forgejo/docs/content/development/oauth2-provider.en-us.md

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---
date: "2023-06-01T08:40:00+08:00"
title: "OAuth2 provider"
slug: "oauth2-provider"
sidebar_position: 41
toc: false
draft: false
aliases:
- /en-us/oauth2-provider
menu:
sidebar:
parent: "development"
name: "OAuth2 Provider"
sidebar_position: 41
identifier: "oauth2-provider"
---
# OAuth2 provider
Gitea supports acting as an OAuth2 provider to allow third party applications to access its resources with the user's consent. This feature is available since release 1.8.0.
## Endpoints
| Endpoint | URL |
| ------------------------ | ----------------------------------- |
| OpenID Connect Discovery | `/.well-known/openid-configuration` |
| Authorization Endpoint | `/login/oauth/authorize` |
| Access Token Endpoint | `/login/oauth/access_token` |
| OpenID Connect UserInfo | `/login/oauth/userinfo` |
| JSON Web Key Set | `/login/oauth/keys` |
## Supported OAuth2 Grants
At the moment Gitea only supports the [**Authorization Code Grant**](https://tools.ietf.org/html/rfc6749#section-1.3.1) standard with additional support of the following extensions:
- [Proof Key for Code Exchange (PKCE)](https://tools.ietf.org/html/rfc7636)
- [OpenID Connect (OIDC)](https://openid.net/specs/openid-connect-core-1_0.html#CodeFlowAuth)
To use the Authorization Code Grant as a third party application it is required to register a new application via the "Settings" (`/user/settings/applications`) section of the settings. To test or debug you can use the web-tool https://oauthdebugger.com/.
## Scopes
Redesign Scoped Access Tokens (#24767) ## Changes - Adds the following high level access scopes, each with `read` and `write` levels: - `activitypub` - `admin` (hidden if user is not a site admin) - `misc` - `notification` - `organization` - `package` - `issue` - `repository` - `user` - Adds new middleware function `tokenRequiresScopes()` in addition to `reqToken()` - `tokenRequiresScopes()` is used for each high-level api section - _if_ a scoped token is present, checks that the required scope is included based on the section and HTTP method - `reqToken()` is used for individual routes - checks that required authentication is present (but does not check scope levels as this will already have been handled by `tokenRequiresScopes()` - Adds migration to convert old scoped access tokens to the new set of scopes - Updates the user interface for scope selection ### User interface example <img width="903" alt="Screen Shot 2023-05-31 at 1 56 55 PM" src="https://github.com/go-gitea/gitea/assets/23248839/654766ec-2143-4f59-9037-3b51600e32f3"> <img width="917" alt="Screen Shot 2023-05-31 at 1 56 43 PM" src="https://github.com/go-gitea/gitea/assets/23248839/1ad64081-012c-4a73-b393-66b30352654c"> ## tokenRequiresScopes Design Decision - `tokenRequiresScopes()` was added to more reliably cover api routes. For an incoming request, this function uses the given scope category (say `AccessTokenScopeCategoryOrganization`) and the HTTP method (say `DELETE`) and verifies that any scoped tokens in use include `delete:organization`. - `reqToken()` is used to enforce auth for individual routes that require it. If a scoped token is not present for a request, `tokenRequiresScopes()` will not return an error ## TODO - [x] Alphabetize scope categories - [x] Change 'public repos only' to a radio button (private vs public). Also expand this to organizations - [X] Disable token creation if no scopes selected. Alternatively, show warning - [x] `reqToken()` is missing from many `POST/DELETE` routes in the api. `tokenRequiresScopes()` only checks that a given token has the correct scope, `reqToken()` must be used to check that a token (or some other auth) is present. - _This should be addressed in this PR_ - [x] The migration should be reviewed very carefully in order to minimize access changes to existing user tokens. - _This should be addressed in this PR_ - [x] Link to api to swagger documentation, clarify what read/write/delete levels correspond to - [x] Review cases where more than one scope is needed as this directly deviates from the api definition. - _This should be addressed in this PR_ - For example: ```go m.Group("/users/{username}/orgs", func() { m.Get("", reqToken(), org.ListUserOrgs) m.Get("/{org}/permissions", reqToken(), org.GetUserOrgsPermissions) }, tokenRequiresScopes(auth_model.AccessTokenScopeCategoryUser, auth_model.AccessTokenScopeCategoryOrganization), context_service.UserAssignmentAPI()) ``` ## Future improvements - [ ] Add required scopes to swagger documentation - [ ] Redesign `reqToken()` to be opt-out rather than opt-in - [ ] Subdivide scopes like `repository` - [ ] Once a token is created, if it has no scopes, we should display text instead of an empty bullet point - [ ] If the 'public repos only' option is selected, should read categories be selected by default Closes #24501 Closes #24799 Co-authored-by: Jonathan Tran <jon@allspice.io> Co-authored-by: Kyle D <kdumontnu@gmail.com> Co-authored-by: silverwind <me@silverwind.io>
