irlan_common.c

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/*********************************************************************
 *                
 * Filename:      irlan_common.c
 * Version:       0.9
 * Description:   IrDA LAN Access Protocol Implementation
 * Status:        Experimental.
 * Author:        Dag Brattli <dagb@cs.uit.no>
 * Created at:    Sun Aug 31 20:14:37 1997
 * Modified at:   Fri Apr 21 14:55:31 2000
 * Modified by:   Dag Brattli <dagb@cs.uit.no>
 * 
 *     Copyright (c) 1997, 1999-2000 Dag Brattli <dagb@cs.uit.no>, 
 *     All Rights Reserved.
 *     
 *     This program is free software; you can redistribute it and/or 
 *     modify it under the terms of the GNU General Public License as 
 *     published by the Free Software Foundation; either version 2 of 
 *     the License, or (at your option) any later version.
 *
 *     Neither Dag Brattli nor University of Tromsø admit liability nor
 *     provide warranty for any of this software. This material is 
 *     provided "AS-IS" and at no charge.
 *
 ********************************************************************/

#include <linux/config.h>
#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/proc_fs.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>

#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/byteorder.h>

#include <net/irda/irda.h>
#include <net/irda/irttp.h>
#include <net/irda/irlmp.h>
#include <net/irda/iriap.h>
#include <net/irda/timer.h>

#include <net/irda/irlan_common.h>
#include <net/irda/irlan_client.h>
#include <net/irda/irlan_provider.h> 
#include <net/irda/irlan_eth.h>
#include <net/irda/irlan_filter.h>

/* 
 * Send gratuitous ARP when connected to a new AP or not. May be a clever
 * thing to do, but for some reason the machine crashes if you use DHCP. So
 * lets not use it by default.
 */
#undef CONFIG_IRLAN_SEND_GRATUITOUS_ARP

/* extern char sysctl_devname[]; */

/*
 *  Master structure
 */
hashbin_t *irlan = NULL;
static __u32 ckey, skey;

/* Module parameters */
static int eth = 0; /* Use "eth" or "irlan" name for devices */
static int access = ACCESS_PEER; /* PEER, DIRECT or HOSTED */

static char *irlan_state[] = {
        "IRLAN_IDLE",
        "IRLAN_QUERY",
        "IRLAN_CONN",
        "IRLAN_INFO",
        "IRLAN_MEDIA",
        "IRLAN_OPEN",
        "IRLAN_WAIT",
        "IRLAN_ARB", 
        "IRLAN_DATA",
        "IRLAN_CLOSE",
        "IRLAN_SYNC"
};

static char *irlan_access[] = {
        "UNKNOWN",
        "DIRECT",
        "PEER",
        "HOSTED"
};

static char *irlan_media[] = {
        "UNKNOWN",
        "802.3",
        "802.5"
};

static void __irlan_close(struct irlan_cb *self);
static int __irlan_insert_param(struct sk_buff *skb, char *param, int type, 
                                __u8 value_byte, __u16 value_short, 
                                __u8 *value_array, __u16 value_len);
void irlan_close_tsaps(struct irlan_cb *self);

#ifdef CONFIG_PROC_FS
static int irlan_proc_read(char *buf, char **start, off_t offset, int len, 
                           int unused);

extern struct proc_dir_entry *proc_irda;
#endif /* CONFIG_PROC_FS */

/*
 * Function irlan_init (void)
 *
 *    Initialize IrLAN layer
 *
 */
int __init irlan_init(void)
{
        struct irlan_cb *new;
        __u16 hints;

        IRDA_DEBUG(4, __FUNCTION__"()\n");

        /* Allocate master structure */
        irlan = hashbin_new(HB_LOCAL); 
        if (irlan == NULL) {
                printk(KERN_WARNING "IrLAN: Can't allocate hashbin!\n");
                return -ENOMEM;
        }
#ifdef CONFIG_PROC_FS
        create_proc_entry("irlan", 0, proc_irda)->get_info = irlan_proc_read;
#endif /* CONFIG_PROC_FS */

        hints = irlmp_service_to_hint(S_LAN);

        /* Register with IrLMP as a client */
        ckey = irlmp_register_client(hints, irlan_client_discovery_indication,
                                     NULL);
        
        /* Register with IrLMP as a service */
        skey = irlmp_register_service(hints);

        /* Start the master IrLAN instance (the only one for now) */
        new = irlan_open(DEV_ADDR_ANY, DEV_ADDR_ANY);

