/*
 * ng_l2cap_ulpi.c
 */

/*-
 * Copyright (c) Maksim Yevmenkin <m_evmenkin@yahoo.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Id: ng_l2cap_ulpi.c,v 1.1 2002/11/24 19:47:06 max Exp $
 * $FreeBSD: src/sys/netgraph/bluetooth/l2cap/ng_l2cap_ulpi.c,v 1.5 2005/01/07 01:45:43 imp Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/endian.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/queue.h>
#include <netgraph7/ng_message.h>
#include <netgraph7/netgraph.h>
#include <netgraph7/bluetooth/include/ng_hci.h>
#include <netgraph7/bluetooth/include/ng_l2cap.h>
#include <netgraph7/bluetooth/l2cap/ng_l2cap_var.h>
#include <netgraph7/bluetooth/l2cap/ng_l2cap_cmds.h>
#include <netgraph7/bluetooth/l2cap/ng_l2cap_evnt.h>
#include <netgraph7/bluetooth/l2cap/ng_l2cap_llpi.h>
#include <netgraph7/bluetooth/l2cap/ng_l2cap_ulpi.h>
#include <netgraph7/bluetooth/l2cap/ng_l2cap_misc.h>

/******************************************************************************
 ******************************************************************************
 **                 Upper Layer Protocol Interface module
 ******************************************************************************
 ******************************************************************************/

/*
 * Process L2CA_Connect request from the upper layer protocol.
 */

int
ng_l2cap_l2ca_con_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_con_ip    *ip = NULL;
        ng_l2cap_con_p           con = NULL;
        ng_l2cap_chan_p          ch = NULL;
        ng_l2cap_cmd_p           cmd = NULL;
        int                      error = 0;

        /* Check message */
        if (msg->header.arglen != sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - invalid L2CA_Connect request message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);
                error = EMSGSIZE;
                goto out;
        }

        ip = (ng_l2cap_l2ca_con_ip *)(msg->data);

        /* Check if we have connection to the remote unit */
        con = ng_l2cap_con_by_addr(l2cap, &ip->bdaddr);
        if (con == NULL) {
                /* Submit LP_ConnectReq to the lower layer */
                error = ng_l2cap_lp_con_req(l2cap, &ip->bdaddr);
                if (error != 0) {
                        NG_L2CAP_ERR(
"%s: %s - unable to send LP_ConnectReq message, error=%d\n",
                                __func__, NG_NODE_NAME(l2cap->node), error);
                        goto out;
                }

                /* This should not fail */
                con = ng_l2cap_con_by_addr(l2cap, &ip->bdaddr);
                KASSERT((con != NULL),
("%s: %s - could not find connection!\n", __func__, NG_NODE_NAME(l2cap->node)));
        }

        /*
         * Create new empty channel descriptor. In case of any failure do 
         * not touch connection descriptor.
         */

        ch = ng_l2cap_new_chan(l2cap, con, ip->psm);
        if (ch == NULL) {
                error = ENOMEM;
                goto out;
        }

        /* Now create L2CAP_ConnectReq command */
        cmd = ng_l2cap_new_cmd(ch->con, ch, ng_l2cap_get_ident(con),
                        NG_L2CAP_CON_REQ, msg->header.token);
        if (cmd == NULL) {
                ng_l2cap_free_chan(ch);
                error = ENOMEM;
                goto out;
        }

        if (cmd->ident == NG_L2CAP_NULL_IDENT) {
                ng_l2cap_free_cmd(cmd);
                ng_l2cap_free_chan(ch);
                error = EIO;
                goto out;
        }

        /* Create L2CAP command packet */
        _ng_l2cap_con_req(cmd->aux, cmd->ident, ch->psm, ch->scid);
        if (cmd->aux == NULL) {
                ng_l2cap_free_cmd(cmd);
                ng_l2cap_free_chan(ch);
                error = ENOBUFS;
                goto out;
        }

        ch->state = NG_L2CAP_W4_L2CAP_CON_RSP;

        /* Link command to the queue */
        ng_l2cap_link_cmd(ch->con, cmd);
        ng_l2cap_lp_deliver(ch->con);
out:
        return (error);
} /* ng_l2cap_l2ca_con_req */

/*
 * Send L2CA_Connect response to the upper layer protocol.
 */

int
ng_l2cap_l2ca_con_rsp(ng_l2cap_chan_p ch, u_int32_t token, u_int16_t result,
                u_int16_t status)
{
        ng_l2cap_p               l2cap = ch->con->l2cap;
        struct ng_mesg          *msg = NULL;
        ng_l2cap_l2ca_con_op    *op = NULL;
        int                      error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_Connect response message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_Connect response message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_CON,
                sizeof(*op), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_con_op *)(msg->data);
                
                /*
                 * XXX Spec. says we should only populate LCID when result == 0
                 * What about PENDING? What the heck, for now always populate
                 * LCID :)
                 */

                op->lcid = ch->scid;
                op->result = result;
                op->status = status;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_con_rsp */

/*
 * Process L2CA_ConnectRsp request from the upper layer protocol.
 */

int
ng_l2cap_l2ca_con_rsp_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_con_rsp_ip        *ip = NULL;
        ng_l2cap_con_p                   con = NULL;
        ng_l2cap_chan_p                  ch = NULL;
        ng_l2cap_cmd_p                   cmd = NULL;
        u_int16_t                        dcid;
        int                              error = 0;

        /* Check message */
        if (msg->header.arglen != sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - invalid L2CA_ConnectRsp request message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);
                error = EMSGSIZE;
                goto out;
        }

        ip = (ng_l2cap_l2ca_con_rsp_ip *)(msg->data);

        /* Check if we have this channel */
        ch = ng_l2cap_chan_by_scid(l2cap, ip->lcid);
        if (ch == NULL) {
                NG_L2CAP_ALERT(
"%s: %s - unexpected L2CA_ConnectRsp request message. " \
"Channel does not exist, lcid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ip->lcid);
                error = ENOENT;
                goto out;
        }

