAL;
335}
336
337static
338struct nfc_llcp_sock *nfc_llcp_sock_from_sn(struct nfc_llcp_local *local,
339					    u8 *sn, size_t sn_len)
340{
341	struct sock *sk;
342	struct nfc_llcp_sock *llcp_sock, *tmp_sock;
343
344	pr_debug("sn %zd %p\n", sn_len, sn);
345
346	if (sn == NULL || sn_len == 0)
347		return NULL;
348
349	read_lock(&local->sockets.lock);
350
351	llcp_sock = NULL;
352
353	sk_for_each(sk, &local->sockets.head) {
354		tmp_sock = nfc_llcp_sock(sk);
355
356		pr_debug("llcp sock %p\n", tmp_sock);
357
358		if (tmp_sock->sk.sk_type == SOCK_STREAM &&
359		    tmp_sock->sk.sk_state != LLCP_LISTEN)
360			continue;
361
362		if (tmp_sock->sk.sk_type == SOCK_DGRAM &&
363		    tmp_sock->sk.sk_state != LLCP_BOUND)
364			continue;
365
366		if (tmp_sock->service_name == NULL ||
367		    tmp_sock->service_name_len == 0)
368			continue;
369
370		if (tmp_sock->service_name_len != sn_len)
371			continue;
372
373		if (memcmp(sn, tmp_sock->service_name, sn_len) == 0) {
374			llcp_sock = tmp_sock;
375			break;
376		}
377	}
378
379	read_unlock(&local->sockets.lock);
380
381	pr_debug("Found llcp sock %p\n", llcp_sock);
382
383	return llcp_sock;
384}
385
386u8 nfc_llcp_get_sdp_ssap(struct nfc_llcp_local *local,
387			 struct nfc_llcp_sock *sock)
388{
389	mutex_lock(&local->sdp_lock);
390
391	if (sock->service_name != NULL && sock->service_name_len > 0) {
392		int ssap = nfc_llcp_wks_sap(sock->service_name,
393					    sock->service_name_len);
394
395		if (ssap > 0) {
396			pr_debug("WKS %d\n", ssap);
397
398			/* This is a WKS, let's check if it's free */
399			if (local->local_wks & BIT(ssap)) {
400				mutex_unlock(&local->sdp_lock);
401
402				return LLCP_SAP_MAX;
403			}
404
405			set_bit(ssap, &local->local_wks);
406			mutex_unlock(&local->sdp_lock);
407
408			return ssap;
409		}
410
411		/*
412		 * Check if there already is a non WKS socket bound
413		 * to this service name.
414		 */
415		if (nfc_llcp_sock_from_sn(local, sock->service_name,
416					  sock->service_name_len) != NULL) {
417			mutex_unlock(&local->sdp_lock);
418
419			return LLCP_SAP_MAX;
420		}
421
422		mutex_unlock(&local->sdp_lock);
423
424		return LLCP_SDP_UNBOUND;
425
426	} else if (sock->ssap != 0 && sock->ssap < LLCP_WKS_NUM_SAP) {
427		if (!test_bit(sock->ssap, &local->local_wks)) {
428			set_bit(sock->ssap, &local->local_wks);
429			mutex_unlock(&local->sdp_lock);
430
431			return sock->ssap;
432		}
433	}
434
435	mutex_unlock(&local->sdp_lock);
436
437	return LLCP_SAP_MAX;
438}
439
440u8 nfc_llcp_get_local_ssap(struct nfc_llcp_local *local)
441{
442	u8 local_ssap;
443
444	mutex_lock(&local->sdp_lock);
445
446	local_ssap = find_first_zero_bit(&local->local_sap, LLCP_LOCAL_NUM_SAP);
447	if (local_ssap == LLCP_LOCAL_NUM_SAP) {
448		mutex_unlock(&local->sdp_lock);
449		return LLCP_SAP_MAX;
450	}
451
452	set_bit(local_ssap, &local->local_sap);
453
454	mutex_unlock(&local->sdp_lock);
455
456	return local_ssap + LLCP_LOCAL_SAP_OFFSET;
457}
458
459void nfc_llcp_put_ssap(struct nfc_llcp_local *local, u8 ssap)
460{
461	u8 local_ssap;
462	unsigned long *sdp;
463
464	if (ssap < LLCP_WKS_NUM_SAP) {
465		local_ssap = ssap;
466		sdp = &local->local_wks;
467	} else if (ssap < LLCP_LOCAL_NUM_SAP) {
468		atomic_t *client_cnt;
469
470		local_ssap = ssap - LLCP_WKS_NUM_SAP;
471		sdp = &local->local_sdp;
472		client_cnt = &local->local_sdp_cnt[local_ssap];
473
474		pr_debug("%d clients\n", atomic_read(client_cnt));
475
476		mutex_lock(&local->sdp_lock);
477
478		if (atomic_dec_and_test(client_cnt)) {
479			struct nfc_llcp_sock *l_sock;
480
481			pr_debug("No more clients for SAP %d\n", ssap);
482
483			clear_bit(local_ssap, sdp);
484
485			/* Find the listening sock and set it back to UNBOUND */
486			l_sock = nfc_llcp_sock_get(local, ssap, LLCP_SAP_SDP);
487			if (l_sock) {
488				l_sock->ssap = LLCP_SDP_UNBOUND;
489				nfc_llcp_sock_put(l_sock);
490			}
491		}
492
493		mutex_unlock(&local->sdp_lock);
494
495		return;
496	} else if (ssap < LLCP_MAX_SAP) {
497		local_ssap = ssap - LLCP_LOCAL_NUM_SAP;
498		sdp = &local->local_sap;
499	} else {
500		return;
501	}
502
503	mutex_lock(&local->sdp_lock);
504
505	clear_bit(local_ssap, sdp);
506
507	mutex_unlock(&local->sdp_lock);
508}
509
510static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
511{
512	u8 ssap;
513
514	mutex_lock(&local->sdp_lock);
515
