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         /* Connectionless channel */
2456         if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2457                 skb = l2cap_create_connless_pdu(chan, msg, len, priority);
2458                 if (IS_ERR(skb))
2459                         return PTR_ERR(skb);
2460
2461                 l2cap_do_send(chan, skb);
2462                 return len;
2463         }
2464
2465         switch (chan->mode) {
2466         case L2CAP_MODE_BASIC:
2467                 /* Check outgoing MTU */
2468                 if (len > chan->omtu)
2469                         return -EMSGSIZE;
2470
2471                 /* Create a basic PDU */
2472                 skb = l2cap_create_basic_pdu(chan, msg, len, priority);
2473                 if (IS_ERR(skb))
2474                         return PTR_ERR(skb);
2475
2476                 l2cap_do_send(chan, skb);
2477                 err = len;
2478                 break;
2479
2480         case L2CAP_MODE_ERTM:
2481         case L2CAP_MODE_STREAMING:
2482                 /* Check outgoing MTU */
2483                 if (len > chan->omtu) {
2484                         err = -EMSGSIZE;
2485                         break;
2486                 }
2487
2488                 __skb_queue_head_init(&seg_queue);
2489
2490                 /* Do segmentation before calling in to the state machine,
2491                  * since it's possible to block while waiting for memory
2492                  * allocation.
2493                  */
2494                 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2495
2496                 /* The channel could have been closed while segmenting,
2497                  * check that it is still connected.
2498                  */
2499                 if (chan->state != BT_CONNECTED) {
2500                         __skb_queue_purge(&seg_queue);
2501                         err = -ENOTCONN;
2502                 }
2503
2504                 if (err)
2505                         break;
2506
2507                 if (chan->mode == L2CAP_MODE_ERTM)
2508                         l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2509                 else
2510                         l2cap_streaming_send(chan, &seg_queue);
2511
2512                 err = len;
2513
2514                 /* If the skbs were not queued for sending, they'll still be in
2515                  * seg_queue and need to be purged.
2516                  */
2517                 __skb_queue_purge(&seg_queue);
2518                 break;
2519
2520         default:
2521                 BT_DBG("bad state %1.1x", chan->mode);
2522                 err = -EBADFD;
2523         }
2524
2525         return err;
2526 }
2527
2528 static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2529 {
2530         struct l2cap_ctrl control;
2531         u16 seq;
2532
2533         BT_DBG("chan %p, txseq %u", chan, txseq);
2534
2535         memset(&control, 0, sizeof(control));
2536         control.sframe = 1;
2537         control.super = L2CAP_SUPER_SREJ;
2538
2539         for (seq = chan->expected_tx_seq; seq != txseq;
2540              seq = __next_seq(chan, seq)) {
2541                 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2542                         control.reqseq = seq;
2543                         l2cap_send_sframe(chan, &control);
2544                         l2cap_seq_list_append(&chan->srej_list, seq);
2545                 }
2546         }
2547
2548         chan->expected_tx_seq = __next_seq(chan, txseq);
2549 }
2550
2551 static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2552 {
2553         struct l2cap_ctrl control;
2554
2555         BT_DBG("chan %p", chan);
2556
2557         if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2558                 return;
2559
2560         memset(&control, 0, sizeof(control));
2561         control.sframe = 1;
2562         control.super = L2CAP_SUPER_SREJ;
2563         control.reqseq = chan->srej_list.tail;
2564         l2cap_send_sframe(chan, &control);
2565 }
2566
2567 static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2568 {
2569         struct l2cap_ctrl control;
2570         u16 initial_head;
2571         u16 seq;
2572
2573         BT_DBG("chan %p, txseq %u", chan, txseq);
2574
2575         memset(&control, 0, sizeof(control));
2576         control.sframe = 1;
2577         control.super = L2CAP_SUPER_SREJ;
2578
2579         /* Capture initial list head to allow only one pass through the list. */
2580         initial_head = chan->srej_list.head;
2581
2582         do {
2583                 seq = l2cap_seq_list_pop(&chan->srej_list);
2584                 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2585                         break;
2586
2587                 control.reqseq = seq;
2588                 l2cap_send_sframe(chan, &control);
2589                 l2cap_seq_list_append(&chan->srej_list, seq);
2590         } while (chan->srej_list.head != initial_head);
2591 }
2592
2593 static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2594 {
2595         struct sk_buff *acked_skb;
2596         u16 ackseq;
2597
2598         BT_DBG("chan %p, reqseq %u", chan, reqseq);
2599
2600         if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2601                 return;
2602
2603         BT_DBG("expected_ack_seq %u, unacked_frames %u",
2604                chan->expected_ack_seq, chan->unacked_frames);
2605
2606         for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2607              ackseq = __next_seq(chan, ackseq)) {
2608
2609                 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2610                 if (acked_skb) {
2611                         skb_unlink(acked_skb, &chan->tx_q);
2612                         kfree_skb(acked_skb);
2613                         chan->unacked_frames--;
2614                 }
2615         }
2616
2617         chan->expected_ack_seq = reqseq;
2618
2619         if (chan->unacked_frames == 0)
2620                 __clear_retrans_timer(chan);
2621
2622         BT_DBG("unacked_frames %u", chan->unacked_frames);
2623 }
2624
2625 static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2626 {
2627         BT_DBG("chan %p", chan);
2628
2629         chan->expected_tx_seq = chan->buffer_seq;
2630         l2cap_seq_list_clear(&chan->srej_list);
2631         skb_queue_purge(&chan->srej_q);
2632         chan->rx_state = L2CAP_RX_STATE_RECV;
2633 }
2634
2635 static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2636                                 struct l2cap_ctrl *control,
2637                                 struct sk_buff_head *skbs, u8 event)
2638 {
2639         BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2640                event);
2641
2642         switch (event) {
2643         case L2CAP_EV_DATA_REQUEST:
2644                 if (chan->tx_send_head == NULL)
2645                         chan->tx_send_head = skb_peek(skbs);
2646
2647                 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2648                 l2cap_ertm_send(chan);
2649                 break;
2650         case L2CAP_EV_LOCAL_BUSY_DETECTED:
2651                 BT_DBG("Enter LOCAL_BUSY");
2652                 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2653
2654                 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2655                         /* The SREJ_SENT state must be aborted if we are to
2656                          * enter the LOCAL_BUSY state.
2657                          */
2658                         l2cap_abort_rx_srej_sent(chan);
2659                 }
2660
2661                 l2cap_send_ack(chan);
2662
2663                 break;
2664         case L2CAP_EV_LOCAL_BUSY_CLEAR:
2665                 BT_DBG("Exit LOCAL_BUSY");
2666                 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2667
2668                 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2669                         struct l2cap_ctrl local_control;
2670
2671                         memset(&local_control, 0, sizeof(local_control));
2672                         local_control.sframe = 1;
2673                         local_control.super = L2CAP_SUPER_RR;
2674                         local_control.poll = 1;
2675                         local_control.reqseq = chan->buffer_seq;
2676                         l2cap_send_sframe(chan, &local_control);
2677
2678                         chan->retry_count = 1;
2679                         __set_monitor_timer(chan);
2680                         chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2681                 }
2682                 break;
2683         case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2684                 l2cap_process_reqseq(chan, control->reqseq);
2685                 break;
2686         case L2CAP_EV_EXPLICIT_POLL:
2687                 l2cap_send_rr_or_rnr(chan, 1);
2688                 chan->retry_count = 1;
2689                 __set_monitor_timer(chan);
2690                 __clear_ack_timer(chan);
2691                 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2692                 break;
2693         case L2CAP_EV_RETRANS_TO:
2694                 l2cap_send_rr_or_rnr(chan, 1);
2695                 chan->retry_count = 1;
2696                 __set_monitor_timer(chan);
2697                 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2698                 break;
2699         case L2CAP_EV_RECV_FBIT:
2700                 /* Nothing to process */
2701                 break;
2702         default:
2703                 break;
2704         }
2705 }
2706
2707 static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2708                                   struct l2cap_ctrl *control,
2709                                   struct sk_buff_head *skbs, u8 event)
2710 {
2711         BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2712                event);
2713
2714         switch (event) {
2715         case L2CAP_EV_DATA_REQUEST:
2716                 if (chan->tx_send_head == NULL)
2717                         chan->tx_send_head = skb_peek(skbs);
2718                 /* Queue data, but don't send. */
2719                 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2720                 break;
2721         case L2CAP_EV_LOCAL_BUSY_DETECTED:
2722                 BT_DBG("Enter LOCAL_BUSY");
2723                 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2724
2725                 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2726                         /* The SREJ_SENT state must be aborted if we are to
2727                          * enter the LOCAL_BUSY state.
2728                          */
2729                         l2cap_abort_rx_srej_sent(chan);
2730                 }
2731
2732                 l2cap_send_ack(chan);
2733
2734                 break;
2735         case L2CAP_EV_LOCAL_BUSY_CLEAR:
2736                 BT_DBG("Exit LOCAL_BUSY");
2737                 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2738
2739                 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2740                         struct l2cap_ctrl local_control;
2741                         memset(&local_control, 0, sizeof(local_control));
2742                         local_control.sframe = 1;
2743                         local_control.super = L2CAP_SUPER_RR;
2744                         local_control.poll = 1;
2745                         local_control.reqseq = chan->buffer_seq;
2746                         l2cap_send_sframe(chan, &local_control);
2747
2748                         chan->retry_count = 1;
2749                         __set_monitor_timer(chan);
2750                         chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2751                 }
2752                 break;
2753         case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2754                 l2cap_process_reqseq(chan, control->reqseq);
2755
2756                 /* Fall through */
2757
2758         case L2CAP_EV_RECV_FBIT:
2759                 if (control && control->final) {
2760                         __clear_monitor_timer(chan);
2761                         if (chan->unacked_frames > 0)
2762                                 __set_retrans_timer(chan);
2763                         chan->retry_count = 0;
2764                         chan->tx_state = L2CAP_TX_STATE_XMIT;
2765                         BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2766                 }
2767                 break;
2768         case L2CAP_EV_EXPLICIT_POLL:
2769                 /* Ignore */
2770                 break;
2771         case L2CAP_EV_MONITOR_TO:
2772                 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2773                         l2cap_send_rr_or_rnr(chan, 1);
2774                         __set_monitor_timer(chan);
2775                         chan->retry_count++;
2776                 } else {
2777                         l2cap_send_disconn_req(chan, ECONNABORTED);
2778                 }
2779                 break;
2780         default:
2781                 break;
2782         }
2783 }
2784
2785 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2786                      struct sk_buff_head *skbs, u8 event)
2787 {
2788         BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2789                chan, control, skbs, event, chan->tx_state);
2790
2791         switch (chan->tx_state) {
2792         case L2CAP_TX_STATE_XMIT:
2793                 l2cap_tx_state_xmit(chan, control, skbs, event);
2794                 break;
2795         case L2CAP_TX_STATE_WAIT_F:
2796                 l2cap_tx_state_wait_f(chan, control, skbs, event);
2797                 break;
2798         default:
2799                 /* Ignore event */
2800                 break;
2801         }
2802 }
2803
2804 static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2805                              struct l2cap_ctrl *control)
2806 {
2807         BT_DBG("chan %p, control %p", chan, control);
2808         l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2809 }
2810
2811 static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2812                                   struct l2cap_ctrl *control)
2813 {
2814         BT_DBG("chan %p, control %p", chan, control);
2815         l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2816 }
2817
2818 /* Copy frame to all raw sockets on that connection */
2819 static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2820 {
2821         struct sk_buff *nskb;
2822         struct l2cap_chan *chan;
2823
2824         BT_DBG("conn %p", conn);
2825
2826         mutex_lock(&conn->chan_lock);
2827
2828         list_for_each_entry(chan, &conn->chan_l, list) {
2829                 struct sock *sk = chan->sk;
2830                 if (chan->chan_type != L2CAP_CHAN_RAW)
2831                         continue;
2832
2833                 /* Don't send frame to the socket it came from */
2834                 if (skb->sk == sk)
2835                         continue;
2836                 nskb = skb_clone(skb, GFP_KERNEL);
2837                 if (!nskb)
2838                         continue;
2839
2840                 if (chan->ops->recv(chan, nskb))
2841                         kfree_skb(nskb);
2842         }
2843
2844         mutex_unlock(&conn->chan_lock);
2845 }
2846
2847 /* ---- L2CAP signalling commands ---- */
2848 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2849                                        u8 ident, u16 dlen, void *data)
2850 {
2851         struct sk_buff *skb, **frag;
2852         struct l2cap_cmd_hdr *cmd;
2853         struct l2cap_hdr *lh;
2854         int len, count;
2855
2856         BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2857                conn, code, ident, dlen);
2858
2859         if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2860                 return NULL;
2861
2862         len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2863         count = min_t(unsigned int, conn->mtu, len);
2864
2865         skb = bt_skb_alloc(count, GFP_KERNEL);
2866         if (!skb)
2867                 return NULL;
2868
2869         lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2870         lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2871
2872         if (conn->hcon->type == LE_LINK)
2873                 lh->cid = __constant_cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2874         else
2875                 lh->cid = __constant_cpu_to_le16(L2CAP_CID_SIGNALING);
2876
2877         cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2878         cmd->code  = code;
2879         cmd->ident = ident;
2880         cmd->len   = cpu_to_le16(dlen);
2881
2882         if (dlen) {
2883                 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2884                 memcpy(skb_put(skb, count), data, count);
2885                 data += count;
2886         }
2887
2888         len -= skb->len;
2889
2890         /* Continuation fragments (no L2CAP header) */
2891         frag = &skb_shinfo(skb)->frag_list;
2892         while (len) {
2893                 count = min_t(unsigned int, conn->mtu, len);
2894
2895                 *frag = bt_skb_alloc(count, GFP_KERNEL);
2896                 if (!*frag)
2897                         goto fail;
2898
2899                 memcpy(skb_put(*frag, count), data, count);
2900
2901                 len  -= count;
2902                 data += count;
2903
2904                 frag = &(*frag)->next;
2905         }
2906
2907         return skb;
2908
2909 fail:
2910         kfree_skb(skb);
2911         return NULL;
2912 }
2913
2914 static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2915                                      unsigned long *val)
2916 {
2917         struct l2cap_conf_opt *opt = *ptr;
2918         int len;
2919
2920         len = L2CAP_CONF_OPT_SIZE + opt->len;
2921         *ptr += len;
2922
2923         *type = opt->type;
2924         *olen = opt->len;
2925
2926         switch (opt->len) {
2927         case 1:
2928                 *val = *((u8 *) opt->val);
2929                 break;
2930
2931         case 2:
2932                 *val = get_unaligned_le16(opt->val);
2933                 break;
2934
2935         case 4:
2936                 *val = get_unaligned_le32(opt->val);
2937                 break;
2938
2939         default:
2940                 *val = (unsigned long) opt->val;
2941                 break;
2942         }
2943
2944         BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2945         return len;
2946 }
2947
2948 static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2949 {
2950         struct l2cap_conf_opt *opt = *ptr;
2951
2952         BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2953
2954         opt->type = type;
2955         opt->len  = len;
2956
2957         switch (len) {
2958         case 1:
2959                 *((u8 *) opt->val)  = val;
2960                 break;
2961
2962         case 2:
2963                 put_unaligned_le16(val, opt->val);
2964                 break;
2965
2966         case 4:
2967                 put_unaligned_le32(val, opt->val);
2968                 break;
2969
2970         default:
2971                 memcpy(opt->val, (void *) val, len);
2972                 break;
2973         }
2974
2975         *ptr += L2CAP_CONF_OPT_SIZE + len;
2976 }
2977
2978 static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
2979 {
2980         struct l2cap_conf_efs efs;
2981
2982         switch (chan->mode) {
2983         case L2CAP_MODE_ERTM:
2984                 efs.id          = chan->local_id;
2985                 efs.stype       = chan->local_stype;
2986                 efs.msdu        = cpu_to_le16(chan->local_msdu);
2987                 efs.sdu_itime   = cpu_to_le32(chan->local_sdu_itime);
2988                 efs.acc_lat     = __constant_cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
2989                 efs.flush_to    = __constant_cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
2990                 break;
2991
2992         case L2CAP_MODE_STREAMING:
2993                 efs.id          = 1;
2994                 efs.stype       = L2CAP_SERV_BESTEFFORT;
2995                 efs.msdu        = cpu_to_le16(chan->local_msdu);
2996                 efs.sdu_itime   = cpu_to_le32(chan->local_sdu_itime);
2997                 efs.acc_lat     = 0;
2998                 efs.flush_to    = 0;
2999                 break;
3000
3001         default:
3002                 return;
3003         }
3004
3005         l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3006                            (unsigned long) &efs);
3007 }
3008
3009 static void l2cap_ack_timeout(struct work_struct *work)
3010 {
3011         struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3012                                                ack_timer.work);
3013         u16 frames_to_ack;
3014
3015         BT_DBG("chan %p", chan);
3016
3017         l2cap_chan_lock(chan);
3018
3019         frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3020                                      chan->last_acked_seq);
3021
3022         if (frames_to_ack)
3023                 l2cap_send_rr_or_rnr(chan, 0);
3024
3025         l2cap_chan_unlock(chan);
3026         l2cap_chan_put(chan);
3027 }
3028
3029 int l2cap_ertm_init(struct l2cap_chan *chan)
3030 {
3031         int err;
3032
3033         chan->next_tx_seq = 0;
3034         chan->expected_tx_seq = 0;
3035         chan->expected_ack_seq = 0;
3036         chan->unacked_frames = 0;
3037         chan->buffer_seq = 0;
3038         chan->frames_sent = 0;
3039         chan->last_acked_seq = 0;
3040         chan->sdu = NULL;
3041         chan->sdu_last_frag = NULL;
3042         chan->sdu_len = 0;
3043
3044         skb_queue_head_init(&chan->tx_q);
3045
3046         chan->local_amp_id = 0;
3047         chan->move_id = 0;
3048         chan->move_state = L2CAP_MOVE_STABLE;
3049         chan->move_role = L2CAP_MOVE_ROLE_NONE;
3050
3051         if (chan->mode != L2CAP_MODE_ERTM)
3052                 return 0;
3053
3054         chan->rx_state = L2CAP_RX_STATE_RECV;
3055         chan->tx_state = L2CAP_TX_STATE_XMIT;
3056
3057         INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3058         INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3059         INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3060
3061         skb_queue_head_init(&chan->srej_q);
3062
3063         err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3064         if (err < 0)
3065                 return err;
3066
3067         err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3068         if (err < 0)
3069                 l2cap_seq_list_free(&chan->srej_list);
3070
3071         return err;
3072 }
3073
3074 static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3075 {
3076         switch (mode) {
3077         case L2CAP_MODE_STREAMING:
3078         case L2CAP_MODE_ERTM:
3079                 if (l2cap_mode_supported(mode, remote_feat_mask))
3080                         return mode;
3081                 /* fall through */
3082         default:
3083                 return L2CAP_MODE_BASIC;
3084         }
3085 }
3086
3087 static inline bool __l2cap_ews_supported(struct l2cap_chan *chan)
3088 {
3089         return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_WINDOW;
3090 }
3091
3092 static inline bool __l2cap_efs_supported(struct l2cap_chan *chan)
3093 {
3094         return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_FLOW;
3095 }
3096
3097 static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3098                                       struct l2cap_conf_rfc *rfc)
3099 {
3100         if (chan->local_amp_id && chan->hs_hcon) {
3101                 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3102
3103                 /* Class 1 devices have must have ERTM timeouts
3104                  * exceeding the Link Supervision Timeout.  The
3105                  * default Link Supervision Timeout for AMP
3106                  * controllers is 10 seconds.
