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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 = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
153 if (sdreq == NULL)
154 return NULL;
155
156 sdreq->tlv_len = uri_len + 3;
157
158 if (uri[uri_len - 1] == 0)
159 sdreq->tlv_len--;
160
161 sdreq->tlv = kzalloc(sdreq->tlv_len + 1, GFP_KERNEL);
162 if (sdreq->tlv == NULL) {
163 kfree(sdreq);
164 return NULL;
165 }
166
167 sdreq->tlv[0] = LLCP_TLV_SDREQ;
168 sdreq->tlv[1] = sdreq->tlv_len - 2;
169 sdreq->tlv[2] = tid;
170
171 sdreq->tid = tid;
172 sdreq->uri = sdreq->tlv + 3;
173 memcpy(sdreq->uri, uri, uri_len);
174
175 sdreq->time = jiffies;
176
177 INIT_HLIST_NODE(&sdreq->node);
178
179 return sdreq;
180}
181
182void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
183{
184 kfree(sdp->tlv);
185 kfree(sdp);
186}
187
188void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
189{
190 struct nfc_llcp_sdp_tlv *sdp;
191 struct hlist_node *n;
192
193 hlist_for_each_entry_safe(sdp, n, head, node) {
194 hlist_del(&sdp->node);
195
196 nfc_llcp_free_sdp_tlv(sdp);
197 }
198}
199
200int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
201 u8 *tlv_array, u16 tlv_array_len)
202{
203 u8 *tlv = tlv_array, type, length, offset = 0;
204
205 pr_debug("TLV array length %d\n", tlv_array_len);
206
207 if (local == NULL)
208 return -ENODEV;
209
210 while (offset < tlv_array_len) {
211 type = tlv[0];
212 length = tlv[1];
213
214 pr_debug("type 0x%x length %d\n", type, length);
215
216 switch (type) {
217 case LLCP_TLV_VERSION:
218 local->remote_version = llcp_tlv_version(tlv);
219 break;
220 case LLCP_TLV_MIUX:
221 local->remote_miu = llcp_tlv_miux(tlv) + 128;
222 break;
223 case LLCP_TLV_WKS:
224 local->remote_wks = llcp_tlv_wks(tlv);
225 break;
226 case LLCP_TLV_LTO:
227 local->remote_lto = llcp_tlv_lto(tlv) * 10;
228 break;
229 case LLCP_TLV_OPT:
230 local->remote_opt = llcp_tlv_opt(tlv);
231 break;
232 default:
233 pr_err("Invalid gt tlv value 0x%x\n", type);
234 break;
235 }
236
237 offset += length + 2;
238 tlv += length + 2;
239 }
240
241 pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
242 local->remote_version, local->remote_miu,
243 local->remote_lto, local->remote_opt,
244 local->remote_wks);
245
246 return 0;
247}
248
249int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
250 u8 *tlv_array, u16 tlv_array_len)
251{
252 u8 *tlv = tlv_array, type, length, offset = 0;
253
254 pr_debug("TLV array length %d\n", tlv_array_len);
255
256 if (sock == NULL)
257 return -ENOTCONN;
258
259 while (offset < tlv_array_len) {
260 type = tlv[0];
261 length = tlv[1];
262
263 pr_debug("type 0x%x length %d\n", type, length);
264
265 switch (type) {
266 case LLCP_TLV_MIUX:
267 sock->remote_miu = llcp_tlv_miux(tlv) + 128;
268 break;
269 case LLCP_TLV_RW:
270 sock->remote_rw = llcp_tlv_rw(tlv);
271 break;
272 case LLCP_TLV_SN:
273 break;
274 default:
275 pr_err("Invalid gt tlv value 0x%x\n", type);
276 break;
277 }
278
279 offset += length + 2;
280 tlv += length + 2;
281 }
282
283 pr_debug("sock %p rw %d miu %d\n", sock,
284 sock->remote_rw, sock->remote_miu);
285
286 return 0;
287}
288
289static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
290 u8 dsap, u8 ssap, u8 ptype)
291{
292 u8 header[2];
293
294 pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
295
296 header[0] = (u8)((dsap << 2) | (ptype >> 2));
297 header[1] = (u8)((ptype << 6) | ssap);
298
299 pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
300
301 memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
302
303 return pdu;
304}
305
306static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
307 u8 tlv_length)
308{
309 /* XXX Add an skb length check */
310
311 if (tlv == NULL)
312 return NULL;
313
314 memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
315
