net/bluetooth/l2cap_core.c

   1 /*
   2    BlueZ - Bluetooth protocol stack for Linux
   3    Copyright (C) 2000-2001 Qualcomm Incorporated
   4    Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
   5    Copyright (C) 2010 Google Inc.
   6    Copyright (C) 2011 ProFUSION Embedded Systems
   7    Copyright (c) 2012 Code Aurora Forum.  All rights reserved.
   8
   9    Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License version 2 as
  13    published by the Free Software Foundation;
  14
  15    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  16    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
  18    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
  19    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
  20    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  21    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  22    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  23
  24    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
  25    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
  26    SOFTWARE IS DISCLAIMED.
  27 */
  28
  29 /* Bluetooth L2CAP core. */
  30
  31 #include <linux/module.h>
  32
  33 #include <linux/debugfs.h>
  34 #include <linux/crc16.h>
  35
  36 #include <net/bluetooth/bluetooth.h>
  37 #include <net/bluetooth/hci_core.h>
  38 #include <net/bluetooth/l2cap.h>
  39 #include <net/bluetooth/smp.h>
  40 #include <net/bluetooth/a2mp.h>
  41 #include <net/bluetooth/amp.h>
  42
  43 bool disable_ertm;
  44
  45 static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN;
  46 static u8 l2cap_fixed_chan[8] = { L2CAP_FC_L2CAP, };
  47
  48 static LIST_HEAD(chan_list);
  49 static DEFINE_RWLOCK(chan_list_lock);
  50
  51 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
  52                                        u8 code, u8 ident, u16 dlen, void *data);
  53 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
  54                            void *data);
  55 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
  56 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
  57
  58 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
  59                      struct sk_buff_head *skbs, u8 event);
  60
  61 /* ---- L2CAP channels ---- */
  62
  63 static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
  64                                                    u16 cid)
  65 {
  66         struct l2cap_chan *c;
  67
  68         list_for_each_entry(c, &conn->chan_l, list) {
  69                 if (c->dcid == cid)
  70                         return c;
  71         }
  72         return NULL;
  73 }
  74
  75 static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
  76                                                    u16 cid)
  77 {
  78         struct l2cap_chan *c;
  79
  80         list_for_each_entry(c, &conn->chan_l, list) {
  81                 if (c->scid == cid)
  82                         return c;
  83         }
  84         return NULL;
  85 }
  86
  87 /* Find channel with given SCID.
  88  * Returns locked channel. */
  89 static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
  90                                                  u16 cid)
  91 {
  92         struct l2cap_chan *c;
  93
  94         mutex_lock(&conn->chan_lock);
  95         c = __l2cap_get_chan_by_scid(conn, cid);
  96         if (c)
  97                 l2cap_chan_lock(c);
  98         mutex_unlock(&conn->chan_lock);
  99
 100         return c;
 101 }
 102
 103 /* Find channel with given DCID.
 104  * Returns locked channel.
 105  */
 106 static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
 107                                                  u16 cid)
 108 {
 109         struct l2cap_chan *c;
 110
 111         mutex_lock(&conn->chan_lock);
 112         c = __l2cap_get_chan_by_dcid(conn, cid);
 113         if (c)
 114                 l2cap_chan_lock(c);
 115         mutex_unlock(&conn->chan_lock);
 116
 117         return c;
 118 }
 119
 120 static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
 121                                                     u8 ident)
 122 {
 123         struct l2cap_chan *c;
 124
 125         list_for_each_entry(c, &conn->chan_l, list) {
 126                 if (c->ident == ident)
 127                         return c;
 128         }
 129         return NULL;
 130 }
 131
 132 static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
 133                                                   u8 ident)
 134 {
 135         struct l2cap_chan *c;
 136
 137         mutex_lock(&conn->chan_lock);
 138         c = __l2cap_get_chan_by_ident(conn, ident);
 139         if (c)
 140                 l2cap_chan_lock(c);
 141         mutex_unlock(&conn->chan_lock);
 142
 143         return c;
 144 }
 145
 146 static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
 147 {
 148         struct l2cap_chan *c;
 149
 150         list_for_each_entry(c, &chan_list, global_l) {
 151                 if (c->sport == psm && !bacmp(&bt_sk(c->sk)->src, src))
 152                         return c;
 153         }
 154         return NULL;
 155 }
 156
 157 int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
 158 {
 159         int err;
 160
 161         write_lock(&chan_list_lock);
 162
 163         if (psm && __l2cap_global_chan_by_addr(psm, src)) {
 164                 err = -EADDRINUSE;
 165                 goto done;
 166         }
 167
 168         if (psm) {
 169                 chan->psm = psm;
 170                 chan->sport = psm;
 171                 err = 0;
 172         } else {
 173                 u16 p;
 174
 175                 err = -EINVAL;
 176                 for (p = 0x1001; p < 0x1100; p += 2)
 177                         if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
 178                                 chan->psm   = cpu_to_le16(p);
 179                                 chan->sport = cpu_to_le16(p);
 180                                 err = 0;
 181                                 break;
 182                         }
 183         }
 184
 185 done:
 186         write_unlock(&chan_list_lock);
 187         return err;
 188 }
 189
 190 int l2cap_add_scid(struct l2cap_chan *chan,  __u16 scid)
 191 {
 192         write_lock(&chan_list_lock);
 193
 194         chan->scid = scid;
 195
 196         write_unlock(&chan_list_lock);
 197
 198         return 0;
 199 }
 200
 201 static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
 202 {
 203         u16 cid = L2CAP_CID_DYN_START;
 204
 205         for (; cid < L2CAP_CID_DYN_END; cid++) {
 206                 if (!__l2cap_get_chan_by_scid(conn, cid))
 207                         return cid;
 208         }
 209
 210         return 0;
 211 }
 212
 213 static void __l2cap_state_change(struct l2cap_chan *chan, int state)
 214 {
 215         BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
 216                state_to_string(state));
 217
 218         chan->state = state;
 219         chan->ops->state_change(chan, state);
 220 }
 221
 222 static void l2cap_state_change(struct l2cap_chan *chan, int state)
 223 {
 224         struct sock *sk = chan->sk;
 225
 226         lock_sock(sk);
 227         __l2cap_state_change(chan, state);
 228         release_sock(sk);
 229 }
 230
 231 static inline void __l2cap_chan_set_err(struct l2cap_chan *chan, int err)
 232 {
 233         struct sock *sk = chan->sk;
 234
 235         sk->sk_err = err;
 236 }
 237
 238 static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
 239 {
 240         struct sock *sk = chan->sk;
 241
 242         lock_sock(sk);
 243         __l2cap_chan_set_err(chan, err);
 244         release_sock(sk);
 245 }
 246
 247 static void __set_retrans_timer(struct l2cap_chan *chan)
 248 {
 249         if (!delayed_work_pending(&chan->monitor_timer) &&
 250             chan->retrans_timeout) {
 251                 l2cap_set_timer(chan, &chan->retrans_timer,
 252                                 msecs_to_jiffies(chan->retrans_timeout));
 253         }
 254 }
 255
 256 static void __set_monitor_timer(struct l2cap_chan *chan)
 257 {
 258         __clear_retrans_timer(chan);
 259         if (chan->monitor_timeout) {
 260                 l2cap_set_timer(chan, &chan->monitor_timer,
 261                                 msecs_to_jiffies(chan->monitor_timeout));
 262         }
 263 }
 264
 265 static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
 266                                                u16 seq)
 267 {
 268         struct sk_buff *skb;
 269
 270         skb_queue_walk(head, skb) {
 271                 if (bt_cb(skb)->control.txseq == seq)
 272                         return skb;
 273         }
 274
 275         return NULL;
 276 }
 277
 278 /* ---- L2CAP sequence number lists ---- */
 279
 280 /* For ERTM, ordered lists of sequence numbers must be tracked for
 281  * SREJ requests that are received and for frames that are to be
 282  * retransmitted. These seq_list functions implement a singly-linked
 283  * list in an array, where membership in the list can also be checked
 284  * in constant time. Items can also be added to the tail of the list
 285  * and removed from the head in constant time, without further memory
 286  * allocs or frees.
 287  */
 288
 289 static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
 290 {
 291         size_t alloc_size, i;
 292
 293         /* Allocated size is a power of 2 to map sequence numbers
 294          * (which may be up to 14 bits) in to a smaller array that is
 295          * sized for the negotiated ERTM transmit windows.
 296          */
 297         alloc_size = roundup_pow_of_two(size);
 298
 299         seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
 300         if (!seq_list->list)
 301                 return -ENOMEM;
 302
 303         seq_list->mask = alloc_size - 1;
 304         seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 305         seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 306         for (i = 0; i < alloc_size; i++)
 307                 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
 308
 309         return 0;
 310 }
 311
 312 static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
 313 {
 314         kfree(seq_list->list);
 315 }
 316
 317 static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
 318                                            u16 seq)
 319 {
 320         /* Constant-time check for list membership */
 321         return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
 322 }
 323
 324 static u16 l2cap_seq_list_remove(struct l2cap_seq_list *seq_list, u16 seq)
 325 {
 326         u16 mask = seq_list->mask;
 327
 328         if (seq_list->head == L2CAP_SEQ_LIST_CLEAR) {
 329                 /* In case someone tries to pop the head of an empty list */
 330                 return L2CAP_SEQ_LIST_CLEAR;
 331         } else if (seq_list->head == seq) {
 332                 /* Head can be removed in constant time */
 333                 seq_list->head = seq_list->list[seq & mask];
 334                 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
 335
 336                 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
 337                         seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 338                         seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 339                 }
 340         } else {
 341                 /* Walk the list to find the sequence number */
 342                 u16 prev = seq_list->head;
 343                 while (seq_list->list[prev & mask] != seq) {
 344                         prev = seq_list->list[prev & mask];
 345                         if (prev == L2CAP_SEQ_LIST_TAIL)
 346                                 return L2CAP_SEQ_LIST_CLEAR;
 347                 }
 348
 349                 /* Unlink the number from the list and clear it */
 350                 seq_list->list[prev & mask] = seq_list->list[seq & mask];
 351                 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
 352                 if (seq_list->tail == seq)
 353                         seq_list->tail = prev;
 354         }
 355         return seq;
 356 }
 357
 358 static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
 359 {
 360         /* Remove the head in constant time */
 361         return l2cap_seq_list_remove(seq_list, seq_list->head);
 362 }
 363
 364 static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
 365 {
 366         u16 i;
 367
 368         if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
 369                 return;
 370
 371         for (i = 0; i <= seq_list->mask; i++)
 372                 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
 373
 374         seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 375         seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 376 }
 377
 378 static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
 379 {
 380         u16 mask = seq_list->mask;
 381
 382         /* All appends happen in constant time */
 383
 384         if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
 385                 return;
 386
 387         if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
 388                 seq_list->head = seq;
 389         else
 390                 seq_list->list[seq_list->tail & mask] = seq;
 391
 392         seq_list->tail = seq;
 393         seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
 394 }
 395
 396 static void l2cap_chan_timeout(struct work_struct *work)
 397 {
 398         struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
 399                                                chan_timer.work);
 400         struct l2cap_conn *conn = chan->conn;
 401         int reason;
 402
 403         BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
 404
 405         mutex_lock(&conn->chan_lock);
 406         l2cap_chan_lock(chan);
 407
 408         if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
 409                 reason = ECONNREFUSED;
 410         else if (chan->state == BT_CONNECT &&
 411                  chan->sec_level != BT_SECURITY_SDP)
 412                 reason = ECONNREFUSED;
 413         else
 414                 reason = ETIMEDOUT;
 415
 416         l2cap_chan_close(chan, reason);
 417
 418         l2cap_chan_unlock(chan);
 419
 420         chan->ops->close(chan);
 421         mutex_unlock(&conn->chan_lock);
 422
 423         l2cap_chan_put(chan);
 424 }
 425
 426 struct l2cap_chan *l2cap_chan_create(void)
 427 {
 428         struct l2cap_chan *chan;
 429
 430         chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
 431         if (!chan)
 432                 return NULL;
 433
 434         mutex_init(&chan->lock);
 435
 436         write_lock(&chan_list_lock);
 437         list_add(&chan->global_l, &chan_list);
 438         write_unlock(&chan_list_lock);
 439
 440         INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
 441
 442         chan->state = BT_OPEN;
 443
 444         kref_init(&chan->kref);
 445
 446         /* This flag is cleared in l2cap_chan_ready() */
 447         set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
 448
 449         BT_DBG("chan %p", chan);
 450
 451         return chan;
 452 }
 453
 454 static void l2cap_chan_destroy(struct kref *kref)
 455 {
 456         struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
 457
 458         BT_DBG("chan %p", chan);
 459
 460         write_lock(&chan_list_lock);
 461         list_del(&chan->global_l);
 462         write_unlock(&chan_list_lock);
 463
 464         kfree(chan);
 465 }
 466
 467 void l2cap_chan_hold(struct l2cap_chan *c)
 468 {
 469         BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
 470
 471         kref_get(&c->kref);
 472 }
 473
 474 void l2cap_chan_put(struct l2cap_chan *c)
 475 {
 476         BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
 477
 478         kref_put(&c->kref, l2cap_chan_destroy);
 479 }
 480
 481 void l2cap_chan_set_defaults(struct l2cap_chan *chan)
 482 {
 483         chan->fcs  = L2CAP_FCS_CRC16;
 484         chan->max_tx = L2CAP_DEFAULT_MAX_TX;
 485         chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
 486         chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
 487         chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
 488         chan->sec_level = BT_SECURITY_LOW;
 489
 490         set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 491 }
 492
 493 void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 494 {
 495         BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
 496                __le16_to_cpu(chan->psm), chan->dcid);
 497
 498         conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
 499
 500         chan->conn = conn;
 501
 502         switch (chan->chan_type) {
 503         case L2CAP_CHAN_CONN_ORIENTED:
 504                 if (conn->hcon->type == LE_LINK) {
 505                         /* LE connection */
 506                         chan->omtu = L2CAP_DEFAULT_MTU;
 507                         if (chan->dcid == L2CAP_CID_ATT)
 508                                 chan->scid = L2CAP_CID_ATT;
 509                         else
 510                                 chan->scid = l2cap_alloc_cid(conn);
 511                 } else {
 512                         /* Alloc CID for connection-oriented socket */
 513                         chan->scid = l2cap_alloc_cid(conn);
 514                         chan->omtu = L2CAP_DEFAULT_MTU;
 515                 }
 516                 break;
 517
 518         case L2CAP_CHAN_CONN_LESS:
 519                 /* Connectionless socket */
 520                 chan->scid = L2CAP_CID_CONN_LESS;
 521                 chan->dcid = L2CAP_CID_CONN_LESS;
 522                 chan->omtu = L2CAP_DEFAULT_MTU;
 523                 break;
 524
 525         case L2CAP_CHAN_CONN_FIX_A2MP:
 526                 chan->scid = L2CAP_CID_A2MP;
 527                 chan->dcid = L2CAP_CID_A2MP;
 528                 chan->omtu = L2CAP_A2MP_DEFAULT_MTU;
 529                 chan->imtu = L2CAP_A2MP_DEFAULT_MTU;
 530                 break;
 531
 532         default:
 533                 /* Raw socket can send/recv signalling messages only */
 534                 chan->scid = L2CAP_CID_SIGNALING;
 535                 chan->dcid = L2CAP_CID_SIGNALING;
 536                 chan->omtu = L2CAP_DEFAULT_MTU;
 537         }
 538
 539         chan->local_id          = L2CAP_BESTEFFORT_ID;
 540         chan->local_stype       = L2CAP_SERV_BESTEFFORT;
 541         chan->local_msdu        = L2CAP_DEFAULT_MAX_SDU_SIZE;
 542         chan->local_sdu_itime   = L2CAP_DEFAULT_SDU_ITIME;
 543         chan->local_acc_lat     = L2CAP_DEFAULT_ACC_LAT;
 544         chan->local_flush_to    = L2CAP_EFS_DEFAULT_FLUSH_TO;
 545
 546         l2cap_chan_hold(chan);
 547
 548         hci_conn_hold(conn->hcon);
 549
 550         list_add(&chan->list, &conn->chan_l);
 551 }
 552
 553 void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 554 {
 555         mutex_lock(&conn->chan_lock);
 556         __l2cap_chan_add(conn, chan);
 557         mutex_unlock(&conn->chan_lock);
 558 }
 559
 560 void l2cap_chan_del(struct l2cap_chan *chan, int err)
 561 {
 562         struct l2cap_conn *conn = chan->conn;
 563
 564         __clear_chan_timer(chan);
 565
 566         BT_DBG("chan %p, conn %p, err %d", chan, conn, err);
 567
 568         if (conn) {
 569                 struct amp_mgr *mgr = conn->hcon->amp_mgr;
 570                 /* Delete from channel list */
 571                 list_del(&chan->list);
 572
 573                 l2cap_chan_put(chan);
 574
 575                 chan->conn = NULL;
 576
 577                 if (chan->chan_type != L2CAP_CHAN_CONN_FIX_A2MP)
 578                         hci_conn_drop(conn->hcon);
 579
 580                 if (mgr && mgr->bredr_chan == chan)
 581                         mgr->bredr_chan = NULL;
 582         }
 583
 584         if (chan->hs_hchan) {
 585                 struct hci_chan *hs_hchan = chan->hs_hchan;
 586
 587                 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
 588                 amp_disconnect_logical_link(hs_hchan);
 589         }
 590
 591         chan->ops->teardown(chan, err);
 592
 593         if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
 594                 return;
 595
 596         switch(chan->mode) {
 597         case L2CAP_MODE_BASIC:
 598                 break;
 599
 600         case L2CAP_MODE_ERTM:
 601                 __clear_retrans_timer(chan);
 602                 __clear_monitor_timer(chan);
 603                 __clear_ack_timer(chan);
 604
 605                 skb_queue_purge(&chan->srej_q);
 606
 607                 l2cap_seq_list_free(&chan->srej_list);
 608                 l2cap_seq_list_free(&chan->retrans_list);
 609
 610                 /* fall through */
 611
 612         case L2CAP_MODE_STREAMING:
 613                 skb_queue_purge(&chan->tx_q);
 614                 break;
 615         }
 616
 617         return;
 618 }
 619
 620 void l2cap_chan_close(struct l2cap_chan *chan, int reason)
 621 {
 622         struct l2cap_conn *conn = chan->conn;
 623         struct sock *sk = chan->sk;
 624
 625         BT_DBG("chan %p state %s sk %p", chan, state_to_string(chan->state),
 626                sk);
 627
 628         switch (chan->state) {
 629         case BT_LISTEN:
 630                 chan->ops->teardown(chan, 0);
 631                 break;
 632
 633         case BT_CONNECTED:
 634         case BT_CONFIG:
 635                 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED &&
 636                     conn->hcon->type == ACL_LINK) {
 637                         __set_chan_timer(chan, sk->sk_sndtimeo);
 638                         l2cap_send_disconn_req(chan, reason);
 639                 } else
 640                         l2cap_chan_del(chan, reason);
 641                 break;
 642
 643         case BT_CONNECT2:
 644                 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED &&
 645                     conn->hcon->type == ACL_LINK) {
 646                         struct l2cap_conn_rsp rsp;
 647                         __u16 result;
 648
 649                         if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))
 650                                 result = L2CAP_CR_SEC_BLOCK;
 651                         else
 652                                 result = L2CAP_CR_BAD_PSM;
 653                         l2cap_state_change(chan, BT_DISCONN);
 654
 655                         rsp.scid   = cpu_to_le16(chan->dcid);
 656                         rsp.dcid   = cpu_to_le16(chan->scid);
 657                         rsp.result = cpu_to_le16(result);
 658                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
 659                         l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
 660                                        sizeof(rsp), &rsp);
 661                 }
 662
 663                 l2cap_chan_del(chan, reason);
 664                 break;
 665
 666         case BT_CONNECT:
 667         case BT_DISCONN:
 668                 l2cap_chan_del(chan, reason);
 669                 break;
 670
 671         default:
 672                 chan->ops->teardown(chan, 0);
 673                 break;
 674         }
 675 }
 676
 677 static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
 678 {
 679         if (chan->chan_type == L2CAP_CHAN_RAW) {
 680                 switch (chan->sec_level) {
 681                 case BT_SECURITY_HIGH:
 682                         return HCI_AT_DEDICATED_BONDING_MITM;
 683                 case BT_SECURITY_MEDIUM:
 684                         return HCI_AT_DEDICATED_BONDING;
 685                 default:
 686                         return HCI_AT_NO_BONDING;
 687                 }
 688         } else if (chan->psm == __constant_cpu_to_le16(L2CAP_PSM_SDP)) {
 689                 if (chan->sec_level == BT_SECURITY_LOW)
 690                         chan->sec_level = BT_SECURITY_SDP;
 691
 692                 if (chan->sec_level == BT_SECURITY_HIGH)
 693                         return HCI_AT_NO_BONDING_MITM;
 694                 else
 695                         return HCI_AT_NO_BONDING;
 696         } else {
 697                 switch (chan->sec_level) {
 698                 case BT_SECURITY_HIGH:
 699                         return HCI_AT_GENERAL_BONDING_MITM;
 700                 case BT_SECURITY_MEDIUM:
 701                         return HCI_AT_GENERAL_BONDING;
 702                 default:
 703                         return HCI_AT_NO_BONDING;
 704                 }
 705         }
 706 }
 707
 708 /* Service level security */
 709 int l2cap_chan_check_security(struct l2cap_chan *chan)
 710 {
 711         struct l2cap_conn *conn = chan->conn;
 712         __u8 auth_type;
 713
 714         auth_type = l2cap_get_auth_type(chan);
 715
 716         return hci_conn_security(conn->hcon, chan->sec_level, auth_type);
 717 }
 718
 719 static u8 l2cap_get_ident(struct l2cap_conn *conn)
 720 {
 721         u8 id;
 722
 723         /* Get next available identificator.
 724          *    1 - 128 are used by kernel.
 725          *  129 - 199 are reserved.
 726          *  200 - 254 are used by utilities like l2ping, etc.
