xref: /external/bluetooth/bluedroid/stack/gatt/gatt_sr.c

/******************************************************************************
 *
 *  Copyright (C) 2008-2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  this file contains the GATT server functions
 *
 ******************************************************************************/

#include "bt_target.h"

#if BLE_INCLUDED == TRUE
#include <string.h>
#include "gatt_int.h"
#include "l2c_api.h"

#define GATT_MTU_REQ_MIN_LEN        2


/*******************************************************************************
**
** Function         gatt_sr_enqueue_cmd
**
** Description      This function enqueue the request from client which needs a
**                  application response, and update the transaction ID.
**
** Returns          void
**
*******************************************************************************/
UINT32 gatt_sr_enqueue_cmd (tGATT_TCB *p_tcb, UINT8 op_code, UINT16 handle)
{
    tGATT_SR_CMD   *p_cmd = &p_tcb->sr_cmd;
    UINT32          trans_id = 0;

    if ( (p_cmd->op_code == 0) ||
         (op_code == GATT_HANDLE_VALUE_CONF)) /* no pending request */
    {
        if (op_code == GATT_CMD_WRITE ||
            op_code == GATT_SIGN_CMD_WRITE  ||
            op_code == GATT_REQ_MTU ||
            op_code == GATT_HANDLE_VALUE_CONF)
        {
            trans_id = ++p_tcb->trans_id;
        }
        else
        {
            p_cmd->trans_id   = ++p_tcb->trans_id;
            p_cmd->op_code    = op_code;
            p_cmd->handle     = handle;
            p_cmd->status     = GATT_NOT_FOUND;
            p_tcb->trans_id %= GATT_TRANS_ID_MAX;
            trans_id = p_cmd->trans_id;
        }
    }

    return trans_id;
}

/*******************************************************************************
**
** Function         gatt_sr_cmd_empty
**
** Description      This function check the server command queue is empty or not.
**
** Returns          TRUE if empty, FALSE if there is pending command.
**
*******************************************************************************/
BOOLEAN gatt_sr_cmd_empty (tGATT_TCB *p_tcb)
{
    return(p_tcb->sr_cmd.op_code == 0);
}

/*******************************************************************************
**
** Function         gatt_dequeue_sr_cmd
**
** Description      This function dequeue the request from command queue.
**
** Returns          void
**
*******************************************************************************/
void gatt_dequeue_sr_cmd (tGATT_TCB *p_tcb)
{
    /* Double check in case any buffers are queued */
    GATT_TRACE_DEBUG0("gatt_dequeue_sr_cmd" );
    if (p_tcb->sr_cmd.p_rsp_msg)
    {
        GATT_TRACE_ERROR1("free p_tcb->sr_cmd.p_rsp_msg = %d", p_tcb->sr_cmd.p_rsp_msg);

        GKI_freebuf (p_tcb->sr_cmd.p_rsp_msg);
    }

    while (p_tcb->sr_cmd.multi_rsp_q.p_first)
        GKI_freebuf (GKI_dequeue (&p_tcb->sr_cmd.multi_rsp_q));
    memset( &p_tcb->sr_cmd, 0, sizeof(tGATT_SR_CMD));
}

/*******************************************************************************
**
** Function         process_read_multi_rsp
**
** Description      This function check the read multiple response.
**
** Returns          BOOLEAN if all replies have been received
**
*******************************************************************************/
static BOOLEAN process_read_multi_rsp (tGATT_SR_CMD *p_cmd, tGATT_STATUS status,
                                       tGATTS_RSP *p_msg, UINT16 mtu)
{
    tGATTS_RSP       *p_rsp;
    UINT16          ii, total_len, len;
    BT_HDR          *p_buf = (BT_HDR *)GKI_getbuf((UINT16)sizeof(tGATTS_RSP));
    UINT8           *p;
    BOOLEAN         is_overflow = FALSE;

    GATT_TRACE_DEBUG2 ("process_read_multi_rsp status=%d mtu=%d", status, mtu);

    if (p_buf == NULL)
    {
        p_cmd->status = GATT_INSUF_RESOURCE;
        return FALSE;
    }

    /* Enqueue the response */
    memcpy((void *)p_buf, (const void *)p_msg, sizeof(tGATTS_RSP));
    GKI_enqueue (&p_cmd->multi_rsp_q, p_buf);

    p_cmd->status = status;
    if (status == GATT_SUCCESS)
    {
        GATT_TRACE_DEBUG2 ("Multi read count=%d num_hdls=%d",
                           p_cmd->multi_rsp_q.count, p_cmd->multi_req.num_handles);
        /* Wait till we get all the responses */
        if (p_cmd->multi_rsp_q.count == p_cmd->multi_req.num_handles)
        {
            len = sizeof(BT_HDR) + L2CAP_MIN_OFFSET + mtu;
            if ((p_buf = (BT_HDR *)GKI_getbuf(len)) == NULL)
            {
                p_cmd->status = GATT_INSUF_RESOURCE;
                return(TRUE);
            }

            memset(p_buf, 0, len);
            p_buf->offset = L2CAP_MIN_OFFSET;
            p = (UINT8 *)(p_buf + 1) + p_buf->offset;

            /* First byte in the response is the opcode */
            *p++ = GATT_RSP_READ_MULTI;
            p_buf->len = 1;

            /* Now walk through the buffers puting the data into the response in order */
            for (ii = 0; ii < p_cmd->multi_req.num_handles; ii++)
            {
                if (ii==0)
                {
                    p_rsp = (tGATTS_RSP *)GKI_getfirst (&p_cmd->multi_rsp_q);
                }
                else
                {
                    p_rsp = (tGATTS_RSP *)GKI_getnext (p_rsp);
                }

                if (p_rsp != NULL)
                {

                    total_len = (p_buf->len + p_rsp->attr_value.len);

                    if (total_len >  mtu)
                    {
                        /* just send the partial response for the overflow case */
                        len = p_rsp->attr_value.len - (total_len - mtu);
                        is_overflow = TRUE;
                        GATT_TRACE_DEBUG2 ("multi read overflow available len=%d val_len=%d", len, p_rsp->attr_value.len );
                    }
                    else
                    {
                        len = p_rsp->attr_value.len;
                    }

                    if (p_rsp->attr_value.handle == p_cmd->multi_req.handles[ii])
                    {
                        memcpy (p, p_rsp->attr_value.value, len);
                        if (!is_overflow)
                            p += len;
                        p_buf->len += len;
                    }
                    else
                    {
                        p_cmd->status        = GATT_NOT_FOUND;
                        break;
                    }

                    if (is_overflow)
                        break;