3107                  *
3108                  * Class 1 devices use 0xffffffff for their
3109                  * best-effort flush timeout, so the clamping logic
3110                  * will result in a timeout that meets the above
3111                  * requirement.  ERTM timeouts are 16-bit values, so
3112                  * the maximum timeout is 65.535 seconds.
3113                  */
3114
3115                 /* Convert timeout to milliseconds and round */
3116                 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3117
3118                 /* This is the recommended formula for class 2 devices
3119                  * that start ERTM timers when packets are sent to the
3120                  * controller.
3121                  */
3122                 ertm_to = 3 * ertm_to + 500;
3123
3124                 if (ertm_to > 0xffff)
3125                         ertm_to = 0xffff;
3126
3127                 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3128                 rfc->monitor_timeout = rfc->retrans_timeout;
3129         } else {
3130                 rfc->retrans_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3131                 rfc->monitor_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3132         }
3133 }
3134
3135 static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3136 {
3137         if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3138             __l2cap_ews_supported(chan)) {
3139                 /* use extended control field */
3140                 set_bit(FLAG_EXT_CTRL, &chan->flags);
3141                 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3142         } else {
3143                 chan->tx_win = min_t(u16, chan->tx_win,
3144                                      L2CAP_DEFAULT_TX_WINDOW);
3145                 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3146         }
3147         chan->ack_win = chan->tx_win;
3148 }
3149
3150 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
3151 {
3152         struct l2cap_conf_req *req = data;
3153         struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3154         void *ptr = req->data;
3155         u16 size;
3156
3157         BT_DBG("chan %p", chan);
3158
3159         if (chan->num_conf_req || chan->num_conf_rsp)
3160                 goto done;
3161
3162         switch (chan->mode) {
3163         case L2CAP_MODE_STREAMING:
3164         case L2CAP_MODE_ERTM:
3165                 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3166                         break;
3167
3168                 if (__l2cap_efs_supported(chan))
3169                         set_bit(FLAG_EFS_ENABLE, &chan->flags);
3170
3171                 /* fall through */
3172         default:
3173                 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3174                 break;
3175         }
3176
3177 done:
3178         if (chan->imtu != L2CAP_DEFAULT_MTU)
3179                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3180
3181         switch (chan->mode) {
3182         case L2CAP_MODE_BASIC:
3183                 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3184                     !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3185                         break;
3186
3187                 rfc.mode            = L2CAP_MODE_BASIC;
3188                 rfc.txwin_size      = 0;
3189                 rfc.max_transmit    = 0;
3190                 rfc.retrans_timeout = 0;
3191                 rfc.monitor_timeout = 0;
3192                 rfc.max_pdu_size    = 0;
3193
3194                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3195                                    (unsigned long) &rfc);
3196                 break;
3197
3198         case L2CAP_MODE_ERTM:
3199                 rfc.mode            = L2CAP_MODE_ERTM;
3200                 rfc.max_transmit    = chan->max_tx;
3201
3202                 __l2cap_set_ertm_timeouts(chan, &rfc);
3203
3204                 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3205                              L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3206                              L2CAP_FCS_SIZE);
3207                 rfc.max_pdu_size = cpu_to_le16(size);
3208
3209                 l2cap_txwin_setup(chan);
3210
3211                 rfc.txwin_size = min_t(u16, chan->tx_win,
3212                                        L2CAP_DEFAULT_TX_WINDOW);
3213
3214                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3215                                    (unsigned long) &rfc);
3216
3217                 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3218                         l2cap_add_opt_efs(&ptr, chan);
3219
3220                 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3221                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3222                                            chan->tx_win);
3223
3224                 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3225                         if (chan->fcs == L2CAP_FCS_NONE ||
3226                             test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3227                                 chan->fcs = L2CAP_FCS_NONE;
3228                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3229                                                    chan->fcs);
3230                         }
3231                 break;
3232
3233         case L2CAP_MODE_STREAMING:
3234                 l2cap_txwin_setup(chan);
3235                 rfc.mode            = L2CAP_MODE_STREAMING;
3236                 rfc.txwin_size      = 0;
3237                 rfc.max_transmit    = 0;
3238                 rfc.retrans_timeout = 0;
3239                 rfc.monitor_timeout = 0;
3240
3241                 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3242                              L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3243                              L2CAP_FCS_SIZE);
3244                 rfc.max_pdu_size = cpu_to_le16(size);
3245
3246                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3247                                    (unsigned long) &rfc);
3248
3249                 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3250                         l2cap_add_opt_efs(&ptr, chan);
3251
3252                 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3253                         if (chan->fcs == L2CAP_FCS_NONE ||
3254                             test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3255                                 chan->fcs = L2CAP_FCS_NONE;
3256                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3257                                                    chan->fcs);
3258                         }
3259                 break;
3260         }
3261
3262         req->dcid  = cpu_to_le16(chan->dcid);
3263         req->flags = __constant_cpu_to_le16(0);
3264
3265         return ptr - data;
3266 }
3267
3268 static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3269 {
3270         struct l2cap_conf_rsp *rsp = data;
3271         void *ptr = rsp->data;
3272         void *req = chan->conf_req;
3273         int len = chan->conf_len;
3274         int type, hint, olen;
3275         unsigned long val;
3276         struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3277         struct l2cap_conf_efs efs;
3278         u8 remote_efs = 0;
3279         u16 mtu = L2CAP_DEFAULT_MTU;
3280         u16 result = L2CAP_CONF_SUCCESS;
3281         u16 size;
3282
3283         BT_DBG("chan %p", chan);
3284
3285         while (len >= L2CAP_CONF_OPT_SIZE) {
3286                 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3287
3288                 hint  = type & L2CAP_CONF_HINT;
3289                 type &= L2CAP_CONF_MASK;
3290
3291                 switch (type) {
3292                 case L2CAP_CONF_MTU:
3293                         mtu = val;
3294                         break;
3295
3296                 case L2CAP_CONF_FLUSH_TO:
3297                         chan->flush_to = val;
3298                         break;
3299
3300                 case L2CAP_CONF_QOS:
3301                         break;
3302
3303                 case L2CAP_CONF_RFC:
3304                         if (olen == sizeof(rfc))
3305                                 memcpy(&rfc, (void *) val, olen);
3306                         break;
3307
3308                 case L2CAP_CONF_FCS:
3309                         if (val == L2CAP_FCS_NONE)
3310                                 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3311                         break;
3312
3313                 case L2CAP_CONF_EFS:
3314                         remote_efs = 1;
3315                         if (olen == sizeof(efs))
3316                                 memcpy(&efs, (void *) val, olen);
3317                         break;
3318
3319                 case L2CAP_CONF_EWS:
3320                         if (!enable_hs)
3321                                 return -ECONNREFUSED;
3322
3323                         set_bit(FLAG_EXT_CTRL, &chan->flags);
3324                         set_bit(CONF_EWS_RECV, &chan->conf_state);
3325                         chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3326                         chan->remote_tx_win = val;
3327                         break;
3328
3329                 default:
3330                         if (hint)
3331                                 break;
3332
3333                         result = L2CAP_CONF_UNKNOWN;
3334                         *((u8 *) ptr++) = type;
3335                         break;
3336                 }
3337         }
3338
3339         if (chan->num_conf_rsp || chan->num_conf_req > 1)
3340                 goto done;
3341
3342         switch (chan->mode) {
3343         case L2CAP_MODE_STREAMING:
3344         case L2CAP_MODE_ERTM:
3345                 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3346                         chan->mode = l2cap_select_mode(rfc.mode,
3347                                                        chan->conn->feat_mask);
3348                         break;
3349                 }
3350
3351                 if (remote_efs) {
3352                         if (__l2cap_efs_supported(chan))
3353                                 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3354                         else
3355                                 return -ECONNREFUSED;
3356                 }
3357
3358                 if (chan->mode != rfc.mode)
3359                         return -ECONNREFUSED;
3360
3361                 break;
3362         }
3363
3364 done:
3365         if (chan->mode != rfc.mode) {
3366                 result = L2CAP_CONF_UNACCEPT;
3367                 rfc.mode = chan->mode;
3368
3369                 if (chan->num_conf_rsp == 1)
3370                         return -ECONNREFUSED;
3371
3372                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3373                                    (unsigned long) &rfc);
3374         }
3375
3376         if (result == L2CAP_CONF_SUCCESS) {
3377                 /* Configure output options and let the other side know
3378                  * which ones we don't like. */
3379
3380                 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3381                         result = L2CAP_CONF_UNACCEPT;
3382                 else {
3383                         chan->omtu = mtu;
3384                         set_bit(CONF_MTU_DONE, &chan->conf_state);
3385                 }
3386                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3387
3388                 if (remote_efs) {
3389                         if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3390                             efs.stype != L2CAP_SERV_NOTRAFIC &&
3391                             efs.stype != chan->local_stype) {
3392
3393                                 result = L2CAP_CONF_UNACCEPT;
3394
3395                                 if (chan->num_conf_req >= 1)
3396                                         return -ECONNREFUSED;
3397
3398                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3399                                                    sizeof(efs),
3400                                                    (unsigned long) &efs);
3401                         } else {
3402                                 /* Send PENDING Conf Rsp */
3403                                 result = L2CAP_CONF_PENDING;
3404                                 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3405                         }
3406                 }
3407
3408                 switch (rfc.mode) {
3409                 case L2CAP_MODE_BASIC:
3410                         chan->fcs = L2CAP_FCS_NONE;
3411                         set_bit(CONF_MODE_DONE, &chan->conf_state);
3412                         break;
3413
3414                 case L2CAP_MODE_ERTM:
3415                         if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3416                                 chan->remote_tx_win = rfc.txwin_size;
3417                         else
3418                                 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3419
3420                         chan->remote_max_tx = rfc.max_transmit;
3421
3422                         size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3423                                      chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3424                                      L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3425                         rfc.max_pdu_size = cpu_to_le16(size);
3426                         chan->remote_mps = size;
3427
3428                         __l2cap_set_ertm_timeouts(chan, &rfc);
3429
3430                         set_bit(CONF_MODE_DONE, &chan->conf_state);
3431
3432                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3433                                            sizeof(rfc), (unsigned long) &rfc);
3434
3435                         if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3436                                 chan->remote_id = efs.id;
3437                                 chan->remote_stype = efs.stype;
3438                                 chan->remote_msdu = le16_to_cpu(efs.msdu);
3439                                 chan->remote_flush_to =
3440                                         le32_to_cpu(efs.flush_to);
3441                                 chan->remote_acc_lat =
3442                                         le32_to_cpu(efs.acc_lat);
3443                                 chan->remote_sdu_itime =
3444                                         le32_to_cpu(efs.sdu_itime);
3445                                 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3446                                                    sizeof(efs),
3447                                                    (unsigned long) &efs);
3448                         }
3449                         break;
3450
3451                 case L2CAP_MODE_STREAMING:
3452                         size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3453                                      chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3454                                      L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3455                         rfc.max_pdu_size = cpu_to_le16(size);
3456                         chan->remote_mps = size;
3457
3458                         set_bit(CONF_MODE_DONE, &chan->conf_state);
3459
3460                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3461                                            (unsigned long) &rfc);
3462
3463                         break;
3464
3465                 default:
3466                         result = L2CAP_CONF_UNACCEPT;
3467
3468                         memset(&rfc, 0, sizeof(rfc));
3469                         rfc.mode = chan->mode;
3470                 }
3471
3472                 if (result == L2CAP_CONF_SUCCESS)
3473                         set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3474         }
3475         rsp->scid   = cpu_to_le16(chan->dcid);
3476         rsp->result = cpu_to_le16(result);
3477         rsp->flags  = __constant_cpu_to_le16(0);
3478
3479         return ptr - data;
3480 }
3481
3482 static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3483                                 void *data, u16 *result)
3484 {
3485         struct l2cap_conf_req *req = data;
3486         void *ptr = req->data;
3487         int type, olen;
3488         unsigned long val;
3489         struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3490         struct l2cap_conf_efs efs;
3491
3492         BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3493
3494         while (len >= L2CAP_CONF_OPT_SIZE) {
3495                 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3496
3497                 switch (type) {
3498                 case L2CAP_CONF_MTU:
3499                         if (val < L2CAP_DEFAULT_MIN_MTU) {
3500                                 *result = L2CAP_CONF_UNACCEPT;
3501                                 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3502                         } else
3503                                 chan->imtu = val;
3504                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3505                         break;
3506
3507                 case L2CAP_CONF_FLUSH_TO:
3508                         chan->flush_to = val;
3509                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3510                                            2, chan->flush_to);
3511                         break;
3512
3513                 case L2CAP_CONF_RFC:
3514                         if (olen == sizeof(rfc))
3515                                 memcpy(&rfc, (void *)val, olen);
3516
3517                         if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3518                             rfc.mode != chan->mode)
3519                                 return -ECONNREFUSED;
3520
3521                         chan->fcs = 0;
3522
3523                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3524                                            sizeof(rfc), (unsigned long) &rfc);
3525                         break;
3526
3527                 case L2CAP_CONF_EWS:
3528                         chan->ack_win = min_t(u16, val, chan->ack_win);
3529                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3530                                            chan->tx_win);
3531                         break;
3532
3533                 case L2CAP_CONF_EFS:
3534                         if (olen == sizeof(efs))
3535                                 memcpy(&efs, (void *)val, olen);
3536
3537                         if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3538                             efs.stype != L2CAP_SERV_NOTRAFIC &&
3539                             efs.stype != chan->local_stype)
3540                                 return -ECONNREFUSED;
3541
3542                         l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3543                                            (unsigned long) &efs);
3544                         break;
3545
3546                 case L2CAP_CONF_FCS:
3547                         if (*result == L2CAP_CONF_PENDING)
3548                                 if (val == L2CAP_FCS_NONE)
3549                                         set_bit(CONF_RECV_NO_FCS,
3550                                                 &chan->conf_state);
3551                         break;
3552                 }
3553         }
3554
3555         if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3556                 return -ECONNREFUSED;
3557
3558         chan->mode = rfc.mode;
3559
3560         if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3561                 switch (rfc.mode) {
3562                 case L2CAP_MODE_ERTM:
3563                         chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3564                         chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3565                         chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3566                         if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3567                                 chan->ack_win = min_t(u16, chan->ack_win,
3568                                                       rfc.txwin_size);
3569
3570                         if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3571                                 chan->local_msdu = le16_to_cpu(efs.msdu);
3572                                 chan->local_sdu_itime =
3573                                         le32_to_cpu(efs.sdu_itime);
3574                                 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3575                                 chan->local_flush_to =
3576                                         le32_to_cpu(efs.flush_to);
3577                         }
3578                         break;
3579
3580                 case L2CAP_MODE_STREAMING:
3581                         chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3582                 }
3583         }
3584
3585         req->dcid   = cpu_to_le16(chan->dcid);
3586         req->flags  = __constant_cpu_to_le16(0);
3587
3588         return ptr - data;
3589 }
3590
3591 static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3592                                 u16 result, u16 flags)
3593 {
3594         struct l2cap_conf_rsp *rsp = data;
3595         void *ptr = rsp->data;
3596
3597         BT_DBG("chan %p", chan);
3598
3599         rsp->scid   = cpu_to_le16(chan->dcid);
3600         rsp->result = cpu_to_le16(result);
3601         rsp->flags  = cpu_to_le16(flags);
3602
3603         return ptr - data;
3604 }
3605
3606 void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3607 {
3608         struct l2cap_conn_rsp rsp;
3609         struct l2cap_conn *conn = chan->conn;
3610         u8 buf[128];
3611         u8 rsp_code;
3612
3613         rsp.scid   = cpu_to_le16(chan->dcid);
3614         rsp.dcid   = cpu_to_le16(chan->scid);
3615         rsp.result = __constant_cpu_to_le16(L2CAP_CR_SUCCESS);
3616         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
3617
3618         if (chan->hs_hcon)
3619                 rsp_code = L2CAP_CREATE_CHAN_RSP;
3620         else
3621                 rsp_code = L2CAP_CONN_RSP;
3622
3623         BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3624
3625         l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3626
3627         if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3628                 return;
3629
3630         l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3631                        l2cap_build_conf_req(chan, buf), buf);
3632         chan->num_conf_req++;
3633 }
3634
3635 static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3636 {
3637         int type, olen;
3638         unsigned long val;
3639         /* Use sane default values in case a misbehaving remote device
3640          * did not send an RFC or extended window size option.
