xref: /kernel/linux/linux-5.10/net/nfc/llcp_core.c (revision 8c2ecf20)
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	pr_debug("%p\n", &sock->sk);
51
52	skb_queue_purge(&sock->tx_queue);
53	skb_queue_purge(&sock->tx_pending_queue);
54
55	if (local == NULL)
56		return;
57
58	/* Search for local pending SKBs that are related to this socket */
59	skb_queue_walk_safe(&local->tx_queue, s, tmp) {
60		if (s->sk != &sock->sk)
61			continue;
62
63		skb_unlink(s, &local->tx_queue);
64		kfree_skb(s);
65	}
66}
67
68static void nfc_llcp_socket_release(struct nfc_llcp_local *local, bool device,
69				    int err)
70{
71	struct sock *sk;
72	struct hlist_node *tmp;
73	struct nfc_llcp_sock *llcp_sock;
74
75	skb_queue_purge(&local->tx_queue);
76
77	write_lock(&local->sockets.lock);
78
79	sk_for_each_safe(sk, tmp, &local->sockets.head) {
80		llcp_sock = nfc_llcp_sock(sk);
81
82		bh_lock_sock(sk);
83
84		nfc_llcp_socket_purge(llcp_sock);
85
86		if (sk->sk_state == LLCP_CONNECTED)
87			nfc_put_device(llcp_sock->dev);
88
89		if (sk->sk_state == LLCP_LISTEN) {
90			struct nfc_llcp_sock *lsk, *n;
91			struct sock *accept_sk;
92
93			list_for_each_entry_safe(lsk, n,
94						 &llcp_sock->accept_queue,
95						 accept_queue) {
96				accept_sk = &lsk->sk;
97				bh_lock_sock(accept_sk);
98
99				nfc_llcp_accept_unlink(accept_sk);
100
101				if (err)
102					accept_sk->sk_err = err;
103				accept_sk->sk_state = LLCP_CLOSED;
104				accept_sk->sk_state_change(sk);
105
106				bh_unlock_sock(accept_sk);
107			}
108		}
109
110		if (err)
111			sk->sk_err = err;
112		sk->sk_state = LLCP_CLOSED;
113		sk->sk_state_change(sk);
114
115		bh_unlock_sock(sk);
116
117		sk_del_node_init(sk);
118	}
119
120	write_unlock(&local->sockets.lock);
121
122	/* If we still have a device, we keep the RAW sockets alive */
123	if (device == true)
124		return;
125
126	write_lock(&local->raw_sockets.lock);
127
128	sk_for_each_safe(sk, tmp, &local->raw_sockets.head) {
129		llcp_sock = nfc_llcp_sock(sk);
130
131		bh_lock_sock(sk);
132
133		nfc_llcp_socket_purge(llcp_sock);
134
135		if (err)
136			sk->sk_err = err;
137		sk->sk_state = LLCP_CLOSED;
138		sk->sk_state_change(sk);
139
140		bh_unlock_sock(sk);
141
142		sk_del_node_init(sk);
143	}
144
145	write_unlock(&local->raw_sockets.lock);
146}
147
148static struct nfc_llcp_local *nfc_llcp_local_get(struct nfc_llcp_local *local)
149{
150	/* Since using nfc_llcp_local may result in usage of nfc_dev, whenever
151	 * we hold a reference to local, we also need to hold a reference to
152	 * the device to avoid UAF.
153	 */
154	if (!nfc_get_device(local->dev->idx))
155		return NULL;
156
157	kref_get(&local->ref);
158
159	return local;
160}
161
162static void local_cleanup(struct nfc_llcp_local *local)
163{
164	nfc_llcp_socket_release(local, false, ENXIO);
165	del_timer_sync(&local->link_timer);
166	skb_queue_purge(&local->tx_queue);
167	cancel_work_sync(&local->tx_work);
168	cancel_work_sync(&local->rx_work);
169	cancel_work_sync(&local->timeout_work);
170	kfree_skb(local->rx_pending);
171	local->rx_pending = NULL;
172	del_timer_sync(&local->sdreq_timer);
173	cancel_work_sync(&local->sdreq_timeout_work);
174	nfc_llcp_free_sdp_tlv_list(&local->pending_sdreqs);
175}
176
177static void local_release(struct kref *ref)
178{
179	struct nfc_llcp_local *local;
180
181	local = container_of(ref, struct nfc_llcp_local, ref);
182
183	local_cleanup(local);
184	kfree(local);
185}
186
187int nfc_llcp_local_put(struct nfc_llcp_local *local)
188{
189	struct nfc_dev *dev;
190	int ret;
191
192	if (local == NULL)
193		return 0;
194
195	dev = local->dev;
196
197	ret = kref_put(&local->ref, local_release);
198	nfc_put_device(dev);
199
200	return ret;
201}
202
203static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
204					       u8 ssap, u8 dsap)
205{
206	struct sock *sk;
207	struct nfc_llcp_sock *llcp_sock, *tmp_sock;
208
209	pr_debug("ssap dsap %d %d\n", ssap, dsap);
210
211	if (ssap == 0 && dsap == 0)
212		return NULL;
213
214	read_lock(&local->sockets.lock);
215
216	llcp_sock = NULL;
217
218	sk_for_each(sk, &local->sockets.head) {
219		tmp_sock = nfc_llcp_sock(sk);
220
221		if (tmp_sock->ssap == ssap && tmp_sock->dsap == dsap) {
222			llcp_sock = tmp_sock;
223			sock_hold(&llcp_sock->sk);
224			break;
225		}
226	}
227
228	read_unlock(&local->sockets.lock);
229
230	return llcp_sock;
231}
232
233static void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
234{
235	sock_put(&sock->sk);
236}
237
238static void nfc_llcp_timeout_work(struct work_struct *work)
239{
240	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
241						    timeout_work);
242
243	nfc_dep_link_down(local->dev);
244}
245
246static void nfc_llcp_symm_timer(struct timer_list *t)
