Esempio n. 1
0
static int
isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
{
	struct ip_tunnel_prl_entry *p;
	int ok = 1;

	read_lock(&ipip6_lock);
	p = __ipip6_tunnel_locate_prl(t, iph->saddr);
	if (p) {
		if (p->flags & PRL_DEFAULT)
			skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
		else
			skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
	} else {
		struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
		if (ipv6_addr_is_isatap(addr6) &&
		    (addr6->s6_addr32[3] == iph->saddr) &&
		    ipv6_chk_prefix(addr6, t->dev))
			skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
		else
			ok = 0;
	}
	read_unlock(&ipip6_lock);
	return ok;
}
int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct net_device *dev = NULL;
	struct inet6_dev *idev;
	struct ipv6_ac_socklist *pac;
	struct net *net = sock_net(sk);
	int	ishost = !net->ipv6.devconf_all->forwarding;
	int	err = 0;

	if (!capable(CAP_NET_ADMIN))
		return -EPERM;
	if (ipv6_addr_is_multicast(addr))
		return -EINVAL;
	if (ipv6_chk_addr(net, addr, NULL, 0))
		return -EINVAL;

	pac = sock_kmalloc(sk, sizeof(struct ipv6_ac_socklist), GFP_KERNEL);
	if (pac == NULL)
		return -ENOMEM;
	pac->acl_next = NULL;
	pac->acl_addr = *addr;

	rcu_read_lock();
	if (ifindex == 0) {
		struct rt6_info *rt;

		rt = rt6_lookup(net, addr, NULL, 0, 0);
		if (rt) {
			dev = rt->dst.dev;
			dst_release(&rt->dst);
		} else if (ishost) {
			err = -EADDRNOTAVAIL;
			goto error;
		} else {
			/* router, no matching interface: just pick one */
			dev = dev_get_by_flags_rcu(net, IFF_UP,
						   IFF_UP | IFF_LOOPBACK);
		}
	} else
		dev = dev_get_by_index_rcu(net, ifindex);

	if (dev == NULL) {
		err = -ENODEV;
		goto error;
	}

	idev = __in6_dev_get(dev);
	if (!idev) {
		if (ifindex)
			err = -ENODEV;
		else
			err = -EADDRNOTAVAIL;
		goto error;
	}
	/* reset ishost, now that we have a specific device */
	ishost = !idev->cnf.forwarding;

	pac->acl_ifindex = dev->ifindex;

	/* XXX
	 * For hosts, allow link-local or matching prefix anycasts.
	 * This obviates the need for propagating anycast routes while
	 * still allowing some non-router anycast participation.
	 */
	if (!ipv6_chk_prefix(addr, dev)) {
		if (ishost)
			err = -EADDRNOTAVAIL;
		if (err)
			goto error;
	}

	err = ipv6_dev_ac_inc(dev, addr);
	if (!err) {
		write_lock_bh(&ipv6_sk_ac_lock);
		pac->acl_next = np->ipv6_ac_list;
		np->ipv6_ac_list = pac;
		write_unlock_bh(&ipv6_sk_ac_lock);
		pac = NULL;
	}

error:
	rcu_read_unlock();
	if (pac)
		sock_kfree_s(sk, pac, sizeof(*pac));
	return err;
}