dn_dev.c

linux 内核源代码

	ptr += 7;
	i2 = ptr++;

	n = dn_neigh_elist(dev, ptr, n);

	*i2 = 7 * n;
	*i1 = 8 + *i2;

	skb_trim(skb, (27 + *i2));

	pktlen = (__le16 *)skb_push(skb, 2);
	*pktlen = dn_htons(skb->len - 2);

	skb_reset_network_header(skb);

	if (dn_am_i_a_router(dn, dn_db, ifa)) {
		struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
		if (skb2) {
			dn_rt_finish_output(skb2, dn_rt_all_end_mcast, src);
		}
	}

	dn_rt_finish_output(skb, dn_rt_all_rt_mcast, src);
}

static void dn_send_brd_hello(struct net_device *dev, struct dn_ifaddr *ifa)
{
	struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;

	if (dn_db->parms.forwarding == 0)
		dn_send_endnode_hello(dev, ifa);
	else
		dn_send_router_hello(dev, ifa);
}

static void dn_send_ptp_hello(struct net_device *dev, struct dn_ifaddr *ifa)
{
	int tdlen = 16;
	int size = dev->hard_header_len + 2 + 4 + tdlen;
	struct sk_buff *skb = dn_alloc_skb(NULL, size, GFP_ATOMIC);
	int i;
	unsigned char *ptr;
	char src[ETH_ALEN];

	if (skb == NULL)
		return ;

	skb->dev = dev;
	skb_push(skb, dev->hard_header_len);
	ptr = skb_put(skb, 2 + 4 + tdlen);

	*ptr++ = DN_RT_PKT_HELO;
	*((__le16 *)ptr) = ifa->ifa_local;
	ptr += 2;
	*ptr++ = tdlen;

	for(i = 0; i < tdlen; i++)
		*ptr++ = 0252;

	dn_dn2eth(src, ifa->ifa_local);
	dn_rt_finish_output(skb, dn_rt_all_rt_mcast, src);
}

static int dn_eth_up(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db->parms.forwarding == 0)
		dev_mc_add(dev, dn_rt_all_end_mcast, ETH_ALEN, 0);
	else
		dev_mc_add(dev, dn_rt_all_rt_mcast, ETH_ALEN, 0);

	dn_db->use_long = 1;

	return 0;
}

static void dn_eth_down(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db->parms.forwarding == 0)
		dev_mc_delete(dev, dn_rt_all_end_mcast, ETH_ALEN, 0);
	else
		dev_mc_delete(dev, dn_rt_all_rt_mcast, ETH_ALEN, 0);
}

static void dn_dev_set_timer(struct net_device *dev);

static void dn_dev_timer_func(unsigned long arg)
{
	struct net_device *dev = (struct net_device *)arg;
	struct dn_dev *dn_db = dev->dn_ptr;
	struct dn_ifaddr *ifa;

	if (dn_db->t3 <= dn_db->parms.t2) {
		if (dn_db->parms.timer3) {
			for(ifa = dn_db->ifa_list; ifa; ifa = ifa->ifa_next) {
				if (!(ifa->ifa_flags & IFA_F_SECONDARY))
					dn_db->parms.timer3(dev, ifa);
			}
		}
		dn_db->t3 = dn_db->parms.t3;
	} else {
		dn_db->t3 -= dn_db->parms.t2;
	}

	dn_dev_set_timer(dev);
}

static void dn_dev_set_timer(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db->parms.t2 > dn_db->parms.t3)
		dn_db->parms.t2 = dn_db->parms.t3;

	dn_db->timer.data = (unsigned long)dev;
	dn_db->timer.function = dn_dev_timer_func;
	dn_db->timer.expires = jiffies + (dn_db->parms.t2 * HZ);

	add_timer(&dn_db->timer);
}

struct dn_dev *dn_dev_create(struct net_device *dev, int *err)
{
	int i;
	struct dn_dev_parms *p = dn_dev_list;
	struct dn_dev *dn_db;

	for(i = 0; i < DN_DEV_LIST_SIZE; i++, p++) {
		if (p->type == dev->type)
			break;
	}

	*err = -ENODEV;
	if (i == DN_DEV_LIST_SIZE)
		return NULL;

