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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2011 Intel Corporation. All rights reserved.
4 */
5
6#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
7
8#include <linux/init.h>
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/nfc.h>
12
13#include <net/nfc/nfc.h>
14
15#include "nfc.h"
16#include "llcp.h"
17
18static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
19 0,
20 1, /* VERSION */
21 2, /* MIUX */
22 2, /* WKS */
23 1, /* LTO */
24 1, /* RW */
25 0, /* SN */
26 1, /* OPT */
27 0, /* SDREQ */
28 2, /* SDRES */
29
30};
31
32static u8 llcp_tlv8(u8 *tlv, u8 type)
33{
34 if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
35 return 0;
36
37 return tlv[2];
38}
39
40static u16 llcp_tlv16(u8 *tlv, u8 type)
41{
42 if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
43 return 0;
44
45 return be16_to_cpu(*((__be16 *)(tlv + 2)));
46}
47
48
49static u8 llcp_tlv_version(u8 *tlv)
50{
51 return llcp_tlv8(tlv, LLCP_TLV_VERSION);
52}
53
54static u16 llcp_tlv_miux(u8 *tlv)
55{
56 return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
57}
58
59static u16 llcp_tlv_wks(u8 *tlv)
60{
61 return llcp_tlv16(tlv, LLCP_TLV_WKS);
62}
63
64static u16 llcp_tlv_lto(u8 *tlv)
65{
66 return llcp_tlv8(tlv, LLCP_TLV_LTO);
67}
68
69static u8 llcp_tlv_opt(u8 *tlv)
70{
71 return llcp_tlv8(tlv, LLCP_TLV_OPT);
72}
73
74static u8 llcp_tlv_rw(u8 *tlv)
75{
76 return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
77}
78
79u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
80{
81 u8 *tlv, length;
82
83 pr_debug("type %d\n", type);
84
85 if (type >= LLCP_TLV_MAX)
86 return NULL;
87
88 length = llcp_tlv_length[type];
89 if (length == 0 && value_length == 0)
90 return NULL;
91 else if (length == 0)
92 length = value_length;
93
94 *tlv_length = 2 + length;
95 tlv = kzalloc(2 + length, GFP_KERNEL);
96 if (tlv == NULL)
97 return tlv;
98
99 tlv[0] = type;
100 tlv[1] = length;
101 memcpy(tlv + 2, value, length);
102
103 return tlv;
104}
105
106struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdres_tlv(u8 tid, u8 sap)
107{
108 struct nfc_llcp_sdp_tlv *sdres;
109 u8 value[2];
110
111 sdres = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
112 if (sdres == NULL)
113 return NULL;
114
115 value[0] = tid;
116 value[1] = sap;
117
118 sdres->tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, value, 2,
119 &sdres->tlv_len);
120 if (sdres->tlv == NULL) {
121 kfree(sdres);
122 return NULL;
123 }
124
125 sdres->tid = tid;
126 sdres->sap = sap;
127
128 INIT_HLIST_NODE(&sdres->node);
129
130 return sdres;
131}
132
133struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, char *uri,
134 size_t uri_len)
135{
136 struct nfc_llcp_sdp_tlv *sdreq;
137
138 pr_debug("uri: %s, len: %zu\n", uri, uri_len);
139
140 /* sdreq->tlv_len is u8, takes uri_len, + 3 for header, + 1 for NULL */
141 if (WARN_ON_ONCE(uri_len > U8_MAX - 4))
142 return NULL;
143
144 sdreq = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
145 if (sdreq == NULL)
146 return NULL;
147
148 sdreq->tlv_len = uri_len + 3;
149
150 if (uri[uri_len - 1] == 0)
151 sdreq->tlv_len--;
152
153 sdreq->tlv = kzalloc(sdreq->tlv_len + 1, GFP_KERNEL);
154 if (sdreq->tlv == NULL) {
155 kfree(sdreq);
156 return NULL;
157 }
158
159 sdreq->tlv[0] = LLCP_TLV_SDREQ;
160 sdreq->tlv[1] = sdreq->tlv_len - 2;
161 sdreq->tlv[2] = tid;
162
163 sdreq->tid = tid;
164 sdreq->uri = sdreq->tlv + 3;
165 memcpy(sdreq->uri, uri, uri_len);
166
167 sdreq->time = jiffies;
168
169 INIT_HLIST_NODE(&sdreq->node);
170
171 return sdreq;
172}
173
174void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
175{
176 kfree(sdp->tlv);
177 kfree(sdp);
178}
179
180void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
181{
182 struct nfc_llcp_sdp_tlv *sdp;
183 struct hlist_node *n;
184
185 hlist_for_each_entry_safe(sdp, n, head, node) {
186 hlist_del(&sdp->node);
187
188 nfc_llcp_free_sdp_tlv(sdp);
189 }
190}
191
192int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
193 u8 *tlv_array, u16 tlv_array_len)
194{
195 u8 *tlv = tlv_array, type, length, offset = 0;
196
197 pr_debug("TLV array length %d\n", tlv_array_len);
198
199 if (local == NULL)
200 return -ENODEV;
201
202 while (offset < tlv_array_len) {
203 type = tlv[0];
204 length = tlv[1];
205
206 pr_debug("type 0x%x length %d\n", type, length);
207
208 switch (type) {
209 case LLCP_TLV_VERSION:
210 local->remote_version = llcp_tlv_version(tlv);
211 break;
212 case LLCP_TLV_MIUX:
213 local->remote_miu = llcp_tlv_miux(tlv) + 128;
214 break;
215 case LLCP_TLV_WKS:
