Pileus Git - ~andy/linux/blob - 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         bacpy(&bt_sk(sk)->src, conn->src);
3759         bacpy(&bt_sk(sk)->dst, conn->dst);
3760         chan->psm  = psm;
3761         chan->dcid = scid;
3762         chan->local_amp_id = amp_id;
3763
3764         __l2cap_chan_add(conn, chan);
3765
3766         dcid = chan->scid;
3767
3768         __set_chan_timer(chan, sk->sk_sndtimeo);
3769
3770         chan->ident = cmd->ident;
3771
3772         if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3773                 if (l2cap_chan_check_security(chan)) {
3774                         if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
3775                                 __l2cap_state_change(chan, BT_CONNECT2);
3776                                 result = L2CAP_CR_PEND;
3777                                 status = L2CAP_CS_AUTHOR_PEND;
3778                                 chan->ops->defer(chan);
3779                         } else {
3780                                 /* Force pending result for AMP controllers.
3781                                  * The connection will succeed after the
3782                                  * physical link is up.
3783                                  */
3784                                 if (amp_id) {
3785                                         __l2cap_state_change(chan, BT_CONNECT2);
3786                                         result = L2CAP_CR_PEND;
3787                                 } else {
3788                                         __l2cap_state_change(chan, BT_CONFIG);
3789                                         result = L2CAP_CR_SUCCESS;
3790                                 }
3791                                 status = L2CAP_CS_NO_INFO;
3792                         }
3793                 } else {
3794                         __l2cap_state_change(chan, BT_CONNECT2);
3795                         result = L2CAP_CR_PEND;
3796                         status = L2CAP_CS_AUTHEN_PEND;
3797                 }
3798         } else {
3799                 __l2cap_state_change(chan, BT_CONNECT2);
3800                 result = L2CAP_CR_PEND;
3801                 status = L2CAP_CS_NO_INFO;
3802         }
3803
3804 response:
3805         release_sock(parent);
3806         mutex_unlock(&conn->chan_lock);
3807
3808 sendresp:
3809         rsp.scid   = cpu_to_le16(scid);
3810         rsp.dcid   = cpu_to_le16(dcid);
3811         rsp.result = cpu_to_le16(result);
3812         rsp.status = cpu_to_le16(status);
3813         l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3814
3815         if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3816                 struct l2cap_info_req info;
3817                 info.type = __constant_cpu_to_le16(L2CAP_IT_FEAT_MASK);
3818
3819                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3820                 conn->info_ident = l2cap_get_ident(conn);
3821
3822                 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3823
3824                 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3825                                sizeof(info), &info);
3826         }
3827
3828         if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3829             result == L2CAP_CR_SUCCESS) {
3830                 u8 buf[128];
3831                 set_bit(CONF_REQ_SENT, &chan->conf_state);
3832                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3833                                l2cap_build_conf_req(chan, buf), buf);
3834                 chan->num_conf_req++;
3835         }
3836
3837         return chan;
3838 }
3839
3840 static int l2cap_connect_req(struct l2cap_conn *conn,
3841                              struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3842 {
3843         struct hci_dev *hdev = conn->hcon->hdev;
3844         struct hci_conn *hcon = conn->hcon;
3845
3846         if (cmd_len < sizeof(struct l2cap_conn_req))
3847                 return -EPROTO;
3848
3849         hci_dev_lock(hdev);
3850         if (test_bit(HCI_MGMT, &hdev->dev_flags) &&
3851             !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3852                 mgmt_device_connected(hdev, &hcon->dst, hcon->type,
3853                                       hcon->dst_type, 0, NULL, 0,
3854                                       hcon->dev_class);
3855         hci_dev_unlock(hdev);
3856
3857         l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3858         return 0;
3859 }
3860
3861 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3862                                     struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3863                                     u8 *data)
3864 {
3865         struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3866         u16 scid, dcid, result, status;
3867         struct l2cap_chan *chan;
3868         u8 req[128];
3869         int err;
3870
3871         if (cmd_len < sizeof(*rsp))
3872                 return -EPROTO;
3873
3874         scid   = __le16_to_cpu(rsp->scid);
3875         dcid   = __le16_to_cpu(rsp->dcid);
3876         result = __le16_to_cpu(rsp->result);
3877         status = __le16_to_cpu(rsp->status);
3878
3879         BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3880                dcid, scid, result, status);
3881
3882         mutex_lock(&conn->chan_lock);
3883
3884         if (scid) {
3885                 chan = __l2cap_get_chan_by_scid(conn, scid);
3886                 if (!chan) {
3887                         err = -EFAULT;
3888                         goto unlock;
3889                 }
3890         } else {
3891                 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3892                 if (!chan) {
3893                         err = -EFAULT;
3894                         goto unlock;
3895                 }
3896         }
3897
3898         err = 0;
3899
3900         l2cap_chan_lock(chan);
3901
3902         switch (result) {
3903         case L2CAP_CR_SUCCESS:
3904                 l2cap_state_change(chan, BT_CONFIG);
3905                 chan->ident = 0;
3906                 chan->dcid = dcid;
3907                 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3908
3909                 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3910                         break;
3911
3912                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3913                                l2cap_build_conf_req(chan, req), req);
3914                 chan->num_conf_req++;
3915                 break;
3916
3917         case L2CAP_CR_PEND:
3918                 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3919                 break;
3920
3921         default:
3922                 l2cap_chan_del(chan, ECONNREFUSED);
3923                 break;
3924         }
3925
3926         l2cap_chan_unlock(chan);
3927
3928 unlock:
3929         mutex_unlock(&conn->chan_lock);
3930
3931         return err;
3932 }
3933
3934 static inline void set_default_fcs(struct l2cap_chan *chan)
3935 {
3936         /* FCS is enabled only in ERTM or streaming mode, if one or both
3937          * sides request it.
3938          */
3939         if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3940                 chan->fcs = L2CAP_FCS_NONE;
3941         else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
3942                 chan->fcs = L2CAP_FCS_CRC16;
3943 }
3944
3945 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
3946                                     u8 ident, u16 flags)
3947 {
3948         struct l2cap_conn *conn = chan->conn;
3949
3950         BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
3951                flags);
3952
3953         clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3954         set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3955
3956         l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
3957                        l2cap_build_conf_rsp(chan, data,
3958                                             L2CAP_CONF_SUCCESS, flags), data);
3959 }
3960
3961 static inline int l2cap_config_req(struct l2cap_conn *conn,
3962                                    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3963                                    u8 *data)
3964 {
3965         struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
3966         u16 dcid, flags;
3967         u8 rsp[64];
3968         struct l2cap_chan *chan;
3969         int len, err = 0;
3970
3971         if (cmd_len < sizeof(*req))
3972                 return -EPROTO;
3973
3974         dcid  = __le16_to_cpu(req->dcid);
3975         flags = __le16_to_cpu(req->flags);
3976
3977         BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
3978
3979         chan = l2cap_get_chan_by_scid(conn, dcid);
3980         if (!chan)
3981                 return -ENOENT;
3982
3983         if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
3984                 struct l2cap_cmd_rej_cid rej;
3985
3986                 rej.reason = __constant_cpu_to_le16(L2CAP_REJ_INVALID_CID);
3987                 rej.scid = cpu_to_le16(chan->scid);
3988                 rej.dcid = cpu_to_le16(chan->dcid);
3989
3990                 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
3991                                sizeof(rej), &rej);
3992                 goto unlock;
3993         }
3994
3995         /* Reject if config buffer is too small. */
3996         len = cmd_len - sizeof(*req);
3997         if (chan->conf_len + len > sizeof(chan->conf_req)) {
3998                 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3999                                l2cap_build_conf_rsp(chan, rsp,
4000                                L2CAP_CONF_REJECT, flags), rsp);
4001                 goto unlock;
4002         }
4003
4004         /* Store config. */
4005         memcpy(chan->conf_req + chan->conf_len, req->data, len);
4006         chan->conf_len += len;
4007
4008         if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4009                 /* Incomplete config. Send empty response. */
4010                 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4011                                l2cap_build_conf_rsp(chan, rsp,
4012                                L2CAP_CONF_SUCCESS, flags), rsp);
4013                 goto unlock;
4014         }
4015
4016         /* Complete config. */
4017         len = l2cap_parse_conf_req(chan, rsp);
4018         if (len < 0) {
4019                 l2cap_send_disconn_req(chan, ECONNRESET);
4020                 goto unlock;
4021         }
4022
4023         chan->ident = cmd->ident;
4024         l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4025         chan->num_conf_rsp++;
4026
4027         /* Reset config buffer. */
4028         chan->conf_len = 0;
4029
4030         if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4031                 goto unlock;
4032
4033         if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4034                 set_default_fcs(chan);
4035
4036                 if (chan->mode == L2CAP_MODE_ERTM ||
4037                     chan->mode == L2CAP_MODE_STREAMING)
4038                         err = l2cap_ertm_init(chan);
4039
4040                 if (err < 0)
4041                         l2cap_send_disconn_req(chan, -err);
4042                 else
4043                         l2cap_chan_ready(chan);
4044
4045                 goto unlock;
4046         }
4047
4048         if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4049                 u8 buf[64];
4050                 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4051                                l2cap_build_conf_req(chan, buf), buf);
4052                 chan->num_conf_req++;
4053         }
4054
4055         /* Got Conf Rsp PENDING from remote side and asume we sent
4056            Conf Rsp PENDING in the code above */
4057         if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4058             test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4059
4060                 /* check compatibility */
4061
4062                 /* Send rsp for BR/EDR channel */
4063                 if (!chan->hs_hcon)
4064                         l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4065                 else
4066                         chan->ident = cmd->ident;
4067         }
4068
4069 unlock:
4070         l2cap_chan_unlock(chan);
4071         return err;
4072 }
4073
4074 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4075                                    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4076                                    u8 *data)
4077 {
4078         struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4079         u16 scid, flags, result;
4080         struct l2cap_chan *chan;
4081         int len = cmd_len - sizeof(*rsp);
4082         int err = 0;
4083
4084         if (cmd_len < sizeof(*rsp))
4085                 return -EPROTO;
4086
4087         scid   = __le16_to_cpu(rsp->scid);
4088         flags  = __le16_to_cpu(rsp->flags);
4089         result = __le16_to_cpu(rsp->result);
4090
4091         BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4092                result, len);
4093
4094         chan = l2cap_get_chan_by_scid(conn, scid);
4095         if (!chan)
4096                 return 0;
4097
4098         switch (result) {
4099         case L2CAP_CONF_SUCCESS:
4100                 l2cap_conf_rfc_get(chan, rsp->data, len);
4101                 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4102                 break;
4103
4104         case L2CAP_CONF_PENDING:
4105                 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4106
4107                 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4108                         char buf[64];
4109
4110                         len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4111                                                    buf, &result);
4112                         if (len < 0) {
4113                                 l2cap_send_disconn_req(chan, ECONNRESET);
4114                                 goto done;
4115                         }
4116
4117                         if (!chan->hs_hcon) {
4118                                 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4119                                                         0);
4120                         } else {
4121                                 if (l2cap_check_efs(chan)) {
4122                                         amp_create_logical_link(chan);
4123                                         chan->ident = cmd->ident;
4124                                 }
4125                         }
4126                 }
4127                 goto done;
4128
4129         case L2CAP_CONF_UNACCEPT:
4130                 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4131                         char req[64];
4132
4133                         if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4134                                 l2cap_send_disconn_req(chan, ECONNRESET);
