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#include <linux/filter.h> 36 37#include <net/bluetooth/bluetooth.h> 38#include <net/bluetooth/hci_core.h> 39#include <net/bluetooth/l2cap.h> 40 41#include "smp.h" 42#include "a2mp.h" 43#include "amp.h" 44 45#define LE_FLOWCTL_MAX_CREDITS 65535 46 47bool disable_ertm; 48bool enable_ecred; 49 50static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD; 51 52static LIST_HEAD(chan_list); 53static DEFINE_RWLOCK(chan_list_lock); 54 55static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, 56 u8 code, u8 ident, u16 dlen, void *data); 57static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, 58 void *data); 59static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size); 60static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err); 61 62static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control, 63 struct sk_buff_head *skbs, u8 event); 64static void l2cap_retrans_timeout(struct work_struct *work); 65static void l2cap_monitor_timeout(struct work_struct *work); 66static void l2cap_ack_timeout(struct work_struct *work); 67 68static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type) 69{ 70 if (link_type == LE_LINK) { 71 if (bdaddr_type == ADDR_LE_DEV_PUBLIC) 72 return BDADDR_LE_PUBLIC; 73 else 74 return BDADDR_LE_RANDOM; 75 } 76 77 return BDADDR_BREDR; 78} 79 80static inline u8 bdaddr_src_type(struct hci_conn *hcon) 81{ 82 return bdaddr_type(hcon->type, hcon->src_type); 83} 84 85static inline u8 bdaddr_dst_type(struct hci_conn *hcon) 86{ 87 return bdaddr_type(hcon->type, hcon->dst_type); 88} 89 90/* ---- L2CAP channels ---- */ 91 92static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn, 93 u16 cid) 94{ 95 struct l2cap_chan *c; 96 97 list_for_each_entry(c, &conn->chan_l, list) { 98 if (c->dcid == cid) 99 return c; 100 } 101 return NULL; 102} 103 104static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn, 105 u16 cid) 106{ 107 struct l2cap_chan *c; 108 109 list_for_each_entry(c, &conn->chan_l, list) { 110 if (c->scid == cid) 111 return c; 112 } 113 return NULL; 114} 115 116/* Find channel with given SCID. 117 * Returns a reference locked channel. 118 */ 119static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn, 120 u16 cid) 121{ 122 struct l2cap_chan *c; 123 124 mutex_lock(&conn->chan_lock); 125 c = __l2cap_get_chan_by_scid(conn, cid); 126 if (c) { 127 /* Only lock if chan reference is not 0 */ 128 c = l2cap_chan_hold_unless_zero(c); 129 if (c) 130 l2cap_chan_lock(c); 131 } 132 mutex_unlock(&conn->chan_lock); 133 134 return c; 135} 136 137/* Find channel with given DCID. 138 * Returns a reference locked channel. 139 */ 140static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn, 141 u16 cid) 142{ 143 struct l2cap_chan *c; 144 145 mutex_lock(&conn->chan_lock); 146 c = __l2cap_get_chan_by_dcid(conn, cid); 147 if (c) { 148 /* Only lock if chan reference is not 0 */ 149 c = l2cap_chan_hold_unless_zero(c); 150 if (c) 151 l2cap_chan_lock(c); 152 } 153 mutex_unlock(&conn->chan_lock); 154 155 return c; 156} 157 158static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn, 159 u8 ident) 160{ 161 struct l2cap_chan *c; 162 163 list_for_each_entry(c, &conn->chan_l, list) { 164 if (c->ident == ident) 165 return c; 166 } 167 return NULL; 168} 169 170static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn, 171 u8 ident) 172{ 173 struct l2cap_chan *c; 174 175 mutex_lock(&conn->chan_lock); 176 c = __l2cap_get_chan_by_ident(conn, ident); 177 if (c) { 178 /* Only lock if chan reference is not 0 */ 179 c = l2cap_chan_hold_unless_zero(c); 180 if (c) 181 l2cap_chan_lock(c); 182 } 183 mutex_unlock(&conn->chan_lock); 184 185 return c; 186} 187 188static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src, 189 u8 src_type) 190{ 191 struct l2cap_chan *c; 192 193 list_for_each_entry(c, &chan_list, global_l) { 194 if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR) 195 continue; 196 197 if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR) 198 continue; 199 200 if (c->sport == psm && !bacmp(&c->src, src)) 201 return c; 202 } 203 return NULL; 204} 205 206int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm) 207{ 208 int err; 209 210 write_lock(&chan_list_lock); 211 212 if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) { 213 err = -EADDRINUSE; 214 goto done; 215 } 216 217 if (psm) { 218 chan->psm = psm; 219 chan->sport = psm; 220 err = 0; 221 } else { 222 u16 p, start, end, incr; 223 224 if (chan->src_type == BDADDR_BREDR) { 225 start = L2CAP_PSM_DYN_START; 226 end = L2CAP_PSM_AUTO_END; 227 incr = 2; 228 } else { 229 start = L2CAP_PSM_LE_DYN_START; 230 end = L2CAP_PSM_LE_DYN_END; 231 incr = 1; 232 } 233 234 err = -EINVAL; 235 for (p = start; p <= end; p += incr) 236 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src, 237 chan->src_type)) { 238 chan->psm = cpu_to_le16(p); 239 chan->sport = cpu_to_le16(p); 240 err = 0; 241 break; 242 } 243 } 244 245done: 246 write_unlock(&chan_list_lock); 247 return err; 248} 249EXPORT_SYMBOL_GPL(l2cap_add_psm); 250 251int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid) 252{ 253 write_lock(&chan_list_lock); 254 255 /* Override the defaults (which are for conn-oriented) */ 256 chan->omtu = L2CAP_DEFAULT_MTU; 257 chan->chan_type = L2CAP_CHAN_FIXED; 258 259 chan->scid = scid; 260 261 write_unlock(&chan_list_lock); 262 263 return 0; 264} 265 266static u16 l2cap_alloc_cid(struct l2cap_conn *conn) 267{ 268 u16 cid, dyn_end; 269 270 if (conn->hcon->type == LE_LINK) 271 dyn_end = L2CAP_CID_LE_DYN_END; 272 else 273 dyn_end = L2CAP_CID_DYN_END; 274 275 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) { 276 if (!__l2cap_get_chan_by_scid(conn, cid)) 277 return cid; 278 } 279 280 return 0; 281} 282 283static void l2cap_state_change(struct l2cap_chan *chan, int state) 284{ 285 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state), 286 state_to_string(state)); 287 288 chan->state = state; 289 chan->ops->state_change(chan, state, 0); 290} 291 292static inline void l2cap_state_change_and_error(struct l2cap_chan *chan, 293 int state, int err) 294{ 295 chan->state = state; 296 chan->ops->state_change(chan, chan->state, err); 297} 298 299static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err) 300{ 301 chan->ops->state_change(chan, chan->state, err); 302} 303 304static void __set_retrans_timer(struct l2cap_chan *chan) 305{ 306 if (!delayed_work_pending(&chan->monitor_timer) && 307 chan->retrans_timeout) { 308 l2cap_set_timer(chan, &chan->retrans_timer, 309 msecs_to_jiffies(chan->retrans_timeout)); 310 } 311} 312 313static void __set_monitor_timer(struct l2cap_chan *chan) 314{ 315 __clear_retrans_timer(chan); 316 if (chan->monitor_timeout) { 317 l2cap_set_timer(chan, &chan->monitor_timer, 318 msecs_to_jiffies(chan->monitor_timeout)); 319 } 320} 321 322static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head, 323 u16 seq) 324{ 325 struct sk_buff *skb; 326 327 skb_queue_walk(head, skb) { 328 if (bt_cb(skb)->l2cap.txseq == seq) 329 return skb; 330 } 331 332 return NULL; 333} 334 335/* ---- L2CAP sequence number lists ---- */ 336 337/* For ERTM, ordered lists of sequence numbers must be tracked for 338 * SREJ requests that are received and for frames that are to be 339 * retransmitted. These seq_list functions implement a singly-linked 340 * list in an array, where membership in the list can also be checked 341 * in constant time. Items can also be added to the tail of the list 342 * and removed from the head in constant time, without further memory 343 * allocs or frees. 344 */ 345 346static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size) 347{ 348 size_t alloc_size, i; 349 350 /* Allocated size is a power of 2 to map sequence numbers 351 * (which may be up to 14 bits) in to a smaller array that is 352 * sized for the negotiated ERTM transmit windows. 353 */ 354 alloc_size = roundup_pow_of_two(size); 355 356 seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL); 357 if (!seq_list->list) 358 return -ENOMEM; 359 360 seq_list->mask = alloc_size - 1; 361 seq_list->head = L2CAP_SEQ_LIST_CLEAR; 362 seq_list->tail = L2CAP_SEQ_LIST_CLEAR; 363 for (i = 0; i < alloc_size; i++) 364 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR; 365 366 return 0; 367} 368 369static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list) 370{ 371 kfree(seq_list->list); 372} 373 374static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list, 375 u16 seq) 376{ 377 /* Constant-time check for list membership */ 378 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR; 379} 380 381static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list) 382{ 383 u16 seq = seq_list->head; 384 u16 mask = seq_list->mask; 385 386 seq_list->head = seq_list->list[seq & mask]; 387 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR; 388 389 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) { 390 seq_list->head = L2CAP_SEQ_LIST_CLEAR; 391 seq_list->tail = L2CAP_SEQ_LIST_CLEAR; 392 } 393 394 return seq; 395} 396 397static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list) 398{ 399 u16 i; 400 401 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR) 402 return; 403 404 for (i = 0; i <= seq_list->mask; i++) 405 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR; 406 407 seq_list->head = L2CAP_SEQ_LIST_CLEAR; 408 seq_list->tail = L2CAP_SEQ_LIST_CLEAR; 409} 410 411static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq) 412{ 413 u16 mask = seq_list->mask; 414 415 /* All appends happen in constant time */ 416 417 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR) 418 return; 419 420 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR) 421 seq_list->head = seq; 422 else 423 seq_list->list[seq_list->tail & mask] = seq; 424 425 seq_list->tail = seq; 426 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL; 427} 428 429static void l2cap_chan_timeout(struct work_struct *work) 430{ 431 struct l2cap_chan *chan = container_of(work, struct l2cap_chan, 432 chan_timer.work); 433 struct l2cap_conn *conn = chan->conn; 434 int reason; 435 436 BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); 437 438 if (!conn) 439 return; 440 441 mutex_lock(&conn->chan_lock); 442 /* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling 443 * this work. No need to call l2cap_chan_hold(chan) here again. 444 */ 445 l2cap_chan_lock(chan); 446 447 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG) 448 reason = ECONNREFUSED; 449 else if (chan->state == BT_CONNECT && 450 chan->sec_level != BT_SECURITY_SDP) 451 reason = ECONNREFUSED; 452 else 453 reason = ETIMEDOUT; 454 455 l2cap_chan_close(chan, reason); 456 457 chan->ops->close(chan); 458 459 l2cap_chan_unlock(chan); 460 l2cap_chan_put(chan); 461 462 mutex_unlock(&conn->chan_lock); 463} 464 465struct l2cap_chan *l2cap_chan_create(void) 466{ 467 struct l2cap_chan *chan; 468 469 chan = kzalloc(sizeof(*chan), GFP_ATOMIC); 470 if (!chan) 471 return NULL; 472 473 skb_queue_head_init(&chan->tx_q); 474 skb_queue_head_init(&chan->srej_q); 475 mutex_init(&chan->lock); 476 477 /* Set default lock nesting level */ 478 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL); 479 480 write_lock(&chan_list_lock); 481 list_add(&chan->global_l, &chan_list); 482 write_unlock(&chan_list_lock); 483 484 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout); 485 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout); 486 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout); 487 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout); 488 489 chan->state = BT_OPEN; 490 491 kref_init(&chan->kref); 492 493 /* This flag is cleared in l2cap_chan_ready() */ 494 set_bit(CONF_NOT_COMPLETE, &chan->conf_state); 495 496 BT_DBG("chan %p", chan); 497 498 return chan; 499} 500EXPORT_SYMBOL_GPL(l2cap_chan_create); 501 502static void l2cap_chan_destroy(struct kref *kref) 503{ 504 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref); 505 506 BT_DBG("chan %p", chan); 507 508 write_lock(&chan_list_lock); 509 list_del(&chan->global_l); 510 write_unlock(&chan_list_lock); 511 512 kfree(chan); 513} 514 515void l2cap_chan_hold(struct l2cap_chan *c) 516{ 517 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref)); 518 519 kref_get(&c->kref); 520} 521 522struct l2cap_chan *l2cap_chan_hold_unless_zero(struct l2cap_chan *c) 523{ 524 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref)); 525 526 if (!kref_get_unless_zero(&c->kref)) 527 return NULL; 528 529 return c; 530} 531 532void l2cap_chan_put(struct l2cap_chan *c) 533{ 534 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref)); 535 536 kref_put(&c->kref, l2cap_chan_destroy); 537} 538EXPORT_SYMBOL_GPL(l2cap_chan_put); 539 540void l2cap_chan_set_defaults(struct l2cap_chan *chan) 541{ 542 chan->fcs = L2CAP_FCS_CRC16; 543 chan->max_tx = L2CAP_DEFAULT_MAX_TX; 544 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW; 545 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW; 546 chan->remote_max_tx = chan->max_tx; 547 chan->remote_tx_win = chan->tx_win; 548 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW; 549 chan->sec_level = BT_SECURITY_LOW; 550 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO; 551 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO; 552 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO; 553 554 chan->conf_state = 0; 555 set_bit(CONF_NOT_COMPLETE, &chan->conf_state); 556 557 set_bit(FLAG_FORCE_ACTIVE, &chan->flags); 558} 559EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults); 560 561static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits) 562{ 563 chan->sdu = NULL; 564 chan->sdu_last_frag = NULL; 565 chan->sdu_len = 0; 566 chan->tx_credits = tx_credits; 567 /* Derive MPS from connection MTU to stop HCI fragmentation */ 568 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE); 569 /* Give enough credits for a full packet */ 570 chan->rx_credits = (chan->imtu / chan->mps) + 1; 571 572 skb_queue_head_init(&chan->tx_q); 573} 574 575static void l2cap_ecred_init(struct l2cap_chan *chan, u16 tx_credits) 576{ 577 l2cap_le_flowctl_init(chan, tx_credits); 578 579 /* L2CAP implementations shall support a minimum MPS of 64 octets */ 580 if (chan->mps < L2CAP_ECRED_MIN_MPS) { 581 chan->mps = L2CAP_ECRED_MIN_MPS; 582 chan->rx_credits = (chan->imtu / chan->mps) + 1; 583 } 584} 585 586void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan) 587{ 588 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn, 589 __le16_to_cpu(chan->psm), chan->dcid); 590 591 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM; 592 593 chan->conn = conn; 594 595 switch (chan->chan_type) { 596 case L2CAP_CHAN_CONN_ORIENTED: 597 /* Alloc CID for connection-oriented socket */ 598 chan->scid = l2cap_alloc_cid(conn); 599 if (conn->hcon->type == ACL_LINK) 600 chan->omtu = L2CAP_DEFAULT_MTU; 601 break; 602 603 case L2CAP_CHAN_CONN_LESS: 604 /* Connectionless socket */ 605 chan->scid = L2CAP_CID_CONN_LESS; 606 chan->dcid = L2CAP_CID_CONN_LESS; 607 chan->omtu = L2CAP_DEFAULT_MTU; 608 break; 609 610 case L2CAP_CHAN_FIXED: 611 /* Caller will set CID and CID specific MTU values */ 612 break; 613 614 default: 615 /* Raw socket can send/recv signalling messages only */ 616 chan->scid = L2CAP_CID_SIGNALING; 617 chan->dcid = L2CAP_CID_SIGNALING; 618 chan->omtu = L2CAP_DEFAULT_MTU; 619 } 620 621 chan->local_id = L2CAP_BESTEFFORT_ID; 622 chan->local_stype = L2CAP_SERV_BESTEFFORT; 623 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE; 624 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME; 625 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT; 626 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO; 627 628 l2cap_chan_hold(chan); 629 630 /* Only keep a reference for fixed channels if they requested it */ 631 if (chan->chan_type != L2CAP_CHAN_FIXED || 632 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags)) 633 hci_conn_hold(conn->hcon); 634 635 list_add(&chan->list, &conn->chan_l); 636} 637 638void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan) 639{ 640 mutex_lock(&conn->chan_lock); 641 __l2cap_chan_add(conn, chan); 642 mutex_unlock(&conn->chan_lock); 643} 644 645void l2cap_chan_del(struct l2cap_chan *chan, int err) 646{ 647 struct l2cap_conn *conn = chan->conn; 648 649 __clear_chan_timer(chan); 650 651 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err, 652 state_to_string(chan->state)); 653 654 chan->ops->teardown(chan, err); 655 656 if (conn) { 657 struct amp_mgr *mgr = conn->hcon->amp_mgr; 658 /* Delete from channel list */ 659 list_del(&chan->list); 660 661 l2cap_chan_put(chan); 662 663 chan->conn = NULL; 664 665 /* Reference was only held for non-fixed channels or 666 * fixed channels that explicitly requested it using the 667 * FLAG_HOLD_HCI_CONN flag. 668 */ 669 if (chan->chan_type != L2CAP_CHAN_FIXED || 670 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags)) 671 hci_conn_drop(conn->hcon); 672 673 if (mgr && mgr->bredr_chan == chan) 674 mgr->bredr_chan = NULL; 675 } 676 677 if (chan->hs_hchan) { 678 struct hci_chan *hs_hchan = chan->hs_hchan; 679 680 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan); 681 amp_disconnect_logical_link(hs_hchan); 682 } 683 684 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state)) 685 return; 686 687 switch(chan->mode) { 688 case L2CAP_MODE_BASIC: 689 break; 690 691 case L2CAP_MODE_LE_FLOWCTL: 692 case L2CAP_MODE_EXT_FLOWCTL: 693 skb_queue_purge(&chan->tx_q); 694 break; 695 696 case L2CAP_MODE_ERTM: 697 __clear_retrans_timer(chan); 698 __clear_monitor_timer(chan); 699 __clear_ack_timer(chan); 700 701 skb_queue_purge(&chan->srej_q); 702 703 l2cap_seq_list_free(&chan->srej_list); 704 l2cap_seq_list_free(&chan->retrans_list); 705 fallthrough; 706 707 case L2CAP_MODE_STREAMING: 708 skb_queue_purge(&chan->tx_q); 709 break; 710 } 711 712 return; 713} 714EXPORT_SYMBOL_GPL(l2cap_chan_del); 715 716static void __l2cap_chan_list_id(struct l2cap_conn *conn, u16 id, 717 l2cap_chan_func_t func, void *data) 718{ 719 struct l2cap_chan *chan, *l; 720 721 list_for_each_entry_safe(chan, l, &conn->chan_l, list) { 722 if (chan->ident == id) 723 func(chan, data); 724 } 725} 726 727static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, 728 void *data) 729{ 730 struct l2cap_chan *chan; 731 732 list_for_each_entry(chan, &conn->chan_l, list) { 733 func(chan, data); 734 } 735} 736 737void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, 738 void *data) 739{ 740 if (!conn) 741 return; 742 743 mutex_lock(&conn->chan_lock); 744 __l2cap_chan_list(conn, func, data); 745 mutex_unlock(&conn->chan_lock); 746} 747 748EXPORT_SYMBOL_GPL(l2cap_chan_list); 749 750static void l2cap_conn_update_id_addr(struct work_struct *work) 751{ 752 struct l2cap_conn *conn = container_of(work, struct l2cap_conn, 753 id_addr_update_work); 754 struct hci_conn *hcon = conn->hcon; 755 struct l2cap_chan *chan; 756 757 mutex_lock(&conn->chan_lock); 758 759 list_for_each_entry(chan, &conn->chan_l, list) { 760 l2cap_chan_lock(chan); 761 bacpy(&chan->dst, &hcon->dst); 762 chan->dst_type = bdaddr_dst_type(hcon); 763 l2cap_chan_unlock(chan); 764 } 765 766 mutex_unlock(&conn->chan_lock); 767} 768 769static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan) 770{ 771 struct l2cap_conn *conn = chan->conn; 772 struct l2cap_le_conn_rsp rsp; 773 u16 result; 774 775 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) 776 result = L2CAP_CR_LE_AUTHORIZATION; 777 else 778 result = L2CAP_CR_LE_BAD_PSM; 779 780 l2cap_state_change(chan, BT_DISCONN); 781 782 rsp.dcid = cpu_to_le16(chan->scid); 783 rsp.mtu = cpu_to_le16(chan->imtu); 784 rsp.mps = cpu_to_le16(chan->mps); 785 rsp.credits = cpu_to_le16(chan->rx_credits); 786 rsp.result = cpu_to_le16(result); 787 788 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), 789 &rsp); 790} 791 792static void l2cap_chan_ecred_connect_reject(struct l2cap_chan *chan) 793{ 794 l2cap_state_change(chan, BT_DISCONN); 795 796 __l2cap_ecred_conn_rsp_defer(chan); 797} 798 799static void l2cap_chan_connect_reject(struct l2cap_chan *chan) 800{ 801 struct l2cap_conn *conn = chan->conn; 802 struct l2cap_conn_rsp rsp; 803 u16 result; 804 805 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) 806 result = L2CAP_CR_SEC_BLOCK; 807 else 808 result = L2CAP_CR_BAD_PSM; 809 810 l2cap_state_change(chan, BT_DISCONN); 811 812 rsp.scid = cpu_to_le16(chan->dcid); 813 rsp.dcid = cpu_to_le16(chan->scid); 814 rsp.result = cpu_to_le16(result); 815 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 816 817 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp); 818} 819 820void l2cap_chan_close(struct l2cap_chan *chan, int reason) 821{ 822 struct l2cap_conn *conn = chan->conn; 823 824 BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); 825 826 switch (chan->state) { 827 case BT_LISTEN: 828 chan->ops->teardown(chan, 0); 829 break; 830 831 case BT_CONNECTED: 832 case BT_CONFIG: 833 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) { 834 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 835 l2cap_send_disconn_req(chan, reason); 836 } else 837 l2cap_chan_del(chan, reason); 838 break; 839 840 case BT_CONNECT2: 841 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) { 842 if (conn->hcon->type == ACL_LINK) 843 l2cap_chan_connect_reject(chan); 844 else if (conn->hcon->type == LE_LINK) { 845 switch (chan->mode) { 846 case L2CAP_MODE_LE_FLOWCTL: 847 l2cap_chan_le_connect_reject(chan); 848 break; 849 case L2CAP_MODE_EXT_FLOWCTL: 850 l2cap_chan_ecred_connect_reject(chan); 851 return; 852 } 853 } 854 } 855 856 l2cap_chan_del(chan, reason); 857 break; 858 859 case BT_CONNECT: 860 case BT_DISCONN: 861 l2cap_chan_del(chan, reason); 862 break; 863 864 default: 865 chan->ops->teardown(chan, 0); 866 break; 867 } 868} 869EXPORT_SYMBOL(l2cap_chan_close); 870 871static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan) 872{ 873 switch (chan->chan_type) { 874 case L2CAP_CHAN_RAW: 875 switch (chan->sec_level) { 876 case BT_SECURITY_HIGH: 877 case BT_SECURITY_FIPS: 878 return HCI_AT_DEDICATED_BONDING_MITM; 879 case BT_SECURITY_MEDIUM: 880 return HCI_AT_DEDICATED_BONDING; 881 default: 882 return HCI_AT_NO_BONDING; 883 } 884 break; 885 case L2CAP_CHAN_CONN_LESS: 886 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) { 887 if (chan->sec_level == BT_SECURITY_LOW) 888 chan->sec_level = BT_SECURITY_SDP; 889 } 890 if (chan->sec_level == BT_SECURITY_HIGH || 891 chan->sec_level == BT_SECURITY_FIPS) 892 return HCI_AT_NO_BONDING_MITM; 893 else 894 return HCI_AT_NO_BONDING; 895 break; 896 case L2CAP_CHAN_CONN_ORIENTED: 897 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) { 898 if (chan->sec_level == BT_SECURITY_LOW) 899 chan->sec_level = BT_SECURITY_SDP; 900 901 if (chan->sec_level == BT_SECURITY_HIGH || 902 chan->sec_level == BT_SECURITY_FIPS) 903 return HCI_AT_NO_BONDING_MITM; 904 else 905 return HCI_AT_NO_BONDING; 906 } 907 fallthrough; 908 909 default: 910 switch (chan->sec_level) { 911 case BT_SECURITY_HIGH: 912 case BT_SECURITY_FIPS: 913 return HCI_AT_GENERAL_BONDING_MITM; 914 case BT_SECURITY_MEDIUM: 915 return HCI_AT_GENERAL_BONDING; 916 default: 917 return HCI_AT_NO_BONDING; 918 } 919 break; 920 } 921} 922 923/* Service level security */ 924int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator) 925{ 926 struct l2cap_conn *conn = chan->conn; 927 __u8 auth_type; 928 929 if (conn->hcon->type == LE_LINK) 930 return smp_conn_security(conn->hcon, chan->sec_level); 931 932 auth_type = l2cap_get_auth_type(chan); 933 934 return hci_conn_security(conn->hcon, chan->sec_level, auth_type, 935 initiator); 936} 937 938static u8 l2cap_get_ident(struct l2cap_conn *conn) 939{ 940 u8 id; 941 942 /* Get next available identificator. 943 * 1 - 128 are used by kernel. 944 * 129 - 199 are reserved. 945 * 200 - 254 are used by utilities like l2ping, etc. 946 */ 947 948 mutex_lock(&conn->ident_lock); 949 950 if (++conn->tx_ident > 128) 951 conn->tx_ident = 1; 952 953 id = conn->tx_ident; 954 955 mutex_unlock(&conn->ident_lock); 956 957 return id; 958} 959 960static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, 961 void *data) 962{ 963 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data); 964 u8 flags; 965 966 BT_DBG("code 0x%2.2x", code); 967 968 if (!skb) 969 return; 970 971 /* Use NO_FLUSH if supported or we have an LE link (which does 972 * not support auto-flushing packets) */ 973 if (lmp_no_flush_capable(conn->hcon->hdev) || 974 conn->hcon->type == LE_LINK) 975 flags = ACL_START_NO_FLUSH; 976 else 977 flags = ACL_START; 978 979 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON; 980 skb->priority = HCI_PRIO_MAX; 981 982 hci_send_acl(conn->hchan, skb, flags); 983} 984 985static bool __chan_is_moving(struct l2cap_chan *chan) 986{ 987 return chan->move_state != L2CAP_MOVE_STABLE && 988 chan->move_state != L2CAP_MOVE_WAIT_PREPARE; 989} 990 991static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb) 992{ 993 struct hci_conn *hcon = chan->conn->hcon; 994 u16 flags; 995 996 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len, 997 skb->priority); 998 999 if (chan->hs_hcon && !__chan_is_moving(chan)) { 1000 if (chan->hs_hchan) 1001 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE); 1002 else 1003 kfree_skb(skb); 1004 1005 return; 1006 } 1007 1008 /* Use NO_FLUSH for LE links (where this is the only option) or 1009 * if the BR/EDR link supports it and flushing has not been 1010 * explicitly requested (through FLAG_FLUSHABLE). 