        /* The master will only open its (listen) control TSAP */
        irlan_provider_open_ctrl_tsap(new);

        /* Do some fast discovery! */
        irlmp_discovery_request(DISCOVERY_DEFAULT_SLOTS);

        return 0;
}

void irlan_cleanup(void) 
{
        IRDA_DEBUG(4, __FUNCTION__ "()\n");

        irlmp_unregister_client(ckey);
        irlmp_unregister_service(skey);

#ifdef CONFIG_PROC_FS
        remove_proc_entry("irlan", proc_irda);
#endif /* CONFIG_PROC_FS */
        /*
         *  Delete hashbin and close all irlan client instances in it
         */
        hashbin_delete(irlan, (FREE_FUNC) __irlan_close);
}

/*
 * Function irlan_register_netdev (self)
 *
 *    Registers the network device to be used. We should don't register until
 *    we have been binded to a particular provider or client.
 */
int irlan_register_netdev(struct irlan_cb *self)
{
        int i=0;

        IRDA_DEBUG(0, __FUNCTION__ "()\n");

        /* Check if we should call the device eth<x> or irlan<x> */
        if (!eth) {
                /* Get the first free irlan<x> name */
                do {
                        sprintf(self->ifname, "%s%d", "irlan", i++);
                } while (dev_get(self->ifname));
        }
        self->dev.name = self->ifname;
        
        if (register_netdev(&self->dev) != 0) {
                IRDA_DEBUG(2, __FUNCTION__ "(), register_netdev() failed!\n");
                return -1;
        }
        return 0;
}

/*
 * Function irlan_open (void)
 *
 *    Open new instance of a client/provider, we should only register the 
 *    network device if this instance is ment for a particular client/provider
 */
struct irlan_cb *irlan_open(__u32 saddr, __u32 daddr)
{
        struct irlan_cb *self;

        IRDA_DEBUG(2, __FUNCTION__ "()\n");

        /* 
         *  Initialize the irlan structure. 
         */
        self = kmalloc(sizeof(struct irlan_cb), GFP_ATOMIC);
        if (self == NULL)
                return NULL;
        
        memset(self, 0, sizeof(struct irlan_cb));

        /*
         *  Initialize local device structure
         */
        self->magic = IRLAN_MAGIC;

        ASSERT(irlan != NULL, return NULL;);
        
        sprintf(self->ifname, "%s", "unknown");

        self->dev.priv = (void *) self;
        self->dev.next = NULL;
        self->dev.init = irlan_eth_init;
        
        self->saddr = saddr;
        self->daddr = daddr;

        /* Provider access can only be PEER, DIRECT, or HOSTED */
        self->provider.access_type = access;
        self->media = MEDIA_802_3;

        init_timer(&self->watchdog_timer);
        init_timer(&self->client.kick_timer);

        hashbin_insert(irlan, (queue_t *) self, daddr, NULL);
        
        skb_queue_head_init(&self->client.txq);
        
        irlan_next_client_state(self, IRLAN_IDLE);
        irlan_next_provider_state(self, IRLAN_IDLE);

        irlan_register_netdev(self);

        return self;
}
/*
 * Function __irlan_close (self)
 *
 *    This function closes and deallocates the IrLAN client instances. Be 
 *    aware that other functions which calles client_close() must call 
 *    hashbin_remove() first!!!
 */
static void __irlan_close(struct irlan_cb *self)
{
        struct sk_buff *skb;

        IRDA_DEBUG(2, __FUNCTION__ "()\n");
        
        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);

        del_timer(&self->watchdog_timer);
        del_timer(&self->client.kick_timer);

        /* Close all open connections and remove TSAPs */
        irlan_close_tsaps(self);
        
        if (self->client.iriap) 
                iriap_close(self->client.iriap);

        /* Remove frames queued on the control channel */
        while ((skb = skb_dequeue(&self->client.txq)))
                dev_kfree_skb(skb);
        
        unregister_netdev(&self->dev);
        
        self->magic = 0;
        kfree(self);
}

/*
 * Function irlan_connect_indication (instance, sap, qos, max_sdu_size, skb)
 *
 *    Here we receive the connect indication for the data channel
 *
 */
void irlan_connect_indication(void *instance, void *sap, struct qos_info *qos,
                              __u32 max_sdu_size, __u8 max_header_size, 
                              struct sk_buff *skb)
{
        struct irlan_cb *self;
        struct tsap_cb *tsap;