247{
248	struct nfc_llcp_local *local = from_timer(local, t, link_timer);
249
250	pr_err("SYMM timeout\n");
251
252	schedule_work(&local->timeout_work);
253}
254
255static void nfc_llcp_sdreq_timeout_work(struct work_struct *work)
256{
257	unsigned long time;
258	HLIST_HEAD(nl_sdres_list);
259	struct hlist_node *n;
260	struct nfc_llcp_sdp_tlv *sdp;
261	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
262						    sdreq_timeout_work);
263
264	mutex_lock(&local->sdreq_lock);
265
266	time = jiffies - msecs_to_jiffies(3 * local->remote_lto);
267
268	hlist_for_each_entry_safe(sdp, n, &local->pending_sdreqs, node) {
269		if (time_after(sdp->time, time))
270			continue;
271
272		sdp->sap = LLCP_SDP_UNBOUND;
273
274		hlist_del(&sdp->node);
275
276		hlist_add_head(&sdp->node, &nl_sdres_list);
277	}
278
279	if (!hlist_empty(&local->pending_sdreqs))
280		mod_timer(&local->sdreq_timer,
281			  jiffies + msecs_to_jiffies(3 * local->remote_lto));
282
283	mutex_unlock(&local->sdreq_lock);
284
285	if (!hlist_empty(&nl_sdres_list))
286		nfc_genl_llc_send_sdres(local->dev, &nl_sdres_list);
287}
288
289static void nfc_llcp_sdreq_timer(struct timer_list *t)
290{
291	struct nfc_llcp_local *local = from_timer(local, t, sdreq_timer);
292
293	schedule_work(&local->sdreq_timeout_work);
294}
295
296struct nfc_llcp_local *nfc_llcp_find_local(struct nfc_dev *dev)
297{
298	struct nfc_llcp_local *local;
299	struct nfc_llcp_local *res = NULL;
300
301	spin_lock(&llcp_devices_lock);
302	list_for_each_entry(local, &llcp_devices, list)
303		if (local->dev == dev) {
304			res = nfc_llcp_local_get(local);
305			break;
306		}
307	spin_unlock(&llcp_devices_lock);
308
309	return res;
310}
311
312static struct nfc_llcp_local *nfc_llcp_remove_local(struct nfc_dev *dev)
313{
314	struct nfc_llcp_local *local, *tmp;
315
316	spin_lock(&llcp_devices_lock);
317	list_for_each_entry_safe(local, tmp, &llcp_devices, list)
318		if (local->dev == dev) {
319			list_del(&local->list);
320			spin_unlock(&llcp_devices_lock);
321			return local;
322		}
323	spin_unlock(&llcp_devices_lock);
324
325	pr_warn("Shutting down device not found\n");
326
327	return NULL;
328}
329
330static char *wks[] = {
331	NULL,
332	NULL, /* SDP */
333	"urn:nfc:sn:ip",
334	"urn:nfc:sn:obex",
335	"urn:nfc:sn:snep",
336};
337
338static int nfc_llcp_wks_sap(const char *service_name, size_t service_name_len)
339{
340	int sap, num_wks;
341
342	pr_debug("%s\n", service_name);
343
344	if (service_name == NULL)
345		return -EINVAL;
346
347	num_wks = ARRAY_SIZE(wks);
348
349	for (sap = 0; sap < num_wks; sap++) {
350		if (wks[sap] == NULL)
351			continue;
352
353		if (strncmp(wks[sap], service_name, service_name_len) == 0)
354			return sap;
355	}
356
357	return -EINVAL;
358}
359
360static
361struct nfc_llcp_sock *nfc_llcp_sock_from_sn(struct nfc_llcp_local *local,
362					    const u8 *sn, size_t sn_len,
363					    bool needref)
364{
365	struct sock *sk;
366	struct nfc_llcp_sock *llcp_sock, *tmp_sock;
367
368	pr_debug("sn %zd %p\n", sn_len, sn);
369
370	if (sn == NULL || sn_len == 0)
371		return NULL;
372
373	read_lock(&local->sockets.lock);
374
375	llcp_sock = NULL;
376
377	sk_for_each(sk, &local->sockets.head) {
378		tmp_sock = nfc_llcp_sock(sk);
379
380		pr_debug("llcp sock %p\n", tmp_sock);
381
382		if (tmp_sock->sk.sk_type == SOCK_STREAM &&
383		    tmp_sock->sk.sk_state != LLCP_LISTEN)
384			continue;
385
386		if (tmp_sock->sk.sk_type == SOCK_DGRAM &&
387		    tmp_sock->sk.sk_state != LLCP_BOUND)
388			continue;
389
390		if (tmp_sock->service_name == NULL ||
391		    tmp_sock->service_name_len == 0)
392			continue;
393
394		if (tmp_sock->service_name_len != sn_len)
395			continue;
396
397		if (memcmp(sn, tmp_sock->service_name, sn_len) == 0) {
398			llcp_sock = tmp_sock;
399			if (needref)
400				sock_hold(&llcp_sock->sk);
401			break;
402		}
403	}
404
405	read_unlock(&local->sockets.lock);
406
407	pr_debug("Found llcp sock %p\n", llcp_sock);
408
409	return llcp_sock;
410}
411
412u8 nfc_llcp_get_sdp_ssap(struct nfc_llcp_local *local,
413			 struct nfc_llcp_sock *sock)
414{
415	mutex_lock(&local->sdp_lock);
416
417	if (sock->service_name != NULL && sock->service_name_len > 0) {
418		int ssap = nfc_llcp_wks_sap(sock->service_name,
419					    sock->service_name_len);
420
421		if (ssap > 0) {
422			pr_debug("WKS %d\n", ssap);
423
424			/* This is a WKS, let's check if it's free */
425			if (local->local_wks & BIT(ssap)) {
426				mutex_unlock(&local->sdp_lock);
427
428				return LLCP_SAP_MAX;
429			}
430
431			set_bit(ssap, &local->local_wks);
432			mutex_unlock(&local->sdp_lock);
433
434			return ssap;
435		}
436
437		/*
438		 * Check if there already is a non WKS socket bound
439		 * to this service name.
