--- date: "2023-06-01T08:40:00+08:00" title: "OAuth2 provider" slug: "oauth2-provider" weight: 41 toc: false draft: false aliases: - /en-us/oauth2-provider menu: sidebar: parent: "development" name: "OAuth2 Provider" weight: 41 identifier: "oauth2-provider" --- # OAuth2 provider **Table of Contents** {{< toc >}} 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 Gitea supports the following scopes for tokens: | Name | Description | | ---- | ----------- | | **(no scope)** | Grants read-only access to public user profile and public repositories. | | **repo** | Full control over all repositories. | |     **repo:status** | Grants read/write access to commit status in all repositories. | |     **public_repo** | Grants read/write access to public repositories only. | | **admin:repo_hook** | Grants access to repository hooks of all repositories. This is included in the `repo` scope. | |     **write:repo_hook** | Grants read/write access to repository hooks | |     **read:repo_hook** | Grants read-only access to repository hooks | | **admin:org** | Grants full access to organization settings | |     **write:org** | Grants read/write access to organization settings | |     **read:org** | Grants read-only access to organization settings | | **admin:public_key** | Grants full access for managing public keys | |     **write:public_key** | Grant read/write access to public keys | |     **read:public_key** | Grant read-only access to public keys | | **admin:org_hook** | Grants full access to organizational-level hooks | | **admin:user_hook** | Grants full access to user-level hooks | | **notification** | Grants full access to notifications | | **user** | Grants full access to user profile info | |     **read:user** | Grants read access to user's profile | |     **user:email** | Grants read access to user's email addresses | |     **user:follow** | Grants access to follow/un-follow a user | | **delete_repo** | Grants access to delete repositories as an admin | | **package** | Grants full access to hosted packages | |     **write:package** | Grants read/write access to packages | |     **read:package** | Grants read access to packages | |     **delete:package** | Grants delete access to packages | | **admin:gpg_key** | Grants full access for managing GPG keys | |     **write:gpg_key** | Grants read/write access to GPG keys | |     **read:gpg_key** | Grants read-only access to GPG keys | | **admin:application** | Grants full access to manage applications | |     **write:application** | Grants read/write access for managing applications | |     **read:application** | Grants read access for managing applications | | **sudo** | Allows to perform actions as the site admin. | ## 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.