 727          */
 728
 729         spin_lock(&conn->lock);
 730
 731         if (++conn->tx_ident > 128)
 732                 conn->tx_ident = 1;
 733
 734         id = conn->tx_ident;
 735
 736         spin_unlock(&conn->lock);
 737
 738         return id;
 739 }
 740
 741 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
 742                            void *data)
 743 {
 744         struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
 745         u8 flags;
 746
 747         BT_DBG("code 0x%2.2x", code);
 748
 749         if (!skb)
 750                 return;
 751
 752         if (lmp_no_flush_capable(conn->hcon->hdev))
 753                 flags = ACL_START_NO_FLUSH;
 754         else
 755                 flags = ACL_START;
 756
 757         bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
 758         skb->priority = HCI_PRIO_MAX;
 759
 760         hci_send_acl(conn->hchan, skb, flags);
 761 }
 762
 763 static bool __chan_is_moving(struct l2cap_chan *chan)
 764 {
 765         return chan->move_state != L2CAP_MOVE_STABLE &&
 766                chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
 767 }
 768
 769 static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
 770 {
 771         struct hci_conn *hcon = chan->conn->hcon;
 772         u16 flags;
 773
 774         BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
 775                skb->priority);
 776
 777         if (chan->hs_hcon && !__chan_is_moving(chan)) {
 778                 if (chan->hs_hchan)
 779                         hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
 780                 else
 781                         kfree_skb(skb);
 782
 783                 return;
 784         }
 785
 786         if (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
 787             lmp_no_flush_capable(hcon->hdev))
 788                 flags = ACL_START_NO_FLUSH;
 789         else
 790                 flags = ACL_START;
 791
 792         bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 793         hci_send_acl(chan->conn->hchan, skb, flags);
 794 }
 795
 796 static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
 797 {
 798         control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
 799         control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
 800
 801         if (enh & L2CAP_CTRL_FRAME_TYPE) {
 802                 /* S-Frame */
 803                 control->sframe = 1;
 804                 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
 805                 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
 806
 807                 control->sar = 0;
 808                 control->txseq = 0;
 809         } else {
 810                 /* I-Frame */
 811                 control->sframe = 0;
 812                 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
 813                 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
 814
 815                 control->poll = 0;
 816                 control->super = 0;
 817         }
 818 }
 819
 820 static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
 821 {
 822         control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
 823         control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
 824
 825         if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
 826                 /* S-Frame */
 827                 control->sframe = 1;
 828                 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
 829                 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
 830
 831                 control->sar = 0;
 832                 control->txseq = 0;
 833         } else {
 834                 /* I-Frame */
 835                 control->sframe = 0;
 836                 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
 837                 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
 838
 839                 control->poll = 0;
 840                 control->super = 0;
 841         }
 842 }
 843
 844 static inline void __unpack_control(struct l2cap_chan *chan,
 845                                     struct sk_buff *skb)
 846 {
 847         if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
 848                 __unpack_extended_control(get_unaligned_le32(skb->data),
 849                                           &bt_cb(skb)->control);
 850                 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
 851         } else {
 852                 __unpack_enhanced_control(get_unaligned_le16(skb->data),
 853                                           &bt_cb(skb)->control);
 854                 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
 855         }
 856 }
 857
 858 static u32 __pack_extended_control(struct l2cap_ctrl *control)
 859 {
 860         u32 packed;
 861
 862         packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
 863         packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
 864
 865         if (control->sframe) {
 866                 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
 867                 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
 868                 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
 869         } else {
 870                 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
 871                 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
 872         }
 873
 874         return packed;
 875 }
 876
 877 static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
 878 {
 879         u16 packed;
 880
 881         packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
 882         packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
 883
 884         if (control->sframe) {
 885                 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
 886                 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
 887                 packed |= L2CAP_CTRL_FRAME_TYPE;
 888         } else {
 889                 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
 890                 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
 891         }
 892
 893         return packed;
 894 }
 895
 896 static inline void __pack_control(struct l2cap_chan *chan,
 897                                   struct l2cap_ctrl *control,
 898                                   struct sk_buff *skb)
 899 {
 900         if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
 901                 put_unaligned_le32(__pack_extended_control(control),
 902                                    skb->data + L2CAP_HDR_SIZE);
 903         } else {
 904                 put_unaligned_le16(__pack_enhanced_control(control),
 905                                    skb->data + L2CAP_HDR_SIZE);
 906         }
 907 }
 908
 909 static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
 910 {
 911         if (test_bit(FLAG_EXT_CTRL, &chan->flags))
 912                 return L2CAP_EXT_HDR_SIZE;
 913         else
 914                 return L2CAP_ENH_HDR_SIZE;
 915 }
 916
 917 static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
 918                                                u32 control)
 919 {
 920         struct sk_buff *skb;
 921         struct l2cap_hdr *lh;
 922         int hlen = __ertm_hdr_size(chan);
 923
 924         if (chan->fcs == L2CAP_FCS_CRC16)
 925                 hlen += L2CAP_FCS_SIZE;
 926
 927         skb = bt_skb_alloc(hlen, GFP_KERNEL);
 928
 929         if (!skb)
 930                 return ERR_PTR(-ENOMEM);
 931
 932         lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
 933         lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
 934         lh->cid = cpu_to_le16(chan->dcid);
 935
 936         if (test_bit(FLAG_EXT_CTRL, &chan->flags))
 937                 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
 938         else
 939                 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
 940
 941         if (chan->fcs == L2CAP_FCS_CRC16) {
 942                 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
 943                 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
 944         }
 945
 946         skb->priority = HCI_PRIO_MAX;
 947         return skb;
 948 }
 949
 950 static void l2cap_send_sframe(struct l2cap_chan *chan,
 951                               struct l2cap_ctrl *control)
 952 {
 953         struct sk_buff *skb;
 954         u32 control_field;
 955
 956         BT_DBG("chan %p, control %p", chan, control);
 957
 958         if (!control->sframe)
 959                 return;
 960
 961         if (__chan_is_moving(chan))
 962                 return;
 963
 964         if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
 965             !control->poll)
 966                 control->final = 1;
 967
 968         if (control->super == L2CAP_SUPER_RR)
 969                 clear_bit(CONN_RNR_SENT, &chan->conn_state);
 970         else if (control->super == L2CAP_SUPER_RNR)
 971                 set_bit(CONN_RNR_SENT, &chan->conn_state);
 972
 973         if (control->super != L2CAP_SUPER_SREJ) {
 974                 chan->last_acked_seq = control->reqseq;
 975                 __clear_ack_timer(chan);
 976         }
 977
 978         BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
 979                control->final, control->poll, control->super);
 980
 981         if (test_bit(FLAG_EXT_CTRL, &chan->flags))
 982                 control_field = __pack_extended_control(control);
 983         else
 984                 control_field = __pack_enhanced_control(control);
 985
 986         skb = l2cap_create_sframe_pdu(chan, control_field);
 987         if (!IS_ERR(skb))
 988                 l2cap_do_send(chan, skb);
 989 }
 990
 991 static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
 992 {
 993         struct l2cap_ctrl control;
 994
 995         BT_DBG("chan %p, poll %d", chan, poll);
 996
 997         memset(&control, 0, sizeof(control));
 998         control.sframe = 1;
 999         control.poll = poll;
1000
1001         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1002                 control.super = L2CAP_SUPER_RNR;
1003         else
1004                 control.super = L2CAP_SUPER_RR;
1005
1006         control.reqseq = chan->buffer_seq;
1007         l2cap_send_sframe(chan, &control);
1008 }
1009
1010 static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1011 {
1012         return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1013 }
1014
1015 static bool __amp_capable(struct l2cap_chan *chan)
1016 {
1017         struct l2cap_conn *conn = chan->conn;
1018
1019         if (enable_hs &&
1020             hci_amp_capable() &&
1021             chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED &&
1022             conn->fixed_chan_mask & L2CAP_FC_A2MP)
1023                 return true;
1024         else
1025                 return false;
1026 }
1027
1028 static bool l2cap_check_efs(struct l2cap_chan *chan)
1029 {
1030         /* Check EFS parameters */
1031         return true;
1032 }
1033
1034 void l2cap_send_conn_req(struct l2cap_chan *chan)
1035 {
1036         struct l2cap_conn *conn = chan->conn;
1037         struct l2cap_conn_req req;
1038
1039         req.scid = cpu_to_le16(chan->scid);
1040         req.psm  = chan->psm;
1041
1042         chan->ident = l2cap_get_ident(conn);
1043
1044         set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1045
1046         l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1047 }
1048
1049 static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1050 {
1051         struct l2cap_create_chan_req req;
1052         req.scid = cpu_to_le16(chan->scid);
1053         req.psm  = chan->psm;
1054         req.amp_id = amp_id;
1055
1056         chan->ident = l2cap_get_ident(chan->conn);
1057
1058         l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1059                        sizeof(req), &req);
1060 }
1061
1062 static void l2cap_move_setup(struct l2cap_chan *chan)
1063 {
1064         struct sk_buff *skb;
1065
1066         BT_DBG("chan %p", chan);
1067
1068         if (chan->mode != L2CAP_MODE_ERTM)
1069                 return;
1070
1071         __clear_retrans_timer(chan);
1072         __clear_monitor_timer(chan);
1073         __clear_ack_timer(chan);
1074
1075         chan->retry_count = 0;
1076         skb_queue_walk(&chan->tx_q, skb) {
1077                 if (bt_cb(skb)->control.retries)
1078                         bt_cb(skb)->control.retries = 1;
1079                 else
1080                         break;
1081         }
1082
1083         chan->expected_tx_seq = chan->buffer_seq;
1084
1085         clear_bit(CONN_REJ_ACT, &chan->conn_state);
1086         clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1087         l2cap_seq_list_clear(&chan->retrans_list);
1088         l2cap_seq_list_clear(&chan->srej_list);
1089         skb_queue_purge(&chan->srej_q);
1090
1091         chan->tx_state = L2CAP_TX_STATE_XMIT;
1092         chan->rx_state = L2CAP_RX_STATE_MOVE;
1093
1094         set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1095 }
1096
1097 static void l2cap_move_done(struct l2cap_chan *chan)
1098 {
1099         u8 move_role = chan->move_role;
1100         BT_DBG("chan %p", chan);
1101
1102         chan->move_state = L2CAP_MOVE_STABLE;
1103         chan->move_role = L2CAP_MOVE_ROLE_NONE;
1104
1105         if (chan->mode != L2CAP_MODE_ERTM)
1106                 return;
1107
1108         switch (move_role) {
1109         case L2CAP_MOVE_ROLE_INITIATOR:
1110                 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1111                 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1112                 break;
1113         case L2CAP_MOVE_ROLE_RESPONDER:
1114                 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1115                 break;
1116         }
1117 }
1118
1119 static void l2cap_chan_ready(struct l2cap_chan *chan)
1120 {
1121         /* This clears all conf flags, including CONF_NOT_COMPLETE */
1122         chan->conf_state = 0;
1123         __clear_chan_timer(chan);
1124
1125         chan->state = BT_CONNECTED;
1126
1127         chan->ops->ready(chan);
1128 }
1129
1130 static void l2cap_start_connection(struct l2cap_chan *chan)
1131 {
1132         if (__amp_capable(chan)) {
1133                 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1134                 a2mp_discover_amp(chan);
1135         } else {
1136                 l2cap_send_conn_req(chan);
1137         }
1138 }
1139
1140 static void l2cap_do_start(struct l2cap_chan *chan)
1141 {
1142         struct l2cap_conn *conn = chan->conn;
1143
1144         if (conn->hcon->type == LE_LINK) {
1145                 l2cap_chan_ready(chan);
1146                 return;
1147         }
1148
1149         if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) {
1150                 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1151                         return;
1152
1153                 if (l2cap_chan_check_security(chan) &&
1154                     __l2cap_no_conn_pending(chan)) {
1155                         l2cap_start_connection(chan);
1156                 }
1157         } else {
1158                 struct l2cap_info_req req;
1159                 req.type = __constant_cpu_to_le16(L2CAP_IT_FEAT_MASK);
1160
1161                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1162                 conn->info_ident = l2cap_get_ident(conn);
1163
1164                 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1165
1166                 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1167                                sizeof(req), &req);
1168         }
1169 }
1170
1171 static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1172 {
1173         u32 local_feat_mask = l2cap_feat_mask;
1174         if (!disable_ertm)
1175                 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1176
1177         switch (mode) {
1178         case L2CAP_MODE_ERTM:
1179                 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1180         case L2CAP_MODE_STREAMING:
1181                 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1182         default:
1183                 return 0x00;
1184         }
1185 }
1186
1187 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1188 {
1189         struct sock *sk = chan->sk;
1190         struct l2cap_conn *conn = chan->conn;
1191         struct l2cap_disconn_req req;
1192
1193         if (!conn)
1194                 return;
1195
1196         if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1197                 __clear_retrans_timer(chan);
1198                 __clear_monitor_timer(chan);
1199                 __clear_ack_timer(chan);
1200         }
1201
1202         if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
1203                 l2cap_state_change(chan, BT_DISCONN);
1204                 return;
1205         }
1206
1207         req.dcid = cpu_to_le16(chan->dcid);
1208         req.scid = cpu_to_le16(chan->scid);
1209         l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1210                        sizeof(req), &req);
1211
1212         lock_sock(sk);
1213         __l2cap_state_change(chan, BT_DISCONN);
1214         __l2cap_chan_set_err(chan, err);
1215         release_sock(sk);
1216 }
1217
1218 /* ---- L2CAP connections ---- */
1219 static void l2cap_conn_start(struct l2cap_conn *conn)
1220 {
1221         struct l2cap_chan *chan, *tmp;
1222
1223         BT_DBG("conn %p", conn);
1224
1225         mutex_lock(&conn->chan_lock);
1226
1227         list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1228                 struct sock *sk = chan->sk;
1229
1230                 l2cap_chan_lock(chan);
1231
1232                 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1233                         l2cap_chan_unlock(chan);
1234                         continue;
1235                 }
1236
1237                 if (chan->state == BT_CONNECT) {
1238                         if (!l2cap_chan_check_security(chan) ||
1239                             !__l2cap_no_conn_pending(chan)) {
1240                                 l2cap_chan_unlock(chan);
1241                                 continue;
1242                         }
1243
1244                         if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1245                             && test_bit(CONF_STATE2_DEVICE,
1246                                         &chan->conf_state)) {
1247                                 l2cap_chan_close(chan, ECONNRESET);
1248                                 l2cap_chan_unlock(chan);
1249                                 continue;
1250                         }
1251
1252                         l2cap_start_connection(chan);
1253
1254                 } else if (chan->state == BT_CONNECT2) {
1255                         struct l2cap_conn_rsp rsp;
1256                         char buf[128];
1257                         rsp.scid = cpu_to_le16(chan->dcid);
1258                         rsp.dcid = cpu_to_le16(chan->scid);
1259
1260                         if (l2cap_chan_check_security(chan)) {
1261                                 lock_sock(sk);
1262                                 if (test_bit(BT_SK_DEFER_SETUP,
1263                                              &bt_sk(sk)->flags)) {
1264                                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_PEND);
1265                                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1266                                         chan->ops->defer(chan);
1267
1268                                 } else {
1269                                         __l2cap_state_change(chan, BT_CONFIG);
1270                                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_SUCCESS);
1271                                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
1272                                 }
1273                                 release_sock(sk);
1274                         } else {
1275                                 rsp.result = __constant_cpu_to_le16(L2CAP_CR_PEND);
1276                                 rsp.status = __constant_cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1277                         }
1278
1279                         l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1280                                        sizeof(rsp), &rsp);
1281
1282                         if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1283                             rsp.result != L2CAP_CR_SUCCESS) {
1284                                 l2cap_chan_unlock(chan);
1285                                 continue;
1286                         }
1287
1288                         set_bit(CONF_REQ_SENT, &chan->conf_state);
1289                         l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1290                                        l2cap_build_conf_req(chan, buf), buf);
1291                         chan->num_conf_req++;
1292                 }
1293
1294                 l2cap_chan_unlock(chan);
1295         }
1296
1297         mutex_unlock(&conn->chan_lock);
1298 }
1299
1300 /* Find socket with cid and source/destination bdaddr.
1301  * Returns closest match, locked.
1302  */
1303 static struct l2cap_chan *l2cap_global_chan_by_scid(int state, u16 cid,
1304                                                     bdaddr_t *src,
1305                                                     bdaddr_t *dst)
1306 {
1307         struct l2cap_chan *c, *c1 = NULL;
1308
1309         read_lock(&chan_list_lock);
1310
1311         list_for_each_entry(c, &chan_list, global_l) {
1312                 struct sock *sk = c->sk;
1313
1314                 if (state && c->state != state)
1315                         continue;
1316
1317                 if (c->scid == cid) {
1318                         int src_match, dst_match;
1319                         int src_any, dst_any;
1320
1321                         /* Exact match. */
1322                         src_match = !bacmp(&bt_sk(sk)->src, src);
1323                         dst_match = !bacmp(&bt_sk(sk)->dst, dst);
1324                         if (src_match && dst_match) {
1325                                 read_unlock(&chan_list_lock);
1326                                 return c;
1327                         }
1328
1329                         /* Closest match */
1330                         src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
1331                         dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
1332                         if ((src_match && dst_any) || (src_any && dst_match) ||
1333                             (src_any && dst_any))
1334                                 c1 = c;
1335                 }
1336         }
1337
1338         read_unlock(&chan_list_lock);
1339
1340         return c1;
1341 }
1342
1343 static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1344 {
1345         struct sock *parent;
1346         struct l2cap_chan *chan, *pchan;
1347
1348         BT_DBG("");
1349
1350         /* Check if we have socket listening on cid */
1351         pchan = l2cap_global_chan_by_scid(BT_LISTEN, L2CAP_CID_ATT,
1352                                           conn->src, conn->dst);
1353         if (!pchan)
1354                 return;
1355
1356         /* Client ATT sockets should override the server one */
1357         if (__l2cap_get_chan_by_dcid(conn, L2CAP_CID_ATT))
1358                 return;
1359
1360         parent = pchan->sk;
1361
1362         lock_sock(parent);
1363
1364         chan = pchan->ops->new_connection(pchan);
1365         if (!chan)
1366                 goto clean;
1367
1368         chan->dcid = L2CAP_CID_ATT;
1369
1370         bacpy(&bt_sk(chan->sk)->src, conn->src);
1371         bacpy(&bt_sk(chan->sk)->dst, conn->dst);
1372
1373         __l2cap_chan_add(conn, chan);
1374
1375 clean:
1376         release_sock(parent);
1377 }
1378
1379 static void l2cap_conn_ready(struct l2cap_conn *conn)
1380 {
1381         struct l2cap_chan *chan;
1382         struct hci_conn *hcon = conn->hcon;
1383
1384         BT_DBG("conn %p", conn);
1385
1386         /* For outgoing pairing which doesn't necessarily have an
1387          * associated socket (e.g. mgmt_pair_device).
1388          */
1389         if (hcon->out && hcon->type == LE_LINK)
1390                 smp_conn_security(hcon, hcon->pending_sec_level);
1391
1392         mutex_lock(&conn->chan_lock);
1393
1394         if (hcon->type == LE_LINK)
1395                 l2cap_le_conn_ready(conn);
1396
1397         list_for_each_entry(chan, &conn->chan_l, list) {
1398
1399                 l2cap_chan_lock(chan);
1400
1401                 if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
1402                         l2cap_chan_unlock(chan);
1403                         continue;
1404                 }
1405
1406                 if (hcon->type == LE_LINK) {
1407                         if (smp_conn_security(hcon, chan->sec_level))
1408                                 l2cap_chan_ready(chan);
1409
1410                 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1411                         struct sock *sk = chan->sk;
1412                         __clear_chan_timer(chan);
1413                         lock_sock(sk);
1414                         __l2cap_state_change(chan, BT_CONNECTED);
1415                         sk->sk_state_change(sk);
1416                         release_sock(sk);
1417
1418                 } else if (chan->state == BT_CONNECT) {
1419                         l2cap_do_start(chan);
1420                 }
1421
1422                 l2cap_chan_unlock(chan);
1423         }
1424
1425         mutex_unlock(&conn->chan_lock);
1426 }
1427
1428 /* Notify sockets that we cannot guaranty reliability anymore */
1429 static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1430 {
1431         struct l2cap_chan *chan;
1432
1433         BT_DBG("conn %p", conn);
1434
1435         mutex_lock(&conn->chan_lock);
1436
1437         list_for_each_entry(chan, &conn->chan_l, list) {
1438                 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1439                         l2cap_chan_set_err(chan, err);
1440         }
1441
1442         mutex_unlock(&conn->chan_lock);
1443 }
1444
1445 static void l2cap_info_timeout(struct work_struct *work)
1446 {
1447         struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1448                                                info_timer.work);
1449
1450         conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1451         conn->info_ident = 0;
1452
1453         l2cap_conn_start(conn);
1454 }
1455
1456 /*
1457  * l2cap_user
1458  * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1459  * callback is called during registration. The ->remove callback is called
1460  * during unregistration.
1461  * An l2cap_user object can either be explicitly unregistered or when the
1462  * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1463  * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1464  * External modules must own a reference to the l2cap_conn object if they intend
1465  * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1466  * any time if they don't.
1467  */
1468
1469 int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1470 {
1471         struct hci_dev *hdev = conn->hcon->hdev;
1472         int ret;
1473
1474         /* We need to check whether l2cap_conn is registered. If it is not, we
1475          * must not register the l2cap_user. l2cap_conn_del() is unregisters
1476          * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1477          * relies on the parent hci_conn object to be locked. This itself relies
1478          * on the hci_dev object to be locked. So we must lock the hci device
1479          * here, too. */
1480
1481         hci_dev_lock(hdev);
1482
1483         if (user->list.next || user->list.prev) {
1484                 ret = -EINVAL;
1485                 goto out_unlock;
1486         }
1487
1488         /* conn->hchan is NULL after l2cap_conn_del() was called */
1489         if (!conn->hchan) {
1490                 ret = -ENODEV;
1491                 goto out_unlock;
1492         }
1493
1494         ret = user->probe(conn, user);
1495         if (ret)
1496                 goto out_unlock;
1497
1498         list_add(&user->list, &conn->users);
1499         ret = 0;
1500
1501 out_unlock:
1502         hci_dev_unlock(hdev);
1503         return ret;
1504 }
1505 EXPORT_SYMBOL(l2cap_register_user);
1506
1507 void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1508 {
1509         struct hci_dev *hdev = conn->hcon->hdev;
1510
1511         hci_dev_lock(hdev);
1512
1513         if (!user->list.next || !user->list.prev)
1514                 goto out_unlock;
1515
1516         list_del(&user->list);
1517         user->list.next = NULL;
1518         user->list.prev = NULL;
1519         user->remove(conn, user);
1520
1521 out_unlock:
1522         hci_dev_unlock(hdev);
1523 }
1524 EXPORT_SYMBOL(l2cap_unregister_user);
1525
1526 static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1527 {
1528         struct l2cap_user *user;
1529
1530         while (!list_empty(&conn->users)) {
1531                 user = list_first_entry(&conn->users, struct l2cap_user, list);
1532                 list_del(&user->list);
1533                 user->list.next = NULL;
1534                 user->list.prev = NULL;
1535                 user->remove(conn, user);
1536         }
1537 }
1538
1539 static void l2cap_conn_del(struct hci_conn *hcon, int err)
1540 {
1541         struct l2cap_conn *conn = hcon->l2cap_data;
1542         struct l2cap_chan *chan, *l;
1543
1544         if (!conn)
1545                 return;
1546
1547         BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1548
1549         kfree_skb(conn->rx_skb);
1550
1551         l2cap_unregister_all_users(conn);
1552
1553         mutex_lock(&conn->chan_lock);
1554
1555         /* Kill channels */
1556         list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1557                 l2cap_chan_hold(chan);
1558                 l2cap_chan_lock(chan);
1559
1560                 l2cap_chan_del(chan, err);
1561
1562                 l2cap_chan_unlock(chan);
1563
1564                 chan->ops->close(chan);
1565                 l2cap_chan_put(chan);
1566         }
1567
1568         mutex_unlock(&conn->chan_lock);
1569
1570         hci_chan_del(conn->hchan);
1571
1572         if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1573                 cancel_delayed_work_sync(&conn->info_timer);
1574
1575         if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags)) {
1576                 cancel_delayed_work_sync(&conn->security_timer);
1577                 smp_chan_destroy(conn);
1578         }
1579
1580         hcon->l2cap_data = NULL;
1581         conn->hchan = NULL;
1582         l2cap_conn_put(conn);
1583 }
1584
1585 static void security_timeout(struct work_struct *work)
1586 {
1587         struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1588                                                security_timer.work);
1589
1590         BT_DBG("conn %p", conn);
1591
1592         if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags)) {
1593                 smp_chan_destroy(conn);
1594                 l2cap_conn_del(conn->hcon, ETIMEDOUT);
1595         }
1596 }
1597
1598 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
1599 {
1600         struct l2cap_conn *conn = hcon->l2cap_data;
1601         struct hci_chan *hchan;
1602
1603         if (conn)
1604                 return conn;
1605
1606         hchan = hci_chan_create(hcon);
1607         if (!hchan)
1608                 return NULL;
1609
1610         conn = kzalloc(sizeof(struct l2cap_conn), GFP_KERNEL);
1611         if (!conn) {
1612                 hci_chan_del(hchan);
1613                 return NULL;
1614         }
1615
1616         kref_init(&conn->ref);
1617         hcon->l2cap_data = conn;
1618         conn->hcon = hcon;
1619         hci_conn_get(conn->hcon);
1620         conn->hchan = hchan;
1621
1622         BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
1623
1624         switch (hcon->type) {
1625         case LE_LINK:
1626                 if (hcon->hdev->le_mtu) {
1627                         conn->mtu = hcon->hdev->le_mtu;
1628                         break;
1629                 }
1630                 /* fall through */
1631         default:
1632                 conn->mtu = hcon->hdev->acl_mtu;
1633                 break;
1634         }
1635
1636         conn->src = &hcon->hdev->bdaddr;
1637         conn->dst = &hcon->dst;
1638
1639         conn->feat_mask = 0;
1640
1641         spin_lock_init(&conn->lock);
1642         mutex_init(&conn->chan_lock);
1643
1644         INIT_LIST_HEAD(&conn->chan_l);
1645         INIT_LIST_HEAD(&conn->users);
1646
1647         if (hcon->type == LE_LINK)
1648                 INIT_DELAYED_WORK(&conn->security_timer, security_timeout);
1649         else
1650                 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
1651
1652         conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
1653
1654         return conn;
1655 }
1656
1657 static void l2cap_conn_free(struct kref *ref)
1658 {
1659         struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1660
1661         hci_conn_put(conn->hcon);
1662         kfree(conn);
1663 }
1664
1665 void l2cap_conn_get(struct l2cap_conn *conn)
1666 {
1667         kref_get(&conn->ref);
1668 }
1669 EXPORT_SYMBOL(l2cap_conn_get);
1670
1671 void l2cap_conn_put(struct l2cap_conn *conn)
1672 {
1673         kref_put(&conn->ref, l2cap_conn_free);
1674 }
1675 EXPORT_SYMBOL(l2cap_conn_put);
1676
1677 /* ---- Socket interface ---- */
1678
1679 /* Find socket with psm and source / destination bdaddr.
1680  * Returns closest match.
1681  */
1682 static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1683                                                    bdaddr_t *src,
1684                                                    bdaddr_t *dst)
1685 {
1686         struct l2cap_chan *c, *c1 = NULL;
1687
1688         read_lock(&chan_list_lock);
1689
1690         list_for_each_entry(c, &chan_list, global_l) {
1691                 struct sock *sk = c->sk;
1692
1693                 if (state && c->state != state)
1694                         continue;
1695
1696                 if (c->psm == psm) {
1697                         int src_match, dst_match;
1698                         int src_any, dst_any;
1699
1700                         /* Exact match. */
1701                         src_match = !bacmp(&bt_sk(sk)->src, src);
1702                         dst_match = !bacmp(&bt_sk(sk)->dst, dst);
1703                         if (src_match && dst_match) {
1704                                 read_unlock(&chan_list_lock);
1705                                 return c;
1706                         }
1707
1708                         /* Closest match */
1709                         src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
1710                         dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
1711                         if ((src_match && dst_any) || (src_any && dst_match) ||
1712                             (src_any && dst_any))
1713                                 c1 = c;
1714                 }
1715         }
1716
1717         read_unlock(&chan_list_lock);
1718
1719         return c1;
1720 }
1721
1722 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
1723                        bdaddr_t *dst, u8 dst_type)
1724 {
1725         struct sock *sk = chan->sk;
1726         bdaddr_t *src = &bt_sk(sk)->src;
1727         struct l2cap_conn *conn;
1728         struct hci_conn *hcon;
1729         struct hci_dev *hdev;
1730         __u8 auth_type;
1731         int err;
1732
1733         BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", src, dst,
1734                dst_type, __le16_to_cpu(psm));
1735
1736         hdev = hci_get_route(dst, src);
1737         if (!hdev)
1738                 return -EHOSTUNREACH;
1739
1740         hci_dev_lock(hdev);
1741
1742         l2cap_chan_lock(chan);
1743
1744         /* PSM must be odd and lsb of upper byte must be 0 */
1745         if ((__le16_to_cpu(psm) & 0x0101) != 0x0001 && !cid &&
1746             chan->chan_type != L2CAP_CHAN_RAW) {
1747                 err = -EINVAL;
1748                 goto done;
1749         }
1750
1751         if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !(psm || cid)) {
1752                 err = -EINVAL;
1753                 goto done;
1754         }
1755
1756         switch (chan->mode) {
1757         case L2CAP_MODE_BASIC:
1758                 break;
1759         case L2CAP_MODE_ERTM:
1760         case L2CAP_MODE_STREAMING:
1761                 if (!disable_ertm)
1762                         break;
1763                 /* fall through */
1764         default:
1765                 err = -ENOTSUPP;
1766                 goto done;
1767         }
1768
1769         switch (chan->state) {
1770         case BT_CONNECT:
1771         case BT_CONNECT2:
1772         case BT_CONFIG:
1773                 /* Already connecting */
1774                 err = 0;
1775                 goto done;
1776
1777         case BT_CONNECTED:
1778                 /* Already connected */
1779                 err = -EISCONN;
1780                 goto done;
1781
1782         case BT_OPEN:
1783         case BT_BOUND:
1784                 /* Can connect */
1785                 break;
1786
1787         default:
1788                 err = -EBADFD;
1789                 goto done;
1790         }
1791
1792         /* Set destination address and psm */
1793         lock_sock(sk);
1794         bacpy(&bt_sk(sk)->dst, dst);
1795         release_sock(sk);
1796
1797         chan->psm = psm;
1798         chan->dcid = cid;
1799
1800         auth_type = l2cap_get_auth_type(chan);
1801
1802         if (bdaddr_type_is_le(dst_type))
1803                 hcon = hci_connect(hdev, LE_LINK, dst, dst_type,
1804                                    chan->sec_level, auth_type);
1805         else
1806                 hcon = hci_connect(hdev, ACL_LINK, dst, dst_type,
1807                                    chan->sec_level, auth_type);
1808
1809         if (IS_ERR(hcon)) {
1810                 err = PTR_ERR(hcon);
1811                 goto done;
1812         }
1813
1814         conn = l2cap_conn_add(hcon);
1815         if (!conn) {
1816                 hci_conn_drop(hcon);
1817                 err = -ENOMEM;
1818                 goto done;
1819         }
1820
1821         if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
1822                 hci_conn_drop(hcon);
1823                 err = -EBUSY;
1824                 goto done;
1825         }
1826
1827         /* Update source addr of the socket */
1828         bacpy(src, conn->src);
1829
1830         l2cap_chan_unlock(chan);
1831         l2cap_chan_add(conn, chan);
1832         l2cap_chan_lock(chan);
1833
1834         /* l2cap_chan_add takes its own ref so we can drop this one */
1835         hci_conn_drop(hcon);
1836
1837         l2cap_state_change(chan, BT_CONNECT);
1838         __set_chan_timer(chan, sk->sk_sndtimeo);
1839
1840         if (hcon->state == BT_CONNECTED) {
1841                 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1842                         __clear_chan_timer(chan);
1843                         if (l2cap_chan_check_security(chan))
1844                                 l2cap_state_change(chan, BT_CONNECTED);
1845                 } else
1846                         l2cap_do_start(chan);
1847         }
1848
1849         err = 0;
1850
1851 done:
1852         l2cap_chan_unlock(chan);
1853         hci_dev_unlock(hdev);
1854         hci_dev_put(hdev);
1855         return err;
1856 }
1857
1858 int __l2cap_wait_ack(struct sock *sk)
1859 {
1860         struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1861         DECLARE_WAITQUEUE(wait, current);
1862         int err = 0;
1863         int timeo = HZ/5;
1864
1865         add_wait_queue(sk_sleep(sk), &wait);
1866         set_current_state(TASK_INTERRUPTIBLE);
1867         while (chan->unacked_frames > 0 && chan->conn) {
1868                 if (!timeo)
1869                         timeo = HZ/5;
1870
1871                 if (signal_pending(current)) {
1872                         err = sock_intr_errno(timeo);
1873                         break;
1874                 }
1875
1876                 release_sock(sk);
1877                 timeo = schedule_timeout(timeo);
1878                 lock_sock(sk);
1879                 set_current_state(TASK_INTERRUPTIBLE);
1880
1881                 err = sock_error(sk);
1882                 if (err)
1883                         break;
1884         }
1885         set_current_state(TASK_RUNNING);
1886         remove_wait_queue(sk_sleep(sk), &wait);
1887         return err;
1888 }
1889
1890 static void l2cap_monitor_timeout(struct work_struct *work)
1891 {
1892         struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1893                                                monitor_timer.work);
1894
1895         BT_DBG("chan %p", chan);
1896
1897         l2cap_chan_lock(chan);
1898
1899         if (!chan->conn) {
1900                 l2cap_chan_unlock(chan);
1901                 l2cap_chan_put(chan);
1902                 return;
1903         }
1904
1905         l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1906
1907         l2cap_chan_unlock(chan);
1908         l2cap_chan_put(chan);
1909 }
1910
1911 static void l2cap_retrans_timeout(struct work_struct *work)
1912 {
1913         struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1914                                                retrans_timer.work);
1915
1916         BT_DBG("chan %p", chan);
1917
1918         l2cap_chan_lock(chan);
1919
1920         if (!chan->conn) {
1921                 l2cap_chan_unlock(chan);
1922                 l2cap_chan_put(chan);
1923                 return;
1924         }
1925
1926         l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1927         l2cap_chan_unlock(chan);
1928         l2cap_chan_put(chan);
1929 }
1930
1931 static void l2cap_streaming_send(struct l2cap_chan *chan,
1932                                  struct sk_buff_head *skbs)
1933 {
1934         struct sk_buff *skb;
1935         struct l2cap_ctrl *control;
1936
1937         BT_DBG("chan %p, skbs %p", chan, skbs);
1938
1939         if (__chan_is_moving(chan))
1940                 return;
1941
1942         skb_queue_splice_tail_init(skbs, &chan->tx_q);
1943
1944         while (!skb_queue_empty(&chan->tx_q)) {
1945
1946                 skb = skb_dequeue(&chan->tx_q);
1947
1948                 bt_cb(skb)->control.retries = 1;
1949                 control = &bt_cb(skb)->control;
1950
1951                 control->reqseq = 0;
1952                 control->txseq = chan->next_tx_seq;
1953
1954                 __pack_control(chan, control, skb);
1955
1956                 if (chan->fcs == L2CAP_FCS_CRC16) {
1957                         u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1958                         put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1959                 }
1960
1961                 l2cap_do_send(chan, skb);
1962
1963                 BT_DBG("Sent txseq %u", control->txseq);
1964
1965                 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1966                 chan->frames_sent++;
1967         }
1968 }
1969
1970 static int l2cap_ertm_send(struct l2cap_chan *chan)
1971 {
1972         struct sk_buff *skb, *tx_skb;
1973         struct l2cap_ctrl *control;
1974         int sent = 0;
1975
1976         BT_DBG("chan %p", chan);
1977
1978         if (chan->state != BT_CONNECTED)
1979                 return -ENOTCONN;
1980
1981         if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1982                 return 0;
1983
1984         if (__chan_is_moving(chan))
1985                 return 0;
1986
1987         while (chan->tx_send_head &&
1988                chan->unacked_frames < chan->remote_tx_win &&
1989                chan->tx_state == L2CAP_TX_STATE_XMIT) {
1990
1991                 skb = chan->tx_send_head;
1992
1993                 bt_cb(skb)->control.retries = 1;
1994                 control = &bt_cb(skb)->control;
1995
1996                 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1997                         control->final = 1;
1998
1999                 control->reqseq = chan->buffer_seq;
2000                 chan->last_acked_seq = chan->buffer_seq;
2001                 control->txseq = chan->next_tx_seq;
2002
2003                 __pack_control(chan, control, skb);
2004
2005                 if (chan->fcs == L2CAP_FCS_CRC16) {
2006                         u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2007                         put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2008                 }
2009
2010                 /* Clone after data has been modified. Data is assumed to be
2011                    read-only (for locking purposes) on cloned sk_buffs.
2012                  */
2013                 tx_skb = skb_clone(skb, GFP_KERNEL);
2014
2015                 if (!tx_skb)
2016                         break;
2017
2018                 __set_retrans_timer(chan);
2019
2020                 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2021                 chan->unacked_frames++;
2022                 chan->frames_sent++;
2023                 sent++;
2024
2025                 if (skb_queue_is_last(&chan->tx_q, skb))
2026                         chan->tx_send_head = NULL;
2027                 else
2028                         chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
2029
2030                 l2cap_do_send(chan, tx_skb);
2031                 BT_DBG("Sent txseq %u", control->txseq);
2032         }
2033
2034         BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
2035                chan->unacked_frames, skb_queue_len(&chan->tx_q));
2036
2037         return sent;
2038 }
2039
2040 static void l2cap_ertm_resend(struct l2cap_chan *chan)
2041 {
2042         struct l2cap_ctrl control;
2043         struct sk_buff *skb;
2044         struct sk_buff *tx_skb;
2045         u16 seq;
2046
2047         BT_DBG("chan %p", chan);
2048
2049         if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2050                 return;
2051
2052         if (__chan_is_moving(chan))
2053                 return;
2054
2055         while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
2056                 seq = l2cap_seq_list_pop(&chan->retrans_list);
2057
2058                 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
2059                 if (!skb) {
2060                         BT_DBG("Error: Can't retransmit seq %d, frame missing",
2061                                seq);
2062                         continue;
2063                 }
2064
2065                 bt_cb(skb)->control.retries++;
2066                 control = bt_cb(skb)->control;
2067
2068                 if (chan->max_tx != 0 &&
2069                     bt_cb(skb)->control.retries > chan->max_tx) {
2070                         BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2071                         l2cap_send_disconn_req(chan, ECONNRESET);
2072                         l2cap_seq_list_clear(&chan->retrans_list);
2073                         break;
2074                 }
2075
2076                 control.reqseq = chan->buffer_seq;
2077                 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2078                         control.final = 1;
2079                 else
2080                         control.final = 0;
2081
2082                 if (skb_cloned(skb)) {
2083                         /* Cloned sk_buffs are read-only, so we need a
2084                          * writeable copy
2085                          */
2086                         tx_skb = skb_copy(skb, GFP_KERNEL);
2087                 } else {
2088                         tx_skb = skb_clone(skb, GFP_KERNEL);
2089                 }
2090
2091                 if (!tx_skb) {
2092                         l2cap_seq_list_clear(&chan->retrans_list);
2093                         break;
2094                 }
2095
2096                 /* Update skb contents */
2097                 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2098                         put_unaligned_le32(__pack_extended_control(&control),
2099                                            tx_skb->data + L2CAP_HDR_SIZE);
2100                 } else {
2101                         put_unaligned_le16(__pack_enhanced_control(&control),
2102                                            tx_skb->data + L2CAP_HDR_SIZE);
2103                 }
2104
2105                 if (chan->fcs == L2CAP_FCS_CRC16) {
2106                         u16 fcs = crc16(0, (u8 *) tx_skb->data, tx_skb->len);
2107                         put_unaligned_le16(fcs, skb_put(tx_skb,
2108                                                         L2CAP_FCS_SIZE));
2109                 }
2110
2111                 l2cap_do_send(chan, tx_skb);
2112
2113                 BT_DBG("Resent txseq %d", control.txseq);
2114
2115                 chan->last_acked_seq = chan->buffer_seq;
2116         }
2117 }
2118
2119 static void l2cap_retransmit(struct l2cap_chan *chan,
2120                              struct l2cap_ctrl *control)
2121 {
2122         BT_DBG("chan %p, control %p", chan, control);
2123
2124         l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2125         l2cap_ertm_resend(chan);
2126 }
2127
2128 static void l2cap_retransmit_all(struct l2cap_chan *chan,
2129                                  struct l2cap_ctrl *control)
2130 {
2131         struct sk_buff *skb;
2132
2133         BT_DBG("chan %p, control %p", chan, control);
2134
2135         if (control->poll)
2136                 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2137
2138         l2cap_seq_list_clear(&chan->retrans_list);
2139
2140         if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2141                 return;
2142
2143         if (chan->unacked_frames) {
2144                 skb_queue_walk(&chan->tx_q, skb) {
2145                         if (bt_cb(skb)->control.txseq == control->reqseq ||
2146                             skb == chan->tx_send_head)
2147                                 break;
2148                 }
2149
2150                 skb_queue_walk_from(&chan->tx_q, skb) {
2151                         if (skb == chan->tx_send_head)
2152                                 break;
2153
2154                         l2cap_seq_list_append(&chan->retrans_list,
2155                                               bt_cb(skb)->control.txseq);
2156                 }
2157
2158                 l2cap_ertm_resend(chan);
2159         }
2160 }
2161
2162 static void l2cap_send_ack(struct l2cap_chan *chan)
2163 {
2164         struct l2cap_ctrl control;
2165         u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2166                                          chan->last_acked_seq);
2167         int threshold;
2168
2169         BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2170                chan, chan->last_acked_seq, chan->buffer_seq);
2171
2172         memset(&control, 0, sizeof(control));
2173         control.sframe = 1;
2174
2175         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2176             chan->rx_state == L2CAP_RX_STATE_RECV) {
2177                 __clear_ack_timer(chan);
2178                 control.super = L2CAP_SUPER_RNR;
2179                 control.reqseq = chan->buffer_seq;
2180                 l2cap_send_sframe(chan, &control);
2181         } else {
2182                 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2183                         l2cap_ertm_send(chan);
2184                         /* If any i-frames were sent, they included an ack */
2185                         if (chan->buffer_seq == chan->last_acked_seq)
2186                                 frames_to_ack = 0;
2187                 }
2188
2189                 /* Ack now if the window is 3/4ths full.
2190                  * Calculate without mul or div
2191                  */
2192                 threshold = chan->ack_win;
2193                 threshold += threshold << 1;
2194                 threshold >>= 2;
2195
2196                 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2197                        threshold);
2198
2199                 if (frames_to_ack >= threshold) {
2200                         __clear_ack_timer(chan);
2201                         control.super = L2CAP_SUPER_RR;
2202                         control.reqseq = chan->buffer_seq;
2203                         l2cap_send_sframe(chan, &control);
2204                         frames_to_ack = 0;
2205                 }
2206
2207                 if (frames_to_ack)
2208                         __set_ack_timer(chan);
2209         }
2210 }
2211
2212 static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2213                                          struct msghdr *msg, int len,
2214                                          int count, struct sk_buff *skb)
2215 {
2216         struct l2cap_conn *conn = chan->conn;
2217         struct sk_buff **frag;
2218         int sent = 0;
2219
2220         if (memcpy_fromiovec(skb_put(skb, count), msg->msg_iov, count))
2221                 return -EFAULT;
2222
2223         sent += count;
2224         len  -= count;
2225
2226         /* Continuation fragments (no L2CAP header) */
2227         frag = &skb_shinfo(skb)->frag_list;
2228         while (len) {
2229                 struct sk_buff *tmp;
2230
2231                 count = min_t(unsigned int, conn->mtu, len);
2232
2233                 tmp = chan->ops->alloc_skb(chan, count,
2234                                            msg->msg_flags & MSG_DONTWAIT);
2235                 if (IS_ERR(tmp))
2236                         return PTR_ERR(tmp);
2237
2238                 *frag = tmp;
2239
2240                 if (memcpy_fromiovec(skb_put(*frag, count), msg->msg_iov, count))
2241                         return -EFAULT;
2242
2243                 (*frag)->priority = skb->priority;
2244
2245                 sent += count;
2246                 len  -= count;
2247
2248                 skb->len += (*frag)->len;
2249                 skb->data_len += (*frag)->len;
2250
2251                 frag = &(*frag)->next;
2252         }
2253
2254         return sent;
2255 }
2256
2257 static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2258                                                  struct msghdr *msg, size_t len,
2259                                                  u32 priority)
2260 {
2261         struct l2cap_conn *conn = chan->conn;
2262         struct sk_buff *skb;
2263         int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2264         struct l2cap_hdr *lh;
2265
2266         BT_DBG("chan %p len %zu priority %u", chan, len, priority);
2267
2268         count = min_t(unsigned int, (conn->mtu - hlen), len);
2269
2270         skb = chan->ops->alloc_skb(chan, count + hlen,
2271                                    msg->msg_flags & MSG_DONTWAIT);
2272         if (IS_ERR(skb))
2273                 return skb;
2274
2275         skb->priority = priority;
2276
2277         /* Create L2CAP header */
2278         lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2279         lh->cid = cpu_to_le16(chan->dcid);
2280         lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2281         put_unaligned(chan->psm, skb_put(skb, L2CAP_PSMLEN_SIZE));
2282
2283         err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2284         if (unlikely(err < 0)) {
2285                 kfree_skb(skb);
2286                 return ERR_PTR(err);
2287         }
2288         return skb;
2289 }
2290
2291 static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2292                                               struct msghdr *msg, size_t len,
2293                                               u32 priority)
2294 {
2295         struct l2cap_conn *conn = chan->conn;
2296         struct sk_buff *skb;
2297         int err, count;
2298         struct l2cap_hdr *lh;
2299
2300         BT_DBG("chan %p len %zu", chan, len);
2301
2302         count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2303
2304         skb = chan->ops->alloc_skb(chan, count + L2CAP_HDR_SIZE,
2305                                    msg->msg_flags & MSG_DONTWAIT);
2306         if (IS_ERR(skb))
2307                 return skb;
2308
2309         skb->priority = priority;
2310
2311         /* Create L2CAP header */
2312         lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2313         lh->cid = cpu_to_le16(chan->dcid);
2314         lh->len = cpu_to_le16(len);
2315
2316         err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2317         if (unlikely(err < 0)) {
2318                 kfree_skb(skb);
2319                 return ERR_PTR(err);
2320         }
2321         return skb;
2322 }
2323
2324 static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2325                                                struct msghdr *msg, size_t len,
2326                                                u16 sdulen)
2327 {
2328         struct l2cap_conn *conn = chan->conn;
2329         struct sk_buff *skb;
2330         int err, count, hlen;
2331         struct l2cap_hdr *lh;
2332
2333         BT_DBG("chan %p len %zu", chan, len);
2334
2335         if (!conn)
2336                 return ERR_PTR(-ENOTCONN);
2337
2338         hlen = __ertm_hdr_size(chan);
2339
2340         if (sdulen)
2341                 hlen += L2CAP_SDULEN_SIZE;
2342
2343         if (chan->fcs == L2CAP_FCS_CRC16)
2344                 hlen += L2CAP_FCS_SIZE;
2345
2346         count = min_t(unsigned int, (conn->mtu - hlen), len);
2347
2348         skb = chan->ops->alloc_skb(chan, count + hlen,
2349                                    msg->msg_flags & MSG_DONTWAIT);
2350         if (IS_ERR(skb))
2351                 return skb;
2352
2353         /* Create L2CAP header */
2354         lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2355         lh->cid = cpu_to_le16(chan->dcid);
2356         lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2357
2358         /* Control header is populated later */
2359         if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2360                 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2361         else
2362                 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2363
2364         if (sdulen)
2365                 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2366
2367         err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2368         if (unlikely(err < 0)) {
2369                 kfree_skb(skb);
2370                 return ERR_PTR(err);
2371         }
2372
2373         bt_cb(skb)->control.fcs = chan->fcs;
2374         bt_cb(skb)->control.retries = 0;
2375         return skb;
2376 }
2377
2378 static int l2cap_segment_sdu(struct l2cap_chan *chan,
2379                              struct sk_buff_head *seg_queue,
2380                              struct msghdr *msg, size_t len)
2381 {
2382         struct sk_buff *skb;
2383         u16 sdu_len;
2384         size_t pdu_len;
2385         u8 sar;
2386
2387         BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2388
2389         /* It is critical that ERTM PDUs fit in a single HCI fragment,
2390          * so fragmented skbs are not used.  The HCI layer's handling
2391          * of fragmented skbs is not compatible with ERTM's queueing.
2392          */
2393
2394         /* PDU size is derived from the HCI MTU */
2395         pdu_len = chan->conn->mtu;
2396
2397         /* Constrain PDU size for BR/EDR connections */
2398         if (!chan->hs_hcon)
2399                 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2400
2401         /* Adjust for largest possible L2CAP overhead. */
2402         if (chan->fcs)
2403                 pdu_len -= L2CAP_FCS_SIZE;
2404
2405         pdu_len -= __ertm_hdr_size(chan);
2406
2407         /* Remote device may have requested smaller PDUs */
2408         pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2409
2410         if (len <= pdu_len) {
2411                 sar = L2CAP_SAR_UNSEGMENTED;
2412                 sdu_len = 0;
2413                 pdu_len = len;
2414         } else {
2415                 sar = L2CAP_SAR_START;
2416                 sdu_len = len;
2417                 pdu_len -= L2CAP_SDULEN_SIZE;
2418         }
2419
2420         while (len > 0) {
2421                 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2422
2423                 if (IS_ERR(skb)) {
2424                         __skb_queue_purge(seg_queue);
2425                         return PTR_ERR(skb);
2426                 }
2427
2428                 bt_cb(skb)->control.sar = sar;
2429                 __skb_queue_tail(seg_queue, skb);
2430
2431                 len -= pdu_len;
2432                 if (sdu_len) {
2433                         sdu_len = 0;
2434                         pdu_len += L2CAP_SDULEN_SIZE;
2435                 }
2436
2437                 if (len <= pdu_len) {
2438                         sar = L2CAP_SAR_END;
2439                         pdu_len = len;
2440                 } else {
2441                         sar = L2CAP_SAR_CONTINUE;
2442                 }
2443         }
2444
2445         return 0;
2446 }
2447
2448 int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len,
2449                     u32 priority)
2450 {
2451         struct sk_buff *skb;
2452         int err;
2453         struct sk_buff_head seg_queue;
2454
2455         if (!chan->conn)
2456                 return -ENOTCONN;
2457
2458         /* Connectionless channel */
2459         if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2460                 skb = l2cap_create_connless_pdu(chan, msg, len, priority);
2461                 if (IS_ERR(skb))
2462                         return PTR_ERR(skb);
2463
2464                 l2cap_do_send(chan, skb);
2465                 return len;
2466         }
2467
2468         switch (chan->mode) {
2469         case L2CAP_MODE_BASIC:
2470                 /* Check outgoing MTU */
2471                 if (len > chan->omtu)
2472                         return -EMSGSIZE;
2473
2474                 /* Create a basic PDU */
2475                 skb = l2cap_create_basic_pdu(chan, msg, len, priority);
2476                 if (IS_ERR(skb))
2477                         return PTR_ERR(skb);
2478
2479                 l2cap_do_send(chan, skb);
2480                 err = len;
2481                 break;
2482
2483         case L2CAP_MODE_ERTM:
2484         case L2CAP_MODE_STREAMING:
2485                 /* Check outgoing MTU */
2486                 if (len > chan->omtu) {
2487                         err = -EMSGSIZE;
2488                         break;
2489                 }
2490
2491                 __skb_queue_head_init(&seg_queue);
2492
2493                 /* Do segmentation before calling in to the state machine,
2494                  * since it's possible to block while waiting for memory
2495                  * allocation.
2496                  */
2497                 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2498
2499                 /* The channel could have been closed while segmenting,
2500                  * check that it is still connected.
2501                  */
2502                 if (chan->state != BT_CONNECTED) {
2503                         __skb_queue_purge(&seg_queue);
2504                         err = -ENOTCONN;
2505                 }
2506
2507                 if (err)
2508                         break;
2509
2510                 if (chan->mode == L2CAP_MODE_ERTM)
2511                         l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2512                 else
2513                         l2cap_streaming_send(chan, &seg_queue);
2514
2515                 err = len;
2516
2517                 /* If the skbs were not queued for sending, they'll still be in
2518                  * seg_queue and need to be purged.
