docs: ikev2 usecases

Type: docs

Change-Id: Ib607b9426572585c1c7bfc4fcbbb1591ff5d9d42
Signed-off-by: Filip Tehlar <ftehlar@cisco.com>

1 files changed, 197 insertions, 0 deletions

diff --git a/docs/usecases/vpp_resp_sswan_init.md b/docs/usecases/vpp_resp_sswan_init.md
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+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
+```