net/nfc/llcp_commands.c

   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
  18 static 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
  32 static u8 llcp_tlv8(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
  40 static u16 llcp_tlv16(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
  49 static u8 llcp_tlv_version(u8 *tlv)
  50 {
  51         return llcp_tlv8(tlv, LLCP_TLV_VERSION);
  52 }
  53
  54 static u16 llcp_tlv_miux(u8 *tlv)
  55 {
  56         return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
  57 }
  58
  59 static u16 llcp_tlv_wks(u8 *tlv)
  60 {
  61         return llcp_tlv16(tlv, LLCP_TLV_WKS);
  62 }
  63
  64 static u16 llcp_tlv_lto(u8 *tlv)
  65 {
  66         return llcp_tlv8(tlv, LLCP_TLV_LTO);
  67 }
  68
  69 static u8 llcp_tlv_opt(u8 *tlv)
  70 {
  71         return llcp_tlv8(tlv, LLCP_TLV_OPT);
  72 }
  73
  74 static u8 llcp_tlv_rw(u8 *tlv)
  75 {
  76         return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
  77 }
  78
  79 u8 *nfc_llcp_build_tlv(u8 type, 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
 106 struct 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
 133 struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, 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
 174 void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
 175 {
 176         kfree(sdp->tlv);
 177         kfree(sdp);
 178 }
 179
 180 void 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
 192 int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
 193                           u8 *tlv_array, u16 tlv_array_len)
 194 {
 195         u8 *tlv = tlv_array, type, length, offset = 0;
 196
 197         pr_debug("TLV array length %d\n", tlv_array_len);
 198
 199         if (local == NULL)
 200                 return -ENODEV;
 201
 202         while (offset < tlv_array_len) {
 203                 type = tlv[0];
 204                 length = tlv[1];
 205
 206                 pr_debug("type 0x%x length %d\n", type, length);
 207
 208                 switch (type) {
 209                 case LLCP_TLV_VERSION:
 210                         local->remote_version = llcp_tlv_version(tlv);
 211                         break;
 212                 case LLCP_TLV_MIUX:
 213                         local->remote_miu = llcp_tlv_miux(tlv) + 128;
 214                         break;
 215                 case LLCP_TLV_WKS:
 216                         local->remote_wks = llcp_tlv_wks(tlv);
 217                         break;
 218                 case LLCP_TLV_LTO:
 219                         local->remote_lto = llcp_tlv_lto(tlv) * 10;
 220                         break;
 221                 case LLCP_TLV_OPT:
 222                         local->remote_opt = llcp_tlv_opt(tlv);
 223                         break;
 224                 default:
 225                         pr_err("Invalid gt tlv value 0x%x\n", type);
 226                         break;
 227                 }
 228
 229                 offset += length + 2;
 230                 tlv += length + 2;
 231         }
 232
 233         pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
 234                  local->remote_version, local->remote_miu,
 235                  local->remote_lto, local->remote_opt,
 236                  local->remote_wks);
 237
 238         return 0;
 239 }
 240
 241 int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
 242                                   u8 *tlv_array, u16 tlv_array_len)
 243 {
 244         u8 *tlv = tlv_array, type, length, offset = 0;
 245
 246         pr_debug("TLV array length %d\n", tlv_array_len);
 247
 248         if (sock == NULL)
 249                 return -ENOTCONN;
 250
 251         while (offset < tlv_array_len) {
 252                 type = tlv[0];
 253                 length = tlv[1];
 254
 255                 pr_debug("type 0x%x length %d\n", type, length);
 256
 257                 switch (type) {
 258                 case LLCP_TLV_MIUX:
 259                         sock->remote_miu = llcp_tlv_miux(tlv) + 128;
 260                         break;
 261                 case LLCP_TLV_RW:
 262                         sock->remote_rw = llcp_tlv_rw(tlv);
 263                         break;
 264                 case LLCP_TLV_SN:
 265                         break;
 266                 default:
 267                         pr_err("Invalid gt tlv value 0x%x\n", type);
 268                         break;
