--- title: "Proxy Authorization" description: "A reference guide on Proxy Authorization implementations" lead: "This section contains reference guide on Proxy Authorization implementations Authelia supports." date: 2023-01-25T20:36:40+11:00 draft: false images: [] menu: reference: parent: "guides" weight: 220 toc: true aliases: - /r/proxy-authz --- Proxies can integrate with Authelia via several authorization endpoints. These endpoints are by default configured appropriately for most use cases; however they can be individually configured, removed, added, etc. They are currently divided into two sections: - [Implementations](#implementations) - [Authn Strategies](#authn-strategies) These endpoints are meant to collect important information from these requests via headers to determine both metadata about the request (such as the resource and IP address of the user) which is determined via the [Implementations](#implementations), and the identity of the user which is determined via the [Authn Strategies](#authn-strategies). ## Default Endpoints | Name | Path | [Implementation] | [Authn Strategies] | |:------------:|:-----------------------:|:----------------:|:------------------------------------------------------:| | forward-auth | /api/authz/forward-auth | [ForwardAuth] | [HeaderProxyAuthorization], [CookieSession] | | ext-authz | /api/authz/ext-authz | [ExtAuthz] | [HeaderProxyAuthorization], [CookieSession] | | auth-request | /api/authz/auth-request | [AuthRequest] | [HeaderAuthRequestProxyAuthorization], [CookieSession] | | legacy | /api/verify | [Legacy] | [HeaderLegacy], [CookieSession] | ## Metadata Various metadata is collected from the request made to the Authelia authorization server. This table describes the metadata collected. All of this metadata is utilized for the purpose of determining if the user is authorized to a particular resource. | Name | Description | |:------------:|:-----------------------------------------------:| | Method | The Method Verb of the Request | | Scheme | The URI Scheme of the Request | | Hostname | The URI Hostname of the Request | | Path | The URI Path of the Request | | IP | The IP address of the client making the Request | | Authelia URL | The URL of the Authelia Portal | Some values may have either fallbacks or override values. If they exist they will be in the alternatives table which will be below the main metadata table. The metadata table contains the recommended source of this information and this source is often times automatic depending on the proxy implementation. The difference between an override and a fallback is an override values will take precedence over the metadata values, and fallbacks only take effect if the override values or metadata values are completely unset. ## Implementations ### ForwardAuth This is the implementation which supports [Traefik] via the [ForwardAuth Middleware], [Caddy] via the [forward_auth directive], and [Skipper] via the [webhook auth filter]. #### ForwardAuth Metadata | Metadata | Source | Key | |:------------:|:----------------------------:|:--------------------:| | Method | [Header] | `X-Forwarded-Method` | | Scheme | [Header] | [X-Forwarded-Proto] | | Hostname | [Header] | [X-Forwarded-Host] | | Path | [Header] | `X-Forwarded-URI` | | IP | [Header] | [X-Forwarded-For] | | Authelia URL | Session Cookie Configuration | `authelia_url` | #### ForwardAuth Metadata Alternatives | Metadata | Alternative Type | Source | Key | |:------------:|:----------------:|:--------------:|:--------------:| | Scheme | Fallback | [Header] | Server Scheme | | IP | Fallback | TCP Packet | Source IP | | Authelia URL | Override | Query Argument | `authelia_url` | ### ExtAuthz This is the implementation which supports [Envoy] via the [ExtAuthz Extension Filter]. #### ExtAuthz Metadata | Metadata | Source | Key | |:------------:|:----------------------------:|:-------------------:| | Method | _[Start Line]_ | [HTTP Method] | | Scheme | [Header] | [X-Forwarded-Proto] | | Hostname | [Header] | [Host] | | Path | [Header] | Endpoint Sub-Path | | IP | [Header] | [X-Forwarded-For] | | Authelia URL | Session Cookie Configuration | `authelia_url` | #### ExtAuthz Metadata Alternatives | Metadata | Alternative Type | Source | Key | |:------------:|:----------------:|:----------:|:------------------:| | Scheme | Fallback | [Header] | Server Scheme | | IP | Fallback | TCP Packet | Source IP | | Authelia URL | Override | [Header] | `X-Authelia-URL` | ### AuthRequest This is the implementation which supports [NGINX] via the [auth_request HTTP module] and [HAProxy] via the [auth-request lua plugin]. | Metadata | Source | Key | |:------------:|:--------:|:-------------------:| | Method | [Header] | `X-Original-Method` | | Scheme | [Header] | `X-Original-URL` | | Hostname | [Header] | `X-Original-URL` | | Path | [Header] | `X-Original-URL` | | IP | [Header] | [X-Forwarded-For] | | Authelia URL | _N/A_ | _N/A_ | _**Note:** This endpoint does not support automatic redirection. This is because there is no support on NGINX's side to achieve this with `ngx_http_auth_request_module` and the redirection must be performed within the NGINX configuration._ #### AuthRequest Metadata Alternatives | Metadata | Alternative Type | Source | Key | |:--------:|:----------------:|:----------:|:---------:| | IP | Fallback | TCP Packet | Source IP | ### Legacy This is the legacy implementation which used to operate similar to both the [ForwardAuth](#forwardauth) and [AuthRequest](#authrequest) implementations. *__Note:__ This implementation has duplicate entries for metadata. This is due to the fact this implementation used to cater for the AuthRequest and ForwardAuth implementations. The table is in order of precedence where if a header higher in the list exists it is used over those lower in the list.