216 local->remote_wks = llcp_tlv_wks(tlv);
217 break;
218 case LLCP_TLV_LTO:
219 local->remote_lto = llcp_tlv_lto(tlv) * 10;
220 break;
221 case LLCP_TLV_OPT:
222 local->remote_opt = llcp_tlv_opt(tlv);
223 break;
224 default:
225 pr_err("Invalid gt tlv value 0x%x\n", type);
226 break;
227 }
228
229 offset += length + 2;
230 tlv += length + 2;
231 }
232
233 pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
234 local->remote_version, local->remote_miu,
235 local->remote_lto, local->remote_opt,
236 local->remote_wks);
237
238 return 0;
239}
240
241int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
242 u8 *tlv_array, u16 tlv_array_len)
243{
244 u8 *tlv = tlv_array, type, length, offset = 0;
245
246 pr_debug("TLV array length %d\n", tlv_array_len);
247
248 if (sock == NULL)
249 return -ENOTCONN;
250
251 while (offset < tlv_array_len) {
252 type = tlv[0];
253 length = tlv[1];
254
255 pr_debug("type 0x%x length %d\n", type, length);
256
257 switch (type) {
258 case LLCP_TLV_MIUX:
259 sock->remote_miu = llcp_tlv_miux(tlv) + 128;
260 break;
261 case LLCP_TLV_RW:
262 sock->remote_rw = llcp_tlv_rw(tlv);
263 break;
264 case LLCP_TLV_SN:
265 break;
266 default:
267 pr_err("Invalid gt tlv value 0x%x\n", type);
268 break;
269 }
270
271 offset += length + 2;
272 tlv += length + 2;
273 }
274
275 pr_debug("sock %p rw %d miu %d\n", sock,
276 sock->remote_rw, sock->remote_miu);
277
278 return 0;
279}
280
281static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
282 u8 dsap, u8 ssap, u8 ptype)
283{
284 u8 header[2];
285
286 pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
287
288 header[0] = (u8)((dsap << 2) | (ptype >> 2));
289 header[1] = (u8)((ptype << 6) | ssap);
290
291 pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
292
293 skb_put_data(pdu, header, LLCP_HEADER_SIZE);
294
295 return pdu;
296}
297
298static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
299 u8 tlv_length)
300{
301 /* XXX Add an skb length check */
302
303 if (tlv == NULL)
304 return NULL;
305
306 skb_put_data(pdu, tlv, tlv_length);
307
308 return pdu;
309}
310
311static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
312 u8 cmd, u16 size)
313{
314 struct sk_buff *skb;
315 int err;
316
317 if (sock->ssap == 0)
318 return NULL;
319
320 skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
321 size + LLCP_HEADER_SIZE, &err);
322 if (skb == NULL) {
323 pr_err("Could not allocate PDU\n");
324 return NULL;
325 }
326
327 skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
328
329 return skb;
330}
331
332int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
333{
334 struct sk_buff *skb;
335 struct nfc_dev *dev;
336 struct nfc_llcp_local *local;
337
338 pr_debug("Sending DISC\n");
339
340 local = sock->local;
341 if (local == NULL)
342 return -ENODEV;
343
344 dev = sock->dev;
345 if (dev == NULL)
346 return -ENODEV;
347
348 skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
349 if (skb == NULL)
350 return -ENOMEM;
351
352 skb_queue_tail(&local->tx_queue, skb);
353
354 return 0;
355}
356
357int nfc_llcp_send_symm(struct nfc_dev *dev)
358{
359 struct sk_buff *skb;
360 struct nfc_llcp_local *local;
361 u16 size = 0;
362
363 pr_debug("Sending SYMM\n");
364
365 local = nfc_llcp_find_local(dev);
366 if (local == NULL)
367 return -ENODEV;
368
369 size += LLCP_HEADER_SIZE;
370 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
371
372 skb = alloc_skb(size, GFP_KERNEL);
373 if (skb == NULL)
374 return -ENOMEM;
375
376 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
377
378 skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
379
380 __net_timestamp(skb);
381
382 nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX);
383
384 return nfc_data_exchange(dev, local->target_idx, skb,
385 nfc_llcp_recv, local);
386}
387
388int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
389{
390 struct nfc_llcp_local *local;
391 struct sk_buff *skb;
392 u8 *service_name_tlv = NULL, service_name_tlv_length;
393 u8 *miux_tlv = NULL, miux_tlv_length;
394 u8 *rw_tlv = NULL, rw_tlv_length, rw;
395 int err;
396 u16 size = 0;
397 __be16 miux;
398
399 pr_debug("Sending CONNECT\n");
400
401 local = sock->local;
402 if (local == NULL)
403 return -ENODEV;
404
405 if (sock->service_name != NULL) {
406 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
407 sock->service_name,
408 sock->service_name_len,
409 &service_name_tlv_length);
410 if (!service_name_tlv) {
411 err = -ENOMEM;
412 goto error_tlv;
413 }
414 size += service_name_tlv_length;
415 }
416
417 /* If the socket parameters are not set, use the local ones */
