net/nfc/llcp/llcp.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/list.h>
  25 #include <linux/nfc.h>
  26
  27 #include "../nfc.h"
  28 #include "llcp.h"
  29
  30 static u8 llcp_magic[3] = {0x46, 0x66, 0x6d};
  31
  32 static struct list_head llcp_devices;
  33
  34 void nfc_llcp_sock_link(struct llcp_sock_list *l, struct sock *sk)
  35 {
  36         write_lock(&l->lock);
  37         sk_add_node(sk, &l->head);
  38         write_unlock(&l->lock);
  39 }
  40
  41 void nfc_llcp_sock_unlink(struct llcp_sock_list *l, struct sock *sk)
  42 {
  43         write_lock(&l->lock);
  44         sk_del_node_init(sk);
  45         write_unlock(&l->lock);
  46 }
  47
  48 static void nfc_llcp_socket_release(struct nfc_llcp_local *local, bool listen)
  49 {
  50         struct sock *sk;
  51         struct hlist_node *node, *tmp;
  52         struct nfc_llcp_sock *llcp_sock;
  53
  54         write_lock(&local->sockets.lock);
  55
  56         sk_for_each_safe(sk, node, tmp, &local->sockets.head) {
  57                 llcp_sock = nfc_llcp_sock(sk);
  58
  59                 lock_sock(sk);
  60
  61                 if (sk->sk_state == LLCP_CONNECTED)
  62                         nfc_put_device(llcp_sock->dev);
  63
  64                 if (sk->sk_state == LLCP_LISTEN) {
  65                         struct nfc_llcp_sock *lsk, *n;
  66                         struct sock *accept_sk;
  67
  68                         list_for_each_entry_safe(lsk, n, &llcp_sock->accept_queue,
  69                                                  accept_queue) {
  70                                 accept_sk = &lsk->sk;
  71                                 lock_sock(accept_sk);
  72
  73                                 nfc_llcp_accept_unlink(accept_sk);
  74
  75                                 accept_sk->sk_state = LLCP_CLOSED;
  76
  77                                 release_sock(accept_sk);
  78
  79                                 sock_orphan(accept_sk);
  80                         }
  81
  82                         if (listen == true) {
  83                                 release_sock(sk);
  84                                 continue;
  85                         }
  86                 }
  87
  88                 sk->sk_state = LLCP_CLOSED;
  89
  90                 release_sock(sk);
  91
  92                 sock_orphan(sk);
  93
  94                 sk_del_node_init(sk);
  95         }
  96
  97         write_unlock(&local->sockets.lock);
  98 }
  99
 100 struct nfc_llcp_local *nfc_llcp_local_get(struct nfc_llcp_local *local)
 101 {
 102         kref_get(&local->ref);
 103
 104         return local;
 105 }
 106
 107 static void local_release(struct kref *ref)
 108 {
 109         struct nfc_llcp_local *local;
 110
 111         local = container_of(ref, struct nfc_llcp_local, ref);
 112
 113         list_del(&local->list);
 114         nfc_llcp_socket_release(local, false);
 115         del_timer_sync(&local->link_timer);
 116         skb_queue_purge(&local->tx_queue);
 117         cancel_work_sync(&local->tx_work);
 118         cancel_work_sync(&local->rx_work);
 119         cancel_work_sync(&local->timeout_work);
 120         kfree_skb(local->rx_pending);
 121         kfree(local);
 122 }
 123
 124 int nfc_llcp_local_put(struct nfc_llcp_local *local)
 125 {
 126         if (local == NULL)
 127                 return 0;
 128
 129         return kref_put(&local->ref, local_release);
 130 }
 131
 132 static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
 133                                                u8 ssap, u8 dsap)
 134 {
 135         struct sock *sk;
 136         struct hlist_node *node;
 137         struct nfc_llcp_sock *llcp_sock;
 138
 139         pr_debug("ssap dsap %d %d\n", ssap, dsap);
 140
 141         if (ssap == 0 && dsap == 0)
 142                 return NULL;
 143
 144         read_lock(&local->sockets.lock);
 145
 146         llcp_sock = NULL;
 147
 148         sk_for_each(sk, node, &local->sockets.head) {
 149                 llcp_sock = nfc_llcp_sock(sk);
 150
 151                 if (llcp_sock->ssap == ssap && llcp_sock->dsap == dsap)
 152                         break;
 153         }
 154
 155         read_unlock(&local->sockets.lock);
 156
 157         if (llcp_sock == NULL)
 158                 return NULL;
 159
 160         sock_hold(&llcp_sock->sk);
 161
 162         return llcp_sock;
 163 }
 164
