Changeset

--- a/mod_http_oauth2/README.markdown	Thu Apr 06 16:10:27 2023 +0100
+++ b/mod_http_oauth2/README.markdown	Thu Apr 06 17:24:16 2023 +0100
@@ -8,15 +8,92 @@
     - html
 ...
 
-Introduction
-============
+## Introduction
+
+This module implements an OAuth2/OpenID Connect (OIDC) provider HTTP frontend
+on top of Prosody's usual internal authentication backend.
+
+OAuth and OIDC are web standards that allow you to provide clients and
+third-party applications limited access to your account, without sharing your
+password with them.
+
+With this module deployed, software that supports OAuth can obtain "access
+tokens" from Prosody which can then be used to connect to XMPP accounts using
+the 'OAUTHBEARER' SASL mechanism or via non-XMPP interfaces such as mod_rest.
+
+Although this module has been around for some time, it has recently been
+significantly extended and largely rewritten to support OAuth/OIDC more fully.
 
-This module is a work-in-progress intended for developers only!
+As of April 2023, it should be considered **alpha** stage. It works, we have
+tested it, but it has not yet seen wider review, testing and deployment. At
+this stage we recommend it for experimental and test deployments only. For
+specific information, see the [deployment notes section](#deployment-notes)
+below.
+
+Known client implementations:
+
+- *(we need you!)*
+
+Support for OAUTHBEARER has been added to the Lua XMPP library, [verse](https://code.matthewwild.co.uk/verse).
+If you know of additional implementations, or are motivated to work on one,
+please let us know! We'd be happy to help (e.g. by providing a test server).
+
+## Standards support
+
+Notable supported standards:
+
+- [RFC 6749: The OAuth 2.0 Authorization Framework](https://www.rfc-editor.org/rfc/rfc6749)
+- [RFC 7628: A Set of Simple Authentication and Security Layer (SASL) Mechanisms for OAuth](https://www.rfc-editor.org/rfc/rfc7628)
+- [OpenID Connect Core 1.0](https://openid.net/specs/openid-connect-core-1_0.html)
+- [OpenID Connect Dynamic Client Registration 1.0](https://openid.net/specs/openid-connect-registration-1_0.html) & [RFC 7591: OAuth 2.0 Dynamic Client Registration](https://www.rfc-editor.org/rfc/rfc7591.html)
+- [OpenID Connect Discovery 1.0](https://openid.net/specs/openid-connect-discovery-1_0.html)
+
+## Configuration
 
-Configuration
-=============
+### Interface
+
+The module presents a web page to users to allow them to authenticate when
+a client requests access. Built-in pages are provided, but you may also theme
+or entirely override them.
+
+This module honours the 'site_name' configuration option that is also used by
+a number of other modules:
+
+```lua
+site_name = "My XMPP Server"
+```
+
+To provide custom templates, specify the path to the template directory:
+
+```lua
+oauth2_template_path = "/etc/prosody/custom-oauth2-templates"
+```
+
+Some templates support additional variables, that can be provided by the
+'oauth2_template_style' option:
 
-Dynamic client registration enabled by configuring a JWT key. Algorithm
+```lua
+oauth2_template_style = {
+  background_colour = "#ffffff";
+}
+```
+
+### Token parameters
+
+The following options configure the lifetime of tokens issued by the module.
+The defaults are recommended.
+
+```lua
+oauth2_access_token_ttl = 86400 -- 24 hours
+oauth2_refresh_token_ttl = nil -- unlimited unless revoked by the user
+```
+
+### Dynamic client registration
+
+To allow users to connect any compatible software, you should enable dynamic
+client registration.
+
+Dynamic client registration can be enabled by configuring a JWT key. Algorithm
 defaults to *HS256*.
 
 ```lua
@@ -25,6 +102,8 @@
 oauth2_registration_options = { default_ttl = 60 * 60 * 24 * 90 }
 ```
 
+### Supported flows
+
 Various flows can be disabled and enabled with
 `allowed_oauth2_grant_types` and `allowed_oauth2_response_types`:
 
@@ -40,8 +119,29 @@
 }
 ```
 
+## Deployment notes
 
-Compatibility
-=============
+### Access management
+
+This module does not provide an interface for users to manage what they have
+granted access to their account! (e.g. to view and revoke clients they have
+previously authorized). It is recommended to join this module with
+mod_client_management to provide such access. However, at the time of writing,
+no XMPP clients currently support the protocol used by that module. We plan to
+work on additional interfaces in the future.
+
+### Scopes
 
-Requires Prosody 0.12+ or trunk.
+OAuth supports "scopes" as a way to grant clients limited access.
+
+There are currently no standard scopes defined for XMPP. This is something
+that we intend to change, e.g. by definitions provided in a future XEP. This
+means that clients you authorize currently have unrestricted access to your
+account (including the ability to change your password and lock you out!). So,
+for now, while using OAuth clients can prevent leaking your password to them,
+it is not currently suitable for connecting untrusted clients to your account.
+
+## Compatibility
+
+Requires Prosody trunk (April 2023), **not** compatible with Prosody 0.12 or
+earlier.