# DSL: AshAuthentication.Strategy.Oidc Strategy for authentication using an [OpenID Connect](https://openid.net/connect/) compatible server as the source of truth. This strategy builds on-top of `AshAuthentication.Strategy.OAuth2` and [`assent`](https://hex.pm/packages/assent). In order to use OIDC you need to provide the following minimum configuration: - `client_id` - The client id, required - `site` - The OIDC issuer, required - `openid_configuration_uri` - The URI for OpenID Provider, optional, defaults to `/.well-known/openid-configuration` - `client_authentication_method` - The Client Authentication method to use, optional, defaults to `client_secret_basic` - `client_secret` - The client secret, required if `:client_authentication_method` is `:client_secret_basic`, `:client_secret_post`, or `:client_secret_jwt` - `openid_configuration` - The OpenID configuration, optional, the configuration will be fetched from `:openid_configuration_uri` if this is not defined - `id_token_signed_response_alg` - The `id_token_signed_response_alg` parameter sent by the Client during Registration, defaults to `RS256` - `id_token_ttl_seconds` - The number of seconds from `iat` that an ID Token will be considered valid, optional, defaults to nil - `nonce` - The nonce to use for authorization request, optional, MUST be session based and unguessable. ## Nonce `nonce` can be set in the provider config. The `nonce` will be returned in the `session_params` along with `state`. You can use this to store the value in the current session e.g. a httpOnly session cookie. A random value generator can look like this: ```elixir 16 |> :crypto.strong_rand_bytes() |> Base.encode64(padding: false) ``` AshAuthentication will dynamically generate one for the session if `nonce` is set to `true`. ## DSL Documentation Provides an OpenID Connect authentication strategy. This strategy is built using the `:oauth2` strategy, and thus provides all the same configuration options should you need them. #### Schema: * `:name` (`t:atom/0`) - Required. Uniquely identifies the strategy. * `:client_id` - Required. The OAuth2 client ID. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir client_id fn _, resource -> :my_app |> Application.get_env(resource, []) |> Keyword.fetch(:oauth_client_id) end ``` * `:site` - Required. The base URL of the OAuth2 server - including the leading protocol (ie `https://`). Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir site fn _, resource -> :my_app |> Application.get_env(resource, []) |> Keyword.fetch(:oauth_site) end ``` * `:auth_method` - The authentication strategy used, optional. If not set, no authentication will be used during the access token request. The value may be one of the following: * `:client_secret_basic` * `:client_secret_post` * `:client_secret_jwt` * `:private_key_jwt` Valid values are nil, :client_secret_basic, :client_secret_post, :client_secret_jwt, :private_key_jwt The default value is `:client_secret_post`. * `:client_secret` - The OAuth2 client secret. Required if :auth_method is `:client_secret_basic`, `:client_secret_post` or `:client_secret_jwt`. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir site fn _, resource -> :my_app |> Application.get_env(resource, []) |> Keyword.fetch(:oauth_site) end ``` * `:authorize_url` - Required. The API url to the OAuth2 authorize endpoint. Relative to the value of `site`. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir authorize_url fn _, _ -> {:ok, "https://exampe.com/authorize"} end ``` * `:token_url` - Required. The API url to access the token endpoint. Relative to the value of `site`. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir token_url fn _, _ -> {:ok, "https://example.com/oauth_token"} end ``` * `:private_key` - The private key to use if `:auth_method` is `:private_key_jwt` Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. * `:redirect_uri` - Required. The callback URI base. Not the whole URI back to the callback endpoint, but the URI to your `AuthPlug`. We can generate the rest. Whilst not particularly secret, it seemed prudent to allow this to be configured dynamically so that you can use different URIs for different environments. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. * `:authorization_params` (`t:keyword/0`) - Any additional parameters to encode in the request phase. eg: `authorization_params scope: "openid profile email"` The default value is `[]`. * `:registration_enabled?` (`t:boolean/0`) - Is registration enabled for this provider? If this option is enabled, then new users will be able to register for your site when authenticating and not already present. If not, then only existing users will be able to authenticate. The default value is `true`. * `:register_action_name` (`t:atom/0`) - The name of the action to use to register a user. Only needed if `registration_enabled?