kola/tests/misc: add test to verify the DHCP propagation of NTP servers

Writing this test to verify coreos/fedora-coreos-config#412
to enable the DHCP propagation of NTP servers. We don't need this test once the
upstream/downstream patch merges.
upstream patch: https://listengine.tuxfamily.org/chrony.tuxfamily.org/chrony-dev/2020/05/msg00023.html
downstream patch: https://src.fedoraproject.org/rpms/chrony/pull-request/3

mantle/kola/tests/misc/chronydhcp.go

@@ -0,0 +1,119 @@
+// Copyright 2020 Red Hat
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package misc
+
+import (
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/coreos/mantle/kola"
+	"github.com/coreos/mantle/kola/cluster"
+	"github.com/coreos/mantle/kola/register"
+	"github.com/coreos/mantle/platform/conf"
+	"github.com/coreos/mantle/util"
+	"github.com/vincent-petithory/dataurl"
+)
+
+var script = []byte(`#!/bin/bash
+# This script creates two veth interfaces i.e. one for the host machine 
+# and other for the container(dnsmasq server). This setup will be helpful
+# to verify the DHCP propagation of NTP servers
+# https://github.com/coreos/fedora-coreos-config/pull/412
+
+# This is needed to run a container with systemd
+setsebool container_manage_cgroup 1
+
+# create a network namespace
+ip netns add container
+
+# create veth pair and assign a namespace to veth-container
+ip link add veth-host type veth peer name veth-container
+ip link set veth-container netns container
+
+# assign an IP address to the 'veth-container' interface and bring it up
+ip netns exec container ip address add 172.16.0.1/24 dev veth-container
+ip netns exec container ip link set veth-container up
+
+# run podman commands to set up dnsmasq server
+cd /tmp
+cat <<EOF >Dockerfile
+FROM registry.fedoraproject.org/fedora:32
+RUN dnf -y install systemd dnsmasq iproute iputils
+RUN dnf clean all
+RUN systemctl enable dnsmasq
+CMD [ "/sbin/init" ]
+EOF
+podman build -t dnsmasq .
+podman run -d --rm --name dnsmasq --privileged --network ns:/var/run/netns/container dnsmasq
+podman exec -it dnsmasq /bin/bash -c "echo -e 'dhcp-range=172.16.0.10,172.16.0.20,12h\nbind-interfaces\ninterface=veth-container\ndhcp-option=option:ntp-server,129.6.15.30' >> /etc/dnsmasq.d/dhcp; sudo systemctl restart dnsmasq.service"
+
+# create a static ethernet connection for the 'veth-host'
+nmcli dev set veth-host managed yes
+ip link set veth-host up`)
+
+func init() {
+	register.RegisterTest(&register.Test{
+		Name:        "coreos.chrony.dhcp.verify",
+		Run:         verifyDHCPPropagationOfNTPServers,
+		ClusterSize: 1,
+		Tags:        []string{"chrony", "dhcp", "ntp", kola.NeedsInternetTag},
+		UserDataV3: conf.Ignition(fmt.Sprintf(`{
+			"ignition": {"version": "3.0.0"},
+			"storage": {
+				"files": [
+				  {
+					"group": {},
+					"path": "/usr/local/bin/setup.sh",
+					"user": {},
+					"contents": {
+					  "source": %q,
+					  "verification": {}
+					},
+					"mode": 493
+				  }
+				]
+			  },
+			  "systemd": {
+				"units": [
+				  {
+					"contents": "[Unit]\nDescription=verify chrony using NTP settings from DHCP\n[Service]\nType=oneshot\nExecStart=/usr/local/bin/setup.sh\nRestart=on-failure\nRemainAfterExit=yes\n[Install]\nWantedBy=multi-user.target\n",
+					"name": "chrony-dhcp.service"
+				  }
+				]
+			  }
+			}`, dataurl.EncodeBytes(script))),
+	})
+}
+
+func verifyDHCPPropagationOfNTPServers(c cluster.TestCluster) {
+	m := c.Machines()[0]
+	// Wait a little bit for the chrony-dhcp.service to start
+	if err := util.WaitUntilReady(10*time.Minute, 5*time.Second, func() (bool, error) {
+		_, _, err := m.SSH("sudo systemctl start chrony-dhcp.service")
+		if err != nil {
+			return false, err
+		}
+		return true, nil
+	}); err != nil {
+		c.Fatal("failed to start chrony-dhcp.service: %v", err)
+	}
+
+	out := c.MustSSH(m, "chronyc sources")
+	// Name: time-c-g.nist.gov  IP address: 129.6.15.30
+	if !strings.Contains(string(out), "time-c-g.nist.gov") {
+		c.Fatalf("propagation of ntp server information via dhcp failed)
+	}
+}