Simple Jenkins pipeline on AWS (Part 1)

This tutorial serie should enable you to create own pipelines via Jenkins on AWS. Therefore we try to catch all needed basics with AWS IAM, EC2, ECR and ECS. Some of our configurations are recommended only for learning purpose, don’t use them on production! Why? Because these lessons are for people who starts on these topics and I will try to make all steps/configuration as easy as possible without focus on security. In this part we will create the environment and setup the “build step”.

Preconditions

  • AWS account (eq. free tier)
  • Git account (eq. GitLab, Bitbucket, GitHub, etc.)

AWS IAM

The first preparation you do on AWS IAM Management Console. Here you create and configure a new group. The benefit of this group is that you can reconfigure the policies for assigned users easily at anytime. Please name the group “PipelineExampleGroup”.

AWS IAM group name

Now search for EC2 Container Registry policies and enable checkbox for “AmazonEC2ContainerRegistryPowerUser”. For our example this policy is enough, but for production please don’t do that!

AWS IAM group policies

After the group is created, a user needs to be assigned to this group. Name the user “PipelineExampleUser”. Please enable checkbox “Programmatic access” for this user.

AWS IAM user name

Assign the user to group.

AWS IAM user group

Before you finish the process, please choose Download .csv and then save the file to a safe location.

AWS Jenkins EC2 Instance

Now you can launch our EC2 instance. Do this on region “Frankfurt” (eu-central-1). Of course you can choose any other region, but please remember your choice later. At very first step select the template “Amazon Linux 2 AMI (HVM), SSD Volume Type”.

AWS EC2 AMI

The instance type “t2.micro” is enough for our example. For production you will need something else – depending to your needs.

AWS EC2 instance type

Now you need to be a little bit careful. On Instance Details step please select “Enable” for “Auto-assign Public IP” and “Stop” for “Shutdown Behavior”. For all other values the defaults should be fine. I select my default VPC and “No preference…” for Subnet.

AWS EC2 instance details

15 Gb disk space are fine. For production you need to estimate differently.

AWS EC2 instance storage

With the tag you will have it easier to identify the instance later on console view. Enter values “Name” for “Key” and “Jenkins” for “Value”.

AWS EC2 instance tags

Create a new security group with name “ExampleSecurityGroup” and allow ports 22, 80 and 8080 (IPv4 only). You can change the configuration at any time later. On a production environment you should use other ports like 443 and IP restrictions.

AWS EC2 instance security group

Create a new key pair with name “ExampleKeyPair”. Don’t forget to save the key (“Download Key Pair”) and press “Launch Instances”!

AWS EC2 instance key pair

Install and run Jenkins

The EC2 instance is running and you can connect via SSH to start all needed installations and configurations. Attention: Your Public IP/DNS will be different (also after every stop/start), via button “Connect” you can easily figure out your configuration. I will just use the term “<EC2 IP|DNS>” in my description.

AWS EC2 connection

Note: I have a space after etc, because of security settings of my provider.

Do not close the SSH connection yet. Start your browser and following there the Jenkins installation steps. The URL is similar to your SSH connection – http://<EC2 IP|DNS>:8080. You should see the following screen and paste the initial password there.

jenkins screen initial password

On next screen press button “Install suggested plugins” and wait for the screen to create administrator account. Fill in your credentials and finish the installation steps. The remaining configurations (on browser) will be made later.

AWS ECR

Before you can push images to ECR, you need to create a new repository. On the ECR page, choose button “Create repository”. Your AWS ECR console screen could look a little bit different.

AWS ECR repositories

Give a repository name “example/nginx” and press button “Create repository”.

AWS ECR repository configuration

Done, your ECR repository is already created. You can see on overview page all needed informations like Repository name and URI. Your repository URI will be different to my. I will just use the term “<ECR URI>” in my description.

AWS ECR repository overview

Okay, now enable user jenkins to connect to ECR. Go back to terminal and execute following steps. You need now the credentials from downloaded csv file for “PipelineExampleUser”.

Git Repository

I assume that you are familiar with Git. You must now create a Git Repository and create the following folders and files there. I will use my own private GitLab repository.

Content of files in root folder:

Content of files in cicd folder:

Note: Please set permission rights for shell scripts like $ chmod +x build.sh deploy.sh test.sh

Inside folder “dev_credentials” I store the credentials.csv from AWS. The content of this folder will be only on my local machine, because via .gitignore I exclude the folder and files from git.

Jenkins job configuration

I will not use this tutorial to explain security topics for Jenkins, so we start directly with the configuration of the job (resp. project). On main page press now button “New item” or link “create new jobs”. Insert name “ExamplePipeline”, select “Pipeline” and press button “OK”.

jenkins new job

To save some disk space enable checkbox discard old builds (5 builds are enough).

jenkins job discard old builds

Normally you would create a webhook to trigger the build after commit, but our EC2 instance does change the public IP/DNS on every stop/start. That’s why here we check the revision changes every 5 minutes on git and trigger the job if something has changed.

jenkins job build trigger

Add the repository (may credentials are needed), configure the branch and Jenkinsfile path.

jenkins job scm pipeline

Press button “save”, _cross fingers_ and trigger manual the build. If you did nothing wrong, the job will run without issues and the ECR contains your images (depending how often you trigger the build).