        /* Check channel state */
        if (ch->state != NG_L2CAP_W4_L2CA_CON_RSP) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CA_ConnectRsp request message. " \
"Invalid channel state, state=%d, lcid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->state,
                        ip->lcid);
                error = EINVAL;
                goto out;
        }

        dcid = ch->dcid;
        con = ch->con;

        /*
         * Now we are pretty much sure it is our response. So create and send 
         * L2CAP_ConnectRsp message to our peer.
         */

        if (ch->ident != ip->ident)
                NG_L2CAP_WARN(
"%s: %s - channel ident and response ident do not match, scid=%d, ident=%d. " \
"Will use response ident=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->scid, 
                        ch->ident, ip->ident);

        /* Check result */
        switch (ip->result) {
        case NG_L2CAP_SUCCESS:
                ch->state = NG_L2CAP_CONFIG;
                ch->cfg_state = 0;
                break;

        case NG_L2CAP_PENDING:
                break;

        default:
                ng_l2cap_free_chan(ch);
                ch = NULL;
                break;
        }

        /* Create L2CAP command */
        cmd = ng_l2cap_new_cmd(con, ch, ip->ident, NG_L2CAP_CON_RSP,
                        msg->header.token);
        if (cmd == NULL) {
                if (ch != NULL)
                        ng_l2cap_free_chan(ch);

                error = ENOMEM;
                goto out;
        }

        _ng_l2cap_con_rsp(cmd->aux, cmd->ident, ip->lcid, dcid, 
                ip->result, ip->status);
        if (cmd->aux == NULL) {
                if (ch != NULL)
                        ng_l2cap_free_chan(ch);

                ng_l2cap_free_cmd(cmd);
                error = ENOBUFS;
                goto out;
        } 

        /* Link command to the queue */
        ng_l2cap_link_cmd(con, cmd);
        ng_l2cap_lp_deliver(con);
out:
        return (error);
} /* ng_l2cap_l2ca_con_rsp_req */

/*
 * Send L2CAP_ConnectRsp response to the upper layer
 */
 
int
ng_l2cap_l2ca_con_rsp_rsp(ng_l2cap_chan_p ch, u_int32_t token, u_int16_t result)
{
        ng_l2cap_p                       l2cap = ch->con->l2cap;
        struct ng_mesg                  *msg = NULL;
        ng_l2cap_l2ca_con_rsp_op        *op = NULL;
        int                              error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_ConnectRsp response message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_ConnectRsp response message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_CON_RSP,
                sizeof(*op), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_con_rsp_op *)(msg->data);
                op->result = result;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_con_rsp_rsp */

/*
 * Send L2CA_ConnectInd message to the upper layer protocol. 
 */

int
ng_l2cap_l2ca_con_ind(ng_l2cap_chan_p ch)
{
        ng_l2cap_p                       l2cap = ch->con->l2cap;
        struct ng_mesg                  *msg = NULL;
        ng_l2cap_l2ca_con_ind_ip        *ip = NULL;
        int                              error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_ConnectInd message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_ConnectInd message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_CON_IND,
                sizeof(*ip), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                ip = (ng_l2cap_l2ca_con_ind_ip *)(msg->data);

                bcopy(&ch->con->remote, &ip->bdaddr, sizeof(ip->bdaddr));
                ip->lcid = ch->scid;
                ip->psm = ch->psm;
                ip->ident = ch->ident;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_con_ind */

/*
 * Process L2CA_Config request from the upper layer protocol
 */

int
ng_l2cap_l2ca_cfg_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_cfg_ip    *ip = NULL;
        ng_l2cap_chan_p          ch = NULL;
        ng_l2cap_cmd_p           cmd = NULL;
        struct mbuf             *opt = NULL;
        u_int16_t               *mtu = NULL, *flush_timo = NULL;
        ng_l2cap_flow_p          flow = NULL;
        int                      error = 0;

        /* Check message */
        if (msg->header.arglen != sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - Invalid L2CA_Config request message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);
                error = EMSGSIZE;
                goto out;
        }

        ip = (ng_l2cap_l2ca_cfg_ip *)(msg->data);

        /* Check if we have this channel */
        ch = ng_l2cap_chan_by_scid(l2cap, ip->lcid);
        if (ch == NULL) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CA_Config request message. " \
"Channel does not exist, lcid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ip->lcid);
                error = ENOENT;
                goto out;
        }

        /* Check channel state */
        if (ch->state != NG_L2CAP_OPEN && ch->state != NG_L2CAP_CONFIG) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CA_Config request message. " \
"Invalid channel state, state=%d, lcid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->state,
                        ch->scid);
                error = EINVAL;
                goto out;
        }

        /* Set requested channel configuration options */
        ch->imtu = ip->imtu;
        bcopy(&ip->oflow, &ch->oflow, sizeof(ch->oflow));
        ch->flush_timo = ip->flush_timo;
        ch->link_timo = ip->link_timo;

        /* Compare channel settings with defaults */
        if (ch->imtu != NG_L2CAP_MTU_DEFAULT)
                mtu = &ch->imtu;
        if (ch->flush_timo != NG_L2CAP_FLUSH_TIMO_DEFAULT)
                flush_timo = &ch->flush_timo;
        if (bcmp(ng_l2cap_default_flow(), &ch->oflow, sizeof(ch->oflow)) != 0)
                flow = &ch->oflow;

        /* Create configuration options */
        _ng_l2cap_build_cfg_options(opt, mtu, flush_timo, flow);
        if (opt == NULL) {
                error = ENOBUFS;
                goto out;
        }

