/spring-cloud-vault

Configuration Integration with HashiCorp Vault

Primary LanguageJavaApache License 2.0Apache-2.0

Features

Spring Cloud Vault Config Client

Specifically for Spring applications:

Quick Start

This section explains how to get you started with Vault and Spring Cloud Vault.

Prerequisites

To get started with Vault and this guide you need a *NIX-like operating systems that provides:

  • wget, openssl and unzip

  • at least Java 8 and a properly configured JAVA_HOME environment variable

Note
 This guide explains Vault setup from a Spring Cloud Vault perspective for integration testing. You can find a getting started guide directly on the Vault project site: https://learn.hashicorp.com/vault

Install Vault

$ wget https://releases.hashicorp.com/vault/${vault_version}/vault_${vault_version}_${platform}.zip
$ unzip vault_${vault_version}_${platform}.zip
Note
 These steps can be achieved by downloading and running install_vault.sh.

Create SSL certificates for Vault

Next, you’re required to generate a set of certificates:

  • Root CA

  • Vault Certificate (decrypted key work/ca/private/localhost.decrypted.key.pem and certificate work/ca/certs/localhost.cert.pem)

Make sure to import the Root Certificate into a Java-compliant truststore.

The easiest way to achieve this is by using OpenSSL.

Note
 create_certificates.sh creates certificates in work/ca and a JKS truststore work/keystore.jks. If you want to run Spring Cloud Vault using this quickstart guide you need to configure the truststore the spring.cloud.vault.ssl.trust-store property to file:work/keystore.jks.

Start Vault server

Next create a config file along the lines of:

backend "inmem" {
}

listener "tcp" {
  address = "0.0.0.0:8200"
  tls_cert_file = "work/ca/certs/localhost.cert.pem"
  tls_key_file = "work/ca/private/localhost.decrypted.key.pem"
}

disable_mlock = true
Note
 You can find an example config file at vault.conf. 
$ vault server -config=vault.conf

Vault is started listening on 0.0.0.0:8200 using the inmem storage and https. Vault is sealed and not initialized when starting up.

Note
 If you want to run tests, leave Vault uninitialized. The tests will initialize Vault and create a root token 00000000-0000-0000-0000-000000000000.

If you want to use Vault for your application or give it a try then you need to initialize it first.

$ export VAULT_ADDR="https://localhost:8200"
$ export VAULT_SKIP_VERIFY=true # Don't do this for production
$ vault operator init

You should see something like:

Key 1: 7149c6a2e16b8833f6eb1e76df03e47f6113a3288b3093faf5033d44f0e70fe701
Key 2: 901c534c7988c18c20435a85213c683bdcf0efcd82e38e2893779f152978c18c02
Key 3: 03ff3948575b1165a20c20ee7c3e6edf04f4cdbe0e82dbff5be49c63f98bc03a03
Key 4: 216ae5cc3ddaf93ceb8e1d15bb9fc3176653f5b738f5f3d1ee00cd7dccbe926e04
Key 5: b2898fc8130929d569c1677ee69dc5f3be57d7c4b494a6062693ce0b1c4d93d805
Initial Root Token: 19aefa97-cccc-bbbb-aaaa-225940e63d76

Vault initialized with 5 keys and a key threshold of 3. Please
securely distribute the above keys. When the Vault is re-sealed,
restarted, or stopped, you must provide at least 3 of these keys
to unseal it again.

Vault does not store the master key. Without at least 3 keys,
your Vault will remain permanently sealed.

Vault will initialize and return a set of unsealing keys and the root token. Pick 3 keys and unseal Vault. Store the Vault token in the VAULT_TOKEN environment variable.

$ vault operator unseal (Key 1)
$ vault operator unseal (Key 2)
$ vault operator unseal (Key 3)
$ export VAULT_TOKEN=(Root token)
# Required to run Spring Cloud Vault tests after manual initialization
$ vault token create -id="00000000-0000-0000-0000-000000000000" -policy="root"

Spring Cloud Vault accesses different resources. By default, the secret backend is enabled which accesses secret config settings via JSON endpoints.

