#include <uapi/linux/if_ether.h>
#include <uapi/linux/if_packet.h>
#include <uapi/linux/ip.h>
+#include <uapi/linux/ipv6.h>
#include <uapi/linux/in.h>
#include <uapi/linux/tcp.h>
#include <uapi/linux/filter.h>
#include <uapi/linux/pkt_cls.h>
+#include <net/ipv6.h>
#include "bpf_helpers.h"
+#define _htonl __builtin_bswap32
#define ERROR(ret) do {\
char fmt[] = "ERROR line:%d ret:%d\n";\
bpf_trace_printk(fmt, sizeof(fmt), __LINE__, ret); \
return TC_ACT_OK;
}
+SEC("ipip6_set_tunnel")
+int _ipip6_set_tunnel(struct __sk_buff *skb)
+{
+ struct bpf_tunnel_key key = {};
+ void *data = (void *)(long)skb->data;
+ struct iphdr *iph = data;
+ struct tcphdr *tcp = data + sizeof(*iph);
+ void *data_end = (void *)(long)skb->data_end;
+ int ret;
+
+ /* single length check */
+ if (data + sizeof(*iph) + sizeof(*tcp) > data_end) {
+ ERROR(1);
+ return TC_ACT_SHOT;
+ }
+
+ key.remote_ipv6[0] = _htonl(0x2401db00);
+ key.tunnel_ttl = 64;
+
+ if (iph->protocol == IPPROTO_ICMP) {
+ key.remote_ipv6[3] = _htonl(1);
+ } else {
+ if (iph->protocol != IPPROTO_TCP || iph->ihl != 5) {
+ ERROR(iph->protocol);
+ return TC_ACT_SHOT;
+ }
+
+ if (tcp->dest == htons(5200)) {
+ key.remote_ipv6[3] = _htonl(1);
+ } else if (tcp->dest == htons(5201)) {
+ key.remote_ipv6[3] = _htonl(2);
+ } else {
+ ERROR(tcp->dest);
+ return TC_ACT_SHOT;
+ }
+ }
+
+ ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+ if (ret < 0) {
+ ERROR(ret);
+ return TC_ACT_SHOT;
+ }
+
+ return TC_ACT_OK;
+}
+
+SEC("ipip6_get_tunnel")
+int _ipip6_get_tunnel(struct __sk_buff *skb)
+{
+ int ret;
+ struct bpf_tunnel_key key;
+ char fmt[] = "remote ip6 %x::%x\n";
+
+ ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+ if (ret < 0) {
+ ERROR(ret);
+ return TC_ACT_SHOT;
+ }
+
+ bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
+ _htonl(key.remote_ipv6[3]));
+ return TC_ACT_OK;
+}
+
+SEC("ip6ip6_set_tunnel")
+int _ip6ip6_set_tunnel(struct __sk_buff *skb)
+{
+ struct bpf_tunnel_key key = {};
+ void *data = (void *)(long)skb->data;
+ struct ipv6hdr *iph = data;
+ struct tcphdr *tcp = data + sizeof(*iph);
+ void *data_end = (void *)(long)skb->data_end;
+ int ret;
+
+ /* single length check */
+ if (data + sizeof(*iph) + sizeof(*tcp) > data_end) {
+ ERROR(1);
+ return TC_ACT_SHOT;
+ }
+
+ key.remote_ipv6[0] = _htonl(0x2401db00);
+ key.tunnel_ttl = 64;
+
+ if (iph->nexthdr == NEXTHDR_ICMP) {
+ key.remote_ipv6[3] = _htonl(1);
+ } else {
+ if (iph->nexthdr != NEXTHDR_TCP) {
+ ERROR(iph->nexthdr);
+ return TC_ACT_SHOT;
+ }
+
+ if (tcp->dest == htons(5200)) {
+ key.remote_ipv6[3] = _htonl(1);
+ } else if (tcp->dest == htons(5201)) {
+ key.remote_ipv6[3] = _htonl(2);
+ } else {
+ ERROR(tcp->dest);
+ return TC_ACT_SHOT;
+ }
+ }
+
+ ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+ if (ret < 0) {
+ ERROR(ret);
+ return TC_ACT_SHOT;
+ }
+
+ return TC_ACT_OK;
+}
+
+SEC("ip6ip6_get_tunnel")
+int _ip6ip6_get_tunnel(struct __sk_buff *skb)
+{
+ int ret;
+ struct bpf_tunnel_key key;
+ char fmt[] = "remote ip6 %x::%x\n";
+
+ ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+ if (ret < 0) {