AWS ECR repository images

The next part of this tutorial series will be about deployment to ECS.

File encryption/decryption using GPG

There are just too many people and organizations who are interested in our data. Thus, the secure transmission of data is important. Through encryption/decryption, data can be protected from access by third parties. There are already very long easy ways for the encryption/decryption but I have to find again and again that these are quite unknown. Herewith a little tutorial where I want to show possibilities by means of GPG.

Requirements

  • Docker (latest)

Environment preparation

By means of two Docker containers, we now want to simulate 2 persons who exchange the encrypted data.

Container (user_a)

Container (user_b)

No passphrase prompt

If you want to use the encryption/decryption without prompt, for example in a bash script, you can use the following options. Depending on the version, it can come to a distinction. Option 1 is by default not available in the Docker containers.

Multiple files

You can also use a simple loop to encrypt/decrypt multiple files. Please note the available GPG version/options. Here now a simple example without prompt.

Encryption and Decryption via keys

Container (user_a)

Container (user_b)

Both public keys are available.

Both clients need to import the public key from other.

Our user_a now encrypt data.

User_b now decrypt data.

I hope that you have found an entry point into the topic and I have woken up your interest.

Troubleshoot SELinux Centos7 Apache

On my test environment, I had an permission denied issue with a simple HTML file. Shit all permissions looking good … but wait a minute SELinux was activated and I did not want to disable it. Here is the simple solution.

Cool … the problem is solved. All pages are visible without permission issues. It also works recursively if several files are affected.

Vagrant and Vault

I was a little surprised why there is no Vagrant plug-in for Vault. Then I thought no matter, because the Vagrantfile is actually a Ruby script. Let me try it. I have to say right away that I’m not a Ruby developer! But here is my solution which has brought me to the goal.

Prerequisite

  • latest Vault installed (0.11.0)
  • latest Vagrant installed (2.1.3)

Prepare project and start Vault

Here my simple vagrant policy (don’t do that in production).

And here is my crazy and fancy Vagrantfile

Configure Vault

Run it

😉 … it just works

Docker registry and Let’s Encrypt

In a previous tutorial, I showed you how to setup a insecure Docker registry. Now we will use HTTPS via certificates from Let’s Encrypt and without some insecure registry settings.

Order dedicated host

If you have a host already, skip this section. If you looking for an good and cheap dedicated host, have a look on Dedibox.

Dedibox

After successful order you can start to install CentOS (Server distributions).

install os on Dedibox

When the OS installation is done, please take care for security! On tecmint.com you can find some cool guides “The Mega Guide To Harden and Secure CentOS 7“. On official Docker docs you will found all needed steps for your Docker CE installation.

Register and configure free domain

Let’s Encrypt need a domain! Register on Freenom and order new domain for free (.tk, .ml, .ga, .cf, .gq). If you have a domain already, skip this section.

free domain

Ensure your dns is configured correctly!

Freenom dns management

Create new Let’s Encrypt certificates

Login into your host via SSH and follow next steps. Attention, replace “demotesthost.tk” by your own domain!

Note: The space after /etc is just because of security settings by my provider!

Run your Docker registry

Now it’s time for push and pull a images

After download and open Finder, you should see similar files.

letsencrypt  CA certificates

Simply install both CA certificates via double-click.

letsencrypt certificate install

Optional you can check via “Keychain Access.app”.

Keychain Access.app

Now restart local docker and try again.

… next steps

So what about authentication? Currently everybody can upload/download images! What that means for security, should be clear. Please read the Docker docs about.

Shell linter evaluation and usage

Tomorrow, the 1st of August is a national holiday in Switzerland … So I do one day off and have some time. For a long time I wanted to deal with Shell lint. After some research, i found a few open-source tools. By the way … linters are being written for many programming languages and document formats.

Preparation

For evaluation i will not install the tools on my local system,… so Vagrant (with CentOS 7) is my choice.

Note: I created the Vagrant box “lupin/centos” via Packer … here my GitHub repository.

Shell option -n

Many shell’s already offer a very simple script analysis. The option -n read commands in script, but do not execute them (syntax check).

Okay … but not really what I want… (more details are welcome)

shlint and checkbashisms

I found the repository here.

Note: for both tools you should change the shebang to “#!/bin/sh”

For shlint… I don’t get it. For checkbashisms … good if will write portable Shell scripts.

bashate

I found it here on Pypi.

Nice … but not really all Standards.

Shellsheck

Shellcheck is known! Here the online service and here the repository.

I stay with that tool. Currently there are packages for almost every known OS.

Additional

Who knows me … knows that I do not like Installer and prefer Docker use. Here’s some fun.

😉 just for fun…

Install Ansible inside virtualenv on CentOS7

There are many ways to install Ansible inside virtualenv on CentOS7, I would like to show now a very simple variant. Important are actually the CentOS packages at the beginning.

Steps

it can be so easy 😉

Lunar – a UNIX security auditing tool

LUNAR is a open source UNIX security auditing tool written in Shell script. It offers the audit for various operating systems like Linux (RHEL, CentOS, Debian, Ubuntu), Solaris and Mac OS with less requirements. Services like Docker and AWS are also supported.

Download

Clone repository

Download via curl

Usage

The use is very easy…