initial

Author: bgeesaman

Dockerfile

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+FROM ruby:2.7.2-alpine3.13
+
+ARG K8S_VERSION=1.18.8
+ENV K8S_VERSION=${K8S_VERSION}
+
+# Install tools and etcd and get the api-server binary
+RUN apk add --no-cache --update -X http://dl-cdn.alpinelinux.org/alpine/edge/testing \
+    bash tar git curl jq etcd etcd-ctl etcd-openrc openrc less && \
+    gem install pry && \
+    curl -Lo kube-apiserver https://dl.k8s.io/release/v${K8S_VERSION}/bin/linux/amd64/kube-apiserver && \
+    chmod +x ./kube-apiserver && \
+    mv ./kube-apiserver /usr/local/bin && \
+    rm -rf /tmp/* && \
+    rm -rf /var/cache/apk/* && \
+    rm -rf /var/tmp/*
+
+# Copy in startup script, k8s token file for auth, and the auger binary
+ADD support/launch.sh /
+ADD support/tokens.txt /
+ADD support/load.rb /
+
+# Make exec
+RUN chmod +x /launch.sh /load.rb
+# Necessary for the auger binary to run
+RUN mkdir /lib64 && ln -s /lib/libc.musl-x86_64.so.1 /lib64/ld-linux-x86-64.so.2
+
+EXPOSE 31337
+CMD ["/bin/bash", "-c", "/launch.sh"]

LICENSE

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+Copyright 2021 Darkbit.io
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Makefile

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+SHELL := /usr/bin/env bash
+
+IMAGENAME=k8s-mirror
+IMAGEREPO=darkbitio/$(IMAGENAME)
+IMAGEPATH=$(IMAGEREPO):latest
+
+NDEF = $(if $(value $(1)),,$(error $(1) not set))
+
+DOCKERBUILD=docker build -t $(IMAGEREPO):latest .
+
+COMMAND=docker run --rm -it -p31337:8080 -v "$(PWD)/data":/data
+
+.PHONY: build run shell
+build:
+	@echo "Building $(IMAGEREPO):latest"
+	@$(DOCKERBUILD)
+
+run:
+	@echo "Running in $(IMAGEREPO):latest"
+	@$(COMMAND) $(IMAGEPATH) || exit 0
+
+shell:
+	@echo "Running a shell inside the container"
+	@$(COMMAND) $(IMAGEPATH) /bin/bash || exit 0

README.md

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+# K8s-mirror
+
+## Why?
+
+To enable high-fidelity, offline review of Kubernetes clusters as a part of Darkbit's cloud and Kubernetes security [consulting services offerings](https://darkbit.io/services/), a simple script to export all K8s resources from a cluster was developed.  A modified version of this script is included in this repository as `kube-exporter.sh`.
+
+The original goal of this export format was to support ingestion by the [OpenCSPM](https://github.com/opencspm/opencspm) analysis platform.  However, there are instances where analysis is best performed with a quick run of `kubectl`.  Without having direct access to a client's cluster, a "mirror" cluster is needed.
+
+## How?
+
+* Clone the repository
+* Run `kube-exporter.sh` against the target cluster.  It's output file should be named `<kubecontext_name>.json`.
+* Copy `<kubecontext_name>.json` to `data/import.json`
+* Modify the `Dockerfile` to use the correct `K8S_VERSION`
+* Run `make build` to build the docker container.
+* Run `make run` to launch the "mirror" cluster container.  This container runs etcd, loads the data from `/data/import.json` into etcd, and then launches an _insecure_ API server.  That is, it runs without TLS, listens on `localhost:31337` and requires a simple token for authentication as `cluster-admin`.
+* Run `export KUBECONFIG=kubeconfig.honk`
+* Run `kubectl get pods -A` to query for pods in the "mirror" cluster container.
+* When done, kill the container to clean up.
+
+## Warning!
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

