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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
21static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb);
22
23void nfc_llcp_sock_link(struct llcp_sock_list *l, struct sock *sk)
24{
25 write_lock(&l->lock);
26 sk_add_node(sk, &l->head);
27 write_unlock(&l->lock);
28}
29
30void nfc_llcp_sock_unlink(struct llcp_sock_list *l, struct sock *sk)
31{
32 write_lock(&l->lock);
33 sk_del_node_init(sk);
34 write_unlock(&l->lock);
35}
36
37void nfc_llcp_socket_remote_param_init(struct nfc_llcp_sock *sock)
38{
39 sock->remote_rw = LLCP_DEFAULT_RW;
40 sock->remote_miu = LLCP_MAX_MIU + 1;
41}
42
43static void nfc_llcp_socket_purge(struct nfc_llcp_sock *sock)
44{
45 struct nfc_llcp_local *local = sock->local;
46 struct sk_buff *s, *tmp;
47
48 pr_debug("%p\n", &sock->sk);
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
146struct nfc_llcp_local *nfc_llcp_local_get(struct nfc_llcp_local *local)
147{
148 kref_get(&local->ref);
149
150 return local;
151}
152
153static void local_cleanup(struct nfc_llcp_local *local)
154{
155 nfc_llcp_socket_release(local, false, ENXIO);
156 del_timer_sync(&local->link_timer);
157 skb_queue_purge(&local->tx_queue);
158 cancel_work_sync(&local->tx_work);
159 cancel_work_sync(&local->rx_work);
160 cancel_work_sync(&local->timeout_work);
161 kfree_skb(local->rx_pending);
162 del_timer_sync(&local->sdreq_timer);
163 cancel_work_sync(&local->sdreq_timeout_work);
164 nfc_llcp_free_sdp_tlv_list(&local->pending_sdreqs);
165}
166
167static void local_release(struct kref *ref)
168{
169 struct nfc_llcp_local *local;
170
171 local = container_of(ref, struct nfc_llcp_local, ref);
172
173 list_del(&local->list);
174 local_cleanup(local);
175 kfree(local);
176}
177
178int nfc_llcp_local_put(struct nfc_llcp_local *local)
179{
180 if (local == NULL)
181 return 0;
182
183 return kref_put(&local->ref, local_release);
184}
185
186static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
187 u8 ssap, u8 dsap)
188{
189 struct sock *sk;
190 struct nfc_llcp_sock *llcp_sock, *tmp_sock;
191
192 pr_debug("ssap dsap %d %d\n", ssap, dsap);
193
194 if (ssap == 0 && dsap == 0)
195 return NULL;
196
197 read_lock(&local->sockets.lock);
198
199 llcp_sock = NULL;
200
201 sk_for_each(sk, &local->sockets.head) {
202 tmp_sock = nfc_llcp_sock(sk);
203
204 if (tmp_sock->ssap == ssap && tmp_sock->dsap == dsap) {
205 llcp_sock = tmp_sock;
206 break;
207 }
208 }
209
210 read_unlock(&local->sockets.lock);
211
212 if (llcp_sock == NULL)
213 return NULL;
214
215 sock_hold(&llcp_sock->sk);
216
217 return llcp_sock;
218}
219
220static void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
221{
222 sock_put(&sock->sk);
223}
224
225static void nfc_llcp_timeout_work(struct work_struct *work)
226{
227 struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
228 timeout_work);
229
230 nfc_dep_link_down(local->dev);
231}
232
233static void nfc_llcp_symm_timer(struct timer_list *t)
234{
235 struct nfc_llcp_local *local = from_timer(local, t, link_timer);
236
237 pr_err("SYMM timeout\n");
238
239 schedule_work(&local->timeout_work);
240}
241
242static void nfc_llcp_sdreq_timeout_work(struct work_struct *work)
243{
244 unsigned long time;
245 HLIST_HEAD(nl_sdres_list);
246 struct hlist_node *n;
247 struct nfc_llcp_sdp_tlv *sdp;
248 struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
249 sdreq_timeout_work);
250
251 mutex_lock(&local->sdreq_lock);
252
253 time = jiffies - msecs_to_jiffies(3 * local->remote_lto);
254
255 hlist_for_each_entry_safe(sdp, n, &local->pending_sdreqs, node) {
256 if (time_after(sdp->time, time))
257 continue;
258
259 sdp->sap = LLCP_SDP_UNBOUND;
260
261 hlist_del(&sdp->node);
262
263 hlist_add_head(&sdp->node, &nl_sdres_list);
264 }
265
266 if (!hlist_empty(&local->pending_sdreqs))
267 mod_timer(&local->sdreq_timer,
268 jiffies + msecs_to_jiffies(3 * local->remote_lto));
269
270 mutex_unlock(&local->sdreq_lock);
271
272 if (!hlist_empty(&nl_sdres_list))
273 nfc_genl_llc_send_sdres(local->dev, &nl_sdres_list);
274}
275
276static void nfc_llcp_sdreq_timer(struct timer_list *t)
277{
278 struct nfc_llcp_local *local = from_timer(local, t, sdreq_timer);
279
280 schedule_work(&local->sdreq_timeout_work);
281}
282
283struct nfc_llcp_local *nfc_llcp_find_local(struct nfc_dev *dev)
284{
285 struct nfc_llcp_local *local;
286
287 list_for_each_entry(local, &llcp_devices, list)
288 if (local->dev == dev)
289 return local;
290
291 pr_debug("No device found\n");
