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 8 Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com> 9 10 This program is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License version 2 as 12 published by the Free Software Foundation; 13 14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 15 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. 17 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY 18 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 19 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 20 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 21 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 22 23 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 24 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 25 SOFTWARE IS DISCLAIMED. 26 */ 27 28 /* Bluetooth L2CAP sockets. */ 29 30 #include <linux/module.h> 31 #include <linux/export.h> 32 #include <linux/sched/signal.h> 33 34 #include <net/bluetooth/bluetooth.h> 35 #include <net/bluetooth/hci_core.h> 36 #include <net/bluetooth/l2cap.h> 37 38 #include "smp.h" 39 40 static struct bt_sock_list l2cap_sk_list = { 41 .lock = __RW_LOCK_UNLOCKED(l2cap_sk_list.lock) 42 }; 43 44 static const struct proto_ops l2cap_sock_ops; 45 static void l2cap_sock_init(struct sock *sk, struct sock *parent); 46 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, 47 int proto, gfp_t prio, int kern); 48 49 bool l2cap_is_socket(struct socket *sock) 50 { 51 return sock && sock->ops == &l2cap_sock_ops; 52 } 53 EXPORT_SYMBOL(l2cap_is_socket); 54 55 static int l2cap_validate_bredr_psm(u16 psm) 56 { 57 /* PSM must be odd and lsb of upper byte must be 0 */ 58 if ((psm & 0x0101) != 0x0001) 59 return -EINVAL; 60 61 /* Restrict usage of well-known PSMs */ 62 if (psm < L2CAP_PSM_DYN_START && !capable(CAP_NET_BIND_SERVICE)) 63 return -EACCES; 64 65 return 0; 66 } 67 68 static int l2cap_validate_le_psm(u16 psm) 69 { 70 /* Valid LE_PSM ranges are defined only until 0x00ff */ 71 if (psm > L2CAP_PSM_LE_DYN_END) 72 return -EINVAL; 73 74 /* Restrict fixed, SIG assigned PSM values to CAP_NET_BIND_SERVICE */ 75 if (psm < L2CAP_PSM_LE_DYN_START && !capable(CAP_NET_BIND_SERVICE)) 76 return -EACCES; 77 78 return 0; 79 } 80 81 static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen) 82 { 83 struct sock *sk = sock->sk; 84 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 85 struct sockaddr_l2 la; 86 int len, err = 0; 87 88 BT_DBG("sk %p", sk); 89 90 if (!addr || alen < offsetofend(struct sockaddr, sa_family) || 91 addr->sa_family != AF_BLUETOOTH) 92 return -EINVAL; 93 94 memset(&la, 0, sizeof(la)); 95 len = min_t(unsigned int, sizeof(la), alen); 96 memcpy(&la, addr, len); 97 98 if (la.l2_cid && la.l2_psm) 99 return -EINVAL; 100 101 if (!bdaddr_type_is_valid(la.l2_bdaddr_type)) 102 return -EINVAL; 103 104 if (bdaddr_type_is_le(la.l2_bdaddr_type)) { 105 /* We only allow ATT user space socket */ 106 if (la.l2_cid && 107 la.l2_cid != cpu_to_le16(L2CAP_CID_ATT)) 108 return -EINVAL; 109 } 110 111 lock_sock(sk); 112 113 if (sk->sk_state != BT_OPEN) { 114 err = -EBADFD; 115 goto done; 116 } 117 118 if (la.l2_psm) { 119 __u16 psm = __le16_to_cpu(la.l2_psm); 120 121 if (la.l2_bdaddr_type == BDADDR_BREDR) 122 err = l2cap_validate_bredr_psm(psm); 123 else 124 err = l2cap_validate_le_psm(psm); 125 126 if (err) 127 goto done; 128 } 129 130 bacpy(&chan->src, &la.l2_bdaddr); 131 chan->src_type = la.l2_bdaddr_type; 132 133 if (la.l2_cid) 134 err = l2cap_add_scid(chan, __le16_to_cpu(la.l2_cid)); 135 else 136 err = l2cap_add_psm(chan, &la.l2_bdaddr, la.l2_psm); 137 138 if (err < 0) 139 goto done; 140 141 switch (chan->chan_type) { 142 case L2CAP_CHAN_CONN_LESS: 143 if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_3DSP) 144 chan->sec_level = BT_SECURITY_SDP; 145 break; 146 case L2CAP_CHAN_CONN_ORIENTED: 147 if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_SDP || 148 __le16_to_cpu(la.l2_psm) == L2CAP_PSM_RFCOMM) 149 chan->sec_level = BT_SECURITY_SDP; 150 break; 151 case L2CAP_CHAN_RAW: 152 chan->sec_level = BT_SECURITY_SDP; 153 break; 154 case L2CAP_CHAN_FIXED: 155 /* Fixed channels default to the L2CAP core not holding a 156 * hci_conn reference for them. For fixed channels mapping to 157 * L2CAP sockets we do want to hold a reference so set the 158 * appropriate flag to request it. 159 */ 160 set_bit(FLAG_HOLD_HCI_CONN, &chan->flags); 161 break; 162 } 163 164 if (chan->psm && bdaddr_type_is_le(chan->src_type)) 165 chan->mode = L2CAP_MODE_LE_FLOWCTL; 166 167 chan->state = BT_BOUND; 168 sk->sk_state = BT_BOUND; 169 170 done: 171 release_sock(sk); 172 return err; 173 } 174 175 static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, 176 int alen, int flags) 177 { 178 struct sock *sk = sock->sk; 179 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 180 struct sockaddr_l2 la; 181 int len, err = 0; 182 183 BT_DBG("sk %p", sk); 184 185 if (!addr || alen < offsetofend(struct sockaddr, sa_family) || 186 addr->sa_family != AF_BLUETOOTH) 187 return -EINVAL; 188 189 memset(&la, 0, sizeof(la)); 190 len = min_t(unsigned int, sizeof(la), alen); 191 memcpy(&la, addr, len); 192 193 if (la.l2_cid && la.l2_psm) 194 return -EINVAL; 195 196 if (!bdaddr_type_is_valid(la.l2_bdaddr_type)) 197 return -EINVAL; 198 199 /* Check that the socket wasn't bound to something that 200 * conflicts with the address given to connect(). If chan->src 201 * is BDADDR_ANY it means bind() was never used, in which case 202 * chan->src_type and la.l2_bdaddr_type do not need to match. 203 */ 204 if (chan->src_type == BDADDR_BREDR && bacmp(&chan->src, BDADDR_ANY) && 205 bdaddr_type_is_le(la.l2_bdaddr_type)) { 206 /* Old user space versions will try to incorrectly bind 207 * the ATT socket using BDADDR_BREDR. We need to accept 208 * this and fix up the source address type only when 209 * both the source CID and destination CID indicate 210 * ATT. Anything else is an invalid combination. 