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 47 bool disable_ertm; 48 bool enable_ecred = IS_ENABLED(CONFIG_BT_LE_L2CAP_ECRED); 49 50 static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD; 51 52 static LIST_HEAD(chan_list); 53 static DEFINE_RWLOCK(chan_list_lock); 54 55 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, 56 u8 code, u8 ident, u16 dlen, void *data); 57 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, 58 void *data); 59 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size); 60 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err); 61 62 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control, 63 struct sk_buff_head *skbs, u8 event); 64 static void l2cap_retrans_timeout(struct work_struct *work); 65 static void l2cap_monitor_timeout(struct work_struct *work); 66 static void l2cap_ack_timeout(struct work_struct *work); 67 68 static 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 80 static inline u8 bdaddr_src_type(struct hci_conn *hcon) 81 { 82 return bdaddr_type(hcon->type, hcon->src_type); 83 } 84 85 static 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 92 static 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 } 103 104 static 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 */ 119 static 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 */ 140 static 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 } 157 158 static 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 } 169 170 static 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 } 187 188 static 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 } 205 206 int 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 } 244 245 done: 246 write_unlock(&chan_list_lock); 247 return err; 248 } 249 EXPORT_SYMBOL_GPL(l2cap_add_psm); 250 251 int 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 } 265 266 static 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 } 282 283 static 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 } 291 292 static 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 } 298 299 static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err) 300 { 301 chan->ops->state_change(chan, chan->state, err); 302 } 303 304 static 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 } 312 313 static 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 } 321 322 static 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 */ 345 346 static 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 } 368 369 static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list) 370 { 371 kfree(seq_list->list); 372 } 373 374 static 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 } 380 381 static 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 } 396 397 static 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 } 410 411 static 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 } 428 429 static 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 mutex_lock(&conn->chan_lock); 439 /* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling 440 * this work. No need to call l2cap_chan_hold(chan) here again. 441 */ 442 l2cap_chan_lock(chan); 443 444 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG) 445 reason = ECONNREFUSED; 446 else if (chan->state == BT_CONNECT && 447 chan->sec_level != BT_SECURITY_SDP) 448 reason = ECONNREFUSED; 449 else 450 reason = ETIMEDOUT; 451 452 l2cap_chan_close(chan, reason); 453 454 chan->ops->close(chan); 455 456 l2cap_chan_unlock(chan); 457 l2cap_chan_put(chan); 458 459 mutex_unlock(&conn->chan_lock); 460 } 461 462 struct l2cap_chan *l2cap_chan_create(void) 463 { 464 struct l2cap_chan *chan; 465 466 chan = kzalloc(sizeof(*chan), GFP_ATOMIC); 467 if (!chan) 468 return NULL; 469 470 skb_queue_head_init(&chan->tx_q); 471 skb_queue_head_init(&chan->srej_q); 472 mutex_init(&chan->lock); 473 474 /* Set default lock nesting level */ 475 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL); 476 477 write_lock(&chan_list_lock); 478 list_add(&chan->global_l, &chan_list); 479 write_unlock(&chan_list_lock); 480 481 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout); 482 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout); 483 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout); 484 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout); 485 486 chan->state = BT_OPEN; 487 488 kref_init(&chan->kref); 489 490 /* This flag is cleared in l2cap_chan_ready() */ 491 set_bit(CONF_NOT_COMPLETE, &chan->conf_state); 492 493 BT_DBG("chan %p", chan); 494 495 return chan; 496 } 497 EXPORT_SYMBOL_GPL(l2cap_chan_create); 498 499 static void l2cap_chan_destroy(struct kref *kref) 500 { 501 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref); 502 503 BT_DBG("chan %p", chan); 504 505 write_lock(&chan_list_lock); 506 list_del(&chan->global_l); 507 write_unlock(&chan_list_lock); 508 509 kfree(chan); 510 } 511 512 void l2cap_chan_hold(struct l2cap_chan *c) 513 { 514 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref)); 515 516 kref_get(&c->kref); 517 } 518 519 struct l2cap_chan *l2cap_chan_hold_unless_zero(struct l2cap_chan *c) 520 { 521 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref)); 522 523 if (!kref_get_unless_zero(&c->kref)) 524 return NULL; 525 526 return c; 527 } 528 529 void l2cap_chan_put(struct l2cap_chan *c) 530 { 531 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref)); 532 533 kref_put(&c->kref, l2cap_chan_destroy); 534 } 535 EXPORT_SYMBOL_GPL(l2cap_chan_put); 536 537 void l2cap_chan_set_defaults(struct l2cap_chan *chan) 538 { 539 chan->fcs = L2CAP_FCS_CRC16; 540 chan->max_tx = L2CAP_DEFAULT_MAX_TX; 541 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW; 542 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW; 543 chan->remote_max_tx = chan->max_tx; 544 chan->remote_tx_win = chan->tx_win; 545 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW; 546 chan->sec_level = BT_SECURITY_LOW; 547 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO; 548 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO; 549 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO; 550 551 chan->conf_state = 0; 552 set_bit(CONF_NOT_COMPLETE, &chan->conf_state); 553 554 set_bit(FLAG_FORCE_ACTIVE, &chan->flags); 555 } 556 EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults); 557 558 static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits) 559 { 560 chan->sdu = NULL; 561 chan->sdu_last_frag = NULL; 562 chan->sdu_len = 0; 563 chan->tx_credits = tx_credits; 564 /* Derive MPS from connection MTU to stop HCI fragmentation */ 565 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE); 566 /* Give enough credits for a full packet */ 567 chan->rx_credits = (chan->imtu / chan->mps) + 1; 568 569 skb_queue_head_init(&chan->tx_q); 570 } 571 572 static void l2cap_ecred_init(struct l2cap_chan *chan, u16 tx_credits) 573 { 574 l2cap_le_flowctl_init(chan, tx_credits); 575 576 /* L2CAP implementations shall support a minimum MPS of 64 octets */ 577 if (chan->mps < L2CAP_ECRED_MIN_MPS) { 578 chan->mps = L2CAP_ECRED_MIN_MPS; 579 chan->rx_credits = (chan->imtu / chan->mps) + 1; 580 } 581 } 582 583 void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan) 584 { 585 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn, 586 __le16_to_cpu(chan->psm), chan->dcid); 587 588 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM; 589 590 chan->conn = conn; 591 592 switch (chan->chan_type) { 593 case L2CAP_CHAN_CONN_ORIENTED: 594 /* Alloc CID for connection-oriented socket */ 595 chan->scid = l2cap_alloc_cid(conn); 596 if (conn->hcon->type == ACL_LINK) 597 chan->omtu = L2CAP_DEFAULT_MTU; 598 break; 599 600 case L2CAP_CHAN_CONN_LESS: 601 /* Connectionless socket */ 602 chan->scid = L2CAP_CID_CONN_LESS; 603 chan->dcid = L2CAP_CID_CONN_LESS; 604 chan->omtu = L2CAP_DEFAULT_MTU; 605 break; 606 607 case L2CAP_CHAN_FIXED: 608 /* Caller will set CID and CID specific MTU values */ 609 break; 610 611 default: 612 /* Raw socket can send/recv signalling messages only */ 613 chan->scid = L2CAP_CID_SIGNALING; 614 chan->dcid = L2CAP_CID_SIGNALING; 615 chan->omtu = L2CAP_DEFAULT_MTU; 616 } 617 618 chan->local_id = L2CAP_BESTEFFORT_ID; 619 chan->local_stype = L2CAP_SERV_BESTEFFORT; 620 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE; 621 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME; 622 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT; 623 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO; 624 625 l2cap_chan_hold(chan); 626 627 /* Only keep a reference for fixed channels if they requested it */ 628 if (chan->chan_type != L2CAP_CHAN_FIXED || 629 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags)) 630 hci_conn_hold(conn->hcon); 631 632 list_add(&chan->list, &conn->chan_l); 633 } 634 635 void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan) 636 { 637 mutex_lock(&conn->chan_lock); 638 __l2cap_chan_add(conn, chan); 639 mutex_unlock(&conn->chan_lock); 640 } 641 642 void l2cap_chan_del(struct l2cap_chan *chan, int err) 643 { 644 struct l2cap_conn *conn = chan->conn; 645 646 __clear_chan_timer(chan); 647 648 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err, 649 state_to_string(chan->state)); 650 651 chan->ops->teardown(chan, err); 652 653 if (conn) { 654 struct amp_mgr *mgr = conn->hcon->amp_mgr; 655 /* Delete from channel list */ 656 list_del(&chan->list); 657 658 l2cap_chan_put(chan); 659 660 chan->conn = NULL; 661 662 /* Reference was only held for non-fixed channels or 663 * fixed channels that explicitly requested it using the 664 * FLAG_HOLD_HCI_CONN flag. 665 */ 666 if (chan->chan_type != L2CAP_CHAN_FIXED || 667 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags)) 668 hci_conn_drop(conn->hcon); 669 670 if (mgr && mgr->bredr_chan == chan) 671 mgr->bredr_chan = NULL; 672 } 673 674 if (chan->hs_hchan) { 675 struct hci_chan *hs_hchan = chan->hs_hchan; 676 677 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan); 678 amp_disconnect_logical_link(hs_hchan); 679 } 680 681 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state)) 682 return; 683 684 switch (chan->mode) { 685 case L2CAP_MODE_BASIC: 686 break; 687 688 case L2CAP_MODE_LE_FLOWCTL: 689 case L2CAP_MODE_EXT_FLOWCTL: 690 skb_queue_purge(&chan->tx_q); 691 break; 692 693 case L2CAP_MODE_ERTM: 694 __clear_retrans_timer(chan); 695 __clear_monitor_timer(chan); 696 __clear_ack_timer(chan); 697 698 skb_queue_purge(&chan->srej_q); 699 700 l2cap_seq_list_free(&chan->srej_list); 701 l2cap_seq_list_free(&chan->retrans_list); 702 fallthrough; 703 704 case L2CAP_MODE_STREAMING: 705 skb_queue_purge(&chan->tx_q); 706 break; 707 } 708 } 709 EXPORT_SYMBOL_GPL(l2cap_chan_del); 710 711 static void __l2cap_chan_list_id(struct l2cap_conn *conn, u16 id, 712 l2cap_chan_func_t func, void *data) 713 { 714 struct l2cap_chan *chan, *l; 715 716 list_for_each_entry_safe(chan, l, &conn->chan_l, list) { 717 if (chan->ident == id) 718 func(chan, data); 719 } 720 } 721 722 static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, 723 void *data) 724 { 725 struct l2cap_chan *chan; 726 727 list_for_each_entry(chan, &conn->chan_l, list) { 728 func(chan, data); 729 } 730 } 731 732 void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, 733 void *data) 734 { 735 if (!conn) 736 return; 737 738 mutex_lock(&conn->chan_lock); 739 __l2cap_chan_list(conn, func, data); 740 mutex_unlock(&conn->chan_lock); 741 } 742 743 EXPORT_SYMBOL_GPL(l2cap_chan_list); 744 745 static void l2cap_conn_update_id_addr(struct work_struct *work) 746 { 747 struct l2cap_conn *conn = container_of(work, struct l2cap_conn, 748 id_addr_timer.work); 749 struct hci_conn *hcon = conn->hcon; 750 struct l2cap_chan *chan; 751 752 mutex_lock(&conn->chan_lock); 753 754 list_for_each_entry(chan, &conn->chan_l, list) { 755 l2cap_chan_lock(chan); 756 bacpy(&chan->dst, &hcon->dst); 757 chan->dst_type = bdaddr_dst_type(hcon); 758 l2cap_chan_unlock(chan); 759 } 760 761 mutex_unlock(&conn->chan_lock); 762 } 763 764 static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan) 765 { 766 struct l2cap_conn *conn = chan->conn; 767 struct l2cap_le_conn_rsp rsp; 768 u16 result; 769 770 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) 771 result = L2CAP_CR_LE_AUTHORIZATION; 772 else 773 result = L2CAP_CR_LE_BAD_PSM; 774 775 l2cap_state_change(chan, BT_DISCONN); 776 777 rsp.dcid = cpu_to_le16(chan->scid); 778 rsp.mtu = cpu_to_le16(chan->imtu); 779 rsp.mps = cpu_to_le16(chan->mps); 780 rsp.credits = cpu_to_le16(chan->rx_credits); 781 rsp.result = cpu_to_le16(result); 782 783 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), 784 &rsp); 785 } 786 787 static void l2cap_chan_ecred_connect_reject(struct l2cap_chan *chan) 788 { 789 l2cap_state_change(chan, BT_DISCONN); 790 791 __l2cap_ecred_conn_rsp_defer(chan); 792 } 793 794 static void l2cap_chan_connect_reject(struct l2cap_chan *chan) 795 { 796 struct l2cap_conn *conn = chan->conn; 797 struct l2cap_conn_rsp rsp; 798 u16 result; 799 800 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) 801 result = L2CAP_CR_SEC_BLOCK; 802 else 803 result = L2CAP_CR_BAD_PSM; 804 805 l2cap_state_change(chan, BT_DISCONN); 806 807 rsp.scid = cpu_to_le16(chan->dcid); 808 rsp.dcid = cpu_to_le16(chan->scid); 809 rsp.result = cpu_to_le16(result); 810 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 811 812 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp); 813 } 814 815 void l2cap_chan_close(struct l2cap_chan *chan, int reason) 816 { 817 struct l2cap_conn *conn = chan->conn; 818 819 BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); 820 821 switch (chan->state) { 822 case BT_LISTEN: 823 chan->ops->teardown(chan, 0); 824 break; 825 826 case BT_CONNECTED: 827 case BT_CONFIG: 828 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) { 829 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 830 l2cap_send_disconn_req(chan, reason); 831 } else 832 l2cap_chan_del(chan, reason); 833 break; 834 835 case BT_CONNECT2: 836 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) { 837 if (conn->hcon->type == ACL_LINK) 838 l2cap_chan_connect_reject(chan); 839 else if (conn->hcon->type == LE_LINK) { 840 switch (chan->mode) { 841 case L2CAP_MODE_LE_FLOWCTL: 842 l2cap_chan_le_connect_reject(chan); 843 break; 844 case L2CAP_MODE_EXT_FLOWCTL: 845 l2cap_chan_ecred_connect_reject(chan); 846 return; 847 } 848 } 849 } 850 851 l2cap_chan_del(chan, reason); 852 break; 853 854 case BT_CONNECT: 855 case BT_DISCONN: 856 l2cap_chan_del(chan, reason); 857 break; 858 859 default: 860 chan->ops->teardown(chan, 0); 861 break; 862 } 863 } 864 EXPORT_SYMBOL(l2cap_chan_close); 865 866 static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan) 867 { 868 switch (chan->chan_type) { 869 case L2CAP_CHAN_RAW: 870 switch (chan->sec_level) { 871 case BT_SECURITY_HIGH: 872 case BT_SECURITY_FIPS: 873 return HCI_AT_DEDICATED_BONDING_MITM; 874 case BT_SECURITY_MEDIUM: 875 return HCI_AT_DEDICATED_BONDING; 876 default: 877 return HCI_AT_NO_BONDING; 878 } 879 break; 880 case L2CAP_CHAN_CONN_LESS: 881 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) { 882 if (chan->sec_level == BT_SECURITY_LOW) 883 chan->sec_level = BT_SECURITY_SDP; 884 } 885 if (chan->sec_level == BT_SECURITY_HIGH || 886 chan->sec_level == BT_SECURITY_FIPS) 887 return HCI_AT_NO_BONDING_MITM; 888 else 889 return HCI_AT_NO_BONDING; 890 break; 891 case L2CAP_CHAN_CONN_ORIENTED: 892 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) { 893 if (chan->sec_level == BT_SECURITY_LOW) 894 chan->sec_level = BT_SECURITY_SDP; 895 896 if (chan->sec_level == BT_SECURITY_HIGH || 897 chan->sec_level == BT_SECURITY_FIPS) 898 return HCI_AT_NO_BONDING_MITM; 899 else 900 return HCI_AT_NO_BONDING; 901 } 902 fallthrough; 903 904 default: 905 switch (chan->sec_level) { 906 case BT_SECURITY_HIGH: 907 case BT_SECURITY_FIPS: 908 return HCI_AT_GENERAL_BONDING_MITM; 909 case BT_SECURITY_MEDIUM: 910 return HCI_AT_GENERAL_BONDING; 911 default: 912 return HCI_AT_NO_BONDING; 913 } 914 break; 915 } 916 } 917 918 /* Service level security */ 919 int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator) 920 { 921 struct l2cap_conn *conn = chan->conn; 922 __u8 auth_type; 923 924 if (conn->hcon->type == LE_LINK) 925 return smp_conn_security(conn->hcon, chan->sec_level); 926 927 auth_type = l2cap_get_auth_type(chan); 928 929 return hci_conn_security(conn->hcon, chan->sec_level, auth_type, 930 initiator); 931 } 932 933 static u8 l2cap_get_ident(struct l2cap_conn *conn) 934 { 935 u8 id; 936 937 /* Get next available identificator. 938 * 1 - 128 are used by kernel. 939 * 129 - 199 are reserved. 940 * 200 - 254 are used by utilities like l2ping, etc. 941 */ 942 943 mutex_lock(&conn->ident_lock); 944 945 if (++conn->tx_ident > 128) 946 conn->tx_ident = 1; 947 948 id = conn->tx_ident; 949 950 mutex_unlock(&conn->ident_lock); 951 952 return id; 953 } 954 955 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, 956 void *data) 957 { 958 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data); 959 u8 flags; 960 961 BT_DBG("code 0x%2.2x", code); 962 963 if (!skb) 964 return; 965 966 /* Use NO_FLUSH if supported or we have an LE link (which does 967 * not support auto-flushing packets) */ 968 if (lmp_no_flush_capable(conn->hcon->hdev) || 969 conn->hcon->type == LE_LINK) 970 flags = ACL_START_NO_FLUSH; 971 else 972 flags = ACL_START; 973 974 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON; 975 skb->priority = HCI_PRIO_MAX; 976 977 hci_send_acl(conn->hchan, skb, flags); 978 } 979 980 static bool __chan_is_moving(struct l2cap_chan *chan) 981 { 982 return chan->move_state != L2CAP_MOVE_STABLE && 983 chan->move_state != L2CAP_MOVE_WAIT_PREPARE; 984 } 985 986 static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb) 987 { 988 struct hci_conn *hcon = chan->conn->hcon; 989 u16 flags; 990 991 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len, 992 skb->priority); 993 994 if (chan->hs_hcon && !__chan_is_moving(chan)) { 995 if (chan->hs_hchan) 996 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE); 997 else 998 kfree_skb(skb); 999 1000 return; 1001 } 1002 1003 /* Use NO_FLUSH for LE links (where this is the only option) or 1004 * if the BR/EDR link supports it and flushing has not been 1005 * explicitly requested (through FLAG_FLUSHABLE). 1006 */ 1007 if (hcon->type == LE_LINK || 1008 (!test_bit(FLAG_FLUSHABLE, &chan->flags) && 1009 lmp_no_flush_capable(hcon->hdev))) 1010 flags = ACL_START_NO_FLUSH; 1011 else 1012 flags = ACL_START; 1013 1014 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags); 1015 hci_send_acl(chan->conn->hchan, skb, flags); 1016 } 1017 1018 static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control) 1019 { 1020 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT; 1021 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT; 1022 1023 if (enh & L2CAP_CTRL_FRAME_TYPE) { 1024 /* S-Frame */ 1025 control->sframe = 1; 1026 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT; 1027 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT; 1028 1029 control->sar = 0; 1030 control->txseq = 0; 1031 } else { 1032 /* I-Frame */ 1033 control->sframe = 0; 1034 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT; 1035 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT; 1036 1037 control->poll = 0; 1038 control->super = 0; 1039 } 1040 } 1041 1042 static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control) 1043 { 1044 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT; 1045 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT; 1046 1047 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) { 1048 /* S-Frame */ 1049 control->sframe = 1; 1050 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT; 1051 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT; 1052 1053 control->sar = 0; 1054 control->txseq = 0; 1055 } else { 1056 /* I-Frame */ 1057 control->sframe = 0; 1058 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT; 1059 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT; 1060 1061 control->poll = 0; 1062 control->super = 0; 1063 } 1064 } 1065 1066 static inline void __unpack_control(struct l2cap_chan *chan, 1067 struct sk_buff *skb) 1068 { 1069 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) { 1070 __unpack_extended_control(get_unaligned_le32(skb->data), 1071 &bt_cb(skb)->l2cap); 1072 skb_pull(skb, L2CAP_EXT_CTRL_SIZE); 1073 } else { 1074 __unpack_enhanced_control(get_unaligned_le16(skb->data), 1075 &bt_cb(skb)->l2cap); 1076 skb_pull(skb, L2CAP_ENH_CTRL_SIZE); 1077 } 1078 } 1079 1080 static u32 __pack_extended_control(struct l2cap_ctrl *control) 1081 { 1082 u32 packed; 1083 1084 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT; 1085 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT; 1086 1087 if (control->sframe) { 1088 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT; 1089 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT; 1090 packed |= L2CAP_EXT_CTRL_FRAME_TYPE; 1091 } else { 1092 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT; 1093 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT; 1094 } 1095 1096 return packed; 1097 } 1098 1099 static u16 __pack_enhanced_control(struct l2cap_ctrl *control) 1100 { 1101 u16 packed; 1102 1103 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT; 1104 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT; 1105 1106 if (control->sframe) { 1107 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT; 1108 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT; 1109 packed |= L2CAP_CTRL_FRAME_TYPE; 1110 } else { 1111 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT; 1112 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT; 1113 } 1114 1115 return packed; 1116 } 1117 1118 static inline void __pack_control(struct l2cap_chan *chan, 1119 struct l2cap_ctrl *control, 1120 struct sk_buff *skb) 1121 { 1122 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) { 1123 put_unaligned_le32(__pack_extended_control(control), 1124 skb->data + L2CAP_HDR_SIZE); 1125 } else { 1126 put_unaligned_le16(__pack_enhanced_control(control), 1127 skb->data + L2CAP_HDR_SIZE); 1128 } 1129 } 1130 1131 static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan) 1132 { 1133 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 1134 return L2CAP_EXT_HDR_SIZE; 1135 else 1136 return L2CAP_ENH_HDR_SIZE; 1137 } 1138 1139 static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan, 1140 u32 control) 1141 { 1142 struct sk_buff *skb; 1143 struct l2cap_hdr *lh; 1144 int hlen = __ertm_hdr_size(chan); 1145 1146 if (chan->fcs == L2CAP_FCS_CRC16) 1147 hlen += L2CAP_FCS_SIZE; 1148 1149 skb = bt_skb_alloc(hlen, GFP_KERNEL); 1150 1151 if (!skb) 1152 return ERR_PTR(-ENOMEM); 1153 1154 lh = skb_put(skb, L2CAP_HDR_SIZE); 1155 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE); 1156 lh->cid = cpu_to_le16(chan->dcid); 1157 1158 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 1159 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE)); 1160 else 1161 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE)); 1162 1163 if (chan->fcs == L2CAP_FCS_CRC16) { 1164 u16 fcs = crc16(0, (u8 *)skb->data, skb->len); 1165 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE)); 1166 } 1167 1168 skb->priority = HCI_PRIO_MAX; 1169 return skb; 1170 } 1171 1172 static void l2cap_send_sframe(struct l2cap_chan *chan, 1173 struct l2cap_ctrl *control) 1174 { 1175 struct sk_buff *skb; 1176 u32 control_field; 1177 1178 BT_DBG("chan %p, control %p", chan, control); 1179 1180 if (!control->sframe) 1181 return; 1182 1183 if (__chan_is_moving(chan)) 1184 return; 1185 1186 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) && 1187 !control->poll) 1188 control->final = 1; 1189 1190 if (control->super == L2CAP_SUPER_RR) 1191 clear_bit(CONN_RNR_SENT, &chan->conn_state); 1192 else if (control->super == L2CAP_SUPER_RNR) 1193 set_bit(CONN_RNR_SENT, &chan->conn_state); 1194 1195 if (control->super != L2CAP_SUPER_SREJ) { 1196 chan->last_acked_seq = control->reqseq; 1197 __clear_ack_timer(chan); 1198 } 1199 1200 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq, 1201 control->final, control->poll, control->super); 1202 1203 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 1204 control_field = __pack_extended_control(control); 1205 else 1206 control_field = __pack_enhanced_control(control); 1207 1208 skb = l2cap_create_sframe_pdu(chan, control_field); 1209 if (!IS_ERR(skb)) 1210 l2cap_do_send(chan, skb); 1211 } 1212 1213 static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll) 1214 { 1215 struct l2cap_ctrl control; 1216 1217 BT_DBG("chan %p, poll %d", chan, poll); 1218 1219 memset(&control, 0, sizeof(control)); 1220 control.sframe = 1; 1221 control.poll = poll; 1222 1223 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) 1224 control.super = L2CAP_SUPER_RNR; 1225 else 1226 control.super = L2CAP_SUPER_RR; 1227 1228 control.reqseq = chan->buffer_seq; 1229 l2cap_send_sframe(chan, &control); 1230 } 1231 1232 static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan) 1233 { 1234 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) 1235 return true; 1236 1237 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state); 1238 } 1239 1240 static bool __amp_capable(struct l2cap_chan *chan) 1241 { 1242 struct l2cap_conn *conn = chan->conn; 1243 struct hci_dev *hdev; 1244 bool amp_available = false; 1245 1246 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP)) 1247 return false; 1248 1249 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP)) 1250 return false; 1251 1252 read_lock(&hci_dev_list_lock); 1253 list_for_each_entry(hdev, &hci_dev_list, list) { 1254 if (hdev->amp_type != AMP_TYPE_BREDR && 1255 test_bit(HCI_UP, &hdev->flags)) { 1256 amp_available = true; 1257 break; 1258 } 1259 } 1260 read_unlock(&hci_dev_list_lock); 1261 1262 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED) 1263 return amp_available; 1264 1265 return false; 1266 } 1267 1268 static bool l2cap_check_efs(struct l2cap_chan *chan) 1269 { 1270 /* Check EFS parameters */ 1271 return true; 1272 } 1273 1274 void l2cap_send_conn_req(struct l2cap_chan *chan) 1275 { 1276 struct l2cap_conn *conn = chan->conn; 1277 struct l2cap_conn_req req; 1278 1279 req.scid = cpu_to_le16(chan->scid); 1280 req.psm = chan->psm; 1281 1282 chan->ident = l2cap_get_ident(conn); 1283 1284 set_bit(CONF_CONNECT_PEND, &chan->conf_state); 1285 1286 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req); 1287 } 1288 1289 static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id) 1290 { 1291 struct l2cap_create_chan_req req; 1292 req.scid = cpu_to_le16(chan->scid); 1293 req.psm = chan->psm; 1294 req.amp_id = amp_id; 1295 1296 chan->ident = l2cap_get_ident(chan->conn); 1297 1298 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ, 1299 sizeof(req), &req); 1300 } 1301 1302 static void l2cap_move_setup(struct l2cap_chan *chan) 1303 { 1304 struct sk_buff *skb; 1305 1306 BT_DBG("chan %p", chan); 1307 1308 if (chan->mode != L2CAP_MODE_ERTM) 1309 return; 1310 1311 __clear_retrans_timer(chan); 1312 __clear_monitor_timer(chan); 1313 __clear_ack_timer(chan); 1314 1315 chan->retry_count = 0; 1316 skb_queue_walk(&chan->tx_q, skb) { 1317 if (bt_cb(skb)->l2cap.retries) 1318 bt_cb(skb)->l2cap.retries = 1; 1319 else 1320 break; 1321 } 1322 1323 chan->expected_tx_seq = chan->buffer_seq; 1324 1325 clear_bit(CONN_REJ_ACT, &chan->conn_state); 1326 clear_bit(CONN_SREJ_ACT, &chan->conn_state); 1327 l2cap_seq_list_clear(&chan->retrans_list); 1328 l2cap_seq_list_clear(&chan->srej_list); 1329 skb_queue_purge(&chan->srej_q); 1330 1331 chan->tx_state = L2CAP_TX_STATE_XMIT; 1332 chan->rx_state = L2CAP_RX_STATE_MOVE; 1333 1334 set_bit(CONN_REMOTE_BUSY, &chan->conn_state); 1335 } 1336 1337 static void l2cap_move_done(struct l2cap_chan *chan) 1338 { 1339 u8 move_role = chan->move_role; 1340 BT_DBG("chan %p", chan); 1341 1342 chan->move_state = L2CAP_MOVE_STABLE; 1343 chan->move_role = L2CAP_MOVE_ROLE_NONE; 1344 1345 if (chan->mode != L2CAP_MODE_ERTM) 1346 return; 1347 1348 switch (move_role) { 1349 case L2CAP_MOVE_ROLE_INITIATOR: 1350 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL); 1351 chan->rx_state = L2CAP_RX_STATE_WAIT_F; 1352 break; 1353 case L2CAP_MOVE_ROLE_RESPONDER: 1354 chan->rx_state = L2CAP_RX_STATE_WAIT_P; 1355 break; 1356 } 1357 } 1358 1359 static void l2cap_chan_ready(struct l2cap_chan *chan) 1360 { 1361 /* The channel may have already been flagged as connected in 1362 * case of receiving data before the L2CAP info req/rsp 1363 * procedure is complete. 1364 */ 1365 if (chan->state == BT_CONNECTED) 1366 return; 1367 1368 /* This clears all conf flags, including CONF_NOT_COMPLETE */ 1369 chan->conf_state = 0; 1370 __clear_chan_timer(chan); 1371 1372 switch (chan->mode) { 1373 case L2CAP_MODE_LE_FLOWCTL: 1374 case L2CAP_MODE_EXT_FLOWCTL: 1375 if (!chan->tx_credits) 1376 chan->ops->suspend(chan); 1377 break; 1378 } 1379 1380 chan->state = BT_CONNECTED; 1381 1382 chan->ops->ready(chan); 1383 } 1384 1385 static void l2cap_le_connect(struct l2cap_chan *chan) 1386 { 1387 struct l2cap_conn *conn = chan->conn; 1388 struct l2cap_le_conn_req req; 1389 1390 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags)) 1391 return; 1392 1393 if (!chan->imtu) 1394 chan->imtu = chan->conn->mtu; 1395 1396 l2cap_le_flowctl_init(chan, 0); 1397 1398 memset(&req, 0, sizeof(req)); 1399 req.psm = chan->psm; 1400 req.scid = cpu_to_le16(chan->scid); 1401 req.mtu = cpu_to_le16(chan->imtu); 1402 req.mps = cpu_to_le16(chan->mps); 1403 req.credits = cpu_to_le16(chan->rx_credits); 1404 1405 chan->ident = l2cap_get_ident(conn); 1406 1407 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ, 1408 sizeof(req), &req); 1409 } 1410 1411 struct l2cap_ecred_conn_data { 1412 struct { 1413 struct l2cap_ecred_conn_req req; 1414 __le16 scid[5]; 1415 } __packed pdu; 1416 struct l2cap_chan *chan; 1417 struct pid *pid; 1418 int count; 1419 }; 1420 1421 static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data) 1422 { 1423 struct l2cap_ecred_conn_data *conn = data; 1424 struct pid *pid; 1425 1426 if (chan == conn->chan) 1427 return; 1428 1429 if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags)) 1430 return; 1431 1432 pid = chan->ops->get_peer_pid(chan); 1433 1434 /* Only add deferred channels with the same PID/PSM */ 1435 if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident || 1436 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT) 1437 return; 1438 1439 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) 1440 return; 1441 1442 l2cap_ecred_init(chan, 0); 1443 1444 /* Set the same ident so we can match on the rsp */ 1445 chan->ident = conn->chan->ident; 1446 1447 /* Include all channels deferred */ 1448 conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid); 1449 1450 conn->count++; 1451 } 1452 1453 static void l2cap_ecred_connect(struct l2cap_chan *chan) 1454 { 1455 struct l2cap_conn *conn = chan->conn; 1456 struct l2cap_ecred_conn_data data; 1457 1458 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) 1459 return; 1460 1461 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) 1462 return; 1463 1464 l2cap_ecred_init(chan, 0); 1465 1466 memset(&data, 0, sizeof(data)); 1467 data.pdu.req.psm = chan->psm; 1468 data.pdu.req.mtu = cpu_to_le16(chan->imtu); 1469 data.pdu.req.mps = cpu_to_le16(chan->mps); 1470 data.pdu.req.credits = cpu_to_le16(chan->rx_credits); 1471 data.pdu.scid[0] = cpu_to_le16(chan->scid); 1472 1473 chan->ident = l2cap_get_ident(conn); 1474 1475 data.count = 1; 1476 data.chan = chan; 1477 data.pid = chan->ops->get_peer_pid(chan); 1478 1479 __l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data); 1480 1481 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ, 1482 sizeof(data.pdu.req) + data.count * sizeof(__le16), 1483 &data.pdu); 1484 } 1485 1486 static void l2cap_le_start(struct l2cap_chan *chan) 1487 { 1488 struct l2cap_conn *conn = chan->conn; 1489 1490 if (!smp_conn_security(conn->hcon, chan->sec_level)) 1491 return; 1492 1493 if (!chan->psm) { 1494 l2cap_chan_ready(chan); 1495 return; 1496 } 1497 1498 if (chan->state == BT_CONNECT) { 1499 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) 1500 l2cap_ecred_connect(chan); 1501 else 1502 l2cap_le_connect(chan); 1503 } 1504 } 1505 1506 static void l2cap_start_connection(struct l2cap_chan *chan) 1507 { 1508 if (__amp_capable(chan)) { 1509 BT_DBG("chan %p AMP capable: discover AMPs", chan); 1510 a2mp_discover_amp(chan); 1511 } else if (chan->conn->hcon->type == LE_LINK) { 1512 l2cap_le_start(chan); 1513 } else { 1514 l2cap_send_conn_req(chan); 1515 } 1516 } 1517 1518 static void l2cap_request_info(struct l2cap_conn *conn) 1519 { 1520 struct l2cap_info_req req; 1521 1522 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) 1523 return; 1524 1525 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK); 1526 1527 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT; 1528 conn->info_ident = l2cap_get_ident(conn); 1529 1530 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT); 1531 1532 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ, 1533 sizeof(req), &req); 1534 } 1535 1536 static bool l2cap_check_enc_key_size(struct hci_conn *hcon) 1537 { 1538 /* The minimum encryption key size needs to be enforced by the 1539 * host stack before establishing any L2CAP connections. The 1540 * specification in theory allows a minimum of 1, but to align 1541 * BR/EDR and LE transports, a minimum of 7 is chosen. 1542 * 1543 * This check might also be called for unencrypted connections 1544 * that have no key size requirements. Ensure that the link is 1545 * actually encrypted before enforcing a key size. 1546 */ 1547 int min_key_size = hcon->hdev->min_enc_key_size; 1548 1549 /* On FIPS security level, key size must be 16 bytes */ 1550 if (hcon->sec_level == BT_SECURITY_FIPS) 1551 min_key_size = 16; 1552 1553 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) || 1554 hcon->enc_key_size >= min_key_size); 1555 } 1556 1557 static void l2cap_do_start(struct l2cap_chan *chan) 1558 { 1559 struct l2cap_conn *conn = chan->conn; 1560 1561 if (conn->hcon->type == LE_LINK) { 1562 l2cap_le_start(chan); 1563 return; 1564 } 1565 1566 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) { 1567 l2cap_request_info(conn); 1568 return; 1569 } 1570 1571 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)) 1572 return; 1573 1574 if (!l2cap_chan_check_security(chan, true) || 1575 !__l2cap_no_conn_pending(chan)) 1576 return; 1577 1578 if (l2cap_check_enc_key_size(conn->hcon)) 1579 l2cap_start_connection(chan); 1580 else 1581 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); 1582 } 1583 1584 static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask) 1585 { 1586 u32 local_feat_mask = l2cap_feat_mask; 1587 if (!disable_ertm) 1588 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING; 1589 1590 switch (mode) { 1591 case L2CAP_MODE_ERTM: 1592 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask; 1593 case L2CAP_MODE_STREAMING: 1594 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask; 1595 default: 1596 return 0x00; 1597 } 1598 } 1599 1600 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err) 1601 { 1602 struct l2cap_conn *conn = chan->conn; 1603 struct l2cap_disconn_req req; 1604 1605 if (!conn) 1606 return; 1607 1608 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) { 1609 __clear_retrans_timer(chan); 1610 __clear_monitor_timer(chan); 1611 __clear_ack_timer(chan); 1612 } 1613 1614 if (chan->scid == L2CAP_CID_A2MP) { 1615 l2cap_state_change(chan, BT_DISCONN); 1616 return; 1617 } 1618 1619 req.dcid = cpu_to_le16(chan->dcid); 1620 req.scid = cpu_to_le16(chan->scid); 1621 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ, 1622 sizeof(req), &req); 1623 1624 l2cap_state_change_and_error(chan, BT_DISCONN, err); 1625 } 1626 1627 /* ---- L2CAP connections ---- */ 1628 static void l2cap_conn_start(struct l2cap_conn *conn) 1629 { 1630 struct l2cap_chan *chan, *tmp; 1631 1632 BT_DBG("conn %p", conn); 1633 1634 mutex_lock(&conn->chan_lock); 1635 1636 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { 1637 l2cap_chan_lock(chan); 1638 1639 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 1640 l2cap_chan_ready(chan); 1641 l2cap_chan_unlock(chan); 1642 continue; 1643 } 1644 1645 if (chan->state == BT_CONNECT) { 1646 if (!l2cap_chan_check_security(chan, true) || 1647 !__l2cap_no_conn_pending(chan)) { 1648 l2cap_chan_unlock(chan); 1649 continue; 1650 } 1651 1652 if (!l2cap_mode_supported(chan->mode, conn->feat_mask) 1653 && test_bit(CONF_STATE2_DEVICE, 1654 &chan->conf_state)) { 1655 l2cap_chan_close(chan, ECONNRESET); 1656 l2cap_chan_unlock(chan); 1657 continue; 1658 } 1659 1660 if (l2cap_check_enc_key_size(conn->hcon)) 1661 l2cap_start_connection(chan); 1662 else 1663 l2cap_chan_close(chan, ECONNREFUSED); 1664 1665 } else if (chan->state == BT_CONNECT2) { 1666 struct l2cap_conn_rsp rsp; 1667 char buf[128]; 1668 rsp.scid = cpu_to_le16(chan->dcid); 1669 rsp.dcid = cpu_to_le16(chan->scid); 1670 1671 if (l2cap_chan_check_security(chan, false)) { 1672 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 1673 rsp.result = cpu_to_le16(L2CAP_CR_PEND); 1674 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND); 1675 chan->ops->defer(chan); 1676 1677 } else { 1678 l2cap_state_change(chan, BT_CONFIG); 1679 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS); 1680 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 1681 } 1682 } else { 1683 rsp.result = cpu_to_le16(L2CAP_CR_PEND); 1684 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND); 1685 } 1686 1687 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, 1688 sizeof(rsp), &rsp); 1689 1690 if (test_bit(CONF_REQ_SENT, &chan->conf_state) || 1691 rsp.result != L2CAP_CR_SUCCESS) { 1692 l2cap_chan_unlock(chan); 1693 continue; 1694 } 1695 1696 set_bit(CONF_REQ_SENT, &chan->conf_state); 1697 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 1698 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 1699 chan->num_conf_req++; 1700 } 1701 1702 l2cap_chan_unlock(chan); 1703 } 1704 1705 mutex_unlock(&conn->chan_lock); 1706 } 1707 1708 static void l2cap_le_conn_ready(struct l2cap_conn *conn) 1709 { 1710 struct hci_conn *hcon = conn->hcon; 1711 struct hci_dev *hdev = hcon->hdev; 1712 1713 BT_DBG("%s conn %p", hdev->name, conn); 1714 1715 /* For outgoing pairing which doesn't necessarily have an 1716 * associated socket (e.g. mgmt_pair_device). 1717 */ 1718 if (hcon->out) 1719 smp_conn_security(hcon, hcon->pending_sec_level); 1720 1721 /* For LE peripheral connections, make sure the connection interval 1722 * is in the range of the minimum and maximum interval that has 1723 * been configured for this connection. If not, then trigger 1724 * the connection update procedure. 1725 */ 1726 if (hcon->role == HCI_ROLE_SLAVE && 1727 (hcon->le_conn_interval < hcon->le_conn_min_interval || 1728 hcon->le_conn_interval > hcon->le_conn_max_interval)) { 1729 struct l2cap_conn_param_update_req req; 1730 1731 req.min = cpu_to_le16(hcon->le_conn_min_interval); 1732 req.max = cpu_to_le16(hcon->le_conn_max_interval); 1733 req.latency = cpu_to_le16(hcon->le_conn_latency); 1734 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout); 1735 1736 l2cap_send_cmd(conn, l2cap_get_ident(conn), 1737 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req); 1738 } 1739 } 1740 1741 static void l2cap_conn_ready(struct l2cap_conn *conn) 1742 { 1743 struct l2cap_chan *chan; 1744 struct hci_conn *hcon = conn->hcon; 1745 1746 BT_DBG("conn %p", conn); 1747 1748 if (hcon->type == ACL_LINK) 1749 l2cap_request_info(conn); 1750 1751 mutex_lock(&conn->chan_lock); 1752 1753 list_for_each_entry(chan, &conn->chan_l, list) { 1754 1755 l2cap_chan_lock(chan); 1756 1757 if (chan->scid == L2CAP_CID_A2MP) { 1758 l2cap_chan_unlock(chan); 1759 continue; 1760 } 1761 1762 if (hcon->type == LE_LINK) { 1763 l2cap_le_start(chan); 1764 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 1765 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) 1766 l2cap_chan_ready(chan); 1767 } else if (chan->state == BT_CONNECT) { 1768 l2cap_do_start(chan); 1769 } 1770 1771 l2cap_chan_unlock(chan); 1772 } 1773 1774 mutex_unlock(&conn->chan_lock); 1775 1776 if (hcon->type == LE_LINK) 1777 l2cap_le_conn_ready(conn); 1778 1779 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work); 1780 } 1781 1782 /* Notify sockets that we cannot guaranty reliability anymore */ 1783 static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err) 1784 { 1785 struct l2cap_chan *chan; 1786 1787 BT_DBG("conn %p", conn); 1788 1789 mutex_lock(&conn->chan_lock); 1790 1791 list_for_each_entry(chan, &conn->chan_l, list) { 1792 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags)) 1793 l2cap_chan_set_err(chan, err); 1794 } 1795 1796 mutex_unlock(&conn->chan_lock); 1797 } 1798 1799 static void l2cap_info_timeout(struct work_struct *work) 1800 { 1801 struct l2cap_conn *conn = container_of(work, struct l2cap_conn, 1802 info_timer.work); 1803 1804 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 1805 conn->info_ident = 0; 1806 1807 l2cap_conn_start(conn); 1808 } 1809 1810 /* 1811 * l2cap_user 1812 * External modules can register l2cap_user objects on l2cap_conn. The ->probe 1813 * callback is called during registration. The ->remove callback is called 1814 * during unregistration. 