292
293 return NULL;
294}
295
296static char *wks[] = {
297 NULL,
298 NULL, /* SDP */
299 "urn:nfc:sn:ip",
300 "urn:nfc:sn:obex",
301 "urn:nfc:sn:snep",
302};
303
304static int nfc_llcp_wks_sap(char *service_name, size_t service_name_len)
305{
306 int sap, num_wks;
307
308 pr_debug("%s\n", service_name);
309
310 if (service_name == NULL)
311 return -EINVAL;
312
313 num_wks = ARRAY_SIZE(wks);
314
315 for (sap = 0; sap < num_wks; sap++) {
316 if (wks[sap] == NULL)
317 continue;
318
319 if (strncmp(wks[sap], service_name, service_name_len) == 0)
320 return sap;
321 }
322
323 return -EINVAL;
324}
325
326static
327struct nfc_llcp_sock *nfc_llcp_sock_from_sn(struct nfc_llcp_local *local,
328 u8 *sn, size_t sn_len)
329{
330 struct sock *sk;
331 struct nfc_llcp_sock *llcp_sock, *tmp_sock;
332
333 pr_debug("sn %zd %p\n", sn_len, sn);
334
335 if (sn == NULL || sn_len == 0)
336 return NULL;
337
338 read_lock(&local->sockets.lock);
339
340 llcp_sock = NULL;
341
342 sk_for_each(sk, &local->sockets.head) {
343 tmp_sock = nfc_llcp_sock(sk);
344
345 pr_debug("llcp sock %p\n", tmp_sock);
346
347 if (tmp_sock->sk.sk_type == SOCK_STREAM &&
348 tmp_sock->sk.sk_state != LLCP_LISTEN)
349 continue;
350
351 if (tmp_sock->sk.sk_type == SOCK_DGRAM &&
352 tmp_sock->sk.sk_state != LLCP_BOUND)
353 continue;
354
355 if (tmp_sock->service_name == NULL ||
356 tmp_sock->service_name_len == 0)
357 continue;
358
359 if (tmp_sock->service_name_len != sn_len)
360 continue;
361
362 if (memcmp(sn, tmp_sock->service_name, sn_len) == 0) {
363 llcp_sock = tmp_sock;
364 break;
365 }
366 }
367
368 read_unlock(&local->sockets.lock);
369
370 pr_debug("Found llcp sock %p\n", llcp_sock);
371
372 return llcp_sock;
373}
374
375u8 nfc_llcp_get_sdp_ssap(struct nfc_llcp_local *local,
376 struct nfc_llcp_sock *sock)
377{
378 mutex_lock(&local->sdp_lock);
379
380 if (sock->service_name != NULL && sock->service_name_len > 0) {
381 int ssap = nfc_llcp_wks_sap(sock->service_name,
382 sock->service_name_len);
383
384 if (ssap > 0) {
385 pr_debug("WKS %d\n", ssap);
386
387 /* This is a WKS, let's check if it's free */
388 if (local->local_wks & BIT(ssap)) {
389 mutex_unlock(&local->sdp_lock);
390
391 return LLCP_SAP_MAX;
392 }
393
394 set_bit(ssap, &local->local_wks);
395 mutex_unlock(&local->sdp_lock);
396
397 return ssap;
398 }
399
400 /*
401 * Check if there already is a non WKS socket bound
402 * to this service name.
403 */
404 if (nfc_llcp_sock_from_sn(local, sock->service_name,
405 sock->service_name_len) != NULL) {
406 mutex_unlock(&local->sdp_lock);
407
408 return LLCP_SAP_MAX;
409 }
410
411 mutex_unlock(&local->sdp_lock);
412
413 return LLCP_SDP_UNBOUND;
414
415 } else if (sock->ssap != 0 && sock->ssap < LLCP_WKS_NUM_SAP) {
416 if (!test_bit(sock->ssap, &local->local_wks)) {
417 set_bit(sock->ssap, &local->local_wks);
418 mutex_unlock(&local->sdp_lock);
419
420 return sock->ssap;
421 }
422 }
423
424 mutex_unlock(&local->sdp_lock);
425
426 return LLCP_SAP_MAX;
427}
428
429u8 nfc_llcp_get_local_ssap(struct nfc_llcp_local *local)
430{
431 u8 local_ssap;
432
433 mutex_lock(&local->sdp_lock);
434
435 local_ssap = find_first_zero_bit(&local->local_sap, LLCP_LOCAL_NUM_SAP);
436 if (local_ssap == LLCP_LOCAL_NUM_SAP) {
437 mutex_unlock(&local->sdp_lock);
438 return LLCP_SAP_MAX;
439 }
440
441 set_bit(local_ssap, &local->local_sap);
442
443 mutex_unlock(&local->sdp_lock);
444
445 return local_ssap + LLCP_LOCAL_SAP_OFFSET;
446}
447
448void nfc_llcp_put_ssap(struct nfc_llcp_local *local, u8 ssap)
449{
450 u8 local_ssap;
451 unsigned long *sdp;
452
453 if (ssap < LLCP_WKS_NUM_SAP) {
454 local_ssap = ssap;
455 sdp = &local->local_wks;
456 } else if (ssap < LLCP_LOCAL_NUM_SAP) {
457 atomic_t *client_cnt;
458
459 local_ssap = ssap - LLCP_WKS_NUM_SAP;
460 sdp = &local->local_sdp;
461 client_cnt = &local->local_sdp_cnt[local_ssap];
462
463 pr_debug("%d clients\n", atomic_read(client_cnt));
464
465 mutex_lock(&local->sdp_lock);
466
467 if (atomic_dec_and_test(client_cnt)) {
468 struct nfc_llcp_sock *l_sock;
469
470 pr_debug("No more clients for SAP %d\n", ssap);
471
472 clear_bit(local_ssap, sdp);
473
474 /* Find the listening sock and set it back to UNBOUND */
475 l_sock = nfc_llcp_sock_get(local, ssap, LLCP_SAP_SDP);
476 if (l_sock) {
477 l_sock->ssap = LLCP_SDP_UNBOUND;
478 nfc_llcp_sock_put(l_sock);
479 }
480 }
481
482 mutex_unlock(&local->sdp_lock);
483
484 return;
485 } else if (ssap < LLCP_MAX_SAP) {
486 local_ssap = ssap - LLCP_LOCAL_NUM_SAP;
487 sdp = &local->local_sap;
