#!/bin/bash
# Connects 6 network namespaces through veths.
# Each NS may have different IPv6 global scope addresses :
#   NS1 ---- NS2 ---- NS3 ---- NS4 ---- NS5 ---- NS6
# fb00::1           fd00::1  fd00::2  fd00::3  fb00::6
#                   fc42::1           fd00::4
#
# All IPv6 packets going to fb00::/16 through NS2 will be encapsulated in a
# IPv6 header with a Segment Routing Header, with segments :
# 	fd00::1 -> fd00::2 -> fd00::3 -> fd00::4
#
# 3 fd00::/16 IPv6 addresses are binded to seg6local End.BPF actions :
# - fd00::1 : add a TLV, change the flags and apply a End.X action to fc42::1
# - fd00::2 : remove the TLV, change the flags, add a tag
# - fd00::3 : apply an End.T action to fd00::4, through routing table 117
#
# fd00::4 is a simple Segment Routing node decapsulating the inner IPv6 packet.
# Each End.BPF action will validate the operations applied on the SRH by the
# previous BPF program in the chain, otherwise the packet is dropped.
#
# An UDP datagram is sent from fb00::1 to fb00::6. The test succeeds if this
# datagram can be read on NS6 when binding to fb00::6.

# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4

msg="skip all tests:"
if [ $UID != 0 ]; then
	echo $msg please run this as root >&2
	exit $ksft_skip
fi

TMP_FILE="/tmp/selftest_lwt_seg6local.txt"

cleanup()
{
	if [ "$?" = "0" ]; then
		echo "selftests: test_lwt_seg6local [PASS]";
	else
		echo "selftests: test_lwt_seg6local [FAILED]";
	fi

	set +e
	ip netns del ns1 2> /dev/null
	ip netns del ns2 2> /dev/null
	ip netns del ns3 2> /dev/null
	ip netns del ns4 2> /dev/null
	ip netns del ns5 2> /dev/null
	ip netns del ns6 2> /dev/null
	rm -f $TMP_FILE
}

set -e

ip netns add ns1
ip netns add ns2
ip netns add ns3
ip netns add ns4
ip netns add ns5
ip netns add ns6

trap cleanup 0 2 3 6 9

ip link add veth1 type veth peer name veth2
ip link add veth3 type veth peer name veth4
ip link add veth5 type veth peer name veth6
ip link add veth7 type veth peer name veth8
ip link add veth9 type veth peer name veth10

ip link set veth1 netns ns1
ip link set veth2 netns ns2
ip link set veth3 netns ns2
ip link set veth4 netns ns3
ip link set veth5 netns ns3
ip link set veth6 netns ns4
ip link set veth7 netns ns4
ip link set veth8 netns ns5
ip link set veth9 netns ns5
ip link set veth10 netns ns6

ip netns exec ns1 ip link set dev veth1 up
ip netns exec ns2 ip link set dev veth2 up
ip netns exec ns2 ip link set dev veth3 up
ip netns exec ns3 ip link set dev veth4 up
ip netns exec ns3 ip link set dev veth5 up
ip netns exec ns4 ip link set dev veth6 up
ip netns exec ns4 ip link set dev veth7 up
ip netns exec ns5 ip link set dev veth8 up
ip netns exec ns5 ip link set dev veth9 up
ip netns exec ns6 ip link set dev veth10 up
ip netns exec ns6 ip link set dev lo up

# All link scope addresses and routes required between veths
ip netns exec ns1 ip -6 addr add fb00::12/16 dev veth1 scope link
ip netns exec ns1 ip -6 route add fb00::21 dev veth1 scope link
ip netns exec ns2 ip -6 addr add fb00::21/16 dev veth2 scope link
ip netns exec ns2 ip -6 addr add fb00::34/16 dev veth3 scope link
ip netns exec ns2 ip -6 route add fb00::43 dev veth3 scope link
ip netns exec ns3 ip -6 route add fb00::65 dev veth5 scope link
ip netns exec ns3 ip -6 addr add fb00::43/16 dev veth4 scope link
ip netns exec ns3 ip -6 addr add fb00::56/16 dev veth5 scope link
ip netns exec ns4 ip -6 addr add fb00::65/16 dev veth6 scope link
ip netns exec ns4 ip -6 addr add fb00::78/16 dev veth7 scope link
ip netns exec ns4 ip -6 route add fb00::87 dev veth7 scope link
ip netns exec ns5 ip -6 addr add fb00::87/16 dev veth8 scope link
ip netns exec ns5 ip -6 addr add fb00::910/16 dev veth9 scope link
ip netns exec ns5 ip -6 route add fb00::109 dev veth9 scope link
ip netns exec ns5 ip -6 route add fb00::109 table 117 dev veth9 scope link
ip netns exec ns6 ip -6 addr add fb00::109/16 dev veth10 scope link

ip netns exec ns1 ip -6 addr add fb00::1/16 dev lo
ip netns exec ns1 ip -6 route add fb00::6 dev veth1 via fb00::21

ip netns exec ns2 ip -6 route add fb00::6 encap bpf in obj test_lwt_seg6local.o sec encap_srh dev veth2
ip netns exec ns2 ip -6 route add fd00::1 dev veth3 via fb00::43 scope link

ip netns exec ns3 ip -6 route add fc42::1 dev veth5 via fb00::65
ip netns exec ns3 ip -6 route add fd00::1 encap seg6local action End.BPF endpoint obj test_lwt_seg6local.o sec add_egr_x dev veth4

ip netns exec ns4 ip -6 route add fd00::2 encap seg6local action End.BPF endpoint obj test_lwt_seg6local.o sec pop_egr dev veth6
ip netns exec ns4 ip -6 addr add fc42::1 dev lo
ip netns exec ns4 ip -6 route add fd00::3 dev veth7 via fb00::87

ip netns exec ns5 ip -6 route add fd00::4 table 117 dev veth9 via fb00::109
ip netns exec ns5 ip -6 route add fd00::3 encap seg6local action End.BPF endpoint obj test_lwt_seg6local.o sec inspect_t dev veth8

ip netns exec ns6 ip -6 addr add fb00::6/16 dev lo
ip netns exec ns6 ip -6 addr add fd00::4/16 dev lo

ip netns exec ns1 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
ip netns exec ns2 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
ip netns exec ns3 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
ip netns exec ns4 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
ip netns exec ns5 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null

ip netns exec ns6 sysctl net.ipv6.conf.all.seg6_enabled=1 > /dev/null
ip netns exec ns6 sysctl net.ipv6.conf.lo.seg6_enabled=1 > /dev/null
ip netns exec ns6 sysctl net.ipv6.conf.veth10.seg6_enabled=1 > /dev/null

ip netns exec ns6 nc -l -6 -u -d 7330 > $TMP_FILE &
ip netns exec ns1 bash -c "echo 'foobar' | nc -w0 -6 -u -p 2121 -s fb00::1 fb00::6 7330"
sleep 5 # wait enough time to ensure the UDP datagram arrived to the last segment
kill -INT $!

if [[ $(< $TMP_FILE) != "foobar" ]]; then
	exit 1
fi

exit 0