418 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
419 local->miux : sock->miux;
420 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
421
422 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
423 &miux_tlv_length);
424 if (!miux_tlv) {
425 err = -ENOMEM;
426 goto error_tlv;
427 }
428 size += miux_tlv_length;
429
430 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
431 if (!rw_tlv) {
432 err = -ENOMEM;
433 goto error_tlv;
434 }
435 size += rw_tlv_length;
436
437 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
438
439 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
440 if (skb == NULL) {
441 err = -ENOMEM;
442 goto error_tlv;
443 }
444
445 llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length);
446 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
447 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
448
449 skb_queue_tail(&local->tx_queue, skb);
450
451 err = 0;
452
453error_tlv:
454 if (err)
455 pr_err("error %d\n", err);
456
457 kfree(service_name_tlv);
458 kfree(miux_tlv);
459 kfree(rw_tlv);
460
461 return err;
462}
463
464int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
465{
466 struct nfc_llcp_local *local;
467 struct sk_buff *skb;
468 u8 *miux_tlv = NULL, miux_tlv_length;
469 u8 *rw_tlv = NULL, rw_tlv_length, rw;
470 int err;
471 u16 size = 0;
472 __be16 miux;
473
474 pr_debug("Sending CC\n");
475
476 local = sock->local;
477 if (local == NULL)
478 return -ENODEV;
479
480 /* If the socket parameters are not set, use the local ones */
481 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
482 local->miux : sock->miux;
483 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
484
485 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
486 &miux_tlv_length);
487 if (!miux_tlv) {
488 err = -ENOMEM;
489 goto error_tlv;
490 }
491 size += miux_tlv_length;
492
493 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
494 if (!rw_tlv) {
495 err = -ENOMEM;
496 goto error_tlv;
497 }
498 size += rw_tlv_length;
499
500 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
501 if (skb == NULL) {
502 err = -ENOMEM;
503 goto error_tlv;
504 }
505
506 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
507 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
508
509 skb_queue_tail(&local->tx_queue, skb);
510
511 err = 0;
512
513error_tlv:
514 if (err)
515 pr_err("error %d\n", err);
516
517 kfree(miux_tlv);
518 kfree(rw_tlv);
519
520 return err;
521}
522
523static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
524 size_t tlv_length)
525{
526 struct sk_buff *skb;
527 struct nfc_dev *dev;
528 u16 size = 0;
529
530 if (local == NULL)
531 return ERR_PTR(-ENODEV);
532
533 dev = local->dev;
534 if (dev == NULL)
535 return ERR_PTR(-ENODEV);
536
537 size += LLCP_HEADER_SIZE;
538 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
539 size += tlv_length;
540
541 skb = alloc_skb(size, GFP_KERNEL);
542 if (skb == NULL)
543 return ERR_PTR(-ENOMEM);
544
545 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
546
547 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
548
549 return skb;
550}
551
552int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
553 struct hlist_head *tlv_list, size_t tlvs_len)
554{
555 struct nfc_llcp_sdp_tlv *sdp;
556 struct hlist_node *n;
557 struct sk_buff *skb;
558
559 skb = nfc_llcp_allocate_snl(local, tlvs_len);
560 if (IS_ERR(skb))
561 return PTR_ERR(skb);
562
563 hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
564 skb_put_data(skb, sdp->tlv, sdp->tlv_len);
565
566 hlist_del(&sdp->node);
567
568 nfc_llcp_free_sdp_tlv(sdp);
569 }
570
571 skb_queue_tail(&local->tx_queue, skb);
572
573 return 0;
574}
575
576int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
577 struct hlist_head *tlv_list, size_t tlvs_len)
578{
579 struct nfc_llcp_sdp_tlv *sdreq;
580 struct hlist_node *n;
581 struct sk_buff *skb;
582
583 skb = nfc_llcp_allocate_snl(local, tlvs_len);
584 if (IS_ERR(skb))
585 return PTR_ERR(skb);
586
587 mutex_lock(&local->sdreq_lock);
588
589 if (hlist_empty(&local->pending_sdreqs))
590 mod_timer(&local->sdreq_timer,
591 jiffies + msecs_to_jiffies(3 * local->remote_lto));
592
593 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
594 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
595
596 skb_put_data(skb, sdreq->tlv, sdreq->tlv_len);
597
598 hlist_del(&sdreq->node);
599
600 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
601 }
602
603 mutex_unlock(&local->sdreq_lock);
604
605 skb_queue_tail(&local->tx_queue, skb);
606
607 return 0;
608}
609
610int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