488 } else {
489 return;
490 }
491
492 mutex_lock(&local->sdp_lock);
493
494 clear_bit(local_ssap, sdp);
495
496 mutex_unlock(&local->sdp_lock);
497}
498
499static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
500{
501 u8 ssap;
502
503 mutex_lock(&local->sdp_lock);
504
505 ssap = find_first_zero_bit(&local->local_sdp, LLCP_SDP_NUM_SAP);
506 if (ssap == LLCP_SDP_NUM_SAP) {
507 mutex_unlock(&local->sdp_lock);
508
509 return LLCP_SAP_MAX;
510 }
511
512 pr_debug("SDP ssap %d\n", LLCP_WKS_NUM_SAP + ssap);
513
514 set_bit(ssap, &local->local_sdp);
515
516 mutex_unlock(&local->sdp_lock);
517
518 return LLCP_WKS_NUM_SAP + ssap;
519}
520
521static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
522{
523 u8 *gb_cur, version, version_length;
524 u8 lto_length, wks_length, miux_length;
525 u8 *version_tlv = NULL, *lto_tlv = NULL,
526 *wks_tlv = NULL, *miux_tlv = NULL;
527 __be16 wks = cpu_to_be16(local->local_wks);
528 u8 gb_len = 0;
529 int ret = 0;
530
531 version = LLCP_VERSION_11;
532 version_tlv = nfc_llcp_build_tlv(LLCP_TLV_VERSION, &version,
533 1, &version_length);
534 if (!version_tlv) {
535 ret = -ENOMEM;
536 goto out;
537 }
538 gb_len += version_length;
539
540 lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &local->lto, 1, <o_length);
541 if (!lto_tlv) {
542 ret = -ENOMEM;
543 goto out;
544 }
545 gb_len += lto_length;
546
547 pr_debug("Local wks 0x%lx\n", local->local_wks);
548 wks_tlv = nfc_llcp_build_tlv(LLCP_TLV_WKS, (u8 *)&wks, 2, &wks_length);
549 if (!wks_tlv) {
550 ret = -ENOMEM;
551 goto out;
552 }
553 gb_len += wks_length;
554
555 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
556 &miux_length);
557 if (!miux_tlv) {
558 ret = -ENOMEM;
559 goto out;
560 }
561 gb_len += miux_length;
562
563 gb_len += ARRAY_SIZE(llcp_magic);
564
565 if (gb_len > NFC_MAX_GT_LEN) {
566 ret = -EINVAL;
567 goto out;
568 }
569
570 gb_cur = local->gb;
571
572 memcpy(gb_cur, llcp_magic, ARRAY_SIZE(llcp_magic));
573 gb_cur += ARRAY_SIZE(llcp_magic);
574
575 memcpy(gb_cur, version_tlv, version_length);
576 gb_cur += version_length;
577
578 memcpy(gb_cur, lto_tlv, lto_length);
579 gb_cur += lto_length;
580
581 memcpy(gb_cur, wks_tlv, wks_length);
582 gb_cur += wks_length;
583
584 memcpy(gb_cur, miux_tlv, miux_length);
585 gb_cur += miux_length;
586
587 local->gb_len = gb_len;
588
589out:
590 kfree(version_tlv);
591 kfree(lto_tlv);
592 kfree(wks_tlv);
593 kfree(miux_tlv);
594
595 return ret;
596}
597
598u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len)
599{
600 struct nfc_llcp_local *local;
601
602 local = nfc_llcp_find_local(dev);
603 if (local == NULL) {
604 *general_bytes_len = 0;
605 return NULL;
606 }
607
608 nfc_llcp_build_gb(local);
609
610 *general_bytes_len = local->gb_len;
611
612 return local->gb;
613}
614
615int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len)
616{
617 struct nfc_llcp_local *local;
618
619 if (gb_len < 3 || gb_len > NFC_MAX_GT_LEN)
620 return -EINVAL;
621
622 local = nfc_llcp_find_local(dev);
623 if (local == NULL) {
624 pr_err("No LLCP device\n");
625 return -ENODEV;
626 }
627
628 memset(local->remote_gb, 0, NFC_MAX_GT_LEN);
629 memcpy(local->remote_gb, gb, gb_len);
630 local->remote_gb_len = gb_len;
631
632 if (memcmp(local->remote_gb, llcp_magic, 3)) {
633 pr_err("MAC does not support LLCP\n");
634 return -EINVAL;
635 }
636
637 return nfc_llcp_parse_gb_tlv(local,
638 &local->remote_gb[3],
639 local->remote_gb_len - 3);
640}
641
642static u8 nfc_llcp_dsap(struct sk_buff *pdu)
643{
644 return (pdu->data[0] & 0xfc) >> 2;
645}
646
647static u8 nfc_llcp_ptype(struct sk_buff *pdu)
648{
649 return ((pdu->data[0] & 0x03) << 2) | ((pdu->data[1] & 0xc0) >> 6);
650}
651
652static u8 nfc_llcp_ssap(struct sk_buff *pdu)
653{
654 return pdu->data[1] & 0x3f;
655}
656
657static u8 nfc_llcp_ns(struct sk_buff *pdu)
658{
659 return pdu->data[2] >> 4;
660}
661
662static u8 nfc_llcp_nr(struct sk_buff *pdu)
663{
664 return pdu->data[2] & 0xf;
665}
666
667static void nfc_llcp_set_nrns(struct nfc_llcp_sock *sock, struct sk_buff *pdu)
668{
669 pdu->data[2] = (sock->send_n << 4) | (sock->recv_n);
670 sock->send_n = (sock->send_n + 1) % 16;
671 sock->recv_ack_n = (sock->recv_n - 1) % 16;
672}
673
674void nfc_llcp_send_to_raw_sock(struct nfc_llcp_local *local,
675 struct sk_buff *skb, u8 direction)
676{
677 struct sk_buff *skb_copy = NULL, *nskb;
678 struct sock *sk;
679 u8 *data;
680
681 read_lock(&local->raw_sockets.lock);
682
683 sk_for_each(sk, &local->raw_sockets.head) {
