irlan_common.c

linux 内核源代码

/*********************************************************************
 *
 * Filename:      irlan_common.c
 * Version:       0.9
 * Description:   IrDA LAN Access Protocol Implementation
 * Status:        Experimental.
 * Author:        Dag Brattli <[e-mail]>
 * Created at:    Sun Aug 31 20:14:37 1997
 * Modified at:   Sun Dec 26 21:53:10 1999
 * Modified by:   Dag Brattli <[e-mail]>
 *
 *     Copyright (c) 1997, 1999 Dag Brattli <[e-mail]>,
 *     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/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/seq_file.h>
#include <linux/random.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/moduleparam.h>
#include <linux/bitops.h>

#include <asm/system.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
 */
static LIST_HEAD(irlans);

static void *ckey;
static void *skey;

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

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

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

extern struct proc_dir_entry *proc_irda;

static int irlan_seq_open(struct inode *inode, struct file *file);

static const struct file_operations irlan_fops = {
	.owner	 = THIS_MODULE,
	.open    = irlan_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
	.release = seq_release,
};

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

static struct irlan_cb *irlan_open(__u32 saddr, __u32 daddr);
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);
static void irlan_open_unicast_addr(struct irlan_cb *self);
static void irlan_get_unicast_addr(struct irlan_cb *self);
void irlan_close_tsaps(struct irlan_cb *self);

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

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

#ifdef CONFIG_PROC_FS
	{ struct proc_dir_entry *proc;
	proc = create_proc_entry("irlan", 0, proc_irda);
	if (!proc) {
		printk(KERN_ERR "irlan_init: can't create /proc entry!\n");
		return -ENODEV;
	}

	proc->proc_fops = &irlan_fops;
	}
#endif /* CONFIG_PROC_FS */

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__ );
	hints = irlmp_service_to_hint(S_LAN);

	/* Register with IrLMP as a client */
	ckey = irlmp_register_client(hints, &irlan_client_discovery_indication,
				     NULL, NULL);
	if (!ckey)
		goto err_ckey;

	/* Register with IrLMP as a service */
	skey = irlmp_register_service(hints);
	if (!skey)
		goto err_skey;

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

	/* 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;

err_open:
	irlmp_unregister_service(skey);
err_skey:
	irlmp_unregister_client(ckey);
err_ckey:
#ifdef CONFIG_PROC_FS
	remove_proc_entry("irlan", proc_irda);
#endif /* CONFIG_PROC_FS */

	return -ENOMEM;
}

static void __exit irlan_cleanup(void)
{
	struct irlan_cb *self, *next;

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

	irlmp_unregister_client(ckey);
	irlmp_unregister_service(skey);

#ifdef CONFIG_PROC_FS
	remove_proc_entry("irlan", proc_irda);
#endif /* CONFIG_PROC_FS */

	/* Cleanup any leftover network devices */
	rtnl_lock();
	list_for_each_entry_safe(self, next, &irlans, dev_list) {
		__irlan_close(self);
	}
	rtnl_unlock();
}

/*
 * 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
 */
static struct irlan_cb *irlan_open(__u32 saddr, __u32 daddr)
{
	struct net_device *dev;
	struct irlan_cb *self;

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

	/* Create network device with irlan */
	dev = alloc_irlandev(eth ? "eth%d" : "irlan%d");
	if (!dev)
		return NULL;

	self = dev->priv;
	self->dev = dev;

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

	/* Provider access can only be PEER, DIRECT, or HOSTED */
	self->provider.access_type = access;
	if (access == ACCESS_DIRECT) {
		/*
		 * Since we are emulating an IrLAN sever we will have to
		 * give ourself an ethernet address!
		 */
		dev->dev_addr[0] = 0x40;
		dev->dev_addr[1] = 0x00;
		dev->dev_addr[2] = 0x00;
		dev->dev_addr[3] = 0x00;
		get_random_bytes(dev->dev_addr+4, 1);
		get_random_bytes(dev->dev_addr+5, 1);
	}

	self->media = MEDIA_802_3;
	self->disconnect_reason = LM_USER_REQUEST;
	init_timer(&self->watchdog_timer);
	init_timer(&self->client.kick_timer);
	init_waitqueue_head(&self->open_wait);

	skb_queue_head_init(&self->client.txq);

	irlan_next_client_state(self, IRLAN_IDLE);
	irlan_next_provider_state(self, IRLAN_IDLE);

	if (register_netdev(dev)) {
		IRDA_DEBUG(2, "%s(), register_netdev() failed!\n",
			   __FUNCTION__ );
		self = NULL;
		free_netdev(dev);
	} else {
		rtnl_lock();
		list_add_rcu(&self->dev_list, &irlans);
		rtnl_unlock();
	}

	return self;
}
/*
 * Function __irlan_close (self)
 *
 *    This function closes and deallocates the IrLAN client instances. Be
 *    aware that other functions which calls client_close() must
 *    remove self from irlans list first.
 */
static void __irlan_close(struct irlan_cb *self)
{
	IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );

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

	del_timer_sync(&self->watchdog_timer);
	del_timer_sync(&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 */
	skb_queue_purge(&self->client.txq);

	/* Unregister and free self via destructor */
	unregister_netdevice(self->dev);
}

/* Find any instance of irlan, used for client discovery wakeup */
struct irlan_cb *irlan_get_any(void)
{
	struct irlan_cb *self;

	list_for_each_entry_rcu(self, &irlans, dev_list) {
		return self;
	}
	return NULL;
}

/*
 * Function irlan_connect_indication (instance, sap, qos, max_sdu_size, skb)
 *
 *    Here we receive the connect indication for the data channel
 *
 */
static 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, "%s()\n", __FUNCTION__ );

	self = (struct irlan_cb *) instance;
	tsap = (struct tsap_cb *) sap;

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

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

	IRDA_DEBUG(0, "%s: We are now connected!\n", __FUNCTION__);

	del_timer(&self->watchdog_timer);

	/* If you want to pass the skb to *both* state machines, you will
	 * need to skb_clone() it, so that you don't free it twice.
	 * As the state machines don't need it, git rid of it here...
	 * Jean II */
	if (skb)
		dev_kfree_skb(skb);

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

	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) */
	netif_start_queue(self->dev); /* Clear reason */
}

static 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;

	IRDA_ASSERT(self != NULL, return;);
	IRDA_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(0, "%s: We are now connected!\n", __FUNCTION__);
	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 */
	netif_start_queue(self->dev);
	self->disconnect_reason = 0; /* Clear reason */
#ifdef CONFIG_IRLAN_SEND_GRATUITOUS_ARP
	irlan_eth_send_gratuitous_arp(&self->dev);
#endif
	wake_up_interruptible(&self->open_wait);
}

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