This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Cloud Vault 4.2.0! |
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.
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:
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
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.
|
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;
}
}
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 |
|
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.
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
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:
region: aws-global
role: my-dev-role
aws-path: aws
server-name: some.server.name
endpoint-uri: https://sts.eu-central-1.amazonaws.com
-
region
sets the name of the AWS region. If not supplied, the region will be determined by AWS defaults. -
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 v2 dependency (software.amazon.awssdk:auth
) as the authentication implementation uses AWS SDK types for credentials and request signing.
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:
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
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:
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:
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:
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:
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. |
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 |
|