2023-06-04 18:57:16 +00:00
Gitea supports scoped access tokens, which allow users the ability to restrict tokens to operate only on selected url routes. Scopes are grouped by high-level API routes, and further refined to the following:
- `read`: `GET` routes
- `write`: `POST`, `PUT`, `PATCH`, and `DELETE` routes (in addition to `GET`)
Gitea token scopes are as follows:
| Name | Description |
| ---- |------------------------------------------------------------------------------------------------------------------------------------------------------|
| **(no scope)** | Not supported. A scope is required even for public repositories. |
| **activitypub** | `activitypub` API routes: ActivityPub related operations. |
| &nbsp;&nbsp;&nbsp; **read:activitypub** | Grants read access for ActivityPub operations. |
| &nbsp;&nbsp;&nbsp; **write:activitypub** | Grants read/write/delete access for ActivityPub operations. |
| **admin** | `/admin/*` API routes: Site-wide administrative operations (hidden for non-admin accounts). |
| &nbsp;&nbsp;&nbsp; **read:admin** | Grants read access for admin operations, such as getting cron jobs or registered user emails. |
| &nbsp;&nbsp;&nbsp; **write:admin** | Grants read/write/delete access for admin operations, such as running cron jobs or updating user accounts. |
| **issue** | `issues/*`, `labels/*`, `milestones/*` API routes: Issue-related operations. |
| &nbsp;&nbsp;&nbsp; **read:issue** | Grants read access for issues operations, such as getting issue comments, issue attachments, and milestones. |
| &nbsp;&nbsp;&nbsp; **write:issue** | Grants read/write/delete access for issues operations, such as posting or editing an issue comment or attachment, and updating milestones. |
| **misc** | Reserved for future usage. |
| &nbsp;&nbsp;&nbsp; **read:misc** | Reserved for future usage. |
| &nbsp;&nbsp;&nbsp; **write:misc** | Reserved for future usage. |
| **notification** | `notification/*` API routes: user notification operations. |
| &nbsp;&nbsp;&nbsp; **read:notification** | Grants read access to user notifications, such as which notifications users are subscribed to and read new notifications. |
| &nbsp;&nbsp;&nbsp; **write:notification** | Grants read/write/delete access to user notifications, such as marking notifications as read. |
| **organization** | `orgs/*` and `teams/*` API routes: Organization and team management operations. |
| &nbsp;&nbsp;&nbsp; **read:organization** | Grants read access to org and team status, such as listing all orgs a user has visibility to, teams, and team members. |
| &nbsp;&nbsp;&nbsp; **write:organization** | Grants read/write/delete access to org and team status, such as creating and updating teams and updating org settings. |
| **package** | `/packages/*` API routes: Packages operations |
| &nbsp;&nbsp;&nbsp; **read:package** | Grants read access to package operations, such as reading and downloading available packages. |
| &nbsp;&nbsp;&nbsp; **write:package** | Grants read/write/delete access to package operations. Currently the same as `read:package`. |
| **repository** | `/repos/*` API routes except `/repos/issues/*`: Repository file, pull-request, and release operations. |
| &nbsp;&nbsp;&nbsp; **read:repository** | Grants read access to repository operations, such as getting repository files, releases, collaborators. |
| &nbsp;&nbsp;&nbsp; **write:repository** | Grants read/write/delete access to repository operations, such as getting updating repository files, creating pull requests, updating collaborators. |
| **user** | `/user/*` and `/users/*` API routes: User-related operations. |
| &nbsp;&nbsp;&nbsp; **read:user** | Grants read access to user operations, such as getting user repo subscriptions and user settings. |