316 return pdu;
317}
318
319static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
320 u8 cmd, u16 size)
321{
322 struct sk_buff *skb;
323 int err;
324
325 if (sock->ssap == 0)
326 return NULL;
327
328 skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
329 size + LLCP_HEADER_SIZE, &err);
330 if (skb == NULL) {
331 pr_err("Could not allocate PDU\n");
332 return NULL;
333 }
334
335 skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
336
337 return skb;
338}
339
340int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
341{
342 struct sk_buff *skb;
343 struct nfc_dev *dev;
344 struct nfc_llcp_local *local;
345
346 pr_debug("Sending DISC\n");
347
348 local = sock->local;
349 if (local == NULL)
350 return -ENODEV;
351
352 dev = sock->dev;
353 if (dev == NULL)
354 return -ENODEV;
355
356 skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
357 if (skb == NULL)
358 return -ENOMEM;
359
360 skb_queue_tail(&local->tx_queue, skb);
361
362 return 0;
363}
364
365int nfc_llcp_send_symm(struct nfc_dev *dev)
366{
367 struct sk_buff *skb;
368 struct nfc_llcp_local *local;
369 u16 size = 0;
370
371 pr_debug("Sending SYMM\n");
372
373 local = nfc_llcp_find_local(dev);
374 if (local == NULL)
375 return -ENODEV;
376
377 size += LLCP_HEADER_SIZE;
378 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
379
380 skb = alloc_skb(size, GFP_KERNEL);
381 if (skb == NULL)
382 return -ENOMEM;
383
384 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
385
386 skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
387
388 __net_timestamp(skb);
389
390 nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX);
391
392 return nfc_data_exchange(dev, local->target_idx, skb,
393 nfc_llcp_recv, local);
394}
395
396int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
397{
398 struct nfc_llcp_local *local;
399 struct sk_buff *skb;
400 u8 *service_name_tlv = NULL, service_name_tlv_length;
401 u8 *miux_tlv = NULL, miux_tlv_length;
402 u8 *rw_tlv = NULL, rw_tlv_length, rw;
403 int err;
404 u16 size = 0;
405 __be16 miux;
406
407 pr_debug("Sending CONNECT\n");
408
409 local = sock->local;
410 if (local == NULL)
411 return -ENODEV;
412
413 if (sock->service_name != NULL) {
414 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
415 sock->service_name,
416 sock->service_name_len,
417 &service_name_tlv_length);
418 size += service_name_tlv_length;
419 }
420
421 /* If the socket parameters are not set, use the local ones */
422 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
423 local->miux : sock->miux;
424 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
425
426 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427 &miux_tlv_length);
428 size += miux_tlv_length;
429
430 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
431 size += rw_tlv_length;
432
433 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
434
435 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
436 if (skb == NULL) {
437 err = -ENOMEM;
438 goto error_tlv;
439 }
440
441 llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length);
442 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
443 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
444
445 skb_queue_tail(&local->tx_queue, skb);
446
447 err = 0;
448
449error_tlv:
450 if (err)
451 pr_err("error %d\n", err);
452
453 kfree(service_name_tlv);
454 kfree(miux_tlv);
455 kfree(rw_tlv);
456
457 return err;
458}
459
460int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
461{
462 struct nfc_llcp_local *local;
463 struct sk_buff *skb;
464 u8 *miux_tlv = NULL, miux_tlv_length;
465 u8 *rw_tlv = NULL, rw_tlv_length, rw;
466 int err;
467 u16 size = 0;
468 __be16 miux;
469
470 pr_debug("Sending CC\n");
471
472 local = sock->local;
473 if (local == NULL)
474 return -ENODEV;
475
476 /* If the socket parameters are not set, use the local ones */
