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Spring Cloud Vault Config provides client-side support for externalized configuration in a distributed system. With HashiCorp’s Vault you have a central place to manage external secret properties for applications across all environments. Vault can manage static and dynamic secrets such as username/password for remote applications/resources and provide credentials for external services such as MySQL, PostgreSQL, Apache Cassandra, Couchbase, MongoDB, Consul, AWS and more.
1. New & Noteworthy
This section briefly covers items that are new and noteworthy in the latest releases.
1.1. New in Spring Cloud Vault 3.0
-
Migration of
PropertySource
initialization from Spring Cloud’s Bootstrap Context to Spring Boot’s ConfigData API. -
Support for the Couchbase Database backend.
-
Configuration of keystore/truststore types through
spring.cloud.vault.ssl.key-store-type=…
/spring.cloud.vault.ssl.trust-store-type=…
including PEM support. -
Support for
ReactiveDiscoveryClient
by configuring aReactiveVaultEndpointProvider
. -
Support to configure Multiple Databases.
2. Quick Start
Prerequisites
To get started with Vault and this guide you need a *NIX-like operating systems that provides:
-
wget
,openssl
andunzip
-
at least Java 8 and a properly configured
JAVA_HOME
environment variable
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: 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
These steps can be achieved by downloading and running install_vault.sh .
|
Create SSL certificates for Vault
Next, you’r required to generate a set of certificates:
-
Root CA
-
Vault Certificate (decrypted key
work/ca/private/localhost.decrypted.key.pem
and certificatework/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.
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
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.
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.
3. 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:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.4.0.RELEASE</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-vault-config</artifactId>
<version>3.1.4-SNAPSHOT</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
spring.cloud.vault:
host: localhost
port: 8200
scheme: https
uri: https://localhost:8200
connection-timeout: 5000
read-timeout: 15000
config:
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 tohttp
will use plain HTTP. Supported schemes arehttp
andhttps
. -
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 asPropertySource
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
).
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 .
|
3.1. Authentication
Vault requires an authentication mechanism to authorize client requests.
Spring Cloud Vault supports multiple authentication mechanisms to authenticate applications with Vault.
For a quickstart, use the root token printed by the Vault initialization.
spring.cloud.vault:
token: 19aefa97-cccc-bbbb-aaaa-225940e63d76
spring.config.import: vault://
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. |
4. ConfigData API
Spring Boot provides since version 2.4 a ConfigData API that allows the declaration of configuration sources and importing these as property sources.
Spring Cloud Vault uses as of version 3.0 the ConfigData API to mount Vault’s secret backends as property sources. In previous versions, the Bootstrap context was used. The ConfigData API is much more flexible as it allows specifying which configuration systems to import and in which order.
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 .
Using the boostrap context should be only rarely required hence we recommend using the Config Data API for more flexibility regarding property source ordering.
|
4.1. ConfigData Locations
You can mount Vault configuration through one or more PropertySource
that are materialized from Vault.
Spring Cloud Vault supports two config locations:
-
vault://
(default location) -
vault:///<context-path>
(contextual location)
Using the default location mounts property sources for all enabled Secret Backends.
Without further configuration, Spring Cloud Vault mounts the key-value backend at /secret/${spring.application.name}
.
Each activated profile adds another context path following the form /secret/${spring.application.name}/${profile}
.
Adding further modules to the classpath, such as spring-cloud-config-databases
, provides additional secret backend configuration options which get mounted as property sources if enabled.
If you want to control which context paths are mounted from Vault as PropertySource
, you can either use a contextual location (vault:///my/context/path
) or configure a VaultConfigurer
.
Contextual locations are specified and mounted individually.
Spring Cloud Vault mounts each location as a unique PropertySource
.
You can mix the default locations with contextual locations (or other config systems) to control the order of property sources.
This approach is useful in particular if you want to disable the default key-value path computation and mount each key-value backend yourself instead.
spring.config.import: vault://first/context/path, vault://other/path, vault://
Property names within a Spring Environment
must be unique to avoid shadowing.
If you use the same secret names in different context paths and you want to expose these as individual properties you can distinguish them by adding a prefix
query parameter to the location.
spring.config.import: vault://my/path?prefix=foo., vault://my/other/path?prefix=bar.
secret: ${foo.secret}
other.secret: ${bar.secret}
Prefixes are added as-is to all property names returned by Vault. If you want key names to be separated with a dot between the prefix and key name, make sure to add a trailing dot to the prefix. |
4.2. Conditionally enable/disable Vault Configuration
In some cases, it can be required to launch an application without Vault. You can express whether a Vault config location should be optional or mandatory (default) through the location string:
-
optional:vault://
(default location) -
optional:vault:///<context-path>
(contextual location)
Optional locations are skipped during application startup if Vault support was disabled through spring.cloud.vault.enabled=false
.
Vault context paths that cannot be found (HTTP Status 404) are skipped regardless of whether the config location is marked optional. Vault Client Fail Fast allows failing on start if a Vault context path cannot be found because of HTTP Status 404. |
4.3. Infrastructure Customization
Spring Cloud Vault requires infrastructure classes to interact with Vault. When not using the ConfigData API (meaning that you haven’t specified spring.config.import=vault://
or a contextual Vault path), Spring Cloud Vault defines its beans through VaultAutoConfiguration
and VaultReactiveAutoConfiguration
.
Spring Boot bootstraps the application before a Spring Context is available. Therefore VaultConfigDataLoader
registers beans itself to propagate these later on into the application context.
You can customize the infrastructure used by Spring Cloud Vault by registering custom instances using the Bootstrapper
API:
ClientHttpRequestFactory
ClientOptions options = new ClientOptions();
SslConfiguration sslConfiguration = SslConfiguration.unconfigured();
HttpClientBuilder builder = HttpComponents.getHttpClientBuilder(options, sslConfiguration);
InstanceSupplier<ClientFactoryWrapper> supplier = context ->
new ClientFactoryWrapper(new HttpComponentsClientHttpRequestFactory(builder.build()));
SpringApplication application = new SpringApplication(MyApplication.class);
application.addBootstrapRegistryInitializer(registry -> registry.register(ClientFactoryWrapper.class, supplier));
RestTemplateBuilder
InstanceSupplier<RestTemplateBuilder> supplier = context -> {
return RestTemplateBuilder
.builder()
.requestFactory(context.get(ClientFactoryWrapper.class).getClientHttpRequestFactory())
.defaultHeader("X-Vault-Namespace", "my-namespace");
};
SpringApplication application = new SpringApplication(MyApplication.class);
application.addBootstrapRegistryInitializer(registry -> registry.register(RestTemplateBuilder.class, supplier));
See also Customize which secret backends to expose as PropertySource and the source of VaultConfigDataLoader
for customization hooks.
5. Authentication methods
Different organizations have different requirements for security and authentication. Vault reflects that need by shipping multiple authentication methods. Spring Cloud Vault supports token and AppId authentication.
5.1. Token authentication
Tokens are the core method for authentication within Vault.
Token authentication requires a static token to be provided using the configuration.
As a fallback, the token may also be retrieved from ~/.vault-token
which is the default location used by the Vault CLI to cache tokens.
Token authentication is the default authentication method. If a token is disclosed an unintended party gains access to Vault and can access secrets for the intended client. |
spring.cloud.vault:
authentication: TOKEN
token: 00000000-0000-0000-0000-000000000000
-
authentication
setting this value toTOKEN
selects the Token authentication method -
token
sets the static token to use. If missing or empty, then an attempt will be made to retrieve a token from ~/.vault-token.
See also:
5.2. Vault Agent authentication
Vault ships a sidecar utility with Vault Agent since version 0.11.0. Vault Agent implements the functionality of Spring Vault’s SessionManager
with its Auto-Auth feature.
Applications can reuse cached session credentials by relying on Vault Agent running on localhost
.
Spring Vault can send requests without the
X-Vault-Token
header.
Disable Spring Vault’s authentication infrastructure to disable client authentication and session management.
spring.cloud.vault:
authentication: NONE
-
authentication
setting this value toNONE
disablesClientAuthentication
andSessionManager
.