4135                                 goto done;
4136                         }
4137
4138                         /* throw out any old stored conf requests */
4139                         result = L2CAP_CONF_SUCCESS;
4140                         len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4141                                                    req, &result);
4142                         if (len < 0) {
4143                                 l2cap_send_disconn_req(chan, ECONNRESET);
4144                                 goto done;
4145                         }
4146
4147                         l2cap_send_cmd(conn, l2cap_get_ident(conn),
4148                                        L2CAP_CONF_REQ, len, req);
4149                         chan->num_conf_req++;
4150                         if (result != L2CAP_CONF_SUCCESS)
4151                                 goto done;
4152                         break;
4153                 }
4154
4155         default:
4156                 l2cap_chan_set_err(chan, ECONNRESET);
4157
4158                 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4159                 l2cap_send_disconn_req(chan, ECONNRESET);
4160                 goto done;
4161         }
4162
4163         if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4164                 goto done;
4165
4166         set_bit(CONF_INPUT_DONE, &chan->conf_state);
4167
4168         if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4169                 set_default_fcs(chan);
4170
4171                 if (chan->mode == L2CAP_MODE_ERTM ||
4172                     chan->mode == L2CAP_MODE_STREAMING)
4173                         err = l2cap_ertm_init(chan);
4174
4175                 if (err < 0)
4176                         l2cap_send_disconn_req(chan, -err);
4177                 else
4178                         l2cap_chan_ready(chan);
4179         }
4180
4181 done:
4182         l2cap_chan_unlock(chan);
4183         return err;
4184 }
4185
4186 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4187                                        struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4188                                        u8 *data)
4189 {
4190         struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4191         struct l2cap_disconn_rsp rsp;
4192         u16 dcid, scid;
4193         struct l2cap_chan *chan;
4194         struct sock *sk;
4195
4196         if (cmd_len != sizeof(*req))
4197                 return -EPROTO;
4198
4199         scid = __le16_to_cpu(req->scid);
4200         dcid = __le16_to_cpu(req->dcid);
4201
4202         BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4203
4204         mutex_lock(&conn->chan_lock);
4205
4206         chan = __l2cap_get_chan_by_scid(conn, dcid);
4207         if (!chan) {
4208                 mutex_unlock(&conn->chan_lock);
4209                 return 0;
4210         }
4211
4212         l2cap_chan_lock(chan);
4213
4214         sk = chan->sk;
4215
4216         rsp.dcid = cpu_to_le16(chan->scid);
4217         rsp.scid = cpu_to_le16(chan->dcid);
4218         l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4219
4220         lock_sock(sk);
4221         sk->sk_shutdown = SHUTDOWN_MASK;
4222         release_sock(sk);
4223
4224         l2cap_chan_hold(chan);
4225         l2cap_chan_del(chan, ECONNRESET);
4226
4227         l2cap_chan_unlock(chan);
4228
4229         chan->ops->close(chan);
4230         l2cap_chan_put(chan);
4231
4232         mutex_unlock(&conn->chan_lock);
4233
4234         return 0;
4235 }
4236
4237 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4238                                        struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4239                                        u8 *data)
4240 {
4241         struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4242         u16 dcid, scid;
4243         struct l2cap_chan *chan;
4244
4245         if (cmd_len != sizeof(*rsp))
4246                 return -EPROTO;
4247
4248         scid = __le16_to_cpu(rsp->scid);
4249         dcid = __le16_to_cpu(rsp->dcid);
4250
4251         BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4252
4253         mutex_lock(&conn->chan_lock);
4254
4255         chan = __l2cap_get_chan_by_scid(conn, scid);
4256         if (!chan) {
4257                 mutex_unlock(&conn->chan_lock);
4258                 return 0;
4259         }
4260
4261         l2cap_chan_lock(chan);
4262
4263         l2cap_chan_hold(chan);
4264         l2cap_chan_del(chan, 0);
4265
4266         l2cap_chan_unlock(chan);
4267
4268         chan->ops->close(chan);
4269         l2cap_chan_put(chan);
4270
4271         mutex_unlock(&conn->chan_lock);
4272
4273         return 0;
4274 }
4275
4276 static inline int l2cap_information_req(struct l2cap_conn *conn,
4277                                         struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4278                                         u8 *data)
4279 {
4280         struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4281         u16 type;
4282
4283         if (cmd_len != sizeof(*req))
4284                 return -EPROTO;
4285
4286         type = __le16_to_cpu(req->type);
4287
4288         BT_DBG("type 0x%4.4x", type);
4289
4290         if (type == L2CAP_IT_FEAT_MASK) {
4291                 u8 buf[8];
4292                 u32 feat_mask = l2cap_feat_mask;
4293                 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4294                 rsp->type   = __constant_cpu_to_le16(L2CAP_IT_FEAT_MASK);
4295                 rsp->result = __constant_cpu_to_le16(L2CAP_IR_SUCCESS);
4296                 if (!disable_ertm)
4297                         feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4298                                 | L2CAP_FEAT_FCS;
4299                 if (enable_hs)
4300                         feat_mask |= L2CAP_FEAT_EXT_FLOW
4301                                 | L2CAP_FEAT_EXT_WINDOW;
4302
4303                 put_unaligned_le32(feat_mask, rsp->data);
4304                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4305                                buf);
4306         } else if (type == L2CAP_IT_FIXED_CHAN) {
4307                 u8 buf[12];
4308                 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4309
4310                 if (enable_hs)
4311                         l2cap_fixed_chan[0] |= L2CAP_FC_A2MP;
4312                 else
4313                         l2cap_fixed_chan[0] &= ~L2CAP_FC_A2MP;
4314
4315                 rsp->type   = __constant_cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4316                 rsp->result = __constant_cpu_to_le16(L2CAP_IR_SUCCESS);
4317                 memcpy(rsp->data, l2cap_fixed_chan, sizeof(l2cap_fixed_chan));
4318                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4319                                buf);
4320         } else {
4321                 struct l2cap_info_rsp rsp;
4322                 rsp.type   = cpu_to_le16(type);
4323                 rsp.result = __constant_cpu_to_le16(L2CAP_IR_NOTSUPP);
4324                 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4325                                &rsp);
4326         }
4327
4328         return 0;
4329 }
4330
4331 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4332                                         struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4333                                         u8 *data)
4334 {
4335         struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4336         u16 type, result;
4337
4338         if (cmd_len < sizeof(*rsp))
4339                 return -EPROTO;
4340
4341         type   = __le16_to_cpu(rsp->type);
4342         result = __le16_to_cpu(rsp->result);
4343
4344         BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4345
4346         /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4347         if (cmd->ident != conn->info_ident ||
4348             conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4349                 return 0;
4350
4351         cancel_delayed_work(&conn->info_timer);
4352
4353         if (result != L2CAP_IR_SUCCESS) {
4354                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4355                 conn->info_ident = 0;
4356
4357                 l2cap_conn_start(conn);
4358
4359                 return 0;
4360         }
4361
4362         switch (type) {
4363         case L2CAP_IT_FEAT_MASK:
4364                 conn->feat_mask = get_unaligned_le32(rsp->data);
4365
4366                 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4367                         struct l2cap_info_req req;
4368                         req.type = __constant_cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4369
4370                         conn->info_ident = l2cap_get_ident(conn);
4371
4372                         l2cap_send_cmd(conn, conn->info_ident,
4373                                        L2CAP_INFO_REQ, sizeof(req), &req);
4374                 } else {
4375                         conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4376                         conn->info_ident = 0;
4377
4378                         l2cap_conn_start(conn);
4379                 }
4380                 break;
4381
4382         case L2CAP_IT_FIXED_CHAN:
4383                 conn->fixed_chan_mask = rsp->data[0];
4384                 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4385                 conn->info_ident = 0;
4386
4387                 l2cap_conn_start(conn);
4388                 break;
4389         }
4390
4391         return 0;
4392 }
4393
4394 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4395                                     struct l2cap_cmd_hdr *cmd,
4396                                     u16 cmd_len, void *data)
4397 {
4398         struct l2cap_create_chan_req *req = data;
4399         struct l2cap_create_chan_rsp rsp;
4400         struct l2cap_chan *chan;
4401         struct hci_dev *hdev;
4402         u16 psm, scid;
4403
4404         if (cmd_len != sizeof(*req))
4405                 return -EPROTO;
4406
4407         if (!enable_hs)
4408                 return -EINVAL;
4409
4410         psm = le16_to_cpu(req->psm);
4411         scid = le16_to_cpu(req->scid);
4412
4413         BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4414
4415         /* For controller id 0 make BR/EDR connection */
4416         if (req->amp_id == HCI_BREDR_ID) {
4417                 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4418                               req->amp_id);
4419                 return 0;
4420         }
4421
4422         /* Validate AMP controller id */
4423         hdev = hci_dev_get(req->amp_id);
4424         if (!hdev)
4425                 goto error;
4426
4427         if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4428                 hci_dev_put(hdev);
4429                 goto error;
4430         }
4431
4432         chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4433                              req->amp_id);
4434         if (chan) {
4435                 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4436                 struct hci_conn *hs_hcon;
4437
4438                 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK, conn->dst);
4439                 if (!hs_hcon) {
4440                         hci_dev_put(hdev);
4441                         return -EFAULT;
4442                 }
4443
4444                 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4445
4446                 mgr->bredr_chan = chan;
4447                 chan->hs_hcon = hs_hcon;
4448                 chan->fcs = L2CAP_FCS_NONE;
4449                 conn->mtu = hdev->block_mtu;
4450         }
4451
4452         hci_dev_put(hdev);
4453
4454         return 0;
4455
4456 error:
4457         rsp.dcid = 0;
4458         rsp.scid = cpu_to_le16(scid);
4459         rsp.result = __constant_cpu_to_le16(L2CAP_CR_BAD_AMP);
4460         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4461
4462         l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4463                        sizeof(rsp), &rsp);
4464
4465         return -EFAULT;
4466 }
4467
4468 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4469 {
4470         struct l2cap_move_chan_req req;
4471         u8 ident;
4472
4473         BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4474
4475         ident = l2cap_get_ident(chan->conn);
4476         chan->ident = ident;
4477
4478         req.icid = cpu_to_le16(chan->scid);
4479         req.dest_amp_id = dest_amp_id;
4480
4481         l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4482                        &req);
4483
4484         __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4485 }
4486
4487 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4488 {
4489         struct l2cap_move_chan_rsp rsp;
4490
4491         BT_DBG("chan %p, result 0x%4.4x", chan, result);
4492
4493         rsp.icid = cpu_to_le16(chan->dcid);
4494         rsp.result = cpu_to_le16(result);
4495
4496         l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4497                        sizeof(rsp), &rsp);
4498 }
4499
4500 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4501 {
4502         struct l2cap_move_chan_cfm cfm;
4503
4504         BT_DBG("chan %p, result 0x%4.4x", chan, result);
4505
4506         chan->ident = l2cap_get_ident(chan->conn);
4507
4508         cfm.icid = cpu_to_le16(chan->scid);
4509         cfm.result = cpu_to_le16(result);
4510
4511         l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4512                        sizeof(cfm), &cfm);
4513
4514         __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4515 }
4516
4517 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4518 {
4519         struct l2cap_move_chan_cfm cfm;
4520
4521         BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4522
4523         cfm.icid = cpu_to_le16(icid);
4524         cfm.result = __constant_cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4525
4526         l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4527                        sizeof(cfm), &cfm);
4528 }
4529
4530 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4531                                          u16 icid)
4532 {
4533         struct l2cap_move_chan_cfm_rsp rsp;
4534
4535         BT_DBG("icid 0x%4.4x", icid);
4536
4537         rsp.icid = cpu_to_le16(icid);
4538         l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4539 }
4540
4541 static void __release_logical_link(struct l2cap_chan *chan)
4542 {
4543         chan->hs_hchan = NULL;
4544         chan->hs_hcon = NULL;
4545
4546         /* Placeholder - release the logical link */
4547 }
4548
4549 static void l2cap_logical_fail(struct l2cap_chan *chan)
4550 {
4551         /* Logical link setup failed */
4552         if (chan->state != BT_CONNECTED) {
4553                 /* Create channel failure, disconnect */
4554                 l2cap_send_disconn_req(chan, ECONNRESET);
4555                 return;
4556         }
4557
4558         switch (chan->move_role) {
