1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2011  Intel Corporation. All rights reserved.
4 * Copyright (C) 2014 Marvell International Ltd.
5 */
6
7#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
8
9#include <linux/init.h>
10#include <linux/kernel.h>
11#include <linux/list.h>
12#include <linux/nfc.h>
13
14#include "nfc.h"
15#include "llcp.h"
16
17static u8 llcp_magic[3] = {0x46, 0x66, 0x6d};
18
19static LIST_HEAD(llcp_devices);
20/* Protects llcp_devices list */
21static DEFINE_SPINLOCK(llcp_devices_lock);
22
23static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb);
24
25void nfc_llcp_sock_link(struct llcp_sock_list *l, struct sock *sk)
26{
27	write_lock(&l->lock);
28	sk_add_node(sk, &l->head);
29	write_unlock(&l->lock);
30}
31
32void nfc_llcp_sock_unlink(struct llcp_sock_list *l, struct sock *sk)
33{
34	write_lock(&l->lock);
35	sk_del_node_init(sk);
36	write_unlock(&l->lock);
37}
38
39void nfc_llcp_socket_remote_param_init(struct nfc_llcp_sock *sock)
40{
41	sock->remote_rw = LLCP_DEFAULT_RW;
42	sock->remote_miu = LLCP_MAX_MIU + 1;
43}
44
45static void nfc_llcp_socket_purge(struct nfc_llcp_sock *sock)
46{
47	struct nfc_llcp_local *local = sock->local;
48	struct sk_buff *s, *tmp;
49
50	skb_queue_purge(&sock->tx_queue);
51	skb_queue_purge(&sock->tx_pending_queue);
52
53	if (local == NULL)
54		return;
55
56	/* Search for local pending SKBs that are related to this socket */
57	skb_queue_walk_safe(&local->tx_queue, s, tmp) {
58		if (s->sk != &sock->sk)
59			continue;
60
61		skb_unlink(s, &local->tx_queue);
62		kfree_skb(s);
63	}
64}
65
66static void nfc_llcp_socket_release(struct nfc_llcp_local *local, bool device,
67				    int err)
68{
69	struct sock *sk;
70	struct hlist_node *tmp;
71	struct nfc_llcp_sock *llcp_sock;
72
73	skb_queue_purge(&local->tx_queue);
74
75	write_lock(&local->sockets.lock);
76
77	sk_for_each_safe(sk, tmp, &local->sockets.head) {
78		llcp_sock = nfc_llcp_sock(sk);
79
80		bh_lock_sock(sk);
81
82		nfc_llcp_socket_purge(llcp_sock);
83
84		if (sk->sk_state == LLCP_CONNECTED)
85			nfc_put_device(llcp_sock->dev);
86
87		if (sk->sk_state == LLCP_LISTEN) {
88			struct nfc_llcp_sock *lsk, *n;
89			struct sock *accept_sk;
90
91			list_for_each_entry_safe(lsk, n,
92						 &llcp_sock->accept_queue,
93						 accept_queue) {
94				accept_sk = &lsk->sk;
95				bh_lock_sock(accept_sk);
96
97				nfc_llcp_accept_unlink(accept_sk);
98
99				if (err)
100					accept_sk->sk_err = err;
101				accept_sk->sk_state = LLCP_CLOSED;
102				accept_sk->sk_state_change(sk);
103
104				bh_unlock_sock(accept_sk);
105			}
106		}
107
108		if (err)
109			sk->sk_err = err;
110		sk->sk_state = LLCP_CLOSED;
111		sk->sk_state_change(sk);
112
113		bh_unlock_sock(sk);
114
115		sk_del_node_init(sk);
116	}
117
118	write_unlock(&local->sockets.lock);
119
120	/* If we still have a device, we keep the RAW sockets alive */
121	if (device == true)
122		return;
123
124	write_lock(&local->raw_sockets.lock);
125
126	sk_for_each_safe(sk, tmp, &local->raw_sockets.head) {
127		llcp_sock = nfc_llcp_sock(sk);
128
129		bh_lock_sock(sk);
130
131		nfc_llcp_socket_purge(llcp_sock);
132
133		if (err)
134			sk->sk_err = err;
135		sk->sk_state = LLCP_CLOSED;
136		sk->sk_state_change(sk);
137
138		bh_unlock_sock(sk);
139
140		sk_del_node_init(sk);
141	}
142
143	write_unlock(&local->raw_sockets.lock);
144}
145
146static struct nfc_llcp_local *nfc_llcp_local_get(struct nfc_llcp_local *local)
147{
148	/* Since using nfc_llcp_local may result in usage of nfc_dev, whenever
149	 * we hold a reference to local, we also need to hold a reference to
150	 * the device to avoid UAF.
151	 */
152	if (!nfc_get_device(local->dev->idx))
153		return NULL;
154
155	kref_get(&local->ref);
156
157	return local;
158}
159
160static void local_cleanup(struct nfc_llcp_local *local)
161{
162	nfc_llcp_socket_release(local, false, ENXIO);
163	del_timer_sync(&local->link_timer);
164	skb_queue_purge(&local->tx_queue);
165	cancel_work_sync(&local->tx_work);
166	cancel_work_sync(&local->rx_work);
167	cancel_work_sync(&local->timeout_work);
168	kfree_skb(local->rx_pending);
169	local->rx_pending = NULL;
170	del_timer_sync(&local->sdreq_timer);
171	cancel_work_sync(&local->sdreq_timeout_work);
172	nfc_llcp_free_sdp_tlv_list(&local->pending_sdreqs);
173}
174
175static void local_release(struct kref *ref)
176{
177	struct nfc_llcp_local *local;
178
179	local = container_of(ref, struct nfc_llcp_local, ref);
180
181	local_cleanup(local);
182	kfree(local);
183}
184
185int nfc_llcp_local_put(struct nfc_llcp_local *local)
