--- layout: docs page_title: OIDC Auth Method description: >- The OIDC auth method can be used to authenticate with Consul using OpenID Connect (OIDC). This method allows authentication via a configured OIDC provider using the user's web browser. This method may be initiated from the Consul UI or the command line. --- # OIDC Auth Method This feature is available in [Consul Enterprise](https://www.hashicorp.com/products/consul/) version 1.8.0 and newer. The `oidc` auth method can be used to authenticate with Consul using [OIDC](https://en.wikipedia.org/wiki/OpenID_Connect). This method allows authentication via a configured OIDC provider using the user's web browser. This method may be initiated from the Consul UI or the command line. This page assumes general knowledge of [OIDC concepts](https://developer.okta.com/blog/2017/07/25/oidc-primer-part-1) and the concepts described in the main [auth method documentation](/docs/acl/auth-methods). Both the [`jwt`](/docs/acl/auth-methods/jwt) and the [`oidc`](/docs/acl/auth-methods/oidc) auth method types allow additional processing of the claims data in the JWT. @include 'jwt_or_oidc.mdx' ## Config Parameters The following auth method [`Config`](/api/acl/auth-methods#config) parameters are required to properly configure an auth method of type `oidc`: - `OIDCDiscoveryURL` `(string: )` - The OIDC Discovery URL, without any .well-known component (base path). - `OIDCDiscoveryCACert` `(string: "")` - PEM encoded CA cert for use by the TLS client used to talk with the OIDC Discovery URL. NOTE: Every line must end with a newline (`\n`). If not set, system certificates are used. - `OIDCClientID` `(string: )` - The OAuth Client ID configured with your OIDC provider. - `OIDCClientSecret` `(string: )` - The OAuth Client Secret configured with your OIDC provider. - `AllowedRedirectURIs` `(array)` - A list of allowed values for `redirect_uri`. Must be non-empty. - `ClaimMappings` `(map[string]string)` - Mappings of claims (key) that [will be copied to a metadata field](#trusted-identity-attributes-via-claim-mappings) (value). Use this if the claim you are capturing is singular (such as an attribute). When mapped, the values can be any of a number, string, or boolean and will all be stringified when returned. - `ListClaimMappings` `(map[string]string)` - Mappings of claims (key) [will be copied to a metadata field](#trusted-identity-attributes-via-claim-mappings) (value). Use this if the claim you are capturing is list-like (such as groups). When mapped, the values in each list can be any of a number, string, or boolean and will all be stringified when returned. - `OIDCScopes` `(array)` - A list of OIDC scopes. - `JWTSupportedAlgs` `(array)` - JWTSupportedAlgs is a list of supported signing algorithms. Defaults to `RS256`. ([Available algorithms](https://github.com/hashicorp/consul/blob/main/vendor/github.com/coreos/go-oidc/jose.go#L7)) - `BoundAudiences` `(array)` - List of `aud` claims that are valid for login; any match is sufficient. - `VerboseOIDCLogging` `(bool: false)` - Log received OIDC tokens and claims when debug-level logging is active. Not recommended in production since sensitive information may be present in OIDC responses. ### Sample Config ```json { ...other fields... "Config": { "AllowedRedirectURIs": [ "http://localhost:8550/oidc/callback", "http://localhost:8500/ui/oidc/callback" ], "BoundAudiences": [ "V1RPi2MYptMV1RPi2MYptMV1RPi2MYpt" ], "ClaimMappings": { "http://example.com/first_name": "first_name", "http://example.com/last_name": "last_name" }, "ListClaimMappings": { "http://consul.com/groups": "groups" }, "OIDCClientID": "V1RPi2MYptMV1RPi2MYptMV1RPi2MYpt", "OIDCClientSecret": "...(omitted)...", "OIDCDiscoveryURL": "https://my-corp-app-name.auth0.com/" } } ``` ## JWT Verification JWT signatures will be verified against public keys from the issuer via OIDC discovery. Keys will be fetched from the OIDC Discovery URL during authentication and OIDC validation criteria (e.g. `iss`, `aud`, etc.) will be applied. ## OIDC Authentication Consul includes two built-in OIDC login flows: the Consul UI, and the CLI using [`consul login`](/commands/login). ### Redirect URIs An important part of OIDC auth method configuration is properly setting redirect URIs. This must be done both in Consul and with the OIDC provider, and these configurations must align. The redirect URIs are specified for an auth method with the [`AllowedRedirectURIs`](#allowedredirecturis) parameter. There are different redirect URIs to configure the Consul UI and CLI flows, so one or both will need to be set up depending on the installation. #### Consul UI Logging in via the Consul UI requires a redirect URI of the form: `http://localhost:8500/ui/oidc/callback` or `https://{host:port}/ui/oidc/callback` The "host:port" must be correct for the Consul agent serving the Consul UI. #### CLI If you plan to support authentication via `consul login -type=oidc -method=`, a localhost redirect URI must be set (usually this is `http://localhost:8550/oidc/callback`). Logins via the CLI may specify a different host and/or listening port if needed, and a URI with this host/port must match one of the configured redirected URIs. These same "localhost" URIs must be added to the provider as well. ### OIDC Login #### Consul UI 1. Click the "Log in" link at the top right of the menu bar. 2. Click one of the "Continue with..." buttons for your OIDC auth method of choice. 3. Complete the authentication with the configured provider. #### CLI ```shell-session $ consul login -method=oidc -type=oidc -token-sink-file=consul.token Complete the login via your OIDC provider. Launching browser to: https://myco.auth0.com/authorize?redirect_uri=http%3A%2F%2Flocalhost%3A8550%2Foidc%2Fcallback&client_id=r3qXc2bix9eF... ``` The browser will open to the generated URL to complete the provider's login. The URL may be entered manually if the browser cannot be automatically opened. The callback listener may be customized with the following optional parameters. These are typically not required to be set: The callback listener defaults to listen on `localhost:8550`. If you want to customize that use the optional flag [`-oidc-callback-listen-addr=`](/commands/login#oidc-callback-listen-addr). ## OIDC Configuration Troubleshooting The amount of configuration required for OIDC is relatively small, but it can be tricky to debug why things aren't working. Some tips for setting up OIDC: - Monitor the log output for the Consul servers. Important information about OIDC validation failures will be emitted. - Ensure Redirect URIs are correct in Consul and on the provider. They need to match exactly. Check: http/https, 127.0.0.1/localhost, port numbers, whether trailing slashes are present. - [`BoundAudiences`](#boundaudiences) is optional and typically not required. OIDC providers will use the `client_id` as the audience and OIDC validation expects this. - Check your provider for what scopes are required in order to receive all of the information you need. The scopes "profile" and "groups" often need to be requested, and can be added by setting `[OIDCScopes](#oidcscopes)="profile,groups"` on the auth method. - If you're seeing claim-related errors in logs, review the provider's docs very carefully to see how they're naming and structuring their claims. Depending on the provider, you may be able to construct a simple `curl` [implicit grant](https://developer.okta.com/blog/2018/05/24/what-is-the-oauth2-implicit-grant-type) request to obtain a JWT that you can inspect. An example of how to decode the JWT (in this case located in the `access_token` field of a JSON response): cat jwt.json | jq -r .access_token | cut -d. -f2 | base64 -D - The [`VerboseOIDCLogging`](#verboseoidclogging) option is available which will log the received OIDC token if debug level logging is enabled. This can be helpful when debugging provider setup and verifying that the received claims are what you expect. Since claims data is logged verbatim and may contain sensitive information, this option should not be used in production. @include 'jwt_claim_mapping_details.mdx'