* | Metadata | Source | Key | |:------------:|:--------------:|:--------------------:| | Method | [Header] | `X-Original-Method` | | Scheme | [Header] | `X-Original-URL` | | Hostname | [Header] | `X-Original-URL` | | Path | [Header] | `X-Original-URL` | | Method | [Header] | `X-Forwarded-Method` | | Scheme | [Header] | [X-Forwarded-Proto] | | Hostname | [Header] | [X-Forwarded-Host] | | Path | [Header] | `X-Forwarded-URI` | | IP | [Header] | [X-Forwarded-For] | | Authelia URL | Query Argument | `rd` | | Authelia URL | [Header] | `X-Authelia-URL` | ## Authn Strategies Authentication strategies are used to determine the users identity which is essential to determining if they are authorized to visit a particular resource. Authentication strategies are executed in order, and have three potential results. 1. Successful Authentication 2. No Authentication 3. Unsuccessful Authentication Result 2 is the only result in which the next strategy is attempted, this occurs when there is not enough information in the request to perform authentication. Both result 1 and 2 result in a short-circuit, i.e. no other strategy will be attempted. Result 1 occurs when the strategy requirements (i.e. a particular header) are present and the details are sufficient to authenticate them and the details are correct. Result 2 occurs when the strategy requirements are present and either the details are incomplete (i.e. malformed header) or the details are incorrect (i.e. bad password). ### CookieSession This strategy uses a cookie which links the user to a session to determine the users identity. This is the default strategy for end-users. If this strategy if included in an endpoint will redirect the user the Authelia Authorization Portal on supported proxies when they are not authorized and can potentially be authorized provided no other strategies have critical errors. ### HeaderAuthorization This strategy uses the [Authorization] header to determine the users' identity. If the user credentials are wrong, or the header is malformed it will respond with the [WWW-Authenticate] header and a [401 Unauthorized] status code. ### HeaderProxyAuthorization This strategy uses the [Proxy-Authorization] header to determine the users' identity. If the user credentials are wrong, or the header is malformed it will respond with the [Proxy-Authenticate] header and a [407 Proxy Authentication Required] status code. ### HeaderAuthRequestProxyAuthorization This strategy uses the [Proxy-Authorization] header to determine the users' identity. If the user credentials are wrong, or the header is malformed it will respond with the [WWW-Authenticate] header and a [401 Unauthorized] status code. It is specifically intended for use with the [AuthRequest] implementation. ### HeaderLegacy This strategy uses the [Proxy-Authorization] header to determine the users' identity. If the user credentials are wrong, or the header is malformed it will respond with the [WWW-Authenticate] header. [401 Unauthorized]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/401 [407 Proxy Authentication Required]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/407 [NGINX]: https://www.nginx.com/ [Traefik]: https://traefik.io/traefik/ [Envoy]: https://www.envoyproxy.io/ [Caddy]: https://caddyserver.com/ [Skipper]: https://opensource.zalando.com/skipper/ [HAProxy]: http://www.haproxy.org/ [ExtAuthz Extension Filter]: https://www.envoyproxy.io/docs/envoy/latest/api-v3/extensions/filters/http/ext_authz/v3/ext_authz.proto#envoy-v3-api-msg-extensions-filters-http-ext-authz-v3-extauthz [auth_request HTTP module]: https://nginx.org/en/docs/http/ngx_http_auth_request_module.html [auth-request lua plugin]: https://github.com/TimWolla/haproxy-auth-request [ForwardAuth Middleware]: https://doc.traefik.io/traefik/middlewares/http/forwardauth/ [forward_auth directive]: https://caddyserver.com/docs/caddyfile/directives/forward_auth [webhook auth filter]: https://opensource.zalando.com/skipper/reference/filters/#webhook [Implementation]: #implementations [Authn Strategies]: #authn-strategies [ForwardAuth]: #forwardauth [ExtAuthz]: #extauthz [AuthRequest]: #authrequest [Legacy]: #legacy [HeaderProxyAuthorization]: #headerproxyauthorization [HeaderAuthRequestProxyAuthorization]: #headerauthrequestproxyauthorization [HeaderLegacy]: #headerlegacy [CookieSession]: #cookiesession [Authorization]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Authorization [WWW-Authenticate]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/WWW-Authenticate [Proxy-Authorization]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Proxy-Authorization [Proxy-Authenticate]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Proxy-Authenticate [X-Forwarded-Proto]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-Proto [X-Forwarded-Host]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-Host [X-Forwarded-For]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-For [Host]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Host [HTTP Method]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods [HTTP Method]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods [Start Line]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Messages#start_line [Header]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers