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      1 /******************************************************************************
      2  *
      3  *  Copyright 1999-2012 Broadcom Corporation
      4  *
      5  *  Licensed under the Apache License, Version 2.0 (the "License");
      6  *  you may not use this file except in compliance with the License.
      7  *  You may obtain a copy of the License at:
      8  *
      9  *  http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  *  Unless required by applicable law or agreed to in writing, software
     12  *  distributed under the License is distributed on an "AS IS" BASIS,
     13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  *  See the License for the specific language governing permissions and
     15  *  limitations under the License.
     16  *
     17  ******************************************************************************/
     18 
     19 /******************************************************************************
     20  *
     21  *  This module contains functions for port emulation entity and RFCOMM
     22  *  communications
     23  *
     24  ******************************************************************************/
     25 #include <base/logging.h>
     26 #include <string.h>
     27 
     28 #include "osi/include/mutex.h"
     29 #include "osi/include/osi.h"
     30 
     31 #include "bt_common.h"
     32 #include "bt_target.h"
     33 #include "bt_utils.h"
     34 #include "btm_api.h"
     35 #include "btm_int.h"
     36 #include "port_api.h"
     37 #include "port_int.h"
     38 #include "rfc_int.h"
     39 #include "rfcdefs.h"
     40 
     41 /*
     42  * Local function definitions
     43 */
     44 uint32_t port_rfc_send_tx_data(tPORT* p_port);
     45 void port_rfc_closed(tPORT* p_port, uint8_t res);
     46 void port_get_credits(tPORT* p_port, uint8_t k);
     47 
     48 /*******************************************************************************
     49  *
     50  * Function         port_open_continue
     51  *
     52  * Description      This function is called after security manager completes
     53  *                  required security checks.
     54  *
     55  * Returns          void
     56  *
     57  ******************************************************************************/
     58 int port_open_continue(tPORT* p_port) {
     59   tRFC_MCB* p_mcb;
     60 
     61   RFCOMM_TRACE_EVENT("port_open_continue, p_port:%p", p_port);
     62 
     63   /* Check if multiplexer channel has already been established */
     64   p_mcb = rfc_alloc_multiplexer_channel(p_port->bd_addr, true);
     65   if (p_mcb == NULL) {
     66     RFCOMM_TRACE_WARNING("port_open_continue no mx channel");
     67     port_release_port(p_port);
     68     return (PORT_NO_RESOURCES);
     69   }
     70 
     71   p_port->rfc.p_mcb = p_mcb;
     72 
     73   p_mcb->port_inx[p_port->dlci] = p_port->inx;
     74 
     75   /* Connection is up and we know local and remote features, select MTU */
     76   port_select_mtu(p_port);
     77 
     78   if (p_mcb->state == RFC_MX_STATE_CONNECTED) {
     79     RFCOMM_ParNegReq(p_mcb, p_port->dlci, p_port->mtu);
     80   } else if ((p_mcb->state == RFC_MX_STATE_IDLE) ||
     81              (p_mcb->state == RFC_MX_STATE_DISC_WAIT_UA)) {
     82     /* In RFC_MX_STATE_IDLE state, MX state machine will create connection */
     83     /* In RFC_MX_STATE_DISC_WAIT_UA state, MX state machine will recreate
     84      * connection */
     85     /*    after disconnecting is completed */
     86     RFCOMM_StartReq(p_mcb);
     87   } else {
     88     /* MX state machine ignores RFC_MX_EVENT_START_REQ in these states */
     89     /* When it enters RFC_MX_STATE_CONNECTED, it will check any openning ports
     90      */
     91     RFCOMM_TRACE_DEBUG(
     92         "port_open_continue: mx state(%d) mx channel is openning",
     93         p_mcb->state);
     94   }
     95   return (PORT_SUCCESS);
     96 }
     97 
     98 /*******************************************************************************
     99  *
    100  * Function         port_start_control
    101  *
    102  * Description      This function is called in the BTU_TASK context to
    103  *                  send control information
    104  *
    105  * Returns          void
    106  *
    107  ******************************************************************************/
    108 void port_start_control(tPORT* p_port) {
    109   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    110 
    111   if (p_mcb == NULL) return;
    112 
    113   RFCOMM_ControlReq(p_mcb, p_port->dlci, &p_port->local_ctrl);
    114 }
    115 
    116 /*******************************************************************************
    117  *
    118  * Function         port_start_par_neg
    119  *
    120  * Description      This function is called in the BTU_TASK context to
    121  *                  send configuration information
    122  *
    123  * Returns          void
    124  *
    125  ******************************************************************************/
    126 void port_start_par_neg(tPORT* p_port) {
    127   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    128 
    129   if (p_mcb == NULL) return;
    130 
    131   RFCOMM_PortNegReq(p_mcb, p_port->dlci, &p_port->user_port_pars);
    132 }
    133 
    134 /*******************************************************************************
    135  *
    136  * Function         port_start_close
    137  *
    138  * Description      This function is called in the BTU_TASK context to
    139  *                  release DLC
    140  *
    141  * Returns          void
    142  *
    143  ******************************************************************************/
    144 void port_start_close(tPORT* p_port) {
    145   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    146   uint8_t old_signals;
    147   uint32_t events = 0;
    148 
    149   /* At first indicate to the user that signals on the connection were dropped
    150    */
    151   p_port->line_status |= LINE_STATUS_FAILED;
    152   old_signals = p_port->peer_ctrl.modem_signal;
    153 
    154   p_port->peer_ctrl.modem_signal &=
    155       ~(PORT_DTRDSR_ON | PORT_CTSRTS_ON | PORT_DCD_ON);
    156 
    157   events |= port_get_signal_changes(p_port, old_signals,
    158                                     p_port->peer_ctrl.modem_signal);
    159 
    160   if (p_port->ev_mask & PORT_EV_CONNECT_ERR) events |= PORT_EV_CONNECT_ERR;
    161 
    162   if (p_port->ev_mask & PORT_EV_ERR) events |= PORT_EV_ERR;
    163 
    164   if ((p_port->p_callback != NULL) && events)
    165     p_port->p_callback(events, p_port->inx);
    166 
    167   /* Check if RFCOMM side has been closed while the message was queued */
    168   if ((p_mcb == NULL) || (p_port->rfc.state == RFC_STATE_CLOSED)) {
    169     /* Call management callback function before calling port_release_port() to
    170      * clear tPort */
    171     if (p_port->p_mgmt_callback)
    172       p_port->p_mgmt_callback(PORT_CLOSED, p_port->inx);
    173 
    174     port_release_port(p_port);
    175   } else {
    176     RFCOMM_DlcReleaseReq(p_mcb, p_port->dlci);
    177   }
    178 }
    179 
    180 /*******************************************************************************
    181  *
    182  * Function         PORT_StartCnf
    183  *
    184  * Description      This function is called from the RFCOMM layer when
    185  *                  establishing of the multiplexer channel is completed.