186{
187	struct nfc_dev *dev;
188	int ret;
189
190	if (local == NULL)
191		return 0;
192
193	dev = local->dev;
194
195	ret = kref_put(&local->ref, local_release);
196	nfc_put_device(dev);
197
198	return ret;
199}
200
201static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
202					       u8 ssap, u8 dsap)
203{
204	struct sock *sk;
205	struct nfc_llcp_sock *llcp_sock, *tmp_sock;
206
207	pr_debug("ssap dsap %d %d\n", ssap, dsap);
208
209	if (ssap == 0 && dsap == 0)
210		return NULL;
211
212	read_lock(&local->sockets.lock);
213
214	llcp_sock = NULL;
215
216	sk_for_each(sk, &local->sockets.head) {
217		tmp_sock = nfc_llcp_sock(sk);
218
219		if (tmp_sock->ssap == ssap && tmp_sock->dsap == dsap) {
220			llcp_sock = tmp_sock;
221			sock_hold(&llcp_sock->sk);
222			break;
223		}
224	}
225
226	read_unlock(&local->sockets.lock);
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(struct timer_list *t)
245{
246	struct nfc_llcp_local *local = from_timer(local, t, link_timer);
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(struct timer_list *t)
288{
289	struct nfc_llcp_local *local = from_timer(local, t, sdreq_timer);
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	struct nfc_llcp_local *res = NULL;
298
299	spin_lock(&llcp_devices_lock);
300	list_for_each_entry(local, &llcp_devices, list)
301		if (local->dev == dev) {
302			res = nfc_llcp_local_get(local);
303			break;
304		}
305	spin_unlock(&llcp_devices_lock);
306
307	return res;
308}
309
310static struct nfc_llcp_local *nfc_llcp_remove_local(struct nfc_dev *dev)
311{
312	struct nfc_llcp_local *local, *tmp;
313
314	spin_lock(&llcp_devices_lock);
315	list_for_each_entry_safe(local, tmp, &llcp_devices, list)
316		if (local->dev == dev) {
317			list_del(&local->list);
318			spin_unlock(&llcp_devices_lock);
319			return local;
320		}
321	spin_unlock(&llcp_devices_lock);
322
323	pr_warn("Shutting down device not found\n");
324
325	return NULL;
326}
327
328static char *wks[] = {
329	NULL,
330	NULL, /* SDP */
331	"urn:nfc:sn:ip",
332	"urn:nfc:sn:obex",
333	"urn:nfc:sn:snep",
334};
335
336static int nfc_llcp_wks_sap(const char *service_name, size_t service_name_len)
337{
338	int sap, num_wks;
339
340	pr_debug("%s\n", service_name);
341
342	if (service_name == NULL)
343		return -EINVAL;
344
345	num_wks = ARRAY_SIZE(wks);
346
347	for (sap = 0; sap < num_wks; sap++) {
348		if (wks[sap] == NULL)
349			continue;
350
351		if (strncmp(wks[sap], service_name, service_name_len) == 0)
352			return sap;
353	}
354
355	return -EINVAL;
356}
357
358static
359struct nfc_llcp_sock *nfc_llcp_sock_from_sn(struct nfc_llcp_local *local,
360					    const u8 *sn, size_t sn_len,
361					    bool needref)
362{
363	struct sock *sk;
364	struct nfc_llcp_sock *llcp_sock, *tmp_sock;
365
366	pr_debug("sn %zd %p\n", sn_len, sn);
367
368	if (sn == NULL || sn_len == 0)
369		return NULL;
370
371	read_lock(&local->sockets.lock);
372
373	llcp_sock = NULL;
374
375	sk_for_each(sk, &local->sockets.head) {
376		tmp_sock = nfc_llcp_sock(sk);
377
378		pr_debug("llcp sock %p\n", tmp_sock);
379
380		if (tmp_sock->sk.sk_type == SOCK_STREAM &&
381		    tmp_sock->sk.sk_state != LLCP_LISTEN)
382			continue;
383
384		if (tmp_sock->sk.sk_type == SOCK_DGRAM &&
385		    tmp_sock->sk.sk_state != LLCP_BOUND)
386			continue;
387
388		if (tmp_sock->service_name == NULL ||
389		    tmp_sock->service_name_len == 0)
390			continue;
391
392		if (tmp_sock->service_name_len != sn_len)
393			continue;
394
395		if (memcmp(sn, tmp_sock->service_name, sn_len) == 0) {
396			llcp_sock = tmp_sock;
397			if (needref)
398				sock_hold(&llcp_sock->sk);
399			break;
400		}
401	}
402
403	read_unlock(&local->sockets.lock);
404
405	pr_debug("Found llcp sock %p\n", llcp_sock);
406
407	return llcp_sock;
408}
409
410u8 nfc_llcp_get_sdp_ssap(struct nfc_llcp_local *local,
411			 struct nfc_llcp_sock *sock)
412{
413	mutex_lock(&local->sdp_lock);
414
415	if (sock->service_name != NULL && sock->service_name_len > 0) {
416		int ssap = nfc_llcp_wks_sap(sock->service_name,
417					    sock->service_name_len);
418
419		if (ssap > 0) {
420			pr_debug("WKS %d\n", ssap);
421
422			/* This is a WKS, let's check if it's free */
423			if (test_bit(ssap, &local->local_wks)) {
424				mutex_unlock(&local->sdp_lock);
425
426				return LLCP_SAP_MAX;
427			}
428
429			set_bit(ssap, &local->local_wks);
430			mutex_unlock(&local->sdp_lock);
431
432			return ssap;
433		}
434
435		/*
436		 * Check if there already is a non WKS socket bound
437		 * to this service name.
