sys/netbt/rfcomm_dlc.c

   1 /* $OpenBSD: src/sys/netbt/rfcomm_dlc.c,v 1.2 2008/02/24 21:34:48 uwe Exp $ */
   2 /* $NetBSD: rfcomm_dlc.c,v 1.4 2007/11/03 17:20:17 plunky Exp $ */
   3
   4 /*-
   5  * Copyright (c) 2006 Itronix Inc.
   6  * All rights reserved.
   7  *
   8  * Written by Iain Hibbert for Itronix Inc.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. The name of Itronix Inc. may not be used to endorse
  19  *    or promote products derived from this software without specific
  20  *    prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
  26  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  27  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  29  * ON ANY THEORY OF LIABILITY, WHETHER IN
  30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32  * POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/kernel.h>
  37 #include <sys/malloc.h>
  38 #include <sys/mbuf.h>
  39 #include <sys/proc.h>
  40 #include <sys/systm.h>
  41 #include <sys/endian.h>
  42
  43 #include <netbt/bluetooth.h>
  44 #include <netbt/hci.h>
  45 #include <netbt/l2cap.h>
  46 #include <netbt/rfcomm.h>
  47
  48 /*
  49  * rfcomm_dlc_lookup(rfcomm_session, dlci)
  50  *
  51  * Find DLC on session with matching dlci
  52  */
  53 struct rfcomm_dlc *
  54 rfcomm_dlc_lookup(struct rfcomm_session *rs, int dlci)
  55 {
  56         struct rfcomm_dlc *dlc;
  57
  58         LIST_FOREACH(dlc, &rs->rs_dlcs, rd_next) {
  59                 if (dlc->rd_dlci == dlci)
  60                         break;
  61         }
  62
  63         return dlc;
  64 }
  65
  66 /*
  67  * rfcomm_dlc_newconn(rfcomm_session, dlci)
  68  *
  69  * handle a new dlc request (since its called from a couple of places)
  70  */
  71 struct rfcomm_dlc *
  72 rfcomm_dlc_newconn(struct rfcomm_session *rs, int dlci)
  73 {
  74         struct rfcomm_session *ls;
  75         struct rfcomm_dlc *new, *dlc, *any, *best;
  76         struct sockaddr_bt laddr, raddr, addr;
  77         int chan;
  78
  79         /*
  80          * Search amongst the listening DLC community for the best match for
  81          * address & channel. We keep listening DLC's hanging on listening
  82          * sessions in a last first order, so scan the entire bunch and keep
  83          * a note of the best address and BDADDR_ANY matches in order to find
  84          * the oldest and most specific match.
  85          */
  86         l2cap_sockaddr(rs->rs_l2cap, &laddr);
  87         l2cap_peeraddr(rs->rs_l2cap, &raddr);
  88         chan = RFCOMM_CHANNEL(dlci);
  89         new = NULL;
  90
  91         any = best = NULL;
  92         LIST_FOREACH(ls, &rfcomm_session_listen, rs_next) {
  93                 l2cap_sockaddr(ls->rs_l2cap, &addr);
  94
  95                 if (addr.bt_psm != laddr.bt_psm)
  96                         continue;
  97
  98                 if (bdaddr_same(&laddr.bt_bdaddr, &addr.bt_bdaddr)) {
  99                         LIST_FOREACH(dlc, &ls->rs_dlcs, rd_next) {
 100                                 if (dlc->rd_laddr.bt_channel == chan)
 101                                         best = dlc;
 102                         }
 103                 }
 104
 105                 if (bdaddr_any(&addr.bt_bdaddr)) {
 106                         LIST_FOREACH(dlc, &ls->rs_dlcs, rd_next) {
 107                                 if (dlc->rd_laddr.bt_channel == chan)
 108                                         any = dlc;
 109                         }
 110                 }
 111         }
 112
 113         dlc = best ? best : any;
 114
 115         /* XXX
 116          * Note that if this fails, we could have missed a chance to open
 117          * a connection - really need to rewrite the strategy for storing
 118          * listening DLC's so all can be checked in turn..
