From c695328d99dd75191f2412358ca3ba6361bce20e Mon Sep 17 00:00:00 2001 From: Travis Ralston Date: Thu, 18 May 2023 22:06:52 -0600 Subject: [PATCH] Specify MSC3882: Using an existing session to log in another MSC: https://github.com/matrix-org/matrix-spec-proposals/pull/3882 --- content/client-server-api/_index.md | 3 + data/api/client-server/login.yaml | 97 ++++++++++++++++++++++++++++- 2 files changed, 99 insertions(+), 1 deletion(-) diff --git a/content/client-server-api/_index.md b/content/client-server-api/_index.md index 798835a0..6c6b874e 100644 --- a/content/client-server-api/_index.md +++ b/content/client-server-api/_index.md @@ -1176,6 +1176,9 @@ client supports it, the client should redirect the user to the is complete, the client will need to submit a `/login` request matching `m.login.token`. +{{< added-in v="1.7" >}} Already-authenticated clients can additionally generate +a token for their user ID if supported by the homeserver using `POST /login/get_token`. + {{% http-api spec="client-server" api="login" %}} {{% http-api spec="client-server" api="refresh" %}} diff --git a/data/api/client-server/login.yaml b/data/api/client-server/login.yaml index 7c33d1a4..36b44153 100644 --- a/data/api/client-server/login.yaml +++ b/data/api/client-server/login.yaml @@ -42,7 +42,8 @@ paths: examples: application/json: { "flows": [ - {"type": "m.login.password"} + {"type": "m.login.password"}, + {"type": "m.login.token", "get_login_token": true} ] } schema: @@ -54,12 +55,22 @@ paths: items: type: object title: LoginFlow + required: ['type'] properties: type: description: |- The login type. This is supplied as the `type` when logging in. type: string + get_login_token: + type: boolean + x-addedInMatrixVersion: "1.7" + description: |- + If `type` is `m.login.token`, an optional field to indicate + to the unauthenticated client that the homeserver supports + the `POST /login/get_token` endpoint. Note that supporting + the endpoint does not necessarily indicate that the user + attempting to log in will be able to generate such a token. 429: description: This request was rate-limited. schema: @@ -240,3 +251,87 @@ paths: "$ref": "definitions/errors/rate_limited.yaml" tags: - Session management + "/login/get_token": + post: + summary: Optional endpoint to generate a single-use, time-limited, `m.login.token` token. + description: |- + Optional endpoint - the server is not required to implement this endpoint if it does not + intend to use or support this functionality. + + This API endpoint uses the [User-Interactive Authentication API](/client-server-api/#user-interactive-authentication-api). + + An already-authenticated client would call this endpoint to generate a single-use, time-limited, + token for an unauthenticated client to log in with, becoming logged in as the same user which + called this endpoint. The unauthenticated client uses the generated token in a `m.login.token` + login flow with the homeserver. + + Clients, both authenticated and unauthenticated, might wish to hide user interface which exposes + this feature if the server is not offering it. Authenticated clients can check for support on + a per-user basis with the `m.get_login_token` [capability](/client-server-api/#capabilities-negotiation), + while unauthenticated clients can detect server support by looking for an `m.login.token` login + flow with `get_login_token: true` on [`GET /login`](/client-server-api/#post_matrixclientv3login). + + In v1.7 of the specification, transmission of the generated token to an unauthenticated client is + left as an implementation detail. Future MSCs such as [MSC3906](https://github.com/matrix-org/matrix-spec-proposals/pull/3906) + might standarise a way to transmit the token between clients. + + The generated token MUST only be valid for a single login, enforced by the server. Clients which + intend to log in multiple devices must generate a token for each. + + With other User-Interactive Authentication (UIA)-supporting endpoints, servers sometimes do not re-prompt + for verification if the session recently passed UIA. For this endpoint, servers should always re-prompt + the user for verification to ensure explicit consent is gained for each additional client. + + Servers are encouraged to apply stricter than normal rate limiting to this endpoint, such as maximum + of 1 request per minute. + operationId: generateLoginToken + x-addedInMatrixVersion: "1.7" + security: + - accessToken: [] + parameters: + - in: body + name: body + required: true + schema: + type: object + description: An empty JSON object. + responses: + 200: + description: The login token an unauthenticated client can use to log in as the requesting user. + examples: + application/json: { + "login_token": "", + "expires_in_ms": 120000 + } + schema: + type: object + required: ["login_token", "expires_in_ms"] + properties: + login_token: + type: string + description: The login token for the `m.login.token` login flow. + expires_in_ms: + type: integer + description: |- + The time remaining in milliseconds until the homeserver will no longer accept the token. `120000` + (2 minutes) is recommended as a default. + 400: + description: |- + The request was malformed, or the user does not have an ability to generate tokens for their devices, + as implied by the [User-Interactive Authentication API](/client-server-api/#user-interactive-authentication-api). + + Clients should verify whether the user has an ability to call this endpoint with the `m.get_login_token` + [capability](/client-server-api/#capabilities-negotiation). + schema: + "$ref": "definitions/errors/error.yaml" + 401: + description: |- + The homeserver requires additional authentication information. + schema: + "$ref": "definitions/auth_response.yaml" + 429: + description: This request was rate-limited. + schema: + "$ref": "definitions/errors/rate_limited.yaml" + tags: + - Session management \ No newline at end of file