3641          */
3642         u16 txwin_ext = chan->ack_win;
3643         struct l2cap_conf_rfc rfc = {
3644                 .mode = chan->mode,
3645                 .retrans_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3646                 .monitor_timeout = __constant_cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3647                 .max_pdu_size = cpu_to_le16(chan->imtu),
3648                 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3649         };
3650
3651         BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3652
3653         if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3654                 return;
3655
3656         while (len >= L2CAP_CONF_OPT_SIZE) {
3657                 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3658
3659                 switch (type) {
3660                 case L2CAP_CONF_RFC:
3661                         if (olen == sizeof(rfc))
3662                                 memcpy(&rfc, (void *)val, olen);
3663                         break;
3664                 case L2CAP_CONF_EWS:
3665                         txwin_ext = val;
3666                         break;
3667                 }
3668         }
3669
3670         switch (rfc.mode) {
3671         case L2CAP_MODE_ERTM:
3672                 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3673                 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3674                 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3675                 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3676                         chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3677                 else
3678                         chan->ack_win = min_t(u16, chan->ack_win,
3679                                               rfc.txwin_size);
3680                 break;
3681         case L2CAP_MODE_STREAMING:
3682                 chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3683         }
3684 }
3685
3686 static inline int l2cap_command_rej(struct l2cap_conn *conn,
3687                                     struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3688                                     u8 *data)
3689 {
3690         struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3691
3692         if (cmd_len < sizeof(*rej))
3693                 return -EPROTO;
3694
3695         if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3696                 return 0;
3697
3698         if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3699             cmd->ident == conn->info_ident) {
3700                 cancel_delayed_work(&conn->info_timer);
3701
3702                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3703                 conn->info_ident = 0;
3704
3705                 l2cap_conn_start(conn);
3706         }
3707
3708         return 0;
3709 }
3710
3711 static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3712                                         struct l2cap_cmd_hdr *cmd,
3713                                         u8 *data, u8 rsp_code, u8 amp_id)
3714 {
3715         struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3716         struct l2cap_conn_rsp rsp;
3717         struct l2cap_chan *chan = NULL, *pchan;
3718         struct sock *parent, *sk = NULL;
3719         int result, status = L2CAP_CS_NO_INFO;
3720
3721         u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3722         __le16 psm = req->psm;
3723
3724         BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3725
3726         /* Check if we have socket listening on psm */
3727         pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, conn->src, conn->dst);
3728         if (!pchan) {
3729                 result = L2CAP_CR_BAD_PSM;
3730                 goto sendresp;
3731         }
3732
3733         parent = pchan->sk;
3734
3735         mutex_lock(&conn->chan_lock);
3736         lock_sock(parent);
3737
3738         /* Check if the ACL is secure enough (if not SDP) */
3739         if (psm != __constant_cpu_to_le16(L2CAP_PSM_SDP) &&
3740             !hci_conn_check_link_mode(conn->hcon)) {
3741                 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3742                 result = L2CAP_CR_SEC_BLOCK;
3743                 goto response;
3744         }
3745
3746         result = L2CAP_CR_NO_MEM;
3747
3748         /* Check if we already have channel with that dcid */
3749         if (__l2cap_get_chan_by_dcid(conn, scid))
3750                 goto response;
3751
3752         chan = pchan->ops->new_connection(pchan);
3753         if (!chan)
3754                 goto response;
3755
3756         sk = chan->sk;
3757
3758         /* For certain devices (ex: HID mouse), support for authentication,
3759          * pairing and bonding is optional. For such devices, inorder to avoid
3760          * the ACL alive for too long after L2CAP disconnection, reset the ACL
3761          * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3762          */
3763         conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3764
3765         bacpy(&bt_sk(sk)->src, conn->src);
3766         bacpy(&bt_sk(sk)->dst, conn->dst);
3767         chan->psm  = psm;
3768         chan->dcid = scid;
3769         chan->local_amp_id = amp_id;
3770
3771         __l2cap_chan_add(conn, chan);
3772
3773         dcid = chan->scid;
3774
3775         __set_chan_timer(chan, sk->sk_sndtimeo);
3776
3777         chan->ident = cmd->ident;
3778
3779         if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3780                 if (l2cap_chan_check_security(chan)) {
3781                         if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
3782                                 __l2cap_state_change(chan, BT_CONNECT2);
3783                                 result = L2CAP_CR_PEND;
3784                                 status = L2CAP_CS_AUTHOR_PEND;
3785                                 chan->ops->defer(chan);
3786                         } else {
3787                                 /* Force pending result for AMP controllers.
3788                                  * The connection will succeed after the
3789                                  * physical link is up.
3790                                  */
3791                                 if (amp_id) {
3792                                         __l2cap_state_change(chan, BT_CONNECT2);
3793                                         result = L2CAP_CR_PEND;
3794                                 } else {
3795                                         __l2cap_state_change(chan, BT_CONFIG);
3796                                         result = L2CAP_CR_SUCCESS;
3797                                 }
3798                                 status = L2CAP_CS_NO_INFO;
3799                         }
3800                 } else {
3801                         __l2cap_state_change(chan, BT_CONNECT2);
3802                         result = L2CAP_CR_PEND;
3803                         status = L2CAP_CS_AUTHEN_PEND;
3804                 }
3805         } else {
3806                 __l2cap_state_change(chan, BT_CONNECT2);
3807                 result = L2CAP_CR_PEND;
3808                 status = L2CAP_CS_NO_INFO;
3809         }
3810
3811 response:
3812         release_sock(parent);
3813         mutex_unlock(&conn->chan_lock);
3814
3815 sendresp:
3816         rsp.scid   = cpu_to_le16(scid);
3817         rsp.dcid   = cpu_to_le16(dcid);
3818         rsp.result = cpu_to_le16(result);
3819         rsp.status = cpu_to_le16(status);
3820         l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3821
3822         if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3823                 struct l2cap_info_req info;
3824                 info.type = __constant_cpu_to_le16(L2CAP_IT_FEAT_MASK);
3825
3826                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3827                 conn->info_ident = l2cap_get_ident(conn);
3828
3829                 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3830
3831                 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3832                                sizeof(info), &info);
3833         }
3834
3835         if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3836             result == L2CAP_CR_SUCCESS) {
3837                 u8 buf[128];
3838                 set_bit(CONF_REQ_SENT, &chan->conf_state);
3839                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3840                                l2cap_build_conf_req(chan, buf), buf);
3841                 chan->num_conf_req++;
3842         }
3843
3844         return chan;
3845 }
3846
3847 static int l2cap_connect_req(struct l2cap_conn *conn,
3848                              struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3849 {
3850         struct hci_dev *hdev = conn->hcon->hdev;
3851         struct hci_conn *hcon = conn->hcon;
3852
3853         if (cmd_len < sizeof(struct l2cap_conn_req))
3854                 return -EPROTO;
3855
3856         hci_dev_lock(hdev);
3857         if (test_bit(HCI_MGMT, &hdev->dev_flags) &&
3858             !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3859                 mgmt_device_connected(hdev, &hcon->dst, hcon->type,
3860                                       hcon->dst_type, 0, NULL, 0,
3861                                       hcon->dev_class);
3862         hci_dev_unlock(hdev);
3863
3864         l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3865         return 0;
3866 }
3867
3868 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3869                                     struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3870                                     u8 *data)
3871 {
3872         struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3873         u16 scid, dcid, result, status;
3874         struct l2cap_chan *chan;
3875         u8 req[128];
3876         int err;
3877
3878         if (cmd_len < sizeof(*rsp))
3879                 return -EPROTO;
3880
3881         scid   = __le16_to_cpu(rsp->scid);
3882         dcid   = __le16_to_cpu(rsp->dcid);
3883         result = __le16_to_cpu(rsp->result);
3884         status = __le16_to_cpu(rsp->status);
3885
3886         BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3887                dcid, scid, result, status);
3888
3889         mutex_lock(&conn->chan_lock);
3890
3891         if (scid) {
3892                 chan = __l2cap_get_chan_by_scid(conn, scid);
3893                 if (!chan) {
3894                         err = -EFAULT;
3895                         goto unlock;
3896                 }
3897         } else {
3898                 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3899                 if (!chan) {
3900                         err = -EFAULT;
3901                         goto unlock;
3902                 }
3903         }
3904
3905         err = 0;
3906
3907         l2cap_chan_lock(chan);
3908
3909         switch (result) {
3910         case L2CAP_CR_SUCCESS:
3911                 l2cap_state_change(chan, BT_CONFIG);
3912                 chan->ident = 0;
3913                 chan->dcid = dcid;
3914                 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3915
3916                 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3917                         break;
3918
3919                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3920                                l2cap_build_conf_req(chan, req), req);
3921                 chan->num_conf_req++;
3922                 break;
3923
3924         case L2CAP_CR_PEND:
3925                 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3926                 break;
3927
3928         default:
3929                 l2cap_chan_del(chan, ECONNREFUSED);
3930                 break;
3931         }
3932
3933         l2cap_chan_unlock(chan);
3934
3935 unlock:
3936         mutex_unlock(&conn->chan_lock);
3937
3938         return err;
3939 }
3940
3941 static inline void set_default_fcs(struct l2cap_chan *chan)
3942 {
3943         /* FCS is enabled only in ERTM or streaming mode, if one or both
3944          * sides request it.