                }
                else
                {
                    p_cmd->status        = GATT_NOT_FOUND;
                    break;
                }

            } /* loop through all handles*/


            /* Sanity check on the buffer length */
            if (p_buf->len == 0)
            {
                GATT_TRACE_ERROR0("process_read_multi_rsp - nothing found!!");
                p_cmd->status = GATT_NOT_FOUND;
                GKI_freebuf (p_buf);
                GATT_TRACE_DEBUG0(" GKI_freebuf (p_buf)");
            }
            else if (p_cmd->p_rsp_msg != NULL)
            {
                GKI_freebuf (p_buf);
            }
            else
            {
                p_cmd->p_rsp_msg = p_buf;
            }

            return(TRUE);
        }
    }
    else    /* any handle read exception occurs, return error */
    {
        return(TRUE);
    }

    /* If here, still waiting */
    return(FALSE);
}

/*******************************************************************************
**
** Function         gatt_sr_process_app_rsp
**
** Description      This function checks whether the response message from application
**                  match any pending request or not.
**
** Returns          void
**
*******************************************************************************/
tGATT_STATUS gatt_sr_process_app_rsp (tGATT_TCB *p_tcb, tGATT_IF gatt_if,
                                      UINT32 trans_id, UINT8 op_code,
                                      tGATT_STATUS status, tGATTS_RSP *p_msg)
{
    tGATT_STATUS    ret_code = GATT_SUCCESS;

    GATT_TRACE_DEBUG1("gatt_sr_process_app_rsp gatt_if=%d", gatt_if);

    gatt_sr_update_cback_cnt(p_tcb, gatt_if, FALSE, FALSE);

    if (op_code == GATT_REQ_READ_MULTI)
    {
        /* If no error and still waiting, just return */
        if (!process_read_multi_rsp (&p_tcb->sr_cmd, status, p_msg, p_tcb->payload_size))
            return(GATT_SUCCESS);
    }
    else
    {
        if (op_code == GATT_REQ_PREPARE_WRITE && status == GATT_SUCCESS)
            gatt_sr_update_prep_cnt(p_tcb, gatt_if, TRUE, FALSE);

        if (op_code == GATT_REQ_EXEC_WRITE && status != GATT_SUCCESS)
            gatt_sr_reset_cback_cnt(p_tcb);

        p_tcb->sr_cmd.status = status;

        if (gatt_sr_is_cback_cnt_zero(p_tcb)
            && status == GATT_SUCCESS)
        {
            if (p_tcb->sr_cmd.p_rsp_msg == NULL)
            {
                p_tcb->sr_cmd.p_rsp_msg = attp_build_sr_msg (p_tcb, (UINT8)(op_code + 1), (tGATT_SR_MSG *)p_msg);
            }
            else
            {
                GATT_TRACE_ERROR0("Exception!!! already has respond message");
            }
        }
    }
    if (gatt_sr_is_cback_cnt_zero(p_tcb))
    {
        if ( (p_tcb->sr_cmd.status == GATT_SUCCESS) && (p_tcb->sr_cmd.p_rsp_msg) )
        {
            ret_code = attp_send_sr_msg (p_tcb, p_tcb->sr_cmd.p_rsp_msg);
            p_tcb->sr_cmd.p_rsp_msg = NULL;
        }
        else
        {
            ret_code = gatt_send_error_rsp (p_tcb, status, op_code, p_tcb->sr_cmd.handle, FALSE);
        }

        gatt_dequeue_sr_cmd(p_tcb);
    }

    GATT_TRACE_DEBUG1("gatt_sr_process_app_rsp ret_code=%d", ret_code);

    return ret_code;
}

/*******************************************************************************
**
** Function         gatt_process_exec_write_req
**
** Description      This function is called to process the execute write request
**                  from client.
**
** Returns          void
**
*******************************************************************************/
void gatt_process_exec_write_req (tGATT_TCB *p_tcb, UINT8 op_code, UINT16 len, UINT8 *p_data)
{
    UINT8   *p = p_data, flag, i = 0;
    UINT32  trans_id = 0;
    BT_HDR  *p_buf;
    tGATT_IF gatt_if;
    UINT16  conn_id;

#if GATT_CONFORMANCE_TESTING == TRUE
    if (gatt_cb.enable_err_rsp && gatt_cb.req_op_code == op_code)
    {
        GATT_TRACE_DEBUG2("conf test forced err rsp for %s error status=%d",
                           __FUNCTION__,gatt_cb.err_status);

        gatt_send_error_rsp (p_tcb, gatt_cb.err_status, gatt_cb.req_op_code, gatt_cb.handle, FALSE);

        return;
    }
#endif

    STREAM_TO_UINT8(flag, p);

    /* mask the flag */
    flag &= GATT_PREP_WRITE_EXEC;


    /* no prep write is queued */
    if (!gatt_sr_is_prep_cnt_zero(p_tcb))
    {
        trans_id = gatt_sr_enqueue_cmd(p_tcb, op_code, 0);
        gatt_sr_copy_prep_cnt_to_cback_cnt(p_tcb);

        for (i=0; i<GATT_MAX_APPS; i++)
        {
            if (p_tcb->prep_cnt[i])
            {
                gatt_if = (tGATT_IF) (i+1);
                conn_id = GATT_CREATE_CONN_ID(p_tcb->tcb_idx, gatt_if);
                gatt_sr_send_req_callback(conn_id,
                                          trans_id,
                                          GATTS_REQ_TYPE_WRITE_EXEC,
                                          (tGATTS_DATA *)&flag);
                p_tcb->prep_cnt[i]= 0;
            }
        }
    }
    else /* nothing needs to be executed , send response now */
    {
        GATT_TRACE_ERROR0("gatt_process_exec_write_req: no prepare write pending");

        if ((p_buf = attp_build_sr_msg(p_tcb, GATT_RSP_EXEC_WRITE, NULL)) != NULL)
        {
            attp_send_sr_msg (p_tcb, p_buf);
        }

    }
}

/*******************************************************************************
**
** Function         gatt_process_read_multi_req
**
** Description      This function is called to process the read multiple request
**                  from client.
**
** Returns          void
**
*******************************************************************************/
void gatt_process_read_multi_req (tGATT_TCB *p_tcb, UINT8 op_code, UINT16 len, UINT8 *p_data)
{
    UINT32          trans_id;
    UINT16          handle = 0, ll = len;
    UINT8           *p = p_data, i_rcb;
    tGATT_STATUS    err = GATT_SUCCESS;
    UINT8           sec_flag, key_size;
    tGATTS_RSP       *p_msg;

