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 pr_debug("Sending DISC\n"); 341 342 local = sock->local; 343 if (local == NULL) 344 return -ENODEV; 345 346 dev = sock->dev; 347 if (dev == NULL) 348 return -ENODEV; 349 350 skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0); 351 if (skb == NULL) 352 return -ENOMEM; 353 354 skb_queue_tail(&local->tx_queue, skb); 355 356 return 0; 357} 358 359int nfc_llcp_send_symm(struct nfc_dev *dev) 360{ 361 struct sk_buff *skb; 362 struct nfc_llcp_local *local; 363 u16 size = 0; 364 int err; 365 366 pr_debug("Sending SYMM\n"); 367 368 local = nfc_llcp_find_local(dev); 369 if (local == NULL) 370 return -ENODEV; 371 372 size += LLCP_HEADER_SIZE; 373 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 374 375 skb = alloc_skb(size, GFP_KERNEL); 376 if (skb == NULL) { 377 err = -ENOMEM; 378 goto out; 379 } 380 381 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 382 383 skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM); 384 385 __net_timestamp(skb); 386 387 nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX); 388 389 err = nfc_data_exchange(dev, local->target_idx, skb, 390 nfc_llcp_recv, local); 391out: 392 nfc_llcp_local_put(local); 393 return err; 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 const u8 *service_name_tlv = NULL; 401 const u8 *miux_tlv = NULL; 402 const u8 *rw_tlv = NULL; 403 u8 service_name_tlv_length = 0; 404 u8 miux_tlv_length, rw_tlv_length, rw; 405 int err; 406 u16 size = 0; 407 __be16 miux; 408 409 pr_debug("Sending CONNECT\n"); 410 411 local = sock->local; 412 if (local == NULL) 413 return -ENODEV; 414 415 if (sock->service_name != NULL) { 416 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN, 417 sock->service_name, 418 sock->service_name_len, 419 &service_name_tlv_length); 420 if (!service_name_tlv) { 421 err = -ENOMEM; 422 goto error_tlv; 423 } 424 size += service_name_tlv_length; 425 } 426 427 /* If the socket parameters are not set, use the local ones */ 428 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ? 429 local->miux : sock->miux; 430 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw; 431 432 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0, 433 &miux_tlv_length); 434 if (!miux_tlv) { 435 err = -ENOMEM; 436 goto error_tlv; 437 } 438 size += miux_tlv_length; 439 440 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length); 441 if (!rw_tlv) { 442 err = -ENOMEM; 443 goto error_tlv; 444 } 445 size += rw_tlv_length; 446 447 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len); 448 449 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size); 450 if (skb == NULL) { 451 err = -ENOMEM; 452 goto error_tlv; 453 } 454 455 llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length); 456 llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 457 llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 458 459 skb_queue_tail(&local->tx_queue, skb); 460 461 err = 0; 462 463error_tlv: 464 if (err) 465 pr_err("error %d\n", err); 466 467 kfree(service_name_tlv); 468 kfree(miux_tlv); 469 kfree(rw_tlv); 470 471 return err; 472} 473 474int nfc_llcp_send_cc(struct nfc_llcp_sock *sock) 475{ 476 struct nfc_llcp_local *local; 477 struct sk_buff *skb; 478 const u8 *miux_tlv = NULL; 479 const u8 *rw_tlv = NULL; 480 u8 miux_tlv_length, rw_tlv_length, rw; 481 int err; 482 u16 size = 0; 483 __be16 miux; 484 485 pr_debug("Sending CC\n"); 486 487 local = sock->local; 488 if (local == NULL) 489 return -ENODEV; 490 491 /* If the socket parameters are not set, use the local ones */ 492 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ? 