516	ssap = find_first_zero_bit(&local->local_sdp, LLCP_SDP_NUM_SAP);
517	if (ssap == LLCP_SDP_NUM_SAP) {
518		mutex_unlock(&local->sdp_lock);
519
520		return LLCP_SAP_MAX;
521	}
522
523	pr_debug("SDP ssap %d\n", LLCP_WKS_NUM_SAP + ssap);
524
525	set_bit(ssap, &local->local_sdp);
526
527	mutex_unlock(&local->sdp_lock);
528
529	return LLCP_WKS_NUM_SAP + ssap;
530}
531
532static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
533{
534	u8 *gb_cur, *version_tlv, version, version_length;
535	u8 *lto_tlv, lto_length;
536	u8 *wks_tlv, wks_length;
537	u8 *miux_tlv, miux_length;
538	__be16 wks = cpu_to_be16(local->local_wks);
539	u8 gb_len = 0;
540	int ret = 0;
541
542	version = LLCP_VERSION_11;
543	version_tlv = nfc_llcp_build_tlv(LLCP_TLV_VERSION, &version,
544					 1, &version_length);
545	gb_len += version_length;
546
547	lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &local->lto, 1, &lto_length);
548	gb_len += lto_length;
549
550	pr_debug("Local wks 0x%lx\n", local->local_wks);
551	wks_tlv = nfc_llcp_build_tlv(LLCP_TLV_WKS, (u8 *)&wks, 2, &wks_length);
552	gb_len += wks_length;
553
554	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
555				      &miux_length);
556	gb_len += miux_length;
557
558	gb_len += ARRAY_SIZE(llcp_magic);
559
560	if (gb_len > NFC_MAX_GT_LEN) {
561		ret = -EINVAL;
562		goto out;
563	}
564
565	gb_cur = local->gb;
566
567	memcpy(gb_cur, llcp_magic, ARRAY_SIZE(llcp_magic));
568	gb_cur += ARRAY_SIZE(llcp_magic);
569
570	memcpy(gb_cur, version_tlv, version_length);
571	gb_cur += version_length;
572
573	memcpy(gb_cur, lto_tlv, lto_length);
574	gb_cur += lto_length;
575
576	memcpy(gb_cur, wks_tlv, wks_length);
577	gb_cur += wks_length;
578
579	memcpy(gb_cur, miux_tlv, miux_length);
580	gb_cur += miux_length;
581
582	local->gb_len = gb_len;
583
584out:
585	kfree(version_tlv);
586	kfree(lto_tlv);
587	kfree(wks_tlv);
588	kfree(miux_tlv);
589
590	return ret;
591}
592
593u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len)
594{
595	struct nfc_llcp_local *local;
596
597	local = nfc_llcp_find_local(dev);
598	if (local == NULL) {
599		*general_bytes_len = 0;
600		return NULL;
601	}
602
603	nfc_llcp_build_gb(local);
604
605	*general_bytes_len = local->gb_len;
606
607	return local->gb;
608}
609
610int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len)
611{
612	struct nfc_llcp_local *local;
613
614	if (gb_len < 3 || gb_len > NFC_MAX_GT_LEN)
615		return -EINVAL;
616
617	local = nfc_llcp_find_local(dev);
618	if (local == NULL) {
619		pr_err("No LLCP device\n");
620		return -ENODEV;
621	}
622
623	memset(local->remote_gb, 0, NFC_MAX_GT_LEN);
624	memcpy(local->remote_gb, gb, gb_len);
625	local->remote_gb_len = gb_len;
626
627	if (memcmp(local->remote_gb, llcp_magic, 3)) {
628		pr_err("MAC does not support LLCP\n");
629		return -EINVAL;
630	}
631
632	return nfc_llcp_parse_gb_tlv(local,
633				     &local->remote_gb[3],
634				     local->remote_gb_len - 3);
635}
636
637static u8 nfc_llcp_dsap(struct sk_buff *pdu)
638{
639	return (pdu->data[0] & 0xfc) >> 2;
640}
641
642static u8 nfc_llcp_ptype(struct sk_buff *pdu)
643{
644	return ((pdu->data[0] & 0x03) << 2) | ((pdu->data[1] & 0xc0) >> 6);
645}
646
647static u8 nfc_llcp_ssap(struct sk_buff *pdu)
648{
649	return pdu->data[1] & 0x3f;
650}
651
652static u8 nfc_llcp_ns(struct sk_buff *pdu)
653{
654	return pdu->data[2] >> 4;
655}
656
657static u8 nfc_llcp_nr(struct sk_buff *pdu)
658{
659	return pdu->data[2] & 0xf;
660}
661
662static void nfc_llcp_set_nrns(struct nfc_llcp_sock *sock, struct sk_buff *pdu)
663{
664	pdu->data[2] = (sock->send_n << 4) | (sock->recv_n);
665	sock->send_n = (sock->send_n + 1) % 16;
666	sock->recv_ack_n = (sock->recv_n - 1) % 16;
667}
668
669void nfc_llcp_send_to_raw_sock(struct nfc_llcp_local *local,
670			       struct sk_buff *skb, u8 direction)
671{
672	struct sk_buff *skb_copy = NULL, *nskb;
673	struct sock *sk;
674	u8 *data;
675
676	read_lock(&local->raw_sockets.lock);
677
678	sk_for_each(sk, &local->raw_sockets.head) {
679		if (sk->sk_state != LLCP_BOUND)
680			continue;
681
682		if (skb_copy == NULL) {
683			skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE,
684						      GFP_ATOMIC, true);
685
686			if (skb_copy == NULL)
687				continue;
688
689			data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE);
690
691			data[0] = local->dev ? local->dev->idx : 0xFF;