1815 * An l2cap_user object can either be explicitly unregistered or when the 1816 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon, 1817 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called. 1818 * External modules must own a reference to the l2cap_conn object if they intend 1819 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at 1820 * any time if they don't. 1821 */ 1822 1823 int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user) 1824 { 1825 struct hci_dev *hdev = conn->hcon->hdev; 1826 int ret; 1827 1828 /* We need to check whether l2cap_conn is registered. If it is not, we 1829 * must not register the l2cap_user. l2cap_conn_del() is unregisters 1830 * l2cap_conn objects, but doesn't provide its own locking. Instead, it 1831 * relies on the parent hci_conn object to be locked. This itself relies 1832 * on the hci_dev object to be locked. So we must lock the hci device 1833 * here, too. */ 1834 1835 hci_dev_lock(hdev); 1836 1837 if (!list_empty(&user->list)) { 1838 ret = -EINVAL; 1839 goto out_unlock; 1840 } 1841 1842 /* conn->hchan is NULL after l2cap_conn_del() was called */ 1843 if (!conn->hchan) { 1844 ret = -ENODEV; 1845 goto out_unlock; 1846 } 1847 1848 ret = user->probe(conn, user); 1849 if (ret) 1850 goto out_unlock; 1851 1852 list_add(&user->list, &conn->users); 1853 ret = 0; 1854 1855 out_unlock: 1856 hci_dev_unlock(hdev); 1857 return ret; 1858 } 1859 EXPORT_SYMBOL(l2cap_register_user); 1860 1861 void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user) 1862 { 1863 struct hci_dev *hdev = conn->hcon->hdev; 1864 1865 hci_dev_lock(hdev); 1866 1867 if (list_empty(&user->list)) 1868 goto out_unlock; 1869 1870 list_del_init(&user->list); 1871 user->remove(conn, user); 1872 1873 out_unlock: 1874 hci_dev_unlock(hdev); 1875 } 1876 EXPORT_SYMBOL(l2cap_unregister_user); 1877 1878 static void l2cap_unregister_all_users(struct l2cap_conn *conn) 1879 { 1880 struct l2cap_user *user; 1881 1882 while (!list_empty(&conn->users)) { 1883 user = list_first_entry(&conn->users, struct l2cap_user, list); 1884 list_del_init(&user->list); 1885 user->remove(conn, user); 1886 } 1887 } 1888 1889 static void l2cap_conn_del(struct hci_conn *hcon, int err) 1890 { 1891 struct l2cap_conn *conn = hcon->l2cap_data; 1892 struct l2cap_chan *chan, *l; 1893 1894 if (!conn) 1895 return; 1896 1897 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err); 1898 1899 kfree_skb(conn->rx_skb); 1900 1901 skb_queue_purge(&conn->pending_rx); 1902 1903 /* We can not call flush_work(&conn->pending_rx_work) here since we 1904 * might block if we are running on a worker from the same workqueue 1905 * pending_rx_work is waiting on. 1906 */ 1907 if (work_pending(&conn->pending_rx_work)) 1908 cancel_work_sync(&conn->pending_rx_work); 1909 1910 cancel_delayed_work_sync(&conn->id_addr_timer); 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 1944 static 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 1952 struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn) 1953 { 1954 kref_get(&conn->ref); 1955 return conn; 1956 } 1957 EXPORT_SYMBOL(l2cap_conn_get); 1958 1959 void l2cap_conn_put(struct l2cap_conn *conn) 1960 { 1961 kref_put(&conn->ref, l2cap_conn_free); 1962 } 1963 EXPORT_SYMBOL(l2cap_conn_put); 1964 1965 /* ---- Socket interface ---- */ 1966 1967 /* Find socket with psm and source / destination bdaddr. 1968 * Returns closest match. 1969 */ 1970 static 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 2021 static 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 2042 static 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 2062 static 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 2101 static 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 2171 static 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 2252 static 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 2261 static 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 2295 static 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 2345 static 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 2389 static 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 2421 static 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 2451 static 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 2505 static 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 2572 static 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 2615 static 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 2651 static 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 2667 int 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 } 2769 EXPORT_SYMBOL_GPL(l2cap_chan_send); 2770 2771 static 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 2794 static 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 2810 static 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 2836 static 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 2868 static 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 2878 static 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 2950 static 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 3027 static 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 3046 static 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 3053 static 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 */ 3061 static 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 ---- */ 3089 static 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 3150 fail: 3151 kfree_skb(skb); 3152 return NULL; 3153 } 3154 3155 static 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 3189 static 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 3222 static 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 3253 static 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 3273 int 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 3314 static 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 3327 static 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 3333 static 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 3339 static 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 3377 static 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 3392 static 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 3435 static 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 3463 done: 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 3561 static 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 l2cap_add_conf_opt(&ptr, (u8)type, sizeof(u8), type, endptr - ptr); 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 3668 done: 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 3787 static 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 3905 static 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 3920 void __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 3937 static 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 3958 struct 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 3966 static 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 3983 void __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 4019 void __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 4048 static 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 4104 static 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 4129 static 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 4235 response: 4236 l2cap_chan_unlock(pchan); 4237 mutex_unlock(&conn->chan_lock); 4238 l2cap_chan_put(pchan); 4239 4240 sendresp: 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 4272 static 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, NULL, 0); 4285 hci_dev_unlock(hdev); 4286 4287 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0); 4288 return 0; 4289 } 4290 4291 static 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 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x", 4310 dcid, scid, result, status); 4311 4312 mutex_lock(&conn->chan_lock); 4313 4314 if (scid) { 4315 chan = __l2cap_get_chan_by_scid(conn, scid); 4316 if (!chan) { 4317 err = -EBADSLT; 4318 goto unlock; 4319 } 4320 } else { 4321 chan = __l2cap_get_chan_by_ident(conn, cmd->ident); 4322 if (!chan) { 4323 err = -EBADSLT; 4324 goto unlock; 4325 } 4326 } 4327 4328 chan = l2cap_chan_hold_unless_zero(chan); 4329 if (!chan) { 4330 err = -EBADSLT; 4331 goto unlock; 4332 } 4333 4334 err = 0; 4335 4336 l2cap_chan_lock(chan); 4337 4338 switch (result) { 4339 case L2CAP_CR_SUCCESS: 4340 l2cap_state_change(chan, BT_CONFIG); 4341 chan->ident = 0; 4342 chan->dcid = dcid; 4343 clear_bit(CONF_CONNECT_PEND, &chan->conf_state); 4344 4345 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) 4346 break; 4347 4348 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 4349 l2cap_build_conf_req(chan, req, sizeof(req)), req); 4350 chan->num_conf_req++; 4351 break; 4352 4353 case L2CAP_CR_PEND: 4354 set_bit(CONF_CONNECT_PEND, &chan->conf_state); 4355 break; 4356 4357 default: 4358 l2cap_chan_del(chan, ECONNREFUSED); 4359 break; 4360 } 4361 4362 l2cap_chan_unlock(chan); 4363 l2cap_chan_put(chan); 4364 4365 unlock: 4366 mutex_unlock(&conn->chan_lock); 4367 4368 return err; 4369 } 4370 4371 static inline void set_default_fcs(struct l2cap_chan *chan) 4372 { 4373 /* FCS is enabled only in ERTM or streaming mode, if one or both 4374 * sides request it. 4375 */ 4376 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING) 4377 chan->fcs = L2CAP_FCS_NONE; 4378 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) 4379 chan->fcs = L2CAP_FCS_CRC16; 4380 } 4381 4382 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data, 4383 u8 ident, u16 flags) 4384 { 4385 struct l2cap_conn *conn = chan->conn; 4386 4387 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident, 4388 flags); 4389 4390 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state); 4391 set_bit(CONF_OUTPUT_DONE, &chan->conf_state); 4392 4393 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP, 4394 l2cap_build_conf_rsp(chan, data, 4395 L2CAP_CONF_SUCCESS, flags), data); 4396 } 4397 4398 static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident, 4399 u16 scid, u16 dcid) 4400 { 4401 struct l2cap_cmd_rej_cid rej; 4402 4403 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID); 4404 rej.scid = __cpu_to_le16(scid); 4405 rej.dcid = __cpu_to_le16(dcid); 4406 4407 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej); 4408 } 4409 4410 static inline int l2cap_config_req(struct l2cap_conn *conn, 4411 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4412 u8 *data) 4413 { 4414 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data; 4415 u16 dcid, flags; 4416 u8 rsp[64]; 4417 struct l2cap_chan *chan; 4418 int len, err = 0; 4419 4420 if (cmd_len < sizeof(*req)) 4421 return -EPROTO; 4422 4423 dcid = __le16_to_cpu(req->dcid); 4424 flags = __le16_to_cpu(req->flags); 4425 4426 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags); 4427 4428 chan = l2cap_get_chan_by_scid(conn, dcid); 4429 if (!chan) { 4430 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0); 4431 return 0; 4432 } 4433 4434 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2 && 4435 chan->state != BT_CONNECTED) { 4436 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid, 4437 chan->dcid); 4438 goto unlock; 4439 } 4440 4441 /* Reject if config buffer is too small. */ 4442 len = cmd_len - sizeof(*req); 4443 if (chan->conf_len + len > sizeof(chan->conf_req)) { 4444 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, 4445 l2cap_build_conf_rsp(chan, rsp, 4446 L2CAP_CONF_REJECT, flags), rsp); 4447 goto unlock; 4448 } 4449 4450 /* Store config. */ 4451 memcpy(chan->conf_req + chan->conf_len, req->data, len); 4452 chan->conf_len += len; 4453 4454 if (flags & L2CAP_CONF_FLAG_CONTINUATION) { 4455 /* Incomplete config. Send empty response. */ 4456 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, 4457 l2cap_build_conf_rsp(chan, rsp, 4458 L2CAP_CONF_SUCCESS, flags), rsp); 4459 goto unlock; 4460 } 4461 4462 /* Complete config. */ 4463 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp)); 4464 if (len < 0) { 4465 l2cap_send_disconn_req(chan, ECONNRESET); 4466 goto unlock; 4467 } 4468 4469 chan->ident = cmd->ident; 4470 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp); 4471 if (chan->num_conf_rsp < L2CAP_CONF_MAX_CONF_RSP) 4472 chan->num_conf_rsp++; 4473 4474 /* Reset config buffer. */ 4475 chan->conf_len = 0; 4476 4477 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) 4478 goto unlock; 4479 4480 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) { 4481 set_default_fcs(chan); 4482 4483 if (chan->mode == L2CAP_MODE_ERTM || 4484 chan->mode == L2CAP_MODE_STREAMING) 4485 err = l2cap_ertm_init(chan); 4486 4487 if (err < 0) 4488 l2cap_send_disconn_req(chan, -err); 4489 else 4490 l2cap_chan_ready(chan); 4491 4492 goto unlock; 4493 } 4494 4495 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) { 4496 u8 buf[64]; 4497 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, 4498 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 4499 chan->num_conf_req++; 4500 } 4501 4502 /* Got Conf Rsp PENDING from remote side and assume we sent 4503 Conf Rsp PENDING in the code above */ 4504 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) && 4505 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) { 4506 4507 /* check compatibility */ 4508 4509 /* Send rsp for BR/EDR channel */ 4510 if (!chan->hs_hcon) 4511 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags); 4512 else 4513 chan->ident = cmd->ident; 4514 } 4515 4516 unlock: 4517 l2cap_chan_unlock(chan); 4518 l2cap_chan_put(chan); 4519 return err; 4520 } 4521 4522 static inline int l2cap_config_rsp(struct l2cap_conn *conn, 4523 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4524 u8 *data) 4525 { 4526 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data; 4527 u16 scid, flags, result; 4528 struct l2cap_chan *chan; 4529 int len = cmd_len - sizeof(*rsp); 4530 int err = 0; 4531 4532 if (cmd_len < sizeof(*rsp)) 4533 return -EPROTO; 4534 4535 scid = __le16_to_cpu(rsp->scid); 4536 flags = __le16_to_cpu(rsp->flags); 4537 result = __le16_to_cpu(rsp->result); 4538 4539 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags, 4540 result, len); 4541 4542 chan = l2cap_get_chan_by_scid(conn, scid); 4543 if (!chan) 4544 return 0; 4545 4546 switch (result) { 4547 case L2CAP_CONF_SUCCESS: 4548 l2cap_conf_rfc_get(chan, rsp->data, len); 4549 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state); 4550 break; 4551 4552 case L2CAP_CONF_PENDING: 4553 set_bit(CONF_REM_CONF_PEND, &chan->conf_state); 4554 4555 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) { 4556 char buf[64]; 4557 4558 len = l2cap_parse_conf_rsp(chan, rsp->data, len, 4559 buf, sizeof(buf), &result); 4560 if (len < 0) { 4561 l2cap_send_disconn_req(chan, ECONNRESET); 4562 goto done; 4563 } 4564 4565 if (!chan->hs_hcon) { 4566 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident, 4567 0); 4568 } else { 4569 if (l2cap_check_efs(chan)) { 4570 amp_create_logical_link(chan); 4571 chan->ident = cmd->ident; 4572 } 4573 } 4574 } 4575 goto done; 4576 4577 case L2CAP_CONF_UNKNOWN: 4578 case L2CAP_CONF_UNACCEPT: 4579 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) { 4580 char req[64]; 4581 4582 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) { 4583 l2cap_send_disconn_req(chan, ECONNRESET); 4584 goto done; 4585 } 4586 4587 /* throw out any old stored conf requests */ 4588 result = L2CAP_CONF_SUCCESS; 4589 len = l2cap_parse_conf_rsp(chan, rsp->data, len, 4590 req, sizeof(req), &result); 4591 if (len < 0) { 4592 l2cap_send_disconn_req(chan, ECONNRESET); 4593 goto done; 4594 } 4595 4596 l2cap_send_cmd(conn, l2cap_get_ident(conn), 4597 L2CAP_CONF_REQ, len, req); 4598 chan->num_conf_req++; 4599 if (result != L2CAP_CONF_SUCCESS) 4600 goto done; 4601 break; 4602 } 4603 fallthrough; 4604 4605 default: 4606 l2cap_chan_set_err(chan, ECONNRESET); 4607 4608 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT); 4609 l2cap_send_disconn_req(chan, ECONNRESET); 4610 goto done; 4611 } 4612 4613 if (flags & L2CAP_CONF_FLAG_CONTINUATION) 4614 goto done; 4615 4616 set_bit(CONF_INPUT_DONE, &chan->conf_state); 4617 4618 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) { 4619 set_default_fcs(chan); 4620 4621 if (chan->mode == L2CAP_MODE_ERTM || 4622 chan->mode == L2CAP_MODE_STREAMING) 4623 err = l2cap_ertm_init(chan); 4624 4625 if (err < 0) 4626 l2cap_send_disconn_req(chan, -err); 4627 else 4628 l2cap_chan_ready(chan); 4629 } 4630 4631 done: 4632 l2cap_chan_unlock(chan); 4633 l2cap_chan_put(chan); 4634 return err; 4635 } 4636 4637 static inline int l2cap_disconnect_req(struct l2cap_conn *conn, 4638 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4639 u8 *data) 4640 { 4641 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data; 4642 struct l2cap_disconn_rsp rsp; 4643 u16 dcid, scid; 4644 struct l2cap_chan *chan; 4645 4646 if (cmd_len != sizeof(*req)) 4647 return -EPROTO; 4648 4649 scid = __le16_to_cpu(req->scid); 4650 dcid = __le16_to_cpu(req->dcid); 4651 4652 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid); 4653 4654 chan = l2cap_get_chan_by_scid(conn, dcid); 4655 if (!chan) { 4656 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid); 4657 return 0; 4658 } 4659 4660 rsp.dcid = cpu_to_le16(chan->scid); 4661 rsp.scid = cpu_to_le16(chan->dcid); 4662 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp); 4663 4664 chan->ops->set_shutdown(chan); 4665 4666 mutex_lock(&conn->chan_lock); 4667 l2cap_chan_del(chan, ECONNRESET); 4668 mutex_unlock(&conn->chan_lock); 4669 4670 chan->ops->close(chan); 4671 4672 l2cap_chan_unlock(chan); 4673 l2cap_chan_put(chan); 4674 4675 return 0; 4676 } 4677 4678 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, 4679 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4680 u8 *data) 4681 { 4682 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data; 4683 u16 dcid, scid; 4684 struct l2cap_chan *chan; 4685 4686 if (cmd_len != sizeof(*rsp)) 4687 return -EPROTO; 4688 4689 scid = __le16_to_cpu(rsp->scid); 4690 dcid = __le16_to_cpu(rsp->dcid); 4691 4692 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid); 4693 4694 chan = l2cap_get_chan_by_scid(conn, scid); 4695 if (!chan) { 4696 return 0; 4697 } 4698 4699 if (chan->state != BT_DISCONN) { 4700 l2cap_chan_unlock(chan); 4701 l2cap_chan_put(chan); 4702 return 0; 4703 } 4704 4705 mutex_lock(&conn->chan_lock); 4706 l2cap_chan_del(chan, 0); 4707 mutex_unlock(&conn->chan_lock); 4708 4709 chan->ops->close(chan); 4710 4711 l2cap_chan_unlock(chan); 4712 l2cap_chan_put(chan); 4713 4714 return 0; 4715 } 4716 4717 static inline int l2cap_information_req(struct l2cap_conn *conn, 4718 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4719 u8 *data) 4720 { 4721 struct l2cap_info_req *req = (struct l2cap_info_req *) data; 4722 u16 type; 4723 4724 if (cmd_len != sizeof(*req)) 4725 return -EPROTO; 4726 4727 type = __le16_to_cpu(req->type); 4728 4729 BT_DBG("type 0x%4.4x", type); 4730 4731 if (type == L2CAP_IT_FEAT_MASK) { 4732 u8 buf[8]; 4733 u32 feat_mask = l2cap_feat_mask; 4734 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf; 4735 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK); 4736 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS); 4737 if (!disable_ertm) 4738 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING 4739 | L2CAP_FEAT_FCS; 4740 if (conn->local_fixed_chan & L2CAP_FC_A2MP) 4741 feat_mask |= L2CAP_FEAT_EXT_FLOW 4742 | L2CAP_FEAT_EXT_WINDOW; 4743 4744 put_unaligned_le32(feat_mask, rsp->data); 4745 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf), 4746 buf); 4747 } else if (type == L2CAP_IT_FIXED_CHAN) { 4748 u8 buf[12]; 4749 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf; 4750 4751 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN); 4752 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS); 4753 rsp->data[0] = conn->local_fixed_chan; 4754 memset(rsp->data + 1, 0, 7); 4755 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf), 4756 buf); 4757 } else { 4758 struct l2cap_info_rsp rsp; 4759 rsp.type = cpu_to_le16(type); 4760 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP); 4761 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp), 4762 &rsp); 4763 } 4764 4765 return 0; 4766 } 4767 4768 static inline int l2cap_information_rsp(struct l2cap_conn *conn, 4769 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 4770 u8 *data) 4771 { 4772 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data; 4773 u16 type, result; 4774 4775 if (cmd_len < sizeof(*rsp)) 4776 return -EPROTO; 4777 4778 type = __le16_to_cpu(rsp->type); 4779 result = __le16_to_cpu(rsp->result); 4780 4781 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result); 4782 4783 /* L2CAP Info req/rsp are unbound to channels, add extra checks */ 4784 if (cmd->ident != conn->info_ident || 4785 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) 4786 return 0; 4787 4788 cancel_delayed_work(&conn->info_timer); 4789 4790 if (result != L2CAP_IR_SUCCESS) { 4791 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 4792 conn->info_ident = 0; 4793 4794 l2cap_conn_start(conn); 4795 4796 return 0; 4797 } 4798 4799 switch (type) { 4800 case L2CAP_IT_FEAT_MASK: 4801 conn->feat_mask = get_unaligned_le32(rsp->data); 4802 4803 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) { 4804 struct l2cap_info_req req; 4805 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN); 4806 4807 conn->info_ident = l2cap_get_ident(conn); 4808 4809 l2cap_send_cmd(conn, conn->info_ident, 4810 L2CAP_INFO_REQ, sizeof(req), &req); 4811 } else { 4812 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 4813 conn->info_ident = 0; 4814 4815 l2cap_conn_start(conn); 4816 } 4817 break; 4818 4819 case L2CAP_IT_FIXED_CHAN: 4820 conn->remote_fixed_chan = rsp->data[0]; 4821 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; 4822 conn->info_ident = 0; 4823 4824 l2cap_conn_start(conn); 4825 break; 4826 } 4827 4828 return 0; 4829 } 4830 4831 static int l2cap_create_channel_req(struct l2cap_conn *conn, 4832 struct l2cap_cmd_hdr *cmd, 4833 u16 cmd_len, void *data) 4834 { 4835 struct l2cap_create_chan_req *req = data; 4836 struct l2cap_create_chan_rsp rsp; 4837 struct l2cap_chan *chan; 4838 struct hci_dev *hdev; 4839 u16 psm, scid; 4840 4841 if (cmd_len != sizeof(*req)) 4842 return -EPROTO; 4843 4844 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP)) 4845 return -EINVAL; 4846 4847 psm = le16_to_cpu(req->psm); 4848 scid = le16_to_cpu(req->scid); 4849 4850 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id); 4851 4852 /* For controller id 0 make BR/EDR connection */ 4853 if (req->amp_id == AMP_ID_BREDR) { 4854 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP, 4855 req->amp_id); 4856 return 0; 4857 } 4858 4859 /* Validate AMP controller id */ 4860 hdev = hci_dev_get(req->amp_id); 4861 if (!hdev) 4862 goto error; 4863 4864 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) { 4865 hci_dev_put(hdev); 4866 goto error; 4867 } 4868 4869 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP, 4870 req->amp_id); 4871 if (chan) { 4872 struct amp_mgr *mgr = conn->hcon->amp_mgr; 4873 struct hci_conn *hs_hcon; 4874 4875 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK, 4876 &conn->hcon->dst); 4877 if (!hs_hcon) { 4878 hci_dev_put(hdev); 4879 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid, 4880 chan->dcid); 4881 return 0; 4882 } 4883 4884 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon); 4885 4886 mgr->bredr_chan = chan; 4887 chan->hs_hcon = hs_hcon; 4888 chan->fcs = L2CAP_FCS_NONE; 4889 conn->mtu = hdev->block_mtu; 4890 } 4891 4892 hci_dev_put(hdev); 4893 4894 return 0; 4895 4896 error: 4897 rsp.dcid = 0; 4898 rsp.scid = cpu_to_le16(scid); 4899 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP); 4900 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 4901 4902 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP, 4903 sizeof(rsp), &rsp); 4904 4905 return 0; 4906 } 4907 4908 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id) 4909 { 4910 struct l2cap_move_chan_req req; 4911 u8 ident; 4912 4913 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id); 4914 4915 ident = l2cap_get_ident(chan->conn); 4916 chan->ident = ident; 4917 4918 req.icid = cpu_to_le16(chan->scid); 4919 req.dest_amp_id = dest_amp_id; 4920 4921 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req), 4922 &req); 4923 4924 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT); 4925 } 4926 4927 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result) 4928 { 4929 struct l2cap_move_chan_rsp rsp; 4930 4931 BT_DBG("chan %p, result 0x%4.4x", chan, result); 4932 4933 rsp.icid = cpu_to_le16(chan->dcid); 4934 rsp.result = cpu_to_le16(result); 4935 4936 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP, 4937 sizeof(rsp), &rsp); 4938 } 4939 4940 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result) 4941 { 4942 struct l2cap_move_chan_cfm cfm; 4943 4944 BT_DBG("chan %p, result 0x%4.4x", chan, result); 4945 4946 chan->ident = l2cap_get_ident(chan->conn); 4947 4948 cfm.icid = cpu_to_le16(chan->scid); 4949 cfm.result = cpu_to_le16(result); 4950 4951 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM, 4952 sizeof(cfm), &cfm); 4953 4954 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT); 4955 } 4956 4957 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid) 4958 { 4959 struct l2cap_move_chan_cfm cfm; 4960 4961 BT_DBG("conn %p, icid 0x%4.4x", conn, icid); 4962 4963 cfm.icid = cpu_to_le16(icid); 4964 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED); 4965 4966 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM, 4967 sizeof(cfm), &cfm); 4968 } 4969 4970 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident, 4971 u16 icid) 4972 { 4973 struct l2cap_move_chan_cfm_rsp rsp; 4974 4975 BT_DBG("icid 0x%4.4x", icid); 4976 4977 rsp.icid = cpu_to_le16(icid); 4978 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp); 4979 } 4980 4981 static void __release_logical_link(struct l2cap_chan *chan) 4982 { 4983 chan->hs_hchan = NULL; 4984 chan->hs_hcon = NULL; 4985 4986 /* Placeholder - release the logical link */ 4987 } 4988 4989 static void l2cap_logical_fail(struct l2cap_chan *chan) 4990 { 4991 /* Logical link setup failed */ 4992 if (chan->state != BT_CONNECTED) { 4993 /* Create channel failure, disconnect */ 4994 l2cap_send_disconn_req(chan, ECONNRESET); 4995 return; 4996 } 4997 4998 switch (chan->move_role) { 4999 case L2CAP_MOVE_ROLE_RESPONDER: 5000 l2cap_move_done(chan); 5001 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP); 5002 break; 5003 case L2CAP_MOVE_ROLE_INITIATOR: 5004 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP || 5005 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) { 5006 /* Remote has only sent pending or 5007 * success responses, clean up 5008 */ 5009 l2cap_move_done(chan); 5010 } 5011 5012 /* Other amp move states imply that the move 5013 * has already aborted 5014 */ 5015 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5016 break; 5017 } 5018 } 5019 5020 static void l2cap_logical_finish_create(struct l2cap_chan *chan, 5021 struct hci_chan *hchan) 5022 { 5023 struct l2cap_conf_rsp rsp; 5024 5025 chan->hs_hchan = hchan; 5026 chan->hs_hcon->l2cap_data = chan->conn; 5027 5028 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0); 5029 5030 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) { 5031 int err; 5032 5033 set_default_fcs(chan); 5034 5035 err = l2cap_ertm_init(chan); 5036 if (err < 0) 5037 l2cap_send_disconn_req(chan, -err); 5038 else 5039 l2cap_chan_ready(chan); 5040 } 5041 } 5042 5043 static void l2cap_logical_finish_move(struct l2cap_chan *chan, 5044 struct hci_chan *hchan) 5045 { 5046 chan->hs_hcon = hchan->conn; 5047 chan->hs_hcon->l2cap_data = chan->conn; 5048 5049 BT_DBG("move_state %d", chan->move_state); 5050 5051 switch (chan->move_state) { 5052 case L2CAP_MOVE_WAIT_LOGICAL_COMP: 5053 /* Move confirm will be sent after a success 5054 * response is received 5055 */ 5056 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS; 5057 break; 5058 case L2CAP_MOVE_WAIT_LOGICAL_CFM: 5059 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 5060 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY; 5061 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) { 5062 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP; 5063 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED); 5064 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) { 5065 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM; 5066 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS); 5067 } 5068 break; 5069 default: 5070 /* Move was not in expected state, free the channel */ 5071 __release_logical_link(chan); 5072 5073 chan->move_state = L2CAP_MOVE_STABLE; 5074 } 5075 } 5076 5077 /* Call with chan locked */ 5078 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan, 5079 u8 status) 5080 { 5081 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status); 5082 5083 if (status) { 5084 l2cap_logical_fail(chan); 5085 __release_logical_link(chan); 5086 return; 5087 } 5088 5089 if (chan->state != BT_CONNECTED) { 5090 /* Ignore logical link if channel is on BR/EDR */ 5091 if (chan->local_amp_id != AMP_ID_BREDR) 5092 l2cap_logical_finish_create(chan, hchan); 5093 } else { 5094 l2cap_logical_finish_move(chan, hchan); 5095 } 5096 } 5097 5098 void l2cap_move_start(struct l2cap_chan *chan) 5099 { 5100 BT_DBG("chan %p", chan); 5101 5102 if (chan->local_amp_id == AMP_ID_BREDR) { 5103 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED) 5104 return; 5105 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR; 5106 chan->move_state = L2CAP_MOVE_WAIT_PREPARE; 5107 /* Placeholder - start physical link setup */ 5108 } else { 5109 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR; 5110 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS; 5111 chan->move_id = 0; 5112 l2cap_move_setup(chan); 5113 l2cap_send_move_chan_req(chan, 0); 5114 } 5115 } 5116 5117 static void l2cap_do_create(struct l2cap_chan *chan, int result, 5118 u8 local_amp_id, u8 remote_amp_id) 5119 { 5120 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state), 5121 local_amp_id, remote_amp_id); 5122 5123 chan->fcs = L2CAP_FCS_NONE; 5124 5125 /* Outgoing channel on AMP */ 5126 if (chan->state == BT_CONNECT) { 5127 if (result == L2CAP_CR_SUCCESS) { 5128 chan->local_amp_id = local_amp_id; 5129 l2cap_send_create_chan_req(chan, remote_amp_id); 5130 } else { 5131 /* Revert to BR/EDR connect */ 5132 l2cap_send_conn_req(chan); 5133 } 5134 5135 return; 5136 } 5137 5138 /* Incoming channel on AMP */ 5139 if (__l2cap_no_conn_pending(chan)) { 5140 struct l2cap_conn_rsp rsp; 5141 char buf[128]; 5142 rsp.scid = cpu_to_le16(chan->dcid); 5143 rsp.dcid = cpu_to_le16(chan->scid); 5144 5145 if (result == L2CAP_CR_SUCCESS) { 5146 /* Send successful response */ 5147 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS); 5148 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 5149 } else { 5150 /* Send negative response */ 5151 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM); 5152 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO); 5153 } 5154 5155 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP, 5156 sizeof(rsp), &rsp); 5157 5158 if (result == L2CAP_CR_SUCCESS) { 5159 l2cap_state_change(chan, BT_CONFIG); 5160 set_bit(CONF_REQ_SENT, &chan->conf_state); 5161 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn), 5162 L2CAP_CONF_REQ, 5163 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); 5164 chan->num_conf_req++; 5165 } 5166 } 5167 } 5168 5169 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id, 5170 u8 remote_amp_id) 5171 { 5172 l2cap_move_setup(chan); 5173 chan->move_id = local_amp_id; 5174 chan->move_state = L2CAP_MOVE_WAIT_RSP; 5175 5176 l2cap_send_move_chan_req(chan, remote_amp_id); 5177 } 5178 5179 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result) 5180 { 5181 struct hci_chan *hchan = NULL; 5182 5183 /* Placeholder - get hci_chan for logical link */ 5184 5185 if (hchan) { 5186 if (hchan->state == BT_CONNECTED) { 5187 /* Logical link is ready to go */ 5188 chan->hs_hcon = hchan->conn; 5189 chan->hs_hcon->l2cap_data = chan->conn; 5190 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM; 5191 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS); 5192 5193 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS); 5194 } else { 5195 /* Wait for logical link to be ready */ 5196 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM; 5197 } 5198 } else { 5199 /* Logical link not available */ 5200 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED); 5201 } 5202 } 5203 5204 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result) 5205 { 5206 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) { 5207 u8 rsp_result; 5208 if (result == -EINVAL) 5209 rsp_result = L2CAP_MR_BAD_ID; 5210 else 5211 rsp_result = L2CAP_MR_NOT_ALLOWED; 5212 5213 l2cap_send_move_chan_rsp(chan, rsp_result); 5214 } 5215 5216 chan->move_role = L2CAP_MOVE_ROLE_NONE; 5217 chan->move_state = L2CAP_MOVE_STABLE; 5218 5219 /* Restart data transmission */ 5220 l2cap_ertm_send(chan); 5221 } 5222 5223 /* Invoke with locked chan */ 5224 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result) 5225 { 5226 u8 local_amp_id = chan->local_amp_id; 5227 u8 remote_amp_id = chan->remote_amp_id; 5228 5229 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d", 5230 chan, result, local_amp_id, remote_amp_id); 5231 5232 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) 5233 return; 5234 5235 if (chan->state != BT_CONNECTED) { 5236 l2cap_do_create(chan, result, local_amp_id, remote_amp_id); 5237 } else if (result != L2CAP_MR_SUCCESS) { 5238 l2cap_do_move_cancel(chan, result); 5239 } else { 5240 switch (chan->move_role) { 5241 case L2CAP_MOVE_ROLE_INITIATOR: 5242 l2cap_do_move_initiate(chan, local_amp_id, 5243 remote_amp_id); 5244 break; 5245 case L2CAP_MOVE_ROLE_RESPONDER: 5246 l2cap_do_move_respond(chan, result); 5247 break; 5248 default: 5249 l2cap_do_move_cancel(chan, result); 5250 break; 5251 } 5252 } 5253 } 5254 5255 static inline int l2cap_move_channel_req(struct l2cap_conn *conn, 5256 struct l2cap_cmd_hdr *cmd, 5257 u16 cmd_len, void *data) 5258 { 5259 struct l2cap_move_chan_req *req = data; 5260 struct l2cap_move_chan_rsp rsp; 5261 struct l2cap_chan *chan; 5262 u16 icid = 0; 5263 u16 result = L2CAP_MR_NOT_ALLOWED; 5264 5265 if (cmd_len != sizeof(*req)) 5266 return -EPROTO; 5267 5268 icid = le16_to_cpu(req->icid); 5269 5270 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id); 5271 5272 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP)) 5273 return -EINVAL; 5274 5275 chan = l2cap_get_chan_by_dcid(conn, icid); 5276 if (!chan) { 5277 rsp.icid = cpu_to_le16(icid); 5278 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED); 5279 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP, 5280 sizeof(rsp), &rsp); 5281 return 0; 5282 } 5283 5284 chan->ident = cmd->ident; 5285 5286 if (chan->scid < L2CAP_CID_DYN_START || 5287 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY || 5288 (chan->mode != L2CAP_MODE_ERTM && 5289 chan->mode != L2CAP_MODE_STREAMING)) { 5290 result = L2CAP_MR_NOT_ALLOWED; 5291 goto send_move_response; 5292 } 5293 5294 if (chan->local_amp_id == req->dest_amp_id) { 5295 result = L2CAP_MR_SAME_ID; 5296 goto send_move_response; 5297 } 5298 5299 if (req->dest_amp_id != AMP_ID_BREDR) { 5300 struct hci_dev *hdev; 5301 hdev = hci_dev_get(req->dest_amp_id); 5302 if (!hdev || hdev->dev_type != HCI_AMP || 5303 !test_bit(HCI_UP, &hdev->flags)) { 5304 if (hdev) 5305 hci_dev_put(hdev); 5306 5307 result = L2CAP_MR_BAD_ID; 5308 goto send_move_response; 5309 } 5310 hci_dev_put(hdev); 5311 } 5312 5313 /* Detect a move collision. Only send a collision response 5314 * if this side has "lost", otherwise proceed with the move. 5315 * The winner has the larger bd_addr. 5316 */ 5317 if ((__chan_is_moving(chan) || 5318 chan->move_role != L2CAP_MOVE_ROLE_NONE) && 5319 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) { 5320 result = L2CAP_MR_COLLISION; 5321 goto send_move_response; 5322 } 5323 5324 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER; 5325 l2cap_move_setup(chan); 5326 chan->move_id = req->dest_amp_id; 5327 5328 if (req->dest_amp_id == AMP_ID_BREDR) { 5329 /* Moving to BR/EDR */ 5330 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 5331 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY; 5332 result = L2CAP_MR_PEND; 5333 } else { 5334 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM; 5335 result = L2CAP_MR_SUCCESS; 5336 } 5337 } else { 5338 chan->move_state = L2CAP_MOVE_WAIT_PREPARE; 5339 /* Placeholder - uncomment when amp functions are available */ 5340 /*amp_accept_physical(chan, req->dest_amp_id);*/ 5341 result = L2CAP_MR_PEND; 5342 } 5343 5344 send_move_response: 5345 l2cap_send_move_chan_rsp(chan, result); 5346 5347 l2cap_chan_unlock(chan); 5348 l2cap_chan_put(chan); 5349 5350 return 0; 5351 } 5352 5353 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result) 5354 { 5355 struct l2cap_chan *chan; 5356 struct hci_chan *hchan = NULL; 5357 5358 chan = l2cap_get_chan_by_scid(conn, icid); 5359 if (!chan) { 5360 l2cap_send_move_chan_cfm_icid(conn, icid); 5361 return; 5362 } 5363 5364 __clear_chan_timer(chan); 5365 if (result == L2CAP_MR_PEND) 5366 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT); 5367 5368 switch (chan->move_state) { 5369 case L2CAP_MOVE_WAIT_LOGICAL_COMP: 5370 /* Move confirm will be sent when logical link 5371 * is complete. 5372 */ 5373 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM; 5374 break; 5375 case L2CAP_MOVE_WAIT_RSP_SUCCESS: 5376 if (result == L2CAP_MR_PEND) { 5377 break; 5378 } else if (test_bit(CONN_LOCAL_BUSY, 5379 &chan->conn_state)) { 5380 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY; 5381 } else { 5382 /* Logical link is up or moving to BR/EDR, 5383 * proceed with move 5384 */ 5385 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP; 5386 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED); 5387 } 5388 break; 5389 case L2CAP_MOVE_WAIT_RSP: 5390 /* Moving to AMP */ 5391 if (result == L2CAP_MR_SUCCESS) { 5392 /* Remote is ready, send confirm immediately 5393 * after logical link is ready 5394 */ 5395 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM; 5396 } else { 5397 /* Both logical link and move success 5398 * are required to confirm 5399 */ 5400 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP; 5401 } 5402 5403 /* Placeholder - get hci_chan for logical link */ 5404 if (!hchan) { 5405 /* Logical link not available */ 5406 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5407 break; 5408 } 5409 5410 /* If the logical link is not yet connected, do not 5411 * send confirmation. 