    186  *                  Continue establishing of the connection for all ports that
    187  *                  are in the OPENING state
    188  *
    189  ******************************************************************************/
    190 void PORT_StartCnf(tRFC_MCB* p_mcb, uint16_t result) {
    191   tPORT* p_port;
    192   int i;
    193   bool no_ports_up = true;
    194 
    195   RFCOMM_TRACE_EVENT("PORT_StartCnf result:%d", result);
    196 
    197   p_port = &rfc_cb.port.port[0];
    198   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    199     if (p_port->rfc.p_mcb == p_mcb) {
    200       no_ports_up = false;
    201 
    202       if (result == RFCOMM_SUCCESS)
    203         RFCOMM_ParNegReq(p_mcb, p_port->dlci, p_port->mtu);
    204       else {
    205         RFCOMM_TRACE_WARNING("PORT_StartCnf failed result:%d", result);
    206 
    207         /* Warning: result is also set to 4 when l2cap connection
    208            fails due to l2cap connect cnf (no_resources) */
    209         if (result == HCI_ERR_PAGE_TIMEOUT)
    210           p_port->error = PORT_PAGE_TIMEOUT;
    211         else
    212           p_port->error = PORT_START_FAILED;
    213 
    214         rfc_release_multiplexer_channel(p_mcb);
    215 
    216         /* Send event to the application */
    217         if (p_port->p_callback && (p_port->ev_mask & PORT_EV_CONNECT_ERR))
    218           (p_port->p_callback)(PORT_EV_CONNECT_ERR, p_port->inx);
    219 
    220         if (p_port->p_mgmt_callback)
    221           p_port->p_mgmt_callback(PORT_START_FAILED, p_port->inx);
    222 
    223         port_release_port(p_port);
    224       }
    225     }
    226   }
    227 
    228   /* There can be a situation when after starting connection, user closes the */
    229   /* port, we can catch it here to close multiplexor channel */
    230   if (no_ports_up) {
    231     rfc_check_mcb_active(p_mcb);
    232   }
    233 }
    234 
    235 /*******************************************************************************
    236  *
    237  * Function         PORT_StartInd
    238  *
    239  * Description      This function is called from the RFCOMM layer when
    240  *                  some peer device wants to establish a multiplexer
    241  *                  connection.  Check if there are any ports open with this
    242  *                  or not assigned multiplexer.
    243  *
    244  ******************************************************************************/
    245 void PORT_StartInd(tRFC_MCB* p_mcb) {
    246   tPORT* p_port;
    247   int i;
    248 
    249   RFCOMM_TRACE_EVENT("PORT_StartInd");
    250 
    251   p_port = &rfc_cb.port.port[0];
    252   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    253     if ((p_port->rfc.p_mcb == NULL) || (p_port->rfc.p_mcb == p_mcb)) {
    254       RFCOMM_TRACE_DEBUG(
    255           "PORT_StartInd, RFCOMM_StartRsp RFCOMM_SUCCESS: p_mcb:%p", p_mcb);
    256       RFCOMM_StartRsp(p_mcb, RFCOMM_SUCCESS);
    257       return;
    258     }
    259   }
    260   RFCOMM_StartRsp(p_mcb, RFCOMM_ERROR);
    261 }
    262 
    263 /*******************************************************************************
    264  *
    265  * Function         PORT_ParNegInd
    266  *
    267  * Description      This function is called from the RFCOMM layer to change
    268  *                  DLCI parameters (currently only MTU is negotiated).
    269  *                  If can not find the port do not accept the request.
    270  *                  Otherwise save the MTU size supported by the peer.