211 */ 212 if (chan->scid != L2CAP_CID_ATT || 213 la.l2_cid != cpu_to_le16(L2CAP_CID_ATT)) 214 return -EINVAL; 215 216 /* We don't have the hdev available here to make a 217 * better decision on random vs public, but since all 218 * user space versions that exhibit this issue anyway do 219 * not support random local addresses assuming public 220 * here is good enough. 221 */ 222 chan->src_type = BDADDR_LE_PUBLIC; 223 } 224 225 if (chan->src_type != BDADDR_BREDR && la.l2_bdaddr_type == BDADDR_BREDR) 226 return -EINVAL; 227 228 if (bdaddr_type_is_le(la.l2_bdaddr_type)) { 229 /* We only allow ATT user space socket */ 230 if (la.l2_cid && 231 la.l2_cid != cpu_to_le16(L2CAP_CID_ATT)) 232 return -EINVAL; 233 } 234 235 if (chan->psm && bdaddr_type_is_le(chan->src_type) && !chan->mode) 236 chan->mode = L2CAP_MODE_LE_FLOWCTL; 237 238 err = l2cap_chan_connect(chan, la.l2_psm, __le16_to_cpu(la.l2_cid), 239 &la.l2_bdaddr, la.l2_bdaddr_type); 240 if (err) 241 return err; 242 243 lock_sock(sk); 244 245 err = bt_sock_wait_state(sk, BT_CONNECTED, 246 sock_sndtimeo(sk, flags & O_NONBLOCK)); 247 248 release_sock(sk); 249 250 return err; 251 } 252 253 static int l2cap_sock_listen(struct socket *sock, int backlog) 254 { 255 struct sock *sk = sock->sk; 256 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 257 int err = 0; 258 259 BT_DBG("sk %p backlog %d", sk, backlog); 260 261 lock_sock(sk); 262 263 if (sk->sk_state != BT_BOUND) { 264 err = -EBADFD; 265 goto done; 266 } 267 268 if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM) { 269 err = -EINVAL; 270 goto done; 271 } 272 273 switch (chan->mode) { 274 case L2CAP_MODE_BASIC: 275 case L2CAP_MODE_LE_FLOWCTL: 276 break; 277 case L2CAP_MODE_EXT_FLOWCTL: 278 if (!enable_ecred) { 279 err = -EOPNOTSUPP; 280 goto done; 281 } 282 break; 283 case L2CAP_MODE_ERTM: 284 case L2CAP_MODE_STREAMING: 285 if (!disable_ertm) 286 break; 287 fallthrough; 288 default: 289 err = -EOPNOTSUPP; 290 goto done; 291 } 292 293 sk->sk_max_ack_backlog = backlog; 294 sk->sk_ack_backlog = 0; 295 296 /* Listening channels need to use nested locking in order not to 297 * cause lockdep warnings when the created child channels end up 298 * being locked in the same thread as the parent channel. 299 */ 300 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); 301 302 chan->state = BT_LISTEN; 303 sk->sk_state = BT_LISTEN; 304 305 done: 306 release_sock(sk); 307 return err; 308 } 309 310 static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, 311 int flags, bool kern) 312 { 313 DEFINE_WAIT_FUNC(wait, woken_wake_function); 314 struct sock *sk = sock->sk, *nsk; 315 long timeo; 316 int err = 0; 317 318 lock_sock_nested(sk, L2CAP_NESTING_PARENT); 319 320 timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); 321 322 BT_DBG("sk %p timeo %ld", sk, timeo); 323 324 /* Wait for an incoming connection. (wake-one). */ 325 add_wait_queue_exclusive(sk_sleep(sk), &wait); 326 while (1) { 327 if (sk->sk_state != BT_LISTEN) { 328 err = -EBADFD; 329 break; 330 } 331 332 nsk = bt_accept_dequeue(sk, newsock); 333 if (nsk) 334 break; 335 336 if (!timeo) { 337 err = -EAGAIN; 338 break; 339 } 340 341 if (signal_pending(current)) { 342 err = sock_intr_errno(timeo); 343 break; 344 } 345 346 release_sock(sk); 347 348 timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo); 349 350 lock_sock_nested(sk, L2CAP_NESTING_PARENT); 351 } 352 remove_wait_queue(sk_sleep(sk), &wait); 353 354 if (err) 355 goto done; 356 357 newsock->state = SS_CONNECTED; 358 359 BT_DBG("new socket %p", nsk); 360 361 done: 362 release_sock(sk); 363 return err; 364 } 365 366 static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr, 367 int peer) 368 { 369 struct sockaddr_l2 *la = (struct sockaddr_l2 *) addr; 370 struct sock *sk = sock->sk; 371 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 372 373 BT_DBG("sock %p, sk %p", sock, sk); 374 375 if (peer && sk->sk_state != BT_CONNECTED && 376 sk->sk_state != BT_CONNECT && sk->sk_state != BT_CONNECT2 && 377 sk->sk_state != BT_CONFIG) 378 return -ENOTCONN; 379 380 memset(la, 0, sizeof(struct sockaddr_l2)); 381 addr->sa_family = AF_BLUETOOTH; 382 383 la->l2_psm = chan->psm; 384 385 if (peer) { 386 bacpy(&la->l2_bdaddr, &chan->dst); 387 la->l2_cid = cpu_to_le16(chan->dcid); 388 la->l2_bdaddr_type = chan->dst_type; 389 } else { 390 bacpy(&la->l2_bdaddr, &chan->src); 391 la->l2_cid = cpu_to_le16(chan->scid); 392 la->l2_bdaddr_type = chan->src_type; 393 } 394 395 return sizeof(struct sockaddr_l2); 396 } 397 398 static int l2cap_get_mode(struct l2cap_chan *chan) 399 { 400 switch (chan->mode) { 401 case L2CAP_MODE_BASIC: 402 return BT_MODE_BASIC; 403 case L2CAP_MODE_ERTM: 404 return BT_MODE_ERTM; 405 case L2CAP_MODE_STREAMING: 406 return BT_MODE_STREAMING; 407 case L2CAP_MODE_LE_FLOWCTL: 408 return BT_MODE_LE_FLOWCTL; 409 case L2CAP_MODE_EXT_FLOWCTL: 410 return BT_MODE_EXT_FLOWCTL; 411 } 412 413 return -EINVAL; 414 } 415 416 static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, 417 char __user *optval, int __user *optlen) 418 { 419 struct sock *sk = sock->sk; 420 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 421 struct l2cap_options opts; 422 struct l2cap_conninfo cinfo; 423 int len, err = 0; 424 u32 opt; 425 426 BT_DBG("sk %p", sk); 427 428 if (get_user(len, optlen)) 429 return -EFAULT; 430 431 lock_sock(sk); 432 433 switch (optname) { 434 case L2CAP_OPTIONS: 435 /* LE sockets should use BT_SNDMTU/BT_RCVMTU, but since 436 * legacy ATT code depends on getsockopt for 437 * L2CAP_OPTIONS we need to let this pass. 438 */ 439 if (bdaddr_type_is_le(chan->src_type) && 440 chan->scid != L2CAP_CID_ATT) { 441 err = -EINVAL; 442 break; 443 } 444 445 /* Only BR/EDR modes are supported here */ 446 switch (chan->mode) { 447 case L2CAP_MODE_BASIC: 448 case L2CAP_MODE_ERTM: 449 case L2CAP_MODE_STREAMING: 