1011 */ 1012 if (hcon->type == LE_LINK || 1013 (!test_bit(FLAG_FLUSHABLE, &chan->flags) && 1014 lmp_no_flush_capable(hcon->hdev))) 1015 flags = ACL_START_NO_FLUSH; 1016 else 1017 flags = ACL_START; 1018 1019 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags); 1020 hci_send_acl(chan->conn->hchan, skb, flags); 1021} 1022 1023static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control) 1024{ 1025 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT; 1026 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT; 1027 1028 if (enh & L2CAP_CTRL_FRAME_TYPE) { 1029 /* S-Frame */ 1030 control->sframe = 1; 1031 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT; 1032 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT; 1033 1034 control->sar = 0; 1035 control->txseq = 0; 1036 } else { 1037 /* I-Frame */ 1038 control->sframe = 0; 1039 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT; 1040 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT; 1041 1042 control->poll = 0; 1043 control->super = 0; 1044 } 1045} 1046 1047static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control) 1048{ 1049 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT; 1050 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT; 1051 1052 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) { 1053 /* S-Frame */ 1054 control->sframe = 1; 1055 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT; 1056 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT; 1057 1058 control->sar = 0; 1059 control->txseq = 0; 1060 } else { 1061 /* I-Frame */ 1062 control->sframe = 0; 1063 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT; 1064 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT; 1065 1066 control->poll = 0; 1067 control->super = 0; 1068 } 1069} 1070 1071static inline void __unpack_control(struct l2cap_chan *chan, 1072 struct sk_buff *skb) 1073{ 1074 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) { 1075 __unpack_extended_control(get_unaligned_le32(skb->data), 1076 &bt_cb(skb)->l2cap); 1077 skb_pull(skb, L2CAP_EXT_CTRL_SIZE); 1078 } else { 1079 __unpack_enhanced_control(get_unaligned_le16(skb->data), 1080 &bt_cb(skb)->l2cap); 1081 skb_pull(skb, L2CAP_ENH_CTRL_SIZE); 1082 } 1083} 1084 1085static u32 __pack_extended_control(struct l2cap_ctrl *control) 1086{ 1087 u32 packed; 1088 1089 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT; 1090 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT; 1091 1092 if (control->sframe) { 1093 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT; 1094 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT; 1095 packed |= L2CAP_EXT_CTRL_FRAME_TYPE; 1096 } else { 1097 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT; 1098 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT; 1099 } 1100 1101 return packed; 1102} 1103 1104static u16 __pack_enhanced_control(struct l2cap_ctrl *control) 1105{ 1106 u16 packed; 1107 1108 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT; 1109 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT; 1110 1111 if (control->sframe) { 1112 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT; 1113 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT; 1114 packed |= L2CAP_CTRL_FRAME_TYPE; 1115 } else { 1116 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT; 1117 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT; 1118 } 1119 1120 return packed; 1121} 1122 1123static inline void __pack_control(struct l2cap_chan *chan, 1124 struct l2cap_ctrl *control, 1125 struct sk_buff *skb) 1126{ 1127 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) { 1128 put_unaligned_le32(__pack_extended_control(control), 1129 skb->data + L2CAP_HDR_SIZE); 1130 } else { 1131 put_unaligned_le16(__pack_enhanced_control(control), 1132 skb->data + L2CAP_HDR_SIZE); 1133 } 1134} 1135 1136static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan) 1137{ 1138 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 1139 return L2CAP_EXT_HDR_SIZE; 1140 else 1141 return L2CAP_ENH_HDR_SIZE; 1142} 1143 1144static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan, 1145 u32 control) 1146{ 1147 struct sk_buff *skb; 1148 struct l2cap_hdr *lh; 1149 int hlen = __ertm_hdr_size(chan); 1150 1151 if (chan->fcs == L2CAP_FCS_CRC16) 1152 hlen += L2CAP_FCS_SIZE; 1153 1154 skb = bt_skb_alloc(hlen, GFP_KERNEL); 1155 1156 if (!skb) 1157 return ERR_PTR(-ENOMEM); 1158 1159 lh = skb_put(skb, L2CAP_HDR_SIZE); 1160 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE); 1161 lh->cid = cpu_to_le16(chan->dcid); 1162 1163 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 1164 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE)); 1165 else 1166 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE)); 1167 1168 if (chan->fcs == L2CAP_FCS_CRC16) { 1169 u16 fcs = crc16(0, (u8 *)skb->data, skb->len); 1170 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE)); 1171 } 1172 1173 skb->priority = HCI_PRIO_MAX; 1174 return skb; 1175} 1176 1177static void l2cap_send_sframe(struct l2cap_chan *chan, 1178 struct l2cap_ctrl *control) 1179{ 1180 struct sk_buff *skb; 1181 u32 control_field; 1182 1183 BT_DBG("chan %p, control %p", chan, control); 1184 1185 if (!control->sframe) 1186 return; 1187 1188 if (__chan_is_moving(chan)) 1189 return; 1190 1191 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) && 1192 !control->poll) 1193 control->final = 1; 1194 1195 if (control->super == L2CAP_SUPER_RR) 1196 clear_bit(CONN_RNR_SENT, &chan->conn_state); 1197 else if (control->super == L2CAP_SUPER_RNR) 1198 set_bit(CONN_RNR_SENT, &chan->conn_state); 1199 1200 if (control->super != L2CAP_SUPER_SREJ) { 1201 chan->last_acked_seq = control->reqseq; 1202 __clear_ack_timer(chan); 1203 } 1204 1205 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq, 1206 control->final, control->poll, control->super); 1207 1208 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 1209 control_field = __pack_extended_control(control); 1210 else 1211 control_field = __pack_enhanced_control(control); 1212 1213 skb = l2cap_create_sframe_pdu(chan, control_field); 1214 if (!IS_ERR(skb)) 1215 l2cap_do_send(chan, skb); 1216} 1217 1218static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll) 1219{ 1220 struct l2cap_ctrl control; 1221 1222 BT_DBG("chan %p, poll %d", chan, poll); 1223 1224 memset(&control, 0, sizeof(control)); 1225 control.sframe = 1; 1226 control.poll = poll; 1227 1228 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) 1229 control.super = L2CAP_SUPER_RNR; 1230 else 1231 control.super = L2CAP_SUPER_RR; 1232 1233 control.reqseq = chan->buffer_seq; 1234 l2cap_send_sframe(chan, &control); 1235} 1236 1237static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan) 1238{ 1239 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) 1240 return true; 1241 1242 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state); 1243} 1244 1245static bool __amp_capable(struct l2cap_chan *chan) 1246{ 1247 struct l2cap_conn *conn = chan->conn; 1248 struct hci_dev *hdev; 1249 bool amp_available = false; 1250 1251 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP)) 1252 return false; 1253 1254 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP)) 1255 return false; 1256 1257 read_lock(&hci_dev_list_lock); 1258 list_for_each_entry(hdev, &hci_dev_list, list) { 1259 if (hdev->amp_type != AMP_TYPE_BREDR && 1260 test_bit(HCI_UP, &hdev->flags)) { 1261 amp_available = true; 1262 break; 1263 } 1264 } 1265 read_unlock(&hci_dev_list_lock); 1266 1267 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED) 1268 return amp_available; 1269 1270 return false; 1271} 1272 1273static bool l2cap_check_efs(struct l2cap_chan *chan) 1274{ 1275 /* Check EFS parameters */ 1276 return true; 1277} 1278 1279void l2cap_send_conn_req(struct l2cap_chan *chan) 1280{ 1281 struct l2cap_conn *conn = chan->conn; 1282 struct l2cap_conn_req req; 1283 1284 req.scid = cpu_to_le16(chan->scid); 1285 req.psm = chan->psm; 1286 1287 chan->ident = l2cap_get_ident(conn); 1288 1289 set_bit(CONF_CONNECT_PEND, &chan->conf_state); 1290 1291 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req); 1292} 1293 1294static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id) 1295{ 1296 struct l2cap_create_chan_req req; 1297 req.scid = cpu_to_le16(chan->scid); 1298 req.psm = chan->psm; 1299 req.amp_id = amp_id; 1300 1301 chan->ident = l2cap_get_ident(chan->conn); 1302 1303 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ, 1304 sizeof(req), &req); 1305} 1306 1307static void l2cap_move_setup(struct l2cap_chan *chan) 1308{ 1309 struct sk_buff *skb; 1310 1311 BT_DBG("chan %p", chan); 1312 1313 if (chan->mode != L2CAP_MODE_ERTM) 1314 return; 1315 1316 __clear_retrans_timer(chan); 1317 __clear_monitor_timer(chan); 1318 __clear_ack_timer(chan); 1319 1320 chan->retry_count = 0; 1321 skb_queue_walk(&chan->tx_q, skb) { 1322 if (bt_cb(skb)->l2cap.retries) 1323 bt_cb(skb)->l2cap.retries = 1; 1324 else 1325 break; 1326 } 1327 1328 chan->expected_tx_seq = chan->buffer_seq; 1329 1330 clear_bit(CONN_REJ_ACT, &chan->conn_state); 1331 clear_bit(CONN_SREJ_ACT, &chan->conn_state); 1332 l2cap_seq_list_clear(&chan->retrans_list); 1333 l2cap_seq_list_clear(&chan->srej_list); 1334 skb_queue_purge(&chan->srej_q); 1335 1336 chan->tx_state = L2CAP_TX_STATE_XMIT; 1337 chan->rx_state = L2CAP_RX_STATE_MOVE; 1338 1339 set_bit(CONN_REMOTE_BUSY, &chan->conn_state); 1340} 1341 1342static void l2cap_move_done(struct l2cap_chan *chan) 1343{ 1344 u8 move_role = chan->move_role; 1345 BT_DBG("chan %p", chan); 1346 1347 chan->move_state = L2CAP_MOVE_STABLE; 1348 chan->move_role = L2CAP_MOVE_ROLE_NONE; 1349 1350 if (chan->mode != L2CAP_MODE_ERTM) 1351 return; 1352 1353 switch (move_role) { 1354 case L2CAP_MOVE_ROLE_INITIATOR: 1355 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL); 1356 chan->rx_state = L2CAP_RX_STATE_WAIT_F; 1357 break; 1358 case L2CAP_MOVE_ROLE_RESPONDER: 1359 chan->rx_state = L2CAP_RX_STATE_WAIT_P; 1360 break; 1361 } 1362} 1363 1364static void l2cap_chan_ready(struct l2cap_chan *chan) 1365{ 1366 /* The channel may have already been flagged as connected in 1367 * case of receiving data before the L2CAP info req/rsp 1368 * procedure is complete. 1369 */ 1370 if (chan->state == BT_CONNECTED) 1371 return; 1372 1373 /* This clears all conf flags, including CONF_NOT_COMPLETE */ 1374 chan->conf_state = 0; 1375 __clear_chan_timer(chan); 1376 1377 switch (chan->mode) { 1378 case L2CAP_MODE_LE_FLOWCTL: 1379 case L2CAP_MODE_EXT_FLOWCTL: 1380 if (!chan->tx_credits) 1381 chan->ops->suspend(chan); 1382 break; 1383 } 1384 1385 chan->state = BT_CONNECTED; 1386 1387 chan->ops->ready(chan); 1388} 1389 1390static void l2cap_le_connect(struct l2cap_chan *chan) 1391{ 1392 struct l2cap_conn *conn = chan->conn; 1393 struct l2cap_le_conn_req req; 1394 1395 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags)) 1396 return; 1397 1398 if (!chan->imtu) 1399 chan->imtu = chan->conn->mtu; 1400 1401 l2cap_le_flowctl_init(chan, 0); 1402 1403 req.psm = chan->psm; 1404 req.scid = cpu_to_le16(chan->scid); 1405 req.mtu = cpu_to_le16(chan->imtu); 1406 req.mps = cpu_to_le16(chan->mps); 1407 req.credits = cpu_to_le16(chan->rx_credits); 1408 1409 chan->ident = l2cap_get_ident(conn); 1410 1411 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ, 1412 sizeof(req), &req); 1413} 1414 1415struct l2cap_ecred_conn_data { 1416 struct { 1417 struct l2cap_ecred_conn_req req; 1418 __le16 scid[5]; 1419 } __packed pdu; 1420 struct l2cap_chan *chan; 1421 struct pid *pid; 1422 int count; 1423}; 1424 1425static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data) 1426{ 1427 struct l2cap_ecred_conn_data *conn = data; 1428 struct pid *pid; 1429 1430 if (chan == conn->chan) 1431 return; 1432 1433 if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags)) 1434 return; 1435 1436 pid = chan->ops->get_peer_pid(chan); 1437 1438 /* Only add deferred channels with the same PID/PSM */ 1439 if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident || 1440 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT) 1441 return; 1442 1443 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) 1444 return; 1445 1446 l2cap_ecred_init(chan, 0); 1447 1448 /* Set the same ident so we can match on the rsp */ 1449 chan->ident = conn->chan->ident; 1450 1451 /* Include all channels deferred */ 1452 conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid); 1453 1454 conn->count++; 1455} 1456 1457static void l2cap_ecred_connect(struct l2cap_chan *chan) 1458{ 1459 struct l2cap_conn *conn = chan->conn; 1460 struct l2cap_ecred_conn_data data; 1461 1462 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) 1463 return; 1464 1465 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) 1466 return; 1467 1468 l2cap_ecred_init(chan, 0); 1469 1470 memset(&data, 0, sizeof(data)); 1471 data.pdu.req.psm = chan->psm; 1472 data.pdu.req.mtu = cpu_to_le16(chan->imtu); 1473 data.pdu.req.mps = cpu_to_le16(chan->mps); 1474 data.pdu.req.credits = cpu_to_le16(chan->rx_credits); 1475 data.pdu.scid[0] = cpu_to_le16(chan->scid); 1476 1477 chan->ident = l2cap_get_ident(conn); 1478 data.pid = chan->ops->get_peer_pid(chan); 1479 1480 data.count = 1; 1481 data.chan = chan; 1482 data.pid = chan->ops->get_peer_pid(chan); 1483 1484 __l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data); 1485 1486 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ, 1487 sizeof(data.pdu.req) + data.count * sizeof(__le16), 1488 &data.pdu); 1489} 1490 1491static void l2cap_le_start(struct l2cap_chan *chan) 1492{ 1493 struct l2cap_conn *conn = chan->conn; 1494 1495 if (!smp_conn_security(conn->hcon, chan->sec_level)) 1496 return; 1497 1498 if (!chan->psm) { 1499 l2cap_chan_ready(chan); 1500 return; 1501 } 1502 1503 if (chan->state == BT_CONNECT) { 1504 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) 1505 l2cap_ecred_connect(chan); 1506 else 1507 l2cap_le_connect(chan); 1508 } 1509} 1510 1511static void l2cap_start_connection(struct l2cap_chan *chan) 1512{ 1513 if (__amp_capable(chan)) { 1514 BT_DBG("chan %p AMP capable: discover AMPs", chan); 1515 a2mp_discover_amp(chan); 1516 } else if (chan->conn->hcon->type == LE_LINK) { 1517 l2cap_le_start(chan); 1518 } else { 1519 l2cap_send_conn_req(chan); 1520 } 1521} 1522 1523static void l2cap_request_info(struct l2cap_conn *conn) 1524{ 1525 struct l2cap_info_req req; 1526 1527 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) 1528 return; 1529 1530 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK); 1531 1532 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT; 1533 conn->info_ident = l2cap_get_ident(conn); 1534 1535 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT); 1536 1537 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ, 1538 sizeof(req), &req); 1539} 1540 1541static bool l2cap_check_enc_key_size(struct hci_conn *hcon) 1542{ 1543 /* The minimum encryption key size needs to be enforced by the 1544 * host stack before establishing any L2CAP connections. The 1545 * specification in theory allows a minimum of 1, but to align 1546 * BR/EDR and LE transports, a minimum of 7 is chosen. 1547 * 1548 * This check might also be called for unencrypted connections 1549 * that have no key size requirements. Ensure that the link is 1550 * actually encrypted before enforcing a key size. 1551 */ 1552 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) || 1553 hcon->enc_key_size >= hcon->hdev->min_enc_key_size); 1554} 1555 1556static void l2cap_do_start(struct l2cap_chan *chan) 1557{ 1558 struct l2cap_conn *conn = chan->conn; 1559 1560 if (conn->hcon->type == LE_LINK) { 1561 l2cap_le_start(chan); 1562 return; 1563 } 1564 1565 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) { 1566 l2cap_request_info(conn); 1567 return; 1568 } 1569 1570 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)) 1571 return; 1572 1573 if (!l2cap_chan_check_security(chan, true) || 1574 !__l2cap_no_conn_pending(chan)) 1575 return; 1576 1577 if (l2cap_check_enc_key_size(conn->hcon)) 1578 l2cap_start_connection(chan); 1579 else 1580 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); 1581} 1582 1583static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask) 1584{ 1585 u32 local_feat_mask = l2cap_feat_mask; 1586 if (!disable_ertm) 1587 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING; 1588 1589 switch (mode) { 1590 case L2CAP_MODE_ERTM: 1591 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask; 1592 case L2CAP_MODE_STREAMING: 1593 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask; 1594 default: 1595 return 0x00; 1596 } 1597} 1598 1599static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err) 1600{ 1601 struct l2cap_conn *conn = chan->conn; 1602 struct l2cap_disconn_req req; 1603 1604 if (!conn) 1605 return; 1606 1607 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) { 1608 __clear_retrans_timer(chan); 1609 __clear_monitor_timer(chan); 1610 __clear_ack_timer(chan); 1611 } 1612 1613 if (chan->scid == L2CAP_CID_A2MP) { 1614 l2cap_state_change(chan, BT_DISCONN); 1615 return; 1616 } 1617 1618 req.dcid = cpu_to_le16(chan->dcid); 1619 req.scid = cpu_to_le16(chan->scid); 1620 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ, 1621 sizeof(req), &req); 1622 1623 l2cap_state_change_and_error(chan, BT_DISCONN, err); 1624} 1625 1626/* ---- L2CAP connections ---- */ 1627static void l2cap_conn_start(struct l2cap_conn *conn) 1628{ 1629 struct l2cap_chan *chan, *tmp; 1630 1631 BT_DBG("conn %p", conn); 1632 1633 mutex_lock(&conn->chan_lock); 1634 1635 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { 1636 l2cap_chan_lock(chan); 1637 1638 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 1639 l2cap_chan_ready(chan); 1640 l2cap_chan_unlock(chan); 1641 continue; 1642 } 1643 1644 if (chan->state == BT_CONNECT) { 1645 if (!l2cap_chan_check_security(chan, true) || 1646 !__l2cap_no_conn_pending(chan)) { 1647 l2cap_chan_unlock(chan); 1648 continue; 1649 } 1650 1651 if (!l2cap_mode_supported(chan->mode, conn->feat_mask) 1652 && test_bit(CONF_STATE2_DEVICE, 1653 &chan->conf_state)) { 1654 l2cap_chan_close(chan, ECONNRESET); 1655 l2cap_chan_unlock(chan); 1656 continue; 1657 } 1658 1659 if (l2cap_check_enc_key_size(conn->hcon)) 1660 l2cap_start_connection(chan); 1661 else 1662 l2cap_chan_close(chan, ECONNREFUSED); 1663 1664 } else if (chan->state == BT_CONNECT2) { 1665 struct l2cap_conn_rsp rsp; 1666 char buf[128]; 1667 rsp.scid = cpu_to_le16(chan->dcid); 1668 rsp.dcid = cpu_to_le16(chan->scid); 1669 1670 if (l2cap_chan_check_security(chan, false)) { 1671 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 1672 rsp.result = cpu_to_le16(L2CAP_CR_PEND); 1673 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND); 1674 chan->ops->defer(chan); 1675 1676 } else { 1677 l2cap_state_change(chan, BT_CONFIG); 1678 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS); 1679 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 1680 } 1681 } else { 1682 rsp.result = cpu_to_le16(L2CAP_CR_PEND); 1683 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND); 1684 } 1685 1686 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, 1687 sizeof(rsp), &rsp); 1688 1689 if (test_bit(CONF_REQ_SENT, &chan->conf_state) || 1690 rsp.result != L2CAP_CR_SUCCESS) { 1691 l2cap_chan_unlock(chan); 1692 continue; 1693 } 1694 1695 set_bit(CONF_REQ_SENT, &chan->conf_state); 1696 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 1697 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 1698 chan->num_conf_req++; 1699 } 1700 1701 l2cap_chan_unlock(chan); 1702 } 1703 1704 mutex_unlock(&conn->chan_lock); 1705} 1706 1707static void l2cap_le_conn_ready(struct l2cap_conn *conn) 1708{ 1709 struct hci_conn *hcon = conn->hcon; 1710 struct hci_dev *hdev = hcon->hdev; 1711 1712 BT_DBG("%s conn %p", hdev->name, conn); 1713 1714 /* For outgoing pairing which doesn't necessarily have an 1715 * associated socket (e.g. mgmt_pair_device). 1716 */ 1717 if (hcon->out) 1718 smp_conn_security(hcon, hcon->pending_sec_level); 1719 1720 /* For LE peripheral connections, make sure the connection interval 1721 * is in the range of the minimum and maximum interval that has 1722 * been configured for this connection. If not, then trigger 1723 * the connection update procedure. 1724 */ 1725 if (hcon->role == HCI_ROLE_SLAVE && 1726 (hcon->le_conn_interval < hcon->le_conn_min_interval || 1727 hcon->le_conn_interval > hcon->le_conn_max_interval)) { 1728 struct l2cap_conn_param_update_req req; 1729 1730 req.min = cpu_to_le16(hcon->le_conn_min_interval); 1731 req.max = cpu_to_le16(hcon->le_conn_max_interval); 1732 req.latency = cpu_to_le16(hcon->le_conn_latency); 1733 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout); 1734 1735 l2cap_send_cmd(conn, l2cap_get_ident(conn), 1736 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req); 1737 } 1738} 1739 1740static void l2cap_conn_ready(struct l2cap_conn *conn) 1741{ 1742 struct l2cap_chan *chan; 1743 struct hci_conn *hcon = conn->hcon; 1744 1745 BT_DBG("conn %p", conn); 1746 1747 if (hcon->type == ACL_LINK) 1748 l2cap_request_info(conn); 1749 1750 mutex_lock(&conn->chan_lock); 1751 1752 list_for_each_entry(chan, &conn->chan_l, list) { 1753 1754 l2cap_chan_lock(chan); 1755 1756 if (chan->scid == L2CAP_CID_A2MP) { 1757 l2cap_chan_unlock(chan); 1758 continue; 1759 } 1760 1761 if (hcon->type == LE_LINK) { 1762 l2cap_le_start(chan); 1763 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 1764 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) 1765 l2cap_chan_ready(chan); 1766 } else if (chan->state == BT_CONNECT) { 1767 l2cap_do_start(chan); 1768 } 1769 1770 l2cap_chan_unlock(chan); 1771 } 1772 1773 mutex_unlock(&conn->chan_lock); 1774 1775 if (hcon->type == LE_LINK) 1776 l2cap_le_conn_ready(conn); 1777 1778 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work); 1779} 1780 1781/* Notify sockets that we cannot guaranty reliability anymore */ 1782static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err) 1783{ 1784 struct l2cap_chan *chan; 1785 1786 BT_DBG("conn %p", conn); 1787 1788 mutex_lock(&conn->chan_lock); 1789 1790 list_for_each_entry(chan, &conn->chan_l, list) { 1791 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags)) 1792 l2cap_chan_set_err(chan, err); 1793 } 1794 1795 mutex_unlock(&conn->chan_lock); 1796} 1797 1798static void l2cap_info_timeout(struct work_struct *work) 1799{ 1800 struct l2cap_conn *conn = container_of(work, struct l2cap_conn, 1801 info_timer.work); 1802 1803 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 1804 conn->info_ident = 0; 1805 1806 l2cap_conn_start(conn); 1807} 1808 1809/* 1810 * l2cap_user 1811 * External modules can register l2cap_user objects on l2cap_conn. The ->probe 1812 * callback is called during registration. The ->remove callback is called 1813 * during unregistration. 1814 * An l2cap_user object can either be explicitly unregistered or when the 1815 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon, 1816 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called. 1817 * External modules must own a reference to the l2cap_conn object if they intend 1818 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at 1819 * any time if they don't. 1820 */ 1821 1822int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user) 1823{ 1824 struct hci_dev *hdev = conn->hcon->hdev; 1825 int ret; 1826 1827 /* We need to check whether l2cap_conn is registered. If it is not, we 1828 * must not register the l2cap_user. l2cap_conn_del() is unregisters 1829 * l2cap_conn objects, but doesn't provide its own locking. Instead, it 1830 * relies on the parent hci_conn object to be locked. This itself relies 1831 * on the hci_dev object to be locked. So we must lock the hci device 1832 * here, too. */ 1833 1834 hci_dev_lock(hdev); 1835 1836 if (!list_empty(&user->list)) { 1837 ret = -EINVAL; 1838 goto out_unlock; 1839 } 1840 1841 /* conn->hchan is NULL after l2cap_conn_del() was called */ 1842 if (!conn->hchan) { 1843 ret = -ENODEV; 1844 goto out_unlock; 1845 } 1846 1847 ret = user->probe(conn, user); 1848 if (ret) 1849 goto out_unlock; 1850 1851 list_add(&user->list, &conn->users); 1852 ret = 0; 1853 1854out_unlock: 1855 hci_dev_unlock(hdev); 1856 return ret; 1857} 1858EXPORT_SYMBOL(l2cap_register_user); 1859 1860void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user) 1861{ 1862 struct hci_dev *hdev = conn->hcon->hdev; 1863 1864 hci_dev_lock(hdev); 1865 1866 if (list_empty(&user->list)) 1867 goto out_unlock; 1868 1869 list_del_init(&user->list); 1870 user->remove(conn, user); 1871 1872out_unlock: 1873 hci_dev_unlock(hdev); 1874} 1875EXPORT_SYMBOL(l2cap_unregister_user); 1876 1877static void l2cap_unregister_all_users(struct l2cap_conn *conn) 1878{ 1879 struct l2cap_user *user; 1880 1881 while (!list_empty(&conn->users)) { 1882 user = list_first_entry(&conn->users, struct l2cap_user, list); 1883 list_del_init(&user->list); 1884 user->remove(conn, user); 1885 } 1886} 1887 1888static void l2cap_conn_del(struct hci_conn *hcon, int err) 1889{ 1890 struct l2cap_conn *conn = hcon->l2cap_data; 1891 struct l2cap_chan *chan, *l; 1892 1893 if (!conn) 1894 return; 1895 1896 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err); 1897 1898 kfree_skb(conn->rx_skb); 1899 1900 skb_queue_purge(&conn->pending_rx); 1901 1902 /* We can not call flush_work(&conn->pending_rx_work) here since we 1903 * might block if we are running on a worker from the same workqueue 1904 * pending_rx_work is waiting on. 1905 */ 1906 if (work_pending(&conn->pending_rx_work)) 1907 cancel_work_sync(&conn->pending_rx_work); 1908 1909 if (work_pending(&conn->id_addr_update_work)) 1910 cancel_work_sync(&conn->id_addr_update_work); 1911 1912 l2cap_unregister_all_users(conn); 1913 1914 /* Force the connection to be immediately dropped */ 1915 hcon->disc_timeout = 0; 1916 1917 mutex_lock(&conn->chan_lock); 1918 1919 /* Kill channels */ 1920 list_for_each_entry_safe(chan, l, &conn->chan_l, list) { 1921 l2cap_chan_hold(chan); 1922 l2cap_chan_lock(chan); 1923 1924 l2cap_chan_del(chan, err); 1925 1926 chan->ops->close(chan); 1927 1928 l2cap_chan_unlock(chan); 1929 l2cap_chan_put(chan); 1930 } 1931 1932 mutex_unlock(&conn->chan_lock); 1933 1934 hci_chan_del(conn->hchan); 1935 1936 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) 1937 cancel_delayed_work_sync(&conn->info_timer); 1938 1939 hcon->l2cap_data = NULL; 1940 conn->hchan = NULL; 1941 l2cap_conn_put(conn); 1942} 1943 1944static void l2cap_conn_free(struct kref *ref) 1945{ 1946 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref); 1947 1948 hci_conn_put(conn->hcon); 1949 kfree(conn); 1950} 1951 1952struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn) 1953{ 1954 kref_get(&conn->ref); 1955 return conn; 1956} 1957EXPORT_SYMBOL(l2cap_conn_get); 1958 1959void l2cap_conn_put(struct l2cap_conn *conn) 1960{ 1961 kref_put(&conn->ref, l2cap_conn_free); 1962} 1963EXPORT_SYMBOL(l2cap_conn_put); 1964 1965/* ---- Socket interface ---- */ 1966 1967/* Find socket with psm and source / destination bdaddr. 1968 * Returns closest match. 1969 */ 1970static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, 1971 bdaddr_t *src, 1972 bdaddr_t *dst, 1973 u8 link_type) 1974{ 1975 struct l2cap_chan *c, *tmp, *c1 = NULL; 1976 1977 read_lock(&chan_list_lock); 1978 1979 list_for_each_entry_safe(c, tmp, &chan_list, global_l) { 1980 if (state && c->state != state) 1981 continue; 1982 1983 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR) 1984 continue; 1985 1986 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR) 1987 continue; 1988 1989 if (c->chan_type != L2CAP_CHAN_FIXED && c->psm == psm) { 1990 int src_match, dst_match; 1991 int src_any, dst_any; 1992 1993 /* Exact match. */ 1994 src_match = !bacmp(&c->src, src); 1995 dst_match = !bacmp(&c->dst, dst); 1996 if (src_match && dst_match) { 1997 if (!l2cap_chan_hold_unless_zero(c)) 1998 continue; 1999 2000 read_unlock(&chan_list_lock); 2001 return c; 2002 } 2003 2004 /* Closest match */ 2005 src_any = !bacmp(&c->src, BDADDR_ANY); 2006 dst_any = !bacmp(&c->dst, BDADDR_ANY); 2007 if ((src_match && dst_any) || (src_any && dst_match) || 2008 (src_any && dst_any)) 2009 c1 = c; 2010 } 2011 } 2012 2013 if (c1) 2014 c1 = l2cap_chan_hold_unless_zero(c1); 2015 2016 read_unlock(&chan_list_lock); 2017 2018 return c1; 2019} 2020 2021static void l2cap_monitor_timeout(struct work_struct *work) 2022{ 2023 struct l2cap_chan *chan = container_of(work, struct l2cap_chan, 2024 monitor_timer.work); 2025 2026 BT_DBG("chan %p", chan); 2027 2028 l2cap_chan_lock(chan); 2029 2030 if (!chan->conn) { 2031 l2cap_chan_unlock(chan); 2032 l2cap_chan_put(chan); 2033 return; 2034 } 2035 2036 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO); 2037 2038 l2cap_chan_unlock(chan); 2039 l2cap_chan_put(chan); 2040} 2041 2042static void l2cap_retrans_timeout(struct work_struct *work) 2043{ 2044 struct l2cap_chan *chan = container_of(work, struct l2cap_chan, 2045 retrans_timer.work); 2046 2047 BT_DBG("chan %p", chan); 2048 2049 l2cap_chan_lock(chan); 2050 2051 if (!chan->conn) { 2052 l2cap_chan_unlock(chan); 2053 l2cap_chan_put(chan); 2054 return; 2055 } 2056 2057 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO); 2058 l2cap_chan_unlock(chan); 2059 l2cap_chan_put(chan); 2060} 2061 2062static void l2cap_streaming_send(struct l2cap_chan *chan, 2063 struct sk_buff_head *skbs) 2064{ 2065 struct sk_buff *skb; 2066 struct l2cap_ctrl *control; 2067 2068 BT_DBG("chan %p, skbs %p", chan, skbs); 2069 2070 if (__chan_is_moving(chan)) 2071 return; 2072 2073 skb_queue_splice_tail_init(skbs, &chan->tx_q); 2074 2075 while (!skb_queue_empty(&chan->tx_q)) { 2076 2077 skb = skb_dequeue(&chan->tx_q); 2078 2079 bt_cb(skb)->l2cap.retries = 1; 2080 control = &bt_cb(skb)->l2cap; 2081 2082 control->reqseq = 0; 2083 control->txseq = chan->next_tx_seq; 2084 2085 __pack_control(chan, control, skb); 2086 2087 if (chan->fcs == L2CAP_FCS_CRC16) { 2088 u16 fcs = crc16(0, (u8 *) skb->data, skb->len); 2089 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE)); 2090 } 2091 2092 l2cap_do_send(chan, skb); 2093 2094 BT_DBG("Sent txseq %u", control->txseq); 2095 2096 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq); 2097 chan->frames_sent++; 2098 } 2099} 2100 2101static int l2cap_ertm_send(struct l2cap_chan *chan) 2102{ 2103 struct sk_buff *skb, *tx_skb; 2104 struct l2cap_ctrl *control; 2105 int sent = 0; 2106 2107 BT_DBG("chan %p", chan); 2108 2109 if (chan->state != BT_CONNECTED) 2110 return -ENOTCONN; 2111 2112 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) 2113 return 0; 2114 2115 if (__chan_is_moving(chan)) 2116 return 0; 2117 2118 while (chan->tx_send_head && 2119 chan->unacked_frames < chan->remote_tx_win && 2120 chan->tx_state == L2CAP_TX_STATE_XMIT) { 2121 2122 skb = chan->tx_send_head; 2123 2124 bt_cb(skb)->l2cap.retries = 1; 2125 control = &bt_cb(skb)->l2cap; 2126 2127 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state)) 2128 control->final = 1; 2129 2130 control->reqseq = chan->buffer_seq; 2131 chan->last_acked_seq = chan->buffer_seq; 2132 control->txseq = chan->next_tx_seq; 2133 2134 __pack_control(chan, control, skb); 2135 2136 if (chan->fcs == L2CAP_FCS_CRC16) { 2137 u16 fcs = crc16(0, (u8 *) skb->data, skb->len); 2138 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE)); 2139 } 2140 2141 /* Clone after data has been modified. Data is assumed to be 2142 read-only (for locking purposes) on cloned sk_buffs. 