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![Li Qiong](/assets/img/avatar_default.png)
Add a 'default' case in case return a uninitialized value of ret, this should not ever happen since the follow transmit path types: - FLOW_OFFLOAD_XMIT_UNSPEC - FLOW_OFFLOAD_XMIT_TC are never observed from this path. Add this check for safety reasons. Signed-off-by: Li Qiong <liqiong@nfschina.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
697 lines
17 KiB
C
697 lines
17 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/netfilter.h>
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#include <linux/rhashtable.h>
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#include <linux/ip.h>
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#include <linux/ipv6.h>
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#include <linux/netdevice.h>
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#include <linux/if_ether.h>
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#include <net/ip.h>
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#include <net/ipv6.h>
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#include <net/ip6_route.h>
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#include <net/neighbour.h>
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#include <net/netfilter/nf_flow_table.h>
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#include <net/netfilter/nf_conntrack_acct.h>
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/* For layer 4 checksum field offset. */
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#include <linux/tcp.h>
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#include <linux/udp.h>
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static int nf_flow_state_check(struct flow_offload *flow, int proto,
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struct sk_buff *skb, unsigned int thoff)
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{
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struct tcphdr *tcph;
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if (proto != IPPROTO_TCP)
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return 0;
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tcph = (void *)(skb_network_header(skb) + thoff);
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if (unlikely(tcph->fin || tcph->rst)) {
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flow_offload_teardown(flow);
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return -1;
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}
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return 0;
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}
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static void nf_flow_nat_ip_tcp(struct sk_buff *skb, unsigned int thoff,
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__be32 addr, __be32 new_addr)
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{
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struct tcphdr *tcph;
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tcph = (void *)(skb_network_header(skb) + thoff);
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inet_proto_csum_replace4(&tcph->check, skb, addr, new_addr, true);
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}
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static void nf_flow_nat_ip_udp(struct sk_buff *skb, unsigned int thoff,
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__be32 addr, __be32 new_addr)
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{
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struct udphdr *udph;
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udph = (void *)(skb_network_header(skb) + thoff);
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if (udph->check || skb->ip_summed == CHECKSUM_PARTIAL) {
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inet_proto_csum_replace4(&udph->check, skb, addr,
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new_addr, true);
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if (!udph->check)
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udph->check = CSUM_MANGLED_0;
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}
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}
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static void nf_flow_nat_ip_l4proto(struct sk_buff *skb, struct iphdr *iph,
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unsigned int thoff, __be32 addr,
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__be32 new_addr)
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{
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switch (iph->protocol) {
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case IPPROTO_TCP:
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nf_flow_nat_ip_tcp(skb, thoff, addr, new_addr);
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break;
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case IPPROTO_UDP:
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nf_flow_nat_ip_udp(skb, thoff, addr, new_addr);
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break;
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}
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}
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static void nf_flow_snat_ip(const struct flow_offload *flow,
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struct sk_buff *skb, struct iphdr *iph,
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unsigned int thoff, enum flow_offload_tuple_dir dir)
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{
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__be32 addr, new_addr;
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switch (dir) {
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case FLOW_OFFLOAD_DIR_ORIGINAL:
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addr = iph->saddr;
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new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v4.s_addr;
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iph->saddr = new_addr;
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break;
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case FLOW_OFFLOAD_DIR_REPLY:
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addr = iph->daddr;
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new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v4.s_addr;