692			data[1] = direction & 0x01;
693			data[1] |= (RAW_PAYLOAD_LLCP << 1);
694		}
695
696		nskb = skb_clone(skb_copy, GFP_ATOMIC);
697		if (!nskb)
698			continue;
699
700		if (sock_queue_rcv_skb(sk, nskb))
701			kfree_skb(nskb);
702	}
703
704	read_unlock(&local->raw_sockets.lock);
705
706	kfree_skb(skb_copy);
707}
708
709static void nfc_llcp_tx_work(struct work_struct *work)
710{
711	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
712						    tx_work);
713	struct sk_buff *skb;
714	struct sock *sk;
715	struct nfc_llcp_sock *llcp_sock;
716
717	skb = skb_dequeue(&local->tx_queue);
718	if (skb != NULL) {
719		sk = skb->sk;
720		llcp_sock = nfc_llcp_sock(sk);
721
722		if (llcp_sock == NULL && nfc_llcp_ptype(skb) == LLCP_PDU_I) {
723			kfree_skb(skb);
724			nfc_llcp_send_symm(local->dev);
725		} else if (llcp_sock && !llcp_sock->remote_ready) {
726			skb_queue_head(&local->tx_queue, skb);
727			nfc_llcp_send_symm(local->dev);
728		} else {
729			struct sk_buff *copy_skb = NULL;
730			u8 ptype = nfc_llcp_ptype(skb);
731			int ret;
732
733			pr_debug("Sending pending skb\n");
734			print_hex_dump(KERN_DEBUG, "LLCP Tx: ",
735				       DUMP_PREFIX_OFFSET, 16, 1,
736				       skb->data, skb->len, true);
737
738			if (ptype == LLCP_PDU_DISC && sk != NULL &&
739			    sk->sk_state == LLCP_DISCONNECTING) {
740				nfc_llcp_sock_unlink(&local->sockets, sk);
741				sock_orphan(sk);
742				sock_put(sk);
743			}
744
745			if (ptype == LLCP_PDU_I)
746				copy_skb = skb_copy(skb, GFP_ATOMIC);
747
748			__net_timestamp(skb);
749
750			nfc_llcp_send_to_raw_sock(local, skb,
751						  NFC_DIRECTION_TX);
752
753			ret = nfc_data_exchange(local->dev, local->target_idx,
754						skb, nfc_llcp_recv, local);
755
756			if (ret) {
757				kfree_skb(copy_skb);
758				goto out;
759			}
760
761			if (ptype == LLCP_PDU_I && copy_skb)
762				skb_queue_tail(&llcp_sock->tx_pending_queue,
763					       copy_skb);
764		}
765	} else {
766		nfc_llcp_send_symm(local->dev);
767	}
768
769out:
770	mod_timer(&local->link_timer,
771		  jiffies + msecs_to_jiffies(2 * local->remote_lto));
772}
773
774static struct nfc_llcp_sock *nfc_llcp_connecting_sock_get(struct nfc_llcp_local *local,
775							  u8 ssap)
776{
777	struct sock *sk;
778	struct nfc_llcp_sock *llcp_sock;
779
780	read_lock(&local->connecting_sockets.lock);
781
782	sk_for_each(sk, &local->connecting_sockets.head) {
783		llcp_sock = nfc_llcp_sock(sk);
784
785		if (llcp_sock->ssap == ssap) {
786			sock_hold(&llcp_sock->sk);
787			goto out;
788		}
789	}
790
791	llcp_sock = NULL;
792
793out:
794	read_unlock(&local->connecting_sockets.lock);
795
796	return llcp_sock;
797}
798
799static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
800						  u8 *sn, size_t sn_len)
801{
802	struct nfc_llcp_sock *llcp_sock;
803
804	llcp_sock = nfc_llcp_sock_from_sn(local, sn, sn_len);
805
806	if (llcp_sock == NULL)
807		return NULL;
808
809	sock_hold(&llcp_sock->sk);
810
811	return llcp_sock;
812}
813
814static u8 *nfc_llcp_connect_sn(struct sk_buff *skb, size_t *sn_len)
815{
816	u8 *tlv = &skb->data[2], type, length;
817	size_t tlv_array_len = skb->len - LLCP_HEADER_SIZE, offset = 0;
818
819	while (offset < tlv_array_len) {
820		type = tlv[0];
821		length = tlv[1];
822
823		pr_debug("type 0x%x length %d\n", type, length);
824
825		if (type == LLCP_TLV_SN) {
826			*sn_len = length;
827			return &tlv[2];
828		}
829
830		offset += length + 2;
831		tlv += length + 2;
832	}
833
834	return NULL;
835}
836
837static void nfc_llcp_recv_ui(struct nfc_llcp_local *local,
838			     struct sk_buff *skb)
839{
840	struct nfc_llcp_sock *llcp_sock;
841	struct nfc_llcp_ui_cb *ui_cb;
842	u8 dsap, ssap;
843
844	dsap = nfc_llcp_dsap(skb);
845	ssap = nfc_llcp_ssap(skb);
846
847	ui_cb = nfc_llcp_ui_skb_cb(skb);
848	ui_cb->dsap = dsap;
849	ui_cb->ssap = ssap;
850
851	pr_debug("%d %d\n", dsap, ssap);
852
853	/* We're looking for a bound socket, not a client one */
854	llcp_sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
855	if (llcp_sock == NULL || llcp_sock->sk.sk_type != SOCK_DGRAM)
856		return;
857
858	/* There is no sequence with UI frames */
859	skb_pull(skb, LLCP_HEADER_SIZE);
860	if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
861		/*
862		 * UI frames will be freed from the socket layer, so we
863		 * need to keep them alive until someone receives them.