4559         case L2CAP_MOVE_ROLE_RESPONDER:
4560                 l2cap_move_done(chan);
4561                 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4562                 break;
4563         case L2CAP_MOVE_ROLE_INITIATOR:
4564                 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4565                     chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4566                         /* Remote has only sent pending or
4567                          * success responses, clean up
4568                          */
4569                         l2cap_move_done(chan);
4570                 }
4571
4572                 /* Other amp move states imply that the move
4573                  * has already aborted
4574                  */
4575                 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4576                 break;
4577         }
4578 }
4579
4580 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4581                                         struct hci_chan *hchan)
4582 {
4583         struct l2cap_conf_rsp rsp;
4584
4585         chan->hs_hchan = hchan;
4586         chan->hs_hcon->l2cap_data = chan->conn;
4587
4588         l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4589
4590         if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4591                 int err;
4592
4593                 set_default_fcs(chan);
4594
4595                 err = l2cap_ertm_init(chan);
4596                 if (err < 0)
4597                         l2cap_send_disconn_req(chan, -err);
4598                 else
4599                         l2cap_chan_ready(chan);
4600         }
4601 }
4602
4603 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4604                                       struct hci_chan *hchan)
4605 {
4606         chan->hs_hcon = hchan->conn;
4607         chan->hs_hcon->l2cap_data = chan->conn;
4608
4609         BT_DBG("move_state %d", chan->move_state);
4610
4611         switch (chan->move_state) {
4612         case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4613                 /* Move confirm will be sent after a success
4614                  * response is received
4615                  */
4616                 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4617                 break;
4618         case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4619                 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4620                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4621                 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4622                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4623                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4624                 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4625                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4626                         l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4627                 }
4628                 break;
4629         default:
4630                 /* Move was not in expected state, free the channel */
4631                 __release_logical_link(chan);
4632
4633                 chan->move_state = L2CAP_MOVE_STABLE;
4634         }
4635 }
4636
4637 /* Call with chan locked */
4638 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4639                        u8 status)
4640 {
4641         BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4642
4643         if (status) {
4644                 l2cap_logical_fail(chan);
4645                 __release_logical_link(chan);
4646                 return;
4647         }
4648
4649         if (chan->state != BT_CONNECTED) {
4650                 /* Ignore logical link if channel is on BR/EDR */
4651                 if (chan->local_amp_id)
4652                         l2cap_logical_finish_create(chan, hchan);
4653         } else {
4654                 l2cap_logical_finish_move(chan, hchan);
4655         }
4656 }
4657
4658 void l2cap_move_start(struct l2cap_chan *chan)
4659 {
4660         BT_DBG("chan %p", chan);
4661
4662         if (chan->local_amp_id == HCI_BREDR_ID) {
4663                 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4664                         return;
4665                 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4666                 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4667                 /* Placeholder - start physical link setup */
4668         } else {
4669                 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4670                 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4671                 chan->move_id = 0;
4672                 l2cap_move_setup(chan);
4673                 l2cap_send_move_chan_req(chan, 0);
4674         }
4675 }
4676
4677 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4678                             u8 local_amp_id, u8 remote_amp_id)
4679 {
4680         BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4681                local_amp_id, remote_amp_id);
4682
4683         chan->fcs = L2CAP_FCS_NONE;
4684
4685         /* Outgoing channel on AMP */
4686         if (chan->state == BT_CONNECT) {
4687                 if (result == L2CAP_CR_SUCCESS) {
4688                         chan->local_amp_id = local_amp_id;
4689                         l2cap_send_create_chan_req(chan, remote_amp_id);
4690                 } else {
4691                         /* Revert to BR/EDR connect */
4692                         l2cap_send_conn_req(chan);
4693                 }
4694
4695                 return;
4696         }
4697
4698         /* Incoming channel on AMP */
4699         if (__l2cap_no_conn_pending(chan)) {
4700                 struct l2cap_conn_rsp rsp;
4701                 char buf[128];
4702                 rsp.scid = cpu_to_le16(chan->dcid);
4703                 rsp.dcid = cpu_to_le16(chan->scid);
4704
4705                 if (result == L2CAP_CR_SUCCESS) {
4706                         /* Send successful response */
4707                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_SUCCESS);
4708                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4709                 } else {
4710                         /* Send negative response */
4711                         rsp.result = __constant_cpu_to_le16(L2CAP_CR_NO_MEM);
4712                         rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
4713                 }
4714
4715                 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4716                                sizeof(rsp), &rsp);
4717
4718                 if (result == L2CAP_CR_SUCCESS) {
4719                         __l2cap_state_change(chan, BT_CONFIG);
4720                         set_bit(CONF_REQ_SENT, &chan->conf_state);
4721                         l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4722                                        L2CAP_CONF_REQ,
4723                                        l2cap_build_conf_req(chan, buf), buf);
4724                         chan->num_conf_req++;
4725                 }
4726         }
4727 }
4728
4729 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4730                                    u8 remote_amp_id)
4731 {
4732         l2cap_move_setup(chan);
4733         chan->move_id = local_amp_id;
4734         chan->move_state = L2CAP_MOVE_WAIT_RSP;
4735
4736         l2cap_send_move_chan_req(chan, remote_amp_id);
4737 }
4738
4739 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4740 {
4741         struct hci_chan *hchan = NULL;
4742
4743         /* Placeholder - get hci_chan for logical link */
4744
4745         if (hchan) {
4746                 if (hchan->state == BT_CONNECTED) {
4747                         /* Logical link is ready to go */
4748                         chan->hs_hcon = hchan->conn;
4749                         chan->hs_hcon->l2cap_data = chan->conn;
4750                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4751                         l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4752
4753                         l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4754                 } else {
4755                         /* Wait for logical link to be ready */
4756                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4757                 }
4758         } else {
4759                 /* Logical link not available */
4760                 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4761         }
4762 }
4763
4764 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4765 {
4766         if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4767                 u8 rsp_result;
4768                 if (result == -EINVAL)
4769                         rsp_result = L2CAP_MR_BAD_ID;
4770                 else
4771                         rsp_result = L2CAP_MR_NOT_ALLOWED;
4772
4773                 l2cap_send_move_chan_rsp(chan, rsp_result);
4774         }
4775
4776         chan->move_role = L2CAP_MOVE_ROLE_NONE;
4777         chan->move_state = L2CAP_MOVE_STABLE;
4778
4779         /* Restart data transmission */
4780         l2cap_ertm_send(chan);
4781 }
4782
4783 /* Invoke with locked chan */
4784 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4785 {
4786         u8 local_amp_id = chan->local_amp_id;
4787         u8 remote_amp_id = chan->remote_amp_id;
4788
4789         BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4790                chan, result, local_amp_id, remote_amp_id);
4791
4792         if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4793                 l2cap_chan_unlock(chan);
4794                 return;
4795         }
4796
4797         if (chan->state != BT_CONNECTED) {
4798                 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4799         } else if (result != L2CAP_MR_SUCCESS) {
4800                 l2cap_do_move_cancel(chan, result);
4801         } else {
4802                 switch (chan->move_role) {
4803                 case L2CAP_MOVE_ROLE_INITIATOR:
4804                         l2cap_do_move_initiate(chan, local_amp_id,
4805                                                remote_amp_id);
4806                         break;
4807                 case L2CAP_MOVE_ROLE_RESPONDER:
4808                         l2cap_do_move_respond(chan, result);
4809                         break;
4810                 default:
4811                         l2cap_do_move_cancel(chan, result);
4812                         break;
4813                 }
4814         }
4815 }
4816
4817 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4818                                          struct l2cap_cmd_hdr *cmd,
4819                                          u16 cmd_len, void *data)
4820 {
4821         struct l2cap_move_chan_req *req = data;
4822         struct l2cap_move_chan_rsp rsp;
4823         struct l2cap_chan *chan;
4824         u16 icid = 0;
4825         u16 result = L2CAP_MR_NOT_ALLOWED;
4826
4827         if (cmd_len != sizeof(*req))
4828                 return -EPROTO;
4829
4830         icid = le16_to_cpu(req->icid);
4831
4832         BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4833
4834         if (!enable_hs)
4835                 return -EINVAL;
4836
4837         chan = l2cap_get_chan_by_dcid(conn, icid);
4838         if (!chan) {
4839                 rsp.icid = cpu_to_le16(icid);
4840                 rsp.result = __constant_cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4841                 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4842                                sizeof(rsp), &rsp);
4843                 return 0;
4844         }
4845
4846         chan->ident = cmd->ident;
4847
4848         if (chan->scid < L2CAP_CID_DYN_START ||
4849             chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4850             (chan->mode != L2CAP_MODE_ERTM &&
4851              chan->mode != L2CAP_MODE_STREAMING)) {
4852                 result = L2CAP_MR_NOT_ALLOWED;
4853                 goto send_move_response;
4854         }
4855
4856         if (chan->local_amp_id == req->dest_amp_id) {
4857                 result = L2CAP_MR_SAME_ID;
4858                 goto send_move_response;
4859         }
4860
4861         if (req->dest_amp_id) {
4862                 struct hci_dev *hdev;
4863                 hdev = hci_dev_get(req->dest_amp_id);
4864                 if (!hdev || hdev->dev_type != HCI_AMP ||
4865                     !test_bit(HCI_UP, &hdev->flags)) {
4866                         if (hdev)
4867                                 hci_dev_put(hdev);
4868
4869                         result = L2CAP_MR_BAD_ID;
4870                         goto send_move_response;
4871                 }
4872                 hci_dev_put(hdev);
4873         }
4874
4875         /* Detect a move collision.  Only send a collision response
4876          * if this side has "lost", otherwise proceed with the move.
4877          * The winner has the larger bd_addr.
4878          */
4879         if ((__chan_is_moving(chan) ||
4880              chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4881             bacmp(conn->src, conn->dst) > 0) {
4882                 result = L2CAP_MR_COLLISION;
4883                 goto send_move_response;
4884         }
4885
4886         chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4887         l2cap_move_setup(chan);
4888         chan->move_id = req->dest_amp_id;
4889         icid = chan->dcid;
4890
4891         if (!req->dest_amp_id) {
4892                 /* Moving to BR/EDR */
4893                 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4894                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4895                         result = L2CAP_MR_PEND;
4896                 } else {
4897                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4898                         result = L2CAP_MR_SUCCESS;
4899                 }
4900         } else {
4901                 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4902                 /* Placeholder - uncomment when amp functions are available */
4903                 /*amp_accept_physical(chan, req->dest_amp_id);*/
4904                 result = L2CAP_MR_PEND;
4905         }
4906
4907 send_move_response:
4908         l2cap_send_move_chan_rsp(chan, result);
4909
4910         l2cap_chan_unlock(chan);
4911
4912         return 0;
4913 }
4914
4915 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4916 {
4917         struct l2cap_chan *chan;
4918         struct hci_chan *hchan = NULL;
4919
4920         chan = l2cap_get_chan_by_scid(conn, icid);
4921         if (!chan) {
4922                 l2cap_send_move_chan_cfm_icid(conn, icid);
4923                 return;
4924         }
4925
4926         __clear_chan_timer(chan);
4927         if (result == L2CAP_MR_PEND)
4928                 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4929
4930         switch (chan->move_state) {
4931         case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4932                 /* Move confirm will be sent when logical link
4933                  * is complete.