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iph->daddr = new_addr;
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break;
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}
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csum_replace4(&iph->check, addr, new_addr);
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nf_flow_nat_ip_l4proto(skb, iph, thoff, addr, new_addr);
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}
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static void nf_flow_dnat_ip(const struct flow_offload *flow,
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struct sk_buff *skb, struct iphdr *iph,
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unsigned int thoff, enum flow_offload_tuple_dir dir)
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{
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__be32 addr, new_addr;
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switch (dir) {
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case FLOW_OFFLOAD_DIR_ORIGINAL:
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addr = iph->daddr;
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new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v4.s_addr;
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iph->daddr = new_addr;
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break;
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case FLOW_OFFLOAD_DIR_REPLY:
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addr = iph->saddr;
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new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v4.s_addr;
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iph->saddr = new_addr;
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break;
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}
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csum_replace4(&iph->check, addr, new_addr);
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nf_flow_nat_ip_l4proto(skb, iph, thoff, addr, new_addr);
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}
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static void nf_flow_nat_ip(const struct flow_offload *flow, struct sk_buff *skb,
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unsigned int thoff, enum flow_offload_tuple_dir dir,
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struct iphdr *iph)
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{
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if (test_bit(NF_FLOW_SNAT, &flow->flags)) {
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nf_flow_snat_port(flow, skb, thoff, iph->protocol, dir);
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nf_flow_snat_ip(flow, skb, iph, thoff, dir);
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}
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if (test_bit(NF_FLOW_DNAT, &flow->flags)) {
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nf_flow_dnat_port(flow, skb, thoff, iph->protocol, dir);
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nf_flow_dnat_ip(flow, skb, iph, thoff, dir);
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}
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}
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static bool ip_has_options(unsigned int thoff)
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{
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return thoff != sizeof(struct iphdr);
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}
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static void nf_flow_tuple_encap(struct sk_buff *skb,
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struct flow_offload_tuple *tuple)
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{
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struct vlan_ethhdr *veth;
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struct pppoe_hdr *phdr;
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int i = 0;
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if (skb_vlan_tag_present(skb)) {
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tuple->encap[i].id = skb_vlan_tag_get(skb);
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tuple->encap[i].proto = skb->vlan_proto;
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i++;
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}
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switch (skb->protocol) {
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case htons(ETH_P_8021Q):
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veth = (struct vlan_ethhdr *)skb_mac_header(skb);
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tuple->encap[i].id = ntohs(veth->h_vlan_TCI);
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tuple->encap[i].proto = skb->protocol;
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break;
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case htons(ETH_P_PPP_SES):
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phdr = (struct pppoe_hdr *)skb_mac_header(skb);
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tuple->encap[i].id = ntohs(phdr->sid);
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tuple->encap[i].proto = skb->protocol;
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break;
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}
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}
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static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
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struct flow_offload_tuple *tuple, u32 *hdrsize,
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u32 offset)
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{
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struct flow_ports *ports;
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unsigned int thoff;
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struct iphdr *iph;
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u8 ipproto;
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if (!pskb_may_pull(skb, sizeof(*iph) + offset))
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return -1;
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iph = (struct iphdr *)(skb_network_header(skb) + offset);
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thoff = (iph->ihl * 4);