2143 */ 2144 tx_skb = skb_clone(skb, GFP_KERNEL); 2145 2146 if (!tx_skb) 2147 break; 2148 2149 __set_retrans_timer(chan); 2150 2151 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq); 2152 chan->unacked_frames++; 2153 chan->frames_sent++; 2154 sent++; 2155 2156 if (skb_queue_is_last(&chan->tx_q, skb)) 2157 chan->tx_send_head = NULL; 2158 else 2159 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb); 2160 2161 l2cap_do_send(chan, tx_skb); 2162 BT_DBG("Sent txseq %u", control->txseq); 2163 } 2164 2165 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent, 2166 chan->unacked_frames, skb_queue_len(&chan->tx_q)); 2167 2168 return sent; 2169} 2170 2171static void l2cap_ertm_resend(struct l2cap_chan *chan) 2172{ 2173 struct l2cap_ctrl control; 2174 struct sk_buff *skb; 2175 struct sk_buff *tx_skb; 2176 u16 seq; 2177 2178 BT_DBG("chan %p", chan); 2179 2180 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) 2181 return; 2182 2183 if (__chan_is_moving(chan)) 2184 return; 2185 2186 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) { 2187 seq = l2cap_seq_list_pop(&chan->retrans_list); 2188 2189 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq); 2190 if (!skb) { 2191 BT_DBG("Error: Can't retransmit seq %d, frame missing", 2192 seq); 2193 continue; 2194 } 2195 2196 bt_cb(skb)->l2cap.retries++; 2197 control = bt_cb(skb)->l2cap; 2198 2199 if (chan->max_tx != 0 && 2200 bt_cb(skb)->l2cap.retries > chan->max_tx) { 2201 BT_DBG("Retry limit exceeded (%d)", chan->max_tx); 2202 l2cap_send_disconn_req(chan, ECONNRESET); 2203 l2cap_seq_list_clear(&chan->retrans_list); 2204 break; 2205 } 2206 2207 control.reqseq = chan->buffer_seq; 2208 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state)) 2209 control.final = 1; 2210 else 2211 control.final = 0; 2212 2213 if (skb_cloned(skb)) { 2214 /* Cloned sk_buffs are read-only, so we need a 2215 * writeable copy 2216 */ 2217 tx_skb = skb_copy(skb, GFP_KERNEL); 2218 } else { 2219 tx_skb = skb_clone(skb, GFP_KERNEL); 2220 } 2221 2222 if (!tx_skb) { 2223 l2cap_seq_list_clear(&chan->retrans_list); 2224 break; 2225 } 2226 2227 /* Update skb contents */ 2228 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) { 2229 put_unaligned_le32(__pack_extended_control(&control), 2230 tx_skb->data + L2CAP_HDR_SIZE); 2231 } else { 2232 put_unaligned_le16(__pack_enhanced_control(&control), 2233 tx_skb->data + L2CAP_HDR_SIZE); 2234 } 2235 2236 /* Update FCS */ 2237 if (chan->fcs == L2CAP_FCS_CRC16) { 2238 u16 fcs = crc16(0, (u8 *) tx_skb->data, 2239 tx_skb->len - L2CAP_FCS_SIZE); 2240 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) - 2241 L2CAP_FCS_SIZE); 2242 } 2243 2244 l2cap_do_send(chan, tx_skb); 2245 2246 BT_DBG("Resent txseq %d", control.txseq); 2247 2248 chan->last_acked_seq = chan->buffer_seq; 2249 } 2250} 2251 2252static void l2cap_retransmit(struct l2cap_chan *chan, 2253 struct l2cap_ctrl *control) 2254{ 2255 BT_DBG("chan %p, control %p", chan, control); 2256 2257 l2cap_seq_list_append(&chan->retrans_list, control->reqseq); 2258 l2cap_ertm_resend(chan); 2259} 2260 2261static void l2cap_retransmit_all(struct l2cap_chan *chan, 2262 struct l2cap_ctrl *control) 2263{ 2264 struct sk_buff *skb; 2265 2266 BT_DBG("chan %p, control %p", chan, control); 2267 2268 if (control->poll) 2269 set_bit(CONN_SEND_FBIT, &chan->conn_state); 2270 2271 l2cap_seq_list_clear(&chan->retrans_list); 2272 2273 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) 2274 return; 2275 2276 if (chan->unacked_frames) { 2277 skb_queue_walk(&chan->tx_q, skb) { 2278 if (bt_cb(skb)->l2cap.txseq == control->reqseq || 2279 skb == chan->tx_send_head) 2280 break; 2281 } 2282 2283 skb_queue_walk_from(&chan->tx_q, skb) { 2284 if (skb == chan->tx_send_head) 2285 break; 2286 2287 l2cap_seq_list_append(&chan->retrans_list, 2288 bt_cb(skb)->l2cap.txseq); 2289 } 2290 2291 l2cap_ertm_resend(chan); 2292 } 2293} 2294 2295static void l2cap_send_ack(struct l2cap_chan *chan) 2296{ 2297 struct l2cap_ctrl control; 2298 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq, 2299 chan->last_acked_seq); 2300 int threshold; 2301 2302 BT_DBG("chan %p last_acked_seq %d buffer_seq %d", 2303 chan, chan->last_acked_seq, chan->buffer_seq); 2304 2305 memset(&control, 0, sizeof(control)); 2306 control.sframe = 1; 2307 2308 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) && 2309 chan->rx_state == L2CAP_RX_STATE_RECV) { 2310 __clear_ack_timer(chan); 2311 control.super = L2CAP_SUPER_RNR; 2312 control.reqseq = chan->buffer_seq; 2313 l2cap_send_sframe(chan, &control); 2314 } else { 2315 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) { 2316 l2cap_ertm_send(chan); 2317 /* If any i-frames were sent, they included an ack */ 2318 if (chan->buffer_seq == chan->last_acked_seq) 2319 frames_to_ack = 0; 2320 } 2321 2322 /* Ack now if the window is 3/4ths full. 2323 * Calculate without mul or div 2324 */ 2325 threshold = chan->ack_win; 2326 threshold += threshold << 1; 2327 threshold >>= 2; 2328 2329 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack, 2330 threshold); 2331 2332 if (frames_to_ack >= threshold) { 2333 __clear_ack_timer(chan); 2334 control.super = L2CAP_SUPER_RR; 2335 control.reqseq = chan->buffer_seq; 2336 l2cap_send_sframe(chan, &control); 2337 frames_to_ack = 0; 2338 } 2339 2340 if (frames_to_ack) 2341 __set_ack_timer(chan); 2342 } 2343} 2344 2345static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan, 2346 struct msghdr *msg, int len, 2347 int count, struct sk_buff *skb) 2348{ 2349 struct l2cap_conn *conn = chan->conn; 2350 struct sk_buff **frag; 2351 int sent = 0; 2352 2353 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter)) 2354 return -EFAULT; 2355 2356 sent += count; 2357 len -= count; 2358 2359 /* Continuation fragments (no L2CAP header) */ 2360 frag = &skb_shinfo(skb)->frag_list; 2361 while (len) { 2362 struct sk_buff *tmp; 2363 2364 count = min_t(unsigned int, conn->mtu, len); 2365 2366 tmp = chan->ops->alloc_skb(chan, 0, count, 2367 msg->msg_flags & MSG_DONTWAIT); 2368 if (IS_ERR(tmp)) 2369 return PTR_ERR(tmp); 2370 2371 *frag = tmp; 2372 2373 if (!copy_from_iter_full(skb_put(*frag, count), count, 2374 &msg->msg_iter)) 2375 return -EFAULT; 2376 2377 sent += count; 2378 len -= count; 2379 2380 skb->len += (*frag)->len; 2381 skb->data_len += (*frag)->len; 2382 2383 frag = &(*frag)->next; 2384 } 2385 2386 return sent; 2387} 2388 2389static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan, 2390 struct msghdr *msg, size_t len) 2391{ 2392 struct l2cap_conn *conn = chan->conn; 2393 struct sk_buff *skb; 2394 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE; 2395 struct l2cap_hdr *lh; 2396 2397 BT_DBG("chan %p psm 0x%2.2x len %zu", chan, 2398 __le16_to_cpu(chan->psm), len); 2399 2400 count = min_t(unsigned int, (conn->mtu - hlen), len); 2401 2402 skb = chan->ops->alloc_skb(chan, hlen, count, 2403 msg->msg_flags & MSG_DONTWAIT); 2404 if (IS_ERR(skb)) 2405 return skb; 2406 2407 /* Create L2CAP header */ 2408 lh = skb_put(skb, L2CAP_HDR_SIZE); 2409 lh->cid = cpu_to_le16(chan->dcid); 2410 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE); 2411 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE)); 2412 2413 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb); 2414 if (unlikely(err < 0)) { 2415 kfree_skb(skb); 2416 return ERR_PTR(err); 2417 } 2418 return skb; 2419} 2420 2421static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan, 2422 struct msghdr *msg, size_t len) 2423{ 2424 struct l2cap_conn *conn = chan->conn; 2425 struct sk_buff *skb; 2426 int err, count; 2427 struct l2cap_hdr *lh; 2428 2429 BT_DBG("chan %p len %zu", chan, len); 2430 2431 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len); 2432 2433 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count, 2434 msg->msg_flags & MSG_DONTWAIT); 2435 if (IS_ERR(skb)) 2436 return skb; 2437 2438 /* Create L2CAP header */ 2439 lh = skb_put(skb, L2CAP_HDR_SIZE); 2440 lh->cid = cpu_to_le16(chan->dcid); 2441 lh->len = cpu_to_le16(len); 2442 2443 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb); 2444 if (unlikely(err < 0)) { 2445 kfree_skb(skb); 2446 return ERR_PTR(err); 2447 } 2448 return skb; 2449} 2450 2451static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan, 2452 struct msghdr *msg, size_t len, 2453 u16 sdulen) 2454{ 2455 struct l2cap_conn *conn = chan->conn; 2456 struct sk_buff *skb; 2457 int err, count, hlen; 2458 struct l2cap_hdr *lh; 2459 2460 BT_DBG("chan %p len %zu", chan, len); 2461 2462 if (!conn) 2463 return ERR_PTR(-ENOTCONN); 2464 2465 hlen = __ertm_hdr_size(chan); 2466 2467 if (sdulen) 2468 hlen += L2CAP_SDULEN_SIZE; 2469 2470 if (chan->fcs == L2CAP_FCS_CRC16) 2471 hlen += L2CAP_FCS_SIZE; 2472 2473 count = min_t(unsigned int, (conn->mtu - hlen), len); 2474 2475 skb = chan->ops->alloc_skb(chan, hlen, count, 2476 msg->msg_flags & MSG_DONTWAIT); 2477 if (IS_ERR(skb)) 2478 return skb; 2479 2480 /* Create L2CAP header */ 2481 lh = skb_put(skb, L2CAP_HDR_SIZE); 2482 lh->cid = cpu_to_le16(chan->dcid); 2483 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE)); 2484 2485 /* Control header is populated later */ 2486 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 2487 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE)); 2488 else 2489 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE)); 2490 2491 if (sdulen) 2492 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE)); 2493 2494 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb); 2495 if (unlikely(err < 0)) { 2496 kfree_skb(skb); 2497 return ERR_PTR(err); 2498 } 2499 2500 bt_cb(skb)->l2cap.fcs = chan->fcs; 2501 bt_cb(skb)->l2cap.retries = 0; 2502 return skb; 2503} 2504 2505static int l2cap_segment_sdu(struct l2cap_chan *chan, 2506 struct sk_buff_head *seg_queue, 2507 struct msghdr *msg, size_t len) 2508{ 2509 struct sk_buff *skb; 2510 u16 sdu_len; 2511 size_t pdu_len; 2512 u8 sar; 2513 2514 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len); 2515 2516 /* It is critical that ERTM PDUs fit in a single HCI fragment, 2517 * so fragmented skbs are not used. The HCI layer's handling 2518 * of fragmented skbs is not compatible with ERTM's queueing. 2519 */ 2520 2521 /* PDU size is derived from the HCI MTU */ 2522 pdu_len = chan->conn->mtu; 2523 2524 /* Constrain PDU size for BR/EDR connections */ 2525 if (!chan->hs_hcon) 2526 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD); 2527 2528 /* Adjust for largest possible L2CAP overhead. */ 2529 if (chan->fcs) 2530 pdu_len -= L2CAP_FCS_SIZE; 2531 2532 pdu_len -= __ertm_hdr_size(chan); 2533 2534 /* Remote device may have requested smaller PDUs */ 2535 pdu_len = min_t(size_t, pdu_len, chan->remote_mps); 2536 2537 if (len <= pdu_len) { 2538 sar = L2CAP_SAR_UNSEGMENTED; 2539 sdu_len = 0; 2540 pdu_len = len; 2541 } else { 2542 sar = L2CAP_SAR_START; 2543 sdu_len = len; 2544 } 2545 2546 while (len > 0) { 2547 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len); 2548 2549 if (IS_ERR(skb)) { 2550 __skb_queue_purge(seg_queue); 2551 return PTR_ERR(skb); 2552 } 2553 2554 bt_cb(skb)->l2cap.sar = sar; 2555 __skb_queue_tail(seg_queue, skb); 2556 2557 len -= pdu_len; 2558 if (sdu_len) 2559 sdu_len = 0; 2560 2561 if (len <= pdu_len) { 2562 sar = L2CAP_SAR_END; 2563 pdu_len = len; 2564 } else { 2565 sar = L2CAP_SAR_CONTINUE; 2566 } 2567 } 2568 2569 return 0; 2570} 2571 2572static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan, 2573 struct msghdr *msg, 2574 size_t len, u16 sdulen) 2575{ 2576 struct l2cap_conn *conn = chan->conn; 2577 struct sk_buff *skb; 2578 int err, count, hlen; 2579 struct l2cap_hdr *lh; 2580 2581 BT_DBG("chan %p len %zu", chan, len); 2582 2583 if (!conn) 2584 return ERR_PTR(-ENOTCONN); 2585 2586 hlen = L2CAP_HDR_SIZE; 2587 2588 if (sdulen) 2589 hlen += L2CAP_SDULEN_SIZE; 2590 2591 count = min_t(unsigned int, (conn->mtu - hlen), len); 2592 2593 skb = chan->ops->alloc_skb(chan, hlen, count, 2594 msg->msg_flags & MSG_DONTWAIT); 2595 if (IS_ERR(skb)) 2596 return skb; 2597 2598 /* Create L2CAP header */ 2599 lh = skb_put(skb, L2CAP_HDR_SIZE); 2600 lh->cid = cpu_to_le16(chan->dcid); 2601 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE)); 2602 2603 if (sdulen) 2604 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE)); 2605 2606 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb); 2607 if (unlikely(err < 0)) { 2608 kfree_skb(skb); 2609 return ERR_PTR(err); 2610 } 2611 2612 return skb; 2613} 2614 2615static int l2cap_segment_le_sdu(struct l2cap_chan *chan, 2616 struct sk_buff_head *seg_queue, 2617 struct msghdr *msg, size_t len) 2618{ 2619 struct sk_buff *skb; 2620 size_t pdu_len; 2621 u16 sdu_len; 2622 2623 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len); 2624 2625 sdu_len = len; 2626 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE; 2627 2628 while (len > 0) { 2629 if (len <= pdu_len) 2630 pdu_len = len; 2631 2632 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len); 2633 if (IS_ERR(skb)) { 2634 __skb_queue_purge(seg_queue); 2635 return PTR_ERR(skb); 2636 } 2637 2638 __skb_queue_tail(seg_queue, skb); 2639 2640 len -= pdu_len; 2641 2642 if (sdu_len) { 2643 sdu_len = 0; 2644 pdu_len += L2CAP_SDULEN_SIZE; 2645 } 2646 } 2647 2648 return 0; 2649} 2650 2651static void l2cap_le_flowctl_send(struct l2cap_chan *chan) 2652{ 2653 int sent = 0; 2654 2655 BT_DBG("chan %p", chan); 2656 2657 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) { 2658 l2cap_do_send(chan, skb_dequeue(&chan->tx_q)); 2659 chan->tx_credits--; 2660 sent++; 2661 } 2662 2663 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits, 2664 skb_queue_len(&chan->tx_q)); 2665} 2666 2667int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len) 2668{ 2669 struct sk_buff *skb; 2670 int err; 2671 struct sk_buff_head seg_queue; 2672 2673 if (!chan->conn) 2674 return -ENOTCONN; 2675 2676 /* Connectionless channel */ 2677 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) { 2678 skb = l2cap_create_connless_pdu(chan, msg, len); 2679 if (IS_ERR(skb)) 2680 return PTR_ERR(skb); 2681 2682 l2cap_do_send(chan, skb); 2683 return len; 2684 } 2685 2686 switch (chan->mode) { 2687 case L2CAP_MODE_LE_FLOWCTL: 2688 case L2CAP_MODE_EXT_FLOWCTL: 2689 /* Check outgoing MTU */ 2690 if (len > chan->omtu) 2691 return -EMSGSIZE; 2692 2693 __skb_queue_head_init(&seg_queue); 2694 2695 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len); 2696 2697 if (chan->state != BT_CONNECTED) { 2698 __skb_queue_purge(&seg_queue); 2699 err = -ENOTCONN; 2700 } 2701 2702 if (err) 2703 return err; 2704 2705 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q); 2706 2707 l2cap_le_flowctl_send(chan); 2708 2709 if (!chan->tx_credits) 2710 chan->ops->suspend(chan); 2711 2712 err = len; 2713 2714 break; 2715 2716 case L2CAP_MODE_BASIC: 2717 /* Check outgoing MTU */ 2718 if (len > chan->omtu) 2719 return -EMSGSIZE; 2720 2721 /* Create a basic PDU */ 2722 skb = l2cap_create_basic_pdu(chan, msg, len); 2723 if (IS_ERR(skb)) 2724 return PTR_ERR(skb); 2725 2726 l2cap_do_send(chan, skb); 2727 err = len; 2728 break; 2729 2730 case L2CAP_MODE_ERTM: 2731 case L2CAP_MODE_STREAMING: 2732 /* Check outgoing MTU */ 2733 if (len > chan->omtu) { 2734 err = -EMSGSIZE; 2735 break; 2736 } 2737 2738 __skb_queue_head_init(&seg_queue); 2739 2740 /* Do segmentation before calling in to the state machine, 2741 * since it's possible to block while waiting for memory 2742 * allocation. 2743 */ 2744 err = l2cap_segment_sdu(chan, &seg_queue, msg, len); 2745 2746 if (err) 2747 break; 2748 2749 if (chan->mode == L2CAP_MODE_ERTM) 2750 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST); 2751 else 2752 l2cap_streaming_send(chan, &seg_queue); 2753 2754 err = len; 2755 2756 /* If the skbs were not queued for sending, they'll still be in 2757 * seg_queue and need to be purged. 2758 */ 2759 __skb_queue_purge(&seg_queue); 2760 break; 2761 2762 default: 2763 BT_DBG("bad state %1.1x", chan->mode); 2764 err = -EBADFD; 2765 } 2766 2767 return err; 2768} 2769EXPORT_SYMBOL_GPL(l2cap_chan_send); 2770 2771static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq) 2772{ 2773 struct l2cap_ctrl control; 2774 u16 seq; 2775 2776 BT_DBG("chan %p, txseq %u", chan, txseq); 2777 2778 memset(&control, 0, sizeof(control)); 2779 control.sframe = 1; 2780 control.super = L2CAP_SUPER_SREJ; 2781 2782 for (seq = chan->expected_tx_seq; seq != txseq; 2783 seq = __next_seq(chan, seq)) { 2784 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) { 2785 control.reqseq = seq; 2786 l2cap_send_sframe(chan, &control); 2787 l2cap_seq_list_append(&chan->srej_list, seq); 2788 } 2789 } 2790 2791 chan->expected_tx_seq = __next_seq(chan, txseq); 2792} 2793 2794static void l2cap_send_srej_tail(struct l2cap_chan *chan) 2795{ 2796 struct l2cap_ctrl control; 2797 2798 BT_DBG("chan %p", chan); 2799 2800 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR) 2801 return; 2802 2803 memset(&control, 0, sizeof(control)); 2804 control.sframe = 1; 2805 control.super = L2CAP_SUPER_SREJ; 2806 control.reqseq = chan->srej_list.tail; 2807 l2cap_send_sframe(chan, &control); 2808} 2809 2810static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq) 2811{ 2812 struct l2cap_ctrl control; 2813 u16 initial_head; 2814 u16 seq; 2815 2816 BT_DBG("chan %p, txseq %u", chan, txseq); 2817 2818 memset(&control, 0, sizeof(control)); 2819 control.sframe = 1; 2820 control.super = L2CAP_SUPER_SREJ; 2821 2822 /* Capture initial list head to allow only one pass through the list. */ 2823 initial_head = chan->srej_list.head; 2824 2825 do { 2826 seq = l2cap_seq_list_pop(&chan->srej_list); 2827 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR) 2828 break; 2829 2830 control.reqseq = seq; 2831 l2cap_send_sframe(chan, &control); 2832 l2cap_seq_list_append(&chan->srej_list, seq); 2833 } while (chan->srej_list.head != initial_head); 2834} 2835 2836static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq) 2837{ 2838 struct sk_buff *acked_skb; 2839 u16 ackseq; 2840 2841 BT_DBG("chan %p, reqseq %u", chan, reqseq); 2842 2843 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq) 2844 return; 2845 2846 BT_DBG("expected_ack_seq %u, unacked_frames %u", 2847 chan->expected_ack_seq, chan->unacked_frames); 2848 2849 for (ackseq = chan->expected_ack_seq; ackseq != reqseq; 2850 ackseq = __next_seq(chan, ackseq)) { 2851 2852 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq); 2853 if (acked_skb) { 2854 skb_unlink(acked_skb, &chan->tx_q); 2855 kfree_skb(acked_skb); 2856 chan->unacked_frames--; 2857 } 2858 } 2859 2860 chan->expected_ack_seq = reqseq; 2861 2862 if (chan->unacked_frames == 0) 2863 __clear_retrans_timer(chan); 2864 2865 BT_DBG("unacked_frames %u", chan->unacked_frames); 2866} 2867 2868static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan) 2869{ 2870 BT_DBG("chan %p", chan); 2871 2872 chan->expected_tx_seq = chan->buffer_seq; 2873 l2cap_seq_list_clear(&chan->srej_list); 2874 skb_queue_purge(&chan->srej_q); 2875 chan->rx_state = L2CAP_RX_STATE_RECV; 2876} 2877 2878static void l2cap_tx_state_xmit(struct l2cap_chan *chan, 2879 struct l2cap_ctrl *control, 2880 struct sk_buff_head *skbs, u8 event) 2881{ 2882 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs, 2883 event); 2884 2885 switch (event) { 2886 case L2CAP_EV_DATA_REQUEST: 2887 if (chan->tx_send_head == NULL) 2888 chan->tx_send_head = skb_peek(skbs); 2889 2890 skb_queue_splice_tail_init(skbs, &chan->tx_q); 2891 l2cap_ertm_send(chan); 2892 break; 2893 case L2CAP_EV_LOCAL_BUSY_DETECTED: 2894 BT_DBG("Enter LOCAL_BUSY"); 2895 set_bit(CONN_LOCAL_BUSY, &chan->conn_state); 2896 2897 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) { 2898 /* The SREJ_SENT state must be aborted if we are to 2899 * enter the LOCAL_BUSY state. 2900 */ 2901 l2cap_abort_rx_srej_sent(chan); 2902 } 2903 2904 l2cap_send_ack(chan); 2905 2906 break; 2907 case L2CAP_EV_LOCAL_BUSY_CLEAR: 2908 BT_DBG("Exit LOCAL_BUSY"); 2909 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state); 2910 2911 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) { 2912 struct l2cap_ctrl local_control; 2913 2914 memset(&local_control, 0, sizeof(local_control)); 2915 local_control.sframe = 1; 2916 local_control.super = L2CAP_SUPER_RR; 2917 local_control.poll = 1; 2918 local_control.reqseq = chan->buffer_seq; 2919 l2cap_send_sframe(chan, &local_control); 2920 2921 chan->retry_count = 1; 2922 __set_monitor_timer(chan); 2923 chan->tx_state = L2CAP_TX_STATE_WAIT_F; 2924 } 2925 break; 2926 case L2CAP_EV_RECV_REQSEQ_AND_FBIT: 2927 l2cap_process_reqseq(chan, control->reqseq); 2928 break; 2929 case L2CAP_EV_EXPLICIT_POLL: 2930 l2cap_send_rr_or_rnr(chan, 1); 2931 chan->retry_count = 1; 2932 __set_monitor_timer(chan); 2933 __clear_ack_timer(chan); 2934 chan->tx_state = L2CAP_TX_STATE_WAIT_F; 2935 break; 2936 case L2CAP_EV_RETRANS_TO: 2937 l2cap_send_rr_or_rnr(chan, 1); 2938 chan->retry_count = 1; 2939 __set_monitor_timer(chan); 2940 chan->tx_state = L2CAP_TX_STATE_WAIT_F; 2941 break; 2942 case L2CAP_EV_RECV_FBIT: 2943 /* Nothing to process */ 2944 break; 2945 default: 2946 break; 2947 } 2948} 2949 2950static void l2cap_tx_state_wait_f(struct l2cap_chan *chan, 2951 struct l2cap_ctrl *control, 2952 struct sk_buff_head *skbs, u8 event) 2953{ 2954 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs, 2955 event); 2956 2957 switch (event) { 2958 case L2CAP_EV_DATA_REQUEST: 2959 if (chan->tx_send_head == NULL) 2960 chan->tx_send_head = skb_peek(skbs); 2961 /* Queue data, but don't send. */ 2962 skb_queue_splice_tail_init(skbs, &chan->tx_q); 2963 break; 2964 case L2CAP_EV_LOCAL_BUSY_DETECTED: 2965 BT_DBG("Enter LOCAL_BUSY"); 2966 set_bit(CONN_LOCAL_BUSY, &chan->conn_state); 2967 2968 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) { 2969 /* The SREJ_SENT state must be aborted if we are to 2970 * enter the LOCAL_BUSY state. 2971 */ 2972 l2cap_abort_rx_srej_sent(chan); 2973 } 2974 2975 l2cap_send_ack(chan); 2976 2977 break; 2978 case L2CAP_EV_LOCAL_BUSY_CLEAR: 2979 BT_DBG("Exit LOCAL_BUSY"); 2980 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state); 2981 2982 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) { 2983 struct l2cap_ctrl local_control; 2984 memset(&local_control, 0, sizeof(local_control)); 2985 local_control.sframe = 1; 2986 local_control.super = L2CAP_SUPER_RR; 2987 local_control.poll = 1; 2988 local_control.reqseq = chan->buffer_seq; 2989 l2cap_send_sframe(chan, &local_control); 2990 2991 chan->retry_count = 1; 2992 __set_monitor_timer(chan); 2993 chan->tx_state = L2CAP_TX_STATE_WAIT_F; 2994 } 2995 break; 2996 case L2CAP_EV_RECV_REQSEQ_AND_FBIT: 2997 l2cap_process_reqseq(chan, control->reqseq); 2998 fallthrough; 2999 3000 case L2CAP_EV_RECV_FBIT: 3001 if (control && control->final) { 3002 __clear_monitor_timer(chan); 3003 if (chan->unacked_frames > 0) 3004 __set_retrans_timer(chan); 3005 chan->retry_count = 0; 3006 chan->tx_state = L2CAP_TX_STATE_XMIT; 3007 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state); 3008 } 3009 break; 3010 case L2CAP_EV_EXPLICIT_POLL: 3011 /* Ignore */ 3012 break; 3013 case L2CAP_EV_MONITOR_TO: 3014 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) { 3015 l2cap_send_rr_or_rnr(chan, 1); 3016 __set_monitor_timer(chan); 3017 chan->retry_count++; 3018 } else { 3019 l2cap_send_disconn_req(chan, ECONNABORTED); 3020 } 3021 break; 3022 default: 3023 break; 3024 } 3025} 3026 3027static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control, 3028 struct sk_buff_head *skbs, u8 event) 3029{ 3030 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d", 3031 chan, control, skbs, event, chan->tx_state); 3032 3033 switch (chan->tx_state) { 3034 case L2CAP_TX_STATE_XMIT: 3035 l2cap_tx_state_xmit(chan, control, skbs, event); 3036 break; 3037 case L2CAP_TX_STATE_WAIT_F: 3038 l2cap_tx_state_wait_f(chan, control, skbs, event); 3039 break; 3040 default: 3041 /* Ignore event */ 3042 break; 3043 } 3044} 3045 3046static void l2cap_pass_to_tx(struct l2cap_chan *chan, 3047 struct l2cap_ctrl *control) 3048{ 3049 BT_DBG("chan %p, control %p", chan, control); 3050 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT); 3051} 3052 3053static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan, 3054 struct l2cap_ctrl *control) 3055{ 3056 BT_DBG("chan %p, control %p", chan, control); 3057 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT); 3058} 3059 3060/* Copy frame to all raw sockets on that connection */ 3061static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb) 3062{ 3063 struct sk_buff *nskb; 3064 struct l2cap_chan *chan; 3065 3066 BT_DBG("conn %p", conn); 3067 3068 mutex_lock(&conn->chan_lock); 3069 3070 list_for_each_entry(chan, &conn->chan_l, list) { 3071 if (chan->chan_type != L2CAP_CHAN_RAW) 3072 continue; 3073 3074 /* Don't send frame to the channel it came from */ 3075 if (bt_cb(skb)->l2cap.chan == chan) 3076 continue; 3077 3078 nskb = skb_clone(skb, GFP_KERNEL); 3079 if (!nskb) 3080 continue; 3081 if (chan->ops->recv(chan, nskb)) 3082 kfree_skb(nskb); 3083 } 3084 3085 mutex_unlock(&conn->chan_lock); 3086} 3087 3088/* ---- L2CAP signalling commands ---- */ 3089static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code, 3090 u8 ident, u16 dlen, void *data) 3091{ 3092 struct sk_buff *skb, **frag; 3093 struct l2cap_cmd_hdr *cmd; 3094 struct l2cap_hdr *lh; 3095 int len, count; 3096 3097 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u", 3098 conn, code, ident, dlen); 3099 3100 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE) 3101 return NULL; 3102 3103 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen; 3104 count = min_t(unsigned int, conn->mtu, len); 3105 3106 skb = bt_skb_alloc(count, GFP_KERNEL); 3107 if (!skb) 3108 return NULL; 3109 3110 lh = skb_put(skb, L2CAP_HDR_SIZE); 3111 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen); 3112 3113 if (conn->hcon->type == LE_LINK) 3114 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING); 3115 else 3116 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING); 3117 3118 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE); 3119 cmd->code = code; 3120 cmd->ident = ident; 3121 cmd->len = cpu_to_le16(dlen); 3122 3123 if (dlen) { 3124 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE; 3125 skb_put_data(skb, data, count); 3126 data += count; 3127 } 3128 3129 len -= skb->len; 3130 3131 /* Continuation fragments (no L2CAP header) */ 3132 frag = &skb_shinfo(skb)->frag_list; 3133 while (len) { 3134 count = min_t(unsigned int, conn->mtu, len); 3135 3136 *frag = bt_skb_alloc(count, GFP_KERNEL); 3137 if (!*frag) 3138 goto fail; 3139 3140 skb_put_data(*frag, data, count); 3141 3142 len -= count; 3143 data += count; 3144 3145 frag = &(*frag)->next; 3146 } 3147 3148 return skb; 3149 3150fail: 3151 kfree_skb(skb); 3152 return NULL; 3153} 3154 3155static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen, 3156 unsigned long *val) 3157{ 3158 struct l2cap_conf_opt *opt = *ptr; 3159 int len; 3160 3161 len = L2CAP_CONF_OPT_SIZE + opt->len; 3162 *ptr += len; 3163 3164 *type = opt->type; 3165 *olen = opt->len; 3166 3167 switch (opt->len) { 3168 case 1: 3169 *val = *((u8 *) opt->val); 3170 break; 3171 3172 case 2: 3173 *val = get_unaligned_le16(opt->val); 3174 break; 3175 3176 case 4: 3177 *val = get_unaligned_le32(opt->val); 3178 break; 3179 3180 default: 3181 *val = (unsigned long) opt->val; 3182 break; 3183 } 3184 3185 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val); 3186 return len; 3187} 3188 3189static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size) 3190{ 3191 struct l2cap_conf_opt *opt = *ptr; 3192 3193 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val); 3194 3195 if (size < L2CAP_CONF_OPT_SIZE + len) 3196 return; 3197 3198 opt->type = type; 3199 opt->len = len; 3200 3201 switch (len) { 3202 case 1: 3203 *((u8 *) opt->val) = val; 3204 break; 3205 3206 case 2: 3207 put_unaligned_le16(val, opt->val); 3208 break; 3209 3210 case 4: 3211 put_unaligned_le32(val, opt->val); 3212 break; 3213 3214 default: 3215 memcpy(opt->val, (void *) val, len); 3216 break; 3217 } 3218 3219 *ptr += L2CAP_CONF_OPT_SIZE + len; 3220} 3221 3222static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size) 3223{ 3224 struct l2cap_conf_efs efs; 3225 3226 switch (chan->mode) { 3227 case L2CAP_MODE_ERTM: 3228 efs.id = chan->local_id; 3229 efs.stype = chan->local_stype; 3230 efs.msdu = cpu_to_le16(chan->local_msdu); 3231 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime); 3232 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT); 3233 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO); 3234 break; 3235 3236 case L2CAP_MODE_STREAMING: 3237 efs.id = 1; 3238 efs.stype = L2CAP_SERV_BESTEFFORT; 3239 efs.msdu = cpu_to_le16(chan->local_msdu); 3240 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime); 3241 efs.acc_lat = 0; 3242 efs.flush_to = 0; 3243 break; 3244 3245 default: 3246 return; 3247 } 3248 3249 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs), 3250 (unsigned long) &efs, size); 3251} 3252 3253static void l2cap_ack_timeout(struct work_struct *work) 3254{ 3255 struct l2cap_chan *chan = container_of(work, struct l2cap_chan, 3256 ack_timer.work); 3257 u16 frames_to_ack; 3258 3259 BT_DBG("chan %p", chan); 3260 3261 l2cap_chan_lock(chan); 3262 3263 frames_to_ack = __seq_offset(chan, chan->buffer_seq, 3264 chan->last_acked_seq); 3265 3266 if (frames_to_ack) 3267 l2cap_send_rr_or_rnr(chan, 0); 3268 3269 l2cap_chan_unlock(chan); 3270 l2cap_chan_put(chan); 3271} 3272 3273int l2cap_ertm_init(struct l2cap_chan *chan) 3274{ 3275 int err; 3276 3277 chan->next_tx_seq = 0; 3278 chan->expected_tx_seq = 0; 3279 chan->expected_ack_seq = 0; 3280 chan->unacked_frames = 0; 3281 chan->buffer_seq = 0; 3282 chan->frames_sent = 0; 3283 chan->last_acked_seq = 0; 3284 chan->sdu = NULL; 3285 chan->sdu_last_frag = NULL; 3286 chan->sdu_len = 0; 3287 3288 skb_queue_head_init(&chan->tx_q); 3289 3290 chan->local_amp_id = AMP_ID_BREDR; 3291 chan->move_id = AMP_ID_BREDR; 3292 chan->move_state = L2CAP_MOVE_STABLE; 3293 chan->move_role = L2CAP_MOVE_ROLE_NONE; 3294 3295 if (chan->mode != L2CAP_MODE_ERTM) 3296 return 0; 3297 3298 chan->rx_state = L2CAP_RX_STATE_RECV; 3299 chan->tx_state = L2CAP_TX_STATE_XMIT; 3300 3301 skb_queue_head_init(&chan->srej_q); 3302 3303 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win); 3304 if (err < 0) 3305 return err; 3306 3307 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win); 3308 if (err < 0) 3309 l2cap_seq_list_free(&chan->srej_list); 3310 3311 return err; 3312} 3313 3314static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask) 3315{ 3316 switch (mode) { 3317 case L2CAP_MODE_STREAMING: 3318 case L2CAP_MODE_ERTM: 3319 if (l2cap_mode_supported(mode, remote_feat_mask)) 3320 return mode; 3321 fallthrough; 3322 default: 3323 return L2CAP_MODE_BASIC; 3324 } 3325} 3326 3327static inline bool __l2cap_ews_supported(struct l2cap_conn *conn) 3328{ 3329 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) && 3330 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW)); 3331} 3332 3333static inline bool __l2cap_efs_supported(struct l2cap_conn *conn) 3334{ 3335 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) && 3336 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW)); 3337} 3338 3339static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan, 3340 struct l2cap_conf_rfc *rfc) 3341{ 3342 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) { 3343 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to; 3344 3345 /* Class 1 devices have must have ERTM timeouts 3346 * exceeding the Link Supervision Timeout. The 3347 * default Link Supervision Timeout for AMP 3348 * controllers is 10 seconds. 