OpenID Connect (OIDC) Authentication Using ID Tokens (FREE)

You can authenticate with third party services using GitLab CI/CD's ID tokens.

ID Tokens

ID tokens are JSON Web Tokens (JWTs) that can be added to a GitLab CI/CD job. They can be used for OIDC authentication with third-party services, and are used by the secrets keyword to authenticate with HashiCorp Vault.

ID tokens are configured in the .gitlab-ci.yml. For example:

job_with_id_tokens:
  id_tokens:
    FIRST_ID_TOKEN:
      aud: https://first.service.com
    SECOND_ID_TOKEN:
      aud: https://second.service.com
  script:
    - first-service-authentication-script.sh $FIRST_ID_TOKEN
    - second-service-authentication-script.sh $SECOND_ID_TOKEN

In this example, the two tokens have different aud claims. Third party services can be configured to reject tokens that do not have an aud claim matching their bound audience. Use this functionality to reduce the number of services with which a token can authenticate. This reduces the severity of having a token compromised.

Token payload

The following standard claims are included in each ID token:

Field	Description
`iss`	Issuer of the token, which is the domain of the GitLab instance ("issuer" claim).
`sub`	`project_path:{group}/{project}:ref_type:{type}:ref:{branch_name}` ("subject" claim).
`aud`	Intended audience for the token ("audience" claim). Specified in the ID tokens configuration. The domain of the GitLab instance by default.
`exp`	The expiration time ("expiration time" claim).
`nbf`	The time after which the token becomes valid ("not before" claim).
`iat`	The time the JWT was issued ("issued at" claim).
`jti`	Unique identifier for the token ("JWT ID" claim).

The token also includes custom claims provided by GitLab:

Field	When	Description
`namespace_id`	Always	Use this to scope to group or user level namespace by ID.
`namespace_path`	Always	Use this to scope to group or user level namespace by path.
`project_id`	Always	Use this to scope to project by ID.
`project_path`	Always	Use this to scope to project by path.
`user_id`	Always	ID of the user executing the job.
`user_login`	Always	Username of the user executing the job.
`user_email`	Always	Email of the user executing the job.
`pipeline_id`	Always	ID of the pipeline.
`pipeline_source`	Always	Pipeline source.
`job_id`	Always	ID of the job.
`ref`	Always	Git ref for the job.
`ref_type`	Always	Git ref type, either `branch` or `tag`.
`ref_protected`	Always	`true` if the Git ref is protected, `false` otherwise.
`environment`	Job specifies an environment	Environment this job deploys to (introduced in GitLab 13.9).
`environment_protected`	Job specifies an environment	`true` if deployed environment is protected, `false` otherwise (introduced in GitLab 13.9).
`deployment_tier`	Job specifies an environment	Deployment tier of the environment the job specifies. Introduced in GitLab 15.2.

{
  "namespace_id": "72",
  "namespace_path": "my-group",
  "project_id": "20",
  "project_path": "my-group/my-project",
  "user_id": "1",
  "user_login": "sample-user",
  "user_email": "sample-user@example.com",
  "pipeline_id": "574",
  "pipeline_source": "push",
  "job_id": "302",
  "ref": "feature-branch-1",
  "ref_type": "branch",
  "ref_protected": "false",
  "environment": "test-environment2",
  "environment_protected": "false",
  "deployment_tier": "testing",
  "jti": "235b3a54-b797-45c7-ae9a-f72d7bc6ef5b",
  "iss": "https://gitlab.example.com",
  "iat": 1681395193,
  "nbf": 1681395188,
  "exp": 1681398793,
  "sub": "project_path:my-group/my-project:ref_type:branch:ref:feature-branch-1",
  "aud": "https://vault.example.com"
}

The ID token is encoded by using RS256 and signed with a dedicated private key. The expiry time for the token is set to the job's timeout if specified, or 5 minutes if no timeout is specified.

Manual ID Token authentication

You can use ID tokens for OIDC authentication with a third party service. For example:

manual_authentication:
  variables:
    VAULT_ADDR: http://vault.example.com:8200
  image: vault:latest
  id_tokens:
    VAULT_ID_TOKEN:
      aud: http://vault.example.com:8200
  script:
    - export VAULT_TOKEN="$(vault write -field=token auth/jwt/login role=myproject-example jwt=$VAULT_ID_TOKEN)"
    - export PASSWORD="$(vault kv get -field=password secret/myproject/example/db)"
    - my-authentication-script.sh $VAULT_TOKEN $PASSWORD

Automatic ID Token authentication with HashiCorp Vault (PREMIUM)

You can use ID tokens to automatically fetch secrets from HashiCorp Vault with the secrets keyword.

Enable automatic ID token authentication

To enable automatic ID token authentication:

On the top bar, select Main menu > Projects and find your project.
On the left sidebar, select Settings > CI/CD.
Expand Token Access.
Toggle Limit JSON Web Token (JWT) access to enabled.

Configure automatic ID Token authentication

If one ID token is defined, the secrets keyword automatically uses it to authenticate with Vault. For example:

job_with_secrets:
  id_tokens:
    VAULT_ID_TOKEN:
      aud: https://example.vault.com
  secrets:
    PROD_DB_PASSWORD:
      vault: example/db/password # authenticates using $VAULT_ID_TOKEN
  script:
    - access-prod-db.sh --token $PROD_DB_PASSWORD

If more than one ID token is defined, use the token keyword to specify which token should be used. For example:

job_with_secrets:
  id_tokens:
    FIRST_ID_TOKEN:
      aud: https://first.service.com
    SECOND_ID_TOKEN:
      aud: https://second.service.com
  secrets:
    FIRST_DB_PASSWORD:
      vault: first/db/password
      token: $FIRST_ID_TOKEN
    SECOND_DB_PASSWORD:
      vault: second/db/password
      token: $SECOND_ID_TOKEN
  script:
    - access-first-db.sh --token $FIRST_DB_PASSWORD
    - access-second-db.sh --token $SECOND_DB_PASSWORD