 269                 }
 270
 271                 offset += length + 2;
 272                 tlv += length + 2;
 273         }
 274
 275         pr_debug("sock %p rw %d miu %d\n", sock,
 276                  sock->remote_rw, sock->remote_miu);
 277
 278         return 0;
 279 }
 280
 281 static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
 282                                        u8 dsap, u8 ssap, u8 ptype)
 283 {
 284         u8 header[2];
 285
 286         pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
 287
 288         header[0] = (u8)((dsap << 2) | (ptype >> 2));
 289         header[1] = (u8)((ptype << 6) | ssap);
 290
 291         pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
 292
 293         skb_put_data(pdu, header, LLCP_HEADER_SIZE);
 294
 295         return pdu;
 296 }
 297
 298 static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
 299                                     u8 tlv_length)
 300 {
 301         /* XXX Add an skb length check */
 302
 303         if (tlv == NULL)
 304                 return NULL;
 305
 306         skb_put_data(pdu, tlv, tlv_length);
 307
 308         return pdu;
 309 }
 310
 311 static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
 312                                          u8 cmd, u16 size)
 313 {
 314         struct sk_buff *skb;
 315         int err;
 316
 317         if (sock->ssap == 0)
 318                 return NULL;
 319
 320         skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
 321                                  size + LLCP_HEADER_SIZE, &err);
 322         if (skb == NULL) {
 323                 pr_err("Could not allocate PDU\n");
 324                 return NULL;
 325         }
 326
 327         skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
 328
 329         return skb;
 330 }
 331
 332 int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
 333 {
 334         struct sk_buff *skb;
 335         struct nfc_dev *dev;
 336         struct nfc_llcp_local *local;
 337
 338         pr_debug("Sending DISC\n");
 339
 340         local = sock->local;
 341         if (local == NULL)
 342                 return -ENODEV;
 343
 344         dev = sock->dev;
 345         if (dev == NULL)
 346                 return -ENODEV;
 347
 348         skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
 349         if (skb == NULL)
 350                 return -ENOMEM;
 351
 352         skb_queue_tail(&local->tx_queue, skb);
 353
 354         return 0;
 355 }
 356
 357 int nfc_llcp_send_symm(struct nfc_dev *dev)
 358 {
 359         struct sk_buff *skb;
 360         struct nfc_llcp_local *local;
 361         u16 size = 0;
 362
 363         pr_debug("Sending SYMM\n");
 364
 365         local = nfc_llcp_find_local(dev);
 366         if (local == NULL)
 367                 return -ENODEV;
 368
 369         size += LLCP_HEADER_SIZE;
 370         size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 371
 372         skb = alloc_skb(size, GFP_KERNEL);
 373         if (skb == NULL)
 374                 return -ENOMEM;
 375
 376         skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 377
 378         skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
 379
 380         __net_timestamp(skb);
 381
 382         nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX);
 383
 384         return nfc_data_exchange(dev, local->target_idx, skb,
 385                                  nfc_llcp_recv, local);
 386 }
 387
 388 int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 389 {
 390         struct nfc_llcp_local *local;
 391         struct sk_buff *skb;
 392         u8 *service_name_tlv = NULL, service_name_tlv_length;
 393         u8 *miux_tlv = NULL, miux_tlv_length;
 394         u8 *rw_tlv = NULL, rw_tlv_length, rw;
 395         int err;
 396         u16 size = 0;
 397         __be16 miux;
 398
 399         pr_debug("Sending CONNECT\n");
 400
 401         local = sock->local;
 402         if (local == NULL)
 403                 return -ENODEV;
 404
 405         if (sock->service_name != NULL) {
 406                 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
 407                                                       sock->service_name,
 408                                                       sock->service_name_len,
 409                                                       &service_name_tlv_length);
 410                 if (!service_name_tlv) {