 165 static void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
 166 {
 167         sock_put(&sock->sk);
 168 }
 169
 170 static void nfc_llcp_timeout_work(struct work_struct *work)
 171 {
 172         struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
 173                                                     timeout_work);
 174
 175         nfc_dep_link_down(local->dev);
 176 }
 177
 178 static void nfc_llcp_symm_timer(unsigned long data)
 179 {
 180         struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
 181
 182         pr_err("SYMM timeout\n");
 183
 184         queue_work(system_nrt_wq, &local->timeout_work);
 185 }
 186
 187 struct nfc_llcp_local *nfc_llcp_find_local(struct nfc_dev *dev)
 188 {
 189         struct nfc_llcp_local *local, *n;
 190
 191         list_for_each_entry_safe(local, n, &llcp_devices, list)
 192                 if (local->dev == dev)
 193                         return local;
 194
 195         pr_debug("No device found\n");
 196
 197         return NULL;
 198 }
 199
 200 static char *wks[] = {
 201         NULL,
 202         NULL, /* SDP */
 203         "urn:nfc:sn:ip",
 204         "urn:nfc:sn:obex",
 205         "urn:nfc:sn:snep",
 206 };
 207
 208 static int nfc_llcp_wks_sap(char *service_name, size_t service_name_len)
 209 {
 210         int sap, num_wks;
 211
 212         pr_debug("%s\n", service_name);
 213
 214         if (service_name == NULL)
 215                 return -EINVAL;
 216
 217         num_wks = ARRAY_SIZE(wks);
 218
 219         for (sap = 0; sap < num_wks; sap++) {
 220                 if (wks[sap] == NULL)
 221                         continue;
 222
 223                 if (strncmp(wks[sap], service_name, service_name_len) == 0)
 224                         return sap;
 225         }
 226
 227         return -EINVAL;
 228 }
 229
 230 static
 231 struct nfc_llcp_sock *nfc_llcp_sock_from_sn(struct nfc_llcp_local *local,
 232                                             u8 *sn, size_t sn_len)
 233 {
 234         struct sock *sk;
 235         struct hlist_node *node;
 236         struct nfc_llcp_sock *llcp_sock, *tmp_sock;
 237
 238         pr_debug("sn %zd %p\n", sn_len, sn);
 239
 240         if (sn == NULL || sn_len == 0)
 241                 return NULL;
 242
 243         read_lock(&local->sockets.lock);
 244
 245         llcp_sock = NULL;
 246
 247         sk_for_each(sk, node, &local->sockets.head) {
 248                 tmp_sock = nfc_llcp_sock(sk);
 249
 250                 pr_debug("llcp sock %p\n", tmp_sock);
 251
 252                 if (tmp_sock->sk.sk_state != LLCP_LISTEN)
 253                         continue;
 254
 255                 if (tmp_sock->service_name == NULL ||
 256                     tmp_sock->service_name_len == 0)
 257                         continue;
 258
 259                 if (tmp_sock->service_name_len != sn_len)
 260                         continue;
 261
 262                 if (memcmp(sn, tmp_sock->service_name, sn_len) == 0) {
 263                         llcp_sock = tmp_sock;
 264                         break;
 265                 }
 266         }
 267
 268         read_unlock(&local->sockets.lock);
 269
 270         pr_debug("Found llcp sock %p\n", llcp_sock);
 271
 272         return llcp_sock;
 273 }
 274
 275 u8 nfc_llcp_get_sdp_ssap(struct nfc_llcp_local *local,
 276                          struct nfc_llcp_sock *sock)
 277 {
 278         mutex_lock(&local->sdp_lock);
 279
 280         if (sock->service_name != NULL && sock->service_name_len > 0) {
 281                 int ssap = nfc_llcp_wks_sap(sock->service_name,
 282                                             sock->service_name_len);
 283
 284                 if (ssap > 0) {
 285                         pr_debug("WKS %d\n", ssap);
 286
 287                         /* This is a WKS, let's check if it's free */
 288                         if (local->local_wks & BIT(ssap)) {
 289                                 mutex_unlock(&local->sdp_lock);
 290
 291                                 return LLCP_SAP_MAX;
 292                         }
 293
 294                         set_bit(ssap, &local->local_wks);
 295                         mutex_unlock(&local->sdp_lock);
 296
 297                         return ssap;
 298                 }
 299
 300                 /*
 301                  * Check if there already is a non WKS socket bound
 302                  * to this service name.