450 break; 451 default: 452 err = -EINVAL; 453 break; 454 } 455 456 if (err < 0) 457 break; 458 459 memset(&opts, 0, sizeof(opts)); 460 opts.imtu = chan->imtu; 461 opts.omtu = chan->omtu; 462 opts.flush_to = chan->flush_to; 463 opts.mode = chan->mode; 464 opts.fcs = chan->fcs; 465 opts.max_tx = chan->max_tx; 466 opts.txwin_size = chan->tx_win; 467 468 BT_DBG("mode 0x%2.2x", chan->mode); 469 470 len = min_t(unsigned int, len, sizeof(opts)); 471 if (copy_to_user(optval, (char *) &opts, len)) 472 err = -EFAULT; 473 474 break; 475 476 case L2CAP_LM: 477 switch (chan->sec_level) { 478 case BT_SECURITY_LOW: 479 opt = L2CAP_LM_AUTH; 480 break; 481 case BT_SECURITY_MEDIUM: 482 opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT; 483 break; 484 case BT_SECURITY_HIGH: 485 opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT | 486 L2CAP_LM_SECURE; 487 break; 488 case BT_SECURITY_FIPS: 489 opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT | 490 L2CAP_LM_SECURE | L2CAP_LM_FIPS; 491 break; 492 default: 493 opt = 0; 494 break; 495 } 496 497 if (test_bit(FLAG_ROLE_SWITCH, &chan->flags)) 498 opt |= L2CAP_LM_MASTER; 499 500 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags)) 501 opt |= L2CAP_LM_RELIABLE; 502 503 if (put_user(opt, (u32 __user *) optval)) 504 err = -EFAULT; 505 506 break; 507 508 case L2CAP_CONNINFO: 509 if (sk->sk_state != BT_CONNECTED && 510 !(sk->sk_state == BT_CONNECT2 && 511 test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))) { 512 err = -ENOTCONN; 513 break; 514 } 515 516 memset(&cinfo, 0, sizeof(cinfo)); 517 cinfo.hci_handle = chan->conn->hcon->handle; 518 memcpy(cinfo.dev_class, chan->conn->hcon->dev_class, 3); 519 520 len = min_t(unsigned int, len, sizeof(cinfo)); 521 if (copy_to_user(optval, (char *) &cinfo, len)) 522 err = -EFAULT; 523 524 break; 525 526 default: 527 err = -ENOPROTOOPT; 528 break; 529 } 530 531 release_sock(sk); 532 return err; 533 } 534 535 static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, 536 char __user *optval, int __user *optlen) 537 { 538 struct sock *sk = sock->sk; 539 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 540 struct bt_security sec; 541 struct bt_power pwr; 542 u32 phys; 543 int len, mode, err = 0; 544 545 BT_DBG("sk %p", sk); 546 547 if (level == SOL_L2CAP) 548 return l2cap_sock_getsockopt_old(sock, optname, optval, optlen); 549 550 if (level != SOL_BLUETOOTH) 551 return -ENOPROTOOPT; 552 553 if (get_user(len, optlen)) 554 return -EFAULT; 555 556 lock_sock(sk); 557 558 switch (optname) { 559 case BT_SECURITY: 560 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED && 561 chan->chan_type != L2CAP_CHAN_FIXED && 562 chan->chan_type != L2CAP_CHAN_RAW) { 563 err = -EINVAL; 564 break; 565 } 566 567 memset(&sec, 0, sizeof(sec)); 568 if (chan->conn) { 569 sec.level = chan->conn->hcon->sec_level; 570 571 if (sk->sk_state == BT_CONNECTED) 572 sec.key_size = chan->conn->hcon->enc_key_size; 573 } else { 574 sec.level = chan->sec_level; 575 } 576 577 len = min_t(unsigned int, len, sizeof(sec)); 578 if (copy_to_user(optval, (char *) &sec, len)) 579 err = -EFAULT; 580 581 break; 582 583 case BT_DEFER_SETUP: 584 if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) { 585 err = -EINVAL; 586 break; 587 } 588 589 if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags), 590 (u32 __user *) optval)) 591 err = -EFAULT; 592 593 break; 594 595 case BT_FLUSHABLE: 596 if (put_user(test_bit(FLAG_FLUSHABLE, &chan->flags), 597 (u32 __user *) optval)) 598 err = -EFAULT; 599 600 break; 601 602 case BT_POWER: 603 if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM 604 && sk->sk_type != SOCK_RAW) { 605 err = -EINVAL; 606 break; 607 } 608 609 pwr.force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags); 610 611 len = min_t(unsigned int, len, sizeof(pwr)); 612 if (copy_to_user(optval, (char *) &pwr, len)) 613 err = -EFAULT; 614 615 break; 616 617 case BT_CHANNEL_POLICY: 618 if (put_user(chan->chan_policy, (u32 __user *) optval)) 619 err = -EFAULT; 620 break; 621 622 case BT_SNDMTU: 623 if (!bdaddr_type_is_le(chan->src_type)) { 624 err = -EINVAL; 625 break; 626 } 627 628 if (sk->sk_state != BT_CONNECTED) { 629 err = -ENOTCONN; 630 break; 631 } 632 633 if (put_user(chan->omtu, (u16 __user *) optval)) 634 err = -EFAULT; 635 break; 636 637 case BT_RCVMTU: 638 if (!bdaddr_type_is_le(chan->src_type)) { 639 err = -EINVAL; 640 break; 641 } 642 643 if (put_user(chan->imtu, (u16 __user *) optval)) 644 err = -EFAULT; 645 break; 646 647 case BT_PHY: 648 if (sk->sk_state != BT_CONNECTED) { 649 err = -ENOTCONN; 650 break; 651 } 652 653 phys = hci_conn_get_phy(chan->conn->hcon); 654 655 if (put_user(phys, (u32 __user *) optval)) 656 err = -EFAULT; 657 break; 658 659 case BT_MODE: 660 if (!enable_ecred) { 661 err = -ENOPROTOOPT; 662 break; 663 } 664 665 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 666 err = -EINVAL; 667 break; 668 } 669 670 mode = l2cap_get_mode(chan); 671 if (mode < 0) { 672 err = mode; 673 break; 674 } 675 676 if (put_user(mode, (u8 __user *) optval)) 677 err = -EFAULT; 678 break; 679 680 default: 681 err = -ENOPROTOOPT; 682 break; 683 } 684 685 release_sock(sk); 686 return err; 687 } 688 689 static bool l2cap_valid_mtu(struct l2cap_chan *chan, u16 mtu) 690 { 691 switch (chan->scid) { 692 case L2CAP_CID_ATT: 693 if (mtu < L2CAP_LE_MIN_MTU) 694 return false; 695 break; 696 697 default: 698 if (mtu < L2CAP_DEFAULT_MIN_MTU) 699 return false; 700 } 701 702 return true; 703 } 704 705 static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, 706 sockptr_t optval, unsigned int optlen) 707 { 708 struct sock *sk = sock->sk; 709 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 710 struct l2cap_options opts; 711 int len, err = 0; 712 u32 opt; 713 714 BT_DBG("sk %p", sk); 715 716 lock_sock(sk); 717 718 switch (optname) { 719 case L2CAP_OPTIONS: 720 if (bdaddr_type_is_le(chan->src_type)) { 