| &nbsp;&nbsp;&nbsp; **write:user** | Grants read/write/delete access to user operations, such as updating user repo subscriptions, followed users, and user settings. |
Record OAuth client type at registration (#21316) The OAuth spec [defines two types of client](https://datatracker.ietf.org/doc/html/rfc6749#section-2.1), confidential and public. Previously Gitea assumed all clients to be confidential. > OAuth defines two client types, based on their ability to authenticate securely with the authorization server (i.e., ability to > maintain the confidentiality of their client credentials): > > confidential > Clients capable of maintaining the confidentiality of their credentials (e.g., client implemented on a secure server with > restricted access to the client credentials), or capable of secure client authentication using other means. > > **public > Clients incapable of maintaining the confidentiality of their credentials (e.g., clients executing on the device used by the resource owner, such as an installed native application or a web browser-based application), and incapable of secure client authentication via any other means.** > > The client type designation is based on the authorization server's definition of secure authentication and its acceptable exposure levels of client credentials. The authorization server SHOULD NOT make assumptions about the client type. https://datatracker.ietf.org/doc/html/rfc8252#section-8.4 > Authorization servers MUST record the client type in the client registration details in order to identify and process requests accordingly. Require PKCE for public clients: https://datatracker.ietf.org/doc/html/rfc8252#section-8.1 > Authorization servers SHOULD reject authorization requests from native apps that don't use PKCE by returning an error message Fixes #21299 Co-authored-by: wxiaoguang <wxiaoguang@gmail.com> Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
2022-10-24 07:59:24 +00:00
## Client types
Gitea supports both confidential and public client types, [as defined by RFC 6749](https://datatracker.ietf.org/doc/html/rfc6749#section-2.1).
For public clients, a redirect URI of a loopback IP address such as `http://127.0.0.1/` allows any port. Avoid using `localhost`, [as recommended by RFC 8252](https://datatracker.ietf.org/doc/html/rfc8252#section-8.3).
## Examples
### Confidential client
**Note:** This example does not use PKCE.
1. Redirect the user to the authorization endpoint in order to get their consent for accessing the resources:
```curl
https://[YOUR-GITEA-URL]/login/oauth/authorize?client_id=CLIENT_ID&redirect_uri=REDIRECT_URI&response_type=code&state=STATE
```
The `CLIENT_ID` can be obtained by registering an application in the settings. The `STATE` is a random string that will be sent back to your application after the user authorizes. The `state` parameter is optional, but should be used to prevent CSRF attacks.
![Authorization Page](/authorize.png)
The user will now be asked to authorize your application. If they authorize it, the user will be redirected to the `REDIRECT_URL`, for example:
```curl
https://[REDIRECT_URI]?code=RETURNED_CODE&state=STATE
```
2. Using the provided `code` from the redirect, you can request a new application and refresh token. The access token endpoint accepts POST requests with `application/json` and `application/x-www-form-urlencoded` body, for example:
```curl
POST https://[YOUR-GITEA-URL]/login/oauth/access_token
```
```json
{
"client_id": "YOUR_CLIENT_ID",
"client_secret": "YOUR_CLIENT_SECRET",
"code": "RETURNED_CODE",
"grant_type": "authorization_code",
"redirect_uri": "REDIRECT_URI"
}
```
Response:
```json
{
"access_token": "eyJhbGciOiJIUzUxMiIsInR5cCI6IkpXVCJ9.eyJnbnQiOjIsInR0IjowLCJleHAiOjE1NTUxNzk5MTIsImlhdCI6MTU1NTE3NjMxMn0.0-iFsAwBtxuckA0sNZ6QpBQmywVPz129u75vOM7wPJecw5wqGyBkmstfJHAjEOqrAf_V5Z-1QYeCh_Cz4RiKug",
"token_type": "bearer",
"expires_in": 3600,
"refresh_token": "eyJhbGciOiJIUzUxMiIsInR5cCI6IkpXVCJ9.eyJnbnQiOjIsInR0IjoxLCJjbnQiOjEsImV4cCI6MTU1NzgwNDMxMiwiaWF0IjoxNTU1MTc2MzEyfQ.S_HZQBy4q9r5SEzNGNIoFClT43HPNDbUdHH-GYNYYdkRfft6XptJBkUQscZsGxOW975Yk6RbgtGvq1nkEcklOw"
}
```
The `CLIENT_SECRET` is the unique secret code generated for this application. Please note that the secret will only be visible after you created/registered the application with Gitea and cannot be recovered. If you lose the secret, you must regenerate the secret via the application's settings.