` is `true`. Because we we don't know the response format of the server, you must implement your own registration action of the same name. See the "Registration and Sign-in" section of the module documentation for more information. The default is computed from the strategy name eg: `register_with_#{name}`. * `:sign_in_action_name` (`t:atom/0`) - The name of the action to use to sign in an existing user. Only needed if `registration_enabled?` is `false`. Because we don't know the response format of the server, you must implement your own sign-in action of the same name. See the "Registration and Sign-in" section of the module documentation for more information. The default is computed from the strategy name, eg: `sign_in_with_#{name}`. * `:identity_resource` - The resource used to store user identities. Given that a user can be signed into multiple different authentication providers at once we use the `AshAuthentication.UserIdentity` resource to build a mapping between users, providers and that provider's uid. See the Identities section of the module documentation for more information. Set to `false` to disable. The default value is `false`. * `:identity_relationship_name` (`t:atom/0`) - Name of the relationship to the provider identities resource The default value is `:identities`. * `:identity_relationship_user_id_attribute` (`t:atom/0`) - The name of the destination (user_id) attribute on your provider identity resource. The only reason to change this would be if you changed the `user_id_attribute_name` option of the provider identity. The default value is `:user_id`. * `:icon` (`t:atom/0`) - The name of an icon to use in any potential UI. This is a *hint* for UI generators to use, and not in any way canonical. The default value is `:oauth2`. * `:openid_configuration_uri` (`t:String.t/0`) - The URI for the OpenID provider The default value is `"/.well-known/openid-configuration"`. * `:client_authentication_method` - The client authentication method to use. Valid values are :client_secret_basic, :client_secret_post, :client_secret_jwt, :private_key_jwt The default value is `:client_secret_basic`. * `:openid_configuration` (`t:map/0`) - The OpenID configuration. If not set, the configuration will be retrieved from `openid_configuration_uri`. The default value is `%{}`. * `:id_token_signed_response_alg` - The `id_token_signed_response_alg` parameter sent by the Client during Registration. Valid values are "HS256", "HS384", "HS512", "RS256", "RS384", "RS512", "ES256", "ES384", "ES512", "PS256", "PS384", "PS512", "Ed25519", "Ed25519ph", "Ed448", "Ed448ph", "EdDSA" The default value is `"RS256"`. * `:id_token_ttl_seconds` - The number of seconds from `iat` that an ID Token will be considered valid. The default value is `nil`. * `:nonce` - A function for generating the session nonce. When set to `true` the nonce will be automatically generated using `AshAuthentication.Strategy.Oidc.NonceGenerator`. Set to `false` to explicitly disable. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir nonce fn _, _ -> 16 |> :crypto.strong_rand_bytes() |> Base.encode64(padding: false) end ``` The default value is `true`. * `:trusted_audiences` - A list of audiences which are trusted. The default value is `nil`. ## authentication.strategies.oidc ```elixir oidc name \ :oidc ``` Provides an OpenID Connect authentication strategy. This strategy is built using the `:oauth2` strategy, and thus provides all the same configuration options should you need them. ###### Schema: ### Options

Name	Type	Default	Docs
name *	atom		Uniquely identifies the strategy.
client_id *	(any, any -> any) | module | String.t		The OAuth2 client ID. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir client_id fn _, resource -> :my_app |> Application.get_env(resource, []) |> Keyword.fetch(:oauth_client_id) end ```
site *	(any, any -> any) | module | String.t		The base URL of the OAuth2 server - including the leading protocol (ie `https://`). Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir site fn _, resource -> :my_app |> Application.get_env(resource, []) |> Keyword.fetch(:oauth_site) end ```
authorize_url *	(any, any -> any) | module | String.t		The API url to the OAuth2 authorize endpoint. Relative to the value of `site`. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir authorize_url fn _, _ -> {:ok, "https://exampe.com/authorize"} end ```
token_url *	(any, any -> any) | module | String.t		The API url to access the token endpoint. Relative to the value of `site`. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir token_url fn _, _ -> {:ok, "https://example.com/oauth_token"} end ```
redirect_uri *	(any, any -> any) | module | String.t		The callback URI base. Not the whole URI back to the callback endpoint, but the URI to your `AuthPlug`. We can generate the rest. Whilst not particularly secret, it seemed prudent to allow this to be configured dynamically so that you can use different URIs for different environments. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information.