    271  *
    272  ******************************************************************************/
    273 void PORT_ParNegInd(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu, uint8_t cl,
    274                     uint8_t k) {
    275   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    276   uint8_t our_cl;
    277   uint8_t our_k;
    278 
    279   RFCOMM_TRACE_EVENT("PORT_ParNegInd dlci:%d mtu:%d", dlci, mtu);
    280 
    281   if (!p_port) {
    282     /* This can be a first request for this port */
    283     p_port = port_find_dlci_port(dlci);
    284     if (!p_port) {
    285       LOG(ERROR) << __func__ << ": Disconnect RFCOMM, port not found, dlci="
    286                  << std::to_string(dlci) << ", p_mcb=" << p_mcb
    287                  << ", bd_addr=" << p_mcb->bd_addr;
    288       /* If the port cannot be opened, send a DM.  Per Errata 1205 */
    289       rfc_send_dm(p_mcb, dlci, false);
    290       /* check if this is the last port open, some headsets have
    291       problem, they don't disconnect if we send DM */
    292       rfc_check_mcb_active(p_mcb);
    293       return;
    294     }
    295     RFCOMM_TRACE_EVENT("%s: port_inx[dlci:%d]:%d->%d", __func__, dlci,
    296                        p_mcb->port_inx[dlci], p_port->inx);
    297     p_mcb->port_inx[dlci] = p_port->inx;
    298   }
    299 
    300   p_port->bd_addr = p_mcb->bd_addr;
    301 
    302   /* Connection is up and we know local and remote features, select MTU */
    303   port_select_mtu(p_port);
    304 
    305   p_port->rfc.p_mcb = p_mcb;
    306   p_port->mtu = (p_port->mtu < mtu) ? p_port->mtu : mtu;
    307   p_port->peer_mtu = p_port->mtu;
    308 
    309   /* Negotiate the flow control mechanism.  If flow control mechanism for */
    310   /* mux has not been set yet, set it now.  If either we or peer wants TS 07.10,
    311    */
    312   /* use that.  Otherwise both must want credit based, so use that. If flow is
    313    */
    314   /* already defined for this mux, we respond with that value. */
    315   if (p_mcb->flow == PORT_FC_UNDEFINED) {
    316     if ((PORT_FC_DEFAULT == PORT_FC_TS710) ||
    317         (cl == RFCOMM_PN_CONV_LAYER_TYPE_1)) {
    318       p_mcb->flow = PORT_FC_TS710;
    319     } else {
    320       p_mcb->flow = PORT_FC_CREDIT;
    321     }
    322   }
    323 
    324   /* Regardless of our flow control mechanism, if the PN cl is zero, we must */
    325   /* respond with zero.  "A responding implementation must set this field to 14
    326    */
    327   /* if (and only if) the PN request was 15."  This could happen if a PN is sent
    328    */
    329   /* after the DLCI is already established-- the PN in that case must have cl =
    330    * 0. */
    331   /* See RFCOMM spec 5.5.3 */
    332   if (cl == RFCOMM_PN_CONV_LAYER_TYPE_1) {
    333     our_cl = RFCOMM_PN_CONV_LAYER_TYPE_1;
    334     our_k = 0;
    335   } else if (p_mcb->flow == PORT_FC_CREDIT) {
    336     /* get credits */
    337     port_get_credits(p_port, k);
    338 
    339     /* Set convergence layer and number of credits (k) */
    340     our_cl = RFCOMM_PN_CONV_LAYER_CBFC_R;
    341     our_k = (p_port->credit_rx_max < RFCOMM_K_MAX) ? p_port->credit_rx_max
    342                                                    : RFCOMM_K_MAX;
    343     p_port->credit_rx = our_k;
    344   } else {
    345     /* must not be using credit based flow control; use TS 7.10 */
    346     our_cl = RFCOMM_PN_CONV_LAYER_TYPE_1;
    347     our_k = 0;
    348   }
    349   RFCOMM_ParNegRsp(p_mcb, dlci, p_port->mtu, our_cl, our_k);
    350 }
    351 
    352 /*******************************************************************************
    353  *
    354  * Function         PORT_ParNegCnf
    355  *
    356  * Description      This function is called from the RFCOMM layer to change
    357  *                  DLCI parameters (currently only MTU is negotiated).
    358  *                  Save the MTU size supported by the peer.
    359  *                  If the confirmation is received during the port opening
    360  *                  procedure send EstablishRequest to continue.
    361  *
    362  ******************************************************************************/
    363 void PORT_ParNegCnf(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu, uint8_t cl,
    364                     uint8_t k) {
    365   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    366 
    367   RFCOMM_TRACE_EVENT("PORT_ParNegCnf dlci:%d mtu:%d cl: %d k: %d", dlci, mtu,
    368                      cl, k);
    369 
    370   if (!p_port) return;
    371 
    372   /* Flow control mechanism not set yet.  Negotiate flow control mechanism. */
    373   if (p_mcb->flow == PORT_FC_UNDEFINED) {
    374     /* Our stack is configured for TS07.10 and they responded with credit-based.