438		 */
439		if (nfc_llcp_sock_from_sn(local, sock->service_name,
440					  sock->service_name_len,
441					  false) != NULL) {
442			mutex_unlock(&local->sdp_lock);
443
444			return LLCP_SAP_MAX;
445		}
446
447		mutex_unlock(&local->sdp_lock);
448
449		return LLCP_SDP_UNBOUND;
450
451	} else if (sock->ssap != 0 && sock->ssap < LLCP_WKS_NUM_SAP) {
452		if (!test_bit(sock->ssap, &local->local_wks)) {
453			set_bit(sock->ssap, &local->local_wks);
454			mutex_unlock(&local->sdp_lock);
455
456			return sock->ssap;
457		}
458	}
459
460	mutex_unlock(&local->sdp_lock);
461
462	return LLCP_SAP_MAX;
463}
464
465u8 nfc_llcp_get_local_ssap(struct nfc_llcp_local *local)
466{
467	u8 local_ssap;
468
469	mutex_lock(&local->sdp_lock);
470
471	local_ssap = find_first_zero_bit(&local->local_sap, LLCP_LOCAL_NUM_SAP);
472	if (local_ssap == LLCP_LOCAL_NUM_SAP) {
473		mutex_unlock(&local->sdp_lock);
474		return LLCP_SAP_MAX;
475	}
476
477	set_bit(local_ssap, &local->local_sap);
478
479	mutex_unlock(&local->sdp_lock);
480
481	return local_ssap + LLCP_LOCAL_SAP_OFFSET;
482}
483
484void nfc_llcp_put_ssap(struct nfc_llcp_local *local, u8 ssap)
485{
486	u8 local_ssap;
487	unsigned long *sdp;
488
489	if (ssap < LLCP_WKS_NUM_SAP) {
490		local_ssap = ssap;
491		sdp = &local->local_wks;
492	} else if (ssap < LLCP_LOCAL_NUM_SAP) {
493		atomic_t *client_cnt;
494
495		local_ssap = ssap - LLCP_WKS_NUM_SAP;
496		sdp = &local->local_sdp;
497		client_cnt = &local->local_sdp_cnt[local_ssap];
498
499		pr_debug("%d clients\n", atomic_read(client_cnt));
500
501		mutex_lock(&local->sdp_lock);
502
503		if (atomic_dec_and_test(client_cnt)) {
504			struct nfc_llcp_sock *l_sock;
505
506			pr_debug("No more clients for SAP %d\n", ssap);
507
508			clear_bit(local_ssap, sdp);
509
510			/* Find the listening sock and set it back to UNBOUND */
511			l_sock = nfc_llcp_sock_get(local, ssap, LLCP_SAP_SDP);
512			if (l_sock) {
513				l_sock->ssap = LLCP_SDP_UNBOUND;
514				nfc_llcp_sock_put(l_sock);
515			}
516		}
517
518		mutex_unlock(&local->sdp_lock);
519
520		return;
521	} else if (ssap < LLCP_MAX_SAP) {
522		local_ssap = ssap - LLCP_LOCAL_NUM_SAP;
523		sdp = &local->local_sap;
524	} else {
525		return;
526	}
527
528	mutex_lock(&local->sdp_lock);
529
530	clear_bit(local_ssap, sdp);
531
532	mutex_unlock(&local->sdp_lock);
533}
534
535static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
536{
537	u8 ssap;
538
539	mutex_lock(&local->sdp_lock);
540
541	ssap = find_first_zero_bit(&local->local_sdp, LLCP_SDP_NUM_SAP);
542	if (ssap == LLCP_SDP_NUM_SAP) {
543		mutex_unlock(&local->sdp_lock);
544
545		return LLCP_SAP_MAX;
546	}
547
548	pr_debug("SDP ssap %d\n", LLCP_WKS_NUM_SAP + ssap);
549
550	set_bit(ssap, &local->local_sdp);
551
552	mutex_unlock(&local->sdp_lock);
553
554	return LLCP_WKS_NUM_SAP + ssap;
555}
556
557static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
558{
559	u8 *gb_cur, version, version_length;
560	u8 lto_length, wks_length, miux_length;
561	const u8 *version_tlv = NULL, *lto_tlv = NULL,
562	   *wks_tlv = NULL, *miux_tlv = NULL;
563	__be16 wks = cpu_to_be16(local->local_wks);
564	u8 gb_len = 0;
565	int ret = 0;
566
567	version = LLCP_VERSION_11;
568	version_tlv = nfc_llcp_build_tlv(LLCP_TLV_VERSION, &version,
569					 1, &version_length);
570	if (!version_tlv) {
571		ret = -ENOMEM;
572		goto out;
573	}
574	gb_len += version_length;
575
576	lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &local->lto, 1, &lto_length);
577	if (!lto_tlv) {
578		ret = -ENOMEM;
579		goto out;
580	}
581	gb_len += lto_length;
582
583	pr_debug("Local wks 0x%lx\n", local->local_wks);
584	wks_tlv = nfc_llcp_build_tlv(LLCP_TLV_WKS, (u8 *)&wks, 2, &wks_length);
585	if (!wks_tlv) {
586		ret = -ENOMEM;
587		goto out;
588	}
589	gb_len += wks_length;
590
591	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
592				      &miux_length);
593	if (!miux_tlv) {
594		ret = -ENOMEM;
595		goto out;
596	}
597	gb_len += miux_length;
598
599	gb_len += ARRAY_SIZE(llcp_magic);
600
601	if (gb_len > NFC_MAX_GT_LEN) {
602		ret = -EINVAL;
603		goto out;
604	}
605
606	gb_cur = local->gb;
607
608	memcpy(gb_cur, llcp_magic, ARRAY_SIZE(llcp_magic));
609	gb_cur += ARRAY_SIZE(llcp_magic);
610
611	memcpy(gb_cur, version_tlv, version_length);
612	gb_cur += version_length;
613
614	memcpy(gb_cur, lto_tlv, lto_length);
615	gb_cur += lto_length;
616
617	memcpy(gb_cur, wks_tlv, wks_length);
618	gb_cur += wks_length;
619
620	memcpy(gb_cur, miux_tlv, miux_length);
621	gb_cur += miux_length;
622
623	local->gb_len = gb_len;
624
625out:
626	kfree(version_tlv);
627	kfree(lto_tlv);
628	kfree(wks_tlv);
629	kfree(miux_tlv);
630
631	return ret;
632}
633
634u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len)
635{
636	struct nfc_llcp_local *local;
637
638	local = nfc_llcp_find_local(dev);
639	if (local == NULL) {
640		*general_bytes_len = 0;
641		return NULL;
642	}
643
644	nfc_llcp_build_gb(local);
645
646	*general_bytes_len = local->gb_len;
647
648	nfc_llcp_local_put(local);
649
650	return local->gb;
651}
652
653int nfc_llcp_set_remote_gb(struct nfc_dev *dev, const u8 *gb, u8 gb_len)
654{
655	struct nfc_llcp_local *local;
656	int err;
657
658	if (gb_len < 3 || gb_len > NFC_MAX_GT_LEN)
659		return -EINVAL;
660
661	local = nfc_llcp_find_local(dev);
662	if (local == NULL) {
663		pr_err("No LLCP device\n");
664		return -ENODEV;
665	}
666
667	memset(local->remote_gb, 0, NFC_MAX_GT_LEN);
668	memcpy(local->remote_gb, gb, gb_len);
669	local->remote_gb_len = gb_len;
670
671	if (memcmp(local->remote_gb, llcp_magic, 3)) {
672		pr_err("MAC does not support LLCP\n");
673		err = -EINVAL;
674		goto out;
675	}
