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
18 static 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
llcp_tlv8(const u8 * tlv,u8 type)32 static 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
llcp_tlv16(const u8 * tlv,u8 type)40 static 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
llcp_tlv_version(const u8 * tlv)49 static u8 llcp_tlv_version(const u8 *tlv)
50 {
51 return llcp_tlv8(tlv, LLCP_TLV_VERSION);
52 }
53
llcp_tlv_miux(const u8 * tlv)54 static u16 llcp_tlv_miux(const u8 *tlv)
55 {
56 return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
57 }
58
llcp_tlv_wks(const u8 * tlv)59 static u16 llcp_tlv_wks(const u8 *tlv)
60 {
61 return llcp_tlv16(tlv, LLCP_TLV_WKS);
62 }
63
llcp_tlv_lto(const u8 * tlv)64 static u16 llcp_tlv_lto(const u8 *tlv)
65 {
66 return llcp_tlv8(tlv, LLCP_TLV_LTO);
67 }
68
llcp_tlv_opt(const u8 * tlv)69 static u8 llcp_tlv_opt(const u8 *tlv)
70 {
71 return llcp_tlv8(tlv, LLCP_TLV_OPT);
72 }
73
llcp_tlv_rw(const u8 * tlv)74 static u8 llcp_tlv_rw(const u8 *tlv)
75 {
76 return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
77 }
78
nfc_llcp_build_tlv(u8 type,const u8 * value,u8 value_length,u8 * tlv_length)79 u8 *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
nfc_llcp_build_sdres_tlv(u8 tid,u8 sap)106 struct 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_obj(struct nfc_llcp_sdp_tlv);
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
nfc_llcp_build_sdreq_tlv(u8 tid,const char * uri,size_t uri_len)133 struct 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_obj(struct nfc_llcp_sdp_tlv);
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
nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv * sdp)174 void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
175 {
176 kfree(sdp->tlv);
177 kfree(sdp);
178 }
179
nfc_llcp_free_sdp_tlv_list(struct hlist_head * head)180 void 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
nfc_llcp_parse_gb_tlv(struct nfc_llcp_local * local,const u8 * tlv_array,u16 tlv_array_len)192 int 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;
197 u16 offset = 0;
198
199 pr_debug("TLV array length %d\n", tlv_array_len);
200
201 if (local == NULL)
202 return -ENODEV;
203
204 while (offset < tlv_array_len) {
205 if (offset + 2 > tlv_array_len)
206 return -EINVAL;
207
208 type = tlv[0];
209 length = tlv[1];
210
211 if (offset + 2 + length > tlv_array_len)
212 return -EINVAL;
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
nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock * sock,const u8 * tlv_array,u16 tlv_array_len)249 int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
250 const u8 *tlv_array, u16 tlv_array_len)
251 {
252 const u8 *tlv = tlv_array;
253 u8 type, length;
254 u16 offset = 0;
255
256 pr_debug("TLV array length %d\n", tlv_array_len);
257
258 if (sock == NULL)
259 return -ENOTCONN;
260
261 while (offset < tlv_array_len) {
262 if (offset + 2 > tlv_array_len)
263 return -EINVAL;
264
265 type = tlv[0];
266 length = tlv[1];
267
268 if (offset + 2 + length > tlv_array_len)
269 return -EINVAL;
270
271 pr_debug("type 0x%x length %d\n", type, length);
272
273 switch (type) {
274 case LLCP_TLV_MIUX:
275 sock->remote_miu = llcp_tlv_miux(tlv) + 128;
276 break;
277 case LLCP_TLV_RW:
278 sock->remote_rw = llcp_tlv_rw(tlv);
279 break;
280 case LLCP_TLV_SN:
281 break;
282 default:
283 pr_err("Invalid gt tlv value 0x%x\n", type);
284 break;
285 }
286
287 offset += length + 2;
288 tlv += length + 2;
289 }
290
291 pr_debug("sock %p rw %d miu %d\n", sock,
292 sock->remote_rw, sock->remote_miu);
293
294 return 0;
295 }
296
llcp_add_header(struct sk_buff * pdu,u8 dsap,u8 ssap,u8 ptype)297 static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
298 u8 dsap, u8 ssap, u8 ptype)
299 {
300 u8 header[2];
301
302 pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
303
304 header[0] = (u8)((dsap << 2) | (ptype >> 2));
305 header[1] = (u8)((ptype << 6) | ssap);
306
307 pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
308
309 skb_put_data(pdu, header, LLCP_HEADER_SIZE);
310
311 return pdu;
312 }
313
llcp_add_tlv(struct sk_buff * pdu,const u8 * tlv,u8 tlv_length)314 static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, const u8 *tlv,
315 u8 tlv_length)
316 {
317 /* XXX Add an skb length check */
318
319 if (tlv == NULL)
320 return NULL;
321