        IRDA_DEBUG(2, __FUNCTION__ "()\n");
        
        self = (struct irlan_cb *) instance;
        tsap = (struct tsap_cb *) sap;
        
        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);
        ASSERT(tsap == self->tsap_data,return;);

        self->max_sdu_size = max_sdu_size;
        self->max_header_size = max_header_size;

        IRDA_DEBUG(0, "IrLAN, We are now connected!\n");

        del_timer(&self->watchdog_timer);

        irlan_do_provider_event(self, IRLAN_DATA_CONNECT_INDICATION, skb);
        irlan_do_client_event(self, IRLAN_DATA_CONNECT_INDICATION, skb);

        if (self->provider.access_type == ACCESS_PEER) {
                /* 
                 * Data channel is open, so we are now allowed to
                 * configure the remote filter 
                 */
                irlan_get_unicast_addr(self);
                irlan_open_unicast_addr(self);
        }
        /* Ready to transfer Ethernet frames (at last) */
        self->dev.tbusy = 0;
        self->disconnect_reason = 0; /* Clear reason */
}

void irlan_connect_confirm(void *instance, void *sap, struct qos_info *qos, 
                           __u32 max_sdu_size, __u8 max_header_size, 
                           struct sk_buff *skb) 
{
        struct irlan_cb *self;

        self = (struct irlan_cb *) instance;

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);

        self->max_sdu_size = max_sdu_size;
        self->max_header_size = max_header_size;

        /* TODO: we could set the MTU depending on the max_sdu_size */

        IRDA_DEBUG(2, "IrLAN, We are now connected!\n");
        del_timer(&self->watchdog_timer);

        /* 
         * Data channel is open, so we are now allowed to configure the remote
         * filter 
         */
        irlan_get_unicast_addr(self);
        irlan_open_unicast_addr(self);
        
        /* Open broadcast and multicast filter by default */
        irlan_set_broadcast_filter(self, TRUE);
        irlan_set_multicast_filter(self, TRUE);

        /* Ready to transfer Ethernet frames */
        self->dev.tbusy = 0;
        self->dev.start = 1;
        self->disconnect_reason = 0; /* Clear reason */

#ifdef CONFIG_IRLAN_SEND_GRATUITOUS_ARP
        irlan_eth_send_gratuitous_arp(&self->dev);
#endif
}

/*
 * Function irlan_client_disconnect_indication (handle)
 *
 *    Callback function for the IrTTP layer. Indicates a disconnection of
 *    the specified connection (handle)
 */
void irlan_disconnect_indication(void *instance, void *sap, LM_REASON reason, 
                                 struct sk_buff *userdata) 
{
        struct irlan_cb *self;
        struct tsap_cb *tsap;

        IRDA_DEBUG(0, __FUNCTION__ "(), reason=%d\n", reason);
        
        self = (struct irlan_cb *) instance;
        tsap = (struct tsap_cb *) sap;

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);    
        ASSERT(tsap != NULL, return;);
        ASSERT(tsap->magic == TTP_TSAP_MAGIC, return;);
        
        ASSERT(tsap == self->tsap_data, return;);

        IRDA_DEBUG(2, "IrLAN, data channel disconnected by peer!\n");

        /* Save reason, so we know if we should try to reconnect or not */
        self->disconnect_reason = reason;

        switch (reason) {
        case LM_USER_REQUEST: /* User request */
                IRDA_DEBUG(2, __FUNCTION__ "(), user request\n");
                break;
        case LM_LAP_DISCONNECT: /* Unexpected IrLAP disconnect */
                IRDA_DEBUG(2, __FUNCTION__ "(), Unexpected IrLAP disconnect\n");
                break;
        case LM_CONNECT_FAILURE: /* Failed to establish IrLAP connection */
                IRDA_DEBUG(2, __FUNCTION__ "(), IrLAP connect failed\n");
                break;
        case LM_LAP_RESET:  /* IrLAP reset */
                IRDA_DEBUG(2, __FUNCTION__ "(), IrLAP reset\n");
                break;
        case LM_INIT_DISCONNECT:
                IRDA_DEBUG(2, __FUNCTION__ "(), IrLMP connect failed\n");
                break;
        default:
                ERROR(__FUNCTION__ "(), Unknown disconnect reason\n");
                break;
        }       
        irlan_do_client_event(self, IRLAN_LMP_DISCONNECT, NULL);
        irlan_do_provider_event(self, IRLAN_LMP_DISCONNECT, NULL);
}

void irlan_open_data_tsap(struct irlan_cb *self)
{
        struct tsap_cb *tsap;
        notify_t notify;