676
677	err = nfc_llcp_parse_gb_tlv(local,
678				     &local->remote_gb[3],
679				     local->remote_gb_len - 3);
680out:
681	nfc_llcp_local_put(local);
682	return err;
683}
684
685static u8 nfc_llcp_dsap(const struct sk_buff *pdu)
686{
687	return (pdu->data[0] & 0xfc) >> 2;
688}
689
690static u8 nfc_llcp_ptype(const struct sk_buff *pdu)
691{
692	return ((pdu->data[0] & 0x03) << 2) | ((pdu->data[1] & 0xc0) >> 6);
693}
694
695static u8 nfc_llcp_ssap(const struct sk_buff *pdu)
696{
697	return pdu->data[1] & 0x3f;
698}
699
700static u8 nfc_llcp_ns(const struct sk_buff *pdu)
701{
702	return pdu->data[2] >> 4;
703}
704
705static u8 nfc_llcp_nr(const struct sk_buff *pdu)
706{
707	return pdu->data[2] & 0xf;
708}
709
710static void nfc_llcp_set_nrns(struct nfc_llcp_sock *sock, struct sk_buff *pdu)
711{
712	pdu->data[2] = (sock->send_n << 4) | (sock->recv_n);
713	sock->send_n = (sock->send_n + 1) % 16;
714	sock->recv_ack_n = (sock->recv_n - 1) % 16;
715}
716
717void nfc_llcp_send_to_raw_sock(struct nfc_llcp_local *local,
718			       struct sk_buff *skb, u8 direction)
719{
720	struct sk_buff *skb_copy = NULL, *nskb;
721	struct sock *sk;
722	u8 *data;
723
724	read_lock(&local->raw_sockets.lock);
725
726	sk_for_each(sk, &local->raw_sockets.head) {
727		if (sk->sk_state != LLCP_BOUND)
728			continue;
729
730		if (skb_copy == NULL) {
731			skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE,
732						      GFP_ATOMIC, true);
733
734			if (skb_copy == NULL)
735				continue;
736
737			data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE);
738
739			data[0] = local->dev ? local->dev->idx : 0xFF;
740			data[1] = direction & 0x01;
741			data[1] |= (RAW_PAYLOAD_LLCP << 1);
742		}
743
744		nskb = skb_clone(skb_copy, GFP_ATOMIC);
745		if (!nskb)
746			continue;
747
748		if (sock_queue_rcv_skb(sk, nskb))
749			kfree_skb(nskb);
750	}
751
752	read_unlock(&local->raw_sockets.lock);
753
754	kfree_skb(skb_copy);
755}
756
757static void nfc_llcp_tx_work(struct work_struct *work)
758{
759	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
760						    tx_work);
761	struct sk_buff *skb;
762	struct sock *sk;
763	struct nfc_llcp_sock *llcp_sock;
764
765	skb = skb_dequeue(&local->tx_queue);
766	if (skb != NULL) {
767		sk = skb->sk;
768		llcp_sock = nfc_llcp_sock(sk);
769
770		if (llcp_sock == NULL && nfc_llcp_ptype(skb) == LLCP_PDU_I) {
771			kfree_skb(skb);
772			nfc_llcp_send_symm(local->dev);
773		} else if (llcp_sock && !llcp_sock->remote_ready) {
774			skb_queue_head(&local->tx_queue, skb);
775			nfc_llcp_send_symm(local->dev);
776		} else {
777			struct sk_buff *copy_skb = NULL;
778			u8 ptype = nfc_llcp_ptype(skb);
779			int ret;
780
781			pr_debug("Sending pending skb\n");
782			print_hex_dump_debug("LLCP Tx: ", DUMP_PREFIX_OFFSET,
783					     16, 1, skb->data, skb->len, true);
784
785			if (ptype == LLCP_PDU_I)
786				copy_skb = skb_copy(skb, GFP_ATOMIC);
787
788			__net_timestamp(skb);
789
790			nfc_llcp_send_to_raw_sock(local, skb,
791						  NFC_DIRECTION_TX);
792
793			ret = nfc_data_exchange(local->dev, local->target_idx,
794						skb, nfc_llcp_recv, local);
795
796			if (ret) {
797				kfree_skb(copy_skb);
798				goto out;
799			}
800
801			if (ptype == LLCP_PDU_I && copy_skb)
802				skb_queue_tail(&llcp_sock->tx_pending_queue,
803					       copy_skb);
804		}
805	} else {
806		nfc_llcp_send_symm(local->dev);
807	}
808
809out:
810	mod_timer(&local->link_timer,
811		  jiffies + msecs_to_jiffies(2 * local->remote_lto));
812}
813
814static struct nfc_llcp_sock *nfc_llcp_connecting_sock_get(struct nfc_llcp_local *local,
815							  u8 ssap)
816{
817	struct sock *sk;
818	struct nfc_llcp_sock *llcp_sock;
819
820	read_lock(&local->connecting_sockets.lock);
821
822	sk_for_each(sk, &local->connecting_sockets.head) {
823		llcp_sock = nfc_llcp_sock(sk);
824
825		if (llcp_sock->ssap == ssap) {
826			sock_hold(&llcp_sock->sk);
827			goto out;
828		}
829	}
830
831	llcp_sock = NULL;
832
833out:
834	read_unlock(&local->connecting_sockets.lock);
835
836	return llcp_sock;
837}
838
839static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
840						  const u8 *sn, size_t sn_len)
841{
842	return nfc_llcp_sock_from_sn(local, sn, sn_len, true);
843}
844
845static const u8 *nfc_llcp_connect_sn(const struct sk_buff *skb, size_t *sn_len)
846{
847	u8 type, length;
848	const u8 *tlv = &skb->data[2];
849	size_t tlv_array_len = skb->len - LLCP_HEADER_SIZE, offset = 0;
850
851	while (offset < tlv_array_len) {
852		type = tlv[0];
853		length = tlv[1];
854
855		pr_debug("type 0x%x length %d\n", type, length);
856
857		if (type == LLCP_TLV_SN) {
858			*sn_len = length;
859			return &tlv[2];
860		}
861
862		offset += length + 2;
863		tlv += length + 2;
864	}
865
866	return NULL;
867}
868
869static void nfc_llcp_recv_ui(struct nfc_llcp_local *local,
870			     struct sk_buff *skb)
871{
872	struct nfc_llcp_sock *llcp_sock;
873	struct nfc_llcp_ui_cb *ui_cb;
874	u8 dsap, ssap;
875
876	dsap = nfc_llcp_dsap(skb);
877	ssap = nfc_llcp_ssap(skb);
878
879	ui_cb = nfc_llcp_ui_skb_cb(skb);
880	ui_cb->dsap = dsap;
881	ui_cb->ssap = ssap;
882
883	pr_debug("%d %d\n", dsap, ssap);
884
885	/* We're looking for a bound socket, not a client one */
886	llcp_sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
887	if (llcp_sock == NULL || llcp_sock->sk.sk_type != SOCK_DGRAM)
888		return;
889
890	/* There is no sequence with UI frames */
891	skb_pull(skb, LLCP_HEADER_SIZE);
892	if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
893		/*
894		 * UI frames will be freed from the socket layer, so we
895		 * need to keep them alive until someone receives them.