    GATT_TRACE_DEBUG0("gatt_process_read_multi_req" );
    p_tcb->sr_cmd.multi_req.num_handles = 0;

    gatt_sr_get_sec_info(p_tcb->peer_bda,
                         (BOOLEAN)(p_tcb->att_lcid == L2CAP_ATT_CID),
                         &sec_flag,
                         &key_size);

#if GATT_CONFORMANCE_TESTING == TRUE
    if (gatt_cb.enable_err_rsp && gatt_cb.req_op_code == op_code)
    {
        GATT_TRACE_DEBUG1("Conformance tst: forced err rspvofr ReadMultiple: error status=%d", gatt_cb.err_status);

        STREAM_TO_UINT16(handle, p);

        gatt_send_error_rsp (p_tcb, gatt_cb.err_status, gatt_cb.req_op_code, handle, FALSE);

        return;
    }
#endif

    while (ll >= 2 && p_tcb->sr_cmd.multi_req.num_handles < GATT_MAX_READ_MULTI_HANDLES)
    {
        STREAM_TO_UINT16(handle, p);

        if ((i_rcb = gatt_sr_find_i_rcb_by_handle(handle)) < GATT_MAX_SR_PROFILES)
        {
            p_tcb->sr_cmd.multi_req.handles[p_tcb->sr_cmd.multi_req.num_handles++] = handle;

            /* check read permission */
            if ((err = gatts_read_attr_perm_check(   gatt_cb.sr_reg[i_rcb].p_db,
                                                     FALSE,
                                                     handle,
                                                     sec_flag,
                                                     key_size))
                != GATT_SUCCESS)
            {
                GATT_TRACE_DEBUG1("read permission denied : 0x%02x", err);
                break;
            }
        }
        else
        {
            /* invalid handle */
            err = GATT_INVALID_HANDLE;
            break;
        }
        ll -= 2;
    }

    if (ll != 0)
    {
        GATT_TRACE_ERROR0("max attribute handle reached in ReadMultiple Request.");
    }

    if (p_tcb->sr_cmd.multi_req.num_handles == 0)
        err = GATT_INVALID_HANDLE;

    if (err == GATT_SUCCESS)
    {
        if ((trans_id = gatt_sr_enqueue_cmd (p_tcb, op_code, p_tcb->sr_cmd.multi_req.handles[0])) != 0)
        {
            gatt_sr_reset_cback_cnt(p_tcb); /* read multiple use multi_rsp_q's count*/

            for (ll = 0; ll < p_tcb->sr_cmd.multi_req.num_handles; ll ++)
            {
                if ((p_msg = (tGATTS_RSP *)GKI_getbuf(sizeof(tGATTS_RSP))) != NULL)
                {
                    memset(p_msg, 0, sizeof(tGATTS_RSP))
                    ;
                    handle = p_tcb->sr_cmd.multi_req.handles[ll];
                    i_rcb = gatt_sr_find_i_rcb_by_handle(handle);

                    p_msg->attr_value.handle = handle;
                    err = gatts_read_attr_value_by_handle(p_tcb,
                                                          gatt_cb.sr_reg[i_rcb].p_db,
                                                          op_code,
                                                          handle,
                                                          0,
                                                          p_msg->attr_value.value,
                                                          &p_msg->attr_value.len,
                                                          GATT_MAX_ATTR_LEN,
                                                          sec_flag,
                                                          key_size,
                                                          trans_id);

                    if (err == GATT_SUCCESS)
                    {
                        gatt_sr_process_app_rsp(p_tcb, gatt_cb.sr_reg[i_rcb].gatt_if ,trans_id, op_code, GATT_SUCCESS, p_msg);
                    }
                    /* either not using or done using the buffer, release it now */
                    GKI_freebuf(p_msg);
                }
                else
                {
                    err = GATT_NO_RESOURCES;
                    gatt_dequeue_sr_cmd(p_tcb);
                    break;
                }
            }
        }
        else
            err = GATT_NO_RESOURCES;
    }

    /* in theroy BUSY is not possible(should already been checked), protected check */
    if (err != GATT_SUCCESS && err != GATT_PENDING && err != GATT_BUSY)
        gatt_send_error_rsp(p_tcb, err, op_code, handle, FALSE);
}

/*******************************************************************************
**
** Function         gatt_build_primary_service_rsp
**
** Description      Primamry service request processed internally. Theretically
**                  only deal with ReadByTypeVAlue and ReadByGroupType.
**
** Returns          void
**
*******************************************************************************/
static tGATT_STATUS gatt_build_primary_service_rsp (BT_HDR *p_msg, tGATT_TCB *p_tcb,
                                                    UINT8 op_code, UINT16 s_hdl,
                                                    UINT16 e_hdl, UINT8 *p_data, tBT_UUID value)
{
    tGATT_STATUS    status = GATT_NOT_FOUND;
    UINT8           handle_len =4, *p ;
    tGATT_SR_REG    *p_rcb;
    tGATT_SRV_LIST_INFO *p_list= &gatt_cb.srv_list_info;
    tGATT_SRV_LIST_ELEM  *p_srv=NULL;
    tBT_UUID       *p_uuid;

    p = (UINT8 *)(p_msg + 1) + L2CAP_MIN_OFFSET;

    p_srv = p_list->p_first;

    while (p_srv)
    {
        p_rcb = GATT_GET_SR_REG_PTR(p_srv->i_sreg);

        if (p_rcb->in_use &&
            p_rcb->s_hdl >= s_hdl &&
            p_rcb->s_hdl <= e_hdl &&
            p_rcb->type == GATT_UUID_PRI_SERVICE)
        {
            if ((p_uuid = gatts_get_service_uuid (p_rcb->p_db)) != NULL)
            {
                if (op_code == GATT_REQ_READ_BY_GRP_TYPE)
                    handle_len = 4 + p_uuid->len;

                /* get the length byte in the repsonse */
                if (p_msg->offset ==0)
                {
                    *p ++ = op_code + 1;
                    p_msg->len ++;
                    p_msg->offset = handle_len;

                    if (op_code == GATT_REQ_READ_BY_GRP_TYPE)
                    {
                        *p ++ =  (UINT8)p_msg->offset; /* length byte */
                        p_msg->len ++;
                    }
                }

                if (p_msg->len + p_msg->offset <= p_tcb->payload_size &&
                    handle_len == p_msg->offset)
                {
                    if (op_code != GATT_REQ_FIND_TYPE_VALUE ||
                        gatt_uuid_compare(value, *p_uuid))
                    {
                        UINT16_TO_STREAM(p, p_rcb->s_hdl);

