This app implements the OAuth 2.0 Authorization Code Flow.

Place the content of this repository in owncloud/apps/oauth2.

• Authorization URL: /index.php/apps/oauth2/authorize
• Access Token URL: /index.php/apps/oauth2/api/v1/token

1. Client registration: First the clients have to be registered in the admin settings: /index.php/settings/admin?sectionid=additional#oauth2. You need to specify a name for the client (the name is unrelated to the OAuth 2.0 protocol and is just used to recognize it later) and the redirection URI. A client identifier and client secret is being generated when adding a new client. They both consist of 64 characters.

2. Authorization Request: For every registered client an Authorization Request can be made. The client redirects the resource owner to the Authorization URL and requests authorization. The following URL parameters have to be specified:

   1. response_type (required): needs to be code because at this time only the Authorization Code Flow is implemented.
   2. client_id (required): the client identifier obtained when registering the client.
   3. redirect_uri (required): the redirection URI specified when registering the client.
   4. state (optional): can be set by the client "to maintain state between the request and callback" (RFC 6749).
   5. user (optional): can be set to indicate the username of the resource owner

3. Authorization Response: After the resource owner's authorization the app redirects to the redirect_uri specified in the Authorization Request and adds the Authorization Code as URL parameter code. An Authorization Code is valid for 10 minutes.

4. Access Token Request: With the Authorization Code the client can request an Access Token using the Access Token URL. Client Authentication is done using Basic Auth with the client identifier as username and the client secret as password. The following URL parameters have to be specified:

   1. grant_type : Either authorization_code or refresh_token.
   2. code and redirect_uri (if the grant type authorization_code is used).
   3. refresh_token (if the grant type refresh_token is used).

5. Access Token Response: The app responses to a valid Access Token Request with an JSON response like the following. An Access Token is valid for 1 hour and can be refreshed with a Refresh Token.

{
    "access_token" : "1vtnuo1NkIsbndAjVnhl7y0wJha59JyaAiFIVQDvcBY2uvKmj5EPBEhss0pauzdQ",
    "token_type" : "Bearer",
    "expires_in" : 3600,
    "refresh_token" : "7y0wJuvKmj5E1vjVnhlPBEhha59JyaAiFIVQDvcBY2ss0pauzdQtnuo1NkIsbndA",
    "user_id" : "admin",
    "message_url" : "https://www.example.org/owncloud/index.php/apps/oauth2/authorization-successful"
}

Since no user passwords are handled by the app at all only master key encryption is working (similiar to the Shibboleth app).

• [ ] Add option for using different scopes.