3945          */
3946         if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3947                 chan->fcs = L2CAP_FCS_NONE;
3948         else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
3949                 chan->fcs = L2CAP_FCS_CRC16;
3950 }
3951
3952 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
3953                                     u8 ident, u16 flags)
3954 {
3955         struct l2cap_conn *conn = chan->conn;
3956
3957         BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
3958                flags);
3959
3960         clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3961         set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3962
3963         l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
3964                        l2cap_build_conf_rsp(chan, data,
3965                                             L2CAP_CONF_SUCCESS, flags), data);
3966 }
3967
3968 static inline int l2cap_config_req(struct l2cap_conn *conn,
3969                                    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3970                                    u8 *data)
3971 {
3972         struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
3973         u16 dcid, flags;
3974         u8 rsp[64];
3975         struct l2cap_chan *chan;
3976         int len, err = 0;
3977
3978         if (cmd_len < sizeof(*req))
3979                 return -EPROTO;
3980
3981         dcid  = __le16_to_cpu(req->dcid);
3982         flags = __le16_to_cpu(req->flags);
3983
3984         BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
3985
3986         chan = l2cap_get_chan_by_scid(conn, dcid);
3987         if (!chan)
3988                 return -ENOENT;
3989
3990         if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
3991                 struct l2cap_cmd_rej_cid rej;
3992
3993                 rej.reason = __constant_cpu_to_le16(L2CAP_REJ_INVALID_CID);
3994                 rej.scid = cpu_to_le16(chan->scid);
3995                 rej.dcid = cpu_to_le16(chan->dcid);
3996
3997                 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
3998                                sizeof(rej), &rej);
3999                 goto unlock;
4000         }
4001
4002         /* Reject if config buffer is too small. */
4003         len = cmd_len - sizeof(*req);
4004         if (chan->conf_len + len > sizeof(chan->conf_req)) {
4005                 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4006                                l2cap_build_conf_rsp(chan, rsp,
4007                                L2CAP_CONF_REJECT, flags), rsp);
4008                 goto unlock;
4009         }
4010
4011         /* Store config. */
4012         memcpy(chan->conf_req + chan->conf_len, req->data, len);
4013         chan->conf_len += len;
4014
4015         if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4016                 /* Incomplete config. Send empty response. */
4017                 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4018                                l2cap_build_conf_rsp(chan, rsp,
4019                                L2CAP_CONF_SUCCESS, flags), rsp);
4020                 goto unlock;
4021         }
4022
4023         /* Complete config. */
4024         len = l2cap_parse_conf_req(chan, rsp);
4025         if (len < 0) {
4026                 l2cap_send_disconn_req(chan, ECONNRESET);
4027                 goto unlock;
4028         }
4029
4030         chan->ident = cmd->ident;
4031         l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4032         chan->num_conf_rsp++;
4033
4034         /* Reset config buffer. */
4035         chan->conf_len = 0;
4036
4037         if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4038                 goto unlock;
4039
4040         if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4041                 set_default_fcs(chan);
4042
4043                 if (chan->mode == L2CAP_MODE_ERTM ||
4044                     chan->mode == L2CAP_MODE_STREAMING)
4045                         err = l2cap_ertm_init(chan);
4046
4047                 if (err < 0)
4048                         l2cap_send_disconn_req(chan, -err);
4049                 else
4050                         l2cap_chan_ready(chan);
4051
4052                 goto unlock;
4053         }
4054
4055         if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4056                 u8 buf[64];
4057                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4058                                l2cap_build_conf_req(chan, buf), buf);
4059                 chan->num_conf_req++;
4060         }
4061
4062         /* Got Conf Rsp PENDING from remote side and asume we sent
4063            Conf Rsp PENDING in the code above */
4064         if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4065             test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4066
4067                 /* check compatibility */
4068
4069                 /* Send rsp for BR/EDR channel */
4070                 if (!chan->hs_hcon)
4071                         l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4072                 else
4073                         chan->ident = cmd->ident;
4074         }
4075
4076 unlock:
4077         l2cap_chan_unlock(chan);
4078         return err;
4079 }
4080
4081 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4082                                    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4083                                    u8 *data)
4084 {
4085         struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4086         u16 scid, flags, result;
4087         struct l2cap_chan *chan;
4088         int len = cmd_len - sizeof(*rsp);
4089         int err = 0;
4090
4091         if (cmd_len < sizeof(*rsp))
4092                 return -EPROTO;
4093
4094         scid   = __le16_to_cpu(rsp->scid);
4095         flags  = __le16_to_cpu(rsp->flags);
4096         result = __le16_to_cpu(rsp->result);
4097
4098         BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4099                result, len);
4100
4101         chan = l2cap_get_chan_by_scid(conn, scid);
4102         if (!chan)
4103                 return 0;
4104
4105         switch (result) {
4106         case L2CAP_CONF_SUCCESS:
4107                 l2cap_conf_rfc_get(chan, rsp->data, len);
4108                 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4109                 break;
4110
4111         case L2CAP_CONF_PENDING:
4112                 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4113
4114                 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4115                         char buf[64];
4116
4117                         len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4118                                                    buf, &result);
4119                         if (len < 0) {
4120                                 l2cap_send_disconn_req(chan, ECONNRESET);
4121                                 goto done;
4122                         }
4123
4124                         if (!chan->hs_hcon) {
4125                                 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4126                                                         0);
4127                         } else {
4128                                 if (l2cap_check_efs(chan)) {
4129                                         amp_create_logical_link(chan);
4130                                         chan->ident = cmd->ident;
4131                                 }
4132                         }
4133                 }
4134                 goto done;
4135
4136         case L2CAP_CONF_UNACCEPT:
4137                 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4138                         char req[64];
4139
4140                         if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4141                                 l2cap_send_disconn_req(chan, ECONNRESET);
4142                                 goto done;
4143                         }
4144
4145                         /* throw out any old stored conf requests */
4146                         result = L2CAP_CONF_SUCCESS;
4147                         len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4148                                                    req, &result);
4149                         if (len < 0) {
4150                                 l2cap_send_disconn_req(chan, ECONNRESET);
4151                                 goto done;
4152                         }
4153
4154                         l2cap_send_cmd(conn, l2cap_get_ident(conn),
4155                                        L2CAP_CONF_REQ, len, req);
4156                         chan->num_conf_req++;
4157                         if (result != L2CAP_CONF_SUCCESS)
4158                                 goto done;
4159                         break;
4160                 }
4161
4162         default:
4163                 l2cap_chan_set_err(chan, ECONNRESET);
4164
4165                 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4166                 l2cap_send_disconn_req(chan, ECONNRESET);
4167                 goto done;
4168         }
4169
4170         if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4171                 goto done;
4172
4173         set_bit(CONF_INPUT_DONE, &chan->conf_state);
4174
4175         if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4176                 set_default_fcs(chan);
4177
4178                 if (chan->mode == L2CAP_MODE_ERTM ||
4179                     chan->mode == L2CAP_MODE_STREAMING)
4180                         err = l2cap_ertm_init(chan);
4181
4182                 if (err < 0)
4183                         l2cap_send_disconn_req(chan, -err);
4184                 else
4185                         l2cap_chan_ready(chan);
4186         }
4187
4188 done:
4189         l2cap_chan_unlock(chan);
4190         return err;
4191 }
4192
4193 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4194                                        struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4195                                        u8 *data)
4196 {
4197         struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4198         struct l2cap_disconn_rsp rsp;
4199         u16 dcid, scid;
4200         struct l2cap_chan *chan;
4201         struct sock *sk;
4202
4203         if (cmd_len != sizeof(*req))
4204                 return -EPROTO;
4205
4206         scid = __le16_to_cpu(req->scid);
4207         dcid = __le16_to_cpu(req->dcid);
4208
4209         BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4210
4211         mutex_lock(&conn->chan_lock);
4212
4213         chan = __l2cap_get_chan_by_scid(conn, dcid);
4214         if (!chan) {
4215                 mutex_unlock(&conn->chan_lock);
4216                 return 0;
4217         }
4218
4219         l2cap_chan_lock(chan);
4220
4221         sk = chan->sk;
4222
4223         rsp.dcid = cpu_to_le16(chan->scid);
4224         rsp.scid = cpu_to_le16(chan->dcid);
4225         l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4226
4227         lock_sock(sk);
4228         sk->sk_shutdown = SHUTDOWN_MASK;
4229         release_sock(sk);
4230
4231         l2cap_chan_hold(chan);
4232         l2cap_chan_del(chan, ECONNRESET);
4233
4234         l2cap_chan_unlock(chan);
4235
4236         chan->ops->close(chan);
4237         l2cap_chan_put(chan);
4238
4239         mutex_unlock(&conn->chan_lock);
4240
4241         return 0;
4242 }
4243
4244 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4245                                        struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4246                                        u8 *data)
4247 {
4248         struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4249         u16 dcid, scid;
4250         struct l2cap_chan *chan;
4251
4252         if (cmd_len != sizeof(*rsp))
4253                 return -EPROTO;
4254
4255         scid = __le16_to_cpu(rsp->scid);
4256         dcid = __le16_to_cpu(rsp->dcid);
4257
4258         BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4259
4260         mutex_lock(&conn->chan_lock);
4261
4262         chan = __l2cap_get_chan_by_scid(conn, scid);
4263         if (!chan) {
4264                 mutex_unlock(&conn->chan_lock);
4265                 return 0;
4266         }
4267
4268         l2cap_chan_lock(chan);
4269
4270         l2cap_chan_hold(chan);
4271         l2cap_chan_del(chan, 0);
4272
4273         l2cap_chan_unlock(chan);
4274
4275         chan->ops->close(chan);
4276         l2cap_chan_put(chan);
4277
4278         mutex_unlock(&conn->chan_lock);
4279
4280         return 0;
4281 }
4282
4283 static inline int l2cap_information_req(struct l2cap_conn *conn,
4284                                         struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4285                                         u8 *data)
4286 {
4287         struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4288         u16 type;
4289
4290         if (cmd_len != sizeof(*req))
4291                 return -EPROTO;
4292
4293         type = __le16_to_cpu(req->type);
4294
4295         BT_DBG("type 0x%4.4x", type);
4296
4297         if (type == L2CAP_IT_FEAT_MASK) {
4298                 u8 buf[8];
4299                 u32 feat_mask = l2cap_feat_mask;
4300                 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4301                 rsp->type   = __constant_cpu_to_le16(L2CAP_IT_FEAT_MASK);
4302                 rsp->result = __constant_cpu_to_le16(L2CAP_IR_SUCCESS);
4303                 if (!disable_ertm)
4304                         feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4305                                 | L2CAP_FEAT_FCS;
4306                 if (enable_hs)
4307                         feat_mask |= L2CAP_FEAT_EXT_FLOW
4308                                 | L2CAP_FEAT_EXT_WINDOW;
4309
4310                 put_unaligned_le32(feat_mask, rsp->data);
4311                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4312                                buf);
4313         } else if (type == L2CAP_IT_FIXED_CHAN) {
4314                 u8 buf[12];
4315                 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4316
4317                 if (enable_hs)
4318                         l2cap_fixed_chan[0] |= L2CAP_FC_A2MP;
4319                 else
4320                         l2cap_fixed_chan[0] &= ~L2CAP_FC_A2MP;
4321
4322                 rsp->type   = __constant_cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4323                 rsp->result = __constant_cpu_to_le16(L2CAP_IR_SUCCESS);
4324                 memcpy(rsp->data, l2cap_fixed_chan, sizeof(l2cap_fixed_chan));
4325                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4326                                buf);
4327         } else {
4328                 struct l2cap_info_rsp rsp;
4329                 rsp.type   = cpu_to_le16(type);
4330                 rsp.result = __constant_cpu_to_le16(L2CAP_IR_NOTSUPP);
4331                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4332                                &rsp);
4333         }
4334
4335         return 0;
4336 }
4337
4338 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4339                                         struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4340                                         u8 *data)
4341 {
4342         struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4343         u16 type, result;
4344
4345         if (cmd_len < sizeof(*rsp))
4346                 return -EPROTO;
4347
4348         type   = __le16_to_cpu(rsp->type);
4349         result = __le16_to_cpu(rsp->result);
4350
4351         BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4352
4353         /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4354         if (cmd->ident != conn->info_ident ||
4355             conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4356                 return 0;
4357
4358         cancel_delayed_work(&conn->info_timer);
4359
4360         if (result != L2CAP_IR_SUCCESS) {
4361                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4362                 conn->info_ident = 0;
4363
4364                 l2cap_conn_start(conn);
4365
4366                 return 0;
4367         }
4368
4369         switch (type) {
4370         case L2CAP_IT_FEAT_MASK:
4371                 conn->feat_mask = get_unaligned_le32(rsp->data);
4372
4373                 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4374                         struct l2cap_info_req req;
4375                         req.type = __constant_cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4376
4377                         conn->info_ident = l2cap_get_ident(conn);
4378
4379                         l2cap_send_cmd(conn, conn->info_ident,
4380                                        L2CAP_INFO_REQ, sizeof(req), &req);
4381                 } else {
4382                         conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4383                         conn->info_ident = 0;
4384
4385                         l2cap_conn_start(conn);
4386                 }
4387                 break;
4388
4389         case L2CAP_IT_FIXED_CHAN:
4390                 conn->fixed_chan_mask = rsp->data[0];
4391                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4392                 conn->info_ident = 0;
4393
4394                 l2cap_conn_start(conn);
4395                 break;
4396         }
4397
4398         return 0;
4399 }
4400
4401 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4402                                     struct l2cap_cmd_hdr *cmd,
4403                                     u16 cmd_len, void *data)
4404 {
4405         struct l2cap_create_chan_req *req = data;
4406         struct l2cap_create_chan_rsp rsp;
4407         struct l2cap_chan *chan;
4408         struct hci_dev *hdev;
4409         u16 psm, scid;
4410
4411         if (cmd_len != sizeof(*req))
4412                 return -EPROTO;
4413
4414         if (!enable_hs)
4415                 return -EINVAL;
4416
4417         psm = le16_to_cpu(req->psm);
4418         scid = le16_to_cpu(req->scid);
4419
4420         BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4421
4422         /* For controller id 0 make BR/EDR connection */
4423         if (req->amp_id == HCI_BREDR_ID) {
4424                 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4425                               req->amp_id);
4426                 return 0;
4427         }
4428
4429         /* Validate AMP controller id */
4430         hdev = hci_dev_get(req->amp_id);
4431         if (!hdev)
4432                 goto error;
4433
4434         if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4435                 hci_dev_put(hdev);
4436                 goto error;
4437         }
4438
4439         chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4440                              req->amp_id);
4441         if (chan) {
4442                 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4443                 struct hci_conn *hs_hcon;
4444
4445                 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK, conn->dst);
4446                 if (!hs_hcon) {
4447                         hci_dev_put(hdev);
4448                         return -EFAULT;
4449                 }
4450
4451                 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4452
4453                 mgr->bredr_chan = chan;
4454                 chan->hs_hcon = hs_hcon;
4455                 chan->fcs = L2CAP_FCS_NONE;
4456                 conn->mtu = hdev->block_mtu;
4457         }
4458
4459         hci_dev_put(hdev);
4460
4461         return 0;
4462
4463 error:
4464         rsp.dcid = 0;
4465         rsp.scid = cpu_to_le16(scid);
4466         rsp.result = __constant_cpu_to_le16(L2CAP_CR_BAD_AMP);
4467         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4468
4469         l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4470                        sizeof(rsp), &rsp);
4471
4472         return -EFAULT;
4473 }
4474
4475 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4476 {
4477         struct l2cap_move_chan_req req;
4478         u8 ident;
4479
4480         BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4481
4482         ident = l2cap_get_ident(chan->conn);
4483         chan->ident = ident;
4484
4485         req.icid = cpu_to_le16(chan->scid);
4486         req.dest_amp_id = dest_amp_id;
4487
4488         l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4489                        &req);
4490
4491         __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4492 }
4493
4494 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4495 {
4496         struct l2cap_move_chan_rsp rsp;
4497
4498         BT_DBG("chan %p, result 0x%4.4x", chan, result);
4499
4500         rsp.icid = cpu_to_le16(chan->dcid);
4501         rsp.result = cpu_to_le16(result);
4502
4503         l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4504                        sizeof(rsp), &rsp);
4505 }
4506
4507 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4508 {
4509         struct l2cap_move_chan_cfm cfm;
4510
4511         BT_DBG("chan %p, result 0x%4.4x", chan, result);
4512
4513         chan->ident = l2cap_get_ident(chan->conn);
4514
4515         cfm.icid = cpu_to_le16(chan->scid);
4516         cfm.result = cpu_to_le16(result);
4517
4518         l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4519                        sizeof(cfm), &cfm);
4520
4521         __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4522 }
4523
4524 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4525 {
4526         struct l2cap_move_chan_cfm cfm;
4527
4528         BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4529
4530         cfm.icid = cpu_to_le16(icid);
4531         cfm.result = __constant_cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4532
4533         l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4534                        sizeof(cfm), &cfm);
4535 }
4536
4537 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4538                                          u16 icid)
4539 {
4540         struct l2cap_move_chan_cfm_rsp rsp;
4541
4542         BT_DBG("icid 0x%4.4x", icid);
4543
4544         rsp.icid = cpu_to_le16(icid);
4545         l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4546 }
4547
4548 static void __release_logical_link(struct l2cap_chan *chan)
4549 {
4550         chan->hs_hchan = NULL;
4551         chan->hs_hcon = NULL;
4552
4553         /* Placeholder - release the logical link */
4554 }
4555
4556 static void l2cap_logical_fail(struct l2cap_chan *chan)
4557 {
4558         /* Logical link setup failed */
4559         if (chan->state != BT_CONNECTED) {
4560                 /* Create channel failure, disconnect */
4561                 l2cap_send_disconn_req(chan, ECONNRESET);
4562                 return;
4563         }
4564
4565         switch (chan->move_role) {