data/.gitkeep

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+#!/usr/bin/env bash
+
+set -eo pipefail
+
+command -v kubectl >/dev/null 2>&1 || { \
+ echo >&2 "kubectl is needed, but it's not installed.  Aborting."
+ echo >&2 "Refer to: https://kubernetes.io/docs/tasks/tools/install-kubectl/"
+ exit 1
+}
+command -v jq >/dev/null 2>&1 || { \
+ echo >&2 "jq is needed, but it's not installed.  Aborting."
+ echo >&2 "Refer to: https://stedolan.github.io/jq/"
+ exit 1
+}
+
+# Exports all resources from a K8s cluster
+# while redacting secrets values and env vars
+# Uses the current context
+
+CONTEXT="$(kubectl config current-context | sed -e 's/\//_/g' | sed -e 's/:/_/g')"
+OUTPUTFILE="${CONTEXT}.json"
+touch "${OUTPUTFILE}"
+cat /dev/null > "${OUTPUTFILE}"
+
+# API Resources
+APIRESOURCES="$(kubectl api-resources -o name --verbs list | sort -u)"
+REDACTEDRESOURCES='^(secrets|managedcertificate.+)$'
+for res in $APIRESOURCES; do
+  if [[ $res =~ $REDACTEDRESOURCES ]]; then
+    # redact secrets data values
+    kubectl get $res --all-namespaces --chunk-size=50 -ojson | jq -rc --arg CONTEXT "$CONTEXT" '.items[] | walk(if type=="object" and has("kubectl.kubernetes.io/last-applied-configuration") then ."kubectl.kubernetes.io/last-applied-configuration"="REDACTED" else . end) | walk(if type == "object" and has("data") then .data[] = "REDACTED" else . end) | {asset_type: ("k8s.io/"+ .kind), name: ("//"+ $CONTEXT + .metadata.selfLink), resource: {version: "v1", discovery_document_uri: "https://raw.githubusercontent.com/kubernetes/kubernetes/master/api/openapi-spec/swagger.json", data: .}}' >> "${OUTPUTFILE}"
+  else
+    # redact anywhere env vars have "value"
+    kubectl get $res --all-namespaces --chunk-size=50 -ojson | jq -rc --arg CONTEXT "$CONTEXT" '.items[] | walk(if type=="object" and has("kubectl.kubernetes.io/last-applied-configuration") then ."kubectl.kubernetes.io/last-applied-configuration"="REDACTED" else . end) | walk(if type=="object" and has("env") and (.env|type=="array") then walk(if type=="object" and has("name") and has("value") then .value="REDACTED" else . end) else . end) | {asset_type: ("k8s.io/"+ .kind), name: ("//"+ $CONTEXT + .metadata.selfLink), resource: {version: "v1", discovery_document_uri: "https://raw.githubusercontent.com/kubernetes/kubernetes/master/api/openapi-spec/swagger.json", data: .}}' >> "${OUTPUTFILE}"
+  fi
+done
+
+# Server version
+kubectl version -o json | jq -r '.serverVersion'| jq -rc --arg CONTEXT "$CONTEXT" '{asset_type: ("k8s.io/Version"), name: ("//"+ $CONTEXT + .metadata.selfLink), resource: {version: "v1", discovery_document_uri: "https://raw.githubusercontent.com/kubernetes/kubernetes/master/api/openapi-spec/swagger.json", data: .}}' >> "${OUTPUTFILE}"

kube-exporter.sh

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+apiVersion: v1
+kind: Config
+current-context: mirror
+clusters:
+- cluster:
+    server: http://localhost:31337
+  name: mirror
+users:
+- name: honk
+  user:
+    token: honk
+contexts:
+- context:
+    cluster: mirror
+    user: honk
+  name: mirror

kubeconfig.honk

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+#!/bin/bash
+
+rc-status
+touch /run/openrc/softlevel
+rc-service etcd start
+/load.rb /data/import.json
+kube-apiserver --etcd-servers http://127.0.0.1:2379 --insecure-bind-address=0.0.0.0 --insecure-port=8080 --allow-privileged=true --authorization-mode=Node,RBAC --anonymous-auth=false --token-auth-file=/tokens.txt -v=0 --storage-media-type=application/json