5412 */ 5413 if (hchan->state != BT_CONNECTED) 5414 break; 5415 5416 /* Logical link is already ready to go */ 5417 5418 chan->hs_hcon = hchan->conn; 5419 chan->hs_hcon->l2cap_data = chan->conn; 5420 5421 if (result == L2CAP_MR_SUCCESS) { 5422 /* Can confirm now */ 5423 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED); 5424 } else { 5425 /* Now only need move success 5426 * to confirm 5427 */ 5428 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS; 5429 } 5430 5431 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS); 5432 break; 5433 default: 5434 /* Any other amp move state means the move failed. */ 5435 chan->move_id = chan->local_amp_id; 5436 l2cap_move_done(chan); 5437 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5438 } 5439 5440 l2cap_chan_unlock(chan); 5441 l2cap_chan_put(chan); 5442 } 5443 5444 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid, 5445 u16 result) 5446 { 5447 struct l2cap_chan *chan; 5448 5449 chan = l2cap_get_chan_by_ident(conn, ident); 5450 if (!chan) { 5451 /* Could not locate channel, icid is best guess */ 5452 l2cap_send_move_chan_cfm_icid(conn, icid); 5453 return; 5454 } 5455 5456 __clear_chan_timer(chan); 5457 5458 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) { 5459 if (result == L2CAP_MR_COLLISION) { 5460 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER; 5461 } else { 5462 /* Cleanup - cancel move */ 5463 chan->move_id = chan->local_amp_id; 5464 l2cap_move_done(chan); 5465 } 5466 } 5467 5468 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); 5469 5470 l2cap_chan_unlock(chan); 5471 l2cap_chan_put(chan); 5472 } 5473 5474 static int l2cap_move_channel_rsp(struct l2cap_conn *conn, 5475 struct l2cap_cmd_hdr *cmd, 5476 u16 cmd_len, void *data) 5477 { 5478 struct l2cap_move_chan_rsp *rsp = data; 5479 u16 icid, result; 5480 5481 if (cmd_len != sizeof(*rsp)) 5482 return -EPROTO; 5483 5484 icid = le16_to_cpu(rsp->icid); 5485 result = le16_to_cpu(rsp->result); 5486 5487 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result); 5488 5489 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND) 5490 l2cap_move_continue(conn, icid, result); 5491 else 5492 l2cap_move_fail(conn, cmd->ident, icid, result); 5493 5494 return 0; 5495 } 5496 5497 static int l2cap_move_channel_confirm(struct l2cap_conn *conn, 5498 struct l2cap_cmd_hdr *cmd, 5499 u16 cmd_len, void *data) 5500 { 5501 struct l2cap_move_chan_cfm *cfm = data; 5502 struct l2cap_chan *chan; 5503 u16 icid, result; 5504 5505 if (cmd_len != sizeof(*cfm)) 5506 return -EPROTO; 5507 5508 icid = le16_to_cpu(cfm->icid); 5509 result = le16_to_cpu(cfm->result); 5510 5511 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result); 5512 5513 chan = l2cap_get_chan_by_dcid(conn, icid); 5514 if (!chan) { 5515 /* Spec requires a response even if the icid was not found */ 5516 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid); 5517 return 0; 5518 } 5519 5520 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) { 5521 if (result == L2CAP_MC_CONFIRMED) { 5522 chan->local_amp_id = chan->move_id; 5523 if (chan->local_amp_id == AMP_ID_BREDR) 5524 __release_logical_link(chan); 5525 } else { 5526 chan->move_id = chan->local_amp_id; 5527 } 5528 5529 l2cap_move_done(chan); 5530 } 5531 5532 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid); 5533 5534 l2cap_chan_unlock(chan); 5535 l2cap_chan_put(chan); 5536 5537 return 0; 5538 } 5539 5540 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn, 5541 struct l2cap_cmd_hdr *cmd, 5542 u16 cmd_len, void *data) 5543 { 5544 struct l2cap_move_chan_cfm_rsp *rsp = data; 5545 struct l2cap_chan *chan; 5546 u16 icid; 5547 5548 if (cmd_len != sizeof(*rsp)) 5549 return -EPROTO; 5550 5551 icid = le16_to_cpu(rsp->icid); 5552 5553 BT_DBG("icid 0x%4.4x", icid); 5554 5555 chan = l2cap_get_chan_by_scid(conn, icid); 5556 if (!chan) 5557 return 0; 5558 5559 __clear_chan_timer(chan); 5560 5561 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) { 5562 chan->local_amp_id = chan->move_id; 5563 5564 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan) 5565 __release_logical_link(chan); 5566 5567 l2cap_move_done(chan); 5568 } 5569 5570 l2cap_chan_unlock(chan); 5571 l2cap_chan_put(chan); 5572 5573 return 0; 5574 } 5575 5576 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn, 5577 struct l2cap_cmd_hdr *cmd, 5578 u16 cmd_len, u8 *data) 5579 { 5580 struct hci_conn *hcon = conn->hcon; 5581 struct l2cap_conn_param_update_req *req; 5582 struct l2cap_conn_param_update_rsp rsp; 5583 u16 min, max, latency, to_multiplier; 5584 int err; 5585 5586 if (hcon->role != HCI_ROLE_MASTER) 5587 return -EINVAL; 5588 5589 if (cmd_len != sizeof(struct l2cap_conn_param_update_req)) 5590 return -EPROTO; 5591 5592 req = (struct l2cap_conn_param_update_req *) data; 5593 min = __le16_to_cpu(req->min); 5594 max = __le16_to_cpu(req->max); 5595 latency = __le16_to_cpu(req->latency); 5596 to_multiplier = __le16_to_cpu(req->to_multiplier); 5597 5598 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x", 5599 min, max, latency, to_multiplier); 5600 5601 memset(&rsp, 0, sizeof(rsp)); 5602 5603 err = hci_check_conn_params(min, max, latency, to_multiplier); 5604 if (err) 5605 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED); 5606 else 5607 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED); 5608 5609 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP, 5610 sizeof(rsp), &rsp); 5611 5612 if (!err) { 5613 u8 store_hint; 5614 5615 store_hint = hci_le_conn_update(hcon, min, max, latency, 5616 to_multiplier); 5617 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type, 5618 store_hint, min, max, latency, 5619 to_multiplier); 5620 5621 } 5622 5623 return 0; 5624 } 5625 5626 static int l2cap_le_connect_rsp(struct l2cap_conn *conn, 5627 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5628 u8 *data) 5629 { 5630 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data; 5631 struct hci_conn *hcon = conn->hcon; 5632 u16 dcid, mtu, mps, credits, result; 5633 struct l2cap_chan *chan; 5634 int err, sec_level; 5635 5636 if (cmd_len < sizeof(*rsp)) 5637 return -EPROTO; 5638 5639 dcid = __le16_to_cpu(rsp->dcid); 5640 mtu = __le16_to_cpu(rsp->mtu); 5641 mps = __le16_to_cpu(rsp->mps); 5642 credits = __le16_to_cpu(rsp->credits); 5643 result = __le16_to_cpu(rsp->result); 5644 5645 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 || 5646 dcid < L2CAP_CID_DYN_START || 5647 dcid > L2CAP_CID_LE_DYN_END)) 5648 return -EPROTO; 5649 5650 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x", 5651 dcid, mtu, mps, credits, result); 5652 5653 mutex_lock(&conn->chan_lock); 5654 5655 chan = __l2cap_get_chan_by_ident(conn, cmd->ident); 5656 if (!chan) { 5657 err = -EBADSLT; 5658 goto unlock; 5659 } 5660 5661 err = 0; 5662 5663 l2cap_chan_lock(chan); 5664 5665 switch (result) { 5666 case L2CAP_CR_LE_SUCCESS: 5667 if (__l2cap_get_chan_by_dcid(conn, dcid)) { 5668 err = -EBADSLT; 5669 break; 5670 } 5671 5672 chan->ident = 0; 5673 chan->dcid = dcid; 5674 chan->omtu = mtu; 5675 chan->remote_mps = mps; 5676 chan->tx_credits = credits; 5677 l2cap_chan_ready(chan); 5678 break; 5679 5680 case L2CAP_CR_LE_AUTHENTICATION: 5681 case L2CAP_CR_LE_ENCRYPTION: 5682 /* If we already have MITM protection we can't do 5683 * anything. 5684 */ 5685 if (hcon->sec_level > BT_SECURITY_MEDIUM) { 5686 l2cap_chan_del(chan, ECONNREFUSED); 5687 break; 5688 } 5689 5690 sec_level = hcon->sec_level + 1; 5691 if (chan->sec_level < sec_level) 5692 chan->sec_level = sec_level; 5693 5694 /* We'll need to send a new Connect Request */ 5695 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags); 5696 5697 smp_conn_security(hcon, chan->sec_level); 5698 break; 5699 5700 default: 5701 l2cap_chan_del(chan, ECONNREFUSED); 5702 break; 5703 } 5704 5705 l2cap_chan_unlock(chan); 5706 5707 unlock: 5708 mutex_unlock(&conn->chan_lock); 5709 5710 return err; 5711 } 5712 5713 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn, 5714 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5715 u8 *data) 5716 { 5717 int err = 0; 5718 5719 switch (cmd->code) { 5720 case L2CAP_COMMAND_REJ: 5721 l2cap_command_rej(conn, cmd, cmd_len, data); 5722 break; 5723 5724 case L2CAP_CONN_REQ: 5725 err = l2cap_connect_req(conn, cmd, cmd_len, data); 5726 break; 5727 5728 case L2CAP_CONN_RSP: 5729 case L2CAP_CREATE_CHAN_RSP: 5730 l2cap_connect_create_rsp(conn, cmd, cmd_len, data); 5731 break; 5732 5733 case L2CAP_CONF_REQ: 5734 err = l2cap_config_req(conn, cmd, cmd_len, data); 5735 break; 5736 5737 case L2CAP_CONF_RSP: 5738 l2cap_config_rsp(conn, cmd, cmd_len, data); 5739 break; 5740 5741 case L2CAP_DISCONN_REQ: 5742 err = l2cap_disconnect_req(conn, cmd, cmd_len, data); 5743 break; 5744 5745 case L2CAP_DISCONN_RSP: 5746 l2cap_disconnect_rsp(conn, cmd, cmd_len, data); 5747 break; 5748 5749 case L2CAP_ECHO_REQ: 5750 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data); 5751 break; 5752 5753 case L2CAP_ECHO_RSP: 5754 break; 5755 5756 case L2CAP_INFO_REQ: 5757 err = l2cap_information_req(conn, cmd, cmd_len, data); 5758 break; 5759 5760 case L2CAP_INFO_RSP: 5761 l2cap_information_rsp(conn, cmd, cmd_len, data); 5762 break; 5763 5764 case L2CAP_CREATE_CHAN_REQ: 5765 err = l2cap_create_channel_req(conn, cmd, cmd_len, data); 5766 break; 5767 5768 case L2CAP_MOVE_CHAN_REQ: 5769 err = l2cap_move_channel_req(conn, cmd, cmd_len, data); 5770 break; 5771 5772 case L2CAP_MOVE_CHAN_RSP: 5773 l2cap_move_channel_rsp(conn, cmd, cmd_len, data); 5774 break; 5775 5776 case L2CAP_MOVE_CHAN_CFM: 5777 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data); 5778 break; 5779 5780 case L2CAP_MOVE_CHAN_CFM_RSP: 5781 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data); 5782 break; 5783 5784 default: 5785 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code); 5786 err = -EINVAL; 5787 break; 5788 } 5789 5790 return err; 5791 } 5792 5793 static int l2cap_le_connect_req(struct l2cap_conn *conn, 5794 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5795 u8 *data) 5796 { 5797 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data; 5798 struct l2cap_le_conn_rsp rsp; 5799 struct l2cap_chan *chan, *pchan; 5800 u16 dcid, scid, credits, mtu, mps; 5801 __le16 psm; 5802 u8 result; 5803 5804 if (cmd_len != sizeof(*req)) 5805 return -EPROTO; 5806 5807 scid = __le16_to_cpu(req->scid); 5808 mtu = __le16_to_cpu(req->mtu); 5809 mps = __le16_to_cpu(req->mps); 5810 psm = req->psm; 5811 dcid = 0; 5812 credits = 0; 5813 5814 if (mtu < 23 || mps < 23) 5815 return -EPROTO; 5816 5817 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm), 5818 scid, mtu, mps); 5819 5820 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A 5821 * page 1059: 5822 * 5823 * Valid range: 0x0001-0x00ff 5824 * 5825 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges 5826 */ 5827 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) { 5828 result = L2CAP_CR_LE_BAD_PSM; 5829 chan = NULL; 5830 goto response; 5831 } 5832 5833 /* Check if we have socket listening on psm */ 5834 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src, 5835 &conn->hcon->dst, LE_LINK); 5836 if (!pchan) { 5837 result = L2CAP_CR_LE_BAD_PSM; 5838 chan = NULL; 5839 goto response; 5840 } 5841 5842 mutex_lock(&conn->chan_lock); 5843 l2cap_chan_lock(pchan); 5844 5845 if (!smp_sufficient_security(conn->hcon, pchan->sec_level, 5846 SMP_ALLOW_STK)) { 5847 result = L2CAP_CR_LE_AUTHENTICATION; 5848 chan = NULL; 5849 goto response_unlock; 5850 } 5851 5852 /* Check for valid dynamic CID range */ 5853 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) { 5854 result = L2CAP_CR_LE_INVALID_SCID; 5855 chan = NULL; 5856 goto response_unlock; 5857 } 5858 5859 /* Check if we already have channel with that dcid */ 5860 if (__l2cap_get_chan_by_dcid(conn, scid)) { 5861 result = L2CAP_CR_LE_SCID_IN_USE; 5862 chan = NULL; 5863 goto response_unlock; 5864 } 5865 5866 chan = pchan->ops->new_connection(pchan); 5867 if (!chan) { 5868 result = L2CAP_CR_LE_NO_MEM; 5869 goto response_unlock; 5870 } 5871 5872 bacpy(&chan->src, &conn->hcon->src); 5873 bacpy(&chan->dst, &conn->hcon->dst); 5874 chan->src_type = bdaddr_src_type(conn->hcon); 5875 chan->dst_type = bdaddr_dst_type(conn->hcon); 5876 chan->psm = psm; 5877 chan->dcid = scid; 5878 chan->omtu = mtu; 5879 chan->remote_mps = mps; 5880 5881 __l2cap_chan_add(conn, chan); 5882 5883 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits)); 5884 5885 dcid = chan->scid; 5886 credits = chan->rx_credits; 5887 5888 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 5889 5890 chan->ident = cmd->ident; 5891 5892 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 5893 l2cap_state_change(chan, BT_CONNECT2); 5894 /* The following result value is actually not defined 5895 * for LE CoC but we use it to let the function know 5896 * that it should bail out after doing its cleanup 5897 * instead of sending a response. 5898 */ 5899 result = L2CAP_CR_PEND; 5900 chan->ops->defer(chan); 5901 } else { 5902 l2cap_chan_ready(chan); 5903 result = L2CAP_CR_LE_SUCCESS; 5904 } 5905 5906 response_unlock: 5907 l2cap_chan_unlock(pchan); 5908 mutex_unlock(&conn->chan_lock); 5909 l2cap_chan_put(pchan); 5910 5911 if (result == L2CAP_CR_PEND) 5912 return 0; 5913 5914 response: 5915 if (chan) { 5916 rsp.mtu = cpu_to_le16(chan->imtu); 5917 rsp.mps = cpu_to_le16(chan->mps); 5918 } else { 5919 rsp.mtu = 0; 5920 rsp.mps = 0; 5921 } 5922 5923 rsp.dcid = cpu_to_le16(dcid); 5924 rsp.credits = cpu_to_le16(credits); 5925 rsp.result = cpu_to_le16(result); 5926 5927 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp); 5928 5929 return 0; 5930 } 5931 5932 static inline int l2cap_le_credits(struct l2cap_conn *conn, 5933 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5934 u8 *data) 5935 { 5936 struct l2cap_le_credits *pkt; 5937 struct l2cap_chan *chan; 5938 u16 cid, credits, max_credits; 5939 5940 if (cmd_len != sizeof(*pkt)) 5941 return -EPROTO; 5942 5943 pkt = (struct l2cap_le_credits *) data; 5944 cid = __le16_to_cpu(pkt->cid); 5945 credits = __le16_to_cpu(pkt->credits); 5946 5947 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits); 5948 5949 chan = l2cap_get_chan_by_dcid(conn, cid); 5950 if (!chan) 5951 return -EBADSLT; 5952 5953 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits; 5954 if (credits > max_credits) { 5955 BT_ERR("LE credits overflow"); 5956 l2cap_send_disconn_req(chan, ECONNRESET); 5957 5958 /* Return 0 so that we don't trigger an unnecessary 5959 * command reject packet. 5960 */ 5961 goto unlock; 5962 } 5963 5964 chan->tx_credits += credits; 5965 5966 /* Resume sending */ 5967 l2cap_le_flowctl_send(chan); 5968 5969 if (chan->tx_credits) 5970 chan->ops->resume(chan); 5971 5972 unlock: 5973 l2cap_chan_unlock(chan); 5974 l2cap_chan_put(chan); 5975 5976 return 0; 5977 } 5978 5979 static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, 5980 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 5981 u8 *data) 5982 { 5983 struct l2cap_ecred_conn_req *req = (void *) data; 5984 struct { 5985 struct l2cap_ecred_conn_rsp rsp; 5986 __le16 dcid[L2CAP_ECRED_MAX_CID]; 5987 } __packed pdu; 5988 struct l2cap_chan *chan, *pchan; 5989 u16 mtu, mps; 5990 __le16 psm; 5991 u8 result, len = 0; 5992 int i, num_scid; 5993 bool defer = false; 5994 5995 if (!enable_ecred) 5996 return -EINVAL; 5997 5998 if (cmd_len < sizeof(*req) || (cmd_len - sizeof(*req)) % sizeof(u16)) { 5999 result = L2CAP_CR_LE_INVALID_PARAMS; 6000 goto response; 6001 } 6002 6003 cmd_len -= sizeof(*req); 6004 num_scid = cmd_len / sizeof(u16); 6005 6006 if (num_scid > ARRAY_SIZE(pdu.dcid)) { 6007 result = L2CAP_CR_LE_INVALID_PARAMS; 6008 goto response; 6009 } 6010 6011 mtu = __le16_to_cpu(req->mtu); 6012 mps = __le16_to_cpu(req->mps); 6013 6014 if (mtu < L2CAP_ECRED_MIN_MTU || mps < L2CAP_ECRED_MIN_MPS) { 6015 result = L2CAP_CR_LE_UNACCEPT_PARAMS; 6016 goto response; 6017 } 6018 6019 psm = req->psm; 6020 6021 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A 6022 * page 1059: 6023 * 6024 * Valid range: 0x0001-0x00ff 6025 * 6026 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges 6027 */ 6028 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) { 6029 result = L2CAP_CR_LE_BAD_PSM; 6030 goto response; 6031 } 6032 6033 BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps); 6034 6035 memset(&pdu, 0, sizeof(pdu)); 6036 6037 /* Check if we have socket listening on psm */ 6038 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src, 6039 &conn->hcon->dst, LE_LINK); 6040 if (!pchan) { 6041 result = L2CAP_CR_LE_BAD_PSM; 6042 goto response; 6043 } 6044 6045 mutex_lock(&conn->chan_lock); 6046 l2cap_chan_lock(pchan); 6047 6048 if (!smp_sufficient_security(conn->hcon, pchan->sec_level, 6049 SMP_ALLOW_STK)) { 6050 result = L2CAP_CR_LE_AUTHENTICATION; 6051 goto unlock; 6052 } 6053 6054 result = L2CAP_CR_LE_SUCCESS; 6055 6056 for (i = 0; i < num_scid; i++) { 6057 u16 scid = __le16_to_cpu(req->scid[i]); 6058 6059 BT_DBG("scid[%d] 0x%4.4x", i, scid); 6060 6061 pdu.dcid[i] = 0x0000; 6062 len += sizeof(*pdu.dcid); 6063 6064 /* Check for valid dynamic CID range */ 6065 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) { 6066 result = L2CAP_CR_LE_INVALID_SCID; 6067 continue; 6068 } 6069 6070 /* Check if we already have channel with that dcid */ 6071 if (__l2cap_get_chan_by_dcid(conn, scid)) { 6072 result = L2CAP_CR_LE_SCID_IN_USE; 6073 continue; 6074 } 6075 6076 chan = pchan->ops->new_connection(pchan); 6077 if (!chan) { 6078 result = L2CAP_CR_LE_NO_MEM; 6079 continue; 6080 } 6081 6082 bacpy(&chan->src, &conn->hcon->src); 6083 bacpy(&chan->dst, &conn->hcon->dst); 6084 chan->src_type = bdaddr_src_type(conn->hcon); 6085 chan->dst_type = bdaddr_dst_type(conn->hcon); 6086 chan->psm = psm; 6087 chan->dcid = scid; 6088 chan->omtu = mtu; 6089 chan->remote_mps = mps; 6090 6091 __l2cap_chan_add(conn, chan); 6092 6093 l2cap_ecred_init(chan, __le16_to_cpu(req->credits)); 6094 6095 /* Init response */ 6096 if (!pdu.rsp.credits) { 6097 pdu.rsp.mtu = cpu_to_le16(chan->imtu); 6098 pdu.rsp.mps = cpu_to_le16(chan->mps); 6099 pdu.rsp.credits = cpu_to_le16(chan->rx_credits); 6100 } 6101 6102 pdu.dcid[i] = cpu_to_le16(chan->scid); 6103 6104 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 6105 6106 chan->ident = cmd->ident; 6107 chan->mode = L2CAP_MODE_EXT_FLOWCTL; 6108 6109 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 6110 l2cap_state_change(chan, BT_CONNECT2); 6111 defer = true; 6112 chan->ops->defer(chan); 6113 } else { 6114 l2cap_chan_ready(chan); 6115 } 6116 } 6117 6118 unlock: 6119 l2cap_chan_unlock(pchan); 6120 mutex_unlock(&conn->chan_lock); 6121 l2cap_chan_put(pchan); 6122 6123 response: 6124 pdu.rsp.result = cpu_to_le16(result); 6125 6126 if (defer) 6127 return 0; 6128 6129 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_CONN_RSP, 6130 sizeof(pdu.rsp) + len, &pdu); 6131 6132 return 0; 6133 } 6134 6135 static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn, 6136 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6137 u8 *data) 6138 { 6139 struct l2cap_ecred_conn_rsp *rsp = (void *) data; 6140 struct hci_conn *hcon = conn->hcon; 6141 u16 mtu, mps, credits, result; 6142 struct l2cap_chan *chan, *tmp; 6143 int err = 0, sec_level; 6144 int i = 0; 6145 6146 if (cmd_len < sizeof(*rsp)) 6147 return -EPROTO; 6148 6149 mtu = __le16_to_cpu(rsp->mtu); 6150 mps = __le16_to_cpu(rsp->mps); 6151 credits = __le16_to_cpu(rsp->credits); 6152 result = __le16_to_cpu(rsp->result); 6153 6154 BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits, 6155 result); 6156 6157 mutex_lock(&conn->chan_lock); 6158 6159 cmd_len -= sizeof(*rsp); 6160 6161 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { 6162 u16 dcid; 6163 6164 if (chan->ident != cmd->ident || 6165 chan->mode != L2CAP_MODE_EXT_FLOWCTL || 6166 chan->state == BT_CONNECTED) 6167 continue; 6168 6169 l2cap_chan_lock(chan); 6170 6171 /* Check that there is a dcid for each pending channel */ 6172 if (cmd_len < sizeof(dcid)) { 6173 l2cap_chan_del(chan, ECONNREFUSED); 6174 l2cap_chan_unlock(chan); 6175 continue; 6176 } 6177 6178 dcid = __le16_to_cpu(rsp->dcid[i++]); 6179 cmd_len -= sizeof(u16); 6180 6181 BT_DBG("dcid[%d] 0x%4.4x", i, dcid); 6182 6183 /* Check if dcid is already in use */ 6184 if (dcid && __l2cap_get_chan_by_dcid(conn, dcid)) { 6185 /* If a device receives a 6186 * L2CAP_CREDIT_BASED_CONNECTION_RSP packet with an 6187 * already-assigned Destination CID, then both the 6188 * original channel and the new channel shall be 6189 * immediately discarded and not used. 6190 */ 6191 l2cap_chan_del(chan, ECONNREFUSED); 6192 l2cap_chan_unlock(chan); 6193 chan = __l2cap_get_chan_by_dcid(conn, dcid); 6194 l2cap_chan_lock(chan); 6195 l2cap_chan_del(chan, ECONNRESET); 6196 l2cap_chan_unlock(chan); 6197 continue; 6198 } 6199 6200 switch (result) { 6201 case L2CAP_CR_LE_AUTHENTICATION: 6202 case L2CAP_CR_LE_ENCRYPTION: 6203 /* If we already have MITM protection we can't do 6204 * anything. 6205 */ 6206 if (hcon->sec_level > BT_SECURITY_MEDIUM) { 6207 l2cap_chan_del(chan, ECONNREFUSED); 6208 break; 6209 } 6210 6211 sec_level = hcon->sec_level + 1; 6212 if (chan->sec_level < sec_level) 6213 chan->sec_level = sec_level; 6214 6215 /* We'll need to send a new Connect Request */ 6216 clear_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags); 6217 6218 smp_conn_security(hcon, chan->sec_level); 6219 break; 6220 6221 case L2CAP_CR_LE_BAD_PSM: 6222 l2cap_chan_del(chan, ECONNREFUSED); 6223 break; 6224 6225 default: 6226 /* If dcid was not set it means channels was refused */ 6227 if (!dcid) { 6228 l2cap_chan_del(chan, ECONNREFUSED); 6229 break; 6230 } 6231 6232 chan->ident = 0; 6233 chan->dcid = dcid; 6234 chan->omtu = mtu; 6235 chan->remote_mps = mps; 6236 chan->tx_credits = credits; 6237 l2cap_chan_ready(chan); 6238 break; 6239 } 6240 6241 l2cap_chan_unlock(chan); 6242 } 6243 6244 mutex_unlock(&conn->chan_lock); 6245 6246 return err; 6247 } 6248 6249 static inline int l2cap_ecred_reconf_req(struct l2cap_conn *conn, 6250 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6251 u8 *data) 6252 { 6253 struct l2cap_ecred_reconf_req *req = (void *) data; 6254 struct l2cap_ecred_reconf_rsp rsp; 6255 u16 mtu, mps, result; 6256 struct l2cap_chan *chan; 6257 int i, num_scid; 6258 6259 if (!enable_ecred) 6260 return -EINVAL; 6261 6262 if (cmd_len < sizeof(*req) || cmd_len - sizeof(*req) % sizeof(u16)) { 6263 result = L2CAP_CR_LE_INVALID_PARAMS; 6264 goto respond; 6265 } 6266 6267 mtu = __le16_to_cpu(req->mtu); 6268 mps = __le16_to_cpu(req->mps); 6269 6270 BT_DBG("mtu %u mps %u", mtu, mps); 6271 6272 if (mtu < L2CAP_ECRED_MIN_MTU) { 6273 result = L2CAP_RECONF_INVALID_MTU; 6274 goto respond; 6275 } 6276 6277 if (mps < L2CAP_ECRED_MIN_MPS) { 6278 result = L2CAP_RECONF_INVALID_MPS; 6279 goto respond; 6280 } 6281 6282 cmd_len -= sizeof(*req); 6283 num_scid = cmd_len / sizeof(u16); 6284 result = L2CAP_RECONF_SUCCESS; 6285 6286 for (i = 0; i < num_scid; i++) { 6287 u16 scid; 6288 6289 scid = __le16_to_cpu(req->scid[i]); 6290 if (!scid) 6291 return -EPROTO; 6292 6293 chan = __l2cap_get_chan_by_dcid(conn, scid); 6294 if (!chan) 6295 continue; 6296 6297 /* If the MTU value is decreased for any of the included 6298 * channels, then the receiver shall disconnect all 6299 * included channels. 