896		 */
897		skb_get(skb);
898	} else {
899		pr_err("Receive queue is full\n");
900	}
901
902	nfc_llcp_sock_put(llcp_sock);
903}
904
905static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
906				  const struct sk_buff *skb)
907{
908	struct sock *new_sk, *parent;
909	struct nfc_llcp_sock *sock, *new_sock;
910	u8 dsap, ssap, reason;
911
912	dsap = nfc_llcp_dsap(skb);
913	ssap = nfc_llcp_ssap(skb);
914
915	pr_debug("%d %d\n", dsap, ssap);
916
917	if (dsap != LLCP_SAP_SDP) {
918		sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
919		if (sock == NULL || sock->sk.sk_state != LLCP_LISTEN) {
920			reason = LLCP_DM_NOBOUND;
921			goto fail;
922		}
923	} else {
924		const u8 *sn;
925		size_t sn_len;
926
927		sn = nfc_llcp_connect_sn(skb, &sn_len);
928		if (sn == NULL) {
929			reason = LLCP_DM_NOBOUND;
930			goto fail;
931		}
932
933		pr_debug("Service name length %zu\n", sn_len);
934
935		sock = nfc_llcp_sock_get_sn(local, sn, sn_len);
936		if (sock == NULL) {
937			reason = LLCP_DM_NOBOUND;
938			goto fail;
939		}
940	}
941
942	lock_sock(&sock->sk);
943
944	parent = &sock->sk;
945
946	if (sk_acceptq_is_full(parent)) {
947		reason = LLCP_DM_REJ;
948		release_sock(&sock->sk);
949		sock_put(&sock->sk);
950		goto fail;
951	}
952
953	if (sock->ssap == LLCP_SDP_UNBOUND) {
954		u8 ssap = nfc_llcp_reserve_sdp_ssap(local);
955
956		pr_debug("First client, reserving %d\n", ssap);
957
958		if (ssap == LLCP_SAP_MAX) {
959			reason = LLCP_DM_REJ;
960			release_sock(&sock->sk);
961			sock_put(&sock->sk);
962			goto fail;
963		}
964
965		sock->ssap = ssap;
966	}
967
968	new_sk = nfc_llcp_sock_alloc(NULL, parent->sk_type, GFP_ATOMIC, 0);
969	if (new_sk == NULL) {
970		reason = LLCP_DM_REJ;
971		release_sock(&sock->sk);
972		sock_put(&sock->sk);
973		goto fail;
974	}
975
976	new_sock = nfc_llcp_sock(new_sk);
977
978	new_sock->local = nfc_llcp_local_get(local);
979	if (!new_sock->local) {
980		reason = LLCP_DM_REJ;
981		sock_put(&new_sock->sk);
982		release_sock(&sock->sk);
983		sock_put(&sock->sk);
984		goto fail;
985	}
986
987	new_sock->dev = local->dev;
988	new_sock->rw = sock->rw;
989	new_sock->miux = sock->miux;
990	new_sock->nfc_protocol = sock->nfc_protocol;
991	new_sock->dsap = ssap;
992	new_sock->target_idx = local->target_idx;
993	new_sock->parent = parent;
994	new_sock->ssap = sock->ssap;
995	if (sock->ssap < LLCP_LOCAL_NUM_SAP && sock->ssap >= LLCP_WKS_NUM_SAP) {
996		atomic_t *client_count;
997
998		pr_debug("reserved_ssap %d for %p\n", sock->ssap, new_sock);
999
1000		client_count =
1001			&local->local_sdp_cnt[sock->ssap - LLCP_WKS_NUM_SAP];
1002
1003		atomic_inc(client_count);
1004		new_sock->reserved_ssap = sock->ssap;
1005	}
1006
1007	nfc_llcp_parse_connection_tlv(new_sock, &skb->data[LLCP_HEADER_SIZE],
1008				      skb->len - LLCP_HEADER_SIZE);
1009
1010	pr_debug("new sock %p sk %p\n", new_sock, &new_sock->sk);
1011
1012	nfc_llcp_sock_link(&local->sockets, new_sk);
1013
1014	nfc_llcp_accept_enqueue(&sock->sk, new_sk);
1015
1016	nfc_get_device(local->dev->idx);
1017
1018	new_sk->sk_state = LLCP_CONNECTED;
1019
1020	/* Wake the listening processes */
1021	parent->sk_data_ready(parent);
1022
1023	/* Send CC */
1024	nfc_llcp_send_cc(new_sock);
1025
1026	release_sock(&sock->sk);
1027	sock_put(&sock->sk);
1028
1029	return;
1030
1031fail:
1032	/* Send DM */
1033	nfc_llcp_send_dm(local, dsap, ssap, reason);
1034}
1035
1036int nfc_llcp_queue_i_frames(struct nfc_llcp_sock *sock)
1037{
1038	int nr_frames = 0;
1039	struct nfc_llcp_local *local = sock->local;
1040
1041	pr_debug("Remote ready %d tx queue len %d remote rw %d",
1042		 sock->remote_ready, skb_queue_len(&sock->tx_pending_queue),
1043		 sock->remote_rw);
1044
1045	/* Try to queue some I frames for transmission */
1046	while (sock->remote_ready &&
1047	       skb_queue_len(&sock->tx_pending_queue) < sock->remote_rw) {
1048		struct sk_buff *pdu;
1049
1050		pdu = skb_dequeue(&sock->tx_queue);
1051		if (pdu == NULL)
1052			break;
1053
1054		/* Update N(S)/N(R) */
1055		nfc_llcp_set_nrns(sock, pdu);
1056
1057		skb_queue_tail(&local->tx_queue, pdu);
1058		nr_frames++;
1059	}
1060
1061	return nr_frames;
1062}
1063
1064static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local,
1065			       struct sk_buff *skb)
1066{
1067	struct nfc_llcp_sock *llcp_sock;
1068	struct sock *sk;
1069	u8 dsap, ssap, ptype, ns, nr;
1070
1071	ptype = nfc_llcp_ptype(skb);
1072	dsap = nfc_llcp_dsap(skb);
1073	ssap = nfc_llcp_ssap(skb);
1074	ns = nfc_llcp_ns(skb);
1075	nr = nfc_llcp_nr(skb);
1076
1077	pr_debug("%d %d R %d S %d\n", dsap, ssap, nr, ns);
1078
1079	llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1080	if (llcp_sock == NULL) {
1081		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1082		return;
1083	}
1084
1085	sk = &llcp_sock->sk;
1086	lock_sock(sk);
1087	if (sk->sk_state == LLCP_CLOSED) {
1088		release_sock(sk);
1089		nfc_llcp_sock_put(llcp_sock);
1090	}
1091
1092	/* Pass the payload upstream */
1093	if (ptype == LLCP_PDU_I) {
1094		pr_debug("I frame, queueing on %p\n", &llcp_sock->sk);
1095
1096		if (ns == llcp_sock->recv_n)
1097			llcp_sock->recv_n = (llcp_sock->recv_n + 1) % 16;
1098		else
1099			pr_err("Received out of sequence I PDU\n");
1100
1101		skb_pull(skb, LLCP_HEADER_SIZE + LLCP_SEQUENCE_SIZE);
1102		if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
1103			/*
1104			 * I frames will be freed from the socket layer, so we
1105			 * need to keep them alive until someone receives them.