    375      */
    376     /* This is illegal-- negotiation fails. */
    377     if ((PORT_FC_DEFAULT == PORT_FC_TS710) &&
    378         (cl == RFCOMM_PN_CONV_LAYER_CBFC_R)) {
    379       RFCOMM_TRACE_WARNING("%s, negotiation fails, index=%d", __func__,
    380                            p_port->inx);
    381       rfc_send_disc(p_mcb, p_port->dlci);
    382       rfc_port_closed(p_port);
    383       return;
    384     }
    385     /* Our stack is configured for credit-based and they responded with
    386        credit-based. */
    387     else if (cl == RFCOMM_PN_CONV_LAYER_CBFC_R) {
    388       p_mcb->flow = PORT_FC_CREDIT;
    389     }
    390     /* They responded with any other value.  Treat this as negotiation to
    391        TS07.10. */
    392     else {
    393       p_mcb->flow = PORT_FC_TS710;
    394     }
    395   }
    396   /* If mux flow control mechanism set, we honor that setting regardless of */
    397   /* the CL value in their response.  This allows us to gracefully accept any */
    398   /* illegal PN negotiation scenarios. */
    399 
    400   p_port->mtu = (p_port->mtu < mtu) ? p_port->mtu : mtu;
    401   p_port->peer_mtu = p_port->mtu;
    402 
    403   if (p_mcb->flow == PORT_FC_CREDIT) {
    404     port_get_credits(p_port, k);
    405   }
    406 
    407   if (p_port->state == PORT_STATE_OPENING)
    408     RFCOMM_DlcEstablishReq(p_mcb, p_port->dlci, p_port->mtu);
    409 }
    410 
    411 /*******************************************************************************
    412  *
    413  * Function         PORT_DlcEstablishInd
    414  *
    415  * Description      This function is called from the RFCOMM layer when peer
    416  *                  device wants to establish a new DLC.  If this is not the
    417  *                  first message in the establishment procedure port_handle
    418  *                  has a handle to the port control block otherwise the control
    419  *                  block should be found based on the muliplexer channel and
    420  *                  dlci.  The block should be allocated allocated before
    421  *                  meaning that application already made open.
    422  *
    423  ******************************************************************************/
    424 void PORT_DlcEstablishInd(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu) {
    425   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    426 
    427   RFCOMM_TRACE_DEBUG(
    428       "PORT_DlcEstablishInd p_mcb:%p, dlci:%d mtu:%di, p_port:%p", p_mcb, dlci,
    429       mtu, p_port);
    430   VLOG(1) << __func__ << " p_mcb addr:" << p_mcb->bd_addr;
    431 
    432   if (!p_port) {
    433     /* This can be a first request for this port */
    434     p_port = port_find_dlci_port(dlci);
    435     if (!p_port) {
    436       RFCOMM_DlcEstablishRsp(p_mcb, dlci, 0, RFCOMM_ERROR);
    437       return;
    438     }
    439     p_mcb->port_inx[dlci] = p_port->inx;
    440   }
    441 
    442   /* If L2CAP's mtu less then RFCOMM's take it */
    443   if (mtu && (mtu < p_port->peer_mtu)) p_port->peer_mtu = mtu;
    444 
    445   /* If there was an inactivity timer running for MCB stop it */
    446   rfc_timer_stop(p_mcb);
    447 
    448   RFCOMM_DlcEstablishRsp(p_mcb, dlci, p_port->mtu, RFCOMM_SUCCESS);
    449 
    450   /* This is the server side.  If application wants to know when connection */
    451   /* is established, thats the place */
    452   if (p_port->p_callback && (p_port->ev_mask & PORT_EV_CONNECTED))
    453     (p_port->p_callback)(PORT_EV_CONNECTED, p_port->inx);
    454 
    455   if (p_port->p_mgmt_callback)
    456     p_port->p_mgmt_callback(PORT_SUCCESS, p_port->inx);
    457 
    458   p_port->state = PORT_STATE_OPENED;
    459 }
    460 
    461 /*******************************************************************************
    462  *
    463  * Function         PORT_DlcEstablishCnf
    464  *
    465  * Description      This function is called from the RFCOMM layer when peer
    466  *                  acknowledges establish procedure (SABME/UA).  Send reply
    467  *                  to the user and set state to OPENED if result was
    468  *                  successfull.
    469  *
    470  ******************************************************************************/
    471 void PORT_DlcEstablishCnf(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu,
    472                           uint16_t result) {
    473   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    474 
    475   RFCOMM_TRACE_EVENT("PORT_DlcEstablishCnf dlci:%d mtu:%d result:%d", dlci, mtu,
    476                      result);
    477 
    478   if (!p_port) return;
    479 
    480   if (result != RFCOMM_SUCCESS) {
    481     p_port->error = PORT_START_FAILED;
    482     port_rfc_closed(p_port, PORT_START_FAILED);
    483     return;
    484   }
    485 
    486   /* If L2CAP's mtu less then RFCOMM's take it */
    487   if (mtu && (mtu < p_port->peer_mtu)) p_port->peer_mtu = mtu;
    488 
    489   /* If there was an inactivity timer running for MCB stop it */
    490   rfc_timer_stop(p_mcb);
    491 
    492   if (p_port->p_callback && (p_port->ev_mask & PORT_EV_CONNECTED))
    493     (p_port->p_callback)(PORT_EV_CONNECTED, p_port->inx);
    494 
    495   if (p_port->p_mgmt_callback)
    496     p_port->p_mgmt_callback(PORT_SUCCESS, p_port->inx);
    497 
    498   p_port->state = PORT_STATE_OPENED;
    499 
    500   /* RPN is required only if we want to tell DTE how the port should be opened
    501    */
    502   if ((p_port->uuid == UUID_SERVCLASS_DIALUP_NETWORKING) ||
    503       (p_port->uuid == UUID_SERVCLASS_FAX))
    504     RFCOMM_PortNegReq(p_port->rfc.p_mcb, p_port->dlci, NULL);
    505   else
    506     RFCOMM_ControlReq(p_port->rfc.p_mcb, p_port->dlci, &p_port->local_ctrl);
    507 }
    508 
    509 /*******************************************************************************
    510  *
    511  * Function         PORT_PortNegInd
    512  *
    513  * Description      This function is called from the RFCOMM layer when peer
    514  *                  device wants to set parameters of the port.  As per the spec
    515  *                  this message has to be sent before the first data packet
    516  *                  and can be sent before establish.  The block should be
    517  *                  allocated before meaning that application already made open.