6300 */ 6301 if (chan->omtu > mtu) { 6302 BT_ERR("chan %p decreased MTU %u -> %u", chan, 6303 chan->omtu, mtu); 6304 result = L2CAP_RECONF_INVALID_MTU; 6305 } 6306 6307 chan->omtu = mtu; 6308 chan->remote_mps = mps; 6309 } 6310 6311 respond: 6312 rsp.result = cpu_to_le16(result); 6313 6314 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_RECONF_RSP, sizeof(rsp), 6315 &rsp); 6316 6317 return 0; 6318 } 6319 6320 static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn, 6321 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6322 u8 *data) 6323 { 6324 struct l2cap_chan *chan, *tmp; 6325 struct l2cap_ecred_conn_rsp *rsp = (void *) data; 6326 u16 result; 6327 6328 if (cmd_len < sizeof(*rsp)) 6329 return -EPROTO; 6330 6331 result = __le16_to_cpu(rsp->result); 6332 6333 BT_DBG("result 0x%4.4x", rsp->result); 6334 6335 if (!result) 6336 return 0; 6337 6338 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { 6339 if (chan->ident != cmd->ident) 6340 continue; 6341 6342 l2cap_chan_del(chan, ECONNRESET); 6343 } 6344 6345 return 0; 6346 } 6347 6348 static inline int l2cap_le_command_rej(struct l2cap_conn *conn, 6349 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6350 u8 *data) 6351 { 6352 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data; 6353 struct l2cap_chan *chan; 6354 6355 if (cmd_len < sizeof(*rej)) 6356 return -EPROTO; 6357 6358 mutex_lock(&conn->chan_lock); 6359 6360 chan = __l2cap_get_chan_by_ident(conn, cmd->ident); 6361 if (!chan) 6362 goto done; 6363 6364 l2cap_chan_lock(chan); 6365 l2cap_chan_del(chan, ECONNREFUSED); 6366 l2cap_chan_unlock(chan); 6367 6368 done: 6369 mutex_unlock(&conn->chan_lock); 6370 return 0; 6371 } 6372 6373 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn, 6374 struct l2cap_cmd_hdr *cmd, u16 cmd_len, 6375 u8 *data) 6376 { 6377 int err = 0; 6378 6379 switch (cmd->code) { 6380 case L2CAP_COMMAND_REJ: 6381 l2cap_le_command_rej(conn, cmd, cmd_len, data); 6382 break; 6383 6384 case L2CAP_CONN_PARAM_UPDATE_REQ: 6385 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data); 6386 break; 6387 6388 case L2CAP_CONN_PARAM_UPDATE_RSP: 6389 break; 6390 6391 case L2CAP_LE_CONN_RSP: 6392 l2cap_le_connect_rsp(conn, cmd, cmd_len, data); 6393 break; 6394 6395 case L2CAP_LE_CONN_REQ: 6396 err = l2cap_le_connect_req(conn, cmd, cmd_len, data); 6397 break; 6398 6399 case L2CAP_LE_CREDITS: 6400 err = l2cap_le_credits(conn, cmd, cmd_len, data); 6401 break; 6402 6403 case L2CAP_ECRED_CONN_REQ: 6404 err = l2cap_ecred_conn_req(conn, cmd, cmd_len, data); 6405 break; 6406 6407 case L2CAP_ECRED_CONN_RSP: 6408 err = l2cap_ecred_conn_rsp(conn, cmd, cmd_len, data); 6409 break; 6410 6411 case L2CAP_ECRED_RECONF_REQ: 6412 err = l2cap_ecred_reconf_req(conn, cmd, cmd_len, data); 6413 break; 6414 6415 case L2CAP_ECRED_RECONF_RSP: 6416 err = l2cap_ecred_reconf_rsp(conn, cmd, cmd_len, data); 6417 break; 6418 6419 case L2CAP_DISCONN_REQ: 6420 err = l2cap_disconnect_req(conn, cmd, cmd_len, data); 6421 break; 6422 6423 case L2CAP_DISCONN_RSP: 6424 l2cap_disconnect_rsp(conn, cmd, cmd_len, data); 6425 break; 6426 6427 default: 6428 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code); 6429 err = -EINVAL; 6430 break; 6431 } 6432 6433 return err; 6434 } 6435 6436 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn, 6437 struct sk_buff *skb) 6438 { 6439 struct hci_conn *hcon = conn->hcon; 6440 struct l2cap_cmd_hdr *cmd; 6441 u16 len; 6442 int err; 6443 6444 if (hcon->type != LE_LINK) 6445 goto drop; 6446 6447 if (skb->len < L2CAP_CMD_HDR_SIZE) 6448 goto drop; 6449 6450 cmd = (void *) skb->data; 6451 skb_pull(skb, L2CAP_CMD_HDR_SIZE); 6452 6453 len = le16_to_cpu(cmd->len); 6454 6455 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident); 6456 6457 if (len != skb->len || !cmd->ident) { 6458 BT_DBG("corrupted command"); 6459 goto drop; 6460 } 6461 6462 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data); 6463 if (err) { 6464 struct l2cap_cmd_rej_unk rej; 6465 6466 BT_ERR("Wrong link type (%d)", err); 6467 6468 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD); 6469 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ, 6470 sizeof(rej), &rej); 6471 } 6472 6473 drop: 6474 kfree_skb(skb); 6475 } 6476 6477 static inline void l2cap_sig_channel(struct l2cap_conn *conn, 6478 struct sk_buff *skb) 6479 { 6480 struct hci_conn *hcon = conn->hcon; 6481 struct l2cap_cmd_hdr *cmd; 6482 int err; 6483 6484 l2cap_raw_recv(conn, skb); 6485 6486 if (hcon->type != ACL_LINK) 6487 goto drop; 6488 6489 while (skb->len >= L2CAP_CMD_HDR_SIZE) { 6490 u16 len; 6491 6492 cmd = (void *) skb->data; 6493 skb_pull(skb, L2CAP_CMD_HDR_SIZE); 6494 6495 len = le16_to_cpu(cmd->len); 6496 6497 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, 6498 cmd->ident); 6499 6500 if (len > skb->len || !cmd->ident) { 6501 BT_DBG("corrupted command"); 6502 break; 6503 } 6504 6505 err = l2cap_bredr_sig_cmd(conn, cmd, len, skb->data); 6506 if (err) { 6507 struct l2cap_cmd_rej_unk rej; 6508 6509 BT_ERR("Wrong link type (%d)", err); 6510 6511 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD); 6512 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ, 6513 sizeof(rej), &rej); 6514 } 6515 6516 skb_pull(skb, len); 6517 } 6518 6519 drop: 6520 kfree_skb(skb); 6521 } 6522 6523 static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb) 6524 { 6525 u16 our_fcs, rcv_fcs; 6526 int hdr_size; 6527 6528 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) 6529 hdr_size = L2CAP_EXT_HDR_SIZE; 6530 else 6531 hdr_size = L2CAP_ENH_HDR_SIZE; 6532 6533 if (chan->fcs == L2CAP_FCS_CRC16) { 6534 skb_trim(skb, skb->len - L2CAP_FCS_SIZE); 6535 rcv_fcs = get_unaligned_le16(skb->data + skb->len); 6536 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size); 6537 6538 if (our_fcs != rcv_fcs) 6539 return -EBADMSG; 6540 } 6541 return 0; 6542 } 6543 6544 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan) 6545 { 6546 struct l2cap_ctrl control; 6547 6548 BT_DBG("chan %p", chan); 6549 6550 memset(&control, 0, sizeof(control)); 6551 control.sframe = 1; 6552 control.final = 1; 6553 control.reqseq = chan->buffer_seq; 6554 set_bit(CONN_SEND_FBIT, &chan->conn_state); 6555 6556 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 6557 control.super = L2CAP_SUPER_RNR; 6558 l2cap_send_sframe(chan, &control); 6559 } 6560 6561 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) && 6562 chan->unacked_frames > 0) 6563 __set_retrans_timer(chan); 6564 6565 /* Send pending iframes */ 6566 l2cap_ertm_send(chan); 6567 6568 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) && 6569 test_bit(CONN_SEND_FBIT, &chan->conn_state)) { 6570 /* F-bit wasn't sent in an s-frame or i-frame yet, so 6571 * send it now. 6572 */ 6573 control.super = L2CAP_SUPER_RR; 6574 l2cap_send_sframe(chan, &control); 6575 } 6576 } 6577 6578 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag, 6579 struct sk_buff **last_frag) 6580 { 6581 /* skb->len reflects data in skb as well as all fragments 6582 * skb->data_len reflects only data in fragments 6583 */ 6584 if (!skb_has_frag_list(skb)) 6585 skb_shinfo(skb)->frag_list = new_frag; 6586 6587 new_frag->next = NULL; 6588 6589 (*last_frag)->next = new_frag; 6590 *last_frag = new_frag; 6591 6592 skb->len += new_frag->len; 6593 skb->data_len += new_frag->len; 6594 skb->truesize += new_frag->truesize; 6595 } 6596 6597 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, 6598 struct l2cap_ctrl *control) 6599 { 6600 int err = -EINVAL; 6601 6602 switch (control->sar) { 6603 case L2CAP_SAR_UNSEGMENTED: 6604 if (chan->sdu) 6605 break; 6606 6607 err = chan->ops->recv(chan, skb); 6608 break; 6609 6610 case L2CAP_SAR_START: 6611 if (chan->sdu) 6612 break; 6613 6614 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE)) 6615 break; 6616 6617 chan->sdu_len = get_unaligned_le16(skb->data); 6618 skb_pull(skb, L2CAP_SDULEN_SIZE); 6619 6620 if (chan->sdu_len > chan->imtu) { 6621 err = -EMSGSIZE; 6622 break; 6623 } 6624 6625 if (skb->len >= chan->sdu_len) 6626 break; 6627 6628 chan->sdu = skb; 6629 chan->sdu_last_frag = skb; 6630 6631 skb = NULL; 6632 err = 0; 6633 break; 6634 6635 case L2CAP_SAR_CONTINUE: 6636 if (!chan->sdu) 6637 break; 6638 6639 append_skb_frag(chan->sdu, skb, 6640 &chan->sdu_last_frag); 6641 skb = NULL; 6642 6643 if (chan->sdu->len >= chan->sdu_len) 6644 break; 6645 6646 err = 0; 6647 break; 6648 6649 case L2CAP_SAR_END: 6650 if (!chan->sdu) 6651 break; 6652 6653 append_skb_frag(chan->sdu, skb, 6654 &chan->sdu_last_frag); 6655 skb = NULL; 6656 6657 if (chan->sdu->len != chan->sdu_len) 6658 break; 6659 6660 err = chan->ops->recv(chan, chan->sdu); 6661 6662 if (!err) { 6663 /* Reassembly complete */ 6664 chan->sdu = NULL; 6665 chan->sdu_last_frag = NULL; 6666 chan->sdu_len = 0; 6667 } 6668 break; 6669 } 6670 6671 if (err) { 6672 kfree_skb(skb); 6673 kfree_skb(chan->sdu); 6674 chan->sdu = NULL; 6675 chan->sdu_last_frag = NULL; 6676 chan->sdu_len = 0; 6677 } 6678 6679 return err; 6680 } 6681 6682 static int l2cap_resegment(struct l2cap_chan *chan) 6683 { 6684 /* Placeholder */ 6685 return 0; 6686 } 6687 6688 void l2cap_chan_busy(struct l2cap_chan *chan, int busy) 6689 { 6690 u8 event; 6691 6692 if (chan->mode != L2CAP_MODE_ERTM) 6693 return; 6694 6695 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR; 6696 l2cap_tx(chan, NULL, NULL, event); 6697 } 6698 6699 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan) 6700 { 6701 int err = 0; 6702 /* Pass sequential frames to l2cap_reassemble_sdu() 6703 * until a gap is encountered. 6704 */ 6705 6706 BT_DBG("chan %p", chan); 6707 6708 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 6709 struct sk_buff *skb; 6710 BT_DBG("Searching for skb with txseq %d (queue len %d)", 6711 chan->buffer_seq, skb_queue_len(&chan->srej_q)); 6712 6713 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq); 6714 6715 if (!skb) 6716 break; 6717 6718 skb_unlink(skb, &chan->srej_q); 6719 chan->buffer_seq = __next_seq(chan, chan->buffer_seq); 6720 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap); 6721 if (err) 6722 break; 6723 } 6724 6725 if (skb_queue_empty(&chan->srej_q)) { 6726 chan->rx_state = L2CAP_RX_STATE_RECV; 6727 l2cap_send_ack(chan); 6728 } 6729 6730 return err; 6731 } 6732 6733 static void l2cap_handle_srej(struct l2cap_chan *chan, 6734 struct l2cap_ctrl *control) 6735 { 6736 struct sk_buff *skb; 6737 6738 BT_DBG("chan %p, control %p", chan, control); 6739 6740 if (control->reqseq == chan->next_tx_seq) { 6741 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq); 6742 l2cap_send_disconn_req(chan, ECONNRESET); 6743 return; 6744 } 6745 6746 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq); 6747 6748 if (skb == NULL) { 6749 BT_DBG("Seq %d not available for retransmission", 6750 control->reqseq); 6751 return; 6752 } 6753 6754 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) { 6755 BT_DBG("Retry limit exceeded (%d)", chan->max_tx); 6756 l2cap_send_disconn_req(chan, ECONNRESET); 6757 return; 6758 } 6759 6760 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 6761 6762 if (control->poll) { 6763 l2cap_pass_to_tx(chan, control); 6764 6765 set_bit(CONN_SEND_FBIT, &chan->conn_state); 6766 l2cap_retransmit(chan, control); 6767 l2cap_ertm_send(chan); 6768 6769 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) { 6770 set_bit(CONN_SREJ_ACT, &chan->conn_state); 6771 chan->srej_save_reqseq = control->reqseq; 6772 } 6773 } else { 6774 l2cap_pass_to_tx_fbit(chan, control); 6775 6776 if (control->final) { 6777 if (chan->srej_save_reqseq != control->reqseq || 6778 !test_and_clear_bit(CONN_SREJ_ACT, 6779 &chan->conn_state)) 6780 l2cap_retransmit(chan, control); 6781 } else { 6782 l2cap_retransmit(chan, control); 6783 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) { 6784 set_bit(CONN_SREJ_ACT, &chan->conn_state); 6785 chan->srej_save_reqseq = control->reqseq; 6786 } 6787 } 6788 } 6789 } 6790 6791 static void l2cap_handle_rej(struct l2cap_chan *chan, 6792 struct l2cap_ctrl *control) 6793 { 6794 struct sk_buff *skb; 6795 6796 BT_DBG("chan %p, control %p", chan, control); 6797 6798 if (control->reqseq == chan->next_tx_seq) { 6799 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq); 6800 l2cap_send_disconn_req(chan, ECONNRESET); 6801 return; 6802 } 6803 6804 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq); 6805 6806 if (chan->max_tx && skb && 6807 bt_cb(skb)->l2cap.retries >= chan->max_tx) { 6808 BT_DBG("Retry limit exceeded (%d)", chan->max_tx); 6809 l2cap_send_disconn_req(chan, ECONNRESET); 6810 return; 6811 } 6812 6813 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 6814 6815 l2cap_pass_to_tx(chan, control); 6816 6817 if (control->final) { 6818 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state)) 6819 l2cap_retransmit_all(chan, control); 6820 } else { 6821 l2cap_retransmit_all(chan, control); 6822 l2cap_ertm_send(chan); 6823 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) 6824 set_bit(CONN_REJ_ACT, &chan->conn_state); 6825 } 6826 } 6827 6828 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq) 6829 { 6830 BT_DBG("chan %p, txseq %d", chan, txseq); 6831 6832 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq, 6833 chan->expected_tx_seq); 6834 6835 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) { 6836 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= 6837 chan->tx_win) { 6838 /* See notes below regarding "double poll" and 6839 * invalid packets. 6840 */ 6841 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) { 6842 BT_DBG("Invalid/Ignore - after SREJ"); 6843 return L2CAP_TXSEQ_INVALID_IGNORE; 6844 } else { 6845 BT_DBG("Invalid - in window after SREJ sent"); 6846 return L2CAP_TXSEQ_INVALID; 6847 } 6848 } 6849 6850 if (chan->srej_list.head == txseq) { 6851 BT_DBG("Expected SREJ"); 6852 return L2CAP_TXSEQ_EXPECTED_SREJ; 6853 } 6854 6855 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) { 6856 BT_DBG("Duplicate SREJ - txseq already stored"); 6857 return L2CAP_TXSEQ_DUPLICATE_SREJ; 6858 } 6859 6860 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) { 6861 BT_DBG("Unexpected SREJ - not requested"); 6862 return L2CAP_TXSEQ_UNEXPECTED_SREJ; 6863 } 6864 } 6865 6866 if (chan->expected_tx_seq == txseq) { 6867 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= 6868 chan->tx_win) { 6869 BT_DBG("Invalid - txseq outside tx window"); 6870 return L2CAP_TXSEQ_INVALID; 6871 } else { 6872 BT_DBG("Expected"); 6873 return L2CAP_TXSEQ_EXPECTED; 6874 } 6875 } 6876 6877 if (__seq_offset(chan, txseq, chan->last_acked_seq) < 6878 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) { 6879 BT_DBG("Duplicate - expected_tx_seq later than txseq"); 6880 return L2CAP_TXSEQ_DUPLICATE; 6881 } 6882 6883 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) { 6884 /* A source of invalid packets is a "double poll" condition, 6885 * where delays cause us to send multiple poll packets. If 6886 * the remote stack receives and processes both polls, 6887 * sequence numbers can wrap around in such a way that a 6888 * resent frame has a sequence number that looks like new data 6889 * with a sequence gap. This would trigger an erroneous SREJ 6890 * request. 6891 * 6892 * Fortunately, this is impossible with a tx window that's 6893 * less than half of the maximum sequence number, which allows 6894 * invalid frames to be safely ignored. 6895 * 6896 * With tx window sizes greater than half of the tx window 6897 * maximum, the frame is invalid and cannot be ignored. This 6898 * causes a disconnect. 6899 */ 6900 6901 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) { 6902 BT_DBG("Invalid/Ignore - txseq outside tx window"); 6903 return L2CAP_TXSEQ_INVALID_IGNORE; 6904 } else { 6905 BT_DBG("Invalid - txseq outside tx window"); 6906 return L2CAP_TXSEQ_INVALID; 6907 } 6908 } else { 6909 BT_DBG("Unexpected - txseq indicates missing frames"); 6910 return L2CAP_TXSEQ_UNEXPECTED; 6911 } 6912 } 6913 6914 static int l2cap_rx_state_recv(struct l2cap_chan *chan, 6915 struct l2cap_ctrl *control, 6916 struct sk_buff *skb, u8 event) 6917 { 6918 struct l2cap_ctrl local_control; 6919 int err = 0; 6920 bool skb_in_use = false; 6921 6922 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb, 6923 event); 6924 6925 switch (event) { 6926 case L2CAP_EV_RECV_IFRAME: 6927 switch (l2cap_classify_txseq(chan, control->txseq)) { 6928 case L2CAP_TXSEQ_EXPECTED: 6929 l2cap_pass_to_tx(chan, control); 6930 6931 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 6932 BT_DBG("Busy, discarding expected seq %d", 6933 control->txseq); 6934 break; 6935 } 6936 6937 chan->expected_tx_seq = __next_seq(chan, 6938 control->txseq); 6939 6940 chan->buffer_seq = chan->expected_tx_seq; 6941 skb_in_use = true; 6942 6943 /* l2cap_reassemble_sdu may free skb, hence invalidate 6944 * control, so make a copy in advance to use it after 6945 * l2cap_reassemble_sdu returns and to avoid the race 6946 * condition, for example: 6947 * 6948 * The current thread calls: 6949 * l2cap_reassemble_sdu 6950 * chan->ops->recv == l2cap_sock_recv_cb 6951 * __sock_queue_rcv_skb 6952 * Another thread calls: 6953 * bt_sock_recvmsg 6954 * skb_recv_datagram 6955 * skb_free_datagram 6956 * Then the current thread tries to access control, but 6957 * it was freed by skb_free_datagram. 6958 */ 6959 local_control = *control; 6960 err = l2cap_reassemble_sdu(chan, skb, control); 6961 if (err) 6962 break; 6963 6964 if (local_control.final) { 6965 if (!test_and_clear_bit(CONN_REJ_ACT, 6966 &chan->conn_state)) { 6967 local_control.final = 0; 6968 l2cap_retransmit_all(chan, &local_control); 6969 l2cap_ertm_send(chan); 6970 } 6971 } 6972 6973 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) 6974 l2cap_send_ack(chan); 6975 break; 6976 case L2CAP_TXSEQ_UNEXPECTED: 6977 l2cap_pass_to_tx(chan, control); 6978 6979 /* Can't issue SREJ frames in the local busy state. 6980 * Drop this frame, it will be seen as missing 6981 * when local busy is exited. 6982 */ 6983 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) { 6984 BT_DBG("Busy, discarding unexpected seq %d", 6985 control->txseq); 6986 break; 6987 } 6988 6989 /* There was a gap in the sequence, so an SREJ 6990 * must be sent for each missing frame. The 6991 * current frame is stored for later use. 6992 */ 6993 skb_queue_tail(&chan->srej_q, skb); 6994 skb_in_use = true; 6995 BT_DBG("Queued %p (queue len %d)", skb, 6996 skb_queue_len(&chan->srej_q)); 6997 6998 clear_bit(CONN_SREJ_ACT, &chan->conn_state); 6999 l2cap_seq_list_clear(&chan->srej_list); 7000 l2cap_send_srej(chan, control->txseq); 7001 7002 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT; 7003 break; 7004 case L2CAP_TXSEQ_DUPLICATE: 7005 l2cap_pass_to_tx(chan, control); 7006 break; 7007 case L2CAP_TXSEQ_INVALID_IGNORE: 7008 break; 7009 case L2CAP_TXSEQ_INVALID: 7010 default: 7011 l2cap_send_disconn_req(chan, ECONNRESET); 7012 break; 7013 } 7014 break; 7015 case L2CAP_EV_RECV_RR: 7016 l2cap_pass_to_tx(chan, control); 7017 if (control->final) { 7018 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7019 7020 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) && 7021 !__chan_is_moving(chan)) { 7022 control->final = 0; 7023 l2cap_retransmit_all(chan, control); 7024 } 7025 7026 l2cap_ertm_send(chan); 7027 } else if (control->poll) { 7028 l2cap_send_i_or_rr_or_rnr(chan); 7029 } else { 7030 if (test_and_clear_bit(CONN_REMOTE_BUSY, 7031 &chan->conn_state) && 7032 chan->unacked_frames) 7033 __set_retrans_timer(chan); 7034 7035 l2cap_ertm_send(chan); 7036 } 7037 break; 7038 case L2CAP_EV_RECV_RNR: 7039 set_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7040 l2cap_pass_to_tx(chan, control); 7041 if (control && control->poll) { 7042 set_bit(CONN_SEND_FBIT, &chan->conn_state); 7043 l2cap_send_rr_or_rnr(chan, 0); 7044 } 7045 __clear_retrans_timer(chan); 7046 l2cap_seq_list_clear(&chan->retrans_list); 7047 break; 7048 case L2CAP_EV_RECV_REJ: 7049 l2cap_handle_rej(chan, control); 7050 break; 7051 case L2CAP_EV_RECV_SREJ: 7052 l2cap_handle_srej(chan, control); 7053 break; 7054 default: 7055 break; 7056 } 7057 7058 if (skb && !skb_in_use) { 7059 BT_DBG("Freeing %p", skb); 7060 kfree_skb(skb); 7061 } 7062 7063 return err; 7064 } 7065 7066 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan, 7067 struct l2cap_ctrl *control, 7068 struct sk_buff *skb, u8 event) 7069 { 7070 int err = 0; 7071 u16 txseq = control->txseq; 7072 bool skb_in_use = false; 7073 7074 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb, 7075 event); 7076 7077 switch (event) { 7078 case L2CAP_EV_RECV_IFRAME: 7079 switch (l2cap_classify_txseq(chan, txseq)) { 7080 case L2CAP_TXSEQ_EXPECTED: 7081 /* Keep frame for reassembly later */ 7082 l2cap_pass_to_tx(chan, control); 7083 skb_queue_tail(&chan->srej_q, skb); 7084 skb_in_use = true; 7085 BT_DBG("Queued %p (queue len %d)", skb, 7086 skb_queue_len(&chan->srej_q)); 7087 7088 chan->expected_tx_seq = __next_seq(chan, txseq); 7089 break; 7090 case L2CAP_TXSEQ_EXPECTED_SREJ: 7091 l2cap_seq_list_pop(&chan->srej_list); 7092 7093 l2cap_pass_to_tx(chan, control); 7094 skb_queue_tail(&chan->srej_q, skb); 7095 skb_in_use = true; 7096 BT_DBG("Queued %p (queue len %d)", skb, 7097 skb_queue_len(&chan->srej_q)); 7098 7099 err = l2cap_rx_queued_iframes(chan); 7100 if (err) 7101 break; 7102 7103 break; 7104 case L2CAP_TXSEQ_UNEXPECTED: 7105 /* Got a frame that can't be reassembled yet. 7106 * Save it for later, and send SREJs to cover 7107 * the missing frames. 