 303                  */
 304                 if (nfc_llcp_sock_from_sn(local, sock->service_name,
 305                                           sock->service_name_len) != NULL) {
 306                         mutex_unlock(&local->sdp_lock);
 307
 308                         return LLCP_SAP_MAX;
 309                 }
 310
 311                 mutex_unlock(&local->sdp_lock);
 312
 313                 return LLCP_SDP_UNBOUND;
 314
 315         } else if (sock->ssap != 0 && sock->ssap < LLCP_WKS_NUM_SAP) {
 316                 if (!test_bit(sock->ssap, &local->local_wks)) {
 317                         set_bit(sock->ssap, &local->local_wks);
 318                         mutex_unlock(&local->sdp_lock);
 319
 320                         return sock->ssap;
 321                 }
 322         }
 323
 324         mutex_unlock(&local->sdp_lock);
 325
 326         return LLCP_SAP_MAX;
 327 }
 328
 329 u8 nfc_llcp_get_local_ssap(struct nfc_llcp_local *local)
 330 {
 331         u8 local_ssap;
 332
 333         mutex_lock(&local->sdp_lock);
 334
 335         local_ssap = find_first_zero_bit(&local->local_sap, LLCP_LOCAL_NUM_SAP);
 336         if (local_ssap == LLCP_LOCAL_NUM_SAP) {
 337                 mutex_unlock(&local->sdp_lock);
 338                 return LLCP_SAP_MAX;
 339         }
 340
 341         set_bit(local_ssap, &local->local_sap);
 342
 343         mutex_unlock(&local->sdp_lock);
 344
 345         return local_ssap + LLCP_LOCAL_SAP_OFFSET;
 346 }
 347
 348 void nfc_llcp_put_ssap(struct nfc_llcp_local *local, u8 ssap)
 349 {
 350         u8 local_ssap;
 351         unsigned long *sdp;
 352
 353         if (ssap < LLCP_WKS_NUM_SAP) {
 354                 local_ssap = ssap;
 355                 sdp = &local->local_wks;
 356         } else if (ssap < LLCP_LOCAL_NUM_SAP) {
 357                 atomic_t *client_cnt;
 358
 359                 local_ssap = ssap - LLCP_WKS_NUM_SAP;
 360                 sdp = &local->local_sdp;
 361                 client_cnt = &local->local_sdp_cnt[local_ssap];
 362
 363                 pr_debug("%d clients\n", atomic_read(client_cnt));
 364
 365                 mutex_lock(&local->sdp_lock);
 366
 367                 if (atomic_dec_and_test(client_cnt)) {
 368                         struct nfc_llcp_sock *l_sock;
 369
 370                         pr_debug("No more clients for SAP %d\n", ssap);
 371
 372                         clear_bit(local_ssap, sdp);
 373
 374                         /* Find the listening sock and set it back to UNBOUND */
 375                         l_sock = nfc_llcp_sock_get(local, ssap, LLCP_SAP_SDP);
 376                         if (l_sock) {
 377                                 l_sock->ssap = LLCP_SDP_UNBOUND;
 378                                 nfc_llcp_sock_put(l_sock);
 379                         }
 380                 }
 381
 382                 mutex_unlock(&local->sdp_lock);
 383
 384                 return;
 385         } else if (ssap < LLCP_MAX_SAP) {
 386                 local_ssap = ssap - LLCP_LOCAL_NUM_SAP;
 387                 sdp = &local->local_sap;
 388         } else {
 389                 return;
 390         }
 391
 392         mutex_lock(&local->sdp_lock);
 393
 394         clear_bit(local_ssap, sdp);
 395
 396         mutex_unlock(&local->sdp_lock);
 397 }
 398
 399 static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
 400 {
 401         u8 ssap;
 402
 403         mutex_lock(&local->sdp_lock);
 404
 405         ssap = find_first_zero_bit(&local->local_sdp, LLCP_SDP_NUM_SAP);
 406         if (ssap == LLCP_SDP_NUM_SAP) {
 407                 mutex_unlock(&local->sdp_lock);
 408
 409                 return LLCP_SAP_MAX;
 410         }
 411
 412         pr_debug("SDP ssap %d\n", LLCP_WKS_NUM_SAP + ssap);
 413
 414         set_bit(ssap, &local->local_sdp);
 415
 416         mutex_unlock(&local->sdp_lock);
 417
 418         return LLCP_WKS_NUM_SAP + ssap;
 419 }
 420
 421 static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 422 {
 423         u8 *gb_cur, *version_tlv, version, version_length;
 424         u8 *lto_tlv, lto, lto_length;
 425         u8 *wks_tlv, wks_length;
 426         u8 *miux_tlv, miux_length;
 427         __be16 miux;
 428         u8 gb_len = 0;
 429         int ret = 0;
 430
 431         version = LLCP_VERSION_11;
 432         version_tlv = nfc_llcp_build_tlv(LLCP_TLV_VERSION, &version,
 433                                          1, &version_length);
 434         gb_len += version_length;
 435
 436         /* 1500 ms */
 437         lto = 150;
 438         lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &lto, 1, &lto_length);
 439         gb_len += lto_length;
 440
 441         pr_debug("Local wks 0x%lx\n", local->local_wks);
 442         wks_tlv = nfc_llcp_build_tlv(LLCP_TLV_WKS, (u8 *)&local->local_wks, 2,
 443                                      &wks_length);
 444         gb_len += wks_length;
 445
 446         miux = cpu_to_be16(LLCP_MAX_MIUX);