support/launch.sh

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+#!/usr/bin/env ruby
+
+require 'json'
+require 'yaml'
+require 'pry'
+
+def run_insert(input, insert_path)
+  result = IO.popen("etcdctl put #{insert_path}", 'r+') do |io|
+    io.write(input)
+    io.close_write
+    io.read
+  end
+  result
+end
+
+def parse_line(line)
+  json = JSON.parse(line)
+  namespace_name = json.dig('resource','data','metadata','namespace') || "unknown"
+  resource_name = json.dig('resource','data','metadata','name') || "unknown"
+  resource = json.dig('resource','data').to_json
+
+  case json.dig('asset_type')
+  when "k8s.io/Node"
+    run_insert(resource, "/registry/minions/#{resource_name}")
+  when "k8s.io/Pod"
+    run_insert(resource, "/registry/pods/#{namespace_name}/#{resource_name}")
+  when "k8s.io/ComponentStatus"
+    run_insert(resource, "/registry/componentstatuses/#{resource_name}")
+  when "k8s.io/CSINode"
+    run_insert(resource, "/registry/csinodes/#{resource_name}")
+  when "k8s.io/ClusterRoleBinding"
+    run_insert(resource, "/registry/clusterrolebindings/#{resource_name}")
+  when "k8s.io/ClusterRole"
+    run_insert(resource, "/registry/clusterroles/#{resource_name}")
+  when "k8s.io/RoleBinding"
+    run_insert(resource, "/registry/rolebindings/#{namespace_name}/#{resource_name}")
+  when "k8s.io/Role"
+    run_insert(resource, "/registry/roles/#{namespace_name}/#{resource_name}")
+  when "k8s.io/Secret"
+    run_insert(resource, "/registry/secrets/#{namespace_name}/#{resource_name}")
+  when "k8s.io/ServiceAccount"
+    run_insert(resource, "/registry/serviceaccounts/#{namespace_name}/#{resource_name}")
+  when "k8s.io/Service"
+    run_insert(resource, "/registry/services/specs/#{namespace_name}/#{resource_name}")
+  when "k8s.io/Endpoints"
+    run_insert(resource, "/registry/services/endpoints/#{namespace_name}/#{resource_name}")
+  when "k8s.io/Event"
+    run_insert(resource, "/registry/events/#{namespace_name}/#{resource_name}")
+  when "k8s.io/ConfigMap"
+    run_insert(resource, "/registry/configmaps/#{namespace_name}/#{resource_name}")
+  when "k8s.io/EndpointSlice"
+    run_insert(resource, "/registry/endpointslices/#{namespace_name}/#{resource_name}")
+  when "k8s.io/Namespace"
+    run_insert(resource, "/registry/namespaces/#{resource_name}")
+  when "k8s.io/StorageClass"
+    run_insert(resource, "/registry/storageclasses/#{resource_name}")
+  when "k8s.io/APIService"
+    run_insert(resource, "/registry/apiregistration.k8s.io/apiservices/#{resource_name}")
+  when "k8s.io/PriorityClass"
+    run_insert(resource, "/registry/priorityclasses/#{resource_name}")
+  when "k8s.io/Lease"
+    run_insert(resource, "/registry/masterleases/#{resource_name}")
+  when "k8s.io/Version"
+    # skip
+  else
+    puts "Skipping: #{line.to_s[0, 50]}" 
+  end
+end
+
+def parse_input_file(file)
+  IO.foreach(file) do |line|
+    if JSON.parse(line)
+      parse_line(line)
+    else
+      puts "ERROR parsing: #{line.to_s}"
+      puts "EXITING"
+      exit 1
+    end
+  end
+end
+
+if ARGV.empty?
+  puts "No input file passed as first argument. Exiting."
+  exit 1
+else
+  parse_input_file(ARGV[0])
+end

support/load.rb

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+honk,honk,honk,system:masters