auth_method	nil | :client_secret_basic | :client_secret_post | :client_secret_jwt | :private_key_jwt	:client_secret_post	The authentication strategy used, optional. If not set, no authentication will be used during the access token request. The value may be one of the following: * `:client_secret_basic` * `:client_secret_post` * `:client_secret_jwt` * `:private_key_jwt`
client_secret	(any, any -> any) | module | String.t		The OAuth2 client secret. Required if :auth_method is `:client_secret_basic`, `:client_secret_post` or `:client_secret_jwt`. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir site fn _, resource -> :my_app |> Application.get_env(resource, []) |> Keyword.fetch(:oauth_site) end ```
private_key	(any, any -> any) | module | String.t		The private key to use if `:auth_method` is `:private_key_jwt` Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information.
authorization_params	Keyword.t	[]	Any additional parameters to encode in the request phase. eg: `authorization_params scope: "openid profile email"`
registration_enabled?	boolean	true	Is registration enabled for this provider? If this option is enabled, then new users will be able to register for your site when authenticating and not already present. If not, then only existing users will be able to authenticate.
register_action_name	atom		The name of the action to use to register a user. Only needed if `registration_enabled?` is `true`. Because we we don't know the response format of the server, you must implement your own registration action of the same name. See the "Registration and Sign-in" section of the module documentation for more information. The default is computed from the strategy name eg: `register_with_#{name}`.
sign_in_action_name	atom		The name of the action to use to sign in an existing user. Only needed if `registration_enabled?` is `false`. Because we don't know the response format of the server, you must implement your own sign-in action of the same name. See the "Registration and Sign-in" section of the module documentation for more information. The default is computed from the strategy name, eg: `sign_in_with_#{name}`.
identity_resource	module | false	false	The resource used to store user identities. Given that a user can be signed into multiple different authentication providers at once we use the `AshAuthentication.UserIdentity` resource to build a mapping between users, providers and that provider's uid. See the Identities section of the module documentation for more information. Set to `false` to disable.
identity_relationship_name	atom	:identities	Name of the relationship to the provider identities resource
identity_relationship_user_id_attribute	atom	:user_id	The name of the destination (user_id) attribute on your provider identity resource. The only reason to change this would be if you changed the `user_id_attribute_name` option of the provider identity.
icon	atom	:oauth2	The name of an icon to use in any potential UI. This is a *hint* for UI generators to use, and not in any way canonical.
openid_configuration_uri	String.t	"/.well-known/openid-configuration"	The URI for the OpenID provider
client_authentication_method	:client_secret_basic | :client_secret_post | :client_secret_jwt | :private_key_jwt	:client_secret_basic	The client authentication method to use.
openid_configuration	map	%{}	The OpenID configuration. If not set, the configuration will be retrieved from `openid_configuration_uri`.
id_token_signed_response_alg	"HS256" | "HS384" | "HS512" | "RS256" | "RS384" | "RS512" | "ES256" | "ES384" | "ES512" | "PS256" | "PS384" | "PS512" | "Ed25519" | "Ed25519ph" | "Ed448" | "Ed448ph" | "EdDSA"	"RS256"	The `id_token_signed_response_alg` parameter sent by the Client during Registration.
id_token_ttl_seconds	nil | pos_integer		The number of seconds from `iat` that an ID Token will be considered valid.
nonce	boolean | (any, any -> any) | module | String.t	true	A function for generating the session nonce. When set to `true` the nonce will be automatically generated using `AshAuthentication.Strategy.Oidc.NonceGenerator`. Set to `false` to explicitly disable. Takes either a module which implements the `AshAuthentication.Secret` behaviour, a 2 arity anonymous function or a string. See the module documentation for `AshAuthentication.Secret` for more information. Example: ```elixir nonce fn _, _ -> 16 |> :crypto.strong_rand_bytes() |> Base.encode64(padding: false) end ```
trusted_audiences	nil | list(String.t)		A list of audiences which are trusted.

### Introspection Target: `AshAuthentication.Strategy.OAuth2`