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, write to the
  16  * Free Software Foundation, Inc.,
  17  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 #define pr_fmt(fmt) "llcp: %s: " fmt, __func__
  21
  22 #include <linux/init.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/nfc.h>
  26
  27 #include <net/nfc/nfc.h>
  28
  29 #include "nfc.h"
  30 #include "llcp.h"
  31
  32 static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
  33         0,
  34         1, /* VERSION */
  35         2, /* MIUX */
  36         2, /* WKS */
  37         1, /* LTO */
  38         1, /* RW */
  39         0, /* SN */
  40         1, /* OPT */
  41         0, /* SDREQ */
  42         2, /* SDRES */
  43
  44 };
  45
  46 static u8 llcp_tlv8(u8 *tlv, u8 type)
  47 {
  48         if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
  49                 return 0;
  50
  51         return tlv[2];
  52 }
  53
  54 static u16 llcp_tlv16(u8 *tlv, u8 type)
  55 {
  56         if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
  57                 return 0;
  58
  59         return be16_to_cpu(*((__be16 *)(tlv + 2)));
  60 }
  61
  62
  63 static u8 llcp_tlv_version(u8 *tlv)
  64 {
  65         return llcp_tlv8(tlv, LLCP_TLV_VERSION);
  66 }
  67
  68 static u16 llcp_tlv_miux(u8 *tlv)
  69 {
  70         return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
  71 }
  72
  73 static u16 llcp_tlv_wks(u8 *tlv)
  74 {
  75         return llcp_tlv16(tlv, LLCP_TLV_WKS);
  76 }
  77
  78 static u16 llcp_tlv_lto(u8 *tlv)
  79 {
  80         return llcp_tlv8(tlv, LLCP_TLV_LTO);
  81 }
  82
  83 static u8 llcp_tlv_opt(u8 *tlv)
  84 {
  85         return llcp_tlv8(tlv, LLCP_TLV_OPT);
  86 }
  87
  88 static u8 llcp_tlv_rw(u8 *tlv)
  89 {
  90         return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
  91 }
  92
  93 u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
  94 {
  95         u8 *tlv, length;
  96
  97         pr_debug("type %d\n", type);
  98
  99         if (type >= LLCP_TLV_MAX)
 100                 return NULL;
 101
 102         length = llcp_tlv_length[type];
 103         if (length == 0 && value_length == 0)
 104                 return NULL;
 105         else if (length == 0)
 106                 length = value_length;
 107
 108         *tlv_length = 2 + length;
 109         tlv = kzalloc(2 + length, GFP_KERNEL);
 110         if (tlv == NULL)
 111                 return tlv;
 112
 113         tlv[0] = type;
 114         tlv[1] = length;
 115         memcpy(tlv + 2, value, length);
 116
 117         return tlv;
 118 }
 119
 120 struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdres_tlv(u8 tid, u8 sap)
 121 {
 122         struct nfc_llcp_sdp_tlv *sdres;
 123         u8 value[2];
 124
 125         sdres = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
 126         if (sdres == NULL)
 127                 return NULL;
 128
 129         value[0] = tid;
 130         value[1] = sap;
 131
 132         sdres->tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, value, 2,
 133                                         &sdres->tlv_len);
 134         if (sdres->tlv == NULL) {
 135                 kfree(sdres);
 136                 return NULL;
 137         }
 138
 139         sdres->tid = tid;
 140         sdres->sap = sap;
 141
 142         INIT_HLIST_NODE(&sdres->node);
 143
 144         return sdres;
 145 }
 146
 147 struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, char *uri,
 148                                                   size_t uri_len)
 149 {
 150         struct nfc_llcp_sdp_tlv *sdreq;
 151
 152         pr_debug("uri: %s, len: %zu\n", uri, uri_len);
 153
 154         sdreq = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
 155         if (sdreq == NULL)
 156                 return NULL;
 157
 158         sdreq->tlv_len = uri_len + 3;
 159
 160         if (uri[uri_len - 1] == 0)
 161                 sdreq->tlv_len--;
 162
 163         sdreq->tlv = kzalloc(sdreq->tlv_len + 1, GFP_KERNEL);
 164         if (sdreq->tlv == NULL) {
 165                 kfree(sdreq);
 166                 return NULL;
 167         }
 168
 169         sdreq->tlv[0] = LLCP_TLV_SDREQ;
 170         sdreq->tlv[1] = sdreq->tlv_len - 2;
 171         sdreq->tlv[2] = tid;
 172
 173         sdreq->tid = tid;
 174         sdreq->uri = sdreq->tlv + 3;
 175         memcpy(sdreq->uri, uri, uri_len);
 176
 177         sdreq->time = jiffies;
 178
 179         INIT_HLIST_NODE(&sdreq->node);
 180
