Commit ac6e45e0 authored by Christian Ehrig's avatar Christian Ehrig Committed by Daniel Borkmann
Browse files

selftests/bpf: Add BPF_F_NO_TUNNEL_KEY test 



This patch adds a selftest simulating a GRE sender and receiver using
tunnel headers without tunnel keys. It validates if packets encapsulated
using BPF_F_NO_TUNNEL_KEY are decapsulated by a GRE receiver not
configured with tunnel keys.

Signed-off-by: default avatarChristian Ehrig <cehrig@cloudflare.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarJakub Sitnicki <jakub@cloudflare.com>
Acked-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221218051734.31411-2-cehrig@cloudflare.com
parent e26aa600

tools/testing/selftests/bpf/progs/test_tunnel_kern.c

+21 −0
Original line number Diff line number Diff line
@@ -81,6 +81,27 @@ int gre_set_tunnel(struct __sk_buff *skb) 
	return TC_ACT_OK;

}



SEC("tc")

int gre_set_tunnel_no_key(struct __sk_buff *skb)

{

	int ret;

	struct bpf_tunnel_key key;



	__builtin_memset(&key, 0x0, sizeof(key));

	key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */

	key.tunnel_ttl = 64;



	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),

				     BPF_F_ZERO_CSUM_TX | BPF_F_SEQ_NUMBER |

				     BPF_F_NO_TUNNEL_KEY);

	if (ret < 0) {

		log_err(ret);

		return TC_ACT_SHOT;

	}



	return TC_ACT_OK;

}



SEC("tc")

int gre_get_tunnel(struct __sk_buff *skb)

{

tools/testing/selftests/bpf/test_tunnel.sh

+37 −3
Original line number Diff line number Diff line
@@ -66,15 +66,20 @@ config_device() 


add_gre_tunnel()

{

	tun_key=

	if [ -n "$1" ]; then

		tun_key="key $1"

	fi



	# at_ns0 namespace

	ip netns exec at_ns0 \

        ip link add dev $DEV_NS type $TYPE seq key 2 \

        ip link add dev $DEV_NS type $TYPE seq $tun_key \

		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



	# root namespace

	ip link add dev $DEV type $TYPE key 2 external

	ip link add dev $DEV type $TYPE $tun_key external

	ip link set dev $DEV up

	ip addr add dev $DEV 10.1.1.200/24

}
@@ -238,7 +243,7 @@ test_gre() 


	check $TYPE

	config_device

	add_gre_tunnel

	add_gre_tunnel 2

	attach_bpf $DEV gre_set_tunnel gre_get_tunnel

	ping $PING_ARG 10.1.1.100

	check_err $?
@@ -253,6 +258,30 @@ test_gre() 
        echo -e ${GREEN}"PASS: $TYPE"${NC}

}



test_gre_no_tunnel_key()

{

	TYPE=gre

	DEV_NS=gre00

	DEV=gre11

	ret=0



	check $TYPE

	config_device

	add_gre_tunnel

	attach_bpf $DEV gre_set_tunnel_no_key gre_get_tunnel

	ping $PING_ARG 10.1.1.100

	check_err $?

	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200

	check_err $?

	cleanup



        if [ $ret -ne 0 ]; then

                echo -e ${RED}"FAIL: $TYPE"${NC}

                return 1

        fi

        echo -e ${GREEN}"PASS: $TYPE"${NC}

}



test_ip6gre()

{

	TYPE=ip6gre
@@ -589,6 +618,7 @@ cleanup() 
	ip link del ipip6tnl11 2> /dev/null

	ip link del ip6ip6tnl11 2> /dev/null

	ip link del gretap11 2> /dev/null

	ip link del gre11 2> /dev/null

	ip link del ip6gre11 2> /dev/null

	ip link del ip6gretap11 2> /dev/null

	ip link del geneve11 2> /dev/null
@@ -641,6 +671,10 @@ bpf_tunnel_test() 
	test_gre

	errors=$(( $errors + $? ))



	echo "Testing GRE tunnel (without tunnel keys)..."

	test_gre_no_tunnel_key

	errors=$(( $errors + $? ))



	echo "Testing IP6GRE tunnel..."

	test_ip6gre

	errors=$(( $errors + $? ))