static int br_nf_pre_routing_finish(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
	struct iphdr *iph = skb->nh.iph;
	struct nf_bridge_info *nf_bridge = skb->nf_bridge;

#ifdef CONFIG_NETFILTER_DEBUG
	skb->nf_debug ^= (1 << NF_BR_PRE_ROUTING);
#endif

	if (nf_bridge->mask & BRNF_PKT_TYPE) {
		skb->pkt_type = PACKET_OTHERHOST;
		nf_bridge->mask ^= BRNF_PKT_TYPE;
	}
	nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING;

	if (dnat_took_place(skb)) {
		if (ip_route_input(skb, iph->daddr, iph->saddr, iph->tos,
		    dev)) {
			struct rtable *rt;
			struct flowi fl = { .nl_u = 
			{ .ip4_u = { .daddr = iph->daddr, .saddr = 0 ,
				     .tos = RT_TOS(iph->tos)} }, .proto = 0};

			if (!ip_route_output_key(&rt, &fl)) {
				/* Bridged-and-DNAT'ed traffic doesn't
				 * require ip_forwarding. */
				if (((struct dst_entry *)rt)->dev == dev) {
					skb->dst = (struct dst_entry *)rt;
					goto bridged_dnat;
				}
				__br_dnat_complain();
				dst_release((struct dst_entry *)rt);
			}
			kfree_skb(skb);
			return 0;
		} else {
			if (skb->dst->dev == dev) {
bridged_dnat:
				/* Tell br_nf_local_out this is a
				 * bridged frame */
				nf_bridge->mask |= BRNF_BRIDGED_DNAT;
				skb->dev = nf_bridge->physindev;
				if (skb->protocol ==
				    __constant_htons(ETH_P_8021Q)) {
					skb_push(skb, VLAN_HLEN);
					skb->nh.raw -= VLAN_HLEN;
				}
				NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING,
					       skb, skb->dev, NULL,
					       br_nf_pre_routing_finish_bridge,
					       1);
				return 0;
			}
			memcpy(eth_hdr(skb)->h_dest, dev->dev_addr,
			       ETH_ALEN);
			skb->pkt_type = PACKET_HOST;
		}
	} else {
Exemple #2
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static int br_nf_pre_routing_finish(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
	struct iphdr *iph = ip_hdr(skb);
	struct nf_bridge_info *nf_bridge = skb->nf_bridge;
	int err;

	if (nf_bridge->mask & BRNF_PKT_TYPE) {
		skb->pkt_type = PACKET_OTHERHOST;
		nf_bridge->mask ^= BRNF_PKT_TYPE;
	}
	nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING;
	if (dnat_took_place(skb)) {
		if ((err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev))) {
			struct rtable *rt;
			struct flowi fl = {
				.nl_u = {
					.ip4_u = {
						 .daddr = iph->daddr,
						 .saddr = 0,
						 .tos = RT_TOS(iph->tos) },
				},
				.proto = 0,
			};
			struct in_device *in_dev = in_dev_get(dev);

			/* If err equals -EHOSTUNREACH the error is due to a
			 * martian destination or due to the fact that
			 * forwarding is disabled. For most martian packets,
			 * ip_route_output_key() will fail. It won't fail for 2 types of
			 * martian destinations: loopback destinations and destination
			 * 0.0.0.0. In both cases the packet will be dropped because the
			 * destination is the loopback device and not the bridge. */
			if (err != -EHOSTUNREACH || !in_dev || IN_DEV_FORWARD(in_dev))
				goto free_skb;

			if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
				/* - Bridged-and-DNAT'ed traffic doesn't
				 *   require ip_forwarding. */
				if (((struct dst_entry *)rt)->dev == dev) {
					skb->dst = (struct dst_entry *)rt;
					goto bridged_dnat;
				}
				/* we are sure that forwarding is disabled, so printing
				 * this message is no problem. Note that the packet could
				 * still have a martian destination address, in which case
				 * the packet could be dropped even if forwarding were enabled */
				__br_dnat_complain();
				dst_release((struct dst_entry *)rt);
			}
free_skb:
			kfree_skb(skb);
			return 0;
		} else {
			if (skb->dst->dev == dev) {
bridged_dnat:
				/* Tell br_nf_local_out this is a
				 * bridged frame */
				nf_bridge->mask |= BRNF_BRIDGED_DNAT;
				skb->dev = nf_bridge->physindev;
				nf_bridge_push_encap_header(skb);
				NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING,
					       skb, skb->dev, NULL,
					       br_nf_pre_routing_finish_bridge,
					       1);
				return 0;
			}
			memcpy(eth_hdr(skb)->h_dest, dev->dev_addr, ETH_ALEN);
			skb->pkt_type = PACKET_HOST;
		}
	} else {