NFC: Forward LLCP datagrams to userspace
[deliverable/linux.git] / net / nfc / llcp / commands.c
CommitLineData
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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, write to the
16 * Free Software Foundation, Inc.,
17 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 */
19
20#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
21
22#include <linux/init.h>
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/nfc.h>
26
27#include <net/nfc/nfc.h>
28
29#include "../nfc.h"
30#include "llcp.h"
31
32static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
33 0,
34 1, /* VERSION */
35 2, /* MIUX */
36 2, /* WKS */
37 1, /* LTO */
38 1, /* RW */
39 0, /* SN */
40 1, /* OPT */
41 0, /* SDREQ */
42 2, /* SDRES */
43
44};
45
46static u8 llcp_tlv8(u8 *tlv, u8 type)
47{
48 if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
49 return 0;
50
51 return tlv[2];
52}
53
76762b73 54static u16 llcp_tlv16(u8 *tlv, u8 type)
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SO
55{
56 if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
57 return 0;
58
59 return be16_to_cpu(*((__be16 *)(tlv + 2)));
60}
61
62
63static u8 llcp_tlv_version(u8 *tlv)
64{
65 return llcp_tlv8(tlv, LLCP_TLV_VERSION);
66}
67
68static u16 llcp_tlv_miux(u8 *tlv)
69{
76762b73 70 return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
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71}
72
73static u16 llcp_tlv_wks(u8 *tlv)
74{
75 return llcp_tlv16(tlv, LLCP_TLV_WKS);
76}
77
78static u16 llcp_tlv_lto(u8 *tlv)
79{
80 return llcp_tlv8(tlv, LLCP_TLV_LTO);
81}
82
83static u8 llcp_tlv_opt(u8 *tlv)
84{
85 return llcp_tlv8(tlv, LLCP_TLV_OPT);
86}
87
88static u8 llcp_tlv_rw(u8 *tlv)
89{
90 return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
91}
92
93u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
94{
95 u8 *tlv, length;
96
97 pr_debug("type %d\n", type);
98
99 if (type >= LLCP_TLV_MAX)
100 return NULL;
101
102 length = llcp_tlv_length[type];
103 if (length == 0 && value_length == 0)
104 return NULL;
324b0af6 105 else if (length == 0)
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106 length = value_length;
107
108 *tlv_length = 2 + length;
109 tlv = kzalloc(2 + length, GFP_KERNEL);
110 if (tlv == NULL)
111 return tlv;
112
113 tlv[0] = type;
114 tlv[1] = length;
115 memcpy(tlv + 2, value, length);
116
117 return tlv;
118}
119
7a06e586
SO
120int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
121 u8 *tlv_array, u16 tlv_array_len)
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122{
123 u8 *tlv = tlv_array, type, length, offset = 0;
124
125 pr_debug("TLV array length %d\n", tlv_array_len);
126
127 if (local == NULL)
128 return -ENODEV;
129
130 while (offset < tlv_array_len) {
131 type = tlv[0];
132 length = tlv[1];
133
134 pr_debug("type 0x%x length %d\n", type, length);
135
136 switch (type) {
137 case LLCP_TLV_VERSION:
138 local->remote_version = llcp_tlv_version(tlv);
139 break;
140 case LLCP_TLV_MIUX:
141 local->remote_miu = llcp_tlv_miux(tlv) + 128;
142 break;
143 case LLCP_TLV_WKS:
144 local->remote_wks = llcp_tlv_wks(tlv);
145 break;
146 case LLCP_TLV_LTO:
147 local->remote_lto = llcp_tlv_lto(tlv) * 10;
148 break;
149 case LLCP_TLV_OPT:
150 local->remote_opt = llcp_tlv_opt(tlv);
151 break;
7a06e586
SO
152 default:
153 pr_err("Invalid gt tlv value 0x%x\n", type);
154 break;
155 }
156
157 offset += length + 2;
158 tlv += length + 2;
159 }
160
161 pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
162 local->remote_version, local->remote_miu,
163 local->remote_lto, local->remote_opt,
164 local->remote_wks);
165
166 return 0;
167}
168
169int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
170 u8 *tlv_array, u16 tlv_array_len)
171{
172 u8 *tlv = tlv_array, type, length, offset = 0;
173
174 pr_debug("TLV array length %d\n", tlv_array_len);