611{
612 struct sk_buff *skb;
613 struct nfc_dev *dev;
614 u16 size = 1; /* Reason code */
615
616 pr_debug("Sending DM reason 0x%x\n", reason);
617
618 if (local == NULL)
619 return -ENODEV;
620
621 dev = local->dev;
622 if (dev == NULL)
623 return -ENODEV;
624
625 size += LLCP_HEADER_SIZE;
626 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
627
628 skb = alloc_skb(size, GFP_KERNEL);
629 if (skb == NULL)
630 return -ENOMEM;
631
632 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
633
634 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
635
636 skb_put_data(skb, &reason, 1);
637
638 skb_queue_head(&local->tx_queue, skb);
639
640 return 0;
641}
642
643int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
644 struct msghdr *msg, size_t len)
645{
646 struct sk_buff *pdu;
647 struct sock *sk = &sock->sk;
648 struct nfc_llcp_local *local;
649 size_t frag_len = 0, remaining_len;
650 u8 *msg_data, *msg_ptr;
651 u16 remote_miu;
652
653 pr_debug("Send I frame len %zd\n", len);
654
655 local = sock->local;
656 if (local == NULL)
657 return -ENODEV;
658
659 /* Remote is ready but has not acknowledged our frames */
660 if((sock->remote_ready &&
661 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
662 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
663 pr_err("Pending queue is full %d frames\n",
664 skb_queue_len(&sock->tx_pending_queue));
665 return -ENOBUFS;
666 }
667
668 /* Remote is not ready and we've been queueing enough frames */
669 if ((!sock->remote_ready &&
670 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
671 pr_err("Tx queue is full %d frames\n",
672 skb_queue_len(&sock->tx_queue));
673 return -ENOBUFS;
674 }
675
676 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
677 if (msg_data == NULL)
678 return -ENOMEM;
679
680 if (memcpy_from_msg(msg_data, msg, len)) {
681 kfree(msg_data);
682 return -EFAULT;
683 }
684
685 remaining_len = len;
686 msg_ptr = msg_data;
687
688 do {
689 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
690 LLCP_DEFAULT_MIU : sock->remote_miu;
691
692 frag_len = min_t(size_t, remote_miu, remaining_len);
693
694 pr_debug("Fragment %zd bytes remaining %zd",
695 frag_len, remaining_len);
696
697 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
698 frag_len + LLCP_SEQUENCE_SIZE);
699 if (pdu == NULL) {
700 kfree(msg_data);
701 return -ENOMEM;
702 }
703
704 skb_put(pdu, LLCP_SEQUENCE_SIZE);
705
706 if (likely(frag_len > 0))
707 skb_put_data(pdu, msg_ptr, frag_len);
708
709 skb_queue_tail(&sock->tx_queue, pdu);
710
711 lock_sock(sk);
712
713 nfc_llcp_queue_i_frames(sock);
714
715 release_sock(sk);
716
717 remaining_len -= frag_len;
718 msg_ptr += frag_len;
719 } while (remaining_len > 0);
720
721 kfree(msg_data);
722
723 return len;
724}
725
726int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
727 struct msghdr *msg, size_t len)
728{
729 struct sk_buff *pdu;
730 struct nfc_llcp_local *local;
731 size_t frag_len = 0, remaining_len;
732 u8 *msg_ptr, *msg_data;
733 u16 remote_miu;
734 int err;
735
736 pr_debug("Send UI frame len %zd\n", len);
737
738 local = sock->local;
739 if (local == NULL)
740 return -ENODEV;
741
742 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
743 if (msg_data == NULL)
744 return -ENOMEM;
745
746 if (memcpy_from_msg(msg_data, msg, len)) {
747 kfree(msg_data);
748 return -EFAULT;
749 }
750
751 remaining_len = len;
752 msg_ptr = msg_data;
753
754 do {
755 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
756 local->remote_miu : sock->remote_miu;
757
758 frag_len = min_t(size_t, remote_miu, remaining_len);
759
760 pr_debug("Fragment %zd bytes remaining %zd",
761 frag_len, remaining_len);
762
763 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, 0,
764 frag_len + LLCP_HEADER_SIZE, &err);
765 if (pdu == NULL) {
766 pr_err("Could not allocate PDU (error=%d)\n", err);
767 len -= remaining_len;
768 if (len == 0)
769 len = err;
770 break;
771 }
772
773 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
774
775 if (likely(frag_len > 0))
776 skb_put_data(pdu, msg_ptr, frag_len);
777
778 /* No need to check for the peer RW for UI frames */
779 skb_queue_tail(&local->tx_queue, pdu);
780
781 remaining_len -= frag_len;
782 msg_ptr += frag_len;
783 } while (remaining_len > 0);
784
785 kfree(msg_data);
786
787 return len;
788}
789
790int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
791{
792 struct sk_buff *skb;
793 struct nfc_llcp_local *local;
794
795 pr_debug("Send rr nr %d\n", sock->recv_n);
796
797 local = sock->local;
798 if (local == NULL)
799 return -ENODEV;
800