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if (ip_is_fragment(iph) ||
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unlikely(ip_has_options(thoff)))
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return -1;
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thoff += offset;
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ipproto = iph->protocol;
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switch (ipproto) {
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case IPPROTO_TCP:
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*hdrsize = sizeof(struct tcphdr);
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break;
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case IPPROTO_UDP:
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*hdrsize = sizeof(struct udphdr);
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break;
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#ifdef CONFIG_NF_CT_PROTO_GRE
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case IPPROTO_GRE:
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*hdrsize = sizeof(struct gre_base_hdr);
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break;
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#endif
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default:
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return -1;
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}
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if (iph->ttl <= 1)
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return -1;
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if (!pskb_may_pull(skb, thoff + *hdrsize))
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return -1;
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switch (ipproto) {
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case IPPROTO_TCP:
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case IPPROTO_UDP:
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ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
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tuple->src_port = ports->source;
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tuple->dst_port = ports->dest;
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break;
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case IPPROTO_GRE: {
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struct gre_base_hdr *greh;
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greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
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if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
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return -1;
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break;
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}
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}
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iph = (struct iphdr *)(skb_network_header(skb) + offset);
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tuple->src_v4.s_addr = iph->saddr;
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tuple->dst_v4.s_addr = iph->daddr;
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tuple->l3proto = AF_INET;
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tuple->l4proto = ipproto;
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tuple->iifidx = dev->ifindex;
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nf_flow_tuple_encap(skb, tuple);
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return 0;
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}
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/* Based on ip_exceeds_mtu(). */
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static bool nf_flow_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
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{
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if (skb->len <= mtu)
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return false;
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if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
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return false;
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return true;
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}
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static inline bool nf_flow_dst_check(struct flow_offload_tuple *tuple)
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{
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if (tuple->xmit_type != FLOW_OFFLOAD_XMIT_NEIGH &&
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tuple->xmit_type != FLOW_OFFLOAD_XMIT_XFRM)
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return true;
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return dst_check(tuple->dst_cache, tuple->dst_cookie);
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}
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static unsigned int nf_flow_xmit_xfrm(struct sk_buff *skb,
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const struct nf_hook_state *state,
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struct dst_entry *dst)
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{
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skb_orphan(skb);
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skb_dst_set_noref(skb, dst);
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dst_output(state->net, state->sk, skb);
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return NF_STOLEN;
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}
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static bool nf_flow_skb_encap_protocol(const struct sk_buff *skb, __be16 proto,
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u32 *offset)
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{
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struct vlan_ethhdr *veth;
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switch (skb->protocol) {
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case htons(ETH_P_8021Q):
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veth = (struct vlan_ethhdr *)skb_mac_header(skb);
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if (veth->h_vlan_encapsulated_proto == proto) {
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*offset += VLAN_HLEN;
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return true;