4934                  */
4935                 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4936                 break;
4937         case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4938                 if (result == L2CAP_MR_PEND) {
4939                         break;
4940                 } else if (test_bit(CONN_LOCAL_BUSY,
4941                                     &chan->conn_state)) {
4942                         chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4943                 } else {
4944                         /* Logical link is up or moving to BR/EDR,
4945                          * proceed with move
4946                          */
4947                         chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4948                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4949                 }
4950                 break;
4951         case L2CAP_MOVE_WAIT_RSP:
4952                 /* Moving to AMP */
4953                 if (result == L2CAP_MR_SUCCESS) {
4954                         /* Remote is ready, send confirm immediately
4955                          * after logical link is ready
4956                          */
4957                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4958                 } else {
4959                         /* Both logical link and move success
4960                          * are required to confirm
4961                          */
4962                         chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
4963                 }
4964
4965                 /* Placeholder - get hci_chan for logical link */
4966                 if (!hchan) {
4967                         /* Logical link not available */
4968                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4969                         break;
4970                 }
4971
4972                 /* If the logical link is not yet connected, do not
4973                  * send confirmation.
4974                  */
4975                 if (hchan->state != BT_CONNECTED)
4976                         break;
4977
4978                 /* Logical link is already ready to go */
4979
4980                 chan->hs_hcon = hchan->conn;
4981                 chan->hs_hcon->l2cap_data = chan->conn;
4982
4983                 if (result == L2CAP_MR_SUCCESS) {
4984                         /* Can confirm now */
4985                         l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4986                 } else {
4987                         /* Now only need move success
4988                          * to confirm
4989                          */
4990                         chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4991                 }
4992
4993                 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4994                 break;
4995         default:
4996                 /* Any other amp move state means the move failed. */
4997                 chan->move_id = chan->local_amp_id;
4998                 l2cap_move_done(chan);
4999                 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5000         }
5001
5002         l2cap_chan_unlock(chan);
5003 }
5004
5005 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5006                             u16 result)
5007 {
5008         struct l2cap_chan *chan;
5009
5010         chan = l2cap_get_chan_by_ident(conn, ident);
5011         if (!chan) {
5012                 /* Could not locate channel, icid is best guess */
5013                 l2cap_send_move_chan_cfm_icid(conn, icid);
5014                 return;
5015         }
5016
5017         __clear_chan_timer(chan);
5018
5019         if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5020                 if (result == L2CAP_MR_COLLISION) {
5021                         chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5022                 } else {
5023                         /* Cleanup - cancel move */
5024                         chan->move_id = chan->local_amp_id;
5025                         l2cap_move_done(chan);
5026                 }
5027         }
5028
5029         l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5030
5031         l2cap_chan_unlock(chan);
5032 }
5033
5034 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5035                                   struct l2cap_cmd_hdr *cmd,
5036                                   u16 cmd_len, void *data)
5037 {
5038         struct l2cap_move_chan_rsp *rsp = data;
5039         u16 icid, result;
5040
5041         if (cmd_len != sizeof(*rsp))
5042                 return -EPROTO;
5043
5044         icid = le16_to_cpu(rsp->icid);
5045         result = le16_to_cpu(rsp->result);
5046
5047         BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5048
5049         if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5050                 l2cap_move_continue(conn, icid, result);
5051         else
5052                 l2cap_move_fail(conn, cmd->ident, icid, result);
5053
5054         return 0;
5055 }
5056
5057 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5058                                       struct l2cap_cmd_hdr *cmd,
5059                                       u16 cmd_len, void *data)
5060 {
5061         struct l2cap_move_chan_cfm *cfm = data;
5062         struct l2cap_chan *chan;
5063         u16 icid, result;
5064
5065         if (cmd_len != sizeof(*cfm))
5066                 return -EPROTO;
5067
5068         icid = le16_to_cpu(cfm->icid);
5069         result = le16_to_cpu(cfm->result);
5070
5071         BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5072
5073         chan = l2cap_get_chan_by_dcid(conn, icid);
5074         if (!chan) {
5075                 /* Spec requires a response even if the icid was not found */
5076                 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5077                 return 0;
5078         }
5079
5080         if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5081                 if (result == L2CAP_MC_CONFIRMED) {
5082                         chan->local_amp_id = chan->move_id;
5083                         if (!chan->local_amp_id)
5084                                 __release_logical_link(chan);
5085                 } else {
5086                         chan->move_id = chan->local_amp_id;
5087                 }
5088
5089                 l2cap_move_done(chan);
5090         }
5091
5092         l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5093
5094         l2cap_chan_unlock(chan);
5095
5096         return 0;
5097 }
5098
5099 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5100                                                  struct l2cap_cmd_hdr *cmd,
5101                                                  u16 cmd_len, void *data)
5102 {
5103         struct l2cap_move_chan_cfm_rsp *rsp = data;
5104         struct l2cap_chan *chan;
5105         u16 icid;
5106
5107         if (cmd_len != sizeof(*rsp))
5108                 return -EPROTO;
5109
5110         icid = le16_to_cpu(rsp->icid);
5111
5112         BT_DBG("icid 0x%4.4x", icid);
5113
5114         chan = l2cap_get_chan_by_scid(conn, icid);
5115         if (!chan)
5116                 return 0;
5117
5118         __clear_chan_timer(chan);
5119
5120         if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5121                 chan->local_amp_id = chan->move_id;
5122
5123                 if (!chan->local_amp_id && chan->hs_hchan)
5124                         __release_logical_link(chan);
5125
5126                 l2cap_move_done(chan);
5127         }
5128
5129         l2cap_chan_unlock(chan);
5130
5131         return 0;
5132 }
5133
5134 static inline int l2cap_check_conn_param(u16 min, u16 max, u16 latency,
5135                                          u16 to_multiplier)
5136 {
5137         u16 max_latency;
5138
5139         if (min > max || min < 6 || max > 3200)
5140                 return -EINVAL;
5141
5142         if (to_multiplier < 10 || to_multiplier > 3200)
5143                 return -EINVAL;
5144
5145         if (max >= to_multiplier * 8)
5146                 return -EINVAL;
5147
5148         max_latency = (to_multiplier * 8 / max) - 1;
5149         if (latency > 499 || latency > max_latency)
5150                 return -EINVAL;
5151
5152         return 0;
5153 }
5154
5155 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5156                                               struct l2cap_cmd_hdr *cmd,
5157                                               u8 *data)
5158 {
5159         struct hci_conn *hcon = conn->hcon;
5160         struct l2cap_conn_param_update_req *req;
5161         struct l2cap_conn_param_update_rsp rsp;
5162         u16 min, max, latency, to_multiplier, cmd_len;
5163         int err;
5164
5165         if (!(hcon->link_mode & HCI_LM_MASTER))
5166                 return -EINVAL;
5167
5168         cmd_len = __le16_to_cpu(cmd->len);
5169         if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5170                 return -EPROTO;
5171
5172         req = (struct l2cap_conn_param_update_req *) data;
5173         min             = __le16_to_cpu(req->min);
5174         max             = __le16_to_cpu(req->max);
5175         latency         = __le16_to_cpu(req->latency);
5176         to_multiplier   = __le16_to_cpu(req->to_multiplier);
5177
5178         BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5179                min, max, latency, to_multiplier);
5180
5181         memset(&rsp, 0, sizeof(rsp));
5182
5183         err = l2cap_check_conn_param(min, max, latency, to_multiplier);
5184         if (err)
5185                 rsp.result = __constant_cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5186         else
5187                 rsp.result = __constant_cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5188
5189         l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5190                        sizeof(rsp), &rsp);
5191
5192         if (!err)
5193                 hci_le_conn_update(hcon, min, max, latency, to_multiplier);
5194
5195         return 0;
5196 }
5197
5198 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5199                                       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5200                                       u8 *data)
5201 {
5202         int err = 0;
5203
5204         switch (cmd->code) {
5205         case L2CAP_COMMAND_REJ:
5206                 l2cap_command_rej(conn, cmd, cmd_len, data);
5207                 break;
5208
5209         case L2CAP_CONN_REQ:
5210                 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5211                 break;
5212
5213         case L2CAP_CONN_RSP:
5214         case L2CAP_CREATE_CHAN_RSP:
5215                 err = l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5216                 break;
5217
5218         case L2CAP_CONF_REQ:
5219                 err = l2cap_config_req(conn, cmd, cmd_len, data);
5220                 break;
5221
5222         case L2CAP_CONF_RSP:
5223                 err = l2cap_config_rsp(conn, cmd, cmd_len, data);
5224                 break;
5225
5226         case L2CAP_DISCONN_REQ:
5227                 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5228                 break;
5229
5230         case L2CAP_DISCONN_RSP:
5231                 err = l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5232                 break;
5233
5234         case L2CAP_ECHO_REQ:
5235                 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5236                 break;
5237
5238         case L2CAP_ECHO_RSP:
5239                 break;
5240
5241         case L2CAP_INFO_REQ:
5242                 err = l2cap_information_req(conn, cmd, cmd_len, data);
5243                 break;
5244
5245         case L2CAP_INFO_RSP:
5246                 err = l2cap_information_rsp(conn, cmd, cmd_len, data);
5247                 break;
5248
5249         case L2CAP_CREATE_CHAN_REQ:
5250                 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5251                 break;
5252
5253         case L2CAP_MOVE_CHAN_REQ:
5254                 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5255                 break;
5256
5257         case L2CAP_MOVE_CHAN_RSP:
5258                 err = l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5259                 break;
5260
5261         case L2CAP_MOVE_CHAN_CFM:
5262                 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5263                 break;
5264
5265         case L2CAP_MOVE_CHAN_CFM_RSP:
5266                 err = l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5267                 break;
5268
5269         default:
5270                 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5271                 err = -EINVAL;
5272                 break;
5273         }
5274
5275         return err;
5276 }
5277
5278 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5279                                    struct l2cap_cmd_hdr *cmd, u8 *data)
5280 {
5281         switch (cmd->code) {
5282         case L2CAP_COMMAND_REJ:
5283                 return 0;
5284
5285         case L2CAP_CONN_PARAM_UPDATE_REQ:
5286                 return l2cap_conn_param_update_req(conn, cmd, data);
5287
5288         case L2CAP_CONN_PARAM_UPDATE_RSP:
5289                 return 0;
5290
5291         default:
5292                 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5293                 return -EINVAL;
5294         }
5295 }
5296
5297 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5298                                         struct sk_buff *skb)
5299 {
5300         u8 *data = skb->data;
5301         int len = skb->len;
5302         struct l2cap_cmd_hdr cmd;
5303         int err;
5304
5305         l2cap_raw_recv(conn, skb);
5306
5307         while (len >= L2CAP_CMD_HDR_SIZE) {
5308                 u16 cmd_len;
5309                 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5310                 data += L2CAP_CMD_HDR_SIZE;
5311                 len  -= L2CAP_CMD_HDR_SIZE;
5312
5313                 cmd_len = le16_to_cpu(cmd.len);
5314
5315                 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5316                        cmd.ident);
5317
5318                 if (cmd_len > len || !cmd.ident) {
5319                         BT_DBG("corrupted command");
5320                         break;
5321                 }
5322
5323                 err = l2cap_le_sig_cmd(conn, &cmd, data);
5324                 if (err) {
5325                         struct l2cap_cmd_rej_unk rej;
5326
5327                         BT_ERR("Wrong link type (%d)", err);
5328
5329                         /* FIXME: Map err to a valid reason */
5330                         rej.reason = __constant_cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5331                         l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5332                                        sizeof(rej), &rej);
5333                 }
5334
5335                 data += cmd_len;
5336                 len  -= cmd_len;
5337         }
5338
5339         kfree_skb(skb);
5340 }
5341
5342 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5343                                      struct sk_buff *skb)
5344 {
5345         u8 *data = skb->data;
5346         int len = skb->len;
5347         struct l2cap_cmd_hdr cmd;
5348         int err;
5349
5350         l2cap_raw_recv(conn, skb);
5351
5352         while (len >= L2CAP_CMD_HDR_SIZE) {
5353                 u16 cmd_len;
5354                 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5355                 data += L2CAP_CMD_HDR_SIZE;
5356                 len  -= L2CAP_CMD_HDR_SIZE;
5357
5358                 cmd_len = le16_to_cpu(cmd.len);
5359
5360                 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5361                        cmd.ident);
5362
5363                 if (cmd_len > len || !cmd.ident) {
5364                         BT_DBG("corrupted command");
5365                         break;
5366                 }
5367
5368                 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5369                 if (err) {
5370                         struct l2cap_cmd_rej_unk rej;
5371
5372                         BT_ERR("Wrong link type (%d)", err);
5373
5374                         /* FIXME: Map err to a valid reason */
5375                         rej.reason = __constant_cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5376                         l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5377                                        sizeof(rej), &rej);
5378                 }
5379
5380                 data += cmd_len;
5381                 len  -= cmd_len;
5382         }
5383
5384         kfree_skb(skb);
5385 }
5386
5387 static int l2cap_check_fcs(struct l2cap_chan *chan,  struct sk_buff *skb)
5388 {
5389         u16 our_fcs, rcv_fcs;
5390         int hdr_size;
5391
5392         if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5393                 hdr_size = L2CAP_EXT_HDR_SIZE;
5394         else
5395                 hdr_size = L2CAP_ENH_HDR_SIZE;
5396
5397         if (chan->fcs == L2CAP_FCS_CRC16) {
5398                 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5399                 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5400                 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5401
5402                 if (our_fcs != rcv_fcs)
5403                         return -EBADMSG;
5404         }
5405         return 0;
5406 }
5407
5408 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5409 {
5410         struct l2cap_ctrl control;
5411
5412         BT_DBG("chan %p", chan);
5413
5414         memset(&control, 0, sizeof(control));
5415         control.sframe = 1;
5416         control.final = 1;
5417         control.reqseq = chan->buffer_seq;
5418         set_bit(CONN_SEND_FBIT, &chan->conn_state);
5419
5420         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5421                 control.super = L2CAP_SUPER_RNR;
5422                 l2cap_send_sframe(chan, &control);
5423         }
5424
5425         if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5426             chan->unacked_frames > 0)
5427                 __set_retrans_timer(chan);
5428
5429         /* Send pending iframes */
5430         l2cap_ertm_send(chan);
5431
5432         if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5433             test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5434                 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5435                  * send it now.