3349 * 3350 * Class 1 devices use 0xffffffff for their 3351 * best-effort flush timeout, so the clamping logic 3352 * will result in a timeout that meets the above 3353 * requirement. ERTM timeouts are 16-bit values, so 3354 * the maximum timeout is 65.535 seconds. 3355 */ 3356 3357 /* Convert timeout to milliseconds and round */ 3358 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000); 3359 3360 /* This is the recommended formula for class 2 devices 3361 * that start ERTM timers when packets are sent to the 3362 * controller. 3363 */ 3364 ertm_to = 3 * ertm_to + 500; 3365 3366 if (ertm_to > 0xffff) 3367 ertm_to = 0xffff; 3368 3369 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to); 3370 rfc->monitor_timeout = rfc->retrans_timeout; 3371 } else { 3372 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO); 3373 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO); 3374 } 3375} 3376 3377static inline void l2cap_txwin_setup(struct l2cap_chan *chan) 3378{ 3379 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW && 3380 __l2cap_ews_supported(chan->conn)) { 3381 /* use extended control field */ 3382 set_bit(FLAG_EXT_CTRL, &chan->flags); 3383 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW; 3384 } else { 3385 chan->tx_win = min_t(u16, chan->tx_win, 3386 L2CAP_DEFAULT_TX_WINDOW); 3387 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW; 3388 } 3389 chan->ack_win = chan->tx_win; 3390} 3391 3392static void l2cap_mtu_auto(struct l2cap_chan *chan) 3393{ 3394 struct hci_conn *conn = chan->conn->hcon; 3395 3396 chan->imtu = L2CAP_DEFAULT_MIN_MTU; 3397 3398 /* The 2-DH1 packet has between 2 and 56 information bytes 3399 * (including the 2-byte payload header) 3400 */ 3401 if (!(conn->pkt_type & HCI_2DH1)) 3402 chan->imtu = 54; 3403 3404 /* The 3-DH1 packet has between 2 and 85 information bytes 3405 * (including the 2-byte payload header) 3406 */ 3407 if (!(conn->pkt_type & HCI_3DH1)) 3408 chan->imtu = 83; 3409 3410 /* The 2-DH3 packet has between 2 and 369 information bytes 3411 * (including the 2-byte payload header) 3412 */ 3413 if (!(conn->pkt_type & HCI_2DH3)) 3414 chan->imtu = 367; 3415 3416 /* The 3-DH3 packet has between 2 and 554 information bytes 3417 * (including the 2-byte payload header) 3418 */ 3419 if (!(conn->pkt_type & HCI_3DH3)) 3420 chan->imtu = 552; 3421 3422 /* The 2-DH5 packet has between 2 and 681 information bytes 3423 * (including the 2-byte payload header) 3424 */ 3425 if (!(conn->pkt_type & HCI_2DH5)) 3426 chan->imtu = 679; 3427 3428 /* The 3-DH5 packet has between 2 and 1023 information bytes 3429 * (including the 2-byte payload header) 3430 */ 3431 if (!(conn->pkt_type & HCI_3DH5)) 3432 chan->imtu = 1021; 3433} 3434 3435static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size) 3436{ 3437 struct l2cap_conf_req *req = data; 3438 struct l2cap_conf_rfc rfc = { .mode = chan->mode }; 3439 void *ptr = req->data; 3440 void *endptr = data + data_size; 3441 u16 size; 3442 3443 BT_DBG("chan %p", chan); 3444 3445 if (chan->num_conf_req || chan->num_conf_rsp) 3446 goto done; 3447 3448 switch (chan->mode) { 3449 case L2CAP_MODE_STREAMING: 3450 case L2CAP_MODE_ERTM: 3451 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) 3452 break; 3453 3454 if (__l2cap_efs_supported(chan->conn)) 3455 set_bit(FLAG_EFS_ENABLE, &chan->flags); 3456 3457 fallthrough; 3458 default: 3459 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask); 3460 break; 3461 } 3462 3463done: 3464 if (chan->imtu != L2CAP_DEFAULT_MTU) { 3465 if (!chan->imtu) 3466 l2cap_mtu_auto(chan); 3467 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, 3468 endptr - ptr); 3469 } 3470 3471 switch (chan->mode) { 3472 case L2CAP_MODE_BASIC: 3473 if (disable_ertm) 3474 break; 3475 3476 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) && 3477 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING)) 3478 break; 3479 3480 rfc.mode = L2CAP_MODE_BASIC; 3481 rfc.txwin_size = 0; 3482 rfc.max_transmit = 0; 3483 rfc.retrans_timeout = 0; 3484 rfc.monitor_timeout = 0; 3485 rfc.max_pdu_size = 0; 3486 3487 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), 3488 (unsigned long) &rfc, endptr - ptr); 3489 break; 3490 3491 case L2CAP_MODE_ERTM: 3492 rfc.mode = L2CAP_MODE_ERTM; 3493 rfc.max_transmit = chan->max_tx; 3494 3495 __l2cap_set_ertm_timeouts(chan, &rfc); 3496 3497 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu - 3498 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE - 3499 L2CAP_FCS_SIZE); 3500 rfc.max_pdu_size = cpu_to_le16(size); 3501 3502 l2cap_txwin_setup(chan); 3503 3504 rfc.txwin_size = min_t(u16, chan->tx_win, 3505 L2CAP_DEFAULT_TX_WINDOW); 3506 3507 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), 3508 (unsigned long) &rfc, endptr - ptr); 3509 3510 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) 3511 l2cap_add_opt_efs(&ptr, chan, endptr - ptr); 3512 3513 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 3514 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2, 3515 chan->tx_win, endptr - ptr); 3516 3517 if (chan->conn->feat_mask & L2CAP_FEAT_FCS) 3518 if (chan->fcs == L2CAP_FCS_NONE || 3519 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) { 3520 chan->fcs = L2CAP_FCS_NONE; 3521 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, 3522 chan->fcs, endptr - ptr); 3523 } 3524 break; 3525 3526 case L2CAP_MODE_STREAMING: 3527 l2cap_txwin_setup(chan); 3528 rfc.mode = L2CAP_MODE_STREAMING; 3529 rfc.txwin_size = 0; 3530 rfc.max_transmit = 0; 3531 rfc.retrans_timeout = 0; 3532 rfc.monitor_timeout = 0; 3533 3534 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu - 3535 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE - 3536 L2CAP_FCS_SIZE); 3537 rfc.max_pdu_size = cpu_to_le16(size); 3538 3539 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), 3540 (unsigned long) &rfc, endptr - ptr); 3541 3542 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) 3543 l2cap_add_opt_efs(&ptr, chan, endptr - ptr); 3544 3545 if (chan->conn->feat_mask & L2CAP_FEAT_FCS) 3546 if (chan->fcs == L2CAP_FCS_NONE || 3547 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) { 3548 chan->fcs = L2CAP_FCS_NONE; 3549 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, 3550 chan->fcs, endptr - ptr); 3551 } 3552 break; 3553 } 3554 3555 req->dcid = cpu_to_le16(chan->dcid); 3556 req->flags = cpu_to_le16(0); 3557 3558 return ptr - data; 3559} 3560 3561static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size) 3562{ 3563 struct l2cap_conf_rsp *rsp = data; 3564 void *ptr = rsp->data; 3565 void *endptr = data + data_size; 3566 void *req = chan->conf_req; 3567 int len = chan->conf_len; 3568 int type, hint, olen; 3569 unsigned long val; 3570 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC }; 3571 struct l2cap_conf_efs efs; 3572 u8 remote_efs = 0; 3573 u16 mtu = L2CAP_DEFAULT_MTU; 3574 u16 result = L2CAP_CONF_SUCCESS; 3575 u16 size; 3576 3577 BT_DBG("chan %p", chan); 3578 3579 while (len >= L2CAP_CONF_OPT_SIZE) { 3580 len -= l2cap_get_conf_opt(&req, &type, &olen, &val); 3581 if (len < 0) 3582 break; 3583 3584 hint = type & L2CAP_CONF_HINT; 3585 type &= L2CAP_CONF_MASK; 3586 3587 switch (type) { 3588 case L2CAP_CONF_MTU: 3589 if (olen != 2) 3590 break; 3591 mtu = val; 3592 break; 3593 3594 case L2CAP_CONF_FLUSH_TO: 3595 if (olen != 2) 3596 break; 3597 chan->flush_to = val; 3598 break; 3599 3600 case L2CAP_CONF_QOS: 3601 break; 3602 3603 case L2CAP_CONF_RFC: 3604 if (olen != sizeof(rfc)) 3605 break; 3606 memcpy(&rfc, (void *) val, olen); 3607 break; 3608 3609 case L2CAP_CONF_FCS: 3610 if (olen != 1) 3611 break; 3612 if (val == L2CAP_FCS_NONE) 3613 set_bit(CONF_RECV_NO_FCS, &chan->conf_state); 3614 break; 3615 3616 case L2CAP_CONF_EFS: 3617 if (olen != sizeof(efs)) 3618 break; 3619 remote_efs = 1; 3620 memcpy(&efs, (void *) val, olen); 3621 break; 3622 3623 case L2CAP_CONF_EWS: 3624 if (olen != 2) 3625 break; 3626 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP)) 3627 return -ECONNREFUSED; 3628 set_bit(FLAG_EXT_CTRL, &chan->flags); 3629 set_bit(CONF_EWS_RECV, &chan->conf_state); 3630 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW; 3631 chan->remote_tx_win = val; 3632 break; 3633 3634 default: 3635 if (hint) 3636 break; 3637 result = L2CAP_CONF_UNKNOWN; 3638 *((u8 *) ptr++) = type; 3639 break; 3640 } 3641 } 3642 3643 if (chan->num_conf_rsp || chan->num_conf_req > 1) 3644 goto done; 3645 3646 switch (chan->mode) { 3647 case L2CAP_MODE_STREAMING: 3648 case L2CAP_MODE_ERTM: 3649 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) { 3650 chan->mode = l2cap_select_mode(rfc.mode, 3651 chan->conn->feat_mask); 3652 break; 3653 } 3654 3655 if (remote_efs) { 3656 if (__l2cap_efs_supported(chan->conn)) 3657 set_bit(FLAG_EFS_ENABLE, &chan->flags); 3658 else 3659 return -ECONNREFUSED; 3660 } 3661 3662 if (chan->mode != rfc.mode) 3663 return -ECONNREFUSED; 3664 3665 break; 3666 } 3667 3668done: 3669 if (chan->mode != rfc.mode) { 3670 result = L2CAP_CONF_UNACCEPT; 3671 rfc.mode = chan->mode; 3672 3673 if (chan->num_conf_rsp == 1) 3674 return -ECONNREFUSED; 3675 3676 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), 3677 (unsigned long) &rfc, endptr - ptr); 3678 } 3679 3680 if (result == L2CAP_CONF_SUCCESS) { 3681 /* Configure output options and let the other side know 3682 * which ones we don't like. */ 3683 3684 if (mtu < L2CAP_DEFAULT_MIN_MTU) 3685 result = L2CAP_CONF_UNACCEPT; 3686 else { 3687 chan->omtu = mtu; 3688 set_bit(CONF_MTU_DONE, &chan->conf_state); 3689 } 3690 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr); 3691 3692 if (remote_efs) { 3693 if (chan->local_stype != L2CAP_SERV_NOTRAFIC && 3694 efs.stype != L2CAP_SERV_NOTRAFIC && 3695 efs.stype != chan->local_stype) { 3696 3697 result = L2CAP_CONF_UNACCEPT; 3698 3699 if (chan->num_conf_req >= 1) 3700 return -ECONNREFUSED; 3701 3702 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, 3703 sizeof(efs), 3704 (unsigned long) &efs, endptr - ptr); 3705 } else { 3706 /* Send PENDING Conf Rsp */ 3707 result = L2CAP_CONF_PENDING; 3708 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state); 3709 } 3710 } 3711 3712 switch (rfc.mode) { 3713 case L2CAP_MODE_BASIC: 3714 chan->fcs = L2CAP_FCS_NONE; 3715 set_bit(CONF_MODE_DONE, &chan->conf_state); 3716 break; 3717 3718 case L2CAP_MODE_ERTM: 3719 if (!test_bit(CONF_EWS_RECV, &chan->conf_state)) 3720 chan->remote_tx_win = rfc.txwin_size; 3721 else 3722 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW; 3723 3724 chan->remote_max_tx = rfc.max_transmit; 3725 3726 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size), 3727 chan->conn->mtu - L2CAP_EXT_HDR_SIZE - 3728 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE); 3729 rfc.max_pdu_size = cpu_to_le16(size); 3730 chan->remote_mps = size; 3731 3732 __l2cap_set_ertm_timeouts(chan, &rfc); 3733 3734 set_bit(CONF_MODE_DONE, &chan->conf_state); 3735 3736 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, 3737 sizeof(rfc), (unsigned long) &rfc, endptr - ptr); 3738 3739 if (remote_efs && 3740 test_bit(FLAG_EFS_ENABLE, &chan->flags)) { 3741 chan->remote_id = efs.id; 3742 chan->remote_stype = efs.stype; 3743 chan->remote_msdu = le16_to_cpu(efs.msdu); 3744 chan->remote_flush_to = 3745 le32_to_cpu(efs.flush_to); 3746 chan->remote_acc_lat = 3747 le32_to_cpu(efs.acc_lat); 3748 chan->remote_sdu_itime = 3749 le32_to_cpu(efs.sdu_itime); 3750 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, 3751 sizeof(efs), 3752 (unsigned long) &efs, endptr - ptr); 3753 } 3754 break; 3755 3756 case L2CAP_MODE_STREAMING: 3757 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size), 3758 chan->conn->mtu - L2CAP_EXT_HDR_SIZE - 3759 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE); 3760 rfc.max_pdu_size = cpu_to_le16(size); 3761 chan->remote_mps = size; 3762 3763 set_bit(CONF_MODE_DONE, &chan->conf_state); 3764 3765 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), 3766 (unsigned long) &rfc, endptr - ptr); 3767 3768 break; 3769 3770 default: 3771 result = L2CAP_CONF_UNACCEPT; 3772 3773 memset(&rfc, 0, sizeof(rfc)); 3774 rfc.mode = chan->mode; 3775 } 3776 3777 if (result == L2CAP_CONF_SUCCESS) 3778 set_bit(CONF_OUTPUT_DONE, &chan->conf_state); 3779 } 3780 rsp->scid = cpu_to_le16(chan->dcid); 3781 rsp->result = cpu_to_le16(result); 3782 rsp->flags = cpu_to_le16(0); 3783 3784 return ptr - data; 3785} 3786 3787static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, 3788 void *data, size_t size, u16 *result) 3789{ 3790 struct l2cap_conf_req *req = data; 3791 void *ptr = req->data; 3792 void *endptr = data + size; 3793 int type, olen; 3794 unsigned long val; 3795 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC }; 3796 struct l2cap_conf_efs efs; 3797 3798 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data); 3799 3800 while (len >= L2CAP_CONF_OPT_SIZE) { 3801 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val); 3802 if (len < 0) 3803 break; 3804 3805 switch (type) { 3806 case L2CAP_CONF_MTU: 3807 if (olen != 2) 3808 break; 3809 if (val < L2CAP_DEFAULT_MIN_MTU) { 3810 *result = L2CAP_CONF_UNACCEPT; 3811 chan->imtu = L2CAP_DEFAULT_MIN_MTU; 3812 } else 3813 chan->imtu = val; 3814 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, 3815 endptr - ptr); 3816 break; 3817 3818 case L2CAP_CONF_FLUSH_TO: 3819 if (olen != 2) 3820 break; 3821 chan->flush_to = val; 3822 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2, 3823 chan->flush_to, endptr - ptr); 3824 break; 3825 3826 case L2CAP_CONF_RFC: 3827 if (olen != sizeof(rfc)) 3828 break; 3829 memcpy(&rfc, (void *)val, olen); 3830 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) && 3831 rfc.mode != chan->mode) 3832 return -ECONNREFUSED; 3833 chan->fcs = 0; 3834 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), 3835 (unsigned long) &rfc, endptr - ptr); 3836 break; 3837 3838 case L2CAP_CONF_EWS: 3839 if (olen != 2) 3840 break; 3841 chan->ack_win = min_t(u16, val, chan->ack_win); 3842 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2, 3843 chan->tx_win, endptr - ptr); 3844 break; 3845 3846 case L2CAP_CONF_EFS: 3847 if (olen != sizeof(efs)) 3848 break; 3849 memcpy(&efs, (void *)val, olen); 3850 if (chan->local_stype != L2CAP_SERV_NOTRAFIC && 3851 efs.stype != L2CAP_SERV_NOTRAFIC && 3852 efs.stype != chan->local_stype) 3853 return -ECONNREFUSED; 3854 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs), 3855 (unsigned long) &efs, endptr - ptr); 3856 break; 3857 3858 case L2CAP_CONF_FCS: 3859 if (olen != 1) 3860 break; 3861 if (*result == L2CAP_CONF_PENDING) 3862 if (val == L2CAP_FCS_NONE) 3863 set_bit(CONF_RECV_NO_FCS, 3864 &chan->conf_state); 3865 break; 3866 } 3867 } 3868 3869 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode) 3870 return -ECONNREFUSED; 3871 3872 chan->mode = rfc.mode; 3873 3874 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) { 3875 switch (rfc.mode) { 3876 case L2CAP_MODE_ERTM: 3877 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout); 3878 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout); 3879 chan->mps = le16_to_cpu(rfc.max_pdu_size); 3880 if (!test_bit(FLAG_EXT_CTRL, &chan->flags)) 3881 chan->ack_win = min_t(u16, chan->ack_win, 3882 rfc.txwin_size); 3883 3884 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) { 3885 chan->local_msdu = le16_to_cpu(efs.msdu); 3886 chan->local_sdu_itime = 3887 le32_to_cpu(efs.sdu_itime); 3888 chan->local_acc_lat = le32_to_cpu(efs.acc_lat); 3889 chan->local_flush_to = 3890 le32_to_cpu(efs.flush_to); 3891 } 3892 break; 3893 3894 case L2CAP_MODE_STREAMING: 3895 chan->mps = le16_to_cpu(rfc.max_pdu_size); 3896 } 3897 } 3898 3899 req->dcid = cpu_to_le16(chan->dcid); 3900 req->flags = cpu_to_le16(0); 3901 3902 return ptr - data; 3903} 3904 3905static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data, 3906 u16 result, u16 flags) 3907{ 3908 struct l2cap_conf_rsp *rsp = data; 3909 void *ptr = rsp->data; 3910 3911 BT_DBG("chan %p", chan); 3912 3913 rsp->scid = cpu_to_le16(chan->dcid); 3914 rsp->result = cpu_to_le16(result); 3915 rsp->flags = cpu_to_le16(flags); 3916 3917 return ptr - data; 3918} 3919 3920void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan) 3921{ 3922 struct l2cap_le_conn_rsp rsp; 3923 struct l2cap_conn *conn = chan->conn; 3924 3925 BT_DBG("chan %p", chan); 3926 3927 rsp.dcid = cpu_to_le16(chan->scid); 3928 rsp.mtu = cpu_to_le16(chan->imtu); 3929 rsp.mps = cpu_to_le16(chan->mps); 3930 rsp.credits = cpu_to_le16(chan->rx_credits); 3931 rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS); 3932 3933 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), 3934 &rsp); 3935} 3936 3937static void l2cap_ecred_list_defer(struct l2cap_chan *chan, void *data) 3938{ 3939 int *result = data; 3940 3941 if (*result || test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) 3942 return; 3943 3944 switch (chan->state) { 3945 case BT_CONNECT2: 3946 /* If channel still pending accept add to result */ 3947 (*result)++; 3948 return; 3949 case BT_CONNECTED: 3950 return; 3951 default: 3952 /* If not connected or pending accept it has been refused */ 3953 *result = -ECONNREFUSED; 3954 return; 3955 } 3956} 3957 3958struct l2cap_ecred_rsp_data { 3959 struct { 3960 struct l2cap_ecred_conn_rsp rsp; 3961 __le16 scid[L2CAP_ECRED_MAX_CID]; 3962 } __packed pdu; 3963 int count; 3964}; 3965 3966static void l2cap_ecred_rsp_defer(struct l2cap_chan *chan, void *data) 3967{ 3968 struct l2cap_ecred_rsp_data *rsp = data; 3969 3970 if (test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) 3971 return; 3972 3973 /* Reset ident so only one response is sent */ 3974 chan->ident = 0; 3975 3976 /* Include all channels pending with the same ident */ 3977 if (!rsp->pdu.rsp.result) 3978 rsp->pdu.rsp.dcid[rsp->count++] = cpu_to_le16(chan->scid); 3979 else 3980 l2cap_chan_del(chan, ECONNRESET); 3981} 3982 3983void __l2cap_ecred_conn_rsp_defer(struct l2cap_chan *chan) 3984{ 3985 struct l2cap_conn *conn = chan->conn; 3986 struct l2cap_ecred_rsp_data data; 3987 u16 id = chan->ident; 3988 int result = 0; 3989 3990 if (!id) 3991 return; 3992 3993 BT_DBG("chan %p id %d", chan, id); 3994 3995 memset(&data, 0, sizeof(data)); 3996 3997 data.pdu.rsp.mtu = cpu_to_le16(chan->imtu); 3998 data.pdu.rsp.mps = cpu_to_le16(chan->mps); 3999 data.pdu.rsp.credits = cpu_to_le16(chan->rx_credits); 4000 data.pdu.rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS); 4001 4002 /* Verify that all channels are ready */ 4003 __l2cap_chan_list_id(conn, id, l2cap_ecred_list_defer, &result); 4004 4005 if (result > 0) 4006 return; 4007 4008 if (result < 0) 4009 data.pdu.rsp.result = cpu_to_le16(L2CAP_CR_LE_AUTHORIZATION); 4010 4011 /* Build response */ 4012 __l2cap_chan_list_id(conn, id, l2cap_ecred_rsp_defer, &data); 4013 4014 l2cap_send_cmd(conn, id, L2CAP_ECRED_CONN_RSP, 4015 sizeof(data.pdu.rsp) + (data.count * sizeof(__le16)), 4016 &data.pdu); 4017} 4018 4019void __l2cap_connect_rsp_defer(struct l2cap_chan *chan) 4020{ 4021 struct l2cap_conn_rsp rsp; 4022 struct l2cap_conn *conn = chan->conn; 4023 u8 buf[128]; 4024 u8 rsp_code; 4025 4026 rsp.scid = cpu_to_le16(chan->dcid); 4027 rsp.dcid = cpu_to_le16(chan->scid); 4028 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS); 4029 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 4030 4031 if (chan->hs_hcon) 4032 rsp_code = L2CAP_CREATE_CHAN_RSP; 4033 else 4034 rsp_code = L2CAP_CONN_RSP; 4035 4036 BT_DBG("chan %p rsp_code %u", chan, rsp_code); 4037 4038 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp); 4039 4040 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) 4041 return; 4042 4043 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 4044 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 4045 chan->num_conf_req++; 4046} 4047 4048static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len) 4049{ 4050 int type, olen; 4051 unsigned long val; 4052 /* Use sane default values in case a misbehaving remote device 4053 * did not send an RFC or extended window size option. 4054 */ 4055 u16 txwin_ext = chan->ack_win; 4056 struct l2cap_conf_rfc rfc = { 4057 .mode = chan->mode, 4058 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO), 4059 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO), 4060 .max_pdu_size = cpu_to_le16(chan->imtu), 4061 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW), 4062 }; 4063 4064 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len); 4065 4066 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING)) 4067 return; 4068 4069 while (len >= L2CAP_CONF_OPT_SIZE) { 4070 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val); 4071 if (len < 0) 4072 break; 4073 4074 switch (type) { 4075 case L2CAP_CONF_RFC: 4076 if (olen != sizeof(rfc)) 4077 break; 4078 memcpy(&rfc, (void *)val, olen); 4079 break; 4080 case L2CAP_CONF_EWS: 4081 if (olen != 2) 4082 break; 4083 txwin_ext = val; 4084 break; 4085 } 4086 } 4087 4088 switch (rfc.mode) { 4089 case L2CAP_MODE_ERTM: 4090 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout); 4091 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout); 4092 chan->mps = le16_to_cpu(rfc.max_pdu_size); 4093 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 4094 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext); 4095 else 4096 chan->ack_win = min_t(u16, chan->ack_win, 4097 rfc.txwin_size); 4098 break; 4099 case L2CAP_MODE_STREAMING: 4100 chan->mps = le16_to_cpu(rfc.max_pdu_size); 4101 } 4102} 4103 4104static inline int l2cap_command_rej(struct l2cap_conn *conn, 4105 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4106 u8 *data) 4107{ 4108 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data; 4109 4110 if (cmd_len < sizeof(*rej)) 4111 return -EPROTO; 4112 4113 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD) 4114 return 0; 4115 4116 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) && 4117 cmd->ident == conn->info_ident) { 4118 cancel_delayed_work(&conn->info_timer); 4119 4120 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 4121 conn->info_ident = 0; 4122 4123 l2cap_conn_start(conn); 4124 } 4125 4126 return 0; 4127} 4128 4129static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn, 4130 struct l2cap_cmd_hdr *cmd, 4131 u8 *data, u8 rsp_code, u8 amp_id) 4132{ 4133 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data; 4134 struct l2cap_conn_rsp rsp; 4135 struct l2cap_chan *chan = NULL, *pchan; 4136 int result, status = L2CAP_CS_NO_INFO; 4137 4138 u16 dcid = 0, scid = __le16_to_cpu(req->scid); 4139 __le16 psm = req->psm; 4140 4141 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid); 4142 4143 /* Check if we have socket listening on psm */ 4144 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src, 4145 &conn->hcon->dst, ACL_LINK); 4146 if (!pchan) { 4147 result = L2CAP_CR_BAD_PSM; 4148 goto sendresp; 4149 } 4150 4151 mutex_lock(&conn->chan_lock); 4152 l2cap_chan_lock(pchan); 4153 4154 /* Check if the ACL is secure enough (if not SDP) */ 4155 if (psm != cpu_to_le16(L2CAP_PSM_SDP) && 4156 !hci_conn_check_link_mode(conn->hcon)) { 4157 conn->disc_reason = HCI_ERROR_AUTH_FAILURE; 4158 result = L2CAP_CR_SEC_BLOCK; 4159 goto response; 4160 } 4161 4162 result = L2CAP_CR_NO_MEM; 4163 4164 /* Check for valid dynamic CID range (as per Erratum 3253) */ 4165 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) { 4166 result = L2CAP_CR_INVALID_SCID; 4167 goto response; 4168 } 4169 4170 /* Check if we already have channel with that dcid */ 4171 if (__l2cap_get_chan_by_dcid(conn, scid)) { 4172 result = L2CAP_CR_SCID_IN_USE; 4173 goto response; 4174 } 4175 4176 chan = pchan->ops->new_connection(pchan); 4177 if (!chan) 4178 goto response; 4179 4180 /* For certain devices (ex: HID mouse), support for authentication, 4181 * pairing and bonding is optional. For such devices, inorder to avoid 4182 * the ACL alive for too long after L2CAP disconnection, reset the ACL 4183 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect. 4184 */ 4185 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT; 4186 4187 bacpy(&chan->src, &conn->hcon->src); 4188 bacpy(&chan->dst, &conn->hcon->dst); 4189 chan->src_type = bdaddr_src_type(conn->hcon); 4190 chan->dst_type = bdaddr_dst_type(conn->hcon); 4191 chan->psm = psm; 4192 chan->dcid = scid; 4193 chan->local_amp_id = amp_id; 4194 4195 __l2cap_chan_add(conn, chan); 4196 4197 dcid = chan->scid; 4198 4199 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 4200 4201 chan->ident = cmd->ident; 4202 4203 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) { 4204 if (l2cap_chan_check_security(chan, false)) { 4205 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 4206 l2cap_state_change(chan, BT_CONNECT2); 4207 result = L2CAP_CR_PEND; 4208 status = L2CAP_CS_AUTHOR_PEND; 4209 chan->ops->defer(chan); 4210 } else { 4211 /* Force pending result for AMP controllers. 