        /* Create L2CAP command descriptor */
        cmd = ng_l2cap_new_cmd(ch->con, ch, ng_l2cap_get_ident(ch->con),
                        NG_L2CAP_CFG_REQ, msg->header.token);
        if (cmd == NULL) {
                NG_FREE_M(opt);
                error = ENOMEM;
                goto out;
        }

        if (cmd->ident == NG_L2CAP_NULL_IDENT) {
                ng_l2cap_free_cmd(cmd);
                NG_FREE_M(opt);
                error = EIO;
                goto out;
        }

        /* Create L2CAP command packet */
        _ng_l2cap_cfg_req(cmd->aux, cmd->ident, ch->dcid, 0, opt);
        if (cmd->aux == NULL) {
                ng_l2cap_free_cmd(cmd);
                error =  ENOBUFS;
                goto out;
        }

        /* Adjust channel state for re-configuration */
        if (ch->state == NG_L2CAP_OPEN) {
                ch->state = NG_L2CAP_CONFIG;
                ch->cfg_state = 0;
        }

        /* Link command to the queue */
        ng_l2cap_link_cmd(ch->con, cmd);
        ng_l2cap_lp_deliver(ch->con);
out:
        return (error);
} /* ng_l2cap_l2ca_cfg_req */

/*
 * Send L2CA_Config response to the upper layer protocol
 */

int
ng_l2cap_l2ca_cfg_rsp(ng_l2cap_chan_p ch, u_int32_t token, u_int16_t result)
{
        ng_l2cap_p               l2cap = ch->con->l2cap;
        struct ng_mesg          *msg = NULL;
        ng_l2cap_l2ca_cfg_op    *op = NULL;
        int                      error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_Config response message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_Config response message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_CFG,
                sizeof(*op), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_cfg_op *)(msg->data);
                op->result = result;
                op->imtu = ch->imtu;
                bcopy(&ch->oflow, &op->oflow, sizeof(op->oflow));
                op->flush_timo = ch->flush_timo;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);

                if (error == 0 && result == NG_L2CAP_SUCCESS) {
                        ch->cfg_state |= NG_L2CAP_CFG_IN;

                        if (ch->cfg_state == NG_L2CAP_CFG_BOTH)
                                ch->state = NG_L2CAP_OPEN;
                }
        }

        return (error);
} /* ng_l2cap_l2ca_cfg_rsp */

/*
 * Process L2CA_ConfigRsp request from the upper layer protocol
 *
 * XXX XXX XXX
 *
 * NOTE: The Bluetooth specification says that Configuration_Response 
 * (L2CA_ConfigRsp) should be used to issue response to configuration request
 * indication. The minor problem here is L2CAP command ident. We should use 
 * ident from original L2CAP request to make sure our peer can match request
 * and response. For some reason Bluetooth specification does not include
 * ident field into L2CA_ConfigInd and L2CA_ConfigRsp messages. This seems
 * strange to me, because L2CA_ConnectInd and L2CA_ConnectRsp do have ident
 * field. So we should store last known L2CAP request command ident in channel.
 * Also it seems that upper layer can not reject configuration request, as
 * Configuration_Response message does not have status/reason field.
 */

int
ng_l2cap_l2ca_cfg_rsp_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_cfg_rsp_ip        *ip = NULL;
        ng_l2cap_chan_p                  ch = NULL;
        ng_l2cap_cmd_p                   cmd = NULL;
        struct mbuf                     *opt = NULL;
        u_int16_t                       *mtu = NULL;
        ng_l2cap_flow_p                  flow = NULL;
        int                              error = 0;

        /* Check message */
        if (msg->header.arglen != sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - invalid L2CA_ConfigRsp request message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);
                error = EMSGSIZE;
                goto out;
        }

        ip = (ng_l2cap_l2ca_cfg_rsp_ip *)(msg->data);

        /* Check if we have this channel */
        ch = ng_l2cap_chan_by_scid(l2cap, ip->lcid);
        if (ch == NULL) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CA_ConfigRsp request message. " \
"Channel does not exist, lcid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ip->lcid);
                error = ENOENT;
                goto out;
        }

        /* Check channel state */
        if (ch->state != NG_L2CAP_CONFIG) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CA_ConfigRsp request message. " \
"Invalid channel state, state=%d, lcid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->state,
                        ch->scid);
                error = EINVAL;
                goto out;
        }

        /* Set channel settings */
        if (ip->omtu != ch->omtu) {
                ch->omtu = ip->omtu;
                mtu = &ch->omtu;
        }

        if (bcmp(&ip->iflow, &ch->iflow, sizeof(ch->iflow)) != 0) { 
                bcopy(&ip->iflow, &ch->iflow, sizeof(ch->iflow));
                flow = &ch->iflow;
        }

        if (mtu != NULL || flow != NULL) {
                _ng_l2cap_build_cfg_options(opt, mtu, NULL, flow);
                if (opt == NULL) {
                        error = ENOBUFS;
                        goto out;
                }
        }

        /* Create L2CAP command */
        cmd = ng_l2cap_new_cmd(ch->con, ch, ch->ident, NG_L2CAP_CFG_RSP,
                        msg->header.token);
        if (cmd == NULL) {
                NG_FREE_M(opt);
                error = ENOMEM;
                goto out;
        }

        _ng_l2cap_cfg_rsp(cmd->aux,cmd->ident,ch->dcid,0,NG_L2CAP_SUCCESS,opt);
        if (cmd->aux == NULL) {
                ng_l2cap_free_cmd(cmd);
                error = ENOBUFS;
                goto out;
        }

        /* XXX FIXME - not here ??? */
        ch->cfg_state |= NG_L2CAP_CFG_OUT;
        if (ch->cfg_state == NG_L2CAP_CFG_BOTH)
                ch->state = NG_L2CAP_OPEN;

        /* Link command to the queue */
        ng_l2cap_link_cmd(ch->con, cmd);
        ng_l2cap_lp_deliver(ch->con);
out:
        return (error);
} /* ng_l2cap_l2ca_cfg_rsp_req */