477 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
478 local->miux : sock->miux;
479 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
480
481 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
482 &miux_tlv_length);
483 size += miux_tlv_length;
484
485 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
486 size += rw_tlv_length;
487
488 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
489 if (skb == NULL) {
490 err = -ENOMEM;
491 goto error_tlv;
492 }
493
494 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
495 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
496
497 skb_queue_tail(&local->tx_queue, skb);
498
499 err = 0;
500
501error_tlv:
502 if (err)
503 pr_err("error %d\n", err);
504
505 kfree(miux_tlv);
506 kfree(rw_tlv);
507
508 return err;
509}
510
511static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
512 size_t tlv_length)
513{
514 struct sk_buff *skb;
515 struct nfc_dev *dev;
516 u16 size = 0;
517
518 if (local == NULL)
519 return ERR_PTR(-ENODEV);
520
521 dev = local->dev;
522 if (dev == NULL)
523 return ERR_PTR(-ENODEV);
524
525 size += LLCP_HEADER_SIZE;
526 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
527 size += tlv_length;
528
529 skb = alloc_skb(size, GFP_KERNEL);
530 if (skb == NULL)
531 return ERR_PTR(-ENOMEM);
532
533 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
534
535 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
536
537 return skb;
538}
539
540int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
541 struct hlist_head *tlv_list, size_t tlvs_len)
542{
543 struct nfc_llcp_sdp_tlv *sdp;
544 struct hlist_node *n;
545 struct sk_buff *skb;
546
547 skb = nfc_llcp_allocate_snl(local, tlvs_len);
548 if (IS_ERR(skb))
549 return PTR_ERR(skb);
550
551 hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
552 memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len);
553
554 hlist_del(&sdp->node);
555
556 nfc_llcp_free_sdp_tlv(sdp);
557 }
558
559 skb_queue_tail(&local->tx_queue, skb);
560
561 return 0;
562}
563
564int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
565 struct hlist_head *tlv_list, size_t tlvs_len)
566{
567 struct nfc_llcp_sdp_tlv *sdreq;
568 struct hlist_node *n;
569 struct sk_buff *skb;
570
571 skb = nfc_llcp_allocate_snl(local, tlvs_len);
572 if (IS_ERR(skb))
573 return PTR_ERR(skb);
574
575 mutex_lock(&local->sdreq_lock);
576
577 if (hlist_empty(&local->pending_sdreqs))
578 mod_timer(&local->sdreq_timer,
579 jiffies + msecs_to_jiffies(3 * local->remote_lto));
580
581 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
582 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
583
584 memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv,
585 sdreq->tlv_len);
586
587 hlist_del(&sdreq->node);
588
589 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
590 }
591
592 mutex_unlock(&local->sdreq_lock);
593
594 skb_queue_tail(&local->tx_queue, skb);
595
596 return 0;
597}
598
599int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
600{
601 struct sk_buff *skb;
602 struct nfc_dev *dev;
603 u16 size = 1; /* Reason code */
604
605 pr_debug("Sending DM reason 0x%x\n", reason);
606
607 if (local == NULL)
608 return -ENODEV;
609
610 dev = local->dev;
611 if (dev == NULL)
612 return -ENODEV;
613
614 size += LLCP_HEADER_SIZE;
615 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
616
617 skb = alloc_skb(size, GFP_KERNEL);
618 if (skb == NULL)
619 return -ENOMEM;
620
621 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
622
623 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
624
625 memcpy(skb_put(skb, 1), &reason, 1);
626
627 skb_queue_head(&local->tx_queue, skb);
628
629 return 0;
630}
631
632int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
633 struct msghdr *msg, size_t len)
634{
635 struct sk_buff *pdu;