322 skb_put_data(pdu, tlv, tlv_length);
323
324 return pdu;
325 }
326
llcp_allocate_pdu(struct nfc_llcp_sock * sock,u8 cmd,u16 size)327 static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
328 u8 cmd, u16 size)
329 {
330 struct sk_buff *skb;
331 int err;
332
333 if (sock->ssap == 0)
334 return NULL;
335
336 skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
337 size + LLCP_HEADER_SIZE, &err);
338 if (skb == NULL) {
339 pr_err("Could not allocate PDU\n");
340 return NULL;
341 }
342
343 skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
344
345 return skb;
346 }
347
nfc_llcp_send_disconnect(struct nfc_llcp_sock * sock)348 int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
349 {
350 struct sk_buff *skb;
351 struct nfc_dev *dev;
352 struct nfc_llcp_local *local;
353
354 local = sock->local;
355 if (local == NULL)
356 return -ENODEV;
357
358 dev = sock->dev;
359 if (dev == NULL)
360 return -ENODEV;
361
362 skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
363 if (skb == NULL)
364 return -ENOMEM;
365
366 skb_queue_tail(&local->tx_queue, skb);
367
368 return 0;
369 }
370
nfc_llcp_send_symm(struct nfc_dev * dev)371 int nfc_llcp_send_symm(struct nfc_dev *dev)
372 {
373 struct sk_buff *skb;
374 struct nfc_llcp_local *local;
375 u16 size = 0;
376 int err;
377
378 local = nfc_llcp_find_local(dev);
379 if (local == NULL)
380 return -ENODEV;
381
382 size += LLCP_HEADER_SIZE;
383 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
384
385 skb = alloc_skb(size, GFP_KERNEL);
386 if (skb == NULL) {
387 err = -ENOMEM;
388 goto out;
389 }
390
391 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
392
393 skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
394
395 __net_timestamp(skb);
396
397 nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX);
398
399 err = nfc_data_exchange(dev, local->target_idx, skb,
400 nfc_llcp_recv, local);
401 out:
402 nfc_llcp_local_put(local);
403 return err;
404 }
405
nfc_llcp_send_connect(struct nfc_llcp_sock * sock)406 int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
407 {
408 struct nfc_llcp_local *local;
409 struct sk_buff *skb;
410 const u8 *service_name_tlv = NULL;
411 const u8 *miux_tlv = NULL;
412 const u8 *rw_tlv = NULL;
413 u8 service_name_tlv_length = 0;
414 u8 miux_tlv_length, rw_tlv_length, rw;
415 int err;
416 u16 size = 0;
417 __be16 miux;
418
419 local = sock->local;
420 if (local == NULL)
421 return -ENODEV;
422
423 if (sock->service_name != NULL) {
424 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
425 sock->service_name,
426 sock->service_name_len,
427 &service_name_tlv_length);
428 if (!service_name_tlv) {
429 err = -ENOMEM;
430 goto error_tlv;
431 }
432 size += service_name_tlv_length;
433 }
434
435 /* If the socket parameters are not set, use the local ones */
436 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
437 local->miux : sock->miux;
438 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
439
440 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
441 &miux_tlv_length);
442 if (!miux_tlv) {
443 err = -ENOMEM;
444 goto error_tlv;
445 }
446 size += miux_tlv_length;
447
448 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
449 if (!rw_tlv) {
450 err = -ENOMEM;
451 goto error_tlv;
452 }
453 size += rw_tlv_length;
454
455 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
456
457 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
458 if (skb == NULL) {
459 err = -ENOMEM;
460 goto error_tlv;
461 }
462
463 llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length);
464 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
465 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
466
467 skb_queue_tail(&local->tx_queue, skb);
468
469 err = 0;
470
471 error_tlv:
472 if (err)
473 pr_err("error %d\n", err);
474
475 kfree(service_name_tlv);
476 kfree(miux_tlv);
477 kfree(rw_tlv);
478
479 return err;
480 }
481
nfc_llcp_send_cc(struct nfc_llcp_sock * sock)482 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
483 {
484 struct nfc_llcp_local *local;
485 struct sk_buff *skb;
486 const u8 *miux_tlv = NULL;
487 const u8 *rw_tlv = NULL;
488 u8 miux_tlv_length, rw_tlv_length, rw;
489 int err;
490 u16 size = 0;
491 __be16 miux;
492
493 local = sock->local;
494 if (local == NULL)
495 return -ENODEV;
496
497 /* If the socket parameters are not set, use the local ones */