 181         return sdreq;
 182 }
 183
 184 void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
 185 {
 186         kfree(sdp->tlv);
 187         kfree(sdp);
 188 }
 189
 190 void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
 191 {
 192         struct nfc_llcp_sdp_tlv *sdp;
 193         struct hlist_node *n;
 194
 195         hlist_for_each_entry_safe(sdp, n, head, node) {
 196                 hlist_del(&sdp->node);
 197
 198                 nfc_llcp_free_sdp_tlv(sdp);
 199         }
 200 }
 201
 202 int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
 203                           u8 *tlv_array, u16 tlv_array_len)
 204 {
 205         u8 *tlv = tlv_array, type, length, offset = 0;
 206
 207         pr_debug("TLV array length %d\n", tlv_array_len);
 208
 209         if (local == NULL)
 210                 return -ENODEV;
 211
 212         while (offset < tlv_array_len) {
 213                 type = tlv[0];
 214                 length = tlv[1];
 215
 216                 pr_debug("type 0x%x length %d\n", type, length);
 217
 218                 switch (type) {
 219                 case LLCP_TLV_VERSION:
 220                         local->remote_version = llcp_tlv_version(tlv);
 221                         break;
 222                 case LLCP_TLV_MIUX:
 223                         local->remote_miu = llcp_tlv_miux(tlv) + 128;
 224                         break;
 225                 case LLCP_TLV_WKS:
 226                         local->remote_wks = llcp_tlv_wks(tlv);
 227                         break;
 228                 case LLCP_TLV_LTO:
 229                         local->remote_lto = llcp_tlv_lto(tlv) * 10;
 230                         break;
 231                 case LLCP_TLV_OPT:
 232                         local->remote_opt = llcp_tlv_opt(tlv);
 233                         break;
 234                 default:
 235                         pr_err("Invalid gt tlv value 0x%x\n", type);
 236                         break;
 237                 }
 238
 239                 offset += length + 2;
 240                 tlv += length + 2;
 241         }
 242
 243         pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
 244                  local->remote_version, local->remote_miu,
 245                  local->remote_lto, local->remote_opt,
 246                  local->remote_wks);
 247
 248         return 0;
 249 }
 250
 251 int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
 252                                   u8 *tlv_array, u16 tlv_array_len)
 253 {
 254         u8 *tlv = tlv_array, type, length, offset = 0;
 255
 256         pr_debug("TLV array length %d\n", tlv_array_len);
 257
 258         if (sock == NULL)
 259                 return -ENOTCONN;
 260
 261         while (offset < tlv_array_len) {
 262                 type = tlv[0];
 263                 length = tlv[1];
 264
 265                 pr_debug("type 0x%x length %d\n", type, length);
 266
 267                 switch (type) {
 268                 case LLCP_TLV_MIUX:
 269                         sock->remote_miu = llcp_tlv_miux(tlv) + 128;
 270                         break;
 271                 case LLCP_TLV_RW:
 272                         sock->remote_rw = llcp_tlv_rw(tlv);
 273                         break;
 274                 case LLCP_TLV_SN:
 275                         break;
 276                 default:
 277                         pr_err("Invalid gt tlv value 0x%x\n", type);
 278                         break;
 279                 }
 280
 281                 offset += length + 2;
 282                 tlv += length + 2;
 283         }
 284
 285         pr_debug("sock %p rw %d miu %d\n", sock,
 286                  sock->remote_rw, sock->remote_miu);
 287
 288         return 0;
 289 }
 290
 291 static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
 292                                        u8 dsap, u8 ssap, u8 ptype)
 293 {
 294         u8 header[2];
 295
 296         pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
 297
 298         header[0] = (u8)((dsap << 2) | (ptype >> 2));
 299         header[1] = (u8)((ptype << 6) | ssap);
 300
 301         pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
 302
 303         memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
 304
 305         return pdu;
 306 }
 307
 308 static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
 309                                     u8 tlv_length)
 310 {
 311         /* XXX Add an skb length check */
 312
 313         if (tlv == NULL)