636 struct sock *sk = &sock->sk;
637 struct nfc_llcp_local *local;
638 size_t frag_len = 0, remaining_len;
639 u8 *msg_data, *msg_ptr;
640 u16 remote_miu;
641
642 pr_debug("Send I frame len %zd\n", len);
643
644 local = sock->local;
645 if (local == NULL)
646 return -ENODEV;
647
648 /* Remote is ready but has not acknowledged our frames */
649 if((sock->remote_ready &&
650 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
651 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
652 pr_err("Pending queue is full %d frames\n",
653 skb_queue_len(&sock->tx_pending_queue));
654 return -ENOBUFS;
655 }
656
657 /* Remote is not ready and we've been queueing enough frames */
658 if ((!sock->remote_ready &&
659 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
660 pr_err("Tx queue is full %d frames\n",
661 skb_queue_len(&sock->tx_queue));
662 return -ENOBUFS;
663 }
664
665 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
666 if (msg_data == NULL)
667 return -ENOMEM;
668
669 if (memcpy_from_msg(msg_data, msg, len)) {
670 kfree(msg_data);
671 return -EFAULT;
672 }
673
674 remaining_len = len;
675 msg_ptr = msg_data;
676
677 do {
678 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
679 LLCP_DEFAULT_MIU : sock->remote_miu;
680
681 frag_len = min_t(size_t, remote_miu, remaining_len);
682
683 pr_debug("Fragment %zd bytes remaining %zd",
684 frag_len, remaining_len);
685
686 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
687 frag_len + LLCP_SEQUENCE_SIZE);
688 if (pdu == NULL) {
689 kfree(msg_data);
690 return -ENOMEM;
691 }
692
693 skb_put(pdu, LLCP_SEQUENCE_SIZE);
694
695 if (likely(frag_len > 0))
696 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
697
698 skb_queue_tail(&sock->tx_queue, pdu);
699
700 lock_sock(sk);
701
702 nfc_llcp_queue_i_frames(sock);
703
704 release_sock(sk);
705
706 remaining_len -= frag_len;
707 msg_ptr += frag_len;
708 } while (remaining_len > 0);
709
710 kfree(msg_data);
711
712 return len;
713}
714
715int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
716 struct msghdr *msg, size_t len)
717{
718 struct sk_buff *pdu;
719 struct nfc_llcp_local *local;
720 size_t frag_len = 0, remaining_len;
721 u8 *msg_ptr, *msg_data;
722 u16 remote_miu;
723 int err;
724
725 pr_debug("Send UI frame len %zd\n", len);
726
727 local = sock->local;
728 if (local == NULL)
729 return -ENODEV;
730
731 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
732 if (msg_data == NULL)
733 return -ENOMEM;
734
735 if (memcpy_from_msg(msg_data, msg, len)) {
736 kfree(msg_data);
737 return -EFAULT;
738 }
739
740 remaining_len = len;
741 msg_ptr = msg_data;
742
743 do {
744 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
745 local->remote_miu : sock->remote_miu;
746
747 frag_len = min_t(size_t, remote_miu, remaining_len);
748
749 pr_debug("Fragment %zd bytes remaining %zd",
750 frag_len, remaining_len);
751
752 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
753 frag_len + LLCP_HEADER_SIZE, &err);
754 if (pdu == NULL) {
755 pr_err("Could not allocate PDU\n");
756 continue;
757 }
758
759 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
760
761 if (likely(frag_len > 0))
762 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
763
764 /* No need to check for the peer RW for UI frames */
765 skb_queue_tail(&local->tx_queue, pdu);
766
767 remaining_len -= frag_len;
768 msg_ptr += frag_len;
769 } while (remaining_len > 0);
770
771 kfree(msg_data);
772
773 return len;
774}
775
776int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
777{
778 struct sk_buff *skb;
779 struct nfc_llcp_local *local;
780
781 pr_debug("Send rr nr %d\n", sock->recv_n);
782
783 local = sock->local;
784 if (local == NULL)
785 return -ENODEV;
786
787 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
788 if (skb == NULL)
789 return -ENOMEM;
790