440		 */
441		if (nfc_llcp_sock_from_sn(local, sock->service_name,
442					  sock->service_name_len,
443					  false) != NULL) {
444			mutex_unlock(&local->sdp_lock);
445
446			return LLCP_SAP_MAX;
447		}
448
449		mutex_unlock(&local->sdp_lock);
450
451		return LLCP_SDP_UNBOUND;
452
453	} else if (sock->ssap != 0 && sock->ssap < LLCP_WKS_NUM_SAP) {
454		if (!test_bit(sock->ssap, &local->local_wks)) {
455			set_bit(sock->ssap, &local->local_wks);
456			mutex_unlock(&local->sdp_lock);
457
458			return sock->ssap;
459		}
460	}
461
462	mutex_unlock(&local->sdp_lock);
463
464	return LLCP_SAP_MAX;
465}
466
467u8 nfc_llcp_get_local_ssap(struct nfc_llcp_local *local)
468{
469	u8 local_ssap;
470
471	mutex_lock(&local->sdp_lock);
472
473	local_ssap = find_first_zero_bit(&local->local_sap, LLCP_LOCAL_NUM_SAP);
474	if (local_ssap == LLCP_LOCAL_NUM_SAP) {
475		mutex_unlock(&local->sdp_lock);
476		return LLCP_SAP_MAX;
477	}
478
479	set_bit(local_ssap, &local->local_sap);
480
481	mutex_unlock(&local->sdp_lock);
482
483	return local_ssap + LLCP_LOCAL_SAP_OFFSET;
484}
485
486void nfc_llcp_put_ssap(struct nfc_llcp_local *local, u8 ssap)
487{
488	u8 local_ssap;
489	unsigned long *sdp;
490
491	if (ssap < LLCP_WKS_NUM_SAP) {
492		local_ssap = ssap;
493		sdp = &local->local_wks;
494	} else if (ssap < LLCP_LOCAL_NUM_SAP) {
495		atomic_t *client_cnt;
496
497		local_ssap = ssap - LLCP_WKS_NUM_SAP;
498		sdp = &local->local_sdp;
499		client_cnt = &local->local_sdp_cnt[local_ssap];
500
501		pr_debug("%d clients\n", atomic_read(client_cnt));
502
503		mutex_lock(&local->sdp_lock);
504
505		if (atomic_dec_and_test(client_cnt)) {
506			struct nfc_llcp_sock *l_sock;
507
508			pr_debug("No more clients for SAP %d\n", ssap);
509
510			clear_bit(local_ssap, sdp);
511
512			/* Find the listening sock and set it back to UNBOUND */
513			l_sock = nfc_llcp_sock_get(local, ssap, LLCP_SAP_SDP);
514			if (l_sock) {
515				l_sock->ssap = LLCP_SDP_UNBOUND;
516				nfc_llcp_sock_put(l_sock);
517			}
518		}
519
520		mutex_unlock(&local->sdp_lock);
521
522		return;
523	} else if (ssap < LLCP_MAX_SAP) {
524		local_ssap = ssap - LLCP_LOCAL_NUM_SAP;
525		sdp = &local->local_sap;
526	} else {
527		return;
528	}
529
530	mutex_lock(&local->sdp_lock);
531
532	clear_bit(local_ssap, sdp);
533
534	mutex_unlock(&local->sdp_lock);
535}
536
537static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
538{
539	u8 ssap;
540
541	mutex_lock(&local->sdp_lock);
542
543	ssap = find_first_zero_bit(&local->local_sdp, LLCP_SDP_NUM_SAP);
544	if (ssap == LLCP_SDP_NUM_SAP) {
545		mutex_unlock(&local->sdp_lock);
546
547		return LLCP_SAP_MAX;
548	}
549
550	pr_debug("SDP ssap %d\n", LLCP_WKS_NUM_SAP + ssap);
551
552	set_bit(ssap, &local->local_sdp);
553
554	mutex_unlock(&local->sdp_lock);
555
556	return LLCP_WKS_NUM_SAP + ssap;
557}
558
559static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
560{
561	u8 *gb_cur, version, version_length;
562	u8 lto_length, wks_length, miux_length;
563	const u8 *version_tlv = NULL, *lto_tlv = NULL,
564	   *wks_tlv = NULL, *miux_tlv = NULL;
565	__be16 wks = cpu_to_be16(local->local_wks);
566	u8 gb_len = 0;
567	int ret = 0;
568
569	version = LLCP_VERSION_11;
570	version_tlv = nfc_llcp_build_tlv(LLCP_TLV_VERSION, &version,
571					 1, &version_length);
572	if (!version_tlv) {
573		ret = -ENOMEM;
574		goto out;
575	}
576	gb_len += version_length;
577
578	lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &local->lto, 1, &lto_length);
579	if (!lto_tlv) {
580		ret = -ENOMEM;
581		goto out;
582	}
583	gb_len += lto_length;
584
585	pr_debug("Local wks 0x%lx\n", local->local_wks);
586	wks_tlv = nfc_llcp_build_tlv(LLCP_TLV_WKS, (u8 *)&wks, 2, &wks_length);
587	if (!wks_tlv) {
588		ret = -ENOMEM;
589		goto out;
590	}
591	gb_len += wks_length;
592
593	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
594				      &miux_length);
595	if (!miux_tlv) {
596		ret = -ENOMEM;
597		goto out;
598	}
599	gb_len += miux_length;
600
601	gb_len += ARRAY_SIZE(llcp_magic);
602
603	if (gb_len > NFC_MAX_GT_LEN) {
604		ret = -EINVAL;
605		goto out;
606	}
607
608	gb_cur = local->gb;
609
610	memcpy(gb_cur, llcp_magic, ARRAY_SIZE(llcp_magic));
611	gb_cur += ARRAY_SIZE(llcp_magic);
612
613	memcpy(gb_cur, version_tlv, version_length);
614	gb_cur += version_length;
615
616	memcpy(gb_cur, lto_tlv, lto_length);
617	gb_cur += lto_length;
618
619	memcpy(gb_cur, wks_tlv, wks_length);
620	gb_cur += wks_length;
621
622	memcpy(gb_cur, miux_tlv, miux_length);
623	gb_cur += miux_length;
624
625	local->gb_len = gb_len;
626
627out:
628	kfree(version_tlv);
629	kfree(lto_tlv);
630	kfree(wks_tlv);
631	kfree(miux_tlv);
632
633	return ret;
634}
635
636u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len)
637{
638	struct nfc_llcp_local *local;
639
640	local = nfc_llcp_find_local(dev);
641	if (local == NULL) {
642		*general_bytes_len = 0;
643		return NULL;
644	}
645
646	nfc_llcp_build_gb(local);
647
648	*general_bytes_len = local->gb_len;
649
650	nfc_llcp_local_put(local);
651
652	return local->gb;
653}
654
655int nfc_llcp_set_remote_gb(struct nfc_dev *dev, const u8 *gb, u8 gb_len)
656{
657	struct nfc_llcp_local *local;
658	int err;
659
660	if (gb_len < 3 || gb_len > NFC_MAX_GT_LEN)
661		return -EINVAL;
662
663	local = nfc_llcp_find_local(dev);
664	if (local == NULL) {
665		pr_err("No LLCP device\n");
666		return -ENODEV;
667	}
668
669	memset(local->remote_gb, 0, NFC_MAX_GT_LEN);
670	memcpy(local->remote_gb, gb, gb_len);
671	local->remote_gb_len = gb_len;
672
673	if (memcmp(local->remote_gb, llcp_magic, 3)) {
674		pr_err("MAC does not support LLCP\n");
675		err = -EINVAL;
676		goto out;
677	}
678
679	err = nfc_llcp_parse_gb_tlv(local,
680				     &local->remote_gb[3],
681				     local->remote_gb_len - 3);