+ ERROR(ret);
+ return TC_ACT_SHOT;
+ }
+
+ bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
+ _htonl(key.remote_ipv6[3]));
+ return TC_ACT_OK;
+}
+
+
char _license[] SEC("license") = "GPL";
--- /dev/null
+#!/bin/bash
+
+function config_device {
+ ip netns add at_ns0
+ ip netns add at_ns1
+ ip netns add at_ns2
+ ip link add veth0 type veth peer name veth0b
+ ip link add veth1 type veth peer name veth1b
+ ip link add veth2 type veth peer name veth2b
+ ip link set veth0b up
+ ip link set veth1b up
+ ip link set veth2b up
+ ip link set dev veth0b mtu 1500
+ ip link set dev veth1b mtu 1500
+ ip link set dev veth2b mtu 1500
+ ip link set veth0 netns at_ns0
+ ip link set veth1 netns at_ns1
+ ip link set veth2 netns at_ns2
+ ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
+ ip netns exec at_ns0 ip addr add 2401:db00::1/64 dev veth0 nodad
+ ip netns exec at_ns0 ip link set dev veth0 up
+ ip netns exec at_ns1 ip addr add 172.16.1.101/24 dev veth1
+ ip netns exec at_ns1 ip addr add 2401:db00::2/64 dev veth1 nodad
+ ip netns exec at_ns1 ip link set dev veth1 up
+ ip netns exec at_ns2 ip addr add 172.16.1.200/24 dev veth2
+ ip netns exec at_ns2 ip addr add 2401:db00::3/64 dev veth2 nodad
+ ip netns exec at_ns2 ip link set dev veth2 up
+ ip link add br0 type bridge
+ ip link set br0 up
+ ip link set dev br0 mtu 1500
+ ip link set veth0b master br0
+ ip link set veth1b master br0
+ ip link set veth2b master br0
+}
+
+function add_ipip_tunnel {
+ ip netns exec at_ns0 \
+ ip link add dev $DEV_NS type ipip local 172.16.1.100 remote 172.16.1.200
+ ip netns exec at_ns0 ip link set dev $DEV_NS up
+ ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+ ip netns exec at_ns1 \
+ ip link add dev $DEV_NS type ipip local 172.16.1.101 remote 172.16.1.200
+ ip netns exec at_ns1 ip link set dev $DEV_NS up
+ # same inner IP address in at_ns0 and at_ns1
+ ip netns exec at_ns1 ip addr add dev $DEV_NS 10.1.1.100/24
+
+ ip netns exec at_ns2 ip link add dev $DEV type ipip external
+ ip netns exec at_ns2 ip link set dev $DEV up
+ ip netns exec at_ns2 ip addr add dev $DEV 10.1.1.200/24
+}
+
+function add_ipip6_tunnel {
+ ip netns exec at_ns0 \
+ ip link add dev $DEV_NS type ip6tnl mode ipip6 local 2401:db00::1/64 remote 2401:db00::3/64
+ ip netns exec at_ns0 ip link set dev $DEV_NS up
+ ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+ ip netns exec at_ns1 \
+ ip link add dev $DEV_NS type ip6tnl mode ipip6 local 2401:db00::2/64 remote 2401:db00::3/64
+ ip netns exec at_ns1 ip link set dev $DEV_NS up
+ # same inner IP address in at_ns0 and at_ns1
+ ip netns exec at_ns1 ip addr add dev $DEV_NS 10.1.1.100/24
+
+ ip netns exec at_ns2 ip link add dev $DEV type ip6tnl mode ipip6 external
+ ip netns exec at_ns2 ip link set dev $DEV up
+ ip netns exec at_ns2 ip addr add dev $DEV 10.1.1.200/24
+}
+
+function add_ip6ip6_tunnel {
+ ip netns exec at_ns0 \
+ ip link add dev $DEV_NS type ip6tnl mode ip6ip6 local 2401:db00::1/64 remote 2401:db00::3/64
+ ip netns exec at_ns0 ip link set dev $DEV_NS up
