net/bluetooth/rfcomm/core.c

   1 /*
   2    RFCOMM implementation for Linux Bluetooth stack (BlueZ).
   3    Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
   4    Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License version 2 as
   8    published by the Free Software Foundation;
   9
  10    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  11    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  12    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
  13    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
  14    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
  15    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18
  19    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
  20    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
  21    SOFTWARE IS DISCLAIMED.
  22 */
  23
  24 /*
  25  * Bluetooth RFCOMM core.
  26  */
  27
  28 #include <linux/module.h>
  29 #include <linux/errno.h>
  30 #include <linux/kernel.h>
  31 #include <linux/sched.h>
  32 #include <linux/signal.h>
  33 #include <linux/init.h>
  34 #include <linux/wait.h>
  35 #include <linux/device.h>
  36 #include <linux/debugfs.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/net.h>
  39 #include <linux/mutex.h>
  40 #include <linux/kthread.h>
  41 #include <linux/slab.h>
  42
  43 #include <net/sock.h>
  44 #include <linux/uaccess.h>
  45 #include <asm/unaligned.h>
  46
  47 #include <net/bluetooth/bluetooth.h>
  48 #include <net/bluetooth/hci_core.h>
  49 #include <net/bluetooth/l2cap.h>
  50 #include <net/bluetooth/rfcomm.h>
  51
  52 #define VERSION "1.11"
  53
  54 static int disable_cfc;
  55 static int l2cap_ertm;
  56 static int channel_mtu = -1;
  57 static unsigned int l2cap_mtu = RFCOMM_MAX_L2CAP_MTU;
  58
  59 static struct task_struct *rfcomm_thread;
  60
  61 static DEFINE_MUTEX(rfcomm_mutex);
  62 #define rfcomm_lock()   mutex_lock(&rfcomm_mutex)
  63 #define rfcomm_unlock() mutex_unlock(&rfcomm_mutex)
  64
  65
  66 static LIST_HEAD(session_list);
  67
  68 static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len);
  69 static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci);
  70 static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci);
  71 static int rfcomm_queue_disc(struct rfcomm_dlc *d);
  72 static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type);
  73 static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d);
  74 static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig);
  75 static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len);
  76 static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits);
  77 static void rfcomm_make_uih(struct sk_buff *skb, u8 addr);
  78
  79 static void rfcomm_process_connect(struct rfcomm_session *s);
  80
  81 static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
  82                                                         bdaddr_t *dst,
  83                                                         u8 sec_level,
  84                                                         int *err);
  85 static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst);
  86 static void rfcomm_session_del(struct rfcomm_session *s);
  87
  88 /* ---- RFCOMM frame parsing macros ---- */
  89 #define __get_dlci(b)     ((b & 0xfc) >> 2)
  90 #define __get_channel(b)  ((b & 0xf8) >> 3)
  91 #define __get_dir(b)      ((b & 0x04) >> 2)
  92 #define __get_type(b)     ((b & 0xef))
  93
  94 #define __test_ea(b)      ((b & 0x01))
  95 #define __test_cr(b)      ((b & 0x02))
  96 #define __test_pf(b)      ((b & 0x10))
  97
  98 #define __addr(cr, dlci)       (((dlci & 0x3f) << 2) | (cr << 1) | 0x01)
  99 #define __ctrl(type, pf)       (((type & 0xef) | (pf << 4)))
 100 #define __dlci(dir, chn)       (((chn & 0x1f) << 1) | dir)
 101 #define __srv_channel(dlci)    (dlci >> 1)
 102 #define __dir(dlci)            (dlci & 0x01)
 103
 104 #define __len8(len)       (((len) << 1) | 1)
 105 #define __len16(len)      ((len) << 1)
 106
 107 /* MCC macros */
 108 #define __mcc_type(cr, type)   (((type << 2) | (cr << 1) | 0x01))
 109 #define __get_mcc_type(b) ((b & 0xfc) >> 2)
 110 #define __get_mcc_len(b)  ((b & 0xfe) >> 1)
 111
 112 /* RPN macros */
 113 #define __rpn_line_settings(data, stop, parity)  ((data & 0x3) | ((stop & 0x1) << 2) | ((parity & 0x7) << 3))
 114 #define __get_rpn_data_bits(line) ((line) & 0x3)
 115 #define __get_rpn_stop_bits(line) (((line) >> 2) & 0x1)
 116 #define __get_rpn_parity(line)    (((line) >> 3) & 0x7)
 117
 118 static inline void rfcomm_schedule(void)
 119 {
 120         if (!rfcomm_thread)
 121                 return;
 122         wake_up_process(rfcomm_thread);
 123 }
 124
 125 static inline void rfcomm_session_put(struct rfcomm_session *s)
 126 {
 127         if (atomic_dec_and_test(&s->refcnt))
 128                 rfcomm_session_del(s);
 129 }
 130
 131 /* ---- RFCOMM FCS computation ---- */
 132
 133 /* reversed, 8-bit, poly=0x07 */
 134 static unsigned char rfcomm_crc_table[256] = {
 135         0x00, 0x91, 0xe3, 0x72, 0x07, 0x96, 0xe4, 0x75,
 136         0x0e, 0x9f, 0xed, 0x7c, 0x09, 0x98, 0xea, 0x7b,
 137         0x1c, 0x8d, 0xff, 0x6e, 0x1b, 0x8a, 0xf8, 0x69,
 138         0x12, 0x83, 0xf1, 0x60, 0x15, 0x84, 0xf6, 0x67,
 139
 140         0x38, 0xa9, 0xdb, 0x4a, 0x3f, 0xae, 0xdc, 0x4d,
 141         0x36, 0xa7, 0xd5, 0x44, 0x31, 0xa0, 0xd2, 0x43,
 142         0x24, 0xb5, 0xc7, 0x56, 0x23, 0xb2, 0xc0, 0x51,
 143         0x2a, 0xbb, 0xc9, 0x58, 0x2d, 0xbc, 0xce, 0x5f,
 144
 145         0x70, 0xe1, 0x93, 0x02, 0x77, 0xe6, 0x94, 0x05,
 146         0x7e, 0xef, 0x9d, 0x0c, 0x79, 0xe8, 0x9a, 0x0b,
 147         0x6c, 0xfd, 0x8f, 0x1e, 0x6b, 0xfa, 0x88, 0x19,
 148         0x62, 0xf3, 0x81, 0x10, 0x65, 0xf4, 0x86, 0x17,
 149
 150         0x48, 0xd9, 0xab, 0x3a, 0x4f, 0xde, 0xac, 0x3d,
 151         0x46, 0xd7, 0xa5, 0x34, 0x41, 0xd0, 0xa2, 0x33,
 152         0x54, 0xc5, 0xb7, 0x26, 0x53, 0xc2, 0xb0, 0x21,
 153         0x5a, 0xcb, 0xb9, 0x28, 0x5d, 0xcc, 0xbe, 0x2f,
 154
 155         0xe0, 0x71, 0x03, 0x92, 0xe7, 0x76, 0x04, 0x95,
 156         0xee, 0x7f, 0x0d, 0x9c, 0xe9, 0x78, 0x0a, 0x9b,
 157         0xfc, 0x6d, 0x1f, 0x8e, 0xfb, 0x6a, 0x18, 0x89,
 158         0xf2, 0x63, 0x11, 0x80, 0xf5, 0x64, 0x16, 0x87,
 159
 160         0xd8, 0x49, 0x3b, 0xaa, 0xdf, 0x4e, 0x3c, 0xad,
 161         0xd6, 0x47, 0x35, 0xa4, 0xd1, 0x40, 0x32, 0xa3,
 162         0xc4, 0x55, 0x27, 0xb6, 0xc3, 0x52, 0x20, 0xb1,
 163         0xca, 0x5b, 0x29, 0xb8, 0xcd, 0x5c, 0x2e, 0xbf,
 164
 165         0x90, 0x01, 0x73, 0xe2, 0x97, 0x06, 0x74, 0xe5,
 166         0x9e, 0x0f, 0x7d, 0xec, 0x99, 0x08, 0x7a, 0xeb,
 167         0x8c, 0x1d, 0x6f, 0xfe, 0x8b, 0x1a, 0x68, 0xf9,
 168         0x82, 0x13, 0x61, 0xf0, 0x85, 0x14, 0x66, 0xf7,
 169
 170         0xa8, 0x39, 0x4b, 0xda, 0xaf, 0x3e, 0x4c, 0xdd,
 171         0xa6, 0x37, 0x45, 0xd4, 0xa1, 0x30, 0x42, 0xd3,
 172         0xb4, 0x25, 0x57, 0xc6, 0xb3, 0x22, 0x50, 0xc1,
 173         0xba, 0x2b, 0x59, 0xc8, 0xbd, 0x2c, 0x5e, 0xcf
 174 };
 175
 176 /* CRC on 2 bytes */
 177 #define __crc(data) (rfcomm_crc_table[rfcomm_crc_table[0xff ^ data[0]] ^ data[1]])
 178
 179 /* FCS on 2 bytes */
 180 static inline u8 __fcs(u8 *data)
 181 {
 182         return 0xff - __crc(data);
 183 }
 184
 185 /* FCS on 3 bytes */
 186 static inline u8 __fcs2(u8 *data)
 187 {
 188         return 0xff - rfcomm_crc_table[__crc(data) ^ data[2]];
 189 }
 190
 191 /* Check FCS */
 192 static inline int __check_fcs(u8 *data, int type, u8 fcs)
 193 {
 194         u8 f = __crc(data);
 195
 196         if (type != RFCOMM_UIH)
 197                 f = rfcomm_crc_table[f ^ data[2]];
 198
 199         return rfcomm_crc_table[f ^ fcs] != 0xcf;
 200 }
 201
 202 /* ---- L2CAP callbacks ---- */
 203 static void rfcomm_l2state_change(struct sock *sk)
 204 {
 205         BT_DBG("%p state %d", sk, sk->sk_state);
 206         rfcomm_schedule();
 207 }
 208
 209 static void rfcomm_l2data_ready(struct sock *sk, int bytes)
 210 {
 211         BT_DBG("%p bytes %d", sk, bytes);
 212         rfcomm_schedule();
 213 }
 214
 215 static int rfcomm_l2sock_create(struct socket **sock)
 216 {
 217         int err;
 218
 219         BT_DBG("");
 220
 221         err = sock_create_kern(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP, sock);
 222         if (!err) {
 223                 struct sock *sk = (*sock)->sk;
 224                 sk->sk_data_ready   = rfcomm_l2data_ready;
 225                 sk->sk_state_change = rfcomm_l2state_change;
 226         }
 227         return err;
 228 }
 229
 230 static inline int rfcomm_check_security(struct rfcomm_dlc *d)
 231 {
 232         struct sock *sk = d->session->sock->sk;
 233         struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
 234
 235         __u8 auth_type;
 236
 237         switch (d->sec_level) {
 238         case BT_SECURITY_HIGH:
 239                 auth_type = HCI_AT_GENERAL_BONDING_MITM;
 240                 break;
 241         case BT_SECURITY_MEDIUM:
 242                 auth_type = HCI_AT_GENERAL_BONDING;
 243                 break;
 244         default:
 245                 auth_type = HCI_AT_NO_BONDING;
 246                 break;
 247         }
 248
 249         return hci_conn_security(conn->hcon, d->sec_level, auth_type);
 250 }
 251
 252 static void rfcomm_session_timeout(unsigned long arg)
 253 {
 254         struct rfcomm_session *s = (void *) arg;
 255
 256         BT_DBG("session %p state %ld", s, s->state);
 257
 258         set_bit(RFCOMM_TIMED_OUT, &s->flags);
 259         rfcomm_schedule();
 260 }
 261
 262 static void rfcomm_session_set_timer(struct rfcomm_session *s, long timeout)
 263 {
 264         BT_DBG("session %p state %ld timeout %ld", s, s->state, timeout);
 265
 266         if (!mod_timer(&s->timer, jiffies + timeout))
 267                 rfcomm_session_hold(s);
 268 }
 269
 270 static void rfcomm_session_clear_timer(struct rfcomm_session *s)
 271 {
 272         BT_DBG("session %p state %ld", s, s->state);
 273
 274         if (timer_pending(&s->timer) && del_timer(&s->timer))
 275                 rfcomm_session_put(s);
 276 }
 277
 278 /* ---- RFCOMM DLCs ---- */
 279 static void rfcomm_dlc_timeout(unsigned long arg)
 280 {
 281         struct rfcomm_dlc *d = (void *) arg;
 282
 283         BT_DBG("dlc %p state %ld", d, d->state);
 284
 285         set_bit(RFCOMM_TIMED_OUT, &d->flags);
 286         rfcomm_dlc_put(d);
 287         rfcomm_schedule();
 288 }
 289
 290 static void rfcomm_dlc_set_timer(struct rfcomm_dlc *d, long timeout)
 291 {
 292         BT_DBG("dlc %p state %ld timeout %ld", d, d->state, timeout);
 293
 294         if (!mod_timer(&d->timer, jiffies + timeout))
 295                 rfcomm_dlc_hold(d);
 296 }
 297
 298 static void rfcomm_dlc_clear_timer(struct rfcomm_dlc *d)
 299 {
 300         BT_DBG("dlc %p state %ld", d, d->state);
 301
 302         if (timer_pending(&d->timer) && del_timer(&d->timer))
 303                 rfcomm_dlc_put(d);
 304 }
 305
 306 static void rfcomm_dlc_clear_state(struct rfcomm_dlc *d)
 307 {
 308         BT_DBG("%p", d);
 309
 310         d->state      = BT_OPEN;
 311         d->flags      = 0;
 312         d->mscex      = 0;
 313         d->sec_level  = BT_SECURITY_LOW;
 314         d->mtu        = RFCOMM_DEFAULT_MTU;
 315         d->v24_sig    = RFCOMM_V24_RTC | RFCOMM_V24_RTR | RFCOMM_V24_DV;
 316
 317         d->cfc        = RFCOMM_CFC_DISABLED;
 318         d->rx_credits = RFCOMM_DEFAULT_CREDITS;
 319 }
 320
 321 struct rfcomm_dlc *rfcomm_dlc_alloc(gfp_t prio)
 322 {
 323         struct rfcomm_dlc *d = kzalloc(sizeof(*d), prio);
 324
 325         if (!d)
 326                 return NULL;
 327
 328         setup_timer(&d->timer, rfcomm_dlc_timeout, (unsigned long)d);
 329
 330         skb_queue_head_init(&d->tx_queue);
 331         spin_lock_init(&d->lock);
 332         atomic_set(&d->refcnt, 1);
 333
 334         rfcomm_dlc_clear_state(d);
 335
 336         BT_DBG("%p", d);
 337
 338         return d;
 339 }
 340
 341 void rfcomm_dlc_free(struct rfcomm_dlc *d)
 342 {
 343         BT_DBG("%p", d);
 344
 345         skb_queue_purge(&d->tx_queue);
 346         kfree(d);
 347 }
 348
 349 static void rfcomm_dlc_link(struct rfcomm_session *s, struct rfcomm_dlc *d)
 350 {
 351         BT_DBG("dlc %p session %p", d, s);
 352
 353         rfcomm_session_hold(s);
 354
 355         rfcomm_session_clear_timer(s);
 356         rfcomm_dlc_hold(d);
 357         list_add(&d->list, &s->dlcs);
 358         d->session = s;
 359 }
 360
 361 static void rfcomm_dlc_unlink(struct rfcomm_dlc *d)
 362 {
 363         struct rfcomm_session *s = d->session;
 364
 365         BT_DBG("dlc %p refcnt %d session %p", d, atomic_read(&d->refcnt), s);
 366
 367         list_del(&d->list);
 368         d->session = NULL;
 369         rfcomm_dlc_put(d);
 370
 371         if (list_empty(&s->dlcs))
 372                 rfcomm_session_set_timer(s, RFCOMM_IDLE_TIMEOUT);
 373
 374         rfcomm_session_put(s);
 375 }
 376
 377 static struct rfcomm_dlc *rfcomm_dlc_get(struct rfcomm_session *s, u8 dlci)
 378 {
 379         struct rfcomm_dlc *d;
 380         struct list_head *p;
 381
 382         list_for_each(p, &s->dlcs) {
 383                 d = list_entry(p, struct rfcomm_dlc, list);
 384                 if (d->dlci == dlci)
 385                         return d;
 386         }
 387         return NULL;
 388 }
 389
 390 static int __rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
 391 {
 392         struct rfcomm_session *s;
 393         int err = 0;
 394         u8 dlci;
 395
 396         BT_DBG("dlc %p state %ld %s %s channel %d",
 397                         d, d->state, batostr(src), batostr(dst), channel);
 398
 399         if (channel < 1 || channel > 30)
 400                 return -EINVAL;
 401
 402         if (d->state != BT_OPEN && d->state != BT_CLOSED)
 403                 return 0;
 404
 405         s = rfcomm_session_get(src, dst);
 406         if (!s) {
 407                 s = rfcomm_session_create(src, dst, d->sec_level, &err);
 408                 if (!s)
 409                         return err;
 410         }
 411
 412         dlci = __dlci(!s->initiator, channel);
 413
 414         /* Check if DLCI already exists */
 415         if (rfcomm_dlc_get(s, dlci))
 416                 return -EBUSY;
 417
 418         rfcomm_dlc_clear_state(d);
 419
 420         d->dlci     = dlci;
 421         d->addr     = __addr(s->initiator, dlci);
 422         d->priority = 7;
 423
 424         d->state = BT_CONFIG;
 425         rfcomm_dlc_link(s, d);
 426
 427         d->out = 1;
 428
 429         d->mtu = s->mtu;
 430         d->cfc = (s->cfc == RFCOMM_CFC_UNKNOWN) ? 0 : s->cfc;
 431
 432         if (s->state == BT_CONNECTED) {
 433                 if (rfcomm_check_security(d))
 434                         rfcomm_send_pn(s, 1, d);
 435                 else
 436                         set_bit(RFCOMM_AUTH_PENDING, &d->flags);
 437         }
 438
 439         rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
 440
 441         return 0;
 442 }
 443
 444 int rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
 445 {
 446         int r;
 447
 448         rfcomm_lock();
 449
 450         r = __rfcomm_dlc_open(d, src, dst, channel);
 451
 452         rfcomm_unlock();
 453         return r;
 454 }
 455
 456 static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
 457 {
 458         struct rfcomm_session *s = d->session;
 459         if (!s)
 460                 return 0;
 461
 462         BT_DBG("dlc %p state %ld dlci %d err %d session %p",
 463                         d, d->state, d->dlci, err, s);
 464
 465         switch (d->state) {
 466         case BT_CONNECT:
 467         case BT_CONFIG:
 468                 if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
 469                         set_bit(RFCOMM_AUTH_REJECT, &d->flags);
 470                         rfcomm_schedule();
 471                         break;
 472                 }
 473                 /* Fall through */
 474
 475         case BT_CONNECTED:
 476                 d->state = BT_DISCONN;
 477                 if (skb_queue_empty(&d->tx_queue)) {
 478                         rfcomm_send_disc(s, d->dlci);
 479                         rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT);
 480                 } else {
 481                         rfcomm_queue_disc(d);
 482                         rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT * 2);
 483                 }
 484                 break;
 485
 486         case BT_OPEN:
 487         case BT_CONNECT2:
 488                 if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
 489                         set_bit(RFCOMM_AUTH_REJECT, &d->flags);
 490                         rfcomm_schedule();
 491                         break;
 492                 }
 493                 /* Fall through */
 494
 495         default:
 496                 rfcomm_dlc_clear_timer(d);
 497
 498                 rfcomm_dlc_lock(d);
 499                 d->state = BT_CLOSED;
 500                 d->state_change(d, err);
 501                 rfcomm_dlc_unlock(d);
 502
 503                 skb_queue_purge(&d->tx_queue);
 504                 rfcomm_dlc_unlink(d);
 505         }
 506
 507         return 0;
 508 }
 509
 510 int rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
 511 {
 512         int r;
 513
 514         rfcomm_lock();
 515
 516         r = __rfcomm_dlc_close(d, err);
 517
 518         rfcomm_unlock();
 519         return r;
 520 }
 521
 522 int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
 523 {
 524         int len = skb->len;
 525
 526         if (d->state != BT_CONNECTED)
 527                 return -ENOTCONN;
 528
 529         BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
 530
 531         if (len > d->mtu)
 532                 return -EINVAL;
 533
 534         rfcomm_make_uih(skb, d->addr);
 535         skb_queue_tail(&d->tx_queue, skb);
 536
 537         if (!test_bit(RFCOMM_TX_THROTTLED, &d->flags))
 538                 rfcomm_schedule();
 539         return len;
 540 }
 541
 542 void __rfcomm_dlc_throttle(struct rfcomm_dlc *d)
 543 {
 544         BT_DBG("dlc %p state %ld", d, d->state);
 545
 546         if (!d->cfc) {
 547                 d->v24_sig |= RFCOMM_V24_FC;
 548                 set_bit(RFCOMM_MSC_PENDING, &d->flags);
 549         }
 550         rfcomm_schedule();
 551 }
 552
 553 void __rfcomm_dlc_unthrottle(struct rfcomm_dlc *d)
 554 {
 555         BT_DBG("dlc %p state %ld", d, d->state);
 556
 557         if (!d->cfc) {
 558                 d->v24_sig &= ~RFCOMM_V24_FC;
 559                 set_bit(RFCOMM_MSC_PENDING, &d->flags);
 560         }
 561         rfcomm_schedule();
 562 }
 563
 564 /*
 565    Set/get modem status functions use _local_ status i.e. what we report
 566    to the other side.
