net/nfc/llcp_commands.c

   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->tlv_len is u8, takes uri_len, + 3 for header, + 1 for NULL */
 153         if (WARN_ON_ONCE(uri_len > U8_MAX - 4))
 154                 return NULL;
 155
 156         sdreq = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
 157         if (sdreq == NULL)
 158                 return NULL;
 159
 160         sdreq->tlv_len = uri_len + 3;
 161
 162         if (uri[uri_len - 1] == 0)
 163                 sdreq->tlv_len--;
 164
 165         sdreq->tlv = kzalloc(sdreq->tlv_len + 1, GFP_KERNEL);
 166         if (sdreq->tlv == NULL) {
 167                 kfree(sdreq);
 168                 return NULL;
 169         }
 170
 171         sdreq->tlv[0] = LLCP_TLV_SDREQ;
 172         sdreq->tlv[1] = sdreq->tlv_len - 2;
 173         sdreq->tlv[2] = tid;
 174
 175         sdreq->tid = tid;
 176         sdreq->uri = sdreq->tlv + 3;
 177         memcpy(sdreq->uri, uri, uri_len);
 178
 179         sdreq->time = jiffies;
 180
 181         INIT_HLIST_NODE(&sdreq->node);
 182
 183         return sdreq;
 184 }
 185
 186 void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
 187 {
 188         kfree(sdp->tlv);
 189         kfree(sdp);
 190 }
 191
 192 void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
 193 {
 194         struct nfc_llcp_sdp_tlv *sdp;
 195         struct hlist_node *n;
 196
 197         hlist_for_each_entry_safe(sdp, n, head, node) {
 198                 hlist_del(&sdp->node);
 199
 200                 nfc_llcp_free_sdp_tlv(sdp);
 201         }
 202 }
 203
 204 int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
 205                           u8 *tlv_array, u16 tlv_array_len)
 206 {
 207         u8 *tlv = tlv_array, type, length, offset = 0;
 208
 209         pr_debug("TLV array length %d\n", tlv_array_len);
 210
 211         if (local == NULL)
 212                 return -ENODEV;
 213
 214         while (offset < tlv_array_len) {
 215                 type = tlv[0];
 216                 length = tlv[1];
 217
 218                 pr_debug("type 0x%x length %d\n", type, length);
 219
 220                 switch (type) {
 221                 case LLCP_TLV_VERSION:
 222                         local->remote_version = llcp_tlv_version(tlv);
 223                         break;
 224                 case LLCP_TLV_MIUX:
 225                         local->remote_miu = llcp_tlv_miux(tlv) + 128;
 226                         break;
 227                 case LLCP_TLV_WKS:
 228                         local->remote_wks = llcp_tlv_wks(tlv);
 229                         break;
 230                 case LLCP_TLV_LTO:
 231                         local->remote_lto = llcp_tlv_lto(tlv) * 10;
 232                         break;
 233                 case LLCP_TLV_OPT:
 234                         local->remote_opt = llcp_tlv_opt(tlv);
 235                         break;
 236                 default:
 237                         pr_err("Invalid gt tlv value 0x%x\n", type);
 238                         break;
 239                 }
 240
 241                 offset += length + 2;
 242                 tlv += length + 2;
 243         }
 244
 245         pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
 246                  local->remote_version, local->remote_miu,
 247                  local->remote_lto, local->remote_opt,
 248                  local->remote_wks);
 249
 250         return 0;
 251 }
 252
 253 int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
 254                                   u8 *tlv_array, u16 tlv_array_len)
 255 {
 256         u8 *tlv = tlv_array, type, length, offset = 0;
 257
 258         pr_debug("TLV array length %d\n", tlv_array_len);
 259
 260         if (sock == NULL)
 261                 return -ENOTCONN;
 262
 263         while (offset < tlv_array_len) {
 264                 type = tlv[0];
 265                 length = tlv[1];
 266
 267                 pr_debug("type 0x%x length %d\n", type, length);
 268
 269                 switch (type) {
 270                 case LLCP_TLV_MIUX:
 271                         sock->remote_miu = llcp_tlv_miux(tlv) + 128;
 272                         break;
 273                 case LLCP_TLV_RW:
 274                         sock->remote_rw = llcp_tlv_rw(tlv);
 275                         break;
 276                 case LLCP_TLV_SN:
 277                         break;
 278                 default:
 279                         pr_err("Invalid gt tlv value 0x%x\n", type);
 280                         break;
 281                 }
 282
 283                 offset += length + 2;
 284                 tlv += length + 2;
 285         }
 286
 287         pr_debug("sock %p rw %d miu %d\n", sock,
 288                  sock->remote_rw, sock->remote_miu);
 289
 290         return 0;
 291 }
 292
 293 static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
 294                                        u8 dsap, u8 ssap, u8 ptype)
 295 {
 296         u8 header[2];
 297
 298         pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
 299
 300         header[0] = (u8)((dsap << 2) | (ptype >> 2));
 301         header[1] = (u8)((ptype << 6) | ssap);
 302
 303         pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
 304
 305         memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
 306
 307         return pdu;
 308 }
 309