+ ip netns exec at_ns0 ip addr add dev $DEV_NS 2601:646::1/64
+ ip netns exec at_ns1 \
+ ip link add dev $DEV_NS type ip6tnl mode ip6ip6 local 2401:db00::2/64 remote 2401:db00::3/64
+ ip netns exec at_ns1 ip link set dev $DEV_NS up
+ # same inner IP address in at_ns0 and at_ns1
+ ip netns exec at_ns1 ip addr add dev $DEV_NS 2601:646::1/64
+
+ ip netns exec at_ns2 ip link add dev $DEV type ip6tnl mode ip6ip6 external
+ ip netns exec at_ns2 ip link set dev $DEV up
+ ip netns exec at_ns2 ip addr add dev $DEV 2601:646::2/64
+}
+
+function attach_bpf {
+ DEV=$1
+ SET_TUNNEL=$2
+ GET_TUNNEL=$3
+ ip netns exec at_ns2 tc qdisc add dev $DEV clsact
+ ip netns exec at_ns2 tc filter add dev $DEV egress bpf da obj tcbpf2_kern.o sec $SET_TUNNEL
+ ip netns exec at_ns2 tc filter add dev $DEV ingress bpf da obj tcbpf2_kern.o sec $GET_TUNNEL
+}
+
+function test_ipip {
+ DEV_NS=ipip_std
+ DEV=ipip_bpf
+ config_device
+# tcpdump -nei br0 &
+ cat /sys/kernel/debug/tracing/trace_pipe &
+
+ add_ipip_tunnel
+ attach_bpf $DEV ipip_set_tunnel ipip_get_tunnel
+
+ ip netns exec at_ns0 ping -c 1 10.1.1.200
+ ip netns exec at_ns2 ping -c 1 10.1.1.100
+ ip netns exec at_ns0 iperf -sD -p 5200 > /dev/null
+ ip netns exec at_ns1 iperf -sD -p 5201 > /dev/null
+ sleep 0.2
+ # tcp check _same_ IP over different tunnels
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5200
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5201
+ cleanup
+}
+
+# IPv4 over IPv6 tunnel
+function test_ipip6 {
+ DEV_NS=ipip_std
+ DEV=ipip_bpf
+ config_device
+# tcpdump -nei br0 &
+ cat /sys/kernel/debug/tracing/trace_pipe &
+
+ add_ipip6_tunnel
+ attach_bpf $DEV ipip6_set_tunnel ipip6_get_tunnel
+
+ ip netns exec at_ns0 ping -c 1 10.1.1.200
+ ip netns exec at_ns2 ping -c 1 10.1.1.100
+ ip netns exec at_ns0 iperf -sD -p 5200 > /dev/null
+ ip netns exec at_ns1 iperf -sD -p 5201 > /dev/null
+ sleep 0.2
+ # tcp check _same_ IP over different tunnels
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5200
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5201
+ cleanup
+}
+
+# IPv6 over IPv6 tunnel
+function test_ip6ip6 {
+ DEV_NS=ipip_std
+ DEV=ipip_bpf
+ config_device
+# tcpdump -nei br0 &
+ cat /sys/kernel/debug/tracing/trace_pipe &
+
+ add_ip6ip6_tunnel
+ attach_bpf $DEV ip6ip6_set_tunnel ip6ip6_get_tunnel
+
+ ip netns exec at_ns0 ping -6 -c 1 2601:646::2
+ ip netns exec at_ns2 ping -6 -c 1 2601:646::1
+ ip netns exec at_ns0 iperf -6sD -p 5200 > /dev/null
+ ip netns exec at_ns1 iperf -6sD -p 5201 > /dev/null
+ sleep 0.2
+ # tcp check _same_ IP over different tunnels
+ ip netns exec at_ns2 iperf -6c 2601:646::1 -n 5k -p 5200
+ ip netns exec at_ns2 iperf -6c 2601:646::1 -n 5k -p 5201
+ cleanup
+}
+
+function cleanup {
+ set +ex
+ pkill iperf
+ ip netns delete at_ns0
+ ip netns delete at_ns1
+ ip netns delete at_ns2
+ ip link del veth0
+ ip link del veth1
+ ip link del veth2
+ ip link del br0
+ pkill tcpdump
+ pkill cat
+ set -ex
+}
+
+cleanup
+echo "Testing IP tunnels..."
+test_ipip
+test_ipip6
+test_ip6ip6
+echo "*** PASS ***"