5436                  */
5437                 control.super = L2CAP_SUPER_RR;
5438                 l2cap_send_sframe(chan, &control);
5439         }
5440 }
5441
5442 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5443                             struct sk_buff **last_frag)
5444 {
5445         /* skb->len reflects data in skb as well as all fragments
5446          * skb->data_len reflects only data in fragments
5447          */
5448         if (!skb_has_frag_list(skb))
5449                 skb_shinfo(skb)->frag_list = new_frag;
5450
5451         new_frag->next = NULL;
5452
5453         (*last_frag)->next = new_frag;
5454         *last_frag = new_frag;
5455
5456         skb->len += new_frag->len;
5457         skb->data_len += new_frag->len;
5458         skb->truesize += new_frag->truesize;
5459 }
5460
5461 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5462                                 struct l2cap_ctrl *control)
5463 {
5464         int err = -EINVAL;
5465
5466         switch (control->sar) {
5467         case L2CAP_SAR_UNSEGMENTED:
5468                 if (chan->sdu)
5469                         break;
5470
5471                 err = chan->ops->recv(chan, skb);
5472                 break;
5473
5474         case L2CAP_SAR_START:
5475                 if (chan->sdu)
5476                         break;
5477
5478                 chan->sdu_len = get_unaligned_le16(skb->data);
5479                 skb_pull(skb, L2CAP_SDULEN_SIZE);
5480
5481                 if (chan->sdu_len > chan->imtu) {
5482                         err = -EMSGSIZE;
5483                         break;
5484                 }
5485
5486                 if (skb->len >= chan->sdu_len)
5487                         break;
5488
5489                 chan->sdu = skb;
5490                 chan->sdu_last_frag = skb;
5491
5492                 skb = NULL;
5493                 err = 0;
5494                 break;
5495
5496         case L2CAP_SAR_CONTINUE:
5497                 if (!chan->sdu)
5498                         break;
5499
5500                 append_skb_frag(chan->sdu, skb,
5501                                 &chan->sdu_last_frag);
5502                 skb = NULL;
5503
5504                 if (chan->sdu->len >= chan->sdu_len)
5505                         break;
5506
5507                 err = 0;
5508                 break;
5509
5510         case L2CAP_SAR_END:
5511                 if (!chan->sdu)
5512                         break;
5513
5514                 append_skb_frag(chan->sdu, skb,
5515                                 &chan->sdu_last_frag);
5516                 skb = NULL;
5517
5518                 if (chan->sdu->len != chan->sdu_len)
5519                         break;
5520
5521                 err = chan->ops->recv(chan, chan->sdu);
5522
5523                 if (!err) {
5524                         /* Reassembly complete */
5525                         chan->sdu = NULL;
5526                         chan->sdu_last_frag = NULL;
5527                         chan->sdu_len = 0;
5528                 }
5529                 break;
5530         }
5531
5532         if (err) {
5533                 kfree_skb(skb);
5534                 kfree_skb(chan->sdu);
5535                 chan->sdu = NULL;
5536                 chan->sdu_last_frag = NULL;
5537                 chan->sdu_len = 0;
5538         }
5539
5540         return err;
5541 }
5542
5543 static int l2cap_resegment(struct l2cap_chan *chan)
5544 {
5545         /* Placeholder */
5546         return 0;
5547 }
5548
5549 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5550 {
5551         u8 event;
5552
5553         if (chan->mode != L2CAP_MODE_ERTM)
5554                 return;
5555
5556         event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5557         l2cap_tx(chan, NULL, NULL, event);
5558 }
5559
5560 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5561 {
5562         int err = 0;
5563         /* Pass sequential frames to l2cap_reassemble_sdu()
5564          * until a gap is encountered.
5565          */
5566
5567         BT_DBG("chan %p", chan);
5568
5569         while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5570                 struct sk_buff *skb;
5571                 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5572                        chan->buffer_seq, skb_queue_len(&chan->srej_q));
5573
5574                 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5575
5576                 if (!skb)
5577                         break;
5578
5579                 skb_unlink(skb, &chan->srej_q);
5580                 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5581                 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->control);
5582                 if (err)
5583                         break;
5584         }
5585
5586         if (skb_queue_empty(&chan->srej_q)) {
5587                 chan->rx_state = L2CAP_RX_STATE_RECV;
5588                 l2cap_send_ack(chan);
5589         }
5590
5591         return err;
5592 }
5593
5594 static void l2cap_handle_srej(struct l2cap_chan *chan,
5595                               struct l2cap_ctrl *control)
5596 {
5597         struct sk_buff *skb;
5598
5599         BT_DBG("chan %p, control %p", chan, control);
5600
5601         if (control->reqseq == chan->next_tx_seq) {
5602                 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5603                 l2cap_send_disconn_req(chan, ECONNRESET);
5604                 return;
5605         }
5606
5607         skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5608
5609         if (skb == NULL) {
5610                 BT_DBG("Seq %d not available for retransmission",
5611                        control->reqseq);
5612                 return;
5613         }
5614
5615         if (chan->max_tx != 0 && bt_cb(skb)->control.retries >= chan->max_tx) {
5616                 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5617                 l2cap_send_disconn_req(chan, ECONNRESET);
5618                 return;
5619         }
5620
5621         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5622
5623         if (control->poll) {
5624                 l2cap_pass_to_tx(chan, control);
5625
5626                 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5627                 l2cap_retransmit(chan, control);
5628                 l2cap_ertm_send(chan);
5629
5630                 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5631                         set_bit(CONN_SREJ_ACT, &chan->conn_state);
5632                         chan->srej_save_reqseq = control->reqseq;
5633                 }
5634         } else {
5635                 l2cap_pass_to_tx_fbit(chan, control);
5636
5637                 if (control->final) {
5638                         if (chan->srej_save_reqseq != control->reqseq ||
5639                             !test_and_clear_bit(CONN_SREJ_ACT,
5640                                                 &chan->conn_state))
5641                                 l2cap_retransmit(chan, control);
5642                 } else {
5643                         l2cap_retransmit(chan, control);
5644                         if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5645                                 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5646                                 chan->srej_save_reqseq = control->reqseq;
5647                         }
5648                 }
5649         }
5650 }
5651
5652 static void l2cap_handle_rej(struct l2cap_chan *chan,
5653                              struct l2cap_ctrl *control)
5654 {
5655         struct sk_buff *skb;
5656
5657         BT_DBG("chan %p, control %p", chan, control);
5658
5659         if (control->reqseq == chan->next_tx_seq) {
5660                 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5661                 l2cap_send_disconn_req(chan, ECONNRESET);
5662                 return;
5663         }
5664
5665         skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5666
5667         if (chan->max_tx && skb &&
5668             bt_cb(skb)->control.retries >= chan->max_tx) {
5669                 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5670                 l2cap_send_disconn_req(chan, ECONNRESET);
5671                 return;
5672         }
5673
5674         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5675
5676         l2cap_pass_to_tx(chan, control);
5677
5678         if (control->final) {
5679                 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
5680                         l2cap_retransmit_all(chan, control);
5681         } else {
5682                 l2cap_retransmit_all(chan, control);
5683                 l2cap_ertm_send(chan);
5684                 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
5685                         set_bit(CONN_REJ_ACT, &chan->conn_state);
5686         }
5687 }
5688
5689 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
5690 {
5691         BT_DBG("chan %p, txseq %d", chan, txseq);
5692
5693         BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
5694                chan->expected_tx_seq);
5695
5696         if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
5697                 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
5698                     chan->tx_win) {
5699                         /* See notes below regarding "double poll" and
5700                          * invalid packets.
5701                          */
5702                         if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
5703                                 BT_DBG("Invalid/Ignore - after SREJ");
5704                                 return L2CAP_TXSEQ_INVALID_IGNORE;
5705                         } else {
5706                                 BT_DBG("Invalid - in window after SREJ sent");
5707                                 return L2CAP_TXSEQ_INVALID;
5708                         }
5709                 }
5710
5711                 if (chan->srej_list.head == txseq) {
5712                         BT_DBG("Expected SREJ");
5713                         return L2CAP_TXSEQ_EXPECTED_SREJ;
5714                 }
5715
5716                 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
5717                         BT_DBG("Duplicate SREJ - txseq already stored");
5718                         return L2CAP_TXSEQ_DUPLICATE_SREJ;
5719                 }
5720
5721                 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
5722                         BT_DBG("Unexpected SREJ - not requested");
5723                         return L2CAP_TXSEQ_UNEXPECTED_SREJ;
5724                 }
5725         }
5726
5727         if (chan->expected_tx_seq == txseq) {
5728                 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
5729                     chan->tx_win) {
5730                         BT_DBG("Invalid - txseq outside tx window");
5731                         return L2CAP_TXSEQ_INVALID;
5732                 } else {
5733                         BT_DBG("Expected");
5734                         return L2CAP_TXSEQ_EXPECTED;
5735                 }
5736         }
5737
5738         if (__seq_offset(chan, txseq, chan->last_acked_seq) <
5739             __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
5740                 BT_DBG("Duplicate - expected_tx_seq later than txseq");
5741                 return L2CAP_TXSEQ_DUPLICATE;
5742         }
5743
5744         if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
5745                 /* A source of invalid packets is a "double poll" condition,
5746                  * where delays cause us to send multiple poll packets.  If
5747                  * the remote stack receives and processes both polls,
5748                  * sequence numbers can wrap around in such a way that a
5749                  * resent frame has a sequence number that looks like new data
5750                  * with a sequence gap.  This would trigger an erroneous SREJ
5751                  * request.
