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 llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length); 442 llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 443 llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 444 445 skb_queue_tail(&local->tx_queue, skb); 446 447 err = 0; 448 449 error_tlv: 450 if (err) 451 pr_err("error %d\n", err); 452 453 kfree(service_name_tlv); 454 kfree(miux_tlv); 455 kfree(rw_tlv); 456 457 return err; 458 } 459 460 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock) 461 { 462 struct nfc_llcp_local *local; 463 struct sk_buff *skb; 464 u8 *miux_tlv = NULL, miux_tlv_length; 465 u8 *rw_tlv = NULL, rw_tlv_length, rw; 466 int err; 467 u16 size = 0; 468 __be16 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 llcp_add_tlv(skb, miux_tlv, miux_tlv_length); 495 llcp_add_tlv(skb, rw_tlv, rw_tlv_length); 496 497 skb_queue_tail(&local->tx_queue, skb); 498 499 err = 0; 500 501 error_tlv: 502 if (err) 503 pr_err("error %d\n", err); 504 505 kfree(miux_tlv); 506 kfree(rw_tlv); 507 508 return err; 509 } 510 511 static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local, 512 size_t tlv_length) 513 { 514 struct sk_buff *skb; 515 struct nfc_dev *dev; 516 u16 size = 0; 517 518 if (local == NULL) 519 return ERR_PTR(-ENODEV); 520 521 dev = local->dev; 522 if (dev == NULL) 523 return ERR_PTR(-ENODEV); 524 525 size += LLCP_HEADER_SIZE; 526 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 527 size += tlv_length; 528 529 skb = alloc_skb(size, GFP_KERNEL); 530 if (skb == NULL) 531 return ERR_PTR(-ENOMEM); 532 533 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 534 535 skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL); 536 537 return skb; 538 } 539 540 int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local, 541 struct hlist_head *tlv_list, size_t tlvs_len) 542 { 543 struct nfc_llcp_sdp_tlv *sdp; 544 struct hlist_node *n; 545 struct sk_buff *skb; 546 547 skb = nfc_llcp_allocate_snl(local, tlvs_len); 548 if (IS_ERR(skb)) 549 return PTR_ERR(skb); 550 551 hlist_for_each_entry_safe(sdp, n, tlv_list, node) { 552 memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len); 553 554 hlist_del(&sdp->node); 555 556 nfc_llcp_free_sdp_tlv(sdp); 557 } 558 559 skb_queue_tail(&local->tx_queue, skb); 560 561 return 0; 562 } 563 564 int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local, 565 struct hlist_head *tlv_list, size_t tlvs_len) 566 { 567 struct nfc_llcp_sdp_tlv *sdreq; 568 struct hlist_node *n; 569 struct sk_buff *skb; 570 571 skb = nfc_llcp_allocate_snl(local, tlvs_len); 572 if (IS_ERR(skb)) 573 return PTR_ERR(skb); 574 575 mutex_lock(&local->sdreq_lock); 576 577 if (hlist_empty(&local->pending_sdreqs)) 578 mod_timer(&local->sdreq_timer, 579 jiffies + msecs_to_jiffies(3 * local->remote_lto)); 580 581 hlist_for_each_entry_safe(sdreq, n, tlv_list, node) { 582 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri); 583 584 memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv, 585 sdreq->tlv_len); 586 587 hlist_del(&sdreq->node); 588 589 hlist_add_head(&sdreq->node, &local->pending_sdreqs); 590 } 591 592 mutex_unlock(&local->sdreq_lock); 593 594 skb_queue_tail(&local->tx_queue, skb); 595 596 return 0; 597 } 598 599 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason) 600 { 601 struct sk_buff *skb; 602 struct nfc_dev *dev; 603 u16 size = 1; /* Reason code */ 604 605 pr_debug("Sending DM reason 0x%x\n", reason); 606 607 if (local == NULL) 608 return -ENODEV; 609 610 dev = local->dev; 611 if (dev == NULL) 612 return -ENODEV; 613 614 size += LLCP_HEADER_SIZE; 615 size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 616 617 skb = alloc_skb(size, GFP_KERNEL); 618 if (skb == NULL) 619 return -ENOMEM; 620 621 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 622 623 skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM); 624 625 memcpy(skb_put(skb, 1), &reason, 1); 626 627 skb_queue_head(&local->tx_queue, skb); 628 629 return 0; 630 } 631 632 int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock, 633 struct