175
176 if (sock == NULL)
177 return -ENOTCONN;
178
179 while (offset < tlv_array_len) {
180 type = tlv[0];
181 length = tlv[1];
182
183 pr_debug("type 0x%x length %d\n", type, length);
184
185 switch (type) {
93d7e490
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186 case LLCP_TLV_MIUX:
187 sock->miu = llcp_tlv_miux(tlv) + 128;
188 break;
d646960f 189 case LLCP_TLV_RW:
7a06e586 190 sock->rw = llcp_tlv_rw(tlv);
d646960f 191 break;
9dda50f4
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192 case LLCP_TLV_SN:
193 break;
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194 default:
195 pr_err("Invalid gt tlv value 0x%x\n", type);
196 break;
197 }
198
199 offset += length + 2;
200 tlv += length + 2;
201 }
202
93d7e490 203 pr_debug("sock %p rw %d miu %d\n", sock, sock->rw, sock->miu);
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204
205 return 0;
206}
207
208static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
427a2eb1 209 u8 dsap, u8 ssap, u8 ptype)
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210{
211 u8 header[2];
212
213 pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
214
215 header[0] = (u8)((dsap << 2) | (ptype >> 2));
216 header[1] = (u8)((ptype << 6) | ssap);
217
218 pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
219
220 memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
221
222 return pdu;
223}
224
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225static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
226 u8 tlv_length)
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227{
228 /* XXX Add an skb length check */
229
230 if (tlv == NULL)
231 return NULL;
232
233 memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
234
235 return pdu;
236}
237
238static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
427a2eb1 239 u8 cmd, u16 size)
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240{
241 struct sk_buff *skb;
242 int err;
243
244 if (sock->ssap == 0)
245 return NULL;
246
247 skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
427a2eb1 248 size + LLCP_HEADER_SIZE, &err);
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249 if (skb == NULL) {
250 pr_err("Could not allocate PDU\n");
251 return NULL;
252 }
253
254 skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
255
256 return skb;
257}
258
259int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
260{
261 struct sk_buff *skb;
262 struct nfc_dev *dev;
263 struct nfc_llcp_local *local;
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264
265 pr_debug("Sending DISC\n");
266
267 local = sock->local;
268 if (local == NULL)
269 return -ENODEV;
270
271 dev = sock->dev;
272 if (dev == NULL)
273 return -ENODEV;
274
92223906 275 skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
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276 if (skb == NULL)
277 return -ENOMEM;
278
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279 skb_queue_tail(&local->tx_queue, skb);
280
281 return 0;
282}
283
284int nfc_llcp_send_symm(struct nfc_dev *dev)
285{
286 struct sk_buff *skb;
287 struct nfc_llcp_local *local;
288 u16 size = 0;
289
290 pr_debug("Sending SYMM\n");
291
292 local = nfc_llcp_find_local(dev);
293 if (local == NULL)
294 return -ENODEV;
295
296 size += LLCP_HEADER_SIZE;
297 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
298
299 skb = alloc_skb(size, GFP_KERNEL);
300 if (skb == NULL)
301 return -ENOMEM;
302
303 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
304
305 skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
306
4463523b
TE
307 nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_TX);
308
d646960f 309 return nfc_data_exchange(dev, local->target_idx, skb,
427a2eb1 310 nfc_llcp_recv, local);
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311}
312
