VPP as IKEv2 responder and strongSwan as initiator
==================================================
Prerequisites
-------------
To make the examples easier to configure ``docker`` it is required to
pull strongSwan docker image. The networking is done using Linux’ veth
interfaces and namespaces.
Setup
-----
First a topology:
::
192.168.3.2 192.168.5.2
+ loopback
| +
+----+----+ 192.168.10.2 +-----+----+
| VPP | |initiator |
|responder+----------------------+strongSwan|
+---------+ +----------+
192.168.10.1
Create veth interfaces and namespaces and configure them:
::
sudo ip link add gw type veth peer name swanif
sudo ip link set dev gw up
sudo ip netns add ns
sudo ip link add veth_priv type veth peer name priv
sudo ip link set dev priv up
sudo ip link set dev veth_priv up netns ns
sudo ip netns exec ns \
bash -c "
ip link set dev lo up
ip addr add 192.168.3.2/24 dev veth_priv
ip route add 192.168.5.0/24 via 192.168.3.1"
Create directory with strongswan configs that will be mounted to the
docker container
::
mkdir /tmp/sswan
Create the ``ipsec.conf`` file in the ``/tmp/sswan`` directory with
following content:
::
config setup
strictcrlpolicy=no
conn initiator
mobike=no
auto=add
type=tunnel
keyexchange=ikev2
ike=aes256gcm16-prfsha256-modp2048!
esp=aes256gcm16-esn!
# local:
leftauth=psk
leftid=@roadwarrior.vpn.example.com
leftsubnet=192.168.5.0/24
# remote: (vpp gateway)
rightid=@vpp.home
right=192.168.10.2
rightauth=psk
rightsubnet=192.168.3.0/24
``/tmp/sswan/ipsec.secrets``
::
: PSK 'Vpp123'
``/tmp/sswan/strongswan.conf``
::
charon {
load_modular = yes
plugins {
include strongswan.d/charon/*.conf
}
filelog {
/tmp/charon.log {
time_format = %b %e %T
ike_name = yes
append = no
default = 2
flush_line = yes
}
}
}
include strongswan.d/*.conf
Start docker container with strongSwan:
::
docker run --name sswan -d --privileged --rm --net=none \
-v /tmp/sswan:/conf -v /tmp/sswan:/etc/ipsec.d philplckthun/strongswan
Finish configuration of initiator’s private network:
::
pid=$(docker inspect --format "{{.State.Pid}}" sswan)
sudo ip link set netns $pid dev swanif
sudo nsenter -t $pid -n ip addr add 192.168.10.1/24 dev swanif
sudo nsenter -t $pid -n ip link set dev swanif up
sudo nsenter -t $pid -n ip addr add 192.168.5.2/32 dev lo
sudo nsenter -t $pid -n ip link set dev lo up
Start VPP …
::
sudo /usr/bin/vpp unix { \
cli-listen /tmp/vpp.sock \
gid $(id -g) } \
api-segment { prefix vpp } \
plugins { plugin dpdk_plugin.so { disable } }
… and configure it:
::
create host-interface name gw
set interface ip addr host-gw 192.168.10.2/24
set interface state host-gw up
create host-interface name priv
set interface ip addr host-priv 192.168.3.1/24
set interface state host-priv up
ikev2 profile add pr1
ikev2 profile set pr1 auth shared-key-mic string Vpp123
ikev2 profile set pr1 id local fqdn vpp.home
ikev2 profile set pr1 id remote fqdn roadwarrior.vpn.example.com
ikev2 profile set pr1 traffic-selector local ip-range 192.168.3.0 - 192.168.3.255 port-range 0 - 65535 protocol 0
ikev2 profile set pr1 traffic-selector remote ip-range 192.168.5.0 - 192.168.5.255 port-range 0 - 65535 protocol 0
create ipip tunnel src 192.168.10.2 dst 192.168.10.1
ikev2 profile set pr1 tunnel ipip0
ip route add 192.168.5.0/24 via 192.168.10.1 ipip0
set interface unnumbered ipip0 use host-gw
Initiate the IKEv2 connection:
::
$ sudo docker exec sswan ipsec up initiator
...
CHILD_SA initiator{1} established with SPIs c320c95f_i 213932c2_o and TS 192.168.5.0/24 === 192.168.3.0/24
connection 'initiator' established successfully
::
vpp# show ikev2 sa details
iip 192.168.10.1 ispi 7849021d9f655f1b rip 192.168.10.2 rspi 5a9ca7469a035205
encr:aes-gcm-16 prf:hmac-sha2-256 dh-group:modp-2048
nonce i:692ce8fd8f1c1934f63bfa2b167c4de2cff25640dffe938cdfe01a5d7f6820e6
r:3ed84a14ea8526063e5aa762312be225d33e866d7152b9ce23e50f0ededca9e3
SK_d 9a9b896ed6c35c78134fcd6e966c04868b6ecacf6d5088b4b2aee8b05d30fdda
SK_e i:00000000: 1b1619788d8c812ca5916c07e635bda860f15293099f3bf43e8d88e52074b006
00000020: 72c8e3e3
r:00000000: 89165ceb2cef6a6b3319f437386292d9ef2e96d8bdb21eeb0cb0d3b92733de03
00000020: bbc29c50
SK_p i:fe35fca30985ee75e7c8bc0d7bc04db7a0e1655e997c0f5974c31458826b6fef
r:0dd318662a96a25fcdf4998d8c6e4180c67c03586cf91dab26ed43aeda250272
identifier (i) id-type fqdn data roadwarrior.vpn.example.com
identifier (r) id-type fqdn data vpp.home
child sa 0:encr:aes-gcm-16 esn:yes
spi(i) c320c95f spi(r) 213932c2
SK_e i:2a6c9eae9dbed202c0ae6ccc001621aba5bb0b01623d4de4d14fd27bd5185435
r:15e2913d39f809040ca40a02efd27da298b6de05f67bd8f10210da5e6ae606fb
traffic selectors (i):0 type 7 protocol_id 0 addr 192.168.5.0 - 192.168.5.255 port 0 - 65535
traffic selectors (r):0 type 7 protocol_id 0 addr 192.168.3.0 - 192.168.3.255 port 0 - 65535
Now we can generate some traffic between responder’s and initiator’s
private networks and see it works.
::
$ sudo ip netns exec ns ping 192.168.5.2
PING 192.168.5.2 (192.168.5.2) 56(84) bytes of data.
64 bytes from 192.168.5.2: icmp_seq=1 ttl=63 time=1.02 ms
64 bytes from 192.168.5.2: icmp_seq=2 ttl=63 time=0.599 ms