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
30 static 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
llcp_tlv8(u8 * tlv,u8 type)44 static 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
llcp_tlv16(u8 * tlv,u8 type)52 static 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
llcp_tlv_version(u8 * tlv)61 static u8 llcp_tlv_version(u8 *tlv)
62 {
63 return llcp_tlv8(tlv, LLCP_TLV_VERSION);
64 }
65
llcp_tlv_miux(u8 * tlv)66 static u16 llcp_tlv_miux(u8 *tlv)
67 {
68 return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
69 }
70
llcp_tlv_wks(u8 * tlv)71 static u16 llcp_tlv_wks(u8 *tlv)
72 {
73 return llcp_tlv16(tlv, LLCP_TLV_WKS);
74 }
75
llcp_tlv_lto(u8 * tlv)76 static u16 llcp_tlv_lto(u8 *tlv)
77 {
78 return llcp_tlv8(tlv, LLCP_TLV_LTO);
79 }
80
llcp_tlv_opt(u8 * tlv)81 static u8 llcp_tlv_opt(u8 *tlv)
82 {
83 return llcp_tlv8(tlv, LLCP_TLV_OPT);
84 }
85
llcp_tlv_rw(u8 * tlv)86 static u8 llcp_tlv_rw(u8 *tlv)
87 {
88 return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
89 }
90
nfc_llcp_build_tlv(u8 type,u8 * value,u8 value_length,u8 * tlv_length)91 u8 *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
nfc_llcp_build_sdres_tlv(u8 tid,u8 sap)118 struct 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
nfc_llcp_build_sdreq_tlv(u8 tid,char * uri,size_t uri_len)145 struct 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
nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv * sdp)186 void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
187 {
188 kfree(sdp->tlv);
189 kfree(sdp);
190 }
191
nfc_llcp_free_sdp_tlv_list(struct hlist_head * head)192 void 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
nfc_llcp_parse_gb_tlv(struct nfc_llcp_local * local,u8 * tlv_array,u16 tlv_array_len)204 int 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
nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock * sock,u8 * tlv_array,u16 tlv_array_len)253 int 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
llcp_add_header(struct sk_buff * pdu,u8 dsap,u8 ssap,u8 ptype)293 static 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 memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
306
307 return pdu;
308 }
309
llcp_add_tlv(struct sk_buff * pdu,u8 * tlv,u8 tlv_length)310 static 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 memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
319
320 return pdu;
321 }
322
llcp_allocate_pdu(struct nfc_llcp_sock * sock,u8 cmd,u16 size)323 static 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
nfc_llcp_send_disconnect(struct nfc_llcp_sock * sock)344 int 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
nfc_llcp_send_symm(struct nfc_dev * dev)369 int 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
nfc_llcp_send_connect(struct nfc_llcp_sock * sock)400 int 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 if (!service_name_tlv) {
423 err = -ENOMEM;
424 goto error_tlv;
425 }
426 size += service_name_tlv_length;
427 }
428
429 /* If the socket parameters are not set, use the local ones */
430 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
431 local->miux : sock->miux;
432 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
433
434 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
435 &miux_tlv_length);
436 if (!miux_tlv) {
437 err = -ENOMEM;
438 goto error_tlv;
439 }
440 size += miux_tlv_length;
441
442 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
443 if (!rw_tlv) {
444 err = -ENOMEM;
445 goto error_tlv;
446 }
447 size += rw_tlv_length;
448
449 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
450
451 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
452 if (skb == NULL) {
453 err = -ENOMEM;
454 goto error_tlv;
455 }
456
457 if (service_name_tlv != NULL)
458 skb = llcp_add_tlv(skb, service_name_tlv,
459 service_name_tlv_length);
460
461 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
462 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
463
464 skb_queue_tail(&local->tx_queue, skb);
465
466 return 0;
467
468 error_tlv:
469 pr_err("error %d\n", err);
470
471 kfree(service_name_tlv);
472 kfree(miux_tlv);
473 kfree(rw_tlv);
474
475 return err;
476 }
477
nfc_llcp_send_cc(struct nfc_llcp_sock * sock)478 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
479 {
480 struct nfc_llcp_local *local;
481 struct sk_buff *skb;
482 u8 *miux_tlv = NULL, miux_tlv_length;