498 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
499 local->miux : sock->miux;
500 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
501
502 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
503 &miux_tlv_length);
504 if (!miux_tlv) {
505 err = -ENOMEM;
506 goto error_tlv;
507 }
508 size += miux_tlv_length;
509
510 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
511 if (!rw_tlv) {
512 err = -ENOMEM;
513 goto error_tlv;
514 }
515 size += rw_tlv_length;
516
517 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
518 if (skb == NULL) {
519 err = -ENOMEM;
520 goto error_tlv;
521 }
522
523 llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
524 llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
525
526 skb_queue_tail(&local->tx_queue, skb);
527
528 err = 0;
529
530 error_tlv:
531 if (err)
532 pr_err("error %d\n", err);
533
534 kfree(miux_tlv);
535 kfree(rw_tlv);
536
537 return err;
538 }
539
nfc_llcp_allocate_snl(struct nfc_llcp_local * local,size_t tlv_length)540 static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
541 size_t tlv_length)
542 {
543 struct sk_buff *skb;
544 struct nfc_dev *dev;
545 u16 size = 0;
546
547 if (local == NULL)
548 return ERR_PTR(-ENODEV);
549
550 dev = local->dev;
551 if (dev == NULL)
552 return ERR_PTR(-ENODEV);
553
554 size += LLCP_HEADER_SIZE;
555 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
556 size += tlv_length;
557
558 skb = alloc_skb(size, GFP_KERNEL);
559 if (skb == NULL)
560 return ERR_PTR(-ENOMEM);
561
562 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
563
564 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
565
566 return skb;
567 }
568
nfc_llcp_send_snl_sdres(struct nfc_llcp_local * local,struct hlist_head * tlv_list,size_t tlvs_len)569 int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
570 struct hlist_head *tlv_list, size_t tlvs_len)
571 {
572 struct nfc_llcp_sdp_tlv *sdp;
573 struct hlist_node *n;
574 struct sk_buff *skb;
575
576 skb = nfc_llcp_allocate_snl(local, tlvs_len);
577 if (IS_ERR(skb))
578 return PTR_ERR(skb);
579
580 hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
581 skb_put_data(skb, sdp->tlv, sdp->tlv_len);
582
583 hlist_del(&sdp->node);
584
585 nfc_llcp_free_sdp_tlv(sdp);
586 }
587
588 skb_queue_tail(&local->tx_queue, skb);
589
590 return 0;
591 }
592
nfc_llcp_send_snl_sdreq(struct nfc_llcp_local * local,struct hlist_head * tlv_list,size_t tlvs_len)593 int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
594 struct hlist_head *tlv_list, size_t tlvs_len)
595 {
596 struct nfc_llcp_sdp_tlv *sdreq;
597 struct hlist_node *n;
598 struct sk_buff *skb;
599
600 skb = nfc_llcp_allocate_snl(local, tlvs_len);
601 if (IS_ERR(skb))
602 return PTR_ERR(skb);
603
604 mutex_lock(&local->sdreq_lock);
605
606 if (hlist_empty(&local->pending_sdreqs))
607 mod_timer(&local->sdreq_timer,
608 jiffies + msecs_to_jiffies(3 * local->remote_lto));
609
610 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
611 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
612
613 skb_put_data(skb, sdreq->tlv, sdreq->tlv_len);
614
615 hlist_del(&sdreq->node);
616
617 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
618 }
619
620 mutex_unlock(&local->sdreq_lock);
621
622 skb_queue_tail(&local->tx_queue, skb);
623
624 return 0;
625 }
626
nfc_llcp_send_dm(struct nfc_llcp_local * local,u8 ssap,u8 dsap,u8 reason)627 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
628 {
629 struct sk_buff *skb;
630 struct nfc_dev *dev;
631 u16 size = 1; /* Reason code */
632
633 pr_debug("Sending DM reason 0x%x\n", reason);
634
635 if (local == NULL)
636 return -ENODEV;
637
638 dev = local->dev;
639 if (dev == NULL)
640 return -ENODEV;
641
642 size += LLCP_HEADER_SIZE;
643 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
644
645 skb = alloc_skb(size, GFP_KERNEL);
646 if (skb == NULL)
647 return -ENOMEM;
648
649 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
650
651 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
652
653 skb_put_data(skb, &reason, 1);
654
655 skb_queue_head(&local->tx_queue, skb);
656
657 return 0;
658 }
659
nfc_llcp_send_i_frame(struct nfc_llcp_sock * sock,struct msghdr * msg,size_t len)660 int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
661 struct msghdr *msg, size_t len)
662 {
663 struct sk_buff *pdu;
664 struct sock *sk = &sock->sk;
665 struct nfc_llcp_local *local;