See also: Vault Documentation: Agent
5.3. AppId authentication
Vault supports AppId
authentication that consists of two hard to guess tokens.
The AppId defaults to spring.application.name
that is statically configured.
The second token is the UserId which is a part determined by the application, usually related to the runtime environment.
IP address, Mac address or a Docker container name are good examples.
Spring Cloud Vault Config supports IP address, Mac address and static UserId’s (e.g. supplied via System properties).
The IP and Mac address are represented as Hex-encoded SHA256 hash.
IP address-based UserId’s use the local host’s IP address.
spring.cloud.vault:
authentication: APPID
app-id:
user-id: IP_ADDRESS
-
authentication
setting this value toAPPID
selects the AppId authentication method -
app-id-path
sets the path of the AppId mount to use -
user-id
sets the UserId method. Possible values areIP_ADDRESS
,MAC_ADDRESS
or a class name implementing a customAppIdUserIdMechanism
The corresponding command to generate the IP address UserId from a command line is:
$ echo -n 192.168.99.1 | sha256sum
Including the line break of echo leads to a different hash value so make sure to include the -n flag.
|
Mac address-based UserId’s obtain their network device from the localhost-bound device.
The configuration also allows specifying a network-interface
hint to pick the right device.
The value of
network-interface
is optional and can be either an interface name or interface index (0-based).
spring.cloud.vault:
authentication: APPID
app-id:
user-id: MAC_ADDRESS
network-interface: eth0
-
network-interface
sets network interface to obtain the physical address
The corresponding command to generate the IP address UserId from a command line is:
$ echo -n 0AFEDE1234AC | sha256sum
The Mac address is specified uppercase and without colons.
Including the line break of echo leads to a different hash value so make sure to include the -n flag.
|
5.3.1. Custom UserId
The UserId generation is an open mechanism.
You can set
spring.cloud.vault.app-id.user-id
to any string and the configured value will be used as static UserId.
A more advanced approach lets you set spring.cloud.vault.app-id.user-id
to a classname.
This class must be on your classpath and must implement the org.springframework.cloud.vault.AppIdUserIdMechanism
interface and the createUserId
method.
Spring Cloud Vault will obtain the UserId by calling createUserId
each time it authenticates using AppId to obtain a token.
spring.cloud.vault:
authentication: APPID
app-id:
user-id: com.examlple.MyUserIdMechanism
public class MyUserIdMechanism implements AppIdUserIdMechanism {
@Override
public String createUserId() {
String userId = ...
return userId;
}
}
5.4. AppRole authentication
AppRole is intended for machine authentication, like the deprecated (since Vault 0.6.1) AppId authentication. AppRole authentication consists of two hard to guess (secret) tokens: RoleId and SecretId.
Spring Vault supports various AppRole scenarios (push/pull mode and wrapped).
RoleId and optionally SecretId must be provided by configuration, Spring Vault will not look up these or create a custom SecretId.
spring.cloud.vault:
authentication: APPROLE
app-role:
role-id: bde2076b-cccb-3cf0-d57e-bca7b1e83a52
The following scenarios are supported along the required configuration details:
Method |
RoleId |
SecretId |
RoleName |
Token |
Provided RoleId/SecretId |
Provided |
Provided |
||
Provided RoleId without SecretId |
Provided |
|||
Provided RoleId, Pull SecretId |
Provided |
Provided |
Provided |
Provided |
Pull RoleId, provided SecretId |
Provided |
Provided |
Provided |
|
Full Pull Mode |
Provided |
Provided |
||
Wrapped |
Provided |
|||
Wrapped RoleId, provided SecretId |
Provided |
Provided |
||
Provided RoleId, wrapped SecretId |
Provided |
Provided |
RoleId |
SecretId |
Supported |
Provided |
Provided |
✅ |
Provided |
Pull |
✅ |
Provided |
Wrapped |
✅ |
Provided |
Absent |
✅ |
Pull |
Provided |
✅ |
Pull |
Pull |
✅ |
Pull |
Wrapped |
❌ |
Pull |
Absent |
❌ |
Wrapped |
Provided |
✅ |
Wrapped |
Pull |
❌ |
Wrapped |
Wrapped |
✅ |
Wrapped |
Absent |
❌ |
You can use still all combinations of push/pull/wrapped modes by providing a configured AppRoleAuthentication bean within the context.
Spring Cloud Vault cannot derive all possible AppRole combinations from the configuration properties.
|
AppRole authentication is limited to simple pull mode using reactive infrastructure.
Full pull mode is not yet supported.
Using Spring Cloud Vault with the Spring WebFlux stack enables Vault’s reactive auto-configuration which can be disabled by setting spring.cloud.vault.reactive.enabled=false .
|
spring.cloud.vault:
authentication: APPROLE
app-role:
role-id: bde2076b-cccb-3cf0-d57e-bca7b1e83a52
secret-id: 1696536f-1976-73b1-b241-0b4213908d39
role: my-role
app-role-path: approle
-
role-id
sets the RoleId. -
secret-id
sets the SecretId. SecretId can be omitted if AppRole is configured without requiring SecretId (Seebind_secret_id
). -
role
: sets the AppRole name for pull mode. -
app-role-path
sets the path of the approle authentication mount to use.
5.5. AWS-EC2 authentication
The aws-ec2 auth backend provides a secure introduction mechanism for AWS EC2 instances, allowing automated retrieval of a Vault token. Unlike most Vault authentication backends, this backend does not require first-deploying, or provisioning security-sensitive credentials (tokens, username/password, client certificates, etc.). Instead, it treats AWS as a Trusted Third Party and uses the cryptographically signed dynamic metadata information that uniquely represents each EC2 instance.
spring.cloud.vault:
authentication: AWS_EC2
AWS-EC2 authentication enables nonce by default to follow the Trust On First Use (TOFU) principle. Any unintended party that gains access to the PKCS#7 identity metadata can authenticate against Vault.
During the first login, Spring Cloud Vault generates a nonce that is stored in the auth backend aside the instance Id. Re-authentication requires the same nonce to be sent. Any other party does not have the nonce and can raise an alert in Vault for further investigation.
The nonce is kept in memory and is lost during application restart.
You can configure a static nonce with spring.cloud.vault.aws-ec2.nonce
.
AWS-EC2 authentication roles are optional and default to the AMI.
You can configure the authentication role by setting the
spring.cloud.vault.aws-ec2.role
property.
spring.cloud.vault:
authentication: AWS_EC2
aws-ec2:
role: application-server
spring.cloud.vault:
authentication: AWS_EC2
aws-ec2:
role: application-server
aws-ec2-path: aws-ec2
identity-document: http://...
nonce: my-static-nonce
-
authentication
setting this value toAWS_EC2
selects the AWS EC2 authentication method -
role
sets the name of the role against which the login is being attempted. -
aws-ec2-path
sets the path of the AWS EC2 mount to use -
identity-document
sets URL of the PKCS#7 AWS EC2 identity document -
nonce
used for AWS-EC2 authentication. An empty nonce defaults to nonce generation
5.6. AWS-IAM authentication
The aws backend provides a secure authentication mechanism for AWS IAM roles, allowing the automatic authentication with vault based on the current IAM role of the running application. Unlike most Vault authentication backends, this backend does not require first-deploying, or provisioning security-sensitive credentials (tokens, username/password, client certificates, etc.). Instead, it treats AWS as a Trusted Third Party and uses the 4 pieces of information signed by the caller with their IAM credentials to verify that the caller is indeed using that IAM role.
The current IAM role the application is running in is automatically calculated. If you are running your application on AWS ECS then the application will use the IAM role assigned to the ECS task of the running container. If you are running your application naked on top of an EC2 instance then the IAM role used will be the one assigned to the EC2 instance.
When using the AWS-IAM authentication you must create a role in Vault and assign it to your IAM role.
An empty role
defaults to the friendly name the current IAM role.
spring.cloud.vault:
authentication: AWS_IAM
spring.cloud.vault:
authentication: AWS_IAM
aws-iam:
role: my-dev-role
aws-path: aws
server-name: some.server.name
endpoint-uri: https://sts.eu-central-1.amazonaws.com
-
role
sets the name of the role against which the login is being attempted. This should be bound to your IAM role. If one is not supplied then the friendly name of the current IAM user will be used as the vault role. -
aws-path
sets the path of the AWS mount to use -
server-name
sets the value to use for theX-Vault-AWS-IAM-Server-ID
header preventing certain types of replay attacks. -
endpoint-uri
sets the value to use for the AWS STS API used for theiam_request_url
parameter.
AWS-IAM requires the AWS Java SDK dependency (com.amazonaws:aws-java-sdk-core
) as the authentication implementation uses AWS SDK types for credentials and request signing.
5.7. Azure MSI authentication
The azure auth backend provides a secure introduction mechanism for Azure VM instances, allowing automated retrieval of a Vault token. Unlike most Vault authentication backends, this backend does not require first-deploying, or provisioning security-sensitive credentials (tokens, username/password, client certificates, etc.). Instead, it treats Azure as a Trusted Third Party and uses the managed service identity and instance metadata information that can be bound to a VM instance.
spring.cloud.vault:
authentication: AZURE_MSI
azure-msi:
role: my-dev-role
spring.cloud.vault:
authentication: AZURE_MSI
azure-msi:
role: my-dev-role
azure-path: azure
metadata-service: http://169.254.169.254/metadata/instance…
identity-token-service: http://169.254.169.254/metadata/identity…
-
role
sets the name of the role against which the login is being attempted. -
azure-path
sets the path of the Azure mount to use -
metadata-service
sets the URI at which to access the instance metadata service -
identity-token-service
sets the URI at which to access the identity token service
Azure MSI authentication obtains environmental details about the virtual machine (subscription Id, resource group, VM name) from the instance metadata service.
The Vault server has Resource Id defaults to vault.hashicorp.com
.
To change this, set spring.cloud.vault.azure-msi.identity-token-service
accordingly.
See also:
5.8. TLS certificate authentication
The cert
auth backend allows authentication using SSL/TLS client certificates that are either signed by a CA or self-signed.
To enable cert
authentication you need to:
-
Use SSL, see Vault Client SSL configuration
-
Configure a Java
Keystore
that contains the client certificate and the private key -
Set the
spring.cloud.vault.authentication
toCERT
spring.cloud.vault:
authentication: CERT
ssl:
key-store: classpath:keystore.jks
key-store-password: changeit
key-store-type: JKS
cert-auth-path: cert
5.9. Cubbyhole authentication
Cubbyhole authentication uses Vault primitives to provide a secured authentication workflow.
Cubbyhole authentication uses tokens as primary login method.
An ephemeral token is used to obtain a second, login VaultToken from Vault’s Cubbyhole secret backend.
The login token is usually longer-lived and used to interact with Vault.
The login token will be retrieved from a wrapped response stored at /cubbyhole/response
.
Creating a wrapped token
Response Wrapping for token creation requires Vault 0.6.0 or higher. |
$ vault token-create -wrap-ttl="10m"
Key Value
--- -----
wrapping_token: 397ccb93-ff6c-b17b-9389-380b01ca2645
wrapping_token_ttl: 0h10m0s
wrapping_token_creation_time: 2016-09-18 20:29:48.652957077 +0200 CEST
wrapped_accessor: 46b6aebb-187f-932a-26d7-4f3d86a68319
spring.cloud.vault:
authentication: CUBBYHOLE
token: 397ccb93-ff6c-b17b-9389-380b01ca2645
See also:
5.10. GCP-GCE authentication
The gcp auth backend allows Vault login by using existing GCP (Google Cloud Platform) IAM and GCE credentials.
GCP GCE (Google Compute Engine) authentication creates a signature in the form of a JSON Web Token (JWT) for a service account. A JWT for a Compute Engine instance is obtained from the GCE metadata service using Instance identification. This API creates a JSON Web Token that can be used to confirm the instance identity.
Unlike most Vault authentication backends, this backend does not require first-deploying, or provisioning security-sensitive credentials (tokens, username/password, client certificates, etc.). Instead, it treats GCP as a Trusted Third Party and uses the cryptographically signed dynamic metadata information that uniquely represents each GCP service account.
spring.cloud.vault:
authentication: GCP_GCE
gcp-gce:
role: my-dev-role
spring.cloud.vault:
authentication: GCP_GCE
gcp-gce:
gcp-path: gcp
role: my-dev-role
service-account: [email protected]
-
role
sets the name of the role against which the login is being attempted. -
gcp-path
sets the path of the GCP mount to use -
service-account
allows overriding the service account Id to a specific value. Defaults to thedefault
service account.
See also:
5.11. GCP-IAM authentication
The gcp auth backend allows Vault login by using existing GCP (Google Cloud Platform) IAM and GCE credentials.
GCP IAM authentication creates a signature in the form of a JSON Web Token (JWT) for a service account.
A JWT for a service account is obtained by calling GCP IAM’s projects.serviceAccounts.signJwt
API. The caller authenticates against GCP IAM and proves thereby its identity.
This Vault backend treats GCP as a Trusted Third Party.
IAM credentials can be obtained from either the runtime environment , specifically the GOOGLE_APPLICATION_CREDENTIALS
environment variable, the Google Compute metadata service, or supplied externally as e.g. JSON or base64 encoded.
JSON is the preferred form as it carries the project id and service account identifier required for calling projects.serviceAccounts.signJwt
.
spring.cloud.vault:
authentication: GCP_IAM
gcp-iam:
role: my-dev-role
spring.cloud.vault:
authentication: GCP_IAM
gcp-iam:
credentials:
location: classpath:credentials.json
encoded-key: e+KApn0=
gcp-path: gcp
jwt-validity: 15m
project-id: my-project-id
role: my-dev-role
service-account-id: [email protected]
-
role
sets the name of the role against which the login is being attempted. -
credentials.location
path to the credentials resource that contains Google credentials in JSON format. -
credentials.encoded-key
the base64 encoded contents of an OAuth2 account private key in the JSON format. -
gcp-path
sets the path of the GCP mount to use -
jwt-validity
configures the JWT token validity. Defaults to 15 minutes. -
project-id
allows overriding the project Id to a specific value. Defaults to the project Id from the obtained credential. -
service-account
allows overriding the service account Id to a specific value. Defaults to the service account from the obtained credential.
GCP IAM authentication requires the Google Cloud Java SDK dependency (com.google.apis:google-api-services-iam
and com.google.auth:google-auth-library-oauth2-http
) as the authentication implementation uses Google APIs for credentials and JWT signing.
Google credentials require an OAuth 2 token maintaining the token lifecycle.
All API is synchronous therefore, GcpIamAuthentication does not support AuthenticationSteps which is required for reactive usage.
|
See also:
5.12. Kubernetes authentication
Kubernetes authentication mechanism (since Vault 0.8.3) allows to authenticate with Vault using a Kubernetes Service Account Token. The authentication is role based and the role is bound to a service account name and a namespace.
A file containing a JWT token for a pod’s service account is automatically mounted at /var/run/secrets/kubernetes.io/serviceaccount/token
.
spring.cloud.vault:
authentication: KUBERNETES
kubernetes:
role: my-dev-role
kubernetes-path: kubernetes
service-account-token-file: /var/run/secrets/kubernetes.io/serviceaccount/token
-
role
sets the Role. -
kubernetes-path
sets the path of the Kubernetes mount to use. -
service-account-token-file
sets the location of the file containing the Kubernetes Service Account Token. Defaults to/var/run/secrets/kubernetes.io/serviceaccount/token
.