721 err = -EINVAL; 722 break; 723 } 724 725 if (sk->sk_state == BT_CONNECTED) { 726 err = -EINVAL; 727 break; 728 } 729 730 opts.imtu = chan->imtu; 731 opts.omtu = chan->omtu; 732 opts.flush_to = chan->flush_to; 733 opts.mode = chan->mode; 734 opts.fcs = chan->fcs; 735 opts.max_tx = chan->max_tx; 736 opts.txwin_size = chan->tx_win; 737 738 len = min_t(unsigned int, sizeof(opts), optlen); 739 if (copy_from_sockptr(&opts, optval, len)) { 740 err = -EFAULT; 741 break; 742 } 743 744 if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) { 745 err = -EINVAL; 746 break; 747 } 748 749 if (!l2cap_valid_mtu(chan, opts.imtu)) { 750 err = -EINVAL; 751 break; 752 } 753 754 /* Only BR/EDR modes are supported here */ 755 switch (opts.mode) { 756 case L2CAP_MODE_BASIC: 757 clear_bit(CONF_STATE2_DEVICE, &chan->conf_state); 758 break; 759 case L2CAP_MODE_ERTM: 760 case L2CAP_MODE_STREAMING: 761 if (!disable_ertm) 762 break; 763 fallthrough; 764 default: 765 err = -EINVAL; 766 break; 767 } 768 769 if (err < 0) 770 break; 771 772 chan->mode = opts.mode; 773 774 BT_DBG("mode 0x%2.2x", chan->mode); 775 776 chan->imtu = opts.imtu; 777 chan->omtu = opts.omtu; 778 chan->fcs = opts.fcs; 779 chan->max_tx = opts.max_tx; 780 chan->tx_win = opts.txwin_size; 781 chan->flush_to = opts.flush_to; 782 break; 783 784 case L2CAP_LM: 785 if (copy_from_sockptr(&opt, optval, sizeof(u32))) { 786 err = -EFAULT; 787 break; 788 } 789 790 if (opt & L2CAP_LM_FIPS) { 791 err = -EINVAL; 792 break; 793 } 794 795 if (opt & L2CAP_LM_AUTH) 796 chan->sec_level = BT_SECURITY_LOW; 797 if (opt & L2CAP_LM_ENCRYPT) 798 chan->sec_level = BT_SECURITY_MEDIUM; 799 if (opt & L2CAP_LM_SECURE) 800 chan->sec_level = BT_SECURITY_HIGH; 801 802 if (opt & L2CAP_LM_MASTER) 803 set_bit(FLAG_ROLE_SWITCH, &chan->flags); 804 else 805 clear_bit(FLAG_ROLE_SWITCH, &chan->flags); 806 807 if (opt & L2CAP_LM_RELIABLE) 808 set_bit(FLAG_FORCE_RELIABLE, &chan->flags); 809 else 810 clear_bit(FLAG_FORCE_RELIABLE, &chan->flags); 811 break; 812 813 default: 814 err = -ENOPROTOOPT; 815 break; 816 } 817 818 release_sock(sk); 819 return err; 820 } 821 822 static int l2cap_set_mode(struct l2cap_chan *chan, u8 mode) 823 { 824 switch (mode) { 825 case BT_MODE_BASIC: 826 if (bdaddr_type_is_le(chan->src_type)) 827 return -EINVAL; 828 mode = L2CAP_MODE_BASIC; 829 clear_bit(CONF_STATE2_DEVICE, &chan->conf_state); 830 break; 831 case BT_MODE_ERTM: 832 if (!disable_ertm || bdaddr_type_is_le(chan->src_type)) 833 return -EINVAL; 834 mode = L2CAP_MODE_ERTM; 835 break; 836 case BT_MODE_STREAMING: 837 if (!disable_ertm || bdaddr_type_is_le(chan->src_type)) 838 return -EINVAL; 839 mode = L2CAP_MODE_STREAMING; 840 break; 841 case BT_MODE_LE_FLOWCTL: 842 if (!bdaddr_type_is_le(chan->src_type)) 843 return -EINVAL; 844 mode = L2CAP_MODE_LE_FLOWCTL; 845 break; 846 case BT_MODE_EXT_FLOWCTL: 847 /* TODO: Add support for ECRED PDUs to BR/EDR */ 848 if (!bdaddr_type_is_le(chan->src_type)) 849 return -EINVAL; 850 mode = L2CAP_MODE_EXT_FLOWCTL; 851 break; 852 default: 853 return -EINVAL; 854 } 855 856 chan->mode = mode; 857 858 return 0; 859 } 860 861 static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, 862 sockptr_t optval, unsigned int optlen) 863 { 864 struct sock *sk = sock->sk; 865 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 866 struct bt_security sec; 867 struct bt_power pwr; 868 struct l2cap_conn *conn; 869 int len, err = 0; 870 u32 opt; 871 872 BT_DBG("sk %p", sk); 873 874 if (level == SOL_L2CAP) 875 return l2cap_sock_setsockopt_old(sock, optname, optval, optlen); 876 877 if (level != SOL_BLUETOOTH) 878 return -ENOPROTOOPT; 879 880 lock_sock(sk); 881 882 switch (optname) { 883 case BT_SECURITY: 884 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED && 885 chan->chan_type != L2CAP_CHAN_FIXED && 886 chan->chan_type != L2CAP_CHAN_RAW) { 887 err = -EINVAL; 888 break; 889 } 890 891 sec.level = BT_SECURITY_LOW; 892 893 len = min_t(unsigned int, sizeof(sec), optlen); 894 if (copy_from_sockptr(&sec, optval, len)) { 895 err = -EFAULT; 896 break; 897 } 898 899 if (sec.level < BT_SECURITY_LOW || 900 sec.level > BT_SECURITY_FIPS) { 901 err = -EINVAL; 902 break; 903 } 904 905 chan->sec_level = sec.level; 906 907 if (!chan->conn) 908 break; 909 910 conn = chan->conn; 911 912 /* change security for LE channels */ 913 if (chan->scid == L2CAP_CID_ATT) { 914 if (smp_conn_security(conn->hcon, sec.level)) { 915 err = -EINVAL; 916 break; 917 } 918 919 set_bit(FLAG_PENDING_SECURITY, &chan->flags); 920 sk->sk_state = BT_CONFIG; 921 chan->state = BT_CONFIG; 922 923 /* or for ACL link */ 924 } else if ((sk->sk_state == BT_CONNECT2 && 925 test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) || 926 sk->sk_state == BT_CONNECTED) { 927 if (!l2cap_chan_check_security(chan, true)) 928 set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags); 929 else 930 sk->sk_state_change(sk); 931 } else { 932 err = -EINVAL; 933 } 934 break; 935 936 case BT_DEFER_SETUP: 937 if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) { 938 err = -EINVAL; 939 break; 940 } 941 942 if (copy_from_sockptr(&opt, optval, sizeof(u32))) { 943 err = -EFAULT; 944 break; 945 } 946 947 if (opt) { 948 set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags); 949 set_bit(FLAG_DEFER_SETUP, &chan->flags); 950 } else { 951 clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags); 952 clear_bit(FLAG_DEFER_SETUP, &chan->flags); 953 } 954 break; 955 956 case BT_FLUSHABLE: 957 if (copy_from_sockptr(&opt, optval, sizeof(u32))) { 958 err = -EFAULT; 959 break; 960 } 961 962 if (opt > BT_FLUSHABLE_ON) { 963 err = -EINVAL; 964 break; 965 } 966 967 if (opt == BT_FLUSHABLE_OFF) { 968 conn = chan->conn; 969 /* proceed further only when we have l2cap_conn and 970 No Flush support in the LM */ 971 if (!conn || !lmp_no_flush_capable(conn->hcon->hdev)) { 972 err = -EINVAL; 973 break; 974 } 975 } 976 977 if (opt) 978 set_bit(FLAG_FLUSHABLE, &chan->flags); 979 else 980 clear_bit(FLAG_FLUSHABLE, &chan->flags); 981 break; 982 983 case BT_POWER: 984 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED && 985 chan->chan_type != L2CAP_CHAN_RAW) { 986 err = -EINVAL; 987 break; 988 } 989 990 pwr.force_active = BT_POWER_FORCE_ACTIVE_ON; 991 992 len = min_t(unsigned int, sizeof(pwr), optlen); 993 if (copy_from_sockptr(&pwr, optval, len)) { 994 err = -EFAULT; 995 break; 996 } 997 998 if (pwr.force_active) 999 set_bit(FLAG_FORCE_ACTIVE, &chan->flags); 1000 else 1001 clear_bit(FLAG_FORCE_ACTIVE, &chan->flags); 1002 break; 1003 1004 case BT_CHANNEL_POLICY: 1005 if (copy_from_sockptr(&opt, optval, sizeof(u32))) { 1006 err = -EFAULT; 1007 break; 1008 } 1009 1010 if (opt > BT_CHANNEL_POLICY_AMP_PREFERRED) { 1011 err = -EINVAL; 1012 break; 1013 } 1014 1015 if (chan->mode != L2CAP_MODE_ERTM && 1016 chan->mode != L2CAP_MODE_STREAMING) { 1017 err = -EOPNOTSUPP; 1018 break; 1019 } 1020 1021 chan->chan_policy = (u8) opt; 1022 1023 if (sk->sk_state == BT_CONNECTED && 1024 chan->move_role == L2CAP_MOVE_ROLE_NONE) 1025 l2cap_move_start(chan); 1026 1027 break; 1028 1029 case BT_SNDMTU: 1030 if (!bdaddr_type_is_le(chan->src_type)) { 1031 err = -EINVAL; 1032 break; 1033 } 1034 1035 /* Setting is not supported as it's the remote side that 1036 * decides this. 1037 */ 1038 err = -EPERM; 1039 break; 1040 1041 case BT_RCVMTU: 1042 if (!bdaddr_type_is_le(chan->src_type)) { 1043 err = -EINVAL; 1044 break; 1045 } 1046 1047 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && 1048 sk->sk_state == BT_CONNECTED) { 1049 err = -EISCONN; 1050 break; 1051 } 1052 1053 if (copy_from_sockptr(&opt, optval, sizeof(u16))) { 1054 err = -EFAULT; 1055 break; 1056 } 1057 1058 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL && 1059 sk->sk_state == BT_CONNECTED) 1060 err = l2cap_chan_reconfigure(chan, opt); 1061 else 1062 chan->imtu = opt; 1063 1064 break; 1065 1066 case BT_MODE: 1067 if (!enable_ecred) { 1068 err = -ENOPROTOOPT; 1069 break; 1070 } 1071 1072 BT_DBG("sk->sk_state %u", sk->sk_state); 1073 1074 if (sk->sk_state != BT_BOUND) { 1075 err = -EINVAL; 1076 break; 1077 } 1078 1079 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { 1080 err = -EINVAL; 1081 break; 1082 } 1083 1084 if (copy_from_sockptr(&opt, optval, sizeof(u8))) { 1085 err = -EFAULT; 1086 break; 1087 } 1088 1089 BT_DBG("opt %u", opt); 1090 1091 err = l2cap_set_mode(chan, opt); 1092 if (err) 1093 break; 1094 1095 BT_DBG("mode 0x%2.2x", chan->mode); 1096 1097 break; 1098 1099 default: 1100 err = -ENOPROTOOPT; 1101 break; 1102 } 1103 1104 release_sock(sk); 1105 return err; 1106 } 1107 1108 static int l2cap_sock_sendmsg(struct socket *sock, struct msghdr *msg, 1109 size_t len) 1110 { 1111 struct sock *sk = sock->sk; 1112 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 1113 int err; 1114 1115 BT_DBG("sock %p, sk %p", sock, sk); 1116 1117 err = sock_error(sk); 1118 if (err) 1119 return err; 1120 1121 if (msg->msg_flags & MSG_OOB) 1122 return -EOPNOTSUPP; 1123 1124 if (sk->sk_state != BT_CONNECTED) 1125 return -ENOTCONN; 1126 1127 lock_sock(sk); 1128 err = bt_sock_wait_ready(sk, msg->msg_flags); 1129 release_sock(sk); 1130 if (err) 1131 return err; 1132 1133 l2cap_chan_lock(chan); 1134 err = l2cap_chan_send(chan, msg, len); 1135 l2cap_chan_unlock(chan); 1136 1137 return err; 1138 } 1139 1140 static int l2cap_sock_recvmsg(struct socket *sock, struct msghdr *msg, 1141 size_t len, int flags) 1142 { 1143 struct sock *sk = sock->sk; 1144 struct l2cap_pinfo *pi = l2cap_pi(sk); 1145 int err; 1146 1147 lock_sock(sk); 1148 1149 if (sk->sk_state == BT_CONNECT2 && test_bit(BT_SK_DEFER_SETUP, 1150 &bt_sk(sk)->flags)) { 1151 if (pi->chan->mode == L2CAP_MODE_EXT_FLOWCTL) { 1152 sk->sk_state = BT_CONNECTED; 1153 pi->chan->state = BT_CONNECTED; 1154 __l2cap_ecred_conn_rsp_defer(pi->chan); 1155 } else if (bdaddr_type_is_le(pi->chan->src_type)) { 1156 sk->sk_state = BT_CONNECTED; 1157 pi->chan->state = BT_CONNECTED; 1158 __l2cap_le_connect_rsp_defer(pi->chan); 1159 } else { 1160 sk->sk_state = BT_CONFIG; 1161 pi->chan->state = BT_CONFIG; 1162 __l2cap_connect_rsp_defer(pi->chan); 1163 } 1164 1165 err = 0; 1166 goto done; 1167 } 1168 1169 release_sock(sk); 1170 1171 if (sock->type == SOCK_STREAM) 1172 err = bt_sock_stream_recvmsg(sock, msg, len, flags); 1173 else 1174 err = bt_sock_recvmsg(sock, msg, len, flags); 1175 1176 if (pi->chan->mode != L2CAP_MODE_ERTM) 1177 return err; 1178 1179 /* Attempt to put pending rx data in the socket buffer */ 1180 1181 lock_sock(sk); 1182 1183 if (!test_bit(CONN_LOCAL_BUSY, &pi->chan->conn_state)) 1184 goto done; 1185 1186 if (pi->rx_busy_skb) { 1187 if (!__sock_queue_rcv_skb(sk, pi->rx_busy_skb)) 1188 pi->rx_busy_skb = NULL; 1189 else 1190 goto done; 1191 } 1192 1193 /* Restore data flow when half of the receive buffer is 1194 * available. This avoids resending large numbers of 1195 * frames. 1196 */ 1197 if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf >> 1) 1198 l2cap_chan_busy(pi->chan, 0); 1199 1200 done: 1201 release_sock(sk); 1202 return err; 1203 } 1204 1205 /* Kill socket (only if zapped and orphan) 1206 * Must be called on unlocked socket, with l2cap channel lock. 1207 */ 1208 static void l2cap_sock_kill(struct sock *sk) 1209 { 1210 if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket) 1211 return; 1212 1213 BT_DBG("sk %p state %s", sk, state_to_string(sk->sk_state)); 1214 1215 /* Kill poor orphan */ 1216 1217 l2cap_chan_put(l2cap_pi(sk)->chan); 1218 sock_set_flag(sk, SOCK_DEAD); 1219 sock_put(sk); 1220 } 1221 1222 static int __l2cap_wait_ack(struct sock *sk, struct l2cap_chan *chan) 1223 { 1224 DECLARE_WAITQUEUE(wait, current); 1225 int err = 0; 1226 int timeo = L2CAP_WAIT_ACK_POLL_PERIOD; 1227 /* Timeout to prevent infinite loop */ 1228 unsigned long timeout = jiffies + L2CAP_WAIT_ACK_TIMEOUT; 1229 1230 add_wait_queue(sk_sleep(sk), &wait); 1231 set_current_state(TASK_INTERRUPTIBLE); 1232 do { 1233 BT_DBG("Waiting for %d ACKs, timeout %04d ms", 1234 chan->unacked_frames, time_after(jiffies, timeout) ? 