 447         miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
 448                                       &miux_length);
 449         gb_len += miux_length;
 450
 451         gb_len += ARRAY_SIZE(llcp_magic);
 452
 453         if (gb_len > NFC_MAX_GT_LEN) {
 454                 ret = -EINVAL;
 455                 goto out;
 456         }
 457
 458         gb_cur = local->gb;
 459
 460         memcpy(gb_cur, llcp_magic, ARRAY_SIZE(llcp_magic));
 461         gb_cur += ARRAY_SIZE(llcp_magic);
 462
 463         memcpy(gb_cur, version_tlv, version_length);
 464         gb_cur += version_length;
 465
 466         memcpy(gb_cur, lto_tlv, lto_length);
 467         gb_cur += lto_length;
 468
 469         memcpy(gb_cur, wks_tlv, wks_length);
 470         gb_cur += wks_length;
 471
 472         memcpy(gb_cur, miux_tlv, miux_length);
 473         gb_cur += miux_length;
 474
 475         local->gb_len = gb_len;
 476
 477 out:
 478         kfree(version_tlv);
 479         kfree(lto_tlv);
 480         kfree(wks_tlv);
 481         kfree(miux_tlv);
 482
 483         return ret;
 484 }
 485
 486 u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len)
 487 {
 488         struct nfc_llcp_local *local;
 489
 490         local = nfc_llcp_find_local(dev);
 491         if (local == NULL) {
 492                 *general_bytes_len = 0;
 493                 return NULL;
 494         }
 495
 496         nfc_llcp_build_gb(local);
 497
 498         *general_bytes_len = local->gb_len;
 499
 500         return local->gb;
 501 }
 502
 503 int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len)
 504 {
 505         struct nfc_llcp_local *local = nfc_llcp_find_local(dev);
 506
 507         if (local == NULL) {
 508                 pr_err("No LLCP device\n");
 509                 return -ENODEV;
 510         }
 511
 512         memset(local->remote_gb, 0, NFC_MAX_GT_LEN);
 513         memcpy(local->remote_gb, gb, gb_len);
 514         local->remote_gb_len = gb_len;
 515
 516         if (local->remote_gb == NULL || local->remote_gb_len == 0)
 517                 return -ENODEV;
 518
 519         if (memcmp(local->remote_gb, llcp_magic, 3)) {
 520                 pr_err("MAC does not support LLCP\n");
 521                 return -EINVAL;
 522         }
 523
 524         return nfc_llcp_parse_gb_tlv(local,
 525                                      &local->remote_gb[3],
 526                                      local->remote_gb_len - 3);
 527 }
 528
 529 static u8 nfc_llcp_dsap(struct sk_buff *pdu)
 530 {
 531         return (pdu->data[0] & 0xfc) >> 2;
 532 }
 533
 534 static u8 nfc_llcp_ptype(struct sk_buff *pdu)
 535 {
 536         return ((pdu->data[0] & 0x03) << 2) | ((pdu->data[1] & 0xc0) >> 6);
 537 }
 538
 539 static u8 nfc_llcp_ssap(struct sk_buff *pdu)
 540 {
 541         return pdu->data[1] & 0x3f;
 542 }
 543
 544 static u8 nfc_llcp_ns(struct sk_buff *pdu)
 545 {
 546         return pdu->data[2] >> 4;
 547 }
 548
 549 static u8 nfc_llcp_nr(struct sk_buff *pdu)
 550 {
 551         return pdu->data[2] & 0xf;
 552 }
 553
 554 static void nfc_llcp_set_nrns(struct nfc_llcp_sock *sock, struct sk_buff *pdu)
 555 {
 556         pdu->data[2] = (sock->send_n << 4) | (sock->recv_n);
 557         sock->send_n = (sock->send_n + 1) % 16;
 558         sock->recv_ack_n = (sock->recv_n - 1) % 16;
 559 }
 560
 561 static void nfc_llcp_tx_work(struct work_struct *work)
 562 {
 563         struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
 564                                                     tx_work);
 565         struct sk_buff *skb;
 566         struct sock *sk;
 567         struct nfc_llcp_sock *llcp_sock;
 568
 569         skb = skb_dequeue(&local->tx_queue);
 570         if (skb != NULL) {
 571                 sk = skb->sk;
 572                 llcp_sock = nfc_llcp_sock(sk);
 573                 if (llcp_sock != NULL) {
 574                         int ret;
 575
 576                         pr_debug("Sending pending skb\n");
 577                         print_hex_dump(KERN_DEBUG, "LLCP Tx: ",
 578                                        DUMP_PREFIX_OFFSET, 16, 1,
 579                                        skb->data, skb->len, true);
 580
 581                         ret = nfc_data_exchange(local->dev, local->target_idx,
 582                                                 skb, nfc_llcp_recv, local);
 583
 584                         if (!ret && nfc_llcp_ptype(skb) == LLCP_PDU_I) {
 585                                 skb = skb_get(skb);
 586                                 skb_queue_tail(&llcp_sock->tx_pending_queue,
 587                                                skb);
 588                         }
 589                 } else {
 590                         nfc_llcp_send_symm(local->dev);
 591                 }
 592         } else {
 593                 nfc_llcp_send_symm(local->dev);
 594         }
 595
 596         mod_timer(&local->link_timer,