483 u8 *rw_tlv = NULL, rw_tlv_length, rw;
484 int err;
485 u16 size = 0;
486 __be16 miux;
487
488 pr_debug("Sending CC\n");
489
490 local = sock->local;
491 if (local == NULL)
492 return -ENODEV;
493
494 /* If the socket parameters are not set, use the local ones */
495 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
496 local->miux : sock->miux;
497 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
498
499 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
500 &miux_tlv_length);
501 if (!miux_tlv) {
502 err = -ENOMEM;
503 goto error_tlv;
504 }
505 size += miux_tlv_length;
506
507 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
508 if (!rw_tlv) {
509 err = -ENOMEM;
510 goto error_tlv;
511 }
512 size += rw_tlv_length;
513
514 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
515 if (skb == NULL) {
516 err = -ENOMEM;
517 goto error_tlv;
518 }
519
520 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
521 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
522
523 skb_queue_tail(&local->tx_queue, skb);
524
525 return 0;
526
527 error_tlv:
528 pr_err("error %d\n", err);
529
530 kfree(miux_tlv);
531 kfree(rw_tlv);
532
533 return err;
534 }
535
nfc_llcp_allocate_snl(struct nfc_llcp_local * local,size_t tlv_length)536 static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
537 size_t tlv_length)
538 {
539 struct sk_buff *skb;
540 struct nfc_dev *dev;
541 u16 size = 0;
542
543 if (local == NULL)
544 return ERR_PTR(-ENODEV);
545
546 dev = local->dev;
547 if (dev == NULL)
548 return ERR_PTR(-ENODEV);
549
550 size += LLCP_HEADER_SIZE;
551 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
552 size += tlv_length;
553
554 skb = alloc_skb(size, GFP_KERNEL);
555 if (skb == NULL)
556 return ERR_PTR(-ENOMEM);
557
558 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
559
560 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
561
562 return skb;
563 }
564
nfc_llcp_send_snl_sdres(struct nfc_llcp_local * local,struct hlist_head * tlv_list,size_t tlvs_len)565 int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
566 struct hlist_head *tlv_list, size_t tlvs_len)
567 {
568 struct nfc_llcp_sdp_tlv *sdp;
569 struct hlist_node *n;
570 struct sk_buff *skb;
571
572 skb = nfc_llcp_allocate_snl(local, tlvs_len);
573 if (IS_ERR(skb))
574 return PTR_ERR(skb);
575
576 hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
577 memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len);
578
579 hlist_del(&sdp->node);
580
581 nfc_llcp_free_sdp_tlv(sdp);
582 }
583
584 skb_queue_tail(&local->tx_queue, skb);
585
586 return 0;
587 }
588
nfc_llcp_send_snl_sdreq(struct nfc_llcp_local * local,struct hlist_head * tlv_list,size_t tlvs_len)589 int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
590 struct hlist_head *tlv_list, size_t tlvs_len)
591 {
592 struct nfc_llcp_sdp_tlv *sdreq;
593 struct hlist_node *n;
594 struct sk_buff *skb;
595
596 skb = nfc_llcp_allocate_snl(local, tlvs_len);
597 if (IS_ERR(skb))
598 return PTR_ERR(skb);
599
600 mutex_lock(&local->sdreq_lock);
601
602 if (hlist_empty(&local->pending_sdreqs))
603 mod_timer(&local->sdreq_timer,
604 jiffies + msecs_to_jiffies(3 * local->remote_lto));
605
606 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
607 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
608
609 memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv,
610 sdreq->tlv_len);
611
612 hlist_del(&sdreq->node);
613
614 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
615 }
616
617 mutex_unlock(&local->sdreq_lock);
618
619 skb_queue_tail(&local->tx_queue, skb);
620
621 return 0;
622 }
623
nfc_llcp_send_dm(struct nfc_llcp_local * local,u8 ssap,u8 dsap,u8 reason)624 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
625 {
626 struct sk_buff *skb;
627 struct nfc_dev *dev;
628 u16 size = 1; /* Reason code */
629
630 pr_debug("Sending DM reason 0x%x\n", reason);
631
632 if (local == NULL)
633 return -ENODEV;
634
635 dev = local->dev;
636 if (dev == NULL)
637 return -ENODEV;
638
639 size += LLCP_HEADER_SIZE;
640 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
641
642 skb = alloc_skb(size, GFP_KERNEL);
643 if (skb == NULL)
644 return -ENOMEM;
645
646 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
647
648 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
649
650 memcpy(skb_put(skb, 1), &reason, 1);
651
652 skb_queue_head(&local->tx_queue, skb);
653