                        if (p_list->p_last_primary == p_srv &&
                            p_list->p_last_primary == p_list->p_last)
                        {
                            GATT_TRACE_DEBUG0("Use 0xFFFF for the last primary attribute");
                            UINT16_TO_STREAM(p, 0xFFFF); /* see GATT ERRATA 4065, 4063, ATT ERRATA 4062 */
                        }
                        else
                        {
                            UINT16_TO_STREAM(p, p_rcb->e_hdl);
                        }

                        if (op_code == GATT_REQ_READ_BY_GRP_TYPE)
                            gatt_build_uuid_to_stream(&p, *p_uuid);

                        status = GATT_SUCCESS;
                        p_msg->len += p_msg->offset;
                    }
                }
                else
                    break;
            }
        }
        p_srv = p_srv->p_next;
    }
    p_msg->offset = L2CAP_MIN_OFFSET;

    return status;
}

/*******************************************************************************
**
** Function         gatt_build_find_info_rsp
**
** Description      fill the find information response information in the given
**                  buffer.
**
** Returns          TRUE: if data filled sucessfully.
**                  FALSE: packet full, or format mismatch.
**
*******************************************************************************/
static tGATT_STATUS gatt_build_find_info_rsp(tGATT_SR_REG *p_rcb, BT_HDR *p_msg, UINT16 *p_len,
                                             UINT16 s_hdl, UINT16 e_hdl)
{
    tGATT_STATUS        status = GATT_NOT_FOUND;
    UINT8               *p;
    UINT16              len = *p_len;
    tGATT_ATTR16        *p_attr = NULL;
    UINT8               info_pair_len[2] = {4, 18};

    if (!p_rcb->p_db || !p_rcb->p_db->p_attr_list)
        return status;

    /* check the attribute database */
    p_attr = (tGATT_ATTR16 *) p_rcb->p_db->p_attr_list;

    p = (UINT8 *)(p_msg + 1) + L2CAP_MIN_OFFSET + p_msg->len;

    while (p_attr)
    {
        if (p_attr->handle > e_hdl)
        {
            break;
        }

        if (p_attr->handle >= s_hdl)
        {
            if (p_msg->offset == 0)
                p_msg->offset = (p_attr->uuid_type == GATT_ATTR_UUID_TYPE_128) ? GATT_INFO_TYPE_PAIR_128 : GATT_INFO_TYPE_PAIR_16;

            if (len >= info_pair_len[p_msg->offset - 1])
            {
                if (p_msg->offset == GATT_INFO_TYPE_PAIR_16 && p_attr->uuid_type == GATT_ATTR_UUID_TYPE_16)
                {
                    UINT16_TO_STREAM(p, p_attr->handle);
                    UINT16_TO_STREAM(p, p_attr->uuid);
                }
                else if (p_msg->offset == GATT_INFO_TYPE_PAIR_128 &&
                         p_attr->uuid_type == GATT_ATTR_UUID_TYPE_128  )
                {
                    UINT16_TO_STREAM(p, p_attr->handle);
                    ARRAY_TO_STREAM (p, ((tGATT_ATTR128 *) p_attr)->uuid, LEN_UUID_128);
                }
                else
                {
                    GATT_TRACE_ERROR0("format mismatch");
                    status = GATT_NO_RESOURCES;
                    break;
                    /* format mismatch */
                }
                p_msg->len += info_pair_len[p_msg->offset - 1];
                len -= info_pair_len[p_msg->offset - 1];
                status = GATT_SUCCESS;

            }
            else
            {
                status = GATT_NO_RESOURCES;
                break;
            }
        }
        p_attr = (tGATT_ATTR16 *)p_attr->p_next;
    }

    *p_len = len;
    return status;
}

/*******************************************************************************
**
** Function         gatts_internal_read_by_type_req
**
** Description      check to see if the ReadByType request can be handled internally.
**
** Returns          void
**
*******************************************************************************/
static tGATT_STATUS gatts_validate_packet_format(UINT8 op_code, UINT16 *p_len,
                                                 UINT8 **p_data, tBT_UUID *p_uuid_filter,
                                                 UINT16 *p_s_hdl, UINT16 *p_e_hdl)
{
    tGATT_STATUS    reason = GATT_SUCCESS;
    UINT16          uuid_len, s_hdl = 0, e_hdl = 0;
    UINT16          len = *p_len;
    UINT8           *p = *p_data;

    if (len >= 4)
    {
        /* obtain starting handle, and ending handle */
        STREAM_TO_UINT16(s_hdl, p);
        STREAM_TO_UINT16(e_hdl, p);
        len -= 4;

        if (s_hdl > e_hdl || !GATT_HANDLE_IS_VALID(s_hdl) || !GATT_HANDLE_IS_VALID(e_hdl))
        {
            reason = GATT_INVALID_HANDLE;
        }
        /* for these PDUs, uuid filter must present */
        else if (op_code == GATT_REQ_READ_BY_GRP_TYPE ||
                 op_code == GATT_REQ_FIND_TYPE_VALUE ||
                 op_code == GATT_REQ_READ_BY_TYPE)
        {
            if (len >= 2 && p_uuid_filter != NULL)
            {
                uuid_len = (op_code == GATT_REQ_FIND_TYPE_VALUE) ? 2 : len;

                /* parse uuid now */
                if (gatt_parse_uuid_from_cmd (p_uuid_filter, uuid_len, &p) == FALSE ||
                    p_uuid_filter->len == 0)
                {
                    GATT_TRACE_DEBUG0("UUID filter does not exsit");
                    reason = GATT_INVALID_PDU;
                }
                else
                    len -= p_uuid_filter->len;
            }
            else
                reason = GATT_INVALID_PDU;
        }
    }
    else
        reason = GATT_INVALID_PDU;

    *p_data     = p;
    *p_len      = len;
    *p_s_hdl    = s_hdl;
    *p_e_hdl    = e_hdl;

    return reason;
}

/*******************************************************************************
**
** Function         gatts_process_primary_service_req
**
** Description      process ReadByGroupType/ReadByTypeValue request, for discover
**                  all primary services or discover primary service by UUID request.
**
** Returns          void
**
*******************************************************************************/
void gatts_process_primary_service_req(tGATT_TCB *p_tcb, UINT8 op_code, UINT16 len, UINT8 *p_data)
{
    UINT8           reason = GATT_INVALID_PDU;
    UINT16          s_hdl = 0, e_hdl = 0;
    tBT_UUID        uuid, value, primary_service = {LEN_UUID_16, {GATT_UUID_PRI_SERVICE}};
    BT_HDR          *p_msg = NULL;
    UINT16          msg_len = (UINT16)(sizeof(BT_HDR) + p_tcb->payload_size + L2CAP_MIN_OFFSET);