684 if (sk->sk_state != LLCP_BOUND)
685 continue;
686
687 if (skb_copy == NULL) {
688 skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE,
689 GFP_ATOMIC, true);
690
691 if (skb_copy == NULL)
692 continue;
693
694 data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE);
695
696 data[0] = local->dev ? local->dev->idx : 0xFF;
697 data[1] = direction & 0x01;
698 data[1] |= (RAW_PAYLOAD_LLCP << 1);
699 }
700
701 nskb = skb_clone(skb_copy, GFP_ATOMIC);
702 if (!nskb)
703 continue;
704
705 if (sock_queue_rcv_skb(sk, nskb))
706 kfree_skb(nskb);
707 }
708
709 read_unlock(&local->raw_sockets.lock);
710
711 kfree_skb(skb_copy);
712}
713
714static void nfc_llcp_tx_work(struct work_struct *work)
715{
716 struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
717 tx_work);
718 struct sk_buff *skb;
719 struct sock *sk;
720 struct nfc_llcp_sock *llcp_sock;
721
722 skb = skb_dequeue(&local->tx_queue);
723 if (skb != NULL) {
724 sk = skb->sk;
725 llcp_sock = nfc_llcp_sock(sk);
726
727 if (llcp_sock == NULL && nfc_llcp_ptype(skb) == LLCP_PDU_I) {
728 kfree_skb(skb);
729 nfc_llcp_send_symm(local->dev);
730 } else if (llcp_sock && !llcp_sock->remote_ready) {
731 skb_queue_head(&local->tx_queue, skb);
732 nfc_llcp_send_symm(local->dev);
733 } else {
734 struct sk_buff *copy_skb = NULL;
735 u8 ptype = nfc_llcp_ptype(skb);
736 int ret;
737
738 pr_debug("Sending pending skb\n");
739 print_hex_dump_debug("LLCP Tx: ", DUMP_PREFIX_OFFSET,
740 16, 1, skb->data, skb->len, true);
741
742 if (ptype == LLCP_PDU_DISC && sk != NULL &&
743 sk->sk_state == LLCP_DISCONNECTING) {
744 nfc_llcp_sock_unlink(&local->sockets, sk);
745 sock_orphan(sk);
746 sock_put(sk);
747 }
748
749 if (ptype == LLCP_PDU_I)
750 copy_skb = skb_copy(skb, GFP_ATOMIC);
751
752 __net_timestamp(skb);
753
754 nfc_llcp_send_to_raw_sock(local, skb,
755 NFC_DIRECTION_TX);
756
757 ret = nfc_data_exchange(local->dev, local->target_idx,
758 skb, nfc_llcp_recv, local);
759
760 if (ret) {
761 kfree_skb(copy_skb);
762 goto out;
763 }
764
765 if (ptype == LLCP_PDU_I && copy_skb)
766 skb_queue_tail(&llcp_sock->tx_pending_queue,
767 copy_skb);
768 }
769 } else {
770 nfc_llcp_send_symm(local->dev);
771 }
772
773out:
774 mod_timer(&local->link_timer,
775 jiffies + msecs_to_jiffies(2 * local->remote_lto));
776}
777
778static struct nfc_llcp_sock *nfc_llcp_connecting_sock_get(struct nfc_llcp_local *local,
779 u8 ssap)
780{
781 struct sock *sk;
782 struct nfc_llcp_sock *llcp_sock;
783
784 read_lock(&local->connecting_sockets.lock);
785
786 sk_for_each(sk, &local->connecting_sockets.head) {
787 llcp_sock = nfc_llcp_sock(sk);
788
789 if (llcp_sock->ssap == ssap) {
790 sock_hold(&llcp_sock->sk);
791 goto out;
792 }
793 }
794
795 llcp_sock = NULL;
796
797out:
798 read_unlock(&local->connecting_sockets.lock);
799
800 return llcp_sock;
801}
802
803static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
804 u8 *sn, size_t sn_len)
805{
806 struct nfc_llcp_sock *llcp_sock;
807
808 llcp_sock = nfc_llcp_sock_from_sn(local, sn, sn_len);
809
810 if (llcp_sock == NULL)
811 return NULL;
812
813 sock_hold(&llcp_sock->sk);
814
815 return llcp_sock;
816}
817
818static u8 *nfc_llcp_connect_sn(struct sk_buff *skb, size_t *sn_len)
819{
820 u8 *tlv = &skb->data[2], type, length;
821 size_t tlv_array_len = skb->len - LLCP_HEADER_SIZE, offset = 0;
822
823 while (offset < tlv_array_len) {
824 type = tlv[0];
825 length = tlv[1];
826
827 pr_debug("type 0x%x length %d\n", type, length);
828
829 if (type == LLCP_TLV_SN) {
830 *sn_len = length;
831 return &tlv[2];
832 }
833
834 offset += length + 2;
835 tlv += length + 2;
836 }
837
838 return NULL;
839}
840
841static void nfc_llcp_recv_ui(struct nfc_llcp_local *local,
842 struct sk_buff *skb)
843{
844 struct nfc_llcp_sock *llcp_sock;
845 struct nfc_llcp_ui_cb *ui_cb;
846 u8 dsap, ssap;
847
848 dsap = nfc_llcp_dsap(skb);
849 ssap = nfc_llcp_ssap(skb);
850
851 ui_cb = nfc_llcp_ui_skb_cb(skb);
852 ui_cb->dsap = dsap;
853 ui_cb->ssap = ssap;
854
855 pr_debug("%d %d\n", dsap, ssap);
856
857 /* We're looking for a bound socket, not a client one */
858 llcp_sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
859 if (llcp_sock == NULL || llcp_sock->sk.sk_type != SOCK_DGRAM)
860 return;
861
862 /* There is no sequence with UI frames */
863 skb_pull(skb, LLCP_HEADER_SIZE);
864 if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
865 /*
866 * UI frames will be freed from the socket layer, so we
867 * need to keep them alive until someone receives them.