2519                  */
2520                 __skb_queue_purge(&seg_queue);
2521                 break;
2522
2523         default:
2524                 BT_DBG("bad state %1.1x", chan->mode);
2525                 err = -EBADFD;
2526         }
2527
2528         return err;
2529 }
2530
2531 static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2532 {
2533         struct l2cap_ctrl control;
2534         u16 seq;
2535
2536         BT_DBG("chan %p, txseq %u", chan, txseq);
2537
2538         memset(&control, 0, sizeof(control));
2539         control.sframe = 1;
2540         control.super = L2CAP_SUPER_SREJ;
2541
2542         for (seq = chan->expected_tx_seq; seq != txseq;
2543              seq = __next_seq(chan, seq)) {
2544                 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2545                         control.reqseq = seq;
2546                         l2cap_send_sframe(chan, &control);
2547                         l2cap_seq_list_append(&chan->srej_list, seq);
2548                 }
2549         }
2550
2551         chan->expected_tx_seq = __next_seq(chan, txseq);
2552 }
2553
2554 static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2555 {
2556         struct l2cap_ctrl control;
2557
2558         BT_DBG("chan %p", chan);
2559
2560         if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2561                 return;
2562
2563         memset(&control, 0, sizeof(control));
2564         control.sframe = 1;
2565         control.super = L2CAP_SUPER_SREJ;
2566         control.reqseq = chan->srej_list.tail;
2567         l2cap_send_sframe(chan, &control);
2568 }
2569
2570 static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2571 {
2572         struct l2cap_ctrl control;
2573         u16 initial_head;
2574         u16 seq;
2575
2576         BT_DBG("chan %p, txseq %u", chan, txseq);
2577
2578         memset(&control, 0, sizeof(control));
2579         control.sframe = 1;
2580         control.super = L2CAP_SUPER_SREJ;
2581
2582         /* Capture initial list head to allow only one pass through the list. */
2583         initial_head = chan->srej_list.head;
2584
2585         do {
2586                 seq = l2cap_seq_list_pop(&chan->srej_list);
2587                 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2588                         break;
2589
2590                 control.reqseq = seq;
2591                 l2cap_send_sframe(chan, &control);
2592                 l2cap_seq_list_append(&chan->srej_list, seq);
2593         } while (chan->srej_list.head != initial_head);
2594 }
2595
2596 static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2597 {
2598         struct sk_buff *acked_skb;
2599         u16 ackseq;
2600
2601         BT_DBG("chan %p, reqseq %u", chan, reqseq);
2602
2603         if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2604                 return;
2605
2606         BT_DBG("expected_ack_seq %u, unacked_frames %u",
2607                chan->expected_ack_seq, chan->unacked_frames);
2608
2609         for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2610              ackseq = __next_seq(chan, ackseq)) {
2611
2612                 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2613                 if (acked_skb) {
2614                         skb_unlink(acked_skb, &chan->tx_q);
2615                         kfree_skb(acked_skb);
2616                         chan->unacked_frames--;
2617                 }
2618         }
2619
2620         chan->expected_ack_seq = reqseq;
2621
2622         if (chan->unacked_frames == 0)
2623                 __clear_retrans_timer(chan);
2624
2625         BT_DBG("unacked_frames %u", chan->unacked_frames);
2626 }
2627
2628 static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2629 {
2630         BT_DBG("chan %p", chan);
2631
2632         chan->expected_tx_seq = chan->buffer_seq;
2633         l2cap_seq_list_clear(&chan->srej_list);
2634         skb_queue_purge(&chan->srej_q);
2635         chan->rx_state = L2CAP_RX_STATE_RECV;
2636 }
2637
2638 static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2639                                 struct l2cap_ctrl *control,
2640                                 struct sk_buff_head *skbs, u8 event)
2641 {
2642         BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2643                event);
2644
2645         switch (event) {
2646         case L2CAP_EV_DATA_REQUEST:
2647                 if (chan->tx_send_head == NULL)
2648                         chan->tx_send_head = skb_peek(skbs);
2649
2650                 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2651                 l2cap_ertm_send(chan);
2652                 break;
2653         case L2CAP_EV_LOCAL_BUSY_DETECTED:
2654                 BT_DBG("Enter LOCAL_BUSY");
2655                 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2656
2657                 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2658                         /* The SREJ_SENT state must be aborted if we are to
2659                          * enter the LOCAL_BUSY state.
2660                          */
2661                         l2cap_abort_rx_srej_sent(chan);
2662                 }
2663
2664                 l2cap_send_ack(chan);
2665
2666                 break;
2667         case L2CAP_EV_LOCAL_BUSY_CLEAR:
2668                 BT_DBG("Exit LOCAL_BUSY");
2669                 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2670
2671                 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2672                         struct l2cap_ctrl local_control;
2673
2674                         memset(&local_control, 0, sizeof(local_control));
2675                         local_control.sframe = 1;
2676                         local_control.super = L2CAP_SUPER_RR;
2677                         local_control.poll = 1;
2678                         local_control.reqseq = chan->buffer_seq;
2679                         l2cap_send_sframe(chan, &local_control);
2680
2681                         chan->retry_count = 1;
2682                         __set_monitor_timer(chan);
2683                         chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2684                 }
2685                 break;
2686         case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2687                 l2cap_process_reqseq(chan, control->reqseq);
2688                 break;
2689         case L2CAP_EV_EXPLICIT_POLL:
2690                 l2cap_send_rr_or_rnr(chan, 1);
2691                 chan->retry_count = 1;
2692                 __set_monitor_timer(chan);
2693                 __clear_ack_timer(chan);
2694                 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2695                 break;
2696         case L2CAP_EV_RETRANS_TO:
2697                 l2cap_send_rr_or_rnr(chan, 1);
2698                 chan->retry_count = 1;
2699                 __set_monitor_timer(chan);
2700                 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2701                 break;
2702         case L2CAP_EV_RECV_FBIT:
2703                 /* Nothing to process */
2704                 break;
2705         default:
2706                 break;
2707         }
2708 }
2709
2710 static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2711                                   struct l2cap_ctrl *control,
2712                                   struct sk_buff_head *skbs, u8 event)
2713 {
2714         BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2715                event);
2716
2717         switch (event) {
2718         case L2CAP_EV_DATA_REQUEST:
2719                 if (chan->tx_send_head == NULL)
2720                         chan->tx_send_head = skb_peek(skbs);
2721                 /* Queue data, but don't send. */
2722                 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2723                 break;
2724         case L2CAP_EV_LOCAL_BUSY_DETECTED:
2725                 BT_DBG("Enter LOCAL_BUSY");
2726                 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2727
2728                 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2729                         /* The SREJ_SENT state must be aborted if we are to
2730                          * enter the LOCAL_BUSY state.
2731                          */
2732                         l2cap_abort_rx_srej_sent(chan);
2733                 }
2734
2735                 l2cap_send_ack(chan);
2736
2737                 break;
2738         case L2CAP_EV_LOCAL_BUSY_CLEAR:
2739                 BT_DBG("Exit LOCAL_BUSY");
2740                 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2741
2742                 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2743                         struct l2cap_ctrl local_control;
2744                         memset(&local_control, 0, sizeof(local_control));
2745                         local_control.sframe = 1;
2746                         local_control.super = L2CAP_SUPER_RR;
2747                         local_control.poll = 1;
2748                         local_control.reqseq = chan->buffer_seq;
2749                         l2cap_send_sframe(chan, &local_control);
2750
2751                         chan->retry_count = 1;
2752                         __set_monitor_timer(chan);
2753                         chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2754                 }
2755                 break;
2756         case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2757                 l2cap_process_reqseq(chan, control->reqseq);
2758
2759                 /* Fall through */
2760
2761         case L2CAP_EV_RECV_FBIT:
2762                 if (control && control->final) {
2763                         __clear_monitor_timer(chan);
2764                         if (chan->unacked_frames > 0)
2765                                 __set_retrans_timer(chan);
2766                         chan->retry_count = 0;
2767                         chan->tx_state = L2CAP_TX_STATE_XMIT;
2768                         BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2769                 }
2770                 break;
2771         case L2CAP_EV_EXPLICIT_POLL:
2772                 /* Ignore */
2773                 break;
2774         case L2CAP_EV_MONITOR_TO:
2775                 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2776                         l2cap_send_rr_or_rnr(chan, 1);
2777                         __set_monitor_timer(chan);
2778                         chan->retry_count++;
2779                 } else {
2780                         l2cap_send_disconn_req(chan, ECONNABORTED);
2781                 }
2782                 break;
2783         default:
2784                 break;
2785         }
2786 }
2787
2788 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2789                      struct sk_buff_head *skbs, u8 event)
2790 {
2791         BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2792                chan, control, skbs, event, chan->tx_state);
2793
2794         switch (chan->tx_state) {
2795         case L2CAP_TX_STATE_XMIT:
2796                 l2cap_tx_state_xmit(chan, control, skbs, event);
2797                 break;
2798         case L2CAP_TX_STATE_WAIT_F:
2799                 l2cap_tx_state_wait_f(chan, control, skbs, event);
2800                 break;
2801         default:
2802                 /* Ignore event */
2803                 break;
2804         }
2805 }
2806
2807 static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2808                              struct l2cap_ctrl *control)
2809 {
2810         BT_DBG("chan %p, control %p", chan, control);
2811         l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2812 }
2813
2814 static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2815                                   struct l2cap_ctrl *control)
2816 {
2817         BT_DBG("chan %p, control %p", chan, control);
2818         l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2819 }
2820
2821 /* Copy frame to all raw sockets on that connection */
2822 static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2823 {
2824         struct sk_buff *nskb;
2825         struct l2cap_chan *chan;
2826
2827         BT_DBG("conn %p", conn);
2828
2829         mutex_lock(&conn->chan_lock);
2830
2831         list_for_each_entry(chan, &conn->chan_l, list) {
2832                 struct sock *sk = chan->sk;
2833                 if (chan->chan_type != L2CAP_CHAN_RAW)
2834                         continue;
2835
2836                 /* Don't send frame to the socket it came from */
2837                 if (skb->sk == sk)
2838                         continue;
2839                 nskb = skb_clone(skb, GFP_KERNEL);
2840                 if (!nskb)
2841                         continue;
2842
2843                 if (chan->ops->recv(chan, nskb))
2844                         kfree_skb(nskb);
2845         }
2846
2847         mutex_unlock(&conn->chan_lock);
2848 }
2849
2850 /* ---- L2CAP signalling commands ---- */
2851 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2852                                        u8 ident, u16 dlen, void *data)
2853 {
2854         struct sk_buff *skb, **frag;
2855         struct l2cap_cmd_hdr *cmd;
2856         struct l2cap_hdr *lh;
2857         int len, count;
2858
2859         BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2860                conn, code, ident, dlen);
2861
2862         if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2863                 return NULL;
2864
2865         len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2866         count = min_t(unsigned int, conn->mtu, len);
2867
2868         skb = bt_skb_alloc(count, GFP_KERNEL);
2869         if (!skb)
2870                 return NULL;
2871
2872         lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2873         lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2874
2875         if (conn->hcon->type == LE_LINK)
2876                 lh->cid = __constant_cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2877         else
2878                 lh->cid = __constant_cpu_to_le16(L2CAP_CID_SIGNALING);
2879
2880         cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2881         cmd->code  = code;
2882         cmd->ident = ident;
2883         cmd->len   = cpu_to_le16(dlen);
2884
2885         if (dlen) {
2886                 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2887                 memcpy(skb_put(skb, count), data, count);
2888                 data += count;
2889         }
2890
2891         len -= skb->len;
2892
2893         /* Continuation fragments (no L2CAP header) */
2894         frag = &skb_shinfo(skb)->frag_list;
2895         while (len) {
2896                 count = min_t(unsigned int, conn->mtu, len);
2897
2898                 *frag = bt_skb_alloc(count, GFP_KERNEL);
2899                 if (!*frag)
2900                         goto fail;
2901
2902                 memcpy(skb_put(*frag, count), data, count);
2903
2904                 len  -= count;
2905                 data += count;
2906
2907                 frag = &(*frag)->next;
2908         }
2909
2910         return skb;
2911
2912 fail:
2913         kfree_skb(skb);
2914         return NULL;
2915 }
2916
2917 static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2918                                      unsigned long *val)
2919 {
2920         struct l2cap_conf_opt *opt = *ptr;
2921         int len;
2922
2923         len = L2CAP_CONF_OPT_SIZE + opt->len;
2924         *ptr += len;
2925
2926         *type = opt->type;
2927         *olen = opt->len;
2928
2929         switch (opt->len) {
2930         case 1:
2931                 *val = *((u8 *) opt->val);
2932                 break;
2933
2934         case 2:
2935                 *val = get_unaligned_le16(opt->val);
2936                 break;
2937
2938         case 4:
2939                 *val = get_unaligned_le32(opt->val);
2940                 break;
2941
2942         default:
2943                 *val = (unsigned long) opt->val;
2944                 break;
2945         }
2946
2947         BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2948         return len;
2949 }
2950
2951 static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2952 {
2953         struct l2cap_conf_opt *opt = *ptr;
2954
2955         BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2956
2957         opt->type = type;
2958         opt->len  = len;
2959
2960         switch (len) {
2961         case 1:
2962                 *((u8 *) opt->val)  = val;
2963                 break;
2964
2965         case 2:
2966                 put_unaligned_le16(val, opt->val);
2967                 break;
2968
2969         case 4:
2970                 put_unaligned_le32(val, opt->val);
2971                 break;
2972
2973         default:
2974                 memcpy(opt->val, (void *) val, len);
2975                 break;
2976         }
2977
2978         *ptr += L2CAP_CONF_OPT_SIZE + len;
2979 }
2980
2981 static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
2982 {
2983         struct l2cap_conf_efs efs;
2984
2985         switch (chan->mode) {
2986         case L2CAP_MODE_ERTM:
2987                 efs.id          = chan->local_id;
2988                 efs.stype       = chan->local_stype;
2989                 efs.msdu        = cpu_to_le16(chan->local_msdu);
2990                 efs.sdu_itime   = cpu_to_le32(chan->local_sdu_itime);
2991                 efs.acc_lat     = __constant_cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
2992                 efs.flush_to    = __constant_cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
2993                 break;
2994
2995         case L2CAP_MODE_STREAMING:
2996                 efs.id          = 1;
2997                 efs.stype       = L2CAP_SERV_BESTEFFORT;
2998                 efs.msdu        = cpu_to_le16(chan->local_msdu);
2999                 efs.sdu_itime   = cpu_to_le32(chan->local_sdu_itime);
3000                 efs.acc_lat     = 0;
3001                 efs.flush_to    = 0;
3002                 break;
3003
3004         default:
3005                 return;
3006         }
3007
3008         l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3009                            (unsigned long) &efs);
3010 }
3011
3012 static void l2cap_ack_timeout(struct work_struct *work)
3013 {
3014         struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3015                                                ack_timer.work);
3016         u16 frames_to_ack;
3017
3018         BT_DBG("chan %p", chan);
3019
3020         l2cap_chan_lock(chan);
3021
3022         frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3023                                      chan->last_acked_seq);
3024
3025         if (frames_to_ack)
3026                 l2cap_send_rr_or_rnr(chan, 0);
3027
3028         l2cap_chan_unlock(chan);
3029         l2cap_chan_put(chan);
3030 }
3031
3032 int l2cap_ertm_init(struct l2cap_chan *chan)
3033 {
3034         int err;
3035
3036         chan->next_tx_seq = 0;
3037         chan->expected_tx_seq = 0;
3038         chan->expected_ack_seq = 0;
3039         chan->unacked_frames = 0;
3040         chan->buffer_seq = 0;
3041         chan->frames_sent = 0;
3042         chan->last_acked_seq = 0;
3043         chan->sdu = NULL;
3044         chan->sdu_last_frag = NULL;
3045         chan->sdu_len = 0;
3046
3047         skb_queue_head_init(&chan->tx_q);
3048
3049         chan->local_amp_id = 0;
3050         chan->move_id = 0;
3051         chan->move_state = L2CAP_MOVE_STABLE;
3052         chan->move_role = L2CAP_MOVE_ROLE_NONE;
3053
3054         if (chan->mode != L2CAP_MODE_ERTM)
3055                 return 0;
3056
3057         chan->rx_state = L2CAP_RX_STATE_RECV;
3058         chan->tx_state = L2CAP_TX_STATE_XMIT;
3059
3060         INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3061         INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3062         INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3063
3064         skb_queue_head_init(&chan->srej_q);
3065
3066         err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3067         if (err < 0)
3068                 return err;
3069
3070         err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3071         if (err < 0)
3072                 l2cap_seq_list_free(&chan->srej_list);
3073
3074         return err;
3075 }
3076
3077 static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3078 {
3079         switch (mode) {
3080         case L2CAP_MODE_STREAMING:
3081         case L2CAP_MODE_ERTM:
3082                 if (l2cap_mode_supported(mode, remote_feat_mask))
3083                         return mode;
3084                 /* fall through */
3085         default:
3086                 return L2CAP_MODE_BASIC;
3087         }
3088 }
3089
3090 static inline bool __l2cap_ews_supported(struct l2cap_chan *chan)
3091 {
3092         return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_WINDOW;
3093 }
3094
3095 static inline bool __l2cap_efs_supported(struct l2cap_chan *chan)
3096 {
3097         return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_FLOW;
3098 }
3099
3100 static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3101                                       struct l2cap_conf_rfc *rfc)
3102 {
3103         if (chan->local_amp_id && chan->hs_hcon) {
3104                 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3105
3106                 /* Class 1 devices have must have ERTM timeouts
3107                  * exceeding the Link Supervision Timeout.  The
3108                  * default Link Supervision Timeout for AMP
3109                  * controllers is 10 seconds.
3110                  *
3111                  * Class 1 devices use 0xffffffff for their
3112                  * best-effort flush timeout, so the clamping logic
3113                  * will result in a timeout that meets the above
3114                  * requirement.  ERTM timeouts are 16-bit values, so
3115                  * the maximum timeout is 65.535 seconds.
3116                  */
3117
3118                 /* Convert timeout to milliseconds and round */
3119                 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3120
3121                 /* This is the recommended formula for class 2 devices
3122                  * that start ERTM timers when packets are sent to the
3123                  * controller.
3124                  */
3125                 ertm_to = 3 * ertm_to + 500;
3126
3127                 if (ertm_to > 0xffff)
3128                         ertm_to = 0xffff;
3129
3130                 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3131                 rfc->monitor_timeout = rfc->retrans_timeout;
3132         } else {
3133                 rfc->retrans_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3134                 rfc->monitor_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3135         }
3136 }
3137
3138 static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3139 {
3140         if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3141             __l2cap_ews_supported(chan)) {
3142                 /* use extended control field */
3143                 set_bit(FLAG_EXT_CTRL, &chan->flags);
3144                 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3145         } else {
3146                 chan->tx_win = min_t(u16, chan->tx_win,
3147                                      L2CAP_DEFAULT_TX_WINDOW);
3148                 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3149         }
3150         chan->ack_win = chan->tx_win;
3151 }
3152
3153 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
3154 {
3155         struct l2cap_conf_req *req = data;
3156         struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3157         void *ptr = req->data;
3158         u16 size;
3159
3160         BT_DBG("chan %p", chan);
3161
3162         if (chan->num_conf_req || chan->num_conf_rsp)
3163                 goto done;
3164
3165         switch (chan->mode) {
3166         case L2CAP_MODE_STREAMING:
3167         case L2CAP_MODE_ERTM:
3168                 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3169                         break;
3170
3171                 if (__l2cap_efs_supported(chan))
3172                         set_bit(FLAG_EFS_ENABLE, &chan->flags);
3173
3174                 /* fall through */
3175         default:
3176                 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3177                 break;
3178         }
3179
3180 done:
3181         if (chan->imtu != L2CAP_DEFAULT_MTU)
3182                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3183
3184         switch (chan->mode) {
3185         case L2CAP_MODE_BASIC:
3186                 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3187                     !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3188                         break;
3189
3190                 rfc.mode            = L2CAP_MODE_BASIC;
3191                 rfc.txwin_size      = 0;
3192                 rfc.max_transmit    = 0;
3193                 rfc.retrans_timeout = 0;
3194                 rfc.monitor_timeout = 0;
3195                 rfc.max_pdu_size    = 0;
3196
3197                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3198                                    (unsigned long) &rfc);
3199                 break;
3200
3201         case L2CAP_MODE_ERTM:
3202                 rfc.mode            = L2CAP_MODE_ERTM;
3203                 rfc.max_transmit    = chan->max_tx;
3204
3205                 __l2cap_set_ertm_timeouts(chan, &rfc);
3206
3207                 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3208                              L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3209                              L2CAP_FCS_SIZE);
3210                 rfc.max_pdu_size = cpu_to_le16(size);
3211
3212                 l2cap_txwin_setup(chan);
3213
3214                 rfc.txwin_size = min_t(u16, chan->tx_win,
3215                                        L2CAP_DEFAULT_TX_WINDOW);
3216
3217                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3218                                    (unsigned long) &rfc);
3219
3220                 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3221                         l2cap_add_opt_efs(&ptr, chan);
3222
3223                 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3224                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3225                                            chan->tx_win);
3226
3227                 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3228                         if (chan->fcs == L2CAP_FCS_NONE ||
3229                             test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3230                                 chan->fcs = L2CAP_FCS_NONE;
3231                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3232                                                    chan->fcs);
3233                         }
3234                 break;
3235
3236         case L2CAP_MODE_STREAMING:
3237                 l2cap_txwin_setup(chan);
3238                 rfc.mode            = L2CAP_MODE_STREAMING;
3239                 rfc.txwin_size      = 0;
3240                 rfc.max_transmit    = 0;
3241                 rfc.retrans_timeout = 0;
3242                 rfc.monitor_timeout = 0;
3243
3244                 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3245                              L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3246                              L2CAP_FCS_SIZE);
3247                 rfc.max_pdu_size = cpu_to_le16(size);
3248
3249                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3250                                    (unsigned long) &rfc);
3251
3252                 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3253                         l2cap_add_opt_efs(&ptr, chan);
3254
3255                 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3256                         if (chan->fcs == L2CAP_FCS_NONE ||
3257                             test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3258                                 chan->fcs = L2CAP_FCS_NONE;
3259                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3260                                                    chan->fcs);
3261                         }
3262                 break;
3263         }
3264
3265         req->dcid  = cpu_to_le16(chan->dcid);
3266         req->flags = __constant_cpu_to_le16(0);
3267
3268         return ptr - data;
3269 }
3270
3271 static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3272 {
3273         struct l2cap_conf_rsp *rsp = data;
3274         void *ptr = rsp->data;
3275         void *req = chan->conf_req;
3276         int len = chan->conf_len;
3277         int type, hint, olen;
3278         unsigned long val;
3279         struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3280         struct l2cap_conf_efs efs;
3281         u8 remote_efs = 0;
3282         u16 mtu = L2CAP_DEFAULT_MTU;
3283         u16 result = L2CAP_CONF_SUCCESS;
3284         u16 size;
3285
3286         BT_DBG("chan %p", chan);
3287
3288         while (len >= L2CAP_CONF_OPT_SIZE) {
3289                 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3290
3291                 hint  = type & L2CAP_CONF_HINT;
3292                 type &= L2CAP_CONF_MASK;
3293
3294                 switch (type) {
3295                 case L2CAP_CONF_MTU:
3296                         mtu = val;
3297                         break;
3298
3299                 case L2CAP_CONF_FLUSH_TO:
3300                         chan->flush_to = val;
3301                         break;
3302
3303                 case L2CAP_CONF_QOS:
3304                         break;
3305
3306                 case L2CAP_CONF_RFC:
3307                         if (olen == sizeof(rfc))
3308                                 memcpy(&rfc, (void *) val, olen);
3309                         break;
3310
3311                 case L2CAP_CONF_FCS:
3312                         if (val == L2CAP_FCS_NONE)
3313                                 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3314                         break;
3315
3316                 case L2CAP_CONF_EFS:
3317                         remote_efs = 1;
3318                         if (olen == sizeof(efs))
3319                                 memcpy(&efs, (void *) val, olen);
3320                         break;
3321
3322                 case L2CAP_CONF_EWS:
3323                         if (!enable_hs)
3324                                 return -ECONNREFUSED;
3325
3326                         set_bit(FLAG_EXT_CTRL, &chan->flags);
3327                         set_bit(CONF_EWS_RECV, &chan->conf_state);
3328                         chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3329                         chan->remote_tx_win = val;
3330                         break;
3331
3332                 default:
3333                         if (hint)
3334                                 break;
3335
3336                         result = L2CAP_CONF_UNKNOWN;
3337                         *((u8 *) ptr++) = type;
3338                         break;
3339                 }
3340         }
3341
3342         if (chan->num_conf_rsp || chan->num_conf_req > 1)
3343                 goto done;
3344
3345         switch (chan->mode) {
3346         case L2CAP_MODE_STREAMING:
3347         case L2CAP_MODE_ERTM:
3348                 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3349                         chan->mode = l2cap_select_mode(rfc.mode,
3350                                                        chan->conn->feat_mask);
3351                         break;
3352                 }
3353
3354                 if (remote_efs) {
3355                         if (__l2cap_efs_supported(chan))
3356                                 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3357                         else
3358                                 return -ECONNREFUSED;
3359                 }
3360
3361                 if (chan->mode != rfc.mode)
3362                         return -ECONNREFUSED;
3363
3364                 break;
3365         }
3366
3367 done:
3368         if (chan->mode != rfc.mode) {
3369                 result = L2CAP_CONF_UNACCEPT;
3370                 rfc.mode = chan->mode;
3371
3372                 if (chan->num_conf_rsp == 1)
3373                         return -ECONNREFUSED;
3374
3375                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3376                                    (unsigned long) &rfc);
3377         }
3378
3379         if (result == L2CAP_CONF_SUCCESS) {
3380                 /* Configure output options and let the other side know
3381                  * which ones we don't like. */
3382
3383                 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3384                         result = L2CAP_CONF_UNACCEPT;
3385                 else {
3386                         chan->omtu = mtu;
3387                         set_bit(CONF_MTU_DONE, &chan->conf_state);
3388                 }
3389                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3390
3391                 if (remote_efs) {
3392                         if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3393                             efs.stype != L2CAP_SERV_NOTRAFIC &&
3394                             efs.stype != chan->local_stype) {
3395
3396                                 result = L2CAP_CONF_UNACCEPT;
3397
3398                                 if (chan->num_conf_req >= 1)
3399                                         return -ECONNREFUSED;
3400
3401                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3402                                                    sizeof(efs),
3403                                                    (unsigned long) &efs);
3404                         } else {
3405                                 /* Send PENDING Conf Rsp */
3406                                 result = L2CAP_CONF_PENDING;
3407                                 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3408                         }
3409                 }
3410
3411                 switch (rfc.mode) {
3412                 case L2CAP_MODE_BASIC:
3413                         chan->fcs = L2CAP_FCS_NONE;
3414                         set_bit(CONF_MODE_DONE, &chan->conf_state);
3415                         break;
3416
3417                 case L2CAP_MODE_ERTM:
3418                         if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3419                                 chan->remote_tx_win = rfc.txwin_size;
3420                         else
3421                                 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3422
3423                         chan->remote_max_tx = rfc.max_transmit;
3424
3425                         size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3426                                      chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3427                                      L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3428                         rfc.max_pdu_size = cpu_to_le16(size);
3429                         chan->remote_mps = size;
3430
3431                         __l2cap_set_ertm_timeouts(chan, &rfc);
3432
3433                         set_bit(CONF_MODE_DONE, &chan->conf_state);
3434
3435                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3436                                            sizeof(rfc), (unsigned long) &rfc);
3437
3438                         if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3439                                 chan->remote_id = efs.id;
3440                                 chan->remote_stype = efs.stype;
3441                                 chan->remote_msdu = le16_to_cpu(efs.msdu);
3442                                 chan->remote_flush_to =
3443                                         le32_to_cpu(efs.flush_to);
3444                                 chan->remote_acc_lat =
3445                                         le32_to_cpu(efs.acc_lat);
3446                                 chan->remote_sdu_itime =
3447                                         le32_to_cpu(efs.sdu_itime);
3448                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3449                                                    sizeof(efs),
3450                                                    (unsigned long) &efs);
3451                         }
3452                         break;
3453
3454                 case L2CAP_MODE_STREAMING:
3455                         size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3456                                      chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3457                                      L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3458                         rfc.max_pdu_size = cpu_to_le16(size);
3459                         chan->remote_mps = size;
3460
3461                         set_bit(CONF_MODE_DONE, &chan->conf_state);
3462
3463                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3464                                            (unsigned long) &rfc);
3465
3466                         break;
3467
3468                 default:
3469                         result = L2CAP_CONF_UNACCEPT;
3470
3471                         memset(&rfc, 0, sizeof(rfc));
3472                         rfc.mode = chan->mode;
3473                 }
3474
3475                 if (result == L2CAP_CONF_SUCCESS)
3476                         set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3477         }
3478         rsp->scid   = cpu_to_le16(chan->dcid);
3479         rsp->result = cpu_to_le16(result);
3480         rsp->flags  = __constant_cpu_to_le16(0);
3481
3482         return ptr - data;
3483 }
3484
3485 static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3486                                 void *data, u16 *result)
3487 {
3488         struct l2cap_conf_req *req = data;
3489         void *ptr = req->data;
3490         int type, olen;
3491         unsigned long val;
3492         struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3493         struct l2cap_conf_efs efs;
3494
3495         BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3496
3497         while (len >= L2CAP_CONF_OPT_SIZE) {
3498                 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3499
3500                 switch (type) {
3501                 case L2CAP_CONF_MTU:
3502                         if (val < L2CAP_DEFAULT_MIN_MTU) {
3503                                 *result = L2CAP_CONF_UNACCEPT;
3504                                 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3505                         } else
3506                                 chan->imtu = val;
3507                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3508                         break;
3509
3510                 case L2CAP_CONF_FLUSH_TO:
3511                         chan->flush_to = val;
3512                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3513                                            2, chan->flush_to);
3514                         break;
3515
3516                 case L2CAP_CONF_RFC:
3517                         if (olen == sizeof(rfc))
3518                                 memcpy(&rfc, (void *)val, olen);
3519
3520                         if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3521                             rfc.mode != chan->mode)
3522                                 return -ECONNREFUSED;
3523
3524                         chan->fcs = 0;
3525
3526                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3527                                            sizeof(rfc), (unsigned long) &rfc);
3528                         break;
3529
3530                 case L2CAP_CONF_EWS:
3531                         chan->ack_win = min_t(u16, val, chan->ack_win);
3532                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3533                                            chan->tx_win);
3534                         break;
3535
3536                 case L2CAP_CONF_EFS:
3537                         if (olen == sizeof(efs))
3538                                 memcpy(&efs, (void *)val, olen);
3539
3540                         if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3541                             efs.stype != L2CAP_SERV_NOTRAFIC &&
3542                             efs.stype != chan->local_stype)
3543                                 return -ECONNREFUSED;
3544
3545                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3546                                            (unsigned long) &efs);
3547                         break;
3548
3549                 case L2CAP_CONF_FCS:
3550                         if (*result == L2CAP_CONF_PENDING)
3551                                 if (val == L2CAP_FCS_NONE)
3552                                         set_bit(CONF_RECV_NO_FCS,
3553                                                 &chan->conf_state);
3554                         break;
3555                 }
3556         }
3557
3558         if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3559                 return -ECONNREFUSED;
3560
3561         chan->mode = rfc.mode;
3562
3563         if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3564                 switch (rfc.mode) {
3565                 case L2CAP_MODE_ERTM:
3566                         chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3567                         chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3568                         chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3569                         if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3570                                 chan->ack_win = min_t(u16, chan->ack_win,
3571                                                       rfc.txwin_size);
3572
3573                         if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3574                                 chan->local_msdu = le16_to_cpu(efs.msdu);
3575                                 chan->local_sdu_itime =
3576                                         le32_to_cpu(efs.sdu_itime);
3577                                 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3578                                 chan->local_flush_to =
3579                                         le32_to_cpu(efs.flush_to);
3580                         }
3581                         break;
3582
3583                 case L2CAP_MODE_STREAMING:
3584                         chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3585                 }
3586         }
3587
3588         req->dcid   = cpu_to_le16(chan->dcid);
3589         req->flags  = __constant_cpu_to_le16(0);
3590
3591         return ptr - data;
3592 }
3593
3594 static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3595                                 u16 result, u16 flags)
3596 {
3597         struct l2cap_conf_rsp *rsp = data;
3598         void *ptr = rsp->data;
3599
3600         BT_DBG("chan %p", chan);
3601
3602         rsp->scid   = cpu_to_le16(chan->dcid);
3603         rsp->result = cpu_to_le16(result);
3604         rsp->flags  = cpu_to_le16(flags);
3605
3606         return ptr - data;
3607 }
3608
3609 void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3610 {
3611         struct l2cap_conn_rsp rsp;
3612         struct l2cap_conn *conn = chan->conn;
3613         u8 buf[128];
3614         u8 rsp_code;
3615
3616         rsp.scid   = cpu_to_le16(chan->dcid);
3617         rsp.dcid   = cpu_to_le16(chan->scid);
3618         rsp.result = __constant_cpu_to_le16(L2CAP_CR_SUCCESS);
3619         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
3620
3621         if (chan->hs_hcon)
3622                 rsp_code = L2CAP_CREATE_CHAN_RSP;
3623         else
3624                 rsp_code = L2CAP_CONN_RSP;
3625
3626         BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3627
3628         l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3629
3630         if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3631                 return;
3632
3633         l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3634                        l2cap_build_conf_req(chan, buf), buf);
3635         chan->num_conf_req++;
3636 }
3637
3638 static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3639 {
3640         int type, olen;
3641         unsigned long val;
3642         /* Use sane default values in case a misbehaving remote device
3643          * did not send an RFC or extended window size option.