See also:
5.13. Pivotal CloudFoundry authentication
The pcf auth backend provides a secure introduction mechanism for applications running within Pivotal’s CloudFoundry instances allowing automated retrieval of a Vault token. Unlike most Vault authentication backends, this backend does not require first-deploying, or provisioning security-sensitive credentials (tokens, username/password, client certificates, etc.) as identity provisioning is handled by PCF itself. Instead, it treats PCF as a Trusted Third Party and uses the managed instance identity.
spring.cloud.vault:
authentication: PCF
pcf:
role: my-dev-role
spring.cloud.vault:
authentication: PCF
pcf:
role: my-dev-role
pcf-path: path
instance-certificate: /etc/cf-instance-credentials/instance.crt
instance-key: /etc/cf-instance-credentials/instance.key
-
role
sets the name of the role against which the login is being attempted. -
pcf-path
sets the path of the PCF mount to use. -
instance-certificate
sets the path to the PCF instance identity certificate. Defaults to${CF_INSTANCE_CERT}
env variable. -
instance-key
sets the path to the PCF instance identity key. Defaults to${CF_INSTANCE_KEY}
env variable.
PCF authentication requires BouncyCastle (bcpkix-jdk15on) to be on the classpath for RSA PSS signing. |
6. ACL Requirements
This section explains which paths are accessed by Spring Vault so you can derive your policy declarations from the required capabilities.
Capability | Associated HTTP verbs |
---|---|
create |
|
read |
|
update |
|
delete |
|
list |
|
6.1. Authentication
Login: POST auth/$authMethod/login
6.2. KeyValue Mount Discovery
GET sys/internal/ui/mounts/$mountPath
6.3. SecretLeaseContainer
SecretLeaseContainer
uses different paths depending on the configured lease endpoint.
LeaseEndpoints.Legacy
-
Revocation:
PUT sys/revoke
-
Renewal:
PUT sys/renew
LeaseEndpoints.Leases
(SysLeases
)
-
Revocation:
PUT sys/leases/revoke
-
Renewal:
PUT sys/leases/renew
6.4. Session Management
-
Token lookup:
GET auth/token/lookup-self
-
Renewal:
POST auth/token/renew-self
-
Revoke:
POST auth/token/revoke-self
7. Secret Backends
7.1. Key-Value Backend
Spring Cloud Vault supports both Key-Value secret backends, the versioned (v2) and unversioned (v1).
The key-value backend allows storage of arbitrary values as key-value store.
A single context can store one or many key-value tuples.
Contexts can be organized hierarchically.
Spring Cloud Vault determines itself whether a secret is using versioning and maps the path to its appropriate URL.
Spring Cloud Vault allows using the Application name, and a default context name (application
) in combination with active profiles.
/secret/{application}/{profile} /secret/{application} /secret/{default-context}/{profile} /secret/{default-context}
The application name is determined by the properties:
-
spring.cloud.vault.kv.application-name
-
spring.cloud.vault.application-name
-
spring.application.name
The profiles are determined by the properties:
-
spring.cloud.vault.kv.profiles
-
spring.profiles.active
Secrets can be obtained from other contexts within the key-value backend by adding their paths to the application name, separated by commas.
For example, given the application name usefulapp,mysql1,projectx/aws
, each of these folders will be used:
-
/secret/usefulapp
-
/secret/mysql1
-
/secret/projectx/aws
Spring Cloud Vault adds all active profiles to the list of possible context paths. No active profiles will skip accessing contexts with a profile name.
Properties are exposed like they are stored (i.e. without additional prefixes).
Spring Cloud Vault adds the data/ context between the mount path and the actual context path depending on whether the mount uses the versioned key-value backend.
|
spring.cloud.vault:
kv:
enabled: true
backend: secret
profile-separator: '/'
default-context: application
application-name: my-app
profiles: local, cloud
-
enabled
setting this value tofalse
disables the secret backend config usage -
backend
sets the path of the secret mount to use -
default-context
sets the context name used by all applications -
application-name
overrides the application name for use in the key-value backend -
profiles
overrides the active profiles for use in the key-value backend -
profile-separator
separates the profile name from the context in property sources with profiles
The key-value secret backend can be operated in versioned (v2) and non-versioned (v1) modes. |
See also:
7.2. Consul
Spring Cloud Vault can obtain credentials for HashiCorp Consul.
The Consul integration requires the spring-cloud-vault-config-consul
dependency.
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-vault-config-consul</artifactId>
<version>3.1.4-SNAPSHOT</version>
</dependency>
</dependencies>
The integration can be enabled by setting
spring.cloud.vault.consul.enabled=true
(default false
) and providing the role name with spring.cloud.vault.consul.role=…
.
The obtained token is stored in spring.cloud.consul.token
so using Spring Cloud Consul can pick up the generated credentials without further configuration.
You can configure the property name by setting spring.cloud.vault.consul.token-property
.
spring.cloud.vault:
consul:
enabled: true
role: readonly
backend: consul
token-property: spring.cloud.consul.token
-
enabled
setting this value totrue
enables the Consul backend config usage -
role
sets the role name of the Consul role definition -
backend
sets the path of the Consul mount to use -
token-property
sets the property name in which the Consul ACL token is stored
7.3. RabbitMQ
Spring Cloud Vault can obtain credentials for RabbitMQ.
The RabbitMQ integration requires the spring-cloud-vault-config-rabbitmq
dependency.
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-vault-config-rabbitmq</artifactId>
<version>3.1.4-SNAPSHOT</version>
</dependency>
</dependencies>
The integration can be enabled by setting
spring.cloud.vault.rabbitmq.enabled=true
(default false
) and providing the role name with spring.cloud.vault.rabbitmq.role=…
.
Username and password are stored in spring.rabbitmq.username
and spring.rabbitmq.password
so using Spring Boot will pick up the generated credentials without further configuration.
You can configure the property names by setting spring.cloud.vault.rabbitmq.username-property
and
spring.cloud.vault.rabbitmq.password-property
.
spring.cloud.vault:
rabbitmq:
enabled: true
role: readonly
backend: rabbitmq
username-property: spring.rabbitmq.username
password-property: spring.rabbitmq.password
-
enabled
setting this value totrue
enables the RabbitMQ backend config usage -
role
sets the role name of the RabbitMQ role definition -
backend
sets the path of the RabbitMQ mount to use -
username-property
sets the property name in which the RabbitMQ username is stored -
password-property
sets the property name in which the RabbitMQ password is stored
7.4. AWS
Spring Cloud Vault can obtain credentials for AWS.
The AWS integration requires the spring-cloud-vault-config-aws
dependency.
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-vault-config-aws</artifactId>
<version>3.1.4-SNAPSHOT</version>
</dependency>
</dependencies>
The integration can be enabled by setting
spring.cloud.vault.aws=true
(default false
) and providing the role name with spring.cloud.vault.aws.role=…
.
Supported AWS credential Types:
-
iam_user (Defaults)
-
assumed_role (STS)
-
federation_token (STS)
The access key and secret key are stored in cloud.aws.credentials.accessKey
and cloud.aws.credentials.secretKey
. So using Spring Cloud AWS will pick up the generated credentials without further configuration.
You can configure the property names by setting spring.cloud.vault.aws.access-key-property
and
spring.cloud.vault.aws.secret-key-property
.
For STS security token, you can configure the property name by setting spring.cloud.vault.aws.session-token-key-property
. The security token is stored under cloud.aws.credentials.sessionToken
(defaults).
Example: iam_user
spring.cloud.vault:
aws:
enabled: true
role: readonly
backend: aws
access-key-property: cloud.aws.credentials.accessKey
secret-key-property: cloud.aws.credentials.secretKey
Example: assumed_role (STS)
spring.cloud.vault:
aws:
enabled: true
role: sts-vault-role
backend: aws
credential-type: assumed_role
access-key-property: cloud.aws.credentials.accessKey
secret-key-property: cloud.aws.credentials.secretKey
session-token-key-property: cloud.aws.credentials.sessionToken
ttl: 3600s
role-arn: arn:aws:iam::${AWS_ACCOUNT}:role/sts-app-role
-
enabled
setting this value totrue
enables the AWS backend config usage -
role
sets the role name of the AWS role definition -
backend
sets the path of the AWS mount to use -
access-key-property
sets the property name in which the AWS access key is stored -
secret-key-property
sets the property name in which the AWS secret key is stored -
session-token-key-property
sets the property name in which the AWS STS security token is stored. -
credential-type
sets the aws credential type to use for this backend. Defaults toiam_user
-
ttl
sets the ttl for the STS token when usingassumed_role
orfederation_token
. Defaults to the ttl specified by the vault role. Min/Max values are also limited to what AWS would support for STS. -
role-arn
sets the IAM role to assume if more than one are configured for the vault role when usingassumed_role
.
