juntaki / kms-vault

A tool for using Cloud KMS to manage configuration files that partially contain sensitive information in the repository

kms-vault

kms-vault allows you to manage configuration files that partially contain confidential information in a repository using Cloud KMS. You can apply Ansible vault best practices and encryption key sharing for team development using Cloud KMS. The commands are made almost compatible for ansible-vault, so the migration is easy.

Install

curl -sfL https://raw.githubusercontent.com/juntaki/kms-vault/master/install.sh | sh

Basic usage

Follow the steps in Cloud KMS Documentation to create a key ring and a key. Write the string you want to encrypt into a file to encrypt it.

> echo secret! > secret-file
> cat secret-file
secret!

> # Encryption
> kms-vault encrypt --project <your-project-name> --location <location> --keyring <your-keyring> --key <your-key> secret-file
> cat secret-file
$VAULT;0.1.0;CLOUD_KMS
CiQAX7XZ1ruzQYWP6my24jdc6BHt+tMifMzQVEOi1QROl4fzyAMSMQDKS25uyx7kqF8v/VcqwV3n2mhzl9Wm13voO5dgb0EeJZk489GAV9RoWWuinHeJxhE=

> # Decription
> kms-vault decrypt --project <your-project-name> --location <location> --keyring <your-keyring> --key <your-key> secret-file
> cat secret-file
secret!

Save the repository secret

kms-vault configration

Project, location, keyring, and key can be saved as configuration file for the repository. Put the file in the project root.

> # Write your config to .kms-vault.yaml
> kms-vault config --project <your-project-name> --location <location> --keyring <your-keyring> --key <your-key> -w
> cat .kms-vault.yaml 
project: your-project-name
location: location
keyring: your-keyring
key: your-key

Ansible best practice

Only the secret information is extracted and saved to vault.yaml in YAML format. vars.yaml is a template configuration file that does not contain any secret information.

├── vars.yaml
└── vault.yaml

vault.yaml gives a name to each of the secrets. (The extension must be yaml or yml in this case.) To see the vault.yaml in an encrypted state, use the view command. You can use the --yaml option to check the values used for embedding a template. The file name is lower-cased without the extension, and the namespace is automatically split.

> kms-vault view vault.yaml
secret: secret-text

> kms-vault view --yaml vault.yaml
vault:
  secret: secret-text

vars.yaml is Go's text/template format, and you can get the output with the fill command.

> cat vars.yaml 
plain_text: not-secret-text
secret: {{.vault.secret}}
> kms-vault fill --template vars.yaml vault.yaml 
plain_text: not-secret-text
secret: secret-text