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, miux; 405 406 pr_debug("Sending CONNECT\n"); 407 408 local = sock->local; 409 if (local == NULL) 410 return -ENODEV; 411 412 if (sock->service_name != NULL) { 413 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN, 414 sock->service_name, 415 sock->service_name_len, 416 &service_name_tlv_length); 417 size += service_name_tlv_length; 418 } 419 420 /* If the socket parameters are not set, use the local ones */ 421 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ? 422 local->miux : sock->miux; 423 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw; 424 425 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0, 426 &miux_tlv_length); 427 size += miux_tlv_length; 428 429 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length); 430 size += rw_tlv_length; 431 432 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len); 433 434 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size); 435 if (skb == NULL) { 436 err = -ENOMEM; 437 goto error_tlv; 438 } 439 440 if (service_name_tlv != NULL) 441 skb = llcp_add_tlv(skb, service_name_tlv, 442 service_name_tlv_length); 443 444 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 445 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 446 447 skb_queue_tail(&local->tx_queue, skb); 448 449 return 0; 450 451error_tlv: 452 pr_err("error %d\n", err); 453 454 kfree(service_name_tlv); 455 kfree(miux_tlv); 456 kfree(rw_tlv); 457 458 return err; 459} 460 461int nfc_llcp_send_cc(struct nfc_llcp_sock *sock) 462{ 463 struct nfc_llcp_local *local; 464 struct sk_buff *skb; 465 u8 *miux_tlv = NULL, miux_tlv_length; 466 u8 *rw_tlv = NULL, rw_tlv_length, rw; 467 int err; 468 u16 size = 0, 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 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 495 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 496 497 skb_queue_tail(&local->tx_queue, skb); 498 499 return 0; 500 501error_tlv: 502 pr_err("error %d\n", err); 503 504 kfree(miux_tlv); 505 kfree(rw_tlv); 506 507 return err; 508} 509 510static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local, 511 size_t tlv_length) 512{ 513 struct sk_buff *skb; 514 struct nfc_dev *dev; 515 u16 size = 0; 516 517 if (local == NULL) 518 return ERR_PTR(-ENODEV); 519 520 dev = local->dev; 521 if (dev == NULL) 522 return ERR_PTR(-ENODEV); 523 524 size += LLCP_HEADER_SIZE; 525 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 526 size += tlv_length; 527 528 skb = alloc_skb(size, GFP_KERNEL); 529 if (skb == NULL) 530 return ERR_PTR(-ENOMEM); 531 532 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 533 534 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL); 535 536 return skb; 537} 538 539int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local, 540 struct hlist_head *tlv_list, size_t tlvs_len) 541{ 542 struct nfc_llcp_sdp_tlv *sdp; 543 struct hlist_node *n; 544 struct sk_buff *skb; 545 546 skb = nfc_llcp_allocate_snl(local, tlvs_len); 547 if (IS_ERR(skb)) 548 return PTR_ERR(skb); 549 550 hlist_for_each_entry_safe(sdp, n, tlv_list, node) { 551 memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len); 552 553 hlist_del(&sdp->node); 554 555 nfc_llcp_free_sdp_tlv(sdp); 556 } 557 558 skb_queue_tail(&local->tx_queue, skb); 559 560 return 0; 561} 562 563int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local, 564 struct hlist_head *tlv_list, size_t tlvs_len) 565{ 566 struct nfc_llcp_sdp_tlv *sdreq; 567 struct hlist_node *n; 568 struct sk_buff *skb; 569 570 skb = nfc_llcp_allocate_snl(local, tlvs_len); 571 if (IS_ERR(skb)) 572 return PTR_ERR(skb); 573 574 mutex_lock(&local->sdreq_lock); 575 576 if (hlist_empty(&local->pending_sdreqs)) 577 mod_timer(&local->sdreq_timer, 578 jiffies + msecs_to_jiffies(3 * local->remote_lto)); 579 580 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) { 581 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri); 582 583 memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv, 584 sdreq->tlv_len); 585 586 hlist_del(&sdreq->node); 587 588 hlist_add_head(&sdreq->node, &local->pending_sdreqs); 589 } 590 591 mutex_unlock(&local->sdreq_lock); 592 593 skb_queue_tail(&local->tx_queue, skb); 594 595 return 0; 596} 597 598int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason) 599{ 600 struct sk_buff *skb; 601 struct nfc_dev *dev; 602 u16 size = 1; /* Reason code */ 603 604 pr_debug("Sending DM reason 0x%x\n", reason); 605 606 if (local == NULL) 607 return -ENODEV; 608 609 dev = local->dev; 610 if (dev == NULL) 611 return -ENODEV; 612 613 size += LLCP_HEADER_SIZE; 614 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 615 616 skb = alloc_skb(size, GFP_KERNEL); 617 if (skb == NULL) 618 return -ENOMEM; 619 620 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 621 622 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM); 623 624 memcpy(skb_put(skb, 1), &reason, 1); 625 626 skb_queue_head(&local->tx_queue, skb); 627 628 return 0; 629} 630 631int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock, 632 struct msghdr *msg, size_t len) 633{ 634 struct sk_buff *pdu; 635 struct sock *sk = &sock->sk; 636 struct nfc_llcp_local *local; 637 size_t frag_len = 0, remaining_len; 638 u8 *msg_data, *msg_ptr; 639 u16 remote_miu; 640 641 pr_debug("Send I frame len %zd\n", len); 642 643 local = sock->local; 644 if (local == NULL) 645 return -ENODEV; 646 647 /* Remote is ready but has not acknowledged our frames */ 648 if((sock->remote_ready && 649 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw && 650 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 651 pr_err("Pending queue is full %d frames\n", 652 skb_queue_len(&sock->tx_pending_queue)); 653 return -ENOBUFS; 654 } 655 656 /* Remote is not ready and we've been queueing enough frames */ 657 if ((!sock->remote_ready && 658 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 659 pr_err("Tx queue is full %d frames\n", 660 skb_queue_len(&sock->tx_queue)); 661 return -ENOBUFS; 662 } 663 664 msg_data = kzalloc(len, GFP_KERNEL); 665 if (msg_data == NULL) 666 return -ENOMEM; 667 668 if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) { 669 kfree(msg_data); 670 return -EFAULT; 671 } 672 673 remaining_len = len; 674 msg_ptr = msg_data; 675 676 do { 677 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 678 LLCP_DEFAULT_MIU : sock->remote_miu; 679 680 frag_len = min_t(size_t, remote_miu, remaining_len); 681 682 pr_debug("Fragment %zd bytes remaining %zd", 683 frag_len, remaining_len); 684 685 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I, 686 frag_len + LLCP_SEQUENCE_SIZE); 687 if (pdu == NULL) { 688 kfree(msg_data); 689 return -ENOMEM; 690 } 691 692 skb_put(pdu, LLCP_SEQUENCE_SIZE); 693 694 if (likely(frag_len > 0)) 695 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len); 696 697 skb_queue_tail(&sock->tx_queue, pdu); 698 699 lock_sock(sk); 700 701 nfc_llcp_queue_i_frames(sock); 702 703 release_sock(sk); 704 705 remaining_len -= frag_len; 706 msg_ptr += frag_len; 707 } while (remaining_len > 0); 708 709 kfree(msg_data); 710 711 return len; 712} 713 714int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap, 715 struct msghdr *msg, size_t len) 716{ 717 struct sk_buff *pdu; 718 struct nfc_llcp_local *local; 719 size_t frag_len = 0, remaining_len; 720 u8 *msg_ptr, *msg_data; 721 u16 remote_miu; 722 int err; 723 724 pr_debug("Send UI frame len %zd\n", len); 725 726 local = sock->local; 727 if (local == NULL) 728 return -ENODEV; 729 730 msg_data = kzalloc(len, GFP_KERNEL); 731 if (msg_data == NULL) 732 return -ENOMEM; 733 734 if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) { 735 kfree(msg_data); 736 return -EFAULT; 737 } 738 739 remaining_len = len; 740 msg_ptr = msg_data; 741 742 do { 743 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 744 local->remote_miu : sock->remote_miu; 745 746 frag_len = min_t(size_t, remote_miu, remaining_len); 747 748 pr_debug("Fragment %zd bytes remaining %zd", 749 frag_len, remaining_len); 750 751 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT, 752 frag_len + LLCP_HEADER_SIZE, &err); 753 if (pdu == NULL) { 754 pr_err("Could not allocate PDU\n"); 755 continue; 756 } 757 758 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI); 759 760 if (likely(frag_len > 0)) 761 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len); 762 763 /* No need to check for the peer RW for UI frames */ 764 skb_queue_tail(&local->tx_queue, pdu); 765 766 remaining_len -= frag_len; 767 msg_ptr += frag_len; 768 } while (remaining_len > 0); 769 770 kfree(msg_data); 771 772 return len; 773} 774 775int nfc_llcp_send_rr(struct nfc_llcp_sock *sock) 776{ 777 struct sk_buff *skb; 778 struct nfc_llcp_local *local; 779 780 pr_debug("Send rr nr %d\n", sock->recv_n); 781 782 local = sock->local; 783 if (local == NULL) 784 return -ENODEV; 785 786 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE); 787 if (skb == NULL) 788 return -ENOMEM; 789 790 skb_put(skb, LLCP_SEQUENCE_SIZE); 791 792 skb->data[2] = sock->recv_n; 793 794 skb_queue_head(&local->tx_queue, skb); 795 796 return 0; 797} 798