        IRDA_DEBUG(2, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);

        /* Check if already open */
        if (self->tsap_data)
                return;

        irda_notify_init(&notify);
        
        notify.data_indication       = irlan_eth_receive;
        notify.udata_indication      = irlan_eth_receive;
        notify.connect_indication    = irlan_connect_indication;
        notify.connect_confirm       = irlan_connect_confirm;
        /*notify.flow_indication       = irlan_eth_flow_indication;*/
        notify.disconnect_indication = irlan_disconnect_indication;
        notify.instance              = self;
        strncpy(notify.name, "IrLAN data", NOTIFY_MAX_NAME);

        tsap = irttp_open_tsap(LSAP_ANY, DEFAULT_INITIAL_CREDIT, &notify);
        if (!tsap) {
                IRDA_DEBUG(2, __FUNCTION__ "(), Got no tsap!\n");
                return;
        }
        self->tsap_data = tsap;

        /* 
         *  This is the data TSAP selector which we will pass to the client
         *  when the client ask for it.
         */
        self->stsap_sel_data = self->tsap_data->stsap_sel;
}

void irlan_close_tsaps(struct irlan_cb *self)
{
        IRDA_DEBUG(4, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);

        /* Disconnect and close all open TSAP connections */
        if (self->tsap_data) {
                irttp_disconnect_request(self->tsap_data, NULL, P_NORMAL);
                irttp_close_tsap(self->tsap_data);
                self->tsap_data = NULL;
        }
        if (self->client.tsap_ctrl) {
                irttp_disconnect_request(self->client.tsap_ctrl, NULL, 
                                         P_NORMAL);
                irttp_close_tsap(self->client.tsap_ctrl);
                self->client.tsap_ctrl = NULL;
        }
        if (self->provider.tsap_ctrl) {
                irttp_disconnect_request(self->provider.tsap_ctrl, NULL, 
                                         P_NORMAL);
                irttp_close_tsap(self->provider.tsap_ctrl);
                self->provider.tsap_ctrl = NULL;
        }
}

/*
 * Function irlan_ias_register (self, tsap_sel)
 *
 *    Register with LM-IAS
 *
 */
void irlan_ias_register(struct irlan_cb *self, __u8 tsap_sel)
{
        struct ias_object *obj;
        struct ias_value *new_value;

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);
        
        /* 
         * Check if object has already been registred by a previous provider.
         * If that is the case, we just change the value of the attribute
         */
        if (!irias_find_object("IrLAN")) {
                obj = irias_new_object("IrLAN", IAS_IRLAN_ID);
                irias_add_integer_attrib(obj, "IrDA:TinyTP:LsapSel", tsap_sel);
                irias_insert_object(obj);
        } else {
                new_value = irias_new_integer_value(tsap_sel);
                irias_object_change_attribute("IrLAN", "IrDA:TinyTP:LsapSel",
                                              new_value);
        }
        
        /* Register PnP object only if not registred before */
        if (!irias_find_object("PnP")) {
                obj = irias_new_object("PnP", IAS_PNP_ID);
#if 0
                irias_add_string_attrib(obj, "Name", sysctl_devname);
#else
                irias_add_string_attrib(obj, "Name", "Linux");
#endif
                irias_add_string_attrib(obj, "DeviceID", "HWP19F0");
                irias_add_integer_attrib(obj, "CompCnt", 1);
                if (self->provider.access_type == ACCESS_PEER)
                        irias_add_string_attrib(obj, "Comp#01", "PNP8389");
                else
                        irias_add_string_attrib(obj, "Comp#01", "PNP8294");

                irias_add_string_attrib(obj, "Manufacturer", "Linux-IrDA Project");
                irias_insert_object(obj);
        }
}

/*
 * Function irlan_run_ctrl_tx_queue (self)
 *
 *    Try to send the next command in the control transmit queue
 *
 */
int irlan_run_ctrl_tx_queue(struct irlan_cb *self)
{
        struct sk_buff *skb;

        IRDA_DEBUG(2, __FUNCTION__ "()\n");

        if (irda_lock(&self->client.tx_busy) == FALSE)
                return -EBUSY;

        skb = skb_dequeue(&self->client.txq);
        if (!skb) {
                self->client.tx_busy = FALSE;
                return 0;
        }
        