/*
 * Send L2CA_ConfigRsp response to the upper layer protocol
 */

int
ng_l2cap_l2ca_cfg_rsp_rsp(ng_l2cap_chan_p ch, u_int32_t token, u_int16_t result)
{
        ng_l2cap_p                       l2cap = ch->con->l2cap;
        struct ng_mesg                  *msg = NULL;
        ng_l2cap_l2ca_cfg_rsp_op        *op = NULL;
        int                              error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_ConfigRsp response message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_ConfigRsp response message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_CFG_RSP,
                sizeof(*op), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_cfg_rsp_op *)(msg->data);
                op->result = result;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_cfg_rsp_rsp */

/*
 * Send L2CA_ConfigInd message to the upper layer protocol
 *
 * XXX XXX XXX
 *
 * NOTE: The Bluetooth specification says that Configuration_Response 
 * (L2CA_ConfigRsp) should be used to issue response to configuration request
 * indication. The minor problem here is L2CAP command ident. We should use 
 * ident from original L2CAP request to make sure our peer can match request
 * and response. For some reason Bluetooth specification does not include
 * ident field into L2CA_ConfigInd and L2CA_ConfigRsp messages. This seems
 * strange to me, because L2CA_ConnectInd and L2CA_ConnectRsp do have ident
 * field. So we should store last known L2CAP request command ident in channel.
 * Also it seems that upper layer can not reject configuration request, as
 * Configuration_Response message does not have status/reason field.
 */

int
ng_l2cap_l2ca_cfg_ind(ng_l2cap_chan_p ch)
{
        ng_l2cap_p                       l2cap = ch->con->l2cap;
        struct ng_mesg                  *msg = NULL;
        ng_l2cap_l2ca_cfg_ind_ip        *ip = NULL;
        int                              error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - Unable to send L2CA_ConfigInd message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_ConnectInd message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_CFG_IND,
                        sizeof(*ip), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                ip = (ng_l2cap_l2ca_cfg_ind_ip *)(msg->data);
                ip->lcid = ch->scid;
                ip->omtu = ch->omtu;
                bcopy(&ch->iflow, &ip->iflow, sizeof(ip->iflow));
                ip->flush_timo = ch->flush_timo;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_cfg_ind */

/*
 * Process L2CA_Write event
 */

int
ng_l2cap_l2ca_write_req(ng_l2cap_p l2cap, struct mbuf *m)
{
        ng_l2cap_l2ca_hdr_t     *l2ca_hdr = NULL;
        ng_l2cap_chan_p          ch = NULL;
        ng_l2cap_cmd_p           cmd = NULL;
        int                      error = 0;
        u_int32_t                token = 0;

        /* Make sure we can access L2CA data packet header */
        if (m->m_pkthdr.len < sizeof(*l2ca_hdr)) {
                NG_L2CAP_ERR(
"%s: %s - L2CA Data packet too small, len=%d\n",
                        __func__,NG_NODE_NAME(l2cap->node),m->m_pkthdr.len);
                error = EMSGSIZE;
                goto drop;
        }

        /* Get L2CA data packet header */
        NG_L2CAP_M_PULLUP(m, sizeof(*l2ca_hdr));
        if (m == NULL)
                return (ENOBUFS);

        l2ca_hdr = mtod(m, ng_l2cap_l2ca_hdr_t *);
        token = l2ca_hdr->token;
        m_adj(m, sizeof(*l2ca_hdr));

        /* Verify payload size */
        if (l2ca_hdr->length != m->m_pkthdr.len) {
                NG_L2CAP_ERR(
"%s: %s - invalid L2CA Data packet. " \
"Payload length does not match, length=%d, len=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), l2ca_hdr->length,
                        m->m_pkthdr.len);
                error = EMSGSIZE;
                goto drop;
        }

        /* Check channel ID */
        if (l2ca_hdr->lcid < NG_L2CAP_FIRST_CID) {
                NG_L2CAP_ERR(
"%s: %s - invalid L2CA Data packet. Invalid channel ID, cid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), l2ca_hdr->lcid);
                error = EINVAL;
                goto drop;
        }

        /* Verify that we have the channel and make sure it is open */
        ch = ng_l2cap_chan_by_scid(l2cap, l2ca_hdr->lcid);
        if (ch == NULL) {
                NG_L2CAP_ERR(
"%s: %s - invalid L2CA Data packet. Channel does not exist, cid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), l2ca_hdr->lcid);
                error = ENOENT;
                goto drop;
        }

        if (ch->state != NG_L2CAP_OPEN) {
                NG_L2CAP_ERR(
"%s: %s - invalid L2CA Data packet. Invalid channel state, scid=%d, state=%d\n",
                         __func__, NG_NODE_NAME(l2cap->node), ch->scid, 
                        ch->state);
                error = EHOSTDOWN;
                goto drop; /* XXX not always - re-configure */
        }

        /* Create L2CAP command descriptor */
        cmd = ng_l2cap_new_cmd(ch->con, ch, 0, NGM_L2CAP_L2CA_WRITE, token);
        if (cmd == NULL) {
                error = ENOMEM;
                goto drop;
        }

        /* Attach data packet and link command to the queue */
        cmd->aux = m;
        ng_l2cap_link_cmd(ch->con, cmd);
        ng_l2cap_lp_deliver(ch->con);

        return (error);
drop:
        NG_FREE_M(m);

        return (error);
} /* ng_l2cap_l2ca_write_req */

/*
 * Send L2CA_Write response
 */

int
ng_l2cap_l2ca_write_rsp(ng_l2cap_chan_p ch, u_int32_t token, u_int16_t result,
                u_int16_t length)
{
        ng_l2cap_p               l2cap = ch->con->l2cap;
        struct ng_mesg          *msg = NULL;
        ng_l2cap_l2ca_write_op  *op = NULL;
        int                      error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_WriteRsp message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_WriteRsp message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_WRITE,
                        sizeof(*op), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_write_op *)(msg->data);
                op->result = result;
                op->length = length;
                op->lcid   = ch->scid;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_write_rsp */