 567    Remote status is provided by dlc->modem_status() callback.
 568  */
 569 int rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig)
 570 {
 571         BT_DBG("dlc %p state %ld v24_sig 0x%x",
 572                         d, d->state, v24_sig);
 573
 574         if (test_bit(RFCOMM_RX_THROTTLED, &d->flags))
 575                 v24_sig |= RFCOMM_V24_FC;
 576         else
 577                 v24_sig &= ~RFCOMM_V24_FC;
 578
 579         d->v24_sig = v24_sig;
 580
 581         if (!test_and_set_bit(RFCOMM_MSC_PENDING, &d->flags))
 582                 rfcomm_schedule();
 583
 584         return 0;
 585 }
 586
 587 int rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig)
 588 {
 589         BT_DBG("dlc %p state %ld v24_sig 0x%x",
 590                         d, d->state, d->v24_sig);
 591
 592         *v24_sig = d->v24_sig;
 593         return 0;
 594 }
 595
 596 /* ---- RFCOMM sessions ---- */
 597 static struct rfcomm_session *rfcomm_session_add(struct socket *sock, int state)
 598 {
 599         struct rfcomm_session *s = kzalloc(sizeof(*s), GFP_KERNEL);
 600
 601         if (!s)
 602                 return NULL;
 603
 604         BT_DBG("session %p sock %p", s, sock);
 605
 606         setup_timer(&s->timer, rfcomm_session_timeout, (unsigned long) s);
 607
 608         INIT_LIST_HEAD(&s->dlcs);
 609         s->state = state;
 610         s->sock  = sock;
 611
 612         s->mtu = RFCOMM_DEFAULT_MTU;
 613         s->cfc = disable_cfc ? RFCOMM_CFC_DISABLED : RFCOMM_CFC_UNKNOWN;
 614
 615         /* Do not increment module usage count for listening sessions.
 616          * Otherwise we won't be able to unload the module. */
 617         if (state != BT_LISTEN)
 618                 if (!try_module_get(THIS_MODULE)) {
 619                         kfree(s);
 620                         return NULL;
 621                 }
 622
 623         list_add(&s->list, &session_list);
 624
 625         return s;
 626 }
 627
 628 static void rfcomm_session_del(struct rfcomm_session *s)
 629 {
 630         int state = s->state;
 631
 632         BT_DBG("session %p state %ld", s, s->state);
 633
 634         list_del(&s->list);
 635
 636         if (state == BT_CONNECTED)
 637                 rfcomm_send_disc(s, 0);
 638
 639         rfcomm_session_clear_timer(s);
 640         sock_release(s->sock);
 641         kfree(s);
 642
 643         if (state != BT_LISTEN)
 644                 module_put(THIS_MODULE);
 645 }
 646
 647 static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst)
 648 {
 649         struct rfcomm_session *s;
 650         struct list_head *p, *n;
 651         struct bt_sock *sk;
 652         list_for_each_safe(p, n, &session_list) {
 653                 s = list_entry(p, struct rfcomm_session, list);
 654                 sk = bt_sk(s->sock->sk);
 655
 656                 if ((!bacmp(src, BDADDR_ANY) || !bacmp(&sk->src, src)) &&
 657                                 !bacmp(&sk->dst, dst))
 658                         return s;
 659         }
 660         return NULL;
 661 }
 662
 663 static void rfcomm_session_close(struct rfcomm_session *s, int err)
 664 {
 665         struct rfcomm_dlc *d;
 666         struct list_head *p, *n;
 667
 668         BT_DBG("session %p state %ld err %d", s, s->state, err);
 669
 670         rfcomm_session_hold(s);
 671
 672         s->state = BT_CLOSED;
 673
 674         /* Close all dlcs */
 675         list_for_each_safe(p, n, &s->dlcs) {
 676                 d = list_entry(p, struct rfcomm_dlc, list);
 677                 d->state = BT_CLOSED;
 678                 __rfcomm_dlc_close(d, err);
 679         }
 680
 681         rfcomm_session_clear_timer(s);
 682         rfcomm_session_put(s);
 683 }
 684
 685 static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
 686                                                         bdaddr_t *dst,
 687                                                         u8 sec_level,
 688                                                         int *err)
 689 {
 690         struct rfcomm_session *s = NULL;
 691         struct sockaddr_l2 addr;
 692         struct socket *sock;
 693         struct sock *sk;
 694
 695         BT_DBG("%s %s", batostr(src), batostr(dst));
 696
 697         *err = rfcomm_l2sock_create(&sock);
 698         if (*err < 0)
 699                 return NULL;
 700
 701         bacpy(&addr.l2_bdaddr, src);
 702         addr.l2_family = AF_BLUETOOTH;
 703         addr.l2_psm    = 0;
 704         addr.l2_cid    = 0;
 705         *err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
 706         if (*err < 0)
 707                 goto failed;
 708
 709         /* Set L2CAP options */
 710         sk = sock->sk;
 711         lock_sock(sk);
 712         l2cap_pi(sk)->chan->imtu = l2cap_mtu;
 713         l2cap_pi(sk)->chan->sec_level = sec_level;
 714         if (l2cap_ertm)
 715                 l2cap_pi(sk)->chan->mode = L2CAP_MODE_ERTM;
 716         release_sock(sk);
 717
 718         s = rfcomm_session_add(sock, BT_BOUND);
 719         if (!s) {
 720                 *err = -ENOMEM;
 721                 goto failed;
 722         }
 723
 724         s->initiator = 1;
 725
 726         bacpy(&addr.l2_bdaddr, dst);
 727         addr.l2_family = AF_BLUETOOTH;
 728         addr.l2_psm    = cpu_to_le16(RFCOMM_PSM);
 729         addr.l2_cid    = 0;
 730         *err = kernel_connect(sock, (struct sockaddr *) &addr, sizeof(addr), O_NONBLOCK);
 731         if (*err == 0 || *err == -EINPROGRESS)
 732                 return s;
 733
 734         rfcomm_session_del(s);
 735         return NULL;
 736
 737 failed:
 738         sock_release(sock);
 739         return NULL;
 740 }
 741
 742 void rfcomm_session_getaddr(struct rfcomm_session *s, bdaddr_t *src, bdaddr_t *dst)
 743 {
 744         struct sock *sk = s->sock->sk;
 745         if (src)
 746                 bacpy(src, &bt_sk(sk)->src);
 747         if (dst)
 748                 bacpy(dst, &bt_sk(sk)->dst);
 749 }
 750
 751 /* ---- RFCOMM frame sending ---- */
 752 static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len)
 753 {
 754         struct socket *sock = s->sock;
 755         struct kvec iv = { data, len };
 756         struct msghdr msg;
 757
 758         BT_DBG("session %p len %d", s, len);
 759
 760         memset(&msg, 0, sizeof(msg));
 761
 762         return kernel_sendmsg(sock, &msg, &iv, 1, len);
 763 }
 764
 765 static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci)
 766 {
 767         struct rfcomm_cmd cmd;
 768
 769         BT_DBG("%p dlci %d", s, dlci);
 770
 771         cmd.addr = __addr(s->initiator, dlci);
 772         cmd.ctrl = __ctrl(RFCOMM_SABM, 1);
 773         cmd.len  = __len8(0);
 774         cmd.fcs  = __fcs2((u8 *) &cmd);
 775
 776         return rfcomm_send_frame(s, (void *) &cmd, sizeof(cmd));
 777 }
 778
 779 static int rfcomm_send_ua(struct rfcomm_session *s, u8 dlci)
 780 {
 781         struct rfcomm_cmd cmd;
 782
 783         BT_DBG("%p dlci %d", s, dlci);
 784
 785         cmd.addr = __addr(!s->initiator, dlci);
 786         cmd.ctrl = __ctrl(RFCOMM_UA, 1);
 787         cmd.len  = __len8(0);
 788         cmd.fcs  = __fcs2((u8 *) &cmd);
 789
 790         return rfcomm_send_frame(s, (void *) &cmd, sizeof(cmd));
 791 }
 792
 793 static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci)
 794 {
 795         struct rfcomm_cmd cmd;
 796
 797         BT_DBG("%p dlci %d", s, dlci);
 798
 799         cmd.addr = __addr(s->initiator, dlci);
 800         cmd.ctrl = __ctrl(RFCOMM_DISC, 1);
 801         cmd.len  = __len8(0);
 802         cmd.fcs  = __fcs2((u8 *) &cmd);
 803
 804         return rfcomm_send_frame(s, (void *) &cmd, sizeof(cmd));
 805 }
 806
 807 static int rfcomm_queue_disc(struct rfcomm_dlc *d)
 808 {
 809         struct rfcomm_cmd *cmd;
 810         struct sk_buff *skb;
 811
 812         BT_DBG("dlc %p dlci %d", d, d->dlci);
 813
 814         skb = alloc_skb(sizeof(*cmd), GFP_KERNEL);
 815         if (!skb)
 816                 return -ENOMEM;
 817
 818         cmd = (void *) __skb_put(skb, sizeof(*cmd));
 819         cmd->addr = d->addr;
 820         cmd->ctrl = __ctrl(RFCOMM_DISC, 1);
 821         cmd->len  = __len8(0);
 822         cmd->fcs  = __fcs2((u8 *) cmd);
 823
 824         skb_queue_tail(&d->tx_queue, skb);
 825         rfcomm_schedule();
 826         return 0;
 827 }
 828
 829 static int rfcomm_send_dm(struct rfcomm_session *s, u8 dlci)
 830 {
 831         struct rfcomm_cmd cmd;
 832
 833         BT_DBG("%p dlci %d", s, dlci);
 834
 835         cmd.addr = __addr(!s->initiator, dlci);
 836         cmd.ctrl = __ctrl(RFCOMM_DM, 1);
 837         cmd.len  = __len8(0);
 838         cmd.fcs  = __fcs2((u8 *) &cmd);
 839
 840         return rfcomm_send_frame(s, (void *) &cmd, sizeof(cmd));
 841 }
 842
 843 static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type)
 844 {
 845         struct rfcomm_hdr *hdr;
 846         struct rfcomm_mcc *mcc;
 847         u8 buf[16], *ptr = buf;
 848
 849         BT_DBG("%p cr %d type %d", s, cr, type);
 850
 851         hdr = (void *) ptr; ptr += sizeof(*hdr);
 852         hdr->addr = __addr(s->initiator, 0);
 853         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 854         hdr->len  = __len8(sizeof(*mcc) + 1);
 855
 856         mcc = (void *) ptr; ptr += sizeof(*mcc);