        /* Check that it's really possible to send commands */
        if ((self->client.tsap_ctrl == NULL) || 
            (self->client.state == IRLAN_IDLE)) 
        {
                self->client.tx_busy = FALSE;
                dev_kfree_skb(skb);
                return -1;
        }
        IRDA_DEBUG(2, __FUNCTION__ "(), sending ...\n");

        return irttp_data_request(self->client.tsap_ctrl, skb);
}

/*
 * Function irlan_ctrl_data_request (self, skb)
 *
 *    This function makes sure that commands on the control channel is being
 *    sent in a command/response fashion
 */
void irlan_ctrl_data_request(struct irlan_cb *self, struct sk_buff *skb)
{
        IRDA_DEBUG(2, __FUNCTION__ "()\n");

        /* Queue command */
        skb_queue_tail(&self->client.txq, skb);

        /* Try to send command */
        irlan_run_ctrl_tx_queue(self);
}

/*
 * Function irlan_get_provider_info (self)
 *
 *    Send Get Provider Information command to peer IrLAN layer
 *
 */
void irlan_get_provider_info(struct irlan_cb *self)
{
        struct sk_buff *skb;
        __u8 *frame;

        IRDA_DEBUG(4, __FUNCTION__ "()\n");
        
        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);

        skb = dev_alloc_skb(64);
        if (!skb)
                return;

        /* Reserve space for TTP, LMP, and LAP header */
        skb_reserve(skb, self->client.max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        frame[0] = CMD_GET_PROVIDER_INFO;
        frame[1] = 0x00;                 /* Zero parameters */
        
        irlan_ctrl_data_request(self, skb);
}

/*
 * Function irlan_open_data_channel (self)
 *
 *    Send an Open Data Command to provider
 *
 */
void irlan_open_data_channel(struct irlan_cb *self) 
{
        struct sk_buff *skb;
        __u8 *frame;
        
        IRDA_DEBUG(4, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);
        
        skb = dev_alloc_skb(64);
        if (!skb)
                return;

        skb_reserve(skb, self->client.max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        /* Build frame */
        frame[0] = CMD_OPEN_DATA_CHANNEL;
        frame[1] = 0x02; /* Two parameters */

        irlan_insert_string_param(skb, "MEDIA", "802.3");
        irlan_insert_string_param(skb, "ACCESS_TYPE", "DIRECT");
        /* irlan_insert_string_param(skb, "MODE", "UNRELIABLE"); */

/*      self->use_udata = TRUE; */

        irlan_ctrl_data_request(self, skb);
}

void irlan_close_data_channel(struct irlan_cb *self) 
{
        struct sk_buff *skb;
        __u8 *frame;
        
        IRDA_DEBUG(4, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);

        /* Check if the TSAP is still there */
        if (self->client.tsap_ctrl == NULL)
                return;

        skb = dev_alloc_skb(64);
        if (!skb)
                return;

        skb_reserve(skb, self->client.max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        /* Build frame */
        frame[0] = CMD_CLOSE_DATA_CHAN;
        frame[1] = 0x01; /* Two parameters */

        irlan_insert_byte_param(skb, "DATA_CHAN", self->dtsap_sel_data);

        irlan_ctrl_data_request(self, skb);
}

/*
 * Function irlan_open_unicast_addr (self)
 *
 *    Make IrLAN provider accept ethernet frames addressed to the unicast 
 *    address.
 *
 */
void irlan_open_unicast_addr(struct irlan_cb *self) 
{
        struct sk_buff *skb;
        __u8 *frame;
        
        IRDA_DEBUG(4, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);    
        
        skb = dev_alloc_skb(128);
        if (!skb)
                return;

        /* Reserve space for TTP, LMP, and LAP header */
        skb_reserve(skb, self->max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        frame[0] = CMD_FILTER_OPERATION;
        frame[1] = 0x03;                 /* Three parameters */
        irlan_insert_byte_param(skb, "DATA_CHAN" , self->dtsap_sel_data);
        irlan_insert_string_param(skb, "FILTER_TYPE", "DIRECTED");
        irlan_insert_string_param(skb, "FILTER_MODE", "FILTER"); 
        
        irlan_ctrl_data_request(self, skb);
}

/*
 * Function irlan_set_broadcast_filter (self, status)
 *
 *    Make IrLAN provider accept ethernet frames addressed to the broadcast
 *    address. Be careful with the use of this one, since there may be a lot
 *    of broadcast traffic out there. We can still function without this
 *    one but then _we_ have to initiate all communication with other
 *    hosts, since ARP request for this host will not be answered.
 */
void irlan_set_broadcast_filter(struct irlan_cb *self, int status) 
{
        struct sk_buff *skb;
        __u8 *frame;
        