682out:
683	nfc_llcp_local_put(local);
684	return err;
685}
686
687static u8 nfc_llcp_dsap(const struct sk_buff *pdu)
688{
689	return (pdu->data[0] & 0xfc) >> 2;
690}
691
692static u8 nfc_llcp_ptype(const struct sk_buff *pdu)
693{
694	return ((pdu->data[0] & 0x03) << 2) | ((pdu->data[1] & 0xc0) >> 6);
695}
696
697static u8 nfc_llcp_ssap(const struct sk_buff *pdu)
698{
699	return pdu->data[1] & 0x3f;
700}
701
702static u8 nfc_llcp_ns(const struct sk_buff *pdu)
703{
704	return pdu->data[2] >> 4;
705}
706
707static u8 nfc_llcp_nr(const struct sk_buff *pdu)
708{
709	return pdu->data[2] & 0xf;
710}
711
712static void nfc_llcp_set_nrns(struct nfc_llcp_sock *sock, struct sk_buff *pdu)
713{
714	pdu->data[2] = (sock->send_n << 4) | (sock->recv_n);
715	sock->send_n = (sock->send_n + 1) % 16;
716	sock->recv_ack_n = (sock->recv_n - 1) % 16;
717}
718
719void nfc_llcp_send_to_raw_sock(struct nfc_llcp_local *local,
720			       struct sk_buff *skb, u8 direction)
721{
722	struct sk_buff *skb_copy = NULL, *nskb;
723	struct sock *sk;
724	u8 *data;
725
726	read_lock(&local->raw_sockets.lock);
727
728	sk_for_each(sk, &local->raw_sockets.head) {
729		if (sk->sk_state != LLCP_BOUND)
730			continue;
731
732		if (skb_copy == NULL) {
733			skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE,
734						      GFP_ATOMIC, true);
735
736			if (skb_copy == NULL)
737				continue;
738
739			data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE);
740
741			data[0] = local->dev ? local->dev->idx : 0xFF;
742			data[1] = direction & 0x01;
743			data[1] |= (RAW_PAYLOAD_LLCP << 1);
744		}
745
746		nskb = skb_clone(skb_copy, GFP_ATOMIC);
747		if (!nskb)
748			continue;
749
750		if (sock_queue_rcv_skb(sk, nskb))
751			kfree_skb(nskb);
752	}
753
754	read_unlock(&local->raw_sockets.lock);
755
756	kfree_skb(skb_copy);
757}
758
759static void nfc_llcp_tx_work(struct work_struct *work)
760{
761	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
762						    tx_work);
763	struct sk_buff *skb;
764	struct sock *sk;
765	struct nfc_llcp_sock *llcp_sock;
766
767	skb = skb_dequeue(&local->tx_queue);
768	if (skb != NULL) {
769		sk = skb->sk;
770		llcp_sock = nfc_llcp_sock(sk);
771
772		if (llcp_sock == NULL && nfc_llcp_ptype(skb) == LLCP_PDU_I) {
773			kfree_skb(skb);
774			nfc_llcp_send_symm(local->dev);
775		} else if (llcp_sock && !llcp_sock->remote_ready) {
776			skb_queue_head(&local->tx_queue, skb);
777			nfc_llcp_send_symm(local->dev);
778		} else {
779			struct sk_buff *copy_skb = NULL;
780			u8 ptype = nfc_llcp_ptype(skb);
781			int ret;
782
783			pr_debug("Sending pending skb\n");
784			print_hex_dump_debug("LLCP Tx: ", DUMP_PREFIX_OFFSET,
785					     16, 1, skb->data, skb->len, true);
786
787			if (ptype == LLCP_PDU_DISC && sk != NULL &&
788			    sk->sk_state == LLCP_DISCONNECTING) {
789				nfc_llcp_sock_unlink(&local->sockets, sk);
790				sock_orphan(sk);
791				sock_put(sk);
792			}
793
794			if (ptype == LLCP_PDU_I)
795				copy_skb = skb_copy(skb, GFP_ATOMIC);
796
797			__net_timestamp(skb);
798
799			nfc_llcp_send_to_raw_sock(local, skb,
800						  NFC_DIRECTION_TX);
801
802			ret = nfc_data_exchange(local->dev, local->target_idx,
803						skb, nfc_llcp_recv, local);
804
805			if (ret) {
806				kfree_skb(copy_skb);
807				goto out;
808			}
809
810			if (ptype == LLCP_PDU_I && copy_skb)
811				skb_queue_tail(&llcp_sock->tx_pending_queue,
812					       copy_skb);
813		}
814	} else {
815		nfc_llcp_send_symm(local->dev);
816	}
817
818out:
819	mod_timer(&local->link_timer,
820		  jiffies + msecs_to_jiffies(2 * local->remote_lto));
821}
822
823static struct nfc_llcp_sock *nfc_llcp_connecting_sock_get(struct nfc_llcp_local *local,
824							  u8 ssap)
825{
826	struct sock *sk;
827	struct nfc_llcp_sock *llcp_sock;
828
829	read_lock(&local->connecting_sockets.lock);
830
831	sk_for_each(sk, &local->connecting_sockets.head) {
832		llcp_sock = nfc_llcp_sock(sk);
833
834		if (llcp_sock->ssap == ssap) {
835			sock_hold(&llcp_sock->sk);
836			goto out;
837		}
838	}
839
840	llcp_sock = NULL;
841
842out:
843	read_unlock(&local->connecting_sockets.lock);
844
845	return llcp_sock;
846}
847
848static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
849						  const u8 *sn, size_t sn_len)
850{
851	return nfc_llcp_sock_from_sn(local, sn, sn_len, true);
852}
853
854static const u8 *nfc_llcp_connect_sn(const struct sk_buff *skb, size_t *sn_len)
855{
856	u8 type, length;
857	const u8 *tlv = &skb->data[2];
858	size_t tlv_array_len = skb->len - LLCP_HEADER_SIZE, offset = 0;
859
860	while (offset < tlv_array_len) {
861		type = tlv[0];
862		length = tlv[1];
863
864		pr_debug("type 0x%x length %d\n", type, length);
865
866		if (type == LLCP_TLV_SN) {
867			*sn_len = length;
868			return &tlv[2];
869		}
870
871		offset += length + 2;
872		tlv += length + 2;
873	}
874
875	return NULL;
876}
877
878static void nfc_llcp_recv_ui(struct nfc_llcp_local *local,
879			     struct sk_buff *skb)
880{
881	struct nfc_llcp_sock *llcp_sock;
882	struct nfc_llcp_ui_cb *ui_cb;
883	u8 dsap, ssap;
884
885	dsap = nfc_llcp_dsap(skb);
886	ssap = nfc_llcp_ssap(skb);
887
888	ui_cb = nfc_llcp_ui_skb_cb(skb);
889	ui_cb->dsap = dsap;
890	ui_cb->ssap = ssap;
891
892	pr_debug("%d %d\n", dsap, ssap);
893
894	/* We're looking for a bound socket, not a client one */
895	llcp_sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
896	if (llcp_sock == NULL || llcp_sock->sk.sk_type != SOCK_DGRAM)
897		return;
898
899	/* There is no sequence with UI frames */
900	skb_pull(skb, LLCP_HEADER_SIZE);
901	if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
902		/*
903		 * UI frames will be freed from the socket layer, so we
904		 * need to keep them alive until someone receives them.