8. Database backends
Vault supports several database secret backends to generate database credentials dynamically based on configured roles. This means services that need to access a database no longer need to configure credentials: they can request them from Vault, and use Vault’s leasing mechanism to more easily roll keys.
Spring Cloud Vault integrates with these backends:
Using a database secret backend requires to enable the backend in the configuration and the spring-cloud-vault-config-databases
dependency.
Vault ships since 0.7.1 with a dedicated database
secret backend that allows database integration via plugins.
You can use that specific backend by using the generic database backend.
Make sure to specify the appropriate backend path, e.g. spring.cloud.vault.mysql.role.backend=database
.
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-vault-config-databases</artifactId>
<version>3.1.4-SNAPSHOT</version>
</dependency>
</dependencies>
Enabling multiple JDBC-compliant databases will generate credentials and store them by default in the same property keys hence property names for JDBC secrets need to be configured separately. |
8.1. Database
Spring Cloud Vault can obtain credentials for any database listed at
www.vaultproject.io/api/secret/databases/index.html.
The integration can be enabled by setting
spring.cloud.vault.database.enabled=true
(default false
) and providing the role name with spring.cloud.vault.database.role=…
.
While the database backend is a generic one, spring.cloud.vault.database
specifically targets JDBC databases.
Username and password are available from spring.datasource.username
and spring.datasource.password
properties
so using Spring Boot will pick up the generated credentials for your DataSource
without further configuration.
You can configure the property names by setting
spring.cloud.vault.database.username-property
and
spring.cloud.vault.database.password-property
.
spring.cloud.vault:
database:
enabled: true
role: readonly
backend: database
username-property: spring.datasource.username
password-property: spring.datasource.password
8.2. Multiple Databases
Sometimes, credentials for a single database isn’t sufficient because an application might connect to two or more databases of the same kind.
Beginning with version 3.0.5, Spring Vault supports the configuration of multiple database secret backends under the spring.cloud.vault.databases.*
namespace.
The configuration accepts multiple database backends to materialize credentials into the specified properties. Make sure to configure username-property
and password-property
appropriately.
spring.cloud.vault:
databases:
primary:
enabled: true
role: readwrite
backend: database
username-property: spring.primary-datasource.username
password-property: spring.primary-datasource.password
other-database:
enabled: true
role: readonly
backend: database
username-property: spring.secondary-datasource.username
password-property: spring.secondary-datasource.password
-
<name>
descriptive name of the database configuration. -
<name>.enabled
setting this value totrue
enables the Database backend config usage -
<name>.role
sets the role name of the Database role definition -
<name>.backend
sets the path of the Database mount to use -
<name>.username-property
sets the property name in which the Database username is stored. Make sure to use unique property names to avoid property shadowing. -
<name>.password-property
sets the property name in which the Database password is stored Make sure to use unique property names to avoid property shadowing.
Spring Cloud Vault does not support getting new credentials and configuring your DataSource with them when the maximum lease time has been reached.
That is, if max_ttl of the Database role in Vault is set to 24h that means that 24 hours after your application has started it can no longer authenticate with the database.
|
8.3. Apache Cassandra
The cassandra backend has been deprecated in Vault 0.7.1 and it is recommended to use the database backend and mount it as cassandra .
|
Spring Cloud Vault can obtain credentials for Apache Cassandra.
The integration can be enabled by setting
spring.cloud.vault.cassandra.enabled=true
(default false
) and providing the role name with spring.cloud.vault.cassandra.role=…
.
Username and password are available from spring.data.cassandra.username
and spring.data.cassandra.password
properties so using Spring Boot will pick up the generated credentials without further configuration.
You can configure the property names by setting
spring.cloud.vault.cassandra.username-property
and
spring.cloud.vault.cassandra.password-property
.
spring.cloud.vault:
cassandra:
enabled: true
role: readonly
backend: cassandra
username-property: spring.data.cassandra.username
password-property: spring.data.cassandra.password
-
enabled
setting this value totrue
enables the Cassandra backend config usage -
role
sets the role name of the Cassandra role definition -
backend
sets the path of the Cassandra mount to use -
username-property
sets the property name in which the Cassandra username is stored -
password-property
sets the property name in which the Cassandra password is stored
8.4. Couchbase Database
Spring Cloud Vault can obtain credentials for Couchbase.
The integration can be enabled by setting
spring.cloud.vault.couchbase.enabled=true
(default false
) and providing the role name with spring.cloud.vault.couchbase.role=…
.
Username and password are available from spring.couchbase.username
and spring.couchbase.password
properties so using Spring Boot will pick up the generated credentials without further configuration.
You can configure the property names by setting
spring.cloud.vault.couchbase.username-property
and
spring.cloud.vault.couchbase.password-property
.
spring.cloud.vault:
couchbase:
enabled: true
role: readonly
backend: database
username-property: spring.couchbase.username
password-property: spring.couchbase.password
-
enabled
setting this value totrue
enables the Couchbase backend config usage -
role
sets the role name of the Couchbase role definition -
backend
sets the path of the Couchbase mount to use -
username-property
sets the property name in which the Couchbase username is stored -
password-property
sets the property name in which the Couchbase password is stored
See also: Couchbase Database Plugin Documentation
8.5. Elasticsearch
Spring Cloud Vault can obtain since version 3.0 credentials for Elasticsearch.
The integration can be enabled by setting
spring.cloud.vault.elasticsearch.enabled=true
(default false
) and providing the role name with spring.cloud.vault.elasticsearch.role=…
.
Username and password are available from spring.elasticsearch.rest.username
and spring.elasticsearch.rest.password
properties so using Spring Boot will pick up the generated credentials without further configuration.
You can configure the property names by setting
spring.cloud.vault.elasticsearch.username-property
and
spring.cloud.vault.elasticsearch.password-property
.
spring.cloud.vault:
elasticsearch:
enabled: true
role: readonly
backend: mongodb
username-property: spring.elasticsearch.rest.username
password-property: spring.elasticsearch.rest.password
-
enabled
setting this value totrue
enables the Elasticsearch database backend config usage -
role
sets the role name of the Elasticsearch role definition -
backend
sets the path of the Elasticsearch mount to use -
username-property
sets the property name in which the Elasticsearch username is stored -
password-property
sets the property name in which the Elasticsearch password is stored
8.6. MongoDB
The mongodb backend has been deprecated in Vault 0.7.1 and it is recommended to use the database backend and mount it as mongodb .
|
Spring Cloud Vault can obtain credentials for MongoDB.
The integration can be enabled by setting
spring.cloud.vault.mongodb.enabled=true
(default false
) and providing the role name with spring.cloud.vault.mongodb.role=…
.
Username and password are stored in spring.data.mongodb.username
and spring.data.mongodb.password
so using Spring Boot will pick up the generated credentials without further configuration.
You can configure the property names by setting
spring.cloud.vault.mongodb.username-property
and
spring.cloud.vault.mongodb.password-property
.
spring.cloud.vault:
mongodb:
enabled: true
role: readonly
backend: mongodb
username-property: spring.data.mongodb.username
password-property: spring.data.mongodb.password
-
enabled
setting this value totrue
enables the MongodB backend config usage -
role
sets the role name of the MongoDB role definition -
backend
sets the path of the MongoDB mount to use -
username-property
sets the property name in which the MongoDB username is stored -
password-property
sets the property name in which the MongoDB password is stored
8.7. MySQL
The mysql backend has been deprecated in Vault 0.7.1 and it is recommended to use the database backend and mount it as mysql .
