AWS IAM managed EC2 SSH access

This approach will sync public ssh keys for user and groups from IAM account to an S3 bucket as authorized_keys files. On the ssh daemon side AuthorizedKeysCommand is used to request authorized keys from S3 bucket on demand on ssh connection establishment. So you can manage all ssh key access to your instances via IAM.

  https://github.com/qoomon/aws-ec2-ssh-iam