    518  *
    519  ******************************************************************************/
    520 void PORT_PortNegInd(tRFC_MCB* p_mcb, uint8_t dlci, tPORT_STATE* p_pars,
    521                      uint16_t param_mask) {
    522   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    523 
    524   RFCOMM_TRACE_EVENT("PORT_PortNegInd");
    525 
    526   if (!p_port) {
    527     /* This can be a first request for this port */
    528     p_port = port_find_dlci_port(dlci);
    529     if (!p_port) {
    530       RFCOMM_PortNegRsp(p_mcb, dlci, p_pars, 0);
    531       return;
    532     }
    533     p_mcb->port_inx[dlci] = p_port->inx;
    534   }
    535 
    536   /* Check if the flow control is acceptable on local side */
    537   p_port->peer_port_pars = *p_pars;
    538   RFCOMM_PortNegRsp(p_mcb, dlci, p_pars, param_mask);
    539 }
    540 
    541 /*******************************************************************************
    542  *
    543  * Function         PORT_PortNegCnf
    544  *
    545  * Description      This function is called from the RFCOMM layer to change
    546  *                  state for the port.  Propagate change to the user.
    547  *
    548  ******************************************************************************/
    549 void PORT_PortNegCnf(tRFC_MCB* p_mcb, uint8_t dlci,
    550                      UNUSED_ATTR tPORT_STATE* p_pars, uint16_t result) {
    551   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    552 
    553   RFCOMM_TRACE_EVENT("PORT_PortNegCnf");
    554 
    555   if (!p_port) {
    556     RFCOMM_TRACE_WARNING("PORT_PortNegCnf no port");
    557     return;
    558   }
    559   /* Port negotiation failed. Drop the connection */
    560   if (result != RFCOMM_SUCCESS) {
    561     p_port->error = PORT_PORT_NEG_FAILED;
    562 
    563     RFCOMM_DlcReleaseReq(p_mcb, p_port->dlci);
    564 
    565     port_rfc_closed(p_port, PORT_PORT_NEG_FAILED);
    566     return;
    567   }
    568 
    569   if (!(p_port->port_ctrl & PORT_CTRL_REQ_SENT)) {
    570     RFCOMM_ControlReq(p_port->rfc.p_mcb, p_port->dlci, &p_port->local_ctrl);
    571   } else {
    572     RFCOMM_TRACE_WARNING("PORT_PortNegCnf Control Already sent");
    573   }
    574 }
    575 
    576 /*******************************************************************************
    577  *
    578  * Function         PORT_ControlInd
    579  *
    580  * Description      This function is called from the RFCOMM layer on the modem
    581  *                  signal change.  Propagate change to the user.
    582  *
    583  ******************************************************************************/
    584 void PORT_ControlInd(tRFC_MCB* p_mcb, uint8_t dlci, tPORT_CTRL* p_pars) {
    585   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    586   uint32_t event;
    587   uint8_t old_signals;
    588 
    589   RFCOMM_TRACE_EVENT("PORT_ControlInd");
    590 
    591   if (!p_port) return;
    592 
    593   old_signals = p_port->peer_ctrl.modem_signal;
    594 
    595   event = port_get_signal_changes(p_port, old_signals, p_pars->modem_signal);
    596 
    597   p_port->peer_ctrl = *p_pars;
    598 
    599   if (!(p_port->port_ctrl & PORT_CTRL_REQ_SENT))
    600     RFCOMM_ControlReq(p_port->rfc.p_mcb, p_port->dlci, &p_port->local_ctrl);
    601   else {
    602     /* If this is the first time we received control RFCOMM is connected */
    603     if (!(p_port->port_ctrl & PORT_CTRL_IND_RECEIVED)) {
    604       event |= (PORT_EV_CONNECTED & p_port->ev_mask);
    605     }
    606 
    607     if (p_port->port_ctrl & PORT_CTRL_REQ_CONFIRMED) {
    608       event |= port_rfc_send_tx_data(p_port);
    609     }
    610   }
    611 
    612   p_port->port_ctrl |= (PORT_CTRL_IND_RECEIVED | PORT_CTRL_IND_RESPONDED);
    613 
    614   if (p_pars->break_signal) event |= (PORT_EV_BREAK & p_port->ev_mask);
    615 
    616   /* execute call back function only if the application is registered for events
    617    */
    618   if (event && p_port->p_callback) (p_port->p_callback)(event, p_port->inx);
    619 
    620   RFCOMM_TRACE_EVENT(
    621       "PORT_ControlInd DTR_DSR : %d, RTS_CTS : %d, RI : %d, DCD : %d",
    622       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_DTRDSR) ? 1 : 0),
    623       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_RTSCTS) ? 1 : 0),
    624       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_RI) ? 1 : 0),
    625       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_DCD) ? 1 : 0));
    626 }
    627 
    628 /*******************************************************************************
    629  *
    630  * Function         PORT_ControlCnf
    631  *
    632  * Description      This function is called from the RFCOMM layer when
    633  *                  peer acknowleges change of the modem signals.