313int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
314{
315 struct nfc_llcp_local *local;
316 struct sk_buff *skb;
317 u8 *service_name_tlv = NULL, service_name_tlv_length;
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318 u8 *miux_tlv = NULL, miux_tlv_length;
319 u8 *rw_tlv = NULL, rw_tlv_length, rw;
320 __be16 miux;
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321 int err;
322 u16 size = 0;
323
324 pr_debug("Sending CONNECT\n");
325
326 local = sock->local;
327 if (local == NULL)
328 return -ENODEV;
329
330 if (sock->service_name != NULL) {
331 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
427a2eb1
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332 sock->service_name,
333 sock->service_name_len,
334 &service_name_tlv_length);
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335 size += service_name_tlv_length;
336 }
337
eda21f16 338 miux = cpu_to_be16(LLCP_MAX_MIUX);
427a2eb1
SO
339 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
340 &miux_tlv_length);
eda21f16
SO
341 size += miux_tlv_length;
342
343 rw = LLCP_MAX_RW;
344 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
345 size += rw_tlv_length;
346
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347 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
348
349 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
350 if (skb == NULL) {
351 err = -ENOMEM;
352 goto error_tlv;
353 }
354
355 if (service_name_tlv != NULL)
356 skb = llcp_add_tlv(skb, service_name_tlv,
427a2eb1 357 service_name_tlv_length);
d646960f 358
eda21f16
SO
359 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
360 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
361
d646960f
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362 skb_queue_tail(&local->tx_queue, skb);
363
364 return 0;
365
366error_tlv:
367 pr_err("error %d\n", err);
368
369 kfree(service_name_tlv);
eda21f16
SO
370 kfree(miux_tlv);
371 kfree(rw_tlv);
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372
373 return err;
374}
375
376int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
377{
378 struct nfc_llcp_local *local;
379 struct sk_buff *skb;
eda21f16
SO
380 u8 *miux_tlv = NULL, miux_tlv_length;
381 u8 *rw_tlv = NULL, rw_tlv_length, rw;
382 __be16 miux;
383 int err;
384 u16 size = 0;
d646960f
SO
385
386 pr_debug("Sending CC\n");
387
388 local = sock->local;
389 if (local == NULL)
390 return -ENODEV;
391
eda21f16 392 miux = cpu_to_be16(LLCP_MAX_MIUX);
427a2eb1
SO
393 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
394 &miux_tlv_length);
eda21f16
SO
395 size += miux_tlv_length;
396
397 rw = LLCP_MAX_RW;
398 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
399 size += rw_tlv_length;
400
401 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
402 if (skb == NULL) {
403 err = -ENOMEM;
404 goto error_tlv;
405 }
406
407 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
408 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
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409
410 skb_queue_tail(&local->tx_queue, skb);
411
412 return 0;
eda21f16
SO
413
414error_tlv:
415 pr_err("error %d\n", err);
416
417 kfree(miux_tlv);
418 kfree(rw_tlv);
419
420 return err;
d646960f
SO
421}
422
c43bb03d
SO
423int nfc_llcp_send_snl(struct nfc_llcp_local *local, u8 tid, u8 sap)
424{
425 struct sk_buff *skb;
426 struct nfc_dev *dev;
427 u8 *sdres_tlv = NULL, sdres_tlv_length, sdres[2];
428 u16 size = 0;
429
430 pr_debug("Sending SNL tid 0x%x sap 0x%x\n", tid, sap);
431
432 if (local == NULL)
433 return -ENODEV;
434
435 dev = local->dev;
436 if (dev == NULL)
437 return -ENODEV;
438
439 sdres[0] = tid;
440 sdres[1] = sap;
441 sdres_tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, sdres, 0,
442 &sdres_tlv_length);
443 if (sdres_tlv == NULL)
444 return -ENOMEM;
445
446 size += LLCP_HEADER_SIZE;
447 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