4212 * The connection will succeed after the 4213 * physical link is up. 4214 */ 4215 if (amp_id == AMP_ID_BREDR) { 4216 l2cap_state_change(chan, BT_CONFIG); 4217 result = L2CAP_CR_SUCCESS; 4218 } else { 4219 l2cap_state_change(chan, BT_CONNECT2); 4220 result = L2CAP_CR_PEND; 4221 } 4222 status = L2CAP_CS_NO_INFO; 4223 } 4224 } else { 4225 l2cap_state_change(chan, BT_CONNECT2); 4226 result = L2CAP_CR_PEND; 4227 status = L2CAP_CS_AUTHEN_PEND; 4228 } 4229 } else { 4230 l2cap_state_change(chan, BT_CONNECT2); 4231 result = L2CAP_CR_PEND; 4232 status = L2CAP_CS_NO_INFO; 4233 } 4234 4235response: 4236 l2cap_chan_unlock(pchan); 4237 mutex_unlock(&conn->chan_lock); 4238 l2cap_chan_put(pchan); 4239 4240sendresp: 4241 rsp.scid = cpu_to_le16(scid); 4242 rsp.dcid = cpu_to_le16(dcid); 4243 rsp.result = cpu_to_le16(result); 4244 rsp.status = cpu_to_le16(status); 4245 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp); 4246 4247 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) { 4248 struct l2cap_info_req info; 4249 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK); 4250 4251 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT; 4252 conn->info_ident = l2cap_get_ident(conn); 4253 4254 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT); 4255 4256 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ, 4257 sizeof(info), &info); 4258 } 4259 4260 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) && 4261 result == L2CAP_CR_SUCCESS) { 4262 u8 buf[128]; 4263 set_bit(CONF_REQ_SENT, &chan->conf_state); 4264 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 4265 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 4266 chan->num_conf_req++; 4267 } 4268 4269 return chan; 4270} 4271 4272static int l2cap_connect_req(struct l2cap_conn *conn, 4273 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data) 4274{ 4275 struct hci_dev *hdev = conn->hcon->hdev; 4276 struct hci_conn *hcon = conn->hcon; 4277 4278 if (cmd_len < sizeof(struct l2cap_conn_req)) 4279 return -EPROTO; 4280 4281 hci_dev_lock(hdev); 4282 if (hci_dev_test_flag(hdev, HCI_MGMT) && 4283 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags)) 4284 mgmt_device_connected(hdev, hcon, 0, NULL, 0); 4285 hci_dev_unlock(hdev); 4286 4287 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0); 4288 return 0; 4289} 4290 4291static int l2cap_connect_create_rsp(struct l2cap_conn *conn, 4292 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4293 u8 *data) 4294{ 4295 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data; 4296 u16 scid, dcid, result, status; 4297 struct l2cap_chan *chan; 4298 u8 req[128]; 4299 int err; 4300 4301 if (cmd_len < sizeof(*rsp)) 4302 return -EPROTO; 4303 4304 scid = __le16_to_cpu(rsp->scid); 4305 dcid = __le16_to_cpu(rsp->dcid); 4306 result = __le16_to_cpu(rsp->result); 4307 status = __le16_to_cpu(rsp->status); 4308 4309 if (result == L2CAP_CR_SUCCESS && (dcid < L2CAP_CID_DYN_START || 4310 dcid > L2CAP_CID_DYN_END)) 4311 return -EPROTO; 4312 4313 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x", 4314 dcid, scid, result, status); 4315 4316 mutex_lock(&conn->chan_lock); 4317 4318 if (scid) { 4319 chan = __l2cap_get_chan_by_scid(conn, scid); 4320 if (!chan) { 4321 err = -EBADSLT; 4322 goto unlock; 4323 } 4324 } else { 4325 chan = __l2cap_get_chan_by_ident(conn, cmd->ident); 4326 if (!chan) { 4327 err = -EBADSLT; 4328 goto unlock; 4329 } 4330 } 4331 4332 chan = l2cap_chan_hold_unless_zero(chan); 4333 if (!chan) { 4334 err = -EBADSLT; 4335 goto unlock; 4336 } 4337 4338 err = 0; 4339 4340 l2cap_chan_lock(chan); 4341 4342 switch (result) { 4343 case L2CAP_CR_SUCCESS: 4344 if (__l2cap_get_chan_by_dcid(conn, dcid)) { 4345 err = -EBADSLT; 4346 break; 4347 } 4348 4349 l2cap_state_change(chan, BT_CONFIG); 4350 chan->ident = 0; 4351 chan->dcid = dcid; 4352 clear_bit(CONF_CONNECT_PEND, &chan->conf_state); 4353 4354 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) 4355 break; 4356 4357 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 4358 l2cap_build_conf_req(chan, req, sizeof(req)), req); 4359 chan->num_conf_req++; 4360 break; 4361 4362 case L2CAP_CR_PEND: 4363 set_bit(CONF_CONNECT_PEND, &chan->conf_state); 4364 break; 4365 4366 default: 4367 l2cap_chan_del(chan, ECONNREFUSED); 4368 break; 4369 } 4370 4371 l2cap_chan_unlock(chan); 4372 l2cap_chan_put(chan); 4373 4374unlock: 4375 mutex_unlock(&conn->chan_lock); 4376 4377 return err; 4378} 4379 4380static inline void set_default_fcs(struct l2cap_chan *chan) 4381{ 4382 /* FCS is enabled only in ERTM or streaming mode, if one or both 4383 * sides request it. 4384 */ 4385 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING) 4386 chan->fcs = L2CAP_FCS_NONE; 4387 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) 4388 chan->fcs = L2CAP_FCS_CRC16; 4389} 4390 4391static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data, 4392 u8 ident, u16 flags) 4393{ 4394 struct l2cap_conn *conn = chan->conn; 4395 4396 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident, 4397 flags); 4398 4399 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state); 4400 set_bit(CONF_OUTPUT_DONE, &chan->conf_state); 4401 4402 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP, 4403 l2cap_build_conf_rsp(chan, data, 4404 L2CAP_CONF_SUCCESS, flags), data); 4405} 4406 4407static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident, 4408 u16 scid, u16 dcid) 4409{ 4410 struct l2cap_cmd_rej_cid rej; 4411 4412 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID); 4413 rej.scid = __cpu_to_le16(scid); 4414 rej.dcid = __cpu_to_le16(dcid); 4415 4416 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej); 4417} 4418 4419static inline int l2cap_config_req(struct l2cap_conn *conn, 4420 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4421 u8 *data) 4422{ 4423 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data; 4424 u16 dcid, flags; 4425 u8 rsp[64]; 4426 struct l2cap_chan *chan; 4427 int len, err = 0; 4428 4429 if (cmd_len < sizeof(*req)) 4430 return -EPROTO; 4431 4432 dcid = __le16_to_cpu(req->dcid); 4433 flags = __le16_to_cpu(req->flags); 4434 4435 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags); 4436 4437 chan = l2cap_get_chan_by_scid(conn, dcid); 4438 if (!chan) { 4439 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0); 4440 return 0; 4441 } 4442 4443 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2 && 4444 chan->state != BT_CONNECTED) { 4445 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid, 4446 chan->dcid); 4447 goto unlock; 4448 } 4449 4450 /* Reject if config buffer is too small. */ 4451 len = cmd_len - sizeof(*req); 4452 if (chan->conf_len + len > sizeof(chan->conf_req)) { 4453 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, 4454 l2cap_build_conf_rsp(chan, rsp, 4455 L2CAP_CONF_REJECT, flags), rsp); 4456 goto unlock; 4457 } 4458 4459 /* Store config. */ 4460 memcpy(chan->conf_req + chan->conf_len, req->data, len); 4461 chan->conf_len += len; 4462 4463 if (flags & L2CAP_CONF_FLAG_CONTINUATION) { 4464 /* Incomplete config. Send empty response. */ 4465 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, 4466 l2cap_build_conf_rsp(chan, rsp, 4467 L2CAP_CONF_SUCCESS, flags), rsp); 4468 goto unlock; 4469 } 4470 4471 /* Complete config. */ 4472 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp)); 4473 if (len < 0) { 4474 l2cap_send_disconn_req(chan, ECONNRESET); 4475 goto unlock; 4476 } 4477 4478 chan->ident = cmd->ident; 4479 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp); 4480 if (chan->num_conf_rsp < L2CAP_CONF_MAX_CONF_RSP) 4481 chan->num_conf_rsp++; 4482 4483 /* Reset config buffer. */ 4484 chan->conf_len = 0; 4485 4486 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) 4487 goto unlock; 4488 4489 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) { 4490 set_default_fcs(chan); 4491 4492 if (chan->mode == L2CAP_MODE_ERTM || 4493 chan->mode == L2CAP_MODE_STREAMING) 4494 err = l2cap_ertm_init(chan); 4495 4496 if (err < 0) 4497 l2cap_send_disconn_req(chan, -err); 4498 else 4499 l2cap_chan_ready(chan); 4500 4501 goto unlock; 4502 } 4503 4504 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) { 4505 u8 buf[64]; 4506 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 4507 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 4508 chan->num_conf_req++; 4509 } 4510 4511 /* Got Conf Rsp PENDING from remote side and assume we sent 4512 Conf Rsp PENDING in the code above */ 4513 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) && 4514 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) { 4515 4516 /* check compatibility */ 4517 4518 /* Send rsp for BR/EDR channel */ 4519 if (!chan->hs_hcon) 4520 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags); 4521 else 4522 chan->ident = cmd->ident; 4523 } 4524 4525unlock: 4526 l2cap_chan_unlock(chan); 4527 l2cap_chan_put(chan); 4528 return err; 4529} 4530 4531static inline int l2cap_config_rsp(struct l2cap_conn *conn, 4532 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4533 u8 *data) 4534{ 4535 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data; 4536 u16 scid, flags, result; 4537 struct l2cap_chan *chan; 4538 int len = cmd_len - sizeof(*rsp); 4539 int err = 0; 4540 4541 if (cmd_len < sizeof(*rsp)) 4542 return -EPROTO; 4543 4544 scid = __le16_to_cpu(rsp->scid); 4545 flags = __le16_to_cpu(rsp->flags); 4546 result = __le16_to_cpu(rsp->result); 4547 4548 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags, 4549 result, len); 4550 4551 chan = l2cap_get_chan_by_scid(conn, scid); 4552 if (!chan) 4553 return 0; 4554 4555 switch (result) { 4556 case L2CAP_CONF_SUCCESS: 4557 l2cap_conf_rfc_get(chan, rsp->data, len); 4558 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state); 4559 break; 4560 4561 case L2CAP_CONF_PENDING: 4562 set_bit(CONF_REM_CONF_PEND, &chan->conf_state); 4563 4564 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) { 4565 char buf[64]; 4566 4567 len = l2cap_parse_conf_rsp(chan, rsp->data, len, 4568 buf, sizeof(buf), &result); 4569 if (len < 0) { 4570 l2cap_send_disconn_req(chan, ECONNRESET); 4571 goto done; 4572 } 4573 4574 if (!chan->hs_hcon) { 4575 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident, 4576 0); 4577 } else { 4578 if (l2cap_check_efs(chan)) { 4579 amp_create_logical_link(chan); 4580 chan->ident = cmd->ident; 4581 } 4582 } 4583 } 4584 goto done; 4585 4586 case L2CAP_CONF_UNACCEPT: 4587 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) { 4588 char req[64]; 4589 4590 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) { 4591 l2cap_send_disconn_req(chan, ECONNRESET); 4592 goto done; 4593 } 4594 4595 /* throw out any old stored conf requests */ 4596 result = L2CAP_CONF_SUCCESS; 4597 len = l2cap_parse_conf_rsp(chan, rsp->data, len, 4598 req, sizeof(req), &result); 4599 if (len < 0) { 4600 l2cap_send_disconn_req(chan, ECONNRESET); 4601 goto done; 4602 } 4603 4604 l2cap_send_cmd(conn, l2cap_get_ident(conn), 4605 L2CAP_CONF_REQ, len, req); 4606 chan->num_conf_req++; 4607 if (result != L2CAP_CONF_SUCCESS) 4608 goto done; 4609 break; 4610 } 4611 fallthrough; 4612 4613 default: 4614 l2cap_chan_set_err(chan, ECONNRESET); 4615 4616 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT); 4617 l2cap_send_disconn_req(chan, ECONNRESET); 4618 goto done; 4619 } 4620 4621 if (flags & L2CAP_CONF_FLAG_CONTINUATION) 4622 goto done; 4623 4624 set_bit(CONF_INPUT_DONE, &chan->conf_state); 4625 4626 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) { 4627 set_default_fcs(chan); 4628 4629 if (chan->mode == L2CAP_MODE_ERTM || 4630 chan->mode == L2CAP_MODE_STREAMING) 4631 err = l2cap_ertm_init(chan); 4632 4633 if (err < 0) 4634 l2cap_send_disconn_req(chan, -err); 4635 else 4636 l2cap_chan_ready(chan); 4637 } 4638 4639done: 4640 l2cap_chan_unlock(chan); 4641 l2cap_chan_put(chan); 4642 return err; 4643} 4644 4645static inline int l2cap_disconnect_req(struct l2cap_conn *conn, 4646 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4647 u8 *data) 4648{ 4649 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data; 4650 struct l2cap_disconn_rsp rsp; 4651 u16 dcid, scid; 4652 struct l2cap_chan *chan; 4653 4654 if (cmd_len != sizeof(*req)) 4655 return -EPROTO; 4656 4657 scid = __le16_to_cpu(req->scid); 4658 dcid = __le16_to_cpu(req->dcid); 4659 4660 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid); 4661 4662 chan = l2cap_get_chan_by_scid(conn, dcid); 4663 if (!chan) { 4664 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid); 4665 return 0; 4666 } 4667 4668 rsp.dcid = cpu_to_le16(chan->scid); 4669 rsp.scid = cpu_to_le16(chan->dcid); 4670 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp); 4671 4672 chan->ops->set_shutdown(chan); 4673 4674 l2cap_chan_unlock(chan); 4675 mutex_lock(&conn->chan_lock); 4676 l2cap_chan_lock(chan); 4677 l2cap_chan_del(chan, ECONNRESET); 4678 mutex_unlock(&conn->chan_lock); 4679 4680 chan->ops->close(chan); 4681 4682 l2cap_chan_unlock(chan); 4683 l2cap_chan_put(chan); 4684 4685 return 0; 4686} 4687 4688static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, 4689 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4690 u8 *data) 4691{ 4692 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data; 4693 u16 dcid, scid; 4694 struct l2cap_chan *chan; 4695 4696 if (cmd_len != sizeof(*rsp)) 4697 return -EPROTO; 4698 4699 scid = __le16_to_cpu(rsp->scid); 4700 dcid = __le16_to_cpu(rsp->dcid); 4701 4702 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid); 4703 4704 chan = l2cap_get_chan_by_scid(conn, scid); 4705 if (!chan) { 4706 return 0; 4707 } 4708 4709 if (chan->state != BT_DISCONN) { 4710 l2cap_chan_unlock(chan); 4711 l2cap_chan_put(chan); 4712 return 0; 4713 } 4714 4715 l2cap_chan_unlock(chan); 4716 mutex_lock(&conn->chan_lock); 4717 l2cap_chan_lock(chan); 4718 l2cap_chan_del(chan, 0); 4719 mutex_unlock(&conn->chan_lock); 4720 4721 chan->ops->close(chan); 4722 4723 l2cap_chan_unlock(chan); 4724 l2cap_chan_put(chan); 4725 4726 return 0; 4727} 4728 4729static inline int l2cap_information_req(struct l2cap_conn *conn, 4730 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4731 u8 *data) 4732{ 4733 struct l2cap_info_req *req = (struct l2cap_info_req *) data; 4734 u16 type; 4735 4736 if (cmd_len != sizeof(*req)) 4737 return -EPROTO; 4738 4739 type = __le16_to_cpu(req->type); 4740 4741 BT_DBG("type 0x%4.4x", type); 4742 4743 if (type == L2CAP_IT_FEAT_MASK) { 4744 u8 buf[8]; 4745 u32 feat_mask = l2cap_feat_mask; 4746 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf; 4747 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK); 4748 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS); 4749 if (!disable_ertm) 4750 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING 4751 | L2CAP_FEAT_FCS; 4752 if (conn->local_fixed_chan & L2CAP_FC_A2MP) 4753 feat_mask |= L2CAP_FEAT_EXT_FLOW 4754 | L2CAP_FEAT_EXT_WINDOW; 4755 4756 put_unaligned_le32(feat_mask, rsp->data); 4757 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf), 4758 buf); 4759 } else if (type == L2CAP_IT_FIXED_CHAN) { 4760 u8 buf[12]; 4761 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf; 4762 4763 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN); 4764 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS); 4765 rsp->data[0] = conn->local_fixed_chan; 4766 memset(rsp->data + 1, 0, 7); 4767 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf), 4768 buf); 4769 } else { 4770 struct l2cap_info_rsp rsp; 4771 rsp.type = cpu_to_le16(type); 4772 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP); 4773 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp), 4774 &rsp); 4775 } 4776 4777 return 0; 4778} 4779 4780static inline int l2cap_information_rsp(struct l2cap_conn *conn, 4781 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4782 u8 *data) 4783{ 4784 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data; 4785 u16 type, result; 4786 4787 if (cmd_len < sizeof(*rsp)) 4788 return -EPROTO; 4789 4790 type = __le16_to_cpu(rsp->type); 4791 result = __le16_to_cpu(rsp->result); 4792 4793 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result); 4794 4795 /* L2CAP Info req/rsp are unbound to channels, add extra checks */ 4796 if (cmd->ident != conn->info_ident || 4797 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) 4798 return 0; 4799 4800 cancel_delayed_work(&conn->info_timer); 4801 4802 if (result != L2CAP_IR_SUCCESS) { 4803 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 4804 conn->info_ident = 0; 4805 4806 l2cap_conn_start(conn); 4807 4808 return 0; 4809 } 4810 4811 switch (type) { 4812 case L2CAP_IT_FEAT_MASK: 4813 conn->feat_mask = get_unaligned_le32(rsp->data); 4814 4815 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) { 4816 struct l2cap_info_req req; 4817 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN); 4818 4819 conn->info_ident = l2cap_get_ident(conn); 4820 4821 l2cap_send_cmd(conn, conn->info_ident, 4822 L2CAP_INFO_REQ, sizeof(req), &req); 4823 } else { 4824 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 4825 conn->info_ident = 0; 4826 4827 l2cap_conn_start(conn); 4828 } 4829 break; 4830 4831 case L2CAP_IT_FIXED_CHAN: 4832 conn->remote_fixed_chan = rsp->data[0]; 4833 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 4834 conn->info_ident = 0; 4835 4836 l2cap_conn_start(conn); 4837 break; 4838 } 4839 4840 return 0; 4841} 4842 4843static int l2cap_create_channel_req(struct l2cap_conn *conn, 4844 struct l2cap_cmd_hdr *cmd, 4845 u16 cmd_len, void *data) 4846{ 4847 struct l2cap_create_chan_req *req = data; 4848 struct l2cap_create_chan_rsp rsp; 4849 struct l2cap_chan *chan; 4850 struct hci_dev *hdev; 4851 u16 psm, scid; 4852 4853 if (cmd_len != sizeof(*req)) 4854 return -EPROTO; 4855 4856 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP)) 4857 return -EINVAL; 4858 4859 psm = le16_to_cpu(req->psm); 4860 scid = le16_to_cpu(req->scid); 4861 4862 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id); 4863 4864 /* For controller id 0 make BR/EDR connection */ 4865 if (req->amp_id == AMP_ID_BREDR) { 4866 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP, 4867 req->amp_id); 4868 return 0; 4869 } 4870 4871 /* Validate AMP controller id */ 4872 hdev = hci_dev_get(req->amp_id); 4873 if (!hdev) 4874 goto error; 4875 4876 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) { 4877 hci_dev_put(hdev); 4878 goto error; 4879 } 4880 4881 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP, 4882 req->amp_id); 4883 if (chan) { 4884 struct amp_mgr *mgr = conn->hcon->amp_mgr; 4885 struct hci_conn *hs_hcon; 4886 4887 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK, 4888 &conn->hcon->dst); 4889 if (!hs_hcon) { 4890 hci_dev_put(hdev); 4891 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid, 4892 chan->dcid); 4893 return 0; 4894 } 4895 4896 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon); 4897 4898 mgr->bredr_chan = chan; 4899 chan->hs_hcon = hs_hcon; 4900 chan->fcs = L2CAP_FCS_NONE; 4901 conn->mtu = hdev->block_mtu; 4902 } 4903 4904 hci_dev_put(hdev); 4905 4906 return 0; 4907 4908error: 4909 rsp.dcid = 0; 4910 rsp.scid = cpu_to_le16(scid); 4911 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP); 4912 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 4913 4914 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP, 4915 sizeof(rsp), &rsp); 4916 4917 return 0; 4918} 4919 4920static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id) 4921{ 4922 struct l2cap_move_chan_req req; 4923 u8 ident; 4924 4925 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id); 4926 4927 ident = l2cap_get_ident(chan->conn); 4928 chan->ident = ident; 4929 4930 req.icid = cpu_to_le16(chan->scid); 4931 req.dest_amp_id = dest_amp_id; 4932 4933 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req), 4934 &req); 4935 4936 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT); 4937} 4938 4939static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result) 4940{ 4941 struct l2cap_move_chan_rsp rsp; 4942 4943 BT_DBG("chan %p, result 0x%4.4x", chan, result); 4944 4945 rsp.icid = cpu_to_le16(chan->dcid); 4946 rsp.result = cpu_to_le16(result); 4947 4948 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP, 4949 sizeof(rsp), &rsp); 4950} 4951 4952static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result) 4953{ 4954 struct l2cap_move_chan_cfm cfm; 4955 4956 BT_DBG("chan %p, result 0x%4.4x", chan, result); 4957 4958 chan->ident = l2cap_get_ident(chan->conn); 4959 4960 cfm.icid = cpu_to_le16(chan->scid); 4961 cfm.result = cpu_to_le16(result); 4962 4963 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM, 4964 sizeof(cfm), &cfm); 4965 4966 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT); 4967} 4968 4969static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid) 4970{ 4971 struct l2cap_move_chan_cfm cfm; 4972 4973 BT_DBG("conn %p, icid 0x%4.4x", conn, icid); 4974 4975 cfm.icid = cpu_to_le16(icid); 4976 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED); 4977 4978 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM, 4979 sizeof(cfm), &cfm); 4980} 4981 4982static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident, 4983 u16 icid) 4984{ 4985 struct l2cap_move_chan_cfm_rsp rsp; 4986 4987 BT_DBG("icid 0x%4.4x", icid); 4988 4989 rsp.icid = cpu_to_le16(icid); 4990 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp); 4991} 4992 4993static void __release_logical_link(struct l2cap_chan *chan) 4994{ 4995 chan->hs_hchan = NULL; 4996 chan->hs_hcon = NULL; 4997 4998 /* Placeholder - release the logical link */ 4999} 5000 5001static void l2cap_logical_fail(struct l2cap_chan *chan) 5002{ 5003 /* Logical link setup failed */ 5004 if (chan->state != BT_CONNECTED) { 5005 /* Create channel failure, disconnect */ 5006 l2cap_send_disconn_req(chan, ECONNRESET); 5007 return; 5008 } 5009 5010 switch (chan->move_role) { 5011 case L2CAP_MOVE_ROLE_RESPONDER: 5012 l2cap_move_done(chan); 5013 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP); 5014 break; 5015 case L2CAP_MOVE_ROLE_INITIATOR: 5016 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP || 5017 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) { 5018 /* Remote has only sent pending or 5019 * success responses, clean up 5020 */ 5021 l2cap_move_done(chan); 5022 } 5023 5024 /* Other amp move states imply that the move 5025 * has already aborted 5026 */ 5027 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5028 break; 5029 } 5030} 5031 5032static void l2cap_logical_finish_create(struct l2cap_chan *chan, 5033 struct hci_chan *hchan) 5034{ 5035 struct l2cap_conf_rsp rsp; 5036 5037 chan->hs_hchan = hchan; 5038 chan->hs_hcon->l2cap_data = chan->conn; 5039 5040 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0); 5041 5042 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) { 5043 int err; 5044 5045 set_default_fcs(chan); 5046 5047 err = l2cap_ertm_init(chan); 5048 if (err < 0) 5049 l2cap_send_disconn_req(chan, -err); 5050 else 5051 l2cap_chan_ready(chan); 5052 } 5053} 5054 5055static void l2cap_logical_finish_move(struct l2cap_chan *chan, 5056 struct hci_chan *hchan) 5057{ 5058 chan->hs_hcon = hchan->conn; 5059 chan->hs_hcon->l2cap_data = chan->conn; 5060 5061 BT_DBG("move_state %d", chan->move_state); 5062 5063 switch (chan->move_state) { 5064 case L2CAP_MOVE_WAIT_LOGICAL_COMP: 5065 /* Move confirm will be sent after a success 5066 * response is received 5067 */ 5068 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS; 5069 break; 5070 case L2CAP_MOVE_WAIT_LOGICAL_CFM: 5071 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 5072 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY; 5073 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) { 5074 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP; 5075 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED); 5076 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) { 5077 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM; 5078 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS); 5079 } 5080 break; 5081 default: 5082 /* Move was not in expected state, free the channel */ 5083 __release_logical_link(chan); 5084 5085 chan->move_state = L2CAP_MOVE_STABLE; 5086 } 5087} 5088 5089/* Call with chan locked */ 5090void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan, 5091 u8 status) 5092{ 5093 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status); 5094 5095 if (status) { 5096 l2cap_logical_fail(chan); 5097 __release_logical_link(chan); 5098 return; 5099 } 5100 5101 if (chan->state != BT_CONNECTED) { 5102 /* Ignore logical link if channel is on BR/EDR */ 5103 if (chan->local_amp_id != AMP_ID_BREDR) 5104 l2cap_logical_finish_create(chan, hchan); 5105 } else { 5106 l2cap_logical_finish_move(chan, hchan); 5107 } 5108} 5109 5110void l2cap_move_start(struct l2cap_chan *chan) 5111{ 5112 BT_DBG("chan %p", chan); 5113 5114 if (chan->local_amp_id == AMP_ID_BREDR) { 5115 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED) 5116 return; 5117 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR; 5118 chan->move_state = L2CAP_MOVE_WAIT_PREPARE; 5119 /* Placeholder - start physical link setup */ 5120 } else { 5121 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR; 5122 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS; 5123 chan->move_id = 0; 5124 l2cap_move_setup(chan); 5125 l2cap_send_move_chan_req(chan, 0); 5126 } 5127} 5128 5129static void l2cap_do_create(struct l2cap_chan *chan, int result, 5130 u8 local_amp_id, u8 remote_amp_id) 5131{ 5132 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state), 5133 local_amp_id, remote_amp_id); 5134 5135 chan->fcs = L2CAP_FCS_NONE; 5136 5137 /* Outgoing channel on AMP */ 5138 if (chan->state == BT_CONNECT) { 5139 if (result == L2CAP_CR_SUCCESS) { 5140 chan->local_amp_id = local_amp_id; 5141 l2cap_send_create_chan_req(chan, remote_amp_id); 5142 } else { 5143 /* Revert to BR/EDR connect */ 5144 l2cap_send_conn_req(chan); 5145 } 5146 5147 return; 5148 } 5149 5150 /* Incoming channel on AMP */ 5151 if (__l2cap_no_conn_pending(chan)) { 5152 struct l2cap_conn_rsp rsp; 5153 char buf[128]; 5154 rsp.scid = cpu_to_le16(chan->dcid); 5155 rsp.dcid = cpu_to_le16(chan->scid); 5156 5157 if (result == L2CAP_CR_SUCCESS) { 5158 /* Send successful response */ 5159 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS); 5160 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 5161 } else { 5162 /* Send negative response */ 5163 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM); 5164 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 5165 } 5166 5167 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP, 5168 sizeof(rsp), &rsp); 5169 5170 if (result == L2CAP_CR_SUCCESS) { 5171 l2cap_state_change(chan, BT_CONFIG); 5172 set_bit(CONF_REQ_SENT, &chan->conf_state); 5173 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn), 5174 L2CAP_CONF_REQ, 5175 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 5176 chan->num_conf_req++; 5177 } 5178 } 5179} 5180 5181static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id, 5182 u8 remote_amp_id) 5183{ 5184 l2cap_move_setup(chan); 5185 chan->move_id = local_amp_id; 5186 chan->move_state = L2CAP_MOVE_WAIT_RSP; 5187 5188 l2cap_send_move_chan_req(chan, remote_amp_id); 5189} 5190 5191static void l2cap_do_move_respond(struct l2cap_chan *chan, int result) 5192{ 5193 struct hci_chan *hchan = NULL; 5194 5195 /* Placeholder - get hci_chan for logical link */ 5196 5197 if (hchan) { 5198 if (hchan->state == BT_CONNECTED) { 5199 /* Logical link is ready to go */ 5200 chan->hs_hcon = hchan->conn; 5201 chan->hs_hcon->l2cap_data = chan->conn; 5202 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM; 5203 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS); 5204 5205 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS); 5206 } else { 5207 /* Wait for logical link to be ready */ 5208 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM; 5209 } 5210 } else { 5211 /* Logical link not available */ 5212 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED); 5213 } 5214} 5215 5216static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result) 5217{ 5218 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) { 5219 u8 rsp_result; 5220 if (result == -EINVAL) 5221 rsp_result = L2CAP_MR_BAD_ID; 5222 else 5223 rsp_result = L2CAP_MR_NOT_ALLOWED; 5224 5225 l2cap_send_move_chan_rsp(chan, rsp_result); 5226 } 5227 5228 chan->move_role = L2CAP_MOVE_ROLE_NONE; 5229 chan->move_state = L2CAP_MOVE_STABLE; 5230 5231 /* Restart data transmission */ 5232 l2cap_ertm_send(chan); 5233} 5234 5235/* Invoke with locked chan */ 5236void __l2cap_physical_cfm(struct l2cap_chan *chan, int result) 5237{ 5238 u8 local_amp_id = chan->local_amp_id; 5239 u8 remote_amp_id = chan->remote_amp_id; 5240 5241 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d", 5242 chan, result, local_amp_id, remote_amp_id); 5243 5244 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) 5245 return; 5246 5247 if (chan->state != BT_CONNECTED) { 5248 l2cap_do_create(chan, result, local_amp_id, remote_amp_id); 5249 } else if (result != L2CAP_MR_SUCCESS) { 5250 l2cap_do_move_cancel(chan, result); 5251 } else { 5252 switch (chan->move_role) { 5253 case L2CAP_MOVE_ROLE_INITIATOR: 5254 l2cap_do_move_initiate(chan, local_amp_id, 5255 remote_amp_id); 5256 break; 5257 case L2CAP_MOVE_ROLE_RESPONDER: 5258 l2cap_do_move_respond(chan, result); 5259 break; 5260 default: 5261 l2cap_do_move_cancel(chan, result); 5262 break; 5263 } 5264 } 5265} 5266 5267static inline int l2cap_move_channel_req(struct l2cap_conn *conn, 5268 struct l2cap_cmd_hdr *cmd, 5269 u16 cmd_len, void *data) 5270{ 5271 struct l2cap_move_chan_req *req = data; 5272 struct l2cap_move_chan_rsp rsp; 5273 struct l2cap_chan *chan; 5274 u16 icid = 0; 5275 u16 result = L2CAP_MR_NOT_ALLOWED; 5276 5277 if (cmd_len != sizeof(*req)) 5278 return -EPROTO; 5279 5280 icid = le16_to_cpu(req->icid); 5281 5282 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id); 5283 5284 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP)) 5285 return -EINVAL; 5286 5287 chan = l2cap_get_chan_by_dcid(conn, icid); 5288 if (!chan) { 5289 rsp.icid = cpu_to_le16(icid); 5290 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED); 5291 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP, 5292 sizeof(rsp), &rsp); 5293 return 0; 5294 } 5295 5296 chan->ident = cmd->ident; 5297 5298 if (chan->scid < L2CAP_CID_DYN_START || 5299 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY || 5300 (chan->mode != L2CAP_MODE_ERTM && 5301 chan->mode != L2CAP_MODE_STREAMING)) { 5302 result = L2CAP_MR_NOT_ALLOWED; 5303 goto send_move_response; 5304 } 5305 5306 if (chan->local_amp_id == req->dest_amp_id) { 5307 result = L2CAP_MR_SAME_ID; 5308 goto send_move_response; 5309 } 5310 5311 if (req->dest_amp_id != AMP_ID_BREDR) { 5312 struct hci_dev *hdev; 5313 hdev = hci_dev_get(req->dest_amp_id); 5314 if (!hdev || hdev->dev_type != HCI_AMP || 5315 !test_bit(HCI_UP, &hdev->flags)) { 5316 if (hdev) 5317 hci_dev_put(hdev); 5318 5319 result = L2CAP_MR_BAD_ID; 5320 goto send_move_response; 5321 } 5322 hci_dev_put(hdev); 5323 } 5324 5325 /* Detect a move collision. Only send a collision response 5326 * if this side has "lost", otherwise proceed with the move. 5327 * The winner has the larger bd_addr. 5328 */ 5329 if ((__chan_is_moving(chan) || 5330 chan->move_role != L2CAP_MOVE_ROLE_NONE) && 5331 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) { 5332 result = L2CAP_MR_COLLISION; 5333 goto send_move_response; 5334 } 5335 5336 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER; 5337 l2cap_move_setup(chan); 5338 chan->move_id = req->dest_amp_id; 5339 5340 if (req->dest_amp_id == AMP_ID_BREDR) { 5341 /* Moving to BR/EDR */ 5342 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 5343 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY; 5344 result = L2CAP_MR_PEND; 5345 } else { 5346 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM; 5347 result = L2CAP_MR_SUCCESS; 5348 } 5349 } else { 5350 chan->move_state = L2CAP_MOVE_WAIT_PREPARE; 5351 /* Placeholder - uncomment when amp functions are available */ 5352 /*amp_accept_physical(chan, req->dest_amp_id);*/ 5353 result = L2CAP_MR_PEND; 5354 } 5355 5356send_move_response: 5357 l2cap_send_move_chan_rsp(chan, result); 5358 5359 l2cap_chan_unlock(chan); 5360 l2cap_chan_put(chan); 5361 5362 return 0; 5363} 5364 5365static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result) 5366{ 5367 struct l2cap_chan *chan; 5368 struct hci_chan *hchan = NULL; 5369 5370 chan = l2cap_get_chan_by_scid(conn, icid); 5371 if (!chan) { 5372 l2cap_send_move_chan_cfm_icid(conn, icid); 5373 return; 5374 } 5375 5376 __clear_chan_timer(chan); 5377 if (result == L2CAP_MR_PEND) 5378 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT); 5379 5380 switch (chan->move_state) { 5381 case L2CAP_MOVE_WAIT_LOGICAL_COMP: 5382 /* Move confirm will be sent when logical link 5383 * is complete. 