 411                         err = -ENOMEM;
 412                         goto error_tlv;
 413                 }
 414                 size += service_name_tlv_length;
 415         }
 416
 417         /* If the socket parameters are not set, use the local ones */
 418         miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
 419                 local->miux : sock->miux;
 420         rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
 421
 422         miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
 423                                       &miux_tlv_length);
 424         if (!miux_tlv) {
 425                 err = -ENOMEM;
 426                 goto error_tlv;
 427         }
 428         size += miux_tlv_length;
 429
 430         rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
 431         if (!rw_tlv) {
 432                 err = -ENOMEM;
 433                 goto error_tlv;
 434         }
 435         size += rw_tlv_length;
 436
 437         pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
 438
 439         skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
 440         if (skb == NULL) {
 441                 err = -ENOMEM;
 442                 goto error_tlv;
 443         }
 444
 445         llcp_add_tlv(skb, service_name_tlv, service_name_tlv_length);
 446         llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
 447         llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
 448
 449         skb_queue_tail(&local->tx_queue, skb);
 450
 451         err = 0;
 452
 453 error_tlv:
 454         if (err)
 455                 pr_err("error %d\n", err);
 456
 457         kfree(service_name_tlv);
 458         kfree(miux_tlv);
 459         kfree(rw_tlv);
 460
 461         return err;
 462 }
 463
 464 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 465 {
 466         struct nfc_llcp_local *local;
 467         struct sk_buff *skb;
 468         u8 *miux_tlv = NULL, miux_tlv_length;
 469         u8 *rw_tlv = NULL, rw_tlv_length, rw;
 470         int err;
 471         u16 size = 0;
 472         __be16 miux;
 473
 474         pr_debug("Sending CC\n");
 475
 476         local = sock->local;
 477         if (local == NULL)
 478                 return -ENODEV;
 479
 480         /* If the socket parameters are not set, use the local ones */
 481         miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
 482                 local->miux : sock->miux;
 483         rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
 484
 485         miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
 486                                       &miux_tlv_length);
 487         if (!miux_tlv) {
 488                 err = -ENOMEM;
 489                 goto error_tlv;
 490         }
 491         size += miux_tlv_length;
 492
 493         rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
 494         if (!rw_tlv) {
 495                 err = -ENOMEM;
 496                 goto error_tlv;
 497         }
 498         size += rw_tlv_length;
 499
 500         skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
 501         if (skb == NULL) {
 502                 err = -ENOMEM;
 503                 goto error_tlv;
 504         }
 505
 506         llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
 507         llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
 508
 509         skb_queue_tail(&local->tx_queue, skb);
 510
 511         err = 0;
 512
 513 error_tlv:
 514         if (err)
 515                 pr_err("error %d\n", err);
 516
 517         kfree(miux_tlv);
 518         kfree(rw_tlv);
 519
 520         return err;
 521 }
 522
 523 static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
 524                                              size_t tlv_length)
 525 {
 526         struct sk_buff *skb;
 527         struct nfc_dev *dev;
 528         u16 size = 0;
 529
 530         if (local == NULL)
 531                 return ERR_PTR(-ENODEV);
 532
 533         dev = local->dev;
 534         if (dev == NULL)
 535                 return ERR_PTR(-ENODEV);
 536
 537         size += LLCP_HEADER_SIZE;
 538         size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 539         size += tlv_length;
 540
 541         skb = alloc_skb(size, GFP_KERNEL);
 542         if (skb == NULL)
 543                 return ERR_PTR(-ENOMEM);
 544
 545         skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 546
 547         skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