791 skb_put(skb, LLCP_SEQUENCE_SIZE);
792
793 skb->data[2] = sock->recv_n;
794
795 skb_queue_head(&local->tx_queue, skb);
796
797 return 0;
798}
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 const 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(const 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(const 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(const u8 *tlv)
50{
51 return llcp_tlv8(tlv, LLCP_TLV_VERSION);
52}
53
54static u16 llcp_tlv_miux(const u8 *tlv)
55{
56 return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
57}
58
59static u16 llcp_tlv_wks(const u8 *tlv)
60{
61 return llcp_tlv16(tlv, LLCP_TLV_WKS);
62}
63
64static u16 llcp_tlv_lto(const u8 *tlv)
65{
66 return llcp_tlv8(tlv, LLCP_TLV_LTO);
67}
68
69static u8 llcp_tlv_opt(const u8 *tlv)
70{
71 return llcp_tlv8(tlv, LLCP_TLV_OPT);
72}
73
74static u8 llcp_tlv_rw(const u8 *tlv)
75{
76 return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
77}
78
79u8 *nfc_llcp_build_tlv(u8 type, const 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, const 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 const u8 *tlv_array, u16 tlv_array_len)
194{
195 const u8 *tlv = tlv_array;
196 u8 type, length, offset = 0;
197
198 pr_debug("TLV array length %d\n", tlv_array_len);
199
200 if (local == NULL)
201 return -ENODEV;
202
203 while (offset < tlv_array_len) {
204 type = tlv[0];
205 length = tlv[1];
206
207 pr_debug("type 0x%x length %d\n", type, length);
208
209 switch (type) {
210 case LLCP_TLV_VERSION:
211 local->remote_version = llcp_tlv_version(tlv);
212 break;
213 case LLCP_TLV_MIUX:
214 local->remote_miu = llcp_tlv_miux(tlv) + 128;
215 break;
216 case LLCP_TLV_WKS:
217 local->remote_wks = llcp_tlv_wks(tlv);
218 break;
219 case LLCP_TLV_LTO:
220 local->remote_lto = llcp_tlv_lto(tlv) * 10;
221 break;
222 case LLCP_TLV_OPT:
223 local->remote_opt = llcp_tlv_opt(tlv);
224 break;
225 default:
226 pr_err("Invalid gt tlv value 0x%x\n", type);
227 break;
228 }
229
230 offset += length + 2;
231 tlv += length + 2;
232 }
233
234 pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
235 local->remote_version, local->remote_miu,
236 local->remote_lto, local->remote_opt,
237 local->remote_wks);
238
239 return 0;
240}
241
242int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
243 const u8 *tlv_array, u16 tlv_array_len)
244{
245 const u8 *tlv = tlv_array;
246 u8 type, length, offset = 0;
247
248 pr_debug("TLV array length %d\n", tlv_array_len);
249
250 if (sock == NULL)
251 return -ENOTCONN;
252
253 while (offset < tlv_array_len) {
254 type = tlv[0];
255 length = tlv[1];
256
257 pr_debug("type 0x%x length %d\n", type, length);
258
259 switch (type) {
260 case LLCP_TLV_MIUX:
261 sock->remote_miu = llcp_tlv_miux(tlv) + 128;
262 break;
263 case LLCP_TLV_RW:
264 sock->remote_rw = llcp_tlv_rw(tlv);
265 break;
266 case LLCP_TLV_SN:
267 break;
268 default:
269 pr_err("Invalid gt tlv value 0x%x\n", type);
270 break;
271 }
272
273 offset += length + 2;
274 tlv += length + 2;
275 }
276
277 pr_debug("sock %p rw %d miu %d\n", sock,
278 sock->remote_rw, sock->remote_miu);
279
280 return 0;
281}
282
283static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
284 u8 dsap, u8 ssap, u8 ptype)
285{
286 u8 header[2];
287
288 pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
289
290 header[0] = (u8)((dsap << 2) | (ptype >> 2));
291 header[1] = (u8)((ptype << 6) | ssap);
292
293 pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
294
295 skb_put_data(pdu, header, LLCP_HEADER_SIZE);
296
297 return pdu;
298}
299
300static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, const u8 *tlv,
301 u8 tlv_length)
302{
303 /* XXX Add an skb length check */
304
305 if (tlv == NULL)
306 return NULL;
307
308 skb_put_data(pdu, tlv, tlv_length);
309
310 return pdu;
311}
312
313static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