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}
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break;
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case htons(ETH_P_PPP_SES):
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if (nf_flow_pppoe_proto(skb) == proto) {
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*offset += PPPOE_SES_HLEN;
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return true;
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}
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break;
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}
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return false;
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}
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static void nf_flow_encap_pop(struct sk_buff *skb,
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struct flow_offload_tuple_rhash *tuplehash)
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{
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struct vlan_hdr *vlan_hdr;
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int i;
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for (i = 0; i < tuplehash->tuple.encap_num; i++) {
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if (skb_vlan_tag_present(skb)) {
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__vlan_hwaccel_clear_tag(skb);
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continue;
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}
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switch (skb->protocol) {
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case htons(ETH_P_8021Q):
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vlan_hdr = (struct vlan_hdr *)skb->data;
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__skb_pull(skb, VLAN_HLEN);
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vlan_set_encap_proto(skb, vlan_hdr);
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skb_reset_network_header(skb);
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break;
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case htons(ETH_P_PPP_SES):
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skb->protocol = nf_flow_pppoe_proto(skb);
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skb_pull(skb, PPPOE_SES_HLEN);
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skb_reset_network_header(skb);
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break;
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}
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}
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}
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static unsigned int nf_flow_queue_xmit(struct net *net, struct sk_buff *skb,
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const struct flow_offload_tuple_rhash *tuplehash,
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unsigned short type)
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{
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struct net_device *outdev;
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outdev = dev_get_by_index_rcu(net, tuplehash->tuple.out.ifidx);
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if (!outdev)
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return NF_DROP;
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skb->dev = outdev;
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dev_hard_header(skb, skb->dev, type, tuplehash->tuple.out.h_dest,
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tuplehash->tuple.out.h_source, skb->len);
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dev_queue_xmit(skb);
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return NF_STOLEN;
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}
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unsigned int
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nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
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const struct nf_hook_state *state)
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{
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struct flow_offload_tuple_rhash *tuplehash;
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struct nf_flowtable *flow_table = priv;
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struct flow_offload_tuple tuple = {};
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enum flow_offload_tuple_dir dir;
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struct flow_offload *flow;
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struct net_device *outdev;
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u32 hdrsize, offset = 0;
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unsigned int thoff, mtu;
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struct rtable *rt;
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struct iphdr *iph;
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__be32 nexthop;
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int ret;
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if (skb->protocol != htons(ETH_P_IP) &&
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!nf_flow_skb_encap_protocol(skb, htons(ETH_P_IP), &offset))
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return NF_ACCEPT;
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if (nf_flow_tuple_ip(skb, state->in, &tuple, &hdrsize, offset) < 0)
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return NF_ACCEPT;
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tuplehash = flow_offload_lookup(flow_table, &tuple);
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if (tuplehash == NULL)
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return NF_ACCEPT;
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dir = tuplehash->tuple.dir;
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flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
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mtu = flow->tuplehash[dir].tuple.mtu + offset;
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if (unlikely(nf_flow_exceeds_mtu(skb, mtu)))
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return NF_ACCEPT;
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iph = (struct iphdr *)(skb_network_header(skb) + offset);
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thoff = (iph->ihl * 4) + offset;