/*
 * Receive packet from the lower layer protocol and send it to the upper
 * layer protocol (L2CAP_Read)
 */

int
ng_l2cap_l2ca_receive(ng_l2cap_con_p con)
{
        ng_l2cap_p       l2cap = con->l2cap;
        ng_l2cap_hdr_t  *hdr = NULL;
        ng_l2cap_chan_p  ch = NULL;
        int              error = 0;

        NG_L2CAP_M_PULLUP(con->rx_pkt, sizeof(*hdr));
        if (con->rx_pkt == NULL)
                return (ENOBUFS);

        hdr = mtod(con->rx_pkt, ng_l2cap_hdr_t *);

        /* Check channel */
        ch = ng_l2cap_chan_by_scid(l2cap, hdr->dcid);
        if (ch == NULL) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CAP data packet. Channel does not exist, cid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), hdr->dcid);
                error = ENOENT;
                goto drop;
        }

        /* Check channel state */
        if (ch->state != NG_L2CAP_OPEN) {
                NG_L2CAP_WARN(
"%s: %s - unexpected L2CAP data packet. " \
"Invalid channel state, cid=%d, state=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->scid,
                        ch->state);
                error = EHOSTDOWN; /* XXX not always - re-configuration */
                goto drop;
        }

        /* Check payload size and channel's MTU */
        if (hdr->length > ch->imtu) {
                NG_L2CAP_ERR(
"%s: %s - invalid L2CAP data packet. " \
"Packet too big, length=%d, imtu=%d, cid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), hdr->length, 
                        ch->imtu, ch->scid);
                error = EMSGSIZE;
                goto drop;
        }

        /*
         * If we got here then everything looks good and we can sent packet
         * to the upper layer protocol.
         */

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CAP data packet. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);
                error = ENOTCONN;
                goto drop;
        }

        NG_SEND_DATA_ONLY(error, l2cap->l2c, con->rx_pkt);
        con->rx_pkt = NULL;
drop:
        NG_FREE_M(con->rx_pkt); /* checks for != NULL */

        return (error);
} /* ng_l2cap_receive */

/*
 * Receive connectioless (multicast) packet from the lower layer protocol and 
 * send it to the upper layer protocol
 */

int
ng_l2cap_l2ca_clt_receive(ng_l2cap_con_p con)
{
        struct _clt_pkt {
                ng_l2cap_hdr_t           h;
                ng_l2cap_clt_hdr_t       c_h;
        } __attribute__ ((packed))      *hdr = NULL;
        ng_l2cap_p                       l2cap = con->l2cap;
        int                              length, error = 0;

        NG_L2CAP_M_PULLUP(con->rx_pkt, sizeof(*hdr));
        if (con->rx_pkt == NULL)
                return (ENOBUFS);

        hdr = mtod(con->rx_pkt, struct _clt_pkt *);

        /* Check packet */
        length = con->rx_pkt->m_pkthdr.len - sizeof(*hdr);
        if (length < 0) {
                NG_L2CAP_ERR(
"%s: %s - invalid L2CAP CLT data packet. Packet too small, length=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), length);
                error = EMSGSIZE;
                goto drop;
        }

        /* Check payload size against CLT MTU */
        if (length > NG_L2CAP_MTU_DEFAULT) {
                NG_L2CAP_ERR(
"%s: %s - invalid L2CAP CLT data packet. Packet too big, length=%d, mtu=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), length,
                        NG_L2CAP_MTU_DEFAULT);
                error = EMSGSIZE;
                goto drop;
        }

        hdr->c_h.psm = le16toh(hdr->c_h.psm);

        /*
         * If we got here then everything looks good and we can sent packet
         * to the upper layer protocol.
         */

        /* Select upstream hook based on PSM */
        switch (hdr->c_h.psm) {
        case NG_L2CAP_PSM_SDP:
                if (l2cap->flags & NG_L2CAP_CLT_SDP_DISABLED)
                        goto drop;
                break;

        case NG_L2CAP_PSM_RFCOMM:
                if (l2cap->flags & NG_L2CAP_CLT_RFCOMM_DISABLED)
                        goto drop;
                break;

        case NG_L2CAP_PSM_TCP:
                if (l2cap->flags & NG_L2CAP_CLT_TCP_DISABLED)
                        goto drop;
                break;
        }

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CAP CLT data packet. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), hdr->c_h.psm);
                error = ENOTCONN;
                goto drop;
        }

        NG_SEND_DATA_ONLY(error, l2cap->l2c, con->rx_pkt);
        con->rx_pkt = NULL;
drop:
        NG_FREE_M(con->rx_pkt); /* checks for != NULL */

        return (error);
} /* ng_l2cap_l2ca_clt_receive */

/*
 * Send L2CA_QoSViolationInd to the upper layer protocol
 */

int
ng_l2cap_l2ca_qos_ind(ng_l2cap_chan_p ch)
{
        ng_l2cap_p                       l2cap = ch->con->l2cap;
        struct ng_mesg                  *msg = NULL;
        ng_l2cap_l2ca_qos_ind_ip        *ip = NULL;
        int                              error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_QoSViolationInd message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_QoSViolationInd message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_QOS_IND,
                sizeof(*ip), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                ip = (ng_l2cap_l2ca_qos_ind_ip *)(msg->data);
                bcopy(&ch->con->remote, &ip->bdaddr, sizeof(ip->bdaddr));
                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_qos_ind */

/*
 * Process L2CA_Disconnect request from the upper layer protocol.
 */

int
ng_l2cap_l2ca_discon_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_discon_ip *ip = NULL;
        ng_l2cap_chan_p          ch = NULL;
        ng_l2cap_cmd_p           cmd = NULL;
        int                      error = 0;