 119          */
 120         if (dlc != NULL)
 121                 new = (*dlc->rd_proto->newconn)(dlc->rd_upper, &laddr, &raddr);
 122
 123         if (new == NULL) {
 124                 rfcomm_session_send_frame(rs, RFCOMM_FRAME_DM, dlci);
 125                 return NULL;
 126         }
 127
 128         new->rd_dlci = dlci;
 129         new->rd_mtu = rfcomm_mtu_default;
 130         new->rd_mode = dlc->rd_mode;
 131
 132         memcpy(&new->rd_laddr, &laddr, sizeof(struct sockaddr_bt));
 133         new->rd_laddr.bt_channel = chan;
 134
 135         memcpy(&new->rd_raddr, &raddr, sizeof(struct sockaddr_bt));
 136         new->rd_raddr.bt_channel = chan;
 137
 138         new->rd_session = rs;
 139         new->rd_state = RFCOMM_DLC_WAIT_CONNECT;
 140         LIST_INSERT_HEAD(&rs->rs_dlcs, new, rd_next);
 141
 142         return new;
 143 }
 144
 145 /*
 146  * rfcomm_dlc_close(dlc, error)
 147  *
 148  * detach DLC from session and clean up
 149  */
 150 void
 151 rfcomm_dlc_close(struct rfcomm_dlc *dlc, int err)
 152 {
 153         struct rfcomm_session *rs;
 154         struct rfcomm_credit *credit;
 155
 156         KKASSERT(dlc->rd_state != RFCOMM_DLC_CLOSED);
 157
 158         /* Clear credit history */
 159         rs = dlc->rd_session;
 160         STAILQ_FOREACH(credit, &rs->rs_credits, rc_next)
 161                 if (credit->rc_dlc == dlc)
 162                         credit->rc_dlc = NULL;
 163
 164         callout_stop(&dlc->rd_timeout);
 165
 166         LIST_REMOVE(dlc, rd_next);
 167         dlc->rd_session = NULL;
 168         dlc->rd_state = RFCOMM_DLC_CLOSED;
 169
 170         (*dlc->rd_proto->disconnected)(dlc->rd_upper, err);
 171
 172         /*
 173          * It is the responsibility of the party who sends the last
 174          * DISC(dlci) to disconnect the session, but we will schedule
 175          * an expiry just in case that doesnt happen..
 176          */
 177         if (LIST_EMPTY(&rs->rs_dlcs)) {
 178                 if (rs->rs_state == RFCOMM_SESSION_LISTEN)
 179                         rfcomm_session_free(rs);
 180                 else
 181                         callout_reset(&rs->rs_timeout, rfcomm_ack_timeout * hz,
 182                             rfcomm_session_timeout, rs);
 183         }
 184 }
 185
 186 /*
 187  * rfcomm_dlc_timeout(dlc)
 188  *
 189  * DLC timeout function is schedUled when we sent any of SABM,
 190  * DISC, MCC_MSC, or MCC_PN and should be cancelled when we get
 191  * the relevant response. There is nothing to do but shut this
 192  * DLC down.
 193  */
 194 void
 195 rfcomm_dlc_timeout(void *arg)
 196 {
 197         struct rfcomm_dlc *dlc = arg;
 198
 199         crit_enter();
 200
 201         if (dlc->rd_state != RFCOMM_DLC_CLOSED)
 202                 rfcomm_dlc_close(dlc, ETIMEDOUT);
 203         else if (dlc->rd_flags & RFCOMM_DLC_DETACH)
 204                 kfree(dlc, M_BLUETOOTH);
 205
 206         crit_exit();
 207 }
 208
 209 /*
 210  * rfcomm_dlc_setmode(rfcomm_dlc)
 211  *
 212  * Set link mode for DLC.  This is only called when the session is
 213  * already open, so we don't need to worry about any previous mode
 214  * settings.