        IRDA_DEBUG(2, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);
        
        skb = dev_alloc_skb(128);
        if (!skb)
                return;

        /* Reserve space for TTP, LMP, and LAP header */
        skb_reserve(skb, self->client.max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        frame[0] = CMD_FILTER_OPERATION;
        frame[1] = 0x03;                 /* Three parameters */
        irlan_insert_byte_param(skb, "DATA_CHAN", self->dtsap_sel_data);
        irlan_insert_string_param(skb, "FILTER_TYPE", "BROADCAST");
        if (status)
                irlan_insert_string_param(skb, "FILTER_MODE", "FILTER"); 
        else
                irlan_insert_string_param(skb, "FILTER_MODE", "NONE"); 

        irlan_ctrl_data_request(self, skb);
}

/*
 * Function irlan_set_multicast_filter (self, status)
 *
 *    Make IrLAN provider accept ethernet frames addressed to the multicast
 *    address. 
 *
 */
void irlan_set_multicast_filter(struct irlan_cb *self, int status) 
{
        struct sk_buff *skb;
        __u8 *frame;
        
        IRDA_DEBUG(2, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);

        skb = dev_alloc_skb(128);
        if (!skb)
                return;
        
        /* Reserve space for TTP, LMP, and LAP header */
        skb_reserve(skb, self->client.max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        frame[0] = CMD_FILTER_OPERATION;
        frame[1] = 0x03;                 /* Three parameters */
        irlan_insert_byte_param(skb, "DATA_CHAN", self->dtsap_sel_data);
        irlan_insert_string_param(skb, "FILTER_TYPE", "MULTICAST");
        if (status)
                irlan_insert_string_param(skb, "FILTER_MODE", "ALL"); 
        else
                irlan_insert_string_param(skb, "FILTER_MODE", "NONE"); 

        irlan_ctrl_data_request(self, skb);
}

/*
 * Function irlan_get_unicast_addr (self)
 *
 *    Retrives the unicast address from the IrLAN provider. This address
 *    will be inserted into the devices structure, so the ethernet layer
 *    can construct its packets.
 *
 */
void irlan_get_unicast_addr(struct irlan_cb *self) 
{
        struct sk_buff *skb;
        __u8 *frame;
                
        IRDA_DEBUG(2, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);
        
        skb = dev_alloc_skb(128);
        if (!skb)
                return;

        /* Reserve space for TTP, LMP, and LAP header */
        skb_reserve(skb, self->client.max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        frame[0] = CMD_FILTER_OPERATION;
        frame[1] = 0x03;                 /* Three parameters */
        irlan_insert_byte_param(skb, "DATA_CHAN", self->dtsap_sel_data);
        irlan_insert_string_param(skb, "FILTER_TYPE", "DIRECTED");
        irlan_insert_string_param(skb, "FILTER_OPERATION", "DYNAMIC"); 
        
        irlan_ctrl_data_request(self, skb);
}

/*
 * Function irlan_get_media_char (self)
 *
 *    
 *
 */
void irlan_get_media_char(struct irlan_cb *self) 
{
        struct sk_buff *skb;
        __u8 *frame;
        
        IRDA_DEBUG(4, __FUNCTION__ "()\n");

        ASSERT(self != NULL, return;);
        ASSERT(self->magic == IRLAN_MAGIC, return;);
        
        skb = dev_alloc_skb(64);
        if (!skb)
                return;

        /* Reserve space for TTP, LMP, and LAP header */
        skb_reserve(skb, self->client.max_header_size);
        skb_put(skb, 2);
        
        frame = skb->data;
        
        /* Build frame */
        frame[0] = CMD_GET_MEDIA_CHAR;
        frame[1] = 0x01; /* One parameter */
        
        irlan_insert_string_param(skb, "MEDIA", "802.3");
        
        irlan_ctrl_data_request(self, skb);
}

/*
 * Function insert_byte_param (skb, param, value)
 *
 *    Insert byte parameter into frame
 *
 */
int irlan_insert_byte_param(struct sk_buff *skb, char *param, __u8 value)
{
        return __irlan_insert_param(skb, param, IRLAN_BYTE, value, 0, NULL, 0);
}

int irlan_insert_short_param(struct sk_buff *skb, char *param, __u16 value)
{
        return __irlan_insert_param(skb, param, IRLAN_SHORT, 0, value, NULL, 0);
}