 857         mcc->type = __mcc_type(cr, RFCOMM_NSC);
 858         mcc->len  = __len8(1);
 859
 860         /* Type that we didn't like */
 861         *ptr = __mcc_type(cr, type); ptr++;
 862
 863         *ptr = __fcs(buf); ptr++;
 864
 865         return rfcomm_send_frame(s, buf, ptr - buf);
 866 }
 867
 868 static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d)
 869 {
 870         struct rfcomm_hdr *hdr;
 871         struct rfcomm_mcc *mcc;
 872         struct rfcomm_pn  *pn;
 873         u8 buf[16], *ptr = buf;
 874
 875         BT_DBG("%p cr %d dlci %d mtu %d", s, cr, d->dlci, d->mtu);
 876
 877         hdr = (void *) ptr; ptr += sizeof(*hdr);
 878         hdr->addr = __addr(s->initiator, 0);
 879         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 880         hdr->len  = __len8(sizeof(*mcc) + sizeof(*pn));
 881
 882         mcc = (void *) ptr; ptr += sizeof(*mcc);
 883         mcc->type = __mcc_type(cr, RFCOMM_PN);
 884         mcc->len  = __len8(sizeof(*pn));
 885
 886         pn = (void *) ptr; ptr += sizeof(*pn);
 887         pn->dlci        = d->dlci;
 888         pn->priority    = d->priority;
 889         pn->ack_timer   = 0;
 890         pn->max_retrans = 0;
 891
 892         if (s->cfc) {
 893                 pn->flow_ctrl = cr ? 0xf0 : 0xe0;
 894                 pn->credits = RFCOMM_DEFAULT_CREDITS;
 895         } else {
 896                 pn->flow_ctrl = 0;
 897                 pn->credits   = 0;
 898         }
 899
 900         if (cr && channel_mtu >= 0)
 901                 pn->mtu = cpu_to_le16(channel_mtu);
 902         else
 903                 pn->mtu = cpu_to_le16(d->mtu);
 904
 905         *ptr = __fcs(buf); ptr++;
 906
 907         return rfcomm_send_frame(s, buf, ptr - buf);
 908 }
 909
 910 int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
 911                         u8 bit_rate, u8 data_bits, u8 stop_bits,
 912                         u8 parity, u8 flow_ctrl_settings,
 913                         u8 xon_char, u8 xoff_char, u16 param_mask)
 914 {
 915         struct rfcomm_hdr *hdr;
 916         struct rfcomm_mcc *mcc;
 917         struct rfcomm_rpn *rpn;
 918         u8 buf[16], *ptr = buf;
 919
 920         BT_DBG("%p cr %d dlci %d bit_r 0x%x data_b 0x%x stop_b 0x%x parity 0x%x"
 921                         " flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x",
 922                 s, cr, dlci, bit_rate, data_bits, stop_bits, parity,
 923                 flow_ctrl_settings, xon_char, xoff_char, param_mask);
 924
 925         hdr = (void *) ptr; ptr += sizeof(*hdr);
 926         hdr->addr = __addr(s->initiator, 0);
 927         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 928         hdr->len  = __len8(sizeof(*mcc) + sizeof(*rpn));
 929
 930         mcc = (void *) ptr; ptr += sizeof(*mcc);
 931         mcc->type = __mcc_type(cr, RFCOMM_RPN);
 932         mcc->len  = __len8(sizeof(*rpn));
 933
 934         rpn = (void *) ptr; ptr += sizeof(*rpn);
 935         rpn->dlci          = __addr(1, dlci);
 936         rpn->bit_rate      = bit_rate;
 937         rpn->line_settings = __rpn_line_settings(data_bits, stop_bits, parity);
 938         rpn->flow_ctrl     = flow_ctrl_settings;
 939         rpn->xon_char      = xon_char;
 940         rpn->xoff_char     = xoff_char;
 941         rpn->param_mask    = cpu_to_le16(param_mask);
 942
 943         *ptr = __fcs(buf); ptr++;
 944
 945         return rfcomm_send_frame(s, buf, ptr - buf);
 946 }
 947
 948 static int rfcomm_send_rls(struct rfcomm_session *s, int cr, u8 dlci, u8 status)
 949 {
 950         struct rfcomm_hdr *hdr;
 951         struct rfcomm_mcc *mcc;
 952         struct rfcomm_rls *rls;
 953         u8 buf[16], *ptr = buf;
 954
 955         BT_DBG("%p cr %d status 0x%x", s, cr, status);
 956
 957         hdr = (void *) ptr; ptr += sizeof(*hdr);
 958         hdr->addr = __addr(s->initiator, 0);
 959         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 960         hdr->len  = __len8(sizeof(*mcc) + sizeof(*rls));
 961
 962         mcc = (void *) ptr; ptr += sizeof(*mcc);
 963         mcc->type = __mcc_type(cr, RFCOMM_RLS);
 964         mcc->len  = __len8(sizeof(*rls));
 965
 966         rls = (void *) ptr; ptr += sizeof(*rls);
 967         rls->dlci   = __addr(1, dlci);
 968         rls->status = status;
 969
 970         *ptr = __fcs(buf); ptr++;
 971
 972         return rfcomm_send_frame(s, buf, ptr - buf);
 973 }
 974
 975 static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig)
 976 {
 977         struct rfcomm_hdr *hdr;
 978         struct rfcomm_mcc *mcc;
 979         struct rfcomm_msc *msc;
 980         u8 buf[16], *ptr = buf;
 981
 982         BT_DBG("%p cr %d v24 0x%x", s, cr, v24_sig);
 983
 984         hdr = (void *) ptr; ptr += sizeof(*hdr);
 985         hdr->addr = __addr(s->initiator, 0);
 986         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 987         hdr->len  = __len8(sizeof(*mcc) + sizeof(*msc));
 988
 989         mcc = (void *) ptr; ptr += sizeof(*mcc);
 990         mcc->type = __mcc_type(cr, RFCOMM_MSC);
 991         mcc->len  = __len8(sizeof(*msc));
 992
 993         msc = (void *) ptr; ptr += sizeof(*msc);
 994         msc->dlci    = __addr(1, dlci);
 995         msc->v24_sig = v24_sig | 0x01;
 996
 997         *ptr = __fcs(buf); ptr++;
 998
 999         return rfcomm_send_frame(s, buf, ptr - buf);
1000 }
1001
1002 static int rfcomm_send_fcoff(struct rfcomm_session *s, int cr)
1003 {
1004         struct rfcomm_hdr *hdr;
1005         struct rfcomm_mcc *mcc;
1006         u8 buf[16], *ptr = buf;
1007
1008         BT_DBG("%p cr %d", s, cr);
1009
1010         hdr = (void *) ptr; ptr += sizeof(*hdr);
1011         hdr->addr = __addr(s->initiator, 0);
1012         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1013         hdr->len  = __len8(sizeof(*mcc));
1014
1015         mcc = (void *) ptr; ptr += sizeof(*mcc);
1016         mcc->type = __mcc_type(cr, RFCOMM_FCOFF);
1017         mcc->len  = __len8(0);
1018
1019         *ptr = __fcs(buf); ptr++;
1020
1021         return rfcomm_send_frame(s, buf, ptr - buf);
1022 }
1023
1024 static int rfcomm_send_fcon(struct rfcomm_session *s, int cr)
1025 {
1026         struct rfcomm_hdr *hdr;
1027         struct rfcomm_mcc *mcc;
1028         u8 buf[16], *ptr = buf;
1029
1030         BT_DBG("%p cr %d", s, cr);
1031
1032         hdr = (void *) ptr; ptr += sizeof(*hdr);
1033         hdr->addr = __addr(s->initiator, 0);
1034         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1035         hdr->len  = __len8(sizeof(*mcc));
1036
1037         mcc = (void *) ptr; ptr += sizeof(*mcc);
1038         mcc->type = __mcc_type(cr, RFCOMM_FCON);
1039         mcc->len  = __len8(0);
1040
1041         *ptr = __fcs(buf); ptr++;
1042
1043         return rfcomm_send_frame(s, buf, ptr - buf);
1044 }
1045
1046 static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len)
1047 {
1048         struct socket *sock = s->sock;
1049         struct kvec iv[3];
1050         struct msghdr msg;
1051         unsigned char hdr[5], crc[1];
1052
1053         if (len > 125)
1054                 return -EINVAL;
1055
1056         BT_DBG("%p cr %d", s, cr);
1057
1058         hdr[0] = __addr(s->initiator, 0);
1059         hdr[1] = __ctrl(RFCOMM_UIH, 0);
1060         hdr[2] = 0x01 | ((len + 2) << 1);
1061         hdr[3] = 0x01 | ((cr & 0x01) << 1) | (RFCOMM_TEST << 2);
1062         hdr[4] = 0x01 | (len << 1);
1063
1064         crc[0] = __fcs(hdr);
1065
1066         iv[0].iov_base = hdr;
1067         iv[0].iov_len  = 5;
1068         iv[1].iov_base = pattern;
1069         iv[1].iov_len  = len;
1070         iv[2].iov_base = crc;
1071         iv[2].iov_len  = 1;
1072
1073         memset(&msg, 0, sizeof(msg));
1074
1075         return kernel_sendmsg(sock, &msg, iv, 3, 6 + len);
1076 }
1077
1078 static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits)
1079 {
1080         struct rfcomm_hdr *hdr;
1081         u8 buf[16], *ptr = buf;
1082
1083         BT_DBG("%p addr %d credits %d", s, addr, credits);
1084
1085         hdr = (void *) ptr; ptr += sizeof(*hdr);
1086         hdr->addr = addr;
1087         hdr->ctrl = __ctrl(RFCOMM_UIH, 1);
1088         hdr->len  = __len8(0);
1089
1090         *ptr = credits; ptr++;
1091
1092         *ptr = __fcs(buf); ptr++;
1093
1094         return rfcomm_send_frame(s, buf, ptr - buf);
1095 }
1096
1097 static void rfcomm_make_uih(struct sk_buff *skb, u8 addr)
1098 {
1099         struct rfcomm_hdr *hdr;
1100         int len = skb->len;
1101         u8 *crc;
1102
1103         if (len > 127) {
1104                 hdr = (void *) skb_push(skb, 4);
1105                 put_unaligned(cpu_to_le16(__len16(len)), (__le16 *) &hdr->len);
1106         } else {
1107                 hdr = (void *) skb_push(skb, 3);
1108                 hdr->len = __len8(len);
1109         }
1110         hdr->addr = addr;
1111         hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1112
1113         crc = skb_put(skb, 1);
1114         *crc = __fcs((void *) hdr);
1115 }
1116
1117 /* ---- RFCOMM frame reception ---- */
1118 static int rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci)
1119 {
1120         BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1121
1122         if (dlci) {
1123                 /* Data channel */