5384 */ 5385 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM; 5386 break; 5387 case L2CAP_MOVE_WAIT_RSP_SUCCESS: 5388 if (result == L2CAP_MR_PEND) { 5389 break; 5390 } else if (test_bit(CONN_LOCAL_BUSY, 5391 &chan->conn_state)) { 5392 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY; 5393 } else { 5394 /* Logical link is up or moving to BR/EDR, 5395 * proceed with move 5396 */ 5397 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP; 5398 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED); 5399 } 5400 break; 5401 case L2CAP_MOVE_WAIT_RSP: 5402 /* Moving to AMP */ 5403 if (result == L2CAP_MR_SUCCESS) { 5404 /* Remote is ready, send confirm immediately 5405 * after logical link is ready 5406 */ 5407 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM; 5408 } else { 5409 /* Both logical link and move success 5410 * are required to confirm 5411 */ 5412 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP; 5413 } 5414 5415 /* Placeholder - get hci_chan for logical link */ 5416 if (!hchan) { 5417 /* Logical link not available */ 5418 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5419 break; 5420 } 5421 5422 /* If the logical link is not yet connected, do not 5423 * send confirmation. 5424 */ 5425 if (hchan->state != BT_CONNECTED) 5426 break; 5427 5428 /* Logical link is already ready to go */ 5429 5430 chan->hs_hcon = hchan->conn; 5431 chan->hs_hcon->l2cap_data = chan->conn; 5432 5433 if (result == L2CAP_MR_SUCCESS) { 5434 /* Can confirm now */ 5435 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED); 5436 } else { 5437 /* Now only need move success 5438 * to confirm 5439 */ 5440 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS; 5441 } 5442 5443 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS); 5444 break; 5445 default: 5446 /* Any other amp move state means the move failed. */ 5447 chan->move_id = chan->local_amp_id; 5448 l2cap_move_done(chan); 5449 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5450 } 5451 5452 l2cap_chan_unlock(chan); 5453 l2cap_chan_put(chan); 5454} 5455 5456static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid, 5457 u16 result) 5458{ 5459 struct l2cap_chan *chan; 5460 5461 chan = l2cap_get_chan_by_ident(conn, ident); 5462 if (!chan) { 5463 /* Could not locate channel, icid is best guess */ 5464 l2cap_send_move_chan_cfm_icid(conn, icid); 5465 return; 5466 } 5467 5468 __clear_chan_timer(chan); 5469 5470 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) { 5471 if (result == L2CAP_MR_COLLISION) { 5472 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER; 5473 } else { 5474 /* Cleanup - cancel move */ 5475 chan->move_id = chan->local_amp_id; 5476 l2cap_move_done(chan); 5477 } 5478 } 5479 5480 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5481 5482 l2cap_chan_unlock(chan); 5483 l2cap_chan_put(chan); 5484} 5485 5486static int l2cap_move_channel_rsp(struct l2cap_conn *conn, 5487 struct l2cap_cmd_hdr *cmd, 5488 u16 cmd_len, void *data) 5489{ 5490 struct l2cap_move_chan_rsp *rsp = data; 5491 u16 icid, result; 5492 5493 if (cmd_len != sizeof(*rsp)) 5494 return -EPROTO; 5495 5496 icid = le16_to_cpu(rsp->icid); 5497 result = le16_to_cpu(rsp->result); 5498 5499 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result); 5500 5501 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND) 5502 l2cap_move_continue(conn, icid, result); 5503 else 5504 l2cap_move_fail(conn, cmd->ident, icid, result); 5505 5506 return 0; 5507} 5508 5509static int l2cap_move_channel_confirm(struct l2cap_conn *conn, 5510 struct l2cap_cmd_hdr *cmd, 5511 u16 cmd_len, void *data) 5512{ 5513 struct l2cap_move_chan_cfm *cfm = data; 5514 struct l2cap_chan *chan; 5515 u16 icid, result; 5516 5517 if (cmd_len != sizeof(*cfm)) 5518 return -EPROTO; 5519 5520 icid = le16_to_cpu(cfm->icid); 5521 result = le16_to_cpu(cfm->result); 5522 5523 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result); 5524 5525 chan = l2cap_get_chan_by_dcid(conn, icid); 5526 if (!chan) { 5527 /* Spec requires a response even if the icid was not found */ 5528 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid); 5529 return 0; 5530 } 5531 5532 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) { 5533 if (result == L2CAP_MC_CONFIRMED) { 5534 chan->local_amp_id = chan->move_id; 5535 if (chan->local_amp_id == AMP_ID_BREDR) 5536 __release_logical_link(chan); 5537 } else { 5538 chan->move_id = chan->local_amp_id; 5539 } 5540 5541 l2cap_move_done(chan); 5542 } 5543 5544 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid); 5545 5546 l2cap_chan_unlock(chan); 5547 l2cap_chan_put(chan); 5548 5549 return 0; 5550} 5551 5552static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn, 5553 struct l2cap_cmd_hdr *cmd, 5554 u16 cmd_len, void *data) 5555{ 5556 struct l2cap_move_chan_cfm_rsp *rsp = data; 5557 struct l2cap_chan *chan; 5558 u16 icid; 5559 5560 if (cmd_len != sizeof(*rsp)) 5561 return -EPROTO; 5562 5563 icid = le16_to_cpu(rsp->icid); 5564 5565 BT_DBG("icid 0x%4.4x", icid); 5566 5567 chan = l2cap_get_chan_by_scid(conn, icid); 5568 if (!chan) 5569 return 0; 5570 5571 __clear_chan_timer(chan); 5572 5573 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) { 5574 chan->local_amp_id = chan->move_id; 5575 5576 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan) 5577 __release_logical_link(chan); 5578 5579 l2cap_move_done(chan); 5580 } 5581 5582 l2cap_chan_unlock(chan); 5583 l2cap_chan_put(chan); 5584 5585 return 0; 5586} 5587 5588static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn, 5589 struct l2cap_cmd_hdr *cmd, 5590 u16 cmd_len, u8 *data) 5591{ 5592 struct hci_conn *hcon = conn->hcon; 5593 struct l2cap_conn_param_update_req *req; 5594 struct l2cap_conn_param_update_rsp rsp; 5595 u16 min, max, latency, to_multiplier; 5596 int err; 5597 5598 if (hcon->role != HCI_ROLE_MASTER) 5599 return -EINVAL; 5600 5601 if (cmd_len != sizeof(struct l2cap_conn_param_update_req)) 5602 return -EPROTO; 5603 5604 req = (struct l2cap_conn_param_update_req *) data; 5605 min = __le16_to_cpu(req->min); 5606 max = __le16_to_cpu(req->max); 5607 latency = __le16_to_cpu(req->latency); 5608 to_multiplier = __le16_to_cpu(req->to_multiplier); 5609 5610 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x", 5611 min, max, latency, to_multiplier); 5612 5613 memset(&rsp, 0, sizeof(rsp)); 5614 5615 err = hci_check_conn_params(min, max, latency, to_multiplier); 5616 if (err) 5617 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED); 5618 else 5619 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED); 5620 5621 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP, 5622 sizeof(rsp), &rsp); 5623 5624 if (!err) { 5625 u8 store_hint; 5626 5627 store_hint = hci_le_conn_update(hcon, min, max, latency, 5628 to_multiplier); 5629 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type, 5630 store_hint, min, max, latency, 5631 to_multiplier); 5632 5633 } 5634 5635 return 0; 5636} 5637 5638static int l2cap_le_connect_rsp(struct l2cap_conn *conn, 5639 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5640 u8 *data) 5641{ 5642 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data; 5643 struct hci_conn *hcon = conn->hcon; 5644 u16 dcid, mtu, mps, credits, result; 5645 struct l2cap_chan *chan; 5646 int err, sec_level; 5647 5648 if (cmd_len < sizeof(*rsp)) 5649 return -EPROTO; 5650 5651 dcid = __le16_to_cpu(rsp->dcid); 5652 mtu = __le16_to_cpu(rsp->mtu); 5653 mps = __le16_to_cpu(rsp->mps); 5654 credits = __le16_to_cpu(rsp->credits); 5655 result = __le16_to_cpu(rsp->result); 5656 5657 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 || 5658 dcid < L2CAP_CID_DYN_START || 5659 dcid > L2CAP_CID_LE_DYN_END)) 5660 return -EPROTO; 5661 5662 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x", 5663 dcid, mtu, mps, credits, result); 5664 5665 mutex_lock(&conn->chan_lock); 5666 5667 chan = __l2cap_get_chan_by_ident(conn, cmd->ident); 5668 if (!chan) { 5669 err = -EBADSLT; 5670 goto unlock; 5671 } 5672 5673 err = 0; 5674 5675 l2cap_chan_lock(chan); 5676 5677 switch (result) { 5678 case L2CAP_CR_LE_SUCCESS: 5679 if (__l2cap_get_chan_by_dcid(conn, dcid)) { 5680 err = -EBADSLT; 5681 break; 5682 } 5683 5684 chan->ident = 0; 5685 chan->dcid = dcid; 5686 chan->omtu = mtu; 5687 chan->remote_mps = mps; 5688 chan->tx_credits = credits; 5689 l2cap_chan_ready(chan); 5690 break; 5691 5692 case L2CAP_CR_LE_AUTHENTICATION: 5693 case L2CAP_CR_LE_ENCRYPTION: 5694 /* If we already have MITM protection we can't do 5695 * anything. 5696 */ 5697 if (hcon->sec_level > BT_SECURITY_MEDIUM) { 5698 l2cap_chan_del(chan, ECONNREFUSED); 5699 break; 5700 } 5701 5702 sec_level = hcon->sec_level + 1; 5703 if (chan->sec_level < sec_level) 5704 chan->sec_level = sec_level; 5705 5706 /* We'll need to send a new Connect Request */ 5707 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags); 5708 5709 smp_conn_security(hcon, chan->sec_level); 5710 break; 5711 5712 default: 5713 l2cap_chan_del(chan, ECONNREFUSED); 5714 break; 5715 } 5716 5717 l2cap_chan_unlock(chan); 5718 5719unlock: 5720 mutex_unlock(&conn->chan_lock); 5721 5722 return err; 5723} 5724 5725static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn, 5726 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5727 u8 *data) 5728{ 5729 int err = 0; 5730 5731 switch (cmd->code) { 5732 case L2CAP_COMMAND_REJ: 5733 l2cap_command_rej(conn, cmd, cmd_len, data); 5734 break; 5735 5736 case L2CAP_CONN_REQ: 5737 err = l2cap_connect_req(conn, cmd, cmd_len, data); 5738 break; 5739 5740 case L2CAP_CONN_RSP: 5741 case L2CAP_CREATE_CHAN_RSP: 5742 l2cap_connect_create_rsp(conn, cmd, cmd_len, data); 5743 break; 5744 5745 case L2CAP_CONF_REQ: 5746 err = l2cap_config_req(conn, cmd, cmd_len, data); 5747 break; 5748 5749 case L2CAP_CONF_RSP: 5750 l2cap_config_rsp(conn, cmd, cmd_len, data); 5751 break; 5752 5753 case L2CAP_DISCONN_REQ: 5754 err = l2cap_disconnect_req(conn, cmd, cmd_len, data); 5755 break; 5756 5757 case L2CAP_DISCONN_RSP: 5758 l2cap_disconnect_rsp(conn, cmd, cmd_len, data); 5759 break; 5760 5761 case L2CAP_ECHO_REQ: 5762 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data); 5763 break; 5764 5765 case L2CAP_ECHO_RSP: 5766 break; 5767 5768 case L2CAP_INFO_REQ: 5769 err = l2cap_information_req(conn, cmd, cmd_len, data); 5770 break; 5771 5772 case L2CAP_INFO_RSP: 5773 l2cap_information_rsp(conn, cmd, cmd_len, data); 5774 break; 5775 5776 case L2CAP_CREATE_CHAN_REQ: 5777 err = l2cap_create_channel_req(conn, cmd, cmd_len, data); 5778 break; 5779 5780 case L2CAP_MOVE_CHAN_REQ: 5781 err = l2cap_move_channel_req(conn, cmd, cmd_len, data); 5782 break; 5783 5784 case L2CAP_MOVE_CHAN_RSP: 5785 l2cap_move_channel_rsp(conn, cmd, cmd_len, data); 5786 break; 5787 5788 case L2CAP_MOVE_CHAN_CFM: 5789 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data); 5790 break; 5791 5792 case L2CAP_MOVE_CHAN_CFM_RSP: 5793 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data); 5794 break; 5795 5796 default: 5797 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code); 5798 err = -EINVAL; 5799 break; 5800 } 5801 5802 return err; 5803} 5804 5805static int l2cap_le_connect_req(struct l2cap_conn *conn, 5806 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5807 u8 *data) 5808{ 5809 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data; 5810 struct l2cap_le_conn_rsp rsp; 5811 struct l2cap_chan *chan, *pchan; 5812 u16 dcid, scid, credits, mtu, mps; 5813 __le16 psm; 5814 u8 result; 5815 5816 if (cmd_len != sizeof(*req)) 5817 return -EPROTO; 5818 5819 scid = __le16_to_cpu(req->scid); 5820 mtu = __le16_to_cpu(req->mtu); 5821 mps = __le16_to_cpu(req->mps); 5822 psm = req->psm; 5823 dcid = 0; 5824 credits = 0; 5825 5826 if (mtu < 23 || mps < 23) 5827 return -EPROTO; 5828 5829 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm), 5830 scid, mtu, mps); 5831 5832 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A 5833 * page 1059: 5834 * 5835 * Valid range: 0x0001-0x00ff 5836 * 5837 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges 5838 */ 5839 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) { 5840 result = L2CAP_CR_LE_BAD_PSM; 5841 chan = NULL; 5842 goto response; 5843 } 5844 5845 /* Check if we have socket listening on psm */ 5846 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src, 5847 &conn->hcon->dst, LE_LINK); 5848 if (!pchan) { 5849 result = L2CAP_CR_LE_BAD_PSM; 5850 chan = NULL; 5851 goto response; 5852 } 5853 5854 mutex_lock(&conn->chan_lock); 5855 l2cap_chan_lock(pchan); 5856 5857 if (!smp_sufficient_security(conn->hcon, pchan->sec_level, 5858 SMP_ALLOW_STK)) { 5859 result = L2CAP_CR_LE_AUTHENTICATION; 5860 chan = NULL; 5861 goto response_unlock; 5862 } 5863 5864 /* Check for valid dynamic CID range */ 5865 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) { 5866 result = L2CAP_CR_LE_INVALID_SCID; 5867 chan = NULL; 5868 goto response_unlock; 5869 } 5870 5871 /* Check if we already have channel with that dcid */ 5872 if (__l2cap_get_chan_by_dcid(conn, scid)) { 5873 result = L2CAP_CR_LE_SCID_IN_USE; 5874 chan = NULL; 5875 goto response_unlock; 5876 } 5877 5878 chan = pchan->ops->new_connection(pchan); 5879 if (!chan) { 5880 result = L2CAP_CR_LE_NO_MEM; 5881 goto response_unlock; 5882 } 5883 5884 bacpy(&chan->src, &conn->hcon->src); 5885 bacpy(&chan->dst, &conn->hcon->dst); 5886 chan->src_type = bdaddr_src_type(conn->hcon); 5887 chan->dst_type = bdaddr_dst_type(conn->hcon); 5888 chan->psm = psm; 5889 chan->dcid = scid; 5890 chan->omtu = mtu; 5891 chan->remote_mps = mps; 5892 5893 __l2cap_chan_add(conn, chan); 5894 5895 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits)); 5896 5897 dcid = chan->scid; 5898 credits = chan->rx_credits; 5899 5900 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 5901 5902 chan->ident = cmd->ident; 5903 5904 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 5905 l2cap_state_change(chan, BT_CONNECT2); 5906 /* The following result value is actually not defined 5907 * for LE CoC but we use it to let the function know 5908 * that it should bail out after doing its cleanup 5909 * instead of sending a response. 5910 */ 5911 result = L2CAP_CR_PEND; 5912 chan->ops->defer(chan); 5913 } else { 5914 l2cap_chan_ready(chan); 5915 result = L2CAP_CR_LE_SUCCESS; 5916 } 5917 5918response_unlock: 5919 l2cap_chan_unlock(pchan); 5920 mutex_unlock(&conn->chan_lock); 5921 l2cap_chan_put(pchan); 5922 5923 if (result == L2CAP_CR_PEND) 5924 return 0; 5925 5926response: 5927 if (chan) { 5928 rsp.mtu = cpu_to_le16(chan->imtu); 5929 rsp.mps = cpu_to_le16(chan->mps); 5930 } else { 5931 rsp.mtu = 0; 5932 rsp.mps = 0; 5933 } 5934 5935 rsp.dcid = cpu_to_le16(dcid); 5936 rsp.credits = cpu_to_le16(credits); 5937 rsp.result = cpu_to_le16(result); 5938 5939 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp); 5940 5941 return 0; 5942} 5943 5944static inline int l2cap_le_credits(struct l2cap_conn *conn, 5945 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5946 u8 *data) 5947{ 5948 struct l2cap_le_credits *pkt; 5949 struct l2cap_chan *chan; 5950 u16 cid, credits, max_credits; 5951 5952 if (cmd_len != sizeof(*pkt)) 5953 return -EPROTO; 5954 5955 pkt = (struct l2cap_le_credits *) data; 5956 cid = __le16_to_cpu(pkt->cid); 5957 credits = __le16_to_cpu(pkt->credits); 5958 5959 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits); 5960 5961 chan = l2cap_get_chan_by_dcid(conn, cid); 5962 if (!chan) 5963 return -EBADSLT; 5964 5965 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits; 5966 if (credits > max_credits) { 5967 BT_ERR("LE credits overflow"); 5968 l2cap_send_disconn_req(chan, ECONNRESET); 5969 5970 /* Return 0 so that we don't trigger an unnecessary 5971 * command reject packet. 5972 */ 5973 goto unlock; 5974 } 5975 5976 chan->tx_credits += credits; 5977 5978 /* Resume sending */ 5979 l2cap_le_flowctl_send(chan); 5980 5981 if (chan->tx_credits) 5982 chan->ops->resume(chan); 5983 5984unlock: 5985 l2cap_chan_unlock(chan); 5986 l2cap_chan_put(chan); 5987 5988 return 0; 5989} 5990 5991static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, 5992 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5993 u8 *data) 5994{ 5995 struct l2cap_ecred_conn_req *req = (void *) data; 5996 struct { 5997 struct l2cap_ecred_conn_rsp rsp; 5998 __le16 dcid[L2CAP_ECRED_MAX_CID]; 5999 } __packed pdu; 6000 struct l2cap_chan *chan, *pchan; 6001 u16 mtu, mps; 6002 __le16 psm; 6003 u8 result, len = 0; 6004 int i, num_scid; 6005 bool defer = false; 6006 6007 if (!enable_ecred) 6008 return -EINVAL; 6009 6010 if (cmd_len < sizeof(*req) || (cmd_len - sizeof(*req)) % sizeof(u16)) { 6011 result = L2CAP_CR_LE_INVALID_PARAMS; 6012 goto response; 6013 } 6014 6015 cmd_len -= sizeof(*req); 6016 num_scid = cmd_len / sizeof(u16); 6017 6018 if (num_scid > ARRAY_SIZE(pdu.dcid)) { 6019 result = L2CAP_CR_LE_INVALID_PARAMS; 6020 goto response; 6021 } 6022 6023 mtu = __le16_to_cpu(req->mtu); 6024 mps = __le16_to_cpu(req->mps); 6025 6026 if (mtu < L2CAP_ECRED_MIN_MTU || mps < L2CAP_ECRED_MIN_MPS) { 6027 result = L2CAP_CR_LE_UNACCEPT_PARAMS; 6028 goto response; 6029 } 6030 6031 psm = req->psm; 6032 6033 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A 6034 * page 1059: 6035 * 6036 * Valid range: 0x0001-0x00ff 6037 * 6038 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges 6039 */ 6040 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) { 6041 result = L2CAP_CR_LE_BAD_PSM; 6042 goto response; 6043 } 6044 6045 BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps); 6046 6047 memset(&pdu, 0, sizeof(pdu)); 6048 6049 /* Check if we have socket listening on psm */ 6050 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src, 6051 &conn->hcon->dst, LE_LINK); 6052 if (!pchan) { 6053 result = L2CAP_CR_LE_BAD_PSM; 6054 goto response; 6055 } 6056 6057 mutex_lock(&conn->chan_lock); 6058 l2cap_chan_lock(pchan); 6059 6060 if (!smp_sufficient_security(conn->hcon, pchan->sec_level, 6061 SMP_ALLOW_STK)) { 6062 result = L2CAP_CR_LE_AUTHENTICATION; 6063 goto unlock; 6064 } 6065 6066 result = L2CAP_CR_LE_SUCCESS; 6067 6068 for (i = 0; i < num_scid; i++) { 6069 u16 scid = __le16_to_cpu(req->scid[i]); 6070 6071 BT_DBG("scid[%d] 0x%4.4x", i, scid); 6072 6073 pdu.dcid[i] = 0x0000; 6074 len += sizeof(*pdu.dcid); 6075 6076 /* Check for valid dynamic CID range */ 6077 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) { 6078 result = L2CAP_CR_LE_INVALID_SCID; 6079 continue; 6080 } 6081 6082 /* Check if we already have channel with that dcid */ 6083 if (__l2cap_get_chan_by_dcid(conn, scid)) { 6084 result = L2CAP_CR_LE_SCID_IN_USE; 6085 continue; 6086 } 6087 6088 chan = pchan->ops->new_connection(pchan); 6089 if (!chan) { 6090 result = L2CAP_CR_LE_NO_MEM; 6091 continue; 6092 } 6093 6094 bacpy(&chan->src, &conn->hcon->src); 6095 bacpy(&chan->dst, &conn->hcon->dst); 6096 chan->src_type = bdaddr_src_type(conn->hcon); 6097 chan->dst_type = bdaddr_dst_type(conn->hcon); 6098 chan->psm = psm; 6099 chan->dcid = scid; 6100 chan->omtu = mtu; 6101 chan->remote_mps = mps; 6102 6103 __l2cap_chan_add(conn, chan); 6104 6105 l2cap_ecred_init(chan, __le16_to_cpu(req->credits)); 6106 6107 /* Init response */ 6108 if (!pdu.rsp.credits) { 6109 pdu.rsp.mtu = cpu_to_le16(chan->imtu); 6110 pdu.rsp.mps = cpu_to_le16(chan->mps); 6111 pdu.rsp.credits = cpu_to_le16(chan->rx_credits); 6112 } 6113 6114 pdu.dcid[i] = cpu_to_le16(chan->scid); 6115 6116 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 6117 6118 chan->ident = cmd->ident; 6119 chan->mode = L2CAP_MODE_EXT_FLOWCTL; 6120 6121 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 6122 l2cap_state_change(chan, BT_CONNECT2); 6123 defer = true; 6124 chan->ops->defer(chan); 6125 } else { 6126 l2cap_chan_ready(chan); 6127 } 6128 } 6129 6130unlock: 6131 l2cap_chan_unlock(pchan); 6132 mutex_unlock(&conn->chan_lock); 6133 l2cap_chan_put(pchan); 6134 6135response: 6136 pdu.rsp.result = cpu_to_le16(result); 6137 6138 if (defer) 6139 return 0; 6140 6141 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_CONN_RSP, 6142 sizeof(pdu.rsp) + len, &pdu); 6143 6144 return 0; 6145} 6146 6147static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn, 6148 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6149 u8 *data) 6150{ 6151 struct l2cap_ecred_conn_rsp *rsp = (void *) data; 6152 struct hci_conn *hcon = conn->hcon; 6153 u16 mtu, mps, credits, result; 6154 struct l2cap_chan *chan, *tmp; 6155 int err = 0, sec_level; 6156 int i = 0; 6157 6158 if (cmd_len < sizeof(*rsp)) 6159 return -EPROTO; 6160 6161 mtu = __le16_to_cpu(rsp->mtu); 6162 mps = __le16_to_cpu(rsp->mps); 6163 credits = __le16_to_cpu(rsp->credits); 6164 result = __le16_to_cpu(rsp->result); 6165 6166 BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits, 6167 result); 6168 6169 mutex_lock(&conn->chan_lock); 6170 6171 cmd_len -= sizeof(*rsp); 6172 6173 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { 6174 u16 dcid; 6175 6176 if (chan->ident != cmd->ident || 6177 chan->mode != L2CAP_MODE_EXT_FLOWCTL || 6178 chan->state == BT_CONNECTED) 6179 continue; 6180 6181 l2cap_chan_lock(chan); 6182 6183 /* Check that there is a dcid for each pending channel */ 6184 if (cmd_len < sizeof(dcid)) { 6185 l2cap_chan_del(chan, ECONNREFUSED); 6186 l2cap_chan_unlock(chan); 6187 continue; 6188 } 6189 6190 dcid = __le16_to_cpu(rsp->dcid[i++]); 6191 cmd_len -= sizeof(u16); 6192 6193 BT_DBG("dcid[%d] 0x%4.4x", i, dcid); 6194 6195 /* Check if dcid is already in use */ 6196 if (dcid && __l2cap_get_chan_by_dcid(conn, dcid)) { 6197 /* If a device receives a 6198 * L2CAP_CREDIT_BASED_CONNECTION_RSP packet with an 6199 * already-assigned Destination CID, then both the 6200 * original channel and the new channel shall be 6201 * immediately discarded and not used. 6202 */ 6203 l2cap_chan_del(chan, ECONNREFUSED); 6204 l2cap_chan_unlock(chan); 6205 chan = __l2cap_get_chan_by_dcid(conn, dcid); 6206 l2cap_chan_lock(chan); 6207 l2cap_chan_del(chan, ECONNRESET); 6208 l2cap_chan_unlock(chan); 6209 continue; 6210 } 6211 6212 switch (result) { 6213 case L2CAP_CR_LE_AUTHENTICATION: 6214 case L2CAP_CR_LE_ENCRYPTION: 6215 /* If we already have MITM protection we can't do 6216 * anything. 6217 */ 6218 if (hcon->sec_level > BT_SECURITY_MEDIUM) { 6219 l2cap_chan_del(chan, ECONNREFUSED); 6220 break; 6221 } 6222 6223 sec_level = hcon->sec_level + 1; 6224 if (chan->sec_level < sec_level) 6225 chan->sec_level = sec_level; 6226 6227 /* We'll need to send a new Connect Request */ 6228 clear_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags); 6229 6230 smp_conn_security(hcon, chan->sec_level); 6231 break; 6232 6233 case L2CAP_CR_LE_BAD_PSM: 6234 l2cap_chan_del(chan, ECONNREFUSED); 6235 break; 6236 6237 default: 6238 /* If dcid was not set it means channels was refused */ 6239 if (!dcid) { 6240 l2cap_chan_del(chan, ECONNREFUSED); 6241 break; 6242 } 6243 6244 chan->ident = 0; 6245 chan->dcid = dcid; 6246 chan->omtu = mtu; 6247 chan->remote_mps = mps; 6248 chan->tx_credits = credits; 6249 l2cap_chan_ready(chan); 6250 break; 6251 } 6252 6253 l2cap_chan_unlock(chan); 6254 } 6255 6256 mutex_unlock(&conn->chan_lock); 6257 6258 return err; 6259} 6260 6261static inline int l2cap_ecred_reconf_req(struct l2cap_conn *conn, 6262 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6263 u8 *data) 6264{ 6265 struct l2cap_ecred_reconf_req *req = (void *) data; 6266 struct l2cap_ecred_reconf_rsp rsp; 6267 u16 mtu, mps, result; 6268 struct l2cap_chan *chan; 6269 int i, num_scid; 6270 6271 if (!enable_ecred) 6272 return -EINVAL; 6273 6274 if (cmd_len < sizeof(*req) || cmd_len - sizeof(*req) % sizeof(u16)) { 6275 result = L2CAP_CR_LE_INVALID_PARAMS; 6276 goto respond; 6277 } 6278 6279 mtu = __le16_to_cpu(req->mtu); 6280 mps = __le16_to_cpu(req->mps); 6281 6282 BT_DBG("mtu %u mps %u", mtu, mps); 6283 6284 if (mtu < L2CAP_ECRED_MIN_MTU) { 6285 result = L2CAP_RECONF_INVALID_MTU; 6286 goto respond; 6287 } 6288 6289 if (mps < L2CAP_ECRED_MIN_MPS) { 6290 result = L2CAP_RECONF_INVALID_MPS; 6291 goto respond; 6292 } 6293 6294 cmd_len -= sizeof(*req); 6295 num_scid = cmd_len / sizeof(u16); 6296 result = L2CAP_RECONF_SUCCESS; 6297 6298 for (i = 0; i < num_scid; i++) { 6299 u16 scid; 6300 6301 scid = __le16_to_cpu(req->scid[i]); 6302 if (!scid) 6303 return -EPROTO; 6304 6305 chan = __l2cap_get_chan_by_dcid(conn, scid); 6306 if (!chan) 6307 continue; 6308 6309 /* If the MTU value is decreased for any of the included 6310 * channels, then the receiver shall disconnect all 6311 * included channels. 