rose_route.c

linux 内核源代码

	while (rose_node != NULL) {
		if ((rose_node->mask == 10) &&
		    (rosecmpm(address, &rose_node->address, 10) == 0) &&
		    rose_node->loopback)
			break;
		rose_node = rose_node->next;
	}

	if (rose_node == NULL)
		goto out;

	rose_remove_node(rose_node);

	rose_loopback_neigh->count--;

out:
	spin_unlock_bh(&rose_node_list_lock);
}

/*
 *	A device has been removed. Remove its routes and neighbours.
 */
void rose_rt_device_down(struct net_device *dev)
{
	struct rose_neigh *s, *rose_neigh;
	struct rose_node  *t, *rose_node;
	int i;

	spin_lock_bh(&rose_node_list_lock);
	spin_lock_bh(&rose_neigh_list_lock);
	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		s          = rose_neigh;
		rose_neigh = rose_neigh->next;

		if (s->dev != dev)
			continue;

		rose_node = rose_node_list;

		while (rose_node != NULL) {
			t         = rose_node;
			rose_node = rose_node->next;

			for (i = 0; i < t->count; i++) {
				if (t->neighbour[i] != s)
					continue;

				t->count--;

				switch (i) {
				case 0:
					t->neighbour[0] = t->neighbour[1];
				case 1:
					t->neighbour[1] = t->neighbour[2];
				case 2:
					break;
				}
			}

			if (t->count <= 0)
				rose_remove_node(t);
		}

		rose_remove_neigh(s);
	}
	spin_unlock_bh(&rose_neigh_list_lock);
	spin_unlock_bh(&rose_node_list_lock);
}

#if 0 /* Currently unused */
/*
 *	A device has been removed. Remove its links.
 */
void rose_route_device_down(struct net_device *dev)
{
	struct rose_route *s, *rose_route;

	spin_lock_bh(&rose_route_list_lock);
	rose_route = rose_route_list;
	while (rose_route != NULL) {
		s          = rose_route;
		rose_route = rose_route->next;

		if (s->neigh1->dev == dev || s->neigh2->dev == dev)
			rose_remove_route(s);
	}
	spin_unlock_bh(&rose_route_list_lock);
}
#endif

/*
 *	Clear all nodes and neighbours out, except for neighbours with
 *	active connections going through them.
 *  Do not clear loopback neighbour and nodes.
 */
static int rose_clear_routes(void)
{
	struct rose_neigh *s, *rose_neigh;
	struct rose_node  *t, *rose_node;

	spin_lock_bh(&rose_node_list_lock);
	spin_lock_bh(&rose_neigh_list_lock);

	rose_neigh = rose_neigh_list;
	rose_node  = rose_node_list;

	while (rose_node != NULL) {
		t         = rose_node;
		rose_node = rose_node->next;
		if (!t->loopback)
			rose_remove_node(t);
	}

	while (rose_neigh != NULL) {
		s          = rose_neigh;
		rose_neigh = rose_neigh->next;

		if (s->use == 0 && !s->loopback) {
			s->count = 0;
			rose_remove_neigh(s);
		}
	}

	spin_unlock_bh(&rose_neigh_list_lock);
	spin_unlock_bh(&rose_node_list_lock);

	return 0;
}

/*
 *	Check that the device given is a valid AX.25 interface that is "up".
 */
static struct net_device *rose_ax25_dev_get(char *devname)
{
	struct net_device *dev;

	if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
		return NULL;

	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
		return dev;

	dev_put(dev);
	return NULL;
}

/*
 *	Find the first active ROSE device, usually "rose0".
 */
struct net_device *rose_dev_first(void)
{
	struct net_device *dev, *first = NULL;

	read_lock(&dev_base_lock);
	for_each_netdev(&init_net, dev) {
		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
				first = dev;
	}
	read_unlock(&dev_base_lock);

	return first;
}

/*
 *	Find the ROSE device for the given address.
 */
struct net_device *rose_dev_get(rose_address *addr)
{
	struct net_device *dev;

	read_lock(&dev_base_lock);
	for_each_netdev(&init_net, dev) {
		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0) {
			dev_hold(dev);
			goto out;
		}
	}
	dev = NULL;
out:
	read_unlock(&dev_base_lock);
	return dev;
}

static int rose_dev_exists(rose_address *addr)
{
	struct net_device *dev;

	read_lock(&dev_base_lock);
	for_each_netdev(&init_net, dev) {
		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0)
			goto out;
	}
	dev = NULL;
out:
	read_unlock(&dev_base_lock);
	return dev != NULL;
}




struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
{
	struct rose_route *rose_route;