5752                  *
5753                  * Fortunately, this is impossible with a tx window that's
5754                  * less than half of the maximum sequence number, which allows
5755                  * invalid frames to be safely ignored.
5756                  *
5757                  * With tx window sizes greater than half of the tx window
5758                  * maximum, the frame is invalid and cannot be ignored.  This
5759                  * causes a disconnect.
5760                  */
5761
5762                 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
5763                         BT_DBG("Invalid/Ignore - txseq outside tx window");
5764                         return L2CAP_TXSEQ_INVALID_IGNORE;
5765                 } else {
5766                         BT_DBG("Invalid - txseq outside tx window");
5767                         return L2CAP_TXSEQ_INVALID;
5768                 }
5769         } else {
5770                 BT_DBG("Unexpected - txseq indicates missing frames");
5771                 return L2CAP_TXSEQ_UNEXPECTED;
5772         }
5773 }
5774
5775 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
5776                                struct l2cap_ctrl *control,
5777                                struct sk_buff *skb, u8 event)
5778 {
5779         int err = 0;
5780         bool skb_in_use = 0;
5781
5782         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
5783                event);
5784
5785         switch (event) {
5786         case L2CAP_EV_RECV_IFRAME:
5787                 switch (l2cap_classify_txseq(chan, control->txseq)) {
5788                 case L2CAP_TXSEQ_EXPECTED:
5789                         l2cap_pass_to_tx(chan, control);
5790
5791                         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5792                                 BT_DBG("Busy, discarding expected seq %d",
5793                                        control->txseq);
5794                                 break;
5795                         }
5796
5797                         chan->expected_tx_seq = __next_seq(chan,
5798                                                            control->txseq);
5799
5800                         chan->buffer_seq = chan->expected_tx_seq;
5801                         skb_in_use = 1;
5802
5803                         err = l2cap_reassemble_sdu(chan, skb, control);
5804                         if (err)
5805                                 break;
5806
5807                         if (control->final) {
5808                                 if (!test_and_clear_bit(CONN_REJ_ACT,
5809                                                         &chan->conn_state)) {
5810                                         control->final = 0;
5811                                         l2cap_retransmit_all(chan, control);
5812                                         l2cap_ertm_send(chan);
5813                                 }
5814                         }
5815
5816                         if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
5817                                 l2cap_send_ack(chan);
5818                         break;
5819                 case L2CAP_TXSEQ_UNEXPECTED:
5820                         l2cap_pass_to_tx(chan, control);
5821
5822                         /* Can't issue SREJ frames in the local busy state.
5823                          * Drop this frame, it will be seen as missing
5824                          * when local busy is exited.
5825                          */
5826                         if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5827                                 BT_DBG("Busy, discarding unexpected seq %d",
5828                                        control->txseq);
5829                                 break;
5830                         }
5831
5832                         /* There was a gap in the sequence, so an SREJ
5833                          * must be sent for each missing frame.  The
5834                          * current frame is stored for later use.
5835                          */
5836                         skb_queue_tail(&chan->srej_q, skb);
5837                         skb_in_use = 1;
5838                         BT_DBG("Queued %p (queue len %d)", skb,
5839                                skb_queue_len(&chan->srej_q));
5840
5841                         clear_bit(CONN_SREJ_ACT, &chan->conn_state);
5842                         l2cap_seq_list_clear(&chan->srej_list);
5843                         l2cap_send_srej(chan, control->txseq);
5844
5845                         chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
5846                         break;
5847                 case L2CAP_TXSEQ_DUPLICATE:
5848                         l2cap_pass_to_tx(chan, control);
5849                         break;
5850                 case L2CAP_TXSEQ_INVALID_IGNORE:
5851                         break;
5852                 case L2CAP_TXSEQ_INVALID:
5853                 default:
5854                         l2cap_send_disconn_req(chan, ECONNRESET);
5855                         break;
5856                 }
5857                 break;
5858         case L2CAP_EV_RECV_RR:
5859                 l2cap_pass_to_tx(chan, control);
5860                 if (control->final) {
5861                         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5862
5863                         if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
5864                             !__chan_is_moving(chan)) {
5865                                 control->final = 0;
5866                                 l2cap_retransmit_all(chan, control);
5867                         }
5868
5869                         l2cap_ertm_send(chan);
5870                 } else if (control->poll) {
5871                         l2cap_send_i_or_rr_or_rnr(chan);
5872                 } else {
5873                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
5874                                                &chan->conn_state) &&
5875                             chan->unacked_frames)
5876                                 __set_retrans_timer(chan);
5877
5878                         l2cap_ertm_send(chan);
5879                 }
5880                 break;
5881         case L2CAP_EV_RECV_RNR:
5882                 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5883                 l2cap_pass_to_tx(chan, control);
5884                 if (control && control->poll) {
5885                         set_bit(CONN_SEND_FBIT, &chan->conn_state);
5886                         l2cap_send_rr_or_rnr(chan, 0);
5887                 }
5888                 __clear_retrans_timer(chan);
5889                 l2cap_seq_list_clear(&chan->retrans_list);
5890                 break;
5891         case L2CAP_EV_RECV_REJ:
5892                 l2cap_handle_rej(chan, control);
5893                 break;
5894         case L2CAP_EV_RECV_SREJ:
5895                 l2cap_handle_srej(chan, control);
5896                 break;
5897         default:
5898                 break;
5899         }
5900
5901         if (skb && !skb_in_use) {
5902                 BT_DBG("Freeing %p", skb);
5903                 kfree_skb(skb);
5904         }
5905
5906         return err;
5907 }
5908
5909 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
5910                                     struct l2cap_ctrl *control,
5911                                     struct sk_buff *skb, u8 event)
5912 {
5913         int err = 0;
5914         u16 txseq = control->txseq;
5915         bool skb_in_use = 0;
5916
5917         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
5918                event);
5919
5920         switch (event) {
5921         case L2CAP_EV_RECV_IFRAME:
5922                 switch (l2cap_classify_txseq(chan, txseq)) {
5923                 case L2CAP_TXSEQ_EXPECTED:
5924                         /* Keep frame for reassembly later */
5925                         l2cap_pass_to_tx(chan, control);
5926                         skb_queue_tail(&chan->srej_q, skb);
5927                         skb_in_use = 1;
5928                         BT_DBG("Queued %p (queue len %d)", skb,
5929                                skb_queue_len(&chan->srej_q));
5930
5931                         chan->expected_tx_seq = __next_seq(chan, txseq);
5932                         break;
5933                 case L2CAP_TXSEQ_EXPECTED_SREJ:
5934                         l2cap_seq_list_pop(&chan->srej_list);
5935
5936                         l2cap_pass_to_tx(chan, control);
5937                         skb_queue_tail(&chan->srej_q, skb);
5938                         skb_in_use = 1;
5939                         BT_DBG("Queued %p (queue len %d)", skb,
5940                                skb_queue_len(&chan->srej_q));
5941
5942                         err = l2cap_rx_queued_iframes(chan);
5943                         if (err)
5944                                 break;
5945
5946                         break;
5947                 case L2CAP_TXSEQ_UNEXPECTED:
5948                         /* Got a frame that can't be reassembled yet.
5949                          * Save it for later, and send SREJs to cover
5950                          * the missing frames.
5951                          */
5952                         skb_queue_tail(&chan->srej_q, skb);
5953                         skb_in_use = 1;
5954                         BT_DBG("Queued %p (queue len %d)", skb,
5955                                skb_queue_len(&chan->srej_q));
5956
5957                         l2cap_pass_to_tx(chan, control);
5958                         l2cap_send_srej(chan, control->txseq);
5959                         break;
5960                 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
5961                         /* This frame was requested with an SREJ, but
5962                          * some expected retransmitted frames are
5963                          * missing.  Request retransmission of missing
5964                          * SREJ'd frames.
5965                          */
5966                         skb_queue_tail(&chan->srej_q, skb);
5967                         skb_in_use = 1;
5968                         BT_DBG("Queued %p (queue len %d)", skb,
5969                                skb_queue_len(&chan->srej_q));
5970
5971                         l2cap_pass_to_tx(chan, control);
5972                         l2cap_send_srej_list(chan, control->txseq);
5973                         break;
5974                 case L2CAP_TXSEQ_DUPLICATE_SREJ:
5975                         /* We've already queued this frame.  Drop this copy. */
5976                         l2cap_pass_to_tx(chan, control);
5977                         break;
5978                 case L2CAP_TXSEQ_DUPLICATE:
5979                         /* Expecting a later sequence number, so this frame
5980                          * was already received.  Ignore it completely.
5981                          */
5982                         break;
5983                 case L2CAP_TXSEQ_INVALID_IGNORE:
5984                         break;
5985                 case L2CAP_TXSEQ_INVALID:
5986                 default:
5987                         l2cap_send_disconn_req(chan, ECONNRESET);
5988                         break;
5989                 }
5990                 break;
5991         case L2CAP_EV_RECV_RR:
5992                 l2cap_pass_to_tx(chan, control);
5993                 if (control->final) {
5994                         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5995
5996                         if (!test_and_clear_bit(CONN_REJ_ACT,
5997                                                 &chan->conn_state)) {
5998                                 control->final = 0;
5999                                 l2cap_retransmit_all(chan, control);
6000                         }
6001
6002                         l2cap_ertm_send(chan);
6003                 } else if (control->poll) {
6004                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
6005                                                &chan->conn_state) &&
6006                             chan->unacked_frames) {
6007                                 __set_retrans_timer(chan);
6008                         }
6009
6010                         set_bit(CONN_SEND_FBIT, &chan->conn_state);
6011                         l2cap_send_srej_tail(chan);
6012                 } else {
6013                         if (test_and_clear_bit(CONN_REMOTE_BUSY,
6014                                                &chan->conn_state) &&
6015                             chan->unacked_frames)
6016                                 __set_retrans_timer(chan);
6017
6018                         l2cap_send_ack(chan);
6019                 }
6020                 break;
6021         case L2CAP_EV_RECV_RNR:
6022                 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6023                 l2cap_pass_to_tx(chan, control);
6024                 if (control->poll) {
6025                         l2cap_send_srej_tail(chan);
6026                 } else {
6027                         struct l2cap_ctrl rr_control;
6028                         memset(&rr_control, 0, sizeof(rr_control));
6029                         rr_control.sframe = 1;
6030                         rr_control.super = L2CAP_SUPER_RR;
6031                         rr_control.reqseq = chan->buffer_seq;
6032                         l2cap_send_sframe(chan, &rr_control);
6033                 }
6034
6035                 break;
6036         case L2CAP_EV_RECV_REJ:
6037                 l2cap_handle_rej(chan, control);
6038                 break;
6039         case L2CAP_EV_RECV_SREJ:
6040                 l2cap_handle_srej(chan, control);
6041                 break;
6042         }
6043
6044         if (skb && !skb_in_use) {
6045                 BT_DBG("Freeing %p", skb);
6046                 kfree_skb(skb);
6047         }
6048
6049         return err;
6050 }
6051
6052 static int l2cap_finish_move(struct l2cap_chan *chan)
6053 {
6054         BT_DBG("chan %p", chan);
6055
6056         chan->rx_state = L2CAP_RX_STATE_RECV;
6057
6058         if (chan->hs_hcon)
6059                 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6060         else
6061                 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6062
6063         return l2cap_resegment(chan);
6064 }
6065
6066 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6067                                  struct l2cap_ctrl *control,
6068                                  struct sk_buff *skb, u8 event)
6069 {
6070         int err;
6071
6072         BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6073                event);
6074
6075         if (!control->poll)
6076                 return -EPROTO;
6077
6078         l2cap_process_reqseq(chan, control->reqseq);
6079
6080         if (!skb_queue_empty(&chan->tx_q))
6081                 chan->tx_send_head = skb_peek(&chan->tx_q);
6082         else
6083                 chan->tx_send_head = NULL;
6084
6085         /* Rewind next_tx_seq to the point expected
6086          * by the receiver.