 310 static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
 311                                     u8 tlv_length)
 312 {
 313         /* XXX Add an skb length check */
 314
 315         if (tlv == NULL)
 316                 return NULL;
 317
 318         memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
 319
 320         return pdu;
 321 }
 322
 323 static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
 324                                          u8 cmd, u16 size)
 325 {
 326         struct sk_buff *skb;
 327         int err;
 328
 329         if (sock->ssap == 0)
 330                 return NULL;
 331
 332         skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
 333                                  size + LLCP_HEADER_SIZE, &err);
 334         if (skb == NULL) {
 335                 pr_err("Could not allocate PDU\n");
 336                 return NULL;
 337         }
 338
 339         skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
 340
 341         return skb;
 342 }
 343
 344 int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
 345 {
 346         struct sk_buff *skb;
 347         struct nfc_dev *dev;
 348         struct nfc_llcp_local *local;
 349
 350         pr_debug("Sending DISC\n");
 351
 352         local = sock->local;
 353         if (local == NULL)
 354                 return -ENODEV;
 355
 356         dev = sock->dev;
 357         if (dev == NULL)
 358                 return -ENODEV;
 359
 360         skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
 361         if (skb == NULL)
 362                 return -ENOMEM;
 363
 364         skb_queue_tail(&local->tx_queue, skb);
 365
 366         return 0;
 367 }
 368
 369 int nfc_llcp_send_symm(struct nfc_dev *dev)
 370 {
 371         struct sk_buff *skb;
 372         struct nfc_llcp_local *local;
 373         u16 size = 0;
 374
 375         pr_debug("Sending SYMM\n");
 376
 377         local = nfc_llcp_find_local(dev);
 378         if (local == NULL)
 379                 return -ENODEV;
 380
 381         size += LLCP_HEADER_SIZE;
 382         size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 383
 384         skb = alloc_skb(size, GFP_KERNEL);
 385         if (skb == NULL)
 386                 return -ENOMEM;
 387
 388         skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 389
 390         skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
 391
 392         __net_timestamp(skb);
 393
 394         nfc_llcp_send_to_raw_sock(local, skb, NFC_DIRECTION_TX);
 395
 396         return nfc_data_exchange(dev, local->target_idx, skb,
 397                                  nfc_llcp_recv, local);
 398 }
 399
 400 int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 401 {
 402         struct nfc_llcp_local *local;
 403         struct sk_buff *skb;
 404         u8 *service_name_tlv = NULL, service_name_tlv_length;
 405         u8 *miux_tlv = NULL, miux_tlv_length;
 406         u8 *rw_tlv = NULL, rw_tlv_length, rw;
 407         int err;
 408         u16 size = 0;
 409         __be16 miux;
 410
 411         pr_debug("Sending CONNECT\n");
 412
 413         local = sock->local;
 414         if (local == NULL)
 415                 return -ENODEV;
 416
 417         if (sock->service_name != NULL) {
 418                 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
 419                                                       sock->service_name,
 420                                                       sock->service_name_len,
 421                                                       &service_name_tlv_length);
 422                 size += service_name_tlv_length;
 423         }
 424
 425         /* If the socket parameters are not set, use the local ones */
 426         miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
 427                 local->miux : sock->miux;
 428         rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
 429
 430         miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
 431                                       &miux_tlv_length);
 432         size += miux_tlv_length;
 433
 434         rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
 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         if (service_name_tlv != NULL)
 446                 skb = llcp_add_tlv(skb, service_name_tlv,
 447                                    service_name_tlv_length);
 448
 449         skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
 450         skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
 451
 452         skb_queue_tail(&local->tx_queue, skb);
 453
 454         return 0;
 455
 456 error_tlv:
 457         pr_err("error %d\n", err);
 458
 459         kfree(service_name_tlv);
 460         kfree(miux_tlv);
 461         kfree(rw_tlv);
 462
 463         return err;
 464 }
 465
 466 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 467 {
 468         struct nfc_llcp_local *local;
 469         struct sk_buff *skb;
 470         u8 *miux_tlv = NULL, miux_tlv_length;
 471         u8 *rw_tlv = NULL, rw_tlv_length, rw;
 472         int err;
 473         u16 size = 0;
 474         __be16 miux;
 475
 476         pr_debug("Sending CC\n");
 477
 478         local = sock->local;
 479         if (local == NULL)
 480                 return -ENODEV;
 481
 482         /* If the socket parameters are not set, use the local ones */
 483         miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