 597                   jiffies + msecs_to_jiffies(2 * local->remote_lto));
 598 }
 599
 600 static struct nfc_llcp_sock *nfc_llcp_connecting_sock_get(struct nfc_llcp_local *local,
 601                                                           u8 ssap)
 602 {
 603         struct sock *sk;
 604         struct nfc_llcp_sock *llcp_sock;
 605         struct hlist_node *node;
 606
 607         read_lock(&local->connecting_sockets.lock);
 608
 609         sk_for_each(sk, node, &local->connecting_sockets.head) {
 610                 llcp_sock = nfc_llcp_sock(sk);
 611
 612                 if (llcp_sock->ssap == ssap) {
 613                         sock_hold(&llcp_sock->sk);
 614                         goto out;
 615                 }
 616         }
 617
 618         llcp_sock = NULL;
 619
 620 out:
 621         read_unlock(&local->connecting_sockets.lock);
 622
 623         return llcp_sock;
 624 }
 625
 626 static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
 627                                                   u8 *sn, size_t sn_len)
 628 {
 629         struct nfc_llcp_sock *llcp_sock;
 630
 631         llcp_sock = nfc_llcp_sock_from_sn(local, sn, sn_len);
 632
 633         if (llcp_sock == NULL)
 634                 return NULL;
 635
 636         sock_hold(&llcp_sock->sk);
 637
 638         return llcp_sock;
 639 }
 640
 641 static u8 *nfc_llcp_connect_sn(struct sk_buff *skb, size_t *sn_len)
 642 {
 643         u8 *tlv = &skb->data[2], type, length;
 644         size_t tlv_array_len = skb->len - LLCP_HEADER_SIZE, offset = 0;
 645
 646         while (offset < tlv_array_len) {
 647                 type = tlv[0];
 648                 length = tlv[1];
 649
 650                 pr_debug("type 0x%x length %d\n", type, length);
 651
 652                 if (type == LLCP_TLV_SN) {
 653                         *sn_len = length;
 654                         return &tlv[2];
 655                 }
 656
 657                 offset += length + 2;
 658                 tlv += length + 2;
 659         }
 660
 661         return NULL;
 662 }
 663
 664 static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
 665                                   struct sk_buff *skb)
 666 {
 667         struct sock *new_sk, *parent;
 668         struct nfc_llcp_sock *sock, *new_sock;
 669         u8 dsap, ssap, reason;
 670
 671         dsap = nfc_llcp_dsap(skb);
 672         ssap = nfc_llcp_ssap(skb);
 673
 674         pr_debug("%d %d\n", dsap, ssap);
 675
 676         if (dsap != LLCP_SAP_SDP) {
 677                 sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
 678                 if (sock == NULL || sock->sk.sk_state != LLCP_LISTEN) {
 679                         reason = LLCP_DM_NOBOUND;
 680                         goto fail;
 681                 }
 682         } else {
 683                 u8 *sn;
 684                 size_t sn_len;
 685
 686                 sn = nfc_llcp_connect_sn(skb, &sn_len);
 687                 if (sn == NULL) {
 688                         reason = LLCP_DM_NOBOUND;
 689                         goto fail;
 690                 }
 691
 692                 pr_debug("Service name length %zu\n", sn_len);
 693
 694                 sock = nfc_llcp_sock_get_sn(local, sn, sn_len);
 695                 if (sock == NULL) {
 696                         reason = LLCP_DM_NOBOUND;
 697                         goto fail;
 698                 }
 699         }
 700
 701         lock_sock(&sock->sk);
 702
 703         parent = &sock->sk;
 704
 705         if (sk_acceptq_is_full(parent)) {
 706                 reason = LLCP_DM_REJ;
 707                 release_sock(&sock->sk);
 708                 sock_put(&sock->sk);
 709                 goto fail;
 710         }
 711
 712         if (sock->ssap == LLCP_SDP_UNBOUND) {
 713                 u8 ssap = nfc_llcp_reserve_sdp_ssap(local);
 714
 715                 pr_debug("First client, reserving %d\n", ssap);
 716
 717                 if (ssap == LLCP_SAP_MAX) {
 718                         reason = LLCP_DM_REJ;
 719                         release_sock(&sock->sk);
 720                         sock_put(&sock->sk);
 721                         goto fail;
 722                 }
 723
 724                 sock->ssap = ssap;
 725         }
 726
 727         new_sk = nfc_llcp_sock_alloc(NULL, parent->sk_type, GFP_ATOMIC);
 728         if (new_sk == NULL) {
 729                 reason = LLCP_DM_REJ;
 730                 release_sock(&sock->sk);
 731                 sock_put(&sock->sk);
 732                 goto fail;
 733         }
 734
 735         new_sock = nfc_llcp_sock(new_sk);
 736         new_sock->dev = local->dev;
 737         new_sock->local = nfc_llcp_local_get(local);
 738         new_sock->miu = local->remote_miu;
 739         new_sock->nfc_protocol = sock->nfc_protocol;
 740         new_sock->dsap = ssap;
 741         new_sock->target_idx = local->target_idx;
 742         new_sock->parent = parent;