 215  */
 216 int
 217 rfcomm_dlc_setmode(struct rfcomm_dlc *dlc)
 218 {
 219         int mode = 0;
 220
 221         KKASSERT(dlc->rd_session != NULL);
 222         KKASSERT(dlc->rd_session->rs_state == RFCOMM_SESSION_OPEN);
 223
 224         DPRINTF("dlci %d, auth %s, encrypt %s, secure %s\n", dlc->rd_dlci,
 225                 (dlc->rd_mode & RFCOMM_LM_AUTH ? "yes" : "no"),
 226                 (dlc->rd_mode & RFCOMM_LM_ENCRYPT ? "yes" : "no"),
 227                 (dlc->rd_mode & RFCOMM_LM_SECURE ? "yes" : "no"));
 228
 229         if (dlc->rd_mode & RFCOMM_LM_AUTH)
 230                 mode |= L2CAP_LM_AUTH;
 231
 232         if (dlc->rd_mode & RFCOMM_LM_ENCRYPT)
 233                 mode |= L2CAP_LM_ENCRYPT;
 234
 235         if (dlc->rd_mode & RFCOMM_LM_SECURE)
 236                 mode |= L2CAP_LM_SECURE;
 237
 238         return l2cap_setopt(dlc->rd_session->rs_l2cap, SO_L2CAP_LM, &mode);
 239 }
 240
 241 /*
 242  * rfcomm_dlc_connect(rfcomm_dlc)
 243  *
 244  * initiate DLC connection (session is already connected)
 245  */
 246 int
 247 rfcomm_dlc_connect(struct rfcomm_dlc *dlc)
 248 {
 249         struct rfcomm_mcc_pn pn;
 250         int err = 0;
 251
 252         KKASSERT(dlc->rd_session != NULL);
 253         KKASSERT(dlc->rd_session->rs_state == RFCOMM_SESSION_OPEN);
 254         KKASSERT(dlc->rd_state == RFCOMM_DLC_WAIT_SESSION);
 255
 256         /*
 257          * If we have not already sent a PN on the session, we must send
 258          * a PN to negotiate Credit Flow Control, and this setting will
 259          * apply to all future connections for this session. We ask for
 260          * this every time, in order to establish initial credits.
 261          */
 262         memset(&pn, 0, sizeof(pn));
 263         pn.dlci = dlc->rd_dlci;
 264         pn.priority = dlc->rd_dlci | 0x07;
 265         pn.mtu = htole16(dlc->rd_mtu);
 266
 267         pn.flow_control = 0xf0;
 268         dlc->rd_rxcred = (dlc->rd_rxsize / dlc->rd_mtu);
 269         dlc->rd_rxcred = min(dlc->rd_rxcred, RFCOMM_CREDITS_DEFAULT);
 270         pn.credits = dlc->rd_rxcred;
 271
 272         err = rfcomm_session_send_mcc(dlc->rd_session, 1,
 273                                         RFCOMM_MCC_PN, &pn, sizeof(pn));
 274         if (err)
 275                 return err;
 276
 277         dlc->rd_state = RFCOMM_DLC_WAIT_CONNECT;
 278         callout_reset(&dlc->rd_timeout, rfcomm_mcc_timeout * hz,
 279             rfcomm_dlc_timeout, dlc);
 280         return 0;
 281 }
 282
 283 /*
 284  * rfcomm_dlc_open(rfcomm_dlc)
 285  *
 286  * send "Modem Status Command" and mark DLC as open.
 287  */
 288 int
 289 rfcomm_dlc_open(struct rfcomm_dlc *dlc)
 290 {
 291         struct rfcomm_mcc_msc msc;
 292         int err;
 293
 294         KKASSERT(dlc->rd_session != NULL);
 295         KKASSERT(dlc->rd_session->rs_state == RFCOMM_SESSION_OPEN);
 296
 297         memset(&msc, 0, sizeof(msc));
 298         msc.address = RFCOMM_MKADDRESS(1, dlc->rd_dlci);
 299         msc.modem = dlc->rd_lmodem & 0xfe;      /* EA = 0 */
 300         msc.brk =       0x00       | 0x01;      /* EA = 1 */
 301
 302         err = rfcomm_session_send_mcc(dlc->rd_session, 1,
 303                                 RFCOMM_MCC_MSC, &msc, sizeof(msc));
 304         if (err)
 305                 return err;
 306
 307         callout_reset(&dlc->rd_timeout, rfcomm_mcc_timeout * hz,
 308             rfcomm_dlc_timeout, dlc);
 309
 310         dlc->rd_state = RFCOMM_DLC_OPEN;
 311         (*dlc->rd_proto->connected)(dlc->rd_upper);
 312
 313         return 0;
 314 }
 315
 316 /*
 317  * rfcomm_dlc_start(rfcomm_dlc)
 318  *
 319  * Start sending data (and/or credits) for DLC. Our strategy is to
 320  * send anything we can down to the l2cap layer. When credits run
 321  * out, data will naturally bunch up. When not using credit flow
 322  * control, we limit the number of packets we have pending to reduce
 323  * flow control lag.