905		 */
906		skb_get(skb);
907	} else {
908		pr_err("Receive queue is full\n");
909	}
910
911	nfc_llcp_sock_put(llcp_sock);
912}
913
914static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
915				  const struct sk_buff *skb)
916{
917	struct sock *new_sk, *parent;
918	struct nfc_llcp_sock *sock, *new_sock;
919	u8 dsap, ssap, reason;
920
921	dsap = nfc_llcp_dsap(skb);
922	ssap = nfc_llcp_ssap(skb);
923
924	pr_debug("%d %d\n", dsap, ssap);
925
926	if (dsap != LLCP_SAP_SDP) {
927		sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
928		if (sock == NULL || sock->sk.sk_state != LLCP_LISTEN) {
929			reason = LLCP_DM_NOBOUND;
930			goto fail;
931		}
932	} else {
933		const u8 *sn;
934		size_t sn_len;
935
936		sn = nfc_llcp_connect_sn(skb, &sn_len);
937		if (sn == NULL) {
938			reason = LLCP_DM_NOBOUND;
939			goto fail;
940		}
941
942		pr_debug("Service name length %zu\n", sn_len);
943
944		sock = nfc_llcp_sock_get_sn(local, sn, sn_len);
945		if (sock == NULL) {
946			reason = LLCP_DM_NOBOUND;
947			goto fail;
948		}
949	}
950
951	lock_sock(&sock->sk);
952
953	parent = &sock->sk;
954
955	if (sk_acceptq_is_full(parent)) {
956		reason = LLCP_DM_REJ;
957		release_sock(&sock->sk);
958		sock_put(&sock->sk);
959		goto fail;
960	}
961
962	if (sock->ssap == LLCP_SDP_UNBOUND) {
963		u8 ssap = nfc_llcp_reserve_sdp_ssap(local);
964
965		pr_debug("First client, reserving %d\n", ssap);
966
967		if (ssap == LLCP_SAP_MAX) {
968			reason = LLCP_DM_REJ;
969			release_sock(&sock->sk);
970			sock_put(&sock->sk);
971			goto fail;
972		}
973
974		sock->ssap = ssap;
975	}
976
977	new_sk = nfc_llcp_sock_alloc(NULL, parent->sk_type, GFP_ATOMIC, 0);
978	if (new_sk == NULL) {
979		reason = LLCP_DM_REJ;
980		release_sock(&sock->sk);
981		sock_put(&sock->sk);
982		goto fail;
983	}
984
985	new_sock = nfc_llcp_sock(new_sk);
986
987	new_sock->local = nfc_llcp_local_get(local);
988	if (!new_sock->local) {
989		reason = LLCP_DM_REJ;
990		sock_put(&new_sock->sk);
991		release_sock(&sock->sk);
992		sock_put(&sock->sk);
993		goto fail;
994	}
995
996	new_sock->dev = local->dev;
997	new_sock->rw = sock->rw;
998	new_sock->miux = sock->miux;
999	new_sock->nfc_protocol = sock->nfc_protocol;
1000	new_sock->dsap = ssap;
1001	new_sock->target_idx = local->target_idx;
1002	new_sock->parent = parent;
1003	new_sock->ssap = sock->ssap;
1004	if (sock->ssap < LLCP_LOCAL_NUM_SAP && sock->ssap >= LLCP_WKS_NUM_SAP) {
1005		atomic_t *client_count;
1006
1007		pr_debug("reserved_ssap %d for %p\n", sock->ssap, new_sock);
1008
1009		client_count =
1010			&local->local_sdp_cnt[sock->ssap - LLCP_WKS_NUM_SAP];
1011
1012		atomic_inc(client_count);
1013		new_sock->reserved_ssap = sock->ssap;
1014	}
1015
1016	nfc_llcp_parse_connection_tlv(new_sock, &skb->data[LLCP_HEADER_SIZE],
1017				      skb->len - LLCP_HEADER_SIZE);
1018
1019	pr_debug("new sock %p sk %p\n", new_sock, &new_sock->sk);
1020
1021	nfc_llcp_sock_link(&local->sockets, new_sk);
1022
1023	nfc_llcp_accept_enqueue(&sock->sk, new_sk);
1024
1025	nfc_get_device(local->dev->idx);
1026
1027	new_sk->sk_state = LLCP_CONNECTED;
1028
1029	/* Wake the listening processes */
1030	parent->sk_data_ready(parent);
1031
1032	/* Send CC */
1033	nfc_llcp_send_cc(new_sock);
1034
1035	release_sock(&sock->sk);
1036	sock_put(&sock->sk);
1037
1038	return;
1039
1040fail:
1041	/* Send DM */
1042	nfc_llcp_send_dm(local, dsap, ssap, reason);
1043}
1044
1045int nfc_llcp_queue_i_frames(struct nfc_llcp_sock *sock)
1046{
1047	int nr_frames = 0;
1048	struct nfc_llcp_local *local = sock->local;
1049
1050	pr_debug("Remote ready %d tx queue len %d remote rw %d",
1051		 sock->remote_ready, skb_queue_len(&sock->tx_pending_queue),
1052		 sock->remote_rw);
1053
1054	/* Try to queue some I frames for transmission */
1055	while (sock->remote_ready &&
1056	       skb_queue_len(&sock->tx_pending_queue) < sock->remote_rw) {
1057		struct sk_buff *pdu;
1058
1059		pdu = skb_dequeue(&sock->tx_queue);
1060		if (pdu == NULL)
1061			break;
1062
1063		/* Update N(S)/N(R) */
1064		nfc_llcp_set_nrns(sock, pdu);
1065
1066		skb_queue_tail(&local->tx_queue, pdu);
1067		nr_frames++;
1068	}
1069
1070	return nr_frames;
1071}
1072
1073static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local,
1074			       struct sk_buff *skb)
1075{
1076	struct nfc_llcp_sock *llcp_sock;
1077	struct sock *sk;
1078	u8 dsap, ssap, ptype, ns, nr;
1079
1080	ptype = nfc_llcp_ptype(skb);
1081	dsap = nfc_llcp_dsap(skb);
1082	ssap = nfc_llcp_ssap(skb);
1083	ns = nfc_llcp_ns(skb);
1084	nr = nfc_llcp_nr(skb);
1085
1086	pr_debug("%d %d R %d S %d\n", dsap, ssap, nr, ns);
1087
1088	llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1089	if (llcp_sock == NULL) {
1090		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1091		return;
1092	}
1093
1094	sk = &llcp_sock->sk;
1095	lock_sock(sk);
1096	if (sk->sk_state == LLCP_CLOSED) {
1097		release_sock(sk);
1098		nfc_llcp_sock_put(llcp_sock);
1099	}
1100
1101	/* Pass the payload upstream */
1102	if (ptype == LLCP_PDU_I) {
1103		pr_debug("I frame, queueing on %p\n", &llcp_sock->sk);
1104
1105		if (ns == llcp_sock->recv_n)
1106			llcp_sock->recv_n = (llcp_sock->recv_n + 1) % 16;
1107		else
1108			pr_err("Received out of sequence I PDU\n");
1109
1110		skb_pull(skb, LLCP_HEADER_SIZE + LLCP_SEQUENCE_SIZE);
1111		if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
1112			/*
1113			 * I frames will be freed from the socket layer, so we
1114			 * need to keep them alive until someone receives them.