 484                 local->miux : sock->miux;
 485         rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
 486
 487         miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
 488                                       &miux_tlv_length);
 489         size += miux_tlv_length;
 490
 491         rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
 492         size += rw_tlv_length;
 493
 494         skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
 495         if (skb == NULL) {
 496                 err = -ENOMEM;
 497                 goto error_tlv;
 498         }
 499
 500         skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
 501         skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
 502
 503         skb_queue_tail(&local->tx_queue, skb);
 504
 505         return 0;
 506
 507 error_tlv:
 508         pr_err("error %d\n", err);
 509
 510         kfree(miux_tlv);
 511         kfree(rw_tlv);
 512
 513         return err;
 514 }
 515
 516 static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
 517                                              size_t tlv_length)
 518 {
 519         struct sk_buff *skb;
 520         struct nfc_dev *dev;
 521         u16 size = 0;
 522
 523         if (local == NULL)
 524                 return ERR_PTR(-ENODEV);
 525
 526         dev = local->dev;
 527         if (dev == NULL)
 528                 return ERR_PTR(-ENODEV);
 529
 530         size += LLCP_HEADER_SIZE;
 531         size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 532         size += tlv_length;
 533
 534         skb = alloc_skb(size, GFP_KERNEL);
 535         if (skb == NULL)
 536                 return ERR_PTR(-ENOMEM);
 537
 538         skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 539
 540         skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
 541
 542         return skb;
 543 }
 544
 545 int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
 546                             struct hlist_head *tlv_list, size_t tlvs_len)
 547 {
 548         struct nfc_llcp_sdp_tlv *sdp;
 549         struct hlist_node *n;
 550         struct sk_buff *skb;
 551
 552         skb = nfc_llcp_allocate_snl(local, tlvs_len);
 553         if (IS_ERR(skb))
 554                 return PTR_ERR(skb);
 555
 556         hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
 557                 memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len);
 558
 559                 hlist_del(&sdp->node);
 560
 561                 nfc_llcp_free_sdp_tlv(sdp);
 562         }
 563
 564         skb_queue_tail(&local->tx_queue, skb);
 565
 566         return 0;
 567 }
 568
 569 int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
 570                             struct hlist_head *tlv_list, size_t tlvs_len)
 571 {
 572         struct nfc_llcp_sdp_tlv *sdreq;
 573         struct hlist_node *n;
 574         struct sk_buff *skb;
 575
 576         skb = nfc_llcp_allocate_snl(local, tlvs_len);
 577         if (IS_ERR(skb))
 578                 return PTR_ERR(skb);
 579
 580         mutex_lock(&local->sdreq_lock);
 581
 582         if (hlist_empty(&local->pending_sdreqs))
 583                 mod_timer(&local->sdreq_timer,
 584                           jiffies + msecs_to_jiffies(3 * local->remote_lto));
 585
 586         hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
 587                 pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
 588
 589                 memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv,
 590                        sdreq->tlv_len);
 591
 592                 hlist_del(&sdreq->node);
 593
 594                 hlist_add_head(&sdreq->node, &local->pending_sdreqs);
 595         }
 596
 597         mutex_unlock(&local->sdreq_lock);
 598
 599         skb_queue_tail(&local->tx_queue, skb);
 600
 601         return 0;
 602 }
 603
 604 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
 605 {
 606         struct sk_buff *skb;
 607         struct nfc_dev *dev;
 608         u16 size = 1; /* Reason code */
 609
 610         pr_debug("Sending DM reason 0x%x\n", reason);
 611
 612         if (local == NULL)
 613                 return -ENODEV;
 614
 615         dev = local->dev;
 616         if (dev == NULL)
 617                 return -ENODEV;
 618
 619         size += LLCP_HEADER_SIZE;
 620         size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 621
 622         skb = alloc_skb(size, GFP_KERNEL);
 623         if (skb == NULL)
 624                 return -ENOMEM;
 625
 626         skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 627
 628         skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
 629
 630         memcpy(skb_put(skb, 1), &reason, 1);
 631
 632         skb_queue_head(&local->tx_queue, skb);
 633
 634         return 0;
 635 }
 636
 637 int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
 638                           struct msghdr *msg, size_t len)
 639 {
 640         struct sk_buff *pdu;
 641         struct sock *sk = &sock->sk;
 642         struct nfc_llcp_local *local;
 643         size_t frag_len = 0, remaining_len;
 644         u8 *msg_data, *msg_ptr;
 645         u16 remote_miu;
 646
 647         pr_debug("Send I frame len %zd\n", len);
 648
 649         local = sock->local;
 650         if (local == NULL)
 651                 return -ENODEV;
 652
