ttcn3-epdg: Test GTP-U userplane

Set the assigned IP address for the UE in the EPDG docker container on
the eth0 interface. This way the emulated UPF (ttcn3) can test
decaps+encaps of osmo-epdg tun by pinging the UE IP address and
expecting a pong back.

I'm already seeing the UDP/GTPU/ICMP(echoReq) arriving at the osmo-epdg
gtp tundev:
"""
[29343.392749] gtp0: GTPv1-U: new PDP ctx id=ad84246b/adb4568b ssgn=172.18.186.103 ms=192.168.0.2 (pdp=0000000066dc66dd)
[29343.397738] gtp0: encap_recv sk=00000000382e4a54
[29343.397744] gtp0: received GTP1U packet
[29343.397746] gtp0: forwarding packet from GGSN to uplink
"""

TODO: What's missing here is to set a route back to gtp0 for the pong.

Change-Id: Icc5710b42e5a5374aade6b952e1c543565ffad2e

osmo-epdg-master/Dockerfile

@@ -4,6 +4,14 @@ FROM	$USER/$DISTRO-erlang
 # Arguments used after FROM must be specified again
 ARG	DISTRO
 
+# $distro-erlang switched to user build, but we need to install more stuff beforehand:
+USER	root
+RUN	apt-get update && \
+	apt-get install -y --no-install-recommends \
+		iproute2 && \
+	apt-get clean
+USER	build
+
 WORKDIR	/tmp
 
 ARG	OSMO_EPDG_BRANCH="master"

ttcn3-epdg-test/epdg.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+set +e
+set -x
+
+ip addr add 192.168.0.2 dev eth0
+ERL_FLAGS='-config /data/osmo-epdg.config' /tmp/osmo-epdg/_build/default/bin/osmo-epdg

ttcn3-epdg-test/jenkins.sh

@@ -15,6 +15,7 @@ write_mp_osmo_repo "$VOL_BASE_DIR/epdg-tester/EPDG_Tests.cfg"
 
 mkdir $VOL_BASE_DIR/epdg
 cp osmo-epdg.config $VOL_BASE_DIR/epdg/
+cp epdg.sh $VOL_BASE_DIR/epdg/
 
 network_create
 network_replace_subnet_in_configs
@@ -32,7 +33,8 @@ docker run	--rm \
 		-v $VOL_BASE_DIR/epdg:/data \
 		--name ${BUILD_TAG}-epdg -d \
 		$DOCKER_ARGS \
-		$REPO_USER/osmo-epdg-$IMAGE_SUFFIX
+		$REPO_USER/osmo-epdg-$IMAGE_SUFFIX \
+		/bin/sh -c "/data/epdg.sh >/data/osmo-epdg.log 2>&1"
 
 # Give some time to osmo-epdg to be fully started; it's a bit slow...
 sleep 2