0 : 1235 jiffies_to_msecs(timeout - jiffies)); 1236 1237 if (!timeo) 1238 timeo = L2CAP_WAIT_ACK_POLL_PERIOD; 1239 1240 if (signal_pending(current)) { 1241 err = sock_intr_errno(timeo); 1242 break; 1243 } 1244 1245 release_sock(sk); 1246 timeo = schedule_timeout(timeo); 1247 lock_sock(sk); 1248 set_current_state(TASK_INTERRUPTIBLE); 1249 1250 err = sock_error(sk); 1251 if (err) 1252 break; 1253 1254 if (time_after(jiffies, timeout)) { 1255 err = -ENOLINK; 1256 break; 1257 } 1258 1259 } while (chan->unacked_frames > 0 && 1260 chan->state == BT_CONNECTED); 1261 1262 set_current_state(TASK_RUNNING); 1263 remove_wait_queue(sk_sleep(sk), &wait); 1264 return err; 1265 } 1266 1267 static int l2cap_sock_shutdown(struct socket *sock, int how) 1268 { 1269 struct sock *sk = sock->sk; 1270 struct l2cap_chan *chan; 1271 struct l2cap_conn *conn; 1272 int err = 0; 1273 1274 BT_DBG("sock %p, sk %p, how %d", sock, sk, how); 1275 1276 /* 'how' parameter is mapped to sk_shutdown as follows: 1277 * SHUT_RD (0) --> RCV_SHUTDOWN (1) 1278 * SHUT_WR (1) --> SEND_SHUTDOWN (2) 1279 * SHUT_RDWR (2) --> SHUTDOWN_MASK (3) 1280 */ 1281 how++; 1282 1283 if (!sk) 1284 return 0; 1285 1286 lock_sock(sk); 1287 1288 if ((sk->sk_shutdown & how) == how) 1289 goto shutdown_already; 1290 1291 BT_DBG("Handling sock shutdown"); 1292 1293 /* prevent sk structure from being freed whilst unlocked */ 1294 sock_hold(sk); 1295 1296 chan = l2cap_pi(sk)->chan; 1297 /* prevent chan structure from being freed whilst unlocked */ 1298 l2cap_chan_hold(chan); 1299 1300 BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); 1301 1302 if (chan->mode == L2CAP_MODE_ERTM && 1303 chan->unacked_frames > 0 && 1304 chan->state == BT_CONNECTED) { 1305 err = __l2cap_wait_ack(sk, chan); 1306 1307 /* After waiting for ACKs, check whether shutdown 1308 * has already been actioned to close the L2CAP 1309 * link such as by l2cap_disconnection_req(). 1310 */ 1311 if ((sk->sk_shutdown & how) == how) 1312 goto shutdown_matched; 1313 } 1314 1315 /* Try setting the RCV_SHUTDOWN bit, return early if SEND_SHUTDOWN 1316 * is already set 1317 */ 1318 if ((how & RCV_SHUTDOWN) && !(sk->sk_shutdown & RCV_SHUTDOWN)) { 1319 sk->sk_shutdown |= RCV_SHUTDOWN; 1320 if ((sk->sk_shutdown & how) == how) 1321 goto shutdown_matched; 1322 } 1323 1324 sk->sk_shutdown |= SEND_SHUTDOWN; 1325 release_sock(sk); 1326 1327 l2cap_chan_lock(chan); 1328 conn = chan->conn; 1329 if (conn) 1330 /* prevent conn structure from being freed */ 1331 l2cap_conn_get(conn); 1332 l2cap_chan_unlock(chan); 1333 1334 if (conn) 1335 /* mutex lock must be taken before l2cap_chan_lock() */ 1336 mutex_lock(&conn->chan_lock); 1337 1338 l2cap_chan_lock(chan); 1339 l2cap_chan_close(chan, 0); 1340 l2cap_chan_unlock(chan); 1341 1342 if (conn) { 1343 mutex_unlock(&conn->chan_lock); 1344 l2cap_conn_put(conn); 1345 } 1346 1347 lock_sock(sk); 1348 1349 if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime && 1350 !(current->flags & PF_EXITING)) 1351 err = bt_sock_wait_state(sk, BT_CLOSED, 1352 sk->sk_lingertime); 1353 1354 shutdown_matched: 1355 l2cap_chan_put(chan); 1356 sock_put(sk); 1357 1358 shutdown_already: 1359 if (!err && sk->sk_err) 1360 err = -sk->sk_err; 1361 1362 release_sock(sk); 1363 1364 BT_DBG("Sock shutdown complete err: %d", err); 1365 1366 return err; 1367 } 1368 1369 static int l2cap_sock_release(struct socket *sock) 1370 { 1371 struct sock *sk = sock->sk; 1372 int err; 1373 struct l2cap_chan *chan; 1374 1375 BT_DBG("sock %p, sk %p", sock, sk); 1376 1377 if (!sk) 1378 return 0; 1379 1380 bt_sock_unlink(&l2cap_sk_list, sk); 1381 1382 err = l2cap_sock_shutdown(sock, SHUT_RDWR); 1383 chan = l2cap_pi(sk)->chan; 1384 1385 l2cap_chan_hold(chan); 1386 l2cap_chan_lock(chan); 1387 1388 sock_orphan(sk); 1389 l2cap_sock_kill(sk); 1390 1391 l2cap_chan_unlock(chan); 1392 l2cap_chan_put(chan); 1393 1394 return err; 1395 } 1396 1397 static void l2cap_sock_cleanup_listen(struct sock *parent) 1398 { 1399 struct sock *sk; 1400 1401 BT_DBG("parent %p state %s", parent, 1402 state_to_string(parent->sk_state)); 1403 1404 /* Close not yet accepted channels */ 1405 while ((sk = bt_accept_dequeue(parent, NULL))) { 1406 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 1407 1408 BT_DBG("child chan %p state %s", chan, 1409 state_to_string(chan->state)); 1410 1411 l2cap_chan_hold(chan); 1412 l2cap_chan_lock(chan); 1413 1414 __clear_chan_timer(chan); 1415 l2cap_chan_close(chan, ECONNRESET); 1416 l2cap_sock_kill(sk); 1417 1418 l2cap_chan_unlock(chan); 1419 l2cap_chan_put(chan); 1420 } 1421 } 1422 1423 static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan) 1424 { 1425 struct sock *sk, *parent = chan->data; 1426 1427 lock_sock(parent); 1428 1429 /* Check for backlog size */ 1430 if (sk_acceptq_is_full(parent)) { 1431 BT_DBG("backlog full %d", parent->sk_ack_backlog); 1432 release_sock(parent); 1433 return NULL; 1434 } 1435 1436 sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP, 1437 GFP_ATOMIC, 0); 1438 if (!sk) { 1439 release_sock(parent); 1440 return NULL; 1441 } 1442 1443 bt_sock_reclassify_lock(sk, BTPROTO_L2CAP); 1444 1445 l2cap_sock_init(sk, parent); 1446 1447 bt_accept_enqueue(parent, sk, false); 1448 1449 release_sock(parent); 1450 1451 return l2cap_pi(sk)->chan; 1452 } 1453 1454 static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) 1455 { 1456 struct sock *sk = chan->data; 1457 int err; 1458 1459 lock_sock(sk); 1460 1461 if (l2cap_pi(sk)->rx_busy_skb) { 1462 err = -ENOMEM; 1463 goto done; 1464 } 1465 1466 if (chan->mode != L2CAP_MODE_ERTM && 1467 chan->mode != L2CAP_MODE_STREAMING) { 1468 /* Even if no filter is attached, we could potentially 1469 * get errors from security modules, etc. 1470 */ 1471 err = sk_filter(sk, skb); 1472 if (err) 1473 goto done; 1474 } 1475 1476 err = __sock_queue_rcv_skb(sk, skb); 1477 1478 /* For ERTM, handle one skb that doesn't fit into the recv 1479 * buffer. This is important to do because the data frames 1480 * have already been acked, so the skb cannot be discarded. 