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 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 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 61 static u8 llcp_tlv_version(u8 *tlv) 62 { 63 return llcp_tlv8(tlv, LLCP_TLV_VERSION); 64 } 65 66 static u16 llcp_tlv_miux(u8 *tlv) 67 { 68 return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff; 69 } 70 71 static u16 llcp_tlv_wks(u8 *tlv) 72 { 73 return llcp_tlv16(tlv, LLCP_TLV_WKS); 74 } 75 76 static u16 llcp_tlv_lto(u8 *tlv) 77 { 78 return llcp_tlv8(tlv, LLCP_TLV_LTO); 79 } 80 81 static u8 llcp_tlv_opt(u8 *tlv) 82 { 83 return llcp_tlv8(tlv, LLCP_TLV_OPT); 84 } 85 86 static u8 llcp_tlv_rw(u8 *tlv) 87 { 88 return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf; 89 } 90 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 } 117 118 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 } 144 145 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 = 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 } 181 182 void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp) 183 { 184 kfree(sdp->tlv); 185 kfree(sdp); 186 } 187 188 void 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 } 199 200 int 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 } 248 249 int 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 } 288 289 static 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 } 305 306 static 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 } 318 319 static 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 } 339 340 int 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 } 364 365 int 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 } 395 396 int 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; 405 __be16 miux; 406 407 pr_debug("Sending CONNECT\n"); 408 409 local = sock->local; 410 if (local == NULL) 411 return -ENODEV; 412 413 if (sock->service_name != NULL) { 414 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN, 415 sock->service_name, 416 sock->service_name_len, 417 &service_name_tlv_length); 418 size += service_name_tlv_length; 419 } 420 421 /* If the socket parameters are not set, use the local ones */ 422 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ? 423 local->miux : sock->miux; 424 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw; 425 426 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0, 427 &miux_tlv_length); 428 size += miux_tlv_length; 429 430 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length); 431 size += rw_tlv_length; 432 433 pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len); 434 435 skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size); 436 if (skb == NULL) { 437 err = -ENOMEM; 438 goto error_tlv; 439 } 440 441 if (service_name_tlv != NULL) 442 skb = llcp_add_tlv(skb, service_name_tlv, 443 service_name_tlv_length); 444 445 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 446 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 447 448 skb_queue_tail(&local->tx_queue, skb); 449 450 return 0; 451 452 error_tlv: 453 pr_err("error %d\n", err); 454 455 kfree(service_name_tlv); 456 kfree(miux_tlv); 457 kfree(rw_tlv); 458 459 return err; 460 } 461 462 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock) 463 { 464 struct nfc_llcp_local *local; 465 struct sk_buff *skb; 466 u8 *miux_tlv = NULL, miux_tlv_length; 467 u8 *rw_tlv = NULL, rw_tlv_length, rw; 468 int err; 469 u16 size = 0; 470 __be16 miux; 471 472 pr_debug("Sending CC\n"); 473 474 local = sock->local; 475 if (local == NULL) 476 return -ENODEV; 477 478 /* If the socket parameters are not set, use the local ones */ 479 miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ? 480 local->miux : sock->miux; 481 rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw; 482 483 miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0, 484 &miux_tlv_length); 485 size += miux_tlv_length; 486 487 rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length); 488 size += rw_tlv_length; 489 490 skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size); 491 if (skb == NULL) { 492 err = -ENOMEM; 493 goto error_tlv; 494 } 495 496 skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 497 skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 498 499 skb_queue_tail(&local->tx_queue, skb); 500 501 return 0; 502 503 error_tlv: 504 pr_err("error %d\n", err); 505 506 kfree(miux_tlv); 507 kfree(rw_tlv); 508 509 return err; 510 } 511 512 static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local, 513 size_t tlv_length) 514 { 515 struct sk_buff *skb; 516 struct nfc_dev *dev; 517 u16 size = 0; 518 519 if (local == NULL) 520 return ERR_PTR(-ENODEV); 521 522 dev = local->dev; 523 if (dev == NULL) 524 return ERR_PTR(-ENODEV); 525 526 size += LLCP_HEADER_SIZE; 527 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 528 size += tlv_length; 529 530 skb = alloc_skb(size, GFP_KERNEL); 531 if (skb == NULL) 532 return ERR_PTR(-ENOMEM); 533 534 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 535 536 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL); 537 538 return skb; 539 } 540 541 int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local, 542 struct hlist_head *tlv_list, size_t tlvs_len) 543 { 544 struct nfc_llcp_sdp_tlv *sdp; 545 struct hlist_node *n; 546 struct sk_buff *skb; 547 548 skb = nfc_llcp_allocate_snl(local, tlvs_len); 549 if (IS_ERR(skb)) 550 return PTR_ERR(skb); 551 552 hlist_for_each_entry_safe(sdp, n, tlv_list, node) { 553 memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len); 554 555 hlist_del(&sdp->node); 556 557 nfc_llcp_free_sdp_tlv(sdp); 558 } 559 560 skb_queue_tail(&local->tx_queue, skb); 561 562 return 0; 563 } 564 565 