864		 */
865		skb_get(skb);
866	} else {
867		pr_err("Receive queue is full\n");
868	}
869
870	nfc_llcp_sock_put(llcp_sock);
871}
872
873static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
874				  struct sk_buff *skb)
875{
876	struct sock *new_sk, *parent;
877	struct nfc_llcp_sock *sock, *new_sock;
878	u8 dsap, ssap, reason;
879
880	dsap = nfc_llcp_dsap(skb);
881	ssap = nfc_llcp_ssap(skb);
882
883	pr_debug("%d %d\n", dsap, ssap);
884
885	if (dsap != LLCP_SAP_SDP) {
886		sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
887		if (sock == NULL || sock->sk.sk_state != LLCP_LISTEN) {
888			reason = LLCP_DM_NOBOUND;
889			goto fail;
890		}
891	} else {
892		u8 *sn;
893		size_t sn_len;
894
895		sn = nfc_llcp_connect_sn(skb, &sn_len);
896		if (sn == NULL) {
897			reason = LLCP_DM_NOBOUND;
898			goto fail;
899		}
900
901		pr_debug("Service name length %zu\n", sn_len);
902
903		sock = nfc_llcp_sock_get_sn(local, sn, sn_len);
904		if (sock == NULL) {
905			reason = LLCP_DM_NOBOUND;
906			goto fail;
907		}
908	}
909
910	lock_sock(&sock->sk);
911
912	parent = &sock->sk;
913
914	if (sk_acceptq_is_full(parent)) {
915		reason = LLCP_DM_REJ;
916		release_sock(&sock->sk);
917		sock_put(&sock->sk);
918		goto fail;
919	}
920
921	if (sock->ssap == LLCP_SDP_UNBOUND) {
922		u8 ssap = nfc_llcp_reserve_sdp_ssap(local);
923
924		pr_debug("First client, reserving %d\n", ssap);
925
926		if (ssap == LLCP_SAP_MAX) {
927			reason = LLCP_DM_REJ;
928			release_sock(&sock->sk);
929			sock_put(&sock->sk);
930			goto fail;
931		}
932
933		sock->ssap = ssap;
934	}
935
936	new_sk = nfc_llcp_sock_alloc(NULL, parent->sk_type, GFP_ATOMIC);
937	if (new_sk == NULL) {
938		reason = LLCP_DM_REJ;
939		release_sock(&sock->sk);
940		sock_put(&sock->sk);
941		goto fail;
942	}
943
944	new_sock = nfc_llcp_sock(new_sk);
945	new_sock->dev = local->dev;
946	new_sock->local = nfc_llcp_local_get(local);
947	new_sock->rw = sock->rw;
948	new_sock->miux = sock->miux;
949	new_sock->nfc_protocol = sock->nfc_protocol;
950	new_sock->dsap = ssap;
951	new_sock->target_idx = local->target_idx;
952	new_sock->parent = parent;
953	new_sock->ssap = sock->ssap;
954	if (sock->ssap < LLCP_LOCAL_NUM_SAP && sock->ssap >= LLCP_WKS_NUM_SAP) {
955		atomic_t *client_count;
956
957		pr_debug("reserved_ssap %d for %p\n", sock->ssap, new_sock);
958
959		client_count =
960			&local->local_sdp_cnt[sock->ssap - LLCP_WKS_NUM_SAP];
961
962		atomic_inc(client_count);
963		new_sock->reserved_ssap = sock->ssap;
964	}
965
966	nfc_llcp_parse_connection_tlv(new_sock, &skb->data[LLCP_HEADER_SIZE],
967				      skb->len - LLCP_HEADER_SIZE);
968
969	pr_debug("new sock %p sk %p\n", new_sock, &new_sock->sk);
970
971	nfc_llcp_sock_link(&local->sockets, new_sk);
972
973	nfc_llcp_accept_enqueue(&sock->sk, new_sk);
974
975	nfc_get_device(local->dev->idx);
976
977	new_sk->sk_state = LLCP_CONNECTED;
978
979	/* Wake the listening processes */
980	parent->sk_data_ready(parent);
981
982	/* Send CC */
983	nfc_llcp_send_cc(new_sock);
984
985	release_sock(&sock->sk);
986	sock_put(&sock->sk);
987
988	return;
989
990fail:
991	/* Send DM */
992	nfc_llcp_send_dm(local, dsap, ssap, reason);
993}
994
995int nfc_llcp_queue_i_frames(struct nfc_llcp_sock *sock)
996{
997	int nr_frames = 0;
998	struct nfc_llcp_local *local = sock->local;
999
1000	pr_debug("Remote ready %d tx queue len %d remote rw %d",
1001		 sock->remote_ready, skb_queue_len(&sock->tx_pending_queue),
1002		 sock->remote_rw);
1003
1004	/* Try to queue some I frames for transmission */
1005	while (sock->remote_ready &&
1006	       skb_queue_len(&sock->tx_pending_queue) < sock->remote_rw) {