6312 */ 6313 if (chan->omtu > mtu) { 6314 BT_ERR("chan %p decreased MTU %u -> %u", chan, 6315 chan->omtu, mtu); 6316 result = L2CAP_RECONF_INVALID_MTU; 6317 } 6318 6319 chan->omtu = mtu; 6320 chan->remote_mps = mps; 6321 } 6322 6323respond: 6324 rsp.result = cpu_to_le16(result); 6325 6326 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_RECONF_RSP, sizeof(rsp), 6327 &rsp); 6328 6329 return 0; 6330} 6331 6332static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn, 6333 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6334 u8 *data) 6335{ 6336 struct l2cap_chan *chan, *tmp; 6337 struct l2cap_ecred_conn_rsp *rsp = (void *) data; 6338 u16 result; 6339 6340 if (cmd_len < sizeof(*rsp)) 6341 return -EPROTO; 6342 6343 result = __le16_to_cpu(rsp->result); 6344 6345 BT_DBG("result 0x%4.4x", rsp->result); 6346 6347 if (!result) 6348 return 0; 6349 6350 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { 6351 if (chan->ident != cmd->ident) 6352 continue; 6353 6354 l2cap_chan_del(chan, ECONNRESET); 6355 } 6356 6357 return 0; 6358} 6359 6360static inline int l2cap_le_command_rej(struct l2cap_conn *conn, 6361 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6362 u8 *data) 6363{ 6364 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data; 6365 struct l2cap_chan *chan; 6366 6367 if (cmd_len < sizeof(*rej)) 6368 return -EPROTO; 6369 6370 mutex_lock(&conn->chan_lock); 6371 6372 chan = __l2cap_get_chan_by_ident(conn, cmd->ident); 6373 if (!chan) 6374 goto done; 6375 6376 chan = l2cap_chan_hold_unless_zero(chan); 6377 if (!chan) 6378 goto done; 6379 6380 l2cap_chan_lock(chan); 6381 l2cap_chan_del(chan, ECONNREFUSED); 6382 l2cap_chan_unlock(chan); 6383 l2cap_chan_put(chan); 6384 6385done: 6386 mutex_unlock(&conn->chan_lock); 6387 return 0; 6388} 6389 6390static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn, 6391 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6392 u8 *data) 6393{ 6394 int err = 0; 6395 6396 switch (cmd->code) { 6397 case L2CAP_COMMAND_REJ: 6398 l2cap_le_command_rej(conn, cmd, cmd_len, data); 6399 break; 6400 6401 case L2CAP_CONN_PARAM_UPDATE_REQ: 6402 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data); 6403 break; 6404 6405 case L2CAP_CONN_PARAM_UPDATE_RSP: 6406 break; 6407 6408 case L2CAP_LE_CONN_RSP: 6409 l2cap_le_connect_rsp(conn, cmd, cmd_len, data); 6410 break; 6411 6412 case L2CAP_LE_CONN_REQ: 6413 err = l2cap_le_connect_req(conn, cmd, cmd_len, data); 6414 break; 6415 6416 case L2CAP_LE_CREDITS: 6417 err = l2cap_le_credits(conn, cmd, cmd_len, data); 6418 break; 6419 6420 case L2CAP_ECRED_CONN_REQ: 6421 err = l2cap_ecred_conn_req(conn, cmd, cmd_len, data); 6422 break; 6423 6424 case L2CAP_ECRED_CONN_RSP: 6425 err = l2cap_ecred_conn_rsp(conn, cmd, cmd_len, data); 6426 break; 6427 6428 case L2CAP_ECRED_RECONF_REQ: 6429 err = l2cap_ecred_reconf_req(conn, cmd, cmd_len, data); 6430 break; 6431 6432 case L2CAP_ECRED_RECONF_RSP: 6433 err = l2cap_ecred_reconf_rsp(conn, cmd, cmd_len, data); 6434 break; 6435 6436 case L2CAP_DISCONN_REQ: 6437 err = l2cap_disconnect_req(conn, cmd, cmd_len, data); 6438 break; 6439 6440 case L2CAP_DISCONN_RSP: 6441 l2cap_disconnect_rsp(conn, cmd, cmd_len, data); 6442 break; 6443 6444 default: 6445 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code); 6446 err = -EINVAL; 6447 break; 6448 } 6449 6450 return err; 6451} 6452 6453static inline void l2cap_le_sig_channel(struct l2cap_conn *conn, 6454 struct sk_buff *skb) 6455{ 6456 struct hci_conn *hcon = conn->hcon; 6457 struct l2cap_cmd_hdr *cmd; 6458 u16 len; 6459 int err; 6460 6461 if (hcon->type != LE_LINK) 6462 goto drop; 6463 6464 if (skb->len < L2CAP_CMD_HDR_SIZE) 6465 goto drop; 6466 6467 cmd = (void *) skb->data; 6468 skb_pull(skb, L2CAP_CMD_HDR_SIZE); 6469 6470 len = le16_to_cpu(cmd->len); 6471 6472 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident); 6473 6474 if (len != skb->len || !cmd->ident) { 6475 BT_DBG("corrupted command"); 6476 goto drop; 6477 } 6478 6479 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data); 6480 if (err) { 6481 struct l2cap_cmd_rej_unk rej; 6482 6483 BT_ERR("Wrong link type (%d)", err); 6484 6485 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD); 6486 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ, 6487 sizeof(rej), &rej); 6488 } 6489 6490drop: 6491 kfree_skb(skb); 6492} 6493 6494static inline void l2cap_sig_send_rej(struct l2cap_conn *conn, u16 ident) 6495{ 6496 struct l2cap_cmd_rej_unk rej; 6497 6498 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD); 6499 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej); 6500} 6501 6502static inline void l2cap_sig_channel(struct l2cap_conn *conn, 6503 struct sk_buff *skb) 6504{ 6505 struct hci_conn *hcon = conn->hcon; 6506 struct l2cap_cmd_hdr *cmd; 6507 int err; 6508 6509 l2cap_raw_recv(conn, skb); 6510 6511 if (hcon->type != ACL_LINK) 6512 goto drop; 6513 6514 while (skb->len >= L2CAP_CMD_HDR_SIZE) { 6515 u16 len; 6516 6517 cmd = (void *) skb->data; 6518 skb_pull(skb, L2CAP_CMD_HDR_SIZE); 6519 6520 len = le16_to_cpu(cmd->len); 6521 6522 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, 6523 cmd->ident); 6524 6525 if (len > skb->len || !cmd->ident) { 6526 BT_DBG("corrupted command"); 6527 l2cap_sig_send_rej(conn, cmd->ident); 6528 skb_pull(skb, len > skb->len ? skb->len : len); 6529 continue; 6530 } 6531 6532 err = l2cap_bredr_sig_cmd(conn, cmd, len, skb->data); 6533 if (err) { 6534 BT_ERR("Wrong link type (%d)", err); 6535 l2cap_sig_send_rej(conn, cmd->ident); 6536 } 6537 6538 skb_pull(skb, len); 6539 } 6540 6541 if (skb->len > 0) { 6542 BT_DBG("corrupted command"); 6543 l2cap_sig_send_rej(conn, 0); 6544 } 6545 6546drop: 6547 kfree_skb(skb); 6548} 6549 6550static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb) 6551{ 6552 u16 our_fcs, rcv_fcs; 6553 int hdr_size; 6554 6555 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 6556 hdr_size = L2CAP_EXT_HDR_SIZE; 6557 else 6558 hdr_size = L2CAP_ENH_HDR_SIZE; 6559 6560 if (chan->fcs == L2CAP_FCS_CRC16) { 6561 skb_trim(skb, skb->len - L2CAP_FCS_SIZE); 6562 rcv_fcs = get_unaligned_le16(skb->data + skb->len); 6563 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size); 6564 6565 if (our_fcs != rcv_fcs) 6566 return -EBADMSG; 6567 } 6568 return 0; 6569} 6570 6571static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan) 6572{ 6573 struct l2cap_ctrl control; 6574 6575 BT_DBG("chan %p", chan); 6576 6577 memset(&control, 0, sizeof(control)); 6578 control.sframe = 1; 6579 control.final = 1; 6580 control.reqseq = chan->buffer_seq; 6581 set_bit(CONN_SEND_FBIT, &chan->conn_state); 6582 6583 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 6584 control.super = L2CAP_SUPER_RNR; 6585 l2cap_send_sframe(chan, &control); 6586 } 6587 6588 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) && 6589 chan->unacked_frames > 0) 6590 __set_retrans_timer(chan); 6591 6592 /* Send pending iframes */ 6593 l2cap_ertm_send(chan); 6594 6595 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) && 6596 test_bit(CONN_SEND_FBIT, &chan->conn_state)) { 6597 /* F-bit wasn't sent in an s-frame or i-frame yet, so 6598 * send it now. 6599 */ 6600 control.super = L2CAP_SUPER_RR; 6601 l2cap_send_sframe(chan, &control); 6602 } 6603} 6604 6605static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag, 6606 struct sk_buff **last_frag) 6607{ 6608 /* skb->len reflects data in skb as well as all fragments 6609 * skb->data_len reflects only data in fragments 6610 */ 6611 if (!skb_has_frag_list(skb)) 6612 skb_shinfo(skb)->frag_list = new_frag; 6613 6614 new_frag->next = NULL; 6615 6616 (*last_frag)->next = new_frag; 6617 *last_frag = new_frag; 6618 6619 skb->len += new_frag->len; 6620 skb->data_len += new_frag->len; 6621 skb->truesize += new_frag->truesize; 6622} 6623 6624static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, 6625 struct l2cap_ctrl *control) 6626{ 6627 int err = -EINVAL; 6628 6629 switch (control->sar) { 6630 case L2CAP_SAR_UNSEGMENTED: 6631 if (chan->sdu) 6632 break; 6633 6634 err = chan->ops->recv(chan, skb); 6635 break; 6636 6637 case L2CAP_SAR_START: 6638 if (chan->sdu) 6639 break; 6640 6641 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE)) 6642 break; 6643 6644 chan->sdu_len = get_unaligned_le16(skb->data); 6645 skb_pull(skb, L2CAP_SDULEN_SIZE); 6646 6647 if (chan->sdu_len > chan->imtu) { 6648 err = -EMSGSIZE; 6649 break; 6650 } 6651 6652 if (skb->len >= chan->sdu_len) 6653 break; 6654 6655 chan->sdu = skb; 6656 chan->sdu_last_frag = skb; 6657 6658 skb = NULL; 6659 err = 0; 6660 break; 6661 6662 case L2CAP_SAR_CONTINUE: 6663 if (!chan->sdu) 6664 break; 6665 6666 append_skb_frag(chan->sdu, skb, 6667 &chan->sdu_last_frag); 6668 skb = NULL; 6669 6670 if (chan->sdu->len >= chan->sdu_len) 6671 break; 6672 6673 err = 0; 6674 break; 6675 6676 case L2CAP_SAR_END: 6677 if (!chan->sdu) 6678 break; 6679 6680 append_skb_frag(chan->sdu, skb, 6681 &chan->sdu_last_frag); 6682 skb = NULL; 6683 6684 if (chan->sdu->len != chan->sdu_len) 6685 break; 6686 6687 err = chan->ops->recv(chan, chan->sdu); 6688 6689 if (!err) { 6690 /* Reassembly complete */ 6691 chan->sdu = NULL; 6692 chan->sdu_last_frag = NULL; 6693 chan->sdu_len = 0; 6694 } 6695 break; 6696 } 6697 6698 if (err) { 6699 kfree_skb(skb); 6700 kfree_skb(chan->sdu); 6701 chan->sdu = NULL; 6702 chan->sdu_last_frag = NULL; 6703 chan->sdu_len = 0; 6704 } 6705 6706 return err; 6707} 6708 6709static int l2cap_resegment(struct l2cap_chan *chan) 6710{ 6711 /* Placeholder */ 6712 return 0; 6713} 6714 6715void l2cap_chan_busy(struct l2cap_chan *chan, int busy) 6716{ 6717 u8 event; 6718 6719 if (chan->mode != L2CAP_MODE_ERTM) 6720 return; 6721 6722 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR; 6723 l2cap_tx(chan, NULL, NULL, event); 6724} 6725 6726static int l2cap_rx_queued_iframes(struct l2cap_chan *chan) 6727{ 6728 int err = 0; 6729 /* Pass sequential frames to l2cap_reassemble_sdu() 6730 * until a gap is encountered. 6731 */ 6732 6733 BT_DBG("chan %p", chan); 6734 6735 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 6736 struct sk_buff *skb; 6737 BT_DBG("Searching for skb with txseq %d (queue len %d)", 6738 chan->buffer_seq, skb_queue_len(&chan->srej_q)); 6739 6740 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq); 6741 6742 if (!skb) 6743 break; 6744 6745 skb_unlink(skb, &chan->srej_q); 6746 chan->buffer_seq = __next_seq(chan, chan->buffer_seq); 6747 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap); 6748 if (err) 6749 break; 6750 } 6751 6752 if (skb_queue_empty(&chan->srej_q)) { 6753 chan->rx_state = L2CAP_RX_STATE_RECV; 6754 l2cap_send_ack(chan); 6755 } 6756 6757 return err; 6758} 6759 6760static void l2cap_handle_srej(struct l2cap_chan *chan, 6761 struct l2cap_ctrl *control) 6762{ 6763 struct sk_buff *skb; 6764 6765 BT_DBG("chan %p, control %p", chan, control); 6766 6767 if (control->reqseq == chan->next_tx_seq) { 6768 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq); 6769 l2cap_send_disconn_req(chan, ECONNRESET); 6770 return; 6771 } 6772 6773 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq); 6774 6775 if (skb == NULL) { 6776 BT_DBG("Seq %d not available for retransmission", 6777 control->reqseq); 6778 return; 6779 } 6780 6781 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) { 6782 BT_DBG("Retry limit exceeded (%d)", chan->max_tx); 6783 l2cap_send_disconn_req(chan, ECONNRESET); 6784 return; 6785 } 6786 6787 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 6788 6789 if (control->poll) { 6790 l2cap_pass_to_tx(chan, control); 6791 6792 set_bit(CONN_SEND_FBIT, &chan->conn_state); 6793 l2cap_retransmit(chan, control); 6794 l2cap_ertm_send(chan); 6795 6796 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) { 6797 set_bit(CONN_SREJ_ACT, &chan->conn_state); 6798 chan->srej_save_reqseq = control->reqseq; 6799 } 6800 } else { 6801 l2cap_pass_to_tx_fbit(chan, control); 6802 6803 if (control->final) { 6804 if (chan->srej_save_reqseq != control->reqseq || 6805 !test_and_clear_bit(CONN_SREJ_ACT, 6806 &chan->conn_state)) 6807 l2cap_retransmit(chan, control); 6808 } else { 6809 l2cap_retransmit(chan, control); 6810 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) { 6811 set_bit(CONN_SREJ_ACT, &chan->conn_state); 6812 chan->srej_save_reqseq = control->reqseq; 6813 } 6814 } 6815 } 6816} 6817 6818static void l2cap_handle_rej(struct l2cap_chan *chan, 6819 struct l2cap_ctrl *control) 6820{ 6821 struct sk_buff *skb; 6822 6823 BT_DBG("chan %p, control %p", chan, control); 6824 6825 if (control->reqseq == chan->next_tx_seq) { 6826 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq); 6827 l2cap_send_disconn_req(chan, ECONNRESET); 6828 return; 6829 } 6830 6831 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq); 6832 6833 if (chan->max_tx && skb && 6834 bt_cb(skb)->l2cap.retries >= chan->max_tx) { 6835 BT_DBG("Retry limit exceeded (%d)", chan->max_tx); 6836 l2cap_send_disconn_req(chan, ECONNRESET); 6837 return; 6838 } 6839 6840 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 6841 6842 l2cap_pass_to_tx(chan, control); 6843 6844 if (control->final) { 6845 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state)) 6846 l2cap_retransmit_all(chan, control); 6847 } else { 6848 l2cap_retransmit_all(chan, control); 6849 l2cap_ertm_send(chan); 6850 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) 6851 set_bit(CONN_REJ_ACT, &chan->conn_state); 6852 } 6853} 6854 6855static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq) 6856{ 6857 BT_DBG("chan %p, txseq %d", chan, txseq); 6858 6859 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq, 6860 chan->expected_tx_seq); 6861 6862 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) { 6863 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= 6864 chan->tx_win) { 6865 /* See notes below regarding "double poll" and 6866 * invalid packets. 6867 */ 6868 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) { 6869 BT_DBG("Invalid/Ignore - after SREJ"); 6870 return L2CAP_TXSEQ_INVALID_IGNORE; 6871 } else { 6872 BT_DBG("Invalid - in window after SREJ sent"); 6873 return L2CAP_TXSEQ_INVALID; 6874 } 6875 } 6876 6877 if (chan->srej_list.head == txseq) { 6878 BT_DBG("Expected SREJ"); 6879 return L2CAP_TXSEQ_EXPECTED_SREJ; 6880 } 6881 6882 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) { 6883 BT_DBG("Duplicate SREJ - txseq already stored"); 6884 return L2CAP_TXSEQ_DUPLICATE_SREJ; 6885 } 6886 6887 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) { 6888 BT_DBG("Unexpected SREJ - not requested"); 6889 return L2CAP_TXSEQ_UNEXPECTED_SREJ; 6890 } 6891 } 6892 6893 if (chan->expected_tx_seq == txseq) { 6894 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= 6895 chan->tx_win) { 6896 BT_DBG("Invalid - txseq outside tx window"); 6897 return L2CAP_TXSEQ_INVALID; 6898 } else { 6899 BT_DBG("Expected"); 6900 return L2CAP_TXSEQ_EXPECTED; 6901 } 6902 } 6903 6904 if (__seq_offset(chan, txseq, chan->last_acked_seq) < 6905 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) { 6906 BT_DBG("Duplicate - expected_tx_seq later than txseq"); 6907 return L2CAP_TXSEQ_DUPLICATE; 6908 } 6909 6910 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) { 6911 /* A source of invalid packets is a "double poll" condition, 6912 * where delays cause us to send multiple poll packets. If 6913 * the remote stack receives and processes both polls, 6914 * sequence numbers can wrap around in such a way that a 6915 * resent frame has a sequence number that looks like new data 6916 * with a sequence gap. This would trigger an erroneous SREJ 6917 * request. 6918 * 6919 * Fortunately, this is impossible with a tx window that's 6920 * less than half of the maximum sequence number, which allows 6921 * invalid frames to be safely ignored. 6922 * 6923 * With tx window sizes greater than half of the tx window 6924 * maximum, the frame is invalid and cannot be ignored. This 6925 * causes a disconnect. 6926 */ 6927 6928 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) { 6929 BT_DBG("Invalid/Ignore - txseq outside tx window"); 6930 return L2CAP_TXSEQ_INVALID_IGNORE; 6931 } else { 6932 BT_DBG("Invalid - txseq outside tx window"); 6933 return L2CAP_TXSEQ_INVALID; 6934 } 6935 } else { 6936 BT_DBG("Unexpected - txseq indicates missing frames"); 6937 return L2CAP_TXSEQ_UNEXPECTED; 6938 } 6939} 6940 6941static int l2cap_rx_state_recv(struct l2cap_chan *chan, 6942 struct l2cap_ctrl *control, 6943 struct sk_buff *skb, u8 event) 6944{ 6945 struct l2cap_ctrl local_control; 6946 int err = 0; 6947 bool skb_in_use = false; 6948 6949 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb, 6950 event); 6951 6952 switch (event) { 6953 case L2CAP_EV_RECV_IFRAME: 6954 switch (l2cap_classify_txseq(chan, control->txseq)) { 6955 case L2CAP_TXSEQ_EXPECTED: 6956 l2cap_pass_to_tx(chan, control); 6957 6958 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 6959 BT_DBG("Busy, discarding expected seq %d", 6960 control->txseq); 6961 break; 6962 } 6963 6964 chan->expected_tx_seq = __next_seq(chan, 6965 control->txseq); 6966 6967 chan->buffer_seq = chan->expected_tx_seq; 6968 skb_in_use = true; 6969 6970 /* l2cap_reassemble_sdu may free skb, hence invalidate 6971 * control, so make a copy in advance to use it after 6972 * l2cap_reassemble_sdu returns and to avoid the race 6973 * condition, for example: 6974 * 6975 * The current thread calls: 6976 * l2cap_reassemble_sdu 6977 * chan->ops->recv == l2cap_sock_recv_cb 6978 * __sock_queue_rcv_skb 6979 * Another thread calls: 6980 * bt_sock_recvmsg 6981 * skb_recv_datagram 6982 * skb_free_datagram 6983 * Then the current thread tries to access control, but 6984 * it was freed by skb_free_datagram. 6985 */ 6986 local_control = *control; 6987 err = l2cap_reassemble_sdu(chan, skb, control); 6988 if (err) 6989 break; 6990 6991 if (local_control.final) { 6992 if (!test_and_clear_bit(CONN_REJ_ACT, 6993 &chan->conn_state)) { 6994 local_control.final = 0; 6995 l2cap_retransmit_all(chan, &local_control); 6996 l2cap_ertm_send(chan); 6997 } 6998 } 6999 7000 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) 7001 l2cap_send_ack(chan); 7002 break; 7003 case L2CAP_TXSEQ_UNEXPECTED: 7004 l2cap_pass_to_tx(chan, control); 7005 7006 /* Can't issue SREJ frames in the local busy state. 7007 * Drop this frame, it will be seen as missing 7008 * when local busy is exited. 7009 */ 7010 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 7011 BT_DBG("Busy, discarding unexpected seq %d", 7012 control->txseq); 7013 break; 7014 } 7015 7016 /* There was a gap in the sequence, so an SREJ 7017 * must be sent for each missing frame. The 7018 * current frame is stored for later use. 7019 */ 7020 skb_queue_tail(&chan->srej_q, skb); 7021 skb_in_use = true; 7022 BT_DBG("Queued %p (queue len %d)", skb, 7023 skb_queue_len(&chan->srej_q)); 7024 7025 clear_bit(CONN_SREJ_ACT, &chan->conn_state); 7026 l2cap_seq_list_clear(&chan->srej_list); 7027 l2cap_send_srej(chan, control->txseq); 7028 7029 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT; 7030 break; 7031 case L2CAP_TXSEQ_DUPLICATE: 7032 l2cap_pass_to_tx(chan, control); 7033 break; 7034 case L2CAP_TXSEQ_INVALID_IGNORE: 7035 break; 7036 case L2CAP_TXSEQ_INVALID: 7037 default: 7038 l2cap_send_disconn_req(chan, ECONNRESET); 7039 break; 7040 } 7041 break; 7042 case L2CAP_EV_RECV_RR: 7043 l2cap_pass_to_tx(chan, control); 7044 if (control->final) { 7045 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7046 7047 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) && 7048 !__chan_is_moving(chan)) { 7049 control->final = 0; 7050 l2cap_retransmit_all(chan, control); 7051 } 7052 7053 l2cap_ertm_send(chan); 7054 } else if (control->poll) { 7055 l2cap_send_i_or_rr_or_rnr(chan); 7056 } else { 7057 if (test_and_clear_bit(CONN_REMOTE_BUSY, 7058 &chan->conn_state) && 7059 chan->unacked_frames) 7060 __set_retrans_timer(chan); 7061 7062 l2cap_ertm_send(chan); 7063 } 7064 break; 7065 case L2CAP_EV_RECV_RNR: 7066 set_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7067 l2cap_pass_to_tx(chan, control); 7068 if (control && control->poll) { 7069 set_bit(CONN_SEND_FBIT, &chan->conn_state); 7070 l2cap_send_rr_or_rnr(chan, 0); 7071 } 7072 __clear_retrans_timer(chan); 7073 l2cap_seq_list_clear(&chan->retrans_list); 7074 break; 7075 case L2CAP_EV_RECV_REJ: 7076 l2cap_handle_rej(chan, control); 7077 break; 7078 case L2CAP_EV_RECV_SREJ: 7079 l2cap_handle_srej(chan, control); 7080 break; 7081 default: 7082 break; 7083 } 7084 7085 if (skb && !skb_in_use) { 7086 BT_DBG("Freeing %p", skb); 7087 kfree_skb(skb); 7088 } 7089 7090 return err; 7091} 7092 7093static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan, 7094 struct l2cap_ctrl *control, 7095 struct sk_buff *skb, u8 event) 7096{ 7097 int err = 0; 7098 u16 txseq = control->txseq; 7099 bool skb_in_use = false; 7100 7101 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb, 7102 event); 7103 7104 switch (event) { 7105 case L2CAP_EV_RECV_IFRAME: 7106 switch (l2cap_classify_txseq(chan, txseq)) { 7107 case L2CAP_TXSEQ_EXPECTED: 7108 /* Keep frame for reassembly later */ 7109 l2cap_pass_to_tx(chan, control); 7110 skb_queue_tail(&chan->srej_q, skb); 7111 skb_in_use = true; 7112 BT_DBG("Queued %p (queue len %d)", skb, 7113 skb_queue_len(&chan->srej_q)); 7114 7115 chan->expected_tx_seq = __next_seq(chan, txseq); 7116 break; 7117 case L2CAP_TXSEQ_EXPECTED_SREJ: 7118 l2cap_seq_list_pop(&chan->srej_list); 7119 7120 l2cap_pass_to_tx(chan, control); 7121 skb_queue_tail(&chan->srej_q, skb); 7122 skb_in_use = true; 7123 BT_DBG("Queued %p (queue len %d)", skb, 7124 skb_queue_len(&chan->srej_q)); 7125 7126 err = l2cap_rx_queued_iframes(chan); 7127 if (err) 7128 break; 7129 7130 break; 7131 case L2CAP_TXSEQ_UNEXPECTED: 7132 /* Got a frame that can't be reassembled yet. 7133 * Save it for later, and send SREJs to cover 7134 * the missing frames. 7135 */ 7136 skb_queue_tail(&chan->srej_q, skb); 7137 skb_in_use = true; 7138 BT_DBG("Queued %p (queue len %d)", skb, 7139 skb_queue_len(&chan->srej_q)); 7140 7141 l2cap_pass_to_tx(chan, control); 7142 l2cap_send_srej(chan, control->txseq); 7143 break; 7144 case L2CAP_TXSEQ_UNEXPECTED_SREJ: 7145 /* This frame was requested with an SREJ, but 7146 * some expected retransmitted frames are 7147 * missing. Request retransmission of missing 7148 * SREJ'd frames. 7149 */ 7150 skb_queue_tail(&chan->srej_q, skb); 7151 skb_in_use = true; 7152 BT_DBG("Queued %p (queue len %d)", skb, 7153 skb_queue_len(&chan->srej_q)); 7154 7155 l2cap_pass_to_tx(chan, control); 7156 l2cap_send_srej_list(chan, control->txseq); 7157 break; 7158 case L2CAP_TXSEQ_DUPLICATE_SREJ: 7159 /* We've already queued this frame. Drop this copy. */ 7160 l2cap_pass_to_tx(chan, control); 7161 break; 7162 case L2CAP_TXSEQ_DUPLICATE: 7163 /* Expecting a later sequence number, so this frame 7164 * was already received. Ignore it completely. 7165 */ 7166 break; 7167 case L2CAP_TXSEQ_INVALID_IGNORE: 7168 break; 7169 case L2CAP_TXSEQ_INVALID: 7170 default: 7171 l2cap_send_disconn_req(chan, ECONNRESET); 7172 break; 7173 } 7174 break; 7175 case L2CAP_EV_RECV_RR: 7176 l2cap_pass_to_tx(chan, control); 7177 if (control->final) { 7178 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7179 7180 if (!test_and_clear_bit(CONN_REJ_ACT, 7181 &chan->conn_state)) { 7182 control->final = 0; 7183 l2cap_retransmit_all(chan, control); 7184 } 7185 7186 l2cap_ertm_send(chan); 7187 } else if (control->poll) { 7188 if (test_and_clear_bit(CONN_REMOTE_BUSY, 7189 &chan->conn_state) && 7190 chan->unacked_frames) { 7191 __set_retrans_timer(chan); 7192 } 7193 7194 set_bit(CONN_SEND_FBIT, &chan->conn_state); 7195 l2cap_send_srej_tail(chan); 7196 } else { 7197 if (test_and_clear_bit(CONN_REMOTE_BUSY, 7198 &chan->conn_state) && 7199 chan->unacked_frames) 7200 __set_retrans_timer(chan); 7201 7202 l2cap_send_ack(chan); 7203 } 7204 break; 7205 case L2CAP_EV_RECV_RNR: 7206 set_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7207 l2cap_pass_to_tx(chan, control); 7208 if (control->poll) { 7209 l2cap_send_srej_tail(chan); 7210 } else { 7211 struct l2cap_ctrl rr_control; 7212 memset(&rr_control, 0, sizeof(rr_control)); 7213 rr_control.sframe = 1; 7214 rr_control.super = L2CAP_SUPER_RR; 7215 rr_control.reqseq = chan->buffer_seq; 7216 l2cap_send_sframe(chan, &rr_control); 7217 } 7218 7219 break; 7220 case L2CAP_EV_RECV_REJ: 7221 l2cap_handle_rej(chan, control); 7222 break; 7223 case L2CAP_EV_RECV_SREJ: 7224 l2cap_handle_srej(chan, control); 7225 break; 7226 } 7227 7228 if (skb && !skb_in_use) { 7229 BT_DBG("Freeing %p", skb); 7230 kfree_skb(skb); 7231 } 7232 7233 return err; 7234} 7235 7236static int l2cap_finish_move(struct l2cap_chan *chan) 7237{ 7238 BT_DBG("chan %p", chan); 7239 7240 chan->rx_state = L2CAP_RX_STATE_RECV; 7241 7242 if (chan->hs_hcon) 7243 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu; 7244 else 7245 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu; 7246 7247 return l2cap_resegment(chan); 7248} 7249 7250static int l2cap_rx_state_wait_p(struct l2cap_chan *chan, 7251 struct l2cap_ctrl *control, 7252 struct sk_buff *skb, u8 event) 7253{ 7254 int err; 7255 7256 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb, 7257 event); 7258 7259 if (!control->poll) 7260 return -EPROTO; 7261 7262 l2cap_process_reqseq(chan, control->reqseq); 7263 7264 if (!skb_queue_empty(&chan->tx_q)) 7265 chan->tx_send_head = skb_peek(&chan->tx_q); 7266 else 7267 chan->tx_send_head = NULL; 7268 7269 /* Rewind next_tx_seq to the point expected 7270 * by the receiver. 7271 */ 7272 chan->next_tx_seq = control->reqseq; 7273 chan->unacked_frames = 0; 7274 7275 err = l2cap_finish_move(chan); 7276 if (err) 7277 return err; 7278 7279 set_bit(CONN_SEND_FBIT, &chan->conn_state); 7280 l2cap_send_i_or_rr_or_rnr(chan); 7281 7282 if (event == L2CAP_EV_RECV_IFRAME) 7283 return -EPROTO; 7284 7285 return l2cap_rx_state_recv(chan, control, NULL, event); 7286} 7287 7288static int l2cap_rx_state_wait_f(struct l2cap_chan *chan, 7289 struct l2cap_ctrl *control, 7290 struct sk_buff *skb, u8 event) 7291{ 7292 int err; 7293 7294 if (!control->final) 7295 return -EPROTO; 7296 7297 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7298 7299 chan->rx_state = L2CAP_RX_STATE_RECV; 7300 l2cap_process_reqseq(chan, control->reqseq); 7301 7302 if (!skb_queue_empty(&chan->tx_q)) 7303 chan->tx_send_head = skb_peek(&chan->tx_q); 7304 else 7305 chan->tx_send_head = NULL; 7306 7307 /* Rewind next_tx_seq to the point expected 7308 * by the receiver. 7309 */ 7310 chan->next_tx_seq = control->reqseq; 7311 chan->unacked_frames = 0; 7312 7313 if (chan->hs_hcon) 7314 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu; 7315 else 7316 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu; 7317 7318 err = l2cap_resegment(chan); 7319 7320 if (!err) 7321 err = l2cap_rx_state_recv(chan, control, skb, event); 7322 7323 return err; 7324} 7325 7326static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq) 7327{ 7328 /* Make sure reqseq is for a packet that has been sent but not acked */ 7329 u16 unacked; 7330 7331 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq); 7332 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked; 7333} 7334 7335static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control, 7336 struct sk_buff *skb, u8 event) 7337{ 7338 int err = 0; 7339 7340 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan, 7341 control, skb, event, chan->rx_state); 7342 7343 if (__valid_reqseq(chan, control->reqseq)) { 7344 switch (chan->rx_state) { 7345 case L2CAP_RX_STATE_RECV: 7346 err = l2cap_rx_state_recv(chan, control, skb, event); 7347 break; 7348 case L2CAP_RX_STATE_SREJ_SENT: 7349 err = l2cap_rx_state_srej_sent(chan, control, skb, 7350 event); 7351 break; 7352 case L2CAP_RX_STATE_WAIT_P: 7353 err = l2cap_rx_state_wait_p(chan, control, skb, event); 7354 break; 7355 case L2CAP_RX_STATE_WAIT_F: 7356 err = l2cap_rx_state_wait_f(chan, control, skb, event); 7357 break; 7358 default: 7359 /* shut it down */ 7360 break; 7361 } 7362 } else { 7363 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d", 7364 control->reqseq, chan->next_tx_seq, 7365 chan->expected_ack_seq); 7366 l2cap_send_disconn_req(chan, ECONNRESET); 7367 } 7368 7369 return err; 7370} 7371 7372static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control, 7373 struct sk_buff *skb) 7374{ 7375 /* l2cap_reassemble_sdu may free skb, hence invalidate control, so store 7376 * the txseq field in advance to use it after l2cap_reassemble_sdu 7377 * returns and to avoid the race condition, for example: 7378 * 7379 * The current thread calls: 7380 * l2cap_reassemble_sdu 7381 * chan->ops->recv == l2cap_sock_recv_cb 7382 * __sock_queue_rcv_skb 7383 * Another thread calls: 7384 * bt_sock_recvmsg 7385 * skb_recv_datagram 7386 * skb_free_datagram 7387 * Then the current thread tries to access control, but it was freed by 7388 * skb_free_datagram. 7389 */ 7390 u16 txseq = control->txseq; 7391 7392 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb, 7393 chan->rx_state); 7394 7395 if (l2cap_classify_txseq(chan, txseq) == L2CAP_TXSEQ_EXPECTED) { 7396 l2cap_pass_to_tx(chan, control); 7397 7398 BT_DBG("buffer_seq %d->%d", chan->buffer_seq, 7399 __next_seq(chan, chan->buffer_seq)); 7400 7401 chan->buffer_seq = __next_seq(chan, chan->buffer_seq); 7402 7403 l2cap_reassemble_sdu(chan, skb, control); 7404 } else { 7405 if (chan->sdu) { 7406 kfree_skb(chan->sdu); 7407 chan->sdu = NULL; 7408 } 7409 chan->sdu_last_frag = NULL; 7410 chan->sdu_len = 0; 7411 7412 if (skb) { 7413 BT_DBG("Freeing %p", skb); 7414 kfree_skb(skb); 7415 } 7416 } 7417 7418 chan->last_acked_seq = txseq; 7419 chan->expected_tx_seq = __next_seq(chan, txseq); 7420 7421 return 0; 7422} 7423 7424static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) 7425{ 7426 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap; 7427 u16 len; 7428 u8 event; 7429 7430 __unpack_control(chan, skb); 7431 7432 len = skb->len; 7433 7434 /* 7435 * We can just drop the corrupted I-frame here. 7436 * Receiver will miss it and start proper recovery 7437 * procedures and ask for retransmission. 