Configuration for spring.cloud.vault.mysql will be removed in a future version.
|
Spring Cloud Vault can obtain credentials for MySQL.
The integration can be enabled by setting
spring.cloud.vault.mysql.enabled=true
(default false
) and providing the role name with spring.cloud.vault.mysql.role=…
.
Username and password are available from spring.datasource.username
and spring.datasource.password
properties so using Spring Boot will pick up the generated credentials without further configuration.
You can configure the property names by setting
spring.cloud.vault.mysql.username-property
and
spring.cloud.vault.mysql.password-property
.
spring.cloud.vault:
mysql:
enabled: true
role: readonly
backend: mysql
username-property: spring.datasource.username
password-property: spring.datasource.password
-
enabled
setting this value totrue
enables the MySQL backend config usage -
role
sets the role name of the MySQL role definition -
backend
sets the path of the MySQL mount to use -
username-property
sets the property name in which the MySQL username is stored -
password-property
sets the property name in which the MySQL password is stored
8.8. PostgreSQL
The postgresql backend has been deprecated in Vault 0.7.1 and it is recommended to use the database backend and mount it as postgresql .
Configuration for spring.cloud.vault.postgresql will be removed in a future version.
|
Spring Cloud Vault can obtain credentials for PostgreSQL.
The integration can be enabled by setting
spring.cloud.vault.postgresql.enabled=true
(default false
) and providing the role name with spring.cloud.vault.postgresql.role=…
.
Username and password are available from spring.datasource.username
and spring.datasource.password
properties so using Spring Boot will pick up the generated credentials without further configuration.
You can configure the property names by setting
spring.cloud.vault.postgresql.username-property
and
spring.cloud.vault.postgresql.password-property
.
spring.cloud.vault:
postgresql:
enabled: true
role: readonly
backend: postgresql
username-property: spring.datasource.username
password-property: spring.datasource.password
-
enabled
setting this value totrue
enables the PostgreSQL backend config usage -
role
sets the role name of the PostgreSQL role definition -
backend
sets the path of the PostgreSQL mount to use -
username-property
sets the property name in which the PostgreSQL username is stored -
password-property
sets the property name in which the PostgreSQL password is stored
9. Customize which secret backends to expose as PropertySource
Spring Cloud Vault uses property-based configuration to create PropertySource
s for key-value and discovered secret backends.
Discovered backends provide VaultSecretBackendDescriptor
beans to describe the configuration state to use secret backend as PropertySource
.
A SecretBackendMetadataFactory
is required to create a SecretBackendMetadata
object which contains path, name and property transformation configuration.
SecretBackendMetadata
is used to back a particular PropertySource
.
You can register a VaultConfigurer
for customization.
Default key-value and discovered backend registration is disabled if you provide a VaultConfigurer
.
You can however enable default registration with
SecretBackendConfigurer.registerDefaultKeyValueSecretBackends()
and SecretBackendConfigurer.registerDefaultDiscoveredSecretBackends()
.
public class CustomizationBean implements VaultConfigurer {
@Override
public void addSecretBackends(SecretBackendConfigurer configurer) {
configurer.add("secret/my-application");
configurer.registerDefaultKeyValueSecretBackends(false);
configurer.registerDefaultDiscoveredSecretBackends(true);
}
}
SpringApplication application = new SpringApplication(MyApplication.class);
application.addBootstrapper(VaultBootstrapper.fromConfigurer(new CustomizationBean()));
10. Custom Secret Backend Implementations
Spring Cloud Vault ships with secret backend support for the most common backend integrations.
You can integrate with any kind of backend by providing an implementation that describes how to obtain data from the backend you want to use and how to surface data provided by that backend by providing a PropertyTransformer
.
Adding a custom implementation for a backend requires implementation of two interfaces:
-
org.springframework.cloud.vault.config.VaultSecretBackendDescriptor
-
org.springframework.cloud.vault.config.SecretBackendMetadataFactory
VaultSecretBackendDescriptor
is typically an object that holds configuration data, such as VaultDatabaseProperties
. Spring Cloud Vault requires that your type is annotated with @ConfigurationProperties
to materialize the class from the configuration.
SecretBackendMetadataFactory
accepts VaultSecretBackendDescriptor
to create the actual SecretBackendMetadata
object which holds the context path within your Vault server, any path variables required to resolve parametrized context paths and PropertyTransformer
.
Both, VaultSecretBackendDescriptor
and SecretBackendMetadataFactory
types must be registered in spring.factories
which is an extension mechanism provided by Spring, similar to Java’s ServiceLoader.
11. Service Registry Configuration
You can use a DiscoveryClient
(such as from Spring Cloud Consul) to locate a Vault server by setting spring.cloud.vault.discovery.enabled=true (default false
).
The net result of that is that your apps need a application.yml (or an environment variable) with the appropriate discovery configuration.
The benefit is that the Vault can change its co-ordinates, as long as the discovery service is a fixed point.
The default service id is vault
but you can change that on the client with
spring.cloud.vault.discovery.serviceId
.
The discovery client implementations all support some kind of metadata map (e.g. for Eureka we have eureka.instance.metadataMap).
Some additional properties of the service may need to be configured in its service registration metadata so that clients can connect correctly.
Service registries that do not provide details about transport layer security need to provide a scheme
metadata entry to be set either to https
or http
.
If no scheme is configured and the service is not exposed as secure service, then configuration defaults to spring.cloud.vault.scheme
which is https
when it’s not set.
spring.cloud.vault.discovery:
enabled: true
service-id: my-vault-service
12. Vault Client Fail Fast
In some cases, it may be desirable to fail startup of a service if it cannot connect to the Vault Server.
If this is the desired behavior, set the bootstrap configuration property
spring.cloud.vault.fail-fast=true
and the client will halt with an Exception.
spring.cloud.vault:
fail-fast: true
13. Vault Enterprise Namespace Support
Vault Enterprise allows using namespaces to isolate multiple Vaults on a single Vault server.
Configuring a namespace by setting
spring.cloud.vault.namespace=…
enables the namespace header
X-Vault-Namespace
on every outgoing HTTP request when using the Vault
RestTemplate
or WebClient
.
Please note that this feature is not supported by Vault Community edition and has no effect on Vault operations.
spring.cloud.vault:
namespace: my-namespace
See also: Vault Enterprise: Namespaces
14. Vault Client SSL configuration
SSL can be configured declaratively by setting various properties.
You can set either javax.net.ssl.trustStore
to configure JVM-wide SSL settings or spring.cloud.vault.ssl.trust-store
to set SSL settings only for Spring Cloud Vault Config.
spring.cloud.vault:
ssl:
trust-store: classpath:keystore.jks
trust-store-password: changeit
trust-store-type: JKS
enabled-protocols: TLSv1.2,TLSv1.3
enabled-cipher-suites: TLS_AES_128_GCM_SHA256
-
trust-store
sets the resource for the trust-store. SSL-secured Vault communication will validate the Vault SSL certificate with the specified trust-store. -
trust-store-password
sets the trust-store password -
trust-store-type
sets the trust-store type. Supported values are all supportedKeyStore
types includingPEM
. -
enabled-protocols
sets the list of enabled SSL/TLS protocols (since 3.0.2). -
enabled-cipher-suites
sets the list of enabled SSL/TLS cipher suites (since 3.0.2).
Please note that configuring spring.cloud.vault.ssl.*
can be only applied when either Apache Http Components or the OkHttp client is on your class-path.
15. Lease lifecycle management (renewal and revocation)
With every secret, Vault creates a lease: metadata containing information such as a time duration, renewability, and more.
Vault promises that the data will be valid for the given duration, or Time To Live (TTL). Once the lease is expired, Vault can revoke the data, and the consumer of the secret can no longer be certain that it is valid.
Spring Cloud Vault maintains a lease lifecycle beyond the creation of login tokens and secrets. That said, login tokens and secrets associated with a lease are scheduled for renewal just before the lease expires until terminal expiry. Application shutdown revokes obtained login tokens and renewable leases.
Secret service and database backends (such as MongoDB or MySQL) usually generate a renewable lease so generated credentials will be disabled on application shutdown.