868 */
869 skb_get(skb);
870 } else {
871 pr_err("Receive queue is full\n");
872 }
873
874 nfc_llcp_sock_put(llcp_sock);
875}
876
877static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
878 struct sk_buff *skb)
879{
880 struct sock *new_sk, *parent;
881 struct nfc_llcp_sock *sock, *new_sock;
882 u8 dsap, ssap, reason;
883
884 dsap = nfc_llcp_dsap(skb);
885 ssap = nfc_llcp_ssap(skb);
886
887 pr_debug("%d %d\n", dsap, ssap);
888
889 if (dsap != LLCP_SAP_SDP) {
890 sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
891 if (sock == NULL || sock->sk.sk_state != LLCP_LISTEN) {
892 reason = LLCP_DM_NOBOUND;
893 goto fail;
894 }
895 } else {
896 u8 *sn;
897 size_t sn_len;
898
899 sn = nfc_llcp_connect_sn(skb, &sn_len);
900 if (sn == NULL) {
901 reason = LLCP_DM_NOBOUND;
902 goto fail;
903 }
904
905 pr_debug("Service name length %zu\n", sn_len);
906
907 sock = nfc_llcp_sock_get_sn(local, sn, sn_len);
908 if (sock == NULL) {
909 reason = LLCP_DM_NOBOUND;
910 goto fail;
911 }
912 }
913
914 lock_sock(&sock->sk);
915
916 parent = &sock->sk;
917
918 if (sk_acceptq_is_full(parent)) {
919 reason = LLCP_DM_REJ;
920 release_sock(&sock->sk);
921 sock_put(&sock->sk);
922 goto fail;
923 }
924
925 if (sock->ssap == LLCP_SDP_UNBOUND) {
926 u8 ssap = nfc_llcp_reserve_sdp_ssap(local);
927
928 pr_debug("First client, reserving %d\n", ssap);
929
930 if (ssap == LLCP_SAP_MAX) {
931 reason = LLCP_DM_REJ;
932 release_sock(&sock->sk);
933 sock_put(&sock->sk);
934 goto fail;
935 }
936
937 sock->ssap = ssap;
938 }
939
940 new_sk = nfc_llcp_sock_alloc(NULL, parent->sk_type, GFP_ATOMIC, 0);
941 if (new_sk == NULL) {
942 reason = LLCP_DM_REJ;
943 release_sock(&sock->sk);
944 sock_put(&sock->sk);
945 goto fail;
946 }
947
948 new_sock = nfc_llcp_sock(new_sk);
949 new_sock->dev = local->dev;
950 new_sock->local = nfc_llcp_local_get(local);
951 new_sock->rw = sock->rw;
952 new_sock->miux = sock->miux;
953 new_sock->nfc_protocol = sock->nfc_protocol;
954 new_sock->dsap = ssap;
955 new_sock->target_idx = local->target_idx;
956 new_sock->parent = parent;
957 new_sock->ssap = sock->ssap;
958 if (sock->ssap < LLCP_LOCAL_NUM_SAP && sock->ssap >= LLCP_WKS_NUM_SAP) {
959 atomic_t *client_count;
960
961 pr_debug("reserved_ssap %d for %p\n", sock->ssap, new_sock);
962
963 client_count =
964 &local->local_sdp_cnt[sock->ssap - LLCP_WKS_NUM_SAP];
965
966 atomic_inc(client_count);
967 new_sock->reserved_ssap = sock->ssap;
968 }
969
970 nfc_llcp_parse_connection_tlv(new_sock, &skb->data[LLCP_HEADER_SIZE],
971 skb->len - LLCP_HEADER_SIZE);
972
973 pr_debug("new sock %p sk %p\n", new_sock, &new_sock->sk);
974
975 nfc_llcp_sock_link(&local->sockets, new_sk);
976
977 nfc_llcp_accept_enqueue(&sock->sk, new_sk);
978
979 nfc_get_device(local->dev->idx);
980
981 new_sk->sk_state = LLCP_CONNECTED;
982
983 /* Wake the listening processes */
984 parent->sk_data_ready(parent);
985
986 /* Send CC */
987 nfc_llcp_send_cc(new_sock);
988
989 release_sock(&sock->sk);
990 sock_put(&sock->sk);
991
992 return;
993
994fail:
995 /* Send DM */
996 nfc_llcp_send_dm(local, dsap, ssap, reason);
997}
998
999int nfc_llcp_queue_i_frames(struct nfc_llcp_sock *sock)
1000{
1001 int nr_frames = 0;
1002 struct nfc_llcp_local *local = sock->local;
1003
1004 pr_debug("Remote ready %d tx queue len %d remote rw %d",
1005 sock->remote_ready, skb_queue_len(&sock->tx_pending_queue),
1006 sock->remote_rw);
1007
1008 /* Try to queue some I frames for transmission */
1009 while (sock->remote_ready &&
1010 skb_queue_len(&sock->tx_pending_queue) < sock->remote_rw) {
1011 struct sk_buff *pdu;
1012
1013 pdu = skb_dequeue(&sock->tx_queue);
1014 if (pdu == NULL)
1015 break;
1016
1017 /* Update N(S)/N(R) */
1018 nfc_llcp_set_nrns(sock, pdu);
1019
1020 skb_queue_tail(&local->tx_queue, pdu);
1021 nr_frames++;
1022 }
1023
1024 return nr_frames;
1025}
1026
1027static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local,
1028 struct sk_buff *skb)
1029{
1030 struct nfc_llcp_sock *llcp_sock;
1031 struct sock *sk;
1032 u8 dsap, ssap, ptype, ns, nr;
1033
1034 ptype = nfc_llcp_ptype(skb);
1035 dsap = nfc_llcp_dsap(skb);
1036 ssap = nfc_llcp_ssap(skb);
1037 ns = nfc_llcp_ns(skb);
1038 nr = nfc_llcp_nr(skb);
1039
1040 pr_debug("%d %d R %d S %d\n", dsap, ssap, nr, ns);
1041
1042 llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1043 if (llcp_sock == NULL) {
1044 nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1045 return;
1046 }
1047
1048 sk = &llcp_sock->sk;
1049 lock_sock(sk);
1050 if (sk->sk_state == LLCP_CLOSED) {
1051 release_sock(sk);
1052 nfc_llcp_sock_put(llcp_sock);
1053 }
1054
1055 /* Pass the payload upstream */
1056 if (ptype == LLCP_PDU_I) {
1057 pr_debug("I frame, queueing on %p\n", &llcp_sock->sk);
1058
1059 if (ns == llcp_sock->recv_n)
1060 llcp_sock->recv_n = (llcp_sock->recv_n + 1) % 16;
1061 else
1062 pr_err("Received out of sequence I PDU\n");
1063
1064 skb_pull(skb, LLCP_HEADER_SIZE + LLCP_SEQUENCE_SIZE);
1065 if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
1066 /*
1067 * I frames will be freed from the socket layer, so we
1068 * need to keep them alive until someone receives them.