1007		struct sk_buff *pdu;
1008
1009		pdu = skb_dequeue(&sock->tx_queue);
1010		if (pdu == NULL)
1011			break;
1012
1013		/* Update N(S)/N(R) */
1014		nfc_llcp_set_nrns(sock, pdu);
1015
1016		skb_queue_tail(&local->tx_queue, pdu);
1017		nr_frames++;
1018	}
1019
1020	return nr_frames;
1021}
1022
1023static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local,
1024			       struct sk_buff *skb)
1025{
1026	struct nfc_llcp_sock *llcp_sock;
1027	struct sock *sk;
1028	u8 dsap, ssap, ptype, ns, nr;
1029
1030	ptype = nfc_llcp_ptype(skb);
1031	dsap = nfc_llcp_dsap(skb);
1032	ssap = nfc_llcp_ssap(skb);
1033	ns = nfc_llcp_ns(skb);
1034	nr = nfc_llcp_nr(skb);
1035
1036	pr_debug("%d %d R %d S %d\n", dsap, ssap, nr, ns);
1037
1038	llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1039	if (llcp_sock == NULL) {
1040		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1041		return;
1042	}
1043
1044	sk = &llcp_sock->sk;
1045	lock_sock(sk);
1046	if (sk->sk_state == LLCP_CLOSED) {
1047		release_sock(sk);
1048		nfc_llcp_sock_put(llcp_sock);
1049	}
1050
1051	/* Pass the payload upstream */
1052	if (ptype == LLCP_PDU_I) {
1053		pr_debug("I frame, queueing on %p\n", &llcp_sock->sk);
1054
1055		if (ns == llcp_sock->recv_n)
1056			llcp_sock->recv_n = (llcp_sock->recv_n + 1) % 16;
1057		else
1058			pr_err("Received out of sequence I PDU\n");
1059
1060		skb_pull(skb, LLCP_HEADER_SIZE + LLCP_SEQUENCE_SIZE);
1061		if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
1062			/*
1063			 * I frames will be freed from the socket layer, so we
1064			 * need to keep them alive until someone receives them.
1065			 */
1066			skb_get(skb);
1067		} else {
1068			pr_err("Receive queue is full\n");
1069		}
1070	}
1071
1072	/* Remove skbs from the pending queue */
1073	if (llcp_sock->send_ack_n != nr) {
1074		struct sk_buff *s, *tmp;
1075		u8 n;
1076
1077		llcp_sock->send_ack_n = nr;
1078
1079		/* Remove and free all skbs until ns == nr */
1080		skb_queue_walk_safe(&llcp_sock->tx_pending_queue, s, tmp) {
1081			n = nfc_llcp_ns(s);
1082
1083			skb_unlink(s, &llcp_sock->tx_pending_queue);
1084			kfree_skb(s);
1085
1086			if (n == nr)
1087				break;
1088		}
1089
1090		/* Re-queue the remaining skbs for transmission */
1091		skb_queue_reverse_walk_safe(&llcp_sock->tx_pending_queue,
1092					    s, tmp) {
1093			skb_unlink(s, &llcp_sock->tx_pending_queue);
1094			skb_queue_head(&local->tx_queue, s);
1095		}
1096	}
1097
1098	if (ptype == LLCP_PDU_RR)
1099		llcp_sock->remote_ready = true;
1100	else if (ptype == LLCP_PDU_RNR)
1101		llcp_sock->remote_ready = false;
1102
1103	if (nfc_llcp_queue_i_frames(llcp_sock) == 0 && ptype == LLCP_PDU_I)
1104		nfc_llcp_send_rr(llcp_sock);
1105
1106	release_sock(sk);
1107	nfc_llcp_sock_put(llcp_sock);
1108}
1109
1110static void nfc_llcp_recv_disc(struct nfc_llcp_local *local,
1111			       struct sk_buff *skb)
1112{
1113	struct nfc_llcp_sock *llcp_sock;
1114	struct sock *sk;
1115	u8 dsap, ssap;
1116
1117	dsap = nfc_llcp_dsap(skb);
1118	ssap = nfc_llcp_ssap(skb);
1119
1120	if ((dsap == 0) && (ssap == 0)) {
1121		pr_debug("Connection termination");
1122		nfc_dep_link_down(local->dev);
1123		return;
1124	}
1125
1126	llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1127	if (llcp_sock == NULL) {
1128		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1129		return;
1130	}
1131
1132	sk = &llcp_sock->sk;
1133	lock_sock(sk);
1134
1135	nfc_llcp_socket_purge(llcp_sock);
1136
1137	if (sk->sk_state == LLCP_CLOSED) {
1138		release_sock(sk);
1139		nfc_llcp_sock_put(llcp_sock);
1140	}
1141
1142	if (sk->sk_state == LLCP_CONNECTED) {
1143		nfc_put_device(local->dev);