1481 * 1482 * Notify the l2cap core that the buffer is full, so the 1483 * LOCAL_BUSY state is entered and no more frames are 1484 * acked and reassembled until there is buffer space 1485 * available. 1486 */ 1487 if (err < 0 && chan->mode == L2CAP_MODE_ERTM) { 1488 l2cap_pi(sk)->rx_busy_skb = skb; 1489 l2cap_chan_busy(chan, 1); 1490 err = 0; 1491 } 1492 1493 done: 1494 release_sock(sk); 1495 1496 return err; 1497 } 1498 1499 static void l2cap_sock_close_cb(struct l2cap_chan *chan) 1500 { 1501 struct sock *sk = chan->data; 1502 1503 l2cap_sock_kill(sk); 1504 } 1505 1506 static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err) 1507 { 1508 struct sock *sk = chan->data; 1509 struct sock *parent; 1510 1511 BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); 1512 1513 /* This callback can be called both for server (BT_LISTEN) 1514 * sockets as well as "normal" ones. To avoid lockdep warnings 1515 * with child socket locking (through l2cap_sock_cleanup_listen) 1516 * we need separation into separate nesting levels. The simplest 1517 * way to accomplish this is to inherit the nesting level used 1518 * for the channel. 1519 */ 1520 lock_sock_nested(sk, atomic_read(&chan->nesting)); 1521 1522 parent = bt_sk(sk)->parent; 1523 1524 switch (chan->state) { 1525 case BT_OPEN: 1526 case BT_BOUND: 1527 case BT_CLOSED: 1528 break; 1529 case BT_LISTEN: 1530 l2cap_sock_cleanup_listen(sk); 1531 sk->sk_state = BT_CLOSED; 1532 chan->state = BT_CLOSED; 1533 1534 break; 1535 default: 1536 sk->sk_state = BT_CLOSED; 1537 chan->state = BT_CLOSED; 1538 1539 sk->sk_err = err; 1540 1541 if (parent) { 1542 bt_accept_unlink(sk); 1543 parent->sk_data_ready(parent); 1544 } else { 1545 sk->sk_state_change(sk); 1546 } 1547 1548 break; 1549 } 1550 release_sock(sk); 1551 1552 /* Only zap after cleanup to avoid use after free race */ 1553 sock_set_flag(sk, SOCK_ZAPPED); 1554 1555 } 1556 1557 static void l2cap_sock_state_change_cb(struct l2cap_chan *chan, int state, 1558 int err) 1559 { 1560 struct sock *sk = chan->data; 1561 1562 sk->sk_state = state; 1563 1564 if (err) 1565 sk->sk_err = err; 1566 } 1567 1568 static struct sk_buff *l2cap_sock_alloc_skb_cb(struct l2cap_chan *chan, 1569 unsigned long hdr_len, 1570 unsigned long len, int nb) 1571 { 1572 struct sock *sk = chan->data; 1573 struct sk_buff *skb; 1574 int err; 1575 1576 l2cap_chan_unlock(chan); 1577 skb = bt_skb_send_alloc(sk, hdr_len + len, nb, &err); 1578 l2cap_chan_lock(chan); 1579 1580 if (!skb) 1581 return ERR_PTR(err); 1582 1583 skb->priority = sk->sk_priority; 1584 1585 bt_cb(skb)->l2cap.chan = chan; 1586 1587 return skb; 1588 } 1589 1590 static void l2cap_sock_ready_cb(struct l2cap_chan *chan) 1591 { 1592 struct sock *sk = chan->data; 1593 struct sock *parent; 1594 1595 lock_sock(sk); 1596 1597 parent = bt_sk(sk)->parent; 1598 1599 BT_DBG("sk %p, parent %p", sk, parent); 1600 1601 sk->sk_state = BT_CONNECTED; 1602 sk->sk_state_change(sk); 1603 1604 if (parent) 1605 parent->sk_data_ready(parent); 1606 1607 release_sock(sk); 1608 } 1609 1610 static void l2cap_sock_defer_cb(struct l2cap_chan *chan) 1611 { 1612 struct sock *parent, *sk = chan->data; 1613 1614 lock_sock(sk); 1615 1616 parent = bt_sk(sk)->parent; 1617 if (parent) 1618 parent->sk_data_ready(parent); 1619 1620 release_sock(sk); 1621 } 1622 1623 static void l2cap_sock_resume_cb(struct l2cap_chan *chan) 1624 { 1625 struct sock *sk = chan->data; 1626 1627 if (test_and_clear_bit(FLAG_PENDING_SECURITY, &chan->flags)) { 1628 sk->sk_state = BT_CONNECTED; 1629 chan->state = BT_CONNECTED; 1630 } 1631 1632 clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags); 1633 sk->sk_state_change(sk); 1634 } 1635 1636 static void l2cap_sock_set_shutdown_cb(struct l2cap_chan *chan) 1637 { 1638 struct sock *sk = chan->data; 1639 1640 lock_sock(sk); 1641 sk->sk_shutdown = SHUTDOWN_MASK; 1642 release_sock(sk); 1643 } 1644 1645 static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan) 1646 { 1647 struct sock *sk = chan->data; 1648 1649 return sk->sk_sndtimeo; 1650 } 1651 1652 static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan) 1653 { 1654 struct sock *sk = chan->data; 1655 1656 return sk->sk_peer_pid; 1657 } 1658 1659 static void l2cap_sock_suspend_cb(struct l2cap_chan *chan) 1660 { 1661 struct sock *sk = chan->data; 1662 1663 set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags); 1664 sk->sk_state_change(sk); 1665 } 1666 1667 static int l2cap_sock_filter(struct l2cap_chan *chan, struct sk_buff *skb) 1668 { 1669 struct sock *sk = chan->data; 1670 1671 switch (chan->mode) { 1672 case L2CAP_MODE_ERTM: 1673 case L2CAP_MODE_STREAMING: 1674 return sk_filter(sk, skb); 1675 } 1676 1677 return 0; 1678 } 1679 1680 static const struct l2cap_ops l2cap_chan_ops = { 1681 .name = "L2CAP Socket Interface", 1682 .new_connection = l2cap_sock_new_connection_cb, 1683 .recv = l2cap_sock_recv_cb, 1684 .close = l2cap_sock_close_cb, 1685 .teardown = l2cap_sock_teardown_cb, 1686 .state_change = l2cap_sock_state_change_cb, 1687 .ready = l2cap_sock_ready_cb, 1688 .defer = l2cap_sock_defer_cb, 1689 .resume = l2cap_sock_resume_cb, 1690 .suspend = l2cap_sock_suspend_cb, 1691 .set_shutdown = l2cap_sock_set_shutdown_cb, 1692 .get_sndtimeo = l2cap_sock_get_sndtimeo_cb, 1693 .get_peer_pid = l2cap_sock_get_peer_pid_cb, 1694 .alloc_skb = l2cap_sock_alloc_skb_cb, 1695 .filter = l2cap_sock_filter, 1696 }; 1697 1698 static void l2cap_sock_destruct(struct sock *sk) 1699 { 1700 BT_DBG("sk %p", sk); 1701 1702 if (l2cap_pi(sk)->chan) 