Example #1
0
static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
{
    struct ip_tunnel *tunnel = (struct ip_tunnel*)dev->priv;
    struct net_device_stats *stats = &tunnel->stat;
    struct iphdr  *tiph = &tunnel->parms.iph;
    struct ipv6hdr *iph6 = skb->nh.ipv6h;
    u8     tos = tunnel->parms.iph.tos;
    struct rtable *rt;     			/* Route to the other host */
    struct net_device *tdev;			/* Device to other host */
    struct iphdr  *iph;			/* Our new IP header */
    int    max_headroom;			/* The extra header space needed */
    u32    dst = tiph->daddr;
    int    mtu;
    struct in6_addr *addr6;
    int addr_type;

    if (tunnel->recursion++) {
        tunnel->stat.collisions++;
        goto tx_error;
    }

    if (skb->protocol != htons(ETH_P_IPV6))
        goto tx_error;

    if (!dst)
        dst = try_6to4(&iph6->daddr);

    if (!dst) {
        struct neighbour *neigh = NULL;

        if (skb->dst)
            neigh = skb->dst->neighbour;

        if (neigh == NULL) {
            if (net_ratelimit())
                printk(KERN_DEBUG "sit: nexthop == NULL\n");
            goto tx_error;
        }

        addr6 = (struct in6_addr*)&neigh->primary_key;
        addr_type = ipv6_addr_type(addr6);

        if (addr_type == IPV6_ADDR_ANY) {
            addr6 = &skb->nh.ipv6h->daddr;
            addr_type = ipv6_addr_type(addr6);
        }

        if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
            goto tx_error_icmp;

        dst = addr6->s6_addr32[3];
    }

    {
        struct flowi fl = { .nl_u = { .ip4_u =
                {   .daddr = dst,
                    .saddr = tiph->saddr,
                    .tos = RT_TOS(tos)
                }
            },
            .oif = tunnel->parms.link
        };
        if (ip_route_output_key(&rt, &fl)) {
            tunnel->stat.tx_carrier_errors++;
            goto tx_error_icmp;
        }
    }
    if (rt->rt_type != RTN_UNICAST) {
        tunnel->stat.tx_carrier_errors++;
        goto tx_error_icmp;
    }
    tdev = rt->u.dst.dev;

    if (tdev == dev) {
        ip_rt_put(rt);
        tunnel->stat.collisions++;
        goto tx_error;
    }

    if (tiph->frag_off)
        mtu = dst_pmtu(&rt->u.dst) - sizeof(struct iphdr);
    else
        mtu = skb->dst ? dst_pmtu(skb->dst) : dev->mtu;

    if (mtu < 68) {
        tunnel->stat.collisions++;
        ip_rt_put(rt);
        goto tx_error;
    }
    if (mtu < IPV6_MIN_MTU)
        mtu = IPV6_MIN_MTU;
    if (tunnel->parms.iph.daddr && skb->dst)
        skb->dst->ops->update_pmtu(skb->dst, mtu);

    if (skb->len > mtu) {
        icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
        ip_rt_put(rt);
        goto tx_error;
    }

    if (tunnel->err_count > 0) {
        if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
            tunnel->err_count--;
            dst_link_failure(skb);
        } else
            tunnel->err_count = 0;
    }

    skb->h.raw = skb->nh.raw;

    /*
     * Okay, now see if we can stuff it in the buffer as-is.
     */
    max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);

    if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
        struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
        if (!new_skb) {
            ip_rt_put(rt);
            stats->tx_dropped++;
            dev_kfree_skb(skb);
            tunnel->recursion--;
            return 0;
        }
        if (skb->sk)
            skb_set_owner_w(new_skb, skb->sk);
        dev_kfree_skb(skb);
        skb = new_skb;
        iph6 = skb->nh.ipv6h;
    }

    skb->nh.raw = skb_push(skb, sizeof(struct iphdr));
    memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
    dst_release(skb->dst);
    skb->dst = &rt->u.dst;

    /*
     *	Push down and install the IPIP header.
     */

    iph 			=	skb->nh.iph;
    iph->version		=	4;
    iph->ihl		=	sizeof(struct iphdr)>>2;
    if (mtu > IPV6_MIN_MTU)
        iph->frag_off	=	htons(IP_DF);
    else
        iph->frag_off	=	0;

    iph->protocol		=	IPPROTO_IPV6;
    iph->tos		=	INET_ECN_encapsulate(tos, ip6_get_dsfield(iph6));
    iph->daddr		=	rt->rt_dst;
    iph->saddr		=	rt->rt_src;

    if ((iph->ttl = tiph->ttl) == 0)
        iph->ttl	=	iph6->hop_limit;

#ifdef CONFIG_NETFILTER
    nf_conntrack_put(skb->nfct);
    skb->nfct = NULL;
#ifdef CONFIG_NETFILTER_DEBUG
    skb->nf_debug = 0;
#endif
#endif