1144		sk->sk_state = LLCP_CLOSED;
1145		sk->sk_state_change(sk);
1146	}
1147
1148	nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_DISC);
1149
1150	release_sock(sk);
1151	nfc_llcp_sock_put(llcp_sock);
1152}
1153
1154static void nfc_llcp_recv_cc(struct nfc_llcp_local *local, struct sk_buff *skb)
1155{
1156	struct nfc_llcp_sock *llcp_sock;
1157	struct sock *sk;
1158	u8 dsap, ssap;
1159
1160	dsap = nfc_llcp_dsap(skb);
1161	ssap = nfc_llcp_ssap(skb);
1162
1163	llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1164	if (llcp_sock == NULL) {
1165		pr_err("Invalid CC\n");
1166		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1167
1168		return;
1169	}
1170
1171	sk = &llcp_sock->sk;
1172
1173	/* Unlink from connecting and link to the client array */
1174	nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
1175	nfc_llcp_sock_link(&local->sockets, sk);
1176	llcp_sock->dsap = ssap;
1177
1178	nfc_llcp_parse_connection_tlv(llcp_sock, &skb->data[LLCP_HEADER_SIZE],
1179				      skb->len - LLCP_HEADER_SIZE);
1180
1181	sk->sk_state = LLCP_CONNECTED;
1182	sk->sk_state_change(sk);
1183
1184	nfc_llcp_sock_put(llcp_sock);
1185}
1186
1187static void nfc_llcp_recv_dm(struct nfc_llcp_local *local, struct sk_buff *skb)
1188{
1189	struct nfc_llcp_sock *llcp_sock;
1190	struct sock *sk;
1191	u8 dsap, ssap, reason;
1192
1193	dsap = nfc_llcp_dsap(skb);
1194	ssap = nfc_llcp_ssap(skb);
1195	reason = skb->data[2];
1196
1197	pr_debug("%d %d reason %d\n", ssap, dsap, reason);
1198
1199	switch (reason) {
1200	case LLCP_DM_NOBOUND:
1201	case LLCP_DM_REJ:
1202		llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1203		break;
1204
1205	default:
1206		llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1207		break;
1208	}
1209
1210	if (llcp_sock == NULL) {
1211		pr_debug("Already closed\n");
1212		return;
1213	}
1214
1215	sk = &llcp_sock->sk;
1216
1217	sk->sk_err = ENXIO;
1218	sk->sk_state = LLCP_CLOSED;
1219	sk->sk_state_change(sk);
1220
1221	nfc_llcp_sock_put(llcp_sock);
1222}
1223
1224static void nfc_llcp_recv_snl(struct nfc_llcp_local *local,
1225			      struct sk_buff *skb)
1226{
1227	struct nfc_llcp_sock *llcp_sock;
1228	u8 dsap, ssap, *tlv, type, length, tid, sap;
1229	u16 tlv_len, offset;
1230	char *service_name;
1231	size_t service_name_len;
1232	struct nfc_llcp_sdp_tlv *sdp;
1233	HLIST_HEAD(llc_sdres_list);
1234	size_t sdres_tlvs_len;
1235	HLIST_HEAD(nl_sdres_list);
1236
1237	dsap = nfc_llcp_dsap(skb);
1238	ssap = nfc_llcp_ssap(skb);
1239
1240	pr_debug("%d %d\n", dsap, ssap);
1241
1242	if (dsap != LLCP_SAP_SDP || ssap != LLCP_SAP_SDP) {
1243		pr_err("Wrong SNL SAP\n");
1244		return;
1245	}
1246
1247	tlv = &skb->data[LLCP_HEADER_SIZE];
1248	tlv_len = skb->len - LLCP_HEADER_SIZE;
1249	offset = 0;
1250	sdres_tlvs_len = 0;
1251
1252	while (offset < tlv_len) {
1253		type = tlv[0];
1254		length = tlv[1];
1255
1256		switch (type) {
1257		case LLCP_TLV_SDREQ:
1258			tid = tlv[2];
1259			service_name = (char *) &tlv[3];
1260			service_name_len = length - 1;
1261
1262			pr_debug("Looking for %.16s\n", service_name);
1263
1264			if (service_name_len == strlen("urn:nfc:sn:sdp") &&
1265			    !strncmp(service_name, "urn:nfc:sn:sdp",
1266				     service_name_len)) {
1267				sap = 1;
1268				goto add_snl;
1269			}
1270
1271			llcp_sock = nfc_llcp_sock_from_sn(local, service_name,
1272							  service_name_len);
1273			if (!llcp_sock) {
1274				sap = 0;
1275				goto add_snl;
1276			}
1277
1278			/*
1279			 * We found a socket but its ssap has not been reserved
1280			 * yet. We need to assign it for good and send a reply.
1281			 * The ssap will be freed when the socket is closed.