3644          */
3645         u16 txwin_ext = chan->ack_win;
3646         struct l2cap_conf_rfc rfc = {
3647                 .mode = chan->mode,
3648                 .retrans_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3649                 .monitor_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3650                 .max_pdu_size = cpu_to_le16(chan->imtu),
3651                 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3652         };
3653
3654         BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3655
3656         if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3657                 return;
3658
3659         while (len >= L2CAP_CONF_OPT_SIZE) {
3660                 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3661
3662                 switch (type) {
3663                 case L2CAP_CONF_RFC:
3664                         if (olen == sizeof(rfc))
3665                                 memcpy(&rfc, (void *)val, olen);
3666                         break;
3667                 case L2CAP_CONF_EWS:
3668                         txwin_ext = val;
3669                         break;
3670                 }
3671         }
3672
3673         switch (rfc.mode) {
3674         case L2CAP_MODE_ERTM:
3675                 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3676                 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3677                 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3678                 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3679                         chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3680                 else
3681                         chan->ack_win = min_t(u16, chan->ack_win,
3682                                               rfc.txwin_size);
3683                 break;
3684         case L2CAP_MODE_STREAMING:
3685                 chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3686         }
3687 }
3688
3689 static inline int l2cap_command_rej(struct l2cap_conn *conn,
3690                                     struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3691                                     u8 *data)
3692 {
3693         struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3694
3695         if (cmd_len < sizeof(*rej))
3696                 return -EPROTO;
3697
3698         if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3699                 return 0;
3700
3701         if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3702             cmd->ident == conn->info_ident) {
3703                 cancel_delayed_work(&conn->info_timer);
3704
3705                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3706                 conn->info_ident = 0;
3707
3708                 l2cap_conn_start(conn);
3709         }
3710
3711         return 0;
3712 }
3713
3714 static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3715                                         struct l2cap_cmd_hdr *cmd,
3716                                         u8 *data, u8 rsp_code, u8 amp_id)
3717 {
3718         struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3719         struct l2cap_conn_rsp rsp;
3720         struct l2cap_chan *chan = NULL, *pchan;
3721         struct sock *parent, *sk = NULL;
3722         int result, status = L2CAP_CS_NO_INFO;
3723
3724         u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3725         __le16 psm = req->psm;
3726
3727         BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3728
3729         /* Check if we have socket listening on psm */
3730         pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, conn->src, conn->dst);
3731         if (!pchan) {
3732                 result = L2CAP_CR_BAD_PSM;
3733                 goto sendresp;
3734         }
3735
3736         parent = pchan->sk;
3737
3738         mutex_lock(&conn->chan_lock);
3739         lock_sock(parent);
3740
3741         /* Check if the ACL is secure enough (if not SDP) */
3742         if (psm != __constant_cpu_to_le16(L2CAP_PSM_SDP) &&
3743             !hci_conn_check_link_mode(conn->hcon)) {
3744                 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3745                 result = L2CAP_CR_SEC_BLOCK;
3746                 goto response;
3747         }
3748
3749         result = L2CAP_CR_NO_MEM;
3750
3751         /* Check if we already have channel with that dcid */
3752         if (__l2cap_get_chan_by_dcid(conn, scid))
3753                 goto response;
3754
3755         chan = pchan->ops->new_connection(pchan);
3756         if (!chan)
3757                 goto response;
3758
3759         sk = chan->sk;
3760
3761         /* For certain devices (ex: HID mouse), support for authentication,
3762          * pairing and bonding is optional. For such devices, inorder to avoid
3763          * the ACL alive for too long after L2CAP disconnection, reset the ACL
3764          * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3765          */
3766         conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3767
3768         bacpy(&bt_sk(sk)->src, conn->src);
3769         bacpy(&bt_sk(sk)->dst, conn->dst);
3770         chan->psm  = psm;
3771         chan->dcid = scid;
3772         chan->local_amp_id = amp_id;
3773
3774         __l2cap_chan_add(conn, chan);
3775
3776         dcid = chan->scid;
3777
3778         __set_chan_timer(chan, sk->sk_sndtimeo);
3779
3780         chan->ident = cmd->ident;
3781
3782         if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3783                 if (l2cap_chan_check_security(chan)) {
3784                         if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
3785                                 __l2cap_state_change(chan, BT_CONNECT2);
3786                                 result = L2CAP_CR_PEND;
3787                                 status = L2CAP_CS_AUTHOR_PEND;
3788                                 chan->ops->defer(chan);
3789                         } else {
3790                                 /* Force pending result for AMP controllers.
3791                                  * The connection will succeed after the
3792                                  * physical link is up.
3793                                  */
3794                                 if (amp_id) {
3795                                         __l2cap_state_change(chan, BT_CONNECT2);
3796                                         result = L2CAP_CR_PEND;
3797                                 } else {
3798                                         __l2cap_state_change(chan, BT_CONFIG);
3799                                         result = L2CAP_CR_SUCCESS;
3800                                 }
3801                                 status = L2CAP_CS_NO_INFO;
3802                         }
3803                 } else {
3804                         __l2cap_state_change(chan, BT_CONNECT2);
3805                         result = L2CAP_CR_PEND;
3806                         status = L2CAP_CS_AUTHEN_PEND;
3807                 }
3808         } else {
3809                 __l2cap_state_change(chan, BT_CONNECT2);
3810                 result = L2CAP_CR_PEND;
3811                 status = L2CAP_CS_NO_INFO;
3812         }
3813
3814 response:
3815         release_sock(parent);
3816         mutex_unlock(&conn->chan_lock);
3817
3818 sendresp:
3819         rsp.scid   = cpu_to_le16(scid);
3820         rsp.dcid   = cpu_to_le16(dcid);
3821         rsp.result = cpu_to_le16(result);
3822         rsp.status = cpu_to_le16(status);
3823         l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3824
3825         if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3826                 struct l2cap_info_req info;
3827                 info.type = __constant_cpu_to_le16(L2CAP_IT_FEAT_MASK);
3828
3829                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3830                 conn->info_ident = l2cap_get_ident(conn);
3831
3832                 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3833
3834                 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3835                                sizeof(info), &info);
3836         }
3837
3838         if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3839             result == L2CAP_CR_SUCCESS) {
3840                 u8 buf[128];
3841                 set_bit(CONF_REQ_SENT, &chan->conf_state);
3842                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3843                                l2cap_build_conf_req(chan, buf), buf);
3844                 chan->num_conf_req++;
3845         }
3846
3847         return chan;
3848 }
3849
3850 static int l2cap_connect_req(struct l2cap_conn *conn,
3851                              struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3852 {
3853         struct hci_dev *hdev = conn->hcon->hdev;
3854         struct hci_conn *hcon = conn->hcon;
3855
3856         if (cmd_len < sizeof(struct l2cap_conn_req))
3857                 return -EPROTO;
3858
3859         hci_dev_lock(hdev);
3860         if (test_bit(HCI_MGMT, &hdev->dev_flags) &&
3861             !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3862                 mgmt_device_connected(hdev, &hcon->dst, hcon->type,
3863                                       hcon->dst_type, 0, NULL, 0,
3864                                       hcon->dev_class);
3865         hci_dev_unlock(hdev);
3866
3867         l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3868         return 0;
3869 }
3870
3871 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3872                                     struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3873                                     u8 *data)
3874 {
3875         struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3876         u16 scid, dcid, result, status;
3877         struct l2cap_chan *chan;
3878         u8 req[128];
3879         int err;
3880
3881         if (cmd_len < sizeof(*rsp))
3882                 return -EPROTO;
3883
3884         scid   = __le16_to_cpu(rsp->scid);
3885         dcid   = __le16_to_cpu(rsp->dcid);
3886         result = __le16_to_cpu(rsp->result);
3887         status = __le16_to_cpu(rsp->status);
3888
3889         BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3890                dcid, scid, result, status);
3891
3892         mutex_lock(&conn->chan_lock);
3893
3894         if (scid) {
3895                 chan = __l2cap_get_chan_by_scid(conn, scid);
3896                 if (!chan) {
3897                         err = -EFAULT;
3898                         goto unlock;
3899                 }
3900         } else {
3901                 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3902                 if (!chan) {
3903                         err = -EFAULT;
3904                         goto unlock;
3905                 }
3906         }
3907
3908         err = 0;
3909
3910         l2cap_chan_lock(chan);
3911
3912         switch (result) {
3913         case L2CAP_CR_SUCCESS:
3914                 l2cap_state_change(chan, BT_CONFIG);
3915                 chan->ident = 0;
3916                 chan->dcid = dcid;
3917                 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3918
3919                 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3920                         break;
3921
3922                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3923                                l2cap_build_conf_req(chan, req), req);
3924                 chan->num_conf_req++;
3925                 break;
3926
3927         case L2CAP_CR_PEND:
3928                 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3929                 break;
3930
3931         default:
3932                 l2cap_chan_del(chan, ECONNREFUSED);
3933                 break;
3934         }
3935
3936         l2cap_chan_unlock(chan);
3937
3938 unlock:
3939         mutex_unlock(&conn->chan_lock);
3940
3941         return err;
3942 }
3943
3944 static inline void set_default_fcs(struct l2cap_chan *chan)
3945 {
3946         /* FCS is enabled only in ERTM or streaming mode, if one or both
3947          * sides request it.
3948          */
3949         if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3950                 chan->fcs = L2CAP_FCS_NONE;
3951         else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
3952                 chan->fcs = L2CAP_FCS_CRC16;
3953 }
3954
3955 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
3956                                     u8 ident, u16 flags)
3957 {
3958         struct l2cap_conn *conn = chan->conn;
3959
3960         BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
3961                flags);
3962
3963         clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3964         set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3965
3966         l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
3967                        l2cap_build_conf_rsp(chan, data,
3968                                             L2CAP_CONF_SUCCESS, flags), data);
3969 }
3970
3971 static inline int l2cap_config_req(struct l2cap_conn *conn,
3972                                    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3973                                    u8 *data)
3974 {
3975         struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
3976         u16 dcid, flags;
3977         u8 rsp[64];
3978         struct l2cap_chan *chan;
3979         int len, err = 0;
3980
3981         if (cmd_len < sizeof(*req))
3982                 return -EPROTO;
3983
3984         dcid  = __le16_to_cpu(req->dcid);
3985         flags = __le16_to_cpu(req->flags);
3986
3987         BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
3988
3989         chan = l2cap_get_chan_by_scid(conn, dcid);
3990         if (!chan)
3991                 return -ENOENT;
3992
3993         if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
3994                 struct l2cap_cmd_rej_cid rej;
3995
3996                 rej.reason = __constant_cpu_to_le16(L2CAP_REJ_INVALID_CID);
3997                 rej.scid = cpu_to_le16(chan->scid);
3998                 rej.dcid = cpu_to_le16(chan->dcid);
3999
4000                 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
4001                                sizeof(rej), &rej);
4002                 goto unlock;
4003         }
4004
4005         /* Reject if config buffer is too small. */
4006         len = cmd_len - sizeof(*req);
4007         if (chan->conf_len + len > sizeof(chan->conf_req)) {
4008                 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4009                                l2cap_build_conf_rsp(chan, rsp,
4010                                L2CAP_CONF_REJECT, flags), rsp);
4011                 goto unlock;
4012         }
4013
4014         /* Store config. */
4015         memcpy(chan->conf_req + chan->conf_len, req->data, len);
4016         chan->conf_len += len;
4017
4018         if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4019                 /* Incomplete config. Send empty response. */
4020                 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4021                                l2cap_build_conf_rsp(chan, rsp,
4022                                L2CAP_CONF_SUCCESS, flags), rsp);
4023                 goto unlock;
4024         }
4025
4026         /* Complete config. */
4027         len = l2cap_parse_conf_req(chan, rsp);
4028         if (len < 0) {
4029                 l2cap_send_disconn_req(chan, ECONNRESET);
4030                 goto unlock;
4031         }
4032
4033         chan->ident = cmd->ident;
4034         l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4035         chan->num_conf_rsp++;
4036
4037         /* Reset config buffer. */
4038         chan->conf_len = 0;
4039
4040         if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4041                 goto unlock;
4042
4043         if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4044                 set_default_fcs(chan);
4045
4046                 if (chan->mode == L2CAP_MODE_ERTM ||
4047                     chan->mode == L2CAP_MODE_STREAMING)
4048                         err = l2cap_ertm_init(chan);
4049
4050                 if (err < 0)
4051                         l2cap_send_disconn_req(chan, -err);
4052                 else
4053                         l2cap_chan_ready(chan);
4054
4055                 goto unlock;
4056         }
4057
4058         if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4059                 u8 buf[64];
4060                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4061                                l2cap_build_conf_req(chan, buf), buf);
4062                 chan->num_conf_req++;
4063         }
4064
4065         /* Got Conf Rsp PENDING from remote side and asume we sent
4066            Conf Rsp PENDING in the code above */
4067         if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4068             test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4069
4070                 /* check compatibility */
4071
4072                 /* Send rsp for BR/EDR channel */
4073                 if (!chan->hs_hcon)
4074                         l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4075                 else
4076                         chan->ident = cmd->ident;
4077         }
4078
4079 unlock:
4080         l2cap_chan_unlock(chan);
4081         return err;
4082 }
4083
4084 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4085                                    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4086                                    u8 *data)
4087 {
4088         struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4089         u16 scid, flags, result;
4090         struct l2cap_chan *chan;
4091         int len = cmd_len - sizeof(*rsp);
4092         int err = 0;
4093
4094         if (cmd_len < sizeof(*rsp))
4095                 return -EPROTO;
4096
4097         scid   = __le16_to_cpu(rsp->scid);
4098         flags  = __le16_to_cpu(rsp->flags);
4099         result = __le16_to_cpu(rsp->result);
4100
4101         BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4102                result, len);
4103
4104         chan = l2cap_get_chan_by_scid(conn, scid);
4105         if (!chan)
4106                 return 0;
4107
4108         switch (result) {
4109         case L2CAP_CONF_SUCCESS:
4110                 l2cap_conf_rfc_get(chan, rsp->data, len);
4111                 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4112                 break;
4113
4114         case L2CAP_CONF_PENDING:
4115                 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4116
4117                 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4118                         char buf[64];
4119
4120                         len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4121                                                    buf, &result);
4122                         if (len < 0) {
4123                                 l2cap_send_disconn_req(chan, ECONNRESET);
4124                                 goto done;
4125                         }
4126
4127                         if (!chan->hs_hcon) {
4128                                 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4129                                                         0);
4130                         } else {
4131                                 if (l2cap_check_efs(chan)) {
4132                                         amp_create_logical_link(chan);
4133                                         chan->ident = cmd->ident;
4134                                 }
4135                         }
4136                 }
4137                 goto done;
4138
4139         case L2CAP_CONF_UNACCEPT:
4140                 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4141                         char req[64];
4142
4143                         if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4144                                 l2cap_send_disconn_req(chan, ECONNRESET);
4145                                 goto done;
4146                         }
4147
4148                         /* throw out any old stored conf requests */
4149                         result = L2CAP_CONF_SUCCESS;
4150                         len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4151                                                    req, &result);
4152                         if (len < 0) {
4153                                 l2cap_send_disconn_req(chan, ECONNRESET);
4154                                 goto done;
4155                         }
4156
4157                         l2cap_send_cmd(conn, l2cap_get_ident(conn),
4158                                        L2CAP_CONF_REQ, len, req);
4159                         chan->num_conf_req++;
4160                         if (result != L2CAP_CONF_SUCCESS)
4161                                 goto done;
4162                         break;
4163                 }
4164
4165         default:
4166                 l2cap_chan_set_err(chan, ECONNRESET);
4167
4168                 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4169                 l2cap_send_disconn_req(chan, ECONNRESET);
4170                 goto done;
4171         }
4172
4173         if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4174                 goto done;
4175
4176         set_bit(CONF_INPUT_DONE, &chan->conf_state);
4177
4178         if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4179                 set_default_fcs(chan);
4180
4181                 if (chan->mode == L2CAP_MODE_ERTM ||
4182                     chan->mode == L2CAP_MODE_STREAMING)
4183                         err = l2cap_ertm_init(chan);
4184
4185                 if (err < 0)
4186                         l2cap_send_disconn_req(chan, -err);
4187                 else
4188                         l2cap_chan_ready(chan);
4189         }
4190
4191 done:
4192         l2cap_chan_unlock(chan);
4193         return err;
4194 }
4195
4196 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4197                                        struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4198                                        u8 *data)
4199 {
4200         struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4201         struct l2cap_disconn_rsp rsp;
4202         u16 dcid, scid;
4203         struct l2cap_chan *chan;
4204         struct sock *sk;
4205
4206         if (cmd_len != sizeof(*req))
4207                 return -EPROTO;
4208
4209         scid = __le16_to_cpu(req->scid);
4210         dcid = __le16_to_cpu(req->dcid);
4211
4212         BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4213
4214         mutex_lock(&conn->chan_lock);
4215
4216         chan = __l2cap_get_chan_by_scid(conn, dcid);
4217         if (!chan) {
4218                 mutex_unlock(&conn->chan_lock);
4219                 return 0;
4220         }
4221
4222         l2cap_chan_lock(chan);
4223
4224         sk = chan->sk;
4225
4226         rsp.dcid = cpu_to_le16(chan->scid);
4227         rsp.scid = cpu_to_le16(chan->dcid);
4228         l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4229
4230         lock_sock(sk);
4231         sk->sk_shutdown = SHUTDOWN_MASK;
4232         release_sock(sk);
4233
4234         l2cap_chan_hold(chan);
4235         l2cap_chan_del(chan, ECONNRESET);
4236
4237         l2cap_chan_unlock(chan);
4238
4239         chan->ops->close(chan);
4240         l2cap_chan_put(chan);
4241
4242         mutex_unlock(&conn->chan_lock);
4243
4244         return 0;
4245 }
4246
4247 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4248                                        struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4249                                        u8 *data)
4250 {
4251         struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4252         u16 dcid, scid;
4253         struct l2cap_chan *chan;
4254
4255         if (cmd_len != sizeof(*rsp))
4256                 return -EPROTO;
4257
4258         scid = __le16_to_cpu(rsp->scid);
4259         dcid = __le16_to_cpu(rsp->dcid);
4260
4261         BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4262
4263         mutex_lock(&conn->chan_lock);
4264
4265         chan = __l2cap_get_chan_by_scid(conn, scid);
4266         if (!chan) {
4267                 mutex_unlock(&conn->chan_lock);
4268                 return 0;
4269         }
4270
4271         l2cap_chan_lock(chan);
4272
4273         l2cap_chan_hold(chan);
4274         l2cap_chan_del(chan, 0);
4275
4276         l2cap_chan_unlock(chan);
4277
4278         chan->ops->close(chan);
4279         l2cap_chan_put(chan);
4280
4281         mutex_unlock(&conn->chan_lock);
4282
4283         return 0;
4284 }
4285
4286 static inline int l2cap_information_req(struct l2cap_conn *conn,
4287                                         struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4288                                         u8 *data)
4289 {
4290         struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4291         u16 type;
4292
4293         if (cmd_len != sizeof(*req))
4294                 return -EPROTO;
4295
4296         type = __le16_to_cpu(req->type);
4297
4298         BT_DBG("type 0x%4.4x", type);
4299
4300         if (type == L2CAP_IT_FEAT_MASK) {
4301                 u8 buf[8];
4302                 u32 feat_mask = l2cap_feat_mask;
4303                 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4304                 rsp->type   = __constant_cpu_to_le16(L2CAP_IT_FEAT_MASK);
4305                 rsp->result = __constant_cpu_to_le16(L2CAP_IR_SUCCESS);
4306                 if (!disable_ertm)
4307                         feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4308                                 | L2CAP_FEAT_FCS;
4309                 if (enable_hs)
4310                         feat_mask |= L2CAP_FEAT_EXT_FLOW
4311                                 | L2CAP_FEAT_EXT_WINDOW;
4312
4313                 put_unaligned_le32(feat_mask, rsp->data);