    634  *
    635  ******************************************************************************/
    636 void PORT_ControlCnf(tRFC_MCB* p_mcb, uint8_t dlci,
    637                      UNUSED_ATTR tPORT_CTRL* p_pars) {
    638   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    639   uint32_t event = 0;
    640 
    641   RFCOMM_TRACE_EVENT("PORT_ControlCnf");
    642 
    643   if (!p_port) return;
    644 
    645   if (!(p_port->port_ctrl & PORT_CTRL_REQ_CONFIRMED)) {
    646     p_port->port_ctrl |= PORT_CTRL_REQ_CONFIRMED;
    647 
    648     if (p_port->port_ctrl & PORT_CTRL_IND_RECEIVED)
    649       event = (p_port->ev_mask & PORT_EV_CONNECTED);
    650   }
    651 
    652   if (p_port->port_ctrl & PORT_CTRL_IND_RECEIVED) {
    653     event |= port_rfc_send_tx_data(p_port);
    654   }
    655 
    656   /* execute call back function only if the application is registered for events
    657    */
    658   if (event && p_port->p_callback) (p_port->p_callback)(event, p_port->inx);
    659 }
    660 
    661 /*******************************************************************************
    662  *
    663  * Function         PORT_LineStatusInd
    664  *
    665  * Description      This function is called from the RFCOMM layer when
    666  *                  peer indicates change in the line status
    667  *
    668  ******************************************************************************/
    669 void PORT_LineStatusInd(tRFC_MCB* p_mcb, uint8_t dlci, uint8_t line_status) {
    670   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    671   uint32_t event = 0;
    672 
    673   RFCOMM_TRACE_EVENT("PORT_LineStatusInd");
    674 
    675   if (!p_port) return;
    676 
    677   p_port->line_status |= line_status;
    678 
    679   if (line_status & PORT_ERR_OVERRUN) event |= PORT_EV_OVERRUN;
    680 
    681   if (line_status & PORT_ERR_BREAK) event |= PORT_EV_BREAK;
    682 
    683   if (line_status & ~(PORT_ERR_OVERRUN | PORT_ERR_BREAK)) event |= PORT_EV_ERR;
    684 
    685   if ((p_port->p_callback != NULL) && (p_port->ev_mask & event))
    686     p_port->p_callback((p_port->ev_mask & event), p_port->inx);
    687 }
    688 
    689 /*******************************************************************************
    690  *
    691  * Function         PORT_DlcReleaseInd
    692  *
    693  * Description      This function is called from the RFCOMM layer when
    694  *                  DLC connection is released.
    695  *
    696  ******************************************************************************/
    697 void PORT_DlcReleaseInd(tRFC_MCB* p_mcb, uint8_t dlci) {
    698   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    699 
    700   RFCOMM_TRACE_EVENT("PORT_DlcReleaseInd");
    701 
    702   if (!p_port) return;
    703 
    704   port_rfc_closed(p_port, PORT_CLOSED);
    705 }
    706 
    707 /*******************************************************************************
    708  *
    709  * Function         PORT_CloseInd
    710  *
    711  * Description      This function is called from the RFCOMM layer when
    712  *                  multiplexer connection is released.
    713  *
    714  ******************************************************************************/
    715 void PORT_CloseInd(tRFC_MCB* p_mcb) {
    716   tPORT* p_port;
    717   int i;
    718 
    719   RFCOMM_TRACE_EVENT("PORT_CloseInd");
    720 
    721   p_port = &rfc_cb.port.port[0];
    722   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    723     if (p_port->rfc.p_mcb == p_mcb) {
    724       port_rfc_closed(p_port, PORT_PEER_CONNECTION_FAILED);
    725     }
    726   }
    727   rfc_release_multiplexer_channel(p_mcb);
    728 }
    729 
    730 /*******************************************************************************
    731  *
    732  * Function         Port_TimeOutCloseMux
    733  *
    734  * Description      This function is called when RFCOMM timesout on a command
    735  *                  as a result multiplexer connection is closed.
    736  *
    737  ******************************************************************************/
    738 void Port_TimeOutCloseMux(tRFC_MCB* p_mcb) {
    739   tPORT* p_port;
    740   int i;
    741 
    742   RFCOMM_TRACE_EVENT("Port_TimeOutCloseMux");
    743 
    744   p_port = &rfc_cb.port.port[0];
    745   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    746     if (p_port->rfc.p_mcb == p_mcb) {
    747       port_rfc_closed(p_port, PORT_PEER_TIMEOUT);
    748     }
    749   }
    750 }
    751 
    752 /*******************************************************************************
    753  *
    754  * Function         PORT_DataInd
    755  *
    756  * Description      This function is called from the RFCOMM layer when data
    757  *                  buffer is received from the peer.