1703 l2cap_chan_put(l2cap_pi(sk)->chan); 1704 1705 if (l2cap_pi(sk)->rx_busy_skb) { 1706 kfree_skb(l2cap_pi(sk)->rx_busy_skb); 1707 l2cap_pi(sk)->rx_busy_skb = NULL; 1708 } 1709 1710 skb_queue_purge(&sk->sk_receive_queue); 1711 skb_queue_purge(&sk->sk_write_queue); 1712 } 1713 1714 static void l2cap_skb_msg_name(struct sk_buff *skb, void *msg_name, 1715 int *msg_namelen) 1716 { 1717 DECLARE_SOCKADDR(struct sockaddr_l2 *, la, msg_name); 1718 1719 memset(la, 0, sizeof(struct sockaddr_l2)); 1720 la->l2_family = AF_BLUETOOTH; 1721 la->l2_psm = bt_cb(skb)->l2cap.psm; 1722 bacpy(&la->l2_bdaddr, &bt_cb(skb)->l2cap.bdaddr); 1723 1724 *msg_namelen = sizeof(struct sockaddr_l2); 1725 } 1726 1727 static void l2cap_sock_init(struct sock *sk, struct sock *parent) 1728 { 1729 struct l2cap_chan *chan = l2cap_pi(sk)->chan; 1730 1731 BT_DBG("sk %p", sk); 1732 1733 if (parent) { 1734 struct l2cap_chan *pchan = l2cap_pi(parent)->chan; 1735 1736 sk->sk_type = parent->sk_type; 1737 bt_sk(sk)->flags = bt_sk(parent)->flags; 1738 1739 chan->chan_type = pchan->chan_type; 1740 chan->imtu = pchan->imtu; 1741 chan->omtu = pchan->omtu; 1742 chan->conf_state = pchan->conf_state; 1743 chan->mode = pchan->mode; 1744 chan->fcs = pchan->fcs; 1745 chan->max_tx = pchan->max_tx; 1746 chan->tx_win = pchan->tx_win; 1747 chan->tx_win_max = pchan->tx_win_max; 1748 chan->sec_level = pchan->sec_level; 1749 chan->flags = pchan->flags; 1750 chan->tx_credits = pchan->tx_credits; 1751 chan->rx_credits = pchan->rx_credits; 1752 1753 if (chan->chan_type == L2CAP_CHAN_FIXED) { 1754 chan->scid = pchan->scid; 1755 chan->dcid = pchan->scid; 1756 } 1757 1758 security_sk_clone(parent, sk); 1759 } else { 1760 switch (sk->sk_type) { 1761 case SOCK_RAW: 1762 chan->chan_type = L2CAP_CHAN_RAW; 1763 break; 1764 case SOCK_DGRAM: 1765 chan->chan_type = L2CAP_CHAN_CONN_LESS; 1766 bt_sk(sk)->skb_msg_name = l2cap_skb_msg_name; 1767 break; 1768 case SOCK_SEQPACKET: 1769 case SOCK_STREAM: 1770 chan->chan_type = L2CAP_CHAN_CONN_ORIENTED; 1771 break; 1772 } 1773 1774 chan->imtu = L2CAP_DEFAULT_MTU; 1775 chan->omtu = 0; 1776 if (!disable_ertm && sk->sk_type == SOCK_STREAM) { 1777 chan->mode = L2CAP_MODE_ERTM; 1778 set_bit(CONF_STATE2_DEVICE, &chan->conf_state); 1779 } else { 1780 chan->mode = L2CAP_MODE_BASIC; 1781 } 1782 1783 l2cap_chan_set_defaults(chan); 1784 } 1785 1786 /* Default config options */ 1787 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO; 1788 1789 chan->data = sk; 1790 chan->ops = &l2cap_chan_ops; 1791 } 1792 1793 static struct proto l2cap_proto = { 1794 .name = "L2CAP", 1795 .owner = THIS_MODULE, 1796 .obj_size = sizeof(struct l2cap_pinfo) 1797 }; 1798 1799 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, 1800 int proto, gfp_t prio, int kern) 1801 { 1802 struct sock *sk; 1803 struct l2cap_chan *chan; 1804 1805 sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto, kern); 1806 if (!sk) 1807 return NULL; 1808 1809 sock_init_data(sock, sk); 1810 INIT_LIST_HEAD(&bt_sk(sk)->accept_q); 1811 1812 sk->sk_destruct = l2cap_sock_destruct; 1813 sk->sk_sndtimeo = L2CAP_CONN_TIMEOUT; 1814 1815 sock_reset_flag(sk, SOCK_ZAPPED); 1816 1817 sk->sk_protocol = proto; 1818 sk->sk_state = BT_OPEN; 1819 1820 chan = l2cap_chan_create(); 1821 if (!chan) { 1822 sk_free(sk); 1823 return NULL; 1824 } 1825 1826 l2cap_chan_hold(chan); 1827 1828 l2cap_pi(sk)->chan = chan; 1829 1830 return sk; 1831 } 1832 1833 static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol, 1834 int kern) 1835 { 1836 struct sock *sk; 1837 1838 BT_DBG("sock %p", sock); 1839 1840 sock->state = SS_UNCONNECTED; 1841 1842 if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM && 1843 sock->type != SOCK_DGRAM && sock->type != SOCK_RAW) 1844 return -ESOCKTNOSUPPORT; 1845 1846 if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW)) 1847 return -EPERM; 1848 1849 sock->ops = &l2cap_sock_ops; 1850 1851 sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern); 1852 if (!sk) 1853 return -ENOMEM; 1854 1855 l2cap_sock_init(sk, NULL); 1856 bt_sock_link(&l2cap_sk_list, sk); 1857 return 0; 1858 } 1859 1860 static const struct proto_ops l2cap_sock_ops = { 1861 .family = PF_BLUETOOTH, 1862 .owner = THIS_MODULE, 1863 .release = l2cap_sock_release, 1864 .bind = l2cap_sock_bind, 1865 .connect = l2cap_sock_connect, 1866 .listen = l2cap_sock_listen, 1867 .accept = l2cap_sock_accept, 1868 .getname = l2cap_sock_getname, 1869 .sendmsg = l2cap_sock_sendmsg, 1870 .recvmsg = l2cap_sock_recvmsg, 1871 .poll = bt_sock_poll, 1872 .ioctl = bt_sock_ioctl, 1873 .gettstamp = sock_gettstamp, 1874 .mmap = sock_no_mmap, 1875 .socketpair = sock_no_socketpair, 1876 .shutdown = l2cap_sock_shutdown, 1877 .setsockopt = l2cap_sock_setsockopt, 1878 .getsockopt = l2cap_sock_getsockopt 1879 }; 1880 1881 static const struct net_proto_family l2cap_sock_family_ops = { 1882 .family = PF_BLUETOOTH, 1883 .owner = THIS_MODULE, 1884 .create = l2cap_sock_create, 1885 }; 1886 1887 int __init l2cap_init_sockets(void) 1888 { 1889 int err; 1890 1891 BUILD_BUG_ON(sizeof(struct sockaddr_l2) > sizeof(struct sockaddr)); 1892 1893 err = proto_register(&l2cap_proto, 0); 1894 if (err < 0) 1895 return err; 1896 1897 err = bt_sock_register(BTPROTO_L2CAP, &l2cap_sock_family_ops); 1898 if (err < 0) { 1899 BT_ERR("L2CAP socket registration failed"); 1900 goto error; 1901 } 1902 1903 err = bt_procfs_init(&init_net, "l2cap", &l2cap_sk_list, 1904 NULL); 1905 if (err < 0) { 1906 BT_ERR("Failed to create L2CAP proc file"); 1907 bt_sock_unregister(BTPROTO_L2CAP); 1908 goto error; 1909 } 1910 1911 BT_INFO("L2CAP socket layer initialized"); 1912 1913 return 0; 1914 1915 error: 1916 proto_unregister(&l2cap_proto); 1917 return err; 1918 } 1919 1920 void l2cap_cleanup_sockets(void) 1921 { 1922 bt_procfs_cleanup(&init_net, "l2cap"); 1923 bt_sock_unregister(BTPROTO_L2CAP); 1924 proto_unregister(&l2cap_proto); 1925 } 1926