1124                 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1125                 if (!d) {
1126                         rfcomm_send_dm(s, dlci);
1127                         return 0;
1128                 }
1129
1130                 switch (d->state) {
1131                 case BT_CONNECT:
1132                         rfcomm_dlc_clear_timer(d);
1133
1134                         rfcomm_dlc_lock(d);
1135                         d->state = BT_CONNECTED;
1136                         d->state_change(d, 0);
1137                         rfcomm_dlc_unlock(d);
1138
1139                         rfcomm_send_msc(s, 1, dlci, d->v24_sig);
1140                         break;
1141
1142                 case BT_DISCONN:
1143                         d->state = BT_CLOSED;
1144                         __rfcomm_dlc_close(d, 0);
1145
1146                         if (list_empty(&s->dlcs)) {
1147                                 s->state = BT_DISCONN;
1148                                 rfcomm_send_disc(s, 0);
1149                         }
1150
1151                         break;
1152                 }
1153         } else {
1154                 /* Control channel */
1155                 switch (s->state) {
1156                 case BT_CONNECT:
1157                         s->state = BT_CONNECTED;
1158                         rfcomm_process_connect(s);
1159                         break;
1160
1161                 case BT_DISCONN:
1162                         /* When socket is closed and we are not RFCOMM
1163                          * initiator rfcomm_process_rx already calls
1164                          * rfcomm_session_put() */
1165                         if (s->sock->sk->sk_state != BT_CLOSED)
1166                                 if (list_empty(&s->dlcs))
1167                                         rfcomm_session_put(s);
1168                         break;
1169                 }
1170         }
1171         return 0;
1172 }
1173
1174 static int rfcomm_recv_dm(struct rfcomm_session *s, u8 dlci)
1175 {
1176         int err = 0;
1177
1178         BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1179
1180         if (dlci) {
1181                 /* Data DLC */
1182                 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1183                 if (d) {
1184                         if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1185                                 err = ECONNREFUSED;
1186                         else
1187                                 err = ECONNRESET;
1188
1189                         d->state = BT_CLOSED;
1190                         __rfcomm_dlc_close(d, err);
1191                 }
1192         } else {
1193                 if (s->state == BT_CONNECT)
1194                         err = ECONNREFUSED;
1195                 else
1196                         err = ECONNRESET;
1197
1198                 s->state = BT_CLOSED;
1199                 rfcomm_session_close(s, err);
1200         }
1201         return 0;
1202 }
1203
1204 static int rfcomm_recv_disc(struct rfcomm_session *s, u8 dlci)
1205 {
1206         int err = 0;
1207
1208         BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1209
1210         if (dlci) {
1211                 struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1212                 if (d) {
1213                         rfcomm_send_ua(s, dlci);
1214
1215                         if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1216                                 err = ECONNREFUSED;
1217                         else
1218                                 err = ECONNRESET;
1219
1220                         d->state = BT_CLOSED;
1221                         __rfcomm_dlc_close(d, err);
1222                 } else
1223                         rfcomm_send_dm(s, dlci);
1224
1225         } else {
1226                 rfcomm_send_ua(s, 0);
1227
1228                 if (s->state == BT_CONNECT)
1229                         err = ECONNREFUSED;
1230                 else
1231                         err = ECONNRESET;
1232
1233                 s->state = BT_CLOSED;
1234                 rfcomm_session_close(s, err);
1235         }
1236
1237         return 0;
1238 }
1239
1240 void rfcomm_dlc_accept(struct rfcomm_dlc *d)
1241 {
1242         struct sock *sk = d->session->sock->sk;
1243         struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
1244
1245         BT_DBG("dlc %p", d);
1246
1247         rfcomm_send_ua(d->session, d->dlci);
1248
1249         rfcomm_dlc_clear_timer(d);
1250
1251         rfcomm_dlc_lock(d);
1252         d->state = BT_CONNECTED;
1253         d->state_change(d, 0);
1254         rfcomm_dlc_unlock(d);
1255
1256         if (d->role_switch)
1257                 hci_conn_switch_role(conn->hcon, 0x00);
1258
1259         rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1260 }
1261
1262 static void rfcomm_check_accept(struct rfcomm_dlc *d)
1263 {
1264         if (rfcomm_check_security(d)) {
1265                 if (d->defer_setup) {
1266                         set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1267                         rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1268
1269                         rfcomm_dlc_lock(d);
1270                         d->state = BT_CONNECT2;
1271                         d->state_change(d, 0);
1272                         rfcomm_dlc_unlock(d);
1273                 } else
1274                         rfcomm_dlc_accept(d);
1275         } else {
1276                 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1277                 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1278         }
1279 }
1280
1281 static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
1282 {
1283         struct rfcomm_dlc *d;
1284         u8 channel;
1285
1286         BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1287
1288         if (!dlci) {
1289                 rfcomm_send_ua(s, 0);
1290
1291                 if (s->state == BT_OPEN) {
1292                         s->state = BT_CONNECTED;
1293                         rfcomm_process_connect(s);
1294                 }
1295                 return 0;
1296         }
1297
1298         /* Check if DLC exists */
1299         d = rfcomm_dlc_get(s, dlci);
1300         if (d) {
1301                 if (d->state == BT_OPEN) {
1302                         /* DLC was previously opened by PN request */
1303                         rfcomm_check_accept(d);
1304                 }
1305                 return 0;
1306         }
1307
1308         /* Notify socket layer about incoming connection */
1309         channel = __srv_channel(dlci);
1310         if (rfcomm_connect_ind(s, channel, &d)) {
1311                 d->dlci = dlci;
1312                 d->addr = __addr(s->initiator, dlci);
1313                 rfcomm_dlc_link(s, d);
1314
1315                 rfcomm_check_accept(d);
1316         } else {
1317                 rfcomm_send_dm(s, dlci);
1318         }
1319
1320         return 0;
1321 }
1322
1323 static int rfcomm_apply_pn(struct rfcomm_dlc *d, int cr, struct rfcomm_pn *pn)
1324 {
1325         struct rfcomm_session *s = d->session;
1326
1327         BT_DBG("dlc %p state %ld dlci %d mtu %d fc 0x%x credits %d",
1328                         d, d->state, d->dlci, pn->mtu, pn->flow_ctrl, pn->credits);
1329
1330         if ((pn->flow_ctrl == 0xf0 && s->cfc != RFCOMM_CFC_DISABLED) ||
1331                                                 pn->flow_ctrl == 0xe0) {
1332                 d->cfc = RFCOMM_CFC_ENABLED;
1333                 d->tx_credits = pn->credits;
1334         } else {
1335                 d->cfc = RFCOMM_CFC_DISABLED;
1336                 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1337         }
1338
1339         if (s->cfc == RFCOMM_CFC_UNKNOWN)
1340                 s->cfc = d->cfc;
1341
1342         d->priority = pn->priority;
1343
1344         d->mtu = __le16_to_cpu(pn->mtu);
1345
1346         if (cr && d->mtu > s->mtu)
1347                 d->mtu = s->mtu;
1348
1349         return 0;
1350 }
1351
1352 static int rfcomm_recv_pn(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1353 {
1354         struct rfcomm_pn *pn = (void *) skb->data;
1355         struct rfcomm_dlc *d;
1356         u8 dlci = pn->dlci;
1357
1358         BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1359
1360         if (!dlci)
1361                 return 0;
1362
1363         d = rfcomm_dlc_get(s, dlci);
1364         if (d) {
1365                 if (cr) {
1366                         /* PN request */
1367                         rfcomm_apply_pn(d, cr, pn);
1368                         rfcomm_send_pn(s, 0, d);
1369                 } else {
1370                         /* PN response */
1371                         switch (d->state) {
1372                         case BT_CONFIG:
1373                                 rfcomm_apply_pn(d, cr, pn);
1374
1375                                 d->state = BT_CONNECT;
1376                                 rfcomm_send_sabm(s, d->dlci);
1377                                 break;
1378                         }
1379                 }
1380         } else {
1381                 u8 channel = __srv_channel(dlci);
1382
1383                 if (!cr)
1384                         return 0;
1385
1386                 /* PN request for non existing DLC.