    758  *
    759  ******************************************************************************/
    760 void PORT_DataInd(tRFC_MCB* p_mcb, uint8_t dlci, BT_HDR* p_buf) {
    761   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    762   uint8_t rx_char1;
    763   uint32_t events = 0;
    764   uint8_t* p;
    765   int i;
    766 
    767   RFCOMM_TRACE_EVENT(
    768       "PORT_DataInd with data length %d, p_mcb:%p,p_port:%p,dlci:%d",
    769       p_buf->len, p_mcb, p_port, dlci);
    770   if (!p_port) {
    771     osi_free(p_buf);
    772     return;
    773   }
    774   /* If client registered callout callback with flow control we can just deliver
    775    * receive data */
    776   if (p_port->p_data_co_callback) {
    777     /* Another packet is delivered to user.  Send credits to peer if required */
    778     if (p_port->p_data_co_callback(p_port->inx, (uint8_t*)p_buf, -1,
    779                                    DATA_CO_CALLBACK_TYPE_INCOMING)) {
    780       port_flow_control_peer(p_port, true, 1);
    781     } else {
    782       port_flow_control_peer(p_port, false, 0);
    783     }
    784     // osi_free(p_buf);
    785     return;
    786   }
    787   /* If client registered callback we can just deliver receive data */
    788   if (p_port->p_data_callback) {
    789     /* Another packet is delivered to user.  Send credits to peer if required */
    790     port_flow_control_peer(p_port, true, 1);
    791     p_port->p_data_callback(p_port->inx, (uint8_t*)(p_buf + 1) + p_buf->offset,
    792                             p_buf->len);
    793     osi_free(p_buf);
    794     return;
    795   }
    796   /* Check if rx queue exceeds the limit */
    797   if ((p_port->rx.queue_size + p_buf->len > PORT_RX_CRITICAL_WM) ||
    798       (fixed_queue_length(p_port->rx.queue) + 1 > p_port->rx_buf_critical)) {
    799     RFCOMM_TRACE_EVENT("PORT_DataInd. Buffer over run. Dropping the buffer");
    800     osi_free(p_buf);
    801     RFCOMM_LineStatusReq(p_mcb, dlci, LINE_STATUS_OVERRUN);
    802     return;
    803   }
    804   /* If user registered to receive notification when a particular byte is */
    805   /* received we mast check all received bytes */
    806   if (((rx_char1 = p_port->user_port_pars.rx_char1) != 0) &&
    807       (p_port->ev_mask & PORT_EV_RXFLAG)) {
    808     for (i = 0, p = (uint8_t*)(p_buf + 1) + p_buf->offset; i < p_buf->len;
    809          i++) {
    810       if (*p++ == rx_char1) {
    811         events |= PORT_EV_RXFLAG;
    812         break;
    813       }
    814     }
    815   }
    816 
    817   mutex_global_lock();
    818 
    819   fixed_queue_enqueue(p_port->rx.queue, p_buf);
    820   p_port->rx.queue_size += p_buf->len;
    821 
    822   mutex_global_unlock();
    823 
    824   /* perform flow control procedures if necessary */
    825   port_flow_control_peer(p_port, false, 0);
    826 
    827   /* If user indicated flow control can not deliver any notifications to him */
    828   if (p_port->rx.user_fc) {
    829     if (events & PORT_EV_RXFLAG) {
    830       p_port->rx_flag_ev_pending = true;
    831     }
    832     return;
    833   }
    834 
    835   events |= PORT_EV_RXCHAR;
    836 
    837   /* Mask out all events that are not of interest to user */
    838   events &= p_port->ev_mask;
    839 
    840   if (p_port->p_callback && events) p_port->p_callback(events, p_port->inx);
    841 }
    842 
    843 /*******************************************************************************
    844  *
    845  * Function         PORT_FlowInd
    846  *
    847  * Description      This function is called from the RFCOMM layer on the flow
    848  *                  control signal change.  Propagate change to the user.
    849  *
    850  ******************************************************************************/
    851 void PORT_FlowInd(tRFC_MCB* p_mcb, uint8_t dlci, bool enable_data) {
    852   tPORT* p_port = (tPORT*)NULL;
    853   uint32_t events = 0;
    854   int i;
    855 
    856   RFCOMM_TRACE_EVENT("PORT_FlowInd fc:%d", enable_data);
    857 
    858   if (dlci == 0) {
    859     p_mcb->peer_ready = enable_data;
    860   } else {
    861     p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    862     if (p_port == NULL) return;
    863 
    864     p_port->tx.peer_fc = !enable_data;
    865   }
    866 
    867   for (i = 0; i < MAX_RFC_PORTS; i++) {
    868     /* If DLCI is 0 event applies to all ports */
    869     if (dlci == 0) {
    870       p_port = &rfc_cb.port.port[i];
    871       if (!p_port->in_use || (p_port->rfc.p_mcb != p_mcb) ||
    872           (p_port->rfc.state != RFC_STATE_OPENED))
    873         continue;
    874     }
    875     events = 0;
    876 
    877     /* Check if flow of data is still enabled */
    878     events |= port_flow_control_user(p_port);
    879 
    880     /* Check if data can be sent and send it */
    881     events |= port_rfc_send_tx_data(p_port);
    882 
    883     /* Mask out all events that are not of interest to user */
    884     events &= p_port->ev_mask;
    885 
    886     /* Send event to the application */
    887     if (p_port->p_callback && events) (p_port->p_callback)(events, p_port->inx);
    888 
    889     /* If DLCI is not 0 event applies to one port only */