493 local->miux : sock->miux; 494 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw; 495 496 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0, 497 &miux_tlv_length); 498 if (!miux_tlv) { 499 err = -ENOMEM; 500 goto error_tlv; 501 } 502 size += miux_tlv_length; 503 504 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length); 505 if (!rw_tlv) { 506 err = -ENOMEM; 507 goto error_tlv; 508 } 509 size += rw_tlv_length; 510 511 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size); 512 if (skb == NULL) { 513 err = -ENOMEM; 514 goto error_tlv; 515 } 516 517 llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 518 llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 519 520 skb_queue_tail(&local->tx_queue, skb); 521 522 err = 0; 523 524error_tlv: 525 if (err) 526 pr_err("error %d\n", err); 527 528 kfree(miux_tlv); 529 kfree(rw_tlv); 530 531 return err; 532} 533 534static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local, 535 size_t tlv_length) 536{ 537 struct sk_buff *skb; 538 struct nfc_dev *dev; 539 u16 size = 0; 540 541 if (local == NULL) 542 return ERR_PTR(-ENODEV); 543 544 dev = local->dev; 545 if (dev == NULL) 546 return ERR_PTR(-ENODEV); 547 548 size += LLCP_HEADER_SIZE; 549 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 550 size += tlv_length; 551 552 skb = alloc_skb(size, GFP_KERNEL); 553 if (skb == NULL) 554 return ERR_PTR(-ENOMEM); 555 556 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 557 558 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL); 559 560 return skb; 561} 562 563int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local, 564 struct hlist_head *tlv_list, size_t tlvs_len) 565{ 566 struct nfc_llcp_sdp_tlv *sdp; 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 hlist_for_each_entry_safe(sdp, n, tlv_list, node) { 575 skb_put_data(skb, sdp->tlv, sdp->tlv_len); 576 577 hlist_del(&sdp->node); 578 579 nfc_llcp_free_sdp_tlv(sdp); 580 } 581 582 skb_queue_tail(&local->tx_queue, skb); 583 584 return 0; 585} 586 587int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local, 588 struct hlist_head *tlv_list, size_t tlvs_len) 589{ 590 struct nfc_llcp_sdp_tlv *sdreq; 591 struct hlist_node *n; 592 struct sk_buff *skb; 593 594 skb = nfc_llcp_allocate_snl(local, tlvs_len); 595 if (IS_ERR(skb)) 596 return PTR_ERR(skb); 597 598 mutex_lock(&local->sdreq_lock); 599 600 if (hlist_empty(&local->pending_sdreqs)) 601 mod_timer(&local->sdreq_timer, 602 jiffies + msecs_to_jiffies(3 * local->remote_lto)); 603 604 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) { 605 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri); 606 607 skb_put_data(skb, sdreq->tlv, sdreq->tlv_len); 608 609 hlist_del(&sdreq->node); 610 611 hlist_add_head(&sdreq->node, &local->pending_sdreqs); 612 } 613 614 mutex_unlock(&local->sdreq_lock); 615 616 skb_queue_tail(&local->tx_queue, skb); 617 618 return 0; 619} 620 621int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason) 622{ 623 struct sk_buff *skb; 624 struct nfc_dev *dev; 625 u16 size = 1; /* Reason code */ 626 627 pr_debug("Sending DM reason 0x%x\n", reason); 628 629 if (local == NULL) 630 return -ENODEV; 631 632 dev = local->dev; 633 if (dev == NULL) 634 return -ENODEV; 635 636 size += LLCP_HEADER_SIZE; 637 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 638 639 skb = alloc_skb(size, GFP_KERNEL); 640 if (skb == NULL) 641 return -ENOMEM; 642 643 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 644 645 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM); 646 647 skb_put_data(skb, &reason, 1); 648 649 skb_queue_head(&local->tx_queue, skb); 650 651 return 0; 652} 653 654int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock, 655 struct msghdr *msg, size_t len) 656{ 657 struct sk_buff *pdu; 658 struct sock *sk = &sock->sk; 659 struct nfc_llcp_local *local; 660 size_t frag_len = 0, remaining_len; 661 u8 *msg_data, *msg_ptr; 662 u16 remote_miu; 663 664 pr_debug("Send I frame len %zd\n", len); 665 666 local = sock->local; 667 if (local == NULL) 668 return -ENODEV; 669 670 /* Remote is ready but has not acknowledged our frames */ 671 if((sock->remote_ready && 672 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw && 673 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 674 pr_err("Pending queue is full %d frames\n", 675 skb_queue_len(&sock->tx_pending_queue)); 676 return -ENOBUFS; 677 } 678 679 /* Remote is not ready and we've been queueing enough frames */ 680 if ((!sock->remote_ready && 681 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 682 pr_err("Tx queue is full %d frames\n", 683 skb_queue_len(&sock->tx_queue)); 684 return -ENOBUFS; 685 } 686 687 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN); 688 if (msg_data == NULL) 689 return -ENOMEM; 690 691 if (memcpy_from_msg(msg_data, msg, len)) { 692 kfree(msg_data); 693 return -EFAULT; 694 } 695 696 remaining_len = len; 697 msg_ptr = msg_data; 698 699 do { 700 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 701 LLCP_DEFAULT_MIU : sock->remote_miu; 702 703 frag_len = min_t(size_t, remote_miu, remaining_len); 704 705 pr_debug("Fragment %zd bytes remaining %zd", 706 frag_len, remaining_len); 707 708 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I, 709 frag_len + LLCP_SEQUENCE_SIZE); 710 if (pdu == NULL) { 711 kfree(msg_data); 712 return -ENOMEM; 713 } 714 715 skb_put(pdu, LLCP_SEQUENCE_SIZE); 716 717 if (likely(frag_len > 0)) 718 skb_put_data(pdu, msg_ptr, frag_len); 719 720 skb_queue_tail(&sock->tx_queue, pdu); 721 722 lock_sock(sk); 723 724 nfc_llcp_queue_i_frames(sock); 725 726 release_sock(sk); 727 728 remaining_len -= frag_len; 729 msg_ptr += frag_len; 730 } while (remaining_len > 0); 731 732 kfree(msg_data); 733 734 return len; 735} 736 737int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap, 738 struct msghdr *msg, size_t len) 739{ 740 struct sk_buff *pdu; 741 struct nfc_llcp_local *local; 742 size_t frag_len = 0, remaining_len; 743 u8 *msg_ptr, *msg_data; 744 u16 remote_miu; 745 int err; 746 747 pr_debug("Send UI frame len %zd\n", len); 748 749 local = sock->local; 750 if (local == NULL) 751 return -ENODEV; 752 753 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN); 754 if (msg_data == NULL) 755 return -ENOMEM; 756 757 if (memcpy_from_msg(msg_data, msg, len)) { 758 kfree(msg_data); 759 return -EFAULT; 760 } 761 762 remaining_len = len; 763 msg_ptr = msg_data; 764 765 do { 766 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 767 local->remote_miu : sock->remote_miu; 768 769 frag_len = min_t(size_t, remote_miu, remaining_len); 770 771 pr_debug("Fragment %zd bytes remaining %zd", 772 frag_len, remaining_len); 773 774 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, 0, 775 frag_len + LLCP_HEADER_SIZE, &err); 776 if (pdu == NULL) { 777 pr_err("Could not allocate PDU (error=%d)\n", err); 778 len -= remaining_len; 779 if (len == 0) 780 len = err; 781 break; 782 } 783 784 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI); 785 786 if (likely(frag_len > 0)) 787 skb_put_data(pdu, msg_ptr, frag_len); 788 789 /* No need to check for the peer RW for UI frames */ 790 skb_queue_tail(&local->tx_queue, pdu); 791 792 remaining_len -= frag_len; 793 msg_ptr += frag_len; 794 } while (remaining_len > 0); 795 796 kfree(msg_data); 797 798 return len; 799} 800 801int nfc_llcp_send_rr(struct nfc_llcp_sock *sock) 802{ 803 struct sk_buff *skb; 804 struct nfc_llcp_local *local; 805 806 pr_debug("Send rr nr %d\n", sock->recv_n); 807 808 local = sock->local; 809 if (local == NULL) 810 return -ENODEV; 811 812 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE); 813 if (skb == NULL) 814 return -ENOMEM; 815 816 skb_put(skb, LLCP_SEQUENCE_SIZE); 817 818 skb->data[2] = sock->recv_n; 819 820 skb_queue_head(&local->tx_queue, skb); 821 822 return 0; 823} 824