654 return 0;
655 }
656
nfc_llcp_send_i_frame(struct nfc_llcp_sock * sock,struct msghdr * msg,size_t len)657 int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
658 struct msghdr *msg, size_t len)
659 {
660 struct sk_buff *pdu;
661 struct sock *sk = &sock->sk;
662 struct nfc_llcp_local *local;
663 size_t frag_len = 0, remaining_len;
664 u8 *msg_data, *msg_ptr;
665 u16 remote_miu;
666
667 pr_debug("Send I frame len %zd\n", len);
668
669 local = sock->local;
670 if (local == NULL)
671 return -ENODEV;
672
673 /* Remote is ready but has not acknowledged our frames */
674 if((sock->remote_ready &&
675 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
676 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
677 pr_err("Pending queue is full %d frames\n",
678 skb_queue_len(&sock->tx_pending_queue));
679 return -ENOBUFS;
680 }
681
682 /* Remote is not ready and we've been queueing enough frames */
683 if ((!sock->remote_ready &&
684 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
685 pr_err("Tx queue is full %d frames\n",
686 skb_queue_len(&sock->tx_queue));
687 return -ENOBUFS;
688 }
689
690 msg_data = kzalloc(len, GFP_KERNEL);
691 if (msg_data == NULL)
692 return -ENOMEM;
693
694 if (memcpy_from_msg(msg_data, msg, len)) {
695 kfree(msg_data);
696 return -EFAULT;
697 }
698
699 remaining_len = len;
700 msg_ptr = msg_data;
701
702 do {
703 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
704 LLCP_DEFAULT_MIU : sock->remote_miu;
705
706 frag_len = min_t(size_t, remote_miu, remaining_len);
707
708 pr_debug("Fragment %zd bytes remaining %zd",
709 frag_len, remaining_len);
710
711 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
712 frag_len + LLCP_SEQUENCE_SIZE);
713 if (pdu == NULL) {
714 kfree(msg_data);
715 return -ENOMEM;
716 }
717
718 skb_put(pdu, LLCP_SEQUENCE_SIZE);
719
720 if (likely(frag_len > 0))
721 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
722
723 skb_queue_tail(&sock->tx_queue, pdu);
724
725 lock_sock(sk);
726
727 nfc_llcp_queue_i_frames(sock);
728
729 release_sock(sk);
730
731 remaining_len -= frag_len;
732 msg_ptr += frag_len;
733 } while (remaining_len > 0);
734
735 kfree(msg_data);
736
737 return len;
738 }
739
nfc_llcp_send_ui_frame(struct nfc_llcp_sock * sock,u8 ssap,u8 dsap,struct msghdr * msg,size_t len)740 int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
741 struct msghdr *msg, size_t len)
742 {
743 struct sk_buff *pdu;
744 struct nfc_llcp_local *local;
745 size_t frag_len = 0, remaining_len;
746 u8 *msg_ptr, *msg_data;
747 u16 remote_miu;
748 int err;
749
750 pr_debug("Send UI frame len %zd\n", len);
751
752 local = sock->local;
753 if (local == NULL)
754 return -ENODEV;
755
756 msg_data = kzalloc(len, GFP_KERNEL);
757 if (msg_data == NULL)
758 return -ENOMEM;
759
760 if (memcpy_from_msg(msg_data, msg, len)) {
761 kfree(msg_data);
762 return -EFAULT;
763 }
764
765 remaining_len = len;
766 msg_ptr = msg_data;
767
768 do {
769 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
770 local->remote_miu : sock->remote_miu;
771
772 frag_len = min_t(size_t, remote_miu, remaining_len);
773
774 pr_debug("Fragment %zd bytes remaining %zd",
775 frag_len, remaining_len);
776
777 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, 0,
778 frag_len + LLCP_HEADER_SIZE, &err);
779 if (pdu == NULL) {
780 pr_err("Could not allocate PDU (error=%d)\n", err);
781 len -= remaining_len;
782 if (len == 0)
783 len = err;
784 break;
785 }
786
787 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
788
789 if (likely(frag_len > 0))
790 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
791
792 /* No need to check for the peer RW for UI frames */
793 skb_queue_tail(&local->tx_queue, pdu);
794
795 remaining_len -= frag_len;
796 msg_ptr += frag_len;
797 } while (remaining_len > 0);
798
799 kfree(msg_data);
800
801 return len;
802 }
803
nfc_llcp_send_rr(struct nfc_llcp_sock * sock)804 int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
805 {
806 struct sk_buff *skb;
807 struct nfc_llcp_local *local;
808
809 pr_debug("Send rr nr %d\n", sock->recv_n);
810
811 local = sock->local;
812 if (local == NULL)
813 return -ENODEV;
814
815 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
816 if (skb == NULL)
817 return -ENOMEM;
818
819 skb_put(skb, LLCP_SEQUENCE_SIZE);
820
821 skb->data[2] = sock->recv_n;
822
823 skb_queue_head(&local->tx_queue, skb);
824
825 return 0;
826 }
827