4566         case L2CAP_MOVE_ROLE_RESPONDER:
4567                 l2cap_move_done(chan);
4568                 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4569                 break;
4570         case L2CAP_MOVE_ROLE_INITIATOR:
4571                 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4572                     chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4573                         /* Remote has only sent pending or
4574                          * success responses, clean up
4575                          */
4576                         l2cap_move_done(chan);
4577                 }
4578
4579                 /* Other amp move states imply that the move
4580                  * has already aborted
4581                  */
4582                 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4583                 break;
4584         }
4585 }
4586
4587 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4588                                         struct hci_chan *hchan)
4589 {
4590         struct l2cap_conf_rsp rsp;
4591
4592         chan->hs_hchan = hchan;
4593         chan->hs_hcon->l2cap_data = chan->conn;
4594
4595         l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4596
4597         if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4598                 int err;
4599
4600                 set_default_fcs(chan);
4601
4602                 err = l2cap_ertm_init(chan);
4603                 if (err < 0)
4604                         l2cap_send_disconn_req(chan, -err);
4605                 else
4606                         l2cap_chan_ready(chan);
4607         }
4608 }
4609
4610 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4611                                       struct hci_chan *hchan)
4612 {
4613         chan->hs_hcon = hchan->conn;
4614         chan->hs_hcon->l2cap_data = chan->conn;
4615
4616         BT_DBG("move_state %d", chan->move_state);
4617
4618         switch (chan->move_state) {
4619         case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4620                 /* Move confirm will be sent after a success
4621                  * response is received
4622                  */
4623                 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4624                 break;
4625         case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4626                 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4627                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4628                 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4629                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4630                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4631                 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4632                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4633                         l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4634                 }
4635                 break;
4636         default:
4637                 /* Move was not in expected state, free the channel */
4638                 __release_logical_link(chan);
4639
4640                 chan->move_state = L2CAP_MOVE_STABLE;
4641         }
4642 }
4643
4644 /* Call with chan locked */
4645 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4646                        u8 status)
4647 {
4648         BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4649
4650         if (status) {
4651                 l2cap_logical_fail(chan);
4652                 __release_logical_link(chan);
4653                 return;
4654         }
4655
4656         if (chan->state != BT_CONNECTED) {
4657                 /* Ignore logical link if channel is on BR/EDR */
4658                 if (chan->local_amp_id)
4659                         l2cap_logical_finish_create(chan, hchan);
4660         } else {
4661                 l2cap_logical_finish_move(chan, hchan);
4662         }
4663 }
4664
4665 void l2cap_move_start(struct l2cap_chan *chan)
4666 {
4667         BT_DBG("chan %p", chan);
4668
4669         if (chan->local_amp_id == HCI_BREDR_ID) {
4670                 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4671                         return;
4672                 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4673                 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4674                 /* Placeholder - start physical link setup */
4675         } else {
4676                 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4677                 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4678                 chan->move_id = 0;
4679                 l2cap_move_setup(chan);
4680                 l2cap_send_move_chan_req(chan, 0);
4681         }
4682 }
4683
4684 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4685                             u8 local_amp_id, u8 remote_amp_id)
4686 {
4687         BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4688                local_amp_id, remote_amp_id);
4689
4690         chan->fcs = L2CAP_FCS_NONE;
4691
4692         /* Outgoing channel on AMP */
4693         if (chan->state == BT_CONNECT) {
4694                 if (result == L2CAP_CR_SUCCESS) {
4695                         chan->local_amp_id = local_amp_id;
4696                         l2cap_send_create_chan_req(chan, remote_amp_id);
4697                 } else {
4698                         /* Revert to BR/EDR connect */
4699                         l2cap_send_conn_req(chan);
4700                 }
4701
4702                 return;
4703         }
4704
4705         /* Incoming channel on AMP */
4706         if (__l2cap_no_conn_pending(chan)) {
4707                 struct l2cap_conn_rsp rsp;
4708                 char buf[128];
4709                 rsp.scid = cpu_to_le16(chan->dcid);
4710                 rsp.dcid = cpu_to_le16(chan->scid);
4711
4712                 if (result == L2CAP_CR_SUCCESS) {
4713                         /* Send successful response */
4714                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_SUCCESS);
4715                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4716                 } else {
4717                         /* Send negative response */
4718                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_NO_MEM);
4719                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4720                 }
4721
4722                 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4723                                sizeof(rsp), &rsp);
4724
4725                 if (result == L2CAP_CR_SUCCESS) {
4726                         __l2cap_state_change(chan, BT_CONFIG);
4727                         set_bit(CONF_REQ_SENT, &chan->conf_state);
4728                         l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4729                                        L2CAP_CONF_REQ,
4730                                        l2cap_build_conf_req(chan, buf), buf);
4731                         chan->num_conf_req++;
4732                 }
4733         }
4734 }
4735
4736 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4737                                    u8 remote_amp_id)
4738 {
4739         l2cap_move_setup(chan);
4740         chan->move_id = local_amp_id;
4741         chan->move_state = L2CAP_MOVE_WAIT_RSP;
4742
4743         l2cap_send_move_chan_req(chan, remote_amp_id);
4744 }
4745
4746 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4747 {
4748         struct hci_chan *hchan = NULL;
4749
4750         /* Placeholder - get hci_chan for logical link */
4751
4752         if (hchan) {
4753                 if (hchan->state == BT_CONNECTED) {
4754                         /* Logical link is ready to go */
4755                         chan->hs_hcon = hchan->conn;
4756                         chan->hs_hcon->l2cap_data = chan->conn;
4757                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4758                         l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4759
4760                         l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4761                 } else {
4762                         /* Wait for logical link to be ready */
4763                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4764                 }
4765         } else {
4766                 /* Logical link not available */
4767                 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4768         }
4769 }
4770
4771 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4772 {
4773         if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4774                 u8 rsp_result;
4775                 if (result == -EINVAL)
4776                         rsp_result = L2CAP_MR_BAD_ID;
4777                 else
4778                         rsp_result = L2CAP_MR_NOT_ALLOWED;
4779
4780                 l2cap_send_move_chan_rsp(chan, rsp_result);
4781         }
4782
4783         chan->move_role = L2CAP_MOVE_ROLE_NONE;
4784         chan->move_state = L2CAP_MOVE_STABLE;
4785
4786         /* Restart data transmission */
4787         l2cap_ertm_send(chan);
4788 }
4789
4790 /* Invoke with locked chan */
4791 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4792 {
4793         u8 local_amp_id = chan->local_amp_id;
4794         u8 remote_amp_id = chan->remote_amp_id;
4795
4796         BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4797                chan, result, local_amp_id, remote_amp_id);
4798
4799         if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4800                 l2cap_chan_unlock(chan);
4801                 return;
4802         }
4803
4804         if (chan->state != BT_CONNECTED) {
4805                 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4806         } else if (result != L2CAP_MR_SUCCESS) {
4807                 l2cap_do_move_cancel(chan, result);
4808         } else {
4809                 switch (chan->move_role) {
4810                 case L2CAP_MOVE_ROLE_INITIATOR:
4811                         l2cap_do_move_initiate(chan, local_amp_id,
4812                                                remote_amp_id);
4813                         break;
4814                 case L2CAP_MOVE_ROLE_RESPONDER:
4815                         l2cap_do_move_respond(chan, result);
4816                         break;
4817                 default:
4818                         l2cap_do_move_cancel(chan, result);
4819                         break;
4820                 }
4821         }
4822 }
4823
4824 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4825                                          struct l2cap_cmd_hdr *cmd,
4826                                          u16 cmd_len, void *data)
4827 {
4828         struct l2cap_move_chan_req *req = data;
4829         struct l2cap_move_chan_rsp rsp;
4830         struct l2cap_chan *chan;
4831         u16 icid = 0;
4832         u16 result = L2CAP_MR_NOT_ALLOWED;
4833
4834         if (cmd_len != sizeof(*req))
4835                 return -EPROTO;
4836
4837         icid = le16_to_cpu(req->icid);
4838
4839         BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4840
4841         if (!enable_hs)
4842                 return -EINVAL;
4843
4844         chan = l2cap_get_chan_by_dcid(conn, icid);
4845         if (!chan) {
4846                 rsp.icid = cpu_to_le16(icid);
4847                 rsp.result = __constant_cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4848                 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4849                                sizeof(rsp), &rsp);
4850                 return 0;
4851         }
4852
4853         chan->ident = cmd->ident;
4854
4855         if (chan->scid < L2CAP_CID_DYN_START ||
4856             chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4857             (chan->mode != L2CAP_MODE_ERTM &&
4858              chan->mode != L2CAP_MODE_STREAMING)) {
4859                 result = L2CAP_MR_NOT_ALLOWED;
4860                 goto send_move_response;
4861         }
4862
4863         if (chan->local_amp_id == req->dest_amp_id) {
4864                 result = L2CAP_MR_SAME_ID;
4865                 goto send_move_response;
4866         }
4867
4868         if (req->dest_amp_id) {
4869                 struct hci_dev *hdev;
4870                 hdev = hci_dev_get(req->dest_amp_id);
4871                 if (!hdev || hdev->dev_type != HCI_AMP ||
4872                     !test_bit(HCI_UP, &hdev->flags)) {
4873                         if (hdev)
4874                                 hci_dev_put(hdev);
4875
4876                         result = L2CAP_MR_BAD_ID;
4877                         goto send_move_response;
4878                 }
4879                 hci_dev_put(hdev);
4880         }
4881
4882         /* Detect a move collision.  Only send a collision response
4883          * if this side has "lost", otherwise proceed with the move.
4884          * The winner has the larger bd_addr.
4885          */
4886         if ((__chan_is_moving(chan) ||
4887              chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4888             bacmp(conn->src, conn->dst) > 0) {
4889                 result = L2CAP_MR_COLLISION;
4890                 goto send_move_response;
4891         }
4892
4893         chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4894         l2cap_move_setup(chan);
4895         chan->move_id = req->dest_amp_id;
4896         icid = chan->dcid;
4897
4898         if (!req->dest_amp_id) {
4899                 /* Moving to BR/EDR */
4900                 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4901                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4902                         result = L2CAP_MR_PEND;
4903                 } else {
4904                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4905                         result = L2CAP_MR_SUCCESS;
4906                 }
4907         } else {
4908                 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4909                 /* Placeholder - uncomment when amp functions are available */
4910                 /*amp_accept_physical(chan, req->dest_amp_id);*/
4911                 result = L2CAP_MR_PEND;
4912         }
4913
4914 send_move_response:
4915         l2cap_send_move_chan_rsp(chan, result);
4916
4917         l2cap_chan_unlock(chan);
4918
4919         return 0;
4920 }
4921
4922 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4923 {
4924         struct l2cap_chan *chan;
4925         struct hci_chan *hchan = NULL;
4926
4927         chan = l2cap_get_chan_by_scid(conn, icid);
4928         if (!chan) {
4929                 l2cap_send_move_chan_cfm_icid(conn, icid);
4930                 return;
4931         }
4932
4933         __clear_chan_timer(chan);
4934         if (result == L2CAP_MR_PEND)
4935                 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4936
4937         switch (chan->move_state) {
4938         case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4939                 /* Move confirm will be sent when logical link
4940                  * is complete.
4941                  */
4942                 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4943                 break;
4944         case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4945                 if (result == L2CAP_MR_PEND) {
4946                         break;
4947                 } else if (test_bit(CONN_LOCAL_BUSY,
4948                                     &chan->conn_state)) {
4949                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4950                 } else {
4951                         /* Logical link is up or moving to BR/EDR,
4952                          * proceed with move
4953                          */
4954                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4955                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4956                 }
4957                 break;
4958         case L2CAP_MOVE_WAIT_RSP:
4959                 /* Moving to AMP */
4960                 if (result == L2CAP_MR_SUCCESS) {
4961                         /* Remote is ready, send confirm immediately
4962                          * after logical link is ready
4963                          */
4964                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4965                 } else {
4966                         /* Both logical link and move success
4967                          * are required to confirm
4968                          */
4969                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
4970                 }
4971
4972                 /* Placeholder - get hci_chan for logical link */
4973                 if (!hchan) {
4974                         /* Logical link not available */
4975                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4976                         break;
4977                 }
4978
4979                 /* If the logical link is not yet connected, do not
4980                  * send confirmation.
4981                  */
4982                 if (hchan->state != BT_CONNECTED)
4983                         break;
4984
4985                 /* Logical link is already ready to go */
4986
4987                 chan->hs_hcon = hchan->conn;
4988                 chan->hs_hcon->l2cap_data = chan->conn;
4989
4990                 if (result == L2CAP_MR_SUCCESS) {
4991                         /* Can confirm now */
4992                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4993                 } else {
4994                         /* Now only need move success
4995                          * to confirm
4996                          */
4997                         chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4998                 }
4999
5000                 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5001                 break;
5002         default:
5003                 /* Any other amp move state means the move failed. */
5004                 chan->move_id = chan->local_amp_id;
5005                 l2cap_move_done(chan);
5006                 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5007         }
5008
5009         l2cap_chan_unlock(chan);
5010 }
5011
5012 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5013                             u16 result)
5014 {
5015         struct l2cap_chan *chan;
5016
5017         chan = l2cap_get_chan_by_ident(conn, ident);
5018         if (!chan) {
5019                 /* Could not locate channel, icid is best guess */
5020                 l2cap_send_move_chan_cfm_icid(conn, icid);
5021                 return;
5022         }
5023
5024         __clear_chan_timer(chan);
5025
5026         if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5027                 if (result == L2CAP_MR_COLLISION) {
5028                         chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5029                 } else {
5030                         /* Cleanup - cancel move */
5031                         chan->move_id = chan->local_amp_id;
5032                         l2cap_move_done(chan);
5033                 }
5034         }
5035
5036         l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5037
5038         l2cap_chan_unlock(chan);
5039 }
5040
5041 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5042                                   struct l2cap_cmd_hdr *cmd,
5043                                   u16 cmd_len, void *data)
5044 {
5045         struct l2cap_move_chan_rsp *rsp = data;
5046         u16 icid, result;
5047
5048         if (cmd_len != sizeof(*rsp))
5049                 return -EPROTO;
5050
5051         icid = le16_to_cpu(rsp->icid);
5052         result = le16_to_cpu(rsp->result);
5053
5054         BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5055
5056         if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5057                 l2cap_move_continue(conn, icid, result);
5058         else
5059                 l2cap_move_fail(conn, cmd->ident, icid, result);
5060
5061         return 0;
5062 }
5063
5064 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5065                                       struct l2cap_cmd_hdr *cmd,
5066                                       u16 cmd_len, void *data)
5067 {
5068         struct l2cap_move_chan_cfm *cfm = data;
5069         struct l2cap_chan *chan;
5070         u16 icid, result;
5071
5072         if (cmd_len != sizeof(*cfm))
5073                 return -EPROTO;
5074
5075         icid = le16_to_cpu(cfm->icid);
5076         result = le16_to_cpu(cfm->result);
5077
5078         BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5079
5080         chan = l2cap_get_chan_by_dcid(conn, icid);
5081         if (!chan) {
5082                 /* Spec requires a response even if the icid was not found */
5083                 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5084                 return 0;
5085         }
5086
5087         if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5088                 if (result == L2CAP_MC_CONFIRMED) {
5089                         chan->local_amp_id = chan->move_id;
5090                         if (!chan->local_amp_id)
5091                                 __release_logical_link(chan);
5092                 } else {
5093                         chan->move_id = chan->local_amp_id;
5094                 }
5095
5096                 l2cap_move_done(chan);
5097         }
5098
5099         l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5100
5101         l2cap_chan_unlock(chan);
5102
5103         return 0;
5104 }
5105
5106 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5107                                                  struct l2cap_cmd_hdr *cmd,
5108                                                  u16 cmd_len, void *data)
5109 {
5110         struct l2cap_move_chan_cfm_rsp *rsp = data;
5111         struct l2cap_chan *chan;
5112         u16 icid;
5113
5114         if (cmd_len != sizeof(*rsp))
5115                 return -EPROTO;
5116
5117         icid = le16_to_cpu(rsp->icid);
5118
5119         BT_DBG("icid 0x%4.4x", icid);
5120
5121         chan = l2cap_get_chan_by_scid(conn, icid);
5122         if (!chan)
5123                 return 0;
5124
5125         __clear_chan_timer(chan);
5126
5127         if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5128                 chan->local_amp_id = chan->move_id;
5129
5130                 if (!chan->local_amp_id && chan->hs_hchan)
5131                         __release_logical_link(chan);
5132
5133                 l2cap_move_done(chan);
5134         }
5135
5136         l2cap_chan_unlock(chan);
5137
5138         return 0;
5139 }
5140
5141 static inline int l2cap_check_conn_param(u16 min, u16 max, u16 latency,
5142                                          u16 to_multiplier)
5143 {
5144         u16 max_latency;
5145
5146         if (min > max || min < 6 || max > 3200)
5147                 return -EINVAL;
5148
5149         if (to_multiplier < 10 || to_multiplier > 3200)