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if (nf_flow_state_check(flow, iph->protocol, skb, thoff))
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return NF_ACCEPT;
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if (!nf_flow_dst_check(&tuplehash->tuple)) {
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flow_offload_teardown(flow);
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return NF_ACCEPT;
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}
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if (skb_try_make_writable(skb, thoff + hdrsize))
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return NF_DROP;
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flow_offload_refresh(flow_table, flow);
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nf_flow_encap_pop(skb, tuplehash);
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thoff -= offset;
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iph = ip_hdr(skb);
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nf_flow_nat_ip(flow, skb, thoff, dir, iph);
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ip_decrease_ttl(iph);
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skb_clear_tstamp(skb);
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if (flow_table->flags & NF_FLOWTABLE_COUNTER)
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nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len);
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if (unlikely(tuplehash->tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)) {
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rt = (struct rtable *)tuplehash->tuple.dst_cache;
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memset(skb->cb, 0, sizeof(struct inet_skb_parm));
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IPCB(skb)->iif = skb->dev->ifindex;
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IPCB(skb)->flags = IPSKB_FORWARDED;
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return nf_flow_xmit_xfrm(skb, state, &rt->dst);
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}
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switch (tuplehash->tuple.xmit_type) {
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case FLOW_OFFLOAD_XMIT_NEIGH:
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rt = (struct rtable *)tuplehash->tuple.dst_cache;
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outdev = rt->dst.dev;
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skb->dev = outdev;
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nexthop = rt_nexthop(rt, flow->tuplehash[!dir].tuple.src_v4.s_addr);
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skb_dst_set_noref(skb, &rt->dst);
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neigh_xmit(NEIGH_ARP_TABLE, outdev, &nexthop, skb);
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ret = NF_STOLEN;
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break;
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case FLOW_OFFLOAD_XMIT_DIRECT:
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ret = nf_flow_queue_xmit(state->net, skb, tuplehash, ETH_P_IP);
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if (ret == NF_DROP)
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flow_offload_teardown(flow);
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break;
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default:
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WARN_ON_ONCE(1);
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ret = NF_DROP;
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break;
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(nf_flow_offload_ip_hook);
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static void nf_flow_nat_ipv6_tcp(struct sk_buff *skb, unsigned int thoff,
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struct in6_addr *addr,
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struct in6_addr *new_addr,
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struct ipv6hdr *ip6h)
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{
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struct tcphdr *tcph;
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tcph = (void *)(skb_network_header(skb) + thoff);
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inet_proto_csum_replace16(&tcph->check, skb, addr->s6_addr32,
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new_addr->s6_addr32, true);
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}
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static void nf_flow_nat_ipv6_udp(struct sk_buff *skb, unsigned int thoff,
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struct in6_addr *addr,
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struct in6_addr *new_addr)
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{
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struct udphdr *udph;
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udph = (void *)(skb_network_header(skb) + thoff);
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if (udph->check || skb->ip_summed == CHECKSUM_PARTIAL) {
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inet_proto_csum_replace16(&udph->check, skb, addr->s6_addr32,
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new_addr->s6_addr32, true);
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if (!udph->check)
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udph->check = CSUM_MANGLED_0;
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}
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}
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static void nf_flow_nat_ipv6_l4proto(struct sk_buff *skb, struct ipv6hdr *ip6h,
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unsigned int thoff, struct in6_addr *addr,
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struct in6_addr *new_addr)
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{
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switch (ip6h->nexthdr) {
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case IPPROTO_TCP:
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nf_flow_nat_ipv6_tcp(skb, thoff, addr, new_addr, ip6h);
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break;
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case IPPROTO_UDP:
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nf_flow_nat_ipv6_udp(skb, thoff, addr, new_addr);
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break;
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}
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}
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static void nf_flow_snat_ipv6(const struct flow_offload *flow,
|
|
struct sk_buff *skb, struct ipv6hdr *ip6h,
|
|
unsigned int thoff,
|
|
enum flow_offload_tuple_dir dir)
|
|
{
|
|
struct in6_addr addr, new_addr;
|
|
|
|
switch (dir) {
|
|
case FLOW_OFFLOAD_DIR_ORIGINAL:
|
|
addr = ip6h->saddr;
|
|
new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v6;
|
|
ip6h->saddr = new_addr;
|
|
break;
|
|
case FLOW_OFFLOAD_DIR_REPLY:
|
|
addr = ip6h->daddr;
|
|
new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v6;
|
|
ip6h->daddr = new_addr;
|
|
break;
|
|
}
|
|
|
|
nf_flow_nat_ipv6_l4proto(skb, ip6h, thoff, &addr, &new_addr);
|
|
}
|
|
|
|
static void nf_flow_dnat_ipv6(const struct flow_offload *flow,
|
|
struct sk_buff *skb, struct ipv6hdr *ip6h,
|
|
unsigned int thoff,
|
|
enum flow_offload_tuple_dir dir)
|
|
{
|
|
struct in6_addr addr, new_addr;
|
|
|
|
switch (dir) {
|
|
case FLOW_OFFLOAD_DIR_ORIGINAL:
|
|
addr = ip6h->daddr;
|
|
new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v6;
|
|
ip6h->daddr = new_addr;
|
|
break;
|
|
case FLOW_OFFLOAD_DIR_REPLY:
|
|
addr = ip6h->saddr;
|
|
new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v6;
|
|
ip6h->saddr = new_addr;
|
|
break;
|
|
}
|
|
|
|
nf_flow_nat_ipv6_l4proto(skb, ip6h, thoff, &addr, &new_addr);
|
|
}
|
|
|
|
static void nf_flow_nat_ipv6(const struct flow_offload *flow,
|
|
struct sk_buff *skb,
|
|
enum flow_offload_tuple_dir dir,
|
|
struct ipv6hdr *ip6h)
|
|
{
|
|
unsigned int thoff = sizeof(*ip6h);
|
|
|
|
if (test_bit(NF_FLOW_SNAT, &flow->flags)) {
|
|
nf_flow_snat_port(flow, skb, thoff, ip6h->nexthdr, dir);
|
|
nf_flow_snat_ipv6(flow, skb, ip6h, thoff, dir);
|
|
}
|
|
if (test_bit(NF_FLOW_DNAT, &flow->flags)) {
|
|
nf_flow_dnat_port(flow, skb, thoff, ip6h->nexthdr, dir);
|
|
nf_flow_dnat_ipv6(flow, skb, ip6h, thoff, dir);
|
|
}
|
|
}
|
|
|
|
static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
|
|
struct flow_offload_tuple *tuple, u32 *hdrsize,
|
|
u32 offset)
|
|
{
|
|
struct flow_ports *ports;
|
|
struct ipv6hdr *ip6h;
|
|
unsigned int thoff;
|
|
u8 nexthdr;
|
|
|
|
thoff = sizeof(*ip6h) + offset;
|
|
if (!pskb_may_pull(skb, thoff))
|
|
return -1;
|
|
|
|
ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
|
|
|
|
nexthdr = ip6h->nexthdr;
|
|
switch (nexthdr) {
|
|
case IPPROTO_TCP:
|
|
*hdrsize = sizeof(struct tcphdr);
|
|
break;
|
|
case IPPROTO_UDP:
|
|
*hdrsize = sizeof(struct udphdr);
|
|
break;
|
|
#ifdef CONFIG_NF_CT_PROTO_GRE
|
|
case IPPROTO_GRE:
|
|
*hdrsize = sizeof(struct gre_base_hdr);
|
|
break;
|
|
#endif
|
|
default:
|
|
return -1;
|
|
}
|
|
|
|
if (ip6h->hop_limit <= 1)
|
|
return -1;
|
|
|
|
if (!pskb_may_pull(skb, thoff + *hdrsize))
|
|
return -1;
|
|
|
|
switch (nexthdr) {
|
|
case IPPROTO_TCP:
|
|
case IPPROTO_UDP:
|
|
ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
|
|
tuple->src_port = ports->source;
|
|
tuple->dst_port = ports->dest;
|
|
break;
|
|
case IPPROTO_GRE: {
|
|
struct gre_base_hdr *greh;
|
|
|
|
greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
|
|
if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
|
|
return -1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
|
|
|
|
tuple->src_v6 = ip6h->saddr;
|
|
tuple->dst_v6 = ip6h->daddr;
|
|
tuple->l3proto = AF_INET6;
|
|
tuple->l4proto = nexthdr;
|
|
tuple->iifidx = dev->ifindex;
|
|
nf_flow_tuple_encap(skb, tuple);
|
|
|
|
return 0;
|
|
}
|
|
|
|
unsigned int
|
|
nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
struct flow_offload_tuple_rhash *tuplehash;
|
|
struct nf_flowtable *flow_table = priv;
|
|
struct flow_offload_tuple tuple = {};
|
|
enum flow_offload_tuple_dir dir;
|
|
const struct in6_addr *nexthop;
|
|
struct flow_offload *flow;
|
|
struct net_device *outdev;
|
|
unsigned int thoff, mtu;
|
|
u32 hdrsize, offset = 0;
|
|
struct ipv6hdr *ip6h;
|
|
struct rt6_info *rt;
|
|
int ret;
|
|
|
|
if (skb->protocol != htons(ETH_P_IPV6) &&
|
|
!nf_flow_skb_encap_protocol(skb, htons(ETH_P_IPV6), &offset))
|
|
return NF_ACCEPT;
|
|
|
|
if (nf_flow_tuple_ipv6(skb, state->in, &tuple, &hdrsize, offset) < 0)
|
|
return NF_ACCEPT;
|
|
|
|
tuplehash = flow_offload_lookup(flow_table, &tuple);
|
|
if (tuplehash == NULL)
|
|
return NF_ACCEPT;
|
|
|
|
dir = tuplehash->tuple.dir;
|
|
flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
|
|
|
|
mtu = flow->tuplehash[dir].tuple.mtu + offset;
|
|
if (unlikely(nf_flow_exceeds_mtu(skb, mtu)))
|
|
return NF_ACCEPT;
|
|
|
|
ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
|
|
thoff = sizeof(*ip6h) + offset;
|
|
if (nf_flow_state_check(flow, ip6h->nexthdr, skb, thoff))
|
|
return NF_ACCEPT;
|
|
|
|
if (!nf_flow_dst_check(&tuplehash->tuple)) {
|
|
flow_offload_teardown(flow);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
if (skb_try_make_writable(skb, thoff + hdrsize))
|
|
return NF_DROP;
|
|
|
|
flow_offload_refresh(flow_table, flow);
|
|
|
|
nf_flow_encap_pop(skb, tuplehash);
|
|
|
|
ip6h = ipv6_hdr(skb);
|
|
nf_flow_nat_ipv6(flow, skb, dir, ip6h);
|
|
|
|
ip6h->hop_limit--;
|
|
skb_clear_tstamp(skb);
|
|
|
|
if (flow_table->flags & NF_FLOWTABLE_COUNTER)
|
|
nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len);
|
|
|
|
if (unlikely(tuplehash->tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)) {
|
|
rt = (struct rt6_info *)tuplehash->tuple.dst_cache;
|
|
memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
|
|
IP6CB(skb)->iif = skb->dev->ifindex;
|
|
IP6CB(skb)->flags = IP6SKB_FORWARDED;
|
|
return nf_flow_xmit_xfrm(skb, state, &rt->dst);
|
|
}
|
|
|
|
switch (tuplehash->tuple.xmit_type) {
|
|
case FLOW_OFFLOAD_XMIT_NEIGH:
|
|
rt = (struct rt6_info *)tuplehash->tuple.dst_cache;
|
|
outdev = rt->dst.dev;
|
|
skb->dev = outdev;
|
|
nexthop = rt6_nexthop(rt, &flow->tuplehash[!dir].tuple.src_v6);
|
|
skb_dst_set_noref(skb, &rt->dst);
|
|
neigh_xmit(NEIGH_ND_TABLE, outdev, nexthop, skb);
|
|
ret = NF_STOLEN;
|
|
break;
|
|
case FLOW_OFFLOAD_XMIT_DIRECT:
|
|
ret = nf_flow_queue_xmit(state->net, skb, tuplehash, ETH_P_IPV6);
|
|
if (ret == NF_DROP)
|
|
flow_offload_teardown(flow);
|
|
break;
|
|
default:
|
|
WARN_ON_ONCE(1);
|
|
ret = NF_DROP;
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_flow_offload_ipv6_hook);
|