    reason = gatts_validate_packet_format(op_code, &len, &p_data, &uuid, &s_hdl, &e_hdl);

    if (reason == GATT_SUCCESS)
    {
        if (gatt_uuid_compare(uuid, primary_service))
        {
            if (op_code == GATT_REQ_FIND_TYPE_VALUE)
            {
                if (gatt_parse_uuid_from_cmd(&value, len, &p_data) == FALSE)
                    reason = GATT_INVALID_PDU;
            }

            if (reason == GATT_SUCCESS)
            {
                if ((p_msg =  (BT_HDR *)GKI_getbuf(msg_len)) == NULL)
                {
                    GATT_TRACE_ERROR0("gatts_process_primary_service_req failed. no resources.");
                    reason = GATT_NO_RESOURCES;
                }
                else
                {
                    memset(p_msg, 0, msg_len);
                    reason = gatt_build_primary_service_rsp (p_msg, p_tcb, op_code, s_hdl, e_hdl, p_data, value);
                }
            }
        }
        else
        {
            if (op_code == GATT_REQ_READ_BY_GRP_TYPE)
            {
                reason = GATT_UNSUPPORT_GRP_TYPE;
                GATT_TRACE_DEBUG1("unexpected ReadByGrpType Group: 0x%04x", uuid.uu.uuid16);
            }
            else
            {
                /* we do not support ReadByTypeValue with any non-primamry_service type */
                reason = GATT_NOT_FOUND;
                GATT_TRACE_DEBUG1("unexpected ReadByTypeValue type: 0x%04x", uuid.uu.uuid16);
            }
        }
    }

    if (reason != GATT_SUCCESS)
    {
        if (p_msg) GKI_freebuf(p_msg);
        gatt_send_error_rsp (p_tcb, reason, op_code, s_hdl, FALSE);
    }
    else
        attp_send_sr_msg(p_tcb, p_msg);

}

/*******************************************************************************
**
** Function         gatts_process_find_info
**
** Description      process find information request, for discover character
**                  descriptors.
**
** Returns          void
**
*******************************************************************************/
static void gatts_process_find_info(tGATT_TCB *p_tcb, UINT8 op_code, UINT16 len, UINT8 *p_data)
{
    UINT8           reason = GATT_INVALID_PDU, *p;
    UINT16          s_hdl = 0, e_hdl = 0, buf_len;
    BT_HDR          *p_msg = NULL;
    tGATT_SR_REG    *p_rcb;
    tGATT_SRV_LIST_INFO *p_list= &gatt_cb.srv_list_info;
    tGATT_SRV_LIST_ELEM  *p_srv=NULL;

    reason = gatts_validate_packet_format(op_code, &len, &p_data, NULL, &s_hdl, &e_hdl);

    if (reason == GATT_SUCCESS)
    {
        buf_len = (UINT16)(sizeof(BT_HDR) + p_tcb->payload_size + L2CAP_MIN_OFFSET);

        if ((p_msg =  (BT_HDR *)GKI_getbuf(buf_len)) == NULL)
        {
            reason = GATT_NO_RESOURCES;
        }
        else
        {
            reason = GATT_NOT_FOUND;

            memset(p_msg, 0, buf_len);
            p = (UINT8 *)(p_msg + 1) + L2CAP_MIN_OFFSET;
            *p ++ = op_code + 1;
            p_msg->len = 2;

            buf_len = p_tcb->payload_size - 2;

            p_srv = p_list->p_first;

            while (p_srv)
            {
                p_rcb = GATT_GET_SR_REG_PTR(p_srv->i_sreg);

                if (p_rcb->in_use &&
                    !(p_rcb->s_hdl > e_hdl ||
                      p_rcb->e_hdl < s_hdl))
                {
                    reason = gatt_build_find_info_rsp(p_rcb, p_msg, &buf_len, s_hdl, e_hdl);
                    if (reason == GATT_NO_RESOURCES)
                    {
                        reason = GATT_SUCCESS;
                        break;
                    }
                }
                p_srv = p_srv->p_next;
            }
            *p = (UINT8)p_msg->offset;

            p_msg->offset = L2CAP_MIN_OFFSET;
        }
    }

    if (reason != GATT_SUCCESS)
    {
        if (p_msg)  GKI_freebuf(p_msg);
        gatt_send_error_rsp (p_tcb, reason, op_code, s_hdl, FALSE);
    }
    else
        attp_send_sr_msg(p_tcb, p_msg);

}

/*******************************************************************************
**
** Function         gatts_process_mtu_req
**
** Description      This function is called to process excahnge MTU request.
**                  Only used on LE.
**
** Returns          void
**
*******************************************************************************/
static void gatts_process_mtu_req (tGATT_TCB *p_tcb, UINT16 len, UINT8 *p_data)
{
    UINT16        mtu = 0;
    UINT8         *p = p_data, i;
    BT_HDR        *p_buf;
    UINT16   conn_id;

    /* BR/EDR conenction, send error response */
    if (p_tcb->att_lcid != L2CAP_ATT_CID)
    {
        gatt_send_error_rsp (p_tcb, GATT_REQ_NOT_SUPPORTED, GATT_REQ_MTU, 0, FALSE);
    }
    else if (len < GATT_MTU_REQ_MIN_LEN)
    {
        GATT_TRACE_ERROR0("invalid MTU request PDU received.");
        gatt_send_error_rsp (p_tcb, GATT_INVALID_PDU, GATT_REQ_MTU, 0, FALSE);
    }
    else
    {
        STREAM_TO_UINT16 (mtu, p);
        /* mtu must be greater than default MTU which is 23/48 */
        if (mtu < GATT_DEF_BLE_MTU_SIZE)
            p_tcb->payload_size = GATT_DEF_BLE_MTU_SIZE;
        else if (mtu > GATT_MAX_MTU_SIZE)
            p_tcb->payload_size = GATT_MAX_MTU_SIZE;
        else
            p_tcb->payload_size = mtu;

        if ((p_buf = attp_build_sr_msg(p_tcb, GATT_RSP_MTU, (tGATT_SR_MSG *) &p_tcb->payload_size)) != NULL)
        {
            attp_send_sr_msg (p_tcb, p_buf);

            /* Notify all registered applicaiton with new MTU size. Us a transaction ID */
            /* of 0, as no response is allowed from applcations                    */

            for (i = 0; i < GATT_MAX_APPS; i ++)
            {
                if (gatt_cb.cl_rcb[i].in_use )
                {
                    conn_id = GATT_CREATE_CONN_ID(p_tcb->tcb_idx, gatt_cb.cl_rcb[i].gatt_if);
                    gatt_sr_send_req_callback(conn_id, 0, GATTS_REQ_TYPE_MTU,
                                              (tGATTS_DATA *)&p_tcb->payload_size);
                }
            }