	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
			return rose_route;

	return NULL;
}

/*
 *	Find a neighbour given a ROSE address.
 */
struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
	unsigned char *diagnostic)
{
	struct rose_neigh *res = NULL;
	struct rose_node *node;
	int failed = 0;
	int i;

	spin_lock_bh(&rose_node_list_lock);
	for (node = rose_node_list; node != NULL; node = node->next) {
		if (rosecmpm(addr, &node->address, node->mask) == 0) {
			for (i = 0; i < node->count; i++) {
				if (!rose_ftimer_running(node->neighbour[i])) {
					res = node->neighbour[i];
					goto out;
				} else
					failed = 1;
			}
			break;
		}
	}

	if (failed) {
		*cause      = ROSE_OUT_OF_ORDER;
		*diagnostic = 0;
	} else {
		*cause      = ROSE_NOT_OBTAINABLE;
		*diagnostic = 0;
	}

out:
	spin_unlock_bh(&rose_node_list_lock);

	return res;
}

/*
 *	Handle the ioctls that control the routing functions.
 */
int rose_rt_ioctl(unsigned int cmd, void __user *arg)
{
	struct rose_route_struct rose_route;
	struct net_device *dev;
	int err;

	switch (cmd) {
	case SIOCADDRT:
		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
			return -EFAULT;
		if ((dev = rose_ax25_dev_get(rose_route.device)) == NULL)
			return -EINVAL;
		if (rose_dev_exists(&rose_route.address)) { /* Can't add routes to ourself */
			dev_put(dev);
			return -EINVAL;
		}
		if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
			return -EINVAL;
		if (rose_route.ndigis > AX25_MAX_DIGIS)
			return -EINVAL;
		err = rose_add_node(&rose_route, dev);
		dev_put(dev);
		return err;

	case SIOCDELRT:
		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
			return -EFAULT;
		if ((dev = rose_ax25_dev_get(rose_route.device)) == NULL)
			return -EINVAL;
		err = rose_del_node(&rose_route, dev);
		dev_put(dev);
		return err;

	case SIOCRSCLRRT:
		return rose_clear_routes();

	default:
		return -EINVAL;
	}

	return 0;
}

static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
{
	struct rose_route *rose_route, *s;

	rose_neigh->restarted = 0;

	rose_stop_t0timer(rose_neigh);
	rose_start_ftimer(rose_neigh);

	skb_queue_purge(&rose_neigh->queue);

	spin_lock_bh(&rose_route_list_lock);

	rose_route = rose_route_list;

	while (rose_route != NULL) {
		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
			s = rose_route->next;
			rose_remove_route(rose_route);
			rose_route = s;
			continue;
		}

		if (rose_route->neigh1 == rose_neigh) {
			rose_route->neigh1->use--;
			rose_route->neigh1 = NULL;
			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
		}

		if (rose_route->neigh2 == rose_neigh) {
			rose_route->neigh2->use--;
			rose_route->neigh2 = NULL;
			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
		}

		rose_route = rose_route->next;
	}
	spin_unlock_bh(&rose_route_list_lock);
}

/*
 * 	A level 2 link has timed out, therefore it appears to be a poor link,
 *	then don't use that neighbour until it is reset. Blow away all through
 *	routes and connections using this route.
 */
void rose_link_failed(ax25_cb *ax25, int reason)
{
	struct rose_neigh *rose_neigh;

	spin_lock_bh(&rose_neigh_list_lock);
	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		if (rose_neigh->ax25 == ax25)
			break;
		rose_neigh = rose_neigh->next;
	}

	if (rose_neigh != NULL) {
		rose_neigh->ax25 = NULL;

		rose_del_route_by_neigh(rose_neigh);
		rose_kill_by_neigh(rose_neigh);
	}
	spin_unlock_bh(&rose_neigh_list_lock);
}

/*
 * 	A device has been "downed" remove its link status. Blow away all
 *	through routes and connections that use this device.
 */
void rose_link_device_down(struct net_device *dev)
{
	struct rose_neigh *rose_neigh;

	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
		if (rose_neigh->dev == dev) {
			rose_del_route_by_neigh(rose_neigh);
			rose_kill_by_neigh(rose_neigh);
		}
	}
}

/*
 *	Route a frame to an appropriate AX.25 connection.
 */
int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
{
	struct rose_neigh *rose_neigh, *new_neigh;
	struct rose_route *rose_route;
	struct rose_facilities_struct facilities;
	rose_address *src_addr, *dest_addr;
	struct sock *sk;
	unsigned short frametype;
	unsigned int lci, new_lci;
	unsigned char cause, diagnostic;
	struct net_device *dev;
	int len, res = 0;
	char buf[11];

#if 0
	if (call_in_firewall(PF_ROSE, skb->dev, skb->data, NULL, &skb) != FW_ACCEPT)
		return res;
#endif

	frametype = skb->data[2];
	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
	src_addr  = (rose_address *)(skb->data + 9);
	dest_addr = (rose_address *)(skb->data + 4);

	spin_lock_bh(&rose_node_list_lock);
	spin_lock_bh(&rose_neigh_list_lock);
	spin_lock_bh(&rose_route_list_lock);

	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
		    ax25->ax25_dev->dev == rose_neigh->dev)
			break;
		rose_neigh = rose_neigh->next;
	}

	if (rose_neigh == NULL) {
		printk("rose_route : unknown neighbour or device %s\n",
		       ax2asc(buf, &ax25->dest_addr));
		goto out;
	}

	/*
	 *	Obviously the link is working, halt the ftimer.
	 */
	rose_stop_ftimer(rose_neigh);

	/*
	 *	LCI of zero is always for us, and its always a restart
	 * 	frame.
	 */
	if (lci == 0) {
		rose_link_rx_restart(skb, rose_neigh, frametype);
		goto out;
	}

	/*
	 *	Find an existing socket.
	 */
	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
		if (frametype == ROSE_CALL_REQUEST) {