/*
 * Function insert_string (skb, param, value)
 *
 *    Insert string parameter into frame
 *
 */
int irlan_insert_string_param(struct sk_buff *skb, char *param, char *string)
{
        int string_len = strlen(string);

        return __irlan_insert_param(skb, param, IRLAN_ARRAY, 0, 0, string, 
                                    string_len);
}

/*
 * Function insert_array_param(skb, param, value, len_value)
 *
 *    Insert array parameter into frame
 *
 */
int irlan_insert_array_param(struct sk_buff *skb, char *name, __u8 *array,
                             __u16 array_len)
{
        return __irlan_insert_param(skb, name, IRLAN_ARRAY, 0, 0, array, 
                                    array_len);
}

/*
 * Function insert_param (skb, param, value, byte)
 *
 *    Insert parameter at end of buffer, structure of a parameter is:
 *
 *    -----------------------------------------------------------------------
 *    | Name Length[1] | Param Name[1..255] | Val Length[2] | Value[0..1016]|
 *    -----------------------------------------------------------------------
 */
static int __irlan_insert_param(struct sk_buff *skb, char *param, int type, 
                                __u8 value_byte, __u16 value_short, 
                                __u8 *value_array, __u16 value_len)
{
        __u8 *frame;
        __u8 param_len;
        __u16 tmp_le; /* Temporary value in little endian format */
        int n=0;
        
        if (skb == NULL) {
                IRDA_DEBUG(2, __FUNCTION__ "(), Got NULL skb\n");
                return 0;
        }       

        param_len = strlen(param);
        switch (type) {
        case IRLAN_BYTE:
                value_len = 1;
                break;
        case IRLAN_SHORT:
                value_len = 2;
                break;
        case IRLAN_ARRAY:
                ASSERT(value_array != NULL, return 0;);
                ASSERT(value_len > 0, return 0;);
                break;
        default:
                IRDA_DEBUG(2, __FUNCTION__ "(), Unknown parameter type!\n");
                return 0;
                break;
        }
        
        /* Insert at end of sk-buffer */
        frame = skb->tail;

        /* Make space for data */
        if (skb_tailroom(skb) < (param_len+value_len+3)) {
                IRDA_DEBUG(2, __FUNCTION__ "(), No more space at end of skb\n");
                return 0;
        }       
        skb_put(skb, param_len+value_len+3);
        
        /* Insert parameter length */
        frame[n++] = param_len;
        
        /* Insert parameter */
        memcpy(frame+n, param, param_len); n += param_len;
        
        /* Insert value length (2 byte little endian format, LSB first) */
        tmp_le = cpu_to_le16(value_len);
        memcpy(frame+n, &tmp_le, 2); n += 2; /* To avoid alignment problems */

        /* Insert value */
        switch (type) {
        case IRLAN_BYTE:
                frame[n++] = value_byte;
                break;
        case IRLAN_SHORT:
                tmp_le = cpu_to_le16(value_short);
                memcpy(frame+n, &tmp_le, 2); n += 2;
                break;
        case IRLAN_ARRAY:
                memcpy(frame+n, value_array, value_len); n+=value_len;
                break;
        default:
                break;
        }
        ASSERT(n == (param_len+value_len+3), return 0;);

        return param_len+value_len+3;
}

/*
 * Function irlan_extract_param (buf, name, value, len)
 *
 *    Extracts a single parameter name/value pair from buffer and updates
 *    the buffer pointer to point to the next name/value pair. 
 */
int irlan_extract_param(__u8 *buf, char *name, char *value, __u16 *len)
{
        __u8 name_len;
        __u16 val_len;
        int n=0;
        
        IRDA_DEBUG(4, __FUNCTION__ "()\n");
        
        /* get length of parameter name (1 byte) */
        name_len = buf[n++];
        
        if (name_len > 254) {
                IRDA_DEBUG(2, __FUNCTION__ "(), name_len > 254\n");
                return -RSP_INVALID_COMMAND_FORMAT;
        }
        
        /* get parameter name */
        memcpy(name, buf+n, name_len);
        name[name_len] = '\0';
        n+=name_len;
        
        /*  
         *  Get length of parameter value (2 bytes in little endian 
         *  format) 
         */
        memcpy(&val_len, buf+n, 2); /* To avoid alignment problems */
        le16_to_cpus(&val_len); n+=2;
        
        if (val_len > 1016) {
                IRDA_DEBUG(2, __FUNCTION__ "(), parameter length to long\n");
                return -RSP_INVALID_COMMAND_FORMAT;
        }
        *len = val_len;