1069 */
1070 skb_get(skb);
1071 } else {
1072 pr_err("Receive queue is full\n");
1073 }
1074 }
1075
1076 /* Remove skbs from the pending queue */
1077 if (llcp_sock->send_ack_n != nr) {
1078 struct sk_buff *s, *tmp;
1079 u8 n;
1080
1081 llcp_sock->send_ack_n = nr;
1082
1083 /* Remove and free all skbs until ns == nr */
1084 skb_queue_walk_safe(&llcp_sock->tx_pending_queue, s, tmp) {
1085 n = nfc_llcp_ns(s);
1086
1087 skb_unlink(s, &llcp_sock->tx_pending_queue);
1088 kfree_skb(s);
1089
1090 if (n == nr)
1091 break;
1092 }
1093
1094 /* Re-queue the remaining skbs for transmission */
1095 skb_queue_reverse_walk_safe(&llcp_sock->tx_pending_queue,
1096 s, tmp) {
1097 skb_unlink(s, &llcp_sock->tx_pending_queue);
1098 skb_queue_head(&local->tx_queue, s);
1099 }
1100 }
1101
1102 if (ptype == LLCP_PDU_RR)
1103 llcp_sock->remote_ready = true;
1104 else if (ptype == LLCP_PDU_RNR)
1105 llcp_sock->remote_ready = false;
1106
1107 if (nfc_llcp_queue_i_frames(llcp_sock) == 0 && ptype == LLCP_PDU_I)
1108 nfc_llcp_send_rr(llcp_sock);
1109
1110 release_sock(sk);
1111 nfc_llcp_sock_put(llcp_sock);
1112}
1113
1114static void nfc_llcp_recv_disc(struct nfc_llcp_local *local,
1115 struct sk_buff *skb)
1116{
1117 struct nfc_llcp_sock *llcp_sock;
1118 struct sock *sk;
1119 u8 dsap, ssap;
1120
1121 dsap = nfc_llcp_dsap(skb);
1122 ssap = nfc_llcp_ssap(skb);
1123
1124 if ((dsap == 0) && (ssap == 0)) {
1125 pr_debug("Connection termination");
1126 nfc_dep_link_down(local->dev);
1127 return;
1128 }
1129
1130 llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1131 if (llcp_sock == NULL) {
1132 nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1133 return;
1134 }
1135
1136 sk = &llcp_sock->sk;
1137 lock_sock(sk);
1138
1139 nfc_llcp_socket_purge(llcp_sock);
1140
1141 if (sk->sk_state == LLCP_CLOSED) {
1142 release_sock(sk);
1143 nfc_llcp_sock_put(llcp_sock);
1144 }
1145
1146 if (sk->sk_state == LLCP_CONNECTED) {
1147 nfc_put_device(local->dev);
1148 sk->sk_state = LLCP_CLOSED;
1149 sk->sk_state_change(sk);
1150 }
1151
1152 nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_DISC);
1153
1154 release_sock(sk);
1155 nfc_llcp_sock_put(llcp_sock);
1156}
1157
1158static void nfc_llcp_recv_cc(struct nfc_llcp_local *local, struct sk_buff *skb)
1159{
1160 struct nfc_llcp_sock *llcp_sock;
1161 struct sock *sk;
1162 u8 dsap, ssap;
1163
1164 dsap = nfc_llcp_dsap(skb);
1165 ssap = nfc_llcp_ssap(skb);
1166
1167 llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1168 if (llcp_sock == NULL) {
1169 pr_err("Invalid CC\n");
1170 nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
1171
1172 return;
1173 }
1174
1175 sk = &llcp_sock->sk;
1176
1177 /* Unlink from connecting and link to the client array */
1178 nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
1179 nfc_llcp_sock_link(&local->sockets, sk);
1180 llcp_sock->dsap = ssap;
1181
1182 nfc_llcp_parse_connection_tlv(llcp_sock, &skb->data[LLCP_HEADER_SIZE],
1183 skb->len - LLCP_HEADER_SIZE);
1184
1185 sk->sk_state = LLCP_CONNECTED;
1186 sk->sk_state_change(sk);
1187
1188 nfc_llcp_sock_put(llcp_sock);
1189}
1190
1191static void nfc_llcp_recv_dm(struct nfc_llcp_local *local, struct sk_buff *skb)
1192{
1193 struct nfc_llcp_sock *llcp_sock;
1194 struct sock *sk;
1195 u8 dsap, ssap, reason;
1196
1197 dsap = nfc_llcp_dsap(skb);
1198 ssap = nfc_llcp_ssap(skb);
1199 reason = skb->data[2];
1200
1201 pr_debug("%d %d reason %d\n", ssap, dsap, reason);
1202
1203 switch (reason) {
1204 case LLCP_DM_NOBOUND:
1205 case LLCP_DM_REJ:
1206 llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
1207 break;
1208
1209 default:
1210 llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
1211 break;
1212 }
1213
1214 if (llcp_sock == NULL) {
1215 pr_debug("Already closed\n");
1216 return;
1217 }
1218
1219 sk = &llcp_sock->sk;
1220
1221 sk->sk_err = ENXIO;
1222 sk->sk_state = LLCP_CLOSED;
1223 sk->sk_state_change(sk);
1224
1225 nfc_llcp_sock_put(llcp_sock);
1226}
1227
1228static void nfc_llcp_recv_snl(struct nfc_llcp_local *local,
1229 struct sk_buff *skb)
1230{
1231 struct nfc_llcp_sock *llcp_sock;
1232 u8 dsap, ssap, *tlv, type, length, tid, sap;
1233 u16 tlv_len, offset;
1234 char *service_name;
1235 size_t service_name_len;
1236 struct nfc_llcp_sdp_tlv *sdp;
1237 HLIST_HEAD(llc_sdres_list);
1238 size_t sdres_tlvs_len;
1239 HLIST_HEAD(nl_sdres_list);
1240
1241 dsap = nfc_llcp_dsap(skb);
1242 ssap = nfc_llcp_ssap(skb);
1243
1244 pr_debug("%d %d\n", dsap, ssap);
1245
1246 if (dsap != LLCP_SAP_SDP || ssap != LLCP_SAP_SDP) {
1247 pr_err("Wrong SNL SAP\n");
1248 return;
1249 }
1250
1251 tlv = &skb->data[LLCP_HEADER_SIZE];
1252 tlv_len = skb->len - LLCP_HEADER_SIZE;
1253 offset = 0;
1254 sdres_tlvs_len = 0;
1255
1256 while (offset < tlv_len) {
1257 type = tlv[0];
1258 length = tlv[1];
1259
1260 switch (type) {
1261 case LLCP_TLV_SDREQ:
1262 tid = tlv[2];
1263 service_name = (char *) &tlv[3];
1264 service_name_len = length - 1;
1265
1266 pr_debug("Looking for %.16s\n", service_name);
1267
1268 if (service_name_len == strlen("urn:nfc:sn:sdp") &&
1269 !strncmp(service_name, "urn:nfc:sn:sdp",
1270 service_name_len)) {
1271 sap = 1;
1272 goto add_snl;
1273 }
1274
1275 llcp_sock = nfc_llcp_sock_from_sn(local, service_name,
1276 service_name_len);
1277 if (!llcp_sock) {
1278 sap = 0;
1279 goto add_snl;
1280 }
1281
1282 /*
1283 * We found a socket but its ssap has not been reserved
1284 * yet. We need to assign it for good and send a reply.