4314                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4315                                buf);
4316         } else if (type == L2CAP_IT_FIXED_CHAN) {
4317                 u8 buf[12];
4318                 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4319
4320                 if (enable_hs)
4321                         l2cap_fixed_chan[0] |= L2CAP_FC_A2MP;
4322                 else
4323                         l2cap_fixed_chan[0] &= ~L2CAP_FC_A2MP;
4324
4325                 rsp->type   = __constant_cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4326                 rsp->result = __constant_cpu_to_le16(L2CAP_IR_SUCCESS);
4327                 memcpy(rsp->data, l2cap_fixed_chan, sizeof(l2cap_fixed_chan));
4328                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4329                                buf);
4330         } else {
4331                 struct l2cap_info_rsp rsp;
4332                 rsp.type   = cpu_to_le16(type);
4333                 rsp.result = __constant_cpu_to_le16(L2CAP_IR_NOTSUPP);
4334                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4335                                &rsp);
4336         }
4337
4338         return 0;
4339 }
4340
4341 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4342                                         struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4343                                         u8 *data)
4344 {
4345         struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4346         u16 type, result;
4347
4348         if (cmd_len < sizeof(*rsp))
4349                 return -EPROTO;
4350
4351         type   = __le16_to_cpu(rsp->type);
4352         result = __le16_to_cpu(rsp->result);
4353
4354         BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4355
4356         /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4357         if (cmd->ident != conn->info_ident ||
4358             conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4359                 return 0;
4360
4361         cancel_delayed_work(&conn->info_timer);
4362
4363         if (result != L2CAP_IR_SUCCESS) {
4364                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4365                 conn->info_ident = 0;
4366
4367                 l2cap_conn_start(conn);
4368
4369                 return 0;
4370         }
4371
4372         switch (type) {
4373         case L2CAP_IT_FEAT_MASK:
4374                 conn->feat_mask = get_unaligned_le32(rsp->data);
4375
4376                 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4377                         struct l2cap_info_req req;
4378                         req.type = __constant_cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4379
4380                         conn->info_ident = l2cap_get_ident(conn);
4381
4382                         l2cap_send_cmd(conn, conn->info_ident,
4383                                        L2CAP_INFO_REQ, sizeof(req), &req);
4384                 } else {
4385                         conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4386                         conn->info_ident = 0;
4387
4388                         l2cap_conn_start(conn);
4389                 }
4390                 break;
4391
4392         case L2CAP_IT_FIXED_CHAN:
4393                 conn->fixed_chan_mask = rsp->data[0];
4394                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4395                 conn->info_ident = 0;
4396
4397                 l2cap_conn_start(conn);
4398                 break;
4399         }
4400
4401         return 0;
4402 }
4403
4404 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4405                                     struct l2cap_cmd_hdr *cmd,
4406                                     u16 cmd_len, void *data)
4407 {
4408         struct l2cap_create_chan_req *req = data;
4409         struct l2cap_create_chan_rsp rsp;
4410         struct l2cap_chan *chan;
4411         struct hci_dev *hdev;
4412         u16 psm, scid;
4413
4414         if (cmd_len != sizeof(*req))
4415                 return -EPROTO;
4416
4417         if (!enable_hs)
4418                 return -EINVAL;
4419
4420         psm = le16_to_cpu(req->psm);
4421         scid = le16_to_cpu(req->scid);
4422
4423         BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4424
4425         /* For controller id 0 make BR/EDR connection */
4426         if (req->amp_id == HCI_BREDR_ID) {
4427                 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4428                               req->amp_id);
4429                 return 0;
4430         }
4431
4432         /* Validate AMP controller id */
4433         hdev = hci_dev_get(req->amp_id);
4434         if (!hdev)
4435                 goto error;
4436
4437         if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4438                 hci_dev_put(hdev);
4439                 goto error;
4440         }
4441
4442         chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4443                              req->amp_id);
4444         if (chan) {
4445                 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4446                 struct hci_conn *hs_hcon;
4447
4448                 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK, conn->dst);
4449                 if (!hs_hcon) {
4450                         hci_dev_put(hdev);
4451                         return -EFAULT;
4452                 }
4453
4454                 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4455
4456                 mgr->bredr_chan = chan;
4457                 chan->hs_hcon = hs_hcon;
4458                 chan->fcs = L2CAP_FCS_NONE;
4459                 conn->mtu = hdev->block_mtu;
4460         }
4461
4462         hci_dev_put(hdev);
4463
4464         return 0;
4465
4466 error:
4467         rsp.dcid = 0;
4468         rsp.scid = cpu_to_le16(scid);
4469         rsp.result = __constant_cpu_to_le16(L2CAP_CR_BAD_AMP);
4470         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4471
4472         l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4473                        sizeof(rsp), &rsp);
4474
4475         return -EFAULT;
4476 }
4477
4478 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4479 {
4480         struct l2cap_move_chan_req req;
4481         u8 ident;
4482
4483         BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4484
4485         ident = l2cap_get_ident(chan->conn);
4486         chan->ident = ident;
4487
4488         req.icid = cpu_to_le16(chan->scid);
4489         req.dest_amp_id = dest_amp_id;
4490
4491         l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4492                        &req);
4493
4494         __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4495 }
4496
4497 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4498 {
4499         struct l2cap_move_chan_rsp rsp;
4500
4501         BT_DBG("chan %p, result 0x%4.4x", chan, result);
4502
4503         rsp.icid = cpu_to_le16(chan->dcid);
4504         rsp.result = cpu_to_le16(result);
4505
4506         l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4507                        sizeof(rsp), &rsp);
4508 }
4509
4510 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4511 {
4512         struct l2cap_move_chan_cfm cfm;
4513
4514         BT_DBG("chan %p, result 0x%4.4x", chan, result);
4515
4516         chan->ident = l2cap_get_ident(chan->conn);
4517
4518         cfm.icid = cpu_to_le16(chan->scid);
4519         cfm.result = cpu_to_le16(result);
4520
4521         l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4522                        sizeof(cfm), &cfm);
4523
4524         __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4525 }
4526
4527 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4528 {
4529         struct l2cap_move_chan_cfm cfm;
4530
4531         BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4532
4533         cfm.icid = cpu_to_le16(icid);
4534         cfm.result = __constant_cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4535
4536         l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4537                        sizeof(cfm), &cfm);
4538 }
4539
4540 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4541                                          u16 icid)
4542 {
4543         struct l2cap_move_chan_cfm_rsp rsp;
4544
4545         BT_DBG("icid 0x%4.4x", icid);
4546
4547         rsp.icid = cpu_to_le16(icid);
4548         l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4549 }
4550
4551 static void __release_logical_link(struct l2cap_chan *chan)
4552 {
4553         chan->hs_hchan = NULL;
4554         chan->hs_hcon = NULL;
4555
4556         /* Placeholder - release the logical link */
4557 }
4558
4559 static void l2cap_logical_fail(struct l2cap_chan *chan)
4560 {
4561         /* Logical link setup failed */
4562         if (chan->state != BT_CONNECTED) {
4563                 /* Create channel failure, disconnect */
4564                 l2cap_send_disconn_req(chan, ECONNRESET);
4565                 return;
4566         }
4567
4568         switch (chan->move_role) {
4569         case L2CAP_MOVE_ROLE_RESPONDER:
4570                 l2cap_move_done(chan);
4571                 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4572                 break;
4573         case L2CAP_MOVE_ROLE_INITIATOR:
4574                 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4575                     chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4576                         /* Remote has only sent pending or
4577                          * success responses, clean up
4578                          */
4579                         l2cap_move_done(chan);
4580                 }
4581
4582                 /* Other amp move states imply that the move
4583                  * has already aborted
4584                  */
4585                 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4586                 break;
4587         }
4588 }
4589
4590 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4591                                         struct hci_chan *hchan)
4592 {
4593         struct l2cap_conf_rsp rsp;
4594
4595         chan->hs_hchan = hchan;
4596         chan->hs_hcon->l2cap_data = chan->conn;
4597
4598         l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4599
4600         if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4601                 int err;
4602
4603                 set_default_fcs(chan);
4604
4605                 err = l2cap_ertm_init(chan);
4606                 if (err < 0)
4607                         l2cap_send_disconn_req(chan, -err);
4608                 else
4609                         l2cap_chan_ready(chan);
4610         }
4611 }
4612
4613 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4614                                       struct hci_chan *hchan)
4615 {
4616         chan->hs_hcon = hchan->conn;
4617         chan->hs_hcon->l2cap_data = chan->conn;
4618
4619         BT_DBG("move_state %d", chan->move_state);
4620
4621         switch (chan->move_state) {
4622         case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4623                 /* Move confirm will be sent after a success
4624                  * response is received
4625                  */
4626                 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4627                 break;
4628         case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4629                 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4630                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4631                 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4632                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4633                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4634                 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4635                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4636                         l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4637                 }
4638                 break;
4639         default:
4640                 /* Move was not in expected state, free the channel */
4641                 __release_logical_link(chan);
4642
4643                 chan->move_state = L2CAP_MOVE_STABLE;
4644         }
4645 }
4646
4647 /* Call with chan locked */
4648 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4649                        u8 status)
4650 {
4651         BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4652
4653         if (status) {
4654                 l2cap_logical_fail(chan);
4655                 __release_logical_link(chan);
4656                 return;
4657         }
4658
4659         if (chan->state != BT_CONNECTED) {
4660                 /* Ignore logical link if channel is on BR/EDR */
4661                 if (chan->local_amp_id)
4662                         l2cap_logical_finish_create(chan, hchan);
4663         } else {
4664                 l2cap_logical_finish_move(chan, hchan);
4665         }
4666 }
4667
4668 void l2cap_move_start(struct l2cap_chan *chan)
4669 {
4670         BT_DBG("chan %p", chan);
4671
4672         if (chan->local_amp_id == HCI_BREDR_ID) {
4673                 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4674                         return;
4675                 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4676                 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4677                 /* Placeholder - start physical link setup */
4678         } else {
4679                 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4680                 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4681                 chan->move_id = 0;
4682                 l2cap_move_setup(chan);
4683                 l2cap_send_move_chan_req(chan, 0);
4684         }
4685 }
4686
4687 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4688                             u8 local_amp_id, u8 remote_amp_id)
4689 {
4690         BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4691                local_amp_id, remote_amp_id);
4692
4693         chan->fcs = L2CAP_FCS_NONE;
4694
4695         /* Outgoing channel on AMP */
4696         if (chan->state == BT_CONNECT) {
4697                 if (result == L2CAP_CR_SUCCESS) {
4698                         chan->local_amp_id = local_amp_id;
4699                         l2cap_send_create_chan_req(chan, remote_amp_id);
4700                 } else {
4701                         /* Revert to BR/EDR connect */
4702                         l2cap_send_conn_req(chan);
4703                 }
4704
4705                 return;
4706         }
4707
4708         /* Incoming channel on AMP */
4709         if (__l2cap_no_conn_pending(chan)) {
4710                 struct l2cap_conn_rsp rsp;
4711                 char buf[128];
4712                 rsp.scid = cpu_to_le16(chan->dcid);
4713                 rsp.dcid = cpu_to_le16(chan->scid);
4714
4715                 if (result == L2CAP_CR_SUCCESS) {
4716                         /* Send successful response */
4717                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_SUCCESS);
4718                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4719                 } else {
4720                         /* Send negative response */
4721                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_NO_MEM);
4722                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4723                 }
4724
4725                 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4726                                sizeof(rsp), &rsp);
4727
4728                 if (result == L2CAP_CR_SUCCESS) {
4729                         __l2cap_state_change(chan, BT_CONFIG);
4730                         set_bit(CONF_REQ_SENT, &chan->conf_state);
4731                         l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4732                                        L2CAP_CONF_REQ,
4733                                        l2cap_build_conf_req(chan, buf), buf);
4734                         chan->num_conf_req++;
4735                 }
4736         }
4737 }
4738
4739 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4740                                    u8 remote_amp_id)
4741 {
4742         l2cap_move_setup(chan);
4743         chan->move_id = local_amp_id;
4744         chan->move_state = L2CAP_MOVE_WAIT_RSP;
4745
4746         l2cap_send_move_chan_req(chan, remote_amp_id);
4747 }
4748
4749 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4750 {
4751         struct hci_chan *hchan = NULL;
4752
4753         /* Placeholder - get hci_chan for logical link */
4754
4755         if (hchan) {
4756                 if (hchan->state == BT_CONNECTED) {
4757                         /* Logical link is ready to go */
4758                         chan->hs_hcon = hchan->conn;
4759                         chan->hs_hcon->l2cap_data = chan->conn;
4760                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4761                         l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4762
4763                         l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4764                 } else {
4765                         /* Wait for logical link to be ready */
4766                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4767                 }
4768         } else {
4769                 /* Logical link not available */
4770                 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4771         }
4772 }
4773
4774 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4775 {
4776         if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4777                 u8 rsp_result;
4778                 if (result == -EINVAL)
4779                         rsp_result = L2CAP_MR_BAD_ID;
4780                 else
4781                         rsp_result = L2CAP_MR_NOT_ALLOWED;
4782
4783                 l2cap_send_move_chan_rsp(chan, rsp_result);
4784         }
4785
4786         chan->move_role = L2CAP_MOVE_ROLE_NONE;
4787         chan->move_state = L2CAP_MOVE_STABLE;
4788
4789         /* Restart data transmission */
4790         l2cap_ertm_send(chan);
4791 }
4792
4793 /* Invoke with locked chan */
4794 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4795 {
4796         u8 local_amp_id = chan->local_amp_id;
4797         u8 remote_amp_id = chan->remote_amp_id;
4798
4799         BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4800                chan, result, local_amp_id, remote_amp_id);
4801
4802         if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4803                 l2cap_chan_unlock(chan);
4804                 return;
4805         }
4806
4807         if (chan->state != BT_CONNECTED) {
4808                 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4809         } else if (result != L2CAP_MR_SUCCESS) {
4810                 l2cap_do_move_cancel(chan, result);
4811         } else {
4812                 switch (chan->move_role) {
4813                 case L2CAP_MOVE_ROLE_INITIATOR:
4814                         l2cap_do_move_initiate(chan, local_amp_id,
4815                                                remote_amp_id);
4816                         break;
4817                 case L2CAP_MOVE_ROLE_RESPONDER:
4818                         l2cap_do_move_respond(chan, result);
4819                         break;
4820                 default:
4821                         l2cap_do_move_cancel(chan, result);
4822                         break;
4823                 }
4824         }
4825 }
4826
4827 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4828                                          struct l2cap_cmd_hdr *cmd,
4829                                          u16 cmd_len, void *data)
4830 {
4831         struct l2cap_move_chan_req *req = data;
4832         struct l2cap_move_chan_rsp rsp;
4833         struct l2cap_chan *chan;
4834         u16 icid = 0;
4835         u16 result = L2CAP_MR_NOT_ALLOWED;
4836
4837         if (cmd_len != sizeof(*req))
4838                 return -EPROTO;
4839
4840         icid = le16_to_cpu(req->icid);
4841
4842         BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4843
4844         if (!enable_hs)
4845                 return -EINVAL;
4846
4847         chan = l2cap_get_chan_by_dcid(conn, icid);
4848         if (!chan) {
4849                 rsp.icid = cpu_to_le16(icid);
4850                 rsp.result = __constant_cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4851                 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4852                                sizeof(rsp), &rsp);
4853                 return 0;
4854         }
4855
4856         chan->ident = cmd->ident;
4857
4858         if (chan->scid < L2CAP_CID_DYN_START ||
4859             chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4860             (chan->mode != L2CAP_MODE_ERTM &&
4861              chan->mode != L2CAP_MODE_STREAMING)) {
4862                 result = L2CAP_MR_NOT_ALLOWED;
4863                 goto send_move_response;
4864         }
4865
4866         if (chan->local_amp_id == req->dest_amp_id) {
4867                 result = L2CAP_MR_SAME_ID;
4868                 goto send_move_response;
4869         }
4870
4871         if (req->dest_amp_id) {
4872                 struct hci_dev *hdev;
4873                 hdev = hci_dev_get(req->dest_amp_id);
4874                 if (!hdev || hdev->dev_type != HCI_AMP ||
4875                     !test_bit(HCI_UP, &hdev->flags)) {
4876                         if (hdev)
4877                                 hci_dev_put(hdev);
4878
4879                         result = L2CAP_MR_BAD_ID;
4880                         goto send_move_response;
4881                 }
4882                 hci_dev_put(hdev);
4883         }
4884
4885         /* Detect a move collision.  Only send a collision response
4886          * if this side has "lost", otherwise proceed with the move.
4887          * The winner has the larger bd_addr.
4888          */
4889         if ((__chan_is_moving(chan) ||
4890              chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4891             bacmp(conn->src, conn->dst) > 0) {
4892                 result = L2CAP_MR_COLLISION;
4893                 goto send_move_response;
4894         }
4895
4896         chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4897         l2cap_move_setup(chan);
4898         chan->move_id = req->dest_amp_id;
4899         icid = chan->dcid;
4900
4901         if (!req->dest_amp_id) {
4902                 /* Moving to BR/EDR */
4903                 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4904                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4905                         result = L2CAP_MR_PEND;
4906                 } else {
4907                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4908                         result = L2CAP_MR_SUCCESS;
4909                 }
4910         } else {
4911                 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4912                 /* Placeholder - uncomment when amp functions are available */
4913                 /*amp_accept_physical(chan, req->dest_amp_id);*/
4914                 result = L2CAP_MR_PEND;
4915         }
4916
4917 send_move_response:
4918         l2cap_send_move_chan_rsp(chan, result);
4919
4920         l2cap_chan_unlock(chan);
4921
4922         return 0;
4923 }
4924
4925 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4926 {
4927         struct l2cap_chan *chan;
4928         struct hci_chan *hchan = NULL;
4929
4930         chan = l2cap_get_chan_by_scid(conn, icid);
4931         if (!chan) {
4932                 l2cap_send_move_chan_cfm_icid(conn, icid);
4933                 return;
4934         }
4935
4936         __clear_chan_timer(chan);
4937         if (result == L2CAP_MR_PEND)
4938                 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4939
4940         switch (chan->move_state) {
4941         case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4942                 /* Move confirm will be sent when logical link
4943                  * is complete.
4944                  */
4945                 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4946                 break;
4947         case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4948                 if (result == L2CAP_MR_PEND) {
4949                         break;
4950                 } else if (test_bit(CONN_LOCAL_BUSY,
4951                                     &chan->conn_state)) {
4952                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4953                 } else {
4954                         /* Logical link is up or moving to BR/EDR,
4955                          * proceed with move
4956                          */
4957                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4958                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4959                 }
4960                 break;
4961         case L2CAP_MOVE_WAIT_RSP:
4962                 /* Moving to AMP */
4963                 if (result == L2CAP_MR_SUCCESS) {
4964                         /* Remote is ready, send confirm immediately
4965                          * after logical link is ready
4966                          */
4967                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4968                 } else {
4969                         /* Both logical link and move success
4970                          * are required to confirm
4971                          */
4972                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
4973                 }
4974
4975                 /* Placeholder - get hci_chan for logical link */
4976                 if (!hchan) {
4977                         /* Logical link not available */
4978                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4979                         break;
4980                 }
4981
4982                 /* If the logical link is not yet connected, do not
4983                  * send confirmation.