        }
    }
}

/*******************************************************************************
**
** Function         gatts_process_read_by_type_req
**
** Description      process Read By type request.
**                  This PDU can be used to perform:
**                  - read characteristic value
**                  - read characteristic descriptor value
**                  - discover characteristic
**                  - discover characteristic by UUID
**                  - relationship discovery
**
** Returns          void
**
*******************************************************************************/
void gatts_process_read_by_type_req(tGATT_TCB *p_tcb, UINT8 op_code, UINT16 len, UINT8 *p_data)
{
    tBT_UUID            uuid;
    tGATT_SR_REG        *p_rcb;
    UINT16              msg_len = (UINT16)(sizeof(BT_HDR) + p_tcb->payload_size + L2CAP_MIN_OFFSET),
                                  buf_len,
                                  s_hdl, e_hdl, err_hdl = 0;
    BT_HDR              *p_msg = NULL;
    tGATT_STATUS        reason, ret;
    UINT8               *p;
    UINT8               sec_flag, key_size;
    tGATT_SRV_LIST_INFO *p_list= &gatt_cb.srv_list_info;
    tGATT_SRV_LIST_ELEM  *p_srv=NULL;

    reason = gatts_validate_packet_format(op_code, &len, &p_data, &uuid, &s_hdl, &e_hdl);

#if GATT_CONFORMANCE_TESTING == TRUE
    if (gatt_cb.enable_err_rsp && gatt_cb.req_op_code == op_code)
    {
        GATT_TRACE_DEBUG1("Conformance tst: forced err rsp for ReadByType: error status=%d", gatt_cb.err_status);

        gatt_send_error_rsp (p_tcb, gatt_cb.err_status, gatt_cb.req_op_code, s_hdl, FALSE);

        return;
    }
#endif

    if (reason == GATT_SUCCESS)
    {
        if ((p_msg =  (BT_HDR *)GKI_getbuf(msg_len)) == NULL)
        {
            GATT_TRACE_ERROR0("gatts_process_find_info failed. no resources.");

            reason = GATT_NO_RESOURCES;
        }
        else
        {
            memset(p_msg, 0, msg_len);
            p = (UINT8 *)(p_msg + 1) + L2CAP_MIN_OFFSET;

            *p ++ = op_code + 1;
            /* reserve length byte */
            p_msg->len = 2;
            buf_len = p_tcb->payload_size - 2;

            reason = GATT_NOT_FOUND;

            p_srv = p_list->p_first;

            while (p_srv)
            {
                p_rcb = GATT_GET_SR_REG_PTR(p_srv->i_sreg);

                if (p_rcb->in_use &&
                    !(p_rcb->s_hdl > e_hdl ||
                      p_rcb->e_hdl < s_hdl))
                {
                    gatt_sr_get_sec_info(p_tcb->peer_bda,
                                         (BOOLEAN)(p_tcb->att_lcid == L2CAP_ATT_CID),
                                         &sec_flag,
                                         &key_size);

                    ret = gatts_db_read_attr_value_by_type(p_tcb,
                                                           p_rcb->p_db,
                                                           op_code,
                                                           p_msg,
                                                           s_hdl,
                                                           e_hdl,
                                                           uuid,
                                                           &buf_len,
                                                           sec_flag,
                                                           key_size,
                                                           0,
                                                           &err_hdl);
                    if (ret != GATT_NOT_FOUND)
                    {
                        reason = ret;

                        if (ret == GATT_NO_RESOURCES)
                            reason = GATT_SUCCESS;
                    }
                    if (ret != GATT_SUCCESS && ret != GATT_NOT_FOUND)
                    {
                        s_hdl = err_hdl;
                        break;
                    }
                }
                p_srv = p_srv->p_next;
            }
            *p              = (UINT8)p_msg->offset;
            p_msg->offset   = L2CAP_MIN_OFFSET;
        }
    }
    if (reason != GATT_SUCCESS)
    {
        if (p_msg)  GKI_freebuf(p_msg);

        /* in theroy BUSY is not possible(should already been checked), protected check */
        if (reason != GATT_PENDING && reason != GATT_BUSY)
            gatt_send_error_rsp (p_tcb, reason, op_code, s_hdl, FALSE);
    }
    else
        attp_send_sr_msg(p_tcb, p_msg);

}

/*******************************************************************************
**
** Function         gatts_process_write_req
**
** Description      This function is called to process the write request
**                  from client.
**
** Returns          void
**
*******************************************************************************/
void gatts_process_write_req (tGATT_TCB *p_tcb, UINT8 i_rcb, UINT16 handle,
                              UINT8 op_code, UINT16 len, UINT8 *p_data)
{
    tGATTS_DATA     sr_data;
    UINT32          trans_id;
    tGATT_STATUS    status;
    UINT8           sec_flag, key_size, *p = p_data;
    tGATT_SR_REG    *p_sreg;
    UINT16          conn_id;

    memset(&sr_data, 0, sizeof(tGATTS_DATA));

    switch (op_code)
    {
        case GATT_REQ_PREPARE_WRITE:
            sr_data.write_req.is_prep = TRUE;
            STREAM_TO_UINT16(sr_data.write_req.offset, p);
            len -= 2;
            /* fall through */
        case GATT_SIGN_CMD_WRITE:
            if (op_code == GATT_SIGN_CMD_WRITE)
            {
                GATT_TRACE_DEBUG0("Write CMD with data sigining" );
                len -= GATT_AUTH_SIGN_LEN;
            }
            /* fall through */
        case GATT_CMD_WRITE:
        case GATT_REQ_WRITE:
            if (op_code == GATT_REQ_WRITE || op_code == GATT_REQ_PREPARE_WRITE)
                sr_data.write_req.need_rsp = TRUE;
            sr_data.write_req.handle = handle;
            sr_data.write_req.len = len;
            memcpy (sr_data.write_req.value, p, len);
            break;
    }

    gatt_sr_get_sec_info(p_tcb->peer_bda,
                         (BOOLEAN)(p_tcb->att_lcid == L2CAP_ATT_CID),
                         &sec_flag,
                         &key_size);

    status = gatts_write_attr_perm_check (gatt_cb.sr_reg[i_rcb].p_db,
                                          op_code,
                                          handle,
                                          sr_data.write_req.offset,
                                          p,
                                          len,
                                          sec_flag,
                                          key_size);

    if (status == GATT_SUCCESS)
    {
        if ((trans_id = gatt_sr_enqueue_cmd(p_tcb, op_code, handle)) != 0)
        {
            p_sreg = &gatt_cb.sr_reg[i_rcb];
            conn_id = GATT_CREATE_CONN_ID(p_tcb->tcb_idx, p_sreg->gatt_if);
            gatt_sr_send_req_callback(conn_id,
                                      trans_id,
                                      GATTS_REQ_TYPE_WRITE,
                                      &sr_data);

            status = GATT_PENDING;
        }
        else
        {
            GATT_TRACE_ERROR0("max pending command, send error");
            status = GATT_BUSY; /* max pending command, application error */
        }
    }