666 size_t frag_len = 0, remaining_len;
667 u8 *msg_data, *msg_ptr;
668 u16 remote_miu;
669
670 pr_debug("Send I frame len %zd\n", len);
671
672 local = sock->local;
673 if (local == NULL)
674 return -ENODEV;
675
676 /* Remote is ready but has not acknowledged our frames */
677 if((sock->remote_ready &&
678 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
679 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
680 pr_err("Pending queue is full %d frames\n",
681 skb_queue_len(&sock->tx_pending_queue));
682 return -ENOBUFS;
683 }
684
685 /* Remote is not ready and we've been queueing enough frames */
686 if ((!sock->remote_ready &&
687 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
688 pr_err("Tx queue is full %d frames\n",
689 skb_queue_len(&sock->tx_queue));
690 return -ENOBUFS;
691 }
692
693 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
694 if (msg_data == NULL)
695 return -ENOMEM;
696
697 if (memcpy_from_msg(msg_data, msg, len)) {
698 kfree(msg_data);
699 return -EFAULT;
700 }
701
702 remaining_len = len;
703 msg_ptr = msg_data;
704
705 do {
706 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
707 LLCP_DEFAULT_MIU : sock->remote_miu;
708
709 frag_len = min_t(size_t, remote_miu, remaining_len);
710
711 pr_debug("Fragment %zd bytes remaining %zd",
712 frag_len, remaining_len);
713
714 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
715 frag_len + LLCP_SEQUENCE_SIZE);
716 if (pdu == NULL) {
717 kfree(msg_data);
718 return -ENOMEM;
719 }
720
721 skb_put(pdu, LLCP_SEQUENCE_SIZE);
722
723 if (likely(frag_len > 0))
724 skb_put_data(pdu, msg_ptr, frag_len);
725
726 skb_queue_tail(&sock->tx_queue, pdu);
727
728 lock_sock(sk);
729
730 nfc_llcp_queue_i_frames(sock);
731
732 release_sock(sk);
733
734 remaining_len -= frag_len;
735 msg_ptr += frag_len;
736 } while (remaining_len > 0);
737
738 kfree(msg_data);
739
740 return len;
741 }
742
nfc_llcp_send_ui_frame(struct nfc_llcp_sock * sock,u8 ssap,u8 dsap,struct msghdr * msg,size_t len)743 int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
744 struct msghdr *msg, size_t len)
745 {
746 struct sk_buff *pdu;
747 struct nfc_llcp_local *local;
748 size_t frag_len = 0, remaining_len;
749 u8 *msg_ptr, *msg_data;
750 u16 remote_miu;
751 int err;
752
753 pr_debug("Send UI frame len %zd\n", len);
754
755 local = sock->local;
756 if (local == NULL)
757 return -ENODEV;
758
759 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
760 if (msg_data == NULL)
761 return -ENOMEM;
762
763 if (memcpy_from_msg(msg_data, msg, len)) {
764 kfree(msg_data);
765 return -EFAULT;
766 }
767
768 remaining_len = len;
769 msg_ptr = msg_data;
770
771 do {
772 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
773 local->remote_miu : sock->remote_miu;
774
775 frag_len = min_t(size_t, remote_miu, remaining_len);
776
777 pr_debug("Fragment %zd bytes remaining %zd",
778 frag_len, remaining_len);
779
780 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, 0,
781 frag_len + LLCP_HEADER_SIZE, &err);
782 if (pdu == NULL) {
783 pr_err("Could not allocate PDU (error=%d)\n", err);
784 len -= remaining_len;
785 if (len == 0)
786 len = err;
787 break;
788 }
789
790 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
791
792 if (likely(frag_len > 0))
793 skb_put_data(pdu, msg_ptr, frag_len);
794
795 spin_lock(&local->tx_queue.lock);
796
797 if (list_empty(&local->list)) {
798 spin_unlock(&local->tx_queue.lock);
799
800 kfree_skb(pdu);
801
802 len -= remaining_len;
803 if (len == 0)
804 len = -ENXIO;
805 break;
806 }
807
808 /* No need to check for the peer RW for UI frames */
809 __skb_queue_tail(&local->tx_queue, pdu);
810
811 spin_unlock(&local->tx_queue.lock);
812
813 remaining_len -= frag_len;
814 msg_ptr += frag_len;
815 } while (remaining_len > 0);
816
817 kfree(msg_data);
818
819 return len;
820 }
821
nfc_llcp_send_rr(struct nfc_llcp_sock * sock)822 int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
823 {
824 struct sk_buff *skb;
825 struct nfc_llcp_local *local;
826
827 pr_debug("Send rr nr %d\n", sock->recv_n);
828
829 local = sock->local;
830 if (local == NULL)
831 return -ENODEV;
832
833 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
834 if (skb == NULL)
835 return -ENOMEM;
836
837 skb_put(skb, LLCP_SEQUENCE_SIZE);
838
839 skb->data[2] = sock->recv_n;
840
841 skb_queue_head(&local->tx_queue, skb);
842
843 return 0;
844 }
845