MSC3824: OIDC aware clients

[hughns]

Rendered

• [x] Spec is feature complete
• [x] Reviewed for consistency with MSC3861
• [x] Implementations believed to be complete enough

Dependencies:

• https://github.com/matrix-org/matrix-spec-proposals/pull/3861

Servers

• [x] Synapse implementation: https://github.com/sandhose/synapse/tree/quenting/oauth-delegation
• [x] Matrix Authentication Service support within it's compatibility layer: https://github.com/matrix-org/matrix-authentication-service/pull/221

Clients

• [x] Support in matrix-js-sdk: https://github.com/matrix-org/matrix-js-sdk/pull/2398
• [x] Element Web implementation via matrix-react-sdk: https://github.com/matrix-org/matrix-react-sdk/pull/8681
• [x] Element Android implementation: https://github.com/vector-im/element-android/pull/7920
• [ ] Element iOS implementation

[hughns]

Draft implementation in matrix-js-sdk: https://github.com/matrix-org/matrix-js-sdk/pull/2398 Draft implementation in matrix-react-sdk: https://github.com/matrix-org/matrix-react-sdk/pull/8681

[turt2live]

(implementation nor the MSC have been sufficiently reviewed to remove the label - when someone on the SCT is comfortable with where things are at, they'll remove the label. Personally, I haven't gotten as far as deciding if I'm comfortable with it 😅)

[sandhose]

I think an important part of this would also be to be able to advertise what actions are available with each login method, e.g.

{
  "flows": [{
    "type": "m.login.password",
    "actions": ["login"],
  }, {
    "type": "m.login.sso",
    "actions": ["login", "register"]
  }]
}

This would allow clients to properly display what's really available for each login method

[hughns]

~~I've had an initial go at Synapse support in https://github.com/matrix-org/synapse/pull/12924~~.

Matrix Authentication Service support within it's compatibility layer is in https://github.com/matrix-org/matrix-authentication-service/pull/221

[hughns]

The Web support has been merged so I think that this is ready for review. Android implementation is done too but not yet merged.