    IPTUNNEL_XMIT();
    tunnel->recursion--;
    return 0;

tx_error_icmp:
    dst_link_failure(skb);
tx_error:
    stats->tx_errors++;
    dev_kfree_skb(skb);
    tunnel->recursion--;
    return 0;
}
Example #2
0
static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
				     struct net_device *dev)
{
	struct ip_tunnel *tunnel = netdev_priv(dev);
	struct net_device_stats *stats = &tunnel->dev->stats;
	struct iphdr  *tiph = &tunnel->parms.iph;
	struct ipv6hdr *iph6 = ipv6_hdr(skb);
	u8     tos = tunnel->parms.iph.tos;
	struct rtable *rt;     			/* Route to the other host */
	struct net_device *tdev;			/* Device to other host */
	struct iphdr  *iph;			/* Our new IP header */
	unsigned int max_headroom;		/* The extra header space needed */
	__be32 dst = tiph->daddr;
	int    mtu;
	struct in6_addr *addr6;
	int addr_type;

	if (skb->protocol != htons(ETH_P_IPV6))
		goto tx_error;

	/* ISATAP (RFC4214) - must come before 6to4 */
	if (dev->priv_flags & IFF_ISATAP) {
		struct neighbour *neigh = NULL;

		if (skb_dst(skb))
			neigh = skb_dst(skb)->neighbour;

		if (neigh == NULL) {
			if (net_ratelimit())
				printk(KERN_DEBUG "sit: nexthop == NULL\n");
			goto tx_error;
		}

		addr6 = (struct in6_addr*)&neigh->primary_key;
		addr_type = ipv6_addr_type(addr6);

		if ((addr_type & IPV6_ADDR_UNICAST) &&
		     ipv6_addr_is_isatap(addr6))
			dst = addr6->s6_addr32[3];
		else
			goto tx_error;
	}

	if (!dst)
		dst = try_6to4(&iph6->daddr);

	if (!dst) {
		struct neighbour *neigh = NULL;

		if (skb_dst(skb))
			neigh = skb_dst(skb)->neighbour;

		if (neigh == NULL) {
			if (net_ratelimit())
				printk(KERN_DEBUG "sit: nexthop == NULL\n");
			goto tx_error;
		}

		addr6 = (struct in6_addr*)&neigh->primary_key;
		addr_type = ipv6_addr_type(addr6);

		if (addr_type == IPV6_ADDR_ANY) {
			addr6 = &ipv6_hdr(skb)->daddr;
			addr_type = ipv6_addr_type(addr6);
		}

		if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
			goto tx_error_icmp;

		dst = addr6->s6_addr32[3];
	}

	{
		struct flowi fl = { .nl_u = { .ip4_u =
					      { .daddr = dst,
						.saddr = tiph->saddr,
						.tos = RT_TOS(tos) } },
				    .oif = tunnel->parms.link,
				    .proto = IPPROTO_IPV6 };
		if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
			stats->tx_carrier_errors++;
			goto tx_error_icmp;
		}
	}
	if (rt->rt_type != RTN_UNICAST) {
		ip_rt_put(rt);
		stats->tx_carrier_errors++;
		goto tx_error_icmp;
	}
	tdev = rt->u.dst.dev;

	if (tdev == dev) {
		ip_rt_put(rt);
		stats->collisions++;
		goto tx_error;
	}

	if (tiph->frag_off)
		mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
	else
		mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;

	if (mtu < 68) {
		stats->collisions++;
		ip_rt_put(rt);
		goto tx_error;
	}
	if (mtu < IPV6_MIN_MTU)
		mtu = IPV6_MIN_MTU;
	if (tunnel->parms.iph.daddr && skb_dst(skb))
		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);

	if (skb->len > mtu) {
		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
		ip_rt_put(rt);
		goto tx_error;
	}

	if (tunnel->err_count > 0) {
		if (time_before(jiffies,
				tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
			tunnel->err_count--;
			dst_link_failure(skb);
		} else
			tunnel->err_count = 0;
	}

	/*
	 * Okay, now see if we can stuff it in the buffer as-is.
	 */
	max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);

	if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
	    (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
		struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
		if (!new_skb) {
			ip_rt_put(rt);
			stats->tx_dropped++;
			dev_kfree_skb(skb);
			return NETDEV_TX_OK;
		}
		if (skb->sk)
			skb_set_owner_w(new_skb, skb->sk);
		dev_kfree_skb(skb);
		skb = new_skb;
		iph6 = ipv6_hdr(skb);
	}

	skb->transport_header = skb->network_header;
	skb_push(skb, sizeof(struct iphdr));
	skb_reset_network_header(skb);
	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
	IPCB(skb)->flags = 0;
	skb_dst_drop(skb);
	skb_dst_set(skb, &rt->u.dst);

	/*
	 *	Push down and install the IPIP header.
	 */

	iph 			=	ip_hdr(skb);
	iph->version		=	4;
	iph->ihl		=	sizeof(struct iphdr)>>2;
	if (mtu > IPV6_MIN_MTU)
		iph->frag_off	=	tiph->frag_off;
	else
		iph->frag_off	=	0;

	iph->protocol		=	IPPROTO_IPV6;
	iph->tos		=	INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
	iph->daddr		=	rt->rt_dst;
	iph->saddr		=	rt->rt_src;

	if ((iph->ttl = tiph->ttl) == 0)
		iph->ttl	=	iph6->hop_limit;

	nf_reset(skb);

	IPTUNNEL_XMIT();
	return NETDEV_TX_OK;

tx_error_icmp:
	dst_link_failure(skb);
tx_error:
	stats->tx_errors++;
	dev_kfree_skb(skb);
	return NETDEV_TX_OK;
}