5150                 return -EINVAL;
5151
5152         if (max >= to_multiplier * 8)
5153                 return -EINVAL;
5154
5155         max_latency = (to_multiplier * 8 / max) - 1;
5156         if (latency > 499 || latency > max_latency)
5157                 return -EINVAL;
5158
5159         return 0;
5160 }
5161
5162 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5163                                               struct l2cap_cmd_hdr *cmd,
5164                                               u8 *data)
5165 {
5166         struct hci_conn *hcon = conn->hcon;
5167         struct l2cap_conn_param_update_req *req;
5168         struct l2cap_conn_param_update_rsp rsp;
5169         u16 min, max, latency, to_multiplier, cmd_len;
5170         int err;
5171
5172         if (!(hcon->link_mode & HCI_LM_MASTER))
5173                 return -EINVAL;
5174
5175         cmd_len = __le16_to_cpu(cmd->len);
5176         if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5177                 return -EPROTO;
5178
5179         req = (struct l2cap_conn_param_update_req *) data;
5180         min             = __le16_to_cpu(req->min);
5181         max             = __le16_to_cpu(req->max);
5182         latency         = __le16_to_cpu(req->latency);
5183         to_multiplier   = __le16_to_cpu(req->to_multiplier);
5184
5185         BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5186                min, max, latency, to_multiplier);
5187
5188         memset(&rsp, 0, sizeof(rsp));
5189
5190         err = l2cap_check_conn_param(min, max, latency, to_multiplier);
5191         if (err)
5192                 rsp.result = __constant_cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5193         else
5194                 rsp.result = __constant_cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5195
5196         l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5197                        sizeof(rsp), &rsp);
5198
5199         if (!err)
5200                 hci_le_conn_update(hcon, min, max, latency, to_multiplier);
5201
5202         return 0;
5203 }
5204
5205 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5206                                       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5207                                       u8 *data)
5208 {
5209         int err = 0;
5210
5211         switch (cmd->code) {
5212         case L2CAP_COMMAND_REJ:
5213                 l2cap_command_rej(conn, cmd, cmd_len, data);
5214                 break;
5215
5216         case L2CAP_CONN_REQ:
5217                 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5218                 break;
5219
5220         case L2CAP_CONN_RSP:
5221         case L2CAP_CREATE_CHAN_RSP:
5222                 err = l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5223                 break;
5224
5225         case L2CAP_CONF_REQ:
5226                 err = l2cap_config_req(conn, cmd, cmd_len, data);
5227                 break;
5228
5229         case L2CAP_CONF_RSP:
5230                 err = l2cap_config_rsp(conn, cmd, cmd_len, data);
5231                 break;
5232
5233         case L2CAP_DISCONN_REQ:
5234                 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5235                 break;
5236
5237         case L2CAP_DISCONN_RSP:
5238                 err = l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5239                 break;
5240
5241         case L2CAP_ECHO_REQ:
5242                 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5243                 break;
5244
5245         case L2CAP_ECHO_RSP:
5246                 break;
5247
5248         case L2CAP_INFO_REQ:
5249                 err = l2cap_information_req(conn, cmd, cmd_len, data);
5250                 break;
5251
5252         case L2CAP_INFO_RSP:
5253                 err = l2cap_information_rsp(conn, cmd, cmd_len, data);
5254                 break;
5255
5256         case L2CAP_CREATE_CHAN_REQ:
5257                 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5258                 break;
5259
5260         case L2CAP_MOVE_CHAN_REQ:
5261                 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5262                 break;
5263
5264         case L2CAP_MOVE_CHAN_RSP:
5265                 err = l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5266                 break;
5267
5268         case L2CAP_MOVE_CHAN_CFM:
5269                 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5270                 break;
5271
5272         case L2CAP_MOVE_CHAN_CFM_RSP:
5273                 err = l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5274                 break;
5275
5276         default:
5277                 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5278                 err = -EINVAL;
5279                 break;
5280         }
5281
5282         return err;
5283 }
5284
5285 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5286                                    struct l2cap_cmd_hdr *cmd, u8 *data)
5287 {
5288         switch (cmd->code) {
5289         case L2CAP_COMMAND_REJ:
5290                 return 0;
5291
5292         case L2CAP_CONN_PARAM_UPDATE_REQ:
5293                 return l2cap_conn_param_update_req(conn, cmd, data);
5294
5295         case L2CAP_CONN_PARAM_UPDATE_RSP:
5296                 return 0;
5297
5298         default:
5299                 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5300                 return -EINVAL;
5301         }
5302 }
5303
5304 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5305                                         struct sk_buff *skb)
5306 {
5307         u8 *data = skb->data;
5308         int len = skb->len;
5309         struct l2cap_cmd_hdr cmd;
5310         int err;
5311
5312         l2cap_raw_recv(conn, skb);
5313
5314         while (len >= L2CAP_CMD_HDR_SIZE) {
5315                 u16 cmd_len;
5316                 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5317                 data += L2CAP_CMD_HDR_SIZE;
5318                 len  -= L2CAP_CMD_HDR_SIZE;
5319
5320                 cmd_len = le16_to_cpu(cmd.len);
5321
5322                 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5323                        cmd.ident);
5324
5325                 if (cmd_len > len || !cmd.ident) {
5326                         BT_DBG("corrupted command");
5327                         break;
5328                 }
5329
5330                 err = l2cap_le_sig_cmd(conn, &cmd, data);
5331                 if (err) {
5332                         struct l2cap_cmd_rej_unk rej;
5333
5334                         BT_ERR("Wrong link type (%d)", err);
5335
5336                         /* FIXME: Map err to a valid reason */
5337                         rej.reason = __constant_cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5338                         l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5339                                        sizeof(rej), &rej);
5340                 }
5341
5342                 data += cmd_len;
5343                 len  -= cmd_len;
5344         }
5345
5346         kfree_skb(skb);
5347 }
5348
5349 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5350                                      struct sk_buff *skb)
5351 {
5352         u8 *data = skb->data;
5353         int len = skb->len;
5354         struct l2cap_cmd_hdr cmd;
5355         int err;
5356
5357         l2cap_raw_recv(conn, skb);
5358
5359         while (len >= L2CAP_CMD_HDR_SIZE) {
5360                 u16 cmd_len;
5361                 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5362                 data += L2CAP_CMD_HDR_SIZE;
5363                 len  -= L2CAP_CMD_HDR_SIZE;
5364
5365                 cmd_len = le16_to_cpu(cmd.len);
5366
5367                 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5368                        cmd.ident);
5369
5370                 if (cmd_len > len || !cmd.ident) {
5371                         BT_DBG("corrupted command");
5372                         break;
5373                 }
5374
5375                 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5376                 if (err) {
5377                         struct l2cap_cmd_rej_unk rej;
5378
5379                         BT_ERR("Wrong link type (%d)", err);
5380
5381                         /* FIXME: Map err to a valid reason */
5382                         rej.reason = __constant_cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5383                         l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5384                                        sizeof(rej), &rej);
5385                 }
5386
5387                 data += cmd_len;
5388                 len  -= cmd_len;
5389         }
5390
5391         kfree_skb(skb);
5392 }
5393
5394 static int l2cap_check_fcs(struct l2cap_chan *chan,  struct sk_buff *skb)
5395 {
5396         u16 our_fcs, rcv_fcs;
5397         int hdr_size;
5398
5399         if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5400                 hdr_size = L2CAP_EXT_HDR_SIZE;
5401         else
5402                 hdr_size = L2CAP_ENH_HDR_SIZE;
5403
5404         if (chan->fcs == L2CAP_FCS_CRC16) {
5405                 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5406                 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5407                 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5408
5409                 if (our_fcs != rcv_fcs)
5410                         return -EBADMSG;
5411         }
5412         return 0;
5413 }
5414
5415 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5416 {
5417         struct l2cap_ctrl control;
5418
5419         BT_DBG("chan %p", chan);
5420
5421         memset(&control, 0, sizeof(control));
5422         control.sframe = 1;
5423         control.final = 1;
5424         control.reqseq = chan->buffer_seq;
5425         set_bit(CONN_SEND_FBIT, &chan->conn_state);
5426
5427         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5428                 control.super = L2CAP_SUPER_RNR;
5429                 l2cap_send_sframe(chan, &control);
5430         }
5431
5432         if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5433             chan->unacked_frames > 0)
5434                 __set_retrans_timer(chan);
5435
5436         /* Send pending iframes */
5437         l2cap_ertm_send(chan);
5438
5439         if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5440             test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5441                 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5442                  * send it now.
5443                  */
5444                 control.super = L2CAP_SUPER_RR;
5445                 l2cap_send_sframe(chan, &control);
5446         }
5447 }
5448
5449 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5450                             struct sk_buff **last_frag)
5451 {
5452         /* skb->len reflects data in skb as well as all fragments
5453          * skb->data_len reflects only data in fragments
5454          */
5455         if (!skb_has_frag_list(skb))
5456                 skb_shinfo(skb)->frag_list = new_frag;
5457
5458         new_frag->next = NULL;
5459
5460         (*last_frag)->next = new_frag;
5461         *last_frag = new_frag;
5462
5463         skb->len += new_frag->len;
5464         skb->data_len += new_frag->len;
5465         skb->truesize += new_frag->truesize;
5466 }
5467
5468 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5469                                 struct l2cap_ctrl *control)
5470 {
5471         int err = -EINVAL;
5472
5473         switch (control->sar) {
5474         case L2CAP_SAR_UNSEGMENTED:
5475                 if (chan->sdu)
5476                         break;
5477
5478                 err = chan->ops->recv(chan, skb);
5479                 break;
5480
5481         case L2CAP_SAR_START:
5482                 if (chan->sdu)
5483                         break;
5484
5485                 chan->sdu_len = get_unaligned_le16(skb->data);
5486                 skb_pull(skb, L2CAP_SDULEN_SIZE);
5487
5488                 if (chan->sdu_len > chan->imtu) {
5489                         err = -EMSGSIZE;
5490                         break;
5491                 }
5492
5493                 if (skb->len >= chan->sdu_len)
5494                         break;
5495
5496                 chan->sdu = skb;
5497                 chan->sdu_last_frag = skb;
5498
5499                 skb = NULL;
5500                 err = 0;
5501                 break;
5502
5503         case L2CAP_SAR_CONTINUE:
5504                 if (!chan->sdu)
5505                         break;
5506
5507                 append_skb_frag(chan->sdu, skb,
5508                                 &chan->sdu_last_frag);
5509                 skb = NULL;
5510
5511                 if (chan->sdu->len >= chan->sdu_len)
5512                         break;
5513
5514                 err = 0;
5515                 break;
5516
5517         case L2CAP_SAR_END:
5518                 if (!chan->sdu)
5519                         break;
5520
5521                 append_skb_frag(chan->sdu, skb,
5522                                 &chan->sdu_last_frag);
5523                 skb = NULL;
5524
5525                 if (chan->sdu->len != chan->sdu_len)
5526                         break;
5527
5528                 err = chan->ops->recv(chan, chan->sdu);
5529
5530                 if (!err) {
5531                         /* Reassembly complete */
5532                         chan->sdu = NULL;
5533                         chan->sdu_last_frag = NULL;
5534                         chan->sdu_len = 0;
5535                 }
5536                 break;
5537         }
5538
5539         if (err) {
5540                 kfree_skb(skb);
5541                 kfree_skb(chan->sdu);
5542                 chan->sdu = NULL;
5543                 chan->sdu_last_frag = NULL;
5544                 chan->sdu_len = 0;
5545         }
5546
5547         return err;
5548 }
5549
5550 static int l2cap_resegment(struct l2cap_chan *chan)
5551 {
5552         /* Placeholder */
5553         return 0;
5554 }
5555
5556 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5557 {
5558         u8 event;
5559
5560         if (chan->mode != L2CAP_MODE_ERTM)
5561                 return;
5562
5563         event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5564         l2cap_tx(chan, NULL, NULL, event);
5565 }
5566
5567 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5568 {
5569         int err = 0;
5570         /* Pass sequential frames to l2cap_reassemble_sdu()
5571          * until a gap is encountered.
5572          */
5573
5574         BT_DBG("chan %p", chan);
5575
5576         while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5577                 struct sk_buff *skb;
5578                 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5579                        chan->buffer_seq, skb_queue_len(&chan->srej_q));
5580
5581                 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5582
5583                 if (!skb)
5584                         break;
5585
5586                 skb_unlink(skb, &chan->srej_q);
5587                 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5588                 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->control);
5589                 if (err)
5590                         break;
5591         }
5592
5593         if (skb_queue_empty(&chan->srej_q)) {
5594                 chan->rx_state = L2CAP_RX_STATE_RECV;
5595                 l2cap_send_ack(chan);
5596         }
5597
5598         return err;
5599 }
5600
5601 static void l2cap_handle_srej(struct l2cap_chan *chan,
5602                               struct l2cap_ctrl *control)
5603 {
5604         struct sk_buff *skb;
5605
5606         BT_DBG("chan %p, control %p", chan, control);
5607
5608         if (control->reqseq == chan->next_tx_seq) {
5609                 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5610                 l2cap_send_disconn_req(chan, ECONNRESET);
5611                 return;
5612         }
5613
5614         skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5615
5616         if (skb == NULL) {
5617                 BT_DBG("Seq %d not available for retransmission",
5618                        control->reqseq);
5619                 return;
5620         }
5621
5622         if (chan->max_tx != 0 && bt_cb(skb)->control.retries >= chan->max_tx) {
5623                 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5624                 l2cap_send_disconn_req(chan, ECONNRESET);
5625                 return;
5626         }
5627
5628         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5629
5630         if (control->poll) {
5631                 l2cap_pass_to_tx(chan, control);
5632
5633                 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5634                 l2cap_retransmit(chan, control);
5635                 l2cap_ertm_send(chan);
5636
5637                 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5638                         set_bit(CONN_SREJ_ACT, &chan->conn_state);
5639                         chan->srej_save_reqseq = control->reqseq;
5640                 }
5641         } else {
5642                 l2cap_pass_to_tx_fbit(chan, control);
5643
5644                 if (control->final) {
5645                         if (chan->srej_save_reqseq != control->reqseq ||
5646                             !test_and_clear_bit(CONN_SREJ_ACT,
5647                                                 &chan->conn_state))
5648                                 l2cap_retransmit(chan, control);
5649                 } else {
5650                         l2cap_retransmit(chan, control);
5651                         if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5652                                 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5653                                 chan->srej_save_reqseq = control->reqseq;
5654                         }
5655                 }
5656         }
5657 }
5658
5659 static void l2cap_handle_rej(struct l2cap_chan *chan,
5660                              struct l2cap_ctrl *control)
5661 {
5662         struct sk_buff *skb;
5663
5664         BT_DBG("chan %p, control %p", chan, control);
5665
5666         if (control->reqseq == chan->next_tx_seq) {
5667                 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5668                 l2cap_send_disconn_req(chan, ECONNRESET);
5669                 return;
5670         }
5671
5672         skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5673
5674         if (chan->max_tx && skb &&
5675             bt_cb(skb)->control.retries >= chan->max_tx) {
5676                 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5677                 l2cap_send_disconn_req(chan, ECONNRESET);
5678                 return;
5679         }
5680
5681         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5682
5683         l2cap_pass_to_tx(chan, control);
5684
5685         if (control->final) {
5686                 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
5687                         l2cap_retransmit_all(chan, control);
5688         } else {
5689                 l2cap_retransmit_all(chan, control);
5690                 l2cap_ertm_send(chan);
5691                 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
5692                         set_bit(CONN_REJ_ACT, &chan->conn_state);
5693         }
5694 }
5695
5696 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
5697 {
5698         BT_DBG("chan %p, txseq %d", chan, txseq);
5699
5700         BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
5701                chan->expected_tx_seq);
5702
5703         if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
5704                 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
5705                     chan->tx_win) {
5706                         /* See notes below regarding "double poll" and
5707                          * invalid packets.
5708                          */
5709                         if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
5710                                 BT_DBG("Invalid/Ignore - after SREJ");
5711                                 return L2CAP_TXSEQ_INVALID_IGNORE;
5712                         } else {
5713                                 BT_DBG("Invalid - in window after SREJ sent");
5714                                 return L2CAP_TXSEQ_INVALID;
5715                         }
5716                 }
5717
5718                 if (chan->srej_list.head == txseq) {
5719                         BT_DBG("Expected SREJ");
5720                         return L2CAP_TXSEQ_EXPECTED_SREJ;
5721                 }
5722
5723                 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
5724                         BT_DBG("Duplicate SREJ - txseq already stored");
5725                         return L2CAP_TXSEQ_DUPLICATE_SREJ;
5726                 }
5727
5728                 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
5729                         BT_DBG("Unexpected SREJ - not requested");
5730                         return L2CAP_TXSEQ_UNEXPECTED_SREJ;
5731                 }
5732         }
5733
5734         if (chan->expected_tx_seq == txseq) {
5735                 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
5736                     chan->tx_win) {
5737                         BT_DBG("Invalid - txseq outside tx window");
5738                         return L2CAP_TXSEQ_INVALID;
5739                 } else {
5740                         BT_DBG("Expected");
5741                         return L2CAP_TXSEQ_EXPECTED;
5742                 }
5743         }
5744
5745         if (__seq_offset(chan, txseq, chan->last_acked_seq) <
5746             __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
5747                 BT_DBG("Duplicate - expected_tx_seq later than txseq");
5748                 return L2CAP_TXSEQ_DUPLICATE;
5749         }
5750
5751         if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
5752                 /* A source of invalid packets is a "double poll" condition,
5753                  * where delays cause us to send multiple poll packets.  If
5754                  * the remote stack receives and processes both polls,
5755                  * sequence numbers can wrap around in such a way that a
5756                  * resent frame has a sequence number that looks like new data
5757                  * with a sequence gap.  This would trigger an erroneous SREJ
5758                  * request.
5759                  *
5760                  * Fortunately, this is impossible with a tx window that's
5761                  * less than half of the maximum sequence number, which allows
5762                  * invalid frames to be safely ignored.
5763                  *
5764                  * With tx window sizes greater than half of the tx window
5765                  * maximum, the frame is invalid and cannot be ignored.  This
5766                  * causes a disconnect.