1106			 */
1107			skb_get(skb);
1108		} else {
1109			pr_err("Receive queue is full\n");
1110		}
1111	}
1112
1113	/* Remove skbs from the pending queue */
1114	if (llcp_sock->send_ack_n != nr) {
1115		struct sk_buff *s, *tmp;
1116		u8 n;
1117
1118		llcp_sock->send_ack_n = nr;
1119
1120		/* Remove and free all skbs until ns == nr */
1121		skb_queue_walk_safe(&llcp_sock->tx_pending_queue, s, tmp) {
1122			n = nfc_llcp_ns(s);
1123
1124			skb_unlink(s, &llcp_sock->tx_pending_queue);
1125			kfree_skb(s);
1126
1127			if (n == nr)
1128				break;
1129		}
1130
1131		/* Re-queue the remaining skbs for transmission */
1132		skb_queue_reverse_walk_safe(&llcp_sock->tx_pending_queue,
1133					    s, tmp) {
1134			skb_unlink(s, &llcp_sock->tx_pending_queue);
1135			skb_queue_head(&local->tx_queue, s);
1136		}
1137	}
1138
1139	if (ptype == LLCP_PDU_RR)
1140		llcp_sock->remote_ready = true;
1141	else if (ptype == LLCP_PDU_RNR)
1142		llcp_sock->remote_ready = false;
1143
1144	if (nfc_llcp_queue_i_frames(llcp_sock) == 0 && ptype == LLCP_PDU_I)
1145		nfc_llcp_send_rr(llcp_sock);
1146
1147	release_sock(sk);
1148	nfc_llcp_sock_put(llcp_sock);
1149}
1150
1151static void nfc_llcp_recv_disc(struct nfc_llcp_local *local,
1152			       const struct sk_buff *skb)
1153{
1154	struct nfc_llcp_sock *llcp_sock;
1155	struct sock *sk;
1156	u8 dsap, ssap;
1157
1158	dsap = nfc_llcp_dsap(skb);
1159	ssap = nfc_llcp_ssap(skb);
1160
1161	if ((dsap == 0) && (ssap == 0)) {
1162		pr_debug("Connection termination");
1163		nfc_dep_link_down(local->dev);
1164		return;
1165	}
1166
1167	llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1168	if (llcp_sock == NULL) {
1169		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1170		return;
1171	}
1172
1173	sk = &llcp_sock->sk;
1174	lock_sock(sk);
1175
1176	nfc_llcp_socket_purge(llcp_sock);
1177
1178	if (sk->sk_state == LLCP_CLOSED) {
1179		release_sock(sk);
1180		nfc_llcp_sock_put(llcp_sock);
1181	}
1182
1183	if (sk->sk_state == LLCP_CONNECTED) {
1184		nfc_put_device(local->dev);
1185		sk->sk_state = LLCP_CLOSED;
1186		sk->sk_state_change(sk);
1187	}
1188
1189	nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_DISC);
1190
1191	release_sock(sk);
1192	nfc_llcp_sock_put(llcp_sock);
1193}
1194
1195static void nfc_llcp_recv_cc(struct nfc_llcp_local *local,
1196			     const struct sk_buff *skb)
1197{
1198	struct nfc_llcp_sock *llcp_sock;
1199	struct sock *sk;
1200	u8 dsap, ssap;
1201
1202	dsap = nfc_llcp_dsap(skb);
1203	ssap = nfc_llcp_ssap(skb);
1204
1205	llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1206	if (llcp_sock == NULL) {
1207		pr_err("Invalid CC\n");
1208		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1209
1210		return;
1211	}
1212
1213	sk = &llcp_sock->sk;
1214
1215	/* Unlink from connecting and link to the client array */
1216	nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
1217	nfc_llcp_sock_link(&local->sockets, sk);
1218	llcp_sock->dsap = ssap;
1219
1220	nfc_llcp_parse_connection_tlv(llcp_sock, &skb->data[LLCP_HEADER_SIZE],
1221				      skb->len - LLCP_HEADER_SIZE);
1222
1223	sk->sk_state = LLCP_CONNECTED;
1224	sk->sk_state_change(sk);
1225
1226	nfc_llcp_sock_put(llcp_sock);
1227}
1228
1229static void nfc_llcp_recv_dm(struct nfc_llcp_local *local,
1230			     const struct sk_buff *skb)
1231{
1232	struct nfc_llcp_sock *llcp_sock;
1233	struct sock *sk;
1234	u8 dsap, ssap, reason;
1235
1236	dsap = nfc_llcp_dsap(skb);
1237	ssap = nfc_llcp_ssap(skb);
1238	reason = skb->data[2];
1239
1240	pr_debug("%d %d reason %d\n", ssap, dsap, reason);
1241
1242	switch (reason) {
1243	case LLCP_DM_NOBOUND:
1244	case LLCP_DM_REJ:
1245		llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1246		break;
1247
1248	default:
1249		llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1250		break;
1251	}
1252
1253	if (llcp_sock == NULL) {
1254		pr_debug("Already closed\n");
1255		return;
1256	}
1257
1258	sk = &llcp_sock->sk;
1259
1260	sk->sk_err = ENXIO;
1261	sk->sk_state = LLCP_CLOSED;
1262	sk->sk_state_change(sk);
1263
1264	nfc_llcp_sock_put(llcp_sock);
1265}
1266
1267static void nfc_llcp_recv_snl(struct nfc_llcp_local *local,
1268			      const struct sk_buff *skb)
1269{
1270	struct nfc_llcp_sock *llcp_sock;
1271	u8 dsap, ssap, type, length, tid, sap;
1272	const u8 *tlv;
1273	u16 tlv_len, offset;
1274	const char *service_name;
1275	size_t service_name_len;
1276	struct nfc_llcp_sdp_tlv *sdp;
1277	HLIST_HEAD(llc_sdres_list);
1278	size_t sdres_tlvs_len;
1279	HLIST_HEAD(nl_sdres_list);
1280
1281	dsap = nfc_llcp_dsap(skb);
1282	ssap = nfc_llcp_ssap(skb);
1283
1284	pr_debug("%d %d\n", dsap, ssap);
1285
1286	if (dsap != LLCP_SAP_SDP || ssap != LLCP_SAP_SDP) {
1287		pr_err("Wrong SNL SAP\n");
1288		return;
1289	}
1290
1291	tlv = &skb->data[LLCP_HEADER_SIZE];
1292	tlv_len = skb->len - LLCP_HEADER_SIZE;
1293	offset = 0;
1294	sdres_tlvs_len = 0;
1295
1296	while (offset < tlv_len) {
1297		type = tlv[0];
1298		length = tlv[1];
1299
1300		switch (type) {
1301		case LLCP_TLV_SDREQ:
1302			tid = tlv[2];
1303			service_name = (char *) &tlv[3];
1304			service_name_len = length - 1;
1305
1306			pr_debug("Looking for %.16s\n", service_name);
1307
1308			if (service_name_len == strlen("urn:nfc:sn:sdp") &&
1309			    !strncmp(service_name, "urn:nfc:sn:sdp",
1310				     service_name_len)) {
1311				sap = 1;
1312				goto add_snl;
1313			}
1314
1315			llcp_sock = nfc_llcp_sock_from_sn(local, service_name,
1316							  service_name_len,
1317							  true);
1318			if (!llcp_sock) {
1319				sap = 0;
1320				goto add_snl;
1321			}
1322
1323			/*
1324			 * We found a socket but its ssap has not been reserved
1325			 * yet. We need to assign it for good and send a reply.