 743         new_sock->ssap = sock->ssap;
 744         if (sock->ssap < LLCP_LOCAL_NUM_SAP && sock->ssap >= LLCP_WKS_NUM_SAP) {
 745                 atomic_t *client_count;
 746
 747                 pr_debug("reserved_ssap %d for %p\n", sock->ssap, new_sock);
 748
 749                 client_count =
 750                         &local->local_sdp_cnt[sock->ssap - LLCP_WKS_NUM_SAP];
 751
 752                 atomic_inc(client_count);
 753                 new_sock->reserved_ssap = sock->ssap;
 754         }
 755
 756         nfc_llcp_parse_connection_tlv(new_sock, &skb->data[LLCP_HEADER_SIZE],
 757                                       skb->len - LLCP_HEADER_SIZE);
 758
 759         pr_debug("new sock %p sk %p\n", new_sock, &new_sock->sk);
 760
 761         nfc_llcp_sock_link(&local->sockets, new_sk);
 762
 763         nfc_llcp_accept_enqueue(&sock->sk, new_sk);
 764
 765         nfc_get_device(local->dev->idx);
 766
 767         new_sk->sk_state = LLCP_CONNECTED;
 768
 769         /* Wake the listening processes */
 770         parent->sk_data_ready(parent, 0);
 771
 772         /* Send CC */
 773         nfc_llcp_send_cc(new_sock);
 774
 775         release_sock(&sock->sk);
 776         sock_put(&sock->sk);
 777
 778         return;
 779
 780 fail:
 781         /* Send DM */
 782         nfc_llcp_send_dm(local, dsap, ssap, reason);
 783
 784         return;
 785
 786 }
 787
 788 int nfc_llcp_queue_i_frames(struct nfc_llcp_sock *sock)
 789 {
 790         int nr_frames = 0;
 791         struct nfc_llcp_local *local = sock->local;
 792
 793         pr_debug("Remote ready %d tx queue len %d remote rw %d",
 794                  sock->remote_ready, skb_queue_len(&sock->tx_pending_queue),
 795                  sock->rw);
 796
 797         /* Try to queue some I frames for transmission */
 798         while (sock->remote_ready &&
 799                skb_queue_len(&sock->tx_pending_queue) < sock->rw) {
 800                 struct sk_buff *pdu;
 801
 802                 pdu = skb_dequeue(&sock->tx_queue);
 803                 if (pdu == NULL)
 804                         break;
 805
 806                 /* Update N(S)/N(R) */
 807                 nfc_llcp_set_nrns(sock, pdu);
 808
 809                 skb_queue_tail(&local->tx_queue, pdu);
 810                 nr_frames++;
 811         }
 812
 813         return nr_frames;
 814 }
 815
 816 static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local,
 817                                struct sk_buff *skb)
 818 {
 819         struct nfc_llcp_sock *llcp_sock;
 820         struct sock *sk;
 821         u8 dsap, ssap, ptype, ns, nr;
 822
 823         ptype = nfc_llcp_ptype(skb);
 824         dsap = nfc_llcp_dsap(skb);
 825         ssap = nfc_llcp_ssap(skb);
 826         ns = nfc_llcp_ns(skb);
 827         nr = nfc_llcp_nr(skb);
 828
 829         pr_debug("%d %d R %d S %d\n", dsap, ssap, nr, ns);
 830
 831         llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
 832         if (llcp_sock == NULL) {
 833                 nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
 834                 return;
 835         }
 836
 837         sk = &llcp_sock->sk;
 838         lock_sock(sk);
 839         if (sk->sk_state == LLCP_CLOSED) {
 840                 release_sock(sk);
 841                 nfc_llcp_sock_put(llcp_sock);
 842         }
 843
 844         /* Pass the payload upstream */
 845         if (ptype == LLCP_PDU_I) {
 846                 pr_debug("I frame, queueing on %p\n", &llcp_sock->sk);
 847
 848                 if (ns == llcp_sock->recv_n)
 849                         llcp_sock->recv_n = (llcp_sock->recv_n + 1) % 16;
 850                 else
 851                         pr_err("Received out of sequence I PDU\n");
 852
 853                 skb_pull(skb, LLCP_HEADER_SIZE + LLCP_SEQUENCE_SIZE);
 854                 if (sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
 855                         pr_err("receive queue is full\n");
 856                         skb_queue_head(&llcp_sock->tx_backlog_queue, skb);
 857                 }
 858         }
 859
 860         /* Remove skbs from the pending queue */
 861         if (llcp_sock->send_ack_n != nr) {
 862                 struct sk_buff *s, *tmp;
 863
 864                 llcp_sock->send_ack_n = nr;
 865
 866                 /* Remove and free all skbs until ns == nr */
 867                 skb_queue_walk_safe(&llcp_sock->tx_pending_queue, s, tmp) {
 868                         skb_unlink(s, &llcp_sock->tx_pending_queue);
 869                         kfree_skb(s);
 870
 871                         if (nfc_llcp_ns(s) == nr)
 872                                 break;
 873                 }
 874
 875                 /* Re-queue the remaining skbs for transmission */
 876                 skb_queue_reverse_walk_safe(&llcp_sock->tx_pending_queue,
 877                                             s, tmp) {
 878                         skb_unlink(s, &llcp_sock->tx_pending_queue);