1387                  * Assume incoming connection. */
1388                 if (rfcomm_connect_ind(s, channel, &d)) {
1389                         d->dlci = dlci;
1390                         d->addr = __addr(s->initiator, dlci);
1391                         rfcomm_dlc_link(s, d);
1392
1393                         rfcomm_apply_pn(d, cr, pn);
1394
1395                         d->state = BT_OPEN;
1396                         rfcomm_send_pn(s, 0, d);
1397                 } else {
1398                         rfcomm_send_dm(s, dlci);
1399                 }
1400         }
1401         return 0;
1402 }
1403
1404 static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_buff *skb)
1405 {
1406         struct rfcomm_rpn *rpn = (void *) skb->data;
1407         u8 dlci = __get_dlci(rpn->dlci);
1408
1409         u8 bit_rate  = 0;
1410         u8 data_bits = 0;
1411         u8 stop_bits = 0;
1412         u8 parity    = 0;
1413         u8 flow_ctrl = 0;
1414         u8 xon_char  = 0;
1415         u8 xoff_char = 0;
1416         u16 rpn_mask = RFCOMM_RPN_PM_ALL;
1417
1418         BT_DBG("dlci %d cr %d len 0x%x bitr 0x%x line 0x%x flow 0x%x xonc 0x%x xoffc 0x%x pm 0x%x",
1419                 dlci, cr, len, rpn->bit_rate, rpn->line_settings, rpn->flow_ctrl,
1420                 rpn->xon_char, rpn->xoff_char, rpn->param_mask);
1421
1422         if (!cr)
1423                 return 0;
1424
1425         if (len == 1) {
1426                 /* This is a request, return default (according to ETSI TS 07.10) settings */
1427                 bit_rate  = RFCOMM_RPN_BR_9600;
1428                 data_bits = RFCOMM_RPN_DATA_8;
1429                 stop_bits = RFCOMM_RPN_STOP_1;
1430                 parity    = RFCOMM_RPN_PARITY_NONE;
1431                 flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1432                 xon_char  = RFCOMM_RPN_XON_CHAR;
1433                 xoff_char = RFCOMM_RPN_XOFF_CHAR;
1434                 goto rpn_out;
1435         }
1436
1437         /* Check for sane values, ignore/accept bit_rate, 8 bits, 1 stop bit,
1438          * no parity, no flow control lines, normal XON/XOFF chars */
1439
1440         if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_BITRATE)) {
1441                 bit_rate = rpn->bit_rate;
1442                 if (bit_rate > RFCOMM_RPN_BR_230400) {
1443                         BT_DBG("RPN bit rate mismatch 0x%x", bit_rate);
1444                         bit_rate = RFCOMM_RPN_BR_9600;
1445                         rpn_mask ^= RFCOMM_RPN_PM_BITRATE;
1446                 }
1447         }
1448
1449         if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_DATA)) {
1450                 data_bits = __get_rpn_data_bits(rpn->line_settings);
1451                 if (data_bits != RFCOMM_RPN_DATA_8) {
1452                         BT_DBG("RPN data bits mismatch 0x%x", data_bits);
1453                         data_bits = RFCOMM_RPN_DATA_8;
1454                         rpn_mask ^= RFCOMM_RPN_PM_DATA;
1455                 }
1456         }
1457
1458         if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_STOP)) {
1459                 stop_bits = __get_rpn_stop_bits(rpn->line_settings);
1460                 if (stop_bits != RFCOMM_RPN_STOP_1) {
1461                         BT_DBG("RPN stop bits mismatch 0x%x", stop_bits);
1462                         stop_bits = RFCOMM_RPN_STOP_1;
1463                         rpn_mask ^= RFCOMM_RPN_PM_STOP;
1464                 }
1465         }
1466
1467         if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_PARITY)) {
1468                 parity = __get_rpn_parity(rpn->line_settings);
1469                 if (parity != RFCOMM_RPN_PARITY_NONE) {
1470                         BT_DBG("RPN parity mismatch 0x%x", parity);
1471                         parity = RFCOMM_RPN_PARITY_NONE;
1472                         rpn_mask ^= RFCOMM_RPN_PM_PARITY;
1473                 }
1474         }
1475
1476         if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_FLOW)) {
1477                 flow_ctrl = rpn->flow_ctrl;
1478                 if (flow_ctrl != RFCOMM_RPN_FLOW_NONE) {
1479                         BT_DBG("RPN flow ctrl mismatch 0x%x", flow_ctrl);
1480                         flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1481                         rpn_mask ^= RFCOMM_RPN_PM_FLOW;
1482                 }
1483         }
1484
1485         if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XON)) {
1486                 xon_char = rpn->xon_char;
1487                 if (xon_char != RFCOMM_RPN_XON_CHAR) {
1488                         BT_DBG("RPN XON char mismatch 0x%x", xon_char);
1489                         xon_char = RFCOMM_RPN_XON_CHAR;
1490                         rpn_mask ^= RFCOMM_RPN_PM_XON;
1491                 }
1492         }
1493
1494         if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XOFF)) {
1495                 xoff_char = rpn->xoff_char;
1496                 if (xoff_char != RFCOMM_RPN_XOFF_CHAR) {
1497                         BT_DBG("RPN XOFF char mismatch 0x%x", xoff_char);
1498                         xoff_char = RFCOMM_RPN_XOFF_CHAR;
1499                         rpn_mask ^= RFCOMM_RPN_PM_XOFF;
1500                 }
1501         }
1502
1503 rpn_out:
1504         rfcomm_send_rpn(s, 0, dlci, bit_rate, data_bits, stop_bits,
1505                         parity, flow_ctrl, xon_char, xoff_char, rpn_mask);
1506
1507         return 0;
1508 }
1509
1510 static int rfcomm_recv_rls(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1511 {
1512         struct rfcomm_rls *rls = (void *) skb->data;
1513         u8 dlci = __get_dlci(rls->dlci);
1514
1515         BT_DBG("dlci %d cr %d status 0x%x", dlci, cr, rls->status);
1516
1517         if (!cr)
1518                 return 0;
1519
1520         /* We should probably do something with this information here. But
1521          * for now it's sufficient just to reply -- Bluetooth 1.1 says it's
1522          * mandatory to recognise and respond to RLS */
1523
1524         rfcomm_send_rls(s, 0, dlci, rls->status);
1525
1526         return 0;
1527 }
1528
1529 static int rfcomm_recv_msc(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1530 {
1531         struct rfcomm_msc *msc = (void *) skb->data;
1532         struct rfcomm_dlc *d;
1533         u8 dlci = __get_dlci(msc->dlci);
1534
1535         BT_DBG("dlci %d cr %d v24 0x%x", dlci, cr, msc->v24_sig);
1536
1537         d = rfcomm_dlc_get(s, dlci);
1538         if (!d)
1539                 return 0;
1540
1541         if (cr) {
1542                 if (msc->v24_sig & RFCOMM_V24_FC && !d->cfc)
1543                         set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1544                 else
1545                         clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1546
1547                 rfcomm_dlc_lock(d);
1548
1549                 d->remote_v24_sig = msc->v24_sig;
1550
1551                 if (d->modem_status)
1552                         d->modem_status(d, msc->v24_sig);
1553
1554                 rfcomm_dlc_unlock(d);
1555
1556                 rfcomm_send_msc(s, 0, dlci, msc->v24_sig);
1557
1558                 d->mscex |= RFCOMM_MSCEX_RX;
1559         } else
1560                 d->mscex |= RFCOMM_MSCEX_TX;
1561
1562         return 0;
1563 }
1564
1565 static int rfcomm_recv_mcc(struct rfcomm_session *s, struct sk_buff *skb)
1566 {
1567         struct rfcomm_mcc *mcc = (void *) skb->data;
1568         u8 type, cr, len;
1569
1570         cr   = __test_cr(mcc->type);
1571         type = __get_mcc_type(mcc->type);
1572         len  = __get_mcc_len(mcc->len);
1573
1574         BT_DBG("%p type 0x%x cr %d", s, type, cr);
1575
1576         skb_pull(skb, 2);
1577
1578         switch (type) {
1579         case RFCOMM_PN:
1580                 rfcomm_recv_pn(s, cr, skb);
1581                 break;
1582
1583         case RFCOMM_RPN:
1584                 rfcomm_recv_rpn(s, cr, len, skb);
1585                 break;
1586
1587         case RFCOMM_RLS:
1588                 rfcomm_recv_rls(s, cr, skb);
1589                 break;
1590
1591         case RFCOMM_MSC:
1592                 rfcomm_recv_msc(s, cr, skb);
1593                 break;
1594
1595         case RFCOMM_FCOFF:
1596                 if (cr) {
1597                         set_bit(RFCOMM_TX_THROTTLED, &s->flags);
1598                         rfcomm_send_fcoff(s, 0);
1599                 }
1600                 break;
1601
1602         case RFCOMM_FCON:
1603                 if (cr) {
1604                         clear_bit(RFCOMM_TX_THROTTLED, &s->flags);
1605                         rfcomm_send_fcon(s, 0);
1606                 }
1607                 break;
1608
1609         case RFCOMM_TEST:
1610                 if (cr)
1611                         rfcomm_send_test(s, 0, skb->data, skb->len);
1612                 break;
1613
1614         case RFCOMM_NSC:
1615                 break;
1616
1617         default:
1618                 BT_ERR("Unknown control type 0x%02x", type);
1619                 rfcomm_send_nsc(s, cr, type);
1620                 break;
1621         }
1622         return 0;
1623 }
1624
1625 static int rfcomm_recv_data(struct rfcomm_session *s, u8 dlci, int pf, struct sk_buff *skb)
1626 {
1627         struct rfcomm_dlc *d;
1628
1629         BT_DBG("session %p state %ld dlci %d pf %d", s, s->state, dlci, pf);
1630
1631         d = rfcomm_dlc_get(s, dlci);
1632         if (!d) {
1633                 rfcomm_send_dm(s, dlci);
1634                 goto drop;
1635         }
1636
1637         if (pf && d->cfc) {
1638                 u8 credits = *(u8 *) skb->data; skb_pull(skb, 1);
1639
1640                 d->tx_credits += credits;
1641                 if (d->tx_credits)
1642                         clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1643         }
1644
1645         if (skb->len && d->state == BT_CONNECTED) {
1646                 rfcomm_dlc_lock(d);
1647                 d->rx_credits--;