The `REDIRECT_URI` in the `access_token` request must match the `REDIRECT_URI` in the `authorize` request.
3. Use the `access_token` to make [API requests](https://docs.gitea.io/en-us/api-usage#oauth2) to access the user's resources.
### Public client (PKCE)
PKCE (Proof Key for Code Exchange) is an extension to the OAuth flow which allows for a secure credential exchange without the requirement to provide a client secret.
**Note**: Please ensure you have registered your OAuth application as a public client.
To achieve this, you have to provide a `code_verifier` for every authorization request. A `code_verifier` has to be a random string with a minimum length of 43 characters and a maximum length of 128 characters. It can contain alphanumeric characters as well as the characters `-`, `.`, `_` and `~`.
Using this `code_verifier` string, a new one called `code_challenge` is created by using one of two methods:
- If you have the required functionality on your client, set `code_challenge` to be a URL-safe base64-encoded string of the SHA256 hash of `code_verifier`. In that case, your `code_challenge_method` becomes `S256`.
- If you are unable to do so, you can provide your `code_verifier` as a plain string to `code_challenge`. Then you have to set your `code_challenge_method` as `plain`.
After you have generated this values, you can continue with your request.
1. Redirect the user to the authorization endpoint in order to get their consent for accessing the resources:
```curl
https://[YOUR-GITEA-URL]/login/oauth/authorize?client_id=CLIENT_ID&redirect_uri=REDIRECT_URI&response_type=code&code_challenge_method=CODE_CHALLENGE_METHOD&code_challenge=CODE_CHALLENGE&state=STATE
```
The `CLIENT_ID` can be obtained by registering an application in the settings. The `STATE` is a random string that will be sent back to your application after the user authorizes. The `state` parameter is optional, but should be used to prevent CSRF attacks.
![Authorization Page](/authorize.png)
The user will now be asked to authorize your application. If they authorize it, the user will be redirected to the `REDIRECT_URL`, for example:
```curl
https://[REDIRECT_URI]?code=RETURNED_CODE&state=STATE
```
2. Using the provided `code` from the redirect, you can request a new application and refresh token. The access token endpoint accepts POST requests with `application/json` and `application/x-www-form-urlencoded` body, for example:
```curl
POST https://[YOUR-GITEA-URL]/login/oauth/access_token
```
```json
{
"client_id": "YOUR_CLIENT_ID",
"code": "RETURNED_CODE",
"grant_type": "authorization_code",
"redirect_uri": "REDIRECT_URI",
"code_verifier": "CODE_VERIFIER",
}
```
Response:
```json
{
"access_token": "eyJhbGciOiJIUzUxMiIsInR5cCI6IkpXVCJ9.eyJnbnQiOjIsInR0IjowLCJleHAiOjE1NTUxNzk5MTIsImlhdCI6MTU1NTE3NjMxMn0.0-iFsAwBtxuckA0sNZ6QpBQmywVPz129u75vOM7wPJecw5wqGyBkmstfJHAjEOqrAf_V5Z-1QYeCh_Cz4RiKug",
"token_type": "bearer",
"expires_in": 3600,
"refresh_token": "eyJhbGciOiJIUzUxMiIsInR5cCI6IkpXVCJ9.eyJnbnQiOjIsInR0IjoxLCJjbnQiOjEsImV4cCI6MTU1NzgwNDMxMiwiaWF0IjoxNTU1MTc2MzEyfQ.S_HZQBy4q9r5SEzNGNIoFClT43HPNDbUdHH-GYNYYdkRfft6XptJBkUQscZsGxOW975Yk6RbgtGvq1nkEcklOw"
}
```
The `REDIRECT_URI` in the `access_token` request must match the `REDIRECT_URI` in the `authorize` request.
3. Use the `access_token` to make [API requests](https://docs.gitea.io/en-us/api-usage#oauth2) to access the user's resources.