Static tokens are not renewed or revoked. |
Lease renewal and revocation is enabled by default and can be disabled by setting spring.cloud.vault.config.lifecycle.enabled
to false
.
This is not recommended as leases can expire and Spring Cloud Vault cannot longer access Vault or services using generated credentials and valid credentials remain active after application shutdown.
spring.cloud.vault:
config.lifecycle:
enabled: true
min-renewal: 10s
expiry-threshold: 1m
lease-endpoints: Legacy
-
enabled
controls whether leases associated with secrets are considered to be renewed and expired secrets are rotated. Enabled by default. -
min-renewal
sets the duration that is at least required before renewing a lease. This setting prevents renewals from happening too often. -
expiry-threshold
sets the expiry threshold. A lease is renewed the configured period of time before it expires. -
lease-endpoints
sets the endpoints for renew and revoke. Legacy for vault versions before 0.8 and SysLeases for later.
16. Session token lifecycle management (renewal, re-login and revocation)
A Vault session token (also referred to as LoginToken
) is quite similar to a lease as it has a TTL, max TTL, and may expire.
Once a login token expires, it cannot be used anymore to interact with Vault.
Therefore, Spring Vault ships with a SessionManager
API for imperative and reactive use.
Spring Cloud Vault maintains the session token lifecycle by default. Session tokens are obtained lazily so the actual login is deferred until the first session-bound use of Vault. Once Spring Cloud Vault obtains a session token, it retains it until expiry. The next time a session-bound activity is used, Spring Cloud Vault re-logins into Vault and obtains a new session token. On application shut down, Spring Cloud Vault revokes the token if it was still active to terminate the session.
Session lifecycle is enabled by default and can be disabled by setting spring.cloud.vault.session.lifecycle.enabled
to false
.
Disabling is not recommended as session tokens can expire and Spring Cloud Vault cannot longer access Vault.
spring.cloud.vault:
session.lifecycle:
enabled: true
refresh-before-expiry: 10s
expiry-threshold: 20s
-
enabled
controls whether session lifecycle management is enabled to renew session tokens. Enabled by default. -
refresh-before-expiry
controls the point in time when the session token gets renewed. The refresh time is calculated by subtractingrefresh-before-expiry
from the token expiry time. Defaults to5 seconds
. -
expiry-threshold
sets the expiry threshold. The threshold represents a minimum TTL duration to consider a session token as valid. Tokens with a shorter TTL are considered expired and are not used anymore. Should be greater thanrefresh-before-expiry
to prevent token expiry. Defaults to7 seconds
.
See also: Vault Documentation: Token Renewal
Appendix A: Common application properties
Various properties can be specified inside your application.properties
file, inside your application.yml
file, or as command line switches.
This appendix provides a list of common Spring Cloud Vault properties and references to the underlying classes that consume them.
Property contributions can come from additional jar files on your classpath, so you should not consider this an exhaustive list. Also, you can define your own properties. |
Name | Default | Description |
---|---|---|
spring.cloud.vault.app-id.app-id-path |
|
Mount path of the AppId authentication backend. |
spring.cloud.vault.app-id.network-interface |
Network interface hint for the "MAC_ADDRESS" UserId mechanism. |
|
spring.cloud.vault.app-id.user-id |
|
UserId mechanism. Can be either "MAC_ADDRESS", "IP_ADDRESS", a string or a class name. |
spring.cloud.vault.app-role.app-role-path |
|
Mount path of the AppRole authentication backend. |
spring.cloud.vault.app-role.role |
Name of the role, optional, used for pull-mode. |
|
spring.cloud.vault.app-role.role-id |
The RoleId. |
|
spring.cloud.vault.app-role.secret-id |
The SecretId. |
|
spring.cloud.vault.application-name |
|
Application name for AppId authentication. |
spring.cloud.vault.authentication |
||
spring.cloud.vault.aws-ec2.aws-ec2-path |
|
Mount path of the AWS-EC2 authentication backend. |
spring.cloud.vault.aws-ec2.identity-document |
|
URL of the AWS-EC2 PKCS7 identity document. |
spring.cloud.vault.aws-ec2.nonce |
Nonce used for AWS-EC2 authentication. An empty nonce defaults to nonce generation. |
|
spring.cloud.vault.aws-ec2.role |
Name of the role, optional. |
|
spring.cloud.vault.aws-iam.aws-path |
|
Mount path of the AWS authentication backend. |
spring.cloud.vault.aws-iam.endpoint-uri |
STS server URI. @since 2.2 |
|
spring.cloud.vault.aws-iam.role |
Name of the role, optional. Defaults to the friendly IAM name if not set. |
|
spring.cloud.vault.aws-iam.server-name |
Name of the server used to set {@code X-Vault-AWS-IAM-Server-ID} header in the headers of login requests. |
|
spring.cloud.vault.aws.access-key-property |
|
Target property for the obtained access key. |
spring.cloud.vault.aws.backend |
|
aws backend path. |
spring.cloud.vault.aws.credential-type |
aws credential type |
|
spring.cloud.vault.aws.enabled |
|
Enable aws backend usage. |
spring.cloud.vault.aws.role |
Role name for credentials. |
|
spring.cloud.vault.aws.role-arn |
Role arn for assumed_role in case we have multiple roles associated with the vault role. @since 3.0.2 |
|
spring.cloud.vault.aws.secret-key-property |
|
Target property for the obtained secret key. |
spring.cloud.vault.aws.session-token-key-property |
|
Target property for the obtained secret key. |
spring.cloud.vault.aws.ttl |
|
TTL for sts tokens. Defaults to whatever the vault Role may have for Max. Also limited to what AWS supports to be the max for STS. @since 3.0.2 |
spring.cloud.vault.azure-msi.azure-path |
|
Mount path of the Azure MSI authentication backend. |
spring.cloud.vault.azure-msi.identity-token-service |
Identity token service URI. @since 3.0 |
|
spring.cloud.vault.azure-msi.metadata-service |
Instance metadata service URI. @since 3.0 |
|
spring.cloud.vault.azure-msi.role |
Name of the role. |
|
spring.cloud.vault.cassandra.backend |
|
Cassandra backend path. |
spring.cloud.vault.cassandra.enabled |
|
Enable cassandra backend usage. |
spring.cloud.vault.cassandra.password-property |
|
Target property for the obtained password. |
spring.cloud.vault.cassandra.role |
Role name for credentials. |
|
spring.cloud.vault.cassandra.static-role |
|
Enable static role usage. @since 2.2 |
spring.cloud.vault.cassandra.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.config.lifecycle.enabled |
|
Enable lifecycle management. |
spring.cloud.vault.config.lifecycle.expiry-threshold |
The expiry threshold. {@link Lease} is renewed the given {@link Duration} before it expires. @since 2.2 |
|
spring.cloud.vault.config.lifecycle.lease-endpoints |
Set the {@link LeaseEndpoints} to delegate renewal/revocation calls to. {@link LeaseEndpoints} encapsulates differences between Vault versions that affect the location of renewal/revocation endpoints. Can be {@link LeaseEndpoints#SysLeases} for version 0.8 or above of Vault or {@link LeaseEndpoints#Legacy} for older versions (the default). @since 2.2 |
|
spring.cloud.vault.config.lifecycle.min-renewal |
The time period that is at least required before renewing a lease. @since 2.2 |
|
spring.cloud.vault.config.order |
|
Used to set a {@link org.springframework.core.env.PropertySource} priority. This is useful to use Vault as an override on other property sources. @see org.springframework.core.PriorityOrdered |
spring.cloud.vault.connection-timeout |
|
Connection timeout. |
spring.cloud.vault.consul.backend |
|
Consul backend path. |
spring.cloud.vault.consul.enabled |
|
Enable consul backend usage. |
spring.cloud.vault.consul.role |
Role name for credentials. |
|