7438 */ 7439 if (l2cap_check_fcs(chan, skb)) 7440 goto drop; 7441 7442 if (!control->sframe && control->sar == L2CAP_SAR_START) 7443 len -= L2CAP_SDULEN_SIZE; 7444 7445 if (chan->fcs == L2CAP_FCS_CRC16) 7446 len -= L2CAP_FCS_SIZE; 7447 7448 if (len > chan->mps) { 7449 l2cap_send_disconn_req(chan, ECONNRESET); 7450 goto drop; 7451 } 7452 7453 if (chan->ops->filter) { 7454 if (chan->ops->filter(chan, skb)) 7455 goto drop; 7456 } 7457 7458 if (!control->sframe) { 7459 int err; 7460 7461 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d", 7462 control->sar, control->reqseq, control->final, 7463 control->txseq); 7464 7465 /* Validate F-bit - F=0 always valid, F=1 only 7466 * valid in TX WAIT_F 7467 */ 7468 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F) 7469 goto drop; 7470 7471 if (chan->mode != L2CAP_MODE_STREAMING) { 7472 event = L2CAP_EV_RECV_IFRAME; 7473 err = l2cap_rx(chan, control, skb, event); 7474 } else { 7475 err = l2cap_stream_rx(chan, control, skb); 7476 } 7477 7478 if (err) 7479 l2cap_send_disconn_req(chan, ECONNRESET); 7480 } else { 7481 const u8 rx_func_to_event[4] = { 7482 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ, 7483 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ 7484 }; 7485 7486 /* Only I-frames are expected in streaming mode */ 7487 if (chan->mode == L2CAP_MODE_STREAMING) 7488 goto drop; 7489 7490 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d", 7491 control->reqseq, control->final, control->poll, 7492 control->super); 7493 7494 if (len != 0) { 7495 BT_ERR("Trailing bytes: %d in sframe", len); 7496 l2cap_send_disconn_req(chan, ECONNRESET); 7497 goto drop; 7498 } 7499 7500 /* Validate F and P bits */ 7501 if (control->final && (control->poll || 7502 chan->tx_state != L2CAP_TX_STATE_WAIT_F)) 7503 goto drop; 7504 7505 event = rx_func_to_event[control->super]; 7506 if (l2cap_rx(chan, control, skb, event)) 7507 l2cap_send_disconn_req(chan, ECONNRESET); 7508 } 7509 7510 return 0; 7511 7512drop: 7513 kfree_skb(skb); 7514 return 0; 7515} 7516 7517static void l2cap_chan_le_send_credits(struct l2cap_chan *chan) 7518{ 7519 struct l2cap_conn *conn = chan->conn; 7520 struct l2cap_le_credits pkt; 7521 u16 return_credits; 7522 7523 return_credits = (chan->imtu / chan->mps) + 1; 7524 7525 if (chan->rx_credits >= return_credits) 7526 return; 7527 7528 return_credits -= chan->rx_credits; 7529 7530 BT_DBG("chan %p returning %u credits to sender", chan, return_credits); 7531 7532 chan->rx_credits += return_credits; 7533 7534 pkt.cid = cpu_to_le16(chan->scid); 7535 pkt.credits = cpu_to_le16(return_credits); 7536 7537 chan->ident = l2cap_get_ident(conn); 7538 7539 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt); 7540} 7541 7542static int l2cap_ecred_recv(struct l2cap_chan *chan, struct sk_buff *skb) 7543{ 7544 int err; 7545 7546 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len); 7547 7548 /* Wait recv to confirm reception before updating the credits */ 7549 err = chan->ops->recv(chan, skb); 7550 7551 /* Update credits whenever an SDU is received */ 7552 l2cap_chan_le_send_credits(chan); 7553 7554 return err; 7555} 7556 7557static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) 7558{ 7559 int err; 7560 7561 if (!chan->rx_credits) { 7562 BT_ERR("No credits to receive LE L2CAP data"); 7563 l2cap_send_disconn_req(chan, ECONNRESET); 7564 return -ENOBUFS; 7565 } 7566 7567 if (chan->imtu < skb->len) { 7568 BT_ERR("Too big LE L2CAP PDU"); 7569 return -ENOBUFS; 7570 } 7571 7572 chan->rx_credits--; 7573 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits); 7574 7575 /* Update if remote had run out of credits, this should only happens 7576 * if the remote is not using the entire MPS. 7577 */ 7578 if (!chan->rx_credits) 7579 l2cap_chan_le_send_credits(chan); 7580 7581 err = 0; 7582 7583 if (!chan->sdu) { 7584 u16 sdu_len; 7585 7586 sdu_len = get_unaligned_le16(skb->data); 7587 skb_pull(skb, L2CAP_SDULEN_SIZE); 7588 7589 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u", 7590 sdu_len, skb->len, chan->imtu); 7591 7592 if (sdu_len > chan->imtu) { 7593 BT_ERR("Too big LE L2CAP SDU length received"); 7594 err = -EMSGSIZE; 7595 goto failed; 7596 } 7597 7598 if (skb->len > sdu_len) { 7599 BT_ERR("Too much LE L2CAP data received"); 7600 err = -EINVAL; 7601 goto failed; 7602 } 7603 7604 if (skb->len == sdu_len) 7605 return l2cap_ecred_recv(chan, skb); 7606 7607 chan->sdu = skb; 7608 chan->sdu_len = sdu_len; 7609 chan->sdu_last_frag = skb; 7610 7611 /* Detect if remote is not able to use the selected MPS */ 7612 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) { 7613 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE; 7614 7615 /* Adjust the number of credits */ 7616 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len); 7617 chan->mps = mps_len; 7618 l2cap_chan_le_send_credits(chan); 7619 } 7620 7621 return 0; 7622 } 7623 7624 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u", 7625 chan->sdu->len, skb->len, chan->sdu_len); 7626 7627 if (chan->sdu->len + skb->len > chan->sdu_len) { 7628 BT_ERR("Too much LE L2CAP data received"); 7629 err = -EINVAL; 7630 goto failed; 7631 } 7632 7633 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag); 7634 skb = NULL; 7635 7636 if (chan->sdu->len == chan->sdu_len) { 7637 err = l2cap_ecred_recv(chan, chan->sdu); 7638 if (!err) { 7639 chan->sdu = NULL; 7640 chan->sdu_last_frag = NULL; 7641 chan->sdu_len = 0; 7642 } 7643 } 7644 7645failed: 7646 if (err) { 7647 kfree_skb(skb); 7648 kfree_skb(chan->sdu); 7649 chan->sdu = NULL; 7650 chan->sdu_last_frag = NULL; 7651 chan->sdu_len = 0; 7652 } 7653 7654 /* We can't return an error here since we took care of the skb 7655 * freeing internally. An error return would cause the caller to 7656 * do a double-free of the skb. 7657 */ 7658 return 0; 7659} 7660 7661static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid, 7662 struct sk_buff *skb) 7663{ 7664 struct l2cap_chan *chan; 7665 7666 chan = l2cap_get_chan_by_scid(conn, cid); 7667 if (!chan) { 7668 if (cid == L2CAP_CID_A2MP) { 7669 chan = a2mp_channel_create(conn, skb); 7670 if (!chan) { 7671 kfree_skb(skb); 7672 return; 7673 } 7674 7675 l2cap_chan_hold(chan); 7676 l2cap_chan_lock(chan); 7677 } else { 7678 BT_DBG("unknown cid 0x%4.4x", cid); 7679 /* Drop packet and return */ 7680 kfree_skb(skb); 7681 return; 7682 } 7683 } 7684 7685 BT_DBG("chan %p, len %d", chan, skb->len); 7686 7687 /* If we receive data on a fixed channel before the info req/rsp 7688 * procedure is done simply assume that the channel is supported 7689 * and mark it as ready. 7690 */ 7691 if (chan->chan_type == L2CAP_CHAN_FIXED) 7692 l2cap_chan_ready(chan); 7693 7694 if (chan->state != BT_CONNECTED) 7695 goto drop; 7696 7697 switch (chan->mode) { 7698 case L2CAP_MODE_LE_FLOWCTL: 7699 case L2CAP_MODE_EXT_FLOWCTL: 7700 if (l2cap_ecred_data_rcv(chan, skb) < 0) 7701 goto drop; 7702 7703 goto done; 7704 7705 case L2CAP_MODE_BASIC: 7706 /* If socket recv buffers overflows we drop data here 7707 * which is *bad* because L2CAP has to be reliable. 7708 * But we don't have any other choice. L2CAP doesn't 7709 * provide flow control mechanism. */ 7710 7711 if (chan->imtu < skb->len) { 7712 BT_ERR("Dropping L2CAP data: receive buffer overflow"); 7713 goto drop; 7714 } 7715 7716 if (!chan->ops->recv(chan, skb)) 7717 goto done; 7718 break; 7719 7720 case L2CAP_MODE_ERTM: 7721 case L2CAP_MODE_STREAMING: 7722 l2cap_data_rcv(chan, skb); 7723 goto done; 7724 7725 default: 7726 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode); 7727 break; 7728 } 7729 7730drop: 7731 kfree_skb(skb); 7732 7733done: 7734 l2cap_chan_unlock(chan); 7735 l2cap_chan_put(chan); 7736} 7737 7738static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm, 7739 struct sk_buff *skb) 7740{ 7741 struct hci_conn *hcon = conn->hcon; 7742 struct l2cap_chan *chan; 7743 7744 if (hcon->type != ACL_LINK) 7745 goto free_skb; 7746 7747 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst, 7748 ACL_LINK); 7749 if (!chan) 7750 goto free_skb; 7751 7752 BT_DBG("chan %p, len %d", chan, skb->len); 7753 7754 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED) 7755 goto drop; 7756 7757 if (chan->imtu < skb->len) 7758 goto drop; 7759 7760 /* Store remote BD_ADDR and PSM for msg_name */ 7761 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst); 7762 bt_cb(skb)->l2cap.psm = psm; 7763 7764 if (!chan->ops->recv(chan, skb)) { 7765 l2cap_chan_put(chan); 7766 return; 7767 } 7768 7769drop: 7770 l2cap_chan_put(chan); 7771free_skb: 7772 kfree_skb(skb); 7773} 7774 7775static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb) 7776{ 7777 struct l2cap_hdr *lh = (void *) skb->data; 7778 struct hci_conn *hcon = conn->hcon; 7779 u16 cid, len; 7780 __le16 psm; 7781 7782 if (hcon->state != BT_CONNECTED) { 7783 BT_DBG("queueing pending rx skb"); 7784 skb_queue_tail(&conn->pending_rx, skb); 7785 return; 7786 } 7787 7788 skb_pull(skb, L2CAP_HDR_SIZE); 7789 cid = __le16_to_cpu(lh->cid); 7790 len = __le16_to_cpu(lh->len); 7791 7792 if (len != skb->len) { 7793 kfree_skb(skb); 7794 return; 7795 } 7796 7797 /* Since we can't actively block incoming LE connections we must 7798 * at least ensure that we ignore incoming data from them. 7799 */ 7800 if (hcon->type == LE_LINK && 7801 hci_bdaddr_list_lookup(&hcon->hdev->reject_list, &hcon->dst, 7802 bdaddr_dst_type(hcon))) { 7803 kfree_skb(skb); 7804 return; 7805 } 7806 7807 BT_DBG("len %d, cid 0x%4.4x", len, cid); 7808 7809 switch (cid) { 7810 case L2CAP_CID_SIGNALING: 7811 l2cap_sig_channel(conn, skb); 7812 break; 7813 7814 case L2CAP_CID_CONN_LESS: 7815 psm = get_unaligned((__le16 *) skb->data); 7816 skb_pull(skb, L2CAP_PSMLEN_SIZE); 7817 l2cap_conless_channel(conn, psm, skb); 7818 break; 7819 7820 case L2CAP_CID_LE_SIGNALING: 7821 l2cap_le_sig_channel(conn, skb); 7822 break; 7823 7824 default: 7825 l2cap_data_channel(conn, cid, skb); 7826 break; 7827 } 7828} 7829 7830static void process_pending_rx(struct work_struct *work) 7831{ 7832 struct l2cap_conn *conn = container_of(work, struct l2cap_conn, 7833 pending_rx_work); 7834 struct sk_buff *skb; 7835 7836 BT_DBG(""); 7837 7838 while ((skb = skb_dequeue(&conn->pending_rx))) 7839 l2cap_recv_frame(conn, skb); 7840} 7841 7842static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon) 7843{ 7844 struct l2cap_conn *conn = hcon->l2cap_data; 7845 struct hci_chan *hchan; 7846 7847 if (conn) 7848 return conn; 7849 7850 hchan = hci_chan_create(hcon); 7851 if (!hchan) 7852 return NULL; 7853 7854 conn = kzalloc(sizeof(*conn), GFP_KERNEL); 7855 if (!conn) { 7856 hci_chan_del(hchan); 7857 return NULL; 7858 } 7859 7860 kref_init(&conn->ref); 7861 hcon->l2cap_data = conn; 7862 conn->hcon = hci_conn_get(hcon); 7863 conn->hchan = hchan; 7864 7865 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan); 7866 7867 switch (hcon->type) { 7868 case LE_LINK: 7869 if (hcon->hdev->le_mtu) { 7870 conn->mtu = hcon->hdev->le_mtu; 7871 break; 7872 } 7873 fallthrough; 7874 default: 7875 conn->mtu = hcon->hdev->acl_mtu; 7876 break; 7877 } 7878 7879 conn->feat_mask = 0; 7880 7881 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS; 7882 7883 if (hcon->type == ACL_LINK && 7884 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED)) 7885 conn->local_fixed_chan |= L2CAP_FC_A2MP; 7886 7887 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) && 7888 (bredr_sc_enabled(hcon->hdev) || 7889 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP))) 7890 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR; 7891 7892 mutex_init(&conn->ident_lock); 7893 mutex_init(&conn->chan_lock); 7894 7895 INIT_LIST_HEAD(&conn->chan_l); 7896 INIT_LIST_HEAD(&conn->users); 7897 7898 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout); 7899 7900 skb_queue_head_init(&conn->pending_rx); 7901 INIT_WORK(&conn->pending_rx_work, process_pending_rx); 7902 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr); 7903 7904 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM; 7905 7906 return conn; 7907} 7908 7909static bool is_valid_psm(u16 psm, u8 dst_type) { 7910 if (!psm) 7911 return false; 7912 7913 if (bdaddr_type_is_le(dst_type)) 7914 return (psm <= 0x00ff); 7915 7916 /* PSM must be odd and lsb of upper byte must be 0 */ 7917 return ((psm & 0x0101) == 0x0001); 7918} 7919 7920struct l2cap_chan_data { 7921 struct l2cap_chan *chan; 7922 struct pid *pid; 7923 int count; 7924}; 7925 7926static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data) 7927{ 7928 struct l2cap_chan_data *d = data; 7929 struct pid *pid; 7930 7931 if (chan == d->chan) 7932 return; 7933 7934 if (!test_bit(FLAG_DEFER_SETUP, &chan->flags)) 7935 return; 7936 7937 pid = chan->ops->get_peer_pid(chan); 7938 7939 /* Only count deferred channels with the same PID/PSM */ 7940 if (d->pid != pid || chan->psm != d->chan->psm || chan->ident || 7941 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT) 7942 return; 7943 7944 d->count++; 7945} 7946 7947int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, 7948 bdaddr_t *dst, u8 dst_type) 7949{ 7950 struct l2cap_conn *conn; 7951 struct hci_conn *hcon; 7952 struct hci_dev *hdev; 7953 int err; 7954 7955 BT_DBG("%pMR -> %pMR (type %u) psm 0x%4.4x mode 0x%2.2x", &chan->src, 7956 dst, dst_type, __le16_to_cpu(psm), chan->mode); 7957 7958 hdev = hci_get_route(dst, &chan->src, chan->src_type); 7959 if (!hdev) 7960 return -EHOSTUNREACH; 7961 7962 hci_dev_lock(hdev); 7963 7964 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid && 7965 chan->chan_type != L2CAP_CHAN_RAW) { 7966 err = -EINVAL; 7967 goto done; 7968 } 7969 7970 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) { 7971 err = -EINVAL; 7972 goto done; 7973 } 7974 7975 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) { 7976 err = -EINVAL; 7977 goto done; 7978 } 7979 7980 switch (chan->mode) { 7981 case L2CAP_MODE_BASIC: 7982 break; 7983 case L2CAP_MODE_LE_FLOWCTL: 7984 break; 7985 case L2CAP_MODE_EXT_FLOWCTL: 7986 if (!enable_ecred) { 7987 err = -EOPNOTSUPP; 7988 goto done; 7989 } 7990 break; 7991 case L2CAP_MODE_ERTM: 7992 case L2CAP_MODE_STREAMING: 7993 if (!disable_ertm) 7994 break; 7995 fallthrough; 7996 default: 7997 err = -EOPNOTSUPP; 7998 goto done; 7999 } 8000 8001 switch (chan->state) { 8002 case BT_CONNECT: 8003 case BT_CONNECT2: 8004 case BT_CONFIG: 8005 /* Already connecting */ 8006 err = 0; 8007 goto done; 8008 8009 case BT_CONNECTED: 8010 /* Already connected */ 8011 err = -EISCONN; 8012 goto done; 8013 8014 case BT_OPEN: 8015 case BT_BOUND: 8016 /* Can connect */ 8017 break; 8018 8019 default: 8020 err = -EBADFD; 8021 goto done; 8022 } 8023 8024 /* Set destination address and psm */ 8025 bacpy(&chan->dst, dst); 8026 chan->dst_type = dst_type; 8027 8028 chan->psm = psm; 8029 chan->dcid = cid; 8030 8031 if (bdaddr_type_is_le(dst_type)) { 8032 /* Convert from L2CAP channel address type to HCI address type 8033 */ 8034 if (dst_type == BDADDR_LE_PUBLIC) 8035 dst_type = ADDR_LE_DEV_PUBLIC; 8036 else 8037 dst_type = ADDR_LE_DEV_RANDOM; 8038 8039 if (hci_dev_test_flag(hdev, HCI_ADVERTISING)) 8040 hcon = hci_connect_le(hdev, dst, dst_type, 8041 chan->sec_level, 8042 HCI_LE_CONN_TIMEOUT, 8043 HCI_ROLE_SLAVE, NULL); 8044 else 8045 hcon = hci_connect_le_scan(hdev, dst, dst_type, 8046 chan->sec_level, 8047 HCI_LE_CONN_TIMEOUT, 8048 CONN_REASON_L2CAP_CHAN); 8049 8050 } else { 8051 u8 auth_type = l2cap_get_auth_type(chan); 8052 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type, 8053 CONN_REASON_L2CAP_CHAN); 8054 } 8055 8056 if (IS_ERR(hcon)) { 8057 err = PTR_ERR(hcon); 8058 goto done; 8059 } 8060 8061 conn = l2cap_conn_add(hcon); 8062 if (!conn) { 8063 hci_conn_drop(hcon); 8064 err = -ENOMEM; 8065 goto done; 8066 } 8067 8068 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) { 8069 struct l2cap_chan_data data; 8070 8071 data.chan = chan; 8072 data.pid = chan->ops->get_peer_pid(chan); 8073 data.count = 1; 8074 8075 l2cap_chan_list(conn, l2cap_chan_by_pid, &data); 8076 8077 /* Check if there isn't too many channels being connected */ 8078 if (data.count > L2CAP_ECRED_CONN_SCID_MAX) { 8079 hci_conn_drop(hcon); 8080 err = -EPROTO; 8081 goto done; 8082 } 8083 } 8084 8085 mutex_lock(&conn->chan_lock); 8086 l2cap_chan_lock(chan); 8087 8088 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) { 8089 hci_conn_drop(hcon); 8090 err = -EBUSY; 8091 goto chan_unlock; 8092 } 8093 8094 /* Update source addr of the socket */ 8095 bacpy(&chan->src, &hcon->src); 8096 chan->src_type = bdaddr_src_type(hcon); 8097 8098 __l2cap_chan_add(conn, chan); 8099 8100 /* l2cap_chan_add takes its own ref so we can drop this one */ 8101 hci_conn_drop(hcon); 8102 8103 l2cap_state_change(chan, BT_CONNECT); 8104 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 8105 8106 /* Release chan->sport so that it can be reused by other 8107 * sockets (as it's only used for listening sockets). 8108 */ 8109 write_lock(&chan_list_lock); 8110 chan->sport = 0; 8111 write_unlock(&chan_list_lock); 8112 8113 if (hcon->state == BT_CONNECTED) { 8114 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 8115 __clear_chan_timer(chan); 8116 if (l2cap_chan_check_security(chan, true)) 8117 l2cap_state_change(chan, BT_CONNECTED); 8118 } else 8119 l2cap_do_start(chan); 8120 } 8121 8122 err = 0; 8123 8124chan_unlock: 8125 l2cap_chan_unlock(chan); 8126 mutex_unlock(&conn->chan_lock); 8127done: 8128 hci_dev_unlock(hdev); 8129 hci_dev_put(hdev); 8130 return err; 8131} 8132EXPORT_SYMBOL_GPL(l2cap_chan_connect); 8133 8134static void l2cap_ecred_reconfigure(struct l2cap_chan *chan) 8135{ 8136 struct l2cap_conn *conn = chan->conn; 8137 struct { 8138 struct l2cap_ecred_reconf_req req; 8139 __le16 scid; 8140 } pdu; 8141 8142 pdu.req.mtu = cpu_to_le16(chan->imtu); 8143 pdu.req.mps = cpu_to_le16(chan->mps); 8144 pdu.scid = cpu_to_le16(chan->scid); 8145 8146 chan->ident = l2cap_get_ident(conn); 8147 8148 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_RECONF_REQ, 8149 sizeof(pdu), &pdu); 8150} 8151 8152int l2cap_chan_reconfigure(struct l2cap_chan *chan, __u16 mtu) 8153{ 8154 if (chan->imtu > mtu) 8155 return -EINVAL; 8156 8157 BT_DBG("chan %p mtu 0x%4.4x", chan, mtu); 8158 8159 chan->imtu = mtu; 8160 8161 l2cap_ecred_reconfigure(chan); 8162 8163 return 0; 8164} 8165 8166/* ---- L2CAP interface with lower layer (HCI) ---- */ 8167 8168int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr) 8169{ 8170 int exact = 0, lm1 = 0, lm2 = 0; 8171 struct l2cap_chan *c; 8172 8173 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr); 8174 8175 /* Find listening sockets and check their link_mode */ 8176 read_lock(&chan_list_lock); 8177 list_for_each_entry(c, &chan_list, global_l) { 8178 if (c->state != BT_LISTEN) 8179 continue; 8180 8181 if (!bacmp(&c->src, &hdev->bdaddr)) { 8182 lm1 |= HCI_LM_ACCEPT; 8183 if (test_bit(FLAG_ROLE_SWITCH, &c->flags)) 8184 lm1 |= HCI_LM_MASTER; 8185 exact++; 8186 } else if (!bacmp(&c->src, BDADDR_ANY)) { 8187 lm2 |= HCI_LM_ACCEPT; 8188 if (test_bit(FLAG_ROLE_SWITCH, &c->flags)) 8189 lm2 |= HCI_LM_MASTER; 8190 } 8191 } 8192 read_unlock(&chan_list_lock); 8193 8194 return exact ? lm1 : lm2; 8195} 8196 8197/* Find the next fixed channel in BT_LISTEN state, continue iteration 8198 * from an existing channel in the list or from the beginning of the 8199 * global list (by passing NULL as first parameter). 8200 */ 8201static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c, 8202 struct hci_conn *hcon) 8203{ 8204 u8 src_type = bdaddr_src_type(hcon); 8205 8206 read_lock(&chan_list_lock); 8207 8208 if (c) 8209 c = list_next_entry(c, global_l); 8210 else 8211 c = list_entry(chan_list.next, typeof(*c), global_l); 8212 8213 list_for_each_entry_from(c, &chan_list, global_l) { 8214 if (c->chan_type != L2CAP_CHAN_FIXED) 8215 continue; 8216 if (c->state != BT_LISTEN) 8217 continue; 8218 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY)) 8219 continue; 8220 if (src_type != c->src_type) 8221 continue; 8222 8223 c = l2cap_chan_hold_unless_zero(c); 8224 read_unlock(&chan_list_lock); 8225 return c; 8226 } 8227 8228 read_unlock(&chan_list_lock); 8229 8230 return NULL; 8231} 8232 8233static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status) 8234{ 8235 struct hci_dev *hdev = hcon->hdev; 8236 struct l2cap_conn *conn; 8237 struct l2cap_chan *pchan; 8238 u8 dst_type; 8239 8240 if (hcon->type != ACL_LINK && hcon->type != LE_LINK) 8241 return; 8242 8243 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status); 8244 8245 if (status) { 8246 l2cap_conn_del(hcon, bt_to_errno(status)); 8247 return; 8248 } 8249 8250 conn = l2cap_conn_add(hcon); 8251 if (!conn) 8252 return; 8253 8254 dst_type = bdaddr_dst_type(hcon); 8255 8256 /* If device is blocked, do not create channels for it */ 8257 if (hci_bdaddr_list_lookup(&hdev->reject_list, &hcon->dst, dst_type)) 8258 return; 8259 8260 /* Find fixed channels and notify them of the new connection. We 8261 * use multiple individual lookups, continuing each time where 8262 * we left off, because the list lock would prevent calling the 8263 * potentially sleeping l2cap_chan_lock() function. 8264 */ 8265 pchan = l2cap_global_fixed_chan(NULL, hcon); 8266 while (pchan) { 8267 struct l2cap_chan *chan, *next; 8268 8269 /* Client fixed channels should override server ones */ 8270 if (__l2cap_get_chan_by_dcid(conn, pchan->scid)) 8271 goto next; 8272 8273 l2cap_chan_lock(pchan); 8274 chan = pchan->ops->new_connection(pchan); 8275 if (chan) { 8276 bacpy(&chan->src, &hcon->src); 8277 bacpy(&chan->dst, &hcon->dst); 8278 chan->src_type = bdaddr_src_type(hcon); 8279 chan->dst_type = dst_type; 8280 8281 __l2cap_chan_add(conn, chan); 8282 } 8283 8284 l2cap_chan_unlock(pchan); 8285next: 8286 next = l2cap_global_fixed_chan(pchan, hcon); 8287 l2cap_chan_put(pchan); 8288 pchan = next; 8289 } 8290 8291 l2cap_conn_ready(conn); 8292} 8293 8294int l2cap_disconn_ind(struct hci_conn *hcon) 8295{ 8296 struct l2cap_conn *conn = hcon->l2cap_data; 8297 8298 BT_DBG("hcon %p", hcon); 8299 8300 if (!conn) 8301 return HCI_ERROR_REMOTE_USER_TERM; 8302 return conn->disc_reason; 8303} 8304 8305static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason) 8306{ 8307 if (hcon->type != ACL_LINK && hcon->type != LE_LINK) 8308 return; 8309 8310 BT_DBG("hcon %p reason %d", hcon, reason); 8311 8312 l2cap_conn_del(hcon, bt_to_errno(reason)); 8313} 8314 8315static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt) 8316{ 8317 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) 8318 return; 8319 8320 if (encrypt == 0x00) { 8321 if (chan->sec_level == BT_SECURITY_MEDIUM) { 8322 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT); 8323 } else if (chan->sec_level == BT_SECURITY_HIGH || 8324 chan->sec_level == BT_SECURITY_FIPS) 8325 l2cap_chan_close(chan, ECONNREFUSED); 8326 } else { 8327 if (chan->sec_level == BT_SECURITY_MEDIUM) 8328 __clear_chan_timer(chan); 8329 } 8330} 8331 8332static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) 8333{ 8334 struct l2cap_conn *conn = hcon->l2cap_data; 8335 struct l2cap_chan *chan; 8336 8337 if (!conn) 8338 return; 8339 8340 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt); 8341 8342 mutex_lock(&conn->chan_lock); 8343 8344 list_for_each_entry(chan, &conn->chan_l, list) { 8345 l2cap_chan_lock(chan); 8346 8347 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid, 8348 state_to_string(chan->state)); 8349 8350 if (chan->scid == L2CAP_CID_A2MP) { 8351 l2cap_chan_unlock(chan); 8352 continue; 8353 } 8354 8355 if (!status && encrypt) 8356 chan->sec_level = hcon->sec_level; 8357 8358 if (!__l2cap_no_conn_pending(chan)) { 8359 l2cap_chan_unlock(chan); 8360 continue; 8361 } 8362 8363 if (!status && (chan->state == BT_CONNECTED || 8364 chan->state == BT_CONFIG)) { 8365 chan->ops->resume(chan); 8366 l2cap_check_encryption(chan, encrypt); 8367 l2cap_chan_unlock(chan); 8368 continue; 8369 } 8370 8371 if (chan->state == BT_CONNECT) { 8372 if (!status && l2cap_check_enc_key_size(hcon)) 8373 l2cap_start_connection(chan); 8374 else 8375 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); 8376 } else if (chan->state == BT_CONNECT2 && 8377 !(chan->mode == L2CAP_MODE_EXT_FLOWCTL || 8378 chan->mode == L2CAP_MODE_LE_FLOWCTL)) { 8379 struct l2cap_conn_rsp rsp; 8380 __u16 res, stat; 8381 8382 if (!status && l2cap_check_enc_key_size(hcon)) { 8383 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 8384 res = L2CAP_CR_PEND; 8385 stat = L2CAP_CS_AUTHOR_PEND; 8386 chan->ops->defer(chan); 8387 } else { 8388 l2cap_state_change(chan, BT_CONFIG); 8389 res = L2CAP_CR_SUCCESS; 8390 stat = L2CAP_CS_NO_INFO; 8391 } 8392 } else { 8393 l2cap_state_change(chan, BT_DISCONN); 8394 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); 8395 res = L2CAP_CR_SEC_BLOCK; 8396 stat = L2CAP_CS_NO_INFO; 8397 } 8398 8399 rsp.scid = cpu_to_le16(chan->dcid); 8400 rsp.dcid = cpu_to_le16(chan->scid); 8401 rsp.result = cpu_to_le16(res); 8402 rsp.status = cpu_to_le16(stat); 8403 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, 8404 sizeof(rsp), &rsp); 8405 8406 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) && 8407 res == L2CAP_CR_SUCCESS) { 8408 char buf[128]; 8409 set_bit(CONF_REQ_SENT, &chan->conf_state); 8410 l2cap_send_cmd(conn, l2cap_get_ident(conn), 8411 L2CAP_CONF_REQ, 8412 l2cap_build_conf_req(chan, buf, sizeof(buf)), 8413 buf); 8414 chan->num_conf_req++; 8415 } 8416 } 8417 8418 l2cap_chan_unlock(chan); 8419 } 8420 8421 mutex_unlock(&conn->chan_lock); 8422} 8423 8424void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags) 8425{ 8426 struct l2cap_conn *conn = hcon->l2cap_data; 8427 struct l2cap_hdr *hdr; 8428 int len; 8429 8430 /* For AMP controller do not create l2cap conn */ 8431 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY) 8432 goto drop; 8433 8434 if (!conn) 8435 conn = l2cap_conn_add(hcon); 8436 8437 if (!conn) 8438 goto drop; 8439 8440 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags); 8441 8442 switch (flags) { 8443 case ACL_START: 8444 case ACL_START_NO_FLUSH: 8445 case ACL_COMPLETE: 8446 if (conn->rx_len) { 8447 BT_ERR("Unexpected start frame (len %d)", skb->len); 8448 kfree_skb(conn->rx_skb); 8449 conn->rx_skb = NULL; 8450 conn->rx_len = 0; 8451 l2cap_conn_unreliable(conn, ECOMM); 8452 } 8453 8454 /* Start fragment always begin with Basic L2CAP header */ 8455 if (skb->len < L2CAP_HDR_SIZE) { 8456 BT_ERR("Frame is too short (len %d)", skb->len); 8457 l2cap_conn_unreliable(conn, ECOMM); 8458 goto drop; 8459 } 8460 8461 hdr = (struct l2cap_hdr *) skb->data; 8462 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE; 8463 8464 if (len == skb->len) { 8465 /* Complete frame received */ 8466 l2cap_recv_frame(conn, skb); 8467 return; 8468 } 8469 8470 BT_DBG("Start: total len %d, frag len %d", len, skb->len); 8471 8472 if (skb->len > len) { 8473 BT_ERR("Frame is too long (len %d, expected len %d)", 8474 skb->len, len); 8475 l2cap_conn_unreliable(conn, ECOMM); 8476 goto drop; 8477 } 8478 8479 /* Allocate skb for the complete frame (with header) */ 8480 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL); 8481 if (!conn->rx_skb) 8482 goto drop; 8483 8484 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len), 8485 skb->len); 8486 conn->rx_len = len - skb->len; 8487 break; 8488 8489 case ACL_CONT: 8490 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len); 8491 8492 if (!conn->rx_len) { 8493 BT_ERR("Unexpected continuation frame (len %d)", skb->len); 8494 l2cap_conn_unreliable(conn, ECOMM); 8495 goto drop; 8496 } 8497 8498 if (skb->len > conn->rx_len) { 8499 BT_ERR("Fragment is too long (len %d, expected %d)", 8500 skb->len, conn->rx_len); 8501 kfree_skb(conn->rx_skb); 8502 conn->rx_skb = NULL; 8503 conn->rx_len = 0; 8504 l2cap_conn_unreliable(conn, ECOMM); 8505 goto drop; 8506 } 8507 8508 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len), 8509 skb->len); 8510 conn->rx_len -= skb->len; 8511 8512 if (!conn->rx_len) { 8513 /* Complete frame received. l2cap_recv_frame 8514 * takes ownership of the skb so set the global 8515 * rx_skb pointer to NULL first. 8516 */ 8517 struct sk_buff *rx_skb = conn->rx_skb; 8518 conn->rx_skb = NULL; 8519 l2cap_recv_frame(conn, rx_skb); 8520 } 8521 break; 8522 } 8523 8524drop: 8525 kfree_skb(skb); 8526} 8527 8528static struct hci_cb l2cap_cb = { 8529 .name = "L2CAP", 8530 .connect_cfm = l2cap_connect_cfm, 8531 .disconn_cfm = l2cap_disconn_cfm, 8532 .security_cfm = l2cap_security_cfm, 8533}; 8534 8535static int l2cap_debugfs_show(struct seq_file *f, void *p) 8536{ 8537 struct l2cap_chan *c; 8538 8539 read_lock(&chan_list_lock); 8540 8541 list_for_each_entry(c, &chan_list, global_l) { 8542 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n", 8543 &c->src, c->src_type, &c->dst, c->dst_type, 8544 c->state, __le16_to_cpu(c->psm), 8545 c->scid, c->dcid, c->imtu, c->omtu, 8546 c->sec_level, c->mode); 8547 } 8548 8549 read_unlock(&chan_list_lock); 8550 8551 return 0; 8552} 8553 8554DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs); 8555 8556static struct dentry *l2cap_debugfs; 8557 8558int __init l2cap_init(void) 8559{ 8560 int err; 8561 8562 err = l2cap_init_sockets(); 8563 if (err < 0) 8564 return err; 8565 8566 hci_register_cb(&l2cap_cb); 8567 8568 if (IS_ERR_OR_NULL(bt_debugfs)) 8569 return 0; 8570 8571 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs, 8572 NULL, &l2cap_debugfs_fops); 8573 8574 return 0; 8575} 8576 8577void l2cap_exit(void) 8578{ 8579 debugfs_remove(l2cap_debugfs); 8580 hci_unregister_cb(&l2cap_cb); 8581 l2cap_cleanup_sockets(); 8582} 8583 8584module_param(disable_ertm, bool, 0644); 8585MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode"); 8586 8587module_param(enable_ecred, bool, 0644); 8588MODULE_PARM_DESC(enable_ecred, "Enable enhanced credit flow control mode"); 8589