1282			 */
1283			if (llcp_sock->ssap == LLCP_SDP_UNBOUND) {
1284				atomic_t *client_count;
1285
1286				sap = nfc_llcp_reserve_sdp_ssap(local);
1287
1288				pr_debug("Reserving %d\n", sap);
1289
1290				if (sap == LLCP_SAP_MAX) {
1291					sap = 0;
1292					goto add_snl;
1293				}
1294
1295				client_count =
1296					&local->local_sdp_cnt[sap -
1297							      LLCP_WKS_NUM_SAP];
1298
1299				atomic_inc(client_count);
1300
1301				llcp_sock->ssap = sap;
1302				llcp_sock->reserved_ssap = sap;
1303			} else {
1304				sap = llcp_sock->ssap;
1305			}
1306
1307			pr_debug("%p %d\n", llcp_sock, sap);
1308
1309add_snl:
1310			sdp = nfc_llcp_build_sdres_tlv(tid, sap);
1311			if (sdp == NULL)
1312				goto exit;
1313
1314			sdres_tlvs_len += sdp->tlv_len;
1315			hlist_add_head(&sdp->node, &llc_sdres_list);
1316			break;
1317
1318		case LLCP_TLV_SDRES:
1319			mutex_lock(&local->sdreq_lock);
1320
1321			pr_debug("LLCP_TLV_SDRES: searching tid %d\n", tlv[2]);
1322
1323			hlist_for_each_entry(sdp, &local->pending_sdreqs, node) {
1324				if (sdp->tid != tlv[2])
1325					continue;
1326
1327				sdp->sap = tlv[3];
1328
1329				pr_debug("Found: uri=%s, sap=%d\n",
1330					 sdp->uri, sdp->sap);
1331
1332				hlist_del(&sdp->node);
1333
1334				hlist_add_head(&sdp->node, &nl_sdres_list);
1335
1336				break;
1337			}
1338
1339			mutex_unlock(&local->sdreq_lock);
1340			break;
1341
1342		default:
1343			pr_err("Invalid SNL tlv value 0x%x\n", type);
1344			break;
1345		}
1346
1347		offset += length + 2;
1348		tlv += length + 2;
1349	}
1350
1351exit:
1352	if (!hlist_empty(&nl_sdres_list))
1353		nfc_genl_llc_send_sdres(local->dev, &nl_sdres_list);
1354
1355	if (!hlist_empty(&llc_sdres_list))
1356		nfc_llcp_send_snl_sdres(local, &llc_sdres_list, sdres_tlvs_len);
1357}
1358
1359static void nfc_llcp_recv_agf(struct nfc_llcp_local *local, struct sk_buff *skb)
1360{
1361	u8 ptype;
1362	u16 pdu_len;
1363	struct sk_buff *new_skb;
1364
1365	if (skb->len <= LLCP_HEADER_SIZE) {
1366		pr_err("Malformed AGF PDU\n");
1367		return;
1368	}
1369
1370	skb_pull(skb, LLCP_HEADER_SIZE);
1371
1372	while (skb->len > LLCP_AGF_PDU_HEADER_SIZE) {
1373		pdu_len = skb->data[0] << 8 | skb->data[1];
1374
1375		skb_pull(skb, LLCP_AGF_PDU_HEADER_SIZE);
1376
1377		if (pdu_len < LLCP_HEADER_SIZE || pdu_len > skb->len) {
1378			pr_err("Malformed AGF PDU\n");
1379			return;
1380		}
1381
1382		ptype = nfc_llcp_ptype(skb);
1383
1384		if (ptype == LLCP_PDU_SYMM || ptype == LLCP_PDU_AGF)
1385			goto next;
1386
1387		new_skb = nfc_alloc_recv_skb(pdu_len, GFP_KERNEL);
1388		if (new_skb == NULL) {
1389			pr_err("Could not allocate PDU\n");
1390			return;
1391		}
1392
1393		memcpy(skb_put(new_skb, pdu_len), skb->data, pdu_len);
1394
1395		nfc_llcp_rx_skb(local, new_skb);
1396
1397		kfree_skb(new_skb);
1398next:
1399		skb_pull(skb, pdu_len);
1400	}
1401}
1402
1403static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb)
1404{
1405	u8 dsap, ssap, ptype;
1406
1407	ptype = nfc_llcp_ptype(skb);
1408	dsap = nfc_llcp_dsap(skb);
1409	ssap = nfc_llcp_ssap(skb);
1410
1411	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
1412
1413	if (ptype != LLCP_PDU_SYMM)
1414		print_hex_dump(KERN_DEBUG, "LLCP Rx: ", DUMP_PREFIX_OFFSET,
1415			       16, 1, skb->data, skb->len, true);
1416
1417	switch (ptype) {
1418	case LLCP_PDU_SYMM:
1419		pr_debug("SYMM\n");
1420		break;
1421
1422	case LLCP_PDU_UI:
1423		pr_debug("UI\n");
1424		nfc_llcp_recv_ui(local, skb);
1425		break;
1426
1427	case LLCP_PDU_CONNECT:
1428		pr_debug("CONNECT\n");
1429		nfc_llcp_recv_connect(local, skb);
1430		break;
1431
1432	case LLCP_PDU_DISC:
1433		pr_debug("DISC\n");
1434		nfc_llcp_recv_disc(local, skb);
1435		break;
1436
1437	case LLCP_PDU_CC:
1438		pr_debug("CC\n");
1439		nfc_llcp_recv_cc(local, skb);
1440		break;
1441
1442	case LLCP_PDU_DM:
1443		pr_debug("DM\n");
1444		nfc_llcp_recv_dm(local, skb);
1445		break;
1446
1447	case LLCP_PDU_SNL:
1448		pr_debug("SNL\n");
1449		nfc_llcp_recv_snl(local, skb);
1450		break;
1451
1452	case LLCP_PDU_I:
1453	case LLCP_PDU_RR:
1454	case LLCP_PDU_RNR:
1455		pr_debug("I frame\n");
1456		nfc_llcp_recv_hdlc(local, skb);
1457		break;
1458
1459	case LLCP_PDU_AGF:
1460		pr_debug("AGF frame\n");
1461		nfc_llcp_recv_agf(local, skb);
1462		break;
1463	}
1464}
1465
1466static void nfc_llcp_rx_work(struct work_struct *work)