7108 */ 7109 skb_queue_tail(&chan->srej_q, skb); 7110 skb_in_use = true; 7111 BT_DBG("Queued %p (queue len %d)", skb, 7112 skb_queue_len(&chan->srej_q)); 7113 7114 l2cap_pass_to_tx(chan, control); 7115 l2cap_send_srej(chan, control->txseq); 7116 break; 7117 case L2CAP_TXSEQ_UNEXPECTED_SREJ: 7118 /* This frame was requested with an SREJ, but 7119 * some expected retransmitted frames are 7120 * missing. Request retransmission of missing 7121 * SREJ'd frames. 7122 */ 7123 skb_queue_tail(&chan->srej_q, skb); 7124 skb_in_use = true; 7125 BT_DBG("Queued %p (queue len %d)", skb, 7126 skb_queue_len(&chan->srej_q)); 7127 7128 l2cap_pass_to_tx(chan, control); 7129 l2cap_send_srej_list(chan, control->txseq); 7130 break; 7131 case L2CAP_TXSEQ_DUPLICATE_SREJ: 7132 /* We've already queued this frame. Drop this copy. */ 7133 l2cap_pass_to_tx(chan, control); 7134 break; 7135 case L2CAP_TXSEQ_DUPLICATE: 7136 /* Expecting a later sequence number, so this frame 7137 * was already received. Ignore it completely. 7138 */ 7139 break; 7140 case L2CAP_TXSEQ_INVALID_IGNORE: 7141 break; 7142 case L2CAP_TXSEQ_INVALID: 7143 default: 7144 l2cap_send_disconn_req(chan, ECONNRESET); 7145 break; 7146 } 7147 break; 7148 case L2CAP_EV_RECV_RR: 7149 l2cap_pass_to_tx(chan, control); 7150 if (control->final) { 7151 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7152 7153 if (!test_and_clear_bit(CONN_REJ_ACT, 7154 &chan->conn_state)) { 7155 control->final = 0; 7156 l2cap_retransmit_all(chan, control); 7157 } 7158 7159 l2cap_ertm_send(chan); 7160 } else if (control->poll) { 7161 if (test_and_clear_bit(CONN_REMOTE_BUSY, 7162 &chan->conn_state) && 7163 chan->unacked_frames) { 7164 __set_retrans_timer(chan); 7165 } 7166 7167 set_bit(CONN_SEND_FBIT, &chan->conn_state); 7168 l2cap_send_srej_tail(chan); 7169 } else { 7170 if (test_and_clear_bit(CONN_REMOTE_BUSY, 7171 &chan->conn_state) && 7172 chan->unacked_frames) 7173 __set_retrans_timer(chan); 7174 7175 l2cap_send_ack(chan); 7176 } 7177 break; 7178 case L2CAP_EV_RECV_RNR: 7179 set_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7180 l2cap_pass_to_tx(chan, control); 7181 if (control->poll) { 7182 l2cap_send_srej_tail(chan); 7183 } else { 7184 struct l2cap_ctrl rr_control; 7185 memset(&rr_control, 0, sizeof(rr_control)); 7186 rr_control.sframe = 1; 7187 rr_control.super = L2CAP_SUPER_RR; 7188 rr_control.reqseq = chan->buffer_seq; 7189 l2cap_send_sframe(chan, &rr_control); 7190 } 7191 7192 break; 7193 case L2CAP_EV_RECV_REJ: 7194 l2cap_handle_rej(chan, control); 7195 break; 7196 case L2CAP_EV_RECV_SREJ: 7197 l2cap_handle_srej(chan, control); 7198 break; 7199 } 7200 7201 if (skb && !skb_in_use) { 7202 BT_DBG("Freeing %p", skb); 7203 kfree_skb(skb); 7204 } 7205 7206 return err; 7207 } 7208 7209 static int l2cap_finish_move(struct l2cap_chan *chan) 7210 { 7211 BT_DBG("chan %p", chan); 7212 7213 chan->rx_state = L2CAP_RX_STATE_RECV; 7214 7215 if (chan->hs_hcon) 7216 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu; 7217 else 7218 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu; 7219 7220 return l2cap_resegment(chan); 7221 } 7222 7223 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan, 7224 struct l2cap_ctrl *control, 7225 struct sk_buff *skb, u8 event) 7226 { 7227 int err; 7228 7229 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb, 7230 event); 7231 7232 if (!control->poll) 7233 return -EPROTO; 7234 7235 l2cap_process_reqseq(chan, control->reqseq); 7236 7237 if (!skb_queue_empty(&chan->tx_q)) 7238 chan->tx_send_head = skb_peek(&chan->tx_q); 7239 else 7240 chan->tx_send_head = NULL; 7241 7242 /* Rewind next_tx_seq to the point expected 7243 * by the receiver. 7244 */ 7245 chan->next_tx_seq = control->reqseq; 7246 chan->unacked_frames = 0; 7247 7248 err = l2cap_finish_move(chan); 7249 if (err) 7250 return err; 7251 7252 set_bit(CONN_SEND_FBIT, &chan->conn_state); 7253 l2cap_send_i_or_rr_or_rnr(chan); 7254 7255 if (event == L2CAP_EV_RECV_IFRAME) 7256 return -EPROTO; 7257 7258 return l2cap_rx_state_recv(chan, control, NULL, event); 7259 } 7260 7261 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan, 7262 struct l2cap_ctrl *control, 7263 struct sk_buff *skb, u8 event) 7264 { 7265 int err; 7266 7267 if (!control->final) 7268 return -EPROTO; 7269 7270 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); 7271 7272 chan->rx_state = L2CAP_RX_STATE_RECV; 7273 l2cap_process_reqseq(chan, control->reqseq); 7274 7275 if (!skb_queue_empty(&chan->tx_q)) 7276 chan->tx_send_head = skb_peek(&chan->tx_q); 7277 else 7278 chan->tx_send_head = NULL; 7279 7280 /* Rewind next_tx_seq to the point expected 7281 * by the receiver. 7282 */ 7283 chan->next_tx_seq = control->reqseq; 7284 chan->unacked_frames = 0; 7285 7286 if (chan->hs_hcon) 7287 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu; 7288 else 7289 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu; 7290 7291 err = l2cap_resegment(chan); 7292 7293 if (!err) 7294 err = l2cap_rx_state_recv(chan, control, skb, event); 7295 7296 return err; 7297 } 7298 7299 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq) 7300 { 7301 /* Make sure reqseq is for a packet that has been sent but not acked */ 7302 u16 unacked; 7303 7304 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq); 7305 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked; 7306 } 7307 7308 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control, 7309 struct sk_buff *skb, u8 event) 7310 { 7311 int err = 0; 7312 7313 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan, 7314 control, skb, event, chan->rx_state); 7315 7316 if (__valid_reqseq(chan, control->reqseq)) { 7317 switch (chan->rx_state) { 7318 case L2CAP_RX_STATE_RECV: 7319 err = l2cap_rx_state_recv(chan, control, skb, event); 7320 break; 7321 case L2CAP_RX_STATE_SREJ_SENT: 7322 err = l2cap_rx_state_srej_sent(chan, control, skb, 7323 event); 7324 break; 7325 case L2CAP_RX_STATE_WAIT_P: 7326 err = l2cap_rx_state_wait_p(chan, control, skb, event); 7327 break; 7328 case L2CAP_RX_STATE_WAIT_F: 7329 err = l2cap_rx_state_wait_f(chan, control, skb, event); 7330 break; 7331 default: 7332 /* shut it down */ 7333 break; 7334 } 7335 } else { 7336 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d", 7337 control->reqseq, chan->next_tx_seq, 7338 chan->expected_ack_seq); 7339 l2cap_send_disconn_req(chan, ECONNRESET); 7340 } 7341 7342 return err; 7343 } 7344 7345 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control, 7346 struct sk_buff *skb) 7347 { 7348 /* l2cap_reassemble_sdu may free skb, hence invalidate control, so store 7349 * the txseq field in advance to use it after l2cap_reassemble_sdu 7350 * returns and to avoid the race condition, for example: 7351 * 7352 * The current thread calls: 7353 * l2cap_reassemble_sdu 7354 * chan->ops->recv == l2cap_sock_recv_cb 7355 * __sock_queue_rcv_skb 7356 * Another thread calls: 7357 * bt_sock_recvmsg 7358 * skb_recv_datagram 7359 * skb_free_datagram 7360 * Then the current thread tries to access control, but it was freed by 7361 * skb_free_datagram. 7362 */ 7363 u16 txseq = control->txseq; 7364 7365 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb, 7366 chan->rx_state); 7367 7368 if (l2cap_classify_txseq(chan, txseq) == L2CAP_TXSEQ_EXPECTED) { 7369 l2cap_pass_to_tx(chan, control); 7370 7371 BT_DBG("buffer_seq %u->%u", chan->buffer_seq, 7372 __next_seq(chan, chan->buffer_seq)); 7373 7374 chan->buffer_seq = __next_seq(chan, chan->buffer_seq); 7375 7376 l2cap_reassemble_sdu(chan, skb, control); 7377 } else { 7378 if (chan->sdu) { 7379 kfree_skb(chan->sdu); 7380 chan->sdu = NULL; 7381 } 7382 chan->sdu_last_frag = NULL; 7383 chan->sdu_len = 0; 7384 7385 if (skb) { 7386 BT_DBG("Freeing %p", skb); 7387 kfree_skb(skb); 7388 } 7389 } 7390 7391 chan->last_acked_seq = txseq; 7392 chan->expected_tx_seq = __next_seq(chan, txseq); 7393 7394 return 0; 7395 } 7396 7397 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) 7398 { 7399 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap; 7400 u16 len; 7401 u8 event; 7402 7403 __unpack_control(chan, skb); 7404 7405 len = skb->len; 7406 7407 /* 7408 * We can just drop the corrupted I-frame here. 7409 * Receiver will miss it and start proper recovery 7410 * procedures and ask for retransmission. 7411 */ 7412 if (l2cap_check_fcs(chan, skb)) 7413 goto drop; 7414 7415 if (!control->sframe && control->sar == L2CAP_SAR_START) 7416 len -= L2CAP_SDULEN_SIZE; 7417 7418 if (chan->fcs == L2CAP_FCS_CRC16) 7419 len -= L2CAP_FCS_SIZE; 7420 7421 if (len > chan->mps) { 7422 l2cap_send_disconn_req(chan, ECONNRESET); 7423 goto drop; 7424 } 7425 7426 if (chan->ops->filter) { 7427 if (chan->ops->filter(chan, skb)) 7428 goto drop; 7429 } 7430 7431 if (!control->sframe) { 7432 int err; 7433 7434 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d", 7435 control->sar, control->reqseq, control->final, 7436 control->txseq); 7437 7438 /* Validate F-bit - F=0 always valid, F=1 only 7439 * valid in TX WAIT_F 7440 */ 7441 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F) 7442 goto drop; 7443 7444 if (chan->mode != L2CAP_MODE_STREAMING) { 7445 event = L2CAP_EV_RECV_IFRAME; 7446 err = l2cap_rx(chan, control, skb, event); 7447 } else { 7448 err = l2cap_stream_rx(chan, control, skb); 7449 } 7450 7451 if (err) 7452 l2cap_send_disconn_req(chan, ECONNRESET); 7453 } else { 7454 const u8 rx_func_to_event[4] = { 7455 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ, 7456 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ 7457 }; 7458 7459 /* Only I-frames are expected in streaming mode */ 7460 if (chan->mode == L2CAP_MODE_STREAMING) 7461 goto drop; 7462 7463 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d", 7464 control->reqseq, control->final, control->poll, 7465 control->super); 7466 7467 if (len != 0) { 7468 BT_ERR("Trailing bytes: %d in sframe", len); 7469 l2cap_send_disconn_req(chan, ECONNRESET); 7470 goto drop; 7471 } 7472 7473 /* Validate F and P bits */ 7474 if (control->final && (control->poll || 7475 chan->tx_state != L2CAP_TX_STATE_WAIT_F)) 7476 goto drop; 7477 7478 event = rx_func_to_event[control->super]; 7479 if (l2cap_rx(chan, control, skb, event)) 7480 l2cap_send_disconn_req(chan, ECONNRESET); 7481 } 7482 7483 return 0; 7484 7485 drop: 7486 kfree_skb(skb); 7487 return 0; 7488 } 7489 7490 static void l2cap_chan_le_send_credits(struct l2cap_chan *chan) 7491 { 7492 struct l2cap_conn *conn = chan->conn; 7493 struct l2cap_le_credits pkt; 7494 u16 return_credits; 7495 7496 return_credits = (chan->imtu / chan->mps) + 1; 7497 7498 if (chan->rx_credits >= return_credits) 7499 return; 7500 7501 return_credits -= chan->rx_credits; 7502 7503 BT_DBG("chan %p returning %u credits to sender", chan, return_credits); 7504 7505 chan->rx_credits += return_credits; 7506 7507 pkt.cid = cpu_to_le16(chan->scid); 7508 pkt.credits = cpu_to_le16(return_credits); 7509 7510 chan->ident = l2cap_get_ident(conn); 7511 7512 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt); 7513 } 7514 7515 static int l2cap_ecred_recv(struct l2cap_chan *chan, struct sk_buff *skb) 7516 { 7517 int err; 7518 7519 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len); 7520 7521 /* Wait recv to confirm reception before updating the credits */ 7522 err = chan->ops->recv(chan, skb); 7523 7524 /* Update credits whenever an SDU is received */ 7525 l2cap_chan_le_send_credits(chan); 7526 7527 return err; 7528 } 7529 7530 static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) 7531 { 7532 int err; 7533 7534 if (!chan->rx_credits) { 7535 BT_ERR("No credits to receive LE L2CAP data"); 7536 l2cap_send_disconn_req(chan, ECONNRESET); 7537 return -ENOBUFS; 7538 } 7539 7540 if (chan->imtu < skb->len) { 7541 BT_ERR("Too big LE L2CAP PDU"); 7542 return -ENOBUFS; 7543 } 7544 7545 chan->rx_credits--; 7546 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits); 7547 7548 /* Update if remote had run out of credits, this should only happens 7549 * if the remote is not using the entire MPS. 7550 */ 7551 if (!chan->rx_credits) 7552 l2cap_chan_le_send_credits(chan); 7553 7554 err = 0; 7555 7556 if (!chan->sdu) { 7557 u16 sdu_len; 7558 7559 sdu_len = get_unaligned_le16(skb->data); 7560 skb_pull(skb, L2CAP_SDULEN_SIZE); 7561 7562 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u", 7563 sdu_len, skb->len, chan->imtu); 7564 7565 if (sdu_len > chan->imtu) { 7566 BT_ERR("Too big LE L2CAP SDU length received"); 7567 err = -EMSGSIZE; 7568 goto failed; 7569 } 7570 7571 if (skb->len > sdu_len) { 7572 BT_ERR("Too much LE L2CAP data received"); 7573 err = -EINVAL; 7574 goto failed; 7575 } 7576 7577 if (skb->len == sdu_len) 7578 return l2cap_ecred_recv(chan, skb); 7579 7580 chan->sdu = skb; 7581 chan->sdu_len = sdu_len; 7582 chan->sdu_last_frag = skb; 7583 7584 /* Detect if remote is not able to use the selected MPS */ 7585 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) { 7586 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE; 7587 7588 /* Adjust the number of credits */ 7589 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len); 7590 chan->mps = mps_len; 7591 l2cap_chan_le_send_credits(chan); 7592 } 7593 7594 return 0; 7595 } 7596 7597 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u", 7598 chan->sdu->len, skb->len, chan->sdu_len); 7599 7600 if (chan->sdu->len + skb->len > chan->sdu_len) { 7601 BT_ERR("Too much LE L2CAP data received"); 7602 err = -EINVAL; 7603 goto failed; 7604 } 7605 7606 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag); 7607 skb = NULL; 7608 7609 if (chan->sdu->len == chan->sdu_len) { 7610 err = l2cap_ecred_recv(chan, chan->sdu); 7611 if (!err) { 7612 chan->sdu = NULL; 7613 chan->sdu_last_frag = NULL; 7614 chan->sdu_len = 0; 7615 } 7616 } 7617 7618 failed: 7619 if (err) { 7620 kfree_skb(skb); 7621 kfree_skb(chan->sdu); 7622 chan->sdu = NULL; 7623 chan->sdu_last_frag = NULL; 7624 chan->sdu_len = 0; 7625 } 7626 7627 /* We can't return an error here since we took care of the skb 7628 * freeing internally. An error return would cause the caller to 7629 * do a double-free of the skb. 7630 */ 7631 return 0; 7632 } 7633 7634 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid, 7635 struct sk_buff *skb) 7636 { 7637 struct l2cap_chan *chan; 7638 7639 chan = l2cap_get_chan_by_scid(conn, cid); 7640 if (!chan) { 7641 if (cid == L2CAP_CID_A2MP) { 7642 chan = a2mp_channel_create(conn, skb); 7643 if (!chan) { 7644 kfree_skb(skb); 7645 return; 7646 } 7647 7648 l2cap_chan_hold(chan); 7649 l2cap_chan_lock(chan); 7650 } else { 7651 BT_DBG("unknown cid 0x%4.4x", cid); 7652 /* Drop packet and return */ 7653 kfree_skb(skb); 7654 return; 7655 } 7656 } 7657 7658 BT_DBG("chan %p, len %d", chan, skb->len); 7659 7660 /* If we receive data on a fixed channel before the info req/rsp 7661 * procedure is done simply assume that the channel is supported 7662 * and mark it as ready. 7663 */ 7664 if (chan->chan_type == L2CAP_CHAN_FIXED) 7665 l2cap_chan_ready(chan); 7666 7667 if (chan->state != BT_CONNECTED) 7668 goto drop; 7669 7670 switch (chan->mode) { 7671 case L2CAP_MODE_LE_FLOWCTL: 7672 case L2CAP_MODE_EXT_FLOWCTL: 7673 if (l2cap_ecred_data_rcv(chan, skb) < 0) 7674 goto drop; 7675 7676 goto done; 7677 7678 case L2CAP_MODE_BASIC: 7679 /* If socket recv buffers overflows we drop data here 7680 * which is *bad* because L2CAP has to be reliable. 7681 * But we don't have any other choice. L2CAP doesn't 7682 * provide flow control mechanism. */ 7683 7684 if (chan->imtu < skb->len) { 7685 BT_ERR("Dropping L2CAP data: receive buffer overflow"); 7686 goto drop; 7687 } 7688 7689 if (!chan->ops->recv(chan, skb)) 7690 goto done; 7691 break; 7692 7693 case L2CAP_MODE_ERTM: 7694 case L2CAP_MODE_STREAMING: 7695 l2cap_data_rcv(chan, skb); 7696 goto done; 7697 7698 default: 7699 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode); 7700 break; 7701 } 7702 7703 drop: 7704 kfree_skb(skb); 7705 7706 done: 7707 l2cap_chan_unlock(chan); 7708 l2cap_chan_put(chan); 7709 } 7710 7711 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm, 7712 struct sk_buff *skb) 7713 { 7714 struct hci_conn *hcon = conn->hcon; 7715 struct l2cap_chan *chan; 7716 7717 if (hcon->type != ACL_LINK) 7718 goto free_skb; 7719 7720 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst, 7721 ACL_LINK); 7722 if (!chan) 7723 goto free_skb; 7724 7725 BT_DBG("chan %p, len %d", chan, skb->len); 7726 7727 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED) 7728 goto drop; 7729 7730 if (chan->imtu < skb->len) 7731 goto drop; 7732 7733 /* Store remote BD_ADDR and PSM for msg_name */ 7734 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst); 7735 bt_cb(skb)->l2cap.psm = psm; 7736 7737 if (!chan->ops->recv(chan, skb)) { 7738 l2cap_chan_put(chan); 7739 return; 7740 } 7741 7742 drop: 7743 l2cap_chan_put(chan); 7744 free_skb: 7745 kfree_skb(skb); 7746 } 7747 7748 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb) 7749 { 7750 struct l2cap_hdr *lh = (void *) skb->data; 7751 struct hci_conn *hcon = conn->hcon; 7752 u16 cid, len; 7753 __le16 psm; 7754 7755 if (hcon->state != BT_CONNECTED) { 7756 BT_DBG("queueing pending rx skb"); 7757 skb_queue_tail(&conn->pending_rx, skb); 7758 return; 7759 } 7760 7761 skb_pull(skb, L2CAP_HDR_SIZE); 7762 cid = __le16_to_cpu(lh->cid); 7763 len = __le16_to_cpu(lh->len); 7764 7765 if (len != skb->len) { 7766 kfree_skb(skb); 7767 return; 7768 } 7769 7770 /* Since we can't actively block incoming LE connections we must 7771 * at least ensure that we ignore incoming data from them. 7772 */ 7773 if (hcon->type == LE_LINK && 7774 hci_bdaddr_list_lookup(&hcon->hdev->reject_list, &hcon->dst, 7775 bdaddr_dst_type(hcon))) { 7776 kfree_skb(skb); 7777 return; 7778 } 7779 7780 BT_DBG("len %d, cid 0x%4.4x", len, cid); 7781 7782 switch (cid) { 7783 case L2CAP_CID_SIGNALING: 7784 l2cap_sig_channel(conn, skb); 7785 break; 7786 7787 case L2CAP_CID_CONN_LESS: 7788 psm = get_unaligned((__le16 *) skb->data); 7789 skb_pull(skb, L2CAP_PSMLEN_SIZE); 7790 l2cap_conless_channel(conn, psm, skb); 7791 break; 7792 7793 case L2CAP_CID_LE_SIGNALING: 7794 l2cap_le_sig_channel(conn, skb); 7795 break; 7796 7797 default: 7798 l2cap_data_channel(conn, cid, skb); 7799 break; 7800 } 7801 } 7802 7803 static void process_pending_rx(struct work_struct *work) 7804 { 7805 struct l2cap_conn *conn = container_of(work, struct l2cap_conn, 7806 pending_rx_work); 7807 struct sk_buff *skb; 7808 7809 BT_DBG(""); 7810 7811 while ((skb = skb_dequeue(&conn->pending_rx))) 7812 l2cap_recv_frame(conn, skb); 7813 } 7814 7815 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon) 7816 { 7817 struct l2cap_conn *conn = hcon->l2cap_data; 7818 struct hci_chan *hchan; 7819 7820 if (conn) 7821 return conn; 7822 7823 hchan = hci_chan_create(hcon); 7824 if (!hchan) 7825 return NULL; 7826 7827 conn = kzalloc(sizeof(*conn), GFP_KERNEL); 7828 if (!conn) { 7829 hci_chan_del(hchan); 7830 return NULL; 7831 } 7832 7833 kref_init(&conn->ref); 7834 hcon->l2cap_data = conn; 7835 conn->hcon = hci_conn_get(hcon); 7836 conn->hchan = hchan; 7837 7838 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan); 7839 7840 switch (hcon->type) { 7841 case LE_LINK: 7842 if (hcon->hdev->le_mtu) { 7843 conn->mtu = hcon->hdev->le_mtu; 7844 break; 7845 } 7846 fallthrough; 7847 default: 7848 conn->mtu = hcon->hdev->acl_mtu; 7849 break; 7850 } 7851 7852 conn->feat_mask = 0; 7853 7854 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS; 7855 7856 if (hcon->type == ACL_LINK && 7857 