    890     if (dlci != 0) break;
    891   }
    892 }
    893 
    894 /*******************************************************************************
    895  *
    896  * Function         port_rfc_send_tx_data
    897  *
    898  * Description      This function is when forward data can be sent to the peer
    899  *
    900  ******************************************************************************/
    901 uint32_t port_rfc_send_tx_data(tPORT* p_port) {
    902   uint32_t events = 0;
    903   BT_HDR* p_buf;
    904 
    905   /* if there is data to be sent */
    906   if (p_port->tx.queue_size > 0) {
    907     /* while the rfcomm peer is not flow controlling us, and peer is ready */
    908     while (!p_port->tx.peer_fc && p_port->rfc.p_mcb &&
    909            p_port->rfc.p_mcb->peer_ready) {
    910       /* get data from tx queue and send it */
    911       mutex_global_lock();
    912 
    913       p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_port->tx.queue);
    914       if (p_buf != NULL) {
    915         p_port->tx.queue_size -= p_buf->len;
    916 
    917         mutex_global_unlock();
    918 
    919         RFCOMM_TRACE_DEBUG("Sending RFCOMM_DataReq tx.queue_size=%d",
    920                            p_port->tx.queue_size);
    921 
    922         RFCOMM_DataReq(p_port->rfc.p_mcb, p_port->dlci, p_buf);
    923 
    924         events |= PORT_EV_TXCHAR;
    925 
    926         if (p_port->tx.queue_size == 0) {
    927           events |= PORT_EV_TXEMPTY;
    928           break;
    929         }
    930       }
    931       /* queue is empty-- all data sent */
    932       else {
    933         mutex_global_unlock();
    934 
    935         events |= PORT_EV_TXEMPTY;
    936         break;
    937       }
    938     }
    939     /* If we flow controlled user based on the queue size enable data again */
    940     events |= port_flow_control_user(p_port);
    941   }
    942   return (events & p_port->ev_mask);
    943 }
    944 
    945 /*******************************************************************************
    946  *
    947  * Function         port_rfc_closed
    948  *
    949  * Description      Called when RFCOMM port is closed
    950  *
    951  ******************************************************************************/
    952 void port_rfc_closed(tPORT* p_port, uint8_t res) {
    953   uint8_t old_signals;
    954   uint32_t events = 0;
    955   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    956 
    957   if ((p_port->state == PORT_STATE_OPENING) && (p_port->is_server)) {
    958     /* The server side was not informed that connection is up, ignore */
    959     RFCOMM_TRACE_WARNING("port_rfc_closed in OPENING state ignored");
    960 
    961     rfc_port_timer_stop(p_port);
    962     p_port->rfc.state = RFC_STATE_CLOSED;
    963 
    964     if (p_mcb) {
    965       p_mcb->port_inx[p_port->dlci] = 0;
    966 
    967       /* If there are no more ports opened on this MCB release it */
    968       rfc_check_mcb_active(p_mcb);
    969       p_port->rfc.p_mcb = NULL;
    970     }
    971 
    972     /* Need to restore DLCI to listening state
    973      * if the server was on the initiating RFC
    974      */
    975     p_port->dlci &= 0xfe;
    976 
    977     return;
    978   }
    979 
    980   if ((p_port->state != PORT_STATE_CLOSING) &&
    981       (p_port->state != PORT_STATE_CLOSED)) {
    982     p_port->line_status |= LINE_STATUS_FAILED;
    983 
    984     old_signals = p_port->peer_ctrl.modem_signal;
    985 
    986     p_port->peer_ctrl.modem_signal &=
    987         ~(PORT_DTRDSR_ON | PORT_CTSRTS_ON | PORT_DCD_ON);
    988 
    989     events |= port_get_signal_changes(p_port, old_signals,
    990                                       p_port->peer_ctrl.modem_signal);
    991 
    992     if (p_port->ev_mask & PORT_EV_CONNECT_ERR) events |= PORT_EV_CONNECT_ERR;
    993   }
    994 
    995   if ((p_port->p_callback != NULL) && events)
    996     p_port->p_callback(events, p_port->inx);
    997 
    998   if (p_port->p_mgmt_callback) p_port->p_mgmt_callback(res, p_port->inx);
    999 
   1000   p_port->rfc.state = RFC_STATE_CLOSED;
   1001 
   1002   RFCOMM_TRACE_WARNING(
   1003       "%s: RFCOMM connection closed, index=%d, state=%d reason=%s[%d], "
   1004       "UUID=%04X, bd_addr=%s, is_server=%d",
   1005       __func__, p_port->inx, p_port->state, PORT_GetResultString(res), res,
   1006       p_port->uuid, p_port->bd_addr.ToString().c_str(), p_port->is_server);
   1007 
   1008   port_release_port(p_port);
   1009 }
   1010 
   1011 /*******************************************************************************
   1012  *
   1013  * Function         port_get_credits
   1014  *
   1015  * Description      Set initial values for credits.
   1016  *                  Adjust max number of rx credits based on negotiated MTU.
   1017  *                  Check max allowed num of bytes, max allowed num buffers,
   1018  *                  should be less then 255
   1019  *
   1020  ******************************************************************************/
   1021 void port_get_credits(tPORT* p_port, uint8_t k) {
   1022   p_port->credit_tx = k;
   1023   if (p_port->credit_tx == 0) p_port->tx.peer_fc = true;
   1024 }
   1025