        /* Check message */
        if (msg->header.arglen != sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - invalid L2CA_Disconnect request message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);
                error = EMSGSIZE;
                goto out;
        }

        ip = (ng_l2cap_l2ca_discon_ip *)(msg->data);

        /* Check if we have this channel */
        ch = ng_l2cap_chan_by_scid(l2cap, ip->lcid);
        if (ch == NULL) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CA_Disconnect request message. " \
"Channel does not exist, lcid=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ip->lcid);
                error = ENOENT;
                goto out;
        }

        /* Check channel state */
        if (ch->state != NG_L2CAP_CONFIG && ch->state != NG_L2CAP_OPEN && 
            ch->state != NG_L2CAP_W4_L2CAP_DISCON_RSP) {
                NG_L2CAP_ERR(
"%s: %s - unexpected L2CA_Disconnect request message. " \
"Invalid channel state, state=%d, lcid=%d\n", 
                        __func__, NG_NODE_NAME(l2cap->node), ch->state,
                        ch->scid);
                error = EINVAL;
                goto out;
        }

        /* Create and send L2CAP_DisconReq message */
        cmd = ng_l2cap_new_cmd(ch->con, ch, ng_l2cap_get_ident(ch->con),
                        NG_L2CAP_DISCON_REQ, msg->header.token);
        if (cmd == NULL) {
                ng_l2cap_free_chan(ch);
                error = ENOMEM;
                goto out;
        }

        if (cmd->ident == NG_L2CAP_NULL_IDENT) {
                ng_l2cap_free_chan(ch);
                ng_l2cap_free_cmd(cmd);
                error = EIO;
                goto out;
        }

        _ng_l2cap_discon_req(cmd->aux, cmd->ident, ch->dcid, ch->scid);
        if (cmd->aux == NULL) {
                ng_l2cap_free_chan(ch);
                ng_l2cap_free_cmd(cmd);
                error = ENOBUFS;
                goto out;
        }

        ch->state = NG_L2CAP_W4_L2CAP_DISCON_RSP;

        /* Link command to the queue */
        ng_l2cap_link_cmd(ch->con, cmd);
        ng_l2cap_lp_deliver(ch->con);
out:
        return (error);
} /* ng_l2cap_l2ca_discon_req */

/*
 * Send L2CA_Disconnect response to the upper layer protocol
 */

int
ng_l2cap_l2ca_discon_rsp(ng_l2cap_chan_p ch, u_int32_t token, u_int16_t result)
{
        ng_l2cap_p               l2cap = ch->con->l2cap;
        struct ng_mesg          *msg = NULL;
        ng_l2cap_l2ca_discon_op *op = NULL;
        int                      error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_Disconnect response message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_Disconnect response message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_DISCON,
                sizeof(*op), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_discon_op *)(msg->data);
                op->result = result;

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        }

        return (error);
} /* ng_l2cap_l2ca_discon_rsp */

/*
 * Send L2CA_DisconnectInd message to the upper layer protocol.
 */

int
ng_l2cap_l2ca_discon_ind(ng_l2cap_chan_p ch)
{
        ng_l2cap_p                       l2cap = ch->con->l2cap;
        struct ng_mesg                  *msg = NULL;
        ng_l2cap_l2ca_discon_ind_ip     *ip = NULL;
        int                              error = 0;

        /* Check if upstream hook is connected and valid */
        if (l2cap->l2c == NULL || NG_HOOK_NOT_VALID(l2cap->l2c)) {
                NG_L2CAP_ERR(
"%s: %s - unable to send L2CA_DisconnectInd message. " \
"Hook is not connected or valid, psm=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ch->psm);

                return (ENOTCONN);
        }

        /* Create and send L2CA_DisconnectInd message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_DISCON_IND,
                sizeof(*ip), M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                ip = (ng_l2cap_l2ca_discon_ind_ip *)(msg->data);
                ip->lcid = ch->scid;
                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->l2c, 0);
        } 

        return (error);
} /* ng_l2cap_l2ca_discon_ind */

/*
 * Process L2CA_GroupCreate request from the upper layer protocol.
 * XXX FIXME
 */

int
ng_l2cap_l2ca_grp_create(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        return (ENOTSUP);
} /* ng_l2cap_l2ca_grp_create */

/*
 * Process L2CA_GroupClose request from the upper layer protocol
 * XXX FIXME
 */

int
ng_l2cap_l2ca_grp_close(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        return (ENOTSUP);
} /* ng_l2cap_l2ca_grp_close */

/*
 * Process L2CA_GroupAddMember request from the upper layer protocol.
 * XXX FIXME
 */

int
ng_l2cap_l2ca_grp_add_member_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        return (ENOTSUP);
} /* ng_l2cap_l2ca_grp_add_member_req */

/*
 * Send L2CA_GroupAddMember response to the upper layer protocol.
 * XXX FIXME
 */

int
ng_l2cap_l2ca_grp_add_member_rsp(ng_l2cap_chan_p ch, u_int32_t token,
                u_int16_t result)
{
        return (0);
} /* ng_l2cap_l2ca_grp_add_member_rsp */

/*
 * Process L2CA_GroupDeleteMember request from the upper layer protocol
 * XXX FIXME
 */

int
ng_l2cap_l2ca_grp_rem_member(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        return (ENOTSUP);
} /* ng_l2cap_l2ca_grp_rem_member */

/*
 * Process L2CA_GroupGetMembers request from the upper layer protocol
 * XXX FIXME
 */

int
ng_l2cap_l2ca_grp_get_members(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        return (ENOTSUP);
} /* ng_l2cap_l2ca_grp_get_members */