        /* get parameter value */
        memcpy(value, buf+n, val_len);
        value[val_len] = '\0';
        n+=val_len;
        
        IRDA_DEBUG(4, "Parameter: %s ", name); 
        IRDA_DEBUG(4, "Value: %s\n", value); 

        return n;
}

#ifdef CONFIG_PROC_FS
/*
 * Function irlan_client_proc_read (buf, start, offset, len, unused)
 *
 *    Give some info to the /proc file system
 */
static int irlan_proc_read(char *buf, char **start, off_t offset, int len, 
                           int unused)
{
        struct irlan_cb *self;
        unsigned long flags;
     
        save_flags(flags);
        cli();

        ASSERT(irlan != NULL, return 0;);
        
        len = 0;
        
        len += sprintf(buf+len, "IrLAN instances:\n");
        
        self = (struct irlan_cb *) hashbin_get_first(irlan);
        while (self != NULL) {
                ASSERT(self->magic == IRLAN_MAGIC, return len;);
                
                len += sprintf(buf+len, "ifname: %s,\n",
                               self->ifname);
                len += sprintf(buf+len, "client state: %s, ",
                               irlan_state[ self->client.state]);
                len += sprintf(buf+len, "provider state: %s,\n",
                               irlan_state[ self->provider.state]);
                len += sprintf(buf+len, "saddr: %#08x, ",
                               self->saddr);
                len += sprintf(buf+len, "daddr: %#08x\n",
                               self->daddr);
                len += sprintf(buf+len, "version: %d.%d,\n",
                               self->version[1], self->version[0]);
                len += sprintf(buf+len, "access type: %s\n", 
                               irlan_access[self->client.access_type]);
                len += sprintf(buf+len, "media: %s\n", 
                               irlan_media[self->media]);
                
                len += sprintf(buf+len, "local filter:\n");
                len += sprintf(buf+len, "remote filter: ");
                len += irlan_print_filter(self->client.filter_type, 
                                          buf+len);
                
                len += sprintf(buf+len, "client tx busy: %s\n", 
                               self->client.tx_busy ? "TRUE" : "FALSE");
                
                len += sprintf(buf+len, "dev tx busy: %s\n", 
                               self->dev.tbusy ? "TRUE" : "FALSE");
                
                len += sprintf(buf+len, "\n");

                self = (struct irlan_cb *) hashbin_get_next(irlan);
        } 
        restore_flags(flags);

        return len;
}
#endif

/*
 * Function print_ret_code (code)
 *
 *    Print return code of request to peer IrLAN layer.
 *
 */
void print_ret_code(__u8 code) 
{
        switch(code) {
        case 0:
                printk(KERN_INFO "Success\n");
                break;
        case 1:
                WARNING("IrLAN: Insufficient resources\n");
                break;
        case 2:
                WARNING("IrLAN: Invalid command format\n");
                break;
        case 3:
                WARNING("IrLAN: Command not supported\n");
                break;
        case 4:
                WARNING("IrLAN: Parameter not supported\n");
                break;
        case 5:
                WARNING("IrLAN: Value not supported\n");
                break;
        case 6:
                WARNING("IrLAN: Not open\n");
                break;
        case 7:
                WARNING("IrLAN: Authentication required\n");
                break;
        case 8:
                WARNING("IrLAN: Invalid password\n");
                break;
        case 9:
                WARNING("IrLAN: Protocol error\n");
                break;
        case 255:
                WARNING("IrLAN: Asynchronous status\n");
                break;
        }
}

void irlan_mod_inc_use_count(void)
{
#ifdef MODULE
        MOD_INC_USE_COUNT;
#endif
}

void irlan_mod_dec_use_count(void)
{
#ifdef MODULE
        MOD_DEC_USE_COUNT;
#endif
}

#ifdef MODULE

MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
MODULE_DESCRIPTION("The Linux IrDA LAN protocol"); 

MODULE_PARM(eth, "i");
MODULE_PARM(access, "i");
MODULE_PARM(timeout, "i");

/*
 * Function init_module (void)
 *
 *    Initialize the IrLAN module, this function is called by the
 *    modprobe(1) program.
 */
int init_module(void) 
{
        return irlan_init();
}

/*
 * Function cleanup_module (void)
 *
 *    Remove the IrLAN module, this function is called by the rmmod(1)
 *    program
 */
void cleanup_module(void) 
{
        /* Free some memory */
        irlan_cleanup();
}

#endif /* MODULE */

---