1115			 */
1116			skb_get(skb);
1117		} else {
1118			pr_err("Receive queue is full\n");
1119		}
1120	}
1121
1122	/* Remove skbs from the pending queue */
1123	if (llcp_sock->send_ack_n != nr) {
1124		struct sk_buff *s, *tmp;
1125		u8 n;
1126
1127		llcp_sock->send_ack_n = nr;
1128
1129		/* Remove and free all skbs until ns == nr */
1130		skb_queue_walk_safe(&llcp_sock->tx_pending_queue, s, tmp) {
1131			n = nfc_llcp_ns(s);
1132
1133			skb_unlink(s, &llcp_sock->tx_pending_queue);
1134			kfree_skb(s);
1135
1136			if (n == nr)
1137				break;
1138		}
1139
1140		/* Re-queue the remaining skbs for transmission */
1141		skb_queue_reverse_walk_safe(&llcp_sock->tx_pending_queue,
1142					    s, tmp) {
1143			skb_unlink(s, &llcp_sock->tx_pending_queue);
1144			skb_queue_head(&local->tx_queue, s);
1145		}
1146	}
1147
1148	if (ptype == LLCP_PDU_RR)
1149		llcp_sock->remote_ready = true;
1150	else if (ptype == LLCP_PDU_RNR)
1151		llcp_sock->remote_ready = false;
1152
1153	if (nfc_llcp_queue_i_frames(llcp_sock) == 0 && ptype == LLCP_PDU_I)
1154		nfc_llcp_send_rr(llcp_sock);
1155
1156	release_sock(sk);
1157	nfc_llcp_sock_put(llcp_sock);
1158}
1159
1160static void nfc_llcp_recv_disc(struct nfc_llcp_local *local,
1161			       const struct sk_buff *skb)
1162{
1163	struct nfc_llcp_sock *llcp_sock;
1164	struct sock *sk;
1165	u8 dsap, ssap;
1166
1167	dsap = nfc_llcp_dsap(skb);
1168	ssap = nfc_llcp_ssap(skb);
1169
1170	if ((dsap == 0) && (ssap == 0)) {
1171		pr_debug("Connection termination");
1172		nfc_dep_link_down(local->dev);
1173		return;
1174	}
1175
1176	llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1177	if (llcp_sock == NULL) {
1178		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1179		return;
1180	}
1181
1182	sk = &llcp_sock->sk;
1183	lock_sock(sk);
1184
1185	nfc_llcp_socket_purge(llcp_sock);
1186
1187	if (sk->sk_state == LLCP_CLOSED) {
1188		release_sock(sk);
1189		nfc_llcp_sock_put(llcp_sock);
1190	}
1191
1192	if (sk->sk_state == LLCP_CONNECTED) {
1193		nfc_put_device(local->dev);
1194		sk->sk_state = LLCP_CLOSED;
1195		sk->sk_state_change(sk);
1196	}
1197
1198	nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_DISC);
1199
1200	release_sock(sk);
1201	nfc_llcp_sock_put(llcp_sock);
1202}
1203
1204static void nfc_llcp_recv_cc(struct nfc_llcp_local *local,
1205			     const struct sk_buff *skb)
1206{
1207	struct nfc_llcp_sock *llcp_sock;
1208	struct sock *sk;
1209	u8 dsap, ssap;
1210
1211	dsap = nfc_llcp_dsap(skb);
1212	ssap = nfc_llcp_ssap(skb);
1213
1214	llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1215	if (llcp_sock == NULL) {
1216		pr_err("Invalid CC\n");
1217		nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1218
1219		return;
1220	}
1221
1222	sk = &llcp_sock->sk;
1223
1224	/* Unlink from connecting and link to the client array */
1225	nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
1226	nfc_llcp_sock_link(&local->sockets, sk);
1227	llcp_sock->dsap = ssap;
1228
1229	nfc_llcp_parse_connection_tlv(llcp_sock, &skb->data[LLCP_HEADER_SIZE],
1230				      skb->len - LLCP_HEADER_SIZE);
1231
1232	sk->sk_state = LLCP_CONNECTED;
1233	sk->sk_state_change(sk);
1234
1235	nfc_llcp_sock_put(llcp_sock);
1236}
1237
1238static void nfc_llcp_recv_dm(struct nfc_llcp_local *local,
1239			     const struct sk_buff *skb)
1240{
1241	struct nfc_llcp_sock *llcp_sock;
1242	struct sock *sk;
1243	u8 dsap, ssap, reason;
1244
1245	dsap = nfc_llcp_dsap(skb);
1246	ssap = nfc_llcp_ssap(skb);
1247	reason = skb->data[2];
1248
1249	pr_debug("%d %d reason %d\n", ssap, dsap, reason);
1250
1251	switch (reason) {
1252	case LLCP_DM_NOBOUND:
1253	case LLCP_DM_REJ:
1254		llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1255		break;
1256
1257	default:
1258		llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1259		break;
1260	}
1261
1262	if (llcp_sock == NULL) {
1263		pr_debug("Already closed\n");
1264		return;
1265	}
1266
1267	sk = &llcp_sock->sk;
1268
1269	sk->sk_err = ENXIO;
1270	sk->sk_state = LLCP_CLOSED;
1271	sk->sk_state_change(sk);
1272
1273	nfc_llcp_sock_put(llcp_sock);
1274}
1275
1276static void nfc_llcp_recv_snl(struct nfc_llcp_local *local,
1277			      const struct sk_buff *skb)
1278{
1279	struct nfc_llcp_sock *llcp_sock;
1280	u8 dsap, ssap, type, length, tid, sap;
1281	const u8 *tlv;
1282	u16 tlv_len, offset;
1283	const char *service_name;
1284	size_t service_name_len;
1285	struct nfc_llcp_sdp_tlv *sdp;
1286	HLIST_HEAD(llc_sdres_list);
1287	size_t sdres_tlvs_len;
1288	HLIST_HEAD(nl_sdres_list);
1289
1290	dsap = nfc_llcp_dsap(skb);
1291	ssap = nfc_llcp_ssap(skb);
1292
1293	pr_debug("%d %d\n", dsap, ssap);
1294
1295	if (dsap != LLCP_SAP_SDP || ssap != LLCP_SAP_SDP) {
1296		pr_err("Wrong SNL SAP\n");
1297		return;
1298	}
1299
1300	tlv = &skb->data[LLCP_HEADER_SIZE];
1301	tlv_len = skb->len - LLCP_HEADER_SIZE;
1302	offset = 0;
1303	sdres_tlvs_len = 0;
1304
1305	while (offset < tlv_len) {
1306		type = tlv[0];
1307		length = tlv[1];
1308
1309		switch (type) {
1310		case LLCP_TLV_SDREQ:
1311			tid = tlv[2];
1312			service_name = (char *) &tlv[3];
1313			service_name_len = length - 1;
1314
1315			pr_debug("Looking for %.16s\n", service_name);
1316
1317			if (service_name_len == strlen("urn:nfc:sn:sdp") &&
1318			    !strncmp(service_name, "urn:nfc:sn:sdp",
1319				     service_name_len)) {
1320				sap = 1;
1321				goto add_snl;
1322			}
1323
1324			llcp_sock = nfc_llcp_sock_from_sn(local, service_name,
1325							  service_name_len,
1326							  true);
1327			if (!llcp_sock) {
1328				sap = 0;
1329				goto add_snl;
1330			}
1331
1332			/*
1333			 * We found a socket but its ssap has not been reserved
1334			 * yet. We need to assign it for good and send a reply.