 314                 return NULL;
 315
 316         memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
 317
 318         return pdu;
 319 }
 320
 321 static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
 322                                          u8 cmd, u16 size)
 323 {
 324         struct sk_buff *skb;
 325         int err;
 326
 327         if (sock->ssap == 0)
 328                 return NULL;
 329
 330         skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
 331                                  size + LLCP_HEADER_SIZE, &err);
 332         if (skb == NULL) {
 333                 pr_err("Could not allocate PDU\n");
 334                 return NULL;
 335         }
 336
 337         skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
 338
 339         return skb;
 340 }
 341
 342 int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
 343 {
 344         struct sk_buff *skb;
 345         struct nfc_dev *dev;
 346         struct nfc_llcp_local *local;
 347
 348         pr_debug("Sending DISC\n");
 349
 350         local = sock->local;
 351         if (local == NULL)
 352                 return -ENODEV;
 353
 354         dev = sock->dev;
 355         if (dev == NULL)
 356                 return -ENODEV;
 357
 358         skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
 359         if (skb == NULL)
 360                 return -ENOMEM;
 361
 362         skb_queue_tail(&local->tx_queue, skb);
 363
 364         return 0;
 365 }
 366
 367 int nfc_llcp_send_symm(struct nfc_dev *dev)
 368 {
 369         struct sk_buff *skb;
 370         struct nfc_llcp_local *local;
 371         u16 size = 0;
 372
 373         pr_debug("Sending SYMM\n");
 374
 375         local = nfc_llcp_find_local(dev);
 376         if (local == NULL)
 377                 return -ENODEV;
 378
 379         size += LLCP_HEADER_SIZE;
 380         size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 381
 382         skb = alloc_skb(size, GFP_KERNEL);
 383         if (skb == NULL)
 384                 return -ENOMEM;
 385
 386         skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 387
 388         skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
 389
 390         __net_timestamp(skb);
 391
 392         nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_TX);
 393
 394         return nfc_data_exchange(dev, local->target_idx, skb,
 395                                  nfc_llcp_recv, local);
 396 }
 397
 398 int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 399 {
 400         struct nfc_llcp_local *local;
 401         struct sk_buff *skb;
 402         u8 *service_name_tlv = NULL, service_name_tlv_length;
 403         u8 *miux_tlv = NULL, miux_tlv_length;
 404         u8 *rw_tlv = NULL, rw_tlv_length, rw;
 405         int err;
 406         u16 size = 0, miux;
 407
 408         pr_debug("Sending CONNECT\n");
 409
 410         local = sock->local;
 411         if (local == NULL)
 412                 return -ENODEV;
 413
 414         if (sock->service_name != NULL) {
 415                 service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
 416                                                       sock->service_name,
 417                                                       sock->service_name_len,
 418                                                       &service_name_tlv_length);
 419                 size += service_name_tlv_length;
 420         }
 421
 422         /* If the socket parameters are not set, use the local ones */
 423         miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
 424                 local->miux : sock->miux;
 425         rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
 426
 427         miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
 428                                       &miux_tlv_length);
 429         size += miux_tlv_length;
 430
 431         rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
 432         size += rw_tlv_length;
 433
 434         pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
 435
 436         skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
 437         if (skb == NULL) {
 438                 err = -ENOMEM;
 439                 goto error_tlv;
 440         }
 441
 442         if (service_name_tlv != NULL)
 443                 skb = llcp_add_tlv(skb, service_name_tlv,
 444                                    service_name_tlv_length);
 445
 446         skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