5767                  */
5768
5769                 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
5770                         BT_DBG("Invalid/Ignore - txseq outside tx window");
5771                         return L2CAP_TXSEQ_INVALID_IGNORE;
5772                 } else {
5773                         BT_DBG("Invalid - txseq outside tx window");
5774                         return L2CAP_TXSEQ_INVALID;
5775                 }
5776         } else {
5777                 BT_DBG("Unexpected - txseq indicates missing frames");
5778                 return L2CAP_TXSEQ_UNEXPECTED;
5779         }
5780 }
5781
5782 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
5783                                struct l2cap_ctrl *control,
5784                                struct sk_buff *skb, u8 event)
5785 {
5786         int err = 0;
5787         bool skb_in_use = 0;
5788
5789         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
5790                event);
5791
5792         switch (event) {
5793         case L2CAP_EV_RECV_IFRAME:
5794                 switch (l2cap_classify_txseq(chan, control->txseq)) {
5795                 case L2CAP_TXSEQ_EXPECTED:
5796                         l2cap_pass_to_tx(chan, control);
5797
5798                         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5799                                 BT_DBG("Busy, discarding expected seq %d",
5800                                        control->txseq);
5801                                 break;
5802                         }
5803
5804                         chan->expected_tx_seq = __next_seq(chan,
5805                                                            control->txseq);
5806
5807                         chan->buffer_seq = chan->expected_tx_seq;
5808                         skb_in_use = 1;
5809
5810                         err = l2cap_reassemble_sdu(chan, skb, control);
5811                         if (err)
5812                                 break;
5813
5814                         if (control->final) {
5815                                 if (!test_and_clear_bit(CONN_REJ_ACT,
5816                                                         &chan->conn_state)) {
5817                                         control->final = 0;
5818                                         l2cap_retransmit_all(chan, control);
5819                                         l2cap_ertm_send(chan);
5820                                 }
5821                         }
5822
5823                         if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
5824                                 l2cap_send_ack(chan);
5825                         break;
5826                 case L2CAP_TXSEQ_UNEXPECTED:
5827                         l2cap_pass_to_tx(chan, control);
5828
5829                         /* Can't issue SREJ frames in the local busy state.
5830                          * Drop this frame, it will be seen as missing
5831                          * when local busy is exited.
5832                          */
5833                         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5834                                 BT_DBG("Busy, discarding unexpected seq %d",
5835                                        control->txseq);
5836                                 break;
5837                         }
5838
5839                         /* There was a gap in the sequence, so an SREJ
5840                          * must be sent for each missing frame.  The
5841                          * current frame is stored for later use.
5842                          */
5843                         skb_queue_tail(&chan->srej_q, skb);
5844                         skb_in_use = 1;
5845                         BT_DBG("Queued %p (queue len %d)", skb,
5846                                skb_queue_len(&chan->srej_q));
5847
5848                         clear_bit(CONN_SREJ_ACT, &chan->conn_state);
5849                         l2cap_seq_list_clear(&chan->srej_list);
5850                         l2cap_send_srej(chan, control->txseq);
5851
5852                         chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
5853                         break;
5854                 case L2CAP_TXSEQ_DUPLICATE:
5855                         l2cap_pass_to_tx(chan, control);
5856                         break;
5857                 case L2CAP_TXSEQ_INVALID_IGNORE:
5858                         break;
5859                 case L2CAP_TXSEQ_INVALID:
5860                 default:
5861                         l2cap_send_disconn_req(chan, ECONNRESET);
5862                         break;
5863                 }
5864                 break;
5865         case L2CAP_EV_RECV_RR:
5866                 l2cap_pass_to_tx(chan, control);
5867                 if (control->final) {
5868                         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5869
5870                         if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
5871                             !__chan_is_moving(chan)) {
5872                                 control->final = 0;
5873                                 l2cap_retransmit_all(chan, control);
5874                         }
5875
5876                         l2cap_ertm_send(chan);
5877                 } else if (control->poll) {
5878                         l2cap_send_i_or_rr_or_rnr(chan);
5879                 } else {
5880                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
5881                                                &chan->conn_state) &&
5882                             chan->unacked_frames)
5883                                 __set_retrans_timer(chan);
5884
5885                         l2cap_ertm_send(chan);
5886                 }
5887                 break;
5888         case L2CAP_EV_RECV_RNR:
5889                 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5890                 l2cap_pass_to_tx(chan, control);
5891                 if (control && control->poll) {
5892                         set_bit(CONN_SEND_FBIT, &chan->conn_state);
5893                         l2cap_send_rr_or_rnr(chan, 0);
5894                 }
5895                 __clear_retrans_timer(chan);
5896                 l2cap_seq_list_clear(&chan->retrans_list);
5897                 break;
5898         case L2CAP_EV_RECV_REJ:
5899                 l2cap_handle_rej(chan, control);
5900                 break;
5901         case L2CAP_EV_RECV_SREJ:
5902                 l2cap_handle_srej(chan, control);
5903                 break;
5904         default:
5905                 break;
5906         }
5907
5908         if (skb && !skb_in_use) {
5909                 BT_DBG("Freeing %p", skb);
5910                 kfree_skb(skb);
5911         }
5912
5913         return err;
5914 }
5915
5916 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
5917                                     struct l2cap_ctrl *control,
5918                                     struct sk_buff *skb, u8 event)
5919 {
5920         int err = 0;
5921         u16 txseq = control->txseq;
5922         bool skb_in_use = 0;
5923
5924         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
5925                event);
5926
5927         switch (event) {
5928         case L2CAP_EV_RECV_IFRAME:
5929                 switch (l2cap_classify_txseq(chan, txseq)) {
5930                 case L2CAP_TXSEQ_EXPECTED:
5931                         /* Keep frame for reassembly later */
5932                         l2cap_pass_to_tx(chan, control);
5933                         skb_queue_tail(&chan->srej_q, skb);
5934                         skb_in_use = 1;
5935                         BT_DBG("Queued %p (queue len %d)", skb,
5936                                skb_queue_len(&chan->srej_q));
5937
5938                         chan->expected_tx_seq = __next_seq(chan, txseq);
5939                         break;
5940                 case L2CAP_TXSEQ_EXPECTED_SREJ:
5941                         l2cap_seq_list_pop(&chan->srej_list);
5942
5943                         l2cap_pass_to_tx(chan, control);
5944                         skb_queue_tail(&chan->srej_q, skb);
5945                         skb_in_use = 1;
5946                         BT_DBG("Queued %p (queue len %d)", skb,
5947                                skb_queue_len(&chan->srej_q));
5948
5949                         err = l2cap_rx_queued_iframes(chan);
5950                         if (err)
5951                                 break;
5952
5953                         break;
5954                 case L2CAP_TXSEQ_UNEXPECTED:
5955                         /* Got a frame that can't be reassembled yet.
5956                          * Save it for later, and send SREJs to cover
5957                          * the missing frames.
5958                          */
5959                         skb_queue_tail(&chan->srej_q, skb);
5960                         skb_in_use = 1;
5961                         BT_DBG("Queued %p (queue len %d)", skb,
5962                                skb_queue_len(&chan->srej_q));
5963
5964                         l2cap_pass_to_tx(chan, control);
5965                         l2cap_send_srej(chan, control->txseq);
5966                         break;
5967                 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
5968                         /* This frame was requested with an SREJ, but
5969                          * some expected retransmitted frames are
5970                          * missing.  Request retransmission of missing
5971                          * SREJ'd frames.
5972                          */
5973                         skb_queue_tail(&chan->srej_q, skb);
5974                         skb_in_use = 1;
5975                         BT_DBG("Queued %p (queue len %d)", skb,
5976                                skb_queue_len(&chan->srej_q));
5977
5978                         l2cap_pass_to_tx(chan, control);
5979                         l2cap_send_srej_list(chan, control->txseq);
5980                         break;
5981                 case L2CAP_TXSEQ_DUPLICATE_SREJ:
5982                         /* We've already queued this frame.  Drop this copy. */
5983                         l2cap_pass_to_tx(chan, control);
5984                         break;
5985                 case L2CAP_TXSEQ_DUPLICATE:
5986                         /* Expecting a later sequence number, so this frame
5987                          * was already received.  Ignore it completely.
5988                          */
5989                         break;
5990                 case L2CAP_TXSEQ_INVALID_IGNORE:
5991                         break;
5992                 case L2CAP_TXSEQ_INVALID:
5993                 default:
5994                         l2cap_send_disconn_req(chan, ECONNRESET);
5995                         break;
5996                 }
5997                 break;
5998         case L2CAP_EV_RECV_RR:
5999                 l2cap_pass_to_tx(chan, control);
6000                 if (control->final) {
6001                         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6002
6003                         if (!test_and_clear_bit(CONN_REJ_ACT,
6004                                                 &chan->conn_state)) {
6005                                 control->final = 0;
6006                                 l2cap_retransmit_all(chan, control);
6007                         }
6008
6009                         l2cap_ertm_send(chan);
6010                 } else if (control->poll) {
6011                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
6012                                                &chan->conn_state) &&
6013                             chan->unacked_frames) {
6014                                 __set_retrans_timer(chan);
6015                         }
6016
6017                         set_bit(CONN_SEND_FBIT, &chan->conn_state);
6018                         l2cap_send_srej_tail(chan);
6019                 } else {
6020                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
6021                                                &chan->conn_state) &&
6022                             chan->unacked_frames)
6023                                 __set_retrans_timer(chan);
6024
6025                         l2cap_send_ack(chan);
6026                 }
6027                 break;
6028         case L2CAP_EV_RECV_RNR:
6029                 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6030                 l2cap_pass_to_tx(chan, control);
6031                 if (control->poll) {
6032                         l2cap_send_srej_tail(chan);
6033                 } else {
6034                         struct l2cap_ctrl rr_control;
6035                         memset(&rr_control, 0, sizeof(rr_control));
6036                         rr_control.sframe = 1;
6037                         rr_control.super = L2CAP_SUPER_RR;
6038                         rr_control.reqseq = chan->buffer_seq;
6039                         l2cap_send_sframe(chan, &rr_control);
6040                 }
6041
6042                 break;
6043         case L2CAP_EV_RECV_REJ:
6044                 l2cap_handle_rej(chan, control);
6045                 break;
6046         case L2CAP_EV_RECV_SREJ:
6047                 l2cap_handle_srej(chan, control);
6048                 break;
6049         }
6050
6051         if (skb && !skb_in_use) {
6052                 BT_DBG("Freeing %p", skb);
6053                 kfree_skb(skb);
6054         }
6055
6056         return err;
6057 }
6058
6059 static int l2cap_finish_move(struct l2cap_chan *chan)
6060 {
6061         BT_DBG("chan %p", chan);
6062
6063         chan->rx_state = L2CAP_RX_STATE_RECV;
6064
6065         if (chan->hs_hcon)
6066                 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6067         else
6068                 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6069
6070         return l2cap_resegment(chan);
6071 }
6072
6073 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6074                                  struct l2cap_ctrl *control,
6075                                  struct sk_buff *skb, u8 event)
6076 {
6077         int err;
6078
6079         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6080                event);
6081
6082         if (!control->poll)
6083                 return -EPROTO;
6084
6085         l2cap_process_reqseq(chan, control->reqseq);
6086
6087         if (!skb_queue_empty(&chan->tx_q))
6088                 chan->tx_send_head = skb_peek(&chan->tx_q);
6089         else
6090                 chan->tx_send_head = NULL;
6091
6092         /* Rewind next_tx_seq to the point expected
6093          * by the receiver.
6094          */
6095         chan->next_tx_seq = control->reqseq;
6096         chan->unacked_frames = 0;
6097
6098         err = l2cap_finish_move(chan);
6099         if (err)
6100                 return err;
6101
6102         set_bit(CONN_SEND_FBIT, &chan->conn_state);
6103         l2cap_send_i_or_rr_or_rnr(chan);
6104
6105         if (event == L2CAP_EV_RECV_IFRAME)
6106                 return -EPROTO;
6107
6108         return l2cap_rx_state_recv(chan, control, NULL, event);
6109 }
6110
6111 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6112                                  struct l2cap_ctrl *control,
6113                                  struct sk_buff *skb, u8 event)
6114 {
6115         int err;
6116
6117         if (!control->final)
6118                 return -EPROTO;
6119
6120         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6121
6122         chan->rx_state = L2CAP_RX_STATE_RECV;
6123         l2cap_process_reqseq(chan, control->reqseq);
6124
6125         if (!skb_queue_empty(&chan->tx_q))
6126                 chan->tx_send_head = skb_peek(&chan->tx_q);
6127         else
6128                 chan->tx_send_head = NULL;
6129
6130         /* Rewind next_tx_seq to the point expected
6131          * by the receiver.
6132          */
6133         chan->next_tx_seq = control->reqseq;
6134         chan->unacked_frames = 0;
6135
6136         if (chan->hs_hcon)
6137                 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6138         else
6139                 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6140
6141         err = l2cap_resegment(chan);
6142
6143         if (!err)
6144                 err = l2cap_rx_state_recv(chan, control, skb, event);
6145
6146         return err;
6147 }
6148
6149 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6150 {
6151         /* Make sure reqseq is for a packet that has been sent but not acked */
6152         u16 unacked;
6153
6154         unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6155         return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6156 }
6157
6158 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6159                     struct sk_buff *skb, u8 event)
6160 {
6161         int err = 0;
6162
6163         BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6164                control, skb, event, chan->rx_state);
6165
6166         if (__valid_reqseq(chan, control->reqseq)) {
6167                 switch (chan->rx_state) {
6168                 case L2CAP_RX_STATE_RECV:
6169                         err = l2cap_rx_state_recv(chan, control, skb, event);
6170                         break;
6171                 case L2CAP_RX_STATE_SREJ_SENT:
6172                         err = l2cap_rx_state_srej_sent(chan, control, skb,
6173                                                        event);
6174                         break;
6175                 case L2CAP_RX_STATE_WAIT_P:
6176                         err = l2cap_rx_state_wait_p(chan, control, skb, event);
6177                         break;
6178                 case L2CAP_RX_STATE_WAIT_F:
6179                         err = l2cap_rx_state_wait_f(chan, control, skb, event);
6180                         break;
6181                 default:
6182                         /* shut it down */
6183                         break;
6184                 }
6185         } else {
6186                 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6187                        control->reqseq, chan->next_tx_seq,
6188                        chan->expected_ack_seq);
6189                 l2cap_send_disconn_req(chan, ECONNRESET);
6190         }
6191
6192         return err;
6193 }
6194
6195 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6196                            struct sk_buff *skb)
6197 {
6198         int err = 0;
6199
6200         BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6201                chan->rx_state);
6202
6203         if (l2cap_classify_txseq(chan, control->txseq) ==
6204             L2CAP_TXSEQ_EXPECTED) {
6205                 l2cap_pass_to_tx(chan, control);
6206
6207                 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6208                        __next_seq(chan, chan->buffer_seq));
6209
6210                 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6211
6212                 l2cap_reassemble_sdu(chan, skb, control);
6213         } else {
6214                 if (chan->sdu) {
6215                         kfree_skb(chan->sdu);
6216                         chan->sdu = NULL;
6217                 }
6218                 chan->sdu_last_frag = NULL;
6219                 chan->sdu_len = 0;
6220
6221                 if (skb) {
6222                         BT_DBG("Freeing %p", skb);
6223                         kfree_skb(skb);
6224                 }
6225         }
6226
6227         chan->last_acked_seq = control->txseq;
6228         chan->expected_tx_seq = __next_seq(chan, control->txseq);
6229
6230         return err;
6231 }
6232
6233 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6234 {
6235         struct l2cap_ctrl *control = &bt_cb(skb)->control;
6236         u16 len;
6237         u8 event;
6238
6239         __unpack_control(chan, skb);
6240
6241         len = skb->len;
6242
6243         /*
6244          * We can just drop the corrupted I-frame here.
6245          * Receiver will miss it and start proper recovery
6246          * procedures and ask for retransmission.
6247          */
6248         if (l2cap_check_fcs(chan, skb))
6249                 goto drop;
6250
6251         if (!control->sframe && control->sar == L2CAP_SAR_START)
6252                 len -= L2CAP_SDULEN_SIZE;
6253
6254         if (chan->fcs == L2CAP_FCS_CRC16)
6255                 len -= L2CAP_FCS_SIZE;
6256
6257         if (len > chan->mps) {
6258                 l2cap_send_disconn_req(chan, ECONNRESET);
6259                 goto drop;
6260         }
6261
6262         if (!control->sframe) {
6263                 int err;
6264
6265                 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6266                        control->sar, control->reqseq, control->final,
6267                        control->txseq);
6268
6269                 /* Validate F-bit - F=0 always valid, F=1 only
6270                  * valid in TX WAIT_F
6271                  */
6272                 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6273                         goto drop;
6274
6275                 if (chan->mode != L2CAP_MODE_STREAMING) {
6276                         event = L2CAP_EV_RECV_IFRAME;
6277                         err = l2cap_rx(chan, control, skb, event);
6278                 } else {
6279                         err = l2cap_stream_rx(chan, control, skb);
6280                 }
6281
6282                 if (err)
6283                         l2cap_send_disconn_req(chan, ECONNRESET);
6284         } else {
6285                 const u8 rx_func_to_event[4] = {
6286                         L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6287                         L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6288                 };
6289
6290                 /* Only I-frames are expected in streaming mode */
6291                 if (chan->mode == L2CAP_MODE_STREAMING)
6292                         goto drop;
6293
6294                 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6295                        control->reqseq, control->final, control->poll,
6296                        control->super);
6297
6298                 if (len != 0) {
6299                         BT_ERR("Trailing bytes: %d in sframe", len);
6300                         l2cap_send_disconn_req(chan, ECONNRESET);
6301                         goto drop;
6302                 }
6303
6304                 /* Validate F and P bits */
6305                 if (control->final && (control->poll ||
6306                                        chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6307                         goto drop;
6308
6309                 event = rx_func_to_event[control->super];
6310                 if (l2cap_rx(chan, control, skb, event))
6311                         l2cap_send_disconn_req(chan, ECONNRESET);
6312         }
6313
6314         return 0;
6315
6316 drop:
6317         kfree_skb(skb);
6318         return 0;
6319 }
6320
6321 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6322                                struct sk_buff *skb)
6323 {
6324         struct l2cap_chan *chan;
6325
6326         chan = l2cap_get_chan_by_scid(conn, cid);
6327         if (!chan) {
6328                 if (cid == L2CAP_CID_A2MP) {
6329                         chan = a2mp_channel_create(conn, skb);
6330                         if (!chan) {
6331                                 kfree_skb(skb);
6332                                 return;
6333                         }
6334
6335                         l2cap_chan_lock(chan);
6336                 } else {
6337                         BT_DBG("unknown cid 0x%4.4x", cid);
6338                         /* Drop packet and return */
6339                         kfree_skb(skb);
6340                         return;
6341                 }
6342         }
6343
6344         BT_DBG("chan %p, len %d", chan, skb->len);
6345
6346         if (chan->state != BT_CONNECTED)
6347                 goto drop;
6348
6349         switch (chan->mode) {
6350         case L2CAP_MODE_BASIC:
6351                 /* If socket recv buffers overflows we drop data here
6352                  * which is *bad* because L2CAP has to be reliable.