	*err = -ENOBUFS;
	if ((dn_db = kzalloc(sizeof(struct dn_dev), GFP_ATOMIC)) == NULL)
		return NULL;

	memcpy(&dn_db->parms, p, sizeof(struct dn_dev_parms));
	smp_wmb();
	dev->dn_ptr = dn_db;
	dn_db->dev = dev;
	init_timer(&dn_db->timer);

	dn_db->uptime = jiffies;

	dn_db->neigh_parms = neigh_parms_alloc(dev, &dn_neigh_table);
	if (!dn_db->neigh_parms) {
		dev->dn_ptr = NULL;
		kfree(dn_db);
		return NULL;
	}

	if (dn_db->parms.up) {
		if (dn_db->parms.up(dev) < 0) {
			neigh_parms_release(&dn_neigh_table, dn_db->neigh_parms);
			dev->dn_ptr = NULL;
			kfree(dn_db);
			return NULL;
		}
	}

	dn_dev_sysctl_register(dev, &dn_db->parms);

	dn_dev_set_timer(dev);

	*err = 0;
	return dn_db;
}


/*
 * This processes a device up event. We only start up
 * the loopback device & ethernet devices with correct
 * MAC addreses automatically. Others must be started
 * specifically.
 *
 * FIXME: How should we configure the loopback address ? If we could dispense
 * with using decnet_address here and for autobind, it will be one less thing
 * for users to worry about setting up.
 */

void dn_dev_up(struct net_device *dev)
{
	struct dn_ifaddr *ifa;
	__le16 addr = decnet_address;
	int maybe_default = 0;
	struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;

	if ((dev->type != ARPHRD_ETHER) && (dev->type != ARPHRD_LOOPBACK))
		return;

	/*
	 * Need to ensure that loopback device has a dn_db attached to it
	 * to allow creation of neighbours against it, even though it might
	 * not have a local address of its own. Might as well do the same for
	 * all autoconfigured interfaces.
	 */
	if (dn_db == NULL) {
		int err;
		dn_db = dn_dev_create(dev, &err);
		if (dn_db == NULL)
			return;
	}

	if (dev->type == ARPHRD_ETHER) {
		if (memcmp(dev->dev_addr, dn_hiord, 4) != 0)
			return;
		addr = dn_eth2dn(dev->dev_addr);
		maybe_default = 1;
	}

	if (addr == 0)
		return;

	if ((ifa = dn_dev_alloc_ifa()) == NULL)
		return;

	ifa->ifa_local = ifa->ifa_address = addr;
	ifa->ifa_flags = 0;
	ifa->ifa_scope = RT_SCOPE_UNIVERSE;
	strcpy(ifa->ifa_label, dev->name);

	dn_dev_set_ifa(dev, ifa);

	/*
	 * Automagically set the default device to the first automatically
	 * configured ethernet card in the system.
	 */
	if (maybe_default) {
		dev_hold(dev);
		if (dn_dev_set_default(dev, 0))
			dev_put(dev);
	}
}

static void dn_dev_delete(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db == NULL)
		return;

	del_timer_sync(&dn_db->timer);
	dn_dev_sysctl_unregister(&dn_db->parms);
	dn_dev_check_default(dev);
	neigh_ifdown(&dn_neigh_table, dev);

	if (dn_db->parms.down)
		dn_db->parms.down(dev);

	dev->dn_ptr = NULL;

	neigh_parms_release(&dn_neigh_table, dn_db->neigh_parms);
	neigh_ifdown(&dn_neigh_table, dev);

	if (dn_db->router)
		neigh_release(dn_db->router);
	if (dn_db->peer)
		neigh_release(dn_db->peer);

	kfree(dn_db);
}

void dn_dev_down(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;
	struct dn_ifaddr *ifa;

	if (dn_db == NULL)
		return;

	while((ifa = dn_db->ifa_list) != NULL) {
		dn_dev_del_ifa(dn_db, &dn_db->ifa_list, 0);
		dn_dev_free_ifa(ifa);
	}

	dn_dev_delete(dev);
}

void dn_dev_init_pkt(struct sk_buff *skb)
{
	return;
}

void dn_dev_veri_pkt(struct sk_buff *skb)
{
	return;
}

void dn_dev_hello(struct sk_buff *skb)
{
	return;
}

void dn_dev_devices_off(void)
{
	struct net_device *dev;

	rtnl_lock();
	for_each_netdev(&init_net, dev)
		dn_dev_down(dev);
	rtnl_unlock();

}

void dn_dev_devices_on(void)
{
	struct net_device *dev;

	rtnl_lock();
	for_each_netdev(&init_net, dev) {
		if (dev->flags & IFF_UP)
			dn_dev_up(dev);
	}
	rtnl_unlock();
}

int register_dnaddr_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_register(&dnaddr_chain, nb);
}

int unregister_dnaddr_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_unregister(&dnaddr_chain, nb);
}