 548
 549         return skb;
 550 }
 551
 552 int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
 553                             struct hlist_head *tlv_list, size_t tlvs_len)
 554 {
 555         struct nfc_llcp_sdp_tlv *sdp;
 556         struct hlist_node *n;
 557         struct sk_buff *skb;
 558
 559         skb = nfc_llcp_allocate_snl(local, tlvs_len);
 560         if (IS_ERR(skb))
 561                 return PTR_ERR(skb);
 562
 563         hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
 564                 skb_put_data(skb, sdp->tlv, sdp->tlv_len);
 565
 566                 hlist_del(&sdp->node);
 567
 568                 nfc_llcp_free_sdp_tlv(sdp);
 569         }
 570
 571         skb_queue_tail(&local->tx_queue, skb);
 572
 573         return 0;
 574 }
 575
 576 int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
 577                             struct hlist_head *tlv_list, size_t tlvs_len)
 578 {
 579         struct nfc_llcp_sdp_tlv *sdreq;
 580         struct hlist_node *n;
 581         struct sk_buff *skb;
 582
 583         skb = nfc_llcp_allocate_snl(local, tlvs_len);
 584         if (IS_ERR(skb))
 585                 return PTR_ERR(skb);
 586
 587         mutex_lock(&local->sdreq_lock);
 588
 589         if (hlist_empty(&local->pending_sdreqs))
 590                 mod_timer(&local->sdreq_timer,
 591                           jiffies + msecs_to_jiffies(3 * local->remote_lto));
 592
 593         hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
 594                 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
 595
 596                 skb_put_data(skb, sdreq->tlv, sdreq->tlv_len);
 597
 598                 hlist_del(&sdreq->node);
 599
 600                 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
 601         }
 602
 603         mutex_unlock(&local->sdreq_lock);
 604
 605         skb_queue_tail(&local->tx_queue, skb);
 606
 607         return 0;
 608 }
 609
 610 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
 611 {
 612         struct sk_buff *skb;
 613         struct nfc_dev *dev;
 614         u16 size = 1; /* Reason code */
 615
 616         pr_debug("Sending DM reason 0x%x\n", reason);
 617
 618         if (local == NULL)
 619                 return -ENODEV;
 620
 621         dev = local->dev;
 622         if (dev == NULL)
 623                 return -ENODEV;
 624
 625         size += LLCP_HEADER_SIZE;
 626         size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 627
 628         skb = alloc_skb(size, GFP_KERNEL);
 629         if (skb == NULL)
 630                 return -ENOMEM;
 631
 632         skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 633
 634         skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
 635
 636         skb_put_data(skb, &reason, 1);
 637
 638         skb_queue_head(&local->tx_queue, skb);
 639
 640         return 0;
 641 }
 642
 643 int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
 644                           struct msghdr *msg, size_t len)
 645 {
 646         struct sk_buff *pdu;
 647         struct sock *sk = &sock->sk;
 648         struct nfc_llcp_local *local;
 649         size_t frag_len = 0, remaining_len;
 650         u8 *msg_data, *msg_ptr;
 651         u16 remote_miu;
 652
 653         pr_debug("Send I frame len %zd\n", len);
 654
 655         local = sock->local;
 656         if (local == NULL)
 657                 return -ENODEV;
 658
 659         /* Remote is ready but has not acknowledged our frames */
 660         if((sock->remote_ready &&
 661             skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
 662             skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
 663                 pr_err("Pending queue is full %d frames\n",
 664                        skb_queue_len(&sock->tx_pending_queue));
 665                 return -ENOBUFS;
 666         }
 667
 668         /* Remote is not ready and we've been queueing enough frames */
 669         if ((!sock->remote_ready &&
 670              skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
 671                 pr_err("Tx queue is full %d frames\n",
 672                        skb_queue_len(&sock->tx_queue));
 673                 return -ENOBUFS;
 674         }
 675
 676         msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
 677         if (msg_data == NULL)
 678                 return -ENOMEM;
 679