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED)) 7858 conn->local_fixed_chan |= L2CAP_FC_A2MP; 7859 7860 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) && 7861 (bredr_sc_enabled(hcon->hdev) || 7862 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP))) 7863 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR; 7864 7865 mutex_init(&conn->ident_lock); 7866 mutex_init(&conn->chan_lock); 7867 7868 INIT_LIST_HEAD(&conn->chan_l); 7869 INIT_LIST_HEAD(&conn->users); 7870 7871 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout); 7872 7873 skb_queue_head_init(&conn->pending_rx); 7874 INIT_WORK(&conn->pending_rx_work, process_pending_rx); 7875 INIT_DELAYED_WORK(&conn->id_addr_timer, l2cap_conn_update_id_addr); 7876 7877 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM; 7878 7879 return conn; 7880 } 7881 7882 static bool is_valid_psm(u16 psm, u8 dst_type) 7883 { 7884 if (!psm) 7885 return false; 7886 7887 if (bdaddr_type_is_le(dst_type)) 7888 return (psm <= 0x00ff); 7889 7890 /* PSM must be odd and lsb of upper byte must be 0 */ 7891 return ((psm & 0x0101) == 0x0001); 7892 } 7893 7894 struct l2cap_chan_data { 7895 struct l2cap_chan *chan; 7896 struct pid *pid; 7897 int count; 7898 }; 7899 7900 static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data) 7901 { 7902 struct l2cap_chan_data *d = data; 7903 struct pid *pid; 7904 7905 if (chan == d->chan) 7906 return; 7907 7908 if (!test_bit(FLAG_DEFER_SETUP, &chan->flags)) 7909 return; 7910 7911 pid = chan->ops->get_peer_pid(chan); 7912 7913 /* Only count deferred channels with the same PID/PSM */ 7914 if (d->pid != pid || chan->psm != d->chan->psm || chan->ident || 7915 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT) 7916 return; 7917 7918 d->count++; 7919 } 7920 7921 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, 7922 bdaddr_t *dst, u8 dst_type) 7923 { 7924 struct l2cap_conn *conn; 7925 struct hci_conn *hcon; 7926 struct hci_dev *hdev; 7927 int err; 7928 7929 BT_DBG("%pMR -> %pMR (type %u) psm 0x%4.4x mode 0x%2.2x", &chan->src, 7930 dst, dst_type, __le16_to_cpu(psm), chan->mode); 7931 7932 hdev = hci_get_route(dst, &chan->src, chan->src_type); 7933 if (!hdev) 7934 return -EHOSTUNREACH; 7935 7936 hci_dev_lock(hdev); 7937 7938 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid && 7939 chan->chan_type != L2CAP_CHAN_RAW) { 7940 err = -EINVAL; 7941 goto done; 7942 } 7943 7944 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) { 7945 err = -EINVAL; 7946 goto done; 7947 } 7948 7949 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) { 7950 err = -EINVAL; 7951 goto done; 7952 } 7953 7954 switch (chan->mode) { 7955 case L2CAP_MODE_BASIC: 7956 break; 7957 case L2CAP_MODE_LE_FLOWCTL: 7958 break; 7959 case L2CAP_MODE_EXT_FLOWCTL: 7960 if (!enable_ecred) { 7961 err = -EOPNOTSUPP; 7962 goto done; 7963 } 7964 break; 7965 case L2CAP_MODE_ERTM: 7966 case L2CAP_MODE_STREAMING: 7967 if (!disable_ertm) 7968 break; 7969 fallthrough; 7970 default: 7971 err = -EOPNOTSUPP; 7972 goto done; 7973 } 7974 7975 switch (chan->state) { 7976 case BT_CONNECT: 7977 case BT_CONNECT2: 7978 case BT_CONFIG: 7979 /* Already connecting */ 7980 err = 0; 7981 goto done; 7982 7983 case BT_CONNECTED: 7984 /* Already connected */ 7985 err = -EISCONN; 7986 goto done; 7987 7988 case BT_OPEN: 7989 case BT_BOUND: 7990 /* Can connect */ 7991 break; 7992 7993 default: 7994 err = -EBADFD; 7995 goto done; 7996 } 7997 7998 /* Set destination address and psm */ 7999 bacpy(&chan->dst, dst); 8000 chan->dst_type = dst_type; 8001 8002 chan->psm = psm; 8003 chan->dcid = cid; 8004 8005 if (bdaddr_type_is_le(dst_type)) { 8006 /* Convert from L2CAP channel address type to HCI address type 8007 */ 8008 if (dst_type == BDADDR_LE_PUBLIC) 8009 dst_type = ADDR_LE_DEV_PUBLIC; 8010 else 8011 dst_type = ADDR_LE_DEV_RANDOM; 8012 8013 if (hci_dev_test_flag(hdev, HCI_ADVERTISING)) 8014 hcon = hci_connect_le(hdev, dst, dst_type, false, 8015 chan->sec_level, 8016 HCI_LE_CONN_TIMEOUT, 8017 HCI_ROLE_SLAVE); 8018 else 8019 hcon = hci_connect_le_scan(hdev, dst, dst_type, 8020 chan->sec_level, 8021 HCI_LE_CONN_TIMEOUT, 8022 CONN_REASON_L2CAP_CHAN); 8023 8024 } else { 8025 u8 auth_type = l2cap_get_auth_type(chan); 8026 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type, 8027 CONN_REASON_L2CAP_CHAN); 8028 } 8029 8030 if (IS_ERR(hcon)) { 8031 err = PTR_ERR(hcon); 8032 goto done; 8033 } 8034 8035 conn = l2cap_conn_add(hcon); 8036 if (!conn) { 8037 hci_conn_drop(hcon); 8038 err = -ENOMEM; 8039 goto done; 8040 } 8041 8042 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) { 8043 struct l2cap_chan_data data; 8044 8045 data.chan = chan; 8046 data.pid = chan->ops->get_peer_pid(chan); 8047 data.count = 1; 8048 8049 l2cap_chan_list(conn, l2cap_chan_by_pid, &data); 8050 8051 /* Check if there isn't too many channels being connected */ 8052 if (data.count > L2CAP_ECRED_CONN_SCID_MAX) { 8053 hci_conn_drop(hcon); 8054 err = -EPROTO; 8055 goto done; 8056 } 8057 } 8058 8059 mutex_lock(&conn->chan_lock); 8060 l2cap_chan_lock(chan); 8061 8062 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) { 8063 hci_conn_drop(hcon); 8064 err = -EBUSY; 8065 goto chan_unlock; 8066 } 8067 8068 /* Update source addr of the socket */ 8069 bacpy(&chan->src, &hcon->src); 8070 chan->src_type = bdaddr_src_type(hcon); 8071 8072 __l2cap_chan_add(conn, chan); 8073 8074 /* l2cap_chan_add takes its own ref so we can drop this one */ 8075 hci_conn_drop(hcon); 8076 8077 l2cap_state_change(chan, BT_CONNECT); 8078 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan)); 8079 8080 /* Release chan->sport so that it can be reused by other 8081 * sockets (as it's only used for listening sockets). 8082 */ 8083 write_lock(&chan_list_lock); 8084 chan->sport = 0; 8085 write_unlock(&chan_list_lock); 8086 8087 if (hcon->state == BT_CONNECTED) { 8088 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 8089 __clear_chan_timer(chan); 8090 if (l2cap_chan_check_security(chan, true)) 8091 l2cap_state_change(chan, BT_CONNECTED); 8092 } else 8093 l2cap_do_start(chan); 8094 } 8095 8096 err = 0; 8097 8098 chan_unlock: 8099 l2cap_chan_unlock(chan); 8100 mutex_unlock(&conn->chan_lock); 8101 done: 8102 hci_dev_unlock(hdev); 8103 hci_dev_put(hdev); 8104 return err; 8105 } 8106 EXPORT_SYMBOL_GPL(l2cap_chan_connect); 8107 8108 static void l2cap_ecred_reconfigure(struct l2cap_chan *chan) 8109 { 8110 struct l2cap_conn *conn = chan->conn; 8111 struct { 8112 struct l2cap_ecred_reconf_req req; 8113 __le16 scid; 8114 } pdu; 8115 8116 pdu.req.mtu = cpu_to_le16(chan->imtu); 8117 pdu.req.mps = cpu_to_le16(chan->mps); 8118 pdu.scid = cpu_to_le16(chan->scid); 8119 8120 chan->ident = l2cap_get_ident(conn); 8121 8122 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_RECONF_REQ, 8123 sizeof(pdu), &pdu); 8124 } 8125 8126 int l2cap_chan_reconfigure(struct l2cap_chan *chan, __u16 mtu) 8127 { 8128 if (chan->imtu > mtu) 8129 return -EINVAL; 8130 8131 BT_DBG("chan %p mtu 0x%4.4x", chan, mtu); 8132 8133 chan->imtu = mtu; 8134 8135 l2cap_ecred_reconfigure(chan); 8136 8137 return 0; 8138 } 8139 8140 /* ---- L2CAP interface with lower layer (HCI) ---- */ 8141 8142 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr) 8143 { 8144 int exact = 0, lm1 = 0, lm2 = 0; 8145 struct l2cap_chan *c; 8146 8147 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr); 8148 8149 /* Find listening sockets and check their link_mode */ 8150 read_lock(&chan_list_lock); 8151 list_for_each_entry(c, &chan_list, global_l) { 8152 if (c->state != BT_LISTEN) 8153 continue; 8154 8155 if (!bacmp(&c->src, &hdev->bdaddr)) { 8156 lm1 |= HCI_LM_ACCEPT; 8157 if (test_bit(FLAG_ROLE_SWITCH, &c->flags)) 8158 lm1 |= HCI_LM_MASTER; 8159 exact++; 8160 } else if (!bacmp(&c->src, BDADDR_ANY)) { 8161 lm2 |= HCI_LM_ACCEPT; 8162 if (test_bit(FLAG_ROLE_SWITCH, &c->flags)) 8163 lm2 |= HCI_LM_MASTER; 8164 } 8165 } 8166 read_unlock(&chan_list_lock); 8167 8168 return exact ? lm1 : lm2; 8169 } 8170 8171 /* Find the next fixed channel in BT_LISTEN state, continue iteration 8172 * from an existing channel in the list or from the beginning of the 8173 * global list (by passing NULL as first parameter). 8174 */ 8175 static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c, 8176 struct hci_conn *hcon) 8177 { 8178 u8 src_type = bdaddr_src_type(hcon); 8179 8180 read_lock(&chan_list_lock); 8181 8182 if (c) 8183 c = list_next_entry(c, global_l); 8184 else 8185 c = list_entry(chan_list.next, typeof(*c), global_l); 8186 8187 list_for_each_entry_from(c, &chan_list, global_l) { 8188 if (c->chan_type != L2CAP_CHAN_FIXED) 8189 continue; 8190 if (c->state != BT_LISTEN) 8191 continue; 8192 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY)) 8193 continue; 8194 if (src_type != c->src_type) 8195 continue; 8196 8197 c = l2cap_chan_hold_unless_zero(c); 8198 read_unlock(&chan_list_lock); 8199 return c; 8200 } 8201 8202 read_unlock(&chan_list_lock); 8203 8204 return NULL; 8205 } 8206 8207 static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status) 8208 { 8209 struct hci_dev *hdev = hcon->hdev; 8210 struct l2cap_conn *conn; 8211 struct l2cap_chan *pchan; 8212 u8 dst_type; 8213 8214 if (hcon->type != ACL_LINK && hcon->type != LE_LINK) 8215 return; 8216 8217 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status); 8218 8219 if (status) { 8220 l2cap_conn_del(hcon, bt_to_errno(status)); 8221 return; 8222 } 8223 8224 conn = l2cap_conn_add(hcon); 8225 if (!conn) 8226 return; 8227 8228 dst_type = bdaddr_dst_type(hcon); 8229 8230 /* If device is blocked, do not create channels for it */ 8231 if (hci_bdaddr_list_lookup(&hdev->reject_list, &hcon->dst, dst_type)) 8232 return; 8233 8234 /* Find fixed channels and notify them of the new connection. We 8235 * use multiple individual lookups, continuing each time where 8236 * we left off, because the list lock would prevent calling the 8237 * potentially sleeping l2cap_chan_lock() function. 8238 */ 8239 pchan = l2cap_global_fixed_chan(NULL, hcon); 8240 while (pchan) { 8241 struct l2cap_chan *chan, *next; 8242 8243 /* Client fixed channels should override server ones */ 8244 if (__l2cap_get_chan_by_dcid(conn, pchan->scid)) 8245 goto next; 8246 8247 l2cap_chan_lock(pchan); 8248 chan = pchan->ops->new_connection(pchan); 8249 if (chan) { 8250 bacpy(&chan->src, &hcon->src); 8251 bacpy(&chan->dst, &hcon->dst); 8252 chan->src_type = bdaddr_src_type(hcon); 8253 chan->dst_type = dst_type; 8254 8255 __l2cap_chan_add(conn, chan); 8256 } 8257 8258 l2cap_chan_unlock(pchan); 8259 next: 8260 next = l2cap_global_fixed_chan(pchan, hcon); 8261 l2cap_chan_put(pchan); 8262 pchan = next; 8263 } 8264 8265 l2cap_conn_ready(conn); 8266 } 8267 8268 int l2cap_disconn_ind(struct hci_conn *hcon) 8269 { 8270 struct l2cap_conn *conn = hcon->l2cap_data; 8271 8272 BT_DBG("hcon %p", hcon); 8273 8274 if (!conn) 8275 return HCI_ERROR_REMOTE_USER_TERM; 8276 return conn->disc_reason; 8277 } 8278 8279 static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason) 8280 { 8281 if (hcon->type != ACL_LINK && hcon->type != LE_LINK) 8282 return; 8283 8284 BT_DBG("hcon %p reason %d", hcon, reason); 8285 8286 l2cap_conn_del(hcon, bt_to_errno(reason)); 8287 } 8288 8289 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt) 8290 { 8291 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) 8292 return; 8293 8294 if (encrypt == 0x00) { 8295 if (chan->sec_level == BT_SECURITY_MEDIUM) { 8296 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT); 8297 } else if (chan->sec_level == BT_SECURITY_HIGH || 8298 chan->sec_level == BT_SECURITY_FIPS) 8299 l2cap_chan_close(chan, ECONNREFUSED); 8300 } else { 8301 if (chan->sec_level == BT_SECURITY_MEDIUM) 8302 __clear_chan_timer(chan); 8303 } 8304 } 8305 8306 static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) 8307 { 8308 struct l2cap_conn *conn = hcon->l2cap_data; 8309 struct l2cap_chan *chan; 8310 8311 if (!conn) 8312 return; 8313 8314 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt); 8315 8316 mutex_lock(&conn->chan_lock); 8317 8318 list_for_each_entry(chan, &conn->chan_l, list) { 8319 l2cap_chan_lock(chan); 8320 8321 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid, 8322 state_to_string(chan->state)); 8323 8324 if (chan->scid == L2CAP_CID_A2MP) { 8325 l2cap_chan_unlock(chan); 8326 continue; 8327 } 8328 8329 if (!status && encrypt) 8330 chan->sec_level = hcon->sec_level; 8331 8332 if (!__l2cap_no_conn_pending(chan)) { 8333 l2cap_chan_unlock(chan); 8334 continue; 8335 } 8336 8337 if (!status && (chan->state == BT_CONNECTED || 8338 chan->state == BT_CONFIG)) { 8339 chan->ops->resume(chan); 8340 l2cap_check_encryption(chan, encrypt); 8341 l2cap_chan_unlock(chan); 8342 continue; 8343 } 8344 8345 if (chan->state == BT_CONNECT) { 8346 if (!status && l2cap_check_enc_key_size(hcon)) 8347 l2cap_start_connection(chan); 8348 else 8349 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); 8350 } else if (chan->state == BT_CONNECT2 && 8351 !(chan->mode == L2CAP_MODE_EXT_FLOWCTL || 8352 chan->mode == L2CAP_MODE_LE_FLOWCTL)) { 8353 struct l2cap_conn_rsp rsp; 8354 __u16 res, stat; 8355 8356 if (!status && l2cap_check_enc_key_size(hcon)) { 8357 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { 8358 res = L2CAP_CR_PEND; 8359 stat = L2CAP_CS_AUTHOR_PEND; 8360 chan->ops->defer(chan); 8361 } else { 8362 l2cap_state_change(chan, BT_CONFIG); 8363 res = L2CAP_CR_SUCCESS; 8364 stat = L2CAP_CS_NO_INFO; 8365 } 8366 } else { 8367 l2cap_state_change(chan, BT_DISCONN); 8368 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); 8369 res = L2CAP_CR_SEC_BLOCK; 8370 stat = L2CAP_CS_NO_INFO; 8371 } 8372 8373 rsp.scid = cpu_to_le16(chan->dcid); 8374 rsp.dcid = cpu_to_le16(chan->scid); 8375 rsp.result = cpu_to_le16(res); 8376 rsp.status = cpu_to_le16(stat); 8377 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, 8378 sizeof(rsp), &rsp); 8379 8380 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) && 8381 res == L2CAP_CR_SUCCESS) { 8382 char buf[128]; 8383 set_bit(CONF_REQ_SENT, &chan->conf_state); 8384 l2cap_send_cmd(conn, l2cap_get_ident(conn), 8385 L2CAP_CONF_REQ, 8386 l2cap_build_conf_req(chan, buf, sizeof(buf)), 8387 buf); 8388 chan->num_conf_req++; 8389 } 8390 } 8391 8392 l2cap_chan_unlock(chan); 8393 } 8394 8395 mutex_unlock(&conn->chan_lock); 8396 } 8397 8398 /* Append fragment into frame respecting the maximum len of rx_skb */ 8399 static int l2cap_recv_frag(struct l2cap_conn *conn, struct sk_buff *skb, 8400 u16 len) 8401 { 8402 if (!conn->rx_skb) { 8403 /* Allocate skb for the complete frame (with header) */ 8404 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL); 8405 if (!conn->rx_skb) 8406 return -ENOMEM; 8407 /* Init rx_len */ 8408 conn->rx_len = len; 8409 } 8410 8411 /* Copy as much as the rx_skb can hold */ 8412 len = min_t(u16, len, skb->len); 8413 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, len), len); 8414 skb_pull(skb, len); 8415 conn->rx_len -= len; 8416 8417 return len; 8418 } 8419 8420 static int l2cap_recv_len(struct l2cap_conn *conn, struct sk_buff *skb) 8421 { 8422 struct sk_buff *rx_skb; 8423 int len; 8424 8425 /* Append just enough to complete the header */ 8426 len = l2cap_recv_frag(conn, skb, L2CAP_LEN_SIZE - conn->rx_skb->len); 8427 8428 /* If header could not be read just continue */ 8429 if (len < 0 || conn->rx_skb->len < L2CAP_LEN_SIZE) 8430 return len; 8431 8432 rx_skb = conn->rx_skb; 8433 len = get_unaligned_le16(rx_skb->data); 8434 8435 /* Check if rx_skb has enough space to received all fragments */ 8436 if (len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE) <= skb_tailroom(rx_skb)) { 8437 /* Update expected len */ 8438 conn->rx_len = len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE); 8439 return L2CAP_LEN_SIZE; 8440 } 8441 8442 /* Reset conn->rx_skb since it will need to be reallocated in order to 8443 * fit all fragments. 8444 */ 8445 conn->rx_skb = NULL; 8446 8447 /* Reallocates rx_skb using the exact expected length */ 8448 len = l2cap_recv_frag(conn, rx_skb, 8449 len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE)); 8450 kfree_skb(rx_skb); 8451 8452 return len; 8453 } 8454 8455 static void l2cap_recv_reset(struct l2cap_conn *conn) 8456 { 8457 kfree_skb(conn->rx_skb); 8458 conn->rx_skb = NULL; 8459 conn->rx_len = 0; 8460 } 8461 8462 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags) 8463 { 8464 struct l2cap_conn *conn = hcon->l2cap_data; 8465 int len; 8466 8467 /* For AMP controller do not create l2cap conn */ 8468 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY) 8469 goto drop; 8470 8471 if (!conn) 8472 conn = l2cap_conn_add(hcon); 8473 8474 if (!conn) 8475 goto drop; 8476 8477 BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags); 8478 8479 switch (flags) { 8480 case ACL_START: 8481 case ACL_START_NO_FLUSH: 8482 case ACL_COMPLETE: 8483 if (conn->rx_skb) { 8484 BT_ERR("Unexpected start frame (len %d)", skb->len); 8485 l2cap_recv_reset(conn); 8486 l2cap_conn_unreliable(conn, ECOMM); 8487 } 8488 8489 /* Start fragment may not contain the L2CAP length so just 8490 * copy the initial byte when that happens and use conn->mtu as 8491 * expected length. 8492 */ 8493 if (skb->len < L2CAP_LEN_SIZE) { 8494 l2cap_recv_frag(conn, skb, conn->mtu); 8495 break; 8496 } 8497 8498 len = get_unaligned_le16(skb->data) + L2CAP_HDR_SIZE; 8499 8500 if (len == skb->len) { 8501 /* Complete frame received */ 8502 l2cap_recv_frame(conn, skb); 8503 return; 8504 } 8505 8506 BT_DBG("Start: total len %d, frag len %u", len, skb->len); 8507 8508 if (skb->len > len) { 8509 BT_ERR("Frame is too long (len %u, expected len %d)", 8510 skb->len, len); 8511 l2cap_conn_unreliable(conn, ECOMM); 8512 goto drop; 8513 } 8514 8515 /* Append fragment into frame (with header) */ 8516 if (l2cap_recv_frag(conn, skb, len) < 0) 8517 goto drop; 8518 8519 break; 8520 8521 case ACL_CONT: 8522 BT_DBG("Cont: frag len %u (expecting %u)", skb->len, conn->rx_len); 8523 8524 if (!conn->rx_skb) { 8525 BT_ERR("Unexpected continuation frame (len %d)", skb->len); 8526 l2cap_conn_unreliable(conn, ECOMM); 8527 goto drop; 8528 } 8529 8530 /* Complete the L2CAP length if it has not been read */ 8531 if (conn->rx_skb->len < L2CAP_LEN_SIZE) { 8532 if (l2cap_recv_len(conn, skb) < 0) { 8533 l2cap_conn_unreliable(conn, ECOMM); 8534 goto drop; 8535 } 8536 8537 /* Header still could not be read just continue */ 8538 if (conn->rx_skb->len < L2CAP_LEN_SIZE) 8539 break; 8540 } 8541 8542 if (skb->len > conn->rx_len) { 8543 BT_ERR("Fragment is too long (len %u, expected %u)", 8544 skb->len, conn->rx_len); 8545 l2cap_recv_reset(conn); 8546 l2cap_conn_unreliable(conn, ECOMM); 8547 goto drop; 8548 } 8549 8550 /* Append fragment into frame (with header) */ 8551 l2cap_recv_frag(conn, skb, skb->len); 8552 8553 if (!conn->rx_len) { 8554 /* Complete frame received. l2cap_recv_frame 8555 * takes ownership of the skb so set the global 8556 * rx_skb pointer to NULL first. 8557 */ 8558 struct sk_buff *rx_skb = conn->rx_skb; 8559 conn->rx_skb = NULL; 8560 l2cap_recv_frame(conn, rx_skb); 8561 } 8562 break; 8563 } 8564 8565 drop: 8566 kfree_skb(skb); 8567 } 8568 8569 static struct hci_cb l2cap_cb = { 8570 .name = "L2CAP", 8571 .connect_cfm = l2cap_connect_cfm, 8572 .disconn_cfm = l2cap_disconn_cfm, 8573 .security_cfm = l2cap_security_cfm, 8574 }; 8575 8576 static int l2cap_debugfs_show(struct seq_file *f, void *p) 8577 { 8578 struct l2cap_chan *c; 8579 8580 read_lock(&chan_list_lock); 8581 8582 list_for_each_entry(c, &chan_list, global_l) { 8583 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n", 8584 &c->src, c->src_type, &c->dst, c->dst_type, 8585 c->state, __le16_to_cpu(c->psm), 8586 c->scid, c->dcid, c->imtu, c->omtu, 8587 c->sec_level, c->mode); 8588 } 8589 8590 read_unlock(&chan_list_lock); 8591 8592 return 0; 8593 } 8594 8595 DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs); 8596 8597 static struct dentry *l2cap_debugfs; 8598 8599 int __init l2cap_init(void) 8600 { 8601 int err; 8602 8603 err = l2cap_init_sockets(); 8604 if (err < 0) 8605 return err; 8606 8607 hci_register_cb(&l2cap_cb); 8608 8609 if (IS_ERR_OR_NULL(bt_debugfs)) 8610 return 0; 8611 8612 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs, 8613 NULL, &l2cap_debugfs_fops); 8614 8615 return 0; 8616 } 8617 8618 void l2cap_exit(void) 8619 { 8620 debugfs_remove(l2cap_debugfs); 8621 hci_unregister_cb(&l2cap_cb); 8622 l2cap_cleanup_sockets(); 8623 } 8624 8625 module_param(disable_ertm, bool, 0644); 8626 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode"); 8627 8628 module_param(enable_ecred, bool, 0644); 8629 MODULE_PARM_DESC(enable_ecred, "Enable enhanced credit flow control mode"); 8630