#ifdef CONFIG_PROC_FS
static inline int is_dn_dev(struct net_device *dev)
{
	return dev->dn_ptr != NULL;
}

static void *dn_dev_seq_start(struct seq_file *seq, loff_t *pos)
{
	int i;
	struct net_device *dev;

	read_lock(&dev_base_lock);

	if (*pos == 0)
		return SEQ_START_TOKEN;

	i = 1;
	for_each_netdev(&init_net, dev) {
		if (!is_dn_dev(dev))
			continue;

		if (i++ == *pos)
			return dev;
	}

	return NULL;
}

static void *dn_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	struct net_device *dev;

	++*pos;

	dev = (struct net_device *)v;
	if (v == SEQ_START_TOKEN)
		dev = net_device_entry(&init_net.dev_base_head);

	for_each_netdev_continue(&init_net, dev) {
		if (!is_dn_dev(dev))
			continue;

		return dev;
	}

	return NULL;
}

static void dn_dev_seq_stop(struct seq_file *seq, void *v)
{
	read_unlock(&dev_base_lock);
}

static char *dn_type2asc(char type)
{
	switch(type) {
		case DN_DEV_BCAST:
			return "B";
		case DN_DEV_UCAST:
			return "U";
		case DN_DEV_MPOINT:
			return "M";
	}

	return "?";
}

static int dn_dev_seq_show(struct seq_file *seq, void *v)
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "Name     Flags T1   Timer1 T3   Timer3 BlkSize Pri State DevType    Router Peer\n");
	else {
		struct net_device *dev = v;
		char peer_buf[DN_ASCBUF_LEN];
		char router_buf[DN_ASCBUF_LEN];
		struct dn_dev *dn_db = dev->dn_ptr;

		seq_printf(seq, "%-8s %1s     %04u %04u   %04lu %04lu"
				"   %04hu    %03d %02x    %-10s %-7s %-7s\n",
				dev->name ? dev->name : "???",
				dn_type2asc(dn_db->parms.mode),
				0, 0,
				dn_db->t3, dn_db->parms.t3,
				mtu2blksize(dev),
				dn_db->parms.priority,
				dn_db->parms.state, dn_db->parms.name,
				dn_db->router ? dn_addr2asc(dn_ntohs(*(__le16 *)dn_db->router->primary_key), router_buf) : "",
				dn_db->peer ? dn_addr2asc(dn_ntohs(*(__le16 *)dn_db->peer->primary_key), peer_buf) : "");
	}
	return 0;
}

static const struct seq_operations dn_dev_seq_ops = {
	.start	= dn_dev_seq_start,
	.next	= dn_dev_seq_next,
	.stop	= dn_dev_seq_stop,
	.show	= dn_dev_seq_show,
};

static int dn_dev_seq_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &dn_dev_seq_ops);
}

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

#endif /* CONFIG_PROC_FS */

static int addr[2];
module_param_array(addr, int, NULL, 0444);
MODULE_PARM_DESC(addr, "The DECnet address of this machine: area,node");

void __init dn_dev_init(void)
{
	if (addr[0] > 63 || addr[0] < 0) {
		printk(KERN_ERR "DECnet: Area must be between 0 and 63");
		return;
	}

	if (addr[1] > 1023 || addr[1] < 0) {
		printk(KERN_ERR "DECnet: Node must be between 0 and 1023");
		return;
	}

	decnet_address = dn_htons((addr[0] << 10) | addr[1]);

	dn_dev_devices_on();

	rtnl_register(PF_DECnet, RTM_NEWADDR, dn_nl_newaddr, NULL);
	rtnl_register(PF_DECnet, RTM_DELADDR, dn_nl_deladdr, NULL);
	rtnl_register(PF_DECnet, RTM_GETADDR, NULL, dn_nl_dump_ifaddr);

	proc_net_fops_create(&init_net, "decnet_dev", S_IRUGO, &dn_dev_seq_fops);

#ifdef CONFIG_SYSCTL
	{
		int i;
		for(i = 0; i < DN_DEV_LIST_SIZE; i++)
			dn_dev_sysctl_register(NULL, &dn_dev_list[i]);
	}
#endif /* CONFIG_SYSCTL */
}

void __exit dn_dev_cleanup(void)
{
#ifdef CONFIG_SYSCTL
	{
		int i;
		for(i = 0; i < DN_DEV_LIST_SIZE; i++)
			dn_dev_sysctl_unregister(&dn_dev_list[i]);
	}
#endif /* CONFIG_SYSCTL */

	proc_net_remove(&init_net, "decnet_dev");

	dn_dev_devices_off();
}