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Merge tag 'hwmon-for-v6.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux.git] / net / nfc / llcp_core.c
blob18be13fb9b75a3b06fa25308afa5d71f06d4327a
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
17 static u8 llcp_magic[3] = {0x46, 0x66, 0x6d};
18
19 static LIST_HEAD(llcp_devices);
20 /* Protects llcp_devices list */
21 static DEFINE_SPINLOCK(llcp_devices_lock);
22
23 static void nfc_llcp_rx_skb(struct nfc_llcp_local *local, struct sk_buff *skb);
24
25 void 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
32 void 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
39 void 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
45 static 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
66 static 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
146 static 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
160 static 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
175 static 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
185 int 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
201 static 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
231 static void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
232 {
233 sock_put(&sock->sk);
234 }
235
236 static 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
244 static 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
253 static 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
287 static 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
294 struct 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
310 static 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
328 static char *wks[] = {
329 NULL,
330 NULL, /* SDP */
331 "urn:nfc:sn:ip",
332 "urn:nfc:sn:obex",
333 "urn:nfc:sn:snep",
334 };
335
336 static 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
358 static
359 struct 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
410 u8 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
465 u8 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
484 void 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
535 static 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
557 static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
558 {
559 u8 *gb_cur, version, version_length;
560 u8 lto_length, wks_length, miux_length;
561 const u8 *version_tlv = NULL, *lto_tlv = NULL,
562 *wks_tlv = NULL, *miux_tlv = NULL;
563 __be16 wks = cpu_to_be16(local->local_wks);
564 u8 gb_len = 0;
565 int ret = 0;
566
567 version = LLCP_VERSION_11;
568 version_tlv = nfc_llcp_build_tlv(LLCP_TLV_VERSION, &version,
569 1, &version_length);
570 if (!version_tlv) {
571 ret = -ENOMEM;
572 goto out;
573 }
574 gb_len += version_length;
575
576 lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &local->lto, 1, &lto_length);
577 if (!lto_tlv) {
578 ret = -ENOMEM;
579 goto out;
580 }
581 gb_len += lto_length;
582
583 pr_debug("Local wks 0x%lx\n", local->local_wks);
584 wks_tlv = nfc_llcp_build_tlv(LLCP_TLV_WKS, (u8 *)&wks, 2, &wks_length);
585 if (!wks_tlv) {
586 ret = -ENOMEM;
587 goto out;
588 }
589 gb_len += wks_length;
590
591 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
592 &miux_length);
593 if (!miux_tlv) {
594 ret = -ENOMEM;
595 goto out;
596 }
597 gb_len += miux_length;
598
599 gb_len += ARRAY_SIZE(llcp_magic);
600
601 if (gb_len > NFC_MAX_GT_LEN) {
602 ret = -EINVAL;
603 goto out;
604 }
605
606 gb_cur = local->gb;
607
608 memcpy(gb_cur, llcp_magic, ARRAY_SIZE(llcp_magic));
609 gb_cur += ARRAY_SIZE(llcp_magic);
610
611 memcpy(gb_cur, version_tlv, version_length);
612 gb_cur += version_length;
613
614 memcpy(gb_cur, lto_tlv, lto_length);
615 gb_cur += lto_length;
616
617 memcpy(gb_cur, wks_tlv, wks_length);
618 gb_cur += wks_length;
619
620 memcpy(gb_cur, miux_tlv, miux_length);
621 gb_cur += miux_length;
622
623 local->gb_len = gb_len;
624
625 out:
626 kfree(version_tlv);
627 kfree(lto_tlv);
628 kfree(wks_tlv);
629 kfree(miux_tlv);
630
631 return ret;
632 }
633
634 u8 *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
653 int 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);
680 out:
681 nfc_llcp_local_put(local);
682 return err;
683 }
684
685 static u8 nfc_llcp_dsap(const struct sk_buff *pdu)
686 {
687 return (pdu->data[0] & 0xfc) >> 2;
688 }
689
690 static u8 nfc_llcp_ptype(const struct sk_buff *pdu)
691 {
692 return ((pdu->data[0] & 0x03) << 2) | ((pdu->data[1] & 0xc0) >> 6);
693 }
694
695 static u8 nfc_llcp_ssap(const struct sk_buff *pdu)
696 {
697 return pdu->data[1] & 0x3f;
698 }
699
700 static u8 nfc_llcp_ns(const struct sk_buff *pdu)
701 {
702 return pdu->data[2] >> 4;
703 }
704
705 static u8 nfc_llcp_nr(const struct sk_buff *pdu)
706 {
707 return pdu->data[2] & 0xf;
708 }
709
710 static 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
717 void 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
757 static 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
809 out:
810 mod_timer(&local->link_timer,
811 jiffies + msecs_to_jiffies(2 * local->remote_lto));
812 }
813
814 static 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
833 out:
834 read_unlock(&local->connecting_sockets.lock);
835
836 return llcp_sock;
837 }
838
839 static 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
845 static 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
869 static 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
905 static 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
1031 fail:
1032 /* Send DM */
1033 nfc_llcp_send_dm(local, dsap, ssap, reason);
1034 }
1035
1036 int 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
1064 static 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
1151 static 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
1195 static 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
1229 static 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
1267 static 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);
1356 add_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
1398 exit:
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
1406 static 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);
1445 next:
1446 skb_pull(skb, pdu_len);
1447 }
1448 }
1449
1450 static 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
1513 static 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
1536 static 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
1543 void 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
1555 int 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
1572 void 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
1589 void 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
1616 int 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
1673 void 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
1687 int __init nfc_llcp_init(void)
1688 {
1689 return nfc_llcp_sock_init();
1690 }
1691
1692 void nfc_llcp_exit(void)
1693 {
1694 nfc_llcp_sock_exit();
1695 }
Linux Kernel