 680         if (memcpy_from_msg(msg_data, msg, len)) {
 681                 kfree(msg_data);
 682                 return -EFAULT;
 683         }
 684
 685         remaining_len = len;
 686         msg_ptr = msg_data;
 687
 688         do {
 689                 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
 690                                 LLCP_DEFAULT_MIU : sock->remote_miu;
 691
 692                 frag_len = min_t(size_t, remote_miu, remaining_len);
 693
 694                 pr_debug("Fragment %zd bytes remaining %zd",
 695                          frag_len, remaining_len);
 696
 697                 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
 698                                         frag_len + LLCP_SEQUENCE_SIZE);
 699                 if (pdu == NULL) {
 700                         kfree(msg_data);
 701                         return -ENOMEM;
 702                 }
 703
 704                 skb_put(pdu, LLCP_SEQUENCE_SIZE);
 705
 706                 if (likely(frag_len > 0))
 707                         skb_put_data(pdu, msg_ptr, frag_len);
 708
 709                 skb_queue_tail(&sock->tx_queue, pdu);
 710
 711                 lock_sock(sk);
 712
 713                 nfc_llcp_queue_i_frames(sock);
 714
 715                 release_sock(sk);
 716
 717                 remaining_len -= frag_len;
 718                 msg_ptr += frag_len;
 719         } while (remaining_len > 0);
 720
 721         kfree(msg_data);
 722
 723         return len;
 724 }
 725
 726 int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
 727                            struct msghdr *msg, size_t len)
 728 {
 729         struct sk_buff *pdu;
 730         struct nfc_llcp_local *local;
 731         size_t frag_len = 0, remaining_len;
 732         u8 *msg_ptr, *msg_data;
 733         u16 remote_miu;
 734         int err;
 735
 736         pr_debug("Send UI frame len %zd\n", len);
 737
 738         local = sock->local;
 739         if (local == NULL)
 740                 return -ENODEV;
 741
 742         msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
 743         if (msg_data == NULL)
 744                 return -ENOMEM;
 745
 746         if (memcpy_from_msg(msg_data, msg, len)) {
 747                 kfree(msg_data);
 748                 return -EFAULT;
 749         }
 750
 751         remaining_len = len;
 752         msg_ptr = msg_data;
 753
 754         do {
 755                 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
 756                                 local->remote_miu : sock->remote_miu;
 757
 758                 frag_len = min_t(size_t, remote_miu, remaining_len);
 759
 760                 pr_debug("Fragment %zd bytes remaining %zd",
 761                          frag_len, remaining_len);
 762
 763                 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, 0,
 764                                          frag_len + LLCP_HEADER_SIZE, &err);
 765                 if (pdu == NULL) {
 766                         pr_err("Could not allocate PDU (error=%d)\n", err);
 767                         len -= remaining_len;
 768                         if (len == 0)
 769                                 len = err;
 770                         break;
 771                 }
 772
 773                 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
 774
 775                 if (likely(frag_len > 0))
 776                         skb_put_data(pdu, msg_ptr, frag_len);
 777
 778                 /* No need to check for the peer RW for UI frames */
 779                 skb_queue_tail(&local->tx_queue, pdu);
 780
 781                 remaining_len -= frag_len;
 782                 msg_ptr += frag_len;
 783         } while (remaining_len > 0);
 784
 785         kfree(msg_data);
 786
 787         return len;
 788 }
 789
 790 int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
 791 {
 792         struct sk_buff *skb;
 793         struct nfc_llcp_local *local;
 794
 795         pr_debug("Send rr nr %d\n", sock->recv_n);
 796
 797         local = sock->local;
 798         if (local == NULL)
 799                 return -ENODEV;
 800
 801         skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
 802         if (skb == NULL)
 803                 return -ENOMEM;
 804
 805         skb_put(skb, LLCP_SEQUENCE_SIZE);
 806
 807         skb->data[2] = sock->recv_n;
 808
 809         skb_queue_head(&local->tx_queue, skb);
 810
 811         return 0;
 812 }