 447         skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
 448
 449         skb_queue_tail(&local->tx_queue, skb);
 450
 451         return 0;
 452
 453 error_tlv:
 454         pr_err("error %d\n", err);
 455
 456         kfree(service_name_tlv);
 457         kfree(miux_tlv);
 458         kfree(rw_tlv);
 459
 460         return err;
 461 }
 462
 463 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 464 {
 465         struct nfc_llcp_local *local;
 466         struct sk_buff *skb;
 467         u8 *miux_tlv = NULL, miux_tlv_length;
 468         u8 *rw_tlv = NULL, rw_tlv_length, rw;
 469         int err;
 470         u16 size = 0, 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 = kzalloc(len, GFP_KERNEL);
 667         if (msg_data == NULL)
 668                 return -ENOMEM;
 669
 670         if (memcpy_fromiovec(msg_data, msg->msg_iov, 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                                 local->remote_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                         return -ENOMEM;
 691
 692                 skb_put(pdu, LLCP_SEQUENCE_SIZE);
 693
 694                 if (likely(frag_len > 0))
 695                         memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
 696
 697                 skb_queue_tail(&sock->tx_queue, pdu);
 698
 699                 lock_sock(sk);
 700
 701                 nfc_llcp_queue_i_frames(sock);
 702
 703                 release_sock(sk);
 704
 705                 remaining_len -= frag_len;
 706                 msg_ptr += frag_len;
 707         } while (remaining_len > 0);
 708
 709         kfree(msg_data);
 710
 711         return len;
 712 }
 713
 714 int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
 715                            struct msghdr *msg, size_t len)
 716 {
 717         struct sk_buff *pdu;
 718         struct nfc_llcp_local *local;
 719         size_t frag_len = 0, remaining_len;
 720         u8 *msg_ptr, *msg_data;
 721         u16 remote_miu;
 722         int err;
 723
 724         pr_debug("Send UI frame len %zd\n", len);
 725
 726         local = sock->local;
 727         if (local == NULL)
 728                 return -ENODEV;
 729
 730         msg_data = kzalloc(len, GFP_KERNEL);
 731         if (msg_data == NULL)
 732                 return -ENOMEM;
 733
 734         if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
 735                 kfree(msg_data);
 736                 return -EFAULT;
 737         }
 738
 739         remaining_len = len;
 740         msg_ptr = msg_data;
 741
 742         do {
 743                 remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
 744                                 local->remote_miu : sock->remote_miu;
 745
 746                 frag_len = min_t(size_t, remote_miu, remaining_len);
 747
 748                 pr_debug("Fragment %zd bytes remaining %zd",
 749                          frag_len, remaining_len);
 750
 751                 pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
 752                                          frag_len + LLCP_HEADER_SIZE, &err);
 753                 if (pdu == NULL) {
 754                         pr_err("Could not allocate PDU\n");
 755                         continue;
 756                 }
 757
 758                 pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
 759
 760                 if (likely(frag_len > 0))
 761                         memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
 762
 763                 /* No need to check for the peer RW for UI frames */
 764                 skb_queue_tail(&local->tx_queue, pdu);
 765
 766                 remaining_len -= frag_len;
 767                 msg_ptr += frag_len;
 768         } while (remaining_len > 0);
 769
 770         kfree(msg_data);
 771
 772         return len;
 773 }
 774
 775 int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
 776 {
 777         struct sk_buff *skb;
 778         struct nfc_llcp_local *local;
 779
 780         pr_debug("Send rr nr %d\n", sock->recv_n);
 781
 782         local = sock->local;
 783         if (local == NULL)
 784                 return -ENODEV;
 785
 786         skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
 787         if (skb == NULL)
 788                 return -ENOMEM;
 789
 790         skb_put(skb, LLCP_SEQUENCE_SIZE);
 791
 792         skb->data[2] = sock->recv_n;
 793
 794         skb_queue_head(&local->tx_queue, skb);
 795
 796         return 0;
 797 }