801 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
802 if (skb == NULL)
803 return -ENOMEM;
804
805 skb_put(skb, LLCP_SEQUENCE_SIZE);
806
807 skb->data[2] = sock->recv_n;
808
809 skb_queue_head(&local->tx_queue, skb);
810
811 return 0;
812}
1/*
2 * Copyright (C) 2011 Intel Corporation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
16 */
17
18#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
19
20#include <linux/init.h>
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/nfc.h>
24
25#include <net/nfc/nfc.h>
26
27#include "nfc.h"
28#include "llcp.h"
29
30static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
31 0,
32 1, /* VERSION */
33 2, /* MIUX */
34 2, /* WKS */
35 1, /* LTO */
36 1, /* RW */
37 0, /* SN */
38 1, /* OPT */
39 0, /* SDREQ */
40 2, /* SDRES */
41
42};
43
44static u8 llcp_tlv8(u8 *tlv, u8 type)
45{
46 if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
47 return 0;
48
49 return tlv[2];
50}
51
52static u16 llcp_tlv16(u8 *tlv, u8 type)
53{
54 if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
55 return 0;
56
57 return be16_to_cpu(*((__be16 *)(tlv + 2)));
58}
59
60
61static u8 llcp_tlv_version(u8 *tlv)
62{
63 return llcp_tlv8(tlv, LLCP_TLV_VERSION);
64}
65
66static u16 llcp_tlv_miux(u8 *tlv)
67{
68 return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
69}
70
71static u16 llcp_tlv_wks(u8 *tlv)
72{
73 return llcp_tlv16(tlv, LLCP_TLV_WKS);
74}
75
76static u16 llcp_tlv_lto(u8 *tlv)
77{
78 return llcp_tlv8(tlv, LLCP_TLV_LTO);
79}
80
81static u8 llcp_tlv_opt(u8 *tlv)
82{
83 return llcp_tlv8(tlv, LLCP_TLV_OPT);
84}
85
86static u8 llcp_tlv_rw(u8 *tlv)
87{
88 return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
89}
90
91u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
92{
93 u8 *tlv, length;
94
95 pr_debug("type %d\n", type);
96
97 if (type >= LLCP_TLV_MAX)
98 return NULL;
99
100 length = llcp_tlv_length[type];
101 if (length == 0 && value_length == 0)
102 return NULL;
103 else if (length == 0)
104 length = value_length;
105
106 *tlv_length = 2 + length;
107 tlv = kzalloc(2 + length, GFP_KERNEL);
108 if (tlv == NULL)
109 return tlv;
110
111 tlv[0] = type;
112 tlv[1] = length;
113 memcpy(tlv + 2, value, length);
114
115 return tlv;
116}
117
118struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdres_tlv(u8 tid, u8 sap)
119{
120 struct nfc_llcp_sdp_tlv *sdres;
121 u8 value[2];
122
123 sdres = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
124 if (sdres == NULL)
125 return NULL;
126
127 value[0] = tid;
128 value[1] = sap;
129
130 sdres->tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, value, 2,
131 &sdres->tlv_len);
132 if (sdres->tlv == NULL) {
133 kfree(sdres);
134 return NULL;
135 }
136
137 sdres->tid = tid;
138 sdres->sap = sap;
139
140 INIT_HLIST_NODE(&sdres->node);
141
142 return sdres;
143}
144
145struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, char *uri,
146 size_t uri_len)
147{
148 struct nfc_llcp_sdp_tlv *sdreq;
149
150 pr_debug("uri: %s, len: %zu\n", uri, uri_len);
151
152 /* sdreq->tlv_len is u8, takes uri_len, + 3 for header, + 1 for NULL */
153 if (WARN_ON_ONCE(uri_len > U8_MAX - 4))
154 return NULL;
155
156 sdreq = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
157 if (sdreq == NULL)
158 return NULL;
159
160 sdreq->tlv_len = uri_len + 3;
161
162 if (uri[uri_len - 1] == 0)
163 sdreq->tlv_len--;
164
165 sdreq->tlv = kzalloc(sdreq->tlv_len + 1, GFP_KERNEL);
166 if (sdreq->tlv == NULL) {
167 kfree(sdreq);
168 return NULL;
169 }
170
171 sdreq->tlv[0] = LLCP_TLV_SDREQ;
172 sdreq->tlv[1] = sdreq->tlv_len - 2;
173 sdreq->tlv[2] = tid;
174
175 sdreq->tid = tid;
176 sdreq->uri = sdreq->tlv + 3;
177 memcpy(sdreq->uri, uri, uri_len);
178
179 sdreq->time = jiffies;
180
181 INIT_HLIST_NODE(&sdreq->node);
182
183 return sdreq;
184}
185
186void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
187{
188 kfree(sdp->tlv);
189 kfree(sdp);
190}
191
192void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
193{
194 struct nfc_llcp_sdp_tlv *sdp;
195 struct hlist_node *n;
196
197 hlist_for_each_entry_safe(sdp, n, head, node) {
198 hlist_del(&sdp->node);
199
200 nfc_llcp_free_sdp_tlv(sdp);
201 }
202}
203
204int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
205 u8 *tlv_array, u16 tlv_array_len)
206{
207 u8 *tlv = tlv_array, type, length, offset = 0;
208
209 pr_debug("TLV array length %d\n", tlv_array_len);
210
211 if (local == NULL)
212 return -ENODEV;
213
214 while (offset < tlv_array_len) {
215 type = tlv[0];
216 length = tlv[1];
217
218 pr_debug("type 0x%x length %d\n", type, length);
219
220 switch (type) {
221 case LLCP_TLV_VERSION:
222 local->remote_version = llcp_tlv_version(tlv);
223 break;
224 case LLCP_TLV_MIUX:
225 local->remote_miu = llcp_tlv_miux(tlv) + 128;
226 break;
227 case LLCP_TLV_WKS:
228 local->remote_wks = llcp_tlv_wks(tlv);
229 break;
230 case LLCP_TLV_LTO:
231 local->remote_lto = llcp_tlv_lto(tlv) * 10;
232 break;
233 case LLCP_TLV_OPT:
234 local->remote_opt = llcp_tlv_opt(tlv);
235 break;
236 default:
237 pr_err("Invalid gt tlv value 0x%x\n", type);
238 break;
239 }
240
241 offset += length + 2;
242 tlv += length + 2;
243 }
244
245 pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
246 local->remote_version, local->remote_miu,
247 local->remote_lto, local->remote_opt,
248 local->remote_wks);
249
250 return 0;
251}
252
253int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
254 u8 *tlv_array, u16 tlv_array_len)
255{
256 u8 *tlv = tlv_array, type, length, offset = 0;
257
258 pr_debug("TLV array length %d\n", tlv_array_len);
259
260 if (sock == NULL)
261 return -ENOTCONN;
262
263 while (offset < tlv_array_len) {
264 type = tlv[0];
265 length = tlv[1];
266
267 pr_debug("type 0x%x length %d\n", type, length);
268
269 switch (type) {
270 case LLCP_TLV_MIUX:
271 sock->remote_miu = llcp_tlv_miux(tlv) + 128;
272 break;
273 case LLCP_TLV_RW:
274 sock->remote_rw = llcp_tlv_rw(tlv);
275 break;
276 case LLCP_TLV_SN:
277 break;
278 default:
279 pr_err("Invalid gt tlv value 0x%x\n", type);
280 break;
281 }
282
283 offset += length + 2;
284 tlv += length + 2;
285 }
286
287 pr_debug("sock %p rw %d miu %d\n", sock,
288 sock->remote_rw, sock->remote_miu);
289
290 return 0;
291}
292
293static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
294 u8 dsap, u8 ssap, u8 ptype)
295{
296 u8 header[2];
297
298 pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
299
300 header[0] = (u8)((dsap << 2) | (ptype >> 2));
301 header[1] = (u8)((ptype << 6) | ssap);
302
303 pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
304
305 skb_put_data(pdu, header, LLCP_HEADER_SIZE);
306
307 return pdu;
308}
309
310static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
311 u8 tlv_length)
312{
313 /* XXX Add an skb length check */
314
315 if (tlv == NULL)
316 return NULL;
317
318 skb_put_data(pdu, tlv, tlv_length);
319
320 return pdu;
321}
322
323static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
324 u8 cmd, u16 size)
325{
326 struct sk_buff *skb;
327 int err;
328
329 if (sock->ssap == 0)
330 return NULL;
331
332 skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
333 size + LLCP_HEADER_SIZE, &err);
334 if (skb == NULL) {
335 pr_err("Could not allocate PDU\n");
336 return NULL;
337 }
338
339 skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
340
341 return skb;
342}
343
344int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
345{
346 struct sk_buff *skb;
347 struct nfc_dev *dev;
348 struct nfc_llcp_local *local;
349
350 pr_debug("Sending DISC\n");
351
352 local = sock->local;
353 if (local == NULL)
354 return -ENODEV;
355
356 dev = sock->dev;
357 if (dev == NULL)
358 return -ENODEV;
359
360 skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
361 if (skb == NULL)
362 return -ENOMEM;
363
364 skb_queue_tail(&local->tx_queue, skb);
365
366 return 0;
367}
368
369int nfc_llcp_send_symm(struct nfc_dev *dev)
370{
371 struct sk_buff *skb;
372 struct nfc_llcp_local *local;
373 u16 size = 0;
374
375 pr_debug("Sending SYMM\n");
376
377 local = nfc_llcp_find_local(dev);
378 if (local == NULL)
379 return -ENODEV;
380
381 size += LLCP_HEADER_SIZE;
382 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
383
384 skb = alloc_skb(size, GFP_KERNEL);
385 if (skb == NULL)
386 return -ENOMEM;
387
388 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
389
390 skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
391
392 __net_timestamp(skb);
393
394 nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX);
395
396 return nfc_data_exchange(dev, local->target_idx, skb,
397 nfc_llcp_recv, local);
398}
399
400int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
401{
402 struct nfc_llcp_local *local;
403 struct sk_buff *skb;
404 u8 *service_name_tlv = NULL, service_name_tlv_length;
405 u8 *miux_tlv = NULL, miux_tlv_length;
406 u8 *rw_tlv = NULL, rw_tlv_length, rw;
407 int err;
408 u16 size = 0;
409 __be16 miux;
410
411 pr_debug("Sending CONNECT\n");
412
413 local = sock->local;
414 if (local == NULL)
415 return -ENODEV;
416
417 if (sock->service_name != NULL) {
418 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
419 sock->service_name,
420 sock->service_name_len,
421 &service_name_tlv_length);