1335			 * The ssap will be freed when the socket is closed.
1336			 */
1337			if (llcp_sock->ssap == LLCP_SDP_UNBOUND) {
1338				atomic_t *client_count;
1339
1340				sap = nfc_llcp_reserve_sdp_ssap(local);
1341
1342				pr_debug("Reserving %d\n", sap);
1343
1344				if (sap == LLCP_SAP_MAX) {
1345					sap = 0;
1346					nfc_llcp_sock_put(llcp_sock);
1347					goto add_snl;
1348				}
1349
1350				client_count =
1351					&local->local_sdp_cnt[sap -
1352							      LLCP_WKS_NUM_SAP];
1353
1354				atomic_inc(client_count);
1355
1356				llcp_sock->ssap = sap;
1357				llcp_sock->reserved_ssap = sap;
1358			} else {
1359				sap = llcp_sock->ssap;
1360			}
1361
1362			pr_debug("%p %d\n", llcp_sock, sap);
1363
1364			nfc_llcp_sock_put(llcp_sock);
1365add_snl:
1366			sdp = nfc_llcp_build_sdres_tlv(tid, sap);
1367			if (sdp == NULL)
1368				goto exit;
1369
1370			sdres_tlvs_len += sdp->tlv_len;
1371			hlist_add_head(&sdp->node, &llc_sdres_list);
1372			break;
1373
1374		case LLCP_TLV_SDRES:
1375			mutex_lock(&local->sdreq_lock);
1376
1377			pr_debug("LLCP_TLV_SDRES: searching tid %d\n", tlv[2]);
1378
1379			hlist_for_each_entry(sdp, &local->pending_sdreqs, node) {
1380				if (sdp->tid != tlv[2])
1381					continue;
1382
1383				sdp->sap = tlv[3];
1384
1385				pr_debug("Found: uri=%s, sap=%d\n",
1386					 sdp->uri, sdp->sap);
1387
1388				hlist_del(&sdp->node);
1389
1390				hlist_add_head(&sdp->node, &nl_sdres_list);
1391
1392				break;
1393			}
1394
1395			mutex_unlock(&local->sdreq_lock);
1396			break;
1397
1398		default:
1399			pr_err("Invalid SNL tlv value 0x%x\n", type);
1400			break;
1401		}
1402
1403		offset += length + 2;
1404		tlv += length + 2;
1405	}
1406
1407exit:
1408	if (!hlist_empty(&nl_sdres_list))
1409		nfc_genl_llc_send_sdres(local->dev, &nl_sdres_list);
1410
1411	if (!hlist_empty(&llc_sdres_list))
1412		nfc_llcp_send_snl_sdres(local, &llc_sdres_list, sdres_tlvs_len);
1413}
1414
1415static void nfc_llcp_recv_agf(struct nfc_llcp_local *local, struct sk_buff *skb)
1416{
1417	u8 ptype;
1418	u16 pdu_len;
1419	struct sk_buff *new_skb;
1420
1421	if (skb->len <= LLCP_HEADER_SIZE) {
1422		pr_err("Malformed AGF PDU\n");
1423		return;
1424	}
1425
1426	skb_pull(skb, LLCP_HEADER_SIZE);
1427
1428	while (skb->len > LLCP_AGF_PDU_HEADER_SIZE) {
1429		pdu_len = skb->data[0] << 8 | skb->data[1];
1430
1431		skb_pull(skb, LLCP_AGF_PDU_HEADER_SIZE);
1432
1433		if (pdu_len < LLCP_HEADER_SIZE || pdu_len > skb->len) {
1434			pr_err("Malformed AGF PDU\n");
1435			return;
1436		}
1437
1438		ptype = nfc_llcp_ptype(skb);
1439
1440		if (ptype == LLCP_PDU_SYMM || ptype == LLCP_PDU_AGF)
1441			goto next;
1442
1443		new_skb = nfc_alloc_recv_skb(pdu_len, GFP_KERNEL);
1444		if (new_skb == NULL) {
1445			pr_err("Could not allocate PDU\n");
1446			return;
1447		}
1448
1449		skb_put_data(new_skb, skb->data, pdu_len);
1450
1451		nfc_llcp_rx_skb(local, new_skb);
1452
1453		kfree_skb(new_skb);
1454next:
1455		skb_pull(skb, pdu_len);
1456	}
1457}
1458
1459static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb)
1460{
1461	u8 dsap, ssap, ptype;
1462
1463	ptype = nfc_llcp_ptype(skb);
1464	dsap = nfc_llcp_dsap(skb);
1465	ssap = nfc_llcp_ssap(skb);
1466
1467	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
1468
1469	if (ptype != LLCP_PDU_SYMM)
1470		print_hex_dump_debug("LLCP Rx: ", DUMP_PREFIX_OFFSET, 16, 1,
1471				     skb->data, skb->len, true);
1472
1473	switch (ptype) {
1474	case LLCP_PDU_SYMM:
1475		pr_debug("SYMM\n");
1476		break;
1477
1478	case LLCP_PDU_UI:
1479		pr_debug("UI\n");
1480		nfc_llcp_recv_ui(local, skb);
1481		break;
1482
1483	case LLCP_PDU_CONNECT:
1484		pr_debug("CONNECT\n");
1485		nfc_llcp_recv_connect(local, skb);
1486		break;
1487
1488	case LLCP_PDU_DISC:
1489		pr_debug("DISC\n");
1490		nfc_llcp_recv_disc(local, skb);
1491		break;
1492
1493	case LLCP_PDU_CC:
1494		pr_debug("CC\n");
1495		nfc_llcp_recv_cc(local, skb);
1496		break;
1497
1498	case LLCP_PDU_DM:
1499		pr_debug("DM\n");
1500		nfc_llcp_recv_dm(local, skb);
1501		break;
1502
1503	case LLCP_PDU_SNL:
1504		pr_debug("SNL\n");
1505		nfc_llcp_recv_snl(local, skb);
1506		break;
1507
1508	case LLCP_PDU_I:
1509	case LLCP_PDU_RR:
1510	case LLCP_PDU_RNR:
1511		pr_debug("I frame\n");
1512		nfc_llcp_recv_hdlc(local, skb);
1513		break;
1514
1515	case LLCP_PDU_AGF:
1516		pr_debug("AGF frame\n");
1517		nfc_llcp_recv_agf(local, skb);
1518		break;
1519	}
1520}
1521
1522static void nfc_llcp_rx_work(struct work_struct *work)
1523{
1524	struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
1525						    rx_work);