spring.cloud.vault.consul.token-property |
|
Target property for the obtained token. |
spring.cloud.vault.couchbase.backend |
|
Couchbase backend path. |
spring.cloud.vault.couchbase.enabled |
|
Enable couchbase backend usage. |
spring.cloud.vault.couchbase.password-property |
|
Target property for the obtained password. |
spring.cloud.vault.couchbase.role |
Role name for credentials. |
|
spring.cloud.vault.couchbase.static-role |
|
Enable static role usage. |
spring.cloud.vault.couchbase.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.database.backend |
|
Database backend path. |
spring.cloud.vault.database.enabled |
|
Enable database backend usage. |
spring.cloud.vault.database.password-property |
|
Target property for the obtained password. |
spring.cloud.vault.database.role |
Role name for credentials. |
|
spring.cloud.vault.database.static-role |
|
Enable static role usage. |
spring.cloud.vault.database.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.databases |
||
spring.cloud.vault.discovery.enabled |
|
Flag to indicate that Vault server discovery is enabled (vault server URL will be looked up via discovery). |
spring.cloud.vault.discovery.service-id |
|
Service id to locate Vault. |
spring.cloud.vault.elasticsearch.backend |
|
Database backend path. |
spring.cloud.vault.elasticsearch.enabled |
|
Enable elasticsearch backend usage. |
spring.cloud.vault.elasticsearch.password-property |
|
Target property for the obtained password. |
spring.cloud.vault.elasticsearch.role |
Role name for credentials. |
|
spring.cloud.vault.elasticsearch.static-role |
|
Enable static role usage. |
spring.cloud.vault.elasticsearch.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.enabled |
|
Enable Vault config server. |
spring.cloud.vault.fail-fast |
|
Fail fast if data cannot be obtained from Vault. |
spring.cloud.vault.gcp-gce.gcp-path |
|
Mount path of the Kubernetes authentication backend. |
spring.cloud.vault.gcp-gce.role |
Name of the role against which the login is being attempted. |
|
spring.cloud.vault.gcp-gce.service-account |
Optional service account id. Using the default id if left unconfigured. |
|
spring.cloud.vault.gcp-iam.credentials.encoded-key |
The base64 encoded contents of an OAuth2 account private key in JSON format. |
|
spring.cloud.vault.gcp-iam.credentials.location |
Location of the OAuth2 credentials private key. <p> Since this is a Resource, the private key can be in a multitude of locations, such as a local file system, classpath, URL, etc. |
|
spring.cloud.vault.gcp-iam.gcp-path |
|
Mount path of the Kubernetes authentication backend. |
spring.cloud.vault.gcp-iam.jwt-validity |
|
Validity of the JWT token. |
spring.cloud.vault.gcp-iam.project-id |
Overrides the GCP project Id. |
|
spring.cloud.vault.gcp-iam.role |
Name of the role against which the login is being attempted. |
|
spring.cloud.vault.gcp-iam.service-account-id |
Overrides the GCP service account Id. |
|
spring.cloud.vault.host |
|
Vault server host. |
spring.cloud.vault.kubernetes.kubernetes-path |
|
Mount path of the Kubernetes authentication backend. |
spring.cloud.vault.kubernetes.role |
Name of the role against which the login is being attempted. |
|
spring.cloud.vault.kubernetes.service-account-token-file |
|
Path to the service account token file. |
spring.cloud.vault.kv.application-name |
|
Application name to be used for the context. |
spring.cloud.vault.kv.backend |
|
Name of the default backend. |
spring.cloud.vault.kv.backend-version |
|
Key-Value backend version. Currently supported versions are: <ul> <li>Version 1 (unversioned key-value backend).</li> <li>Version 2 (versioned key-value backend).</li> </ul> |
spring.cloud.vault.kv.default-context |
|
Name of the default context. |
spring.cloud.vault.kv.enabled |
|
Enable the key-value backend. |
spring.cloud.vault.kv.profile-separator |
|
Profile-separator to combine application name and profile. |
spring.cloud.vault.kv.profiles |
List of active profiles. @since 3.0 |
|
spring.cloud.vault.mongodb.backend |
|
MongoDB backend path. |
spring.cloud.vault.mongodb.enabled |
|
Enable mongodb backend usage. |
spring.cloud.vault.mongodb.password-property |
|
Target property for the obtained password. |
spring.cloud.vault.mongodb.role |
Role name for credentials. |
|
spring.cloud.vault.mongodb.static-role |
|
Enable static role usage. @since 2.2 |
spring.cloud.vault.mongodb.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.mysql.backend |
|
mysql backend path. |
spring.cloud.vault.mysql.enabled |
|
Enable mysql backend usage. |
spring.cloud.vault.mysql.password-property |
|
Target property for the obtained username. |
spring.cloud.vault.mysql.role |
Role name for credentials. |
|
spring.cloud.vault.mysql.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.namespace |
Vault namespace (requires Vault Enterprise). |
|
spring.cloud.vault.pcf.instance-certificate |
Path to the instance certificate (PEM). Defaults to {@code CF_INSTANCE_CERT} env variable. |
|
spring.cloud.vault.pcf.instance-key |
Path to the instance key (PEM). Defaults to {@code CF_INSTANCE_KEY} env variable. |
|
spring.cloud.vault.pcf.pcf-path |
|
Mount path of the Kubernetes authentication backend. |
spring.cloud.vault.pcf.role |
Name of the role against which the login is being attempted. |
|
spring.cloud.vault.port |
|
Vault server port. |
spring.cloud.vault.postgresql.backend |
|
postgresql backend path. |
spring.cloud.vault.postgresql.enabled |
|
Enable postgresql backend usage. |
spring.cloud.vault.postgresql.password-property |
|
Target property for the obtained username. |
spring.cloud.vault.postgresql.role |
Role name for credentials. |
|
spring.cloud.vault.postgresql.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.rabbitmq.backend |
|
rabbitmq backend path. |
spring.cloud.vault.rabbitmq.enabled |
|
Enable rabbitmq backend usage. |
spring.cloud.vault.rabbitmq.password-property |
|
Target property for the obtained password. |
spring.cloud.vault.rabbitmq.role |
Role name for credentials. |
|
spring.cloud.vault.rabbitmq.username-property |
|
Target property for the obtained username. |
spring.cloud.vault.reactive.enabled |
|
Flag to indicate that reactive discovery is enabled |
spring.cloud.vault.read-timeout |
|
Read timeout. |
spring.cloud.vault.scheme |
|
Protocol scheme. Can be either "http" or "https". |
spring.cloud.vault.session.lifecycle.enabled |
|
Enable session lifecycle management. |
spring.cloud.vault.session.lifecycle.expiry-threshold |
|
The expiry threshold for a {@link LoginToken}. The threshold represents a minimum TTL duration to consider a login token as valid. Tokens with a shorter TTL are considered expired and are not used anymore. Should be greater than {@code refreshBeforeExpiry} to prevent token expiry. |
spring.cloud.vault.session.lifecycle.refresh-before-expiry |
|
The time period that is at least required before renewing the {@link LoginToken}. |
spring.cloud.vault.ssl.cert-auth-path |
|
Mount path of the TLS cert authentication backend. |
spring.cloud.vault.ssl.enabled-cipher-suites |
List of enabled SSL/TLS cipher suites. @since 3.0.2 |
|
spring.cloud.vault.ssl.enabled-protocols |
List of enabled SSL/TLS protocol. @since 3.0.2 |
|
spring.cloud.vault.ssl.key-store |
Trust store that holds certificates and private keys. |
|
spring.cloud.vault.ssl.key-store-password |
Password used to access the key store. |
|
spring.cloud.vault.ssl.key-store-type |
Type of the key store. @since 3.0 |
|
spring.cloud.vault.ssl.trust-store |
Trust store that holds SSL certificates. |
|
spring.cloud.vault.ssl.trust-store-password |
Password used to access the trust store. |
|
spring.cloud.vault.ssl.trust-store-type |
Type of the trust store. @since 3.0 |
|
spring.cloud.vault.token |
Static vault token. Required if {@link #authentication} is {@code TOKEN}. |
|
spring.cloud.vault.uri |
Vault URI. Can be set with scheme, host and port. |