/*
 * Process L2CA_Ping request from the upper layer protocol
 */

int
ng_l2cap_l2ca_ping_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_ping_ip   *ip = NULL;
        ng_l2cap_con_p           con = NULL;
        ng_l2cap_cmd_p           cmd = NULL;
        int                      error = 0;

        /* Verify message */
        if (msg->header.arglen < sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - invalid L2CA_Ping request message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);
                error = EMSGSIZE;
                goto out;
        }

        ip = (ng_l2cap_l2ca_ping_ip *)(msg->data);
        if (ip->echo_size > NG_L2CAP_MAX_ECHO_SIZE) {
                NG_L2CAP_WARN(
"%s: %s - invalid L2CA_Ping request. Echo size is too big, echo_size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node), ip->echo_size);
                error = EMSGSIZE;
                goto out;
        }

        /* Check if we have connection to the unit */
        con = ng_l2cap_con_by_addr(l2cap, &ip->bdaddr);
        if (con == NULL) {
                /* Submit LP_ConnectReq to the lower layer */
                error = ng_l2cap_lp_con_req(l2cap, &ip->bdaddr);
                if (error != 0) {
                        NG_L2CAP_ERR(
"%s: %s - unable to send LP_ConnectReq message, error=%d\n",
                                __func__, NG_NODE_NAME(l2cap->node), error);
                        goto out;
                }

                /* This should not fail */
                con = ng_l2cap_con_by_addr(l2cap, &ip->bdaddr);
                KASSERT((con != NULL),
("%s: %s - could not find connection!\n", __func__, NG_NODE_NAME(l2cap->node)));
        }

        /* Create L2CAP command descriptor */
        cmd = ng_l2cap_new_cmd(con, NULL, ng_l2cap_get_ident(con),
                        NG_L2CAP_ECHO_REQ, msg->header.token);
        if (cmd == NULL) {
                error = ENOMEM;
                goto out;
        }

        if (cmd->ident == NG_L2CAP_NULL_IDENT) {
                ng_l2cap_free_cmd(cmd);
                error = EIO;
                goto out;
        }

        /* Create L2CAP command packet */
        _ng_l2cap_echo_req(cmd->aux, cmd->ident, 
                        msg->data + sizeof(*ip), ip->echo_size);
        if (cmd->aux == NULL) {
                ng_l2cap_free_cmd(cmd);
                error = ENOBUFS;
                goto out;
        }

        /* Link command to the queue */
        ng_l2cap_link_cmd(con, cmd);
        ng_l2cap_lp_deliver(con);
out:
        return (error);
} /* ng_l2cap_l2ca_ping_req */

/*
 * Send L2CA_Ping response to the upper layer protocol
 */

int
ng_l2cap_l2ca_ping_rsp(ng_l2cap_con_p con, u_int32_t token, u_int16_t result,
                struct mbuf *data)
{
        ng_l2cap_p               l2cap = con->l2cap;
        struct ng_mesg          *msg = NULL;
        ng_l2cap_l2ca_ping_op   *op = NULL;
        int                      error = 0, size = 0;

        /* Check if control hook is connected and valid */
        if (l2cap->ctl == NULL || NG_HOOK_NOT_VALID(l2cap->ctl)) {
                NG_L2CAP_WARN(
"%s: %s - unable to send L2CA_Ping response message. " \
"Hook is not connected or valid\n",
                        __func__, NG_NODE_NAME(l2cap->node));
                error = ENOTCONN;
                goto out;
        }

        size = (data == NULL)? 0 : data->m_pkthdr.len;

        /* Create and send L2CA_Ping response message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_PING,
                sizeof(*op) + size, M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_ping_op *)(msg->data);
                op->result = result;
                bcopy(&con->remote, &op->bdaddr, sizeof(op->bdaddr));
                if (data != NULL && size > 0) {
                        op->echo_size = size;
                        m_copydata(data, 0, size, (caddr_t) op + sizeof(*op));
                }

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->ctl, 0);
        }
out:
        NG_FREE_M(data);

        return (error);
} /* ng_l2cap_l2ca_ping_rsp */

/*
 * Process L2CA_GetInfo request from the upper layer protocol
 */

int
ng_l2cap_l2ca_get_info_req(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_get_info_ip       *ip = NULL;
        ng_l2cap_con_p                   con = NULL;
        ng_l2cap_cmd_p                   cmd = NULL;
        int                              error = 0;

        /* Verify message */
        if (msg->header.arglen != sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - invalid L2CA_GetInfo request message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);
                error = EMSGSIZE;
                goto out;
        }

        ip = (ng_l2cap_l2ca_get_info_ip *)(msg->data);

        /* Check if we have connection to the unit */
        con = ng_l2cap_con_by_addr(l2cap, &ip->bdaddr);
        if (con == NULL) {
                /* Submit LP_ConnectReq to the lower layer */
                error = ng_l2cap_lp_con_req(l2cap, &ip->bdaddr);
                if (error != 0) {
                        NG_L2CAP_ERR(
"%s: %s - unable to send LP_ConnectReq message, error=%d\n",
                                __func__, NG_NODE_NAME(l2cap->node), error);
                        goto out;
                }

                /* This should not fail */
                con = ng_l2cap_con_by_addr(l2cap, &ip->bdaddr);
                KASSERT((con != NULL),
("%s: %s - could not find connection!\n", __func__, NG_NODE_NAME(l2cap->node)));
        }

        /* Create L2CAP command descriptor */
        cmd = ng_l2cap_new_cmd(con, NULL, ng_l2cap_get_ident(con),
                        NG_L2CAP_INFO_REQ, msg->header.token);
        if (cmd == NULL) {
                error = ENOMEM;
                goto out;
        }

        if (cmd->ident == NG_L2CAP_NULL_IDENT) {
                ng_l2cap_free_cmd(cmd);
                error = EIO;
                goto out;
        }