 879                         skb_queue_head(&local->tx_queue, s);
 880                 }
 881         }
 882
 883         if (ptype == LLCP_PDU_RR)
 884                 llcp_sock->remote_ready = true;
 885         else if (ptype == LLCP_PDU_RNR)
 886                 llcp_sock->remote_ready = false;
 887
 888         if (nfc_llcp_queue_i_frames(llcp_sock) == 0 && ptype == LLCP_PDU_I)
 889                 nfc_llcp_send_rr(llcp_sock);
 890
 891         release_sock(sk);
 892         nfc_llcp_sock_put(llcp_sock);
 893 }
 894
 895 static void nfc_llcp_recv_disc(struct nfc_llcp_local *local,
 896                                struct sk_buff *skb)
 897 {
 898         struct nfc_llcp_sock *llcp_sock;
 899         struct sock *sk;
 900         u8 dsap, ssap;
 901
 902         dsap = nfc_llcp_dsap(skb);
 903         ssap = nfc_llcp_ssap(skb);
 904
 905         llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
 906         if (llcp_sock == NULL) {
 907                 nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
 908                 return;
 909         }
 910
 911         sk = &llcp_sock->sk;
 912         lock_sock(sk);
 913         if (sk->sk_state == LLCP_CLOSED) {
 914                 release_sock(sk);
 915                 nfc_llcp_sock_put(llcp_sock);
 916         }
 917
 918         if (sk->sk_state == LLCP_CONNECTED) {
 919                 nfc_put_device(local->dev);
 920                 sk->sk_state = LLCP_CLOSED;
 921                 sk->sk_state_change(sk);
 922         }
 923
 924         nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_DISC);
 925
 926         release_sock(sk);
 927         nfc_llcp_sock_put(llcp_sock);
 928 }
 929
 930 static void nfc_llcp_recv_cc(struct nfc_llcp_local *local, struct sk_buff *skb)
 931 {
 932         struct nfc_llcp_sock *llcp_sock;
 933         struct sock *sk;
 934         u8 dsap, ssap;
 935
 936         dsap = nfc_llcp_dsap(skb);
 937         ssap = nfc_llcp_ssap(skb);
 938
 939         llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
 940         if (llcp_sock == NULL) {
 941                 pr_err("Invalid CC\n");
 942                 nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
 943
 944                 return;
 945         }
 946
 947         sk = &llcp_sock->sk;
 948
 949         /* Unlink from connecting and link to the client array */
 950         nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
 951         nfc_llcp_sock_link(&local->sockets, sk);
 952         llcp_sock->dsap = ssap;
 953
 954         nfc_llcp_parse_connection_tlv(llcp_sock, &skb->data[LLCP_HEADER_SIZE],
 955                                       skb->len - LLCP_HEADER_SIZE);
 956
 957         sk->sk_state = LLCP_CONNECTED;
 958         sk->sk_state_change(sk);
 959
 960         nfc_llcp_sock_put(llcp_sock);
 961 }
 962
 963 static void nfc_llcp_recv_dm(struct nfc_llcp_local *local, struct sk_buff *skb)
 964 {
 965         struct nfc_llcp_sock *llcp_sock;
 966         struct sock *sk;
 967         u8 dsap, ssap, reason;
 968
 969         dsap = nfc_llcp_dsap(skb);
 970         ssap = nfc_llcp_ssap(skb);
 971         reason = skb->data[2];
 972
 973         pr_debug("%d %d reason %d\n", ssap, dsap, reason);
 974
 975         switch (reason) {
 976         case LLCP_DM_NOBOUND:
 977         case LLCP_DM_REJ:
 978                 llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
 979                 break;
 980
 981         default:
 982                 llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
 983                 break;
 984         }
 985
 986         if (llcp_sock == NULL) {
 987                 pr_err("Invalid DM\n");
 988                 return;
 989         }
 990
 991         sk = &llcp_sock->sk;
 992
 993         sk->sk_err = ENXIO;
 994         sk->sk_state = LLCP_CLOSED;
 995         sk->sk_state_change(sk);
 996
 997         nfc_llcp_sock_put(llcp_sock);
 998
 999         return;
1000 }
1001
1002 static void nfc_llcp_rx_work(struct work_struct *work)
1003 {
1004         struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
1005                                                     rx_work);
1006         u8 dsap, ssap, ptype;
1007         struct sk_buff *skb;
1008
1009         skb = local->rx_pending;
1010         if (skb == NULL) {
1011                 pr_debug("No pending SKB\n");
1012                 return;
1013         }
1014
1015         ptype = nfc_llcp_ptype(skb);
1016         dsap = nfc_llcp_dsap(skb);
1017         ssap = nfc_llcp_ssap(skb);
1018
1019         pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
1020
1021         if (ptype != LLCP_PDU_SYMM)
1022                 print_hex_dump(KERN_DEBUG, "LLCP Rx: ", DUMP_PREFIX_OFFSET,
1023                                16, 1, skb->data, skb->len, true);
1024
1025         switch (ptype) {
1026         case LLCP_PDU_SYMM:
1027                 pr_debug("SYMM\n");
1028                 break;