4984                  */
4985                 if (hchan->state != BT_CONNECTED)
4986                         break;
4987
4988                 /* Logical link is already ready to go */
4989
4990                 chan->hs_hcon = hchan->conn;
4991                 chan->hs_hcon->l2cap_data = chan->conn;
4992
4993                 if (result == L2CAP_MR_SUCCESS) {
4994                         /* Can confirm now */
4995                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4996                 } else {
4997                         /* Now only need move success
4998                          * to confirm
4999                          */
5000                         chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5001                 }
5002
5003                 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5004                 break;
5005         default:
5006                 /* Any other amp move state means the move failed. */
5007                 chan->move_id = chan->local_amp_id;
5008                 l2cap_move_done(chan);
5009                 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5010         }
5011
5012         l2cap_chan_unlock(chan);
5013 }
5014
5015 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5016                             u16 result)
5017 {
5018         struct l2cap_chan *chan;
5019
5020         chan = l2cap_get_chan_by_ident(conn, ident);
5021         if (!chan) {
5022                 /* Could not locate channel, icid is best guess */
5023                 l2cap_send_move_chan_cfm_icid(conn, icid);
5024                 return;
5025         }
5026
5027         __clear_chan_timer(chan);
5028
5029         if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5030                 if (result == L2CAP_MR_COLLISION) {
5031                         chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5032                 } else {
5033                         /* Cleanup - cancel move */
5034                         chan->move_id = chan->local_amp_id;
5035                         l2cap_move_done(chan);
5036                 }
5037         }
5038
5039         l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5040
5041         l2cap_chan_unlock(chan);
5042 }
5043
5044 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5045                                   struct l2cap_cmd_hdr *cmd,
5046                                   u16 cmd_len, void *data)
5047 {
5048         struct l2cap_move_chan_rsp *rsp = data;
5049         u16 icid, result;
5050
5051         if (cmd_len != sizeof(*rsp))
5052                 return -EPROTO;
5053
5054         icid = le16_to_cpu(rsp->icid);
5055         result = le16_to_cpu(rsp->result);
5056
5057         BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5058
5059         if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5060                 l2cap_move_continue(conn, icid, result);
5061         else
5062                 l2cap_move_fail(conn, cmd->ident, icid, result);
5063
5064         return 0;
5065 }
5066
5067 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5068                                       struct l2cap_cmd_hdr *cmd,
5069                                       u16 cmd_len, void *data)
5070 {
5071         struct l2cap_move_chan_cfm *cfm = data;
5072         struct l2cap_chan *chan;
5073         u16 icid, result;
5074
5075         if (cmd_len != sizeof(*cfm))
5076                 return -EPROTO;
5077
5078         icid = le16_to_cpu(cfm->icid);
5079         result = le16_to_cpu(cfm->result);
5080
5081         BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5082
5083         chan = l2cap_get_chan_by_dcid(conn, icid);
5084         if (!chan) {
5085                 /* Spec requires a response even if the icid was not found */
5086                 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5087                 return 0;
5088         }
5089
5090         if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5091                 if (result == L2CAP_MC_CONFIRMED) {
5092                         chan->local_amp_id = chan->move_id;
5093                         if (!chan->local_amp_id)
5094                                 __release_logical_link(chan);
5095                 } else {
5096                         chan->move_id = chan->local_amp_id;
5097                 }
5098
5099                 l2cap_move_done(chan);
5100         }
5101
5102         l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5103
5104         l2cap_chan_unlock(chan);
5105
5106         return 0;
5107 }
5108
5109 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5110                                                  struct l2cap_cmd_hdr *cmd,
5111                                                  u16 cmd_len, void *data)
5112 {
5113         struct l2cap_move_chan_cfm_rsp *rsp = data;
5114         struct l2cap_chan *chan;
5115         u16 icid;
5116
5117         if (cmd_len != sizeof(*rsp))
5118                 return -EPROTO;
5119
5120         icid = le16_to_cpu(rsp->icid);
5121
5122         BT_DBG("icid 0x%4.4x", icid);
5123
5124         chan = l2cap_get_chan_by_scid(conn, icid);
5125         if (!chan)
5126                 return 0;
5127
5128         __clear_chan_timer(chan);
5129
5130         if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5131                 chan->local_amp_id = chan->move_id;
5132
5133                 if (!chan->local_amp_id && chan->hs_hchan)
5134                         __release_logical_link(chan);
5135
5136                 l2cap_move_done(chan);
5137         }
5138
5139         l2cap_chan_unlock(chan);
5140
5141         return 0;
5142 }
5143
5144 static inline int l2cap_check_conn_param(u16 min, u16 max, u16 latency,
5145                                          u16 to_multiplier)
5146 {
5147         u16 max_latency;
5148
5149         if (min > max || min < 6 || max > 3200)
5150                 return -EINVAL;
5151
5152         if (to_multiplier < 10 || to_multiplier > 3200)
5153                 return -EINVAL;
5154
5155         if (max >= to_multiplier * 8)
5156                 return -EINVAL;
5157
5158         max_latency = (to_multiplier * 8 / max) - 1;
5159         if (latency > 499 || latency > max_latency)
5160                 return -EINVAL;
5161
5162         return 0;
5163 }
5164
5165 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5166                                               struct l2cap_cmd_hdr *cmd,
5167                                               u8 *data)
5168 {
5169         struct hci_conn *hcon = conn->hcon;
5170         struct l2cap_conn_param_update_req *req;
5171         struct l2cap_conn_param_update_rsp rsp;
5172         u16 min, max, latency, to_multiplier, cmd_len;
5173         int err;
5174
5175         if (!(hcon->link_mode & HCI_LM_MASTER))
5176                 return -EINVAL;
5177
5178         cmd_len = __le16_to_cpu(cmd->len);
5179         if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5180                 return -EPROTO;
5181
5182         req = (struct l2cap_conn_param_update_req *) data;
5183         min             = __le16_to_cpu(req->min);
5184         max             = __le16_to_cpu(req->max);
5185         latency         = __le16_to_cpu(req->latency);
5186         to_multiplier   = __le16_to_cpu(req->to_multiplier);
5187
5188         BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5189                min, max, latency, to_multiplier);
5190
5191         memset(&rsp, 0, sizeof(rsp));
5192
5193         err = l2cap_check_conn_param(min, max, latency, to_multiplier);
5194         if (err)
5195                 rsp.result = __constant_cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5196         else
5197                 rsp.result = __constant_cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5198
5199         l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5200                        sizeof(rsp), &rsp);
5201
5202         if (!err)
5203                 hci_le_conn_update(hcon, min, max, latency, to_multiplier);
5204
5205         return 0;
5206 }
5207
5208 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5209                                       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5210                                       u8 *data)
5211 {
5212         int err = 0;
5213
5214         switch (cmd->code) {
5215         case L2CAP_COMMAND_REJ:
5216                 l2cap_command_rej(conn, cmd, cmd_len, data);
5217                 break;
5218
5219         case L2CAP_CONN_REQ:
5220                 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5221                 break;
5222
5223         case L2CAP_CONN_RSP:
5224         case L2CAP_CREATE_CHAN_RSP:
5225                 err = l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5226                 break;
5227
5228         case L2CAP_CONF_REQ:
5229                 err = l2cap_config_req(conn, cmd, cmd_len, data);
5230                 break;
5231
5232         case L2CAP_CONF_RSP:
5233                 err = l2cap_config_rsp(conn, cmd, cmd_len, data);
5234                 break;
5235
5236         case L2CAP_DISCONN_REQ:
5237                 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5238                 break;
5239
5240         case L2CAP_DISCONN_RSP:
5241                 err = l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5242                 break;
5243
5244         case L2CAP_ECHO_REQ:
5245                 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5246                 break;
5247
5248         case L2CAP_ECHO_RSP:
5249                 break;
5250
5251         case L2CAP_INFO_REQ:
5252                 err = l2cap_information_req(conn, cmd, cmd_len, data);
5253                 break;
5254
5255         case L2CAP_INFO_RSP:
5256                 err = l2cap_information_rsp(conn, cmd, cmd_len, data);
5257                 break;
5258
5259         case L2CAP_CREATE_CHAN_REQ:
5260                 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5261                 break;
5262
5263         case L2CAP_MOVE_CHAN_REQ:
5264                 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5265                 break;
5266
5267         case L2CAP_MOVE_CHAN_RSP:
5268                 err = l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5269                 break;
5270
5271         case L2CAP_MOVE_CHAN_CFM:
5272                 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5273                 break;
5274
5275         case L2CAP_MOVE_CHAN_CFM_RSP:
5276                 err = l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5277                 break;
5278
5279         default:
5280                 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5281                 err = -EINVAL;
5282                 break;
5283         }
5284
5285         return err;
5286 }
5287
5288 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5289                                    struct l2cap_cmd_hdr *cmd, u8 *data)
5290 {
5291         switch (cmd->code) {
5292         case L2CAP_COMMAND_REJ:
5293                 return 0;
5294
5295         case L2CAP_CONN_PARAM_UPDATE_REQ:
5296                 return l2cap_conn_param_update_req(conn, cmd, data);
5297
5298         case L2CAP_CONN_PARAM_UPDATE_RSP:
5299                 return 0;
5300
5301         default:
5302                 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5303                 return -EINVAL;
5304         }
5305 }
5306
5307 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5308                                         struct sk_buff *skb)
5309 {
5310         u8 *data = skb->data;
5311         int len = skb->len;
5312         struct l2cap_cmd_hdr cmd;
5313         int err;
5314
5315         l2cap_raw_recv(conn, skb);
5316
5317         while (len >= L2CAP_CMD_HDR_SIZE) {
5318                 u16 cmd_len;
5319                 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5320                 data += L2CAP_CMD_HDR_SIZE;
5321                 len  -= L2CAP_CMD_HDR_SIZE;
5322
5323                 cmd_len = le16_to_cpu(cmd.len);
5324
5325                 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5326                        cmd.ident);
5327
5328                 if (cmd_len > len || !cmd.ident) {
5329                         BT_DBG("corrupted command");
5330                         break;
5331                 }
5332
5333                 err = l2cap_le_sig_cmd(conn, &cmd, data);
5334                 if (err) {
5335                         struct l2cap_cmd_rej_unk rej;
5336
5337                         BT_ERR("Wrong link type (%d)", err);
5338
5339                         /* FIXME: Map err to a valid reason */
5340                         rej.reason = __constant_cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5341                         l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5342                                        sizeof(rej), &rej);
5343                 }
5344
5345                 data += cmd_len;
5346                 len  -= cmd_len;
5347         }
5348
5349         kfree_skb(skb);
5350 }
5351
5352 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5353                                      struct sk_buff *skb)
5354 {
5355         u8 *data = skb->data;
5356         int len = skb->len;
5357         struct l2cap_cmd_hdr cmd;
5358         int err;
5359
5360         l2cap_raw_recv(conn, skb);
5361
5362         while (len >= L2CAP_CMD_HDR_SIZE) {
5363                 u16 cmd_len;
5364                 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5365                 data += L2CAP_CMD_HDR_SIZE;
5366                 len  -= L2CAP_CMD_HDR_SIZE;
5367
5368                 cmd_len = le16_to_cpu(cmd.len);
5369
5370                 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5371                        cmd.ident);
5372
5373                 if (cmd_len > len || !cmd.ident) {
5374                         BT_DBG("corrupted command");
5375                         break;
5376                 }
5377
5378                 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5379                 if (err) {
5380                         struct l2cap_cmd_rej_unk rej;
5381
5382                         BT_ERR("Wrong link type (%d)", err);
5383
5384                         /* FIXME: Map err to a valid reason */
5385                         rej.reason = __constant_cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5386                         l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5387                                        sizeof(rej), &rej);
5388                 }
5389
5390                 data += cmd_len;
5391                 len  -= cmd_len;
5392         }
5393
5394         kfree_skb(skb);
5395 }
5396
5397 static int l2cap_check_fcs(struct l2cap_chan *chan,  struct sk_buff *skb)
5398 {
5399         u16 our_fcs, rcv_fcs;
5400         int hdr_size;
5401
5402         if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5403                 hdr_size = L2CAP_EXT_HDR_SIZE;
5404         else
5405                 hdr_size = L2CAP_ENH_HDR_SIZE;
5406
5407         if (chan->fcs == L2CAP_FCS_CRC16) {
5408                 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5409                 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5410                 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5411
5412                 if (our_fcs != rcv_fcs)
5413                         return -EBADMSG;
5414         }
5415         return 0;
5416 }
5417
5418 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5419 {
5420         struct l2cap_ctrl control;
5421
5422         BT_DBG("chan %p", chan);
5423
5424         memset(&control, 0, sizeof(control));
5425         control.sframe = 1;
5426         control.final = 1;
5427         control.reqseq = chan->buffer_seq;
5428         set_bit(CONN_SEND_FBIT, &chan->conn_state);
5429
5430         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5431                 control.super = L2CAP_SUPER_RNR;
5432                 l2cap_send_sframe(chan, &control);
5433         }
5434
5435         if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5436             chan->unacked_frames > 0)
5437                 __set_retrans_timer(chan);
5438
5439         /* Send pending iframes */
5440         l2cap_ertm_send(chan);
5441
5442         if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5443             test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5444                 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5445                  * send it now.
5446                  */
5447                 control.super = L2CAP_SUPER_RR;
5448                 l2cap_send_sframe(chan, &control);
5449         }
5450 }
5451
5452 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5453                             struct sk_buff **last_frag)
5454 {
5455         /* skb->len reflects data in skb as well as all fragments
5456          * skb->data_len reflects only data in fragments
5457          */
5458         if (!skb_has_frag_list(skb))
5459                 skb_shinfo(skb)->frag_list = new_frag;
5460
5461         new_frag->next = NULL;
5462
5463         (*last_frag)->next = new_frag;
5464         *last_frag = new_frag;
5465
5466         skb->len += new_frag->len;
5467         skb->data_len += new_frag->len;
5468         skb->truesize += new_frag->truesize;
5469 }
5470
5471 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5472                                 struct l2cap_ctrl *control)
5473 {
5474         int err = -EINVAL;
5475
5476         switch (control->sar) {
5477         case L2CAP_SAR_UNSEGMENTED:
5478                 if (chan->sdu)
5479                         break;
5480
5481                 err = chan->ops->recv(chan, skb);
5482                 break;
5483
5484         case L2CAP_SAR_START:
5485                 if (chan->sdu)
5486                         break;
5487
5488                 chan->sdu_len = get_unaligned_le16(skb->data);
5489                 skb_pull(skb, L2CAP_SDULEN_SIZE);
5490
5491                 if (chan->sdu_len > chan->imtu) {
5492                         err = -EMSGSIZE;
5493                         break;
5494                 }
5495
5496                 if (skb->len >= chan->sdu_len)
5497                         break;
5498
5499                 chan->sdu = skb;
5500                 chan->sdu_last_frag = skb;
5501
5502                 skb = NULL;
5503                 err = 0;
5504                 break;
5505
5506         case L2CAP_SAR_CONTINUE:
5507                 if (!chan->sdu)
5508                         break;
5509
5510                 append_skb_frag(chan->sdu, skb,
5511                                 &chan->sdu_last_frag);
5512                 skb = NULL;
5513
5514                 if (chan->sdu->len >= chan->sdu_len)
5515                         break;
5516
5517                 err = 0;
5518                 break;
5519
5520         case L2CAP_SAR_END:
5521                 if (!chan->sdu)
5522                         break;
5523
5524                 append_skb_frag(chan->sdu, skb,
5525                                 &chan->sdu_last_frag);
5526                 skb = NULL;
5527
5528                 if (chan->sdu->len != chan->sdu_len)
5529                         break;
5530
5531                 err = chan->ops->recv(chan, chan->sdu);
5532
5533                 if (!err) {
5534                         /* Reassembly complete */
5535                         chan->sdu = NULL;
5536                         chan->sdu_last_frag = NULL;
5537                         chan->sdu_len = 0;
5538                 }
5539                 break;
5540         }
5541
5542         if (err) {
5543                 kfree_skb(skb);
5544                 kfree_skb(chan->sdu);
5545                 chan->sdu = NULL;
5546                 chan->sdu_last_frag = NULL;
5547                 chan->sdu_len = 0;
5548         }
5549
5550         return err;
5551 }
5552
5553 static int l2cap_resegment(struct l2cap_chan *chan)
5554 {
5555         /* Placeholder */
5556         return 0;
5557 }
5558
5559 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5560 {
5561         u8 event;
5562
5563         if (chan->mode != L2CAP_MODE_ERTM)
5564                 return;
5565
5566         event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5567         l2cap_tx(chan, NULL, NULL, event);
5568 }
5569
5570 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5571 {
5572         int err = 0;
5573         /* Pass sequential frames to l2cap_reassemble_sdu()
5574          * until a gap is encountered.
5575          */
5576
5577         BT_DBG("chan %p", chan);
5578
5579         while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5580                 struct sk_buff *skb;
5581                 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5582                        chan->buffer_seq, skb_queue_len(&chan->srej_q));
5583
5584                 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5585
5586                 if (!skb)
5587                         break;
5588
5589                 skb_unlink(skb, &chan->srej_q);
5590                 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5591                 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->control);
5592                 if (err)
5593                         break;
5594         }
5595
5596         if (skb_queue_empty(&chan->srej_q)) {
5597                 chan->rx_state = L2CAP_RX_STATE_RECV;
5598                 l2cap_send_ack(chan);
5599         }
5600
5601         return err;
5602 }
5603
5604 static void l2cap_handle_srej(struct l2cap_chan *chan,
5605                               struct l2cap_ctrl *control)
5606 {
5607         struct sk_buff *skb;
5608
5609         BT_DBG("chan %p, control %p", chan, control);
5610
5611         if (control->reqseq == chan->next_tx_seq) {
5612                 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5613                 l2cap_send_disconn_req(chan, ECONNRESET);
5614                 return;
5615         }
5616
5617         skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5618
5619         if (skb == NULL) {
5620                 BT_DBG("Seq %d not available for retransmission",
5621                        control->reqseq);
5622                 return;
5623         }
5624
5625         if (chan->max_tx != 0 && bt_cb(skb)->control.retries >= chan->max_tx) {
5626                 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5627                 l2cap_send_disconn_req(chan, ECONNRESET);
5628                 return;
5629         }
5630
5631         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5632
5633         if (control->poll) {
5634                 l2cap_pass_to_tx(chan, control);
5635
5636                 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5637                 l2cap_retransmit(chan, control);
5638                 l2cap_ertm_send(chan);
5639
5640                 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5641                         set_bit(CONN_SREJ_ACT, &chan->conn_state);
5642                         chan->srej_save_reqseq = control->reqseq;
5643                 }
5644         } else {
5645                 l2cap_pass_to_tx_fbit(chan, control);
5646
5647                 if (control->final) {
5648                         if (chan->srej_save_reqseq != control->reqseq ||
5649                             !test_and_clear_bit(CONN_SREJ_ACT,
5650                                                 &chan->conn_state))
5651                                 l2cap_retransmit(chan, control);
5652                 } else {
5653                         l2cap_retransmit(chan, control);
5654                         if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5655                                 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5656                                 chan->srej_save_reqseq = control->reqseq;
5657                         }
5658                 }
5659         }
5660 }
5661
5662 static void l2cap_handle_rej(struct l2cap_chan *chan,
5663                              struct l2cap_ctrl *control)
5664 {
5665         struct sk_buff *skb;
5666
5667         BT_DBG("chan %p, control %p", chan, control);
5668
5669         if (control->reqseq == chan->next_tx_seq) {
5670                 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5671                 l2cap_send_disconn_req(chan, ECONNRESET);
5672                 return;
5673         }
5674
5675         skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5676
5677         if (chan->max_tx && skb &&
5678             bt_cb(skb)->control.retries >= chan->max_tx) {
5679                 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5680                 l2cap_send_disconn_req(chan, ECONNRESET);
5681                 return;
5682         }
5683
5684         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5685
5686         l2cap_pass_to_tx(chan, control);
5687
5688         if (control->final) {
5689                 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
5690                         l2cap_retransmit_all(chan, control);
5691         } else {
5692                 l2cap_retransmit_all(chan, control);
5693                 l2cap_ertm_send(chan);
5694                 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
5695                         set_bit(CONN_REJ_ACT, &chan->conn_state);
5696         }
5697 }
5698
5699 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
5700 {
5701         BT_DBG("chan %p, txseq %d", chan, txseq);
5702
5703         BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
5704                chan->expected_tx_seq);
5705
5706         if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
5707                 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
5708                     chan->tx_win) {
5709                         /* See notes below regarding "double poll" and
5710                          * invalid packets.
5711                          */
5712                         if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
5713                                 BT_DBG("Invalid/Ignore - after SREJ");
5714                                 return L2CAP_TXSEQ_INVALID_IGNORE;
5715                         } else {
5716                                 BT_DBG("Invalid - in window after SREJ sent");
5717                                 return L2CAP_TXSEQ_INVALID;
5718                         }
5719                 }
5720
5721                 if (chan->srej_list.head == txseq) {
5722                         BT_DBG("Expected SREJ");
5723                         return L2CAP_TXSEQ_EXPECTED_SREJ;
5724                 }
5725
5726                 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
5727                         BT_DBG("Duplicate SREJ - txseq already stored");
5728                         return L2CAP_TXSEQ_DUPLICATE_SREJ;
5729                 }
5730
5731                 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
5732                         BT_DBG("Unexpected SREJ - not requested");
5733                         return L2CAP_TXSEQ_UNEXPECTED_SREJ;
5734                 }
5735         }
5736
5737         if (chan->expected_tx_seq == txseq) {
5738                 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
5739                     chan->tx_win) {
5740                         BT_DBG("Invalid - txseq outside tx window");
5741                         return L2CAP_TXSEQ_INVALID;
5742                 } else {
5743                         BT_DBG("Expected");
5744                         return L2CAP_TXSEQ_EXPECTED;
5745                 }
5746         }
5747
5748         if (__seq_offset(chan, txseq, chan->last_acked_seq) <
5749             __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
5750                 BT_DBG("Duplicate - expected_tx_seq later than txseq");
5751                 return L2CAP_TXSEQ_DUPLICATE;
5752         }
5753
5754         if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
5755                 /* A source of invalid packets is a "double poll" condition,
5756                  * where delays cause us to send multiple poll packets.  If
5757                  * the remote stack receives and processes both polls,
5758                  * sequence numbers can wrap around in such a way that a
5759                  * resent frame has a sequence number that looks like new data
5760                  * with a sequence gap.  This would trigger an erroneous SREJ
5761                  * request.
5762                  *
5763                  * Fortunately, this is impossible with a tx window that's
5764                  * less than half of the maximum sequence number, which allows
5765                  * invalid frames to be safely ignored.
5766                  *
5767                  * With tx window sizes greater than half of the tx window
5768                  * maximum, the frame is invalid and cannot be ignored.  This
5769                  * causes a disconnect.
5770                  */
5771
5772                 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
5773                         BT_DBG("Invalid/Ignore - txseq outside tx window");
5774                         return L2CAP_TXSEQ_INVALID_IGNORE;
5775                 } else {
5776                         BT_DBG("Invalid - txseq outside tx window");
5777                         return L2CAP_TXSEQ_INVALID;
5778                 }
5779         } else {
5780                 BT_DBG("Unexpected - txseq indicates missing frames");
5781                 return L2CAP_TXSEQ_UNEXPECTED;
5782         }
5783 }
5784
5785 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
5786                                struct l2cap_ctrl *control,
5787                                struct sk_buff *skb, u8 event)
5788 {
5789         int err = 0;
5790         bool skb_in_use = 0;
5791
5792         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
5793                event);
5794
5795         switch (event) {
5796         case L2CAP_EV_RECV_IFRAME:
5797                 switch (l2cap_classify_txseq(chan, control->txseq)) {
5798                 case L2CAP_TXSEQ_EXPECTED:
5799                         l2cap_pass_to_tx(chan, control);
5800
5801                         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5802                                 BT_DBG("Busy, discarding expected seq %d",
5803                                        control->txseq);
5804                                 break;
5805                         }
5806
5807                         chan->expected_tx_seq = __next_seq(chan,
5808                                                            control->txseq);
5809
5810                         chan->buffer_seq = chan->expected_tx_seq;
5811                         skb_in_use = 1;
5812
5813                         err = l2cap_reassemble_sdu(chan, skb, control);
5814                         if (err)
5815                                 break;
5816
5817                         if (control->final) {
5818                                 if (!test_and_clear_bit(CONN_REJ_ACT,
5819                                                         &chan->conn_state)) {
5820                                         control->final = 0;
5821                                         l2cap_retransmit_all(chan, control);
5822                                         l2cap_ertm_send(chan);
5823                                 }
5824                         }
5825
5826                         if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
5827                                 l2cap_send_ack(chan);
5828                         break;
5829                 case L2CAP_TXSEQ_UNEXPECTED:
5830                         l2cap_pass_to_tx(chan, control);
5831
5832                         /* Can't issue SREJ frames in the local busy state.
5833                          * Drop this frame, it will be seen as missing
5834                          * when local busy is exited.
5835                          */
5836                         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5837                                 BT_DBG("Busy, discarding unexpected seq %d",
5838                                        control->txseq);
5839                                 break;
5840                         }
5841
5842                         /* There was a gap in the sequence, so an SREJ
5843                          * must be sent for each missing frame.  The
5844                          * current frame is stored for later use.
5845                          */
5846                         skb_queue_tail(&chan->srej_q, skb);
5847                         skb_in_use = 1;
5848                         BT_DBG("Queued %p (queue len %d)", skb,
5849                                skb_queue_len(&chan->srej_q));
5850
5851                         clear_bit(CONN_SREJ_ACT, &chan->conn_state);
5852                         l2cap_seq_list_clear(&chan->srej_list);
5853                         l2cap_send_srej(chan, control->txseq);
5854
5855                         chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
5856                         break;
5857                 case L2CAP_TXSEQ_DUPLICATE:
5858                         l2cap_pass_to_tx(chan, control);
5859                         break;
5860                 case L2CAP_TXSEQ_INVALID_IGNORE:
5861                         break;
5862                 case L2CAP_TXSEQ_INVALID:
5863                 default:
5864                         l2cap_send_disconn_req(chan, ECONNRESET);
5865                         break;
5866                 }
5867                 break;
5868         case L2CAP_EV_RECV_RR:
5869                 l2cap_pass_to_tx(chan, control);
5870                 if (control->final) {
5871                         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5872
5873                         if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
5874                             !__chan_is_moving(chan)) {
5875                                 control->final = 0;
5876                                 l2cap_retransmit_all(chan, control);
5877                         }
5878
5879                         l2cap_ertm_send(chan);
5880                 } else if (control->poll) {
5881                         l2cap_send_i_or_rr_or_rnr(chan);
5882                 } else {
5883                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
5884                                                &chan->conn_state) &&
5885                             chan->unacked_frames)
5886                                 __set_retrans_timer(chan);
5887
5888                         l2cap_ertm_send(chan);
5889                 }
5890                 break;
5891         case L2CAP_EV_RECV_RNR:
5892                 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5893                 l2cap_pass_to_tx(chan, control);
5894                 if (control && control->poll) {
5895                         set_bit(CONN_SEND_FBIT, &chan->conn_state);
5896                         l2cap_send_rr_or_rnr(chan, 0);
5897                 }
5898                 __clear_retrans_timer(chan);
5899                 l2cap_seq_list_clear(&chan->retrans_list);
5900                 break;
5901         case L2CAP_EV_RECV_REJ:
5902                 l2cap_handle_rej(chan, control);
5903                 break;
5904         case L2CAP_EV_RECV_SREJ:
5905                 l2cap_handle_srej(chan, control);
5906                 break;
5907         default:
5908                 break;
5909         }
5910
5911         if (skb && !skb_in_use) {
5912                 BT_DBG("Freeing %p", skb);
5913                 kfree_skb(skb);
5914         }
5915
5916         return err;
5917 }
5918
5919 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
5920                                     struct l2cap_ctrl *control,
5921                                     struct sk_buff *skb, u8 event)
5922 {
5923         int err = 0;
5924         u16 txseq = control->txseq;
5925         bool skb_in_use = 0;
5926
5927         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
5928                event);
5929
5930         switch (event) {
5931         case L2CAP_EV_RECV_IFRAME:
5932                 switch (l2cap_classify_txseq(chan, txseq)) {
5933                 case L2CAP_TXSEQ_EXPECTED:
5934                         /* Keep frame for reassembly later */
5935                         l2cap_pass_to_tx(chan, control);
5936                         skb_queue_tail(&chan->srej_q, skb);
5937                         skb_in_use = 1;
5938                         BT_DBG("Queued %p (queue len %d)", skb,
5939                                skb_queue_len(&chan->srej_q));
5940
5941                         chan->expected_tx_seq = __next_seq(chan, txseq);
5942                         break;
5943                 case L2CAP_TXSEQ_EXPECTED_SREJ:
5944                         l2cap_seq_list_pop(&chan->srej_list);
5945
5946                         l2cap_pass_to_tx(chan, control);
5947                         skb_queue_tail(&chan->srej_q, skb);
5948                         skb_in_use = 1;
5949                         BT_DBG("Queued %p (queue len %d)", skb,
5950                                skb_queue_len(&chan->srej_q));
5951
5952                         err = l2cap_rx_queued_iframes(chan);
5953                         if (err)
5954                                 break;
5955
5956                         break;
5957                 case L2CAP_TXSEQ_UNEXPECTED:
5958                         /* Got a frame that can't be reassembled yet.
5959                          * Save it for later, and send SREJs to cover
5960                          * the missing frames.
5961                          */
5962                         skb_queue_tail(&chan->srej_q, skb);
5963                         skb_in_use = 1;
5964                         BT_DBG("Queued %p (queue len %d)", skb,
5965                                skb_queue_len(&chan->srej_q));
5966
5967                         l2cap_pass_to_tx(chan, control);
5968                         l2cap_send_srej(chan, control->txseq);
5969                         break;
5970                 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
5971                         /* This frame was requested with an SREJ, but
5972                          * some expected retransmitted frames are
5973                          * missing.  Request retransmission of missing
5974                          * SREJ'd frames.
5975                          */
5976                         skb_queue_tail(&chan->srej_q, skb);
5977                         skb_in_use = 1;
5978                         BT_DBG("Queued %p (queue len %d)", skb,
5979                                skb_queue_len(&chan->srej_q));
5980
5981                         l2cap_pass_to_tx(chan, control);
5982                         l2cap_send_srej_list(chan, control->txseq);
5983                         break;
5984                 case L2CAP_TXSEQ_DUPLICATE_SREJ:
5985                         /* We've already queued this frame.  Drop this copy. */
5986                         l2cap_pass_to_tx(chan, control);
5987                         break;
5988                 case L2CAP_TXSEQ_DUPLICATE:
5989                         /* Expecting a later sequence number, so this frame
5990                          * was already received.  Ignore it completely.