1326			 * The ssap will be freed when the socket is closed.
1327			 */
1328			if (llcp_sock->ssap == LLCP_SDP_UNBOUND) {
1329				atomic_t *client_count;
1330
1331				sap = nfc_llcp_reserve_sdp_ssap(local);
1332
1333				pr_debug("Reserving %d\n", sap);
1334
1335				if (sap == LLCP_SAP_MAX) {
1336					sap = 0;
1337					nfc_llcp_sock_put(llcp_sock);
1338					goto add_snl;
1339				}
1340
1341				client_count =
1342					&local->local_sdp_cnt[sap -
1343							      LLCP_WKS_NUM_SAP];
1344
1345				atomic_inc(client_count);
1346
1347				llcp_sock->ssap = sap;
1348				llcp_sock->reserved_ssap = sap;
1349			} else {
1350				sap = llcp_sock->ssap;
1351			}
1352
1353			pr_debug("%p %d\n", llcp_sock, sap);
1354
1355			nfc_llcp_sock_put(llcp_sock);
1356add_snl:
1357			sdp = nfc_llcp_build_sdres_tlv(tid, sap);
1358			if (sdp == NULL)
1359				goto exit;
1360
1361			sdres_tlvs_len += sdp->tlv_len;
1362			hlist_add_head(&sdp->node, &llc_sdres_list);
1363			break;
1364
1365		case LLCP_TLV_SDRES:
1366			mutex_lock(&local->sdreq_lock);
1367
1368			pr_debug("LLCP_TLV_SDRES: searching tid %d\n", tlv[2]);
1369
1370			hlist_for_each_entry(sdp, &local->pending_sdreqs, node) {
1371				if (sdp->tid != tlv[2])
1372					continue;
1373
1374				sdp->sap = tlv[3];
1375
1376				pr_debug("Found: uri=%s, sap=%d\n",
1377					 sdp->uri, sdp->sap);
1378
1379				hlist_del(&sdp->node);
1380
1381				hlist_add_head(&sdp->node, &nl_sdres_list);
1382
1383				break;
1384			}
1385
1386			mutex_unlock(&local->sdreq_lock);
1387			break;
1388
1389		default:
1390			pr_err("Invalid SNL tlv value 0x%x\n", type);
1391			break;
1392		}
1393
1394		offset += length + 2;
1395		tlv += length + 2;
1396	}
1397
1398exit:
1399	if (!hlist_empty(&nl_sdres_list))
1400		nfc_genl_llc_send_sdres(local->dev, &nl_sdres_list);
1401
1402	if (!hlist_empty(&llc_sdres_list))
1403		nfc_llcp_send_snl_sdres(local, &llc_sdres_list, sdres_tlvs_len);
1404}
1405
1406static void nfc_llcp_recv_agf(struct nfc_llcp_local *local, struct sk_buff *skb)
1407{
1408	u8 ptype;
1409	u16 pdu_len;
1410	struct sk_buff *new_skb;
1411
1412	if (skb->len <= LLCP_HEADER_SIZE) {
1413		pr_err("Malformed AGF PDU\n");
1414		return;
1415	}
1416
1417	skb_pull(skb, LLCP_HEADER_SIZE);
1418
1419	while (skb->len > LLCP_AGF_PDU_HEADER_SIZE) {
1420		pdu_len = skb->data[0] << 8 | skb->data[1];
1421
1422		skb_pull(skb, LLCP_AGF_PDU_HEADER_SIZE);
1423
1424		if (pdu_len < LLCP_HEADER_SIZE || pdu_len > skb->len) {
1425			pr_err("Malformed AGF PDU\n");
1426			return;
1427		}
1428
1429		ptype = nfc_llcp_ptype(skb);
1430
1431		if (ptype == LLCP_PDU_SYMM || ptype == LLCP_PDU_AGF)
1432			goto next;
1433
1434		new_skb = nfc_alloc_recv_skb(pdu_len, GFP_KERNEL);
1435		if (new_skb == NULL) {
1436			pr_err("Could not allocate PDU\n");
1437			return;
1438		}
1439
1440		skb_put_data(new_skb, skb->data, pdu_len);
1441
1442		nfc_llcp_rx_skb(local, new_skb);
1443
1444		kfree_skb(new_skb);
1445next:
1446		skb_pull(skb, pdu_len);
1447	}
1448}
1449
1450static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb)
1451{
1452	u8 dsap, ssap, ptype;
1453
1454	ptype = nfc_llcp_ptype(skb);
1455	dsap = nfc_llcp_dsap(skb);
1456	ssap = nfc_llcp_ssap(skb);
1457
1458	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
1459
1460	if (ptype != LLCP_PDU_SYMM)
1461		print_hex_dump_debug("LLCP Rx: ", DUMP_PREFIX_OFFSET, 16, 1,
1462				     skb->data, skb->len, true);
1463
1464	switch (ptype) {
1465	case LLCP_PDU_SYMM:
1466		pr_debug("SYMM\n");
1467		break;
1468
1469	case LLCP_PDU_UI:
1470		pr_debug("UI\n");
1471		nfc_llcp_recv_ui(local, skb);
1472		break;
1473
1474	case LLCP_PDU_CONNECT:
1475		pr_debug("CONNECT\n");
1476		nfc_llcp_recv_connect(local, skb);
1477		break;
1478
1479	case LLCP_PDU_DISC:
1480		pr_debug("DISC\n");
1481		nfc_llcp_recv_disc(local, skb);
1482		break;
1483
1484	case LLCP_PDU_CC:
1485		pr_debug("CC\n");
1486		nfc_llcp_recv_cc(local, skb);
1487		break;
1488
1489	case LLCP_PDU_DM:
1490		pr_debug("DM\n");
1491		nfc_llcp_recv_dm(local, skb);
1492		break;
1493
1494	case LLCP_PDU_SNL:
1495		pr_debug("SNL\n");
1496		nfc_llcp_recv_snl(local, skb);
1497		break;
1498
1499	case LLCP_PDU_I:
1500	case LLCP_PDU_RR:
1501	case LLCP_PDU_RNR:
1502		pr_debug("I frame\n");
1503		nfc_llcp_recv_hdlc(local, skb);
1504		break;
1505
1506	case LLCP_PDU_AGF:
1507		pr_debug("AGF frame\n");
1508		nfc_llcp_recv_agf(local, skb);
1509		break;
1510	}
1511}
1512
1513static void nfc_llcp_rx_work(struct work_struct *work)
1514{
1515	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
1516						    rx_work);