1467{
1468	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
1469						    rx_work);
1470	struct sk_buff *skb;
1471
1472	skb = local->rx_pending;
1473	if (skb == NULL) {
1474		pr_debug("No pending SKB\n");
1475		return;
1476	}
1477
1478	__net_timestamp(skb);
1479
1480	nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_RX);
1481
1482	nfc_llcp_rx_skb(local, skb);
1483
1484	schedule_work(&local->tx_work);
1485	kfree_skb(local->rx_pending);
1486	local->rx_pending = NULL;
1487}
1488
1489static void __nfc_llcp_recv(struct nfc_llcp_local *local, struct sk_buff *skb)
1490{
1491	local->rx_pending = skb;
1492	del_timer(&local->link_timer);
1493	schedule_work(&local->rx_work);
1494}
1495
1496void nfc_llcp_recv(void *data, struct sk_buff *skb, int err)
1497{
1498	struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
1499
1500	pr_debug("Received an LLCP PDU\n");
1501	if (err < 0) {
1502		pr_err("err %d\n", err);
1503		return;
1504	}
1505
1506	__nfc_llcp_recv(local, skb);
1507}
1508
1509int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb)
1510{
1511	struct nfc_llcp_local *local;
1512
1513	local = nfc_llcp_find_local(dev);
1514	if (local == NULL)
1515		return -ENODEV;
1516
1517	__nfc_llcp_recv(local, skb);
1518
1519	return 0;
1520}
1521
1522void nfc_llcp_mac_is_down(struct nfc_dev *dev)
1523{
1524	struct nfc_llcp_local *local;
1525
1526	local = nfc_llcp_find_local(dev);
1527	if (local == NULL)
1528		return;
1529
1530	local->remote_miu = LLCP_DEFAULT_MIU;
1531	local->remote_lto = LLCP_DEFAULT_LTO;
1532
1533	/* Close and purge all existing sockets */
1534	nfc_llcp_socket_release(local, true, 0);
1535}
1536
1537void nfc_llcp_mac_is_up(struct nfc_dev *dev, u32 target_idx,
1538			u8 comm_mode, u8 rf_mode)
1539{
1540	struct nfc_llcp_local *local;
1541
1542	pr_debug("rf mode %d\n", rf_mode);
1543
1544	local = nfc_llcp_find_local(dev);
1545	if (local == NULL)
1546		return;
1547
1548	local->target_idx = target_idx;
1549	local->comm_mode = comm_mode;
1550	local->rf_mode = rf_mode;
1551
1552	if (rf_mode == NFC_RF_INITIATOR) {
1553		pr_debug("Queueing Tx work\n");
1554
1555		schedule_work(&local->tx_work);
1556	} else {
1557		mod_timer(&local->link_timer,
1558			  jiffies + msecs_to_jiffies(local->remote_lto));
1559	}
1560}
1561
1562int nfc_llcp_register_device(struct nfc_dev *ndev)
1563{
1564	struct nfc_llcp_local *local;
1565
1566	local = kzalloc(sizeof(struct nfc_llcp_local), GFP_KERNEL);
1567	if (local == NULL)
1568		return -ENOMEM;
1569
1570	local->dev = ndev;
1571	INIT_LIST_HEAD(&local->list);
1572	kref_init(&local->ref);
1573	mutex_init(&local->sdp_lock);
1574	init_timer(&local->link_timer);
1575	local->link_timer.data = (unsigned long) local;
1576	local->link_timer.function = nfc_llcp_symm_timer;
1577
1578	skb_queue_head_init(&local->tx_queue);
1579	INIT_WORK(&local->tx_work, nfc_llcp_tx_work);
1580
1581	local->rx_pending = NULL;
1582	INIT_WORK(&local->rx_work, nfc_llcp_rx_work);
1583
1584	INIT_WORK(&local->timeout_work, nfc_llcp_timeout_work);
1585
1586	rwlock_init(&local->sockets.lock);
1587	rwlock_init(&local->connecting_sockets.lock);
1588	rwlock_init(&local->raw_sockets.lock);
1589
1590	local->lto = 150; /* 1500 ms */
1591	local->rw = LLCP_MAX_RW;
1592	local->miux = cpu_to_be16(LLCP_MAX_MIUX);
1593	local->local_wks = 0x1; /* LLC Link Management */
1594
1595	nfc_llcp_build_gb(local);
1596
1597	local->remote_miu = LLCP_DEFAULT_MIU;
1598	local->remote_lto = LLCP_DEFAULT_LTO;
1599
1600	mutex_init(&local->sdreq_lock);
1601	INIT_HLIST_HEAD(&local->pending_sdreqs);
1602	init_timer(&local->sdreq_timer);
1603	local->sdreq_timer.data = (unsigned long) local;
1604	local->sdreq_timer.function = nfc_llcp_sdreq_timer;
1605	INIT_WORK(&local->sdreq_timeout_work, nfc_llcp_sdreq_timeout_work);
1606
1607	list_add(&local->list, &llcp_devices);
1608
1609	return 0;
1610}
1611
1612void nfc_llcp_unregister_device(struct nfc_dev *dev)
1613{
1614	struct nfc_llcp_local *local = nfc_llcp_find_local(dev);
1615
1616	if (local == NULL) {
1617		pr_debug("No such device\n");
1618		return;
1619	}
1620
1621	local_cleanup(local);
1622
1623	nfc_llcp_local_put(local);
1624}
1625
1626int __init nfc_llcp_init(void)
1627{
1628	return nfc_llcp_sock_init();
1629}
1630
1631void nfc_llcp_exit(void)
1632{
1633	nfc_llcp_sock_exit();
1634}
1635