314 u8 cmd, u16 size)
315{
316 struct sk_buff *skb;
317 int err;
318
319 if (sock->ssap == 0)
320 return NULL;
321
322 skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
323 size + LLCP_HEADER_SIZE, &err);
324 if (skb == NULL) {
325 pr_err("Could not allocate PDU\n");
326 return NULL;
327 }
328
329 skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
330
331 return skb;
332}
333
334int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
335{
336 struct sk_buff *skb;
337 struct nfc_dev *dev;
338 struct nfc_llcp_local *local;
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 int err;
363
364 local = nfc_llcp_find_local(dev);
365 if (local == NULL)
366 return -ENODEV;
367
368 size += LLCP_HEADER_SIZE;
369 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
370
371 skb = alloc_skb(size, GFP_KERNEL);
372 if (skb == NULL) {
373 err = -ENOMEM;
374 goto out;
375 }
376
377 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
378
379 skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
380
381 __net_timestamp(skb);
382
383 nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX);
384
385 err = nfc_data_exchange(dev, local->target_idx, skb,
386 nfc_llcp_recv, local);
387out:
388 nfc_llcp_local_put(local);
389 return err;
390}
391
392int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
393{
394 struct nfc_llcp_local *local;
395 struct sk_buff *skb;
396 const u8 *service_name_tlv = NULL;
397 const u8 *miux_tlv = NULL;
398 const u8 *rw_tlv = NULL;
399 u8 service_name_tlv_length = 0;
400 u8 miux_tlv_length, rw_tlv_length, rw;
401 int err;
402 u16 size = 0;
403 __be16 miux;
404
405 local = sock->local;
406 if (local == NULL)
407 return -ENODEV;
408
409 if (sock->service_name != NULL) {
410 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
411 sock->service_name,
412 sock->service_name_len,
413 &service_name_tlv_length);
414 if (!service_name_tlv) {
415 err = -ENOMEM;
416 goto error_tlv;
417 }
418 size += service_name_tlv_length;
419 }
420
421 /* If the socket parameters are not set, use the local ones */
422 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
423 local->miux : sock->miux;
424 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
425
426 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427 &miux_tlv_length);
428 if (!miux_tlv) {
429 err = -ENOMEM;
430 goto error_tlv;
431 }
432 size += miux_tlv_length;
433
434 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
435 if (!rw_tlv) {
436 err = -ENOMEM;
437 goto error_tlv;
438 }
439 size += rw_tlv_length;
440
441 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
442
443 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
444 if (skb == NULL) {
445 err = -ENOMEM;
446 goto error_tlv;
447 }
448
449 llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length);
450 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
451 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
452
453 skb_queue_tail(&local->tx_queue, skb);
454
455 err = 0;
456
457error_tlv:
458 if (err)
459 pr_err("error %d\n", err);
460
461 kfree(service_name_tlv);
462 kfree(miux_tlv);
463 kfree(rw_tlv);
464
465 return err;
466}
467
468int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
469{
470 struct nfc_llcp_local *local;
471 struct sk_buff *skb;
472 const u8 *miux_tlv = NULL;
473 const u8 *rw_tlv = NULL;
474 u8 miux_tlv_length, rw_tlv_length, rw;
475 int err;
476 u16 size = 0;
477 __be16 miux;
478
479 local = sock->local;
480 if (local == NULL)
481 return -ENODEV;
482
483 /* If the socket parameters are not set, use the local ones */
484 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
485 local->miux : sock->miux;
486 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
487
488 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
489 &miux_tlv_length);