448 size += sdres_tlv_length;
449
450 skb = alloc_skb(size, GFP_KERNEL);
451 if (skb == NULL) {
452 kfree(sdres_tlv);
453 return -ENOMEM;
454 }
455
456 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
457
458 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
459
460 memcpy(skb_put(skb, sdres_tlv_length), sdres_tlv, sdres_tlv_length);
461
462 skb_queue_tail(&local->tx_queue, skb);
463
464 kfree(sdres_tlv);
465
466 return 0;
467}
468
d646960f
SO
469int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
470{
471 struct sk_buff *skb;
472 struct nfc_dev *dev;
473 u16 size = 1; /* Reason code */
474
475 pr_debug("Sending DM reason 0x%x\n", reason);
476
477 if (local == NULL)
478 return -ENODEV;
479
480 dev = local->dev;
481 if (dev == NULL)
482 return -ENODEV;
483
484 size += LLCP_HEADER_SIZE;
485 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
486
487 skb = alloc_skb(size, GFP_KERNEL);
488 if (skb == NULL)
489 return -ENOMEM;
490
491 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
492
ffc29315 493 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
d646960f
SO
494
495 memcpy(skb_put(skb, 1), &reason, 1);
496
497 skb_queue_head(&local->tx_queue, skb);
498
499 return 0;
500}
501
502int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
503{
504 struct sk_buff *skb;
505 struct nfc_llcp_local *local;
506
507 pr_debug("Send DISC\n");
508
509 local = sock->local;
510 if (local == NULL)
511 return -ENODEV;
512
513 skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
514 if (skb == NULL)
515 return -ENOMEM;
516
517 skb_queue_head(&local->tx_queue, skb);
518
519 return 0;
520}
53a0ac2e
SO
521
522int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
427a2eb1 523 struct msghdr *msg, size_t len)
53a0ac2e
SO
524{
525 struct sk_buff *pdu;
e65b0f46
SO
526 struct sock *sk = &sock->sk;
527 struct nfc_llcp_local *local;
528 size_t frag_len = 0, remaining_len;
529 u8 *msg_data, *msg_ptr;
53a0ac2e 530
e65b0f46 531 pr_debug("Send I frame len %zd\n", len);
53a0ac2e 532
e65b0f46
SO
533 local = sock->local;
534 if (local == NULL)
535 return -ENODEV;
53a0ac2e 536
e65b0f46
SO
537 msg_data = kzalloc(len, GFP_KERNEL);
538 if (msg_data == NULL)
539 return -ENOMEM;
53a0ac2e 540
e65b0f46 541 if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
427a2eb1
SO
542 kfree(msg_data);
543 return -EFAULT;
53a0ac2e
SO
544 }
545
e65b0f46
SO
546 remaining_len = len;
547 msg_ptr = msg_data;
548
549 while (remaining_len > 0) {
550
93d7e490 551 frag_len = min_t(size_t, sock->miu, remaining_len);
53a0ac2e 552
e65b0f46
SO
553 pr_debug("Fragment %zd bytes remaining %zd",
554 frag_len, remaining_len);
53a0ac2e 555
e65b0f46
SO
556 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
557 frag_len + LLCP_SEQUENCE_SIZE);
558 if (pdu == NULL)
559 return -ENOMEM;
560
561 skb_put(pdu, LLCP_SEQUENCE_SIZE);
562
563 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
564
bdbc59b3 565 skb_queue_tail(&sock->tx_queue, pdu);
e65b0f46
SO
566
567 lock_sock(sk);
568
569 nfc_llcp_queue_i_frames(sock);
570
571 release_sock(sk);
572
573 remaining_len -= frag_len;
b4838d12 574 msg_ptr += frag_len;
e65b0f46 575 }
53a0ac2e 576
e65b0f46 577 kfree(msg_data);
53a0ac2e 578
43472fff 579 return len;
53a0ac2e 580}
d094afa1
SO
581
582int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
583{
584 struct sk_buff *skb;
585 struct nfc_llcp_local *local;
586
587 pr_debug("Send rr nr %d\n", sock->recv_n);
588
589 local = sock->local;
590 if (local == NULL)
591 return -ENODEV;
592
593 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
594 if (skb == NULL)
595 return -ENOMEM;
596
597 skb_put(skb, LLCP_SEQUENCE_SIZE);
598
279cf174 599 skb->data[2] = sock->recv_n;
d094afa1
SO
600
601 skb_queue_head(&local->tx_queue, skb);
602
603 return 0;
604}
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