1285 * The ssap will be freed when the socket is closed.
1286 */
1287 if (llcp_sock->ssap == LLCP_SDP_UNBOUND) {
1288 atomic_t *client_count;
1289
1290 sap = nfc_llcp_reserve_sdp_ssap(local);
1291
1292 pr_debug("Reserving %d\n", sap);
1293
1294 if (sap == LLCP_SAP_MAX) {
1295 sap = 0;
1296 goto add_snl;
1297 }
1298
1299 client_count =
1300 &local->local_sdp_cnt[sap -
1301 LLCP_WKS_NUM_SAP];
1302
1303 atomic_inc(client_count);
1304
1305 llcp_sock->ssap = sap;
1306 llcp_sock->reserved_ssap = sap;
1307 } else {
1308 sap = llcp_sock->ssap;
1309 }
1310
1311 pr_debug("%p %d\n", llcp_sock, sap);
1312
1313add_snl:
1314 sdp = nfc_llcp_build_sdres_tlv(tid, sap);
1315 if (sdp == NULL)
1316 goto exit;
1317
1318 sdres_tlvs_len += sdp->tlv_len;
1319 hlist_add_head(&sdp->node, &llc_sdres_list);
1320 break;
1321
1322 case LLCP_TLV_SDRES:
1323 mutex_lock(&local->sdreq_lock);
1324
1325 pr_debug("LLCP_TLV_SDRES: searching tid %d\n", tlv[2]);
1326
1327 hlist_for_each_entry(sdp, &local->pending_sdreqs, node) {
1328 if (sdp->tid != tlv[2])
1329 continue;
1330
1331 sdp->sap = tlv[3];
1332
1333 pr_debug("Found: uri=%s, sap=%d\n",
1334 sdp->uri, sdp->sap);
1335
1336 hlist_del(&sdp->node);
1337
1338 hlist_add_head(&sdp->node, &nl_sdres_list);
1339
1340 break;
1341 }
1342
1343 mutex_unlock(&local->sdreq_lock);
1344 break;
1345
1346 default:
1347 pr_err("Invalid SNL tlv value 0x%x\n", type);
1348 break;
1349 }
1350
1351 offset += length + 2;
1352 tlv += length + 2;
1353 }
1354
1355exit:
1356 if (!hlist_empty(&nl_sdres_list))
1357 nfc_genl_llc_send_sdres(local->dev, &nl_sdres_list);
1358
1359 if (!hlist_empty(&llc_sdres_list))
1360 nfc_llcp_send_snl_sdres(local, &llc_sdres_list, sdres_tlvs_len);
1361}
1362
1363static void nfc_llcp_recv_agf(struct nfc_llcp_local *local, struct sk_buff *skb)
1364{
1365 u8 ptype;
1366 u16 pdu_len;
1367 struct sk_buff *new_skb;
1368
1369 if (skb->len <= LLCP_HEADER_SIZE) {
1370 pr_err("Malformed AGF PDU\n");
1371 return;
1372 }
1373
1374 skb_pull(skb, LLCP_HEADER_SIZE);
1375
1376 while (skb->len > LLCP_AGF_PDU_HEADER_SIZE) {
1377 pdu_len = skb->data[0] << 8 | skb->data[1];
1378
1379 skb_pull(skb, LLCP_AGF_PDU_HEADER_SIZE);
1380
1381 if (pdu_len < LLCP_HEADER_SIZE || pdu_len > skb->len) {
1382 pr_err("Malformed AGF PDU\n");
1383 return;
1384 }
1385
1386 ptype = nfc_llcp_ptype(skb);
1387
1388 if (ptype == LLCP_PDU_SYMM || ptype == LLCP_PDU_AGF)
1389 goto next;
1390
1391 new_skb = nfc_alloc_recv_skb(pdu_len, GFP_KERNEL);
1392 if (new_skb == NULL) {
1393 pr_err("Could not allocate PDU\n");
1394 return;
1395 }
1396
1397 skb_put_data(new_skb, skb->data, pdu_len);
1398
1399 nfc_llcp_rx_skb(local, new_skb);
1400
1401 kfree_skb(new_skb);
1402next:
1403 skb_pull(skb, pdu_len);
1404 }
1405}
1406
1407static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb)
1408{
1409 u8 dsap, ssap, ptype;
1410
1411 ptype = nfc_llcp_ptype(skb);
1412 dsap = nfc_llcp_dsap(skb);
1413 ssap = nfc_llcp_ssap(skb);
1414
1415 pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
1416
1417 if (ptype != LLCP_PDU_SYMM)
1418 print_hex_dump_debug("LLCP Rx: ", DUMP_PREFIX_OFFSET, 16, 1,
1419 skb->data, skb->len, true);
1420
1421 switch (ptype) {
1422 case LLCP_PDU_SYMM:
1423 pr_debug("SYMM\n");
1424 break;
1425
1426 case LLCP_PDU_UI:
1427 pr_debug("UI\n");
1428 nfc_llcp_recv_ui(local, skb);
1429 break;
1430
1431 case LLCP_PDU_CONNECT:
1432 pr_debug("CONNECT\n");
1433 nfc_llcp_recv_connect(local, skb);
1434 break;
1435
1436 case LLCP_PDU_DISC:
1437 pr_debug("DISC\n");
1438 nfc_llcp_recv_disc(local, skb);
1439 break;
1440
1441 case LLCP_PDU_CC:
1442 pr_debug("CC\n");
1443 nfc_llcp_recv_cc(local, skb);
1444 break;
1445
1446 case LLCP_PDU_DM:
1447 pr_debug("DM\n");
1448 nfc_llcp_recv_dm(local, skb);
1449 break;
1450
1451 case LLCP_PDU_SNL:
1452 pr_debug("SNL\n");
1453 nfc_llcp_recv_snl(local, skb);
1454 break;
1455
1456 case LLCP_PDU_I:
1457 case LLCP_PDU_RR:
1458 case LLCP_PDU_RNR:
1459 pr_debug("I frame\n");
1460 nfc_llcp_recv_hdlc(local, skb);
1461 break;
1462
1463 case LLCP_PDU_AGF:
1464 pr_debug("AGF frame\n");
1465 nfc_llcp_recv_agf(local, skb);
1466 break;
1467 }
1468}
1469
1470static void nfc_llcp_rx_work(struct work_struct *work)
1471{