422 size += service_name_tlv_length;
423 }
424
425 /* If the socket parameters are not set, use the local ones */
426 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
427 local->miux : sock->miux;
428 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
429
430 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
431 &miux_tlv_length);
432 size += miux_tlv_length;
433
434 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
435 size += rw_tlv_length;
436
437 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
438
439 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
440 if (skb == NULL) {
441 err = -ENOMEM;
442 goto error_tlv;
443 }
444
445 llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length);
446 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
447 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
448
449 skb_queue_tail(&local->tx_queue, skb);
450
451 err = 0;
452
453error_tlv:
454 if (err)
455 pr_err("error %d\n", err);
456
457 kfree(service_name_tlv);
458 kfree(miux_tlv);
459 kfree(rw_tlv);
460
461 return err;
462}
463
464int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
465{
466 struct nfc_llcp_local *local;
467 struct sk_buff *skb;
468 u8 *miux_tlv = NULL, miux_tlv_length;
469 u8 *rw_tlv = NULL, rw_tlv_length, rw;
470 int err;
471 u16 size = 0;
472 __be16 miux;
473
474 pr_debug("Sending CC\n");
475
476 local = sock->local;
477 if (local == NULL)
478 return -ENODEV;
479
480 /* If the socket parameters are not set, use the local ones */
481 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
482 local->miux : sock->miux;
483 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
484
485 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
486 &miux_tlv_length);
487 size += miux_tlv_length;
488
489 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
490 size += rw_tlv_length;
491
492 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
493 if (skb == NULL) {
494 err = -ENOMEM;
495 goto error_tlv;
496 }
497
498 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
499 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
500
501 skb_queue_tail(&local->tx_queue, skb);
502
503 err = 0;
504
505error_tlv:
506 if (err)
507 pr_err("error %d\n", err);
508
509 kfree(miux_tlv);
510 kfree(rw_tlv);
511
512 return err;
513}
514
515static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
516 size_t tlv_length)
517{
518 struct sk_buff *skb;
519 struct nfc_dev *dev;
520 u16 size = 0;
521
522 if (local == NULL)
523 return ERR_PTR(-ENODEV);
524
525 dev = local->dev;
526 if (dev == NULL)
527 return ERR_PTR(-ENODEV);
528
529 size += LLCP_HEADER_SIZE;
530 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
531 size += tlv_length;
532
533 skb = alloc_skb(size, GFP_KERNEL);
534 if (skb == NULL)
535 return ERR_PTR(-ENOMEM);
536
537 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
538
539 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
540
541 return skb;
542}
543
544int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
545 struct hlist_head *tlv_list, size_t tlvs_len)
546{
547 struct nfc_llcp_sdp_tlv *sdp;
548 struct hlist_node *n;
549 struct sk_buff *skb;
550
551 skb = nfc_llcp_allocate_snl(local, tlvs_len);
552 if (IS_ERR(skb))
553 return PTR_ERR(skb);
554
555 hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
556 skb_put_data(skb, sdp->tlv, sdp->tlv_len);
557
558 hlist_del(&sdp->node);
559
560 nfc_llcp_free_sdp_tlv(sdp);
561 }
562
563 skb_queue_tail(&local->tx_queue, skb);
564
565 return 0;
566}
567
568int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
569 struct hlist_head *tlv_list, size_t tlvs_len)
570{
571 struct nfc_llcp_sdp_tlv *sdreq;
572 struct hlist_node *n;
573 struct sk_buff *skb;
574
575 skb = nfc_llcp_allocate_snl(local, tlvs_len);
576 if (IS_ERR(skb))
577 return PTR_ERR(skb);
578
579 mutex_lock(&local->sdreq_lock);
580
581 if (hlist_empty(&local->pending_sdreqs))
582 mod_timer(&local->sdreq_timer,
583 jiffies + msecs_to_jiffies(3 * local->remote_lto));
584
585 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
586 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
587
588 skb_put_data(skb, sdreq->tlv, sdreq->tlv_len);
589
590 hlist_del(&sdreq->node);
591
592 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
593 }
594
595 mutex_unlock(&local->sdreq_lock);
596
597 skb_queue_tail(&local->tx_queue, skb);
598
599 return 0;
600}
601
602int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
603{
604 struct sk_buff *skb;
605 struct nfc_dev *dev;
606 u16 size = 1; /* Reason code */
607
608 pr_debug("Sending DM reason 0x%x\n", reason);
609