1517	struct sk_buff *skb;
1518
1519	skb = local->rx_pending;
1520	if (skb == NULL) {
1521		pr_debug("No pending SKB\n");
1522		return;
1523	}
1524
1525	__net_timestamp(skb);
1526
1527	nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_RX);
1528
1529	nfc_llcp_rx_skb(local, skb);
1530
1531	schedule_work(&local->tx_work);
1532	kfree_skb(local->rx_pending);
1533	local->rx_pending = NULL;
1534}
1535
1536static void __nfc_llcp_recv(struct nfc_llcp_local *local, struct sk_buff *skb)
1537{
1538	local->rx_pending = skb;
1539	del_timer(&local->link_timer);
1540	schedule_work(&local->rx_work);
1541}
1542
1543void nfc_llcp_recv(void *data, struct sk_buff *skb, int err)
1544{
1545	struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
1546
1547	if (err < 0) {
1548		pr_err("LLCP PDU receive err %d\n", err);
1549		return;
1550	}
1551
1552	__nfc_llcp_recv(local, skb);
1553}
1554
1555int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb)
1556{
1557	struct nfc_llcp_local *local;
1558
1559	local = nfc_llcp_find_local(dev);
1560	if (local == NULL) {
1561		kfree_skb(skb);
1562		return -ENODEV;
1563	}
1564
1565	__nfc_llcp_recv(local, skb);
1566
1567	nfc_llcp_local_put(local);
1568
1569	return 0;
1570}
1571
1572void nfc_llcp_mac_is_down(struct nfc_dev *dev)
1573{
1574	struct nfc_llcp_local *local;
1575
1576	local = nfc_llcp_find_local(dev);
1577	if (local == NULL)
1578		return;
1579
1580	local->remote_miu = LLCP_DEFAULT_MIU;
1581	local->remote_lto = LLCP_DEFAULT_LTO;
1582
1583	/* Close and purge all existing sockets */
1584	nfc_llcp_socket_release(local, true, 0);
1585
1586	nfc_llcp_local_put(local);
1587}
1588
1589void nfc_llcp_mac_is_up(struct nfc_dev *dev, u32 target_idx,
1590			u8 comm_mode, u8 rf_mode)
1591{
1592	struct nfc_llcp_local *local;
1593
1594	pr_debug("rf mode %d\n", rf_mode);
1595
1596	local = nfc_llcp_find_local(dev);
1597	if (local == NULL)
1598		return;
1599
1600	local->target_idx = target_idx;
1601	local->comm_mode = comm_mode;
1602	local->rf_mode = rf_mode;
1603
1604	if (rf_mode == NFC_RF_INITIATOR) {
1605		pr_debug("Queueing Tx work\n");
1606
1607		schedule_work(&local->tx_work);
1608	} else {
1609		mod_timer(&local->link_timer,
1610			  jiffies + msecs_to_jiffies(local->remote_lto));
1611	}
1612
1613	nfc_llcp_local_put(local);
1614}
1615
1616int nfc_llcp_register_device(struct nfc_dev *ndev)
1617{
1618	struct nfc_llcp_local *local;
1619
1620	local = kzalloc(sizeof(struct nfc_llcp_local), GFP_KERNEL);
1621	if (local == NULL)
1622		return -ENOMEM;
1623
1624	/* As we are going to initialize local's refcount, we need to get the
1625	 * nfc_dev to avoid UAF, otherwise there is no point in continuing.
1626	 * See nfc_llcp_local_get().
1627	 */
1628	local->dev = nfc_get_device(ndev->idx);
1629	if (!local->dev) {
1630		kfree(local);
1631		return -ENODEV;
1632	}
1633
1634	INIT_LIST_HEAD(&local->list);
1635	kref_init(&local->ref);
1636	mutex_init(&local->sdp_lock);
1637	timer_setup(&local->link_timer, nfc_llcp_symm_timer, 0);
1638
1639	skb_queue_head_init(&local->tx_queue);
1640	INIT_WORK(&local->tx_work, nfc_llcp_tx_work);
1641
1642	local->rx_pending = NULL;
1643	INIT_WORK(&local->rx_work, nfc_llcp_rx_work);
1644
1645	INIT_WORK(&local->timeout_work, nfc_llcp_timeout_work);
1646
1647	rwlock_init(&local->sockets.lock);
1648	rwlock_init(&local->connecting_sockets.lock);
1649	rwlock_init(&local->raw_sockets.lock);
1650
1651	local->lto = 150; /* 1500 ms */
1652	local->rw = LLCP_MAX_RW;
1653	local->miux = cpu_to_be16(LLCP_MAX_MIUX);
1654	local->local_wks = 0x1; /* LLC Link Management */
1655
1656	nfc_llcp_build_gb(local);
1657
1658	local->remote_miu = LLCP_DEFAULT_MIU;
1659	local->remote_lto = LLCP_DEFAULT_LTO;
1660
1661	mutex_init(&local->sdreq_lock);
1662	INIT_HLIST_HEAD(&local->pending_sdreqs);
1663	timer_setup(&local->sdreq_timer, nfc_llcp_sdreq_timer, 0);
1664	INIT_WORK(&local->sdreq_timeout_work, nfc_llcp_sdreq_timeout_work);
1665
1666	spin_lock(&llcp_devices_lock);
1667	list_add(&local->list, &llcp_devices);
1668	spin_unlock(&llcp_devices_lock);
1669
1670	return 0;
1671}
1672
1673void nfc_llcp_unregister_device(struct nfc_dev *dev)
1674{
1675	struct nfc_llcp_local *local = nfc_llcp_remove_local(dev);
1676
1677	if (local == NULL) {
1678		pr_debug("No such device\n");
1679		return;
1680	}
1681
1682	local_cleanup(local);
1683
1684	nfc_llcp_local_put(local);
1685}
1686
1687int __init nfc_llcp_init(void)
1688{
1689	return nfc_llcp_sock_init();
1690}
1691
1692void nfc_llcp_exit(void)
1693{
1694	nfc_llcp_sock_exit();
1695}
1696