6087          */
6088         chan->next_tx_seq = control->reqseq;
6089         chan->unacked_frames = 0;
6090
6091         err = l2cap_finish_move(chan);
6092         if (err)
6093                 return err;
6094
6095         set_bit(CONN_SEND_FBIT, &chan->conn_state);
6096         l2cap_send_i_or_rr_or_rnr(chan);
6097
6098         if (event == L2CAP_EV_RECV_IFRAME)
6099                 return -EPROTO;
6100
6101         return l2cap_rx_state_recv(chan, control, NULL, event);
6102 }
6103
6104 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6105                                  struct l2cap_ctrl *control,
6106                                  struct sk_buff *skb, u8 event)
6107 {
6108         int err;
6109
6110         if (!control->final)
6111                 return -EPROTO;
6112
6113         clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6114
6115         chan->rx_state = L2CAP_RX_STATE_RECV;
6116         l2cap_process_reqseq(chan, control->reqseq);
6117
6118         if (!skb_queue_empty(&chan->tx_q))
6119                 chan->tx_send_head = skb_peek(&chan->tx_q);
6120         else
6121                 chan->tx_send_head = NULL;
6122
6123         /* Rewind next_tx_seq to the point expected
6124          * by the receiver.
6125          */
6126         chan->next_tx_seq = control->reqseq;
6127         chan->unacked_frames = 0;
6128
6129         if (chan->hs_hcon)
6130                 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6131         else
6132                 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6133
6134         err = l2cap_resegment(chan);
6135
6136         if (!err)
6137                 err = l2cap_rx_state_recv(chan, control, skb, event);
6138
6139         return err;
6140 }
6141
6142 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6143 {
6144         /* Make sure reqseq is for a packet that has been sent but not acked */
6145         u16 unacked;
6146
6147         unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6148         return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6149 }
6150
6151 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6152                     struct sk_buff *skb, u8 event)
6153 {
6154         int err = 0;
6155
6156         BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6157                control, skb, event, chan->rx_state);
6158
6159         if (__valid_reqseq(chan, control->reqseq)) {
6160                 switch (chan->rx_state) {
6161                 case L2CAP_RX_STATE_RECV:
6162                         err = l2cap_rx_state_recv(chan, control, skb, event);
6163                         break;
6164                 case L2CAP_RX_STATE_SREJ_SENT:
6165                         err = l2cap_rx_state_srej_sent(chan, control, skb,
6166                                                        event);
6167                         break;
6168                 case L2CAP_RX_STATE_WAIT_P:
6169                         err = l2cap_rx_state_wait_p(chan, control, skb, event);
6170                         break;
6171                 case L2CAP_RX_STATE_WAIT_F:
6172                         err = l2cap_rx_state_wait_f(chan, control, skb, event);
6173                         break;
6174                 default:
6175                         /* shut it down */
6176                         break;
6177                 }
6178         } else {
6179                 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6180                        control->reqseq, chan->next_tx_seq,
6181                        chan->expected_ack_seq);
6182                 l2cap_send_disconn_req(chan, ECONNRESET);
6183         }
6184
6185         return err;
6186 }
6187
6188 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6189                            struct sk_buff *skb)
6190 {
6191         int err = 0;
6192
6193         BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6194                chan->rx_state);
6195
6196         if (l2cap_classify_txseq(chan, control->txseq) ==
6197             L2CAP_TXSEQ_EXPECTED) {
6198                 l2cap_pass_to_tx(chan, control);
6199
6200                 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6201                        __next_seq(chan, chan->buffer_seq));
6202
6203                 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6204
6205                 l2cap_reassemble_sdu(chan, skb, control);
6206         } else {
6207                 if (chan->sdu) {
6208                         kfree_skb(chan->sdu);
6209                         chan->sdu = NULL;
6210                 }
6211                 chan->sdu_last_frag = NULL;
6212                 chan->sdu_len = 0;
6213
6214                 if (skb) {
6215                         BT_DBG("Freeing %p", skb);
6216                         kfree_skb(skb);
6217                 }
6218         }
6219
6220         chan->last_acked_seq = control->txseq;
6221         chan->expected_tx_seq = __next_seq(chan, control->txseq);
6222
6223         return err;
6224 }
6225
6226 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6227 {
6228         struct l2cap_ctrl *control = &bt_cb(skb)->control;
6229         u16 len;
6230         u8 event;
6231
6232         __unpack_control(chan, skb);
6233
6234         len = skb->len;
6235
6236         /*
6237          * We can just drop the corrupted I-frame here.
6238          * Receiver will miss it and start proper recovery
6239          * procedures and ask for retransmission.
6240          */
6241         if (l2cap_check_fcs(chan, skb))
6242                 goto drop;
6243
6244         if (!control->sframe && control->sar == L2CAP_SAR_START)
6245                 len -= L2CAP_SDULEN_SIZE;
6246
6247         if (chan->fcs == L2CAP_FCS_CRC16)
6248                 len -= L2CAP_FCS_SIZE;
6249
6250         if (len > chan->mps) {
6251                 l2cap_send_disconn_req(chan, ECONNRESET);
6252                 goto drop;
6253         }
6254
6255         if (!control->sframe) {
6256                 int err;
6257
6258                 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6259                        control->sar, control->reqseq, control->final,
6260                        control->txseq);
6261
6262                 /* Validate F-bit - F=0 always valid, F=1 only
6263                  * valid in TX WAIT_F
6264                  */
6265                 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6266                         goto drop;
6267
6268                 if (chan->mode != L2CAP_MODE_STREAMING) {
6269                         event = L2CAP_EV_RECV_IFRAME;
6270                         err = l2cap_rx(chan, control, skb, event);
6271                 } else {
6272                         err = l2cap_stream_rx(chan, control, skb);
6273                 }
6274
6275                 if (err)
6276                         l2cap_send_disconn_req(chan, ECONNRESET);
6277         } else {
6278                 const u8 rx_func_to_event[4] = {
6279                         L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6280                         L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6281                 };
6282
6283                 /* Only I-frames are expected in streaming mode */
6284                 if (chan->mode == L2CAP_MODE_STREAMING)
6285                         goto drop;
6286
6287                 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6288                        control->reqseq, control->final, control->poll,
6289                        control->super);
6290
6291                 if (len != 0) {
6292                         BT_ERR("Trailing bytes: %d in sframe", len);
6293                         l2cap_send_disconn_req(chan, ECONNRESET);
6294                         goto drop;
6295                 }
6296
6297                 /* Validate F and P bits */
6298                 if (control->final && (control->poll ||
6299                                        chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6300                         goto drop;
6301
6302                 event = rx_func_to_event[control->super];
6303                 if (l2cap_rx(chan, control, skb, event))
6304                         l2cap_send_disconn_req(chan, ECONNRESET);
6305         }
6306
6307         return 0;
6308
6309 drop:
6310         kfree_skb(skb);
6311         return 0;
6312 }
6313
6314 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6315                                struct sk_buff *skb)
6316 {
6317         struct l2cap_chan *chan;
6318
6319         chan = l2cap_get_chan_by_scid(conn, cid);
6320         if (!chan) {
6321                 if (cid == L2CAP_CID_A2MP) {
6322                         chan = a2mp_channel_create(conn, skb);
6323                         if (!chan) {
6324                                 kfree_skb(skb);
6325                                 return;
6326                         }
6327
6328                         l2cap_chan_lock(chan);
6329                 } else {
6330                         BT_DBG("unknown cid 0x%4.4x", cid);
6331                         /* Drop packet and return */
6332                         kfree_skb(skb);
6333                         return;
6334                 }
6335         }
6336
6337         BT_DBG("chan %p, len %d", chan, skb->len);
6338
6339         if (chan->state != BT_CONNECTED)
6340                 goto drop;
6341
6342         switch (chan->mode) {
6343         case L2CAP_MODE_BASIC:
6344                 /* If socket recv buffers overflows we drop data here
6345                  * which is *bad* because L2CAP has to be reliable.