 653         /* Remote is ready but has not acknowledged our frames */
 654         if((sock->remote_ready &&
 655             skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
 656             skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
 657                 pr_err("Pending queue is full %d frames\n",
 658                        skb_queue_len(&sock->tx_pending_queue));
 659                 return -ENOBUFS;
 660         }
 661
 662         /* Remote is not ready and we've been queueing enough frames */
 663         if ((!sock->remote_ready &&
 664              skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
 665                 pr_err("Tx queue is full %d frames\n",
 666                        skb_queue_len(&sock->tx_queue));
 667                 return -ENOBUFS;
 668         }
 669
 670         msg_data = kzalloc(len, GFP_KERNEL);
 671         if (msg_data == NULL)
 672                 return -ENOMEM;
 673
 674         if (memcpy_from_msg(msg_data, msg, len)) {
 675                 kfree(msg_data);
 676                 return -EFAULT;
 677         }
 678
 679         remaining_len = len;
 680         msg_ptr = msg_data;
 681
 682         do {
 683                 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
 684                                 LLCP_DEFAULT_MIU : sock->remote_miu;
 685
 686                 frag_len = min_t(size_t, remote_miu, remaining_len);
 687
 688                 pr_debug("Fragment %zd bytes remaining %zd",
 689                          frag_len, remaining_len);
 690
 691                 pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
 692                                         frag_len + LLCP_SEQUENCE_SIZE);
 693                 if (pdu == NULL) {
 694                         kfree(msg_data);
 695                         return -ENOMEM;
 696                 }
 697
 698                 skb_put(pdu, LLCP_SEQUENCE_SIZE);
 699
 700                 if (likely(frag_len > 0))
 701                         memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
 702
 703                 skb_queue_tail(&sock->tx_queue, pdu);
 704
 705                 lock_sock(sk);
 706
 707                 nfc_llcp_queue_i_frames(sock);
 708
 709                 release_sock(sk);
 710
 711                 remaining_len -= frag_len;
 712                 msg_ptr += frag_len;
 713         } while (remaining_len > 0);
 714
 715         kfree(msg_data);
 716
 717         return len;
 718 }
 719
 720 int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
 721                            struct msghdr *msg, size_t len)
 722 {
 723         struct sk_buff *pdu;
 724         struct nfc_llcp_local *local;
 725         size_t frag_len = 0, remaining_len;
 726         u8 *msg_ptr, *msg_data;
 727         u16 remote_miu;
 728         int err;
 729
 730         pr_debug("Send UI frame len %zd\n", len);
 731
 732         local = sock->local;
 733         if (local == NULL)
 734                 return -ENODEV;
 735
 736         msg_data = kzalloc(len, GFP_KERNEL);
 737         if (msg_data == NULL)
 738                 return -ENOMEM;
 739
 740         if (memcpy_from_msg(msg_data, msg, len)) {
 741                 kfree(msg_data);
 742                 return -EFAULT;
 743         }
 744
 745         remaining_len = len;
 746         msg_ptr = msg_data;
 747
 748         do {
 749                 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
 750                                 local->remote_miu : sock->remote_miu;
 751
 752                 frag_len = min_t(size_t, remote_miu, remaining_len);
 753
 754                 pr_debug("Fragment %zd bytes remaining %zd",
 755                          frag_len, remaining_len);
 756
 757                 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, 0,
 758                                          frag_len + LLCP_HEADER_SIZE, &err);
 759                 if (pdu == NULL) {
 760                         pr_err("Could not allocate PDU (error=%d)\n", err);
 761                         len -= remaining_len;
 762                         if (len == 0)
 763                                 len = err;
 764                         break;
 765                 }
 766
 767                 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
 768
 769                 if (likely(frag_len > 0))
 770                         memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
 771
 772                 /* No need to check for the peer RW for UI frames */
 773                 skb_queue_tail(&local->tx_queue, pdu);
 774
 775                 remaining_len -= frag_len;
 776                 msg_ptr += frag_len;
 777         } while (remaining_len > 0);
 778
 779         kfree(msg_data);
 780
 781         return len;
 782 }
 783
 784 int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
 785 {
 786         struct sk_buff *skb;
 787         struct nfc_llcp_local *local;
 788
 789         pr_debug("Send rr nr %d\n", sock->recv_n);
 790
 791         local = sock->local;
 792         if (local == NULL)
 793                 return -ENODEV;
 794
 795         skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
 796         if (skb == NULL)
 797                 return -ENOMEM;
 798
 799         skb_put(skb, LLCP_SEQUENCE_SIZE);
 800
 801         skb->data[2] = sock->recv_n;
 802
 803         skb_queue_head(&local->tx_queue, skb);
 804
 805         return 0;
 806 }