The HTTP service has resources in the form:

/secret/{application}/{profile}
/secret/{application}
/secret/{defaultContext}/{profile}
/secret/{defaultContext}

where the "application" is injected as the spring.application.name in the SpringApplication (i.e. what is normally "application" in a regular Spring Boot app), "profile" is an active profile (or comma-separated list of properties). Properties retrieved from Vault will be used "as-is" without further prefixing of the property names.

Client Side Usage

To use these features in an application, just build it as a Spring Boot application that depends on spring-cloud-vault-config (e.g. see the test cases). Example Maven configuration:

pom.xml
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>${springBootVersion}</version>
    <relativePath /> <!-- lookup parent from repository -->
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-vault-config</artifactId>
        <version>{project-version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

<!-- repositories also needed for snapshots and milestones -->

Then you can create a standard Spring Boot application, like this simple HTTP server:

@SpringBootApplication
@RestController
public class Application {

    @RequestMapping("/")
    public String home() {
        return "Hello World!";
    }

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

When it runs it will pick up the external configuration from the default local Vault server on port 8200 if it is running. To modify the startup behavior you can change the location of the Vault server using application.properties, for example

application.yml
spring.cloud.vault:
    host: localhost
    port: 8200
    scheme: https
    uri: https://localhost:8200
    connection-timeout: 5000
    read-timeout: 15000
spring.config.import: vault://

  • host sets the hostname of the Vault host. The host name will be used for SSL certificate validation

  • port sets the Vault port

  • scheme setting the scheme to http will use plain HTTP. Supported schemes are http and https.

  • uri configure the Vault endpoint with an URI. Takes precedence over host/port/scheme configuration

  • connection-timeout sets the connection timeout in milliseconds

  • read-timeout sets the read timeout in milliseconds

  • spring.config.import mounts Vault as PropertySource using all enabled secret backends (key-value enabled by default)

Enabling further integrations requires additional dependencies and configuration. Depending on how you have set up Vault you might need additional configuration like SSL and authentication.

If the application imports the spring-boot-starter-actuator project, the status of the vault server will be available via the /health endpoint.

The vault health indicator can be enabled or disabled through the property management.health.vault.enabled (default to true).

Note
 With Spring Cloud Vault 3.0 and Spring Boot 2.4, the bootstrap context initialization (bootstrap.yml, bootstrap.properties) of property sources was deprecated. Instead, Spring Cloud Vault favors Spring Boot’s Config Data API which allows importing configuration from Vault. With Spring Boot Config Data approach, you need to set the spring.config.import property in order to bind to Vault. You can read more about it in the Config Data Locations section. You can enable the bootstrap context either by setting the configuration property spring.cloud.bootstrap.enabled=true or by including the dependency org.springframework.cloud:spring-cloud-starter-bootstrap.

Authentication

Spring Cloud Vault supports multiple authentication mechanisms to authenticate applications with Vault.

For a quickstart, use the root token printed by the Vault initialization.

application.yml
spring.cloud.vault:
    token: 19aefa97-cccc-bbbb-aaaa-225940e63d76
spring.config.import: vault://
Warning
 Consider carefully your security requirements. Static token authentication is fine if you want quickly get started with Vault, but a static token is not protected any further. Any disclosure to unintended parties allows Vault use with the associated token roles.

Building

Build requirements for Vault

Spring Cloud Vault Config requires SSL certificates and a running Vault instance listening on localhost:8200. Certificates and the Vault setup are scripted, the scripts are located in src/test/bash.

The following scripts need to be run prior to building the project for the tests to pass.

$ ./src/test/bash/install_vault.sh
$ ./src/test/bash/create_certificates.sh
$ ./src/test/bash/local_run_vault.sh

Leave Vault uninitialized, the tests will initialize and unseal Vault. They will also create a root token 00000000-0000-0000-0000-000000000000.

Changes to the documentation should be made to the adocs found under docs/src/main/asciidoc/

README.adoc can be re-generated via the following

$ ./docs/src/main/ruby/generate_readme.sh > README.adoc

This script requires ruby and the asciidoctor gem installed (gem install asciidoctor)

Building

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Contributing

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