6353                  * But we don't have any other choice. L2CAP doesn't
6354                  * provide flow control mechanism. */
6355
6356                 if (chan->imtu < skb->len)
6357                         goto drop;
6358
6359                 if (!chan->ops->recv(chan, skb))
6360                         goto done;
6361                 break;
6362
6363         case L2CAP_MODE_ERTM:
6364         case L2CAP_MODE_STREAMING:
6365                 l2cap_data_rcv(chan, skb);
6366                 goto done;
6367
6368         default:
6369                 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6370                 break;
6371         }
6372
6373 drop:
6374         kfree_skb(skb);
6375
6376 done:
6377         l2cap_chan_unlock(chan);
6378 }
6379
6380 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6381                                   struct sk_buff *skb)
6382 {
6383         struct l2cap_chan *chan;
6384
6385         chan = l2cap_global_chan_by_psm(0, psm, conn->src, conn->dst);
6386         if (!chan)
6387                 goto drop;
6388
6389         BT_DBG("chan %p, len %d", chan, skb->len);
6390
6391         if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6392                 goto drop;
6393
6394         if (chan->imtu < skb->len)
6395                 goto drop;
6396
6397         if (!chan->ops->recv(chan, skb))
6398                 return;
6399
6400 drop:
6401         kfree_skb(skb);
6402 }
6403
6404 static void l2cap_att_channel(struct l2cap_conn *conn,
6405                               struct sk_buff *skb)
6406 {
6407         struct l2cap_chan *chan;
6408
6409         chan = l2cap_global_chan_by_scid(BT_CONNECTED, L2CAP_CID_ATT,
6410                                          conn->src, conn->dst);
6411         if (!chan)
6412                 goto drop;
6413
6414         BT_DBG("chan %p, len %d", chan, skb->len);
6415
6416         if (chan->imtu < skb->len)
6417                 goto drop;
6418
6419         if (!chan->ops->recv(chan, skb))
6420                 return;
6421
6422 drop:
6423         kfree_skb(skb);
6424 }
6425
6426 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6427 {
6428         struct l2cap_hdr *lh = (void *) skb->data;
6429         u16 cid, len;
6430         __le16 psm;
6431
6432         skb_pull(skb, L2CAP_HDR_SIZE);
6433         cid = __le16_to_cpu(lh->cid);
6434         len = __le16_to_cpu(lh->len);
6435
6436         if (len != skb->len) {
6437                 kfree_skb(skb);
6438                 return;
6439         }
6440
6441         BT_DBG("len %d, cid 0x%4.4x", len, cid);
6442
6443         switch (cid) {
6444         case L2CAP_CID_LE_SIGNALING:
6445                 l2cap_le_sig_channel(conn, skb);
6446                 break;
6447         case L2CAP_CID_SIGNALING:
6448                 l2cap_sig_channel(conn, skb);
6449                 break;
6450
6451         case L2CAP_CID_CONN_LESS:
6452                 psm = get_unaligned((__le16 *) skb->data);
6453                 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6454                 l2cap_conless_channel(conn, psm, skb);
6455                 break;
6456
6457         case L2CAP_CID_ATT:
6458                 l2cap_att_channel(conn, skb);
6459                 break;
6460
6461         case L2CAP_CID_SMP:
6462                 if (smp_sig_channel(conn, skb))
6463                         l2cap_conn_del(conn->hcon, EACCES);
6464                 break;
6465
6466         default:
6467                 l2cap_data_channel(conn, cid, skb);
6468                 break;
6469         }
6470 }
6471
6472 /* ---- L2CAP interface with lower layer (HCI) ---- */
6473
6474 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
6475 {
6476         int exact = 0, lm1 = 0, lm2 = 0;
6477         struct l2cap_chan *c;
6478
6479         BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
6480
6481         /* Find listening sockets and check their link_mode */
6482         read_lock(&chan_list_lock);
6483         list_for_each_entry(c, &chan_list, global_l) {
6484                 struct sock *sk = c->sk;
6485
6486                 if (c->state != BT_LISTEN)
6487                         continue;
6488
6489                 if (!bacmp(&bt_sk(sk)->src, &hdev->bdaddr)) {
6490                         lm1 |= HCI_LM_ACCEPT;
6491                         if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
6492                                 lm1 |= HCI_LM_MASTER;
6493                         exact++;
6494                 } else if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY)) {
6495                         lm2 |= HCI_LM_ACCEPT;
6496                         if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
6497                                 lm2 |= HCI_LM_MASTER;
6498                 }
6499         }
6500         read_unlock(&chan_list_lock);
6501
6502         return exact ? lm1 : lm2;
6503 }
6504
6505 void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
6506 {
6507         struct l2cap_conn *conn;
6508
6509         BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
6510
6511         if (!status) {
6512                 conn = l2cap_conn_add(hcon);
6513                 if (conn)
6514                         l2cap_conn_ready(conn);
6515         } else {
6516                 l2cap_conn_del(hcon, bt_to_errno(status));
6517         }
6518 }
6519
6520 int l2cap_disconn_ind(struct hci_conn *hcon)
6521 {
6522         struct l2cap_conn *conn = hcon->l2cap_data;
6523
6524         BT_DBG("hcon %p", hcon);
6525
6526         if (!conn)
6527                 return HCI_ERROR_REMOTE_USER_TERM;
6528         return conn->disc_reason;
6529 }
6530
6531 void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
6532 {
6533         BT_DBG("hcon %p reason %d", hcon, reason);
6534
6535         l2cap_conn_del(hcon, bt_to_errno(reason));
6536 }
6537
6538 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
6539 {
6540         if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
6541                 return;
6542
6543         if (encrypt == 0x00) {
6544                 if (chan->sec_level == BT_SECURITY_MEDIUM) {
6545                         __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
6546                 } else if (chan->sec_level == BT_SECURITY_HIGH)
6547                         l2cap_chan_close(chan, ECONNREFUSED);
6548         } else {
6549                 if (chan->sec_level == BT_SECURITY_MEDIUM)
6550                         __clear_chan_timer(chan);
6551         }
6552 }
6553
6554 int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
6555 {
6556         struct l2cap_conn *conn = hcon->l2cap_data;
6557         struct l2cap_chan *chan;
6558
6559         if (!conn)
6560                 return 0;
6561
6562         BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
6563
6564         if (hcon->type == LE_LINK) {
6565                 if (!status && encrypt)
6566                         smp_distribute_keys(conn, 0);
6567                 cancel_delayed_work(&conn->security_timer);
6568         }
6569
6570         mutex_lock(&conn->chan_lock);
6571
6572         list_for_each_entry(chan, &conn->chan_l, list) {
6573                 l2cap_chan_lock(chan);
6574
6575                 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
6576                        state_to_string(chan->state));
6577
6578                 if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
6579                         l2cap_chan_unlock(chan);
6580                         continue;
6581                 }
6582
6583                 if (chan->scid == L2CAP_CID_ATT) {
6584                         if (!status && encrypt) {
6585                                 chan->sec_level = hcon->sec_level;
6586                                 l2cap_chan_ready(chan);
6587                         }
6588
6589                         l2cap_chan_unlock(chan);
6590                         continue;
6591                 }
6592
6593                 if (!__l2cap_no_conn_pending(chan)) {
6594                         l2cap_chan_unlock(chan);
6595                         continue;
6596                 }
6597
6598                 if (!status && (chan->state == BT_CONNECTED ||
6599                                 chan->state == BT_CONFIG)) {
6600                         struct sock *sk = chan->sk;
6601
6602                         clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
6603                         sk->sk_state_change(sk);
6604
6605                         l2cap_check_encryption(chan, encrypt);
6606                         l2cap_chan_unlock(chan);
6607                         continue;
6608                 }
6609
6610                 if (chan->state == BT_CONNECT) {
6611                         if (!status) {
6612                                 l2cap_start_connection(chan);
6613                         } else {
6614                                 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
6615                         }
6616                 } else if (chan->state == BT_CONNECT2) {
6617                         struct sock *sk = chan->sk;
6618                         struct l2cap_conn_rsp rsp;
6619                         __u16 res, stat;
6620
6621                         lock_sock(sk);
6622
6623                         if (!status) {
6624                                 if (test_bit(BT_SK_DEFER_SETUP,
6625                                              &bt_sk(sk)->flags)) {
6626                                         res = L2CAP_CR_PEND;
6627                                         stat = L2CAP_CS_AUTHOR_PEND;
6628                                         chan->ops->defer(chan);
6629                                 } else {
6630                                         __l2cap_state_change(chan, BT_CONFIG);
6631                                         res = L2CAP_CR_SUCCESS;
6632                                         stat = L2CAP_CS_NO_INFO;
6633                                 }
6634                         } else {
6635                                 __l2cap_state_change(chan, BT_DISCONN);
6636                                 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
6637                                 res = L2CAP_CR_SEC_BLOCK;
6638                                 stat = L2CAP_CS_NO_INFO;
6639                         }
6640
6641                         release_sock(sk);
6642
6643                         rsp.scid   = cpu_to_le16(chan->dcid);
6644                         rsp.dcid   = cpu_to_le16(chan->scid);
6645                         rsp.result = cpu_to_le16(res);
6646                         rsp.status = cpu_to_le16(stat);
6647                         l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
6648                                        sizeof(rsp), &rsp);
6649
6650                         if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
6651                             res == L2CAP_CR_SUCCESS) {
6652                                 char buf[128];
6653                                 set_bit(CONF_REQ_SENT, &chan->conf_state);
6654                                 l2cap_send_cmd(conn, l2cap_get_ident(conn),
6655                                                L2CAP_CONF_REQ,
6656                                                l2cap_build_conf_req(chan, buf),
6657                                                buf);
6658                                 chan->num_conf_req++;
6659                         }
6660                 }
6661
6662                 l2cap_chan_unlock(chan);
6663         }
6664
6665         mutex_unlock(&conn->chan_lock);
6666
6667         return 0;
6668 }
6669
6670 int l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
6671 {
6672         struct l2cap_conn *conn = hcon->l2cap_data;
6673         struct l2cap_hdr *hdr;
6674         int len;
6675
6676         /* For AMP controller do not create l2cap conn */
6677         if (!conn && hcon->hdev->dev_type != HCI_BREDR)
6678                 goto drop;
6679
6680         if (!conn)
6681                 conn = l2cap_conn_add(hcon);
6682
6683         if (!conn)
6684                 goto drop;
6685
6686         BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
6687
6688         switch (flags) {
6689         case ACL_START:
6690         case ACL_START_NO_FLUSH:
6691         case ACL_COMPLETE:
6692                 if (conn->rx_len) {
6693                         BT_ERR("Unexpected start frame (len %d)", skb->len);
6694                         kfree_skb(conn->rx_skb);
6695                         conn->rx_skb = NULL;
6696                         conn->rx_len = 0;
6697                         l2cap_conn_unreliable(conn, ECOMM);
6698                 }
6699
6700                 /* Start fragment always begin with Basic L2CAP header */
6701                 if (skb->len < L2CAP_HDR_SIZE) {
6702                         BT_ERR("Frame is too short (len %d)", skb->len);
6703                         l2cap_conn_unreliable(conn, ECOMM);
6704                         goto drop;
6705                 }
6706
6707                 hdr = (struct l2cap_hdr *) skb->data;
6708                 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
6709
6710                 if (len == skb->len) {
6711                         /* Complete frame received */
6712                         l2cap_recv_frame(conn, skb);
6713                         return 0;
6714                 }
6715
6716                 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
6717
6718                 if (skb->len > len) {
6719                         BT_ERR("Frame is too long (len %d, expected len %d)",
6720                                skb->len, len);
6721                         l2cap_conn_unreliable(conn, ECOMM);
6722                         goto drop;
6723                 }
6724
6725                 /* Allocate skb for the complete frame (with header) */
6726                 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
6727                 if (!conn->rx_skb)
6728                         goto drop;
6729
6730                 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
6731                                           skb->len);
6732                 conn->rx_len = len - skb->len;
6733                 break;
6734
6735         case ACL_CONT:
6736                 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
6737
6738                 if (!conn->rx_len) {
6739                         BT_ERR("Unexpected continuation frame (len %d)", skb->len);
6740                         l2cap_conn_unreliable(conn, ECOMM);
6741                         goto drop;
6742                 }
6743
6744                 if (skb->len > conn->rx_len) {
6745                         BT_ERR("Fragment is too long (len %d, expected %d)",
6746                                skb->len, conn->rx_len);
6747                         kfree_skb(conn->rx_skb);
6748                         conn->rx_skb = NULL;
6749                         conn->rx_len = 0;
6750                         l2cap_conn_unreliable(conn, ECOMM);
6751                         goto drop;
6752                 }
6753
6754                 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
6755                                           skb->len);
6756                 conn->rx_len -= skb->len;
6757
6758                 if (!conn->rx_len) {
6759                         /* Complete frame received */
6760                         l2cap_recv_frame(conn, conn->rx_skb);
6761                         conn->rx_skb = NULL;
6762                 }
6763                 break;
6764         }
6765
6766 drop:
6767         kfree_skb(skb);
6768         return 0;
6769 }
6770
6771 static int l2cap_debugfs_show(struct seq_file *f, void *p)
6772 {
6773         struct l2cap_chan *c;
6774
6775         read_lock(&chan_list_lock);
6776
6777         list_for_each_entry(c, &chan_list, global_l) {
6778                 struct sock *sk = c->sk;
6779
6780                 seq_printf(f, "%pMR %pMR %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
6781                            &bt_sk(sk)->src, &bt_sk(sk)->dst,
6782                            c->state, __le16_to_cpu(c->psm),
6783                            c->scid, c->dcid, c->imtu, c->omtu,
6784                            c->sec_level, c->mode);
6785         }
6786
6787         read_unlock(&chan_list_lock);
6788
6789         return 0;
6790 }
6791
6792 static int l2cap_debugfs_open(struct inode *inode, struct file *file)
6793 {
6794         return single_open(file, l2cap_debugfs_show, inode->i_private);
6795 }
6796
6797 static const struct file_operations l2cap_debugfs_fops = {
6798         .open           = l2cap_debugfs_open,
6799         .read           = seq_read,
6800         .llseek         = seq_lseek,
6801         .release        = single_release,
6802 };
6803
6804 static struct dentry *l2cap_debugfs;
6805
6806 int __init l2cap_init(void)
6807 {
6808         int err;
6809
6810         err = l2cap_init_sockets();
6811         if (err < 0)
6812                 return err;
6813
6814         if (bt_debugfs) {
6815                 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
6816                                                     NULL, &l2cap_debugfs_fops);
6817                 if (!l2cap_debugfs)
6818                         BT_ERR("Failed to create L2CAP debug file");
6819         }
6820
6821         return 0;
6822 }
6823
6824 void l2cap_exit(void)
6825 {
6826         debugfs_remove(l2cap_debugfs);
6827         l2cap_cleanup_sockets();
6828 }
6829
6830 module_param(disable_ertm, bool, 0644);
6831 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");