1648                 d->data_ready(d, skb);
1649                 rfcomm_dlc_unlock(d);
1650                 return 0;
1651         }
1652
1653 drop:
1654         kfree_skb(skb);
1655         return 0;
1656 }
1657
1658 static int rfcomm_recv_frame(struct rfcomm_session *s, struct sk_buff *skb)
1659 {
1660         struct rfcomm_hdr *hdr = (void *) skb->data;
1661         u8 type, dlci, fcs;
1662
1663         dlci = __get_dlci(hdr->addr);
1664         type = __get_type(hdr->ctrl);
1665
1666         /* Trim FCS */
1667         skb->len--; skb->tail--;
1668         fcs = *(u8 *)skb_tail_pointer(skb);
1669
1670         if (__check_fcs(skb->data, type, fcs)) {
1671                 BT_ERR("bad checksum in packet");
1672                 kfree_skb(skb);
1673                 return -EILSEQ;
1674         }
1675
1676         if (__test_ea(hdr->len))
1677                 skb_pull(skb, 3);
1678         else
1679                 skb_pull(skb, 4);
1680
1681         switch (type) {
1682         case RFCOMM_SABM:
1683                 if (__test_pf(hdr->ctrl))
1684                         rfcomm_recv_sabm(s, dlci);
1685                 break;
1686
1687         case RFCOMM_DISC:
1688                 if (__test_pf(hdr->ctrl))
1689                         rfcomm_recv_disc(s, dlci);
1690                 break;
1691
1692         case RFCOMM_UA:
1693                 if (__test_pf(hdr->ctrl))
1694                         rfcomm_recv_ua(s, dlci);
1695                 break;
1696
1697         case RFCOMM_DM:
1698                 rfcomm_recv_dm(s, dlci);
1699                 break;
1700
1701         case RFCOMM_UIH:
1702                 if (dlci)
1703                         return rfcomm_recv_data(s, dlci, __test_pf(hdr->ctrl), skb);
1704
1705                 rfcomm_recv_mcc(s, skb);
1706                 break;
1707
1708         default:
1709                 BT_ERR("Unknown packet type 0x%02x", type);
1710                 break;
1711         }
1712         kfree_skb(skb);
1713         return 0;
1714 }
1715
1716 /* ---- Connection and data processing ---- */
1717
1718 static void rfcomm_process_connect(struct rfcomm_session *s)
1719 {
1720         struct rfcomm_dlc *d;
1721         struct list_head *p, *n;
1722
1723         BT_DBG("session %p state %ld", s, s->state);
1724
1725         list_for_each_safe(p, n, &s->dlcs) {
1726                 d = list_entry(p, struct rfcomm_dlc, list);
1727                 if (d->state == BT_CONFIG) {
1728                         d->mtu = s->mtu;
1729                         if (rfcomm_check_security(d)) {
1730                                 rfcomm_send_pn(s, 1, d);
1731                         } else {
1732                                 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1733                                 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1734                         }
1735                 }
1736         }
1737 }
1738
1739 /* Send data queued for the DLC.
1740  * Return number of frames left in the queue.
1741  */
1742 static inline int rfcomm_process_tx(struct rfcomm_dlc *d)
1743 {
1744         struct sk_buff *skb;
1745         int err;
1746
1747         BT_DBG("dlc %p state %ld cfc %d rx_credits %d tx_credits %d",
1748                         d, d->state, d->cfc, d->rx_credits, d->tx_credits);
1749
1750         /* Send pending MSC */
1751         if (test_and_clear_bit(RFCOMM_MSC_PENDING, &d->flags))
1752                 rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1753
1754         if (d->cfc) {
1755                 /* CFC enabled.
1756                  * Give them some credits */
1757                 if (!test_bit(RFCOMM_RX_THROTTLED, &d->flags) &&
1758                                 d->rx_credits <= (d->cfc >> 2)) {
1759                         rfcomm_send_credits(d->session, d->addr, d->cfc - d->rx_credits);
1760                         d->rx_credits = d->cfc;
1761                 }
1762         } else {
1763                 /* CFC disabled.
1764                  * Give ourselves some credits */
1765                 d->tx_credits = 5;
1766         }
1767
1768         if (test_bit(RFCOMM_TX_THROTTLED, &d->flags))
1769                 return skb_queue_len(&d->tx_queue);
1770
1771         while (d->tx_credits && (skb = skb_dequeue(&d->tx_queue))) {
1772                 err = rfcomm_send_frame(d->session, skb->data, skb->len);
1773                 if (err < 0) {
1774                         skb_queue_head(&d->tx_queue, skb);
1775                         break;
1776                 }
1777                 kfree_skb(skb);
1778                 d->tx_credits--;
1779         }
1780
1781         if (d->cfc && !d->tx_credits) {
1782                 /* We're out of TX credits.
1783                  * Set TX_THROTTLED flag to avoid unnesary wakeups by dlc_send. */
1784                 set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1785         }
1786
1787         return skb_queue_len(&d->tx_queue);
1788 }
1789
1790 static inline void rfcomm_process_dlcs(struct rfcomm_session *s)
1791 {
1792         struct rfcomm_dlc *d;
1793         struct list_head *p, *n;
1794
1795         BT_DBG("session %p state %ld", s, s->state);
1796
1797         list_for_each_safe(p, n, &s->dlcs) {
1798                 d = list_entry(p, struct rfcomm_dlc, list);
1799
1800                 if (test_bit(RFCOMM_TIMED_OUT, &d->flags)) {
1801                         __rfcomm_dlc_close(d, ETIMEDOUT);
1802                         continue;
1803                 }
1804
1805                 if (test_and_clear_bit(RFCOMM_AUTH_ACCEPT, &d->flags)) {
1806                         rfcomm_dlc_clear_timer(d);
1807                         if (d->out) {
1808                                 rfcomm_send_pn(s, 1, d);
1809                                 rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
1810                         } else {
1811                                 if (d->defer_setup) {
1812                                         set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1813                                         rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1814
1815                                         rfcomm_dlc_lock(d);
1816                                         d->state = BT_CONNECT2;
1817                                         d->state_change(d, 0);
1818                                         rfcomm_dlc_unlock(d);
1819                                 } else
1820                                         rfcomm_dlc_accept(d);
1821                         }
1822                         continue;
1823                 } else if (test_and_clear_bit(RFCOMM_AUTH_REJECT, &d->flags)) {
1824                         rfcomm_dlc_clear_timer(d);
1825                         if (!d->out)
1826                                 rfcomm_send_dm(s, d->dlci);
1827                         else
1828                                 d->state = BT_CLOSED;
1829                         __rfcomm_dlc_close(d, ECONNREFUSED);
1830                         continue;
1831                 }
1832
1833                 if (test_bit(RFCOMM_SEC_PENDING, &d->flags))
1834                         continue;
1835
1836                 if (test_bit(RFCOMM_TX_THROTTLED, &s->flags))
1837                         continue;
1838
1839                 if ((d->state == BT_CONNECTED || d->state == BT_DISCONN) &&
1840                                                 d->mscex == RFCOMM_MSCEX_OK)
1841                         rfcomm_process_tx(d);
1842         }
1843 }
1844
1845 static inline void rfcomm_process_rx(struct rfcomm_session *s)
1846 {
1847         struct socket *sock = s->sock;
1848         struct sock *sk = sock->sk;
1849         struct sk_buff *skb;
1850
1851         BT_DBG("session %p state %ld qlen %d", s, s->state, skb_queue_len(&sk->sk_receive_queue));
1852
1853         /* Get data directly from socket receive queue without copying it. */
1854         while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
1855                 skb_orphan(skb);
1856                 if (!skb_linearize(skb))
1857                         rfcomm_recv_frame(s, skb);
1858                 else
1859                         kfree_skb(skb);
1860         }
1861
1862         if (sk->sk_state == BT_CLOSED) {
1863                 if (!s->initiator)
1864                         rfcomm_session_put(s);
1865
1866                 rfcomm_session_close(s, sk->sk_err);
1867         }
1868 }
1869
1870 static inline void rfcomm_accept_connection(struct rfcomm_session *s)
1871 {
1872         struct socket *sock = s->sock, *nsock;
1873         int err;
1874
1875         /* Fast check for a new connection.
1876          * Avoids unnesesary socket allocations. */
1877         if (list_empty(&bt_sk(sock->sk)->accept_q))
1878                 return;
1879
1880         BT_DBG("session %p", s);
1881
1882         err = kernel_accept(sock, &nsock, O_NONBLOCK);
1883         if (err < 0)
1884                 return;
1885
1886         /* Set our callbacks */
1887         nsock->sk->sk_data_ready   = rfcomm_l2data_ready;
1888         nsock->sk->sk_state_change = rfcomm_l2state_change;
1889
1890         s = rfcomm_session_add(nsock, BT_OPEN);
1891         if (s) {
1892                 rfcomm_session_hold(s);
1893
1894                 /* We should adjust MTU on incoming sessions.
1895                  * L2CAP MTU minus UIH header and FCS. */
1896                 s->mtu = min(l2cap_pi(nsock->sk)->chan->omtu,
1897                                 l2cap_pi(nsock->sk)->chan->imtu) - 5;
1898
1899                 rfcomm_schedule();
1900         } else
1901                 sock_release(nsock);
1902 }
1903
1904 static inline void rfcomm_check_connection(struct rfcomm_session *s)
1905 {
1906         struct sock *sk = s->sock->sk;
1907
1908         BT_DBG("%p state %ld", s, s->state);
1909
1910         switch (sk->sk_state) {
1911         case BT_CONNECTED:
1912                 s->state = BT_CONNECT;
1913
1914                 /* We can adjust MTU on outgoing sessions.