    /* in theroy BUSY is not possible(should already been checked), protected check */
    if (status != GATT_PENDING && status != GATT_BUSY &&
        (op_code == GATT_REQ_PREPARE_WRITE || op_code == GATT_REQ_WRITE))
    {
        gatt_send_error_rsp (p_tcb, status, op_code, handle, FALSE);
    }
    return;
}

/*******************************************************************************
**
** Function         gatts_process_read_req
**
** Description      This function is called to process the read request
**                  from client.
**
** Returns          void
**
*******************************************************************************/
static void gatts_process_read_req(tGATT_TCB *p_tcb, tGATT_SR_REG *p_rcb, UINT8 op_code,
                                   UINT16 handle, UINT16 len, UINT8 *p_data)
{
    UINT16          buf_len = (UINT16)(sizeof(BT_HDR) + p_tcb->payload_size + L2CAP_MIN_OFFSET);
    tGATT_STATUS    reason;
    BT_HDR          *p_msg = NULL;
    UINT8           sec_flag, key_size, *p;
    UINT16          offset = 0, value_len = 0;

    if ((p_msg =  (BT_HDR *)GKI_getbuf(buf_len)) == NULL)
    {
        GATT_TRACE_ERROR0("gatts_process_find_info failed. no resources.");

        reason = GATT_NO_RESOURCES;
    }
    else
    {
        if (op_code == GATT_REQ_READ_BLOB)
            STREAM_TO_UINT16(offset, p_data);

        memset(p_msg, 0, buf_len);
        p = (UINT8 *)(p_msg + 1) + L2CAP_MIN_OFFSET;
        *p ++ = op_code + 1;
        p_msg->len = 1;
        buf_len = p_tcb->payload_size - 1;

        gatt_sr_get_sec_info(p_tcb->peer_bda,
                             (BOOLEAN)(p_tcb->att_lcid == L2CAP_ATT_CID),
                             &sec_flag,
                             &key_size);

        reason = gatts_read_attr_value_by_handle(p_tcb,
                                                 p_rcb->p_db,
                                                 op_code,
                                                 handle,
                                                 offset,
                                                 p,
                                                 &value_len,
                                                 buf_len,
                                                 sec_flag,
                                                 key_size,
                                                 0);

        p_msg->len += value_len;
    }

    if (reason != GATT_SUCCESS)
    {
        if (p_msg)  GKI_freebuf(p_msg);

        /* in theroy BUSY is not possible(should already been checked), protected check */
        if (reason != GATT_PENDING && reason != GATT_BUSY)
            gatt_send_error_rsp (p_tcb, reason, op_code, handle, FALSE);
    }
    else
        attp_send_sr_msg(p_tcb, p_msg);

}

/*******************************************************************************
**
** Function         gatts_process_attribute_req
**
** Description      This function is called to process the per attribute handle request
**                  from client.
**
** Returns          void
**
*******************************************************************************/
void gatts_process_attribute_req (tGATT_TCB *p_tcb, UINT8 op_code,
                                  UINT16 len, UINT8 *p_data)
{
    UINT16          handle = 0;
    UINT8           *p = p_data, i;
    tGATT_SR_REG    *p_rcb = gatt_cb.sr_reg;
    tGATT_STATUS    status = GATT_INVALID_HANDLE;
    tGATT_ATTR16    *p_attr;

    if (len < 2)
    {
        GATT_TRACE_ERROR0("Illegal PDU length, discard request");
        status = GATT_INVALID_PDU;
    }
    else
    {
        STREAM_TO_UINT16(handle, p);
        len -= 2;
    }

#if GATT_CONFORMANCE_TESTING == TRUE
    gatt_cb.handle = handle;
    if (gatt_cb.enable_err_rsp && gatt_cb.req_op_code == op_code)
    {
        GATT_TRACE_DEBUG1("Conformance tst: forced err rsp: error status=%d", gatt_cb.err_status);

        gatt_send_error_rsp (p_tcb, gatt_cb.err_status, gatt_cb.req_op_code, handle, FALSE);

        return;
    }
#endif

    if (GATT_HANDLE_IS_VALID(handle))
    {
        for (i = 0; i < GATT_MAX_SR_PROFILES; i ++, p_rcb ++)
        {
            if (p_rcb->in_use && p_rcb->s_hdl <= handle && p_rcb->e_hdl >= handle)
            {
                p_attr = (tGATT_ATTR16 *)p_rcb->p_db->p_attr_list;

                while (p_attr)
                {
                    if (p_attr->handle == handle)
                    {
                        switch (op_code)
                        {
                            case GATT_REQ_READ: /* read char/char descriptor value */
                            case GATT_REQ_READ_BLOB:
                                gatts_process_read_req(p_tcb, p_rcb, op_code, handle, len, p);
                                break;

                            case GATT_REQ_WRITE: /* write char/char descriptor value */
                            case GATT_CMD_WRITE:
                            case GATT_SIGN_CMD_WRITE:
                            case GATT_REQ_PREPARE_WRITE:
                                gatts_process_write_req(p_tcb, i, handle, op_code, len, p);
                                break;
                            default:
                                break;
                        }
                        status = GATT_SUCCESS;
                        break;
                    }
                    p_attr = (tGATT_ATTR16 *)p_attr->p_next;
                }
                break;
            }
        }
    }

    if (status != GATT_SUCCESS && op_code != GATT_CMD_WRITE && op_code != GATT_SIGN_CMD_WRITE)
        gatt_send_error_rsp (p_tcb, status, op_code, handle, FALSE);
}

/*******************************************************************************
**
** Function         gatts_proc_srv_chg_ind_ack
**
** Description      This function process the service changed indicaiton ACK
**
** Returns          void
**
*******************************************************************************/
static void gatts_proc_srv_chg_ind_ack(tGATT_TCB *p_tcb )
{
    tGATTS_SRV_CHG_REQ  req;
    tGATTS_SRV_CHG      *p_buf = NULL;