490 if (!miux_tlv) {
491 err = -ENOMEM;
492 goto error_tlv;
493 }
494 size += miux_tlv_length;
495
496 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
497 if (!rw_tlv) {
498 err = -ENOMEM;
499 goto error_tlv;
500 }
501 size += rw_tlv_length;
502
503 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
504 if (skb == NULL) {
505 err = -ENOMEM;
506 goto error_tlv;
507 }
508
509 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
510 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
511
512 skb_queue_tail(&local->tx_queue, skb);
513
514 err = 0;
515
516error_tlv:
517 if (err)
518 pr_err("error %d\n", err);
519
520 kfree(miux_tlv);
521 kfree(rw_tlv);
522
523 return err;
524}
525
526static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
527 size_t tlv_length)
528{
529 struct sk_buff *skb;
530 struct nfc_dev *dev;
531 u16 size = 0;
532
533 if (local == NULL)
534 return ERR_PTR(-ENODEV);
535
536 dev = local->dev;
537 if (dev == NULL)
538 return ERR_PTR(-ENODEV);
539
540 size += LLCP_HEADER_SIZE;
541 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
542 size += tlv_length;
543
544 skb = alloc_skb(size, GFP_KERNEL);
545 if (skb == NULL)
546 return ERR_PTR(-ENOMEM);
547
548 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
549
550 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
551
552 return skb;
553}
554
555int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
556 struct hlist_head *tlv_list, size_t tlvs_len)
557{
558 struct nfc_llcp_sdp_tlv *sdp;
559 struct hlist_node *n;
560 struct sk_buff *skb;
561
562 skb = nfc_llcp_allocate_snl(local, tlvs_len);
563 if (IS_ERR(skb))
564 return PTR_ERR(skb);
565
566 hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
567 skb_put_data(skb, sdp->tlv, sdp->tlv_len);
568
569 hlist_del(&sdp->node);
570
571 nfc_llcp_free_sdp_tlv(sdp);
572 }
573
574 skb_queue_tail(&local->tx_queue, skb);
575
576 return 0;
577}
578
579int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
580 struct hlist_head *tlv_list, size_t tlvs_len)
581{
582 struct nfc_llcp_sdp_tlv *sdreq;
583 struct hlist_node *n;
584 struct sk_buff *skb;
585
586 skb = nfc_llcp_allocate_snl(local, tlvs_len);
587 if (IS_ERR(skb))
588 return PTR_ERR(skb);
589
590 mutex_lock(&local->sdreq_lock);
591
592 if (hlist_empty(&local->pending_sdreqs))
593 mod_timer(&local->sdreq_timer,
594 jiffies + msecs_to_jiffies(3 * local->remote_lto));
595
596 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
597 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
598
599 skb_put_data(skb, sdreq->tlv, sdreq->tlv_len);
600
601 hlist_del(&sdreq->node);
602
603 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
604 }
605
606 mutex_unlock(&local->sdreq_lock);
607
608 skb_queue_tail(&local->tx_queue, skb);
609
610 return 0;
611}
612
613int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
614{
615 struct sk_buff *skb;
616 struct nfc_dev *dev;
617 u16 size = 1; /* Reason code */
618
619 pr_debug("Sending DM reason 0x%x\n", reason);
620
621 if (local == NULL)
622 return -ENODEV;
623
624 dev = local->dev;
625 if (dev == NULL)
626 return -ENODEV;
627
628 size += LLCP_HEADER_SIZE;
629 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
630
631 skb = alloc_skb(size, GFP_KERNEL);
632 if (skb == NULL)
633 return -ENOMEM;
634
635 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
636
637 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
638
639 skb_put_data(skb, &reason, 1);
640
641 skb_queue_head(&local->tx_queue, skb);
642
643 return 0;
644}
645
646int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
647 struct msghdr *msg, size_t len)
648{
649 struct sk_buff *pdu;
650 struct sock *sk = &sock->sk;
651 struct nfc_llcp_local *local;
652 size_t frag_len = 0, remaining_len;
653 u8 *msg_data, *msg_ptr;
654 u16 remote_miu;
655
656 pr_debug("Send I frame len %zd\n", len);