msghdr *msg, size_t len) 634 { 635 struct sk_buff *pdu; 636 struct sock *sk = &sock->sk; 637 struct nfc_llcp_local *local; 638 size_t frag_len = 0, remaining_len; 639 u8 *msg_data, *msg_ptr; 640 u16 remote_miu; 641 642 pr_debug("Send I frame len %zd\n", len); 643 644 local = sock->local; 645 if (local == NULL) 646 return -ENODEV; 647 648 /* Remote is ready but has not acknowledged our frames */ 649 if((sock->remote_ready && 650 skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw && 651 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 652 pr_err("Pending queue is full %d frames\n", 653 skb_queue_len(&sock->tx_pending_queue)); 654 return -ENOBUFS; 655 } 656 657 /* Remote is not ready and we've been queueing enough frames */ 658 if ((!sock->remote_ready && 659 skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) { 660 pr_err("Tx queue is full %d frames\n", 661 skb_queue_len(&sock->tx_queue)); 662 return -ENOBUFS; 663 } 664 665 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN); 666 if (msg_data == NULL) 667 return -ENOMEM; 668 669 if (memcpy_from_msg(msg_data, msg, len)) { 670 kfree(msg_data); 671 return -EFAULT; 672 } 673 674 remaining_len = len; 675 msg_ptr = msg_data; 676 677 do { 678 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 679 LLCP_DEFAULT_MIU : sock->remote_miu; 680 681 frag_len = min_t(size_t, remote_miu, remaining_len); 682 683 pr_debug("Fragment %zd bytes remaining %zd", 684 frag_len, remaining_len); 685 686 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I, 687 frag_len + LLCP_SEQUENCE_SIZE); 688 if (pdu == NULL) { 689 kfree(msg_data); 690 return -ENOMEM; 691 } 692 693 skb_put(pdu, LLCP_SEQUENCE_SIZE); 694 695 if (likely(frag_len > 0)) 696 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len); 697 698 skb_queue_tail(&sock->tx_queue, pdu); 699 700 lock_sock(sk); 701 702 nfc_llcp_queue_i_frames(sock); 703 704 release_sock(sk); 705 706 remaining_len -= frag_len; 707 msg_ptr += frag_len; 708 } while (remaining_len > 0); 709 710 kfree(msg_data); 711 712 return len; 713 } 714 715 int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap, 716 struct msghdr *msg, size_t len) 717 { 718 struct sk_buff *pdu; 719 struct nfc_llcp_local *local; 720 size_t frag_len = 0, remaining_len; 721 u8 *msg_ptr, *msg_data; 722 u16 remote_miu; 723 int err; 724 725 pr_debug("Send UI frame len %zd\n", len); 726 727 local = sock->local; 728 if (local == NULL) 729 return -ENODEV; 730 731 msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN); 732 if (msg_data == NULL) 733 return -ENOMEM; 734 735 if (memcpy_from_msg(msg_data, msg, len)) { 736 kfree(msg_data); 737 return -EFAULT; 738 } 739 740 remaining_len = len; 741 msg_ptr = msg_data; 742 743 do { 744 remote_miu = sock->remote_miu > LLCP_MAX_MIU ? 745 local->remote_miu : sock->remote_miu; 746 747 frag_len = min_t(size_t, remote_miu, remaining_len); 748 749 pr_debug("Fragment %zd bytes remaining %zd", 750 frag_len, remaining_len); 751 752 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT, 753 frag_len + LLCP_HEADER_SIZE, &err); 754 if (pdu == NULL) { 755 pr_err("Could not allocate PDU\n"); 756 continue; 757 } 758 759 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI); 760 761 if (likely(frag_len > 0)) 762 memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len); 763 764 /* No need to check for the peer RW for UI frames */ 765 skb_queue_tail(&local->tx_queue, pdu); 766 767 remaining_len -= frag_len; 768 msg_ptr += frag_len; 769 } while (remaining_len > 0); 770 771 kfree(msg_data); 772 773 return len; 774 } 775 776 int nfc_llcp_send_rr(struct nfc_llcp_sock *sock) 777 { 778 struct sk_buff *skb; 779 struct nfc_llcp_local *local; 780 781 pr_debug("Send rr nr %d\n", sock->recv_n); 782 783 local = sock->local; 784 if (local == NULL) 785 return -ENODEV; 786 787 skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE); 788 if (skb == NULL) 789 return -ENOMEM; 790 791 skb_put(skb, LLCP_SEQUENCE_SIZE); 792 793 skb->data[2] = sock->recv_n; 794 795 skb_queue_head(&local->tx_queue, skb); 796 797 return 0; 798 } 799