    GATT_TRACE_DEBUG0("gatts_proc_srv_chg_ind_ack");

    if ((p_buf = gatt_is_bda_in_the_srv_chg_clt_list(p_tcb->peer_bda)) != NULL)
    {
        GATT_TRACE_DEBUG0("NV update set srv chg = FALSE");
        p_buf->srv_changed = FALSE;
        memcpy(&req.srv_chg, p_buf, sizeof(tGATTS_SRV_CHG));
        if (gatt_cb.cb_info.p_srv_chg_callback)
            (*gatt_cb.cb_info.p_srv_chg_callback)(GATTS_SRV_CHG_CMD_UPDATE_CLIENT,&req, NULL);
    }
}

/*******************************************************************************
**
** Function         gatts_chk_pending_ind
**
** Description      This function check any pending indication needs to be sent if
**                  there is a pending indication then sent the indication
**
** Returns          void
**
*******************************************************************************/
static void gatts_chk_pending_ind(tGATT_TCB *p_tcb )
{
    tGATT_VALUE *p_buf = (tGATT_VALUE *)GKI_getfirst(&p_tcb->pending_ind_q);
    GATT_TRACE_DEBUG0("gatts_chk_pending_ind");

    if (p_buf )
    {
        GATTS_HandleValueIndication (p_buf->conn_id,
                                     p_buf->handle,
                                     p_buf->len,
                                     p_buf->value);
        GKI_freebuf(GKI_remove_from_queue (&p_tcb->pending_ind_q, p_buf));
    }
}

/*******************************************************************************
**
** Function         gatts_proc_ind_ack
**
** Description      This function process the Indication ack
**
** Returns          TRUE continue to process the indication ack by the aaplication
**                  if the ACk is not a Service Changed Indication Ack
**
*******************************************************************************/
static BOOLEAN gatts_proc_ind_ack(tGATT_TCB *p_tcb, UINT16 ack_handle)
{
    BOOLEAN continue_processing = TRUE;

    GATT_TRACE_DEBUG1 ("gatts_proc_ind_ack ack handle=%d", ack_handle);

    if (ack_handle == gatt_cb.handle_of_h_r)
    {
        gatts_proc_srv_chg_ind_ack(p_tcb);
        /* there is no need to inform the application since srv chg is handled internally by GATT */
        continue_processing = FALSE;
    }

    gatts_chk_pending_ind(p_tcb);
    return continue_processing;
}

/*******************************************************************************
**
** Function         gatts_process_value_conf
**
** Description      This function is called to process the handle value confirmation.
**
** Returns          void
**
*******************************************************************************/
void gatts_process_value_conf(tGATT_TCB *p_tcb, UINT8 op_code)
{
    UINT16          handle = p_tcb->indicate_handle;
    UINT32          trans_id;
    UINT8           i;
    tGATT_SR_REG    *p_rcb = gatt_cb.sr_reg;
    BOOLEAN         continue_processing;
    UINT16          conn_id;

    btu_stop_timer (&p_tcb->conf_timer_ent);
    if (GATT_HANDLE_IS_VALID(handle))
    {
        p_tcb->indicate_handle = 0;
        continue_processing = gatts_proc_ind_ack(p_tcb, handle);

        if (continue_processing)
        {
            for (i = 0; i < GATT_MAX_SR_PROFILES; i ++, p_rcb ++)
            {
                if (p_rcb->in_use && p_rcb->s_hdl <= handle && p_rcb->e_hdl >= handle)
                {
                    trans_id = gatt_sr_enqueue_cmd(p_tcb, op_code, handle);
                    conn_id = GATT_CREATE_CONN_ID(p_tcb->tcb_idx, p_rcb->gatt_if);
                    gatt_sr_send_req_callback(conn_id,
                                              trans_id, GATTS_REQ_TYPE_CONF, (tGATTS_DATA *)&handle);
                }
            }
        }
    }
    else
    {
        GATT_TRACE_ERROR0("unexpected handle value confirmation");
    }
}

/*******************************************************************************
**
** Function         gatt_server_handle_client_req
**
** Description      This function is called to handle the client requests to
**                  server.
**
**
** Returns          void
**
*******************************************************************************/
void gatt_server_handle_client_req (tGATT_TCB *p_tcb, UINT8 op_code,
                                    UINT16 len, UINT8 *p_data)
{
    /* there is pending command, discard this one */
    if (!gatt_sr_cmd_empty(p_tcb) && op_code != GATT_HANDLE_VALUE_CONF)
        return;

    /* the size of the message may not be bigger than the local max PDU size*/
    /* The message has to be smaller than the agreed MTU, len does not include op code */
    if (len >= p_tcb->payload_size)
    {
        GATT_TRACE_ERROR2("server receive invalid PDU size:%d pdu size:%d", len + 1, p_tcb->payload_size );
        /* for invalid request expecting response, send it now */
        if (op_code != GATT_CMD_WRITE &&
            op_code != GATT_SIGN_CMD_WRITE &&
            op_code != GATT_HANDLE_VALUE_CONF)
        {
            gatt_send_error_rsp (p_tcb, GATT_INVALID_PDU, op_code, 0, FALSE);
        }
        /* otherwise, ignore the pkt */
    }
    else
    {
        switch (op_code)
        {
            case GATT_REQ_READ_BY_GRP_TYPE: /* discover primary services */
            case GATT_REQ_FIND_TYPE_VALUE: /* discover service by UUID */
                gatts_process_primary_service_req (p_tcb, op_code, len, p_data);
                break;

            case GATT_REQ_FIND_INFO:/* discover char descrptor */
                gatts_process_find_info(p_tcb, op_code, len, p_data);
                break;

            case GATT_REQ_READ_BY_TYPE: /* read characteristic value, char descriptor value */
                /* discover characteristic, discover char by UUID */
                gatts_process_read_by_type_req(p_tcb, op_code, len, p_data);
                break;


            case GATT_REQ_READ: /* read char/char descriptor value */
            case GATT_REQ_READ_BLOB:
            case GATT_REQ_WRITE: /* write char/char descriptor value */
            case GATT_CMD_WRITE:
            case GATT_SIGN_CMD_WRITE:
            case GATT_REQ_PREPARE_WRITE:
                gatts_process_attribute_req (p_tcb, op_code, len, p_data);
                break;

            case GATT_HANDLE_VALUE_CONF:
                gatts_process_value_conf (p_tcb, op_code);
                break;

            case GATT_REQ_MTU:
                gatts_process_mtu_req (p_tcb, len, p_data);
                break;

            case GATT_REQ_EXEC_WRITE:
                gatt_process_exec_write_req (p_tcb, op_code, len, p_data);
                break;

            case GATT_REQ_READ_MULTI:
                gatt_process_read_multi_req (p_tcb, op_code, len, p_data);
                break;

            default:
                break;
        }
    }
}

#endif /* BLE_INCLUDED */