610 if (local == NULL)
611 return -ENODEV;
612
613 dev = local->dev;
614 if (dev == NULL)
615 return -ENODEV;
616
617 size += LLCP_HEADER_SIZE;
618 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
619
620 skb = alloc_skb(size, GFP_KERNEL);
621 if (skb == NULL)
622 return -ENOMEM;
623
624 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
625
626 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
627
628 skb_put_data(skb, &reason, 1);
629
630 skb_queue_head(&local->tx_queue, skb);
631
632 return 0;
633}
634
635int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
636 struct msghdr *msg, size_t len)
637{
638 struct sk_buff *pdu;
639 struct sock *sk = &sock->sk;
640 struct nfc_llcp_local *local;
641 size_t frag_len = 0, remaining_len;
642 u8 *msg_data, *msg_ptr;
643 u16 remote_miu;
644
645 pr_debug("Send I frame len %zd\n", len);
646
647 local = sock->local;
648 if (local == NULL)
649 return -ENODEV;
650
651 /* Remote is ready but has not acknowledged our frames */
652 if((sock->remote_ready &&
653 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
654 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
655 pr_err("Pending queue is full %d frames\n",
656 skb_queue_len(&sock->tx_pending_queue));
657 return -ENOBUFS;
658 }
659
660 /* Remote is not ready and we've been queueing enough frames */
661 if ((!sock->remote_ready &&
662 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
663 pr_err("Tx queue is full %d frames\n",
664 skb_queue_len(&sock->tx_queue));
665 return -ENOBUFS;
666 }
667
668 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
669 if (msg_data == NULL)
670 return -ENOMEM;
671
672 if (memcpy_from_msg(msg_data, msg, len)) {
673 kfree(msg_data);
674 return -EFAULT;
675 }
676
677 remaining_len = len;
678 msg_ptr = msg_data;
679
680 do {
681 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
682 LLCP_DEFAULT_MIU : sock->remote_miu;
683
684 frag_len = min_t(size_t, remote_miu, remaining_len);
685
686 pr_debug("Fragment %zd bytes remaining %zd",
687 frag_len, remaining_len);
688
689 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
690 frag_len + LLCP_SEQUENCE_SIZE);
691 if (pdu == NULL) {
692 kfree(msg_data);
693 return -ENOMEM;
694 }
695
696 skb_put(pdu, LLCP_SEQUENCE_SIZE);
697
698 if (likely(frag_len > 0))
699 skb_put_data(pdu, msg_ptr, frag_len);
700
701 skb_queue_tail(&sock->tx_queue, pdu);
702
703 lock_sock(sk);
704
705 nfc_llcp_queue_i_frames(sock);
706
707 release_sock(sk);
708
709 remaining_len -= frag_len;
710 msg_ptr += frag_len;
711 } while (remaining_len > 0);
712
713 kfree(msg_data);
714
715 return len;
716}
717
718int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
719 struct msghdr *msg, size_t len)
720{
721 struct sk_buff *pdu;
722 struct nfc_llcp_local *local;
723 size_t frag_len = 0, remaining_len;
724 u8 *msg_ptr, *msg_data;
725 u16 remote_miu;
726 int err;
727
728 pr_debug("Send UI frame len %zd\n", len);
729
730 local = sock->local;
731 if (local == NULL)
732 return -ENODEV;
733
734 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
735 if (msg_data == NULL)
736 return -ENOMEM;
737
738 if (memcpy_from_msg(msg_data, msg, len)) {
739 kfree(msg_data);
740 return -EFAULT;
741 }
742
743 remaining_len = len;
744 msg_ptr = msg_data;
745
746 do {
747 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
748 local->remote_miu : sock->remote_miu;
749
750 frag_len = min_t(size_t, remote_miu, remaining_len);
751
752 pr_debug("Fragment %zd bytes remaining %zd",
753 frag_len, remaining_len);
754
755 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
756 frag_len + LLCP_HEADER_SIZE, &err);
757 if (pdu == NULL) {
758 pr_err("Could not allocate PDU\n");
759 continue;
760 }
761
762 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
763
764 if (likely(frag_len > 0))
765 skb_put_data(pdu, msg_ptr, frag_len);
766
767 /* No need to check for the peer RW for UI frames */
768 skb_queue_tail(&local->tx_queue, pdu);
769
770 remaining_len -= frag_len;
771 msg_ptr += frag_len;
772 } while (remaining_len > 0);
773
774 kfree(msg_data);
775
776 return len;
777}
778
779int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
780{
781 struct sk_buff *skb;
782 struct nfc_llcp_local *local;
783
784 pr_debug("Send rr nr %d\n", sock->recv_n);
785
786 local = sock->local;
787 if (local == NULL)
788 return -ENODEV;
789
790 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
791 if (skb == NULL)
792 return -ENOMEM;
793
794 skb_put(skb, LLCP_SEQUENCE_SIZE);
795
796 skb->data[2] = sock->recv_n;
797
798 skb_queue_head(&local->tx_queue, skb);
799
800 return 0;
801}