int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local, 566 struct hlist_head *tlv_list, size_t tlvs_len) 567 { 568 struct nfc_llcp_sdp_tlv *sdreq; 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 mutex_lock(&local->sdreq_lock); 577 578 if (hlist_empty(&local->pending_sdreqs)) 579 mod_timer(&local->sdreq_timer, 580 jiffies + msecs_to_jiffies(3 * local->remote_lto)); 581 582 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) { 583 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri); 584 585 memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv, 586 sdreq->tlv_len); 587 588 hlist_del(&sdreq->node); 589 590 hlist_add_head(&sdreq->node, &local->pending_sdreqs); 591 } 592 593 mutex_unlock(&local->sdreq_lock); 594 595 skb_queue_tail(&local->tx_queue, skb); 596 597 return 0; 598 } 599 600 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason) 601 { 602 struct sk_buff *skb; 603 struct nfc_dev *dev; 604 u16 size = 1; /* Reason code */ 605 606 pr_debug("Sending DM reason 0x%x\n", reason); 607 608 if (local == NULL) 609 return -ENODEV; 610 611 dev = local->dev; 612 if (dev == NULL) 613 return -ENODEV; 614 615 size += LLCP_HEADER_SIZE; 616 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 617 618 skb = alloc_skb(size, GFP_KERNEL); 619 if (skb == NULL) 620 return -ENOMEM; 621 622 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 623 624 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM); 625 626 memcpy(skb_put(skb, 1), &reason, 1); 627 628 skb_queue_head(&local->tx_queue, skb); 629 630 return 0; 631 } 632 633 int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock, 634 struct msghdr *msg, size_t len) 635 { 636 struct sk_buff *pdu; 637 struct sock *sk = &sock->sk; 638 struct nfc_llcp_local *local; 639 size_t frag_len = 0, remaining_len; 640 u8 *msg_data, *msg_ptr; 641 u16 remote_miu; 642 643 pr_debug("Send I frame len %zd\n", len); 644 645 local = sock->local; 646 if (local == NULL) 647 return -ENODEV; 648 649 /* Remote is ready but has not acknowledged our frames */ 650 if((sock->remote_ready && 651 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw && 652 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 653 pr_err("Pending queue is full %d frames\n", 654 skb_queue_len(&sock->tx_pending_queue)); 655 return -ENOBUFS; 656 } 657 658 /* Remote is not ready and we've been queueing enough frames */ 659 if ((!sock->remote_ready && 660 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 661 pr_err("Tx queue is full %d frames\n", 662 skb_queue_len(&sock->tx_queue)); 663 return -ENOBUFS; 664 } 665 666 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN); 667 if (msg_data == NULL) 668 return -ENOMEM; 669 670 if (memcpy_from_msg(msg_data, msg, len)) { 671 kfree(msg_data); 672 return -EFAULT; 673 } 674 675 remaining_len = len; 676 msg_ptr = msg_data; 677 678 do { 679 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 680 LLCP_DEFAULT_MIU : sock->remote_miu; 681 682 frag_len = min_t(size_t, remote_miu, remaining_len); 683 684 pr_debug("Fragment %zd bytes remaining %zd", 685 frag_len, remaining_len); 686 687 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I, 688 frag_len + LLCP_SEQUENCE_SIZE); 689 if (pdu == NULL) { 690 kfree(msg_data); 691 return -ENOMEM; 692 } 693 694 skb_put(pdu, LLCP_SEQUENCE_SIZE); 695 696 if (likely(frag_len > 0)) 697 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len); 698 699 skb_queue_tail(&sock->tx_queue, pdu); 700 701 lock_sock(sk); 702 703 nfc_llcp_queue_i_frames(sock); 704 705 release_sock(sk); 706 707 remaining_len -= frag_len; 708 msg_ptr += frag_len; 709 } while (remaining_len > 0); 710 711 kfree(msg_data); 712 713 return len; 714 } 715 716 int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap, 717 struct msghdr *msg, size_t len) 718 { 719 struct sk_buff *pdu; 720 struct nfc_llcp_local *local; 721 size_t frag_len = 0, remaining_len; 722 u8 *msg_ptr, *msg_data; 723 u16 remote_miu; 724 int err; 725 726 pr_debug("Send UI frame len %zd\n", len); 727 728 local = sock->local; 729 if (local == NULL) 730 return -ENODEV; 731 732 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN); 733 if (msg_data == NULL) 734 return -ENOMEM; 735 736 if (memcpy_from_msg(msg_data, msg, len)) { 737 kfree(msg_data); 738 return -EFAULT; 739 } 740 741 remaining_len = len; 742 msg_ptr = msg_data; 743 744 do { 745 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 746 local->remote_miu : sock->remote_miu; 747 748 frag_len = min_t(size_t, remote_miu, remaining_len); 749 750 pr_debug("Fragment %zd bytes remaining %zd", 751 frag_len, remaining_len); 752 753 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT, 754 frag_len + LLCP_HEADER_SIZE, &err); 755 if (pdu == NULL) { 756 pr_err("Could not allocate PDU\n"); 757 continue; 758 } 759 760 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI); 761 762 if (likely(frag_len > 0)) 763 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len); 764 765 /* No need to check for the peer RW for UI frames */ 766 skb_queue_tail(&local->tx_queue, pdu); 767 768 remaining_len -= frag_len; 769 msg_ptr += frag_len; 770 } while (remaining_len > 0); 771 772 kfree(msg_data); 773 774 return len; 775 } 776 777 int nfc_llcp_send_rr(struct nfc_llcp_sock *sock) 778 { 779 struct sk_buff *skb; 780 struct nfc_llcp_local *local; 781 782 pr_debug("Send rr nr %d\n", sock->recv_n); 783 784 local = sock->local; 785 if (local == NULL) 786 return -ENODEV; 787 788 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE); 789 if (skb == NULL) 790 return -ENOMEM; 791 792 skb_put(skb, LLCP_SEQUENCE_SIZE); 793 794 skb->data[2] = sock->recv_n; 795 796 skb_queue_head(&local->tx_queue, skb); 797 798 return 0; 799 } 800