Example #1
0
static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb)
{
	__be32 saddr = 0;
	u8 dst_ha[MAX_ADDR_LEN], *dst_hw = NULL;
	struct net_device *dev = neigh->dev;
	__be32 target = *(__be32 *)neigh->primary_key;
	int probes = atomic_read(&neigh->probes);
	struct in_device *in_dev;

	rcu_read_lock();
	in_dev = __in_dev_get_rcu(dev);
	if (!in_dev) {
		rcu_read_unlock();
		return;
	}
	switch (IN_DEV_ARP_ANNOUNCE(in_dev)) {
	default:
	case 0:		/* By default announce any local IP */
		if (skb && inet_addr_type(dev_net(dev),
					  ip_hdr(skb)->saddr) == RTN_LOCAL)
			saddr = ip_hdr(skb)->saddr;
		break;
	case 1:		/* Restrict announcements of saddr in same subnet */
		if (!skb)
			break;
		saddr = ip_hdr(skb)->saddr;
		if (inet_addr_type(dev_net(dev), saddr) == RTN_LOCAL) {
			/* saddr should be known to target */
			if (inet_addr_onlink(in_dev, target, saddr))
				break;
		}
		saddr = 0;
		break;
	case 2:		/* Avoid secondary IPs, get a primary/preferred one */
		break;
	}
	rcu_read_unlock();

	if (!saddr)
		saddr = inet_select_addr(dev, target, RT_SCOPE_LINK);

	probes -= neigh->parms->ucast_probes;
	if (probes < 0) {
		if (!(neigh->nud_state & NUD_VALID))
			pr_debug("trying to ucast probe in NUD_INVALID\n");
		neigh_ha_snapshot(dst_ha, neigh, dev);
		dst_hw = dst_ha;
	} else {
		probes -= neigh->parms->app_probes;
		if (probes < 0) {
#ifdef CONFIG_ARPD
			neigh_app_ns(neigh);
#endif
			return;
		}
	}

	arp_send(ARPOP_REQUEST, ETH_P_ARP, target, dev, saddr,
		 dst_hw, dev->dev_addr, NULL);
}
Example #2
0
int arp_find(unsigned char *haddr, struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
	__be32 paddr;
	struct neighbour *n;

	if (!skb_dst(skb)) {
		printk(KERN_DEBUG "arp_find is called with dst==NULL\n");
		kfree_skb(skb);
		return 1;
	}

	paddr = skb_rtable(skb)->rt_gateway;

	if (arp_set_predefined(inet_addr_type(dev_net(dev), paddr), haddr,
			       paddr, dev))
		return 0;

	n = __neigh_lookup(&arp_tbl, &paddr, dev, 1);

	if (n) {
		n->used = jiffies;
		if (n->nud_state & NUD_VALID || neigh_event_send(n, skb) == 0) {
			neigh_ha_snapshot(haddr, n, dev);
			neigh_release(n);
			return 0;
		}
		neigh_release(n);
	} else
		kfree_skb(skb);
	return 1;
}
Example #3
0
static int
__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res,
	       struct net_device *dev, struct netdev_queue *txq,
	       struct neighbour *mn)
{
	struct teql_sched_data *q = qdisc_priv(txq->qdisc);
	struct neighbour *n = q->ncache;

	if (mn->tbl == NULL)
		return -EINVAL;
	if (n && n->tbl == mn->tbl &&
	    memcmp(n->primary_key, mn->primary_key, mn->tbl->key_len) == 0) {
		atomic_inc(&n->refcnt);
	} else {
		n = __neigh_lookup_errno(mn->tbl, mn->primary_key, dev);
		if (IS_ERR(n))
			return PTR_ERR(n);
	}
	if (neigh_event_send(n, skb_res) == 0) {
		int err;
		char haddr[MAX_ADDR_LEN];

		neigh_ha_snapshot(haddr, n, dev);
		err = dev_hard_header(skb, dev, ntohs(skb->protocol), haddr,
				      NULL, skb->len);

		if (err < 0) {
			neigh_release(n);
			return -EINVAL;
		}
		teql_neigh_release(xchg(&q->ncache, n));
		return 0;
	}
	neigh_release(n);
	return (skb_res == NULL) ? -EAGAIN : 1;
}