6346                  * But we don't have any other choice. L2CAP doesn't
6347                  * provide flow control mechanism. */
6348
6349                 if (chan->imtu < skb->len)
6350                         goto drop;
6351
6352                 if (!chan->ops->recv(chan, skb))
6353                         goto done;
6354                 break;
6355
6356         case L2CAP_MODE_ERTM:
6357         case L2CAP_MODE_STREAMING:
6358                 l2cap_data_rcv(chan, skb);
6359                 goto done;
6360
6361         default:
6362                 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6363                 break;
6364         }
6365
6366 drop:
6367         kfree_skb(skb);
6368
6369 done:
6370         l2cap_chan_unlock(chan);
6371 }
6372
6373 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6374                                   struct sk_buff *skb)
6375 {
6376         struct l2cap_chan *chan;
6377
6378         chan = l2cap_global_chan_by_psm(0, psm, conn->src, conn->dst);
6379         if (!chan)
6380                 goto drop;
6381
6382         BT_DBG("chan %p, len %d", chan, skb->len);
6383
6384         if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6385                 goto drop;
6386
6387         if (chan->imtu < skb->len)
6388                 goto drop;
6389
6390         if (!chan->ops->recv(chan, skb))
6391                 return;
6392
6393 drop:
6394         kfree_skb(skb);
6395 }
6396
6397 static void l2cap_att_channel(struct l2cap_conn *conn,
6398                               struct sk_buff *skb)
6399 {
6400         struct l2cap_chan *chan;
6401
6402         chan = l2cap_global_chan_by_scid(BT_CONNECTED, L2CAP_CID_ATT,
6403                                          conn->src, conn->dst);
6404         if (!chan)
6405                 goto drop;
6406
6407         BT_DBG("chan %p, len %d", chan, skb->len);
6408
6409         if (chan->imtu < skb->len)
6410                 goto drop;
6411
6412         if (!chan->ops->recv(chan, skb))
6413                 return;
6414
6415 drop:
6416         kfree_skb(skb);
6417 }
6418
6419 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6420 {
6421         struct l2cap_hdr *lh = (void *) skb->data;
6422         u16 cid, len;
6423         __le16 psm;
6424
6425         skb_pull(skb, L2CAP_HDR_SIZE);
6426         cid = __le16_to_cpu(lh->cid);
6427         len = __le16_to_cpu(lh->len);
6428
6429         if (len != skb->len) {
6430                 kfree_skb(skb);
6431                 return;
6432         }
6433
6434         BT_DBG("len %d, cid 0x%4.4x", len, cid);
6435
6436         switch (cid) {
6437         case L2CAP_CID_LE_SIGNALING:
6438                 l2cap_le_sig_channel(conn, skb);
6439                 break;
6440         case L2CAP_CID_SIGNALING:
6441                 l2cap_sig_channel(conn, skb);
6442                 break;
6443
6444         case L2CAP_CID_CONN_LESS:
6445                 psm = get_unaligned((__le16 *) skb->data);
6446                 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6447                 l2cap_conless_channel(conn, psm, skb);
6448                 break;
6449
6450         case L2CAP_CID_ATT:
6451                 l2cap_att_channel(conn, skb);
6452                 break;
6453
6454         case L2CAP_CID_SMP:
6455                 if (smp_sig_channel(conn, skb))
6456                         l2cap_conn_del(conn->hcon, EACCES);
6457                 break;
6458
6459         default:
6460                 l2cap_data_channel(conn, cid, skb);
6461                 break;
6462         }
6463 }
6464
6465 /* ---- L2CAP interface with lower layer (HCI) ---- */
6466
6467 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
6468 {
6469         int exact = 0, lm1 = 0, lm2 = 0;
6470         struct l2cap_chan *c;
6471
6472         BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
6473
6474         /* Find listening sockets and check their link_mode */
6475         read_lock(&chan_list_lock);
6476         list_for_each_entry(c, &chan_list, global_l) {
6477                 struct sock *sk = c->sk;
6478
6479                 if (c->state != BT_LISTEN)
6480                         continue;
6481
6482                 if (!bacmp(&bt_sk(sk)->src, &hdev->bdaddr)) {
6483                         lm1 |= HCI_LM_ACCEPT;
6484                         if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
6485                                 lm1 |= HCI_LM_MASTER;
6486                         exact++;
6487                 } else if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY)) {
6488                         lm2 |= HCI_LM_ACCEPT;
6489                         if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
6490                                 lm2 |= HCI_LM_MASTER;
6491                 }
6492         }
6493         read_unlock(&chan_list_lock);
6494
6495         return exact ? lm1 : lm2;
6496 }
6497
6498 void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
6499 {
6500         struct l2cap_conn *conn;
6501
6502         BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
6503
6504         if (!status) {
6505                 conn = l2cap_conn_add(hcon);
6506                 if (conn)
6507                         l2cap_conn_ready(conn);
6508         } else {
6509                 l2cap_conn_del(hcon, bt_to_errno(status));
6510         }
6511 }
6512
6513 int l2cap_disconn_ind(struct hci_conn *hcon)
6514 {
6515         struct l2cap_conn *conn = hcon->l2cap_data;
6516
6517         BT_DBG("hcon %p", hcon);
6518
6519         if (!conn)
6520                 return HCI_ERROR_REMOTE_USER_TERM;
6521         return conn->disc_reason;
6522 }
6523
6524 void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
6525 {
6526         BT_DBG("hcon %p reason %d", hcon, reason);
6527
6528         l2cap_conn_del(hcon, bt_to_errno(reason));
6529 }
6530
6531 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
6532 {
6533         if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
6534                 return;
6535
6536         if (encrypt == 0x00) {
6537                 if (chan->sec_level == BT_SECURITY_MEDIUM) {
6538                         __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
6539                 } else if (chan->sec_level == BT_SECURITY_HIGH)
6540                         l2cap_chan_close(chan, ECONNREFUSED);
6541         } else {
6542                 if (chan->sec_level == BT_SECURITY_MEDIUM)
6543                         __clear_chan_timer(chan);
6544         }
6545 }
6546
6547 int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
6548 {
6549         struct l2cap_conn *conn = hcon->l2cap_data;
6550         struct l2cap_chan *chan;
6551
6552         if (!conn)
6553                 return 0;
6554
6555         BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
6556
6557         if (hcon->type == LE_LINK) {
6558                 if (!status && encrypt)
6559                         smp_distribute_keys(conn, 0);
6560                 cancel_delayed_work(&conn->security_timer);
6561         }
6562
6563         mutex_lock(&conn->chan_lock);
6564
6565         list_for_each_entry(chan, &conn->chan_l, list) {
6566                 l2cap_chan_lock(chan);
6567
6568                 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
6569                        state_to_string(chan->state));
6570
6571                 if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
6572                         l2cap_chan_unlock(chan);
6573                         continue;
6574                 }
6575
6576                 if (chan->scid == L2CAP_CID_ATT) {
6577                         if (!status && encrypt) {
6578                                 chan->sec_level = hcon->sec_level;
6579                                 l2cap_chan_ready(chan);
6580                         }
6581
6582                         l2cap_chan_unlock(chan);
6583                         continue;
6584                 }
6585
6586                 if (!__l2cap_no_conn_pending(chan)) {
6587                         l2cap_chan_unlock(chan);
6588                         continue;
6589                 }
6590
6591                 if (!status && (chan->state == BT_CONNECTED ||
6592                                 chan->state == BT_CONFIG)) {
6593                         struct sock *sk = chan->sk;
6594
6595                         clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
6596                         sk->sk_state_change(sk);
6597
6598                         l2cap_check_encryption(chan, encrypt);
6599                         l2cap_chan_unlock(chan);
6600                         continue;
6601                 }
6602
6603                 if (chan->state == BT_CONNECT) {
6604                         if (!status) {
6605                                 l2cap_start_connection(chan);
6606                         } else {
6607                                 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
6608                         }
6609                 } else if (chan->state == BT_CONNECT2) {
6610                         struct sock *sk = chan->sk;
6611                         struct l2cap_conn_rsp rsp;
6612                         __u16 res, stat;
6613
6614                         lock_sock(sk);
6615
6616                         if (!status) {
6617                                 if (test_bit(BT_SK_DEFER_SETUP,
6618                                              &bt_sk(sk)->flags)) {
6619                                         res = L2CAP_CR_PEND;
6620                                         stat = L2CAP_CS_AUTHOR_PEND;
6621                                         chan->ops->defer(chan);
6622                                 } else {
6623                                         __l2cap_state_change(chan, BT_CONFIG);
6624                                         res = L2CAP_CR_SUCCESS;
6625                                         stat = L2CAP_CS_NO_INFO;
6626                                 }
6627                         } else {
6628                                 __l2cap_state_change(chan, BT_DISCONN);
6629                                 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
6630                                 res = L2CAP_CR_SEC_BLOCK;
6631                                 stat = L2CAP_CS_NO_INFO;
6632                         }
6633
6634                         release_sock(sk);
6635
6636                         rsp.scid   = cpu_to_le16(chan->dcid);
6637                         rsp.dcid   = cpu_to_le16(chan->scid);
6638                         rsp.result = cpu_to_le16(res);
6639                         rsp.status = cpu_to_le16(stat);
6640                         l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
6641                                        sizeof(rsp), &rsp);
6642
6643                         if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
6644                             res == L2CAP_CR_SUCCESS) {
6645                                 char buf[128];
6646                                 set_bit(CONF_REQ_SENT, &chan->conf_state);
6647                                 l2cap_send_cmd(conn, l2cap_get_ident(conn),
6648                                                L2CAP_CONF_REQ,
6649                                                l2cap_build_conf_req(chan, buf),
6650                                                buf);
6651                                 chan->num_conf_req++;
6652                         }
6653                 }
6654
6655                 l2cap_chan_unlock(chan);
6656         }
6657
6658         mutex_unlock(&conn->chan_lock);
6659
6660         return 0;
6661 }
6662
6663 int l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
6664 {
6665         struct l2cap_conn *conn = hcon->l2cap_data;
6666         struct l2cap_hdr *hdr;
6667         int len;
6668
6669         /* For AMP controller do not create l2cap conn */
6670         if (!conn && hcon->hdev->dev_type != HCI_BREDR)
6671                 goto drop;
6672
6673         if (!conn)
6674                 conn = l2cap_conn_add(hcon);
6675
6676         if (!conn)
6677                 goto drop;
6678
6679         BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
6680
6681         switch (flags) {
6682         case ACL_START:
6683         case ACL_START_NO_FLUSH:
6684         case ACL_COMPLETE:
6685                 if (conn->rx_len) {
6686                         BT_ERR("Unexpected start frame (len %d)", skb->len);
6687                         kfree_skb(conn->rx_skb);
6688                         conn->rx_skb = NULL;
6689                         conn->rx_len = 0;
6690                         l2cap_conn_unreliable(conn, ECOMM);
6691                 }
6692
6693                 /* Start fragment always begin with Basic L2CAP header */
6694                 if (skb->len < L2CAP_HDR_SIZE) {
6695                         BT_ERR("Frame is too short (len %d)", skb->len);
6696                         l2cap_conn_unreliable(conn, ECOMM);
6697                         goto drop;
6698                 }
6699
6700                 hdr = (struct l2cap_hdr *) skb->data;
6701                 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
6702
6703                 if (len == skb->len) {
6704                         /* Complete frame received */
6705                         l2cap_recv_frame(conn, skb);
6706                         return 0;
6707                 }
6708
6709                 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
6710
6711                 if (skb->len > len) {
6712                         BT_ERR("Frame is too long (len %d, expected len %d)",
6713                                skb->len, len);
6714                         l2cap_conn_unreliable(conn, ECOMM);
6715                         goto drop;
6716                 }
6717
6718                 /* Allocate skb for the complete frame (with header) */
6719                 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
6720                 if (!conn->rx_skb)
6721                         goto drop;
6722
6723                 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
6724                                           skb->len);
6725                 conn->rx_len = len - skb->len;
6726                 break;
6727
6728         case ACL_CONT:
6729                 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
6730
6731                 if (!conn->rx_len) {
6732                         BT_ERR("Unexpected continuation frame (len %d)", skb->len);
6733                         l2cap_conn_unreliable(conn, ECOMM);
6734                         goto drop;
6735                 }
6736
6737                 if (skb->len > conn->rx_len) {
6738                         BT_ERR("Fragment is too long (len %d, expected %d)",
6739                                skb->len, conn->rx_len);
6740                         kfree_skb(conn->rx_skb);
6741                         conn->rx_skb = NULL;
6742                         conn->rx_len = 0;
6743                         l2cap_conn_unreliable(conn, ECOMM);
6744                         goto drop;
6745                 }
6746
6747                 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
6748                                           skb->len);
6749                 conn->rx_len -= skb->len;
6750
6751                 if (!conn->rx_len) {
6752                         /* Complete frame received */
6753                         l2cap_recv_frame(conn, conn->rx_skb);
6754                         conn->rx_skb = NULL;
6755                 }
6756                 break;
6757         }
6758
6759 drop:
6760         kfree_skb(skb);
6761         return 0;
6762 }
6763
6764 static int l2cap_debugfs_show(struct seq_file *f, void *p)
6765 {
6766         struct l2cap_chan *c;
6767
6768         read_lock(&chan_list_lock);
6769
6770         list_for_each_entry(c, &chan_list, global_l) {
6771                 struct sock *sk = c->sk;
6772
6773                 seq_printf(f, "%pMR %pMR %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
6774                            &bt_sk(sk)->src, &bt_sk(sk)->dst,
6775                            c->state, __le16_to_cpu(c->psm),
6776                            c->scid, c->dcid, c->imtu, c->omtu,
6777                            c->sec_level, c->mode);
6778         }
6779
6780         read_unlock(&chan_list_lock);
6781
6782         return 0;
6783 }
6784
6785 static int l2cap_debugfs_open(struct inode *inode, struct file *file)
6786 {
6787         return single_open(file, l2cap_debugfs_show, inode->i_private);
6788 }
6789
6790 static const struct file_operations l2cap_debugfs_fops = {
6791         .open           = l2cap_debugfs_open,
6792         .read           = seq_read,
6793         .llseek         = seq_lseek,
6794         .release        = single_release,
6795 };
6796
6797 static struct dentry *l2cap_debugfs;
6798
6799 int __init l2cap_init(void)
6800 {
6801         int err;
6802
6803         err = l2cap_init_sockets();
6804         if (err < 0)
6805                 return err;
6806
6807         if (bt_debugfs) {
6808                 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
6809                                                     NULL, &l2cap_debugfs_fops);
6810                 if (!l2cap_debugfs)
6811                         BT_ERR("Failed to create L2CAP debug file");
6812         }
6813
6814         return 0;
6815 }
6816
6817 void l2cap_exit(void)
6818 {
6819         debugfs_remove(l2cap_debugfs);
6820         l2cap_cleanup_sockets();
6821 }
6822
6823 module_param(disable_ertm, bool, 0644);
6824 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");