657
658 local = sock->local;
659 if (local == NULL)
660 return -ENODEV;
661
662 /* Remote is ready but has not acknowledged our frames */
663 if((sock->remote_ready &&
664 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
665 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
666 pr_err("Pending queue is full %d frames\n",
667 skb_queue_len(&sock->tx_pending_queue));
668 return -ENOBUFS;
669 }
670
671 /* Remote is not ready and we've been queueing enough frames */
672 if ((!sock->remote_ready &&
673 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
674 pr_err("Tx queue is full %d frames\n",
675 skb_queue_len(&sock->tx_queue));
676 return -ENOBUFS;
677 }
678
679 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
680 if (msg_data == NULL)
681 return -ENOMEM;
682
683 if (memcpy_from_msg(msg_data, msg, len)) {
684 kfree(msg_data);
685 return -EFAULT;
686 }
687
688 remaining_len = len;
689 msg_ptr = msg_data;
690
691 do {
692 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
693 LLCP_DEFAULT_MIU : sock->remote_miu;
694
695 frag_len = min_t(size_t, remote_miu, remaining_len);
696
697 pr_debug("Fragment %zd bytes remaining %zd",
698 frag_len, remaining_len);
699
700 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
701 frag_len + LLCP_SEQUENCE_SIZE);
702 if (pdu == NULL) {
703 kfree(msg_data);
704 return -ENOMEM;
705 }
706
707 skb_put(pdu, LLCP_SEQUENCE_SIZE);
708
709 if (likely(frag_len > 0))
710 skb_put_data(pdu, msg_ptr, frag_len);
711
712 skb_queue_tail(&sock->tx_queue, pdu);
713
714 lock_sock(sk);
715
716 nfc_llcp_queue_i_frames(sock);
717
718 release_sock(sk);
719
720 remaining_len -= frag_len;
721 msg_ptr += frag_len;
722 } while (remaining_len > 0);
723
724 kfree(msg_data);
725
726 return len;
727}
728
729int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
730 struct msghdr *msg, size_t len)
731{
732 struct sk_buff *pdu;
733 struct nfc_llcp_local *local;
734 size_t frag_len = 0, remaining_len;
735 u8 *msg_ptr, *msg_data;
736 u16 remote_miu;
737 int err;
738
739 pr_debug("Send UI frame len %zd\n", len);
740
741 local = sock->local;
742 if (local == NULL)
743 return -ENODEV;
744
745 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
746 if (msg_data == NULL)
747 return -ENOMEM;
748
749 if (memcpy_from_msg(msg_data, msg, len)) {
750 kfree(msg_data);
751 return -EFAULT;
752 }
753
754 remaining_len = len;
755 msg_ptr = msg_data;
756
757 do {
758 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
759 local->remote_miu : sock->remote_miu;
760
761 frag_len = min_t(size_t, remote_miu, remaining_len);
762
763 pr_debug("Fragment %zd bytes remaining %zd",
764 frag_len, remaining_len);
765
766 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, 0,
767 frag_len + LLCP_HEADER_SIZE, &err);
768 if (pdu == NULL) {
769 pr_err("Could not allocate PDU (error=%d)\n", err);
770 len -= remaining_len;
771 if (len == 0)
772 len = err;
773 break;
774 }
775
776 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
777
778 if (likely(frag_len > 0))
779 skb_put_data(pdu, msg_ptr, frag_len);
780
781 /* No need to check for the peer RW for UI frames */
782 skb_queue_tail(&local->tx_queue, pdu);
783
784 remaining_len -= frag_len;
785 msg_ptr += frag_len;
786 } while (remaining_len > 0);
787
788 kfree(msg_data);
789
790 return len;
791}
792
793int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
794{
795 struct sk_buff *skb;
796 struct nfc_llcp_local *local;
797
798 pr_debug("Send rr nr %d\n", sock->recv_n);
799
800 local = sock->local;
801 if (local == NULL)
802 return -ENODEV;
803
804 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
805 if (skb == NULL)
806 return -ENOMEM;
807
808 skb_put(skb, LLCP_SEQUENCE_SIZE);
809
810 skb->data[2] = sock->recv_n;
811
812 skb_queue_head(&local->tx_queue, skb);
813
814 return 0;
815}