1029
1030         case LLCP_PDU_CONNECT:
1031                 pr_debug("CONNECT\n");
1032                 nfc_llcp_recv_connect(local, skb);
1033                 break;
1034
1035         case LLCP_PDU_DISC:
1036                 pr_debug("DISC\n");
1037                 nfc_llcp_recv_disc(local, skb);
1038                 break;
1039
1040         case LLCP_PDU_CC:
1041                 pr_debug("CC\n");
1042                 nfc_llcp_recv_cc(local, skb);
1043                 break;
1044
1045         case LLCP_PDU_DM:
1046                 pr_debug("DM\n");
1047                 nfc_llcp_recv_dm(local, skb);
1048                 break;
1049
1050         case LLCP_PDU_I:
1051         case LLCP_PDU_RR:
1052         case LLCP_PDU_RNR:
1053                 pr_debug("I frame\n");
1054                 nfc_llcp_recv_hdlc(local, skb);
1055                 break;
1056
1057         }
1058
1059         queue_work(system_nrt_wq, &local->tx_work);
1060         kfree_skb(local->rx_pending);
1061         local->rx_pending = NULL;
1062
1063         return;
1064 }
1065
1066 void nfc_llcp_recv(void *data, struct sk_buff *skb, int err)
1067 {
1068         struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
1069
1070         pr_debug("Received an LLCP PDU\n");
1071         if (err < 0) {
1072                 pr_err("err %d\n", err);
1073                 return;
1074         }
1075
1076         local->rx_pending = skb_get(skb);
1077         del_timer(&local->link_timer);
1078         queue_work(system_nrt_wq, &local->rx_work);
1079
1080         return;
1081 }
1082
1083 int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb)
1084 {
1085         struct nfc_llcp_local *local;
1086
1087         local = nfc_llcp_find_local(dev);
1088         if (local == NULL)
1089                 return -ENODEV;
1090
1091         local->rx_pending = skb_get(skb);
1092         del_timer(&local->link_timer);
1093         queue_work(system_nrt_wq, &local->rx_work);
1094
1095         return 0;
1096 }
1097
1098 void nfc_llcp_mac_is_down(struct nfc_dev *dev)
1099 {
1100         struct nfc_llcp_local *local;
1101
1102         local = nfc_llcp_find_local(dev);
1103         if (local == NULL)
1104                 return;
1105
1106         /* Close and purge all existing sockets */
1107         nfc_llcp_socket_release(local, true);
1108 }
1109
1110 void nfc_llcp_mac_is_up(struct nfc_dev *dev, u32 target_idx,
1111                         u8 comm_mode, u8 rf_mode)
1112 {
1113         struct nfc_llcp_local *local;
1114
1115         pr_debug("rf mode %d\n", rf_mode);
1116
1117         local = nfc_llcp_find_local(dev);
1118         if (local == NULL)
1119                 return;
1120
1121         local->target_idx = target_idx;
1122         local->comm_mode = comm_mode;
1123         local->rf_mode = rf_mode;
1124
1125         if (rf_mode == NFC_RF_INITIATOR) {
1126                 pr_debug("Queueing Tx work\n");
1127
1128                 queue_work(system_nrt_wq, &local->tx_work);
1129         } else {
1130                 mod_timer(&local->link_timer,
1131                           jiffies + msecs_to_jiffies(local->remote_lto));
1132         }
1133 }
1134
1135 int nfc_llcp_register_device(struct nfc_dev *ndev)
1136 {
1137         struct nfc_llcp_local *local;
1138
1139         local = kzalloc(sizeof(struct nfc_llcp_local), GFP_KERNEL);
1140         if (local == NULL)
1141                 return -ENOMEM;
1142
1143         local->dev = ndev;
1144         INIT_LIST_HEAD(&local->list);
1145         kref_init(&local->ref);
1146         mutex_init(&local->sdp_lock);
1147         init_timer(&local->link_timer);
1148         local->link_timer.data = (unsigned long) local;
1149         local->link_timer.function = nfc_llcp_symm_timer;
1150
1151         skb_queue_head_init(&local->tx_queue);
1152         INIT_WORK(&local->tx_work, nfc_llcp_tx_work);
1153
1154         local->rx_pending = NULL;
1155         INIT_WORK(&local->rx_work, nfc_llcp_rx_work);
1156
1157         INIT_WORK(&local->timeout_work, nfc_llcp_timeout_work);
1158
1159         rwlock_init(&local->sockets.lock);
1160         rwlock_init(&local->connecting_sockets.lock);
1161
1162         nfc_llcp_build_gb(local);
1163
1164         local->remote_miu = LLCP_DEFAULT_MIU;
1165         local->remote_lto = LLCP_DEFAULT_LTO;
1166
1167         list_add(&llcp_devices, &local->list);
1168
1169         return 0;
1170 }
1171
1172 void nfc_llcp_unregister_device(struct nfc_dev *dev)
1173 {
1174         struct nfc_llcp_local *local = nfc_llcp_find_local(dev);
1175
1176         if (local == NULL) {
1177                 pr_debug("No such device\n");
1178                 return;
1179         }
1180
1181         nfc_llcp_local_put(local);
1182 }
1183
1184 int __init nfc_llcp_init(void)
1185 {
1186         INIT_LIST_HEAD(&llcp_devices);
1187
1188         return nfc_llcp_sock_init();
1189 }
1190
1191 void nfc_llcp_exit(void)
1192 {
1193         nfc_llcp_sock_exit();
1194 }