 324  * We should deal with channel priority somehow.
 325  */
 326 void
 327 rfcomm_dlc_start(struct rfcomm_dlc *dlc)
 328 {
 329         struct rfcomm_session *rs = dlc->rd_session;
 330         struct mbuf *m;
 331         int len, credits;
 332
 333         KKASSERT(rs != NULL);
 334         KKASSERT(rs->rs_state == RFCOMM_SESSION_OPEN);
 335         KKASSERT(dlc->rd_state == RFCOMM_DLC_OPEN);
 336
 337         for (;;) {
 338                 credits = 0;
 339                 len = dlc->rd_mtu;
 340                 if (rs->rs_flags & RFCOMM_SESSION_CFC) {
 341                         credits = (dlc->rd_rxsize / dlc->rd_mtu);
 342                         credits -= dlc->rd_rxcred;
 343                         credits = min(credits, RFCOMM_CREDITS_MAX);
 344
 345                         if (credits > 0)
 346                                 len--;
 347
 348                         if (dlc->rd_txcred == 0)
 349                                 len = 0;
 350                 } else {
 351                         if (rs->rs_flags & RFCOMM_SESSION_RFC)
 352                                 break;
 353
 354                         if (dlc->rd_rmodem & RFCOMM_MSC_FC)
 355                                 break;
 356
 357                         if (dlc->rd_pending > RFCOMM_CREDITS_DEFAULT)
 358                                 break;
 359                 }
 360
 361                 if (dlc->rd_txbuf == NULL)
 362                         len = 0;
 363
 364                 if (len == 0) {
 365                         if (credits == 0)
 366                                 break;
 367
 368                         /*
 369                          * No need to send small numbers of credits on their
 370                          * own unless the other end hasn't many left.
 371                          */
 372                         if (credits < RFCOMM_CREDITS_DEFAULT
 373                             && dlc->rd_rxcred > RFCOMM_CREDITS_DEFAULT)
 374                                 break;
 375
 376                         m = NULL;
 377                 } else {
 378                         /*
 379                          * take what data we can from (front of) txbuf
 380                          */
 381                         m = dlc->rd_txbuf;
 382                         if (len < m->m_pkthdr.len) {
 383                                 dlc->rd_txbuf = m_split(m, len, M_NOWAIT);
 384                                 if (dlc->rd_txbuf == NULL) {
 385                                         dlc->rd_txbuf = m;
 386                                         break;
 387                                 }
 388                         } else {
 389                                 dlc->rd_txbuf = NULL;
 390                                 len = m->m_pkthdr.len;
 391                         }
 392                 }
 393
 394                 DPRINTFN(10, "dlci %d send %d bytes, %d credits, rxcred = %d\n",
 395                         dlc->rd_dlci, len, credits, dlc->rd_rxcred);
 396
 397                 if (rfcomm_session_send_uih(rs, dlc, credits, m)) {
 398                         kprintf("%s: lost %d bytes on DLCI %d\n",
 399                                 __func__, len, dlc->rd_dlci);
 400
 401                         break;
 402                 }
 403
 404                 dlc->rd_pending++;
 405
 406                 if (rs->rs_flags & RFCOMM_SESSION_CFC) {
 407                         if (len > 0)
 408                                 dlc->rd_txcred--;
 409
 410                         if (credits > 0)
 411                                 dlc->rd_rxcred += credits;
 412                 }
 413         }
 414 }