bastrd - bastion server for secure environments

bastrd builds on top of the ideas behind keymaker and toolbox to build a secure shared bastion server for restricted environments.

⚠️ bastrd is in early development stage

How does it work?

bastrd has 3 components:

1. bastrd sync, an agent to sync AWS IAM groups and users to Linux
2. bastrd authorized-keys, SSH authorized keys command to authenticate the user login against AWS IAM registered SSH Public Keys and groups
3. bastrd toolbox, a session wrapper for a customizable toolbox container, the user must provide an AWS IAM account MFA token for authentication and setup of the session scoped credentials.

Toolbox features

The toolbox container has the following features:

• Validates MFA against user's AWS IAM MFA device
• Create temporary user session AWS credentials
• Write temporary credentials as /home/<username>/.aws/ for easy of use
• Customizable session container image for advanced tools, check Dockerfile.toolbox for the default settings
• Session resuming, for easier recovery of connections issues
• SSH-agent forwarding (note: doesn't work on session resuming)
• Firewall rule to block containers from hijacking the AWS EC2 instance profile used by bastrd itself
• Reduced container capabilities for improved security, e.g., no socket binding

Installing on AWS with Terraform

This repository was configured to be used as a quick way to create a bastrd instance on your AWS environment, fork it and customize as necessary.

1. Clone this repo
2. Configure main.tf with your state and terrraform.tfvars for your desired settings and run terraform init
3. Run terraform apply to bootstrap the CoreOS instance and setup required AWS IAM groups
4. Now wait a few minutes while your instance starts and connect to it via ssh -A my-iam-username@$(terraform output)

Uninstall

1. terraform destroy to remove instance and related resources