KubeArmor and Cilium on Debian 10 (Buster)

Overview¶

This user journey guides you to install and verify the compatibility of Kuberarmor and Cilium on Debian 10 (Buster) with 4.19 Kernel Version by applying policies on kubernetes workloads.

Step 1: Install etcd in control plane VM¶

Install etcd using below command:

sudo apt-get install etcd

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Once etcd is installed, configure the following values in /etc/default/etcd as shown below.

ETCD_LISTEN_CLIENT_URLS=http://0.0.0.0:2379
ETCD_ADVERTISE_CLIENT_URLS=http://0.0.0.0:2379

Restart etcd & check the etcd status:

sudo service etcd restart

sudo service etcd status

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Step 2: Install KVM-Service in control plane¶

Download the latest deb Package

wget https://github.com/kubearmor/kvm-service/releases/download/0.1/kvmservice_0.1_linux-amd64.deb

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dpkg -i kvmservice_0.1_linux-amd64.deb

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systemctl status kvmservice

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Step 3: Install Karmor in control plane¶

curl -sfL https://raw.githubusercontent.com/kubearmor/kubearmor-client/main/install.sh | sudo sh -s -- -b /usr/local/bin

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Step 4: Onboard VMs using Karmor¶

cat kvmpolicy1.yaml

apiVersion: security.kubearmor.com/v1
kind: KubeArmorVirtualMachine
metadata:
  name: testvm1
  labels:
    name: vm1
    vm: true

Run this command to add the VM:

karmor vm add kvmpolicy1.yaml

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To see the onboarded VM’s

karmor vm list

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Step 5: Generate installation scripts for configured worker VMs¶

Generate VM installation scripts for the configured VM by running the following command:

karmor vm --kvms getscript -v testvm1

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Step 6: Execute the installation script in VMs¶

Note: Docker needs to install before running the script.

Install pre-requisites:

Repositories: /etc/apt/sources.list should include the non-free repository and look something like this:

vi /etc/apt/sources.list

Add the following:

deb http://deb.debian.org/debian sid main contrib non-free

deb-src http://deb.debian.org/debian sid main contrib non-free

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Install build dependencies:

apt-get update

According to

sudo apt-get install arping bison clang-format cmake dh-python \
    dpkg-dev pkg-kde-tools ethtool flex inetutils-ping iperf \
    libbpf-dev libclang-dev libclang-cpp-dev libedit-dev libelf-dev \
    libfl-dev libzip-dev linux-libc-dev llvm-dev libluajit-5.1-dev \
    luajit python3-netaddr python3-pyroute2 python3-distutils python3

Install & compile BCC:

git clone https://github.com/iovisor/bcc.git

mkdir bcc/build; cd bcc/build

cmake ..

make

sudo make install

Install linux-headers:

sudo apt install linux-headers-$(uname -r)

If you getting the following error,

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Follow this steps to slove the error:

apt install gcc-8

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sudo apt install linux-headers-$(uname -r)

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Comment the following line on the script and save it:

vi testvm1.sh

#sudo docker run --name kubearmor $DOCKER_OPTS $KUBEARMOR_IMAGE $KUBEARMOR_OPTS

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Execute the installation script:

Copy the generated installation scripts to appropriate VMs using scp or rsync method and execute the scripts to run Cilium.

The script downloads Cilium Docker images and run them as containers in each VM. Cilium running in each VM connects to the KVM-Service control plane to register themselves and receive information about other VMs in the cluster, labels, IPs and configured security policies.

Execute the script on worker VM by running the following command:

./testvm1.sh

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Note: Make sure the kvm-service is running on control plane VM & To onboard more worker VM repeat Step 4, Step 5 & Step 6.

You can verify by running following command:

sudo docker ps

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Step 7: Install Kubearmor on worker VMs¶

Download the latest release of KubeArmor

wget https://github.com/kubearmor/KubeArmor/releases/download/v0.3.1/kubearmor_0.3.1_linux-amd64.deb

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dpkg -i kubearmor_0.3.1_linux-amd64.deb

Note: While installing if you get the following error,

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Run the following command to fix the error:

apt --fix-broken install

dpkg -i kubearmor_0.3.1_linux-amd64.deb

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Start & check the status of Kubearmor:

sudo systemctl start kubearmor

sudo systemctl enable kubearmor

sudo systemctl status kubearmor

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Step 8: Apply and Verify Kubearmor system policy¶

cat khp-example-vmname.yaml

apiVersion: security.kubearmor.com/v1
kind: KubeArmorHostPolicy
metadata:
  name: hsp-kubearmor-dev-proc-path-block
spec:
  process:
    matchPaths:
    - path: /usr/bin/sleep # try sleep 1
  action:
    Block

Run this command to apply the policy:

karmor vm policy add khp-example-vmname.yaml

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Step 9: Policy Violation¶

sleep 10

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Verifying Policy Violation Logs:

karmor log

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Step 10: Apply and Verify Cilium network policy¶

1. Allow connectivity with the control plane ( and port 2379)

cat vm-allow-control-plane.yaml

kind: CiliumNetworkPolicy
metadata:
  name: "vm-allow-control-plane"
spec:
  description: "Policy to allow traffic to kv-store"
  nodeSelector:
    matchLabels:
      name: vm1
  egress:
  - toCIDR:
    - 10.138.0.5/32
    toPorts:
    - ports:
      - port: "2379"
        protocol: TCP

2. For SSH connectivity allow port 22 and 169.254.169.254 port 80

cat vm-allow-ssh.yaml

kind: CiliumNetworkPolicy
metadata:
  name: "vm-allow-ssh"
spec:
  description: "Policy to allow SSH"
  nodeSelector:
    matchLabels:
      name: vm1
  egress:
  - toPorts:
    - ports:
      - port: "22"
        protocol: TCP
  - toCIDR:
    - 169.254.169.254/32
    toPorts:
    - ports:
      - port: "80"
        protocol: TCP

3. This policy block the DNS access in VM

cat vm-dns-visibility.yaml

kind: CiliumNetworkPolicy
metadata:
  name: "vm-dns-visibility"
spec:
  description: "Policy to enable DNS visibility"
  nodeSelector:
    matchLabels:
      name: vm1
  egress:
  - toPorts:
    - ports:
      - port: "53"
        protocol: ANY
      rules:
        dns:
        - matchPattern: "*"

4. This policy allow access of “www.google.co.in” alone in VM

cat vm-allow-www-google-co-in.yaml

kind: CiliumNetworkPolicy
metadata:
  name: "vm-allow-www.google.co.in"
spec:
  description: "Policy to allow traffic to www.google.co.in"
  nodeSelector:
    matchLabels:
      name: vm1
  egress:
  - toFQDNs:
    - matchName: www.google.co.in
    toPorts:
    - ports:
      - port: "80"
        protocol: TCP
      - port: "443"
        protocol: TCP

Run this command to apply the policy:

karmor vm --kvms policy add vm-allow-control-plane.yaml

karmor vm --kvms policy add vm-allow-ssh.yaml

karmor vm --kvms policy add vm-dns-visibility.yaml

karmor vm --kvms policy add vm-allow-www-google-co-in.yaml

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Step 11: Policy Violation on worker node¶

curl http://www.google.co.in/

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curl https://go.dev/

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Verifying Policy Violation Logs:

docker exec -it cilium hubble observe -f -t policy-verdict

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