1915                  * L2CAP MTU minus UIH header and FCS. */
1916                 s->mtu = min(l2cap_pi(sk)->chan->omtu, l2cap_pi(sk)->chan->imtu) - 5;
1917
1918                 rfcomm_send_sabm(s, 0);
1919                 break;
1920
1921         case BT_CLOSED:
1922                 s->state = BT_CLOSED;
1923                 rfcomm_session_close(s, sk->sk_err);
1924                 break;
1925         }
1926 }
1927
1928 static inline void rfcomm_process_sessions(void)
1929 {
1930         struct list_head *p, *n;
1931
1932         rfcomm_lock();
1933
1934         list_for_each_safe(p, n, &session_list) {
1935                 struct rfcomm_session *s;
1936                 s = list_entry(p, struct rfcomm_session, list);
1937
1938                 if (test_and_clear_bit(RFCOMM_TIMED_OUT, &s->flags)) {
1939                         s->state = BT_DISCONN;
1940                         rfcomm_send_disc(s, 0);
1941                         rfcomm_session_put(s);
1942                         continue;
1943                 }
1944
1945                 if (s->state == BT_LISTEN) {
1946                         rfcomm_accept_connection(s);
1947                         continue;
1948                 }
1949
1950                 rfcomm_session_hold(s);
1951
1952                 switch (s->state) {
1953                 case BT_BOUND:
1954                         rfcomm_check_connection(s);
1955                         break;
1956
1957                 default:
1958                         rfcomm_process_rx(s);
1959                         break;
1960                 }
1961
1962                 rfcomm_process_dlcs(s);
1963
1964                 rfcomm_session_put(s);
1965         }
1966
1967         rfcomm_unlock();
1968 }
1969
1970 static int rfcomm_add_listener(bdaddr_t *ba)
1971 {
1972         struct sockaddr_l2 addr;
1973         struct socket *sock;
1974         struct sock *sk;
1975         struct rfcomm_session *s;
1976         int    err = 0;
1977
1978         /* Create socket */
1979         err = rfcomm_l2sock_create(&sock);
1980         if (err < 0) {
1981                 BT_ERR("Create socket failed %d", err);
1982                 return err;
1983         }
1984
1985         /* Bind socket */
1986         bacpy(&addr.l2_bdaddr, ba);
1987         addr.l2_family = AF_BLUETOOTH;
1988         addr.l2_psm    = cpu_to_le16(RFCOMM_PSM);
1989         addr.l2_cid    = 0;
1990         err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
1991         if (err < 0) {
1992                 BT_ERR("Bind failed %d", err);
1993                 goto failed;
1994         }
1995
1996         /* Set L2CAP options */
1997         sk = sock->sk;
1998         lock_sock(sk);
1999         l2cap_pi(sk)->chan->imtu = l2cap_mtu;
2000         release_sock(sk);
2001
2002         /* Start listening on the socket */
2003         err = kernel_listen(sock, 10);
2004         if (err) {
2005                 BT_ERR("Listen failed %d", err);
2006                 goto failed;
2007         }
2008
2009         /* Add listening session */
2010         s = rfcomm_session_add(sock, BT_LISTEN);
2011         if (!s)
2012                 goto failed;
2013
2014         rfcomm_session_hold(s);
2015         return 0;
2016 failed:
2017         sock_release(sock);
2018         return err;
2019 }
2020
2021 static void rfcomm_kill_listener(void)
2022 {
2023         struct rfcomm_session *s;
2024         struct list_head *p, *n;
2025
2026         BT_DBG("");
2027
2028         list_for_each_safe(p, n, &session_list) {
2029                 s = list_entry(p, struct rfcomm_session, list);
2030                 rfcomm_session_del(s);
2031         }
2032 }
2033
2034 static int rfcomm_run(void *unused)
2035 {
2036         BT_DBG("");
2037
2038         set_user_nice(current, -10);
2039
2040         rfcomm_add_listener(BDADDR_ANY);
2041
2042         while (1) {
2043                 set_current_state(TASK_INTERRUPTIBLE);
2044
2045                 if (kthread_should_stop())
2046                         break;
2047
2048                 /* Process stuff */
2049                 rfcomm_process_sessions();
2050
2051                 schedule();
2052         }
2053         __set_current_state(TASK_RUNNING);
2054
2055         rfcomm_kill_listener();
2056
2057         return 0;
2058 }
2059
2060 static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
2061 {
2062         struct rfcomm_session *s;
2063         struct rfcomm_dlc *d;
2064         struct list_head *p, *n;
2065
2066         BT_DBG("conn %p status 0x%02x encrypt 0x%02x", conn, status, encrypt);
2067
2068         s = rfcomm_session_get(&conn->hdev->bdaddr, &conn->dst);
2069         if (!s)
2070                 return;
2071
2072         rfcomm_session_hold(s);
2073
2074         list_for_each_safe(p, n, &s->dlcs) {
2075                 d = list_entry(p, struct rfcomm_dlc, list);
2076
2077                 if (test_and_clear_bit(RFCOMM_SEC_PENDING, &d->flags)) {
2078                         rfcomm_dlc_clear_timer(d);
2079                         if (status || encrypt == 0x00) {
2080                                 __rfcomm_dlc_close(d, ECONNREFUSED);
2081                                 continue;
2082                         }
2083                 }
2084
2085                 if (d->state == BT_CONNECTED && !status && encrypt == 0x00) {
2086                         if (d->sec_level == BT_SECURITY_MEDIUM) {
2087                                 set_bit(RFCOMM_SEC_PENDING, &d->flags);
2088                                 rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
2089                                 continue;
2090                         } else if (d->sec_level == BT_SECURITY_HIGH) {
2091                                 __rfcomm_dlc_close(d, ECONNREFUSED);
2092                                 continue;
2093                         }
2094                 }
2095
2096                 if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))
2097                         continue;
2098
2099                 if (!status && hci_conn_check_secure(conn, d->sec_level))
2100                         set_bit(RFCOMM_AUTH_ACCEPT, &d->flags);
2101                 else
2102                         set_bit(RFCOMM_AUTH_REJECT, &d->flags);
2103         }
2104
2105         rfcomm_session_put(s);
2106
2107         rfcomm_schedule();
2108 }
2109
2110 static struct hci_cb rfcomm_cb = {
2111         .name           = "RFCOMM",
2112         .security_cfm   = rfcomm_security_cfm
2113 };
2114
2115 static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
2116 {
2117         struct rfcomm_session *s;
2118         struct list_head *pp, *p;
2119
2120         rfcomm_lock();
2121
2122         list_for_each(p, &session_list) {
2123                 s = list_entry(p, struct rfcomm_session, list);
2124                 list_for_each(pp, &s->dlcs) {
2125                         struct sock *sk = s->sock->sk;
2126                         struct rfcomm_dlc *d = list_entry(pp, struct rfcomm_dlc, list);
2127
2128                         seq_printf(f, "%s %s %ld %d %d %d %d\n",
2129                                                 batostr(&bt_sk(sk)->src),
2130                                                 batostr(&bt_sk(sk)->dst),
2131                                                 d->state, d->dlci, d->mtu,
2132                                                 d->rx_credits, d->tx_credits);
2133                 }
2134         }
2135
2136         rfcomm_unlock();
2137
2138         return 0;
2139 }
2140
2141 static int rfcomm_dlc_debugfs_open(struct inode *inode, struct file *file)
2142 {
2143         return single_open(file, rfcomm_dlc_debugfs_show, inode->i_private);
2144 }
2145
2146 static const struct file_operations rfcomm_dlc_debugfs_fops = {
2147         .open           = rfcomm_dlc_debugfs_open,
2148         .read           = seq_read,
2149         .llseek         = seq_lseek,
2150         .release        = single_release,
2151 };
2152
2153 static struct dentry *rfcomm_dlc_debugfs;
2154
2155 /* ---- Initialization ---- */
2156 static int __init rfcomm_init(void)
2157 {
2158         int err;
2159
2160         hci_register_cb(&rfcomm_cb);
2161
2162         rfcomm_thread = kthread_run(rfcomm_run, NULL, "krfcommd");
2163         if (IS_ERR(rfcomm_thread)) {
2164                 err = PTR_ERR(rfcomm_thread);
2165                 goto unregister;
2166         }
2167
2168         if (bt_debugfs) {
2169                 rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
2170                                 bt_debugfs, NULL, &rfcomm_dlc_debugfs_fops);
2171                 if (!rfcomm_dlc_debugfs)
2172                         BT_ERR("Failed to create RFCOMM debug file");
2173         }
2174
2175         err = rfcomm_init_ttys();
2176         if (err < 0)
2177                 goto stop;
2178
2179         err = rfcomm_init_sockets();
2180         if (err < 0)
2181                 goto cleanup;
2182
2183         BT_INFO("RFCOMM ver %s", VERSION);
2184
2185         return 0;
2186
2187 cleanup:
2188         rfcomm_cleanup_ttys();
2189
2190 stop:
2191         kthread_stop(rfcomm_thread);
2192
2193 unregister:
2194         hci_unregister_cb(&rfcomm_cb);
2195
2196         return err;
2197 }
2198
2199 static void __exit rfcomm_exit(void)
2200 {
2201         debugfs_remove(rfcomm_dlc_debugfs);
2202
2203         hci_unregister_cb(&rfcomm_cb);
2204
2205         kthread_stop(rfcomm_thread);
2206
2207         rfcomm_cleanup_ttys();
2208
2209         rfcomm_cleanup_sockets();
2210 }
2211
2212 module_init(rfcomm_init);
2213 module_exit(rfcomm_exit);
2214
2215 module_param(disable_cfc, bool, 0644);
2216 MODULE_PARM_DESC(disable_cfc, "Disable credit based flow control");
2217
2218 module_param(channel_mtu, int, 0644);
2219 MODULE_PARM_DESC(channel_mtu, "Default MTU for the RFCOMM channel");
2220
2221 module_param(l2cap_mtu, uint, 0644);
2222 MODULE_PARM_DESC(l2cap_mtu, "Default MTU for the L2CAP connection");
2223
2224 module_param(l2cap_ertm, bool, 0644);
2225 MODULE_PARM_DESC(l2cap_ertm, "Use L2CAP ERTM mode for connection");
2226
2227 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
2228 MODULE_DESCRIPTION("Bluetooth RFCOMM ver " VERSION);
2229 MODULE_VERSION(VERSION);
2230 MODULE_LICENSE("GPL");
2231 MODULE_ALIAS("bt-proto-3");