1472 struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
1473 rx_work);
1474 struct sk_buff *skb;
1475
1476 skb = local->rx_pending;
1477 if (skb == NULL) {
1478 pr_debug("No pending SKB\n");
1479 return;
1480 }
1481
1482 __net_timestamp(skb);
1483
1484 nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_RX);
1485
1486 nfc_llcp_rx_skb(local, skb);
1487
1488 schedule_work(&local->tx_work);
1489 kfree_skb(local->rx_pending);
1490 local->rx_pending = NULL;
1491}
1492
1493static void __nfc_llcp_recv(struct nfc_llcp_local *local, struct sk_buff *skb)
1494{
1495 local->rx_pending = skb;
1496 del_timer(&local->link_timer);
1497 schedule_work(&local->rx_work);
1498}
1499
1500void nfc_llcp_recv(void *data, struct sk_buff *skb, int err)
1501{
1502 struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
1503
1504 pr_debug("Received an LLCP PDU\n");
1505 if (err < 0) {
1506 pr_err("err %d\n", err);
1507 return;
1508 }
1509
1510 __nfc_llcp_recv(local, skb);
1511}
1512
1513int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb)
1514{
1515 struct nfc_llcp_local *local;
1516
1517 local = nfc_llcp_find_local(dev);
1518 if (local == NULL) {
1519 kfree_skb(skb);
1520 return -ENODEV;
1521 }
1522
1523 __nfc_llcp_recv(local, skb);
1524
1525 return 0;
1526}
1527
1528void nfc_llcp_mac_is_down(struct nfc_dev *dev)
1529{
1530 struct nfc_llcp_local *local;
1531
1532 local = nfc_llcp_find_local(dev);
1533 if (local == NULL)
1534 return;
1535
1536 local->remote_miu = LLCP_DEFAULT_MIU;
1537 local->remote_lto = LLCP_DEFAULT_LTO;
1538
1539 /* Close and purge all existing sockets */
1540 nfc_llcp_socket_release(local, true, 0);
1541}
1542
1543void nfc_llcp_mac_is_up(struct nfc_dev *dev, u32 target_idx,
1544 u8 comm_mode, u8 rf_mode)
1545{
1546 struct nfc_llcp_local *local;
1547
1548 pr_debug("rf mode %d\n", rf_mode);
1549
1550 local = nfc_llcp_find_local(dev);
1551 if (local == NULL)
1552 return;
1553
1554 local->target_idx = target_idx;
1555 local->comm_mode = comm_mode;
1556 local->rf_mode = rf_mode;
1557
1558 if (rf_mode == NFC_RF_INITIATOR) {
1559 pr_debug("Queueing Tx work\n");
1560
1561 schedule_work(&local->tx_work);
1562 } else {
1563 mod_timer(&local->link_timer,
1564 jiffies + msecs_to_jiffies(local->remote_lto));
1565 }
1566}
1567
1568int nfc_llcp_register_device(struct nfc_dev *ndev)
1569{
1570 struct nfc_llcp_local *local;
1571
1572 local = kzalloc(sizeof(struct nfc_llcp_local), GFP_KERNEL);
1573 if (local == NULL)
1574 return -ENOMEM;
1575
1576 local->dev = ndev;
1577 INIT_LIST_HEAD(&local->list);
1578 kref_init(&local->ref);
1579 mutex_init(&local->sdp_lock);
1580 timer_setup(&local->link_timer, nfc_llcp_symm_timer, 0);
1581
1582 skb_queue_head_init(&local->tx_queue);
1583 INIT_WORK(&local->tx_work, nfc_llcp_tx_work);
1584
1585 local->rx_pending = NULL;
1586 INIT_WORK(&local->rx_work, nfc_llcp_rx_work);
1587
1588 INIT_WORK(&local->timeout_work, nfc_llcp_timeout_work);
1589
1590 rwlock_init(&local->sockets.lock);
1591 rwlock_init(&local->connecting_sockets.lock);
1592 rwlock_init(&local->raw_sockets.lock);
1593
1594 local->lto = 150; /* 1500 ms */
1595 local->rw = LLCP_MAX_RW;
1596 local->miux = cpu_to_be16(LLCP_MAX_MIUX);
1597 local->local_wks = 0x1; /* LLC Link Management */
1598
1599 nfc_llcp_build_gb(local);
1600
1601 local->remote_miu = LLCP_DEFAULT_MIU;
1602 local->remote_lto = LLCP_DEFAULT_LTO;
1603
1604 mutex_init(&local->sdreq_lock);
1605 INIT_HLIST_HEAD(&local->pending_sdreqs);
1606 timer_setup(&local->sdreq_timer, nfc_llcp_sdreq_timer, 0);
1607 INIT_WORK(&local->sdreq_timeout_work, nfc_llcp_sdreq_timeout_work);
1608
1609 list_add(&local->list, &llcp_devices);
1610
1611 return 0;
1612}
1613
1614void nfc_llcp_unregister_device(struct nfc_dev *dev)
1615{
1616 struct nfc_llcp_local *local = nfc_llcp_find_local(dev);
1617
1618 if (local == NULL) {
1619 pr_debug("No such device\n");
1620 return;
1621 }
1622
1623 local_cleanup(local);
1624
1625 nfc_llcp_local_put(local);
1626}
1627
1628int __init nfc_llcp_init(void)
1629{
1630 return nfc_llcp_sock_init();
1631}
1632
1633void nfc_llcp_exit(void)
1634{
1635 nfc_llcp_sock_exit();
1636}
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, <o_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}