1526	struct sk_buff *skb;
1527
1528	skb = local->rx_pending;
1529	if (skb == NULL) {
1530		pr_debug("No pending SKB\n");
1531		return;
1532	}
1533
1534	__net_timestamp(skb);
1535
1536	nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_RX);
1537
1538	nfc_llcp_rx_skb(local, skb);
1539
1540	schedule_work(&local->tx_work);
1541	kfree_skb(local->rx_pending);
1542	local->rx_pending = NULL;
1543}
1544
1545static void __nfc_llcp_recv(struct nfc_llcp_local *local, struct sk_buff *skb)
1546{
1547	local->rx_pending = skb;
1548	del_timer(&local->link_timer);
1549	schedule_work(&local->rx_work);
1550}
1551
1552void nfc_llcp_recv(void *data, struct sk_buff *skb, int err)
1553{
1554	struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
1555
1556	pr_debug("Received an LLCP PDU\n");
1557	if (err < 0) {
1558		pr_err("err %d\n", err);
1559		return;
1560	}
1561
1562	__nfc_llcp_recv(local, skb);
1563}
1564
1565int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb)
1566{
1567	struct nfc_llcp_local *local;
1568
1569	local = nfc_llcp_find_local(dev);
1570	if (local == NULL) {
1571		kfree_skb(skb);
1572		return -ENODEV;
1573	}
1574
1575	__nfc_llcp_recv(local, skb);
1576
1577	nfc_llcp_local_put(local);
1578
1579	return 0;
1580}
1581
1582void nfc_llcp_mac_is_down(struct nfc_dev *dev)
1583{
1584	struct nfc_llcp_local *local;
1585
1586	local = nfc_llcp_find_local(dev);
1587	if (local == NULL)
1588		return;
1589
1590	local->remote_miu = LLCP_DEFAULT_MIU;
1591	local->remote_lto = LLCP_DEFAULT_LTO;
1592
1593	/* Close and purge all existing sockets */
1594	nfc_llcp_socket_release(local, true, 0);
1595
1596	nfc_llcp_local_put(local);
1597}
1598
1599void nfc_llcp_mac_is_up(struct nfc_dev *dev, u32 target_idx,
1600			u8 comm_mode, u8 rf_mode)
1601{
1602	struct nfc_llcp_local *local;
1603
1604	pr_debug("rf mode %d\n", rf_mode);
1605
1606	local = nfc_llcp_find_local(dev);
1607	if (local == NULL)
1608		return;
1609
1610	local->target_idx = target_idx;
1611	local->comm_mode = comm_mode;
1612	local->rf_mode = rf_mode;
1613
1614	if (rf_mode == NFC_RF_INITIATOR) {
1615		pr_debug("Queueing Tx work\n");
1616
1617		schedule_work(&local->tx_work);
1618	} else {
1619		mod_timer(&local->link_timer,
1620			  jiffies + msecs_to_jiffies(local->remote_lto));
1621	}
1622
1623	nfc_llcp_local_put(local);
1624}
1625
1626int nfc_llcp_register_device(struct nfc_dev *ndev)
1627{
1628	struct nfc_llcp_local *local;
1629
1630	local = kzalloc(sizeof(struct nfc_llcp_local), GFP_KERNEL);
1631	if (local == NULL)
1632		return -ENOMEM;
1633
1634	/* As we are going to initialize local's refcount, we need to get the
1635	 * nfc_dev to avoid UAF, otherwise there is no point in continuing.
1636	 * See nfc_llcp_local_get().
1637	 */
1638	local->dev = nfc_get_device(ndev->idx);
1639	if (!local->dev) {
1640		kfree(local);
1641		return -ENODEV;
1642	}
1643
1644	INIT_LIST_HEAD(&local->list);
1645	kref_init(&local->ref);
1646	mutex_init(&local->sdp_lock);
1647	timer_setup(&local->link_timer, nfc_llcp_symm_timer, 0);
1648
1649	skb_queue_head_init(&local->tx_queue);
1650	INIT_WORK(&local->tx_work, nfc_llcp_tx_work);
1651
1652	local->rx_pending = NULL;
1653	INIT_WORK(&local->rx_work, nfc_llcp_rx_work);
1654
1655	INIT_WORK(&local->timeout_work, nfc_llcp_timeout_work);
1656
1657	rwlock_init(&local->sockets.lock);
1658	rwlock_init(&local->connecting_sockets.lock);
1659	rwlock_init(&local->raw_sockets.lock);
1660
1661	local->lto = 150; /* 1500 ms */
1662	local->rw = LLCP_MAX_RW;
1663	local->miux = cpu_to_be16(LLCP_MAX_MIUX);
1664	local->local_wks = 0x1; /* LLC Link Management */
1665
1666	nfc_llcp_build_gb(local);
1667
1668	local->remote_miu = LLCP_DEFAULT_MIU;
1669	local->remote_lto = LLCP_DEFAULT_LTO;
1670
1671	mutex_init(&local->sdreq_lock);
1672	INIT_HLIST_HEAD(&local->pending_sdreqs);
1673	timer_setup(&local->sdreq_timer, nfc_llcp_sdreq_timer, 0);
1674	INIT_WORK(&local->sdreq_timeout_work, nfc_llcp_sdreq_timeout_work);
1675
1676	spin_lock(&llcp_devices_lock);
1677	list_add(&local->list, &llcp_devices);
1678	spin_unlock(&llcp_devices_lock);
1679
1680	return 0;
1681}
1682
1683void nfc_llcp_unregister_device(struct nfc_dev *dev)
1684{
1685	struct nfc_llcp_local *local = nfc_llcp_remove_local(dev);
1686
1687	if (local == NULL) {
1688		pr_debug("No such device\n");
1689		return;
1690	}
1691
1692	local_cleanup(local);
1693
1694	nfc_llcp_local_put(local);
1695}
1696
1697int __init nfc_llcp_init(void)
1698{
1699	return nfc_llcp_sock_init();
1700}
1701
1702void nfc_llcp_exit(void)
1703{
1704	nfc_llcp_sock_exit();
1705}
1706