        /* Create L2CAP command packet */
        _ng_l2cap_info_req(cmd->aux, cmd->ident, ip->info_type);
        if (cmd->aux == NULL) {
                ng_l2cap_free_cmd(cmd);
                error = ENOBUFS;
                goto out;
        }

        /* Link command to the queue */
        ng_l2cap_link_cmd(con, cmd);
        ng_l2cap_lp_deliver(con);
out:
        return (error);
} /* ng_l2cap_l2ca_get_info_req */

/*
 * Send L2CA_GetInfo response to the upper layer protocol
 */

int
ng_l2cap_l2ca_get_info_rsp(ng_l2cap_con_p con, u_int32_t token, 
                u_int16_t result, struct mbuf *data)
{
        ng_l2cap_p                       l2cap = con->l2cap;
        struct ng_mesg                  *msg = NULL;
        ng_l2cap_l2ca_get_info_op       *op = NULL;
        int                              error = 0, size;

        /* Check if control hook is connected and valid */
        if (l2cap->ctl == NULL || NG_HOOK_NOT_VALID(l2cap->ctl)) {
                NG_L2CAP_WARN(
"%s: %s - unable to send L2CA_GetInfo response message. " \
"Hook is not connected or valid\n",
                        __func__, NG_NODE_NAME(l2cap->node));
                error = ENOTCONN;
                goto out;
        }

        size = (data == NULL)? 0 : data->m_pkthdr.len;

        /* Create and send L2CA_GetInfo response message */
        NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_GET_INFO,
                sizeof(*op) + size, M_WAITOK | M_NULLOK);
        if (msg == NULL)
                error = ENOMEM;
        else {
                msg->header.token = token;
                msg->header.flags |= NGF_RESP;

                op = (ng_l2cap_l2ca_get_info_op *)(msg->data);
                op->result = result;
                if (data != NULL && size > 0) {
                        op->info_size = size;
                        m_copydata(data, 0, size, (caddr_t) op + sizeof(*op));
                }

                NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->ctl, 0);
        }
out:
        NG_FREE_M(data);

        return (error);
} /* ng_l2cap_l2ca_get_info_rsp */
        
/*
 * Process L2CA_EnableCLT message from the upper layer protocol
 * XXX convert to NGN_L2CAP_NODE_SET_FLAGS?
 */

int
ng_l2cap_l2ca_enable_clt(ng_l2cap_p l2cap, struct ng_mesg *msg)
{
        ng_l2cap_l2ca_enable_clt_ip     *ip = NULL;
        int                              error = 0;
#if 0
 *      ng_l2cap_l2ca_enable_clt_op     *op = NULL;
 *      u_int16_t                        result; 
 *      u_int32_t                        token;
#endif

        /* Check message */
        if (msg->header.arglen != sizeof(*ip)) {
                NG_L2CAP_ALERT(
"%s: %s - invalid L2CA_EnableCLT message size, size=%d\n",
                        __func__, NG_NODE_NAME(l2cap->node),
                        msg->header.arglen);

                return (EMSGSIZE);
        }

        /* Process request */
        ip = (ng_l2cap_l2ca_enable_clt_ip *) (msg->data);
#if 0
 *      result = NG_L2CAP_SUCCESS;
#endif

        switch (ip->psm) 
        {
        case 0:
                /* Special case: disable/enable all PSM */
                if (ip->enable)
                        l2cap->flags &= ~(NG_L2CAP_CLT_SDP_DISABLED    |
                                          NG_L2CAP_CLT_RFCOMM_DISABLED |
                                          NG_L2CAP_CLT_TCP_DISABLED);
                else
                        l2cap->flags |= (NG_L2CAP_CLT_SDP_DISABLED    |
                                         NG_L2CAP_CLT_RFCOMM_DISABLED |
                                         NG_L2CAP_CLT_TCP_DISABLED);
                break;

        case NG_L2CAP_PSM_SDP:
                if (ip->enable)
                        l2cap->flags &= ~NG_L2CAP_CLT_SDP_DISABLED;
                else
                        l2cap->flags |= NG_L2CAP_CLT_SDP_DISABLED;
                break;

        case NG_L2CAP_PSM_RFCOMM:
                if (ip->enable)
                        l2cap->flags &= ~NG_L2CAP_CLT_RFCOMM_DISABLED;
                else
                        l2cap->flags |= NG_L2CAP_CLT_RFCOMM_DISABLED;
                break;

        case NG_L2CAP_PSM_TCP:
                if (ip->enable)
                        l2cap->flags &= ~NG_L2CAP_CLT_TCP_DISABLED;
                else
                        l2cap->flags |= NG_L2CAP_CLT_TCP_DISABLED;
                break;
        
        default:
                NG_L2CAP_ERR(
"%s: %s - unsupported PSM=%d\n", __func__, NG_NODE_NAME(l2cap->node), ip->psm);
#if 0
 *              result = NG_L2CAP_PSM_NOT_SUPPORTED;
#endif
                error = ENOTSUP;
                break;
        }

#if 0
 *      /* Create and send response message */
 *      token = msg->header.token;
 *      NG_FREE_MSG(msg);
 *      NG_MKMESSAGE(msg, NGM_L2CAP_COOKIE, NGM_L2CAP_L2CA_ENABLE_CLT,
 *              sizeof(*op), M_WAITOK | M_NULLOK);
 *      if (msg == NULL)
 *              error = ENOMEM;
 *      else {
 *              msg->header.token = token;
 *              msg->header.flags |= NGF_RESP;
 * 
 *              op = (ng_l2cap_l2ca_enable_clt_op *)(msg->data);
 *              op->result = result;
 *      }
 * 
 *      /* Send response to control hook */
 *      if (l2cap->ctl != NULL && NG_HOOK_IS_VALID(l2cap->ctl))
 *              NG_SEND_MSG_HOOK(error, l2cap->node, msg, l2cap->ctl, 0);
#endif

        return (error);
} /* ng_l2cap_l2ca_enable_clt */