5991                          */
5992                         break;
5993                 case L2CAP_TXSEQ_INVALID_IGNORE:
5994                         break;
5995                 case L2CAP_TXSEQ_INVALID:
5996                 default:
5997                         l2cap_send_disconn_req(chan, ECONNRESET);
5998                         break;
5999                 }
6000                 break;
6001         case L2CAP_EV_RECV_RR:
6002                 l2cap_pass_to_tx(chan, control);
6003                 if (control->final) {
6004                         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6005
6006                         if (!test_and_clear_bit(CONN_REJ_ACT,
6007                                                 &chan->conn_state)) {
6008                                 control->final = 0;
6009                                 l2cap_retransmit_all(chan, control);
6010                         }
6011
6012                         l2cap_ertm_send(chan);
6013                 } else if (control->poll) {
6014                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
6015                                                &chan->conn_state) &&
6016                             chan->unacked_frames) {
6017                                 __set_retrans_timer(chan);
6018                         }
6019
6020                         set_bit(CONN_SEND_FBIT, &chan->conn_state);
6021                         l2cap_send_srej_tail(chan);
6022                 } else {
6023                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
6024                                                &chan->conn_state) &&
6025                             chan->unacked_frames)
6026                                 __set_retrans_timer(chan);
6027
6028                         l2cap_send_ack(chan);
6029                 }
6030                 break;
6031         case L2CAP_EV_RECV_RNR:
6032                 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6033                 l2cap_pass_to_tx(chan, control);
6034                 if (control->poll) {
6035                         l2cap_send_srej_tail(chan);
6036                 } else {
6037                         struct l2cap_ctrl rr_control;
6038                         memset(&rr_control, 0, sizeof(rr_control));
6039                         rr_control.sframe = 1;
6040                         rr_control.super = L2CAP_SUPER_RR;
6041                         rr_control.reqseq = chan->buffer_seq;
6042                         l2cap_send_sframe(chan, &rr_control);
6043                 }
6044
6045                 break;
6046         case L2CAP_EV_RECV_REJ:
6047                 l2cap_handle_rej(chan, control);
6048                 break;
6049         case L2CAP_EV_RECV_SREJ:
6050                 l2cap_handle_srej(chan, control);
6051                 break;
6052         }
6053
6054         if (skb && !skb_in_use) {
6055                 BT_DBG("Freeing %p", skb);
6056                 kfree_skb(skb);
6057         }
6058
6059         return err;
6060 }
6061
6062 static int l2cap_finish_move(struct l2cap_chan *chan)
6063 {
6064         BT_DBG("chan %p", chan);
6065
6066         chan->rx_state = L2CAP_RX_STATE_RECV;
6067
6068         if (chan->hs_hcon)
6069                 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6070         else
6071                 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6072
6073         return l2cap_resegment(chan);
6074 }
6075
6076 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6077                                  struct l2cap_ctrl *control,
6078                                  struct sk_buff *skb, u8 event)
6079 {
6080         int err;
6081
6082         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6083                event);
6084
6085         if (!control->poll)
6086                 return -EPROTO;
6087
6088         l2cap_process_reqseq(chan, control->reqseq);
6089
6090         if (!skb_queue_empty(&chan->tx_q))
6091                 chan->tx_send_head = skb_peek(&chan->tx_q);
6092         else
6093                 chan->tx_send_head = NULL;
6094
6095         /* Rewind next_tx_seq to the point expected
6096          * by the receiver.
6097          */
6098         chan->next_tx_seq = control->reqseq;
6099         chan->unacked_frames = 0;
6100
6101         err = l2cap_finish_move(chan);
6102         if (err)
6103                 return err;
6104
6105         set_bit(CONN_SEND_FBIT, &chan->conn_state);
6106         l2cap_send_i_or_rr_or_rnr(chan);
6107
6108         if (event == L2CAP_EV_RECV_IFRAME)
6109                 return -EPROTO;
6110
6111         return l2cap_rx_state_recv(chan, control, NULL, event);
6112 }
6113
6114 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6115                                  struct l2cap_ctrl *control,
6116                                  struct sk_buff *skb, u8 event)
6117 {
6118         int err;
6119
6120         if (!control->final)
6121                 return -EPROTO;
6122
6123         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6124
6125         chan->rx_state = L2CAP_RX_STATE_RECV;
6126         l2cap_process_reqseq(chan, control->reqseq);
6127
6128         if (!skb_queue_empty(&chan->tx_q))
6129                 chan->tx_send_head = skb_peek(&chan->tx_q);
6130         else
6131                 chan->tx_send_head = NULL;
6132
6133         /* Rewind next_tx_seq to the point expected
6134          * by the receiver.
6135          */
6136         chan->next_tx_seq = control->reqseq;
6137         chan->unacked_frames = 0;
6138
6139         if (chan->hs_hcon)
6140                 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6141         else
6142                 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6143
6144         err = l2cap_resegment(chan);
6145
6146         if (!err)
6147                 err = l2cap_rx_state_recv(chan, control, skb, event);
6148
6149         return err;
6150 }
6151
6152 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6153 {
6154         /* Make sure reqseq is for a packet that has been sent but not acked */
6155         u16 unacked;
6156
6157         unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6158         return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6159 }
6160
6161 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6162                     struct sk_buff *skb, u8 event)
6163 {
6164         int err = 0;
6165
6166         BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6167                control, skb, event, chan->rx_state);
6168
6169         if (__valid_reqseq(chan, control->reqseq)) {
6170                 switch (chan->rx_state) {
6171                 case L2CAP_RX_STATE_RECV:
6172                         err = l2cap_rx_state_recv(chan, control, skb, event);
6173                         break;
6174                 case L2CAP_RX_STATE_SREJ_SENT:
6175                         err = l2cap_rx_state_srej_sent(chan, control, skb,
6176                                                        event);
6177                         break;
6178                 case L2CAP_RX_STATE_WAIT_P:
6179                         err = l2cap_rx_state_wait_p(chan, control, skb, event);
6180                         break;
6181                 case L2CAP_RX_STATE_WAIT_F:
6182                         err = l2cap_rx_state_wait_f(chan, control, skb, event);
6183                         break;
6184                 default:
6185                         /* shut it down */
6186                         break;
6187                 }
6188         } else {
6189                 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6190                        control->reqseq, chan->next_tx_seq,
6191                        chan->expected_ack_seq);
6192                 l2cap_send_disconn_req(chan, ECONNRESET);
6193         }
6194
6195         return err;
6196 }
6197
6198 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6199                            struct sk_buff *skb)
6200 {
6201         int err = 0;
6202
6203         BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6204                chan->rx_state);
6205
6206         if (l2cap_classify_txseq(chan, control->txseq) ==
6207             L2CAP_TXSEQ_EXPECTED) {
6208                 l2cap_pass_to_tx(chan, control);
6209
6210                 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6211                        __next_seq(chan, chan->buffer_seq));
6212
6213                 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6214
6215                 l2cap_reassemble_sdu(chan, skb, control);
6216         } else {
6217                 if (chan->sdu) {
6218                         kfree_skb(chan->sdu);
6219                         chan->sdu = NULL;
6220                 }
6221                 chan->sdu_last_frag = NULL;
6222                 chan->sdu_len = 0;
6223
6224                 if (skb) {
6225                         BT_DBG("Freeing %p", skb);
6226                         kfree_skb(skb);
6227                 }
6228         }
6229
6230         chan->last_acked_seq = control->txseq;
6231         chan->expected_tx_seq = __next_seq(chan, control->txseq);
6232
6233         return err;
6234 }
6235
6236 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6237 {
6238         struct l2cap_ctrl *control = &bt_cb(skb)->control;
6239         u16 len;
6240         u8 event;
6241
6242         __unpack_control(chan, skb);
6243
6244         len = skb->len;
6245
6246         /*
6247          * We can just drop the corrupted I-frame here.
6248          * Receiver will miss it and start proper recovery
6249          * procedures and ask for retransmission.
6250          */
6251         if (l2cap_check_fcs(chan, skb))
6252                 goto drop;
6253
6254         if (!control->sframe && control->sar == L2CAP_SAR_START)
6255                 len -= L2CAP_SDULEN_SIZE;
6256
6257         if (chan->fcs == L2CAP_FCS_CRC16)
6258                 len -= L2CAP_FCS_SIZE;
6259
6260         if (len > chan->mps) {
6261                 l2cap_send_disconn_req(chan, ECONNRESET);
6262                 goto drop;
6263         }
6264
6265         if (!control->sframe) {
6266                 int err;
6267
6268                 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6269                        control->sar, control->reqseq, control->final,
6270                        control->txseq);
6271
6272                 /* Validate F-bit - F=0 always valid, F=1 only
6273                  * valid in TX WAIT_F
6274                  */
6275                 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6276                         goto drop;
6277
6278                 if (chan->mode != L2CAP_MODE_STREAMING) {
6279                         event = L2CAP_EV_RECV_IFRAME;
6280                         err = l2cap_rx(chan, control, skb, event);
6281                 } else {
6282                         err = l2cap_stream_rx(chan, control, skb);
6283                 }
6284
6285                 if (err)
6286                         l2cap_send_disconn_req(chan, ECONNRESET);
6287         } else {
6288                 const u8 rx_func_to_event[4] = {
6289                         L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6290                         L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6291                 };
6292
6293                 /* Only I-frames are expected in streaming mode */
6294                 if (chan->mode == L2CAP_MODE_STREAMING)
6295                         goto drop;
6296
6297                 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6298                        control->reqseq, control->final, control->poll,
6299                        control->super);
6300
6301                 if (len != 0) {
6302                         BT_ERR("Trailing bytes: %d in sframe", len);
6303                         l2cap_send_disconn_req(chan, ECONNRESET);
6304                         goto drop;
6305                 }
6306
6307                 /* Validate F and P bits */
6308                 if (control->final && (control->poll ||
6309                                        chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6310                         goto drop;
6311
6312                 event = rx_func_to_event[control->super];
6313                 if (l2cap_rx(chan, control, skb, event))
6314                         l2cap_send_disconn_req(chan, ECONNRESET);
6315         }
6316
6317         return 0;
6318
6319 drop:
6320         kfree_skb(skb);
6321         return 0;
6322 }
6323
6324 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6325                                struct sk_buff *skb)
6326 {
6327         struct l2cap_chan *chan;
6328
6329         chan = l2cap_get_chan_by_scid(conn, cid);
6330         if (!chan) {
6331                 if (cid == L2CAP_CID_A2MP) {
6332                         chan = a2mp_channel_create(conn, skb);
6333                         if (!chan) {
6334                                 kfree_skb(skb);
6335                                 return;
6336                         }
6337
6338                         l2cap_chan_lock(chan);
6339                 } else {
6340                         BT_DBG("unknown cid 0x%4.4x", cid);
6341                         /* Drop packet and return */
6342                         kfree_skb(skb);
6343                         return;
6344                 }
6345         }
6346
6347         BT_DBG("chan %p, len %d", chan, skb->len);
6348
6349         if (chan->state != BT_CONNECTED)
6350                 goto drop;
6351
6352         switch (chan->mode) {
6353         case L2CAP_MODE_BASIC:
6354                 /* If socket recv buffers overflows we drop data here
6355                  * which is *bad* because L2CAP has to be reliable.
6356                  * But we don't have any other choice. L2CAP doesn't
6357                  * provide flow control mechanism. */
6358
6359                 if (chan->imtu < skb->len)
6360                         goto drop;
6361
6362                 if (!chan->ops->recv(chan, skb))
6363                         goto done;
6364                 break;
6365
6366         case L2CAP_MODE_ERTM:
6367         case L2CAP_MODE_STREAMING:
6368                 l2cap_data_rcv(chan, skb);
6369                 goto done;
6370
6371         default:
6372                 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6373                 break;
6374         }
6375
6376 drop:
6377         kfree_skb(skb);
6378
6379 done:
6380         l2cap_chan_unlock(chan);
6381 }
6382
6383 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6384                                   struct sk_buff *skb)
6385 {
6386         struct l2cap_chan *chan;
6387
6388         chan = l2cap_global_chan_by_psm(0, psm, conn->src, conn->dst);
6389         if (!chan)
6390                 goto drop;
6391
6392         BT_DBG("chan %p, len %d", chan, skb->len);
6393
6394         if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6395                 goto drop;
6396
6397         if (chan->imtu < skb->len)
6398                 goto drop;
6399
6400         if (!chan->ops->recv(chan, skb))
6401                 return;
6402
6403 drop:
6404         kfree_skb(skb);
6405 }
6406
6407 static void l2cap_att_channel(struct l2cap_conn *conn,
6408                               struct sk_buff *skb)
6409 {
6410         struct l2cap_chan *chan;
6411
6412         chan = l2cap_global_chan_by_scid(BT_CONNECTED, L2CAP_CID_ATT,
6413                                          conn->src, conn->dst);
6414         if (!chan)
6415                 goto drop;
6416
6417         BT_DBG("chan %p, len %d", chan, skb->len);
6418
6419         if (chan->imtu < skb->len)
6420                 goto drop;
6421
6422         if (!chan->ops->recv(chan, skb))
6423                 return;
6424
6425 drop:
6426         kfree_skb(skb);
6427 }
6428
6429 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6430 {
6431         struct l2cap_hdr *lh = (void *) skb->data;
6432         u16 cid, len;
6433         __le16 psm;
6434
6435         skb_pull(skb, L2CAP_HDR_SIZE);
6436         cid = __le16_to_cpu(lh->cid);
6437         len = __le16_to_cpu(lh->len);
6438
6439         if (len != skb->len) {
6440                 kfree_skb(skb);
6441                 return;
6442         }
6443
6444         BT_DBG("len %d, cid 0x%4.4x", len, cid);
6445
6446         switch (cid) {
6447         case L2CAP_CID_LE_SIGNALING:
6448                 l2cap_le_sig_channel(conn, skb);
6449                 break;
6450         case L2CAP_CID_SIGNALING:
6451                 l2cap_sig_channel(conn, skb);
6452                 break;
6453
6454         case L2CAP_CID_CONN_LESS:
6455                 psm = get_unaligned((__le16 *) skb->data);
6456                 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6457                 l2cap_conless_channel(conn, psm, skb);
6458                 break;
6459
6460         case L2CAP_CID_ATT:
6461                 l2cap_att_channel(conn, skb);
6462                 break;
6463
6464         case L2CAP_CID_SMP:
6465                 if (smp_sig_channel(conn, skb))
6466                         l2cap_conn_del(conn->hcon, EACCES);
6467                 break;
6468
6469         default:
6470                 l2cap_data_channel(conn, cid, skb);
6471                 break;
6472         }
6473 }
6474
6475 /* ---- L2CAP interface with lower layer (HCI) ---- */
6476
6477 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
6478 {
6479         int exact = 0, lm1 = 0, lm2 = 0;
6480         struct l2cap_chan *c;
6481
6482         BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
6483
6484         /* Find listening sockets and check their link_mode */
6485         read_lock(&chan_list_lock);
6486         list_for_each_entry(c, &chan_list, global_l) {
6487                 struct sock *sk = c->sk;
6488
6489                 if (c->state != BT_LISTEN)
6490                         continue;
6491
6492                 if (!bacmp(&bt_sk(sk)->src, &hdev->bdaddr)) {
6493                         lm1 |= HCI_LM_ACCEPT;
6494                         if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
6495                                 lm1 |= HCI_LM_MASTER;
6496                         exact++;
6497                 } else if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY)) {
6498                         lm2 |= HCI_LM_ACCEPT;
6499                         if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
6500                                 lm2 |= HCI_LM_MASTER;
6501                 }
6502         }
6503         read_unlock(&chan_list_lock);
6504
6505         return exact ? lm1 : lm2;
6506 }
6507
6508 void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
6509 {
6510         struct l2cap_conn *conn;
6511
6512         BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
6513
6514         if (!status) {
6515                 conn = l2cap_conn_add(hcon);
6516                 if (conn)
6517                         l2cap_conn_ready(conn);
6518         } else {
6519                 l2cap_conn_del(hcon, bt_to_errno(status));
6520         }
6521 }
6522
6523 int l2cap_disconn_ind(struct hci_conn *hcon)
6524 {
6525         struct l2cap_conn *conn = hcon->l2cap_data;
6526
6527         BT_DBG("hcon %p", hcon);
6528
6529         if (!conn)
6530                 return HCI_ERROR_REMOTE_USER_TERM;
6531         return conn->disc_reason;
6532 }
6533
6534 void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
6535 {
6536         BT_DBG("hcon %p reason %d", hcon, reason);
6537
6538         l2cap_conn_del(hcon, bt_to_errno(reason));
6539 }
6540
6541 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
6542 {
6543         if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
6544                 return;
6545
6546         if (encrypt == 0x00) {
6547                 if (chan->sec_level == BT_SECURITY_MEDIUM) {
6548                         __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
6549                 } else if (chan->sec_level == BT_SECURITY_HIGH)
6550                         l2cap_chan_close(chan, ECONNREFUSED);
6551         } else {
6552                 if (chan->sec_level == BT_SECURITY_MEDIUM)
6553                         __clear_chan_timer(chan);
6554         }
6555 }
6556
6557 int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
6558 {
6559         struct l2cap_conn *conn = hcon->l2cap_data;
6560         struct l2cap_chan *chan;
6561
6562         if (!conn)
6563                 return 0;
6564
6565         BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
6566
6567         if (hcon->type == LE_LINK) {
6568                 if (!status && encrypt)
6569                         smp_distribute_keys(conn, 0);
6570                 cancel_delayed_work(&conn->security_timer);
6571         }
6572
6573         mutex_lock(&conn->chan_lock);
6574
6575         list_for_each_entry(chan, &conn->chan_l, list) {
6576                 l2cap_chan_lock(chan);
6577
6578                 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
6579                        state_to_string(chan->state));
6580
6581                 if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
6582                         l2cap_chan_unlock(chan);
6583                         continue;
6584                 }
6585
6586                 if (chan->scid == L2CAP_CID_ATT) {
6587                         if (!status && encrypt) {
6588                                 chan->sec_level = hcon->sec_level;
6589                                 l2cap_chan_ready(chan);
6590                         }
6591
6592                         l2cap_chan_unlock(chan);
6593                         continue;
6594                 }
6595
6596                 if (!__l2cap_no_conn_pending(chan)) {
6597                         l2cap_chan_unlock(chan);
6598                         continue;
6599                 }
6600
6601                 if (!status && (chan->state == BT_CONNECTED ||
6602                                 chan->state == BT_CONFIG)) {
6603                         struct sock *sk = chan->sk;
6604
6605                         clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
6606                         sk->sk_state_change(sk);
6607
6608                         l2cap_check_encryption(chan, encrypt);
6609                         l2cap_chan_unlock(chan);
6610                         continue;
6611                 }
6612
6613                 if (chan->state == BT_CONNECT) {
6614                         if (!status) {
6615                                 l2cap_start_connection(chan);
6616                         } else {
6617                                 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
6618                         }
6619                 } else if (chan->state == BT_CONNECT2) {
6620                         struct sock *sk = chan->sk;
6621                         struct l2cap_conn_rsp rsp;
6622                         __u16 res, stat;
6623
6624                         lock_sock(sk);
6625
6626                         if (!status) {
6627                                 if (test_bit(BT_SK_DEFER_SETUP,
6628                                              &bt_sk(sk)->flags)) {
6629                                         res = L2CAP_CR_PEND;
6630                                         stat = L2CAP_CS_AUTHOR_PEND;
6631                                         chan->ops->defer(chan);
6632                                 } else {
6633                                         __l2cap_state_change(chan, BT_CONFIG);
6634                                         res = L2CAP_CR_SUCCESS;
6635                                         stat = L2CAP_CS_NO_INFO;
6636                                 }
6637                         } else {
6638                                 __l2cap_state_change(chan, BT_DISCONN);
6639                                 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
6640                                 res = L2CAP_CR_SEC_BLOCK;
6641                                 stat = L2CAP_CS_NO_INFO;
6642                         }
6643
6644                         release_sock(sk);
6645
6646                         rsp.scid   = cpu_to_le16(chan->dcid);
6647                         rsp.dcid   = cpu_to_le16(chan->scid);
6648                         rsp.result = cpu_to_le16(res);
6649                         rsp.status = cpu_to_le16(stat);
6650                         l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
6651                                        sizeof(rsp), &rsp);
6652
6653                         if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
6654                             res == L2CAP_CR_SUCCESS) {
6655                                 char buf[128];
6656                                 set_bit(CONF_REQ_SENT, &chan->conf_state);
6657                                 l2cap_send_cmd(conn, l2cap_get_ident(conn),
6658                                                L2CAP_CONF_REQ,
6659                                                l2cap_build_conf_req(chan, buf),
6660                                                buf);
6661                                 chan->num_conf_req++;
6662                         }
6663                 }
6664
6665                 l2cap_chan_unlock(chan);
6666         }
6667
6668         mutex_unlock(&conn->chan_lock);
6669
6670         return 0;
6671 }
6672
6673 int l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
6674 {
6675         struct l2cap_conn *conn = hcon->l2cap_data;
6676         struct l2cap_hdr *hdr;
6677         int len;
6678
6679         /* For AMP controller do not create l2cap conn */
6680         if (!conn && hcon->hdev->dev_type != HCI_BREDR)
6681                 goto drop;
6682
6683         if (!conn)
6684                 conn = l2cap_conn_add(hcon);
6685
6686         if (!conn)
6687                 goto drop;
6688
6689         BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
6690
6691         switch (flags) {
6692         case ACL_START:
6693         case ACL_START_NO_FLUSH:
6694         case ACL_COMPLETE:
6695                 if (conn->rx_len) {
6696                         BT_ERR("Unexpected start frame (len %d)", skb->len);
6697                         kfree_skb(conn->rx_skb);
6698                         conn->rx_skb = NULL;
6699                         conn->rx_len = 0;
6700                         l2cap_conn_unreliable(conn, ECOMM);
6701                 }
6702
6703                 /* Start fragment always begin with Basic L2CAP header */
6704                 if (skb->len < L2CAP_HDR_SIZE) {
6705                         BT_ERR("Frame is too short (len %d)", skb->len);
6706                         l2cap_conn_unreliable(conn, ECOMM);
6707                         goto drop;
6708                 }
6709
6710                 hdr = (struct l2cap_hdr *) skb->data;
6711                 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
6712
6713                 if (len == skb->len) {
6714                         /* Complete frame received */
6715                         l2cap_recv_frame(conn, skb);
6716                         return 0;
6717                 }
6718
6719                 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
6720
6721                 if (skb->len > len) {
6722                         BT_ERR("Frame is too long (len %d, expected len %d)",
6723                                skb->len, len);
6724                         l2cap_conn_unreliable(conn, ECOMM);
6725                         goto drop;
6726                 }
6727
6728                 /* Allocate skb for the complete frame (with header) */
6729                 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
6730                 if (!conn->rx_skb)
6731                         goto drop;
6732
6733                 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
6734                                           skb->len);
6735                 conn->rx_len = len - skb->len;
6736                 break;
6737
6738         case ACL_CONT:
6739                 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
6740
6741                 if (!conn->rx_len) {
6742                         BT_ERR("Unexpected continuation frame (len %d)", skb->len);
6743                         l2cap_conn_unreliable(conn, ECOMM);
6744                         goto drop;
6745                 }
6746
6747                 if (skb->len > conn->rx_len) {
6748                         BT_ERR("Fragment is too long (len %d, expected %d)",
6749                                skb->len, conn->rx_len);
6750                         kfree_skb(conn->rx_skb);
6751                         conn->rx_skb = NULL;
6752                         conn->rx_len = 0;
6753                         l2cap_conn_unreliable(conn, ECOMM);
6754                         goto drop;
6755                 }
6756
6757                 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
6758                                           skb->len);
6759                 conn->rx_len -= skb->len;
6760
6761                 if (!conn->rx_len) {
6762                         /* Complete frame received */
6763                         l2cap_recv_frame(conn, conn->rx_skb);
6764                         conn->rx_skb = NULL;
6765                 }
6766                 break;
6767         }
6768
6769 drop:
6770         kfree_skb(skb);
6771         return 0;
6772 }
6773
6774 static int l2cap_debugfs_show(struct seq_file *f, void *p)
6775 {
6776         struct l2cap_chan *c;
6777
6778         read_lock(&chan_list_lock);
6779
6780         list_for_each_entry(c, &chan_list, global_l) {
6781                 struct sock *sk = c->sk;
6782
6783                 seq_printf(f, "%pMR %pMR %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
6784                            &bt_sk(sk)->src, &bt_sk(sk)->dst,
6785                            c->state, __le16_to_cpu(c->psm),
6786                            c->scid, c->dcid, c->imtu, c->omtu,
6787                            c->sec_level, c->mode);
6788         }
6789
6790         read_unlock(&chan_list_lock);
6791
6792         return 0;
6793 }
6794
6795 static int l2cap_debugfs_open(struct inode *inode, struct file *file)
6796 {
6797         return single_open(file, l2cap_debugfs_show, inode->i_private);
6798 }
6799
6800 static const struct file_operations l2cap_debugfs_fops = {
6801         .open           = l2cap_debugfs_open,
6802         .read           = seq_read,
6803         .llseek         = seq_lseek,
6804         .release        = single_release,
6805 };
6806
6807 static struct dentry *l2cap_debugfs;
6808
6809 int __init l2cap_init(void)
6810 {
6811         int err;
6812
6813         err = l2cap_init_sockets();
6814         if (err < 0)
6815                 return err;
6816
6817         if (bt_debugfs) {
6818                 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
6819                                                     NULL, &l2cap_debugfs_fops);
6820                 if (!l2cap_debugfs)
6821                         BT_ERR("Failed to create L2CAP debug file");
6822         }
6823
6824         return 0;
6825 }
6826
6827 void l2cap_exit(void)
6828 {
6829         debugfs_remove(l2cap_debugfs);
6830         l2cap_cleanup_sockets();
6831 }
6832
6833 module_param(disable_ertm, bool, 0644);
6834 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");